def get_signatures_from_script(script):
"""Returns a list of signatures retrieved from the provided (partially)
signed multisig scriptSig.
:param script: The partially-signed multisig scriptSig.
:type script: ``bytes``
:returns: A list of retrieved signature from the provided scriptSig.
:rtype: A ``list`` of ``bytes`` signatures
"""
script = script[1:] # remove the first OP_0
sigs = []
while len(script) > 0:
# Consume script while extracting possible signatures:
val, script = read_var_int(script)
potential_sig, script = read_bytes(script, val)
try:
# Raises ValueError if argument to `der_to_cdata` is not a
# DER-encoding of a signature (without the appended SIGHASH).
der_to_cdata(potential_sig[:-1])
# We only add if DER-encoded signature:
sigs.append(potential_sig)
except ValueError:
pass
return sigs
def verify(self, signature, message, hasher=sha256):
msg_hash = hasher(message) if hasher is not None else message
if len(msg_hash) != 32:
raise ValueError('Message hash must be 32 bytes long.')
verified = lib.secp256k1_ecdsa_verify(self.context.ctx, der_to_cdata(signature), msg_hash, self.public_key)
# A performance hack to avoid global bool() lookup.
return not not verified
def verify(self,
signature: bytes,
message: bytes,
hasher: Hasher = sha256) -> bool:
"""
:param signature: The ECDSA signature.
:param message: The message that was supposedly signed.
:param hasher: The hash function to use, which must return 32 bytes. By default,
the `sha256` algorithm is used. If `None`, no hashing occurs.
:return: A boolean indicating whether or not the signature is correct.
:raises ValueError: If the message hash was not 32 bytes long or the DER-encoded signature could not be parsed.
"""
msg_hash = hasher(message) if hasher is not None else message
if len(msg_hash) != 32:
raise ValueError('Message hash must be 32 bytes long.')
verified = lib.secp256k1_ecdsa_verify(self.context.ctx,
der_to_cdata(signature),
msg_hash, self.public_key)
# A performance hack to avoid global bool() lookup.
return not not verified
def test_der():
assert cdata_to_der(der_to_cdata(SIGNATURE)) == SIGNATURE
def sign_message(self, msg_bytes):
# check if ledger wallet
sig = self._pk.sign(msg_bytes)
return serialize_compact(raw_sig=der_to_cdata(der=sig))
