def answer_challenge(connection, authkey):
import hmac
assert isinstance(authkey, bytes)
message = connection.recv_bytes(256) # reject large message
assert message[:len(CHALLENGE)] == CHALLENGE, 'message = %r' % message
message = message[len(CHALLENGE):]
digest = hmac.new(authkey, message).digest()
connection.send_bytes(digest)
response = connection.recv_bytes(256) # reject large message
if response != WELCOME:
raise AuthenticationError('digest sent was rejected')
def deliver_challenge(connection, authkey):
import hmac
assert isinstance(authkey, bytes)
message = os.urandom(MESSAGE_LENGTH)
connection.send_bytes(CHALLENGE + message)
digest = hmac.new(authkey, message).digest()
response = connection.recv_bytes(256) # reject large message
if response == digest:
connection.send_bytes(WELCOME)
else:
connection.send_bytes(FAILURE)
raise AuthenticationError('digest received was wrong')