From 5ed109d59f46c5185395f7c76050274fdd6abc15 Mon Sep 17 00:00:00 2001
From: Richard van der Hoff <github@rvanderhoff.org.uk>
Date: Tue, 19 Sep 2017 12:20:11 +0100
Subject: PoC for filtering spammy events (#2456)

Demonstration of how you might add some hooks to filter out spammy events.
---
 synapse/handlers/message.py | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

(limited to 'synapse/handlers')

diff --git a/synapse/handlers/message.py b/synapse/handlers/message.py
index be4f123c54..da18bf23db 100644
--- a/synapse/handlers/message.py
+++ b/synapse/handlers/message.py
@@ -12,7 +12,7 @@
 # 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.events import spamcheck
 from twisted.internet import defer
 
 from synapse.api.constants import EventTypes, Membership
@@ -321,6 +321,12 @@ class MessageHandler(BaseHandler):
             token_id=requester.access_token_id,
             txn_id=txn_id
         )
+
+        if spamcheck.check_event_for_spam(event):
+            raise SynapseError(
+                403, "Spam is not permitted here", Codes.FORBIDDEN
+            )
+
         yield self.send_nonmember_event(
             requester,
             event,
-- 
cgit 1.5.1


From 2eabdf3f9860c78598d026574807da463bf40f2e Mon Sep 17 00:00:00 2001
From: Richard van der Hoff <richard@matrix.org>
Date: Tue, 19 Sep 2017 12:18:01 +0100
Subject: add some comments to on_exchange_third_party_invite_request

---
 synapse/handlers/federation.py | 11 +++++++++++
 1 file changed, 11 insertions(+)

(limited to 'synapse/handlers')

diff --git a/synapse/handlers/federation.py b/synapse/handlers/federation.py
index 4669199b2d..2637f41dcd 100644
--- a/synapse/handlers/federation.py
+++ b/synapse/handlers/federation.py
@@ -2090,6 +2090,14 @@ class FederationHandler(BaseHandler):
     @defer.inlineCallbacks
     @log_function
     def on_exchange_third_party_invite_request(self, origin, room_id, event_dict):
+        """Handle an exchange_third_party_invite request from a remote server
+
+        The remote server will call this when it wants to turn a 3pid invite
+        into a normal m.room.member invite.
+
+        Returns:
+            Deferred: resolves (to None)
+        """
         builder = self.event_builder_factory.new(event_dict)
 
         message_handler = self.hs.get_handlers().message_handler
@@ -2108,9 +2116,12 @@ class FederationHandler(BaseHandler):
             raise e
         yield self._check_signature(event, context)
 
+        # XXX we send the invite here, but send_membership_event also sends it,
+        # so we end up making two requests. I think this is redundant.
         returned_invite = yield self.send_invite(origin, event)
         # TODO: Make sure the signatures actually are correct.
         event.signatures.update(returned_invite.signatures)
+
         member_handler = self.hs.get_handlers().room_member_handler
         yield member_handler.send_membership_event(None, event, context)
 
-- 
cgit 1.5.1


From aa620d09a01c226d7a6fbc0d839d8abd347a2b2e Mon Sep 17 00:00:00 2001
From: Richard van der Hoff <github@rvanderhoff.org.uk>
Date: Tue, 19 Sep 2017 16:08:14 +0100
Subject: Add a config option to block all room invites (#2457)

- allows sysadmins the ability to lock down their servers so that people can't
send their users room invites.
---
 synapse/api/auth.py             |  8 ++++++++
 synapse/config/server.py        | 10 ++++++++++
 synapse/handlers/federation.py  |  3 +++
 synapse/handlers/room_member.py | 22 ++++++++++++++++++++++
 tests/utils.py                  |  1 +
 5 files changed, 44 insertions(+)

(limited to 'synapse/handlers')

diff --git a/synapse/api/auth.py b/synapse/api/auth.py
index e3da45b416..72858cca1f 100644
--- a/synapse/api/auth.py
+++ b/synapse/api/auth.py
@@ -519,6 +519,14 @@ class Auth(object):
             )
 
     def is_server_admin(self, user):
+        """ Check if the given user is a local server admin.
+
+        Args:
+            user (str): mxid of user to check
+
+        Returns:
+            bool: True if the user is an admin
+        """
         return self.store.is_server_admin(user)
 
     @defer.inlineCallbacks
diff --git a/synapse/config/server.py b/synapse/config/server.py
index 89d61a0503..c9a1715f1f 100644
--- a/synapse/config/server.py
+++ b/synapse/config/server.py
@@ -43,6 +43,12 @@ class ServerConfig(Config):
 
         self.filter_timeline_limit = config.get("filter_timeline_limit", -1)
 
+        # Whether we should block invites sent to users on this server
+        # (other than those sent by local server admins)
+        self.block_non_admin_invites = config.get(
+            "block_non_admin_invites", False,
+        )
+
         if self.public_baseurl is not None:
             if self.public_baseurl[-1] != '/':
                 self.public_baseurl += '/'
@@ -194,6 +200,10 @@ class ServerConfig(Config):
         # and sync operations. The default value is -1, means no upper limit.
         # filter_timeline_limit: 5000
 
+        # Whether room invites to users on this server should be blocked
+        # (except those sent by local server admins). The default is False.
+        # block_non_admin_invites: True
+
         # List of ports that Synapse should listen on, their purpose and their
         # configuration.
         listeners:
diff --git a/synapse/handlers/federation.py b/synapse/handlers/federation.py
index 2637f41dcd..18f87cad67 100644
--- a/synapse/handlers/federation.py
+++ b/synapse/handlers/federation.py
@@ -1074,6 +1074,9 @@ class FederationHandler(BaseHandler):
         if is_blocked:
             raise SynapseError(403, "This room has been blocked on this server")
 
+        if self.hs.config.block_non_admin_invites:
+            raise SynapseError(403, "This server does not accept room invites")
+
         membership = event.content.get("membership")
         if event.type != EventTypes.Member or membership != Membership.INVITE:
             raise SynapseError(400, "The event was not an m.room.member invite event")
diff --git a/synapse/handlers/room_member.py b/synapse/handlers/room_member.py
index b3f979b246..9a498c2d3e 100644
--- a/synapse/handlers/room_member.py
+++ b/synapse/handlers/room_member.py
@@ -191,6 +191,8 @@ class RoomMemberHandler(BaseHandler):
         if action in ["kick", "unban"]:
             effective_membership_state = "leave"
 
+        # if this is a join with a 3pid signature, we may need to turn a 3pid
+        # invite into a normal invite before we can handle the join.
         if third_party_signed is not None:
             replication = self.hs.get_replication_layer()
             yield replication.exchange_third_party_invite(
@@ -208,6 +210,16 @@ class RoomMemberHandler(BaseHandler):
             if is_blocked:
                 raise SynapseError(403, "This room has been blocked on this server")
 
+        if (effective_membership_state == "invite" and
+                self.hs.config.block_non_admin_invites):
+            is_requester_admin = yield self.auth.is_server_admin(
+                requester.user,
+            )
+            if not is_requester_admin:
+                raise SynapseError(
+                    403, "Invites have been disabled on this server",
+                )
+
         latest_event_ids = yield self.store.get_latest_event_ids_in_room(room_id)
         current_state_ids = yield self.state_handler.get_current_state_ids(
             room_id, latest_event_ids=latest_event_ids,
@@ -471,6 +483,16 @@ class RoomMemberHandler(BaseHandler):
             requester,
             txn_id
     ):
+        if self.hs.config.block_non_admin_invites:
+            is_requester_admin = yield self.auth.is_server_admin(
+                requester.user,
+            )
+            if not is_requester_admin:
+                raise SynapseError(
+                    403, "Invites have been disabled on this server",
+                    Codes.FORBIDDEN,
+                )
+
         invitee = yield self._lookup_3pid(
             id_server, medium, address
         )
diff --git a/tests/utils.py b/tests/utils.py
index 4f7e32b3ab..3c81a3e16d 100644
--- a/tests/utils.py
+++ b/tests/utils.py
@@ -56,6 +56,7 @@ def setup_test_homeserver(name="test", datastore=None, config=None, **kargs):
         config.worker_replication_url = ""
         config.worker_app = None
         config.email_enable_notifs = False
+        config.block_non_admin_invites = False
 
     config.use_frozen_dicts = True
     config.database_config = {"name": "sqlite3"}
-- 
cgit 1.5.1


From 3166ed55b23d0939f08337336439d9222117c9e6 Mon Sep 17 00:00:00 2001
From: Erik Johnston <erikj@jki.re>
Date: Fri, 22 Sep 2017 14:44:17 +0100
Subject: Fix device list when rejoining room (#2461)

---
 synapse/handlers/sync.py | 16 ++++++++++++++--
 1 file changed, 14 insertions(+), 2 deletions(-)

(limited to 'synapse/handlers')

diff --git a/synapse/handlers/sync.py b/synapse/handlers/sync.py
index bb78c25ee5..af1b527840 100644
--- a/synapse/handlers/sync.py
+++ b/synapse/handlers/sync.py
@@ -980,7 +980,18 @@ class SyncHandler(object):
             # We want to figure out if we joined the room at some point since
             # the last sync (even if we have since left). This is to make sure
             # we do send down the room, and with full state, where necessary
+
             old_state_ids = None
+            if room_id in joined_room_ids and non_joins:
+                # Always include if the user (re)joined the room, especially
+                # important so that device list changes are calculated correctly.
+                # If there are non join member events, but we are still in the room,
+                # then the user must have left and joined
+                newly_joined_rooms.append(room_id)
+
+                # User is in the room so we don't need to do the invite/leave checks
+                continue
+
             if room_id in joined_room_ids or has_join:
                 old_state_ids = yield self.get_state_at(room_id, since_token)
                 old_mem_ev_id = old_state_ids.get((EventTypes.Member, user_id), None)
@@ -992,8 +1003,9 @@ class SyncHandler(object):
                 if not old_mem_ev or old_mem_ev.membership != Membership.JOIN:
                     newly_joined_rooms.append(room_id)
 
-                if room_id in joined_room_ids:
-                    continue
+            # If user is in the room then we don't need to do the invite/leave checks
+            if room_id in joined_room_ids:
+                continue
 
             if not non_joins:
                 continue
-- 
cgit 1.5.1


From e3edca3b5d23e52d4b51afe5fa9fe2da79f09700 Mon Sep 17 00:00:00 2001
From: Erik Johnston <erik@matrix.org>
Date: Mon, 25 Sep 2017 17:35:39 +0100
Subject: Refactor to speed up incremental syncs

---
 synapse/handlers/sync.py | 23 ++++++++++++++++++-----
 1 file changed, 18 insertions(+), 5 deletions(-)

(limited to 'synapse/handlers')

diff --git a/synapse/handlers/sync.py b/synapse/handlers/sync.py
index af1b527840..dd0ec00ae6 100644
--- a/synapse/handlers/sync.py
+++ b/synapse/handlers/sync.py
@@ -293,11 +293,6 @@ class SyncHandler(object):
             timeline_limit = sync_config.filter_collection.timeline_limit()
             block_all_timeline = sync_config.filter_collection.blocks_all_room_timeline()
 
-            # Pull out the current state, as we always want to include those events
-            # in the timeline if they're there.
-            current_state_ids = yield self.state.get_current_state_ids(room_id)
-            current_state_ids = frozenset(current_state_ids.itervalues())
-
             if recents is None or newly_joined_room or timeline_limit < len(recents):
                 limited = True
             else:
@@ -305,6 +300,15 @@ class SyncHandler(object):
 
             if recents:
                 recents = sync_config.filter_collection.filter_room_timeline(recents)
+
+                # We check if there are any state events, if there are then we pass
+                # all current state events to the filter_events function. This is to
+                # ensure that we always include current state in the timeline
+                current_state_ids = frozenset()
+                if any(e.is_state() for e in recents):
+                    current_state_ids = yield self.state.get_current_state_ids(room_id)
+                    current_state_ids = frozenset(current_state_ids.itervalues())
+
                 recents = yield filter_events_for_client(
                     self.store,
                     sync_config.user.to_string(),
@@ -341,6 +345,15 @@ class SyncHandler(object):
                 loaded_recents = sync_config.filter_collection.filter_room_timeline(
                     events
                 )
+
+                # We check if there are any state events, if there are then we pass
+                # all current state events to the filter_events function. This is to
+                # ensure that we always include current state in the timeline
+                current_state_ids = frozenset()
+                if any(e.is_state() for e in loaded_recents):
+                    current_state_ids = yield self.state.get_current_state_ids(room_id)
+                    current_state_ids = frozenset(current_state_ids.itervalues())
+
                 loaded_recents = yield filter_events_for_client(
                     self.store,
                     sync_config.user.to_string(),
-- 
cgit 1.5.1


From 6cd5fcd5366cfef4959d107e818d0e20d78aa483 Mon Sep 17 00:00:00 2001
From: David Baker <dave@matrix.org>
Date: Tue, 26 Sep 2017 19:20:23 +0100
Subject: Make the spam checker a module

---
 synapse/config/homeserver.py          |  4 +++-
 synapse/events/spamcheck.py           | 37 +++++++++++++++++++----------------
 synapse/federation/federation_base.py |  5 ++---
 synapse/handlers/message.py           |  5 +++--
 synapse/server.py                     |  5 +++++
 5 files changed, 33 insertions(+), 23 deletions(-)

(limited to 'synapse/handlers')

diff --git a/synapse/config/homeserver.py b/synapse/config/homeserver.py
index b22cacf8dc..3f9d9d5f8b 100644
--- a/synapse/config/homeserver.py
+++ b/synapse/config/homeserver.py
@@ -34,6 +34,7 @@ from .password_auth_providers import PasswordAuthProviderConfig
 from .emailconfig import EmailConfig
 from .workers import WorkerConfig
 from .push import PushConfig
+from .spam_checker import SpamCheckerConfig
 
 
 class HomeServerConfig(TlsConfig, ServerConfig, DatabaseConfig, LoggingConfig,
@@ -41,7 +42,8 @@ class HomeServerConfig(TlsConfig, ServerConfig, DatabaseConfig, LoggingConfig,
                        VoipConfig, RegistrationConfig, MetricsConfig, ApiConfig,
                        AppServiceConfig, KeyConfig, SAML2Config, CasConfig,
                        JWTConfig, PasswordConfig, EmailConfig,
-                       WorkerConfig, PasswordAuthProviderConfig, PushConfig,):
+                       WorkerConfig, PasswordAuthProviderConfig, PushConfig,
+                       SpamCheckerConfig,):
     pass
 
 
diff --git a/synapse/events/spamcheck.py b/synapse/events/spamcheck.py
index 56fa9e556e..7b22b3413a 100644
--- a/synapse/events/spamcheck.py
+++ b/synapse/events/spamcheck.py
@@ -13,26 +13,29 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+class SpamChecker(object):
+    def __init__(self, hs):
+        self.spam_checker = None
 
-def check_event_for_spam(event):
-    """Checks if a given event is considered "spammy" by this server.
+        if hs.config.spam_checker is not None:
+            module, config = hs.config.spam_checker
+            print("cfg %r", config)
+            self.spam_checker = module(config=config)
 
-    If the server considers an event spammy, then it will be rejected if
-    sent by a local user. If it is sent by a user on another server, then
-    users receive a blank event.
+    def check_event_for_spam(self, event):
+        """Checks if a given event is considered "spammy" by this server.
 
-    Args:
-        event (synapse.events.EventBase): the event to be checked
+        If the server considers an event spammy, then it will be rejected if
+        sent by a local user. If it is sent by a user on another server, then
+        users receive a blank event.
 
-    Returns:
-        bool: True if the event is spammy.
-    """
-    if not hasattr(event, "content") or "body" not in event.content:
-        return False
+        Args:
+            event (synapse.events.EventBase): the event to be checked
 
-    # for example:
-    #
-    # if "the third flower is green" in event.content["body"]:
-    #    return True
+        Returns:
+            bool: True if the event is spammy.
+        """
+        if self.spam_checker is None:
+            return False
 
-    return False
+        return self.spam_checker.check_event_for_spam(event)
diff --git a/synapse/federation/federation_base.py b/synapse/federation/federation_base.py
index babd9ea078..a0f5d40eb3 100644
--- a/synapse/federation/federation_base.py
+++ b/synapse/federation/federation_base.py
@@ -16,7 +16,6 @@ import logging
 
 from synapse.api.errors import SynapseError
 from synapse.crypto.event_signing import check_event_content_hash
-from synapse.events import spamcheck
 from synapse.events.utils import prune_event
 from synapse.util import unwrapFirstError, logcontext
 from twisted.internet import defer
@@ -26,7 +25,7 @@ logger = logging.getLogger(__name__)
 
 class FederationBase(object):
     def __init__(self, hs):
-        pass
+        self.spam_checker = hs.get_spam_checker()
 
     @defer.inlineCallbacks
     def _check_sigs_and_hash_and_fetch(self, origin, pdus, outlier=False,
@@ -144,7 +143,7 @@ class FederationBase(object):
                     )
                     return redacted
 
-                if spamcheck.check_event_for_spam(pdu):
+                if self.spam_checker.check_event_for_spam(pdu):
                     logger.warn(
                         "Event contains spam, redacting %s: %s",
                         pdu.event_id, pdu.get_pdu_json()
diff --git a/synapse/handlers/message.py b/synapse/handlers/message.py
index da18bf23db..37f0a2772a 100644
--- a/synapse/handlers/message.py
+++ b/synapse/handlers/message.py
@@ -12,7 +12,6 @@
 # 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.events import spamcheck
 from twisted.internet import defer
 
 from synapse.api.constants import EventTypes, Membership
@@ -58,6 +57,8 @@ class MessageHandler(BaseHandler):
 
         self.action_generator = hs.get_action_generator()
 
+        self.spam_checker = hs.get_spam_checker()
+
     @defer.inlineCallbacks
     def purge_history(self, room_id, event_id):
         event = yield self.store.get_event(event_id)
@@ -322,7 +323,7 @@ class MessageHandler(BaseHandler):
             txn_id=txn_id
         )
 
-        if spamcheck.check_event_for_spam(event):
+        if self.spam_checker.check_event_for_spam(event):
             raise SynapseError(
                 403, "Spam is not permitted here", Codes.FORBIDDEN
             )
diff --git a/synapse/server.py b/synapse/server.py
index a38e5179e0..4d44af745e 100644
--- a/synapse/server.py
+++ b/synapse/server.py
@@ -31,6 +31,7 @@ from synapse.appservice.api import ApplicationServiceApi
 from synapse.appservice.scheduler import ApplicationServiceScheduler
 from synapse.crypto.keyring import Keyring
 from synapse.events.builder import EventBuilderFactory
+from synapse.events.spamcheck import SpamChecker
 from synapse.federation import initialize_http_replication
 from synapse.federation.send_queue import FederationRemoteSendQueue
 from synapse.federation.transport.client import TransportLayerClient
@@ -139,6 +140,7 @@ class HomeServer(object):
         'read_marker_handler',
         'action_generator',
         'user_directory_handler',
+        'spam_checker',
     ]
 
     def __init__(self, hostname, **kwargs):
@@ -309,6 +311,9 @@ class HomeServer(object):
     def build_user_directory_handler(self):
         return UserDirectoyHandler(self)
 
+    def build_spam_checker(self):
+        return SpamChecker(self)
+
     def remove_pusher(self, app_id, push_key, user_id):
         return self.get_pusherpool().remove_pusher(app_id, push_key, user_id)
 
-- 
cgit 1.5.1


From adec03395d1c9a8e237a74ea420966bae8ea0002 Mon Sep 17 00:00:00 2001
From: Erik Johnston <erik@matrix.org>
Date: Wed, 27 Sep 2017 15:01:25 +0100
Subject: Fix bug where /joined_members didn't check user was in room

---
 synapse/handlers/message.py    | 31 +++++++++++++++++++++++++++++++
 synapse/rest/client/v1/room.py | 17 +++++++----------
 2 files changed, 38 insertions(+), 10 deletions(-)

(limited to 'synapse/handlers')

diff --git a/synapse/handlers/message.py b/synapse/handlers/message.py
index 37f0a2772a..f6740544c1 100644
--- a/synapse/handlers/message.py
+++ b/synapse/handlers/message.py
@@ -419,6 +419,37 @@ class MessageHandler(BaseHandler):
             [serialize_event(c, now) for c in room_state.values()]
         )
 
+    @defer.inlineCallbacks
+    def get_joined_members(self, user_id, room_id):
+        """Get all the joined members in the room and their profile information.
+
+        If the user has left the room return the state events from when they left.
+
+        Args:
+            user_id(str): The user requesting state events.
+            room_id(str): The room ID to get all state events from.
+        Returns:
+            A dict of user_id to profile info
+        """
+        membership, membership_event_id = yield self._check_in_room_or_world_readable(
+            room_id, user_id
+        )
+
+        if membership == Membership.JOIN:
+            users_with_profile = yield self.state.get_current_user_in_room(room_id)
+        else:
+            raise NotImplementedError(
+                "Getting joined members after leaving is not implemented"
+            )
+
+        defer.returnValue({
+            user_id: {
+                "avatar_url": profile.avatar_url,
+                "display_name": profile.display_name,
+            }
+            for user_id, profile in users_with_profile.iteritems()
+        })
+
     @measure_func("_create_new_client_event")
     @defer.inlineCallbacks
     def _create_new_client_event(self, builder, requester=None, prev_event_ids=None):
diff --git a/synapse/rest/client/v1/room.py b/synapse/rest/client/v1/room.py
index cd388770c8..4be0fee38d 100644
--- a/synapse/rest/client/v1/room.py
+++ b/synapse/rest/client/v1/room.py
@@ -398,22 +398,19 @@ class JoinedRoomMemberListRestServlet(ClientV1RestServlet):
 
     def __init__(self, hs):
         super(JoinedRoomMemberListRestServlet, self).__init__(hs)
-        self.state = hs.get_state_handler()
+        self.message_handler = hs.get_handlers().message_handler
 
     @defer.inlineCallbacks
     def on_GET(self, request, room_id):
-        yield self.auth.get_user_by_req(request)
+        requester = yield self.auth.get_user_by_req(request)
+        user_id = requester.user.to_string()
 
-        users_with_profile = yield self.state.get_current_user_in_room(room_id)
+        users_with_profile = yield self.message_handler.get_joined_members(
+            user_id, room_id,
+        )
 
         defer.returnValue((200, {
-            "joined": {
-                user_id: {
-                    "avatar_url": profile.avatar_url,
-                    "display_name": profile.display_name,
-                }
-                for user_id, profile in users_with_profile.iteritems()
-            }
+            "joined": users_with_profile,
         }))
 
 
-- 
cgit 1.5.1


From 8090fd4664de87bad636ace6774dad8c33bd5276 Mon Sep 17 00:00:00 2001
From: Erik Johnston <erik@matrix.org>
Date: Thu, 28 Sep 2017 10:09:32 +0100
Subject: Fix /joined_members to work with AS users

---
 synapse/handlers/message.py    | 36 +++++++++++++++++++++++++-----------
 synapse/rest/client/v1/room.py |  3 +--
 2 files changed, 26 insertions(+), 13 deletions(-)

(limited to 'synapse/handlers')

diff --git a/synapse/handlers/message.py b/synapse/handlers/message.py
index f6740544c1..ca8c6c55bb 100644
--- a/synapse/handlers/message.py
+++ b/synapse/handlers/message.py
@@ -420,27 +420,41 @@ class MessageHandler(BaseHandler):
         )
 
     @defer.inlineCallbacks
-    def get_joined_members(self, user_id, room_id):
+    def get_joined_members(self, requester, room_id):
         """Get all the joined members in the room and their profile information.
 
         If the user has left the room return the state events from when they left.
 
         Args:
-            user_id(str): The user requesting state events.
+            requester(Requester): The user requesting state events.
             room_id(str): The room ID to get all state events from.
         Returns:
             A dict of user_id to profile info
         """
-        membership, membership_event_id = yield self._check_in_room_or_world_readable(
-            room_id, user_id
-        )
-
-        if membership == Membership.JOIN:
-            users_with_profile = yield self.state.get_current_user_in_room(room_id)
-        else:
-            raise NotImplementedError(
-                "Getting joined members after leaving is not implemented"
+        user_id = requester.user.to_string()
+        if not requester.app_service:
+            # We check AS auth after fetching the room membership, as it
+            # requires us to pull out all joined members anyway.
+            membership, _ = yield self._check_in_room_or_world_readable(
+                room_id, user_id
             )
+            if membership != Membership.JOIN:
+                raise NotImplementedError(
+                    "Getting joined members after leaving is not implemented"
+                )
+
+        users_with_profile = yield self.state.get_current_user_in_room(room_id)
+
+        # If this is an AS, double check that they are allowed to see the members.
+        # This can either be because the AS user is in the room or becuase there
+        # is a user in the room that the AS is "interested in"
+        if requester.app_service and user_id not in users_with_profile:
+            for uid in users_with_profile:
+                if requester.app_service.is_interested_in_user(uid):
+                    break
+            else:
+                # Loop fell through, AS has no interested users in room
+                raise AuthError(403, "Appservice not in room")
 
         defer.returnValue({
             user_id: {
diff --git a/synapse/rest/client/v1/room.py b/synapse/rest/client/v1/room.py
index 4be0fee38d..6c379d53ac 100644
--- a/synapse/rest/client/v1/room.py
+++ b/synapse/rest/client/v1/room.py
@@ -403,10 +403,9 @@ class JoinedRoomMemberListRestServlet(ClientV1RestServlet):
     @defer.inlineCallbacks
     def on_GET(self, request, room_id):
         requester = yield self.auth.get_user_by_req(request)
-        user_id = requester.user.to_string()
 
         users_with_profile = yield self.message_handler.get_joined_members(
-            user_id, room_id,
+            requester, room_id,
         )
 
         defer.returnValue((200, {
-- 
cgit 1.5.1