def test_encrypt_forward_offset_no_ring_setting_nowrap(self):
''' The most basic of forward encrypts where the rotor is in position A
and the letter A is pressed. '''
rotor = Rotor('Test', 'EKMFLGDQVZNTOWYHXUSPAIBRCJ', ["Q"],
self._logger)
rotor.position = RotorContact.C.value
self.assertEqual(rotor.encrypt(RotorContact.A), RotorContact.K)
def test_wiring_incorrect_length(self):
try:
Rotor('Test rotor', 'ABC', ["Q"], self._logger)
except ValueError as ex:
self.assertEqual(str(ex), "Rotor wiring incorrect length")
else:
self.fail('ValueError not raised')
def test_wiring_not_string(self):
''' Test type check for wiring in constructor. '''
try:
Rotor('Test rotor', ['self.valid_rotor_wiring'], ["Q"],
self._logger)
except ValueError as ex:
self.assertEqual(str(ex), "Rotor wiring is not a string")
else:
self.fail('ValueError not raised')
def test_encrypt_backwards_with_offset_no_ring_setting_wrap(self):
'''
Verify that on pressing 'Z' (25) we get the encoded value of 'X' (23).
Explanation:
'Z' (25) is pressed with a rotor position of 5. The original input is
advanced 4 to 'D' which will return the letter 'B'. Because of the
position offset the result is adjusted down 4 to return 'X'.
'''
rotor = Rotor('Test', 'BDFHJLCPRTXVZNYEIWGAKMUSQO', ["Q"],
self._logger)
rotor.position = RotorContact.E.value
self.assertEqual(rotor.encrypt(RotorContact.Z, forward=False),
RotorContact.X)
def configure(self, model: str, rotors, reflector):
if model not in ENIGMA_MODELS:
raise ValueError('Enigma model is not valid')
self._model_details = ENIGMA_MODELS[model]
self._logger.log_debug(f"Configuring machine as '{model}'")
no_of_rotors_req = self._model_details.no_of_rotors.value
if len(rotors) != no_of_rotors_req:
self._last_error = 'Invalid number of rotors specified, ' + \
f'requires {no_of_rotors_req} rotors'
return False
for rotor in rotors:
details = [
r for r in self._model_details.rotors if r.name == rotor
]
if not details:
self._last_error = f"Rotor '{rotor}' is invalid, aborting!"
return False
details = details[0]
entry = Rotor(details.name, details.wiring, details.notches,
self._logger)
self._rotors.append(entry)
self._logger.log_debug(f"Added rotor '{rotor}'")
if self._model_details.has_plugboard:
self._logger.log_debug("Machine is using a plugboard")
self._plugboard = Plugboard()
details = [
r for r in self._model_details.reflectors if r.name == reflector
]
if not details:
self._last_error = f"Reflector '{reflector}' is invalid, aborting!"
return False
self._logger.log_debug(f"Added reflector '{reflector}'")
self._reflector = Reflector(details[0].name, details[0].wiring)
self._is_configured = True
return True
def test_encrypt_backwards_with_offset_no_ring_setting_nowrap(self):
'''
Verify that on pressing 'I' (9) we get the encoded value of 'S' (18).
Explanation:
'I' (9) is pressed with a rotor position of 3, the encoded letter that
is returned is 'S' (18) because the input is advanced 2 to 'K', which
will return the letter 'U'. Because off the 2 position offset we then
need to adjust the result down 2 to return 'S'.
'''
rotor = Rotor('Test', 'BDFHJLCPRTXVZNYEIWGAKMUSQO', ["Q"],
self._logger)
rotor.position = RotorContact.C.value
self.assertEqual(rotor.encrypt(RotorContact.I, forward=False),
RotorContact.S)
def test_encrypt_forward_offset_no_ring_setting_wrap(self):
'''
Verify that when key 'S' (18) is pressed when the rotor is rotated 3
positions we get the encoded contact of 'X' (23).
Explanation:
Key 'S' (18) is pressed, as the rotor is in position 3 (C) this means
it goes the wiring circuit of 'U' resulting in an encoded value of 'A'.
As the rotor is in position 3 we need to adjust the output by a value
of 2, therefore 'Y' is returned.
'''
rotor = Rotor('Test', 'EKMFLGDQVZNTOWYHXUSPAIBRCJ', ["Q"],
self._logger)
rotor.position = RotorContact.C.value
self.assertEqual(rotor.encrypt(RotorContact.S), RotorContact.Y)
def setUp(self):
self._logger = Logger(__name__, write_to_console=False)
self._valid_pass_through_rotor = Rotor('Pass Through Rotor',
self.PASS_THROUGH_ROTOR_WIRING,
["Q"], self._logger)