[SR-Users] Trouble with 302 Redirect

[Muhammad Zaka]

Hi Alex,

We have a similar issue (slightly complex) as it involves sip parallel forking.

The issue is that failure_route[] occurs when all sip forked are exhausted even though "302 Moved Temporarily" has been responded back by one of the SIP endpoint quite quickly.

So, we wish to handle 302 onreply_route[] as it is received quite promptly but as you pointed out Kamailio doesn’t let us set the contact header or append_to_reply.

Please can you suggest me is there any way out we can change the sip contact when using sip parallel forking.

Many Thanks

Regards
Muhammad Adil M Zaka

-----Original Message-----
From: sr-users <sr-users-bounces at lists.kamailio.org> On Behalf Of Alex Balashov
Sent: 16 January 2020 22:32
To: sr-users at lists.kamailio.org
Subject: Re: [SR-Users] Trouble with 302 Redirect

Try doing this in a failure_route[]; onreply_route[] isn't really meant to transform replies, just to passively observe or drop them.

Also, you'll want to use append_to_reply():

   https://kamailio.org/docs/modules/5.3.x/modules/textops.html#textops.f.append_to_reply

Note that the conditions that give rise to the invocation of a failure_route are broader and somewhat more abstract than any given SIP reply -- e.g. transaction reply timeouts. So, you would want to structure your failure_route like this:

   failure_route[REDIRECT_HANDLE] {
      if(t_is_canceled())
         exit;

      if(t_branch_timeout()) {
         # Handle the timeout case...
	 
	 exit;
      }

      # Use $T_rpl to access reply code ($rs) and reply reason if needed
      # ($rs), per:
      #
      # https://www.kamailio.org/wiki/cookbooks/5.3.x/pseudovariables#t_rpl_pv

      if($T_rpl($rs) == 486) {
         append_to_reply("Contact: <sip:...>\r\n");
         t_reply("302", "Moved Temporarily");
	 exit;
      }

      # Some other case.
   }

-- Alex

On Thu, Jan 16, 2020 at 03:54:54PM -0500, Jim Leahy wrote:

> Hi All,
>    I'm having some issues trying to properly send a '302 Moved Temporarily'
> reply to the calling UAC (UAC1) when the remote UAC (UAC2) returns a 
> 486 status (Do Not Disturb). The goal is to redirect UAC1 to a 
> voicemail server when UAC2 is in DND.
> Here are the pertinent parts of my config:
> 
> route {
>         # drop some things right away
>         route(DROP);
> 
>         # perform sanity check
>         route(SANITYCHECK);
> 
>         # handle registrations
>         if(is_method("REGISTER")) {
>                 route(REGISTRATION);
>                 exit;
>         }
> 
>         # handle invites
>         if(is_method("INVITE")) {
>                 route("INVITE");
>                 exit;
>         }
> 
>         route(RELAY);
> }
> 
> route[INVITE] {
>         # add this proxy to the record-route so it stays in the loop
>         record_route();
> 
>         # if we can find this user in the location DB...
>         if(lookup("location")) {
>                 # relay the invite to the new dURI
>                 t_on_failure("FOURDIGITFAIL");
>                 t_on_reply("FOURDIGITREPLY");
>                 route(RELAY);
>                 # go back to the main route
>                 return;
>         }
> 
> onreply_route[FOURDIGITREPLY] {
>         if(t_check_status("4[0-9]{2}")) {
>                 t_reply("302", "Moved Temporarily");
>         }
> }
> 
> I'm having issues with the t_reply in the onreply_route. It 
> successfully sends the reply, but I can't seem to set the Contact 
> header properly. I'm trying to set it to the location of the user's 
> mailbox on the voicemail sever (ie sip:1000 at vmpbx.domain.com), but nothing I try works. I've tried:
>      remove_hf("Contact");
>      insert_hf("Contact: sip:1000 at vmpbx.domain.com");
>      t_reply("302", "Moved Temporarily");
> 
> But as I understand it, that just changes the header in the reply from 
> UAC2, not the reply I'm sending to UAC1
> 
> Then I tried:
>      append_to_reply("Contact: sip:1000 at vmpbx.domain.com" );
>      t_reply("302", "Moved Temporarily");
> 
> But I can't use append_to_reply in an onreply block.
> How can I change the Contact header in the reply that's sent? Am I 
> just going about this the wrong way? Any help would be appreciated. 
> Thanks

> _______________________________________________
> Kamailio (SER) - Users Mailing List
> sr-users at lists.kamailio.org
> https://lists.kamailio.org/cgi-bin/mailman/listinfo/sr-users


--
Alex Balashov | Principal | Evariste Systems LLC

Tel: +1-706-510-6800 / +1-800-250-5920 (toll-free)
Web: http://www.evaristesys.com/, http://www.csrpswitch.com/

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