nucypher/tests/characters/test_bob_joins_policy_and_r...

201 lines
8.1 KiB
Python

import datetime
import os
import maya
import pytest
from constant_sorrow.constants import NO_DECRYPTION_PERFORMED
from nucypher.characters.lawful import Bob, Ursula
from nucypher.characters.lawful import Enrico
from nucypher.policy.collections import TreasureMap
from nucypher.utilities.sandbox.constants import (
NUMBER_OF_URSULAS_IN_DEVELOPMENT_NETWORK,
MOCK_POLICY_DEFAULT_M,
TEMPORARY_DOMAIN
)
from nucypher.utilities.sandbox.middleware import MockRestMiddleware
def test_federated_bob_full_retrieve_flow(federated_ursulas,
federated_bob,
federated_alice,
capsule_side_channel,
enacted_federated_policy):
# Assume for the moment that Bob has already received a TreasureMap.
treasure_map = enacted_federated_policy.treasure_map
federated_bob.treasure_maps[treasure_map.public_id()] = treasure_map
for ursula in federated_ursulas:
federated_bob.remember_node(ursula)
# The side channel delivers all that Bob needs at this point:
# - A single MessageKit, containing a Capsule
# - A representation of the data source
the_message_kit = capsule_side_channel()
alices_verifying_key = federated_alice.stamp.as_umbral_pubkey()
delivered_cleartexts = federated_bob.retrieve(the_message_kit,
enrico=capsule_side_channel.enrico,
alice_verifying_key=alices_verifying_key,
label=enacted_federated_policy.label)
# We show that indeed this is the passage originally encrypted by the Enrico.
assert b"Welcome to flippering number 1." == delivered_cleartexts[0]
def test_bob_joins_policy_and_retrieves(federated_alice,
federated_ursulas,
certificates_tempdir,
):
# Let's partition Ursulas in two parts
a_couple_of_ursulas = list(federated_ursulas)[:2]
rest_of_ursulas = list(federated_ursulas)[2:]
# Bob becomes
bob = Bob(federated_only=True,
domains={TEMPORARY_DOMAIN},
start_learning_now=True,
network_middleware=MockRestMiddleware(),
abort_on_learning_error=True,
known_nodes=a_couple_of_ursulas,
)
# Bob only knows a couple of Ursulas initially
assert len(bob.known_nodes) == 2
# Alice creates a policy granting access to Bob
# Just for fun, let's assume she distributes KFrags among Ursulas unknown to Bob
n = NUMBER_OF_URSULAS_IN_DEVELOPMENT_NETWORK - 2
label = b'label://' + os.urandom(32)
contract_end_datetime = maya.now() + datetime.timedelta(days=5)
policy = federated_alice.grant(bob=bob,
label=label,
m=3,
n=n,
expiration=contract_end_datetime,
handpicked_ursulas=set(rest_of_ursulas),
)
assert bob == policy.bob
assert label == policy.label
# Now, Bob joins the policy
bob.join_policy(label=label,
alice_verifying_key=federated_alice.stamp,
block=True)
# In the end, Bob should know all the Ursulas
assert len(bob.known_nodes) == len(federated_ursulas)
# Enrico becomes
enrico = Enrico(policy_encrypting_key=policy.public_key)
plaintext = b"What's your approach? Mississippis or what?"
message_kit, _signature = enrico.encrypt_message(plaintext)
alices_verifying_key = federated_alice.stamp.as_umbral_pubkey()
# Bob takes the message_kit and retrieves the message within
delivered_cleartexts = bob.retrieve(message_kit,
enrico=enrico,
alice_verifying_key=alices_verifying_key,
label=policy.label,
retain_cfrags=True)
assert plaintext == delivered_cleartexts[0]
# Bob tries to retrieve again, but without using the cached CFrags, it fails.
with pytest.raises(TypeError):
delivered_cleartexts = bob.retrieve(message_kit,
enrico=enrico,
alice_verifying_key=alices_verifying_key,
label=policy.label)
cleartexts_delivered_a_second_time = bob.retrieve(message_kit,
enrico=enrico,
alice_verifying_key=alices_verifying_key,
label=policy.label,
use_attached_cfrags=True)
# Indeed, they're the same cleartexts.
assert delivered_cleartexts == cleartexts_delivered_a_second_time
# Let's try retrieve again, but Alice revoked the policy.
failed_revocations = federated_alice.revoke(policy)
assert len(failed_revocations) == 0
# One thing to note here is that Bob *can* still retrieve with the cached CFrags, even though this Policy has been revoked. #892
_cleartexts = bob.retrieve(message_kit,
enrico=enrico,
alice_verifying_key=alices_verifying_key,
label=policy.label,
use_precedent_work_orders=True,
)
assert _cleartexts == delivered_cleartexts # TODO: 892
# OK, but we imagine that the message_kit is fresh here.
message_kit.capsule.clear_cfrags()
with pytest.raises(Ursula.NotEnoughUrsulas):
_cleartexts = bob.retrieve(message_kit,
enrico=enrico,
alice_verifying_key=alices_verifying_key,
label=policy.label,
)
def test_treasure_map_serialization(enacted_federated_policy, federated_bob):
treasure_map = enacted_federated_policy.treasure_map
assert treasure_map.m is not None
assert treasure_map.m != NO_DECRYPTION_PERFORMED
assert treasure_map.m == MOCK_POLICY_DEFAULT_M, 'm value is not correct'
serialized_map = bytes(treasure_map)
deserialized_map = TreasureMap.from_bytes(serialized_map)
assert deserialized_map._hrac == treasure_map._hrac
# TreasureMap is currently encrypted
with pytest.raises(TypeError):
deserialized_map.m
with pytest.raises(TypeError):
deserialized_map.destinations
compass = federated_bob.make_compass_for_alice(
enacted_federated_policy.alice)
deserialized_map.orient(compass)
assert deserialized_map.m == treasure_map.m
assert deserialized_map.destinations == treasure_map.destinations
def test_bob_retrieves_with_treasure_map(
federated_bob, federated_ursulas,
enacted_federated_policy, capsule_side_channel):
enrico = capsule_side_channel.enrico
message_kit = capsule_side_channel()
treasure_map = enacted_federated_policy.treasure_map
alice_verifying_key = enacted_federated_policy.alice.stamp
# Teach Bob about the network
federated_bob.remember_node(list(federated_ursulas)[0])
federated_bob.learn_from_teacher_node(eager=True)
# Deserialized treasure map
text1 = federated_bob.retrieve(
message_kit,
enrico=enrico,
alice_verifying_key=alice_verifying_key,
label=enacted_federated_policy.label,
treasure_map=treasure_map)
message_kit.capsule.clear_cfrags() # Return back to a non re-encrypted state
# Serialized treasure map
text2 = federated_bob.retrieve(
message_kit,
enrico=enrico,
alice_verifying_key=alice_verifying_key,
label=enacted_federated_policy.label,
treasure_map=bytes(treasure_map))
assert text1[0] == text2[0] == b'Welcome to flippering number 2.'