ed448: Ed448 Implementation

[ashWhiteHat]

Part of #8

Hi there.
I implemented ed448.

Implementation and documentation are aligned with ed25519 implementation.

What I did

• hex display and serialization
• pkcs v1 private/public key encoding and decoding
• seder serializers and deserializers

Issues

I don't know how to convert pkcs v1 to v2 format so I couldn't implement pkcs v2 enc/dec.

discussion

code duplication

Ed448 implementation is almost the same as Ed25519.
There is huge code duplication.
PublicKeyBytes is only the difference between Ed448 and Ed25519.

In Ed25519, the public key bytes length is 32, and type [u8; 32] supports Default.
However, in Ed448, the public key bytes length is 57, and type [u8; 57] doesn't support Default.
I implemented PublicKeyBytes as a struct in Ed448.

If we integrate both formats, we would be able to implement them as a macro.

crate name

ed448 crate was already taken. I would like to know what name we should name.

Todo

• support pkcs v2
• ignore code duplication or not
• decide crate name

I would appreciate it if you could confirm.
Thank you.