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Date: Fri, 6 Jan 2012 08:42:25 +0100
From: Daniel Hartmeier <daniel@benzedrine.cx>
To: Gerald McNulty <gmnt99@gmail.com>
Message-ID: <20120106074225.GA24312@insomnia.benzedrine.cx>
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Cc: freebsd-pf@freebsd.org
Subject: Re: Basic transparent filtering with pf
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On Fri, Jan 06, 2012 at 02:51:07AM +0000, Gerald McNulty wrote:

> Is this something that requires further pf rules? Or something in the C
> code?

I think you're describing

  http://lists.freebsd.org/pipermail/freebsd-net/2011-March/028225.html

With pf, you could try to reroute the replies to the loopback interface:

  pass out on $ext_if reply-to lo0 inet proto tcp user {uid} keep state

Maybe first start by matching on a specific IP (e.g. 100.100.100.5) instead
of the uid, as a test.

HTH,
Daniel