class-recursive-arrayaccess.php
5 years ago
class-wp-session.php
5 years ago
wp-session.php
5 years ago
class-wp-session.php
332 lines
| 1 | <?php |
| 2 | /** |
| 3 | * WordPress session management. |
| 4 | * |
| 5 | * Standardizes WordPress session data using database-backed options for storage. |
| 6 | * for storing user session information. |
| 7 | * |
| 8 | * @package WordPress |
| 9 | * @subpackage Session |
| 10 | * @since 3.7.0 |
| 11 | */ |
| 12 | |
| 13 | // Exit if accessed directly |
| 14 | if ( ! defined( 'ABSPATH' ) ) exit; |
| 15 | |
| 16 | /** |
| 17 | * WordPress Session class for managing user session data. |
| 18 | * |
| 19 | * @package WordPress |
| 20 | * @since 3.7.0 |
| 21 | */ |
| 22 | final class WP_Session extends Recursive_ArrayAccess implements Iterator, Countable { |
| 23 | /** |
| 24 | * ID of the current session. |
| 25 | * |
| 26 | * @var string |
| 27 | */ |
| 28 | public $session_id; |
| 29 | |
| 30 | /** |
| 31 | * Unix timestamp when session expires. |
| 32 | * |
| 33 | * @var int |
| 34 | */ |
| 35 | protected $expires; |
| 36 | |
| 37 | /** |
| 38 | * Unix timestamp indicating when the expiration time needs to be reset. |
| 39 | * |
| 40 | * @var int |
| 41 | */ |
| 42 | protected $exp_variant; |
| 43 | |
| 44 | /** |
| 45 | * Singleton instance. |
| 46 | * |
| 47 | * @var bool|WP_Session |
| 48 | */ |
| 49 | private static $instance = false; |
| 50 | |
| 51 | /** |
| 52 | * Retrieve the current session instance. |
| 53 | * |
| 54 | * @param bool $session_id Session ID from which to populate data. |
| 55 | * |
| 56 | * @return bool|WP_Session |
| 57 | */ |
| 58 | public static function get_instance() { |
| 59 | if ( ! self::$instance ) { |
| 60 | self::$instance = new self(); |
| 61 | } |
| 62 | |
| 63 | return self::$instance; |
| 64 | } |
| 65 | |
| 66 | /** |
| 67 | * Default constructor. |
| 68 | * Will rebuild the session collection from the given session ID if it exists. Otherwise, will |
| 69 | * create a new session with that ID. |
| 70 | * |
| 71 | * @param $session_id |
| 72 | * @uses apply_filters Calls `wp_session_expiration` to determine how long until sessions expire. |
| 73 | */ |
| 74 | protected function __construct() { |
| 75 | if ( isset( $_COOKIE[WP_SESSION_COOKIE] ) ) { |
| 76 | $cookie = stripslashes( $_COOKIE[WP_SESSION_COOKIE] ); |
| 77 | $cookie_crumbs = explode( '||', $cookie ); |
| 78 | |
| 79 | if( $this->is_valid_md5( $cookie_crumbs[0] ) ) { |
| 80 | |
| 81 | $this->session_id = $cookie_crumbs[0]; |
| 82 | |
| 83 | } else { |
| 84 | |
| 85 | $this->regenerate_id( true ); |
| 86 | |
| 87 | } |
| 88 | |
| 89 | $this->expires = $cookie_crumbs[1]; |
| 90 | $this->exp_variant = $cookie_crumbs[2]; |
| 91 | |
| 92 | // Update the session expiration if we're past the variant time |
| 93 | if ( time() > $this->exp_variant ) { |
| 94 | $this->set_expiration(); |
| 95 | delete_option( "_wp_session_expires_{$this->session_id}" ); |
| 96 | add_option( "_wp_session_expires_{$this->session_id}", $this->expires, '', 'no' ); |
| 97 | } |
| 98 | } else { |
| 99 | $this->session_id = $this->generate_id(); |
| 100 | $this->set_expiration(); |
| 101 | } |
| 102 | |
| 103 | $this->read_data(); |
| 104 | |
| 105 | $this->set_cookie(); |
| 106 | } |
| 107 | |
| 108 | /** |
| 109 | * Set both the expiration time and the expiration variant. |
| 110 | * |
| 111 | * If the current time is below the variant, we don't update the session's expiration time. If it's |
| 112 | * greater than the variant, then we update the expiration time in the database. This prevents |
| 113 | * writing to the database on every page load for active sessions and only updates the expiration |
| 114 | * time if we're nearing when the session actually expires. |
| 115 | * |
| 116 | * By default, the expiration time is set to 30 minutes. |
| 117 | * By default, the expiration variant is set to 24 minutes. |
| 118 | * |
| 119 | * As a result, the session expiration time - at a maximum - will only be written to the database once |
| 120 | * every 24 minutes. After 30 minutes, the session will have been expired. No cookie will be sent by |
| 121 | * the browser, and the old session will be queued for deletion by the garbage collector. |
| 122 | * |
| 123 | * @uses apply_filters Calls `wp_session_expiration_variant` to get the max update window for session data. |
| 124 | * @uses apply_filters Calls `wp_session_expiration` to get the standard expiration time for sessions. |
| 125 | */ |
| 126 | protected function set_expiration() { |
| 127 | $this->exp_variant = time() + (int) apply_filters( 'wp_session_expiration_variant', 24 * 60 ); |
| 128 | $this->expires = time() + (int) apply_filters( 'wp_session_expiration', 30 * 60 ); |
| 129 | } |
| 130 | |
| 131 | /** |
| 132 | * Set the session cookie |
| 133 | */ |
| 134 | protected function set_cookie() { |
| 135 | @setcookie( WP_SESSION_COOKIE, $this->session_id . '||' . $this->expires . '||' . $this->exp_variant , $this->expires, COOKIEPATH, COOKIE_DOMAIN ); |
| 136 | } |
| 137 | |
| 138 | /** |
| 139 | * Generate a cryptographically strong unique ID for the session token. |
| 140 | * |
| 141 | * @return string |
| 142 | */ |
| 143 | protected function generate_id() { |
| 144 | require_once( ABSPATH . 'wp-includes/class-phpass.php'); |
| 145 | $hasher = new PasswordHash( 8, false ); |
| 146 | |
| 147 | return md5( $hasher->get_random_bytes( 32 ) ); |
| 148 | } |
| 149 | |
| 150 | /** |
| 151 | * Checks if is valid md5 string |
| 152 | * |
| 153 | * @param string $md5 |
| 154 | * @return int |
| 155 | */ |
| 156 | protected function is_valid_md5( $md5 = '' ){ |
| 157 | return preg_match( '/^[a-f0-9]{32}$/', $md5 ); |
| 158 | } |
| 159 | |
| 160 | /** |
| 161 | * Read data from a transient for the current session. |
| 162 | * |
| 163 | * Automatically resets the expiration time for the session transient to some time in the future. |
| 164 | * |
| 165 | * @return array |
| 166 | */ |
| 167 | protected function read_data() { |
| 168 | $this->container = get_option( "_wp_session_{$this->session_id}", array() ); |
| 169 | |
| 170 | return $this->container; |
| 171 | } |
| 172 | |
| 173 | /** |
| 174 | * Write the data from the current session to the data storage system. |
| 175 | */ |
| 176 | public function write_data() { |
| 177 | $option_key = "_wp_session_{$this->session_id}"; |
| 178 | |
| 179 | // Only write the collection to the DB if it's changed. |
| 180 | if ( $this->dirty ) { |
| 181 | if ( false === get_option( $option_key ) ) { |
| 182 | add_option( "_wp_session_{$this->session_id}", $this->container, '', 'no' ); |
| 183 | add_option( "_wp_session_expires_{$this->session_id}", $this->expires, '', 'no' ); |
| 184 | } else { |
| 185 | delete_option( "_wp_session_{$this->session_id}" ); |
| 186 | add_option( "_wp_session_{$this->session_id}", $this->container, '', 'no' ); |
| 187 | } |
| 188 | } |
| 189 | } |
| 190 | |
| 191 | /** |
| 192 | * Output the current container contents as a JSON-encoded string. |
| 193 | * |
| 194 | * @return string |
| 195 | */ |
| 196 | public function json_out() { |
| 197 | return json_encode( $this->container ); |
| 198 | } |
| 199 | |
| 200 | /** |
| 201 | * Decodes a JSON string and, if the object is an array, overwrites the session container with its contents. |
| 202 | * |
| 203 | * @param string $data |
| 204 | * |
| 205 | * @return bool |
| 206 | */ |
| 207 | public function json_in( $data ) { |
| 208 | $array = json_decode( $data ); |
| 209 | |
| 210 | if ( is_array( $array ) ) { |
| 211 | $this->container = $array; |
| 212 | return true; |
| 213 | } |
| 214 | |
| 215 | return false; |
| 216 | } |
| 217 | |
| 218 | /** |
| 219 | * Regenerate the current session's ID. |
| 220 | * |
| 221 | * @param bool $delete_old Flag whether or not to delete the old session data from the server. |
| 222 | */ |
| 223 | public function regenerate_id( $delete_old = false ) { |
| 224 | if ( $delete_old ) { |
| 225 | delete_option( "_wp_session_{$this->session_id}" ); |
| 226 | } |
| 227 | |
| 228 | $this->session_id = $this->generate_id(); |
| 229 | |
| 230 | $this->set_cookie(); |
| 231 | } |
| 232 | |
| 233 | /** |
| 234 | * Check if a session has been initialized. |
| 235 | * |
| 236 | * @return bool |
| 237 | */ |
| 238 | public function session_started() { |
| 239 | return !!self::$instance; |
| 240 | } |
| 241 | |
| 242 | /** |
| 243 | * Return the read-only cache expiration value. |
| 244 | * |
| 245 | * @return int |
| 246 | */ |
| 247 | public function cache_expiration() { |
| 248 | return $this->expires; |
| 249 | } |
| 250 | |
| 251 | /** |
| 252 | * Flushes all session variables. |
| 253 | */ |
| 254 | public function reset() { |
| 255 | $this->container = array(); |
| 256 | } |
| 257 | |
| 258 | /*****************************************************************/ |
| 259 | /* Iterator Implementation */ |
| 260 | /*****************************************************************/ |
| 261 | |
| 262 | /** |
| 263 | * Current position of the array. |
| 264 | * |
| 265 | * @link http://php.net/manual/en/iterator.current.php |
| 266 | * |
| 267 | * @return mixed |
| 268 | */ |
| 269 | public function current() { |
| 270 | return current( $this->container ); |
| 271 | } |
| 272 | |
| 273 | /** |
| 274 | * Key of the current element. |
| 275 | * |
| 276 | * @link http://php.net/manual/en/iterator.key.php |
| 277 | * |
| 278 | * @return mixed |
| 279 | */ |
| 280 | public function key() { |
| 281 | return key( $this->container ); |
| 282 | } |
| 283 | |
| 284 | /** |
| 285 | * Move the internal point of the container array to the next item |
| 286 | * |
| 287 | * @link http://php.net/manual/en/iterator.next.php |
| 288 | * |
| 289 | * @return void |
| 290 | */ |
| 291 | public function next() { |
| 292 | next( $this->container ); |
| 293 | } |
| 294 | |
| 295 | /** |
| 296 | * Rewind the internal point of the container array. |
| 297 | * |
| 298 | * @link http://php.net/manual/en/iterator.rewind.php |
| 299 | * |
| 300 | * @return void |
| 301 | */ |
| 302 | public function rewind() { |
| 303 | reset( $this->container ); |
| 304 | } |
| 305 | |
| 306 | /** |
| 307 | * Is the current key valid? |
| 308 | * |
| 309 | * @link http://php.net/manual/en/iterator.rewind.php |
| 310 | * |
| 311 | * @return bool |
| 312 | */ |
| 313 | public function valid() { |
| 314 | return $this->offsetExists( $this->key() ); |
| 315 | } |
| 316 | |
| 317 | /*****************************************************************/ |
| 318 | /* Countable Implementation */ |
| 319 | /*****************************************************************/ |
| 320 | |
| 321 | /** |
| 322 | * Get the count of elements in the container array. |
| 323 | * |
| 324 | * @link http://php.net/manual/en/countable.count.php |
| 325 | * |
| 326 | * @return int |
| 327 | */ |
| 328 | public function count() { |
| 329 | return count( $this->container ); |
| 330 | } |
| 331 | } |
| 332 |