Implement AoIP, port to M3UA SIGTRAN (large addition and refactoring)

This was originally a long series of commits converging to the final result
seen in this patch. It does not make much sense to review the smaller steps'
trial and error, we need to review this entire change as a whole.

Implement AoIP in osmo-msc and osmo-bsc.

Change over to the new libosmo-sigtran API with support for proper
SCCP/M3UA/SCTP stacking, as mandated by 3GPP specifications for the IuCS and
IuPS interfaces.

From here on, a separate osmo-stp process is required for SCCP routing between
OsmoBSC / OsmoHNBGW <-> OsmoMSC / OsmoSGSN

jenkins.sh: build from libosmo-sccp and osmo-iuh master branches now for new
M3UA SIGTRAN.

Patch-by: pmaier, nhofmeyr, laforge
Change-Id: I5ae4e05ee7c57cad341ea5e86af37c1f6b0ffa77

1 files changed, 76 insertions, 5 deletions

diff --git a/src/osmo-msc/msc_main.c b/src/osmo-msc/msc_main.c
index 723c0e6e8..cd713eee6 100644
--- a/src/osmo-msc/msc_main.c
+++ b/src/osmo-msc/msc_main.c
@@ -63,6 +63,7 @@
 #include <openbsc/ctrl.h>
 #include <openbsc/osmo_bsc_rf.h>
 #include <openbsc/smpp.h>
+#include <osmocom/sigtran/osmo_ss7.h>
 #include <openbsc/mgcpgw_client.h>
 
 #include <openbsc/msc_ifaces.h>
@@ -70,6 +71,7 @@
 #include <openbsc/iu.h>
 #include <openbsc/iucs.h>
 #include <openbsc/iucs_ranap.h>
+#include <openbsc/a_iface.h>
 
 static const char * const osmomsc_copyright =
 	"OsmoMSC - Osmocom Circuit-Switched Core Network implementation\r\n"
@@ -310,8 +312,7 @@ static struct vty_app_info msc_vty_info = {
 	.is_config_node	= bsc_vty_is_config_node,
 };
 
-static int rcvmsg_iu_cs(struct msgb *msg, struct gprs_ra_id *ra_id,
-			uint16_t *sai)
+static int rcvmsg_iu_cs(struct msgb *msg, struct gprs_ra_id *ra_id, uint16_t *sai)
 {
 	DEBUGP(DIUCS, "got IuCS message"
 	       " %d bytes: %s\n",
@@ -334,6 +335,68 @@ static int rx_iu_event(struct ue_conn_ctx *ctx, enum iu_event_type type,
 	return iucs_rx_ranap_event(msc_network, ctx, type, data);
 }
 
+#define DEFAULT_M3UA_REMOTE_IP "127.0.0.1"
+#define DEFAULT_PC_A "0.23.1"
+#define DEFAULT_PC_IU "0.23.2"
+#define DEFAULT_PC_A_IU DEFAULT_PC_A
+
+static struct osmo_sccp_instance *sccp_setup(void *ctx, uint32_t cs7_instance,
+					     const char *label, const char *default_pc_str)
+{
+	int default_pc = osmo_ss7_pointcode_parse(NULL, default_pc_str);
+	if (default_pc < 0)
+		return NULL;
+
+	return osmo_sccp_simple_client_on_ss7_id(ctx, cs7_instance, label, default_pc,
+						 OSMO_SS7_ASP_PROT_M3UA,
+						 0, NULL, /* local: use arbitrary port and 0.0.0.0. */
+						 0, /* remote: use protocol default port */
+						 DEFAULT_M3UA_REMOTE_IP);
+	/* Note: If a differing remote IP is to be used, it was already entered in the vty config at
+	 * 'cs7' / 'asp' / 'remote-ip', and this default remote IP has no effect.
+	 * Similarly, 'cs7' / 'listen' can specify the local IP address. */
+}
+
+static int ss7_setup(void *ctx)
+{
+	uint32_t cs7_instance_a = msc_network->a.cs7_instance;
+#if BUILD_IU
+	uint32_t cs7_instance_iu = msc_network->iu.cs7_instance;
+
+	if (cs7_instance_a == cs7_instance_iu) {
+		/* Create one single SCCP instance which will be used for both,
+		 * Iu and A at the same time, under the same point-code */
+		LOGP(DMSC, LOGL_NOTICE, "CS7 Instance identifiers: A = Iu = %u\n", cs7_instance_a);
+
+		msc_network->a.sccp = sccp_setup(ctx, cs7_instance_a, "OsmoMSC-A-Iu", DEFAULT_PC_A_IU);
+		if (!msc_network->a.sccp)
+			return -EINVAL;
+
+		msc_network->iu.sccp = msc_network->a.sccp;
+	} else {
+		/* Create two separate SCCP instances to run A and Iu independently on different
+		 * pointcodes */
+		LOGP(DMSC, LOGL_NOTICE, "CS7 Instance identifiers: A = %u, Iu = %u\n",
+		     cs7_instance_a, cs7_instance_iu);
+
+		msc_network->a.sccp = sccp_setup(ctx, cs7_instance_a, "OsmoMSC-A", DEFAULT_PC_A);
+		if (!msc_network->a.sccp)
+			return -EINVAL;
+
+		msc_network->iu.sccp = sccp_setup(ctx, cs7_instance_iu, "OsmoMSC-Iu", DEFAULT_PC_IU);
+		if (!msc_network->iu.sccp)
+			return -EINVAL;
+	}
+#else
+	/* No Iu support, just open up an A instance */
+	msc_network->a.sccp = sccp_setup(ctx, cs7_instance_a, "OsmoMSC-A", DEFAULT_PC_A);
+	if (!msc_network->a.sccp)
+		return -EINVAL;
+#endif
+
+	return 0;
+}
+
 int main(int argc, char **argv)
 {
 	int rc;
@@ -349,6 +412,9 @@ int main(int argc, char **argv)
 	/* For --version, vty_init() must be called before handling options */
 	vty_init(&msc_vty_info);
 
+	osmo_ss7_init();
+	osmo_ss7_vty_init_asp(tall_msc_ctx);
+
 	/* Parse options */
 	handle_options(argc, argv);
 
@@ -491,14 +557,19 @@ TODO: we probably want some of the _net_ ctrl commands from bsc_base_ctrl_cmds_i
 		return 7;
 	}
 
-	/* Set up A-Interface */
-	/* TODO: implement A-Interface and remove above legacy stuff. */
+	if (ss7_setup(tall_msc_ctx)) {
+		printf("Setting up SCCP client failed.\n");
+		return 8;
+	}
 
 #ifdef BUILD_IU
 	/* Set up IuCS */
-	iu_init(tall_msc_ctx, "127.0.0.1", 14001, rcvmsg_iu_cs, rx_iu_event);
+	iu_init(tall_msc_ctx, msc_network->iu.sccp, rcvmsg_iu_cs, rx_iu_event);
 #endif
 
+	/* Set up A interface */
+	a_init(msc_network->a.sccp, msc_network);
+
 	if (msc_cmdline_config.daemonize) {
 		rc = osmo_daemonize();
 		if (rc < 0) {