[asterisk-bugs] [Asterisk 0017347]: Astersik generates responses with missing Via headers

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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https://issues.asterisk.org/view.php?id=17347 
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Reported By:                klaus3000
Assigned To:                
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Project:                    Asterisk
Issue ID:                   17347
Category:                   Channels/chan_sip/Interoperability
Reproducibility:            always
Severity:                   minor
Priority:                   normal
Status:                     new
Asterisk Version:           1.6.2.7 
JIRA:                        
Regression:                 No 
Reviewboard Link:            
SVN Branch (only for SVN checkouts, not tarball releases): N/A 
SVN Revision (number only!):  
Request Review:              
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Date Submitted:             2010-05-17 08:07 CDT
Last Modified:              2010-05-17 11:42 CDT
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Summary:                    Astersik generates responses with missing Via
headers
Description: 
If Asterisk detects a spiraled SIP call (outgoing INVITE is coming in
again), it will handle the forwarding internally (Local/...) and cancels
the outgoing call. Therefore Asterisk will send a CANCEL and due to
spiraling it will also receive a CANCEL and will respond with 487 to the
incoming spiraled INVITE.

This 487 response generated by Asterisk is malformed, it misses the second
Via header (which is present in the incoming INVITE, and in the 100 Trying
sent by Asterisk immediately after receiving the spiraled INVITE). 

Problem happens with both, pedantic=yes and =no.

I tried to capture the call with "call show history" but for some reasons,
this call is not present in the history.
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 (0122001) klaus3000 (reporter) - 2010-05-17 11:42
 https://issues.asterisk.org/view.php?id=17347#c122001 
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Scenario: Asterisk performs an outgoing call to a peer. The call
is spiraled back to Asterisk. Asterisk handles the forward
internally (Dial creates a Local channel in the peer's context).

Message 8 is malformed as it misses a Via header.

PSTN            Asterisk                   Proxy
 --SETUP---------->
                   1 ----------INVITE--------> >--\
                   2 <---------100------------    | spiral
                   3 <---INVITE--------------- <--/
                   4 ----100----------------->

                   5 ----------CANCEL--------> >--\
                   6 <---------200(CANCEL)----    | spiral
                   7 <---CANCEL--------------- <--/
                   8 ----487(INVITE)--------->
                   9 ----200(CANCEL)--------->

Find the ngrep dump captured at the proxy in ngrep.txt.

Find Asterisk's logging in full.log. 

Issue History 
Date Modified    Username       Field                    Change               
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2010-05-17 11:42 klaus3000      Note Added: 0122001                          
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