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From: Matthias Urlichs <smurf@smurf.noris.de>
Newsgroups: smurf.list.linux.kernel
Subject: Re: [PATCH] Delete cryptoloop
Date: Thu, 22 Jul 2004 09:43:42 +0200
Organization: {M:U} IT Consulting
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Hi, James Morris wrote:

> It would be good if we could get some further review on the issue by an 
> independent, well known cryptographer.

Well, I'm not, but ...

AFAIK, the main issue is: If I write some data to the start of block N, I
get a bit pattern. If I write the same data *anywhere* else (the middle of
block N, the start of block M != N, a different on-disk bit pattern must
result.

If there are identical bit patterns, then the system is vulnerable.
Obviously, this vulnerability doesn't depend on whether you're using
cryptoloop or dm-crypt.

-- 
Matthias Urlichs