From mboxrd@z Thu Jan  1 00:00:00 1970
From: Michael Hissler <mhis38@freenet.de>
Subject: Re: Rate Limiting After a Threshold
Date: Fri, 06 Jul 2007 12:22:33 +0200
Message-ID: <468E17E9.7030902@freenet.de>
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John Jung wrote:

[...]

>   I think hashlimit is the key, but it really just doesn't want to work
> for me.  For example, I've tried:
> 
>     iptables -A INPUT -p tcp --dport 23 -m hashlimit --hashlimit 1/hour
>       --hashlimit-mode srcip --hashlimit-burst 1 --hashlimit-name test
>       -j REJECT


The hashlimit match works the other way round. Try '-j ACCEPT' and
append a rule to drop/reject connections to this port.
You should also use the state match, as you want to filter connections,
not packets.

So try this:

iptables -A INPUT -m state --state ESTABLISHED -j ACCEPT
iptables -A INPUT -p tcp --dport 23 -m state --state NEW -m hashlimit
--hashlimit 1/hour --hashlimit-mode srcip --hashlimit-burst 1
--hashlimit-name test -j ACCEPT
iptables -A INPUT -p tcp --dport 23 -m state --state NEW -j REJECT

(If you enter the rules in this order, you can omit the '-m state
--state NEW' in the last rule, but OTOH it doesn't hurt.)


michael