git:5.2:82635674: core: skip to-tag when computing via branch for invite, ack and cancel - sr-dev

1 Aug 2019

Module: kamailio
Branch: 5.2
Commit: 82635674517b6c96678289ca4e807ae73020eefc
URL: https://github.com/kamailio/kamailio/commit/82635674517b6c96678289ca4e807ae7...
Author: Daniel-Constantin Mierla miconda@gmail.com
Committer: Henning Westerholt hw@skalatan.de
Date: 2019-08-01T09:39:36+02:00
core: skip to-tag when computing via branch for invite, ack and cancel
- proper functionality for stateless proxy in case of negative ACK (in
this case the INVITE has no To-tag, but ACK has it and resulted in
different via branch, making downstream proxy to not match transaction)
(cherry picked from commit b4e11cb25d848651406e0ad355d54f10db971761)
---
Modified: src/core/char_msg_val.h
---
Diff:  https://github.com/kamailio/kamailio/commit/82635674517b6c96678289ca4e807ae7...
Patch: https://github.com/kamailio/kamailio/commit/82635674517b6c96678289ca4e807ae7...
---

diff --git a/src/core/char_msg_val.h b/src/core/char_msg_val.h
index 79461cd836..436f58b401 100644
--- a/src/core/char_msg_val.h
+++ b/src/core/char_msg_val.h
@@ -38,6 +38,7 @@
 inline static int char_msg_val( struct sip_msg *msg, char *cv )
 {
    str src[8];
+	str sempty = str_init("");
if (unlikely(!check_transaction_quadruple(msg))) {
    	LM_ERR("can't calculate char_value due to a parsing error\n");
@@ -55,7 +56,12 @@ inline static int char_msg_val( struct sip_msg *msg, char *cv )
    }
    /* use only the from & to tags */
    src[0]=get_from(msg)->tag_value;
-	src[1]=get_to(msg)->tag_value;
+	if(msg->first_line.u.request.method_value
+			& (METHOD_INVITE|METHOD_ACK|METHOD_CANCEL)) {
+		src[1]=sempty;
+	} else {
+		src[1]=get_to(msg)->tag_value;
+	}
    src[2]= msg->callid->body;
    src[3]= msg->first_line.u.request.uri;
    src[4]= get_cseq( msg )->number;

    