<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=us-ascii">
<style type="text/css" style="display:none;"> P {margin-top:0;margin-bottom:0;} </style>
</head>
<body dir="ltr">
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
Hi Daniel,</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<br>
</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
Thanks for your reply.</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<br>
</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
Used the following script for testing:</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<br>
</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<span>if (is_method("BYE")) {<br>
</span>
<div><br>
</div>
<div> xlog("CALLID: $ci\n");<br>
</div>
<div> xlog("CSEQ: $cs\n");<br>
</div>
<div><br>
</div>
<div> if (t_cancel_callid("$ci", "$cs", "0")) {<br>
</div>
<div> xlog("Transaction cancelled\n");<br>
</div>
<div> } else {<br>
</div>
<div> xlog("Failed to cancel transaction\n");<br>
</div>
<div> }<br>
</div>
<div> send_reply("200", "OK");<br>
</div>
<div> exit;<br>
</div>
<div>}<br>
</div>
<span></span><br>
</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
No cancel message was triggered.</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<br>
</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
Best Regards,</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
Lars</div>
<div id="appendonsend"></div>
<hr style="display:inline-block;width:98%" tabindex="-1">
<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>From:</b> Daniel-Constantin Mierla <miconda@gmail.com><br>
<b>Sent:</b> Friday, October 25, 2019 12:32 PM<br>
<b>To:</b> Kamailio (SER) - Users Mailing List <sr-users@lists.kamailio.org>; Lars Olsson <lars.olsson@optimobile.se><br>
<b>Subject:</b> Re: [SR-Users] Rewrite BYE to Cancel</font>
<div> </div>
</div>
<div style="background-color:#FFFFFF">
<p>Hello,</p>
<p><br>
</p>
<p>actually sending BYE for an in-progress call setup (initial INVITE routed, but 200ok was not received yet) is valid from SIP RFC point of view. So it is not really a broken implementation (or, not to put all my money in, it can be, but not because of this
kind of BYE).</p>
<p><br>
</p>
<p>Practically the BYE can be used to terminate a specific branch in a call setup. Think about parallel forking, and many branches start sending back 183. The caller UA can send BYE to some of the branches and let the others wait to complete.</p>
<p><br>
</p>
<p>The CANCEL has to be used when all the branches should be terminated. If there is a single branch, then the BYE terminates the call in progress, I am not sure what the callee UA should reply to the INVITE.</p>
<p><br>
</p>
<p>On the other hand, in the very few cases when I saw UAs sending BYE for early call setup, the other side was rejecting it, expecting the cancel.</p>
<p><br>
</p>
<p>I expect it should work with kamailio to send 200ok for such BYE and then use t_cancel_callid():</p>
<p><br>
</p>
<p><a href="https://www.kamailio.org/docs/modules/stable/modules/tmx.html#tmx.f.t_cancel_callid">https://www.kamailio.org/docs/modules/stable/modules/tmx.html#tmx.f.t_cancel_callid</a></p>
<p><br>
</p>
<div class="x_moz-cite-prefix">The call-id and cseq values should be the same in the BYE request.</div>
<div class="x_moz-cite-prefix"><br>
</div>
<div class="x_moz-cite-prefix">Try it and write back if works, I am quite curious about...<br>
</div>
<div class="x_moz-cite-prefix"><br>
</div>
<div class="x_moz-cite-prefix">Cheers,<br>
Daniel</div>
<div class="x_moz-cite-prefix"><br>
</div>
<div class="x_moz-cite-prefix">On 25.10.19 12:17, Lars Olsson wrote:<br>
</div>
<blockquote type="cite"><style type="text/css" style="display:none">
<!--
p
{margin-top:0;
margin-bottom:0}
-->
</style>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt; color:rgb(0,0,0)">
Yes it is a BROKEN behavior from the remote system, unfortunately it can not be changed.</div>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt; color:rgb(0,0,0)">
<span style="color:rgb(0,0,0); font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt">Besides this issue, the remote system works as it should.</span><br>
</div>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt; color:rgb(0,0,0)">
<span style="color:rgb(0,0,0); font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt"><br>
</span></div>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt; color:rgb(0,0,0)">
<span style="color:rgb(0,0,0); font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt">A custom b2bua can for sure resolve this, but perhaps not in a standard way.</span></div>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt; color:rgb(0,0,0)">
<span style="color:rgb(0,0,0); font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt">Question is if it is possible to resolve with Kamailio or if I need to patch SEMS to handle this.</span></div>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt; color:rgb(0,0,0)">
<span style="color:rgb(0,0,0); font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt"><br>
</span></div>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt; color:rgb(0,0,0)">
Something like this:</div>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt; color:rgb(0,0,0)">
<br>
</div>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt; color:rgb(0,0,0)">
if ("BYE" && dialog not confirmed)</div>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt; color:rgb(0,0,0)">
reply back 200 OK</div>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt; color:rgb(0,0,0)">
cancel other side of dialog</div>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt; color:rgb(0,0,0)">
<br>
</div>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt; color:rgb(0,0,0)">
As Kamailio can terminate active dialog with sending bye in both directions, I thought that it might be possible to resolve this as well. <span style="color:rgb(0,0,0); font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt">Hence asking for ideas.</span></div>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt; color:rgb(0,0,0)">
<br>
</div>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt; color:rgb(0,0,0)">
Best Regards,</div>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt; color:rgb(0,0,0)">
Lars</div>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt; color:rgb(0,0,0)">
<br>
</div>
<hr tabindex="-1" style="display:inline-block; width:98%">
<div id="x_divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" color="#000000" style="font-size:11pt"><b>From:</b> sr-users
<a class="x_moz-txt-link-rfc2396E" href="mailto:sr-users-bounces@lists.kamailio.org">
<sr-users-bounces@lists.kamailio.org></a> on behalf of Steve Davies <a class="x_moz-txt-link-rfc2396E" href="mailto:steve-lists-srusers@connection-telecom.com">
<steve-lists-srusers@connection-telecom.com></a><br>
<b>Sent:</b> Friday, October 25, 2019 11:25 AM<br>
<b>To:</b> Kamailio (SER) - Users Mailing List <a class="x_moz-txt-link-rfc2396E" href="mailto:sr-users@lists.kamailio.org">
<sr-users@lists.kamailio.org></a><br>
<b>Subject:</b> Re: [SR-Users] Rewrite BYE to Cancel</font>
<div> </div>
</div>
<div>
<div dir="ltr">Hi,
<div><br>
</div>
<div>I'm normally a bystander. But on this occasion I've got to comment - there are broken SIP implementations, and there are BROKEN ones. Surely there is no hope with this one? If they can't get this right just imagine how many more problems it will have.</div>
<div><br>
</div>
<div>Steve</div>
<div><br>
</div>
</div>
<br>
<div class="x_x_gmail_quote">
<div dir="ltr" class="x_x_gmail_attr">On Fri, 25 Oct 2019 at 11:19, Lars Olsson <<a href="mailto:lars.olsson@optimobile.se">lars.olsson@optimobile.se</a>> wrote:<br>
</div>
<blockquote class="x_x_gmail_quote" style="margin:0px 0px 0px
0.8ex; border-left:1px solid rgb(204,204,204); padding-left:1ex">
<div dir="ltr">
<div style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt; color:rgb(0,0,0)">
hi,</div>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt; color:rgb(0,0,0)">
<br>
</div>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt; color:rgb(0,0,0)">
I have a Kamailio setup infront of a SIP system that do not handle cancellation of a INVITE correctly.</div>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt; color:rgb(0,0,0)">
The system sends out a BYE request instead of a Cancel request on non connected dialogs.</div>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt; color:rgb(0,0,0)">
<br>
</div>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt; color:rgb(0,0,0)">
I am trying to find a way to let Kamailio "translate" the BYE request to a Cancel reqeust for the ongoing INVITE dialog.</div>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt; color:rgb(0,0,0)">
<br>
</div>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt; color:rgb(0,0,0)">
Alternative if SEMS b2bua can do it, but currently it replies: "not sip-relaying BYE in not connected dlg", and I have not found any obvious way to rewrite it there.</div>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt; color:rgb(0,0,0)">
<br>
</div>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt; color:rgb(0,0,0)">
Any thoughts. I can not change the behavior of the remote system.</div>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt; color:rgb(0,0,0)">
<br>
</div>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt; color:rgb(0,0,0)">
Best Regards,</div>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt; color:rgb(0,0,0)">
Lars</div>
</div>
_______________________________________________<br>
Kamailio (SER) - Users Mailing List<br>
<a href="mailto:sr-users@lists.kamailio.org" target="_blank">sr-users@lists.kamailio.org</a><br>
<a href="https://lists.kamailio.org/cgi-bin/mailman/listinfo/sr-users" rel="noreferrer" target="_blank">https://lists.kamailio.org/cgi-bin/mailman/listinfo/sr-users</a><br>
</blockquote>
</div>
</div>
<br>
<fieldset class="x_mimeAttachmentHeader"></fieldset>
<pre class="x_moz-quote-pre">_______________________________________________
Kamailio (SER) - Users Mailing List
<a class="x_moz-txt-link-abbreviated" href="mailto:sr-users@lists.kamailio.org">sr-users@lists.kamailio.org</a>
<a class="x_moz-txt-link-freetext" href="https://lists.kamailio.org/cgi-bin/mailman/listinfo/sr-users">https://lists.kamailio.org/cgi-bin/mailman/listinfo/sr-users</a>
</pre>
</blockquote>
<pre class="x_moz-signature" cols="72">--
Daniel-Constantin Mierla -- <a class="x_moz-txt-link-abbreviated" href="http://www.asipto.com">www.asipto.com</a>
<a class="x_moz-txt-link-abbreviated" href="http://www.twitter.com/miconda">www.twitter.com/miconda</a> -- <a class="x_moz-txt-link-abbreviated" href="http://www.linkedin.com/in/miconda">www.linkedin.com/in/miconda</a>
Kamailio Advanced Training, Oct 21-23, 2019, Berlin, Germany -- <a class="x_moz-txt-link-freetext" href="https://asipto.com/u/kat">https://asipto.com/u/kat</a></pre>
</div>
</body>
</html>