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