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