Re: [Ekiga-list] Symmetric NAT problem

[Karel Kulhavy <clock twibright com>]

On Mon, Feb 19, 2007 at 04:23:49PM +0000, Paulo J. Matos wrote:
> On 10/11/06, Paulo J. Matos <pocm soton ac uk> wrote:
> > On 10/10/06, Damien Sandras <dsandras seconix com> wrote:
> > > Perhaps, but I'm not confident into SIP over HTTP ...
> >
> > wengophone worked effortlessly. Thanks! It's unfortunate that ekiga
> > doesn't work in my case since I've always been fond of Damien and
> > Ekiga community.
> >
> 
> After some months... here's a recap for reviving this thread.
> 
> I've tried wengo behind my firewall but unfortunately audio/video
> reception is very verrry poor which makes it unusable. So the current
> solution is one I truly hate but the only one: skype for audio, buggy
> kopete msn camera for video. Skype is usable sometimes... kopete is
> nearly usable.

Skype is allegedly vulnerable to remote shell by one malicious UDP packet. They
are allegedly reading x from the packets, doing malloc(x*4), not checking for
arithmetic overflow and then writing into the data. The exploit method is
described in
http://blackhat.com/presentations/bh-europe-06/bh-eu-06-biondi/bh-eu-06-biondi-up.pdf,
page 104-112.

After seeing this I applied a special security patch on skype, but that was in
a very special format suitable for obfuscated black box binary applications, so
had to be administered by the "rm" program instead of the "patch" program.

Ekiga reports a symmetric NAT for me too. I called our sysadmin and asked for
ports 5000-5200 to be mapped to my machine. After that, Ekiga works just fine.
I tried xten xlite before and after and it doesn't work with the Ekiga account.
Sends an invalid (internal) IP address in the SDP exchange so then it doesn't
get the RTP data.

CL<
> 
> My real question is if ekiga will support or already does sip through
> http or whatever technology skype uses to allow me to do calls. If no
> support is on the wishlist, why not? Is it impossible to do? Not
> practical? Not a desirable feature?
> 
> Cheers,
> 
> Paulo Matos
> 
> 
> 
> 
> > Cheers,
> >
> > Paulo Matos
> >
> > > --
> > >  _      Damien Sandras
> > > (o-
> > > //\     Ekiga Softphone: http://www.ekiga.org/
> > > v_/_    FOSDEM 2006    : http://www.fosdem.org/
> > >         SIP Phone      : sip:dsandras ekiga net
> > >                          sip:600000 ekiga net
> > >
> > > _______________________________________________
> > > ekiga-list mailing list
> > > ekiga-list gnome org
> > > http://mail.gnome.org/mailman/listinfo/ekiga-list
> > >
> >
> >
> > --
> > Paulo Jorge Matos - pocm at soton.ac.uk
> > http://www.personal.soton.ac.uk/pocm
> > PhD Student @ ECS
> > University of Southampton, UK
> >
> 
> 
> -- 
> Paulo Jorge Matos - pocm at soton.ac.uk
> http://www.personal.soton.ac.uk/pocm
> PhD Student @ ECS
> University of Southampton, UK
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