mgcp-client: MGCP response: pass fmtp to caller

When receiving MGCP responses, so far libosmo-mgcp-client completely
ignored a=fmtp: parameters (like 'octet-align'). Add fmtp parsing to
pass the fmtp string to the caller as-is.

Since the responses so far never included the octet_aligned flags, do
not bother to parse fmtp to populate the legacy items. New callers
should use the fmtp string.

Change-Id: If8ca5c3880cad9e41b80e9d1c821439b0d7b7e23

Makefile.am

@@ -24,6 +24,7 @@ pkgconfig_DATA = \
 BUILT_SOURCES = $(top_srcdir)/.version
 EXTRA_DIST = \
 	     .version \
+	     README.md \
 	     contrib/osmo-mgw.spec.in \
 	     debian \
 	     git-version-gen \

README

@@ -1,24 +0,0 @@
-About OsmoMGW
-=============
-
-OsmoMGW originated from the OpenBSC project, which started as a minimalistic
-all-in-one implementation of the GSM Network. In 2017, OpenBSC had reached
-maturity and diversity (including M3UA SIGTRAN and 3G support in the form of
-IuCS and IuPS interfaces) that naturally lead to a separation of the all-in-one
-approach to fully independent separate programs as in typical GSM networks.
-
-OsmoMGW was one of the parts split off from the old openbsc.git. It originated
-as a solution to merely navigate RTP streams through a NAT, but has since
-matured to a Media Gateway implementation that is capable of streaming RTP for
-2G (AoIP) and 3G (IuCS) GSM networks as well as (still not implemented at time
-of writing) transcoding between TRAU, various RTP payloads and IuUP.
-
-The OsmoMGW program exposes an MGCP interface towards clients like OsmoMSC and
-OsmoBSC, and receives and sends RTP streams as configured via MGCP.
-
-The libosmo-mgcp-client library exposes utilities used by e.g. OsmoMSC (found
-in osmo-msc.git) to instruct OsmoMGW via its MGCP service.
-
-Find OsmoMGW issue tracker and wiki online at
-https://osmocom.org/projects/osmo-mgw
-https://osmocom.org/projects/osmo-mgw/wiki

README.md

@@ -0,0 +1,102 @@
+osmo-mgw - Osmocom MGW (Media GateWay) Implementation
+=====================================================
+
+This repository contains a C-language implementation of an MGW (Media
+GateWay) for use [not only] within the 2G (GSM) and/or 3G (UMTS)
+Cellular Network built using Osmocom CNI (Cellular Network
+Infrastructure) software.
+
+The OsmoMGW program provides an MGCP interface towards an MGCP call agent
+(client) like OsmoMSC and OsmoBSC, and receives and sends RTP streams as
+configured via the MGCP control plane.
+
+This Media Gateway implementation is capable of
+
+* streaming RTP for 2G (3GPP AoIP and Abis-over-IP)
+* streaming RTP for 3G (IuCS including the IuFP protocol)
+* TDM (E1/T1) based Abis interface with TRAU frames on 16k sub-slots
+* basic support for LCLS (Local Call, Local Switch) related features
+* various built-in translation capabilities
+  * between Abis TRAU frames and RTP formats
+  * between 2G AMR/RTP and 3G AMR/IuFP/RTP
+  * between bandwidth-efficient and octet-aligned AMR
+  * between different standards for encapsulating GSM HR codec frames in RTP
+
+osmo-mgw is typically co-located with
+
+ * osmo-bsc (GSM BSC)
+ * osmo-msc (GSM/UMTS MSC)
+ * osmo-hnbgw (UMTS HNBGW); osmo-mgw implements RTP relay between Iuh
+   and IuCS interfaces
+
+The libosmo-mgcp-client library exposes utilities used by e.g. OsmoMSC
+(found in osmo-msc.git) to instruct OsmoMGW via its MGCP service.
+
+Homepage
+--------
+
+You can find the OsmoMGW issue tracker and wiki online at
+<https://osmocom.org/projects/osmo-mgw> and <https://osmocom.org/projects/osmo-mgw/wiki>.
+
+
+GIT Repository
+--------------
+
+You can clone from the official osmo-mgw.git repository using
+
+        git clone https://gitea.osmocom.org/cellular-infrastructure/osmo-mgw
+
+There is a web interface at <https://gitea.osmocom.org/cellular-infrastructure/osmo-mgw>
+
+
+Documentation
+-------------
+
+User Manuals and VTY reference manuals are [optionally] built in PDF form
+as part of the build process.
+
+Pre-rendered PDF version of the current "master" can be found at
+[User Manual](https://ftp.osmocom.org/docs/latest/osmomgw-usermanual.pdf)
+as well as the [VTY Reference Manual](https://ftp.osmocom.org/docs/latest/osmomgw-vty-reference.pdf)
+
+
+Mailing List
+------------
+
+Discussions related to osmo-mgw are happening on the
+openbsc@lists.osmocom.org mailing list, please see
+<https://lists.osmocom.org/mailman/listinfo/openbsc> for subscription
+options and the list archive.
+
+Please observe the [Osmocom Mailing List
+Rules](https://osmocom.org/projects/cellular-infrastructure/wiki/Mailing_List_Rules)
+when posting.
+
+
+Contributing
+------------
+
+Our coding standards are described at
+<https://osmocom.org/projects/cellular-infrastructure/wiki/Coding_standards>
+
+We use a gerrit based patch submission/review process for managing
+contributions.  Please see
+<https://osmocom.org/projects/cellular-infrastructure/wiki/Gerrit> for
+more details
+
+The current patch queue for osmo-mgw can be seen at
+<https://gerrit.osmocom.org/#/q/project:osmo-mgw+status:open>
+
+
+History
+-------
+
+OsmoMGW originated from the OpenBSC project, which started as a minimalistic
+all-in-one implementation of the GSM Network. In 2017, OpenBSC had reached
+maturity and diversity (including M3UA SIGTRAN and 3G support in the form of
+IuCS and IuPS interfaces) that naturally lead to a separation of the all-in-one
+approach to fully independent separate programs as in typical GSM networks.
+
+OsmoMGW was one of the parts split off from the old openbsc.git. It originated
+as a solution to merely navigate RTP streams through a NAT, but has since
+matured.

TODO-RELEASE

@@ -24,6 +24,18 @@
 # If any interfaces have been removed or changed since the last public release, a=0.
 #
 #library		what		description / commit summary line
-libosmo-netif           >1.2.0          OSMUX_DEFAULT_PORT, osmux_xfrm_output_*, osmux_xfrm_input_*
-libosmocore             >1.7.0          osmo_sockaddr_is_any()
-libmgcp-client          NEW APIs        mgcp_client_pool_member_...(), mgcp_client_pool_config_write()
+libosmo-mgcp-client	remove public API	These public API items have not been called by any of our osmo-programs
+						for many years. Any sane caller of libosmo-mgcp-client should use the
+						higher level osmo_mgcpc_* API instead. Move these to a private header:
+						struct mgcp_response_head
+						struct mgcp_response
+						struct mgcp_msg
+						mgcp_response_parse_params()
+						mgcp_client_tx()
+						mgcp_client_cancel()
+						mgcp_msg_gen()
+						mgcp_msg_trans_id()
+libosmo-mgcp-client	deprecate public API	New code should no longer use codecs[], instead use ptmap[].codec. There
+						is backwards compat code that moves codecs[] entries, if any, over to
+						ptmap[], so callers may migrate at own leisure.
+osmo-mgw		remove cfg		Remove VTY config item 'sdp audio fmtp-extra' (see OS#6313)

configure.ac

@@ -44,15 +44,16 @@ AC_SEARCH_LIBS([dlsym], [dl dld], [LIBRARY_DLSYM="$LIBS";LIBS=""])
 AC_SUBST(LIBRARY_DLSYM)
 
 
-PKG_CHECK_MODULES(LIBOSMOCORE, libosmocore >= 1.7.0)
-PKG_CHECK_MODULES(LIBOSMOGSM, libosmogsm >= 1.7.0)
-PKG_CHECK_MODULES(LIBOSMOCTRL, libosmoctrl >= 1.7.0)
-PKG_CHECK_MODULES(LIBOSMOVTY, libosmovty >= 1.7.0)
-PKG_CHECK_MODULES(LIBOSMONETIF, libosmo-netif >= 1.2.0)
-PKG_CHECK_MODULES(LIBOSMOABIS, libosmoabis >= 1.3.0)
-PKG_CHECK_MODULES(LIBOSMOTRAU, libosmotrau >= 1.3.0)
+PKG_CHECK_MODULES(LIBOSMOCORE, libosmocore >= 1.9.0)
+PKG_CHECK_MODULES(LIBOSMOGSM, libosmogsm >= 1.9.0)
+PKG_CHECK_MODULES(LIBOSMOCTRL, libosmoctrl >= 1.9.0)
+PKG_CHECK_MODULES(LIBOSMOVTY, libosmovty >= 1.9.0)
+PKG_CHECK_MODULES(LIBOSMONETIF, libosmo-netif >= 1.4.0)
+PKG_CHECK_MODULES(LIBOSMOABIS, libosmoabis >= 1.5.0)
+PKG_CHECK_MODULES(LIBOSMOTRAU, libosmotrau >= 1.5.0)
 
-CFLAGS="$CFLAGS -pthread"
+CFLAGS="$CFLAGS -DBUILDING_LIBOSMOMGCPCLIENT -pthread"
+CPPFLAGS="$CPPFLAGS -DBUILDING_LIBOSMOMGCPCLIENT -pthread"
 LDFLAGS="$LDFLAGS -pthread"
 
 AC_ARG_ENABLE(sanitize,
@@ -79,6 +80,7 @@ AC_ARG_ENABLE(werror,
 if test x"$werror" = x"yes"
 then
 	WERROR_FLAGS="-Werror"
+	WERROR_FLAGS+=" -Werror=implicit-int -Werror=int-conversion -Werror=old-style-definition"
 	WERROR_FLAGS+=" -Wno-error=deprecated -Wno-error=deprecated-declarations"
 	WERROR_FLAGS+=" -Wno-error=cpp" # "#warning"
 	CFLAGS="$CFLAGS $WERROR_FLAGS"
@@ -187,9 +189,11 @@ AC_OUTPUT(
     libosmo-mgcp-client.pc
     include/Makefile
     include/osmocom/Makefile
+    include/osmocom/sdp/Makefile
     include/osmocom/mgcp_client/Makefile
     include/osmocom/mgcp/Makefile
     src/Makefile
+    src/libosmo-sdp/Makefile
     src/libosmo-mgcp-client/Makefile
     src/libosmo-mgcp/Makefile
     src/osmo-mgw/Makefile
@@ -197,6 +201,7 @@ AC_OUTPUT(
     tests/atlocal
     tests/mgcp_client/Makefile
     tests/mgcp/Makefile
+    tests/sdp/Makefile
     doc/Makefile
     doc/examples/Makefile
     doc/manuals/Makefile

contrib/osmo-mgw.spec.in

@@ -29,31 +29,30 @@ BuildRequires:  pkgconfig >= 0.20
 %if 0%{?suse_version}
 BuildRequires:  systemd-rpm-macros
 %endif
-BuildRequires:  pkgconfig(libosmo-netif) >= 1.2.0
-BuildRequires:  pkgconfig(libosmocore) >= 1.7.0
-BuildRequires:  pkgconfig(libosmoctrl) >= 1.7.0
-BuildRequires:  pkgconfig(libosmogsm) >= 1.7.0
-BuildRequires:  pkgconfig(libosmovty) >= 1.7.0
-BuildRequires:  pkgconfig(libosmocoding) >= 1.7.0
-BuildRequires:  pkgconfig(libosmoabis) >= 1.3.0
-BuildRequires:  pkgconfig(libosmotrau) >= 1.3.0
-Requires(pre):  shadow
+BuildRequires:  pkgconfig(libosmo-netif) >= 1.4.0
+BuildRequires:  pkgconfig(libosmocore) >= 1.9.0
+BuildRequires:  pkgconfig(libosmoctrl) >= 1.9.0
+BuildRequires:  pkgconfig(libosmogsm) >= 1.9.0
+BuildRequires:  pkgconfig(libosmovty) >= 1.9.0
+BuildRequires:  pkgconfig(libosmocoding) >= 1.9.0
+BuildRequires:  pkgconfig(libosmoabis) >= 1.5.0
+BuildRequires:  pkgconfig(libosmotrau) >= 1.5.0
 %{?systemd_requires}
 
 %description
 OsmoMGW is Osmocom's Media Gateway for 2G and 3G circuit-switched mobile networks.
 
-%package -n libosmo-mgcp-client9
+%package -n libosmo-mgcp-client12
 Summary:        Osmocom's Media Gateway Control Protocol client library
 Group:          System/Libraries
 
-%description -n libosmo-mgcp-client9
+%description -n libosmo-mgcp-client12
 Osmocom's Media Gateway Control Protocol client library.
 
 %package -n libosmo-mgcp-client-devel
 Summary:        Development files for Osmocom's Media Gateway Control Protocol client library
 Group:          Development/Libraries/C and C++
-Requires:       libosmo-mgcp-client9 = %{version}
+Requires:       libosmo-mgcp-client12 = %{version}
 
 %description -n libosmo-mgcp-client-devel
 Osmocom's Media Gateway Control Protocol client librarary.
@@ -61,16 +60,6 @@ Osmocom's Media Gateway Control Protocol client librarary.
 This subpackage contains libraries and header files for developing
 applications that want to make use of libosmo-mgcp-client.
 
-%package -n libosmo-mgcp-devel
-Summary:        Development files for Osmocom's Media Gateway server library
-Group:          Development/Libraries/C and C++
-
-%description -n libosmo-mgcp-devel
-Osmocom's Media Gateway Control Protocol server library.
-
-This subpackage contains libraries and header files for developing
-applications that want to make use of libosmo-mgcp.
-
 %prep
 %setup -q
 
@@ -91,8 +80,8 @@ find %{buildroot} -type f -name "*.la" -delete -print
 %check
 make %{?_smp_mflags} check || (find . -name testsuite.log -exec cat {} +)
 
-%post   -n libosmo-mgcp-client9 -p /sbin/ldconfig
-%postun -n libosmo-mgcp-client9 -p /sbin/ldconfig
+%post   -n libosmo-mgcp-client12 -p /sbin/ldconfig
+%postun -n libosmo-mgcp-client12 -p /sbin/ldconfig
 
 %if 0%{?suse_version}
 %preun
@@ -102,22 +91,15 @@ make %{?_smp_mflags} check || (find . -name testsuite.log -exec cat {} +)
 %service_del_postun osmo-mgw.service
 
 %pre
-getent group osmocom >/dev/null || groupadd --system osmocom
-getent passwd osmocom >/dev/null || useradd --system --gid osmocom --home-dir /var/lib/osmocom \
-                                            --shell /sbin/nologin --comment "Open Source Mobile Communications" osmocom
 %service_add_pre osmo-mgw.service
 
 %post
 %service_add_post osmo-mgw.service
-chown osmocom:osmocom /etc/osmocom/osmo-mgw.cfg
-chmod 0660 /etc/osmocom/osmo-mgw.cfg
-chown root:osmocom /etc/osmocom
-chmod 2775 /etc/osmocom
 %endif
 
 %files
 %license COPYING
-%doc AUTHORS README
+%doc AUTHORS README.md
 %dir %{_docdir}/%{name}/examples
 %dir %{_docdir}/%{name}/examples/osmo-mgw
 %{_docdir}/%{name}/examples/osmo-mgw/osmo-mgw.cfg
@@ -127,8 +109,8 @@ chmod 2775 /etc/osmocom
 %dir %{_sysconfdir}/osmocom
 %config(noreplace) %{_sysconfdir}/osmocom/osmo-mgw.cfg
 
-%files -n libosmo-mgcp-client9
-%{_libdir}/libosmo-mgcp-client.so.9*
+%files -n libosmo-mgcp-client12
+%{_libdir}/libosmo-mgcp-client.so.12*
 
 %files -n libosmo-mgcp-client-devel
 %{_libdir}/libosmo-mgcp-client.so
@@ -137,9 +119,4 @@ chmod 2775 /etc/osmocom
 %dir %{_includedir}/osmocom/mgcp_client
 %{_includedir}/osmocom/mgcp_client/*.h
 
-%files -n libosmo-mgcp-devel
-%dir %{_includedir}/osmocom
-%dir %{_includedir}/osmocom/mgcp
-%{_includedir}/osmocom/mgcp/*.h
-
 %changelog

contrib/systemd/osmo-mgw.service

@@ -1,12 +1,13 @@
 [Unit]
 Description=Osmocom Media Gateway (MGW)
+After=network-online.target
+Wants=network-online.target
 
 [Service]
 Type=simple
+LimitNOFILE=65536
 StateDirectory=osmocom
 WorkingDirectory=%S/osmocom
-User=osmocom
-Group=osmocom
 Restart=always
 ExecStart=/usr/bin/osmo-mgw -s -c /etc/osmocom/osmo-mgw.cfg
 RestartSec=2

debian/changelog

@@ -1,3 +1,218 @@
+osmo-mgw (1.12.1) unstable; urgency=medium
+
+  [ Pau Espin Pedrol ]
+  * mgcp-client: Fix missing include in mgcp_client_pool.h
+  * mgcp-client: Introduce API osmo_mgcpc_ep_local_name()
+  * mgw: Configure IuUP if codec set during MDCX
+
+ -- Oliver Smith <osmith@sysmocom.de>  Thu, 28 Sep 2023 15:58:17 +0200
+
+osmo-mgw (1.12.0) unstable; urgency=medium
+
+  [ Philipp Maier ]
+  * mgcp_sdp: add spec reference
+  * mgcp_sdp: cosmetic: remove newline
+  * mgcp_endp: cosmetic move mgcp_endp_release to the end
+  * mgcp_endp: cosmetic: remove unnecessary new line
+  * mgcp_e1: fix log output
+  * mgcp_e1: be more frugal withe E1 line resources
+  * mgcp_client: fix sourcecode formatting
+  * mgcp_e1: fix typo
+  * mgcp_e1: rewrite comment
+  * mgcp_e1: rename e1_send to e1_send_ts_frame
+  * mgcp_e1: cosmetic: rewrite comment
+  * Revert "mgcp_codec: do not differentiate between oa and bwe when comparing codec"
+  * mgcp_codec: fix oa/bwe comparison in mgcp_codec_pt_translate()
+  * mgcp_codec: refactor payload type converstion
+  * mgcp_codec: cosmetic: remove line break in api-doc
+  * mgcp_network: fix apidoc
+  * mgcp_vty: add warnings for deprecated config options
+  * mgcp_codec: move mgcp_codec_decide down
+  * mgcp_codec: fix codec decision
+  * mgcp_network: do not deliver RTP packets with unpatched PT
+  * mgcp_codec: be sensitive about IuFP when checking codecs
+  * mgcp_client.h: also add spec ref to the other 3gpp defined payload types
+
+  [ Harald Welte ]
+  * cosmetic: Fix grammar suggesting reading _the_ user manual
+
+  [ arehbein ]
+  * Transition to use of 'telnet_init_default'
+
+  [ Oliver Smith ]
+  * mgcp_client: mgcp_msg_gen: add more error logs
+  * mgcp_client_pool: add mgcp_client_pool_empty()
+  * Cosmetic: mgcp_client: fix typo
+  * debian: set compat level to 10
+  * systemd: depend on networking-online.target
+  * Cosmetic: fix a typo
+  * mgcp_client: check rc of map_str_to_codec
+
+  [ Pau Espin Pedrol ]
+  * mgcp_network: Unregister osmo_fd before closing fd
+  * mgcp-client: Call osmo_fd_unregister() before closing and changing bfd->fd
+  * mgcp-client: Drop unused struct mgcp_client field
+  * mgcp_client: Introduce mgcp_client_conf_alloc(), deprecate mgcp_client_conf_init()
+  * mgcp-client: Move some static functions further above
+  * mgw: Allow auditing speciall 'null' endpoint
+  * mgcp-client: Add keepalive feature
+  * mgcp_client: pool: Only pick clients with an MGCP link considered to be UP
+  * mgcp-client: Always mark client as UP if keepalive request-interval disabled
+  * mgcp-client: Mark client as UP when keepalive request-interval/timeout is disabled through VTY
+
+  [ Vadim Yanitskiy ]
+  * */Makefile.am: libraries shall not be in AM_LDFLAGS
+  * tests: use -no-install libtool flag to avoid ./lt-* scripts
+  * tests: $(BUILT_SOURCES) is not defined, depend on osmo-mgw
+  * copyright: fix typo: sysmocom s/s.m.f.c./s.f.m.c./ GmbH
+
+  [ Neels Hofmeyr ]
+  * mgcp_find_section_end(): skip spaces at start of SDP
+  * mgcp_client: simpler error handling
+  * mgcp: fix "L: a:" header parsing: heed ";" separator
+  * mgcp_client: tweak extract_codec_name() implementation
+
+  [ Andreas Eversberg ]
+  * ASCI: Add new mode for voice group/broadcast call
+  * ASCI: Support conference briding with 1..n connections
+
+ -- Pau Espin Pedrol <pespin@sysmocom.de>  Tue, 12 Sep 2023 14:48:51 +0200
+
+osmo-mgw (1.11.0) unstable; urgency=medium
+
+  [ Pau Espin Pedrol ]
+  * mgcp-client: Remove impossible code path
+  * mgcp_osmux: Drop duplicated conn_osmux_release_cid() in code path
+  * Use Osmux default port define from libosmo-netif
+  * osmux: Use new osmux APIs to let libosmo-netif alloc struct osmux_out_handle
+  * mgw: Fix osmux conn local IP selection
+  * cosmetic: osmux: Fix wrong indentation
+  * mgw: Use X-Osmux string define
+  * Add Osmux log category
+  * cosmetic: main: Properly format log_info_cat
+  * osmux: Use better name for function which may allocate a new struct
+  * osmux: Use osmo_sockaddr wherever possible
+  * osmux: Log refcounting of osmux_handle_list
+  * osmux: Fix memleak on error code path
+  * osmux: don't store conn ptr inside shared osmux_handle
+  * osmux: set log level of expected code path to INFO
+  * cosmetic: vty: Fix indentation whitespace
+  * osmux: Log sendto() error
+  * cosmetic: mgcp_conn.h: fix indentation whitespace
+  * osmux: Attach osmux to virtual trunk
+  * osmux: Clean up helper macro osmux_chunk_length()
+  * osmux: Get rid of static NULL talloc context
+  * Fix typo in ratectr description
+  * mgcp_conn: rename field s/rate_ctr_group/ctrg/g
+  * Use 'static const' instead of 'const static' everywhere
+  * osmux: Add connection and global rate counters
+  * cosmetic: osmux: Fix formatting of if-else brackets
+  * osmux: Rename field osmux usage policy and define it with proper type
+  * Use bool type instead of int in config field
+  * osmux: Support local CID != remote CID
+  * osmux: Fix incorrect rate_ctr_group used in mgcp_osmux.c
+  * osmux: Improve per-conn tx rate counters
+  * vty: show per-connection Osmux VTY stats
+  * osmux: Rename field s/init/initialized
+  * osmux: Allocate rate counters during initialization of osmux conn
+  * cosmetic: osmux: Drop extra empty line
+  * osmux: Drop unneeded comment block
+  * osmux: Lower log level when osmux batch received for unknown CID
+  * osmux: Keep decoding osmux pkt if a batch contains an unknown CID
+  * Allocate struct osmux_in_handle through new libosmo-netif APIs
+  * osmux: Drop logging of osmux internal counters
+  * osmux: cleanup misleading code calling rtp_bridge_cb
+  * osmux: Unify rtp_conn osmux type into a single type
+  * osmux: Match remote address in osmux_conn_lookup()
+  * osmux: Fill in from_addr in struct osmo_rtp_msg_ctx
+  * osmux: Log remote address upon rx of osmux pkt
+  * send_dummy: Use proper condition to test if conn is osmux
+  * Fix regression in detection of legacy dummy packets
+  * Use new libosmocore API osmo_sockaddr_is_any()
+  * Get rid of separate rtp_port field
+  * osmux: Use available API to check if remote end is known
+  * Add Osmux IPv6 support
+  * Clean up local var pointers in mgcp_get_local_addr()
+  * osmux: Change couple log lines to OSMUX category
+  * osmux: Add square brackets around IPv6 address to distinguish port in log line
+  * osmux: Drop unused role parameter
+  * osmux: cosmetic: Fix indentation
+  * Check once if remote addr is available when sending dummy packet
+  * osmux: Simplify and constify param passing
+  * osmux: Set conn->type during osmux_init_conn()
+  * osmux: Make conn_osmux_{allocate,release}_local_cid() APIs static
+  * osmux: Define osmux_dummy cfg as boolean
+  * osmux: Move setting OSMUX_STATE_DISABLED to initializer function
+  * osmux: Erase references to bsc-nat
+  * mgcp_conn_dump(): Separate dump for osmux and iuup connections
+  * osmux: Introduce osmux peer-behind-nat (on|off) and rework conn activation
+  * osmux: Clean up mgcp_config osmux fields
+  * cosmetic: Fix typo in comment
+  * mgcp-client: pool: Improve documentation of some internal fields
+  * mgcp-client: Avoid double iteration picking client from pool
+  * mgcp-client: Fix typo in internal function name
+  * mgcp-client: Rename internal field in mgcp_client_pool
+  * mgcp-client: Move & rename helper function outside of vty code
+  * mgcp-client: Create alloc() and free() internal APIs for mgcp_client_pool_member
+  * mgcp-client: Move internal API acting on mgcp_client_pool to the correct file section
+  * mgcp-client: Refactor reinit of mgcp clients
+  * mgcp-client: Rearrange order of structs and APIs in header
+  * mgcp-client: Rearrange internal backpointers
+  * mgcp-client: Introduce APIs to manually select mgcp_client from pool
+  * mgcp-client: vty: Write deprecation warning using non-mgw nodes
+  * mgcp-client: Use random free local port by default
+  * mgcp-client: Convert users supporting new MGW Pool VTY node during write-config
+  * mgcp-client: Introduce API mgcp_client_pool_config_write
+  * mgcp-client: Add new VTY commands under mgw node without mgw prefix
+  * mgcp-client: Fix 'mgw endpoint-range' command dropped from old VTY node
+  * mgcp-client: Refactor system keeping old users not calling mgcp_client_pool_config_write() working
+  * mgcp-client: Fix no 'mgw ' prefix written in old VTY node
+  * Fix misleading error log
+  * mgcp_send: Use mgcp_conn_rtp_is_iuup() helper
+  * cosmetic: Clarify and fix typos in comment
+  * mgw: Log unexpected RTP AMR OA-vs-BE payload
+  * Rename and move func checking if amr mode is explicitly configured
+  * mgw: rx_rtp(): reorder checks and handlings
+  * mgw: Rename s/mgcp_send_rtp/mgcp_conn_rtp_dispatch_rtp/
+  * osmux: Rename function and pass msgb directly to it
+  * osmux: Make sure RTP AMR feed to osmux is in octet-aligned mode
+  * Improve logging on AMR OA<->BWE conversion failure
+  * osmux: Rotate over available Osmux CID when allocating a new one
+  * osmux: Use new osmux_xfrm_input API to set name on each link
+  * iuup: Use osmo_amr_ft_valid() API
+
+  [ Vadim Yanitskiy ]
+  * libosmo-mgcp-client: add -no-undefined to *_la_LDFLAGS
+
+  [ Philipp Maier ]
+  * mgcp_e1: fix apidoc
+  * mgcp_network: improve coment
+
+  [ Max ]
+  * Set working directory in systemd service file
+  * Add realtime scheduling and set priority in service file
+  * ctrl: take both address and port from vty config
+
+  [ Harald Welte ]
+  * Make osmo_mgcpc_ep_fsm_pre_term() static
+  * Support building with -Werror=strict-prototypes / -Werror=old-style-definition
+  * Add -Werror=implicit-int -Werror=int-conversion -Werror=old-style-definition
+  * update outdated vty copyright statement
+
+  [ Oliver Smith ]
+  * mgcp_client_pool.h: add missing stdbool include
+  * Fix various typos
+  * mgcp_client: add new clearmode codec
+
+  [ Neels Hofmeyr ]
+  * AMR->IuUP: do not crash on AMR data before IuUP Init
+  * AMR->IuUP: properly translate Q -> FQC
+  * IuUP->AMR: do not patch payload type a second time
+  * IuUP->AMR: log whether converting to AMR OA or BE
+  * AMR->IuUP: log conversion, like for the flipside
+
+ -- Pau Espin Pedrol <pespin@sysmocom.de>  Tue, 07 Feb 2023 16:58:41 +0100
+
 osmo-mgw (1.10.0) unstable; urgency=medium
 
   [ Eric ]

debian/compat

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

debian/control

@@ -2,14 +2,14 @@ Source: osmo-mgw
 Section: net
 Priority: extra
 Maintainer: Osmocom team <openbsc@lists.osmocom.org>
-Build-Depends: debhelper (>=9),
+Build-Depends: debhelper (>= 10),
                dh-autoreconf,
                pkg-config,
                autotools-dev,
-               libosmocore-dev (>= 1.7.0),
-               libosmo-netif-dev (>= 1.2.0),
-               libosmo-abis-dev (>= 1.3.0),
-               osmo-gsm-manuals-dev (>= 1.3.0)
+               libosmocore-dev (>= 1.9.0),
+               libosmo-netif-dev (>= 1.4.0),
+               libosmo-abis-dev (>= 1.5.0),
+               osmo-gsm-manuals-dev (>= 1.5.0)
 Standards-Version: 3.9.8
 Vcs-Git: https://gitea.osmocom.org/cellular-infrastructure/osmo-mgw
 Vcs-Browser: https://gitea.osmocom.org/cellular-infrastructure/osmo-mgw
@@ -18,10 +18,10 @@ Homepage: https://osmocom.org/projects/osmo-mgw
 Package: osmo-mgw
 Architecture: any
 Multi-Arch: foreign
-Depends: ${misc:Depends}, ${shlibs:Depends}, adduser
+Depends: ${misc:Depends}, ${shlibs:Depends}
 Description: OsmoMGW: Osmocom's Media Gateway for 2G and 3G circuit-switched mobile networks
 
-Package: libosmo-mgcp-client9
+Package: libosmo-mgcp-client12
 Section: libs
 Architecture: any
 Multi-Arch: same
@@ -33,7 +33,7 @@ Package: libosmo-mgcp-client-dev
 Section: libdevel
 Architecture: any
 Multi-Arch: same
-Depends: libosmo-mgcp-client9 (= ${binary:Version}), ${misc:Depends}
+Depends: libosmo-mgcp-client12 (= ${binary:Version}), ${misc:Depends}
 Description: libosmo-mgcp-client: Osmocom's Media Gateway Control Protocol client utilities
 
 Package: osmo-mgw-doc

debian/copyright

@@ -6,7 +6,7 @@ Files:     *
 Copyright: 2009-2014 On-Waves
            2009-2015 Holger Hans Peter Freyther <zecke@selfish.org>
            2013 Jacob Erlbeck <jerlbeck@sysmocom.de>
-           2016-2017 sysmocom s.m.f.c. GmbH <info@sysmocom.de>
+           2016-2017 sysmocom s.f.m.c. GmbH <info@sysmocom.de>
 License:   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
@@ -22,7 +22,7 @@ License:   AGPL-3.0+
  along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 Files:     src/libosmo-mgcp-client/* include/osmocom/mgcp_client/*
-Copyright: 2016 by sysmocom s.m.f.c. GmbH <info@sysmocom.de>
+Copyright: 2016 by sysmocom s.f.m.c. GmbH <info@sysmocom.de>
            Based on OpenBSC interface to quagga VTY (libmsc/vty_interface_layer3.c)
            2009 by Harald Welte <laforge@gnumonks.org>
            2009-2011 by Holger Hans Peter Freyther

debian/postinst

@@ -1,39 +0,0 @@
-#!/bin/sh -e
-
-# Create 'osmocom' user and group (if it doesn't exist yet) and adjust permissions
-# of directories which are not automatically adjusted by systemd from previous (root-owned)
-# install.
-
-# N. B: the user is intentionally NOT removed during package uninstall:
-# see https://wiki.debian.org/AccountHandlingInMaintainerScripts for reasoning.
-chperms() {
-	# chperms <user> <group> <perms> <file>
-	if ! OVERRIDE=`dpkg-statoverride --list $4 2>&1`; then
-		if [ -e $4 ]; then
-			chown $1:$2 $4
-			chmod $3 $4
-		fi
-	fi
-}
-
-case "$1" in
-  configure)
-    if ! getent passwd osmocom > /dev/null; then
-        adduser --quiet \
-                --system \
-                --group \
-                --no-create-home \
-                --disabled-password \
-                --home /var/lib/osmocom \
-                --gecos "Open Source Mobile Communications" \
-                osmocom
-    fi
-# Set permissions according to https://www.debian.org/doc/debian-policy/ch-files.html#s-permissions-owners
-    chperms osmocom osmocom 0660 /etc/osmocom/osmo-mgw.cfg
-    chperms root osmocom 2775 /etc/osmocom
-  ;;
-esac
-
-# dh_installdeb(1) will replace this with shell code automatically
-# generated by other debhelper scripts.
-#DEBHELPER#

doc/examples/osmo-mgw/osmo-mgw-abis_e1.cfg

@@ -1,6 +1,14 @@
 !
 ! MGCP configuration example
 !
+log stderr
+ logging color 1
+ logging print category-hex 0
+ logging print category 1
+ logging timestamp 0
+ logging print file basename last
+ logging print level 1
+
 e1_input
  e1_line 0 driver dahdi
  e1_line 0 port 0

doc/examples/osmo-mgw/osmo-mgw.cfg

@@ -1,6 +1,14 @@
 !
 ! MGCP configuration example
 !
+log stderr
+ logging color 1
+ logging print category-hex 0
+ logging print category 1
+ logging timestamp 0
+ logging print file basename last
+ logging print level 1
+
 mgcp
   bind ip 127.0.0.1
   rtp port-range 4002 16000

doc/manuals/chapters/mgcp_endpoints.adoc

@@ -91,4 +91,10 @@ encoding/decoding for 16K and 8K subslots. Endpoints with other bitrates are
 not yet useable.
 
 NOTE: the VTY command "show mgcp" can be used to get a list of all available
-endpoints (including identifiers)
+endpoints (including identifiers)
+
+=== The `null` endpoint
+
+OsmoMGW offers a special `null@<domain>` endpoint which can be audited at all times.
+This is useful for MGCP clients who wish to submit requests to OsmoMGW
+periodically to find out whether it is still reachable and in a working state.

doc/manuals/chapters/running.adoc

@@ -23,3 +23,20 @@ arguments:
 	Disable colors for logging to stderr. This has mostly been
 	deprecated by VTY based logging configuration, see <<logging>>
 	for more information.
+
+
+=== Configure limits
+
+When servicing hundreds of media endpoints, it may be necessary to adjust the
+operating system's limit on open file descriptors for the osmo-mgw process. A
+typical default limit imposed by operating systems is 1024; this would be
+exceeded by, for example, about 256 active voice calls with 4 RTP/RTPC ports
+each, 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-mgw, which practically rules out failure from running out of file
+descriptors anywhere (<16,000 active calls).
+
+When using systemd, the file descriptor limit may be adjusted in the service
+file by the `LimitNOFILE` setting ("Number of Open FILE descriptors"). OsmoMGW
+ships a systemd service file with a high LimitNOFILE setting.

include/Makefile.am

@@ -3,10 +3,16 @@ SUBDIRS = \
 	$(NULL)
 
 nobase_include_HEADERS = \
+	osmocom/mgcp_client/defs.h \
 	osmocom/mgcp_client/mgcp_client.h \
 	osmocom/mgcp_client/mgcp_client_endpoint_fsm.h \
 	osmocom/mgcp_client/mgcp_client_fsm.h \
 	osmocom/mgcp_client/mgcp_client_pool.h \
+	osmocom/sdp/fmtp.h \
+	osmocom/sdp/sdp_strings.h \
+	$(NULL)
+
+noinst_HEADERS = \
 	osmocom/mgcp/mgcp.h \
 	osmocom/mgcp/mgcp_common.h \
 	osmocom/mgcp/osmux.h \

include/osmocom/Makefile.am

@@ -1,4 +1,5 @@
 SUBDIRS = \
+	sdp \
 	mgcp_client \
 	mgcp \
 	$(NULL)

include/osmocom/mgcp/Makefile.am

@@ -6,7 +6,6 @@ noinst_HEADERS = \
 	mgcp_endp.h \
 	mgcp_sdp.h \
 	mgcp_codec.h \
-	mgcp_ctrl.h \
 	mgcp_trunk.h \
 	debug.h \
 	mgcp_ratectr.h \

include/osmocom/mgcp/mgcp.h

@@ -138,8 +138,6 @@ struct mgcp_config {
 	mgcp_processing rtp_processing_cb;
 	mgcp_processing_setup setup_rtp_processing_cb;
 
-	mgcp_get_format get_net_downlink_format_cb;
-
 	struct osmo_wqueue gw_fd;
 
 	struct mgcp_port_range net_ports;

include/osmocom/mgcp/mgcp_codec.h

@@ -13,9 +13,10 @@ struct mgcp_conn_rtp;
 void mgcp_codec_summary(struct mgcp_conn_rtp *conn);
 void mgcp_codec_reset_all(struct mgcp_conn_rtp *conn);
 int mgcp_codec_add(struct mgcp_conn_rtp *conn, int payload_type, const char *audio_name, const struct mgcp_codec_param *param);
-int mgcp_codec_decide(struct mgcp_conn_rtp *conn);
-int mgcp_codec_pt_translate(struct mgcp_conn_rtp *conn_src, struct mgcp_conn_rtp *conn_dst, int payload_type);
+int mgcp_codec_add2(struct mgcp_conn_rtp *conn, int payload_type, const char *audio_name, const char *fmtp);
+int mgcp_codec_decide(struct mgcp_conn_rtp *conn_src, struct mgcp_conn_rtp *conn_dst);
 const struct mgcp_rtp_codec *mgcp_codec_pt_find_by_subtype_name(struct mgcp_conn_rtp *conn,
 								const char *subtype_name, unsigned int match_nr);
 bool mgcp_codec_amr_align_mode_is_indicated(const struct mgcp_rtp_codec *codec);
 bool mgcp_codec_amr_is_octet_aligned(const struct mgcp_rtp_codec *codec);
+struct mgcp_rtp_codec *mgcp_codec_from_pt(struct mgcp_conn_rtp *conn, int payload_type);

include/osmocom/mgcp/mgcp_common.h

@@ -47,6 +47,7 @@ enum mgcp_connection_mode {
 	MGCP_CONN_SEND_ONLY = 2,
 	MGCP_CONN_RECV_SEND = MGCP_CONN_RECV_ONLY | MGCP_CONN_SEND_ONLY,
 	MGCP_CONN_LOOPBACK  = 4 | MGCP_CONN_RECV_SEND,
+	MGCP_CONN_CONFECHO  = 8 | MGCP_CONN_RECV_SEND,
 };
 
 #define MGCP_X_OSMO_IGN_HEADER "X-Osmo-IGN:"
@@ -58,7 +59,7 @@ enum mgcp_x_osmo_ign {
 	MGCP_X_OSMO_IGN_CALLID = 1,
 };
 
-/* Codec parameters (communicated via SDP/fmtp) */
+/* Deprecated. Use the new fmtp string instead. */
 struct mgcp_codec_param {
 	bool amr_octet_aligned_present;
 	bool amr_octet_aligned;
@@ -67,11 +68,11 @@ struct mgcp_codec_param {
 /* Ensure that the msg->l2h is NUL terminated. */
 static inline int mgcp_msg_terminate_nul(struct msgb *msg)
 {
-	unsigned char *tail = msg->l2h + msgb_l2len(msg); /* char after l2 data */
+	unsigned char *tail = msg->tail; /* char after l2 data */
 	if (tail[-1] == '\0')
 		/* nothing to do */;
 	else if (msgb_tailroom(msg) > 0)
-		tail[0] = '\0';
+		msgb_put_u8(msg, (uint8_t)'\0');
 	else if (tail[-1] == '\r' || tail[-1] == '\n')
 		tail[-1] = '\0';
 	else {

include/osmocom/mgcp/mgcp_conn.h

@@ -49,6 +49,11 @@ enum mgcp_conn_rtp_type {
 	MGCP_RTP_OSMUX,
 	MGCP_RTP_IUUP,
 };
+extern const struct value_string mgcp_conn_rtp_type_names[];
+static inline const char *mgcp_conn_rtp_type_name(enum mgcp_conn_rtp_type val)
+{
+	return get_value_string(mgcp_conn_rtp_type_names, val);
+}
 
 /*! Connection type, specifies which member of the union "u" in mgcp_conn
  *  contains a useful connection description (currently only RTP) */

include/osmocom/mgcp/mgcp_ctrl.h

@@ -1,24 +0,0 @@
-/*
- * (C) 2020 by Harald Welte <laforge@gnumonks.org>
- * 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/>.
- *
- */
-
-#pragma once
-
-struct ctrl_handle *mgw_ctrl_interface_setup(struct mgcp_config *cfg,
-                                             const char *bind_addr, uint16_t port);
-

include/osmocom/mgcp/mgcp_e1.h

@@ -23,5 +23,5 @@ static const uint8_t e1_offsets[] = { 0, 0, 4, 0, 2, 4, 6, 0, 1, 2, 3, 4, 5, 6,
 
 int mgcp_e1_endp_equip(struct mgcp_endpoint *endp, uint8_t ts, uint8_t ss, uint8_t offs);
 void mgcp_e1_endp_update(struct mgcp_endpoint *endp);
-void mgcp_e1_endp_release(struct mgcp_endpoint *endp);
+void mgcp_e1_endp_release(struct mgcp_endpoint *endp, uint8_t ts);
 int mgcp_e1_send_rtp(struct mgcp_endpoint *endp, struct mgcp_rtp_codec *codec, struct msgb *msg);

include/osmocom/mgcp/mgcp_endp.h

@@ -130,10 +130,10 @@ struct mgcp_endpoint {
 };
 
 struct mgcp_endpoint *mgcp_endp_alloc(struct mgcp_trunk *trunk, unsigned int index);
-void mgcp_endp_release(struct mgcp_endpoint *endp);
 int mgcp_endp_claim(struct mgcp_endpoint *endp, const char *callid);
 void mgcp_endp_update(struct mgcp_endpoint *endp);
 bool mgcp_endp_is_wildcarded(const char *epname);
+bool mgcp_endp_is_null(const char *epname);
 struct mgcp_endpoint *mgcp_endp_by_name_trunk(int *cause, const char *epname,
 					      const struct mgcp_trunk *trunk);
 struct mgcp_endpoint *mgcp_endp_by_name(int *cause, const char *epname,
@@ -145,3 +145,4 @@ void mgcp_endp_strip_name(char *epname_stripped, const char *epname,
 			 const struct mgcp_trunk *trunk);
 struct mgcp_endpoint *mgcp_endp_find_specific(const char *epname,
 			const struct mgcp_trunk *trunk);
+void mgcp_endp_release(struct mgcp_endpoint *endp);

include/osmocom/mgcp/mgcp_network.h

@@ -83,8 +83,11 @@ struct mgcp_rtp_codec {
 	char audio_name[64];
 	char subtype_name[64];
 
+	/* Deprecated. Use the new fmtp string instead. */
 	bool param_present;
 	struct mgcp_codec_param param;
+
+	char fmtp[256];
 };
 
 /* 'mgcp_rtp_end': basically a wrapper around the RTP+RTCP ports */
@@ -108,7 +111,6 @@ struct mgcp_rtp_end {
 	int  frames_per_packet;
 	uint32_t packet_duration_ms;
 	int maximum_packet_time; /* -1: not set */
-	char *fmtp_extra;
 	/* are we transmitting packets (true) or dropping (false) outbound packets */
 	bool output_enabled;
 	/* FIXME: This parameter can be set + printed, but is nowhere used! */

include/osmocom/mgcp/mgcp_trunk.h

@@ -27,12 +27,9 @@ struct mgcp_trunk {
 	unsigned int trunk_nr;
 	enum mgcp_trunk_type trunk_type;
 
-	char *audio_fmtp_extra;
 	int audio_send_ptime;
 	int audio_send_name;
 
-	int no_audio_transcoding;
-
 	int omit_rtcp;
 	int keepalive_interval;
 
@@ -66,7 +63,7 @@ struct mgcp_trunk {
 		/* E1 specific */
 		struct {
 			unsigned int vty_line_nr;
-			bool ts_in_use[NUM_E1_TS-1];
+			uint8_t ts_usecount[NUM_E1_TS-1];
 			struct osmo_i460_timeslot i460_ts[NUM_E1_TS-1];
 			/* Note: on an E1 line TS 0 is devoted to framing and
 			 * alignment and therefore only NUM_E1_TS-1 timeslots

include/osmocom/mgcp_client/defs.h

@@ -0,0 +1,7 @@
+#include <osmocom/core/defs.h>
+
+#if BUILDING_LIBOSMOMGCPCLIENT
+# define OSMO_DEPRECATED_OUTSIDE_LIBOSMOMGCPCLIENT(text)
+#else
+# define OSMO_DEPRECATED_OUTSIDE_LIBOSMOMGCPCLIENT(text) OSMO_DEPRECATED(text)
+#endif

include/osmocom/mgcp_client/mgcp_client.h

@@ -3,6 +3,7 @@
 #include <stdint.h>
 #include <arpa/inet.h>
 
+#include <osmocom/mgcp_client/defs.h>
 #include <osmocom/mgcp_client/mgcp_common.h>
 
 /* See also: RFC 3435, chapter 3.5 Transmission over UDP */
@@ -10,7 +11,7 @@
 #define MGCP_CLIENT_LOCAL_PORT_DEFAULT 0
 #define MGCP_CLIENT_REMOTE_ADDR_DEFAULT "127.0.0.1"
 #define MGCP_CLIENT_REMOTE_PORT_DEFAULT 2427
-
+#define MGCP_CLIENT_KEEPALIVE_DEFAULT_ENDP "null"
 #define MGCP_CLIENT_MGW_STR "Configure MGCP connection to Media Gateway\n"
 
 struct msgb;
@@ -35,6 +36,12 @@ struct mgcp_client_conf {
 
 	/* human readable name / description */
 	char *description;
+
+	struct {
+		uint32_t timeout_sec;
+		uint32_t req_interval_sec;
+		char req_endpoint_name[MGCP_ENDPOINT_MAXLEN];
+	} keepalive;
 };
 
 typedef unsigned int mgcp_trans_id_t;
@@ -45,11 +52,12 @@ enum mgcp_codecs {
 	CODEC_GSM_8000_1 = 3,
 	CODEC_PCMA_8000_1 = 8,
 	CODEC_G729_8000_1 = 18,
-	CODEC_GSMEFR_8000_1 = 110,
-	CODEC_GSMHR_8000_1 = 111,
-	CODEC_AMR_8000_1 = 112,
-	CODEC_AMRWB_16000_1 = 113,
+	CODEC_GSMEFR_8000_1 = 110,	/* 3GPP TS 48.103 table 5.4.2.2.1 */
+	CODEC_GSMHR_8000_1 = 111,	/* 3GPP TS 48.103 table 5.4.2.2.1 */
+	CODEC_AMR_8000_1 = 112,		/* 3GPP TS 48.103 table 5.4.2.2.1 */
+	CODEC_AMRWB_16000_1 = 113,	/* 3GPP TS 48.103 table 5.4.2.2.1 */
 	CODEC_IUFP = 96,
+	CODEC_CLEARMODE = 120,		/* 3GPP TS 48.103 table 5.4.2.2.1 */
 };
 /* Note: when new codec types are added, the corresponding value strings
  * in mgcp_client.c (codec_table) must be updated as well. Enumerations
@@ -69,29 +77,12 @@ struct ptmap {
 
 	/*! payload type number (96-127) */
 	unsigned int pt;
+
+	/*! the MGCP 'a=fmtp:N <...>' string, e.g. "mode-set=1,2,3;octet-align=0". */
+	char fmtp[256];
 };
 
-struct mgcp_response_head {
-	int response_code;
-	mgcp_trans_id_t trans_id;
-	char comment[MGCP_COMMENT_MAXLEN];
-	char conn_id[MGCP_CONN_ID_MAXLEN];
-	char endpoint[MGCP_ENDPOINT_MAXLEN];
-	bool x_osmo_osmux_use;
-	uint8_t x_osmo_osmux_cid;
-};
-
-struct mgcp_response {
-	char *body;
-	struct mgcp_response_head head;
-	uint16_t audio_port;
-	char audio_ip[INET6_ADDRSTRLEN];
-	unsigned int ptime;
-	enum mgcp_codecs codecs[MGCP_MAX_CODECS];
-	unsigned int codecs_len;
-	struct ptmap ptmap[MGCP_MAX_CODECS];
-	unsigned int ptmap_len;
-};
+int ptmap_cmp(const struct ptmap *a, const struct ptmap *b);
 
 enum mgcp_verb {
 	MGCP_VERB_CRCX,
@@ -101,38 +92,8 @@ enum mgcp_verb {
 	MGCP_VERB_RSIP,
 };
 
-#define MGCP_MSG_PRESENCE_ENDPOINT	0x0001
-#define MGCP_MSG_PRESENCE_CALL_ID	0x0002
-#define MGCP_MSG_PRESENCE_CONN_ID	0x0004
-#define MGCP_MSG_PRESENCE_AUDIO_IP	0x0008
-#define MGCP_MSG_PRESENCE_AUDIO_PORT	0x0010
-#define MGCP_MSG_PRESENCE_CONN_MODE	0x0020
-#define MGCP_MSG_PRESENCE_X_OSMO_OSMUX_CID 0x4000
-#define MGCP_MSG_PRESENCE_X_OSMO_IGN	0x8000
-
-struct mgcp_msg {
-	enum mgcp_verb verb;
-	/* See MGCP_MSG_PRESENCE_* constants */
-	uint32_t presence;
-	char endpoint[MGCP_ENDPOINT_MAXLEN];
-	unsigned int call_id;
-	char *conn_id;
-	uint16_t audio_port;
-	char *audio_ip;
-	enum mgcp_connection_mode conn_mode;
-	unsigned int ptime;
-	enum mgcp_codecs codecs[MGCP_MAX_CODECS];
-	unsigned int codecs_len;
-	struct ptmap ptmap[MGCP_MAX_CODECS];
-	unsigned int ptmap_len;
-	uint32_t x_osmo_ign;
-	bool x_osmo_osmux_use;
-	int x_osmo_osmux_cid; /* -1 is wildcard */
-	bool param_present;
-	struct mgcp_codec_param param;
-};
-
-void mgcp_client_conf_init(struct mgcp_client_conf *conf);
+struct mgcp_client_conf *mgcp_client_conf_alloc(void *ctx);
+void mgcp_client_conf_init(struct mgcp_client_conf *conf) OSMO_DEPRECATED_OUTSIDE_LIBOSMOMGCPCLIENT("use mgcp_client_conf_alloc() (or even better, switch to the mgcp_client_pool API!)");
 void mgcp_client_vty_init(void *talloc_ctx, int node, struct mgcp_client_conf *conf);
 int mgcp_client_config_write(struct vty *vty, const char *indent);
 struct mgcp_client_conf *mgcp_client_conf_actual(struct mgcp_client *mgcp);
@@ -152,20 +113,8 @@ const char *mgcp_client_rtpbridge_wildcard(const struct mgcp_client *mgcp);
 const char *mgcp_client_e1_epname(void *ctx, const struct mgcp_client *mgcp, uint8_t trunk_id, uint8_t ts,
 				  uint8_t rate, uint8_t offset);
 
-/* Invoked when an MGCP response is received or sending failed.  When the
- * response is passed as NULL, this indicates failure during transmission. */
-typedef void (* mgcp_response_cb_t )(struct mgcp_response *response, void *priv);
-int mgcp_response_parse_params(struct mgcp_response *r);
-
-int mgcp_client_tx(struct mgcp_client *mgcp, struct msgb *msg,
-		   mgcp_response_cb_t response_cb, void *priv);
-int mgcp_client_cancel(struct mgcp_client *mgcp, mgcp_trans_id_t trans_id);
-
 enum mgcp_connection_mode;
 
-struct msgb *mgcp_msg_gen(struct mgcp_client *mgcp, struct mgcp_msg *mgcp_msg);
-mgcp_trans_id_t mgcp_msg_trans_id(struct msgb *msg);
-
 extern const struct value_string mgcp_client_connection_mode_strs[];
 static inline const char *mgcp_client_cmode_name(enum mgcp_connection_mode mode)
 {

include/osmocom/mgcp_client/mgcp_client_endpoint_fsm.h

@@ -45,6 +45,7 @@ static inline void osmo_mgcpc_ep_ci_dlcx(struct osmo_mgcpc_ep_ci *ci)
 void osmo_mgcpc_ep_clear(struct osmo_mgcpc_ep *ep);
 
 const char *osmo_mgcpc_ep_name(const struct osmo_mgcpc_ep *ep);
+const char *osmo_mgcpc_ep_local_name(const struct osmo_mgcpc_ep *ep);
 const char *osmo_mgcpc_ep_ci_name(const struct osmo_mgcpc_ep_ci *ci);
 const char *osmo_mgcpc_ep_ci_id(const struct osmo_mgcpc_ep_ci *ci);
 struct mgcp_client *osmo_mgcpc_ep_client(const struct osmo_mgcpc_ep *ep);

include/osmocom/mgcp_client/mgcp_client_fsm.h

@@ -29,11 +29,11 @@ struct mgcp_conn_peer {
 	/*! RTP packetization interval (optional) */
 	unsigned int ptime;
 
-	/*! RTP codec list (optional) */
-	enum mgcp_codecs codecs[MGCP_MAX_CODECS];
-
-	/*! Number of codecs in RTP codec list (optional) */
-	unsigned int codecs_len;
+	/*! Deprecated. Use only ptmap[].codec in new code. */
+	enum mgcp_codecs codecs[MGCP_MAX_CODECS]
+		OSMO_DEPRECATED_OUTSIDE_LIBOSMOMGCPCLIENT("use ptmap[i].codec instead");
+	unsigned int codecs_len
+		OSMO_DEPRECATED_OUTSIDE_LIBOSMOMGCPCLIENT("use ptmap[] and ptmap_len instead");
 
 	/*! RTP payload type map (optional, only needed when payload types are
 	 * used that differ from what IANA/3GPP defines) */
@@ -57,18 +57,23 @@ struct mgcp_conn_peer {
 	 * address is set. If != MGCP_CONN_NONE, force this conn mode. */
 	enum mgcp_connection_mode conn_mode;
 
-	/*! If the codec requires additional format parameters (fmtp), those cann be set here, see also
-	 * mgcp_common.h */
-	bool param_present;
-	struct mgcp_codec_param param;
+	/*! Deprectated, use ptmap[].fmtp instead.
+	 * Global codec params. In case the codec requires additional format parameters (fmtp), those can be set
+	 * here, see also mgcp_common.h. The format parameters will be applied on all codecs where applicable. */
+	bool param_present OSMO_DEPRECATED_OUTSIDE_LIBOSMOMGCPCLIENT("use ptmap[].fmtp instead");
+	struct mgcp_codec_param param OSMO_DEPRECATED_OUTSIDE_LIBOSMOMGCPCLIENT("use ptmap[].fmtp instead");
 };
 
 struct osmo_fsm_inst *mgcp_conn_create(struct mgcp_client *mgcp, struct osmo_fsm_inst *parent_fi, uint32_t parent_term_evt,
-				       uint32_t parent_evt, struct mgcp_conn_peer *conn_peer);
-int mgcp_conn_modify(struct osmo_fsm_inst *fi, uint32_t parent_evt, struct mgcp_conn_peer *conn_peer);
-void mgcp_conn_delete(struct osmo_fsm_inst *fi);
+				       uint32_t parent_evt, struct mgcp_conn_peer *conn_peer)
+	OSMO_DEPRECATED_OUTSIDE_LIBOSMOMGCPCLIENT("use osmo_mgcpc_ep_alloc() and osmo_mgcpc_ep_ci_add() instead");
+int mgcp_conn_modify(struct osmo_fsm_inst *fi, uint32_t parent_evt, struct mgcp_conn_peer *conn_peer)
+	OSMO_DEPRECATED_OUTSIDE_LIBOSMOMGCPCLIENT("use osmo_mgcpc_ep_ci_request() instead");
+void mgcp_conn_delete(struct osmo_fsm_inst *fi)
+	OSMO_DEPRECATED_OUTSIDE_LIBOSMOMGCPCLIENT("use osmo_mgcpc_ep_ci_dlcx() instead");
 
-const char *mgcp_conn_get_ci(struct osmo_fsm_inst *fi);
+const char *mgcp_conn_get_ci(struct osmo_fsm_inst *fi)
+	OSMO_DEPRECATED_OUTSIDE_LIBOSMOMGCPCLIENT("use osmo_mgcpc_ep_ci.mgcp_ci_str instead");
 struct mgcp_client *mgcp_conn_get_client(struct osmo_fsm_inst *fi);
 
 const char *osmo_mgcpc_conn_peer_name(const struct mgcp_conn_peer *info);

include/osmocom/mgcp_client/mgcp_client_internal.h

@@ -1,6 +1,7 @@
 #pragma once
 
 #include <osmocom/core/write_queue.h>
+#include <osmocom/core/timer.h>
 
 #define MSGB_CB_MGCP_TRANS_ID 0
 
@@ -15,15 +16,36 @@ struct mgcp_client {
 	struct osmo_wqueue wq;
 	mgcp_trans_id_t next_trans_id;
 	struct llist_head responses_pending;
-	struct llist_head inuse_endpoints;
 	struct mgcp_client_pool_member *pool_member;
+	struct osmo_timer_list keepalive_tx_timer;
+	struct osmo_timer_list keepalive_rx_timer;
+	bool conn_up;
 };
 
-struct mgcp_inuse_endpoint {
-	struct llist_head entry;
-	uint16_t id;
+struct mgcp_response_head {
+	int response_code;
+	mgcp_trans_id_t trans_id;
+	char comment[MGCP_COMMENT_MAXLEN];
+	char conn_id[MGCP_CONN_ID_MAXLEN];
+	char endpoint[MGCP_ENDPOINT_MAXLEN];
+	bool x_osmo_osmux_use;
+	uint8_t x_osmo_osmux_cid;
 };
 
+struct mgcp_response {
+	char *body;
+	struct mgcp_response_head head;
+	uint16_t audio_port;
+	char audio_ip[INET6_ADDRSTRLEN];
+	unsigned int ptime;
+	struct ptmap ptmap[MGCP_MAX_CODECS];
+	unsigned int ptmap_len;
+};
+
+/* Invoked when an MGCP response is received or sending failed.  When the
+ * response is passed as NULL, this indicates failure during transmission. */
+typedef void (*mgcp_response_cb_t)(struct mgcp_response *response, void *priv);
+
 struct mgcp_response_pending {
 	struct llist_head entry;
 
@@ -39,3 +61,41 @@ struct mgcp_response_pending * mgcp_client_pending_add(
 					mgcp_trans_id_t trans_id,
 					mgcp_response_cb_t response_cb,
 					void *priv);
+
+#define MGCP_MSG_PRESENCE_ENDPOINT	0x0001
+#define MGCP_MSG_PRESENCE_CALL_ID	0x0002
+#define MGCP_MSG_PRESENCE_CONN_ID	0x0004
+#define MGCP_MSG_PRESENCE_AUDIO_IP	0x0008
+#define MGCP_MSG_PRESENCE_AUDIO_PORT	0x0010
+#define MGCP_MSG_PRESENCE_CONN_MODE	0x0020
+#define MGCP_MSG_PRESENCE_X_OSMO_OSMUX_CID 0x4000
+#define MGCP_MSG_PRESENCE_X_OSMO_IGN	0x8000
+
+struct mgcp_msg {
+	enum mgcp_verb verb;
+	/* See MGCP_MSG_PRESENCE_* constants */
+	uint32_t presence;
+	char endpoint[MGCP_ENDPOINT_MAXLEN];
+	unsigned int call_id;
+	char *conn_id;
+	uint16_t audio_port;
+	char *audio_ip;
+	enum mgcp_connection_mode conn_mode;
+	unsigned int ptime;
+	struct ptmap ptmap[MGCP_MAX_CODECS];
+	unsigned int ptmap_len;
+	uint32_t x_osmo_ign;
+	bool x_osmo_osmux_use;
+	int x_osmo_osmux_cid; /* -1 is wildcard */
+	bool param_present;
+	struct mgcp_codec_param param;
+};
+
+int mgcp_response_parse_params(struct mgcp_response *r);
+
+int mgcp_client_tx(struct mgcp_client *mgcp, struct msgb *msg,
+		   mgcp_response_cb_t response_cb, void *priv);
+int mgcp_client_cancel(struct mgcp_client *mgcp, mgcp_trans_id_t trans_id);
+
+struct msgb *mgcp_msg_gen(struct mgcp_client *mgcp, struct mgcp_msg *mgcp_msg);
+mgcp_trans_id_t mgcp_msg_trans_id(struct msgb *msg);

include/osmocom/mgcp_client/mgcp_client_pool.h

@@ -2,6 +2,8 @@
 
 #include <stdbool.h>
 
+#include <osmocom/vty/vty.h>
+
 struct mgcp_client;
 struct mgcp_client_pool;
 struct mgcp_client_pool_member;
@@ -12,6 +14,7 @@ void mgcp_client_pool_vty_init(int parent_node, int mgw_node, const char *indent
 int mgcp_client_pool_config_write(struct vty *vty, const char *indent);
 unsigned int mgcp_client_pool_connect(struct mgcp_client_pool *pool);
 void mgcp_client_pool_register_single(struct mgcp_client_pool *pool, struct mgcp_client *mgcp_client);
+bool mgcp_client_pool_empty(const struct mgcp_client_pool *pool);
 
 struct mgcp_client *mgcp_client_pool_get(struct mgcp_client_pool *pool);
 void mgcp_client_pool_put(struct mgcp_client *mgcp_client);

include/osmocom/sdp/fmtp.h

@@ -0,0 +1,33 @@
+/* Public API for codec management in SDP messages: managing SDP fmtp strings. */
+/*
+ * (C) 2024 by sysmocom - s.f.m.c. GmbH <info@sysmocom.de>
+ * All Rights Reserved.
+ *
+ * Author: Neels Janosch Hofmeyr <nhofmeyr@sysmocom.de>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ *
+ *  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 2 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/>.
+ *
+ */
+#pragma once
+
+#include <stddef.h>
+#include <stdbool.h>
+#include <stdint.h>
+
+bool osmo_sdp_fmtp_get_val(char *val, size_t val_size, const char *fmtp, const char *option_name);
+int64_t osmo_sdp_fmtp_get_int(const char *fmtp, const char *option_name, int64_t default_value);
+
+bool osmo_sdp_fmtp_amr_is_octet_aligned(const char *fmtp);

include/osmocom/sdp/sdp_strings.h

@@ -0,0 +1,36 @@
+/* Central definition of string tokens used for parsing and composing SDP messages */
+#pragma once
+
+#define OSMO_SDP_STR_MEDIA "m"
+#define OSMO_SDP_STR_ATTRIB "a"
+#define OSMO_SDP_STR_TIME_ACTIVE "t"
+
+#define OSMO_SDP_STR_RTPMAP "rtpmap"
+#define OSMO_SDP_STR_FMTP "fmtp"
+#define OSMO_SDP_STR_PTIME "ptime"
+
+/*! "a=foo:" */
+#define OSMO_SDP_A_PREFIX(STR) OSMO_SDP_STR_ATTRIB "=" STR ":"
+
+/* Media Direction Attributes "a=recvonly", "a=sendrecv", "a=sendonly", "a=inactive" RFC-8866 6.7. */
+#define OSMO_SDP_STR_RECVONLY "recvonly"
+#define OSMO_SDP_STR_SENDRECV "sendrecv"
+#define OSMO_SDP_STR_SENDONLY "sendonly"
+#define OSMO_SDP_STR_INACTIVE "inactive"
+
+/* AMR related tokens */
+
+#define OSMO_SDP_STR_AMR_OCTET_ALIGN "octet-align"
+
+/*! "octet-align=1" */
+#define OSMO_SDP_STR_AMR_OCTET_ALIGN_1  OSMO_SDP_STR_AMR_OCTET_ALIGN "=1"
+
+/*! "octet-align=0".
+ * According to spec [1], "octet-align=0" is identical to omitting 'octet-align' entirely. In Osmocom practice, whether
+ * or not "octet-align=0" is present can make a big difference for osmo-mgw versions 1.12 and older, which do not heed
+ * [1].
+ *
+ * spec [1]: RFC4867, see details in description of osmo_sdp_fmtp_amr_is_octet_aligned().
+ */
+#define OSMO_SDP_STR_AMR_OCTET_ALIGN_0  OSMO_SDP_STR_AMR_OCTET_ALIGN "=0"
+

src/Makefile.am

@@ -13,14 +13,9 @@ AM_CFLAGS = \
 	$(COVERAGE_CFLAGS) \
 	$(NULL)
 
-AM_LDFLAGS = \
-	$(LIBOSMOCORE_LIBS) \
-	$(LIBOSMOGSM_LIBS) \
-	$(COVERAGE_LDFLAGS) \
-	$(NULL)
-
 # Libraries
 SUBDIRS = \
+	libosmo-sdp \
 	libosmo-mgcp-client \
 	libosmo-mgcp \
 	$(NULL)

src/libosmo-mgcp-client/Makefile.am

@@ -14,14 +14,12 @@ AM_CFLAGS = \
 	$(NULL)
 
 AM_LDFLAGS = \
-	$(LIBOSMOCORE_LIBS) \
-	$(LIBOSMOVTY_LIBS) \
 	$(COVERAGE_LDFLAGS) \
 	$(NULL)
 
 # This is not at all related to the release version, but a range of supported
 # API versions. Read TODO_RELEASE in the source tree's root!
-MGCP_CLIENT_LIBVERSION=10:0:1
+MGCP_CLIENT_LIBVERSION=13:0:1
 
 lib_LTLIBRARIES = \
 	libosmo-mgcp-client.la \
@@ -40,3 +38,9 @@ libosmo_mgcp_client_la_LDFLAGS = \
 	-version-info $(MGCP_CLIENT_LIBVERSION) \
 	-no-undefined \
 	$(NULL)
+
+libosmo_mgcp_client_la_LIBADD = \
+	$(top_builddir)/src/libosmo-sdp/libosmo-sdp.la \
+	$(LIBOSMOCORE_LIBS) \
+	$(LIBOSMOVTY_LIBS) \
+	$(NULL)

src/libosmo-mgcp-client/mgcp_client_endpoint_fsm.c

@@ -173,6 +173,30 @@ const char *osmo_mgcpc_ep_name(const struct osmo_mgcpc_ep *ep)
 	return osmo_fsm_inst_name(ep->fi);
 }
 
+/*! Get "local endpoint name" part of the endpoint name: (local-endpoint-name@domain-name)
+ *
+ * \param ep  The MGCP Endpoint
+ * \returns the local endpoint name if found, NULL on error.
+ */
+const char *osmo_mgcpc_ep_local_name(const struct osmo_mgcpc_ep *ep)
+{
+	static char buf[1024];
+	const char *sep;
+
+	OSMO_ASSERT(ep);
+	sep = strchr(ep->endpoint, '@');
+	if (!sep) {
+		OSMO_STRLCPY_ARRAY(buf, ep->endpoint);
+		return buf;
+	}
+	if (sep - ep->endpoint >= sizeof(buf))
+		return NULL;
+
+	memcpy(buf, ep->endpoint, sep - ep->endpoint);
+	buf[sep - ep->endpoint] = '\0';
+	return buf;
+}
+
 const char *mgcp_conn_peer_name(const struct mgcp_conn_peer *info)
 {
 	/* I'd be fine with a smaller buffer and accept truncation, but gcc possibly refuses to build if
@@ -509,10 +533,42 @@ static void on_success(struct osmo_mgcpc_ep_ci *ci, void *data)
 	       mgcp_conn_peer_name(ci->got_port_info? &ci->rtp_info : NULL),
 	       ci->notify.fi ? "" : " (not sending a notification)");
 
+	/* Below ordering is a delicate decision:
+	 *
+	 * We want to
+	 * - emit the resulting event to ci->notify.fi,
+	 * - check whether we want to tx the next pending MGCP message.
+	 * Both these steps may terminate (=deallocate) the ep.
+	 * So whichever one goes first may cause a use-after-free in the other.
+	 *
+	 * When dispatching the FSM event, we don't get an rc indicating dealloc of the FSM -- it may deallocate and we
+	 * cannot tell. The common mechanism for that is osmo_fsm_set_dealloc_ctx(OTC_SELECT) and query the still
+	 * allocated FSM state after termination (here we would check 'if (ci->ep != NULL)'), but we cannot assume the
+	 * caller has actually set up an osmo_fsm_set_dealloc_ctx(). At time of writing, e.g. osmo-hnbgw does not use
+	 * it.
+	 *
+	 * In osmo_mgcpc_ep_fsm_check_state_chg_after_response(), we do get an rc: false means FSM has terminated.
+	 * On termination, the ep emits a term event to the FSM's parent.
+	 * That may cause the notify.fi to be terminated in turn, depending on how the caller set things up.
+	 * So: we cannot store notify.fi before, then call osmo_mgcpc_ep_fsm_check_state_chg_after_response(), and then
+	 * emit the event, because notify.fi may have deallocated. We cannot look up whether
+	 * osmo_mgcpc_ep_cancel_notify() has been called, because ci may have deallocated along with ci->ep.
+	 *
+	 * We have to skip emitting below success event in case the ep is now terminated.
+	 * - It may be the final DLCX OK: not a problem, osmo_mgcpc_ep_ci_dlcx() has no notify args on purpose, so we do
+	 *   make all callers not set a notify event for DLCX by design. notify.fi should always be NULL when the final
+	 *   DLCX OK terminates the local endpoint state.
+	 * - It may also be sudden termination due to a bad problem, in which case we shouldn't emit success.
+	 *   The osmo_fsm_inst.parent_term_event should suffice as feedback to the caller.
+	 */
+
+	if (osmo_mgcpc_ep_fsm_check_state_chg_after_response(ci->ep->fi) == false) {
+		/* false means, the ci->ep has been terminated. */
+		return;
+	}
+
 	if (ci->notify.fi)
 		osmo_fsm_inst_dispatch(ci->notify.fi, ci->notify.success, ci->notify.data);
-
-	osmo_mgcpc_ep_fsm_check_state_chg_after_response(ci->ep->fi);
 }
 
 /*! Return the MGW's local RTP port information for this connection, i.e. the local port that MGW is receiving on, as
@@ -662,11 +718,11 @@ void osmo_mgcpc_ep_ci_request(struct osmo_mgcpc_ep_ci *ci,
 	osmo_strlcpy(cleared_ci.mgcp_ci_str, ci->mgcp_ci_str, sizeof(cleared_ci.mgcp_ci_str));
 	*ci = cleared_ci;
 
-	LOG_CI_VERB(ci, LOGL_DEBUG, "notify=%s\n", osmo_fsm_inst_name(ci->notify.fi));
-
 	if (verb_info)
 		ci->verb_info = *verb_info;
 
+	LOG_CI_VERB(ci, LOGL_DEBUG, "notify=%s\n", osmo_fsm_inst_name(ci->notify.fi));
+
 	if (ep->endpoint[0]) {
 		if (ci->verb_info.endpoint[0] && strcmp(ci->verb_info.endpoint, ep->endpoint))
 			LOG_CI(ci, LOGL_ERROR,

src/libosmo-mgcp-client/mgcp_client_fsm.c

@@ -19,6 +19,7 @@
  */
 
 #include <osmocom/mgcp_client/mgcp_client.h>
+#include <osmocom/mgcp_client/mgcp_client_internal.h>
 #include <osmocom/mgcp_client/mgcp_client_fsm.h>
 #include <osmocom/core/utils.h>
 #include <osmocom/core/fsm.h>
@@ -114,12 +115,10 @@ static void make_crcx_msg(struct mgcp_msg *mgcp_msg, struct mgcp_conn_peer *info
 		.call_id = info->call_id,
 		.conn_mode = MGCP_CONN_RECV_ONLY,
 		.ptime = info->ptime,
-		.codecs_len = info->codecs_len,
 		.ptmap_len = info->ptmap_len,
 		.param_present = info->param_present
 	};
 	osmo_strlcpy(mgcp_msg->endpoint, info->endpoint, MGCP_ENDPOINT_MAXLEN);
-	memcpy(mgcp_msg->codecs, info->codecs, sizeof(mgcp_msg->codecs));
 	memcpy(mgcp_msg->ptmap, info->ptmap, sizeof(mgcp_msg->ptmap));
 	memcpy(&mgcp_msg->param, &info->param, sizeof(mgcp_msg->param));
 
@@ -136,10 +135,19 @@ static void make_crcx_msg(struct mgcp_msg *mgcp_msg, struct mgcp_conn_peer *info
 
 static void add_audio(struct mgcp_msg *mgcp_msg, struct mgcp_conn_peer *info)
 {
-	mgcp_msg->presence |= MGCP_MSG_PRESENCE_AUDIO_IP | MGCP_MSG_PRESENCE_AUDIO_PORT;
-	mgcp_msg->audio_ip = info->addr;
-	mgcp_msg->audio_port = info->port;
-	mgcp_msg->conn_mode = MGCP_CONN_RECV_SEND;
+	bool ip_is_set = info->addr[0] != '\0' &&
+			 strncmp(info->addr, "::", sizeof(info->addr)) != 0 &&
+			 strncmp(info->addr, "0.0.0.0", sizeof(info->addr)) != 0;
+	if (ip_is_set) {
+		mgcp_msg->presence |= MGCP_MSG_PRESENCE_AUDIO_IP;
+		mgcp_msg->audio_ip = info->addr;
+	}
+	if (info->port) {
+		mgcp_msg->presence |= MGCP_MSG_PRESENCE_AUDIO_PORT;
+		mgcp_msg->audio_port = info->port;
+	}
+	if (ip_is_set && info->port)
+		mgcp_msg->conn_mode = MGCP_CONN_RECV_SEND;
 }
 
 static void set_conn_mode(struct mgcp_msg *mgcp_msg, struct mgcp_conn_peer *peer)
@@ -163,12 +171,10 @@ static struct msgb *make_mdcx_msg(struct mgcp_ctx *mgcp_ctx)
 		.audio_ip = mgcp_ctx->conn_peer_local.addr,
 		.audio_port = mgcp_ctx->conn_peer_local.port,
 		.ptime = mgcp_ctx->conn_peer_local.ptime,
-		.codecs_len = mgcp_ctx->conn_peer_local.codecs_len,
 		.ptmap_len = mgcp_ctx->conn_peer_local.ptmap_len,
 		.param_present = mgcp_ctx->conn_peer_local.param_present
 	};
 	osmo_strlcpy(mgcp_msg.endpoint, mgcp_ctx->conn_peer_remote.endpoint, MGCP_ENDPOINT_MAXLEN);
-	memcpy(mgcp_msg.codecs, mgcp_ctx->conn_peer_local.codecs, sizeof(mgcp_msg.codecs));
 	memcpy(mgcp_msg.ptmap, mgcp_ctx->conn_peer_local.ptmap, sizeof(mgcp_msg.ptmap));
 	memcpy(&mgcp_msg.param, &mgcp_ctx->conn_peer_local.param, sizeof(mgcp_ctx->conn_peer_local.param));
 
@@ -221,8 +227,7 @@ static void fsm_crcx_cb(struct osmo_fsm_inst *fi, uint32_t event, void *data)
 			 mgcp_ctx->conn_peer_local.endpoint);
 
 		make_crcx_msg(&mgcp_msg, &mgcp_ctx->conn_peer_local);
-		if (mgcp_ctx->conn_peer_local.port)
-			add_audio(&mgcp_msg, &mgcp_ctx->conn_peer_local);
+		add_audio(&mgcp_msg, &mgcp_ctx->conn_peer_local);
 		set_conn_mode(&mgcp_msg, &mgcp_ctx->conn_peer_local);
 
 		msg = mgcp_msg_gen(mgcp_ctx->mgcp, &mgcp_msg);
@@ -364,13 +369,21 @@ static void fsm_ready_cb(struct osmo_fsm_inst *fi, uint32_t event, void *data)
 	switch (event) {
 	case EV_MDCX:
 		msg = make_mdcx_msg(mgcp_ctx);
-		OSMO_ASSERT(msg);
+		if (!msg) {
+			/* make_mdcx_msg() should already have logged the error */
+			osmo_fsm_inst_term(fi, OSMO_FSM_TERM_ERROR, NULL);
+			return;
+		}
 		rc = mgcp_client_tx(mgcp, msg, mgw_mdcx_resp_cb, fi);
 		new_state = ST_MDCX_RESP;
 		break;
 	case EV_DLCX:
 		msg = make_dlcx_msg(mgcp_ctx);
-		OSMO_ASSERT(msg);
+		if (!msg) {
+			/* make_dlcx_msg() should already have logged the error */
+			osmo_fsm_inst_term(fi, OSMO_FSM_TERM_ERROR, NULL);
+			return;
+		}
 		rc = mgcp_client_tx(mgcp, msg, mgw_dlcx_resp_cb, fi);
 		new_state = ST_DLCX_RESP;
 		break;
@@ -611,6 +624,72 @@ static struct osmo_fsm fsm_mgcp_client = {
 	.log_subsys = DLMGCP,
 };
 
+/* Provide backwards compat for deprecated conn_peer->codecs[]: when the caller passes in an mgcp_conn_peer instance
+ * that has codecs[] set, apply it to ptmap[] instead. */
+static void mgcp_conn_peer_compat(struct mgcp_conn_peer *conn_peer)
+{
+	struct ptmap ptmap[MGCP_MAX_CODECS];
+	unsigned int ptmap_len;
+
+	if (!conn_peer->codecs_len)
+		return;
+
+	/* Before dropping codecs[], codecs[] would indicate the order in which the codecs should appear in SDP. ptmap[]
+	 * would indicate payload type numbers when not using a default payload type number (may omit entries).
+	 * Now, ptmap[] just indicates both at the same time; codecs[] should be empty, and ptmap[] lists all codecs.
+	 * So if any codecs[] are present, recreate ptmap[] in the order of codecs[]. */
+
+	ptmap_len = 0;
+	for (int i = 0; i < conn_peer->codecs_len; i++) {
+		enum mgcp_codecs codec = conn_peer->codecs[i];
+		struct ptmap *found = NULL;
+
+		/* Look up whether a specific pt was indicated for this codec */
+		for (int p = 0; p < conn_peer->ptmap_len; p++) {
+			if (conn_peer->ptmap[p].codec != codec)
+				continue;
+			found = &conn_peer->ptmap[p];
+			break;
+		}
+		if (found) {
+			ptmap[ptmap_len] = *found;
+		} else {
+			ptmap[ptmap_len] = (struct ptmap){
+				.codec = codec,
+				/* some enum mgcp_codecs correspond to their standard PT nr, so for compat: */
+				.pt = codec,
+			};
+		}
+		ptmap_len++;
+	}
+
+	/* Are there any entries in the old ptmap that were omitted by codecs[]? */
+	for (int p = 0; p < conn_peer->ptmap_len; p++) {
+		bool exists = false;
+		for (int i = 0; i < ptmap_len; i++) {
+			if (ptmap_cmp(&ptmap[i], &conn_peer->ptmap[p]))
+				continue;
+			exists = true;
+			break;
+		}
+
+		if (exists)
+			continue;
+
+		if (ptmap_len >= ARRAY_SIZE(ptmap))
+			break;
+
+		/* Not present yet, add it to the end */
+		ptmap[ptmap_len] = conn_peer->ptmap[p];
+		ptmap_len++;
+	}
+
+	/* Use the new ptmap[], and clear out legacy codecs[]. */
+	memcpy(conn_peer->ptmap, ptmap, sizeof(conn_peer->ptmap));
+	conn_peer->ptmap_len = ptmap_len;
+	conn_peer->codecs_len = 0;
+}
+
 /*! allocate FSM, and create a new connection on the MGW.
  *  \param[in] mgcp MGCP client descriptor.
  *  \param[in] parent_fi Parent FSM instance.
@@ -625,6 +704,7 @@ struct osmo_fsm_inst *mgcp_conn_create(struct mgcp_client *mgcp, struct osmo_fsm
 	struct osmo_fsm_inst *fi;
 	struct in6_addr ip_test;
 
+	mgcp_conn_peer_compat(conn_peer);
 
 	OSMO_ASSERT(parent_fi);
 	OSMO_ASSERT(mgcp);
@@ -664,6 +744,8 @@ int mgcp_conn_modify(struct osmo_fsm_inst *fi, uint32_t parent_evt, struct mgcp_
 	struct mgcp_ctx *mgcp_ctx = fi->priv;
 	struct in6_addr ip_test;
 
+	mgcp_conn_peer_compat(conn_peer);
+
 	OSMO_ASSERT(mgcp_ctx);
 	OSMO_ASSERT(conn_peer);
 

src/libosmo-mgcp-client/mgcp_client_pool.c

@@ -75,6 +75,11 @@ void mgcp_client_pool_register_single(struct mgcp_client_pool *pool, struct mgcp
 	pool->mgcp_client_single = mgcp_client;
 }
 
+bool mgcp_client_pool_empty(const struct mgcp_client_pool *pool)
+{
+	return llist_empty(&pool->member_list);
+}
+
 /*! Lookup the selected MGCP client config by its reference number */
 struct mgcp_client_pool_member *mgcp_client_pool_find_member_by_nr(struct mgcp_client_pool *pool, unsigned int nr)
 {
@@ -89,7 +94,7 @@ struct mgcp_client_pool_member *mgcp_client_pool_find_member_by_nr(struct mgcp_c
 }
 
 /* Not every pool member may have a functional MGCP client, we will run through the pool once until we meet a
- * pool member that is suitable (has a client, is not blocked, has a low load). */
+ * pool member that is suitable (is not blocked, has a client with a working link, has a low load). */
 static struct mgcp_client_pool_member *mgcp_client_pool_pick(struct mgcp_client_pool *pool)
 {
 	struct mgcp_client_pool_member *pool_member;
@@ -98,14 +103,15 @@ static struct mgcp_client_pool_member *mgcp_client_pool_pick(struct mgcp_client_
 
 	llist_for_each_entry(pool_member, &pool->member_list, list) {
 		n_pool_members++;
-		if (pool_member->blocked == false && pool_member->client) {
+		bool conn_up = pool_member->client && pool_member->client->conn_up;
+		if (pool_member->blocked == false && conn_up) {
 			if (!pool_member_picked)
 				pool_member_picked = pool_member;
 			else if (pool_member_picked->refcount > pool_member->refcount)
 				pool_member_picked = pool_member;
 		} else {
-			LOGPPMGW(pool_member, LOGL_DEBUG, "%s -- MGW %u is unusable (blocked=%u, cli=%u)\n",
-				 __func__, pool_member->nr, pool_member->blocked, !!pool_member->client);
+			LOGPPMGW(pool_member, LOGL_DEBUG, "%s -- MGW %u is unusable (blocked=%u, cli=%u, link=%u)\n",
+				 __func__, pool_member->nr, pool_member->blocked, !!pool_member->client, conn_up);
 		}
 	}
 

src/libosmo-mgcp-client/mgcp_client_vty.c

@@ -1,5 +1,5 @@
 /* MGCP client interface to quagga VTY */
-/* (C) 2016 by sysmocom s.m.f.c. GmbH <info@sysmocom.de>
+/* (C) 2016 by sysmocom s.f.m.c. GmbH <info@sysmocom.de>
  * Based on OpenBSC interface to quagga VTY (libmsc/vty_interface_layer3.c)
  * (C) 2009 by Harald Welte <laforge@gnumonks.org>
  * (C) 2009-2011 by Holger Hans Peter Freyther
@@ -28,6 +28,7 @@
 #include <osmocom/vty/command.h>
 #include <osmocom/vty/misc.h>
 #include <osmocom/core/utils.h>
+#include <osmocom/core/timer.h>
 
 #include <osmocom/mgcp_client/mgcp_client.h>
 #include <osmocom/mgcp_client/mgcp_client_internal.h>
@@ -48,19 +49,43 @@ static struct mgcp_client_conf *global_mgcp_client_conf = NULL;
 /* Pointer to the MGCP pool that is managed by mgcp_client_pool_vty_init() */
 static struct mgcp_client_pool *global_mgcp_client_pool = NULL;
 
-struct mgcp_client_conf *get_mgcp_client_config(struct vty *vty)
+static struct mgcp_client_conf *get_mgcp_client_config(struct vty *vty)
 {
 	if (global_mgcp_client_pool && vty->node == global_mgcp_client_pool->vty_node->node)
 		return vty->index;
 
 	/* Global single MGCP config, deprecated: */
 	vty_out(vty, "%% MGCP commands outside of 'mgw' nodes are deprecated. "
-		"You should consider reading User Manual and migrating to 'mgw' node.%s",
+		"You should consider reading the User Manual and migrating to 'mgw' node.%s",
 		VTY_NEWLINE);
 
 	return global_mgcp_client_conf;
 }
 
+static struct mgcp_client *get_mgcp_client(struct vty *vty)
+{
+	struct mgcp_client_conf *conf = get_mgcp_client_config(vty);
+	struct mgcp_client_pool_member *pool_member;
+
+	if (global_mgcp_client_pool && vty->node == global_mgcp_client_pool->vty_node->node) {
+		llist_for_each_entry(pool_member, &global_mgcp_client_pool->member_list, list) {
+			/* Find matching the conf pointer: */
+			if (&pool_member->conf != conf)
+				continue;
+			return pool_member->client;
+		}
+	}
+
+	/* Global single MGCP config, deprecated: */
+	vty_out(vty, "%% MGCP commands outside of 'mgw' nodes are deprecated. "
+		"You should consider reading the User Manual and migrating to 'mgw' node.%s",
+		VTY_NEWLINE);
+
+	/* There's no way to obtain the struct mgcp_client in old interface, but anyway it's deprecated. */
+	return NULL;
+}
+
+
 DEFUN(cfg_mgw_local_ip, cfg_mgw_local_ip_cmd,
       "local-ip " VTY_IPV46_CMD,
       "local bind to connect to MGW from\n"
@@ -280,6 +305,91 @@ ALIAS_DEPRECATED(cfg_mgw_no_reset_ep_name,
       NO_STR MGW_STR "remove an endpoint name from the reset-endpoint list, e.g. 'rtpbridge/*'\n"
       "Endpoint name, e.g. 'rtpbridge/*' or 'ds/e1-0/s-3/su16-4'.\n")
 
+DEFUN(cfg_mgw_mgw_keepalive_req_interval,
+      cfg_mgw_mgw_keepalive_req_interval_cmd,
+      "keepalive request-interval <0-4294967295>",
+      "Monitor if the MGCP link against MGW is still usable\n"
+      "Send an MGCP command to the MGW at given interval if no other commands are sent\n"
+      "The interval at which send MGCP commands (s), 0 to disable\n")
+{
+	struct mgcp_client_conf *conf = get_mgcp_client_config(vty);
+	struct mgcp_client *mgcp = get_mgcp_client(vty);
+
+	conf->keepalive.req_interval_sec = atoi(argv[0]);
+
+	if (!mgcp)
+		return CMD_SUCCESS;
+
+	/* If client already exists, apply the change immediately if possible: */
+	mgcp->actual.keepalive.req_interval_sec = atoi(argv[0]);
+	if (mgcp->wq.bfd.fd != -1) { /* UDP MGCP socket connected */
+		if (mgcp->actual.keepalive.req_interval_sec > 0) {
+			/* Re-schedule: */
+			osmo_timer_schedule(&mgcp->keepalive_tx_timer, mgcp->actual.keepalive.req_interval_sec, 0);
+		} else {
+			if (osmo_timer_pending(&mgcp->keepalive_tx_timer))
+				osmo_timer_del(&mgcp->keepalive_tx_timer);
+			/* Assume link is UP by default, so that this MGW can be selected: */
+			mgcp->conn_up = true;
+		}
+	} /* else: wait until connect() to do first scheduling */
+
+	return CMD_SUCCESS;
+}
+
+DEFUN(cfg_mgw_mgw_keepalive_req_endpoint,
+      cfg_mgw_mgw_keepalive_req_endpoint_cmd,
+      "keepalive request-endpoint NAME",
+      "Monitor if the MGCP link against MGW is still usable\n"
+      "Use a given endpoint name when sending an MGCP command to the MGW for keepalive purposes\n"
+      "The name of the endpoint to use\n")
+{
+	struct mgcp_client_conf *conf = get_mgcp_client_config(vty);
+	struct mgcp_client *mgcp = get_mgcp_client(vty);
+
+	OSMO_STRLCPY_ARRAY(conf->keepalive.req_endpoint_name, argv[0]);
+
+	if (!mgcp)
+		return CMD_SUCCESS;
+
+	/* If client already exists, apply the change immediately if possible: */
+	OSMO_STRLCPY_ARRAY(mgcp->actual.keepalive.req_endpoint_name, argv[0]);
+
+	return CMD_SUCCESS;
+}
+
+DEFUN(cfg_mgw_mgw_keepalive_timeout,
+      cfg_mgw_mgw_keepalive_timeout_cmd,
+      "keepalive timeout <0-4294967295>",
+      "Monitor if the MGCP link against MGW is still usable\n"
+      "Consider the link to the MGW to be down after time without receiving any message from it\n"
+      "The timeout (s), 0 to disable\n")
+{
+	struct mgcp_client_conf *conf = get_mgcp_client_config(vty);
+	struct mgcp_client *mgcp = get_mgcp_client(vty);
+
+	conf->keepalive.timeout_sec = atoi(argv[0]);
+
+	if (!mgcp)
+		return CMD_SUCCESS;
+
+	/* If client already exists, apply the change immediately if possible: */
+	mgcp->actual.keepalive.timeout_sec = atoi(argv[0]);
+	if (mgcp->wq.bfd.fd != -1) { /* UDP MGCP socket connected */
+		if (mgcp->actual.keepalive.timeout_sec > 0) {
+			/* Re-schedule: */
+			osmo_timer_schedule(&mgcp->keepalive_rx_timer, mgcp->actual.keepalive.timeout_sec, 0);
+		} else {
+			if (osmo_timer_pending(&mgcp->keepalive_rx_timer))
+				osmo_timer_del(&mgcp->keepalive_rx_timer);
+			/* Assume link is UP by default, so that this MGW can be selected: */
+			mgcp->conn_up = true;
+		}
+	} /* else: wait until connect() to do first scheduling */
+
+	return CMD_SUCCESS;
+}
+
 static int config_write(struct vty *vty, const char *indent, struct mgcp_client_conf *conf)
 {
 	const char *addr;
@@ -317,6 +427,17 @@ static int config_write(struct vty *vty, const char *indent, struct mgcp_client_
 	llist_for_each_entry(reset_ep, &conf->reset_epnames, list)
 		vty_out(vty, "%s%sreset-endpoint %s%s", indent, mgw_prefix, reset_ep->name, VTY_NEWLINE);
 
+	if (conf->keepalive.req_interval_sec != 0)
+		vty_out(vty, "%s%skeepalive request-interval %u%s", indent, mgw_prefix,
+			conf->keepalive.req_interval_sec, VTY_NEWLINE);
+	if (strncmp(conf->keepalive.req_endpoint_name, MGCP_CLIENT_KEEPALIVE_DEFAULT_ENDP,
+		    sizeof(conf->keepalive.req_endpoint_name)) != 0)
+		vty_out(vty, "%s%skeepalive request-endpoint %s%s", indent,  mgw_prefix,
+			conf->keepalive.req_endpoint_name, VTY_NEWLINE);
+	if (conf->keepalive.timeout_sec != 0)
+		vty_out(vty, "%s%skeepalive timeout %u%s", indent,  mgw_prefix,
+			conf->keepalive.timeout_sec, VTY_NEWLINE);
+
 	return CMD_SUCCESS;
 }
 
@@ -347,6 +468,9 @@ static void vty_init_common(void *talloc_ctx, int node)
 	install_lib_element(node, &cfg_mgw_mgw_endpoint_domain_name_cmd);
 	install_lib_element(node, &cfg_mgw_mgw_reset_ep_name_cmd);
 	install_lib_element(node, &cfg_mgw_mgw_no_reset_ep_name_cmd);
+	install_lib_element(node, &cfg_mgw_mgw_keepalive_req_interval_cmd);
+	install_lib_element(node, &cfg_mgw_mgw_keepalive_req_endpoint_cmd);
+	install_lib_element(node, &cfg_mgw_mgw_keepalive_timeout_cmd);
 
 	osmo_fsm_vty_add_cmds();
 }
@@ -553,8 +677,13 @@ DEFUN(mgw_show, mgw_show_cmd, "show mgw-pool", SHOW_STR "Display information abo
 	}
 
 	llist_for_each_entry(pool_member, &global_mgcp_client_pool->member_list, list) {
+		const struct mgcp_client *cli = pool_member->client;
 		vty_out(vty, "%%  MGW %s%s", mgcp_client_pool_member_name(pool_member), VTY_NEWLINE);
-		vty_out(vty, "%%   mgcp-client:   %s%s", pool_member->client ? "connected" : "disconnected",
+		vty_out(vty, "%%   MGCP link:     %s,%s%s",
+			cli && cli->wq.bfd.fd != -1 ? "connected" : "disconnected",
+			cli && cli->conn_up ?
+				((cli->actual.keepalive.timeout_sec > 0) ? "UP" : "MAYBE") :
+				"DOWN",
 			VTY_NEWLINE);
 		vty_out(vty, "%%   service:       %s%s", pool_member->blocked ? "blocked" : "unblocked", VTY_NEWLINE);
 		vty_out(vty, "%%   ongoing calls: %u%s", pool_member->refcount, VTY_NEWLINE);

src/libosmo-mgcp/Makefile.am

@@ -16,24 +16,18 @@ AM_CFLAGS = \
 	$(NULL)
 
 AM_LDFLAGS = \
-	$(LIBOSMOCORE_LIBS) \
-	$(LIBOSMOGSM_LIBS) \
-	$(LIBOSMOVTY_LIBS) \
-	$(LIBOSMONETIF_LIBS) \
-	$(LIBOSMOABIS_LIBS) \
-	$(LIBOSMOTRAU_LIBS) \
 	$(COVERAGE_LDFLAGS) \
 	$(NULL)
 
-noinst_LIBRARIES = \
-	libosmo-mgcp.a \
+noinst_LTLIBRARIES = \
+	libosmo-mgcp.la \
 	$(NULL)
 
 noinst_HEADERS = \
 	g711common.h \
 	$(NULL)
 
-libosmo_mgcp_a_SOURCES = \
+libosmo_mgcp_la_SOURCES = \
 	mgcp_protocol.c \
 	mgcp_network.c \
 	mgcp_vty.c \
@@ -45,8 +39,17 @@ libosmo_mgcp_a_SOURCES = \
 	mgcp_stat.c \
 	mgcp_endp.c \
 	mgcp_trunk.c \
-	mgcp_ctrl.c \
 	mgcp_ratectr.c \
 	mgcp_e1.c \
 	mgcp_iuup.c \
 	$(NULL)
+
+libosmo_mgcp_la_LIBADD = \
+	$(top_builddir)/src/libosmo-sdp/libosmo-sdp.la \
+	$(LIBOSMOCORE_LIBS) \
+	$(LIBOSMOGSM_LIBS) \
+	$(LIBOSMOVTY_LIBS) \
+	$(LIBOSMONETIF_LIBS) \
+	$(LIBOSMOABIS_LIBS) \
+	$(LIBOSMOTRAU_LIBS) \
+	$(NULL)

src/libosmo-mgcp/mgcp_codec.c

@@ -24,6 +24,10 @@
 #include <osmocom/mgcp/mgcp_endp.h>
 #include <osmocom/mgcp/mgcp_trunk.h>
 #include <osmocom/mgcp/mgcp_codec.h>
+
+#include <osmocom/sdp/sdp_strings.h>
+#include <osmocom/sdp/fmtp.h>
+
 #include <errno.h>
 
 /* Helper function to dump codec information of a specified codec to a printable
@@ -116,9 +120,9 @@ void mgcp_codec_reset_all(struct mgcp_conn_rtp *conn)
  *  \param[out] conn related rtp-connection.
  *  \param[in] payload_type codec type id (e.g. 3 for GSM, -1 when undefined).
  *  \param[in] audio_name audio codec name, in uppercase (e.g. "GSM/8000/1").
- *  \param[in] param optional codec parameters (set to NULL when unused).
+ *  \param[in] fmtp optional codec parameters (set to NULL when unused).
  *  \returns 0 on success, -EINVAL on failure. */
-int mgcp_codec_add(struct mgcp_conn_rtp *conn, int payload_type, const char *audio_name, const struct mgcp_codec_param *param)
+int mgcp_codec_add2(struct mgcp_conn_rtp *conn, int payload_type, const char *audio_name, const char *fmtp)
 {
 	int rate;
 	int channels;
@@ -261,12 +265,16 @@ int mgcp_codec_add(struct mgcp_conn_rtp *conn, int payload_type, const char *aud
 		}
 	}
 
-	/* Copy over optional codec parameters */
-	if (param) {
-		codec->param = *param;
-		codec->param_present = true;
-	} else
-		codec->param_present = false;
+	if (fmtp) {
+		OSMO_STRLCPY_ARRAY(codec->fmtp, fmtp);
+		if (strlen(codec->fmtp) != strlen(fmtp)) {
+			LOGP(DLMGCP, LOGL_ERROR, "fmtp too long: %zu > %zu\n", strlen(fmtp), strlen(codec->fmtp));
+			/* let's just hope what is there is still useful, worst case the call's audio doesn't work */
+		}
+	}
+
+	/* legacy */
+	codec->param_present = false;
 
 	conn->end.codecs_assigned++;
 	return 0;
@@ -276,110 +284,44 @@ error:
 	return -EINVAL;
 }
 
-/* Check if the given codec is applicable on the specified endpoint
- * Helper function for mgcp_codec_decide() */
-static bool is_codec_compatible(const struct mgcp_endpoint *endp, const struct mgcp_rtp_codec *codec)
-{
-	/* A codec name must be set, if not, this might mean that the codec
-	 * (payload type) that was assigned is unknown to us so we must stop
-	 * here. */
-	if (!strlen(codec->subtype_name))
-		return false;
-
-	/* FIXME: implement meaningful checks to make sure that the given codec
-	 * is compatible with the given endpoint */
-
-	return true;
-}
-
-/*! Decide for one suitable codec
- *  \param[in] conn related rtp-connection.
+/*! Legacy compat, use mgcp_codec_add2() instead to be able to pass any fmtp besides AMR octet-align=1.
+ * Add codec configuration depending on payload type and/or codec name. This
+ *  function uses the input parameters to extrapolate the full codec information.
+ *  \param[out] codec configuration (caller provided memory).
+ *  \param[out] conn related rtp-connection.
+ *  \param[in] payload_type codec type id (e.g. 3 for GSM, -1 when undefined).
+ *  \param[in] audio_name audio codec name, in uppercase (e.g. "GSM/8000/1").
+ *  \param[in] param optional codec parameters (set to NULL when unused).
  *  \returns 0 on success, -EINVAL on failure. */
-int mgcp_codec_decide(struct mgcp_conn_rtp *conn)
+int mgcp_codec_add(struct mgcp_conn_rtp *conn, int payload_type, const char *audio_name, const struct mgcp_codec_param *param)
 {
-	struct mgcp_rtp_end *rtp;
-	unsigned int i;
-	struct mgcp_endpoint *endp;
-	bool codec_assigned = false;
+	const char *fmtp = NULL;
+	if (param && param->amr_octet_aligned_present)
+		fmtp = (param->amr_octet_aligned ? OSMO_SDP_STR_AMR_OCTET_ALIGN_1 : OSMO_SDP_STR_AMR_OCTET_ALIGN_0);
 
-	endp = conn->conn->endp;
-	rtp = &conn->end;
-
-	/* This function works on the results the SDP/LCO parser has extracted
-	 * from the MGCP message. The goal is to select a suitable codec for
-	 * the given connection. When transcoding is available, the first codec
-	 * from the codec list is taken without further checking. When
-	 * transcoding is not available, then the choice must be made more
-	 * carefully. Each codec in the list is checked until one is found that
-	 * is rated compatible. The rating is done by the helper function
-	 * is_codec_compatible(), which does the actual checking. */
-	for (i = 0; i < rtp->codecs_assigned; i++) {
-		/* When no transcoding is available, avoid codecs that would
-		 * require transcoding. */
-		if (endp->trunk->no_audio_transcoding && !is_codec_compatible(endp, &rtp->codecs[i])) {
-			LOGP(DLMGCP, LOGL_NOTICE, "transcoding not available, skipping codec: %d/%s\n",
-			     rtp->codecs[i].payload_type, rtp->codecs[i].subtype_name);
-			continue;
-		}
-
-		rtp->codec = &rtp->codecs[i];
-		codec_assigned = true;
-		break;
-	}
-
-	/* FIXME: To the reviewes: This is problematic. I do not get why we
-	 * need to reset the packet_duration_ms depending on the codec
-	 * selection. I thought it were all 20ms? Is this to address some
-	 * cornercase. (This piece of code was in the code path before,
-	 * together with the note: "TODO/XXX: Store this per codec and derive
-	 * it on use" */
-	if (codec_assigned) {
-		if (rtp->maximum_packet_time >= 0
-		    && rtp->maximum_packet_time * rtp->codec->frame_duration_den >
-		    rtp->codec->frame_duration_num * 1500)
-			rtp->packet_duration_ms = 0;
-
-		return 0;
-	}
-
-	return -EINVAL;
+	return mgcp_codec_add2(conn, payload_type, audio_name, fmtp);
 }
 
-/* Check if the codec has a specific AMR mode (octet-aligned or bandwith-efficient) set. */
-bool mgcp_codec_amr_align_mode_is_indicated(const struct mgcp_rtp_codec *codec)
-{
-	if (codec->param_present == false)
-		return false;
-	if (!codec->param.amr_octet_aligned_present)
-		return false;
-	if (strcmp(codec->subtype_name, "AMR") != 0)
-		return false;
-	return true;
-}
-
-/* Return true if octet-aligned is set in the given codec. Default to octet-aligned=0, i.e. bandwidth-efficient mode.
- * See RFC4867 "RTP Payload Format for AMR and AMR-WB" sections "8.1. AMR Media Type Registration" and "8.2. AMR-WB
- * Media Type Registration":
- *
- *    octet-align: Permissible values are 0 and 1.  If 1, octet-aligned
- *                 operation SHALL be used.  If 0 or if not present,
- *                 bandwidth-efficient operation is employed.
- *
- * https://tools.ietf.org/html/rfc4867
- */
 bool mgcp_codec_amr_is_octet_aligned(const struct mgcp_rtp_codec *codec)
 {
-	if (!codec->param_present)
-		return false;
-	if (!codec->param.amr_octet_aligned_present)
-		return false;
-	return codec->param.amr_octet_aligned;
+	/* Legacy */
+	if (!codec->fmtp[0]
+	    && codec->param_present
+	    && codec->param.amr_octet_aligned_present)
+		return codec->param.amr_octet_aligned;
+
+	return osmo_sdp_fmtp_amr_is_octet_aligned(codec->fmtp);
 }
 
-/* Compare two codecs, all parameters must match up, except for the payload type
- * number. */
+/* Compare two codecs, all parameters must match up */
 static bool codecs_same(struct mgcp_rtp_codec *codec_a, struct mgcp_rtp_codec *codec_b)
 {
+	/* All codec properties must match up, except the payload type number. Even though standardisd payload numbers
+	 * exist for certain situations, the call agent may still assign them freely. Hence we must not insist on equal
+	 * payload type numbers. Also the audio_name is not checked since it is already parsed into subtype_name, rate,
+	 * and channels, which are checked. */
+	if (strcmp(codec_a->subtype_name, codec_b->subtype_name))
+		return false;
 	if (codec_a->rate != codec_b->rate)
 		return false;
 	if (codec_a->channels != codec_b->channels)
@@ -388,61 +330,172 @@ static bool codecs_same(struct mgcp_rtp_codec *codec_a, struct mgcp_rtp_codec *c
 		return false;
 	if (codec_a->frame_duration_den != codec_b->frame_duration_den)
 		return false;
-	if (strcmp(codec_a->subtype_name, codec_b->subtype_name))
-		return false;
 
-	/* Note: AMR allows to set the RTP payload format to octet-aligned or bandwith-efficient (octet-aligned=0)
-	 * via SDP. This difference concerns payload format only, but not the actual codec. It is not a difference
-	 * within the meaning of this function. */
+	/* AMR payload may be formatted in two different payload formats, it is still the same codec but since the
+	 * formatting of the payload is different, conversation is required, so we must treat it as a different
+	 * codec here. */
+	if (strcmp(codec_a->subtype_name, "AMR") == 0) {
+		if (mgcp_codec_amr_is_octet_aligned(codec_a) != mgcp_codec_amr_is_octet_aligned(codec_b))
+			return false;
+	}
 
 	return true;
 }
 
-/*! Translate a given payload type number that belongs to the packet of a
- *  source connection to the equivalent payload type number that matches the
- *  configuration of a destination connection.
- *  \param[in] conn_src related source rtp-connection.
- *  \param[in] conn_dst related destination rtp-connection.
- *  \param[in] payload_type number from the source packet or source connection.
- *  \returns translated payload type number on success, -EINVAL on failure. */
-int mgcp_codec_pt_translate(struct mgcp_conn_rtp *conn_src, struct mgcp_conn_rtp *conn_dst, int payload_type)
+/* Compare two codecs, all parameters must match up, except parameters related to payload formatting (not checked). */
+static bool codecs_convertible(struct mgcp_rtp_codec *codec_a, struct mgcp_rtp_codec *codec_b)
 {
-	struct mgcp_rtp_end *rtp_src;
-	struct mgcp_rtp_end *rtp_dst;
-	struct mgcp_rtp_codec *codec_src = NULL;
-	struct mgcp_rtp_codec *codec_dst = NULL;
+	/* OsmoMGW currently has no ability to transcode from one codec to another. However OsmoMGW is still able to
+	 * translate between different payload formats as long as the encoded voice data itself does not change.
+	 * Therefore we must insist on equal codecs but still allow different payload formatting. */
+
+	/* In 3G IuUP, AMR may be encapsulated in IuFP, this means even though the codec name and negotiated rate is
+	 * different, the formatting can still be converted by OsmoMGW. Therefore we won't insist on equal
+	 * subtype_name and rate if we detect IuFP and AMR is used on the same tandem. */
+	if (strcmp(codec_a->subtype_name, "AMR") == 0 && strcmp(codec_b->subtype_name, "VND.3GPP.IUFP") == 0)
+		goto iufp;
+	if (strcmp(codec_a->subtype_name, "VND.3GPP.IUFP") == 0 && strcmp(codec_b->subtype_name, "AMR") == 0)
+		goto iufp;
+
+	if (strcmp(codec_a->subtype_name, codec_b->subtype_name))
+		return false;
+	if (codec_a->rate != codec_b->rate)
+		return false;
+iufp:
+	if (codec_a->channels != codec_b->channels)
+		return false;
+	if (codec_a->frame_duration_num != codec_b->frame_duration_num)
+		return false;
+	if (codec_a->frame_duration_den != codec_b->frame_duration_den)
+		return false;
+
+	return true;
+}
+
+struct mgcp_rtp_codec *mgcp_codec_find_same(struct mgcp_conn_rtp *conn, struct mgcp_rtp_codec *codec)
+{
+	struct mgcp_rtp_end *rtp_end;
 	unsigned int i;
 	unsigned int codecs_assigned;
 
-	rtp_src = &conn_src->end;
-	rtp_dst = &conn_dst->end;
+	rtp_end = &conn->end;
 
-	/* Find the codec information that is used on the source side */
-	codecs_assigned = rtp_src->codecs_assigned;
+	/* Use the codec information from the source and try to find the equivalent of it on the destination side. In
+	 * the first run we will look for an exact match. */
+	codecs_assigned = rtp_end->codecs_assigned;
 	OSMO_ASSERT(codecs_assigned <= MGCP_MAX_CODECS);
 	for (i = 0; i < codecs_assigned; i++) {
-		if (payload_type == rtp_src->codecs[i].payload_type) {
-			codec_src = &rtp_src->codecs[i];
+		if (codecs_same(codec, &rtp_end->codecs[i])) {
+			return &rtp_end->codecs[i];
 			break;
 		}
 	}
-	if (!codec_src)
-		return -EINVAL;
 
-	/* Use the codec information from the source and try to find the
-	 * equivalent of it on the destination side */
-	codecs_assigned = rtp_dst->codecs_assigned;
+	return NULL;
+}
+
+/* For a given codec, find a convertible codec in the given connection. */
+static struct mgcp_rtp_codec *codec_find_convertible(struct mgcp_conn_rtp *conn, struct mgcp_rtp_codec *codec)
+{
+	struct mgcp_rtp_end *rtp_end;
+	unsigned int i;
+	unsigned int codecs_assigned;
+	struct mgcp_rtp_codec *codec_convertible = NULL;
+
+	rtp_end = &conn->end;
+
+	/* Use the codec information from the source and try to find the equivalent of it on the destination side. In
+	 * the first run we will look for an exact match. */
+	codec_convertible = mgcp_codec_find_same(conn, codec);
+	if (codec_convertible)
+		return codec_convertible;
+
+	/* In case we weren't able to find an exact match, we will try to find a match that is the same codec, but the
+	 * payload format may be different. This alternative will require a frame format conversion (i.e. AMR bwe->oe) */
+	codecs_assigned = rtp_end->codecs_assigned;
 	OSMO_ASSERT(codecs_assigned <= MGCP_MAX_CODECS);
 	for (i = 0; i < codecs_assigned; i++) {
-		if (codecs_same(codec_src, &rtp_dst->codecs[i])) {
-			codec_dst = &rtp_dst->codecs[i];
+		if (codecs_convertible(codec, &rtp_end->codecs[i])) {
+			codec_convertible = &rtp_end->codecs[i];
 			break;
 		}
 	}
-	if (!codec_dst)
+
+	return codec_convertible;
+}
+
+/*! Decide for one suitable codec on both of the given connections. In case a destination connection is not available,
+ *  a tentative decision is made.
+ *  \param[inout] conn_src related rtp-connection.
+ *  \param[inout] conn_dst related destination rtp-connection (NULL if not present).
+ *  \returns 0 on success, -EINVAL on failure. */
+int mgcp_codec_decide(struct mgcp_conn_rtp *conn_src, struct mgcp_conn_rtp *conn_dst)
+{
+	unsigned int i;
+
+	/* In case no destination connection is available (yet), or in case the destination connection exists but has
+	 * no codecs assigned, we are forced to make a simple tentative decision:
+	 * We just use the first codec of the source connection (conn_src) */
+	OSMO_ASSERT(conn_src->end.codecs_assigned <= MGCP_MAX_CODECS);
+	if (!conn_dst || conn_dst->end.codecs_assigned == 0) {
+		if (conn_src->end.codecs_assigned >= 1) {
+			conn_src->end.codec = &conn_src->end.codecs[0];
+			return 0;
+		} else
+			return -EINVAL;
+	}
+
+	/* Compare all codecs of the source connection (conn_src) to the codecs of the destination connection (conn_dst). In case
+	 * of a match set this codec on both connections. This would be an ideal selection since no codec conversion would be
+	 * required. */
+	for (i = 0; i < conn_src->end.codecs_assigned; i++) {
+		struct mgcp_rtp_codec *codec_conn_src = &conn_src->end.codecs[i];
+		struct mgcp_rtp_codec *codec_conn_dst = mgcp_codec_find_same(conn_dst, codec_conn_src);
+		if (codec_conn_dst) {
+			/* We found the a codec that is exactly the same (same codec, same payload format etc.) on both
+			 * sides. We now set this codec on both connections. */
+			conn_dst->end.codec = codec_conn_dst;
+			conn_src->end.codec = codec_conn_src;
+			return 0;
+		}
+	}
+
+	/* In case we could not find a codec that is exactly the same, let's at least try to find a codec that we are able
+	 * to convert. */
+	for (i = 0; i < conn_src->end.codecs_assigned; i++) {
+		struct mgcp_rtp_codec *codec_conn_src = &conn_src->end.codecs[i];
+		struct mgcp_rtp_codec *codec_conn_dst = codec_find_convertible(conn_dst, codec_conn_src);
+		if (codec_conn_dst) {
+			/* We found the a codec that we can convert to. Set each side to its codec. */
+			conn_dst->end.codec = codec_conn_dst;
+			conn_src->end.codec = codec_conn_src;
+			return 0;
+		}
+	}
+
+	if (conn_dst->end.codecs_assigned)
+		conn_dst->end.codec = &conn_dst->end.codecs[0];
+	else
 		return -EINVAL;
 
-	return codec_dst->payload_type;
+	if (conn_src->end.codecs_assigned)
+		conn_src->end.codec = &conn_src->end.codecs[0];
+	else
+		return -EINVAL;
+
+	return 0;
+}
+
+/* Check if the codec has a specific AMR mode (octet-aligned or bandwith-efficient) set. */
+bool mgcp_codec_amr_align_mode_is_indicated(const struct mgcp_rtp_codec *codec)
+{
+	if (!codec->fmtp[0]) {
+		/* Legacy */
+		return codec->param_present && codec->param.amr_octet_aligned_present;
+	}
+
+	/* Just check for presence, not the actual value. */
+	return osmo_sdp_fmtp_get_val(NULL, 0, codec->fmtp, OSMO_SDP_STR_AMR_OCTET_ALIGN);
 }
 
 /* Find the payload type number configured for a specific codec by SDP.
@@ -452,8 +505,7 @@ int mgcp_codec_pt_translate(struct mgcp_conn_rtp *conn_src, struct mgcp_conn_rtp
  * \param subtype_name  SDP codec name without parameters (e.g. "AMR").
  * \param match_nr  Index for the match found, first being match_nr == 0. Iterate all matches by calling multiple times
  *                  with incrementing match_nr.
- * \return codec definition for that conn matching the subtype_name, or NULL if no such match_nr is found.
- */
+ * \return codec definition for that conn matching the subtype_name, or NULL if no such match_nr is found. */
 const struct mgcp_rtp_codec *mgcp_codec_pt_find_by_subtype_name(struct mgcp_conn_rtp *conn,
 								const char *subtype_name, unsigned int match_nr)
 {
@@ -469,3 +521,26 @@ const struct mgcp_rtp_codec *mgcp_codec_pt_find_by_subtype_name(struct mgcp_conn
 	}
 	return NULL;
 }
+
+/*! Lookup a codec that is assigned to a connection by its payload type number.
+ *  \param[in] conn related rtp-connection.
+ *  \param[in] payload_type number of the codec to look up.
+ *  \returns pointer to codec struct on success, NULL on failure. */
+struct mgcp_rtp_codec *mgcp_codec_from_pt(struct mgcp_conn_rtp *conn, int payload_type)
+{
+	struct mgcp_rtp_end *rtp_end = &conn->end;
+	unsigned int codecs_assigned = rtp_end->codecs_assigned;
+	struct mgcp_rtp_codec *codec = NULL;
+	size_t i;
+
+	OSMO_ASSERT(codecs_assigned <= MGCP_MAX_CODECS);
+
+	for (i = 0; i < codecs_assigned; i++) {
+		if (payload_type == rtp_end->codecs[i].payload_type) {
+			codec = &rtp_end->codecs[i];
+			break;
+		}
+	}
+
+	return codec;
+}

src/libosmo-mgcp/mgcp_conn.c

@@ -110,8 +110,6 @@ static int mgcp_rtp_conn_init(struct mgcp_conn_rtp *conn_rtp, struct mgcp_conn *
 	end->rtcp.fd = -1;
 	memset(&end->addr, 0, sizeof(end->addr));
 	end->rtcp_port = 0;
-	talloc_free(end->fmtp_extra);
-	end->fmtp_extra = NULL;
 
 	/* Set default values */
 	end->frames_per_packet = 0;	/* unknown */
@@ -173,8 +171,8 @@ struct mgcp_conn *mgcp_conn_alloc(void *ctx, struct mgcp_endpoint *endp,
 	struct mgcp_conn *conn;
 	int rc;
 
-	/* Do not allow more then two connections */
-	if (llist_count(&endp->conns) >= endp->type->max_conns)
+	/* Do not allow more than the maximum number of connections */
+	if (endp->type->max_conns > 0 && llist_count(&endp->conns) >= endp->type->max_conns)
 		return NULL;
 
 	/* Create new connection and add it to the list */
@@ -358,53 +356,37 @@ char *mgcp_conn_dump(struct mgcp_conn *conn)
 {
 	static char str[sizeof(conn->name)+sizeof(conn->id)+256];
 	char ipbuf[INET6_ADDRSTRLEN];
+	struct osmo_strbuf sb = { .buf = str, .len = sizeof(str) };
 
-	if (!conn) {
-		snprintf(str, sizeof(str), "(null connection)");
-		return str;
-	}
+	if (!conn)
+		return "NULL";
 
 	switch (conn->type) {
 	case MGCP_CONN_TYPE_RTP:
+		OSMO_STRBUF_PRINTF(sb, "(%s/%s C:%s r=%s:%u<->l=%s:%u",
+				   conn->name,
+				   mgcp_conn_rtp_type_name(conn->type),
+				   conn->id,
+				   osmo_sockaddr_ntop(&conn->u.rtp.end.addr.u.sa, ipbuf) ? : "NULL",
+				   osmo_sockaddr_port(&conn->u.rtp.end.addr.u.sa),
+				   conn->u.rtp.end.local_addr ? : "NULL",
+				   conn->u.rtp.end.local_port);
+
 		switch (conn->u.rtp.type) {
-		case MGCP_RTP_DEFAULT:
-			/* Dump RTP connection */
-			snprintf(str, sizeof(str), "(%s/rtp, id:0x%s, ip:%s, "
-				"rtp:%u rtcp:%u)",
-				conn->name, conn->id,
-				osmo_sockaddr_ntop(&conn->u.rtp.end.addr.u.sa, ipbuf),
-				osmo_sockaddr_port(&conn->u.rtp.end.addr.u.sa),
-				ntohs(conn->u.rtp.end.rtcp_port));
-			break;
 		case MGCP_RTP_OSMUX:
-			snprintf(str, sizeof(str), "(%s/osmux, id:0x%s, ip:%s, "
-				"port:%u CID:%u)",
-				conn->name, conn->id,
-				osmo_sockaddr_ntop(&conn->u.rtp.end.addr.u.sa, ipbuf),
-				osmo_sockaddr_port(&conn->u.rtp.end.addr.u.sa),
-				conn->u.rtp.osmux.local_cid);
-			break;
-		case MGCP_RTP_IUUP:
-			snprintf(str, sizeof(str), "(%s/iuup, id:0x%s, ip:%s, "
-				"port:%u)",
-				conn->name, conn->id,
-				osmo_sockaddr_ntop(&conn->u.rtp.end.addr.u.sa, ipbuf),
-				osmo_sockaddr_port(&conn->u.rtp.end.addr.u.sa));
+			OSMO_STRBUF_PRINTF(sb, " CID=%u", conn->u.rtp.osmux.local_cid);
 			break;
 		default:
-			/* Should not happen, we should be able to dump
-			 * every possible connection type. */
-			snprintf(str, sizeof(str), "(unknown conn_rtp connection type %u)",
-				 conn->u.rtp.type);
 			break;
 		}
+
+		OSMO_STRBUF_PRINTF(sb, ")");
 		break;
 
 	default:
 		/* Should not happen, we should be able to dump
 		 * every possible connection type. */
-		snprintf(str, sizeof(str), "(unknown connection type)");
-		break;
+		return "(unknown connection type)";
 	}
 
 	return str;
@@ -441,3 +423,10 @@ struct mgcp_conn *mgcp_conn_get_oldest(struct mgcp_endpoint *endp)
 
 	return llist_last_entry(&endp->conns, struct mgcp_conn, entry);
 }
+
+const struct value_string mgcp_conn_rtp_type_names[] = {
+	{ MGCP_RTP_DEFAULT, "rtp" },
+	{ MGCP_RTP_OSMUX, "osmux" },
+	{ MGCP_RTP_IUUP, "iuup" },
+	{}
+};

src/libosmo-mgcp/mgcp_ctrl.c

@@ -1,36 +0,0 @@
-/*
- * (C) 2020 by Harald Welte <laforge@gnumonks.org>
- * 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 <osmocom/ctrl/control_if.h>
-#include <osmocom/mgcp/mgcp.h>
-
-
-static int mgw_ctrl_node_lookup(void *data, vector vline, int *node_type,
-				void **node_data, int *i)
-{
-	return 0;
-}
-
-
-struct ctrl_handle *mgw_ctrl_interface_setup(struct mgcp_config *cfg,
-					     const char *bind_addr, uint16_t port)
-{
-	return ctrl_interface_setup_dynip2(cfg, bind_addr, port, mgw_ctrl_node_lookup,
-					   _LAST_CTRL_NODE);
-}

src/libosmo-mgcp/mgcp_e1.c

@@ -222,7 +222,7 @@ static void e1_i460_mux_empty_cb(struct osmo_i460_subchan *schan, void *user_dat
 	osmo_i460_mux_enqueue(endp->e1.schan, msg);
 }
 
-/* called by I.460 de-multeiplexer; feed output of I.460 demux into TRAU frame sync */
+/* called by I.460 de-multiplexer; feed output of I.460 demux into TRAU frame sync */
 static void e1_i460_demux_bits_cb(struct osmo_i460_subchan *schan, void *user_data, const ubit_t *bits,
 				  unsigned int num_bits)
 {
@@ -309,8 +309,8 @@ skip:
 	return;
 }
 
-/* Function to handle outgoing E1 traffic */
-static void e1_send(struct e1inp_ts *ts, struct mgcp_trunk *trunk)
+/* handle outgoing E1 traffic */
+static void e1_send_ts_frame(struct e1inp_ts *ts, struct mgcp_trunk *trunk)
 {
 	struct msgb *msg = msgb_alloc_c(trunk, E1_TS_BYTES, "E1-TX-timeslot-bytes");
 	uint8_t *ptr;
@@ -359,19 +359,17 @@ static void e1_recv_cb(struct e1inp_ts *ts, struct msgb *msg)
 	osmo_i460_demux_in(&trunk->e1.i460_ts[ts->num - 1], msgb_data(msg), msgb_length(msg));
 
 	/* Trigger sending of pending E1 traffic */
-	e1_send(ts, trunk);
+	e1_send_ts_frame(ts, trunk);
 
-	/* e1inp_rx_ts() does not free() msgb */
+	/* e1inp_rx_ts(), the caller of this callback does not free() msgb. */
 	msgb_free(msg);
 }
 
-static int e1_init(struct mgcp_trunk *trunk, uint8_t ts_nr)
+static int e1_open(struct mgcp_trunk *trunk, uint8_t ts_nr)
 {
-	/*! Each timeslot needs only to be configured once. The Timeslot then
-	 *  stays open and permanently receives data. It is then up to the
-	 *  I.460 demultiplexer to add/remove subchannels as needed. It is
-	 *  allowed to call this function multiple times since we check if the
-	 *  timeslot is already configured. */
+	/*! One E1 timeslot may serve multiple I.460 subslots. The timeslot is opened as soon as an I.460 subslot is
+	 *  opened and will stay open until the last I.460 subslot is closed (see e1_close below). This function must
+	 *  be called any time a new I.460 subslot is opened in order to maintain constancy of the ts_usecount counter. */
 
 	struct e1inp_line *e1_line;
 	int rc;
@@ -379,12 +377,14 @@ static int e1_init(struct mgcp_trunk *trunk, uint8_t ts_nr)
 	OSMO_ASSERT(ts_nr > 0 || ts_nr < NUM_E1_TS);
 	cfg = trunk->cfg;
 
-	if (trunk->e1.ts_in_use[ts_nr - 1]) {
-		LOGPTRUNK(trunk, DE1, LOGL_INFO, "E1 timeslot %u already set up, skipping...\n", ts_nr);
+	if (trunk->e1.ts_usecount[ts_nr - 1] > 0) {
+		LOGPTRUNK(trunk, DE1, LOGL_INFO, "E1 timeslot %u already set up and in use by %u subslot(s), using it as it is...\n",
+			  ts_nr, trunk->e1.ts_usecount[ts_nr - 1]);
+		trunk->e1.ts_usecount[ts_nr - 1]++;
 		return 0;
 	}
 
-	/* Get E1 line */
+	/* Find E1 line */
 	e1_line = e1inp_line_find(trunk->e1.vty_line_nr);
 	if (!e1_line) {
 		LOGPTRUNK(trunk, DE1, LOGL_ERROR, "no such E1 line %u - check VTY config!\n",
@@ -401,12 +401,61 @@ static int e1_init(struct mgcp_trunk *trunk, uint8_t ts_nr)
 	}
 	rc = e1inp_line_update(e1_line);
 	if (rc < 0) {
-		LOGPTRUNK(trunk, DE1, LOGL_ERROR, "failed to update E1 timeslot %u.\n", ts_nr);
+		LOGPTRUNK(trunk, DE1, LOGL_ERROR, "failed to update E1 line %u.\n", ts_nr);
 		return -EINVAL;
 	}
 
 	LOGPTRUNK(trunk, DE1, LOGL_INFO, "E1 timeslot %u set up successfully.\n", ts_nr);
-	trunk->e1.ts_in_use[ts_nr - 1] = true;
+	trunk->e1.ts_usecount[ts_nr - 1]++;
+	OSMO_ASSERT(trunk->e1.ts_usecount[ts_nr - 1] == 1);
+
+	return 0;
+}
+
+static int e1_close(struct mgcp_trunk *trunk, uint8_t ts_nr)
+{
+	/* See also comment above (e1_open). This function must be called any time an I.460 subslot is closed */
+
+	struct e1inp_line *e1_line;
+	int rc;
+
+	OSMO_ASSERT(ts_nr > 0 || ts_nr < NUM_E1_TS);
+	cfg = trunk->cfg;
+
+	if (trunk->e1.ts_usecount[ts_nr - 1] > 1) {
+		trunk->e1.ts_usecount[ts_nr - 1]--;
+		LOGPTRUNK(trunk, DE1, LOGL_INFO, "E1 timeslot %u still in use by %u other subslot(s), leaving it open...\n",
+			  ts_nr, trunk->e1.ts_usecount[ts_nr - 1]);
+		return 0;
+	} else if (trunk->e1.ts_usecount[ts_nr - 1] == 0) {
+		/* This should not be as it means we close the timeslot too often. */
+		LOGPTRUNK(trunk, DE1, LOGL_ERROR, "E1 timeslot %u already closed, leaving it as it is...\n", ts_nr);
+		return -EINVAL;
+	}
+
+	/* Find E1 line */
+	e1_line = e1inp_line_find(trunk->e1.vty_line_nr);
+	if (!e1_line) {
+		LOGPTRUNK(trunk, DE1, LOGL_ERROR, "no such E1 line %u - check VTY config!\n",
+			  trunk->e1.vty_line_nr);
+		return -EINVAL;
+	}
+
+	/* Release E1 timeslot */
+	rc = e1inp_ts_config_none(&e1_line->ts[ts_nr - 1], e1_line);
+	if (rc < 0) {
+		LOGPTRUNK(trunk, DE1, LOGL_ERROR, "failed to disable E1 timeslot %u.\n", ts_nr);
+		return -EINVAL;
+	}
+	rc = e1inp_line_update(e1_line);
+	if (rc < 0) {
+		LOGPTRUNK(trunk, DE1, LOGL_ERROR, "failed to update E1 line %u.\n", trunk->e1.vty_line_nr);
+		return -EINVAL;
+	}
+
+	LOGPTRUNK(trunk, DE1, LOGL_INFO, "E1 timeslot %u closed.\n", ts_nr);
+	trunk->e1.ts_usecount[ts_nr - 1]--;
+	OSMO_ASSERT(trunk->e1.ts_usecount[ts_nr - 1] == 0);
 
 	return 0;
 }
@@ -496,7 +545,7 @@ static bool tf_type_is_amr(enum osmo_trau_frame_type ft)
 	}
 }
 
-/*! Equip E1 endpoint with I.460 mux resources.
+/*! Equip E1 endpoint with I.460 mux and E1 timeslot resources.
  *  \param[in] endp endpoint to equip
  *  \param[in] ts E1 timeslot number.
  *  \param[in] ss E1 subslot number.
@@ -517,7 +566,7 @@ int mgcp_e1_endp_equip(struct mgcp_endpoint *endp, uint8_t ts, uint8_t ss, uint8
 	endp->e1.last_amr_ft = AMR_4_75;
 
 	/* Set up E1 line / timeslot */
-	rc = e1_init(endp->trunk, ts);
+	rc = e1_open(endp->trunk, ts);
 	if (rc != 0)
 		return -EINVAL;
 
@@ -604,9 +653,15 @@ void mgcp_e1_endp_update(struct mgcp_endpoint *endp)
 }
 
 /*! Remove E1 resources from endpoint
- *  \param[in] endp endpoint to release. */
-void mgcp_e1_endp_release(struct mgcp_endpoint *endp)
+ *  \param[in] endp endpoint to release.
+ *  \param[in] ts E1 timeslot number. */
+void mgcp_e1_endp_release(struct mgcp_endpoint *endp, uint8_t ts)
 {
+	/* Guard against multiple calls. In case we don't see a subchannel anymore we can safely assume that all work
+	 * is done. */
+	if (!(endp->e1.schan || endp->e1.trau_rtp_st || endp->e1.trau_sync_fi))
+		return;
+
 	LOGPENDP(endp, DE1, LOGL_DEBUG, "removing I.460 subchannel and sync...\n");
 
 	if (endp->e1.schan)
@@ -615,8 +670,10 @@ void mgcp_e1_endp_release(struct mgcp_endpoint *endp)
 		talloc_free(endp->e1.trau_rtp_st);
 	if (endp->e1.trau_sync_fi)
 		osmo_fsm_inst_term(endp->e1.trau_sync_fi, OSMO_FSM_TERM_REGULAR, NULL);
-
 	memset(&endp->e1, 0, sizeof(endp->e1));
+
+	/* Close E1 timeslot */
+	e1_close(endp->trunk, ts);
 }
 
 /*! Accept RTP message buffer with RTP data and enqueue voice data for E1 transmit.

src/libosmo-mgcp/mgcp_endp.c

@@ -38,7 +38,6 @@
 const struct mgcp_endpoint_typeset ep_typeset = {
 	/* Specify endpoint properties for RTP endpoint */
 	.rtp = {
-		.max_conns = 2,
 		.dispatch_rtp_cb = mgcp_dispatch_rtp_bridge_cb,
 		.cleanup_cb = mgcp_cleanup_rtp_bridge_cb,
 	},
@@ -110,36 +109,6 @@ struct mgcp_endpoint *mgcp_endp_alloc(struct mgcp_trunk *trunk,
 	return endp;
 }
 
-/*! release endpoint, all open connections are closed.
- *  \param[in] endp endpoint to release */
-void mgcp_endp_release(struct mgcp_endpoint *endp)
-{
-	LOGPENDP(endp, DLMGCP, LOGL_DEBUG, "Releasing endpoint\n");
-
-	/* Normally this function should only be called when
-	 * all connections have been removed already. In case
-	 * that there are still connections open (e.g. when
-	 * RSIP is executed), free them all at once. */
-	mgcp_conn_free_all(endp);
-
-	/* We must only decrement the stat item when the endpoint as actually
-	 * claimed. An endpoint is claimed when a call-id is set */
-	if (endp->callid)
-		osmo_stat_item_dec(osmo_stat_item_group_get_item(endp->trunk->stats.common,
-								 TRUNK_STAT_ENDPOINTS_USED), 1);
-
-	/* Reset endpoint parameters and states */
-	talloc_free(endp->callid);
-	endp->callid = NULL;
-	talloc_free(endp->local_options.string);
-	endp->local_options.string = NULL;
-	talloc_free(endp->local_options.codec);
-	endp->local_options.codec = NULL;
-
-	if (endp->trunk->trunk_type == MGCP_TRUNK_E1)
-		mgcp_e1_endp_release(endp);
-}
-
 /* Check if the endpoint name contains the prefix (e.g. "rtpbridge/" or
  * "ds/e1-") and write the epname without the prefix back to the memory
  * pointed at by epname. (per trunk the prefix is the same for all endpoints,
@@ -187,7 +156,6 @@ static void chop_epname_suffix(char *epname, const struct mgcp_trunk *trunk)
 	}
 }
 
-
  /*! Convert all characters in epname to lowercase and strip trunk prefix and
  * endpoint name suffix (domain name) from epname. The result is written to
  * to the memory pointed at by epname_stripped. The expected size of the
@@ -260,6 +228,17 @@ bool mgcp_endp_is_wildcarded(const char *epname)
 	return false;
 }
 
+/*! Check if the given epname refers to a "null" endpoint.
+ *  \param[in] epname endpoint name to check
+ *  \returns true if epname refers to "null"" endpoint, else false. */
+bool mgcp_endp_is_null(const char *epname)
+{
+	if (strncasecmp(epname, "null@", 5) == 0)
+		return true;
+
+	return false;
+}
+
 /*! Find an endpoint by its name on a specified trunk.
  *  \param[out] cause pointer to store cause code, can be NULL.
  *  \param[in] epname endpoint name to lookup.
@@ -675,3 +654,36 @@ void mgcp_endp_remove_conn(struct mgcp_endpoint *endp, struct mgcp_conn *conn)
 	if (llist_empty(&endp->conns))
 		mgcp_endp_release(endp);
 }
+
+/*! release endpoint, all open connections are closed.
+ *  \param[in] endp endpoint to release */
+void mgcp_endp_release(struct mgcp_endpoint *endp)
+{
+	LOGPENDP(endp, DLMGCP, LOGL_DEBUG, "Releasing endpoint\n");
+
+	/* Normally this function should only be called when
+	 * all connections have been removed already. In case
+	 * that there are still connections open (e.g. when
+	 * RSIP is executed), free them all at once. */
+	mgcp_conn_free_all(endp);
+
+	/* We must only decrement the stat item when the endpoint as actually
+	 * claimed. An endpoint is claimed when a call-id is set */
+	if (endp->callid)
+		osmo_stat_item_dec(osmo_stat_item_group_get_item(endp->trunk->stats.common,
+								 TRUNK_STAT_ENDPOINTS_USED), 1);
+
+	/* Reset endpoint parameters and states */
+	talloc_free(endp->callid);
+	endp->callid = NULL;
+	talloc_free(endp->local_options.string);
+	endp->local_options.string = NULL;
+	talloc_free(endp->local_options.codec);
+	endp->local_options.codec = NULL;
+
+	if (endp->trunk->trunk_type == MGCP_TRUNK_E1) {
+		uint8_t ts = e1_ts_nr_from_epname(endp->name);
+		mgcp_e1_endp_release(endp, ts);
+	}
+}
+

src/libosmo-mgcp/mgcp_iuup.c

@@ -672,7 +672,7 @@ int mgcp_conn_iuup_send_rtp(struct mgcp_conn_rtp *conn_src_rtp, struct mgcp_conn
 				     "Bridge RTP=>IuUP: too short for AMR OA hdr (%u)\n", msgb_length(msg));
 			goto free_ret;
 		}
-		if (amr_hdr->ft >= AMR_FT_MAX) {
+		if (!osmo_amr_ft_valid(amr_hdr->ft)) {
 			LOG_CONN_RTP(conn_src_rtp, LOGL_NOTICE, "Bridge RTP=>IuUP: wrong AMR OA ft=%u\n", amr_hdr->ft);
 			goto free_ret;
 		}
@@ -695,7 +695,7 @@ int mgcp_conn_iuup_send_rtp(struct mgcp_conn_rtp *conn_src_rtp, struct mgcp_conn
 			goto free_ret;
 		}
 		ft = ((amr_bwe_hdr[0] & 0x07) << 1) | ((amr_bwe_hdr[1] & 0x80) >> 7);
-		if (ft >= AMR_FT_MAX) {
+		if (!osmo_amr_ft_valid(ft)) {
 			LOG_CONN_RTP(conn_src_rtp, LOGL_NOTICE, "Bridge RTP=>IuUP: wrong AMR BE ft=%u\n", ft);
 			goto free_ret;
 		}

src/libosmo-mgcp/mgcp_msg.c

@@ -75,7 +75,7 @@ void mgcp_disp_msg(unsigned char *message, unsigned int len, char *preamble)
 }
 
 /*! Parse connection mode.
- *  \param[in] mode as string (recvonly, sendrecv, sendonly or loopback)
+ *  \param[in] mode as string (recvonly, sendrecv, sendonly confecho or loopback)
  *  \param[in] endp pointer to endpoint (only used for log output)
  *  \param[out] associated connection to be modified accordingly
  *  \returns 0 on success, -1 on error */
@@ -100,6 +100,8 @@ int mgcp_parse_conn_mode(const char *mode, struct mgcp_endpoint *endp,
 		conn->mode = MGCP_CONN_RECV_SEND;
 	else if (strcasecmp(mode, "sendonly") == 0)
 		conn->mode = MGCP_CONN_SEND_ONLY;
+	else if (strcasecmp(mode, "confecho") == 0)
+		conn->mode = MGCP_CONN_CONFECHO;
 	else if (strcasecmp(mode, "loopback") == 0)
 		conn->mode = MGCP_CONN_LOOPBACK;
 	else {

src/libosmo-mgcp/mgcp_network.c

@@ -429,18 +429,6 @@ int mgcp_setup_rtp_processing_default(struct mgcp_endpoint *endp,
 	return 0;
 }
 
-void mgcp_get_net_downlink_format_default(struct mgcp_endpoint *endp,
-					  const struct mgcp_rtp_codec **codec,
-					  const char **fmtp_extra,
-					  struct mgcp_conn_rtp *conn)
-{
-	LOGPENDP(endp, DRTP, LOGL_DEBUG, "conn:%s using format defaults\n",
-		 mgcp_conn_dump(conn->conn));
-
-	*codec = conn->end.codec;
-	*fmtp_extra = conn->end.fmtp_extra;
-}
-
 void mgcp_rtp_annex_count(const struct mgcp_endpoint *endp,
 			  struct mgcp_rtp_state *state, const uint16_t seq,
 			  const int32_t transit, const uint32_t ssrc,
@@ -492,28 +480,24 @@ void mgcp_rtp_annex_count(const struct mgcp_endpoint *endp,
 
 /* There may be different payload type numbers negotiated for two connections.
  * Patch the payload type of an RTP packet so that it uses the payload type
- * that is valid for the destination connection (conn_dst) */
-static int mgcp_patch_pt(struct mgcp_conn_rtp *conn_src,
-			 struct mgcp_conn_rtp *conn_dst, struct msgb *msg)
+ * of the codec that is set for the destination connection (conn_dst) */
+static int mgcp_patch_pt(struct mgcp_conn_rtp *conn_dst, struct msgb *msg)
 {
 	struct rtp_hdr *rtp_hdr;
-	uint8_t pt_in;
-	int pt_out;
 
 	if (msgb_length(msg) < sizeof(struct rtp_hdr)) {
-		LOG_CONN_RTP(conn_src, LOGL_ERROR, "RTP packet too short (%u < %zu)\n",
+		LOG_CONN_RTP(conn_dst, LOGL_NOTICE, "RTP packet too short (%u < %zu)\n",
 			     msgb_length(msg), sizeof(struct rtp_hdr));
 		return -EINVAL;
 	}
-
 	rtp_hdr = (struct rtp_hdr *)msgb_data(msg);
 
-	pt_in = rtp_hdr->payload_type;
-	pt_out = mgcp_codec_pt_translate(conn_src, conn_dst, pt_in);
-	if (pt_out < 0)
+	if (!conn_dst->end.codec) {
+		LOG_CONN_RTP(conn_dst, LOGL_NOTICE, "no codec set on destination connection!\n");
 		return -EINVAL;
+	}
+	rtp_hdr->payload_type = (uint8_t) conn_dst->end.codec->payload_type;
 
-	rtp_hdr->payload_type = (uint8_t) pt_out;
 	return 0;
 }
 
@@ -838,32 +822,27 @@ static int check_rtp_origin(struct mgcp_conn_rtp *conn, struct osmo_sockaddr *ad
 {
 	char ipbuf[INET6_ADDRSTRLEN];
 
-	if (osmo_sockaddr_is_any(&conn->end.addr) != 0) {
-		switch (conn->conn->mode) {
-		case MGCP_CONN_LOOPBACK:
-			/* HACK: for IuUP, we want to reply with an IuUP Initialization ACK upon the first RTP
-			 * message received. We currently hackishly accomplish that by putting the endpoint in
-			 * loopback mode and patching over the looped back RTP message to make it look like an
-			 * ack. We don't know the femto cell's IP address and port until the RAB Assignment
-			 * Response is received, but the nano3G expects an IuUP Initialization Ack before it even
-			 * sends the RAB Assignment Response. Hence, if the remote address is 0.0.0.0 and the
-			 * MGCP port is in loopback mode, allow looping back the packet to any source. */
-			LOGPCONN(conn->conn, DRTP, LOGL_ERROR,
-				 "In loopback mode and remote address not set:"
-				 " allowing data from address: %s\n",
-				 osmo_sockaddr_ntop(&addr->u.sa, ipbuf));
-			return 0;
-
-		default:
-			/* Receiving early media before the endpoint is configured. Instead of logging
-			 * this as an error that occurs on every call, keep it more low profile to not
-			 * confuse humans with expected errors. */
+	if (osmo_sockaddr_is_any(&conn->end.addr) != 0 ||
+	    osmo_sockaddr_port(&conn->end.addr.u.sa) == 0) {
+		if (mgcp_conn_rtp_is_iuup(conn) && !conn->iuup.configured) {
+			/* Allow IuUP Initialization to get through even if we don't have a remote address set yet.
+			 * This is needed because hNodeB doesn't announce its IuUP remote IP addr to the MGCP client
+			 * (RAB Assignment Response at HNBGW) until it has gone through IuUP Initialization against
+			 * this MGW here. Hence the MGW may not yet know the remote IuUP address and port at the time
+			 * of receiving IuUP Initialization from the hNodeB.
+			 */
 			LOGPCONN(conn->conn, DRTP, LOGL_INFO,
-				 "Rx RTP from %s, but remote address not set:"
-				 " dropping early media\n",
-				 osmo_sockaddr_ntop(&addr->u.sa, ipbuf));
-			return -1;
+				 "Rx RTP from %s: allowing unknown src for IuUP Initialization\n",
+				 osmo_sockaddr_to_str(addr));
+			return 0;
 		}
+		/* Receiving early media before the endpoint is configured. Instead of logging
+		 * this as an error that occurs on every call, keep it more low profile to not
+		 * confuse humans with expected errors. */
+		LOGPCONN(conn->conn, DRTP, LOGL_INFO,
+			 "Rx RTP from %s, but remote address not set: dropping early media\n",
+			 osmo_sockaddr_to_str(addr));
+		return -1;
 	}
 
 	/* Note: Check if the inbound RTP data comes from the same host to
@@ -875,11 +854,8 @@ static int check_rtp_origin(struct mgcp_conn_rtp *conn, struct osmo_sockaddr *ad
 	     memcmp(&conn->end.addr.u.sin6.sin6_addr, &addr->u.sin6.sin6_addr,
 		    sizeof(struct in6_addr)))) {
 		LOGPCONN(conn->conn, DRTP, LOGL_ERROR,
-			 "data from wrong address: %s, ",
-			 osmo_sockaddr_ntop(&addr->u.sa, ipbuf));
-		LOGPC(DRTP, LOGL_ERROR, "expected: %s\n",
-		      osmo_sockaddr_ntop(&conn->end.addr.u.sa, ipbuf));
-		LOGPCONN(conn->conn, DRTP, LOGL_ERROR, "packet tossed\n");
+			 "data from wrong src %s, expected IP Address %s. Packet tossed.\n",
+			 osmo_sockaddr_to_str(addr), osmo_sockaddr_ntop(&conn->end.addr.u.sa, ipbuf));
 		return -1;
 	}
 
@@ -890,12 +866,9 @@ static int check_rtp_origin(struct mgcp_conn_rtp *conn, struct osmo_sockaddr *ad
 	if (osmo_sockaddr_port(&conn->end.addr.u.sa) != osmo_sockaddr_port(&addr->u.sa) &&
 	    ntohs(conn->end.rtcp_port) != osmo_sockaddr_port(&addr->u.sa)) {
 		LOGPCONN(conn->conn, DRTP, LOGL_ERROR,
-			 "data from wrong source port: %d, ",
-			 osmo_sockaddr_port(&addr->u.sa));
-		LOGPC(DRTP, LOGL_ERROR,
-		      "expected: %d for RTP or %d for RTCP\n",
-		      osmo_sockaddr_port(&conn->end.addr.u.sa), ntohs(conn->end.rtcp_port));
-		LOGPCONN(conn->conn, DRTP, LOGL_ERROR, "packet tossed\n");
+			 "data from wrong src %s, expected port: %u for RTP or %u for RTCP. Packet tossed.\n",
+			 osmo_sockaddr_to_str(addr), osmo_sockaddr_port(&conn->end.addr.u.sa),
+			 ntohs(conn->end.rtcp_port));
 		return -1;
 	}
 
@@ -1134,12 +1107,11 @@ failed:
 /*! Send RTP/RTCP data to a specified destination connection.
  *  \param[in] endp associated endpoint (for configuration, logging).
  *  \param[in] is_rtp flag to specify if the packet is of type RTP or RTCP.
- *  \param[in] spoofed source address (set to NULL to disable).
- *  \param[in] buf buffer that contains the RTP/RTCP data.
- *  \param[in] len length of the buffer that contains the RTP/RTCP data.
+ *  \param[in] addr spoofed source address (set to NULL to disable).
+ *  \param[in] msg message buffer that contains the RTP/RTCP data.
  *  \param[in] conn_src associated source connection.
  *  \param[in] conn_dst associated destination connection.
- *  \returns 0 on success, -1 on ERROR. */
+ *  \returns 0 on success, negative on ERROR. */
 int mgcp_send(struct mgcp_endpoint *endp, int is_rtp, struct osmo_sockaddr *addr,
 	      struct msgb *msg, struct mgcp_conn_rtp *conn_src,
 	      struct mgcp_conn_rtp *conn_dst)
@@ -1169,18 +1141,9 @@ int mgcp_send(struct mgcp_endpoint *endp, int is_rtp, struct osmo_sockaddr *addr
 	 * IuUP -> AMR: calls this function, skip patching if conn_src is IuUP.
 	 * {AMR or IuUP} -> IuUP: calls mgcp_udp_send() directly, skipping this function: No need to examine dst. */
 	if (is_rtp && !mgcp_conn_rtp_is_iuup(conn_src)) {
-		rc = mgcp_patch_pt(conn_src, conn_dst, msg);
-		if (rc < 0) {
-			/* FIXME: It is legal that the payload type on the egress connection is
-			 * different from the payload type that has been negotiated on the
-			 * ingress connection. Essentially the codecs are the same so we can
-			 * match them and patch the payload type. However, if we can not find
-			 * the codec pendant (everything ist equal except the PT), we are of
-			 * course unable to patch the payload type. A situation like this
-			 * should not occur if transcoding is consequently avoided. Until
-			 * we have transcoding support in osmo-mgw we can not resolve this. */
-			LOGPENDP(endp, DRTP, LOGL_DEBUG,
-				 "can not patch PT because no suitable egress codec was found.\n");
+		if (mgcp_patch_pt(conn_dst, msg) < 0) {
+			LOGPENDP(endp, DRTP, LOGL_NOTICE, "unable to patch payload type RTP packet, discarding...\n");
+			return -EINVAL;
 		}
 	}
 
@@ -1226,12 +1189,12 @@ int mgcp_send(struct mgcp_endpoint *endp, int is_rtp, struct osmo_sockaddr *addr
 			if (mgcp_conn_rtp_is_iuup(conn_dst) || mgcp_conn_rtp_is_iuup(conn_src)) {
 				/* the iuup code will correctly transform to the correct AMR mode */
 			} else if (mgcp_codec_amr_align_mode_is_indicated(conn_dst->end.codec)) {
-				rc = amr_oa_bwe_convert(endp, msg,
-							conn_dst->end.codec->param.amr_octet_aligned);
+				bool oa = mgcp_codec_amr_is_octet_aligned(conn_dst->end.codec);
+				rc = amr_oa_bwe_convert(endp, msg, oa);
 				if (rc < 0) {
 					LOGPENDP(endp, DRTP, LOGL_ERROR,
 						 "Error in AMR octet-aligned <-> bandwidth-efficient mode conversion (target=%s)\n",
-						 conn_dst->end.codec->param.amr_octet_aligned ? "octet-aligned" : "bandwidth-efficient");
+						 oa ? "octet-aligned" : "bandwidth-efficient");
 					break;
 				}
 			} else if (rtp_end->rfc5993_hr_convert &&
@@ -1304,8 +1267,10 @@ int mgcp_dispatch_rtp_bridge_cb(struct msgb *msg)
 	struct mgcp_conn_rtp *conn_src = mc->conn_src;
 	struct mgcp_conn *conn = conn_src->conn;
 	struct mgcp_conn *conn_dst;
+	struct mgcp_endpoint *endp = conn->endp;
 	struct osmo_sockaddr *from_addr = mc->from_addr;
 	char ipbuf[INET6_ADDRSTRLEN];
+	int rc = 0;
 
 	/*! NOTE: This callback function implements the endpoint specific
 	 *  dispatch behaviour of an rtp bridge/proxy endpoint. It is assumed
@@ -1337,36 +1302,35 @@ int mgcp_dispatch_rtp_bridge_cb(struct msgb *msg)
 		return mgcp_conn_rtp_dispatch_rtp(conn_src, msg);
 	}
 
-	/* Find a destination connection. */
-	/* NOTE: This code path runs every time an RTP packet is received. The
-	 * function mgcp_find_dst_conn() we use to determine the detination
-	 * connection will iterate the connection list inside the endpoint.
-	 * Since list iterations are quite costly, we will figure out the
-	 * destination only once and use the optional private data pointer of
-	 * the connection to cache the destination connection pointer. */
-	if (!conn->priv) {
-		conn_dst = mgcp_find_dst_conn(conn);
-		conn->priv = conn_dst;
-	} else {
-		conn_dst = (struct mgcp_conn *)conn->priv;
+	/* If the mode does not allow receiving RTP, we are done. */
+	switch (conn->mode) {
+	case MGCP_CONN_RECV_ONLY:
+	case MGCP_CONN_RECV_SEND:
+	case MGCP_CONN_CONFECHO:
+		break;
+	default:
+		return rc;
 	}
 
-	/* There is no destination conn, stop here */
-	if (!conn_dst) {
-		LOGPCONN(conn, DRTP, LOGL_DEBUG,
-			 "no connection to forward an incoming RTP packet to\n");
-		return -1;
-	}
+	/* If the mode is "confecho", send RTP back to the sender. */
+	if (conn->mode == MGCP_CONN_CONFECHO)
+		rc = mgcp_conn_rtp_dispatch_rtp(conn_src, msg);
 
-	/* The destination conn is not an RTP connection */
-	if (conn_dst->type != MGCP_CONN_TYPE_RTP) {
-		LOGPCONN(conn, DRTP, LOGL_ERROR,
-			 "unable to find suitable destination conn\n");
-		return -1;
+	/* Dispatch RTP packet to all other connection(s) that send audio. */
+	llist_for_each_entry(conn_dst, &endp->conns, entry) {
+		if (conn_dst == conn)
+			continue;
+		switch (conn_dst->mode) {
+		case MGCP_CONN_SEND_ONLY:
+		case MGCP_CONN_RECV_SEND:
+		case MGCP_CONN_CONFECHO:
+			rc = mgcp_conn_rtp_dispatch_rtp(&conn_dst->u.rtp, msg);
+			break;
+		default:
+			break;
+		}
 	}
-
-	/* Dispatch RTP packet to destination RTP connection */
-	return mgcp_conn_rtp_dispatch_rtp(&conn_dst->u.rtp, msg);
+	return rc;
 }
 
 /*! dispatch incoming RTP packet to E1 subslot, handle RTCP packets locally.
@@ -1537,20 +1501,22 @@ static int rx_rtp(struct msgb *msg)
 	if (!trunk->rtp_accept_all && check_rtp_origin(conn_src, from_addr))
 		return -1;
 
-	/* If AMR is configured for the ingress connection and conversion of the
-	 * framing mode (octet-aligned vs. bandwith-efficient) is explicitly
-	 * defined, then we check if the incoming payload matches that
-	 * expectation. */
-	if (mc->proto == MGCP_PROTO_RTP &&
-	    mgcp_codec_amr_align_mode_is_indicated(conn_src->end.codec)) {
+	/* Handle AMR frame format conversion (octet-aligned vs. bandwith-efficient) */
+	if (mc->proto == MGCP_PROTO_RTP
+	    && conn_src->end.codec
+	    && mgcp_codec_amr_align_mode_is_indicated(conn_src->end.codec)) {
+		bool src_oa;
+		/* Make sure that the incoming AMR frame format matches the frame format that the call agent has
+		 * communicated via SDP when the connection was created/modfied. */
 		int oa = amr_oa_check((char*)msgb_data(msg), msgb_length(msg));
 		if (oa < 0)
 			return -1;
-		if (((bool)oa) != conn_src->end.codec->param.amr_octet_aligned) {
+		src_oa = mgcp_codec_amr_is_octet_aligned(conn_src->end.codec);
+		if (((bool)oa) != src_oa) {
 			LOG_CONN_RTP(conn_src, LOGL_NOTICE,
 				     "rx_rtp(%u bytes): Expected RTP AMR octet-aligned=%u but got octet-aligned=%u."
 				     " check the config of your call-agent!\n",
-				     msgb_length(msg), conn_src->end.codec->param.amr_octet_aligned, oa);
+				     msgb_length(msg), src_oa, oa);
 			return -1;
 		}
 	}
@@ -1677,14 +1643,14 @@ int mgcp_bind_net_rtp_port(struct mgcp_endpoint *endp, int rtp_port,
 void mgcp_free_rtp_port(struct mgcp_rtp_end *end)
 {
 	if (end->rtp.fd != -1) {
+		osmo_fd_unregister(&end->rtp);
 		close(end->rtp.fd);
 		end->rtp.fd = -1;
-		osmo_fd_unregister(&end->rtp);
 	}
 
 	if (end->rtcp.fd != -1) {
+		osmo_fd_unregister(&end->rtcp);
 		close(end->rtcp.fd);
 		end->rtcp.fd = -1;
-		osmo_fd_unregister(&end->rtcp);
 	}
 }

src/libosmo-mgcp/mgcp_osmux.c

@@ -155,6 +155,7 @@ osmux_handle_alloc(const struct mgcp_trunk *trunk, const struct osmo_sockaddr *r
 {
 	struct osmux_handle *h;
 	const struct mgcp_config *cfg = trunk->cfg;
+	char name[128] = "r=";
 
 	h = talloc_zero(trunk, struct osmux_handle);
 	if (!h)
@@ -167,6 +168,9 @@ osmux_handle_alloc(const struct mgcp_trunk *trunk, const struct osmo_sockaddr *r
 		talloc_free(h);
 		return NULL;
 	}
+
+	osmo_sockaddr_to_str_buf(name + 2, sizeof(name) - 2, rem_addr);
+	osmux_xfrm_input_set_name(h->in, name);
 	/* sequence number to start OSMUX message from */
 	osmux_xfrm_input_set_initial_seqnum(h->in, 0);
 	osmux_xfrm_input_set_batch_factor(h->in, cfg->osmux.batch_factor);
@@ -734,26 +738,46 @@ int osmux_cid_pool_count_used(void)
 	return used;
 }
 
-/*! take a free OSMUX cid.
+/*! Find and reserve a free OSMUX cid. Keep state of last allocated CID to
+ *  rotate allocated CIDs over time. This helps in letting CIDs unused for some
+ *  time after last use.
  *  \returns OSMUX cid */
 int osmux_cid_pool_get_next(void)
 {
-	int i, j;
+	static uint8_t next_free_osmux_cid_lookup = 0;
+	uint8_t start_i, start_j;
+	uint8_t i, j, cid;
 
-	for (i = 0; i < sizeof(osmux_cid_bitmap); i++) {
-		for (j = 0; j < 8; j++) {
+	/* i = octet index, j = bit index inside ith octet */
+	start_i = next_free_osmux_cid_lookup >> 3;
+	start_j = next_free_osmux_cid_lookup & 0x07;
+
+	for (i = start_i; i < sizeof(osmux_cid_bitmap); i++) {
+		for (j = start_j; j < 8; j++) {
 			if (osmux_cid_bitmap[i] & (1 << j))
 				continue;
+			goto found;
+		}
+	}
 
-			osmux_cid_bitmap[i] |= (1 << j);
-			LOGP(DOSMUX, LOGL_DEBUG,
-			     "Allocating Osmux CID %u from pool\n", (i * 8) + j);
-			return (i * 8) + j;
+	for (i = 0; i <= start_i; i++) {
+		for (j = 0; j < start_j; j++) {
+			if (osmux_cid_bitmap[i] & (1 << j))
+				continue;
+			goto found;
 		}
 	}
 
 	LOGP(DOSMUX, LOGL_ERROR, "All Osmux circuits are in use!\n");
 	return -1;
+
+found:
+	osmux_cid_bitmap[i] |= (1 << j);
+	cid = (i << 3) | j;
+	next_free_osmux_cid_lookup = (cid + 1) & 0xff;
+	LOGP(DOSMUX, LOGL_DEBUG,
+		"Allocating Osmux CID %u from pool\n", cid);
+	return cid;
 }
 
 /*! take a specific OSMUX cid.

src/libosmo-mgcp/mgcp_protocol.c

@@ -86,6 +86,9 @@ struct mgcp_request_data {
 	/* set to true when the request has been classified as wildcarded */
 	bool wildcarded;
 
+	/* Set to true when the request is targeted at the "null" endpoint */
+	bool null_endp;
+
 	/* contains cause code in case of problems during endp/trunk resolution */
 	int mgcp_cause;
 };
@@ -390,7 +393,10 @@ struct msgb *mgcp_handle_message(struct mgcp_config *cfg, struct msgb *msg)
 	/* Locate endpoint and trunk, if no endpoint can be located try at least to identify the trunk. */
 	rq.pdata = &pdata;
 	rq.wildcarded = mgcp_endp_is_wildcarded(pdata.epname);
-	rq.endp = mgcp_endp_by_name(&rc, pdata.epname, pdata.cfg);
+	if (!rq.wildcarded)
+		rq.null_endp = mgcp_endp_is_null(pdata.epname);
+	if (!rq.null_endp)
+		rq.endp = mgcp_endp_by_name(&rc, pdata.epname, pdata.cfg);
 	rq.mgcp_cause = rc;
 	if (!rq.endp) {
 		rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_GENERAL_RX_FAIL_NO_ENDPOINT));
@@ -407,14 +413,14 @@ struct msgb *mgcp_handle_message(struct mgcp_config *cfg, struct msgb *msg)
 				     rq.name, pdata.epname);
 				return create_err_response(cfg, NULL, -rq.mgcp_cause, rq.name, pdata.trans);
 			}
-		} else {
+		} else if (!rq.null_endp) {
 			/* If the endpoint name suggests that the request refers to a specific endpoint, then the
 			 * request cannot be handled and we must stop early. */
 			LOGP(DLMGCP, LOGL_NOTICE,
 			     "%s: cannot find endpoint \"%s\", cause=%d -- abort\n", rq.name,
 			     pdata.epname, -rq.mgcp_cause);
 			return create_err_response(cfg, NULL, -rq.mgcp_cause, rq.name, pdata.trans);
-		}
+		} /* else: Handle special "null" endpoint below (with rq.endp=NULL, rq.trunk=NULL) */
 	} else {
 		osmo_strlcpy(debug_last_endpoint_name, rq.endp->name, sizeof(debug_last_endpoint_name));
 		rq.trunk = rq.endp->trunk;
@@ -460,6 +466,11 @@ struct msgb *mgcp_handle_message(struct mgcp_config *cfg, struct msgb *msg)
 static struct msgb *handle_audit_endpoint(struct mgcp_request_data *rq)
 {
 	LOGPENDP(rq->endp, DLMGCP, LOGL_NOTICE, "AUEP: auditing endpoint ...\n");
+
+	/* Auditing "null" endpoint is allowed for keepalive purposes. There's no rq->endp nor rq->trunk in this case. */
+	if (rq->null_endp)
+		return create_ok_response(rq->pdata->cfg, NULL, 200, "AUEP", rq->pdata->trans);
+
 	if (!rq->endp || !mgcp_endp_avail(rq->endp)) {
 		LOGPENDP(rq->endp, DLMGCP, LOGL_ERROR, "AUEP: selected endpoint not available!\n");
 		return create_err_response(rq->trunk, NULL, 501, "AUEP", rq->pdata->trans);
@@ -661,8 +672,8 @@ static int set_local_cx_options(void *ctx, struct mgcp_lco *lco,
 		case 'a':
 			/* FIXME: LCO also supports the negotiation of more than one codec.
 			 * (e.g. a:PCMU;G726-32) But this implementation only supports a single
-			 * codec only. */
-			if (sscanf(lco_id + 1, ":%16[^,]", codec) == 1) {
+			 * codec only. Ignoring all but the first codec. */
+			if (sscanf(lco_id + 1, ":%16[^,;]", codec) == 1) {
 				talloc_free(lco->codec);
 				/* MGCP header is case insensive, and we'll need
 				   codec in uppercase when using it later: */
@@ -761,6 +772,9 @@ static int handle_codec_info(struct mgcp_conn_rtp *conn,
 			     struct mgcp_request_data *rq, int have_sdp, bool crcx)
 {
 	struct mgcp_endpoint *endp = rq->endp;
+	struct mgcp_conn *conn_dst;
+	struct mgcp_conn_rtp *conn_dst_rtp;
+
 	int rc;
 	char *cmd;
 
@@ -802,8 +816,15 @@ static int handle_codec_info(struct mgcp_conn_rtp *conn,
 			goto error;
 	}
 
+	/* Try to find an destination RTP connection that we can include in the codec decision. */
+	conn_dst = mgcp_find_dst_conn(conn->conn);
+	if (conn_dst && conn_dst->type == MGCP_CONN_TYPE_RTP)
+		conn_dst_rtp = &conn_dst->u.rtp;
+	else
+		conn_dst_rtp = NULL;
+
 	/* Make codec decision */
-	if (mgcp_codec_decide(conn) != 0)
+	if (mgcp_codec_decide(conn, conn_dst_rtp) != 0)
 		goto error;
 
 	return 0;
@@ -845,7 +866,7 @@ static struct msgb *handle_create_con(struct mgcp_request_data *rq)
 	struct mgcp_parse_data *pdata = rq->pdata;
 	struct mgcp_trunk *trunk = rq->trunk;
 	struct mgcp_endpoint *endp = rq->endp;
-	struct rate_ctr_group *rate_ctrs = trunk->ratectr.mgcp_crcx_ctr_group;
+	struct rate_ctr_group *rate_ctrs;
 	int error_code = 400;
 	const char *local_options = NULL;
 	const char *callid = NULL;
@@ -859,6 +880,14 @@ static struct msgb *handle_create_con(struct mgcp_request_data *rq)
 
 	LOGPENDP(endp, DLMGCP, LOGL_NOTICE, "CRCX: creating new connection ...\n");
 
+	if (rq->null_endp) {
+		/* trunk not available so rate_ctr aren't available either. */
+		LOGP(DLMGCP, LOGL_ERROR, "CRCX: Not allowed in 'null' endpoint!\n");
+		return create_err_response(pdata->cfg, NULL, 502, "CRCX", pdata->trans);
+	}
+
+	rate_ctrs = trunk->ratectr.mgcp_crcx_ctr_group;
+
 	/* we must have a free ep */
 	if (!endp) {
 		rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_CRCX_FAIL_AVAIL));
@@ -938,7 +967,7 @@ mgcp_header_done:
 	}
 
 	/* Check if we are able to accept the creation of another connection */
-	if (llist_count(&endp->conns) >= endp->type->max_conns) {
+	if (endp->type->max_conns > 0 && llist_count(&endp->conns) >= endp->type->max_conns) {
 		LOGPENDP(endp, DLMGCP, LOGL_ERROR,
 			"CRCX: endpoint full, max. %i connections allowed!\n",
 			endp->type->max_conns);
@@ -1026,7 +1055,7 @@ mgcp_header_done:
 					  &endp->local_options, local_options);
 		if (rc != 0) {
 			LOGPCONN(_conn, DLMGCP, LOGL_ERROR,
-				 "CRCX: inavlid local connection options!\n");
+				 "CRCX: invalid local connection options!\n");
 			error_code = rc;
 			rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_CRCX_FAIL_INVALID_CONN_OPTIONS));
 			goto error2;
@@ -1047,9 +1076,6 @@ mgcp_header_done:
 		rc = mgcp_conn_iuup_init(conn);
 	}
 
-	conn->end.fmtp_extra = talloc_strdup(trunk->endpoints,
-					     trunk->audio_fmtp_extra);
-
 	if (pdata->cfg->force_ptime) {
 		conn->end.packet_duration_ms = pdata->cfg->force_ptime;
 		conn->end.force_output_ptime = 1;
@@ -1105,6 +1131,7 @@ mgcp_header_done:
 
 	LOGPCONN(_conn, DLMGCP, LOGL_NOTICE,
 		 "CRCX: connection successfully created\n");
+
 	rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_CRCX_SUCCESS));
 	mgcp_endp_update(endp);
 
@@ -1124,7 +1151,7 @@ static struct msgb *handle_modify_con(struct mgcp_request_data *rq)
 	struct mgcp_parse_data *pdata = rq->pdata;
 	struct mgcp_trunk *trunk = rq->trunk;
 	struct mgcp_endpoint *endp = rq->endp;
-	struct rate_ctr_group *rate_ctrs = trunk->ratectr.mgcp_mdcx_ctr_group;
+	struct rate_ctr_group *rate_ctrs;
 	char new_local_addr[INET6_ADDRSTRLEN];
 	int error_code = 500;
 	int silent = 0;
@@ -1139,6 +1166,14 @@ static struct msgb *handle_modify_con(struct mgcp_request_data *rq)
 
 	LOGPENDP(endp, DLMGCP, LOGL_NOTICE, "MDCX: modifying existing connection ...\n");
 
+	if (rq->null_endp) {
+		/* trunk not available so rate_ctr aren't available either. */
+		LOGP(DLMGCP, LOGL_ERROR, "MDCX: Not allowed in 'null' endpoint!\n");
+		return create_err_response(pdata->cfg, NULL, 502, "MDCX", pdata->trans);
+	}
+
+	rate_ctrs = trunk->ratectr.mgcp_mdcx_ctr_group;
+
 	/* Prohibit wildcarded requests */
 	if (rq->wildcarded) {
 		LOGPENDP(endp, DLMGCP, LOGL_ERROR,
@@ -1256,6 +1291,10 @@ mgcp_header_done:
 		error_code = rc;
 		goto error3;
 	}
+	/* Upgrade the conn type RTP_DEFAULT->RTP_IUUP if needed based on requested codec: */
+	/* TODO: "codec" probably needs to be moved from endp to conn */
+	if (conn->type == MGCP_RTP_DEFAULT && strcmp(conn->end.codec->subtype_name, "VND.3GPP.IUFP") == 0)
+		rc = mgcp_conn_iuup_init(conn);
 
 	/* check connection mode setting */
 	if (conn->conn->mode != MGCP_CONN_LOOPBACK
@@ -1350,7 +1389,7 @@ static struct msgb *handle_delete_con(struct mgcp_request_data *rq)
 	struct mgcp_parse_data *pdata = rq->pdata;
 	struct mgcp_trunk *trunk = rq->trunk;
 	struct mgcp_endpoint *endp = rq->endp;
-	struct rate_ctr_group *rate_ctrs = trunk->ratectr.mgcp_dlcx_ctr_group;
+	struct rate_ctr_group *rate_ctrs;
 	int error_code = 400;
 	int silent = 0;
 	char *line;
@@ -1360,10 +1399,18 @@ static struct msgb *handle_delete_con(struct mgcp_request_data *rq)
 	unsigned int i;
 
 	/* NOTE: In this handler we can not take it for granted that the endp
-	 * pointer will be populated, however a trunk is always guaranteed. */
+	 * pointer will be populated, however a trunk is always guaranteed (except for 'null' endp).
+	 */
 
 	LOGPEPTR(endp, trunk, DLMGCP, LOGL_NOTICE, "DLCX: deleting connection(s) ...\n");
 
+	if (rq->null_endp) {
+		/* trunk not available so rate_ctr aren't available either. */
+		LOGP(DLMGCP, LOGL_ERROR, "DLCX: Not allowed in 'null' endpoint!\n");
+		return create_err_response(pdata->cfg, NULL, 502, "DLCX", pdata->trans);
+	}
+
+	rate_ctrs = trunk->ratectr.mgcp_dlcx_ctr_group;
 	if (endp && !mgcp_endp_avail(endp)) {
 		rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_DLCX_FAIL_AVAIL));
 		LOGPENDP(endp, DLMGCP, LOGL_ERROR,
@@ -1514,6 +1561,12 @@ static struct msgb *handle_rsip(struct mgcp_request_data *rq)
 
 	LOGP(DLMGCP, LOGL_NOTICE, "RSIP: resetting all endpoints ...\n");
 
+	if (rq->null_endp) {
+		/* trunk not available so rate_ctr aren't available either. */
+		LOGP(DLMGCP, LOGL_ERROR, "RSIP: Not allowed in 'null' endpoint!\n");
+		return create_err_response(rq->pdata->cfg, NULL, 502, "RSIP", rq->pdata->trans);
+	}
+
 	if (rq->pdata->cfg->reset_cb)
 		rq->pdata->cfg->reset_cb(rq->endp->trunk);
 	return NULL;
@@ -1539,6 +1592,12 @@ static struct msgb *handle_noti_req(struct mgcp_request_data *rq)
 
 	LOGP(DLMGCP, LOGL_NOTICE, "RQNT: processing request for notification ...\n");
 
+	if (rq->null_endp) {
+		/* trunk not available so rate_ctr aren't available either. */
+		LOGP(DLMGCP, LOGL_ERROR, "RQNT: Not allowed in 'null' endpoint!\n");
+		return create_err_response(rq->pdata->cfg, NULL, 502, "RQNT", rq->pdata->trans);
+	}
+
 	for_each_line(line, rq->pdata->save) {
 		switch (toupper(line[0])) {
 		case 'S':
@@ -1651,8 +1710,6 @@ struct mgcp_config *mgcp_config_alloc(void)
 	cfg->rtp_processing_cb = &mgcp_rtp_processing_default;
 	cfg->setup_rtp_processing_cb = &mgcp_setup_rtp_processing_default;
 
-	cfg->get_net_downlink_format_cb = &mgcp_get_net_downlink_format_default;
-
 	INIT_LLIST_HEAD(&cfg->trunks);
 
 	/* Allocate virtual trunk */

src/libosmo-mgcp/mgcp_sdp.c

@@ -35,6 +35,9 @@
 #include <osmocom/mgcp/mgcp_sdp.h>
 #include <osmocom/mgcp/mgcp_protocol.h>
 
+#include <osmocom/sdp/fmtp.h>
+#include <osmocom/sdp/sdp_strings.h>
+
 #include <errno.h>
 #include <stdlib.h>
 #include <limits.h>
@@ -55,7 +58,7 @@ struct sdp_rtp_map {
 };
 struct sdp_fmtp_param {
 	int payload_type;
-	struct mgcp_codec_param param;
+	const char *fmtp;
 };
 
 
@@ -195,11 +198,7 @@ static int fmtp_from_sdp(void *ctx, struct sdp_fmtp_param *fmtp_param, char *sdp
 {
 	char *str;
 	char *str_ptr;
-	char *param_str;
 	unsigned int pt;
-	unsigned int count = 0;
-	char delimiter;
-	unsigned int amr_octet_aligned;
 
 	memset(fmtp_param, 0, sizeof(*fmtp_param));
 
@@ -218,41 +217,13 @@ static int fmtp_from_sdp(void *ctx, struct sdp_fmtp_param *fmtp_param, char *sdp
 		goto error;
 	fmtp_param->payload_type = pt;
 
-	/* Advance pointer to the beginning of the parameter section and
-	 * tokenize string */
+	/* Advance pointer to the beginning of the parameter section */
 	str_ptr = strstr(str_ptr, " ");
 	if (!str_ptr)
 		goto error;
 	str_ptr++;
 
-	param_str = strtok(str_ptr, " ");
-	if (!param_str)
-		goto exit;
-
-	while (1) {
-		/* Make sure that we don't get trapped in an endless loop */
-		if (count > 256)
-			goto error;
-
-		/* Chop off delimiters ';' at the end */
-		delimiter = str_ptr[strlen(str_ptr) - 1];
-		if (delimiter == ';' || delimiter == ',')
-			str_ptr[strlen(str_ptr) - 1] = '\0';
-
-		/* AMR octet aligned parameter */
-		if (sscanf(param_str, "octet-align=%d", &amr_octet_aligned) == 1) {
-			fmtp_param->param.amr_octet_aligned_present = true;
-			fmtp_param->param.amr_octet_aligned = false;
-			if (amr_octet_aligned == 1)
-				fmtp_param->param.amr_octet_aligned = true;
-
-		}
-
-		param_str = strtok(NULL, " ");
-		if (!param_str)
-			break;
-		count++;
-	}
+	fmtp_param->fmtp = talloc_strdup(ctx, str_ptr);
 
 exit:
 	talloc_free(str);
@@ -300,13 +271,13 @@ static int audio_ip_from_sdp(struct osmo_sockaddr *dst_addr, char *sdp)
 
 /* Pick optional fmtp parameters by payload type, if there are no fmtp
  * parameters, a nullpointer is returned */
-static struct mgcp_codec_param *param_by_pt(int pt, struct sdp_fmtp_param *fmtp_params, unsigned int fmtp_params_len)
+static const char *param_by_pt(int pt, struct sdp_fmtp_param *fmtp_params, unsigned int fmtp_params_len)
 {
 	unsigned int i;
 
 	for (i = 0; i < fmtp_params_len; i++) {
 		if (fmtp_params[i].payload_type == pt)
-			return &fmtp_params[i].param;
+			return fmtp_params[i].fmtp;
 	}
 
 	return NULL;
@@ -327,7 +298,6 @@ int mgcp_parse_sdp_data(const struct mgcp_endpoint *endp,
 	unsigned int codecs_used = 0;
 	struct sdp_fmtp_param fmtp_params[MGCP_MAX_CODECS];
 	unsigned int fmtp_used = 0;
-	struct mgcp_codec_param *codec_param;
 	char ipbuf[INET6_ADDRSTRLEN];
 	char *line;
 	unsigned int i;
@@ -422,8 +392,8 @@ int mgcp_parse_sdp_data(const struct mgcp_endpoint *endp,
 
 	/* Store parsed codec information */
 	for (i = 0; i < codecs_used; i++) {
-		codec_param = param_by_pt(codecs[i].payload_type, fmtp_params, fmtp_used);
-		rc = mgcp_codec_add(conn, codecs[i].payload_type, codecs[i].map_line, codec_param);
+		const char *fmtp = param_by_pt(codecs[i].payload_type, fmtp_params, fmtp_used);
+		rc = mgcp_codec_add2(conn, codecs[i].payload_type, codecs[i].map_line, fmtp);
 		if (rc < 0)
 			LOGPENDP(endp, DLMGCP, LOGL_NOTICE, "failed to add codec\n");
 	}
@@ -437,10 +407,12 @@ int mgcp_parse_sdp_data(const struct mgcp_endpoint *endp,
 	if (codecs_used == 0)
 		LOGPC(DLMGCP, LOGL_NOTICE, "none");
 	for (i = 0; i < codecs_used; i++) {
-		LOGPC(DLMGCP, LOGL_NOTICE, "%d=%s",
+		LOGPC(DLMGCP, LOGL_NOTICE, " %d=%s%s%s%s",
 		      rtp->codecs[i].payload_type,
-		      strlen(rtp->codecs[i].subtype_name) ? rtp->codecs[i].subtype_name : "unknown");
-		LOGPC(DLMGCP, LOGL_NOTICE, " ");
+		      strlen(rtp->codecs[i].subtype_name) ? rtp->codecs[i].subtype_name : "unknown",
+		      rtp->codecs[i].fmtp[0] ? ",fmtp='" : "",
+		      rtp->codecs[i].fmtp,
+		      rtp->codecs[i].fmtp[0] ? "'" : "");
 	}
 	LOGPC(DLMGCP, LOGL_NOTICE, "\n");
 
@@ -489,55 +461,21 @@ static int add_audio(struct msgb *sdp, int *payload_types, unsigned int payload_
 }
 
 /* Add fmtp strings to sdp payload */
-static int add_fmtp(struct msgb *sdp, struct sdp_fmtp_param *fmtp_params, unsigned int fmtp_params_len,
-		    const char *fmtp_extra)
+static int add_fmtp(struct msgb *sdp, struct sdp_fmtp_param *fmtp_params, unsigned int fmtp_params_len)
 {
 	unsigned int i;
 	int rc;
-	int fmtp_extra_pt = -1;
-	char *fmtp_extra_pars = "";
-
-	/* When no fmtp parameters ara available but an fmtp extra string
-	 * is configured, just add the fmtp extra string */
-	if (fmtp_params_len == 0 && fmtp_extra) {
-		return msgb_printf(sdp, "%s\r\n", fmtp_extra);
-	}
-
-	/* When there is fmtp extra configured we dissect it in order to drop
-	 * in the configured extra parameters at the right place when
-	 * generating the fmtp strings. */
-	if (fmtp_extra) {
-		if (sscanf(fmtp_extra, "a=fmtp:%d ", &fmtp_extra_pt) != 1)
-			fmtp_extra_pt = -1;
-
-		fmtp_extra_pars = strstr(fmtp_extra, " ");
-
-		if (!fmtp_extra_pars)
-			fmtp_extra_pars = "";
-		else
-			fmtp_extra_pars++;
-	}
 
 	for (i = 0; i < fmtp_params_len; i++) {
+		bool first = true;
 		rc = msgb_printf(sdp, "a=fmtp:%u", fmtp_params[i].payload_type);
 		if (rc < 0)
 			return -EINVAL;
 
 		/* Add amr octet align parameter */
-		if (fmtp_params[i].param.amr_octet_aligned_present) {
-			if (fmtp_params[i].param.amr_octet_aligned)
-				rc = msgb_printf(sdp, " octet-align=1");
-			else
-				rc = msgb_printf(sdp, " octet-align=0");
-			if (rc < 0)
-				return -EINVAL;
-		}
-
-		/* Append extra parameters from fmtp extra */
-		if (fmtp_params[i].payload_type == fmtp_extra_pt) {
-			rc = msgb_printf(sdp, " %s", fmtp_extra_pars);
-			if (rc < 0)
-				return -EINVAL;
+		if (fmtp_params[i].fmtp) {
+			msgb_printf(sdp, "%s%s", first ? " " : ";", fmtp_params[i].fmtp);
+			first = false;
 		}
 
 		rc = msgb_printf(sdp, "\r\n");
@@ -559,10 +497,8 @@ int mgcp_write_response_sdp(const struct mgcp_endpoint *endp,
 			    const char *addr)
 {
 	const struct mgcp_rtp_codec *codec;
-	const char *fmtp_extra;
 	const char *audio_name;
 	int payload_type;
-	struct sdp_fmtp_param fmtp_param;
 	int rc;
 	int payload_types[1];
 	int local_port;
@@ -575,10 +511,7 @@ int mgcp_write_response_sdp(const struct mgcp_endpoint *endp,
 	OSMO_ASSERT(sdp);
 	OSMO_ASSERT(addr);
 
-	/* FIXME: constify endp and conn args in get_net_donwlink_format_cb() */
-	endp->trunk->cfg->get_net_downlink_format_cb((struct mgcp_endpoint *)endp,
-					      &codec, &fmtp_extra,
-					      (struct mgcp_conn_rtp *)conn);
+	codec = conn->end.codec;
 
 	audio_name = codec->audio_name;
 	payload_type = codec->payload_type;
@@ -614,13 +547,23 @@ int mgcp_write_response_sdp(const struct mgcp_endpoint *endp,
 				goto buffer_too_small;
 		}
 
-		if (codec->param_present) {
-			fmtp_param.payload_type = payload_type;
-			fmtp_param.param = codec->param;
-			fmtp_params[0] = fmtp_param;
+		if (codec->fmtp[0]) {
+			fmtp_params[0] = (struct sdp_fmtp_param){
+				.payload_type = payload_type,
+				.fmtp = codec->fmtp,
+			};
 			fmtp_params_len = 1;
+		} else if (codec->param_present) {
+			/* Legacy */
+			fmtp_params[0] = (struct sdp_fmtp_param){
+				.payload_type = payload_type,
+			};
+			fmtp_params_len = 1;
+			fmtp_params[0].fmtp = (codec->param.amr_octet_aligned ?
+					       OSMO_SDP_STR_AMR_OCTET_ALIGN_1 : OSMO_SDP_STR_AMR_OCTET_ALIGN_0);
 		}
-		rc = add_fmtp(sdp, fmtp_params, fmtp_params_len, fmtp_extra);
+
+		rc = add_fmtp(sdp, fmtp_params, fmtp_params_len);
 		if (rc < 0)
 			goto buffer_too_small;
 	}

src/libosmo-mgcp/mgcp_vty.c

@@ -111,17 +111,12 @@ static int config_write_mgcp(struct vty *vty)
 			VTY_NEWLINE);
 	} else
 		vty_out(vty, " no rtp-patch%s", VTY_NEWLINE);
-	if (trunk->audio_fmtp_extra)
-		vty_out(vty, " sdp audio fmtp-extra %s%s",
-			trunk->audio_fmtp_extra, VTY_NEWLINE);
 	vty_out(vty, " %ssdp audio-payload send-ptime%s",
 		trunk->audio_send_ptime ? "" : "no ", VTY_NEWLINE);
 	vty_out(vty, " %ssdp audio-payload send-name%s",
 		trunk->audio_send_name ? "" : "no ", VTY_NEWLINE);
 	vty_out(vty, " number endpoints %u%s",
 		trunk->v.vty_number_endpoints, VTY_NEWLINE);
-	vty_out(vty, " %sallow-transcoding%s",
-		trunk->no_audio_transcoding ? "no " : "", VTY_NEWLINE);
 	if (strlen(g_cfg->call_agent_addr))
 		vty_out(vty, " call-agent ip %s%s", g_cfg->call_agent_addr,
 			VTY_NEWLINE);
@@ -189,7 +184,7 @@ static void dump_rtp_end(struct vty *vty, struct mgcp_conn_rtp *conn)
 		"   Payload Type: %d Rate: %u Channels: %d %s"
 		"   Frame Duration: %u Frame Denominator: %u%s"
 		"   FPP: %d Packet Duration: %u%s"
-		"   FMTP-Extra: %s Audio-Name: %s Sub-Type: %s%s"
+		"   Audio-Name: %s Sub-Type: %s%s"
 		"   Output-Enabled: %d Force-PTIME: %d%s",
 		tx_packets->current, tx_bytes->current, VTY_NEWLINE,
 		rx_packets->current, rx_bytes->current, VTY_NEWLINE,
@@ -200,7 +195,7 @@ static void dump_rtp_end(struct vty *vty, struct mgcp_conn_rtp *conn)
 		codec->payload_type, codec->rate, codec->channels, VTY_NEWLINE,
 		codec->frame_duration_num, codec->frame_duration_den,
 		VTY_NEWLINE, end->frames_per_packet, end->packet_duration_ms,
-		VTY_NEWLINE, end->fmtp_extra, codec->audio_name,
+		VTY_NEWLINE, codec->audio_name,
 		codec->subtype_name, VTY_NEWLINE, end->output_enabled,
 		end->force_output_ptime, VTY_NEWLINE);
 	if (mgcp_conn_rtp_is_osmux(conn)) {
@@ -513,6 +508,7 @@ DEFUN_DEPRECATED(cfg_mgcp_bind_early,
 		 BIND_STR
 		 "Bind local ports on start up\n" "Bind on demand\n" "Bind on startup\n")
 {
+	vty_out(vty, "%% Deprecated 'bind early (0|1)' config no longer has any effect%s", VTY_NEWLINE);
 	return CMD_SUCCESS;
 }
 
@@ -682,53 +678,40 @@ DEFUN_USRATTR(cfg_mgcp_no_rtp_force_ptime,
 	return CMD_SUCCESS;
 }
 
-DEFUN_USRATTR(cfg_mgcp_sdp_fmtp_extra,
-	      cfg_mgcp_sdp_fmtp_extra_cmd,
-	      X(MGW_CMD_ATTR_NEWCONN),
-	      "sdp audio fmtp-extra .NAME",
-	      "Add extra fmtp for the SDP file\n" "Audio\n" "Fmtp-extra\n"
-	      "Extra Information\n")
-{
-	struct mgcp_trunk *trunk = mgcp_trunk_by_num(g_cfg, MGCP_TRUNK_VIRTUAL, MGCP_VIRT_TRUNK_ID);
-	OSMO_ASSERT(trunk);
-	char *txt = argv_concat(argv, argc, 0);
-	if (!txt)
-		return CMD_WARNING;
-
-	osmo_talloc_replace_string(g_cfg, &trunk->audio_fmtp_extra, txt);
-	talloc_free(txt);
-	return CMD_SUCCESS;
-}
-
-DEFUN_USRATTR(cfg_mgcp_allow_transcoding,
-	      cfg_mgcp_allow_transcoding_cmd,
-	      X(MGW_CMD_ATTR_NEWCONN),
-	      "allow-transcoding", "Allow transcoding\n")
-{
-	struct mgcp_trunk *trunk = mgcp_trunk_by_num(g_cfg, MGCP_TRUNK_VIRTUAL, MGCP_VIRT_TRUNK_ID);
-	OSMO_ASSERT(trunk);
-	trunk->no_audio_transcoding = 0;
-	return CMD_SUCCESS;
-}
-
-DEFUN_USRATTR(cfg_mgcp_no_allow_transcoding,
-	      cfg_mgcp_no_allow_transcoding_cmd,
-	      X(MGW_CMD_ATTR_NEWCONN),
-	      "no allow-transcoding", NO_STR "Allow transcoding\n")
-{
-	struct mgcp_trunk *trunk = mgcp_trunk_by_num(g_cfg, MGCP_TRUNK_VIRTUAL, MGCP_VIRT_TRUNK_ID);
-	OSMO_ASSERT(trunk);
-	trunk->no_audio_transcoding = 1;
-	return CMD_SUCCESS;
-}
-
 #define SDP_STR "SDP File related options\n"
 #define AUDIO_STR "Audio payload options\n"
+
+DEFUN_DEPRECATED(cfg_mgcp_sdp_fmtp_extra,
+	      cfg_mgcp_sdp_fmtp_extra_cmd,
+	      "sdp audio fmtp-extra .NAME",
+	      SDP_STR AUDIO_STR "Deprecated, without effect since osmo-mgw v1.13\n" "Deprecated, without effect\n")
+{
+	vty_out(vty, "%% deprecated: the config option 'sdp audio fmtp-extra' has been removed.%s", VTY_NEWLINE);
+	return CMD_SUCCESS;
+}
+
+DEFUN_DEPRECATED(cfg_mgcp_allow_transcoding,
+		  cfg_mgcp_allow_transcoding_cmd,
+		  "allow-transcoding", "Allow transcoding\n")
+{
+	vty_out(vty, "%% Deprecated 'allow-transcoding' config no longer has any effect%s", VTY_NEWLINE);
+	return CMD_SUCCESS;
+}
+
+DEFUN_DEPRECATED(cfg_mgcp_no_allow_transcoding,
+		 cfg_mgcp_no_allow_transcoding_cmd,
+		 "no allow-transcoding", NO_STR "Allow transcoding\n")
+{
+	vty_out(vty, "%% Deprecated 'no allow-transcoding' config no longer has any effect%s", VTY_NEWLINE);
+	return CMD_SUCCESS;
+}
+
 DEFUN_DEPRECATED(cfg_mgcp_sdp_payload_number,
       cfg_mgcp_sdp_payload_number_cmd,
       "sdp audio-payload number <0-255>",
       SDP_STR AUDIO_STR "Number\n" "Payload number\n")
 {
+	vty_out(vty, "%% Deprecated 'sdp audio-payload number <0-255>' config no longer has any effect%s", VTY_NEWLINE);
 	return CMD_SUCCESS;
 }
 
@@ -742,6 +725,7 @@ DEFUN_DEPRECATED(cfg_mgcp_sdp_payload_name,
       "sdp audio-payload name NAME",
       SDP_STR AUDIO_STR "Name\n" "Payload name\n")
 {
+	vty_out(vty, "%% Deprecated 'sdp audio-payload name NAME' config no longer has any effect%s", VTY_NEWLINE);
 	return CMD_SUCCESS;
 }
 
@@ -802,6 +786,7 @@ DEFUN_DEPRECATED(cfg_mgcp_loop,
 		 "loop (0|1)",
 		 "Loop audio for all endpoints on main trunk\n" "Don't Loop\n" "Loop\n")
 {
+	vty_out(vty, "%% Deprecated 'loop (0|1)' config no longer has any effect%s", VTY_NEWLINE);
 	return CMD_SUCCESS;
 }
 
@@ -1066,30 +1051,17 @@ static int config_write_trunk(struct vty *vty)
 				VTY_NEWLINE);
 		} else
 			vty_out(vty, "  no rtp-patch%s", VTY_NEWLINE);
-		if (trunk->audio_fmtp_extra)
-			vty_out(vty, "   sdp audio fmtp-extra %s%s",
-				trunk->audio_fmtp_extra, VTY_NEWLINE);
-		vty_out(vty, "  %sallow-transcoding%s",
-			trunk->no_audio_transcoding ? "no " : "", VTY_NEWLINE);
 	}
 
 	return CMD_SUCCESS;
 }
 
-DEFUN_USRATTR(cfg_trunk_sdp_fmtp_extra,
+DEFUN_DEPRECATED(cfg_trunk_sdp_fmtp_extra,
 	      cfg_trunk_sdp_fmtp_extra_cmd,
-	      X(MGW_CMD_ATTR_NEWCONN),
 	      "sdp audio fmtp-extra .NAME",
-	      "Add extra fmtp for the SDP file\n" "Audio\n" "Fmtp-extra\n"
-	      "Extra Information\n")
+	      SDP_STR AUDIO_STR "Deprecated, without effect since osmo-mgw v1.13\n" "Deprecated, without effect\n")
 {
-	struct mgcp_trunk *trunk = vty->index;
-	char *txt = argv_concat(argv, argc, 0);
-	if (!txt)
-		return CMD_WARNING;
-
-	osmo_talloc_replace_string(g_cfg, &trunk->audio_fmtp_extra, txt);
-	talloc_free(txt);
+	vty_out(vty, "%% deprecated: the config option 'sdp audio fmtp-extra' has been removed.%s", VTY_NEWLINE);
 	return CMD_SUCCESS;
 }
 
@@ -1098,6 +1070,7 @@ DEFUN_DEPRECATED(cfg_trunk_payload_number,
       "sdp audio-payload number <0-255>",
       SDP_STR AUDIO_STR "Number\n" "Payload Number\n")
 {
+	vty_out(vty, "%% Deprecated 'sdp audio-payload number <0-255>' config no longer has any effect%s", VTY_NEWLINE);
 	return CMD_SUCCESS;
 }
 
@@ -1110,6 +1083,7 @@ DEFUN_DEPRECATED(cfg_trunk_payload_name,
       "sdp audio-payload name NAME",
       SDP_STR AUDIO_STR "Payload\n" "Payload Name\n")
 {
+	vty_out(vty, "%% Deprecated 'sdp audio-payload name NAME' config no longer has any effect%s", VTY_NEWLINE);
 	return CMD_SUCCESS;
 }
 
@@ -1122,6 +1096,7 @@ DEFUN_DEPRECATED(cfg_trunk_loop,
 		 "loop (0|1)",
 		 "Loop audio for all endpoints on this trunk\n" "Don't Loop\n" "Loop\n")
 {
+	vty_out(vty, "%% Deprecated 'loop (0|1)' config no longer has any effect%s", VTY_NEWLINE);
 	return CMD_SUCCESS;
 }
 
@@ -1319,23 +1294,19 @@ DEFUN_ATTR(cfg_trunk_no_rtp_keepalive,
 	return CMD_SUCCESS;
 }
 
-DEFUN_USRATTR(cfg_trunk_allow_transcoding,
-	      cfg_trunk_allow_transcoding_cmd,
-	      X(MGW_CMD_ATTR_NEWCONN),
-	      "allow-transcoding", "Allow transcoding\n")
+DEFUN_DEPRECATED(cfg_trunk_allow_transcoding,
+		 cfg_trunk_allow_transcoding_cmd,
+		 "allow-transcoding", "Allow transcoding\n")
 {
-	struct mgcp_trunk *trunk = vty->index;
-	trunk->no_audio_transcoding = 0;
+	vty_out(vty, "%% Deprecated 'allow-transcoding' config no longer has any effect%s", VTY_NEWLINE);
 	return CMD_SUCCESS;
 }
 
-DEFUN_USRATTR(cfg_trunk_no_allow_transcoding,
-	      cfg_trunk_no_allow_transcoding_cmd,
-	      X(MGW_CMD_ATTR_NEWCONN),
-	      "no allow-transcoding", NO_STR "Allow transcoding\n")
+DEFUN_DEPRECATED(cfg_trunk_no_allow_transcoding,
+		 cfg_trunk_no_allow_transcoding_cmd,
+		 "no allow-transcoding", NO_STR "Allow transcoding\n")
 {
-	struct mgcp_trunk *trunk = vty->index;
-	trunk->no_audio_transcoding = 1;
+	vty_out(vty, "%% Deprecated 'no allow-transcoding' config no longer has any effect%s", VTY_NEWLINE);
 	return CMD_SUCCESS;
 }
 

src/libosmo-sdp/Makefile.am

@@ -0,0 +1,24 @@
+AM_CPPFLAGS = \
+	$(all_includes) \
+	-I$(top_srcdir)/include \
+	-I$(top_builddir) \
+	$(NULL)
+
+AM_CFLAGS = \
+	-Wall \
+	$(LIBOSMOCORE_CFLAGS) \
+	$(TALLOC_CFLAGS) \
+	$(NULL)
+
+noinst_LTLIBRARIES = \
+	libosmo-sdp.la \
+	$(NULL)
+
+libosmo_sdp_la_SOURCES = \
+	fmtp.c \
+	$(NULL)
+
+libosmo_sdp_la_LIBADD = \
+	$(LIBOSMOCORE_LIBS) \
+	$(TALLOC_LIBS) \
+	$(NULL)

src/libosmo-sdp/fmtp.c

@@ -0,0 +1,150 @@
+/*
+ * (C) 2023-2024 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 <string.h>
+#include <ctype.h>
+#include <osmocom/core/utils.h>
+#include <osmocom/core/logging.h>
+
+#include <osmocom/sdp/sdp_strings.h>
+#include <osmocom/sdp/fmtp.h>
+
+/* End of current fmtp parameter. Return a pointer to the next ';' character, if present, or the terminating '\0'. */
+static const char *osmo_sdp_fmtp_end(const char *fmtp)
+{
+	if (!fmtp)
+		return NULL;
+	for (; *fmtp && *fmtp != ';'; fmtp++);
+	return fmtp;
+}
+
+/* Start of next fmtp parameter. Return a pointer to the first character of the next fmtp parameter's name, or the
+ * terminating '\0'. */
+static const char *osmo_sdp_fmtp_next(const char *fmtp)
+{
+	if (!fmtp)
+		return NULL;
+	fmtp = osmo_sdp_fmtp_end(fmtp);
+	for (; *fmtp && (*fmtp == ';' || isspace(*fmtp)); fmtp++);
+	return fmtp;
+}
+
+/*! Parse a given SDP fmtp value string, returning the value of a specific option, if present.
+ *
+ * Example:
+ *
+ *   const char *fmtp_vals = "octet-align=1;mode-set=0,2,4,7";
+ *
+ *   char mode_set_str[23];
+ *   if (osmo_sdp_fmtp_get_val(mode_set_str, sizeof(mode_set_str), fmtp_vals, "mode-set")) {
+ *           // option 'mode-set' is present, now mode_set_str == "0,2,4,7"
+ *           use_modeset(mode_set_str);
+ *   } else {
+ *           // if 'mode-set' were not present...
+ *           use_modeset(MY_DEFAULT_MODESET);
+ *   }
+ *
+ * \param[out] val  Buffer to write the option's value to.
+ * \param[in] val_size  Space available in val.
+ * \param[in] fmtp  fmtp value string to parse -- must not contain the "a=fmtp:N " prefix, only the value part.
+ * \param[in] option_name  Which fmtp option to get the value for.
+ * \return true when the option was found, false when it was not present.
+ */
+bool osmo_sdp_fmtp_get_val(char *val, size_t val_size, const char *fmtp, const char *option_name)
+{
+	const char *pos = fmtp;
+	const char *end;
+	int option_name_len = strlen(option_name);
+	for (; pos && *pos; pos = osmo_sdp_fmtp_next(pos)) {
+		if (!osmo_str_startswith(pos, option_name))
+			continue;
+		pos += option_name_len;
+		if (*pos != '=')
+			continue;
+		pos++;
+		break;
+	}
+
+	if (!pos || !*pos)
+		return false;
+
+	end = osmo_sdp_fmtp_end(pos);
+	OSMO_ASSERT(end);
+	if (val && val_size)
+		osmo_strlcpy(val, pos, OSMO_MIN(val_size, end - pos + 1));
+	return true;
+}
+
+/*! Parse a given SDP fmtp value string, returning the value of a specific integer option, if present.
+ *
+ * Example:
+ *
+ *   const char *fmtp_vals = "octet-align=1;mode-set=0,2,4,7";
+ *   bool oa = osmo_sdp_fmtp_get_int(fmtp_vals, OSMO_SDP_AMR_OCTET_ALIGN_NAME, 1);
+ *
+ * \param[in] fmtp  fmtp value string to parse -- must not contain the "a=fmtp:N " prefix, only the value part.
+ * \param[in] option_name  Which fmtp option to get the value for.
+ * \param[in] default_value  If option_name is not present or cannot be parsed as integer, return this instead.
+ * \return the integer value when the option was found and actually an integer, default_value otherwise.
+ */
+int64_t osmo_sdp_fmtp_get_int(const char *fmtp, const char *option_name, int64_t default_value)
+{
+	char val[128];
+	if (!osmo_sdp_fmtp_get_val(val, sizeof(val), fmtp, option_name))
+		return default_value;
+	if (!val[0])
+		return default_value;
+	int64_t i;
+	if (osmo_str_to_int64(&i, val, 10, INT64_MIN, INT64_MAX)) {
+		/* error parsing number */
+		return default_value;
+	}
+	return i;
+}
+
+/*! Return true if octet-align is present and set to 1 in the given AMR related fmtp value.
+ * Default to octet-align=0, i.e. bandwidth-efficient mode.
+ *
+ * See RFC4867 "RTP Payload Format for AMR and AMR-WB" sections "8.1. AMR Media Type Registration" and "8.2. AMR-WB
+ * Media Type Registration":
+ *
+ *    octet-align: Permissible values are 0 and 1.  If 1, octet-align
+ *                 operation SHALL be used.  If 0 or if not present,
+ *                 bandwidth-efficient operation is employed.
+ *
+ * https://tools.ietf.org/html/rfc4867
+ */
+bool osmo_sdp_fmtp_amr_is_octet_aligned(const char *fmtp)
+{
+	return osmo_sdp_fmtp_get_int(fmtp, OSMO_SDP_STR_AMR_OCTET_ALIGN, 0) == 1;
+}
+
+static void strip_whitespace(char *str)
+{
+	char *i = str;
+	char *o = str;
+	for (; *i; i++, o++) {
+		while (isspace(*i))
+			i++;
+		*o = *i;
+		if (!*i)
+			break;
+	}
+}

src/osmo-mgw/Makefile.am

@@ -25,12 +25,6 @@ osmo_mgw_SOURCES = \
 	$(NULL)
 
 osmo_mgw_LDADD = \
-	$(top_builddir)/src/libosmo-mgcp/libosmo-mgcp.a \
-	$(LIBOSMOCORE_LIBS) \
-	$(LIBOSMOVTY_LIBS) \
-	$(LIBOSMOGSM_LIBS) \
+	$(top_builddir)/src/libosmo-mgcp/libosmo-mgcp.la \
 	$(LIBOSMOCTRL_LIBS) \
-	$(LIBOSMONETIF_LIBS) \
-	$(LIBOSMOABIS_LIBS) \
-	$(LIBOSMOTRAU_LIBS) \
 	$(NULL)

src/osmo-mgw/mgw_main.c

@@ -41,7 +41,6 @@
 #include <osmocom/mgcp/debug.h>
 #include <osmocom/mgcp/mgcp_endp.h>
 #include <osmocom/mgcp/mgcp_trunk.h>
-#include <osmocom/mgcp/mgcp_ctrl.h>
 
 #include <osmocom/core/application.h>
 #include <osmocom/core/msgb.h>
@@ -51,7 +50,7 @@
 #include <osmocom/core/rate_ctr.h>
 #include <osmocom/core/logging.h>
 #include <osmocom/core/socket.h>
-
+#include <osmocom/ctrl/control_if.h>
 #include <osmocom/ctrl/control_vty.h>
 
 #include <osmocom/vty/telnet_interface.h>
@@ -83,7 +82,7 @@ static int daemonize = 0;
 
 const char *osmomgw_copyright =
 	"Copyright (C) 2009-2010 Holger Freyther and On-Waves\r\n"
-	"Copyright (C) 2017 by sysmocom s.f.m.c. GmbH <info@sysmocom.de>\r\n"
+	"Copyright (C) 2017-2022 by sysmocom s.f.m.c. GmbH\r\n"
 	"Contributions by Pablo Neira Ayuso, Jacob Erlbeck, Neels Hofmeyr\r\n"
 	"Philipp Maier\r\n\r\n"
 	"License AGPLv3+: GNU AGPL version 3 or later <http://gnu.org/licenses/agpl-3.0.html>\r\n"
@@ -361,12 +360,11 @@ int main(int argc, char **argv)
 		return rc;
 
 	/* start telnet after reading config for vty_get_bind_addr() */
-	rc = telnet_init_dynif(tall_mgw_ctx, NULL,
-			       vty_get_bind_addr(), OSMO_VTY_PORT_MGW);
+	rc = telnet_init_default(tall_mgw_ctx, NULL, OSMO_VTY_PORT_MGW);
 	if (rc < 0)
 		return rc;
 
-	cfg->ctrl = mgw_ctrl_interface_setup(cfg, ctrl_vty_get_bind_addr(), OSMO_CTRL_PORT_MGW);
+	cfg->ctrl = ctrl_interface_setup(cfg, OSMO_CTRL_PORT_MGW, NULL);
 	if (!cfg->ctrl) {
 		fprintf(stderr, "Failed to init the control interface on %s:%u. Exiting\n",
 			ctrl_vty_get_bind_addr(), OSMO_CTRL_PORT_MGW);

tests/Makefile.am

@@ -1,6 +1,7 @@
 SUBDIRS = \
 	mgcp_client \
 	mgcp \
+	sdp \
 	$(NULL)
 
 # The `:;' works around a Bash 3.2 bug when the output is not writeable.
@@ -34,11 +35,11 @@ DISTCLEANFILES = \
 	$(NULL)
 
 if ENABLE_EXT_TESTS
-python-tests: $(BUILT_SOURCES)
+python-tests: $(top_builddir)/src/osmo-mgw/osmo-mgw
 	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
 

tests/mgcp/Makefile.am

@@ -18,6 +18,7 @@ AM_CFLAGS = \
 
 AM_LDFLAGS = \
 	$(COVERAGE_LDFLAGS) \
+	-no-install \
 	$(NULL)
 
 EXTRA_DIST = \
@@ -33,7 +34,7 @@ mgcp_test_SOURCES = \
 	$(NULL)
 
 mgcp_test_LDADD = \
-	$(top_builddir)/src/libosmo-mgcp/libosmo-mgcp.a \
+	$(top_builddir)/src/libosmo-mgcp/libosmo-mgcp.la \
 	$(LIBOSMOCORE_LIBS) \
 	$(LIBOSMOVTY_LIBS) \
 	$(LIBOSMOGSM_LIBS) \
@@ -44,3 +45,6 @@ mgcp_test_LDADD = \
 	$(LIBOSMONETIF_LIBS) \
 	-lm  \
 	$(NULL)
+
+update_exp:
+	$(builddir)/mgcp_test >$(srcdir)/mgcp_test.ok

tests/mgcp/mgcp_test.c

@@ -77,6 +77,8 @@ static void test_strline(void)
 #define AUEP1_RET "500 158663169 FAIL\r\n"
 #define AUEP2	"AUEP 18983213 ds/e1-2/1@mgw MGCP 1.0\r\n"
 #define AUEP2_RET "500 18983213 FAIL\r\n"
+#define AUEP_NULL "AUEP 18983215 null@mgw MGCP 1.0\r\n"
+#define AUEP_NULL_RET "200 18983215 OK\r\n"
 #define EMPTY	"\r\n"
 #define EMPTY_RET NULL
 #define SHORT	"CRCX \r\n"
@@ -125,7 +127,6 @@ static void test_strline(void)
 	"t=0 0\r\n" \
 	"m=audio 16006 RTP/AVP 97\r\n" \
 	"a=rtpmap:97 GSM-EFR/8000\r\n" \
-	"a=fmtp:126 0/1/2\r\n" \
 	"a=ptime:40\r\n"
 
 #define MDCX4_ADDR0000 \
@@ -274,6 +275,12 @@ static void test_strline(void)
 
 #define MDCX_TOO_LONG_CI_RET "510 18983224 FAIL\r\n"
 
+#define MDCX_NULL \
+	"MDCX 9 null@mgw MGCP 1.0\r\n" \
+	"I: %s\n"
+
+#define MDCX_NULL_RET "502 9 FAIL\r\n"
+
 #define SHORT2	"CRCX 1"
 #define SHORT2_RET "510 000000 FAIL\r\n"
 #define SHORT3	"CRCX 1 1@mgw"
@@ -328,7 +335,6 @@ static void test_strline(void)
 	"t=0 0\r\n" \
 	"m=audio 16006 RTP/AVP 97\r\n" \
 	"a=rtpmap:97 GSM-EFR/8000\r\n" \
-	"a=fmtp:126 0/1/2\r\n" \
 	"a=ptime:40\r\n"
 
 #define CRCX_ZYN \
@@ -392,6 +398,13 @@ static void test_strline(void)
  #define DLCX_RET_OSMUX DLCX_RET \
 	"X-Osmo-CP: EC TI=0, TO=0\r\n"
 
+#define DLCX_NULL \
+	"DLCX 8 null@mgw MGCP 1.0\r\n" \
+	"I: %s\r\n" \
+	"C: 2\r\n"
+
+#define DLCX_NULL_RET "502 8 FAIL\r\n"
+
 #define RQNT \
 	"RQNT 186908780 1@mgw MGCP 1.0\r\n" \
 	"X: B244F267488\r\n" \
@@ -405,6 +418,13 @@ static void test_strline(void)
 #define RQNT1_RET "200 186908780 OK\r\n"
 #define RQNT2_RET "200 186908781 OK\r\n"
 
+#define RQNT_NULL \
+	"RQNT 186908782 null@mgw MGCP 1.0\r\n" \
+	"X: B244F267488\r\n" \
+	"S: D/9\r\n"
+
+#define RQNT_NULL_RET "502 186908782 FAIL\r\n"
+
 #define PTYPE_IGNORE 0		/* == default initializer */
 #define PTYPE_NONE 128
 #define PTYPE_NYI  PTYPE_NONE
@@ -530,7 +550,7 @@ static void test_strline(void)
 	"t=0 0\r\n" \
 	"m=audio 16012 RTP/AVP 111\r\n" \
 	"a=rtpmap:111 AMR/8000/1\r\n" \
-	"a=fmtp:111 octet-align=1\r\n" \
+	"a=fmtp:111 mode-change-capability=2; octet-align=1\r\n" \
 	"a=ptime:20\r\n"
 
 #define CRCX_NO_LCO_NO_SDP_RET \
@@ -545,12 +565,25 @@ static void test_strline(void)
 	"m=audio 16008 RTP/AVP 0\r\n" \
 	"a=ptime:20\r\n"
 
+#define CRCX_NULL \
+	"CRCX 2 null@mgw MGCP 1.0\r\n" \
+	"m: recvonly\r\n" \
+	"C: 2\r\n" \
+	"L: p:20\r\n" \
+	"\r\n" \
+	"v=0\r\n" \
+	"c=IN IP4 123.12.12.123\r\n" \
+	"m=audio 5904 RTP/AVP 97\r\n" \
+	"a=rtpmap:97 GSM-EFR/8000\r\n" \
+	"a=ptime:40\r\n"
+
+#define CRCX_NULL_RET "502 2 FAIL\r\n"
+
 struct mgcp_test {
 	const char *name;
 	const char *req;
 	const char *exp_resp;
 	int ptype;
-	const char *extra_fmtp;
 };
 
 static const struct mgcp_test tests[] = {
@@ -578,14 +611,18 @@ static const struct mgcp_test tests[] = {
 	{"RQNT1", RQNT, RQNT1_RET},
 	{"RQNT2", RQNT2, RQNT2_RET},
 	{"DLCX", DLCX, DLCX_RET, PTYPE_IGNORE},
-	{"CRCX", CRCX, CRCX_FMTP_RET, 97,.extra_fmtp = "a=fmtp:126 0/1/2"},
-	{"MDCX3", MDCX3, MDCX3_FMTP_RET, PTYPE_NONE,.extra_fmtp =
-	 "a=fmtp:126 0/1/2"},
-	{"DLCX", DLCX, DLCX_RET, PTYPE_IGNORE,.extra_fmtp = "a=fmtp:126 0/1/2"},
+	{"CRCX", CRCX, CRCX_FMTP_RET, 97},
+	{"MDCX3", MDCX3, MDCX3_FMTP_RET, PTYPE_NONE},
+	{"DLCX", DLCX, DLCX_RET, PTYPE_IGNORE},
 	{"CRCX", CRCX_NO_LCO_NO_SDP, CRCX_NO_LCO_NO_SDP_RET, 97},
 	{"CRCX", CRCX_X_OSMO_IGN, CRCX_X_OSMO_IGN_RET, 97},
 	{"MDCX_TOO_LONG_CI", MDCX_TOO_LONG_CI, MDCX_TOO_LONG_CI_RET},
 	{"CRCX", CRCX_AMR_WITH_FMTP, CRCX_AMR_WITH_FMTP_RET},
+	{"AUEP_NULL", AUEP_NULL, AUEP_NULL_RET},
+	{"CRCX_NULL", CRCX_NULL, CRCX_NULL_RET},
+	{"MDCX_NULL", MDCX_NULL, MDCX_NULL_RET},
+	{"DLCX_NULL", DLCX_NULL, DLCX_NULL_RET},
+	{"RQNT_NULL", RQNT_NULL, RQNT_NULL_RET},
 };
 
 static const struct mgcp_test retransmit[] = {
@@ -790,9 +827,6 @@ static void test_messages(void)
 
 		dummy_packets = 0;
 
-		osmo_talloc_replace_string(cfg, &trunk->audio_fmtp_extra,
-					   t->extra_fmtp);
-
 		inp = create_msg(t->req, last_conn_id);
 		msg = mgcp_handle_message(cfg, inp);
 		msgb_free(inp);
@@ -804,6 +838,7 @@ static void test_messages(void)
 			}
 		} else if (check_response(msg->data, t->exp_resp) != 0) {
 			printf("%s failed.\n", t->name);
+			fflush(stdout);
 			OSMO_ASSERT(false);
 		}
 
@@ -838,7 +873,7 @@ static void test_messages(void)
 				if (endp->local_options.pkt_period_min ||
 				    endp->local_options.pkt_period_max)
 					printf
-					    ("Requested packetetization period: "
+					    ("Requested packetization period: "
 					     "%d-%d\n",
 					     endp->local_options.pkt_period_min,
 					     endp->
@@ -1467,7 +1502,6 @@ static void test_multilple_codec(void)
 	/* Allocate 5@mgw and let osmo-mgw pick a codec from the list */
 	last_endpoint[0] = '\0';
 	inp = create_msg(CRCX_MULT_GSM_EXACT, NULL);
-	trunk->no_audio_transcoding = 1;
 	resp = mgcp_handle_message(cfg, inp);
 	OSMO_ASSERT(get_conn_id_from_response(resp->data, conn_id,
 					      sizeof(conn_id)) == 0);
@@ -1511,7 +1545,6 @@ static void test_multilple_codec(void)
 
 	last_endpoint[0] = '\0';
 	inp = create_msg(CRCX_MULT_GSM_EXACT, NULL);
-	trunk->no_audio_transcoding = 0;
 	resp = mgcp_handle_message(cfg, inp);
 	OSMO_ASSERT(get_conn_id_from_response(resp->data, conn_id,
 					      sizeof(conn_id)) == 0);
@@ -1632,7 +1665,8 @@ static void test_osmux_cid(void)
 
 	for (i = 0; i < 256; ++i) {
 		id = osmux_cid_pool_get_next();
-		OSMO_ASSERT(id == i);
+		/* We called osmux_cid_pool_get_next() above, so next CID is i+1. */
+		OSMO_ASSERT(id == ((i + 1) & 0xff));
 		OSMO_ASSERT(osmux_cid_pool_count_used() == i + 1);
 	}
 
@@ -1768,26 +1802,25 @@ static const struct mgcp_codec_param amr_param_octet_aligned_unset = {
 	.amr_octet_aligned_present = false,
 };
 
-struct testcase_mgcp_codec_pt_translate_codec {
+struct testcase_mgcp_codec_decide_codec {
 	int payload_type;
 	const char *audio_name;
 	const struct mgcp_codec_param *param;
 	int expect_rc;
 };
 
-struct testcase_mgcp_codec_pt_translate_expect {
-	bool end;
+struct testcase_mgcp_codec_decide_expect {
 	int payload_type_map[2];
 };
 
-struct testcase_mgcp_codec_pt_translate {
+struct testcase_mgcp_codec_decide {
 	const char *descr;
 	/* two conns on an endpoint, each with N configured codecs */
-	struct testcase_mgcp_codec_pt_translate_codec codecs[2][10];
-	struct testcase_mgcp_codec_pt_translate_expect expect[32];
+	struct testcase_mgcp_codec_decide_codec codecs[2][10];
+	struct testcase_mgcp_codec_decide_expect expect[2];
 };
 
-static const struct testcase_mgcp_codec_pt_translate test_mgcp_codec_pt_translate_cases[] = {
+static const struct testcase_mgcp_codec_decide test_mgcp_codec_find_convertible_cases[] = {
 	{
 		.descr = "same order, but differing payload type numbers",
 		.codecs = {
@@ -1804,10 +1837,7 @@ static const struct testcase_mgcp_codec_pt_translate test_mgcp_codec_pt_translat
 		},
 		.expect = {
 			{ .payload_type_map = {112, 96}, },
-			{ .payload_type_map = {0, 0}, },
-			{ .payload_type_map = {111, 97} },
-			{ .payload_type_map = {123, -EINVAL} },
-			{ .end = true },
+			{ .payload_type_map = {112, 96}, },
 		},
 	},
 	{
@@ -1825,11 +1855,8 @@ static const struct testcase_mgcp_codec_pt_translate test_mgcp_codec_pt_translat
 			},
 		},
 		.expect = {
-			{ .payload_type_map = {112, 96}, },
 			{ .payload_type_map = {0, 0}, },
-			{ .payload_type_map = {111, 97} },
-			{ .payload_type_map = {123, -EINVAL} },
-			{ .end = true },
+			{ .payload_type_map = {111, 97}, },
 		},
 	},
 	{
@@ -1847,10 +1874,8 @@ static const struct testcase_mgcp_codec_pt_translate test_mgcp_codec_pt_translat
 			},
 		},
 		.expect = {
-			{ .payload_type_map = {96, 97}, },
-			{ .payload_type_map = {97, 96}, },
 			{ .payload_type_map = {0, 0}, },
-			{ .end = true },
+			{ .payload_type_map = {96, 97}, },
 		},
 	},
 	{
@@ -1866,10 +1891,8 @@ static const struct testcase_mgcp_codec_pt_translate test_mgcp_codec_pt_translat
 			},
 		},
 		.expect = {
-			{ .payload_type_map = {112, -EINVAL}, },
-			{ .payload_type_map = {0, -EINVAL}, },
-			{ .payload_type_map = {111, -EINVAL} },
-			{ .end = true },
+			{ .payload_type_map = {-EINVAL, -EINVAL}, },
+			{ .payload_type_map = {-EINVAL, 96}, },
 		},
 	},
 	{
@@ -1886,28 +1909,60 @@ static const struct testcase_mgcp_codec_pt_translate test_mgcp_codec_pt_translat
 		},
 		.expect = {
 			{ .payload_type_map = {112, -EINVAL}, },
-			{ .payload_type_map = {0, -EINVAL}, },
-			{ .payload_type_map = {111, -EINVAL} },
-			{ .end = true },
+			{ .payload_type_map = {-EINVAL, -EINVAL}, },
 		},
 	},
 	{
-		.descr = "test AMR with differing octet-aligned settings",
+		.descr = "test AMR with differing octet-aligned settings (both <-> both)",
+		.codecs = {
+			{
+				{ 111, "AMR/8000", &amr_param_octet_aligned_true, },
+				{ 112, "AMR/8000", &amr_param_octet_aligned_false, },
+			},
+			{
+				{ 122, "AMR/8000", &amr_param_octet_aligned_false, },
+				{ 121, "AMR/8000", &amr_param_octet_aligned_true, },
+			},
+		},
+		.expect = {
+			{ .payload_type_map = {111, 121}, },
+			{ .payload_type_map = {112, 122} },
+		},
+	},
+	{
+		.descr = "test AMR with differing octet-aligned settings (oa <-> both)",
 		.codecs = {
 			{
 				{ 111, "AMR/8000", &amr_param_octet_aligned_true, },
 			},
 			{
 				{ 122, "AMR/8000", &amr_param_octet_aligned_false, },
+				{ 121, "AMR/8000", &amr_param_octet_aligned_true, },
 			},
 		},
 		.expect = {
-			{ .payload_type_map = {111, 122}, },
-			{ .end = true },
+			{ .payload_type_map = {111, 121}, },
+			{ .payload_type_map = {111, 121}, },
 		},
 	},
 	{
-		.descr = "test AMR with missing octet-aligned settings (defaults to 0)",
+		.descr = "test AMR with differing octet-aligned settings (bwe <-> both)",
+		.codecs = {
+			{
+				{ 112, "AMR/8000", &amr_param_octet_aligned_false, },
+			},
+			{
+				{ 122, "AMR/8000", &amr_param_octet_aligned_false, },
+				{ 121, "AMR/8000", &amr_param_octet_aligned_true, },
+			},
+		},
+		.expect = {
+			{ .payload_type_map = {112, 122}, },
+			{ .payload_type_map = {112, 122}, },
+		},
+	},
+	{
+		.descr = "test AMR with missing octet-aligned settings (oa <-> unset)",
 		.codecs = {
 			{
 				{ 111, "AMR/8000", &amr_param_octet_aligned_true, },
@@ -1918,22 +1973,54 @@ static const struct testcase_mgcp_codec_pt_translate test_mgcp_codec_pt_translat
 		},
 		.expect = {
 			{ .payload_type_map = {111, 122}, },
-			{ .end = true },
+			{ .payload_type_map = {111, 122}, },
 		},
 	},
 	{
-		.descr = "test AMR with NULL param (defaults to 0)",
+		.descr = "test AMR with missing octet-aligned settings (bwe <-> unset)",
 		.codecs = {
 			{
-				{ 111, "AMR/8000", &amr_param_octet_aligned_true, },
+				{ 111, "AMR/8000", &amr_param_octet_aligned_false, },
+			},
+			{
+				{ 122, "AMR/8000", &amr_param_octet_aligned_unset, },
+			},
+		},
+		.expect = {
+			{ .payload_type_map = {111, 122}, },
+			{ .payload_type_map = {111, 122}, },
+		},
+	},
+	{
+		.descr = "test AMR with NULL param (oa <-> null)",
+		.codecs = {
+			{
+				{ 112, "AMR/8000", &amr_param_octet_aligned_true, },
 			},
 			{
 				{ 122, "AMR/8000", NULL, },
 			},
 		},
 		.expect = {
-			{ .payload_type_map = {111, 122}, },
-			{ .end = true },
+			/* Note: Both 111, anbd 112 will translate to 122. The translation from 112 */
+			{ .payload_type_map = {112, 122} },
+			{ .payload_type_map = {112, 122}, },
+		},
+	},
+	{
+		.descr = "test AMR with NULL param (bwe <-> null)",
+		.codecs = {
+			{
+				{ 112, "AMR/8000", &amr_param_octet_aligned_false, },
+			},
+			{
+				{ 122, "AMR/8000", NULL, },
+			},
+		},
+		.expect = {
+			/* Note: Both 111, anbd 112 will translate to 122. The translation from 112 */
+			{ .payload_type_map = {112, 122} },
+			{ .payload_type_map = {112, 122}, },
 		},
 	},
 	{
@@ -1951,11 +2038,8 @@ static const struct testcase_mgcp_codec_pt_translate test_mgcp_codec_pt_translat
 			},
 		},
 		.expect = {
-			{ .payload_type_map = {112, 96}, },
 			{ .payload_type_map = {0, 0}, },
-			{ .payload_type_map = {111, 97} },
-			{ .payload_type_map = {123, -EINVAL} },
-			{ .end = true },
+			{ .payload_type_map = {111, 97}, },
 		},
 	},
 	{
@@ -1973,11 +2057,8 @@ static const struct testcase_mgcp_codec_pt_translate test_mgcp_codec_pt_translat
 			},
 		},
 		.expect = {
-			{ .payload_type_map = {112, 96}, },
 			{ .payload_type_map = {0, 0}, },
-			{ .payload_type_map = {111, 97} },
-			{ .payload_type_map = {123, -EINVAL} },
-			{ .end = true },
+			{ .payload_type_map = {111, 97}, },
 		},
 	},
 	{
@@ -1995,45 +2076,98 @@ static const struct testcase_mgcp_codec_pt_translate test_mgcp_codec_pt_translat
 		},
 		.expect = {
 			{ .payload_type_map = {111, 121}, },
-			{ .payload_type_map = {112, -EINVAL} },
-			{ .payload_type_map = {113, -EINVAL} },
-			{ .end = true },
+			{ .payload_type_map = {111, 121} },
 		},
 	},
 };
 
-static void test_mgcp_codec_pt_translate(void)
+static bool codec_decision(struct mgcp_conn_rtp *conn, unsigned int index_conn_src, unsigned int index_conn_dst,
+			   const struct testcase_mgcp_codec_decide_expect *expect)
+{
+	bool ok = true;
+	int payload_type_conn_src;
+	int payload_type_conn_dst;
+
+	printf(" - mgcp_codec_decide(&conn[%u], &conn[%u]):\n", index_conn_src, index_conn_dst);
+	if (mgcp_codec_decide(&conn[index_conn_src], &conn[index_conn_dst]) != 0) {
+		if (expect->payload_type_map[index_conn_src] == -EINVAL
+		    && expect->payload_type_map[index_conn_dst] == -EINVAL)
+			printf("    codec decision failed (expected)!\n");
+		else {
+			printf("    ERROR: codec decision failed!\n");
+			ok = false;
+		}
+	} else {
+		printf("    Codec decision result:\n");
+		if (conn[index_conn_src].end.codec) {
+			payload_type_conn_src = conn[index_conn_src].end.codec->payload_type;
+			printf("    conn[%u]: codec:%s, pt:%d\n",
+			       index_conn_src, conn[index_conn_src].end.codec->subtype_name, payload_type_conn_src);
+		} else {
+			payload_type_conn_src = -EINVAL;
+			printf("    conn[%u]: codec:none, pt:none\n", index_conn_src);
+		}
+
+		if (conn[index_conn_dst].end.codec) {
+			payload_type_conn_dst = conn[index_conn_dst].end.codec->payload_type;
+			printf("    conn[%u]: codec:%s, pt:%d\n",
+			       index_conn_dst, conn[index_conn_dst].end.codec->subtype_name,
+			       payload_type_conn_dst);
+		} else {
+			payload_type_conn_dst = -EINVAL;
+			printf("    conn[%u]: codec:none, pt:none\n", index_conn_dst);
+		}
+
+		if (payload_type_conn_src != expect->payload_type_map[index_conn_src]) {
+			printf("    ERROR: conn[%u] unexpected codec decision, expected pt=%d, got pt=%d\n",
+			       index_conn_src, expect->payload_type_map[index_conn_src], payload_type_conn_src);
+			ok = false;
+		}
+
+		if (payload_type_conn_dst != expect->payload_type_map[index_conn_dst]) {
+			printf("    ERROR: conn[%u] unexpected codec decision, expected pt=%d, got pt=%d\n",
+			       index_conn_dst, expect->payload_type_map[index_conn_dst],
+			       payload_type_conn_dst);
+			ok = false;
+		}
+	}
+
+	return ok;
+}
+
+static void test_mgcp_codec_decide(void)
 {
 	int i;
-	bool ok = true;
-	printf("\nTesting mgcp_codec_pt_translate()\n");
+	bool ok_all = true;
+	printf("\nTesting mgcp_codec_find_convertible()\n");
 
-	for (i = 0; i < ARRAY_SIZE(test_mgcp_codec_pt_translate_cases); i++) {
-		const struct testcase_mgcp_codec_pt_translate *t = &test_mgcp_codec_pt_translate_cases[i];
-		struct mgcp_conn_rtp conn[2] = {};
+	for (i = 0; i < ARRAY_SIZE(test_mgcp_codec_find_convertible_cases); i++) {
+		const struct testcase_mgcp_codec_decide *t = &test_mgcp_codec_find_convertible_cases[i];
+		struct mgcp_conn_rtp conn[2] = { };
 		int rc;
 		int conn_i;
 		int c;
+		bool ok = true;
 
 		printf("#%d: %s\n", i, t->descr);
 
+		/* Build testvector (add codecs to conn, set properties etc... */
 		for (conn_i = 0; conn_i < 2; conn_i++) {
 			printf(" - add codecs on conn%d:\n", conn_i);
 			for (c = 0; c < ARRAY_SIZE(t->codecs[conn_i]); c++) {
-				const struct testcase_mgcp_codec_pt_translate_codec *codec = &t->codecs[conn_i][c];
+				const struct testcase_mgcp_codec_decide_codec *codec = &t->codecs[conn_i][c];
 				if (!codec->audio_name)
 					break;
 
-				rc = mgcp_codec_add(&conn[conn_i], codec->payload_type, codec->audio_name, codec->param);
+				rc = mgcp_codec_add(&conn[conn_i], codec->payload_type, codec->audio_name,
+						    codec->param);
 
 				printf("   %2d: %3d %s%s  -> rc=%d\n", c, codec->payload_type, codec->audio_name,
 				       codec->param ?
-					       (codec->param->amr_octet_aligned_present?
-							(codec->param->amr_octet_aligned ?
-								" octet-aligned=1" : " octet-aligned=0")
-							: " octet-aligned=unset")
-						: "",
-						rc);
+				       (codec->param->amr_octet_aligned_present ?
+					(codec->param->amr_octet_aligned ? " octet-aligned=1" : " octet-aligned=0")
+					: " octet-aligned=unset")
+				       : "", rc);
 				if (rc != codec->expect_rc) {
 					printf("     ERROR: expected rc=%d\n", codec->expect_rc);
 					ok = false;
@@ -2043,39 +2177,23 @@ static void test_mgcp_codec_pt_translate(void)
 				printf("    (none)\n");
 		}
 
-		for (c = 0; c < ARRAY_SIZE(t->expect); c++) {
-			const struct testcase_mgcp_codec_pt_translate_expect *expect = &t->expect[c];
-			int result;
+		/* Run codec decision and check expectation */
+		if (!codec_decision(conn, 0, 1, &t->expect[0]))
+			ok = false;
 
-			if (expect->end)
-				break;
+		if (!codec_decision(conn, 1, 0, &t->expect[1]))
+			ok = false;
 
-			result = mgcp_codec_pt_translate(&conn[0], &conn[1], expect->payload_type_map[0]);
-			printf(" - mgcp_codec_pt_translate(conn0, conn1, %d) -> %d\n",
-			       expect->payload_type_map[0], result);
-			if (result != expect->payload_type_map[1]) {
-				printf("     ERROR: expected -> %d\n", expect->payload_type_map[1]);
-				ok = false;
-			}
+		if (ok)
+			printf(" ===> SUCCESS: codec decision as expected!\n");
+		else
+			printf(" ===> FAIL: unexpected codec decision!\n");
 
-			/* If the expected result is an error, don't do reverse map test */
-			if (expect->payload_type_map[1] < 0)
-				continue;
-
-			result = mgcp_codec_pt_translate(&conn[1], &conn[0], expect->payload_type_map[1]);
-			printf(" - mgcp_codec_pt_translate(conn1, conn0, %d) -> %d\n",
-			       expect->payload_type_map[1], result);
-			if (result != expect->payload_type_map[0]) {
-				printf("     ERROR: expected -> %d\n", expect->payload_type_map[0]);
-				ok = false;
-			}
-		}
-
-		for (conn_i = 0; conn_i < 2; conn_i++)
-			mgcp_codec_reset_all(&conn[conn_i]);
+		if (!ok)
+			ok_all = false;
 	}
 
-	OSMO_ASSERT(ok);
+	OSMO_ASSERT(ok_all);
 }
 
 void test_conn_id_matching(void)
@@ -2232,7 +2350,7 @@ int main(int argc, char **argv)
 	test_osmux_cid();
 	test_get_lco_identifier();
 	test_check_local_cx_options(ctx);
-	test_mgcp_codec_pt_translate();
+	test_mgcp_codec_decide();
 	test_conn_id_matching();
 	test_e1_trunk_nr_from_epname();
 	test_mgcp_is_rtp_dummy_payload();

tests/mgcp/mgcp_test.ok

@@ -525,6 +525,80 @@ Response matches our expectations.
 L: p:20
 
 v=0
+c=IN IP4 123.12.12.123
+m=audio 5904 RTP/AVP 111
+a=rtpmap:111 AMR/8000/1
+a=ptime:20
+a=fmtp:111 mode-change-capability=2; octet-align=1
+
+---------8<---------
+checking response:
+using message with patched conn_id for comparison
+Response matches our expectations.
+(response contains a connection id)
+Dummy packets: 2
+
+================================================
+Testing AUEP_NULL
+creating message from statically defined input:
+---------8<---------
+AUEP 18983215 null@mgw MGCP 1.0
+
+---------8<---------
+checking response:
+using message as statically defined for comparison
+Response matches our expectations.
+(response does not contain a connection id)
+
+================================================
+Testing CRCX_NULL
+creating message from statically defined input:
+---------8<---------
+CRCX 2 null@mgw MGCP 1.0
+m: recvonly
+C: 2
+L: p:20
+
+v=0
+c=IN IP4 123.12.12.123
+m=audio 5904 RTP/AVP 97
+a=rtpmap:97 GSM-EFR/8000
+a=ptime:40
+
+---------8<---------
+checking response:
+using message as statically defined for comparison
+Response matches our expectations.
+(response does not contain a connection id)
+
+================================================
+Testing MDCX_NULL
+creating message from statically defined input:
+---------8<---------
+MDCX 9 null@mgw MGCP 1.0
+I: %s
+
+---------8<---------
+checking response:
+using message as statically defined for comparison
+Response matches our expectations.
+(response does not contain a connection id)
+
+================================================
+Testing DLCX_NULL
+creating message from statically defined input:
+---------8<---------
+DLCX 8 null@mgw MGCP 1.0
+I: %s
+C: 2
+
+---------8<---------
+checking response:
+using message as statically defined for comparison
+Response matches our expectations.
+(response does not contain a connection id)
+
+================================================
 Testing RQNT_NULL
 creating message from statically defined input:
 ---------8<---------
@@ -1276,7 +1350,7 @@ p:10, a:PCMU -> p:10, a:PCMU
 Response matches our expectations.
 Testing get_lco_identifier()
 p:10, a:PCMU -> p:10, a:PCMU
-p:10, a:PCMU -> p:10, a:PCMU
+p:10, a:PCMU -> p:10, a:PCMU
 'XXXX, p:10, a:PCMU' -> 'p:10, a:PCMU'
 'XXXX,p:10,a:PCMU' -> 'p:10,a:PCMU'
 '10,a:PCMU' -> 'a:PCMU'
@@ -1286,13 +1360,15 @@ Testing mgcp_codec_pt_translate()
 ', a:PCMU' -> 'a:PCMU'
 ' a:PCMU' -> 'a:PCMU'
 '' -> '(null)'
-p10, aPCMU -> (null)
-'10,a :PCMU' -> '(null)'
-
-Testing mgcp_codec_pt_translate()
-#0: same order, but differing payload type numbers
- - add codecs on conn0:
-    0: 112 AMR/8000/1 octet-aligned=1  -> rc=0
+p10, aPCMU -> (null)
+'10,a :PCMU' -> '(null)'
+
+Testing mgcp_codec_find_convertible()
+#0: same order, but differing payload type numbers
+ - add codecs on conn0:
+    0: 112 AMR/8000/1 octet-aligned=1  -> rc=0
+    1:   0 PCMU/8000/1  -> rc=0
+    2: 111 GSM-HR-08/8000/1  -> rc=0
  - add codecs on conn1:
     0:  96 AMR/8000/1 octet-aligned=1  -> rc=0
     1:   0 PCMU/8000/1  -> rc=0
@@ -1302,13 +1378,15 @@ Testing mgcp_codec_pt_translate()
     conn[0]: codec:AMR, pt:112
     conn[1]: codec:AMR, pt:96
  - mgcp_codec_decide(&conn[1], &conn[0]):
- - mgcp_codec_pt_translate(conn1, conn0, 0) -> 0
- - mgcp_codec_pt_translate(conn0, conn1, 111) -> 97
- - mgcp_codec_pt_translate(conn1, conn0, 97) -> 111
- - mgcp_codec_pt_translate(conn0, conn1, 123) -> -22
-#1: different order and different payload type numbers
- - add codecs on conn0:
-    0:   0 PCMU/8000/1  -> rc=0
+    Codec decision result:
+    conn[1]: codec:AMR, pt:96
+    conn[0]: codec:AMR, pt:112
+ ===> SUCCESS: codec decision as expected!
+#1: different order and different payload type numbers
+ - add codecs on conn0:
+    0:   0 PCMU/8000/1  -> rc=0
+    1: 111 GSM-HR-08/8000/1  -> rc=0
+    2: 112 AMR/8000/1 octet-aligned=1  -> rc=0
  - add codecs on conn1:
     0:  97 GSM-HR-08/8000/1  -> rc=0
     1:   0 PCMU/8000/1  -> rc=0
@@ -1318,12 +1396,15 @@ Testing mgcp_codec_pt_translate()
     conn[0]: codec:PCMU, pt:0
     conn[1]: codec:PCMU, pt:0
  - mgcp_codec_decide(&conn[1], &conn[0]):
- - mgcp_codec_pt_translate(conn1, conn0, 0) -> 0
- - mgcp_codec_pt_translate(conn0, conn1, 111) -> 97
- - mgcp_codec_pt_translate(conn1, conn0, 97) -> 111
- - mgcp_codec_pt_translate(conn0, conn1, 123) -> -22
-#2: both sides have the same payload_type numbers assigned to differing codecs
- - add codecs on conn0:
+    Codec decision result:
+    conn[1]: codec:GSM-HR-08, pt:97
+    conn[0]: codec:GSM-HR-08, pt:111
+ ===> SUCCESS: codec decision as expected!
+#2: both sides have the same payload_type numbers assigned to differing codecs
+ - add codecs on conn0:
+    0:   0 PCMU/8000/1  -> rc=0
+    1:  96 GSM-HR-08/8000/1  -> rc=0
+    2:  97 AMR/8000/1 octet-aligned=1  -> rc=0
  - add codecs on conn1:
     0:  97 GSM-HR-08/8000/1  -> rc=0
     1:   0 PCMU/8000/1  -> rc=0
@@ -1331,9 +1412,13 @@ Testing mgcp_codec_pt_translate()
  - mgcp_codec_decide(&conn[0], &conn[1]):
     Codec decision result:
     conn[0]: codec:PCMU, pt:0
- - mgcp_codec_pt_translate(conn0, conn1, 96) -> 97
- - mgcp_codec_pt_translate(conn1, conn0, 97) -> 96
- - mgcp_codec_pt_translate(conn0, conn1, 97) -> 96
+    conn[1]: codec:PCMU, pt:0
+ - mgcp_codec_decide(&conn[1], &conn[0]):
+    Codec decision result:
+    conn[1]: codec:GSM-HR-08, pt:97
+    conn[0]: codec:GSM-HR-08, pt:96
+ ===> SUCCESS: codec decision as expected!
+#3: conn0 has no codecs
  - add codecs on conn0:
     (none)
  - add codecs on conn1:
@@ -1341,31 +1426,116 @@ Testing mgcp_codec_pt_translate()
     1:   0 PCMU/8000/1  -> rc=0
     2:  97 GSM-HR-08/8000/1  -> rc=0
  - mgcp_codec_decide(&conn[0], &conn[1]):
-    0:  96 AMR/8000/1 octet-aligned=1  -> rc=0
-    1:   0 PCMU/8000/1  -> rc=0
-    2:  97 GSM-HR-08/8000/1  -> rc=0
- - mgcp_codec_pt_translate(conn0, conn1, 112) -> -22
+    codec decision failed (expected)!
+ - mgcp_codec_decide(&conn[1], &conn[0]):
+    Codec decision result:
+    conn[1]: codec:AMR, pt:96
+    conn[0]: codec:none, pt:none
+ ===> SUCCESS: codec decision as expected!
+#4: conn1 has no codecs
+ - add codecs on conn0:
+    0: 112 AMR/8000/1 octet-aligned=1  -> rc=0
+    1:   0 PCMU/8000/1  -> rc=0
+    2: 111 GSM-HR-08/8000/1  -> rc=0
+ - add codecs on conn1:
+    (none)
+ - mgcp_codec_decide(&conn[0], &conn[1]):
+    Codec decision result:
+    conn[0]: codec:AMR, pt:112
+    conn[1]: codec:none, pt:none
+ - mgcp_codec_decide(&conn[1], &conn[0]):
+    codec decision failed (expected)!
+ ===> SUCCESS: codec decision as expected!
+#5: test AMR with differing octet-aligned settings (both <-> both)
+ - add codecs on conn0:
+    0: 111 AMR/8000 octet-aligned=1  -> rc=0
+    1: 112 AMR/8000 octet-aligned=0  -> rc=0
  - add codecs on conn1:
     0: 122 AMR/8000 octet-aligned=0  -> rc=0
     1: 121 AMR/8000 octet-aligned=1  -> rc=0
  - mgcp_codec_decide(&conn[0], &conn[1]):
-    0: 112 AMR/8000/1 octet-aligned=1  -> rc=0
-    1:   0 PCMU/8000/1  -> rc=0
-    2: 111 GSM-HR-08/8000/1  -> rc=0
+    Codec decision result:
+    conn[0]: codec:AMR, pt:111
+    conn[1]: codec:AMR, pt:121
+ - mgcp_codec_decide(&conn[1], &conn[0]):
+    Codec decision result:
+    conn[1]: codec:AMR, pt:122
+    conn[0]: codec:AMR, pt:112
+ ===> SUCCESS: codec decision as expected!
+#6: test AMR with differing octet-aligned settings (oa <-> both)
+ - add codecs on conn0:
+    0: 111 AMR/8000 octet-aligned=1  -> rc=0
+ - add codecs on conn1:
+    0: 122 AMR/8000 octet-aligned=0  -> rc=0
+    1: 121 AMR/8000 octet-aligned=1  -> rc=0
+ - mgcp_codec_decide(&conn[0], &conn[1]):
+    Codec decision result:
+    conn[0]: codec:AMR, pt:111
+    conn[1]: codec:AMR, pt:121
+ - mgcp_codec_decide(&conn[1], &conn[0]):
+    Codec decision result:
+    conn[1]: codec:AMR, pt:121
+    conn[0]: codec:AMR, pt:111
+ ===> SUCCESS: codec decision as expected!
+#7: test AMR with differing octet-aligned settings (bwe <-> both)
+ - add codecs on conn0:
+    0: 112 AMR/8000 octet-aligned=0  -> rc=0
  - add codecs on conn1:
     0: 122 AMR/8000 octet-aligned=0  -> rc=0
     1: 121 AMR/8000 octet-aligned=1  -> rc=0
  - mgcp_codec_decide(&conn[0], &conn[1]):
- - mgcp_codec_pt_translate(conn0, conn1, 111) -> -22
-#5: test AMR with differing octet-aligned settings
- - add codecs on conn0:
+    Codec decision result:
+    conn[0]: codec:AMR, pt:112
+    conn[1]: codec:AMR, pt:122
+ - mgcp_codec_decide(&conn[1], &conn[0]):
+    Codec decision result:
+    conn[1]: codec:AMR, pt:122
+    conn[0]: codec:AMR, pt:112
+ ===> SUCCESS: codec decision as expected!
+#8: test AMR with missing octet-aligned settings (oa <-> unset)
+ - add codecs on conn0:
     0: 111 AMR/8000 octet-aligned=1  -> rc=0
- - add codecs on conn1:
+ - add codecs on conn1:
+    0: 122 AMR/8000 octet-aligned=unset  -> rc=0
+ - mgcp_codec_decide(&conn[0], &conn[1]):
+    Codec decision result:
+    conn[0]: codec:AMR, pt:111
+    conn[1]: codec:AMR, pt:122
+ - mgcp_codec_decide(&conn[1], &conn[0]):
+    Codec decision result:
+    conn[1]: codec:AMR, pt:122
+    conn[0]: codec:AMR, pt:111
+ ===> SUCCESS: codec decision as expected!
+#9: test AMR with missing octet-aligned settings (bwe <-> unset)
+ - add codecs on conn0:
+    0: 111 AMR/8000 octet-aligned=0  -> rc=0
+ - add codecs on conn1:
     0: 122 AMR/8000 octet-aligned=unset  -> rc=0
  - mgcp_codec_decide(&conn[0], &conn[1]):
- - mgcp_codec_pt_translate(conn1, conn0, 122) -> 111
-#6: test AMR with missing octet-aligned settings (defaults to 0)
- - add codecs on conn0:
+    Codec decision result:
+    conn[0]: codec:AMR, pt:111
+    conn[1]: codec:AMR, pt:122
+ - mgcp_codec_decide(&conn[1], &conn[0]):
+    Codec decision result:
+    conn[1]: codec:AMR, pt:122
+    conn[0]: codec:AMR, pt:111
+ ===> SUCCESS: codec decision as expected!
+#10: test AMR with NULL param (oa <-> null)
+ - add codecs on conn0:
+    0: 112 AMR/8000 octet-aligned=1  -> rc=0
+ - add codecs on conn1:
+    0: 122 AMR/8000  -> rc=0
+ - mgcp_codec_decide(&conn[0], &conn[1]):
+    Codec decision result:
+    conn[0]: codec:AMR, pt:112
+    conn[1]: codec:AMR, pt:122
+ - mgcp_codec_decide(&conn[1], &conn[0]):
+    Codec decision result:
+    conn[1]: codec:AMR, pt:122
+    conn[0]: codec:AMR, pt:112
+ ===> SUCCESS: codec decision as expected!
+#11: test AMR with NULL param (bwe <-> null)
+ - add codecs on conn0:
     0: 112 AMR/8000 octet-aligned=0  -> rc=0
  - add codecs on conn1:
     0: 122 AMR/8000  -> rc=0
@@ -1374,14 +1544,16 @@ Testing mgcp_codec_pt_translate()
     conn[0]: codec:AMR, pt:112
     conn[1]: codec:AMR, pt:122
  - mgcp_codec_decide(&conn[1], &conn[0]):
- - add codecs on conn1:
-    0: 122 AMR/8000  -> rc=0
- - mgcp_codec_pt_translate(conn0, conn1, 111) -> 122
- - mgcp_codec_pt_translate(conn1, conn0, 122) -> 111
-#8: match FOO/8000/1 and FOO/8000 as identical, single channel is implicit
- - add codecs on conn0:
-    0:   0 PCMU/8000/1  -> rc=0
-    1: 111 GSM-HR-08/8000/1  -> rc=0
+    Codec decision result:
+    conn[1]: codec:AMR, pt:122
+    conn[0]: codec:AMR, pt:112
+ ===> SUCCESS: codec decision as expected!
+#12: match FOO/8000/1 and FOO/8000 as identical, single channel is implicit
+ - add codecs on conn0:
+    0:   0 PCMU/8000/1  -> rc=0
+    1: 111 GSM-HR-08/8000/1  -> rc=0
+    2: 112 AMR/8000/1 octet-aligned=1  -> rc=0
+ - add codecs on conn1:
     0:  97 GSM-HR-08/8000  -> rc=0
     1:   0 PCMU/8000  -> rc=0
     2:  96 AMR/8000 octet-aligned=1  -> rc=0
@@ -1390,14 +1562,16 @@ Testing mgcp_codec_pt_translate()
     conn[0]: codec:PCMU, pt:0
     conn[1]: codec:PCMU, pt:0
  - mgcp_codec_decide(&conn[1], &conn[0]):
- - mgcp_codec_pt_translate(conn1, conn0, 0) -> 0
- - mgcp_codec_pt_translate(conn0, conn1, 111) -> 97
- - mgcp_codec_pt_translate(conn1, conn0, 97) -> 111
- - mgcp_codec_pt_translate(conn0, conn1, 123) -> -22
-#9: match FOO/8000/1 and FOO as identical, 8k and single channel are implicit
- - add codecs on conn0:
-    0:   0 PCMU/8000/1  -> rc=0
-    1: 111 GSM-HR-08/8000/1  -> rc=0
+    Codec decision result:
+    conn[1]: codec:GSM-HR-08, pt:97
+    conn[0]: codec:GSM-HR-08, pt:111
+ ===> SUCCESS: codec decision as expected!
+#13: match FOO/8000/1 and FOO as identical, 8k and single channel are implicit
+ - add codecs on conn0:
+    0:   0 PCMU/8000/1  -> rc=0
+    1: 111 GSM-HR-08/8000/1  -> rc=0
+    2: 112 AMR/8000/1 octet-aligned=1  -> rc=0
+ - add codecs on conn1:
     0:  97 GSM-HR-08  -> rc=0
     1:   0 PCMU  -> rc=0
     2:  96 AMR octet-aligned=1  -> rc=0
@@ -1405,10 +1579,15 @@ Testing mgcp_codec_pt_translate()
     Codec decision result:
     conn[0]: codec:PCMU, pt:0
     conn[1]: codec:PCMU, pt:0
- - mgcp_codec_pt_translate(conn0, conn1, 0) -> 0
- - mgcp_codec_pt_translate(conn1, conn0, 0) -> 0
- - mgcp_codec_pt_translate(conn0, conn1, 111) -> 97
- - mgcp_codec_pt_translate(conn1, conn0, 97) -> 111
+ - mgcp_codec_decide(&conn[1], &conn[0]):
+    Codec decision result:
+    conn[1]: codec:GSM-HR-08, pt:97
+    conn[0]: codec:GSM-HR-08, pt:111
+ ===> SUCCESS: codec decision as expected!
+#14: test whether channel number matching is waterproof
+ - add codecs on conn0:
+    0: 111 GSM-HR-08/8000  -> rc=0
+    1: 112 GSM-HR-08/8000/2  -> rc=-22
     2: 113 GSM-HR-08/8000/3  -> rc=-22
  - add codecs on conn1:
     0: 122 GSM-HR-08/8000/2  -> rc=-22

tests/mgcp_client/Makefile.am

@@ -15,6 +15,7 @@ AM_CFLAGS = \
 
 AM_LDFLAGS = \
 	$(COVERAGE_LDFLAGS) \
+	-no-install \
 	$(NULL)
 
 EXTRA_DIST = \

tests/mgcp_client/mgcp_client_test.c

@@ -73,7 +73,7 @@ static struct msgb *from_str(const char *str)
 	return msg;
 }
 
-static struct mgcp_client_conf conf;
+static struct mgcp_client_conf *conf;
 struct mgcp_client *mgcp = NULL;
 
 static int reply_to(mgcp_trans_id_t trans_id, int code, const char *comment,
@@ -107,9 +107,6 @@ void test_response_cb(struct mgcp_response *response, void *priv)
 	printf("  audio_port = %u\n", response->audio_port);
 	printf("  audio_ip = %s\n", response->audio_ip);
 	printf("  ptime = %u\n", response->ptime);
-	printf("  codecs_len = %u\n", response->codecs_len);
-	for(i=0;i<response->codecs_len;i++)
-		printf("  codecs[%u] = %u\n", i, response->codecs[i]);
 	printf("  ptmap_len = %u\n", response->ptmap_len);
 	for(i=0;i<response->ptmap_len;i++) {
 		printf("  ptmap[%u].codec = %u\n", i, response->ptmap[i].codec);
@@ -149,12 +146,11 @@ void test_mgcp_msg(void)
 		.conn_id = "11",
 		.conn_mode = MGCP_CONN_RECV_SEND,
 		.ptime = 20,
-		.codecs[0] = CODEC_GSM_8000_1,
-		.codecs[1] = CODEC_AMR_8000_1,
-		.codecs[2] = CODEC_GSMEFR_8000_1,
-		.codecs_len = 1,
-		.ptmap[0].codec = CODEC_GSMEFR_8000_1,
-		.ptmap[0].pt = 96,
+		.ptmap = {
+			{ .codec = CODEC_GSM_8000_1, .pt = CODEC_GSM_8000_1 },
+			{ .codec = CODEC_AMR_8000_1, .pt = CODEC_AMR_8000_1 },
+			{ .codec = CODEC_GSMEFR_8000_1, .pt = 96 },
+		},
 		.ptmap_len = 1,
 		.x_osmo_ign = MGCP_X_OSMO_IGN_CALLID,
 		.x_osmo_osmux_cid = -1, /* wildcard */
@@ -162,7 +158,7 @@ void test_mgcp_msg(void)
 
 	if (mgcp)
 		talloc_free(mgcp);
-	mgcp = mgcp_client_init(ctx, &conf);
+	mgcp = mgcp_client_init(ctx, conf);
 
 	printf("\n");
 
@@ -179,9 +175,9 @@ void test_mgcp_msg(void)
 	mgcp_msg.presence =
 	    (MGCP_MSG_PRESENCE_ENDPOINT | MGCP_MSG_PRESENCE_CALL_ID |
 	     MGCP_MSG_PRESENCE_CONN_ID | MGCP_MSG_PRESENCE_CONN_MODE);
-	mgcp_msg.codecs_len = 2;
+	mgcp_msg.ptmap_len = 2;
 	msg = mgcp_msg_gen(mgcp, &mgcp_msg);
-	mgcp_msg.codecs_len = 1;
+	mgcp_msg.ptmap_len = 1;
 	printf("%s\n", (char *)msg->data);
 
 	printf("Generated CRCX message (three codecs, one with custom pt):\n");
@@ -189,9 +185,9 @@ void test_mgcp_msg(void)
 	mgcp_msg.presence =
 	    (MGCP_MSG_PRESENCE_ENDPOINT | MGCP_MSG_PRESENCE_CALL_ID |
 	     MGCP_MSG_PRESENCE_CONN_ID | MGCP_MSG_PRESENCE_CONN_MODE);
-	mgcp_msg.codecs_len = 3;
+	mgcp_msg.ptmap_len = 3;
 	msg = mgcp_msg_gen(mgcp, &mgcp_msg);
-	mgcp_msg.codecs_len = 1;
+	mgcp_msg.ptmap_len = 1;
 	printf("%s\n", (char *)msg->data);
 
 	printf("Generated MDCX message:\n");
@@ -209,9 +205,9 @@ void test_mgcp_msg(void)
 	    (MGCP_MSG_PRESENCE_ENDPOINT | MGCP_MSG_PRESENCE_CALL_ID |
 	     MGCP_MSG_PRESENCE_CONN_ID | MGCP_MSG_PRESENCE_CONN_MODE |
 	     MGCP_MSG_PRESENCE_AUDIO_IP | MGCP_MSG_PRESENCE_AUDIO_PORT);
-	mgcp_msg.codecs_len = 2;
+	mgcp_msg.ptmap_len = 2;
 	msg = mgcp_msg_gen(mgcp, &mgcp_msg);
-	mgcp_msg.codecs_len = 1;
+	mgcp_msg.ptmap_len = 1;
 	printf("%s\n", (char *)msg->data);
 
 	printf("Generated MDCX message (three codecs, one with custom pt):\n");
@@ -220,9 +216,9 @@ void test_mgcp_msg(void)
 	    (MGCP_MSG_PRESENCE_ENDPOINT | MGCP_MSG_PRESENCE_CALL_ID |
 	     MGCP_MSG_PRESENCE_CONN_ID | MGCP_MSG_PRESENCE_CONN_MODE |
 	     MGCP_MSG_PRESENCE_AUDIO_IP | MGCP_MSG_PRESENCE_AUDIO_PORT);
-	mgcp_msg.codecs_len = 3;
+	mgcp_msg.ptmap_len = 3;
 	msg = mgcp_msg_gen(mgcp, &mgcp_msg);
-	mgcp_msg.codecs_len = 1;
+	mgcp_msg.ptmap_len = 1;
 	printf("%s\n", (char *)msg->data);
 
 	printf("Generated DLCX message:\n");
@@ -330,8 +326,10 @@ void test_mgcp_client_cancel(void)
 		.presence = (MGCP_MSG_PRESENCE_ENDPOINT | MGCP_MSG_PRESENCE_CALL_ID
 			     | MGCP_MSG_PRESENCE_CONN_ID | MGCP_MSG_PRESENCE_CONN_MODE),
 		.ptime = 20,
-		.codecs[0] = CODEC_AMR_8000_1,
-		.codecs_len = 1
+		.ptmap = {
+			{ .codec = CODEC_AMR_8000_1, .pt = CODEC_AMR_8000_1 },
+		},
+		.ptmap_len = 1
 	};
 
 	printf("\n%s():\n", __func__);
@@ -339,7 +337,7 @@ void test_mgcp_client_cancel(void)
 
 	if (mgcp)
 		talloc_free(mgcp);
-	mgcp = mgcp_client_init(ctx, &conf);
+	mgcp = mgcp_client_init(ctx, conf);
 
 	msg = mgcp_msg_gen(mgcp, &mgcp_msg);
 	trans_id = mgcp_msg_trans_id(msg);
@@ -531,7 +529,7 @@ void test_sdp_section_start(void)
 	OSMO_ASSERT(!failures);
 }
 
-static void test_map_pt_to_codec(void)
+static void test_map_str_to_codec(void)
 {
 	/* Full form */
 	OSMO_ASSERT(map_str_to_codec("PCMU/8000/1") == CODEC_PCMU_8000_1);
@@ -630,7 +628,7 @@ void test_mgcp_client_e1_epname(void)
 
 	if (mgcp)
 		talloc_free(mgcp);
-	mgcp = mgcp_client_init(ctx, &conf);
+	mgcp = mgcp_client_init(ctx, conf);
 
 	/* Valid endpoint names */
 	epname = (char *)mgcp_client_e1_epname(ctx, mgcp, 1, 15, 64, 0);
@@ -675,6 +673,214 @@ void test_mgcp_client_e1_epname(void)
 	OSMO_ASSERT(epname == NULL);
 }
 
+struct parse_response_test {
+	const char *body;
+	int expect_rc;
+	struct mgcp_response expect_params;
+};
+
+static struct parse_response_test parse_response_tests[] = {
+	{
+		.body = "200 2 OK\r\n"
+			"I: foo\r\n"
+			"\r\n"
+			"v=0\r\n"
+			"o=- name 23 IN IP4 0.0.0.0\r\n"
+			"s=-\r\n"
+			"c=IN IP4 1.2.3.4\r\n"
+			"t=0 0\r\n"
+			"m=audio 23 RTP/AVP 112 3\r\n" /* <-- implicit: 3 = GSM-FR */
+			"a=rtpmap:112 AMR/8000\r\n"
+			"a=ptime:20\r\n",
+		.expect_rc = 0,
+		.expect_params = {
+			.audio_port = 23,
+			.audio_ip = "1.2.3.4",
+			.ptmap = {
+				{ .codec = CODEC_AMR_8000_1, .pt = 112 },
+				{ .codec = CODEC_GSM_8000_1, .pt = 3 },
+			},
+			.ptmap_len = 2,
+		},
+	},
+	{
+		.body = "200 2 OK\r\n"
+			"I: foo\r\n"
+			"\r\n"
+			"v=0\r\n"
+			"o=- name 23 IN IP4 0.0.0.0\r\n"
+			"s=-\r\n"
+			"c=IN IP4 1.2.3.4\r\n"
+			"t=0 0\r\n"
+			"m=audio 23 RTP/AVP 112 3\r\n"
+			"a=rtpmap:112 AMR/8000\r\n"
+			"a=rtpmap:3 GSM/8000\r\n" /* 3 == GSM-FR implicitly, is an explicit entry a problem? */
+			"a=ptime:20\r\n",
+		.expect_rc = 0,
+		.expect_params = {
+			.audio_port = 23,
+			.audio_ip = "1.2.3.4",
+			.ptmap = {
+				{ .codec = CODEC_AMR_8000_1, .pt = 112 },
+				{ .codec = CODEC_GSM_8000_1, .pt = 3 }, /* no, not a problem */
+			},
+			.ptmap_len = 2,
+		},
+	},
+	{
+		.body = "200 2 OK\r\n"
+			"I: foo\r\n"
+			"\r\n"
+			"v=0\r\n"
+			"o=- name 23 IN IP4 0.0.0.0\r\n"
+			"s=-\r\n"
+			"c=IN IP4 1.2.3.4\r\n"
+			"t=0 0\r\n"
+			"m=audio 23 RTP/AVP 3\r\n" /* <-- 112 is missing here. Will it still appear? */
+			"a=rtpmap:112 AMR/8000\r\n"
+			"a=ptime:20\r\n",
+		.expect_rc = 0,
+		.expect_params = {
+			.audio_port = 23,
+			.audio_ip = "1.2.3.4",
+			.ptmap = {
+				{ .codec = CODEC_GSM_8000_1, .pt = 3 },
+				{ .codec = CODEC_AMR_8000_1, .pt = 112 }, /* <-- yes, it was added to the end. */
+			},
+			.ptmap_len = 2,
+		},
+	},
+	{
+		/* test MGCP_MAX_CODECS */
+		.body = "200 2 OK\r\n"
+			"I: foo\r\n"
+			"\r\n"
+			"v=0\r\n"
+			"o=- name 23 IN IP4 0.0.0.0\r\n"
+			"s=-\r\n"
+			"c=IN IP4 1.2.3.4\r\n"
+			"t=0 0\r\n"
+			"m=audio 23 RTP/AVP 101 102 103 104 105 106 107 108 109 110\r\n" /* <-- 10 codecs max */
+			"a=rtpmap:101 AMR/8000\r\n"
+			"a=rtpmap:102 AMR/8000\r\n"
+			"a=rtpmap:103 AMR/8000\r\n"
+			"a=rtpmap:104 AMR/8000\r\n"
+			"a=rtpmap:105 AMR/8000\r\n"
+			"a=rtpmap:106 AMR/8000\r\n"
+			"a=rtpmap:107 AMR/8000\r\n"
+			"a=rtpmap:108 AMR/8000\r\n"
+			"a=rtpmap:109 AMR/8000\r\n"
+			"a=rtpmap:110 AMR/8000\r\n"
+			"a=ptime:20\r\n",
+		.expect_rc = 0,
+		.expect_params = {
+			.audio_port = 23,
+			.audio_ip = "1.2.3.4",
+			.ptmap = {
+				{ .codec = CODEC_AMR_8000_1, .pt = 101 },
+				{ .codec = CODEC_AMR_8000_1, .pt = 102 },
+				{ .codec = CODEC_AMR_8000_1, .pt = 103 },
+				{ .codec = CODEC_AMR_8000_1, .pt = 104 },
+				{ .codec = CODEC_AMR_8000_1, .pt = 105 },
+				{ .codec = CODEC_AMR_8000_1, .pt = 106 },
+				{ .codec = CODEC_AMR_8000_1, .pt = 107 },
+				{ .codec = CODEC_AMR_8000_1, .pt = 108 },
+				{ .codec = CODEC_AMR_8000_1, .pt = 109 },
+				{ .codec = CODEC_AMR_8000_1, .pt = 110 },
+			},
+			.ptmap_len = 10,
+		},
+	},
+	{
+		/* test MGCP_MAX_CODECS */
+		.body = "200 2 OK\r\n"
+			"I: foo\r\n"
+			"\r\n"
+			"v=0\r\n"
+			"o=- name 23 IN IP4 0.0.0.0\r\n"
+			"s=-\r\n"
+			"c=IN IP4 1.2.3.4\r\n"
+			"t=0 0\r\n"
+			"m=audio 23 RTP/AVP 101 102 103 104 105 106 107 108 109 110 3\r\n" /* <-- 11 > MGCP_MAX_CODECS */
+			"a=rtpmap:101 AMR/8000\r\n"
+			"a=rtpmap:102 AMR/8000\r\n"
+			"a=rtpmap:103 AMR/8000\r\n"
+			"a=rtpmap:104 AMR/8000\r\n"
+			"a=rtpmap:105 AMR/8000\r\n"
+			"a=rtpmap:106 AMR/8000\r\n"
+			"a=rtpmap:107 AMR/8000\r\n"
+			"a=rtpmap:108 AMR/8000\r\n"
+			"a=rtpmap:109 AMR/8000\r\n"
+			"a=rtpmap:110 AMR/8000\r\n"
+			"a=ptime:20\r\n",
+		.expect_rc = -EINVAL,
+	},
+};
+
+static void test_parse_response(void)
+{
+	int i;
+	int failures = 0;
+
+	for (i = 0; i < ARRAY_SIZE(parse_response_tests); i++) {
+		int rc;
+		struct parse_response_test *t = &parse_response_tests[i];
+		struct mgcp_response *r = talloc_zero(ctx, struct mgcp_response);
+		int p;
+
+		r->body = talloc_strdup(r, t->body);
+
+		//printf("\n%s() test [%d]:\n", __func__, i);
+		fprintf(stderr, "\n%s() test [%d]:\n", __func__, i);
+		fprintf(stderr, "body: \"%s\"\n", osmo_escape_str(r->body, -1));
+
+		rc = mgcp_response_parse_params(r);
+
+		fprintf(stderr, "got rc=%d\n", rc);
+		if (rc != t->expect_rc) {
+			fprintf(stderr, "FAIL: Expected rc=%d\n", t->expect_rc);
+			failures++;
+		}
+		if (rc) {
+			talloc_free(r);
+			continue;
+		}
+
+		fprintf(stderr, "got audio_ip=\"%s\"\n", r->audio_ip);
+		if (strcmp(r->audio_ip, t->expect_params.audio_ip)) {
+			fprintf(stderr, "FAIL: Expected audio_ip=\"%s\"\n", t->expect_params.audio_ip);
+			failures++;
+		}
+		fprintf(stderr, "got audio_port=%u\n", r->audio_port);
+		if (r->audio_port != t->expect_params.audio_port) {
+			fprintf(stderr, "FAIL: Expected audio_port=%u\n", t->expect_params.audio_port);
+			failures++;
+		}
+
+		for (p = 0; p < r->ptmap_len; p++) {
+			struct ptmap *got = &r->ptmap[p];
+			struct ptmap *expect = NULL;
+			fprintf(stderr, "  %d %s\n", got->pt, osmo_mgcpc_codec_name(got->codec));
+			if (p >= t->expect_params.ptmap_len) {
+				fprintf(stderr, "    - ERROR: too many codec entries\n");
+				failures++;
+				continue;
+			}
+			expect = &t->expect_params.ptmap[p];
+			if (ptmap_cmp(got, expect)) {
+				fprintf(stderr, "    - ERROR: expected: %d %s\n",
+					expect->pt, osmo_mgcpc_codec_name(expect->codec));
+				failures++;
+			}
+		}
+
+		talloc_free(r);
+	}
+
+	OSMO_ASSERT(!failures);
+}
+
+
 static const struct log_info_cat log_categories[] = {
 };
 
@@ -697,15 +903,17 @@ int main(int argc, char **argv)
 
 	log_set_category_filter(osmo_stderr_target, DLMGCP, 1, LOGL_DEBUG);
 
-	mgcp_client_conf_init(&conf);
+	conf = mgcp_client_conf_alloc(ctx);
 
 	test_mgcp_msg();
 	test_mgcp_client_cancel();
 	test_sdp_section_start();
 	test_map_codec_to_pt_and_map_pt_to_codec();
-	test_map_pt_to_codec();
+	test_map_str_to_codec();
 	test_mgcp_client_e1_epname();
 
+	test_parse_response();
+
 	printf("Done\n");
 	fprintf(stderr, "Done\n");
 	return EXIT_SUCCESS;

tests/mgcp_client/mgcp_client_test.err

@@ -1,5 +1,6 @@
 DLMGCP MGW(mgw) MGCP client: using endpoint domain '@mgw'
-DLMGCP MGW(mgw) Message buffer to small, can not generate MGCP message (SDP)
+DLMGCP MGW(mgw) Message buffer too small, can not generate MGCP message (SDP)
+DLMGCP MGW(mgw) Failed to add SDP, can not generate MGCP message
 
 test_mgcp_client_cancel():
 DLMGCP MGW(mgw) MGCP client: using endpoint domain '@mgw'
@@ -10,6 +11,7 @@ DLMGCP MGW(mgw) Cannot cancel, no such transaction: 1
 - cancel succeeds
 DLMGCP MGW(mgw) Canceled transaction 1
 - late response gets discarded
+DLMGCP MGW(mgw) MGCP link to MGW now considered UP
 DLMGCP MGW(mgw) MGCP client: Rx 200 1 OK
 DLMGCP MGW(mgw) Cannot find matching MGCP transaction for trans_id 1
 - canceling again does nothing
@@ -135,4 +137,51 @@ DLMGCP MGW(mgw) Cannot compose MGCP e1-endpoint name (ds/e1-15/s-1/su128-0@mgw),
 DLMGCP MGW(mgw) Cannot compose MGCP e1-endpoint name (ds/e1-15/s-1/su8-16@mgw), rate(8)/offset(16) combination is invalid!
 DLMGCP MGW(mgw) Cannot compose MGCP e1-endpoint name (ds/e1-15/s-0/su8-2@mgw), E1-timeslot number (0) is invalid!
 DLMGCP MGW(mgw) Cannot compose MGCP e1-endpoint name (ds/e1-15/s-64/su8-2@mgw), E1-timeslot number (64) is invalid!
+
+test_parse_response() test [0]:
+body: "200 2 OK\r\nI: foo\r\n\r\nv=0\r\no=- name 23 IN IP4 0.0.0.0\r\ns=-\r\nc=IN IP4 1.2.3.4\r\nt=0 0\r\nm=audio 23 RTP/AVP 112 3\r\na=rtpmap:112 AMR/8000\r\na=ptime:20\r\n"
+got rc=0
+got audio_ip="1.2.3.4"
+got audio_port=23
+  112 AMR/8000/1
+  3 GSM/8000/1
+
+test_parse_response() test [1]:
+body: "200 2 OK\r\nI: foo\r\n\r\nv=0\r\no=- name 23 IN IP4 0.0.0.0\r\ns=-\r\nc=IN IP4 1.2.3.4\r\nt=0 0\r\nm=audio 23 RTP/AVP 112 3\r\na=rtpmap:112 AMR/8000\r\na=rtpmap:3 GSM/8000\r\na=ptime:20\r\n"
+got rc=0
+got audio_ip="1.2.3.4"
+got audio_port=23
+  112 AMR/8000/1
+  3 GSM/8000/1
+
+test_parse_response() test [2]:
+body: "200 2 OK\r\nI: foo\r\n\r\nv=0\r\no=- name 23 IN IP4 0.0.0.0\r\ns=-\r\nc=IN IP4 1.2.3.4\r\nt=0 0\r\nm=audio 23 RTP/AVP 3\r\na=rtpmap:112 AMR/8000\r\na=ptime:20\r\n"
+DLMGCP error in MGCP message: 'a=rtpmap:112' has no matching entry in 'm=audio ... 112'
+got rc=0
+got audio_ip="1.2.3.4"
+got audio_port=23
+  3 GSM/8000/1
+  112 AMR/8000/1
+
+test_parse_response() test [3]:
+body: "200 2 OK\r\nI: foo\r\n\r\nv=0\r\no=- name 23 IN IP4 0.0.0.0\r\ns=-\r\nc=IN IP4 1.2.3.4\r\nt=0 0\r\nm=audio 23 RTP/AVP 101 102 103 104 105 106 107 108 109 110\r\na=rtpmap:101 AMR/8000\r\na=rtpmap:102 AMR/8000\r\na=rtpmap:103 AMR/8000\r\na=rtpmap:104 AMR/8"
+got rc=0
+got audio_ip="1.2.3.4"
+got audio_port=23
+  101 AMR/8000/1
+  102 AMR/8000/1
+  103 AMR/8000/1
+  104 AMR/8000/1
+  105 AMR/8000/1
+  106 AMR/8000/1
+  107 AMR/8000/1
+  108 AMR/8000/1
+  109 AMR/8000/1
+  110 AMR/8000/1
+
+test_parse_response() test [4]:
+body: "200 2 OK\r\nI: foo\r\n\r\nv=0\r\no=- name 23 IN IP4 0.0.0.0\r\ns=-\r\nc=IN IP4 1.2.3.4\r\nt=0 0\r\nm=audio 23 RTP/AVP 101 102 103 104 105 106 107 108 109 110 3\r\na=rtpmap:101 AMR/8000\r\na=rtpmap:102 AMR/8000\r\na=rtpmap:103 AMR/8000\r\na=rtpmap:104 AMR"
+DLMGCP SDP: can parse only up to 10 payload type numbers
+DLMGCP Failed to parse SDP parameter payload types (RTP/AVP)
+got rc=-22
 Done

tests/sdp/Makefile.am

@@ -0,0 +1,38 @@
+AM_CPPFLAGS = \
+	$(all_includes) \
+	-I$(top_srcdir)/include \
+	-I$(top_builddir)/include \
+	-I$(top_srcdir) \
+	$(NULL)
+
+AM_CFLAGS = \
+	-Wall \
+	-ggdb3 \
+	$(LIBOSMOCORE_CFLAGS) \
+	$(COVERAGE_CFLAGS) \
+	$(NULL)
+
+AM_LDFLAGS = \
+	$(COVERAGE_LDFLAGS) \
+	-no-install \
+	$(NULL)
+
+EXTRA_DIST = \
+	sdp_fmtp_test.ok \
+	sdp_fmtp_test.err \
+	$(NULL)
+
+check_PROGRAMS = \
+	sdp_fmtp_test \
+	$(NULL)
+
+sdp_fmtp_test_SOURCES = \
+	sdp_fmtp_test.c \
+	$(NULL)
+
+sdp_fmtp_test_LDADD = \
+	$(top_builddir)/src/libosmo-sdp/libosmo-sdp.la \
+	$(NULL)
+
+update_exp:
+	$(builddir)/sdp_fmtp_test >$(srcdir)/sdp_fmtp_test.ok 2>$(srcdir)/sdp_fmtp_test.err

tests/sdp/sdp_fmtp_test.c

@@ -0,0 +1,126 @@
+#include <inttypes.h>
+#include <osmocom/core/utils.h>
+#include <osmocom/core/application.h>
+#include <osmocom/core/logging.h>
+
+#include <osmocom/sdp/fmtp.h>
+
+struct get_val_test {
+	const char *fmtp_string;
+	const char *val_name;
+	bool expect_rc;
+	const char *expect_val;
+};
+
+const struct get_val_test get_val_tests[] = {
+	{
+		"foo=123;bar=success;baz=456", "foo",
+		true, "123"
+	},
+	{
+		"foo=123;bar=success;baz=456", "bar",
+		true, "success"
+	},
+	{
+		"foo=123;bar=success;baz=456", "baz",
+		true, "456"
+	},
+};
+
+void test_get_val(void)
+{
+	int i;
+	printf("\n--- %s()\n", __func__);
+
+	for (i = 0; i < ARRAY_SIZE(get_val_tests); i++) {
+		const struct get_val_test *t = &get_val_tests[i];
+		char val[128] = {};
+		bool rc = osmo_sdp_fmtp_get_val(val, sizeof(val), t->fmtp_string, t->val_name);
+		bool ok;
+		printf("osmo_sdp_fmtp_get_val('%s', '%s') rc=%s",
+		       t->fmtp_string, t->val_name,
+		       rc ? "true" : "false");
+		if (rc)
+			printf(" val='%s'", val);
+		ok = true;
+		if (rc != t->expect_rc) {
+			printf(" ERROR: expected rc=%s", t->expect_rc ? "true" : "false");
+			ok = false;
+		}
+		if (t->expect_val && strcmp(val, t->expect_val)) {
+			printf(" ERROR: expected val='%s'", t->expect_val);
+			ok = false;
+		}
+		if (ok)
+			printf(" ok");
+		printf("\n");
+	}
+	printf("\n--- %s() DONE\n", __func__);
+}
+
+struct get_int_test {
+	const char *fmtp_string;
+	const char *val_name;
+	int64_t defval;
+	int64_t expect_rc;
+};
+
+const struct get_int_test get_int_tests[] = {
+	{
+		"foo=123;bar=success;baz=456", "foo", -1,
+		123
+	},
+	{
+		"foo=123;bar=success;baz=456", "bar", -1,
+		-1
+	},
+	{
+		"foo=123;bar=success;baz=456", "baz", -1,
+		456
+	},
+};
+
+void test_get_int(void)
+{
+	int i;
+	printf("\n--- %s()\n", __func__);
+
+	for (i = 0; i < ARRAY_SIZE(get_int_tests); i++) {
+		const struct get_int_test *t = &get_int_tests[i];
+		int64_t rc = osmo_sdp_fmtp_get_int(t->fmtp_string, t->val_name, t->defval);
+		printf("osmo_sdp_fmtp_get_int('%s', '%s') rc=%"PRId64,
+		       t->fmtp_string, t->val_name, rc);
+		if (rc != t->expect_rc) {
+			printf(" ERROR: expected rc=%"PRId64, t->expect_rc);
+		}
+		else {
+			printf(" ok");
+		}
+		printf("\n");
+	}
+	printf("\n--- %s() DONE\n", __func__);
+}
+
+static const struct log_info_cat log_categories[] = {
+};
+
+const struct log_info log_info = {
+        .cat = log_categories,
+        .num_cat = ARRAY_SIZE(log_categories),
+};
+
+int main(void)
+{
+	void *ctx = talloc_named_const(NULL, 1, "sdp_fmtp_test");
+
+	osmo_init_logging2(ctx, &log_info);
+	log_set_print_filename2(osmo_stderr_target, LOG_FILENAME_NONE);
+	log_set_print_timestamp(osmo_stderr_target, 0);
+	log_set_use_color(osmo_stderr_target, 0);
+	log_set_print_category_hex(osmo_stderr_target, 0);
+	log_set_print_category(osmo_stderr_target, 1);
+
+	test_get_val();
+	test_get_int();
+	return 0;
+}

tests/sdp/sdp_fmtp_test.ok

@@ -0,0 +1,14 @@
+
+--- test_get_val()
+osmo_sdp_fmtp_get_val('foo=123;bar=success;baz=456', 'foo') rc=true val='123' ok
+osmo_sdp_fmtp_get_val('foo=123;bar=success;baz=456', 'bar') rc=true val='success' ok
+osmo_sdp_fmtp_get_val('foo=123;bar=success;baz=456', 'baz') rc=true val='456' ok
+
+--- test_get_val() DONE
+
+--- test_get_int()
+osmo_sdp_fmtp_get_int('foo=123;bar=success;baz=456', 'foo') rc=123 ok
+osmo_sdp_fmtp_get_int('foo=123;bar=success;baz=456', 'bar') rc=-1 ok
+osmo_sdp_fmtp_get_int('foo=123;bar=success;baz=456', 'baz') rc=456 ok
+
+--- test_get_int() DONE

tests/testsuite.at

@@ -13,3 +13,10 @@ AT_KEYWORDS([mgcp])
 cat $abs_srcdir/mgcp/mgcp_test.ok > expout
 AT_CHECK([$abs_top_builddir/tests/mgcp/mgcp_test], [], [expout], [ignore])
 AT_CLEANUP
+
+AT_SETUP([sdp_fmtp])
+AT_KEYWORDS([sdp_fmtp])
+cat $abs_srcdir/sdp/sdp_fmtp_test.ok > expout
+cat $abs_srcdir/sdp/sdp_fmtp_test.err > experr
+AT_CHECK([$abs_top_builddir/tests/sdp/sdp_fmtp_test], [], [expout], [experr])
+AT_CLEANUP