Re: TCP SYN packets which have the FIN flag set.
Hi!
On Friday 05 November 2004 12:27, Baruch Even wrote:
> > iptables -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT
> > iptables -A INPUT -m state --state NEW -p tcp --tcp-flags ALL SYN -j ACCEPT
>
> Please dont do that!
> You can use SYN,ACK,FIN,RST SYN to check for illegal flags.
Shouldn't
iptables -A INPUT -m state --state INVALID -j DROP
as the _first_ rule take care of all packages with illegal flags?
Unfortunately, I haven't found any documentation what exactly is
considered INVALID. Anybody?
Cheers,
Stefan
--
Technische Universitaet Muenchen Raum: 1131
Physik-Department T39 Tel.: 089/289-12197
James-Franck-Strasse E-Mail: sfritsch@ph.tum.de
D-85748 Garching
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