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Re: iptables & tcp wrappers

Subject: Re: iptables & tcp wrappers
Date: Mon, 4 Oct 2004 00:01:13 +0200
On 2004-09-29 harry wrote:
Whelan, Paul wrote:
"iptables -L --line-numbers" will show you the line numbers of the
rules.
"iptables -A INPUT -p tcp -s ! ONLY_IP_YOU_WANT --dport 22 -j DROP" will
block every connection to port 22 except ONLY_IP_YOU_WANT.

not really... a good firewall (IMHO) drops everything, rejects auth 
(nasty timeouts on ftp, irc, ... if you just drop auth), and accepts 
these 4(or 5) icmp requests:
"source-quench"
"parameter-problem"
"time-exceeded"
"destination-unreachable"
and your clients probably want the "echo-request" too :)

Add "fragmentation-needed" and "echo-reply".

Regards
Ansgar Wiechers
-- 
"Those who would give up liberty for a little temporary safety
deserve neither liberty nor safety, and will lose both."
--Benjamin Franklin

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