owncloud/core

<?php
/**
 * @author Björn Schießle <bjoern@schiessle.org>
 * @author Thomas Müller <thomas.mueller@tmit.eu>
 * @author Vincent Petry <pvince81@owncloud.com>
 *
 * @copyright Copyright (c) 2018, ownCloud GmbH
 * @license AGPL-3.0
 *
 * This code is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License, version 3,
 * as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License, version 3,
 * along with this program.  If not, see <http://www.gnu.org/licenses/>
 *
 */

namespace OC\Encryption;

use OC\Cache\CappedMemoryCache;
use OC_Util;

class File implements \OCP\Encryption\IFile {
    /** @var Util */
    protected $util;

    /**
     * cache results of already checked folders
     *
     * @var array
     */
    protected $cache;

    public function __construct(Util $util) {
        $this->util = $util;
        $this->cache = new CappedMemoryCache();
    }

    /**
     * get list of users with access to the file
     *
     * @param string $path to the file
     * @return array  ['users' => $uniqueUserIds, 'public' => $public]
     */
    public function getAccessList($path) {
        // Make sure that a share key is generated for the owner too
        list($owner, $ownerPath) = $this->util->getUidAndFilename($path);

        // always add owner to the list of users with access to the file
        $userIds = [$owner];

        if (!$this->util->isFile($owner . '/' . $ownerPath)) {
            return ['users' => $userIds, 'public' => false];
        }

        $ownerPath = \substr($ownerPath, \strlen('/files'));
        $ownerPath = OC_Util::stripPartialFileExtension($ownerPath);

        // first get the shares for the parent and cache the result so that we don't
        // need to check all parents for every file
        $parent = \dirname($ownerPath);
        if (isset($this->cache[$parent])) {
            $resultForParents = $this->cache[$parent];
        } else {
            $resultForParents = \OCP\Share::getUsersSharingFile($parent, $owner);
            $this->cache[$parent] = $resultForParents;
        }
        $userIds = \array_merge($userIds, $resultForParents['users']);
        $public = $resultForParents['public'] || $resultForParents['remote'];

        // Find out who, if anyone, is sharing the file
        $resultForFile = \OCP\Share::getUsersSharingFile($ownerPath, $owner, false, false, false);
        $userIds = \array_merge($userIds, $resultForFile['users']);
        $public = $resultForFile['public'] || $resultForFile['remote'] || $public;

        // check if it is a group mount
        if (\OCP\App::isEnabled("files_external")) {
            $mounts = \OC\Files\External\LegacyUtil::getSystemMountPoints();
            foreach ($mounts as $mount) {
                if ($mount['mountpoint'] == \substr($ownerPath, 1, \strlen($mount['mountpoint']))) {
                    $mountedFor = $this->util->getUserWithAccessToMountPoint($mount['applicable']['users'], $mount['applicable']['groups']);
                    $userIds = \array_merge($userIds, $mountedFor);
                }
            }
        }

        // Remove duplicate UIDs
        $uniqueUserIds = \array_unique($userIds);

        return ['users' => $uniqueUserIds, 'public' => $public];
    }
}