mnemonics_to_iota_seed.py

# -*- coding: utf-8 -*-
import sys, mnemonic, bip32utils
from six.moves import input
from iota.crypto.kerl import Kerl, conv

#===============================================================================
def MnemonicsToIotaSeed(recovery_words, 
                        passphrase='', 
                        bip44_account=0x00000000, 
                        bip44_page_index=0x00000000):
    """Recover an IOTA seed from the ledger Nano S recovery phrase

    Keyword arguments:
    recovery_words -- a list of 24 words (your ledger recovery phrase)
    passphrase -- a string containing the passphrase (only if set in ledger, not your pin number!)
    bip44_account -- an integer containing BIP44 path 'Account'
    bip44_page_index -- an integer containing BIP44 path 'Page index'
    """
    print("\nCalculating your IOTA seed...")
    
    master_seed     = mnemonic.Mnemonic.to_seed(mnemonic=' '.join(recovery_words), passphrase=passphrase)
    bip32_root_key  = bip32utils.BIP32Key.fromEntropy(master_seed)

    bip44_purpose_key       = bip32_root_key.ChildKey(0x8000002C)                       # Purpose
    bip44_coin_type_key     = bip44_purpose_key.ChildKey(0x8000107A)                    # CoinType
    bip44_account_key       = bip44_coin_type_key.ChildKey(0x80000000+bip44_account)    # Account
    bip44_page_index_key    = bip44_account_key.ChildKey(0x80000000+bip44_page_index)   # Page index

    if (sys.version_info.major >= 3):
        priv_key    = bytearray(bip44_page_index_key.PrivateKey())
        chain_code  = bytearray(bip44_page_index_key.C)
    else:
        priv_key    = bytearray.fromhex(bip44_page_index_key.PrivateKey().encode('hex'))
        chain_code  = bytearray.fromhex(bip44_page_index_key.C.encode('hex'))

    trits_out = []

    kerl = Kerl()
    kerl.k.update(priv_key[0:32] + chain_code[0:16] + priv_key[16:32] + chain_code[0:32])
    kerl.squeeze(trits_out)

    iota_seed = conv.trits_to_trytes(trits_out)

    print("Seed: %s, Length: %d" % (iota_seed, len(iota_seed)))

#===============================================================================
def InputRecoveryWords():
    print("\nPlease enter your Ledger Nano S recovery phrase now:")

    m = mnemonic.Mnemonic(language='english')

    recovery_words = []
    
    for i in range(24):
        while True:
            try:
                word = input("   word #%d: " % (i+1))
            except KeyboardInterrupt:
                return None
            
            if word == '':
                print("\nERROR: word #%d was empty!" % (i+1))
                continue

            try:
                m.wordlist.index(word)
            except ValueError:
                print("\nERROR: word '%s' is not in the BIP44 words list!" % (word))
                continue

            recovery_words.append(word)
            break
    
    return recovery_words

#===============================================================================
def InputPassphrase():
    print("\nPlease enter your Ledger Nano S passphrase now (only if set in the ledger, not your pin number!):")
    
    try:
        return input("   Ledger passphrase: ")
    except KeyboardInterrupt:
        return None

#===============================================================================
def RecoverSeed():
    print("\nWelcome to IOTA Ledger Nano seed recovery!")
    
    recovery_words = InputRecoveryWords()
    if recovery_words == None:
        return
    
    passphrase = InputPassphrase()
    if passphrase == None:
        return
    
    MnemonicsToIotaSeed(recovery_words, passphrase)

#===============================================================================
if __name__ == '__main__':
    RecoverSeed()