nat: Make the code work in terms of endpoints instead of timeslot/multiplex

We are going to have more than one trunk, so all code hardcoding the
multiplex to zero must go. Avoid this kind of problem by saving the
MGCP endpoint number and comparing that.

2 files changed, 15 insertions, 17 deletions

diff --git a/openbsc/src/nat/bsc_mgcp_utils.c b/openbsc/src/nat/bsc_mgcp_utils.c
index e3258f02f..4983c352c 100644
--- a/openbsc/src/nat/bsc_mgcp_utils.c
+++ b/openbsc/src/nat/bsc_mgcp_utils.c
@@ -45,7 +45,7 @@ int bsc_mgcp_assign(struct sccp_connections *con, struct msgb *msg)
 	uint16_t cic;
 	uint8_t timeslot;
 	uint8_t multiplex;
-	int combined;
+	int endp;
 
 	if (!msg->l3h) {
 		LOGP(DNAT, LOGL_ERROR, "Assignment message should have l3h pointer.\n");
@@ -68,22 +68,22 @@ int bsc_mgcp_assign(struct sccp_connections *con, struct msgb *msg)
 	multiplex = (cic & ~0x1f) >> 5;
 
 
-	combined = (32 * multiplex) + timeslot;
+	endp = mgcp_timeslot_to_endpoint(multiplex, timeslot);
 
 	/* find stale connections using that endpoint */
 	llist_for_each_entry(mcon, &con->bsc->nat->sccp_connections, list_entry) {
-		if (mcon->msc_timeslot == combined) {
+		if (mcon->msc_endp == endp) {
 			LOGP(DNAT, LOGL_ERROR,
-			     "Timeslot %d was assigned to 0x%x and now 0x%x\n",
-			     combined,
+			     "Endpoint %d was assigned to 0x%x and now 0x%x\n",
+			     endp,
 			     sccp_src_ref_to_int(&mcon->patched_ref),
 			     sccp_src_ref_to_int(&con->patched_ref));
 			bsc_mgcp_dlcx(mcon);
 		}
 	}
 
-	con->msc_timeslot = combined;
-	con->bsc_timeslot = con->msc_timeslot;
+	con->msc_endp = endp;
+	con->bsc_endp = endp;
 	return 0;
 }
 
@@ -147,19 +147,17 @@ static void bsc_mgcp_send_dlcx(struct bsc_connection *bsc, int endpoint)
 
 void bsc_mgcp_init(struct sccp_connections *con)
 {
-	con->msc_timeslot = -1;
-	con->bsc_timeslot = -1;
+	con->msc_endp = -1;
+	con->bsc_endp = -1;
 	con->crcx = 0;
 }
 
 void bsc_mgcp_dlcx(struct sccp_connections *con)
 {
 	/* send a DLCX down the stream */
-	if (con->bsc_timeslot != -1 && con->crcx) {
-		int bsc_endp = mgcp_timeslot_to_endpoint(0, con->bsc_timeslot);
-		int msc_endp = mgcp_timeslot_to_endpoint(0, con->msc_timeslot);
-		bsc_mgcp_send_dlcx(con->bsc, bsc_endp);
-		bsc_mgcp_free_endpoint(con->bsc->nat, msc_endp);
+	if (con->bsc_endp != -1 && con->crcx) {
+		bsc_mgcp_send_dlcx(con->bsc, con->bsc_endp);
+		bsc_mgcp_free_endpoint(con->bsc->nat, con->msc_endp);
 	}
 
 	bsc_mgcp_init(con);
@@ -172,9 +170,9 @@ struct sccp_connections *bsc_mgcp_find_con(struct bsc_nat *nat, int endpoint)
 	struct sccp_connections *sccp;
 
 	llist_for_each_entry(sccp, &nat->sccp_connections, list_entry) {
-		if (sccp->msc_timeslot == -1)
+		if (sccp->msc_endp == -1)
 			continue;
-		if (mgcp_timeslot_to_endpoint(0, sccp->msc_timeslot) != endpoint)
+		if (sccp->msc_endp != endpoint)
 			continue;
 
 		con = sccp;
diff --git a/openbsc/src/nat/bsc_nat_vty.c b/openbsc/src/nat/bsc_nat_vty.c
index d8af1c23f..b72eb4e26 100644
--- a/openbsc/src/nat/bsc_nat_vty.c
+++ b/openbsc/src/nat/bsc_nat_vty.c
@@ -121,7 +121,7 @@ DEFUN(show_sccp, show_sccp_cmd, "show sccp connections",
 			sccp_src_ref_to_int(&con->patched_ref),
 			con->has_remote_ref,
 			sccp_src_ref_to_int(&con->remote_ref),
-			con->msc_timeslot, con->bsc_timeslot,
+			con->msc_endp, con->bsc_endp,
 			bsc_con_type_to_string(con->con_type),
 			VTY_NEWLINE);
 	}