Re: [PATCH 4/6] crypto: hkdf - RFC5869 Key Derivation Function

Herbert Xu
2019-01-12T09:56:36Z

On Fri, Jan 11, 2019 at 09:12:54PM -0800, Eric Biggers wrote:
> Hi Stephan,
>
> On Fri, Jan 11, 2019 at 08:10:39PM +0100, Stephan Müller wrote:
> > The RFC5869 compliant Key Derivation Function is implemented as a
> > random number generator considering that it behaves like a deterministic
> > RNG.
> >
>
> Thanks for the proof of concept! I guess it ended up okay. But can you explain
> more the benefits of using the crypto_rng interface, as opposed to just some
> crypto_hkdf_*() helper functions that are exported for modules to use?

I agree. I see no benefit in adding this through the RNG API as
opposed to just providing it as a helper. If some form of hardware
acceleration were to eventuate in the future we could always revisit
this.

Cheers,
--
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
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