owncloud/core

<?php
/**
 * @author Björn Schießle <bjoern@schiessle.org>
 * @author Thomas Müller <thomas.mueller@tmit.eu>
 *
 * @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 OCA\FederatedFileSharing;
use OC\HintException;
use OCP\IL10N;
use OCP\IURLGenerator;

/**
 * Class AddressHandler - parse, modify and construct federated sharing addresses
 *
 * @package OCA\FederatedFileSharing
 */
class AddressHandler {
    /** @var IL10N */
    private $l;

    /** @var IURLGenerator */
    private $urlGenerator;

    /**
     * AddressHandler constructor.
     *
     * @param IURLGenerator $urlGenerator
     * @param IL10N $il10n
     */
    public function __construct(
        IURLGenerator $urlGenerator,
        IL10N $il10n
    ) {
        $this->l = $il10n;
        $this->urlGenerator = $urlGenerator;
    }

    /**
     * split user and remote from federated cloud id
     *
     * @param string $address federated share address
     * @return array [user, remoteURL]
     * @throws HintException
     */
    public function splitUserRemote($address) {
        if (\strpos($address, '@') === false) {
            $hint = $this->l->t('Invalid Federated Cloud ID');
            throw new HintException('Invalid Federated Cloud ID', $hint);
        }

        // Find the first character that is not allowed in user names
        $id = \str_replace('\\', '/', $address);
        $posSlash = \strpos($id, '/');
        $posColon = \strpos($id, ':');

        if ($posSlash === false && $posColon === false) {
            $invalidPos = \strlen($id);
        } elseif ($posSlash === false) {
            $invalidPos = $posColon;
        } elseif ($posColon === false) {
            $invalidPos = $posSlash;
        } else {
            $invalidPos = \min($posSlash, $posColon);
        }

        // Find the last @ before $invalidPos
        $pos = $lastAtPos = 0;
        while ($lastAtPos !== false && $lastAtPos <= $invalidPos) {
            $pos = $lastAtPos;
            $lastAtPos = \strpos($id, '@', $pos + 1);
        }

        if ($pos !== false) {
            $user = \substr($id, 0, $pos);
            $remote = \substr($id, $pos + 1);
            $remote = $this->fixRemoteURL($remote);
            if (!empty($user) && !empty($remote)) {
                return [$user, $remote];
            }
        }

        $hint = $this->l->t('Invalid Federated Cloud ID');
        throw new HintException('Invalid Federated Cloud ID', $hint);
    }

    /**
     * @param string $uid
     *
     * @return Address
     */
    public function getLocalUserFederatedAddress($uid) {
        $host = $this->generateRemoteURL();
        return new Address("{$uid}@{$host}");
    }

    /**
     * generate remote URL part of federated ID
     *
     * @return string url of the current server
     */
    public function generateRemoteURL() {
        $url = $this->urlGenerator->getAbsoluteURL('/');
        return $url;
    }

    /**
     * remove protocol from URL
     *
     * @param string $url
     * @return string
     */
    public function removeProtocolFromUrl($url) {
        // replace all characters before :// and :// itself
        return \preg_replace('|^(.*?://)|', '', $url);
    }

    /**
     * Strips away a potential file names and trailing slashes:
     * - http://localhost
     * - http://localhost/
     * - http://localhost/index.php
     * - http://localhost/index.php/s/{shareToken}
     *
     * all return: http://localhost
     *
     * @param string $remote
     * @return string
     */
    protected function fixRemoteURL($remote) {
        $remote = \str_replace('\\', '/', $remote);
        if ($fileNamePosition = \strpos($remote, '/index.php')) {
            $remote = \substr($remote, 0, $fileNamePosition);
        }
        $remote = \rtrim($remote, '/');

        return $remote;
    }
}