From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Leonardo Rodrigues ( listas )" <leolistas@solucoesip.net>
Subject: Re: making services invisible
Date: Thu, 10 Oct 2002 11:41:32 -0300
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To: Eric Leblond <eleblond@init-sys.com>, netfilter@lists.netfilter.org


    DROP would make nmap ( or any other scanner ) mark that port as filtered
too. To make services closed and 'invisible' to scanners, you should use '-j
REJECT --reject-with tcp-reset'.

    Sincerily,
    Leonardo Rodrigues

----- Original Message -----
From: "Eric Leblond" <eleblond@init-sys.com>
To: <netfilter@lists.netfilter.org>
Sent: Thursday, October 10, 2002 10:46 AM
Subject: Re: making services invisible


On Thu, 2002-10-10 at 15:13, Julio Cesar Ody wrote:
> Hello. I'm using Slackware 8.1, kernel 2.4.18 and iptables v1.2.7a. I
> blocked external acess to some services using the following rule:
>
> iptables -A INPUT -i ! eth0 -p tcp -m multiport --destination-port
> <port1>,<port2>,<blablabla> -j REJECT

Use DROP not REJECT, with REJECT you send an ICMP message, so it's
filtered, not close