includes/session/SessionManager.php

   1 <?php
   2 /**
   3  * MediaWiki\Session entry point
   4  *
   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.
   9  *
  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.
  14  *
  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
  19  *
  20  * @file
  21  * @ingroup Session
  22  */
  23
  24 namespace MediaWiki\Session;
  25
  26 use MWException;
  27 use Psr\Log\LoggerInterface;
  28 use BagOStuff;
  29 use CachedBagOStuff;
  30 use Config;
  31 use FauxRequest;
  32 use User;
  33 use WebRequest;
  34
  35 /**
  36  * This serves as the entry point to the MediaWiki session handling system.
  37  *
  38  * @ingroup Session
  39  * @since 1.27
  40  */
  41 final class SessionManager implements SessionManagerInterface {
  42         /** @var SessionManager|null */
  43         private static $instance = null;
  44
  45         /** @var Session|null */
  46         private static $globalSession = null;
  47
  48         /** @var WebRequest|null */
  49         private static $globalSessionRequest = null;
  50
  51         /** @var LoggerInterface */
  52         private $logger;
  53
  54         /** @var Config */
  55         private $config;
  56
  57         /** @var CachedBagOStuff|null */
  58         private $store;
  59
  60         /** @var SessionProvider[] */
  61         private $sessionProviders = null;
  62
  63         /** @var string[] */
  64         private $varyCookies = null;
  65
  66         /** @var array */
  67         private $varyHeaders = null;
  68
  69         /** @var SessionBackend[] */
  70         private $allSessionBackends = [];
  71
  72         /** @var SessionId[] */
  73         private $allSessionIds = [];
  74
  75         /** @var string[] */
  76         private $preventUsers = [];
  77
  78         /**
  79          * Get the global SessionManager
  80          * @return SessionManagerInterface
  81          *  (really a SessionManager, but this is to make IDEs less confused)
  82          */
  83         public static function singleton() {
  84                 if ( self::$instance === null ) {
  85                         self::$instance = new self();
  86                 }
  87                 return self::$instance;
  88         }
  89
  90         /**
  91          * Get the "global" session
  92          *
  93          * If PHP's session_id() has been set, returns that session. Otherwise
  94          * returns the session for RequestContext::getMain()->getRequest().
  95          *
  96          * @return Session
  97          */
  98         public static function getGlobalSession() {
  99                 if ( !PHPSessionHandler::isEnabled() ) {
 100                         $id = '';
 101                 } else {
 102                         $id = session_id();
 103                 }
 104
 105                 $request = \RequestContext::getMain()->getRequest();
 106                 if (
 107                         !self::$globalSession // No global session is set up yet
 108                         || self::$globalSessionRequest !== $request // The global WebRequest changed
 109                         || $id !== '' && self::$globalSession->getId() !== $id // Someone messed with session_id()
 110                 ) {
 111                         self::$globalSessionRequest = $request;
 112                         if ( $id === '' ) {
 113                                 // session_id() wasn't used, so fetch the Session from the WebRequest.
 114                                 // We use $request->getSession() instead of $singleton->getSessionForRequest()
 115                                 // because doing the latter would require a public
 116                                 // "$request->getSessionId()" method that would confuse end
 117                                 // users by returning SessionId|null where they'd expect it to
 118                                 // be short for $request->getSession()->getId(), and would
 119                                 // wind up being a duplicate of the code in
 120                                 // $request->getSession() anyway.
 121                                 self::$globalSession = $request->getSession();
 122                         } else {
 123                                 // Someone used session_id(), so we need to follow suit.
 124                                 // Note this overwrites whatever session might already be
 125                                 // associated with $request with the one for $id.
 126                                 self::$globalSession = self::singleton()->getSessionById( $id, true, $request )
 127                                         ?: $request->getSession();
 128                         }
 129                 }
 130                 return self::$globalSession;
 131         }
 132
 133         /**
 134          * @param array $options
 135          *  - config: Config to fetch configuration from. Defaults to the default 'main' config.
 136          *  - logger: LoggerInterface to use for logging. Defaults to the 'session' channel.
 137          *  - store: BagOStuff to store session data in.
 138          */
 139         public function __construct( $options = [] ) {
 140                 if ( isset( $options['config'] ) ) {
 141                         $this->config = $options['config'];
 142                         if ( !$this->config instanceof Config ) {
 143                                 throw new \InvalidArgumentException(
 144                                         '$options[\'config\'] must be an instance of Config'
 145                                 );
 146                         }
 147                 } else {
 148                         $this->config = \ConfigFactory::getDefaultInstance()->makeConfig( 'main' );
 149                 }
 150
 151                 if ( isset( $options['logger'] ) ) {
 152                         if ( !$options['logger'] instanceof LoggerInterface ) {
 153                                 throw new \InvalidArgumentException(
 154                                         '$options[\'logger\'] must be an instance of LoggerInterface'
 155                                 );
 156                         }
 157                         $this->setLogger( $options['logger'] );
 158                 } else {
 159                         $this->setLogger( \MediaWiki\Logger\LoggerFactory::getInstance( 'session' ) );
 160                 }
 161
 162                 if ( isset( $options['store'] ) ) {
 163                         if ( !$options['store'] instanceof BagOStuff ) {
 164                                 throw new \InvalidArgumentException(
 165                                         '$options[\'store\'] must be an instance of BagOStuff'
 166                                 );
 167                         }
 168                         $store = $options['store'];
 169                 } else {
 170                         $store = \ObjectCache::getInstance( $this->config->get( 'SessionCacheType' ) );
 171                 }
 172                 $this->store = $store instanceof CachedBagOStuff ? $store : new CachedBagOStuff( $store );
 173
 174                 register_shutdown_function( [ $this, 'shutdown' ] );
 175         }
 176
 177         public function setLogger( LoggerInterface $logger ) {
 178                 $this->logger = $logger;
 179         }
 180
 181         public function getSessionForRequest( WebRequest $request ) {
 182                 $info = $this->getSessionInfoForRequest( $request );
 183
 184                 if ( !$info ) {
 185                         $session = $this->getEmptySession( $request );
 186                 } else {
 187                         $session = $this->getSessionFromInfo( $info, $request );
 188                 }
 189                 return $session;
 190         }
 191
 192         public function getSessionById( $id, $create = false, WebRequest $request = null ) {
 193                 if ( !self::validateSessionId( $id ) ) {
 194                         throw new \InvalidArgumentException( 'Invalid session ID' );
 195                 }
 196                 if ( !$request ) {
 197                         $request = new FauxRequest;
 198                 }
 199
 200                 $session = null;
 201                 $info = new SessionInfo( SessionInfo::MIN_PRIORITY, [ 'id' => $id, 'idIsSafe' => true ] );
 202
 203                 // If we already have the backend loaded, use it directly
 204                 if ( isset( $this->allSessionBackends[$id] ) ) {
 205                         return $this->getSessionFromInfo( $info, $request );
 206                 }
 207
 208                 // Test if the session is in storage, and if so try to load it.
 209                 $key = wfMemcKey( 'MWSession', $id );
 210                 if ( is_array( $this->store->get( $key ) ) ) {
 211                         $create = false; // If loading fails, don't bother creating because it probably will fail too.
 212                         if ( $this->loadSessionInfoFromStore( $info, $request ) ) {
 213                                 $session = $this->getSessionFromInfo( $info, $request );
 214                         }
 215                 }
 216
 217                 if ( $create && $session === null ) {
 218                         $ex = null;
 219                         try {
 220                                 $session = $this->getEmptySessionInternal( $request, $id );
 221                         } catch ( \Exception $ex ) {
 222                                 $this->logger->error( 'Failed to create empty session: {exception}',
 223                                         [
 224                                                 'method' => __METHOD__,
 225                                                 'exception' => $ex,
 226                                 ] );
 227                                 $session = null;
 228                         }
 229                 }
 230
 231                 return $session;
 232         }
 233
 234         public function getEmptySession( WebRequest $request = null ) {
 235                 return $this->getEmptySessionInternal( $request );
 236         }
 237
 238         /**
 239          * @see SessionManagerInterface::getEmptySession
 240          * @param WebRequest|null $request
 241          * @param string|null $id ID to force on the new session
 242          * @return Session
 243          */
 244         private function getEmptySessionInternal( WebRequest $request = null, $id = null ) {
 245                 if ( $id !== null ) {
 246                         if ( !self::validateSessionId( $id ) ) {
 247                                 throw new \InvalidArgumentException( 'Invalid session ID' );
 248                         }
 249
 250                         $key = wfMemcKey( 'MWSession', $id );
 251                         if ( is_array( $this->store->get( $key ) ) ) {
 252                                 throw new \InvalidArgumentException( 'Session ID already exists' );
 253                         }
 254                 }
 255                 if ( !$request ) {
 256                         $request = new FauxRequest;
 257                 }
 258
 259                 $infos = [];
 260                 foreach ( $this->getProviders() as $provider ) {
 261                         $info = $provider->newSessionInfo( $id );
 262                         if ( !$info ) {
 263                                 continue;
 264                         }
 265                         if ( $info->getProvider() !== $provider ) {
 266                                 throw new \UnexpectedValueException(
 267                                         "$provider returned an empty session info for a different provider: $info"
 268                                 );
 269                         }
 270                         if ( $id !== null && $info->getId() !== $id ) {
 271                                 throw new \UnexpectedValueException(
 272                                         "$provider returned empty session info with a wrong id: " .
 273                                                 $info->getId() . ' != ' . $id
 274                                 );
 275                         }
 276                         if ( !$info->isIdSafe() ) {
 277                                 throw new \UnexpectedValueException(
 278                                         "$provider returned empty session info with id flagged unsafe"
 279                                 );
 280                         }
 281                         $compare = $infos ? SessionInfo::compare( $infos[0], $info ) : -1;
 282                         if ( $compare > 0 ) {
 283                                 continue;
 284                         }
 285                         if ( $compare === 0 ) {
 286                                 $infos[] = $info;
 287                         } else {
 288                                 $infos = [ $info ];
 289                         }
 290                 }
 291
 292                 // Make sure there's exactly one
 293                 if ( count( $infos ) > 1 ) {
 294                         throw new \UnexpectedValueException(
 295                                 'Multiple empty sessions tied for top priority: ' . implode( ', ', $infos )
 296                         );
 297                 } elseif ( count( $infos ) < 1 ) {
 298                         throw new \UnexpectedValueException( 'No provider could provide an empty session!' );
 299                 }
 300
 301                 return $this->getSessionFromInfo( $infos[0], $request );
 302         }
 303
 304         public function invalidateSessionsForUser( User $user ) {
 305                 $user->setToken();
 306                 $user->saveSettings();
 307
 308                 $authUser = \MediaWiki\Auth\AuthManager::callLegacyAuthPlugin( 'getUserInstance', [ &$user ] );
 309                 if ( $authUser ) {
 310                         $authUser->resetAuthToken();
 311                 }
 312
 313                 foreach ( $this->getProviders() as $provider ) {
 314                         $provider->invalidateSessionsForUser( $user );
 315                 }
 316         }
 317
 318         public function getVaryHeaders() {
 319                 // @codeCoverageIgnoreStart
 320                 if ( defined( 'MW_NO_SESSION' ) && MW_NO_SESSION !== 'warn' ) {
 321                         return [];
 322                 }
 323                 // @codeCoverageIgnoreEnd
 324                 if ( $this->varyHeaders === null ) {
 325                         $headers = [];
 326                         foreach ( $this->getProviders() as $provider ) {
 327                                 foreach ( $provider->getVaryHeaders() as $header => $options ) {
 328                                         if ( !isset( $headers[$header] ) ) {
 329                                                 $headers[$header] = [];
 330                                         }
 331                                         if ( is_array( $options ) ) {
 332                                                 $headers[$header] = array_unique( array_merge( $headers[$header], $options ) );
 333                                         }
 334                                 }
 335                         }
 336                         $this->varyHeaders = $headers;
 337                 }
 338                 return $this->varyHeaders;
 339         }
 340
 341         public function getVaryCookies() {
 342                 // @codeCoverageIgnoreStart
 343                 if ( defined( 'MW_NO_SESSION' ) && MW_NO_SESSION !== 'warn' ) {
 344                         return [];
 345                 }
 346                 // @codeCoverageIgnoreEnd
 347                 if ( $this->varyCookies === null ) {
 348                         $cookies = [];
 349                         foreach ( $this->getProviders() as $provider ) {
 350                                 $cookies = array_merge( $cookies, $provider->getVaryCookies() );
 351                         }
 352                         $this->varyCookies = array_values( array_unique( $cookies ) );
 353                 }
 354                 return $this->varyCookies;
 355         }
 356
 357         /**
 358          * Validate a session ID
 359          * @param string $id
 360          * @return bool
 361          */
 362         public static function validateSessionId( $id ) {
 363                 return is_string( $id ) && preg_match( '/^[a-zA-Z0-9_-]{32,}$/', $id );
 364         }
 365
 366         /**
 367          * @name Internal methods
 368          * @{
 369          */
 370
 371         /**
 372          * Auto-create the given user, if necessary
 373          * @private Don't call this yourself. Let Setup.php do it for you at the right time.
 374          * @deprecated since 1.27, use MediaWiki\Auth\AuthManager::autoCreateUser instead
 375          * @param User $user User to auto-create
 376          * @return bool Success
 377          */
 378         public static function autoCreateUser( User $user ) {
 379                 global $wgAuth, $wgDisableAuthManager;
 380
 381                 // @codeCoverageIgnoreStart
 382                 if ( !$wgDisableAuthManager ) {
 383                         wfDeprecated( __METHOD__, '1.27' );
 384                         return \MediaWiki\Auth\AuthManager::singleton()->autoCreateUser(
 385                                 $user,
 386                                 \MediaWiki\Auth\AuthManager::AUTOCREATE_SOURCE_SESSION,
 387                                 false
 388                         )->isGood();
 389                 }
 390                 // @codeCoverageIgnoreEnd
 391
 392                 $logger = self::singleton()->logger;
 393
 394                 // Much of this code is based on that in CentralAuth
 395
 396                 // Try the local user from the slave DB
 397                 $localId = User::idFromName( $user->getName() );
 398                 $flags = 0;
 399
 400                 // Fetch the user ID from the master, so that we don't try to create the user
 401                 // when they already exist, due to replication lag
 402                 // @codeCoverageIgnoreStart
 403                 if ( !$localId && wfGetLB()->getReaderIndex() != 0 ) {
 404                         $localId = User::idFromName( $user->getName(), User::READ_LATEST );
 405                         $flags = User::READ_LATEST;
 406                 }
 407                 // @codeCoverageIgnoreEnd
 408
 409                 if ( $localId ) {
 410                         // User exists after all.
 411                         $user->setId( $localId );
 412                         $user->loadFromId( $flags );
 413                         return false;
 414                 }
 415
 416                 // Denied by AuthPlugin? But ignore AuthPlugin itself.
 417                 if ( get_class( $wgAuth ) !== 'AuthPlugin' && !$wgAuth->autoCreate() ) {
 418                         $logger->debug( __METHOD__ . ': denied by AuthPlugin' );
 419                         $user->setId( 0 );
 420                         $user->loadFromId();
 421                         return false;
 422                 }
 423
 424                 // Wiki is read-only?
 425                 if ( wfReadOnly() ) {
 426                         $logger->debug( __METHOD__ . ': denied by wfReadOnly()' );
 427                         $user->setId( 0 );
 428                         $user->loadFromId();
 429                         return false;
 430                 }
 431
 432                 $userName = $user->getName();
 433
 434                 // Check the session, if we tried to create this user already there's
 435                 // no point in retrying.
 436                 $session = self::getGlobalSession();
 437                 $reason = $session->get( 'MWSession::AutoCreateBlacklist' );
 438                 if ( $reason ) {
 439                         $logger->debug( __METHOD__ . ": blacklisted in session ($reason)" );
 440                         $user->setId( 0 );
 441                         $user->loadFromId();
 442                         return false;
 443                 }
 444
 445                 // Is the IP user able to create accounts?
 446                 $anon = new User;
 447                 if ( !$anon->isAllowedAny( 'createaccount', 'autocreateaccount' )
 448                         || $anon->isBlockedFromCreateAccount()
 449                 ) {
 450                         // Blacklist the user to avoid repeated DB queries subsequently
 451                         $logger->debug( __METHOD__ . ': user is blocked from this wiki, blacklisting' );
 452                         $session->set( 'MWSession::AutoCreateBlacklist', 'blocked', 600 );
 453                         $session->persist();
 454                         $user->setId( 0 );
 455                         $user->loadFromId();
 456                         return false;
 457                 }
 458
 459                 // Check for validity of username
 460                 if ( !User::isCreatableName( $userName ) ) {
 461                         $logger->debug( __METHOD__ . ': Invalid username, blacklisting' );
 462                         $session->set( 'MWSession::AutoCreateBlacklist', 'invalid username', 600 );
 463                         $session->persist();
 464                         $user->setId( 0 );
 465                         $user->loadFromId();
 466                         return false;
 467                 }
 468
 469                 // Give other extensions a chance to stop auto creation.
 470                 $user->loadDefaults( $userName );
 471                 $abortMessage = '';
 472                 if ( !\Hooks::run( 'AbortAutoAccount', [ $user, &$abortMessage ] ) ) {
 473                         // In this case we have no way to return the message to the user,
 474                         // but we can log it.
 475                         $logger->debug( __METHOD__ . ": denied by hook: $abortMessage" );
 476                         $session->set( 'MWSession::AutoCreateBlacklist', "hook aborted: $abortMessage", 600 );
 477                         $session->persist();
 478                         $user->setId( 0 );
 479                         $user->loadFromId();
 480                         return false;
 481                 }
 482
 483                 // Make sure the name has not been changed
 484                 if ( $user->getName() !== $userName ) {
 485                         $user->setId( 0 );
 486                         $user->loadFromId();
 487                         throw new \UnexpectedValueException(
 488                                 'AbortAutoAccount hook tried to change the user name'
 489                         );
 490                 }
 491
 492                 // Ignore warnings about master connections/writes...hard to avoid here
 493                 \Profiler::instance()->getTransactionProfiler()->resetExpectations();
 494
 495                 $cache = \ObjectCache::getLocalClusterInstance();
 496                 $backoffKey = wfMemcKey( 'MWSession', 'autocreate-failed', md5( $userName ) );
 497                 if ( $cache->get( $backoffKey ) ) {
 498                         $logger->debug( __METHOD__ . ': denied by prior creation attempt failures' );
 499                         $user->setId( 0 );
 500                         $user->loadFromId();
 501                         return false;
 502                 }
 503
 504                 // Checks passed, create the user...
 505                 $from = isset( $_SERVER['REQUEST_URI'] ) ? $_SERVER['REQUEST_URI'] : 'CLI';
 506                 $logger->info( __METHOD__ . ': creating new user ({username}) - from: {url}',
 507                         [
 508                                 'username' => $userName,
 509                                 'url' => $from,
 510                 ] );
 511
 512                 try {
 513                         // Insert the user into the local DB master
 514                         $status = $user->addToDatabase();
 515                         if ( !$status->isOK() ) {
 516                                 // @codeCoverageIgnoreStart
 517                                 // double-check for a race condition (T70012)
 518                                 $id = User::idFromName( $user->getName(), User::READ_LATEST );
 519                                 if ( $id ) {
 520                                         $logger->info( __METHOD__ . ': tried to autocreate existing user',
 521                                                 [
 522                                                         'username' => $userName,
 523                                                 ] );
 524                                 } else {
 525                                         $logger->error(
 526                                                 __METHOD__ . ': failed with message ' . $status->getWikiText( false, false, 'en' ),
 527                                                 [
 528                                                         'username' => $userName,
 529                                                 ]
 530                                         );
 531                                 }
 532                                 $user->setId( $id );
 533                                 $user->loadFromId( User::READ_LATEST );
 534                                 return false;
 535                                 // @codeCoverageIgnoreEnd
 536                         }
 537                 } catch ( \Exception $ex ) {
 538                         // @codeCoverageIgnoreStart
 539                         $logger->error( __METHOD__ . ': failed with exception {exception}', [
 540                                 'exception' => $ex,
 541                                 'username' => $userName,
 542                         ] );
 543                         // Do not keep throwing errors for a while
 544                         $cache->set( $backoffKey, 1, 600 );
 545                         // Bubble up error; which should normally trigger DB rollbacks
 546                         throw $ex;
 547                         // @codeCoverageIgnoreEnd
 548                 }
 549
 550                 # Notify AuthPlugin
 551                 // @codeCoverageIgnoreStart
 552                 $tmpUser = $user;
 553                 $wgAuth->initUser( $tmpUser, true );
 554                 if ( $tmpUser !== $user ) {
 555                         $logger->warning( __METHOD__ . ': ' .
 556                                 get_class( $wgAuth ) . '::initUser() replaced the user object' );
 557                 }
 558                 // @codeCoverageIgnoreEnd
 559
 560                 # Notify hooks (e.g. Newuserlog)
 561                 \Hooks::run( 'AuthPluginAutoCreate', [ $user ] );
 562                 \Hooks::run( 'LocalUserCreated', [ $user, true ] );
 563
 564                 $user->saveSettings();
 565
 566                 # Update user count
 567                 \DeferredUpdates::addUpdate( new \SiteStatsUpdate( 0, 0, 0, 0, 1 ) );
 568
 569                 # Watch user's userpage and talk page
 570                 $user->addWatch( $user->getUserPage(), User::IGNORE_USER_RIGHTS );
 571
 572                 return true;
 573         }
 574
 575         /**
 576          * Prevent future sessions for the user
 577          *
 578          * The intention is that the named account will never again be usable for
 579          * normal login (i.e. there is no way to undo the prevention of access).
 580          *
 581          * @private For use from \User::newSystemUser only
 582          * @param string $username
 583          */
 584         public function preventSessionsForUser( $username ) {
 585                 $this->preventUsers[$username] = true;
 586
 587                 // Instruct the session providers to kill any other sessions too.
 588                 foreach ( $this->getProviders() as $provider ) {
 589                         $provider->preventSessionsForUser( $username );
 590                 }
 591         }
 592
 593         /**
 594          * Test if a user is prevented
 595          * @private For use from SessionBackend only
 596          * @param string $username
 597          * @return bool
 598          */
 599         public function isUserSessionPrevented( $username ) {
 600                 return !empty( $this->preventUsers[$username] );
 601         }
 602
 603         /**
 604          * Get the available SessionProviders
 605          * @return SessionProvider[]
 606          */
 607         protected function getProviders() {
 608                 if ( $this->sessionProviders === null ) {
 609                         $this->sessionProviders = [];
 610                         foreach ( $this->config->get( 'SessionProviders' ) as $spec ) {
 611                                 $provider = \ObjectFactory::getObjectFromSpec( $spec );
 612                                 $provider->setLogger( $this->logger );
 613                                 $provider->setConfig( $this->config );
 614                                 $provider->setManager( $this );
 615                                 if ( isset( $this->sessionProviders[(string)$provider] ) ) {
 616                                         throw new \UnexpectedValueException( "Duplicate provider name \"$provider\"" );
 617                                 }
 618                                 $this->sessionProviders[(string)$provider] = $provider;
 619                         }
 620                 }
 621                 return $this->sessionProviders;
 622         }
 623
 624         /**
 625          * Get a session provider by name
 626          *
 627          * Generally, this will only be used by internal implementation of some
 628          * special session-providing mechanism. General purpose code, if it needs
 629          * to access a SessionProvider at all, will use Session::getProvider().
 630          *
 631          * @param string $name
 632          * @return SessionProvider|null
 633          */
 634         public function getProvider( $name ) {
 635                 $providers = $this->getProviders();
 636                 return isset( $providers[$name] ) ? $providers[$name] : null;
 637         }
 638
 639         /**
 640          * Save all active sessions on shutdown
 641          * @private For internal use with register_shutdown_function()
 642          */
 643         public function shutdown() {
 644                 if ( $this->allSessionBackends ) {
 645                         $this->logger->debug( 'Saving all sessions on shutdown' );
 646                         if ( session_id() !== '' ) {
 647                                 // @codeCoverageIgnoreStart
 648                                 session_write_close();
 649                         }
 650                         // @codeCoverageIgnoreEnd
 651                         foreach ( $this->allSessionBackends as $backend ) {
 652                                 $backend->shutdown();
 653                         }
 654                 }
 655         }
 656
 657         /**
 658          * Fetch the SessionInfo(s) for a request
 659          * @param WebRequest $request
 660          * @return SessionInfo|null
 661          */
 662         private function getSessionInfoForRequest( WebRequest $request ) {
 663                 // Call all providers to fetch "the" session
 664                 $infos = [];
 665                 foreach ( $this->getProviders() as $provider ) {
 666                         $info = $provider->provideSessionInfo( $request );
 667                         if ( !$info ) {
 668                                 continue;
 669                         }
 670                         if ( $info->getProvider() !== $provider ) {
 671                                 throw new \UnexpectedValueException(
 672                                         "$provider returned session info for a different provider: $info"
 673                                 );
 674                         }
 675                         $infos[] = $info;
 676                 }
 677
 678                 // Sort the SessionInfos. Then find the first one that can be
 679                 // successfully loaded, and then all the ones after it with the same
 680                 // priority.
 681                 usort( $infos, 'MediaWiki\\Session\\SessionInfo::compare' );
 682                 $retInfos = [];
 683                 while ( $infos ) {
 684                         $info = array_pop( $infos );
 685                         if ( $this->loadSessionInfoFromStore( $info, $request ) ) {
 686                                 $retInfos[] = $info;
 687                                 while ( $infos ) {
 688                                         $info = array_pop( $infos );
 689                                         if ( SessionInfo::compare( $retInfos[0], $info ) ) {
 690                                                 // We hit a lower priority, stop checking.
 691                                                 break;
 692                                         }
 693                                         if ( $this->loadSessionInfoFromStore( $info, $request ) ) {
 694                                                 // This is going to error out below, but we want to
 695                                                 // provide a complete list.
 696                                                 $retInfos[] = $info;
 697                                         } else {
 698                                                 // Session load failed, so unpersist it from this request
 699                                                 $info->getProvider()->unpersistSession( $request );
 700                                         }
 701                                 }
 702                         } else {
 703                                 // Session load failed, so unpersist it from this request
 704                                 $info->getProvider()->unpersistSession( $request );
 705                         }
 706                 }
 707
 708                 if ( count( $retInfos ) > 1 ) {
 709                         $ex = new \OverflowException(
 710                                 'Multiple sessions for this request tied for top priority: ' . implode( ', ', $retInfos )
 711                         );
 712                         $ex->sessionInfos = $retInfos;
 713                         throw $ex;
 714                 }
 715
 716                 return $retInfos ? $retInfos[0] : null;
 717         }
 718
 719         /**
 720          * Load and verify the session info against the store
 721          *
 722          * @param SessionInfo &$info Will likely be replaced with an updated SessionInfo instance
 723          * @param WebRequest $request
 724          * @return bool Whether the session info matches the stored data (if any)
 725          */
 726         private function loadSessionInfoFromStore( SessionInfo &$info, WebRequest $request ) {
 727                 $key = wfMemcKey( 'MWSession', $info->getId() );
 728                 $blob = $this->store->get( $key );
 729
 730                 // If we got data from the store and the SessionInfo says to force use,
 731                 // "fail" means to delete the data from the store and retry. Otherwise,
 732                 // "fail" is just return false.
 733                 if ( $info->forceUse() && $blob !== false ) {
 734                         $failHandler = function () use ( $key, &$info, $request ) {
 735                                 $this->store->delete( $key );
 736                                 return $this->loadSessionInfoFromStore( $info, $request );
 737                         };
 738                 } else {
 739                         $failHandler = function () {
 740                                 return false;
 741                         };
 742                 }
 743
 744                 $newParams = [];
 745
 746                 if ( $blob !== false ) {
 747                         // Sanity check: blob must be an array, if it's saved at all
 748                         if ( !is_array( $blob ) ) {
 749                                 $this->logger->warning( 'Session "{session}": Bad data', [
 750                                         'session' => $info,
 751                                 ] );
 752                                 $this->store->delete( $key );
 753                                 return $failHandler();
 754                         }
 755
 756                         // Sanity check: blob has data and metadata arrays
 757                         if ( !isset( $blob['data'] ) || !is_array( $blob['data'] ) ||
 758                                 !isset( $blob['metadata'] ) || !is_array( $blob['metadata'] )
 759                         ) {
 760                                 $this->logger->warning( 'Session "{session}": Bad data structure', [
 761                                         'session' => $info,
 762                                 ] );
 763                                 $this->store->delete( $key );
 764                                 return $failHandler();
 765                         }
 766
 767                         $data = $blob['data'];
 768                         $metadata = $blob['metadata'];
 769
 770                         // Sanity check: metadata must be an array and must contain certain
 771                         // keys, if it's saved at all
 772                         if ( !array_key_exists( 'userId', $metadata ) ||
 773                                 !array_key_exists( 'userName', $metadata ) ||
 774                                 !array_key_exists( 'userToken', $metadata ) ||
 775                                 !array_key_exists( 'provider', $metadata )
 776                         ) {
 777                                 $this->logger->warning( 'Session "{session}": Bad metadata', [
 778                                         'session' => $info,
 779                                 ] );
 780                                 $this->store->delete( $key );
 781                                 return $failHandler();
 782                         }
 783
 784                         // First, load the provider from metadata, or validate it against the metadata.
 785                         $provider = $info->getProvider();
 786                         if ( $provider === null ) {
 787                                 $newParams['provider'] = $provider = $this->getProvider( $metadata['provider'] );
 788                                 if ( !$provider ) {
 789                                         $this->logger->warning(
 790                                                 'Session "{session}": Unknown provider ' . $metadata['provider'],
 791                                                 [
 792                                                         'session' => $info,
 793                                                 ]
 794                                         );
 795                                         $this->store->delete( $key );
 796                                         return $failHandler();
 797                                 }
 798                         } elseif ( $metadata['provider'] !== (string)$provider ) {
 799                                 $this->logger->warning( 'Session "{session}": Wrong provider ' .
 800                                         $metadata['provider'] . ' !== ' . $provider,
 801                                         [
 802                                                 'session' => $info,
 803                                 ] );
 804                                 return $failHandler();
 805                         }
 806
 807                         // Load provider metadata from metadata, or validate it against the metadata
 808                         $providerMetadata = $info->getProviderMetadata();
 809                         if ( isset( $metadata['providerMetadata'] ) ) {
 810                                 if ( $providerMetadata === null ) {
 811                                         $newParams['metadata'] = $metadata['providerMetadata'];
 812                                 } else {
 813                                         try {
 814                                                 $newProviderMetadata = $provider->mergeMetadata(
 815                                                         $metadata['providerMetadata'], $providerMetadata
 816                                                 );
 817                                                 if ( $newProviderMetadata !== $providerMetadata ) {
 818                                                         $newParams['metadata'] = $newProviderMetadata;
 819                                                 }
 820                                         } catch ( MetadataMergeException $ex ) {
 821                                                 $this->logger->warning(
 822                                                         'Session "{session}": Metadata merge failed: {exception}',
 823                                                         [
 824                                                                 'session' => $info,
 825                                                                 'exception' => $ex,
 826                                                         ] + $ex->getContext()
 827                                                 );
 828                                                 return $failHandler();
 829                                         }
 830                                 }
 831                         }
 832
 833                         // Next, load the user from metadata, or validate it against the metadata.
 834                         $userInfo = $info->getUserInfo();
 835                         if ( !$userInfo ) {
 836                                 // For loading, id is preferred to name.
 837                                 try {
 838                                         if ( $metadata['userId'] ) {
 839                                                 $userInfo = UserInfo::newFromId( $metadata['userId'] );
 840                                         } elseif ( $metadata['userName'] !== null ) { // Shouldn't happen, but just in case
 841                                                 $userInfo = UserInfo::newFromName( $metadata['userName'] );
 842                                         } else {
 843                                                 $userInfo = UserInfo::newAnonymous();
 844                                         }
 845                                 } catch ( \InvalidArgumentException $ex ) {
 846                                         $this->logger->error( 'Session "{session}": {exception}', [
 847                                                 'session' => $info,
 848                                                 'exception' => $ex,
 849                                         ] );
 850                                         return $failHandler();
 851                                 }
 852                                 $newParams['userInfo'] = $userInfo;
 853                         } else {
 854                                 // User validation passes if user ID matches, or if there
 855                                 // is no saved ID and the names match.
 856                                 if ( $metadata['userId'] ) {
 857                                         if ( $metadata['userId'] !== $userInfo->getId() ) {
 858                                                 $this->logger->warning(
 859                                                         'Session "{session}": User ID mismatch, {uid_a} !== {uid_b}',
 860                                                         [
 861                                                                 'session' => $info,
 862                                                                 'uid_a' => $metadata['userId'],
 863                                                                 'uid_b' => $userInfo->getId(),
 864                                                 ] );
 865                                                 return $failHandler();
 866                                         }
 867
 868                                         // If the user was renamed, probably best to fail here.
 869                                         if ( $metadata['userName'] !== null &&
 870                                                 $userInfo->getName() !== $metadata['userName']
 871                                         ) {
 872                                                 $this->logger->warning(
 873                                                         'Session "{session}": User ID matched but name didn\'t (rename?), {uname_a} !== {uname_b}',
 874                                                         [
 875                                                                 'session' => $info,
 876                                                                 'uname_a' => $metadata['userName'],
 877                                                                 'uname_b' => $userInfo->getName(),
 878                                                 ] );
 879                                                 return $failHandler();
 880                                         }
 881
 882                                 } elseif ( $metadata['userName'] !== null ) { // Shouldn't happen, but just in case
 883                                         if ( $metadata['userName'] !== $userInfo->getName() ) {
 884                                                 $this->logger->warning(
 885                                                         'Session "{session}": User name mismatch, {uname_a} !== {uname_b}',
 886                                                         [
 887                                                                 'session' => $info,
 888                                                                 'uname_a' => $metadata['userName'],
 889                                                                 'uname_b' => $userInfo->getName(),
 890                                                 ] );
 891                                                 return $failHandler();
 892                                         }
 893                                 } elseif ( !$userInfo->isAnon() ) {
 894                                         // Metadata specifies an anonymous user, but the passed-in
 895                                         // user isn't anonymous.
 896                                         $this->logger->warning(
 897                                                 'Session "{session}": Metadata has an anonymous user, but a non-anon user was provided',
 898                                                 [
 899                                                         'session' => $info,
 900                                         ] );
 901                                         return $failHandler();
 902                                 }
 903                         }
 904
 905                         // And if we have a token in the metadata, it must match the loaded/provided user.
 906                         if ( $metadata['userToken'] !== null &&
 907                                 $userInfo->getToken() !== $metadata['userToken']
 908                         ) {
 909                                 $this->logger->warning( 'Session "{session}": User token mismatch', [
 910                                         'session' => $info,
 911                                 ] );
 912                                 return $failHandler();
 913                         }
 914                         if ( !$userInfo->isVerified() ) {
 915                                 $newParams['userInfo'] = $userInfo->verified();
 916                         }
 917
 918                         if ( !empty( $metadata['remember'] ) && !$info->wasRemembered() ) {
 919                                 $newParams['remembered'] = true;
 920                         }
 921                         if ( !empty( $metadata['forceHTTPS'] ) && !$info->forceHTTPS() ) {
 922                                 $newParams['forceHTTPS'] = true;
 923                         }
 924                         if ( !empty( $metadata['persisted'] ) && !$info->wasPersisted() ) {
 925                                 $newParams['persisted'] = true;
 926                         }
 927
 928                         if ( !$info->isIdSafe() ) {
 929                                 $newParams['idIsSafe'] = true;
 930                         }
 931                 } else {
 932                         // No metadata, so we can't load the provider if one wasn't given.
 933                         if ( $info->getProvider() === null ) {
 934                                 $this->logger->warning(
 935                                         'Session "{session}": Null provider and no metadata',
 936                                         [
 937                                                 'session' => $info,
 938                                 ] );
 939                                 return $failHandler();
 940                         }
 941
 942                         // If no user was provided and no metadata, it must be anon.
 943                         if ( !$info->getUserInfo() ) {
 944                                 if ( $info->getProvider()->canChangeUser() ) {
 945                                         $newParams['userInfo'] = UserInfo::newAnonymous();
 946                                 } else {
 947                                         $this->logger->info(
 948                                                 'Session "{session}": No user provided and provider cannot set user',
 949                                                 [
 950                                                         'session' => $info,
 951                                         ] );
 952                                         return $failHandler();
 953                                 }
 954                         } elseif ( !$info->getUserInfo()->isVerified() ) {
 955                                 $this->logger->warning(
 956                                         'Session "{session}": Unverified user provided and no metadata to auth it',
 957                                         [
 958                                                 'session' => $info,
 959                                 ] );
 960                                 return $failHandler();
 961                         }
 962
 963                         $data = false;
 964                         $metadata = false;
 965
 966                         if ( !$info->getProvider()->persistsSessionId() && !$info->isIdSafe() ) {
 967                                 // The ID doesn't come from the user, so it should be safe
 968                                 // (and if not, nothing we can do about it anyway)
 969                                 $newParams['idIsSafe'] = true;
 970                         }
 971                 }
 972
 973                 // Construct the replacement SessionInfo, if necessary
 974                 if ( $newParams ) {
 975                         $newParams['copyFrom'] = $info;
 976                         $info = new SessionInfo( $info->getPriority(), $newParams );
 977                 }
 978
 979                 // Allow the provider to check the loaded SessionInfo
 980                 $providerMetadata = $info->getProviderMetadata();
 981                 if ( !$info->getProvider()->refreshSessionInfo( $info, $request, $providerMetadata ) ) {
 982                         return $failHandler();
 983                 }
 984                 if ( $providerMetadata !== $info->getProviderMetadata() ) {
 985                         $info = new SessionInfo( $info->getPriority(), [
 986                                 'metadata' => $providerMetadata,
 987                                 'copyFrom' => $info,
 988                         ] );
 989                 }
 990
 991                 // Give hooks a chance to abort. Combined with the SessionMetadata
 992                 // hook, this can allow for tying a session to an IP address or the
 993                 // like.
 994                 $reason = 'Hook aborted';
 995                 if ( !\Hooks::run(
 996                         'SessionCheckInfo',
 997                         [ &$reason, $info, $request, $metadata, $data ]
 998                 ) ) {
 999                         $this->logger->warning( 'Session "{session}": ' . $reason, [
1000                                 'session' => $info,
1001                         ] );
1002                         return $failHandler();
1003                 }
1004
1005                 return true;
1006         }
1007
1008         /**
1009          * Create a session corresponding to the passed SessionInfo
1010          * @private For use by a SessionProvider that needs to specially create its
1011          *  own session.
1012          * @param SessionInfo $info
1013          * @param WebRequest $request
1014          * @return Session
1015          */
1016         public function getSessionFromInfo( SessionInfo $info, WebRequest $request ) {
1017                 // @codeCoverageIgnoreStart
1018                 if ( defined( 'MW_NO_SESSION' ) ) {
1019                         if ( MW_NO_SESSION === 'warn' ) {
1020                                 // Undocumented safety case for converting existing entry points
1021                                 $this->logger->error( 'Sessions are supposed to be disabled for this entry point', [
1022                                         'exception' => new \BadMethodCallException( 'Sessions are disabled for this entry point' ),
1023                                 ] );
1024                         } else {
1025                                 throw new \BadMethodCallException( 'Sessions are disabled for this entry point' );
1026                         }
1027                 }
1028                 // @codeCoverageIgnoreEnd
1029
1030                 $id = $info->getId();
1031
1032                 if ( !isset( $this->allSessionBackends[$id] ) ) {
1033                         if ( !isset( $this->allSessionIds[$id] ) ) {
1034                                 $this->allSessionIds[$id] = new SessionId( $id );
1035                         }
1036                         $backend = new SessionBackend(
1037                                 $this->allSessionIds[$id],
1038                                 $info,
1039                                 $this->store,
1040                                 $this->logger,
1041                                 $this->config->get( 'ObjectCacheSessionExpiry' )
1042                         );
1043                         $this->allSessionBackends[$id] = $backend;
1044                         $delay = $backend->delaySave();
1045                 } else {
1046                         $backend = $this->allSessionBackends[$id];
1047                         $delay = $backend->delaySave();
1048                         if ( $info->wasPersisted() ) {
1049                                 $backend->persist();
1050                         }
1051                         if ( $info->wasRemembered() ) {
1052                                 $backend->setRememberUser( true );
1053                         }
1054                 }
1055
1056                 $request->setSessionId( $backend->getSessionId() );
1057                 $session = $backend->getSession( $request );
1058
1059                 if ( !$info->isIdSafe() ) {
1060                         $session->resetId();
1061                 }
1062
1063                 \ScopedCallback::consume( $delay );
1064                 return $session;
1065         }
1066
1067         /**
1068          * Deregister a SessionBackend
1069          * @private For use from \MediaWiki\Session\SessionBackend only
1070          * @param SessionBackend $backend
1071          */
1072         public function deregisterSessionBackend( SessionBackend $backend ) {
1073                 $id = $backend->getId();
1074                 if ( !isset( $this->allSessionBackends[$id] ) || !isset( $this->allSessionIds[$id] ) ||
1075                         $this->allSessionBackends[$id] !== $backend ||
1076                         $this->allSessionIds[$id] !== $backend->getSessionId()
1077                 ) {
1078                         throw new \InvalidArgumentException( 'Backend was not registered with this SessionManager' );
1079                 }
1080
1081                 unset( $this->allSessionBackends[$id] );
1082                 // Explicitly do not unset $this->allSessionIds[$id]
1083         }
1084
1085         /**
1086          * Change a SessionBackend's ID
1087          * @private For use from \MediaWiki\Session\SessionBackend only
1088          * @param SessionBackend $backend
1089          */
1090         public function changeBackendId( SessionBackend $backend ) {
1091                 $sessionId = $backend->getSessionId();
1092                 $oldId = (string)$sessionId;
1093                 if ( !isset( $this->allSessionBackends[$oldId] ) || !isset( $this->allSessionIds[$oldId] ) ||
1094                         $this->allSessionBackends[$oldId] !== $backend ||
1095                         $this->allSessionIds[$oldId] !== $sessionId
1096                 ) {
1097                         throw new \InvalidArgumentException( 'Backend was not registered with this SessionManager' );
1098                 }
1099
1100                 $newId = $this->generateSessionId();
1101
1102                 unset( $this->allSessionBackends[$oldId], $this->allSessionIds[$oldId] );
1103                 $sessionId->setId( $newId );
1104                 $this->allSessionBackends[$newId] = $backend;
1105                 $this->allSessionIds[$newId] = $sessionId;
1106         }
1107
1108         /**
1109          * Generate a new random session ID
1110          * @return string
1111          */
1112         public function generateSessionId() {
1113                 do {
1114                         $id = \Wikimedia\base_convert( \MWCryptRand::generateHex( 40 ), 16, 32, 32 );
1115                         $key = wfMemcKey( 'MWSession', $id );
1116                 } while ( isset( $this->allSessionIds[$id] ) || is_array( $this->store->get( $key ) ) );
1117                 return $id;
1118         }
1119
1120         /**
1121          * Call setters on a PHPSessionHandler
1122          * @private Use PhpSessionHandler::install()
1123          * @param PHPSessionHandler $handler
1124          */
1125         public function setupPHPSessionHandler( PHPSessionHandler $handler ) {
1126                 $handler->setManager( $this, $this->store, $this->logger );
1127         }
1128
1129         /**
1130          * Reset the internal caching for unit testing
1131          */
1132         public static function resetCache() {
1133                 if ( !defined( 'MW_PHPUNIT_TEST' ) ) {
1134                         // @codeCoverageIgnoreStart
1135                         throw new MWException( __METHOD__ . ' may only be called from unit tests!' );
1136                         // @codeCoverageIgnoreEnd
1137                 }
1138
1139                 self::$globalSession = null;
1140                 self::$globalSessionRequest = null;
1141         }
1142
1143         /**@}*/
1144
1145 }