[cod] CoD2 UDP flood

Tue Feb 28 02:47:45 EST 2012

Well I can say the iptables rules have been running fantastically. I added
a few tweaks such as not blocking the server's own set of IP's (there are
quite a few internal queries going on), and also setting the hashlimit-mode
to be based on source and destination IP since I have different server
instances on different addresses, and I wanted a little more granularity to
the matching. My ingress rates are still noticeably higher than they used
to be, but at least the outbound bandwidth isn't being exploited anymore.

Does anyone know the default value for hashlimit-htable-expire? I haven't
been able to find it, so I've manually set it to 30 seconds.

On 02/24/2012 03:38 PM, River Hosting wrote:
>
> Hello again guys,
>
>
>
> I was adding some new rules into the firewall and it looks like the
> flooding has stopped!
>
>
>
> Now using;
>
> - *serverark* (recently posted on this list)
>
> - *getstatus_ban.sh* (recently posted aswell)
>
> - *iptables*
>
>
>
> Since this morning the traffic dropped from 6 Mbit/s to 45 Kb/s.
>
> When filtering, shutting down all gameservers running on your box for
> about 24-48 hours may do the trick. After that time just reboot them and
> let the magic happen... :)
>
>
>
>
>
> Met vriendelijke groeten,
>
> With kind regards,
>
> Julian Maartens
> River Hosting
>
> info at riverhosting.nl
> http://www.riverhosting.nl
>
>
>
> *Van:* Marco Padovan [mailto:evcz at evcz.tk <evcz at evcz.tk>]
> *Verzonden:* vrijdag 24 februari 2012 14:05
> *Aan:* Call of Duty server admin list.
> *Onderwerp:* Re: [cod] CoD2 UDP flood
>
>
>
> You can either use the one you linked from modsrepository or the more
> "complex" one that was posted on this list
>
> Il 24/02/2012 14:03, david.lauriou at wanadoo.fr ha scritto:
>
> the rules is ?
>
>
>
>  ----- Original Message -----
>
> *From:* Marco Padovan <evcz at evcz.tk>
>
> *To:* cod at icculus.org
>
> *Sent:* Friday, February 24, 2012 2:00 PM
>
> *Subject:* Re: [cod] CoD2 UDP flood
>
>
>
> that rule is very basic.
>
> cod1, cod1.5, cod2 and cod4 all suffer the same problem and are exploited
> in the same exact way.
>
> So an iptables that fixes the cod4 problem works also for cod2 and cod1
>
> Il 24/02/2012 13:51, david.lauriou at wanadoo.fr ha scritto:
>
> i've find this :
> http://wiki.modsrepository.com/index.php/Call_of_Duty_4:_Servers
>
> its for cod4 not for COD2 !
>
>
>
>  ----- Original Message -----
>
> *From:* Marco Padovan <evcz at evcz.tk>
>
> *To:* cod at icculus.org
>
> *Sent:* Friday, February 24, 2012 1:49 PM
>
> *Subject:* Re: [cod] CoD2 UDP flood
>
>
>
> NO!
>
> Read the messages that got posted in the last 2 days...
>
> This should be a proper ruleset:
> http://icculus.org/pipermail/cod/2012-February/015927.html
>
> Il 24/02/2012 13:47, david.lauriou at wanadoo.fr ha scritto:
>
> like this ?
>
>
>
> IPTABLES -A INPUT -p UDP -m length --length 42 -m recent --set --name getstatus_cod
>
> IPTABLES -A INPUT -p UDP -m string --algo bm --string "getstatus" -m recent --update --seconds 1 --hitcount 20 --name getstatus_cod -j DROP
>
>  ----- Original Message -----
>
> *From:* Marco Padovan <evcz at evcz.tk>
>
> *To:* Call of Duty server admin list. <cod at icculus.org>
>
> *Sent:* Friday, February 24, 2012 1:35 PM
>
> *Subject:* Re: [cod] CoD2 UDP flood
>
>
>
> iptables rules
>
> Il 24/02/2012 13:28, david.lauriou at wanadoo.fr ha scritto:
>
> for COD4 what is the best method to remove udp Flooding exploit ?
>
>
>
>  ----- Original Message -----
>
> *From:* Marco Padovan <evcz at evcz.tk>
>
> *To:* Call of Duty server admin list. <cod at icculus.org>
>
> *Sent:* Friday, February 24, 2012 12:10 PM
>
> *Subject:* Re: [cod] CoD2 UDP flood
>
>
>
> Be aware that there are two different ways to talk about offset: packet
> offset (includes header) and payload offset (does not include header)
>
> Il 24/02/2012 10:41, Geoff Goas ha scritto:
>
> You're right, and I see my error. That is frustrating because I have no
> idea why it doesn't work with the offset specified then.
>
> On Fri, Feb 24, 2012 at 4:10 AM, Luca Farflame Fabbro <
> farflame at cybergames.it> wrote:
>
> Try this command
>
> tcpdump -c 4 -nnvvvXS dst port 28960
>
> where port is the port that you want to monitor
>
> should be something like
>
>
>
>         0x0000:  4500 002b 35b3 0000 7511 179b b612 80ad  E..+5...u.......
>
>         0x0010:  c0a8 010c 7012 7120 0017 0000 ffff ffff  ....p.q.........
>
>         0x0020:  6765 7473 7461 7475 730a 0000 0000       getstatus.....
>
>
>
> On Feb 24, 2012, at 9:54 AM, Geoff Goas wrote:
>
>
>
>
>
>  That is strange, because if I use those values, it does not work. If I
> use "--from 31" alone, then it works. As soon as I change that to 32, it
> stops working. When I inspect the packets in Wireshark, the "getstatus"
> string starts at offset 48 if counting from 1. Would there be a way for
> iptables to print to log what it sees in the specified offset range?
>
> On Fri, Feb 24, 2012 at 3:28 AM, Luca Farflame Fabbro <
> farflame at cybergames.it> wrote:
>
> It doesn't matter the length of the packet.
>
> That rule will try to find the string "gestatus" starting at position 32
> bytes from start of packet and searching for it at maximum at position 41.
>
> The Q3 protocol for that command expects the string to be in that range.
>
>
>
> On Feb 24, 2012, at 1:11 AM, Geoff Goas wrote:
>
>
>
>  Is the offset range of 32-41 based on a 60-byte packet?
>
> On Thu, Feb 23, 2012 at 10:34 AM, Marco Padovan <evcz at evcz.tk> wrote:
>
> iptables -A INPUT -p udp -m string --string "getstatus" --algo bm --from
> 32 --to 41 -j DROP
>
> --
> *Geoff Goas
> Systems Engineer*
>
> _______________________________________________
> cod mailing list
> cod at icculus.org
> http://icculus.org/mailman/listinfo/cod
>
>
>
>
> _______________________________________________
> cod mailing list
> cod at icculus.org
> http://icculus.org/mailman/listinfo/cod
>
>
>
>
> --
> *Geoff Goas
> Systems Engineer*
>
> _______________________________________________
> cod mailing list
> cod at icculus.org
> http://icculus.org/mailman/listinfo/cod
>
>
>
>
> _______________________________________________
> cod mailing list
> cod at icculus.org
> http://icculus.org/mailman/listinfo/cod
>
>
>
>
> --
> *Geoff Goas
> Systems Engineer*
>
>
>
>
>
>
>  _______________________________________________
>
> cod mailing list
>
> cod at icculus.org
>
> http://icculus.org/mailman/listinfo/cod
>
>  ------------------------------
>
> _______________________________________________
> cod mailing list
> cod at icculus.org
> http://icculus.org/mailman/listinfo/cod
>
>
>
>
>
>
>  _______________________________________________
>
> cod mailing list
>
> cod at icculus.org
>
> http://icculus.org/mailman/listinfo/cod
>
>  ------------------------------
>
> _______________________________________________
> cod mailing list
> cod at icculus.org
> http://icculus.org/mailman/listinfo/cod
>
>
>
>
>
>
>  _______________________________________________
>
> cod mailing list
>
> cod at icculus.org
>
> http://icculus.org/mailman/listinfo/cod
>
>  ------------------------------
>
> _______________________________________________
> cod mailing list
> cod at icculus.org
> http://icculus.org/mailman/listinfo/cod
>
>
>
>
>
>
>  _______________________________________________
>
> cod mailing list
>
> cod at icculus.org
>
> http://icculus.org/mailman/listinfo/cod
>
>  ------------------------------
>
> _______________________________________________
> cod mailing list
> cod at icculus.org
> http://icculus.org/mailman/listinfo/cod
>
>
>
>
>
>
>  _______________________________________________
>
> cod mailing list
>
> cod at icculus.org
>
> http://icculus.org/mailman/listinfo/cod
>
>
>
>
>
>  _______________________________________________
>
> cod mailing list
>
> cod at icculus.org
>
> http://icculus.org/mailman/listinfo/cod
>
>
>
>
>  _______________________________________________
>
> cod mailing list
>
> cod at icculus.org
>
> http://icculus.org/mailman/listinfo/cod
>
>
> _______________________________________________
> cod mailing list
> cod at icculus.org
> http://icculus.org/mailman/listinfo/cod
>
>

-- 
*Geoff Goas
Systems Engineer*
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://icculus.org/pipermail/cod/attachments/20120228/4cd6b2ec/attachment-0001.htm>