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Date: Fri, 30 May 2014 10:58:14 -0700
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Subject: Re: kern/190102: [tcp] net.inet.tcp.drop_synfin=1 no longer works on
 FreeBSD 10+ [regression]
From: hiren panchasara <hiren.panchasara@gmail.com>
To: Eygene Ryabinkin <rea@freebsd.org>
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- bugs (as this is not related to it)

On Wed, May 28, 2014 at 10:46 PM, Eygene Ryabinkin <rea@freebsd.org> wrote:

> clearing FIN bit for SYN packets was
> the standard behaviour of pf since approximately at least 10 years,
>   http://svnweb.freebsd.org/base/vendor-sys/pf/dist/sys/contrib/pf/net/pf_norm.c?view=markup&pathrev=126258#l1242

I am curious, what's the rationale for this behavior? Why does PF
clear the FIN bit for such a packet being a firewall?

Cheers,
Hiren