Re: [PATCH 6/6] crypto: sha256_generic - Use sha256_transform from generic sha256 lib

From: Eric Biggers
Date: Sat Aug 17 2019 - 01:14:45 EST


On Fri, Aug 16, 2019 at 11:16:11PM +0200, Hans de Goede wrote:
> Drop the duplicate sha256_transform function from crypto/sha256_generic.c
> and use the implementation from lib/crypto/sha256.c instead.
> "diff -u lib/crypto/sha256.c sha256_generic.c"
> shows that both implementations are identical.
>
> Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>

Hi Hans, thanks for doing this!

I'm a little concerned that the only sha256 lib function which sha256_generic.c
calls is sha256_transform(). This means that sha256_init(), sha256_update(),
and sha256_final() are not tested by the crypto self-tests. They could be
broken and we wouldn't know.

IMO, it would be better to make sha256_generic.c use sha256_init(),
sha256_update(), and sha256_final() rather than using sha256_base.h.
Then we'd get test coverage of both the sha256 lib, and of sha256_base.h
via the architecture-specific implementations.

To do this you'll also need to add sha224_init(), sha224_update(), and
sha224_final(). But that's straightforward.

- Eric