Re: XTS cipher mode for cluster file encryption

On Fri, Oct 15, 2021 at 3:22 PM Stephen Frost <sfrost@snowman.net> wrote:
> Specifically: The default cipher for LUKS is nowadays aes-xts-plain64
>
> and then this:
>
> https://gitlab.com/cryptsetup/cryptsetup/-/wikis/DMCrypt
>
> where plain64 is defined as:
>
> plain64: the initial vector is the 64-bit little-endian version of the
> sector number, padded with zeros if necessary
>
> That is, the default for LUKS is AES, XTS, with a simple IV.  That
> strikes me as a pretty ringing endorsement.

Yes, that sounds promising. It might not hurt to check for other
precedents as well, but that seems like a pretty good one.

I'm not very convinced that using the LSN for any of this is a good
idea. Something that changes most of the time but not all the time
seems more like it could hurt by masking fuzzy thinking more than it
helps anything.

-- 
Robert Haas
EDB: http://www.enterprisedb.com