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From: "Miguel Alejandro González" <maggonzz@gmail.com>
To: netfilter-devel@vger.kernel.org
Subject: about ip header options
Date: Wed, 7 Nov 2012 16:38:54 -0600	[thread overview]
Message-ID: <CAOSBYzf3VCAeKybJee6CFrB+PjQWesOHjxsJ6a7dpoC_CSxxVQ@mail.gmail.com> (raw)

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Hello

I have a netfilter module on the mangle table PREROUTING... I want to
validate unexpired routes in ipv4 headers, but I think the TCP/IP
stack already does this... because it is mentioned on the rfc 1812 so
I'm guessing it is already implemented by the kernel

but somehow my module catches the packet first before the kernel does
its magic...

As I understand the picture I'm attaching represents the whole process
the TCP/IP stack performs to handle the options in a IPv4 packet, but
I still don't understand how netfilter works with the stack

Do I have to process the packet's options in my module or what?

Please, help

Regards

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             reply	other threads:[~2012-11-07 22:38 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-11-07 22:38 Miguel Alejandro González [this message]
2012-11-08 12:42 ` about ip header options Pablo Neira Ayuso

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