wp/wp-includes/class-wp-recovery-mode-cookie-service.php
changeset 9 177826044cd9
child 16 a86126ab1dd4
equal deleted inserted replaced
8:c7c34916027a 9:177826044cd9
       
     1 <?php
       
     2 /**
       
     3  * Error Protection API: WP_Recovery_Mode_Cookie_Service class
       
     4  *
       
     5  * @package WordPress
       
     6  * @since   5.2.0
       
     7  */
       
     8 
       
     9 /**
       
    10  * Core class used to set, validate, and clear cookies that identify a Recovery Mode session.
       
    11  *
       
    12  * @since 5.2.0
       
    13  */
       
    14 final class WP_Recovery_Mode_Cookie_Service {
       
    15 
       
    16 	/**
       
    17 	 * Checks whether the recovery mode cookie is set.
       
    18 	 *
       
    19 	 * @since 5.2.0
       
    20 	 *
       
    21 	 * @return bool True if the cookie is set, false otherwise.
       
    22 	 */
       
    23 	public function is_cookie_set() {
       
    24 		return ! empty( $_COOKIE[ RECOVERY_MODE_COOKIE ] );
       
    25 	}
       
    26 
       
    27 	/**
       
    28 	 * Sets the recovery mode cookie.
       
    29 	 *
       
    30 	 * This must be immediately followed by exiting the request.
       
    31 	 *
       
    32 	 * @since 5.2.0
       
    33 	 */
       
    34 	public function set_cookie() {
       
    35 
       
    36 		$value = $this->generate_cookie();
       
    37 
       
    38 		setcookie( RECOVERY_MODE_COOKIE, $value, 0, COOKIEPATH, COOKIE_DOMAIN, is_ssl(), true );
       
    39 
       
    40 		if ( COOKIEPATH !== SITECOOKIEPATH ) {
       
    41 			setcookie( RECOVERY_MODE_COOKIE, $value, 0, SITECOOKIEPATH, COOKIE_DOMAIN, is_ssl(), true );
       
    42 		}
       
    43 	}
       
    44 
       
    45 	/**
       
    46 	 * Clears the recovery mode cookie.
       
    47 	 *
       
    48 	 * @since 5.2.0
       
    49 	 */
       
    50 	public function clear_cookie() {
       
    51 		setcookie( RECOVERY_MODE_COOKIE, ' ', time() - YEAR_IN_SECONDS, COOKIEPATH, COOKIE_DOMAIN );
       
    52 		setcookie( RECOVERY_MODE_COOKIE, ' ', time() - YEAR_IN_SECONDS, SITECOOKIEPATH, COOKIE_DOMAIN );
       
    53 	}
       
    54 
       
    55 	/**
       
    56 	 * Validates the recovery mode cookie.
       
    57 	 *
       
    58 	 * @since 5.2.0
       
    59 	 *
       
    60 	 * @param string $cookie Optionally specify the cookie string.
       
    61 	 *                       If omitted, it will be retrieved from the super global.
       
    62 	 * @return true|WP_Error True on success, error object on failure.
       
    63 	 */
       
    64 	public function validate_cookie( $cookie = '' ) {
       
    65 
       
    66 		if ( ! $cookie ) {
       
    67 			if ( empty( $_COOKIE[ RECOVERY_MODE_COOKIE ] ) ) {
       
    68 				return new WP_Error( 'no_cookie', __( 'No cookie present.' ) );
       
    69 			}
       
    70 
       
    71 			$cookie = $_COOKIE[ RECOVERY_MODE_COOKIE ];
       
    72 		}
       
    73 
       
    74 		$parts = $this->parse_cookie( $cookie );
       
    75 
       
    76 		if ( is_wp_error( $parts ) ) {
       
    77 			return $parts;
       
    78 		}
       
    79 
       
    80 		list( , $created_at, $random, $signature ) = $parts;
       
    81 
       
    82 		if ( ! ctype_digit( $created_at ) ) {
       
    83 			return new WP_Error( 'invalid_created_at', __( 'Invalid cookie format.' ) );
       
    84 		}
       
    85 
       
    86 		/**
       
    87 		 * Filter the length of time a Recovery Mode cookie is valid for.
       
    88 		 *
       
    89 		 * @since 5.2.0
       
    90 		 *
       
    91 		 * @param int $length Length in seconds.
       
    92 		 */
       
    93 		$length = apply_filters( 'recovery_mode_cookie_length', WEEK_IN_SECONDS );
       
    94 
       
    95 		if ( time() > $created_at + $length ) {
       
    96 			return new WP_Error( 'expired', __( 'Cookie expired.' ) );
       
    97 		}
       
    98 
       
    99 		$to_sign = sprintf( 'recovery_mode|%s|%s', $created_at, $random );
       
   100 		$hashed  = $this->recovery_mode_hash( $to_sign );
       
   101 
       
   102 		if ( ! hash_equals( $signature, $hashed ) ) {
       
   103 			return new WP_Error( 'signature_mismatch', __( 'Invalid cookie.' ) );
       
   104 		}
       
   105 
       
   106 		return true;
       
   107 	}
       
   108 
       
   109 	/**
       
   110 	 * Gets the session identifier from the cookie.
       
   111 	 *
       
   112 	 * The cookie should be validated before calling this API.
       
   113 	 *
       
   114 	 * @since 5.2.0
       
   115 	 *
       
   116 	 * @param string $cookie Optionally specify the cookie string.
       
   117 	 *                       If omitted, it will be retrieved from the super global.
       
   118 	 * @return string|WP_Error Session ID on success, or error object on failure.
       
   119 	 */
       
   120 	public function get_session_id_from_cookie( $cookie = '' ) {
       
   121 		if ( ! $cookie ) {
       
   122 			if ( empty( $_COOKIE[ RECOVERY_MODE_COOKIE ] ) ) {
       
   123 				return new WP_Error( 'no_cookie', __( 'No cookie present.' ) );
       
   124 			}
       
   125 
       
   126 			$cookie = $_COOKIE[ RECOVERY_MODE_COOKIE ];
       
   127 		}
       
   128 
       
   129 		$parts = $this->parse_cookie( $cookie );
       
   130 		if ( is_wp_error( $parts ) ) {
       
   131 			return $parts;
       
   132 		}
       
   133 
       
   134 		list( , , $random ) = $parts;
       
   135 
       
   136 		return sha1( $random );
       
   137 	}
       
   138 
       
   139 	/**
       
   140 	 * Parses the cookie into its four parts.
       
   141 	 *
       
   142 	 * @since 5.2.0
       
   143 	 *
       
   144 	 * @param string $cookie Cookie content.
       
   145 	 * @return array|WP_Error Cookie parts array, or error object on failure.
       
   146 	 */
       
   147 	private function parse_cookie( $cookie ) {
       
   148 		$cookie = base64_decode( $cookie );
       
   149 		$parts  = explode( '|', $cookie );
       
   150 
       
   151 		if ( 4 !== count( $parts ) ) {
       
   152 			return new WP_Error( 'invalid_format', __( 'Invalid cookie format.' ) );
       
   153 		}
       
   154 
       
   155 		return $parts;
       
   156 	}
       
   157 
       
   158 	/**
       
   159 	 * Generates the recovery mode cookie value.
       
   160 	 *
       
   161 	 * The cookie is a base64 encoded string with the following format:
       
   162 	 *
       
   163 	 * recovery_mode|iat|rand|signature
       
   164 	 *
       
   165 	 * Where "recovery_mode" is a constant string,
       
   166 	 * iat is the time the cookie was generated at,
       
   167 	 * rand is a randomly generated password that is also used as a session identifier
       
   168 	 * and signature is an hmac of the preceding 3 parts.
       
   169 	 *
       
   170 	 * @since 5.2.0
       
   171 	 *
       
   172 	 * @return string Generated cookie content.
       
   173 	 */
       
   174 	private function generate_cookie() {
       
   175 		$to_sign = sprintf( 'recovery_mode|%s|%s', time(), wp_generate_password( 20, false ) );
       
   176 		$signed  = $this->recovery_mode_hash( $to_sign );
       
   177 
       
   178 		return base64_encode( sprintf( '%s|%s', $to_sign, $signed ) );
       
   179 	}
       
   180 
       
   181 	/**
       
   182 	 * Gets a form of `wp_hash()` specific to Recovery Mode.
       
   183 	 *
       
   184 	 * We cannot use `wp_hash()` because it is defined in `pluggable.php` which is not loaded until after plugins are loaded,
       
   185 	 * which is too late to verify the recovery mode cookie.
       
   186 	 *
       
   187 	 * This tries to use the `AUTH` salts first, but if they aren't valid specific salts will be generated and stored.
       
   188 	 *
       
   189 	 * @since 5.2.0
       
   190 	 *
       
   191 	 * @param string $data Data to hash.
       
   192 	 * @return string|false The hashed $data, or false on failure.
       
   193 	 */
       
   194 	private function recovery_mode_hash( $data ) {
       
   195 		if ( ! defined( 'AUTH_KEY' ) || AUTH_KEY === 'put your unique phrase here' ) {
       
   196 			$auth_key = get_site_option( 'recovery_mode_auth_key' );
       
   197 
       
   198 			if ( ! $auth_key ) {
       
   199 				if ( ! function_exists( 'wp_generate_password' ) ) {
       
   200 					require_once ABSPATH . WPINC . '/pluggable.php';
       
   201 				}
       
   202 
       
   203 				$auth_key = wp_generate_password( 64, true, true );
       
   204 				update_site_option( 'recovery_mode_auth_key', $auth_key );
       
   205 			}
       
   206 		} else {
       
   207 			$auth_key = AUTH_KEY;
       
   208 		}
       
   209 
       
   210 		if ( ! defined( 'AUTH_SALT' ) || AUTH_SALT === 'put your unique phrase here' || AUTH_SALT === $auth_key ) {
       
   211 			$auth_salt = get_site_option( 'recovery_mode_auth_salt' );
       
   212 
       
   213 			if ( ! $auth_salt ) {
       
   214 				if ( ! function_exists( 'wp_generate_password' ) ) {
       
   215 					require_once ABSPATH . WPINC . '/pluggable.php';
       
   216 				}
       
   217 
       
   218 				$auth_salt = wp_generate_password( 64, true, true );
       
   219 				update_site_option( 'recovery_mode_auth_salt', $auth_salt );
       
   220 			}
       
   221 		} else {
       
   222 			$auth_salt = AUTH_SALT;
       
   223 		}
       
   224 
       
   225 		$secret = $auth_key . $auth_salt;
       
   226 
       
   227 		return hash_hmac( 'sha1', $data, $secret );
       
   228 	}
       
   229 }