Re: [PATCH v2 0/2] crypto: LEA block cipher implementation

[Eric Biggers <ebiggers@kernel.org>]

On Fri, Jun 02, 2023 at 03:05:16PM +0900, Dongsoo Lee wrote:
> Additionally, we are exploring the possibility of using `blk-crypto` for
> encryption. Currently, the ciphers available for `blk-crypto` are
> AES-256-XTS, AES-128-CBC-ESSIV, Adiantum, and SM4-XTS. We would like to add
> LEA-256-XTS to these.
> 
> ( https://github.com/torvalds/linux/blob/master/block/blk-crypto.c#L21 )
> 
> Instead of disk encryption, it is also possible to use `fscrypt` to encrypt
> the file system for data-at-rest environments. `fscrypt` currently supports
> AES-256-XTS, AES-256-CTS-CBC, AES-128-CBC-ESSIV, AES-128-CTS-CBC, SM4-XTS,
> SM4-CTS-CBC, Adiantum, and AES-256-HCTR2.
> 
> ( https://github.com/torvalds/linux/blob/master/fs/crypto/keysetup.c#L16 )
> 

Currently the only user of blk-crypto is fscrypt.  So the above two paragraphs
are really talking about the same thing.

I haven't seen any patch that proposes adding LEA support to fscrypt.  Also, I'm
not sure that the information you've provided so far is sufficient motivation
for adding it to fscrypt.  I did recently allow another national pride cipher,
SM4, to be added to fscrypt, but that was only because a user said they were
being *required* to use SM4.  It's not clear that's the case for LEA.

- Eric