Argon2

[Jussi Kivilinna]

On 22.10.2021 19.49, Werner Koch wrote:
> On Wed, 20 Oct 2021 19:49, Jussi Kivilinna said:
> 
>> One thing I'm not sure is about is how to introduce Argon2 to KDF interface.
>> Argon2 has more parameters (degree of parallelism p, memory size m, number of
>> passes t) than what libgcrypt takes with `gcry_kdf_derive()`, which only takes
>> `iterations`. So we'd need new interface for Argon2.
> 
> Well, we may make use of the SUBALGO and put sveral parameters into
> ITERATIONS.  This would allow us to add just a a couple of macros and
> save the trouble of adding a new interface.
> 

RFC defines two 32-bit parameters (m and t) and one 24-bit (p). We would
need to use reduced value ranges for these if passed through ITERATIONS.
Large values won't probably have practical use but it would be nice to
support full value ranges. Maybe KEYBUFFER could be used for passing
pointer to Argon2 parameter structure?

-Jussi

> 
> Shalom-Salam,
> 
>     Werner
>