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