From: "Daniel F. Chief Security Engineer -" <danielf@supportteam.net>
To: Don Cohen <don-netf@isis.cs3-inc.com>,
netfilter <netfilter@lists.netfilter.org>,
netfilter-devel@lists.netfilter.org
Subject: Re: Fwd: Re: Interesting request. block x.x.0.0
Date: Fri, 24 Jan 2003 08:53:13 -0600 [thread overview]
Message-ID: <200301240853.13635.danielf@supportteam.net> (raw)
In-Reply-To: <15920.37125.743591.125495@isis.cs3-inc.com>
Patrick Schaaf kindly pointed out that I could do this.
iptables -I INPUT -s 0.0.0.0/0.0.255.255 -j DROP
That will drop any IP that ends in 0.0
Thanks for every ones help.
I will also look into the u32 patch thanks again.
On Thursday 23 January 2003 19:04, you wrote:
> > I do not want to block every IP on say 45.208.0.0/16 just the ips ending
> > in 0.0 as the last two octets.
> >
> > I can write a tcpdump filter to find the traffic Im just not sure if we
> > have a way to craft a netfilter rule to do so. Or maybe the "recent"
> > patch could be of use. Although the dDoS included 65000 source IP
> > addresses. all ending in 0.0 for the ip address.
> >
> > the tcdump filter looks like this.
> >
> > tcpdump -nn -i eth0 'ip[18:2] == 00'
>
> The u32 match I recently posted can do this.
--
Daniel Fairchild - Chief Security Engineer | danielf@supportteam.net
The distance between nothing and infinity is always the same no matter how
close you get to nothing.
parent reply other threads:[~2003-01-24 14:53 UTC|newest]
Thread overview: expand[flat|nested] mbox.gz Atom feed
[parent not found: <15920.37125.743591.125495@isis.cs3-inc.com>]
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