diff --git a/changelog.d/3641.bugfix b/changelog.d/3641.bugfix
new file mode 100644
index 0000000000..02181975c0
--- /dev/null
+++ b/changelog.d/3641.bugfix
@@ -0,0 +1 @@
+Fix a potential event disclosure issue
\ No newline at end of file
diff --git a/synapse/federation/federation_server.py b/synapse/federation/federation_server.py
index 48f26db67c..10e71c78ce 100644
--- a/synapse/federation/federation_server.py
+++ b/synapse/federation/federation_server.py
@@ -425,6 +425,7 @@ class FederationServer(FederationBase):
ret = yield self.handler.on_query_auth(
origin,
event_id,
+ room_id,
signed_auth,
content.get("rejects", []),
content.get("missing", []),
diff --git a/synapse/handlers/federation.py b/synapse/handlers/federation.py
index 20fb46fc89..60391d07c4 100644
--- a/synapse/handlers/federation.py
+++ b/synapse/handlers/federation.py
@@ -1349,6 +1349,11 @@ class FederationHandler(BaseHandler):
def get_state_for_pdu(self, room_id, event_id):
"""Returns the state at the event. i.e. not including said event.
"""
+
+ event = yield self.store.get_event(
+ event_id, allow_none=False, check_room_id=room_id,
+ )
+
state_groups = yield self.store.get_state_groups(
room_id, [event_id]
)
@@ -1359,8 +1364,7 @@ class FederationHandler(BaseHandler):
(e.type, e.state_key): e for e in state
}
- event = yield self.store.get_event(event_id)
- if event and event.is_state():
+ if event.is_state():
# Get previous state
if "replaces_state" in event.unsigned:
prev_id = event.unsigned["replaces_state"]
@@ -1391,6 +1395,10 @@ class FederationHandler(BaseHandler):
def get_state_ids_for_pdu(self, room_id, event_id):
"""Returns the state at the event. i.e. not including said event.
"""
+ event = yield self.store.get_event(
+ event_id, allow_none=False, check_room_id=room_id,
+ )
+
state_groups = yield self.store.get_state_groups_ids(
room_id, [event_id]
)
@@ -1399,8 +1407,7 @@ class FederationHandler(BaseHandler):
_, state = state_groups.items().pop()
results = state
- event = yield self.store.get_event(event_id)
- if event and event.is_state():
+ if event.is_state():
# Get previous state
if "replaces_state" in event.unsigned:
prev_id = event.unsigned["replaces_state"]
@@ -1706,8 +1713,19 @@ class FederationHandler(BaseHandler):
defer.returnValue(context)
@defer.inlineCallbacks
- def on_query_auth(self, origin, event_id, remote_auth_chain, rejects,
+ def on_query_auth(self, origin, event_id, room_id, remote_auth_chain, rejects,
missing):
+ in_room = yield self.auth.check_host_in_room(
+ room_id,
+ origin
+ )
+ if not in_room:
+ raise AuthError(403, "Host not in room.")
+
+ event = yield self.store.get_event(
+ event_id, allow_none=False, check_room_id=room_id
+ )
+
# Just go through and process each event in `remote_auth_chain`. We
# don't want to fall into the trap of `missing` being wrong.
for e in remote_auth_chain:
@@ -1717,7 +1735,6 @@ class FederationHandler(BaseHandler):
pass
# Now get the current auth_chain for the event.
- event = yield self.store.get_event(event_id)
local_auth_chain = yield self.store.get_auth_chain(
[auth_id for auth_id, _ in event.auth_events],
include_given=True
diff --git a/synapse/storage/event_federation.py b/synapse/storage/event_federation.py
index 8d366d1b91..7cd77c1c29 100644
--- a/synapse/storage/event_federation.py
+++ b/synapse/storage/event_federation.py
@@ -343,6 +343,7 @@ class EventFederationWorkerStore(EventsWorkerStore, SignatureWorkerStore,
table="events",
keyvalues={
"event_id": event_id,
+ "room_id": room_id,
},
retcol="depth",
allow_none=True,
diff --git a/synapse/storage/events_worker.py b/synapse/storage/events_worker.py
index 67433606c6..6b8a8e908f 100644
--- a/synapse/storage/events_worker.py
+++ b/synapse/storage/events_worker.py
@@ -19,7 +19,7 @@ from canonicaljson import json
from twisted.internet import defer
-from synapse.api.errors import SynapseError
+from synapse.api.errors import NotFoundError
# these are only included to make the type annotations work
from synapse.events import EventBase # noqa: F401
from synapse.events import FrozenEvent
@@ -76,7 +76,7 @@ class EventsWorkerStore(SQLBaseStore):
@defer.inlineCallbacks
def get_event(self, event_id, check_redacted=True,
get_prev_content=False, allow_rejected=False,
- allow_none=False):
+ allow_none=False, check_room_id=None):
"""Get an event from the database by event_id.
Args:
@@ -87,7 +87,9 @@ class EventsWorkerStore(SQLBaseStore):
include the previous states content in the unsigned field.
allow_rejected (bool): If True return rejected events.
allow_none (bool): If True, return None if no event found, if
- False throw an exception.
+ False throw a NotFoundError
+ check_room_id (str|None): if not None, check the room of the found event.
+ If there is a mismatch, behave as per allow_none.
Returns:
Deferred : A FrozenEvent.
@@ -99,10 +101,16 @@ class EventsWorkerStore(SQLBaseStore):
allow_rejected=allow_rejected,
)
- if not events and not allow_none:
- raise SynapseError(404, "Could not find event %s" % (event_id,))
+ event = events[0] if events else None
- defer.returnValue(events[0] if events else None)
+ if event is not None and check_room_id is not None:
+ if event.room_id != check_room_id:
+ event = None
+
+ if event is None and not allow_none:
+ raise NotFoundError("Could not find event %s" % (event_id,))
+
+ defer.returnValue(event)
@defer.inlineCallbacks
def get_events(self, event_ids, check_redacted=True,
|