diff options
Diffstat (limited to 'synapse/event_auth.py')
| -rw-r--r-- | synapse/event_auth.py | 130 |
1 files changed, 83 insertions, 47 deletions
diff --git a/synapse/event_auth.py b/synapse/event_auth.py index eaf9cecde6..6baeccca38 100644 --- a/synapse/event_auth.py +++ b/synapse/event_auth.py @@ -17,11 +17,11 @@ import logging from canonicaljson import encode_canonical_json from signedjson.key import decode_verify_key_bytes -from signedjson.sign import verify_signed_json, SignatureVerifyException +from signedjson.sign import SignatureVerifyException, verify_signed_json from unpaddedbase64 import decode_base64 -from synapse.api.constants import EventTypes, Membership, JoinRules -from synapse.api.errors import AuthError, SynapseError, EventSizeError +from synapse.api.constants import KNOWN_ROOM_VERSIONS, EventTypes, JoinRules, Membership +from synapse.api.errors import AuthError, EventSizeError, SynapseError from synapse.types import UserID, get_domain_from_id logger = logging.getLogger(__name__) @@ -34,9 +34,11 @@ def check(event, auth_events, do_sig_check=True, do_size_check=True): event: the event being checked. auth_events (dict: event-key -> event): the existing room state. + Raises: + AuthError if the checks fail Returns: - True if the auth checks pass. + if the auth checks pass. """ if do_size_check: _check_size_limits(event) @@ -71,17 +73,27 @@ def check(event, auth_events, do_sig_check=True, do_size_check=True): # Oh, we don't know what the state of the room was, so we # are trusting that this is allowed (at least for now) logger.warn("Trusting event: %s", event.event_id) - return True + return if event.type == EventTypes.Create: + sender_domain = get_domain_from_id(event.sender) room_id_domain = get_domain_from_id(event.room_id) if room_id_domain != sender_domain: raise AuthError( 403, "Creation event's room_id domain does not match sender's" ) + + room_version = event.content.get("room_version", "1") + if room_version not in KNOWN_ROOM_VERSIONS: + raise AuthError( + 403, + "room appears to have unsupported version %s" % ( + room_version, + )) # FIXME - return True + logger.debug("Allowing! %s", event) + return creation_event = auth_events.get((EventTypes.Create, ""), None) @@ -118,7 +130,8 @@ def check(event, auth_events, do_sig_check=True, do_size_check=True): 403, "Alias event's state_key does not match sender's domain" ) - return True + logger.debug("Allowing! %s", event) + return if logger.isEnabledFor(logging.DEBUG): logger.debug( @@ -127,14 +140,9 @@ def check(event, auth_events, do_sig_check=True, do_size_check=True): ) if event.type == EventTypes.Member: - allowed = _is_membership_change_allowed( - event, auth_events - ) - if allowed: - logger.debug("Allowing! %s", event) - else: - logger.debug("Denying! %s", event) - return allowed + _is_membership_change_allowed(event, auth_events) + logger.debug("Allowing! %s", event) + return _check_event_sender_in_room(event, auth_events) @@ -153,7 +161,8 @@ def check(event, auth_events, do_sig_check=True, do_size_check=True): ) ) else: - return True + logger.debug("Allowing! %s", event) + return _can_send_event(event, auth_events) @@ -200,7 +209,7 @@ def _is_membership_change_allowed(event, auth_events): create = auth_events.get(key) if create and event.prev_events[0][0] == create.event_id: if create.content["creator"] == event.state_key: - return True + return target_user_id = event.state_key @@ -265,13 +274,13 @@ def _is_membership_change_allowed(event, auth_events): raise AuthError( 403, "%s is banned from the room" % (target_user_id,) ) - return True + return if Membership.JOIN != membership: if (caller_invited and Membership.LEAVE == membership and target_user_id == event.user_id): - return True + return if not caller_in_room: # caller isn't joined raise AuthError( @@ -334,8 +343,6 @@ def _is_membership_change_allowed(event, auth_events): else: raise AuthError(500, "Unknown membership %s" % membership) - return True - def _check_event_sender_in_room(event, auth_events): key = (EventTypes.Member, event.user_id, ) @@ -355,35 +362,46 @@ def _check_joined_room(member, user_id, room_id): )) -def get_send_level(etype, state_key, auth_events): - key = (EventTypes.PowerLevels, "", ) - send_level_event = auth_events.get(key) - send_level = None - if send_level_event: - send_level = send_level_event.content.get("events", {}).get( - etype - ) - if send_level is None: - if state_key is not None: - send_level = send_level_event.content.get( - "state_default", 50 - ) - else: - send_level = send_level_event.content.get( - "events_default", 0 - ) +def get_send_level(etype, state_key, power_levels_event): + """Get the power level required to send an event of a given type + + The federation spec [1] refers to this as "Required Power Level". + + https://matrix.org/docs/spec/server_server/unstable.html#definitions - if send_level: - send_level = int(send_level) + Args: + etype (str): type of event + state_key (str|None): state_key of state event, or None if it is not + a state event. + power_levels_event (synapse.events.EventBase|None): power levels event + in force at this point in the room + Returns: + int: power level required to send this event. + """ + + if power_levels_event: + power_levels_content = power_levels_event.content else: - send_level = 0 + power_levels_content = {} + + # see if we have a custom level for this event type + send_level = power_levels_content.get("events", {}).get(etype) - return send_level + # otherwise, fall back to the state_default/events_default. + if send_level is None: + if state_key is not None: + send_level = power_levels_content.get("state_default", 50) + else: + send_level = power_levels_content.get("events_default", 0) + + return int(send_level) def _can_send_event(event, auth_events): + power_levels_event = _get_power_level_event(auth_events) + send_level = get_send_level( - event.type, event.get("state_key", None), auth_events + event.type, event.get("state_key"), power_levels_event, ) user_level = get_user_power_level(event.user_id, auth_events) @@ -515,7 +533,11 @@ def _check_power_levels(event, auth_events): "to your own" ) - if old_level > user_level or new_level > user_level: + # Check if the old and new levels are greater than the user level + # (if defined) + old_level_too_big = old_level is not None and old_level > user_level + new_level_too_big = new_level is not None and new_level > user_level + if old_level_too_big or new_level_too_big: raise AuthError( 403, "You don't have permission to add ops level greater " @@ -524,13 +546,22 @@ def _check_power_levels(event, auth_events): def _get_power_level_event(auth_events): - key = (EventTypes.PowerLevels, "", ) - return auth_events.get(key) + return auth_events.get((EventTypes.PowerLevels, "")) def get_user_power_level(user_id, auth_events): - power_level_event = _get_power_level_event(auth_events) + """Get a user's power level + + Args: + user_id (str): user's id to look up in power_levels + auth_events (dict[(str, str), synapse.events.EventBase]): + state in force at this point in the room (or rather, a subset of + it including at least the create event and power levels event. + Returns: + int: the user's power level in this room. + """ + power_level_event = _get_power_level_event(auth_events) if power_level_event: level = power_level_event.content.get("users", {}).get(user_id) if not level: @@ -541,6 +572,11 @@ def get_user_power_level(user_id, auth_events): else: return int(level) else: + # if there is no power levels event, the creator gets 100 and everyone + # else gets 0. + + # some things which call this don't pass the create event: hack around + # that. key = (EventTypes.Create, "", ) create_event = auth_events.get(key) if (create_event is not None and |