[core] run post processing callbacks only on SIP traffic

Credits go to @lemenkov
Alternative to #2316

(cherry picked from commit eee990d)

forward.h

@@ -114,7 +114,7 @@ static inline int msg_send( struct socket_info* send_sock, int proto,
 	/* the raw processing callbacks are free to change whatever inside
 	 * the buffer further use out_buff.s and at the end try to free out_buff.s
 	 * if changed by callbacks */
-	if (proto != PROTO_BIN)
+	if ( is_sip_proto(proto) )
 		run_post_raw_processing_cb(POST_RAW_PROCESSING,&out_buff, msg);
 
 	/* update the length for further processing */

ip_addr.h

@@ -166,6 +166,9 @@ struct socket_id {
 /* check if a socket_info is marked as anycast */
 #define is_anycast(_si) (_si->flags & SI_IS_ANYCAST)
 
+/* checks if the given protocol is a SIP one (versus HEP, BIN, SMPP, etc) 
+ * we rely here on the fact at all the SIP protos are in a sequance */
+#define is_sip_proto(_proto) (PROTO_UDP<=(_proto) && (_proto)<=PROTO_WSS)
 
 struct net* mk_net(struct ip_addr* ip, struct ip_addr* mask);
 struct net* mk_net_bitlen(struct ip_addr* ip, unsigned int bitlen);