def setUp(self) -> None:
"""Pre-test actions."""
self.unit_test_dir = cd_unit_test()
self.master_key = MasterKey()
self.settings = Settings()
self.file_name = f'{DIR_USER_DATA}{self.settings.software_operation}_keys'
self.keylist = KeyList(self.master_key, self.settings)
self.full_contact_list = ['Alice', 'Bob', 'Charlie', LOCAL_ID]
self.keylist.keysets = [create_keyset(n, store_f=self.keylist.store_keys) for n in self.full_contact_list]
def setUp(self):
self.master_key = MasterKey()
self.settings = Settings()
self.keylist = KeyList(MasterKey(), Settings())
self.keylist.keysets = [
create_keyset(n, store_f=self.keylist.store_keys)
for n in ['Alice', 'Bob', 'Charlie']
]
self.keylist.store_keys()
def test_load_of_modified_database_raises_critical_error(self):
self.keylist.store_keys()
# Test reading works normally
self.assertIsInstance(KeyList(self.master_key, self.settings), KeyList)
# Test loading of the tampered database raises CriticalError
tamper_file(self.file_name, tamper_size=1)
with self.assertRaises(SystemExit):
KeyList(self.master_key, self.settings)
def test_storing_and_loading_of_keysets(self):
# Test store
self.keylist.store_keys()
self.assertEqual(
os.path.getsize(self.file_name), XCHACHA20_NONCE_LENGTH +
(self.settings.max_number_of_contacts + 1) * KEYSET_LENGTH +
POLY1305_TAG_LENGTH)
# Test load
key_list2 = KeyList(MasterKey(), Settings())
self.assertEqual(len(key_list2.keysets), len(self.full_contact_list))
def test_storing_and_loading_of_keysets(self):
# Test Store
self.assertTrue(os.path.isfile(f'{DIR_USER_DATA}ut_keys'))
self.assertEqual(
os.path.getsize(f'{DIR_USER_DATA}ut_keys'), XSALSA20_NONCE_LEN +
self.settings.max_number_of_contacts * KEYSET_LENGTH +
POLY1305_TAG_LEN)
# Test load
keylist2 = KeyList(MasterKey(), Settings())
self.assertEqual(len(keylist2.keysets), 3)
def test_invalid_content_raises_critical_error(self) -> None:
# Setup
invalid_data = b'a'
pt_bytes = b''.join([k.serialize_k() for k in self.keylist.keysets + self.keylist._dummy_keysets()])
ct_bytes = encrypt_and_sign(pt_bytes + invalid_data, self.master_key.master_key)
ensure_dir(DIR_USER_DATA)
with open(self.file_name, 'wb+') as f:
f.write(ct_bytes)
# Test
with self.assertRaises(SystemExit):
KeyList(self.master_key, self.settings)
def test_change_master_key(self):
key = SYMMETRIC_KEY_LENGTH * b'\x01'
master_key2 = MasterKey(master_key=key)
# Test that new key is different from existing one
self.assertNotEqual(key, self.master_key.master_key)
# Change master key
self.assertIsNone(self.keylist.change_master_key(master_key2))
# Test that master key has changed
self.assertEqual(self.keylist.master_key.master_key, key)
# Test that loading of the database with new key succeeds
self.assertIsInstance(KeyList(master_key2, self.settings), KeyList)
class TestKeyList(unittest.TestCase):
def setUp(self):
self.unittest_dir = cd_unittest()
self.master_key = MasterKey()
self.settings = Settings()
self.file_name = f'{DIR_USER_DATA}{self.settings.software_operation}_keys'
self.keylist = KeyList(self.master_key, self.settings)
self.full_contact_list = ['Alice', 'Bob', 'Charlie', LOCAL_ID]
self.keylist.keysets = [
create_keyset(n, store_f=self.keylist.store_keys)
for n in self.full_contact_list
]
def tearDown(self):
cleanup(self.unittest_dir)
def test_storing_and_loading_of_keysets(self):
# Test store
self.keylist.store_keys()
self.assertEqual(
os.path.getsize(self.file_name), XCHACHA20_NONCE_LENGTH +
(self.settings.max_number_of_contacts + 1) * KEYSET_LENGTH +
POLY1305_TAG_LENGTH)
# Test load
key_list2 = KeyList(MasterKey(), Settings())
self.assertEqual(len(key_list2.keysets), len(self.full_contact_list))
def test_load_of_modified_database_raises_critical_error(self):
self.keylist.store_keys()
# Test reading works normally
self.assertIsInstance(KeyList(self.master_key, self.settings), KeyList)
# Test loading of the tampered database raises CriticalError
tamper_file(self.file_name, tamper_size=1)
with self.assertRaises(SystemExit):
KeyList(self.master_key, self.settings)
def test_invalid_content_raises_critical_error(self):
# Setup
invalid_data = b'a'
pt_bytes = b''.join([
k.serialize_k()
for k in self.keylist.keysets + self.keylist._dummy_keysets()
])
ct_bytes = encrypt_and_sign(pt_bytes + invalid_data,
self.master_key.master_key)
ensure_dir(DIR_USER_DATA)
with open(self.file_name, 'wb+') as f:
f.write(ct_bytes)
# Test
with self.assertRaises(SystemExit):
KeyList(self.master_key, self.settings)
def test_generate_dummy_keyset(self):
dummy_keyset = self.keylist.generate_dummy_keyset()
self.assertEqual(len(dummy_keyset.serialize_k()), KEYSET_LENGTH)
self.assertIsInstance(dummy_keyset, KeySet)
def test_dummy_keysets(self):
dummies = self.keylist._dummy_keysets()
self.assertEqual(len(dummies),
(self.settings.max_number_of_contacts + 1) -
len(self.full_contact_list))
for c in dummies:
self.assertIsInstance(c, KeySet)
def test_add_keyset(self):
new_key = bytes(SYMMETRIC_KEY_LENGTH)
self.keylist.keysets = [create_keyset(LOCAL_ID)]
# Check that KeySet exists and that its keys are different
self.assertNotEqual(self.keylist.keysets[0].rx_hk, new_key)
# Replace existing KeySet
self.assertIsNone(
self.keylist.add_keyset(LOCAL_PUBKEY, new_key, new_key, new_key,
new_key))
# Check that new KeySet replaced the old one
self.assertEqual(self.keylist.keysets[0].onion_pub_key, LOCAL_PUBKEY)
self.assertEqual(self.keylist.keysets[0].rx_hk, new_key)
def test_remove_keyset(self):
# Test KeySet for Bob exists
self.assertTrue(self.keylist.has_keyset(nick_to_pub_key('Bob')))
# Remove KeySet for Bob
self.assertIsNone(self.keylist.remove_keyset(nick_to_pub_key('Bob')))
# Test KeySet was removed
self.assertFalse(self.keylist.has_keyset(nick_to_pub_key('Bob')))
def test_change_master_key(self):
key = SYMMETRIC_KEY_LENGTH * b'\x01'
master_key2 = MasterKey(master_key=key)
# Test that new key is different from existing one
self.assertNotEqual(key, self.master_key.master_key)
# Change master key
self.assertIsNone(self.keylist.change_master_key(master_key2))
# Test that master key has changed
self.assertEqual(self.keylist.master_key.master_key, key)
# Test that loading of the database with new key succeeds
self.assertIsInstance(KeyList(master_key2, self.settings), KeyList)
def test_update_database(self):
self.assertEqual(os.path.getsize(self.file_name), 9016)
self.assertIsNone(
self.keylist.manage(KDB_UPDATE_SIZE_HEADER,
Settings(max_number_of_contacts=100)))
self.assertEqual(os.path.getsize(self.file_name), 17816)
self.assertEqual(self.keylist.settings.max_number_of_contacts, 100)
def test_get_keyset(self):
keyset = self.keylist.get_keyset(nick_to_pub_key('Alice'))
self.assertIsInstance(keyset, KeySet)
def test_get_list_of_pub_keys(self):
self.assertEqual(self.keylist.get_list_of_pub_keys(), [
nick_to_pub_key("Alice"),
nick_to_pub_key("Bob"),
nick_to_pub_key("Charlie")
])
def test_has_keyset(self):
self.keylist.keysets = []
self.assertFalse(self.keylist.has_keyset(nick_to_pub_key("Alice")))
self.keylist.keysets = [create_keyset('Alice')]
self.assertTrue(self.keylist.has_keyset(nick_to_pub_key("Alice")))
def test_has_rx_mk(self):
self.assertTrue(self.keylist.has_rx_mk(nick_to_pub_key('Bob')))
self.keylist.get_keyset(
nick_to_pub_key('Bob')).rx_mk = bytes(SYMMETRIC_KEY_LENGTH)
self.keylist.get_keyset(
nick_to_pub_key('Bob')).rx_hk = bytes(SYMMETRIC_KEY_LENGTH)
self.assertFalse(self.keylist.has_rx_mk(nick_to_pub_key('Bob')))
def test_has_local_keyset(self):
self.keylist.keysets = []
self.assertFalse(self.keylist.has_local_keyset())
self.assertIsNone(
self.keylist.add_keyset(LOCAL_PUBKEY, bytes(SYMMETRIC_KEY_LENGTH),
bytes(SYMMETRIC_KEY_LENGTH),
bytes(SYMMETRIC_KEY_LENGTH),
bytes(SYMMETRIC_KEY_LENGTH)))
self.assertTrue(self.keylist.has_local_keyset())
def test_manage(self):
# Test that KeySet for David does not exist
self.assertFalse(self.keylist.has_keyset(nick_to_pub_key('David')))
# Test adding KeySet
self.assertIsNone(
self.keylist.manage(KDB_ADD_ENTRY_HEADER, nick_to_pub_key('David'),
bytes(SYMMETRIC_KEY_LENGTH),
bytes(SYMMETRIC_KEY_LENGTH),
bytes(SYMMETRIC_KEY_LENGTH),
bytes(SYMMETRIC_KEY_LENGTH)))
self.assertTrue(self.keylist.has_keyset(nick_to_pub_key('David')))
# Test removing KeySet
self.assertIsNone(
self.keylist.manage(KDB_REMOVE_ENTRY_HEADER,
nick_to_pub_key('David')))
self.assertFalse(self.keylist.has_keyset(nick_to_pub_key('David')))
# Test changing master key
new_key = SYMMETRIC_KEY_LENGTH * b'\x01'
self.assertNotEqual(self.master_key.master_key, new_key)
self.assertIsNone(
self.keylist.manage(KDB_CHANGE_MASTER_KEY_HEADER,
MasterKey(master_key=new_key)))
self.assertEqual(self.keylist.master_key.master_key, new_key)
# Test updating key_database with new settings changes database size.
self.assertEqual(os.path.getsize(self.file_name), 9016)
self.assertIsNone(
self.keylist.manage(KDB_UPDATE_SIZE_HEADER,
Settings(max_number_of_contacts=100)))
self.assertEqual(os.path.getsize(self.file_name), 17816)
# Test invalid KeyList management command raises Critical Error
with self.assertRaises(SystemExit):
self.keylist.manage('invalid_key', None)
def change_master_key(user_input: 'UserInput', contact_list: 'ContactList',
group_list: 'GroupList', settings: 'Settings',
queues: 'QueueDict', master_key: 'MasterKey',
onion_service: 'OnionService') -> None:
"""Change the master key on Transmitter/Receiver Program."""
if settings.traffic_masking:
raise SoftError("Error: Command is disabled during traffic masking.",
head_clear=True)
try:
device = user_input.plaintext.split()[1].lower()
except IndexError:
raise SoftError(
f"Error: No target-system ('{TX}' or '{RX}') specified.",
head_clear=True)
if device not in [TX, RX]:
raise SoftError(f"Error: Invalid target system '{device}'.",
head_clear=True)
if device == RX:
queue_command(CH_MASTER_KEY, settings, queues)
return None
authenticated = master_key.authenticate_action()
if authenticated:
# Cache old master key to allow log file re-encryption.
old_master_key = master_key.master_key[:]
# Create new master key but do not store new master key data into any database.
new_master_key = master_key.master_key = master_key.new_master_key(
replace=False)
phase("Re-encrypting databases")
# Halt `sender_loop` for the duration of database re-encryption.
queues[KEY_MANAGEMENT_QUEUE].put((KDB_M_KEY_CHANGE_HALT_HEADER, ))
wait_for_key_db_halt(queues)
# Load old key_list from database file as it's not used on input_loop side.
key_list = KeyList(master_key, settings)
# Update encryption keys for databases
contact_list.database.database_key = new_master_key
key_list.database.database_key = new_master_key
group_list.database.database_key = new_master_key
settings.database.database_key = new_master_key
onion_service.database.database_key = new_master_key
# Create temp databases for each database, do not replace original.
with ignored(SoftError):
change_log_db_key(old_master_key, new_master_key, settings)
contact_list.store_contacts(replace=False)
key_list.store_keys(replace=False)
group_list.store_groups(replace=False)
settings.store_settings(replace=False)
onion_service.store_onion_service_private_key(replace=False)
# At this point all temp files exist and they have been checked to be valid by the respective
# temp file writing function. It's now time to create a temp file for the new master key
# database. Once the temp master key database is created, the `replace_database_data()` method
# will also run the atomic `os.replace()` command for the master key database.
master_key.replace_database_data()
# Next we do the atomic `os.replace()` for all other files too.
replace_log_db(settings)
contact_list.database.replace_database()
key_list.database.replace_database()
group_list.database.replace_database()
settings.database.replace_database()
onion_service.database.replace_database()
# Now all databases have been updated. It's time to let
# the key database know what the new master key is.
queues[KEY_MANAGEMENT_QUEUE].put(new_master_key)
wait_for_key_db_ack(new_master_key, queues)
phase(DONE)
m_print("Master key successfully changed.",
bold=True,
tail_clear=True,
delay=1,
head=1)
def main() -> None:
"""Load persistent data and launch the Transmitter/Receiver Program.
This function decrypts user data from databases and launches
processes for Transmitter or Receiver Program. It then monitors the
EXIT_QUEUE for EXIT/WIPE signals and each process in case one of
them dies.
If you're reading this code to get the big picture on how TFC works,
start by looking at the loop functions below, defined as the target
for each process, from top to bottom:
From `input_loop` process, you can see how the Transmitter
Program processes a message or command from the user, creates
assembly packets for a message/file/command, and how those are
eventually pushed into a multiprocessing queue, from where they are
loaded by the `sender_loop`.
The `sender_loop` process encrypts outgoing assembly packets,
and outputs the encrypted datagrams to the Networked Computer. The
process also sends assembly packets to the `log_writer_loop`.
The `log_writer_loop` process filters out non-message assembly
packets and if logging for contact is enabled, stores the message
assembly packet into an encrypted log database.
The `noise_loop` processes are used to provide the `sender_loop`
an interface identical to that of the `input_loop`. The
`sender_loop` uses the interface to load noise packets/commands when
traffic masking is enabled.
Refer to the file `relay.py` to see how the Relay Program on
Networked Computer manages datagrams between the network and
Source/Destination Computer.
In Receiver Program (also launched by this file), the `gateway_loop`
process acts as a buffer for incoming datagrams. This buffer is
consumed by the `receiver_loop` process that organizes datagrams
loaded from the buffer into a set of queues depending on datagram
type. Finally, the `output_loop` process loads and processes
datagrams from the queues in the order of priority.
"""
working_dir = f'{os.getenv("HOME")}/{DIR_TFC}'
ensure_dir(working_dir)
os.chdir(working_dir)
operation, local_test, data_diode_sockets = process_arguments()
check_kernel_version()
check_kernel_entropy()
print_title(operation)
master_key = MasterKey( operation, local_test)
gateway = Gateway( operation, local_test, data_diode_sockets)
settings = Settings( master_key, operation, local_test)
contact_list = ContactList(master_key, settings)
key_list = KeyList( master_key, settings)
group_list = GroupList( master_key, settings, contact_list)
if settings.software_operation == TX:
onion_service = OnionService(master_key)
queues = {MESSAGE_PACKET_QUEUE: Queue(), # Standard messages
COMMAND_PACKET_QUEUE: Queue(), # Standard commands
TM_MESSAGE_PACKET_QUEUE: Queue(), # Traffic masking messages
TM_FILE_PACKET_QUEUE: Queue(), # Traffic masking files
TM_COMMAND_PACKET_QUEUE: Queue(), # Traffic masking commands
TM_NOISE_PACKET_QUEUE: Queue(), # Traffic masking noise packets
TM_NOISE_COMMAND_QUEUE: Queue(), # Traffic masking noise commands
RELAY_PACKET_QUEUE: Queue(), # Unencrypted datagrams to Networked Computer
LOG_PACKET_QUEUE: Queue(), # `log_writer_loop` assembly packets to be logged
LOG_SETTING_QUEUE: Queue(), # `log_writer_loop` logging state management between noise packets
TRAFFIC_MASKING_QUEUE: Queue(), # `log_writer_loop` traffic masking setting management commands
LOGFILE_MASKING_QUEUE: Queue(), # `log_writer_loop` logfile masking setting management commands
KEY_MANAGEMENT_QUEUE: Queue(), # `sender_loop` key database management commands
SENDER_MODE_QUEUE: Queue(), # `sender_loop` default/traffic masking mode switch commands
WINDOW_SELECT_QUEUE: Queue(), # `sender_loop` window selection commands during traffic masking
EXIT_QUEUE: Queue() # EXIT/WIPE signal from `input_loop` to `main`
} # type: Dict[bytes, Queue]
process_list = [Process(target=input_loop, args=(queues, settings, gateway, contact_list, group_list,
master_key, onion_service, sys.stdin.fileno())),
Process(target=sender_loop, args=(queues, settings, gateway, key_list)),
Process(target=log_writer_loop, args=(queues, settings)),
Process(target=noise_loop, args=(queues, contact_list)),
Process(target=noise_loop, args=(queues,))]
else:
queues = {GATEWAY_QUEUE: Queue(), # Buffer for incoming datagrams
LOCAL_KEY_DATAGRAM_HEADER: Queue(), # Local key datagrams
MESSAGE_DATAGRAM_HEADER: Queue(), # Message datagrams
FILE_DATAGRAM_HEADER: Queue(), # File datagrams
COMMAND_DATAGRAM_HEADER: Queue(), # Command datagrams
EXIT_QUEUE: Queue() # EXIT/WIPE signal from `output_loop` to `main`
}
process_list = [Process(target=gateway_loop, args=(queues, gateway)),
Process(target=receiver_loop, args=(queues, gateway)),
Process(target=output_loop, args=(queues, gateway, settings, contact_list, key_list,
group_list, master_key, sys.stdin.fileno()))]
for p in process_list:
p.start()
monitor_processes(process_list, settings.software_operation, queues)
class TestKeyList(unittest.TestCase):
def setUp(self):
self.master_key = MasterKey()
self.settings = Settings()
self.keylist = KeyList(MasterKey(), Settings())
self.keylist.keysets = [
create_keyset(n, store_f=self.keylist.store_keys)
for n in ['Alice', 'Bob', 'Charlie']
]
self.keylist.store_keys()
def tearDown(self):
cleanup()
def test_storing_and_loading_of_keysets(self):
# Test Store
self.assertTrue(os.path.isfile(f'{DIR_USER_DATA}ut_keys'))
self.assertEqual(
os.path.getsize(f'{DIR_USER_DATA}ut_keys'), XSALSA20_NONCE_LEN +
self.settings.max_number_of_contacts * KEYSET_LENGTH +
POLY1305_TAG_LEN)
# Test load
keylist2 = KeyList(MasterKey(), Settings())
self.assertEqual(len(keylist2.keysets), 3)
def test_change_master_key(self):
key = KEY_LENGTH * b'\x01'
masterkey2 = MasterKey(master_key=key)
self.keylist.change_master_key(masterkey2)
self.assertEqual(self.keylist.master_key.master_key, key)
def test_generate_dummy_keyset(self):
dummy_keyset = self.keylist.generate_dummy_keyset()
self.assertEqual(len(dummy_keyset.serialize_k()), KEYSET_LENGTH)
self.assertIsInstance(dummy_keyset, KeySet)
def test_get_keyset(self):
keyset = self.keylist.get_keyset('*****@*****.**')
self.assertIsInstance(keyset, KeySet)
def test_has_local_key_and_add_keyset(self):
self.assertFalse(self.keylist.has_local_key())
self.assertIsNone(
self.keylist.add_keyset(LOCAL_ID, bytes(KEY_LENGTH),
bytes(KEY_LENGTH), bytes(KEY_LENGTH),
bytes(KEY_LENGTH)))
self.assertIsNone(
self.keylist.add_keyset(LOCAL_ID, bytes(KEY_LENGTH),
bytes(KEY_LENGTH), bytes(KEY_LENGTH),
bytes(KEY_LENGTH)))
self.assertTrue(self.keylist.has_local_key())
def test_has_keyset_and_remove_keyset(self):
self.assertTrue(self.keylist.has_keyset('*****@*****.**'))
self.assertIsNone(self.keylist.remove_keyset('*****@*****.**'))
self.assertFalse(self.keylist.has_keyset('*****@*****.**'))
def test_has_rx_key(self):
self.assertTrue(self.keylist.has_rx_key('*****@*****.**'))
self.keylist.get_keyset('*****@*****.**').rx_key = bytes(KEY_LENGTH)
self.keylist.get_keyset('*****@*****.**').rx_hek = bytes(KEY_LENGTH)
self.assertFalse(self.keylist.has_rx_key('*****@*****.**'))
def test_manage_keylist(self):
self.assertFalse(self.keylist.has_keyset('*****@*****.**'))
self.assertIsNone(
self.keylist.manage(KDB_ADD_ENTRY_HEADER, '*****@*****.**',
bytes(KEY_LENGTH), bytes(KEY_LENGTH),
bytes(KEY_LENGTH), bytes(KEY_LENGTH)))
self.assertTrue(self.keylist.has_keyset('*****@*****.**'))
self.assertIsNone(
self.keylist.manage(KDB_REMOVE_ENTRY_HEADER, '*****@*****.**'))
self.assertFalse(self.keylist.has_keyset('*****@*****.**'))
self.assertIsNone(
self.keylist.manage(KDB_CHANGE_MASTER_KEY_HEADER,
MasterKey(master_key=KEY_LENGTH * b'\x01')))
self.assertEqual(self.keylist.master_key.master_key,
KEY_LENGTH * b'\x01')
with self.assertRaises(SystemExit):
self.keylist.manage('invalid_key', None)
def main() -> None:
"""Derive master key, decrypt databases and initialize processes."""
os.chdir(sys.path[0])
init_entropy()
operation, local_test, dd_sockets = process_arguments()
clear_screen()
c_print("TFC", head=1, tail=1)
master_key = MasterKey(operation, local_test)
settings = Settings(master_key, operation, local_test, dd_sockets)
contact_list = ContactList(master_key, settings)
key_list = KeyList(master_key, settings)
group_list = GroupList(master_key, settings, contact_list)
gateway = Gateway(settings)
process_list = []
if settings.software_operation == 'tx':
queues = {
MESSAGE_PACKET_QUEUE: Queue(),
FILE_PACKET_QUEUE: Queue(),
COMMAND_PACKET_QUEUE: Queue(),
LOG_PACKET_QUEUE: Queue(),
NOISE_PACKET_QUEUE: Queue(),
NOISE_COMMAND_QUEUE: Queue(),
KEY_MANAGEMENT_QUEUE: Queue(),
WINDOW_SELECT_QUEUE: Queue()
}
if settings.session_trickle:
np_filler = Process(target=noise_process,
args=(P_N_HEADER, queues[NOISE_PACKET_QUEUE],
contact_list))
nc_filler = Process(target=noise_process,
args=(C_N_HEADER, queues[NOISE_COMMAND_QUEUE]))
process_list.extend([np_filler, nc_filler])
for p in [np_filler, nc_filler]:
p.start()
while any([
q.qsize() < 1000 for q in
[queues[NOISE_PACKET_QUEUE], queues[NOISE_COMMAND_QUEUE]]
]):
time.sleep(0.1)
sender_process = Process(target=sender_loop,
args=(settings, queues, gateway, key_list))
input_process = Process(target=tx_loop,
args=(settings, queues, gateway,
contact_list, group_list, master_key,
sys.stdin.fileno()))
log_process = Process(target=log_writer,
args=(queues[LOG_PACKET_QUEUE], ))
process_list.extend([sender_process, input_process, log_process])
for p in [sender_process, input_process, log_process]:
p.start()
elif settings.software_operation == 'rx':
queues = {
LOCAL_KEY_PACKET_HEADER: Queue(),
PUBLIC_KEY_PACKET_HEADER: Queue(),
MESSAGE_PACKET_HEADER: Queue(),
COMMAND_PACKET_HEADER: Queue(),
IMPORTED_FILE_CT_HEADER: Queue(),
GATEWAY_QUEUE: Queue()
}
gateway_process = Process(target=gw_incoming,
args=(gateway, queues[GATEWAY_QUEUE]))
receiver_process = Process(target=receiver_loop,
args=(settings, queues))
output_process = Process(target=rx_loop,
args=(settings, queues, contact_list,
key_list, group_list, master_key,
sys.stdin.fileno()))
process_list.extend(
[gateway_process, receiver_process, output_process])
for p in [gateway_process, receiver_process, output_process]:
p.start()
while True:
try:
time.sleep(0.1)
if not all([p.is_alive() for p in process_list]):
for p in process_list:
p.terminate()
exit()
except (EOFError, KeyboardInterrupt):
pass
class TestKeyList(unittest.TestCase):
def setUp(self) -> None:
"""Pre-test actions."""
self.unit_test_dir = cd_unit_test()
self.master_key = MasterKey()
self.settings = Settings()
self.file_name = f'{DIR_USER_DATA}{self.settings.software_operation}_keys'
self.keylist = KeyList(self.master_key, self.settings)
self.full_contact_list = ['Alice', 'Bob', 'Charlie', LOCAL_ID]
self.keylist.keysets = [
create_keyset(n, store_f=self.keylist.store_keys)
for n in self.full_contact_list
]
def tearDown(self) -> None:
"""Post-test actions."""
cleanup(self.unit_test_dir)
def test_storing_and_loading_of_keysets(self) -> None:
# Test store
self.keylist.store_keys()
self.assertEqual(
os.path.getsize(self.file_name), XCHACHA20_NONCE_LENGTH +
(self.settings.max_number_of_contacts + 1) * KEYSET_LENGTH +
POLY1305_TAG_LENGTH)
# Test load
key_list2 = KeyList(MasterKey(), Settings())
self.assertEqual(len(key_list2.keysets), len(self.full_contact_list))
def test_load_of_modified_database_raises_critical_error(self) -> None:
self.keylist.store_keys()
# Test reading works normally
self.assertIsInstance(KeyList(self.master_key, self.settings), KeyList)
# Test loading of the tampered database raises CriticalError
tamper_file(self.file_name, tamper_size=1)
with self.assertRaises(SystemExit):
KeyList(self.master_key, self.settings)
def test_invalid_content_raises_critical_error(self) -> None:
# Setup
invalid_data = b'a'
pt_bytes = b''.join([
k.serialize_k()
for k in self.keylist.keysets + self.keylist._dummy_keysets()
])
ct_bytes = encrypt_and_sign(pt_bytes + invalid_data,
self.master_key.master_key)
ensure_dir(DIR_USER_DATA)
with open(self.file_name, 'wb+') as f:
f.write(ct_bytes)
# Test
with self.assertRaises(SystemExit):
KeyList(self.master_key, self.settings)
def test_generate_dummy_keyset(self) -> None:
dummy_keyset = self.keylist.generate_dummy_keyset()
self.assertEqual(len(dummy_keyset.serialize_k()), KEYSET_LENGTH)
self.assertIsInstance(dummy_keyset, KeySet)
def test_dummy_keysets(self) -> None:
dummies = self.keylist._dummy_keysets()
self.assertEqual(len(dummies),
(self.settings.max_number_of_contacts + 1) -
len(self.full_contact_list))
for c in dummies:
self.assertIsInstance(c, KeySet)
def test_add_keyset(self) -> None:
new_key = bytes(SYMMETRIC_KEY_LENGTH)
self.keylist.keysets = [create_keyset(LOCAL_ID)]
# Check that KeySet exists and that its keys are different from the new ones
self.assertNotEqual(self.keylist.keysets[0].rx_hk, new_key)
# Replace the existing KeySet
self.assertIsNone(
self.keylist.add_keyset(LOCAL_PUBKEY, new_key, new_key, new_key,
new_key))
# Check that the new KeySet replaced the old one
self.assertEqual(self.keylist.keysets[0].onion_pub_key, LOCAL_PUBKEY)
self.assertEqual(self.keylist.keysets[0].rx_hk, new_key)
def test_remove_keyset(self) -> None:
# Test that the KeySet for Bob exists
self.assertTrue(self.keylist.has_keyset(nick_to_pub_key('Bob')))
# Remove the KeySet for Bob
self.assertIsNone(self.keylist.remove_keyset(nick_to_pub_key('Bob')))
# Test that the KeySet was removed
self.assertFalse(self.keylist.has_keyset(nick_to_pub_key('Bob')))
@mock.patch('builtins.input', side_effect=['test_password'])
def test_change_master_key(self, _: Any) -> None:
# Setup
key = SYMMETRIC_KEY_LENGTH * b'\x01'
master_key2 = MasterKey(master_key=key)
queues = gen_queue_dict()
def queue_delayer() -> None:
"""Place packet to the key management queue after timer runs out."""
time.sleep(0.1)
queues[KEY_MANAGEMENT_QUEUE].put(master_key2.master_key)
threading.Thread(target=queue_delayer).start()
# Test that the new key is different from the existing one
self.assertNotEqual(key, self.master_key.master_key)
# Change the master key
self.assertIsNone(self.keylist.change_master_key(queues))
# Test that the master key was changed
self.assertEqual(self.keylist.master_key.master_key, key)
self.assertEqual(self.keylist.database.database_key, key)
self.assertEqual(queues[KEY_MGMT_ACK_QUEUE].get(), KDB_HALT_ACK_HEADER)
self.assertEqual(queues[KEY_MGMT_ACK_QUEUE].get(), key)
def test_update_database(self) -> None:
# Setup
queues = gen_queue_dict()
# Test
self.assertEqual(os.path.getsize(self.file_name), 9016)
self.assertIsNone(
self.keylist.manage(queues, KDB_UPDATE_SIZE_HEADER,
Settings(max_number_of_contacts=100)))
self.assertEqual(os.path.getsize(self.file_name), 17816)
self.assertEqual(self.keylist.settings.max_number_of_contacts, 100)
def test_get_keyset(self) -> None:
keyset = self.keylist.get_keyset(nick_to_pub_key('Alice'))
self.assertIsInstance(keyset, KeySet)
def test_get_list_of_pub_keys(self) -> None:
self.assertEqual(self.keylist.get_list_of_pub_keys(), [
nick_to_pub_key("Alice"),
nick_to_pub_key("Bob"),
nick_to_pub_key("Charlie")
])
def test_has_keyset(self) -> None:
self.keylist.keysets = []
self.assertFalse(self.keylist.has_keyset(nick_to_pub_key("Alice")))
self.keylist.keysets = [create_keyset('Alice')]
self.assertTrue(self.keylist.has_keyset(nick_to_pub_key("Alice")))
def test_has_rx_mk(self) -> None:
self.assertTrue(self.keylist.has_rx_mk(nick_to_pub_key('Bob')))
self.keylist.get_keyset(
nick_to_pub_key('Bob')).rx_mk = bytes(SYMMETRIC_KEY_LENGTH)
self.keylist.get_keyset(
nick_to_pub_key('Bob')).rx_hk = bytes(SYMMETRIC_KEY_LENGTH)
self.assertFalse(self.keylist.has_rx_mk(nick_to_pub_key('Bob')))
def test_has_local_keyset(self) -> None:
self.keylist.keysets = []
self.assertFalse(self.keylist.has_local_keyset())
self.assertIsNone(
self.keylist.add_keyset(LOCAL_PUBKEY, bytes(SYMMETRIC_KEY_LENGTH),
bytes(SYMMETRIC_KEY_LENGTH),
bytes(SYMMETRIC_KEY_LENGTH),
bytes(SYMMETRIC_KEY_LENGTH)))
self.assertTrue(self.keylist.has_local_keyset())
def test_manage(self) -> None:
# Setup
queues = gen_queue_dict()
# Test that the KeySet for David does not exist
self.assertFalse(self.keylist.has_keyset(nick_to_pub_key('David')))
# Test adding the KeySet for David
self.assertIsNone(
self.keylist.manage(queues, KDB_ADD_ENTRY_HEADER,
nick_to_pub_key('David'),
bytes(SYMMETRIC_KEY_LENGTH),
bytes(SYMMETRIC_KEY_LENGTH),
bytes(SYMMETRIC_KEY_LENGTH),
bytes(SYMMETRIC_KEY_LENGTH)))
self.assertTrue(self.keylist.has_keyset(nick_to_pub_key('David')))
# Test removing David's KeySet
self.assertIsNone(
self.keylist.manage(queues, KDB_REMOVE_ENTRY_HEADER,
nick_to_pub_key('David')))
self.assertFalse(self.keylist.has_keyset(nick_to_pub_key('David')))
# Test changing the master key
new_key = SYMMETRIC_KEY_LENGTH * b'\x01'
self.assertNotEqual(self.master_key.master_key, new_key)
queues[KEY_MANAGEMENT_QUEUE].put(new_key)
self.assertIsNone(
self.keylist.manage(queues, KDB_M_KEY_CHANGE_HALT_HEADER))
self.assertEqual(self.keylist.master_key.master_key, new_key)
self.assertEqual(self.keylist.database.database_key, new_key)
# Test an invalid KeyList management command raises CriticalError
with self.assertRaises(SystemExit):
self.keylist.manage(queues, 'invalid_key', None)
def main() -> None:
"""Derive master key, decrypt databases and initialize processes."""
os.chdir(sys.path[0])
check_kernel_version()
check_kernel_entropy()
operation, local_test, dd_sockets = process_arguments()
clear_screen()
c_print(TFC, head=1, tail=1)
master_key = MasterKey(operation, local_test)
settings = Settings(master_key, operation, local_test, dd_sockets)
contact_list = ContactList(master_key, settings)
key_list = KeyList(master_key, settings)
group_list = GroupList(master_key, settings, contact_list)
gateway = Gateway(settings)
if settings.software_operation == TX:
queues = {
MESSAGE_PACKET_QUEUE: Queue(),
FILE_PACKET_QUEUE: Queue(),
COMMAND_PACKET_QUEUE: Queue(),
NH_PACKET_QUEUE: Queue(),
LOG_PACKET_QUEUE: Queue(),
EXIT_QUEUE: Queue(),
NOISE_PACKET_QUEUE: Queue(),
NOISE_COMMAND_QUEUE: Queue(),
KEY_MANAGEMENT_QUEUE: Queue(),
WINDOW_SELECT_QUEUE: Queue()
}
process_list = [
Process(target=input_loop,
args=(queues, settings, gateway, contact_list, group_list,
master_key, sys.stdin.fileno())),
Process(target=sender_loop,
args=(queues, settings, gateway, key_list)),
Process(target=log_writer_loop, args=(queues, ))
]
if settings.session_traffic_masking:
process_list.extend([
Process(target=noise_loop,
args=(P_N_HEADER, queues[NOISE_PACKET_QUEUE],
contact_list)),
Process(target=noise_loop,
args=(C_N_HEADER, queues[NOISE_COMMAND_QUEUE]))
])
else:
queues = {
LOCAL_KEY_PACKET_HEADER: Queue(),
PUBLIC_KEY_PACKET_HEADER: Queue(),
MESSAGE_PACKET_HEADER: Queue(),
COMMAND_PACKET_HEADER: Queue(),
IMPORTED_FILE_HEADER: Queue(),
EXIT_QUEUE: Queue(),
GATEWAY_QUEUE: Queue()
}
process_list = [
Process(target=gateway_loop, args=(queues, gateway)),
Process(target=receiver_loop, args=(queues, settings)),
Process(target=output_loop,
args=(queues, settings, contact_list, key_list, group_list,
master_key, sys.stdin.fileno()))
]
for p in process_list:
p.start()
while True:
with ignored(EOFError, KeyboardInterrupt):
time.sleep(0.1)
if not all([p.is_alive() for p in process_list]):
for p in process_list:
p.terminate()
sys.exit(1)
if not queues[EXIT_QUEUE].empty():
command = queues[EXIT_QUEUE].get()
for p in process_list:
p.terminate()
if command == WIPE:
subprocess.Popen(
f"find {DIR_USER_DATA} -name '{operation}*' -type f -exec shred -n 3 -z -u {{}} \;",
shell=True).wait()
os.system('poweroff')
else:
sys.exit(0)
