[Kamailio-Devel] [SR-Dev] content length

[Daniel-Constantin Mierla]

Hello,

On 03/30/2009 05:24 PM, Andrei Pelinescu-Onciul wrote:
> On Mar 30, 2009 at 16:06, Daniel-Constantin Mierla <miconda at gmail.com> wrote:
>   
>> Hello,
>>
>> the data lumps system is critically affected if content-length is wrong 
>> for UDP. The anchor_lump() calls abort() in the case content-length is 
>> higher than actually body length.
>>     
>
> It's true that anchor_lump() calls abort if the offset passed to it is
> outside the message, but I don't see where anchor_lump() is called with
> a value depending on Content-Length (at least in sip-router and ser).
>   
I haven't checked the modules in ser, just the data_lump.c file for 
anchor_lump() in sip-router core. In k most of the modules takes the 
length from header. Probably a wrapper that corrects it would be good.

The issue remains, is this a case of runtime abort()?

>   
>> This can be prevented by called sanity 
>> module to check the content length, however, I consider being too 
>> drastic to have abort in such case, it would be better to return an 
>> error and let the sip router process other messages. Opinions?
>>
>> Checking sip-router sources, it faces same issue.
>>
>> Another option would be to correct the C-L value locally, but the right 
>> one is that phone vendor fixes its side.
>>     
>
> It's fixed automatically in sip-router, if the destination protocol is
> tcp or tls.
>   
Others reaction was to 400-reply the request, being a basic bug that 
should be fixed in uac side...

Cheers,
Daniel

-- 
Daniel-Constantin Mierla
SIP Router Masterclass - Kamailio (OpenSER) Training
http://www.asipto.com/index.php/sip-router-masterclass/