RE: Iptables can't close port 25 and 110
-----Original Message-----
From: "Ronald Laarman" <ronald@laarman.xs4all.nl>
To: <debian-firewall@lists.debian.org>
Cc: <R.DElia@starcomitalia.com>
Date: Mon, 26 Jan 2004 13:53:00 +0100
Subject: RE: Iptables can't close port 25 and 110
> I know the difference between 'rejecting' and 'dropping' packages but
> how come iptables -P INPUT DROP will close of port 80.
iptables cannot close any port. You can only make another box believe
that port closed. This is done sending the same rst packet that a closed
port sends.
So you a remote attacker must see the rst packet; otherwise it'll know
you have firewalled an open port.
Drop is not the correct answer: try reject...
Radel
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