Default PL100 to enable encryption in a room

changelog.d/7230.feature

@@ -0,0 +1 @@
+Change defaults to require power level 100 for enabling encryption in a room.

synapse/handlers/room.py

@@ -806,6 +806,7 @@ def send(etype, content, **kwargs):
                     EventTypes.RoomAvatar: 50,
                     EventTypes.Tombstone: 100,
                     EventTypes.ServerACL: 100,
+                    EventTypes.RoomEncryption: 100,
                 },
                 "events_default": 0,
                 "state_default": 50,

tests/rest/client/test_power_levels.py

@@ -0,0 +1,163 @@
+# -*- coding: utf-8 -*-
+# Copyright 2020 The Matrix.org Foundation C.I.C.
+#
+# 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.
+
+from synapse.rest import admin
+from synapse.rest.client.v1 import login, room
+from synapse.rest.client.v2_alpha import sync
+
+from tests.unittest import HomeserverTestCase
+
+
+class PowerLevelsTestCase(HomeserverTestCase):
+    """Tests that power levels are enforced in various situations"""
+
+    servlets = [
+        admin.register_servlets,
+        room.register_servlets,
+        login.register_servlets,
+        sync.register_servlets,
+    ]
+
+    def make_homeserver(self, reactor, clock):
+        config = self.default_config()
+
+        return self.setup_test_homeserver(config=config)
+
+    def prepare(self, reactor, clock, hs):
+        # register a room admin, moderator and regular user
+        self.admin_user_id = self.register_user("admin", "pass")
+        self.admin_access_token = self.login("admin", "pass")
+        self.mod_user_id = self.register_user("mod", "pass")
+        self.mod_access_token = self.login("mod", "pass")
+        self.user_user_id = self.register_user("user", "pass")
+        self.user_access_token = self.login("user", "pass")
+
+        # Create a room
+        self.room_id = self.helper.create_room_as(
+            self.admin_user_id, tok=self.admin_access_token
+        )
+
+        # Invite the other users
+        self.helper.invite(
+            room=self.room_id,
+            src=self.admin_user_id,
+            tok=self.admin_access_token,
+            targ=self.mod_user_id,
+        )
+        self.helper.invite(
+            room=self.room_id,
+            src=self.admin_user_id,
+            tok=self.admin_access_token,
+            targ=self.user_user_id,
+        )
+
+        # Make the other users join the room
+        self.helper.join(
+            room=self.room_id, user=self.mod_user_id, tok=self.mod_access_token
+        )
+        self.helper.join(
+            room=self.room_id, user=self.user_user_id, tok=self.user_access_token
+        )
+
+        # Mod the mod
+        room_power_levels = self.helper.get_state(
+            self.room_id, "m.room.power_levels", tok=self.admin_access_token,
+        )
+
+        # Update existing power levels with mod at PL50
+        room_power_levels["users"].update({self.mod_user_id: 50})
+
+        self.helper.send_state(
+            self.room_id,
+            "m.room.power_levels",
+            room_power_levels,
+            tok=self.admin_access_token,
+        )
+
+    def test_non_admins_cannot_enable_room_encryption(self):
+        # have the mod try to enable room encryption
+        self.helper.send_state(
+            self.room_id,
+            "m.room.encryption",
+            {"algorithm": "m.megolm.v1.aes-sha2"},
+            tok=self.mod_access_token,
+            expect_code=403,  # expect failure
+        )
+
+        # have the user try to enable room encryption
+        self.helper.send_state(
+            self.room_id,
+            "m.room.encryption",
+            {"algorithm": "m.megolm.v1.aes-sha2"},
+            tok=self.user_access_token,
+            expect_code=403,  # expect failure
+        )
+
+    def test_non_admins_cannot_send_server_acl(self):
+        # have the mod try to send a server ACL
+        self.helper.send_state(
+            self.room_id,
+            "m.room.server_acl",
+            {
+                "allow": ["*"],
+                "allow_ip_literals": False,
+                "deny": ["*.evil.com", "evil.com"],
+            },
+            tok=self.mod_access_token,
+            expect_code=403,  # expect failure
+        )
+
+        # have the user try to send a server ACL
+        self.helper.send_state(
+            self.room_id,
+            "m.room.server_acl",
+            {
+                "allow": ["*"],
+                "allow_ip_literals": False,
+                "deny": ["*.evil.com", "evil.com"],
+            },
+            tok=self.user_access_token,
+            expect_code=403,  # expect failure
+        )
+
+    def test_non_admins_cannot_tombstone_room(self):
+        # Create another room that will serve as our "upgraded room"
+        self.upgraded_room_id = self.helper.create_room_as(
+            self.admin_user_id, tok=self.admin_access_token
+        )
+
+        # have the mod try to send a tombstone event
+        self.helper.send_state(
+            self.room_id,
+            "m.room.tombstone",
+            {
+                "body": "This room has been replaced",
+                "replacement_room": self.upgraded_room_id,
+            },
+            tok=self.mod_access_token,
+            expect_code=403,  # expect failure
+        )
+
+        # have the user try to send a tombstone event
+        self.helper.send_state(
+            self.room_id,
+            "m.room.tombstone",
+            {
+                "body": "This room has been replaced",
+                "replacement_room": self.upgraded_room_id,
+            },
+            tok=self.user_access_token,
+            expect_code=403,  # expect failure
+        )

tests/rest/client/v1/utils.py

@@ -142,7 +142,16 @@ def send_event(
 
         return channel.json_body
 
-    def send_state(self, room_id, event_type, body, tok, expect_code=200, state_key=""):
+    def _read_write_state(
+        self,
+        room_id,
+        event_type,
+        body,
+        tok,
+        expect_code=200,
+        state_key="",
+        method="GET",
+    ):
         path = "/_matrix/client/r0/rooms/%s/state/%s/%s" % (
             room_id,
             event_type,
@@ -152,8 +161,12 @@ def send_state(self, room_id, event_type, body, tok, expect_code=200, state_key=
             path = path + "?access_token=%s" % tok
 
         request, channel = make_request(
-            self.hs.get_reactor(), "PUT", path, json.dumps(body).encode("utf8")
+            self.hs.get_reactor(),
+            method,
+            path,
+            content=json.dumps(body).encode("utf8") if body else b""
         )
+
         render(request, self.resource, self.hs.get_reactor())
 
         assert int(channel.result["code"]) == expect_code, (
@@ -163,6 +176,16 @@ def send_state(self, room_id, event_type, body, tok, expect_code=200, state_key=
 
         return channel.json_body
 
+    def get_state(self, room_id, event_type, tok, expect_code=200, state_key=""):
+        return self._read_write_state(
+            room_id, event_type, None, tok, expect_code, state_key, method="GET"
+        )
+
+    def send_state(self, room_id, event_type, body, tok, expect_code=200, state_key=""):
+        return self._read_write_state(
+            room_id, event_type, body, tok, expect_code, state_key, method="PUT"
+        )
+
     def upload_media(
         self,
         resource: Resource,