def ExtendedKey(self, private=True, encoded=True):
"Return extended private or public key as string, optionally base58 encoded"
if self.public is True and private is True:
raise Exception(
"Cannot export an extended private key from a public-only deterministic key"
)
if not self.testnet:
version = param_query(NETWORK,
'hd_prv')[0] if private else param_query(
NETWORK, 'hd_pub')[0]
else:
version = EX_TEST_PRIVATE[0] if private else EX_TEST_PUBLIC[0]
depth = bytes(bytearray([self.depth]))
fpr = self.parent_fpr
child = struct.pack('>L', self.index)
chain = self.C
if self.public is True or private is False:
data = self.PublicKey()
else:
data = b'\x00' + self.PrivateKey()
raw = version + depth + fpr + child + chain + data
if not encoded:
return raw
else:
return base58.check_encode(raw)
def WalletImportFormat(self):
"Returns private key encoded for wallet import"
if self.public:
raise Exception(
"Publicly derived deterministic keys have no private half")
addressversion = param_query(
NETWORK, 'wif_version') if not self.testnet else '\xef'
raw = addressversion + self.k.to_string() + '\x01' # Always compressed
return base58.check_encode(raw)
def fromExtendedKey(xkey, public=False,encoded=True):
"""
Create a HDKey by importing from extended private or public key string
If public is True, return a public-only key regardless of input type.
"""
# Sanity checks
if encoded:
raw = base58.check_decode(xkey)
else:
raw = xkey
if len(raw) != 78:
raise ValueError("extended key format wrong length")
# Verify address version/type
version = raw[:4]
if version in param_query(NETWORK,'hd_prv'):
is_testnet = False
is_pubkey = False
elif version in EX_TEST_PRIVATE:
is_testnet = True
is_pubkey = False
elif version in param_query(NETWORK,'hd_pub'):
is_testnet = False
is_pubkey = True
elif version in EX_TEST_PUBLIC:
is_testnet = True
is_pubkey = True
else:
raise ValueError("unknown extended key version")
# Extract remaining fields
# Python 2.x compatibility
if type(raw[4]) == int:
depth = raw[4]
else:
depth = ord(raw[4])
fpr = raw[5:9]
child = struct.unpack(">L", raw[9:13])[0]
chain = raw[13:45]
secret = raw[45:78]
# Extract private key or public key point
if not is_pubkey:
secret = secret[1:]
else:
# Recover public curve point from compressed key
# Python3 FIX
lsb = secret[0] & 1 if type(secret[0]) == int else ord(secret[0]) & 1
x = string_to_int(secret[1:])
ys = (x**3+7) % FIELD_ORDER # y^2 = x^3 + 7 mod p
y = sqrt_mod(ys, FIELD_ORDER)
if y & 1 != lsb:
y = FIELD_ORDER-y
point = ecdsa.ellipticcurve.Point(SECP256k1.curve, x, y)
secret = ecdsa.VerifyingKey.from_public_point(point, curve=SECP256k1)
key = HDKey(secret=secret, chain=chain, depth=depth, index=child, fpr=fpr, public=is_pubkey, testnet=is_testnet)
if not is_pubkey and public:
key = key.SetPublic()
return key
def Address(self, ip = False):
"Return compressed public key address"
addressversion = param_query(NETWORK,'address_version') if not ip else '\x66'
vh160 = addressversion + self.Identifier()
return base58.check_encode(vh160)
def parameters(self):
'''load network parameters.'''
return param_query(self.net)