From mboxrd@z Thu Jan 1 00:00:00 1970 From: Miguel Angel Amador L Subject: Re: bad tcp packets Date: Tue, 23 Nov 2004 09:42:24 -0300 Message-ID: <1101213743.32475.37.camel@JOKER.INFOWORLD.CL> References: Reply-To: amador@puc.cl Mime-Version: 1.0 Content-Transfer-Encoding: quoted-printable Return-path: In-Reply-To: List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: netfilter-bounces@lists.netfilter.org Errors-To: netfilter-bounces@lists.netfilter.org Content-Type: text/plain; charset="iso-8859-1" To: netfilter@lists.netfilter.org El mar, 23-11-2004 a las 09:18, hamals@infinito.it escribi=C3=B3: > Hello to everyone >=20 > I'm reading "Iptables Tutorial 1.1.19" by Oskar=20 > Andreasoon, and I cant understand these bad packets rules >=20 >=20 > $IPTABLES -N bad_tcp_packets > # > # > # bad_tcp_packets chain > # > $IPTABLES -A bad_tcp_packets -p tcp --tcp-flags SYN,ACK=20 > SYN,ACK \ > -m state --state NEW -j REJECT --reject-with tcp-reset May be that you can't got the three flags on, in the same packet > $IPTABLES -A bad_tcp_packets -p tcp ! --syn -m state=20 > --state NEW -j LOG \ > --log-prefix "New not syn:" > $IPTABLES -A bad_tcp_packets -p tcp ! --syn -m state=20 > --state NEW -j DROP May be, if the packet haven't the syn flags on, the packet is not new > someone could explain me why that are bad tcp packets? I don't secure, but i thing that is this. regards Miguel Amador > Thanks >=20 > _______________________________________ > Connessione ed e-mail gratuita da 10 mb > consultabile tramite web e tramite pop. > www.infinito.it vieni a scoprire tutti=20 > i nostri servizi! >=20 > http://www.infinito.it/xmail >=20 >=20