[dm-devel] xts fuzz testing and lack of ciphertext stealing support

[Ard Biesheuvel]

On Sat, 27 Jul 2019 at 19:04, Milan Broz <gmazyland at gmail.com> wrote:
>
> On 27/07/2019 07:39, Ard Biesheuvel wrote:
> > Thanks for the additional test vectors. They work fine with my SIMD
> > implementations for ARM [0], so this looks like it might be a CAAM
> > problem, not a problem with the test vectors.
> >
> > I will try to find some time today to run them through OpenSSL to double check.
>
> I shamelessly copied your test vectors to my vector test for cryptsetup backend.
>
> Both OpenSSL and gcrypt XTS implementation passed all tests here!
>
> If interested - this is copy of backend we have in cryptsetup, vectors added in crypto-vectors.c
> (there are some hard defines in Makefile, cryptsetup uses autoconf instead).
>   OpenSSL: https://github.com/mbroz/cryptsetup_backend_test
>   gcrypt branch: https://github.com/mbroz/cryptsetup_backend_test/tree/gcrypt
>
> Once kernel AF_ALG supports it, I can easily test it the same way.
>

Thanks for confirming. So we can be reasonably confident that the test
vectors contributed by Pascal are sound.

I'll try to send out my ARM/arm64 changes shortly. However, I won't
have any access to hardware until end of next month, so they are
tested on QEMU only, which means I won't be able to provide any
performance numbers.