curve25519 and curve448 support

[Spomky]

The RFC7748 introduces two new curves: curve25519 and curve448.

Do you plan to add a support for these two curves?

[afk11]

They would be nice, we'd have to check the algorithm is suitable. It might be more effort than adding it to the CurveFactory, but worthwhile all the same.

[Spomky]

Great news.
I found these repositories that provide Ed25519 implementations. That could help you.

[afk11]

Interesting, I'll give that a look! I read over the RFC the other day, it seems to have lots of details not seen in PHPECC today. It wouldn't be as straightforward as I would have hoped!

The extension is probably faster than we'll be able to pull off in pure PHP, but I'll have to check it later!

[Spomky]

Well... yes you are right, this library will never be as fast as an extension.
I decided to try the extension mentioned above and the first tests that I ran gave me good results.

[paragonie-scott]

I've implemented X25519 and Ed25519 in sodium_compat if you'd like to either reference that implementation (or just add sodium_compat as a dependency).

Take note that it has yet to be audited and therefore should be viewed as experimental until we can get that done.

[paragonie-scott]

We've tagged v1 so it may be worth adopting sodium_compat to fulfill your needs for Curve25519.

[Spomky]

Closing as the curves Ed25519/X25519 are available by other means (libCrypto or PHP 7.2).
An implementation of the curves Ed448 and X448 is still missing, but it looks like these curves are not widely used.