[Devel] Patch: nathelper.c session-level c= enhancement

[Bogdan-Andrei Iancu]

Hi Bayan,

I applied on cvs a modified version of our patch (I simplified the 
things a little bit ;) ). This behaviour is by default turned off - if 
you want to enable it, you have to set the "c" flag for 
force_rtp_proxy(). See:
    http://openser.org/docs/modules/1.1.x/nathelper.html#AEN275

regards,
bogdan

Bayan Towfiq wrote:

> This patch makes nathelper change the session-level connection 
> information (c=) line even if there is a c= line in the 
> media-description. This helps some strange UAs interoperating with 
> gateways like Cisco AS5350 and AS5400 where it sends out a 
> session-level c= line and a media-description c= line. It fixes the 
> fact that they take the session-level c= over the media-description 
> one by changing both without any bad effects or breaking RFC compliance.
>
> Here's an example:
> 1.1.1.1 is the media gateway.
> 2.2.2.2 is rtpproxy
>
> Old Behavior:
>
> v=0.
> o=CiscoSystemsSIP-GW-UserAgent 6470 978 IN IP4 1.1.1.1.
> s=SIP Call.
> *c=IN IP4 1.1.1.1.*
> t=0 0.
> m=audio 17266 RTP/AVP 18 101.
> *c=IN IP4 1.1.1.1.*
> a=rtpmap:18 G729/8000.
> a=fmtp:18 annexb=no.
> a=rtpmap:101 telephone-event/8000.
> a=fmtp:101 0-16.
> a=ptime:20.
> v=0.
> -----changes to----
> v=0.
> o=CiscoSystemsSIP-GW-UserAgent 6470 978 IN IP4 1.1.1.1.
> s=SIP Call.
> *c=IN IP4 1.1.1.1.*
> t=0 0.
> m=audio 35080 RTP/AVP 18 101.
> *c=IN IP4 2.2.2.2.*
> a=rtpmap:18 G729/8000.
> a=fmtp:18 annexb=no.
> a=rtpmap:101 telephone-event/8000.
> a=fmtp:101 0-16.
> a=ptime:20.
> a=nortpproxy:yes.
>
> New Behavior
>
> v=0.
> o=CiscoSystemsSIP-GW-UserAgent 6470 978 IN IP4 1.1.1.1.
> s=SIP Call.
> *c=IN IP4 1.1.1.1.*
> t=0 0.
> m=audio 17266 RTP/AVP 18 101.
> *c=IN IP4 1.1.1.1.*
> a=rtpmap:18 G729/8000.
> a=fmtp:18 annexb=no.
> a=rtpmap:101 telephone-event/8000.
> a=fmtp:101 0-16.
> a=ptime:20.
> v=0.
> -----changes to----
> v=0.
> o=CiscoSystemsSIP-GW-UserAgent 6470 978 IN IP4 1.1.1.1.
> s=SIP Call.
> *c=IN IP4 2.2.2.2.*
> t=0 0.
> m=audio 35080 RTP/AVP 18 101.
> *c=IN IP4 2.2.2.2.*
> a=rtpmap:18 G729/8000.
> a=fmtp:18 annexb=no.
> a=rtpmap:101 telephone-event/8000.
> a=fmtp:101 0-16.
> a=ptime:20.
> a=nortpproxy:yes.
>