From: Bill Prochazka <billprozac@gmail.com>
To: netfilter@vger.kernel.org
Subject: NAT table bypass for local traffic
Date: Wed, 28 Apr 2010 13:19:48 -0400 [thread overview]
Message-ID: <n2h812495871004281019nb633c037i7dc04336bc47bd59@mail.gmail.com> (raw)
So, I have an interesting observation. I am doing some wonky fun
stuff with iptables and have noticed that traffic generated by a host
on an existing connection, is bypassing the NAT table for processing.
I ran netcat listenening on a host and log all traffic on the OUTPUT
and POSTROUTING chains. When I connect from another host, the traffic
is not processed by those chains. However, if I initiate a connection
from that host, the chains are processed appropriately. Is this by
design or is this a bug? The traffic does pass through the mangle
table, just not the NAT table. Anyone ever encounter something like
this? I have verified this on both CentOS 5.4 (2.6.18) and busybox
(2.6.27).
Bill
next reply other threads:[~2010-04-28 17:19 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-04-28 17:19 Bill Prochazka [this message]
2010-04-28 17:59 ` NAT table bypass for local traffic Steve Fink
2010-04-28 19:46 ` Jan Engelhardt
2010-04-28 20:50 ` Bill Prochazka
2010-04-28 20:55 ` Sven-Haegar Koch
2010-04-29 6:25 ` ratheesh k
[not found] ` <001636c5c15232dea504855f65c2@google.com>
2010-04-30 6:25 ` ratheesh k
2010-04-30 7:22 ` ratheesh k
2010-05-01 4:23 ` ratheesh k
2010-05-01 14:29 ` Pascal Hambourg
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