3 * Session storage in object cache.
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License along
16 * with this program; if not, write to the Free Software Foundation, Inc.,
17 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
18 * http://www.gnu.org/copyleft/gpl.html
24 namespace MediaWiki\Session
;
26 use MediaWiki\MainConfigNames
;
27 use MediaWiki\MediaWikiServices
;
28 use Psr\Log\LoggerInterface
;
29 use Psr\Log\NullLogger
;
30 use SessionHandlerInterface
;
31 use Wikimedia\AtEase\AtEase
;
32 use Wikimedia\ObjectCache\BagOStuff
;
33 use Wikimedia\PhpSessionSerializer
;
36 * Adapter for PHP's session handling
40 class PHPSessionHandler
implements SessionHandlerInterface
{
41 /** @var PHPSessionHandler */
42 protected static $instance = null;
44 /** @var bool Whether PHP session handling is enabled */
45 protected $enable = false;
48 protected $warn = true;
50 protected ?SessionManagerInterface
$manager = null;
51 protected ?BagOStuff
$store = null;
52 protected LoggerInterface
$logger;
54 /** @var array Track original session fields for later modification check */
55 protected $sessionFieldCache = [];
57 protected function __construct( SessionManager
$manager ) {
58 $this->setEnableFlags(
59 MediaWikiServices
::getInstance()->getMainConfig()->get( MainConfigNames
::PHPSessionHandling
)
61 $manager->setupPHPSessionHandler( $this );
65 * Set $this->enable and $this->warn
67 * Separate just because there doesn't seem to be a good way to test it
70 * @param string $PHPSessionHandling See $wgPHPSessionHandling
72 private function setEnableFlags( $PHPSessionHandling ) {
73 switch ( $PHPSessionHandling ) {
85 $this->enable
= false;
92 * Test whether the handler is installed
95 public static function isInstalled() {
96 return (bool)self
::$instance;
100 * Test whether the handler is installed and enabled
103 public static function isEnabled() {
104 return self
::$instance && self
::$instance->enable
;
108 * Install a session handler for the current web request
109 * @param SessionManager $manager
111 public static function install( SessionManager
$manager ) {
112 if ( self
::$instance ) {
113 $manager->setupPHPSessionHandler( self
::$instance );
117 // @codeCoverageIgnoreStart
118 if ( defined( 'MW_NO_SESSION_HANDLER' ) ) {
119 throw new \
BadMethodCallException( 'MW_NO_SESSION_HANDLER is defined' );
121 // @codeCoverageIgnoreEnd
123 self
::$instance = new self( $manager );
125 // Close any auto-started session, before we replace it
126 session_write_close();
129 AtEase
::suppressWarnings();
131 // Tell PHP not to mess with cookies itself
132 ini_set( 'session.use_cookies', 0 );
133 ini_set( 'session.use_trans_sid', 0 );
135 // T124510: Disable automatic PHP session related cache headers.
136 // MediaWiki adds its own headers and the default PHP behavior may
137 // set headers such as 'Pragma: no-cache' that cause problems with
139 session_cache_limiter( '' );
141 // Also set a serialization handler
142 PhpSessionSerializer
::setSerializeHandler();
144 // Register this as the save handler, and register an appropriate
145 // shutdown function.
146 session_set_save_handler( self
::$instance, true );
148 AtEase
::restoreWarnings();
153 * Set the manager, store, and logger
154 * @internal Use self::install().
155 * @param SessionManagerInterface $manager
156 * @param BagOStuff $store
157 * @param LoggerInterface $logger
159 public function setManager(
160 SessionManagerInterface
$manager, BagOStuff
$store, LoggerInterface
$logger
162 if ( $this->manager
!== $manager ) {
163 // Close any existing session before we change stores
164 if ( $this->manager
) {
165 session_write_close();
167 $this->manager
= $manager;
168 $this->store
= $store;
169 $this->logger
= $logger;
170 PhpSessionSerializer
::setLogger( $this->logger
);
175 * Initialize the session (handler)
176 * @internal For internal use only
177 * @param string $save_path Path used to store session files (ignored)
178 * @param string $session_name Session name (ignored)
181 #[\ReturnTypeWillChange]
182 public function open( $save_path, $session_name ) {
183 if ( self
::$instance !== $this ) {
184 throw new \
UnexpectedValueException( __METHOD__
. ': Wrong instance called!' );
186 if ( !$this->enable
) {
187 throw new \
BadMethodCallException( 'Attempt to use PHP session management' );
193 * Close the session (handler)
194 * @internal For internal use only
197 #[\ReturnTypeWillChange]
198 public function close() {
199 if ( self
::$instance !== $this ) {
200 throw new \
UnexpectedValueException( __METHOD__
. ': Wrong instance called!' );
202 $this->sessionFieldCache
= [];
208 * @internal For internal use only
209 * @param string $id Session id
210 * @return string Session data
212 #[\ReturnTypeWillChange]
213 public function read( $id ) {
214 if ( self
::$instance !== $this ) {
215 throw new \
UnexpectedValueException( __METHOD__
. ': Wrong instance called!' );
217 if ( !$this->enable
) {
218 throw new \
BadMethodCallException( 'Attempt to use PHP session management' );
221 $session = $this->manager
->getSessionById( $id, false );
227 $data = iterator_to_array( $session );
228 $this->sessionFieldCache
[$id] = $data;
229 return (string)PhpSessionSerializer
::encode( $data );
234 * @internal For internal use only
235 * @param string $id Session id
236 * @param string $dataStr Session data. Not that you should ever call this
237 * directly, but note that this has the same issues with code injection
238 * via user-controlled data as does PHP's unserialize function.
241 #[\ReturnTypeWillChange]
242 public function write( $id, $dataStr ) {
243 if ( self
::$instance !== $this ) {
244 throw new \
UnexpectedValueException( __METHOD__
. ': Wrong instance called!' );
246 if ( !$this->enable
) {
247 throw new \
BadMethodCallException( 'Attempt to use PHP session management' );
250 $session = $this->manager
->getSessionById( $id, true );
252 // This can happen under normal circumstances, if the session exists but is
253 // invalid. Let's emit a log warning instead of a PHP warning.
254 $this->logger
->warning(
255 __METHOD__
. ': Session "{session}" cannot be loaded, skipping write.',
262 // First, decode the string PHP handed us
263 $data = PhpSessionSerializer
::decode( $dataStr );
264 if ( $data === null ) {
265 // @codeCoverageIgnoreStart
267 // @codeCoverageIgnoreEnd
270 // Now merge the data into the Session object.
272 $cache = $this->sessionFieldCache
[$id] ??
[];
273 foreach ( $data as $key => $value ) {
274 if ( !array_key_exists( $key, $cache ) ) {
275 if ( $session->exists( $key ) ) {
276 // New in both, so ignore and log
277 $this->logger
->warning(
278 __METHOD__
. ": Key \"$key\" added in both Session and \$_SESSION!"
281 // New in $_SESSION, keep it
282 $session->set( $key, $value );
285 } elseif ( $cache[$key] === $value ) {
286 // Unchanged in $_SESSION, so ignore it
287 } elseif ( !$session->exists( $key ) ) {
288 // Deleted in Session, keep but log
289 $this->logger
->warning(
290 __METHOD__
. ": Key \"$key\" deleted in Session and changed in \$_SESSION!"
292 $session->set( $key, $value );
294 } elseif ( $cache[$key] === $session->get( $key ) ) {
295 // Unchanged in Session, so keep it
296 $session->set( $key, $value );
299 // Changed in both, so ignore and log
300 $this->logger
->warning(
301 __METHOD__
. ": Key \"$key\" changed in both Session and \$_SESSION!"
305 // Anything deleted in $_SESSION and unchanged in Session should be deleted too
306 // (but not if $_SESSION can't represent it at all)
307 PhpSessionSerializer
::setLogger( new NullLogger() );
308 foreach ( $cache as $key => $value ) {
309 if ( !array_key_exists( $key, $data ) && $session->exists( $key ) &&
310 PhpSessionSerializer
::encode( [ $key => true ] )
312 if ( $value === $session->get( $key ) ) {
313 // Unchanged in Session, delete it
314 $session->remove( $key );
317 // Changed in Session, ignore deletion and log
318 $this->logger
->warning(
319 __METHOD__
. ": Key \"$key\" changed in Session and deleted in \$_SESSION!"
324 PhpSessionSerializer
::setLogger( $this->logger
);
326 // Save and update cache if anything changed
329 wfDeprecated( '$_SESSION', '1.27' );
330 $this->logger
->warning( 'Something wrote to $_SESSION!' );
334 $this->sessionFieldCache
[$id] = iterator_to_array( $session );
344 * @internal For internal use only
345 * @param string $id Session id
348 #[\ReturnTypeWillChange]
349 public function destroy( $id ) {
350 if ( self
::$instance !== $this ) {
351 throw new \
UnexpectedValueException( __METHOD__
. ': Wrong instance called!' );
353 if ( !$this->enable
) {
354 throw new \
BadMethodCallException( 'Attempt to use PHP session management' );
356 $session = $this->manager
->getSessionById( $id, false );
364 * Execute garbage collection.
365 * @internal For internal use only
366 * @param int $maxlifetime Maximum session life time (ignored)
368 * @codeCoverageIgnore See T135576
370 #[\ReturnTypeWillChange]
371 public function gc( $maxlifetime ) {
372 if ( self
::$instance !== $this ) {
373 throw new \
UnexpectedValueException( __METHOD__
. ': Wrong instance called!' );
375 $this->store
->deleteObjectsExpiringBefore( wfTimestampNow() );