includes/block/BlockManager.php

   1 <?php
   2 /**
   3  * This program is free software; you can redistribute it and/or modify
   4  * it under the terms of the GNU General Public License as published by
   5  * the Free Software Foundation; either version 2 of the License, or
   6  * (at your option) any later version.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along
  14  * with this program; if not, write to the Free Software Foundation, Inc.,
  15  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  16  * http://www.gnu.org/copyleft/gpl.html
  17  *
  18  * @file
  19  */
  20
  21 namespace MediaWiki\Block;
  22
  23 use DateTime;
  24 use DateTimeZone;
  25 use DeferredUpdates;
  26 use Hooks;
  27 use IP;
  28 use MediaWiki\Config\ServiceOptions;
  29 use MediaWiki\Permissions\PermissionManager;
  30 use MediaWiki\User\UserIdentity;
  31 use MWCryptHash;
  32 use User;
  33 use WebRequest;
  34 use WebResponse;
  35 use Wikimedia\IPSet;
  36
  37 /**
  38  * A service class for checking blocks.
  39  * To obtain an instance, use MediaWikiServices::getInstance()->getBlockManager().
  40  *
  41  * @since 1.34 Refactored from User and Block.
  42  */
  43 class BlockManager {
  44         // TODO: This should be UserIdentity instead of User
  45         /** @var User */
  46         private $currentUser;
  47
  48         /** @var WebRequest */
  49         private $currentRequest;
  50
  51         /** @var PermissionManager */
  52         private $permissionManager;
  53
  54         /**
  55          * TODO Make this a const when HHVM support is dropped (T192166)
  56          *
  57          * @var array
  58          * @since 1.34
  59          */
  60         public static $constructorOptions = [
  61                 'ApplyIpBlocksToXff',
  62                 'CookieSetOnAutoblock',
  63                 'CookieSetOnIpBlock',
  64                 'DnsBlacklistUrls',
  65                 'EnableDnsBlacklist',
  66                 'ProxyList',
  67                 'ProxyWhitelist',
  68                 'SecretKey',
  69                 'SoftBlockRanges',
  70         ];
  71
  72         /**
  73          * @param ServiceOptions $options
  74          * @param User $currentUser
  75          * @param WebRequest $currentRequest
  76          * @param PermissionManager $permissionManager
  77          */
  78         public function __construct(
  79                 ServiceOptions $options,
  80                 User $currentUser,
  81                 WebRequest $currentRequest,
  82                 PermissionManager $permissionManager
  83         ) {
  84                 $options->assertRequiredOptions( self::$constructorOptions );
  85                 $this->options = $options;
  86                 $this->currentUser = $currentUser;
  87                 $this->currentRequest = $currentRequest;
  88                 $this->permissionManager = $permissionManager;
  89         }
  90
  91         /**
  92          * Get the blocks that apply to a user. If there is only one, return that, otherwise
  93          * return a composite block that combines the strictest features of the applicable
  94          * blocks.
  95          *
  96          * TODO: $user should be UserIdentity instead of User
  97          *
  98          * @internal This should only be called by User::getBlockedStatus
  99          * @param User $user
 100          * @param bool $fromReplica Whether to check the replica DB first.
 101          *  To improve performance, non-critical checks are done against replica DBs.
 102          *  Check when actually saving should be done against master.
 103          * @return AbstractBlock|null The most relevant block, or null if there is no block.
 104          */
 105         public function getUserBlock( User $user, $fromReplica ) {
 106                 $isAnon = $user->getId() === 0;
 107                 $fromMaster = !$fromReplica;
 108
 109                 // TODO: If $user is the current user, we should use the current request. Otherwise,
 110                 // we should not look for XFF or cookie blocks.
 111                 $request = $user->getRequest();
 112
 113                 # We only need to worry about passing the IP address to the block generator if the
 114                 # user is not immune to autoblocks/hardblocks, and they are the current user so we
 115                 # know which IP address they're actually coming from
 116                 $ip = null;
 117                 $sessionUser = $this->currentUser;
 118                 // the session user is set up towards the end of Setup.php. Until then,
 119                 // assume it's a logged-out user.
 120                 $globalUserName = $sessionUser->isSafeToLoad()
 121                         ? $sessionUser->getName()
 122                         : IP::sanitizeIP( $this->currentRequest->getIP() );
 123                 if ( $user->getName() === $globalUserName &&
 124                          !$this->permissionManager->userHasRight( $user, 'ipblock-exempt' ) ) {
 125                         $ip = $this->currentRequest->getIP();
 126                 }
 127
 128                 // User/IP blocking
 129                 // After this, $blocks is an array of blocks or an empty array
 130                 // TODO: remove dependency on DatabaseBlock
 131                 $blocks = DatabaseBlock::newListFromTarget( $user, $ip, $fromMaster );
 132
 133                 // Cookie blocking
 134                 $cookieBlock = $this->getBlockFromCookieValue( $user, $request );
 135                 if ( $cookieBlock instanceof AbstractBlock ) {
 136                         $blocks[] = $cookieBlock;
 137                 }
 138
 139                 // Proxy blocking
 140                 if ( $ip !== null && !in_array( $ip, $this->options->get( 'ProxyWhitelist' ) ) ) {
 141                         // Local list
 142                         if ( $this->isLocallyBlockedProxy( $ip ) ) {
 143                                 $blocks[] = new SystemBlock( [
 144                                         'byText' => wfMessage( 'proxyblocker' )->text(),
 145                                         'reason' => wfMessage( 'proxyblockreason' )->plain(),
 146                                         'address' => $ip,
 147                                         'systemBlock' => 'proxy',
 148                                 ] );
 149                         } elseif ( $isAnon && $this->isDnsBlacklisted( $ip ) ) {
 150                                 $blocks[] = new SystemBlock( [
 151                                         'byText' => wfMessage( 'sorbs' )->text(),
 152                                         'reason' => wfMessage( 'sorbsreason' )->plain(),
 153                                         'address' => $ip,
 154                                         'systemBlock' => 'dnsbl',
 155                                 ] );
 156                         }
 157                 }
 158
 159                 // (T25343) Apply IP blocks to the contents of XFF headers, if enabled
 160                 if ( $this->options->get( 'ApplyIpBlocksToXff' )
 161                         && $ip !== null
 162                         && !in_array( $ip, $this->options->get( 'ProxyWhitelist' ) )
 163                 ) {
 164                         $xff = $request->getHeader( 'X-Forwarded-For' );
 165                         $xff = array_map( 'trim', explode( ',', $xff ) );
 166                         $xff = array_diff( $xff, [ $ip ] );
 167                         // TODO: remove dependency on DatabaseBlock
 168                         $xffblocks = DatabaseBlock::getBlocksForIPList( $xff, $isAnon, $fromMaster );
 169                         $blocks = array_merge( $blocks, $xffblocks );
 170                 }
 171
 172                 // Soft blocking
 173                 if ( $ip !== null
 174                         && $isAnon
 175                         && IP::isInRanges( $ip, $this->options->get( 'SoftBlockRanges' ) )
 176                 ) {
 177                         $blocks[] = new SystemBlock( [
 178                                 'address' => $ip,
 179                                 'byText' => 'MediaWiki default',
 180                                 'reason' => wfMessage( 'softblockrangesreason', $ip )->plain(),
 181                                 'anonOnly' => true,
 182                                 'systemBlock' => 'wgSoftBlockRanges',
 183                         ] );
 184                 }
 185
 186                 // Filter out any duplicated blocks, e.g. from the cookie
 187                 $blocks = $this->getUniqueBlocks( $blocks );
 188
 189                 $block = null;
 190                 if ( count( $blocks ) > 0 ) {
 191                         if ( count( $blocks ) === 1 ) {
 192                                 $block = $blocks[ 0 ];
 193                         } else {
 194                                 $block = new CompositeBlock( [
 195                                         'address' => $ip,
 196                                         'byText' => 'MediaWiki default',
 197                                         'reason' => wfMessage( 'blockedtext-composite-reason' )->plain(),
 198                                         'originalBlocks' => $blocks,
 199                                 ] );
 200                         }
 201                 }
 202
 203                 Hooks::run( 'GetUserBlock', [ clone $user, $ip, &$block ] );
 204
 205                 return $block;
 206         }
 207
 208         /**
 209          * Given a list of blocks, return a list of unique blocks.
 210          *
 211          * This usually means that each block has a unique ID. For a block with ID null,
 212          * if it's an autoblock, it will be filtered out if the parent block is present;
 213          * if not, it is assumed to be a unique system block, and kept.
 214          *
 215          * @param AbstractBlock[] $blocks
 216          * @return AbstractBlock[]
 217          */
 218         private function getUniqueBlocks( array $blocks ) {
 219                 $systemBlocks = [];
 220                 $databaseBlocks = [];
 221
 222                 foreach ( $blocks as $block ) {
 223                         if ( $block instanceof SystemBlock ) {
 224                                 $systemBlocks[] = $block;
 225                         } elseif ( $block->getType() === DatabaseBlock::TYPE_AUTO ) {
 226                                 /** @var DatabaseBlock $block */
 227                                 '@phan-var DatabaseBlock $block';
 228                                 if ( !isset( $databaseBlocks[$block->getParentBlockId()] ) ) {
 229                                         $databaseBlocks[$block->getParentBlockId()] = $block;
 230                                 }
 231                         } else {
 232                                 $databaseBlocks[$block->getId()] = $block;
 233                         }
 234                 }
 235
 236                 return array_values( array_merge( $systemBlocks, $databaseBlocks ) );
 237         }
 238
 239         /**
 240          * Try to load a block from an ID given in a cookie value. If the block is invalid
 241          * doesn't exist, or the cookie value is malformed, remove the cookie.
 242          *
 243          * @param UserIdentity $user
 244          * @param WebRequest $request
 245          * @return DatabaseBlock|bool The block object, or false if none could be loaded.
 246          */
 247         private function getBlockFromCookieValue(
 248                 UserIdentity $user,
 249                 WebRequest $request
 250         ) {
 251                 $cookieValue = $request->getCookie( 'BlockID' );
 252                 if ( is_null( $cookieValue ) ) {
 253                         return false;
 254                 }
 255
 256                 $blockCookieId = $this->getIdFromCookieValue( $cookieValue );
 257                 if ( !is_null( $blockCookieId ) ) {
 258                         // TODO: remove dependency on DatabaseBlock
 259                         $block = DatabaseBlock::newFromID( $blockCookieId );
 260                         if (
 261                                 $block instanceof DatabaseBlock &&
 262                                 $this->shouldApplyCookieBlock( $block, !$user->isRegistered() )
 263                         ) {
 264                                 return $block;
 265                         }
 266                 }
 267
 268                 $this->clearBlockCookie( $request->response() );
 269
 270                 return false;
 271         }
 272
 273         /**
 274          * Check if the block loaded from the cookie should be applied.
 275          *
 276          * @param DatabaseBlock $block
 277          * @param bool $isAnon The user is logged out
 278          * @return bool The block sould be applied
 279          */
 280         private function shouldApplyCookieBlock( DatabaseBlock $block, $isAnon ) {
 281                 if ( !$block->isExpired() ) {
 282                         switch ( $block->getType() ) {
 283                                 case DatabaseBlock::TYPE_IP:
 284                                 case DatabaseBlock::TYPE_RANGE:
 285                                         // If block is type IP or IP range, load only
 286                                         // if user is not logged in (T152462)
 287                                         return $isAnon &&
 288                                                 $this->options->get( 'CookieSetOnIpBlock' );
 289                                 case DatabaseBlock::TYPE_USER:
 290                                         return $block->isAutoblocking() &&
 291                                                 $this->options->get( 'CookieSetOnAutoblock' );
 292                                 default:
 293                                         return false;
 294                         }
 295                 }
 296                 return false;
 297         }
 298
 299         /**
 300          * Check if an IP address is in the local proxy list
 301          *
 302          * @param string $ip
 303          * @return bool
 304          */
 305         private function isLocallyBlockedProxy( $ip ) {
 306                 $proxyList = $this->options->get( 'ProxyList' );
 307                 if ( !$proxyList ) {
 308                         return false;
 309                 }
 310
 311                 if ( !is_array( $proxyList ) ) {
 312                         // Load values from the specified file
 313                         $proxyList = array_map( 'trim', file( $proxyList ) );
 314                 }
 315
 316                 $proxyListIPSet = new IPSet( $proxyList );
 317                 return $proxyListIPSet->match( $ip );
 318         }
 319
 320         /**
 321          * Whether the given IP is in a DNS blacklist.
 322          *
 323          * @param string $ip IP to check
 324          * @param bool $checkWhitelist Whether to check the whitelist first
 325          * @return bool True if blacklisted.
 326          */
 327         public function isDnsBlacklisted( $ip, $checkWhitelist = false ) {
 328                 if ( !$this->options->get( 'EnableDnsBlacklist' ) ||
 329                         ( $checkWhitelist && in_array( $ip, $this->options->get( 'ProxyWhitelist' ) ) )
 330                 ) {
 331                         return false;
 332                 }
 333
 334                 return $this->inDnsBlacklist( $ip, $this->options->get( 'DnsBlacklistUrls' ) );
 335         }
 336
 337         /**
 338          * Whether the given IP is in a given DNS blacklist.
 339          *
 340          * @param string $ip IP to check
 341          * @param array $bases Array of Strings: URL of the DNS blacklist
 342          * @return bool True if blacklisted.
 343          */
 344         private function inDnsBlacklist( $ip, array $bases ) {
 345                 $found = false;
 346                 // @todo FIXME: IPv6 ???  (https://bugs.php.net/bug.php?id=33170)
 347                 if ( IP::isIPv4( $ip ) ) {
 348                         // Reverse IP, T23255
 349                         $ipReversed = implode( '.', array_reverse( explode( '.', $ip ) ) );
 350
 351                         foreach ( $bases as $base ) {
 352                                 // Make hostname
 353                                 // If we have an access key, use that too (ProjectHoneypot, etc.)
 354                                 $basename = $base;
 355                                 if ( is_array( $base ) ) {
 356                                         if ( count( $base ) >= 2 ) {
 357                                                 // Access key is 1, base URL is 0
 358                                                 $hostname = "{$base[1]}.$ipReversed.{$base[0]}";
 359                                         } else {
 360                                                 $hostname = "$ipReversed.{$base[0]}";
 361                                         }
 362                                         $basename = $base[0];
 363                                 } else {
 364                                         $hostname = "$ipReversed.$base";
 365                                 }
 366
 367                                 // Send query
 368                                 $ipList = $this->checkHost( $hostname );
 369
 370                                 if ( $ipList ) {
 371                                         wfDebugLog(
 372                                                 'dnsblacklist',
 373                                                 "Hostname $hostname is {$ipList[0]}, it's a proxy says $basename!"
 374                                         );
 375                                         $found = true;
 376                                         break;
 377                                 }
 378
 379                                 wfDebugLog( 'dnsblacklist', "Requested $hostname, not found in $basename." );
 380                         }
 381                 }
 382
 383                 return $found;
 384         }
 385
 386         /**
 387          * Wrapper for mocking in tests.
 388          *
 389          * @param string $hostname DNSBL query
 390          * @return string[]|bool IPv4 array, or false if the IP is not blacklisted
 391          */
 392         protected function checkHost( $hostname ) {
 393                 return gethostbynamel( $hostname );
 394         }
 395
 396         /**
 397          * Set the 'BlockID' cookie depending on block type and user authentication status.
 398          *
 399          * @since 1.34
 400          * @param User $user
 401          */
 402         public function trackBlockWithCookie( User $user ) {
 403                 $request = $user->getRequest();
 404                 if ( $request->getCookie( 'BlockID' ) !== null ) {
 405                         // User already has a block cookie
 406                         return;
 407                 }
 408
 409                 // Defer checks until the user has been fully loaded to avoid circular dependency
 410                 // of User on itself (T180050 and T226777)
 411                 DeferredUpdates::addCallableUpdate(
 412                         function () use ( $user, $request ) {
 413                                 $block = $user->getBlock();
 414                                 $response = $request->response();
 415                                 $isAnon = $user->isAnon();
 416
 417                                 if ( $block ) {
 418                                         if ( $block instanceof CompositeBlock ) {
 419                                                 // TODO: Improve on simply tracking the first trackable block (T225654)
 420                                                 foreach ( $block->getOriginalBlocks() as $originalBlock ) {
 421                                                         if ( $this->shouldTrackBlockWithCookie( $originalBlock, $isAnon ) ) {
 422                                                                 $this->setBlockCookie( $originalBlock, $response );
 423                                                                 return;
 424                                                         }
 425                                                 }
 426                                         } else {
 427                                                 if ( $this->shouldTrackBlockWithCookie( $block, $isAnon ) ) {
 428                                                         $this->setBlockCookie( $block, $response );
 429                                                 }
 430                                         }
 431                                 }
 432                         },
 433                         DeferredUpdates::PRESEND
 434                 );
 435         }
 436
 437         /**
 438          * Set the 'BlockID' cookie to this block's ID and expiry time. The cookie's expiry will be
 439          * the same as the block's, to a maximum of 24 hours.
 440          *
 441          * @since 1.34
 442          * @internal Should be private.
 443          *  Left public for backwards compatibility, until DatabaseBlock::setCookie is removed.
 444          * @param DatabaseBlock $block
 445          * @param WebResponse $response The response on which to set the cookie.
 446          */
 447         public function setBlockCookie( DatabaseBlock $block, WebResponse $response ) {
 448                 // Calculate the default expiry time.
 449                 $maxExpiryTime = wfTimestamp( TS_MW, wfTimestamp() + ( 24 * 60 * 60 ) );
 450
 451                 // Use the block's expiry time only if it's less than the default.
 452                 $expiryTime = $block->getExpiry();
 453                 if ( $expiryTime === 'infinity' || $expiryTime > $maxExpiryTime ) {
 454                         $expiryTime = $maxExpiryTime;
 455                 }
 456
 457                 // Set the cookie. Reformat the MediaWiki datetime as a Unix timestamp for the cookie.
 458                 $expiryValue = DateTime::createFromFormat(
 459                         'YmdHis',
 460                         $expiryTime,
 461                         new DateTimeZone( 'UTC' )
 462                 )->format( 'U' );
 463                 $cookieOptions = [ 'httpOnly' => false ];
 464                 $cookieValue = $this->getCookieValue( $block );
 465                 $response->setCookie( 'BlockID', $cookieValue, $expiryValue, $cookieOptions );
 466         }
 467
 468         /**
 469          * Check if the block should be tracked with a cookie.
 470          *
 471          * @param AbstractBlock $block
 472          * @param bool $isAnon The user is logged out
 473          * @return bool The block sould be tracked with a cookie
 474          */
 475         private function shouldTrackBlockWithCookie( AbstractBlock $block, $isAnon ) {
 476                 if ( $block instanceof DatabaseBlock ) {
 477                         switch ( $block->getType() ) {
 478                                 case DatabaseBlock::TYPE_IP:
 479                                 case DatabaseBlock::TYPE_RANGE:
 480                                         return $isAnon && $this->options->get( 'CookieSetOnIpBlock' );
 481                                 case DatabaseBlock::TYPE_USER:
 482                                         return !$isAnon &&
 483                                                 $this->options->get( 'CookieSetOnAutoblock' ) &&
 484                                                 $block->isAutoblocking();
 485                                 default:
 486                                         return false;
 487                         }
 488                 }
 489                 return false;
 490         }
 491
 492         /**
 493          * Unset the 'BlockID' cookie.
 494          *
 495          * @since 1.34
 496          * @param WebResponse $response
 497          */
 498         public static function clearBlockCookie( WebResponse $response ) {
 499                 $response->clearCookie( 'BlockID', [ 'httpOnly' => false ] );
 500         }
 501
 502         /**
 503          * Get the stored ID from the 'BlockID' cookie. The cookie's value is usually a combination of
 504          * the ID and a HMAC (see DatabaseBlock::setCookie), but will sometimes only be the ID.
 505          *
 506          * @since 1.34
 507          * @internal Should be private.
 508          *  Left public for backwards compatibility, until DatabaseBlock::getIdFromCookieValue is removed.
 509          * @param string $cookieValue The string in which to find the ID.
 510          * @return int|null The block ID, or null if the HMAC is present and invalid.
 511          */
 512         public function getIdFromCookieValue( $cookieValue ) {
 513                 // The cookie value must start with a number
 514                 if ( !is_numeric( substr( $cookieValue, 0, 1 ) ) ) {
 515                         return null;
 516                 }
 517
 518                 // Extract the ID prefix from the cookie value (may be the whole value, if no bang found).
 519                 $bangPos = strpos( $cookieValue, '!' );
 520                 $id = ( $bangPos === false ) ? $cookieValue : substr( $cookieValue, 0, $bangPos );
 521                 if ( !$this->options->get( 'SecretKey' ) ) {
 522                         // If there's no secret key, just use the ID as given.
 523                         return $id;
 524                 }
 525                 $storedHmac = substr( $cookieValue, $bangPos + 1 );
 526                 $calculatedHmac = MWCryptHash::hmac( $id, $this->options->get( 'SecretKey' ), false );
 527                 if ( $calculatedHmac === $storedHmac ) {
 528                         return $id;
 529                 } else {
 530                         return null;
 531                 }
 532         }
 533
 534         /**
 535          * Get the BlockID cookie's value for this block. This is usually the block ID concatenated
 536          * with an HMAC in order to avoid spoofing (T152951), but if wgSecretKey is not set will just
 537          * be the block ID.
 538          *
 539          * @since 1.34
 540          * @internal Should be private.
 541          *  Left public for backwards compatibility, until DatabaseBlock::getCookieValue is removed.
 542          * @param DatabaseBlock $block
 543          * @return string The block ID, probably concatenated with "!" and the HMAC.
 544          */
 545         public function getCookieValue( DatabaseBlock $block ) {
 546                 $id = $block->getId();
 547                 if ( !$this->options->get( 'SecretKey' ) ) {
 548                         // If there's no secret key, don't append a HMAC.
 549                         return $id;
 550                 }
 551                 $hmac = MWCryptHash::hmac( $id, $this->options->get( 'SecretKey' ), false );
 552                 $cookieValue = $id . '!' . $hmac;
 553                 return $cookieValue;
 554         }
 555
 556 }