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 Psr\Log\LoggerInterface;
  33 use User;
  34 use WebRequest;
  35 use WebResponse;
  36 use Wikimedia\IPSet;
  37
  38 /**
  39  * A service class for checking blocks.
  40  * To obtain an instance, use MediaWikiServices::getInstance()->getBlockManager().
  41  *
  42  * @since 1.34 Refactored from User and Block.
  43  */
  44 class BlockManager {
  45         /** @var PermissionManager */
  46         private $permissionManager;
  47
  48         /** @var ServiceOptions */
  49         private $options;
  50
  51         /**
  52          * TODO Make this a const when HHVM support is dropped (T192166)
  53          *
  54          * @var array
  55          * @since 1.34
  56          */
  57         public static $constructorOptions = [
  58                 'ApplyIpBlocksToXff',
  59                 'CookieSetOnAutoblock',
  60                 'CookieSetOnIpBlock',
  61                 'DnsBlacklistUrls',
  62                 'EnableDnsBlacklist',
  63                 'ProxyList',
  64                 'ProxyWhitelist',
  65                 'SecretKey',
  66                 'SoftBlockRanges',
  67         ];
  68
  69         /** @var LoggerInterface */
  70         private $logger;
  71
  72         /**
  73          * @param ServiceOptions $options
  74          * @param PermissionManager $permissionManager
  75          * @param LoggerInterface $logger
  76          */
  77         public function __construct(
  78                 ServiceOptions $options,
  79                 PermissionManager $permissionManager,
  80                 LoggerInterface $logger
  81         ) {
  82                 $options->assertRequiredOptions( self::$constructorOptions );
  83                 $this->options = $options;
  84                 $this->permissionManager = $permissionManager;
  85                 $this->logger = $logger;
  86         }
  87
  88         /**
  89          * Get the blocks that apply to a user. If there is only one, return that, otherwise
  90          * return a composite block that combines the strictest features of the applicable
  91          * blocks.
  92          *
  93          * Different blocks may be sought, depending on the user and their permissions. The
  94          * user may be:
  95          * (1) The global user (and can be affected by IP blocks). The global request object
  96          * is needed for checking the IP address, the XFF header and the cookies.
  97          * (2) The global user (and exempt from IP blocks). The global request object is
  98          * needed for checking the cookies.
  99          * (3) Another user (not the global user). No request object is available or needed;
 100          * just look for a block against the user account.
 101          *
 102          * Cases #1 and #2 check whether the global user is blocked in practice; the block
 103          * may due to their user account being blocked or to an IP address block or cookie
 104          * block (or multiple of these). Case #3 simply checks whether a user's account is
 105          * blocked, and does not determine whether the person using that account is affected
 106          * in practice by any IP address or cookie blocks.
 107          *
 108          * @internal This should only be called by User::getBlockedStatus
 109          * @param User $user
 110          * @param WebRequest|null $request The global request object if the user is the
 111          *  global user (cases #1 and #2), otherwise null (case #3). The IP address and
 112          *  information from the request header are needed to find some types of blocks.
 113          * @param bool $fromReplica Whether to check the replica DB first.
 114          *  To improve performance, non-critical checks are done against replica DBs.
 115          *  Check when actually saving should be done against master.
 116          * @return AbstractBlock|null The most relevant block, or null if there is no block.
 117          */
 118         public function getUserBlock( User $user, $request, $fromReplica ) {
 119                 $fromMaster = !$fromReplica;
 120                 $ip = null;
 121
 122                 // If this is the global user, they may be affected by IP blocks (case #1),
 123                 // or they may be exempt (case #2). If affected, look for additional blocks
 124                 // against the IP address.
 125                 $checkIpBlocks = $request &&
 126                         !$this->permissionManager->userHasRight( $user, 'ipblock-exempt' );
 127
 128                 if ( $request && $checkIpBlocks ) {
 129
 130                         // Case #1: checking the global user, including IP blocks
 131                         $ip = $request->getIP();
 132                         // TODO: remove dependency on DatabaseBlock (T221075)
 133                         $blocks = DatabaseBlock::newListFromTarget( $user, $ip, $fromMaster );
 134                         $this->getAdditionalIpBlocks( $blocks, $request, !$user->isRegistered(), $fromMaster );
 135                         $this->getCookieBlock( $blocks, $user, $request );
 136
 137                 } elseif ( $request ) {
 138
 139                         // Case #2: checking the global user, but they are exempt from IP blocks
 140                         // TODO: remove dependency on DatabaseBlock (T221075)
 141                         $blocks = DatabaseBlock::newListFromTarget( $user, null, $fromMaster );
 142                         $this->getCookieBlock( $blocks, $user, $request );
 143
 144                 } else {
 145
 146                         // Case #3: checking whether a user's account is blocked
 147                         // TODO: remove dependency on DatabaseBlock (T221075)
 148                         $blocks = DatabaseBlock::newListFromTarget( $user, null, $fromMaster );
 149
 150                 }
 151
 152                 // Filter out any duplicated blocks, e.g. from the cookie
 153                 $blocks = $this->getUniqueBlocks( $blocks );
 154
 155                 $block = null;
 156                 if ( count( $blocks ) > 0 ) {
 157                         if ( count( $blocks ) === 1 ) {
 158                                 $block = $blocks[ 0 ];
 159                         } else {
 160                                 $block = new CompositeBlock( [
 161                                         'address' => $ip,
 162                                         'byText' => 'MediaWiki default',
 163                                         'reason' => wfMessage( 'blockedtext-composite-reason' )->plain(),
 164                                         'originalBlocks' => $blocks,
 165                                 ] );
 166                         }
 167                 }
 168
 169                 Hooks::run( 'GetUserBlock', [ clone $user, $ip, &$block ] );
 170
 171                 return $block;
 172         }
 173
 174         /**
 175          * Get the cookie block, if there is one.
 176          *
 177          * @param AbstractBlock[] &$blocks
 178          * @param UserIdentity $user
 179          * @param WebRequest $request
 180          * @return void
 181          */
 182         private function getCookieBlock( &$blocks, UserIdentity $user, WebRequest $request ) {
 183                 $cookieBlock = $this->getBlockFromCookieValue( $user, $request );
 184                 if ( $cookieBlock instanceof DatabaseBlock ) {
 185                         $blocks[] = $cookieBlock;
 186                 }
 187         }
 188
 189         /**
 190          * Check for any additional blocks against the IP address or any IPs in the XFF header.
 191          *
 192          * @param AbstractBlock[] &$blocks Blocks found so far
 193          * @param WebRequest $request
 194          * @param bool $isAnon The user is logged out
 195          * @param bool $fromMaster
 196          * @return void
 197          */
 198         private function getAdditionalIpBlocks( &$blocks, WebRequest $request, $isAnon, $fromMaster ) {
 199                 $ip = $request->getIP();
 200
 201                 // Proxy blocking
 202                 if ( !in_array( $ip, $this->options->get( 'ProxyWhitelist' ) ) ) {
 203                         // Local list
 204                         if ( $this->isLocallyBlockedProxy( $ip ) ) {
 205                                 $blocks[] = new SystemBlock( [
 206                                         'byText' => wfMessage( 'proxyblocker' )->text(),
 207                                         'reason' => wfMessage( 'proxyblockreason' )->plain(),
 208                                         'address' => $ip,
 209                                         'systemBlock' => 'proxy',
 210                                 ] );
 211                         } elseif ( $isAnon && $this->isDnsBlacklisted( $ip ) ) {
 212                                 $blocks[] = new SystemBlock( [
 213                                         'byText' => wfMessage( 'sorbs' )->text(),
 214                                         'reason' => wfMessage( 'sorbsreason' )->plain(),
 215                                         'address' => $ip,
 216                                         'systemBlock' => 'dnsbl',
 217                                 ] );
 218                         }
 219                 }
 220
 221                 // Soft blocking
 222                 if ( $isAnon && IP::isInRanges( $ip, $this->options->get( 'SoftBlockRanges' ) ) ) {
 223                         $blocks[] = new SystemBlock( [
 224                                 'address' => $ip,
 225                                 'byText' => 'MediaWiki default',
 226                                 'reason' => wfMessage( 'softblockrangesreason', $ip )->plain(),
 227                                 'anonOnly' => true,
 228                                 'systemBlock' => 'wgSoftBlockRanges',
 229                         ] );
 230                 }
 231
 232                 // (T25343) Apply IP blocks to the contents of XFF headers, if enabled
 233                 if ( $this->options->get( 'ApplyIpBlocksToXff' )
 234                         && !in_array( $ip, $this->options->get( 'ProxyWhitelist' ) )
 235                 ) {
 236                         $xff = $request->getHeader( 'X-Forwarded-For' );
 237                         $xff = array_map( 'trim', explode( ',', $xff ) );
 238                         $xff = array_diff( $xff, [ $ip ] );
 239                         // TODO: remove dependency on DatabaseBlock (T221075)
 240                         $xffblocks = DatabaseBlock::getBlocksForIPList( $xff, $isAnon, $fromMaster );
 241                         $blocks = array_merge( $blocks, $xffblocks );
 242                 }
 243         }
 244
 245         /**
 246          * Given a list of blocks, return a list of unique blocks.
 247          *
 248          * This usually means that each block has a unique ID. For a block with ID null,
 249          * if it's an autoblock, it will be filtered out if the parent block is present;
 250          * if not, it is assumed to be a unique system block, and kept.
 251          *
 252          * @param AbstractBlock[] $blocks
 253          * @return AbstractBlock[]
 254          */
 255         private function getUniqueBlocks( array $blocks ) {
 256                 $systemBlocks = [];
 257                 $databaseBlocks = [];
 258
 259                 foreach ( $blocks as $block ) {
 260                         if ( $block instanceof SystemBlock ) {
 261                                 $systemBlocks[] = $block;
 262                         } elseif ( $block->getType() === DatabaseBlock::TYPE_AUTO ) {
 263                                 /** @var DatabaseBlock $block */
 264                                 '@phan-var DatabaseBlock $block';
 265                                 if ( !isset( $databaseBlocks[$block->getParentBlockId()] ) ) {
 266                                         $databaseBlocks[$block->getParentBlockId()] = $block;
 267                                 }
 268                         } else {
 269                                 $databaseBlocks[$block->getId()] = $block;
 270                         }
 271                 }
 272
 273                 return array_values( array_merge( $systemBlocks, $databaseBlocks ) );
 274         }
 275
 276         /**
 277          * Try to load a block from an ID given in a cookie value. If the block is invalid
 278          * doesn't exist, or the cookie value is malformed, remove the cookie.
 279          *
 280          * @param UserIdentity $user
 281          * @param WebRequest $request
 282          * @return DatabaseBlock|bool The block object, or false if none could be loaded.
 283          */
 284         private function getBlockFromCookieValue(
 285                 UserIdentity $user,
 286                 WebRequest $request
 287         ) {
 288                 $cookieValue = $request->getCookie( 'BlockID' );
 289                 if ( is_null( $cookieValue ) ) {
 290                         return false;
 291                 }
 292
 293                 $blockCookieId = $this->getIdFromCookieValue( $cookieValue );
 294                 if ( !is_null( $blockCookieId ) ) {
 295                         // TODO: remove dependency on DatabaseBlock (T221075)
 296                         $block = DatabaseBlock::newFromID( $blockCookieId );
 297                         if (
 298                                 $block instanceof DatabaseBlock &&
 299                                 $this->shouldApplyCookieBlock( $block, !$user->isRegistered() )
 300                         ) {
 301                                 return $block;
 302                         }
 303                 }
 304
 305                 $this->clearBlockCookie( $request->response() );
 306
 307                 return false;
 308         }
 309
 310         /**
 311          * Check if the block loaded from the cookie should be applied.
 312          *
 313          * @param DatabaseBlock $block
 314          * @param bool $isAnon The user is logged out
 315          * @return bool The block sould be applied
 316          */
 317         private function shouldApplyCookieBlock( DatabaseBlock $block, $isAnon ) {
 318                 if ( !$block->isExpired() ) {
 319                         switch ( $block->getType() ) {
 320                                 case DatabaseBlock::TYPE_IP:
 321                                 case DatabaseBlock::TYPE_RANGE:
 322                                         // If block is type IP or IP range, load only
 323                                         // if user is not logged in (T152462)
 324                                         return $isAnon &&
 325                                                 $this->options->get( 'CookieSetOnIpBlock' );
 326                                 case DatabaseBlock::TYPE_USER:
 327                                         return $block->isAutoblocking() &&
 328                                                 $this->options->get( 'CookieSetOnAutoblock' );
 329                                 default:
 330                                         return false;
 331                         }
 332                 }
 333                 return false;
 334         }
 335
 336         /**
 337          * Check if an IP address is in the local proxy list
 338          *
 339          * @param string $ip
 340          * @return bool
 341          */
 342         private function isLocallyBlockedProxy( $ip ) {
 343                 $proxyList = $this->options->get( 'ProxyList' );
 344                 if ( !$proxyList ) {
 345                         return false;
 346                 }
 347
 348                 if ( !is_array( $proxyList ) ) {
 349                         // Load values from the specified file
 350                         $proxyList = array_map( 'trim', file( $proxyList ) );
 351                 }
 352
 353                 $proxyListIPSet = new IPSet( $proxyList );
 354                 return $proxyListIPSet->match( $ip );
 355         }
 356
 357         /**
 358          * Whether the given IP is in a DNS blacklist.
 359          *
 360          * @param string $ip IP to check
 361          * @param bool $checkWhitelist Whether to check the whitelist first
 362          * @return bool True if blacklisted.
 363          */
 364         public function isDnsBlacklisted( $ip, $checkWhitelist = false ) {
 365                 if ( !$this->options->get( 'EnableDnsBlacklist' ) ||
 366                         ( $checkWhitelist && in_array( $ip, $this->options->get( 'ProxyWhitelist' ) ) )
 367                 ) {
 368                         return false;
 369                 }
 370
 371                 return $this->inDnsBlacklist( $ip, $this->options->get( 'DnsBlacklistUrls' ) );
 372         }
 373
 374         /**
 375          * Whether the given IP is in a given DNS blacklist.
 376          *
 377          * @param string $ip IP to check
 378          * @param array $bases Array of Strings: URL of the DNS blacklist
 379          * @return bool True if blacklisted.
 380          */
 381         private function inDnsBlacklist( $ip, array $bases ) {
 382                 $found = false;
 383                 // @todo FIXME: IPv6 ???  (https://bugs.php.net/bug.php?id=33170)
 384                 if ( IP::isIPv4( $ip ) ) {
 385                         // Reverse IP, T23255
 386                         $ipReversed = implode( '.', array_reverse( explode( '.', $ip ) ) );
 387
 388                         foreach ( $bases as $base ) {
 389                                 // Make hostname
 390                                 // If we have an access key, use that too (ProjectHoneypot, etc.)
 391                                 $basename = $base;
 392                                 if ( is_array( $base ) ) {
 393                                         if ( count( $base ) >= 2 ) {
 394                                                 // Access key is 1, base URL is 0
 395                                                 $hostname = "{$base[1]}.$ipReversed.{$base[0]}";
 396                                         } else {
 397                                                 $hostname = "$ipReversed.{$base[0]}";
 398                                         }
 399                                         $basename = $base[0];
 400                                 } else {
 401                                         $hostname = "$ipReversed.$base";
 402                                 }
 403
 404                                 // Send query
 405                                 $ipList = $this->checkHost( $hostname );
 406
 407                                 if ( $ipList ) {
 408                                         $this->logger->info(
 409                                                 "Hostname $hostname is {$ipList[0]}, it's a proxy says $basename!"
 410                                         );
 411                                         $found = true;
 412                                         break;
 413                                 }
 414
 415                                 $this->logger->debug( "Requested $hostname, not found in $basename." );
 416                         }
 417                 }
 418
 419                 return $found;
 420         }
 421
 422         /**
 423          * Wrapper for mocking in tests.
 424          *
 425          * @param string $hostname DNSBL query
 426          * @return string[]|bool IPv4 array, or false if the IP is not blacklisted
 427          */
 428         protected function checkHost( $hostname ) {
 429                 return gethostbynamel( $hostname );
 430         }
 431
 432         /**
 433          * Set the 'BlockID' cookie depending on block type and user authentication status.
 434          *
 435          * @since 1.34
 436          * @param User $user
 437          */
 438         public function trackBlockWithCookie( User $user ) {
 439                 $request = $user->getRequest();
 440                 if ( $request->getCookie( 'BlockID' ) !== null ) {
 441                         // User already has a block cookie
 442                         return;
 443                 }
 444
 445                 // Defer checks until the user has been fully loaded to avoid circular dependency
 446                 // of User on itself (T180050 and T226777)
 447                 DeferredUpdates::addCallableUpdate(
 448                         function () use ( $user, $request ) {
 449                                 $block = $user->getBlock();
 450                                 $response = $request->response();
 451                                 $isAnon = $user->isAnon();
 452
 453                                 if ( $block ) {
 454                                         if ( $block instanceof CompositeBlock ) {
 455                                                 // TODO: Improve on simply tracking the first trackable block (T225654)
 456                                                 foreach ( $block->getOriginalBlocks() as $originalBlock ) {
 457                                                         if ( $this->shouldTrackBlockWithCookie( $originalBlock, $isAnon ) ) {
 458                                                                 '@phan-var DatabaseBlock $originalBlock';
 459                                                                 $this->setBlockCookie( $originalBlock, $response );
 460                                                                 return;
 461                                                         }
 462                                                 }
 463                                         } else {
 464                                                 if ( $this->shouldTrackBlockWithCookie( $block, $isAnon ) ) {
 465                                                         '@phan-var DatabaseBlock $block';
 466                                                         $this->setBlockCookie( $block, $response );
 467                                                 }
 468                                         }
 469                                 }
 470                         },
 471                         DeferredUpdates::PRESEND
 472                 );
 473         }
 474
 475         /**
 476          * Set the 'BlockID' cookie to this block's ID and expiry time. The cookie's expiry will be
 477          * the same as the block's, to a maximum of 24 hours.
 478          *
 479          * @since 1.34
 480          * @internal Should be private.
 481          *  Left public for backwards compatibility, until DatabaseBlock::setCookie is removed.
 482          * @param DatabaseBlock $block
 483          * @param WebResponse $response The response on which to set the cookie.
 484          */
 485         public function setBlockCookie( DatabaseBlock $block, WebResponse $response ) {
 486                 // Calculate the default expiry time.
 487                 $maxExpiryTime = wfTimestamp( TS_MW, wfTimestamp() + ( 24 * 60 * 60 ) );
 488
 489                 // Use the block's expiry time only if it's less than the default.
 490                 $expiryTime = $block->getExpiry();
 491                 if ( $expiryTime === 'infinity' || $expiryTime > $maxExpiryTime ) {
 492                         $expiryTime = $maxExpiryTime;
 493                 }
 494
 495                 // Set the cookie. Reformat the MediaWiki datetime as a Unix timestamp for the cookie.
 496                 $expiryValue = DateTime::createFromFormat(
 497                         'YmdHis',
 498                         $expiryTime,
 499                         new DateTimeZone( 'UTC' )
 500                 )->format( 'U' );
 501                 $cookieOptions = [ 'httpOnly' => false ];
 502                 $cookieValue = $this->getCookieValue( $block );
 503                 $response->setCookie( 'BlockID', $cookieValue, $expiryValue, $cookieOptions );
 504         }
 505
 506         /**
 507          * Check if the block should be tracked with a cookie.
 508          *
 509          * @param AbstractBlock $block
 510          * @param bool $isAnon The user is logged out
 511          * @return bool The block sould be tracked with a cookie
 512          */
 513         private function shouldTrackBlockWithCookie( AbstractBlock $block, $isAnon ) {
 514                 if ( $block instanceof DatabaseBlock ) {
 515                         switch ( $block->getType() ) {
 516                                 case DatabaseBlock::TYPE_IP:
 517                                 case DatabaseBlock::TYPE_RANGE:
 518                                         return $isAnon && $this->options->get( 'CookieSetOnIpBlock' );
 519                                 case DatabaseBlock::TYPE_USER:
 520                                         return !$isAnon &&
 521                                                 $this->options->get( 'CookieSetOnAutoblock' ) &&
 522                                                 $block->isAutoblocking();
 523                                 default:
 524                                         return false;
 525                         }
 526                 }
 527                 return false;
 528         }
 529
 530         /**
 531          * Unset the 'BlockID' cookie.
 532          *
 533          * @since 1.34
 534          * @param WebResponse $response
 535          */
 536         public static function clearBlockCookie( WebResponse $response ) {
 537                 $response->clearCookie( 'BlockID', [ 'httpOnly' => false ] );
 538         }
 539
 540         /**
 541          * Get the stored ID from the 'BlockID' cookie. The cookie's value is usually a combination of
 542          * the ID and a HMAC (see DatabaseBlock::setCookie), but will sometimes only be the ID.
 543          *
 544          * @since 1.34
 545          * @internal Should be private.
 546          *  Left public for backwards compatibility, until DatabaseBlock::getIdFromCookieValue is removed.
 547          * @param string $cookieValue The string in which to find the ID.
 548          * @return int|null The block ID, or null if the HMAC is present and invalid.
 549          */
 550         public function getIdFromCookieValue( $cookieValue ) {
 551                 // The cookie value must start with a number
 552                 if ( !is_numeric( substr( $cookieValue, 0, 1 ) ) ) {
 553                         return null;
 554                 }
 555
 556                 // Extract the ID prefix from the cookie value (may be the whole value, if no bang found).
 557                 $bangPos = strpos( $cookieValue, '!' );
 558                 $id = ( $bangPos === false ) ? $cookieValue : substr( $cookieValue, 0, $bangPos );
 559                 if ( !$this->options->get( 'SecretKey' ) ) {
 560                         // If there's no secret key, just use the ID as given.
 561                         return $id;
 562                 }
 563                 $storedHmac = substr( $cookieValue, $bangPos + 1 );
 564                 $calculatedHmac = MWCryptHash::hmac( $id, $this->options->get( 'SecretKey' ), false );
 565                 if ( $calculatedHmac === $storedHmac ) {
 566                         return $id;
 567                 } else {
 568                         return null;
 569                 }
 570         }
 571
 572         /**
 573          * Get the BlockID cookie's value for this block. This is usually the block ID concatenated
 574          * with an HMAC in order to avoid spoofing (T152951), but if wgSecretKey is not set will just
 575          * be the block ID.
 576          *
 577          * @since 1.34
 578          * @internal Should be private.
 579          *  Left public for backwards compatibility, until DatabaseBlock::getCookieValue is removed.
 580          * @param DatabaseBlock $block
 581          * @return string The block ID, probably concatenated with "!" and the HMAC.
 582          */
 583         public function getCookieValue( DatabaseBlock $block ) {
 584                 $id = $block->getId();
 585                 if ( !$this->options->get( 'SecretKey' ) ) {
 586                         // If there's no secret key, don't append a HMAC.
 587                         return $id;
 588                 }
 589                 $hmac = MWCryptHash::hmac( $id, $this->options->get( 'SecretKey' ), false );
 590                 $cookieValue = $id . '!' . $hmac;
 591                 return $cookieValue;
 592         }
 593
 594 }