diff --git a/changelog.d/9258.feature b/changelog.d/9258.feature
new file mode 100644
index 0000000000..0028f42d26
--- /dev/null
+++ b/changelog.d/9258.feature
@@ -0,0 +1 @@
+Add ratelimits to invites in rooms and to specific users.
diff --git a/docs/sample_config.yaml b/docs/sample_config.yaml
index 332befd948..7fd35516dc 100644
--- a/docs/sample_config.yaml
+++ b/docs/sample_config.yaml
@@ -825,6 +825,8 @@ log_config: "CONFDIR/SERVERNAME.log.config"
# "remote" for when users are trying to join rooms not on the server (which
# can be more expensive)
# - one for ratelimiting how often a user or IP can attempt to validate a 3PID.
+# - two for ratelimiting how often invites can be sent in a room or to a
+# specific user.
#
# The defaults are as shown below.
#
@@ -862,6 +864,14 @@ log_config: "CONFDIR/SERVERNAME.log.config"
#rc_3pid_validation:
# per_second: 0.003
# burst_count: 5
+#
+#rc_invites:
+# per_room:
+# per_second: 0.3
+# burst_count: 10
+# per_user:
+# per_second: 0.003
+# burst_count: 5
# Ratelimiting settings for incoming federation
#
diff --git a/synapse/config/ratelimiting.py b/synapse/config/ratelimiting.py
index 76f382527d..def33a60ad 100644
--- a/synapse/config/ratelimiting.py
+++ b/synapse/config/ratelimiting.py
@@ -107,6 +107,15 @@ class RatelimitConfig(Config):
defaults={"per_second": 0.003, "burst_count": 5},
)
+ self.rc_invites_per_room = RateLimitConfig(
+ config.get("rc_invites", {}).get("per_room", {}),
+ defaults={"per_second": 0.3, "burst_count": 10},
+ )
+ self.rc_invites_per_user = RateLimitConfig(
+ config.get("rc_invites", {}).get("per_user", {}),
+ defaults={"per_second": 0.003, "burst_count": 5},
+ )
+
def generate_config_section(self, **kwargs):
return """\
## Ratelimiting ##
@@ -137,6 +146,8 @@ class RatelimitConfig(Config):
# "remote" for when users are trying to join rooms not on the server (which
# can be more expensive)
# - one for ratelimiting how often a user or IP can attempt to validate a 3PID.
+ # - two for ratelimiting how often invites can be sent in a room or to a
+ # specific user.
#
# The defaults are as shown below.
#
@@ -174,6 +185,14 @@ class RatelimitConfig(Config):
#rc_3pid_validation:
# per_second: 0.003
# burst_count: 5
+ #
+ #rc_invites:
+ # per_room:
+ # per_second: 0.3
+ # burst_count: 10
+ # per_user:
+ # per_second: 0.003
+ # burst_count: 5
# Ratelimiting settings for incoming federation
#
diff --git a/synapse/federation/federation_client.py b/synapse/federation/federation_client.py
index d330ae5dbc..40e1451201 100644
--- a/synapse/federation/federation_client.py
+++ b/synapse/federation/federation_client.py
@@ -810,7 +810,7 @@ class FederationClient(FederationBase):
"User's homeserver does not support this room version",
Codes.UNSUPPORTED_ROOM_VERSION,
)
- elif e.code == 403:
+ elif e.code in (403, 429):
raise e.to_synapse_error()
else:
raise
diff --git a/synapse/handlers/federation.py b/synapse/handlers/federation.py
index b6dc7f99b6..dbdfd56ff5 100644
--- a/synapse/handlers/federation.py
+++ b/synapse/handlers/federation.py
@@ -1617,6 +1617,10 @@ class FederationHandler(BaseHandler):
if event.state_key == self._server_notices_mxid:
raise SynapseError(HTTPStatus.FORBIDDEN, "Cannot invite this user")
+ # We retrieve the room member handler here as to not cause a cyclic dependency
+ member_handler = self.hs.get_room_member_handler()
+ member_handler.ratelimit_invite(event.room_id, event.state_key)
+
# keep a record of the room version, if we don't yet know it.
# (this may get overwritten if we later get a different room version in a
# join dance).
diff --git a/synapse/handlers/room.py b/synapse/handlers/room.py
index ee27d99135..07b2187eb1 100644
--- a/synapse/handlers/room.py
+++ b/synapse/handlers/room.py
@@ -126,6 +126,10 @@ class RoomCreationHandler(BaseHandler):
self.third_party_event_rules = hs.get_third_party_event_rules()
+ self._invite_burst_count = (
+ hs.config.ratelimiting.rc_invites_per_room.burst_count
+ )
+
async def upgrade_room(
self, requester: Requester, old_room_id: str, new_version: RoomVersion
) -> str:
@@ -662,6 +666,9 @@ class RoomCreationHandler(BaseHandler):
invite_3pid_list = []
invite_list = []
+ if len(invite_list) + len(invite_3pid_list) > self._invite_burst_count:
+ raise SynapseError(400, "Cannot invite so many users at once")
+
await self.event_creation_handler.assert_accepted_privacy_policy(requester)
power_level_content_override = config.get("power_level_content_override")
diff --git a/synapse/handlers/room_member.py b/synapse/handlers/room_member.py
index e001e418f9..d335da6f19 100644
--- a/synapse/handlers/room_member.py
+++ b/synapse/handlers/room_member.py
@@ -85,6 +85,17 @@ class RoomMemberHandler(metaclass=abc.ABCMeta):
burst_count=hs.config.ratelimiting.rc_joins_remote.burst_count,
)
+ self._invites_per_room_limiter = Ratelimiter(
+ clock=self.clock,
+ rate_hz=hs.config.ratelimiting.rc_invites_per_room.per_second,
+ burst_count=hs.config.ratelimiting.rc_invites_per_room.burst_count,
+ )
+ self._invites_per_user_limiter = Ratelimiter(
+ clock=self.clock,
+ rate_hz=hs.config.ratelimiting.rc_invites_per_user.per_second,
+ burst_count=hs.config.ratelimiting.rc_invites_per_user.burst_count,
+ )
+
# This is only used to get at ratelimit function, and
# maybe_kick_guest_users. It's fine there are multiple of these as
# it doesn't store state.
@@ -144,6 +155,12 @@ class RoomMemberHandler(metaclass=abc.ABCMeta):
"""
raise NotImplementedError()
+ def ratelimit_invite(self, room_id: str, invitee_user_id: str):
+ """Ratelimit invites by room and by target user.
+ """
+ self._invites_per_room_limiter.ratelimit(room_id)
+ self._invites_per_user_limiter.ratelimit(invitee_user_id)
+
async def _local_membership_update(
self,
requester: Requester,
@@ -387,8 +404,12 @@ class RoomMemberHandler(metaclass=abc.ABCMeta):
raise SynapseError(403, "This room has been blocked on this server")
if effective_membership_state == Membership.INVITE:
+ target_id = target.to_string()
+ if ratelimit:
+ self.ratelimit_invite(room_id, target_id)
+
# block any attempts to invite the server notices mxid
- if target.to_string() == self._server_notices_mxid:
+ if target_id == self._server_notices_mxid:
raise SynapseError(HTTPStatus.FORBIDDEN, "Cannot invite this user")
block_invite = False
@@ -412,7 +433,7 @@ class RoomMemberHandler(metaclass=abc.ABCMeta):
block_invite = True
if not await self.spam_checker.user_may_invite(
- requester.user.to_string(), target.to_string(), room_id
+ requester.user.to_string(), target_id, room_id
):
logger.info("Blocking invite due to spam checker")
block_invite = True
diff --git a/tests/handlers/test_federation.py b/tests/handlers/test_federation.py
index 0b24b89a2e..74503112f5 100644
--- a/tests/handlers/test_federation.py
+++ b/tests/handlers/test_federation.py
@@ -16,7 +16,7 @@ import logging
from unittest import TestCase
from synapse.api.constants import EventTypes
-from synapse.api.errors import AuthError, Codes, SynapseError
+from synapse.api.errors import AuthError, Codes, LimitExceededError, SynapseError
from synapse.api.room_versions import RoomVersions
from synapse.events import EventBase
from synapse.federation.federation_base import event_from_pdu_json
@@ -191,6 +191,97 @@ class FederationTestCase(unittest.HomeserverTestCase):
self.assertEqual(sg, sg2)
+ @unittest.override_config(
+ {"rc_invites": {"per_room": {"per_second": 0.5, "burst_count": 3}}}
+ )
+ def test_invite_by_room_ratelimit(self):
+ """Tests that invites from federation in a room are actually rate-limited.
+ """
+ other_server = "otherserver"
+ other_user = "@otheruser:" + other_server
+
+ # create the room
+ user_id = self.register_user("kermit", "test")
+ tok = self.login("kermit", "test")
+ room_id = self.helper.create_room_as(room_creator=user_id, tok=tok)
+ room_version = self.get_success(self.store.get_room_version(room_id))
+
+ def create_invite_for(local_user):
+ return event_from_pdu_json(
+ {
+ "type": EventTypes.Member,
+ "content": {"membership": "invite"},
+ "room_id": room_id,
+ "sender": other_user,
+ "state_key": local_user,
+ "depth": 32,
+ "prev_events": [],
+ "auth_events": [],
+ "origin_server_ts": self.clock.time_msec(),
+ },
+ room_version,
+ )
+
+ for i in range(3):
+ self.get_success(
+ self.handler.on_invite_request(
+ other_server,
+ create_invite_for("@user-%d:test" % (i,)),
+ room_version,
+ )
+ )
+
+ self.get_failure(
+ self.handler.on_invite_request(
+ other_server, create_invite_for("@user-4:test"), room_version,
+ ),
+ exc=LimitExceededError,
+ )
+
+ @unittest.override_config(
+ {"rc_invites": {"per_user": {"per_second": 0.5, "burst_count": 3}}}
+ )
+ def test_invite_by_user_ratelimit(self):
+ """Tests that invites from federation to a particular user are
+ actually rate-limited.
+ """
+ other_server = "otherserver"
+ other_user = "@otheruser:" + other_server
+
+ # create the room
+ user_id = self.register_user("kermit", "test")
+ tok = self.login("kermit", "test")
+
+ def create_invite():
+ room_id = self.helper.create_room_as(room_creator=user_id, tok=tok)
+ room_version = self.get_success(self.store.get_room_version(room_id))
+ return event_from_pdu_json(
+ {
+ "type": EventTypes.Member,
+ "content": {"membership": "invite"},
+ "room_id": room_id,
+ "sender": other_user,
+ "state_key": "@user:test",
+ "depth": 32,
+ "prev_events": [],
+ "auth_events": [],
+ "origin_server_ts": self.clock.time_msec(),
+ },
+ room_version,
+ )
+
+ for i in range(3):
+ event = create_invite()
+ self.get_success(
+ self.handler.on_invite_request(other_server, event, event.room_version,)
+ )
+
+ event = create_invite()
+ self.get_failure(
+ self.handler.on_invite_request(other_server, event, event.room_version,),
+ exc=LimitExceededError,
+ )
+
def _build_and_send_join_event(self, other_server, other_user, room_id):
join_event = self.get_success(
self.handler.on_make_join_request(other_server, room_id, other_user)
diff --git a/tests/rest/client/v1/test_rooms.py b/tests/rest/client/v1/test_rooms.py
index d4e3165436..2548b3a80c 100644
--- a/tests/rest/client/v1/test_rooms.py
+++ b/tests/rest/client/v1/test_rooms.py
@@ -616,6 +616,41 @@ class RoomMemberStateTestCase(RoomBase):
self.assertEquals(json.loads(content), channel.json_body)
+class RoomInviteRatelimitTestCase(RoomBase):
+ user_id = "@sid1:red"
+
+ servlets = [
+ admin.register_servlets,
+ profile.register_servlets,
+ room.register_servlets,
+ ]
+
+ @unittest.override_config(
+ {"rc_invites": {"per_room": {"per_second": 0.5, "burst_count": 3}}}
+ )
+ def test_invites_by_rooms_ratelimit(self):
+ """Tests that invites in a room are actually rate-limited."""
+ room_id = self.helper.create_room_as(self.user_id)
+
+ for i in range(3):
+ self.helper.invite(room_id, self.user_id, "@user-%s:red" % (i,))
+
+ self.helper.invite(room_id, self.user_id, "@user-4:red", expect_code=429)
+
+ @unittest.override_config(
+ {"rc_invites": {"per_user": {"per_second": 0.5, "burst_count": 3}}}
+ )
+ def test_invites_by_users_ratelimit(self):
+ """Tests that invites to a specific user are actually rate-limited."""
+
+ for i in range(3):
+ room_id = self.helper.create_room_as(self.user_id)
+ self.helper.invite(room_id, self.user_id, "@other-users:red")
+
+ room_id = self.helper.create_room_as(self.user_id)
+ self.helper.invite(room_id, self.user_id, "@other-users:red", expect_code=429)
+
+
class RoomJoinRatelimitTestCase(RoomBase):
user_id = "@sid1:red"
|
