class CircuitNode:
def __init__(self, router, handshake_type=TorHandshakeType.NTOR):
self._router = router
self._handshake_type = handshake_type
self._key_agreement = None
self._crypto_state = None
self._window = TorWindow()
@property
def router(self):
return self._router
@property
def window(self):
return self._window
@property
def handshake_type(self):
return self._handshake_type
@property
def key_agreement(self):
if not self._key_agreement:
self._key_agreement = CircuitNode._get_key_agreement(
self._router, self._handshake_type)
return self._key_agreement
@staticmethod
def _get_key_agreement(onion_router, handshake_type):
if handshake_type == TorHandshakeType.NTOR:
return NtorKeyAgreement(onion_router)
elif handshake_type == TorHandshakeType.TAP:
return TapKeyAgreement(onion_router)
else:
raise NotImplementedError('Unknown key agreement')
def create_onion_skin(self):
return self.key_agreement.handshake
def complete_handshake(self, handshake_data):
shared_secret = self.key_agreement.complete_handshake(handshake_data)
self._crypto_state = CryptoState(shared_secret)
def encrypt_forward(self, relay_cell):
self._crypto_state.encrypt_forward(relay_cell)
def decrypt_backward(self, relay_cell):
self._crypto_state.decrypt_backward(relay_cell)
class CircuitNode:
def __init__(self,
router,
key_agreement_cls: Type[KeyAgreement] = NtorKeyAgreement):
self._router = router
self._key_agreement_cls = key_agreement_cls
self._crypto_state = None
self._window = TorWindow()
@property
def router(self):
return self._router
@property
def window(self):
return self._window
@property
def handshake_type(self):
return self._key_agreement_cls.TYPE
@cached_property
def key_agreement(self):
return self._key_agreement_cls(self._router)
def create_onion_skin(self):
return self.key_agreement.handshake
def complete_handshake(self, handshake_response):
shared_secret = self.key_agreement.complete_handshake(
handshake_response)
self._crypto_state = CryptoState(shared_secret)
def encrypt_forward(self, relay_cell):
self._crypto_state.encrypt_forward(relay_cell)
def decrypt_backward(self, relay_cell):
self._crypto_state.decrypt_backward(relay_cell)
def complete_handshake(self, handshake_data):
shared_secret = self.key_agreement.complete_handshake(handshake_data)
self._crypto_state = CryptoState(shared_secret)