[dm-devel] [PATCH v3 1/4] crypto: add eboiv as a crypto API template

[Milan Broz]

On 29/10/2020 11:05, Gilad Ben-Yossef wrote:
>  
> +config CRYPTO_EBOIV
> +	tristate "EBOIV support for block encryption"
> +	default DM_CRYPT
> +	select CRYPTO_CBC
> +	help
> +	  Encrypted byte-offset initialization vector (EBOIV) is an IV
> +	  generation method that is used in some cases by dm-crypt for
> +	  supporting the BitLocker volume encryption used by Windows 8
> +	  and onwards as a backwards compatible version in lieu of XTS
> +	  support.
> +
> +	  It uses the block encryption key as the symmetric key for a
> +	  block encryption pass applied to the sector offset of the block.
> +	  Additional details can be found at
> +	  https://www.jedec.org/sites/default/files/docs/JESD223C.pdf

This page is not available. Are you sure this is the proper documentation?

I think the only description we used (for dm-crypt) was original Ferguson's Bitlocker doc:
https://download.microsoft.com/download/0/2/3/0238acaf-d3bf-4a6d-b3d6-0a0be4bbb36e/bitlockercipher200608.pdf

IIRC EBOIV was a shortcut I added to dm-crypt because we found no official terminology for this IV.
And after lunchtime, nobody invented anything better, so it stayed as it is now :-)

Milan