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From: "Lukas Hubschmid (s)" <lukas.hubschmid@students.fhnw.ch>
To: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Cc: netfilter@vger.kernel.org
Subject: Re: TCP sequence checking
Date: Wed, 3 Jun 2015 19:52:21 +0200	[thread overview]
Message-ID: <556F3ED5.6000205@students.fhnw.ch> (raw)
In-Reply-To: <alpine.DEB.2.10.1506031915590.23917@blackhole.kfki.hu>

Thank you Jozsef!
I am not quite sure if I read the C-code correctly - so TCP sequence 
checking seems to be enabled by default, right? Or do I need to set some 
flag when adding a rule?

KR,
Lukas

Am 03.06.2015 um 19:16 schrieb Jozsef Kadlecsik:
> On Wed, 3 Jun 2015, Lukas Hubschmid (s) wrote:
>
>> Does iptables support TCP sequence checking, to check if a TCP packet has a
>> valid sequence number (according to previous packets of the same TCP
>> connection)?
> Yes, have a look at net/netfilter/nf_conntrack_proto_tcp.c in the kernel
> source tree.
>
> Best regards,
> Jozsef
> -
> E-mail  : kadlec@blackhole.kfki.hu, kadlecsik.jozsef@wigner.mta.hu
> PGP key : http://www.kfki.hu/~kadlec/pgp_public_key.txt
> Address : Wigner Research Centre for Physics, Hungarian Academy of Sciences
>            H-1525 Budapest 114, POB. 49, Hungary


  reply	other threads:[~2015-06-03 17:52 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-06-03 13:18 TCP sequence checking Lukas Hubschmid (s)
2015-06-03 17:16 ` Jozsef Kadlecsik
2015-06-03 17:52   ` Lukas Hubschmid (s) [this message]
2015-06-03 19:00     ` Jozsef Kadlecsik

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