Fix NULL to_uri due to b2b_msg_get_to is called after accessing to_ur…

…i in case of adv_ct is not set, so contact uri can not be parsed if advertise_contact is not provided

(cherry picked from commit 33bf277)

modules/b2b_logic/bridging.c

@@ -2182,6 +2182,13 @@ int b2bl_bridge_msg(struct sip_msg* msg, str* key, int entity_no, str *adv_ct)
 
 	b2b_api.apply_lumps(msg);
 
+	if (b2b_msg_get_from(msg, &from_uri, &from_dname)< 0 ||
+	b2b_msg_get_to(msg, &to_uri, b2bl_htable[hash_index].flags)< 0)
+	{
+		LM_ERR("Failed to get to or from from the message\n");
+		goto error;
+	}
+
 	if (!adv_ct) {
 		memset(&ct_uri, 0, sizeof(struct sip_uri));
 		if (contact_user && parse_uri(to_uri.s, to_uri.len, &ct_uri) < 0) {
@@ -2227,12 +2234,6 @@ int b2bl_bridge_msg(struct sip_msg* msg, str* key, int entity_no, str *adv_ct)
 	LM_DBG("Contact: %.*s\n", contact.len, contact.s);
 
 	/* create server entity from Invite */
-	if (b2b_msg_get_from(msg, &from_uri, &from_dname)< 0 ||
-	b2b_msg_get_to(msg, &to_uri, b2bl_htable[hash_index].flags)< 0)
-	{
-		LM_ERR("Failed to get to or from from the message\n");
-		goto error;
-	}
 	server_id = b2b_api.server_new(msg, adv_ct ? adv_ct : &local_contact,
 			b2b_server_notify, &b2bl_mod_name, tuple->key,
 			get_tracer(tuple), NULL, NULL);