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From: Jason Opperisano <opie@817west.com>
To: netfilter@lists.netfilter.org
Subject: Re: Prevent traceroutes
Date: Thu, 19 May 2005 19:33:47 -0400	[thread overview]
Message-ID: <20050519233347.GA9462@bender.817west.com> (raw)
In-Reply-To: <20050519232314.GA9369@bender.817west.com>

On Thu, May 19, 2005 at 07:23:14PM -0400, Jason Opperisano wrote:
>   # standard UDP ports used by traceroute
>   iptables -A INPUT -p udp --dport 33434:33523 -j DROP
>   iptables -A FORWARD -p udp --dport 33434:33523 -j DROP
> 
>   # ICMP echo-req's w/ low TTL
>   iptables -A INPUT -p icmp --icmp-type 8 -m ttl --ttl-lt 5 -j DROP
>   iptables -A FORWARD -p icmp --icmp-type 8 -m ttl --ttl-lt 5 -j DROP

looking at that response--there's a situation screaming for a custom
chain:

  iptables -N DROP_TRACE
  iptables -A DROP_TRACE -p udp --dport 33434:33523 -j DROP
  iptables -A DROP_TRACE -p icmp --icmp-type 8 -m ttl --ttl-lt 5 -j DROP

  iptables -A INPUT -j DROP_TRACE
  iptables -A FORWARD -j DROP_TRACE

-j

--
"Announcer: Paw McTucket Beer. If you drink it, hot women will have
 sex in your backyard."
        --Family Guy


  reply	other threads:[~2005-05-19 23:33 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2005-05-19 22:07 Prevent traceroutes Kenneth Kalmer
2005-05-19 23:23 ` Jason Opperisano
2005-05-19 23:33   ` Jason Opperisano [this message]
2005-05-20  6:39     ` Taylor, Grant
2005-05-20  7:44       ` Taylor, Grant
2005-05-20 15:20         ` Jason Opperisano
2005-05-20 15:34           ` Taylor, Grant
2005-05-20 18:44           ` Charlie Brady
2005-05-20 19:03             ` Taylor, Grant
2005-05-20 19:37               ` Jason Opperisano
2005-05-23  7:01                 ` Jozsef Kadlecsik
2005-05-20  8:01       ` Kenneth Kalmer
2005-05-20  1:12 ` Sertys
2005-05-20 19:17 ` Sebastian Siewior

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