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