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\User\UserIdentity;
  27 use MWCryptHash;
  28 use User;
  29 use WebRequest;
  30 use WebResponse;
  31 use Wikimedia\IPSet;
  32
  33 /**
  34  * A service class for checking blocks.
  35  * To obtain an instance, use MediaWikiServices::getInstance()->getBlockManager().
  36  *
  37  * @since 1.34 Refactored from User and Block.
  38  */
  39 class BlockManager {
  40         // TODO: This should be UserIdentity instead of User
  41         /** @var User */
  42         private $currentUser;
  43
  44         /** @var WebRequest */
  45         private $currentRequest;
  46
  47         /** @var bool */
  48         private $applyIpBlocksToXff;
  49
  50         /** @var bool */
  51         private $cookieSetOnAutoblock;
  52
  53         /** @var bool */
  54         private $cookieSetOnIpBlock;
  55
  56         /** @var array */
  57         private $dnsBlacklistUrls;
  58
  59         /** @var bool */
  60         private $enableDnsBlacklist;
  61
  62         /** @var array */
  63         private $proxyList;
  64
  65         /** @var array */
  66         private $proxyWhitelist;
  67
  68         /** @var string|bool */
  69         private $secretKey;
  70
  71         /** @var array */
  72         private $softBlockRanges;
  73
  74         /**
  75          * @param User $currentUser
  76          * @param WebRequest $currentRequest
  77          * @param bool $applyIpBlocksToXff
  78          * @param bool $cookieSetOnAutoblock
  79          * @param bool $cookieSetOnIpBlock
  80          * @param string[] $dnsBlacklistUrls
  81          * @param bool $enableDnsBlacklist
  82          * @param string[] $proxyList
  83          * @param string[] $proxyWhitelist
  84          * @param string $secretKey
  85          * @param array $softBlockRanges
  86          */
  87         public function __construct(
  88                 User $currentUser,
  89                 WebRequest $currentRequest,
  90                 $applyIpBlocksToXff,
  91                 $cookieSetOnAutoblock,
  92                 $cookieSetOnIpBlock,
  93                 array $dnsBlacklistUrls,
  94                 $enableDnsBlacklist,
  95                 array $proxyList,
  96                 array $proxyWhitelist,
  97                 $secretKey,
  98                 $softBlockRanges
  99         ) {
 100                 $this->currentUser = $currentUser;
 101                 $this->currentRequest = $currentRequest;
 102                 $this->applyIpBlocksToXff = $applyIpBlocksToXff;
 103                 $this->cookieSetOnAutoblock = $cookieSetOnAutoblock;
 104                 $this->cookieSetOnIpBlock = $cookieSetOnIpBlock;
 105                 $this->dnsBlacklistUrls = $dnsBlacklistUrls;
 106                 $this->enableDnsBlacklist = $enableDnsBlacklist;
 107                 $this->proxyList = $proxyList;
 108                 $this->proxyWhitelist = $proxyWhitelist;
 109                 $this->secretKey = $secretKey;
 110                 $this->softBlockRanges = $softBlockRanges;
 111         }
 112
 113         /**
 114          * Get the blocks that apply to a user. If there is only one, return that, otherwise
 115          * return a composite block that combines the strictest features of the applicable
 116          * blocks.
 117          *
 118          * TODO: $user should be UserIdentity instead of User
 119          *
 120          * @internal This should only be called by User::getBlockedStatus
 121          * @param User $user
 122          * @param bool $fromReplica Whether to check the replica DB first.
 123          *  To improve performance, non-critical checks are done against replica DBs.
 124          *  Check when actually saving should be done against master.
 125          * @return AbstractBlock|null The most relevant block, or null if there is no block.
 126          */
 127         public function getUserBlock( User $user, $fromReplica ) {
 128                 $isAnon = $user->getId() === 0;
 129
 130                 // TODO: If $user is the current user, we should use the current request. Otherwise,
 131                 // we should not look for XFF or cookie blocks.
 132                 $request = $user->getRequest();
 133
 134                 # We only need to worry about passing the IP address to the block generator if the
 135                 # user is not immune to autoblocks/hardblocks, and they are the current user so we
 136                 # know which IP address they're actually coming from
 137                 $ip = null;
 138                 $sessionUser = $this->currentUser;
 139                 // the session user is set up towards the end of Setup.php. Until then,
 140                 // assume it's a logged-out user.
 141                 $globalUserName = $sessionUser->isSafeToLoad()
 142                         ? $sessionUser->getName()
 143                         : IP::sanitizeIP( $this->currentRequest->getIP() );
 144                 if ( $user->getName() === $globalUserName && !$user->isAllowed( 'ipblock-exempt' ) ) {
 145                         $ip = $this->currentRequest->getIP();
 146                 }
 147
 148                 // User/IP blocking
 149                 // After this, $blocks is an array of blocks or an empty array
 150                 // TODO: remove dependency on DatabaseBlock
 151                 $blocks = DatabaseBlock::newListFromTarget( $user, $ip, !$fromReplica );
 152
 153                 // Cookie blocking
 154                 $cookieBlock = $this->getBlockFromCookieValue( $user, $request );
 155                 if ( $cookieBlock instanceof AbstractBlock ) {
 156                         $blocks[] = $cookieBlock;
 157                 }
 158
 159                 // Proxy blocking
 160                 if ( $ip !== null && !in_array( $ip, $this->proxyWhitelist ) ) {
 161                         // Local list
 162                         if ( $this->isLocallyBlockedProxy( $ip ) ) {
 163                                 $blocks[] = new SystemBlock( [
 164                                         'byText' => wfMessage( 'proxyblocker' )->text(),
 165                                         'reason' => wfMessage( 'proxyblockreason' )->plain(),
 166                                         'address' => $ip,
 167                                         'systemBlock' => 'proxy',
 168                                 ] );
 169                         } elseif ( $isAnon && $this->isDnsBlacklisted( $ip ) ) {
 170                                 $blocks[] = new SystemBlock( [
 171                                         'byText' => wfMessage( 'sorbs' )->text(),
 172                                         'reason' => wfMessage( 'sorbsreason' )->plain(),
 173                                         'address' => $ip,
 174                                         'systemBlock' => 'dnsbl',
 175                                 ] );
 176                         }
 177                 }
 178
 179                 // (T25343) Apply IP blocks to the contents of XFF headers, if enabled
 180                 if ( $this->applyIpBlocksToXff
 181                         && $ip !== null
 182                         && !in_array( $ip, $this->proxyWhitelist )
 183                 ) {
 184                         $xff = $request->getHeader( 'X-Forwarded-For' );
 185                         $xff = array_map( 'trim', explode( ',', $xff ) );
 186                         $xff = array_diff( $xff, [ $ip ] );
 187                         // TODO: remove dependency on DatabaseBlock
 188                         $xffblocks = DatabaseBlock::getBlocksForIPList( $xff, $isAnon, !$fromReplica );
 189                         $blocks = array_merge( $blocks, $xffblocks );
 190                 }
 191
 192                 // Soft blocking
 193                 if ( $ip !== null
 194                         && $isAnon
 195                         && IP::isInRanges( $ip, $this->softBlockRanges )
 196                 ) {
 197                         $blocks[] = new SystemBlock( [
 198                                 'address' => $ip,
 199                                 'byText' => 'MediaWiki default',
 200                                 'reason' => wfMessage( 'softblockrangesreason', $ip )->plain(),
 201                                 'anonOnly' => true,
 202                                 'systemBlock' => 'wgSoftBlockRanges',
 203                         ] );
 204                 }
 205
 206                 // Filter out any duplicated blocks, e.g. from the cookie
 207                 $blocks = $this->getUniqueBlocks( $blocks );
 208
 209                 if ( count( $blocks ) > 0 ) {
 210                         if ( count( $blocks ) === 1 ) {
 211                                 $block = $blocks[ 0 ];
 212                         } else {
 213                                 $block = new CompositeBlock( [
 214                                         'address' => $ip,
 215                                         'byText' => 'MediaWiki default',
 216                                         'reason' => wfMessage( 'blockedtext-composite-reason' )->plain(),
 217                                         'originalBlocks' => $blocks,
 218                                 ] );
 219                         }
 220                         return $block;
 221                 }
 222
 223                 return null;
 224         }
 225
 226         /**
 227          * Given a list of blocks, return a list of unique blocks.
 228          *
 229          * This usually means that each block has a unique ID. For a block with ID null,
 230          * if it's an autoblock, it will be filtered out if the parent block is present;
 231          * if not, it is assumed to be a unique system block, and kept.
 232          *
 233          * @param AbstractBlock[] $blocks
 234          * @return AbstractBlock[]
 235          */
 236         private function getUniqueBlocks( array $blocks ) {
 237                 $systemBlocks = [];
 238                 $databaseBlocks = [];
 239
 240                 foreach ( $blocks as $block ) {
 241                         if ( $block instanceof SystemBlock ) {
 242                                 $systemBlocks[] = $block;
 243                         } elseif ( $block->getType() === DatabaseBlock::TYPE_AUTO ) {
 244                                 if ( !isset( $databaseBlocks[$block->getParentBlockId()] ) ) {
 245                                         $databaseBlocks[$block->getParentBlockId()] = $block;
 246                                 }
 247                         } else {
 248                                 $databaseBlocks[$block->getId()] = $block;
 249                         }
 250                 }
 251
 252                 return array_merge( $systemBlocks, $databaseBlocks );
 253         }
 254
 255         /**
 256          * Try to load a block from an ID given in a cookie value. If the block is invalid
 257          * or doesn't exist, remove the cookie.
 258          *
 259          * @param UserIdentity $user
 260          * @param WebRequest $request
 261          * @return DatabaseBlock|bool The block object, or false if none could be loaded.
 262          */
 263         private function getBlockFromCookieValue(
 264                 UserIdentity $user,
 265                 WebRequest $request
 266         ) {
 267                 $blockCookieId = $this->getIdFromCookieValue( $request->getCookie( 'BlockID' ) );
 268
 269                 if ( $blockCookieId !== null ) {
 270                         // TODO: remove dependency on DatabaseBlock
 271                         $block = DatabaseBlock::newFromID( $blockCookieId );
 272                         if (
 273                                 $block instanceof DatabaseBlock &&
 274                                 $this->shouldApplyCookieBlock( $block, $user->isAnon() )
 275                         ) {
 276                                 return $block;
 277                         }
 278                         $this->clearBlockCookie( $request->response() );
 279                 }
 280
 281                 return false;
 282         }
 283
 284         /**
 285          * Check if the block loaded from the cookie should be applied.
 286          *
 287          * @param DatabaseBlock $block
 288          * @param bool $isAnon The user is logged out
 289          * @return bool The block sould be applied
 290          */
 291         private function shouldApplyCookieBlock( DatabaseBlock $block, $isAnon ) {
 292                 if ( !$block->isExpired() ) {
 293                         switch ( $block->getType() ) {
 294                                 case DatabaseBlock::TYPE_IP:
 295                                 case DatabaseBlock::TYPE_RANGE:
 296                                         // If block is type IP or IP range, load only
 297                                         // if user is not logged in (T152462)
 298                                         return $isAnon && $this->cookieSetOnIpBlock;
 299                                 case DatabaseBlock::TYPE_USER:
 300                                         return $this->cookieSetOnAutoblock && $block->isAutoblocking();
 301                                 default:
 302                                         return false;
 303                         }
 304                 }
 305                 return false;
 306         }
 307
 308         /**
 309          * Check if an IP address is in the local proxy list
 310          *
 311          * @param string $ip
 312          * @return bool
 313          */
 314         private function isLocallyBlockedProxy( $ip ) {
 315                 if ( !$this->proxyList ) {
 316                         return false;
 317                 }
 318
 319                 if ( !is_array( $this->proxyList ) ) {
 320                         // Load values from the specified file
 321                         $this->proxyList = array_map( 'trim', file( $this->proxyList ) );
 322                 }
 323
 324                 $resultProxyList = [];
 325                 $deprecatedIPEntries = [];
 326
 327                 // backward compatibility: move all ip addresses in keys to values
 328                 foreach ( $this->proxyList as $key => $value ) {
 329                         $keyIsIP = IP::isIPAddress( $key );
 330                         $valueIsIP = IP::isIPAddress( $value );
 331                         if ( $keyIsIP && !$valueIsIP ) {
 332                                 $deprecatedIPEntries[] = $key;
 333                                 $resultProxyList[] = $key;
 334                         } elseif ( $keyIsIP && $valueIsIP ) {
 335                                 $deprecatedIPEntries[] = $key;
 336                                 $resultProxyList[] = $key;
 337                                 $resultProxyList[] = $value;
 338                         } else {
 339                                 $resultProxyList[] = $value;
 340                         }
 341                 }
 342
 343                 if ( $deprecatedIPEntries ) {
 344                         wfDeprecated(
 345                                 'IP addresses in the keys of $wgProxyList (found the following IP addresses in keys: ' .
 346                                 implode( ', ', $deprecatedIPEntries ) . ', please move them to values)', '1.30' );
 347                 }
 348
 349                 $proxyListIPSet = new IPSet( $resultProxyList );
 350                 return $proxyListIPSet->match( $ip );
 351         }
 352
 353         /**
 354          * Whether the given IP is in a DNS blacklist.
 355          *
 356          * @param string $ip IP to check
 357          * @param bool $checkWhitelist Whether to check the whitelist first
 358          * @return bool True if blacklisted.
 359          */
 360         public function isDnsBlacklisted( $ip, $checkWhitelist = false ) {
 361                 if ( !$this->enableDnsBlacklist ||
 362                         ( $checkWhitelist && in_array( $ip, $this->proxyWhitelist ) )
 363                 ) {
 364                         return false;
 365                 }
 366
 367                 return $this->inDnsBlacklist( $ip, $this->dnsBlacklistUrls );
 368         }
 369
 370         /**
 371          * Whether the given IP is in a given DNS blacklist.
 372          *
 373          * @param string $ip IP to check
 374          * @param array $bases Array of Strings: URL of the DNS blacklist
 375          * @return bool True if blacklisted.
 376          */
 377         private function inDnsBlacklist( $ip, array $bases ) {
 378                 $found = false;
 379                 // @todo FIXME: IPv6 ???  (https://bugs.php.net/bug.php?id=33170)
 380                 if ( IP::isIPv4( $ip ) ) {
 381                         // Reverse IP, T23255
 382                         $ipReversed = implode( '.', array_reverse( explode( '.', $ip ) ) );
 383
 384                         foreach ( $bases as $base ) {
 385                                 // Make hostname
 386                                 // If we have an access key, use that too (ProjectHoneypot, etc.)
 387                                 $basename = $base;
 388                                 if ( is_array( $base ) ) {
 389                                         if ( count( $base ) >= 2 ) {
 390                                                 // Access key is 1, base URL is 0
 391                                                 $hostname = "{$base[1]}.$ipReversed.{$base[0]}";
 392                                         } else {
 393                                                 $hostname = "$ipReversed.{$base[0]}";
 394                                         }
 395                                         $basename = $base[0];
 396                                 } else {
 397                                         $hostname = "$ipReversed.$base";
 398                                 }
 399
 400                                 // Send query
 401                                 $ipList = $this->checkHost( $hostname );
 402
 403                                 if ( $ipList ) {
 404                                         wfDebugLog(
 405                                                 'dnsblacklist',
 406                                                 "Hostname $hostname is {$ipList[0]}, it's a proxy says $basename!"
 407                                         );
 408                                         $found = true;
 409                                         break;
 410                                 }
 411
 412                                 wfDebugLog( 'dnsblacklist', "Requested $hostname, not found in $basename." );
 413                         }
 414                 }
 415
 416                 return $found;
 417         }
 418
 419         /**
 420          * Wrapper for mocking in tests.
 421          *
 422          * @param string $hostname DNSBL query
 423          * @return string[]|bool IPv4 array, or false if the IP is not blacklisted
 424          */
 425         protected function checkHost( $hostname ) {
 426                 return gethostbynamel( $hostname );
 427         }
 428
 429         /**
 430          * Set the 'BlockID' cookie depending on block type and user authentication status.
 431          *
 432          * @since 1.34
 433          * @param User $user
 434          */
 435         public function trackBlockWithCookie( User $user ) {
 436                 $request = $user->getRequest();
 437                 if ( $request->getCookie( 'BlockID' ) !== null ) {
 438                         // User already has a block cookie
 439                         return;
 440                 }
 441
 442                 // Defer checks until the user has been fully loaded to avoid circular dependency
 443                 // of User on itself (T180050 and T226777)
 444                 DeferredUpdates::addCallableUpdate(
 445                         function () use ( $user, $request ) {
 446                                 $block = $user->getBlock();
 447                                 $response = $request->response();
 448                                 $isAnon = $user->isAnon();
 449
 450                                 if ( $block ) {
 451                                         if ( $block instanceof CompositeBlock ) {
 452                                                 // TODO: Improve on simply tracking the first trackable block (T225654)
 453                                                 foreach ( $block->getOriginalBlocks() as $originalBlock ) {
 454                                                         if ( $this->shouldTrackBlockWithCookie( $originalBlock, $isAnon ) ) {
 455                                                                 $this->setBlockCookie( $originalBlock, $response );
 456                                                                 return;
 457                                                         }
 458                                                 }
 459                                         } else {
 460                                                 if ( $this->shouldTrackBlockWithCookie( $block, $isAnon ) ) {
 461                                                         $this->setBlockCookie( $block, $response );
 462                                                 }
 463                                         }
 464                                 }
 465                         },
 466                         DeferredUpdates::PRESEND
 467                 );
 468         }
 469
 470         /**
 471          * Set the 'BlockID' cookie to this block's ID and expiry time. The cookie's expiry will be
 472          * the same as the block's, to a maximum of 24 hours.
 473          *
 474          * @since 1.34
 475          * @internal Should be private.
 476          *  Left public for backwards compatibility, until DatabaseBlock::setCookie is removed.
 477          * @param DatabaseBlock $block
 478          * @param WebResponse $response The response on which to set the cookie.
 479          */
 480         public function setBlockCookie( DatabaseBlock $block, WebResponse $response ) {
 481                 // Calculate the default expiry time.
 482                 $maxExpiryTime = wfTimestamp( TS_MW, wfTimestamp() + ( 24 * 60 * 60 ) );
 483
 484                 // Use the block's expiry time only if it's less than the default.
 485                 $expiryTime = $block->getExpiry();
 486                 if ( $expiryTime === 'infinity' || $expiryTime > $maxExpiryTime ) {
 487                         $expiryTime = $maxExpiryTime;
 488                 }
 489
 490                 // Set the cookie. Reformat the MediaWiki datetime as a Unix timestamp for the cookie.
 491                 $expiryValue = DateTime::createFromFormat( 'YmdHis', $expiryTime )->format( 'U' );
 492                 $cookieOptions = [ 'httpOnly' => false ];
 493                 $cookieValue = $this->getCookieValue( $block );
 494                 $response->setCookie( 'BlockID', $cookieValue, $expiryValue, $cookieOptions );
 495         }
 496
 497         /**
 498          * Check if the block should be tracked with a cookie.
 499          *
 500          * @param AbstractBlock $block
 501          * @param bool $isAnon The user is logged out
 502          * @return bool The block sould be tracked with a cookie
 503          */
 504         private function shouldTrackBlockWithCookie( AbstractBlock $block, $isAnon ) {
 505                 if ( $block instanceof DatabaseBlock ) {
 506                         switch ( $block->getType() ) {
 507                                 case DatabaseBlock::TYPE_IP:
 508                                 case DatabaseBlock::TYPE_RANGE:
 509                                         return $isAnon && $this->cookieSetOnIpBlock;
 510                                 case DatabaseBlock::TYPE_USER:
 511                                         return !$isAnon && $this->cookieSetOnAutoblock && $block->isAutoblocking();
 512                                 default:
 513                                         return false;
 514                         }
 515                 }
 516                 return false;
 517         }
 518
 519         /**
 520          * Unset the 'BlockID' cookie.
 521          *
 522          * @since 1.34
 523          * @param WebResponse $response
 524          */
 525         public static function clearBlockCookie( WebResponse $response ) {
 526                 $response->clearCookie( 'BlockID', [ 'httpOnly' => false ] );
 527         }
 528
 529         /**
 530          * Get the stored ID from the 'BlockID' cookie. The cookie's value is usually a combination of
 531          * the ID and a HMAC (see DatabaseBlock::setCookie), but will sometimes only be the ID.
 532          *
 533          * @since 1.34
 534          * @internal Should be private.
 535          *  Left public for backwards compatibility, until DatabaseBlock::getIdFromCookieValue is removed.
 536          * @param string $cookieValue The string in which to find the ID.
 537          * @return int|null The block ID, or null if the HMAC is present and invalid.
 538          */
 539         public function getIdFromCookieValue( $cookieValue ) {
 540                 // The cookie value must start with a number
 541                 if ( !is_numeric( substr( $cookieValue, 0, 1 ) ) ) {
 542                         return null;
 543                 }
 544
 545                 // Extract the ID prefix from the cookie value (may be the whole value, if no bang found).
 546                 $bangPos = strpos( $cookieValue, '!' );
 547                 $id = ( $bangPos === false ) ? $cookieValue : substr( $cookieValue, 0, $bangPos );
 548                 if ( !$this->secretKey ) {
 549                         // If there's no secret key, just use the ID as given.
 550                         return $id;
 551                 }
 552                 $storedHmac = substr( $cookieValue, $bangPos + 1 );
 553                 $calculatedHmac = MWCryptHash::hmac( $id, $this->secretKey, false );
 554                 if ( $calculatedHmac === $storedHmac ) {
 555                         return $id;
 556                 } else {
 557                         return null;
 558                 }
 559         }
 560
 561         /**
 562          * Get the BlockID cookie's value for this block. This is usually the block ID concatenated
 563          * with an HMAC in order to avoid spoofing (T152951), but if wgSecretKey is not set will just
 564          * be the block ID.
 565          *
 566          * @since 1.34
 567          * @internal Should be private.
 568          *  Left public for backwards compatibility, until DatabaseBlock::getCookieValue is removed.
 569          * @param DatabaseBlock $block
 570          * @return string The block ID, probably concatenated with "!" and the HMAC.
 571          */
 572         public function getCookieValue( DatabaseBlock $block ) {
 573                 $id = $block->getId();
 574                 if ( !$this->secretKey ) {
 575                         // If there's no secret key, don't append a HMAC.
 576                         return $id;
 577                 }
 578                 $hmac = MWCryptHash::hmac( $id, $this->secretKey, false );
 579                 $cookieValue = $id . '!' . $hmac;
 580                 return $cookieValue;
 581         }
 582
 583 }