From mboxrd@z Thu Jan  1 00:00:00 1970
From: <hamals@infinito.it>
Subject: bad tcp packets
Date: Tue, 23 Nov 2004 13:18:25 +0100
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Cc: franco.riggi@tiscali.it


Hello to everyone

I'm reading "Iptables Tutorial 1.1.19" by Oskar 
Andreasoon, and I cant understand these bad packets rules


$IPTABLES -N bad_tcp_packets
#
#
# bad_tcp_packets chain
#
$IPTABLES -A bad_tcp_packets -p tcp --tcp-flags SYN,ACK 
SYN,ACK \
-m state --state NEW -j REJECT --reject-with tcp-reset
$IPTABLES -A bad_tcp_packets -p tcp ! --syn -m state 
--state NEW -j LOG \
--log-prefix "New not syn:"
$IPTABLES -A bad_tcp_packets -p tcp ! --syn -m state 
--state NEW -j DROP

someone could explain me why that are bad tcp packets?

Thanks

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