[asterisk-bugs] [Asterisk 0012963]: [patch] chan_iax2 will create multiple sessions when receiving retransmitted NEW

[noreply at bugs.digium.com]

A NOTE has been added to this issue. 
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http://bugs.digium.com/view.php?id=12963 
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Reported By:                jpgrayson
Assigned To:                
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Project:                    Asterisk
Issue ID:                   12963
Category:                   Channels/chan_iax2
Reproducibility:            always
Severity:                   major
Priority:                   normal
Status:                     new
Asterisk Version:           1.4.21 
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:             06-30-2008 18:48 CDT
Last Modified:              06-30-2008 18:55 CDT
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Summary:                    [patch] chan_iax2 will create multiple sessions when
receiving retransmitted NEW
Description: 
When a client initiates a call with a NEW frame, frequently the client will
send a retransmitted NEW frame prior to receiving the ACCEPT frame from
asterisk. This may result in asterisk receiving duplicate NEW frames from
the same client in short succession.

As of at least 1.4.20, asterisk will ACCEPT and create new call sessions
for both of these NEW frames originating from the same client. This results
in much protocol confusion between asterisk and the client and ultimately
leads to asterisk and/or the client terminating the call.

The correct behavior would be for asterisk to recognize second (and third
and fourth) NEW frames from the same source (socket and callno) and ignore
them.

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---------------------------------------------------------------------- 
 jpgrayson - 06-30-08 18:55  
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Attached patch chan_iax2_dup_new_fix.patch.

This implements fix (1). It also cleans up the messy logic using ternary
operators in socket_process() and match().

I believe this is sufficient to fix the problem. Unfortunately this is
socket_process() so second and third opinions are welcome. 

Issue History 
Date Modified   Username       Field                    Change               
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06-30-08 18:55  jpgrayson      Note Added: 0089448                          
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