289 lines
11 KiB
Python
289 lines
11 KiB
Python
# Copyright 2014-2016 OpenMarket Ltd
|
|
#
|
|
# Licensed under the Apache License, Version 2.0 (the "License");
|
|
# you may not use this file except in compliance with the License.
|
|
# You may obtain a copy of the License at
|
|
#
|
|
# http://www.apache.org/licenses/LICENSE-2.0
|
|
#
|
|
# Unless required by applicable law or agreed to in writing, software
|
|
# distributed under the License is distributed on an "AS IS" BASIS,
|
|
# 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 Iterable, List, Type, Union, cast
|
|
|
|
import jsonschema
|
|
from pydantic import Field, StrictBool, StrictStr
|
|
|
|
from synapse.api.constants import (
|
|
MAX_ALIAS_LENGTH,
|
|
EventContentFields,
|
|
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 (
|
|
CANONICALJSON_MAX_INT,
|
|
CANONICALJSON_MIN_INT,
|
|
validate_canonicaljson,
|
|
)
|
|
from synapse.federation.federation_server import server_matches_acl_event
|
|
from synapse.http.servlet import validate_json_object
|
|
from synapse.rest.models import RequestBodyModel
|
|
from synapse.types import EventID, JsonDict, RoomID, UserID
|
|
|
|
|
|
class EventValidator:
|
|
def validate_new(self, event: EventBase, config: HomeServerConfig) -> None:
|
|
"""Validates the event has roughly the right format
|
|
|
|
Suitable for checking a locally-created event. It has stricter checks than
|
|
is appropriate for an event received over federation (for which, see
|
|
event_auth.validate_event_for_room_version)
|
|
|
|
Args:
|
|
event: The event to validate.
|
|
config: The homeserver's configuration.
|
|
"""
|
|
self.validate_builder(event)
|
|
|
|
if event.format_version == EventFormatVersions.ROOM_V1_V2:
|
|
EventID.from_string(event.event_id)
|
|
|
|
required = [
|
|
"auth_events",
|
|
"content",
|
|
"hashes",
|
|
"origin",
|
|
"prev_events",
|
|
"sender",
|
|
"type",
|
|
]
|
|
|
|
for k in required:
|
|
if k not in event:
|
|
raise SynapseError(400, "Event does not have key %s" % (k,))
|
|
|
|
# Check that the following keys have string values
|
|
event_strings = ["origin"]
|
|
|
|
for s in event_strings:
|
|
if not isinstance(getattr(event, s), str):
|
|
raise SynapseError(400, "'%s' not a string type" % (s,))
|
|
|
|
# Depending on the room version, ensure the data is spec compliant JSON.
|
|
if event.room_version.strict_canonicaljson:
|
|
# Note that only the client controlled portion of the event is
|
|
# checked, since we trust the portions of the event we created.
|
|
validate_canonicaljson(event.content)
|
|
|
|
if event.type == EventTypes.Aliases:
|
|
if "aliases" in event.content:
|
|
for alias in event.content["aliases"]:
|
|
if len(alias) > MAX_ALIAS_LENGTH:
|
|
raise SynapseError(
|
|
400,
|
|
(
|
|
"Can't create aliases longer than"
|
|
" %d characters" % (MAX_ALIAS_LENGTH,)
|
|
),
|
|
Codes.INVALID_PARAM,
|
|
)
|
|
|
|
elif event.type == EventTypes.Retention:
|
|
self._validate_retention(event)
|
|
|
|
elif event.type == EventTypes.ServerACL:
|
|
if not server_matches_acl_event(config.server.server_name, event):
|
|
raise SynapseError(
|
|
400, "Can't create an ACL event that denies the local server"
|
|
)
|
|
|
|
elif event.type == EventTypes.PowerLevels:
|
|
try:
|
|
jsonschema.validate(
|
|
instance=event.content,
|
|
schema=POWER_LEVELS_SCHEMA,
|
|
cls=POWER_LEVELS_VALIDATOR,
|
|
)
|
|
except jsonschema.ValidationError as e:
|
|
if e.path:
|
|
# example: "users_default": '0' is not of type 'integer'
|
|
# cast safety: path entries can be integers, if we fail to validate
|
|
# items in an array. However, the POWER_LEVELS_SCHEMA doesn't expect
|
|
# to see any arrays.
|
|
message = (
|
|
'"' + cast(str, 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,
|
|
)
|
|
|
|
# If the event contains a mentions key, validate it.
|
|
if EventContentFields.MENTIONS in event.content:
|
|
validate_json_object(event.content[EventContentFields.MENTIONS], Mentions)
|
|
|
|
def _validate_retention(self, event: EventBase) -> None:
|
|
"""Checks that an event that defines the retention policy for a room respects the
|
|
format enforced by the spec.
|
|
|
|
Args:
|
|
event: The event to validate.
|
|
"""
|
|
if not event.is_state():
|
|
raise SynapseError(code=400, msg="must be a state event")
|
|
|
|
min_lifetime = event.content.get("min_lifetime")
|
|
max_lifetime = event.content.get("max_lifetime")
|
|
|
|
if min_lifetime is not None:
|
|
if type(min_lifetime) is not int: # noqa: E721
|
|
raise SynapseError(
|
|
code=400,
|
|
msg="'min_lifetime' must be an integer",
|
|
errcode=Codes.BAD_JSON,
|
|
)
|
|
|
|
if max_lifetime is not None:
|
|
if type(max_lifetime) is not int: # noqa: E721
|
|
raise SynapseError(
|
|
code=400,
|
|
msg="'max_lifetime' must be an integer",
|
|
errcode=Codes.BAD_JSON,
|
|
)
|
|
|
|
if (
|
|
min_lifetime is not None
|
|
and max_lifetime is not None
|
|
and min_lifetime > max_lifetime
|
|
):
|
|
raise SynapseError(
|
|
code=400,
|
|
msg="'min_lifetime' can't be greater than 'max_lifetime",
|
|
errcode=Codes.BAD_JSON,
|
|
)
|
|
|
|
def validate_builder(self, event: Union[EventBase, EventBuilder]) -> None:
|
|
"""Validates that the builder/event has roughly the right format. Only
|
|
checks values that we expect a proto event to have, rather than all the
|
|
fields an event would have
|
|
"""
|
|
|
|
strings = ["room_id", "sender", "type"]
|
|
|
|
if hasattr(event, "state_key"):
|
|
strings.append("state_key")
|
|
|
|
for s in strings:
|
|
if not isinstance(getattr(event, s), str):
|
|
raise SynapseError(400, "Not '%s' a string type" % (s,))
|
|
|
|
RoomID.from_string(event.room_id)
|
|
UserID.from_string(event.sender)
|
|
|
|
if event.type == EventTypes.Message:
|
|
strings = ["body", "msgtype"]
|
|
|
|
self._ensure_strings(event.content, strings)
|
|
|
|
elif event.type == EventTypes.Topic:
|
|
self._ensure_strings(event.content, ["topic"])
|
|
self._ensure_state_event(event)
|
|
elif event.type == EventTypes.Name:
|
|
self._ensure_strings(event.content, ["name"])
|
|
self._ensure_state_event(event)
|
|
elif event.type == EventTypes.Member:
|
|
if "membership" not in event.content:
|
|
raise SynapseError(400, "Content has not membership key")
|
|
|
|
if event.content["membership"] not in Membership.LIST:
|
|
raise SynapseError(400, "Invalid membership key")
|
|
|
|
self._ensure_state_event(event)
|
|
elif event.type == EventTypes.Tombstone:
|
|
if "replacement_room" not in event.content:
|
|
raise SynapseError(400, "Content has no replacement_room key")
|
|
|
|
if event.content["replacement_room"] == event.room_id:
|
|
raise SynapseError(
|
|
400, "Tombstone cannot reference the room it was sent in"
|
|
)
|
|
|
|
self._ensure_state_event(event)
|
|
|
|
def _ensure_strings(self, d: JsonDict, keys: Iterable[str]) -> None:
|
|
for s in keys:
|
|
if s not in d:
|
|
raise SynapseError(400, "'%s' not in content" % (s,))
|
|
if not isinstance(d[s], str):
|
|
raise SynapseError(400, "'%s' not a string type" % (s,))
|
|
|
|
def _ensure_state_event(self, event: Union[EventBase, EventBuilder]) -> None:
|
|
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"},
|
|
},
|
|
},
|
|
}
|
|
|
|
|
|
class Mentions(RequestBodyModel):
|
|
user_ids: List[StrictStr] = Field(default_factory=list)
|
|
room: StrictBool = False
|
|
|
|
|
|
# This could return something newer than Draft 7, but that's the current "latest"
|
|
# validator.
|
|
def _create_validator(schema: JsonDict) -> Type[jsonschema.Draft7Validator]:
|
|
validator = jsonschema.validators.validator_for(schema)
|
|
|
|
# by default jsonschema does not consider a immutabledict 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)
|
|
|
|
|
|
POWER_LEVELS_VALIDATOR = _create_validator(POWER_LEVELS_SCHEMA)
|