hnbgw_rx_hnb_register_req(): guard against asn.1 parsing errors

I considered putting these checks into
hnbap_decode_hnbregisterrequesties() itself, but that code is generated
by asn1tostruct.py, so it is non-trivial.

So I decided to add this code bit, to guard against potential NULL deref
induced by input from the wire, which coverity complains about.

Related: CID#465551
Change-Id: I555f11cadc23ea231821bd48f7cd62953b022e9e

.gitignore

@@ -2,6 +2,7 @@ hnbgwdebian/*.log
 *.o
 *.lo
 *.a
+*.la
 .deps
 Makefile
 Makefile.in
@@ -67,6 +68,7 @@ doc/manuals/*__*.png
 doc/manuals/*.check
 doc/manuals/generated/
 doc/manuals/osmohnbgw-usermanual.xml
+doc/manuals/vty/hnbgw_vty_reference.xml
 doc/manuals/common
 doc/manuals/build
 

Makefile.am

@@ -19,7 +19,6 @@ SUBDIRS = \
 BUILT_SOURCES = $(top_srcdir)/.version
 EXTRA_DIST = \
 	     .version \
-	     contrib/osmo-hnbgw.spec.in \
 	     debian \
 	     git-version-gen \
 	     osmoappdesc.py \

README.md

@@ -19,9 +19,9 @@ GIT Repository
 
 You can clone from the official osmo-hnbgw.git repository using
 
-	git clone git://git.osmocom.org/osmo-hnbgw.git
+	git clone https://gitea.osmocom.org/cellular-infrastructure/osmo-hnbgw
 
-There is a cgit interface at https://git.osmocom.org/osmo-hnbgw/
+There is a web interface at https://gitea.osmocom.org/cellular-infrastructure/osmo-hnbgw
 
 Documentation
 -------------

TODO-RELEASE

@@ -1,9 +1,10 @@
 # When cleaning up this file: bump API version in corresponding Makefile.am and rename corresponding debian/lib*.install
-# according to https://www.gnu.org/software/libtool/manual/html_node/Updating-version-info.html#Updating-version-info
-# In short:
+# according to https://osmocom.org/projects/cellular-infrastructure/wiki/Make_a_new_release
+# In short: https://www.gnu.org/software/libtool/manual/html_node/Updating-version-info.html#Updating-version-info
 # LIBVERSION=c:r:a
 # If the library source code has changed at all since the last update, then increment revision: c:r + 1:a.
-# If any interfaces have been added, removed, or changed since the last update: c + 1:0:0.
+# If any interfaces have been added, removed, or changed since the last update: c + 1:0:a.
 # If any interfaces have been added since the last public release: c:r:a + 1.
 # If any interfaces have been removed or changed since the last public release: c:r:0.
-#library	what		description / commit summary line
+#library	what			description / commit summary line
+libosmo-sigtran >2.1.0    osmo_sccp_addr_{create,update}()

configure.ac

@@ -37,8 +37,6 @@ fi
 PKG_PROG_PKG_CONFIG([0.20])
 
 dnl checks for libraries
-AC_SEARCH_LIBS([dlopen], [dl dld], [LIBRARY_DL="$LIBS";LIBS=""])
-AC_SUBST(LIBRARY_DL)
 old_LIBS=$LIBS
 AC_SEARCH_LIBS([sctp_recvmsg], [sctp], [
 	AC_DEFINE(HAVE_LIBSCTP, 1, [Define 1 to enable SCTP support])
@@ -51,16 +49,36 @@ AC_SEARCH_LIBS([sctp_recvmsg], [sctp], [
 LIBS=$old_LIBS
 
 PKG_CHECK_MODULES(LIBASN1C, libasn1c >= 0.9.30)
-PKG_CHECK_MODULES(LIBOSMOCORE, libosmocore >= 1.6.0)
-PKG_CHECK_MODULES(LIBOSMOVTY, libosmovty >= 1.6.0)
-PKG_CHECK_MODULES(LIBOSMOCTRL, libosmoctrl >= 1.6.0)
-PKG_CHECK_MODULES(LIBOSMOGSM, libosmogsm >= 1.6.0)
-PKG_CHECK_MODULES(LIBOSMONETIF, libosmo-netif >= 1.1.0)
-PKG_CHECK_MODULES(LIBOSMOSIGTRAN, libosmo-sigtran >= 1.5.0)
-PKG_CHECK_MODULES(LIBOSMORUA, libosmo-rua >= 1.1.0)
-PKG_CHECK_MODULES(LIBOSMORANAP, libosmo-ranap >= 1.1.0)
-PKG_CHECK_MODULES(LIBOSMOHNBAP, libosmo-hnbap >= 1.1.0)
+PKG_CHECK_MODULES(LIBOSMOCORE, libosmocore >= 1.11.0)
+PKG_CHECK_MODULES(LIBOSMOVTY, libosmovty >= 1.11.0)
+PKG_CHECK_MODULES(LIBOSMOCTRL, libosmoctrl >= 1.11.0)
+PKG_CHECK_MODULES(LIBOSMOGSM, libosmogsm >= 1.11.0)
+PKG_CHECK_MODULES(LIBOSMONETIF, libosmo-netif >= 1.6.0)
+PKG_CHECK_MODULES(LIBOSMOSIGTRAN, libosmo-sigtran >= 2.1.0)
+PKG_CHECK_MODULES(LIBOSMORUA, libosmo-rua >= 1.7.0)
+PKG_CHECK_MODULES(LIBOSMORANAP, libosmo-ranap >= 1.7.0)
+PKG_CHECK_MODULES(LIBOSMOHNBAP, libosmo-hnbap >= 1.7.0)
+PKG_CHECK_MODULES(LIBOSMOMGCPCLIENT, libosmo-mgcp-client >= 1.14.0)
 
+# Enable PFCP support for GTP tunnel mapping via UPF
+AC_ARG_ENABLE([pfcp], [AS_HELP_STRING([--enable-pfcp], [Build with PFCP support, for GTP tunnel mapping via UPF])],
+    [osmo_ac_pfcp="$enableval"],[osmo_ac_pfcp="no"])
+if test "x$osmo_ac_pfcp" = "xyes" ; then
+	PKG_CHECK_MODULES(LIBOSMOPFCP, libosmo-pfcp >= 0.5.0)
+	AC_DEFINE(ENABLE_PFCP, 1, [Define to build with PFCP support])
+fi
+AM_CONDITIONAL(ENABLE_PFCP, test "x$osmo_ac_pfcp" = "xyes")
+AC_SUBST(osmo_ac_pfcp)
+
+# Enable libnftables support for traffic counters using nft
+AC_ARG_ENABLE([nftables], [AS_HELP_STRING([--enable-nftables], [Build with libnftables support, for traffic counters using nft])],
+    [osmo_ac_nftables="$enableval"],[osmo_ac_nftables="no"])
+if test "x$osmo_ac_nftables" = "xyes" ; then
+	PKG_CHECK_MODULES(LIBNFTABLES, libnftables >= 1.0.2)
+	AC_DEFINE(ENABLE_NFTABLES, 1, [Define to build with libnftables support])
+fi
+AM_CONDITIONAL(ENABLE_NFTABLES, test "x$osmo_ac_nftables" = "xyes")
+AC_SUBST(osmo_ac_nftables)
 
 dnl checks for header files
 AC_HEADER_STDC
@@ -142,7 +160,7 @@ if test "x$enable_ext_tests" = "xyes" ; then
 	fi
 	AC_CHECK_PROG(OSMOTESTEXT_CHECK,osmotestvty.py,yes)
 	 if test "x$OSMOTESTEXT_CHECK" != "xyes" ; then
-		AC_MSG_ERROR([Please install git://osmocom.org/python/osmo-python-tests to run the VTY/CTRL tests.])
+		AC_MSG_ERROR([Please install https://gitea.osmocom.org/cellular-infrastructure/osmo-python-tests to run the VTY/CTRL tests.])
 	fi
 fi
 AC_MSG_CHECKING([whether to enable VTY/CTRL tests])
@@ -221,10 +239,12 @@ AC_OUTPUT(
     src/osmo-hnbgw/Makefile
     tests/Makefile
     tests/atlocal
+    tests/ranap_rab_ass/Makefile
+    tests/umts_cell_id/Makefile
     doc/Makefile
     doc/examples/Makefile
     doc/manuals/Makefile
+    doc/charts/Makefile
     contrib/Makefile
     contrib/systemd/Makefile
-    contrib/osmo-hnbgw.spec
     Makefile)

contrib/jenkins.sh

@@ -2,9 +2,13 @@
 # jenkins build helper script for osmo-hnbgw.  This is how we build on jenkins.osmocom.org
 #
 # environment variables:
+# * PFCP: configure PFCP support if set to "1" (default)
 # * WITH_MANUALS: build manual PDFs if set to "1"
+# * NFTABLES: configure nftables support if set to "1" (default)
 # * PUBLISH: upload manuals after building if set to "1" (ignored without WITH_MANUALS = "1")
 #
+PFCP=${PFCP:-1}
+NFTABLES=${NFTABLES:-1}
 
 if ! [ -x "$(command -v osmo-build-dep.sh)" ]; then
 	echo "Error: We need to have scripts/osmo-deps.sh from http://git.osmocom.org/osmo-ci/ in PATH !"
@@ -30,16 +34,24 @@ export LD_LIBRARY_PATH="$inst/lib"
 export PATH="$inst/bin:$PATH"
 
 osmo-build-dep.sh libosmocore "" --disable-doxygen
+osmo-build-dep.sh libosmo-netif "" --disable-doxygen
 osmo-build-dep.sh libosmo-abis
-osmo-build-dep.sh libosmo-netif
-osmo-build-dep.sh libosmo-sccp
+osmo-build-dep.sh libosmo-sigtran "" --disable-doxygen
 osmo-build-dep.sh libasn1c
 osmo-build-dep.sh osmo-iuh
+osmo-build-dep.sh osmo-mgw
 
 # Additional configure options and depends
 CONFIG=""
+if [ "$PFCP" = "1" ]; then
+	osmo-build-dep.sh libosmo-pfcp
+	CONFIG="$CONFIG --enable-pfcp"
+fi
+if [ "$NFTABLES" = "1" ]; then
+	CONFIG="$CONFIG --enable-nftables"
+fi
 if [ "$WITH_MANUALS" = "1" ]; then
-	CONFIG="--enable-manuals"
+	CONFIG="$CONFIG --enable-manuals"
 fi
 
 set +x
@@ -52,7 +64,7 @@ set -x
 
 cd "$base"
 autoreconf --install --force
-./configure --enable-sanitize --enable-external-tests $CONFIG
+./configure --enable-sanitize --enable-external-tests --enable-werror $CONFIG
 $MAKE $PARALLEL_MAKE
 LD_LIBRARY_PATH="$inst/lib" $MAKE check \
   || cat-testlogs.sh

contrib/osmo-hnbgw.spec.in

@@ -1,96 +0,0 @@
-#
-# spec file for package osmo-hnbgw
-#
-# Copyright (c) 2017, Martin Hauke <mardnh@gmx.de>
-#
-# All modifications and additions to the file contributed by third parties
-# remain the property of their copyright owners, unless otherwise agreed
-# upon. The license for this file, and modifications and additions to the
-# file, is the same license as for the pristine package itself (unless the
-# license for the pristine package is not an Open Source License, in which
-# case the license is the MIT License). An "Open Source License" is a
-# license that conforms to the Open Source Definition (Version 1.9)
-# published by the Open Source Initiative.
-
-## Disable LTO for now since it breaks compilation of the tests
-## https://osmocom.org/issues/4113
-%define _lto_cflags %{nil}
-
-Name:           osmo-hnbgw
-Version:        @VERSION@
-Release:        0
-Summary:        OsmoHNBGW: Osmocom's Base Station Controller for 2G CS mobile networks
-License:        AGPL-3.0-or-later AND GPL-2.0-or-later
-Group:          Hardware/Mobile
-URL:            https://osmocom.org/projects/osmohnbgw
-Source:         %{name}-%{version}.tar.xz
-BuildRequires:  automake >= 1.9
-BuildRequires:  libtool >= 2
-BuildRequires:  lksctp-tools-devel
-BuildRequires:  pkgconfig >= 0.20
-%if 0%{?suse_version}
-BuildRequires:  systemd-rpm-macros
-%endif
-BuildRequires:  pkgconfig(libcrypto) >= 0.9.5
-BuildRequires:  pkgconfig(libosmo-netif) >= 1.1.0
-BuildRequires:  pkgconfig(libosmo-sigtran) >= 1.5.0
-BuildRequires:  pkgconfig(libosmoabis) >= 1.2.0
-BuildRequires:  pkgconfig(libosmotrau) >= 1.2.0
-BuildRequires:  pkgconfig(libosmocore) >= 1.6.0
-BuildRequires:  pkgconfig(libosmoctrl) >= 1.6.0
-BuildRequires:  pkgconfig(libosmogb) >= 1.6.0
-BuildRequires:  pkgconfig(libosmogsm) >= 1.6.0
-BuildRequires:  pkgconfig(libosmovty) >= 1.6.0
-BuildRequires:  pkgconfig(libosmo-hnbap) >= 1.1.0
-BuildRequires:  pkgconfig(libosmo-ranap) >= 1.1.0
-BuildRequires:  pkgconfig(libosmo-rua) >= 1.1.0
-BuildRequires:  pkgconfig(talloc)
-BuildRequires:  pkgconfig(libasn1c) >= 0.9.30
-%{?systemd_requires}
-
-%description
-OsmoHNBGW: Osmocom's Home NodeB for 3G mobile networks.
-
-%prep
-%setup -q
-
-%build
-echo "%{version}" >.tarball-version
-autoreconf -fi
-%configure \
-  --docdir=%{_docdir}/%{name} \
-  --with-systemdsystemunitdir=%{_unitdir}
-make %{?_smp_mflags}
-
-%install
-%make_install
-
-%if 0%{?suse_version}
-%preun
-%service_del_preun %{name}.service
-
-%postun
-%service_del_postun %{name}.service
-
-%pre
-%service_add_pre %{name}.service
-
-%post
-%service_add_post %{name}.service
-%endif
-
-%check
-make %{?_smp_mflags} check || (find . -name testsuite.log -exec cat {} +)
-
-%files
-%license COPYING
-%doc AUTHORS README.md
-%{_bindir}/osmo-hnbgw
-%dir %{_docdir}/%{name}/examples
-%dir %{_docdir}/%{name}/examples/osmo-hnbgw
-%{_docdir}/%{name}/examples/osmo-hnbgw/osmo-hnbgw.cfg
-%dir %{_sysconfdir}/osmocom
-%config(noreplace) %{_sysconfdir}/osmocom/osmo-hnbgw.cfg
-%{_unitdir}/%{name}.service
-
-%changelog

contrib/systemd/osmo-hnbgw.service

@@ -1,9 +1,16 @@
 [Unit]
 Description=Osmocom Home Nodeb Gateway (OsmoHNBGW)
+After=network-online.target
+Wants=network-online.target
 
 [Service]
 Type=simple
 Restart=always
+LimitNOFILE=65536
+StateDirectory=osmocom
+WorkingDirectory=%S/osmocom
+User=osmocom
+Group=osmocom
 ExecStart=/usr/bin/osmo-hnbgw -c /etc/osmocom/osmo-hnbgw.cfg
 RestartSec=2
 

debian/changelog

@@ -1,3 +1,378 @@
+osmo-hnbgw (1.7.0) unstable; urgency=medium
+
+  [ Neels Janosch Hofmeyr ]
+  * drop config.vty tests from make check
+  * coverity CID#358071
+  * coverity CID#358072
+  * coverity CID#358070
+  * coverity CID#358069
+  * on RUA Connect failure, respond with RUA Disconnect
+  * on RUA DT for unknown context, respond with RUA Disconnect
+
+  [ Harald Welte ]
+  * hnb_persistent: Use incrementing counter for rate_ctr + stat_item index
+  * Revert "hnb_persistent: Use incrementing counter for rate_ctr + stat_item index"
+
+  [ Oliver Smith ]
+  * contrib/jenkins: libosmo-sccp -> libosmo-sigtran
+
+  [ Pau Espin Pedrol ]
+  * Log cn_disconnect.ind cause
+  * Fix SCCP RLSD not sent upon rx RUA Disconnect due to error condition
+  * ps_rab_ass_fsm: Fix uninitialized ptr access
+  * Add PFCP stats item group
+  * hnbgw: Avoid using struct osmo_pfcp_cp_peer fields directly
+  * hnbgw: Fix wrong map object retrieved from hashtable
+  * Use new libosmo-sigtran APIs to access osmo_ss7_instance
+  * jenkins.sh: libosmo-netif no longer depends on libosmo-abis
+  * jenkins.sh: No need to build libosmo-sigtran with doxygen
+  * map_sccp: Fix crash during ev MAP_SCCP_EV_RAN_DISC in st MAP_SCCP_ST_WAIT_CC
+  * peek_l3_ul_nas: Split parsing logic based on PS/CS ctx
+  * peek_l3_ul_nas: Improve RAU req parsing checks
+  * peek_l3_ul_nas: Improve GMM Attach Req parsing checks
+  * peek_l3_ul_nas: Parse PTMSI MI from GMM RAU req
+
+ -- Oliver Smith <osmith@sysmocom.de>  Wed, 12 Feb 2025 14:37:35 +0100
+
+osmo-hnbgw (1.6.0) unstable; urgency=medium
+
+  [ Pau Espin Pedrol ]
+  * hnbgw_cn: Remove assert hit due to wrong assumption
+  * Increase default X31 val from 5 to 15 seconds
+  * context_map_sccp: Fix assert hit due to missing ev handling
+  * tests/ranap_rab_ass: Test RAB-Ass.req with X.213 IPv4 address len=7
+  * mgw_fsm: Assume IuUP HNB IP addr = Iuh during MGCP CRCX on RAN side
+  * mgw_fsm: Modify RAB on HNB if IuUP local IP addr at MGW changes during MDCX
+  * hnbap: Avoid calling duplicate getpeername() for each registered HNB
+
+  [ Neels Janosch Hofmeyr ]
+  * X31: fix vty doc
+  * allow (second) CS RAB Assignment Request without RTP info
+  * systemd,manual: set LimitNOFILE=65536
+  * rua: validate correct RUA ctx state per RUA message type
+  * rua: move from ERROR to DEBUG log: stray RUA Disconnect
+  * pfcp: fix modification of wrong FAR ID
+  * tweak vty doc: "UDP port"
+  * add tests/pfcp_cfg.vty.with_pfcp
+  * pfcp: fix missing vty_write of pfcp local-port
+  * pfcp: implement sending Network Instance IEs
+  * fix null deref on hnb_context_release
+  * drop legacy hack: do not start MGW endp in loopback mode
+  * fixup: compilation error: unused var in map_rua_init_action()
+  * fix rate_ctr leak in hnb_persistent_free()
+  * per-HNB GTP-U traffic counters via nft
+  * add hnb_persistent hashtable: optimize lookup by cell id
+  * fix stat_item leak in hnb_persistent_free()
+  * use osmo_jhash for the hnb_persistent hashtable
+  * rename to umts_cell_id_to_str()
+  * umts_cell_id: add umts_cell_id_to_str_buf()
+  * add umts_cell_id_test.c
+  * 3-digit MNC: use osmo_plmn_id in struct umts_cell_id
+  * add LOG_HNBP() for hnb_persistent
+  * hnb_persistent: introduce disconnected timeout
+  * prevent use-after-free after FSM instance termination
+  * improve HNBAP error logging
+  * nft-kpi: log errors of counter retrieval
+  * nft-kpi: remove X34 drifting: adjust delay by elapsed time
+  * drop list of HNBAP UE Context
+  * dbg log: nft kpi: clarify nr of rate ctrs vs nr of hnbp
+  * fix MGCP compat with osmo-mgw <= 1.12.2: CRCX in recvonly
+
+  [ Andreas Eversberg ]
+  * Use uniform log format for default config files
+
+  [ Harald Welte ]
+  * Display RANAP state during 'show cnlink'
+  * Fix license headers: Should have been AGPLv3+, not GPLv2+
+  * [cosmetic] re-order hnbgw.c to group code in major blocks
+  * umts_cell_id_name: Use 3-digit MCC and 2/3-digit MNC based on VTY config
+  * osmo_hnbgw_main: Install our usual SIGUSR1/SIGUSR2/SIGABRT handlers
+  * Introduce umts_cell_id_from_str() as inverse of umts_cell_id_name()
+  * Introduce concept of per-HNB persistent data structure
+  * Set persistent->ctx pointer on HNB REGISTER REQ
+  * New per-hnb rate_ctr and stat_item groups; track uptime
+  * Various new per-hnb RANAP and RUA counters
+  * stats: Introduce CNLINK counter macros
+  * stats: Introduce CNPOOL counter macro
+  * stats: Introduce basic counters for RANAP unit-data from CN links
+  * cosmetic: Fix comment in mgw_fsm.c: One RAB per context_map, not hnb!
+  * cosmetic: talk about cs_rab_ass_* when working in CS domain
+  * cosmetic: Rename hnbgw_rx_ranap and friends to *_rx_ranap_udt_ul
+  * rename hnbgw_peek_l3 to hnbgw_peek_l3_ul as it's uplink only
+  * don't forward paging requests to HNB's not yet registered
+  * vty: Print the uptime during 'show hnb' output
+  * Introduce counter for per-hnb cumulative active CS RAB duration
+  * stats: Add per-hnb paging:{cs,ps}:attempted counter
+  * cosmetic: align downlink RANAP unitdata function names with uplink
+  * mgw_fsm: Add some OSMO_ASSERT() to ensure only CS maps passed
+  * RAB activation/modification/release statistics
+  * context_map_{rua,sccp}: Re-order to always process KPIs
+  * generalize hnbgw_tx_ue_register_rej_tmsi() to hnbgw_tx_ue_register_rej()
+  * HNBAP: Use proper cause values during HNB-REGISTER-REQ processing
+  * HNBAP: Send HNB-REGISTER-REJ on ASN.1 decoding error
+  * HNBAP: Always respond to UE-REGISTER-REQUEST
+  * HNBAP: Make sure to respond with correct "reject"
+  * HNBAP: Transmit ErrorIndication in more situations
+  * HNBAP: use GSM23003_IMSI_MAX_DIGITS instead of magic number
+  * HNBAP: Support IMSI identity type in hnbgw_tx_ue_register_rej()
+  * counters: Distinguish between normal and abnormal release cause
+  * KPI: Add initial set of DTAP message type rate counters
+  * kpi_ranap: Avoid null pointer de-ref during HNB shutdown
+
+  [ Oliver Smith ]
+  * gitignore: add *.la, hnbgw_vty_reference.xml
+  * debian: fix having no manuals in osmo-hnbgw-doc
+  * .deb/.rpm: various fixes related to non-root
+  * contrib: remove rpm spec file
+  * debian/postinst: add checks, be verbose
+  * contrib/jenkins: set --enable-werror
+
+  [ Max ]
+  * .deb/.rpm: add osmocom user during package install
+
+ -- Oliver Smith <osmith@sysmocom.de>  Thu, 25 Jul 2024 10:05:58 +0200
+
+osmo-hnbgw (1.5.0) unstable; urgency=medium
+
+  [ Neels Janosch Hofmeyr ]
+  * UE state leak: when HNB re-registers, discard previous UE state
+  * Deprecate 'sccp cr max-payload-len', remove SCCP CR limit code
+  * cosmetic: drop stray backslash
+  * drop obsolete fixme comment
+  * various comment tweaks
+  * log tweak
+  * cosmetic: rename context_map_deactivate
+  * fix deprecation: use ranap_cn_rx_co_decode2()
+  * rua_to_scu(): drop dead code for connection-less
+  * use RUA procedure code for rua_to_scu() arg
+  * cosmetic: regroup members of hnbgw_context_map
+  * add design charts for new context map FSMs
+  * context map: introduce RUA and SCCP FSMs to fix leaks
+  * log osmo_fsm timeouts
+  * sccp_sap_up(): ignore PCSTATE.ind
+  * fix regression: unbreak PFCP: PS RAB via UPF proxying
+  * tweak LOGHNB()
+  * debug log: log received RANAP message types on DCN, DHNB
+  * map_sccp: on timeout during WAIT_CC, send N-DISCONNECT to SCCP-SCOC
+  * release UE Contexts on HNB (Re-)Register
+  * release UE Contexts on SCTP_RESTART
+  * log: in new RUA,SCCP FSM IDs, indicate CS/PS
+  * vty: 'show ue': show which HNB the UE is registered on
+  * fix vty: show talloc-context all
+  * place asn1 context under hnb_ctx for better visibility
+  * fix asn1 leak in handle_cn_ranap()
+  * fix asn1 leak in error path of hnbgw_tx_ue_register_acc()
+  * fix asn1 leak in error path of hnbgw_tx_ue_register_acc_tmsi()
+  * fix asn1 leaks in ps_rab_ass_resp_send_if_ready()
+  * fix asn1 leak in hnbgw_rua_rx()
+  * less code dup in mem free of hnbgw_rx_ue_register_req()
+  * fix log msg typo 'Unsupportedccept'
+  * actually run vty-tests: VTY transcript tests
+  * actually run vty-tests: osmotestvty.py
+  * rab_ass_fsm.c: fix asn1 memleak when replacing GTP address
+  * ps_rab_ass_fsm.h: fix dup of FSM event enum
+  * drop empty hnbgw_rua_init()
+  * eliminate function hnb_contexts()
+  * vty: fix doc strings for 'show {hnb,ue}'
+  * actually run vty-tests: osmotestconfig.py
+  * drop ctrl_test_runner.py
+  * comment typo fix in ranap_rab_ass.c
+  * simplify: one g_hnbgw as global state and root ctx
+  * ranap_rab_ass_test.c: clarify talloc contexts
+  * move main() to separate file
+  * add non-installed libhnbgw.la for test linkage
+  * vty: make legacy 'hnbgw'/'sccp cr max...' fatal
+  * vty test: show missing write-back of 'rnc-id'
+  * fix missing write-back of rnc-id
+  * drop dead code: cnlink.T_RafC
+  * remove obsolete context_map_check_released() call
+  * unbloat: drop context_map_check_released()
+  * vty_go_parent(): remove legacy cruft
+  * immediately SCCP RLSD on HNB re-register
+  * use new osmo_sccp_instance_next_conn_id()
+  * add doc/examples/osmo-hnbgw/osmo-hnbgw-cs7.cfg
+  * add separate cfg file only for VTY tests
+  * add startup config tests
+  * charts: add sccp.dot
+  * cnpool: allow separate cs7 for IuPS and IuCS
+  * coverity: fix type of local var
+  * cnpool: split up context_map_find_or_create_by_rua_ctx_id()
+  * cnpool prep: add SCCP_EV_USER_ABORT
+  * cnpool: add multiple 'msc' and 'sgsn' cfg (use only the first)
+  * cnpool: examples and config tests: use 'msc 0'/'sgsn 0' syntax
+  * cnpool: make NRI mappings VTY configurable
+  * tdefs; combine timer groups 'ps' and 'cmap' to 'hnbgw'
+  * add hnbgw_decode_ranap_co()
+  * fixup for 'cnpool: split up context_map_find_...'
+  * startup config tests: show default 'msc 0', 'sgsn 0'
+  * cnpool: extract Mobile Identity from RANAP payload
+  * add rate_ctr infra; add rate_ctrs for cnpool
+  * add CTRL transcript tests for cnpool rate ctrs
+  * cnpool: select CN link from pool by NRI or round robin
+  * doc/examples/osmo-hnbgw/osmo-hnbgw-cnpool.cfg
+  * fix umts_cell_id_name(): show CID
+  * make public: umts_cell_id_name()
+  * tweak lots of logging
+  * ctrl test: also test msc 1
+  * cnpool: add context_map_cnlink_lost() handling
+  * add ranap_domain_name()
+  * detect in/active CN links by RANAP RESET
+  * use cnlink state in cnpool decisions
+  * cnpool: return Paging Resp to the exact CN link that Paged
+  * cfg: add 'hnbgw' / 'plmn MCC MNC'
+  * include Global RNC-ID in RESET
+  * include Global RNC-ID in RESET-ACK
+  * RUA: log tweak
+  * coverity: hnbgw_cn: avoid NULL deref in LOGP
+
+  [ Philipp Maier ]
+  * mgw_fsm: fix typo
+  * mgw_fsm: fix log line
+  * mgw_fsm: use __func__ to mention function name in log line
+  * mgw_fsm: refactor helper function handle_rab_release()
+  * ranap_rab_ass: do not free never allocated FieldItems
+  * ranap_rab_ass: be sure to initialize memory with 0
+
+  [ Vadim Yanitskiy ]
+  * tests: use check_PROGRAMS for tests, not noinst_PROGRAMS
+  * tests: use -no-install libtool flag to avoid ./lt-* scripts
+  * tests: make 'vty-test' target depend on osmo-hnbgw binary
+  * tests: do not depend on undefined $(BUILT_SOURCES)
+  * copyright: fix typo: sysmocom s/s.m.f.c./s.f.m.c./ GmbH
+
+  [ Oliver Smith ]
+  * hnbgw_mgw_setup: use mgcp_client_pool_empty()
+  * debian: set compat level to 10
+  * contrib/jenkins.sh: add PFCP variable
+  * hnbgw: put copyright into define
+  * systemd: depend on networking-online.target
+
+  [ Pau Espin Pedrol ]
+  * manuals: include osmo-gsm-manual's sigtran.adoc
+  * tests: Update *.vty after libosmo-sccp VTY improvements
+  * Use new mgcp_client_conf_alloc() API to alloc mgcp_client_conf
+  * Tear down call if local IuUP MGW address changed during MDCX
+
+ -- Pau Espin Pedrol <pespin@sysmocom.de>  Tue, 12 Sep 2023 17:18:43 +0200
+
+osmo-hnbgw (1.4.0) unstable; urgency=medium
+
+  [ Pau Espin Pedrol ]
+  * hnbgw_cn.c: Guard against null ss7 ptr during init
+  * cosmetic: Fix typo in log and whitespace
+  * hnbgw: Log new SCTP HNB connections
+  * hnb_context_release(): Make sure assigned conn is freed
+  * Improve logging around hnb_context and sctp conn lifecycle
+  * Change log level about conn becoming closed to NOTICE
+  * hnbgw: Unregister HNB if SCTP link is restarted
+  * hnbgw: Fix recent regression not closing conn upon rx of SCTP_SHUTDOWN_EVENT
+  * hnbap: Accept duplicated HNB Register Request on same conn
+  * hnbap: Improve logging around HNBAP HNB Register Request
+  * Workaround bug where old hnb_context from same remote addr+port is kept
+  * Fix handling of sctp SCTP_SHUTDOWN_EVENT notification
+  * Close conn when receiving SCTP_ASSOC_CHANGE notification
+  * hnb_read_cb: use local var to reduce get_ofd() calls
+  * hnb_read_cb(): -EBADF must be returned if conn is freed to avoid use-after-free
+  * Clear SCTP tx queue upon SCTP RESTART notification
+  * Makefile.am: Drop duplicated LIBOSMOMGCPCLIENT_LIBS
+  * Introduce support for libosmo-mgcp-client MGW pooling
+  * doc: Include mgwpool.adoc from osmo-gsm-manuals
+  * vty: Fix timers not printed when dumping running-config
+  * hnbgw: Avoid allocating SCCP conn id >0x00fffffe
+  * context_map: Lower loglevel to INFO when deallocating context IDs
+
+  [ Neels Hofmeyr ]
+  * mgw_fsm: move MGCP timeout to mgw_fsm_T_defs
+  * fix test_ranap_rab_ass_resp_decode_encode
+  * ranap_rab_ass_req_encode(): return msgb
+  * add ps_rab_ass FSM to map GTP via UPF
+  * reduce code dup in handle_cn_data_ind()
+  * build: add --enable-pfcp, make PFCP dep optional
+  * optimize: decode PS msgs only when PFCP is enabled
+  * ps_rab_fsm: check use cb success
+  * add example osmo-hnbgw-pfcp.cfg
+  * manual: add missing bit on the MGCP port
+  * manual: update overview chart with PFCP
+  * manual: update IuCS/IuPS protocol stack chart
+  * manual: explain the PFCP port
+  * example cfg: tweak logging
+  * debian,RPM: package with PFCP support
+
+  [ Vadim Yanitskiy ]
+  * tests/ranap_rab_ass: fix potential NULL pointer dereferences
+  * configure.ac: do not require unused dlopen
+
+  [ Oliver Smith ]
+  * rpm spec: add osmo-hnbgw-pfcp.cfg
+
+  [ Daniel Willmann ]
+  * Install show talloc-context VTY commands
+  * hnbgw_hnbap: Fix memory leaks in HNBAP handling
+
+  [ Harald Welte ]
+  * packate the new osmo-hnbgw-pfcp.cfg example config file
+  * cosmetic: Fix typos
+  * Abort if processing SCTP connection without HNB context
+  * hnbgw_rx_hnb_deregister: Don't call hnb_context_release()
+  * Don't process RUA messages if HNB is not registered
+  * Don't permit anything but HNB (de)registration until HNB is registered
+
+  [ Neels Janosch Hofmeyr ]
+  * fix regression: in RUA, do PFCP only when enabled
+  * do not depend on libosmo-gtlv
+  * drop bogus error log 'no MGW fsm'
+  * fix segfault on MGCP timeout
+  * fix msgb leak for RANAP RAB Ass. Req.
+  * fix possible leak of ue_context on UE REGISTER error
+  * fix SCCP conn leak on non-graceful HNB shutdown
+  * coverity: hnbgw_rua.c: remove redundant check
+
+  [ Max ]
+  * Set working directory in systemd service file
+  * ctrl: take both address and port from vty config
+
+  [ arehbein ]
+  * osmo-hnbgw: Transition to use of 'telnet_init_default'
+
+ -- Pau Espin Pedrol <pespin@sysmocom.de>  Tue, 07 Feb 2023 18:05:46 +0100
+
+osmo-hnbgw (1.3.0) unstable; urgency=medium
+
+  [ Philipp Maier ]
+  * hnbgw_cn.c: fix sourcecode formatting
+  * hbgw_hnbap: use osmo_plmn_from_bcd instead of gsm48_mcc_mnc_from_bcd
+  * ranap_rab_ass: add decoder and rewrite functions for RAB-AssignmentRequest/Response
+  * ranap_rab_ass: ensure specific rab_id
+  * ranap_rab_ass: add function to check if RAB is in FailureList
+  * ranap_rab_ass: add function to check if RAB is in ReleaseList
+  * ranap_rab_ass_test: cosmetic: correct test function names
+  * mgw_fsm: add MGW support to osmo-hnbgw
+  * overview.adoc: update network diagram
+  * running.adoc: explain MGW configuration
+  * osmo-hnbgw.cfg: use local port 2729 as default for MGCP client
+  * mgw_fsm: release call when FSM is not created
+  * ranap_rab_ass: check for more than one RAB assignment req
+
+  [ Neels Hofmeyr ]
+  * use osmo_select_main_ctx(), tweak log in handle_cn_conn_conf()
+  * allow calling rua_to_scu() without data
+  * tweak comments in rua_to_scu()
+  * add option to send SCCP CR without payload
+  * fix segfault in error handling for mgw_fi == NULL
+
+  [ Pau Espin Pedrol ]
+  * mgw_fsm: Mark structs as static const
+  * mgw_fsm: Improve logging
+  * cosmetic: mgw_fsm: Fix typo in log
+  * mgw_fsm: Change macro to not use local variables implicitly
+  * mgw_fsm: Fix error path accessing uninitialized fsm ptr
+  * mgw_fsm: Simplify cleanup paths
+
+  [ Harald Welte ]
+  * update URLs (git -> https; gitea)
+
+ -- Pau Espin Pedrol <pespin@sysmocom.de>  Wed, 29 Jun 2022 12:42:35 +0200
+
 osmo-hnbgw (1.2.1) unstable; urgency=medium
 
   * Do not turn some compiler warnings into errors by default

debian/compat

@@ -1 +1 @@
-9
+10

debian/control

@@ -2,7 +2,7 @@ Source: osmo-hnbgw
 Section: net
 Priority: extra
 Maintainer: Osmocom team <openbsc@lists.osmocom.org>
-Build-Depends: debhelper (>=9),
+Build-Depends: debhelper (>= 10),
                dh-autoreconf,
                autotools-dev,
                autoconf,
@@ -13,17 +13,20 @@ Build-Depends: debhelper (>=9),
                libtalloc-dev,
                libasn1c-dev (>= 0.9.30),
                libsctp-dev,
-               libosmocore-dev (>= 1.6.0),
-               libosmo-sigtran-dev (>= 1.5.0),
-               libosmo-abis-dev (>= 1.2.0),
-               libosmo-netif-dev (>= 1.1.0),
-               libosmo-hnbap-dev (>= 1.1.0),
-               libosmo-ranap-dev (>= 1.1.0),
-               libosmo-rua-dev (>= 1.1.0),
-               osmo-gsm-manuals-dev (>= 1.2.0)
+               libosmocore-dev (>= 1.11.0),
+               libosmo-sigtran-dev (>= 2.1.0),
+               libosmo-abis-dev (>= 2.0.0),
+               libosmo-netif-dev (>= 1.6.0),
+               libosmo-mgcp-client-dev (>= 1.14.0),
+               libosmo-hnbap-dev (>= 1.7.0),
+               libosmo-ranap-dev (>= 1.7.0),
+               libosmo-rua-dev (>= 1.7.0),
+               libosmo-pfcp-dev (>= 0.5.0),
+               libnftables-dev,
+               osmo-gsm-manuals-dev (>= 1.6.0)
 Standards-Version: 3.9.8
-Vcs-Git: git://git.osmocom.org/osmo-hnbgw.git
-Vcs-Browser: https://git.osmocom.org/osmo-hnbgw/
+Vcs-Git: https://gitea.osmocom.org/cellular-infrastructure/osmo-hnbgw
+Vcs-Browser: https://gitea.osmocom.org/cellular-infrastructure/osmo-hnbgw
 Homepage: https://projects.osmocom.org/projects/osmo-hnbgw
 
 Package: osmo-hnbgw

debian/copyright

@@ -1,6 +1,6 @@
 Format: http://www.debian.org/doc/packaging-manuals/copyright-format/1.0/
 Upstream-Name: osmo-hnbgw
-Source: git://git.osmocom.org/osmo-hnbgw
+Source: https://gitea.osmocom.org/cellular-infrastructure/osmo-hnbgw
 
 Files:     *
 Copyright: 2021 sysmocom - s.f.m.c. GmbH <info@sysmocom.de>

debian/osmo-hnbgw-doc.install

@@ -0,0 +1,2 @@
+usr/share/doc/osmo-hnbgw-doc/*.pdf
+

debian/osmo-hnbgw.install

@@ -2,3 +2,6 @@ etc/osmocom/osmo-hnbgw.cfg
 lib/systemd/system/osmo-hnbgw.service
 usr/bin/osmo-hnbgw
 usr/share/doc/osmo-hnbgw/examples/osmo-hnbgw/osmo-hnbgw.cfg usr/share/doc/osmo-hnbgw/examples
+usr/share/doc/osmo-hnbgw/examples/osmo-hnbgw/osmo-hnbgw-pfcp.cfg usr/share/doc/osmo-hnbgw/examples
+usr/share/doc/osmo-hnbgw/examples/osmo-hnbgw/osmo-hnbgw-cs7.cfg usr/share/doc/osmo-hnbgw/examples
+usr/share/doc/osmo-hnbgw/examples/osmo-hnbgw/osmo-hnbgw-cnpool.cfg usr/share/doc/osmo-hnbgw/examples

debian/postinst

@@ -0,0 +1,38 @@
+#!/bin/sh -e
+case "$1" in
+	configure)
+		# Create the osmocom group and user (if it doesn't exist yet)
+		if ! getent group osmocom >/dev/null; then
+			groupadd --system osmocom
+		fi
+		if ! getent passwd osmocom >/dev/null; then
+			useradd \
+				--system \
+				--gid osmocom \
+				--home-dir /var/lib/osmocom \
+				--shell /sbin/nologin \
+				--comment "Open Source Mobile Communications" \
+				osmocom
+		fi
+
+		# Fix permissions of previous (root-owned) install (OS#4107)
+		if dpkg --compare-versions "$2" le "1.6.0"; then
+			if [ -e /etc/osmocom/osmo-hnbgw.cfg ]; then
+				chown -v osmocom:osmocom /etc/osmocom/osmo-hnbgw.cfg
+				chmod -v 0660 /etc/osmocom/osmo-hnbgw.cfg
+			fi
+
+			if [ -d /etc/osmocom ]; then
+				chown -v root:osmocom /etc/osmocom
+				chmod -v 2775 /etc/osmocom
+			fi
+
+			mkdir -p /var/lib/osmocom
+			chown -R -v osmocom:osmocom /var/lib/osmocom
+		fi
+		;;
+esac
+
+# dh_installdeb(1) will replace this with shell code automatically
+# generated by other debhelper scripts.
+#DEBHELPER#

debian/rules

@@ -44,10 +44,18 @@
 %:
 	dh $@ --with autoreconf
 
-# debmake generated override targets
-CONFIGURE_FLAGS += --with-systemdsystemunitdir=/lib/systemd/system --enable-manuals
+# libnftables is too old in Debian 10 (OS#6425)
 override_dh_auto_configure:
-	dh_auto_configure -- $(CONFIGURE_FLAGS)
+	CONFIGURE_FLAGS=" \
+		--enable-manuals \
+		--enable-pfcp \
+		--with-systemdsystemunitdir=/lib/systemd/system \
+	"; \
+	if pkg-config --exists libnftables --atleast-version=1.0.2; then \
+		CONFIGURE_FLAGS="$$CONFIGURE_FLAGS --enable-nftables"; \
+	fi; \
+	dh_auto_configure -- $$CONFIGURE_FLAGS
+
 #
 # Do not install libtool archive, python .pyc .pyo
 #override_dh_install:

doc/Makefile.am

@@ -1,4 +1,5 @@
 SUBDIRS = \
 	examples \
 	manuals \
+	charts \
 	$(NULL)

doc/charts/Makefile.am

@@ -0,0 +1,20 @@
+msc: \
+	$(builddir)/hnbgw_context_map.png \
+	$(NULL)
+
+dot: \
+	$(builddir)/hnbgw_context_map_fsm.png \
+	$(builddir)/sccp.png \
+	$(NULL)
+
+$(builddir)/%.png: $(srcdir)/%.msc
+	mscgen -T png -o $@ $<
+
+$(builddir)/%.png: $(srcdir)/%.dot
+	dot -Tpng $< > $@
+
+.PHONY: poll
+# remember current dir: in case the build process removes and recreates the dir, re-enter the new dir
+W := "$(PWD)"
+poll:
+	while true; do $(MAKE) -C $W msc dot; sleep 1; done

doc/charts/hnbgw_context_map.msc

@@ -0,0 +1,107 @@
+msc {
+  hscale="2";
+  hnb[label="HNB"],rua[label="OsmoHNBGW\nRUA FSM / HNBAP"],sccp[label="OsmoHNBGW\nSCCP FSM"],cn[label="CN"];
+
+  hnb <=> rua [label="RANAP/RUA\n(Iuh)"];
+  rua <=> sccp [label="FSM events"];
+  sccp <=> cn [label="RANAP/SCCP/M3UA\n(IuCS, IuPS)"];
+
+  ...;
+  ...;
+  --- [label="Create a new context map (always from HNB)"];
+  hnb => rua [label="RUA Connect\nRANAP InitialUE-Message\nDTAP Location Updating Request"];
+  rua rbox sccp [label="hnbgw_context_map_alloc()"];
+  rua abox rua [label="MAP_RUA_ST_INIT"];
+  sccp abox sccp [label="MAP_SCCP_ST_INIT"];
+  rua rbox rua [label="MAP_RUA_EV_RX_CONNECT\ndata = ranap_msg"];
+  rua abox rua [label="MAP_RUA_ST_CONNECTED"];
+  rua => sccp [label="MAP_SCCP_EV_TX_RANAP_MSG\ndata = ranap_msg"];
+  sccp abox sccp [label="MAP_SCCP_ST_WAIT_CC"];
+  sccp => cn [label="SCCP Connection Request\nRANAP InitialUE-Message\nDTAP Location Updating Request"];
+  ...;
+  sccp <= cn [label="SCCP Connection Confirm"];
+  sccp abox sccp [label="MAP_SCCP_ST_CONNECTED"];
+  --- [label="if SCCP CC with payload"];
+  rua <= sccp [label="MAP_RUA_EV_TX_RANAP_MSG\ndata = ranap_msg"];
+  hnb <= rua [label="RUA DirectTransfer"];
+
+  ...;
+  ...;
+  --- [label="Layer 3 communication"];
+  sccp <= cn [label="SCCP Data Form 1"];
+  rua <= sccp [label="MAP_RUA_EV_TX_RANAP_MSG\ndata = ranap_msg"];
+  hnb <= rua [label="RUA DirectTransfer"];
+  ...;
+  hnb => rua [label="RUA DirectTransfer"];
+  rua => sccp [label="MAP_SCCP_EV_TX_RANAP_MSG\ndata = ranap_msg"];
+  sccp => cn [label="SCCP Data Form 1"];
+
+  ...;
+  ...;
+  --- [label="Usual release"];
+  sccp <= cn [label="SCCP Data Form 1\nIu-ReleaseCommand"];
+  rua <= sccp [label="MAP_RUA_EV_TX_RANAP_MSG\ndata = ranap_msg"];
+  hnb <= rua [label="RUA DirectTransfer\nIu-ReleaseCommand"];
+  ...;
+  hnb => rua [label="RUA Disconnect\nIu-ReleaseComplete"];
+  rua rbox rua [label="MAP_RUA_EV_RX_DISCONNECT"];
+  rua abox rua [label="MAP_RUA_ST_DISCONNECTED"];
+  rua => sccp [label="MAP_SCCP_EV_RAN_DISC\ndata = ranap_msg"];
+  sccp => cn [label="SCCP Data Form 1\nIu-ReleaseComplete\nNOT 'SCCP Released'! See 3GPP TS 48.006 9.2"];
+  sccp abox sccp [label="MAP_SCCP_ST_WAIT_RLSD"];
+  ...;
+  sccp <= cn [label="SCCP Released"];
+  sccp abox sccp [label="MAP_SCCP_ST_DISCONNECTED"];
+  rua rbox sccp [label="map_check_released()"];
+  rua rbox sccp [label="hnbgw_context_map_free()"];
+
+  ...;
+  ...;
+  --- [label="Ungraceful release from CN"];
+  sccp <= cn [label="SCCP Released"];
+  sccp => cn [label="SCCP Release Complete\n(implicit by libosmo-sigtran)"];
+  sccp rbox sccp [label="MAP_SCCP_EV_RX_RELEASED"];
+  sccp note sccp [label="In SCCP there is no \"link loss\".\nIn every case, we will be notified\nvia N-Disconnect prim per SCCP conn."];
+  sccp abox sccp [label="MAP_SCCP_ST_DISCONNECTED"];
+  rua <= sccp [label="MAP_RUA_EV_CN_DISC"];
+  hnb <= rua [label="RUA Disconnect"];
+  rua abox rua [label="MAP_RUA_ST_DISRUPTED"];
+  rua rbox sccp [label="map_check_released()"];
+  rua rbox sccp [label="hnbgw_context_map_free()"];
+
+  ...;
+  ...;
+  ...;
+  --- [label="PCSTATE handling"];
+  sccp << cn [label="N-PCSTATE.indication\npoint-code unreachable"];
+  sccp note sccp [label="currently ignored"];
+
+  ...;
+  ...;
+  --- [label="Ungraceful release from HNB"];
+  hnb -x rua [label="link loss"];
+  rua rbox rua [label="MAP_RUA_EV_HNB_LINK_LOST"];
+  rua abox rua [label="MAP_RUA_ST_DISRUPTED"];
+  rua => sccp [label="MAP_SCCP_EV_RAN_LINK_LOST"];
+  sccp => cn [label="SCCP Released"];
+  sccp abox sccp [label="MAP_SCCP_ST_DISCONNECTED"];
+  rua rbox sccp [label="map_check_released()"];
+  rua rbox sccp [label="hnbgw_context_map_free()"];
+
+  ...;
+  ...;
+  --- [label="Ungraceful release from HNB De-Register"];
+  hnb => rua [label="HNBAP HNB De-Register"];
+  --- [label="or"];
+  hnb => rua [label="HNBAP HNB Register\n(HNB restarted)"];
+  ---;
+  rua rbox rua [label="MAP_RUA_EV_HNB_LINK_LOST"];
+  hnb <= rua [label="RUA Disconnect"];
+  hnb note rua [label="TODO: does it make sense to send\nRUA Disconnect per context when HNB is/was gone?\nOr has the HNB implicitly discarded these?"];
+  rua abox rua [label="MAP_RUA_ST_DISRUPTED"];
+  rua => sccp [label="MAP_SCCP_EV_RAN_LINK_LOST\nfrom map_rua_disrupted_onenter()"];
+  sccp => cn [label="SCCP Released"];
+  sccp abox sccp [label="MAP_SCCP_ST_DISCONNECTED"];
+  rua rbox sccp [label="map_check_released()"];
+  rua rbox sccp [label="hnbgw_context_map_free()"];
+}

doc/charts/hnbgw_context_map_fsm.dot

@@ -0,0 +1,62 @@
+digraph G {
+rankdir=TB
+labelloc=t
+label="hnb_context_map\nRUA and SCCP FSMs"
+
+HNB_connect [label="HNB",shape=box3d]
+rua_to_scu_connect [label="rua_to_scu()",shape=box]
+HNB_DT [label="HNB",shape=box3d]
+rua_to_scu_DT [label="rua_to_scu()",shape=box]
+HNB_DT2 [label="HNB",shape=box3d]
+HNB_disconnect [label="HNB",shape=box3d]
+rua_to_scu_disconnect [label="rua_to_scu()",shape=box]
+CN [shape=box3d]
+CN2 [label="CN",shape=box3d]
+CN3 [label="CN",shape=box3d]
+CN4 [label="CN",shape=box3d]
+
+HNB_connect -> rua_to_scu_connect [label="RUA Connect",style=dotted]
+rua_to_scu_connect -> create [label="(1)",style=dotted]
+create [label="hnbgw_context_map_alloc()",shape=box]
+create -> {RUA_INIT,SCCP_INIT} [label="(1)",style="dashed,bold"]
+
+rua_to_scu_connect -> RUA_CONNECTED [label="(2)\nMAP_RUA_EV_RX_CONNECT",style=dashed]
+RUA_CONNECTED -> SCCP_WAIT_CC [label="(2)\nMAP_SCCP_EV_TX_RANAP_MSG",style=dashed]
+
+RUA_INIT -> RUA_CONNECTED -> RUA_DISCONNECTED [style=bold]
+
+SCCP_INIT -> SCCP_WAIT_CC -> SCCP_CONNECTED -> SCCP_WAIT_RLSD -> SCCP_DISCONNECTED [style=bold]
+SCCP_CONNECTED -> SCCP_DISCONNECTED [label="SCCP RLSD"]
+
+SCCP_WAIT_CC -> CN [label="(2) SCCP CR",style=dotted]
+CN -> SCCP_CONNECTED [label="(3) SCCP CC",style=dashed]
+
+CN4 -> SCCP_CONNECTED [label="(4) SCCP\nData Form 1",style=dotted]
+SCCP_CONNECTED -> RUA_CONNECTED [label="(4)\nMAP_RUA_EV_TX_RANAP_MSG",style=dotted]
+RUA_CONNECTED -> HNB_DT2 [label="(4)\nRUA DirectTransfer",style=dotted]
+
+HNB_DT -> rua_to_scu_DT [label="(5)\nRUA DirectTransfer",style=dotted]
+rua_to_scu_DT -> RUA_CONNECTED [label="(5)\nMAP_RUA_EV_RX_DIRECT_TRANSFER",style=dotted]
+RUA_CONNECTED -> SCCP_CONNECTED [label="(5)\nMAP_SCCP_EV_TX_RANAP_MSG",style=dotted]
+SCCP_CONNECTED -> CN3 [label="(5) SCCP\nData Form 1",style=dotted]
+
+HNB_disconnect -> rua_to_scu_disconnect [label="(6) RUA Id-Disconnect",style=dotted]
+rua_to_scu_disconnect -> RUA_DISCONNECTED [label="(6) MAP_RUA_EV_RX_DISCONNECT",style=dashed]
+RUA_DISCONNECTED -> SCCP_WAIT_RLSD [label="(6) MAP_SCCP_EV_RAN_DISC",style=dashed]
+
+CN2 -> SCCP_DISCONNECTED [label="(7) SCCP RLSD",style=dashed]
+
+{RUA_DISCONNECTED,SCCP_DISCONNECTED} -> release [label="onenter",style="dotted,bold"]
+release [label="map_check_released()",shape=box]
+release -> terminate [label="when both RUA and\nSCCP disconnected",style=dotted]
+terminate [label="hnbgw_context_map_free()",shape=octagon]
+
+subgraph cluster_legend {
+	label=""
+	style=invisible
+	A, B, C, D [style=invisible]
+	A -> B [label="event without\nstate change",style=dotted]
+	C -> D [label="event changes\nstate to...",style=dashed]
+}
+
+}

doc/charts/sccp.dot

@@ -0,0 +1,78 @@
+digraph G {
+rankdir=TB
+labelloc=t; label="SCCP/SS7 use in OsmoHNBGW"
+
+	subgraph cluster_ss0 {
+		label=""
+		ss0 [label="cs7 instance 0\n local pc: 1.1.1"]
+		ss0ab [label="address book"]
+		ss0 -> ss0ab
+
+		msc0a [label="2.2.2"]
+		sgsn0a [label="3.3.3"]
+		msc1a [label="5.5.5"]
+		ss0ab -> msc0a,sgsn0a,msc1a
+	}
+
+	sccp0 [label="hnbgw_sccp_user for '0'\n .osmo_sccp_instance\n .osmo_ss7_user SSN: RANAP"];
+	ss0 -> sccp0 [dir=back]
+
+	msc0 [label="hnbgw_cnlink 'msc0'\n .domain = IuCS\n .sccp_addr -> 2.2.2"]
+	sccp0 -> msc0 [dir=back]
+	msc0a -> msc0 [dir=back]
+
+	cs0 [label="UE CS conn\n hnbgw_context_map"]
+	cs1 [label="UE CS conn\n hnbgw_context_map"]
+	msc0 -> cs0,cs1
+
+	sgsn0 [label="hnbgw_cnlink 'sgsn0'\n .domain = IuPS\n .sccp_addr -> 3.3.3"]
+	sccp0 -> sgsn0 [dir=back]
+	sgsn0a -> sgsn0 [dir=back]
+
+	ps0 [label="UE PS conn\n hnbgw_context_map"]
+	sgsn0 -> ps0
+
+	subgraph cluster_ss1 {
+		label=""
+		ss1 [label="cs7 instance 1\n local pc: 4.4.4"]
+		ss1ab [label="address book"]
+		ss1 -> ss1ab
+
+		sgsn1a [label="6.6.6"]
+		ss1ab -> sgsn1a
+	}
+
+	sccp1 [label="hnbgw_sccp_user for '1'\n .osmo_sccp_instance\n .osmo_ss7_user SSN: RANAP"];
+	ss1 -> sccp1 [dir=back]
+
+	msc1 [label="hnbgw_cnlink 'msc1'\n .domain = IuCS\n .sccp_addr -> 5.5.5"]
+	sccp0 -> msc1 [dir=back]
+	msc1a -> msc1 [dir=back]
+
+	cs2 [label="UE CS conn\n hnbgw_context_map"]
+	msc1 -> cs2
+
+	sgsn1 [label="hnbgw_cnlink 'sgsn1'\n .domain = IuPS\n .sccp_addr -> 6.6.6"]
+	sccp1 -> sgsn1 [dir=back]
+	sgsn1a -> sgsn1 [dir=back]
+
+	ps2 [label="UE PS conn\n hnbgw_context_map"]
+	sgsn1 -> ps2
+
+	subgraph cluster_sccp_inst {
+		label="global sccp.users (llist)"
+		sccp0
+		sccp1
+	}
+
+	subgraph cluster_cnpool_iucs {
+		label="global cnpool_iucs"
+		msc0
+		msc1
+	}
+	subgraph cluster_cnpool_iups {
+		label="global cnpool_iups"
+		sgsn0
+		sgsn1
+	}
+}

doc/examples/osmo-hnbgw/osmo-hnbgw-cnpool.cfg

@@ -0,0 +1,40 @@
+log stderr
+ logging filter all 1
+ logging color 1
+ logging print category-hex 0
+ logging print category 1
+ logging timestamp 0
+ logging print file basename last
+ logging print level 1
+ logging level set-all notice
+
+cs7 instance 0
+ point-code 0.42.0
+
+ sccp-address my-msc-0
+  point-code 0.1.0
+ sccp-address my-msc-1
+  point-code 0.1.1
+ sccp-address my-sgsn-0
+  point-code 0.2.0
+
+hnbgw
+ plmn 001 01
+ iucs
+  nri bitlen 10
+  nri null add 0 7
+ iups
+  nri bitlen 8
+  nri null add 0 5
+
+msc 0
+ remote-addr my-msc-0
+ nri add 128 255
+
+msc 1
+ remote-addr my-msc-1
+ nri add 256 511
+
+sgsn 0
+ remote-addr my-sgsn-0
+ nri add 128 255

doc/examples/osmo-hnbgw/osmo-hnbgw-cs7.cfg

@@ -0,0 +1,29 @@
+cs7 instance 0
+ point-code 0.3.0
+ asp asp-clnt-hnbgw-0 2905 0 m3ua
+  remote-ip 127.0.0.1
+  role asp
+  sctp-role client
+ sccp-address my-msc
+  point-code 1.2.3
+ sccp-address my-sgsn
+  point-code 1.4.2
+
+hnbgw
+ plmn 001 01
+ iuh
+  local-ip 0.0.0.0
+msc 0
+ remote-addr my-msc
+sgsn 0
+ remote-addr my-sgsn
+
+log stderr
+ logging filter all 1
+ logging color 1
+ logging print category-hex 0
+ logging print category 1
+ logging timestamp 0
+ logging print file basename last
+ logging print level 1
+ logging level set-all notice

doc/examples/osmo-hnbgw/osmo-hnbgw-pfcp.cfg

@@ -0,0 +1,21 @@
+log stderr
+ logging filter all 1
+ logging color 1
+ logging print category-hex 0
+ logging print category 1
+ logging timestamp 0
+ logging print file basename last
+ logging print level 1
+ logging level set-all notice
+hnbgw
+ plmn 001 01
+ iuh
+  local-ip 0.0.0.0
+ mgw 0
+  remote-ip 127.0.0.1
+  local-port 2729
+  remote-port 2427
+  reset-endpoint rtpbridge/*
+ pfcp
+  remote-addr 127.0.0.2
+  local-addr 127.0.0.1

doc/examples/osmo-hnbgw/osmo-hnbgw.cfg

@@ -1,25 +1,19 @@
-!
-! OsmoHNBGW (0) configuration saved from vty
-!!
-!
 log stderr
  logging filter all 1
  logging color 1
+ logging print category-hex 0
  logging print category 1
- logging timestamp 1
- logging print extended-timestamp 1
- logging level all debug
- logging level lglobal notice
- logging level llapd notice
- logging level linp notice
- logging level lmux notice
- logging level lmi notice
- logging level lmib notice
- logging level lsms notice
- logging level lctrl notice
- logging level lgtp notice
- logging level lstats notice
+ logging timestamp 0
+ logging print file basename last
+ logging print level 1
+ logging level set-all notice
 hnbgw
+ plmn 001 01
  iuh
   local-ip 0.0.0.0
-  hnbap-allow-tmsi 1
+ mgw 0
+  remote-ip 127.0.0.1
+  local-port 2729
+  remote-port 2427
+  reset-endpoint rtpbridge/*
+

doc/manuals/chapters/overview.adoc

@@ -9,22 +9,62 @@ OsmoHNBGW implements the Home NodeB Gateway function in the 3G network architect
 as a gateway between the classic 3G core network (CN) domain with its IuCS and IuPS interface
 and the femtocell based RAN.
 
-A typical 3G network consisting of Osmocom components will look as illustrated in the following
+A typical 3G network consisting of Osmocom components is illustrated in the following
 diagram:
 
 [[fig-3g]]
 .Typical 3G network architecture used with OsmoHNBGW
+[graphviz]
 ----
-        +------------+           +--------+          +----------+          +---------+
- UE <-->| hNodeB     |<--Iuh---->| HNB-GW |<--IuCS-->| OsmoMSC  |<--GSUP-->| OsmoHLR |
- UE <-->| femto cell |     ...-->|        |    ...-->|          |          |         |
-        |            |           |        |          +----------+          +---------|
-        +------------+<--GTP-U   |        |
-                              \  |        |          +------+           +------+
-                              |  |        |<--IuPS-->| SGSN |<--GTP-C-->| GGSN |
-                              |  +--------+    ...-->|      |   GTP-U-->|      |
-                              |                      +------+  /        +------+
-                              \_______________________________/
+digraph G {
+  rankdir = LR;
+
+  UE [label="UE\n(3G phone)"]
+  PBX [label="PBX\nAsterisk, FreeSwitch,\nKamailio, Yate, ..."]
+
+  subgraph cluster_msc_mgw {
+    style=dotted
+    MSC
+    MGW1 [label="MGW"]
+    MSC -> MGW1 [label="MGCP",constraint=false]
+  }
+
+  subgraph cluster_hnbgw_mgw_upf {
+    style=dotted
+    MGW3 [label="MGW"]
+    UPF
+    HNBGW [label=HNBGW,style=bold]
+    HNBGW -> MGW3 [label="MGCP",constraint=false]
+    HNBGW -> UPF [label="PFCP",constraint=false]
+  }
+
+  hNodeB [shape="box",label="hNodeB\n(3G femto cell)"]
+
+  MSC -> HLR [label="\nGSUP",style=bold]
+  SGSN -> HLR [label="GSUP",style="dashed,bold"]
+  UE -> hNodeB [label="Uu",style=bold]
+  UE -> hNodeB [style="dashed,bold"]
+  hNodeB -> HNBGW [label="Iuh",style="bold"]
+  STP2 [label="STP\n(SCCP/M3UA)"]
+  HNBGW -> STP2 -> SGSN [label="IuPS",style="dashed,bold"]
+  HNBGW -> STP2 -> MSC [label="IuCS",style="bold"]
+  SGSN -> GGSN [label="GTP-C",style="dashed,bold"]
+  hNodeB -> UPF -> GGSN [label="GTP-U(3G)",style="dashed"]
+  GGSN -> internet [label="tun",style="dashed"]
+
+  hNodeB -> MGW3 [label="IuUP/RTP",constraint=false]
+  MGW3 -> MGW1 [label="IuUP/RTP"]
+
+  MSC -> SIPConnector [label="MNCC socket",style=bold]
+
+  SIPConnector -> PBX [label="SIP",style=bold]
+  MGW1 -> PBX [label="RTP"]
+
+  A, B, C, D [style="invisible"]
+  A -> B [label="data (PS)",style="dashed"]
+  C -> D [label="voice/SMS/USSD (CS)"]
+
+}
 ----
 
 The HNB-GW performs a translation interface between the IuCS/IuPS interfaces on the one hand
@@ -32,17 +72,18 @@ side, and the Iuh interface on the or ther hand:
 
 ----
                       Iuh                         IuCS/IuPS
-
-NAS                   +----+----+                 +----+----+
-Non-Access Stratum    | CC | MM |                 | CC | MM |
-- - - - - - - - - - - +----+----+-------+         +----+----+
-                      | RANAP   |       |    H    | RANAP   |
-Access Stratum        +---------+ HNBAP |    N    +---------+ - - SCCP USER SAP
-                      | RUA     |       |    B    | SUA     |  \
-                      +---------+-------+    -    +---------+  |
-                      |        SCTP     |    G    | SCTP    |  } SIGTRAN
-                      +-----------------+    W    +---------+  |
-                      |        IP       |         | IP      |  /
+                                                  +----+----+
+                                                  | CC | MM |
+NAS                   +----+----+            .  . +----+----+
+Non-Access Stratum    | CC | MM |         .       | RANAP   |
+- - - - - - - - - - - +----+----+-------+         +---------+
+                      | RANAP   |       |    H    | SCCP    |
+Access Stratum        +---------+ HNBAP |    N    +---------+
+                      | RUA     |       |    B    | M3UA    |
+                      +---------+-------+    -    +---------+
+                      |        SCTP     |    G    | SCTP    |
+                      +-----------------+    W    +---------+
+                      |        IP       |         | IP      |
                       +-----------------+         +---------+
 ----
 

doc/manuals/chapters/running.adoc

@@ -69,11 +69,30 @@ specific interface, and will hence not encounter conflicts for multiple instance
 running on the same interface:
 
 - The SCCP/M3UA links are established by OsmoHNBGW contacting an STP.
+- The MGCP link is established by OsmoHNBGW contacting an MGW.
+- The PFCP link is established by OsmoHNBGW contacting a UPF.
 
 To run multiple OsmoHNBGW instances on the same SCCP routing, each HNBGW has to
 configure a distinct point-code, see <<configure_iucs_iups>>.
 
 
+=== Configure limits
+
+When connecting hundreds of HNB to OsmoHNBGW, it may be necessary to adjust the
+operating system's limit on open file descriptors for the osmo-hnbgw process. A
+typical default limit imposed by operating systems is 1024; this would be
+exceeded by, for example, about 1024 HNB on Iuh, sockets for other interfaces
+not considered yet.
+
+It should be ok to set an OS limit on open file descriptors as high as 65536
+for osmo-hnbgw, which practically rules out failure from running out of file
+descriptors anywhere (<50,000 HNB).
+
+When using systemd, the file descriptor limit may be adjusted in the service
+file by the `LimitNOFILE` setting ("Number of Open FILE descriptors").
+OsmoHNBGW ships a systemd service file with a high LimitNOFILE setting.
+
+
 === Configuring Primary Links
 
 [[configure_iucs_iups]]
@@ -117,3 +136,75 @@ hnbgw
   local-ip 10.9.8.7
   local-port 29169
 ----
+
+==== Configure co-located media gateway
+
+OsmoHNBGW requires a co-located OsmoMGW instance. The purpose of the co-located
+media gateway is to relay the RTP traffic between hNodeB and the core network.
+
+For security reasons the RAN network is kept separate and isolated from the
+core network. Both networks will usually have no transparent routing in between
+them. The co-located media gateway provides an interface between hNodeB and core
+network across this boundary.
+
+The configuration is done under the hnbgw node along with `iucs` and `iups`.
+
+An example configuration for OsmoHNBGW's MGCP client:
+
+----
+hnbgw
+ mgw 0
+  remote-ip 127.0.0.1
+  remote-port 2427
+  reset-endpoint rtpbridge/* <1>
+----
+<1> The 'reset-endpoint' setting instructs the OsmoMGW to send a wildcarded
+DLCX to the media gateway. This helps to clear lingering calls from the
+media gateway when the OsmoHNBGW is restarted.
+
+OsmoHNBGW is also able to handle a pool of media gateways for load
+distribution. See also <<mgw_pooling>>.
+
+[NOTE]
+====
+Previous versions of OsmoHNBGW didn't have the 'mgw' VTY node and
+hence didn't support the MGW pooling feature. Therefore, historically the MGW
+related commands where placed under the `mgcp` VTY node. The MGW related commands
+under the `mgcp` VTY are still parsed and used but its use is deprecated and
+hence discouraged in favour of the new `mgw` node. Writing the config to a file
+from within OsmoHNBGW will automatically convert the config to use the new `mgw`
+node.
+====
+
+==== Configure co-located User Plane Function
+
+OsmoHNBGW optionally supports relaying the GTP user plane via a co-located UPF,
+which is controlled by the PFCP protocol.
+
+PFCP support is optional at compile time, as well as run time. To use a co-located UPF,
+
+* osmo-hnbgw needs to be compiled with 'configure --enable-pfcp',
+* and osmo-hnbgw.cfg needs to configure a 'pfcp' / 'remote-addr' and
+  'local-addr'.
+
+The following example configures OsmoHNBGW to associate via PFCP with a UPF
+listening on UDP 127.0.0.2:8805, ready to setup GTP tunnel relays.
+
+----
+hnbgw
+ pfcp
+  remote-addr 127.0.0.2
+  local-addr 127.0.0.1
+----
+
+3GPP TS 29.244 4.2.2 specifies that PFCP Request messages shall be sent to UDP
+port 8805, i.e. the PFCP port is fixed as 8805 and currently not configurable in
+osmo-hnbgw.
+
+Setting a 'local-addr' is required: the PFCP protocol features a Node ID, which
+uniquely identifies PFCP peers across different interfaces. According to the
+PFCP specification, the Node ID can be a fully-qualified domain name (FQDN) or
+an IP address. Currently, osmo-hnbgw has no support for using an FQDN as Node
+ID, and so far uses the 'local-addr' as local Node ID -- hence the 'local-addr'
+must not be "0.0.0.0", which is an unfortunate consequence. This is likely to
+improve in the future, see https://osmocom.org/issues/5647 .

doc/manuals/osmohnbgw-usermanual.adoc

@@ -22,8 +22,12 @@ include::./common/chapters/vty.adoc[]
 
 include::./common/chapters/logging.adoc[]
 
+include::./common/chapters/sigtran.adoc[]
+
 include::./common/chapters/cs7-config.adoc[]
 
+include::./common/chapters/mgwpool.adoc[]
+
 // include::{srcdir}/chapters/net.adoc[]
 
 // include::./common/chapters/control_if.adoc[]

include/osmocom/hnbgw/Makefile.am

@@ -1,4 +1,22 @@
 noinst_HEADERS = \
+	cnlink.h \
+	context_map.h \
+	hnb.h \
+	hnb_persistent.h \
+	hnbgw.h \
+	hnbgw_cn.h \
+	hnbgw_hnbap.h \
+	hnbgw_pfcp.h \
+	hnbgw_ranap.h \
+	hnbgw_rua.h \
+	hnbgw_sccp.h \
+	kpi.h \
+	mgw_fsm.h \
+	nft_kpi.h \
+	ps_rab_ass_fsm.h \
+	ps_rab_fsm.h \
+	ranap_rab_ass.h \
+	tdefs.h \
+	umts_cell_id.h \
 	vty.h \
-	context_map.h hnbgw.h hnbgw_cn.h \
-	hnbgw_hnbap.h hnbgw_rua.h hnbgw_ranap.h
+	$(NULL)

include/osmocom/hnbgw/cnlink.h

@@ -0,0 +1,138 @@
+#pragma once
+
+#include <stdbool.h>
+
+#include <osmocom/core/rate_ctr.h>
+#include <osmocom/core/stat_item.h>
+#include <osmocom/gsm/gsm48.h>
+
+#include <osmocom/sigtran/sccp_sap.h>
+
+#include <osmocom/ranap/ranap_ies_defs.h>
+
+#include <osmocom/hnbgw/hnbgw_sccp.h>
+
+struct hnbgw_cnpool;
+
+enum hnbgw_cnlink_ctr {
+	/* TODO: basic counters completely missing
+	 * ...
+	 */
+	CNLINK_CTR_RANAP_RX_UDT_RESET,
+	CNLINK_CTR_RANAP_RX_UDT_RESET_ACK,
+	CNLINK_CTR_RANAP_RX_UDT_PAGING,
+	CNLINK_CTR_RANAP_RX_UDT_UNKNOWN,
+	CNLINK_CTR_RANAP_RX_UDT_UNSUPPORTED,
+	CNLINK_CTR_RANAP_RX_UDT_OVERLOAD_IND,
+	CNLINK_CTR_RANAP_RX_UDT_ERROR_IND,
+
+	CNLINK_CTR_RANAP_TX_UDT_RESET,
+	CNLINK_CTR_RANAP_TX_UDT_RESET_ACK,
+
+	/* SCCP Counters: */
+	CNLINK_CTR_SCCP_N_UNITDATA_REQ,
+	CNLINK_CTR_SCCP_N_UNITDATA_IND,
+	CNLINK_CTR_SCCP_N_NOTICE_IND,
+	CNLINK_CTR_SCCP_N_CONNECT_REQ,
+	CNLINK_CTR_SCCP_N_CONNECT_CNF,
+	CNLINK_CTR_SCCP_N_DATA_REQ,
+	CNLINK_CTR_SCCP_N_DATA_IND,
+	CNLINK_CTR_SCCP_N_DISCONNECT_REQ,
+	CNLINK_CTR_SCCP_N_DISCONNECT_IND,
+	CNLINK_CTR_SCCP_N_PCSTATE_IND,
+	CNLINK_CTR_SCCP_RLSD_CN_ORIGIN,
+
+	/* Counters related to link selection from a CN pool. */
+	CNLINK_CTR_CNPOOL_SUBSCR_NEW,
+	CNLINK_CTR_CNPOOL_SUBSCR_REATTACH,
+	CNLINK_CTR_CNPOOL_SUBSCR_KNOWN,
+	CNLINK_CTR_CNPOOL_SUBSCR_PAGED,
+	CNLINK_CTR_CNPOOL_SUBSCR_ATTACH_LOST,
+	CNLINK_CTR_CNPOOL_EMERG_FORWARDED,
+};
+#define CNLINK_CTR_INC(cnlink, x) rate_ctr_inc2((cnlink)->ctrs, x)
+
+enum cnlink_stat {
+	CNLINK_STAT_CONNECTED,
+};
+#define CNLINK_STAT(cnlink, x) osmo_stat_item_group_get_item((cnlink)->statg, x)
+#define CNLINK_STAT_SET(cnlink, x, val) osmo_stat_item_set(CNLINK_STAT(cnlink, x), val)
+
+/* User provided configuration for struct hnbgw_cnlink. */
+struct hnbgw_cnlink_cfg {
+	/* cs7 address book entry to indicate both the remote point-code of the peer, as well as which cs7 instance to
+	 * use. */
+	char *remote_addr_name;
+
+	struct osmo_nri_ranges *nri_ranges;
+};
+
+/* A CN peer, like 'msc 0' or 'sgsn 23' */
+struct hnbgw_cnlink {
+	struct llist_head entry;
+
+	/* backpointer to CS or PS CN pool. */
+	struct hnbgw_cnpool *pool;
+
+	struct osmo_fsm_inst *fi;
+
+	int nr;
+
+	struct hnbgw_cnlink_cfg vty;
+	struct hnbgw_cnlink_cfg use;
+
+	/* To print in logging/VTY */
+	char *name;
+
+	/* Copy of the address book entry use.remote_addr_name. */
+	struct osmo_sccp_addr remote_addr;
+
+	/* The SCCP instance for the cs7 instance indicated by remote_addr_name. (Multiple hnbgw_cnlinks may use the
+	 * same hnbgw_sccp_user -- there is exactly one hnbgw_sccp_user per configured cs7 instance.) */
+	struct hnbgw_sccp_user *hnbgw_sccp_user;
+
+	/* linked list of hnbgw_context_map */
+	struct llist_head map_list;
+
+	bool allow_attach;
+	bool allow_emerg;
+	struct llist_head paging;
+
+	struct rate_ctr_group *ctrs;
+	struct osmo_stat_item_group *statg;
+};
+
+struct hnbgw_cnlink *hnbgw_cnlink_alloc(struct hnbgw_cnpool *cnpool, int nr);
+void hnbgw_cnlink_term_and_free(struct hnbgw_cnlink *cnlink);
+void hnbgw_cnlink_drop_sccp(struct hnbgw_cnlink *cnlink);
+int hnbgw_cnlink_set_name(struct hnbgw_cnlink *cnlink, const char *name);
+int hnbgw_cnlink_tx_ranap_reset(struct hnbgw_cnlink *cnlink);
+int hnbgw_cnlink_tx_ranap_reset_ack(struct hnbgw_cnlink *cnlink);
+
+int hnbgw_cnlink_start_or_restart(struct hnbgw_cnlink *cnlink);
+
+char *hnbgw_cnlink_sccp_addr_to_str(struct hnbgw_cnlink *cnlink, const struct osmo_sccp_addr *addr);
+
+static inline struct osmo_sccp_instance *hnbgw_cnlink_sccp(const struct hnbgw_cnlink *cnlink)
+{
+	if (!cnlink)
+		return NULL;
+	if (!cnlink->hnbgw_sccp_user)
+		return NULL;
+	return hnbgw_sccp_user_get_sccp_instance(cnlink->hnbgw_sccp_user);
+}
+
+/* cnlink_fsm.c related: */
+extern struct osmo_fsm cnlink_fsm;
+bool cnlink_is_conn_ready(const struct hnbgw_cnlink *cnlink);
+void cnlink_rx_reset_cmd(struct hnbgw_cnlink *cnlink);
+void cnlink_rx_reset_ack(struct hnbgw_cnlink *cnlink);
+void cnlink_resend_reset(struct hnbgw_cnlink *cnlink);
+void cnlink_set_disconnected(struct hnbgw_cnlink *cnlink);
+
+/* cnlink_paging.c related: */
+const char *cnlink_paging_add_ranap(struct hnbgw_cnlink *cnlink, const RANAP_PagingIEs_t *paging_ies);
+struct hnbgw_cnlink *cnlink_find_by_paging_mi(struct hnbgw_cnpool *cnpool, const struct osmo_mobile_identity *mi);
+
+#define LOG_CNLINK(CNLINK, SUBSYS, LEVEL, FMT, ARGS...) \
+	LOGP(SUBSYS, LEVEL, "(%s) " FMT, (CNLINK) ? (CNLINK)->name : "null", ##ARGS)

include/osmocom/hnbgw/context_map.h

@@ -2,13 +2,103 @@
 
 #include <stdint.h>
 #include <osmocom/core/linuxlist.h>
+#include <osmocom/core/utils.h>
+#include <osmocom/hnbgw/hnb.h>
+#include <osmocom/hnbgw/hnbgw.h>
+#include <osmocom/gsm/gsm48.h>
 
+#define LOG_MAP(HNB_CTX_MAP, SUBSYS, LEVEL, FMT, ARGS...) \
+	LOGHNB((HNB_CTX_MAP) ? (HNB_CTX_MAP)->hnb_ctx : NULL, \
+	       SUBSYS, LEVEL, "RUA-%u SCCP-%u %s MI=%s%s%s: " FMT, \
+	       (HNB_CTX_MAP) ? (HNB_CTX_MAP)->rua_ctx_id : 0, \
+	       (HNB_CTX_MAP) ? (HNB_CTX_MAP)->scu_conn_id : 0, \
+	       (HNB_CTX_MAP) ? \
+			((HNB_CTX_MAP)->cnlink ? (HNB_CTX_MAP)->cnlink->name \
+			  : ((HNB_CTX_MAP)->is_ps ? "PS" : "CS")) \
+			: "NULL", \
+	       (HNB_CTX_MAP) ? osmo_mobile_identity_to_str_c(OTC_SELECT, &(HNB_CTX_MAP)->l3.mi) : "null", \
+	       (HNB_CTX_MAP) && (HNB_CTX_MAP)->l3.from_other_plmn ? " (from other PLMN)" : "", \
+	       (HNB_CTX_MAP) && (HNB_CTX_MAP)->l3.is_emerg ? " EMERGENCY" : "", \
+	       ##ARGS)
+
+/* All these events' data argument may either be NULL, or point to a RANAP msgb.
+ * - The msgb shall be in the OTC_SELECT talloc pool, so that they will be deallocated automatically. Some events
+ *   processing will store the msgb for later, in which case it will take over ownership of the msgb by means of
+ *   talloc_steal().
+ * - For events that may send a RANAP message towards CN via SCCP, the msgb shall have reserved headroom to fit a struct
+ *   osmo_scu_prim. These are: MAP_RUA_EV_RX_*.
+ * - The RANAP message shall be at msgb_l2().
+ */
+enum map_rua_fsm_event {
+	/* Receiving a RUA Connect from HNB.
+	 * Parameter: struct msgb *ranap_msg */
+	MAP_RUA_EV_RX_CONNECT,
+	/* Receiving some data from HNB via RUA, to forward via SCCP to CN.
+	 * Parameter: struct msgb *ranap_msg */
+	MAP_RUA_EV_RX_DIRECT_TRANSFER,
+	/* Receiving a RUA Disconnect from HNB.
+	 * Parameter: struct msgb *ranap_msg (can be NULL) */
+	MAP_RUA_EV_RX_DISCONNECT,
+	/* SCCP has received some data from CN to forward via RUA to HNB.
+	 * Parameter: struct msgb *ranap_msg */
+	MAP_RUA_EV_TX_DIRECT_TRANSFER,
+	/* The CN side is disconnected (e.g. received an SCCP Released), that means we are going gracefully disconnect
+	 * RUA, too. */
+	MAP_RUA_EV_CN_DISC,
+	/* All of a sudden, there is no RUA link. For example, HNB vanished / restarted, or SCTP SHUTDOWN on the RUA
+	 * link. Skip RUA disconnect. */
+	MAP_RUA_EV_HNB_LINK_LOST,
+};
+
+/* All these events' data argument is identical to enum map_rua_fsm_event, with this specialisation:
+ * - The events that may send a RANAP message towards CN via SCCP and hence require a headroom for an osmo_scu_prim are:
+ *   MAP_SCCP_EV_TX_DATA_REQUEST, MAP_SCCP_EV_RAN_DISC.
+ */
+enum map_sccp_fsm_event {
+	/* Receiving an SCCP CC from CN.
+	 * Parameter: struct msgb *ranap_msg, may be NULL or empty. */
+	MAP_SCCP_EV_RX_CONNECTION_CONFIRM,
+	/* Receiving some data from CN via SCCP, to forward via RUA to HNB.
+	 * Parameter: struct msgb *ranap_msg, may be NULL or empty. */
+	MAP_SCCP_EV_RX_DATA_INDICATION,
+	/* RUA has received some data from HNB to forward via SCCP to CN.
+	 * Parameter: struct msgb *ranap_msg. */
+	MAP_SCCP_EV_TX_DATA_REQUEST,
+	/* 3GPP TS 25.468 9.1.5: The RAN side received a RUA Disconnect.
+	 * - Under normal conditions (cause=Normal) the RUA Disconnect contains a RANAP Iu-ReleaseComplete.
+	 *   On SCCP, the Iu-ReleaseComplete should still be forwarded as N-Data SCCP Data Form 1),
+	 *   and we will expect the CN to send an SCCP RLSD soon. Hence, give CN a chance to send an SCCP RLSD;
+	 *   after a timeout we will send a non-standard RLSD to the CN instead.
+	 * - Under error conditions, cause!=Normal and there's no RANAP message.
+	 *   In that case, we need to tear down the associated SCCP link towards CN with an RLSD,
+	 *   which in turn will tear down the upper layer Iu conn.
+	 *
+	 * Parameter: bool rua_disconnect_err_condition, whether the disconnect
+	 *	      happened under error or normal conditions, as per the above.
+	 */
+	MAP_SCCP_EV_RAN_DISC,
+	/* The RAN released ungracefully. We will directly disconnect the SCCP connection, too.
+	 * Parameter: no parameter, NULL. */
+	MAP_SCCP_EV_RAN_LINK_LOST,
+	/* Receiving an SCCP RLSD from CN, or libosmo-sigtran tells us about SCCP connection timeout. All done.
+	 * Parameter: struct msgb *ranap_msg, may be NULL or empty. */
+	MAP_SCCP_EV_RX_RELEASED,
+	/* The human admin asks to drop the current SCCP connection, by telnet VTY 'apply sccp' in presence of SCCP
+	 * config changes.
+	 * Parameter: no parameter, NULL. */
+	MAP_SCCP_EV_USER_ABORT,
+	/* The CN link can no longer work, for example a RANAP RESET was received from the cnlink that hosts this
+	 * context map.
+	 * Parameter: no parameter, NULL. */
+	MAP_SCCP_EV_CN_LINK_LOST,
+};
+
+/* For context_map_get_state(), to combine the RUA and SCCP states, for VTY reporting only. */
 enum hnbgw_context_map_state {
-	MAP_S_NULL,
-	MAP_S_ACTIVE,		/* currently active map */
-	MAP_S_RESERVED1,	/* just disconnected, still resrved */
-	MAP_S_RESERVED2,	/* still reserved */
-	MAP_S_NUM_STATES	/* Number of states, keep this at the end */
+	MAP_S_CONNECTING,       /* not active yet; effectively waiting for SCCP CC */
+	MAP_S_ACTIVE,           /* both RUA and SCCP are connected */
+	MAP_S_DISCONNECTING,    /* not active anymore; effectively waiting for SCCP RLSD */
+	MAP_S_NUM_STATES        /* Number of states, keep this at the end */
 };
 
 extern const struct value_string hnbgw_context_map_state_names[];
@@ -18,34 +108,141 @@ static inline const char *hnbgw_context_map_state_name(enum hnbgw_context_map_st
 struct hnb_context;
 struct hnbgw_cnlink;
 
-struct hnbgw_context_map {
-	/* entry in the per-CN list of mappings */
-	struct llist_head cn_list;
-	/* entry in the per-HNB list of mappings */
-	struct llist_head hnb_list;
-	/* pointer to HNB */
-	struct hnb_context *hnb_ctx;
-	/* pointer to CN */
-	struct hnbgw_cnlink *cn_link;
-	/* RUA contxt ID */
-	uint32_t rua_ctx_id;
-	/* False for CS, true for PS */
-	bool is_ps;
-	/* SCCP User SAP connection ID */
-	uint32_t scu_conn_id;
-
-	enum hnbgw_context_map_state state;
+struct hnbgw_l3_peek {
+	/* L3 message type, like GSM48_PDISC_MM+GSM48_MT_MM_LOC_UPD_REQUEST... / GSM48_PDISC_MM_GPRS+GSM48_MT_GMM_ATTACH_REQ... */
+	uint8_t gsm48_pdisc;
+	uint8_t gsm48_msg_type;
+	/* The Mobile Identity from MM and GMM messages */
+	struct osmo_mobile_identity mi;
+	/* On PS, the "TMSI Based NRI Container", 10 bit integer, or -1 if not present.
+	 * This is only for PS -- for CS, the NRI is in the TMSI obtained from 'mi' above. */
+	int gmm_nri_container;
+	/* For a CM Service Request for voice call, true if this is for an Emergency Call, false otherwise. */
+	bool is_emerg;
+	/* True if the NAS PDU indicates that the UE was previously attached to a different PLMN than the local PLMN. */
+	bool from_other_plmn;
 };
 
+/* used in hnbgw_context_map.rab_state[] */
+enum rab_state {
+	RAB_STATE_INACTIVE,
+	RAB_STATE_ACT_REQ,
+	RAB_STATE_ACTIVE,
+	RAB_STATE_REL_REQ,
+};
+extern const struct value_string hnbgw_rab_state_names[];
+static inline const char *hnbgw_rab_state_name(enum rab_state val)
+{ return get_value_string(hnbgw_rab_state_names, val); }
 
-struct hnbgw_context_map *
-context_map_alloc_by_hnb(struct hnb_context *hnb, uint32_t rua_ctx_id,
-			 bool is_ps,
-			 struct hnbgw_cnlink *cn_if_new);
 
-struct hnbgw_context_map *
-context_map_by_cn(struct hnbgw_cnlink *cn, uint32_t scu_conn_id);
+struct hnbgw_context_map {
+	/* entry in the per-CN list of mappings */
+	struct llist_head hnbgw_cnlink_entry;
+	/* entry in the per-HNB list of mappings. If hnb_ctx == NULL, then this llist entry has been llist_del()eted and
+	 * must not be used. */
+	struct llist_head hnb_list;
 
-void context_map_deactivate(struct hnbgw_context_map *map);
+	/* entry in the per-SCCP-conn-id hashtable */
+	struct hlist_node hnbgw_sccp_user_entry;
 
-int context_map_init(struct hnb_gw *gw);
+	/* Pointer to HNB for this map, to transceive RUA. If the HNB has disconnected without releasing the RUA
+	 * context, this is NULL. */
+	struct hnb_context *hnb_ctx;
+	/* RUA context ID used in RUA messages to/from the hnb_gw. */
+	uint32_t rua_ctx_id;
+	/* FSM handling the RUA state for rua_ctx_id. */
+	struct osmo_fsm_inst *rua_fi;
+
+	/* State context related to field rua_fi above: */
+	struct {
+		/* Whether RUA Disconnect received from HNB happened as a normal condition or an error/abnormal condition.
+		* This is known based on cause and/or RANAP message included in the RUA
+		* Disconnect message, and tells us whether we should immediately
+		* terminate the related SCCP session or wait for CN to finish it.
+		* Defaults to false, only set to true explicitly when needed. */
+		bool rua_disconnect_err_condition;
+	} rua_fi_ctx;
+
+	/* Pointer to CN, to transceive SCCP. */
+	struct hnbgw_cnlink *cnlink;
+	/* SCCP User SAP connection ID used in SCCP messages to/from the cn_link. */
+	uint32_t scu_conn_id;
+	/* FSM handling the SCCP state for scu_conn_id. */
+	struct osmo_fsm_inst *sccp_fi;
+	/* State context related to field sccp_fi above: */
+	struct {
+		/* List of cached packets received from RUA and to be forwarded
+		once SCCP CReq is CC'ed and move to CONNECTED state. */
+		struct llist_head wait_cc_tx_msg_list;
+	} sccp_fi_ctx;
+
+	/* False for CS, true for PS */
+	bool is_ps;
+
+	/* Information extracted from RUA Connect's RANAP InitialUE message */
+	struct hnbgw_l3_peek l3;
+
+	/* When an FSM is asked to disconnect but must still wait for a response, it may set this flag, to continue to
+	 * disconnect once the response is in. In particular, when SCCP is asked to disconnect after an SCCP Connection
+	 * Request was already sent and while waiting for a Connection Confirmed, we should still wait for the SCCP CC
+	 * and immediately release it after that, to not leak the connection. */
+	bool please_disconnect;
+
+	/* FSM instance for the MGW, handles the async MGCP communication necessary to intercept CS RAB Assignment and
+	 * redirect the RTP via the MGW. */
+	struct osmo_fsm_inst *mgw_fi;
+
+	/* FSMs handling RANAP RAB assignments for PS, list of struct ps_rab_ass. They handle the async PFCP
+	 * communication necessary to intercept PS RAB Assignment and redirect the GTP via the UPF.
+	 *
+	 * For PS RAB Assignment, each Request gets one ps_rab_ass FSM and each Response gets one ps_rab_ass FSM.
+	 * The reason is that theoretically, each such message can contain any number and any combination of RAB IDs,
+	 * and Request and Response don't necessarily match the RAB IDs contained. In practice I only ever see a single
+	 * RAB matching in Request and Response, but we cannot rely on that to always be true.
+	 *
+	 * The state of each RAB's PFCP negotiation is kept separately in the field ps_rab_list, and as soon as all RABs
+	 * appearing in a PS RAB Assignment message have completed their PFCP setup, we can replace the GTP info for the
+	 * RAB IDs and forward the RAB Assignment Request to HNB / the RAB Assignment Response to CN.
+	 */
+	struct llist_head ps_rab_ass_list;
+
+	/* All PS RABs and their GTP tunnel mappings. list of struct ps_rab. Each ps_rab FSM handles the PFCP
+	 * communication for one particular RAB ID. */
+	struct llist_head ps_rab_list;
+
+	/* RAB state tracking. As RAB-ID is an 8-bit integer, we need 256 elements in the array */
+	uint8_t rab_state[256];
+
+	/* Flag to prevent calling context_map_free() from cleanup code paths triggered by context_map_free() itself. */
+	bool deallocating;
+};
+
+enum hnbgw_context_map_state context_map_get_state(struct hnbgw_context_map *map);
+enum hnbgw_context_map_state map_rua_get_state(struct hnbgw_context_map *map);
+enum hnbgw_context_map_state map_sccp_get_state(struct hnbgw_context_map *map);
+
+struct hnbgw_context_map *context_map_find_by_rua_ctx_id(struct hnb_context *hnb, uint32_t rua_ctx_id, bool is_ps);
+struct hnbgw_context_map *context_map_alloc(struct hnb_context *hnb, uint32_t rua_ctx_id, bool is_ps);
+int context_map_set_cnlink(struct hnbgw_context_map *map, struct hnbgw_cnlink *cnlink_selected);
+
+void map_rua_fsm_alloc(struct hnbgw_context_map *map);
+void map_sccp_fsm_alloc(struct hnbgw_context_map *map);
+
+void context_map_hnb_released(struct hnbgw_context_map *map);
+
+#define map_rua_dispatch(MAP, EVENT, MSGB) \
+	_map_rua_dispatch(MAP, EVENT, MSGB, __FILE__, __LINE__)
+int _map_rua_dispatch(struct hnbgw_context_map *map, uint32_t event, struct msgb *ranap_msg,
+		      const char *file, int line);
+
+#define map_sccp_dispatch(MAP, EVENT, MSGB) \
+	_map_sccp_dispatch(MAP, EVENT, MSGB, __FILE__, __LINE__)
+int _map_sccp_dispatch(struct hnbgw_context_map *map, uint32_t event, struct msgb *ranap_msg,
+		       const char *file, int line);
+
+bool map_rua_is_active(struct hnbgw_context_map *map);
+bool map_sccp_is_active(struct hnbgw_context_map *map);
+void context_map_cnlink_lost(struct hnbgw_context_map *map);
+void context_map_free(struct hnbgw_context_map *map);
+
+unsigned int msg_has_l2_data(const struct msgb *msg);

include/osmocom/hnbgw/hnb.h

@@ -0,0 +1,76 @@
+#pragma once
+
+#include <osmocom/core/select.h>
+#include <osmocom/core/linuxlist.h>
+#include <osmocom/core/hashtable.h>
+#include <osmocom/core/write_queue.h>
+#include <osmocom/core/timer.h>
+#include <osmocom/core/rate_ctr.h>
+#include <osmocom/core/sockaddr_str.h>
+#include <osmocom/gsm/gsm23003.h>
+#include <osmocom/sigtran/osmo_ss7.h>
+#include <osmocom/ctrl/control_if.h>
+#include <osmocom/ranap/RANAP_CN-DomainIndicator.h>
+
+#define DEBUG
+#include <osmocom/core/logging.h>
+
+#include <osmocom/netif/stream.h>
+
+#include <osmocom/mgcp_client/mgcp_client.h>
+#include <osmocom/mgcp_client/mgcp_client_pool.h>
+
+#include <osmocom/hnbgw/umts_cell_id.h>
+#include <osmocom/hnbgw/nft_kpi.h>
+#include <osmocom/hnbgw/cnlink.h>
+#include <osmocom/hnbgw/hnbgw_cn.h>
+
+#define HNB_STORE_RAB_DURATIONS_INTERVAL 1 /* seconds */
+
+#define LOGHNB(HNB_CTX, ss, lvl, fmt, args ...) \
+	LOGP(ss, lvl, "(%s) " fmt, hnb_context_name(HNB_CTX), ## args)
+
+enum hnb_ctrl_node {
+	CTRL_NODE_HNB = _LAST_CTRL_NODE,
+	_LAST_CTRL_NODE_HNB
+};
+
+/* The lifecycle of the hnb_context object is the same as its conn */
+struct hnb_context {
+	/*! Entry in HNB-global list of HNB */
+	struct llist_head list;
+	/*! SCTP socket + write queue for Iuh to this specific HNB */
+	struct osmo_stream_srv *conn;
+	/*! copied from HNB-Identity-Info IE */
+	char identity_info[256];
+	/*! copied from Cell Identity IE */
+	struct umts_cell_id id;
+
+	/*! SCTP stream ID for HNBAP */
+	uint16_t hnbap_stream;
+	/*! SCTP stream ID for RUA */
+	uint16_t rua_stream;
+
+	/*! True if a HNB-REGISTER-REQ from this HNB has been accepted. */
+	bool hnb_registered;
+
+	/* linked list of hnbgw_context_map */
+	struct llist_head map_list;
+
+	/*! pointer to the associated hnb persistent state. Always present after HNB-Register */
+	struct hnb_persistent *persistent;
+};
+
+
+int hnbgw_rua_accept_cb(struct osmo_stream_srv_link *srv, int fd);
+int hnb_ctrl_cmds_install(void);
+int hnb_ctrl_node_lookup(void *data, vector vline, int *node_type, void **node_data, int *i);
+
+struct hnb_context *hnb_context_by_identity_info(const char *identity_info);
+const char *hnb_context_name(struct hnb_context *ctx);
+
+void hnb_context_release(struct hnb_context *ctx);
+void hnb_context_release_ue_state(struct hnb_context *ctx);
+
+unsigned long long hnb_get_updowntime(const struct hnb_context *ctx);
+void hnb_store_rab_durations(struct hnb_context *hnb);

include/osmocom/hnbgw/hnb_persistent.h

@@ -0,0 +1,193 @@
+#pragma once
+
+#include <osmocom/core/select.h>
+#include <osmocom/core/linuxlist.h>
+#include <osmocom/core/hashtable.h>
+#include <osmocom/core/write_queue.h>
+#include <osmocom/core/timer.h>
+#include <osmocom/core/rate_ctr.h>
+#include <osmocom/core/sockaddr_str.h>
+#include <osmocom/gsm/gsm23003.h>
+#include <osmocom/sigtran/osmo_ss7.h>
+#include <osmocom/ctrl/control_if.h>
+#include <osmocom/ranap/RANAP_CN-DomainIndicator.h>
+
+#define DEBUG
+#include <osmocom/core/logging.h>
+
+#include <osmocom/mgcp_client/mgcp_client.h>
+#include <osmocom/mgcp_client/mgcp_client_pool.h>
+
+#include <osmocom/hnbgw/umts_cell_id.h>
+#include <osmocom/hnbgw/nft_kpi.h>
+#include <osmocom/hnbgw/cnlink.h>
+#include <osmocom/hnbgw/hnbgw_cn.h>
+
+#define LOG_HNBP(HNBP, lvl, fmt, args...) \
+	LOGP(DHNB, lvl, "(%s) " fmt, \
+	     (HNBP) ? \
+		     (((HNBP)->id_str && *(HNBP)->id_str) ? (HNBP)->id_str : "no-cell-id") \
+		     : "null", ## args)
+
+
+enum hnb_rate_ctr {
+	HNB_CTR_IUH_ESTABLISHED,
+	HNB_CTR_RANAP_PS_ERR_IND_UL,
+	HNB_CTR_RANAP_CS_ERR_IND_UL,
+	HNB_CTR_RANAP_PS_RESET_REQ_UL,
+	HNB_CTR_RANAP_CS_RESET_REQ_UL,
+
+	HNB_CTR_RANAP_PS_RAB_ACT_REQ,
+	HNB_CTR_RANAP_CS_RAB_ACT_REQ,
+	HNB_CTR_RANAP_PS_RAB_ACT_REQ_UNEXP,
+	HNB_CTR_RANAP_CS_RAB_ACT_REQ_UNEXP,
+
+	HNB_CTR_RANAP_PS_RAB_ACT_CNF,
+	HNB_CTR_RANAP_CS_RAB_ACT_CNF,
+	HNB_CTR_RANAP_PS_RAB_ACT_CNF_UNEXP,
+	HNB_CTR_RANAP_CS_RAB_ACT_CNF_UNEXP,
+
+	HNB_CTR_RANAP_PS_RAB_ACT_FAIL,
+	HNB_CTR_RANAP_CS_RAB_ACT_FAIL,
+	HNB_CTR_RANAP_PS_RAB_ACT_FAIL_UNEXP,
+	HNB_CTR_RANAP_CS_RAB_ACT_FAIL_UNEXP,
+
+	HNB_CTR_RANAP_PS_RAB_MOD_REQ,
+	HNB_CTR_RANAP_CS_RAB_MOD_REQ,
+
+	HNB_CTR_RANAP_PS_RAB_MOD_CNF,
+	HNB_CTR_RANAP_CS_RAB_MOD_CNF,
+
+	HNB_CTR_RANAP_PS_RAB_MOD_FAIL,
+	HNB_CTR_RANAP_CS_RAB_MOD_FAIL,
+
+	HNB_CTR_RANAP_PS_RAB_REL_REQ,
+	HNB_CTR_RANAP_CS_RAB_REL_REQ,
+	HNB_CTR_RANAP_PS_RAB_REL_REQ_ABNORMAL,
+	HNB_CTR_RANAP_CS_RAB_REL_REQ_ABNORMAL,
+	HNB_CTR_RANAP_PS_RAB_REL_REQ_UNEXP,
+	HNB_CTR_RANAP_CS_RAB_REL_REQ_UNEXP,
+
+	HNB_CTR_RANAP_PS_RAB_REL_CNF,
+	HNB_CTR_RANAP_CS_RAB_REL_CNF,
+	HNB_CTR_RANAP_PS_RAB_REL_CNF_UNEXP,
+	HNB_CTR_RANAP_CS_RAB_REL_CNF_UNEXP,
+
+	HNB_CTR_RANAP_PS_RAB_REL_FAIL,
+	HNB_CTR_RANAP_CS_RAB_REL_FAIL,
+	HNB_CTR_RANAP_PS_RAB_REL_FAIL_UNEXP,
+	HNB_CTR_RANAP_CS_RAB_REL_FAIL_UNEXP,
+
+	HNB_CTR_RANAP_PS_RAB_REL_IMPLICIT,
+	HNB_CTR_RANAP_CS_RAB_REL_IMPLICIT,
+	HNB_CTR_RANAP_PS_RAB_REL_IMPLICIT_ABNORMAL,
+	HNB_CTR_RANAP_CS_RAB_REL_IMPLICIT_ABNORMAL,
+
+	HNB_CTR_RUA_ERR_IND,
+
+	HNB_CTR_RUA_PS_CONNECT_UL,
+	HNB_CTR_RUA_CS_CONNECT_UL,
+
+	HNB_CTR_RUA_PS_DISCONNECT_UL,
+	HNB_CTR_RUA_CS_DISCONNECT_UL,
+	HNB_CTR_RUA_PS_DISCONNECT_DL,
+	HNB_CTR_RUA_CS_DISCONNECT_DL,
+
+	HNB_CTR_RUA_PS_DT_UL,
+	HNB_CTR_RUA_CS_DT_UL,
+	HNB_CTR_RUA_PS_DT_DL,
+	HNB_CTR_RUA_CS_DT_DL,
+
+	HNB_CTR_RUA_UDT_UL,
+	HNB_CTR_RUA_UDT_DL,
+
+	HNB_CTR_PS_PAGING_ATTEMPTED,
+	HNB_CTR_CS_PAGING_ATTEMPTED,
+
+	HNB_CTR_RAB_ACTIVE_MILLISECONDS_TOTAL,
+
+	HNB_CTR_DTAP_CS_LU_REQ,
+	HNB_CTR_DTAP_CS_LU_ACC,
+	HNB_CTR_DTAP_CS_LU_REJ,
+
+	HNB_CTR_DTAP_PS_ATT_REQ,
+	HNB_CTR_DTAP_PS_ATT_ACK,
+	HNB_CTR_DTAP_PS_ATT_REJ,
+
+	HNB_CTR_DTAP_PS_RAU_REQ,
+	HNB_CTR_DTAP_PS_RAU_ACK,
+	HNB_CTR_DTAP_PS_RAU_REJ,
+
+	HNB_CTR_GTPU_PACKETS_UL,
+	HNB_CTR_GTPU_TOTAL_BYTES_UL,
+	HNB_CTR_GTPU_UE_BYTES_UL,
+	HNB_CTR_GTPU_PACKETS_DL,
+	HNB_CTR_GTPU_TOTAL_BYTES_DL,
+	HNB_CTR_GTPU_UE_BYTES_DL,
+};
+
+enum hnb_stat {
+	HNB_STAT_UPTIME_SECONDS,
+};
+
+#define HNBP_CTR(hnbp, x) rate_ctr_group_get_ctr((hnbp)->ctrs, x)
+#define HNBP_CTR_INC(hnbp, x) rate_ctr_inc(HNBP_CTR(hnbp, x))
+#define HNBP_CTR_ADD(hnbp, x, y) rate_ctr_add2((hnbp)->ctrs, x, y)
+
+#define HNBP_STAT(hbp, x) osmo_stat_item_group_get_item((hnbp)->statg, x)
+#define HNBP_STAT_SET(hnbp, x, val) osmo_stat_item_set(HNBP_STAT(hnbp, x), val)
+
+/* persistent data for one HNB.  This continues to exist even as conn / hnb_context is deleted on disconnect */
+struct hnb_persistent {
+	/*! Entry in HNBGW-global list of hnb_persistent */
+	struct llist_head list;
+	/*! Entry in hash table g_hnbgw->hnb_persistent_by_id. */
+	struct hlist_node node_by_id;
+	/*! back-pointer to hnb_context.  Can be NULL if no context at this point */
+	struct hnb_context *ctx;
+
+	/*! unique cell identity; copied from HNB REGISTER REQ */
+	struct umts_cell_id id;
+	/*! stringified version of the cell identiy above (for printing/naming) */
+	const char *id_str;
+
+	/*! copied from HNB-Identity-Info IE */
+	time_t updowntime;
+
+	struct rate_ctr_group *ctrs;
+	struct osmo_stat_item_group *statg;
+
+	/* State that the main thread needs in order to know what was requested from the nft worker threads and what
+	 * still needs to be requested. */
+	struct {
+		/* Whether a persistent named counter was added in nftables for this cell id. */
+		bool persistent_counter_added;
+
+		/* The last hNodeB GTP-U address we asked the nft maintenance thread to set up.
+		 * osmo_sockaddr_str_is_nonzero(addr_remote) == false when no rules were added yet, and when
+		 * we asked the nft maintenance thread to remove the rules for this hNodeB because it has
+		 * disconnected. */
+		struct osmo_sockaddr_str addr_remote;
+
+		/* the nft handles needed to clean up the UL and DL rules when the hNodeB disconnects,
+		 * and the last seen counter value gotten from nft. */
+		struct {
+			struct nft_kpi_handle h;
+			struct nft_kpi_val v;
+		} ul;
+		struct {
+			struct nft_kpi_handle h;
+			struct nft_kpi_val v;
+		} dl;
+	} nft_kpi;
+
+	struct osmo_timer_list disconnected_timeout;
+};
+
+struct hnb_persistent *hnb_persistent_alloc(const struct umts_cell_id *id);
+struct hnb_persistent *hnb_persistent_find_by_id(const struct umts_cell_id *id);
+void hnb_persistent_registered(struct hnb_persistent *hnbp);
+void hnb_persistent_deregistered(struct hnb_persistent *hnbp);
+void hnb_persistent_free(struct hnb_persistent *hnbp);
+
+unsigned long long hnbp_get_updowntime(const struct hnb_persistent *hnbp);

include/osmocom/hnbgw/hnbgw.h

@@ -2,29 +2,50 @@
 
 #include <osmocom/core/select.h>
 #include <osmocom/core/linuxlist.h>
+#include <osmocom/core/hashtable.h>
 #include <osmocom/core/write_queue.h>
 #include <osmocom/core/timer.h>
-#include <osmocom/sigtran/sccp_sap.h>
+#include <osmocom/core/rate_ctr.h>
+#include <osmocom/core/sockaddr_str.h>
+#include <osmocom/gsm/gsm23003.h>
 #include <osmocom/sigtran/osmo_ss7.h>
 #include <osmocom/ctrl/control_if.h>
+#include <osmocom/ranap/RANAP_CN-DomainIndicator.h>
+
 #define DEBUG
 #include <osmocom/core/logging.h>
 
+#include <osmocom/mgcp_client/mgcp_client.h>
+#include <osmocom/mgcp_client/mgcp_client_pool.h>
+
+#include <osmocom/hnbgw/nft_kpi.h>
+#include <osmocom/hnbgw/cnlink.h>
+#include <osmocom/hnbgw/hnbgw_cn.h>
+
+#define STORE_UPTIME_INTERVAL	10 /* seconds */
 
 enum {
 	DMAIN,
 	DHNBAP,
 	DRUA,
 	DRANAP,
+	DMGW,
+	DHNB,
+	DCN,
+	DNFT,
 };
 
-#define LOGHNB(x, ss, lvl, fmt, args ...) \
-	LOGP(ss, lvl, "%s " fmt, hnb_context_name(x), ## args)
+extern const struct log_info hnbgw_log_info;
+extern struct vty_app_info hnbgw_vty_info;
 
-enum hnb_ctrl_node {
-	CTRL_NODE_HNB = _LAST_CTRL_NODE,
-	_LAST_CTRL_NODE_HNB
-};
+#define DOMAIN_CS RANAP_CN_DomainIndicator_cs_domain
+#define DOMAIN_PS RANAP_CN_DomainIndicator_ps_domain
+
+extern const struct value_string ranap_domain_names[];
+static inline const char *ranap_domain_name(RANAP_CN_DomainIndicator_t domain)
+{
+	return get_value_string(ranap_domain_names, domain);
+}
 
 #define HNBGW_LOCAL_IP_DEFAULT "0.0.0.0"
 /* TODO: CS and PS now both connect to OsmoSTP, i.e. that's always going to be the same address. Drop the
@@ -32,6 +53,12 @@ enum hnb_ctrl_node {
 #define HNBGW_IUCS_REMOTE_IP_DEFAULT "127.0.0.1"
 #define HNBGW_IUPS_REMOTE_IP_DEFAULT "127.0.0.1"
 
+#define DEFAULT_PC_HNBGW ((23 << 3) + 5)
+#define DEFAULT_PC_MSC ((23 << 3) + 1)
+#define DEFAULT_PC_SGSN ((23 << 3) + 4)
+#define DEFAULT_ADDR_NAME_MSC "addr-dyn-msc-default"
+#define DEFAULT_ADDR_NAME_SGSN "addr-dyn-sgsn-default"
+
 /* 25.467 Section 7.1 */
 #define IUH_DEFAULT_SCTP_PORT	29169
 #define RNA_DEFAULT_SCTP_PORT	25471
@@ -44,82 +71,19 @@ enum hnb_ctrl_node {
 
 #define IUH_MSGB_SIZE	2048
 
-struct umts_cell_id {
-	uint16_t mcc;	/*!< Mobile Country Code */
-	uint16_t mnc;	/*!< Mobile Network Code */
-	uint16_t lac;	/*!< Locaton Area Code */
-	uint16_t rac;	/*!< Routing Area Code */
-	uint16_t sac;	/*!< Service Area Code */
-	uint32_t cid;	/*!< Cell ID */
-};
+struct hnbgw_context_map;
 
-struct hnb_gw;
+static inline bool cnlink_is_cs(const struct hnbgw_cnlink *cnlink)
+{
+	return cnlink && cnlink->pool->domain == DOMAIN_CS;
+}
 
-enum hnbgw_cnlink_state {
-	/* we have just been initialized or were disconnected */
-	CNLINK_S_NULL,
-	/* establishment of the SUA/SCCP link is pending */
-	CNLINK_S_EST_PEND,
-	/* establishment of the SUA/SCCP link was confirmed */
-	CNLINK_S_EST_CONF,
-	/* we have esnt the RANAP RESET and wait for the ACK */
-	CNLINK_S_EST_RST_TX_WAIT_ACK,
-	/* we have received the RANAP RESET ACK and are active */
-	CNLINK_S_EST_ACTIVE,
-};
+static inline bool cnlink_is_ps(const struct hnbgw_cnlink *cnlink)
+{
+	return cnlink && cnlink->pool->domain == DOMAIN_PS;
+}
 
-struct hnbgw_cnlink {
-	struct llist_head list;
-	enum hnbgw_cnlink_state state;
-	struct hnb_gw *gw;
-	/* timer for re-transmitting the RANAP Reset */
-	struct osmo_timer_list T_RafC;
-	/* reference to the SCCP User SAP by which we communicate */
-	struct osmo_sccp_instance *sccp;
-	struct osmo_sccp_user *sccp_user;
-	uint32_t next_conn_id;
-
-	/* linked list of hnbgw_context_map */
-	struct llist_head map_list;
-};
-
-struct hnb_context {
-	/*! Entry in HNB-global list of HNB */
-	struct llist_head list;
-	/*! HNB-GW we are part of */
-	struct hnb_gw *gw;
-	/*! SCTP socket + write queue for Iuh to this specific HNB */
-	struct osmo_stream_srv *conn;
-	/*! copied from HNB-Identity-Info IE */
-	char identity_info[256];
-	/*! copied from Cell Identity IE */
-	struct umts_cell_id id;
-
-	/*! SCTP stream ID for HNBAP */
-	uint16_t hnbap_stream;
-	/*! SCTP stream ID for RUA */
-	uint16_t rua_stream;
-
-	/*! True if a HNB-REGISTER-REQ from this HNB has been accepted. Note that
-	 * this entire data structure is freed if the HNB sends HNB-DE-REGISTER-REQ. */
-	bool hnb_registered;
-
-	/* linked list of hnbgw_context_map */
-	struct llist_head map_list;
-};
-
-struct ue_context {
-	/*! Entry in the HNB-global list of UE */
-	struct llist_head list;
-	/*! Unique Context ID for this UE */
-	uint32_t context_id;
-	char imsi[16+1];
-	uint32_t tmsi;
-	/*! UE is serviced via this HNB */
-	struct hnb_context *hnb;
-};
-
-struct hnb_gw {
+struct hnbgw {
 	struct {
 		const char *iuh_local_ip;
 		/*! SCTP port for Iuh listening */
@@ -127,48 +91,97 @@ struct hnb_gw {
 		/*! The UDP port where we receive multiplexed CS user
 		 * plane traffic from HNBs */
 		uint16_t iuh_cs_mux_port;
-		const char *iucs_remote_addr_name;
-		const char *iups_remote_addr_name;
+		struct osmo_plmn_id plmn;
 		uint16_t rnc_id;
 		bool hnbap_allow_tmsi;
 		/*! print hnb-id (true) or MCC-MNC-LAC-RAC-SAC (false) in logs */
 		bool log_prefix_hnb_id;
+		bool accept_all_hnb;
+		struct mgcp_client_conf *mgcp_client;
+		struct {
+			char *local_addr;
+			uint16_t local_port;
+			char *remote_addr;
+			uint16_t remote_port;
+			struct {
+				char *access;
+				char *core;
+			} netinst;
+		} pfcp;
+		struct {
+			bool enable;
+			/* The table name as used in nftables for the ruleset owned by this process. It is "osmo-hnbgw"
+			 * by default. */
+			char *table_name;
+		} nft_kpi;
 	} config;
 	/*! SCTP listen socket for incoming connections */
 	struct osmo_stream_srv_link *iuh;
 	/* list of struct hnb_context */
 	struct llist_head hnb_list;
-	/* list of struct ue_context */
-	struct llist_head ue_list;
+
+	/* list of struct hnb_persistent */
+	struct llist_head hnb_persistent_list;
+	/* optimized lookup for hnb_persistent, by cell id string */
+	DECLARE_HASHTABLE(hnb_persistent_by_id, 5);
+
+	struct osmo_timer_list store_uptime_timer;
 	/* next availble UE Context ID */
 	uint32_t next_ue_ctx_id;
 	struct ctrl_handle *ctrl;
 	/* currently active CN links for CS and PS */
 	struct {
-		struct osmo_sccp_instance *client;
-		struct hnbgw_cnlink *cnlink;
-		struct osmo_sccp_addr local_addr;
-		struct osmo_sccp_addr iucs_remote_addr;
-		struct osmo_sccp_addr iups_remote_addr;
+		/* List of hnbgw_sccp_user */
+		struct llist_head users;
+
+		/* Pool of core network peers: MSCs for IuCS */
+		struct hnbgw_cnpool *cnpool_iucs;
+		/* Pool of core network peers: SGSNs for IuPS */
+		struct hnbgw_cnpool *cnpool_iups;
 	} sccp;
+	/* MGW pool, also includes the single MGCP client as fallback if no
+	 * pool is configured. */
+	struct mgcp_client_pool *mgw_pool;
+
+	struct {
+		struct osmo_pfcp_endpoint *ep;
+		struct osmo_pfcp_cp_peer *cp_peer;
+		/* Running counters for the PFCP conn */
+		struct osmo_stat_item_group *statg;
+	} pfcp;
+
+	struct osmo_timer_list hnb_store_rab_durations_timer;
+
+	struct {
+		bool active;
+		struct osmo_timer_list get_counters_timer;
+		struct timespec next_timer;
+	} nft_kpi;
 };
 
+extern struct hnbgw *g_hnbgw;
 extern void *talloc_asn1_ctx;
 
-struct hnb_context *hnb_context_by_id(struct hnb_gw *gw, uint32_t cid);
-struct hnb_context *hnb_context_by_identity_info(struct hnb_gw *gw, const char *identity_info);
-const char *hnb_context_name(struct hnb_context *ctx);
-unsigned hnb_contexts(const struct hnb_gw *gw);
+void g_hnbgw_alloc(void *ctx);
 
-struct ue_context *ue_context_by_id(struct hnb_gw *gw, uint32_t id);
-struct ue_context *ue_context_by_imsi(struct hnb_gw *gw, const char *imsi);
-struct ue_context *ue_context_by_tmsi(struct hnb_gw *gw, uint32_t tmsi);
-struct ue_context *ue_context_alloc(struct hnb_context *hnb, const char *imsi,
-				    uint32_t tmsi);
-void ue_context_free(struct ue_context *ue);
+int hnbgw_rua_accept_cb(struct osmo_stream_srv_link *srv, int fd);
+int hnbgw_mgw_setup(void);
 
-struct hnb_context *hnb_context_alloc(struct hnb_gw *gw, struct osmo_stream_srv_link *link, int new_fd);
-void hnb_context_release(struct hnb_context *ctx);
-
-void hnbgw_vty_init(struct hnb_gw *gw, void *tall_ctx);
+void hnbgw_vty_init(void);
 int hnbgw_vty_go_parent(struct vty *vty);
+
+/* Return true when the user configured GTP mapping to be enabled, by configuring a PFCP link to a UPF.
+ * Return false when the user configured to skip GTP mapping and RANAP PS RAB Requests/Responses should be passed thru
+ * 1:1.
+ * GTP mapping means that there are two GTP tunnels, one towards HNB and one towards CN, and we forward payloads between
+ * the two tunnels, mapping the TEIDs and GTP addresses. */
+static inline bool hnb_gw_is_gtp_mapping_enabled(void)
+{
+	return g_hnbgw->config.pfcp.remote_addr != NULL;
+}
+
+struct msgb *hnbgw_ranap_msg_alloc(const char *name);
+
+int hnbgw_peek_l3_ul(struct hnbgw_context_map *map, struct msgb *ranap_msg);
+
+uint32_t get_next_ue_ctx_id(void);

include/osmocom/hnbgw/hnbgw_cn.h

@@ -1,5 +1,64 @@
 #pragma once
 
-#include <osmocom/hnbgw/hnbgw.h>
+#include <stdint.h>
+#include <osmocom/core/rate_ctr.h>
 
-int hnbgw_cnlink_init(struct hnb_gw *gw, const char *stp_host, uint16_t stp_port, const char *local_ip);
+#include <osmocom/sigtran/sccp_sap.h>
+
+#include <osmocom/ranap/RANAP_CN-DomainIndicator.h>
+
+struct hnbgw_context_map;
+
+enum hnbgw_cnpool_ctr {
+	/* TODO: basic counters completely missing
+	 * ...
+	 */
+
+	/* Counters related to link selection from a CN pool. */
+	CNPOOL_CTR_SUBSCR_NO_CNLINK,
+	CNPOOL_CTR_EMERG_FORWARDED,
+	CNPOOL_CTR_EMERG_LOST,
+};
+#define CNPOOL_CTR_INC(cnpool, x) rate_ctr_inc2((cnpool)->ctrs, x)
+
+/* User provided configuration for struct hnbgw_cnpool. */
+struct hnbgw_cnpool_cfg {
+	uint8_t nri_bitlen;
+	struct osmo_nri_ranges *null_nri_ranges;
+};
+
+/* Collection of CN peers to distribute UE connections across. MSCs for DOMAIN_CS, SGSNs for DOMAIN_PS. */
+struct hnbgw_cnpool {
+	RANAP_CN_DomainIndicator_t domain;
+
+	/* CN pool string used in VTY config and logging, "iucs" or "iups". */
+	const char *pool_name;
+	/* CN peer string used in VTY config and logging, "msc" or "sgsn". */
+	const char *peer_name;
+	/* What we use as the remote MSC/SGSN point-code if the user does not configure any address. */
+	uint32_t default_remote_pc;
+	const char *default_addr_name;
+
+	struct hnbgw_cnpool_cfg vty;
+	struct hnbgw_cnpool_cfg use;
+
+	/* List of struct hnbgw_cnlink */
+	struct llist_head cnlinks;
+
+	unsigned int round_robin_next_nr;
+	/* Emergency calls potentially select a different set of MSCs, so to not mess up the normal round-robin
+	 * behavior, emergency calls need a separate round-robin counter. */
+	unsigned int round_robin_next_emerg_nr;
+
+	/* Running counters for this pool */
+	struct rate_ctr_group *ctrs;
+};
+
+struct hnbgw_cnpool *hnbgw_cnpool_alloc(RANAP_CN_DomainIndicator_t domain);
+
+struct hnbgw_cnlink *hnbgw_cnlink_select(struct hnbgw_context_map *map);
+
+void hnbgw_cnpool_start(struct hnbgw_cnpool *cnpool);
+void hnbgw_cnpool_cnlinks_start_or_restart(struct hnbgw_cnpool *cnpool);
+struct hnbgw_cnlink *cnlink_get_nr(struct hnbgw_cnpool *cnpool, int nr, bool create_if_missing);
+void hnbgw_cnpool_apply_cfg(struct hnbgw_cnpool *cnpool);

include/osmocom/hnbgw/hnbgw_hnbap.h

@@ -1,6 +1,9 @@
+/* HNBAP, 3GPP TS 25.469 */
 #pragma once
 
 #include <osmocom/hnbgw/hnbgw.h>
 
+struct hnb_context;
+
 int hnbgw_hnbap_rx(struct hnb_context *hnb, struct msgb *msg);
 int hnbgw_hnbap_init(void);

include/osmocom/hnbgw/hnbgw_pfcp.h

@@ -0,0 +1,9 @@
+#pragma once
+
+enum hnbgw_upf_stats {
+	HNBGW_UPF_STAT_ASSOCIATED,
+};
+#define HNBGW_UPF_STAT_SET(stat, val) osmo_stat_item_set(osmo_stat_item_group_get_item(g_hnbgw->pfcp.statg, (stat)), (val))
+
+int hnbgw_pfcp_init(void);
+void hnbgw_pfcp_release(void);

include/osmocom/hnbgw/hnbgw_ranap.h

@@ -1,6 +1,18 @@
+/* RANAP, 3GPP TS 25.413 */
 #pragma once
 
+#include <osmocom/ranap/ranap_ies_defs.h>
 #include <osmocom/hnbgw/hnbgw.h>
 
-int hnbgw_ranap_rx(struct msgb *msg, uint8_t *data, size_t len);
+struct osmo_scu_unitdata_param;
+
+ranap_message *hnbgw_decode_ranap_cn_co(struct msgb *ranap_msg);
+
+int hnbgw_ranap_rx_udt_ul(struct msgb *msg, uint8_t *data, size_t len);
+int hnbgw_ranap_rx_data_ul(struct hnbgw_context_map *map, struct msgb *ranap_msg);
+
+int hnbgw_ranap_rx_udt_dl(struct hnbgw_cnlink *cnlink, const struct osmo_scu_unitdata_param *unitdata,
+			  const uint8_t *data, unsigned int len);
+int hnbgw_ranap_rx_data_dl(struct hnbgw_context_map *map, struct msgb *ranap_msg);
 int hnbgw_ranap_init(void);
+

include/osmocom/hnbgw/hnbgw_rua.h

@@ -1,13 +1,16 @@
+/* RUA, 3GPP TS 25.468 */
 #pragma once
 
 #include <osmocom/hnbgw/hnbgw.h>
 #include <osmocom/rua/RUA_Cause.h>
 
+struct hnb_context;
+
 int hnbgw_rua_rx(struct hnb_context *hnb, struct msgb *msg);
-int hnbgw_rua_init(void);
 
 int rua_tx_udt(struct hnb_context *hnb, const uint8_t *data, unsigned int len);
 int rua_tx_dt(struct hnb_context *hnb, int is_ps, uint32_t context_id,
 	      const uint8_t *data, unsigned int len);
 int rua_tx_disc(struct hnb_context *hnb, int is_ps, uint32_t context_id,
 	        const RUA_Cause_t *cause, const uint8_t *data, unsigned int len);
+

include/osmocom/hnbgw/hnbgw_sccp.h

@@ -0,0 +1,66 @@
+/* SCCP, ITU Q.711 - Q.714 */
+#pragma once
+
+#include <stdint.h>
+
+#include <osmocom/core/hashtable.h>
+#include <osmocom/core/linuxlist.h>
+#include <osmocom/core/prim.h>
+#include <osmocom/core/msgb.h>
+#include <osmocom/core/use_count.h>
+
+#include <osmocom/sigtran/sccp_sap.h>
+
+struct hnbgw_cnlink;
+
+/* osmo-hnbgw keeps a single hnbgw_sccp_user per osmo_sccp_instance, for the local point-code and SSN == RANAP.
+ * This relates the (opaque) osmo_sccp_user to osmo-hnbgw's per-ss7 state. */
+struct hnbgw_sccp_user {
+	/* entry in g_hnbgw->sccp.users */
+	struct llist_head entry;
+
+	/* logging context */
+	char *name;
+
+	/* Which 'cs7 instance' is this for? Below sccp_user is registered at the osmo_sccp_instance ss7->sccp. */
+	struct osmo_ss7_instance *ss7;
+
+	/* Local address: cs7 instance's primary PC if present, else the default HNBGW PC; with SSN == RANAP. */
+	struct osmo_sccp_addr local_addr;
+
+	/* osmo_sccp API state for above local address on above ss7 instance. */
+	struct osmo_sccp_user *sccp_user;
+
+	/* Ref count of users of this struct, ie.referencing it in cnlink->hnbgw_sccp_user */
+	struct osmo_use_count use_count;
+
+	/* Fast access to the hnbgw_context_map responsible for a given SCCP conn_id of the ss7->sccp instance.
+	 * hlist_node: hnbgw_context_map->hnbgw_sccp_user_entry. */
+	DECLARE_HASHTABLE(hnbgw_context_map_by_conn_id, 6);
+};
+
+#define LOG_HSU(HSU, SUBSYS, LEVEL, FMT, ARGS...) \
+	LOGP(SUBSYS, LEVEL, "(%s) " FMT, (HSU) ? (HSU)->name : "null", ##ARGS)
+
+#define HSU_USE_CNLINK "cnlink"
+#define hnbgw_sccp_user_get(hsu, use) \
+	OSMO_ASSERT(osmo_use_count_get_put(&(hsu)->use_count, use, 1) == 0)
+#define hnbgw_sccp_user_put(hsu, use) \
+	OSMO_ASSERT(osmo_use_count_get_put(&(hsu)->use_count, use, -1) == 0)
+
+struct hnbgw_sccp_user *hnbgw_sccp_user_alloc(int ss7_inst_id);
+
+int hnbgw_sccp_user_tx_unitdata_req(struct hnbgw_sccp_user *hsu, const struct osmo_sccp_addr *called_addr,
+				    struct msgb *ranap_msg);
+int hnbgw_sccp_user_tx_connect_req(struct hnbgw_sccp_user *hsu, const struct osmo_sccp_addr *called_addr,
+				   uint32_t scu_conn_id, struct msgb *ranap_msg);
+int hnbgw_sccp_user_tx_data_req(struct hnbgw_sccp_user *hsu, uint32_t scu_conn_id,
+				struct msgb *ranap_msg);
+int hnbgw_sccp_user_tx_disconnect_req(struct hnbgw_sccp_user *hsu, uint32_t scu_conn_id);
+
+static inline struct osmo_sccp_instance *hnbgw_sccp_user_get_sccp_instance(const struct hnbgw_sccp_user *hsu)
+{
+	if (!hsu->ss7)
+		return NULL;
+	return osmo_ss7_get_sccp(hsu->ss7);
+}

include/osmocom/hnbgw/kpi.h

@@ -0,0 +1,11 @@
+#pragma once
+
+#include <osmocom/ranap/ranap_ies_defs.h>
+
+#include <osmocom/hnbgw/hnbgw.h>
+
+void kpi_ranap_process_ul(struct hnbgw_context_map *map, ranap_message *ranap);
+void kpi_ranap_process_dl(struct hnbgw_context_map *map, ranap_message *ranap);
+
+void kpi_dtap_process_ul(struct hnbgw_context_map *map, const uint8_t *buf, unsigned int len, uint8_t sapi);
+void kpi_dtap_process_dl(struct hnbgw_context_map *map, const uint8_t *buf, unsigned int len, uint8_t sapi);

include/osmocom/hnbgw/mgw_fsm.h

@@ -0,0 +1,9 @@
+#pragma once
+
+#include <osmocom/ranap/ranap_ies_defs.h>
+
+int handle_cs_rab_ass_req(struct hnbgw_context_map *map, struct msgb *ranap_msg, ranap_message *message);
+int mgw_fsm_handle_cs_rab_ass_resp(struct hnbgw_context_map *map, struct msgb *ranap_msg, ranap_message *message);
+int mgw_fsm_release(struct hnbgw_context_map *map);
+
+uint64_t mgw_fsm_get_elapsed_ms(struct hnbgw_context_map *map, const struct timespec *now);

include/osmocom/hnbgw/nft_kpi.h

@@ -0,0 +1,25 @@
+#pragma once
+#include <stdint.h>
+#include <stdbool.h>
+
+struct hnb_persistent;
+
+/* A "handle" that nftables returns for chains and rules -- a plain number. Deleting an unnamed rule can only be done by
+ * such a handle. */
+struct nft_kpi_handle {
+	bool handle_present;
+	int64_t handle;
+};
+
+/* One GTP-U packet and byte counter cache, i.e. for one UL/DL direction of one hNodeB. */
+struct nft_kpi_val {
+	uint64_t packets;
+	uint64_t total_bytes;
+	uint64_t ue_bytes;
+};
+
+void nft_kpi_init(const char *table_name);
+void nft_kpi_hnb_persistent_add(struct hnb_persistent *hnbp);
+void nft_kpi_hnb_persistent_remove(struct hnb_persistent *hnbp);
+int nft_kpi_hnb_start(struct hnb_persistent *hnbp, const struct osmo_sockaddr_str *gtpu_remote);
+void nft_kpi_hnb_stop(struct hnb_persistent *hnbp);

include/osmocom/hnbgw/ps_rab_ass_fsm.h

@@ -0,0 +1,15 @@
+#pragma once
+
+#include <osmocom/ranap/ranap_ies_defs.h>
+
+enum ps_rab_ass_fsm_event {
+	PS_RAB_ASS_EV_LOCAL_F_TEIDS_RX,
+	PS_RAB_ASS_EV_RAB_ASS_RESP,
+	PS_RAB_ASS_EV_RAB_ESTABLISHED,
+	PS_RAB_ASS_EV_RAB_RELEASED,
+	PS_RAB_ASS_EV_RAB_FAIL,
+};
+
+int hnbgw_gtpmap_rx_rab_ass_req(struct hnbgw_context_map *map, struct msgb *ranap_msg, ranap_message *message);
+int hnbgw_gtpmap_rx_rab_ass_resp(struct hnbgw_context_map *map, struct msgb *ranap_msg, ranap_message *message);
+void hnbgw_gtpmap_release(struct hnbgw_context_map *map);

include/osmocom/hnbgw/ps_rab_fsm.h

@@ -0,0 +1,99 @@
+#pragma once
+
+#include <osmocom/core/linuxlist.h>
+#include <osmocom/core/socket.h>
+#include <osmocom/core/use_count.h>
+#include <osmocom/pfcp/pfcp_msg.h>
+
+/* A GTP tunnel has two endpoints, each endpoint has an IP address and a Tunnel Endpoint ID. So two struct addr_teid
+ * identify one GTP tunnel. For GTP mapping between HNB and CN, we have two tunnels, see also struct half_gtp_map. The
+ * combination of IP address and TEID is also known as F-TEID (fully qualified TEID). */
+struct addr_teid {
+	bool present;
+	struct osmo_sockaddr addr;
+	uint32_t teid;
+};
+
+/* One half_gtp_map represents one GTP tunnel, either on the HNB side or on the CN side. Two struct half_gtp_map make up
+ * a GTP mapping between HNB and CN. One half_gtp_map for the Access (HNB) side, one for the Core (CN) side. The PFCP
+ * PDR (Packet Detection Rule) identifies packets coming in on the GTP tunnel the half_gtp_map represents, while the
+ * PFCP FAR (Forwarding Action Rule) identifies the GTP destination, i.e. the other side's GTP tunnel. So a
+ * half_gtp_map.far_id is closely tied to the other half_gtp_map, and makes little sense on its own.
+ *
+ * half_gtp_map     |    half_gtp_map
+ * Access        HNBGW+UPF       Core
+ * remote     local | local    remote
+ *     -->PDR-FAR-->|
+ *                  |<--FAR-PDR<--
+ *
+ * See ps_rab.core, ps_rab.access.
+ */
+struct half_gtp_map {
+	/* GTP endpoint, obtained from incoming RAB Assignment Request/Response.
+	 * This is the remote side as seen from the UPF's point of view.
+	 * For example, ps_rab.core.remote is the CN GTP that the RAB Assignment Request told us.
+	 * ps_rab.access.remote is the HNB GTP that RAB Assignment Response told us. */
+	struct addr_teid remote;
+	/* UPF GTP endpoint, obtained from PFCP Session Establishment Response. */
+	struct addr_teid local;
+	/* PFCP Packet Detection Rule id that detects GTP-U packets coming from Core/Access */
+	uint16_t pdr_id;
+	/* PFCP Forward Action Rule id that forwards GTP-U packets to Access/Core */
+	uint32_t far_id;
+	/* Whether the RANAP message this RAB's remote address was obtained from had the address encoded in x213_nsap */
+	bool use_x213_nsap;
+};
+
+/* A PS RAB's PFCP state. For the related RANAP state, see struct ps_rab_ass instead. */
+struct ps_rab {
+	/* Instance of ps_rab_fsm. */
+	struct osmo_fsm_inst *fi;
+
+	/* List entry and backpointer.
+	 * If map == NULL, do not call llist_del(&entry): the hnbgw_context_map may deallocate before the PFCP release
+	 * is complete, in which case it sets map = NULL. */
+	struct llist_head entry;
+	struct hnbgw_context_map *map;
+
+	/* RAB-ID used in RANAP RAB AssignmentRequest and Response messages */
+	uint8_t rab_id;
+	/* Backpointer to the ps_rab_ass_fsm for the RAB Assignment Request from Core that created this RAB.
+	 * There are two separate RAB Assignment FSMs responsible for this RAB, one for the Request message and one for
+	 * the Response message. Each RAB Assignment FSM may be responsible for N other RABs besides this one. */
+	struct osmo_fsm_inst *req_fi;
+	/* Backpointer to the ps_rab_ass_fsm for the RAB Assignment Response from Access that confirmed this RAB. */
+	struct osmo_fsm_inst *resp_fi;
+
+	/* PFCP session controlling the GTP mapping for this RAB */
+	uint64_t cp_seid;
+	struct osmo_pfcp_ie_f_seid up_f_seid;
+	bool release_requested;
+
+	/* 'local' and 'remote' refer to the GTP information from the UPF's point of view:
+	 * HNB                             UPF                 CN
+	 * access.remote <---> access.local | core.local <---> core.remote
+	 */
+	struct half_gtp_map core;
+	struct half_gtp_map access;
+
+	struct osmo_use_count use_count;
+};
+
+struct ps_rab *ps_rab_start(struct hnbgw_context_map *map, uint8_t rab_id,
+			    const struct addr_teid *core_f_teid, bool use_x213_nsap,
+			    struct osmo_fsm_inst *req_fi);
+
+struct ps_rab *ps_rab_get(struct hnbgw_context_map *map, uint8_t rab_id);
+bool ps_rab_is_established(const struct ps_rab *rab);
+void ps_rab_release(struct ps_rab *rab, struct osmo_fsm_inst *notify_fi);
+
+struct ps_rab_rx_args {
+	struct addr_teid f_teid;
+	bool use_x213_nsap;
+	struct osmo_fsm_inst *notify_fi;
+};
+int ps_rab_rx_access_remote_f_teid(struct hnbgw_context_map *map, uint8_t rab_id,
+				   const struct ps_rab_rx_args *args);
+
+struct ps_rab *ps_rab_find_by_seid(uint64_t seid, bool is_cp_seid);
+void ps_rab_pfcp_set_msg_ctx(struct ps_rab *rab, struct osmo_pfcp_msg *m);

include/osmocom/hnbgw/ranap_rab_ass.h

@@ -0,0 +1,20 @@
+#pragma once
+
+struct msgb *ranap_rab_ass_req_encode(RANAP_RAB_AssignmentRequestIEs_t *rab_assignment_request_ies);
+int ranap_rab_ass_resp_encode(uint8_t *data, unsigned int len,
+			      RANAP_RAB_AssignmentResponseIEs_t *rab_assignment_response_ies);
+
+int ranap_rab_ass_req_ies_extract_inet_addr(struct osmo_sockaddr *addr, uint8_t *rab_id,
+					    RANAP_RAB_AssignmentRequestIEs_t *ies, unsigned int index);
+int ranap_rab_ass_resp_ies_extract_inet_addr(struct osmo_sockaddr *addr, RANAP_RAB_AssignmentResponseIEs_t *ies,
+					     uint8_t rab_id);
+
+int ranap_rab_ass_req_ies_replace_inet_addr(RANAP_RAB_AssignmentRequestIEs_t *ies, struct osmo_sockaddr *addr,
+					    uint8_t rab_id);
+int ranap_rab_ass_resp_ies_replace_inet_addr(RANAP_RAB_AssignmentResponseIEs_t *ies, struct osmo_sockaddr *addr,
+					     uint8_t rab_id);
+
+bool ranap_rab_ass_req_ies_check_release(RANAP_RAB_AssignmentRequestIEs_t *ies, uint8_t rab_id);
+bool ranap_rab_ass_resp_ies_check_failure(RANAP_RAB_AssignmentResponseIEs_t *ies, uint8_t rab_id);
+
+int ranap_rab_ass_req_ies_get_count(RANAP_RAB_AssignmentRequestIEs_t *ies);

include/osmocom/hnbgw/tdefs.h

@@ -0,0 +1,7 @@
+#pragma once
+
+#include <osmocom/core/tdef.h>
+
+extern struct osmo_tdef mgw_fsm_T_defs[];
+extern struct osmo_tdef hnbgw_T_defs[];
+extern struct osmo_tdef_group hnbgw_tdef_group[];

include/osmocom/hnbgw/umts_cell_id.h

@@ -0,0 +1,34 @@
+#pragma once
+
+#include <stdint.h>
+#include <unistd.h>
+#include <osmocom/gsm/gsm23003.h>
+
+struct umts_cell_id {
+	struct osmo_plmn_id plmn;	/*!< Mobile Country Code and Mobile Network Code (000-00 to 999-999) */
+	uint16_t lac;	/*!< Locaton Area Code (1-65534) */
+	uint8_t rac;	/*!< Routing Area Code (0-255) */
+	uint16_t sac;	/*!< Service Area Code */
+	uint32_t cid;	/*!< Cell ID */
+};
+int umts_cell_id_to_str_buf(char *buf, size_t buflen, const struct umts_cell_id *ucid);
+char *umts_cell_id_to_str_c(void *ctx, const struct umts_cell_id *ucid);
+const char *umts_cell_id_to_str(const struct umts_cell_id *ucid);
+int umts_cell_id_from_str(struct umts_cell_id *ucid, const char *instr);
+uint32_t umts_cell_id_hash(const struct umts_cell_id *ucid);
+
+/*! are both given umts_cell_id euqal? */
+static inline bool umts_cell_id_equal(const struct umts_cell_id *a, const struct umts_cell_id *b)
+{
+	if (osmo_plmn_cmp(&a->plmn, &b->plmn))
+		return false;
+	if (a->lac != b->lac)
+		return false;
+	if (a->rac != b->rac)
+		return false;
+	if (a->sac != b->sac)
+		return false;
+	if (a->cid != b->cid)
+		return false;
+	return true;
+}

include/osmocom/hnbgw/vty.h

@@ -4,8 +4,14 @@
 
 enum osmo_iuh_vty_node {
 	HNBGW_NODE = _LAST_OSMOVTY_NODE + 1,
+	HNB_NODE,
 	IUH_NODE,
 	IUCS_NODE,
 	IUPS_NODE,
+	MGCP_NODE,
+	MGW_NODE,
+	PFCP_NODE,
+	MSC_NODE,
+	SGSN_NODE,
 };
 

osmoappdesc.py

@@ -1,6 +1,6 @@
 #!/usr/bin/env python3
 
-# (C) 2021 by sysmocom - s.m.f.c. GmbH <info@sysmocom.de>
+# (C) 2021 by sysmocom - s.f.m.c. GmbH <info@sysmocom.de>
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
 # the Free Software Foundation, either version 3 of the License, or

src/osmo-hnbgw/Makefile.am

@@ -19,27 +19,45 @@ AM_CFLAGS = \
 	$(LIBOSMORUA_CFLAGS) \
 	$(LIBOSMORANAP_CFLAGS) \
 	$(LIBOSMOHNBAP_CFLAGS) \
+	$(LIBOSMOMGCPCLIENT_CFLAGS) \
+	$(LIBNFTABLES_CFLAGS) \
 	$(NULL)
 
 AM_LDFLAGS = \
 	$(COVERAGE_LDFLAGS) \
 	$(NULL)
 
-bin_PROGRAMS = \
-	osmo-hnbgw \
+noinst_LTLIBRARIES = \
+	libhnbgw.la \
 	$(NULL)
 
-osmo_hnbgw_SOURCES = \
+libhnbgw_la_SOURCES = \
+	hnb.c \
+	hnb_persistent.c \
 	hnbgw.c \
 	hnbgw_hnbap.c \
+	hnbgw_l3.c \
 	hnbgw_rua.c \
 	hnbgw_ranap.c \
+	hnbgw_sccp.c \
 	hnbgw_vty.c \
 	context_map.c \
+	context_map_rua.c \
+	context_map_sccp.c \
 	hnbgw_cn.c \
+	cnlink.c \
+	cnlink_fsm.c \
+	cnlink_paging.c \
+	ranap_rab_ass.c \
+	mgw_fsm.c \
+	kpi_dtap.c \
+	kpi_ranap.c \
+	tdefs.c \
+	umts_cell_id.c \
+	nft_kpi.c \
 	$(NULL)
 
-osmo_hnbgw_LDADD = \
+libhnbgw_la_LIBADD = \
 	$(LIBASN1C_LIBS) \
 	$(LIBOSMOCORE_LIBS) \
 	$(LIBOSMOGSM_LIBS) \
@@ -52,4 +70,32 @@ osmo_hnbgw_LDADD = \
 	$(LIBOSMORANAP_LIBS) \
 	$(LIBOSMOHNBAP_LIBS) \
 	$(LIBSCTP_LIBS) \
+	$(LIBOSMOMGCPCLIENT_LIBS) \
+	$(LIBNFTABLES_LIBS) \
+	$(NULL)
+
+if ENABLE_PFCP
+AM_CFLAGS += \
+	$(LIBOSMOPFCP_CFLAGS) \
+	$(NULL)
+libhnbgw_la_LIBADD += \
+	$(LIBOSMOPFCP_LIBS) \
+	$(NULL)
+libhnbgw_la_SOURCES += \
+	hnbgw_pfcp.c \
+	ps_rab_ass_fsm.c \
+	ps_rab_fsm.c \
+	$(NULL)
+endif
+
+bin_PROGRAMS = \
+	osmo-hnbgw \
+	$(NULL)
+
+osmo_hnbgw_SOURCES = \
+	osmo_hnbgw_main.c \
+	$(NULL)
+
+osmo_hnbgw_LDADD = \
+	libhnbgw.la \
 	$(NULL)

src/osmo-hnbgw/cnlink.c

@@ -0,0 +1,554 @@
+/* (C) 2023 by sysmocom s.f.m.c. GmbH <info@sysmocom.de>
+ * All Rights Reserved
+ *
+ * Author: Neels Hofmeyr
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include <osmocom/core/fsm.h>
+#include <osmocom/core/tdef.h>
+#include <osmocom/core/stats.h>
+#include <osmocom/core/stat_item.h>
+
+#include <osmocom/gsm/gsm23236.h>
+
+#include <osmocom/sigtran/sccp_helpers.h>
+
+#include <asn1c/asn1helpers.h>
+#include <osmocom/ranap/ranap_ies_defs.h>
+#include <osmocom/ranap/ranap_msg_factory.h>
+
+#include <osmocom/hnbgw/hnbgw.h>
+#include <osmocom/hnbgw/hnbgw_cn.h>
+#include <osmocom/hnbgw/tdefs.h>
+#include <osmocom/hnbgw/context_map.h>
+
+static const struct rate_ctr_desc cnlink_ctr_description[] = {
+	[CNLINK_CTR_RANAP_RX_UDT_RESET] = {
+		"ranap:rx:udt:reset",
+		"RANAP Unitdata RESET messages received"
+	},
+	[CNLINK_CTR_RANAP_RX_UDT_RESET_ACK] = {
+		"ranap:rx:udt:reset_ack",
+		"RANAP Unitdata RESET ACK messages received",
+	},
+	[CNLINK_CTR_RANAP_RX_UDT_PAGING] = {
+		"ranap:rx:udt:paging",
+		"RANAP Unitdata PAGING messages received",
+	},
+	[CNLINK_CTR_RANAP_RX_UDT_UNKNOWN] = {
+		"ranap:rx:udt:unknown",
+		"Unknown RANAP Unitdata messages received",
+	},
+	[CNLINK_CTR_RANAP_RX_UDT_UNSUPPORTED] = {
+		"ranap:rx:udt:unsupported",
+		"Unsupported RANAP Unitdata messages received",
+	},
+	[CNLINK_CTR_RANAP_RX_UDT_OVERLOAD_IND] = {
+		"ranap:rx:udt:overload_ind",
+		"RANAP Unitdata Overload Indications received",
+	},
+	[CNLINK_CTR_RANAP_RX_UDT_ERROR_IND] = {
+		"ranap:rx:udt:error_ind",
+		"RANAP Unitdata Error Indications received",
+	},
+
+	[CNLINK_CTR_RANAP_TX_UDT_RESET] = {
+		"ranap:tx:udt:reset",
+		"RANAP Unitdata RESET messages transmitted",
+	},
+	[CNLINK_CTR_RANAP_TX_UDT_RESET_ACK] = {
+		"ranap:tx:udt:reset_ack",
+		"RANAP Unitdata RESET ACK messages transmitted",
+	},
+
+	/* SCCP Counters: */
+	[CNLINK_CTR_SCCP_N_UNITDATA_REQ] = {
+		"sccp:n_unit_data:req",
+		"Submit SCCP N-UNITDATA.req (UL)"
+	},
+	[CNLINK_CTR_SCCP_N_UNITDATA_IND] = {
+		"sccp:n_unit_data:ind",
+		"Received SCCP N-UNITDATA.ind (DL)"
+	},
+	[CNLINK_CTR_SCCP_N_NOTICE_IND] = {
+		"sccp:n_notice:ind",
+		"Received SCCP N-NOTICE.ind"
+	},
+	[CNLINK_CTR_SCCP_N_CONNECT_REQ] = {
+		"sccp:n_connect:req",
+		"Submit SCCP N-CONNECT.req (UL SCCP CR)"
+	},
+	[CNLINK_CTR_SCCP_N_CONNECT_CNF] = {
+		"sccp:n_connect:cnf",
+		"Received SCCP N-CONNECT.cnf (DL SCCP CC)"
+	},
+	[CNLINK_CTR_SCCP_N_DATA_REQ] = {
+		"sccp:n_data:req",
+		"SUBMIT SCCP N-DATA.req (UL)"
+	},
+	[CNLINK_CTR_SCCP_N_DATA_IND] = {
+		"sccp:n_data:ind",
+		"Received SCCP N-DATA.ind (DL)"
+	},
+	[CNLINK_CTR_SCCP_N_DISCONNECT_REQ] = {
+		"sccp:n_disconnect:req",
+		"Submit SCCP N-DISCONNECT.req (UL SCCP RLC)"
+	},
+	[CNLINK_CTR_SCCP_N_DISCONNECT_IND] = {
+		"sccp:n_disconnect:ind",
+		"Received SCCP N-DISCONNECT.ind (DL SCCP RLSD)"
+	},
+	[CNLINK_CTR_SCCP_N_PCSTATE_IND] = {
+		"sccp:n_pcstate:ind",
+		"Received SCCP N-PCSTATE.ind"
+	},
+	[CNLINK_CTR_SCCP_RLSD_CN_ORIGIN] = {
+		"sccp:rlsd_cn_origin",
+		"Received unexpected SCCP RSLD originated unilaterally by CN"
+	},
+
+	/* Indicators for CN pool usage */
+	[CNLINK_CTR_CNPOOL_SUBSCR_NEW] = {
+		"cnpool:subscr:new",
+		"Complete Layer 3 requests assigned to this CN link by round-robin (no NRI was assigned yet).",
+	},
+	[CNLINK_CTR_CNPOOL_SUBSCR_REATTACH] = {
+		"cnpool:subscr:reattach",
+		"Complete Layer 3 requests assigned to this CN link by round-robin because the subscriber indicates a"
+		" NULL-NRI (previously assigned by another CN link).",
+	},
+	[CNLINK_CTR_CNPOOL_SUBSCR_KNOWN] = {
+		"cnpool:subscr:known",
+		"Complete Layer 3 requests directed to this CN link because the subscriber indicates an NRI of this CN link.",
+	},
+	[CNLINK_CTR_CNPOOL_SUBSCR_PAGED] = {
+		"cnpool:subscr:paged",
+		"Paging Response directed to this CN link because the subscriber was recently paged by this CN link.",
+	},
+	[CNLINK_CTR_CNPOOL_SUBSCR_ATTACH_LOST] = {
+		"cnpool:subscr:attach_lost",
+		"A subscriber indicates an NRI value matching this CN link, but the CN link is not connected:"
+		" a re-attach to another CN link (if available) was forced, with possible service failure.",
+	},
+	[CNLINK_CTR_CNPOOL_EMERG_FORWARDED] = {
+		"cnpool:emerg:forwarded",
+		"Emergency call requests forwarded to this CN link.",
+	},
+};
+
+static const struct rate_ctr_group_desc msc_ctrg_desc = {
+	"msc",
+	"MSC",
+	OSMO_STATS_CLASS_GLOBAL,
+	ARRAY_SIZE(cnlink_ctr_description),
+	cnlink_ctr_description,
+};
+
+static const struct rate_ctr_group_desc sgsn_ctrg_desc = {
+	"sgsn",
+	"SGSN",
+	OSMO_STATS_CLASS_GLOBAL,
+	ARRAY_SIZE(cnlink_ctr_description),
+	cnlink_ctr_description,
+};
+
+static const struct osmo_stat_item_desc cnlink_stat_desc[] = {
+	[CNLINK_STAT_CONNECTED] = { "connected", "Connected (1) or disconnected (0)", NULL, 60, 0 },
+};
+
+const struct osmo_stat_item_group_desc msc_statg_desc = {
+	.group_name_prefix = "msc",
+	.group_description = "MSC",
+	.class_id = OSMO_STATS_CLASS_GLOBAL,
+	.num_items = ARRAY_SIZE(cnlink_stat_desc),
+	.item_desc = cnlink_stat_desc,
+};
+
+const struct osmo_stat_item_group_desc sgsn_statg_desc = {
+	.group_name_prefix = "sgsn",
+	.group_description = "SGSN",
+	.class_id = OSMO_STATS_CLASS_GLOBAL,
+	.num_items = ARRAY_SIZE(cnlink_stat_desc),
+	.item_desc = cnlink_stat_desc,
+};
+
+struct hnbgw_cnlink *hnbgw_cnlink_alloc(struct hnbgw_cnpool *cnpool, int nr)
+{
+	struct hnbgw_cnlink *cnlink;
+	const struct rate_ctr_group_desc *ctrg_desc;
+	const struct osmo_stat_item_group_desc *statg_desc;
+
+	OSMO_ASSERT(cnpool);
+
+	switch (cnpool->domain) {
+	case DOMAIN_CS:
+		ctrg_desc = &msc_ctrg_desc;
+		statg_desc = &msc_statg_desc;
+		break;
+	case DOMAIN_PS:
+		ctrg_desc = &sgsn_ctrg_desc;
+		statg_desc = &sgsn_statg_desc;
+		break;
+	default:
+		OSMO_ASSERT(0);
+	}
+
+	cnlink = talloc_zero(cnpool, struct hnbgw_cnlink);
+	OSMO_ASSERT(cnlink);
+	*cnlink = (struct hnbgw_cnlink){
+		.pool = cnpool,
+		.nr = nr,
+		.vty = {
+			/* VTY config defaults for the new cnlink */
+			.nri_ranges = osmo_nri_ranges_alloc(cnlink),
+		},
+		.allow_attach = true,
+		.ctrs = rate_ctr_group_alloc(cnlink, ctrg_desc, nr),
+		.statg = osmo_stat_item_group_alloc(cnlink, statg_desc, nr),
+	};
+	cnlink->name = talloc_asprintf(cnlink, "%s-%d", cnpool->peer_name, nr);
+	INIT_LLIST_HEAD(&cnlink->map_list);
+	INIT_LLIST_HEAD(&cnlink->paging);
+
+	cnlink->fi = osmo_fsm_inst_alloc(&cnlink_fsm, cnlink, cnlink, LOGL_DEBUG, cnlink->name);
+	OSMO_ASSERT(cnlink->fi);
+
+	llist_add_tail(&cnlink->entry, &cnpool->cnlinks);
+	LOG_CNLINK(cnlink, DCN, LOGL_DEBUG, "allocated\n");
+
+	cnlink_resend_reset(cnlink);
+	return cnlink;
+}
+
+int hnbgw_cnlink_set_name(struct hnbgw_cnlink *cnlink, const char *name)
+{
+	talloc_free(cnlink->name);
+	cnlink->name = talloc_strdup(cnlink, name);
+	osmo_fsm_inst_update_id_f_sanitize(cnlink->fi, '-', cnlink->name);
+	/* Update rate_ctr/stats to report by name instead of index: */
+	rate_ctr_group_set_name(cnlink->ctrs, cnlink->name);
+	osmo_stat_item_group_set_name(cnlink->statg, cnlink->name);
+	return 0;
+}
+
+void hnbgw_cnlink_drop_sccp(struct hnbgw_cnlink *cnlink)
+{
+	struct hnbgw_context_map *map, *map2;
+	struct hnbgw_sccp_user *hsu;
+
+	llist_for_each_entry_safe(map, map2, &cnlink->map_list, hnbgw_cnlink_entry) {
+		map_sccp_dispatch(map, MAP_SCCP_EV_USER_ABORT, NULL);
+	}
+
+	OSMO_ASSERT(cnlink->hnbgw_sccp_user);
+	hsu = cnlink->hnbgw_sccp_user;
+	cnlink->hnbgw_sccp_user = NULL;
+	hnbgw_sccp_user_put(hsu, HSU_USE_CNLINK);
+}
+
+void hnbgw_cnlink_term_and_free(struct hnbgw_cnlink *cnlink)
+{
+	if (!cnlink)
+		return;
+
+	if (cnlink->hnbgw_sccp_user)
+		hnbgw_cnlink_drop_sccp(cnlink);
+
+	osmo_fsm_inst_term(cnlink->fi, OSMO_FSM_TERM_REQUEST, NULL);
+	cnlink->fi = NULL;
+	osmo_stat_item_group_free(cnlink->statg);
+	rate_ctr_group_free(cnlink->ctrs);
+	llist_del(&cnlink->entry);
+	talloc_free(cnlink);
+}
+
+static int hnbgw_cnlink_tx_sccp_unitdata_req(struct hnbgw_cnlink *cnlink, struct msgb *msg)
+{
+	CNLINK_CTR_INC(cnlink, CNLINK_CTR_SCCP_N_UNITDATA_REQ);
+	return hnbgw_sccp_user_tx_unitdata_req(cnlink->hnbgw_sccp_user,
+					       &cnlink->remote_addr,
+					       msg);
+}
+
+int hnbgw_cnlink_tx_ranap_reset(struct hnbgw_cnlink *cnlink)
+{
+	struct msgb *msg;
+	RANAP_Cause_t cause = {
+		.present = RANAP_Cause_PR_transmissionNetwork,
+		.choice. transmissionNetwork = RANAP_CauseTransmissionNetwork_signalling_transport_resource_failure,
+	};
+	RANAP_GlobalRNC_ID_t grnc_id;
+	RANAP_GlobalRNC_ID_t *use_grnc_id = NULL;
+	uint8_t plmn_buf[3];
+
+	if (!cnlink)
+		return -1;
+
+	/* We need to have chosen an SCCP instance, and the remote SCCP address needs to be set.
+	 * Only check the remote_addr, allowing use.remote_addr_name to be NULL: if the user has not set an explicit
+	 * remote address book entry, auto-configuration may still have chosen a default remote point-code. */
+	if (!cnlink->hnbgw_sccp_user
+	    || !osmo_sccp_check_addr(&cnlink->remote_addr, OSMO_SCCP_ADDR_T_PC | OSMO_SCCP_ADDR_T_SSN)) {
+		LOG_CNLINK(cnlink, DRANAP, LOGL_DEBUG, "not yet configured, not sending RANAP RESET\n");
+		return -1;
+	}
+
+	LOG_CNLINK(cnlink, DRANAP, LOGL_DEBUG, "Tx RANAP RESET to %s %s\n",
+		   cnlink_is_cs(cnlink) ? "IuCS" : "IuPS",
+		   hnbgw_cnlink_sccp_addr_to_str(cnlink, &cnlink->remote_addr));
+
+	if (g_hnbgw->config.plmn.mcc) {
+		osmo_plmn_to_bcd(plmn_buf, &g_hnbgw->config.plmn);
+		grnc_id = (RANAP_GlobalRNC_ID_t){
+			.pLMNidentity = {
+				.buf = plmn_buf,
+				.size = 3,
+			},
+			.rNC_ID = g_hnbgw->config.rnc_id,
+		};
+		use_grnc_id = &grnc_id;
+	} else {
+		/* If no PLMN is configured, omit the Global RNC Id from the RESET message.
+		 *
+		 * According to 3GPP TS 25.413 8.26.2.2, "The RNC shall include the Global RNC-ID IE in the RESET
+		 * message", so it should be considered a mandatory IE when coming from us, the RNC.
+		 *
+		 * But osmo-hnbgw < v1.5 worked well with osmo-hnbgw.cfg files that have no PLMN configured, and we are
+		 * trying to stay backwards compatible for those users. Such a site should still work, but they should
+		 * now see these error logs and can adjust the config.
+		 */
+		LOG_CNLINK(cnlink, DRANAP, LOGL_ERROR,
+			   "No local PLMN is configured, so outgoing RESET messages omit the mandatory Global RNC-ID"
+			   " IE. You should set a 'hnbgw' / 'plmn' in your config file (since v1.5)\n");
+	}
+
+	msg = ranap_new_msg_reset2(cnlink->pool->domain, &cause, use_grnc_id);
+	CNLINK_CTR_INC(cnlink, CNLINK_CTR_RANAP_TX_UDT_RESET);
+	return hnbgw_cnlink_tx_sccp_unitdata_req(cnlink, msg);
+}
+
+int hnbgw_cnlink_tx_ranap_reset_ack(struct hnbgw_cnlink *cnlink)
+{
+	struct msgb *msg;
+	struct osmo_sccp_instance *sccp = hnbgw_cnlink_sccp(cnlink);
+	RANAP_GlobalRNC_ID_t grnc_id;
+	RANAP_GlobalRNC_ID_t *use_grnc_id = NULL;
+	uint8_t plmn_buf[3];
+
+	if (!sccp) {
+		LOG_CNLINK(cnlink, DRANAP, LOGL_ERROR, "cannot send RANAP RESET ACK: no CN link\n");
+		return -1;
+	}
+
+	LOG_CNLINK(cnlink, DRANAP, LOGL_NOTICE, "Tx RANAP RESET ACK %s %s --> %s\n",
+		   cnlink_is_cs(cnlink) ? "IuCS" : "IuPS",
+		   hnbgw_cnlink_sccp_addr_to_str(cnlink, &cnlink->hnbgw_sccp_user->local_addr),
+		   hnbgw_cnlink_sccp_addr_to_str(cnlink, &cnlink->remote_addr));
+
+	if (g_hnbgw->config.plmn.mcc) {
+		osmo_plmn_to_bcd(plmn_buf, &g_hnbgw->config.plmn);
+		grnc_id = (RANAP_GlobalRNC_ID_t){
+			.pLMNidentity = {
+				.buf = plmn_buf,
+				.size = 3,
+			},
+			.rNC_ID = g_hnbgw->config.rnc_id,
+		};
+		use_grnc_id = &grnc_id;
+	} else {
+		/* If no PLMN is configured, omit the Global RNC Id from the RESET ACK message.
+		 *
+		 * According to 3GPP TS 25.413 8.26.2.1, "The RNC shall include the Global RNC-ID IE in the RESET
+		 * ACKNOWLEDGE message", so it should be considered a mandatory IE when coming from us, the RNC.
+		 *
+		 * But osmo-hnbgw < v1.5 worked well with osmo-hnbgw.cfg files that have no PLMN configured, and we are
+		 * trying to stay backwards compatible for those users. Such a site should still work, but they should
+		 * now see these error logs and can adjust the config.
+		 */
+		LOG_CNLINK(cnlink, DRANAP, LOGL_ERROR,
+			   "No local PLMN is configured, so outgoing RESET ACKNOWLEDGE messages omit the mandatory"
+			   " Global RNC-ID IE. You should set a 'hnbgw' / 'plmn' in your config file (since v1.5)\n");
+	}
+
+	msg = ranap_new_msg_reset_ack(cnlink->pool->domain, use_grnc_id);
+	CNLINK_CTR_INC(cnlink, CNLINK_CTR_RANAP_TX_UDT_RESET_ACK);
+	return hnbgw_cnlink_tx_sccp_unitdata_req(cnlink, msg);
+}
+
+/* Return address found in sccp address-book, and fill in missing fields in the
+ * entry with default values. */
+static struct osmo_ss7_instance *sccp_addr_by_name_filled(struct osmo_sccp_addr *dest, const char *addr_name, uint32_t default_pc)
+{
+	struct osmo_ss7_instance *s7i;
+	s7i = osmo_sccp_addr_by_name(dest, addr_name);
+	if (!s7i)
+		return NULL;
+
+	/* Address exists in address-book but may not be filled entirely: */
+	if (!dest->presence)
+		osmo_sccp_make_addr_pc_ssn(dest, default_pc, OSMO_SCCP_SSN_RANAP);
+	else if (!(dest->presence & OSMO_SCCP_ADDR_T_SSN))
+		osmo_sccp_addr_set_ssn(dest, OSMO_SCCP_SSN_RANAP);
+
+	return s7i;
+}
+
+char *hnbgw_cnlink_sccp_addr_to_str(struct hnbgw_cnlink *cnlink, const struct osmo_sccp_addr *addr)
+{
+	struct osmo_sccp_instance *sccp = hnbgw_cnlink_sccp(cnlink);
+	if (!sccp)
+		return osmo_sccp_addr_dump(addr);
+	return osmo_sccp_inst_addr_to_str_c(OTC_SELECT, sccp, addr);
+}
+
+static void hnbgw_cnlink_cfg_copy(struct hnbgw_cnlink *cnlink)
+{
+	struct osmo_nri_range *r;
+
+	osmo_talloc_replace_string(cnlink, &cnlink->use.remote_addr_name, cnlink->vty.remote_addr_name);
+
+	osmo_nri_ranges_free(cnlink->use.nri_ranges);
+	cnlink->use.nri_ranges = osmo_nri_ranges_alloc(cnlink);
+	llist_for_each_entry(r, &cnlink->vty.nri_ranges->entries, entry)
+		osmo_nri_ranges_add(cnlink->use.nri_ranges, r);
+}
+
+static bool hnbgw_cnlink_sccp_cfg_changed(struct hnbgw_cnlink *cnlink)
+{
+	bool changed = false;
+
+	if (cnlink->vty.remote_addr_name && cnlink->use.remote_addr_name) {
+		struct osmo_ss7_instance *s7i;
+		struct osmo_sccp_addr remote_addr = {};
+
+		/* Instead of comparing whether the address book entry names are different, actually resolve the
+		 * resulting SCCP address, and only restart the cnlink if the resulting address changed. */
+		s7i = sccp_addr_by_name_filled(&remote_addr, cnlink->vty.remote_addr_name,
+					       cnlink->pool->default_remote_pc);
+		if (!s7i)
+			return true;
+		if (osmo_sccp_addr_cmp(&remote_addr, &cnlink->remote_addr,
+				      OSMO_SCCP_ADDR_T_PC | OSMO_SCCP_ADDR_T_SSN))
+			changed = true;
+	} else if (cnlink->vty.remote_addr_name != cnlink->use.remote_addr_name) {
+		/* One of them is NULL, the other is not. */
+		changed = true;
+	}
+
+	/* if more cnlink configuration is added in the future, it needs to be compared here. */
+	return changed;
+}
+
+static void hnbgw_cnlink_log_self(struct hnbgw_cnlink *cnlink)
+{
+	struct osmo_ss7_instance *ss7 = cnlink->hnbgw_sccp_user->ss7;
+	LOG_CNLINK(cnlink, DCN, LOGL_NOTICE, "using: cs7-%u %s <-> %s %s %s\n",
+		   osmo_ss7_instance_get_id(ss7),
+		   /* printing the entire SCCP address is quite long, rather just print the point-code */
+		   osmo_ss7_pointcode_print(ss7, cnlink->hnbgw_sccp_user->local_addr.pc),
+		   osmo_ss7_pointcode_print2(ss7, cnlink->remote_addr.pc),
+		   cnlink->name, cnlink->use.remote_addr_name ? : "(default remote point-code)");
+}
+
+/* If not present yet, set up all of osmo_ss7_instance, osmo_sccp_instance and hnbgw_sccp_user for the given cnlink.
+ * The cs7 instance nr to use is determined by cnlink->remote_addr_name, or cs7 instance 0 if that is not present.
+ * Set cnlink->hnbgw_sccp_user to the new SCCP instance. Return 0 on success, negative on error. */
+int hnbgw_cnlink_start_or_restart(struct hnbgw_cnlink *cnlink)
+{
+	struct osmo_ss7_instance *s7i = NULL;
+	struct hnbgw_sccp_user *hsu;
+	uint32_t ss7_id;
+	int rc;
+
+	/* If a hnbgw_sccp_user has already been set up, use that. */
+	if (cnlink->hnbgw_sccp_user) {
+		if (!hnbgw_cnlink_sccp_cfg_changed(cnlink)) {
+			LOG_CNLINK(cnlink, DCN, LOGL_DEBUG, "SCCP instance already set up, using %s\n",
+				   cnlink->hnbgw_sccp_user->name);
+			return 0;
+		}
+		LOG_CNLINK(cnlink, DCN, LOGL_NOTICE, "config changed, restarting SCCP\n");
+		hnbgw_cnlink_drop_sccp(cnlink);
+	} else {
+		LOG_CNLINK(cnlink, DCN, LOGL_DEBUG, "no SCCP instance selected yet\n");
+	}
+
+	/* Copy the current configuration: cnlink->use = cnlink->vty */
+	hnbgw_cnlink_cfg_copy(cnlink);
+
+	if (!cnlink->use.remote_addr_name) {
+		/* No remote address configured in VTY, set a default one and
+		 * make sure it becomes registered in the sccp address-book: */
+		cnlink->use.remote_addr_name = talloc_strdup(cnlink, cnlink->pool->default_addr_name);
+		s7i = osmo_sccp_addr_by_name(&cnlink->remote_addr, cnlink->use.remote_addr_name);
+		if (!s7i) {
+			LOG_CNLINK(cnlink, DCN, LOGL_NOTICE, "To auto-configure cnlink, creating cs7 instance 0 implicitly\n");
+			s7i = osmo_ss7_instance_find_or_create(g_hnbgw, 0);
+			OSMO_ASSERT(s7i);
+			osmo_sccp_make_addr_pc_ssn(&cnlink->remote_addr,
+						   cnlink->pool->default_remote_pc,
+						   OSMO_SCCP_SSN_RANAP);
+			rc = osmo_sccp_addr_create(s7i, cnlink->use.remote_addr_name, &cnlink->remote_addr);
+			if (rc < 0) {
+				LOG_CNLINK(cnlink, DCN, LOGL_ERROR, "Failed adding address '%s' to sccp address-book!\n",
+					   cnlink->use.remote_addr_name);
+				return -EINVAL;
+			}
+		}
+		/* Update VTY config to show & point to the address dynamically added to address-book: */
+		cnlink->vty.remote_addr_name = talloc_strdup(cnlink, cnlink->use.remote_addr_name);
+	} else {
+		s7i = sccp_addr_by_name_filled(&cnlink->remote_addr, cnlink->use.remote_addr_name, cnlink->pool->default_remote_pc);
+		if (!s7i) {
+			LOG_CNLINK(cnlink, DCN, LOGL_ERROR, "cannot initialize SCCP: there is no SCCP address named '%s'\n",
+				   cnlink->use.remote_addr_name);
+			return -ENOENT;
+		}
+		LOG_CNLINK(cnlink, DCN, LOGL_DEBUG, "remote-addr is '%s', using cs7 instance %u\n",
+			   cnlink->use.remote_addr_name, osmo_ss7_instance_get_id(s7i));
+		/* Address exists in address-book but may not be filled entirely: */
+		rc = osmo_sccp_addr_update(s7i, cnlink->use.remote_addr_name, &cnlink->remote_addr);
+		if (rc < 0) {
+			LOG_CNLINK(cnlink, DCN, LOGL_ERROR, "Failed updating address '%s' in sccp address-book!\n",
+				   cnlink->use.remote_addr_name);
+			return -EINVAL;
+		}
+	}
+
+	ss7_id = osmo_ss7_instance_get_id(s7i);
+
+	/* Has another cnlink already set up an SCCP instance for this s7i? */
+	llist_for_each_entry(hsu, &g_hnbgw->sccp.users, entry) {
+		if (hsu->ss7 != s7i)
+			continue;
+		LOG_CNLINK(cnlink, DCN, LOGL_DEBUG, "using existing SCCP instance %s on cs7 instance %u\n",
+			hsu->name, ss7_id);
+		cnlink->hnbgw_sccp_user = hsu;
+		hnbgw_sccp_user_get(cnlink->hnbgw_sccp_user, HSU_USE_CNLINK);
+		hnbgw_cnlink_log_self(cnlink);
+		return 0;
+	}
+	/* else cnlink->hnbgw_sccp_user stays NULL and is set up below. */
+	LOG_CNLINK(cnlink, DCN, LOGL_DEBUG, "cs7 instance %u has no configured SCCP instance yet\n", ss7_id);
+
+	/* No SCCP instance yet for this ss7. Create it. If no address name is given that resolves to a
+	 * particular cs7 instance above, use 'cs7 instance 0'. */
+	cnlink->hnbgw_sccp_user = hnbgw_sccp_user_alloc(ss7_id);
+	hnbgw_sccp_user_get(cnlink->hnbgw_sccp_user, HSU_USE_CNLINK);
+	hnbgw_cnlink_log_self(cnlink);
+	return 0;
+}

src/osmo-hnbgw/cnlink_fsm.c

@@ -0,0 +1,220 @@
+/* (C) 2023 by sysmocom s.f.m.c. GmbH <info@sysmocom.de>
+ * All Rights Reserved
+ *
+ * Author: Neels Hofmeyr
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include <osmocom/core/fsm.h>
+#include <osmocom/core/tdef.h>
+
+#include <osmocom/gsm/gsm23236.h>
+
+#include <osmocom/sigtran/sccp_helpers.h>
+
+#include <asn1c/asn1helpers.h>
+#include <osmocom/ranap/ranap_ies_defs.h>
+#include <osmocom/ranap/ranap_msg_factory.h>
+
+#include <osmocom/hnbgw/hnbgw.h>
+#include <osmocom/hnbgw/hnbgw_cn.h>
+#include <osmocom/hnbgw/tdefs.h>
+#include <osmocom/hnbgw/context_map.h>
+
+enum cnlink_fsm_state {
+	CNLINK_ST_DISC,
+	CNLINK_ST_CONN,
+};
+
+enum cnlink_fsm_event {
+	CNLINK_EV_RX_RESET,
+	CNLINK_EV_RX_RESET_ACK,
+};
+
+static const struct value_string cnlink_fsm_event_names[] = {
+	OSMO_VALUE_STRING(CNLINK_EV_RX_RESET),
+	OSMO_VALUE_STRING(CNLINK_EV_RX_RESET_ACK),
+	{}
+};
+
+static const struct osmo_tdef_state_timeout cnlink_timeouts[32] = {
+	[CNLINK_ST_DISC] = { .T = 4 },
+};
+
+#define cnlink_fsm_state_chg(FI, STATE) \
+	osmo_tdef_fsm_inst_state_chg(FI, STATE, \
+				     cnlink_timeouts, \
+				     hnbgw_T_defs, \
+				     -1)
+
+static void link_up(struct hnbgw_cnlink *cnlink)
+{
+	LOGPFSML(cnlink->fi, LOGL_NOTICE, "link up\n");
+	CNLINK_STAT_SET(cnlink, CNLINK_STAT_CONNECTED, 1);
+}
+
+static void link_lost(struct hnbgw_cnlink *cnlink)
+{
+	struct hnbgw_context_map *map, *map2;
+
+	LOGPFSML(cnlink->fi, LOGL_NOTICE, "link lost\n");
+	CNLINK_STAT_SET(cnlink, CNLINK_STAT_CONNECTED, 0);
+
+	llist_for_each_entry_safe(map, map2, &cnlink->map_list, hnbgw_cnlink_entry)
+		context_map_cnlink_lost(map);
+}
+
+
+static void cnlink_disc_onenter(struct osmo_fsm_inst *fi, uint32_t prev_state)
+{
+	struct hnbgw_cnlink *cnlink = (struct hnbgw_cnlink *)fi->priv;
+	if (prev_state == CNLINK_ST_CONN)
+		link_lost(cnlink);
+}
+
+static void cnlink_disc_action(struct osmo_fsm_inst *fi, uint32_t event, void *data)
+{
+	struct hnbgw_cnlink *cnlink = (struct hnbgw_cnlink *)fi->priv;
+	switch (event) {
+
+	case CNLINK_EV_RX_RESET:
+		hnbgw_cnlink_tx_ranap_reset_ack(cnlink);
+		cnlink_fsm_state_chg(fi, CNLINK_ST_CONN);
+		break;
+
+	case CNLINK_EV_RX_RESET_ACK:
+		cnlink_fsm_state_chg(fi, CNLINK_ST_CONN);
+		break;
+
+	default:
+		OSMO_ASSERT(false);
+	}
+}
+
+static void cnlink_conn_onenter(struct osmo_fsm_inst *fi, uint32_t prev_state)
+{
+	struct hnbgw_cnlink *cnlink = (struct hnbgw_cnlink *)fi->priv;
+	if (prev_state != CNLINK_ST_CONN)
+		link_up(cnlink);
+}
+
+static void cnlink_conn_action(struct osmo_fsm_inst *fi, uint32_t event, void *data)
+{
+	struct hnbgw_cnlink *cnlink = (struct hnbgw_cnlink *)fi->priv;
+
+	switch (event) {
+
+	case CNLINK_EV_RX_RESET:
+		/* We were connected, but the remote side has restarted. */
+		link_lost(cnlink);
+		hnbgw_cnlink_tx_ranap_reset_ack(cnlink);
+		link_up(cnlink);
+		break;
+
+	case CNLINK_EV_RX_RESET_ACK:
+		LOGPFSML(fi, LOGL_INFO, "Link is already up, ignoring RESET ACK\n");
+		break;
+
+	default:
+		OSMO_ASSERT(false);
+	}
+}
+
+static int cnlink_fsm_timer_cb(struct osmo_fsm_inst *fi)
+{
+	struct hnbgw_cnlink *cnlink = (struct hnbgw_cnlink *)fi->priv;
+
+	hnbgw_cnlink_tx_ranap_reset(cnlink);
+
+	/* (re-)enter disconnect state to resend RESET after timeout. */
+	cnlink_fsm_state_chg(fi, CNLINK_ST_DISC);
+
+	/* Return 0 to not terminate the fsm */
+	return 0;
+}
+
+#define S(x) (1 << (x))
+
+static struct osmo_fsm_state cnlink_fsm_states[] = {
+	[CNLINK_ST_DISC] = {
+		     .name = "DISCONNECTED",
+		     .in_event_mask = 0
+			     | S(CNLINK_EV_RX_RESET)
+			     | S(CNLINK_EV_RX_RESET_ACK)
+			     ,
+		     .out_state_mask = 0
+			     | S(CNLINK_ST_DISC)
+			     | S(CNLINK_ST_CONN)
+			     ,
+		     .onenter = cnlink_disc_onenter,
+		     .action = cnlink_disc_action,
+		     },
+	[CNLINK_ST_CONN] = {
+		     .name = "CONNECTED",
+		     .in_event_mask = 0
+			     | S(CNLINK_EV_RX_RESET)
+			     | S(CNLINK_EV_RX_RESET_ACK)
+			     ,
+		     .out_state_mask = 0
+			     | S(CNLINK_ST_DISC)
+			     | S(CNLINK_ST_CONN)
+			     ,
+		     .onenter = cnlink_conn_onenter,
+		     .action = cnlink_conn_action,
+		     },
+};
+
+struct osmo_fsm cnlink_fsm = {
+	.name = "cnlink",
+	.states = cnlink_fsm_states,
+	.num_states = ARRAY_SIZE(cnlink_fsm_states),
+	.log_subsys = DRANAP,
+	.timer_cb = cnlink_fsm_timer_cb,
+	.event_names = cnlink_fsm_event_names,
+};
+
+bool cnlink_is_conn_ready(const struct hnbgw_cnlink *cnlink)
+{
+	return cnlink->fi->state == CNLINK_ST_CONN;
+}
+
+void cnlink_resend_reset(struct hnbgw_cnlink *cnlink)
+{
+	/* Immediately (1ms) kick off reset sending mechanism */
+	osmo_fsm_inst_state_chg_ms(cnlink->fi, CNLINK_ST_DISC, 1, 0);
+}
+
+void cnlink_set_disconnected(struct hnbgw_cnlink *cnlink)
+{
+	/* Go to disconnected state, with the normal RESET timeout to re-send RESET. */
+	cnlink_fsm_state_chg(cnlink->fi, CNLINK_ST_DISC);
+}
+
+static __attribute__((constructor)) void cnlink_fsm_init(void)
+{
+	OSMO_ASSERT(osmo_fsm_register(&cnlink_fsm) == 0);
+}
+
+void cnlink_rx_reset_cmd(struct hnbgw_cnlink *cnlink)
+{
+	osmo_fsm_inst_dispatch(cnlink->fi, CNLINK_EV_RX_RESET, NULL);
+}
+
+void cnlink_rx_reset_ack(struct hnbgw_cnlink *cnlink)
+{
+	osmo_fsm_inst_dispatch(cnlink->fi, CNLINK_EV_RX_RESET_ACK, NULL);
+}
+

src/osmo-hnbgw/cnlink_paging.c

@@ -0,0 +1,230 @@
+/* RANAP Paging of HNB-GW */
+/* (C) 2015 by Harald Welte <laforge@gnumonks.org>
+ * (C) 2025 by sysmocom - s.f.m.c. GmbH <info@sysmocom.de>
+ * All Rights Reserved
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include "config.h"
+
+#include <errno.h>
+#include <sys/types.h>
+
+#include <asn1c/asn1helpers.h>
+
+#include <osmocom/core/logging.h>
+#include <osmocom/core/timer.h>
+#include <osmocom/core/utils.h>
+#include <osmocom/core/linuxlist.h>
+#include <osmocom/gsm/gsm48.h>
+
+#include <osmocom/ranap/ranap_ies_defs.h>
+#include <osmocom/ranap/iu_helpers.h>
+
+#include <osmocom/hnbgw/hnbgw.h>
+#include <osmocom/hnbgw/hnbgw_cn.h>
+#include <osmocom/hnbgw/context_map.h>
+#include <osmocom/hnbgw/tdefs.h>
+
+/***************
+ * This module manages the list of "struct cnlink_paging" items in (struct
+ * hnbgw_cnlink *)->paging.
+ * Every time a new RANAP Paging Cmd arrives from some cnlink,
+ * cnlink_paging_add_ranap() is called to potentially store the paging command
+ * for a while.
+ * When a paging response is received from HNB, cnlink_find_by_paging_mi() is
+ * called to obtain the cnlink it should be routed back to.
+ */
+
+struct cnlink_paging {
+	struct llist_head entry;
+
+	struct osmo_mobile_identity mi;
+	struct osmo_mobile_identity mi2;
+	time_t timestamp;
+};
+
+static int cnlink_paging_destructor(struct cnlink_paging *p)
+{
+	llist_del(&p->entry);
+	return 0;
+}
+
+
+/* Return current timestamp in *timestamp, and the oldest still valid timestamp according to T3113 timeout. */
+static const char *cnlink_paging_gettime(time_t *timestamp_p, time_t *timeout_p)
+{
+	struct timespec now;
+	time_t timestamp;
+
+	/* get timestamp */
+	if (osmo_clock_gettime(CLOCK_MONOTONIC, &now) != 0)
+		return "cannot get timestamp";
+	timestamp = now.tv_sec;
+
+	if (timestamp_p)
+		*timestamp_p = timestamp;
+	if (timeout_p)
+		*timeout_p = timestamp - osmo_tdef_get(hnbgw_T_defs, 3113, OSMO_TDEF_S, 15);
+	return NULL;
+}
+
+static const char *cnlink_paging_add(struct hnbgw_cnlink *cnlink, const struct osmo_mobile_identity *mi,
+				     const struct osmo_mobile_identity *mi2)
+{
+	struct cnlink_paging *p, *p2;
+	time_t timestamp;
+	time_t timeout;
+	const char *errmsg;
+
+	errmsg = cnlink_paging_gettime(&timestamp, &timeout);
+	if (errmsg)
+		return errmsg;
+
+	/* Prune all paging records that are older than the configured timeout. */
+	llist_for_each_entry_safe(p, p2, &cnlink->paging, entry) {
+		if (p->timestamp >= timeout)
+			continue;
+		talloc_free(p);
+	}
+
+	/* Add new entry */
+	p = talloc_zero(cnlink, struct cnlink_paging);
+	*p = (struct cnlink_paging){
+		.timestamp = timestamp,
+		.mi = *mi,
+		.mi2 = *mi2,
+	};
+	llist_add_tail(&p->entry, &cnlink->paging);
+	talloc_set_destructor(p, cnlink_paging_destructor);
+
+	LOG_CNLINK(cnlink, DCN, LOGL_INFO, "Rx Paging from CN for %s %s\n",
+		   osmo_mobile_identity_to_str_c(OTC_SELECT, mi),
+		   osmo_mobile_identity_to_str_c(OTC_SELECT, mi2));
+	return NULL;
+}
+
+static const char *omi_from_ranap_ue_id(struct osmo_mobile_identity *mi, const RANAP_PermanentNAS_UE_ID_t *ranap_mi)
+{
+	if (!ranap_mi)
+		return "null UE ID";
+
+	if (ranap_mi->present != RANAP_PermanentNAS_UE_ID_PR_iMSI)
+		return talloc_asprintf(OTC_SELECT, "unsupported UE ID type %u in RANAP Paging", ranap_mi->present);
+
+	if (ranap_mi->choice.iMSI.size > sizeof(mi->imsi))
+		return talloc_asprintf(OTC_SELECT, "invalid IMSI size %d > %zu",
+				       ranap_mi->choice.iMSI.size, sizeof(mi->imsi));
+
+	*mi = (struct osmo_mobile_identity){
+		.type = GSM_MI_TYPE_IMSI,
+	};
+	ranap_bcd_decode(mi->imsi, sizeof(mi->imsi), ranap_mi->choice.iMSI.buf, ranap_mi->choice.iMSI.size);
+	LOGP(DCN, LOGL_DEBUG, "ranap MI %s = %s\n", osmo_hexdump(ranap_mi->choice.iMSI.buf, ranap_mi->choice.iMSI.size),
+	     mi->imsi);
+	return NULL;
+}
+
+static const char *omi_from_ranap_temp_ue_id(struct osmo_mobile_identity *mi, const RANAP_TemporaryUE_ID_t *ranap_tmsi)
+{
+	const OCTET_STRING_t *tmsi_str;
+
+	if (!ranap_tmsi)
+		return "null UE ID";
+
+	switch (ranap_tmsi->present) {
+	case RANAP_TemporaryUE_ID_PR_tMSI:
+		tmsi_str = &ranap_tmsi->choice.tMSI;
+		break;
+	case RANAP_TemporaryUE_ID_PR_p_TMSI:
+		tmsi_str = &ranap_tmsi->choice.p_TMSI;
+		break;
+	default:
+		return talloc_asprintf(OTC_SELECT, "unsupported Temporary UE ID type %u in RANAP Paging", ranap_tmsi->present);
+	}
+
+	*mi = (struct osmo_mobile_identity){
+		.type = GSM_MI_TYPE_TMSI,
+		.tmsi = asn1str_to_u32(tmsi_str),
+	};
+	LOGP(DCN, LOGL_DEBUG, "ranap temp UE ID = %s\n", osmo_mobile_identity_to_str_c(OTC_SELECT, mi));
+	return NULL;
+}
+
+const char *cnlink_paging_add_ranap(struct hnbgw_cnlink *cnlink, const RANAP_PagingIEs_t *paging_ies)
+{
+	struct osmo_mobile_identity mi = {};
+	struct osmo_mobile_identity mi2 = {};
+	RANAP_CN_DomainIndicator_t domain;
+	const char *errmsg;
+
+	domain = paging_ies->cN_DomainIndicator;
+	errmsg = omi_from_ranap_ue_id(&mi, &paging_ies->permanentNAS_UE_ID);
+
+	if (!errmsg && (paging_ies->presenceMask & PAGINGIES_RANAP_TEMPORARYUE_ID_PRESENT))
+		errmsg = omi_from_ranap_temp_ue_id(&mi2, &paging_ies->temporaryUE_ID);
+
+	LOG_CNLINK(cnlink, DCN, errmsg ? LOGL_NOTICE : LOGL_DEBUG,
+		   "Decoded Paging: %s %s %s%s%s\n",
+		   ranap_domain_name(domain),
+		   osmo_mobile_identity_to_str_c(OTC_SELECT, &mi),
+		   mi2.type ? osmo_mobile_identity_to_str_c(OTC_SELECT, &mi2) : "-",
+		   errmsg ? " -- MI error: " : "",
+		   errmsg ? : "");
+
+	if (errmsg)
+		return errmsg;
+
+	return cnlink_paging_add(cnlink, &mi, &mi2);
+}
+
+/* If this cnlink has a recent Paging for the given MI, return true and drop the Paging record.
+ * Else return false. */
+static bool cnlink_match_paging_mi(struct hnbgw_cnlink *cnlink, const struct osmo_mobile_identity *mi, time_t timeout)
+{
+	struct cnlink_paging *p, *p2;
+	llist_for_each_entry_safe(p, p2, &cnlink->paging, entry) {
+		if (p->timestamp < timeout) {
+			talloc_free(p);
+			continue;
+		}
+		if (osmo_mobile_identity_cmp(&p->mi, mi)
+		    && osmo_mobile_identity_cmp(&p->mi2, mi))
+			continue;
+		talloc_free(p);
+		return true;
+	}
+	return false;
+}
+
+struct hnbgw_cnlink *cnlink_find_by_paging_mi(struct hnbgw_cnpool *cnpool, const struct osmo_mobile_identity *mi)
+{
+	struct hnbgw_cnlink *cnlink;
+	time_t timeout = 0;
+	const char *errmsg;
+
+	errmsg = cnlink_paging_gettime(NULL, &timeout);
+	if (errmsg)
+		LOGP(DCN, LOGL_ERROR, "%s\n", errmsg);
+
+	llist_for_each_entry(cnlink, &cnpool->cnlinks, entry) {
+		if (!cnlink_match_paging_mi(cnlink, mi, timeout))
+			continue;
+		return cnlink;
+	}
+	return NULL;
+}
+

src/osmo-hnbgw/context_map.c

@@ -19,163 +19,210 @@
  *
  */
 
+#include "config.h"
+
 /* an expired mapping is destroyed  after 1..2 * EXPIRY_TIMER_SECS */
 #define EXPIRY_TIMER_SECS	23
 
 #include <osmocom/core/timer.h>
 
-#include <osmocom/hnbgw/hnbgw.h>
+#include <osmocom/netif/stream.h>
+
+#include <osmocom/sigtran/sccp_helpers.h>
+
+#include <osmocom/hnbgw/hnb.h>
+#include <osmocom/hnbgw/hnbgw_cn.h>
 #include <osmocom/hnbgw/context_map.h>
+#include <osmocom/hnbgw/mgw_fsm.h>
+#include <osmocom/hnbgw/ps_rab_ass_fsm.h>
 
 const struct value_string hnbgw_context_map_state_names[] = {
-	{MAP_S_NULL     , "not-initialized"},
-	{MAP_S_ACTIVE   , "active"},
-	{MAP_S_RESERVED1, "inactive-reserved"},
-	{MAP_S_RESERVED2, "inactive-discard"},
-	{0, NULL}
+	{ MAP_S_CONNECTING, "connecting" },
+	{ MAP_S_ACTIVE, "active" },
+	{ MAP_S_DISCONNECTING, "disconnecting" },
+	{}
 };
 
-/* is a given SCCP USER SAP Connection ID in use for a given CN link? */
-static int cn_id_in_use(struct hnbgw_cnlink *cn, uint32_t id)
+/* Combine the RUA and SCCP states, for VTY reporting only. */
+enum hnbgw_context_map_state context_map_get_state(struct hnbgw_context_map *map)
 {
-	struct hnbgw_context_map *map;
-
-	llist_for_each_entry(map, &cn->map_list, cn_list) {
-		if (map->scu_conn_id == id)
-			return 1;
-	}
-	return 0;
-}
-
-/* try to allocate a new SCCP User SAP Connection ID */
-static int alloc_cn_conn_id(struct hnbgw_cnlink *cn, uint32_t *id_out)
-{
-	uint32_t i;
-	uint32_t id;
-
-	for (i = 0; i < 0xffffffff; i++) {
-		id = cn->next_conn_id++;
-		if (!cn_id_in_use(cn, id)) {
-			*id_out = id;
-			return 1;
-		}
-	}
-	return -1;
+	enum hnbgw_context_map_state rua = map_rua_get_state(map);
+	enum hnbgw_context_map_state sccp = map_sccp_get_state(map);
+	if (rua == MAP_S_ACTIVE && sccp == MAP_S_ACTIVE)
+		return MAP_S_ACTIVE;
+	if (rua == MAP_S_DISCONNECTING || sccp == MAP_S_DISCONNECTING)
+		return MAP_S_DISCONNECTING;
+	return MAP_S_CONNECTING;
 }
 
 /* Map from a HNB + ContextID to the SCCP-side Connection ID */
-struct hnbgw_context_map *
-context_map_alloc_by_hnb(struct hnb_context *hnb, uint32_t rua_ctx_id,
-			 bool is_ps,
-			 struct hnbgw_cnlink *cn_if_new)
+struct hnbgw_context_map *context_map_find_by_rua_ctx_id(struct hnb_context *hnb, uint32_t rua_ctx_id, bool is_ps)
 {
 	struct hnbgw_context_map *map;
-	uint32_t new_scu_conn_id;
 
 	llist_for_each_entry(map, &hnb->map_list, hnb_list) {
-		if (map->state != MAP_S_ACTIVE)
+		if (map->is_ps != is_ps)
 			continue;
-		if (map->cn_link != cn_if_new) {
+
+		/* Matching on RUA context id -- only match for RUA context that has not been disconnected yet. If an
+		 * inactive context map for a rua_ctx_id is still around, we may have two entries for the same
+		 * rua_ctx_id around at the same time. That should only stay until its SCCP side is done releasing. */
+		if (!map_rua_is_active(map))
 			continue;
-		}
-		if (map->rua_ctx_id == rua_ctx_id
-		    && map->is_ps == is_ps) {
-			return map;
-		}
-	}
 
-	if (alloc_cn_conn_id(cn_if_new, &new_scu_conn_id) < 0) {
-		LOGHNB(hnb, DMAIN, LOGL_ERROR, "Unable to allocate CN connection ID\n");
-		return NULL;
-	}
-
-	LOGHNB(hnb, DMAIN, LOGL_INFO, "Creating new Mapping RUA CTX %p/%u <-> SCU Conn ID %p/%u\n",
-		hnb, rua_ctx_id, cn_if_new, new_scu_conn_id);
-
-	/* alloate a new map entry */
-	map = talloc_zero(hnb, struct hnbgw_context_map);
-	map->state = MAP_S_NULL;
-	map->cn_link = cn_if_new;
-	map->hnb_ctx = hnb;
-	map->rua_ctx_id = rua_ctx_id;
-	map->is_ps = is_ps;
-	map->scu_conn_id = new_scu_conn_id;
-
-	/* put it into both lists */
-	llist_add_tail(&map->hnb_list, &hnb->map_list);
-	llist_add_tail(&map->cn_list, &cn_if_new->map_list);
-	map->state = MAP_S_ACTIVE;
-
-	return map;
-}
-
-/* Map from a CN + Connection ID to HNB + Context ID */
-struct hnbgw_context_map *
-context_map_by_cn(struct hnbgw_cnlink *cn, uint32_t scu_conn_id)
-{
-	struct hnbgw_context_map *map;
-
-	llist_for_each_entry(map, &cn->map_list, cn_list) {
-		if (map->state != MAP_S_ACTIVE)
+		if (map->rua_ctx_id != rua_ctx_id)
 			continue;
-		if (map->scu_conn_id == scu_conn_id) {
-			return map;
-		}
+
+		/* Already exists */
+		return map;
 	}
-	/* we don't allocate new mappings in the CN->HNB
-	 * direction, as the RUA=SCCP=SUA connections are always
-	 * established from HNB towards CN. */
-	LOGP(DMAIN, LOGL_NOTICE, "Unable to resolve map for CN " "connection ID %p/%u\n", cn, scu_conn_id);
 	return NULL;
 }
 
-void context_map_deactivate(struct hnbgw_context_map *map)
+struct hnbgw_context_map *context_map_alloc(struct hnb_context *hnb, uint32_t rua_ctx_id, bool is_ps)
 {
-	/* set the state to reserved. We still show up in the list and
-	 * avoid re-allocation of the context-id until we are cleaned up
-	 * by the context_map garbage collector timer */
+	struct hnbgw_context_map *map;
 
-	if (map->state != MAP_S_RESERVED2)
-		map->state = MAP_S_RESERVED1;
+	/* allocate a new map entry now, so we have logging context */
+	map = talloc_zero(hnb, struct hnbgw_context_map);
+	map->hnb_ctx = hnb;
+	map->rua_ctx_id = rua_ctx_id;
+	map->is_ps = is_ps;
+	INIT_LLIST_HEAD(&map->ps_rab_ass_list);
+	INIT_LLIST_HEAD(&map->ps_rab_list);
+
+	map_rua_fsm_alloc(map);
+
+	llist_add_tail(&map->hnb_list, &hnb->map_list);
+
+	LOG_MAP(map, DRUA, LOGL_DEBUG, "New RUA CTX\n");
+	return map;
 }
 
-static struct osmo_timer_list context_map_tmr;
-
-static void context_map_tmr_cb(void *data)
+int context_map_set_cnlink(struct hnbgw_context_map *map, struct hnbgw_cnlink *cnlink_selected)
 {
-	struct hnb_gw *gw = data;
-	struct hnbgw_cnlink *cn = gw->sccp.cnlink;
-	struct hnbgw_context_map *map, *next_map;
+	int new_scu_conn_id;
+	struct hnbgw_sccp_user *hsu;
 
-	DEBUGP(DMAIN, "Running context mapper garbage collection\n");
-	llist_for_each_entry_safe(map, next_map, &cn->map_list, cn_list) {
-		switch (map->state) {
-		case MAP_S_RESERVED1:
-			/* first time we see this reserved
-			 * entry: mark it for stage 2 */
-			map->state = MAP_S_RESERVED2;
-			break;
-		case MAP_S_RESERVED2:
-			/* second time we see this reserved
-			 * entry: remove it */
-			map->state = MAP_S_NULL;
-			llist_del(&map->cn_list);
-			llist_del(&map->hnb_list);
-			talloc_free(map);
-			break;
-		default:
-			break;
-		}
+	/* Allocate new SCCP conn id on the SCCP instance the cnlink is on. */
+	hsu = cnlink_selected->hnbgw_sccp_user;
+	if (!hsu) {
+		LOG_MAP(map, DCN, LOGL_ERROR, "Cannot map RUA context to SCCP: No SCCP instance for CN link %s\n",
+			 cnlink_selected->name);
+		return -EIO;
 	}
-	/* re-schedule this timer */
-	osmo_timer_schedule(&context_map_tmr, EXPIRY_TIMER_SECS, 0);
-}
 
-int context_map_init(struct hnb_gw *gw)
-{
-	context_map_tmr.cb = context_map_tmr_cb;
-	context_map_tmr.data = gw;
-	osmo_timer_schedule(&context_map_tmr, EXPIRY_TIMER_SECS, 0);
+	new_scu_conn_id = osmo_sccp_instance_next_conn_id(osmo_ss7_get_sccp(hsu->ss7));
+	if (new_scu_conn_id < 0) {
+		LOG_MAP(map, DCN, LOGL_ERROR, "Unable to allocate SCCP conn ID on %s\n", hsu->name);
+		return new_scu_conn_id;
+	}
+
+	map->cnlink = cnlink_selected;
+	map->scu_conn_id = new_scu_conn_id;
+	map_sccp_fsm_alloc(map);
+
+	llist_add_tail(&map->hnbgw_cnlink_entry, &cnlink_selected->map_list);
+
+	hash_add(hsu->hnbgw_context_map_by_conn_id, &map->hnbgw_sccp_user_entry, new_scu_conn_id);
+
+	LOGP(DRUA, LOGL_INFO, "New conn: %s '%s' RUA-%u <-> SCCP-%u %s%s%s %s l=%s<->r=%s\n",
+	     osmo_sock_get_name2_c(OTC_SELECT, osmo_stream_srv_get_ofd(map->hnb_ctx->conn)->fd),
+	     hnb_context_name(map->hnb_ctx), map->rua_ctx_id,
+	     new_scu_conn_id,
+	     cnlink_selected->name,
+	     cnlink_selected->use.remote_addr_name ? " " : "",
+	     cnlink_selected->use.remote_addr_name ? : "",
+	     hsu->name,
+	     /* printing the entire SCCP address is quite long, rather just print the point-code */
+	     osmo_ss7_pointcode_print(hsu->ss7, hsu->local_addr.pc),
+	     osmo_ss7_pointcode_print2(hsu->ss7, cnlink_selected->remote_addr.pc)
+	    );
 
 	return 0;
 }
+
+int _map_rua_dispatch(struct hnbgw_context_map *map, uint32_t event, struct msgb *ranap_msg,
+		      const char *file, int line)
+{
+	OSMO_ASSERT(map);
+	if (!map->rua_fi) {
+		LOG_MAP(map, DRUA, LOGL_ERROR, "not ready to receive RUA events\n");
+		return -EINVAL;
+	}
+	return _osmo_fsm_inst_dispatch(map->rua_fi, event, ranap_msg, file, line);
+}
+
+int _map_sccp_dispatch(struct hnbgw_context_map *map, uint32_t event, struct msgb *ranap_msg,
+		       const char *file, int line)
+{
+	OSMO_ASSERT(map);
+	if (!map->sccp_fi) {
+		LOG_MAP(map, DRUA, LOGL_ERROR, "not ready to receive SCCP events\n");
+		return -EINVAL;
+	}
+	return _osmo_fsm_inst_dispatch(map->sccp_fi, event, ranap_msg, file, line);
+}
+
+unsigned int msg_has_l2_data(const struct msgb *msg)
+{
+	return msg && msgb_l2(msg) ? msgb_l2len(msg) : 0;
+}
+
+void context_map_hnb_released(struct hnbgw_context_map *map)
+{
+	/* When a HNB disconnects from RUA, the hnb_context will be freed. This hnbgw_context_map was allocated as a
+	 * child of the hnb_context and would also be deallocated along with the hnb_context. However, the SCCP side for
+	 * this hnbgw_context_map may still be waiting for a graceful release (SCCP RLC). Move this hnbgw_context_map to
+	 * the global hnb_gw talloc ctx, so it can stay around for graceful release / for SCCP timeout.
+	 *
+	 * We could also always allocate hnbgw_context_map under hnb_gw, but it is nice to see which hnb_context owns
+	 * which hnbgw_context_map in a talloc report.
+	 */
+	talloc_steal(g_hnbgw, map);
+
+	/* Tell RUA that the HNB is gone. SCCP release will follow via FSM events. */
+	map_rua_dispatch(map, MAP_RUA_EV_HNB_LINK_LOST, NULL);
+}
+
+void context_map_cnlink_lost(struct hnbgw_context_map *map)
+{
+	map_sccp_dispatch(map, MAP_SCCP_EV_CN_LINK_LOST, NULL);
+}
+
+void context_map_free(struct hnbgw_context_map *map)
+{
+	/* guard against FSM termination infinitely looping back here */
+	if (map->deallocating) {
+		LOG_MAP(map, DMAIN, LOGL_DEBUG, "context_map_free(): already deallocating\n");
+		return;
+	}
+	map->deallocating = true;
+
+	if (map->rua_fi)
+		osmo_fsm_inst_term(map->rua_fi, OSMO_FSM_TERM_REGULAR, NULL);
+	OSMO_ASSERT(map->rua_fi == NULL);
+
+	if (map->sccp_fi)
+		osmo_fsm_inst_term(map->sccp_fi, OSMO_FSM_TERM_REGULAR, NULL);
+	OSMO_ASSERT(map->sccp_fi == NULL);
+
+	if (map->mgw_fi) {
+		mgw_fsm_release(map);
+		OSMO_ASSERT(map->mgw_fi == NULL);
+	}
+
+#if ENABLE_PFCP
+	hnbgw_gtpmap_release(map);
+#endif
+
+	if (map->cnlink) {
+		llist_del(&map->hnbgw_cnlink_entry);
+		hash_del(&map->hnbgw_sccp_user_entry);
+	}
+	if (map->hnb_ctx)
+		llist_del(&map->hnb_list);
+
+	LOG_MAP(map, DMAIN, LOGL_INFO, "Deallocating\n");
+	talloc_free(map);
+}

src/osmo-hnbgw/context_map_rua.c

@@ -0,0 +1,384 @@
+/* RUA side FSM of hnbgw_context_map */
+/* (C) 2023 by sysmocom - s.f.m.c. GmbH <info@sysmocom.de>
+ * All Rights Reserved
+ *
+ * SPDX-License-Identifier: AGPL-3.0+
+ *
+ * Author: Neels Hofmeyr
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include "config.h"
+
+#include <osmocom/core/utils.h>
+#include <osmocom/core/fsm.h>
+
+#include <osmocom/hnbgw/hnb.h>
+#include <osmocom/hnbgw/hnbgw.h>
+#include <osmocom/hnbgw/context_map.h>
+#include <osmocom/hnbgw/tdefs.h>
+#include <osmocom/hnbgw/hnbgw_rua.h>
+#include <osmocom/hnbgw/hnbgw_ranap.h>
+
+enum map_rua_fsm_state {
+	MAP_RUA_ST_INIT,
+	MAP_RUA_ST_CONNECTED,
+	MAP_RUA_ST_DISCONNECTED,
+	MAP_RUA_ST_DISRUPTED,
+};
+
+static const struct value_string map_rua_fsm_event_names[] = {
+	OSMO_VALUE_STRING(MAP_RUA_EV_RX_CONNECT),
+	OSMO_VALUE_STRING(MAP_RUA_EV_RX_DIRECT_TRANSFER),
+	OSMO_VALUE_STRING(MAP_RUA_EV_RX_DISCONNECT),
+	OSMO_VALUE_STRING(MAP_RUA_EV_TX_DIRECT_TRANSFER),
+	OSMO_VALUE_STRING(MAP_RUA_EV_CN_DISC),
+	OSMO_VALUE_STRING(MAP_RUA_EV_HNB_LINK_LOST),
+	{}
+};
+
+static struct osmo_fsm map_rua_fsm;
+
+static const struct osmo_tdef_state_timeout map_rua_fsm_timeouts[32] = {
+	[MAP_RUA_ST_INIT] = { .T = -31 },
+	[MAP_RUA_ST_DISCONNECTED] = { .T = -31 },
+	[MAP_RUA_ST_DISRUPTED] = { .T = -31 },
+};
+
+/* Transition to a state, using the T timer defined in map_rua_fsm_timeouts.
+ * Assumes local variable fi exists. */
+#define map_rua_fsm_state_chg(state) \
+       OSMO_ASSERT(osmo_tdef_fsm_inst_state_chg(fi, state, \
+						map_rua_fsm_timeouts, \
+						hnbgw_T_defs, \
+						5) == 0)
+
+void map_rua_fsm_alloc(struct hnbgw_context_map *map)
+{
+	struct osmo_fsm_inst *fi = osmo_fsm_inst_alloc(&map_rua_fsm, map, map, LOGL_DEBUG, NULL);
+	OSMO_ASSERT(fi);
+	osmo_fsm_inst_update_id_f_sanitize(fi, '-', "%s-%s-RUA-%u", hnb_context_name(map->hnb_ctx),
+					   map->is_ps ? "PS" : "CS", map->rua_ctx_id);
+
+	OSMO_ASSERT(map->rua_fi == NULL);
+	map->rua_fi = fi;
+
+	/* trigger the timeout */
+	map_rua_fsm_state_chg(MAP_RUA_ST_INIT);
+}
+
+enum hnbgw_context_map_state map_rua_get_state(struct hnbgw_context_map *map)
+{
+	if (!map || !map->rua_fi)
+		return MAP_S_DISCONNECTING;
+	switch (map->rua_fi->state) {
+	case MAP_RUA_ST_INIT:
+		return MAP_S_CONNECTING;
+	case MAP_RUA_ST_CONNECTED:
+		return MAP_S_ACTIVE;
+	default:
+	case MAP_RUA_ST_DISCONNECTED:
+	case MAP_RUA_ST_DISRUPTED:
+		return MAP_S_DISCONNECTING;
+	}
+}
+
+bool map_rua_is_active(struct hnbgw_context_map *map)
+{
+	if (!map || !map->rua_fi)
+		return false;
+	switch (map->rua_fi->state) {
+	case MAP_RUA_ST_DISCONNECTED:
+	case MAP_RUA_ST_DISRUPTED:
+		return false;
+	default:
+		return true;
+	}
+}
+
+static int map_rua_fsm_timer_cb(struct osmo_fsm_inst *fi)
+{
+	/* Return 1 to terminate FSM instance, 0 to keep running */
+	switch (fi->state) {
+	default:
+		map_rua_fsm_state_chg(MAP_RUA_ST_DISRUPTED);
+		return 0;
+
+	case MAP_RUA_ST_DISCONNECTED:
+	case MAP_RUA_ST_DISRUPTED:
+		return 1;
+	}
+}
+
+/* Dispatch RANAP message to SCCP, if any. */
+static int handle_rx_rua(struct osmo_fsm_inst *fi, struct msgb *ranap_msg)
+{
+	struct hnbgw_context_map *map = fi->priv;
+
+	/* If the FSM instance has already terminated, don't dispatch anything. */
+	if (fi->proc.terminating)
+		return 0;
+
+	if (!msg_has_l2_data(ranap_msg))
+		return 0;
+
+	return hnbgw_ranap_rx_data_ul(map, ranap_msg);
+}
+
+static int forward_ranap_to_rua(struct hnbgw_context_map *map, struct msgb *ranap_msg)
+{
+	int rc;
+
+	if (!msg_has_l2_data(ranap_msg))
+		return 0;
+
+	if (!map->hnb_ctx) {
+		LOGPFSML(map->rua_fi, LOGL_ERROR, "Cannot transmit RUA DirectTransfer: HNB has disconnected\n");
+		return -ENOTCONN;
+	}
+
+	rc = rua_tx_dt(map->hnb_ctx, map->is_ps, map->rua_ctx_id, msgb_l2(ranap_msg), msgb_l2len(ranap_msg));
+	if (rc)
+		LOGPFSML(map->rua_fi, LOGL_ERROR, "Failed to transmit RUA DirectTransfer to HNB\n");
+	return rc;
+}
+
+static void map_rua_init_action(struct osmo_fsm_inst *fi, uint32_t event, void *data)
+{
+	struct msgb *ranap_msg = data;
+
+	switch (event) {
+
+	case MAP_RUA_EV_RX_CONNECT:
+		/* not needed for RAB assignment scanning, but for KPI scanning */
+		handle_rx_rua(fi, ranap_msg);
+		map_rua_fsm_state_chg(MAP_RUA_ST_CONNECTED);
+		return;
+
+	case MAP_RUA_EV_RX_DISCONNECT:
+		/* Unlikely that SCCP is active, but let the SCCP FSM decide about that. */
+		handle_rx_rua(fi, ranap_msg);
+		/* There is a reason to shut down this RUA connection. Super unlikely, we haven't even processed the
+		 * MAP_RUA_EV_RX_CONNECT that created this FSM. Semantically, RUA is not connected, so we can
+		 * directly go to MAP_RUA_ST_DISCONNECTED. */
+		map_rua_fsm_state_chg(MAP_RUA_ST_DISCONNECTED);
+		break;
+
+	case MAP_RUA_EV_CN_DISC:
+	case MAP_RUA_EV_HNB_LINK_LOST:
+		map_rua_fsm_state_chg(MAP_RUA_ST_DISRUPTED);
+		break;
+
+	default:
+		OSMO_ASSERT(false);
+	}
+}
+
+static void map_rua_tx_disconnect(struct osmo_fsm_inst *fi)
+{
+	struct hnbgw_context_map *map = fi->priv;
+	RUA_Cause_t rua_cause;
+
+	if (!map->hnb_ctx || !map->hnb_ctx->conn) {
+		/* HNB already disconnected, nothing to do. */
+		LOGPFSML(fi, LOGL_NOTICE, "HNB vanished, this RUA context cannot disconnect gracefully\n");
+		return;
+	}
+
+	/* Send Disconnect to RUA without RANAP data. */
+	rua_cause = (RUA_Cause_t){
+		.present = RUA_Cause_PR_radioNetwork,
+		.choice.radioNetwork = RUA_CauseRadioNetwork_network_release,
+	};
+	LOGPFSML(fi, LOGL_INFO, "Tx RUA Disconnect\n");
+	if (rua_tx_disc(map->hnb_ctx, map->is_ps, map->rua_ctx_id, &rua_cause, NULL, 0))
+		LOGPFSML(fi, LOGL_ERROR, "Failed to send Disconnect to RUA\n");
+}
+
+static void map_rua_connected_action(struct osmo_fsm_inst *fi, uint32_t event, void *data)
+{
+	struct hnbgw_context_map *map = fi->priv;
+	struct msgb *ranap_msg = data;
+
+	switch (event) {
+
+	case MAP_RUA_EV_RX_DIRECT_TRANSFER:
+		/* received DirectTransfer from RUA, forward to SCCP */
+		handle_rx_rua(fi, ranap_msg);
+		return;
+
+	case MAP_RUA_EV_TX_DIRECT_TRANSFER:
+		/* Someone (usually the SCCP side) wants us to send a RANAP payload to HNB via RUA */
+		forward_ranap_to_rua(map, ranap_msg);
+		return;
+
+	case MAP_RUA_EV_RX_DISCONNECT:
+		/* 3GPP TS 25.468 9.1.5: RUA has disconnected.
+		 * - Under normal conditions (cause=Normal) the RUA Disconnect contains a RANAP Iu-ReleaseComplete.
+		 *   On SCCP, the Iu-ReleaseComplete should still be forwarded as N-Data SCCP Data Form 1),
+		 *   and we will expect the CN to send an SCCP RLSD soon.
+		 * - Under error conditions, cause!=Normal and there's no RANAP message.
+		 *   In that case, we need to tear down the associated SCCP link towards CN,
+		 *   which in turn will tear down the upper layer Iu conn.
+		 */
+		if (msg_has_l2_data(ranap_msg)) {
+			/* Forward any payload to SCCP before Disconnect. */
+			handle_rx_rua(fi, ranap_msg);
+		} else {
+			map->rua_fi_ctx.rua_disconnect_err_condition = true;
+		}
+		map_rua_fsm_state_chg(MAP_RUA_ST_DISCONNECTED);
+		return;
+
+	case MAP_RUA_EV_HNB_LINK_LOST:
+		/* The HNB is gone. Cannot gracefully cleanup the RUA connection, just be gone. */
+		map_rua_fsm_state_chg(MAP_RUA_ST_DISRUPTED);
+		return;
+
+	case MAP_RUA_EV_CN_DISC:
+		/* There is a disruptive reason to shut down this RUA connection, HNB is still there */
+		OSMO_ASSERT(data == NULL);
+		map_rua_tx_disconnect(fi);
+		map_rua_fsm_state_chg(MAP_RUA_ST_DISRUPTED);
+		return;
+
+	default:
+		OSMO_ASSERT(false);
+	}
+}
+
+static void map_rua_free_if_done(struct hnbgw_context_map *map, uint32_t sccp_event, void *ev_data)
+{
+	/* From RUA's POV, we can now free the hnbgw_context_map.
+	 * If SCCP is still active, tell it to disconnect -- in that case the SCCP side will call context_map_free().
+	 * If SCCP is no longer active, free this map. */
+	if (map_sccp_is_active(map))
+		map_sccp_dispatch(map, sccp_event, ev_data);
+	else
+		context_map_free(map);
+}
+
+static void map_rua_disconnected_onenter(struct osmo_fsm_inst *fi, uint32_t prev_state)
+{
+	struct hnbgw_context_map *map = fi->priv;
+	map_rua_free_if_done(map, MAP_SCCP_EV_RAN_DISC, (void *)map->rua_fi_ctx.rua_disconnect_err_condition);
+}
+
+static void map_rua_disconnected_action(struct osmo_fsm_inst *fi, uint32_t event, void *data)
+{
+	struct msgb *ranap_msg;
+
+	switch (event) {
+
+	case MAP_RUA_EV_TX_DIRECT_TRANSFER:
+		/* This can happen if CN is buggy, or in general if there was a race
+		 * condition between us forwarding the release towards CN (SCCP Release
+		 * or RANAP Iu-ReleaseComplete) and CN sendig whatever to us. */
+		ranap_msg = data;
+		if (msg_has_l2_data(ranap_msg)) {
+			LOGPFSML(fi, LOGL_NOTICE, "RUA already disconnected, skip forwarding DL RANAP msg (%u bytes)\n",
+				 msgb_l2len(ranap_msg));
+			LOGPFSML(fi, LOGL_DEBUG, "%s\n", osmo_hexdump(msgb_l2(ranap_msg), msgb_l2len(ranap_msg)));
+		}
+		break;
+
+	case MAP_RUA_EV_CN_DISC:
+	case MAP_RUA_EV_HNB_LINK_LOST:
+		/* Ignore events. */
+		break;
+	}
+}
+
+static void map_rua_disrupted_onenter(struct osmo_fsm_inst *fi, uint32_t prev_state)
+{
+	struct hnbgw_context_map *map = fi->priv;
+	map_rua_free_if_done(map, MAP_SCCP_EV_RAN_LINK_LOST, NULL);
+}
+
+void map_rua_fsm_cleanup(struct osmo_fsm_inst *fi, enum osmo_fsm_term_cause cause)
+{
+	struct hnbgw_context_map *map = fi->priv;
+	map->rua_fi = NULL;
+}
+
+#define S(x) (1 << (x))
+
+static const struct osmo_fsm_state map_rua_fsm_states[] = {
+	[MAP_RUA_ST_INIT] = {
+		.name = "init",
+		.in_event_mask = 0
+			| S(MAP_RUA_EV_RX_CONNECT)
+			| S(MAP_RUA_EV_RX_DISCONNECT)
+			| S(MAP_RUA_EV_CN_DISC)
+			| S(MAP_RUA_EV_HNB_LINK_LOST)
+			,
+		.out_state_mask = 0
+			| S(MAP_RUA_ST_INIT)
+			| S(MAP_RUA_ST_CONNECTED)
+			| S(MAP_RUA_ST_DISCONNECTED)
+			| S(MAP_RUA_ST_DISRUPTED)
+			,
+		.action = map_rua_init_action,
+	},
+	[MAP_RUA_ST_CONNECTED] = {
+		.name = "connected",
+		.in_event_mask = 0
+			| S(MAP_RUA_EV_RX_DIRECT_TRANSFER)
+			| S(MAP_RUA_EV_TX_DIRECT_TRANSFER)
+			| S(MAP_RUA_EV_RX_DISCONNECT)
+			| S(MAP_RUA_EV_CN_DISC)
+			| S(MAP_RUA_EV_HNB_LINK_LOST)
+			,
+		.out_state_mask = 0
+			| S(MAP_RUA_ST_DISCONNECTED)
+			| S(MAP_RUA_ST_DISRUPTED)
+			,
+		.action = map_rua_connected_action,
+	},
+	[MAP_RUA_ST_DISCONNECTED] = {
+		.name = "disconnected",
+		.in_event_mask = 0
+			| S(MAP_RUA_EV_TX_DIRECT_TRANSFER)
+			| S(MAP_RUA_EV_CN_DISC)
+			| S(MAP_RUA_EV_HNB_LINK_LOST)
+			,
+		.onenter = map_rua_disconnected_onenter,
+		.action = map_rua_disconnected_action,
+	},
+	[MAP_RUA_ST_DISRUPTED] = {
+		.name = "disrupted",
+		.in_event_mask = 0
+			| S(MAP_RUA_EV_CN_DISC)
+			| S(MAP_RUA_EV_HNB_LINK_LOST)
+			,
+		.onenter = map_rua_disrupted_onenter,
+		/* same as MAP_RUA_ST_DISCONNECTED: */
+		.action = map_rua_disconnected_action,
+	},
+};
+
+static struct osmo_fsm map_rua_fsm = {
+	.name = "map_rua",
+	.states = map_rua_fsm_states,
+	.num_states = ARRAY_SIZE(map_rua_fsm_states),
+	.log_subsys = DHNB,
+	.event_names = map_rua_fsm_event_names,
+	.timer_cb = map_rua_fsm_timer_cb,
+	.cleanup = map_rua_fsm_cleanup,
+};
+
+static __attribute__((constructor)) void map_rua_fsm_register(void)
+{
+	OSMO_ASSERT(osmo_fsm_register(&map_rua_fsm) == 0);
+}

src/osmo-hnbgw/context_map_sccp.c

@@ -0,0 +1,590 @@
+/* SCCP side FSM of hnbgw_context_map */
+/* (C) 2023 by sysmocom - s.f.m.c. GmbH <info@sysmocom.de>
+ * All Rights Reserved
+ *
+ * SPDX-License-Identifier: AGPL-3.0+
+ *
+ * Author: Neels Hofmeyr
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "config.h"
+
+#include <osmocom/core/utils.h>
+#include <osmocom/core/fsm.h>
+
+#include <osmocom/sigtran/sccp_helpers.h>
+
+#include <osmocom/hnbgw/hnb.h>
+#include <osmocom/hnbgw/hnbgw_cn.h>
+#include <osmocom/hnbgw/context_map.h>
+#include <osmocom/hnbgw/hnbgw_ranap.h>
+#include <osmocom/hnbgw/tdefs.h>
+
+enum map_sccp_fsm_state {
+	MAP_SCCP_ST_INIT,
+	MAP_SCCP_ST_WAIT_CC,
+	MAP_SCCP_ST_CONNECTED,
+	MAP_SCCP_ST_WAIT_RLSD,
+	MAP_SCCP_ST_DISCONNECTED,
+};
+
+static const struct value_string map_sccp_fsm_event_names[] = {
+	OSMO_VALUE_STRING(MAP_SCCP_EV_RX_CONNECTION_CONFIRM),
+	OSMO_VALUE_STRING(MAP_SCCP_EV_RX_DATA_INDICATION),
+	OSMO_VALUE_STRING(MAP_SCCP_EV_TX_DATA_REQUEST),
+	OSMO_VALUE_STRING(MAP_SCCP_EV_RAN_DISC),
+	OSMO_VALUE_STRING(MAP_SCCP_EV_RAN_LINK_LOST),
+	OSMO_VALUE_STRING(MAP_SCCP_EV_RX_RELEASED),
+	OSMO_VALUE_STRING(MAP_SCCP_EV_USER_ABORT),
+	OSMO_VALUE_STRING(MAP_SCCP_EV_CN_LINK_LOST),
+	{}
+};
+
+static struct osmo_fsm map_sccp_fsm;
+
+static const struct osmo_tdef_state_timeout map_sccp_fsm_timeouts[32] = {
+	[MAP_SCCP_ST_INIT] = { .T = -31 },
+	[MAP_SCCP_ST_WAIT_CC] = { .T = -31 },
+	[MAP_SCCP_ST_CONNECTED] = { .T = 0 },
+	[MAP_SCCP_ST_WAIT_RLSD] = { .T = -31 },
+	[MAP_SCCP_ST_DISCONNECTED] = { .T = -31 },
+};
+
+/* Transition to a state, using the T timer defined in map_sccp_fsm_timeouts.
+ * Assumes local variable fi exists. */
+#define map_sccp_fsm_state_chg(state) \
+	OSMO_ASSERT(osmo_tdef_fsm_inst_state_chg(fi, state, \
+						 map_sccp_fsm_timeouts, \
+						 hnbgw_T_defs, \
+						 5) == 0)
+
+void map_sccp_fsm_alloc(struct hnbgw_context_map *map)
+{
+	struct osmo_fsm_inst *fi = osmo_fsm_inst_alloc(&map_sccp_fsm, map, map, LOGL_DEBUG, NULL);
+	OSMO_ASSERT(fi);
+	osmo_fsm_inst_update_id_f_sanitize(fi, '-', "%s-%s-SCCP-%u", hnb_context_name(map->hnb_ctx),
+					   map->cnlink ? map->cnlink->name : (map->is_ps ? "PS" : "CS"),
+					   map->scu_conn_id);
+
+	OSMO_ASSERT(map->sccp_fi == NULL);
+	map->sccp_fi = fi;
+	INIT_LLIST_HEAD(&map->sccp_fi_ctx.wait_cc_tx_msg_list);
+	/* trigger the timeout */
+	map_sccp_fsm_state_chg(MAP_SCCP_ST_INIT);
+}
+
+enum hnbgw_context_map_state map_sccp_get_state(struct hnbgw_context_map *map)
+{
+	if (!map || !map->sccp_fi)
+		return MAP_S_DISCONNECTING;
+	switch (map->sccp_fi->state) {
+	case MAP_SCCP_ST_INIT:
+	case MAP_SCCP_ST_WAIT_CC:
+		return MAP_S_CONNECTING;
+	case MAP_SCCP_ST_CONNECTED:
+		return MAP_S_ACTIVE;
+	default:
+	case MAP_SCCP_ST_WAIT_RLSD:
+	case MAP_SCCP_ST_DISCONNECTED:
+		return MAP_S_DISCONNECTING;
+	}
+}
+
+bool map_sccp_is_active(struct hnbgw_context_map *map)
+{
+	if (!map || !map->sccp_fi)
+		return false;
+	switch (map->sccp_fi->state) {
+	case MAP_SCCP_ST_DISCONNECTED:
+		return false;
+	default:
+		return true;
+	}
+}
+
+static int tx_sccp_cr(struct osmo_fsm_inst *fi, struct msgb *ranap_msg)
+{
+	struct hnbgw_context_map *map = fi->priv;
+
+	if (!map->cnlink) {
+		LOGPFSML(fi, LOGL_ERROR, "Failed to send SCCP Connection Request: no CN link\n");
+		return -1;
+	}
+
+	if (!ranap_msg) {
+		/* prepare a msgb to send an empty N-Connect prim (but this should never happen in practice) */
+		ranap_msg = hnbgw_ranap_msg_alloc("SCCP-CR-empty");
+	}
+
+	CNLINK_CTR_INC(map->cnlink, CNLINK_CTR_SCCP_N_CONNECT_REQ);
+	return hnbgw_sccp_user_tx_connect_req(map->cnlink->hnbgw_sccp_user,
+					      &map->cnlink->remote_addr,
+					      map->scu_conn_id,
+					      ranap_msg);
+}
+
+static int tx_sccp_df1(struct osmo_fsm_inst *fi, struct msgb *ranap_msg)
+{
+	struct hnbgw_context_map *map = fi->priv;
+
+	if (!msg_has_l2_data(ranap_msg))
+		return 0;
+
+	if (!map->cnlink) {
+		LOGPFSML(fi, LOGL_ERROR, "Failed to send SCCP Data Form 1: no CN link\n");
+		return -1;
+	}
+
+	CNLINK_CTR_INC(map->cnlink, CNLINK_CTR_SCCP_N_DATA_REQ);
+	return hnbgw_sccp_user_tx_data_req(map->cnlink->hnbgw_sccp_user,
+					   map->scu_conn_id,
+					   ranap_msg);
+}
+
+static int tx_sccp_rlsd(struct osmo_fsm_inst *fi)
+{
+	struct hnbgw_context_map *map = fi->priv;
+
+	if (!map->cnlink) {
+		LOGPFSML(fi, LOGL_ERROR, "Failed to send SCCP RLSD: no CN link\n");
+		return -1;
+	}
+
+	CNLINK_CTR_INC(map->cnlink, CNLINK_CTR_SCCP_N_DISCONNECT_REQ);
+	return hnbgw_sccp_user_tx_disconnect_req(map->cnlink->hnbgw_sccp_user,
+						 map->scu_conn_id);
+}
+
+static int handle_rx_sccp(struct osmo_fsm_inst *fi, struct msgb *ranap_msg)
+{
+	struct hnbgw_context_map *map = fi->priv;
+
+	/* If the FSM instance has already terminated, don't dispatch anything. */
+	if (fi->proc.terminating)
+		return 0;
+
+	/* When there was no message received along with the received event, then there is nothing to forward to RUA. */
+	if (!msg_has_l2_data(ranap_msg))
+		return 0;
+
+	return hnbgw_ranap_rx_data_dl(map, ranap_msg);
+}
+
+static void wait_cc_tx_msg_list_enqueue(struct hnbgw_context_map *map, struct msgb *ranap_msg)
+{
+	talloc_steal(map, ranap_msg);
+	msgb_enqueue(&map->sccp_fi_ctx.wait_cc_tx_msg_list, ranap_msg);
+}
+
+static struct msgb *wait_cc_tx_msg_list_dequeue(struct hnbgw_context_map *map)
+{
+	struct msgb *ranap_msg = msgb_dequeue(&map->sccp_fi_ctx.wait_cc_tx_msg_list);
+	if (ranap_msg)
+		talloc_steal(OTC_SELECT, ranap_msg);
+	return ranap_msg;
+}
+
+static void map_sccp_init_action(struct osmo_fsm_inst *fi, uint32_t event, void *data)
+{
+	struct msgb *ranap_msg = NULL;
+	struct hnbgw_context_map *map = fi->priv;
+
+	switch (event) {
+
+	case MAP_SCCP_EV_TX_DATA_REQUEST:
+		ranap_msg = data;
+		/* In the INIT state, the first MAP_SCCP_EV_TX_DATA_REQUEST will be the RANAP message received from the
+		 * RUA Connect message. Send the SCCP CR and transition to WAIT_CC. */
+		if (tx_sccp_cr(fi, ranap_msg) == 0)
+			map_sccp_fsm_state_chg(MAP_SCCP_ST_WAIT_CC);
+		return;
+
+	case MAP_SCCP_EV_RAN_LINK_LOST:
+	case MAP_SCCP_EV_USER_ABORT:
+	case MAP_SCCP_EV_CN_LINK_LOST:
+		map_sccp_fsm_state_chg(MAP_SCCP_ST_DISCONNECTED);
+		return;
+
+	case MAP_SCCP_EV_RAN_DISC:
+		/* bool rua_disconnect_err_condition = !!data; */
+		/* 3GPP TS 25.468 9.1.5: RUA has disconnected.
+		 * In this state we didn't send an SCCP CR yet, so nothing to be torn down on CN side. */
+		map_sccp_fsm_state_chg(MAP_SCCP_ST_DISCONNECTED);
+		return;
+
+	case MAP_SCCP_EV_RX_RELEASED:
+		/* SCCP RLSD received from CN. This will never happen since we haven't even asked for a connection, but
+		 * for completeness: */
+		CNLINK_CTR_INC(map->cnlink, CNLINK_CTR_SCCP_RLSD_CN_ORIGIN);
+		map_sccp_fsm_state_chg(MAP_SCCP_ST_DISCONNECTED);
+		return;
+
+	default:
+		OSMO_ASSERT(false);
+	}
+}
+
+static void map_sccp_wait_cc_action(struct osmo_fsm_inst *fi, uint32_t event, void *data)
+{
+	struct hnbgw_context_map *map = fi->priv;
+	struct msgb *ranap_msg = NULL;
+
+	switch (event) {
+
+	case MAP_SCCP_EV_RX_CONNECTION_CONFIRM:
+		ranap_msg = data;
+		map_sccp_fsm_state_chg(MAP_SCCP_ST_CONNECTED);
+		/* Usually doesn't but if the SCCP CC contained data, forward it to RUA */
+		handle_rx_sccp(fi, ranap_msg);
+		return;
+
+	case MAP_SCCP_EV_TX_DATA_REQUEST:
+		ranap_msg = data;
+		LOGPFSML(fi, LOGL_INFO, "Caching RANAP msg from RUA while waiting for SCCP CC\n");
+		wait_cc_tx_msg_list_enqueue(map, ranap_msg);
+		return;
+
+	case MAP_SCCP_EV_RAN_LINK_LOST:
+	case MAP_SCCP_EV_USER_ABORT:
+	case MAP_SCCP_EV_CN_LINK_LOST:
+		map->please_disconnect = true;
+		return;
+
+	case MAP_SCCP_EV_RAN_DISC:
+		/* bool rua_disconnect_err_condition = !!data; */
+		/* 3GPP TS 25.468 9.1.5: RUA has disconnected.
+		 * In this state we didn't send an SCCP CR yet, so nothing to be torn down on CN side. */
+		map->please_disconnect = true;
+		return;
+
+	case MAP_SCCP_EV_RX_RELEASED:
+		ranap_msg = data;
+		/* SCCP RLSD received from CN. This will never happen since we haven't even received a Connection
+		 * Confirmed, but for completeness: */
+		CNLINK_CTR_INC(map->cnlink, CNLINK_CTR_SCCP_RLSD_CN_ORIGIN);
+		handle_rx_sccp(fi, ranap_msg);
+		map_sccp_fsm_state_chg(MAP_SCCP_ST_DISCONNECTED);
+		return;
+
+	default:
+		OSMO_ASSERT(false);
+	}
+}
+
+static void map_sccp_connected_onenter(struct osmo_fsm_inst *fi, uint32_t prev_state)
+{
+	struct hnbgw_context_map *map = fi->priv;
+	struct msgb *ranap_msg;
+
+	/* Now that SCCP conn is confirmed, forward pending msgs received from RUA side: */
+	while ((ranap_msg = wait_cc_tx_msg_list_dequeue(map)))
+		tx_sccp_df1(fi, ranap_msg);
+
+	if (map->please_disconnect) {
+		/* SCCP has already been asked to disconnect, so disconnect now that the
+		 * CC has been received. Send RLSD to SCCP (without RANAP data) */
+		tx_sccp_rlsd(fi);
+		map_sccp_fsm_state_chg(MAP_SCCP_ST_DISCONNECTED);
+	}
+}
+
+static void map_sccp_connected_action(struct osmo_fsm_inst *fi, uint32_t event, void *data)
+{
+	struct hnbgw_context_map *map = fi->priv;
+	struct msgb *ranap_msg = NULL;
+	bool rua_disconnect_err_condition;
+
+	switch (event) {
+
+	case MAP_SCCP_EV_RX_DATA_INDICATION:
+		ranap_msg = data;
+		/* forward RANAP from SCCP to RUA */
+		handle_rx_sccp(fi, ranap_msg);
+		return;
+
+	case MAP_SCCP_EV_TX_DATA_REQUEST:
+		ranap_msg = data;
+		/* Someone (usually the RUA side) wants us to send a RANAP payload to CN via SCCP */
+		tx_sccp_df1(fi, ranap_msg);
+		return;
+
+	case MAP_SCCP_EV_RAN_DISC:
+		rua_disconnect_err_condition = !!data;
+		/* 3GPP TS 25.468 9.1.5: RUA has disconnected.
+		 * - Under normal conditions (cause=Normal) the RUA Disconnect
+		 *   contained a RANAP Iu-ReleaseComplete which we already
+		 *   handled here through MAP_SCCP_EV_TX_DATA_REQUEST.
+		 *   On SCCP, We will expect the CN to send an SCCP RLSD soon.
+		 * - Under error conditions, cause!=Normal and there was no RANAP message.
+		 *   In that case, we need to tear down the associated SCCP link towards CN,
+		 *   which in turn will tear down the upper layer Iu conn.
+		 */
+		if (rua_disconnect_err_condition) {
+			tx_sccp_rlsd(fi);
+			map_sccp_fsm_state_chg(MAP_SCCP_ST_DISCONNECTED);
+		} else {
+			map_sccp_fsm_state_chg(MAP_SCCP_ST_WAIT_RLSD);
+		}
+		return;
+
+	case MAP_SCCP_EV_RAN_LINK_LOST:
+		/* RUA has disconnected ungracefully, so there is no Iu Release that told the CN to disconnect.
+		 * Disconnect on the SCCP layer, ungracefully. */
+	case MAP_SCCP_EV_USER_ABORT:
+		/* The user is asking for disconnection, so there is no Iu Release in progress. Disconnect now. */
+	case MAP_SCCP_EV_CN_LINK_LOST:
+		/* The CN peer has sent a RANAP RESET, so the old link that this map ran on is lost */
+		tx_sccp_rlsd(fi);
+		map_sccp_fsm_state_chg(MAP_SCCP_ST_DISCONNECTED);
+		return;
+
+	case MAP_SCCP_EV_RX_RELEASED:
+		ranap_msg = data;
+		/* The CN sends an N-Disconnect (SCCP Released). */
+		CNLINK_CTR_INC(map->cnlink, CNLINK_CTR_SCCP_RLSD_CN_ORIGIN);
+		handle_rx_sccp(fi, ranap_msg);
+		map_sccp_fsm_state_chg(MAP_SCCP_ST_DISCONNECTED);
+		return;
+
+	case MAP_SCCP_EV_RX_CONNECTION_CONFIRM:
+		ranap_msg = data;
+		/* Already connected. Unusual, but if there is data just forward it. */
+		LOGPFSML(fi, LOGL_ERROR, "Already connected, but received SCCP CC again\n");
+		handle_rx_sccp(fi, ranap_msg);
+		return;
+
+	default:
+		OSMO_ASSERT(false);
+	}
+}
+
+static void map_sccp_wait_rlsd_onenter(struct osmo_fsm_inst *fi, uint32_t prev_state)
+{
+	struct hnbgw_context_map *map = fi->priv;
+	/* For sanity, always tell RUA to disconnect, if it hasn't done so. */
+	if (map_rua_is_active(map))
+		map_rua_dispatch(map, MAP_RUA_EV_CN_DISC, NULL);
+}
+
+static void map_sccp_wait_rlsd_action(struct osmo_fsm_inst *fi, uint32_t event, void *data)
+{
+	struct msgb *ranap_msg = NULL;
+
+	switch (event) {
+
+	case MAP_SCCP_EV_RX_RELEASED:
+		ranap_msg = data;
+		/* The CN sends the expected SCCP RLSD.
+		 * Usually there is no data, but if there is just forward it.
+		 * Usually RUA is already disconnected, but let the RUA FSM decide about that. */
+		handle_rx_sccp(fi, ranap_msg);
+		map_sccp_fsm_state_chg(MAP_SCCP_ST_DISCONNECTED);
+		return;
+
+	case MAP_SCCP_EV_RX_DATA_INDICATION:
+		ranap_msg = data;
+		/* RUA is probably already disconnected, but let the RUA FSM decide about that. */
+		handle_rx_sccp(fi, ranap_msg);
+		return;
+
+	case MAP_SCCP_EV_TX_DATA_REQUEST:
+		ranap_msg = data;
+		/* Normally, RUA would already disconnected, but since SCCP is officially still connected, we can still
+		 * forward messages there. Already waiting for CN to send the SCCP RLSD. If there is a message, forward
+		 * it, and just continue to time out on the SCCP RLSD. */
+		tx_sccp_df1(fi, ranap_msg);
+		return;
+
+	case MAP_SCCP_EV_RX_CONNECTION_CONFIRM:
+		ranap_msg = data;
+		/* Already connected. Unusual, but if there is data just forward it. */
+		LOGPFSML(fi, LOGL_ERROR, "Already connected, but received SCCP CC\n");
+		handle_rx_sccp(fi, ranap_msg);
+		return;
+
+	case MAP_SCCP_EV_RAN_LINK_LOST:
+	case MAP_SCCP_EV_USER_ABORT:
+	case MAP_SCCP_EV_CN_LINK_LOST:
+	case MAP_SCCP_EV_RAN_DISC:
+		/* Stop waiting for RLSD, send RLSD now. */
+		tx_sccp_rlsd(fi);
+		map_sccp_fsm_state_chg(MAP_SCCP_ST_DISCONNECTED);
+		return;
+
+	default:
+		OSMO_ASSERT(false);
+	}
+}
+
+static void map_sccp_disconnected_onenter(struct osmo_fsm_inst *fi, uint32_t prev_state)
+{
+	struct hnbgw_context_map *map = fi->priv;
+	/* From SCCP's POV, we can now free the hnbgw_context_map.
+	 * If RUA is still active, tell it to disconnect -- in that case the RUA side will call context_map_free().
+	 * If RUA is no longer active, free this map. */
+	if (map_rua_is_active(map))
+		map_rua_dispatch(map, MAP_RUA_EV_CN_DISC, NULL);
+	else
+		context_map_free(map);
+}
+
+static void map_sccp_disconnected_action(struct osmo_fsm_inst *fi, uint32_t event, void *data)
+{
+	struct msgb *ranap_msg = data;
+
+	if (msg_has_l2_data(ranap_msg))
+		LOGPFSML(fi, LOGL_ERROR, "SCCP not connected, cannot dispatch RANAP message\n");
+}
+
+static int map_sccp_fsm_timer_cb(struct osmo_fsm_inst *fi)
+{
+	struct hnbgw_context_map *map = fi->priv;
+
+	/* Return 1 to terminate FSM instance, 0 to keep running */
+	switch (fi->state) {
+	case MAP_SCCP_ST_INIT:
+		/* cannot sent SCCP RLSD, because we haven't set up an SCCP link */
+		map_sccp_fsm_state_chg(MAP_SCCP_ST_DISCONNECTED);
+		return 0;
+
+	case MAP_SCCP_ST_WAIT_CC:
+		/* send N-DISCONNECT. libosmo-sigtran/sccp_scoc.c will do the SCCP connection cleanup, like waiting a
+		 * bit whether the SCCP CC might still arrive, and cleanup the conn if not. */
+	case MAP_SCCP_ST_CONNECTED:
+	case MAP_SCCP_ST_WAIT_RLSD:
+		/* send SCCP RLSD. libosmo-sigtran/sccp_scoc.c will do the SCCP connection cleanup.
+		 * (It will repeatedly send SCCP RLSD until the peer responded with SCCP RLC, or until the
+		 * sccp_connection->t_int timer expires, and the sccp_connection is freed.) */
+		if (map->cnlink)
+			tx_sccp_rlsd(fi);
+		map_sccp_fsm_state_chg(MAP_SCCP_ST_DISCONNECTED);
+		return 0;
+
+	default:
+	case MAP_SCCP_ST_DISCONNECTED:
+		return 1;
+	}
+}
+
+void map_sccp_fsm_cleanup(struct osmo_fsm_inst *fi, enum osmo_fsm_term_cause cause)
+{
+	struct hnbgw_context_map *map = fi->priv;
+	map->sccp_fi = NULL;
+	msgb_queue_free(&map->sccp_fi_ctx.wait_cc_tx_msg_list);
+}
+
+#define S(x)    (1 << (x))
+
+static const struct osmo_fsm_state map_sccp_fsm_states[] = {
+	[MAP_SCCP_ST_INIT] = {
+		.name = "init",
+		.in_event_mask = 0
+			| S(MAP_SCCP_EV_TX_DATA_REQUEST)
+			| S(MAP_SCCP_EV_RAN_DISC)
+			| S(MAP_SCCP_EV_RAN_LINK_LOST)
+			| S(MAP_SCCP_EV_RX_RELEASED)
+			| S(MAP_SCCP_EV_USER_ABORT)
+			| S(MAP_SCCP_EV_CN_LINK_LOST)
+			,
+		.out_state_mask = 0
+			| S(MAP_SCCP_ST_INIT)
+			| S(MAP_SCCP_ST_WAIT_CC)
+			| S(MAP_SCCP_ST_DISCONNECTED)
+			,
+		.action = map_sccp_init_action,
+	},
+	[MAP_SCCP_ST_WAIT_CC] = {
+		.name = "wait_cc",
+		.in_event_mask = 0
+			| S(MAP_SCCP_EV_RX_CONNECTION_CONFIRM)
+			| S(MAP_SCCP_EV_TX_DATA_REQUEST)
+			| S(MAP_SCCP_EV_RAN_DISC)
+			| S(MAP_SCCP_EV_RAN_LINK_LOST)
+			| S(MAP_SCCP_EV_RX_RELEASED)
+			| S(MAP_SCCP_EV_USER_ABORT)
+			| S(MAP_SCCP_EV_CN_LINK_LOST)
+			,
+		.out_state_mask = 0
+			| S(MAP_SCCP_ST_CONNECTED)
+			| S(MAP_SCCP_ST_DISCONNECTED)
+			,
+		.action = map_sccp_wait_cc_action,
+	},
+	[MAP_SCCP_ST_CONNECTED] = {
+		.name = "connected",
+		.in_event_mask = 0
+			| S(MAP_SCCP_EV_RX_DATA_INDICATION)
+			| S(MAP_SCCP_EV_TX_DATA_REQUEST)
+			| S(MAP_SCCP_EV_RAN_DISC)
+			| S(MAP_SCCP_EV_RAN_LINK_LOST)
+			| S(MAP_SCCP_EV_RX_RELEASED)
+			| S(MAP_SCCP_EV_RX_CONNECTION_CONFIRM)
+			| S(MAP_SCCP_EV_USER_ABORT)
+			| S(MAP_SCCP_EV_CN_LINK_LOST)
+			,
+		.out_state_mask = 0
+			| S(MAP_SCCP_ST_WAIT_RLSD)
+			| S(MAP_SCCP_ST_DISCONNECTED)
+			,
+		.onenter = map_sccp_connected_onenter,
+		.action = map_sccp_connected_action,
+	},
+	[MAP_SCCP_ST_WAIT_RLSD] = {
+		.name = "wait_rlsd",
+		.in_event_mask = 0
+			| S(MAP_SCCP_EV_RX_RELEASED)
+			| S(MAP_SCCP_EV_RX_DATA_INDICATION)
+			| S(MAP_SCCP_EV_TX_DATA_REQUEST)
+			| S(MAP_SCCP_EV_RAN_DISC)
+			| S(MAP_SCCP_EV_RAN_LINK_LOST)
+			| S(MAP_SCCP_EV_RX_CONNECTION_CONFIRM)
+			| S(MAP_SCCP_EV_USER_ABORT)
+			| S(MAP_SCCP_EV_CN_LINK_LOST)
+			,
+		.out_state_mask = 0
+			| S(MAP_SCCP_ST_DISCONNECTED)
+			,
+		.onenter = map_sccp_wait_rlsd_onenter,
+		.action = map_sccp_wait_rlsd_action,
+	},
+	[MAP_SCCP_ST_DISCONNECTED] = {
+		.name = "disconnected",
+		.in_event_mask = 0
+			| S(MAP_SCCP_EV_TX_DATA_REQUEST)
+			| S(MAP_SCCP_EV_RAN_DISC)
+			| S(MAP_SCCP_EV_RAN_LINK_LOST)
+			| S(MAP_SCCP_EV_USER_ABORT)
+			| S(MAP_SCCP_EV_CN_LINK_LOST)
+			,
+		.onenter = map_sccp_disconnected_onenter,
+		.action = map_sccp_disconnected_action,
+	},
+};
+
+static struct osmo_fsm map_sccp_fsm = {
+	.name = "map_sccp",
+	.states = map_sccp_fsm_states,
+	.num_states = ARRAY_SIZE(map_sccp_fsm_states),
+	.log_subsys = DCN,
+	.event_names = map_sccp_fsm_event_names,
+	.timer_cb = map_sccp_fsm_timer_cb,
+	.cleanup = map_sccp_fsm_cleanup,
+};
+
+static __attribute__((constructor)) void map_sccp_fsm_register(void)
+{
+	OSMO_ASSERT(osmo_fsm_register(&map_sccp_fsm) == 0);
+}

src/osmo-hnbgw/hnb.c

@@ -0,0 +1,401 @@
+/* HNB related code */
+
+/* (C) 2015,2024 by Harald Welte <laforge@gnumonks.org>
+ * (C) 2016-2025 by sysmocom s.f.m.c. GmbH <info@sysmocom.de>
+ * All Rights Reserved
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include "config.h"
+
+#include <inttypes.h>
+
+#include <netinet/in.h>
+#include <netinet/sctp.h>
+
+#include <osmocom/core/stats.h>
+#include <osmocom/core/rate_ctr.h>
+#include <osmocom/core/stat_item.h>
+
+#include <osmocom/gsm/gsm23236.h>
+
+#include <osmocom/netif/stream.h>
+
+#include <osmocom/hnbgw/umts_cell_id.h>
+#include <osmocom/hnbgw/hnb.h>
+#include <osmocom/hnbgw/hnb_persistent.h>
+#include <osmocom/hnbgw/hnbgw.h>
+#include <osmocom/hnbgw/hnbgw_hnbap.h>
+#include <osmocom/hnbgw/hnbgw_rua.h>
+#include <osmocom/hnbgw/tdefs.h>
+#include <osmocom/hnbgw/context_map.h>
+#include <osmocom/hnbgw/mgw_fsm.h>
+
+/* update the active RAB duration rate_ctr for given HNB */
+void hnb_store_rab_durations(struct hnb_context *hnb)
+{
+	struct hnbgw_context_map *map;
+	struct timespec now;
+	uint64_t elapsed_cs_rab_ms = 0;
+
+	osmo_clock_gettime(CLOCK_MONOTONIC, &now);
+
+	/* iterate over all context_maps (subscribers) */
+	llist_for_each_entry(map, &hnb->map_list, hnb_list) {
+		/* skip any PS maps, we care about CS RABs only here */
+		if (map->is_ps)
+			continue;
+		elapsed_cs_rab_ms += mgw_fsm_get_elapsed_ms(map, &now);
+	}
+
+	/* Export to rate countes. */
+	rate_ctr_add(HNBP_CTR(hnb->persistent, HNB_CTR_RAB_ACTIVE_MILLISECONDS_TOTAL), elapsed_cs_rab_ms);
+}
+
+/***********************************************************************
+ * HNB Context
+ ***********************************************************************/
+
+/* look-up HNB context by id. Used from CTRL */
+static struct hnb_context *hnb_context_by_id(uint32_t cid)
+{
+	struct hnb_context *hnb;
+
+	llist_for_each_entry(hnb, &g_hnbgw->hnb_list, list) {
+		if (hnb->id.cid == cid)
+			return hnb;
+	}
+
+	return NULL;
+}
+
+/* look-up HNB context by identity_info. Used from VTY */
+struct hnb_context *hnb_context_by_identity_info(const char *identity_info)
+{
+	struct hnb_context *hnb;
+
+	llist_for_each_entry(hnb, &g_hnbgw->hnb_list, list) {
+		if (strcmp(identity_info, hnb->identity_info) == 0)
+			return hnb;
+	}
+
+	return NULL;
+}
+
+static int hnb_read_cb(struct osmo_stream_srv *conn);
+static int hnb_closed_cb(struct osmo_stream_srv *conn);
+
+static struct hnb_context *hnb_context_alloc(struct osmo_stream_srv_link *link, int new_fd)
+{
+	struct hnb_context *ctx;
+
+	ctx = talloc_zero(g_hnbgw, struct hnb_context);
+	if (!ctx)
+		return NULL;
+	INIT_LLIST_HEAD(&ctx->map_list);
+
+	ctx->conn = osmo_stream_srv_create(g_hnbgw, link, new_fd, hnb_read_cb, hnb_closed_cb, ctx);
+	if (!ctx->conn) {
+		LOGP(DMAIN, LOGL_INFO, "error while creating connection\n");
+		talloc_free(ctx);
+		return NULL;
+	}
+
+	llist_add_tail(&ctx->list, &g_hnbgw->hnb_list);
+	return ctx;
+}
+
+const char *hnb_context_name(struct hnb_context *ctx)
+{
+	char *result;
+	if (!ctx)
+		return "NULL";
+
+	if (ctx->conn) {
+		char hostbuf_r[INET6_ADDRSTRLEN];
+		char portbuf_r[6];
+		int fd = osmo_stream_srv_get_ofd(ctx->conn)->fd;
+
+		/* get remote addr */
+		if (osmo_sock_get_ip_and_port(fd, hostbuf_r, sizeof(hostbuf_r), portbuf_r, sizeof(portbuf_r), false) == 0)
+			result = talloc_asprintf(OTC_SELECT, "%s:%s", hostbuf_r, portbuf_r);
+		else
+			result = "?";
+	} else {
+		result = "disconnected";
+	}
+
+	if (g_hnbgw->config.log_prefix_hnb_id)
+		result = talloc_asprintf(OTC_SELECT, "%s %s", result, ctx->identity_info);
+	else
+		result = talloc_asprintf(OTC_SELECT, "%s %s", result, umts_cell_id_to_str(&ctx->id));
+	return result;
+}
+
+void hnb_context_release_ue_state(struct hnb_context *ctx)
+{
+	struct hnbgw_context_map *map, *map2;
+
+	/* deactivate all context maps */
+	llist_for_each_entry_safe(map, map2, &ctx->map_list, hnb_list) {
+		context_map_hnb_released(map);
+		/* hnbgw_context_map will remove itself from lists when it is ready. */
+	}
+}
+
+void hnb_context_release(struct hnb_context *ctx)
+{
+	struct hnbgw_context_map *map;
+
+	LOGHNB(ctx, DMAIN, LOGL_INFO, "Releasing HNB context\n");
+
+	if (ctx->persistent) {
+		struct timespec tp;
+		int rc;
+		rc = osmo_clock_gettime(CLOCK_MONOTONIC, &tp);
+		ctx->persistent->updowntime = (rc < 0) ? 0 : tp.tv_sec;
+	}
+
+	/* remove from the list of HNB contexts */
+	llist_del(&ctx->list);
+
+	hnb_context_release_ue_state(ctx);
+
+	if (ctx->conn) { /* we own a conn, we must free it: */
+		LOGHNB(ctx, DMAIN, LOGL_INFO, "Closing HNB SCTP connection %s\n",
+		     osmo_sock_get_name2(osmo_stream_srv_get_ofd(ctx->conn)->fd));
+		/* Avoid our closed_cb calling hnb_context_release() again: */
+		osmo_stream_srv_set_data(ctx->conn, NULL);
+		osmo_stream_srv_destroy(ctx->conn);
+	} /* else: we are called from closed_cb, so conn is being freed separately */
+
+	/* hnbgw_context_map are still listed in ctx->map_list, but we are freeing ctx. Remove all entries from the
+	 * list, but keep the hnbgw_context_map around for graceful release. They are also listed under
+	 * hnbgw_cnlink->map_list, and will remove themselves when ready. */
+	while ((map = llist_first_entry_or_null(&ctx->map_list, struct hnbgw_context_map, hnb_list))) {
+		llist_del(&map->hnb_list);
+		map->hnb_ctx = NULL;
+	}
+
+	/* remove back reference from hnb_persistent to context */
+	if (ctx->persistent)
+		hnb_persistent_deregistered(ctx->persistent);
+
+	talloc_free(ctx);
+}
+
+unsigned long long hnb_get_updowntime(const struct hnb_context *ctx)
+{
+	if (!ctx->persistent)
+		return 0;
+	return hnbp_get_updowntime(ctx->persistent);
+}
+
+/***********************************************************************
+ * SCTP Socket / stream handling
+ ***********************************************************************/
+
+static int hnb_read_cb(struct osmo_stream_srv *conn)
+{
+	struct hnb_context *hnb = osmo_stream_srv_get_data(conn);
+	struct osmo_fd *ofd = osmo_stream_srv_get_ofd(conn);
+	struct msgb *msg = msgb_alloc(IUH_MSGB_SIZE, "Iuh rx");
+	int rc;
+
+	if (!msg)
+		return -ENOMEM;
+
+	OSMO_ASSERT(hnb);
+	/* we store a reference to the HomeNodeB in the msg->dest for the
+	 * benefit of various downstream processing functions */
+	msg->dst = hnb;
+
+	rc = osmo_stream_srv_recv(conn, msg);
+	/* Notification received */
+	if (msgb_sctp_msg_flags(msg) & OSMO_STREAM_SCTP_MSG_FLAGS_NOTIFICATION) {
+		union sctp_notification *notif = (union sctp_notification *)msgb_data(msg);
+		rc = 0;
+		switch (notif->sn_header.sn_type) {
+		case SCTP_ASSOC_CHANGE:
+			switch (notif->sn_assoc_change.sac_state) {
+			case SCTP_COMM_LOST:
+				LOGHNB(hnb, DMAIN, LOGL_NOTICE,
+				       "sctp_recvmsg(%s) = SCTP_COMM_LOST, closing conn\n",
+				       osmo_sock_get_name2(ofd->fd));
+				osmo_stream_srv_destroy(conn);
+				rc = -EBADF;
+				break;
+			case SCTP_RESTART:
+				LOGHNB(hnb, DMAIN, LOGL_NOTICE, "HNB SCTP conn RESTARTed, marking as HNBAP-unregistered\n");
+				hnb->hnb_registered = false;
+				hnb_context_release_ue_state(hnb);
+				/* The tx queue may be quite full after an SCTP RESTART: (SYS#6113)
+				 * The link may have been flaky (a possible reason for the peer restarting the conn) and
+				 * hence the kernel socket Tx queue may be full (no ACKs coming back) and our own userspace
+				 * queue may contain plenty of oldish messages to be sent. Since the HNB will re-register after
+				 * this, we simply drop all those old messages: */
+				osmo_stream_srv_clear_tx_queue(conn);
+				break;
+			}
+			break;
+		case SCTP_SHUTDOWN_EVENT:
+			LOGHNB(hnb, DMAIN, LOGL_NOTICE,
+			       "sctp_recvmsg(%s) = SCTP_SHUTDOWN_EVENT, closing conn\n",
+			       osmo_sock_get_name2(ofd->fd));
+			osmo_stream_srv_destroy(conn);
+			rc = -EBADF;
+			break;
+		}
+		goto out;
+	} else if (rc == -EAGAIN) {
+		/* Older versions of osmo_stream_srv_recv() not supporting
+		 * msgb_sctp_msg_flags() may still return -EAGAIN when an sctp
+		 * notification is received. */
+		rc = 0;
+		goto out;
+	} else if (rc < 0) {
+		LOGHNB(hnb, DMAIN, LOGL_ERROR, "Error during sctp_recvmsg(%s)\n",
+		       osmo_sock_get_name2(ofd->fd));
+		osmo_stream_srv_destroy(conn);
+		rc = -EBADF;
+		goto out;
+	} else if (rc == 0) {
+		LOGHNB(hnb, DMAIN, LOGL_NOTICE, "Connection closed sctp_recvmsg(%s) = 0\n",
+		       osmo_sock_get_name2(ofd->fd));
+		osmo_stream_srv_destroy(conn);
+		rc = -EBADF;
+		goto out;
+	} else {
+		msgb_put(msg, rc);
+	}
+
+	switch (msgb_sctp_ppid(msg)) {
+	case IUH_PPI_HNBAP:
+		hnb->hnbap_stream = msgb_sctp_stream(msg);
+		rc = hnbgw_hnbap_rx(hnb, msg);
+		break;
+	case IUH_PPI_RUA:
+		if (!hnb->hnb_registered) {
+			LOGHNB(hnb, DMAIN, LOGL_NOTICE, "Discarding RUA as HNB is not registered\n");
+			goto out;
+		}
+		hnb->rua_stream = msgb_sctp_stream(msg);
+		rc = hnbgw_rua_rx(hnb, msg);
+		break;
+	case IUH_PPI_SABP:
+	case IUH_PPI_RNA:
+	case IUH_PPI_PUA:
+		LOGHNB(hnb, DMAIN, LOGL_ERROR, "Unimplemented SCTP PPID=%lu received\n", msgb_sctp_ppid(msg));
+		rc = 0;
+		break;
+	default:
+		LOGHNB(hnb, DMAIN, LOGL_ERROR, "Unknown SCTP PPID=%lu received\n", msgb_sctp_ppid(msg));
+		rc = 0;
+		break;
+	}
+
+out:
+	msgb_free(msg);
+	return rc;
+}
+
+static int hnb_closed_cb(struct osmo_stream_srv *conn)
+{
+	struct hnb_context *hnb = osmo_stream_srv_get_data(conn);
+	if (!hnb)
+		return 0; /* hnb_context is being freed, nothing do be done */
+
+	/* hnb: conn became broken, let's release the associated hnb.
+	 * conn object is being freed after closed_cb(), so unassign it from hnb
+	 * if available to avoid it freeing it again: */
+	hnb->conn = NULL;
+	hnb_context_release(hnb);
+
+	return 0;
+}
+
+/*! call-back when the listen FD has something to read */
+int hnbgw_rua_accept_cb(struct osmo_stream_srv_link *srv, int fd)
+{
+	struct hnb_context *ctx;
+
+	LOGP(DMAIN, LOGL_INFO, "New HNB SCTP connection %s\n",
+	     osmo_sock_get_name2(fd));
+
+	ctx = hnb_context_alloc(srv, fd);
+	if (!ctx)
+		return -ENOMEM;
+
+	return 0;
+}
+
+CTRL_CMD_DEFINE_RO(hnb_info, "info");
+static int get_hnb_info(struct ctrl_cmd *cmd, void *data)
+{
+	struct hnb_context *hnb = data;
+
+	cmd->reply = talloc_strdup(cmd, hnb->identity_info);
+
+	return CTRL_CMD_REPLY;
+}
+
+CTRL_CMD_DEFINE_RO(hnbs, "num-hnb");
+static int get_hnbs(struct ctrl_cmd *cmd, void *data)
+{
+	cmd->reply = talloc_asprintf(cmd, "%u", llist_count(&g_hnbgw->hnb_list));
+
+	return CTRL_CMD_REPLY;
+}
+
+int hnb_ctrl_cmds_install(void)
+{
+	int rc = 0;
+
+	rc |= ctrl_cmd_install(CTRL_NODE_ROOT, &cmd_hnbs);
+	rc |= ctrl_cmd_install(CTRL_NODE_HNB, &cmd_hnb_info);
+
+	return rc;
+}
+
+int hnb_ctrl_node_lookup(void *data, vector vline, int *node_type, void **node_data, int *i)
+{
+	const char *token = vector_slot(vline, *i);
+	struct hnb_context *hnb;
+	long num;
+
+	switch (*node_type) {
+	case CTRL_NODE_ROOT:
+		if (strcmp(token, "hnb") != 0)
+			return 0;
+
+		(*i)++;
+
+		if (!ctrl_parse_get_num(vline, *i, &num))
+			return -ERANGE;
+
+		hnb = hnb_context_by_id(num);
+		if (!hnb)
+			return -ENODEV;
+
+		*node_data = hnb;
+		*node_type = CTRL_NODE_HNB;
+		break;
+	default:
+		return 0;
+	}
+
+	return 1;
+}

src/osmo-hnbgw/hnb_persistent.c

@@ -0,0 +1,403 @@
+/* HNB persistent related code */
+
+/* (C) 2015,2024 by Harald Welte <laforge@gnumonks.org>
+ * (C) 2016-2025 by sysmocom s.f.m.c. GmbH <info@sysmocom.de>
+ * All Rights Reserved
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include "config.h"
+
+#include <inttypes.h>
+
+#include <netinet/in.h>
+#include <netinet/sctp.h>
+
+#include <osmocom/core/stats.h>
+#include <osmocom/core/rate_ctr.h>
+#include <osmocom/core/stat_item.h>
+#include <osmocom/core/jhash.h>
+
+#include <osmocom/gsm/gsm23236.h>
+
+#include <osmocom/netif/stream.h>
+
+#include <osmocom/hnbgw/hnb.h>
+#include <osmocom/hnbgw/hnb_persistent.h>
+#include <osmocom/hnbgw/hnbgw.h>
+#include <osmocom/hnbgw/tdefs.h>
+
+/***********************************************************************
+ * HNB Persistent Data
+ ***********************************************************************/
+
+const struct rate_ctr_desc hnb_ctr_description[] = {
+	[HNB_CTR_IUH_ESTABLISHED] = {
+		"iuh:established", "Number of times Iuh link was established" },
+
+	[HNB_CTR_RANAP_PS_ERR_IND_UL] = {
+		"ranap:ps:error_ind:ul", "Received ERROR Indications in Uplink (PS Domain)" },
+	[HNB_CTR_RANAP_CS_ERR_IND_UL] = {
+		"ranap:cs:error_ind:ul", "Received ERROR Indications in Uplink (PS Domain)" },
+
+	[HNB_CTR_RANAP_PS_RESET_REQ_UL] = {
+		"ranap:ps:reset_req:ul", "Received RESET Requests in Uplink (PS Domain)" },
+	[HNB_CTR_RANAP_CS_RESET_REQ_UL] = {
+		"ranap:cs:reset_req:ul", "Received RESET Requests in Uplink (CS Domain)" },
+
+
+	[HNB_CTR_RANAP_PS_RAB_ACT_REQ] = {
+		"ranap:ps:rab_act:req", "PS RAB Activations requested" },
+	[HNB_CTR_RANAP_CS_RAB_ACT_REQ] = {
+		"ranap:cs:rab_act:req", "CS RAB Activations requested" },
+	[HNB_CTR_RANAP_PS_RAB_ACT_REQ_UNEXP] = {
+		"ranap:ps:rab_act:req_unexp", "PS RAB Activations requested in unexpected state" },
+	[HNB_CTR_RANAP_CS_RAB_ACT_REQ_UNEXP] = {
+		"ranap:cs:rab_act:req_unexp", "CS RAB Activations requested in unexpected state" },
+
+	[HNB_CTR_RANAP_PS_RAB_ACT_CNF] = {
+		"ranap:ps:rab_act:cnf", "PS RAB Activations confirmed" },
+	[HNB_CTR_RANAP_CS_RAB_ACT_CNF] = {
+		"ranap:cs:rab_act:cnf", "CS RAB Activations confirmed" },
+	[HNB_CTR_RANAP_PS_RAB_ACT_CNF_UNEXP] = {
+		"ranap:ps:rab_act:cnf_unexp", "PS RAB Activations confirmed in unexpected state" },
+	[HNB_CTR_RANAP_CS_RAB_ACT_CNF_UNEXP] = {
+		"ranap:cs:rab_act:cnf_unexp", "CS RAB Activations confirmed in unexpected state" },
+
+	[HNB_CTR_RANAP_PS_RAB_ACT_FAIL] = {
+		"ranap:ps:rab_act:fail", "PS RAB Activations failed" },
+	[HNB_CTR_RANAP_CS_RAB_ACT_FAIL] = {
+		"ranap:cs:rab_act:fail", "CS RAB Activations failed" },
+	[HNB_CTR_RANAP_PS_RAB_ACT_FAIL_UNEXP] = {
+		"ranap:ps:rab_act:fail_unexp", "PS RAB Activations failed in unexpected state" },
+	[HNB_CTR_RANAP_CS_RAB_ACT_FAIL_UNEXP] = {
+		"ranap:cs:rab_act:fail_unexp", "CS RAB Activations failed in unexpected state" },
+
+
+	[HNB_CTR_RANAP_PS_RAB_MOD_REQ] = {
+		"ranap:ps:rab_mod:req", "PS RAB Modifications requested" },
+	[HNB_CTR_RANAP_CS_RAB_MOD_REQ] = {
+		"ranap:cs:rab_mod:req", "CS RAB Modifications requested" },
+
+	[HNB_CTR_RANAP_PS_RAB_MOD_CNF] = {
+		"ranap:ps:rab_mod:cnf", "PS RAB Modifications confirmed" },
+	[HNB_CTR_RANAP_CS_RAB_MOD_CNF] = {
+		"ranap:cs:rab_mod:cnf", "CS RAB Modifications confirmed" },
+
+	[HNB_CTR_RANAP_PS_RAB_MOD_FAIL] = {
+		"ranap:ps:rab_mod:fail", "PS RAB Modifications failed" },
+	[HNB_CTR_RANAP_CS_RAB_MOD_FAIL] = {
+		"ranap:cs:rab_mod:fail", "CS RAB Modifications failed" },
+
+	[HNB_CTR_RANAP_PS_RAB_REL_REQ] = {
+		"ranap:ps:rab_rel:req:normal", "PS RAB Release requested (by CN), normal" },
+	[HNB_CTR_RANAP_CS_RAB_REL_REQ] = {
+		"ranap:cs:rab_rel:req:normal", "CS RAB Release requested (by CN), normal" },
+	[HNB_CTR_RANAP_PS_RAB_REL_REQ_ABNORMAL] = {
+		"ranap:ps:rab_rel:req:abnormal", "PS RAB Release requested (by CN), abnormal" },
+	[HNB_CTR_RANAP_CS_RAB_REL_REQ_ABNORMAL] = {
+		"ranap:cs:rab_rel:req:abnormal", "CS RAB Release requested (by CN), abnormal" },
+	[HNB_CTR_RANAP_PS_RAB_REL_REQ_UNEXP] = {
+		"ranap:ps:rab_rel:req:unexp", "PS RAB Release requested (by CN) in unexpected state" },
+	[HNB_CTR_RANAP_CS_RAB_REL_REQ_UNEXP] = {
+		"ranap:cs:rab_rel:req:unexp", "CS RAB Release requested (by CN) in unexpected state" },
+
+	[HNB_CTR_RANAP_PS_RAB_REL_CNF] = {
+		"ranap:ps:rab_rel:cnf", "PS RAB Release confirmed" },
+	[HNB_CTR_RANAP_CS_RAB_REL_CNF] = {
+		"ranap:cs:rab_rel:cnf", "CS RAB Release confirmed" },
+	[HNB_CTR_RANAP_PS_RAB_REL_CNF_UNEXP] = {
+		"ranap:ps:rab_rel:cnf_unexp", "PS RAB Release confirmed in unexpected state" },
+	[HNB_CTR_RANAP_CS_RAB_REL_CNF_UNEXP] = {
+		"ranap:cs:rab_rel:cnf_unexp", "CS RAB Release confirmed in unexpected state" },
+
+	[HNB_CTR_RANAP_PS_RAB_REL_FAIL] = {
+		"ranap:ps:rab_rel:fail", "PS RAB Release failed" },
+	[HNB_CTR_RANAP_CS_RAB_REL_FAIL] = {
+		"ranap:cs:rab_rel:fail", "CS RAB Release failed" },
+	[HNB_CTR_RANAP_PS_RAB_REL_FAIL_UNEXP] = {
+		"ranap:ps:rab_rel:fail_unexp", "PS RAB Release failed in unexpected state" },
+	[HNB_CTR_RANAP_CS_RAB_REL_FAIL_UNEXP] = {
+		"ranap:cs:rab_rel:fail_unexp", "CS RAB Release failed in unexpected state" },
+
+	[HNB_CTR_RANAP_PS_RAB_REL_IMPLICIT] = {
+		"ranap:ps:rab_rel:implicit:normal", "PS RAB Release implicit (during Iu Release), normal" },
+	[HNB_CTR_RANAP_CS_RAB_REL_IMPLICIT] = {
+		"ranap:cs:rab_rel:implicit:normal", "CS RAB Release implicit (during Iu Release), normal" },
+	[HNB_CTR_RANAP_PS_RAB_REL_IMPLICIT_ABNORMAL] = {
+		"ranap:ps:rab_rel:implicit:abnormal", "PS RAB Release implicit (during Iu Release), abnormal" },
+	[HNB_CTR_RANAP_CS_RAB_REL_IMPLICIT_ABNORMAL] = {
+		"ranap:cs:rab_rel:implicit:abnormal", "CS RAB Release implicit (during Iu Release), abnormal" },
+
+	[HNB_CTR_RUA_ERR_IND] = {
+		"rua:error_ind", "Received RUA Error Indications" },
+
+	[HNB_CTR_RUA_PS_CONNECT_UL] = {
+		"rua:ps:connect:ul", "Received RUA Connect requests (PS Domain)" },
+	[HNB_CTR_RUA_CS_CONNECT_UL] = {
+		"rua:cs:connect:ul", "Received RUA Connect requests (CS Domain)" },
+
+	[HNB_CTR_RUA_PS_DISCONNECT_UL] = {
+		"rua:ps:disconnect:ul", "Received RUA Disconnect requests in uplink (PS Domain)" },
+	[HNB_CTR_RUA_CS_DISCONNECT_UL] = {
+		"rua:cs:disconnect:ul", "Received RUA Disconnect requests in uplink (CS Domain)" },
+	[HNB_CTR_RUA_PS_DISCONNECT_DL] = {
+		"rua:ps:disconnect:dl", "Transmitted RUA Disconnect requests in downlink (PS Domain)" },
+	[HNB_CTR_RUA_CS_DISCONNECT_DL] = {
+		"rua:cs:disconnect:dl", "Transmitted RUA Disconnect requests in downlink (CS Domain)" },
+
+	[HNB_CTR_RUA_PS_DT_UL] = {
+		"rua:ps:direct_transfer:ul", "Received RUA DirectTransfer in uplink (PS Domain)" },
+	[HNB_CTR_RUA_CS_DT_UL] = {
+		"rua:cs:direct_transfer:ul", "Received RUA DirectTransfer in uplink (CS Domain)" },
+	[HNB_CTR_RUA_PS_DT_DL] = {
+		"rua:ps:direct_transfer:dl", "Transmitted RUA DirectTransfer in downlink (PS Domain)" },
+	[HNB_CTR_RUA_CS_DT_DL] = {
+		"rua:cs:direct_transfer:dl", "Transmitted RUA DirectTransfer in downlink (CS Domain)" },
+
+	[HNB_CTR_RUA_UDT_UL] = {
+		"rua:unit_data:ul", "Received RUA UnitData (UDT) in uplink" },
+	[HNB_CTR_RUA_UDT_DL] = {
+		"rua:unit_data:dl", "Transmitted RUA UnitData (UDT) in downlink" },
+
+	[HNB_CTR_PS_PAGING_ATTEMPTED] = {
+		"paging:ps:attempted", "Transmitted PS Paging requests" },
+	[HNB_CTR_CS_PAGING_ATTEMPTED] = {
+		"paging:cs:attempted", "Transmitted CS Paging requests" },
+
+	[HNB_CTR_RAB_ACTIVE_MILLISECONDS_TOTAL] = {
+		"rab:cs:active_milliseconds:total", "Cumulative number of milliseconds of CS RAB activity" },
+
+	[HNB_CTR_DTAP_CS_LU_REQ] = { "dtap:cs:location_update:req", "CS Location Update Requests" },
+	[HNB_CTR_DTAP_CS_LU_ACC] = { "dtap:cs:location_update:accept", "CS Location Update Accepts" },
+	[HNB_CTR_DTAP_CS_LU_REJ] = { "dtap:cs:location_update:reject", "CS Location Update Rejects" },
+
+	[HNB_CTR_DTAP_PS_ATT_REQ] = { "dtap:ps:attach:req", "PS Attach Requests" },
+	[HNB_CTR_DTAP_PS_ATT_ACK] = { "dtap:ps:attach:accept", "PS Attach Accepts" },
+	[HNB_CTR_DTAP_PS_ATT_REJ] = { "dtap:ps:attach:reject", "PS Attach Rejects" },
+
+	[HNB_CTR_DTAP_PS_RAU_REQ] = { "dtap:ps:routing_area_update:req", "PS Routing Area Update Requests" },
+	[HNB_CTR_DTAP_PS_RAU_ACK] = { "dtap:ps:routing_area_update:accept", "PS Routing Area Update Accepts" },
+	[HNB_CTR_DTAP_PS_RAU_REJ] = { "dtap:ps:routing_area_update:reject", "PS Routing Area Update Rejects" },
+
+	[HNB_CTR_GTPU_PACKETS_UL] = {
+		"gtpu:packets:ul",
+		"Count of GTP-U packets received from the HNB",
+	},
+	[HNB_CTR_GTPU_TOTAL_BYTES_UL] = {
+		"gtpu:total_bytes:ul",
+		"Count of total GTP-U bytes received from the HNB, including the GTP-U/UDP/IP headers",
+	},
+	[HNB_CTR_GTPU_UE_BYTES_UL] = {
+		"gtpu:ue_bytes:ul",
+		"Assuming an IP header length of 20 bytes, GTP-U bytes received from the HNB, excluding the GTP-U/UDP/IP headers",
+	},
+	[HNB_CTR_GTPU_PACKETS_DL] = {
+		"gtpu:packets:dl",
+		"Count of GTP-U packets sent to the HNB",
+	},
+	[HNB_CTR_GTPU_TOTAL_BYTES_DL] = {
+		"gtpu:total_bytes:dl",
+		"Count of total GTP-U bytes sent to the HNB, including the GTP-U/UDP/IP headers",
+	},
+	[HNB_CTR_GTPU_UE_BYTES_DL] = {
+		"gtpu:ue_bytes:dl",
+		"Assuming an IP header length of 20 bytes, GTP-U bytes sent to the HNB, excluding the GTP-U/UDP/IP headers",
+	},
+
+};
+
+const struct rate_ctr_group_desc hnb_ctrg_desc = {
+	"hnb",
+	"hNodeB",
+	OSMO_STATS_CLASS_GLOBAL,
+	ARRAY_SIZE(hnb_ctr_description),
+	hnb_ctr_description,
+};
+
+const struct osmo_stat_item_desc hnb_stat_desc[] = {
+	[HNB_STAT_UPTIME_SECONDS] = { "uptime:seconds", "Seconds of uptime", "s", 60, 0 },
+};
+
+const struct osmo_stat_item_group_desc hnb_statg_desc = {
+	.group_name_prefix = "hnb",
+	.group_description = "hNodeB",
+	.class_id = OSMO_STATS_CLASS_GLOBAL,
+	.num_items = ARRAY_SIZE(hnb_stat_desc),
+	.item_desc = hnb_stat_desc,
+};
+
+static void hnb_persistent_disconnected_timeout_cb(void *data)
+{
+	hnb_persistent_free(data);
+}
+
+static void hnb_persistent_disconnected_timeout_schedule(struct hnb_persistent *hnbp)
+{
+	unsigned long period_s = osmo_tdef_get(hnbgw_T_defs, -35, OSMO_TDEF_S, 60*60*24*7);
+	if (period_s < 1) {
+		LOG_HNBP(hnbp, LOGL_INFO,
+			 "timer X35 is zero, not setting a disconnected timeout for this hnb-persistent instance.\n");
+		return;
+	}
+	/* It is fine if the timer is already active, osmo_timer_del() is done implicitly by the osmo_timer API. */
+	osmo_timer_setup(&hnbp->disconnected_timeout, hnb_persistent_disconnected_timeout_cb, hnbp);
+	osmo_timer_schedule(&hnbp->disconnected_timeout, period_s, 0);
+}
+
+struct hnb_persistent *hnb_persistent_alloc(const struct umts_cell_id *id)
+{
+	struct hnb_persistent *hnbp = talloc_zero(g_hnbgw, struct hnb_persistent);
+	if (!hnbp)
+		return NULL;
+
+	hnbp->id = *id;
+	hnbp->id_str = talloc_strdup(hnbp, umts_cell_id_to_str(id));
+	hnbp->ctrs = rate_ctr_group_alloc(hnbp, &hnb_ctrg_desc, 0);
+	if (!hnbp->ctrs)
+		goto out_free;
+	rate_ctr_group_set_name(hnbp->ctrs, hnbp->id_str);
+	hnbp->statg = osmo_stat_item_group_alloc(hnbp, &hnb_statg_desc, 0);
+	if (!hnbp->statg)
+		goto out_free_ctrs;
+	osmo_stat_item_group_set_name(hnbp->statg, hnbp->id_str);
+
+	llist_add(&hnbp->list, &g_hnbgw->hnb_persistent_list);
+	hash_add(g_hnbgw->hnb_persistent_by_id, &hnbp->node_by_id, umts_cell_id_hash(&hnbp->id));
+
+	if (g_hnbgw->nft_kpi.active)
+		nft_kpi_hnb_persistent_add(hnbp);
+
+	/* Normally the disconnected timer runs only when the hNodeB is not currently connected on Iuh. This here is paranoia:
+	 * In case we have to HNBAP HNB Register Reject, the disconnected timer should be active on this unused hnbp.
+	 * On success, hnb_persistent_registered() will stop the disconnected timer directly after this. */
+	hnb_persistent_disconnected_timeout_schedule(hnbp);
+
+	return hnbp;
+
+out_free_ctrs:
+	rate_ctr_group_free(hnbp->ctrs);
+out_free:
+	talloc_free(hnbp);
+	return NULL;
+}
+
+struct hnb_persistent *hnb_persistent_find_by_id(const struct umts_cell_id *id)
+{
+	struct hnb_persistent *hnbp;
+	uint32_t id_hash = umts_cell_id_hash(id);
+	hash_for_each_possible(g_hnbgw->hnb_persistent_by_id, hnbp, node_by_id, id_hash) {
+		if (umts_cell_id_equal(&hnbp->id, id))
+			return hnbp;
+	}
+	return NULL;
+}
+
+/* Read the peer's remote IP address from the Iuh conn's fd, and set up GTP-U counters for that remote address. */
+static void hnb_persistent_update_remote_addr(struct hnb_persistent *hnbp)
+{
+	socklen_t socklen;
+	struct osmo_sockaddr osa;
+	struct osmo_sockaddr_str remote_str;
+	int fd;
+
+	fd = osmo_stream_srv_get_fd(hnbp->ctx->conn);
+	if (fd < 0) {
+		LOG_HNBP(hnbp, LOGL_ERROR, "no active socket fd, cannot set up traffic counters\n");
+		return;
+	}
+
+	socklen = sizeof(struct osmo_sockaddr);
+	if (getpeername(fd, &osa.u.sa, &socklen)) {
+		LOG_HNBP(hnbp, LOGL_ERROR, "cannot read remote address, cannot set up traffic counters\n");
+		return;
+	}
+	if (osmo_sockaddr_str_from_osa(&remote_str, &osa)) {
+		LOG_HNBP(hnbp, LOGL_ERROR, "cannot parse remote address, cannot set up traffic counters\n");
+		return;
+	}
+
+	/* We got the remote address from the Iuh link (RUA), and now we are blatantly assuming that the hNodeB has its
+	 * GTP endpoint on the same IP address, just with UDP port 2152 (the fixed GTP port as per 3GPP spec). */
+	remote_str.port = 2152;
+
+	if (nft_kpi_hnb_start(hnbp, &remote_str))
+		LOG_HNBP(hnbp, LOGL_ERROR, "failed to set up traffic counters\n");
+}
+
+/* Whenever HNBAP registers a HNB, hnbgw_hnbap.c calls this function to let the hnb_persistent update its state to the
+ * (new) remote address being active. When calling this function, a hnbp->ctx should be present, with an active
+ * osmo_stream_srv conn. */
+void hnb_persistent_registered(struct hnb_persistent *hnbp)
+{
+	if (!hnbp->ctx) {
+		LOG_HNBP(hnbp, LOGL_ERROR, "hnb_persistent_registered() invoked, but there is no hnb_ctx\n");
+		return;
+	}
+
+	/* The hNodeB is now connected, i.e. not disconnected. */
+	osmo_timer_del(&hnbp->disconnected_timeout);
+
+	/* start counting traffic */
+	if (g_hnbgw->nft_kpi.active)
+		hnb_persistent_update_remote_addr(hnbp);
+}
+
+/* Whenever a HNB is regarded as no longer registered (HNBAP HNB De-Register, or the Iuh link drops), this function is
+ * called to to let the hnb_persistent update its state to the hNodeB being disconnected. Clear the ctx->persistent and
+ * hnbp->ctx relations; do not delete the hnb_persistent instance. */
+void hnb_persistent_deregistered(struct hnb_persistent *hnbp)
+{
+	/* clear out cross references of hnb_context and hnb_persistent */
+	if (hnbp->ctx) {
+		if (hnbp->ctx->persistent == hnbp)
+			hnbp->ctx->persistent = NULL;
+		hnbp->ctx = NULL;
+	}
+
+	/* stop counting traffic */
+	nft_kpi_hnb_stop(hnbp);
+
+	/* The hNodeB is now disconnected. Clear out hnb_persistent when the disconnected timeout has passed. */
+	hnb_persistent_disconnected_timeout_schedule(hnbp);
+}
+
+void hnb_persistent_free(struct hnb_persistent *hnbp)
+{
+	/* FIXME: check if in use? */
+	osmo_timer_del(&hnbp->disconnected_timeout);
+	nft_kpi_hnb_stop(hnbp);
+	nft_kpi_hnb_persistent_remove(hnbp);
+	osmo_stat_item_group_free(hnbp->statg);
+	rate_ctr_group_free(hnbp->ctrs);
+	llist_del(&hnbp->list);
+	hash_del(&hnbp->node_by_id);
+	talloc_free(hnbp);
+}
+
+/* return the amount of time the HNB is up (hnbp->ctx != NULL) or down (hnbp->ctx == NULL) */
+unsigned long long hnbp_get_updowntime(const struct hnb_persistent *hnbp)
+{
+	struct timespec tp;
+
+	if (!hnbp->updowntime)
+		return 0;
+
+	if (osmo_clock_gettime(CLOCK_MONOTONIC, &tp) != 0)
+		return 0;
+
+	return difftime(tp.tv_sec, hnbp->updowntime);
+}

src/osmo-hnbgw/hnbgw.c

@@ -1,7 +1,7 @@
-/* main application for hnb-gw part of osmo-iuh */
+/* kitchen sink for OsmoHNBGW implementation */
 
-/* (C) 2015 by Harald Welte <laforge@gnumonks.org>
- * (C) 2016 by sysmocom s.f.m.c. GmbH <info@sysmocom.de>
+/* (C) 2015,2024 by Harald Welte <laforge@gnumonks.org>
+ * (C) 2016-2025 by sysmocom s.f.m.c. GmbH <info@sysmocom.de>
  * All Rights Reserved
  *
  * This program is free software; you can redistribute it and/or modify
@@ -19,339 +19,138 @@
  *
  */
 
-#include "config.h"
+#include <inttypes.h>
 
-#include <unistd.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <getopt.h>
-#include <errno.h>
-#include <signal.h>
-#include <stdbool.h>
-
-#include <sys/types.h>
-#include <sys/socket.h>
 #include <netinet/in.h>
 #include <netinet/sctp.h>
-#include <arpa/inet.h>
 
-#include <osmocom/core/application.h>
-#include <osmocom/core/talloc.h>
-#include <osmocom/core/select.h>
-#include <osmocom/core/logging.h>
-#include <osmocom/core/socket.h>
-#include <osmocom/core/msgb.h>
-#include <osmocom/core/write_queue.h>
-#include <osmocom/ctrl/control_if.h>
-#include <osmocom/ctrl/control_cmd.h>
-#include <osmocom/ctrl/control_vty.h>
-#include <osmocom/ctrl/ports.h>
-#include <osmocom/vty/telnet_interface.h>
-#include <osmocom/vty/logging.h>
-#include <osmocom/vty/command.h>
-#include <osmocom/vty/ports.h>
+#include <osmocom/core/stats.h>
+#include <osmocom/core/rate_ctr.h>
+#include <osmocom/core/stat_item.h>
+#include <osmocom/core/jhash.h>
+
+#include <osmocom/vty/vty.h>
+
+#include <osmocom/gsm/gsm23236.h>
 
 #include <osmocom/netif/stream.h>
 
-#include <osmocom/ranap/ranap_common.h>
-
-#include <osmocom/sigtran/protocol/m3ua.h>
-#include <osmocom/sigtran/sccp_sap.h>
+#include "config.h"
+#if ENABLE_PFCP
+#include <osmocom/pfcp/pfcp_proto.h>
+#endif
 
+#include <osmocom/hnbgw/hnb.h>
+#include <osmocom/hnbgw/hnb_persistent.h>
 #include <osmocom/hnbgw/hnbgw.h>
 #include <osmocom/hnbgw/hnbgw_hnbap.h>
 #include <osmocom/hnbgw/hnbgw_rua.h>
 #include <osmocom/hnbgw/hnbgw_cn.h>
 #include <osmocom/hnbgw/context_map.h>
+#include <osmocom/hnbgw/mgw_fsm.h>
+#include <osmocom/hnbgw/tdefs.h>
 
-static const char * const osmo_hnbgw_copyright =
-	"OsmoHNBGW - Osmocom Home Node B Gateway implementation\r\n"
-	"Copyright (C) 2016 by sysmocom s.f.m.c. GmbH <info@sysmocom.de>\r\n"
-	"Contributions by Daniel Willmann, Harald Welte, Neels Hofmeyr\r\n"
-	"License AGPLv3+: GNU AGPL version 3 or later <http://gnu.org/licenses/agpl-3.0.html>\r\n"
-	"This is free software: you are free to change and redistribute it.\r\n"
-	"There is NO WARRANTY, to the extent permitted by law.\r\n";
+struct hnbgw *g_hnbgw = NULL;
 
-static void *tall_hnb_ctx;
+const struct value_string ranap_domain_names[] = {
+	{ DOMAIN_CS, "CS" },
+	{ DOMAIN_PS, "PS" },
+	{}
+};
 
-static struct hnb_gw *g_hnb_gw;
 
-static struct hnb_gw *hnb_gw_create(void *ctx)
+/* timer call-back: Update the HNB_STAT_UPTIME_SECONDS stat item of each hnb_persistent */
+static void hnbgw_store_hnb_uptime(void *data)
 {
-	struct hnb_gw *gw = talloc_zero(ctx, struct hnb_gw);
+	struct hnb_persistent *hnbp;
 
-	/* strdup so we can easily talloc_free in the VTY code */
-	gw->config.iuh_local_ip = talloc_strdup(gw, HNBGW_LOCAL_IP_DEFAULT);
-	gw->config.iuh_local_port = IUH_DEFAULT_SCTP_PORT;
-	gw->config.log_prefix_hnb_id = true;
+	llist_for_each_entry(hnbp, &g_hnbgw->hnb_persistent_list, list) {
+		HNBP_STAT_SET(hnbp, HNB_STAT_UPTIME_SECONDS, hnbp->ctx != NULL ? hnbp_get_updowntime(hnbp) : 0);
+	}
 
-	gw->next_ue_ctx_id = 23;
-	INIT_LLIST_HEAD(&gw->hnb_list);
-	INIT_LLIST_HEAD(&gw->ue_list);
-
-	context_map_init(gw);
-
-	return gw;
+	osmo_timer_schedule(&g_hnbgw->store_uptime_timer, STORE_UPTIME_INTERVAL, 0);
 }
 
-struct hnb_context *hnb_context_by_id(struct hnb_gw *gw, uint32_t cid)
+static void hnbgw_store_hnb_rab_durations(void *data)
 {
 	struct hnb_context *hnb;
 
-	llist_for_each_entry(hnb, &gw->hnb_list, list) {
-		if (hnb->id.cid == cid)
-			return hnb;
+	llist_for_each_entry(hnb, &g_hnbgw->hnb_list, list) {
+		if (!hnb->persistent)
+			continue;
+		hnb_store_rab_durations(hnb);
 	}
 
-	return NULL;
+	/* Keep this timer ticking */
+	osmo_timer_schedule(&g_hnbgw->hnb_store_rab_durations_timer, HNB_STORE_RAB_DURATIONS_INTERVAL, 0);
 }
 
-struct hnb_context *hnb_context_by_identity_info(struct hnb_gw *gw, const char *identity_info)
+/***********************************************************************
+ * UE Context
+ ***********************************************************************/
+
+uint32_t get_next_ue_ctx_id(void)
 {
-	struct hnb_context *hnb;
-
-	llist_for_each_entry(hnb, &gw->hnb_list, list) {
-		if (strcmp(identity_info, hnb->identity_info) == 0)
-			return hnb;
-	}
-
-	return NULL;
+	return g_hnbgw->next_ue_ctx_id++;
 }
 
-
-unsigned hnb_contexts(const struct hnb_gw *gw)
+int hnbgw_mgw_setup(void)
 {
-	unsigned num_ctx = 0;
-	struct hnb_context *hnb;
+	struct mgcp_client *mgcp_client_single;
+	unsigned int pool_members_initalized;
 
-	llist_for_each_entry(hnb, &gw->hnb_list, list) {
-		num_ctx++;
-	}
-
-	return num_ctx;
-}
-
-struct ue_context *ue_context_by_id(struct hnb_gw *gw, uint32_t id)
-{
-	struct ue_context *ue;
-
-	llist_for_each_entry(ue, &gw->ue_list, list) {
-		if (ue->context_id == id)
-			return ue;
-	}
-	return NULL;
-
-}
-
-struct ue_context *ue_context_by_imsi(struct hnb_gw *gw, const char *imsi)
-{
-	struct ue_context *ue;
-
-	llist_for_each_entry(ue, &gw->ue_list, list) {
-		if (!strcmp(ue->imsi, imsi))
-			return ue;
-	}
-	return NULL;
-}
-
-struct ue_context *ue_context_by_tmsi(struct hnb_gw *gw, uint32_t tmsi)
-{
-	struct ue_context *ue;
-
-	llist_for_each_entry(ue, &gw->ue_list, list) {
-		if (ue->tmsi == tmsi)
-			return ue;
-	}
-	return NULL;
-}
-
-void ue_context_free_by_hnb(struct hnb_gw *gw, const struct hnb_context *hnb)
-{
-	struct ue_context *ue, *tmp;
-
-	llist_for_each_entry_safe(ue, tmp, &gw->ue_list, list) {
-		if (ue->hnb == hnb)
-			ue_context_free(ue);
-	}
-}
-
-static uint32_t get_next_ue_ctx_id(struct hnb_gw *gw)
-{
-	uint32_t id;
-
-	do {
-		id = gw->next_ue_ctx_id++;
-	} while (ue_context_by_id(gw, id));
-
-	return id;
-}
-
-struct ue_context *ue_context_alloc(struct hnb_context *hnb, const char *imsi,
-				    uint32_t tmsi)
-{
-	struct ue_context *ue;
-
-	ue = talloc_zero(tall_hnb_ctx, struct ue_context);
-	if (!ue)
-		return NULL;
-
-	ue->hnb = hnb;
-	if (imsi)
-		OSMO_STRLCPY_ARRAY(ue->imsi, imsi);
-	else
-		ue->imsi[0] = '\0';
-	ue->tmsi = tmsi;
-	ue->context_id = get_next_ue_ctx_id(hnb->gw);
-	llist_add_tail(&ue->list, &hnb->gw->ue_list);
-
-	LOGP(DHNBAP, LOGL_INFO, "created UE context: id 0x%x, imsi %s, tmsi 0x%x\n",
-	     ue->context_id, imsi? imsi : "-", tmsi);
-
-	return ue;
-}
-
-void ue_context_free(struct ue_context *ue)
-{
-	llist_del(&ue->list);
-	talloc_free(ue);
-}
-
-static int hnb_read_cb(struct osmo_stream_srv *conn)
-{
-	struct hnb_context *hnb = osmo_stream_srv_get_data(conn);
-	struct msgb *msg = msgb_alloc(IUH_MSGB_SIZE, "Iuh rx");
-	int rc;
-
-	if (!msg)
-		return -ENOMEM;
-
-	/* we store a reference to the HomeNodeB in the msg->dest for the
-	 * benefit of varoius downstream processing functions */
-	msg->dst = hnb;
-
-	rc = osmo_stream_srv_recv(conn, msg);
-	if (rc == -EAGAIN) {
-		/* Notification received */
-		msgb_free(msg);
+	/* Initialize MGW pool. This initalizes and connects all MGCP clients that are currently configured in
+	 * the pool. Adding additional MGCP clients to the pool is possible but the user has to configure and
+	 * (re)connect them manually from the VTY. */
+	if (!mgcp_client_pool_empty(g_hnbgw->mgw_pool)) {
+		pool_members_initalized = mgcp_client_pool_connect(g_hnbgw->mgw_pool);
+		if (!pool_members_initalized) {
+			LOGP(DMGW, LOGL_ERROR, "MGW pool failed to initialize any pool members\n");
+			return -EINVAL;
+		}
+		LOGP(DMGW, LOGL_NOTICE,
+		     "MGW pool with %u pool members configured, (ignoring MGW configuration in VTY node 'mgcp').\n",
+		     pool_members_initalized);
 		return 0;
-	} else if (rc < 0) {
-		LOGHNB(hnb, DMAIN, LOGL_ERROR, "Error during sctp_recvmsg()\n");
-		/* FIXME: clean up after disappeared HNB */
-		hnb_context_release(hnb);
-		goto out;
-	} else if (rc == 0) {
-		hnb_context_release(hnb);
-		rc = -1;
-
-		goto out;
-	} else {
-		msgb_put(msg, rc);
 	}
 
-	switch (msgb_sctp_ppid(msg)) {
-	case IUH_PPI_HNBAP:
-		hnb->hnbap_stream = msgb_sctp_stream(msg);
-		rc = hnbgw_hnbap_rx(hnb, msg);
-		break;
-	case IUH_PPI_RUA:
-		hnb->rua_stream = msgb_sctp_stream(msg);
-		rc = hnbgw_rua_rx(hnb, msg);
-		break;
-	case IUH_PPI_SABP:
-	case IUH_PPI_RNA:
-	case IUH_PPI_PUA:
-		LOGHNB(hnb, DMAIN, LOGL_ERROR, "Unimplemented SCTP PPID=%lu received\n", msgb_sctp_ppid(msg));
-		rc = 0;
-		break;
-	default:
-		LOGHNB(hnb, DMAIN, LOGL_ERROR, "Unknown SCTP PPID=%lu received\n", msgb_sctp_ppid(msg));
-		rc = 0;
-		break;
+	/* Initialize and connect a single MGCP client. This MGCP client will appear as the one and only pool
+	 * member if there is no MGW pool configured. */
+	LOGP(DMGW, LOGL_NOTICE, "No MGW pool configured, using MGW configuration in VTY node 'mgcp'\n");
+	mgcp_client_single = mgcp_client_init(g_hnbgw, g_hnbgw->config.mgcp_client);
+	if (!mgcp_client_single) {
+		LOGP(DMGW, LOGL_ERROR, "MGW (single) client initalization failed\n");
+		return -EINVAL;
 	}
-
-out:
-	msgb_free(msg);
-	return rc;
-}
-
-struct hnb_context *hnb_context_alloc(struct hnb_gw *gw, struct osmo_stream_srv_link *link, int new_fd)
-{
-	struct hnb_context *ctx;
-
-	ctx = talloc_zero(tall_hnb_ctx, struct hnb_context);
-	if (!ctx)
-		return NULL;
-	INIT_LLIST_HEAD(&ctx->map_list);
-
-	ctx->gw = gw;
-	ctx->conn = osmo_stream_srv_create(tall_hnb_ctx, link, new_fd, hnb_read_cb, NULL, ctx);
-	if (!ctx->conn) {
-		LOGP(DMAIN, LOGL_INFO, "error while creating connection\n");
-		talloc_free(ctx);
-		return NULL;
+	if (mgcp_client_connect(mgcp_client_single)) {
+		LOGP(DMGW, LOGL_ERROR, "MGW (single) connect failed at (%s:%u)\n",
+		     g_hnbgw->config.mgcp_client->remote_addr,
+		     g_hnbgw->config.mgcp_client->remote_port);
+		return -EINVAL;
 	}
-
-	llist_add_tail(&ctx->list, &gw->hnb_list);
-	return ctx;
-}
-
-static const char *umts_cell_id_name(const struct umts_cell_id *ucid)
-{
-	static __thread char buf[40];
-
-	snprintf(buf, sizeof(buf), "%u-%u-L%u-R%u-S%u", ucid->mcc, ucid->mnc, ucid->lac, ucid->rac, ucid->sac);
-	return buf;
-}
-
-const char *hnb_context_name(struct hnb_context *ctx)
-{
-	if (!ctx)
-		return "NULL";
-
-	if (ctx->gw->config.log_prefix_hnb_id)
-		return ctx->identity_info;
-	else
-		return umts_cell_id_name(&ctx->id);
-}
-
-void hnb_context_release(struct hnb_context *ctx)
-{
-	struct hnbgw_context_map *map, *map2;
-
-	/* remove from the list of HNB contexts */
-	llist_del(&ctx->list);
-
-	/* deactivate all context maps */
-	llist_for_each_entry_safe(map, map2, &ctx->map_list, hnb_list) {
-		/* remove it from list, as HNB context will soon be
-		 * gone.  Let's hope the second osmo_llist_del in the
-		 * map garbage collector works fine? */
-		llist_del(&map->hnb_list);
-		llist_del(&map->cn_list);
-		context_map_deactivate(map);
-	}
-	ue_context_free_by_hnb(ctx->gw, ctx);
-
-	osmo_stream_srv_destroy(ctx->conn);
-
-	talloc_free(ctx);
-}
-
-/*! call-back when the listen FD has something to read */
-static int accept_cb(struct osmo_stream_srv_link *srv, int fd)
-{
-	struct hnb_gw *gw = osmo_stream_srv_link_get_data(srv);
-	struct hnb_context *ctx;
-
-	ctx = hnb_context_alloc(gw, srv, fd);
-	if (!ctx)
-		return -ENOMEM;
+	mgcp_client_pool_register_single(g_hnbgw->mgw_pool, mgcp_client_single);
 
 	return 0;
 }
 
-static const struct log_info_cat log_cat[] = {
+struct msgb *hnbgw_ranap_msg_alloc(const char *name)
+{
+	struct msgb *ranap_msg;
+	ranap_msg = msgb_alloc_c(OTC_SELECT, sizeof(struct osmo_scu_prim) + 1500, name);
+	msgb_reserve(ranap_msg, sizeof(struct osmo_scu_prim));
+	ranap_msg->l2h = ranap_msg->data;
+	return ranap_msg;
+}
+
+#define HNBGW_COPYRIGHT \
+	"OsmoHNBGW - Osmocom Home Node B Gateway implementation\r\n" \
+	"Copyright (C) 2016-2024 by sysmocom s.f.m.c. GmbH <info@sysmocom.de>\r\n" \
+	"Contributions by Daniel Willmann, Harald Welte, Neels Hofmeyr\r\n" \
+	"License AGPLv3+: GNU AGPL version 3 or later <http://gnu.org/licenses/agpl-3.0.html>\r\n" \
+	"This is free software: you are free to change and redistribute it.\r\n" \
+	"There is NO WARRANTY, to the extent permitted by law.\r\n"
+
+static const struct log_info_cat hnbgw_log_cat[] = {
 	[DMAIN] = {
 		.name = "DMAIN", .loglevel = LOGL_NOTICE, .enabled = 1,
 		.color = "",
@@ -372,329 +171,76 @@ static const struct log_info_cat log_cat[] = {
 		.color = "",
 		.description = "RAN Application Part",
 	},
+	[DMGW] = {
+		.name = "DMGW", .loglevel = LOGL_NOTICE, .enabled = 1,
+		.color = "\033[1;33m",
+		.description = "Media Gateway",
+	},
+	[DHNB] = {
+		.name = "DHNB", .loglevel = LOGL_NOTICE, .enabled = 1,
+		.color = OSMO_LOGCOLOR_CYAN,
+		.description = "HNB side (via RUA)",
+	},
+	[DCN] = {
+		.name = "DCN", .loglevel = LOGL_NOTICE, .enabled = 1,
+		.color = OSMO_LOGCOLOR_DARKYELLOW,
+		.description = "Core Network side (via SCCP)",
+	},
+	[DNFT] = {
+		.name = "DNFT", .loglevel = LOGL_NOTICE, .enabled = 1,
+		.color = OSMO_LOGCOLOR_BLUE,
+		.description = "nftables interaction for retrieving stats",
+	},
 };
 
-static const struct log_info hnbgw_log_info = {
-	.cat = log_cat,
-	.num_cat = ARRAY_SIZE(log_cat),
+const struct log_info hnbgw_log_info = {
+	.cat = hnbgw_log_cat,
+	.num_cat = ARRAY_SIZE(hnbgw_log_cat),
 };
 
-static struct vty_app_info vty_info = {
-	.name		= "OsmoHNBGW",
-	.version	= PACKAGE_VERSION,
-	.go_parent_cb	= hnbgw_vty_go_parent,
+struct vty_app_info hnbgw_vty_info = {
+	.name = "OsmoHNBGW",
+	.version = PACKAGE_VERSION,
+	.go_parent_cb = hnbgw_vty_go_parent,
+	.copyright = HNBGW_COPYRIGHT,
 };
 
-static struct {
-	int daemonize;
-	const char *config_file;
-	bool log_disable_color;
-	bool log_enable_timestamp;
-	int log_level;
-	const char *log_category_mask;
-} hnbgw_cmdline_config = {
-	0,
-	"osmo-hnbgw.cfg",
-	false,
-	false,
-	0,
-	NULL,
-};
-
-static void print_usage()
+void g_hnbgw_alloc(void *ctx)
 {
-	printf("Usage: osmo-hnbgw\n");
-}
-
-static void print_help()
-{
-	printf("  -h --help                  This text.\n");
-	printf("  -d option --debug=DHNBAP:DRUA:DRANAP:DMAIN  Enable debugging.\n");
-	printf("  -D --daemonize             Fork the process into a background daemon.\n");
-	printf("  -c --config-file filename  The config file to use.\n");
-	printf("  -s --disable-color\n");
-	printf("  -T --timestamp             Prefix every log line with a timestamp.\n");
-	printf("  -V --version               Print the version of OsmoHNBGW.\n");
-	printf("  -e --log-level number      Set a global loglevel.\n");
-
-	printf("\nVTY reference generation:\n");
-	printf("     --vty-ref-mode MODE        VTY reference generation mode (e.g. 'expert').\n");
-	printf("     --vty-ref-xml              Generate the VTY reference XML output and exit.\n");
-}
-
-static void handle_long_options(const char *prog_name, const int long_option)
-{
-	static int vty_ref_mode = VTY_REF_GEN_MODE_DEFAULT;
-
-	switch (long_option) {
-	case 1:
-		vty_ref_mode = get_string_value(vty_ref_gen_mode_names, optarg);
-		if (vty_ref_mode < 0) {
-			fprintf(stderr, "%s: Unknown VTY reference generation "
-				"mode '%s'\n", prog_name, optarg);
-			exit(2);
-		}
-		break;
-	case 2:
-		fprintf(stderr, "Generating the VTY reference in mode '%s' (%s)\n",
-			get_value_string(vty_ref_gen_mode_names, vty_ref_mode),
-			get_value_string(vty_ref_gen_mode_desc, vty_ref_mode));
-		vty_dump_xml_ref_mode(stdout, (enum vty_ref_gen_mode) vty_ref_mode);
-		exit(0);
-	default:
-		fprintf(stderr, "%s: error parsing cmdline options\n", prog_name);
-		exit(2);
-	}
-}
-
-static void handle_options(int argc, char **argv)
-{
-	while (1) {
-		int option_index = 0, c;
-		static int long_option = 0;
-		static struct option long_options[] = {
-			{"help", 0, 0, 'h'},
-			{"debug", 1, 0, 'd'},
-			{"daemonize", 0, 0, 'D'},
-			{"config-file", 1, 0, 'c'},
-			{"disable-color", 0, 0, 's'},
-			{"timestamp", 0, 0, 'T'},
-			{"version", 0, 0, 'V' },
-			{"log-level", 1, 0, 'e'},
-			{"vty-ref-mode", 1, &long_option, 1},
-			{"vty-ref-xml", 0, &long_option, 2},
-			{0, 0, 0, 0}
-		};
-
-		c = getopt_long(argc, argv, "hd:Dc:sTVe:",
-				long_options, &option_index);
-		if (c == -1)
-			break;
-
-		switch (c) {
-		case 0:
-			handle_long_options(argv[0], long_option);
-			break;
-		case 'h':
-			print_usage();
-			print_help();
-			exit(0);
-		case 's':
-			hnbgw_cmdline_config.log_disable_color = true;
-			break;
-		case 'd':
-			hnbgw_cmdline_config.log_category_mask = optarg;
-			break;
-		case 'D':
-			hnbgw_cmdline_config.daemonize = 1;
-			break;
-		case 'c':
-			hnbgw_cmdline_config.config_file = optarg;
-			break;
-		case 'T':
-			hnbgw_cmdline_config.log_enable_timestamp = true;
-			break;
-		case 'e':
-			hnbgw_cmdline_config.log_level = atoi(optarg);
-			break;
-		case 'V':
-			print_version(1);
-			exit(0);
-			break;
-		default:
-			/* catch unknown options *as well as* missing arguments. */
-			fprintf(stderr, "Error in command line options. Exiting.\n");
-			exit(-1);
-			break;
-		}
-	}
-
-	if (argc > optind) {
-		fprintf(stderr, "Unsupported positional arguments on command line\n");
-		exit(2);
-	}
-}
-
-CTRL_CMD_DEFINE_RO(hnb_info, "info");
-static int get_hnb_info(struct ctrl_cmd *cmd, void *data)
-{
-	struct hnb_context *hnb = data;
-
-	cmd->reply = talloc_strdup(cmd, hnb->identity_info);
-
-	return CTRL_CMD_REPLY;
-}
-
-CTRL_CMD_DEFINE_RO(hnbs, "num-hnb");
-static int get_hnbs(struct ctrl_cmd *cmd, void *data)
-{
-	cmd->reply = talloc_asprintf(cmd, "%u", hnb_contexts(data));
-
-	return CTRL_CMD_REPLY;
-}
-
-int hnb_ctrl_cmds_install()
-{
-	int rc = 0;
-
-	rc |= ctrl_cmd_install(CTRL_NODE_ROOT, &cmd_hnbs);
-	rc |= ctrl_cmd_install(CTRL_NODE_HNB, &cmd_hnb_info);
-
-	return rc;
-}
-
-static int hnb_ctrl_node_lookup(void *data, vector vline, int *node_type, void **node_data, int *i)
-{
-	const char *token = vector_slot(vline, *i);
-	struct hnb_context *hnb;
-	long num;
-
-	switch (*node_type) {
-	case CTRL_NODE_ROOT:
-		if (strcmp(token, "hnb") != 0)
-			return 0;
-
-		(*i)++;
-
-		if (!ctrl_parse_get_num(vline, *i, &num))
-			return -ERANGE;
-
-		hnb = hnb_context_by_id(data, num);
-		if (!hnb)
-			return -ENODEV;
-
-		*node_data = hnb;
-		*node_type = CTRL_NODE_HNB;
-		break;
-	default:
-		return 0;
-	}
-
-	return 1;
-}
-
-int main(int argc, char **argv)
-{
-	struct osmo_stream_srv_link *srv;
-	int rc;
-
-	tall_hnb_ctx = talloc_named_const(NULL, 0, "hnb_context");
-	talloc_asn1_ctx = talloc_named_const(NULL, 1, "asn1_context");
-	msgb_talloc_ctx_init(tall_hnb_ctx, 0);
-
-	g_hnb_gw = hnb_gw_create(tall_hnb_ctx);
-	g_hnb_gw->config.rnc_id = 23;
-
-	rc = osmo_init_logging2(tall_hnb_ctx, &hnbgw_log_info);
-	if (rc < 0)
-		exit(1);
-
-	rc = osmo_ss7_init();
-	if (rc < 0) {
-		LOGP(DMAIN, LOGL_FATAL, "osmo_ss7_init() failed with rc=%d\n", rc);
-		exit(1);
-	}
-
-	vty_info.copyright = osmo_hnbgw_copyright;
-	vty_init(&vty_info);
-
-	osmo_ss7_vty_init_asp(tall_hnb_ctx);
-	osmo_sccp_vty_init();
-	hnbgw_vty_init(g_hnb_gw, tall_hnb_ctx);
-	ctrl_vty_init(tall_hnb_ctx);
-	logging_vty_add_cmds();
-
-	/* Handle options after vty_init(), for --version */
-	handle_options(argc, argv);
-
-	rc = vty_read_config_file(hnbgw_cmdline_config.config_file, NULL);
-	if (rc < 0) {
-		LOGP(DMAIN, LOGL_FATAL, "Failed to parse the config file: '%s'\n",
-		     hnbgw_cmdline_config.config_file);
-		return 1;
-	}
-
-	/*
-	 * cmdline options take precedence over config file, but if no options
-	 * were passed we must not override the config file.
-	 */
-	if (hnbgw_cmdline_config.log_disable_color)
-		log_set_use_color(osmo_stderr_target, 0);
-	if (hnbgw_cmdline_config.log_category_mask)
-		log_parse_category_mask(osmo_stderr_target,
-					hnbgw_cmdline_config.log_category_mask);
-	if (hnbgw_cmdline_config.log_enable_timestamp)
-		log_set_print_timestamp(osmo_stderr_target, 1);
-	if (hnbgw_cmdline_config.log_level)
-		log_set_log_level(osmo_stderr_target,
-				  hnbgw_cmdline_config.log_level);
-
-	rc = telnet_init_dynif(tall_hnb_ctx, g_hnb_gw, vty_get_bind_addr(), OSMO_VTY_PORT_HNBGW);
-	if (rc < 0) {
-		perror("Error binding VTY port");
-		exit(1);
-	}
-
-	g_hnb_gw->ctrl = ctrl_interface_setup_dynip2(g_hnb_gw, ctrl_vty_get_bind_addr(), OSMO_CTRL_PORT_HNBGW,
-						     hnb_ctrl_node_lookup, _LAST_CTRL_NODE_HNB);
-	if (!g_hnb_gw->ctrl) {
-		LOGP(DMAIN, LOGL_ERROR, "Failed to create CTRL interface on %s:%u\n",
-		     ctrl_vty_get_bind_addr(), OSMO_CTRL_PORT_HNBGW);
-		exit(1);
-	} else {
-		rc = hnb_ctrl_cmds_install();
-		if (rc) {
-			LOGP(DMAIN, LOGL_ERROR, "Failed to install CTRL interface commands\n");
-			return 2;
-		}
-	}
-
-	ranap_set_log_area(DRANAP);
-
-	rc = hnbgw_cnlink_init(g_hnb_gw, "localhost", M3UA_PORT, "localhost");
-	if (rc < 0) {
-		LOGP(DMAIN, LOGL_ERROR, "Failed to initialize SCCP link to CN\n");
-		exit(1);
-	}
-
-	LOGP(DHNBAP, LOGL_NOTICE, "Using RNC-Id %u\n", g_hnb_gw->config.rnc_id);
-
-	OSMO_ASSERT(g_hnb_gw->config.iuh_local_ip);
-	LOGP(DMAIN, LOGL_NOTICE, "Listening for Iuh at %s %d\n",
-	     g_hnb_gw->config.iuh_local_ip,
-	     g_hnb_gw->config.iuh_local_port);
-	srv = osmo_stream_srv_link_create(tall_hnb_ctx);
-	if (!srv) {
-		perror("cannot create server");
-		exit(1);
-	}
-	osmo_stream_srv_link_set_data(srv, g_hnb_gw);
-	osmo_stream_srv_link_set_proto(srv, IPPROTO_SCTP);
-	osmo_stream_srv_link_set_nodelay(srv, true);
-	osmo_stream_srv_link_set_addr(srv, g_hnb_gw->config.iuh_local_ip);
-	osmo_stream_srv_link_set_port(srv, g_hnb_gw->config.iuh_local_port);
-	osmo_stream_srv_link_set_accept_cb(srv, accept_cb);
-
-	if (osmo_stream_srv_link_open(srv) < 0) {
-		perror("Cannot open server");
-		exit(1);
-	}
-	g_hnb_gw->iuh = srv;
-
-	if (hnbgw_cmdline_config.daemonize) {
-		rc = osmo_daemonize();
-		if (rc < 0) {
-			perror("Error during daemonize");
-			exit(1);
-		}
-	}
-
-	while (1) {
-		rc = osmo_select_main(0);
-		if (rc < 0)
-			exit(3);
-	}
-
-	/* not reached */
-	exit(0);
+	OSMO_ASSERT(!g_hnbgw);
+	g_hnbgw = talloc_zero(ctx, struct hnbgw);
+
+	/* strdup so we can easily talloc_free in the VTY code */
+	g_hnbgw->config.iuh_local_ip = talloc_strdup(g_hnbgw, HNBGW_LOCAL_IP_DEFAULT);
+	g_hnbgw->config.iuh_local_port = IUH_DEFAULT_SCTP_PORT;
+	g_hnbgw->config.hnbap_allow_tmsi = true;
+	g_hnbgw->config.log_prefix_hnb_id = true;
+	g_hnbgw->config.accept_all_hnb = true;
+
+	/* Set zero PLMN to detect a missing PLMN when transmitting RESET */
+	g_hnbgw->config.plmn = (struct osmo_plmn_id){ 0, 0, false };
+
+	g_hnbgw->next_ue_ctx_id = 23;
+	INIT_LLIST_HEAD(&g_hnbgw->hnb_list);
+
+	INIT_LLIST_HEAD(&g_hnbgw->hnb_persistent_list);
+	hash_init(g_hnbgw->hnb_persistent_by_id);
+
+	INIT_LLIST_HEAD(&g_hnbgw->sccp.users);
+
+	g_hnbgw->mgw_pool = mgcp_client_pool_alloc(g_hnbgw);
+	g_hnbgw->config.mgcp_client = mgcp_client_conf_alloc(g_hnbgw);
+
+#if ENABLE_PFCP
+	g_hnbgw->config.pfcp.remote_port = OSMO_PFCP_PORT;
+#endif
+
+	g_hnbgw->sccp.cnpool_iucs = hnbgw_cnpool_alloc(DOMAIN_CS);
+	g_hnbgw->sccp.cnpool_iups = hnbgw_cnpool_alloc(DOMAIN_PS);
+
+	osmo_timer_setup(&g_hnbgw->store_uptime_timer, hnbgw_store_hnb_uptime, g_hnbgw);
+	osmo_timer_schedule(&g_hnbgw->store_uptime_timer, STORE_UPTIME_INTERVAL, 0);
+
+	osmo_timer_setup(&g_hnbgw->hnb_store_rab_durations_timer, hnbgw_store_hnb_rab_durations, g_hnbgw);
+	osmo_timer_schedule(&g_hnbgw->hnb_store_rab_durations_timer, HNB_STORE_RAB_DURATIONS_INTERVAL, 0);
 }

src/osmo-hnbgw/hnbgw_cn.c

@@ -18,542 +18,313 @@
  *
  */
 
+#include "config.h"
+
 #include <arpa/inet.h>
 #include <errno.h>
 
+#include <asn1c/asn1helpers.h>
+
 #include <osmocom/core/msgb.h>
 #include <osmocom/core/utils.h>
-#include <osmocom/core/timer.h>
+#include <osmocom/core/stats.h>
+
+#include <osmocom/gsm/gsm23236.h>
 
 #include <osmocom/sigtran/protocol/m3ua.h>
+#include <osmocom/sigtran/protocol/sua.h>
 #include <osmocom/sigtran/sccp_sap.h>
 #include <osmocom/sigtran/sccp_helpers.h>
 
 #include <osmocom/hnbgw/hnbgw.h>
-#include <osmocom/hnbgw/hnbgw_rua.h>
-#include <osmocom/ranap/ranap_ies_defs.h>
-#include <osmocom/ranap/ranap_msg_factory.h>
+#include <osmocom/hnbgw/hnbgw_sccp.h>
+#include <osmocom/hnbgw/hnbgw_ranap.h>
+#include <osmocom/hnbgw/hnbgw_cn.h>
 #include <osmocom/hnbgw/context_map.h>
 
-/***********************************************************************
- * Outbound RANAP RESET to CN
- ***********************************************************************/
-
-void hnbgw_cnlink_change_state(struct hnbgw_cnlink *cnlink, enum hnbgw_cnlink_state state);
-
-static int transmit_rst(struct hnb_gw *gw, RANAP_CN_DomainIndicator_t domain,
-			struct osmo_sccp_addr *remote_addr)
+void hnbgw_cnpool_apply_cfg(struct hnbgw_cnpool *cnpool)
 {
-	struct msgb *msg;
-	RANAP_Cause_t cause = {
-		.present = RANAP_Cause_PR_transmissionNetwork,
-		.choice. transmissionNetwork = RANAP_CauseTransmissionNetwork_signalling_transport_resource_failure,
-	};
+	struct osmo_nri_range *r;
 
-	LOGP(DRANAP, LOGL_NOTICE, "Tx RESET to %s %s\n",
-	     domain == RANAP_CN_DomainIndicator_cs_domain ? "IuCS" : "IuPS",
-	     osmo_sccp_inst_addr_name(gw->sccp.cnlink->sccp, remote_addr));
+	cnpool->use.nri_bitlen = cnpool->vty.nri_bitlen;
 
-	msg = ranap_new_msg_reset(domain, &cause);
-
-	return osmo_sccp_tx_unitdata_msg(gw->sccp.cnlink->sccp_user,
-					 &gw->sccp.local_addr,
-					 remote_addr,
-					 msg);
+	osmo_nri_ranges_free(cnpool->use.null_nri_ranges);
+	cnpool->use.null_nri_ranges = osmo_nri_ranges_alloc(cnpool);
+	llist_for_each_entry(r, &cnpool->vty.null_nri_ranges->entries, entry)
+		osmo_nri_ranges_add(cnpool->use.null_nri_ranges, r);
 }
 
-static int transmit_reset_ack(struct hnb_gw *gw, RANAP_CN_DomainIndicator_t domain,
-			      const struct osmo_sccp_addr *remote_addr)
+void hnbgw_cnpool_cnlinks_start_or_restart(struct hnbgw_cnpool *cnpool)
 {
-	struct msgb *msg;
-
-	LOGP(DRANAP, LOGL_NOTICE, "Tx RESET ACK to %s %s\n",
-	     domain == RANAP_CN_DomainIndicator_cs_domain ? "IuCS" : "IuPS",
-	     osmo_sccp_inst_addr_name(gw->sccp.cnlink->sccp, remote_addr));
-
-	msg = ranap_new_msg_reset_ack(domain, NULL);
-
-	return osmo_sccp_tx_unitdata_msg(gw->sccp.cnlink->sccp_user,
-					 &gw->sccp.local_addr,
-					 remote_addr,
-					 msg);
-}
-
-/* Timer callback once T_RafC expires */
-static void cnlink_trafc_cb(void *data)
-{
-	struct hnb_gw *gw = data;
-
-	transmit_rst(gw, RANAP_CN_DomainIndicator_cs_domain, &gw->sccp.iucs_remote_addr);
-	transmit_rst(gw, RANAP_CN_DomainIndicator_ps_domain, &gw->sccp.iups_remote_addr);
-	hnbgw_cnlink_change_state(gw->sccp.cnlink, CNLINK_S_EST_RST_TX_WAIT_ACK);
-	/* The spec states that we should abandon after a configurable
-	 * number of times.  We decide to simply continue trying */
-}
-
-/* change the state of a CN Link */
-void hnbgw_cnlink_change_state(struct hnbgw_cnlink *cnlink, enum hnbgw_cnlink_state state)
-{
-	switch (state) {
-	case CNLINK_S_NULL:
-	case CNLINK_S_EST_PEND:
-		break;
-	case CNLINK_S_EST_CONF:
-		cnlink_trafc_cb(cnlink->gw);
-		break;
-	case CNLINK_S_EST_RST_TX_WAIT_ACK:
-		osmo_timer_schedule(&cnlink->T_RafC, 5, 0);
-		break;
-	case CNLINK_S_EST_ACTIVE:
-		osmo_timer_del(&cnlink->T_RafC);
-		break;
-	}
-}
-
-/***********************************************************************
- * Incoming primitives from SCCP User SAP
- ***********************************************************************/
-
-static int cn_ranap_rx_reset_cmd(struct hnbgw_cnlink *cnlink,
-				 const struct osmo_scu_unitdata_param *unitdata,
-				 RANAP_InitiatingMessage_t *imsg)
-{
-	RANAP_CN_DomainIndicator_t domain;
-	RANAP_ResetIEs_t ies;
-	int rc;
-
-	rc = ranap_decode_reseties(&ies, &imsg->value);
-	domain = ies.cN_DomainIndicator;
-	ranap_free_reseties(&ies);
-
-	LOGP(DRANAP, LOGL_NOTICE, "Rx RESET from %s %s, returning ACK\n",
-	     domain == RANAP_CN_DomainIndicator_cs_domain ? "IuCS" : "IuPS",
-	     osmo_sccp_inst_addr_name(cnlink->sccp, &unitdata->calling_addr));
-
-	/* FIXME: actually reset connections, if any */
-
-	if (transmit_reset_ack(cnlink->gw, domain, &unitdata->calling_addr))
-		LOGP(DRANAP, LOGL_ERROR, "Error: cannot send RESET ACK to %s %s\n",
-		     domain == RANAP_CN_DomainIndicator_cs_domain ? "IuCS" : "IuPS",
-		     osmo_sccp_inst_addr_name(cnlink->sccp, &unitdata->calling_addr));
-
-	return rc;
-}
-
-static int cn_ranap_rx_reset_ack(struct hnbgw_cnlink *cnlink,
-				 RANAP_SuccessfulOutcome_t *omsg)
-{
-	RANAP_ResetAcknowledgeIEs_t ies;
-	int rc;
-
-	rc = ranap_decode_resetacknowledgeies(&ies, &omsg->value);
-
-	hnbgw_cnlink_change_state(cnlink, CNLINK_S_EST_ACTIVE);
-
-	ranap_free_resetacknowledgeies(&ies);
-	return rc;
-}
-
-static int cn_ranap_rx_paging_cmd(struct hnbgw_cnlink *cnlink,
-				  RANAP_InitiatingMessage_t *imsg,
-				  const uint8_t *data, unsigned int len)
-{
-	struct hnb_gw *gw = cnlink->gw;
-	struct hnb_context *hnb;
-	RANAP_PagingIEs_t ies;
-	int rc;
-
-	rc = ranap_decode_pagingies(&ies, &imsg->value);
-	if (rc < 0)
-		return rc;
-
-	/* FIXME: determine which HNBs to send this Paging command,
-	 * rather than broadcasting to all HNBs */
-	llist_for_each_entry(hnb, &gw->hnb_list, list) {
-		rc = rua_tx_udt(hnb, data, len);
-	}
-
-	ranap_free_pagingies(&ies);
-	return 0;
-}
-
-static int cn_ranap_rx_initiating_msg(struct hnbgw_cnlink *cnlink,
-				      const struct osmo_scu_unitdata_param *unitdata,
-				      RANAP_InitiatingMessage_t *imsg,
-				      const uint8_t *data, unsigned int len)
-{
-	switch (imsg->procedureCode) {
-	case RANAP_ProcedureCode_id_Reset:
-		return cn_ranap_rx_reset_cmd(cnlink, unitdata, imsg);
-	case RANAP_ProcedureCode_id_Paging:
-		return cn_ranap_rx_paging_cmd(cnlink, imsg, data, len);
-	case RANAP_ProcedureCode_id_OverloadControl: /* Overload ind */
-		break;
-	case RANAP_ProcedureCode_id_ErrorIndication: /* Error ind */
-		break;
-	case RANAP_ProcedureCode_id_ResetResource: /* request */
-	case RANAP_ProcedureCode_id_InformationTransfer:
-	case RANAP_ProcedureCode_id_DirectInformationTransfer:
-	case RANAP_ProcedureCode_id_UplinkInformationExchange:
-		LOGP(DRANAP, LOGL_NOTICE, "Received unsupported RANAP "
-		     "Procedure %ld from CN, ignoring\n", imsg->procedureCode);
-		break;
-	default:
-		LOGP(DRANAP, LOGL_NOTICE, "Received suspicious RANAP "
-		     "Procedure %ld from CN, ignoring\n", imsg->procedureCode);
-		break;
-	}
-	return 0;
-}
-
-static int cn_ranap_rx_successful_msg(struct hnbgw_cnlink *cnlink,
-					RANAP_SuccessfulOutcome_t *omsg)
-{
-	switch (omsg->procedureCode) {
-	case RANAP_ProcedureCode_id_Reset: /* Reset acknowledge */
-		return cn_ranap_rx_reset_ack(cnlink, omsg);
-	case RANAP_ProcedureCode_id_ResetResource: /* response */
-	case RANAP_ProcedureCode_id_InformationTransfer:
-	case RANAP_ProcedureCode_id_DirectInformationTransfer:
-	case RANAP_ProcedureCode_id_UplinkInformationExchange:
-		LOGP(DRANAP, LOGL_NOTICE, "Received unsupported RANAP "
-		     "Procedure %ld from CN, ignoring\n", omsg->procedureCode);
-		break;
-	default:
-		LOGP(DRANAP, LOGL_NOTICE, "Received suspicious RANAP "
-		     "Procedure %ld from CN, ignoring\n", omsg->procedureCode);
-		break;
-	}
-	return 0;
-}
-
-
-static int _cn_ranap_rx(struct hnbgw_cnlink *cnlink,
-			const struct osmo_scu_unitdata_param *unitdata,
-			RANAP_RANAP_PDU_t *pdu, const uint8_t *data, unsigned int len)
-{
-	int rc;
-
-	switch (pdu->present) {
-	case RANAP_RANAP_PDU_PR_initiatingMessage:
-		rc = cn_ranap_rx_initiating_msg(cnlink, unitdata, &pdu->choice.initiatingMessage,
-						data, len);
-		break;
-	case RANAP_RANAP_PDU_PR_successfulOutcome:
-		rc = cn_ranap_rx_successful_msg(cnlink, &pdu->choice.successfulOutcome);
-		break;
-	case RANAP_RANAP_PDU_PR_unsuccessfulOutcome:
-		LOGP(DRANAP, LOGL_NOTICE, "Received unsupported RANAP "
-		     "unsuccessful outcome procedure %ld from CN, ignoring\n",
-		     pdu->choice.unsuccessfulOutcome.procedureCode);
-		rc = -ENOTSUP;
-		break;
-	default:
-		LOGP(DRANAP, LOGL_NOTICE, "Received suspicious RANAP "
-		     "presence %u from CN, ignoring\n", pdu->present);
-		rc = -EINVAL;
-		break;
-	}
-
-	return rc;
-}
-
-static int handle_cn_ranap(struct hnbgw_cnlink *cnlink, const struct osmo_scu_unitdata_param *unitdata,
-			   const uint8_t *data, unsigned int len)
-{
-	RANAP_RANAP_PDU_t _pdu, *pdu = &_pdu;
-	asn_dec_rval_t dec_ret;
-	int rc;
-
-	memset(pdu, 0, sizeof(*pdu));
-	dec_ret = aper_decode(NULL,&asn_DEF_RANAP_RANAP_PDU, (void **) &pdu,
-			      data, len, 0, 0);
-	if (dec_ret.code != RC_OK) {
-		LOGP(DRANAP, LOGL_ERROR, "Error in RANAP ASN.1 decode\n");
-		return -1;
-	}
-
-	rc = _cn_ranap_rx(cnlink, unitdata, pdu, data, len);
-
-	return rc;
-}
-
-static bool pc_and_ssn_match(const struct osmo_sccp_addr *a, const struct osmo_sccp_addr *b)
-{
-	return (a == b)
-	       || ((a->pc == b->pc)
-		   && (a->ssn == b->ssn));
-}
-
-static int classify_cn_remote_addr(const struct hnb_gw *gw,
-				   const struct osmo_sccp_addr *cn_remote_addr,
-				   bool *is_ps)
-{
-	if (pc_and_ssn_match(cn_remote_addr, &gw->sccp.iucs_remote_addr)) {
-		if (is_ps)
-			*is_ps = false;
-		return 0;
-	}
-	if (pc_and_ssn_match(cn_remote_addr, &gw->sccp.iups_remote_addr)) {
-		if (is_ps)
-			*is_ps = true;
-		return 0;
-	}
-	LOGP(DMAIN, LOGL_ERROR, "Unexpected remote address, matches neither CS nor PS address: %s\n",
-	     osmo_sccp_addr_dump(cn_remote_addr));
-	return -1;
-}
-
-static int handle_cn_unitdata(struct hnbgw_cnlink *cnlink,
-			      const struct osmo_scu_unitdata_param *param,
-			      struct osmo_prim_hdr *oph)
-{
-	if (param->called_addr.ssn != OSMO_SCCP_SSN_RANAP) {
-		LOGP(DMAIN, LOGL_NOTICE, "N-UNITDATA.ind for unknown SSN %u\n",
-			param->called_addr.ssn);
-		return -1;
-	}
-
-	if (classify_cn_remote_addr(cnlink->gw, &param->calling_addr, NULL) < 0)
-		return -1;
-
-	return handle_cn_ranap(cnlink, param, msgb_l2(oph->msg), msgb_l2len(oph->msg));
-}
-
-static int handle_cn_conn_conf(struct hnbgw_cnlink *cnlink,
-			       const struct osmo_scu_connect_param *param,
-			       struct osmo_prim_hdr *oph)
-{
-	/* we don't actually need to do anything, as RUA towards the HNB
-	 * doesn't seem to know any confirmations to its CONNECT
-	 * operation */
-
-	LOGP(DMAIN, LOGL_DEBUG, "handle_cn_conn_conf() conn_id=%d\n",
-	     param->conn_id);
-	LOGP(DMAIN, LOGL_DEBUG, "handle_cn_conn_conf() called_addr=%s\n",
-	     inet_ntoa(param->called_addr.ip.v4));
-	LOGP(DMAIN, LOGL_DEBUG, "handle_cn_conn_conf() calling_addr=%s\n",
-	     inet_ntoa(param->calling_addr.ip.v4));
-	LOGP(DMAIN, LOGL_DEBUG, "handle_cn_conn_conf() responding_addr=%s\n",
-	     inet_ntoa(param->responding_addr.ip.v4));
-
-	return 0;
-}
-
-static int handle_cn_data_ind(struct hnbgw_cnlink *cnlink,
-			      const struct osmo_scu_data_param *param,
-			      struct osmo_prim_hdr *oph)
-{
-	struct hnbgw_context_map *map;
-
-	/* connection-oriented data is always passed transparently
-	 * towards the specific HNB, via a RUA connection identified by
-	 * conn_id */
-
-	map = context_map_by_cn(cnlink, param->conn_id);
-	if (!map) {
-		/* FIXME: Return an error / released primitive */
-		return 0;
-	}
-
-	return rua_tx_dt(map->hnb_ctx, map->is_ps, map->rua_ctx_id,
-			 msgb_l2(oph->msg), msgb_l2len(oph->msg));
-}
-
-static int handle_cn_disc_ind(struct hnbgw_cnlink *cnlink,
-			      const struct osmo_scu_disconn_param *param,
-			      struct osmo_prim_hdr *oph)
-{
-	struct hnbgw_context_map *map;
-
-	LOGP(DMAIN, LOGL_DEBUG, "handle_cn_disc_ind() conn_id=%d originator=%d\n",
-	     param->conn_id, param->originator);
-	LOGP(DMAIN, LOGL_DEBUG, "handle_cn_disc_ind() responding_addr=%s\n",
-	     inet_ntoa(param->responding_addr.ip.v4));
-
-	RUA_Cause_t rua_cause = {
-		.present = RUA_Cause_PR_NOTHING,
-		/* FIXME: Convert incoming SCCP cause to RUA cause */
-	};
-
-	/* we need to notify the HNB associated with this connection via
-	 * a RUA DISCONNECT */
-
-	map = context_map_by_cn(cnlink, param->conn_id);
-	if (!map) {
-		/* FIXME: Return an error / released primitive */
-		return 0;
-	}
-
-	return rua_tx_disc(map->hnb_ctx, map->is_ps, map->rua_ctx_id,
-			   &rua_cause, msgb_l2(oph->msg), msgb_l2len(oph->msg));
-}
-
-/* Entry point for primitives coming up from SCCP User SAP */
-static int sccp_sap_up(struct osmo_prim_hdr *oph, void *ctx)
-{
-	struct osmo_sccp_user *scu = ctx;
 	struct hnbgw_cnlink *cnlink;
-	struct osmo_scu_prim *prim = (struct osmo_scu_prim *) oph;
-	int rc = 0;
-
-	LOGP(DMAIN, LOGL_DEBUG, "sccp_sap_up(%s)\n", osmo_scu_prim_name(oph));
-
-	if (!scu) {
-		LOGP(DMAIN, LOGL_ERROR,
-		     "sccp_sap_up(): NULL osmo_sccp_user, cannot send prim (sap %u prim %u op %d)\n",
-		     oph->sap, oph->primitive, oph->operation);
-		return -1;
+	hnbgw_cnpool_apply_cfg(cnpool);
+	llist_for_each_entry(cnlink, &cnpool->cnlinks, entry) {
+		hnbgw_cnlink_start_or_restart(cnlink);
 	}
-
-	cnlink = osmo_sccp_user_get_priv(scu);
-	if (!cnlink) {
-		LOGP(DMAIN, LOGL_ERROR,
-		     "sccp_sap_up(): NULL hnbgw_cnlink, cannot send prim (sap %u prim %u op %d)\n",
-		     oph->sap, oph->primitive, oph->operation);
-		return -1;
-	}
-
-	switch (OSMO_PRIM_HDR(oph)) {
-	case OSMO_PRIM(OSMO_SCU_PRIM_N_UNITDATA, PRIM_OP_INDICATION):
-		rc = handle_cn_unitdata(cnlink, &prim->u.unitdata, oph);
-		break;
-	case OSMO_PRIM(OSMO_SCU_PRIM_N_CONNECT, PRIM_OP_CONFIRM):
-		rc = handle_cn_conn_conf(cnlink, &prim->u.connect, oph);
-		break;
-	case OSMO_PRIM(OSMO_SCU_PRIM_N_DATA, PRIM_OP_INDICATION):
-		rc = handle_cn_data_ind(cnlink, &prim->u.data, oph);
-		break;
-	case OSMO_PRIM(OSMO_SCU_PRIM_N_DISCONNECT, PRIM_OP_INDICATION):
-		rc = handle_cn_disc_ind(cnlink, &prim->u.disconnect, oph);
-		break;
-	default:
-		LOGP(DMAIN, LOGL_ERROR,
-			"Received unknown prim %u from SCCP USER SAP\n",
-			OSMO_PRIM_HDR(oph));
-		break;
-	}
-
-	msgb_free(oph->msg);
-
-	return rc;
 }
 
-static bool addr_has_pc_and_ssn(const struct osmo_sccp_addr *addr)
+void hnbgw_cnpool_start(struct hnbgw_cnpool *cnpool)
 {
-	if (!(addr->presence & OSMO_SCCP_ADDR_T_SSN))
+	/* Legacy compat: when there is no 'msc N' at all in the config file, set up 'msc 0' with default values (or
+	 * 'sgsn' depending on cnpool). */
+	if (llist_empty(&cnpool->cnlinks))
+		cnlink_get_nr(cnpool, 0, true);
+	hnbgw_cnpool_cnlinks_start_or_restart(cnpool);
+}
+
+struct hnbgw_cnlink *cnlink_get_nr(struct hnbgw_cnpool *cnpool, int nr, bool create_if_missing)
+{
+	struct hnbgw_cnlink *cnlink;
+	llist_for_each_entry(cnlink, &cnpool->cnlinks, entry) {
+		if (cnlink->nr == nr)
+			return cnlink;
+	}
+
+	if (!create_if_missing)
+		return NULL;
+
+	return hnbgw_cnlink_alloc(cnpool, nr);
+}
+
+static bool is_cnlink_usable(struct hnbgw_cnlink *cnlink, bool is_emerg)
+{
+	if (is_emerg && !cnlink->allow_emerg)
 		return false;
-	if (!(addr->presence & OSMO_SCCP_ADDR_T_PC))
+	if (!cnlink->hnbgw_sccp_user || !cnlink->hnbgw_sccp_user->sccp_user)
+		return false;
+	if (!cnlink_is_conn_ready(cnlink))
 		return false;
 	return true;
 }
 
-static int resolve_addr_name(struct osmo_sccp_addr *dest, struct osmo_ss7_instance **ss7,
-			     const char *addr_name, const char *label,
-			     uint32_t default_pc)
+/* Decide which MSC/SGSN to forward this Complete Layer 3 request to. The current Layer 3 Info is passed in map->l3.
+ * a) If the subscriber was previously paged from a particular CN link, that CN link shall receive the Paging Response.
+ * b) If the message contains an NRI indicating a particular CN link that is currently connected, that CN link shall
+ *    handle this conn.
+ * c) All other cases distribute the messages across connected CN links in a round-robin fashion.
+ */
+struct hnbgw_cnlink *hnbgw_cnlink_select(struct hnbgw_context_map *map)
 {
-	struct osmo_ss7_instance *ss7_tmp;
+	struct hnbgw_cnpool *cnpool = map->is_ps ? g_hnbgw->sccp.cnpool_iups : g_hnbgw->sccp.cnpool_iucs;
+	struct hnbgw_cnlink *cnlink;
+	struct hnbgw_cnlink *round_robin_next = NULL;
+	struct hnbgw_cnlink *round_robin_first = NULL;
+	unsigned int round_robin_next_nr;
+	int16_t nri_v = -1;
+	bool is_null_nri = false;
+	uint8_t nri_bitlen = cnpool->use.nri_bitlen;
 
-	if (!addr_name) {
-		osmo_sccp_make_addr_pc_ssn(dest, default_pc, OSMO_SCCP_SSN_RANAP);
-		LOGP(DMAIN, LOGL_INFO, "%s remote addr not configured, using default: %s\n", label,
-		     osmo_sccp_addr_name(*ss7, dest));
-		return 0;
+	/* Match IMSI with previous Paging */
+	if (map->l3.gsm48_msg_type == GSM48_MT_RR_PAG_RESP) {
+		cnlink = cnlink_find_by_paging_mi(cnpool, &map->l3.mi);
+		if (cnlink) {
+			LOG_MAP(map, DCN, LOGL_INFO, "CN link paging response record selects %s %d\n", cnpool->peer_name,
+				cnlink->nr);
+			CNLINK_CTR_INC(cnlink, CNLINK_CTR_CNPOOL_SUBSCR_PAGED);
+			return cnlink;
+		}
+		LOG_MAP(map, DCN, LOGL_INFO, "CN link paging response didn't match any record on %s\n", cnpool->peer_name);
+		/* If there is no match, go on with other ways */
 	}
 
-	ss7_tmp = osmo_sccp_addr_by_name(dest, addr_name);
-	if (!ss7_tmp) {
-		LOGP(DMAIN, LOGL_ERROR, "%s remote addr: no such SCCP address book entry: '%s'\n",
-			label, addr_name);
-		return -1;
+#define LOG_NRI(LOGLEVEL, FORMAT, ARGS...) \
+	LOG_MAP(map, DCN, LOGLEVEL, "%s NRI(%dbit)=0x%x=%d: " FORMAT, osmo_mobile_identity_to_str_c(OTC_SELECT, &map->l3.mi), \
+		nri_bitlen, nri_v, nri_v, ##ARGS)
+
+	/* Get the NRI bits either from map->l3.nri, or extract NRI bits from TMSI.
+	 * The NRI possibly indicates which MSC is responsible. */
+	if (map->l3.gmm_nri_container >= 0) {
+		nri_v = map->l3.gmm_nri_container;
+		/* The 'TMSI based NRI container' is always 10 bits long. If the relevant NRI length is configured to be
+		 * less than that, ignore the lower bits. */
+		if (nri_bitlen < 10)
+			nri_v >>= 10 - nri_bitlen;
+	} else if (map->l3.mi.type == GSM_MI_TYPE_TMSI) {
+		if (osmo_tmsi_nri_v_get(&nri_v, map->l3.mi.tmsi, nri_bitlen)) {
+			LOG_NRI(LOGL_ERROR, "Unable to retrieve NRI from TMSI 0x%x, nri_bitlen == %u\n", map->l3.mi.tmsi,
+				nri_bitlen);
+			nri_v = -1;
+		}
 	}
 
-	if (*ss7 && (*ss7 != ss7_tmp)) {
-		LOGP(DMAIN, LOGL_ERROR, "IuCS and IuPS cannot be served from separate CS7 instances,"
-		     " cs7 instance %d != %d\n", (*ss7)->cfg.id, ss7_tmp->cfg.id);
-		return -1;
+	if (map->l3.from_other_plmn && nri_v >= 0) {
+		/* If a subscriber was previously attached to a different PLMN, it might still send the other
+		 * PLMN's TMSI identity in an IMSI Attach. The LU sends a LAI indicating the previous PLMN. If
+		 * it mismatches our PLMN, ignore the NRI. */
+		LOG_NRI(LOGL_DEBUG,
+			"This Complete Layer 3 message indicates a switch from another PLMN. Ignoring the NRI.\n");
+		nri_v = -1;
 	}
 
-	*ss7 = ss7_tmp;
+	if (nri_v >= 0)
+		is_null_nri = osmo_nri_v_matches_ranges(nri_v, cnpool->use.null_nri_ranges);
+	if (is_null_nri)
+		LOG_NRI(LOGL_DEBUG, "this is a NULL-NRI\n");
 
-	osmo_sccp_addr_set_ssn(dest, OSMO_SCCP_SSN_RANAP);
+	/* Iterate CN links to find one that matches the extracted NRI, and the next round-robin target for the case no
+	 * NRI match is found. */
+	round_robin_next_nr = (map->l3.is_emerg ? cnpool->round_robin_next_emerg_nr : cnpool->round_robin_next_nr);
+	llist_for_each_entry(cnlink, &cnpool->cnlinks, entry) {
+		bool nri_matches_cnlink = (nri_v >= 0 && osmo_nri_v_matches_ranges(nri_v, cnlink->use.nri_ranges));
 
-	if (!addr_has_pc_and_ssn(dest)) {
-		LOGP(DMAIN, LOGL_ERROR, "Invalid/incomplete %s remote-addr: %s\n",
-		     label, osmo_sccp_addr_name(*ss7, dest));
-		return -1;
+		if (!is_cnlink_usable(cnlink, map->l3.is_emerg)) {
+			if (nri_matches_cnlink) {
+				LOG_NRI(LOGL_DEBUG, "NRI matches %s %d, but this %s is currently not connected\n",
+					cnpool->peer_name, cnlink->nr, cnpool->peer_name);
+				CNLINK_CTR_INC(cnlink, CNLINK_CTR_CNPOOL_SUBSCR_ATTACH_LOST);
+			}
+			continue;
+		}
+
+		/* Return CN link if it matches this NRI, with some debug logging. */
+		if (nri_matches_cnlink) {
+			if (is_null_nri) {
+				LOG_NRI(LOGL_DEBUG, "NRI matches %s %d, but this NRI is also configured as NULL-NRI\n",
+					cnpool->peer_name, cnlink->nr);
+			} else {
+				LOG_NRI(LOGL_INFO, "NRI match selects %s %d\n", cnpool->peer_name, cnlink->nr);
+				CNLINK_CTR_INC(cnlink, CNLINK_CTR_CNPOOL_SUBSCR_KNOWN);
+				if (map->l3.is_emerg) {
+					CNLINK_CTR_INC(cnlink, CNLINK_CTR_CNPOOL_EMERG_FORWARDED);
+					CNPOOL_CTR_INC(cnpool, CNPOOL_CTR_EMERG_FORWARDED);
+				}
+				return cnlink;
+			}
+		}
+
+		/* Figure out the next round-robin MSC. The MSCs may appear unsorted in net->mscs. Make sure to linearly
+		 * round robin the MSCs by number: pick the lowest msc->nr >= round_robin_next_nr, and also remember the
+		 * lowest available msc->nr to wrap back to that in case no next MSC is left.
+		 *
+		 * MSCs configured with `no allow-attach` do not accept new subscribers and hence must not be picked by
+		 * round-robin. Such an MSC still provides service for already attached subscribers: those that
+		 * successfully performed IMSI-Attach and have a TMSI with an NRI pointing at that MSC. We only avoid
+		 * adding IMSI-Attach of new subscribers. The idea is that the MSC is in a mode of off-loading
+		 * subscribers, and the MSC decides when each subscriber is off-loaded, by assigning the NULL-NRI in a
+		 * new TMSI (at the next periodical LU). So until the MSC decides to offload, an attached subscriber
+		 * remains attached to that MSC and is free to use its services.
+		 */
+		if (!cnlink->allow_attach)
+			continue;
+		/* Find the allowed cnlink with the lowest nr */
+		if (!round_robin_first || cnlink->nr < round_robin_first->nr)
+			round_robin_first = cnlink;
+		/* Find the allowed cnlink with the lowest nr >= round_robin_next_nr */
+		if (cnlink->nr >= round_robin_next_nr
+		    && (!round_robin_next || cnlink->nr < round_robin_next->nr))
+			round_robin_next = cnlink;
 	}
 
-	LOGP(DRANAP, LOGL_NOTICE, "Remote %s SCCP addr: %s\n",
-	     label, osmo_sccp_addr_name(*ss7, dest));
-	return 0;
+	if (nri_v >= 0 && !is_null_nri)
+		LOG_NRI(LOGL_DEBUG, "No %s found for this NRI, doing round-robin\n", cnpool->peer_name);
+
+	/* No dedicated CN link found. Choose by round-robin.
+	 * If round_robin_next is NULL, there are either no more CN links at/after round_robin_next_nr, or none of
+	 * them are usable -- wrap to the start. */
+	cnlink = round_robin_next ? : round_robin_first;
+	if (!cnlink) {
+		CNPOOL_CTR_INC(cnpool, CNPOOL_CTR_SUBSCR_NO_CNLINK);
+		if (map->l3.is_emerg)
+			CNPOOL_CTR_INC(cnpool, CNPOOL_CTR_EMERG_LOST);
+		return NULL;
+	}
+
+	LOG_MAP(map, DCN, LOGL_INFO, "CN link round-robin selects %s %d\n", cnpool->peer_name, cnlink->nr);
+
+	if (is_null_nri)
+		CNLINK_CTR_INC(cnlink, CNLINK_CTR_CNPOOL_SUBSCR_REATTACH);
+	else
+		CNLINK_CTR_INC(cnlink, CNLINK_CTR_CNPOOL_SUBSCR_NEW);
+
+	if (map->l3.is_emerg) {
+		CNLINK_CTR_INC(cnlink, CNLINK_CTR_CNPOOL_EMERG_FORWARDED);
+		CNPOOL_CTR_INC(cnpool, CNPOOL_CTR_EMERG_FORWARDED);
+	}
+
+	/* A CN link was picked by round-robin, so update the next round-robin nr to pick */
+	if (map->l3.is_emerg)
+		cnpool->round_robin_next_emerg_nr = cnlink->nr + 1;
+	else
+		cnpool->round_robin_next_nr = cnlink->nr + 1;
+	return cnlink;
+#undef LOG_NRI
 }
 
-int hnbgw_cnlink_init(struct hnb_gw *gw, const char *stp_host, uint16_t stp_port, const char *local_ip)
+static const struct rate_ctr_desc cnpool_ctr_description[] = {
+	[CNPOOL_CTR_SUBSCR_NO_CNLINK] = {
+		"cnpool:subscr:no_cnlink",
+		"Complete Layer 3 requests lost because no connected CN link is found available",
+	},
+	[CNPOOL_CTR_EMERG_FORWARDED] = {
+		"cnpool:emerg:forwarded",
+		"Emergency call requests forwarded to a CN link (see also per-CN-link counters)",
+	},
+	[CNPOOL_CTR_EMERG_LOST] = {
+		"cnpool:emerg:lost",
+		"Emergency call requests lost because no CN link was found available",
+	},
+};
+
+const struct rate_ctr_group_desc iucs_ctrg_desc = {
+	"iucs",
+	"IuCS",
+	OSMO_STATS_CLASS_GLOBAL,
+	ARRAY_SIZE(cnpool_ctr_description),
+	cnpool_ctr_description,
+};
+
+const struct rate_ctr_group_desc iups_ctrg_desc = {
+	"iups",
+	"IuPS",
+	OSMO_STATS_CLASS_GLOBAL,
+	ARRAY_SIZE(cnpool_ctr_description),
+	cnpool_ctr_description,
+};
+
+static int hnbgw_cnpool_talloc_destructor(struct hnbgw_cnpool *cnpool)
 {
 	struct hnbgw_cnlink *cnlink;
-	struct osmo_ss7_instance *ss7;
-	uint32_t local_pc;
-
-	OSMO_ASSERT(!gw->sccp.client);
-	OSMO_ASSERT(!gw->sccp.cnlink);
-
-	ss7 = NULL;
-	if (resolve_addr_name(&gw->sccp.iucs_remote_addr, &ss7,
-			      gw->config.iucs_remote_addr_name, "IuCS", (23 << 3) + 1))
-		return -1;
-	if (resolve_addr_name(&gw->sccp.iups_remote_addr, &ss7,
-			      gw->config.iups_remote_addr_name, "IuPS", (23 << 3) + 4))
-		return -1;
-
-	if (!ss7) {
-		LOGP(DRANAP, LOGL_NOTICE, "No cs7 instance configured for IuCS nor IuPS,"
-		     " creating default instance\n");
-		ss7 = osmo_ss7_instance_find_or_create(gw, 0);
-		ss7->cfg.primary_pc = (23 << 3) + 5;
-	}
-
-	if (!osmo_ss7_pc_is_valid(ss7->cfg.primary_pc)) {
-		LOGP(DMAIN, LOGL_ERROR, "IuCS/IuPS uplink cannot be setup: CS7 instance %d has no point-code set\n",
-		     ss7->cfg.id);
-		return -1;
-	}
-	local_pc = ss7->cfg.primary_pc;
-
-	osmo_sccp_make_addr_pc_ssn(&gw->sccp.local_addr, local_pc, OSMO_SCCP_SSN_RANAP);
-	LOGP(DRANAP, LOGL_NOTICE, "Local SCCP addr: %s\n", osmo_sccp_addr_name(ss7, &gw->sccp.local_addr));
-
-	gw->sccp.client = osmo_sccp_simple_client_on_ss7_id(gw, ss7->cfg.id, "OsmoHNBGW",
-							    local_pc, OSMO_SS7_ASP_PROT_M3UA,
-							    0, local_ip, stp_port, stp_host);
-	if (!gw->sccp.client) {
-		LOGP(DMAIN, LOGL_ERROR, "Failed to init SCCP Client\n");
-		return -1;
-	}
-
-	cnlink = talloc_zero(gw, struct hnbgw_cnlink);
-	cnlink->gw = gw;
-	INIT_LLIST_HEAD(&cnlink->map_list);
-	cnlink->T_RafC.cb = cnlink_trafc_cb;
-	cnlink->T_RafC.data = gw;
-	cnlink->next_conn_id = 1000;
-
-	cnlink->sccp_user = osmo_sccp_user_bind_pc(gw->sccp.client, "OsmoHNBGW", sccp_sap_up,
-						   OSMO_SCCP_SSN_RANAP, gw->sccp.local_addr.pc);
-	if (!cnlink->sccp_user) {
-		LOGP(DMAIN, LOGL_ERROR, "Failed to init SCCP User\n");
-		return -1;
-	}
-
-	LOGP(DRANAP, LOGL_NOTICE, "Remote SCCP addr: IuCS: %s\n",
-	     osmo_sccp_addr_name(ss7, &gw->sccp.iucs_remote_addr));
-	LOGP(DRANAP, LOGL_NOTICE, "Remote SCCP addr: IuPS: %s\n",
-	     osmo_sccp_addr_name(ss7, &gw->sccp.iups_remote_addr));
-
-	/* In sccp_sap_up() we expect the cnlink in the user's priv. */
-	osmo_sccp_user_set_priv(cnlink->sccp_user, cnlink);
-
-	gw->sccp.cnlink = cnlink;
+	osmo_nri_ranges_free(cnpool->vty.null_nri_ranges);
+	cnpool->vty.null_nri_ranges = NULL;
 
+	while ((cnlink = llist_first_entry_or_null(&cnpool->cnlinks, struct hnbgw_cnlink, entry)))
+		hnbgw_cnlink_term_and_free(cnlink);
 	return 0;
 }
+
+struct hnbgw_cnpool *hnbgw_cnpool_alloc(RANAP_CN_DomainIndicator_t domain)
+{
+	struct hnbgw_cnpool *cnpool = talloc_zero(g_hnbgw, struct hnbgw_cnpool);
+	OSMO_ASSERT(cnpool);
+
+	cnpool->domain = domain;
+	cnpool->vty = (struct hnbgw_cnpool_cfg){
+		.nri_bitlen = OSMO_NRI_BITLEN_DEFAULT,
+		.null_nri_ranges = osmo_nri_ranges_alloc(cnpool),
+	};
+	OSMO_ASSERT(cnpool->vty.null_nri_ranges);
+	INIT_LLIST_HEAD(&cnpool->cnlinks);
+
+	talloc_set_destructor(cnpool, hnbgw_cnpool_talloc_destructor);
+
+	switch (domain) {
+	case DOMAIN_CS:
+		cnpool->pool_name = "iucs";
+		cnpool->peer_name = "msc";
+		cnpool->default_remote_pc = DEFAULT_PC_MSC;
+		cnpool->default_addr_name = DEFAULT_ADDR_NAME_MSC;
+		cnpool->ctrs = rate_ctr_group_alloc(cnpool, &iucs_ctrg_desc, 0);
+		break;
+	case DOMAIN_PS:
+		cnpool->pool_name = "iups";
+		cnpool->peer_name = "sgsn";
+		cnpool->default_remote_pc = DEFAULT_PC_SGSN;
+		cnpool->default_addr_name = DEFAULT_ADDR_NAME_SGSN;
+		cnpool->ctrs = rate_ctr_group_alloc(cnpool, &iups_ctrg_desc, 0);
+		break;
+	default:
+		OSMO_ASSERT(0);
+	}
+
+	return cnpool;
+}

src/osmo-hnbgw/hnbgw_hnbap.c

@@ -1,4 +1,4 @@
-/* hnb-gw specific code for HNBAP */
+/* hnb-gw specific code for HNBAP, 3GPP TS 25.469 */
 
 /* (C) 2015 by Harald Welte <laforge@gnumonks.org>
  * All Rights Reserved
@@ -22,6 +22,7 @@
 #include <osmocom/core/utils.h>
 #include <osmocom/core/socket.h>
 #include <osmocom/gsm/gsm48.h>
+#include <osmocom/gsm/protocol/gsm_23_003.h>
 #include <osmocom/netif/stream.h>
 
 #include <unistd.h>
@@ -32,6 +33,8 @@
 #include <osmocom/hnbap/hnbap_common.h>
 #include <osmocom/ranap/iu_helpers.h>
 
+#include <osmocom/hnbgw/hnb.h>
+#include <osmocom/hnbgw/hnb_persistent.h>
 #include <osmocom/hnbgw/hnbgw.h>
 #include <osmocom/hnbap/hnbap_ies_defs.h>
 
@@ -49,16 +52,61 @@ static int hnbgw_hnbap_tx(struct hnb_context *ctx, struct msgb *msg)
 	return 0;
 }
 
-static int hnbgw_tx_hnb_register_rej(struct hnb_context *ctx)
+static int hnbgw_tx_error_ind(struct hnb_context *ctx, const HNBAP_Cause_t *cause,
+			      HNBAP_ProcedureCode_t proc_code, HNBAP_Criticality_t criticality,
+			      HNBAP_TriggeringMessage_t trig_msg)
+{
+	HNBAP_ErrorIndication_t err_ind;
+	HNBAP_ErrorIndicationIEs_t err_ind_ies;
+	struct msgb *msg;
+	int rc;
+
+	LOGHNB(ctx, DHNBAP, LOGL_ERROR, "Tx ErrorIndication cause=%s\n", hnbap_cause_str(cause));
+
+	err_ind_ies.presenceMask = 0;
+	err_ind_ies.cause = *cause;
+
+	if (proc_code != -1 || trig_msg != -1 || criticality != -1) {
+		err_ind_ies.presenceMask |= ERRORINDICATIONIES_HNBAP_CRITICALITYDIAGNOSTICS_PRESENT;
+		if (proc_code != -1)
+			err_ind_ies.criticalityDiagnostics.procedureCode = &proc_code;
+		if (trig_msg != -1)
+			err_ind_ies.criticalityDiagnostics.triggeringMessage = &trig_msg;
+		if (criticality != -1)
+			err_ind_ies.criticalityDiagnostics.procedureCriticality = &criticality;
+	}
+
+	memset(&err_ind, 0, sizeof(err_ind));
+	rc = hnbap_encode_errorindicationies(&err_ind, &err_ind_ies);
+	if (rc < 0) {
+		LOGHNB(ctx, DHNBAP, LOGL_ERROR, "Failure to encode ERROR-INDICATION to %s: rc=%d\n",
+			ctx->identity_info, rc);
+		return rc;
+	}
+
+	msg = hnbap_generate_initiating_message(HNBAP_ProcedureCode_id_ErrorIndication,
+						HNBAP_Criticality_ignore,
+						&asn_DEF_HNBAP_ErrorIndication,
+						&err_ind);
+
+	ASN_STRUCT_FREE_CONTENTS_ONLY(asn_DEF_HNBAP_ErrorIndication, &err_ind);
+
+	return hnbgw_hnbap_tx(ctx, msg);
+}
+
+static int hnbgw_tx_hnb_register_rej(struct hnb_context *ctx, const HNBAP_Cause_t *cause)
 {
 	HNBAP_HNBRegisterReject_t reject_out;
 	HNBAP_HNBRegisterRejectIEs_t reject;
 	struct msgb *msg;
 	int rc;
 
-	reject.presenceMask = 0,
-	reject.cause.present = HNBAP_Cause_PR_radioNetwork;
-	reject.cause.choice.radioNetwork = HNBAP_CauseRadioNetwork_unspecified;
+	OSMO_ASSERT(cause);
+
+	LOGHNB(ctx, DHNBAP, LOGL_ERROR, "Rejecting HNB Register Request cause=%s\n", hnbap_cause_str(cause));
+
+	reject.presenceMask = 0;
+	reject.cause = *cause;
 
 	/* encode the Information Elements */
 	memset(&reject_out, 0, sizeof(reject_out));
@@ -69,7 +117,7 @@ static int hnbgw_tx_hnb_register_rej(struct hnb_context *ctx)
 		return rc;
 	}
 
-	/* generate a successfull outcome PDU */
+	/* generate a unsuccessful outcome PDU */
 	msg = hnbap_generate_unsuccessful_outcome(HNBAP_ProcedureCode_id_HNBRegister,
 						  HNBAP_Criticality_reject,
 						  &asn_DEF_HNBAP_HNBRegisterReject,
@@ -99,7 +147,7 @@ static int hnbgw_tx_hnb_register_acc(struct hnb_context *ctx)
 
 	/* Single required response IE: RNC-ID */
 	HNBAP_HNBRegisterAcceptIEs_t accept = {
-		.rnc_id = ctx->gw->config.rnc_id
+		.rnc_id = g_hnbgw->config.rnc_id
 	};
 
 	/* encode the Information Elements */
@@ -111,7 +159,7 @@ static int hnbgw_tx_hnb_register_acc(struct hnb_context *ctx)
 		return rc;
 	}
 
-	/* generate a successfull outcome PDU */
+	/* generate a successful outcome PDU */
 	msg = hnbap_generate_successful_outcome(HNBAP_ProcedureCode_id_HNBRegister,
 					       HNBAP_Criticality_reject,
 					       &asn_DEF_HNBAP_HNBRegisterAccept,
@@ -119,13 +167,13 @@ static int hnbgw_tx_hnb_register_acc(struct hnb_context *ctx)
 
 	ASN_STRUCT_FREE_CONTENTS_ONLY(asn_DEF_HNBAP_HNBRegisterAccept, &accept_out);
 
-	LOGHNB(ctx, DHNBAP, LOGL_NOTICE, "Accepting HNB-REGISTER-REQ from %s\n", ctx->identity_info);
+	LOGHNB(ctx, DHNBAP, LOGL_NOTICE, "Accepting HNB-REGISTER-REQ\n");
 
 	return hnbgw_hnbap_tx(ctx, msg);
 }
 
 
-static int hnbgw_tx_ue_register_acc(struct ue_context *ue)
+static int hnbgw_tx_ue_register_acc(struct hnb_context *hnb, const char *imsi, uint32_t context_id)
 {
 	HNBAP_UERegisterAccept_t accept_out;
 	HNBAP_UERegisterAcceptIEs_t accept;
@@ -136,17 +184,20 @@ static int hnbgw_tx_ue_register_acc(struct ue_context *ue)
 	int rc;
 
 	encoded_imsi_len = ranap_imsi_encode(encoded_imsi,
-					  sizeof(encoded_imsi), ue->imsi);
+					  sizeof(encoded_imsi), imsi);
 
 	memset(&accept, 0, sizeof(accept));
 	accept.uE_Identity.present = HNBAP_UE_Identity_PR_iMSI;
 	OCTET_STRING_fromBuf(&accept.uE_Identity.choice.iMSI,
 			     (const char *)encoded_imsi, encoded_imsi_len);
-	asn1_u24_to_bitstring(&accept.context_ID, &ctx_id, ue->context_id);
+	asn1_u24_to_bitstring(&accept.context_ID, &ctx_id, context_id);
 
 	memset(&accept_out, 0, sizeof(accept_out));
 	rc = hnbap_encode_ueregisteraccepties(&accept_out, &accept);
+	ASN_STRUCT_FREE_CONTENTS_ONLY(asn_DEF_OCTET_STRING, &accept.uE_Identity.choice.iMSI);
 	if (rc < 0) {
+		LOGHNB(hnb, DHNBAP, LOGL_ERROR,
+		       "Failed to encode HNBAP UE Register Accept message for UE IMSI-%s\n", imsi);
 		return rc;
 	}
 
@@ -155,19 +206,25 @@ static int hnbgw_tx_ue_register_acc(struct ue_context *ue)
 						&asn_DEF_HNBAP_UERegisterAccept,
 						&accept_out);
 
-	ASN_STRUCT_FREE_CONTENTS_ONLY(asn_DEF_OCTET_STRING, &accept.uE_Identity.choice.iMSI);
 	ASN_STRUCT_FREE_CONTENTS_ONLY(asn_DEF_HNBAP_UERegisterAccept, &accept_out);
 
-	return hnbgw_hnbap_tx(ue->hnb, msg);
+	rc = hnbgw_hnbap_tx(hnb, msg);
+	if (rc)
+		LOGHNB(hnb, DHNBAP, LOGL_ERROR,
+		       "Failed to enqueue HNBAP UE Register Accept message for UE IMSI-%s\n", imsi);
+	return rc;
 }
 
-static int hnbgw_tx_ue_register_rej_tmsi(struct hnb_context *hnb, HNBAP_UE_Identity_t *ue_id)
+static int hnbgw_tx_ue_register_rej(struct hnb_context *hnb, HNBAP_UE_Identity_t *ue_id, const struct HNBAP_Cause *cause)
 {
 	HNBAP_UERegisterReject_t reject_out;
 	HNBAP_UERegisterRejectIEs_t reject;
+	char imsi[GSM23003_IMSI_MAX_DIGITS+1];
 	struct msgb *msg;
 	int rc;
 
+	OSMO_ASSERT(cause);
+
 	memset(&reject, 0, sizeof(reject));
 	reject.uE_Identity.present = ue_id->present;
 
@@ -223,16 +280,23 @@ static int hnbgw_tx_ue_register_rej_tmsi(struct hnb_context *hnb, HNBAP_UE_Ident
 				     ue_id->choice.pTMSIRAI.rAI.rAC.size);
 		break;
 
+	case HNBAP_UE_Identity_PR_iMSI:
+		ranap_bcd_decode(imsi, sizeof(imsi), ue_id->choice.iMSI.buf, ue_id->choice.iMSI.size);
+		LOGHNB(hnb, DHNBAP, LOGL_DEBUG, "REJ UE_Id IMSI %s\n", imsi);
+
+		OCTET_STRING_fromBuf(&reject.uE_Identity.choice.iMSI,
+				     (const char *)ue_id->choice.iMSI.buf, ue_id->choice.iMSI.size);
+		break;
+
 	default:
 		LOGHNB(hnb, DHNBAP, LOGL_ERROR, "Cannot compose UE Register Reject:"
 		     " unsupported UE ID (present=%d)\n", ue_id->present);
 		return -1;
 	}
 
-	LOGHNB(hnb, DHNBAP, LOGL_ERROR, "Rejecting UE Register Request: TMSI identity registration is switched off\n");
+	LOGHNB(hnb, DHNBAP, LOGL_ERROR, "Rejecting UE Register Request cause=%s\n", hnbap_cause_str(cause));
 
-	reject.cause.present = HNBAP_Cause_PR_radioNetwork;
-	reject.cause.choice.radioNetwork = HNBAP_CauseRadioNetwork_invalid_UE_identity;
+	reject.cause = *cause;
 
 	memset(&reject_out, 0, sizeof(reject_out));
 	rc = hnbap_encode_ueregisterrejecties(&reject_out, &reject);
@@ -265,6 +329,9 @@ static int hnbgw_tx_ue_register_rej_tmsi(struct hnb_context *hnb, HNBAP_UE_Ident
 		ASN_STRUCT_FREE_CONTENTS_ONLY(asn_DEF_OCTET_STRING,
 					      &reject.uE_Identity.choice.pTMSIRAI.rAI.rAC);
 		break;
+	case HNBAP_UE_Identity_PR_iMSI:
+		ASN_STRUCT_FREE_CONTENTS_ONLY(asn_DEF_OCTET_STRING,
+					      &reject.uE_Identity.choice.iMSI);
 
 	default:
 		/* should never happen after above switch() */
@@ -276,14 +343,13 @@ static int hnbgw_tx_ue_register_rej_tmsi(struct hnb_context *hnb, HNBAP_UE_Ident
 	return hnbgw_hnbap_tx(hnb, msg);
 }
 
-static int hnbgw_tx_ue_register_acc_tmsi(struct hnb_context *hnb, HNBAP_UE_Identity_t *ue_id)
+static int hnbgw_tx_ue_register_acc_tmsi(struct hnb_context *hnb, HNBAP_UE_Identity_t *ue_id, uint32_t context_id)
 {
 	HNBAP_UERegisterAccept_t accept_out;
 	HNBAP_UERegisterAcceptIEs_t accept;
 	struct msgb *msg;
 	uint32_t ctx_id;
 	uint32_t tmsi = 0;
-	struct ue_context *ue;
 	int rc;
 
 	memset(&accept, 0, sizeof(accept));
@@ -322,29 +388,19 @@ static int hnbgw_tx_ue_register_acc_tmsi(struct hnb_context *hnb, HNBAP_UE_Ident
 		break;
 
 	default:
-		LOGHNB(hnb, DHNBAP, LOGL_ERROR, "Unsupportedccept UE ID (present=%d)\n", ue_id->present);
+		LOGHNB(hnb, DHNBAP, LOGL_ERROR, "Unsupported HNBAP UE Identity type (present=%d)\n", ue_id->present);
 		return -1;
 	}
 
 	tmsi = ntohl(tmsi);
 	LOGHNB(hnb, DHNBAP, LOGL_DEBUG, "HNBAP register with TMSI %x\n", tmsi);
 
-	ue = ue_context_by_tmsi(hnb->gw, tmsi);
-	if (!ue)
-		ue = ue_context_alloc(hnb, NULL, tmsi);
-
-	asn1_u24_to_bitstring(&accept.context_ID, &ctx_id, ue->context_id);
+	asn1_u24_to_bitstring(&accept.context_ID, &ctx_id, context_id);
 
 	memset(&accept_out, 0, sizeof(accept_out));
 	rc = hnbap_encode_ueregisteraccepties(&accept_out, &accept);
-	if (rc < 0)
-		return rc;
-
-	msg = hnbap_generate_successful_outcome(HNBAP_ProcedureCode_id_UERegister,
-						HNBAP_Criticality_reject,
-						&asn_DEF_HNBAP_UERegisterAccept,
-						&accept_out);
 
+	/* free 'accept', now encoded in 'accept_out' */
 	switch (ue_id->present) {
 	case HNBAP_UE_Identity_PR_tMSILAI:
 		ASN_STRUCT_FREE_CONTENTS_ONLY(asn_DEF_BIT_STRING,
@@ -371,65 +427,166 @@ static int hnbgw_tx_ue_register_acc_tmsi(struct hnb_context *hnb, HNBAP_UE_Ident
 		break;
 	}
 
-	ASN_STRUCT_FREE_CONTENTS_ONLY(asn_DEF_HNBAP_UERegisterAccept, &accept_out);
+	if (rc < 0) {
+		LOGHNB(hnb, DHNBAP, LOGL_ERROR, "Failed to encode HNBAP UE Register Accept for TMSI 0x%08x\n", tmsi);
+		/* Encoding failed. Nothing in 'accept_out'. */
+		return rc;
+	}
 
-	return hnbgw_hnbap_tx(hnb, msg);
+	/* Encoding successful, transmit, then free 'accept_out'. */
+	msg = hnbap_generate_successful_outcome(HNBAP_ProcedureCode_id_UERegister,
+						HNBAP_Criticality_reject,
+						&asn_DEF_HNBAP_UERegisterAccept,
+						&accept_out);
+	rc = hnbgw_hnbap_tx(hnb, msg);
+	ASN_STRUCT_FREE_CONTENTS_ONLY(asn_DEF_HNBAP_UERegisterAccept, &accept_out);
+	if (rc)
+		LOGHNB(hnb, DHNBAP, LOGL_ERROR, "Failed to transmit HNBAP UE Register Accept for TMSI 0x%08x\n", tmsi);
+	return rc;
 }
 
 static int hnbgw_rx_hnb_deregister(struct hnb_context *ctx, ANY_t *in)
 {
 	HNBAP_HNBDe_RegisterIEs_t ies;
+	HNBAP_Cause_t cause = {};
 	int rc;
 
 	rc = hnbap_decode_hnbde_registeries(&ies, in);
-	if (rc < 0)
-		return rc;
+	if (rc < 0) {
+		cause.present = HNBAP_Cause_PR_protocol;
+		cause.choice.radioNetwork = HNBAP_CauseProtocol_unspecified;
+		return hnbgw_tx_error_ind(ctx, &cause, HNBAP_ProcedureCode_id_HNBDe_Register, HNBAP_Criticality_ignore,
+					  HNBAP_TriggeringMessage_initiating_message);
+	}
 
 	LOGHNB(ctx, DHNBAP, LOGL_DEBUG, "HNB-DE-REGISTER cause=%s\n", hnbap_cause_str(&ies.cause));
 
 	hnbap_free_hnbde_registeries(&ies);
-	hnb_context_release(ctx);
+	ctx->hnb_registered = false;
 
 	return 0;
 }
 
+static bool is_asn1_octet_string_empty(const OCTET_STRING_t *val)
+{
+	return !val || !val->buf || !val->size;
+}
+
+static bool is_asn1_bit_string_empty(const BIT_STRING_t *val)
+{
+	return !val || !val->buf || !val->size;
+}
+
 static int hnbgw_rx_hnb_register_req(struct hnb_context *ctx, ANY_t *in)
 {
-	struct hnb_context *hnb;
+	struct hnb_persistent *hnbp;
+	struct hnb_context *hnb, *tmp;
 	HNBAP_HNBRegisterRequestIEs_t ies;
 	int rc;
+	struct osmo_fd *ofd = osmo_stream_srv_get_ofd(ctx->conn);
+	char identity_str[256];
+	const char *cell_id_str;
+	struct timespec tp;
+	HNBAP_Cause_t cause = {};
+	struct osmo_sockaddr cur_osa = {};
+	socklen_t len = sizeof(cur_osa);
 
 	rc = hnbap_decode_hnbregisterrequesties(&ies, in);
-	if (rc < 0) {
-		LOGHNB(ctx, DHNBAP, LOGL_ERROR, "Failure to decode HNB-REGISTER-REQ from %s: rc=%d\n",
-			ctx->identity_info, rc);
-		return rc;
+	if (rc < 0
+	    /* CID#465551: make sure that actual values ended up in the asn1 octet strings: */
+	    || is_asn1_octet_string_empty(&ies.lac)
+	    || is_asn1_octet_string_empty(&ies.sac)
+	    || is_asn1_octet_string_empty(&ies.rac)
+	    || is_asn1_bit_string_empty(&ies.cellIdentity)
+	    || is_asn1_octet_string_empty(&ies.plmNidentity)) {
+		LOGHNB(ctx, DHNBAP, LOGL_ERROR, "Failure to decode HNB-REGISTER-REQ: rc=%d\n", rc);
+		cause.present = HNBAP_Cause_PR_protocol;
+		cause.choice.radioNetwork = HNBAP_CauseProtocol_unspecified;
+		return hnbgw_tx_hnb_register_rej(ctx, &cause);
 	}
+	asn1_strncpy(identity_str, &ies.hnB_Identity.hNB_Identity_Info, sizeof(identity_str));
 
 	/* copy all identity parameters from the message to ctx */
-	asn1_strncpy(ctx->identity_info, &ies.hnB_Identity.hNB_Identity_Info,
-			sizeof(ctx->identity_info));
+	OSMO_STRLCPY_ARRAY(ctx->identity_info, identity_str);
+
+	/* We want to use struct umts_cell_id as hashtable key. If it ever happens to contain any padding bytes, make
+	 * sure everything is deterministically zero. */
+	memset(&ctx->id, 0, sizeof(ctx->id));
 	ctx->id.lac = asn1str_to_u16(&ies.lac);
 	ctx->id.sac = asn1str_to_u16(&ies.sac);
 	ctx->id.rac = asn1str_to_u8(&ies.rac);
 	ctx->id.cid = asn1bitstr_to_u28(&ies.cellIdentity);
-	gsm48_mcc_mnc_from_bcd(ies.plmNidentity.buf, &ctx->id.mcc, &ctx->id.mnc);
+	osmo_plmn_from_bcd(ies.plmNidentity.buf, &ctx->id.plmn);
+	cell_id_str = umts_cell_id_to_str(&ctx->id);
 
-	llist_for_each_entry(hnb, &ctx->gw->hnb_list, list) {
+	if (getpeername(ofd->fd, &cur_osa.u.sa, &len) < 0) {
+		LOGHNB(ctx, DHNBAP, LOGL_ERROR, "HNB-REGISTER-REQ %s: rejecting due to getpeername() error: %s\n",
+		       cell_id_str, strerror(errno));
+		hnbap_free_hnbregisterrequesties(&ies);
+		cause.present = HNBAP_Cause_PR_radioNetwork;
+		cause.choice.radioNetwork = HNBAP_CauseRadioNetwork_hNB_parameter_mismatch;
+		return hnbgw_tx_hnb_register_rej(ctx, &cause);
+	}
+
+	hnbp = hnb_persistent_find_by_id(&ctx->id);
+	if (!hnbp && g_hnbgw->config.accept_all_hnb)
+		hnbp = hnb_persistent_alloc(&ctx->id);
+
+	if (!hnbp) {
+		LOGHNB(ctx, DHNBAP, LOGL_NOTICE, "Rejecting unknonwn HNB with identity %s\n", identity_str);
+		hnbap_free_hnbregisterrequesties(&ies);
+		cause.present = HNBAP_Cause_PR_radioNetwork;
+		cause.choice.radioNetwork = HNBAP_CauseRadioNetwork_unauthorised_HNB;
+		return hnbgw_tx_hnb_register_rej(ctx, &cause);
+	}
+
+	ctx->persistent = hnbp;
+	hnbp->ctx = ctx;
+
+	HNBP_CTR_INC(hnbp, HNB_CTR_IUH_ESTABLISHED);
+	rc = osmo_clock_gettime(CLOCK_MONOTONIC, &tp);
+	hnbp->updowntime = (rc < 0) ? 0 : tp.tv_sec;
+
+	llist_for_each_entry_safe(hnb, tmp, &g_hnbgw->hnb_list, list) {
 		if (hnb->hnb_registered && ctx != hnb && memcmp(&ctx->id, &hnb->id, sizeof(ctx->id)) == 0) {
-			struct osmo_fd *ofd = osmo_stream_srv_get_ofd(ctx->conn);
-			char *name = osmo_sock_get_name(ctx, ofd->fd);
-			LOGHNB(ctx, DHNBAP, LOGL_ERROR, "rejecting HNB-REGISTER-REQ with duplicate cell identity "
-				"MCC=%u,MNC=%u,LAC=%u,RAC=%u,SAC=%u,CID=%u from %s\n",
-				ctx->id.mcc, ctx->id.mnc, ctx->id.lac, ctx->id.rac, ctx->id.sac, ctx->id.cid, name);
-			talloc_free(name);
-			return hnbgw_tx_hnb_register_rej(ctx);
+			/* If it's coming from the same remote IP addr+port, then it must be our internal
+			 * fault (bug), and we release the old context to keep going... */
+			struct osmo_fd *other_fd = osmo_stream_srv_get_ofd(hnb->conn);
+			struct osmo_sockaddr other_osa = {};
+			socklen_t len = sizeof(other_osa);
+			if (getpeername(other_fd->fd, &other_osa.u.sa, &len) < 0) {
+				LOGHNB(ctx, DHNBAP, LOGL_ERROR, "BUG! Found old registered HNB with invalid socket, releasing it\n");
+				hnb_context_release(hnb);
+				continue;
+			}
+			if (osmo_sockaddr_cmp(&cur_osa, &other_osa) == 0) {
+				LOGHNB(ctx, DHNBAP, LOGL_ERROR, "BUG! Found old registered HNB with same remote address, releasing it\n");
+				hnb_context_release(hnb);
+				continue;
+			} /* else: addresses are different, we continue below */
+
+			/* If new conn registering same HNB is from anoter remote addr+port, let's reject it to avoid
+			 * misconfigurations or someone trying to impersonate an already working HNB: */
+			LOGHNB(ctx, DHNBAP, LOGL_ERROR, "rejecting HNB-REGISTER-REQ with duplicate cell identity %s\n", cell_id_str);
+			hnbap_free_hnbregisterrequesties(&ies);
+			cause.present = HNBAP_Cause_PR_radioNetwork;
+			cause.choice.radioNetwork = HNBAP_CauseRadioNetwork_hNB_parameter_mismatch;
+			return hnbgw_tx_hnb_register_rej(ctx, &cause);
 		}
 	}
 
+	LOGHNB(ctx, DHNBAP, LOGL_DEBUG, "HNB-REGISTER-REQ %s %s%s\n",
+	       ctx->identity_info, cell_id_str, ctx->hnb_registered ? " (re-connecting)" : "");
+
+	/* The HNB is already registered, and we are seeing a new HNB Register Request. The HNB has restarted
+	 * without us noticing. Clearly, the HNB does not expect any UE state to be active here, so discard any
+	 * UE contexts and SCCP connections associated with this HNB. */
+	LOGHNB(ctx, DHNBAP, LOGL_NOTICE, "HNB (re)connecting, discarding all previous UE state\n");
+	hnb_context_release_ue_state(ctx);
+
 	ctx->hnb_registered = true;
 
-	LOGHNB(ctx, DHNBAP, LOGL_DEBUG, "HNB-REGISTER-REQ from %s\n", ctx->identity_info);
+	hnb_persistent_registered(ctx->persistent);
 
 	/* Send HNBRegisterAccept */
 	rc = hnbgw_tx_hnb_register_acc(ctx);
@@ -440,13 +597,26 @@ static int hnbgw_rx_hnb_register_req(struct hnb_context *ctx, ANY_t *in)
 static int hnbgw_rx_ue_register_req(struct hnb_context *ctx, ANY_t *in)
 {
 	HNBAP_UERegisterRequestIEs_t ies;
-	struct ue_context *ue;
-	char imsi[16];
+	HNBAP_Cause_t cause = {};
+	char imsi[GSM23003_IMSI_MAX_DIGITS+1];
 	int rc;
 
 	rc = hnbap_decode_ueregisterrequesties(&ies, in);
-	if (rc < 0)
-		return rc;
+	if (rc < 0) {
+		LOGHNB(ctx, DHNBAP, LOGL_ERROR, "Failure to decode UE-REGISTER-REQ: rc=%d\n", rc);
+		cause.present = HNBAP_Cause_PR_protocol;
+		cause.choice.radioNetwork = HNBAP_CauseProtocol_unspecified;
+		return hnbgw_tx_error_ind(ctx, &cause, HNBAP_ProcedureCode_id_UERegister, HNBAP_Criticality_reject,
+					  HNBAP_TriggeringMessage_initiating_message);
+	}
+
+	if (!ctx->hnb_registered) {
+		/* UE registration requires prior HNB registration; reject with proper cause */
+		cause.present = HNBAP_Cause_PR_radioNetwork;
+		cause.choice.radioNetwork = HNBAP_CauseRadioNetwork_hNB_not_registered;
+		rc = hnbgw_tx_ue_register_rej(ctx, &ies.uE_Identity, &cause);
+		goto free_and_return_rc;
+	}
 
 	switch (ies.uE_Identity.present) {
 	case HNBAP_UE_Identity_PR_iMSI:
@@ -463,50 +633,63 @@ static int hnbgw_rx_ue_register_req(struct hnb_context *ctx, ANY_t *in)
 		break;
 	case HNBAP_UE_Identity_PR_tMSILAI:
 	case HNBAP_UE_Identity_PR_pTMSIRAI:
-		if (ctx->gw->config.hnbap_allow_tmsi)
-			rc = hnbgw_tx_ue_register_acc_tmsi(ctx, &ies.uE_Identity);
-		else
-			rc = hnbgw_tx_ue_register_rej_tmsi(ctx, &ies.uE_Identity);
+		if (g_hnbgw->config.hnbap_allow_tmsi) {
+			rc = hnbgw_tx_ue_register_acc_tmsi(ctx, &ies.uE_Identity, get_next_ue_ctx_id());
+		} else {
+			cause.present = HNBAP_Cause_PR_radioNetwork;
+			cause.choice.radioNetwork = HNBAP_CauseRadioNetwork_invalid_UE_identity;
+			rc = hnbgw_tx_ue_register_rej(ctx, &ies.uE_Identity, &cause);
+		}
 		/* all has been handled by TMSI, skip the IMSI code below */
-		hnbap_free_ueregisterrequesties(&ies);
-		return rc;
+		goto free_and_return_rc;
 	default:
 		LOGHNB(ctx, DHNBAP, LOGL_NOTICE, "UE-REGISTER-REQ with unsupported UE Id type %d\n",
 			ies.uE_Identity.present);
-		hnbap_free_ueregisterrequesties(&ies);
-		return rc;
+		cause.present = HNBAP_Cause_PR_radioNetwork;
+		cause.choice.radioNetwork = HNBAP_CauseRadioNetwork_invalid_UE_identity;
+		rc = hnbgw_tx_ue_register_rej(ctx, &ies.uE_Identity, &cause);
+		goto free_and_return_rc;
 	}
 
 	LOGHNB(ctx, DHNBAP, LOGL_DEBUG, "UE-REGISTER-REQ ID_type=%d imsi=%s cause=%ld\n",
 		ies.uE_Identity.present, imsi, ies.registration_Cause);
 
-	ue = ue_context_by_imsi(ctx->gw, imsi);
-	if (!ue)
-		ue = ue_context_alloc(ctx, imsi, 0);
-
-	hnbap_free_ueregisterrequesties(&ies);
 	/* Send UERegisterAccept */
-	return hnbgw_tx_ue_register_acc(ue);
+	rc = hnbgw_tx_ue_register_acc(ctx, imsi, get_next_ue_ctx_id());
+	if (rc < 0)
+		LOGHNB(ctx, DHNBAP, LOGL_ERROR, "Failed to transmit HNBAP UE Register Accept for IMSI %s\n", imsi);
+free_and_return_rc:
+	hnbap_free_ueregisterrequesties(&ies);
+	return rc;
 }
 
 static int hnbgw_rx_ue_deregister(struct hnb_context *ctx, ANY_t *in)
 {
 	HNBAP_UEDe_RegisterIEs_t ies;
-	struct ue_context *ue;
+	HNBAP_Cause_t cause = {};
 	int rc;
 	uint32_t ctxid;
 
 	rc = hnbap_decode_uede_registeries(&ies, in);
-	if (rc < 0)
-		return rc;
+	if (rc < 0) {
+		cause.present = HNBAP_Cause_PR_protocol;
+		cause.choice.protocol = HNBAP_CauseProtocol_unspecified;
+		return hnbgw_tx_error_ind(ctx, &cause, HNBAP_ProcedureCode_id_UEDe_Register,
+					  HNBAP_Criticality_ignore, HNBAP_TriggeringMessage_initiating_message);
+	}
 
 	ctxid = asn1bitstr_to_u24(&ies.context_ID);
 
-	LOGHNB(ctx, DHNBAP, LOGL_DEBUG, "UE-DE-REGISTER context=%u cause=%s\n", ctxid, hnbap_cause_str(&ies.cause));
-
-	ue = ue_context_by_id(ctx->gw, ctxid);
-	if (ue)
-		ue_context_free(ue);
+	if (!ctx->hnb_registered) {
+		LOGHNB(ctx, DHNBAP, LOGL_NOTICE, "UE-DE-REGISTER context=%u cause=%s not permitted; HNB not registered\n",
+			ctxid, hnbap_cause_str(&ies.cause));
+		cause.present = HNBAP_Cause_PR_radioNetwork;
+		cause.choice.radioNetwork = HNBAP_CauseRadioNetwork_hNB_not_registered;
+		hnbgw_tx_error_ind(ctx, &cause, HNBAP_ProcedureCode_id_UEDe_Register,
+				   HNBAP_Criticality_ignore, HNBAP_TriggeringMessage_initiating_message);
+	} else {
+		LOGHNB(ctx, DHNBAP, LOGL_DEBUG, "UE-DE-REGISTER context=%u cause=%s\n", ctxid, hnbap_cause_str(&ies.cause));
+	}
 
 	hnbap_free_uede_registeries(&ies);
 	return 0;
@@ -529,6 +712,10 @@ static int hnbgw_rx_err_ind(struct hnb_context *hnb, ANY_t *in)
 
 static int hnbgw_rx_initiating_msg(struct hnb_context *hnb, HNBAP_InitiatingMessage_t *imsg)
 {
+	HNBAP_Cause_t cause = {
+		.present = HNBAP_Cause_PR_protocol,
+		.choice.protocol = HNBAP_CauseProtocol_unspecified,
+	};
 	int rc = 0;
 
 	switch (imsg->procedureCode) {
@@ -538,7 +725,7 @@ static int hnbgw_rx_initiating_msg(struct hnb_context *hnb, HNBAP_InitiatingMess
 	case HNBAP_ProcedureCode_id_HNBDe_Register:	/* 8.3 */
 		rc = hnbgw_rx_hnb_deregister(hnb, &imsg->value);
 		break;
-	case HNBAP_ProcedureCode_id_UERegister: 	/* 8.4 */
+	case HNBAP_ProcedureCode_id_UERegister:		/* 8.4 */
 		rc = hnbgw_rx_ue_register_req(hnb, &imsg->value);
 		break;
 	case HNBAP_ProcedureCode_id_UEDe_Register:	/* 8.5 */
@@ -547,15 +734,17 @@ static int hnbgw_rx_initiating_msg(struct hnb_context *hnb, HNBAP_InitiatingMess
 	case HNBAP_ProcedureCode_id_ErrorIndication:	/* 8.6 */
 		rc = hnbgw_rx_err_ind(hnb, &imsg->value);
 		break;
-	case HNBAP_ProcedureCode_id_TNLUpdate:	/* 8.9 */
+	case HNBAP_ProcedureCode_id_TNLUpdate:		/* 8.9 */
 	case HNBAP_ProcedureCode_id_HNBConfigTransfer:	/* 8.10 */
 	case HNBAP_ProcedureCode_id_RelocationComplete:	/* 8.11 */
 	case HNBAP_ProcedureCode_id_U_RNTIQuery:	/* 8.12 */
 	case HNBAP_ProcedureCode_id_privateMessage:
 		LOGHNB(hnb, DHNBAP, LOGL_NOTICE, "Unimplemented HNBAP Procedure %ld\n", imsg->procedureCode);
+		rc = hnbgw_tx_error_ind(hnb, &cause, imsg->procedureCode, -1, HNBAP_TriggeringMessage_initiating_message);
 		break;
 	default:
 		LOGHNB(hnb, DHNBAP, LOGL_NOTICE, "Unknown HNBAP Procedure %ld\n", imsg->procedureCode);
+		rc = hnbgw_tx_error_ind(hnb, &cause, imsg->procedureCode, -1, HNBAP_TriggeringMessage_initiating_message);
 		break;
 	}
 
@@ -572,8 +761,7 @@ static int hnbgw_rx_unsuccessful_outcome_msg(struct hnb_context *hnb, HNBAP_Unsu
 {
 	/* We don't care much about HNBAP */
 	LOGHNB(hnb, DHNBAP, LOGL_ERROR, "Received Unsuccessful Outcome, procedureCode %ld, criticality %ld,"
-		" cell mcc %u mnc %u lac %u rac %u sac %u cid %u\n", msg->procedureCode, msg->criticality,
-		hnb->id.mcc, hnb->id.mnc, hnb->id.lac, hnb->id.rac, hnb->id.sac, hnb->id.cid);
+		" cell %s\n", msg->procedureCode, msg->criticality, umts_cell_id_to_str(&hnb->id));
 	return 0;
 }
 

src/osmo-hnbgw/hnbgw_l3.c

@@ -0,0 +1,331 @@
+/* OsmoHNBGW implementation of CS and PS Level3 message decoding (NAS PDU) */
+
+/* Copyright 2023 by sysmocom - s.f.m.c. GmbH <info@sysmocom.de>
+ * All Rights Reserved
+ *
+ * Author: Neels Janosch Hofmeyr <nhofmeyr@sysmocom.de>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include "config.h"
+
+#include "asn1helpers.h"
+
+#include <osmocom/gsm/gsm48.h>
+#include <osmocom/gsm/protocol/gsm_04_08_gprs.h>
+
+#include <osmocom/hnbgw/hnbgw.h>
+#include <osmocom/hnbgw/hnbgw_ranap.h>
+#include <osmocom/hnbgw/context_map.h>
+#include <osmocom/ranap/ranap_ies_defs.h>
+
+static const struct tlv_definition gsm48_gmm_att_tlvdef = {
+	.def = {
+		[GSM48_IE_GMM_CIPH_CKSN]	= { TLV_TYPE_FIXED, 1 },
+		[GSM48_IE_GMM_TIMER_READY]	= { TLV_TYPE_TV, 1 },
+		[GSM48_IE_GMM_TMSI_BASED_NRI_C]	= { TLV_TYPE_TLV },
+		[GSM48_IE_GMM_ALLOC_PTMSI]	= { TLV_TYPE_TLV, 0 },
+		[GSM48_IE_GMM_PTMSI_SIG]	= { TLV_TYPE_FIXED, 3 },
+		[GSM48_IE_GMM_AUTH_RAND]	= { TLV_TYPE_FIXED, 16 },
+		[GSM48_IE_GMM_AUTH_SRES]	= { TLV_TYPE_FIXED, 4 },
+		[GSM48_IE_GMM_IMEISV]		= { TLV_TYPE_TLV, 0 },
+		[GSM48_IE_GMM_DRX_PARAM]	= { TLV_TYPE_FIXED, 2 },
+		[GSM48_IE_GMM_MS_NET_CAPA]	= { TLV_TYPE_TLV, 0 },
+		[GSM48_IE_GMM_PDP_CTX_STATUS]	= { TLV_TYPE_TLV, 0 },
+		[GSM48_IE_GMM_PS_LCS_CAPA]	= { TLV_TYPE_TLV, 0 },
+		[GSM48_IE_GMM_GMM_MBMS_CTX_ST]	= { TLV_TYPE_TLV, 0 },
+	},
+};
+
+static void decode_gmm_tlv(struct osmo_mobile_identity *mi, int *nri,
+			   const uint8_t *tlv_data, size_t tlv_len, bool allow_hex)
+{
+	struct tlv_parsed tp;
+	struct tlv_p_entry *e;
+
+	tlv_parse(&tp, &gsm48_gmm_att_tlvdef, tlv_data, tlv_len, 0, 0);
+
+	e = TLVP_GET(&tp, GSM48_IE_GMM_TMSI_BASED_NRI_C);
+	if (e) {
+		*nri = e->val[0];
+		*nri <<= 2;
+		*nri |= e->val[1] >> 6;
+	}
+
+	/* RAU Req: 9.4.14.5 P-TMSI (Iu mode only): "This IE shall be included by the MS." */
+	e = TLVP_GET(&tp, GSM48_IE_GMM_ALLOC_PTMSI);
+	if (mi && e)
+		osmo_mobile_identity_decode(mi, e->val, e->len, allow_hex);
+}
+
+/* Parse 3GPP TS 24.008 § 9.4.1 Attach request */
+static int mobile_identity_decode_from_gmm_att_req(struct osmo_mobile_identity *mi,
+						   struct osmo_routing_area_id *old_ra,
+						   int *nri,
+						   const uint8_t *l3_data, size_t l3_len, bool allow_hex)
+{
+	const struct gsm48_hdr *gh = (void *)l3_data;
+	const uint8_t *cur = gh->data;
+	const uint8_t *end = l3_data + l3_len;
+	const uint8_t *mi_data;
+	uint8_t mi_len;
+	uint8_t msnc_len;
+	uint8_t ms_ra_acc_cap_len;
+	int rc;
+
+	if (l3_len < 26)
+		return -ENOSPC;
+
+	/* MS network capability 10.5.5.12 */
+	msnc_len = *cur++;
+	if (l3_len < (msnc_len + (cur - l3_data)))
+		return -ENOSPC;
+	cur += msnc_len;
+
+	/* aTTACH Type 10.5.5.2 + Ciphering key sequence number 10.5.1.2 */
+	cur++;
+
+	/* DRX parameter 10.5.5.6 */
+	cur += 2;
+
+	/* Mobile Identity (P-TMSI or IMSI) 10.5.1.4 */
+	mi_len = *cur++;
+	mi_data = cur;
+	if (l3_len < (mi_len + (cur - l3_data)))
+		return -ENOSPC;
+	cur += mi_len;
+
+	rc = osmo_mobile_identity_decode(mi, mi_data, mi_len, allow_hex);
+	if (rc)
+		return rc;
+
+	/* Old routing area identification 10.5.5.15. */
+	rc = osmo_routing_area_id_decode(old_ra, cur, end - cur);
+	if (rc < 0)
+		return rc;
+	cur += rc;
+
+	/* MS Radio Access Capability 10.5.5.12a */
+	ms_ra_acc_cap_len = *cur++;
+	if (l3_len < (ms_ra_acc_cap_len + (cur - l3_data)))
+		return -ENOSPC;
+	cur += ms_ra_acc_cap_len;
+
+	if (l3_len == (cur - l3_data))
+		return 0; /* No Optional TLV section */
+
+	/* Mobile identity = NULL: already obtained from Mandatory IE above.*/
+	decode_gmm_tlv(NULL, nri, cur, end - cur, allow_hex);
+	return 0;
+}
+
+/* Parse 24.008 9.4.14 RAU Request */
+static int mobile_identity_decode_from_gmm_rau_req(struct osmo_mobile_identity *mi,
+						   struct osmo_routing_area_id *old_ra,
+						   int *nri,
+						   const uint8_t *l3_data, size_t l3_len, bool allow_hex)
+{
+	const struct gsm48_hdr *gh = (void *)l3_data;
+	const uint8_t *cur = gh->data;
+	const uint8_t *end = l3_data + l3_len;
+	uint8_t ms_ra_acc_cap_len;
+	int rc;
+
+	/* all mandatory fields + variable length MS Radio Cap (min value) would be 15 bytes.
+	 * But even short radio capabilities we should handle with 14 bytes */
+	if (l3_len < 14)
+		return -ENOSPC;
+
+	/* V: Update Type 10.5.5.18 */
+	cur++;
+
+	/* V: Old routing area identification 10.5.5.15 */
+	rc = osmo_routing_area_id_decode(old_ra, cur, end - cur);
+	if (rc < 0)
+		return rc;
+	cur += rc;
+	if (cur >= end)
+		return -ENOSPC;
+
+	/* LV: MS Radio Access Capability 10.5.5.12a */
+	ms_ra_acc_cap_len = *cur++;
+	if (l3_len < (ms_ra_acc_cap_len + (cur - l3_data)))
+		return -ENOSPC;
+	cur += ms_ra_acc_cap_len;
+
+	if (l3_len == (cur - l3_data))
+		return 0; /* No Optional TLV section */
+	decode_gmm_tlv(mi, nri, cur, end - cur, allow_hex);
+	return 0;
+}
+
+/* CS MM: Determine mobile identity, from_other_plmn, is_emerg. */
+static int peek_l3_ul_nas_cs(struct hnbgw_context_map *map, const uint8_t *nas_pdu, size_t len,
+			     const struct osmo_plmn_id *local_plmn)
+{
+	const struct gsm48_hdr *gh = (const struct gsm48_hdr *)nas_pdu;
+	struct osmo_location_area_id old_lai;
+	const struct gsm48_loc_upd_req *lu;
+	struct gsm48_service_request *cm;
+
+	osmo_mobile_identity_decode_from_l3_buf(&map->l3.mi, nas_pdu, len, false);
+
+	switch (map->l3.gsm48_pdisc) {
+	case GSM48_PDISC_MM:
+		/* Get is_emerg and from_other_plmn */
+		switch (map->l3.gsm48_msg_type) {
+		case GSM48_MT_MM_LOC_UPD_REQUEST:
+			if (len < sizeof(*gh) + sizeof(*lu)) {
+				LOGP(DCN, LOGL_ERROR, "LU Req message too short\n");
+				break;
+			}
+			lu = (struct gsm48_loc_upd_req *)gh->data;
+			gsm48_decode_lai2(&lu->lai, &old_lai);
+			map->l3.from_other_plmn = (osmo_plmn_cmp(&old_lai.plmn, local_plmn) != 0);
+			if (map->l3.from_other_plmn)
+				LOGP(DRUA, LOGL_INFO, "LU from other PLMN: old LAI=%s my PLMN=%s\n",
+				     osmo_plmn_name_c(OTC_SELECT, &old_lai.plmn),
+				     osmo_plmn_name_c(OTC_SELECT, local_plmn));
+			return 0;
+
+		case GSM48_MT_MM_CM_SERV_REQ:
+			if (len < sizeof(*gh) + sizeof(*cm)) {
+				LOGP(DRUA, LOGL_ERROR, "CM Service Req message too short\n");
+				break;
+			}
+			cm = (struct gsm48_service_request *)&gh->data[0];
+			map->l3.is_emerg = (cm->cm_service_type == GSM48_CMSERV_EMERGENCY);
+			LOGP(DRUA, LOGL_DEBUG, "CM Service is_emerg=%d\n", map->l3.is_emerg);
+			return 0;
+		}
+		break;
+	}
+
+	return 0;
+}
+
+/* PS GMM: Determine mobile identity, gmm_nri_container, from_other_plmn and is_emerg */
+static int peek_l3_ul_nas_ps(struct hnbgw_context_map *map, const uint8_t *nas_pdu, size_t len,
+			     const struct osmo_plmn_id *local_plmn)
+{
+	struct osmo_routing_area_id old_ra = {};
+	int nri = -1;
+
+	switch (map->l3.gsm48_pdisc) {
+	case GSM48_PDISC_MM_GPRS:
+		switch (map->l3.gsm48_msg_type) {
+		case GSM48_MT_GMM_ATTACH_REQ:
+			mobile_identity_decode_from_gmm_att_req(&map->l3.mi, &old_ra, &nri, nas_pdu, len, false);
+			LOGP(DRUA, LOGL_DEBUG, "GMM Attach Req mi=%s old_ra=%s nri:%d=0x%x\n",
+			     osmo_mobile_identity_to_str_c(OTC_SELECT, &map->l3.mi),
+			     osmo_rai_name2_c(OTC_SELECT, &old_ra),
+			     nri, nri);
+			if (old_ra.lac.plmn.mcc && osmo_plmn_cmp(&old_ra.lac.plmn, local_plmn)) {
+				map->l3.from_other_plmn = true;
+				LOGP(DRUA, LOGL_INFO, "GMM Attach Req from other PLMN: old RAI=%s my PLMN=%s\n",
+				     osmo_rai_name2_c(OTC_SELECT, &old_ra),
+				     osmo_plmn_name_c(OTC_SELECT, local_plmn));
+			}
+			if (nri >= 0)
+				map->l3.gmm_nri_container = nri;
+			return 0;
+
+		case GSM48_MT_GMM_RA_UPD_REQ:
+			mobile_identity_decode_from_gmm_rau_req(&map->l3.mi, &old_ra, &nri, nas_pdu, len, false);
+			LOGP(DRUA, LOGL_DEBUG, "GMM Routing Area Upd Req mi=%s old_ra=%s nri:%d=0x%x\n",
+			     osmo_mobile_identity_to_str_c(OTC_SELECT, &map->l3.mi),
+			     osmo_rai_name2_c(OTC_SELECT, &old_ra),
+			     nri, nri);
+			if (old_ra.lac.plmn.mcc && osmo_plmn_cmp(&old_ra.lac.plmn, local_plmn)) {
+				map->l3.from_other_plmn = true;
+				LOGP(DRUA, LOGL_INFO, "GMM Routing Area Upd Req from other PLMN: old RAI=%s my PLMN=%s\n",
+				     osmo_rai_name2_c(OTC_SELECT, &old_ra),
+				     osmo_plmn_name_c(OTC_SELECT, local_plmn));
+			}
+			if (nri >= 0)
+				map->l3.gmm_nri_container = nri;
+			return 0;
+		}
+		break;
+	}
+
+	return 0;
+}
+
+static int peek_l3_ul_nas(struct hnbgw_context_map *map, const uint8_t *nas_pdu, size_t len,
+			  const struct osmo_plmn_id *local_plmn)
+{
+	const struct gsm48_hdr *gh = (const struct gsm48_hdr *)nas_pdu;
+
+	map->l3 = (struct hnbgw_l3_peek){
+		.gmm_nri_container = -1,
+		.mi = {
+			.type = GSM_MI_TYPE_NONE,
+			.tmsi = GSM_RESERVED_TMSI,
+		},
+	};
+
+	if (len < sizeof(*gh)) {
+		LOGP(DCN, LOGL_ERROR, "Layer 3 message too short for header\n");
+		return -EINVAL;
+	}
+
+	map->l3.gsm48_pdisc = gsm48_hdr_pdisc(gh);
+	map->l3.gsm48_msg_type = gsm48_hdr_msg_type(gh);
+
+	if (map->is_ps)
+		return peek_l3_ul_nas_ps(map, nas_pdu, len, local_plmn);
+	return peek_l3_ul_nas_cs(map, nas_pdu, len, local_plmn);
+}
+
+static int peek_l3_ul_initial_ue(struct hnbgw_context_map *map, const RANAP_InitialUE_MessageIEs_t *ies)
+{
+	struct osmo_plmn_id local_plmn;
+
+	if (g_hnbgw->config.plmn.mcc) {
+		/* The user has configured a PLMN */
+		local_plmn = g_hnbgw->config.plmn;
+	} else {
+		/* The user has not configured a PLMN, guess from the InitialUE message's LAI IE's PLMN */
+		if (ies->lai.pLMNidentity.size < 3) {
+			LOGP(DCN, LOGL_ERROR, "Missing PLMN in RANAP InitialUE message\n");
+			return -EINVAL;
+		}
+		osmo_plmn_from_bcd(ies->lai.pLMNidentity.buf, &local_plmn);
+	}
+
+	return peek_l3_ul_nas(map, ies->nas_pdu.buf, ies->nas_pdu.size, &local_plmn);
+}
+
+/* Extract a Layer 3 message (NAS PDU) from the uplink RANAP message, and put the info obtained in map->l3.
+ * This is relevant for CN pooling, to decide which CN link to map the RUA context to. */
+int hnbgw_peek_l3_ul(struct hnbgw_context_map *map, struct msgb *ranap_msg)
+{
+	ranap_message *message = hnbgw_decode_ranap_cn_co(ranap_msg);
+	if (!message) {
+		LOGP(DCN, LOGL_ERROR, "Failed to decode RANAP PDU\n");
+		return -EINVAL;
+	}
+
+	switch (message->procedureCode) {
+	case RANAP_ProcedureCode_id_InitialUE_Message:
+		return peek_l3_ul_initial_ue(map, &message->msg.initialUE_MessageIEs);
+	default:
+		LOGP(DCN, LOGL_ERROR, "unexpected RANAP PDU in RUA Connect message: %s\n",
+		     get_value_string(ranap_procedure_code_vals, message->procedureCode));
+		return -ENOTSUP;
+	}
+}

src/osmo-hnbgw/hnbgw_pfcp.c

@@ -0,0 +1,184 @@
+/* PFCP link to UPF for osmo-hnbgw */
+/* (C) 2022 by sysmocom s.f.m.c. GmbH <info@sysmocom.de>
+ * All Rights Reserved
+ *
+ * Author: Neels Janosch Hofmeyr <nhofmeyr@sysmocom.de>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include <osmocom/core/sockaddr_str.h>
+#include <osmocom/core/stats.h>
+#include <osmocom/core/stat_item.h>
+#include <osmocom/pfcp/pfcp_endpoint.h>
+#include <osmocom/pfcp/pfcp_cp_peer.h>
+
+#include <osmocom/hnbgw/hnbgw.h>
+#include <osmocom/hnbgw/context_map.h>
+#include <osmocom/hnbgw/ps_rab_fsm.h>
+#include <osmocom/hnbgw/hnbgw_pfcp.h>
+
+static const struct osmo_stat_item_desc hnbgw_upf_stat_item_description[] = {
+	[HNBGW_UPF_STAT_ASSOCIATED] = { "pfcp_associated", "Associated to UPF through PFCP", OSMO_STAT_ITEM_NO_UNIT, 16, 0},
+};
+
+static const struct osmo_stat_item_group_desc hnbgw_upf_statg_desc = {
+	"upf",
+	"UPF Peer Statistics",
+	OSMO_STATS_CLASS_PEER,
+	ARRAY_SIZE(hnbgw_upf_stat_item_description),
+	hnbgw_upf_stat_item_description,
+};
+
+static void pfcp_set_msg_ctx(struct osmo_pfcp_endpoint *ep, struct osmo_pfcp_msg *m, struct osmo_pfcp_msg *req)
+{
+	if (!m->ctx.peer_fi)
+		osmo_pfcp_cp_peer_set_msg_ctx(g_hnbgw->pfcp.cp_peer, m);
+
+	/* If this is a response to an earlier request, just take the msg context from the request message.
+	 * In osmo-hnbgw, a session_fi always points at a ps_rab FSM. */
+	if (!m->ctx.session_fi && req && req->ctx.session_fi)
+		ps_rab_pfcp_set_msg_ctx(req->ctx.session_fi->priv, m);
+
+	/* Otherwise iterate all PS RABs in all hnb contexts matching on the SEID. This rarely happens at all: for tx,
+	 * ps_rab_new_pfcp_msg_tx() already sets the msg ctx, and for rx, we only expect to receive PFCP Responses,
+	 * which are handled above. The only time this will happen is when the UPF shuts down and sends a Deletion. */
+	if (!m->ctx.session_fi && m->h.seid_present && m->h.seid != 0) {
+		struct ps_rab *rab = ps_rab_find_by_seid(m->h.seid, m->rx);
+		if (rab)
+			ps_rab_pfcp_set_msg_ctx(rab, m);
+	}
+}
+
+static void pfcp_rx_msg(struct osmo_pfcp_endpoint *ep, struct osmo_pfcp_msg *m, struct osmo_pfcp_msg *req)
+{
+	switch (m->h.message_type) {
+
+		/* We only expect responses to requests. Those are handled by osmo_pfcp_msg.ctx.resp_cb. */
+
+		/* TODO: handle graceful shutdown from UPF (Session Modification? Deletion?) */
+
+	default:
+		LOGP(DLPFCP, LOGL_ERROR, "rx unexpected PFCP message: %s\n",
+		     osmo_pfcp_message_type_str(m->h.message_type));
+		return;
+	}
+}
+
+static void pfcp_cp_peer_assoc_cb(struct osmo_pfcp_cp_peer *cp_peer, bool associated)
+{
+	LOGP(DLPFCP, LOGL_NOTICE, "PFCP Peer associated: %s\n", associated ? "true" : "false");
+	HNBGW_UPF_STAT_SET(HNBGW_UPF_STAT_ASSOCIATED, associated ? 1 : 0);
+}
+
+int hnbgw_pfcp_init(void)
+{
+	struct osmo_pfcp_endpoint_cfg cfg;
+	struct osmo_pfcp_endpoint *ep;
+	struct osmo_sockaddr_str local_addr_str;
+	struct osmo_sockaddr_str upf_addr_str;
+	struct osmo_sockaddr upf_addr;
+
+	if (!hnb_gw_is_gtp_mapping_enabled()) {
+		LOGP(DLPFCP, LOGL_NOTICE, "No UPF configured, NOT setting up PFCP, NOT mapping GTP via UPF\n");
+		return 0;
+	}
+	LOGP(DLPFCP, LOGL_DEBUG, "%p cfg: pfcp remote-addr %s\n", g_hnbgw, g_hnbgw->config.pfcp.remote_addr);
+
+	if (!g_hnbgw->config.pfcp.local_addr) {
+		LOGP(DLPFCP, LOGL_ERROR, "Configuration error: missing local PFCP address, required for Node Id\n");
+		return -1;
+	}
+
+	g_hnbgw->pfcp.statg = osmo_stat_item_group_alloc(g_hnbgw, &hnbgw_upf_statg_desc, 0);
+	if (!g_hnbgw->pfcp.statg) {
+		LOGP(DLPFCP, LOGL_ERROR, "Failed creating UPF stats item group\n");
+		return -1;
+	}
+
+	cfg = (struct osmo_pfcp_endpoint_cfg){
+		.set_msg_ctx_cb = pfcp_set_msg_ctx,
+		.rx_msg_cb = pfcp_rx_msg,
+	};
+
+	/* Set up PFCP endpoint's local node id from local IP address. Parse address string into local_addr_str... */
+	if (osmo_sockaddr_str_from_str(&local_addr_str, g_hnbgw->config.pfcp.local_addr, g_hnbgw->config.pfcp.local_port)) {
+		LOGP(DLPFCP, LOGL_ERROR, "Error in PFCP local IP: %s\n",
+		     osmo_quote_str_c(OTC_SELECT, g_hnbgw->config.pfcp.local_addr, -1));
+		return -1;
+	}
+	/* ...and convert to osmo_sockaddr, write to ep->cfg */
+	if (osmo_sockaddr_str_to_sockaddr(&local_addr_str, &cfg.local_addr.u.sas)) {
+		LOGP(DLPFCP, LOGL_ERROR, "Error in PFCP local IP: %s\n",
+		     osmo_quote_str_c(OTC_SELECT, g_hnbgw->config.pfcp.local_addr, -1));
+		return -1;
+	}
+	/* also store the local addr as local Node ID */
+	if (osmo_pfcp_ie_node_id_from_osmo_sockaddr(&cfg.local_node_id, &cfg.local_addr)) {
+		LOGP(DLPFCP, LOGL_ERROR, "Error in PFCP local IP: %s\n",
+		     osmo_quote_str_c(OTC_SELECT, g_hnbgw->config.pfcp.local_addr, -1));
+		return -1;
+	}
+
+	g_hnbgw->pfcp.ep = ep = osmo_pfcp_endpoint_create(g_hnbgw, &cfg);
+	if (!ep) {
+		LOGP(DLPFCP, LOGL_ERROR, "Failed to allocate PFCP endpoint\n");
+		return -1;
+	}
+
+	/* Set up remote PFCP address to reach UPF at. First parse the string into upf_addr_str. */
+	if (osmo_sockaddr_str_from_str(&upf_addr_str, g_hnbgw->config.pfcp.remote_addr, g_hnbgw->config.pfcp.remote_port)) {
+		LOGP(DLPFCP, LOGL_ERROR, "Error in PFCP remote IP: %s\n",
+		     osmo_quote_str_c(OTC_SELECT, g_hnbgw->config.pfcp.remote_addr, -1));
+		return -1;
+	}
+	/* then convert upf_addr_str to osmo_sockaddr */
+	if (osmo_sockaddr_str_to_sockaddr(&upf_addr_str, &upf_addr.u.sas)) {
+		LOGP(DLPFCP, LOGL_ERROR, "Error in PFCP remote IP: %s\n",
+		     osmo_quote_str_c(OTC_SELECT, g_hnbgw->config.pfcp.remote_addr, -1));
+		return -1;
+	}
+
+	/* Start the socket */
+	if (osmo_pfcp_endpoint_bind(ep)) {
+		LOGP(DLPFCP, LOGL_ERROR, "Cannot bind PFCP endpoint\n");
+		return -1;
+	}
+
+	/* Associate with UPF */
+	g_hnbgw->pfcp.cp_peer = osmo_pfcp_cp_peer_alloc(g_hnbgw, ep, &upf_addr);
+	if (!g_hnbgw->pfcp.cp_peer) {
+		LOGP(DLPFCP, LOGL_ERROR, "Cannot allocate PFCP CP Peer FSM\n");
+		return -1;
+	}
+	if (osmo_pfcp_cp_peer_set_associated_cb(g_hnbgw->pfcp.cp_peer, pfcp_cp_peer_assoc_cb)) {
+		LOGP(DLPFCP, LOGL_ERROR, "Cannot Set PFCP CP Peer associated callback\n");
+		return -1;
+	}
+
+	if (osmo_pfcp_cp_peer_associate(g_hnbgw->pfcp.cp_peer)) {
+		LOGP(DLPFCP, LOGL_ERROR, "Cannot start PFCP CP Peer FSM\n");
+		return -1;
+	}
+
+	return 0;
+}
+
+void hnbgw_pfcp_release(void)
+{
+	if (!hnb_gw_is_gtp_mapping_enabled())
+		return;
+	osmo_stat_item_group_free(g_hnbgw->pfcp.statg);
+}

src/osmo-hnbgw/hnbgw_ranap.c

@@ -1,4 +1,4 @@
-/* hnb-gw specific code for RANAP */
+/* hnb-gw specific code for RANAP, 3GPP TS 25.413 */
 
 /* (C) 2015 by Harald Welte <laforge@gnumonks.org>
  * All Rights Reserved
@@ -18,10 +18,7 @@
  *
  */
 
-
-
-#include <osmocom/core/msgb.h>
-#include <osmocom/core/utils.h>
+#include "config.h"
 
 #include <unistd.h>
 #include <errno.h>
@@ -29,14 +26,34 @@
 
 #include "asn1helpers.h"
 
-#include <osmocom/hnbgw/hnbgw.h>
-#include <osmocom/hnbgw/hnbgw_rua.h>
+#include <osmocom/core/msgb.h>
+#include <osmocom/core/utils.h>
+
 #include <osmocom/ranap/ranap_common.h>
+#include <osmocom/ranap/ranap_common_ran.h>
+#include <osmocom/ranap/ranap_common_cn.h>
 #include <osmocom/ranap/ranap_ies_defs.h>
 #include <osmocom/ranap/ranap_msg_factory.h>
 
-static int ranap_tx_reset_ack(struct hnb_context *hnb,
-				RANAP_CN_DomainIndicator_t domain)
+#if ENABLE_PFCP
+#include <osmocom/pfcp/pfcp_cp_peer.h>
+#endif
+
+#include <osmocom/hnbgw/hnb.h>
+#include <osmocom/hnbgw/hnb_persistent.h>
+#include <osmocom/hnbgw/hnbgw.h>
+#include <osmocom/hnbgw/hnbgw_rua.h>
+#include <osmocom/hnbgw/hnbgw_cn.h>
+#include <osmocom/hnbgw/context_map.h>
+#include <osmocom/hnbgw/mgw_fsm.h>
+#include <osmocom/hnbgw/ps_rab_ass_fsm.h>
+#include <osmocom/hnbgw/kpi.h>
+
+/*****************************************************************************
+ * Processing of RANAP from the endpoint towards RAN (hNodeB), acting as CN
+ *****************************************************************************/
+
+static int ranap_tx_udt_dl_reset_ack(struct hnb_context *hnb, RANAP_CN_DomainIndicator_t domain)
 {
 	struct msgb *msg;
 	int rc;
@@ -52,7 +69,7 @@ static int ranap_tx_reset_ack(struct hnb_context *hnb,
 	return rc;
 }
 
-static int ranap_rx_init_reset(struct hnb_context *hnb, ANY_t *in)
+static int ranap_rx_udt_ul_init_reset(struct hnb_context *hnb, ANY_t *in)
 {
 	RANAP_ResetIEs_t ies;
 	int rc, is_ps = 0;
@@ -66,32 +83,38 @@ static int ranap_rx_init_reset(struct hnb_context *hnb, ANY_t *in)
 
 	LOGHNB(hnb, DRANAP, LOGL_INFO, "Rx RESET.req(%s,%s)\n", is_ps ? "ps" : "cs",
 		ranap_cause_str(&ies.cause));
+	HNBP_CTR_INC(hnb->persistent, is_ps ? HNB_CTR_RANAP_PS_RESET_REQ_UL : HNB_CTR_RANAP_CS_RESET_REQ_UL);
 
 	/* FIXME: Actually we have to wait for some guard time? */
 	/* FIXME: Reset all resources related to this HNB/RNC */
-	ranap_tx_reset_ack(hnb, ies.cN_DomainIndicator);
+	ranap_tx_udt_dl_reset_ack(hnb, ies.cN_DomainIndicator);
 
 	return 0;
 }
 
-static int ranap_rx_error_ind(struct hnb_context *hnb, ANY_t *in)
+static int ranap_rx_udt_ul_error_ind(struct hnb_context *hnb, ANY_t *in)
 {
 	RANAP_ErrorIndicationIEs_t ies;
 	int rc;
+	bool is_ps = false;
 
 	rc = ranap_decode_errorindicationies(&ies, in);
 	if (rc < 0)
 		return rc;
 
+	if (ies.cN_DomainIndicator == RANAP_CN_DomainIndicator_ps_domain)
+		is_ps = true;
+
 	if (ies.presenceMask & ERRORINDICATIONIES_RANAP_CAUSE_PRESENT) {
 		LOGHNB(hnb, DRANAP, LOGL_ERROR, "Rx ERROR.ind(%s)\n", ranap_cause_str(&ies.cause));
 	} else
 		LOGHNB(hnb, DRANAP, LOGL_ERROR, "Rx ERROR.ind\n");
+	HNBP_CTR_INC(hnb->persistent, is_ps ? HNB_CTR_RANAP_PS_ERR_IND_UL : HNB_CTR_RANAP_CS_ERR_IND_UL);
 
 	return 0;
 }
 
-static int ranap_rx_initiating_msg(struct hnb_context *hnb, RANAP_InitiatingMessage_t *imsg)
+static int ranap_rx_udt_ul_initiating_msg(struct hnb_context *hnb, RANAP_InitiatingMessage_t *imsg)
 {
 	int rc = 0;
 
@@ -105,12 +128,12 @@ static int ranap_rx_initiating_msg(struct hnb_context *hnb, RANAP_InitiatingMess
 	switch (imsg->procedureCode) {
 	case RANAP_ProcedureCode_id_Reset:
 		/* Reset request */
-		rc = ranap_rx_init_reset(hnb, &imsg->value);
+		rc = ranap_rx_udt_ul_init_reset(hnb, &imsg->value);
 		break;
 	case RANAP_ProcedureCode_id_OverloadControl: /* Overload ind */
 		break;
 	case RANAP_ProcedureCode_id_ErrorIndication: /* Error ind */
-		rc = ranap_rx_error_ind(hnb, &imsg->value);
+		rc = ranap_rx_udt_ul_error_ind(hnb, &imsg->value);
 		break;
 	case RANAP_ProcedureCode_id_ResetResource: /* request */
 	case RANAP_ProcedureCode_id_InformationTransfer:
@@ -128,7 +151,7 @@ static int ranap_rx_initiating_msg(struct hnb_context *hnb, RANAP_InitiatingMess
 	return rc;
 }
 
-static int ranap_rx_successful_msg(struct hnb_context *hnb, RANAP_SuccessfulOutcome_t *imsg)
+static int ranap_rx_udt_ul_successful_msg(struct hnb_context *hnb, RANAP_SuccessfulOutcome_t *imsg)
 {
 	/* according tot the spec, we can primarily receive Overload,
 	 * Reset, Reset ACK, Error Indication, reset Resource, Reset
@@ -158,16 +181,16 @@ static int ranap_rx_successful_msg(struct hnb_context *hnb, RANAP_SuccessfulOutc
 
 
 
-static int _hnbgw_ranap_rx(struct hnb_context *hnb, RANAP_RANAP_PDU_t *pdu)
+static int _hnbgw_ranap_rx_udt_ul(struct hnb_context *hnb, RANAP_RANAP_PDU_t *pdu)
 {
 	int rc = 0;
 
 	switch (pdu->present) {
 	case RANAP_RANAP_PDU_PR_initiatingMessage:
-		rc = ranap_rx_initiating_msg(hnb, &pdu->choice.initiatingMessage);
+		rc = ranap_rx_udt_ul_initiating_msg(hnb, &pdu->choice.initiatingMessage);
 		break;
 	case RANAP_RANAP_PDU_PR_successfulOutcome:
-		rc = ranap_rx_successful_msg(hnb, &pdu->choice.successfulOutcome);
+		rc = ranap_rx_udt_ul_successful_msg(hnb, &pdu->choice.successfulOutcome);
 		break;
 	case RANAP_RANAP_PDU_PR_unsuccessfulOutcome:
 		LOGHNB(hnb, DRANAP, LOGL_NOTICE, "Received unsupported RANAP "
@@ -183,8 +206,8 @@ static int _hnbgw_ranap_rx(struct hnb_context *hnb, RANAP_RANAP_PDU_t *pdu)
 	return rc;
 }
 
-
-int hnbgw_ranap_rx(struct msgb *msg, uint8_t *data, size_t len)
+/* receive a RNAAP Unit-Data message in uplink direction */
+int hnbgw_ranap_rx_udt_ul(struct msgb *msg, uint8_t *data, size_t len)
 {
 	RANAP_RANAP_PDU_t _pdu, *pdu = &_pdu;
 	struct hnb_context *hnb = msg->dst;
@@ -199,11 +222,460 @@ int hnbgw_ranap_rx(struct msgb *msg, uint8_t *data, size_t len)
 		return -1;
 	}
 
-	rc = _hnbgw_ranap_rx(hnb, pdu);
+	rc = _hnbgw_ranap_rx_udt_ul(hnb, pdu);
 
 	return rc;
 }
 
+static int destruct_ranap_cn_rx_co_ies(ranap_message *ranap_message_p)
+{
+	ranap_cn_rx_co_free(ranap_message_p);
+	return 0;
+}
+
+/* Decode UL RANAP message with convenient memory freeing: just talloc_free() the returned pointer..
+ * Allocate a ranap_message from OTC_SELECT, decode RANAP msgb into it, attach a talloc destructor that calls
+ * ranap_cn_rx_co_free() upon talloc_free(), and return the decoded ranap_message. */
+ranap_message *hnbgw_decode_ranap_cn_co(struct msgb *ranap_msg)
+{
+	int rc;
+	ranap_message *message;
+
+	if (!msg_has_l2_data(ranap_msg))
+		return NULL;
+	message = talloc_zero(OTC_SELECT, ranap_message);
+	rc = ranap_cn_rx_co_decode2(message, msgb_l2(ranap_msg), msgb_l2len(ranap_msg));
+	if (rc != 0) {
+		talloc_free(message);
+		return NULL;
+	}
+	talloc_set_destructor(message, destruct_ranap_cn_rx_co_ies);
+	return message;
+}
+
+/* Process a received RANAP PDU through SCCP DATA.ind coming from CN (MSC/SGSN)
+ * ranap_msg is owned by OTC_SELECT. */
+int hnbgw_ranap_rx_data_ul(struct hnbgw_context_map *map, struct msgb *ranap_msg)
+{
+	OSMO_ASSERT(map);
+	OSMO_ASSERT(msg_has_l2_data(ranap_msg));
+
+	ranap_message *message = hnbgw_decode_ranap_cn_co(ranap_msg);
+	if (message) {
+		LOG_MAP(map, DHNB, LOGL_DEBUG, "rx from RUA: RANAP %s\n",
+			get_value_string(ranap_procedure_code_vals, message->procedureCode));
+
+		kpi_ranap_process_ul(map, message);
+
+		if (!map->is_ps) {
+			/* See if it is a RAB Assignment Response message from RUA to SCCP, where we need to change the user plane
+			 * information, for RTP mapping via MGW, or GTP mapping via UPF. */
+			switch (message->procedureCode) {
+			case RANAP_ProcedureCode_id_RAB_Assignment:
+				/* mgw_fsm_handle_rab_ass_resp() may take ownership of "ranap_msg" (prim->oph) and "message" */
+				return mgw_fsm_handle_cs_rab_ass_resp(map, ranap_msg, message);
+			}
+		} else {
+#if ENABLE_PFCP
+			if (hnb_gw_is_gtp_mapping_enabled()) {
+				/* map->is_ps == true and PFCP is enabled in osmo-hnbgw.cfg */
+				switch (message->procedureCode) {
+				case RANAP_ProcedureCode_id_RAB_Assignment:
+					/* ps_rab_ass_fsm() may take ownership of "ranap_msg" (prim->oph) and "message" */
+					return hnbgw_gtpmap_rx_rab_ass_resp(map, ranap_msg, message);
+				}
+			}
+#endif
+		}
+	}
+
+	/* It was not a RAB Assignment Response that needed to be intercepted. Forward as-is to SCCP. */
+	return map_sccp_dispatch(map, MAP_SCCP_EV_TX_DATA_REQUEST, ranap_msg);
+}
+
+/*****************************************************************************
+ * Processing of RANAP from the endpoint towards CN (MSC/SGSN), acting as RAN
+ *****************************************************************************/
+
+static int cn_ranap_rx_reset_cmd(struct hnbgw_cnlink *cnlink,
+				 const struct osmo_scu_unitdata_param *unitdata,
+				 RANAP_InitiatingMessage_t *imsg)
+{
+	RANAP_CN_DomainIndicator_t domain;
+	RANAP_ResetIEs_t ies;
+	int rc;
+
+	rc = ranap_decode_reseties(&ies, &imsg->value);
+	domain = ies.cN_DomainIndicator;
+	ranap_free_reseties(&ies);
+
+	if (rc) {
+		LOG_CNLINK(cnlink, DCN, LOGL_ERROR, "Rx RESET: cannot decode IEs\n");
+		return -1;
+	}
+
+	if (cnlink->pool->domain != domain) {
+		LOG_CNLINK(cnlink, DCN, LOGL_ERROR, "Rx RESET indicates domain %s, but this is %s on domain %s\n",
+			   ranap_domain_name(domain), cnlink->name, ranap_domain_name(cnlink->pool->domain));
+		return -1;
+	}
+
+	cnlink_rx_reset_cmd(cnlink);
+	return 0;
+}
+
+static const struct value_string ranap_paging_area_id_names[] = {
+	{ RANAP_PagingAreaID_PR_NOTHING, "NOTHING" },
+	{ RANAP_PagingAreaID_PR_lAI, "LAI" },
+	{ RANAP_PagingAreaID_PR_rAI, "RAI" },
+	{ 0, NULL }
+};
+
+static bool hnb_paging_area_id_match(const struct hnb_context *hnb,
+				     enum RANAP_PagingAreaID_PR t,
+				     const struct osmo_routing_area_id *rai)
+{
+	switch (t) {
+	case RANAP_PagingAreaID_PR_NOTHING:
+		return true;
+	case RANAP_PagingAreaID_PR_rAI:
+		if (hnb->id.rac != rai->rac)
+			return false;
+		/* fall through */
+	case RANAP_PagingAreaID_PR_lAI:
+		if (hnb->id.lac != rai->lac.lac)
+			return false;
+		if (osmo_plmn_cmp(&hnb->id.plmn, &rai->lac.plmn))
+			return false;
+		/* fall through */
+	}
+	return true;
+}
+
+static int lai_from_RANAP_RANAP_LAI(struct osmo_location_area_id *lai, const RANAP_LAI_t *ranap_lai)
+{
+	if (ranap_lai->pLMNidentity.size < 3)
+		return -EINVAL;
+	osmo_plmn_from_bcd(ranap_lai->pLMNidentity.buf, &lai->plmn);
+	lai->lac = asn1str_to_u16(&ranap_lai->lAC);
+	return 0;
+}
+
+static int rai_from_RANAP_PagingAreaID(struct osmo_routing_area_id *rai, const RANAP_PagingAreaID_t *paid)
+{
+	switch (paid->present) {
+	case RANAP_PagingAreaID_PR_NOTHING:
+		break;
+	case RANAP_PagingAreaID_PR_lAI:
+		return lai_from_RANAP_RANAP_LAI(&rai->lac, &paid->choice.lAI);
+	case RANAP_PagingAreaID_PR_rAI:
+		rai->rac = asn1str_to_u8(&paid->choice.rAI.rAC);
+		return lai_from_RANAP_RANAP_LAI(&rai->lac, &paid->choice.rAI.lAI);
+	}
+	return 0;
+}
+
+/* 3GPP TS 25.413 8.15 */
+static int cn_ranap_rx_paging_cmd(struct hnbgw_cnlink *cnlink,
+				  RANAP_InitiatingMessage_t *imsg,
+				  const uint8_t *data, unsigned int len)
+{
+	RANAP_PagingIEs_t ies;
+	RANAP_CN_DomainIndicator_t domain;
+	const char *errmsg;
+	struct hnb_context *hnb;
+	bool is_ps = cnlink->pool->domain == DOMAIN_PS;
+	bool forwarded = false;
+	bool page_area_present;
+	struct osmo_routing_area_id page_rai = {};
+
+	if (ranap_decode_pagingies(&ies, &imsg->value) < 0) {
+		LOG_CNLINK(cnlink, DCN, LOGL_ERROR,
+			   "Rx Paging from CN: decoding RANAP IEs failed\n");
+		return -1;
+	}
+	domain = ies.cN_DomainIndicator;
+	page_area_present = (ies.presenceMask & PAGINGIES_RANAP_PAGINGAREAID_PRESENT);
+
+	if (cnlink->pool->domain != domain) {
+		LOG_CNLINK(cnlink, DCN, LOGL_ERROR,
+			   "Rx Paging from CN: message indicates domain %s, but cnlink is on domain %s\n",
+			   ranap_domain_name(domain),
+			   ranap_domain_name(cnlink->pool->domain));
+		goto free_ies_ret;
+	}
+
+	if (page_area_present) {
+		if (rai_from_RANAP_PagingAreaID(&page_rai, &ies.pagingAreaID) < 0) {
+			LOG_CNLINK(cnlink, DCN, LOGL_ERROR,
+				   "Rx Paging from CN: decoding RANAP IE Paging Area ID failed, broadcasting to all HNBs\n");
+			/* fail over to broadcast... */
+			page_area_present = false;
+		}
+	}
+
+	LOG_CNLINK(cnlink, DCN, LOGL_DEBUG,
+		   "Rx Paging from CN: %s PagingAreaID: %s %s\n",
+		   ranap_domain_name(domain),
+		   page_area_present ?
+			get_value_string(ranap_paging_area_id_names, ies.pagingAreaID.present) :
+			"NOT_PRESENT",
+		   osmo_rai_name2(&page_rai)
+		);
+
+	llist_for_each_entry(hnb, &g_hnbgw->hnb_list, list) {
+		if (!hnb->hnb_registered)
+			continue;
+		if (page_area_present &&
+		    !hnb_paging_area_id_match(hnb, ies.pagingAreaID.present, &page_rai))
+			continue;
+
+		if (is_ps)
+			HNBP_CTR_INC(hnb->persistent, HNB_CTR_PS_PAGING_ATTEMPTED);
+		else
+			HNBP_CTR_INC(hnb->persistent, HNB_CTR_CS_PAGING_ATTEMPTED);
+		if (rua_tx_udt(hnb, data, len) == 0)
+			forwarded = true;
+	}
+
+	if (forwarded) {
+		/* If Paging command was forwarded anywhere, store a record for it, to match paging response: */
+		errmsg = cnlink_paging_add_ranap(cnlink, &ies);
+		if (errmsg) {
+			LOG_CNLINK(cnlink, DCN, LOGL_ERROR,
+				   "Rx Paging from CN: %s. Skip storing paging record."
+				   " Later on, the Paging Response may be forwarded to the wrong CN peer.\n",
+				   errmsg);
+			goto free_ies_ret;
+		}
+	}
+	ranap_free_pagingies(&ies);
+	return 0;
+
+free_ies_ret:
+	ranap_free_pagingies(&ies);
+	return -1;
+}
+
+static int ranap_rx_udt_dl_initiating_msg(struct hnbgw_cnlink *cnlink,
+					  const struct osmo_scu_unitdata_param *unitdata,
+					  RANAP_InitiatingMessage_t *imsg,
+					  const uint8_t *data, unsigned int len)
+{
+	switch (imsg->procedureCode) {
+	case RANAP_ProcedureCode_id_Reset:
+		CNLINK_CTR_INC(cnlink, CNLINK_CTR_RANAP_RX_UDT_RESET);
+		return cn_ranap_rx_reset_cmd(cnlink, unitdata, imsg);
+	case RANAP_ProcedureCode_id_Paging:
+		CNLINK_CTR_INC(cnlink, CNLINK_CTR_RANAP_RX_UDT_PAGING);
+		return cn_ranap_rx_paging_cmd(cnlink, imsg, data, len);
+	case RANAP_ProcedureCode_id_OverloadControl: /* Overload ind */
+		CNLINK_CTR_INC(cnlink, CNLINK_CTR_RANAP_RX_UDT_OVERLOAD_IND);
+		break;
+	case RANAP_ProcedureCode_id_ErrorIndication: /* Error ind */
+		CNLINK_CTR_INC(cnlink, CNLINK_CTR_RANAP_RX_UDT_ERROR_IND);
+		break;
+	case RANAP_ProcedureCode_id_ResetResource: /* request */
+	case RANAP_ProcedureCode_id_InformationTransfer:
+	case RANAP_ProcedureCode_id_DirectInformationTransfer:
+	case RANAP_ProcedureCode_id_UplinkInformationExchange:
+		CNLINK_CTR_INC(cnlink, CNLINK_CTR_RANAP_RX_UDT_UNSUPPORTED);
+		LOGP(DRANAP, LOGL_NOTICE, "Received unsupported RANAP "
+		     "Procedure %ld from CN, ignoring\n", imsg->procedureCode);
+		break;
+	default:
+		CNLINK_CTR_INC(cnlink, CNLINK_CTR_RANAP_RX_UDT_UNKNOWN);
+		LOGP(DRANAP, LOGL_NOTICE, "Received suspicious RANAP "
+		     "Procedure %ld from CN, ignoring\n", imsg->procedureCode);
+		break;
+	}
+	return 0;
+}
+
+static int cn_ranap_rx_reset_ack(struct hnbgw_cnlink *cnlink,
+				 RANAP_SuccessfulOutcome_t *omsg)
+{
+	RANAP_CN_DomainIndicator_t domain;
+	RANAP_ResetAcknowledgeIEs_t ies;
+	int rc;
+
+	rc = ranap_decode_resetacknowledgeies(&ies, &omsg->value);
+	domain = ies.cN_DomainIndicator;
+	ranap_free_resetacknowledgeies(&ies);
+
+	if (rc) {
+		LOG_CNLINK(cnlink, DCN, LOGL_ERROR, "Rx RESET ACK: cannot decode IEs\n");
+		return -1;
+	}
+
+	if (cnlink->pool->domain != domain) {
+		LOG_CNLINK(cnlink, DCN, LOGL_ERROR, "Rx RESET ACK indicates domain %s, but this is %s on domain %s\n",
+			   ranap_domain_name(domain), cnlink->name, ranap_domain_name(cnlink->pool->domain));
+		return -1;
+	}
+
+	cnlink_rx_reset_ack(cnlink);
+	return 0;
+}
+
+static int ranap_rx_udt_dl_successful_msg(struct hnbgw_cnlink *cnlink,
+					  RANAP_SuccessfulOutcome_t *omsg)
+{
+	switch (omsg->procedureCode) {
+	case RANAP_ProcedureCode_id_Reset: /* Reset acknowledge */
+		CNLINK_CTR_INC(cnlink, CNLINK_CTR_RANAP_RX_UDT_RESET);
+		return cn_ranap_rx_reset_ack(cnlink, omsg);
+	case RANAP_ProcedureCode_id_ResetResource: /* response */
+	case RANAP_ProcedureCode_id_InformationTransfer:
+	case RANAP_ProcedureCode_id_DirectInformationTransfer:
+	case RANAP_ProcedureCode_id_UplinkInformationExchange:
+		CNLINK_CTR_INC(cnlink, CNLINK_CTR_RANAP_RX_UDT_UNSUPPORTED);
+		LOGP(DRANAP, LOGL_NOTICE, "Received unsupported RANAP "
+		     "Procedure %ld from CN, ignoring\n", omsg->procedureCode);
+		break;
+	default:
+		CNLINK_CTR_INC(cnlink, CNLINK_CTR_RANAP_RX_UDT_UNKNOWN);
+		LOGP(DRANAP, LOGL_NOTICE, "Received suspicious RANAP "
+		     "Procedure %ld from CN, ignoring\n", omsg->procedureCode);
+		break;
+	}
+	return 0;
+}
+
+static int _hnbgw_ranap_rx_udt_dl(struct hnbgw_cnlink *cnlink,
+				 const struct osmo_scu_unitdata_param *unitdata,
+				 RANAP_RANAP_PDU_t *pdu, const uint8_t *data, unsigned int len)
+{
+	int rc;
+
+	switch (pdu->present) {
+	case RANAP_RANAP_PDU_PR_initiatingMessage:
+		rc = ranap_rx_udt_dl_initiating_msg(cnlink, unitdata, &pdu->choice.initiatingMessage, data, len);
+		break;
+	case RANAP_RANAP_PDU_PR_successfulOutcome:
+		rc = ranap_rx_udt_dl_successful_msg(cnlink, &pdu->choice.successfulOutcome);
+		break;
+	case RANAP_RANAP_PDU_PR_unsuccessfulOutcome:
+		LOGP(DRANAP, LOGL_NOTICE, "Received unsupported RANAP "
+		     "unsuccessful outcome procedure %ld from CN, ignoring\n",
+		     pdu->choice.unsuccessfulOutcome.procedureCode);
+		rc = -ENOTSUP;
+		break;
+	default:
+		LOGP(DRANAP, LOGL_NOTICE, "Received suspicious RANAP "
+		     "presence %u from CN, ignoring\n", pdu->present);
+		rc = -EINVAL;
+		break;
+	}
+
+	return rc;
+}
+
+int hnbgw_ranap_rx_udt_dl(struct hnbgw_cnlink *cnlink, const struct osmo_scu_unitdata_param *unitdata,
+			  const uint8_t *data, unsigned int len)
+{
+	RANAP_RANAP_PDU_t _pdu, *pdu = &_pdu;
+	asn_dec_rval_t dec_ret;
+	int rc;
+
+	memset(pdu, 0, sizeof(*pdu));
+	dec_ret = aper_decode(NULL, &asn_DEF_RANAP_RANAP_PDU, (void **) &pdu,
+			      data, len, 0, 0);
+	if (dec_ret.code != RC_OK) {
+		LOGP(DRANAP, LOGL_ERROR, "Error in RANAP ASN.1 decode\n");
+		return -1;
+	}
+
+	rc = _hnbgw_ranap_rx_udt_dl(cnlink, unitdata, pdu, data, len);
+	ASN_STRUCT_FREE_CONTENTS_ONLY(asn_DEF_RANAP_RANAP_PDU, pdu);
+
+	return rc;
+}
+
+static int destruct_ranap_ran_rx_co_ies(ranap_message *ranap_message_p)
+{
+	ranap_ran_rx_co_free(ranap_message_p);
+	return 0;
+}
+
+/* Decode DL RANAP message with convenient memory freeing: just talloc_free() the returned pointer..
+ * Allocate a ranap_message from OTC_SELECT, decode RANAP msgb into it, attach a talloc destructor that calls
+ * ranap_cn_rx_co_free() upon talloc_free(), and return the decoded ranap_message. */
+static ranap_message *hnbgw_decode_ranap_ran_co(struct msgb *ranap_msg)
+{
+	int rc;
+	ranap_message *message;
+
+	if (!msg_has_l2_data(ranap_msg))
+		return NULL;
+	message = talloc_zero(OTC_SELECT, ranap_message);
+	rc = ranap_ran_rx_co_decode(NULL, message, msgb_l2(ranap_msg), msgb_l2len(ranap_msg));
+	if (rc != 0) {
+		talloc_free(message);
+		return NULL;
+	}
+	talloc_set_destructor(message, destruct_ranap_ran_rx_co_ies);
+	return message;
+}
+
+/* Process a received RANAP PDU through SCCP DATA.ind coming from CN (MSC/SGSN)
+ * ranap_msg is owned by OTC_SELECT. */
+int hnbgw_ranap_rx_data_dl(struct hnbgw_context_map *map, struct msgb *ranap_msg)
+{
+	OSMO_ASSERT(map);
+	OSMO_ASSERT(msg_has_l2_data(ranap_msg));
+
+	/* See if it is a RAB Assignment Request message from SCCP to RUA, where we need to change the user plane
+	 * information, for RTP mapping via MGW, or GTP mapping via UPF. */
+	ranap_message *message = hnbgw_decode_ranap_ran_co(ranap_msg);
+	if (message) {
+		LOG_MAP(map, DCN, LOGL_DEBUG, "rx from SCCP: RANAP %s\n",
+			get_value_string(ranap_procedure_code_vals, message->procedureCode));
+
+		kpi_ranap_process_dl(map, message);
+
+		if (!map->is_ps) {
+			/* Circuit-Switched. Set up mapping of RTP ports via MGW */
+			switch (message->procedureCode) {
+			case RANAP_ProcedureCode_id_RAB_Assignment:
+				/* mgw_fsm_alloc_and_handle_rab_ass_req() takes ownership of (ranap) message */
+				return handle_cs_rab_ass_req(map, ranap_msg, message);
+			case RANAP_ProcedureCode_id_Iu_Release:
+				/* Any IU Release will terminate the MGW FSM, the message itsself is not passed to the
+				 * FSM code. It is just forwarded normally by map_rua_tx_dt() below. */
+				mgw_fsm_release(map);
+				break;
+			}
+#if ENABLE_PFCP
+		} else {
+			switch (message->procedureCode) {
+			case RANAP_ProcedureCode_id_RAB_Assignment:
+				/* If a UPF is configured, handle the RAB Assignment via ps_rab_ass_fsm, and replace the
+				 * GTP F-TEIDs in the RAB Assignment message before passing it on to RUA. */
+				if (hnb_gw_is_gtp_mapping_enabled()) {
+					LOG_MAP(map, DCN, LOGL_DEBUG,
+						"RAB Assignment: setting up GTP tunnel mapping via UPF %s\n",
+						osmo_sockaddr_to_str_c(OTC_SELECT, osmo_pfcp_cp_peer_get_remote_addr(g_hnbgw->pfcp.cp_peer)));
+					return hnbgw_gtpmap_rx_rab_ass_req(map, ranap_msg, message);
+				}
+				/* If no UPF is configured, directly forward the message as-is (no GTP mapping). */
+				LOG_MAP(map, DCN, LOGL_DEBUG, "RAB Assignment: no UPF configured, forwarding as-is\n");
+				break;
+
+			case RANAP_ProcedureCode_id_Iu_Release:
+				/* Any IU Release will terminate the MGW FSM, the message itsself is not passed to the
+				 * FSM code. It is just forwarded normally by map_rua_tx_dt() below. */
+				hnbgw_gtpmap_release(map);
+				break;
+			}
+#endif
+		}
+	}
+
+	/* It was not a RAB Assignment Request that needed to be intercepted. Forward as-is to RUA. */
+	return map_rua_dispatch(map, MAP_RUA_EV_TX_DIRECT_TRANSFER, ranap_msg);
+}
+
 int hnbgw_ranap_init(void)
 {
 	return 0;

src/osmo-hnbgw/hnbgw_rua.c

@@ -1,4 +1,4 @@
-/* hnb-gw specific code for RUA (Ranap User Adaption) */
+/* hnb-gw specific code for RUA (Ranap User Adaption), 3GPP TS 25.468 */
 
 /* (C) 2015 by Harald Welte <laforge@gnumonks.org>
  * All Rights Reserved
@@ -18,6 +18,7 @@
  *
  */
 
+#include "config.h"
 
 #include <osmocom/core/msgb.h>
 #include <osmocom/core/utils.h>
@@ -32,30 +33,26 @@
 
 #include "asn1helpers.h"
 
-#include <osmocom/hnbgw/hnbgw.h>
+#include <osmocom/hnbgw/hnb.h>
+#include <osmocom/hnbgw/hnb_persistent.h>
+#include <osmocom/hnbgw/hnbgw_cn.h>
 #include <osmocom/hnbgw/hnbgw_ranap.h>
 #include <osmocom/rua/rua_common.h>
 #include <osmocom/rua/rua_ies_defs.h>
 #include <osmocom/hnbgw/context_map.h>
+#include <osmocom/hnbgw/hnbgw_rua.h>
 #include <osmocom/hnbap/HNBAP_CN-DomainIndicator.h>
 
-static const char *cn_domain_indicator_to_str(RUA_CN_DomainIndicator_t cN_DomainIndicator)
-{
-	switch (cN_DomainIndicator) {
-	case RUA_CN_DomainIndicator_cs_domain:
-		return "IuCS";
-	case RUA_CN_DomainIndicator_ps_domain:
-		return "IuPS";
-	default:
-		return "(unknown-domain)";
-	}
-}
-
 static int hnbgw_rua_tx(struct hnb_context *ctx, struct msgb *msg)
 {
 	if (!msg)
 		return -EINVAL;
 
+	if (!ctx || !ctx->conn) {
+		LOGHNB(ctx, DRUA, LOGL_ERROR, "RUA context to this HNB is not connected, cannot transmit message\n");
+		return -ENOTCONN;
+	}
+
 	msgb_sctp_ppid(msg) = IUH_PPI_RUA;
 	osmo_stream_srv_send(ctx->conn, msg);
 
@@ -87,6 +84,7 @@ int rua_tx_udt(struct hnb_context *hnb, const uint8_t *data, unsigned int len)
 	ASN_STRUCT_FREE_CONTENTS_ONLY(asn_DEF_RUA_ConnectionlessTransfer, &out);
 
 	LOGHNB(hnb, DRUA, LOGL_DEBUG, "transmitting RUA payload of %u bytes\n", msgb_length(msg));
+	HNBP_CTR_INC(hnb->persistent, HNB_CTR_RUA_UDT_DL);
 
 	return hnbgw_rua_tx(hnb, msg);
 }
@@ -122,8 +120,9 @@ int rua_tx_dt(struct hnb_context *hnb, int is_ps, uint32_t context_id,
 					      &out);
 	ASN_STRUCT_FREE_CONTENTS_ONLY(asn_DEF_RUA_DirectTransfer, &out);
 
-	LOGHNB(hnb, DRUA, LOGL_DEBUG, "transmitting RUA (cn=%s) payload of %u bytes\n",
+	LOGHNB(hnb, DRUA, LOGL_DEBUG, "transmitting RUA DirectTransfer (cn=%s) payload of %u bytes\n",
 		is_ps ? "ps" : "cs", msgb_length(msg));
+	HNBP_CTR_INC(hnb->persistent, is_ps ? HNB_CTR_RUA_PS_DT_DL : HNB_CTR_RUA_CS_DT_DL);
 
 	return hnbgw_rua_tx(hnb, msg);
 }
@@ -150,8 +149,6 @@ int rua_tx_disc(struct hnb_context *hnb, int is_ps, uint32_t context_id,
 		ies.ranaP_Message.size = len;
 	}
 
-	/* FIXME: msgb_free(msg)? ownership not yet clear */
-
 	memset(&out, 0, sizeof(out));
 	rc = rua_encode_disconnecties(&out, &ies);
 	if (rc < 0)
@@ -163,38 +160,95 @@ int rua_tx_disc(struct hnb_context *hnb, int is_ps, uint32_t context_id,
 					      &out);
 	ASN_STRUCT_FREE_CONTENTS_ONLY(asn_DEF_RUA_Disconnect, &out);
 
-	LOGHNB(hnb, DRUA, LOGL_DEBUG, "transmitting RUA (cn=%s) payload of %u bytes\n",
-		is_ps ? "ps" : "cs", msgb_length(msg));
-
+	LOGHNB(hnb, DRUA, LOGL_DEBUG, "transmitting RUA Disconnect (cn=%s) payload of %u bytes\n",
+	       is_ps ? "ps" : "cs", msgb_length(msg));
+	HNBP_CTR_INC(hnb->persistent, is_ps ? HNB_CTR_RUA_PS_DISCONNECT_DL : HNB_CTR_RUA_CS_DISCONNECT_DL);
 
 	return hnbgw_rua_tx(hnb, msg);
 }
 
+/* Send Disconnect to RUA without RANAP data */
+static void rua_tx_disc_conn_fail(struct hnb_context *hnb, bool is_ps, uint32_t context_id)
+{
+	RUA_Cause_t rua_cause = {
+		.present = RUA_Cause_PR_radioNetwork,
+		.choice.radioNetwork = RUA_CauseRadioNetwork_connect_failed,
+	};
 
+	LOG_HNBP(hnb->persistent, LOGL_INFO, "Tx RUA Disconnect\n");
 
-/* forward a RUA message to the SCCP User API to SCCP */
+	if (rua_tx_disc(hnb, is_ps, context_id, &rua_cause, NULL, 0))
+		LOG_HNBP(hnb->persistent, LOGL_ERROR, "Failed to send Disconnect to RUA\n");
+}
+
+static struct value_string rua_procedure_code_names[] = {
+	{ RUA_ProcedureCode_id_Connect, "Connect" },
+	{ RUA_ProcedureCode_id_DirectTransfer, "DirectTransfer" },
+	{ RUA_ProcedureCode_id_Disconnect, "Disconnect" },
+	{ RUA_ProcedureCode_id_ConnectionlessTransfer, "ConnectionlessTransfer" },
+	{ RUA_ProcedureCode_id_ErrorIndication, "ErrorIndication" },
+	{ RUA_ProcedureCode_id_privateMessage, "PrivateMessage" },
+	{}
+};
+
+static inline const char *rua_procedure_code_name(enum RUA_ProcedureCode val)
+{
+	return get_value_string(rua_procedure_code_names, val);
+}
+
+static struct hnbgw_context_map *create_context_map(struct hnb_context *hnb, uint32_t rua_ctx_id, bool is_ps,
+						    struct msgb *ranap_msg)
+{
+	struct hnbgw_context_map *map;
+	struct hnbgw_cnlink *cnlink;
+
+	/* Establish a new context map. From the RUA Connect, extract a mobile identity, if any, and select a CN link
+	 * based on an NRI found in the mobile identity, if any. */
+
+	/* Allocate a map for logging context */
+	map = context_map_alloc(hnb, rua_ctx_id, is_ps);
+	OSMO_ASSERT(map);
+
+	if (hnbgw_peek_l3_ul(map, ranap_msg))
+		LOGP(DCN, LOGL_NOTICE, "Failed to extract Mobile Identity from RUA Connect message's RANAP payload\n");
+	/* map->l3 now contains all the interesting information from the NAS PDU, if any.
+	 * If no useful information could be decoded, still continue to select a hopefully adequate link by round robin.
+	 */
+
+	cnlink = hnbgw_cnlink_select(map);
+	if (!cnlink) {
+		LOG_MAP(map, DCN, LOGL_ERROR, "Failed to select %s link\n", is_ps ? "IuPS" : "IuCS");
+		context_map_free(map);
+		return NULL;
+	}
+
+	if (context_map_set_cnlink(map, cnlink)) {
+		LOG_MAP(map, DCN, LOGL_ERROR, "Failed to establish link to %s\n", cnlink->name);
+		context_map_free(map);
+		return NULL;
+	}
+
+	return map;
+}
+
+/* dispatch a RUA connection-oriented message received from a HNB to a context mapping's RUA FSM, so that it is
+ * forwarded to the CN via SCCP connection-oriented messages.
+ * Connectionless messages are handled in hnbgw_ranap_rx_udt_ul() instead, not here. */
 static int rua_to_scu(struct hnb_context *hnb,
 		      RUA_CN_DomainIndicator_t cN_DomainIndicator,
-		      enum osmo_scu_prim_type type,
+		      enum RUA_ProcedureCode rua_procedure,
 		      uint32_t context_id, uint32_t cause,
 		      const uint8_t *data, unsigned int len)
 {
-	struct msgb *msg;
-	struct osmo_scu_prim *prim;
+	struct msgb *ranap_msg = NULL;
 	struct hnbgw_context_map *map = NULL;
-	struct hnbgw_cnlink *cn = hnb->gw->sccp.cnlink;
-	struct osmo_sccp_addr *remote_addr;
 	bool is_ps;
-	bool release_context_map = false;
-	int rc;
 
 	switch (cN_DomainIndicator) {
 	case RUA_CN_DomainIndicator_cs_domain:
-		remote_addr = &hnb->gw->sccp.iucs_remote_addr;
 		is_ps = false;
 		break;
 	case RUA_CN_DomainIndicator_ps_domain:
-		remote_addr = &hnb->gw->sccp.iups_remote_addr;
 		is_ps = true;
 		break;
 	default:
@@ -202,75 +256,78 @@ static int rua_to_scu(struct hnb_context *hnb,
 		return -1;
 	}
 
-	if (!cn) {
-		LOGHNB(hnb, DRUA, LOGL_NOTICE, "CN=NULL, discarding message\n");
-		return 0;
-	}
-
-	msg = msgb_alloc(1500, "rua_to_sccp");
-
-	prim = (struct osmo_scu_prim *) msgb_put(msg, sizeof(*prim));
-	osmo_prim_init(&prim->oph, SCCP_SAP_USER, type, PRIM_OP_REQUEST, msg);
-
-	switch (type) {
-	case OSMO_SCU_PRIM_N_UNITDATA:
-		LOGHNB(hnb, DRUA, LOGL_DEBUG, "rua_to_scu() %s to %s, rua_ctx_id %u (unitdata, no scu_conn_id)\n",
-			cn_domain_indicator_to_str(cN_DomainIndicator), osmo_sccp_addr_dump(remote_addr), context_id);
-		break;
-	default:
-		map = context_map_alloc_by_hnb(hnb, context_id, is_ps, cn);
-		OSMO_ASSERT(map);
-		LOGHNB(hnb, DRUA, LOGL_DEBUG, "rua_to_scu() %s to %s, rua_ctx_id %u scu_conn_id %u\n",
-		       cn_domain_indicator_to_str(cN_DomainIndicator), osmo_sccp_addr_dump(remote_addr),
-		       map->rua_ctx_id, map->scu_conn_id);
-	}
-
-	/* add primitive header */
-	switch (type) {
-	case OSMO_SCU_PRIM_N_CONNECT:
-		prim->u.connect.called_addr = *remote_addr;
-		prim->u.connect.calling_addr = cn->gw->sccp.local_addr;
-		prim->u.connect.sccp_class = 2;
-		prim->u.connect.conn_id = map->scu_conn_id;
-		/* Two separate logs because of osmo_sccp_addr_dump(). */
-		LOGHNB(hnb, DRUA, LOGL_DEBUG, "RUA to SCCP N_CONNECT: called_addr:%s\n",
-			osmo_sccp_addr_dump(&prim->u.connect.called_addr));
-		LOGHNB(hnb, DRUA, LOGL_DEBUG, "RUA to SCCP N_CONNECT: calling_addr:%s\n",
-			osmo_sccp_addr_dump(&prim->u.connect.calling_addr));
-		break;
-	case OSMO_SCU_PRIM_N_DATA:
-		prim->u.data.conn_id = map->scu_conn_id;
-		break;
-	case OSMO_SCU_PRIM_N_DISCONNECT:
-		prim->u.disconnect.conn_id = map->scu_conn_id;
-		prim->u.disconnect.cause = cause;
-		release_context_map = true;
-		break;
-	case OSMO_SCU_PRIM_N_UNITDATA:
-		prim->u.unitdata.called_addr = *remote_addr;
-		prim->u.unitdata.calling_addr = cn->gw->sccp.local_addr;
-		/* Two separate logs because of osmo_sccp_addr_dump(). */
-		LOGHNB(hnb, DRUA, LOGL_DEBUG, "RUA to SCCP N_UNITDATA: called_addr:%s\n",
-			osmo_sccp_addr_dump(&prim->u.unitdata.called_addr));
-		LOGHNB(hnb, DRUA, LOGL_DEBUG, "RUA to SCCP N_UNITDATA: calling_addr:%s\n",
-			osmo_sccp_addr_dump(&prim->u.unitdata.calling_addr));
-		break;
-	default:
-		return -EINVAL;
-	}
-
-	/* add optional data section, if needed */
+	/* If there is RANAP data, include it in the msgb. In RUA there is always data in practice, but theoretically it
+	 * could be an empty Connect or Disconnect. */
 	if (data && len) {
-		msg->l2h = msgb_put(msg, len);
-		memcpy(msg->l2h, data, len);
+		/* According to API doc of map_rua_fsm_event: allocate msgb for RANAP data from OTC_SELECT, reserve
+		 * headroom for an osmo_scu_prim. Point l2h at the RANAP data. */
+		ranap_msg = hnbgw_ranap_msg_alloc("RANAP_from_RUA");
+		ranap_msg->l2h = msgb_put(ranap_msg, len);
+		memcpy(ranap_msg->l2h, data, len);
 	}
 
-	rc = osmo_sccp_user_sap_down(cn->sccp_user, &prim->oph);
+	map = context_map_find_by_rua_ctx_id(hnb, context_id, is_ps);
 
-	if (map && release_context_map)
-		context_map_deactivate(map);
+	switch (rua_procedure) {
+	case RUA_ProcedureCode_id_Connect:
+		/* A Connect message can only be the first message for an unused RUA context */
+		if (map) {
+			/* Already established this RUA context. But then how can it be a Connect message. */
+			LOGHNB(hnb, DRUA, LOGL_NOTICE, "rx RUA %s for already active RUA context %u\n",
+			       rua_procedure_code_name(rua_procedure), context_id);
+			return -EINVAL;
+		}
+		/* ok, this RUA context does not exist yet, so create one. */
+		map = create_context_map(hnb, context_id, is_ps, ranap_msg);
+		if (!map) {
+			LOGHNB(hnb, DRUA, LOGL_ERROR,
+			       "Failed to create context map for %s: rx RUA %s with %u bytes RANAP data\n",
+			       is_ps ? "IuPS" : "IuCS", rua_procedure_code_name(rua_procedure), data ? len : 0);
+			rua_tx_disc_conn_fail(hnb, is_ps, context_id);
+			return -EINVAL;
+		}
+		break;
 
-	return rc;
+	case RUA_ProcedureCode_id_Disconnect:
+		/* For RUA Disconnect, do not spam the ERROR log. It is just a stray Disconnect, no harm done.
+		 * Context: some CN are known to rapidly tear down SCCP without waiting for RUA to disconnect gracefully
+		 * (IU Release Complete). Such CN would cause ERROR logging for each and every released context map. */
+		if (!map) {
+			LOGHNB(hnb, DRUA, LOGL_DEBUG, "rx RUA %s for unknown RUA context %u\n",
+			       rua_procedure_code_name(rua_procedure), context_id);
+			return -EINVAL;
+		}
+		break;
+
+	default:
+		/* Any message other than Connect must have a valid RUA context */
+		if (!map) {
+			LOGHNB(hnb, DRUA, LOGL_NOTICE, "rx RUA %s for unknown RUA context %u\n",
+			       rua_procedure_code_name(rua_procedure), context_id);
+			rua_tx_disc_conn_fail(hnb, is_ps, context_id);
+			return -EINVAL;
+		}
+		break;
+	}
+
+	LOG_MAP(map, DRUA, LOGL_DEBUG, "rx RUA %s with %u bytes RANAP data\n",
+		rua_procedure_code_name(rua_procedure), data ? len : 0);
+
+	switch (rua_procedure) {
+
+	case RUA_ProcedureCode_id_Connect:
+		return map_rua_dispatch(map, MAP_RUA_EV_RX_CONNECT, ranap_msg);
+
+	case RUA_ProcedureCode_id_DirectTransfer:
+		return map_rua_dispatch(map, MAP_RUA_EV_RX_DIRECT_TRANSFER, ranap_msg);
+
+	case RUA_ProcedureCode_id_Disconnect:
+		return map_rua_dispatch(map, MAP_RUA_EV_RX_DISCONNECT, ranap_msg);
+
+	default:
+		/* No caller may ever pass a different RUA procedure code */
+		OSMO_ASSERT(false);
+	}
 }
 
 static uint32_t rua_to_scu_cause(RUA_Cause_t *in)
@@ -349,10 +406,12 @@ static int rua_rx_init_connect(struct msgb *msg, ANY_t *in)
 	context_id = asn1bitstr_to_u24(&ies.context_ID);
 
 	LOGHNB(hnb, DRUA, LOGL_DEBUG, "RUA %s Connect.req(ctx=0x%x, %s)\n",
-		cn_domain_indicator_to_str(ies.cN_DomainIndicator), context_id,
+		ranap_domain_name(ies.cN_DomainIndicator), context_id,
 		ies.establishment_Cause == RUA_Establishment_Cause_emergency_call ? "emergency" : "normal");
+	HNBP_CTR_INC(hnb->persistent, ies.cN_DomainIndicator == DOMAIN_PS ?
+		     HNB_CTR_RUA_PS_CONNECT_UL : HNB_CTR_RUA_CS_CONNECT_UL);
 
-	rc = rua_to_scu(hnb, ies.cN_DomainIndicator, OSMO_SCU_PRIM_N_CONNECT,
+	rc = rua_to_scu(hnb, ies.cN_DomainIndicator, RUA_ProcedureCode_id_Connect,
 			context_id, 0, ies.ranaP_Message.buf,
 			ies.ranaP_Message.size);
 
@@ -380,6 +439,8 @@ static int rua_rx_init_disconnect(struct msgb *msg, ANY_t *in)
 
 	LOGHNB(hnb, DRUA, LOGL_DEBUG, "RUA Disconnect.req(ctx=0x%x,cause=%s)\n", context_id,
 		rua_cause_str(&ies.cause));
+	HNBP_CTR_INC(hnb->persistent, ies.cN_DomainIndicator == DOMAIN_PS ?
+		     HNB_CTR_RUA_PS_DISCONNECT_UL : HNB_CTR_RUA_CS_DISCONNECT_UL);
 
 	if (ies.presenceMask & DISCONNECTIES_RUA_RANAP_MESSAGE_PRESENT) {
 		ranap_data = ies.ranaP_Message.buf;
@@ -387,7 +448,7 @@ static int rua_rx_init_disconnect(struct msgb *msg, ANY_t *in)
 	}
 
 	rc = rua_to_scu(hnb, ies.cN_DomainIndicator,
-			OSMO_SCU_PRIM_N_DISCONNECT,
+			RUA_ProcedureCode_id_Disconnect,
 			context_id, scu_cause, ranap_data, ranap_len);
 
 	rua_free_disconnecties(&ies);
@@ -409,10 +470,12 @@ static int rua_rx_init_dt(struct msgb *msg, ANY_t *in)
 	context_id = asn1bitstr_to_u24(&ies.context_ID);
 
 	LOGHNB(hnb, DRUA, LOGL_DEBUG, "RUA Data.req(ctx=0x%x)\n", context_id);
+	HNBP_CTR_INC(hnb->persistent, ies.cN_DomainIndicator == DOMAIN_PS ?
+		     HNB_CTR_RUA_PS_DT_UL : HNB_CTR_RUA_CS_DT_UL);
 
 	rc = rua_to_scu(hnb,
 			ies.cN_DomainIndicator,
-			OSMO_SCU_PRIM_N_DATA,
+			RUA_ProcedureCode_id_DirectTransfer,
 			context_id, 0, ies.ranaP_Message.buf,
 			ies.ranaP_Message.size);
 
@@ -432,6 +495,7 @@ static int rua_rx_init_udt(struct msgb *msg, ANY_t *in)
 		return rc;
 
 	LOGHNB(hnb, DRUA, LOGL_DEBUG, "RUA UData.req()\n");
+	HNBP_CTR_INC(hnb->persistent, HNB_CTR_RUA_UDT_UL);
 
 	/* according tot the spec, we can primarily receive Overload,
 	 * Reset, Reset ACK, Error Indication, reset Resource, Reset
@@ -440,7 +504,7 @@ static int rua_rx_init_udt(struct msgb *msg, ANY_t *in)
 	 * Information Transfer and Uplink Information Trnansfer that we
 	 * can ignore.  In either case, it is RANAP that we need to
 	 * decode... */
-	rc = hnbgw_ranap_rx(msg, ies.ranaP_Message.buf, ies.ranaP_Message.size);
+	rc = hnbgw_ranap_rx_udt_ul(msg, ies.ranaP_Message.buf, ies.ranaP_Message.size);
 	rua_free_connectionlesstransferies(&ies);
 
 	return rc;
@@ -458,6 +522,7 @@ static int rua_rx_init_err_ind(struct msgb *msg, ANY_t *in)
 		return rc;
 
 	LOGHNB(hnb, DRUA, LOGL_ERROR, "RUA UData.ErrorInd(%s)\n", rua_cause_str(&ies.cause));
+	HNBP_CTR_INC(hnb->persistent, HNB_CTR_RUA_ERR_IND);
 
 	rua_free_errorindicationies(&ies);
 	return rc;
@@ -544,6 +609,10 @@ int hnbgw_rua_rx(struct hnb_context *hnb, struct msgb *msg)
 	asn_dec_rval_t dec_ret;
 	int rc;
 
+	/* RUA is only processed after HNB registration, and as soon as the HNB is registered,
+	 * it should have a persistent config associated with it */
+	OSMO_ASSERT(hnb->persistent);
+
 	/* decode and handle to _hnbgw_hnbap_rx() */
 
 	memset(pdu, 0, sizeof(*pdu));
@@ -556,11 +625,7 @@ int hnbgw_rua_rx(struct hnb_context *hnb, struct msgb *msg)
 
 	rc = _hnbgw_rua_rx(msg, pdu);
 
+	ASN_STRUCT_FREE_CONTENTS_ONLY(asn_DEF_RUA_RUA_PDU, pdu);
+
 	return rc;
 }
-
-
-int hnbgw_rua_init(void)
-{
-	return 0;
-}

src/osmo-hnbgw/hnbgw_sccp.c

@@ -0,0 +1,566 @@
+/* hnb-gw specific code for SCCP, ITU Q.711 - Q.714 */
+
+/* (C) 2015 by Harald Welte <laforge@gnumonks.org>
+ * (C) 2025 by sysmocom s.f.m.c. GmbH <info@sysmocom.de>
+ * All Rights Reserved
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include "config.h"
+
+#include <unistd.h>
+#include <errno.h>
+#include <string.h>
+
+#include <osmocom/core/msgb.h>
+#include <osmocom/core/utils.h>
+#include <osmocom/netif/stream.h>
+
+#include <osmocom/sigtran/sccp_sap.h>
+#include <osmocom/sigtran/sccp_helpers.h>
+#include <osmocom/sigtran/protocol/sua.h>
+#include <osmocom/sccp/sccp_types.h>
+
+#include <osmocom/hnbgw/hnbgw_cn.h>
+#include <osmocom/hnbgw/context_map.h>
+#include <osmocom/hnbgw/hnbgw_ranap.h>
+
+/***********************************************************************
+ * Incoming primitives from SCCP User SAP
+ ***********************************************************************/
+
+static bool cnlink_matches(const struct hnbgw_cnlink *cnlink, const struct hnbgw_sccp_user *hsu, const struct osmo_sccp_addr *remote_addr)
+{
+	if (cnlink->hnbgw_sccp_user != hsu)
+		return false;
+	if (osmo_sccp_addr_cmp(&cnlink->remote_addr, remote_addr, OSMO_SCCP_ADDR_T_SSN | OSMO_SCCP_ADDR_T_PC))
+		return false;
+	return true;
+}
+
+static struct hnbgw_cnlink *hnbgw_cnlink_find_by_addr(const struct hnbgw_sccp_user *hsu,
+					       const struct osmo_sccp_addr *remote_addr)
+{
+	struct hnbgw_cnlink *cnlink;
+	llist_for_each_entry(cnlink, &g_hnbgw->sccp.cnpool_iucs->cnlinks, entry) {
+		if (cnlink_matches(cnlink, hsu, remote_addr))
+			return cnlink;
+	}
+	llist_for_each_entry(cnlink, &g_hnbgw->sccp.cnpool_iups->cnlinks, entry) {
+		if (cnlink_matches(cnlink, hsu, remote_addr))
+			return cnlink;
+	}
+	return NULL;
+}
+
+static struct hnbgw_cnlink *cnlink_from_addr(struct hnbgw_sccp_user *hsu, const struct osmo_sccp_addr *calling_addr,
+					     const struct osmo_prim_hdr *oph)
+{
+	struct hnbgw_cnlink *cnlink = NULL;
+	cnlink = hnbgw_cnlink_find_by_addr(hsu, calling_addr);
+	if (!cnlink) {
+		LOG_HSU(hsu, DRANAP, LOGL_ERROR, "Rx from unknown SCCP peer: %s: %s\n",
+			osmo_sccp_inst_addr_name(osmo_ss7_get_sccp(hsu->ss7), calling_addr),
+			osmo_scu_prim_hdr_name_c(OTC_SELECT, oph));
+		return NULL;
+	}
+	return cnlink;
+}
+
+static struct hnbgw_context_map *map_from_conn_id(struct hnbgw_sccp_user *hsu, uint32_t conn_id,
+						  const struct osmo_prim_hdr *oph)
+{
+	struct hnbgw_context_map *map;
+	hash_for_each_possible(hsu->hnbgw_context_map_by_conn_id, map, hnbgw_sccp_user_entry, conn_id) {
+		if (map->scu_conn_id == conn_id)
+			return map;
+	}
+	LOGP(DRANAP, LOGL_ERROR, "Rx for unknown SCCP connection ID: %u: %s\n",
+	     conn_id, osmo_scu_prim_hdr_name_c(OTC_SELECT, oph));
+	return NULL;
+}
+
+static int handle_cn_unitdata(struct hnbgw_sccp_user *hsu,
+			      const struct osmo_scu_unitdata_param *param,
+			      struct osmo_prim_hdr *oph)
+{
+	struct hnbgw_cnlink *cnlink = cnlink_from_addr(hsu, &param->calling_addr, oph);
+	if (!cnlink)
+		return -ENOENT;
+
+	CNLINK_CTR_INC(cnlink, CNLINK_CTR_SCCP_N_UNITDATA_IND);
+
+	if (param->called_addr.ssn != OSMO_SCCP_SSN_RANAP) {
+		LOGP(DCN, LOGL_NOTICE, "N-UNITDATA.ind for unknown SSN %u\n",
+			param->called_addr.ssn);
+		return -1;
+	}
+
+	return hnbgw_ranap_rx_udt_dl(cnlink, param, msgb_l2(oph->msg), msgb_l2len(oph->msg));
+}
+
+static void handle_notice_ind(struct hnbgw_sccp_user *hsu,
+			      const struct osmo_scu_notice_param *param,
+			      const struct osmo_prim_hdr *oph)
+{
+	struct hnbgw_cnlink *cnlink;
+
+	cnlink = cnlink_from_addr(hsu, &param->calling_addr, oph);
+	if (!cnlink) {
+		LOGP(DCN, LOGL_DEBUG, "(calling_addr=%s) N-NOTICE.ind cause=%u='%s' importance=%u didn't match any cnlink, ignoring\n",
+		     osmo_sccp_addr_dump(&param->calling_addr),
+		     param->cause, osmo_sccp_return_cause_name(param->cause),
+		     param->importance);
+		return;
+	}
+
+	LOG_CNLINK(cnlink, DCN, LOGL_NOTICE, "N-NOTICE.ind cause=%u='%s' importance=%u\n",
+		   param->cause, osmo_sccp_return_cause_name(param->cause),
+		   param->importance);
+	CNLINK_CTR_INC(cnlink, CNLINK_CTR_SCCP_N_NOTICE_IND);
+	switch (param->cause) {
+	case SCCP_RETURN_CAUSE_SUBSYSTEM_CONGESTION:
+	case SCCP_RETURN_CAUSE_NETWORK_CONGESTION:
+		/* Transient failures (hopefully), keep going. */
+		return;
+	default:
+		break;
+	}
+
+	/* Messages are not arriving to destination of cnlink. Kick it back to DISC state. */
+	cnlink_set_disconnected(cnlink);
+}
+
+static int handle_cn_conn_conf(struct hnbgw_sccp_user *hsu,
+			       const struct osmo_scu_connect_param *param,
+			       struct osmo_prim_hdr *oph)
+{
+	struct hnbgw_context_map *map;
+
+	map = map_from_conn_id(hsu, param->conn_id, oph);
+	if (!map || !map->cnlink)
+		return -ENOENT;
+
+	LOGP(DCN, LOGL_DEBUG, "handle_cn_conn_conf() conn_id=%d, addrs: called=%s calling=%s responding=%s\n",
+	     param->conn_id,
+	     hnbgw_cnlink_sccp_addr_to_str(map->cnlink, &param->called_addr),
+	     hnbgw_cnlink_sccp_addr_to_str(map->cnlink, &param->calling_addr),
+	     hnbgw_cnlink_sccp_addr_to_str(map->cnlink, &param->responding_addr));
+
+	CNLINK_CTR_INC(map->cnlink, CNLINK_CTR_SCCP_N_CONNECT_CNF);
+
+	map_sccp_dispatch(map, MAP_SCCP_EV_RX_CONNECTION_CONFIRM, oph->msg);
+	return 0;
+}
+
+static int handle_cn_data_ind(struct hnbgw_sccp_user *hsu,
+			      const struct osmo_scu_data_param *param,
+			      struct osmo_prim_hdr *oph)
+{
+	struct hnbgw_context_map *map;
+
+	map = map_from_conn_id(hsu, param->conn_id, oph);
+	if (!map || !map->cnlink)
+		return -ENOENT;
+
+	return map_sccp_dispatch(map, MAP_SCCP_EV_RX_DATA_INDICATION, oph->msg);
+}
+
+static int handle_cn_disc_ind(struct hnbgw_sccp_user *hsu,
+			      const struct osmo_scu_disconn_param *param,
+			      struct osmo_prim_hdr *oph)
+{
+	struct hnbgw_context_map *map;
+	char cause_buf[128];
+
+	map = map_from_conn_id(hsu, param->conn_id, oph);
+	if (!map || !map->cnlink)
+		return -ENOENT;
+
+	LOGP(DCN, LOGL_DEBUG, "handle_cn_disc_ind() conn_id=%u responding_addr=%s cause=%s\n",
+	     param->conn_id,
+	     hnbgw_cnlink_sccp_addr_to_str(map->cnlink, &param->responding_addr),
+	     osmo_sua_sccp_cause_name(param->cause, cause_buf, sizeof(cause_buf)));
+
+	CNLINK_CTR_INC(map->cnlink, CNLINK_CTR_SCCP_N_DISCONNECT_IND);
+
+	return map_sccp_dispatch(map, MAP_SCCP_EV_RX_RELEASED, oph->msg);
+}
+
+static struct hnbgw_cnlink *_cnlink_find_by_remote_pc(struct hnbgw_cnpool *cnpool, struct osmo_ss7_instance *cs7, uint32_t pc)
+{
+	struct hnbgw_cnlink *cnlink;
+	llist_for_each_entry(cnlink, &cnpool->cnlinks, entry) {
+		if (!cnlink->hnbgw_sccp_user)
+			continue;
+		if (cnlink->hnbgw_sccp_user->ss7 != cs7)
+			continue;
+		if ((cnlink->remote_addr.presence & OSMO_SCCP_ADDR_T_PC) == 0)
+			continue;
+		if (cnlink->remote_addr.pc != pc)
+			continue;
+		return cnlink;
+	}
+	return NULL;
+}
+
+/* Find a cnlink by its remote sigtran point code on a given cs7 instance. */
+static struct hnbgw_cnlink *cnlink_find_by_remote_pc(struct osmo_ss7_instance *cs7, uint32_t pc)
+{
+	struct hnbgw_cnlink *cnlink;
+	cnlink = _cnlink_find_by_remote_pc(g_hnbgw->sccp.cnpool_iucs, cs7, pc);
+	if (!cnlink)
+		cnlink = _cnlink_find_by_remote_pc(g_hnbgw->sccp.cnpool_iups, cs7, pc);
+	return cnlink;
+}
+
+static void handle_pcstate_ind(struct hnbgw_sccp_user *hsu, const struct osmo_scu_pcstate_param *pcst)
+{
+	struct hnbgw_cnlink *cnlink;
+	bool connected;
+	bool disconnected;
+	struct osmo_ss7_instance *cs7 = hsu->ss7;
+
+	LOGP(DCN, LOGL_DEBUG, "N-PCSTATE ind: affected_pc=%u=%s sp_status=%s remote_sccp_status=%s\n",
+	     pcst->affected_pc, osmo_ss7_pointcode_print(cs7, pcst->affected_pc),
+	     osmo_sccp_sp_status_name(pcst->sp_status),
+	     osmo_sccp_rem_sccp_status_name(pcst->remote_sccp_status));
+
+	/* If we don't care about that point-code, ignore PCSTATE. */
+	cnlink = cnlink_find_by_remote_pc(cs7, pcst->affected_pc);
+	if (!cnlink)
+		return;
+
+	CNLINK_CTR_INC(cnlink, CNLINK_CTR_SCCP_N_PCSTATE_IND);
+
+	/* See if this marks the point code to have become available, or to have been lost.
+	 *
+	 * I want to detect two events:
+	 * - connection event (both indicators say PC is reachable).
+	 * - disconnection event (at least one indicator says the PC is not reachable).
+	 *
+	 * There are two separate incoming indicators with various possible values -- the incoming events can be:
+	 *
+	 * - neither connection nor disconnection indicated -- just indicating congestion
+	 *   connected == false, disconnected == false --> do nothing.
+	 * - both incoming values indicate that we are connected
+	 *   --> trigger connected
+	 * - both indicate we are disconnected
+	 *   --> trigger disconnected
+	 * - one value indicates 'connected', the other indicates 'disconnected'
+	 *   --> trigger disconnected
+	 *
+	 * Congestion could imply that we're connected, but it does not indicate that a PC's reachability changed, so no need to
+	 * trigger on that.
+	 */
+	connected = false;
+	disconnected = false;
+
+	switch (pcst->sp_status) {
+	case OSMO_SCCP_SP_S_ACCESSIBLE:
+		connected = true;
+		break;
+	case OSMO_SCCP_SP_S_INACCESSIBLE:
+		disconnected = true;
+		break;
+	default:
+	case OSMO_SCCP_SP_S_CONGESTED:
+		/* Neither connecting nor disconnecting */
+		break;
+	}
+
+	switch (pcst->remote_sccp_status) {
+	case OSMO_SCCP_REM_SCCP_S_AVAILABLE:
+		if (!disconnected)
+			connected = true;
+		break;
+	case OSMO_SCCP_REM_SCCP_S_UNAVAILABLE_UNKNOWN:
+	case OSMO_SCCP_REM_SCCP_S_UNEQUIPPED:
+	case OSMO_SCCP_REM_SCCP_S_INACCESSIBLE:
+		disconnected = true;
+		connected = false;
+		break;
+	default:
+	case OSMO_SCCP_REM_SCCP_S_CONGESTED:
+		/* Neither connecting nor disconnecting */
+		break;
+	}
+
+	if (disconnected && cnlink_is_conn_ready(cnlink)) {
+		LOG_CNLINK(cnlink, DCN, LOGL_NOTICE,
+			   "now unreachable: N-PCSTATE ind: pc=%u=%s sp_status=%s remote_sccp_status=%s\n",
+			   pcst->affected_pc, osmo_ss7_pointcode_print(cs7, pcst->affected_pc),
+			   osmo_sccp_sp_status_name(pcst->sp_status),
+			   osmo_sccp_rem_sccp_status_name(pcst->remote_sccp_status));
+		/* A previously usable cnlink has disconnected. Kick it back to DISC state. */
+		cnlink_set_disconnected(cnlink);
+	} else if (connected && !cnlink_is_conn_ready(cnlink)) {
+		LOG_CNLINK(cnlink, DCN, LOGL_NOTICE,
+			   "now available: N-PCSTATE ind: pc=%u=%s sp_status=%s remote_sccp_status=%s\n",
+			   pcst->affected_pc, osmo_ss7_pointcode_print(cs7, pcst->affected_pc),
+			   osmo_sccp_sp_status_name(pcst->sp_status),
+			   osmo_sccp_rem_sccp_status_name(pcst->remote_sccp_status));
+		/* A previously unusable cnlink has become reachable. Trigger immediate RANAP RESET -- we would resend a
+		 * RESET either way, but we might as well do it now to speed up connecting. */
+		cnlink_resend_reset(cnlink);
+	}
+}
+
+/* Entry point for primitives coming up from SCCP User SAP.
+ * Ownership of oph->msg is transferred to us. */
+static int sccp_sap_up(struct osmo_prim_hdr *oph, void *ctx)
+{
+	struct osmo_sccp_user *scu = ctx;
+	struct hnbgw_sccp_user *hsu;
+	struct osmo_scu_prim *prim = (struct osmo_scu_prim *) oph;
+	int rc = 0;
+
+	LOGP(DCN, LOGL_DEBUG, "sccp_sap_up(%s)\n", osmo_scu_prim_name(oph));
+
+	if (!scu) {
+		LOGP(DCN, LOGL_ERROR,
+		     "sccp_sap_up(): NULL osmo_sccp_user, cannot send prim (sap %u prim %u op %d)\n",
+		     oph->sap, oph->primitive, oph->operation);
+		return -1;
+	}
+
+	hsu = osmo_sccp_user_get_priv(scu);
+	if (!hsu) {
+		LOGP(DCN, LOGL_ERROR,
+		     "sccp_sap_up(): NULL hnbgw_sccp_user, cannot send prim (sap %u prim %u op %d)\n",
+		     oph->sap, oph->primitive, oph->operation);
+		return -1;
+	}
+
+	talloc_steal(OTC_SELECT, oph->msg);
+
+	switch (OSMO_PRIM_HDR(oph)) {
+	case OSMO_PRIM(OSMO_SCU_PRIM_N_UNITDATA, PRIM_OP_INDICATION):
+		rc = handle_cn_unitdata(hsu, &prim->u.unitdata, oph);
+		break;
+	case OSMO_PRIM(OSMO_SCU_PRIM_N_NOTICE, PRIM_OP_INDICATION):
+		handle_notice_ind(hsu, &prim->u.notice, oph);
+		break;
+	case OSMO_PRIM(OSMO_SCU_PRIM_N_CONNECT, PRIM_OP_CONFIRM):
+		rc = handle_cn_conn_conf(hsu, &prim->u.connect, oph);
+		break;
+	case OSMO_PRIM(OSMO_SCU_PRIM_N_DATA, PRIM_OP_INDICATION):
+		rc = handle_cn_data_ind(hsu, &prim->u.data, oph);
+		break;
+	case OSMO_PRIM(OSMO_SCU_PRIM_N_DISCONNECT, PRIM_OP_INDICATION):
+		rc = handle_cn_disc_ind(hsu, &prim->u.disconnect, oph);
+		break;
+	case OSMO_PRIM(OSMO_SCU_PRIM_N_PCSTATE, PRIM_OP_INDICATION):
+		handle_pcstate_ind(hsu, &prim->u.pcstate);
+		break;
+
+	default:
+		LOGP(DCN, LOGL_ERROR,
+			"Received unknown prim %u from SCCP USER SAP\n",
+			OSMO_PRIM_HDR(oph));
+		break;
+	}
+
+	return rc;
+}
+
+/***********************************************************************
+ * Submit primitives to SCCP User SAP
+ ***********************************************************************/
+
+int hnbgw_sccp_user_tx_unitdata_req(struct hnbgw_sccp_user *hsu, const struct osmo_sccp_addr *called_addr, struct msgb *ranap_msg)
+{
+	if (!hsu) {
+		LOGP(DCN, LOGL_ERROR, "Failed to send SCCP N-UNITDATA.req: no SCCP User\n");
+		return -1;
+	}
+	OSMO_ASSERT(called_addr);
+	return osmo_sccp_tx_unitdata_msg(hsu->sccp_user,
+					 &hsu->local_addr,
+					 called_addr,
+					 ranap_msg);
+}
+
+int hnbgw_sccp_user_tx_connect_req(struct hnbgw_sccp_user *hsu, const struct osmo_sccp_addr *called_addr, uint32_t scu_conn_id, struct msgb *ranap_msg)
+{
+	struct osmo_scu_prim *prim;
+	int rc;
+
+	if (!hsu) {
+		LOGP(DCN, LOGL_ERROR, "Failed to send SCCP N-CONNECT.req(%u): no SCCP User\n", scu_conn_id);
+		return -1;
+	}
+
+	OSMO_ASSERT(called_addr);
+
+	prim = (struct osmo_scu_prim *)msgb_push(ranap_msg, sizeof(*prim));
+	osmo_prim_init(&prim->oph, SCCP_SAP_USER, OSMO_SCU_PRIM_N_CONNECT, PRIM_OP_REQUEST, ranap_msg);
+	prim->u.connect.called_addr = *called_addr;
+	prim->u.connect.calling_addr = hsu->local_addr;
+	prim->u.connect.sccp_class = 2;
+	prim->u.connect.conn_id = scu_conn_id;
+
+	rc = osmo_sccp_user_sap_down_nofree(hsu->sccp_user, &prim->oph);
+	if (rc)
+		LOG_HSU(hsu, DCN, LOGL_ERROR, "Failed to send SCCP Connection Request to CN\n");
+	return rc;
+}
+
+int hnbgw_sccp_user_tx_data_req(struct hnbgw_sccp_user *hsu, uint32_t scu_conn_id, struct msgb *ranap_msg)
+{
+	struct osmo_scu_prim *prim;
+	int rc;
+
+	if (!hsu) {
+		LOGP(DCN, LOGL_ERROR, "Failed to send SCCP N-DATA.req(%u): no SCCP User\n", scu_conn_id);
+		return -1;
+	}
+
+	prim = (struct osmo_scu_prim *)msgb_push(ranap_msg, sizeof(*prim));
+	osmo_prim_init(&prim->oph, SCCP_SAP_USER, OSMO_SCU_PRIM_N_DATA, PRIM_OP_REQUEST, ranap_msg);
+	prim->u.data.conn_id = scu_conn_id;
+
+	rc = osmo_sccp_user_sap_down_nofree(hsu->sccp_user, &prim->oph);
+	if (rc)
+		LOG_HSU(hsu, DCN, LOGL_ERROR, "Failed to send SCCP N-DATA.req(%u)\n", scu_conn_id);
+	return rc;
+}
+
+int hnbgw_sccp_user_tx_disconnect_req(struct hnbgw_sccp_user *hsu, uint32_t scu_conn_id)
+{
+	int rc;
+
+	if (!hsu) {
+		LOGP(DCN, LOGL_ERROR, "Failed to send SCCP N-DISCONNECT.req(%u): no SCCP User\n", scu_conn_id);
+		return -1;
+	}
+
+	rc = osmo_sccp_tx_disconn(hsu->sccp_user, scu_conn_id, NULL,
+				  SCCP_RELEASE_CAUSE_END_USER_ORIGINATED);
+	if (rc)
+		LOG_HSU(hsu, DCN, LOGL_ERROR, "Failed to send SCCP N-DISCONNECT.req(%u)\n", scu_conn_id);
+	return rc;
+}
+
+/***********************************************************************
+ * struct hnbgw_sccp_user lifecycle:
+ ***********************************************************************/
+
+static int hnbgw_sccp_user_use_cb(struct osmo_use_count_entry *e, int32_t old_use_count, const char *file, int line)
+{
+	struct hnbgw_sccp_user *hsu = e->use_count->talloc_object;
+	int32_t total;
+	int level;
+
+	if (!e->use)
+		return -EINVAL;
+
+	total = osmo_use_count_total(&hsu->use_count);
+
+	if (total == 0
+	    || (total == 1 && old_use_count == 0 && e->count == 1))
+		level = LOGL_INFO;
+	else
+		level = LOGL_DEBUG;
+
+	LOGPSRC(DCN, level, file, line,
+		"%s: %s %s: now used by %s\n",
+		hsu->name,
+		(e->count - old_use_count) > 0 ? "+" : "-",
+		e->use,
+		osmo_use_count_to_str_c(OTC_SELECT, &hsu->use_count));
+
+	if (e->count < 0)
+		return -ERANGE;
+
+	if (total == 0)
+		talloc_free(hsu);
+	return 0;
+}
+
+static int hnbgw_sccp_user_talloc_destructor(struct hnbgw_sccp_user *hsu)
+{
+	if (hsu->sccp_user) {
+		osmo_sccp_user_unbind(hsu->sccp_user);
+		hsu->sccp_user = NULL;
+	}
+	llist_del(&hsu->entry);
+	return 0;
+}
+
+struct hnbgw_sccp_user *hnbgw_sccp_user_alloc(int ss7_id)
+{
+	struct osmo_sccp_instance *sccp;
+	uint32_t local_pc;
+	struct hnbgw_sccp_user *hsu;
+
+	hsu = talloc_zero(g_hnbgw, struct hnbgw_sccp_user);
+	OSMO_ASSERT(hsu);
+	*hsu = (struct hnbgw_sccp_user){
+		.name = talloc_asprintf(hsu, "cs7-%u-sccp-OsmoHNBGW", ss7_id),
+		.use_count = {
+			.talloc_object = hsu,
+			.use_cb = hnbgw_sccp_user_use_cb,
+		},
+	};
+	hash_init(hsu->hnbgw_context_map_by_conn_id);
+	llist_add_tail(&hsu->entry, &g_hnbgw->sccp.users);
+	talloc_set_destructor(hsu, hnbgw_sccp_user_talloc_destructor);
+
+	sccp = osmo_sccp_simple_client_on_ss7_id(g_hnbgw,
+						 ss7_id,
+						 hsu->name,
+						 DEFAULT_PC_HNBGW,
+						 OSMO_SS7_ASP_PROT_M3UA,
+						 0,
+						 "localhost",
+						 -1,
+						 "localhost");
+	if (!sccp) {
+		LOG_HSU(hsu, DCN, LOGL_ERROR, "Failed to configure SCCP on 'cs7 instance %u'\n",
+			ss7_id);
+		goto free_hsu_ret;
+	}
+	hsu->ss7 = osmo_sccp_get_ss7(sccp);
+	LOG_HSU(hsu, DCN, LOGL_NOTICE, "created SCCP instance on cs7 instance %u\n", osmo_ss7_instance_get_id(hsu->ss7));
+
+	/* Bind the SCCP user, using the cs7 instance's default point-code if one is configured, or osmo-hnbgw's default
+	 * local PC. */
+	local_pc = osmo_ss7_instance_get_primary_pc(hsu->ss7);
+	if (!osmo_ss7_pc_is_valid(local_pc))
+		local_pc = DEFAULT_PC_HNBGW;
+
+	LOG_HSU(hsu, DCN, LOGL_DEBUG, "binding OsmoHNBGW user to cs7 instance %u, local PC %u = %s\n",
+		osmo_ss7_instance_get_id(hsu->ss7), local_pc, osmo_ss7_pointcode_print(hsu->ss7, local_pc));
+
+	char *sccp_user_name = talloc_asprintf(hsu, "%s-RANAP", hsu->name);
+	hsu->sccp_user = osmo_sccp_user_bind_pc(sccp, sccp_user_name, sccp_sap_up, OSMO_SCCP_SSN_RANAP, local_pc);
+	talloc_free(sccp_user_name);
+	if (!hsu->sccp_user) {
+		LOG_HSU(hsu, DCN, LOGL_ERROR, "Failed to init SCCP User\n");
+		goto free_hsu_ret;
+	}
+
+	osmo_sccp_make_addr_pc_ssn(&hsu->local_addr, local_pc, OSMO_SCCP_SSN_RANAP);
+	osmo_sccp_user_set_priv(hsu->sccp_user, hsu);
+
+	return hsu;
+
+free_hsu_ret:
+	talloc_free(hsu);
+	return NULL;
+}
+

src/osmo-hnbgw/kpi_dtap.c

@@ -0,0 +1,112 @@
+/* KPI (statistics, counters) at DTAP level */
+/* (C) 2024 by Harald Welte <laforge@osmocom.org>
+ * All Rights Reserved
+ *
+ * SPDX-License-Identifier: AGPL-3.0+
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "config.h"
+
+#include <osmocom/core/utils.h>
+
+#include <osmocom/ranap/ranap_common_ran.h>
+#include <osmocom/gsm/protocol/gsm_04_08.h>
+#include <osmocom/gsm/protocol/gsm_04_08_gprs.h>
+
+#include <osmocom/hnbgw/hnb_persistent.h>
+#include <osmocom/hnbgw/hnbgw.h>
+#include <osmocom/hnbgw/context_map.h>
+#include <osmocom/hnbgw/kpi.h>
+
+/***********************************************************************
+ * DOWNLINK messages
+ ***********************************************************************/
+
+void kpi_dtap_process_dl(struct hnbgw_context_map *map, const uint8_t *buf, unsigned int len,
+			 uint8_t sapi)
+{
+	struct hnb_persistent *hnbp = map->hnb_ctx->persistent;
+	const struct gsm48_hdr *gh = (const struct gsm48_hdr *)buf;
+	if (len < sizeof(*gh))
+		return;
+
+	/* if you make use of any data beyond the fixed-size gsm48_hdr, you must make sure the underlying
+	 * buffer length is actually long enough! */
+
+	if (map->is_ps) {
+		/* Packet Switched Domain (from SGSN) */
+		switch (gsm48_hdr_msg_type(gh)) {
+		case GSM48_MT_GMM_ATTACH_ACK:
+			HNBP_CTR_INC(hnbp, HNB_CTR_DTAP_PS_ATT_ACK);
+			break;
+		case GSM48_MT_GMM_ATTACH_REJ:
+			HNBP_CTR_INC(hnbp, HNB_CTR_DTAP_PS_ATT_REJ);
+			break;
+		case GSM48_MT_GMM_RA_UPD_ACK:
+			HNBP_CTR_INC(hnbp, HNB_CTR_DTAP_PS_RAU_ACK);
+			break;
+		case GSM48_MT_GMM_RA_UPD_REJ:
+			HNBP_CTR_INC(hnbp, HNB_CTR_DTAP_PS_RAU_REJ);
+			break;
+		}
+	} else {
+		/* Circuit Switched Domain (from MSC) */
+		switch (gsm48_hdr_msg_type(gh)) {
+		case GSM48_MT_MM_LOC_UPD_ACCEPT:
+			/* FIXME: many LU are acknwoeldged implicitly with TMSI allocation */
+			HNBP_CTR_INC(hnbp, HNB_CTR_DTAP_CS_LU_ACC);
+			break;
+		case GSM48_MT_MM_LOC_UPD_REJECT:
+			HNBP_CTR_INC(hnbp, HNB_CTR_DTAP_CS_LU_REJ);
+			break;
+		}
+	}
+}
+
+/***********************************************************************
+ * UPLINK messages
+ ***********************************************************************/
+
+void kpi_dtap_process_ul(struct hnbgw_context_map *map, const uint8_t *buf, unsigned int len,
+			 uint8_t sapi)
+{
+	struct hnb_persistent *hnbp = map->hnb_ctx->persistent;
+	const struct gsm48_hdr *gh = (const struct gsm48_hdr *)buf;
+	if (len < sizeof(*gh))
+		return;
+
+	/* if you make use of any data beyond the fixed-size gsm48_hdr, you must make sure the underlying
+	 * buffer length is actually long enough! */
+
+	if (map->is_ps) {
+		/* Packet Switched Domain (to SGSN) */
+		switch (gsm48_hdr_msg_type(gh)) {
+		case GSM48_MT_GMM_ATTACH_REQ:
+			HNBP_CTR_INC(hnbp, HNB_CTR_DTAP_PS_ATT_REQ);
+			break;
+		case GSM48_MT_GMM_RA_UPD_REQ:
+			HNBP_CTR_INC(hnbp, HNB_CTR_DTAP_PS_RAU_REQ);
+			break;
+		}
+	} else {
+		/* Circuit Switched Domain (to MSC) */
+		switch (gsm48_hdr_msg_type(gh)) {
+		case GSM48_MT_MM_LOC_UPD_REQUEST:
+			HNBP_CTR_INC(hnbp, HNB_CTR_DTAP_CS_LU_REQ);
+			break;
+		}
+	}
+}

src/osmo-hnbgw/kpi_ranap.c

@@ -0,0 +1,465 @@
+/* KPI (statistics, counters) at RANAP level */
+/* (C) 2024 by Harald Welte <laforge@osmocom.org>
+ * All Rights Reserved
+ *
+ * SPDX-License-Identifier: AGPL-3.0+
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "config.h"
+
+#include <osmocom/core/utils.h>
+
+#include <osmocom/ranap/ranap_common_ran.h>
+
+#include <osmocom/hnbgw/hnb_persistent.h>
+#include <osmocom/hnbgw/hnbgw_cn.h>
+#include <osmocom/hnbgw/context_map.h>
+#include <osmocom/hnbgw/kpi.h>
+
+const struct value_string hnbgw_rab_state_names[] = {
+	{ RAB_STATE_INACTIVE,	"INACTIVE" },
+	{ RAB_STATE_ACT_REQ,	"ACT_REQ" },
+	{ RAB_STATE_ACTIVE,	"ACTIVE" },
+	{ RAB_STATE_REL_REQ,	"REL_REQ" },
+	{}
+};
+
+/***********************************************************************
+ * DOWNLINK messages
+ ***********************************************************************/
+
+static void kpi_ranap_process_dl_iu_rel_cmd(struct hnbgw_context_map *map, const ranap_message *ranap)
+{
+	struct hnb_persistent *hnbp = map->hnb_ctx->persistent;
+	const RANAP_Cause_t *cause;
+
+	OSMO_ASSERT(ranap->procedureCode == RANAP_ProcedureCode_id_Iu_Release);
+
+	cause = &ranap->msg.iu_ReleaseCommandIEs.cause;
+
+	/* When Iu is released, all RABs are released implicitly */
+	for (unsigned int i = 0; i < ARRAY_SIZE(map->rab_state); i++) {
+		switch (map->rab_state[i]) {
+		case RAB_STATE_ACTIVE:
+			if (cause->present == RANAP_Cause_PR_nAS ||
+			    cause->choice.nAS == RANAP_CauseNAS_normal_release) {
+				HNBP_CTR_INC(hnbp, map->is_ps ? HNB_CTR_RANAP_PS_RAB_REL_IMPLICIT :
+								HNB_CTR_RANAP_CS_RAB_REL_IMPLICIT);
+			} else {
+				HNBP_CTR_INC(hnbp, map->is_ps ? HNB_CTR_RANAP_PS_RAB_REL_IMPLICIT_ABNORMAL :
+								HNB_CTR_RANAP_CS_RAB_REL_IMPLICIT_ABNORMAL);
+			}
+			break;
+		}
+	}
+	/* clear all RAB state */
+	memset(map->rab_state, 0, sizeof(map->rab_state));
+}
+
+static void kpi_ranap_process_dl_rab_ass_req(struct hnbgw_context_map *map, ranap_message *ranap)
+{
+	struct hnb_persistent *hnbp = map->hnb_ctx->persistent;
+	RANAP_RAB_AssignmentRequestIEs_t *ies;
+	int rc;
+
+	OSMO_ASSERT(ranap->procedureCode == RANAP_ProcedureCode_id_RAB_Assignment);
+
+	ies = &ranap->msg.raB_AssignmentRequestIEs;
+
+	if (ies->presenceMask & RAB_ASSIGNMENTREQUESTIES_RANAP_RAB_SETUPORMODIFYLIST_PRESENT) {
+		RANAP_RAB_SetupOrModifyList_t *som_list = &ies->raB_SetupOrModifyList;
+		for (unsigned int i = 0; i < som_list->list.count; i++) {
+			RANAP_ProtocolIE_ContainerPair_t *container_pair = som_list->list.array[i];
+			RANAP_ProtocolIE_FieldPair_t *field_pair = container_pair->list.array[0];
+			RANAP_RAB_SetupOrModifyItemFirst_t _rab_setup_or_modify_item_first = {};
+			RANAP_RAB_SetupOrModifyItemFirst_t *rab_setup_or_modify_item_first = &_rab_setup_or_modify_item_first;
+			uint8_t rab_id;
+
+			if (!field_pair)
+				continue;
+
+			if (field_pair->id != RANAP_ProtocolIE_ID_id_RAB_SetupOrModifyItem)
+				continue;
+
+			rc = ranap_decode_rab_setupormodifyitemfirst(rab_setup_or_modify_item_first, &field_pair->firstValue);
+			if (rc < 0)
+				continue;
+
+			/* RAB-ID is an 8-bit bit-string, so it's the first byte */
+			rab_id = rab_setup_or_modify_item_first->rAB_ID.buf[0];
+
+			/* the only way to distinguish a "setup" from a "modify" is to know which RABs are
+			 * already established. If it's already established, it is a modification; if it's
+			 * new, it is a setup */
+			switch (map->rab_state[rab_id]) {
+			case RAB_STATE_ACTIVE:
+				HNBP_CTR_INC(hnbp, map->is_ps ? HNB_CTR_RANAP_PS_RAB_MOD_REQ :
+								HNB_CTR_RANAP_CS_RAB_MOD_REQ);
+				break;
+			case RAB_STATE_INACTIVE:
+				HNBP_CTR_INC(hnbp, map->is_ps ? HNB_CTR_RANAP_PS_RAB_ACT_REQ :
+								HNB_CTR_RANAP_CS_RAB_ACT_REQ);
+				map->rab_state[rab_id] = RAB_STATE_ACT_REQ;
+				break;
+			default:
+				HNBP_CTR_INC(hnbp, map->is_ps ? HNB_CTR_RANAP_PS_RAB_ACT_REQ_UNEXP :
+								HNB_CTR_RANAP_CS_RAB_ACT_REQ_UNEXP);
+				LOG_MAP(map, DRANAP, LOGL_NOTICE,
+					"Unexpected RAB Activation/Modification Req for RAB in state %s\n",
+					hnbgw_rab_state_name(map->rab_state[rab_id]));
+				break;
+			}
+
+			ASN_STRUCT_FREE_CONTENTS_ONLY(asn_DEF_RANAP_RAB_SetupOrModifyItemFirst, rab_setup_or_modify_item_first);
+		}
+	}
+
+	if (ies->presenceMask & RAB_ASSIGNMENTREQUESTIES_RANAP_RAB_RELEASELIST_PRESENT) {
+		RANAP_RAB_ReleaseList_t *r_list = &ies->raB_ReleaseList;
+		for (unsigned int i = 0; i < r_list->raB_ReleaseList_ies.list.count; i++) {
+			RANAP_IE_t *release_list_ie = r_list->raB_ReleaseList_ies.list.array[i];
+			RANAP_RAB_ReleaseItemIEs_t _rab_rel_item_ies = {};
+			RANAP_RAB_ReleaseItemIEs_t *rab_rel_item_ies = &_rab_rel_item_ies;
+			RANAP_RAB_ReleaseItem_t *rab_rel_item;
+			uint8_t rab_id;
+
+			if (!release_list_ie)
+				continue;
+
+			if (release_list_ie->id != RANAP_ProtocolIE_ID_id_RAB_ReleaseItem)
+				continue;
+
+			rc = ranap_decode_rab_releaseitemies_fromlist(rab_rel_item_ies, &release_list_ie->value);
+			if (rc < 0)
+				continue;
+
+			rab_rel_item = &rab_rel_item_ies->raB_ReleaseItem;
+			/* RAB-ID is an 8-bit bit-string, so it's the first byte */
+			rab_id = rab_rel_item->rAB_ID.buf[0];
+
+			switch (map->rab_state[rab_id]) {
+			case RAB_STATE_ACTIVE:
+				if (rab_rel_item->cause.present == RANAP_Cause_PR_nAS &&
+				    rab_rel_item->cause.choice.nAS == RANAP_CauseNAS_normal_release) {
+					HNBP_CTR_INC(hnbp, map->is_ps ? HNB_CTR_RANAP_PS_RAB_REL_REQ :
+									HNB_CTR_RANAP_CS_RAB_REL_REQ);
+				} else {
+					HNBP_CTR_INC(hnbp, map->is_ps ? HNB_CTR_RANAP_PS_RAB_REL_REQ_ABNORMAL :
+									HNB_CTR_RANAP_CS_RAB_REL_REQ_ABNORMAL);
+				}
+				break;
+			default:
+				HNBP_CTR_INC(hnbp, map->is_ps ? HNB_CTR_RANAP_PS_RAB_REL_REQ_UNEXP :
+								HNB_CTR_RANAP_CS_RAB_REL_REQ_UNEXP);
+				LOG_MAP(map, DRANAP, LOGL_NOTICE,
+					"Unexpected RAB Release Req in state %s\n",
+					hnbgw_rab_state_name(map->rab_state[rab_id]));
+				break;
+			}
+			/* mark that RAB as release requested */
+			map->rab_state[rab_id] = RAB_STATE_REL_REQ;
+
+			ASN_STRUCT_FREE_CONTENTS_ONLY(asn_DEF_RANAP_RAB_ReleaseItem, rab_rel_item_ies);
+		}
+	}
+}
+
+static void kpi_ranap_process_dl_direct_transfer(struct hnbgw_context_map *map, ranap_message *ranap)
+{
+	const RANAP_DirectTransferIEs_t *dt_ies = &ranap->msg.directTransferIEs;
+	uint8_t sapi = 0;
+
+	if (dt_ies->presenceMask & DIRECTTRANSFERIES_RANAP_SAPI_PRESENT) {
+		if (dt_ies->sapi == RANAP_SAPI_sapi_3)
+			sapi = 3;
+	}
+	kpi_dtap_process_dl(map, dt_ies->nas_pdu.buf, dt_ies->nas_pdu.size, sapi);
+}
+
+void kpi_ranap_process_dl(struct hnbgw_context_map *map, ranap_message *ranap)
+{
+	if (map->hnb_ctx == NULL) {
+		/* This can happen if the HNB has disconnected and we are processing downlink messages
+		 * from the CN which were already in flight before the CN side has realized the HNB
+		 * is gone. */
+		return;
+	}
+
+	switch (ranap->procedureCode) {
+	case RANAP_ProcedureCode_id_RAB_Assignment:			/* RAB ASSIGNMENT REQ (8.2) */
+		kpi_ranap_process_dl_rab_ass_req(map, ranap);
+		break;
+	case RANAP_ProcedureCode_id_Iu_Release:
+		kpi_ranap_process_dl_iu_rel_cmd(map, ranap);		/* IU RELEASE CMD (8.5) */
+		break;
+	case RANAP_ProcedureCode_id_DirectTransfer:
+		kpi_ranap_process_dl_direct_transfer(map, ranap);
+		break;
+	default:
+		break;
+	}
+}
+
+/***********************************************************************
+ * UPLINK messages
+ ***********************************************************************/
+
+static void kpi_ranap_process_ul_rab_ass_resp(struct hnbgw_context_map *map, ranap_message *ranap)
+{
+	struct hnb_persistent *hnbp = map->hnb_ctx->persistent;
+	RANAP_RAB_AssignmentResponseIEs_t *ies;
+	int rc;
+
+	OSMO_ASSERT(ranap->procedureCode == RANAP_ProcedureCode_id_RAB_Assignment);
+
+	ies = &ranap->msg.raB_AssignmentResponseIEs;
+
+	if (ies->presenceMask & RAB_ASSIGNMENTRESPONSEIES_RANAP_RAB_SETUPORMODIFIEDLIST_PRESENT) {
+		RANAP_RAB_SetupOrModifiedList_t *som_list = &ies->raB_SetupOrModifiedList;
+		for (unsigned int i = 0; i < som_list->raB_SetupOrModifiedList_ies.list.count; i++) {
+			RANAP_IE_t *som_list_ie = som_list->raB_SetupOrModifiedList_ies.list.array[i];
+			RANAP_RAB_SetupOrModifiedItemIEs_t _rab_som_item_ies = {};
+			RANAP_RAB_SetupOrModifiedItemIEs_t *rab_som_item_ies = &_rab_som_item_ies;
+			RANAP_RAB_SetupOrModifiedItem_t *rab_som_item;
+			uint8_t rab_id;
+
+			if (!som_list_ie)
+				continue;
+
+			if (som_list_ie->id != RANAP_ProtocolIE_ID_id_RAB_SetupOrModifiedItem)
+				continue;
+
+			rc = ranap_decode_rab_setupormodifieditemies_fromlist(rab_som_item_ies, &som_list_ie->value);
+			if (rc < 0)
+				continue;
+
+			rab_som_item = &rab_som_item_ies->raB_SetupOrModifiedItem;
+			/* RAB-ID is an 8-bit bit-string, so it's the first byte */
+			rab_id = rab_som_item->rAB_ID.buf[0];
+
+			/* differentiate modify / activate */
+			switch (map->rab_state[rab_id]) {
+			case RAB_STATE_ACT_REQ:
+				HNBP_CTR_INC(hnbp, map->is_ps ? HNB_CTR_RANAP_PS_RAB_ACT_CNF :
+								HNB_CTR_RANAP_CS_RAB_ACT_CNF);
+				map->rab_state[rab_id] = RAB_STATE_ACTIVE;
+				break;
+			case RAB_STATE_ACTIVE:
+				HNBP_CTR_INC(hnbp, map->is_ps ? HNB_CTR_RANAP_PS_RAB_MOD_CNF :
+								HNB_CTR_RANAP_CS_RAB_MOD_CNF);
+				break;
+			default:
+				HNBP_CTR_INC(hnbp, map->is_ps ? HNB_CTR_RANAP_PS_RAB_ACT_CNF_UNEXP :
+								HNB_CTR_RANAP_CS_RAB_ACT_CNF_UNEXP);
+				LOG_MAP(map, DRANAP, LOGL_NOTICE,
+					"Unexpected RAB Activation/Modification Conf for RAB in state %s\n",
+					hnbgw_rab_state_name(map->rab_state[rab_id]));
+				break;
+			}
+
+			ASN_STRUCT_FREE_CONTENTS_ONLY(asn_DEF_RANAP_RAB_SetupOrModifiedItem, rab_som_item_ies);
+		}
+	}
+
+	if (ies->presenceMask & RAB_ASSIGNMENTRESPONSEIES_RANAP_RAB_RELEASEDLIST_PRESENT) {
+		RANAP_RAB_ReleasedList_t *r_list = &ies->raB_ReleasedList;
+		/* increment number of released RABs, we don't need to do that individually during iteration */
+		for (unsigned int i = 0; i < r_list->raB_ReleasedList_ies.list.count; i++) {
+			RANAP_IE_t *released_list_ie = r_list->raB_ReleasedList_ies.list.array[i];
+			RANAP_RAB_ReleasedItemIEs_t _rab_rel_item_ies = {};
+			RANAP_RAB_ReleasedItemIEs_t *rab_rel_item_ies = &_rab_rel_item_ies;
+			RANAP_RAB_ReleasedItem_t *rab_rel_item;
+			uint8_t rab_id;
+
+			if (!released_list_ie)
+				continue;
+
+			if (released_list_ie->id != RANAP_ProtocolIE_ID_id_RAB_ReleasedItem)
+				continue;
+
+			rc = ranap_decode_rab_releaseditemies_fromlist(rab_rel_item_ies, &released_list_ie->value);
+			if (rc < 0)
+				continue;
+
+			rab_rel_item = &rab_rel_item_ies->raB_ReleasedItem;
+			/* RAB-ID is an 8-bit bit-string, so it's the first byte */
+			rab_id = rab_rel_item->rAB_ID.buf[0];
+
+			switch (map->rab_state[rab_id]) {
+			case RAB_STATE_REL_REQ:
+				HNBP_CTR_INC(hnbp, map->is_ps ? HNB_CTR_RANAP_PS_RAB_REL_CNF :
+								HNB_CTR_RANAP_CS_RAB_REL_CNF);
+				break;
+			default:
+				HNBP_CTR_INC(hnbp, map->is_ps ? HNB_CTR_RANAP_PS_RAB_REL_CNF_UNEXP :
+								HNB_CTR_RANAP_CS_RAB_REL_CNF_UNEXP);
+				LOG_MAP(map, DRANAP, LOGL_NOTICE,
+					"Unexpected RAB Release Conf for RAB in state %s\n",
+					hnbgw_rab_state_name(map->rab_state[rab_id]));
+				break;
+			}
+			/* mark that RAB as released */
+			map->rab_state[rab_id] = RAB_STATE_INACTIVE;
+
+			ASN_STRUCT_FREE_CONTENTS_ONLY(asn_DEF_RANAP_RAB_ReleasedItem, rab_rel_item_ies);
+		}
+	}
+
+	if (ies->presenceMask & RAB_ASSIGNMENTRESPONSEIES_RANAP_RAB_QUEUEDLIST_PRESENT)
+		LOG_MAP(map, DRANAP, LOGL_NOTICE, "RAB Activation has been queued; we don't support KPIs for this\n");
+
+	if (ies->presenceMask & RAB_ASSIGNMENTRESPONSEIES_RANAP_RAB_FAILEDLIST_PRESENT) {
+		RANAP_RAB_FailedList_t *f_list = &ies->raB_FailedList;
+		for (unsigned int i = 0; i < f_list->raB_FailedList_ies.list.count; i++) {
+			RANAP_IE_t *failed_list_ie = f_list->raB_FailedList_ies.list.array[i];
+			RANAP_RAB_FailedItemIEs_t _rab_failed_item_ies = {};
+			RANAP_RAB_FailedItemIEs_t *rab_failed_item_ies = &_rab_failed_item_ies;
+			RANAP_RAB_FailedItem_t *rab_failed_item;
+			uint8_t rab_id;
+
+			if (!failed_list_ie)
+				continue;
+
+			if (failed_list_ie->id != RANAP_ProtocolIE_ID_id_RAB_FailedItem)
+				continue;
+
+			rc = ranap_decode_rab_faileditemies_fromlist(rab_failed_item_ies, &failed_list_ie->value);
+			if (rc < 0)
+				continue;
+
+			rab_failed_item = &rab_failed_item_ies->raB_FailedItem;
+			/* RAB-ID is an 8-bit bit-string, so it's the first byte */
+			rab_id = rab_failed_item->rAB_ID.buf[0];
+
+			/* differentiate modify / activate */
+			switch (map->rab_state[rab_id]) {
+			case RAB_STATE_ACT_REQ:
+				HNBP_CTR_INC(hnbp, map->is_ps ? HNB_CTR_RANAP_PS_RAB_ACT_FAIL :
+								HNB_CTR_RANAP_CS_RAB_ACT_FAIL);
+				map->rab_state[rab_id] = RAB_STATE_INACTIVE;
+				break;
+			case RAB_STATE_ACTIVE:
+				HNBP_CTR_INC(hnbp, map->is_ps ? HNB_CTR_RANAP_PS_RAB_MOD_FAIL :
+								HNB_CTR_RANAP_CS_RAB_MOD_FAIL);
+				// FIXME: does it remain active after modification failure?
+				break;
+			default:
+				HNBP_CTR_INC(hnbp, map->is_ps ? HNB_CTR_RANAP_PS_RAB_ACT_FAIL_UNEXP :
+								HNB_CTR_RANAP_CS_RAB_ACT_FAIL_UNEXP);
+				LOG_MAP(map, DRANAP, LOGL_NOTICE,
+					"Unexpected RAB Activation/Modification Failed for RAB in state %s\n",
+					hnbgw_rab_state_name(map->rab_state[rab_id]));
+				break;
+			}
+
+			ASN_STRUCT_FREE_CONTENTS_ONLY(asn_DEF_RANAP_RAB_FailedItem, rab_failed_item_ies);
+		}
+	}
+
+	if (ies->presenceMask & RAB_ASSIGNMENTRESPONSEIES_RANAP_RAB_RELEASEFAILEDLIST_PRESENT) {
+		RANAP_RAB_ReleaseFailedList_t *rf_list = &ies->raB_ReleaseFailedList;
+		/* increment number of released RABs, we don't need to do that individually during iteration */
+		for (unsigned int i = 0; i < rf_list->raB_FailedList_ies.list.count; i++) {
+			RANAP_IE_t *failed_list_ie = rf_list->raB_FailedList_ies.list.array[i];
+			RANAP_RAB_FailedItemIEs_t _rab_failed_item_ies = {};
+			RANAP_RAB_FailedItemIEs_t *rab_failed_item_ies = &_rab_failed_item_ies;
+			RANAP_RAB_FailedItem_t *rab_failed_item;
+			uint8_t rab_id;
+
+			if (!failed_list_ie)
+				continue;
+
+			if (failed_list_ie->id != RANAP_ProtocolIE_ID_id_RAB_FailedItem)
+				continue;
+
+			rc = ranap_decode_rab_faileditemies_fromlist(rab_failed_item_ies, &failed_list_ie->value);
+			if (rc < 0)
+				continue;
+
+			rab_failed_item = &rab_failed_item_ies->raB_FailedItem;
+			/* RAB-ID is an 8-bit bit-string, so it's the first byte */
+			rab_id = rab_failed_item->rAB_ID.buf[0];
+
+			/* differentiate modify / activate */
+			switch (map->rab_state[rab_id]) {
+			case RAB_STATE_ACT_REQ:
+				HNBP_CTR_INC(hnbp, map->is_ps ? HNB_CTR_RANAP_PS_RAB_REL_FAIL :
+								HNB_CTR_RANAP_CS_RAB_REL_FAIL);
+				map->rab_state[rab_id] = RAB_STATE_INACTIVE;
+				break;
+			case RAB_STATE_ACTIVE:
+				HNBP_CTR_INC(hnbp, map->is_ps ? HNB_CTR_RANAP_PS_RAB_REL_FAIL :
+								HNB_CTR_RANAP_CS_RAB_REL_FAIL);
+				// FIXME: does it remain active after modification failure?
+				break;
+			default:
+				HNBP_CTR_INC(hnbp, map->is_ps ? HNB_CTR_RANAP_PS_RAB_REL_FAIL_UNEXP :
+								HNB_CTR_RANAP_CS_RAB_REL_FAIL_UNEXP);
+				LOG_MAP(map, DRANAP, LOGL_NOTICE,
+					"Unexpected RAB Release Failed for RAB in state %s\n",
+					hnbgw_rab_state_name(map->rab_state[rab_id]));
+				break;
+			}
+
+			ASN_STRUCT_FREE_CONTENTS_ONLY(asn_DEF_RANAP_RAB_FailedItem, rab_failed_item_ies);
+
+		}
+	}
+}
+
+static void kpi_ranap_process_ul_initial_ue(struct hnbgw_context_map *map, ranap_message *ranap)
+{
+	const RANAP_InitialUE_MessageIEs_t *iue_ies = &ranap->msg.initialUE_MessageIEs;
+	kpi_dtap_process_ul(map, iue_ies->nas_pdu.buf, iue_ies->nas_pdu.size, 0);
+}
+
+static void kpi_ranap_process_ul_direct_transfer(struct hnbgw_context_map *map, ranap_message *ranap)
+{
+	const RANAP_DirectTransferIEs_t *dt_ies = &ranap->msg.directTransferIEs;
+	uint8_t sapi = 0;
+
+	if (dt_ies->presenceMask & DIRECTTRANSFERIES_RANAP_SAPI_PRESENT) {
+		if (dt_ies->sapi == RANAP_SAPI_sapi_3)
+			sapi = 3;
+	}
+	kpi_dtap_process_ul(map, dt_ies->nas_pdu.buf, dt_ies->nas_pdu.size, sapi);
+}
+
+void kpi_ranap_process_ul(struct hnbgw_context_map *map, ranap_message *ranap)
+{
+	/* we should never be processing uplink messages from a non-existant HNB */
+	OSMO_ASSERT(map->hnb_ctx);
+
+	switch (ranap->procedureCode) {
+	case RANAP_ProcedureCode_id_RAB_Assignment:			/* RAB ASSIGNMENT REQ (8.2) */
+		kpi_ranap_process_ul_rab_ass_resp(map, ranap);
+		break;
+	case RANAP_ProcedureCode_id_Iu_Release:
+		/* TODO: We might want to parse the list of released RABs here and then mark each of those as
+		 * released.  For now we simply assume that all RABs are released in IU RELEASE during
+		 * processing of the downlink Iu Release Command.  It's not like the RNC/HNB has any way to
+		 * refuse the release anyway. */
+		break;
+	case RANAP_ProcedureCode_id_InitialUE_Message:
+		kpi_ranap_process_ul_initial_ue(map, ranap);
+		break;
+	case RANAP_ProcedureCode_id_DirectTransfer:
+		kpi_ranap_process_ul_direct_transfer(map, ranap);
+		break;
+	default:
+		break;
+	}
+}

src/osmo-hnbgw/mgw_fsm.c

@@ -0,0 +1,958 @@
+/* (C) 2021-2024 by sysmocom s.f.m.c. GmbH <info@sysmocom.de>
+ * All Rights Reserved
+ *
+ * Author: Philipp Maier
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ */
+
+#include <errno.h>
+
+#include <osmocom/core/msgb.h>
+#include <osmocom/core/utils.h>
+#include <osmocom/core/prim.h>
+
+#include <osmocom/core/fsm.h>
+#include <osmocom/core/byteswap.h>
+#include <arpa/inet.h>
+#include <osmocom/core/logging.h>
+#include <osmocom/core/sockaddr_str.h>
+
+#include <osmocom/netif/stream.h>
+
+#include <osmocom/ranap/ranap_common.h>
+#include <osmocom/ranap/ranap_common_cn.h>
+#include <osmocom/ranap/ranap_common_ran.h>
+#include <osmocom/ranap/ranap_msg_factory.h>
+
+#include <osmocom/ranap/ranap_ies_defs.h>
+#include <osmocom/ranap/iu_helpers.h>
+#include <asn1c/asn1helpers.h>
+
+#include <osmocom/hnbgw/hnbgw.h>
+#include <osmocom/hnbgw/context_map.h>
+#include <osmocom/hnbgw/ranap_rab_ass.h>
+
+#include <osmocom/hnbgw/hnbgw_rua.h>
+
+#include <osmocom/core/tdef.h>
+#include <osmocom/hnbgw/tdefs.h>
+#include <osmocom/mgcp_client/mgcp_client_endpoint_fsm.h>
+
+/* NOTE: This implementation can only handle one RAB per context_map (== SCCP connection == RUA connection == UE
+ * context). This simplification was made because usually a voice call will require only one RAB at a time. An exception
+ * may be corner cases like video calls, which we do not support at the moment. */
+
+/* Send Iu Release Request, this is done in erroneous cases from which we cannot recover */
+static void tx_release_req(struct hnbgw_context_map *map)
+{
+	struct msgb *msg;
+	static const struct RANAP_Cause cause = {
+		.present = RANAP_Cause_PR_transmissionNetwork,
+		.choice.transmissionNetwork =
+		    RANAP_CauseTransmissionNetwork_iu_transport_connection_failed_to_establish,
+	};
+
+	msg = ranap_new_msg_iu_rel_req(&cause);
+	msg->l2h = msg->data;
+	talloc_steal(OTC_SELECT, msg);
+	map_sccp_dispatch(map, MAP_SCCP_EV_TX_DATA_REQUEST, msg);
+}
+
+#define S(x)	(1 << (x))
+
+extern int asn1_xer_print;
+
+enum mgw_fsm_event {
+	MGW_EV_MGCP_OK,
+	MGW_EV_MGCP_FAIL,
+	MGW_EV_MGCP_TERM,
+	MGW_EV_RAB_ASS_RESP,
+	MGW_EV_RELEASE,
+};
+
+static const struct value_string mgw_fsm_event_names[] = {
+	OSMO_VALUE_STRING(MGW_EV_MGCP_OK),
+	OSMO_VALUE_STRING(MGW_EV_MGCP_FAIL),
+	OSMO_VALUE_STRING(MGW_EV_MGCP_TERM),
+	OSMO_VALUE_STRING(MGW_EV_RAB_ASS_RESP),
+	OSMO_VALUE_STRING(MGW_EV_RELEASE),
+	{}
+};
+
+enum mgw_fsm_state {
+	MGW_ST_CRCX_HNB,
+	MGW_ST_ASSIGN,
+	MGW_ST_MDCX_HNB,
+	MGW_ST_CRCX_MSC,
+	MGW_ST_ESTABLISHED,
+	MGW_ST_RELEASE,
+	MGW_ST_FAILURE,
+};
+
+struct mgw_fsm_priv {
+	/* Backpointer to HNBGW context */
+	struct hnbgw_context_map *map;
+
+	/* RAB-ID from RANAP RAB AssignmentRequest message */
+	uint8_t rab_id;
+
+	/* Pointers to messages and prim header we take ownership of */
+	ranap_message *ranap_rab_ass_req_message;
+	ranap_message *ranap_rab_ass_resp_message;
+	struct msgb *ranap_rab_ass_resp_msgb;
+	/* IP address contained in ranap_rab_ass_resp_msgb/message: */
+	struct osmo_sockaddr hnb_rtp_addr;
+	/* Number of MDCX transmitted. Used to detect current mgw conn_mode and
+	 * detect modify infinite loops: */
+	unsigned int mdcx_tx_cnt;
+
+	/* MGW context */
+	struct mgcp_client *mgcpc;
+	struct osmo_mgcpc_ep *mgcpc_ep;
+	struct osmo_mgcpc_ep_ci *mgcpc_ep_ci_hnb;
+	struct osmo_mgcpc_ep_ci *mgcpc_ep_ci_msc;
+	struct osmo_sockaddr ci_hnb_crcx_ack_addr;
+	char msc_rtp_addr[INET6_ADDRSTRLEN];
+	uint16_t msc_rtp_port;
+
+	/* Timestamps to track active duration */
+	struct timespec active_start;
+	struct timespec active_stored;
+};
+
+struct osmo_tdef_state_timeout mgw_fsm_timeouts[32] = {
+	[MGW_ST_CRCX_HNB] = {.T = -1001 },
+	[MGW_ST_ASSIGN] = {.T = -1002 },
+	[MGW_ST_MDCX_HNB] = {.T = -1003 },
+	[MGW_ST_CRCX_MSC] = {.T = -1004 },
+};
+
+#define mgw_fsm_state_chg(fi, state) \
+	osmo_tdef_fsm_inst_state_chg(fi, state, mgw_fsm_timeouts, mgw_fsm_T_defs, -1)
+
+static void mgw_fsm_crcx_hnb_onenter(struct osmo_fsm_inst *fi, uint32_t prev_state)
+{
+	struct mgw_fsm_priv *mgw_fsm_priv = fi->priv;
+	struct hnbgw_context_map *map = mgw_fsm_priv->map;
+	struct hnb_context *hnb_ctx = map->hnb_ctx;
+	struct osmo_sockaddr addr;
+	struct osmo_sockaddr_str addr_str;
+	RANAP_RAB_AssignmentRequestIEs_t *ies;
+	const char *epname;
+	struct mgcp_conn_peer mgw_info;
+	int rc;
+
+	LOGPFSML(fi, LOGL_DEBUG, "RAB-AssignmentRequest received, creating HNB side call-leg on MGW...\n");
+
+	/* Parse the RAB Assignment Request now */
+	ies = &mgw_fsm_priv->ranap_rab_ass_req_message->msg.raB_AssignmentRequestIEs;
+	rc = ranap_rab_ass_req_ies_extract_inet_addr(&addr, &mgw_fsm_priv->rab_id, ies, 0);
+	if (rc < 0) {
+		LOGPFSML(fi,  LOGL_ERROR, "Invalid RAB-AssignmentRequest -- abort\n");
+		osmo_fsm_inst_state_chg(fi, MGW_ST_FAILURE, 0, 0);
+		return;
+	}
+
+	rc = osmo_sockaddr_str_from_sockaddr(&addr_str, &addr.u.sas);
+	if (rc < 0) {
+		LOGPFSML(fi, LOGL_ERROR,
+			"Invalid RTP IP-address or port in RAB-AssignmentRequest -- abort\n");
+		osmo_fsm_inst_state_chg(fi, MGW_ST_FAILURE, 0, 0);
+		return;
+	}
+	osmo_strlcpy(mgw_fsm_priv->msc_rtp_addr, addr_str.ip, sizeof(mgw_fsm_priv->msc_rtp_addr));
+	mgw_fsm_priv->msc_rtp_port = addr_str.port;
+
+	mgw_info = (struct mgcp_conn_peer) {
+		.call_id = (map->rua_ctx_id << 8) | mgw_fsm_priv->rab_id,
+		.ptime = 20,
+		.conn_mode = MGCP_CONN_RECV_ONLY,
+	};
+	mgw_info.codecs[0] = CODEC_IUFP;
+	mgw_info.codecs_len = 1;
+
+	/* The HNB IuUP IP address & port is not yet known here (Rx RAB-Ass-Req Tx CRCX (RAN) time):
+	 * Assume and announce "remote IuUP IP address" == "remote Iuh signalling IP address" to the MGW
+	 * here, so that it can most probably select a proper IuUP local IP address to be used from the
+	 * start. In the event we receive a "remote IuUP IP address" != "remote Iuh signalling IP address"
+	 * later on during RAB-Ass-Resp, we'll update IP addr at the MGW through MDCX and if MGW decides
+	 * to use another IuUP local IP address as a result, it will be updated at the HNB through
+	 * RAB-Modify-Req. */
+	if (hnb_ctx && hnb_ctx->conn &&
+	    (rc = osmo_stream_srv_get_fd(hnb_ctx->conn)) >= 0) {
+		if (osmo_sock_get_remote_ip(rc, mgw_info.addr, sizeof(mgw_info.addr)) < 0)
+			LOGPFSML(fi, LOGL_ERROR, "Invalid Iuh IP Address\n");
+	}
+
+	mgw_fsm_priv->mgcpc = mgcp_client_pool_get(g_hnbgw->mgw_pool);
+	if (!mgw_fsm_priv->mgcpc) {
+		LOGPFSML(fi, LOGL_ERROR,
+			 "cannot ensure MGW endpoint -- no MGW configured, check configuration!\n");
+		osmo_fsm_inst_state_chg(fi, MGW_ST_FAILURE, 0, 0);
+		return;
+	}
+	epname = mgcp_client_rtpbridge_wildcard(mgw_fsm_priv->mgcpc);
+	mgw_fsm_priv->mgcpc_ep =
+	    osmo_mgcpc_ep_alloc(fi, MGW_EV_MGCP_TERM, mgw_fsm_priv->mgcpc, mgw_fsm_T_defs, fi->id, "%s", epname);
+	mgw_fsm_priv->mgcpc_ep_ci_hnb = osmo_mgcpc_ep_ci_add(mgw_fsm_priv->mgcpc_ep, "to-HNB");
+
+	osmo_mgcpc_ep_ci_request(mgw_fsm_priv->mgcpc_ep_ci_hnb, MGCP_VERB_CRCX, &mgw_info, fi, MGW_EV_MGCP_OK,
+				 MGW_EV_MGCP_FAIL, NULL);
+}
+
+static void mgw_fsm_crcx_hnb(struct osmo_fsm_inst *fi, uint32_t event, void *data)
+{
+	struct mgw_fsm_priv *mgw_fsm_priv = fi->priv;
+	const struct mgcp_conn_peer *mgw_info;
+	struct osmo_sockaddr_str addr_str;
+	int rc;
+
+	switch (event) {
+	case MGW_EV_MGCP_OK:
+		mgw_info = osmo_mgcpc_ep_ci_get_rtp_info(mgw_fsm_priv->mgcpc_ep_ci_hnb);
+		if (!mgw_info) {
+			LOGPFSML(fi, LOGL_ERROR, "Got no RTP info response from MGW\n");
+			osmo_fsm_inst_state_chg(fi, MGW_ST_FAILURE, 0, 0);
+			return;
+		}
+
+		if (strchr(mgw_info->addr, '.'))
+			addr_str.af = AF_INET;
+		else
+			addr_str.af = AF_INET6;
+		addr_str.port = mgw_info->port;
+		osmo_strlcpy(addr_str.ip, mgw_info->addr, sizeof(addr_str.ip));
+		rc = osmo_sockaddr_str_to_sockaddr(&addr_str, &mgw_fsm_priv->ci_hnb_crcx_ack_addr.u.sas);
+		if (rc < 0) {
+			LOGPFSML(fi, LOGL_ERROR,
+				 "Failed to convert RTP IP-address (%s) and Port (%u) to its binary representation\n",
+				 mgw_info->addr, mgw_info->port);
+			osmo_fsm_inst_state_chg(fi, MGW_ST_FAILURE, 0, 0);
+			return;
+		}
+
+		mgw_fsm_state_chg(fi, MGW_ST_ASSIGN);
+		return;
+	default:
+		OSMO_ASSERT(false);
+	}
+}
+
+static void mgw_fsm_assign_onenter(struct osmo_fsm_inst *fi, uint32_t prev_state)
+{
+	struct mgw_fsm_priv *mgw_fsm_priv = fi->priv;
+	struct hnbgw_context_map *map = mgw_fsm_priv->map;
+	RANAP_RAB_AssignmentRequestIEs_t *ies;
+	struct msgb *msg;
+	int rc;
+
+	ies = &mgw_fsm_priv->ranap_rab_ass_req_message->msg.raB_AssignmentRequestIEs;
+	rc = ranap_rab_ass_req_ies_replace_inet_addr(ies, &mgw_fsm_priv->ci_hnb_crcx_ack_addr, mgw_fsm_priv->rab_id);
+	if (rc < 0) {
+		LOGPFSML(fi, LOGL_ERROR, "Failed to replace RTP IP-address and Port in RAB-AssignmentRequest\n");
+		osmo_fsm_inst_state_chg(fi, MGW_ST_FAILURE, 0, 0);
+		return;
+	}
+
+	msg = ranap_rab_ass_req_encode(ies);
+	if (!msg) {
+		LOGPFSML(fi, LOGL_ERROR, "failed to re-encode RAB-AssignmentRequest message\n");
+		osmo_fsm_inst_state_chg(fi, MGW_ST_FAILURE, 0, 0);
+		return;
+	}
+
+	LOGPFSML(fi, LOGL_DEBUG, "forwarding modified RAB-AssignmentRequest to HNB\n");
+	msg->l2h = msg->data;
+	talloc_steal(OTC_SELECT, msg);
+	map_rua_dispatch(map, MAP_RUA_EV_TX_DIRECT_TRANSFER, msg);
+}
+
+static void mgw_fsm_assign(struct osmo_fsm_inst *fi, uint32_t event, void *data)
+{
+	struct mgw_fsm_priv *mgw_fsm_priv = fi->priv;
+	struct hnbgw_context_map *map = mgw_fsm_priv->map;
+	RANAP_RAB_AssignmentResponseIEs_t *ies;
+	bool rab_failed_at_hnb;
+	struct osmo_sockaddr addr;
+	enum mgw_fsm_state next_st;
+	int rc;
+
+	switch (event) {
+	case MGW_EV_RAB_ASS_RESP:
+		LOGPFSML(fi, LOGL_DEBUG, "RAB-AssignmentResponse received, completing HNB side call-leg on MGW...\n");
+		ies = &mgw_fsm_priv->ranap_rab_ass_resp_message->msg.raB_AssignmentResponseIEs;
+		rc = ranap_rab_ass_resp_ies_extract_inet_addr(&addr, ies, mgw_fsm_priv->rab_id);
+		if (rc < 0) {
+			rab_failed_at_hnb = ranap_rab_ass_resp_ies_check_failure(ies, mgw_fsm_priv->rab_id);
+			if (rab_failed_at_hnb) {
+				struct msgb *msg;
+
+				LOGPFSML(fi, LOGL_ERROR,
+					"The RAB-AssignmentResponse contains a RAB-FailedList, RAB-Assignment (%u) failed.\n",
+					mgw_fsm_priv->rab_id);
+
+				/* Forward the RAB-AssignmentResponse transparently. This will ensure that the MSC
+				 * is informed about the problem. */
+				LOGPFSML(fi, LOGL_DEBUG, "forwarding unmodified RAB-AssignmentResponse to MSC\n");
+
+				msg = mgw_fsm_priv->ranap_rab_ass_resp_msgb;
+				mgw_fsm_priv->ranap_rab_ass_resp_msgb = NULL;
+				talloc_steal(OTC_SELECT, msg);
+
+				rc = map_sccp_dispatch(map, MAP_SCCP_EV_TX_DATA_REQUEST, msg);
+				if (rc < 0) {
+					LOGPFSML(fi, LOGL_DEBUG, "failed to forward RAB-AssignmentResponse message\n");
+					osmo_fsm_inst_state_chg(fi, MGW_ST_FAILURE, 0, 0);
+				}
+
+				/* Even though this is a failure situation, we still release normally as the error is located
+				* at the HNB. */
+				osmo_fsm_inst_state_chg(fi, MGW_ST_RELEASE, 0, 0);
+				return;
+			}
+
+			/* The RAB-ID we are dealing with is not on an FailedList and we were unable to parse the response
+			* normally. This is a situation we cannot recover from. */
+			LOGPFSML(fi, LOGL_ERROR, "Failed to extract RTP IP-address and Port from RAB-AssignmentResponse\n");
+			osmo_fsm_inst_state_chg(fi, MGW_ST_FAILURE, 0, 0);
+			return;
+		}
+
+		/* Break infinite loops modifications between HNB and our MGW: */
+		if (mgw_fsm_priv->mdcx_tx_cnt > 3) {
+			LOGPFSML(fi, LOGL_ERROR, "IuUP addr modification infinite loop detected between HNB and MGW, "
+				 "check your network routing config -- abort!\n");
+			osmo_fsm_inst_state_chg(fi, MGW_ST_RELEASE, 0, 0);
+			return;
+		}
+
+		/* Send at least 1 MDCX in order to change conn_mode to SEND_RECV.
+		 * From there on, MDCX is only needed if HNB IP/Port changed: */
+		if (mgw_fsm_priv->mdcx_tx_cnt == 0 ||
+		    osmo_sockaddr_cmp(&addr, &mgw_fsm_priv->hnb_rtp_addr) != 0) {
+			next_st = MGW_ST_MDCX_HNB;
+		} else {
+			LOGPFSML(fi, LOGL_DEBUG, "RAB-AssignmentResponse received with unchanged IuUP attributes, skipping MDCX...\n");
+			next_st = MGW_ST_CRCX_MSC;
+		}
+		mgw_fsm_priv->hnb_rtp_addr = addr;
+		mgw_fsm_state_chg(fi, next_st);
+		return;
+	default:
+		OSMO_ASSERT(false);
+	}
+}
+
+static void mgw_fsm_mdcx_hnb_onenter(struct osmo_fsm_inst *fi, uint32_t prev_state)
+{
+	struct mgw_fsm_priv *mgw_fsm_priv = fi->priv;
+	struct hnbgw_context_map *map = mgw_fsm_priv->map;
+	struct mgcp_conn_peer mgw_info;
+	struct osmo_sockaddr_str addr_str;
+	int rc;
+
+	mgw_info = (struct mgcp_conn_peer) {
+		.call_id = map->rua_ctx_id,
+		.ptime = 20,
+		.conn_mode = MGCP_CONN_RECV_SEND,
+	};
+	mgw_info.codecs[0] = CODEC_IUFP;
+	mgw_info.codecs_len = 1;
+
+	rc = osmo_sockaddr_str_from_sockaddr(&addr_str, &mgw_fsm_priv->hnb_rtp_addr.u.sas);
+	if (rc < 0) {
+		LOGPFSML(fi, LOGL_ERROR, "Invalid RTP IP-address or Port in RAB-AssignmentResponse\n");
+		osmo_fsm_inst_state_chg(fi, MGW_ST_FAILURE, 0, 0);
+		return;
+	}
+
+	osmo_strlcpy(mgw_info.addr, addr_str.ip, sizeof(mgw_info.addr));
+	mgw_info.port = addr_str.port;
+
+	mgw_fsm_priv->mdcx_tx_cnt++;
+	osmo_mgcpc_ep_ci_request(mgw_fsm_priv->mgcpc_ep_ci_hnb, MGCP_VERB_MDCX, &mgw_info, fi, MGW_EV_MGCP_OK,
+				 MGW_EV_MGCP_FAIL, NULL);
+}
+
+static void mgw_fsm_mdcx_hnb(struct osmo_fsm_inst *fi, uint32_t event, void *data)
+{
+	struct mgw_fsm_priv *mgw_fsm_priv = fi->priv;
+	const struct mgcp_conn_peer *mgw_info;
+	struct osmo_sockaddr_str addr_str;
+	struct osmo_sockaddr addr;
+	int rc;
+
+	switch (event) {
+	case MGW_EV_MGCP_OK:
+		mgw_info = osmo_mgcpc_ep_ci_get_rtp_info(mgw_fsm_priv->mgcpc_ep_ci_hnb);
+		if (!mgw_info) {
+			LOGPFSML(fi, LOGL_ERROR, "Got no RTP info response from MGW\n");
+			osmo_fsm_inst_state_chg(fi, MGW_ST_FAILURE, 0, 0);
+			return;
+		}
+
+		if (strchr(mgw_info->addr, '.'))
+			addr_str.af = AF_INET;
+		else
+			addr_str.af = AF_INET6;
+		addr_str.port = mgw_info->port;
+		osmo_strlcpy(addr_str.ip, mgw_info->addr, sizeof(addr_str.ip));
+		rc = osmo_sockaddr_str_to_sockaddr(&addr_str, &addr.u.sas);
+		if (rc < 0) {
+			LOGPFSML(fi, LOGL_ERROR,
+				 "Failed to convert RTP IP-address (%s) and Port (%u) to its binary representation\n",
+				 mgw_info->addr, mgw_info->port);
+			osmo_fsm_inst_state_chg(fi, MGW_ST_FAILURE, 0, 0);
+			return;
+		}
+
+		if (osmo_sockaddr_cmp(&mgw_fsm_priv->ci_hnb_crcx_ack_addr, &addr) != 0) {
+			char addr_buf[INET6_ADDRSTRLEN + 8];
+			LOGPFSML(fi, LOGL_INFO, "Local MGW IuUP IP address %s changed to %s during MDCX."
+				 " Modifying RAB on HNB.\n",
+				 osmo_sockaddr_to_str(&mgw_fsm_priv->ci_hnb_crcx_ack_addr),
+				 osmo_sockaddr_to_str_buf(addr_buf, sizeof(addr_buf), &addr));
+			/* Modify RAB on the HNB with the new local IuUP address (OS#6127): */
+			mgw_fsm_priv->ci_hnb_crcx_ack_addr = addr;
+			mgw_fsm_state_chg(fi, MGW_ST_ASSIGN);
+			return;
+		}
+
+		mgw_fsm_state_chg(fi, MGW_ST_CRCX_MSC);
+		return;
+	default:
+		OSMO_ASSERT(false);
+	}
+}
+
+static void mgw_fsm_crcx_msc_onenter(struct osmo_fsm_inst *fi, uint32_t prev_state)
+{
+	struct mgw_fsm_priv *mgw_fsm_priv = fi->priv;
+	struct hnbgw_context_map *map = mgw_fsm_priv->map;
+	struct mgcp_conn_peer mgw_info;
+
+	LOGPFSML(fi, LOGL_DEBUG, "creating MSC side call-leg on MGW...\n");
+
+	mgw_info = (struct mgcp_conn_peer) {
+		.call_id = (map->rua_ctx_id << 8) | mgw_fsm_priv->rab_id,
+		.ptime = 20,
+		.port = mgw_fsm_priv->msc_rtp_port,
+	};
+
+	osmo_strlcpy(mgw_info.addr, mgw_fsm_priv->msc_rtp_addr, sizeof(mgw_info.addr));
+	mgw_info.codecs[0] = CODEC_IUFP;
+	mgw_info.codecs_len = 1;
+
+	mgw_fsm_priv->mgcpc_ep_ci_msc = osmo_mgcpc_ep_ci_add(mgw_fsm_priv->mgcpc_ep, "to-MSC");
+	osmo_mgcpc_ep_ci_request(mgw_fsm_priv->mgcpc_ep_ci_msc, MGCP_VERB_CRCX, &mgw_info, fi, MGW_EV_MGCP_OK,
+				 MGW_EV_MGCP_FAIL, NULL);
+}
+
+static void mgw_fsm_crcx_msc(struct osmo_fsm_inst *fi, uint32_t event, void *data)
+{
+	struct mgw_fsm_priv *mgw_fsm_priv = fi->priv;
+	const struct mgcp_conn_peer *mgw_info;
+	struct osmo_sockaddr addr;
+	struct osmo_sockaddr_str addr_str;
+	int rc;
+	int msg_max_len;
+	RANAP_RAB_AssignmentResponseIEs_t *ies;
+
+	switch (event) {
+	case MGW_EV_MGCP_OK:
+		ies = &mgw_fsm_priv->ranap_rab_ass_resp_message->msg.raB_AssignmentResponseIEs;
+
+		mgw_info = osmo_mgcpc_ep_ci_get_rtp_info(mgw_fsm_priv->mgcpc_ep_ci_msc);
+		if (!mgw_info) {
+			LOGPFSML(fi, LOGL_ERROR, "Got no response from MGW\n");
+			osmo_fsm_inst_state_chg(fi, MGW_ST_FAILURE, 0, 0);
+			return;
+		}
+
+		/* Replace RTP IP-Address/Port in ranap message container */
+		if (strchr(mgw_info->addr, '.'))
+			addr_str.af = AF_INET;
+		else
+			addr_str.af = AF_INET6;
+		addr_str.port = mgw_info->port;
+		osmo_strlcpy(addr_str.ip, mgw_info->addr, sizeof(addr_str.ip));
+		rc = osmo_sockaddr_str_to_sockaddr(&addr_str, &addr.u.sas);
+		if (rc < 0) {
+			LOGPFSML(fi, LOGL_ERROR,
+				 "Failed to convert RTP IP-address (%s) and Port (%u) to its binary representation\n",
+				 mgw_info->addr, mgw_info->port);
+			osmo_fsm_inst_state_chg(fi, MGW_ST_FAILURE, 0, 0);
+			return;
+		}
+
+		rc = ranap_rab_ass_resp_ies_replace_inet_addr(ies, &addr, mgw_fsm_priv->rab_id);
+		if (rc < 0) {
+			LOGPFSML(fi, LOGL_ERROR,
+				 "Failed to replace RTP IP-address (%s) and Port (%u) in RAB-AssignmentResponse\n",
+				 mgw_info->addr, mgw_info->port);
+			osmo_fsm_inst_state_chg(fi, MGW_ST_FAILURE, 0, 0);
+			return;
+		}
+
+		/* When the modified ranap message container is re-encoded, the resulting message might be larger then
+		 * the original message. Ensure that there is enough room in l2h to grow. (The current implementation
+		 * should yield a message with the same size, but there is no guarantee for that) */
+		msg_max_len =
+		    msgb_l2len(mgw_fsm_priv->ranap_rab_ass_resp_msgb) +
+		    msgb_tailroom(mgw_fsm_priv->ranap_rab_ass_resp_msgb);
+		rc = msgb_resize_area(mgw_fsm_priv->ranap_rab_ass_resp_msgb,
+				      mgw_fsm_priv->ranap_rab_ass_resp_msgb->l2h,
+				      msgb_l2len(mgw_fsm_priv->ranap_rab_ass_resp_msgb), msg_max_len);
+		OSMO_ASSERT(rc == 0);
+
+		rc = ranap_rab_ass_resp_encode(msgb_l2(mgw_fsm_priv->ranap_rab_ass_resp_msgb),
+					       msgb_l2len(mgw_fsm_priv->ranap_rab_ass_resp_msgb), ies);
+		if (rc < 0) {
+			LOGPFSML(fi, LOGL_ERROR, "failed to re-encode RAB-AssignmentResponse message\n");
+			osmo_fsm_inst_state_chg(fi, MGW_ST_FAILURE, 0, 0);
+			return;
+		}
+
+		/* Resize l2h back to the actual message length */
+		rc = msgb_resize_area(mgw_fsm_priv->ranap_rab_ass_resp_msgb,
+				      mgw_fsm_priv->ranap_rab_ass_resp_msgb->l2h,
+				      msgb_l2len(mgw_fsm_priv->ranap_rab_ass_resp_msgb), rc);
+		OSMO_ASSERT(rc == 0);
+
+		/* When the established state is entered, the modified RAB AssignmentResponse is forwarded to the MSC.
+		 * The call is then established any way may stay for an indefinate amount of time in this state until
+		 * there is an IU Release happening. */
+		osmo_fsm_inst_state_chg(fi, MGW_ST_ESTABLISHED, 0, 0);
+		return;
+	default:
+		OSMO_ASSERT(false);
+	}
+}
+
+static void mgw_fsm_established_onenter(struct osmo_fsm_inst *fi, uint32_t prev_state)
+{
+	struct mgw_fsm_priv *mgw_fsm_priv = fi->priv;
+	struct hnbgw_context_map *map = mgw_fsm_priv->map;
+	struct msgb *ranap_msg;
+	int rc;
+
+	LOGPFSML(fi, LOGL_DEBUG, "forwarding modified RAB-AssignmentResponse to MSC\n");
+
+	ranap_msg = mgw_fsm_priv->ranap_rab_ass_resp_msgb;
+	mgw_fsm_priv->ranap_rab_ass_resp_msgb = NULL;
+	talloc_steal(OTC_SELECT, ranap_msg);
+
+	rc = map_sccp_dispatch(map, MAP_SCCP_EV_TX_DATA_REQUEST, ranap_msg);
+	if (rc < 0) {
+		LOGPFSML(fi, LOGL_DEBUG, "failed to forward RAB-AssignmentResponse message\n");
+		osmo_fsm_inst_state_chg(fi, MGW_ST_FAILURE, 0, 0);
+	}
+
+	LOGPFSML(fi, LOGL_DEBUG, "HNB and MSC side call-legs completed!\n");
+
+	osmo_clock_gettime(CLOCK_MONOTONIC, &mgw_fsm_priv->active_start);
+	mgw_fsm_priv->active_stored = mgw_fsm_priv->active_start;
+}
+
+static void mgw_fsm_release_onenter(struct osmo_fsm_inst *fi, uint32_t prev_state)
+{
+	osmo_fsm_inst_term(fi, OSMO_FSM_TERM_REGULAR, NULL);
+}
+
+static void mgw_fsm_failure_onenter(struct osmo_fsm_inst *fi, uint32_t prev_state)
+{
+	struct mgw_fsm_priv *mgw_fsm_priv = fi->priv;
+	tx_release_req(mgw_fsm_priv->map);
+	osmo_fsm_inst_term(fi, OSMO_FSM_TERM_ERROR, NULL);
+}
+
+static void mgw_fsm_allstate_action(struct osmo_fsm_inst *fi, uint32_t event, void *data)
+{
+	struct mgw_fsm_priv *mgw_fsm_priv = fi->priv;
+
+	switch (event) {
+	case MGW_EV_MGCP_TERM:
+		/* Put MGCP client back into MGW pool */
+		if (mgw_fsm_priv->mgcpc) {
+			mgcp_client_pool_put(mgw_fsm_priv->mgcpc);
+			mgw_fsm_priv->mgcpc = NULL;
+		}
+		mgw_fsm_priv->mgcpc_ep = NULL;
+		LOGPFSML(fi, LOGL_ERROR, "Media gateway failed\n");
+		osmo_fsm_inst_state_chg(fi, MGW_ST_FAILURE, 0, 0);
+		return;
+	case MGW_EV_MGCP_FAIL:
+		LOGPFSML(fi, LOGL_ERROR, "Media gateway failed to switch RTP streams\n");
+		osmo_fsm_inst_state_chg(fi, MGW_ST_FAILURE, 0, 0);
+		return;
+	case MGW_EV_RELEASE:
+		osmo_fsm_inst_state_chg(fi, MGW_ST_RELEASE, 0, 0);
+		return;
+	default:
+		OSMO_ASSERT(false);
+	}
+}
+
+static int mgw_fsm_timer_cb(struct osmo_fsm_inst *fi)
+{
+	osmo_fsm_inst_term(fi, OSMO_FSM_TERM_ERROR, NULL);
+	return 0;
+}
+
+static void mgw_fsm_cleanup(struct osmo_fsm_inst *fi, enum osmo_fsm_term_cause cause)
+{
+	struct mgw_fsm_priv *mgw_fsm_priv = fi->priv;
+	talloc_free(mgw_fsm_priv);
+}
+
+static void mgw_fsm_pre_term(struct osmo_fsm_inst *fi, enum osmo_fsm_term_cause cause)
+{
+	struct mgw_fsm_priv *mgw_fsm_priv = fi->priv;
+	struct hnbgw_context_map *map = mgw_fsm_priv->map;
+
+	if (mgw_fsm_priv->mgcpc_ep) {
+		/* Put MGCP client back into MGW pool */
+		struct mgcp_client *mgcp_client = osmo_mgcpc_ep_client(mgw_fsm_priv->mgcpc_ep);
+		mgcp_client_pool_put(mgcp_client);
+
+		osmo_mgcpc_ep_clear(mgw_fsm_priv->mgcpc_ep);
+		mgw_fsm_priv->mgcpc_ep = NULL;
+	}
+
+	/* Remove FSM from the context map. This will make this FSM unreachable for events coming from outside */
+	map->mgw_fi = NULL;
+}
+
+static const struct osmo_fsm_state mgw_fsm_states[] = {
+	[MGW_ST_CRCX_HNB] = {
+		.name = "MGW_ST_CRCX_HNB",
+		.onenter = mgw_fsm_crcx_hnb_onenter,
+		.action = mgw_fsm_crcx_hnb,
+		.in_event_mask =
+			S(MGW_EV_MGCP_OK),
+		.out_state_mask =
+			S(MGW_ST_ASSIGN) |
+			S(MGW_ST_FAILURE) |
+			S(MGW_ST_RELEASE) |
+			S(MGW_ST_CRCX_HNB),
+	},
+	[MGW_ST_ASSIGN] = {
+		.name = "MGW_ST_ASSIGN",
+		.onenter = mgw_fsm_assign_onenter,
+		.action = mgw_fsm_assign,
+		.in_event_mask = S(MGW_EV_RAB_ASS_RESP),
+		.out_state_mask =
+			S(MGW_ST_MDCX_HNB) |
+			S(MGW_ST_CRCX_MSC) |
+			S(MGW_ST_FAILURE) |
+			S(MGW_ST_RELEASE),
+	},
+	[MGW_ST_MDCX_HNB] = {
+		.name = "MGW_ST_MDCX_HNB",
+		.onenter = mgw_fsm_mdcx_hnb_onenter,
+		.action = mgw_fsm_mdcx_hnb,
+		.in_event_mask =
+			S(MGW_EV_MGCP_OK),
+		.out_state_mask =
+			S(MGW_ST_ASSIGN) |
+			S(MGW_ST_CRCX_MSC) |
+			S(MGW_ST_FAILURE) |
+			S(MGW_ST_RELEASE),
+	},
+	[MGW_ST_CRCX_MSC] = {
+		.name = "MGW_ST_CRCX_MSC",
+		.onenter = mgw_fsm_crcx_msc_onenter,
+		.action = mgw_fsm_crcx_msc,
+		.in_event_mask =
+			S(MGW_EV_MGCP_OK),
+		.out_state_mask =
+			S(MGW_ST_ESTABLISHED) |
+			S(MGW_ST_FAILURE) |
+			S(MGW_ST_RELEASE),
+	},
+	[MGW_ST_ESTABLISHED] = {
+		.name = "MGW_ST_ESTABLISHED",
+		.onenter = mgw_fsm_established_onenter,
+		.in_event_mask = 0,
+		.out_state_mask =
+			S(MGW_ST_FAILURE) |
+			S(MGW_ST_RELEASE),
+	},
+	[MGW_ST_RELEASE] = {
+		.name = "MGW_ST_RELEASE",
+		.onenter = mgw_fsm_release_onenter,
+		.in_event_mask = 0,
+		.out_state_mask = 0,
+	},
+	[MGW_ST_FAILURE] = {
+		.name = "MGW_ST_FAILURE",
+		.onenter = mgw_fsm_failure_onenter,
+		.in_event_mask = 0,
+		.out_state_mask = 0,
+	},
+};
+
+static struct osmo_fsm mgw_fsm = {
+	.name = "mgw",
+	.states = mgw_fsm_states,
+	.num_states = ARRAY_SIZE(mgw_fsm_states),
+	.log_subsys = DMGW,
+	.event_names = mgw_fsm_event_names,
+	.allstate_action = mgw_fsm_allstate_action,
+	.allstate_event_mask = S(MGW_EV_MGCP_TERM) | S(MGW_EV_RELEASE) | S(MGW_EV_MGCP_FAIL),
+	.timer_cb = mgw_fsm_timer_cb,
+	.cleanup = mgw_fsm_cleanup,
+	.pre_term = mgw_fsm_pre_term,
+};
+
+/* The MSC may ask to release a specific RAB within a RAB-AssignmentRequest */
+static int release_mgw_fsm(struct hnbgw_context_map *map, struct msgb *ranap_msg)
+{
+	struct osmo_fsm_inst *fi = map->mgw_fi;
+	int rc;
+
+	/* Forward the unmodifed RAB-AssignmentRequest to HNB, so that the HNB is informed about the RAB release as
+	 * well */
+	LOGPFSML(fi, LOGL_DEBUG, "forwarding unmodified RAB-AssignmentRequest to HNB\n");
+	rc = map_rua_dispatch(map, MAP_RUA_EV_TX_DIRECT_TRANSFER, ranap_msg);
+	if (rc < 0) {
+		LOGPFSML(fi, LOGL_DEBUG, "cannot forward RAB-AssignmentRequest to HNB\n");
+		return -EINVAL;
+	}
+
+	/* Release the FSM normally */
+	osmo_fsm_inst_state_chg(fi, MGW_ST_RELEASE, 0, 0);
+	return 0;
+}
+
+static bool is_rab_ass_without_tli(struct hnbgw_context_map *map, ranap_message *message)
+{
+	RANAP_RAB_AssignmentRequestIEs_t *ies;
+	RANAP_ProtocolIE_ContainerPair_t *protocol_ie_container_pair;
+	RANAP_ProtocolIE_FieldPair_t *protocol_ie_field_pair;
+	RANAP_RAB_SetupOrModifyItemFirst_t _rab_setup_or_modify_item_first = { 0 };
+	RANAP_RAB_SetupOrModifyItemFirst_t *rab_setup_or_modify_item_first = &_rab_setup_or_modify_item_first;
+	int rc;
+	bool ret;
+
+	ies = &message->msg.raB_AssignmentRequestIEs;
+
+	if (!(ies->presenceMask & RAB_ASSIGNMENTREQUESTIES_RANAP_RAB_SETUPORMODIFYLIST_PRESENT))
+		return false;
+
+	/* Detect the end of the list */
+	if (ies->raB_SetupOrModifyList.list.count < 1)
+		return false;
+
+	protocol_ie_container_pair = ies->raB_SetupOrModifyList.list.array[0];
+	protocol_ie_field_pair = protocol_ie_container_pair->list.array[0];
+
+	if (!protocol_ie_field_pair)
+		return false;
+
+	if (protocol_ie_field_pair->id != RANAP_ProtocolIE_ID_id_RAB_SetupOrModifyItem) {
+		RANAP_DEBUG
+		    ("Decoding failed, the protocol IE field-pair is not of type RANAP RAB setup-or-modify-item!\n");
+		return false;
+	}
+
+	rc = ranap_decode_rab_setupormodifyitemfirst(rab_setup_or_modify_item_first,
+						     &protocol_ie_field_pair->firstValue);
+	if (rc < 0)
+		return false;
+
+	ret = rab_setup_or_modify_item_first->transportLayerInformation == NULL;
+	ASN_STRUCT_FREE_CONTENTS_ONLY(asn_DEF_RANAP_RAB_SetupOrModifyItemFirst, rab_setup_or_modify_item_first);
+	return ret;
+}
+
+/* Check if the message contains a RAB-ReleaseItem that matches the RAB-ID that is managed by the given context map */
+static bool is_our_rab_release(struct hnbgw_context_map *map, ranap_message *message)
+{
+	bool rab_release_req;
+	struct osmo_fsm_inst *fi = map->mgw_fi;
+	struct mgw_fsm_priv *mgw_fsm_priv = fi->priv;
+
+	/* Check if the RAB that is handled by this FSM is addressed by the release request */
+	rab_release_req = ranap_rab_ass_req_ies_check_release(&message->msg.raB_AssignmentRequestIEs,
+							      mgw_fsm_priv->rab_id);
+	if (!rab_release_req) {
+		LOGPFSML(map->mgw_fi, LOGL_ERROR, "RAB-AssignmentRequest does not contain any RAB-RelaseItem with RAB-ID %u\n", mgw_fsm_priv->rab_id);
+		return false;
+	}
+	LOGPFSML(map->mgw_fi, LOGL_NOTICE, "MSC asked to release RAB-ID %u\n", mgw_fsm_priv->rab_id);
+
+	return true;
+}
+
+/*! Allocate MGW FSM and handle RANAP RAB AssignmentRequest.
+ *  \param[in] map hnbgw context map that is responsible for this call.
+ *  \param[in] ranap_msg msgb containing RANAP RAB AssignmentRequest at msgb_l2(), allocated in OTC_SELECT.
+ *                       This function may talloc_steal(ranap_msg) to keep it for later.
+ *  \param[in] message decoded RANAP message container, allocated in OTC_SELECT.
+ *                     This function may talloc_steal(message) to keep it for later.
+ *  \returns 0 on success; negative on error. */
+int handle_cs_rab_ass_req(struct hnbgw_context_map *map, struct msgb *ranap_msg, ranap_message *message)
+{
+	static bool initialized = false;
+	struct mgw_fsm_priv *mgw_fsm_priv;
+	char fsm_name[255];
+
+	OSMO_ASSERT(!map->is_ps);
+
+	/* Initialize FSM if not done yet */
+	if (!initialized) {
+		OSMO_ASSERT(osmo_fsm_register(&mgw_fsm) == 0);
+		initialized = true;
+	}
+
+	/* There may be CS RAB Assignment Requests without actual RTP information: after a normal RAB Assignment,
+	 * another RAB Assignment may follow, modifying some RAB parameters. When there is no RTP info in the message,
+	 * there is no RTP to redirect via MGW, hence just forward as-is. */
+	if (is_rab_ass_without_tli(map, message)) {
+		LOG_MAP(map, DCN, LOGL_INFO,
+			"Rx RAB Assignment Request without transportLayerInformation, forwarding as-is\n");
+		return map_rua_dispatch(map, MAP_RUA_EV_TX_DIRECT_TRANSFER, ranap_msg);
+	}
+
+	/* The RTP stream negotiation usually begins with a RAB-AssignmentRequest and ends with an IU-Release, however
+	 * it may also be that the MSC decides to release the RAB with a dedicated RAB-AssignmentRequest that contains
+	 * a ReleaseList. In this case an FSM will already be present. */
+	if (map->mgw_fi) {
+		/* Check if the RAB-AssignmentRequest contains a RAB-ReleaseItem that matches the RAB-ID we are
+		 * managing in this HNBGW context map. */
+		if (is_our_rab_release(map, message))
+			return release_mgw_fsm(map, ranap_msg);
+
+		/* The RAB-ReleaseItem in the incoming message should match the RAB ID we are managing. A mismatch may
+		 * mean that there is an inconsistency between the HNBGW and the MSC state and the MGW FSM on the HNBGW
+		 * side may serve an abandonned connection, which we will now close. However we must also assume that
+		 * the incoming message may still contain a RAB-Assignment for a new RTP stream, so we still must
+		 * continue with the message evaluation. */
+		osmo_fsm_inst_state_chg(map->mgw_fi, MGW_ST_FAILURE, 0, 0);
+		OSMO_ASSERT(map->mgw_fi == NULL);
+	}
+
+	/* This FSM only supports RAB assignments with a single RAB assignment only. This limitation has been taken
+	 * into account under the assumption that voice calls typically require a single RAB only. Nevertheless, we
+	 * will block all incoming RAB assignments that try to assign more (or less) than one RAB. */
+	if (ranap_rab_ass_req_ies_get_count(&message->msg.raB_AssignmentRequestIEs) != 1) {
+		LOG_MAP(map, DMGW, LOGL_ERROR,
+			"%s() RAB-AssignmentRequest with more than one RAB assignment -- abort!\n",
+			__func__);
+		tx_release_req(map);
+		return -1;
+	}
+
+	mgw_fsm_priv = talloc_zero(map, struct mgw_fsm_priv);
+	mgw_fsm_priv->map = map;
+
+	talloc_steal(mgw_fsm_priv, message);
+	mgw_fsm_priv->ranap_rab_ass_req_message = message;
+
+	/* Allocate FSM */
+	snprintf(fsm_name, sizeof(fsm_name), "mgw-fsm-%u-%u", map->rua_ctx_id, mgw_fsm_priv->rab_id);
+	map->mgw_fi = osmo_fsm_inst_alloc(&mgw_fsm, map, mgw_fsm_priv, LOGL_DEBUG, fsm_name);
+
+	/* Start the FSM */
+	mgw_fsm_state_chg(map->mgw_fi, MGW_ST_CRCX_HNB);
+	return 0;
+}
+
+/*! Handlie RANAP RAB AssignmentResponse (deliver message, complete RTP stream switching).
+ *  \param[in] map hnbgw context map that is responsible for this call.
+ *  \param[in] ranap_msg msgb containing RANAP RAB AssignmentResponse at msgb_l2(), allocated in OTC_SELECT.
+ *                       This function may talloc_steal(ranap_msg) to keep it for later.
+ *  \param[in] message decoded RANAP message container, allocated in OTC_SELECT.
+ *                     This function may talloc_steal(message) to keep it for later.
+ *  \returns 0 on success; negative on error. */
+int mgw_fsm_handle_cs_rab_ass_resp(struct hnbgw_context_map *map, struct msgb *ranap_msg, ranap_message *message)
+{
+	struct mgw_fsm_priv *mgw_fsm_priv;
+
+	OSMO_ASSERT(ranap_msg);
+	OSMO_ASSERT(!map->is_ps);
+
+	if (!map->mgw_fi) {
+		/* NOTE: This situation is a corner-case. We may end up here when the co-located MGW caused a problem
+		 * on the way between RANAP RAB Assignment Request and RANAP RAB Assignment Response. */
+
+		LOG_MAP(map, DMGW, LOGL_ERROR,
+			"%s() no MGW fsm -- sending Iu-Release-Request!\n",
+			__func__);
+
+		/* Send a release request, to make sure that the MSC is aware of the problem. */
+		tx_release_req(map);
+		return -1;
+	}
+
+	if (map->mgw_fi->state == MGW_ST_ESTABLISHED) {
+		/* This is a response to a second RAB Assignment Request, which only modified some RAB config on top of
+		 * an earlier RAB Assignment. Just forward the response as-is, we already have our MGW set up and need
+		 * no info from it. (i.e. we don't support modifying the RTP address.) */
+		return map_sccp_dispatch(map, MAP_SCCP_EV_TX_DATA_REQUEST, ranap_msg);
+	}
+
+	mgw_fsm_priv = map->mgw_fi->priv;
+
+	talloc_steal(mgw_fsm_priv, ranap_msg);
+	mgw_fsm_priv->ranap_rab_ass_resp_msgb = ranap_msg;
+
+	talloc_steal(mgw_fsm_priv, message);
+	mgw_fsm_priv->ranap_rab_ass_resp_message = message;
+
+	osmo_fsm_inst_dispatch(map->mgw_fi, MGW_EV_RAB_ASS_RESP, NULL);
+	return 0;
+}
+
+/*! Release the FSM and clear its associated RTP streams.
+ *  \ptmap[in] map hnbgw context map that is responsible for this call.
+ *  \returns 0 on success; negative on error. */
+int mgw_fsm_release(struct hnbgw_context_map *map)
+{
+	OSMO_ASSERT(!map->is_ps);
+
+	if (!map->mgw_fi)
+		return -EINVAL;
+
+	osmo_fsm_inst_dispatch(map->mgw_fi, MGW_EV_RELEASE, NULL);
+	return 0;
+}
+
+/* determine the number of elapsed active RAB milli-seconds since last call */
+uint64_t mgw_fsm_get_elapsed_ms(struct hnbgw_context_map *map, const struct timespec *now)
+{
+	struct mgw_fsm_priv *mgw_fsm_priv;
+	struct timespec elapsed;
+	uint64_t elapsed_ms;
+
+	OSMO_ASSERT(!map->is_ps);
+
+	if (!map->mgw_fi)
+		return 0;
+
+	OSMO_ASSERT(map->mgw_fi->fsm == &mgw_fsm);
+	mgw_fsm_priv = map->mgw_fi->priv;
+
+	/* Ignore RABs whose activation timestamps are not yet set. */
+	if (!timespecisset(&mgw_fsm_priv->active_stored))
+		return 0;
+
+	/* Calculate elapsed time since last storage */
+	timespecsub(now, &mgw_fsm_priv->active_stored, &elapsed);
+	elapsed_ms = elapsed.tv_sec * 1000 + elapsed.tv_nsec / 1000000;
+
+	/* Update storage time */
+	mgw_fsm_priv->active_stored = *now;
+
+	return elapsed_ms;
+}

src/osmo-hnbgw/osmo_hnbgw_main.c

@@ -0,0 +1,377 @@
+/* OsmoHNBGW main routine */
+
+/* (C) 2015-2024 by Harald Welte <laforge@gnumonks.org>
+ * (C) 2016-2023 by sysmocom s.f.m.c. GmbH <info@sysmocom.de>
+ * All Rights Reserved
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include <signal.h>
+#include <getopt.h>
+
+#include "config.h"
+
+#include <osmocom/core/application.h>
+#include <osmocom/core/logging.h>
+#include <osmocom/core/stats.h>
+
+#include <osmocom/vty/vty.h>
+#include <osmocom/vty/command.h>
+#include <osmocom/vty/logging.h>
+#include <osmocom/vty/misc.h>
+#include <osmocom/vty/telnet_interface.h>
+#include <osmocom/vty/ports.h>
+#include <osmocom/vty/stats.h>
+
+#include <osmocom/ctrl/control_vty.h>
+#include <osmocom/ctrl/ports.h>
+
+#include <osmocom/netif/stream.h>
+
+#include <osmocom/sigtran/protocol/m3ua.h>
+
+#include <osmocom/ranap/ranap_common.h>
+
+#include <osmocom/hnbgw/hnb.h>
+#include <osmocom/hnbgw/hnbgw.h>
+#include <osmocom/hnbgw/hnbgw_cn.h>
+#include <osmocom/hnbgw/hnbgw_pfcp.h>
+
+static struct {
+	int daemonize;
+	const char *config_file;
+	bool log_disable_color;
+	bool log_enable_timestamp;
+	int log_level;
+	const char *log_category_mask;
+} hnbgw_cmdline_config = {
+	0,
+	"osmo-hnbgw.cfg",
+	false,
+	false,
+	0,
+	NULL,
+};
+
+static void signal_handler(int signum)
+{
+	fprintf(stdout, "signal %u received\n", signum);
+
+	switch (signum) {
+	case SIGABRT:
+		/* in case of abort, we want to obtain a talloc report and
+		 * then run default SIGABRT handler, who will generate coredump
+		 * and abort the process. abort() should do this for us after we
+		 * return, but program wouldn't exit if an external SIGABRT is
+		 * received.
+		 */
+		talloc_report(tall_vty_ctx, stderr);
+		talloc_report_full(g_hnbgw, stderr);
+		signal(SIGABRT, SIG_DFL);
+		raise(SIGABRT);
+		break;
+	case SIGUSR1:
+		talloc_report(tall_vty_ctx, stderr);
+		talloc_report_full(g_hnbgw, stderr);
+		break;
+	default:
+		break;
+	}
+}
+
+static void print_usage(void)
+{
+	printf("Usage: osmo-hnbgw\n");
+}
+
+static void print_help(void)
+{
+	printf("  -h --help                  This text.\n");
+	printf("  -d option --debug=DHNBAP:DRUA:DRANAP:DMAIN  Enable debugging.\n");
+	printf("  -D --daemonize             Fork the process into a background daemon.\n");
+	printf("  -c --config-file filename  The config file to use.\n");
+	printf("  -s --disable-color\n");
+	printf("  -T --timestamp             Prefix every log line with a timestamp.\n");
+	printf("  -V --version               Print the version of OsmoHNBGW.\n");
+	printf("  -e --log-level number      Set a global loglevel.\n");
+
+	printf("\nVTY reference generation:\n");
+	printf("     --vty-ref-mode MODE        VTY reference generation mode (e.g. 'expert').\n");
+	printf("     --vty-ref-xml              Generate the VTY reference XML output and exit.\n");
+}
+
+static void handle_long_options(const char *prog_name, const int long_option)
+{
+	static int vty_ref_mode = VTY_REF_GEN_MODE_DEFAULT;
+
+	switch (long_option) {
+	case 1:
+		vty_ref_mode = get_string_value(vty_ref_gen_mode_names, optarg);
+		if (vty_ref_mode < 0) {
+			fprintf(stderr, "%s: Unknown VTY reference generation "
+				"mode '%s'\n", prog_name, optarg);
+			exit(2);
+		}
+		break;
+	case 2:
+		fprintf(stderr, "Generating the VTY reference in mode '%s' (%s)\n",
+			get_value_string(vty_ref_gen_mode_names, vty_ref_mode),
+			get_value_string(vty_ref_gen_mode_desc, vty_ref_mode));
+		vty_dump_xml_ref_mode(stdout, (enum vty_ref_gen_mode) vty_ref_mode);
+		exit(0);
+	default:
+		fprintf(stderr, "%s: error parsing cmdline options\n", prog_name);
+		exit(2);
+	}
+}
+
+static void handle_options(int argc, char **argv)
+{
+	while (1) {
+		int option_index = 0, c;
+		static int long_option = 0;
+		static struct option long_options[] = {
+			{"help", 0, 0, 'h'},
+			{"debug", 1, 0, 'd'},
+			{"daemonize", 0, 0, 'D'},
+			{"config-file", 1, 0, 'c'},
+			{"disable-color", 0, 0, 's'},
+			{"timestamp", 0, 0, 'T'},
+			{"version", 0, 0, 'V' },
+			{"log-level", 1, 0, 'e'},
+			{"vty-ref-mode", 1, &long_option, 1},
+			{"vty-ref-xml", 0, &long_option, 2},
+			{0, 0, 0, 0}
+		};
+
+		c = getopt_long(argc, argv, "hd:Dc:sTVe:",
+				long_options, &option_index);
+		if (c == -1)
+			break;
+
+		switch (c) {
+		case 0:
+			handle_long_options(argv[0], long_option);
+			break;
+		case 'h':
+			print_usage();
+			print_help();
+			exit(0);
+		case 's':
+			hnbgw_cmdline_config.log_disable_color = true;
+			break;
+		case 'd':
+			hnbgw_cmdline_config.log_category_mask = optarg;
+			break;
+		case 'D':
+			hnbgw_cmdline_config.daemonize = 1;
+			break;
+		case 'c':
+			hnbgw_cmdline_config.config_file = optarg;
+			break;
+		case 'T':
+			hnbgw_cmdline_config.log_enable_timestamp = true;
+			break;
+		case 'e':
+			hnbgw_cmdline_config.log_level = atoi(optarg);
+			break;
+		case 'V':
+			print_version(1);
+			exit(0);
+			break;
+		default:
+			/* catch unknown options *as well as* missing arguments. */
+			fprintf(stderr, "Error in command line options. Exiting.\n");
+			exit(-1);
+			break;
+		}
+	}
+
+	if (argc > optind) {
+		fprintf(stderr, "Unsupported positional arguments on command line\n");
+		exit(2);
+	}
+}
+
+int main(int argc, char **argv)
+{
+	struct osmo_stream_srv_link *srv;
+	int rc;
+
+	talloc_enable_null_tracking();
+
+	/* g_hnbgw serves as the root talloc ctx, so allocate with NULL parent */
+	g_hnbgw_alloc(NULL);
+	g_hnbgw->config.rnc_id = 23;
+
+	talloc_asn1_ctx = talloc_named_const(g_hnbgw, 1, "asn1_context");
+	msgb_talloc_ctx_init(g_hnbgw, 0);
+
+	rc = osmo_init_logging2(g_hnbgw, &hnbgw_log_info);
+	if (rc < 0)
+		exit(1);
+	log_enable_multithread();
+
+	osmo_stats_init(g_hnbgw);
+	rc = rate_ctr_init(g_hnbgw);
+	if (rc) {
+		LOGP(DMAIN, LOGL_FATAL, "rate_ctr_init() failed with rc=%d\n", rc);
+		exit(1);
+	}
+
+	osmo_fsm_log_timeouts(true);
+
+	rc = osmo_ss7_init();
+	if (rc < 0) {
+		LOGP(DMAIN, LOGL_FATAL, "osmo_ss7_init() failed with rc=%d\n", rc);
+		exit(1);
+	}
+
+	hnbgw_vty_info.tall_ctx = g_hnbgw;
+	vty_init(&hnbgw_vty_info);
+
+	osmo_ss7_vty_init_asp(g_hnbgw);
+	osmo_sccp_vty_init();
+	hnbgw_vty_init();
+	ctrl_vty_init(g_hnbgw);
+	logging_vty_add_cmds();
+	osmo_talloc_vty_add_cmds();
+	osmo_stats_vty_add_cmds();
+
+	/* Handle options after vty_init(), for --version */
+	handle_options(argc, argv);
+
+	rc = vty_read_config_file(hnbgw_cmdline_config.config_file, NULL);
+	if (rc < 0) {
+		LOGP(DMAIN, LOGL_FATAL, "Failed to parse the config file: '%s'\n",
+		     hnbgw_cmdline_config.config_file);
+		return 1;
+	}
+
+	/*
+	 * cmdline options take precedence over config file, but if no options
+	 * were passed we must not override the config file.
+	 */
+	if (hnbgw_cmdline_config.log_disable_color)
+		log_set_use_color(osmo_stderr_target, 0);
+	if (hnbgw_cmdline_config.log_category_mask)
+		log_parse_category_mask(osmo_stderr_target,
+					hnbgw_cmdline_config.log_category_mask);
+	if (hnbgw_cmdline_config.log_enable_timestamp)
+		log_set_print_timestamp(osmo_stderr_target, 1);
+	if (hnbgw_cmdline_config.log_level)
+		log_set_log_level(osmo_stderr_target,
+				  hnbgw_cmdline_config.log_level);
+
+	rc = telnet_init_default(g_hnbgw, g_hnbgw, OSMO_VTY_PORT_HNBGW);
+	if (rc < 0) {
+		perror("Error binding VTY port");
+		exit(1);
+	}
+
+	g_hnbgw->ctrl = ctrl_interface_setup2(g_hnbgw, OSMO_CTRL_PORT_HNBGW, hnb_ctrl_node_lookup,
+					       _LAST_CTRL_NODE_HNB);
+	if (!g_hnbgw->ctrl) {
+		LOGP(DMAIN, LOGL_ERROR, "Failed to create CTRL interface on %s:%u\n",
+		     ctrl_vty_get_bind_addr(), OSMO_CTRL_PORT_HNBGW);
+		exit(1);
+	} else {
+		rc = hnb_ctrl_cmds_install();
+		if (rc) {
+			LOGP(DMAIN, LOGL_ERROR, "Failed to install CTRL interface commands\n");
+			return 2;
+		}
+	}
+
+	ranap_set_log_area(DRANAP);
+
+	LOGP(DHNBAP, LOGL_NOTICE, "Using RNC-Id %u\n", g_hnbgw->config.rnc_id);
+
+	OSMO_ASSERT(g_hnbgw->config.iuh_local_ip);
+	LOGP(DMAIN, LOGL_NOTICE, "Listening for Iuh at %s %d\n",
+	     g_hnbgw->config.iuh_local_ip,
+	     g_hnbgw->config.iuh_local_port);
+	srv = osmo_stream_srv_link_create(g_hnbgw);
+	if (!srv) {
+		perror("cannot create server");
+		exit(1);
+	}
+	osmo_stream_srv_link_set_data(srv, g_hnbgw);
+	osmo_stream_srv_link_set_proto(srv, IPPROTO_SCTP);
+	osmo_stream_srv_link_set_nodelay(srv, true);
+	osmo_stream_srv_link_set_addr(srv, g_hnbgw->config.iuh_local_ip);
+	osmo_stream_srv_link_set_port(srv, g_hnbgw->config.iuh_local_port);
+	osmo_stream_srv_link_set_accept_cb(srv, hnbgw_rua_accept_cb);
+
+	if (osmo_stream_srv_link_open(srv) < 0) {
+		perror("Cannot open server");
+		exit(1);
+	}
+	g_hnbgw->iuh = srv;
+
+	/* Initialize and connect MGCP client. */
+	if (hnbgw_mgw_setup() != 0)
+		return -EINVAL;
+
+#if ENABLE_PFCP
+	/* If UPF is configured, set up PFCP socket and send Association Setup Request to UPF */
+	hnbgw_pfcp_init();
+#endif
+
+	/* If nftables is enabled, initialize the nft table now or fail startup. This is important to immediately let
+	 * the user know if cap_net_admin privileges are missing, and not only when the first hNodeB connects. */
+	if (g_hnbgw->config.nft_kpi.enable) {
+#if ENABLE_NFTABLES
+		nft_kpi_init(g_hnbgw->config.nft_kpi.table_name);
+		/* There is no direct error handling here, because nftables initialization happens asynchronously.
+		 * See nft_kpi.c nft_thread_t2m_cb(), case NFT_THREAD_INIT_TABLE to see what happens when initializing
+		 * nftables failed. */
+#else
+		fprintf(stderr, "ERROR: Cannot enable nft KPI, this binary was built without nftables support\n");
+		exit(1);
+#endif
+	}
+
+	hnbgw_cnpool_start(g_hnbgw->sccp.cnpool_iucs);
+	hnbgw_cnpool_start(g_hnbgw->sccp.cnpool_iups);
+
+	if (hnbgw_cmdline_config.daemonize) {
+		rc = osmo_daemonize();
+		if (rc < 0) {
+			perror("Error during daemonize");
+			exit(1);
+		}
+	}
+
+	signal(SIGABRT, &signal_handler);
+	signal(SIGUSR1, &signal_handler);
+	signal(SIGUSR2, &signal_handler);
+	osmo_init_ignore_signals();
+
+	osmo_fsm_set_dealloc_ctx(OTC_SELECT);
+
+	while (1) {
+		rc = osmo_select_main_ctx(0);
+		if (rc < 0)
+			exit(3);
+	}
+
+	/* not reached */
+#if ENABLE_PFCP
+	hnbgw_pfcp_release();
+#endif
+	exit(0);
+}

src/osmo-hnbgw/ps_rab_ass_fsm.c

@@ -0,0 +1,759 @@
+/* Handle RANAP PS RAB Assignment */
+/* (C) 2022 by sysmocom s.f.m.c. GmbH <info@sysmocom.de>
+ * All Rights Reserved
+ *
+ * Author: Neels Janosch Hofmeyr <nhofmeyr@sysmocom.de>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ */
+
+#include <errno.h>
+
+#include <asn1c/asn1helpers.h>
+
+#include <osmocom/core/msgb.h>
+#include <osmocom/core/utils.h>
+#include <osmocom/core/prim.h>
+
+#include <osmocom/core/fsm.h>
+#include <osmocom/core/byteswap.h>
+#include <arpa/inet.h>
+#include <osmocom/core/logging.h>
+#include <osmocom/core/sockaddr_str.h>
+#include <osmocom/core/tdef.h>
+
+#include <osmocom/ranap/ranap_common.h>
+#include <osmocom/ranap/ranap_common_cn.h>
+#include <osmocom/ranap/ranap_common_ran.h>
+#include <osmocom/ranap/ranap_msg_factory.h>
+
+#include <osmocom/ranap/ranap_ies_defs.h>
+#include <osmocom/ranap/iu_helpers.h>
+
+#include <osmocom/pfcp/pfcp_msg.h>
+#include <osmocom/pfcp/pfcp_endpoint.h>
+#include <osmocom/pfcp/pfcp_cp_peer.h>
+
+#include <osmocom/hnbgw/hnbgw.h>
+#include <osmocom/hnbgw/context_map.h>
+#include <osmocom/hnbgw/ranap_rab_ass.h>
+#include <osmocom/hnbgw/ps_rab_ass_fsm.h>
+#include <osmocom/hnbgw/ps_rab_fsm.h>
+
+#include <osmocom/hnbgw/hnbgw_rua.h>
+
+#include <osmocom/hnbgw/tdefs.h>
+
+#define PORT_GTP1_U 2152
+
+#define LOG_PS_RAB_ASS(RAB_ASS, LOGL, FMT, ARGS...) \
+	LOGPFSML((RAB_ASS) ? (RAB_ASS)->fi : NULL, LOGL, FMT, ##ARGS)
+
+static const struct value_string ps_rab_ass_fsm_event_names[] = {
+	OSMO_VALUE_STRING(PS_RAB_ASS_EV_LOCAL_F_TEIDS_RX),
+	OSMO_VALUE_STRING(PS_RAB_ASS_EV_RAB_ASS_RESP),
+	OSMO_VALUE_STRING(PS_RAB_ASS_EV_RAB_ESTABLISHED),
+	OSMO_VALUE_STRING(PS_RAB_ASS_EV_RAB_RELEASED),
+	OSMO_VALUE_STRING(PS_RAB_ASS_EV_RAB_FAIL),
+	{}
+};
+
+enum ps_rab_ass_state {
+	PS_RAB_ASS_ST_RX_RAB_ASS_MSG,
+	PS_RAB_ASS_ST_WAIT_LOCAL_F_TEIDS,
+	PS_RAB_ASS_ST_RX_RAB_ASS_RESP,
+	PS_RAB_ASS_ST_WAIT_RABS_ESTABLISHED,
+};
+
+/* Represents one RANAP PS RAB Assignment Request and Response dialog.
+ * There may be any number of PS RAB Assignment Requests, each with any number of RABs being established. We need to
+ * manage these asynchronously and flexibly:
+ * - RABs may be assigned in a group and released one by one, or vice versa;
+ * - we can only forward a RAB Assignment Request / Response when all RABs appearing in it have been set up by the UPF.
+ *
+ * This structure manages the RAB Assignment procedures, and the currently set up RABs:
+ *
+ * - hnbgw_context_map
+ *   - .ps_rab_ass_list: list of PS RAB Assignment procedures
+ *     - ps_rab_ass_fsm: one RANAP PS RAB Assignment procedure
+ *     - ...
+ *   - .ps_rab_list: list of individual PS RABs
+ *     - ps_rab_fsm: one GTP mapping with PFCP session to the UPF, for a single RAB
+ *     - ...
+ *
+ * This ps_rab_ass_fsm lives from a received RAB Assignment Request up to the sent RAB Assignment Response; it
+ * deallocates when all the RABs have been set up.
+ *
+ * The ps_rab_ass_fsm sets up ps_rab_fsm instances, which live longer: up until a RAB or conn release is performed.
+ */
+struct ps_rab_ass {
+	struct llist_head entry;
+
+	struct osmo_fsm_inst *fi;
+
+	/* backpointer */
+	struct hnbgw_context_map *map;
+
+	ranap_message *ranap_rab_ass_req_message;
+
+	ranap_message *ranap_rab_ass_resp_message;
+	struct msgb *ranap_rab_ass_resp_msgb;
+
+	/* A RAB Assignment may contain more than one RAB. Each RAB sets up a distinct ps_rab_fsm (aka PFCP session) and
+	 * reports back about local F-TEIDs assigned by the UPF. This gives the nr of RAB events we expect from
+	 * ps_rab_fsms, without iterating the RAB Assignment message every time (minor optimisation). */
+	int rabs_count;
+	int rabs_done_count;
+
+	unsigned int rabs_rel_count;
+	unsigned int rabs_rel_done_count;
+};
+
+struct osmo_tdef_state_timeout ps_rab_ass_fsm_timeouts[32] = {
+	/* PS_RAB_ASS_ST_WAIT_LOCAL_F_TEIDS is terminated by PFCP timeouts via ps_rab_fsm */
+	/* PS_RAB_ASS_ST_WAIT_RABS_ESTABLISHED is terminated by PFCP timeouts via ps_rab_fsm */
+};
+
+#define ps_rab_ass_fsm_state_chg(fi, state) \
+	osmo_tdef_fsm_inst_state_chg(fi, state, ps_rab_ass_fsm_timeouts, hnbgw_T_defs, -1)
+
+static struct osmo_fsm ps_rab_ass_fsm;
+
+static struct ps_rab_ass *ps_rab_ass_alloc(struct hnbgw_context_map *map)
+{
+	struct ps_rab_ass *rab_ass;
+	struct osmo_fsm_inst *fi;
+
+	fi = osmo_fsm_inst_alloc(&ps_rab_ass_fsm, map, map, LOGL_DEBUG, NULL);
+	OSMO_ASSERT(fi);
+	osmo_fsm_inst_update_id_f_sanitize(fi, '-', "%s-RUA-%u", hnb_context_name(map->hnb_ctx), map->rua_ctx_id);
+
+	rab_ass = talloc(fi, struct ps_rab_ass);
+	OSMO_ASSERT(rab_ass);
+	*rab_ass = (struct ps_rab_ass){
+		.fi = fi,
+		.map = map,
+	};
+	fi->priv = rab_ass;
+
+	llist_add_tail(&rab_ass->entry, &map->ps_rab_ass_list);
+	return rab_ass;
+}
+
+static void ps_rab_ass_failure(struct ps_rab_ass *rab_ass)
+{
+	LOG_PS_RAB_ASS(rab_ass, LOGL_ERROR, "PS RAB Assignment failed\n");
+
+	/* TODO: send unsuccessful RAB Assignment Response to Core? */
+	/* TODO: remove RAB from Access? */
+
+	osmo_fsm_inst_term(rab_ass->fi, OSMO_FSM_TERM_REGULAR, NULL);
+}
+
+/* Add a single RAB from a RANAP PS RAB Assignment Request's list of RABs */
+static int ps_rab_setup_core_remote(struct ps_rab_ass *rab_ass, RANAP_ProtocolIE_FieldPair_t *protocol_ie_field_pair)
+{
+	struct hnbgw_context_map *map = rab_ass->map;
+	uint8_t rab_id;
+	struct addr_teid f_teid = {};
+	bool use_x213_nsap;
+	struct ps_rab *rab;
+
+	RANAP_RAB_SetupOrModifyItemFirst_t first;
+	RANAP_TransportLayerAddress_t *transp_layer_addr;
+	RANAP_TransportLayerInformation_t *tli;
+	int rc;
+
+	if (protocol_ie_field_pair->id != RANAP_ProtocolIE_ID_id_RAB_SetupOrModifyItem)
+		return -1;
+
+	/* Extract information about the GTP Core side */
+	rc = ranap_decode_rab_setupormodifyitemfirst(&first,
+						     &protocol_ie_field_pair->firstValue);
+	if (rc < 0)
+		goto error_exit;
+
+	rab_id = first.rAB_ID.buf[0];
+
+	/* Decode GTP endpoint IP-Address */
+	tli = first.transportLayerInformation;
+	transp_layer_addr = &tli->transportLayerAddress;
+	rc = ranap_transp_layer_addr_decode2(&f_teid.addr, &use_x213_nsap, transp_layer_addr);
+	if (rc < 0)
+		goto error_exit;
+	osmo_sockaddr_set_port(&f_teid.addr.u.sa, PORT_GTP1_U);
+
+	/* Decode the GTP remote TEID */
+	if (tli->iuTransportAssociation.present != RANAP_IuTransportAssociation_PR_gTP_TEI) {
+		rc = -1;
+		goto error_exit;
+	}
+	f_teid.teid = osmo_load32be(tli->iuTransportAssociation.choice.gTP_TEI.buf);
+	f_teid.present = true;
+
+	rab_ass->rabs_count++;
+	rab = ps_rab_start(map, rab_id, &f_teid, use_x213_nsap, rab_ass->fi);
+	if (!rab) {
+		rc = -1;
+		goto error_exit;
+	}
+	rc = 0;
+
+error_exit:
+	ASN_STRUCT_FREE_CONTENTS_ONLY(asn_DEF_RANAP_RAB_SetupOrModifyItemFirst, &first);
+	return rc;
+}
+
+/*! Allocate ps_rab_ass_fsm and handle PS RANAP RAB AssignmentRequest.
+ *  \param[in] map hnbgw context map that is responsible for this conn.
+ *  \param[in] ranap_msg msgb containing RANAP RAB AssignmentRequest at msgb_l2(), allocated in OTC_SELECT.
+ *                       This function may talloc_steal(ranap_msg) to keep it for later.
+ *  \param[in] message decoded RANAP message container, allocated in OTC_SELECT.
+ *                     This function may talloc_steal(message) to keep it for later.
+ *  \returns 0 on success; negative on error. */
+int hnbgw_gtpmap_rx_rab_ass_req(struct hnbgw_context_map *map, struct msgb *ranap_msg, ranap_message *message)
+{
+	RANAP_RAB_AssignmentRequestIEs_t *ies = &message->msg.raB_AssignmentRequestIEs;
+	int i;
+	struct ps_rab_ass *rab_ass;
+
+	rab_ass = ps_rab_ass_alloc(map);
+	talloc_steal(rab_ass, message);
+	rab_ass->ranap_rab_ass_req_message = message;
+	/* Now rab_ass owns message and will clean it up */
+
+	if (!osmo_pfcp_cp_peer_is_associated(g_hnbgw->pfcp.cp_peer)) {
+		LOG_MAP(map, DLPFCP, LOGL_ERROR, "PFCP is not associated, cannot set up GTP mapping\n");
+		goto no_rab;
+	}
+
+	/* setup-or-modify list */
+	if (ies->presenceMask & RAB_ASSIGNMENTREQUESTIES_RANAP_RAB_SETUPORMODIFYLIST_PRESENT) {
+		/* Multiple RABs may be set up, assemble in list map->ps_rab_list. */
+		for (i = 0; i < ies->raB_SetupOrModifyList.list.count; i++) {
+			RANAP_ProtocolIE_ContainerPair_t *protocol_ie_container_pair;
+			RANAP_ProtocolIE_FieldPair_t *protocol_ie_field_pair;
+
+			protocol_ie_container_pair = ies->raB_SetupOrModifyList.list.array[i];
+			protocol_ie_field_pair = protocol_ie_container_pair->list.array[0];
+			if (!protocol_ie_field_pair)
+				goto no_rab;
+			if (protocol_ie_field_pair->id != RANAP_ProtocolIE_ID_id_RAB_SetupOrModifyItem)
+				goto no_rab;
+
+			if (ps_rab_setup_core_remote(rab_ass, protocol_ie_field_pair))
+				goto no_rab;
+		}
+	}
+
+	/* Note: ReleaseList is handled at RAB Assign Response time. */
+
+	if (rab_ass->rabs_count > 0) {
+		/* Got all RABs' state and their Core side GTP info in map->ps_rab_list.
+		 * For each, a ps_rab_fsm has been started and each will call back with
+		 * PS_RAB_ASS_EV_LOCAL_F_TEIDS_RX or PS_RAB_ASS_EV_RAB_FAIL. */
+		return ps_rab_ass_fsm_state_chg(rab_ass->fi, PS_RAB_ASS_ST_WAIT_LOCAL_F_TEIDS);
+	}
+
+	/* No Setup-or-modify, only Release RABs. Forward the message as is,
+	 * RABs will be released at RAB ASS Response time. */
+	map_rua_dispatch(map, MAP_RUA_EV_TX_DIRECT_TRANSFER, ranap_msg);
+	osmo_fsm_inst_term(rab_ass->fi, OSMO_FSM_TERM_REGULAR, NULL);
+	return 0;
+no_rab:
+	ps_rab_ass_failure(rab_ass);
+	return -1;
+}
+
+static void ps_rab_ass_req_check_local_f_teids(struct ps_rab_ass *rab_ass);
+
+static void ps_rab_ass_fsm_wait_local_f_teids(struct osmo_fsm_inst *fi, uint32_t event, void *data)
+{
+	struct ps_rab_ass *rab_ass = fi->priv;
+
+	switch (event) {
+	case PS_RAB_ASS_EV_LOCAL_F_TEIDS_RX:
+		rab_ass->rabs_done_count++;
+		if (rab_ass->rabs_done_count < rab_ass->rabs_count) {
+			/* some RABs are still pending, postpone going through the message until all are done. */
+			return;
+		}
+		ps_rab_ass_req_check_local_f_teids(rab_ass);
+		return;
+
+	case PS_RAB_ASS_EV_RAB_FAIL:
+		ps_rab_ass_failure(rab_ass);
+		return;
+
+	default:
+		OSMO_ASSERT(false);
+	}
+}
+
+/* See whether all information is in so that we can forward the modified RAB Assignment Request to RUA. */
+static void ps_rab_ass_req_check_local_f_teids(struct ps_rab_ass *rab_ass)
+{
+	struct ps_rab *rab = NULL;
+	RANAP_RAB_AssignmentRequestIEs_t *ies = &rab_ass->ranap_rab_ass_req_message->msg.raB_AssignmentRequestIEs;
+	int i;
+	struct msgb *msg;
+
+	/* Go through all RABs in the RAB Assignment Request message and replace with the F-TEID that the UPF assigned,
+	 * verifying that we indeed have local F-TEIDs for all RABs contained in this message. */
+	for (i = 0; i < ies->raB_SetupOrModifyList.list.count; i++) {
+		RANAP_ProtocolIE_ContainerPair_t *protocol_ie_container_pair;
+		RANAP_ProtocolIE_FieldPair_t *protocol_ie_field_pair;
+		RANAP_RAB_SetupOrModifyItemFirst_t first;
+		uint8_t rab_id;
+		int rc;
+
+		protocol_ie_container_pair = ies->raB_SetupOrModifyList.list.array[i];
+		protocol_ie_field_pair = protocol_ie_container_pair->list.array[0];
+		if (!protocol_ie_field_pair)
+			continue;
+		if (protocol_ie_field_pair->id != RANAP_ProtocolIE_ID_id_RAB_SetupOrModifyItem)
+			continue;
+
+		/* Get to the information about the GTP Core side */
+		rc = ranap_decode_rab_setupormodifyitemfirst(&first,
+							     &protocol_ie_field_pair->firstValue);
+		if (rc < 0)
+			goto continue_cleanloop;
+
+		rab_id = first.rAB_ID.buf[0];
+
+		/* Find struct ps_rab for this rab_id */
+		rab = ps_rab_get(rab_ass->map, rab_id);
+		if (!rab || !rab->access.local.present) {
+			/* Not ready to send on the RAB Assignment Request to RUA, a local F-TEID is missing. */
+			ASN_STRUCT_FREE_CONTENTS_ONLY(asn_DEF_RANAP_RAB_SetupOrModifyItemFirst, &first);
+			return;
+		}
+
+		/* Replace GTP endpoint */
+		ASN_STRUCT_FREE(asn_DEF_RANAP_TransportLayerInformation, first.transportLayerInformation);
+		first.transportLayerInformation = ranap_new_transp_info_gtp(&rab->access.local.addr,
+									    rab->access.local.teid,
+									    rab->core.use_x213_nsap);
+
+		/* Reencode to update transport-layer-information */
+		rc = ANY_fromType_aper(&protocol_ie_field_pair->firstValue, &asn_DEF_RANAP_RAB_SetupOrModifyItemFirst,
+				       &first);
+		if (rc < 0)
+			LOG_PS_RAB_ASS(rab_ass, LOGL_ERROR, "Re-encoding RANAP PS RAB Assignment Request failed\n");
+continue_cleanloop:
+		ASN_STRUCT_FREE_CONTENTS_ONLY(asn_DEF_RANAP_RAB_SetupOrModifyItemFirst, &first);
+	}
+
+	if (!rab) {
+		LOG_PS_RAB_ASS(rab_ass, LOGL_ERROR, "Lookup PS RAB Assignment Request failed\n");
+		ps_rab_ass_failure(rab_ass);
+		return;
+	}
+
+	/* Send the modified RAB Assignment Request to the hNodeB, wait for the RAB Assignment Response */
+	msg = ranap_rab_ass_req_encode(ies);
+	if (!msg) {
+		LOG_PS_RAB_ASS(rab_ass, LOGL_ERROR, "Re-encoding RANAP PS RAB Assignment Request failed\n");
+		ps_rab_ass_failure(rab_ass);
+		return;
+	}
+	talloc_steal(OTC_SELECT, msg);
+	msg->l2h = msg->data;
+	map_rua_dispatch(rab->map, MAP_RUA_EV_TX_DIRECT_TRANSFER, msg);
+
+	/* The request message has been forwarded. The response will be handled by a new FSM instance.
+	 * We are done. */
+	osmo_fsm_inst_term(rab_ass->fi, OSMO_FSM_TERM_REGULAR, NULL);
+}
+
+/* Add a single RAB from a RANAP/RUA RAB Assignment Response's list of RABs */
+static int ps_rab_setup_access_remote(struct ps_rab_ass *rab_ass,
+				      RANAP_RAB_SetupOrModifiedItem_t *rab_item)
+{
+	struct hnbgw_context_map *map = rab_ass->map;
+	uint8_t rab_id;
+	int rc;
+	struct ps_rab_rx_args args = {};
+
+	rab_id = rab_item->rAB_ID.buf[0];
+
+	rc = ranap_transp_layer_addr_decode2(&args.f_teid.addr, &args.use_x213_nsap, rab_item->transportLayerAddress);
+	if (rc < 0)
+		return rc;
+
+	/* Decode the GTP remote TEID */
+	if (!rab_item->iuTransportAssociation
+	    || rab_item->iuTransportAssociation->present != RANAP_IuTransportAssociation_PR_gTP_TEI)
+		return -1;
+	args.f_teid.teid = osmo_load32be(rab_item->iuTransportAssociation->choice.gTP_TEI.buf);
+	args.f_teid.present = true;
+
+	args.notify_fi = rab_ass->fi;
+
+	return ps_rab_rx_access_remote_f_teid(map, rab_id, &args);
+}
+
+int hnbgw_gtpmap_rx_rab_ass_resp(struct hnbgw_context_map *map, struct msgb *ranap_msg, ranap_message *message)
+{
+	/* hNodeB responds with its own F-TEIDs. Need to tell the UPF about those to complete the GTP mapping.
+	 * 1. here, extract the F-TEIDs (one per RAB),
+	 *    trigger each ps_rab_fsm to do a PFCP Session Modification.
+	 * 2. after all ps_rab_fsms responded with success, insert our Core side local F-TEIDs and send on the RAB
+	 *    Assignment Response to IuPS. (We already know the local F-TEIDs assigned by the UPF and could send on the
+	 *    RAB Assignment Response immediately, but rather wait for the PFCP mod req to succeed first.)
+	 *
+	 * To wait for all the RABs in this response message to complete, create a *separate* rab_ass_fsm instance from
+	 * the one created for the earlier RAB Assignment Request message. The reason is that technically we cannot
+	 * assume that the request and the response have exactly matching RAB IDs contained in them.
+	 *
+	 * In the vast majority of practical cases, there will be only one RAB Assignment Request message pending, but
+	 * for interop, by treating each RAB on its own and by treating request and response message separately from
+	 * each other, we are able to handle mismatching RAB IDs in request and response messages.
+	 */
+
+	RANAP_RAB_AssignmentResponseIEs_t *ies = &message->msg.raB_AssignmentResponseIEs;
+	int rc;
+	int i;
+	struct ps_rab_ass *rab_ass;
+
+	rab_ass = ps_rab_ass_alloc(map);
+	talloc_steal(rab_ass, message);
+	rab_ass->ranap_rab_ass_resp_message = message;
+	talloc_steal(rab_ass, ranap_msg);
+	rab_ass->ranap_rab_ass_resp_msgb = ranap_msg;
+	/* Now rab_ass owns message and will clean it up */
+
+	if (!osmo_pfcp_cp_peer_is_associated(g_hnbgw->pfcp.cp_peer)) {
+		LOG_PS_RAB_ASS(rab_ass, LOGL_ERROR, "PFCP is not associated, cannot set up GTP mapping\n");
+		goto no_rab;
+	}
+
+	/* setup-or-modify list */
+	if (ies->presenceMask & RAB_ASSIGNMENTRESPONSEIES_RANAP_RAB_SETUPORMODIFIEDLIST_PRESENT) {
+
+		LOG_PS_RAB_ASS(rab_ass, LOGL_INFO, "PS RAB-AssignmentResponse received, updating RABs\n");
+
+		/* Multiple RABs may be set up, bump matching FSMs in list map->ps_rab_list. */
+		for (i = 0; i < ies->raB_SetupOrModifiedList.raB_SetupOrModifiedList_ies.list.count; i++) {
+			RANAP_IE_t *list_ie;
+			RANAP_RAB_SetupOrModifiedItemIEs_t item_ies;
+
+			list_ie = ies->raB_SetupOrModifiedList.raB_SetupOrModifiedList_ies.list.array[i];
+			if (!list_ie)
+				continue;
+
+			rc = ranap_decode_rab_setupormodifieditemies_fromlist(&item_ies,
+									      &list_ie->value);
+			if (rc < 0) {
+				LOG_PS_RAB_ASS(rab_ass, LOGL_ERROR, "Failed to decode PS RAB-AssignmentResponse"
+					       " SetupOrModifiedItemIEs with list index %d\n", i);
+				goto continue_cleanloop;
+			}
+
+			if (ps_rab_setup_access_remote(rab_ass, &item_ies.raB_SetupOrModifiedItem))
+				LOG_PS_RAB_ASS(rab_ass, LOGL_ERROR, "Failed to apply PS RAB-AssignmentResponse"
+					       " SetupOrModifiedItemIEs with list index %d\n", i);
+			rab_ass->rabs_count++;
+
+continue_cleanloop:
+			ASN_STRUCT_FREE_CONTENTS_ONLY(asn_DEF_RANAP_RAB_SetupOrModifiedItem, &item_ies);
+		}
+	}
+
+	/* release list */
+	if (ies->presenceMask & RAB_ASSIGNMENTRESPONSEIES_RANAP_RAB_RELEASEDLIST_PRESENT) {
+		/* Multiple RABs may be set up, assemble in list map->ps_rab_list. */
+		RANAP_RAB_ReleasedList_t *r_list = &ies->raB_ReleasedList;
+		for (i = 0; i < r_list->raB_ReleasedList_ies.list.count; i++) {
+			RANAP_IE_t *released_list_ie = r_list->raB_ReleasedList_ies.list.array[i];
+			RANAP_RAB_ReleasedItemIEs_t _rab_rel_item_ies = {};
+			RANAP_RAB_ReleasedItemIEs_t *rab_rel_item_ies = &_rab_rel_item_ies;
+			RANAP_RAB_ReleasedItem_t *rab_rel_item;
+			uint8_t rab_id;
+			struct ps_rab *rab;
+
+			if (!released_list_ie)
+				goto no_rab;
+			if (released_list_ie->id != RANAP_ProtocolIE_ID_id_RAB_ReleasedItem)
+				goto no_rab;
+
+			rc = ranap_decode_rab_releaseditemies_fromlist(rab_rel_item_ies, &released_list_ie->value);
+			if (rc < 0) {
+				LOG_MAP(map, DLPFCP, LOGL_NOTICE, "Rx RAB ASS REQ (REL): Failed decoding ReleaseItem %u\n", i);
+				goto no_rab;
+			}
+
+			rab_rel_item = &rab_rel_item_ies->raB_ReleasedItem;
+			/* The RAB-ID is defined as a bitstring with a size of 8 (1 byte),
+			 * See also RANAP-IEs.asn, RAB-ID ::= BIT STRING (SIZE (8)) */
+			rab_id = rab_rel_item->rAB_ID.buf[0];
+			ASN_STRUCT_FREE_CONTENTS_ONLY(asn_DEF_RANAP_RAB_ReleasedItem, rab_rel_item_ies);
+
+			rab = ps_rab_get(map, rab_id);
+			if (rab) {
+				rab_ass->rabs_rel_count++;
+				ps_rab_release(rab, rab_ass->fi);
+			} else {
+				LOG_MAP(map, DLPFCP, LOGL_NOTICE, "Rx RAB ASS REQ (REL) for unknown rab_id %u\n", rab_id);
+			}
+		}
+	}
+
+	if (rab_ass->rabs_count > 0 || rab_ass->rabs_rel_count > 0) {
+		/* Got all RABs' state and updated their Access side GTP info in map->ps_rab_list.
+		 * For each RAB ID, the matching ps_rab_fsm has been instructed to tell the UPF about
+		 * the Access Remote GTP F-TEID. Each will call back with PS_RAB_ASS_EV_RAB_ESTABLISHED
+		 * or PS_RAB_ASS_EV_RAB_FAIL. */
+		return ps_rab_ass_fsm_state_chg(rab_ass->fi, PS_RAB_ASS_ST_WAIT_RABS_ESTABLISHED);
+	}
+
+	/* No Setup-or-modify nor Release RABs. Forward the message as is. */
+	rc = map_sccp_dispatch(map, MAP_SCCP_EV_TX_DATA_REQUEST, ranap_msg);
+	if (rc < 0) {
+		LOG_PS_RAB_ASS(rab_ass, LOGL_ERROR, "Sending RANAP PS RAB-AssignmentResponse failed\n");
+		goto no_rab;
+	}
+	/* The request message has been forwarded. We are done. */
+	osmo_fsm_inst_term(rab_ass->fi, OSMO_FSM_TERM_REGULAR, NULL);
+	return 0;
+
+no_rab:
+	ps_rab_ass_failure(rab_ass);
+	return -1;
+}
+
+static void ps_rab_ass_resp_send_if_ready(struct ps_rab_ass *rab_ass);
+static void ps_rab_ass_resp_send_if_ready_quick(struct ps_rab_ass *rab_ass)
+{
+	/* some RABs are still pending, postpone going through the message until all are done. */
+	if (rab_ass->rabs_done_count < rab_ass->rabs_count)
+		return;
+	if (rab_ass->rabs_rel_done_count < rab_ass->rabs_rel_count)
+		return;
+	ps_rab_ass_resp_send_if_ready(rab_ass);
+}
+
+static void ps_rab_ass_fsm_wait_rabs_established(struct osmo_fsm_inst *fi, uint32_t event, void *data)
+{
+	struct ps_rab_ass *rab_ass = fi->priv;
+
+	switch (event) {
+	case PS_RAB_ASS_EV_RAB_ESTABLISHED:
+		rab_ass->rabs_done_count++;
+		/* All RABs have succeeded, ready to forward */
+		ps_rab_ass_resp_send_if_ready_quick(rab_ass);
+		return;
+
+	case PS_RAB_ASS_EV_RAB_RELEASED:
+		rab_ass->rabs_rel_done_count++;
+		ps_rab_ass_resp_send_if_ready_quick(rab_ass);
+		return;
+
+	case PS_RAB_ASS_EV_RAB_FAIL:
+		ps_rab_ass_failure(rab_ass);
+		return;
+	default:
+		OSMO_ASSERT(false);
+	}
+}
+
+/* See whether all RABs are done establishing, and replace GTP info in the RAB Assignment Response message, so that we
+ * can forward the modified RAB Assignment Request to M3UA. */
+static void ps_rab_ass_resp_send_if_ready(struct ps_rab_ass *rab_ass)
+{
+	int i;
+	int rc;
+	RANAP_RAB_AssignmentResponseIEs_t *ies = &rab_ass->ranap_rab_ass_resp_message->msg.raB_AssignmentResponseIEs;
+	struct msgb *msg;
+
+	/* Go through all RABs in the RAB Assignment Response message and replace with the F-TEID that the UPF assigned,
+	 * verifying that instructing the UPF has succeeded. */
+	for (i = 0; i < ies->raB_SetupOrModifiedList.raB_SetupOrModifiedList_ies.list.count; i++) {
+		RANAP_IE_t *list_ie;
+		RANAP_RAB_SetupOrModifiedItemIEs_t item_ies;
+		RANAP_RAB_SetupOrModifiedItem_t *rab_item;
+		int rc;
+		uint8_t rab_id;
+		uint32_t teid_be;
+		struct ps_rab *rab;
+
+		list_ie = ies->raB_SetupOrModifiedList.raB_SetupOrModifiedList_ies.list.array[i];
+		if (!list_ie)
+			continue;
+
+		rc = ranap_decode_rab_setupormodifieditemies_fromlist(&item_ies,
+								      &list_ie->value);
+		if (rc < 0) {
+			LOG_PS_RAB_ASS(rab_ass, LOGL_ERROR, "Failed to decode PS RAB-AssignmentResponse"
+				       " SetupOrModifiedItemIEs with list index %d\n", i);
+			goto continue_cleanloop;
+		}
+
+		rab_item = &item_ies.raB_SetupOrModifiedItem;
+		rab_id = rab_item->rAB_ID.buf[0];
+
+		/* Find struct ps_rab for this rab_id */
+		rab = ps_rab_get(rab_ass->map, rab_id);
+		if (!ps_rab_is_established(rab)) {
+			/* Not ready to send on the RAB Assignment Response to M3UA, still waiting for it to be
+			 * established */
+			ASN_STRUCT_FREE_CONTENTS_ONLY(asn_DEF_RANAP_RAB_SetupOrModifiedItem, &item_ies);
+			return;
+		}
+
+		/* Replace GTP endpoint.
+		 * memory: ranap_new_transp_layer_addr() frees previous buffer in transportLayerAddress, if any. The
+		 * entire rab_item is freed along with item_ies.
+		 *
+		 * BTW, If I free this explicitly below with
+		 *   ASN_STRUCT_FREE_CONTENTS_ONLY(asn_DEF_BIT_STRING, &rab_item->transportLayerAddress);
+		 * that causes a leak in talloc_asn1_ctx: "iu_helpers.c:205 contains  20 bytes in  1 blocks".
+		 * I couldn't figure out why, but things are freed properly when leaving it all up to item_ies.
+		 */
+		if (ranap_new_transp_layer_addr(rab_item->transportLayerAddress, &rab->core.local.addr,
+						rab->access.use_x213_nsap) < 0) {
+			ASN_STRUCT_FREE_CONTENTS_ONLY(asn_DEF_RANAP_RAB_SetupOrModifiedItem, &item_ies);
+			LOG_PS_RAB_ASS(rab_ass, LOGL_ERROR, "Re-encoding RANAP PS RAB-AssignmentResponse failed\n");
+			ps_rab_ass_failure(rab_ass);
+			return;
+		}
+
+		LOG_PS_RAB_ASS(rab_ass, LOGL_DEBUG, "Re-encoding RANAP PS RAB-AssignmentResponse: RAB %u:"
+			       " RUA sent F-TEID %s-0x%x; replacing with %s-0x%x\n",
+			       rab_id,
+			       osmo_sockaddr_to_str_c(OTC_SELECT, &rab->access.remote.addr), rab->access.remote.teid,
+			       osmo_sockaddr_to_str_c(OTC_SELECT, &rab->core.local.addr), rab->core.local.teid);
+
+		teid_be = htonl(rab->core.local.teid);
+		rab_item->iuTransportAssociation->present = RANAP_IuTransportAssociation_PR_gTP_TEI;
+		/* memory: OCTET_STRING_fromBuf() frees previous buffer in gTP_TEI, if any. The entire rab_item is freed
+		 * along with item_ies. */
+		OCTET_STRING_fromBuf(&rab_item->iuTransportAssociation->choice.gTP_TEI,
+				     (const char *)&teid_be, sizeof(teid_be));
+
+		/* Reencode this list item in the RANAP message */
+		rc = ANY_fromType_aper(&list_ie->value, &asn_DEF_RANAP_RAB_SetupOrModifiedItem, rab_item);
+		if (rc < 0) {
+			ASN_STRUCT_FREE_CONTENTS_ONLY(asn_DEF_RANAP_RAB_SetupOrModifiedItem, &item_ies);
+			LOG_PS_RAB_ASS(rab_ass, LOGL_ERROR, "Re-encoding RANAP PS RAB-AssignmentResponse failed\n");
+			ps_rab_ass_failure(rab_ass);
+			return;
+		}
+
+continue_cleanloop:
+		ASN_STRUCT_FREE_CONTENTS_ONLY(asn_DEF_RANAP_RAB_SetupOrModifiedItem, &item_ies);
+	}
+
+	msg = rab_ass->ranap_rab_ass_resp_msgb;
+	rab_ass->ranap_rab_ass_resp_msgb = NULL;
+	talloc_steal(OTC_SELECT, msg);
+
+	/* Replaced all the GTP info, re-encode the message. Since we are replacing data 1:1, taking care to use the
+	 * same IP address encoding, the resulting message size must be identical to the original message size. */
+	rc = ranap_rab_ass_resp_encode(msgb_l2(msg), msgb_l2len(msg), ies);
+	if (rc < 0) {
+		LOG_PS_RAB_ASS(rab_ass, LOGL_ERROR, "Re-encoding RANAP PS RAB-AssignmentResponse failed\n");
+		ps_rab_ass_failure(rab_ass);
+		return;
+	}
+
+	LOG_PS_RAB_ASS(rab_ass, LOGL_INFO, "Sending RANAP PS RAB-AssignmentResponse with mapped GTP info\n");
+
+	rc = map_sccp_dispatch(rab_ass->map, MAP_SCCP_EV_TX_DATA_REQUEST, msg);
+	if (rc < 0) {
+		LOG_PS_RAB_ASS(rab_ass, LOGL_ERROR, "Sending RANAP PS RAB-AssignmentResponse failed\n");
+		ps_rab_ass_failure(rab_ass);
+		return;
+	}
+	/* The request message has been forwarded. We are done. */
+	osmo_fsm_inst_term(rab_ass->fi, OSMO_FSM_TERM_REGULAR, NULL);
+}
+
+static void ps_rab_ass_fsm_cleanup(struct osmo_fsm_inst *fi, enum osmo_fsm_term_cause cause)
+{
+	struct ps_rab_ass *rab_ass = fi->priv;
+	struct ps_rab *rab;
+
+	llist_for_each_entry(rab, &rab_ass->map->ps_rab_list, entry) {
+		if (rab->req_fi == fi)
+			rab->req_fi = NULL;
+		if (rab->resp_fi == fi)
+			rab->resp_fi = NULL;
+	}
+
+	/* remove from map->ps_rab_ass_list */
+	llist_del(&rab_ass->entry);
+}
+
+void hnbgw_gtpmap_release(struct hnbgw_context_map *map)
+{
+	struct ps_rab_ass *rab_ass, *next;
+	struct ps_rab *rab, *next2;
+	llist_for_each_entry_safe(rab, next2, &map->ps_rab_list, entry) {
+		ps_rab_release(rab, NULL);
+	}
+	llist_for_each_entry_safe(rab_ass, next, &map->ps_rab_ass_list, entry) {
+		osmo_fsm_inst_term(rab_ass->fi, OSMO_FSM_TERM_REGULAR, NULL);
+	}
+}
+
+#define S(x) (1 << (x))
+
+static const struct osmo_fsm_state ps_rab_ass_fsm_states[] = {
+	[PS_RAB_ASS_ST_RX_RAB_ASS_MSG] = {
+		.name = "RX_RAB_ASS_MSG",
+		.out_state_mask = 0
+			| S(PS_RAB_ASS_ST_WAIT_LOCAL_F_TEIDS)
+			| S(PS_RAB_ASS_ST_WAIT_RABS_ESTABLISHED)
+			,
+	},
+	[PS_RAB_ASS_ST_WAIT_LOCAL_F_TEIDS] = {
+		.name = "WAIT_LOCAL_F_TEIDS",
+		.action = ps_rab_ass_fsm_wait_local_f_teids,
+		.in_event_mask = 0
+			| S(PS_RAB_ASS_EV_LOCAL_F_TEIDS_RX)
+			| S(PS_RAB_ASS_EV_RAB_FAIL)
+			,
+	},
+	[PS_RAB_ASS_ST_WAIT_RABS_ESTABLISHED] = {
+		.name = "WAIT_RABS_ESTABLISHED",
+		.action = ps_rab_ass_fsm_wait_rabs_established,
+		.in_event_mask = 0
+			| S(PS_RAB_ASS_EV_RAB_ESTABLISHED)
+			| S(PS_RAB_ASS_EV_RAB_RELEASED)
+			| S(PS_RAB_ASS_EV_RAB_FAIL)
+			,
+	},
+};
+
+int ps_rab_ass_fsm_timer_cb(struct osmo_fsm_inst *fi)
+{
+	struct ps_rab_ass *rab_ass = fi->priv;
+	LOG_PS_RAB_ASS(rab_ass, LOGL_ERROR, "Timeout of " OSMO_T_FMT "\n", OSMO_T_FMT_ARGS(fi->T));
+	/* terminate */
+	return 1;
+}
+
+static struct osmo_fsm ps_rab_ass_fsm = {
+	.name = "ps_rab_ass",
+	.states = ps_rab_ass_fsm_states,
+	.num_states = ARRAY_SIZE(ps_rab_ass_fsm_states),
+	.log_subsys = DRANAP,
+	.event_names = ps_rab_ass_fsm_event_names,
+	.cleanup = ps_rab_ass_fsm_cleanup,
+	.timer_cb = ps_rab_ass_fsm_timer_cb,
+};
+
+static __attribute__((constructor)) void ps_rab_ass_fsm_register(void)
+{
+	OSMO_ASSERT(osmo_fsm_register(&ps_rab_ass_fsm) == 0);
+}

src/osmo-hnbgw/ps_rab_fsm.c

@@ -0,0 +1,833 @@
+/* Handle PFCP communication with the UPF for a single RAB. */
+/* (C) 2022 by sysmocom s.f.m.c. GmbH <info@sysmocom.de>
+ * All Rights Reserved
+ *
+ * Author: Neels Janosch Hofmeyr <nhofmeyr@sysmocom.de>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ */
+
+#include <errno.h>
+
+#include <osmocom/core/tdef.h>
+
+#include <osmocom/pfcp/pfcp_endpoint.h>
+#include <osmocom/pfcp/pfcp_cp_peer.h>
+
+#include <osmocom/hnbgw/hnbgw.h>
+#include <osmocom/hnbgw/context_map.h>
+#include <osmocom/hnbgw/tdefs.h>
+#include <osmocom/hnbgw/ps_rab_fsm.h>
+#include <osmocom/hnbgw/ps_rab_ass_fsm.h>
+
+#define LOG_PS_RAB(RAB, LOGL, FMT, ARGS...) \
+	LOGPFSML((RAB) ? (RAB)->fi : NULL, LOGL, FMT, ##ARGS)
+
+enum ps_rab_state {
+	PS_RAB_ST_RX_CORE_REMOTE_F_TEID,
+	PS_RAB_ST_WAIT_PFCP_EST_RESP,
+	PS_RAB_ST_WAIT_ACCESS_REMOTE_F_TEID,
+	PS_RAB_ST_WAIT_PFCP_MOD_RESP,
+	PS_RAB_ST_ESTABLISHED,
+	PS_RAB_ST_WAIT_PFCP_DEL_RESP,
+	PS_RAB_ST_WAIT_USE_COUNT,
+};
+
+enum ps_rab_event {
+	PS_RAB_EV_PFCP_EST_RESP,
+	PS_RAB_EV_RX_ACCESS_REMOTE_F_TEID,
+	PS_RAB_EV_PFCP_MOD_RESP,
+	PS_RAB_EV_PFCP_DEL_RESP,
+	PS_RAB_EV_USE_COUNT_ZERO,
+};
+
+static const struct value_string ps_rab_fsm_event_names[] = {
+	OSMO_VALUE_STRING(PS_RAB_EV_PFCP_EST_RESP),
+	OSMO_VALUE_STRING(PS_RAB_EV_RX_ACCESS_REMOTE_F_TEID),
+	OSMO_VALUE_STRING(PS_RAB_EV_PFCP_MOD_RESP),
+	OSMO_VALUE_STRING(PS_RAB_EV_PFCP_DEL_RESP),
+	OSMO_VALUE_STRING(PS_RAB_EV_USE_COUNT_ZERO),
+	{}
+};
+
+struct osmo_tdef_state_timeout ps_rab_fsm_timeouts[32] = {
+	/* PS_RAB_ST_WAIT_PFCP_EST_RESP is terminated by PFCP timeouts via resp_cb() */
+	/* PS_RAB_ST_WAIT_ACCESS_REMOTE_F_TEID is terminated by ps_rab_ass_fsm */
+	/* PS_RAB_ST_WAIT_PFCP_MOD_RESP is terminated by PFCP timeouts via resp_cb() */
+	/* PS_RAB_ST_WAIT_PFCP_DEL_RESP is terminated by PFCP timeouts via resp_cb() */
+};
+
+enum pdr_far_id {
+	ID_CORE_TO_ACCESS = 1,
+	ID_ACCESS_TO_CORE = 2,
+};
+
+
+#define ps_rab_fsm_state_chg(state) \
+	osmo_tdef_fsm_inst_state_chg(fi, state, ps_rab_fsm_timeouts, hnbgw_T_defs, -1)
+
+#define PS_RAB_USE_ACTIVE "active"
+
+static struct osmo_fsm ps_rab_fsm;
+
+static int ps_rab_fsm_use_cb(struct osmo_use_count_entry *e, int32_t old_use_count, const char *file, int line);
+
+static struct ps_rab *ps_rab_alloc(struct hnbgw_context_map *map, uint8_t rab_id)
+{
+	struct osmo_fsm_inst *fi;
+	struct ps_rab *rab;
+
+	/* Allocate with the global hnb_gw, so that we can gracefully handle PFCP release even if a hnb_ctx gets
+	 * deallocated. */
+	fi = osmo_fsm_inst_alloc(&ps_rab_fsm, g_hnbgw, NULL, LOGL_DEBUG, NULL);
+	OSMO_ASSERT(fi);
+	osmo_fsm_inst_update_id_f_sanitize(fi, '-', "%s-RUA-%u-RAB-%u", hnb_context_name(map->hnb_ctx), map->rua_ctx_id,
+					   rab_id);
+
+	rab = talloc(fi, struct ps_rab);
+	OSMO_ASSERT(rab);
+	*rab = (struct ps_rab){
+		.fi = fi,
+		.map = map,
+		.rab_id = rab_id,
+		.use_count = {
+			.talloc_object = rab,
+			.use_cb = ps_rab_fsm_use_cb,
+		},
+	};
+	fi->priv = rab;
+
+	OSMO_ASSERT(osmo_use_count_get_put(&rab->use_count, PS_RAB_USE_ACTIVE, 1) == 0);
+
+	llist_add_tail(&rab->entry, &map->ps_rab_list);
+	return rab;
+}
+
+/* Iterate all ps_rab instances of all context maps and return the one matching the given SEID.
+ * If is_cp_seid == true, match seid with rab->cp_seid (e.g. for received PFCP messages).
+ * Otherwise match seid with rab->up_f_seid.seid (e.g. for sent PFCP messages). */
+struct ps_rab *ps_rab_find_by_seid(uint64_t seid, bool is_cp_seid)
+{
+	struct hnb_context *hnb;
+	llist_for_each_entry(hnb, &g_hnbgw->hnb_list, list) {
+		struct hnbgw_context_map *map;
+		llist_for_each_entry(map, &hnb->map_list, hnb_list) {
+			struct ps_rab *rab;
+			llist_for_each_entry(rab, &map->ps_rab_list, entry) {
+				uint64_t rab_seid = is_cp_seid ? rab->cp_seid : rab->up_f_seid.seid;
+				if (rab_seid == seid)
+					return rab;
+			}
+		}
+	}
+	return NULL;
+}
+
+void ps_rab_pfcp_set_msg_ctx(struct ps_rab *rab, struct osmo_pfcp_msg *m)
+{
+	if (m->ctx.session_fi)
+		return;
+	m->ctx.session_fi = rab->fi;
+	m->ctx.session_use_count = &rab->use_count;
+	m->ctx.session_use_token = "PFCP_MSG";
+	OSMO_ASSERT(osmo_use_count_get_put(m->ctx.session_use_count, m->ctx.session_use_token, 1) == 0);
+}
+
+static struct osmo_pfcp_msg *ps_rab_new_pfcp_msg_req(struct ps_rab *rab, enum osmo_pfcp_message_type msg_type)
+{
+	struct osmo_pfcp_msg *m = osmo_pfcp_cp_peer_new_req(g_hnbgw->pfcp.cp_peer, msg_type);
+
+	m->h.seid_present = true;
+	m->h.seid = rab->up_f_seid.seid;
+	ps_rab_pfcp_set_msg_ctx(rab, m);
+	return m;
+}
+
+struct ps_rab *ps_rab_get(struct hnbgw_context_map *map, uint8_t rab_id)
+{
+	struct ps_rab *rab;
+	llist_for_each_entry(rab, &map->ps_rab_list, entry) {
+		if (rab->rab_id != rab_id)
+			continue;
+		return rab;
+	}
+	return NULL;
+}
+
+bool ps_rab_is_established(const struct ps_rab *rab)
+{
+	return rab && rab->fi->state == PS_RAB_ST_ESTABLISHED;
+}
+
+void ps_rab_failure(struct ps_rab *rab)
+{
+	if (rab->req_fi)
+		osmo_fsm_inst_dispatch(rab->req_fi, PS_RAB_ASS_EV_RAB_FAIL, rab);
+	if (rab->resp_fi)
+		osmo_fsm_inst_dispatch(rab->resp_fi, PS_RAB_ASS_EV_RAB_FAIL, rab);
+	ps_rab_release(rab, NULL);
+}
+
+struct ps_rab *ps_rab_start(struct hnbgw_context_map *map, uint8_t rab_id,
+			    const struct addr_teid *core_f_teid, bool use_x213_nsap,
+			    struct osmo_fsm_inst *req_fi)
+{
+	struct osmo_fsm_inst *fi;
+	struct ps_rab *rab;
+
+	rab = ps_rab_alloc(map, rab_id);
+	fi = rab->fi;
+	rab->req_fi = req_fi;
+	rab->core.remote = *core_f_teid;
+	rab->core.use_x213_nsap = use_x213_nsap;
+
+	/* Got the RAB's Core side GTP info. Route the GTP for via the local UPF.
+	 * Establish a PFCP session with the UPF: tell it about the Core side GTP endpoint and request local F-TEIDs. */
+	if (ps_rab_fsm_state_chg(PS_RAB_ST_WAIT_PFCP_EST_RESP)) {
+		osmo_fsm_inst_term(fi, OSMO_FSM_TERM_REGULAR, NULL);
+		return NULL;
+	}
+
+	return rab;
+}
+
+#define set_netinst(NETINST_MEMBER, STRING) do { \
+		if ((STRING) && *(STRING)) { \
+			NETINST_MEMBER##_present = true; \
+			OSMO_STRLCPY_ARRAY(NETINST_MEMBER.str, STRING); \
+		} \
+	} while (0)
+
+/* Add two PDR and two FAR to the PFCP Session Establishment Request message, according to the information found in rab.
+ */
+static int rab_to_pfcp_session_est_req(struct osmo_pfcp_msg_session_est_req *ser, struct ps_rab *rab)
+{
+	if (ser->create_pdr_count + 2 > ARRAY_SIZE(ser->create_pdr)
+	    || ser->create_far_count + 2 > ARRAY_SIZE(ser->create_far)) {
+		LOG_PS_RAB(rab, LOGL_ERROR, "insufficient space for Create PDR / Create FAR IEs\n");
+		return -1;
+	}
+
+	/* Core to Access:
+	 * - UPF should return an F-TEID for the PDR, to be forwarded back to Core later in
+	 *   RANAP RAB Assignment Response.
+	 * - we don't know the Access side GTP address yet, so set FAR to DROP.
+	 */
+	ser->create_pdr[ser->create_pdr_count] = (struct osmo_pfcp_ie_create_pdr){
+		.pdr_id = ID_CORE_TO_ACCESS,
+		.precedence = 255,
+		.pdi = {
+			.source_iface = OSMO_PFCP_SOURCE_IFACE_CORE,
+			.local_f_teid_present = true,
+			.local_f_teid = {
+				.choose_flag = true,
+				.choose = {
+					.ipv4_addr = true,
+				},
+			},
+		},
+		.outer_header_removal_present = true,
+		.outer_header_removal = {
+			.desc = OSMO_PFCP_OUTER_HEADER_REMOVAL_GTP_U_UDP_IPV4,
+		},
+		.far_id_present = true,
+		.far_id = ID_CORE_TO_ACCESS,
+	};
+	set_netinst(ser->create_pdr[ser->create_pdr_count].pdi.network_inst, g_hnbgw->config.pfcp.netinst.core);
+	ser->create_pdr_count++;
+
+	ser->create_far[ser->create_far_count] = (struct osmo_pfcp_ie_create_far){
+		.far_id = ID_CORE_TO_ACCESS,
+	};
+	osmo_pfcp_bits_set(ser->create_far[ser->create_far_count].apply_action.bits,
+			   OSMO_PFCP_APPLY_ACTION_DROP, true);
+	ser->create_far_count++;
+
+	/* Access to Core:
+	 * - UPF should return an F-TEID for the PDR, to be forwarded to Access in the modified
+	 *   RANAP RAB Assignment Request.
+	 * - we already know the Core's GTP endpoint F-TEID, so fully set up this FAR.
+	 */
+	ser->create_pdr[ser->create_pdr_count] = (struct osmo_pfcp_ie_create_pdr){
+		.pdr_id = ID_ACCESS_TO_CORE,
+		.precedence = 255,
+		.pdi = {
+			.source_iface = OSMO_PFCP_SOURCE_IFACE_ACCESS,
+			.local_f_teid_present = true,
+			.local_f_teid = {
+				.choose_flag = true,
+				.choose = {
+					.ipv4_addr = true,
+				},
+			},
+		},
+		.outer_header_removal_present = true,
+		.outer_header_removal = {
+			.desc = OSMO_PFCP_OUTER_HEADER_REMOVAL_GTP_U_UDP_IPV4,
+		},
+		.far_id_present = true,
+		.far_id = ID_ACCESS_TO_CORE,
+	};
+	set_netinst(ser->create_pdr[ser->create_pdr_count].pdi.network_inst, g_hnbgw->config.pfcp.netinst.access);
+	ser->create_pdr_count++;
+
+	ser->create_far[ser->create_far_count] = (struct osmo_pfcp_ie_create_far){
+		.far_id = ID_ACCESS_TO_CORE,
+		.forw_params_present = true,
+		.forw_params = {
+			.destination_iface = OSMO_PFCP_DEST_IFACE_CORE,
+			.outer_header_creation_present = true,
+			.outer_header_creation = {
+				.teid_present = true,
+				.teid = rab->core.remote.teid,
+				.ip_addr.v4_present = true,
+				.ip_addr.v4 = rab->core.remote.addr,
+			},
+		},
+	};
+	osmo_pfcp_bits_set(ser->create_far[ser->create_far_count].forw_params.outer_header_creation.desc_bits,
+			   OSMO_PFCP_OUTER_HEADER_CREATION_GTP_U_UDP_IPV4, true);
+	osmo_pfcp_bits_set(ser->create_far[ser->create_far_count].apply_action.bits,
+			   OSMO_PFCP_APPLY_ACTION_FORW, true);
+	set_netinst(ser->create_far[ser->create_far_count].forw_params.network_inst, g_hnbgw->config.pfcp.netinst.core);
+	ser->create_far_count++;
+
+	return 0;
+}
+
+static int on_pfcp_est_resp(struct osmo_pfcp_msg *req, struct osmo_pfcp_msg *rx_resp, const char *errmsg);
+
+static void ps_rab_fsm_wait_pfcp_est_resp_onenter(struct osmo_fsm_inst *fi, uint32_t prev_state)
+{
+	struct ps_rab *rab = fi->priv;
+	struct osmo_pfcp_msg *m;
+	struct osmo_pfcp_ie_f_seid cp_f_seid;
+	struct osmo_pfcp_msg_session_est_req *ser;
+
+	/* So far we have the rab->core.remote information. Send that to the UPF.
+	 * Also request all local GTP endpoints from UPF (rab->{core,access}.local) */
+	m = ps_rab_new_pfcp_msg_req(rab, OSMO_PFCP_MSGT_SESSION_EST_REQ);
+
+	/* Send UP-SEID as zero, the UPF has yet to assign a SEID for itself remotely */
+	m->h.seid = 0;
+
+	/* Make a new CP-SEID, our local reference for the PFCP session. */
+	rab->cp_seid = osmo_pfcp_cp_peer_next_seid(g_hnbgw->pfcp.cp_peer);
+	cp_f_seid = (struct osmo_pfcp_ie_f_seid){
+		.seid = rab->cp_seid,
+	};
+	osmo_pfcp_ip_addrs_set(&cp_f_seid.ip_addr, &osmo_pfcp_endpoint_get_cfg(g_hnbgw->pfcp.ep)->local_addr);
+
+	m->ies.session_est_req = (struct osmo_pfcp_msg_session_est_req){
+		.node_id = m->ies.session_est_req.node_id,
+		.cp_f_seid_present = true,
+		.cp_f_seid = cp_f_seid,
+	};
+	ser = &m->ies.session_est_req;
+
+	/* Create PDR+FAR pairs */
+	if (rab_to_pfcp_session_est_req(ser, rab)) {
+		LOG_PS_RAB(rab, LOGL_ERROR, "Failed to compose PFCP message\n");
+		osmo_pfcp_msg_free(m);
+		ps_rab_failure(rab);
+		return;
+	}
+
+	/* Send PFCP Session Establishment Request to UPF, wait for response. */
+	m->ctx.resp_cb = on_pfcp_est_resp;
+	if (osmo_pfcp_endpoint_tx(g_hnbgw->pfcp.ep, m)) {
+		LOG_PS_RAB(rab, LOGL_ERROR, "Failed to send PFCP message\n");
+		ps_rab_failure(rab);
+	}
+}
+
+static int on_pfcp_est_resp(struct osmo_pfcp_msg *req, struct osmo_pfcp_msg *rx_resp, const char *errmsg)
+{
+	struct ps_rab *rab = req->ctx.session_fi->priv;
+
+	/* Send as FSM event to ensure this step is currently allowed */
+	osmo_fsm_inst_dispatch(rab->fi, PS_RAB_EV_PFCP_EST_RESP, rx_resp);
+
+	/* By returning 0 here, the rx_resp message is not dispatched "again" to pfcp_ep->rx_msg(). We've handled it
+	 * here already. */
+	return 0;
+}
+
+static void ps_rab_rx_pfcp_est_resp(struct osmo_fsm_inst *fi, struct osmo_pfcp_msg *rx);
+
+static void ps_rab_fsm_wait_pfcp_est_resp(struct osmo_fsm_inst *fi, uint32_t event, void *data)
+{
+	switch (event) {
+	case PS_RAB_EV_PFCP_EST_RESP:
+		ps_rab_rx_pfcp_est_resp(fi, data);
+		break;
+
+	default:
+		OSMO_ASSERT(false);
+	}
+}
+
+/* Look for dst->local.pdr_id in ser->created_pdr[], and copy the GTP endpoint info to dst->local.addr_teid, if found. */
+static int get_local_f_teid_from_created_pdr(struct half_gtp_map *dst, struct osmo_pfcp_msg_session_est_resp *ser,
+					     uint8_t pdr_id)
+{
+	int i;
+	for (i = 0; i < ser->created_pdr_count; i++) {
+		struct osmo_pfcp_ie_created_pdr *cpdr = &ser->created_pdr[i];
+		if (cpdr->pdr_id != pdr_id)
+			continue;
+		if (!cpdr->local_f_teid_present)
+			continue;
+		if (cpdr->local_f_teid.choose_flag)
+			continue;
+		if (!cpdr->local_f_teid.fixed.ip_addr.v4_present)
+			continue;
+		dst->local.addr = cpdr->local_f_teid.fixed.ip_addr.v4;
+		dst->local.teid = cpdr->local_f_teid.fixed.teid;
+		dst->local.present = true;
+		return 0;
+	}
+	return -1;
+}
+
+static void ps_rab_rx_pfcp_est_resp(struct osmo_fsm_inst *fi, struct osmo_pfcp_msg *rx)
+{
+	struct ps_rab *rab = fi->priv;
+	enum osmo_pfcp_cause *cause;
+	struct osmo_pfcp_msg_session_est_resp *ser;
+
+	if (!rx) {
+		/* This happens when no response has arrived after all PFCP timeouts and retransmissions. */
+		LOG_PS_RAB(rab, LOGL_ERROR, "No response to PFCP Session Establishment Request\n");
+		goto pfcp_session_est_failed;
+	}
+
+	ser = &rx->ies.session_est_resp;
+
+	cause = osmo_pfcp_msg_cause(rx);
+	if (!cause || *cause != OSMO_PFCP_CAUSE_REQUEST_ACCEPTED) {
+		LOG_PS_RAB(rab, LOGL_ERROR, "PFCP Session Establishment Response was not successful: %s\n",
+			   cause ? osmo_pfcp_cause_str(*cause) : "NULL");
+		goto pfcp_session_est_failed;
+	}
+
+	/* Get the UPF's SEID for future messages for this PFCP session */
+	if (!ser->up_f_seid_present) {
+		LOG_PS_RAB(rab, LOGL_ERROR, "PFCP Session Establishment Response lacks a UP F-SEID\n");
+		goto pfcp_session_est_failed;
+	}
+	rab->up_f_seid = ser->up_f_seid;
+
+	if (rab->release_requested) {
+		/* The UE conn or the entire HNB has released while we were waiting for a PFCP response. Now that there
+		 * is a remote SEID, we can finally delete the session that we asked for earlier. */
+		ps_rab_fsm_state_chg(PS_RAB_ST_WAIT_PFCP_DEL_RESP);
+		return;
+	}
+
+	/* Get the UPF's local F-TEIDs for both Core and Access */
+	if (get_local_f_teid_from_created_pdr(&rab->core, ser, ID_CORE_TO_ACCESS)
+	    || get_local_f_teid_from_created_pdr(&rab->access, ser, ID_ACCESS_TO_CORE)) {
+		LOG_PS_RAB(rab, LOGL_ERROR, "Missing F-TEID in PFCP Session Establishment Response\n");
+		ps_rab_failure(rab);
+		return;
+	}
+
+	if (rab->req_fi)
+		osmo_fsm_inst_dispatch(rab->req_fi, PS_RAB_ASS_EV_LOCAL_F_TEIDS_RX, rab);
+
+	/* The RAB Assignment Response will yield the hNodeB's F-TEID, i.e. the F-TEID we are supposed to send to Access
+	 * in outgoing GTP packets. */
+	ps_rab_fsm_state_chg(PS_RAB_ST_WAIT_ACCESS_REMOTE_F_TEID);
+	return;
+
+pfcp_session_est_failed:
+	if (rab->release_requested) {
+		/* the RAB was released and we were waiting for some PFCP responsewhile waiting for a response, and now
+		 * we know that no session has been created. No PFCP left, deallocate. */
+		ps_rab_fsm_state_chg(PS_RAB_ST_WAIT_USE_COUNT);
+		return;
+	}
+	ps_rab_failure(rab);
+}
+
+int ps_rab_rx_access_remote_f_teid(struct hnbgw_context_map *map, uint8_t rab_id,
+				   const struct ps_rab_rx_args *args)
+{
+	int rc;
+	struct ps_rab *rab = ps_rab_get(map, rab_id);
+	if (!rab) {
+		LOG_MAP(map, DLPFCP, LOGL_ERROR, "There is no RAB with id %u\n", rab_id);
+		return -ENOENT;
+	}
+	/* Dispatch as event to make sure this is currently allowed */
+	rc = osmo_fsm_inst_dispatch(rab->fi, PS_RAB_EV_RX_ACCESS_REMOTE_F_TEID, (void *)args);
+	if (rc)
+		return rc;
+	return 0;
+}
+
+static void ps_rab_fsm_wait_access_remote_f_teid(struct osmo_fsm_inst *fi, uint32_t event, void *data)
+{
+	struct ps_rab *rab = fi->priv;
+	const struct ps_rab_rx_args *args;
+	switch (event) {
+	case PS_RAB_EV_RX_ACCESS_REMOTE_F_TEID:
+		args = data;
+		rab->resp_fi = args->notify_fi;
+		rab->access.use_x213_nsap = args->use_x213_nsap;
+		rab->access.remote = args->f_teid;
+		ps_rab_fsm_state_chg(PS_RAB_ST_WAIT_PFCP_MOD_RESP);
+		return;
+	default:
+		OSMO_ASSERT(false);
+	}
+}
+
+/* Add an Update FAR to the PFCP Session Modification Request message, updating a remote F-TEID. */
+static int rab_to_pfcp_session_mod_req_upd_far(struct osmo_pfcp_msg_session_mod_req *smr,
+					       uint32_t far_id, const struct addr_teid *remote_f_teid,
+					       const char *far_netinst)
+{
+	if (smr->upd_far_count + 1 > ARRAY_SIZE(smr->upd_far))
+		return -1;
+
+	smr->upd_far[smr->upd_far_count] = (struct osmo_pfcp_ie_upd_far){
+		.far_id = far_id,
+		.apply_action_present = true,
+		/* apply_action.bits set below */
+		.upd_forw_params_present = true,
+		.upd_forw_params = {
+			.outer_header_creation_present = true,
+			.outer_header_creation = {
+				/* desc_bits set below */
+				.teid_present = true,
+				.teid = remote_f_teid->teid,
+				.ip_addr.v4_present = true,
+				.ip_addr.v4 = remote_f_teid->addr,
+			},
+		},
+	};
+	osmo_pfcp_bits_set(smr->upd_far[smr->upd_far_count].apply_action.bits,
+			   OSMO_PFCP_APPLY_ACTION_FORW, true);
+	osmo_pfcp_bits_set(smr->upd_far[smr->upd_far_count].upd_forw_params.outer_header_creation.desc_bits,
+			   OSMO_PFCP_OUTER_HEADER_CREATION_GTP_U_UDP_IPV4, true);
+	set_netinst(smr->upd_far[smr->upd_far_count].upd_forw_params.network_inst, far_netinst);
+	smr->upd_far_count++;
+
+	return 0;
+}
+
+static int on_pfcp_mod_resp(struct osmo_pfcp_msg *req, struct osmo_pfcp_msg *rx_resp, const char *errmsg);
+
+static void ps_rab_fsm_wait_pfcp_mod_resp_onenter(struct osmo_fsm_inst *fi, uint32_t prev_state)
+{
+	/* We have been given the Access side's remote F-TEID, now in rab->access.remote, and we need to tell the UPF
+	 * about it. This affects the Core to Access direction: now we know where to forward payloads coming from Core.
+	 */
+	struct ps_rab *rab = fi->priv;
+	struct osmo_pfcp_msg *m;
+
+	if (!(rab->up_f_seid.ip_addr.v4_present /* || rab->up_f_seid.ip_addr.v6_present */)) {
+		LOG_PS_RAB(rab, LOGL_ERROR, "no valid PFCP session\n");
+		ps_rab_failure(rab);
+		return;
+	}
+
+	m = ps_rab_new_pfcp_msg_req(rab, OSMO_PFCP_MSGT_SESSION_MOD_REQ);
+
+	if (rab_to_pfcp_session_mod_req_upd_far(&m->ies.session_mod_req, ID_CORE_TO_ACCESS, &rab->access.remote,
+						g_hnbgw->config.pfcp.netinst.access)) {
+		LOG_PS_RAB(rab, LOGL_ERROR, "error composing Update FAR IE in PFCP msg\n");
+		ps_rab_failure(rab);
+		return;
+	}
+
+	m->ctx.resp_cb = on_pfcp_mod_resp;
+	if (osmo_pfcp_endpoint_tx(g_hnbgw->pfcp.ep, m)) {
+		LOG_PS_RAB(rab, LOGL_ERROR, "Failed to send PFCP message\n");
+		ps_rab_failure(rab);
+	}
+}
+
+static int on_pfcp_mod_resp(struct osmo_pfcp_msg *req, struct osmo_pfcp_msg *rx_resp, const char *errmsg)
+{
+	struct ps_rab *rab = req->ctx.session_fi->priv;
+
+	/* Send as FSM event to ensure this step is currently allowed */
+	osmo_fsm_inst_dispatch(rab->fi, PS_RAB_EV_PFCP_MOD_RESP, rx_resp);
+
+	/* By returning 0 here, the rx_resp message is not dispatched "again" to pfcp_ep->rx_msg(). We've handled it
+	 * here already. */
+	return 0;
+}
+
+static void ps_rab_rx_pfcp_mod_resp(struct osmo_fsm_inst *fi, struct osmo_pfcp_msg *rx);
+
+static void ps_rab_fsm_wait_pfcp_mod_resp(struct osmo_fsm_inst *fi, uint32_t event, void *data)
+{
+	switch (event) {
+	case PS_RAB_EV_PFCP_MOD_RESP:
+		ps_rab_rx_pfcp_mod_resp(fi, data);
+		return;
+	default:
+		OSMO_ASSERT(false);
+	}
+}
+
+static void ps_rab_rx_pfcp_mod_resp(struct osmo_fsm_inst *fi, struct osmo_pfcp_msg *rx)
+{
+	struct ps_rab *rab = fi->priv;
+	enum osmo_pfcp_cause *cause;
+
+	if (!rx) {
+		LOG_PS_RAB(rab, LOGL_ERROR, "No response to PFCP Session Modification Request\n");
+		ps_rab_failure(rab);
+		return;
+	}
+
+	cause = osmo_pfcp_msg_cause(rx);
+	if (!cause || *cause != OSMO_PFCP_CAUSE_REQUEST_ACCEPTED) {
+		LOG_PS_RAB(rab, LOGL_ERROR, "PFCP Session Modification Response was not successful: %s\n",
+			   cause ? osmo_pfcp_cause_str(*cause) : "NULL");
+		ps_rab_failure(rab);
+		return;
+	}
+
+	/* This RAB is now complete. Everything went as expected, now we can forward the RAB Assignment Response to the
+	 * CN. */
+	ps_rab_fsm_state_chg(PS_RAB_ST_ESTABLISHED);
+}
+
+static void ps_rab_fsm_established_onenter(struct osmo_fsm_inst *fi, uint32_t prev_state)
+{
+	struct ps_rab *rab = fi->priv;
+	if (rab->resp_fi)
+		osmo_fsm_inst_dispatch(rab->resp_fi, PS_RAB_ASS_EV_RAB_ESTABLISHED, rab);
+}
+
+static int on_pfcp_del_resp(struct osmo_pfcp_msg *req, struct osmo_pfcp_msg *rx_resp, const char *errmsg);
+
+static void ps_rab_fsm_wait_pfcp_del_resp_onenter(struct osmo_fsm_inst *fi, uint32_t prev_state)
+{
+	/* If a PFCP session has been established, send a Session Deletion Request and wait for the response.
+	 * If no session is established, just terminate. */
+	struct ps_rab *rab = fi->priv;
+	struct osmo_pfcp_msg *m;
+
+	if (!(rab->up_f_seid.ip_addr.v4_present /* || rab->up_f_seid.ip_addr.v6_present */)) {
+		/* There is no valid PFCP session, so no need to send a Session Deletion Request */
+		ps_rab_fsm_state_chg(PS_RAB_ST_WAIT_USE_COUNT);
+		return;
+	}
+
+	m = ps_rab_new_pfcp_msg_req(rab, OSMO_PFCP_MSGT_SESSION_DEL_REQ);
+	m->ctx.resp_cb = on_pfcp_del_resp;
+	if (osmo_pfcp_endpoint_tx(g_hnbgw->pfcp.ep, m)) {
+		LOG_PS_RAB(rab, LOGL_ERROR, "Failed to send PFCP message\n");
+		ps_rab_failure(rab);
+	}
+}
+
+static int on_pfcp_del_resp(struct osmo_pfcp_msg *req, struct osmo_pfcp_msg *rx_resp, const char *errmsg)
+{
+	struct ps_rab *rab = req->ctx.session_fi->priv;
+	if (errmsg)
+		LOG_PS_RAB(rab, LOGL_ERROR, "PFCP Session Deletion Response: %s\n", errmsg);
+	osmo_fsm_inst_dispatch(rab->fi, PS_RAB_EV_PFCP_DEL_RESP, rx_resp);
+
+	/* By returning 0 here, the rx_resp message is not dispatched "again" to pfcp_ep->rx_msg(). We've handled it
+	 * here already. */
+	return 0;
+}
+
+static void ps_rab_fsm_wait_pfcp_del_resp(struct osmo_fsm_inst *fi, uint32_t event, void *data)
+{
+	switch (event) {
+	case PS_RAB_EV_PFCP_DEL_RESP:
+		/* All done, terminate. Even if the Session Deletion failed, there's nothing we can do about it. */
+		ps_rab_fsm_state_chg(PS_RAB_ST_WAIT_USE_COUNT);
+		return;
+	default:
+		OSMO_ASSERT(false);
+	}
+}
+
+static int ps_rab_fsm_use_cb(struct osmo_use_count_entry *e, int32_t old_use_count, const char *file, int line)
+{
+	struct ps_rab *rab = e->use_count->talloc_object;
+	if (!osmo_use_count_total(&rab->use_count))
+		osmo_fsm_inst_dispatch(rab->fi, PS_RAB_EV_USE_COUNT_ZERO, NULL);
+	return 0;
+}
+
+static void ps_rab_fsm_wait_use_count_onenter(struct osmo_fsm_inst *fi, uint32_t prev_state)
+{
+	struct ps_rab *rab = fi->priv;
+	if (rab->resp_fi)
+		osmo_fsm_inst_dispatch(rab->resp_fi, PS_RAB_ASS_EV_RAB_RELEASED, rab);
+	OSMO_ASSERT(osmo_use_count_get_put(&rab->use_count, PS_RAB_USE_ACTIVE, -1) == 0);
+}
+
+static void ps_rab_fsm_allstate_action(struct osmo_fsm_inst *fi, uint32_t event, void *data)
+{
+	switch (event) {
+
+	case PS_RAB_EV_USE_COUNT_ZERO:
+		if (fi->state == PS_RAB_ST_WAIT_USE_COUNT)
+			osmo_fsm_inst_term(fi, OSMO_FSM_TERM_REGULAR, NULL);
+		/* else, ignore. */
+		return;
+
+	default:
+		OSMO_ASSERT(false);
+	}
+}
+
+static void ps_rab_forget_map(struct ps_rab *rab)
+{
+	/* remove from map->ps_rab_list */
+	if (rab->map)
+		llist_del(&rab->entry);
+	rab->map = NULL;
+}
+
+static void ps_rab_fsm_cleanup(struct osmo_fsm_inst *fi, enum osmo_fsm_term_cause cause)
+{
+	struct ps_rab *rab = fi->priv;
+	ps_rab_forget_map(rab);
+}
+
+/* notify_fi can be NULL, in which case no event PS_RAB_ASS_EV_RAB_RELEASED event will be dispatched */
+void ps_rab_release(struct ps_rab *rab, struct osmo_fsm_inst *notify_fi)
+{
+	struct osmo_fsm_inst *fi = rab->fi;
+	ps_rab_forget_map(rab);
+	rab->resp_fi = notify_fi;
+	switch (fi->state) {
+	case PS_RAB_ST_RX_CORE_REMOTE_F_TEID:
+		/* No session requested yet. Nothing to be deleted. */
+		LOG_PS_RAB(rab, LOGL_NOTICE, "RAB release before PFCP Session Establishment Request, terminating\n");
+		ps_rab_fsm_state_chg(PS_RAB_ST_WAIT_USE_COUNT);
+		return;
+	case PS_RAB_ST_WAIT_PFCP_EST_RESP:
+		/* Session was requested via PFCP, but we only know the SEID to send in a deletion when the PFCP Session
+		 * Establishment Response arrives. */
+		rab->release_requested = true;
+		LOG_PS_RAB(rab, LOGL_ERROR, "RAB release while waiting for PFCP Session Establishment Response\n");
+		return;
+	default:
+		/* Session has been established (and we know the SEID). Initiate deletion. */
+		LOG_PS_RAB(rab, LOGL_INFO, "RAB release, deleting PFCP session\n");
+		ps_rab_fsm_state_chg(PS_RAB_ST_WAIT_PFCP_DEL_RESP);
+		return;
+	case PS_RAB_ST_WAIT_PFCP_DEL_RESP:
+		/* Already requested a PFCP Session Deletion. Nothing else to do, wait for the Deletion Response (or
+		 * timeout). */
+		LOG_PS_RAB(rab, LOGL_INFO, "RAB release while waiting for PFCP Session Deletion Response\n");
+		return;
+	case PS_RAB_ST_WAIT_USE_COUNT:
+		/* Already released, just wait for the last users (queued PFCP messages) to expire. */
+		LOG_PS_RAB(rab, LOGL_INFO, "RAB release, already waiting for deallocation\n");
+		return;
+	}
+}
+
+#define S(x) (1 << (x))
+
+static const struct osmo_fsm_state ps_rab_fsm_states[] = {
+	[PS_RAB_ST_RX_CORE_REMOTE_F_TEID] = {
+		.name = "RX_CORE_REMOTE_F_TEID",
+		.out_state_mask = 0
+			| S(PS_RAB_ST_WAIT_PFCP_EST_RESP)
+			| S(PS_RAB_ST_WAIT_USE_COUNT)
+			,
+	},
+	[PS_RAB_ST_WAIT_PFCP_EST_RESP] = {
+		.name = "WAIT_PFCP_EST_RESP",
+		.onenter = ps_rab_fsm_wait_pfcp_est_resp_onenter,
+		.action = ps_rab_fsm_wait_pfcp_est_resp,
+		.in_event_mask = 0
+			| S(PS_RAB_EV_PFCP_EST_RESP)
+			,
+		.out_state_mask = 0
+			| S(PS_RAB_ST_WAIT_ACCESS_REMOTE_F_TEID)
+			| S(PS_RAB_ST_WAIT_USE_COUNT)
+			,
+	},
+	[PS_RAB_ST_WAIT_ACCESS_REMOTE_F_TEID] = {
+		.name = "WAIT_ACCESS_REMOTE_F_TEID",
+		.action = ps_rab_fsm_wait_access_remote_f_teid,
+		.in_event_mask = 0
+			| S(PS_RAB_EV_RX_ACCESS_REMOTE_F_TEID)
+			,
+		.out_state_mask = 0
+			| S(PS_RAB_ST_WAIT_PFCP_MOD_RESP)
+			| S(PS_RAB_ST_WAIT_PFCP_DEL_RESP)
+			| S(PS_RAB_ST_WAIT_USE_COUNT)
+			,
+	},
+	[PS_RAB_ST_WAIT_PFCP_MOD_RESP] = {
+		.name = "WAIT_PFCP_MOD_RESP",
+		.onenter = ps_rab_fsm_wait_pfcp_mod_resp_onenter,
+		.action = ps_rab_fsm_wait_pfcp_mod_resp,
+		.in_event_mask = 0
+			| S(PS_RAB_EV_PFCP_MOD_RESP)
+			,
+		.out_state_mask = 0
+			| S(PS_RAB_ST_ESTABLISHED)
+			| S(PS_RAB_ST_WAIT_PFCP_DEL_RESP)
+			| S(PS_RAB_ST_WAIT_USE_COUNT)
+			,
+	},
+	[PS_RAB_ST_ESTABLISHED] = {
+		.name = "ESTABLISHED",
+		.onenter = ps_rab_fsm_established_onenter,
+		.out_state_mask = 0
+			| S(PS_RAB_ST_WAIT_PFCP_DEL_RESP)
+			| S(PS_RAB_ST_WAIT_USE_COUNT)
+			,
+	},
+	[PS_RAB_ST_WAIT_PFCP_DEL_RESP] = {
+		.name = "WAIT_PFCP_DEL_RESP",
+		.onenter = ps_rab_fsm_wait_pfcp_del_resp_onenter,
+		.action = ps_rab_fsm_wait_pfcp_del_resp,
+		.in_event_mask = 0
+			| S(PS_RAB_EV_PFCP_DEL_RESP)
+			,
+		.out_state_mask = 0
+			| S(PS_RAB_ST_WAIT_USE_COUNT)
+			,
+	},
+	[PS_RAB_ST_WAIT_USE_COUNT] = {
+		.name = "WAIT_USE_COUNT",
+		.onenter = ps_rab_fsm_wait_use_count_onenter,
+		.in_event_mask = 0
+			| S(PS_RAB_EV_USE_COUNT_ZERO)
+			,
+	},
+};
+
+static struct osmo_fsm ps_rab_fsm = {
+	.name = "ps_rab",
+	.states = ps_rab_fsm_states,
+	.num_states = ARRAY_SIZE(ps_rab_fsm_states),
+	.log_subsys = DLPFCP,
+	.event_names = ps_rab_fsm_event_names,
+	.cleanup = ps_rab_fsm_cleanup,
+	.allstate_event_mask = S(PS_RAB_EV_USE_COUNT_ZERO),
+	.allstate_action = ps_rab_fsm_allstate_action,
+};
+
+static __attribute__((constructor)) void ps_rab_fsm_register(void)
+{
+	OSMO_ASSERT(osmo_fsm_register(&ps_rab_fsm) == 0);
+}

src/osmo-hnbgw/ranap_rab_ass.c

@@ -0,0 +1,625 @@
+/* (C) 2021 by sysmocom s.f.m.c. GmbH <info@sysmocom.de>
+ * All Rights Reserved
+ *
+ * Author: Philipp Maier
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+/* Note: This files contains tools to decode and re-encode the RAB-AssignmentRequest. This set of tools is used by
+ * mgcp_fsm.c to extract and manipulate the transportLayerAddress. */
+
+#include <errno.h>
+#include <osmocom/core/utils.h>
+#include <osmocom/core/logging.h>
+#include <osmocom/core/sockaddr_str.h>
+#include <osmocom/hnbgw/hnbgw.h>
+#include <osmocom/ranap/ranap_common.h>
+#include <osmocom/ranap/ranap_common_cn.h>
+#include <osmocom/ranap/ranap_common_ran.h>
+#include <osmocom/ranap/iu_helpers.h>
+#include <asn1c/asn1helpers.h>
+
+/*! Encode RABAP RAB AssignmentRequest from RANAP_RAB_AssignmentRequestIEs.
+ *  \ptmap[out] data user provided memory to store resulting ASN.1 encoded message.
+ *  \ptmap[in] len length of user provided memory to store resulting ASN.1 encoded message.
+ *  \ptmap[in] ies user provided memory with RANAP_RAB_AssignmentRequestIEs.
+ *  \returns resulting message length on success; negative on error. */
+struct msgb *ranap_rab_ass_req_encode(RANAP_RAB_AssignmentRequestIEs_t *rab_assignment_request_ies)
+{
+	int rc;
+	struct msgb *msg;
+	RANAP_RAB_AssignmentRequest_t _rab_assignment_request = { 0 };
+	RANAP_RAB_AssignmentRequest_t *rab_assignment_request = &_rab_assignment_request;
+
+	rc = ranap_encode_rab_assignmentrequesties(rab_assignment_request, rab_assignment_request_ies);
+	if (rc < 0)
+		return NULL;
+
+	/* generate an Initiating Mesasage */
+	msg = ranap_generate_initiating_message(RANAP_ProcedureCode_id_RAB_Assignment,
+						RANAP_Criticality_reject,
+						&asn_DEF_RANAP_RAB_AssignmentRequest, rab_assignment_request);
+
+	/* 'msg' has been generated, we cann now release the input 'out' */
+	ASN_STRUCT_FREE_CONTENTS_ONLY(asn_DEF_RANAP_RAB_AssignmentRequest, rab_assignment_request);
+
+	return msg;
+}
+
+/*! Encode RABAP RAB AssignmentRequest from RANAP_RAB_AssignmentResponseIEs.
+ *  \ptmap[out] data user provided memory to store resulting ASN.1 encoded message.
+ *  \ptmap[in] len length of user provided memory to store resulting ASN.1 encoded message.
+ *  \ptmap[in] ies user provided memory with RANAP_RAB_AssignmentResponseIEs.
+ *  \returns resulting message length on success; negative on error. */
+int ranap_rab_ass_resp_encode(uint8_t *data, unsigned int len,
+			      RANAP_RAB_AssignmentResponseIEs_t *rab_assignment_response_ies)
+{
+	int rc;
+	struct msgb *msg;
+
+	RANAP_RAB_AssignmentResponse_t _rab_assignment_response = { 0 };
+	RANAP_RAB_AssignmentResponse_t *rab_assignment_response = &_rab_assignment_response;
+
+	memset(data, 0, len);
+
+	rc = ranap_encode_rab_assignmentresponseies(rab_assignment_response, rab_assignment_response_ies);
+	if (rc < 0)
+		return -EINVAL;
+
+	/* generate an outcome mesasage */
+	msg = ranap_generate_outcome(RANAP_ProcedureCode_id_RAB_Assignment,
+				     RANAP_Criticality_reject,
+				     &asn_DEF_RANAP_RAB_AssignmentResponse, rab_assignment_response);
+
+	/* 'msg' has been generated, we can now release the input 'rab_assignment_response' */
+	ASN_STRUCT_FREE_CONTENTS_ONLY(asn_DEF_RANAP_RAB_AssignmentResponse, rab_assignment_response);
+
+	if (!msg)
+		return -EINVAL;
+	if (msg->len > len)
+		return -EINVAL;
+
+	memcpy(data, msg->data, msg->len);
+	rc = msg->len;
+	msgb_free(msg);
+	return rc;
+}
+
+/* Pick the indexed item from the RAB setup-or-modify list and return the first protocol-ie-field-pair. */
+static RANAP_ProtocolIE_FieldPair_t *prot_ie_field_pair_from_ass_req_ies(const RANAP_RAB_AssignmentRequestIEs_t *ies,
+									 unsigned int index)
+{
+	RANAP_ProtocolIE_ContainerPair_t *protocol_ie_container_pair;
+	RANAP_ProtocolIE_FieldPair_t *protocol_ie_field_pair;
+
+	/* Make sure we indeed deal with a setup-or-modify list */
+	if (!(ies->presenceMask & RAB_ASSIGNMENTREQUESTIES_RANAP_RAB_SETUPORMODIFYLIST_PRESENT)) {
+		RANAP_DEBUG
+		    ("Decoding failed, the RANAP RAB AssignmentRequest did not contain a setup-or-modify list!\n");
+		return NULL;
+	}
+
+	/* Detect the end of the list */
+	if (index >= ies->raB_SetupOrModifyList.list.count)
+		return NULL;
+
+	protocol_ie_container_pair = ies->raB_SetupOrModifyList.list.array[index];
+	protocol_ie_field_pair = protocol_ie_container_pair->list.array[0];
+
+	return protocol_ie_field_pair;
+}
+
+/* Pick the indexed item from the RAB release-list list and return a pointer to it */
+static RANAP_IE_t *release_item_from_ass_req_ies(const RANAP_RAB_AssignmentRequestIEs_t *ies, unsigned int index)
+{
+	/* Make sure we indeed deal with a setup-or-modify list */
+	if (!(ies->presenceMask & RAB_ASSIGNMENTREQUESTIES_RANAP_RAB_RELEASELIST_PRESENT)) {
+		RANAP_DEBUG
+		    ("Decoding failed, the RANAP RAB AssignmentRequest did not contain a release list!\n");
+		return NULL;
+	}
+
+	/* Detect the end of the list */
+	if (index >= ies->raB_ReleaseList.raB_ReleaseList_ies.list.count)
+		return NULL;
+
+	return ies->raB_ReleaseList.raB_ReleaseList_ies.list.array[index];
+}
+
+/* Pick the indexed item from the RAB setup-or-modified list and return a pointer to it */
+static RANAP_IE_t *setup_or_modif_item_from_rab_ass_resp(const RANAP_RAB_AssignmentResponseIEs_t *ies,
+							 unsigned int index)
+{
+	/* Make sure we indeed deal with a setup-or-modified list */
+	if (!(ies->presenceMask & RAB_ASSIGNMENTRESPONSEIES_RANAP_RAB_SETUPORMODIFIEDLIST_PRESENT)) {
+		RANAP_DEBUG("RANAP RAB AssignmentResponse did not contain a setup-or-modified list!\n");
+		return NULL;
+	}
+
+	/* Detect the end of the list */
+	if (index >= ies->raB_SetupOrModifiedList.raB_SetupOrModifiedList_ies.list.count)
+		return NULL;
+
+	return ies->raB_SetupOrModifiedList.raB_SetupOrModifiedList_ies.list.array[index];
+}
+
+/* Pick the indexed item from the RAB failed list and return a pointer to it */
+static RANAP_IE_t *failed_list_item_from_rab_ass_resp(const RANAP_RAB_AssignmentResponseIEs_t *ies,
+						      unsigned int index)
+{
+	/* Make sure we indeed deal with a failed list */
+	if (!(ies->presenceMask & RAB_ASSIGNMENTRESPONSEIES_RANAP_RAB_FAILEDLIST_PRESENT)) {
+		RANAP_DEBUG("RANAP RAB AssignmentResponse did not contain a failed list!\n");
+		return NULL;
+	}
+
+	/* Detect the end of the list */
+	if (index >= ies->raB_FailedList.raB_FailedList_ies.list.count)
+		return NULL;
+
+	return ies->raB_FailedList.raB_FailedList_ies.list.array[index];
+}
+
+/* Find the RAB specified by rab_id in ies, decode the result into items_ies and return a positive index.
+ * The caller is responsible for freeing the contents in items_ies. In case of failure, the return code
+ * will be negative. */
+static int decode_rab_smditms_from_resp_ies(RANAP_RAB_SetupOrModifiedItemIEs_t *items_ies,
+					    RANAP_RAB_AssignmentResponseIEs_t *ies, uint8_t rab_id)
+{
+	RANAP_IE_t *setup_or_modified_list_ie;
+	RANAP_RAB_SetupOrModifiedItem_t *rab_setup_or_modified_item;
+	int rc;
+	uint8_t rab_id_decoded;
+	unsigned int index = 0;
+
+	while (1) {
+		setup_or_modified_list_ie = setup_or_modif_item_from_rab_ass_resp(ies, index);
+		if (!setup_or_modified_list_ie)
+			return -EINVAL;
+
+		rc = ranap_decode_rab_setupormodifieditemies_fromlist(items_ies, &setup_or_modified_list_ie->value);
+		if (rc < 0)
+			return -EINVAL;
+
+		rab_setup_or_modified_item = &items_ies->raB_SetupOrModifiedItem;
+		/* The RAB-ID is defined as a bitstring with a size of 8 (1 byte),
+		 * See also RANAP-IEs.asn, RAB-ID ::= BIT STRING (SIZE (8)) */
+		rab_id_decoded = rab_setup_or_modified_item->rAB_ID.buf[0];
+		if (rab_id_decoded == rab_id)
+			return index;
+
+		ASN_STRUCT_FREE_CONTENTS_ONLY(asn_DEF_RANAP_RAB_SetupOrModifiedItem, items_ies);
+		index++;
+	}
+}
+
+/* See comment above decode_rab_smditms_from_resp_ies() */
+static int decode_rab_flitms_from_resp_ies(RANAP_RAB_FailedItemIEs_t *items_ies,
+					   RANAP_RAB_AssignmentResponseIEs_t *ies, uint8_t rab_id)
+{
+	RANAP_IE_t *failed_list_ie;
+	RANAP_RAB_FailedItem_t *rab_failed_item;
+	int rc;
+	uint8_t rab_id_decoded;
+	unsigned int index = 0;
+
+	while (1) {
+		failed_list_ie = failed_list_item_from_rab_ass_resp(ies, index);
+		if (!failed_list_ie)
+			return -EINVAL;
+
+		rc = ranap_decode_rab_faileditemies_fromlist(items_ies, &failed_list_ie->value);
+		if (rc < 0)
+			return -EINVAL;
+
+		rab_failed_item = &items_ies->raB_FailedItem;
+		/* The RAB-ID is defined as a bitstring with a size of 8 (1 byte),
+		 * See also RANAP-IEs.asn, RAB-ID ::= BIT STRING (SIZE (8)) */
+		rab_id_decoded = rab_failed_item->rAB_ID.buf[0];
+		if (rab_id_decoded == rab_id)
+			return index;
+
+		ASN_STRUCT_FREE_CONTENTS_ONLY(asn_DEF_RANAP_RAB_FailedItem, items_ies);
+		index++;
+	}
+}
+
+/* find the RAB specified by rab_id in ies and when found, decode the result into item */
+static int decode_rab_smditms_from_req_ies(RANAP_RAB_SetupOrModifyItemFirst_t *item,
+					   RANAP_RAB_AssignmentRequestIEs_t *ies, uint8_t rab_id)
+{
+	RANAP_ProtocolIE_FieldPair_t *protocol_ie_field_pair;
+	int rc;
+	uint8_t rab_id_decoded;
+	unsigned int index = 0;
+
+	while (1) {
+		protocol_ie_field_pair = prot_ie_field_pair_from_ass_req_ies(ies, index);
+		if (!protocol_ie_field_pair)
+			return -EINVAL;
+
+		if (protocol_ie_field_pair->id != RANAP_ProtocolIE_ID_id_RAB_SetupOrModifyItem) {
+			RANAP_DEBUG
+			    ("Decoding failed, the protocol IE field-pair is not of type RANAP RAB setup-or-modify-item!\n");
+			return -EINVAL;
+		}
+
+		rc = ranap_decode_rab_setupormodifyitemfirst(item, &protocol_ie_field_pair->firstValue);
+		if (rc < 0)
+			return -EINVAL;
+
+		rab_id_decoded = item->rAB_ID.buf[0];
+		if (rab_id_decoded == rab_id)
+			return index;
+	}
+}
+
+static int decode_rab_relitms_from_req_ies(RANAP_RAB_ReleaseItemIEs_t *items_ies,
+					   RANAP_RAB_AssignmentRequestIEs_t *ies, uint8_t rab_id)
+{
+	RANAP_IE_t *release_list_ie;
+	RANAP_RAB_ReleaseItem_t *rab_release_item;
+	int rc;
+	uint8_t rab_id_decoded;
+	unsigned int index = 0;
+
+	while (1) {
+		release_list_ie = release_item_from_ass_req_ies(ies, index);
+		if (!release_list_ie)
+			return -EINVAL;
+
+		if (release_list_ie->id != RANAP_ProtocolIE_ID_id_RAB_ReleaseItem) {
+			RANAP_DEBUG("Decoding failed, the protocol IE is not of type RANAP RAB ReleaseItem!\n");
+			return -EINVAL;
+		}
+
+		rc = ranap_decode_rab_releaseitemies_fromlist(items_ies, &release_list_ie->value);
+		if (rc < 0)
+			return -EINVAL;
+
+		rab_release_item = &items_ies->raB_ReleaseItem;
+		/* The RAB-ID is defined as a bitstring with a size of 8 (1 byte),
+		 * See also RANAP-IEs.asn, RAB-ID ::= BIT STRING (SIZE (8)) */
+		rab_id_decoded = rab_release_item->rAB_ID.buf[0];
+		if (rab_id_decoded == rab_id)
+			return index;
+
+		ASN_STRUCT_FREE_CONTENTS_ONLY(asn_DEF_RANAP_RAB_ReleaseItem, items_ies);
+		index++;
+	}
+}
+
+/*! Extract IP address and port from RANAP_RAB_AssignmentRequestIEs.
+ *  \ptmap[out] addr user provided memory to store extracted RTP stream IP-Address and port number.
+ *  \ptmap[out] rab_id pointer to store RAB-ID (optional, can be NULL).
+ *  \ptmap[in] ies user provided memory with RANAP_RAB_AssignmentRequestIEs.
+ *  \ptmap[in] index index of the SetupOrModifyItem (e.g. 0 for the first list item).
+ *  \returns 0 on success; negative on error. */
+int ranap_rab_ass_req_ies_extract_inet_addr(struct osmo_sockaddr *addr, uint8_t *rab_id,
+					    RANAP_RAB_AssignmentRequestIEs_t *ies, unsigned int index)
+{
+	RANAP_ProtocolIE_FieldPair_t *protocol_ie_field_pair;
+	RANAP_RAB_SetupOrModifyItemFirst_t _rab_setup_or_modify_item_first = { 0 };
+	RANAP_RAB_SetupOrModifyItemFirst_t *rab_setup_or_modify_item_first = &_rab_setup_or_modify_item_first;
+	RANAP_TransportLayerAddress_t *trasp_layer_addr;
+	RANAP_IuTransportAssociation_t *transp_assoc;
+	uint16_t port;
+	int rc;
+
+	protocol_ie_field_pair = prot_ie_field_pair_from_ass_req_ies(ies, index);
+	if (!protocol_ie_field_pair)
+		return -EINVAL;
+
+	if (protocol_ie_field_pair->id != RANAP_ProtocolIE_ID_id_RAB_SetupOrModifyItem) {
+		RANAP_DEBUG
+		    ("Decoding failed, the protocol IE field-pair is not of type RANAP RAB setup-or-modify-item!\n");
+		return -EINVAL;
+	}
+
+	rc = ranap_decode_rab_setupormodifyitemfirst(rab_setup_or_modify_item_first,
+						     &protocol_ie_field_pair->firstValue);
+	if (rc < 0)
+		return -EINVAL;
+
+	if (rab_id) {
+		/* The RAB-ID is defined as a bitstring with a size of 8 (1 byte),
+		 * See also RANAP-IEs.asn, RAB-ID ::= BIT STRING (SIZE (8)) */
+		*rab_id = rab_setup_or_modify_item_first->rAB_ID.buf[0];
+	}
+
+	/* Decode IP-Address */
+	trasp_layer_addr = &rab_setup_or_modify_item_first->transportLayerInformation->transportLayerAddress;
+	rc = ranap_transp_layer_addr_decode2(addr, NULL, trasp_layer_addr);
+	if (rc < 0) {
+		rc = -EINVAL;
+		goto error;
+	}
+
+	/* Decode port number */
+	transp_assoc = &rab_setup_or_modify_item_first->transportLayerInformation->iuTransportAssociation;
+	rc = ranap_transp_assoc_decode(&port, transp_assoc);
+	if (rc < 0) {
+		rc = -EINVAL;
+		goto error;
+	}
+
+	switch (addr->u.sin.sin_family) {
+	case AF_INET:
+		addr->u.sin.sin_port = htons(port);
+		break;
+	case AF_INET6:
+		addr->u.sin6.sin6_port = htons(port);
+		break;
+	default:
+		rc = -EINVAL;
+		goto error;
+	}
+
+	rc = 0;
+error:
+	ASN_STRUCT_FREE_CONTENTS_ONLY(asn_DEF_RANAP_RAB_SetupOrModifyItemFirst, rab_setup_or_modify_item_first);
+	return rc;
+}
+
+/*! Extract IP address and port from RANAP_RAB_AssignmentResponseIEs.
+ *  \ptmap[out] addr user provided memory to store extracted RTP stream IP-Address and port number.
+ *  \ptmap[in] ies user provided memory with RANAP_RAB_AssignmentResponseIEs.
+ *  \ptmap[in] rab_id expected rab id to look for.
+ *  \returns 0 on success; negative on error. */
+int ranap_rab_ass_resp_ies_extract_inet_addr(struct osmo_sockaddr *addr, RANAP_RAB_AssignmentResponseIEs_t *ies, uint8_t rab_id)
+{
+	RANAP_RAB_SetupOrModifiedItemIEs_t _rab_setup_or_modified_items_ies = { 0 };
+	RANAP_RAB_SetupOrModifiedItemIEs_t *rab_setup_or_modified_items_ies = &_rab_setup_or_modified_items_ies;
+	RANAP_RAB_SetupOrModifiedItem_t *rab_setup_or_modified_item;
+	uint16_t port;
+	int rc;
+
+	rc = decode_rab_smditms_from_resp_ies(rab_setup_or_modified_items_ies, ies, rab_id);
+	if (rc < 0)
+		return -EINVAL;
+
+	rab_setup_or_modified_item = &rab_setup_or_modified_items_ies->raB_SetupOrModifiedItem;
+
+	/* Decode IP-Address */
+	rc = ranap_transp_layer_addr_decode2(addr, NULL, rab_setup_or_modified_item->transportLayerAddress);
+	if (rc < 0) {
+		rc = -EINVAL;
+		goto error;
+	}
+
+	/* Decode port number */
+	rc = ranap_transp_assoc_decode(&port, rab_setup_or_modified_item->iuTransportAssociation);
+	if (rc < 0) {
+		rc = -EINVAL;
+		goto error;
+	}
+
+	switch (addr->u.sin.sin_family) {
+	case AF_INET:
+		addr->u.sin.sin_port = htons(port);
+		break;
+	case AF_INET6:
+		addr->u.sin6.sin6_port = htons(port);
+		break;
+	default:
+		rc = -EINVAL;
+		goto error;
+	}
+
+	rc = 0;
+error:
+	ASN_STRUCT_FREE_CONTENTS_ONLY(asn_DEF_RANAP_RAB_SetupOrModifiedItem, rab_setup_or_modified_items_ies);
+	return rc;
+}
+
+/*! Replace IP address and port in RANAP_RAB_AssignmentRequestIEs.
+ *  \ptmap[inout] ies user provided memory with RANAP_RAB_AssignmentRequestIEs.
+ *  \ptmap[in] addr user provided memory that contains the new RTP stream IP-Address and port number.
+ *  \ptmap[in] rab_id expected rab id to look for.
+ *  \returns 0 on success; negative on error. */
+int ranap_rab_ass_req_ies_replace_inet_addr(RANAP_RAB_AssignmentRequestIEs_t *ies, struct osmo_sockaddr *addr, uint8_t rab_id)
+{
+	RANAP_ProtocolIE_FieldPair_t *protocol_ie_field_pair;
+	RANAP_RAB_SetupOrModifyItemFirst_t _rab_setup_or_modify_item_first = { 0 };
+	RANAP_RAB_SetupOrModifyItemFirst_t *rab_setup_or_modify_item_first = &_rab_setup_or_modify_item_first;
+	RANAP_TransportLayerInformation_t *old_transport_layer_information = NULL;
+	RANAP_TransportLayerInformation_t *new_transport_layer_information = NULL;
+	struct osmo_sockaddr addr_old;
+	bool uses_x213_nsap;
+	int rc;
+	int index;
+
+	index = decode_rab_smditms_from_req_ies(rab_setup_or_modify_item_first, ies, rab_id);
+	if (index < 0)
+		return -EINVAL;
+
+	/* Replace transport-layer-information */
+	if (rab_setup_or_modify_item_first->transportLayerInformation->iuTransportAssociation.present ==
+	    RANAP_IuTransportAssociation_PR_bindingID) {
+		old_transport_layer_information = rab_setup_or_modify_item_first->transportLayerInformation;
+
+		/* Before we can re-encode the transport layer information, we need to know the format it was
+		 * encoded in. */
+		rc = ranap_transp_layer_addr_decode2(&addr_old, &uses_x213_nsap,
+						     &old_transport_layer_information->transportLayerAddress);
+		if (rc < 0) {
+			rc = -EINVAL;
+			goto error;
+		}
+
+		/* Encode a new transport layer information field */
+		new_transport_layer_information = ranap_new_transp_info_rtp(addr, uses_x213_nsap);
+		if (!new_transport_layer_information) {
+			rc = -EINVAL;
+			goto error;
+		}
+
+		rab_setup_or_modify_item_first->transportLayerInformation = new_transport_layer_information;
+	} else {
+		RANAP_DEBUG("Rewriting transport layer information failed, no bindingID (port)!\n");
+		rc = -EINVAL;
+		goto error;
+	}
+
+	/* Reencode transport-layer-information */
+	protocol_ie_field_pair = prot_ie_field_pair_from_ass_req_ies(ies, index);
+	rc = ANY_fromType_aper(&protocol_ie_field_pair->firstValue, &asn_DEF_RANAP_RAB_SetupOrModifyItemFirst,
+			       rab_setup_or_modify_item_first);
+	if (rc < 0) {
+		RANAP_DEBUG("Rewriting transport layer information failed, could not reencode\n");
+		rc = -EINVAL;
+		goto error;
+	}
+
+error:
+	/* Restore original state of the modified ASN.1 struct so that the asn1c free mechanisms can work properly */
+	if (old_transport_layer_information)
+		rab_setup_or_modify_item_first->transportLayerInformation = old_transport_layer_information;
+
+	ASN_STRUCT_FREE_CONTENTS_ONLY(asn_DEF_RANAP_RAB_SetupOrModifyItemFirst, rab_setup_or_modify_item_first);
+	if (new_transport_layer_information)
+		ASN_STRUCT_FREE(asn_DEF_RANAP_TransportLayerInformation, new_transport_layer_information);
+	return rc;
+}
+
+/*! Replace IP address and port in RANAP_RAB_AssignmentResponseIEs.
+ *  \ptmap[inout] ies user provided memory with RANAP_RAB_AssignmentResponseIEs.
+ *  \ptmap[in] addr user provided memory that contains the new RTP stream IP-Address and port number.
+ *  \ptmap[in] rab_id expected rab id to look for.
+ *  \returns 0 on success; negative on error. */
+int ranap_rab_ass_resp_ies_replace_inet_addr(RANAP_RAB_AssignmentResponseIEs_t *ies, struct osmo_sockaddr *addr, uint8_t rab_id)
+{
+	RANAP_IE_t *setup_or_modified_list_ie;
+	RANAP_RAB_SetupOrModifiedItemIEs_t _rab_setup_or_modified_items_ies = { 0 };
+	RANAP_RAB_SetupOrModifiedItemIEs_t *rab_setup_or_modified_items_ies = &_rab_setup_or_modified_items_ies;
+	RANAP_RAB_SetupOrModifiedItem_t *rab_setup_or_modified_item;
+	RANAP_TransportLayerInformation_t *temp_transport_layer_information = NULL;
+	RANAP_TransportLayerAddress_t *old_transport_layer_address = NULL;
+	RANAP_IuTransportAssociation_t *old_iu_transport_association = NULL;
+	struct osmo_sockaddr addr_old;
+	bool uses_x213_nsap;
+	int rc;
+	int index;
+
+	index = decode_rab_smditms_from_resp_ies(rab_setup_or_modified_items_ies, ies, rab_id);
+	if (index < 0)
+		return -EINVAL;
+
+	rab_setup_or_modified_item = &rab_setup_or_modified_items_ies->raB_SetupOrModifiedItem;
+
+	/* Before we can re-encode the transport layer address, we need to know the format it was encoded in. */
+	rc = ranap_transp_layer_addr_decode2(&addr_old, &uses_x213_nsap,
+					     rab_setup_or_modified_item->transportLayerAddress);
+	if (rc < 0) {
+		rc = -EINVAL;
+		goto error;
+	}
+
+	/* Generate a temporary transport layer information, from which we can use the transport layer address and
+	 * the iu transport association to update the setup or modified item */
+	temp_transport_layer_information = ranap_new_transp_info_rtp(addr, uses_x213_nsap);
+	if (!temp_transport_layer_information) {
+		rc = -EINVAL;
+		goto error;
+	}
+
+	/* Replace transport layer address and iu transport association */
+	old_transport_layer_address = rab_setup_or_modified_item->transportLayerAddress;
+	old_iu_transport_association = rab_setup_or_modified_item->iuTransportAssociation;
+	rab_setup_or_modified_item->transportLayerAddress = &temp_transport_layer_information->transportLayerAddress;
+	rab_setup_or_modified_item->iuTransportAssociation = &temp_transport_layer_information->iuTransportAssociation;
+
+	/* Reencode modified setup or modified list */
+	setup_or_modified_list_ie = setup_or_modif_item_from_rab_ass_resp(ies, index);
+	rc = ANY_fromType_aper(&setup_or_modified_list_ie->value, &asn_DEF_RANAP_RAB_SetupOrModifiedItem,
+			       rab_setup_or_modified_items_ies);
+	if (rc < 0) {
+		RANAP_DEBUG("Rewriting transport layer address failed, could not reencode\n");
+		rc = -EINVAL;
+		goto error;
+	}
+
+error:
+	/* Restore original state of the modified ASN.1 struct so that the asn1c free mechanisms can work properly */
+	if (old_transport_layer_address)
+		rab_setup_or_modified_item->transportLayerAddress = old_transport_layer_address;
+	if (old_iu_transport_association)
+		rab_setup_or_modified_item->iuTransportAssociation = old_iu_transport_association;
+	if (temp_transport_layer_information)
+		ASN_STRUCT_FREE(asn_DEF_RANAP_TransportLayerInformation, temp_transport_layer_information);
+
+	ASN_STRUCT_FREE_CONTENTS_ONLY(asn_DEF_RANAP_RAB_SetupOrModifiedItem, rab_setup_or_modified_items_ies);
+
+	return rc;
+}
+
+/*! Check if a specific RAB is present in an RAB-Failed-Item-List inside RANAP_RAB_AssignmentResponseIEs.
+ *  \ptmap[in] ies user provided memory with RANAP_RAB_AssignmentResponseIEs.
+ *  \ptmap[in] rab_id expected rab id to look for.
+ *  \returns true when RAB could be identified as failed; false otherwise */
+bool ranap_rab_ass_resp_ies_check_failure(RANAP_RAB_AssignmentResponseIEs_t *ies, uint8_t rab_id)
+{
+	RANAP_RAB_FailedItemIEs_t _rab_failed_items_ies = { 0 };
+	RANAP_RAB_FailedItemIEs_t *rab_failed_items_ies = &_rab_failed_items_ies;
+	int rc;
+
+	/* If we can get a failed item (rc >= 0) for the specified RAB ID, then we know that the
+	 * HNB reported the RAB Assignment as failed */
+	rc = decode_rab_flitms_from_resp_ies(rab_failed_items_ies, ies, rab_id);
+	if (rc < 0)
+		return false;
+
+	ASN_STRUCT_FREE_CONTENTS_ONLY(asn_DEF_RANAP_RAB_FailedItem, rab_failed_items_ies);
+
+	return true;
+}
+
+/*! Check if a specific RAB is present in an RAB-ReleaseList inside RANAP_RAB_AssignmentRequestIEs.
+ *  \ptmap[in] ies user provided memory with RANAP_RAB_AssignmentRequestIEs.
+ *  \ptmap[in] rab_id expected rab id to look for.
+ *  \returns true when RAB is intended for release; false otherwise */
+bool ranap_rab_ass_req_ies_check_release(RANAP_RAB_AssignmentRequestIEs_t *ies, uint8_t rab_id)
+{
+	RANAP_RAB_ReleaseItemIEs_t _rab_release_items_ies = { 0 };
+	RANAP_RAB_ReleaseItemIEs_t *rab_release_items_ies = &_rab_release_items_ies;
+	int rc;
+	bool result = true;
+
+	/* If we can get a rlease list item for the specified RAB ID, then we know that the
+	 * MSC intends to release the specified RAB */
+	rc = decode_rab_relitms_from_req_ies(rab_release_items_ies, ies, rab_id);
+	if (rc < 0)
+		result = false;
+
+	ASN_STRUCT_FREE_CONTENTS_ONLY(asn_DEF_RANAP_RAB_ReleaseItem, rab_release_items_ies);
+
+	return result;
+}
+
+/*! Find out how many RAB items are present in a RAB-SetupOrModifyList inside RANAP_RAB_AssignmentRequestIEs.
+ *  \ptmap[in] ies user provided memory with RANAP_RAB_AssignmentRequestIEs.
+ *  \returns number of RAB items, -1 on failure. */
+int ranap_rab_ass_req_ies_get_count(RANAP_RAB_AssignmentRequestIEs_t *ies)
+{
+	/* Make sure we indeed deal with a setup-or-modify list */
+	if (!(ies->presenceMask & RAB_ASSIGNMENTREQUESTIES_RANAP_RAB_SETUPORMODIFYLIST_PRESENT)) {
+		RANAP_DEBUG
+		    ("Decoding failed, the RANAP RAB AssignmentRequest did not contain a setup-or-modify list!\n");
+		return -1;
+	}
+
+	return ies->raB_SetupOrModifyList.list.count;
+}

src/osmo-hnbgw/tdefs.c

@@ -0,0 +1,56 @@
+/* (C) 2021 by sysmocom s.f.m.c. GmbH <info@sysmocom.de>
+ * All Rights Reserved
+ *
+ * Author: Philipp Maier
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ */
+
+#include "config.h"
+
+#include <osmocom/hnbgw/tdefs.h>
+
+#if ENABLE_PFCP
+#include <osmocom/pfcp/pfcp_endpoint.h>
+#endif
+
+struct osmo_tdef mgw_fsm_T_defs[] = {
+	{.T = -1001, .default_val = 5, .desc = "Timeout for HNB side call-leg (to-HNB) creation" },
+	{.T = -1002, .default_val = 10, .desc = "Timeout for the HNB to respond to RAB Assignment Request" },
+	{.T = -1003, .default_val = 5, .desc = "Timeout for HNB side call-leg (to-HNB) completion" },
+	{.T = -1004, .default_val = 5, .desc = "Timeout for MSC side call-leg (to-MSC) completion" },
+	{.T = -2427, .default_val = 5, .desc = "timeout for MGCP response from MGW" },
+	{ }
+};
+
+struct osmo_tdef hnbgw_T_defs[] = {
+	{.T = 3113, .default_val = 15, .desc = "Time to keep Paging record, for CN pools with more than one link" },
+	{.T = 4, .default_val = 5, .desc = "Timeout to receive RANAP RESET ACKNOWLEDGE from an MSC/SGSN" },
+	{.T = -31, .default_val = 15, .desc = "Timeout for establishing and releasing context maps (RUA <-> SCCP)" },
+	{.T = -34, .default_val = 1000, .unit = OSMO_TDEF_MS, .desc = "Period to query network traffic stats from netfilter" },
+	{
+		.T = -35,
+		.default_val = 60*60*24*7,
+		.desc = "Clean up all hNodeB persistent state after this time of the hNodeB being disconnected."
+			" Set to zero to never clear hNodeB persistent state. (default is 60*60*24*27 = a week)",
+	},
+	{.T = -1002, .default_val = 10, .desc = "Timeout for the HNB to respond to PS RAB Assignment Request" },
+	{ }
+};
+
+struct osmo_tdef_group hnbgw_tdef_group[] = {
+	{.name = "mgw", .tdefs = mgw_fsm_T_defs, .desc = "MGW (Media Gateway) interface" },
+	{.name = "hnbgw", .tdefs = hnbgw_T_defs, .desc = "Timers" },
+#if ENABLE_PFCP
+	{.name = "pfcp", .tdefs = osmo_pfcp_tdefs, .desc = "PFCP timers" },
+#endif
+	{ }
+};

src/osmo-hnbgw/umts_cell_id.c

@@ -0,0 +1,107 @@
+/* UMTS Cell ID */
+
+/* (C) 2015,2024 by Harald Welte <laforge@gnumonks.org>
+ * (C) 2016-2025 by sysmocom s.f.m.c. GmbH <info@sysmocom.de>
+ * All Rights Reserved
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+ #include "config.h"
+
+#include <unistd.h>
+#include <errno.h>
+#include <inttypes.h>
+
+#include <osmocom/core/talloc.h>
+#include <osmocom/core/utils.h>
+#include <osmocom/core/jhash.h>
+
+#include <osmocom/gsm/gsm23003.h>
+
+#include <osmocom/hnbgw/umts_cell_id.h>
+
+int umts_cell_id_to_str_buf(char *buf, size_t buflen, const struct umts_cell_id *ucid)
+{
+	struct osmo_strbuf sb = { .buf = buf, .len = buflen };
+	OSMO_STRBUF_APPEND_NOLEN(sb, osmo_plmn_name_buf, &ucid->plmn);
+	OSMO_STRBUF_PRINTF(sb, "-L%u-R%u-S%u-C%u", ucid->lac, ucid->rac, ucid->sac, ucid->cid);
+	return sb.chars_needed;
+}
+
+char *umts_cell_id_to_str_c(void *ctx, const struct umts_cell_id *ucid)
+{
+	OSMO_NAME_C_IMPL(ctx, 64, "ERROR", umts_cell_id_to_str_buf, ucid)
+}
+
+const char *umts_cell_id_to_str(const struct umts_cell_id *ucid)
+{
+	return umts_cell_id_to_str_c(OTC_SELECT, ucid);
+}
+
+/* Useful to index a hash table by struct umts_cell_id. */
+uint32_t umts_cell_id_hash(const struct umts_cell_id *ucid)
+{
+	return osmo_jhash(ucid, sizeof(*ucid), 0x423423);
+}
+
+/* parse a string representation of an umts_cell_id into its decoded representation */
+int umts_cell_id_from_str(struct umts_cell_id *ucid, const char *instr)
+{
+	int rc;
+	char buf[4];
+	const char *pos = instr;
+	const char *end;
+
+	/* We want to use struct umts_cell_id as hashtable key. If it ever happens to contain any padding bytes, make
+	 * sure everything is deterministically zero. */
+	memset(ucid, 0, sizeof(*ucid));
+
+	/* read MCC */
+	end = strchr(pos, '-');
+	if (!end || end <= pos || (end - pos) >= sizeof(buf))
+		return -EINVAL;
+	osmo_strlcpy(buf, pos, end - pos + 1);
+	if (osmo_mcc_from_str(buf, &ucid->plmn.mcc))
+		return -EINVAL;
+	pos = end + 1;
+
+	/* read MNC -- here the number of leading zeros matters. */
+	end = strchr(pos, '-');
+	if (!end || end == pos || (end - pos) >= sizeof(buf))
+		return -EINVAL;
+	osmo_strlcpy(buf, pos, end - pos + 1);
+	if (osmo_mnc_from_str(buf, &ucid->plmn.mnc, &ucid->plmn.mnc_3_digits))
+		return -EINVAL;
+	pos = end + 1;
+
+	/* parse the rest, where leading zeros do not matter */
+	rc = sscanf(pos, "L%" SCNu16 "-R%" SCNu8 "-S%" SCNu16 "-C%" SCNu32 "",
+		    &ucid->lac, &ucid->rac, &ucid->sac, &ucid->cid);
+	if (rc < 0)
+		return -errno;
+
+	if (rc != 4)
+		return -EINVAL;
+
+	if (ucid->lac == 0 || ucid->lac == 0xffff)
+		return -EINVAL;
+
+	/* CellIdentity in the ASN.1 syntax is a bit-string of 28 bits length */
+	if (ucid->cid >= (1 << 28))
+		return -EINVAL;
+
+	return 0;
+}

tests/Makefile.am

@@ -1,4 +1,6 @@
 SUBDIRS = \
+	ranap_rab_ass \
+	umts_cell_id \
 	$(NULL)
 
 # The `:;' works around a Bash 3.2 bug when the output is not writeable.
@@ -23,8 +25,13 @@ EXTRA_DIST = \
 	testsuite.at \
 	$(srcdir)/package.m4 \
 	$(TESTSUITE) \
-	ctrl_test_runner.py \
-	osmo-hnbgw.vty \
+	osmo-hnbgw-vty-test.cfg \
+	$(srcdir)/*.vty \
+	$(srcdir)/*.vty.with_pfcp \
+	$(srcdir)/*.ctrl \
+	$(srcdir)/config/*.cfg \
+	$(srcdir)/config/*.vty \
+	$(srcdir)/config/run_tests.sh \
 	$(NULL)
 
 TESTSUITE = $(srcdir)/testsuite
@@ -34,30 +41,56 @@ DISTCLEANFILES = \
 	$(NULL)
 
 if ENABLE_EXT_TESTS
-python-tests: $(BUILT_SOURCES)
-	echo ""
-#	TODO: Enable once we have a VTY/CTRL interface:
-#	$(MAKE) vty-test
-#	osmotestvty.py -p $(abs_top_srcdir) -w $(abs_top_builddir) -v
-#	osmotestconfig.py -p $(abs_top_srcdir) -w $(abs_top_builddir) -v
-#	$(srcdir)/ctrl_test_runner.py -w $(abs_top_builddir) -v
+python-tests:
+	$(MAKE) vty-test
+	osmotestvty.py -p $(abs_top_srcdir) -w $(abs_top_builddir) -v
+	osmotestconfig.py -p $(abs_top_srcdir) -w $(abs_top_builddir) -v
 else
-python-tests: $(BUILT_SOURCES)
+python-tests:
 	echo "Not running python-based tests (determined at configure-time)"
 endif
 
 # Run a specific test with: 'make vty-test VTY_TEST=osmo-hnbgw.vty'
+if ENABLE_PFCP
+VTY_TEST ?= *.vty*
+else
 VTY_TEST ?= *.vty
+endif
 
 # To update the VTY script from current application behavior,
 # pass -u to vty_script_runner.py by doing:
 #   make vty-test U=-u
-vty-test:
+vty-test: $(top_builddir)/src/osmo-hnbgw/osmo-hnbgw
 	osmo_verify_transcript_vty.py -v \
 		-n OsmoHNBGW -p 4261 \
-		-r "$(top_builddir)/src/osmo-hnbgw/osmo-hnbgw -c $(top_srcdir)/doc/examples/osmo-hnbgw/osmo-hnbgw.cfg" \
+		-r "$(top_builddir)/src/osmo-hnbgw/osmo-hnbgw \
+		-c $(srcdir)/osmo-hnbgw-vty-test.cfg" \
 		$(U) $(srcdir)/$(VTY_TEST)
 
+# Test each config/*.cfg file with the corresponding config/*.vty transcript test.
+#
+# To be invoked manually only: This is not part of 'make check' because the
+# output may change when libosmo-sccp changes its VTY appearance, which can
+# cause annoying test fallout.
+#
+# Each config test runs an osmo-hnbgw process to talk to, so they must not run concurrently.
+# To prevent 'make -j N' from running these tests in parallel, call a script with a linear for-loop.
+.PHONY: config-tests
+config-tests:
+	$(srcdir)/config/run_tests.sh "$(top_builddir)/src/osmo-hnbgw/osmo-hnbgw" "$(srcdir)/config/" $U
+
+# Run a specific test with: 'make ctrl-test CTRL_TEST=osmo-hnbgw.ctrl'
+CTRL_TEST ?= *.ctrl
+
+# To update the CTRL script from current application behavior,
+# pass -u to ctrl_script_runner.py by doing:
+#   make ctrl-test U=-u
+ctrl-test: $(top_builddir)/src/osmo-hnbgw/osmo-hnbgw
+	osmo_verify_transcript_ctrl.py -v \
+		-p 4262 \
+		-r "$(top_builddir)/src/osmo-hnbgw/osmo-hnbgw -c $(top_srcdir)/doc/examples/osmo-hnbgw/osmo-hnbgw-cnpool.cfg" \
+		$(U) $(srcdir)/$(CTRL_TEST)
+
 check-local: atconfig $(TESTSUITE)
 	$(SHELL) '$(TESTSUITE)' $(TESTSUITEFLAGS)
 	$(MAKE) $(AM_MAKEFLAGS) python-tests

tests/cnpool.vty

@@ -0,0 +1,432 @@
+OsmoHNBGW> enable
+OsmoHNBGW# list
+...
+  (msc|sgsn) <0-1000> ranap reset
+...
+OsmoHNBGW# msc?
+  msc  Manipulate an IuCS link to an MSC
+OsmoHNBGW# msc ?
+  <0-1000>  MSC/SGSN nr
+OsmoHNBGW# msc 0 ?
+  ranap  Manipulate RANAP layer of Iu-interface
+OsmoHNBGW# msc 0 ranap ?
+  reset  Flip this CN link to disconnected state and re-send RANAP RESET
+
+OsmoHNBGW# sgsn?
+  sgsn  Manipulate an IuPS link to an SGSN
+OsmoHNBGW# sgsn ?
+  <0-1000>  MSC/SGSN nr
+OsmoHNBGW# sgsn 0 ?
+  ranap  Manipulate RANAP layer of Iu-interface
+OsmoHNBGW# sgsn 0 ranap ?
+  reset  Flip this CN link to disconnected state and re-send RANAP RESET
+
+OsmoHNBGW# configure terminal
+
+OsmoHNBGW(config)# ### cnpool doc strings
+OsmoHNBGW(config)# list
+...
+  apply sccp
+...
+
+OsmoHNBGW(config)# apply?
+  apply  Immediately use configuration modified via telnet VTY, and restart components as needed.
+
+OsmoHNBGW(config)# apply ?
+  sccp  For telnet VTY: apply all SCCP and NRI config changes made to any CN pools and CN links in the running osmo-hnbgw process. If 'remote-addr' changed, related SCCP links will be restarted, possibly dropping active UE contexts. This is run implicitly on program startup, only useful to apply changes made later via telnet VTY.
+
+OsmoHNBGW(config)# hnbgw
+OsmoHNBGW(config-hnbgw)# list
+...
+  iucs
+  iups
+...
+OsmoHNBGW(config-hnbgw)# iucs?
+  iucs  Configure IuCS options
+OsmoHNBGW(config-hnbgw)# iups?
+  iups  Configure IuPS options
+
+OsmoHNBGW(config-hnbgw)# iucs
+
+OsmoHNBGW(config-hnbgw-iucs)# list
+...
+  nri bitlen <1-15>
+  nri null add <0-32767> [<0-32767>]
+  nri null del <0-32767> [<0-32767>]
+...
+
+OsmoHNBGW(config-hnbgw-iucs)# nri?
+  nri  Mapping of Network Resource Indicators to this CN peer, for CN pooling
+
+OsmoHNBGW(config-hnbgw-iucs)# nri ?
+  bitlen  Set number of bits that an NRI has, to extract from TMSI identities (always starting just after the TMSI's most significant octet).
+  null    Define NULL-NRI values that cause re-assignment of an MS to a different CN peer, for CN pooling.
+
+OsmoHNBGW(config-hnbgw-iucs)# nri bitlen ?
+  <1-15>  bit count (default: 10)
+
+OsmoHNBGW(config-hnbgw-iucs)# nri null ?
+  add  Add NULL-NRI value (or range)
+  del  Remove NRI value or range from the NRI mapping for this CN link
+
+OsmoHNBGW(config-hnbgw-iucs)# nri null add ?
+  <0-32767>  First value of the NRI value range, should not surpass the configured 'nri bitlen'.
+
+OsmoHNBGW(config-hnbgw-iucs)# nri null add 0 ?
+  [<0-32767>]  Last value of the NRI value range, should not surpass the configured 'nri bitlen' and be larger than the first value; if omitted, apply only the first value.
+
+OsmoHNBGW(config-hnbgw-iucs)# nri null del ?
+  <0-32767>  First value of the NRI value range, should not surpass the configured 'nri bitlen'.
+
+OsmoHNBGW(config-hnbgw-iucs)# nri null del 0 ?
+  [<0-32767>]  Last value of the NRI value range, should not surpass the configured 'nri bitlen' and be larger than the first value; if omitted, apply only the first value.
+
+OsmoHNBGW(config-hnbgw-iucs)# exit
+
+OsmoHNBGW(config-hnbgw)# iups
+
+OsmoHNBGW(config-hnbgw-iups)# list
+...
+  nri bitlen <1-15>
+  nri null add <0-32767> [<0-32767>]
+  nri null del <0-32767> [<0-32767>]
+...
+
+OsmoHNBGW(config-hnbgw-iups)# nri?
+  nri  Mapping of Network Resource Indicators to this CN peer, for CN pooling
+
+OsmoHNBGW(config-hnbgw-iups)# nri ?
+  bitlen  Set number of bits that an NRI has, to extract from TMSI identities (always starting just after the TMSI's most significant octet).
+  null    Define NULL-NRI values that cause re-assignment of an MS to a different CN peer, for CN pooling.
+
+OsmoHNBGW(config-hnbgw-iups)# nri bitlen ?
+  <1-15>  bit count (default: 10)
+
+OsmoHNBGW(config-hnbgw-iups)# nri null ?
+  add  Add NULL-NRI value (or range)
+  del  Remove NRI value or range from the NRI mapping for this CN link
+
+OsmoHNBGW(config-hnbgw-iups)# nri null add ?
+  <0-32767>  First value of the NRI value range, should not surpass the configured 'nri bitlen'.
+
+OsmoHNBGW(config-hnbgw-iups)# nri null add 0 ?
+  [<0-32767>]  Last value of the NRI value range, should not surpass the configured 'nri bitlen' and be larger than the first value; if omitted, apply only the first value.
+
+OsmoHNBGW(config-hnbgw-iups)# nri null del ?
+  <0-32767>  First value of the NRI value range, should not surpass the configured 'nri bitlen'.
+
+OsmoHNBGW(config-hnbgw-iups)# nri null del 0 ?
+  [<0-32767>]  Last value of the NRI value range, should not surpass the configured 'nri bitlen' and be larger than the first value; if omitted, apply only the first value.
+
+OsmoHNBGW(config-hnbgw-iups)# exit
+OsmoHNBGW(config-hnbgw)# exit
+
+OsmoHNBGW(config)# msc?
+  msc  Configure an IuCS link to an MSC
+OsmoHNBGW(config)# msc ?
+  <0-1000>  MSC nr
+
+OsmoHNBGW(config)# sgsn?
+  sgsn  Configure an IuPS link to an SGSN
+OsmoHNBGW(config)# sgsn ?
+  <0-1000>  SGSN nr
+
+OsmoHNBGW(config)# ### The config file has no 'msc' or 'sgsn', so defaults have been set up
+OsmoHNBGW(config)# show running-config
+...
+cs7 instance 0
+ point-code 0.23.5
+...
+ sccp-address addr-dyn-msc-default
+  routing-indicator PC
+  point-code 0.23.1
+  subsystem-number 142
+ sccp-address addr-dyn-sgsn-default
+  routing-indicator PC
+  point-code 0.23.4
+...
+msc 0
+ name msc-0
+ remote-addr addr-dyn-msc-default
+sgsn 0
+ name sgsn-0
+ remote-addr addr-dyn-sgsn-default
+...
+
+OsmoHNBGW(config)# msc 1
+
+OsmoHNBGW(config-msc)# list
+...
+  remote-addr NAME
+  nri add <0-32767> [<0-32767>]
+  nri del <0-32767> [<0-32767>]
+  show nri
+  apply sccp
+  allow-attach
+  no allow-attach
+  allow-emergency
+  no allow-emergency
+...
+
+OsmoHNBGW(config-msc)# remote-addr?
+  remote-addr  SCCP address to send RANAP/SCCP to
+OsmoHNBGW(config-msc)# remote-addr ?
+  NAME  SCCP address book entry name (see 'cs7 instance' / 'sccp-address')
+
+OsmoHNBGW(config-msc)# show nri?
+  nri  Mapping of Network Resource Indicators to this CN peer, for CN pooling
+
+OsmoHNBGW(config-msc)# apply?
+  apply  Immediately use configuration modified via telnet VTY, and restart components as needed.
+
+OsmoHNBGW(config-msc)# apply ?
+  sccp  For telnet VTY: apply SCCP and NRI config changes made to this CN link in the running osmo-hnbgw process. If 'remote-addr' changed, related SCCP links will be restarted, possibly dropping active UE contexts. This is run implicitly on program startup, only useful to apply changes made later via telnet VTY.
+
+OsmoHNBGW(config-msc)# allow-attach?
+  allow-attach  Allow this CN link to attach new subscribers (default).
+
+OsmoHNBGW(config-msc)# allow-emergency?
+  allow-emergency  Allow CM ServiceRequests with type emergency on this CN link
+
+OsmoHNBGW(config-msc)# no ?
+  allow-attach     Do not assign new subscribers to this CN link. Useful if an CN link in an CN link pool is configured to off-load subscribers. The CN link will still be operational for already IMSI-Attached subscribers, but the NAS node selection function will skip this CN link for new subscribers
+  allow-emergency  Do not serve CM ServiceRequests with type emergency on this CN link
+
+OsmoHNBGW(config-msc)# exit
+
+OsmoHNBGW(config)# sgsn 1
+
+OsmoHNBGW(config-sgsn)# list
+...
+  remote-addr NAME
+  nri add <0-32767> [<0-32767>]
+  nri del <0-32767> [<0-32767>]
+  show nri
+  apply sccp
+  allow-attach
+  no allow-attach
+  allow-emergency
+  no allow-emergency
+...
+
+OsmoHNBGW(config-sgsn)# remote-addr?
+  remote-addr  SCCP address to send RANAP/SCCP to
+OsmoHNBGW(config-sgsn)# remote-addr ?
+  NAME  SCCP address book entry name (see 'cs7 instance' / 'sccp-address')
+
+OsmoHNBGW(config-sgsn)# show nri?
+  nri  Mapping of Network Resource Indicators to this CN peer, for CN pooling
+
+OsmoHNBGW(config-sgsn)# apply?
+  apply  Immediately use configuration modified via telnet VTY, and restart components as needed.
+
+OsmoHNBGW(config-sgsn)# apply ?
+  sccp  For telnet VTY: apply SCCP and NRI config changes made to this CN link in the running osmo-hnbgw process. If 'remote-addr' changed, related SCCP links will be restarted, possibly dropping active UE contexts. This is run implicitly on program startup, only useful to apply changes made later via telnet VTY.
+
+OsmoHNBGW(config-sgsn)# allow-attach?
+  allow-attach  Allow this CN link to attach new subscribers (default).
+
+OsmoHNBGW(config-sgsn)# allow-emergency?
+  allow-emergency  Allow CM ServiceRequests with type emergency on this CN link
+
+OsmoHNBGW(config-sgsn)# no ?
+  allow-attach     Do not assign new subscribers to this CN link. Useful if an CN link in an CN link pool is configured to off-load subscribers. The CN link will still be operational for already IMSI-Attached subscribers, but the NAS node selection function will skip this CN link for new subscribers
+  allow-emergency  Do not serve CM ServiceRequests with type emergency on this CN link
+
+OsmoHNBGW(config-sgsn)# exit
+
+OsmoHNBGW(config)# ### Just by entering the nodes above, 'msc 1' and 'sgsn 1' now exist
+OsmoHNBGW(config)# show running-config
+...
+msc 0
+ name msc-0
+ remote-addr addr-dyn-msc-default
+msc 1
+ name msc-1
+sgsn 0
+ name sgsn-0
+ remote-addr addr-dyn-sgsn-default
+sgsn 1
+ name sgsn-1
+...
+
+OsmoHNBGW(config)# ### Add {msc,sgsn}x{2,3}
+
+OsmoHNBGW(config)# msc 2
+OsmoHNBGW(config-msc)# remote-addr addr-msc2
+OsmoHNBGW(config-msc)# no allow-attach
+OsmoHNBGW(config-msc)# exit
+
+OsmoHNBGW(config)# msc 3
+OsmoHNBGW(config-msc)# remote-addr addr-msc3
+OsmoHNBGW(config-msc)# allow-emergency
+OsmoHNBGW(config-msc)# exit
+
+OsmoHNBGW(config)# sgsn 2
+OsmoHNBGW(config-sgsn)# remote-addr addr-sgsn2
+OsmoHNBGW(config-sgsn)# exit
+
+OsmoHNBGW(config)# sgsn 3
+OsmoHNBGW(config-sgsn)# remote-addr addr-sgsn3
+OsmoHNBGW(config-sgsn)# exit
+
+OsmoHNBGW(config)# show running-config
+...
+msc 0
+ name msc-0
+ remote-addr addr-dyn-msc-default
+msc 1
+ name msc-1
+msc 2
+ name msc-2
+ remote-addr addr-msc2
+ no allow-attach
+msc 3
+ name msc-3
+ remote-addr addr-msc3
+ allow-emergency
+sgsn 0
+ name sgsn-0
+ remote-addr addr-dyn-sgsn-default
+sgsn 1
+ name sgsn-1
+sgsn 2
+ name sgsn-2
+ remote-addr addr-sgsn2
+sgsn 3
+ name sgsn-3
+ remote-addr addr-sgsn3
+...
+
+OsmoHNBGW(config)# ### Re-entering existing nodes works (does not create new ones)
+OsmoHNBGW(config)# msc 2
+OsmoHNBGW(config-msc)# allow-attach
+OsmoHNBGW(config-msc)# exit
+OsmoHNBGW(config)# msc 3
+OsmoHNBGW(config-msc)# remote-addr addr-msc4
+OsmoHNBGW(config-msc)# no allow-emergency
+OsmoHNBGW(config-msc)# exit
+OsmoHNBGW(config)# sgsn 2
+OsmoHNBGW(config-sgsn)# remote-addr addr-sgsn4
+OsmoHNBGW(config-sgsn)# exit
+
+OsmoHNBGW(config)# show running-config
+...
+msc 0
+ name msc-0
+ remote-addr addr-dyn-msc-default
+msc 1
+ name msc-1
+msc 2
+ name msc-2
+ remote-addr addr-msc2
+msc 3
+ name msc-3
+ remote-addr addr-msc4
+sgsn 0
+ name sgsn-0
+ remote-addr addr-dyn-sgsn-default
+sgsn 1
+ name sgsn-1
+sgsn 2
+ name sgsn-2
+ remote-addr addr-sgsn4
+sgsn 3
+ name sgsn-3
+ remote-addr addr-sgsn3
+...
+
+OsmoHNBGW(config)# ### Legacy configuration {'iups','iucs'} / 'remote-addr' redirects to {'msc 0','sgsn 0'}:
+
+OsmoHNBGW(config)# hnbgw
+OsmoHNBGW(config-hnbgw)# iucs
+OsmoHNBGW(config-hnbgw-iucs)# remote-addr?
+% There is no matched command.
+OsmoHNBGW(config-hnbgw-iucs)# remote-addr ?
+% There is no matched command.
+OsmoHNBGW(config-hnbgw-iucs)# remote-addr addr-msc0
+% Deprecated: instead of hnbgw/iucs/remote-addr, use 'msc 0'/remote-addr
+OsmoHNBGW(config-hnbgw-iucs)# exit
+
+OsmoHNBGW(config-hnbgw)# iups
+OsmoHNBGW(config-hnbgw-iups)# remote-addr?
+% There is no matched command.
+OsmoHNBGW(config-hnbgw-iups)# remote-addr ?
+% There is no matched command.
+OsmoHNBGW(config-hnbgw-iups)# remote-addr addr-sgsn0
+% Deprecated: instead of hnbgw/iups/remote-addr, use 'sgsn 0'/remote-addr
+OsmoHNBGW(config-hnbgw-iups)# exit
+
+OsmoHNBGW(config-hnbgw)# show running-config
+...
+hnbgw
+...
+msc 0
+ name msc-0
+ remote-addr addr-msc0
+msc 1
+ name msc-1
+msc 2
+ name msc-2
+ remote-addr addr-msc2
+msc 3
+ name msc-3
+ remote-addr addr-msc4
+sgsn 0
+ name sgsn-0
+ remote-addr addr-sgsn0
+sgsn 1
+ name sgsn-1
+sgsn 2
+ name sgsn-2
+ remote-addr addr-sgsn4
+sgsn 3
+ name sgsn-3
+ remote-addr addr-sgsn3
+...
+
+
+OsmoHNBGW(config-hnbgw)# ### placement of the new 'msc' and 'sgsn' nodes must be below 'pfcp' and 'mgw' nodes
+OsmoHNBGW(config-hnbgw)# show running-config
+...
+hnbgw
+... !msc
+ iuh
+... !msc
+ mgw 0
+...
+msc 0
+...
+
+OsmoHNBGW(config-hnbgw)# exit
+OsmoHNBGW(config)# ### Apply all SCCP changes:
+OsmoHNBGW(config)# apply sccp
+OsmoHNBGW(config)# show running-config
+...
+hnbgw
+...
+msc 0
+ name msc-0
+ remote-addr addr-msc0
+msc 1
+ name msc-1
+ remote-addr addr-dyn-msc-default
+msc 2
+ name msc-2
+ remote-addr addr-msc2
+msc 3
+ name msc-3
+ remote-addr addr-msc4
+sgsn 0
+ name sgsn-0
+ remote-addr addr-sgsn0
+sgsn 1
+ name sgsn-1
+ remote-addr addr-dyn-sgsn-default
+sgsn 2
+ name sgsn-2
+ remote-addr addr-sgsn4
+sgsn 3
+ name sgsn-3
+ remote-addr addr-sgsn3
+...

tests/config/defaults.cfg

@@ -0,0 +1 @@
+# configure nothing, to get purely the implicit default config

tests/config/defaults.vty

@@ -0,0 +1,37 @@
+OsmoHNBGW> ### Config file was empty, everything we see here is the default auto configuration
+
+OsmoHNBGW> enable
+
+OsmoHNBGW# show cs7 config
+cs7 instance 0
+ point-code 0.23.5
+ asp asp-clnt-msc-0 2905 0 m3ua
+  local-ip localhost
+  remote-ip localhost
+  role asp
+  sctp-role client
+ as as-clnt-msc-0 m3ua
+  asp asp-clnt-msc-0
+  routing-key 0 0.23.5
+
+OsmoHNBGW# show cnlink
+IuCS: OsmoHNBGW:RI=SSN_PC,PC=0.23.5,SSN=RANAP <-> RI=SSN_PC,PC=0.23.1,SSN=RANAP
+      SS7 route: pc=0=0.0.0 mask=0x0=0.0.0 via AS as-clnt-msc-0 proto=m3ua ASP asp-clnt-msc-0
+      RANAP state: DISCONNECTED
+IuPS: OsmoHNBGW:RI=SSN_PC,PC=0.23.5,SSN=RANAP <-> RI=SSN_PC,PC=0.23.4,SSN=RANAP
+      SS7 route: pc=0=0.0.0 mask=0x0=0.0.0 via AS as-clnt-msc-0 proto=m3ua ASP asp-clnt-msc-0
+      RANAP state: DISCONNECTED
+
+OsmoHNBGW# show running-config
+...
+cs7 instance 0
+ point-code 0.23.5
+hnbgw
+ rnc-id 23
+ log-prefix hnb-id
+ iuh
+ mgw 0
+...
+msc 0
+sgsn 0
+...

tests/config/legacy.cfg

@@ -0,0 +1,12 @@
+# explicitly point at cs7 instance 0 via two address book entries for CS and PS. Leave ASP and AS to auto-configuration.
+cs7 instance 0
+ point-code 1.1.1
+ sccp-address my-msc
+  point-code 1.2.3
+ sccp-address my-sgsn
+  point-code 1.4.2
+hnbgw
+ iucs
+  remote-addr my-msc
+ iups
+  remote-addr my-sgsn

tests/config/legacy.vty

@@ -0,0 +1,50 @@
+OsmoHNBGW> enable
+
+OsmoHNBGW# ### ASP and AS were auto-configured
+OsmoHNBGW# show cs7 config
+cs7 instance 0
+ point-code 1.1.1
+ asp asp-clnt-msc-0 2905 0 m3ua
+  local-ip localhost
+  remote-ip localhost
+  role asp
+  sctp-role client
+ as as-clnt-msc-0 m3ua
+  asp asp-clnt-msc-0
+  routing-key 0 1.1.1
+ sccp-address my-msc
+  routing-indicator PC
+  point-code 1.2.3
+ sccp-address my-sgsn
+  routing-indicator PC
+  point-code 1.4.2
+
+OsmoHNBGW# ### IuCS and IuPS were explicitly pointed to specific remote point-codes, using cs7 instance 0 addresses
+OsmoHNBGW# show cnlink
+IuCS: OsmoHNBGW:RI=SSN_PC,PC=1.1.1,SSN=RANAP <-> my-msc=RI=SSN_PC,PC=1.2.3,SSN=RANAP
+      SS7 route: pc=0=0.0.0 mask=0x0=0.0.0 via AS as-clnt-msc-0 proto=m3ua ASP asp-clnt-msc-0
+      RANAP state: DISCONNECTED
+IuPS: OsmoHNBGW:RI=SSN_PC,PC=1.1.1,SSN=RANAP <-> my-sgsn=RI=SSN_PC,PC=1.4.2,SSN=RANAP
+      SS7 route: pc=0=0.0.0 mask=0x0=0.0.0 via AS as-clnt-msc-0 proto=m3ua ASP asp-clnt-msc-0
+      RANAP state: DISCONNECTED
+
+OsmoHNBGW# show running-config
+...
+cs7 instance 0
+ point-code 1.1.1
+ sccp-address my-msc
+  routing-indicator PC
+  point-code 1.2.3
+ sccp-address my-sgsn
+  routing-indicator PC
+  point-code 1.4.2
+hnbgw
+ rnc-id 23
+ log-prefix hnb-id
+ iuh
+...
+msc 0
+ remote-addr my-msc
+sgsn 0
+ remote-addr my-sgsn
+...

tests/config/one_cs7.cfg

@@ -0,0 +1,3 @@
+# auto-configuration will pick up cs7 instance 0. Configure only the local point-code.
+cs7 instance 0
+ point-code 1.1.1

tests/config/one_cs7.vty

@@ -0,0 +1,31 @@
+OsmoHNBGW> enable
+
+OsmoHNBGW# show cs7 config
+cs7 instance 0
+ point-code 1.1.1
+ asp asp-clnt-msc-0 2905 0 m3ua
+  local-ip localhost
+  remote-ip localhost
+  role asp
+  sctp-role client
+ as as-clnt-msc-0 m3ua
+  asp asp-clnt-msc-0
+  routing-key 0 1.1.1
+
+OsmoHNBGW# show cnlink
+IuCS: OsmoHNBGW:RI=SSN_PC,PC=1.1.1,SSN=RANAP <-> RI=SSN_PC,PC=0.23.1,SSN=RANAP
+      SS7 route: pc=0=0.0.0 mask=0x0=0.0.0 via AS as-clnt-msc-0 proto=m3ua ASP asp-clnt-msc-0
+      RANAP state: DISCONNECTED
+IuPS: OsmoHNBGW:RI=SSN_PC,PC=1.1.1,SSN=RANAP <-> RI=SSN_PC,PC=0.23.4,SSN=RANAP
+      SS7 route: pc=0=0.0.0 mask=0x0=0.0.0 via AS as-clnt-msc-0 proto=m3ua ASP asp-clnt-msc-0
+      RANAP state: DISCONNECTED
+
+OsmoHNBGW# show running-config
+...
+cs7 instance 0
+ point-code 1.1.1
+hnbgw
+...
+msc 0
+sgsn 0
+...

tests/config/one_cs7_with_addrs.cfg

@@ -0,0 +1,11 @@
+# explicitly point at cs7 instance 0 via two address book entries for CS and PS. Leave ASP and AS to auto-configuration.
+cs7 instance 0
+ point-code 1.1.1
+ sccp-address my-msc
+  point-code 1.2.3
+ sccp-address my-sgsn
+  point-code 1.4.2
+msc 0
+ remote-addr my-msc
+sgsn 0
+ remote-addr my-sgsn

tests/config/one_cs7_with_addrs.vty

@@ -0,0 +1,50 @@
+OsmoHNBGW> enable
+
+OsmoHNBGW# ### ASP and AS were auto-configured
+OsmoHNBGW# show cs7 config
+cs7 instance 0
+ point-code 1.1.1
+ asp asp-clnt-msc-0 2905 0 m3ua
+  local-ip localhost
+  remote-ip localhost
+  role asp
+  sctp-role client
+ as as-clnt-msc-0 m3ua
+  asp asp-clnt-msc-0
+  routing-key 0 1.1.1
+ sccp-address my-msc
+  routing-indicator PC
+  point-code 1.2.3
+ sccp-address my-sgsn
+  routing-indicator PC
+  point-code 1.4.2
+
+OsmoHNBGW# ### IuCS and IuPS were explicitly pointed to specific remote point-codes, using cs7 instance 0 addresses
+OsmoHNBGW# show cnlink
+IuCS: OsmoHNBGW:RI=SSN_PC,PC=1.1.1,SSN=RANAP <-> my-msc=RI=SSN_PC,PC=1.2.3,SSN=RANAP
+      SS7 route: pc=0=0.0.0 mask=0x0=0.0.0 via AS as-clnt-msc-0 proto=m3ua ASP asp-clnt-msc-0
+      RANAP state: DISCONNECTED
+IuPS: OsmoHNBGW:RI=SSN_PC,PC=1.1.1,SSN=RANAP <-> my-sgsn=RI=SSN_PC,PC=1.4.2,SSN=RANAP
+      SS7 route: pc=0=0.0.0 mask=0x0=0.0.0 via AS as-clnt-msc-0 proto=m3ua ASP asp-clnt-msc-0
+      RANAP state: DISCONNECTED
+
+OsmoHNBGW# show running-config
+...
+cs7 instance 0
+ point-code 1.1.1
+ sccp-address my-msc
+  routing-indicator PC
+  point-code 1.2.3
+ sccp-address my-sgsn
+  routing-indicator PC
+  point-code 1.4.2
+hnbgw
+ rnc-id 23
+ log-prefix hnb-id
+ iuh
+...
+msc 0
+ remote-addr my-msc
+sgsn 0
+ remote-addr my-sgsn
+...

tests/config/one_cs7_with_iucs_addr.cfg

@@ -0,0 +1,7 @@
+# only set an explicit remote address for IuCS, let IuPS be auto-configured
+cs7 instance 0
+ point-code 1.1.1
+ sccp-address my-msc
+  point-code 1.2.3
+msc 0
+ remote-addr my-msc

tests/config/one_cs7_with_iucs_addr.vty

@@ -0,0 +1,42 @@
+OsmoHNBGW> enable
+
+OsmoHNBGW# show cs7 config
+cs7 instance 0
+ point-code 1.1.1
+ asp asp-clnt-msc-0 2905 0 m3ua
+  local-ip localhost
+  remote-ip localhost
+  role asp
+  sctp-role client
+ as as-clnt-msc-0 m3ua
+  asp asp-clnt-msc-0
+  routing-key 0 1.1.1
+ sccp-address my-msc
+  routing-indicator PC
+  point-code 1.2.3
+
+OsmoHNBGW# ### only IuCS was configured to go to remote-PC = 1.2.3, IuPS auto-configured to remote-PC = 0.23.4
+OsmoHNBGW# show cnlink
+IuCS: OsmoHNBGW:RI=SSN_PC,PC=1.1.1,SSN=RANAP <-> my-msc=RI=SSN_PC,PC=1.2.3,SSN=RANAP
+      SS7 route: pc=0=0.0.0 mask=0x0=0.0.0 via AS as-clnt-msc-0 proto=m3ua ASP asp-clnt-msc-0
+      RANAP state: DISCONNECTED
+IuPS: OsmoHNBGW:RI=SSN_PC,PC=1.1.1,SSN=RANAP <-> RI=SSN_PC,PC=0.23.4,SSN=RANAP
+      SS7 route: pc=0=0.0.0 mask=0x0=0.0.0 via AS as-clnt-msc-0 proto=m3ua ASP asp-clnt-msc-0
+      RANAP state: DISCONNECTED
+
+OsmoHNBGW# show running-config
+...
+cs7 instance 0
+ point-code 1.1.1
+ sccp-address my-msc
+  routing-indicator PC
+  point-code 1.2.3
+hnbgw
+ rnc-id 23
+ log-prefix hnb-id
+ iuh
+...
+msc 0
+ remote-addr my-msc
+sgsn 0
+... !remote-addr

tests/config/one_cs7_with_iups_addr.cfg

@@ -0,0 +1,7 @@
+# only set an explicit remote address for IuPS, let IuCS be auto-configured
+cs7 instance 0
+ point-code 1.1.1
+ sccp-address my-sgsn
+  point-code 1.4.2
+sgsn 0
+ remote-addr my-sgsn

tests/config/one_cs7_with_iups_addr.vty

@@ -0,0 +1,42 @@
+OsmoHNBGW> enable
+
+OsmoHNBGW# show cs7 config
+cs7 instance 0
+ point-code 1.1.1
+ asp asp-clnt-msc-0 2905 0 m3ua
+  local-ip localhost
+  remote-ip localhost
+  role asp
+  sctp-role client
+ as as-clnt-msc-0 m3ua
+  asp asp-clnt-msc-0
+  routing-key 0 1.1.1
+ sccp-address my-sgsn
+  routing-indicator PC
+  point-code 1.4.2
+
+OsmoHNBGW# ### only IuPS was configured to go to remote-PC = 1.4.2, IuCS auto-configured to remote-PC = 0.23.1
+OsmoHNBGW# show cnlink
+IuCS: OsmoHNBGW:RI=SSN_PC,PC=1.1.1,SSN=RANAP <-> RI=SSN_PC,PC=0.23.1,SSN=RANAP
+      SS7 route: pc=0=0.0.0 mask=0x0=0.0.0 via AS as-clnt-msc-0 proto=m3ua ASP asp-clnt-msc-0
+      RANAP state: DISCONNECTED
+IuPS: OsmoHNBGW:RI=SSN_PC,PC=1.1.1,SSN=RANAP <-> my-sgsn=RI=SSN_PC,PC=1.4.2,SSN=RANAP
+      SS7 route: pc=0=0.0.0 mask=0x0=0.0.0 via AS as-clnt-msc-0 proto=m3ua ASP asp-clnt-msc-0
+      RANAP state: DISCONNECTED
+
+OsmoHNBGW# show running-config
+...
+cs7 instance 0
+ point-code 1.1.1
+ sccp-address my-sgsn
+  routing-indicator PC
+  point-code 1.4.2
+hnbgw
+ rnc-id 23
+ log-prefix hnb-id
+ iuh
+...
+msc 0
+sgsn 0
+ remote-addr my-sgsn
+...

tests/config/run_tests.sh

@@ -0,0 +1,21 @@
+#!/bin/sh
+osmo_hnbgw="$1"
+tests_src="$2"
+shift
+shift
+
+if [ ! -x "$osmo_hnbgw" ]; then
+	echo "there seems to be no osmo-hnbgw executable at '$osmo_hnbgw'"
+	exit 1
+fi
+
+if [ ! -d "$tests_src" ]; then
+	echo "there seems to be no tests source dir at '$tests_src'"
+	exit 1
+fi
+
+set -e
+for dot_vty in "$tests_src"/*.vty; do
+	dot_cfg="$(echo $dot_vty | sed 's/\.vty$/.cfg/')"
+	osmo_verify_transcript_vty.py -v -n OsmoHNBGW -p 4261 -r "$osmo_hnbgw -c $dot_cfg" "$dot_vty" $@
+done

tests/config/two_cs7.cfg

@@ -0,0 +1,7 @@
+# there are two cs7 instances, but auto-configuration will only use instance 0.
+
+cs7 instance 0
+ point-code 1.1.1
+
+cs7 instance 1
+ point-code 2.2.2

tests/config/two_cs7.vty

@@ -0,0 +1,37 @@
+OsmoHNBGW> enable
+
+OsmoHNBGW# ### there are two cs7 instances, but auto-configuration has only set up ASP and AS in instance 0.
+OsmoHNBGW# show cs7 config
+cs7 instance 0
+ point-code 1.1.1
+ asp asp-clnt-msc-0 2905 0 m3ua
+  local-ip localhost
+  remote-ip localhost
+  role asp
+  sctp-role client
+ as as-clnt-msc-0 m3ua
+  asp asp-clnt-msc-0
+  routing-key 0 1.1.1
+cs7 instance 1
+ point-code 2.2.2
+
+OsmoHNBGW# ### there are two cs7 instances, but auto-configuration will only use SCCP of instance 0 with local-PC = 1.1.1
+OsmoHNBGW# show cnlink
+IuCS: OsmoHNBGW:RI=SSN_PC,PC=1.1.1,SSN=RANAP <-> RI=SSN_PC,PC=0.23.1,SSN=RANAP
+      SS7 route: pc=0=0.0.0 mask=0x0=0.0.0 via AS as-clnt-msc-0 proto=m3ua ASP asp-clnt-msc-0
+      RANAP state: DISCONNECTED
+IuPS: OsmoHNBGW:RI=SSN_PC,PC=1.1.1,SSN=RANAP <-> RI=SSN_PC,PC=0.23.4,SSN=RANAP
+      SS7 route: pc=0=0.0.0 mask=0x0=0.0.0 via AS as-clnt-msc-0 proto=m3ua ASP asp-clnt-msc-0
+      RANAP state: DISCONNECTED
+
+OsmoHNBGW# show running-config
+...
+cs7 instance 0
+ point-code 1.1.1
+cs7 instance 1
+ point-code 2.2.2
+hnbgw
+...
+msc 0
+sgsn 0
+...

tests/config/two_cs7_with_addrs.cfg

@@ -0,0 +1,16 @@
+# two cs7 instances, both will be auto-configured for ASP and AS because address book entries point at both.
+
+cs7 instance 0
+ point-code 1.1.1
+ sccp-address my-msc
+  point-code 1.2.3
+
+cs7 instance 1
+ point-code 2.2.2
+ sccp-address my-sgsn
+  point-code 2.4.2
+
+msc 0
+ remote-addr my-msc
+sgsn 0
+ remote-addr my-sgsn

tests/config/two_cs7_with_addrs.vty

@@ -0,0 +1,62 @@
+OsmoHNBGW> enable
+
+OsmoHNBGW# ### two cs7 instances, both have been auto-configured for ASP and AS because address book entries point at both.
+OsmoHNBGW# show cs7 config
+cs7 instance 0
+ point-code 1.1.1
+ asp asp-clnt-msc-0 2905 0 m3ua
+  local-ip localhost
+  remote-ip localhost
+  role asp
+  sctp-role client
+ as as-clnt-msc-0 m3ua
+  asp asp-clnt-msc-0
+  routing-key 0 1.1.1
+ sccp-address my-msc
+  routing-indicator PC
+  point-code 1.2.3
+cs7 instance 1
+ point-code 2.2.2
+ asp asp-clnt-sgsn-0 2905 0 m3ua
+  local-ip localhost
+  remote-ip localhost
+  role asp
+  sctp-role client
+ as as-clnt-sgsn-0 m3ua
+  asp asp-clnt-sgsn-0
+  routing-key 0 2.2.2
+ sccp-address my-sgsn
+  routing-indicator PC
+  point-code 2.4.2
+
+OsmoHNBGW# ### IuCS on instance 0 with local-PC = 1.1.1, IuPS on instance 1 with local-PC = 2.2.2
+OsmoHNBGW# show cnlink
+IuCS: OsmoHNBGW:RI=SSN_PC,PC=1.1.1,SSN=RANAP <-> my-msc=RI=SSN_PC,PC=1.2.3,SSN=RANAP
+      SS7 route: pc=0=0.0.0 mask=0x0=0.0.0 via AS as-clnt-msc-0 proto=m3ua ASP asp-clnt-msc-0
+      RANAP state: DISCONNECTED
+IuPS: OsmoHNBGW:RI=SSN_PC,PC=2.2.2,SSN=RANAP <-> my-sgsn=RI=SSN_PC,PC=2.4.2,SSN=RANAP
+      SS7 route: pc=0=0.0.0 mask=0x0=0.0.0 via AS as-clnt-sgsn-0 proto=m3ua ASP asp-clnt-sgsn-0
+      RANAP state: DISCONNECTED
+
+OsmoHNBGW# show running-config
+...
+cs7 instance 0
+ point-code 1.1.1
+ sccp-address my-msc
+  routing-indicator PC
+  point-code 1.2.3
+cs7 instance 1
+ point-code 2.2.2
+ sccp-address my-sgsn
+  routing-indicator PC
+  point-code 2.4.2
+hnbgw
+ rnc-id 23
+ log-prefix hnb-id
+ iuh
+...
+msc 0
+ remote-addr my-msc
+sgsn 0
+ remote-addr my-sgsn
+...

tests/ctrl_test_runner.py

@@ -1,207 +0,0 @@
-#!/usr/bin/env python3
-
-# (C) 2013 by Jacob Erlbeck <jerlbeck@sysmocom.de>
-# (C) 2014 by Holger Hans Peter Freyther
-# based on vty_test_runner.py:
-# (C) 2013 by Katerina Barone-Adesi <kat.obsc@gmail.com>
-# (C) 2013 by Holger Hans Peter Freyther
-# based on bsc_control.py.
-
-# This program is free software: you can redistribute it and/or modify
-# it under the terms of the GNU General Public License as published by
-# the Free Software Foundation, either version 3 of the License, or
-# (at your option) any later version.
-
-# This program is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-# GNU General Public License for more details.
-
-# You should have received a copy of the GNU General Public License
-# along with this program.  If not, see <http://www.gnu.org/licenses/>.
-
-import os
-import time
-import unittest
-import socket
-import sys
-import struct
-
-import osmopy.obscvty as obscvty
-import osmopy.osmoutil as osmoutil
-from osmopy.osmo_ipa import Ctrl, IPA
-
-# to be able to find $top_srcdir/doc/...
-confpath = os.path.join(sys.path[0], '..')
-verbose = False
-
-class TestCtrlBase(unittest.TestCase):
-
-    def ctrl_command(self):
-        raise Exception("Needs to be implemented by a subclass")
-
-    def ctrl_app(self):
-        raise Exception("Needs to be implemented by a subclass")
-
-    def setUp(self):
-        osmo_ctrl_cmd = self.ctrl_command()[:]
-        config_index = osmo_ctrl_cmd.index('-c')
-        if config_index:
-            cfi = config_index + 1
-            osmo_ctrl_cmd[cfi] = os.path.join(confpath, osmo_ctrl_cmd[cfi])
-
-        try:
-            self.proc = osmoutil.popen_devnull(osmo_ctrl_cmd)
-        except OSError:
-            print("Current directory: %s" % os.getcwd(), file=sys.stderr)
-            print("Consider setting -b", file=sys.stderr)
-
-        appstring = self.ctrl_app()[2]
-        appport = self.ctrl_app()[0]
-        self.connect("127.0.0.1", appport)
-        self.next_id = 1000
-
-    def tearDown(self):
-        self.disconnect()
-        osmoutil.end_proc(self.proc)
-
-    def disconnect(self):
-        if not (self.sock is None):
-            self.sock.close()
-
-    def connect(self, host, port):
-        if verbose:
-            print("Connecting to host %s:%i" % (host, port))
-
-        retries = 30
-        while True:
-            try:
-                sck = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
-                sck.setblocking(1)
-                sck.connect((host, port))
-            except IOError:
-                retries -= 1
-                if retries <= 0:
-                    raise
-                time.sleep(.1)
-                continue
-            break
-        self.sock = sck
-        return sck
-
-    def send(self, data):
-        if verbose:
-            print("Sending \"%s\"" %(data))
-        data = Ctrl().add_header(data)
-        return self.sock.send(data) == len(data)
-
-    def send_set(self, var, value, id):
-        setmsg = "SET %s %s %s" %(id, var, value)
-        return self.send(setmsg)
-
-    def send_get(self, var, id):
-        getmsg = "GET %s %s" %(id, var)
-        return self.send(getmsg)
-
-    def do_set(self, var, value):
-        id = self.next_id
-        self.next_id += 1
-        self.send_set(var, value, id)
-        return self.recv_msgs()[id]
-
-    def do_get(self, var):
-        id = self.next_id
-        self.next_id += 1
-        self.send_get(var, id)
-        return self.recv_msgs()[id]
-
-    def recv_msgs(self):
-        responses = {}
-        data = self.sock.recv(4096)
-        while (len(data)>0):
-            (head, data) = IPA().split_combined(data)
-            answer = Ctrl().rem_header(head).decode()
-            if verbose:
-                print("Got message:", answer)
-            (mtype, id, msg) = answer.split(None, 2)
-            id = int(id)
-            rsp = {'mtype': mtype, 'id': id}
-            if mtype == "ERROR":
-                rsp['error'] = msg
-            else:
-                split = msg.split(None, 1)
-                rsp['var'] = split[0]
-                if len(split) > 1:
-                    rsp['value'] = split[1]
-                else:
-                    rsp['value'] = None
-            responses[id] = rsp
-
-        if verbose:
-            print("Decoded replies: ", responses)
-
-        return responses
-
-
-class TestCtrlHNB(TestCtrlBase):
-
-    def tearDown(self):
-        TestCtrlBase.tearDown(self)
-        os.unlink("tmp_dummy_sock")
-
-    def ctrl_command(self):
-        return ["./src/osmo-hnbgw/osmo-hnbgw", "-r", "tmp_dummy_sock", "-c",
-                "doc/examples/osmo-hnbgw/osmo-hnbgw.cfg"]
-
-    def ctrl_app(self):
-        return (4249, "./src/osmo-hnbgw/osmo-hnbgw", "OsmoHNBGW", "hnb")
-
-    def testCtrlErrs(self):
-        r = self.do_get('invalid')
-        self.assertEqual(r['mtype'], 'ERROR')
-        self.assertEqual(r['error'], 'Command not found')
-
-        r = self.do_get('hnbgw.999')
-        self.assertEqual(r['mtype'], 'ERROR')
-        self.assertEqual(r['error'], 'Error while resolving object')
-
-def add_hnbgw_test(suite, workdir, klass):
-    if not os.path.isfile(os.path.join(workdir, "src/osmo-hnbgw/osmo-hnbgw")):
-        print("Skipping the HNBGW test")
-        return
-    test = unittest.TestLoader().loadTestsFromTestCase(klass)
-    suite.addTest(test)
-
-if __name__ == '__main__':
-    import argparse
-    import sys
-
-    workdir = '.'
-
-    parser = argparse.ArgumentParser()
-    parser.add_argument("-v", "--verbose", dest="verbose",
-                        action="store_true", help="verbose mode")
-    parser.add_argument("-p", "--pythonconfpath", dest="p",
-                        help="searchpath for config")
-    parser.add_argument("-w", "--workdir", dest="w",
-                        help="Working directory")
-    args = parser.parse_args()
-
-    verbose_level = 1
-    if args.verbose:
-        verbose_level = 2
-        verbose = True
-
-    if args.w:
-        workdir = args.w
-
-    if args.p:
-        confpath = args.p
-
-    print("confpath %s, workdir %s" % (confpath, workdir))
-    os.chdir(workdir)
-    print("Running tests for specific control commands")
-    suite = unittest.TestSuite()
-    add_hnbgw_test(suite, workdir, TestCtrlHNB)
-    res = unittest.TextTestRunner(verbosity=verbose_level).run(suite)
-    sys.exit(len(res.errors) + len(res.failures))

tests/nri_cfg.vty

@@ -0,0 +1,279 @@
+OsmoHNBGW> show nri
+hnbgw
+ iucs
+  nri bitlen 10
+  % No NULL-NRI entries
+ iups
+  nri bitlen 10
+  % No NULL-NRI entries
+msc 0
+ % no NRI mappings
+sgsn 0
+ % no NRI mappings
+
+OsmoHNBGW> enable
+OsmoHNBGW# configure terminal
+
+OsmoHNBGW(config)# msc 0
+
+OsmoHNBGW(config-msc)# list
+...
+  nri add <0-32767> [<0-32767>]
+  nri del <0-32767> [<0-32767>]
+  show nri
+...
+OsmoHNBGW(config-msc)# nri ?
+  add  Add NRI value or range to the NRI mapping for this CN link
+  del  Remove NRI value or range from the NRI mapping for this CN link
+OsmoHNBGW(config-msc)# nri add ?
+  <0-32767>  First value of the NRI value range, should not surpass the configured 'nri bitlen'.
+OsmoHNBGW(config-msc)# nri add 23 ?
+  [<0-32767>]  Last value of the NRI value range, should not surpass the configured 'nri bitlen' and be larger than the first value; if omitted, apply only the first value.
+
+OsmoHNBGW(config-msc)# nri add 23
+OsmoHNBGW(config-msc)# nri add 256 511
+OsmoHNBGW(config-msc)# nri add 100 200
+OsmoHNBGW(config-msc)# nri add 1024 1024
+% Warning: msc 0: Warning: NRI range surpasses current NRI bitlen: 1024..1024
+OsmoHNBGW(config-msc)# show nri
+msc 0
+ nri add 23
+ nri add 100 200
+ nri add 256 511
+ nri add 1024
+OsmoHNBGW(config-msc)# exit
+
+OsmoHNBGW(config)# ### Do msc 2 first, to see that the order of mscs in the internal list is not determined by the msc->nr,
+OsmoHNBGW(config)# ### and whichever was configured first gets higher priority for overlaps.
+
+OsmoHNBGW(config)# msc 2
+OsmoHNBGW(config-msc)# nri add 200 300
+% Warning: msc 2: NRI range [200..300] overlaps between msc 2 and msc 0. For overlaps, msc 0 has higher priority than msc 2
+OsmoHNBGW(config-msc)# nri add 1024 1025
+% Warning: msc 2: Warning: NRI range surpasses current NRI bitlen: 1024..1025
+% Warning: msc 2: NRI range [1024..1025] overlaps between msc 2 and msc 0. For overlaps, msc 0 has higher priority than msc 2
+OsmoHNBGW(config-msc)# exit
+
+OsmoHNBGW(config)# msc 1
+OsmoHNBGW(config-msc)# nri add 42
+OsmoHNBGW(config-msc)# nri add 512 767
+OsmoHNBGW(config-msc)# nri add 200 300
+% Warning: msc 1: NRI range [200..300] overlaps between msc 1 and msc 0. For overlaps, msc 0 has higher priority than msc 1
+% Warning: msc 1: NRI range [200..300] overlaps between msc 1 and msc 2. For overlaps, msc 2 has higher priority than msc 1
+OsmoHNBGW(config-msc)# nri add 1024 1025
+% Warning: msc 1: Warning: NRI range surpasses current NRI bitlen: 1024..1025
+% Warning: msc 1: NRI range [1024..1025] overlaps between msc 1 and msc 0. For overlaps, msc 0 has higher priority than msc 1
+% Warning: msc 1: NRI range [1024..1025] overlaps between msc 1 and msc 2. For overlaps, msc 2 has higher priority than msc 1
+OsmoHNBGW(config-msc)# show nri
+msc 1
+ nri add 42
+ nri add 200 300
+ nri add 512 767
+ nri add 1024 1025
+OsmoHNBGW(config-msc)# exit
+
+OsmoHNBGW(config)# do show nri
+hnbgw
+ iucs
+  nri bitlen 10
+  % No NULL-NRI entries
+ iups
+  nri bitlen 10
+  % No NULL-NRI entries
+msc 0
+ nri add 23
+ nri add 100 200
+ nri add 256 511
+ nri add 1024
+msc 2
+ nri add 200 300
+ nri add 1024 1025
+msc 1
+ nri add 42
+ nri add 200 300
+ nri add 512 767
+ nri add 1024 1025
+sgsn 0
+ % no NRI mappings
+
+OsmoHNBGW(config)# ### msc and sgsn have separate scopes of NRI, i.e. overlaps are no problem
+OsmoHNBGW(config)# sgsn 0
+OsmoHNBGW(config-sgsn)# nri add 0 1023
+OsmoHNBGW(config-sgsn)# show nri
+sgsn 0
+ nri add 0 1023
+OsmoHNBGW(config-sgsn)# exit
+
+OsmoHNBGW(config)# ### NULL-NRI config
+OsmoHNBGW(config)# hnbgw
+OsmoHNBGW(config-hnbgw)# iucs
+
+OsmoHNBGW(config-hnbgw-iucs)# list
+...
+  nri bitlen <1-15>
+  nri null add <0-32767> [<0-32767>]
+  nri null del <0-32767> [<0-32767>]
+...
+
+OsmoHNBGW(config-hnbgw-iucs)# nri ?
+  bitlen  Set number of bits that an NRI has, to extract from TMSI identities (always starting just after the TMSI's most significant octet).
+  null    Define NULL-NRI values that cause re-assignment of an MS to a different CN peer, for CN pooling.
+
+OsmoHNBGW(config-hnbgw-iucs)# nri bitlen ?
+  <1-15>  bit count (default: 10)
+
+OsmoHNBGW(config-hnbgw-iucs)# nri bitlen 11
+OsmoHNBGW(config-hnbgw-iucs)# show running-config
+...
+hnbgw
+...
+ iucs
+...
+  nri bitlen 11
+...
+
+OsmoHNBGW(config-hnbgw-iucs)# nri null ?
+  add  Add NULL-NRI value (or range)
+  del  Remove NRI value or range from the NRI mapping for this CN link
+
+OsmoHNBGW(config-hnbgw-iucs)# nri null add ?
+  <0-32767>  First value of the NRI value range, should not surpass the configured 'nri bitlen'.
+OsmoHNBGW(config-hnbgw-iucs)# nri null add 0 ?
+  [<0-32767>]  Last value of the NRI value range, should not surpass the configured 'nri bitlen' and be larger than the first value; if omitted, apply only the first value.
+
+OsmoHNBGW(config-hnbgw-iucs)# nri null del ?
+  <0-32767>  First value of the NRI value range, should not surpass the configured 'nri bitlen'.
+OsmoHNBGW(config-hnbgw-iucs)# nri null del 0 ?
+  [<0-32767>]  Last value of the NRI value range, should not surpass the configured 'nri bitlen' and be larger than the first value; if omitted, apply only the first value.
+
+OsmoHNBGW(config-hnbgw-iucs)# exit
+
+OsmoHNBGW(config-hnbgw)# iups
+
+OsmoHNBGW(config-hnbgw-iups)# list
+...
+  nri bitlen <1-15>
+  nri null add <0-32767> [<0-32767>]
+  nri null del <0-32767> [<0-32767>]
+...
+
+OsmoHNBGW(config-hnbgw-iups)# nri ?
+  bitlen  Set number of bits that an NRI has, to extract from TMSI identities (always starting just after the TMSI's most significant octet).
+  null    Define NULL-NRI values that cause re-assignment of an MS to a different CN peer, for CN pooling.
+
+OsmoHNBGW(config-hnbgw-iups)# nri bitlen ?
+  <1-15>  bit count (default: 10)
+
+OsmoHNBGW(config-hnbgw-iups)# nri bitlen 9
+OsmoHNBGW(config-hnbgw-iups)# show running-config
+...
+hnbgw
+...
+ iups
+...
+  nri bitlen 9
+...
+
+OsmoHNBGW(config-hnbgw-iups)# nri null ?
+  add  Add NULL-NRI value (or range)
+  del  Remove NRI value or range from the NRI mapping for this CN link
+
+OsmoHNBGW(config-hnbgw-iups)# nri null add ?
+  <0-32767>  First value of the NRI value range, should not surpass the configured 'nri bitlen'.
+OsmoHNBGW(config-hnbgw-iups)# nri null add 0 ?
+  [<0-32767>]  Last value of the NRI value range, should not surpass the configured 'nri bitlen' and be larger than the first value; if omitted, apply only the first value.
+
+OsmoHNBGW(config-hnbgw-iups)# nri null del ?
+  <0-32767>  First value of the NRI value range, should not surpass the configured 'nri bitlen'.
+OsmoHNBGW(config-hnbgw-iups)# nri null del 0 ?
+  [<0-32767>]  Last value of the NRI value range, should not surpass the configured 'nri bitlen' and be larger than the first value; if omitted, apply only the first value.
+
+OsmoHNBGW(config-hnbgw-iups)# exit
+
+OsmoHNBGW(config-hnbgw)# exit
+
+OsmoHNBGW(config)# msc 0
+OsmoHNBGW(config-msc)# nri del 0 10000
+OsmoHNBGW(config-msc)# exit
+OsmoHNBGW(config)# msc 1
+OsmoHNBGW(config-msc)# nri del 0 10000
+OsmoHNBGW(config-msc)# exit
+OsmoHNBGW(config)# msc 2
+OsmoHNBGW(config-msc)# nri del 0 10000
+OsmoHNBGW(config-msc)# exit
+OsmoHNBGW(config)# do show nri
+hnbgw
+ iucs
+  nri bitlen 11
+  % No NULL-NRI entries
+ iups
+  nri bitlen 9
+  % No NULL-NRI entries
+msc 0
+ % no NRI mappings
+msc 2
+ % no NRI mappings
+msc 1
+ % no NRI mappings
+sgsn 0
+ nri add 0 1023
+
+OsmoHNBGW(config)# msc 0
+OsmoHNBGW(config-msc)# nri add 0 1000
+OsmoHNBGW(config-msc)# show nri
+msc 0
+ nri add 0 1000
+OsmoHNBGW(config-msc)# nri del 23
+OsmoHNBGW(config-msc)# nri del 200 300
+OsmoHNBGW(config-msc)# nri del 1000 2000
+OsmoHNBGW(config-msc)# show nri
+msc 0
+ nri add 0 22
+ nri add 24 199
+ nri add 301 999
+OsmoHNBGW(config-msc)# nri add 23
+OsmoHNBGW(config-msc)# show nri
+msc 0
+ nri add 0 199
+ nri add 301 999
+OsmoHNBGW(config-msc)# nri add 200 300
+OsmoHNBGW(config-msc)# show nri
+msc 0
+ nri add 0 999
+OsmoHNBGW(config-msc)# nri add 1000
+OsmoHNBGW(config-msc)# show nri
+msc 0
+ nri add 0 1000
+
+OsmoHNBGW(config-msc)# show running-config
+... ! no allow-attach
+OsmoHNBGW(config-msc)# no allow-attach
+OsmoHNBGW(config-msc)# show running-config
+...
+msc 0
+...
+ nri add 0 1000
+ no allow-attach
+... ! no allow-attach
+OsmoHNBGW(config-msc)# exit
+OsmoHNBGW(config)# sgsn 1
+OsmoHNBGW(config-sgsn)# no allow-attach
+OsmoHNBGW(config-sgsn)# show running-config
+...
+msc 0
+...
+ nri add 0 1000
+ no allow-attach
+... ! no allow-attach
+sgsn 1
+...
+ no allow-attach
+...
+
+OsmoHNBGW(config-sgsn)# allow-attach
+OsmoHNBGW(config-sgsn)# exit
+OsmoHNBGW(config)# msc 0
+OsmoHNBGW(config-msc)# allow-attach
+OsmoHNBGW(config-msc)# show running-config
+... ! no allow-attach
+OsmoHNBGW(config-msc)# exit

tests/osmo-hnbgw-vty-test.cfg

@@ -0,0 +1,39 @@
+log stderr
+ logging filter all 1
+ logging color 1
+ logging print level 1
+ logging print category 1
+ logging print category-hex 0
+ logging print file basename last
+ logging print extended-timestamp 1
+ logging level set-all notice
+
+# Define some cs7 address book entries to play with
+cs7 instance 0
+ sccp-address addr-msc0
+  point-code 0.1.0
+ sccp-address addr-msc2
+  point-code 0.1.2
+ sccp-address addr-sgsn3
+  point-code 0.2.3
+ sccp-address addr-sgsn4
+  point-code 0.2.4
+
+cs7 instance 1
+ sccp-address addr-sgsn0
+  point-code 1.2.0
+ sccp-address addr-sgsn2
+  point-code 1.2.2
+ sccp-address addr-msc3
+  point-code 1.1.3
+ sccp-address addr-msc4
+  point-code 1.1.4
+
+hnbgw
+ iuh
+  local-ip 0.0.0.0
+ mgw 0
+  remote-ip 127.0.0.1
+  local-port 2729
+  remote-port 2427
+  reset-endpoint rtpbridge/*