Proyectos de Subversion Moodle

<?php

/**

 * Licensed to Jasig under one or more contributor license

 * agreements. See the NOTICE file distributed with this work for

 * additional information regarding copyright ownership.

 *

 * Jasig licenses this file to you under the Apache License,

 * Version 2.0 (the "License"); you may not use this file except in

 * compliance with the License. You may obtain a copy of the License at:

 *

 * http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * 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.

 *

 * PHP Version 7

 *

 * @file     CAS/ServiceBaseUrl/AllowedListDiscovery.php

 * @category Authentication

 * @package  PhpCAS

 * @author   Henry Pan <git@phy25.com>

 * @license  http://www.apache.org/licenses/LICENSE-2.0  Apache License 2.0

 * @link     https://wiki.jasig.org/display/CASC/phpCAS

 */

/**

 * Class that gets the service base URL of the PHP server by HTTP header

 * discovery and allowlist check. This is used to generate service URL

 * and PGT callback URL.

 *

 * @class    CAS_ServiceBaseUrl_AllowedListDiscovery

 * @category Authentication

 * @package  PhpCAS

 * @author   Henry Pan <git@phy25.com>

 * @license  http://www.apache.org/licenses/LICENSE-2.0  Apache License 2.0

 * @link     https://wiki.jasig.org/display/CASC/phpCAS

 */

class CAS_ServiceBaseUrl_AllowedListDiscovery

extends CAS_ServiceBaseUrl_Base

{

    private $_list = array();

    public function __construct($list) {

        if (is_array($list)) {

            if (count($list) === 0) {

                throw new CAS_InvalidArgumentException('$list should not be empty');

            }

            foreach ($list as $value) {

                $this->allow($value);

            }

        } else {

            throw new CAS_TypeMismatchException($list, '$list', 'array');

        }

    }

    /**

     * Add a base URL to the allowed list.

     *

     * @param $url protocol, host name and port to add to the allowed list

     *

     * @return void

     */

    public function allow($url)

    {

        $this->_list[] = $this->removeStandardPort($url);

    }

    /**

     * Check if the server name is allowed by configuration.

     *

     * @param $name server name to check

     *

     * @return bool whether the allowed list contains the server name

     */

    protected function isAllowed($name)

    {

        return in_array($name, $this->_list);

    }

    /**

     * Discover the server name through HTTP headers.

     *

     * We read:

     * - HTTP header X-Forwarded-Host

     * - HTTP header X-Forwarded-Server and X-Forwarded-Port

     * - HTTP header Host and SERVER_PORT

     * - PHP SERVER_NAME (which can change based on the HTTP server used)

     *

     * The standard port will be omitted (80 for HTTP, 443 for HTTPS).

     *

     * @return string the discovered, unsanitized server protocol, hostname and port

     */

    protected function discover()

    {

        $isHttps = $this->isHttps();

        $protocol = $isHttps ? 'https' : 'http';

        $protocol .= '://';

        if (!empty($_SERVER['HTTP_X_FORWARDED_HOST'])) {

            // explode the host list separated by comma and use the first host

            $hosts = explode(',', $_SERVER['HTTP_X_FORWARDED_HOST']);

            // see rfc7239#5.3 and rfc7230#2.7.1: port is in HTTP_X_FORWARDED_HOST if non default

            return $protocol . $hosts[0];

        } else if (!empty($_SERVER['HTTP_X_FORWARDED_SERVER'])) {

            $server_url = $_SERVER['HTTP_X_FORWARDED_SERVER'];

        } else {

            if (empty($_SERVER['SERVER_NAME'])) {

                $server_url = $_SERVER['HTTP_HOST'];

            } else {

                $server_url = $_SERVER['SERVER_NAME'];

            }

        }

        if (!strpos($server_url, ':')) {

            if (empty($_SERVER['HTTP_X_FORWARDED_PORT'])) {

                $server_port = $_SERVER['SERVER_PORT'];

            } else {

                $ports = explode(',', $_SERVER['HTTP_X_FORWARDED_PORT']);

                $server_port = $ports[0];

            }

            $server_url .= ':';

            $server_url .= $server_port;

        }

        return $protocol . $server_url;

    }

    /**

     * Get PHP server base URL.

     *

     * @return string the server protocol, hostname and port

     */

    public function get()

    {

        phpCAS::traceBegin();

        $result = $this->removeStandardPort($this->discover());

        phpCAS::trace("Discovered server base URL: " . $result);

        if ($this->isAllowed($result)) {

            phpCAS::trace("Server base URL is allowed");

            phpCAS::traceEnd(true);

        } else {

            $result = $this->_list[0];

            phpCAS::trace("Server base URL is not allowed, using default: " . $result);

            phpCAS::traceEnd(false);

        }

        return $result;

    }

}