[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:              07-02-2008 12:48 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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---------------------------------------------------------------------- 
 Corydon76 - 07-02-08 12:48  
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> > b) Anywhere where you've changed possible semantics, I need to see a
> > comment in the code, just in case the semantics are incorrect. This
will
> > make finding those cases easier in the future.
 
> I really don't know what you want here. Any non-whitespace change has
> the possibility to change semantics. The code says what the semantic
is;
> beyond that comments are for the "why" not the "what". If there are
> specific places you have in mind, I'll do my best to comment them.
 
I'm specifically interested in seeing comments in any place where you've
specifically said that that you are changing how Asterisk is responding. 
So, protocol semantics, specifically.  Something along the lines of
"Asterisk used to allow this, it is now more strict in that it requires
that." 

Issue History 
Date Modified   Username       Field                    Change               
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07-02-08 12:48  Corydon76      Note Added: 0089605                          
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