[asterisk-bugs] [Asterisk 0011474]: Asterisk hangup calls if two identical invites are received

[noreply at bugs.digium.com]

A NOTE has been added to this issue. 
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http://bugs.digium.com/view.php?id=11474 
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Reported By:                drencrom
Assigned To:                
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Project:                    Asterisk
Issue ID:                   11474
Category:                   Channels/chan_sip/Interoperability
Reproducibility:            always
Severity:                   major
Priority:                   normal
Status:                     feedback
Asterisk Version:            1.2.24  
SVN Branch (only for SVN checkouts, not tarball releases): N/A  
SVN Revision (number only!):  
Disclaimer on File?:        N/A 
Request Review:              
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Date Submitted:             12-05-2007 08:06 CST
Last Modified:              12-06-2007 13:50 CST
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Summary:                    Asterisk hangup calls if two identical invites are
received
Description: 
Context: 
Asterisk server receiving incoming SIP calls from a PortaSIP softswitch

Problem:
Sometimes the softswitch sends two identical INVITES in a row as if the
first OK from Asterisk was lost. When this happens Asterisk keeps resending
the 200 OK message although it in fact receives the PortaSIP ACKs and the
debug shows that it supposedly stopped retransmitting the 200 OK packet.
Then, after 6 retransmissions of the OK packet (all of them ACK'd by the
remote party) Asterisk hangs up a perfectly valid and working call.
The call works fine if there is no retransmission of the first INVITE
packet.

Debug:
I'll attach two log files with verbose and debug enabled. Also SIP debug
was active. One of them shows a valid call and the other shows the problem
I described above.
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---------------------------------------------------------------------- 
 drencrom - 12-06-07 13:50  
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FYI: I needed this working in asterisk 1.2 so I did a quick patch to solve
this. What I saw was that the second Invite starts a new thread to send OK
messages and the ACK only stops one of them.
I changed the behaviour so that the second invite only sends one OK
(transmits not reliably) so that there is only one thread to stop.
I don't know if this also happens in Asterisk 1.4 but I don't have time to
test it now. 

Issue History 
Date Modified   Username       Field                    Change               
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12-06-07 13:50  drencrom       Note Added: 0074938                          
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