[dm-devel] [PATCH v3 0/6] crypto: switch to crypto API for ESSIV generation

[Milan Broz]

On 19/06/2019 18:29, Ard Biesheuvel wrote:
> This series creates an ESSIV template that produces a skcipher or AEAD
> transform based on a tuple of the form '<skcipher>,<cipher>,<shash>'
> (or '<aead>,<cipher>,<shash>' for the AEAD case). It exposes the
> encapsulated sync or async skcipher/aead by passing through all operations,
> while using the cipher/shash pair to transform the input IV into an ESSIV
> output IV.
> 
> This matches what both users of ESSIV in the kernel do, and so it is proposed
> as a replacement for those, in patches #2 and #4.
> 
> This code has been tested using the fscrypt test suggested by Eric
> (generic/549), as well as the mode-test script suggested by Milan for
> the dm-crypt case. I also tested the aead case in a virtual machine,
> but it definitely needs some wider testing from the dm-crypt experts.
> 
> Changes since v2:
> - fixed a couple of bugs that snuck in after I'd done the bulk of my
>   testing
> - some cosmetic tweaks to the ESSIV template skcipher setkey function
>   to align it with the aead one
> - add a test case for essiv(cbc(aes),aes,sha256)
> - add an accelerated implementation for arm64 that combines the IV
>   derivation and the actual en/decryption in a single asm routine

I run tests for the whole patchset, including some older scripts and seems
it works for dm-crypt now.

For the new CRYPTO_ESSIV option - dm-crypt must unconditionally
select it (we rely on all IV generators availability in userspace),
but that's already done in patch 4.

Thanks,
Milan