Substrate BIP39

[Lohann]

Description

This PR creates a new package that implements Substrate-BIP39, necessary for extracting the seed from mneumonic phrases.

Substrate uses a custom implementation of BIP39, which uses different derivation functions depending of the signature scheme being used, examples:

Mneumonic: "bottom drive obey lake curtain smoke basket hold race lonely fit walk//Alice"
   Scheme: Sr25519
     Seed: 0xe5be9a5092b81bca64be81d212e7f2f9eba183bb7a90954f7b76361f6edb5c0a

Mneumonic: "bottom drive obey lake curtain smoke basket hold race lonely fit walk//Alice"
   Scheme: Ed25519
     Seed: 0xabf8e5bdbe30c65656c0a3cbd181ff8a56294a69dfedd27982aace4a76909115

Mneumonic: "bottom drive obey lake curtain smoke basket hold race lonely fit walk//Alice"
   Scheme: ECDSA
     Seed: 0xcb6df9de1efca7a3998a8ead4e02159d5fa99c3e0d4fd6432667390bb4726854

Obs: Currently only Ed25519 is supported.

The output of this package was compared against the output of Subkey Tool

TODO

• [x] Substrate BIP39 seed from entropy
• [x] Generate mneumonic
• [x] Support Ed25519 Key derivation
• [ ] Support Sr25519 Private Key derivation
• [ ] Support Sr25519 Public Key derivation
• [ ] Support Ecdsa derivation
• [ ] Documentation
• [ ] Update Readme.md

Will do the Sr25519 and ECDSA support in follow up PR, because currently we only support Ed25519 signatures.

References:

• https://github.com/bitcoin/bips/blob/master/bip-0039.mediawiki
• https://github.com/paritytech/substrate-bip39/tree/master