bsc: Handle wildcard endpoint name in MGCP CRCX

MGCP permits for the CallAgent to send a wildcarded endpoint name,
at which point the MGW itself must allocate an endpoint name and
return it as SpecificEndpointId parameter in the CRCX response.

Change-Id: I704bbe4e11b27e83a6ae6a71aa6a715dc8301f34

bsc/MSC_ConnectionHandler.ttcn

@@ -75,7 +75,7 @@ function f_MediaState_init(inout MediaState g_media, integer nr, HostName bts, H
 		peer := -
 	}
 
-	//g_media.mgcp_ep := int2str(i) & "@mgw";
+	g_media.mgcp_ep := "rtpbridge/" & int2str(nr) & "@mgw";
 
 	for (var integer i:= 0; i < sizeof(g_media.mgcp_conn); i := i+1) {
 		g_media.mgcp_conn[i].mime_type := "AMR";
@@ -169,6 +169,16 @@ altstep as_Media() runs on MSC_ConnHdlr {
 	[] MGCP.receive(tr_CRCX) -> value mgcp_cmd {
 		var SDP_Message sdp;
 		var integer cid := f_get_free_mgcp_conn();
+		if (match(mgcp_cmd.line.ep, t_MGCP_EP_wildcard)) {
+			if (cid != 0) {
+				setverdict(fail, "MGCP wildcard EP only works in first CRCX");
+				self.stop;
+			}
+			/* we keep the endpoint name allocated during MediaState_init */
+		} else {
+			/* Call Agent allocated endpoint, trust/use it always */
+			g_media.mgcp_ep := mgcp_cmd.line.ep;
+		}
 		if (isvalue(mgcp_cmd.sdp)) {
 			sdp := mgcp_cmd.sdp;
 			g_media.mgcp_conn[cid].peer.host := sdp.connection.conn_addr.addr;
@@ -181,7 +191,10 @@ altstep as_Media() runs on MSC_ConnHdlr {
 							mgcp_conn.mime_type & "/" &
 							int2str(mgcp_conn.sample_rate))),
 				valueof(ts_SDP_ptime(mgcp_conn.ptime)) } ));
-		MGCP.send(ts_CRCX_ACK(mgcp_cmd.line.trans_id, mgcp_conn.conn_id, sdp));
+		var template MgcpResponse mgcp_resp;
+		mgcp_resp := ts_CRCX_ACK(mgcp_cmd.line.trans_id, mgcp_conn.conn_id, sdp);
+		f_mgcp_par_append(mgcp_resp.params, ts_MgcpParSpecEP(g_media.mgcp_ep));
+		MGCP.send(mgcp_resp);
 		g_media.mgcp_conn[cid].crcx_seen := true;
 		repeat;
 		}

library/MGCP_Emulation.ttcn

@@ -208,8 +208,12 @@ function f_mgcp_ep(MgcpMessage msg) return MgcpEndpoint {
 	if (ischosen(msg.command)) {
 		return msg.command.line.ep;
 	} else {
-		/* FIXME */
-		return "null@none";
+		var MgcpEndpoint ep;
+		if (f_mgcp_find_param(msg, "Z", ep) == false) {
+			setverdict(fail, "No SpecificEndpointName in MGCP response", msg);
+			self.stop;
+		}
+		return ep;
 	}
 }
 
@@ -273,7 +277,8 @@ function main(MGCPOps ops, MGCP_conn_parameters p, charstring id) runs on MGCP_E
 				} else {
 					if (cmd.line.verb == "CRCX") {
 						vc_conn := ops.create_cb.apply(cmd, id);
-						if (true /* non-wildcard EP */) {
+						if (not match(cmd.line.ep, t_MGCP_EP_wildcard)) {
+							/* non-wildcard EP, use directly */
 							f_ep_table_add(vc_conn, cmd.line.ep);
 						} else {
 							/* add this transaction to list of pending transactions */

library/MGCP_Templates.ttcn

@@ -34,6 +34,12 @@ module MGCP_Templates {
 		val := hex2str(rid)
 	};
 
+	/* 3.2.1.3 SpecificEndpointId */
+	template MgcpParameter ts_MgcpParSpecEP(MgcpEndpoint ep) := {
+		code := "Z",
+		val := ep
+	};
+
 	/* 3.2.2.10: LocalConnectionOptions (codec, packetization, bandwidth, ToS, eco, gain, silence, ...) */
 	template MgcpParameter t_MgcpParLocConnOpt(template charstring lco) := { "L", lco };
 
@@ -326,5 +332,25 @@ module MGCP_Templates {
 		sdp := *
 	}
 
+	function f_mgcp_find_param(MgcpMessage msg, MgcpInfoCode code, out charstring ret)
+	return boolean {
+		var MgcpParameterList pars;
+		if (ischosen(msg.command)) {
+			pars := msg.command.params;
+		} else {
+			pars := msg.response.params;
+		}
+		for (var integer i := 0; i < sizeof(pars); i := i+1) {
+			if (pars[i].code == code) {
+				ret := pars[i].val;
+				return true;
+			}
+		}
+		return false;
+	}
+
+	/* template to determine if a MGCP endpoint is a wildcard endpoint */
+	template charstring t_MGCP_EP_wildcard := (pattern "\*@*", pattern "rtpbridge/\*@*");
+
 
 }