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From: "Bruno Negrão" <vpopmail@engepel.com.br>
To: netfilter@lists.netfilter.org
Subject: the impossible "iptables -C" option
Date: Fri, 23 Jul 2004 20:24:54 -0300	[thread overview]
Message-ID: <01be01c4710c$440a79e0$5100a8c0@egp> (raw)

Hi guys, I didn't understand the following question and answer on
netfilter's faq:

"3.18 Why isn't the 'iptables -C' (--check) option implemented?

Well, first of all, we're lazy ;). To be honest, implementing a check
option is almost impossible as soon as you start to do stateful
firewalling. Traditional stateless firewalling bases it's decision just on
information present in the packets header. But with connection tracking
(and '-m state' based rules), the outcome of the filtering decision depends
on header+payload, as well as header+payload of previous packets within
this connection."

First of all, what does they mean about "--check"? What would they check?

What is "packet payload"? How does it make the "--check" option impossible
to be implemented?

thanks in advance,
bruno negrao





             reply	other threads:[~2004-07-23 23:24 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2004-07-23 23:24 Bruno Negrão [this message]
2004-07-24  7:56 ` the impossible "iptables -C" option Antony Stone
2004-07-24  8:36   ` Re[2]: " mortar
2004-07-24 10:16   ` Chris Brenton
2004-07-24 10:27     ` Antony Stone
2004-07-24 11:45       ` Chris Brenton
2004-07-24 18:46     ` Les Mikesell
2004-07-24 20:13       ` Antony Stone
2004-07-25 17:50         ` Les Mikesell
2004-07-25 18:08           ` Antony Stone

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