1 <?php

     2 /**

     3  * HTTP API: WP_HTTP_Proxy class

     4  *

     5  * @package WordPress

     6  * @subpackage HTTP

     7  * @since 4.4.0

     8  */

     9 

    10 /**

    11  * Core class used to implement HTTP API proxy support.

    12  *

    13  * There are caveats to proxy support. It requires that defines be made in the wp-config.php file to

    14  * enable proxy support. There are also a few filters that plugins can hook into for some of the

    15  * constants.

    16  *

    17  * Please note that only BASIC authentication is supported by most transports.

    18  * cURL MAY support more methods (such as NTLM authentication) depending on your environment.

    19  *

    20  * The constants are as follows:

    21  * <ol>

    22  * <li>WP_PROXY_HOST - Enable proxy support and host for connecting.</li>

    23  * <li>WP_PROXY_PORT - Proxy port for connection. No default, must be defined.</li>

    24  * <li>WP_PROXY_USERNAME - Proxy username, if it requires authentication.</li>

    25  * <li>WP_PROXY_PASSWORD - Proxy password, if it requires authentication.</li>

    26  * <li>WP_PROXY_BYPASS_HOSTS - Will prevent the hosts in this list from going through the proxy.

    27  * You do not need to have localhost and the site host in this list, because they will not be passed

    28  * through the proxy. The list should be presented in a comma separated list, wildcards using * are supported, eg. *.wordpress.org</li>

    29  * </ol>

    30  *

    31  * An example can be as seen below.

    32  *

    33  *     define('WP_PROXY_HOST', '192.168.84.101');

    34  *     define('WP_PROXY_PORT', '8080');

    35  *     define('WP_PROXY_BYPASS_HOSTS', 'localhost, www.example.com, *.wordpress.org');

    36  *

    37  * @link https://core.trac.wordpress.org/ticket/4011 Proxy support ticket in WordPress.

    38  * @link https://core.trac.wordpress.org/ticket/14636 Allow wildcard domains in WP_PROXY_BYPASS_HOSTS

    39  *

    40  * @since 2.8.0

    41  */

    42 class WP_HTTP_Proxy {

    43 

    44 	/**

    45 	 * Whether proxy connection should be used.

    46 	 *

    47 	 * @since 2.8.0

    48 	 *

    49 	 * @use WP_PROXY_HOST

    50 	 * @use WP_PROXY_PORT

    51 	 *

    52 	 * @return bool

    53 	 */

    54 	public function is_enabled() {

    55 		return defined('WP_PROXY_HOST') && defined('WP_PROXY_PORT');

    56 	}

    57 

    58 	/**

    59 	 * Whether authentication should be used.

    60 	 *

    61 	 * @since 2.8.0

    62 	 *

    63 	 * @use WP_PROXY_USERNAME

    64 	 * @use WP_PROXY_PASSWORD

    65 	 *

    66 	 * @return bool

    67 	 */

    68 	public function use_authentication() {

    69 		return defined('WP_PROXY_USERNAME') && defined('WP_PROXY_PASSWORD');

    70 	}

    71 

    72 	/**

    73 	 * Retrieve the host for the proxy server.

    74 	 *

    75 	 * @since 2.8.0

    76 	 *

    77 	 * @return string

    78 	 */

    79 	public function host() {

    80 		if ( defined('WP_PROXY_HOST') )

    81 			return WP_PROXY_HOST;

    82 

    83 		return '';

    84 	}

    85 

    86 	/**

    87 	 * Retrieve the port for the proxy server.

    88 	 *

    89 	 * @since 2.8.0

    90 	 *

    91 	 * @return string

    92 	 */

    93 	public function port() {

    94 		if ( defined('WP_PROXY_PORT') )

    95 			return WP_PROXY_PORT;

    96 

    97 		return '';

    98 	}

    99 

   100 	/**

   101 	 * Retrieve the username for proxy authentication.

   102 	 *

   103 	 * @since 2.8.0

   104 	 *

   105 	 * @return string

   106 	 */

   107 	public function username() {

   108 		if ( defined('WP_PROXY_USERNAME') )

   109 			return WP_PROXY_USERNAME;

   110 

   111 		return '';

   112 	}

   113 

   114 	/**

   115 	 * Retrieve the password for proxy authentication.

   116 	 *

   117 	 * @since 2.8.0

   118 	 *

   119 	 * @return string

   120 	 */

   121 	public function password() {

   122 		if ( defined('WP_PROXY_PASSWORD') )

   123 			return WP_PROXY_PASSWORD;

   124 

   125 		return '';

   126 	}

   127 

   128 	/**

   129 	 * Retrieve authentication string for proxy authentication.

   130 	 *

   131 	 * @since 2.8.0

   132 	 *

   133 	 * @return string

   134 	 */

   135 	public function authentication() {

   136 		return $this->username() . ':' . $this->password();

   137 	}

   138 

   139 	/**

   140 	 * Retrieve header string for proxy authentication.

   141 	 *

   142 	 * @since 2.8.0

   143 	 *

   144 	 * @return string

   145 	 */

   146 	public function authentication_header() {

   147 		return 'Proxy-Authorization: Basic ' . base64_encode( $this->authentication() );

   148 	}

   149 

   150 	/**

   151 	 * Whether URL should be sent through the proxy server.

   152 	 *

   153 	 * We want to keep localhost and the site URL from being sent through the proxy server, because

   154 	 * some proxies can not handle this. We also have the constant available for defining other

   155 	 * hosts that won't be sent through the proxy.

   156 	 *

   157 	 * @since 2.8.0

   158 	 *

   159 	 * @staticvar array|null $bypass_hosts

   160 	 * @staticvar array      $wildcard_regex

   161 	 *

   162 	 * @param string $uri URI to check.

   163 	 * @return bool True, to send through the proxy and false if, the proxy should not be used.

   164 	 */

   165 	public function send_through_proxy( $uri ) {

   166 		/*

   167 		 * parse_url() only handles http, https type URLs, and will emit E_WARNING on failure.

   168 		 * This will be displayed on sites, which is not reasonable.

   169 		 */

   170 		$check = @parse_url($uri);

   171 

   172 		// Malformed URL, can not process, but this could mean ssl, so let through anyway.

   173 		if ( $check === false )

   174 			return true;

   175 

   176 		$home = parse_url( get_option('siteurl') );

   177 

   178 		/**

   179 		 * Filters whether to preempt sending the request through the proxy server.

   180 		 *

   181 		 * Returning false will bypass the proxy; returning true will send

   182 		 * the request through the proxy. Returning null bypasses the filter.

   183 		 *

   184 		 * @since 3.5.0

   185 		 *

   186 		 * @param null   $override Whether to override the request result. Default null.

   187 		 * @param string $uri      URL to check.

   188 		 * @param array  $check    Associative array result of parsing the URI.

   189 		 * @param array  $home     Associative array result of parsing the site URL.

   190 		 */

   191 		$result = apply_filters( 'pre_http_send_through_proxy', null, $uri, $check, $home );

   192 		if ( ! is_null( $result ) )

   193 			return $result;

   194 

   195 		if ( 'localhost' == $check['host'] || ( isset( $home['host'] ) && $home['host'] == $check['host'] ) )

   196 			return false;

   197 

   198 		if ( !defined('WP_PROXY_BYPASS_HOSTS') )

   199 			return true;

   200 

   201 		static $bypass_hosts = null;

   202 		static $wildcard_regex = array();

   203 		if ( null === $bypass_hosts ) {

   204 			$bypass_hosts = preg_split('|,\s*|', WP_PROXY_BYPASS_HOSTS);

   205 

   206 			if ( false !== strpos(WP_PROXY_BYPASS_HOSTS, '*') ) {

   207 				$wildcard_regex = array();

   208 				foreach ( $bypass_hosts as $host )

   209 					$wildcard_regex[] = str_replace( '\*', '.+', preg_quote( $host, '/' ) );

   210 				$wildcard_regex = '/^(' . implode('|', $wildcard_regex) . ')$/i';

   211 			}

   212 		}

   213 

   214 		if ( !empty($wildcard_regex) )

   215 			return !preg_match($wildcard_regex, $check['host']);

   216 		else

   217 			return !in_array( $check['host'], $bypass_hosts );

   218 	}

   219 }