From: Michel Lespinasse <walken@zoy.org>
To: netdev@vger.kernel.org
Subject: transparent UDP proxy
Date: Tue, 18 Mar 2008 04:59:45 -0700 [thread overview]
Message-ID: <20080318115945.GC11087@zoy.org> (raw)
Hi,
After redirecting UDP connections to a local port with netfilter (DNAT),
I'm trying to figure out what the original intended destination was.
For TCP sockets, I could just use the SO_ORIGINAL_DST socket option,
but that does not work with UDP (I tried, with a 2.6.22.19 kernel)
I also tried using recvmsg and looking for an IP_PKTINFO control message
as outlined in
http://lists.cistron.nl/pipermail/freeradius-users/2002-March/005600.html
but that did not work either (no anciliary data was ever received).
Is there any way to figure out the original destination IP of a NATed
UDP packet ?
Thanks,
--
Michel Lespinasse
reply other threads:[~2008-03-18 12:34 UTC|newest]
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