def revoke_user(self, user, author_rand):
possible_authors = [
device
for device_id, device in self.local_devices.items()
if device_id.user_id != user and device.profile == UserProfile.ADMIN
]
author = possible_authors[author_rand % len(possible_authors)]
note(f"revoke user: {user} (author: {author.device_id})")
revoked_user = RevokedUserCertificateContent(
author=author.device_id, timestamp=pendulum_now(), user_id=user
)
self.revoked_users_content[user] = revoked_user
self.revoked_users_certifs[user] = revoked_user.dump_and_sign(author.signing_key)
return user
async def api_user_revoke(self, client_ctx, msg):
if client_ctx.profile != UserProfile.ADMIN:
return {
"status": "not_allowed",
"reason":
f"User `{client_ctx.device_id.user_id}` is not admin",
}
msg = user_revoke_serializer.req_load(msg)
try:
data = RevokedUserCertificateContent.verify_and_load(
msg["revoked_user_certificate"],
author_verify_key=client_ctx.verify_key,
expected_author=client_ctx.device_id,
)
except DataError as exc:
return {
"status": "invalid_certification",
"reason": f"Invalid certification data ({exc}).",
}
if not timestamps_in_the_ballpark(data.timestamp, pendulum.now()):
return {
"status": "invalid_certification",
"reason": "Invalid timestamp in certification.",
}
if data.user_id == client_ctx.user_id:
return {
"status": "not_allowed",
"reason": "Cannot do self-revocation"
}
try:
await self.revoke_user(
organization_id=client_ctx.organization_id,
user_id=data.user_id,
revoked_user_certificate=msg["revoked_user_certificate"],
revoked_user_certifier=data.author,
revoked_on=data.timestamp,
)
except UserNotFoundError:
return {"status": "not_found"}
except UserAlreadyRevokedError:
return {
"status": "already_revoked",
"reason": f"User `{data.user_id}` already revoked"
}
return user_revoke_serializer.rep_dump({"status": "ok"})
async def bind_revocation(self, user_id: UserID,
certifier: LocalDevice):
revoked_user_certificate = RevokedUserCertificateContent(
author=certifier.device_id,
timestamp=pendulum.now(),
user_id=user_id).dump_and_sign(certifier.signing_key)
await self.backend.user.revoke_user(certifier.organization_id,
user_id,
revoked_user_certificate,
certifier.device_id)
self.certificates_store.store_revoked_user(
certifier.organization_id, user_id, revoked_user_certificate)
async def test_handshake_revoked_device(running_backend, alice, bob):
revoked_user_certificate = RevokedUserCertificateContent(
author=alice.device_id, timestamp=pendulum.now(), user_id=bob.user_id
).dump_and_sign(alice.signing_key)
await running_backend.backend.user.revoke_user(
organization_id=alice.organization_id,
user_id=bob.user_id,
revoked_user_certificate=revoked_user_certificate,
revoked_user_certifier=alice.device_id,
)
with pytest.raises(BackendConnectionRefused) as exc:
async with backend_authenticated_cmds_factory(
bob.organization_addr, bob.device_id, bob.signing_key
) as cmds:
await cmds.ping()
assert str(exc.value) == "Device has been revoked"
async def revoke_user(self, user_id: UserID) -> None:
"""
Raises:
BackendConnectionError
"""
now = pendulum_now()
revoked_user_certificate = RevokedUserCertificateContent(
author=self.device.device_id, timestamp=now,
user_id=user_id).dump_and_sign(self.device.signing_key)
rep = await self._backend_conn.cmds.user_revoke(
revoked_user_certificate=revoked_user_certificate)
if rep["status"] != "ok":
raise BackendConnectionError(
f"Error while trying to revoke user {user_id}: {rep}")
# Invalidate potential cache to avoid displaying the user as not-revoked
self._remote_devices_manager.invalidate_user_cache(user_id)
def test_build_revoked_user_certificate(alice, bob, mallory):
now = pendulum_now()
certif = RevokedUserCertificateContent(
author=alice.device_id, timestamp=now, user_id=bob.user_id
).dump_and_sign(alice.signing_key)
assert isinstance(certif, bytes)
unsecure = RevokedUserCertificateContent.unsecure_load(certif)
assert isinstance(unsecure, RevokedUserCertificateContent)
assert unsecure.user_id == bob.user_id
assert unsecure.timestamp == now
assert unsecure.author == alice.device_id
verified = RevokedUserCertificateContent.verify_and_load(
certif, author_verify_key=alice.verify_key, expected_author=alice.device_id
)
assert verified == unsecure
with pytest.raises(DataError) as exc:
RevokedUserCertificateContent.verify_and_load(
certif, author_verify_key=alice.verify_key, expected_author=mallory.device_id
)
assert str(exc.value) == "Invalid author: expected `mallory@dev1`, got `alice@dev1`"
with pytest.raises(DataError) as exc:
RevokedUserCertificateContent.verify_and_load(
certif, author_verify_key=mallory.verify_key, expected_author=alice.device_id
)
assert str(exc.value) == "Signature was forged or corrupt"
with pytest.raises(DataError) as exc:
RevokedUserCertificateContent.verify_and_load(
certif,
author_verify_key=alice.verify_key,
expected_author=alice.device_id,
expected_user=mallory.user_id,
)
assert str(exc.value) == "Invalid user ID: expected `mallory`, got `bob`"
def load_trustchain(
self,
users: Sequence[bytes] = (),
revoked_users: Sequence[bytes] = (),
devices: Sequence[bytes] = (),
now: DateTime = None,
) -> Tuple[List[UserCertificateContent],
List[RevokedUserCertificateContent],
List[DeviceCertificateContent], ]:
now = now or pendulum_now()
users_states = {}
devices_states = {}
revoked_users_states = {}
# Deserialize the certificates and filter the ones we already have in cache
try:
for certif in devices:
unverified_device = DeviceCertificateContent.unsecure_load(
certif)
verified_device = self.get_device(unverified_device.device_id,
now)
if verified_device:
devices_states[verified_device.device_id] = CertifState(
certif, verified_device, True)
else:
devices_states[unverified_device.device_id] = CertifState(
certif, unverified_device, False)
for certif in users:
unverified_user = UserCertificateContent.unsecure_load(certif)
verified_user = self.get_user(unverified_user.user_id, now)
if verified_user:
users_states[verified_user.user_id] = CertifState(
certif, verified_user, True)
else:
users_states[unverified_user.user_id] = CertifState(
certif, unverified_user, False)
for certif in revoked_users:
unverified_revoked_user = RevokedUserCertificateContent.unsecure_load(
certif)
verified_revoked_user = self.get_revoked_user(
unverified_revoked_user.user_id, now)
if verified_revoked_user:
revoked_users_states[
verified_revoked_user.user_id] = CertifState(
certif, verified_revoked_user, True)
else:
revoked_users_states[
unverified_revoked_user.user_id] = CertifState(
certif, unverified_revoked_user, False)
except DataError as exc:
raise TrustchainError(f"Invalid certificate: {exc}") from exc
def _get_eventually_verified_user(user_id):
try:
return users_states[user_id].content
except KeyError:
return None
def _get_eventually_verified_revoked_user(user_id):
try:
return revoked_users_states[user_id].content
except KeyError:
return None
def _verify_created_by_root(certif, certif_cls, sign_chain):
try:
return certif_cls.verify_and_load(
certif,
author_verify_key=self.root_verify_key,
expected_author=None)
except DataError as exc:
path = _build_signature_path(*sign_chain, "<Root Key>")
raise TrustchainError(
f"{path}: Invalid certificate: {exc}") from exc
def _verify_created_by_device(certif, certif_cls, author_id,
sign_chain):
author_device = _recursive_verify_device(author_id, sign_chain)
try:
verified = certif_cls.verify_and_load(
certif,
author_verify_key=author_device.verify_key,
expected_author=author_device.device_id,
)
except DataError as exc:
path = _build_signature_path(*sign_chain, author_id)
raise TrustchainError(
f"{path}: Invalid certificate: {exc}") from exc
# Author is either admin or signing one of it own devices
verified_user_id = (verified.device_id.user_id if isinstance(
verified, DeviceCertificateContent) else verified.user_id)
if author_device.device_id.user_id != verified_user_id:
author_user = _get_eventually_verified_user(author_id.user_id)
if not author_user:
path = _build_signature_path(*sign_chain, author_id)
raise TrustchainError(
f"{path}: Missing user certificate for {author_id.user_id}"
)
elif author_user.profile != UserProfile.ADMIN:
path = _build_signature_path(*sign_chain, author_id)
raise TrustchainError(
f"{path}: Invalid signature given {author_user.user_id} is not admin"
)
# Also make sure author wasn't revoked at creation time
author_revoked_user = _get_eventually_verified_revoked_user(
author_id.user_id)
if author_revoked_user and verified.timestamp > author_revoked_user.timestamp:
path = _build_signature_path(*sign_chain, author_id)
raise TrustchainError(
f"{path}: Signature ({verified.timestamp}) is posterior "
f"to user revocation ({author_revoked_user.timestamp})")
return verified
def _recursive_verify_device(device_id, signed_children=()):
if device_id in signed_children:
path = _build_signature_path(*signed_children, device_id)
raise TrustchainError(
f"{path}: Invalid signature loop detected")
try:
state = devices_states[device_id]
except KeyError:
path = _build_signature_path(*signed_children, device_id)
raise TrustchainError(
f"{path}: Missing device certificate for {device_id}")
author = state.content.author
if author is None:
verified_device = _verify_created_by_root(
state.certif,
DeviceCertificateContent,
sign_chain=(*signed_children, device_id))
else:
verified_device = _verify_created_by_device(
state.certif,
DeviceCertificateContent,
author,
sign_chain=(*signed_children, device_id),
)
return verified_device
def _verify_user(unverified_content, certif):
author = unverified_content.author
user_id = unverified_content.user_id
if author is None:
verified_user = _verify_created_by_root(
certif,
UserCertificateContent,
sign_chain=(f"{user_id}'s creation", ))
elif author.user_id == user_id:
raise TrustchainError(
f"{user_id}: Invalid self-signed user certificate")
else:
verified_user = _verify_created_by_device(
certif,
UserCertificateContent,
author,
sign_chain=(f"{user_id}'s creation", ))
return verified_user
def _verify_revoked_user(unverified_content, certif):
author = unverified_content.author
user_id = unverified_content.user_id
if author is None:
verified_revoked_user = _verify_created_by_root(
certif,
RevokedUserCertificateContent,
sign_chain=(f"{user_id}'s revocation", ))
elif author.user_id == user_id:
raise TrustchainError(
f"{user_id}: Invalid self-signed user revocation certificate"
)
else:
verified_revoked_user = _verify_created_by_device(
certif,
RevokedUserCertificateContent,
author,
sign_chain=(f"{user_id}'s revocation", ),
)
return verified_revoked_user
# Verified what need to be and populate the cache with them
for certif_state in devices_states.values():
if not certif_state.verified:
certif_state.content = _recursive_verify_device(
certif_state.content.device_id)
for certif_state in users_states.values():
if not certif_state.verified:
certif_state.content = _verify_user(certif_state.content,
certif_state.certif)
for certif_state in revoked_users_states.values():
if not certif_state.verified:
certif_state.content = _verify_revoked_user(
certif_state.content, certif_state.certif)
# Finally populate the cache
for certif_state in devices_states.values():
if not certif_state.verified:
self._devices_cache[certif_state.content.device_id] = (
now, certif_state.content)
for certif_state in users_states.values():
if not certif_state.verified:
self._users_cache[certif_state.content.user_id] = (
now, certif_state.content)
for certif_state in revoked_users_states.values():
if not certif_state.verified:
self._revoked_users_cache[certif_state.content.user_id] = (
now,
certif_state.content,
)
return (
[state.content for state in users_states.values()],
[state.content for state in revoked_users_states.values()],
[state.content for state in devices_states.values()],
)
def _trustchain_data_factory(todo_devices, todo_users):
data = TrustchainData(coolorg.organization_id, coolorg.root_verify_key)
def _get_certifier_id_and_key(certifier):
if not certifier:
# Certified by root
certifier_id = None
certifier_key = coolorg.root_signing_key
else:
certifier_ld = data.get_local_device(certifier)
if not certifier_ld:
raise RuntimeError(f"Missing `{certifier}` to sign creation of `{todo_device}`")
certifier_id = certifier_ld.device_id
certifier_key = certifier_ld.signing_key
return certifier_id, certifier_key
# First create all the devices
for todo_device in todo_devices:
local_device = local_device_factory(todo_device["id"], org=coolorg)
data.add_local_device(local_device)
# Generate device certificate
certifier_id, certifier_key = _get_certifier_id_and_key(todo_device.get("certifier"))
created_on = todo_device.get("created_on", now)
device_certificate = DeviceCertificateContent(
author=certifier_id,
timestamp=created_on,
device_id=local_device.device_id,
device_label=local_device.device_label,
verify_key=local_device.verify_key,
)
data.add_device_certif(
device_certificate, device_certificate.dump_and_sign(certifier_key)
)
# Now deal with the users
for todo_user in todo_users:
local_user = next(
(u for u in data.local_devices.values() if str(u.user_id) == todo_user["id"]), None
)
if not local_user:
raise RuntimeError(f"Missing device for user `{todo_user['id']}`")
# Generate user certificate
certifier_id, certifier_key = _get_certifier_id_and_key(todo_user.get("certifier"))
created_on = todo_user.get("created_on", now)
user_certif = UserCertificateContent(
author=certifier_id,
timestamp=created_on,
user_id=local_user.user_id,
human_handle=local_device.human_handle,
public_key=local_user.public_key,
profile=todo_user.get("profile", UserProfile.STANDARD),
)
data.add_user_certif(user_certif, user_certif.dump_and_sign(certifier_key))
# Generate user revocation certificate if needed
revoker = todo_user.get("revoker", None)
if revoker:
revoked_on = todo_user.get("revoked_on", now)
revoker_ld = data.get_local_device(revoker)
if not revoker_ld:
raise RuntimeError(
f"Missing `{revoker}` to sign revocation of `{todo_user['id']}`"
)
revoked_user_certificate = RevokedUserCertificateContent(
author=revoker_ld.device_id, timestamp=revoked_on, user_id=local_user.user_id
)
data.add_revoked_user_certif(
revoked_user_certificate,
revoked_user_certificate.dump_and_sign(revoker_ld.signing_key),
)
return data
def test_unsecure_read_revoked_user_certificate_bad_data():
with pytest.raises(DataError):
RevokedUserCertificateContent.unsecure_load(b"dummy")