[Serusers] LCR Backport Example For ser-0.9

[Zeus Ng]

How about something like this.

With the initial INVITE,

... Route processing ...
 if (caller is natted) {
    subst('/From:(.*)<(.*)>(.*)/From:\1<\2>;nat=yes\3/');
 }

 call nathelper or mediaproxy

 t_on_reply(nat reply route);
 t_relay();


In your reply route,

 if (callee is natted) {
    subst('/From:(.*)<(.*)>(.*)/From:\1<\2>;nat=yes\3/');
    call nathelper or mediaproxy
    ... Other processing ...


In your loose route,

 if (loose_route()) {
    if (method=="INVITE") {
      if (search("my_ser_detect_nat=yes") || (sdp in private address  )) {
        call nathelper or mediaproxy
      }
    }
    on reply route
    t_relay()
 }


This does work for me most of the time. However, there are odd situation
that this does not work.

Zeus

> -----Original Message-----
> From: Java Rockx [mailto:javarockx at gmail.com] 
> Sent: Wednesday, 16 March 2005 12:01 PM
> To: Zeus Ng
> Cc: serusers at lists.iptel.org
> Subject: Re: [Serusers] LCR Backport Example For ser-0.9
> 
> 
> OK, but there are two sides of the conversation to test here for NAT.
> 
> Should nat_uac_test("8") be used in a reply_route or 
> something? (Actually this won't work because the re-INIVITE 
> would need to have the c= field in the SDP rewritten if the 
> destination is NATed).
> 
> Anyhow, I mean if the original INVITE is from a NATed client, 
> then I can use client_nat_test() but on the destination side, 
> I still need to know if RTP proxying is needed.
> 
> How do I do this?
> 
> Regards,
> Paul
> 
> 
> On Wed, 16 Mar 2005 11:19:50 +1100, Zeus Ng 
> <zeus.ng at isquare.com.au> wrote:
> > You won't be able to do lookup most of the time with 
> re-INVITE if it 
> > falls into loose_route as the R-URI may have changed to 
> > sip:user at dest.ip.address. (The same applies to case without loose 
> > route as well)
> > 
> > With nathelper, you can do nat_uac_test("8") to test for private 
> > address in the SDP part and do rtpproxy according. Don't think 
> > mediaproxy has this test.
> > 
> > 
> > > -----Original Message-----
> > > From: serusers-bounces at lists.iptel.org 
> [mailto:serusers-bounces at lists.iptel.org] 
> > > On Behalf Of Java Rockx
> > > Sent: Wednesday, 16 March 2005 9:03 AM
> > > To: serusers at lists.iptel.org; Juha Heinanen
> > > Subject: Re: [Serusers] LCR Backport Example For ser-0.9
> > >
> > >
> > > Ahhh, I found my mistake, but can someone verify my thought 
> > > process??
> > >
> > > I'm using mediaproxy and I only proxy RTP streams if the 
> caller or 
> > > the callee are behind a NAT device.
> > >
> > > So during a re-INVITE, I cannot just t_relay() the 
> message because 
> > > the RTP streams will end up at unreachable IP addresses if either 
> > > SIP UA is NATed.
> > >
> > > I can use client_nat_test("3") to test the caller's NAT settings, 
> > > and for the callee I have to use lookup("location") and test my 
> > > nat_flag setting.
> > >
> > > But do I need to call revert_uri() after lookup("location") when 
> > > processing re-INVITEs???
> > >
> > > Regards,
> > > Paul
> > >
> > >
> > > On Tue, 15 Mar 2005 16:17:38 -0500, Java Rockx 
> <javarockx at gmail.com> 
> > > wrote:
> > > > Yep. I agree.
> > > >
> > > > But does this mean for **any** SIP message that
> > > loose_route() returns
> > > > TRUE, I simply call t_relay() and then stop processing 
> via a break 
> > > > command?
> > > >
> > > > I can't remember, but I thought I ran in to some cases
> > > where even when
> > > > loose_route() returned TRUE, I still had to do some other
> > > processing.
> > > >
> > > > Regards,
> > > > Paul
> > > >
> > > >
> > > > On Tue, 15 Mar 2005 20:13:40 +0200, Juha Heinanen 
> <jh at tutpro.com>
> > > > wrote:
> > > > > Java Rockx writes:
> > > > >
> > > > >  > I thought I had mine right, but then I realized that some 
> > > > > re-INVITE  > messages were not being handled properly and
> > > calls were
> > > > > being  > disconnected.
> > > > >
> > > > > you should not use or need to use lcr modules functions for 
> > > > > re-invites. re-invites are in-dialog requests that 
> are forwarded 
> > > > > based on route headers.
> > > > >
> > > > > -- juha
> > > > >
> > > >
> > >
> > > _______________________________________________
> > > Serusers mailing list
> > > serusers at lists.iptel.org http://lists.iptel.org/mailman/listinfo/serusers
> > >
> > 
> >
>