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bitcoin.py
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bitcoin.py
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# -*- coding: utf-8 -*-
#!/usr/bin/env python
#
# Electrum - lightweight Bitcoin client
# Copyright (C) 2011 thomasv@gitorious
#
# Permission is hereby granted, free of charge, to any person
# obtaining a copy of this software and associated documentation files
# (the "Software"), to deal in the Software without restriction,
# including without limitation the rights to use, copy, modify, merge,
# publish, distribute, sublicense, and/or sell copies of the Software,
# and to permit persons to whom the Software is furnished to do so,
# subject to the following conditions:
#
# The above copyright notice and this permission notice shall be
# included in all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
# BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
# ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
# CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
# SOFTWARE.
import hashlib
import base64
import os
import re
import hmac
import version
from util import print_error, InvalidPassword
import ecdsa
import aes
################################## transactions
FEE_STEP = 10000
RECOMMENDED_FEE = 50000
COINBASE_MATURITY = 100
COIN = 100000000
# supported types of transction outputs
TYPE_ADDRESS = 0
TYPE_PUBKEY = 1
TYPE_SCRIPT = 2
# AES encryption
EncodeAES = lambda secret, s: base64.b64encode(aes.encryptData(secret,s))
DecodeAES = lambda secret, e: aes.decryptData(secret, base64.b64decode(e))
def strip_PKCS7_padding(s):
"""return s stripped of PKCS7 padding"""
if len(s)%16 or not s:
raise ValueError("String of len %d can't be PCKS7-padded" % len(s))
numpads = ord(s[-1])
if numpads > 16:
raise ValueError("String ending with %r can't be PCKS7-padded" % s[-1])
if s[-numpads:] != numpads*chr(numpads):
raise ValueError("Invalid PKCS7 padding")
return s[:-numpads]
# backport padding fix to AES module
aes.strip_PKCS7_padding = strip_PKCS7_padding
def aes_encrypt_with_iv(key, iv, data):
mode = aes.AESModeOfOperation.modeOfOperation["CBC"]
key = map(ord, key)
iv = map(ord, iv)
data = aes.append_PKCS7_padding(data)
keysize = len(key)
assert keysize in aes.AES.keySize.values(), 'invalid key size: %s' % keysize
moo = aes.AESModeOfOperation()
(mode, length, ciph) = moo.encrypt(data, mode, key, keysize, iv)
return ''.join(map(chr, ciph))
def aes_decrypt_with_iv(key, iv, data):
mode = aes.AESModeOfOperation.modeOfOperation["CBC"]
key = map(ord, key)
iv = map(ord, iv)
keysize = len(key)
assert keysize in aes.AES.keySize.values(), 'invalid key size: %s' % keysize
data = map(ord, data)
moo = aes.AESModeOfOperation()
decr = moo.decrypt(data, None, mode, key, keysize, iv)
decr = strip_PKCS7_padding(decr)
return decr
def pw_encode(s, password):
if password:
secret = Hash(password)
return EncodeAES(secret, s.encode("utf8"))
else:
return s
def pw_decode(s, password):
if password is not None:
secret = Hash(password)
try:
d = DecodeAES(secret, s).decode("utf8")
except Exception:
raise InvalidPassword()
return d
else:
return s
def rev_hex(s):
return s.decode('hex')[::-1].encode('hex')
def int_to_hex(i, length=1):
s = hex(i)[2:].rstrip('L')
s = "0"*(2*length - len(s)) + s
return rev_hex(s)
def var_int(i):
# https://en.bitcoin.it/wiki/Protocol_specification#Variable_length_integer
if i<0xfd:
return int_to_hex(i)
elif i<=0xffff:
return "fd"+int_to_hex(i,2)
elif i<=0xffffffff:
return "fe"+int_to_hex(i,4)
else:
return "ff"+int_to_hex(i,8)
def op_push(i):
if i<0x4c:
return int_to_hex(i)
elif i<0xff:
return '4c' + int_to_hex(i)
elif i<0xffff:
return '4d' + int_to_hex(i,2)
else:
return '4e' + int_to_hex(i,4)
def sha256(x):
return hashlib.sha256(x).digest()
def Hash(x):
if type(x) is unicode: x=x.encode('utf-8')
return sha256(sha256(x))
hash_encode = lambda x: x[::-1].encode('hex')
hash_decode = lambda x: x.decode('hex')[::-1]
hmac_sha_512 = lambda x,y: hmac.new(x, y, hashlib.sha512).digest()
def is_new_seed(x, prefix=version.SEED_PREFIX):
import mnemonic
x = mnemonic.normalize_text(x)
s = hmac_sha_512("Seed version", x.encode('utf8')).encode('hex')
return s.startswith(prefix)
def is_old_seed(seed):
import old_mnemonic
words = seed.strip().split()
try:
old_mnemonic.mn_decode(words)
uses_electrum_words = True
except Exception:
uses_electrum_words = False
try:
seed.decode('hex')
is_hex = (len(seed) == 32 or len(seed) == 64)
except Exception:
is_hex = False
return is_hex or (uses_electrum_words and (len(words) == 12 or len(words) == 24))
def seed_type(x):
if is_old_seed(x):
return 'old'
elif is_new_seed(x):
return 'standard'
elif is_new_seed(x, version.SEED_PREFIX_2FA):
return '2fa'
return ''
is_seed = lambda x: bool(seed_type(x))
# pywallet openssl private key implementation
def i2o_ECPublicKey(pubkey, compressed=False):
# public keys are 65 bytes long (520 bits)
# 0x04 + 32-byte X-coordinate + 32-byte Y-coordinate
# 0x00 = point at infinity, 0x02 and 0x03 = compressed, 0x04 = uncompressed
# compressed keys: <sign> <x> where <sign> is 0x02 if y is even and 0x03 if y is odd
if compressed:
if pubkey.point.y() & 1:
key = '03' + '%064x' % pubkey.point.x()
else:
key = '02' + '%064x' % pubkey.point.x()
else:
key = '04' + \
'%064x' % pubkey.point.x() + \
'%064x' % pubkey.point.y()
return key.decode('hex')
# end pywallet openssl private key implementation
############ functions from pywallet #####################
def hash_160(public_key):
if 'ANDROID_DATA' in os.environ:
from Crypto.Hash import RIPEMD
md = RIPEMD.new()
else:
md = hashlib.new('ripemd')
md.update(sha256(public_key))
return md.digest()
def public_key_to_bc_address(public_key):
h160 = hash_160(public_key)
return hash_160_to_bc_address(h160)
def hash_160_to_bc_address(h160, addrtype = 0):
vh160 = chr(addrtype) + h160
h = Hash(vh160)
addr = vh160 + h[0:4]
return base_encode(addr, base=58)
def bc_address_to_hash_160(addr):
bytes = base_decode(addr, 25, base=58)
return ord(bytes[0]), bytes[1:21]
__b58chars = '123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz'
assert len(__b58chars) == 58
__b43chars = '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ$*+-./:'
assert len(__b43chars) == 43
def base_encode(v, base):
""" encode v, which is a string of bytes, to base58."""
if base == 58:
chars = __b58chars
elif base == 43:
chars = __b43chars
long_value = 0L
for (i, c) in enumerate(v[::-1]):
long_value += (256**i) * ord(c)
result = ''
while long_value >= base:
div, mod = divmod(long_value, base)
result = chars[mod] + result
long_value = div
result = chars[long_value] + result
# Bitcoin does a little leading-zero-compression:
# leading 0-bytes in the input become leading-1s
nPad = 0
for c in v:
if c == '\0': nPad += 1
else: break
return (chars[0]*nPad) + result
def base_decode(v, length, base):
""" decode v into a string of len bytes."""
if base == 58:
chars = __b58chars
elif base == 43:
chars = __b43chars
long_value = 0L
for (i, c) in enumerate(v[::-1]):
long_value += chars.find(c) * (base**i)
result = ''
while long_value >= 256:
div, mod = divmod(long_value, 256)
result = chr(mod) + result
long_value = div
result = chr(long_value) + result
nPad = 0
for c in v:
if c == chars[0]: nPad += 1
else: break
result = chr(0)*nPad + result
if length is not None and len(result) != length:
return None
return result
def EncodeBase58Check(vchIn):
hash = Hash(vchIn)
return base_encode(vchIn + hash[0:4], base=58)
def DecodeBase58Check(psz):
vchRet = base_decode(psz, None, base=58)
key = vchRet[0:-4]
csum = vchRet[-4:]
hash = Hash(key)
cs32 = hash[0:4]
if cs32 != csum:
return None
else:
return key
def PrivKeyToSecret(privkey):
return privkey[9:9+32]
def SecretToASecret(secret, compressed=False, addrtype=0):
vchIn = chr((addrtype+128)&255) + secret
if compressed: vchIn += '\01'
return EncodeBase58Check(vchIn)
def ASecretToSecret(key, addrtype=0):
vch = DecodeBase58Check(key)
if vch and vch[0] == chr((addrtype+128)&255):
return vch[1:]
elif is_minikey(key):
return minikey_to_private_key(key)
else:
return False
def regenerate_key(sec):
b = ASecretToSecret(sec)
if not b:
return False
b = b[0:32]
return EC_KEY(b)
def GetPubKey(pubkey, compressed=False):
return i2o_ECPublicKey(pubkey, compressed)
def GetSecret(pkey):
return ('%064x' % pkey.secret).decode('hex')
def is_compressed(sec):
b = ASecretToSecret(sec)
return len(b) == 33
def public_key_from_private_key(sec):
# rebuild public key from private key, compressed or uncompressed
pkey = regenerate_key(sec)
assert pkey
compressed = is_compressed(sec)
public_key = GetPubKey(pkey.pubkey, compressed)
return public_key.encode('hex')
def address_from_private_key(sec):
public_key = public_key_from_private_key(sec)
address = public_key_to_bc_address(public_key.decode('hex'))
return address
def is_valid(addr):
return is_address(addr)
def is_address(addr):
ADDRESS_RE = re.compile('[1-9A-HJ-NP-Za-km-z]{26,}\\Z')
if not ADDRESS_RE.match(addr):
return False
try:
addrtype, h = bc_address_to_hash_160(addr)
except Exception:
return False
if addrtype not in [0, 5]:
return False
return addr == hash_160_to_bc_address(h, addrtype)
def is_private_key(key):
try:
k = ASecretToSecret(key)
return k is not False
except:
return False
########### end pywallet functions #######################
def is_minikey(text):
# Minikeys are typically 22 or 30 characters, but this routine
# permits any length of 20 or more provided the minikey is valid.
# A valid minikey must begin with an 'S', be in base58, and when
# suffixed with '?' have its SHA256 hash begin with a zero byte.
# They are widely used in Casascius physical bitoins.
return (len(text) >= 20 and text[0] == 'S'
and all(c in __b58chars for c in text)
and ord(sha256(text + '?')[0]) == 0)
def minikey_to_private_key(text):
return sha256(text)
from ecdsa.ecdsa import curve_secp256k1, generator_secp256k1
from ecdsa.curves import SECP256k1
from ecdsa.ellipticcurve import Point
from ecdsa.util import string_to_number, number_to_string
def msg_magic(message):
varint = var_int(len(message))
encoded_varint = "".join([chr(int(varint[i:i+2], 16)) for i in xrange(0, len(varint), 2)])
return "\x18Bitcoin Signed Message:\n" + encoded_varint + message
def verify_message(address, sig, message):
try:
public_key, compressed = pubkey_from_signature(sig, message)
# check public key using the address
pubkey = point_to_ser(public_key.pubkey.point, compressed)
addr = public_key_to_bc_address(pubkey)
if address != addr:
raise Exception("Bad signature")
# check message
h = Hash(msg_magic(message))
public_key.verify_digest(sig[1:], h, sigdecode = ecdsa.util.sigdecode_string)
return True
except Exception as e:
print_error("Verification error: {0}".format(e))
return False
def encrypt_message(message, pubkey):
return EC_KEY.encrypt_message(message, pubkey.decode('hex'))
def chunks(l, n):
return [l[i:i+n] for i in xrange(0, len(l), n)]
def ECC_YfromX(x,curved=curve_secp256k1, odd=True):
_p = curved.p()
_a = curved.a()
_b = curved.b()
for offset in range(128):
Mx = x + offset
My2 = pow(Mx, 3, _p) + _a * pow(Mx, 2, _p) + _b % _p
My = pow(My2, (_p+1)/4, _p )
if curved.contains_point(Mx,My):
if odd == bool(My&1):
return [My,offset]
return [_p-My,offset]
raise Exception('ECC_YfromX: No Y found')
def negative_point(P):
return Point( P.curve(), P.x(), -P.y(), P.order() )
def point_to_ser(P, comp=True ):
if comp:
return ( ('%02x'%(2+(P.y()&1)))+('%064x'%P.x()) ).decode('hex')
return ( '04'+('%064x'%P.x())+('%064x'%P.y()) ).decode('hex')
def ser_to_point(Aser):
curve = curve_secp256k1
generator = generator_secp256k1
_r = generator.order()
assert Aser[0] in ['\x02','\x03','\x04']
if Aser[0] == '\x04':
return Point( curve, string_to_number(Aser[1:33]), string_to_number(Aser[33:]), _r )
Mx = string_to_number(Aser[1:])
return Point( curve, Mx, ECC_YfromX(Mx, curve, Aser[0]=='\x03')[0], _r )
class MyVerifyingKey(ecdsa.VerifyingKey):
@classmethod
def from_signature(klass, sig, recid, h, curve):
""" See http://www.secg.org/download/aid-780/sec1-v2.pdf, chapter 4.1.6 """
from ecdsa import util, numbertheory
import msqr
curveFp = curve.curve
G = curve.generator
order = G.order()
# extract r,s from signature
r, s = util.sigdecode_string(sig, order)
# 1.1
x = r + (recid/2) * order
# 1.3
alpha = ( x * x * x + curveFp.a() * x + curveFp.b() ) % curveFp.p()
beta = msqr.modular_sqrt(alpha, curveFp.p())
y = beta if (beta - recid) % 2 == 0 else curveFp.p() - beta
# 1.4 the constructor checks that nR is at infinity
R = Point(curveFp, x, y, order)
# 1.5 compute e from message:
e = string_to_number(h)
minus_e = -e % order
# 1.6 compute Q = r^-1 (sR - eG)
inv_r = numbertheory.inverse_mod(r,order)
Q = inv_r * ( s * R + minus_e * G )
return klass.from_public_point( Q, curve )
def pubkey_from_signature(sig, message):
if len(sig) != 65:
raise Exception("Wrong encoding")
nV = ord(sig[0])
if nV < 27 or nV >= 35:
raise Exception("Bad encoding")
if nV >= 31:
compressed = True
nV -= 4
else:
compressed = False
recid = nV - 27
h = Hash(msg_magic(message))
return MyVerifyingKey.from_signature(sig[1:], recid, h, curve = SECP256k1), compressed
class MySigningKey(ecdsa.SigningKey):
"""Enforce low S values in signatures"""
def sign_number(self, number, entropy=None, k=None):
curve = SECP256k1
G = curve.generator
order = G.order()
r, s = ecdsa.SigningKey.sign_number(self, number, entropy, k)
if s > order/2:
s = order - s
return r, s
class EC_KEY(object):
def __init__( self, k ):
secret = string_to_number(k)
self.pubkey = ecdsa.ecdsa.Public_key( generator_secp256k1, generator_secp256k1 * secret )
self.privkey = ecdsa.ecdsa.Private_key( self.pubkey, secret )
self.secret = secret
def get_public_key(self, compressed=True):
return point_to_ser(self.pubkey.point, compressed).encode('hex')
def sign(self, msg_hash):
private_key = MySigningKey.from_secret_exponent(self.secret, curve = SECP256k1)
public_key = private_key.get_verifying_key()
signature = private_key.sign_digest_deterministic(msg_hash, hashfunc=hashlib.sha256, sigencode = ecdsa.util.sigencode_string)
assert public_key.verify_digest(signature, msg_hash, sigdecode = ecdsa.util.sigdecode_string)
return signature
def sign_message(self, message, is_compressed):
signature = self.sign(Hash(msg_magic(message)))
for i in range(4):
sig = chr(27 + i + (4 if is_compressed else 0)) + signature
try:
self.verify_message(sig, message)
return sig
except Exception:
continue
else:
raise Exception("error: cannot sign message")
def verify_message(self, sig, message):
public_key, compressed = pubkey_from_signature(sig, message)
# check public key
if point_to_ser(public_key.pubkey.point, compressed) != point_to_ser(self.pubkey.point, compressed):
raise Exception("Bad signature")
# check message
h = Hash(msg_magic(message))
public_key.verify_digest(sig[1:], h, sigdecode = ecdsa.util.sigdecode_string)
# ECIES encryption/decryption methods; AES-128-CBC with PKCS7 is used as the cipher; hmac-sha256 is used as the mac
@classmethod
def encrypt_message(self, message, pubkey):
pk = ser_to_point(pubkey)
if not ecdsa.ecdsa.point_is_valid(generator_secp256k1, pk.x(), pk.y()):
raise Exception('invalid pubkey')
ephemeral_exponent = number_to_string(ecdsa.util.randrange(pow(2,256)), generator_secp256k1.order())
ephemeral = EC_KEY(ephemeral_exponent)
ecdh_key = point_to_ser(pk * ephemeral.privkey.secret_multiplier)
key = hashlib.sha512(ecdh_key).digest()
iv, key_e, key_m = key[0:16], key[16:32], key[32:]
ciphertext = aes_encrypt_with_iv(key_e, iv, message)
ephemeral_pubkey = ephemeral.get_public_key(compressed=True).decode('hex')
encrypted = 'BIE1' + ephemeral_pubkey + ciphertext
mac = hmac.new(key_m, encrypted, hashlib.sha256).digest()
return base64.b64encode(encrypted + mac)
def decrypt_message(self, encrypted):
encrypted = base64.b64decode(encrypted)
if len(encrypted) < 85:
raise Exception('invalid ciphertext: length')
magic = encrypted[:4]
ephemeral_pubkey = encrypted[4:37]
ciphertext = encrypted[37:-32]
mac = encrypted[-32:]
if magic != 'BIE1':
raise Exception('invalid ciphertext: invalid magic bytes')
try:
ephemeral_pubkey = ser_to_point(ephemeral_pubkey)
except AssertionError, e:
raise Exception('invalid ciphertext: invalid ephemeral pubkey')
if not ecdsa.ecdsa.point_is_valid(generator_secp256k1, ephemeral_pubkey.x(), ephemeral_pubkey.y()):
raise Exception('invalid ciphertext: invalid ephemeral pubkey')
ecdh_key = point_to_ser(ephemeral_pubkey * self.privkey.secret_multiplier)
key = hashlib.sha512(ecdh_key).digest()
iv, key_e, key_m = key[0:16], key[16:32], key[32:]
if mac != hmac.new(key_m, encrypted[:-32], hashlib.sha256).digest():
raise Exception('invalid ciphertext: invalid mac')
return aes_decrypt_with_iv(key_e, iv, ciphertext)
###################################### BIP32 ##############################
random_seed = lambda n: "%032x"%ecdsa.util.randrange( pow(2,n) )
BIP32_PRIME = 0x80000000
def get_pubkeys_from_secret(secret):
# public key
private_key = ecdsa.SigningKey.from_string( secret, curve = SECP256k1 )
public_key = private_key.get_verifying_key()
K = public_key.to_string()
K_compressed = GetPubKey(public_key.pubkey,True)
return K, K_compressed
# Child private key derivation function (from master private key)
# k = master private key (32 bytes)
# c = master chain code (extra entropy for key derivation) (32 bytes)
# n = the index of the key we want to derive. (only 32 bits will be used)
# If n is negative (i.e. the 32nd bit is set), the resulting private key's
# corresponding public key can NOT be determined without the master private key.
# However, if n is positive, the resulting private key's corresponding
# public key can be determined without the master private key.
def CKD_priv(k, c, n):
is_prime = n & BIP32_PRIME
return _CKD_priv(k, c, rev_hex(int_to_hex(n,4)).decode('hex'), is_prime)
def _CKD_priv(k, c, s, is_prime):
order = generator_secp256k1.order()
keypair = EC_KEY(k)
cK = GetPubKey(keypair.pubkey,True)
data = chr(0) + k + s if is_prime else cK + s
I = hmac.new(c, data, hashlib.sha512).digest()
k_n = number_to_string( (string_to_number(I[0:32]) + string_to_number(k)) % order , order )
c_n = I[32:]
return k_n, c_n
# Child public key derivation function (from public key only)
# K = master public key
# c = master chain code
# n = index of key we want to derive
# This function allows us to find the nth public key, as long as n is
# non-negative. If n is negative, we need the master private key to find it.
def CKD_pub(cK, c, n):
if n & BIP32_PRIME: raise
return _CKD_pub(cK, c, rev_hex(int_to_hex(n,4)).decode('hex'))
# helper function, callable with arbitrary string
def _CKD_pub(cK, c, s):
order = generator_secp256k1.order()
I = hmac.new(c, cK + s, hashlib.sha512).digest()
curve = SECP256k1
pubkey_point = string_to_number(I[0:32])*curve.generator + ser_to_point(cK)
public_key = ecdsa.VerifyingKey.from_public_point( pubkey_point, curve = SECP256k1 )
c_n = I[32:]
cK_n = GetPubKey(public_key.pubkey,True)
return cK_n, c_n
BITCOIN_HEADER_PRIV = "0488ade4"
BITCOIN_HEADER_PUB = "0488b21e"
TESTNET_HEADER_PRIV = "04358394"
TESTNET_HEADER_PUB = "043587cf"
BITCOIN_HEADERS = (BITCOIN_HEADER_PUB, BITCOIN_HEADER_PRIV)
TESTNET_HEADERS = (TESTNET_HEADER_PUB, TESTNET_HEADER_PRIV)
def _get_headers(testnet):
"""Returns the correct headers for either testnet or bitcoin, in the form
of a 2-tuple, like (public, private)."""
if testnet:
return TESTNET_HEADERS
else:
return BITCOIN_HEADERS
def deserialize_xkey(xkey):
xkey = DecodeBase58Check(xkey)
assert len(xkey) == 78
xkey_header = xkey[0:4].encode('hex')
# Determine if the key is a bitcoin key or a testnet key.
if xkey_header in TESTNET_HEADERS:
head = TESTNET_HEADER_PRIV
elif xkey_header in BITCOIN_HEADERS:
head = BITCOIN_HEADER_PRIV
else:
raise Exception("Unknown xkey header: '%s'" % xkey_header)
depth = ord(xkey[4])
fingerprint = xkey[5:9]
child_number = xkey[9:13]
c = xkey[13:13+32]
if xkey[0:4].encode('hex') == head:
K_or_k = xkey[13+33:]
else:
K_or_k = xkey[13+32:]
return depth, fingerprint, child_number, c, K_or_k
def get_xkey_name(xkey, testnet=False):
depth, fingerprint, child_number, c, K = deserialize_xkey(xkey)
n = int(child_number.encode('hex'), 16)
if n & BIP32_PRIME:
child_id = "%d'"%(n - BIP32_PRIME)
else:
child_id = "%d"%n
if depth == 0:
return ''
elif depth == 1:
return child_id
else:
raise BaseException("xpub depth error")
def xpub_from_xprv(xprv, testnet=False):
depth, fingerprint, child_number, c, k = deserialize_xkey(xprv)
K, cK = get_pubkeys_from_secret(k)
header_pub, _ = _get_headers(testnet)
xpub = header_pub.decode('hex') + chr(depth) + fingerprint + child_number + c + cK
return EncodeBase58Check(xpub)
def bip32_root(seed, testnet=False):
header_pub, header_priv = _get_headers(testnet)
I = hmac.new("Bitcoin seed", seed, hashlib.sha512).digest()
master_k = I[0:32]
master_c = I[32:]
K, cK = get_pubkeys_from_secret(master_k)
xprv = (header_priv + "00" + "00000000" + "00000000").decode("hex") + master_c + chr(0) + master_k
xpub = (header_pub + "00" + "00000000" + "00000000").decode("hex") + master_c + cK
return EncodeBase58Check(xprv), EncodeBase58Check(xpub)
def xpub_from_pubkey(cK, testnet=False):
header_pub, header_priv = _get_headers(testnet)
assert cK[0] in ['\x02','\x03']
master_c = chr(0)*32
xpub = (header_pub + "00" + "00000000" + "00000000").decode("hex") + master_c + cK
return EncodeBase58Check(xpub)
def bip32_private_derivation(xprv, branch, sequence, testnet=False):
assert sequence.startswith(branch)
if branch == sequence:
return xprv, xpub_from_xprv(xprv, testnet)
header_pub, header_priv = _get_headers(testnet)
depth, fingerprint, child_number, c, k = deserialize_xkey(xprv)
sequence = sequence[len(branch):]
for n in sequence.split('/'):
if n == '': continue
i = int(n[:-1]) + BIP32_PRIME if n[-1] == "'" else int(n)
parent_k = k
k, c = CKD_priv(k, c, i)
depth += 1
_, parent_cK = get_pubkeys_from_secret(parent_k)
fingerprint = hash_160(parent_cK)[0:4]
child_number = ("%08X"%i).decode('hex')
K, cK = get_pubkeys_from_secret(k)
xprv = header_priv.decode('hex') + chr(depth) + fingerprint + child_number + c + chr(0) + k
xpub = header_pub.decode('hex') + chr(depth) + fingerprint + child_number + c + cK
return EncodeBase58Check(xprv), EncodeBase58Check(xpub)
def bip32_public_derivation(xpub, branch, sequence, testnet=False):
header_pub, _ = _get_headers(testnet)
depth, fingerprint, child_number, c, cK = deserialize_xkey(xpub)
assert sequence.startswith(branch)
sequence = sequence[len(branch):]
for n in sequence.split('/'):
if n == '': continue
i = int(n)
parent_cK = cK
cK, c = CKD_pub(cK, c, i)
depth += 1
fingerprint = hash_160(parent_cK)[0:4]
child_number = ("%08X"%i).decode('hex')
xpub = header_pub.decode('hex') + chr(depth) + fingerprint + child_number + c + cK
return EncodeBase58Check(xpub)
def bip32_private_key(sequence, k, chain):
for i in sequence:
k, chain = CKD_priv(k, chain, i)
return SecretToASecret(k, True)
def xkeys_from_seed(seed, passphrase, derivation):
from mnemonic import Mnemonic
xprv, xpub = bip32_root(Mnemonic.mnemonic_to_seed(seed, passphrase))
xprv, xpub = bip32_private_derivation(xprv, "m/", derivation)
return xprv, xpub