WalletCordova API Examination

BIP39 (Mnemonic)
-----------------

# Docs
# https://github.com/bitcoin/bips/blob/master/bip-0039.mediawiki

# Reference python impl
# https://github.com/trezor/python-mnemonic

# No C reference impl yet.

The plugin (plugins/it.greenaddress.cordova/BIP39.java) only exposes:

BIP39::calcSeed(salt, password)
    returns <block of data>

And theres a javascript impl of the same functionality here:

www/greenaddress.it/static/js/greenwallet/mnemonics/mnemonic_seed.js

The rest of the API is at:

www/greenaddress.it/static/js/greenwallet/mnemonics/services.js.

- How much do we want to expose? default wordlists or have the user pass them in etc.
- Settings (number of rounds, number of words/bits etc) should be changable ideally.
- Need to be able to register callbacks for GUIs to upadte progress etc
- Need callbacks for h/w as well

BIP38 (Passphrase protected private key)
----------------------------------------

# Docs
# https://github.com/bitcoin/bips/blob/master/bip-0038.mediawiki

Python impl at https://github.com/maxweisspoker/pybip38
C# impl at https://github.com/MetacoSA/NBitcoin/tree/master/NBitcoin/BIP38

No reference c impl yet.

The plugin (plugins/it.greenaddress.cordova/BIP39.java) only exposes:

BIP38::encrypt(key_json, password, cur_coin (BTC/BTT))
    data_json is a list of 32 byte values as ints
    BUG: Java doesn't validate the int passed in - will casting throw in java? still bad, no good error msg
    returns serialisedKey: KeyFormatter(password, network).serializeKey(ECKeyPair(dat_json, compressed=true))

BIP38::decrypt(b58, password, cur_coin (BTC/BTT)
    b58 is the serialised key 
    returns keyPair: KeyFormatter(password, network).parseSerializeKey(b58)

BIP38::encrypt_raw(data_json, password)
    data_json is a list of 32 byte values as ints
    BUG: Java doesn't validate the int passed in - will casting throw in java? still bad, no good error msg
    returns <raw encrypted bytes>

BIP38::decrypt_raw(data_json, password)
    data_json is a list of 36 byte values as ints (32 + checksum)
    BUG: Java doesn't validate the int passed in - will casting throw in java? still bad, no good error msg
    returns <raw decrypted bytes>


- Why the 2 APIs, need to look at what bitsofproof lib is providing here
- Needs scrypt, c BSD lib here: https://github.com/technion/libscrypt but its windows unfriendly
- Do we want to include dependencies like scrypt and secp256k?
- Do we want to expose the underlying low level primitives?

- Language bindings - Java, Javascript, Python are a must.