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From: Alex Flex <aflexzor@gmail.com>
To: netfilter@vger.kernel.org
Subject: Question about behaviour of rule in a syn attack.
Date: Fri, 12 Apr 2013 17:05:30 -0600	[thread overview]
Message-ID: <5168933A.30409@gmail.com> (raw)

Greetings !

Id be thankful if somebody can shed some light here:

If Iam getting a syn attack, and I have syn cookies enabled via sysctl 
would any of these two rules match  those connections?


iptables -A INPUT -p tcp --syn --dport 80 -m connlimit --connlimit-above 
10 --connlimit-mask 32 -j DROP
iptables -A INPUT -p tcp --syn --dport 80 -m hashlimit  
--hashlimit-above 25/second --hashlimit-srcmask 32 --hashlimit-name 
IP_LIMIT_REQ  -j DROP

Or do these only apply to connections that have undergone the handshake?

Thanks
Alex

                 reply	other threads:[~2013-04-12 23:05 UTC|newest]

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