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. Just FWIW, Mike "Silby" Silbersack To Unsubscribe: send mail to [EMAIL PROTECTED] with "unsubscribe freebsd-net" in the body of the message
