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