[Asterisk-Dev] Contact-header illegally modified in response to REGISTER

[Olle E. Johansson]

Björn Grönesjö wrote:

> Greetings Asterisk developers,
> 
> I have reasons to believe that Asterisk's sip-stack is modifying the
> "Contact:"-header in a response to a REGISTER message in an illegal way.
> 
> RFC 3261; 10.3 Page 66
>       8. The registrar returns a 200 (OK) response.  The response MUST
>          contain Contact header field values enumerating all current
>          bindings.  Each Contact value MUST feature an "expires"
>          parameter indicating its expiration interval chosen by the
>          registrar.  The response SHOULD include a Date header field.
> 
> Asterisk replaced the Contact header field value with the address of 
> record instead of all current bindings as it should.
As stated a number of times on this list:
* We only accept ONE current binding per SIP account. (Asterisk is not
   a forking proxy).
* And yes, we rewrite the Contact header field, not with AOR but with
   something that isn't illegal (The text above doesn't say anything about
   not resolving the domain part) but breaks a lot of implementations.

The Contact: problem has earlier been shown in Snom devices and some
middle-boxes, like the Ingate IX66. I've got a trial patch working in
chan_sip2 (check bugs.digium.com) but need more confirmations that this
patch really solves a problem and not cause new problems. If possible,
test that SIP channel and confirm to me if it works or not.

/Olle