Re: [Kamailio-Users] UAC on ACK in reInvite - sr-users

26 Nov 2008

To finish the thread: I just entered below loose_route():
if (check_route_param("vsf=")) {
  avp_write("$hdr(Route[0])", "$avp(rr-param)");
  avp_subst("$avp(rr-param)", "/^.*?(;vsf=[^>]+).*/\1/");  #
$hdr(Route[0]) is not 1st header only, if multi header in one line
  xlog("L_INFO", ">> Stored UAC params $avp(rr-param)");

  add_rr_param("$avp(rr-param)");
} 

...
  -----Original Message-----
 From: Schober Walter 
 Sent: Wednesday, November 26, 2008 2:39 PM
 To: 'Klaus Darilion'
 Cc: &#39;users(a)lists.kamailio.org&#39;
 Subject: RE: AW: [Kamailio-Users] UAC on ACK in reInvite

 See below...

  -----Original Message-----
 From: Klaus Darilion [mailto:klaus.mailinglists@pernau.at] 
 Sent: Wednesday, November 26, 2008 1:21 AM  [...]

 This is clearly a bug in the useragent. The route set must not be 
 changed with reINVITEs. Thus, according to the standard the 
 Record-Route 
 headers for indialog requests are not needed. Maybe you are calling 
 record_route() for indialog requests and this confuses the client.  Fully agree on
this. But some proxies add Record-Route, some 
 don't, Openser/Kamailio can configure it.

 It's not that clear in the RFC, but I see it the same way:
 RFC 3261, 12.2 Request within a Dialog
 ...
    Requests within a dialog MAY contain Record-Route and 
 Contact header
    fields.  However, these requests do not cause the dialog's 
 route set
    to be modified, although they may modify the remote target URI.

 12.2.1.2 Processing the Responses
 -> The only thing mentioned is that the _Target URI_ gets 
 refreshed by the 200 OK. 

 => reInvites do not modify the routeset of any subsequent 
 request, neither the ACK not any other upcoming request.

  Try removing the record_route() for indialog
requests - may   then the 
  buggy client remembers the original route set.
 Done. Client sends ACK on reInvite directly then :-( 
 Counterpath is OK, Teles Voipbox not, other clients to be tested ...

 So I will have to add vsf uri param from Route to record 
 route in the proxy. This at least is a reason to upgrade :-) 
 It's done more easily with tranformations.

 Thanks for the discussion! For me it's "clearly a bug in the 
 UA" now, too ;-) However, let's find a workaround.

 br
 Walter 