def sign(message: object, private_key: str) -> str:
"""
signs a message
@param message: (object) message to sign
@param private_key: (str) private key to sign with
"""
private_key_bytes = serialization.load_pem_private_key(
private_key.encode('utf-8'),
password=None,
backend=default_backend()
)
message_bytes = Bytes.object_to_bytes(message)
signature_bytes = private_key_bytes.sign(
message_bytes,
ec.ECDSA(hashes.SHA256())
)
return Bytes.encode_bytes(signature_bytes).decode('utf-8')
def verify(message: object, signature: str, public_key: str) -> bool:
"""
verfies message with digital signature
@param message: (object) message to verify
@param signature: (str) signature to verify message with
@param public_key: (str) public key to verify message with
"""
try:
public_key_bytes = serialization.load_pem_public_key(
public_key.encode('utf-8'),
backend=default_backend()
)
signature_bytes = Bytes.decode_bytes(signature.encode('utf-8'))
message_bytes = Bytes.object_to_bytes(message)
public_key_bytes.verify(
signature_bytes,
message_bytes,
ec.ECDSA(hashes.SHA256())
)
return True
except InvalidSignature:
return False