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Re: SYN flood messages flooding my mailbox

  • From: Curtis Villamizar
  • Date: Tue Sep 17 13:58:05 1996 
In message <[email protected]>, Avi Freedman writes:
> 
> > implementation.  This is a denial of service exposure that has gone
> > unaddressed in host implementations until recently.  BSD now uses a
> > hash table on the TCP PCBs (protocol control blocks in the kernel) and
> > with change of removal of the check can support close to 64K-2000 PCBs
> 
> Hmm.  Interesting.  I was told that NetBSD did not...
> Which version of BSD should I look at?  A hash table on a static array of
> PCBs is a much better solution than letting a linked list get to 2000
> entries...

Oops.  That's in a BSDI patch (PATCH K210-019) but I'm not sure about
FreeBSD or NetBSD distributions since I don't have one handy.

Curtis

ps- (My 6 year old has a FreeBSD system, but its 2.0.5.  Got to get
him to upgrade. :)
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