[dm-crypt] why nbytes for block cipher encrypt/decrypt is only 512 bytes

Milan Broz mbroz at redhat.com
Fri Apr 20 13:35:42 CEST 2012

On 04/20/2012 12:22 PM, Arno Wagner wrote:
> I think you cannot. As long as the block-size for the IV scheme
> is 512 bytes, you are stuck with encrypting 512 bytes at a time,
> as they have their own IV. 

Yes for now, 512bytes sector as internal device-mapper unit ==
size of encryption unit in dmcrypt.

There was several discussions about it (see list archive) and maybe
in future there will be an option to make it configurable (it will
cause several incompatibility problems though) but for now, 512 is
the only supported value.


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