def derive(self, index, hardened=False):
# TODO Is index Valid?
if index < HARDENED_START and hardened:
index += HARDENED_START
if hardened:
raise ValueError(
"Hardened derivation is not posible on HDPublicKey")
else:
key = self.to_public_key().to_bytes()
signed64 = hmac.new(self.chain, key + to_bytes(self.index, length=4),
hashlib.sha512).digest()
x, y = self.pubkey.pair
curve = utils.generator_secp256k1
point = int_from_bytes(signed64[:32]) * curve + utils.Point(
curve.curve(), x, y, curve.order())
pubkey = PublicKey((point.x(), point.y()), self.network)
chain = signed64[32:]
depth = self.depth + 1
return HDPublicKey(pubkey, chain, depth, index, self.fingerprint,
self.network)
def fromSeed(seed = None):
if seed is None:
seed = os.urandom(MIN_SEED_LEN)
if len(seed) < MIN_SEED_LEN:
raise ValueError("HDPublicKey seed must be at least 32 bytes long")
signed64 = hmac.new(HMAC_MAGIC_KEY, seed, hashlib.sha512).digest()
return HDPublicKey(pubkey = PublicKey.from_bytes(signed64[:32]), chain = signed64[32:])
def fromSeed(seed=None):
if seed is None:
seed = os.urandom(MIN_SEED_LEN)
if len(seed) < MIN_SEED_LEN:
raise ValueError("HDPublicKey seed must be at least 32 bytes long")
signed64 = hmac.new(HMAC_MAGIC_KEY, seed, hashlib.sha512).digest()
return HDPublicKey(pubkey=PublicKey.from_bytes(signed64[:32]),
chain=signed64[32:])
def from_string(b58_str):
data = utils.encoding.a2b_hashed_base58(b58_str) # TODO checksum?
chain = data[HDPublicKey.ChainCodeStart : HDPublicKey.ChainCodeEnd]
depth = int_from_bytes(data[HDPublicKey.DepthStart : HDPublicKey.DepthEnd])
index = int_from_bytes(data[HDPublicKey.ChildIndexStart : HDPublicKey.ChildIndexEnd])
parent = int_from_bytes(data[HDPublicKey.ParentFingerPrintStart : HDPublicKey.ParentFingerPrintEnd])
# The version field is used to deduce the network:
version = int_from_bytes(data[HDPublicKey.VersionStart:HDPublicKey.VersionEnd])
network = Network.get_by_field('hd_public_key', version)
pubkey = PublicKey.from_bytes(data[HDPublicKey.PublicKeyStart : HDPublicKey.PublicKeyEnd], network)
return HDPublicKey(pubkey, chain, depth, index, parent, network)
def from_string(b58_str):
data = utils.encoding.a2b_hashed_base58(b58_str) # TODO checksum?
chain = data[HDPublicKey.ChainCodeStart:HDPublicKey.ChainCodeEnd]
depth = int_from_bytes(
data[HDPublicKey.DepthStart:HDPublicKey.DepthEnd])
index = int_from_bytes(
data[HDPublicKey.ChildIndexStart:HDPublicKey.ChildIndexEnd])
parent = int_from_bytes(
data[HDPublicKey.ParentFingerPrintStart:HDPublicKey.
ParentFingerPrintEnd])
# The version field is used to deduce the network:
version = int_from_bytes(
data[HDPublicKey.VersionStart:HDPublicKey.VersionEnd])
network = Network.get_by_field('hd_public_key', version)
pubkey = PublicKey.from_bytes(
data[HDPublicKey.PublicKeyStart:HDPublicKey.PublicKeyEnd], network)
return HDPublicKey(pubkey, chain, depth, index, parent, network)
def to_public_key(self):
return PublicKey.from_private_key(self)
