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                                 if ( !isset( $databaseBlocks[$block->getParentBlockId()] ) ) {
 227                                         $databaseBlocks[$block->getParentBlockId()] = $block;
 228                                 }
 229                         } else {
 230                                 $databaseBlocks[$block->getId()] = $block;
 231                         }
 232                 }
 233
 234                 return array_values( array_merge( $systemBlocks, $databaseBlocks ) );
 235         }
 236
 237         /**
 238          * Try to load a block from an ID given in a cookie value. If the block is invalid
 239          * doesn't exist, or the cookie value is malformed, remove the cookie.
 240          *
 241          * @param UserIdentity $user
 242          * @param WebRequest $request
 243          * @return DatabaseBlock|bool The block object, or false if none could be loaded.
 244          */
 245         private function getBlockFromCookieValue(
 246                 UserIdentity $user,
 247                 WebRequest $request
 248         ) {
 249                 $cookieValue = $request->getCookie( 'BlockID' );
 250                 if ( is_null( $cookieValue ) ) {
 251                         return false;
 252                 }
 253
 254                 $blockCookieId = $this->getIdFromCookieValue( $cookieValue );
 255                 if ( !is_null( $blockCookieId ) ) {
 256                         // TODO: remove dependency on DatabaseBlock
 257                         $block = DatabaseBlock::newFromID( $blockCookieId );
 258                         if (
 259                                 $block instanceof DatabaseBlock &&
 260                                 $this->shouldApplyCookieBlock( $block, !$user->isRegistered() )
 261                         ) {
 262                                 return $block;
 263                         }
 264                 }
 265
 266                 $this->clearBlockCookie( $request->response() );
 267
 268                 return false;
 269         }
 270
 271         /**
 272          * Check if the block loaded from the cookie should be applied.
 273          *
 274          * @param DatabaseBlock $block
 275          * @param bool $isAnon The user is logged out
 276          * @return bool The block sould be applied
 277          */
 278         private function shouldApplyCookieBlock( DatabaseBlock $block, $isAnon ) {
 279                 if ( !$block->isExpired() ) {
 280                         switch ( $block->getType() ) {
 281                                 case DatabaseBlock::TYPE_IP:
 282                                 case DatabaseBlock::TYPE_RANGE:
 283                                         // If block is type IP or IP range, load only
 284                                         // if user is not logged in (T152462)
 285                                         return $isAnon &&
 286                                                 $this->options->get( 'CookieSetOnIpBlock' );
 287                                 case DatabaseBlock::TYPE_USER:
 288                                         return $block->isAutoblocking() &&
 289                                                 $this->options->get( 'CookieSetOnAutoblock' );
 290                                 default:
 291                                         return false;
 292                         }
 293                 }
 294                 return false;
 295         }
 296
 297         /**
 298          * Check if an IP address is in the local proxy list
 299          *
 300          * @param string $ip
 301          * @return bool
 302          */
 303         private function isLocallyBlockedProxy( $ip ) {
 304                 $proxyList = $this->options->get( 'ProxyList' );
 305                 if ( !$proxyList ) {
 306                         return false;
 307                 }
 308
 309                 if ( !is_array( $proxyList ) ) {
 310                         // Load values from the specified file
 311                         $proxyList = array_map( 'trim', file( $proxyList ) );
 312                 }
 313
 314                 $proxyListIPSet = new IPSet( $proxyList );
 315                 return $proxyListIPSet->match( $ip );
 316         }
 317
 318         /**
 319          * Whether the given IP is in a DNS blacklist.
 320          *
 321          * @param string $ip IP to check
 322          * @param bool $checkWhitelist Whether to check the whitelist first
 323          * @return bool True if blacklisted.
 324          */
 325         public function isDnsBlacklisted( $ip, $checkWhitelist = false ) {
 326                 if ( !$this->options->get( 'EnableDnsBlacklist' ) ||
 327                         ( $checkWhitelist && in_array( $ip, $this->options->get( 'ProxyWhitelist' ) ) )
 328                 ) {
 329                         return false;
 330                 }
 331
 332                 return $this->inDnsBlacklist( $ip, $this->options->get( 'DnsBlacklistUrls' ) );
 333         }
 334
 335         /**
 336          * Whether the given IP is in a given DNS blacklist.
 337          *
 338          * @param string $ip IP to check
 339          * @param array $bases Array of Strings: URL of the DNS blacklist
 340          * @return bool True if blacklisted.
 341          */
 342         private function inDnsBlacklist( $ip, array $bases ) {
 343                 $found = false;
 344                 // @todo FIXME: IPv6 ???  (https://bugs.php.net/bug.php?id=33170)
 345                 if ( IP::isIPv4( $ip ) ) {
 346                         // Reverse IP, T23255
 347                         $ipReversed = implode( '.', array_reverse( explode( '.', $ip ) ) );
 348
 349                         foreach ( $bases as $base ) {
 350                                 // Make hostname
 351                                 // If we have an access key, use that too (ProjectHoneypot, etc.)
 352                                 $basename = $base;
 353                                 if ( is_array( $base ) ) {
 354                                         if ( count( $base ) >= 2 ) {
 355                                                 // Access key is 1, base URL is 0
 356                                                 $hostname = "{$base[1]}.$ipReversed.{$base[0]}";
 357                                         } else {
 358                                                 $hostname = "$ipReversed.{$base[0]}";
 359                                         }
 360                                         $basename = $base[0];
 361                                 } else {
 362                                         $hostname = "$ipReversed.$base";
 363                                 }
 364
 365                                 // Send query
 366                                 $ipList = $this->checkHost( $hostname );
 367
 368                                 if ( $ipList ) {
 369                                         wfDebugLog(
 370                                                 'dnsblacklist',
 371                                                 "Hostname $hostname is {$ipList[0]}, it's a proxy says $basename!"
 372                                         );
 373                                         $found = true;
 374                                         break;
 375                                 }
 376
 377                                 wfDebugLog( 'dnsblacklist', "Requested $hostname, not found in $basename." );
 378                         }
 379                 }
 380
 381                 return $found;
 382         }
 383
 384         /**
 385          * Wrapper for mocking in tests.
 386          *
 387          * @param string $hostname DNSBL query
 388          * @return string[]|bool IPv4 array, or false if the IP is not blacklisted
 389          */
 390         protected function checkHost( $hostname ) {
 391                 return gethostbynamel( $hostname );
 392         }
 393
 394         /**
 395          * Set the 'BlockID' cookie depending on block type and user authentication status.
 396          *
 397          * @since 1.34
 398          * @param User $user
 399          */
 400         public function trackBlockWithCookie( User $user ) {
 401                 $request = $user->getRequest();
 402                 if ( $request->getCookie( 'BlockID' ) !== null ) {
 403                         // User already has a block cookie
 404                         return;
 405                 }
 406
 407                 // Defer checks until the user has been fully loaded to avoid circular dependency
 408                 // of User on itself (T180050 and T226777)
 409                 DeferredUpdates::addCallableUpdate(
 410                         function () use ( $user, $request ) {
 411                                 $block = $user->getBlock();
 412                                 $response = $request->response();
 413                                 $isAnon = $user->isAnon();
 414
 415                                 if ( $block ) {
 416                                         if ( $block instanceof CompositeBlock ) {
 417                                                 // TODO: Improve on simply tracking the first trackable block (T225654)
 418                                                 foreach ( $block->getOriginalBlocks() as $originalBlock ) {
 419                                                         if ( $this->shouldTrackBlockWithCookie( $originalBlock, $isAnon ) ) {
 420                                                                 $this->setBlockCookie( $originalBlock, $response );
 421                                                                 return;
 422                                                         }
 423                                                 }
 424                                         } else {
 425                                                 if ( $this->shouldTrackBlockWithCookie( $block, $isAnon ) ) {
 426                                                         $this->setBlockCookie( $block, $response );
 427                                                 }
 428                                         }
 429                                 }
 430                         },
 431                         DeferredUpdates::PRESEND
 432                 );
 433         }
 434
 435         /**
 436          * Set the 'BlockID' cookie to this block's ID and expiry time. The cookie's expiry will be
 437          * the same as the block's, to a maximum of 24 hours.
 438          *
 439          * @since 1.34
 440          * @internal Should be private.
 441          *  Left public for backwards compatibility, until DatabaseBlock::setCookie is removed.
 442          * @param DatabaseBlock $block
 443          * @param WebResponse $response The response on which to set the cookie.
 444          */
 445         public function setBlockCookie( DatabaseBlock $block, WebResponse $response ) {
 446                 // Calculate the default expiry time.
 447                 $maxExpiryTime = wfTimestamp( TS_MW, wfTimestamp() + ( 24 * 60 * 60 ) );
 448
 449                 // Use the block's expiry time only if it's less than the default.
 450                 $expiryTime = $block->getExpiry();
 451                 if ( $expiryTime === 'infinity' || $expiryTime > $maxExpiryTime ) {
 452                         $expiryTime = $maxExpiryTime;
 453                 }
 454
 455                 // Set the cookie. Reformat the MediaWiki datetime as a Unix timestamp for the cookie.
 456                 $expiryValue = DateTime::createFromFormat(
 457                         'YmdHis',
 458                         $expiryTime,
 459                         new DateTimeZone( 'UTC' )
 460                 )->format( 'U' );
 461                 $cookieOptions = [ 'httpOnly' => false ];
 462                 $cookieValue = $this->getCookieValue( $block );
 463                 $response->setCookie( 'BlockID', $cookieValue, $expiryValue, $cookieOptions );
 464         }
 465
 466         /**
 467          * Check if the block should be tracked with a cookie.
 468          *
 469          * @param AbstractBlock $block
 470          * @param bool $isAnon The user is logged out
 471          * @return bool The block sould be tracked with a cookie
 472          */
 473         private function shouldTrackBlockWithCookie( AbstractBlock $block, $isAnon ) {
 474                 if ( $block instanceof DatabaseBlock ) {
 475                         switch ( $block->getType() ) {
 476                                 case DatabaseBlock::TYPE_IP:
 477                                 case DatabaseBlock::TYPE_RANGE:
 478                                         return $isAnon && $this->options->get( 'CookieSetOnIpBlock' );
 479                                 case DatabaseBlock::TYPE_USER:
 480                                         return !$isAnon &&
 481                                                 $this->options->get( 'CookieSetOnAutoblock' ) &&
 482                                                 $block->isAutoblocking();
 483                                 default:
 484                                         return false;
 485                         }
 486                 }
 487                 return false;
 488         }
 489
 490         /**
 491          * Unset the 'BlockID' cookie.
 492          *
 493          * @since 1.34
 494          * @param WebResponse $response
 495          */
 496         public static function clearBlockCookie( WebResponse $response ) {
 497                 $response->clearCookie( 'BlockID', [ 'httpOnly' => false ] );
 498         }
 499
 500         /**
 501          * Get the stored ID from the 'BlockID' cookie. The cookie's value is usually a combination of
 502          * the ID and a HMAC (see DatabaseBlock::setCookie), but will sometimes only be the ID.
 503          *
 504          * @since 1.34
 505          * @internal Should be private.
 506          *  Left public for backwards compatibility, until DatabaseBlock::getIdFromCookieValue is removed.
 507          * @param string $cookieValue The string in which to find the ID.
 508          * @return int|null The block ID, or null if the HMAC is present and invalid.
 509          */
 510         public function getIdFromCookieValue( $cookieValue ) {
 511                 // The cookie value must start with a number
 512                 if ( !is_numeric( substr( $cookieValue, 0, 1 ) ) ) {
 513                         return null;
 514                 }
 515
 516                 // Extract the ID prefix from the cookie value (may be the whole value, if no bang found).
 517                 $bangPos = strpos( $cookieValue, '!' );
 518                 $id = ( $bangPos === false ) ? $cookieValue : substr( $cookieValue, 0, $bangPos );
 519                 if ( !$this->options->get( 'SecretKey' ) ) {
 520                         // If there's no secret key, just use the ID as given.
 521                         return $id;
 522                 }
 523                 $storedHmac = substr( $cookieValue, $bangPos + 1 );
 524                 $calculatedHmac = MWCryptHash::hmac( $id, $this->options->get( 'SecretKey' ), false );
 525                 if ( $calculatedHmac === $storedHmac ) {
 526                         return $id;
 527                 } else {
 528                         return null;
 529                 }
 530         }
 531
 532         /**
 533          * Get the BlockID cookie's value for this block. This is usually the block ID concatenated
 534          * with an HMAC in order to avoid spoofing (T152951), but if wgSecretKey is not set will just
 535          * be the block ID.
 536          *
 537          * @since 1.34
 538          * @internal Should be private.
 539          *  Left public for backwards compatibility, until DatabaseBlock::getCookieValue is removed.
 540          * @param DatabaseBlock $block
 541          * @return string The block ID, probably concatenated with "!" and the HMAC.
 542          */
 543         public function getCookieValue( DatabaseBlock $block ) {
 544                 $id = $block->getId();
 545                 if ( !$this->options->get( 'SecretKey' ) ) {
 546                         // If there's no secret key, don't append a HMAC.
 547                         return $id;
 548                 }
 549                 $hmac = MWCryptHash::hmac( $id, $this->options->get( 'SecretKey' ), false );
 550                 $cookieValue = $id . '!' . $hmac;
 551                 return $cookieValue;
 552         }
 553
 554 }