pyflo/pybtc/functions/bip32.py
2019-04-23 13:20:08 +04:00

258 lines
9.7 KiB
Python

from struct import pack
from pybtc.functions.key import private_to_public_key, private_key_to_wif
from pybtc.functions.hash import hmac_sha512, double_sha256, hash160
from pybtc.functions.encode import (encode_base58,
decode_base58_with_checksum,
encode_base58_with_checksum)
from pybtc.constants import *
from pybtc.crypto import __secp256k1_ec_pubkey_tweak_add__
def create_master_xprivate_key(seed, testnet=False, base58=True, hex=False):
"""
Create extended private key from seed
:param str,bytes key: seed HEX or bytes string.
:param boolean base58: (optional) return result as base58 encoded string, by default True.
:param boolean hex: (optional) return result as HEX encoded string, by default False.
In case True base58 flag value will be ignored.
:return: extended private key in base58, HEX or bytes string format.
"""
if isinstance(seed, str):
seed = bytes.fromhex(seed)
if not isinstance(seed, bytes):
raise TypeError("seed should be bytes or hex encoded string")
i = hmac_sha512(b"Bitcoin seed", seed)
m, c = i[:32], i[32:]
m_int = int.from_bytes(m, byteorder="big")
if m_int <= 0 or m_int > ECDSA_SEC256K1_ORDER:
return None
prefix = TESTNET_XPRIVATE_KEY_PREFIX if testnet else MAINNET_XPRIVATE_KEY_PREFIX
key = b''.join([prefix,
b'\x00\x00\x00\x00\x00\x00\x00\x00\x00',
c, b'\x00', m])
if base58:
key = b"".join([key, double_sha256(key)[:4]])
return encode_base58(key)
else:
return key if not hex else key.hex()
def xprivate_to_xpublic_key(xprivate_key, base58=True, hex=False):
"""
Get extended public key from extended private key using ECDSA secp256k1
:param str,bytes key: extended private key in base58, HEX or bytes string.
:param boolean base58: (optional) return result as base58 encoded string, by default True.
:param boolean hex: (optional) return result as HEX encoded string, by default False.
In case True base58 flag value will be ignored.
:return: extended public key in base58, HEX or bytes string format.
"""
if isinstance(xprivate_key, str):
try:
if len(xprivate_key) == 156:
xprivate_key = bytes.fromhex(xprivate_key)
else:
xprivate_key = decode_base58_with_checksum(xprivate_key)
except:
raise ValueError("invalid extended private key")
if not isinstance(xprivate_key, bytes):
raise TypeError("extended private key should be base58 string or bytes")
if xprivate_key[:4] == TESTNET_XPRIVATE_KEY_PREFIX:
prefix = TESTNET_XPUBLIC_KEY_PREFIX
elif xprivate_key[:4] == MAINNET_XPRIVATE_KEY_PREFIX:
prefix = MAINNET_XPUBLIC_KEY_PREFIX
else:
raise ValueError("invalid extended private key")
key = b"".join([prefix,
xprivate_key[4:45],
private_to_public_key(xprivate_key[46:], hex=False)])
if hex:
return key.hex()
elif base58:
key = b"".join([key, double_sha256(key)[:4]])
return encode_base58(key)
else:
return key
def derive_xkey(xkey, *path_level, base58=True, hex=False):
"""
Child Key derivation for extended private/public keys
:param bytes xkey: extended private/public in base58, HEX or bytes string format.
:param list path_level: list of derivation path levels. For hardened derivation use HARDENED_KEY flag.
:param boolean base58: (optional) return result as base58 encoded string, by default True.
:param boolean hex: (optional) return result as HEX encoded string, by default False.
In case True base58 flag value will be ignored.
:return: extended child private/public key in base58, HEX or bytes string format.
"""
xkey = decode_base58_with_checksum(xkey)
if xkey[:4] in [MAINNET_XPRIVATE_KEY_PREFIX, TESTNET_XPRIVATE_KEY_PREFIX]:
for i in path_level:
xkey = derive_child_xprivate_key(xkey, i)
elif xkey[:4] in [MAINNET_XPUBLIC_KEY_PREFIX, TESTNET_XPUBLIC_KEY_PREFIX]:
for i in path_level:
xkey = derive_child_xpublic_key(xkey, i)
else:
raise ValueError("invalid extended key")
if hex:
return xkey.hex()
elif base58:
return encode_base58_with_checksum(xkey)
else:
return xkey
def derive_child_xprivate_key(xprivate_key, i):
c = xprivate_key[13:45]
k = xprivate_key[45:]
depth = xprivate_key[4] + 1
if depth > 255:
raise ValueError("path depth should be <= 255")
pub = private_to_public_key(k[1:], hex=False)
fingerprint = hash160(pub)[:4]
s = hmac_sha512(c, b"%s%s" % (k if i >= HARDENED_KEY else pub, pack(">L", i)))
p_int = int.from_bytes(s[:32],byteorder='big')
if p_int >= ECDSA_SEC256K1_ORDER:
return None
k_int = (int.from_bytes(k[1:], byteorder='big') + p_int) % ECDSA_SEC256K1_ORDER
if not k_int:
return None
key = int.to_bytes(k_int, byteorder = "big", length=32)
return b"".join([xprivate_key[:4],
bytes([depth]),
fingerprint,
pack(">L", i),
s[32:],
b'\x00',
key])
def derive_child_xpublic_key(xpublic_key, i):
c = xpublic_key[13:45]
k = xpublic_key[45:]
fingerprint = hash160(k)[:4]
depth = xpublic_key[4] + 1
if depth > 255:
raise ValueError("path depth should be <= 255")
if i >= HARDENED_KEY:
raise ValueError("derivation from extended public key impossible")
s = hmac_sha512(c, k + pack(">L", i))
if int.from_bytes(s[:32], byteorder='big') >= ECDSA_SEC256K1_ORDER:
return None
pk = __secp256k1_ec_pubkey_tweak_add__(k, s[:32])
if isinstance(pk, int):
raise RuntimeError("pubkey_tweak_add error %s" %pk)
return b"".join([xpublic_key[:4],
bytes([depth]),
fingerprint,
pack(">L", i),
s[32:],
pk])
def public_from_xpublic_key(xpublic_key, hex=True):
"""
Get public key from extended public key
:param bytes xpublic_key: extended public in base58, HEX or bytes string format.
:param boolean base58: (optional) return result as base58 encoded string, by default True.
:param boolean hex: (optional) return result as HEX encoded string, by default False.
In case True base58 flag value will be ignored.
:return: public key in HEX or bytes string format.
"""
if isinstance(xpublic_key, str):
if len(xpublic_key) == 156:
xpublic_key = bytes.fromhex(xpublic_key)
else:
xpublic_key = decode_base58_with_checksum(xpublic_key)
if not isinstance(xpublic_key, bytes):
raise TypeError("xpublic_key should be HEX, Base58 or bytes string")
if xpublic_key[:4] not in [MAINNET_XPUBLIC_KEY_PREFIX,
TESTNET_XPUBLIC_KEY_PREFIX]:
raise ValueError("invalid extended public key")
return xpublic_key[45:].hex() if hex else xpublic_key[45:]
def private_from_xprivate_key(xprivate_key, wif=True, hex=False):
"""
Get private key from extended private key
:param bytes xprivate_key: extended public in base58, HEX or bytes string format.
:param boolean wif: (optional) return result as WIF format, by default True.
:param boolean hex: (optional) return result as HEX encoded string, by default False.
In case True WIF flag value will be ignored.
:return: private key in HEX or bytes string format.
"""
if isinstance(xprivate_key, str):
if len(xprivate_key) == 156:
xprivate_key = bytes.fromhex(xprivate_key)
else:
xprivate_key = decode_base58_with_checksum(xprivate_key)
if not isinstance(xprivate_key, bytes):
raise TypeError("xprivate_key should be HEX, Base58 or bytes string")
if xprivate_key[:4] not in [MAINNET_XPRIVATE_KEY_PREFIX,
TESTNET_XPRIVATE_KEY_PREFIX]:
raise ValueError("invalid extended private key")
if hex:
return xprivate_key[46:].hex()
elif wif:
if xprivate_key[:4] == MAINNET_XPRIVATE_KEY_PREFIX:
testnet = False
else:
testnet = True
return private_key_to_wif(xprivate_key[46:], testnet=testnet)
return xprivate_key[46:].hex() if hex else xprivate_key[46:]
def is_xprivate_key_valid(key):
"""
Check the extended private key is valid according to BIP-0032.
:param key: extended private key in BASE58, HEX or bytes string format.
:return: boolean.
"""
if isinstance(key, str):
try:
key = decode_base58_with_checksum(key)
except:
try:
key = bytes.fromhex(key)
except:
pass
if not isinstance(key, bytes) or len(key)!=78:
return False
if key[:4] not in [MAINNET_XPRIVATE_KEY_PREFIX,
TESTNET_XPRIVATE_KEY_PREFIX]:
return False
return True
def is_xpublic_key_valid(key):
"""
Check the extended private key is valid according to BIP-0032.
:param key: extended private key in BASE58, HEX or bytes string format.
:return: boolean.
"""
if isinstance(key, str):
try:
key = decode_base58_with_checksum(key)
except:
try:
key = bytes.fromhex(key)
except:
pass
if not isinstance(key, bytes) or len(key)!=78:
return False
if key[:4] not in [MAINNET_XPUBLIC_KEY_PREFIX,
TESTNET_XPUBLIC_KEY_PREFIX]:
return False
return True