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 Psr\Log\LogLevel;
  28 use BagOStuff;
  29 use CachedBagOStuff;
  30 use Config;
  31 use FauxRequest;
  32 use User;
  33 use WebRequest;
  34
  35 /**
  36  * This serves as the entry point to the MediaWiki session handling system.
  37  *
  38  * @ingroup Session
  39  * @since 1.27
  40  */
  41 final class SessionManager implements SessionManagerInterface {
  42         /** @var SessionManager|null */
  43         private static $instance = null;
  44
  45         /** @var Session|null */
  46         private static $globalSession = null;
  47
  48         /** @var WebRequest|null */
  49         private static $globalSessionRequest = null;
  50
  51         /** @var LoggerInterface */
  52         private $logger;
  53
  54         /** @var Config */
  55         private $config;
  56
  57         /** @var CachedBagOStuff|null */
  58         private $store;
  59
  60         /** @var SessionProvider[] */
  61         private $sessionProviders = null;
  62
  63         /** @var string[] */
  64         private $varyCookies = null;
  65
  66         /** @var array */
  67         private $varyHeaders = null;
  68
  69         /** @var SessionBackend[] */
  70         private $allSessionBackends = [];
  71
  72         /** @var SessionId[] */
  73         private $allSessionIds = [];
  74
  75         /** @var string[] */
  76         private $preventUsers = [];
  77
  78         /**
  79          * Get the global SessionManager
  80          * @return SessionManagerInterface
  81          *  (really a SessionManager, but this is to make IDEs less confused)
  82          */
  83         public static function singleton() {
  84                 if ( self::$instance === null ) {
  85                         self::$instance = new self();
  86                 }
  87                 return self::$instance;
  88         }
  89
  90         /**
  91          * Get the "global" session
  92          *
  93          * If PHP's session_id() has been set, returns that session. Otherwise
  94          * returns the session for RequestContext::getMain()->getRequest().
  95          *
  96          * @return Session
  97          */
  98         public static function getGlobalSession() {
  99                 if ( !PHPSessionHandler::isEnabled() ) {
 100                         $id = '';
 101                 } else {
 102                         $id = session_id();
 103                 }
 104
 105                 $request = \RequestContext::getMain()->getRequest();
 106                 if (
 107                         !self::$globalSession // No global session is set up yet
 108                         || self::$globalSessionRequest !== $request // The global WebRequest changed
 109                         || $id !== '' && self::$globalSession->getId() !== $id // Someone messed with session_id()
 110                 ) {
 111                         self::$globalSessionRequest = $request;
 112                         if ( $id === '' ) {
 113                                 // session_id() wasn't used, so fetch the Session from the WebRequest.
 114                                 // We use $request->getSession() instead of $singleton->getSessionForRequest()
 115                                 // because doing the latter would require a public
 116                                 // "$request->getSessionId()" method that would confuse end
 117                                 // users by returning SessionId|null where they'd expect it to
 118                                 // be short for $request->getSession()->getId(), and would
 119                                 // wind up being a duplicate of the code in
 120                                 // $request->getSession() anyway.
 121                                 self::$globalSession = $request->getSession();
 122                         } else {
 123                                 // Someone used session_id(), so we need to follow suit.
 124                                 // Note this overwrites whatever session might already be
 125                                 // associated with $request with the one for $id.
 126                                 self::$globalSession = self::singleton()->getSessionById( $id, true, $request )
 127                                         ?: $request->getSession();
 128                         }
 129                 }
 130                 return self::$globalSession;
 131         }
 132
 133         /**
 134          * @param array $options
 135          *  - config: Config to fetch configuration from. Defaults to the default 'main' config.
 136          *  - logger: LoggerInterface to use for logging. Defaults to the 'session' channel.
 137          *  - store: BagOStuff to store session data in.
 138          */
 139         public function __construct( $options = [] ) {
 140                 if ( isset( $options['config'] ) ) {
 141                         $this->config = $options['config'];
 142                         if ( !$this->config instanceof Config ) {
 143                                 throw new \InvalidArgumentException(
 144                                         '$options[\'config\'] must be an instance of Config'
 145                                 );
 146                         }
 147                 } else {
 148                         $this->config = \ConfigFactory::getDefaultInstance()->makeConfig( 'main' );
 149                 }
 150
 151                 if ( isset( $options['logger'] ) ) {
 152                         if ( !$options['logger'] instanceof LoggerInterface ) {
 153                                 throw new \InvalidArgumentException(
 154                                         '$options[\'logger\'] must be an instance of LoggerInterface'
 155                                 );
 156                         }
 157                         $this->setLogger( $options['logger'] );
 158                 } else {
 159                         $this->setLogger( \MediaWiki\Logger\LoggerFactory::getInstance( 'session' ) );
 160                 }
 161
 162                 if ( isset( $options['store'] ) ) {
 163                         if ( !$options['store'] instanceof BagOStuff ) {
 164                                 throw new \InvalidArgumentException(
 165                                         '$options[\'store\'] must be an instance of BagOStuff'
 166                                 );
 167                         }
 168                         $store = $options['store'];
 169                 } else {
 170                         $store = \ObjectCache::getInstance( $this->config->get( 'SessionCacheType' ) );
 171                 }
 172                 $this->store = $store instanceof CachedBagOStuff ? $store : new CachedBagOStuff( $store );
 173
 174                 register_shutdown_function( [ $this, 'shutdown' ] );
 175         }
 176
 177         public function setLogger( LoggerInterface $logger ) {
 178                 $this->logger = $logger;
 179         }
 180
 181         public function getSessionForRequest( WebRequest $request ) {
 182                 $info = $this->getSessionInfoForRequest( $request );
 183
 184                 if ( !$info ) {
 185                         $session = $this->getEmptySession( $request );
 186                 } else {
 187                         $session = $this->getSessionFromInfo( $info, $request );
 188                 }
 189                 return $session;
 190         }
 191
 192         public function getSessionById( $id, $create = false, WebRequest $request = null ) {
 193                 if ( !self::validateSessionId( $id ) ) {
 194                         throw new \InvalidArgumentException( 'Invalid session ID' );
 195                 }
 196                 if ( !$request ) {
 197                         $request = new FauxRequest;
 198                 }
 199
 200                 $session = null;
 201
 202                 // Test this here to provide a better log message for the common case
 203                 // of "no such ID"
 204                 $key = wfMemcKey( 'MWSession', $id );
 205                 if ( is_array( $this->store->get( $key ) ) ) {
 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                 if ( $this->varyHeaders === null ) {
 301                         $headers = [];
 302                         foreach ( $this->getProviders() as $provider ) {
 303                                 foreach ( $provider->getVaryHeaders() as $header => $options ) {
 304                                         if ( !isset( $headers[$header] ) ) {
 305                                                 $headers[$header] = [];
 306                                         }
 307                                         if ( is_array( $options ) ) {
 308                                                 $headers[$header] = array_unique( array_merge( $headers[$header], $options ) );
 309                                         }
 310                                 }
 311                         }
 312                         $this->varyHeaders = $headers;
 313                 }
 314                 return $this->varyHeaders;
 315         }
 316
 317         public function getVaryCookies() {
 318                 if ( $this->varyCookies === null ) {
 319                         $cookies = [];
 320                         foreach ( $this->getProviders() as $provider ) {
 321                                 $cookies = array_merge( $cookies, $provider->getVaryCookies() );
 322                         }
 323                         $this->varyCookies = array_values( array_unique( $cookies ) );
 324                 }
 325                 return $this->varyCookies;
 326         }
 327
 328         /**
 329          * Validate a session ID
 330          * @param string $id
 331          * @return bool
 332          */
 333         public static function validateSessionId( $id ) {
 334                 return is_string( $id ) && preg_match( '/^[a-zA-Z0-9_-]{32,}$/', $id );
 335         }
 336
 337         /**
 338          * @name Internal methods
 339          * @{
 340          */
 341
 342         /**
 343          * Auto-create the given user, if necessary
 344          * @private Don't call this yourself. Let Setup.php do it for you at the right time.
 345          * @note This more properly belongs in AuthManager, but we need it now.
 346          *  When AuthManager comes, this will be deprecated and will pass-through
 347          *  to the corresponding AuthManager method.
 348          * @param User $user User to auto-create
 349          * @return bool Success
 350          */
 351         public static function autoCreateUser( User $user ) {
 352                 global $wgAuth;
 353
 354                 $logger = self::singleton()->logger;
 355
 356                 // Much of this code is based on that in CentralAuth
 357
 358                 // Try the local user from the slave DB
 359                 $localId = User::idFromName( $user->getName() );
 360                 $flags = 0;
 361
 362                 // Fetch the user ID from the master, so that we don't try to create the user
 363                 // when they already exist, due to replication lag
 364                 // @codeCoverageIgnoreStart
 365                 if ( !$localId && wfGetLB()->getReaderIndex() != 0 ) {
 366                         $localId = User::idFromName( $user->getName(), User::READ_LATEST );
 367                         $flags = User::READ_LATEST;
 368                 }
 369                 // @codeCoverageIgnoreEnd
 370
 371                 if ( $localId ) {
 372                         // User exists after all.
 373                         $user->setId( $localId );
 374                         $user->loadFromId( $flags );
 375                         return false;
 376                 }
 377
 378                 // Denied by AuthPlugin? But ignore AuthPlugin itself.
 379                 if ( get_class( $wgAuth ) !== 'AuthPlugin' && !$wgAuth->autoCreate() ) {
 380                         $logger->debug( __METHOD__ . ': denied by AuthPlugin' );
 381                         $user->setId( 0 );
 382                         $user->loadFromId();
 383                         return false;
 384                 }
 385
 386                 // Wiki is read-only?
 387                 if ( wfReadOnly() ) {
 388                         $logger->debug( __METHOD__ . ': denied by wfReadOnly()' );
 389                         $user->setId( 0 );
 390                         $user->loadFromId();
 391                         return false;
 392                 }
 393
 394                 $userName = $user->getName();
 395
 396                 // Check the session, if we tried to create this user already there's
 397                 // no point in retrying.
 398                 $session = self::getGlobalSession();
 399                 $reason = $session->get( 'MWSession::AutoCreateBlacklist' );
 400                 if ( $reason ) {
 401                         $logger->debug( __METHOD__ . ": blacklisted in session ($reason)" );
 402                         $user->setId( 0 );
 403                         $user->loadFromId();
 404                         return false;
 405                 }
 406
 407                 // Is the IP user able to create accounts?
 408                 $anon = new User;
 409                 if ( !$anon->isAllowedAny( 'createaccount', 'autocreateaccount' )
 410                         || $anon->isBlockedFromCreateAccount()
 411                 ) {
 412                         // Blacklist the user to avoid repeated DB queries subsequently
 413                         $logger->debug( __METHOD__ . ': user is blocked from this wiki, blacklisting' );
 414                         $session->set( 'MWSession::AutoCreateBlacklist', 'blocked', 600 );
 415                         $session->persist();
 416                         $user->setId( 0 );
 417                         $user->loadFromId();
 418                         return false;
 419                 }
 420
 421                 // Check for validity of username
 422                 if ( !User::isCreatableName( $userName ) ) {
 423                         $logger->debug( __METHOD__ . ': Invalid username, blacklisting' );
 424                         $session->set( 'MWSession::AutoCreateBlacklist', 'invalid username', 600 );
 425                         $session->persist();
 426                         $user->setId( 0 );
 427                         $user->loadFromId();
 428                         return false;
 429                 }
 430
 431                 // Give other extensions a chance to stop auto creation.
 432                 $user->loadDefaults( $userName );
 433                 $abortMessage = '';
 434                 if ( !\Hooks::run( 'AbortAutoAccount', [ $user, &$abortMessage ] ) ) {
 435                         // In this case we have no way to return the message to the user,
 436                         // but we can log it.
 437                         $logger->debug( __METHOD__ . ": denied by hook: $abortMessage" );
 438                         $session->set( 'MWSession::AutoCreateBlacklist', "hook aborted: $abortMessage", 600 );
 439                         $session->persist();
 440                         $user->setId( 0 );
 441                         $user->loadFromId();
 442                         return false;
 443                 }
 444
 445                 // Make sure the name has not been changed
 446                 if ( $user->getName() !== $userName ) {
 447                         $user->setId( 0 );
 448                         $user->loadFromId();
 449                         throw new \UnexpectedValueException(
 450                                 'AbortAutoAccount hook tried to change the user name'
 451                         );
 452                 }
 453
 454                 // Ignore warnings about master connections/writes...hard to avoid here
 455                 \Profiler::instance()->getTransactionProfiler()->resetExpectations();
 456
 457                 $cache = \ObjectCache::getLocalClusterInstance();
 458                 $backoffKey = wfMemcKey( 'MWSession', 'autocreate-failed', md5( $userName ) );
 459                 if ( $cache->get( $backoffKey ) ) {
 460                         $logger->debug( __METHOD__ . ': denied by prior creation attempt failures' );
 461                         $user->setId( 0 );
 462                         $user->loadFromId();
 463                         return false;
 464                 }
 465
 466                 // Checks passed, create the user...
 467                 $from = isset( $_SERVER['REQUEST_URI'] ) ? $_SERVER['REQUEST_URI'] : 'CLI';
 468                 $logger->info( __METHOD__ . ': creating new user ({username}) - from: {url}',
 469                         [
 470                                 'username' => $userName,
 471                                 'url' => $from,
 472                 ] );
 473
 474                 try {
 475                         // Insert the user into the local DB master
 476                         $status = $user->addToDatabase();
 477                         if ( !$status->isOK() ) {
 478                                 // @codeCoverageIgnoreStart
 479                                 // double-check for a race condition (T70012)
 480                                 $id = User::idFromName( $user->getName(), User::READ_LATEST );
 481                                 if ( $id ) {
 482                                         $logger->info( __METHOD__ . ': tried to autocreate existing user',
 483                                                 [
 484                                                         'username' => $userName,
 485                                                 ] );
 486                                 } else {
 487                                         $logger->error( __METHOD__ . ': failed with message ' . $status->getWikiText(),
 488                                                 [
 489                                                         'username' => $userName,
 490                                                 ] );
 491                                 }
 492                                 $user->setId( $id );
 493                                 $user->loadFromId( User::READ_LATEST );
 494                                 return false;
 495                                 // @codeCoverageIgnoreEnd
 496                         }
 497                 } catch ( \Exception $ex ) {
 498                         // @codeCoverageIgnoreStart
 499                         $logger->error( __METHOD__ . ': failed with exception {exception}', [
 500                                 'exception' => $ex,
 501                                 'username' => $userName,
 502                         ] );
 503                         // Do not keep throwing errors for a while
 504                         $cache->set( $backoffKey, 1, 600 );
 505                         // Bubble up error; which should normally trigger DB rollbacks
 506                         throw $ex;
 507                         // @codeCoverageIgnoreEnd
 508                 }
 509
 510                 # Notify AuthPlugin
 511                 $tmpUser = $user;
 512                 $wgAuth->initUser( $tmpUser, true );
 513                 if ( $tmpUser !== $user ) {
 514                         $logger->warning( __METHOD__ . ': ' .
 515                                 get_class( $wgAuth ) . '::initUser() replaced the user object' );
 516                 }
 517
 518                 # Notify hooks (e.g. Newuserlog)
 519                 \Hooks::run( 'AuthPluginAutoCreate', [ $user ] );
 520                 \Hooks::run( 'LocalUserCreated', [ $user, true ] );
 521
 522                 $user->saveSettings();
 523
 524                 # Update user count
 525                 \DeferredUpdates::addUpdate( new \SiteStatsUpdate( 0, 0, 0, 0, 1 ) );
 526
 527                 # Watch user's userpage and talk page
 528                 $user->addWatch( $user->getUserPage(), \WatchedItem::IGNORE_USER_RIGHTS );
 529
 530                 return true;
 531         }
 532
 533         /**
 534          * Prevent future sessions for the user
 535          *
 536          * The intention is that the named account will never again be usable for
 537          * normal login (i.e. there is no way to undo the prevention of access).
 538          *
 539          * @private For use from \\User::newSystemUser only
 540          * @param string $username
 541          */
 542         public function preventSessionsForUser( $username ) {
 543                 $this->preventUsers[$username] = true;
 544
 545                 // Instruct the session providers to kill any other sessions too.
 546                 foreach ( $this->getProviders() as $provider ) {
 547                         $provider->preventSessionsForUser( $username );
 548                 }
 549         }
 550
 551         /**
 552          * Test if a user is prevented
 553          * @private For use from SessionBackend only
 554          * @param string $username
 555          * @return bool
 556          */
 557         public function isUserSessionPrevented( $username ) {
 558                 return !empty( $this->preventUsers[$username] );
 559         }
 560
 561         /**
 562          * Get the available SessionProviders
 563          * @return SessionProvider[]
 564          */
 565         protected function getProviders() {
 566                 if ( $this->sessionProviders === null ) {
 567                         $this->sessionProviders = [];
 568                         foreach ( $this->config->get( 'SessionProviders' ) as $spec ) {
 569                                 $provider = \ObjectFactory::getObjectFromSpec( $spec );
 570                                 $provider->setLogger( $this->logger );
 571                                 $provider->setConfig( $this->config );
 572                                 $provider->setManager( $this );
 573                                 if ( isset( $this->sessionProviders[(string)$provider] ) ) {
 574                                         throw new \UnexpectedValueException( "Duplicate provider name \"$provider\"" );
 575                                 }
 576                                 $this->sessionProviders[(string)$provider] = $provider;
 577                         }
 578                 }
 579                 return $this->sessionProviders;
 580         }
 581
 582         /**
 583          * Get a session provider by name
 584          *
 585          * Generally, this will only be used by internal implementation of some
 586          * special session-providing mechanism. General purpose code, if it needs
 587          * to access a SessionProvider at all, will use Session::getProvider().
 588          *
 589          * @param string $name
 590          * @return SessionProvider|null
 591          */
 592         public function getProvider( $name ) {
 593                 $providers = $this->getProviders();
 594                 return isset( $providers[$name] ) ? $providers[$name] : null;
 595         }
 596
 597         /**
 598          * Save all active sessions on shutdown
 599          * @private For internal use with register_shutdown_function()
 600          */
 601         public function shutdown() {
 602                 if ( $this->allSessionBackends ) {
 603                         $this->logger->debug( 'Saving all sessions on shutdown' );
 604                         if ( session_id() !== '' ) {
 605                                 // @codeCoverageIgnoreStart
 606                                 session_write_close();
 607                         }
 608                         // @codeCoverageIgnoreEnd
 609                         foreach ( $this->allSessionBackends as $backend ) {
 610                                 $backend->save( true );
 611                         }
 612                 }
 613         }
 614
 615         /**
 616          * Fetch the SessionInfo(s) for a request
 617          * @param WebRequest $request
 618          * @return SessionInfo|null
 619          */
 620         private function getSessionInfoForRequest( WebRequest $request ) {
 621                 // Call all providers to fetch "the" session
 622                 $infos = [];
 623                 foreach ( $this->getProviders() as $provider ) {
 624                         $info = $provider->provideSessionInfo( $request );
 625                         if ( !$info ) {
 626                                 continue;
 627                         }
 628                         if ( $info->getProvider() !== $provider ) {
 629                                 throw new \UnexpectedValueException(
 630                                         "$provider returned session info for a different provider: $info"
 631                                 );
 632                         }
 633                         $infos[] = $info;
 634                 }
 635
 636                 // Sort the SessionInfos. Then find the first one that can be
 637                 // successfully loaded, and then all the ones after it with the same
 638                 // priority.
 639                 usort( $infos, 'MediaWiki\\Session\\SessionInfo::compare' );
 640                 $retInfos = [];
 641                 while ( $infos ) {
 642                         $info = array_pop( $infos );
 643                         if ( $this->loadSessionInfoFromStore( $info, $request ) ) {
 644                                 $retInfos[] = $info;
 645                                 while ( $infos ) {
 646                                         $info = array_pop( $infos );
 647                                         if ( SessionInfo::compare( $retInfos[0], $info ) ) {
 648                                                 // We hit a lower priority, stop checking.
 649                                                 break;
 650                                         }
 651                                         if ( $this->loadSessionInfoFromStore( $info, $request ) ) {
 652                                                 // This is going to error out below, but we want to
 653                                                 // provide a complete list.
 654                                                 $retInfos[] = $info;
 655                                         }
 656                                 }
 657                         }
 658                 }
 659
 660                 if ( count( $retInfos ) > 1 ) {
 661                         $ex = new \OverflowException(
 662                                 'Multiple sessions for this request tied for top priority: ' . join( ', ', $retInfos )
 663                         );
 664                         $ex->sessionInfos = $retInfos;
 665                         throw $ex;
 666                 }
 667
 668                 return $retInfos ? $retInfos[0] : null;
 669         }
 670
 671         /**
 672          * Load and verify the session info against the store
 673          *
 674          * @param SessionInfo &$info Will likely be replaced with an updated SessionInfo instance
 675          * @param WebRequest $request
 676          * @return bool Whether the session info matches the stored data (if any)
 677          */
 678         private function loadSessionInfoFromStore( SessionInfo &$info, WebRequest $request ) {
 679                 $key = wfMemcKey( 'MWSession', $info->getId() );
 680                 $blob = $this->store->get( $key );
 681
 682                 $newParams = [];
 683
 684                 if ( $blob !== false ) {
 685                         // Sanity check: blob must be an array, if it's saved at all
 686                         if ( !is_array( $blob ) ) {
 687                                 $this->logger->warning( 'Session "{session}": Bad data', [
 688                                         'session' => $info,
 689                                 ] );
 690                                 $this->store->delete( $key );
 691                                 return false;
 692                         }
 693
 694                         // Sanity check: blob has data and metadata arrays
 695                         if ( !isset( $blob['data'] ) || !is_array( $blob['data'] ) ||
 696                                 !isset( $blob['metadata'] ) || !is_array( $blob['metadata'] )
 697                         ) {
 698                                 $this->logger->warning( 'Session "{session}": Bad data structure', [
 699                                         'session' => $info,
 700                                 ] );
 701                                 $this->store->delete( $key );
 702                                 return false;
 703                         }
 704
 705                         $data = $blob['data'];
 706                         $metadata = $blob['metadata'];
 707
 708                         // Sanity check: metadata must be an array and must contain certain
 709                         // keys, if it's saved at all
 710                         if ( !array_key_exists( 'userId', $metadata ) ||
 711                                 !array_key_exists( 'userName', $metadata ) ||
 712                                 !array_key_exists( 'userToken', $metadata ) ||
 713                                 !array_key_exists( 'provider', $metadata )
 714                         ) {
 715                                 $this->logger->warning( 'Session "{session}": Bad metadata', [
 716                                         'session' => $info,
 717                                 ] );
 718                                 $this->store->delete( $key );
 719                                 return false;
 720                         }
 721
 722                         // First, load the provider from metadata, or validate it against the metadata.
 723                         $provider = $info->getProvider();
 724                         if ( $provider === null ) {
 725                                 $newParams['provider'] = $provider = $this->getProvider( $metadata['provider'] );
 726                                 if ( !$provider ) {
 727                                         $this->logger->warning(
 728                                                 'Session "{session}": Unknown provider ' . $metadata['provider'],
 729                                                 [
 730                                                         'session' => $info,
 731                                                 ]
 732                                         );
 733                                         $this->store->delete( $key );
 734                                         return false;
 735                                 }
 736                         } elseif ( $metadata['provider'] !== (string)$provider ) {
 737                                 $this->logger->warning( 'Session "{session}": Wrong provider ' .
 738                                         $metadata['provider'] . ' !== ' . $provider,
 739                                         [
 740                                                 'session' => $info,
 741                                 ] );
 742                                 return false;
 743                         }
 744
 745                         // Load provider metadata from metadata, or validate it against the metadata
 746                         $providerMetadata = $info->getProviderMetadata();
 747                         if ( isset( $metadata['providerMetadata'] ) ) {
 748                                 if ( $providerMetadata === null ) {
 749                                         $newParams['metadata'] = $metadata['providerMetadata'];
 750                                 } else {
 751                                         try {
 752                                                 $newProviderMetadata = $provider->mergeMetadata(
 753                                                         $metadata['providerMetadata'], $providerMetadata
 754                                                 );
 755                                                 if ( $newProviderMetadata !== $providerMetadata ) {
 756                                                         $newParams['metadata'] = $newProviderMetadata;
 757                                                 }
 758                                         } catch ( MetadataMergeException $ex ) {
 759                                                 $this->logger->warning(
 760                                                         'Session "{session}": Metadata merge failed: {exception}',
 761                                                         [
 762                                                                 'session' => $info,
 763                                                                 'exception' => $ex,
 764                                                         ] + $ex->getContext()
 765                                                 );
 766                                                 return false;
 767                                         }
 768                                 }
 769                         }
 770
 771                         // Next, load the user from metadata, or validate it against the metadata.
 772                         $userInfo = $info->getUserInfo();
 773                         if ( !$userInfo ) {
 774                                 // For loading, id is preferred to name.
 775                                 try {
 776                                         if ( $metadata['userId'] ) {
 777                                                 $userInfo = UserInfo::newFromId( $metadata['userId'] );
 778                                         } elseif ( $metadata['userName'] !== null ) { // Shouldn't happen, but just in case
 779                                                 $userInfo = UserInfo::newFromName( $metadata['userName'] );
 780                                         } else {
 781                                                 $userInfo = UserInfo::newAnonymous();
 782                                         }
 783                                 } catch ( \InvalidArgumentException $ex ) {
 784                                         $this->logger->error( 'Session "{session}": {exception}', [
 785                                                 'session' => $info,
 786                                                 'exception' => $ex,
 787                                         ] );
 788                                         return false;
 789                                 }
 790                                 $newParams['userInfo'] = $userInfo;
 791                         } else {
 792                                 // User validation passes if user ID matches, or if there
 793                                 // is no saved ID and the names match.
 794                                 if ( $metadata['userId'] ) {
 795                                         if ( $metadata['userId'] !== $userInfo->getId() ) {
 796                                                 $this->logger->warning(
 797                                                         'Session "{session}": User ID mismatch, {uid_a} !== {uid_b}',
 798                                                         [
 799                                                                 'session' => $info,
 800                                                                 'uid_a' => $metadata['userId'],
 801                                                                 'uid_b' => $userInfo->getId(),
 802                                                 ] );
 803                                                 return false;
 804                                         }
 805
 806                                         // If the user was renamed, probably best to fail here.
 807                                         if ( $metadata['userName'] !== null &&
 808                                                 $userInfo->getName() !== $metadata['userName']
 809                                         ) {
 810                                                 $this->logger->warning(
 811                                                         'Session "{session}": User ID matched but name didn\'t (rename?), {uname_a} !== {uname_b}',
 812                                                         [
 813                                                                 'session' => $info,
 814                                                                 'uname_a' => $metadata['userName'],
 815                                                                 'uname_b' => $userInfo->getName(),
 816                                                 ] );
 817                                                 return false;
 818                                         }
 819
 820                                 } elseif ( $metadata['userName'] !== null ) { // Shouldn't happen, but just in case
 821                                         if ( $metadata['userName'] !== $userInfo->getName() ) {
 822                                                 $this->logger->warning(
 823                                                         'Session "{session}": User name mismatch, {uname_a} !== {uname_b}',
 824                                                         [
 825                                                                 'session' => $info,
 826                                                                 'uname_a' => $metadata['userName'],
 827                                                                 'uname_b' => $userInfo->getName(),
 828                                                 ] );
 829                                                 return false;
 830                                         }
 831                                 } elseif ( !$userInfo->isAnon() ) {
 832                                         // Metadata specifies an anonymous user, but the passed-in
 833                                         // user isn't anonymous.
 834                                         $this->logger->warning(
 835                                                 'Session "{session}": Metadata has an anonymous user, but a non-anon user was provided',
 836                                                 [
 837                                                         'session' => $info,
 838                                         ] );
 839                                         return false;
 840                                 }
 841                         }
 842
 843                         // And if we have a token in the metadata, it must match the loaded/provided user.
 844                         if ( $metadata['userToken'] !== null &&
 845                                 $userInfo->getToken() !== $metadata['userToken']
 846                         ) {
 847                                 $this->logger->warning( 'Session "{session}": User token mismatch', [
 848                                         'session' => $info,
 849                                 ] );
 850                                 return false;
 851                         }
 852                         if ( !$userInfo->isVerified() ) {
 853                                 $newParams['userInfo'] = $userInfo->verified();
 854                         }
 855
 856                         if ( !empty( $metadata['remember'] ) && !$info->wasRemembered() ) {
 857                                 $newParams['remembered'] = true;
 858                         }
 859                         if ( !empty( $metadata['forceHTTPS'] ) && !$info->forceHTTPS() ) {
 860                                 $newParams['forceHTTPS'] = true;
 861                         }
 862                         if ( !empty( $metadata['persisted'] ) && !$info->wasPersisted() ) {
 863                                 $newParams['persisted'] = true;
 864                         }
 865
 866                         if ( !$info->isIdSafe() ) {
 867                                 $newParams['idIsSafe'] = true;
 868                         }
 869                 } else {
 870                         // No metadata, so we can't load the provider if one wasn't given.
 871                         if ( $info->getProvider() === null ) {
 872                                 $this->logger->warning(
 873                                         'Session "{session}": Null provider and no metadata',
 874                                         [
 875                                                 'session' => $info,
 876                                 ] );
 877                                 return false;
 878                         }
 879
 880                         // If no user was provided and no metadata, it must be anon.
 881                         if ( !$info->getUserInfo() ) {
 882                                 if ( $info->getProvider()->canChangeUser() ) {
 883                                         $newParams['userInfo'] = UserInfo::newAnonymous();
 884                                 } else {
 885                                         $this->logger->info(
 886                                                 'Session "{session}": No user provided and provider cannot set user',
 887                                                 [
 888                                                         'session' => $info,
 889                                         ] );
 890                                         return false;
 891                                 }
 892                         } elseif ( !$info->getUserInfo()->isVerified() ) {
 893                                 $this->logger->warning(
 894                                         'Session "{session}": Unverified user provided and no metadata to auth it',
 895                                         [
 896                                                 'session' => $info,
 897                                 ] );
 898                                 return false;
 899                         }
 900
 901                         $data = false;
 902                         $metadata = false;
 903
 904                         if ( !$info->getProvider()->persistsSessionId() && !$info->isIdSafe() ) {
 905                                 // The ID doesn't come from the user, so it should be safe
 906                                 // (and if not, nothing we can do about it anyway)
 907                                 $newParams['idIsSafe'] = true;
 908                         }
 909                 }
 910
 911                 // Construct the replacement SessionInfo, if necessary
 912                 if ( $newParams ) {
 913                         $newParams['copyFrom'] = $info;
 914                         $info = new SessionInfo( $info->getPriority(), $newParams );
 915                 }
 916
 917                 // Allow the provider to check the loaded SessionInfo
 918                 $providerMetadata = $info->getProviderMetadata();
 919                 if ( !$info->getProvider()->refreshSessionInfo( $info, $request, $providerMetadata ) ) {
 920                         return false;
 921                 }
 922                 if ( $providerMetadata !== $info->getProviderMetadata() ) {
 923                         $info = new SessionInfo( $info->getPriority(), [
 924                                 'metadata' => $providerMetadata,
 925                                 'copyFrom' => $info,
 926                         ] );
 927                 }
 928
 929                 // Give hooks a chance to abort. Combined with the SessionMetadata
 930                 // hook, this can allow for tying a session to an IP address or the
 931                 // like.
 932                 $reason = 'Hook aborted';
 933                 if ( !\Hooks::run(
 934                         'SessionCheckInfo',
 935                         [ &$reason, $info, $request, $metadata, $data ]
 936                 ) ) {
 937                         $this->logger->warning( 'Session "{session}": ' . $reason, [
 938                                 'session' => $info,
 939                         ] );
 940                         return false;
 941                 }
 942
 943                 return true;
 944         }
 945
 946         /**
 947          * Create a session corresponding to the passed SessionInfo
 948          * @private For use by a SessionProvider that needs to specially create its
 949          *  own session.
 950          * @param SessionInfo $info
 951          * @param WebRequest $request
 952          * @return Session
 953          */
 954         public function getSessionFromInfo( SessionInfo $info, WebRequest $request ) {
 955                 $id = $info->getId();
 956
 957                 if ( !isset( $this->allSessionBackends[$id] ) ) {
 958                         if ( !isset( $this->allSessionIds[$id] ) ) {
 959                                 $this->allSessionIds[$id] = new SessionId( $id );
 960                         }
 961                         $backend = new SessionBackend(
 962                                 $this->allSessionIds[$id],
 963                                 $info,
 964                                 $this->store,
 965                                 $this->logger,
 966                                 $this->config->get( 'ObjectCacheSessionExpiry' )
 967                         );
 968                         $this->allSessionBackends[$id] = $backend;
 969                         $delay = $backend->delaySave();
 970                 } else {
 971                         $backend = $this->allSessionBackends[$id];
 972                         $delay = $backend->delaySave();
 973                         if ( $info->wasPersisted() ) {
 974                                 $backend->persist();
 975                         }
 976                         if ( $info->wasRemembered() ) {
 977                                 $backend->setRememberUser( true );
 978                         }
 979                 }
 980
 981                 $request->setSessionId( $backend->getSessionId() );
 982                 $session = $backend->getSession( $request );
 983
 984                 if ( !$info->isIdSafe() ) {
 985                         $session->resetId();
 986                 }
 987
 988                 \ScopedCallback::consume( $delay );
 989                 return $session;
 990         }
 991
 992         /**
 993          * Deregister a SessionBackend
 994          * @private For use from \\MediaWiki\\Session\\SessionBackend only
 995          * @param SessionBackend $backend
 996          */
 997         public function deregisterSessionBackend( SessionBackend $backend ) {
 998                 $id = $backend->getId();
 999                 if ( !isset( $this->allSessionBackends[$id] ) || !isset( $this->allSessionIds[$id] ) ||
1000                         $this->allSessionBackends[$id] !== $backend ||
1001                         $this->allSessionIds[$id] !== $backend->getSessionId()
1002                 ) {
1003                         throw new \InvalidArgumentException( 'Backend was not registered with this SessionManager' );
1004                 }
1005
1006                 unset( $this->allSessionBackends[$id] );
1007                 // Explicitly do not unset $this->allSessionIds[$id]
1008         }
1009
1010         /**
1011          * Change a SessionBackend's ID
1012          * @private For use from \\MediaWiki\\Session\\SessionBackend only
1013          * @param SessionBackend $backend
1014          */
1015         public function changeBackendId( SessionBackend $backend ) {
1016                 $sessionId = $backend->getSessionId();
1017                 $oldId = (string)$sessionId;
1018                 if ( !isset( $this->allSessionBackends[$oldId] ) || !isset( $this->allSessionIds[$oldId] ) ||
1019                         $this->allSessionBackends[$oldId] !== $backend ||
1020                         $this->allSessionIds[$oldId] !== $sessionId
1021                 ) {
1022                         throw new \InvalidArgumentException( 'Backend was not registered with this SessionManager' );
1023                 }
1024
1025                 $newId = $this->generateSessionId();
1026
1027                 unset( $this->allSessionBackends[$oldId], $this->allSessionIds[$oldId] );
1028                 $sessionId->setId( $newId );
1029                 $this->allSessionBackends[$newId] = $backend;
1030                 $this->allSessionIds[$newId] = $sessionId;
1031         }
1032
1033         /**
1034          * Generate a new random session ID
1035          * @return string
1036          */
1037         public function generateSessionId() {
1038                 do {
1039                         $id = wfBaseConvert( \MWCryptRand::generateHex( 40 ), 16, 32, 32 );
1040                         $key = wfMemcKey( 'MWSession', $id );
1041                 } while ( isset( $this->allSessionIds[$id] ) || is_array( $this->store->get( $key ) ) );
1042                 return $id;
1043         }
1044
1045         /**
1046          * Call setters on a PHPSessionHandler
1047          * @private Use PhpSessionHandler::install()
1048          * @param PHPSessionHandler $handler
1049          */
1050         public function setupPHPSessionHandler( PHPSessionHandler $handler ) {
1051                 $handler->setManager( $this, $this->store, $this->logger );
1052         }
1053
1054         /**
1055          * Reset the internal caching for unit testing
1056          */
1057         public static function resetCache() {
1058                 if ( !defined( 'MW_PHPUNIT_TEST' ) ) {
1059                         // @codeCoverageIgnoreStart
1060                         throw new MWException( __METHOD__ . ' may only be called from unit tests!' );
1061                         // @codeCoverageIgnoreEnd
1062                 }
1063
1064                 self::$globalSession = null;
1065                 self::$globalSessionRequest = null;
1066         }
1067
1068         /**
1069          * Do a sanity check to make sure the session is not used from many different IP addresses
1070          * and store some data for later sanity checks.
1071          * FIXME remove this once SessionManager is considered stable
1072          * @private For use in Setup.php only
1073          * @param Session $session Defaults to the global session.
1074          */
1075         public function checkIpLimits( Session $session = null ) {
1076                 $session = $session ?: self::getGlobalSession();
1077
1078                 try {
1079                         $ip = $session->getRequest()->getIP();
1080                 } catch ( \MWException $e ) {
1081                         return;
1082                 }
1083                 if ( $ip === '127.0.0.1' || \IP::isConfiguredProxy( $ip ) ) {
1084                         return;
1085                 }
1086                 $now = time();
1087
1088                 // Record (and possibly log) that the IP is using the current session.
1089                 // Don't touch the stored data unless we are adding a new IP or re-adding an expired one.
1090                 // This is slightly inaccurate (when an existing IP is seen again, the expiry is not
1091                 // extended) but that shouldn't make much difference and limits the session write frequency
1092                 // to # of IPs / $wgSuspiciousIpExpiry.
1093                 $data = $session->get( 'SessionManager-ip', [] );
1094                 if (
1095                         !isset( $data[$ip] )
1096                         || $data[$ip] < $now
1097                 ) {
1098                         $data[$ip] = time() + $this->config->get( 'SuspiciousIpExpiry' );
1099                         foreach ( $data as $key => $expires ) {
1100                                 if ( $expires < $now ) {
1101                                         unset( $data[$key] );
1102                                 }
1103                         }
1104                         $session->set( 'SessionManager-ip', $data );
1105
1106                         $logger = \MediaWiki\Logger\LoggerFactory::getInstance( 'session-ip' );
1107                         $logLevel = count( $data ) >= $this->config->get( 'SuspiciousIpPerSessionLimit' )
1108                                 ? LogLevel::WARNING : ( count( $data ) === 1 ? LogLevel::DEBUG : LogLevel::INFO );
1109                         $logger->log(
1110                                 $logLevel,
1111                                 'Same session used from {count} IPs',
1112                                 [
1113                                         'count' => count( $data ),
1114                                         'ips' => $data,
1115                                         'session' => $session->getId(),
1116                                         'user' => $session->getUser()->getName(),
1117                                         'persistent' => $session->isPersistent(),
1118                                 ]
1119                         );
1120                 }
1121
1122                 // Now do the same thing globally for the current user.
1123                 // We are using the object cache and assume it is shared between all wikis of a farm,
1124                 // and further assume that the same name belongs to the same user on all wikis. (It's either
1125                 // that or a central ID lookup which would mean an extra SQL query on every request.)
1126                 if ( $session->getUser()->isLoggedIn() ) {
1127                         $userKey = 'SessionManager-ip:' . md5( $session->getUser()->getName() );
1128                         $data = $this->store->get( $userKey ) ?: [];
1129                         if (
1130                                 !isset( $data[$ip] )
1131                                 || $data[$ip] < $now
1132                         ) {
1133                                 $data[$ip] = time() + $this->config->get( 'SuspiciousIpExpiry' );
1134                                 foreach ( $data as $key => $expires ) {
1135                                         if ( $expires < $now ) {
1136                                                 unset( $data[$key] );
1137                                         }
1138                                 }
1139                                 $this->store->set( $userKey, $data, $this->config->get( 'SuspiciousIpExpiry' ) );
1140                                 $logger = \MediaWiki\Logger\LoggerFactory::getInstance( 'session-ip' );
1141                                 $logLevel = count( $data ) >= $this->config->get( 'SuspiciousIpPerUserLimit' )
1142                                         ? LogLevel::WARNING : ( count( $data ) === 1 ? LogLevel::DEBUG : LogLevel::INFO );
1143                                 $logger->log(
1144                                         $logLevel,
1145                                         'Same user had sessions from {count} IPs',
1146                                         [
1147                                                 'count' => count( $data ),
1148                                                 'ips' => $data,
1149                                                 'session' => $session->getId(),
1150                                                 'user' => $session->getUser()->getName(),
1151                                                 'persistent' => $session->isPersistent(),
1152                                         ]
1153                                 );
1154                         }
1155                 }
1156         }
1157
1158         /**@}*/
1159
1160 }