[asterisk-bugs] [Asterisk 0015262]: [patch] RFC3261 Via-header branches not done right (section

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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https://issues.asterisk.org/view.php?id=15262 
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Reported By:                maniax
Assigned To:                dvossel
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Project:                    Asterisk
Issue ID:                   15262
Category:                   Channels/chan_sip/General
Reproducibility:            sometimes
Severity:                   major
Priority:                   normal
Status:                     closed
Asterisk Version:           Older 1.4 
Regression:                 No 
SVN Branch (only for SVN checkouts, not tarball releases): N/A 
SVN Revision (number only!):  
Request Review:              
Resolution:                 fixed
Fixed in Version:           
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Date Submitted:             2009-06-03 09:51 CDT
Last Modified:              2009-09-18 11:23 CDT
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Summary:                    [patch] RFC3261 Via-header branches not done right
(section
Description: 
We're testing asterisk and res_fax against a Zoiper Communicator and got
into a SIP issue. When there's a re-INVITE to T.38, the branch parameter is
the same as for the INVITE, which in fact is wrong, because:

RFC 3261, https://issues.asterisk.org/view.php?id=8.1.1.7 : "...the branch ID
was constructed in the fashion
described by this specification (that is, globally unique)."
https://issues.asterisk.org/view.php?id=17.2.3: "
The branch parameter in the topmost Via header field of the request
is examined.  If it is present and begins with the magic cookie
"z9hG4bK", the request was generated by a client transaction
compliant to this specification.  Therefore, the branch parameter
will be unique across all transactions sent by that client.
"

Attached is a packet capture that shows this - the re-invite is not
accepted by the softphone as it has the same branch parameter and is
treated as a retransmit.
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---------------------------------------------------------------------- 
 (0111000) svnbot (reporter) - 2009-09-18 11:23
 https://issues.asterisk.org/view.php?id=15262#c111000 
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Repository: asterisk
Revision: 219452

_U  branches/1.6.2/
U   branches/1.6.2/channels/chan_sip.c

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r219452 | dvossel | 2009-09-18 11:23:21 -0500 (Fri, 18 Sep 2009) | 27
lines

Merged revisions 219451 via svnmerge from 
https://origsvn.digium.com/svn/asterisk/trunk

................
  r219451 | dvossel | 2009-09-18 11:20:41 -0500 (Fri, 18 Sep 2009) | 20
lines
  
  Merged revisions 219450 via svnmerge from 
  https://origsvn.digium.com/svn/asterisk/branches/1.4
  
  ........
    r219450 | dvossel | 2009-09-18 11:19:15 -0500 (Fri, 18 Sep 2009) | 14
lines
    
    via-header branches not updated correctly on INVITE
    
    INVITE requests must always contain a new unique branch id. When
    a new branch id is created for an INVITE, the dialog's invite_branch
    variable must be updated so CANCEL requests use the correct branch id.
    
    (closes issue https://issues.asterisk.org/view.php?id=15262)
    Reported by: maniax
    Patches:
          asterisk-1.6.1.0-sip-branch.patch uploaded by tweety (license
608)
          invite_new_branch_trunk.diff uploaded by dvossel (license 671)
    Tested by: maniax, dvossel
  ........
................

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http://svn.digium.com/view/asterisk?view=rev&revision=219452 

Issue History 
Date Modified    Username       Field                    Change               
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2009-09-18 11:23 svnbot         Checkin                                      
2009-09-18 11:23 svnbot         Note Added: 0111000                          
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