Re: Better than SYNcookies?

From: Alan Cox (alan@lxorguk.ukuu.org.uk)
Date: Mon Sep 25 2000 - 14:17:15 EST


> So is he right, is his solution better than SYNcookies and there is
> something to be learned from his solution? Or does someone need to take
> him to school on the issue.

He isnt preserving the negotiated TCP MSS.

Other issues:

- If his ISN is the ip address then its a constant which is far worse than
random and also usable for replay attacks

[ie I dial up log the cookie, wait for you to get the same line - and I can
 collect the dialup rack over time]

Alan

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