[dm-devel] [PATCH 3/3] dm-crypt: Implement eboiv - encrypted byte-offset initialization vector.

[Herbert Xu]

On Fri, Jul 05, 2019 at 08:32:03AM +0200, Ard Biesheuvel wrote:
>
> > AFAICS this is using the same key as the actual data.  So why
> > don't you combine it with the actual data when encrypting/decrypting?
> >
> > That is, add a block at the front of the actual data containing
> > the little-endian byte offset and then use an IV of zero.
> >
> 
> That would only work for encryption.

True.  So this doesn't obviate the need to access the single-block
cipher.  But the code probably should still do it that way for
encryption for performance reasons.

Cheers,
-- 
Email: Herbert Xu <herbert at gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
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