diff options
| -rw-r--r-- | changelog.d/10232.bugfix | 1 | ||||
| -rw-r--r-- | synapse/events/utils.py | 5 | ||||
| -rw-r--r-- | synapse/events/validator.py | 77 | ||||
| -rw-r--r-- | synapse/python_dependencies.py | 3 | ||||
| -rw-r--r-- | tests/rest/client/test_power_levels.py | 78 |
5 files changed, 160 insertions, 4 deletions
diff --git a/changelog.d/10232.bugfix b/changelog.d/10232.bugfix new file mode 100644 index 0000000000..7be72271e0 --- /dev/null +++ b/changelog.d/10232.bugfix @@ -0,0 +1 @@ +Validate new `m.room.power_levels` events. Contributed by @aaronraimist. \ No newline at end of file diff --git a/synapse/events/utils.py b/synapse/events/utils.py index b6da2f60af..738a151cef 100644 --- a/synapse/events/utils.py +++ b/synapse/events/utils.py @@ -32,6 +32,9 @@ from . import EventBase # the literal fields "foo\" and "bar" but will instead be treated as "foo\\.bar" SPLIT_FIELD_REGEX = re.compile(r"(?<!\\)\.") +CANONICALJSON_MAX_INT = (2 ** 53) - 1 +CANONICALJSON_MIN_INT = -CANONICALJSON_MAX_INT + def prune_event(event: EventBase) -> EventBase: """Returns a pruned version of the given event, which removes all keys we @@ -505,7 +508,7 @@ def validate_canonicaljson(value: Any): * NaN, Infinity, -Infinity """ if isinstance(value, int): - if value <= -(2 ** 53) or 2 ** 53 <= value: + if value < CANONICALJSON_MIN_INT or CANONICALJSON_MAX_INT < value: raise SynapseError(400, "JSON integer out of range", Codes.BAD_JSON) elif isinstance(value, float): diff --git a/synapse/events/validator.py b/synapse/events/validator.py index fa6987d7cb..33954b4f62 100644 --- a/synapse/events/validator.py +++ b/synapse/events/validator.py @@ -11,16 +11,22 @@ # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. - +import collections.abc from typing import Union +import jsonschema + from synapse.api.constants import MAX_ALIAS_LENGTH, EventTypes, Membership from synapse.api.errors import Codes, SynapseError from synapse.api.room_versions import EventFormatVersions from synapse.config.homeserver import HomeServerConfig from synapse.events import EventBase from synapse.events.builder import EventBuilder -from synapse.events.utils import validate_canonicaljson +from synapse.events.utils import ( + CANONICALJSON_MAX_INT, + CANONICALJSON_MIN_INT, + validate_canonicaljson, +) from synapse.federation.federation_server import server_matches_acl_event from synapse.types import EventID, RoomID, UserID @@ -87,6 +93,29 @@ class EventValidator: 400, "Can't create an ACL event that denies the local server" ) + if event.type == EventTypes.PowerLevels: + try: + jsonschema.validate( + instance=event.content, + schema=POWER_LEVELS_SCHEMA, + cls=plValidator, + ) + except jsonschema.ValidationError as e: + if e.path: + # example: "users_default": '0' is not of type 'integer' + message = '"' + e.path[-1] + '": ' + e.message # noqa: B306 + # jsonschema.ValidationError.message is a valid attribute + else: + # example: '0' is not of type 'integer' + message = e.message # noqa: B306 + # jsonschema.ValidationError.message is a valid attribute + + raise SynapseError( + code=400, + msg=message, + errcode=Codes.BAD_JSON, + ) + def _validate_retention(self, event: EventBase): """Checks that an event that defines the retention policy for a room respects the format enforced by the spec. @@ -185,3 +214,47 @@ class EventValidator: def _ensure_state_event(self, event): if not event.is_state(): raise SynapseError(400, "'%s' must be state events" % (event.type,)) + + +POWER_LEVELS_SCHEMA = { + "type": "object", + "properties": { + "ban": {"$ref": "#/definitions/int"}, + "events": {"$ref": "#/definitions/objectOfInts"}, + "events_default": {"$ref": "#/definitions/int"}, + "invite": {"$ref": "#/definitions/int"}, + "kick": {"$ref": "#/definitions/int"}, + "notifications": {"$ref": "#/definitions/objectOfInts"}, + "redact": {"$ref": "#/definitions/int"}, + "state_default": {"$ref": "#/definitions/int"}, + "users": {"$ref": "#/definitions/objectOfInts"}, + "users_default": {"$ref": "#/definitions/int"}, + }, + "definitions": { + "int": { + "type": "integer", + "minimum": CANONICALJSON_MIN_INT, + "maximum": CANONICALJSON_MAX_INT, + }, + "objectOfInts": { + "type": "object", + "additionalProperties": {"$ref": "#/definitions/int"}, + }, + }, +} + + +def _create_power_level_validator(): + validator = jsonschema.validators.validator_for(POWER_LEVELS_SCHEMA) + + # by default jsonschema does not consider a frozendict to be an object so + # we need to use a custom type checker + # https://python-jsonschema.readthedocs.io/en/stable/validate/?highlight=object#validating-with-additional-types + type_checker = validator.TYPE_CHECKER.redefine( + "object", lambda checker, thing: isinstance(thing, collections.abc.Mapping) + ) + + return jsonschema.validators.extend(validator, type_checker=type_checker) + + +plValidator = _create_power_level_validator() diff --git a/synapse/python_dependencies.py b/synapse/python_dependencies.py index cdcbdd772b..154e5b7028 100644 --- a/synapse/python_dependencies.py +++ b/synapse/python_dependencies.py @@ -48,7 +48,8 @@ logger = logging.getLogger(__name__) # [1] https://pip.pypa.io/en/stable/reference/pip_install/#requirement-specifiers. REQUIREMENTS = [ - "jsonschema>=2.5.1", + # we use the TYPE_CHECKER.redefine method added in jsonschema 3.0.0 + "jsonschema>=3.0.0", "frozendict>=1", "unpaddedbase64>=1.1.0", "canonicaljson>=1.4.0", diff --git a/tests/rest/client/test_power_levels.py b/tests/rest/client/test_power_levels.py index 91d0762cb0..c0de4c93a8 100644 --- a/tests/rest/client/test_power_levels.py +++ b/tests/rest/client/test_power_levels.py @@ -12,6 +12,8 @@ # See the License for the specific language governing permissions and # limitations under the License. +from synapse.api.errors import Codes +from synapse.events.utils import CANONICALJSON_MAX_INT, CANONICALJSON_MIN_INT from synapse.rest import admin from synapse.rest.client import login, room, sync @@ -203,3 +205,79 @@ class PowerLevelsTestCase(HomeserverTestCase): tok=self.admin_access_token, expect_code=200, # expect success ) + + def test_cannot_set_string_power_levels(self): + room_power_levels = self.helper.get_state( + self.room_id, + "m.room.power_levels", + tok=self.admin_access_token, + ) + + # Update existing power levels with user at PL "0" + room_power_levels["users"].update({self.user_user_id: "0"}) + + body = self.helper.send_state( + self.room_id, + "m.room.power_levels", + room_power_levels, + tok=self.admin_access_token, + expect_code=400, # expect failure + ) + + self.assertEqual( + body["errcode"], + Codes.BAD_JSON, + body, + ) + + def test_cannot_set_unsafe_large_power_levels(self): + room_power_levels = self.helper.get_state( + self.room_id, + "m.room.power_levels", + tok=self.admin_access_token, + ) + + # Update existing power levels with user at PL above the max safe integer + room_power_levels["users"].update( + {self.user_user_id: CANONICALJSON_MAX_INT + 1} + ) + + body = self.helper.send_state( + self.room_id, + "m.room.power_levels", + room_power_levels, + tok=self.admin_access_token, + expect_code=400, # expect failure + ) + + self.assertEqual( + body["errcode"], + Codes.BAD_JSON, + body, + ) + + def test_cannot_set_unsafe_small_power_levels(self): + room_power_levels = self.helper.get_state( + self.room_id, + "m.room.power_levels", + tok=self.admin_access_token, + ) + + # Update existing power levels with user at PL below the minimum safe integer + room_power_levels["users"].update( + {self.user_user_id: CANONICALJSON_MIN_INT - 1} + ) + + body = self.helper.send_state( + self.room_id, + "m.room.power_levels", + room_power_levels, + tok=self.admin_access_token, + expect_code=400, # expect failure + ) + + self.assertEqual( + body["errcode"], + Codes.BAD_JSON, + body, + ) |