[PATCH 1/9] crypto,fs: Separate out hkdf_extract() and hkdf_expand()

[Eric Biggers]

On Tue, Oct 15, 2024 at 05:05:40PM +0200, Hannes Reinecke wrote:
> On 10/14/24 21:38, Eric Biggers wrote:
> > On Fri, Oct 11, 2024 at 05:54:22PM +0200, Hannes Reinecke wrote:
> > > Separate out the HKDF functions into a separate module to
> > > to make them available to other callers.
> > > And add a testsuite to the module with test vectors
> > > from RFC 5869 to ensure the integrity of the algorithm.
> > 
> > integrity => correctness
> > 
> Okay.
> 
> > > +config CRYPTO_HKDF
> > > +	tristate
> > > +	select CRYPTO_SHA1 if !CONFIG_CRYPTO_MANAGER_DISABLE_TESTS
> > > +	select CRYPTO_SHA256 if !CONFIG_CRYPTO_MANAGER_DISABLE_TESTS
> > > +	select CRYPTO_HASH2
> > 
> > Any thoughts on including SHA512 tests instead of SHA1, given that SHA1 is
> > obsolete and should not be used?
> > 
> Hmm. The original implementation did use SHA1, so I used that.
> But sure I can look into changing that.

If you're talking about fs/crypto/hkdf.c which is where you're borrowing the
code from, that uses SHA512.

- Eric