Expose the real ports (src/dst) used by TC-based write op

As src/dst ports may be ephemeral, expose (via holders in socket_info struct) the real used ports during the last write operation

Related to #1692

(cherry picked from commit 9dde6d5)

modules/proto_bin/proto_bin.c

@@ -556,6 +556,9 @@ static int proto_bin_send(struct socket_info* send_sock,
 			if (n==0) {
 				/* mark the ID of the used connection (tracing purposes) */
 				last_outgoing_tcp_id = c->id;
+				send_sock->last_local_real_port = c->rcv.dst_port;
+				send_sock->last_remote_real_port = c->rcv.src_port;
+
 				/* connect is still in progress, break the sending
 				 * flow now (the actual write will be done when 
 				 * connect will be completed */
@@ -594,6 +597,8 @@ static int proto_bin_send(struct socket_info* send_sock,
 
 			/* mark the ID of the used connection (tracing purposes) */
 			last_outgoing_tcp_id = c->id;
+			send_sock->last_local_real_port = c->rcv.dst_port;
+			send_sock->last_remote_real_port = c->rcv.src_port;
 
 			/* we successfully added our write chunk - success */
 			tcp_conn_release(c, 0);
@@ -631,6 +636,8 @@ static int proto_bin_send(struct socket_info* send_sock,
 
 	/* mark the ID of the used connection (tracing purposes) */
 	last_outgoing_tcp_id = c->id;
+	send_sock->last_local_real_port = c->rcv.dst_port;
+	send_sock->last_remote_real_port = c->rcv.src_port;
 
 	tcp_conn_release(c, (n<len)?1:0/*pending data in async mode?*/ );
 	return n;

modules/proto_hep/proto_hep.c

@@ -727,6 +727,8 @@ static int hep_tcp_send (struct socket_info* send_sock,
 			if (n==0) {
 				/* mark the ID of the used connection (tracing purposes) */
 				last_outgoing_tcp_id = c->id;
+				send_sock->last_local_real_port = c->rcv.dst_port;
+				send_sock->last_remote_real_port = c->rcv.src_port;
 				/* connect is still in progress, break the sending
 				 * flow now (the actual write will be done when
 				 * connect will be completed */
@@ -766,6 +768,8 @@ static int hep_tcp_send (struct socket_info* send_sock,
 
 			/* mark the ID of the used connection (tracing purposes) */
 			last_outgoing_tcp_id = c->id;
+			send_sock->last_local_real_port = c->rcv.dst_port;
+			send_sock->last_remote_real_port = c->rcv.src_port;
 
 			/* we successfully added our write chunk - success */
 			tcp_conn_release(c, 0);
@@ -803,6 +807,8 @@ static int hep_tcp_send (struct socket_info* send_sock,
 
 	/* mark the ID of the used connection (tracing purposes) */
 	last_outgoing_tcp_id = c->id;
+	send_sock->last_local_real_port = c->rcv.dst_port;
+	send_sock->last_remote_real_port = c->rcv.src_port;
 
 	tcp_conn_release(c, (n<len)?1:0/*pending data in async mode?*/ );
 

modules/proto_tls/proto_tls.c

@@ -494,6 +494,8 @@ static int proto_tls_send(struct socket_info* send_sock,
 
 	/* mark the ID of the used connection (tracing purposes) */
 	last_outgoing_tcp_id = c->id;
+	send_sock->last_local_real_port = c->rcv.dst_port;
+	send_sock->last_remote_real_port = c->rcv.src_port;
 
 	tcp_conn_release(c, 0);
 	return n;

modules/proto_ws/proto_ws.c

@@ -487,6 +487,8 @@ static int proto_ws_send(struct socket_info* send_sock,
 
 	/* mark the ID of the used connection (tracing purposes) */
 	last_outgoing_tcp_id = c->id;
+	send_sock->last_local_real_port = c->rcv.dst_port;
+	send_sock->last_remote_real_port = c->rcv.src_port;
 
 	tcp_conn_release(c, 0);
 	return n;

modules/proto_wss/proto_wss.c

@@ -520,6 +520,8 @@ static int proto_wss_send(struct socket_info* send_sock,
 
 	/* mark the ID of the used connection (tracing purposes) */
 	last_outgoing_tcp_id = c->id;
+	send_sock->last_local_real_port = c->rcv.dst_port;
+	send_sock->last_remote_real_port = c->rcv.src_port;
 
 	tcp_conn_release(c, 0);
 	return n;

net/proto_tcp/proto_tcp.c

@@ -793,7 +793,8 @@ static int proto_tcp_send(struct socket_info* send_sock,
 			LM_ERR("Unknown destination - cannot open new tcp connection\n");
 			return -1;
 		}
-		LM_DBG("no open tcp connection found, opening new one, async = %d\n",tcp_async);
+		LM_DBG("no open tcp connection found, opening new one, async = %d\n",
+			tcp_async);
 		/* create tcp connection */
 		if (tcp_async) {
 			n = tcpconn_async_connect(send_sock, to, buf, len, &c, &fd);
@@ -807,23 +808,24 @@ static int proto_tcp_send(struct socket_info* send_sock,
 				ip_addr2a( &c->rcv.src_ip ), c->rcv.src_port,
 				ip_addr2a( &c->rcv.dst_ip ), c->rcv.dst_port );
 
-
-
 			if (n==0) {
 				/* trace the message */
 				if ( TRACE_ON( c->flags ) &&
 						check_trace_route( trace_filter_route_id, c) ) {
 					if ( tcpconn2su( c, &src_su, &dst_su) < 0 ) {
 						LM_ERR("can't create su structures for tracing!\n");
 					} else {
-						trace_message_atonce( PROTO_TCP, c->cid, &src_su, &dst_su,
+						trace_message_atonce( PROTO_TCP, c->cid,
+							&src_su, &dst_su,
 							TRANS_TRACE_CONNECT_START, TRANS_TRACE_SUCCESS,
 							&AS_CONNECT_INIT, t_dst );
 					}
 				}
 
 				/* mark the ID of the used connection (tracing purposes) */
 				last_outgoing_tcp_id = c->id;
+				send_sock->last_local_real_port = c->rcv.dst_port;
+				send_sock->last_remote_real_port = c->rcv.src_port;
 
 				/* connect is still in progress, break the sending
 				 * flow now (the actual write will be done when
@@ -912,6 +914,8 @@ static int proto_tcp_send(struct socket_info* send_sock,
 
 			/* mark the ID of the used connection (tracing purposes) */
 			last_outgoing_tcp_id = c->id;
+			send_sock->last_local_real_port = c->rcv.dst_port;
+			send_sock->last_remote_real_port = c->rcv.src_port;
 
 			/* we successfully added our write chunk - success */
 			sh_log(c->hist, TCP_SEND2MAIN, "send 3, (%d)", c->refcnt);
@@ -958,6 +962,8 @@ static int proto_tcp_send(struct socket_info* send_sock,
 
 	/* mark the ID of the used connection (tracing purposes) */
 	last_outgoing_tcp_id = c->id;
+	send_sock->last_local_real_port = c->rcv.dst_port;
+	send_sock->last_remote_real_port = c->rcv.src_port;
 
 	sh_log(c->hist, TCP_SEND2MAIN, "send 6, (%d, async: %d)", c->refcnt, n < len);
 	tcp_conn_release(c, (n<len)?1:0/*pending data in async mode?*/ );

socket_info.h

@@ -54,6 +54,16 @@ struct socket_info {
 	struct ip_addr adv_address; /* Advertised address in ip_addr form (for find_si) */
 	unsigned short adv_port;    /* optimization for grep_sock_info() */
 	unsigned short children;
+	/* these are IP-level local/remote ports used during the last write op via
+	 * this sock (or a connection belonging to this sock). These values are 
+	 * optional (populated only by the TCP-based protocol, for ephemeral ports.
+	 * Note: they are populate ONLY by a write op and they are not ever reset,
+	 * they are simply overwritten by the next write op on this socket/conn.
+	 * IMPORTANT: when reading them, be sure you are just after a write ops,
+	 * otherwise you may read old data here */
+	unsigned short last_local_real_port;
+	unsigned short last_remote_real_port;
+
 	struct socket_info* next;
 	struct socket_info* prev;
 };