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