osmo-bsc: improve checking of sccp addresses

Use the check functionality of libosmo-sigtran to test if the
sccp addresses are smantically correct.

3 files changed, 31 insertions, 12 deletions

diff --git a/openbsc/include/openbsc/bsc_msc_data.h b/openbsc/include/openbsc/bsc_msc_data.h
index 6d5ed9d5c..1ffe2a9c5 100644
--- a/openbsc/include/openbsc/bsc_msc_data.h
+++ b/openbsc/include/openbsc/bsc_msc_data.h
@@ -115,6 +115,7 @@ struct bsc_msc_data {
 	/* Sigtran connection data */
 	struct {
 		uint32_t cs7_instance;
+		bool cs7_instance_valid;
 		struct osmo_sccp_instance *sccp;
 		struct osmo_sccp_user *sccp_user;
 
diff --git a/openbsc/src/osmo-bsc/osmo_bsc_sigtran.c b/openbsc/src/osmo-bsc/osmo_bsc_sigtran.c
index 705a87fed..3d8aecd6f 100644
--- a/openbsc/src/osmo-bsc/osmo_bsc_sigtran.c
+++ b/openbsc/src/osmo-bsc/osmo_bsc_sigtran.c
@@ -410,16 +410,6 @@ static void osmo_bsc_sigtran_reset_cb(const void *priv)
 	osmo_bsc_sigtran_tx_reset(msc);
 }
 
-/* Check if a given sccp address fulfills minimum requirements */
-static int test_addr(const struct osmo_sccp_addr *addr)
-{
-	if (!(addr->presence & OSMO_SCCP_ADDR_T_SSN))
-		return -EINVAL;
-	if (!(addr->presence & OSMO_SCCP_ADDR_T_PC))
-		return -EINVAL;
-
-	return 0;
-}
 
 /* Initalize osmo sigtran backhaul */
 int osmo_bsc_sigtran_init(struct llist_head *mscs)
@@ -439,14 +429,20 @@ int osmo_bsc_sigtran_init(struct llist_head *mscs)
 		LOGP(DMSC, LOGL_NOTICE, "Initializing SCCP connection to MSC %s (%s)\n",
 		     osmo_sccp_addr_dump(&msc->a.msc_addr), msc_name);
 
+		/* Check if the VTY could determine a valid CS7 instance */
+		if (msc->a.cs7_instance_valid == false) {
+			LOGP(DMSC, LOGL_ERROR, "A-interface: Invalid CS7 instance\n");
+			return -EINVAL;
+		}
+
 		/* Check if the sccp-address fullfill minimum requirements (SSN+PC is present) */
-		if (test_addr(&msc->a.bsc_addr) < 0) {
+		if (!osmo_sccp_check_addr(&msc->a.bsc_addr, OSMO_SCCP_ADDR_T_SSN | OSMO_SCCP_ADDR_T_PC)) {
 			LOGP(DMSC, LOGL_ERROR,
 			     "A-interface: invalid local SCCP address (a.bsc_addr=%s)\n",
 			     osmo_sccp_addr_dump(&msc->a.bsc_addr));
 			return -EINVAL;
 		}
-		if (test_addr(&msc->a.msc_addr) < 0) {
+		if (!osmo_sccp_check_addr(&msc->a.msc_addr, OSMO_SCCP_ADDR_T_SSN | OSMO_SCCP_ADDR_T_PC)) {
 			LOGP(DMSC, LOGL_ERROR,
 			     "A-interface: invalid remote SCCP address for the MSC (a.msc_addr=%s)\n",
 			     osmo_sccp_addr_dump(&msc->a.msc_addr));
diff --git a/openbsc/src/osmo-bsc/osmo_bsc_vty.c b/openbsc/src/osmo-bsc/osmo_bsc_vty.c
index d4a87a773..4d94af45e 100644
--- a/openbsc/src/osmo-bsc/osmo_bsc_vty.c
+++ b/openbsc/src/osmo-bsc/osmo_bsc_vty.c
@@ -726,7 +726,18 @@ DEFUN(cfg_msc_cs7_bsc_addr,
 		return CMD_WARNING;
 	}
 
+	/* Prevent mixing addresses from different CS7/SS7 instances */
+	if (msc->a.cs7_instance_valid) {
+		if (msc->a.cs7_instance != ss7->cfg.id) {
+			vty_out(vty,
+				"SCCP address %s from different CS7 instance%s",
+				bsc_addr_name, VTY_NEWLINE);
+			return CMD_WARNING;
+		}
+	}
+
 	msc->a.cs7_instance = ss7->cfg.id;
+	msc->a.cs7_instance_valid = true;
 	enforce_standard_ssn(vty, &msc->a.bsc_addr);
 	return CMD_SUCCESS;
 }
@@ -747,7 +758,18 @@ DEFUN(cfg_msc_cs7_msc_addr,
 		return CMD_WARNING;
 	}
 
+	/* Prevent mixing addresses from different CS7/SS7 instances */
+	if (msc->a.cs7_instance_valid) {
+		if (msc->a.cs7_instance != ss7->cfg.id) {
+			vty_out(vty,
+				"SCCP address %s from different CS7 instance%s",
+				msc_addr_name, VTY_NEWLINE);
+			return CMD_WARNING;
+		}
+	}
+
 	msc->a.cs7_instance = ss7->cfg.id;
+	msc->a.cs7_instance_valid = true;
 	enforce_standard_ssn(vty, &msc->a.msc_addr);
 	return CMD_SUCCESS;
 }