add options to require an access_token to GET /profile and /publicRooms on CS API (#5083)

This commit adds two config options:

* `restrict_public_rooms_to_local_users`

Requires auth to fetch the public rooms directory through the CS API and disables fetching it through the federation API.

* `require_auth_for_profile_requests`

When set to `true`, requires that requests to `/profile` over the CS API are authenticated, and only returns the user's profile if the requester shares a room with the profile's owner, as per MSC1301.

MSC1301 also specifies a behaviour for federation (only returning the profile if the server asking for it shares a room with the profile's owner), but that's currently really non-trivial to do in a not too expensive way. Next step is writing down a MSC that allows a HS to specify which user sent the profile query. In this implementation, Synapse won't send a profile query over federation if it doesn't believe it already shares a room with the profile's owner, though.

Groups have been intentionally omitted from this commit.

1 files changed, 14 insertions, 0 deletions

diff --git a/docs/sample_config.yaml b/docs/sample_config.yaml

index b6b9da6e41..bdfc34c6bd 100644
--- a/docs/sample_config.yaml
+++ b/docs/sample_config.yaml
@@ -69,6 +69,20 @@ pid_file: DATADIR/homeserver.pid
 #
 #use_presence: false
 
+# Whether to require authentication to retrieve profile data (avatars,
+# display names) of other users through the client API. Defaults to
+# 'false'. Note that profile data is also available via the federation
+# API, so this setting is of limited value if federation is enabled on
+# the server.
+#
+#require_auth_for_profile_requests: true
+
+# If set to 'true', requires authentication to access the server's
+# public rooms directory through the client API, and forbids any other
+# homeserver to fetch it via federation. Defaults to 'false'.
+#
+#restrict_public_rooms_to_local_users: true
+
 # The GC threshold parameters to pass to `gc.set_threshold`, if defined
 #
 #gc_thresholds: [700, 10, 10]