Python script to output Bitfi key material compatible with `brainflayer -x -t priv`.

bitfi_to_brainflayer.py

#!/usr/bin/env python

# This script accepts salt,passphrases pairs on STDIN seperated by a tab.
# Specify the coin symbol and indexes to generate via command line args.
#
# Appears to work fine with Bitcoin, Litecoin and Ethereum, probably works
# with many other coins as well.
#
# Don't participate in Bitfi's pay-to-play Bounty - it's a sham.


import sys
import hmac
import hashlib

import scrypt
from pybitcointools import *

def ci(s):
    acc = ""
    for c in s.upper():
        acc += str(ord(c)-64)
    return int(acc)

def coinkey(password, salt, coin):
    k_par = scrypt.hash(password, salt, N=32768, p=4, r=8, buflen=64)
    c_par = hashlib.sha256(salt).digest()
    param = hmac.new(c_par, k_par, hashlib.sha512).digest()
    (msk, mcc) = (param[0:32], param[32:64])
    master_key = bip32_serialize((PRIVATE, 0, b'\x00'*4, 0, mcc, msk+b'\x01'))
    return bip32_ckd(master_key, ci(coin) | 0x80000000)

def subkey(key, n):
    sub_key = bip32_ckd(key, n)
    return bip32_extract_key(sub_key)[0:64]

if __name__ == "__main__":
    coin = 'btc'
    n_start = 0
    n_end = 10
    if len(sys.argv) > 1:
        coin = sys.argv[1]
    if len(sys.argv) > 2:
        n_start = int(sys.argv[2])
        n_end = n_start+1
    if len(sys.argv) > 3:
        n_end = int(sys.argv[3])+1

    for line in sys.stdin:
        line = line.rstrip("\r\n")
        (salt, password) = line.split("\t")
        coin_key = coinkey(password, salt, coin)
        for n in xrange(n_start, n_end):
            print "%s:%s:%d:%s:%s" % (subkey(coin_key, n), coin, n, salt, password)