privacy by default for room dir

UPGRADE.rst

@@ -75,6 +75,23 @@ for example:
      wget https://packages.matrix.org/debian/pool/main/m/matrix-synapse-py3/matrix-synapse-py3_1.3.0+stretch1_amd64.deb
      dpkg -i matrix-synapse-py3_1.3.0+stretch1_amd64.deb
 
+Upgrading to v1.5.2
+===================
+
+In an attempt to configure Synapse in a privacy preserving way, the default
+behaviours of ``allow_public_rooms_without_auth`` and
+``allow_public_rooms_over_federation`` have been inverted. This means that by
+default, only authenticated users querying the Client/Server API will be able
+to query the room directory, and relatedly that the server will not share
+room directory information with other servers over federation.
+
+If your installation does not explicitly set these settings one way or the other
+and you want either setting to be ``true`` then it will necessary to update
+``homeserver.yaml`` accordingly.
+
+For more details on the surrounding context see our `explainer
+<https://matrix.org/blog/2019/11/09/avoiding-unwelcome-visitors-on-private-matrix-servers>`_.
+
 
 Upgrading to v1.5.0
 ===================

changelog.d/6354.feature

@@ -0,0 +1 @@
+Configure privacy preserving settings by default for the room directory.

docs/sample_config.yaml

@@ -54,15 +54,16 @@ pid_file: DATADIR/homeserver.pid
 #
 #require_auth_for_profile_requests: true
 
-# If set to 'false', requires authentication to access the server's public rooms
-# directory through the client API. Defaults to 'true'.
+# If set to 'true', removes the need for authentication to access the server's
+# public rooms directory through the client API, meaning that anyone can
+# query the room directory. Defaults to 'false'.
 #
-#allow_public_rooms_without_auth: false
+#allow_public_rooms_without_auth: true
 
-# If set to 'false', forbids any other homeserver to fetch the server's public
-# rooms directory via federation. Defaults to 'true'.
+# If set to 'true', allows any other homeserver to fetch the server's public
+# rooms directory via federation. Defaults to 'false'.
 #
-#allow_public_rooms_over_federation: false
+#allow_public_rooms_over_federation: true
 
 # The default room version for newly created rooms.
 #

synapse/config/server.py

@@ -118,15 +118,16 @@ def read_config(self, config, **kwargs):
             self.allow_public_rooms_without_auth = False
             self.allow_public_rooms_over_federation = False
         else:
-            # If set to 'False', requires authentication to access the server's public
-            # rooms directory through the client API. Defaults to 'True'.
+            # If set to 'true', removes the need for authentication to access the server's
+            # public rooms directory through the client API, meaning that anyone can
+            # query the room directory. Defaults to 'false'.
             self.allow_public_rooms_without_auth = config.get(
-                "allow_public_rooms_without_auth", True
+                "allow_public_rooms_without_auth", False
             )
-            # If set to 'False', forbids any other homeserver to fetch the server's public
-            # rooms directory via federation. Defaults to 'True'.
+            # If set to 'true', allows any other homeserver to fetch the server's public
+            # rooms directory via federation. Defaults to 'false'.
             self.allow_public_rooms_over_federation = config.get(
-                "allow_public_rooms_over_federation", True
+                "allow_public_rooms_over_federation", False
             )
 
         default_room_version = config.get("default_room_version", DEFAULT_ROOM_VERSION)
@@ -500,15 +501,16 @@ def generate_config_section(
         #
         #require_auth_for_profile_requests: true
 
-        # If set to 'false', requires authentication to access the server's public rooms
-        # directory through the client API. Defaults to 'true'.
+        # If set to 'true', removes the need for authentication to access the server's
+        # public rooms directory through the client API, meaning that anyone can
+        # query the room directory. Defaults to 'false'.
         #
-        #allow_public_rooms_without_auth: false
+        #allow_public_rooms_without_auth: true
 
-        # If set to 'false', forbids any other homeserver to fetch the server's public
-        # rooms directory via federation. Defaults to 'true'.
+        # If set to 'true', allows any other homeserver to fetch the server's public
+        # rooms directory via federation. Defaults to 'false'.
         #
-        #allow_public_rooms_over_federation: false
+        #allow_public_rooms_over_federation: true
 
         # The default room version for newly created rooms.
         #