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