[icq-devel] direct connections behaviour when using a proxy

rad2k rad2k at mail.ru
Fri Jan 3 14:28:18 CET 2003

I've done deeper tests.
Well, the mirabilis client configured to use a proxy does bind its port.
It doesn't directly attend peer 2 peer negotiations.

I tried using the proxy and then issuing a 'connect' to the icq client but
the proxy was filtering any ports but 443 :(. 

I sniffed how two mirabilis clients talked to each other by having the same
proxy in the LAN and what was happening was that the client which initialized
the connection sent the 4,6 server packets for File transfer request THROUGH
the server, hence the other client received the information through the proxy and
once the agreement was finished a peer 2 peer connection was initialized.

Anyway, I guess the best way to do it would be if the proxy allowed any destination
port which I cant test right now :(.

On Wed, 11 Dec 2002 19:38:15 +0100
Mark van Cuijk <webmaster at phedny.zzn.com> wrote:

> Hi,
> Yes, I do understand what's going on. I'll describe one detail a little more.
> Since ICQ is configured to connect throught a proxy server, it will not only use this proxy for connections to the ICQ network, but also for direct connections. Not only 
> outbound (which are functioning actually the same as a connections to the network), but also inbound, in which case it asks the proxy to open a port.
> So actually, it's the proxy which listens for connections and not the ICQ client.
> Take this with a pinch of salt, ICQ might be listening on some port, but it's not expecting you on it, so it refuses to speak to you. It's expecting the connection via the 
> proxy...
> - Mark
> 11-12-2002 18:38:39, <rad2k at mail.ru> wrote:
> >Hmm In case your reply was for my problem..thanks
> >but that isn't my problem, sorry ;)
> >Since i wrote already that both my client and the other client are on the same LAN and the DC is established using the LAN ip's i dont need to worry about using proxy's 
> either socks or not.
> >My problem is still weird, when a mirabilis client on the other side
> >of the LAN has a proxy configured to connect to the icq server, after opening a socket THROUGH THE LAN, the remote mirabilis client will ignore my DC packets.
> >
> >Doesn't matter if you still don't understand wtf is going on since
> >as soon as possible ill continue trying to make this lovely
> >protocol work.
> >
> >t/c
> >
> >/rad2k
> >
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