Mike Silbersack wrote: > > On Wed, 26 Dec 2001, Randall Stewart wrote: > > > This comment facinates me. The reason we made SACK's in SCTP > > revokeable is due to the potential DOS attack that someone > > can supposedly lauch if you don't allow the stack to revoke. > > > > I can actually see the reason that Sally made the comments > > and had us change it so that SACK's are revokeable. However > > you argue to the contrary and I wonder which is correct. > > > > If you do not allow revoking it is the same as if a protocol > > does not hold a drain() fucntion. A attacker could easily > > stuff a lot of out-of-order segments at you and thus > > fill up all your mbuf's or clusters (in my current testing > > case). This would then yeild a DOS since you could no longer > > receive any segments and leave you high and dry.... > > Heh, you nailed the reverse of the problem we've seen: Right now the easy > way to cause exhaustion is to fill up _send_ buffers, via netkill. I > guess if we solve that problem, out of order segments could be used for an > attack too. >
Mike: Interesting problem.. but I was thinking in terms of a outside attacker.. not someone who has a login id on your machine. That leads down another path... i.e. local machine security. R > Just FWIW, > > Mike "Silby" Silbersack > > To Unsubscribe: send mail to [EMAIL PROTECTED] > with "unsubscribe freebsd-net" in the body of the message -- Randall R. Stewart [EMAIL PROTECTED] 815-342-5222 (cell phone) To Unsubscribe: send mail to [EMAIL PROTECTED] with "unsubscribe freebsd-net" in the body of the message
