sccp_sap_up_ran: ignore RAN until MSC is connected

Related: SYS#5560
Change-Id: Idf9501412484fa92e8836952609fba7c5443d6c9

include/osmocom/bsc_nat/msc.h

@@ -36,4 +36,6 @@ struct msc *msc_get(void);
 void msc_tx_reset(struct msc *msc);
 void msc_rx_reset_ack(struct msc *msc);
 
+bool msc_is_connected(struct msc *msc);
+
 void msc_free(struct msc *msc);

src/osmo-bsc-nat/bsc_nat_fsm.c

@@ -29,6 +29,7 @@
 #include <osmocom/bsc_nat/bsc_nat_fsm.h>
 #include <osmocom/bsc_nat/bssap.h>
 #include <osmocom/bsc_nat/logging.h>
+#include <osmocom/bsc_nat/msc.h>
 
 #define DEFAULT_PC_RAN "0.23.1" /* same as default for OsmoMSC */
 #define DEFAULT_PC_CN "0.23.3" /* same as default for OsmoBSC */
@@ -208,10 +209,17 @@ static int sccp_sap_up_ran(struct osmo_prim_hdr *oph, void *scu)
 	struct osmo_scu_prim *prim = (struct osmo_scu_prim *) oph;
 	struct osmo_sccp_addr *addr; /* BSC's address */
 	struct osmo_sccp_addr peer_addr_out;
+	struct msc *msc;
 	int rc = -1;
 
 	LOGP(DMAIN, LOGL_DEBUG, "Rx %s from RAN\n", osmo_scu_prim_name(oph));
 
+	msc = msc_get();
+	if (!msc_is_connected(msc)) {
+		LOGP(DMAIN, LOGL_DEBUG, "Ignoring message from RAN, MSC is not connected yet\n");
+		goto error;
+	}
+
 	switch (OSMO_PRIM_HDR(oph)) {
 	case OSMO_PRIM(OSMO_SCU_PRIM_N_CONNECT, PRIM_OP_INDICATION):
 		/* indication of new inbound connection request */

src/osmo-bsc-nat/msc_fsm.c

@@ -152,3 +152,8 @@ void msc_rx_reset_ack(struct msc *msc)
 {
 	osmo_fsm_inst_dispatch(msc->fi, MSC_FSM_EV_RX_RESET_ACK, NULL);
 }
+
+bool msc_is_connected(struct msc *msc)
+{
+	return msc->fi->state == MSC_FSM_ST_CONNECTED;
+}