From ae67ff7a37f0e66acef4455d6dbca489d2d051b4 Mon Sep 17 00:00:00 2001
From: Erik Johnston <erik@matrix.org>
Date: Fri, 13 Nov 2020 17:51:48 +0000
Subject: [PATCH] Allow server admin to get admin bit in room

---
 synapse/rest/admin/rooms.py | 101 +++++++++++++++++++++++++++++++++++-
 1 file changed, 99 insertions(+), 2 deletions(-)

diff --git a/synapse/rest/admin/rooms.py b/synapse/rest/admin/rooms.py
index f5304ff43d..40891f9226 100644
--- a/synapse/rest/admin/rooms.py
+++ b/synapse/rest/admin/rooms.py
@@ -14,9 +14,9 @@
 # limitations under the License.
 import logging
 from http import HTTPStatus
-from typing import List, Optional
+from typing import TYPE_CHECKING, List, Optional
 
-from synapse.api.constants import EventTypes, JoinRules
+from synapse.api.constants import EventTypes, JoinRules, Membership
 from synapse.api.errors import Codes, NotFoundError, SynapseError
 from synapse.http.servlet import (
     RestServlet,
@@ -34,6 +34,9 @@ from synapse.rest.admin._base import (
 from synapse.storage.databases.main.room import RoomSortOrder
 from synapse.types import RoomAlias, RoomID, UserID, create_requester
 
+if TYPE_CHECKING:
+    from synapse.server import HomeServer
+
 logger = logging.getLogger(__name__)
 
 
@@ -338,3 +341,97 @@ class JoinRoomAliasServlet(RestServlet):
         )
 
         return 200, {"room_id": room_id}
+
+
+class MakeRoomAdminRoomServlet(RestServlet):
+    PATTERNS = admin_patterns("/make_room_admin/(?P<room_identifier>[^/]*)")
+
+    def __init__(self, hs: "HomeServer"):
+        self.hs = hs
+        self.auth = hs.get_auth()
+        self.room_member_handler = hs.get_room_member_handler()
+        self.event_creation_handler = hs.get_event_creation_handler()
+        self.state_handler = hs.get_state_handler()
+        self.is_mine_id = hs.is_mine_id
+
+    async def on_POST(self, request, room_identifier):
+        requester = await self.auth.get_user_by_req(request)
+        await assert_user_is_admin(self.auth, requester.user)
+        content = parse_json_object_from_request(request, allow_empty_body=True)
+
+        if RoomID.is_valid(room_identifier):
+            room_id = room_identifier
+        elif RoomAlias.is_valid(room_identifier):
+            room_alias = RoomAlias.from_string(room_identifier)
+            room_id, _ = await self.room_member_handler.lookup_room_alias(room_alias)
+            room_id = room_id.to_string()
+        else:
+            raise SynapseError(
+                400, "%s was not legal room ID or room alias" % (room_identifier,)
+            )
+
+        user_to_add = content.get("user_id", requester.user.to_string())
+
+        room_state = await self.state_handler.get_current_state(room_id)
+
+        if not room_state:
+            raise SynapseError(400, "Server not in room")
+
+        create_event = room_state[(EventTypes.Create, "")]
+        power_levels = room_state.get((EventTypes.PowerLevels, ""))
+
+        if power_levels is not None:
+            admin_users = [
+                user_id
+                for user_id, power in power_levels.content.get("users")
+                if self.is_mine_id(user_id)
+            ]
+            admin_users.sort(key=lambda user: power_levels.content.get("users")[user])
+
+            admin_user_id = admin_users[-1]
+
+            pl_content = power_levels.content
+        else:
+            admin_user_id = create_event.sender
+            if not self.is_mine_id(admin_user_id):
+                raise SynapseError(400, "No local admin user in room")
+
+        fake_requester = create_requester(
+            admin_user_id, authenticated_entity=requester.authenticated_entity,
+        )
+
+        new_pl_content = dict(pl_content)
+        new_pl_content["users"] = dict(pl_content.get("users", {}))
+        new_pl_content["users"][user_to_add] = new_pl_content["users"][admin_user_id]
+
+        await self.event_creation_handler.create_and_send_nonmember_event(
+            fake_requester, event_dict=new_pl_content,
+        )
+
+        member_event = room_state.get((EventTypes.Member, user_to_add))
+        is_joined = False
+        if member_event:
+            is_joined = member_event.content["membership"] in (
+                Membership.JOIN,
+                Membership.INVITE,
+            )
+
+        if is_joined:
+            return 200, {}
+
+        join_rules = room_state.get((EventTypes.JoinRules, ""))
+        is_public = False
+        if join_rules:
+            is_public = join_rules.content.get("join_rule") == JoinRules.PUBLIC
+
+        if is_public:
+            return 200, {}
+
+        await self.room_member_handler.update_membership(
+            fake_requester,
+            target=UserID.from_string(user_to_add),
+            room_id=room_id,
+            action=Membership.INVITE,
+        )
+
+        return 200, {}