Fix owner being able to add more users to a password request room

Only the owner and another participant will be allowed to join a
password request room, so there is no point in being able to add more
participants to those rooms.

Although throwing the exception in the listener is enough to prevent
adding the participants unhandled exceptions in the endpoint are
returned as error 404, but the expected error would be 400. To minimize
conflicts with other pull requests and backports it is explicitly
checked if the room is a password request room instead of refactoring
the code to handle the exception.

Signed-off-by: Daniel Calviño Sánchez <[email protected]>

docs/participant.md

@@ -48,7 +48,7 @@ Base endpoint is: `/ocs/v2.php/apps/spreed/api/v1`
     - Status code:
         + `200 OK`
         + `400 Bad Request` When the source type is unknown, currently `users`, `groups`, `emails` are supported. `circles` are supported with `circles-support` capability
-        + `400 Bad Request` When the conversation is a one-to-one conversation
+        + `400 Bad Request` When the conversation is a one-to-one conversation or a conversation to request a password for a share
         + `403 Forbidden` When the current user is not a moderator or owner
         + `404 Not Found` When the conversation could not be found for the participant
         + `404 Not Found` When the user or group to add could not be found

lib/Controller/RoomController.php

@@ -944,7 +944,7 @@ public function getParticipants(bool $includeStatus = false): DataResponse {
 	 * @return DataResponse
 	 */
 	public function addParticipantToRoom(string $newParticipant, string $source = 'users'): DataResponse {
-		if ($this->room->getType() === Room::ONE_TO_ONE_CALL) {
+		if ($this->room->getType() === Room::ONE_TO_ONE_CALL || $this->room->getObjectType() === 'share:password') {
 			return new DataResponse([], Http::STATUS_BAD_REQUEST);
 		}
 

lib/PublicShareAuth/Listener.php

@@ -24,6 +24,7 @@
 
 namespace OCA\Talk\PublicShareAuth;
 
+use OCA\Talk\Events\AddParticipantsEvent;
 use OCA\Talk\Events\JoinRoomGuestEvent;
 use OCA\Talk\Events\JoinRoomUserEvent;
 use OCA\Talk\Events\RoomEvent;
@@ -57,6 +58,11 @@ public static function register(IEventDispatcher $dispatcher): void {
 		};
 		$dispatcher->addListener(Room::EVENT_BEFORE_GUEST_CONNECT, $listener);
 
+		$listener = static function (AddParticipantsEvent $event) {
+			self::preventExtraUsersFromBeingAdded($event->getRoom(), $event->getParticipants());
+		};
+		$dispatcher->addListener(Room::EVENT_BEFORE_USERS_ADD, $listener);
+
 		$listener = static function (RoomEvent $event) {
 			self::destroyRoomOnParticipantLeave($event->getRoom());
 		};
@@ -113,6 +119,34 @@ public static function preventExtraGuestsFromJoining(Room $room): void {
 		}
 	}
 
+	/**
+	 * Prevents other users from being added to the room (as they will not be
+	 * able to join).
+	 *
+	 * This method should be called before a user is added to a room.
+	 *
+	 * @param Room $room
+	 * @param array[] $participants
+	 * @throws \OverflowException
+	 */
+	public static function preventExtraUsersFromBeingAdded(Room $room, array $participants): void {
+		if ($room->getObjectType() !== 'share:password') {
+			return;
+		}
+
+		// Events with more than one participant can be directly aborted, as
+		// when the owner is added during room creation or a user self-joins the
+		// event will always have just one participant.
+		if (count($participants) > 1) {
+			throw new \OverflowException('Only the owner and another participant are allowed in rooms to request the password for a share');
+		}
+
+		$participant = $participants[0];
+		if ($participant['participantType'] !== Participant::OWNER && $participant['participantType'] !== Participant::USER_SELF_JOINED) {
+			throw new \OverflowException('Only the owner and another participant are allowed in rooms to request the password for a share');
+		}
+	}
+
 	/**
 	 * Destroys the PublicShareAuth room as soon as one of the participant
 	 * leaves the room.

tests/integration/features/conversation/password-request.feature

@@ -113,6 +113,17 @@ Feature: conversation/password-request
 
 
 
+  Scenario: owner can not add other users to a password request room
+    Given user "participant1" shares "welcome.txt" by link with OCS 100
+      | password | 123456 |
+      | sendPasswordByTalk | true |
+    And user "guest" creates the password request room for last share with 201
+    And user "participant1" joins room "password request for last share room" with 200
+    When user "participant1" adds "participant2" to room "password request for last share room" with 400
+    Then user "participant2" is not participant of room "password request for last share room"
+
+
+
   Scenario: guest leaves the password request room
     Given user "participant1" shares "welcome.txt" by link with OCS 100
       | password | 123456 |