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