Reject events which are too large

SPEC-222
This commit is contained in:
Daniel Wagner-Hall 2015-10-22 11:44:31 +01:00
parent 8627048787
commit e60dad86ba
2 changed files with 30 additions and 1 deletions

View File

@ -14,13 +14,14 @@
# limitations under the License.
"""This module contains classes for authenticating the user."""
from canonicaljson import encode_canonical_json
from signedjson.key import decode_verify_key_bytes
from signedjson.sign import verify_signed_json, SignatureVerifyException
from twisted.internet import defer
from synapse.api.constants import EventTypes, Membership, JoinRules
from synapse.api.errors import AuthError, Codes, SynapseError
from synapse.api.errors import AuthError, Codes, SynapseError, EventSizeError
from synapse.types import RoomID, UserID, EventID
from synapse.util.logutils import log_function
from synapse.util import third_party_invites
@ -64,6 +65,8 @@ class Auth(object):
Returns:
True if the auth checks pass.
"""
self.check_size_limits(event)
try:
if not hasattr(event, "room_id"):
raise AuthError(500, "Event has no room_id: %s" % event)
@ -131,6 +134,23 @@ class Auth(object):
logger.info("Denying! %s", event)
raise
def check_size_limits(self, event):
def too_big(field):
raise EventSizeError("%s too large" % (field,))
if len(event.user_id) > 255:
too_big("user_id")
if len(event.room_id) > 255:
too_big("room_id")
if event.is_state() and len(event.state_key) > 255:
too_big("state_key")
if len(event.type) > 255:
too_big("type")
if len(event.event_id) > 255:
too_big("event_id")
if len(encode_canonical_json(event.get_pdu_json())) > 65536:
too_big("event")
@defer.inlineCallbacks
def check_joined_room(self, room_id, user_id, current_state=None):
"""Check if the user is currently joined in the room

View File

@ -119,6 +119,15 @@ class AuthError(SynapseError):
super(AuthError, self).__init__(*args, **kwargs)
class EventSizeError(SynapseError):
"""An error raised when an event is too big."""
def __init__(self, *args, **kwargs):
if "errcode" not in kwargs:
kwargs["errcode"] = Codes.TOO_LARGE
super(EventSizeError, self).__init__(413, *args, **kwargs)
class EventStreamError(SynapseError):
"""An error raised when there a problem with the event stream."""
def __init__(self, *args, **kwargs):