WIP

Change-Id: Ia8d595095462c30a56b8a0b30c8d24632776e4cc

Makefile.am

@@ -1,5 +1,14 @@
 ## Process this file with automake to produce Makefile.in
-SUBDIRS = lib gtp ggsn sgsnemu doc contrib utils tests
+SUBDIRS = \
+	  lib \
+	  gtp \
+	  ggsn \
+	  sgsnemu \
+	  doc \
+	  contrib \
+	  utils \
+	  tests \
+	  $(NULL)
 
 pkgconfigdir = $(libdir)/pkgconfig
 pkgconfig_DATA = libgtp.pc

README.md

@@ -27,9 +27,10 @@ There is a web interface at <https://gitea.osmocom.org/cellular-infrastructure/o
 Documentation
 -------------
 
-There currently is no other documentation other than the wiki on the
-homepage.  It would be great if somebody would work towards a user
-manual that can become part of the osmo-gsm-manuals project.
+The user manual and VTY reference are optionally built in PDF form
+as part of the build process. Find pre-rendered versions here:
+
+https://ftp.osmocom.org/docs/osmo-ggsn/master/
 
 Mailing List
 ------------

TODO-RELEASE

@@ -7,3 +7,5 @@
 # If any interfaces have been added since the last public release: c:r:a + 1.
 # If any interfaces have been removed or changed since the last public release: c:r:0.
 #library	what		description / commit summary line
+libgtp		REMOVE		remove GTP cause defines of reserved values
+libgtpnl > 1.2.5		gtp_tunnel_set_family()

configure.ac

@@ -154,9 +154,10 @@ adl_FUNC_GETOPT_LONG
 
 AM_INIT_AUTOMAKE([foreign])
 
-PKG_CHECK_MODULES(LIBOSMOCORE, libosmocore >= 1.8.0)
-PKG_CHECK_MODULES(LIBOSMOVTY, libosmovty >= 1.8.0)
-PKG_CHECK_MODULES(LIBOSMOCTRL, libosmoctrl >= 1.8.0)
+PKG_CHECK_MODULES(LIBOSMOCORE, libosmocore >= 1.9.0)
+PKG_CHECK_MODULES(LIBOSMOGSM, libosmogsm >= 1.9.0)
+PKG_CHECK_MODULES(LIBOSMOVTY, libosmovty >= 1.9.0)
+PKG_CHECK_MODULES(LIBOSMOCTRL, libosmoctrl >= 1.9.0)
 
 AC_ARG_ENABLE(sanitize,
 	[AS_HELP_STRING(

contrib/osmo-ggsn.spec.in

@@ -30,9 +30,9 @@ BuildRequires:  pkgconfig >= 0.20
 BuildRequires:  systemd-rpm-macros
 %endif
 BuildRequires:  pkgconfig(libgtpnl) >= 1.2.0
-BuildRequires:  pkgconfig(libosmocore) >= 1.8.0
-BuildRequires:  pkgconfig(libosmoctrl) >= 1.8.0
-BuildRequires:  pkgconfig(libosmovty) >= 1.8.0
+BuildRequires:  pkgconfig(libosmocore) >= 1.9.0
+BuildRequires:  pkgconfig(libosmoctrl) >= 1.9.0
+BuildRequires:  pkgconfig(libosmovty) >= 1.9.0
 Obsoletes:      openggsn
 %{?systemd_requires}
 

contrib/systemd/osmo-ggsn.service

@@ -1,6 +1,7 @@
 [Unit]
 Description=OsmoGGSN
-After=networking.service
+After=network-online.target
+Wants=network-online.target
 
 [Service]
 Type=simple

debian/changelog

@@ -1,3 +1,38 @@
+osmo-ggsn (1.11.0) unstable; urgency=medium
+
+  [ Daniel Willmann ]
+  * gtp: Add net GTP cause values and a function to check for success
+
+ -- Oliver Smith <osmith@sysmocom.de>  Tue, 28 Nov 2023 13:38:29 +0100
+
+osmo-ggsn (1.10.2) unstable; urgency=medium
+
+  [ Vadim Yanitskiy ]
+  * Do not hard-code -g and -O2 in CFLAGS
+  * tests: use -no-install libtool flag to avoid ./lt-* scripts
+
+  [ Oliver Smith ]
+  * doc/manuals/chapters/configuration: fix typo
+  * debian: set compat level to 10
+  * systemd: depend on networking-online.target
+  * README: update documentation section
+  * doc: running: update kernel-gtp limitations
+  * lib/in46_addr: add in46a_from_gsna
+
+ -- Pau Espin Pedrol <pespin@sysmocom.de>  Tue, 12 Sep 2023 14:36:10 +0200
+
+osmo-ggsn (1.10.1) unstable; urgency=medium
+
+  [ Oliver Smith ]
+  * debian/libgtp6.shlibs: new file
+
+  [ Vadim Yanitskiy ]
+  * lib/icmpv6.h: fix struct icmpv6_{radv_hdr,opt_prefix}
+  * gtp/gsn.c: fix 'No newline at end of file'
+  * gtp: use OSMO_ASSERT() in gtp_new()
+
+ -- Vadim Yanitskiy <vyanitskiy@sysmocom.de>  Mon, 27 Feb 2023 22:35:47 +0700
+
 osmo-ggsn (1.10.0) unstable; urgency=medium
 
   [ Max ]

debian/compat

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

debian/control

@@ -2,12 +2,12 @@ Source: osmo-ggsn
 Maintainer: Osmocom team <openbsc@lists.osmocom.org>
 Section: net
 Priority: optional
-Build-Depends: debhelper (>= 9),
+Build-Depends: debhelper (>= 10),
                autotools-dev,
                pkg-config,
                libdpkg-perl, git,
                dh-autoreconf,
-               libosmocore-dev (>= 1.8.0),
+               libosmocore-dev (>= 1.9.0),
                osmo-gsm-manuals-dev,
                libgtpnl-dev (>= 1.2.0)
 Standards-Version: 3.9.6

debian/libgtp6.shlibs

@@ -0,0 +1,2 @@
+# Most recent version of the package that added new symbols (OS#5318)
+libgtp 6 libgtp6 (>= 1.8.0)

doc/manuals/chapters/configuration.adoc

@@ -101,7 +101,7 @@ OsmoGGSN(config-ggsn)# no shutdown ggsn <4>
 ----
 <1> Change into privileged mode
 <2> Enter the interactive configuration mode
-<3> Enter the config ndoe of the GGSN instance `ggsn0`
+<3> Enter the config node of the GGSN instance `ggsn0`
 <4> Take the GGSN instance out of shutdown
 
 
@@ -121,7 +121,7 @@ OsmoGGSN(config-ggsn)# shutdown ggsn <4>
 ----
 <1> Change into privileged mode
 <2> Enter the interactive configuration mode
-<3> Enter the config ndoe of the GGSN instance `ggsn0`
+<3> Enter the config node of the GGSN instance `ggsn0`
 <4> Shut down the GGSN instance
 
 
@@ -215,8 +215,8 @@ OsmoGGSN(config-ggsn-apn)# no shutdown <5>
 ----
 <1> Change into privileged mode
 <2> Enter the interactive configuration mode
-<3> Enter the config ndoe of the GGSN instance `ggsn0`
-<4> Enter the config ndoe of the APN `internet`
+<3> Enter the config node of the GGSN instance `ggsn0`
+<4> Enter the config node of the APN `internet`
 <5> Take the APN out of shutdown
 
 
@@ -237,8 +237,8 @@ OsmoGGSN(config-ggsn-apn)# shutdown <5>
 ----
 <1> Change into privileged mode
 <2> Enter the interactive configuration mode
-<3> Enter the config ndoe of the GGSN instance `ggsn0`
-<4> Enter the config ndoe of the APN `internet`
+<3> Enter the config node of the GGSN instance `ggsn0`
+<4> Enter the config node of the APN `internet`
 <5> Shut down the APN
 
 [[ggsn_no_root]]
@@ -302,7 +302,7 @@ Name=apn0 <1>
 Address=192.168.7.1/24 <2>
 IPMasquerade=yes <3>
 ----
-<1> The netowrk device name, which must match the one in the apn0.netdev unit file above
+<1> The network device name, which must match the one in the apn0.netdev unit file above
 <2> The local IP address configured on the device
 <3> Requesting systemd to configure IP masquerading for this interface.  Depending on your needs,
     You may not want this if you have proper end-to-end routing set up, and want to have transparent

doc/manuals/chapters/running.adoc

@@ -83,7 +83,12 @@ ggsn ggsn0
 
 === GTP-U kernel module
 
-WARNING: As of writing, the kernel module does not support IPv6.
+WARNING: As of writing, IPv6 support for the kernel module has not been
+         upstreamed yet (OS#1952).
+
+WARNING: As of writing, it is not possible to configure multiple APNs with
+         gtpu-mode kernel-gpt. This is a limitation in OsmoGGSN, not in the
+         kernel module (OS#6106).
 
 OsmoGGSN has support to use the Linux kernel GTP-U tunnel driver to accelerate
 the data/user plane while still implementing the control plane (GTP-C) in

ggsn/Makefile.am

@@ -2,7 +2,15 @@ bin_PROGRAMS = osmo-ggsn
 
 AM_LDFLAGS = @EXEC_LDFLAGS@
 
-AM_CFLAGS = -O2 -D_GNU_SOURCE -fno-builtin -Wall -DSBINDIR='"$(sbindir)"' -ggdb $(LIBOSMOCORE_CFLAGS) $(LIBOSMOCTRL_CFLAGS) $(LIBOSMOVTY_CFLAGS)
+AM_CFLAGS = \
+	    -D_GNU_SOURCE \
+	    -fno-builtin \
+	    -Wall \
+	    -DSBINDIR='"$(sbindir)"' \
+	    $(LIBOSMOCORE_CFLAGS) \
+	    $(LIBOSMOCTRL_CFLAGS) \
+	    $(LIBOSMOVTY_CFLAGS) \
+	    $(NULL)
 
 osmo_ggsn_LDADD = @EXEC_LDADD@ -lgtp -L../gtp ../lib/libmisc.a $(LIBOSMOCORE_LIBS) $(LIBOSMOCTRL_LIBS) $(LIBOSMOVTY_LIBS)
 

ggsn/ggsn.c

@@ -193,7 +193,7 @@ int apn_start(struct apn_ctx *apn)
 		}
 		LOGPAPN(LOGL_INFO, apn, "Opened TUN device %s\n", apn->tun.tun->devname);
 
-		/* Register with libosmcoore */
+		/* Register with libosmocore */
 		osmo_fd_setup(&apn->tun.fd, apn->tun.tun->fd, OSMO_FD_READ, ggsn_tun_fd_cb, apn, 0);
 		osmo_fd_register(&apn->tun.fd);
 
@@ -202,11 +202,6 @@ int apn_start(struct apn_ctx *apn)
 		break;
 	case APN_GTPU_MODE_KERNEL_GTP:
 		LOGPAPN(LOGL_INFO, apn, "Opening Kernel GTP device %s\n", apn->tun.cfg.dev_name);
-		if (apn->cfg.apn_type_mask & (APN_TYPE_IPv6|APN_TYPE_IPv4v6)) {
-			LOGPAPN(LOGL_ERROR, apn, "Kernel GTP currently supports only IPv4\n");
-			apn_stop(apn);
-			return -1;
-		}
 		if (gsn == NULL) {
 			/* skip bringing up the APN now if the GSN is not initialized yet.
 			 * This happens during initial load of the config file, as the
@@ -536,10 +531,11 @@ int create_context_ind(struct pdp_t *pdp)
 
 	in46a_to_eua(addr, num_addr, &pdp->eua);
 
-	if (apn->cfg.gtpu_mode == APN_GTPU_MODE_KERNEL_GTP && apn_supports_ipv4(apn)) {
-		/* TODO: In IPv6, EUA doesn't contain the actual IP addr/prefix! */
+	if (apn->cfg.gtpu_mode == APN_GTPU_MODE_KERNEL_GTP) {
 		if (gtp_kernel_tunnel_add(pdp, apn->tun.cfg.dev_name) < 0) {
 			LOGPPDP(LOGL_ERROR, pdp, "Cannot add tunnel to kernel: %s\n", strerror(errno));
+			if (addrv6 && errno == EINVAL)
+				LOGPPDP(LOGL_ERROR, pdp, "Maybe your kernel does not support GTP-U with IPv6 yet?\n");
 			gtp_create_context_resp(gsn, pdp, GTPCAUSE_SYS_FAIL);
 			return 0;
 		}

ggsn/ggsn_vty.c

@@ -814,10 +814,7 @@ static const char *print_gsnaddr(const struct ul16_t *in)
 {
 	struct in46_addr in46;
 
-	in46.len = in->l;
-	OSMO_ASSERT(in->l <= sizeof(in46.v6));
-	memcpy(&in46.v6, in->v, in->l);
-
+	in46a_from_gsna(in, &in46);
 	return in46a_ntoa(&in46);
 }
 

ggsn/pco.c

@@ -110,6 +110,7 @@ ret_broken:
 		osmo_hexdump_nospc((const uint8_t *)pco_in, pco_in->length));
 }
 
+/* Handle IP Control Protocol, RFC 1332, extensions in RFC 1877 */
 static void process_pco_element_ipcp(const struct pco_element *pco_elem, struct msgb *resp,
 				     const struct apn_ctx *apn, struct pdp_t *pdp)
 {

ggsn/pco.h

@@ -42,12 +42,11 @@ struct pco_element {
 	uint8_t data[0];
 } __attribute__((packed));
 
-
-/* RFC 1332 */
+/* RFC 1332 IP Control Protocol options, extensions in RFC 1877 */
 enum ipcp_options {
-	IPCP_OPT_IPADDR = 3,
-	IPCP_OPT_PRIMARY_DNS = 129,
-	IPCP_OPT_SECONDARY_DNS = 131,
+	IPCP_OPT_IPADDR = 3, /* RFC 1332 3.3 */
+	IPCP_OPT_PRIMARY_DNS = 129, /* RFC 1877 1.1 */
+	IPCP_OPT_SECONDARY_DNS = 131,  /* RFC 1877 1.2 */
 };
 
 struct ipcp_option_hdr {

gtp/Makefile.am

@@ -2,14 +2,34 @@
 # Please read chapter "Library interface versions" of the libtool documentation
 # before making any modifications: https://www.gnu.org/software/libtool/manual/html_node/Versioning.html
 # If major=current-age is increased, remember to update the dh_strip line in debian/rules!
-LIBVERSION=9:0:3
+LIBVERSION=9:1:3
 
 lib_LTLIBRARIES = libgtp.la
 
 include_HEADERS = gtp.h gsn.h pdp.h gtpie.h
 
-AM_CFLAGS = -O2 -fno-builtin -Wall -DSBINDIR='"$(sbindir)"' -ggdb $(LIBOSMOCORE_CFLAGS)
+AM_CFLAGS = \
+	    -fno-builtin \
+	    -Wall \
+	    -DSBINDIR='"$(sbindir)"' \
+	    $(LIBOSMOCORE_CFLAGS) \
+		$(LIBOSMOGSM_CFLAGS) \
+	    $(NULL)
+
+libgtp_la_SOURCES = \
+		    gsn.c \
+		    gsn.h \
+		    gtp.c \
+		    gtp.h \
+		    gtpie.c \
+		    gtpie.h \
+		    lookupa.c \
+		    lookupa.h \
+		    pdp.c \
+		    pdp.h \
+		    queue.c \
+		    queue.h \
+		    $(NULL)
 
-libgtp_la_SOURCES = gtp.c gtp.h gsn.c gsn.h gtpie.c gtpie.h pdp.c pdp.h lookupa.c lookupa.h queue.c queue.h
 libgtp_la_LDFLAGS = -version-info $(LIBVERSION) -no-undefined
-libgtp_la_LIBADD = $(LIBOSMOCORE_LIBS)
+libgtp_la_LIBADD = $(LIBOSMOCORE_LIBS) $(LIBOSMOGSM_LIBS)

gtp/gsn.c

@@ -67,7 +67,7 @@
 #define LOGP_WITH_ADDR(ss, level, addr, fmt, args...)                    \
 		LOGP(ss, level, "addr(%s:%d) " fmt,                      \
 		     inet_ntoa((addr).sin_addr), htons((addr).sin_port), \
-		     ##args);
+		     ##args)
 
 static const struct rate_ctr_desc gsn_ctr_description[] = {
 	[GSN_CTR_ERR_SOCKET] = { "err:socket", "Socket error" },
@@ -244,6 +244,12 @@ int gtp_set_cb_data_ind(struct gsn_t *gsn,
 	gsn->cb_data_ind = cb_data_ind;
 	return 0;
 }
+int gtp_set_cb_sgsn_context_request_ind(struct gsn_t *gsn,
+			     int (*cb) (struct gsn_t *gsn, struct sockaddr_in *peer, uint16_t seq, const struct osmo_routing_area_id *rai, uint32_t teic, struct osmo_mobile_identity *mi, union gtpie_member **ie))
+{
+	gsn->cb_sgsn_context_request_ind = cb;
+	return 0;
+}
 
 static int queue_timer_retrans(struct gsn_t *gsn)
 {
@@ -423,11 +429,45 @@ free_filename:
 	talloc_free(filename);
 }
 
+static int create_and_bind_socket(const char *name, struct gsn_t *gsn, int *fd, int domain,
+				  const struct in_addr *listen, int port)
+{
+	struct sockaddr_in addr;
+	int type = SOCK_DGRAM;
+	int protocol = 0;
+
+	*fd = socket(domain, type, protocol);
+
+	if (*fd < 0) {
+		rate_ctr_inc2(gsn->ctrg, GSN_CTR_ERR_SOCKET);
+		LOGP(DLGTP, LOGL_ERROR,
+		     "%s socket(domain=%d, type=%d, protocol=%d) failed: Error = %s\n",
+		     name, domain, type, protocol, strerror(errno));
+		return -errno;
+	}
+
+	memset(&addr, 0, sizeof(addr));
+	addr.sin_family = domain;
+	addr.sin_addr = *listen;
+	addr.sin_port = htons(port);
+#if defined(__FreeBSD__) || defined(__APPLE__)
+	addr.sin_len = sizeof(addr);
+#endif
+
+	if (bind(*fd, (struct sockaddr *)&addr, sizeof(addr)) < 0) {
+		rate_ctr_inc2(gsn->ctrg, GSN_CTR_ERR_SOCKET);
+		LOGP_WITH_ADDR(DLGTP, LOGL_ERROR, addr,
+			       "%s bind(fd=%d) failed: Error = %s\n",
+			       name, *fd, strerror(errno));
+		return -errno;
+	}
+
+	return 0;
+}
+
 int gtp_new(struct gsn_t **gsn, char *statedir, struct in_addr *listen,
 	    int mode)
 {
-	struct sockaddr_in addr;
-
 	LOGP(DLGTP, LOGL_NOTICE, "GTP: gtp_newgsn() started at %s\n", inet_ntoa(*listen));
 
 	*gsn = calloc(sizeof(struct gsn_t), 1);	/* TODO */
@@ -441,7 +481,7 @@ int gtp_new(struct gsn_t **gsn, char *statedir, struct in_addr *listen,
 	/* Initialize timers: */
 	(*gsn)->tdef = gtp_T_defs;
 	/* Small hack to properly reset tdef for old clients not using the tdef_group: */
-	osmo_static_assert(gtp_T_defs[0].default_val != 0, first_default_val_not_zero);
+	OSMO_ASSERT(gtp_T_defs[0].default_val != 0);
 	if (gtp_T_defs[0].val == 0)
 		osmo_tdefs_reset((*gsn)->tdef);
 
@@ -467,89 +507,35 @@ int gtp_new(struct gsn_t **gsn, char *statedir, struct in_addr *listen,
 	(*gsn)->cb_data_ind = 0;
 
 	/* Store function parameters */
+	/* Same IP for user traffic and signalling */
 	(*gsn)->gsnc = *listen;
 	(*gsn)->gsnu = *listen;
 	(*gsn)->mode = mode;
 
+	(*gsn)->fd0 = -1;
+	(*gsn)->fd1c = -1;
+	(*gsn)->fd1u = -1;
+
 	/* Create GTP version 0 socket */
-	if (((*gsn)->fd0 = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
-		rate_ctr_inc2((*gsn)->ctrg, GSN_CTR_ERR_SOCKET);
-		LOGP(DLGTP, LOGL_ERROR,
-		     "GTPv0 socket(domain=%d, type=%d, protocol=%d) failed: Error = %s\n",
-			AF_INET, SOCK_DGRAM, 0, strerror(errno));
-		return -errno;
-	}
-
-	memset(&addr, 0, sizeof(addr));
-	addr.sin_family = AF_INET;
-	addr.sin_addr = *listen;	/* Same IP for user traffic and signalling */
-	addr.sin_port = htons(GTP0_PORT);
-#if defined(__FreeBSD__) || defined(__APPLE__)
-	addr.sin_len = sizeof(addr);
-#endif
-
-	if (bind((*gsn)->fd0, (struct sockaddr *)&addr, sizeof(addr)) < 0) {
-		rate_ctr_inc2((*gsn)->ctrg, GSN_CTR_ERR_SOCKET);
-		LOGP_WITH_ADDR(DLGTP, LOGL_ERROR, addr,
-			       "bind(fd0=%d) failed: Error = %s\n",
-			       (*gsn)->fd0, strerror(errno));
-		return -errno;
-	}
+	if (create_and_bind_socket("GTPv0", *gsn, &(*gsn)->fd0, AF_INET, listen, GTP0_PORT) < 0)
+		goto error;
 
 	/* Create GTP version 1 control plane socket */
-	if (((*gsn)->fd1c = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
-		rate_ctr_inc2((*gsn)->ctrg, GSN_CTR_ERR_SOCKET);
-		LOGP(DLGTP, LOGL_ERROR,
-		     "GTPv1 control plane socket(domain=%d, type=%d, protocol=%d) failed: Error = %s\n",
-			AF_INET, SOCK_DGRAM, 0, strerror(errno));
-		return -errno;
-	}
-
-	memset(&addr, 0, sizeof(addr));
-	addr.sin_family = AF_INET;
-	addr.sin_addr = *listen;	/* Same IP for user traffic and signalling */
-	addr.sin_port = htons(GTP1C_PORT);
-#if defined(__FreeBSD__) || defined(__APPLE__)
-	addr.sin_len = sizeof(addr);
-#endif
-
-	if (bind((*gsn)->fd1c, (struct sockaddr *)&addr, sizeof(addr)) < 0) {
-		rate_ctr_inc2((*gsn)->ctrg, GSN_CTR_ERR_SOCKET);
-		LOGP_WITH_ADDR(DLGTP, LOGL_ERROR, addr,
-				"bind(fd1c=%d) failed: Error = %s\n",
-				(*gsn)->fd1c, strerror(errno));
-		return -errno;
-	}
+	if (create_and_bind_socket("GTPv1 control plane", *gsn, &(*gsn)->fd1c, AF_INET, listen, GTP1C_PORT) < 0)
+		goto error;
 
 	/* Create GTP version 1 user plane socket */
-	if (((*gsn)->fd1u = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
-		rate_ctr_inc2((*gsn)->ctrg, GSN_CTR_ERR_SOCKET);
-		LOGP(DLGTP, LOGL_ERROR,
-		     "GTPv1 user plane socket(domain=%d, type=%d, protocol=%d) failed: Error = %s\n",
-			AF_INET, SOCK_DGRAM, 0, strerror(errno));
-		return -errno;
-	}
-
-	memset(&addr, 0, sizeof(addr));
-	addr.sin_family = AF_INET;
-	addr.sin_addr = *listen;	/* Same IP for user traffic and signalling */
-	addr.sin_port = htons(GTP1U_PORT);
-#if defined(__FreeBSD__) || defined(__APPLE__)
-	addr.sin_len = sizeof(addr);
-#endif
-
-	if (bind((*gsn)->fd1u, (struct sockaddr *)&addr, sizeof(addr)) < 0) {
-		rate_ctr_inc2((*gsn)->ctrg, GSN_CTR_ERR_SOCKET);
-		LOGP_WITH_ADDR(DLGTP, LOGL_ERROR, addr,
-			"bind(fd1u=%d) failed: Error = %s\n",
-			(*gsn)->fd1u, strerror(errno));
-		return -errno;
-	}
+	if (create_and_bind_socket("GTPv1 user plane", *gsn, &(*gsn)->fd1u, AF_INET, listen, GTP1U_PORT) < 0)
+		goto error;
 
 	/* Start internal queue timer */
 	gtp_queue_timer_start(*gsn);
 
 	return 0;
+error:
+	gtp_free(*gsn);
+	*gsn = NULL;
+	return -1;
 }
 
 int gtp_free(struct gsn_t *gsn)
@@ -593,4 +579,4 @@ int gtp_retranstimeout(struct gsn_t *gsn, struct timeval *timeout)
 	timeout->tv_usec = 0;
 	/* dummy API, deprecated. Return a huge timer to do nothing */
 	return 0;
-}
+}

gtp/gsn.h

@@ -17,6 +17,8 @@
 #include <osmocom/core/timer.h>
 #include <osmocom/core/tdef.h>
 #include <osmocom/core/rate_ctr.h>
+#include <osmocom/gsm/gsm23003.h>
+#include <osmocom/gsm/gsm48.h>
 
 #include "pdp.h"
 
@@ -107,6 +109,7 @@ struct gsn_t {
 	int (*cb_recovery) (struct sockaddr_in * peer, uint8_t recovery);
 	int (*cb_recovery2) (struct sockaddr_in * peer, struct pdp_t * pdp, uint8_t recovery);
 	int (*cb_recovery3) (struct gsn_t *gsn, struct sockaddr_in *peer, struct pdp_t *pdp, uint8_t recovery);
+	int (*cb_sgsn_context_request_ind) (struct gsn_t *gsn, struct sockaddr_in *peer, uint16_t seq, const struct osmo_routing_area_id *rai, uint32_t teic, struct osmo_mobile_identity *mi, union gtpie_member **ie); /* Pass RAI and TLLI/TMSI/IMSI directly */
 
 	/* Counters */
 	struct rate_ctr_group *ctrg;
@@ -130,6 +133,8 @@ extern int gtp_freepdp_teardown(struct gsn_t *gsn, struct pdp_t *pdp);
 extern int gtp_create_context_req(struct gsn_t *gsn, struct pdp_t *pdp,
 				  void *cbp);
 
+extern int gtp_create_sgsn_context_req(struct gsn_t *gsn, struct pdp_t *pdp, void *cbp);
+
 extern int gtp_set_cb_create_context_ind(struct gsn_t *gsn,
 					 int (*cb_create_context_ind) (struct
 								       pdp_t *
@@ -152,6 +157,9 @@ extern int gtp_set_cb_extheader_ind(struct gsn_t *gsn,
 extern int gtp_set_cb_ran_info_relay_ind(struct gsn_t *gsn,
 				    int (*cb) (struct sockaddr_in * peer, union gtpie_member **ie));
 
+extern int gtp_set_cb_sgsn_context_request_ind(struct gsn_t *gsn,
+			     int (*cb) (struct gsn_t *gsn, struct sockaddr_in *peer, uint16_t seq, const struct osmo_routing_area_id *rai, uint32_t teic, struct osmo_mobile_identity *mi, union gtpie_member **ie));
+
 extern int gtp_set_cb_conf(struct gsn_t *gsn,
 			   int (*cb) (int type, int cause, struct pdp_t * pdp,
 				      void *cbp));

gtp/gtp.c

@@ -25,6 +25,8 @@
 
 #include <osmocom/core/logging.h>
 #include <osmocom/core/utils.h>
+#include <osmocom/gsm/gsm48.h>
+#include <osmocom/gsm/gsm23003.h>
 
 #if defined(__FreeBSD__)
 #include <sys/endian.h>
@@ -338,7 +340,7 @@ static uint32_t get_tei(void *pack)
 
 static int gtp_req(struct gsn_t *gsn, uint8_t version, struct pdp_t *pdp,
 	    union gtp_packet *packet, int len,
-	    struct in_addr *inetaddr, void *cbp)
+	    const struct in_addr *inetaddr, void *cbp)
 {
 	uint8_t ver = GTPHDR_F_GET_VER(packet->flags);
 	struct sockaddr_in addr;
@@ -451,9 +453,7 @@ static int gtp_conf(struct gsn_t *gsn, uint8_t version, struct sockaddr_in *peer
 	return 0;
 }
 
-static int gtp_resp(uint8_t version, struct gsn_t *gsn, struct pdp_t *pdp,
-	     union gtp_packet *packet, int len,
-	     struct sockaddr_in *peer, int fd, uint16_t seq, uint64_t tid)
+static int gtp_resp2(struct gsn_t *gsn, union gtp_packet *packet, int len, struct sockaddr_in *peer, int fd, uint16_t seq, uint64_t tid, uint16_t flow, uint32_t tei)
 {
 	uint8_t ver = GTPHDR_F_GET_VER(packet->flags);
 	struct qmsg_t *qmsg;
@@ -462,18 +462,11 @@ static int gtp_resp(uint8_t version, struct gsn_t *gsn, struct pdp_t *pdp,
 		packet->gtp0.h.length = hton16(len - GTP0_HEADER_SIZE);
 		packet->gtp0.h.seq = hton16(seq);
 		packet->gtp0.h.tid = htobe64(tid);
-		if (pdp && ((packet->gtp0.h.type == GTP_GPDU) ||
-			    (packet->gtp0.h.type == GTP_ERROR)))
-			packet->gtp0.h.flow = hton16(pdp->flru);
-		else if (pdp)
-			packet->gtp0.h.flow = hton16(pdp->flrc);
+		packet->gtp0.h.flow = hton16(flow);
 	} else if (ver == 1 && (packet->flags & GTP1HDR_F_SEQ)) {	/* Version 1 with seq */
 		packet->gtp1l.h.length = hton16(len - GTP1_HEADER_SIZE_SHORT);
 		packet->gtp1l.h.seq = hton16(seq);
-		if (pdp && (fd == gsn->fd1u))
-			packet->gtp1l.h.tei = hton32(pdp->teid_gn);
-		else if (pdp)
-			packet->gtp1l.h.tei = hton32(pdp->teic_gn);
+		packet->gtp1l.h.tei = hton32(tei);
 	} else {
 		LOGP(DLGTP, LOGL_ERROR, "Unknown packet flags: 0x%02x\n", packet->flags);
 		return -1;
@@ -485,7 +478,7 @@ static int gtp_resp(uint8_t version, struct gsn_t *gsn, struct pdp_t *pdp,
 	}
 
 	if (sendto(fd, packet, len, 0,
-		   (struct sockaddr *)peer, sizeof(struct sockaddr_in)) < 0) {
+		   (const struct sockaddr *)peer, sizeof(struct sockaddr_in)) < 0) {
 		rate_ctr_inc2(gsn->ctrg, GSN_CTR_ERR_SENDTO);
 		LOGP(DLGTP, LOGL_ERROR,
 			"Sendto(fd=%d, msg=%lx, len=%d) failed: Error = %s\n", fd,
@@ -521,6 +514,32 @@ static int gtp_resp(uint8_t version, struct gsn_t *gsn, struct pdp_t *pdp,
 	return 0;
 }
 
+static int gtp_resp(uint8_t version, struct gsn_t *gsn, struct pdp_t *pdp,
+	     union gtp_packet *packet, int len,
+	     struct sockaddr_in *peer, int fd, uint16_t seq, uint64_t tid)
+{
+	uint8_t ver = GTPHDR_F_GET_VER(packet->flags);
+	uint16_t flow = 0, tei = 0;
+
+	if (ver == 0) {	/* Version 0 */
+		if (pdp && ((packet->gtp0.h.type == GTP_GPDU) ||
+			    (packet->gtp0.h.type == GTP_ERROR)))
+			flow = pdp->flru;
+		else if (pdp)
+			flow = pdp->flrc;
+	} else if (ver == 1 && (packet->flags & GTP1HDR_F_SEQ)) {	/* Version 1 with seq */
+		if (pdp && (fd == gsn->fd1u))
+			tei = pdp->teid_gn;
+		else if (pdp)
+			tei = pdp->teic_gn;
+	} else {
+		LOGP(DLGTP, LOGL_ERROR, "Unknown packet flags: 0x%02x\n", packet->flags);
+		return -1;
+	}
+
+	return gtp_resp2(gsn, packet, len, peer, fd, seq, tid, flow, tei);
+}
+
 static int gtp_notification(struct gsn_t *gsn, uint8_t version,
 		     union gtp_packet *packet, int len,
 		     const struct sockaddr_in *peer, int fd, uint16_t seq)
@@ -820,6 +839,395 @@ int gtp_ran_info_relay_req(struct gsn_t *gsn, const struct sockaddr_in *peer,
 	return gtp_notification(gsn, 1, &packet, length, peer, gsn->fd1c, 0);
 }
 
+#define GSM_MI_TYPE_TLLI 0x05
+
+/* Send an SGSN Context Request for an MI */
+int gtp_sgsn_context_req(struct gsn_t *gsn, const struct in_addr *peer,
+			 const struct osmo_mobile_identity *mi, uint16_t tlli, uint32_t teic,
+			 const struct ul16_t *sgsn_addr, const struct ul255_t *rai, void *cbp)
+{
+	union gtp_packet packet;
+
+	/* GTP 1 is the highest supported protocol */
+	unsigned int length = get_default_gtp(1, GTP_SGSN_CONTEXT_REQ, &packet);
+
+	gtpie_tv0(&packet, &length, GTP_MAX, GTPIE_RAI, rai->l, rai->v);
+	gtpie_tv4(&packet, &length, GTP_MAX, GTPIE_TEI_C, teic);
+	gtpie_tlv(&packet, &length, GTP_MAX, GTPIE_GSN_ADDR, sgsn_addr->l, sgsn_addr->v);
+
+	switch (mi->type) {
+	case GSM_MI_TYPE_IMSI:
+	{
+		uint64_t imsi = gtp_imsi_str2gtp(mi->imsi);
+		imsi = ntoh64(imsi);
+		gtpie_tv8(&packet, &length, GTP_MAX, GTPIE_IMSI, imsi);
+		break;
+	}
+	case GSM_MI_TYPE_TLLI:
+		gtpie_tv4(&packet, &length, GTP_MAX, GTPIE_TLLI, mi->tmsi);
+		break;
+	case GSM_MI_TYPE_TMSI:
+		gtpie_tv4(&packet, &length, GTP_MAX, GTPIE_P_TMSI, mi->tmsi);
+		break;
+	default:
+		return -1;
+		/* TODO: Error */
+		break;
+	}
+
+	return gtp_req(gsn, 1, NULL, &packet, length, peer, cbp);
+}
+
+/* Handle an SGSN Context Request */
+static int gtp_sgsn_context_ind(struct gsn_t *gsn, int version, struct sockaddr_in *peer,
+			void *pack, unsigned len)
+{
+	/* Check if we have a context with TLLI/P-TMSI/IMSI in the RAI */
+	struct osmo_mobile_identity mi = {0};
+	uint64_t imsi;
+
+	union gtpie_member *ie[GTPIE_SIZE];
+	uint32_t teic;
+	uint8_t seq = get_seq(pack);
+	struct ul16_t sgsn_addr;
+	struct ul255_t rai = { .l = 6 };
+	struct osmo_routing_area_id rai_parsed;
+
+	if (version != 1) {
+		LOGP(DLGTP, LOGL_NOTICE,
+			"SGSN Context Request expected only on GTPCv1: %u\n", version);
+		return -EINVAL;
+	}
+
+	int hlen = get_hlen(pack);
+
+	/* Decode information elements */
+	if (gtpie_decaps(ie, version, pack + hlen, len - hlen)) {
+		rate_ctr_inc2(gsn->ctrg, GSN_CTR_PKT_INVALID);
+		GTP_LOGPKG(LOGL_ERROR, peer, pack, len,
+			    "Invalid message format\n");
+		return -EINVAL;
+	}
+
+	/* RAI */
+	if (gtpie_gettv0(ie, GTPIE_RAI, 0, &rai.v, 6)) {
+		GTP_LOGPKG(LOGL_ERROR, peer, pack, len,
+		    "Missing RAI\n");
+		goto missing_ie;
+	}
+	if (osmo_routing_area_id_decode(&rai_parsed, rai.v, 6) < 0) {
+		rate_ctr_inc2(gsn->ctrg, GSN_CTR_PKT_INVALID);
+		GTP_LOGPKG(LOGL_ERROR, peer, pack, len,
+			    "Invalid RAI\n");
+	}
+
+	/* TEI-C */
+	if (gtpie_gettv4(ie, GTPIE_TEI_C, 0, &teic)) {
+		GTP_LOGPKG(LOGL_ERROR, peer, pack, len,
+		    "Missing TEI-C\n");
+		goto missing_ie;
+	}
+
+	/* SGSN address for signalling (mandatory) */
+	if (gtpie_gettlv(ie, GTPIE_GSN_ADDR, 0, &sgsn_addr.l,
+			 &sgsn_addr.v, sizeof(sgsn_addr.v))) {
+		GTP_LOGPKG(LOGL_ERROR, peer, pack, len,
+		    "Missing GSN Addr\n");
+		goto missing_ie;
+	}
+
+	/* Get PTMSI, TLLI or IMSI - only one IE allowed */
+	if (!gtpie_gettv4(ie, GTPIE_TLLI, 0, &mi.tmsi)) {
+		mi.type = GSM_MI_TYPE_TLLI;
+		goto done;
+	}
+
+	if (!gtpie_gettv4(ie, GTPIE_P_TMSI, 0, &mi.tmsi)) {
+		mi.type = GSM_MI_TYPE_TMSI;
+		goto done;
+	}
+
+	if (!gtpie_gettv8(ie, GTPIE_IMSI, 0, &imsi)) {
+		mi.type = GSM_MI_TYPE_IMSI;
+		/* NOTE: gtpie_gettv8 already converts to host byte order, but imsi_gtp2str seems to prefer big endian */
+		imsi = ntoh64(imsi);
+		const char *imsi_str = imsi_gtp2str(&imsi);
+		memcpy(mi.imsi, imsi_str, sizeof(mi.imsi));
+	} else {
+		GTP_LOGPKG(LOGL_ERROR, peer, pack, len,
+		    "Missing Identity information\n");
+		goto missing_ie;
+	}
+
+done:
+	if (gsn->cb_sgsn_context_request_ind)
+		gsn->cb_sgsn_context_request_ind(gsn, peer, seq, &rai_parsed, teic, &mi, ie);
+
+	return 0;
+
+missing_ie:
+	rate_ctr_inc2(gsn->ctrg, GSN_CTR_PKT_MISSING);
+	GTP_LOGPKG(LOGL_ERROR, peer, pack, len,
+		    "Missing mandatory IE\n");
+	/* TODO: Send response with cause */
+	return -EINVAL;
+}
+
+static bool is_ext_ua(const struct pdp_t *pdp)
+{
+	return pdp->eua.l > 0 && pdp->eua.v[0] == PDP_EUA_TYPE_v4v6;
+}
+
+static int gtp_pdp_ctx(uint8_t *buf, unsigned int size, const struct pdp_t *pdp, uint16_t sapi)
+{
+	uint32_t tmp32;
+	uint16_t tmp16;
+	uint8_t *ptr = buf;
+#define CHECK_SPACE_ERR(bytes) \
+	if ((ptr - buf) + (bytes) > size) { \
+		printf("Failed size check: %lu + %lu > %lu\n", (ptr- buf), bytes, size); \
+		return -1; \
+	}
+#define MEMCPY_CHK(dst, src, len) \
+	CHECK_SPACE_ERR((len)) \
+	memcpy((dst), (uint8_t *)(src), (len)); \
+	(dst) += (len);
+
+	// Flags - FIXME: No ASI
+	*ptr++ = (is_ext_ua(pdp) << 7) | ((!!pdp->vplmn_allow) << 6) | ((!!pdp->reorder) << 4) | (pdp->nsapi & 0x0f);
+	// SAPI
+	*ptr++ = sapi & 0x0f;
+
+	// QoS Sub
+	if (pdp->qos_sub.l < 4) {
+		/* Work around qos_sub never being set */
+		*ptr++ = 4;
+		*ptr++ = 0;
+		*ptr++ = 0x23;
+		*ptr++ = 0x02;
+		*ptr++ = 0x00;
+	} else {
+		*ptr++ = pdp->qos_sub.l;
+		MEMCPY_CHK(ptr, pdp->qos_sub.v, pdp->qos_sub.l);
+	}
+	// QoS Req
+	*ptr++ = pdp->qos_req.l;
+	MEMCPY_CHK(ptr, pdp->qos_req.v, pdp->qos_req.l);
+	// QoS Neg
+	*ptr++ = pdp->qos_neg.l;
+	MEMCPY_CHK(ptr, pdp->qos_neg.v, pdp->qos_neg.l);
+
+	// SND
+	tmp16 = osmo_htons(pdp->pdcpsndd);
+	MEMCPY_CHK(ptr, &tmp16, sizeof(tmp16));
+	// SNU
+	tmp16 = osmo_htons(pdp->pdcpsndu);
+	MEMCPY_CHK(ptr, &tmp16, sizeof(tmp16));
+	// Send N-PDU
+	*ptr++ = pdp->gtpsntx;
+	// Recv N-PDU
+	*ptr++ = pdp->gtpsnrx;
+	// Uplink TEIC
+	tmp32 = osmo_htonl(pdp->teic_gn);
+	MEMCPY_CHK(ptr, &tmp32, sizeof(tmp32));
+	// Uplink TEIDI
+	tmp32 = osmo_htonl(pdp->teid_gn);
+	MEMCPY_CHK(ptr, &tmp32, sizeof(tmp32));
+	// PDP Ctx Id
+	*ptr++ = pdp->pdp_id;
+	// PDP Type Org
+	*ptr++ = PDP_EUA_ORG_IETF;
+
+	// PDP Type No.
+	// PDP Address
+	switch (pdp->eua.v[1]) {
+	case PDP_EUA_TYPE_v4:
+	case PDP_EUA_TYPE_v4v6:
+		/* v4v6 expects an IPv4 addr first followed by an IPv6 addr*/
+		*ptr++ = PDP_EUA_TYPE_v4;
+		if (pdp->eua.l < 6)
+			return -1;
+		*ptr++ = 4;
+		MEMCPY_CHK(ptr, &pdp->eua.v[2], 4);
+		break;
+	case PDP_EUA_TYPE_v6:
+		*ptr++ = PDP_EUA_TYPE_v6;
+		if (pdp->eua.l < 18)
+			return -1;
+		*ptr++ = 16;
+		MEMCPY_CHK(ptr, &pdp->eua.v[2], 16);
+		break;
+	default:
+		return -EINVAL;
+		//Panic
+	}
+	// GGSN Address Ctrl
+	*ptr++ = pdp->gsnrc.l;
+	MEMCPY_CHK(ptr, pdp->gsnrc.v, pdp->gsnrc.l);
+	// GGSN Address User
+	*ptr++ = pdp->gsnru.l;
+	MEMCPY_CHK(ptr, pdp->gsnru.v, pdp->gsnru.l);
+	// APN
+	*ptr++ = pdp->apn_use.l;
+	MEMCPY_CHK(ptr, pdp->apn_use.v, pdp->apn_use.l);
+	// TransId
+	*ptr++ = (pdp->ti >> 8) & 0x0f;
+	*ptr++ = pdp->ti & 0xff;
+
+	if (is_ext_ua(pdp)) {
+		*ptr++ = PDP_EUA_TYPE_v6;
+		if (pdp->eua.l < 22)
+			return -1;
+		*ptr++ = 16;
+		MEMCPY_CHK(ptr, &pdp->eua.v[6], 16);
+	}
+	return ptr - buf;
+#undef CHECK_SPACE_ERR
+#undef MEMCPY_CHK
+}
+
+int gtp_sgsn_context_conf(struct gsn_t *gsn, struct sockaddr_in *peer, uint16_t seq,
+			 uint32_t teic, uint8_t cause, uint64_t imsi, const struct in_addr *sgsn_addr, struct pdp_t *pdpctx, uint16_t sapi, uint8_t *mmctx, int mm_len, void *cbp)
+{
+	union gtp_packet packet;
+	struct ul255_t pdp;
+
+	/* GTP 1 is the highest supported protocol */
+	unsigned int length = get_default_gtp(1, GTP_SGSN_CONTEXT_RSP, &packet);
+
+	// Cause - TV1
+	gtpie_tv1(&packet, &length, GTP_MAX, GTPIE_CAUSE, cause);
+
+	if (cause != GTPCAUSE_ACC_REQ)
+		return gtp_resp2(gsn, &packet, length, peer, gsn->fd1c, seq, 0, 0, teic);
+
+	// IMSI - TV8
+	gtpie_tv8(&packet, &length, GTP_MAX, GTPIE_IMSI, imsi);
+
+	// TEIC - TV4
+	gtpie_tv4(&packet, &length, GTP_MAX, GTPIE_TEI_C, pdpctx->teic_own);
+
+	// MM Ctx - TLV
+	gtpie_tlv(&packet, &length, GTP_MAX, GTPIE_MM_CONTEXT, mm_len, mmctx);
+
+	// PDP Ctx - TLV
+	if (pdpctx) {
+		int rc = gtp_pdp_ctx(pdp.v, 255, pdpctx, sapi);
+		if (rc > 0)
+			gtpie_tlv(&packet, &length, GTP_MAX, GTPIE_PDP_CONTEXT, rc, pdp.v);
+	}
+
+	// SGSN Addr Ctrl - TLV
+	gtpie_tlv(&packet, &length, GTP_MAX, GTPIE_GSN_ADDR, 4, &sgsn_addr->s_addr);
+
+	// Alt GGSN Addr Ctrl (per PDP Ctx)
+	// Alt GGSN Addr User (per PDP Ctx)
+	/* The encoding for this is a bit insane */
+
+	return gtp_resp2(gsn, &packet, length, peer, gsn->fd1c, seq, 0, 0, teic);
+}
+
+/* Handle an SGSN Context Response */
+static int gtp_sgsn_context_conf_ind(struct gsn_t *gsn, int version, struct sockaddr_in *peer,
+			void *pack, unsigned len)
+{
+	/** If cause is "Request accepted": Send ACK,
+	    else: Log and handle error */
+
+	/* Check if we have a context with TLLI/P-TMSI/IMSI in the RAI */
+
+	void *cbp = NULL;
+	uint8_t type = 0;
+	uint8_t cause;
+	union gtpie_member *ie[GTPIE_SIZE];
+	struct pdp_t *pdp = NULL;
+	uint32_t teic;
+	struct ul16_t sgsn_addr;
+
+	if (version != 1) {
+		LOGP(DLGTP, LOGL_NOTICE,
+			"SGSN Context Request expected only on GTPCv1: %u\n", version);
+		return -EINVAL;
+	}
+
+	int hlen = get_hlen(pack);
+
+	/* Remove packet from queue */
+	if (gtp_conf(gsn, version, peer, pack, len, &type, &cbp))
+		return EOF;
+
+	/* Extract information elements into a pointer array */
+	if (gtpie_decaps(ie, version, pack + hlen, len - hlen)) {
+		rate_ctr_inc2(gsn->ctrg, GSN_CTR_PKT_INVALID);
+		GTP_LOGPKG(LOGL_ERROR, peer, pack, len,
+			    "Invalid message format\n");
+		if (gsn->cb_conf)
+			gsn->cb_conf(type, EOF, NULL, cbp);
+		return EOF;
+	}
+
+	/* Extract cause value (mandatory) */
+	if (gtpie_gettv1(ie, GTPIE_CAUSE, 0, &cause)) {
+		rate_ctr_inc2(gsn->ctrg, GSN_CTR_PKT_MISSING);
+		GTP_LOGPKG(LOGL_ERROR, peer, pack, len,
+			    "Missing mandatory information field\n");
+		if (gsn->cb_conf)
+			gsn->cb_conf(type, EOF, NULL, cbp);
+		return EOF;
+	}
+
+	/* Check all conditional information elements */
+	if (!gtp_cause_successful(cause)) {
+		GTP_LOGPKG(LOGL_NOTICE, peer, pack, len,
+			    "SGSN Context response with cause (%u)\n", cause);
+		if (gsn->cb_conf)
+			gsn->cb_conf(type, cause, NULL, cbp);
+	}
+
+	/* Gather UE context and PDP data, create pdp context */
+	//gtp_pdp_newpdp(gsn, &pdp, imsi, nsapi, NULL)
+	if (gsn->cb_conf)
+		gsn->cb_conf(type, cause, pdp, cbp);
+
+	return 0;
+}
+
+/* Handle an SGSN Context Acknowledge */
+static int gtp_sgsn_context_ack(struct gsn_t *gsn, int version, struct sockaddr_in *peer,
+			void *pack, unsigned len)
+{
+	/* If cause is != Request accepted, log error */
+	return -ENOTSUP;
+}
+
+/* Handle an SGSN Context request */
+int gtp_context_request(struct gsn_t *gsn, int version, struct sockaddr_in *peer,
+			void *pack, unsigned len)
+{
+	union gtpie_member *ie[GTPIE_SIZE];
+
+	if (version != 1) {
+		LOGP(DLGTP, LOGL_NOTICE,
+			"SGSN Context Request expected only on GTPCv1: %u\n", version);
+		return -EINVAL;
+	}
+
+	int hlen = get_hlen(pack);
+
+	/* Decode information elements */
+	if (gtpie_decaps(ie, version, pack + hlen, len - hlen)) {
+		rate_ctr_inc2(gsn->ctrg, GSN_CTR_PKT_INVALID);
+		GTP_LOGPKG(LOGL_ERROR, peer, pack, len,
+			    "Invalid message format (AN Information Relay)\n");
+		return -EINVAL;
+	}
+
+	if (gsn->cb_ran_info_relay_ind)
+		gsn->cb_ran_info_relay_ind(peer, ie);
+
+	return 0;
+}
+
 /* ***********************************************************
  * Session management messages
  * Messages: create, update and delete PDP context
@@ -995,7 +1403,7 @@ int gtp_create_context_resp(struct gsn_t *gsn, struct pdp_t *pdp, int cause)
 	/* Now send off a reply to the peer */
 	gtp_create_pdp_resp(gsn, pdp->version, pdp, cause);
 
-	if (cause != GTPCAUSE_ACC_REQ)
+	if (!gtp_cause_successful(cause))
 		gtp_freepdp(gsn, pdp);
 
 	return 0;
@@ -1011,7 +1419,7 @@ int gtp_create_pdp_resp(struct gsn_t *gsn, int version, struct pdp_t *pdp,
 
 	gtpie_tv1(&packet, &length, GTP_MAX, GTPIE_CAUSE, cause);
 
-	if (cause == GTPCAUSE_ACC_REQ) {
+	if (gtp_cause_successful(cause)) {
 
 		if (version == 0)
 			gtpie_tv0(&packet, &length, GTP_MAX, GTPIE_QOS_PROFILE0,
@@ -1445,7 +1853,7 @@ int gtp_create_pdp_conf(struct gsn_t *gsn, int version,
 	}
 
 	/* Check all conditional information elements */
-	if (GTPCAUSE_ACC_REQ == cause) {
+	if (gtp_cause_successful(cause)) {
 
 		if (version == 0) {
 			if (gtpie_gettv0(ie, GTPIE_QOS_PROFILE0, 0,
@@ -1667,7 +2075,7 @@ static int gtp_update_pdp_resp(struct gsn_t *gsn, uint8_t version,
 
 	gtpie_tv1(&packet, &length, GTP_MAX, GTPIE_CAUSE, cause);
 
-	if (cause == GTPCAUSE_ACC_REQ) {
+	if (gtp_cause_successful(cause)) {
 
 		if (version == 0)
 			gtpie_tv0(&packet, &length, GTP_MAX, GTPIE_QOS_PROFILE0,
@@ -1997,7 +2405,7 @@ static int gtp_update_pdp_conf(struct gsn_t *gsn, uint8_t version,
 
 	/* Check all conditional information elements */
 	/* TODO: This does not handle GGSN-initiated update responses */
-	if (cause == GTPCAUSE_ACC_REQ) {
+	if (gtp_cause_successful(cause)) {
 		if (version == 0) {
 			if (gtpie_gettv0(ie, GTPIE_QOS_PROFILE0, 0,
 					 &pdp->qos_neg0,
@@ -2172,7 +2580,7 @@ int gtp_delete_pdp_resp(struct gsn_t *gsn, int version,
 	gtp_resp(version, gsn, pdp, &packet, length, peer, fd,
 		 get_seq(pack), get_tid(pack));
 
-	if (cause == GTPCAUSE_ACC_REQ) {
+	if (gtp_cause_successful(cause)) {
 		if ((teardown) || (version == 0)) {	/* Remove all contexts */
 			gtp_freepdp_teardown(gsn, linked_pdp);
 		} else {
@@ -2198,7 +2606,6 @@ int gtp_delete_pdp_resp(struct gsn_t *gsn, int version,
 			}
 		}
 	}
-	/* if (cause == GTPCAUSE_ACC_REQ) */
 	return 0;
 }
 
@@ -2350,7 +2757,7 @@ int gtp_delete_pdp_conf(struct gsn_t *gsn, int version,
 	}
 
 	/* Check the cause value (again) */
-	if ((GTPCAUSE_ACC_REQ != cause) && (GTPCAUSE_NON_EXIST != cause)) {
+	if (!gtp_cause_successful(cause) && (GTPCAUSE_NON_EXIST != cause)) {
 		rate_ctr_inc2(gsn->ctrg, GSN_CTR_ERR_UNEXPECTED_CAUSE);
 		GTP_LOGPKG(LOGL_ERROR, peer, pack, len,
 			    "Unexpected cause value received: %d\n", cause);
@@ -2827,6 +3234,15 @@ int gtp_decaps1c(struct gsn_t *gsn)
 		case GTP_RAN_INFO_RELAY:
 			gtp_ran_info_relay_ind(gsn, version, &peer, buffer, status);
 			break;
+		case GTP_SGSN_CONTEXT_REQ:
+			gtp_sgsn_context_ind(gsn, version, &peer, buffer, status);
+			break;
+		case GTP_SGSN_CONTEXT_RSP:
+			gtp_sgsn_context_conf_ind(gsn, version, &peer, buffer, status);
+			break;
+		case GTP_SGSN_CONTEXT_ACK:
+			gtp_sgsn_context_ack(gsn, version, &peer, buffer, status);
+			break;
 		default:
 			rate_ctr_inc2(gsn->ctrg, GSN_CTR_PKT_UNKNOWN);
 			GTP_LOGPKG(LOGL_ERROR, &peer, buffer, status,

gtp/gtp.h

@@ -53,7 +53,7 @@
 #define GTP_UPDATE_PDP_RSP   19	/* Update PDP Context Response */
 #define GTP_DELETE_PDP_REQ   20	/* Delete PDP Context Request */
 #define GTP_DELETE_PDP_RSP   21	/* Delete PDP Context Response */
-						       /* 22-25 For future use. *//* In version GTP 1 anonomous PDP context */
+/* 22-25 For future use. *//* In version GTP 1 anonomous PDP context */
 #define GTP_ERROR            26	/* Error Indication */
 #define GTP_PDU_NOT_REQ      27	/* PDU Notification Request */
 #define GTP_PDU_NOT_RSP      28	/* PDU Notification Response */
@@ -99,19 +99,21 @@ static inline const char *gtp_type_name(uint8_t val)
 #define GTPCAUSE_NO_ID_NEEDED               3	/* No identity needed */
 #define GTPCAUSE_MS_REFUSES_X               4	/* MS refuses */
 #define GTPCAUSE_MS_NOT_RESP_X              5	/* MS is not GPRS responding */
-#define GTPCAUSE_006                        6	/* For future use 6-48 */
-#define GTPCAUSE_049                       49	/* Cause values reserved for GPRS charging protocol use (See GTP' in GSM 12.15) 49-63 */
-#define GTPCAUSE_064                       64	/* For future use 64-127 */
+/* 6-48 For future use */
+/* 49-63 Cause values reserved for GPRS charging protocol use (See GTP' in GSM 12.15) */
+/* 64-127 For future use */
 #define GTPCAUSE_ACC_REQ                  128	/* Request accepted */
-#define GTPCAUSE_129                      129	/* For future use 129-176 */
-#define GTPCAUSE_177                      177	/* Cause values reserved for GPRS charging protocol use (See GTP' In GSM 12.15) 177-191 */
+#define GTPCAUSE_NEW_PDP_NET_PREF         129	/* New PDP type due to network preference */
+#define GTPCAUSE_NEW_PDP_ADDR_BEAR        130	/* New PDP type due to single address bearer only */
+/* 131-176 For future use */
+/* 177-191 Cause values reserved for GPRS charging protocol use (See GTP' In GSM 12.15) */
 #define GTPCAUSE_NON_EXIST                192	/* Non-existent */
 #define GTPCAUSE_INVALID_MESSAGE          193	/* Invalid message format */
 #define GTPCAUSE_IMSI_NOT_KNOWN           194	/* IMSI not known */
 #define GTPCAUSE_MS_DETACHED              195	/* MS is GPRS detached */
 #define GTPCAUSE_MS_NOT_RESP              196	/* MS is not GPRS responding */
 #define GTPCAUSE_MS_REFUSES               197	/* MS refuses */
-#define GTPCAUSE_198                      198	/* For future use */
+/* 198 For future use */
 #define GTPCAUSE_NO_RESOURCES             199	/* No resources available */
 #define GTPCAUSE_NOT_SUPPORTED            200	/* Service not supported */
 #define GTPCAUSE_MAN_IE_INCORRECT         201	/* Mandatory IE incorrect */
@@ -134,8 +136,15 @@ static inline const char *gtp_type_name(uint8_t val)
 #define GTPCAUSE_SYN_ERR_FILTER           218	/* Syntactic errors in packet filter(s) */
 #define GTPCAUSE_MISSING_APN              219	/* Missing or unknown APN */
 #define GTPCAUSE_UNKNOWN_PDP              220	/* Unknown PDP address or PDP type */
-#define GTPCAUSE_221                      221	/* For Future Use 221-240 */
-#define GTPCAUSE_241                      241	/* Cause Values Reserved For Gprs Charging Protocol Use (See Gtp' In Gsm 12.15) 241-255 */
+/* 221-240 For future use */
+/* 241-255 Cause Values Reserved For Gprs Charging Protocol Use (See Gtp' In Gsm 12.15) */
+
+static inline bool gtp_cause_successful(uint8_t cause)
+{
+	return cause == GTPCAUSE_ACC_REQ ||
+		cause == GTPCAUSE_NEW_PDP_NET_PREF ||
+		cause == GTPCAUSE_NEW_PDP_ADDR_BEAR;
+}
 
 struct ul66_t;
 struct ul16_t;
@@ -253,6 +262,12 @@ extern int gtp_ran_info_relay_req(struct gsn_t *gsn, const struct sockaddr_in *p
 				  const uint8_t *rim_route_addr, size_t rim_route_addr_len,
 				  uint8_t rim_route_addr_discr);
 
+extern int gtp_sgsn_context_req(struct gsn_t *gsn, const struct in_addr *peer,
+			 const struct osmo_mobile_identity *mi, uint16_t tlli, uint32_t teic,
+			 const struct ul16_t *sgsn_addr, const struct ul255_t *rai, void *cbp);
+extern int gtp_sgsn_context_conf(struct gsn_t *gsn, struct sockaddr_in *peer, uint16_t seq,
+			 uint32_t teic, uint8_t cause, uint64_t imsi, const struct in_addr *sgsn_addr, struct pdp_t *pdpctx, uint16_t sapi, uint8_t *mmctx, int mm_len, void *cbp);
+
 extern int gtp_decaps0(struct gsn_t *gsn);
 extern int gtp_decaps1c(struct gsn_t *gsn);
 extern int gtp_decaps1u(struct gsn_t *gsn);

lib/Makefile.am

@@ -1,10 +1,41 @@
 noinst_LIBRARIES = libmisc.a
 
-noinst_HEADERS = gnugetopt.h ippool.h lookup.h syserr.h tun.h in46_addr.h netdev.h gtp-kernel.h netns.h util.h icmpv6.h checksum.h
+noinst_HEADERS = \
+		 checksum.h \
+		 gnugetopt.h \
+		 gtp-kernel.h \
+		 icmpv6.h \
+		 in46_addr.h \
+		 ippool.h \
+		 lookup.h \
+		 netdev.h \
+		 netns.h \
+		 syserr.h \
+		 tun.h \
+		 util.h \
+		 $(NULL)
 
-AM_CFLAGS = -O2 -fno-builtin -Wall -DSBINDIR='"$(sbindir)"' -ggdb $(LIBOSMOCORE_CFLAGS)
+AM_CFLAGS = \
+	    -fno-builtin \
+	    -Wall \
+	    -DSBINDIR='"$(sbindir)"' \
+	    $(LIBOSMOCORE_CFLAGS) \
+	    $(NULL)
 
-libmisc_a_SOURCES = getopt1.c getopt.c ippool.c lookup.c tun.c debug.c in46_addr.c netdev.c netns.c util.c icmpv6.c checksum.c
+libmisc_a_SOURCES = \
+		    checksum.c \
+		    debug.c \
+		    getopt.c \
+		    getopt1.c \
+		    icmpv6.c \
+		    in46_addr.c \
+		    ippool.c \
+		    lookup.c \
+		    netdev.c \
+		    netns.c \
+		    tun.c \
+		    util.c \
+		    $(NULL)
 
 if ENABLE_GTP_KERNEL
 AM_CFLAGS += -DGTP_KERNEL $(LIBGTPNL_CFLAGS)

lib/gtp-kernel.c

@@ -104,61 +104,97 @@ void gtp_kernel_stop(const char *devname)
 
 int gtp_kernel_tunnel_add(struct pdp_t *pdp, const char *devname)
 {
-	struct in_addr ms, sgsn;
+	int ms_addr_count;
+	struct in46_addr ms[2];
+	struct in46_addr sgsn;
 	struct gtp_tunnel *t;
-	int ret;
+	int ret = 0;
 
 	pdp_debug(__func__, devname, pdp);
 
-	t = gtp_tunnel_alloc();
-	if (t == NULL)
+	in46a_from_gsna(&pdp->gsnrc, &sgsn);
+
+	ms_addr_count = in46a_from_eua(&pdp->eua, ms);
+	if (ms_addr_count < 0)
 		return -1;
 
-	memcpy(&ms, &pdp->eua.v[2], sizeof(struct in_addr));
-	memcpy(&sgsn, &pdp->gsnrc.v[0], sizeof(struct in_addr));
+	for (int i = 0; i < ms_addr_count; i++) {
+		t = gtp_tunnel_alloc();
+		if (t == NULL)
+			return -1;
 
-	gtp_tunnel_set_ifidx(t, if_nametoindex(devname));
-	gtp_tunnel_set_version(t, pdp->version);
-	gtp_tunnel_set_ms_ip4(t, &ms);
-	gtp_tunnel_set_sgsn_ip4(t, &sgsn);
-	if (pdp->version == 0) {
-		gtp_tunnel_set_tid(t, pdp_gettid(pdp->imsi, pdp->nsapi));
-		gtp_tunnel_set_flowid(t, pdp->flru);
-	} else {
-		gtp_tunnel_set_i_tei(t, pdp->teid_own);
-		/* use the TEI advertised by SGSN when sending packets
-		 * towards the SGSN */
-		gtp_tunnel_set_o_tei(t, pdp->teid_gn);
+		gtp_tunnel_set_ifidx(t, if_nametoindex(devname));
+		gtp_tunnel_set_version(t, pdp->version);
+
+		if (in46a_to_af(&ms[i]) == AF_INET)
+			gtp_tunnel_set_ms_ip4(t, &ms[i].v4);
+		else {
+			/* In IPv6, EUA doesn't contain the actual IP
+			 * addr/prefix. Set higher bits to 0 to get the 64 bit
+			 * netmask. */
+			memset(((void *)&ms[i].v6) + 8, 0, 8);
+			gtp_tunnel_set_ms_ip6(t, &ms[i].v6);
+		}
+
+		if (in46a_to_af(&sgsn) == AF_INET)
+			gtp_tunnel_set_sgsn_ip4(t, &sgsn.v4);
+		else
+			gtp_tunnel_set_sgsn_ip6(t, &sgsn.v6);
+
+		if (pdp->version == 0) {
+			gtp_tunnel_set_tid(t, pdp_gettid(pdp->imsi, pdp->nsapi));
+			gtp_tunnel_set_flowid(t, pdp->flru);
+		} else {
+			gtp_tunnel_set_i_tei(t, pdp->teid_own);
+			/* use the TEI advertised by SGSN when sending packets
+			 * towards the SGSN */
+			gtp_tunnel_set_o_tei(t, pdp->teid_gn);
+		}
+
+		ret = gtp_add_tunnel(gtp_nl.genl_id, gtp_nl.nl, t);
+		gtp_tunnel_free(t);
+
+		if (ret != 0)
+			break;
 	}
 
-	ret = gtp_add_tunnel(gtp_nl.genl_id, gtp_nl.nl, t);
-	gtp_tunnel_free(t);
-
 	return ret;
 }
 
 int gtp_kernel_tunnel_del(struct pdp_t *pdp, const char *devname)
 {
+	int ms_addr_count;
+	struct in46_addr ms[2];
 	struct gtp_tunnel *t;
-	int ret;
+	int ret = 0;
 
 	pdp_debug(__func__, devname, pdp);
 
-	t = gtp_tunnel_alloc();
-	if (t == NULL)
+	ms_addr_count = in46a_from_eua(&pdp->eua, ms);
+	if (ms_addr_count < 0)
 		return -1;
 
-	gtp_tunnel_set_ifidx(t, if_nametoindex(devname));
-	gtp_tunnel_set_version(t, pdp->version);
-	if (pdp->version == 0) {
-		gtp_tunnel_set_tid(t, pdp_gettid(pdp->imsi, pdp->nsapi));
-		gtp_tunnel_set_flowid(t, pdp->flru);
-	} else {
-		gtp_tunnel_set_i_tei(t, pdp->teid_own);
-	}
+	for (int i = 0; i < ms_addr_count; i++) {
+		t = gtp_tunnel_alloc();
+		if (t == NULL)
+			return -1;
 
-	ret = gtp_del_tunnel(gtp_nl.genl_id, gtp_nl.nl, t);
-	gtp_tunnel_free(t);
+		gtp_tunnel_set_ifidx(t, if_nametoindex(devname));
+		gtp_tunnel_set_family(t, in46a_to_af(&ms[i]));
+		gtp_tunnel_set_version(t, pdp->version);
+		if (pdp->version == 0) {
+			gtp_tunnel_set_tid(t, pdp_gettid(pdp->imsi, pdp->nsapi));
+			gtp_tunnel_set_flowid(t, pdp->flru);
+		} else {
+			gtp_tunnel_set_i_tei(t, pdp->teid_own);
+		}
+
+		ret = gtp_del_tunnel(gtp_nl.genl_id, gtp_nl.nl, t);
+		gtp_tunnel_free(t);
+
+		if (ret != 0)
+			break;
+	}
 
 	return ret;
 }

lib/icmpv6.h

@@ -44,10 +44,9 @@ struct icmpv6_radv_hdr {
 	uint8_t res:6,
 		m:1,
 		o:1;
-#else
-	uint8_t m:1,
-		o:1,
-		res:6;
+#elif OSMO_IS_BIG_ENDIAN
+/* auto-generated from the little endian part above (libosmocore/contrib/struct_endianness.py) */
+	uint8_t o:1, m:1, res:6;
 #endif
 	uint16_t router_lifetime;
 	uint32_t reachable_time;
@@ -72,10 +71,9 @@ struct icmpv6_opt_prefix {
 	uint8_t res:6,
 		a:1,
 		l:1;
-#else
-	uint8_t l:1,
-		a:1,
-		res:6;
+#elif OSMO_IS_BIG_ENDIAN
+/* auto-generated from the little endian part above (libosmocore/contrib/struct_endianness.py) */
+	uint8_t l:1, a:1, res:6;
 #endif
 	uint32_t valid_lifetime;
 	uint32_t preferred_lifetime;

lib/in46_addr.c

@@ -375,3 +375,10 @@ default_to_dyn_v4:
 	dst->v4.s_addr = 0;
 	return 1;
 }
+
+void in46a_from_gsna(const struct ul16_t *in, struct in46_addr *dst)
+{
+	dst->len = in->l;
+	OSMO_ASSERT(in->l <= sizeof(dst->v6));
+	memcpy(&dst->v6, in->v, in->l);
+}

lib/in46_addr.h

@@ -39,3 +39,5 @@ static inline bool in46a_is_v6(const struct in46_addr *addr) {
 static inline bool in46a_is_v4(const struct in46_addr *addr) {
 	return addr->len == sizeof(struct in_addr);
 }
+
+void in46a_from_gsna(const struct ul16_t *in, struct in46_addr *dst);

sgsnemu/Makefile.am

@@ -2,12 +2,21 @@ bin_PROGRAMS = sgsnemu
 
 AM_LDFLAGS = @EXEC_LDFLAGS@
 
-AM_CFLAGS = -O2 -D_GNU_SOURCE -fno-builtin -Wall -DSBINDIR='"$(sbindir)"' -ggdb $(LIBOSMOCORE_CFLAGS)
+AM_CFLAGS = \
+	    -D_GNU_SOURCE \
+	    -fno-builtin \
+	    -Wall \
+	    -DSBINDIR='"$(sbindir)"' \
+	    $(LIBOSMOCORE_CFLAGS) \
+	    $(NULL)
 
 sgsnemu_LDADD = @EXEC_LDADD@ -lgtp -L../gtp ../lib/libmisc.a $(LIBOSMOCORE_LIBS)
 
 if ENABLE_GTP_KERNEL
-AM_CFLAGS += -DGTP_KERNEL $(LIBGTPNL_CFLAGS)
+AM_CFLAGS += \
+	     -DGTP_KERNEL \
+	     $(LIBGTPNL_CFLAGS) \
+	     $(NULL)
 sgsnemu_LDADD += $(LIBGTPNL_LIBS)
 endif
 

tests/gtp/Makefile.am

@@ -1,4 +1,9 @@
-AM_CFLAGS = -Wall -I$(top_srcdir)/include $(LIBOSMOCORE_CFLAGS) -g
+AM_CFLAGS = \
+	    -Wall \
+	    -I$(top_srcdir)/include \
+	    $(LIBOSMOCORE_CFLAGS) \
+	    $(NULL)
+AM_LDFLAGS = -no-install
 
 EXTRA_DIST = \
 	gtpie_test.ok \

tests/lib/Makefile.am

@@ -1,4 +1,9 @@
-AM_CFLAGS = -Wall -I$(top_srcdir)/include $(LIBOSMOCORE_CFLAGS) -g
+AM_CFLAGS = \
+	    -Wall \
+	    -I$(top_srcdir)/include \
+	    $(LIBOSMOCORE_CFLAGS) \
+	    $(NULL)
+AM_LDFLAGS = -no-install
 
 EXTRA_DIST = ippool_test.ok \
 	     ippool_test.err \