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