def test_signature_recoverable(self):
private_key = PrivateKey(PRIVATE_KEY_BYTES)
assert (private_key.public_key.format() == PublicKey(
recover(
MESSAGE,
deserialize_recoverable(
private_key.sign_recoverable(MESSAGE)))).format())
def from_signature_and_message(cls,
serialized_sig,
message,
hasher=sha256,
context=GLOBAL_CONTEXT):
return PublicKey(
recover(message,
deserialize_recoverable(serialized_sig, context=context),
hasher=hasher,
context=context))
def from_signature_and_message(cls,
signature: bytes,
message: bytes,
hasher: Hasher = sha256,
context: Context = GLOBAL_CONTEXT):
"""
Recover an ECDSA public key from a recoverable signature.
:param signature: The recoverable 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.
:param context:
:return: The public key that signed the message.
:rtype: PublicKey
:raises ValueError: If the message hash was not 32 bytes long or recovery of the ECDSA public key failed.
"""
return PublicKey(
recover(message,
deserialize_recoverable(signature, context=context),
hasher=hasher,
context=context))