lukechilds
/
electrum
mirror of https://github.com/lukechilds/electrum.git
1
0
Fork 0
Code Issues Projects Releases Wiki Activity
You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
9209 Commits
21 Branches
132 Tags
52 MiB
 
 
 
 
Tree: 7dfd3c4f7f
Branches Tags
${ item.name }
Create tag ${ searchTerm }
Create branch ${ searchTerm }
from '7dfd3c4f7f'
${ noResults }
electrum/lib/bitcoin.py

761 lines
24 KiB
Raw Blame History

# -*- coding: utf-8 -*-
#
# 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 hmac
from .util import bfh, bh2u, BitcoinException, print_error, assert_bytes, to_bytes, inv_dict
from . import version
from . import segwit_addr
from . import constants
from . import ecc
from .crypto import Hash, sha256, hash_160, hmac_oneshot
################################## transactions
COINBASE_MATURITY = 100
COIN = 100000000
TOTAL_COIN_SUPPLY_LIMIT_IN_BTC = 21000000
# supported types of transaction outputs
TYPE_ADDRESS = 0
TYPE_PUBKEY = 1
TYPE_SCRIPT = 2
def rev_hex(s):
return bh2u(bfh(s)[::-1])
def int_to_hex(i: int, length: int=1) -> str:
"""Converts int to little-endian hex string.
`length` is the number of bytes available
"""
if not isinstance(i, int):
raise TypeError('{} instead of int'.format(i))
range_size = pow(256, length)
if i < -range_size/2 or i >= range_size:
raise OverflowError('cannot convert int {} to hex ({} bytes)'.format(i, length))
if i < 0:
# two's complement
i = range_size + i
s = hex(i)[2:].rstrip('L')
s = "0"*(2*length - len(s)) + s
return rev_hex(s)
def script_num_to_hex(i: int) -> str:
"""See CScriptNum in Bitcoin Core.
Encodes an integer as hex, to be used in script.
ported from https://github.com/bitcoin/bitcoin/blob/8cbc5c4be4be22aca228074f087a374a7ec38be8/src/script/script.h#L326
"""
if i == 0:
return ''
result = bytearray()
neg = i < 0
absvalue = abs(i)
while absvalue > 0:
result.append(absvalue & 0xff)
absvalue >>= 8
if result[-1] & 0x80:
result.append(0x80 if neg else 0x00)
elif neg:
result[-1] |= 0x80
return bh2u(result)
def var_int(i: int) -> str:
# 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 witness_push(item: str) -> str:
"""Returns data in the form it should be present in the witness.
hex -> hex
"""
return var_int(len(item) // 2) + item
def op_push(i: int) -> str:
if i<0x4c: # OP_PUSHDATA1
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 push_script(data: str) -> str:
"""Returns pushed data to the script, automatically
choosing canonical opcodes depending on the length of the data.
hex -> hex
ported from https://github.com/btcsuite/btcd/blob/fdc2bc867bda6b351191b5872d2da8270df00d13/txscript/scriptbuilder.go#L128
"""
data = bfh(data)
from .transaction import opcodes
data_len = len(data)
# "small integer" opcodes
if data_len == 0 or data_len == 1 and data[0] == 0:
return bh2u(bytes([opcodes.OP_0]))
elif data_len == 1 and data[0] <= 16:
return bh2u(bytes([opcodes.OP_1 - 1 + data[0]]))
elif data_len == 1 and data[0] == 0x81:
return bh2u(bytes([opcodes.OP_1NEGATE]))
return op_push(data_len) + bh2u(data)
def add_number_to_script(i: int) -> bytes:
return bfh(push_script(script_num_to_hex(i)))
hash_encode = lambda x: bh2u(x[::-1])
hash_decode = lambda x: bfh(x)[::-1]
hmac_sha_512 = lambda x, y: hmac_oneshot(x, y, hashlib.sha512)
def is_new_seed(x, prefix=version.SEED_PREFIX):
from . import mnemonic
x = mnemonic.normalize_text(x)
s = bh2u(hmac_sha_512(b"Seed version", x.encode('utf8')))
return s.startswith(prefix)
def is_old_seed(seed):
from . import old_mnemonic, mnemonic
seed = mnemonic.normalize_text(seed)
words = seed.split()
try:
# checks here are deliberately left weak for legacy reasons, see #3149
old_mnemonic.mn_decode(words)
uses_electrum_words = True
except Exception:
uses_electrum_words = False
try:
seed = bfh(seed)
is_hex = (len(seed) == 16 or len(seed) == 32)
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_SW):
return 'segwit'
elif is_new_seed(x, version.SEED_PREFIX_2FA):
return '2fa'
return ''
is_seed = lambda x: bool(seed_type(x))
############ functions from pywallet #####################
def hash160_to_b58_address(h160: bytes, addrtype):
s = bytes([addrtype])
s += h160
return base_encode(s+Hash(s)[0:4], base=58)
def b58_address_to_hash160(addr):
addr = to_bytes(addr, 'ascii')
_bytes = base_decode(addr, 25, base=58)
return _bytes[0], _bytes[1:21]
def hash160_to_p2pkh(h160, *, net=None):
if net is None:
net = constants.net
return hash160_to_b58_address(h160, net.ADDRTYPE_P2PKH)
def hash160_to_p2sh(h160, *, net=None):
if net is None:
net = constants.net
return hash160_to_b58_address(h160, net.ADDRTYPE_P2SH)
def public_key_to_p2pkh(public_key: bytes) -> str:
return hash160_to_p2pkh(hash_160(public_key))
def hash_to_segwit_addr(h, witver, *, net=None):
if net is None:
net = constants.net
return segwit_addr.encode(net.SEGWIT_HRP, witver, h)
def public_key_to_p2wpkh(public_key):
return hash_to_segwit_addr(hash_160(public_key), witver=0)
def script_to_p2wsh(script):
return hash_to_segwit_addr(sha256(bfh(script)), witver=0)
def p2wpkh_nested_script(pubkey):
pkh = bh2u(hash_160(bfh(pubkey)))
return '00' + push_script(pkh)
def p2wsh_nested_script(witness_script):
wsh = bh2u(sha256(bfh(witness_script)))
return '00' + push_script(wsh)
def pubkey_to_address(txin_type, pubkey):
if txin_type == 'p2pkh':
return public_key_to_p2pkh(bfh(pubkey))
elif txin_type == 'p2wpkh':
return public_key_to_p2wpkh(bfh(pubkey))
elif txin_type == 'p2wpkh-p2sh':
scriptSig = p2wpkh_nested_script(pubkey)
return hash160_to_p2sh(hash_160(bfh(scriptSig)))
else:
raise NotImplementedError(txin_type)
def redeem_script_to_address(txin_type, redeem_script):
if txin_type == 'p2sh':
return hash160_to_p2sh(hash_160(bfh(redeem_script)))
elif txin_type == 'p2wsh':
return script_to_p2wsh(redeem_script)
elif txin_type == 'p2wsh-p2sh':
scriptSig = p2wsh_nested_script(redeem_script)
return hash160_to_p2sh(hash_160(bfh(scriptSig)))
else:
raise NotImplementedError(txin_type)
def script_to_address(script, *, net=None):
from .transaction import get_address_from_output_script
t, addr = get_address_from_output_script(bfh(script), net=net)
assert t == TYPE_ADDRESS
return addr
def address_to_script(addr, *, net=None):
if net is None:
net = constants.net
witver, witprog = segwit_addr.decode(net.SEGWIT_HRP, addr)
if witprog is not None:
if not (0 <= witver <= 16):
raise BitcoinException('impossible witness version: {}'.format(witver))
OP_n = witver + 0x50 if witver > 0 else 0
script = bh2u(bytes([OP_n]))
script += push_script(bh2u(bytes(witprog)))
return script
addrtype, hash_160 = b58_address_to_hash160(addr)
if addrtype == net.ADDRTYPE_P2PKH:
script = '76a9' # op_dup, op_hash_160
script += push_script(bh2u(hash_160))
script += '88ac' # op_equalverify, op_checksig
elif addrtype == net.ADDRTYPE_P2SH:
script = 'a9' # op_hash_160
script += push_script(bh2u(hash_160))
script += '87' # op_equal
else:
raise BitcoinException('unknown address type: {}'.format(addrtype))
return script
def address_to_scripthash(addr):
script = address_to_script(addr)
return script_to_scripthash(script)
def script_to_scripthash(script):
h = sha256(bytes.fromhex(script))[0:32]
return bh2u(bytes(reversed(h)))
def public_key_to_p2pk_script(pubkey):
script = push_script(pubkey)
script += 'ac' # op_checksig
return script
__b58chars = b'123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz'
assert len(__b58chars) == 58
__b43chars = b'0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ$*+-./:'
assert len(__b43chars) == 43
def base_encode(v: bytes, base: int) -> str:
""" encode v, which is a string of bytes, to base58."""
assert_bytes(v)
if base not in (58, 43):
raise ValueError('not supported base: {}'.format(base))
chars = __b58chars
if base == 43:
chars = __b43chars
long_value = 0
for (i, c) in enumerate(v[::-1]):
long_value += (256**i) * c
result = bytearray()
while long_value >= base:
div, mod = divmod(long_value, base)
result.append(chars[mod])
long_value = div
result.append(chars[long_value])
# Bitcoin does a little leading-zero-compression:
# leading 0-bytes in the input become leading-1s
nPad = 0
for c in v:
if c == 0x00:
nPad += 1
else:
break
result.extend([chars[0]] * nPad)
result.reverse()
return result.decode('ascii')
def base_decode(v, length, base):
""" decode v into a string of len bytes."""
# assert_bytes(v)
v = to_bytes(v, 'ascii')
if base not in (58, 43):
raise ValueError('not supported base: {}'.format(base))
chars = __b58chars
if base == 43:
chars = __b43chars
long_value = 0
for (i, c) in enumerate(v[::-1]):
digit = chars.find(bytes([c]))
if digit == -1:
raise ValueError('Forbidden character {} for base {}'.format(c, base))
long_value += digit * (base**i)
result = bytearray()
while long_value >= 256:
div, mod = divmod(long_value, 256)
result.append(mod)
long_value = div
result.append(long_value)
nPad = 0
for c in v:
if c == chars[0]:
nPad += 1
else:
break
result.extend(b'\x00' * nPad)
if length is not None and len(result) != length:
return None
result.reverse()
return bytes(result)
class InvalidChecksum(Exception):
pass
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:
raise InvalidChecksum('expected {}, actual {}'.format(bh2u(cs32), bh2u(csum)))
else:
return key
# backwards compat
# extended WIF for segwit (used in 3.0.x; but still used internally)
# the keys in this dict should be a superset of what Imported Wallets can import
WIF_SCRIPT_TYPES = {
'p2pkh':0,
'p2wpkh':1,
'p2wpkh-p2sh':2,
'p2sh':5,
'p2wsh':6,
'p2wsh-p2sh':7
}
WIF_SCRIPT_TYPES_INV = inv_dict(WIF_SCRIPT_TYPES)
PURPOSE48_SCRIPT_TYPES = {
'p2wsh-p2sh': 1, # specifically multisig
'p2wsh': 2, # specifically multisig
}
PURPOSE48_SCRIPT_TYPES_INV = inv_dict(PURPOSE48_SCRIPT_TYPES)
def serialize_privkey(secret: bytes, compressed: bool, txin_type: str,
internal_use: bool=False) -> str:
# we only export secrets inside curve range
secret = ecc.ECPrivkey.normalize_secret_bytes(secret)
if internal_use:
prefix = bytes([(WIF_SCRIPT_TYPES[txin_type] + constants.net.WIF_PREFIX) & 255])
else:
prefix = bytes([constants.net.WIF_PREFIX])
suffix = b'\01' if compressed else b''
vchIn = prefix + secret + suffix
base58_wif = EncodeBase58Check(vchIn)
if internal_use:
return base58_wif
else:
return '{}:{}'.format(txin_type, base58_wif)
def deserialize_privkey(key: str) -> (str, bytes, bool):
if is_minikey(key):
return 'p2pkh', minikey_to_private_key(key), False
txin_type = None
if ':' in key:
txin_type, key = key.split(sep=':', maxsplit=1)
if txin_type not in WIF_SCRIPT_TYPES:
raise BitcoinException('unknown script type: {}'.format(txin_type))
try:
vch = DecodeBase58Check(key)
except BaseException:
neutered_privkey = str(key)[:3] + '..' + str(key)[-2:]
raise BitcoinException("cannot deserialize privkey {}"
.format(neutered_privkey))
if txin_type is None:
# keys exported in version 3.0.x encoded script type in first byte
prefix_value = vch[0] - constants.net.WIF_PREFIX
try:
txin_type = WIF_SCRIPT_TYPES_INV[prefix_value]
except KeyError:
raise BitcoinException('invalid prefix ({}) for WIF key (1)'.format(vch[0]))
else:
# all other keys must have a fixed first byte
if vch[0] != constants.net.WIF_PREFIX:
raise BitcoinException('invalid prefix ({}) for WIF key (2)'.format(vch[0]))
if len(vch) not in [33, 34]:
raise BitcoinException('invalid vch len for WIF key: {}'.format(len(vch)))
compressed = len(vch) == 34
secret_bytes = vch[1:33]
# we accept secrets outside curve range; cast into range here:
secret_bytes = ecc.ECPrivkey.normalize_secret_bytes(secret_bytes)
return txin_type, secret_bytes, compressed
def is_compressed(sec):
return deserialize_privkey(sec)[2]
def address_from_private_key(sec):
txin_type, privkey, compressed = deserialize_privkey(sec)
public_key = ecc.ECPrivkey(privkey).get_public_key_hex(compressed=compressed)
return pubkey_to_address(txin_type, public_key)
def is_segwit_address(addr):
try:
witver, witprog = segwit_addr.decode(constants.net.SEGWIT_HRP, addr)
except Exception as e:
return False
return witprog is not None
def is_b58_address(addr):
try:
addrtype, h = b58_address_to_hash160(addr)
except Exception as e:
return False
if addrtype not in [constants.net.ADDRTYPE_P2PKH, constants.net.ADDRTYPE_P2SH]:
return False
return addr == hash160_to_b58_address(h, addrtype)
def is_address(addr):
return is_segwit_address(addr) or is_b58_address(addr)
def is_private_key(key):
try:
k = deserialize_privkey(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 bitcoins.
return (len(text) >= 20 and text[0] == 'S'
and all(ord(c) in __b58chars for c in text)
and sha256(text + '?')[0] == 0x00)
def minikey_to_private_key(text):
return sha256(text)
###################################### BIP32 ##############################
BIP32_PRIME = 0x80000000
def protect_against_invalid_ecpoint(func):
def func_wrapper(*args):
n = args[-1]
while True:
is_prime = n & BIP32_PRIME
try:
return func(*args[:-1], n=n)
except ecc.InvalidECPointException:
print_error('bip32 protect_against_invalid_ecpoint: skipping index')
n += 1
is_prime2 = n & BIP32_PRIME
if is_prime != is_prime2: raise OverflowError()
return func_wrapper
# 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 hardened (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 not hardened, the resulting private key's corresponding
# public key can be determined without the master private key.
@protect_against_invalid_ecpoint
def CKD_priv(k, c, n):
if n < 0: raise ValueError('the bip32 index needs to be non-negative')
is_prime = n & BIP32_PRIME
return _CKD_priv(k, c, bfh(rev_hex(int_to_hex(n,4))), is_prime)
def _CKD_priv(k, c, s, is_prime):
try:
keypair = ecc.ECPrivkey(k)
except ecc.InvalidECPointException as e:
raise BitcoinException('Impossible xprv (not within curve order)') from e
cK = keypair.get_public_key_bytes(compressed=True)
data = bytes([0]) + k + s if is_prime else cK + s
I = hmac_oneshot(c, data, hashlib.sha512)
I_left = ecc.string_to_number(I[0:32])
k_n = (I_left + ecc.string_to_number(k)) % ecc.CURVE_ORDER
if I_left >= ecc.CURVE_ORDER or k_n == 0:
raise ecc.InvalidECPointException()
k_n = ecc.number_to_string(k_n, ecc.CURVE_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
# not hardened. If n is hardened, we need the master private key to find it.
@protect_against_invalid_ecpoint
def CKD_pub(cK, c, n):
if n < 0: raise ValueError('the bip32 index needs to be non-negative')
if n & BIP32_PRIME: raise Exception()
return _CKD_pub(cK, c, bfh(rev_hex(int_to_hex(n,4))))
# helper function, callable with arbitrary string.
# note: 's' does not need to fit into 32 bits here! (c.f. trustedcoin billing)
def _CKD_pub(cK, c, s):
I = hmac_oneshot(c, cK + s, hashlib.sha512)
pubkey = ecc.ECPrivkey(I[0:32]) + ecc.ECPubkey(cK)
if pubkey.is_at_infinity():
raise ecc.InvalidECPointException()
cK_n = pubkey.get_public_key_bytes(compressed=True)
c_n = I[32:]
return cK_n, c_n
def xprv_header(xtype, *, net=None):
if net is None:
net = constants.net
return bfh("%08x" % net.XPRV_HEADERS[xtype])
def xpub_header(xtype, *, net=None):
if net is None:
net = constants.net
return bfh("%08x" % net.XPUB_HEADERS[xtype])
def serialize_xprv(xtype, c, k, depth=0, fingerprint=b'\x00'*4,
child_number=b'\x00'*4, *, net=None):
if not ecc.is_secret_within_curve_range(k):
raise BitcoinException('Impossible xprv (not within curve order)')
xprv = xprv_header(xtype, net=net) \
+ bytes([depth]) + fingerprint + child_number + c + bytes([0]) + k
return EncodeBase58Check(xprv)
def serialize_xpub(xtype, c, cK, depth=0, fingerprint=b'\x00'*4,
child_number=b'\x00'*4, *, net=None):
xpub = xpub_header(xtype, net=net) \
+ bytes([depth]) + fingerprint + child_number + c + cK
return EncodeBase58Check(xpub)
def deserialize_xkey(xkey, prv, *, net=None):
if net is None:
net = constants.net
xkey = DecodeBase58Check(xkey)
if len(xkey) != 78:
raise BitcoinException('Invalid length for extended key: {}'
.format(len(xkey)))
depth = xkey[4]
fingerprint = xkey[5:9]
child_number = xkey[9:13]
c = xkey[13:13+32]
header = int('0x' + bh2u(xkey[0:4]), 16)
headers = net.XPRV_HEADERS if prv else net.XPUB_HEADERS
if header not in headers.values():
raise BitcoinException('Invalid extended key format: {}'
.format(hex(header)))
xtype = list(headers.keys())[list(headers.values()).index(header)]
n = 33 if prv else 32
K_or_k = xkey[13+n:]
if prv and not ecc.is_secret_within_curve_range(K_or_k):
raise BitcoinException('Impossible xprv (not within curve order)')
return xtype, depth, fingerprint, child_number, c, K_or_k
def deserialize_xpub(xkey, *, net=None):
return deserialize_xkey(xkey, False, net=net)
def deserialize_xprv(xkey, *, net=None):
return deserialize_xkey(xkey, True, net=net)
def xpub_type(x):
return deserialize_xpub(x)[0]
def is_xpub(text):
try:
deserialize_xpub(text)
return True
except:
return False
def is_xprv(text):
try:
deserialize_xprv(text)
return True
except:
return False
def xpub_from_xprv(xprv):
xtype, depth, fingerprint, child_number, c, k = deserialize_xprv(xprv)
cK = ecc.ECPrivkey(k).get_public_key_bytes(compressed=True)
return serialize_xpub(xtype, c, cK, depth, fingerprint, child_number)
def bip32_root(seed, xtype):
I = hmac_oneshot(b"Bitcoin seed", seed, hashlib.sha512)
master_k = I[0:32]
master_c = I[32:]
# create xprv first, as that will check if master_k is within curve order
xprv = serialize_xprv(xtype, master_c, master_k)
cK = ecc.ECPrivkey(master_k).get_public_key_bytes(compressed=True)
xpub = serialize_xpub(xtype, master_c, cK)
return xprv, xpub
def xpub_from_pubkey(xtype, cK):
if cK[0] not in (0x02, 0x03):
raise ValueError('Unexpected first byte: {}'.format(cK[0]))
return serialize_xpub(xtype, b'\x00'*32, cK)
def bip32_derivation(s):
if not s.startswith('m/'):
raise ValueError('invalid bip32 derivation path: {}'.format(s))
s = s[2:]
for n in s.split('/'):
if n == '': continue
i = int(n[:-1]) + BIP32_PRIME if n[-1] == "'" else int(n)
yield i
def is_bip32_derivation(x):
try:
[ i for i in bip32_derivation(x)]
return True
except :
return False
def bip32_private_derivation(xprv, branch, sequence):
if not sequence.startswith(branch):
raise ValueError('incompatible branch ({}) and sequence ({})'
.format(branch, sequence))
if branch == sequence:
return xprv, xpub_from_xprv(xprv)
xtype, depth, fingerprint, child_number, c, k = deserialize_xprv(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 = ecc.ECPrivkey(parent_k).get_public_key_bytes(compressed=True)
fingerprint = hash_160(parent_cK)[0:4]
child_number = bfh("%08X"%i)
cK = ecc.ECPrivkey(k).get_public_key_bytes(compressed=True)
xpub = serialize_xpub(xtype, c, cK, depth, fingerprint, child_number)
xprv = serialize_xprv(xtype, c, k, depth, fingerprint, child_number)
return xprv, xpub
def bip32_public_derivation(xpub, branch, sequence):
xtype, depth, fingerprint, child_number, c, cK = deserialize_xpub(xpub)
if not sequence.startswith(branch):
raise ValueError('incompatible branch ({}) and sequence ({})'
.format(branch, sequence))
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 = bfh("%08X"%i)
return serialize_xpub(xtype, c, cK, depth, fingerprint, child_number)
def bip32_private_key(sequence, k, chain):
for i in sequence:
k, chain = CKD_priv(k, chain, i)
return k