mgcp: Allocate a different port for the networking...

Use the right source port when sending the message.
diff --git a/openbsc/src/mgcp/mgcp_vty.c b/openbsc/src/mgcp/mgcp_vty.c
index ea10a2e..fe73c7a 100644
--- a/openbsc/src/mgcp/mgcp_vty.c
+++ b/openbsc/src/mgcp/mgcp_vty.c
@@ -57,6 +57,7 @@
 	vty_out(vty, "  bind ip %s%s", g_cfg->source_addr, VTY_NEWLINE);
 	vty_out(vty, "  bind port %u%s", g_cfg->source_port, VTY_NEWLINE);
 	vty_out(vty, "  rtp bts-base %u%s", g_cfg->rtp_bts_base_port, VTY_NEWLINE);
+	vty_out(vty, "  rtp net-base %u%s", g_cfg->rtp_net_base_port, VTY_NEWLINE);
 	vty_out(vty, "  rtp ip-dscp %d%s", g_cfg->endp_dscp, VTY_NEWLINE);
 	if (g_cfg->audio_payload != -1)
 		vty_out(vty, "  sdp audio payload number %d%s", g_cfg->audio_payload, VTY_NEWLINE);
@@ -163,6 +164,16 @@
 	return CMD_SUCCESS;
 }
 
+DEFUN(cfg_mgcp_rtp_net_base_port,
+      cfg_mgcp_rtp_net_base_port_cmd,
+      "rtp net-base <0-65534>",
+      "Base port to use for network port\n" "Port\n")
+{
+	unsigned int port = atoi(argv[0]);
+	g_cfg->rtp_net_base_port = port;
+	return CMD_SUCCESS;
+}
+
 ALIAS_DEPRECATED(cfg_mgcp_rtp_bts_base_port, cfg_mgcp_rtp_base_port_cmd,
       "rtp base <0-65534>", "Base port to use")
 
@@ -277,6 +288,7 @@
 	install_element(MGCP_NODE, &cfg_mgcp_bind_early_cmd);
 	install_element(MGCP_NODE, &cfg_mgcp_rtp_base_port_cmd);
 	install_element(MGCP_NODE, &cfg_mgcp_rtp_bts_base_port_cmd);
+	install_element(MGCP_NODE, &cfg_mgcp_rtp_net_base_port_cmd);
 	install_element(MGCP_NODE, &cfg_mgcp_rtp_ip_dscp_cmd);
 	install_element(MGCP_NODE, &cfg_mgcp_rtp_ip_tos_cmd);
 	install_element(MGCP_NODE, &cfg_mgcp_sdp_payload_number_cmd);
@@ -322,6 +334,12 @@
 			LOGP(DMGCP, LOGL_FATAL, "Failed to bind: %d\n", rtp_port);
 			return -1;
 		}
+
+		rtp_port = rtp_calculate_port(ENDPOINT_NUMBER(endp), g_cfg->rtp_net_base_port);
+		if (mgcp_bind_net_rtp_port(endp, rtp_port) != 0) {
+			LOGP(DMGCP, LOGL_FATAL, "Failed to bind: %d\n", rtp_port);
+			return -1;
+		}
 	}
 
 	return 0;