relaxed CANCEL matching (no to-tags included) introduced

modules/tm/README

@@ -285,8 +285,8 @@ or cat test/transaction.fifo > /tmp/ser_fifo
 
 Defines
 -------
-- TOTAG enables matching of acknowledgemnts including to-tags;
-  it is disabled by default for two reasons:
+- ACK_TAG enables stricter matching of acknowledgemnts including to-tags;
+  without it, to-tags are ignored; it is disabled by default for two reasons:
   a) it eliminates an unlikely race condition in which
      transaction's to-tag is being rewritten by a 200 OK
      whereas an ACK is being looked up by to-tag
@@ -296,7 +296,13 @@ Defines
   negative reply sent upstream and 200/ACKs are not matched
   as they consititute another transaction. It will make no
   difference at all when the new magic cookie matching is
-  enabled.
+  enabled anyway.
+- CANCEL_TAG similarly enables strict matching of CANCELs 
+  including to-tags -- act of mercy to UACs, who screw up
+  the to-tags (however, it still depends on how forgiving
+  the downstream UAS is); like with ACK_TAG, all this
+  complex transactions matching goes with RFC3261's
+  magic cookie away anyway
 
 
 

modules/tm/t_lookup.c

@@ -191,7 +191,10 @@ int t_lookup_request( struct sip_msg* p_msg , int leave_new_locked )
 			/* To only the uri and ... */
 			if (get_to(t_msg)->uri.len!=get_to(p_msg)->uri.len)
 				continue;
-#ifdef TOTAG
+			/* don't care about to-tags -- many UAC screw them
+			 * up anyway, and it doesn't hurt if we ignore 
+			 * them */
+#ifdef ACKTAG
 			/* ... its to-tag compared to reply's tag */
 			if (p_cell->uas.to_tag.len!=get_to(p_msg)->tag_value.len)
 				continue;
@@ -207,7 +210,7 @@ int t_lookup_request( struct sip_msg* p_msg , int leave_new_locked )
 			if (!EQ_STR(from)) continue;
 			if (memcmp(get_to(t_msg)->uri.s, get_to(p_msg)->uri.s,
 				get_to(t_msg)->uri.len)!=0) continue;
-#ifdef TOTAG
+#ifdef ACKTAG
 			if (
 #ifdef _BUG
 				p_cell->uas.to_tag.len!=0 /* to-tags empty */ || 
@@ -299,8 +302,17 @@ struct cell* t_lookupOriginalT(  struct sip_msg* p_msg )
 			continue;
 		if (!EQ_LEN(from))
 			continue;
+#ifdef CANCEL_TAG
 		if (!EQ_LEN(to))
 			continue;
+#else
+		/* relaxed matching -- we don't care about to-tags anymore,
+		 * many broken UACs screw them up and ignoring them does not
+		 * actually hurt
+		 */
+		if (get_to(t_msg)->uri.len!=get_to(p_msg)->uri.len)
+			continue;
+#endif
 		if (!EQ_REQ_URI_LEN)
 			continue;
 		if (!EQ_VIA_LEN(via1))
@@ -314,8 +326,14 @@ struct cell* t_lookupOriginalT(  struct sip_msg* p_msg )
 			continue;
 		if (!EQ_STR(from))
 			continue;
+#ifdef CANCEL_TAG
 		if (!EQ_STR(to))
 			continue;
+#else
+		if (memcmp(get_to(t_msg)->uri.s, get_to(p_msg)->uri.s,
+					get_to(t_msg)->uri.len)!=0)
+			continue;
+#endif
 		if (!EQ_REQ_URI_STR)
 			continue;
 		if (!EQ_VIA_STR(via1))