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From: Jan Humme <jan.humme@xs4all.nl>
To: "christophe barbé" <christophe.barbe.ml@online.fr>
Cc: netfilter@lists.samba.org
Subject: Re: simple rules and unexpected traffic
Date: Fri, 5 Jul 2002 00:54:36 +0200	[thread overview]
Message-ID: <02070500543604.06327@Lms> (raw)
In-Reply-To: <20020704224523.GB909@localhost>

On Friday 05 July 2002 00:45, christophe barbé wrote:
> On Fri, Jul 05, 2002 at 08:35:53AM +1000, George Vieira wrote:
> > Yes I've found that some user space programs can see stuff before
> > iptables.. tcpdump too I think...
>
> Yes it sounds logical for tcpdump or tools like that (which pass the
> interface in promiscuisious mode) to see everything. I was not expecting
> the same from a unprivileged app like gkrellm.
> It is stil unclear for me what is the data processing path.
>
> Has someone a clear picture of the packets path ?

It is no problem to open a socket and receive a copy of all raw packets 
before they get to the kernel iptables modules. See "man 7 packet" for 
details.

I believe this is how tcpdump does it too.

Jan Humme.


  reply	other threads:[~2002-07-04 22:54 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2002-07-04 22:35 simple rules and unexpected traffic George Vieira
2002-07-04 22:45 ` christophe barbé
2002-07-04 22:54   ` Jan Humme [this message]
2002-07-04 22:57     ` christophe barbé
  -- strict thread matches above, loose matches on Subject: below --
2002-07-04 23:54 George Vieira
2002-07-05  0:34 ` christophe barbé
2002-07-04 23:44 George Vieira
2002-07-04 23:47 ` christophe barbé
2002-07-04 14:10 christophe barbé
2002-07-04 21:01 ` christophe barbé

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