[sr-dev] LCR: defunct_gw() is dangerous

[Iñaki Baz Castillo]

2011/12/28 Iñaki Baz Castillo <ibc at aliax.net>:
>> i'm lost.  why is your sip proxy forwarding a sip request that is
>> totally (not just one header) malformed? and why is your sip proxy able
>> to forward such a request when your uas is not able to respond to it?
>> any how is this all correct based on rfc3261?
>
> Hi Juha, my SIP proxy is Kamailio 3.2 :)
>
> And why it is forwarding such an invalid request is a good question.
> Please let me get a trace of the malformed request. Tomorrow I will
> paste it here.
>
> Cheers.

Anyhow, it could occur that the request contains a valid SIP header
(token: value) but with an invalid grammar (i.e. a P-Asserted-Identity
with a wrong URI value). The proxy could not check it (because in some
configuration it just ignores such a header) but later the UAS/GW
could inspect it and drop the request since the header is invalid (and
it could reply a 400 or just drop the request).

-- 
Iñaki Baz Castillo
<ibc at aliax.net>