From owner-freebsd-security  Fri Jan 21 11:22:23 2000
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Subject: Re: Re[2]: bugtraq posts:  stream.c - new FreeBSD exploit?
In-Reply-To: <12643.000121@sandy.ru> from Vladimir Dubrovin at "Jan 21, 2000
 03:26:08 pm"
To: Vladimir Dubrovin <vlad@sandy.ru>
Date: Fri, 21 Jan 2000 11:21:15 -0800 (PST)
Cc: Dima Ruban <dima@rdy.com>, freebsd-security@FreeBSD.ORG
Organization: HackerDome
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From: dima@rdy.com (Dima Ruban)
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Vladimir Dubrovin writes:
> Sure  you  cann't  detect invalid ACK packets with ipfw, but IMHO ipfw
> (then  dummynet  is  used)  can be used to eliminate any kind of flood
> attack with amount of small packets. Rules like
> 
> ipfw pipe 10 config delay 50 queue 5 packets
> ipfw add pipe 10 tcp from any to MYHOST in via EXTERNAL
> 
> should  limit  ipfw  to  allow only 5 tcp packets in 50 ms for MYHOST,
> more packets will be dropped. But I don't think it's best solution.

They use random source address.

> 
> 
>   +=-=-=-=-=-=-=-=-=+
>   |Vladimir Dubrovin|
>   | Sandy Info, ISP |
>   +=-=-=-=-=-=-=-=-=+
> 
> 

-- dima


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