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 and return the most relevant one.
 114          *
 115          * TODO: $user should be UserIdentity instead of User
 116          *
 117          * @internal This should only be called by User::getBlockedStatus
 118          * @param User $user
 119          * @param bool $fromReplica Whether to check the replica DB first.
 120          *  To improve performance, non-critical checks are done against replica DBs.
 121          *  Check when actually saving should be done against master.
 122          * @return AbstractBlock|null The most relevant block, or null if there is no block.
 123          */
 124         public function getUserBlock( User $user, $fromReplica ) {
 125                 $isAnon = $user->getId() === 0;
 126
 127                 // TODO: If $user is the current user, we should use the current request. Otherwise,
 128                 // we should not look for XFF or cookie blocks.
 129                 $request = $user->getRequest();
 130
 131                 # We only need to worry about passing the IP address to the block generator if the
 132                 # user is not immune to autoblocks/hardblocks, and they are the current user so we
 133                 # know which IP address they're actually coming from
 134                 $ip = null;
 135                 $sessionUser = $this->currentUser;
 136                 // the session user is set up towards the end of Setup.php. Until then,
 137                 // assume it's a logged-out user.
 138                 $globalUserName = $sessionUser->isSafeToLoad()
 139                         ? $sessionUser->getName()
 140                         : IP::sanitizeIP( $this->currentRequest->getIP() );
 141                 if ( $user->getName() === $globalUserName && !$user->isAllowed( 'ipblock-exempt' ) ) {
 142                         $ip = $this->currentRequest->getIP();
 143                 }
 144
 145                 // User/IP blocking
 146                 // TODO: remove dependency on DatabaseBlock
 147                 $block = DatabaseBlock::newFromTarget( $user, $ip, !$fromReplica );
 148
 149                 // Cookie blocking
 150                 if ( !$block instanceof AbstractBlock ) {
 151                         $block = $this->getBlockFromCookieValue( $user, $request );
 152                 }
 153
 154                 // Proxy blocking
 155                 if ( !$block instanceof AbstractBlock
 156                         && $ip !== null
 157                         && !in_array( $ip, $this->proxyWhitelist )
 158                 ) {
 159                         // Local list
 160                         if ( $this->isLocallyBlockedProxy( $ip ) ) {
 161                                 $block = new SystemBlock( [
 162                                         'byText' => wfMessage( 'proxyblocker' )->text(),
 163                                         'reason' => wfMessage( 'proxyblockreason' )->plain(),
 164                                         'address' => $ip,
 165                                         'systemBlock' => 'proxy',
 166                                 ] );
 167                         } elseif ( $isAnon && $this->isDnsBlacklisted( $ip ) ) {
 168                                 $block = new SystemBlock( [
 169                                         'byText' => wfMessage( 'sorbs' )->text(),
 170                                         'reason' => wfMessage( 'sorbsreason' )->plain(),
 171                                         'address' => $ip,
 172                                         'systemBlock' => 'dnsbl',
 173                                 ] );
 174                         }
 175                 }
 176
 177                 // (T25343) Apply IP blocks to the contents of XFF headers, if enabled
 178                 if ( !$block instanceof AbstractBlock
 179                         && $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                         // TODO: remove dependency on DatabaseBlock
 189                         $block = DatabaseBlock::chooseBlock( $xffblocks, $xff );
 190                         if ( $block instanceof AbstractBlock ) {
 191                                 # Mangle the reason to alert the user that the block
 192                                 # originated from matching the X-Forwarded-For header.
 193                                 $block->setReason( wfMessage( 'xffblockreason', $block->getReason() )->plain() );
 194                         }
 195                 }
 196
 197                 if ( !$block instanceof AbstractBlock
 198                         && $ip !== null
 199                         && $isAnon
 200                         && IP::isInRanges( $ip, $this->softBlockRanges )
 201                 ) {
 202                         $block = new SystemBlock( [
 203                                 'address' => $ip,
 204                                 'byText' => 'MediaWiki default',
 205                                 'reason' => wfMessage( 'softblockrangesreason', $ip )->plain(),
 206                                 'anonOnly' => true,
 207                                 'systemBlock' => 'wgSoftBlockRanges',
 208                         ] );
 209                 }
 210
 211                 return $block;
 212         }
 213
 214         /**
 215          * Try to load a block from an ID given in a cookie value.
 216          *
 217          * @param UserIdentity $user
 218          * @param WebRequest $request
 219          * @return DatabaseBlock|bool The block object, or false if none could be loaded.
 220          */
 221         private function getBlockFromCookieValue(
 222                 UserIdentity $user,
 223                 WebRequest $request
 224         ) {
 225                 $blockCookieVal = $request->getCookie( 'BlockID' );
 226                 $response = $request->response();
 227
 228                 // Make sure there's something to check. The cookie value must start with a number.
 229                 if ( strlen( $blockCookieVal ) < 1 || !is_numeric( substr( $blockCookieVal, 0, 1 ) ) ) {
 230                         return false;
 231                 }
 232                 // Load the block from the ID in the cookie.
 233                 $blockCookieId = $this->getIdFromCookieValue( $blockCookieVal );
 234                 if ( $blockCookieId !== null ) {
 235                         // An ID was found in the cookie.
 236                         // TODO: remove dependency on DatabaseBlock
 237                         $tmpBlock = DatabaseBlock::newFromID( $blockCookieId );
 238                         if ( $tmpBlock instanceof DatabaseBlock ) {
 239                                 switch ( $tmpBlock->getType() ) {
 240                                         case DatabaseBlock::TYPE_USER:
 241                                                 $blockIsValid = !$tmpBlock->isExpired() && $tmpBlock->isAutoblocking();
 242                                                 $useBlockCookie = ( $this->cookieSetOnAutoblock === true );
 243                                                 break;
 244                                         case DatabaseBlock::TYPE_IP:
 245                                         case DatabaseBlock::TYPE_RANGE:
 246                                                 // If block is type IP or IP range, load only if user is not logged in (T152462)
 247                                                 $blockIsValid = !$tmpBlock->isExpired() && $user->getId() === 0;
 248                                                 $useBlockCookie = ( $this->cookieSetOnIpBlock === true );
 249                                                 break;
 250                                         default:
 251                                                 $blockIsValid = false;
 252                                                 $useBlockCookie = false;
 253                                 }
 254
 255                                 if ( $blockIsValid && $useBlockCookie ) {
 256                                         // Use the block.
 257                                         return $tmpBlock;
 258                                 }
 259                         }
 260                         // If the block is invalid or doesn't exist, remove the cookie.
 261                         $this->clearBlockCookie( $response );
 262                 }
 263                 return false;
 264         }
 265
 266         /**
 267          * Check if an IP address is in the local proxy list
 268          *
 269          * @param string $ip
 270          * @return bool
 271          */
 272         private function isLocallyBlockedProxy( $ip ) {
 273                 if ( !$this->proxyList ) {
 274                         return false;
 275                 }
 276
 277                 if ( !is_array( $this->proxyList ) ) {
 278                         // Load values from the specified file
 279                         $this->proxyList = array_map( 'trim', file( $this->proxyList ) );
 280                 }
 281
 282                 $resultProxyList = [];
 283                 $deprecatedIPEntries = [];
 284
 285                 // backward compatibility: move all ip addresses in keys to values
 286                 foreach ( $this->proxyList as $key => $value ) {
 287                         $keyIsIP = IP::isIPAddress( $key );
 288                         $valueIsIP = IP::isIPAddress( $value );
 289                         if ( $keyIsIP && !$valueIsIP ) {
 290                                 $deprecatedIPEntries[] = $key;
 291                                 $resultProxyList[] = $key;
 292                         } elseif ( $keyIsIP && $valueIsIP ) {
 293                                 $deprecatedIPEntries[] = $key;
 294                                 $resultProxyList[] = $key;
 295                                 $resultProxyList[] = $value;
 296                         } else {
 297                                 $resultProxyList[] = $value;
 298                         }
 299                 }
 300
 301                 if ( $deprecatedIPEntries ) {
 302                         wfDeprecated(
 303                                 'IP addresses in the keys of $wgProxyList (found the following IP addresses in keys: ' .
 304                                 implode( ', ', $deprecatedIPEntries ) . ', please move them to values)', '1.30' );
 305                 }
 306
 307                 $proxyListIPSet = new IPSet( $resultProxyList );
 308                 return $proxyListIPSet->match( $ip );
 309         }
 310
 311         /**
 312          * Whether the given IP is in a DNS blacklist.
 313          *
 314          * @param string $ip IP to check
 315          * @param bool $checkWhitelist Whether to check the whitelist first
 316          * @return bool True if blacklisted.
 317          */
 318         public function isDnsBlacklisted( $ip, $checkWhitelist = false ) {
 319                 if ( !$this->enableDnsBlacklist ||
 320                         ( $checkWhitelist && in_array( $ip, $this->proxyWhitelist ) )
 321                 ) {
 322                         return false;
 323                 }
 324
 325                 return $this->inDnsBlacklist( $ip, $this->dnsBlacklistUrls );
 326         }
 327
 328         /**
 329          * Whether the given IP is in a given DNS blacklist.
 330          *
 331          * @param string $ip IP to check
 332          * @param array $bases Array of Strings: URL of the DNS blacklist
 333          * @return bool True if blacklisted.
 334          */
 335         private function inDnsBlacklist( $ip, array $bases ) {
 336                 $found = false;
 337                 // @todo FIXME: IPv6 ???  (https://bugs.php.net/bug.php?id=33170)
 338                 if ( IP::isIPv4( $ip ) ) {
 339                         // Reverse IP, T23255
 340                         $ipReversed = implode( '.', array_reverse( explode( '.', $ip ) ) );
 341
 342                         foreach ( $bases as $base ) {
 343                                 // Make hostname
 344                                 // If we have an access key, use that too (ProjectHoneypot, etc.)
 345                                 $basename = $base;
 346                                 if ( is_array( $base ) ) {
 347                                         if ( count( $base ) >= 2 ) {
 348                                                 // Access key is 1, base URL is 0
 349                                                 $hostname = "{$base[1]}.$ipReversed.{$base[0]}";
 350                                         } else {
 351                                                 $hostname = "$ipReversed.{$base[0]}";
 352                                         }
 353                                         $basename = $base[0];
 354                                 } else {
 355                                         $hostname = "$ipReversed.$base";
 356                                 }
 357
 358                                 // Send query
 359                                 $ipList = $this->checkHost( $hostname );
 360
 361                                 if ( $ipList ) {
 362                                         wfDebugLog(
 363                                                 'dnsblacklist',
 364                                                 "Hostname $hostname is {$ipList[0]}, it's a proxy says $basename!"
 365                                         );
 366                                         $found = true;
 367                                         break;
 368                                 }
 369
 370                                 wfDebugLog( 'dnsblacklist', "Requested $hostname, not found in $basename." );
 371                         }
 372                 }
 373
 374                 return $found;
 375         }
 376
 377         /**
 378          * Wrapper for mocking in tests.
 379          *
 380          * @param string $hostname DNSBL query
 381          * @return string[]|bool IPv4 array, or false if the IP is not blacklisted
 382          */
 383         protected function checkHost( $hostname ) {
 384                 return gethostbynamel( $hostname );
 385         }
 386
 387         /**
 388          * Set the 'BlockID' cookie depending on block type and user authentication status.
 389          *
 390          * @since 1.34
 391          * @param User $user
 392          */
 393         public function trackBlockWithCookie( User $user ) {
 394                 $block = $user->getBlock();
 395                 $request = $user->getRequest();
 396
 397                 if (
 398                         $block &&
 399                         $request->getCookie( 'BlockID' ) === null &&
 400                         $this->shouldTrackBlockWithCookie( $block, $user->isAnon() )
 401                 ) {
 402                         $this->setBlockCookie( $block, $request->response() );
 403                 }
 404         }
 405
 406         /**
 407          * Set the 'BlockID' cookie to this block's ID and expiry time. The cookie's expiry will be
 408          * the same as the block's, to a maximum of 24 hours.
 409          *
 410          * @since 1.34
 411          * @internal Should be private.
 412          *  Left public for backwards compatibility, until DatabaseBlock::setCookie is removed.
 413          * @param DatabaseBlock $block
 414          * @param WebResponse $response The response on which to set the cookie.
 415          */
 416         public function setBlockCookie( DatabaseBlock $block, WebResponse $response ) {
 417                 // Calculate the default expiry time.
 418                 $maxExpiryTime = wfTimestamp( TS_MW, wfTimestamp() + ( 24 * 60 * 60 ) );
 419
 420                 // Use the block's expiry time only if it's less than the default.
 421                 $expiryTime = $block->getExpiry();
 422                 if ( $expiryTime === 'infinity' || $expiryTime > $maxExpiryTime ) {
 423                         $expiryTime = $maxExpiryTime;
 424                 }
 425
 426                 // Set the cookie. Reformat the MediaWiki datetime as a Unix timestamp for the cookie.
 427                 $expiryValue = DateTime::createFromFormat( 'YmdHis', $expiryTime )->format( 'U' );
 428                 $cookieOptions = [ 'httpOnly' => false ];
 429                 $cookieValue = $this->getCookieValue( $block );
 430                 $response->setCookie( 'BlockID', $cookieValue, $expiryValue, $cookieOptions );
 431         }
 432
 433         /**
 434          * Check if the block should be tracked with a cookie.
 435          *
 436          * @param AbstractBlock $block
 437          * @param bool $isAnon The user is logged out
 438          * @return bool The block sould be tracked with a cookie
 439          */
 440         private function shouldTrackBlockWithCookie( AbstractBlock $block, $isAnon ) {
 441                 if ( $block instanceof DatabaseBlock ) {
 442                         switch ( $block->getType() ) {
 443                                 case DatabaseBlock::TYPE_IP:
 444                                 case DatabaseBlock::TYPE_RANGE:
 445                                         return $isAnon && $this->cookieSetOnIpBlock;
 446                                 case DatabaseBlock::TYPE_USER:
 447                                         return !$isAnon && $this->cookieSetOnAutoblock && $block->isAutoblocking();
 448                                 default:
 449                                         return false;
 450                         }
 451                 }
 452                 return false;
 453         }
 454
 455         /**
 456          * Unset the 'BlockID' cookie.
 457          *
 458          * @since 1.34
 459          * @param WebResponse $response
 460          */
 461         public static function clearBlockCookie( WebResponse $response ) {
 462                 $response->clearCookie( 'BlockID', [ 'httpOnly' => false ] );
 463         }
 464
 465         /**
 466          * Get the stored ID from the 'BlockID' cookie. The cookie's value is usually a combination of
 467          * the ID and a HMAC (see DatabaseBlock::setCookie), but will sometimes only be the ID.
 468          *
 469          * @since 1.34
 470          * @internal Should be private.
 471          *  Left public for backwards compatibility, until DatabaseBlock::getIdFromCookieValue is removed.
 472          * @param string $cookieValue The string in which to find the ID.
 473          * @return int|null The block ID, or null if the HMAC is present and invalid.
 474          */
 475         public function getIdFromCookieValue( $cookieValue ) {
 476                 // Extract the ID prefix from the cookie value (may be the whole value, if no bang found).
 477                 $bangPos = strpos( $cookieValue, '!' );
 478                 $id = ( $bangPos === false ) ? $cookieValue : substr( $cookieValue, 0, $bangPos );
 479                 if ( !$this->secretKey ) {
 480                         // If there's no secret key, just use the ID as given.
 481                         return $id;
 482                 }
 483                 $storedHmac = substr( $cookieValue, $bangPos + 1 );
 484                 $calculatedHmac = MWCryptHash::hmac( $id, $this->secretKey, false );
 485                 if ( $calculatedHmac === $storedHmac ) {
 486                         return $id;
 487                 } else {
 488                         return null;
 489                 }
 490         }
 491
 492         /**
 493          * Get the BlockID cookie's value for this block. This is usually the block ID concatenated
 494          * with an HMAC in order to avoid spoofing (T152951), but if wgSecretKey is not set will just
 495          * be the block ID.
 496          *
 497          * @since 1.34
 498          * @internal Should be private.
 499          *  Left public for backwards compatibility, until DatabaseBlock::getCookieValue is removed.
 500          * @param DatabaseBlock $block
 501          * @return string The block ID, probably concatenated with "!" and the HMAC.
 502          */
 503         public function getCookieValue( DatabaseBlock $block ) {
 504                 $id = $block->getId();
 505                 if ( !$this->secretKey ) {
 506                         // If there's no secret key, don't append a HMAC.
 507                         return $id;
 508                 }
 509                 $hmac = MWCryptHash::hmac( $id, $this->secretKey, false );
 510                 $cookieValue = $id . '!' . $hmac;
 511                 return $cookieValue;
 512         }
 513
 514 }