includes/Block.php

   1 <?php
   2 /**
   3  * Blocks and bans object
   4  */
   5
   6 /**
   7  * The block class
   8  * All the functions in this class assume the object is either explicitly
   9  * loaded or filled. It is not load-on-demand. There are no accessors.
  10  *
  11  * Globals used: $wgAutoblockExpiry, $wgAntiLockFlags
  12  *
  13  * @todo This could be used everywhere, but it isn't.
  14  */
  15 class Block
  16 {
  17         /* public*/ var $mAddress, $mUser, $mBy, $mReason, $mTimestamp, $mAuto, $mId, $mExpiry,
  18                             $mRangeStart, $mRangeEnd, $mAnonOnly, $mEnableAutoblock;
  19         /* private */ var $mNetworkBits, $mIntegerAddr, $mForUpdate, $mFromMaster, $mByName;
  20
  21         const EB_KEEP_EXPIRED = 1;
  22         const EB_FOR_UPDATE = 2;
  23         const EB_RANGE_ONLY = 4;
  24
  25         function __construct( $address = '', $user = 0, $by = 0, $reason = '',
  26                 $timestamp = '' , $auto = 0, $expiry = '', $anonOnly = 0, $createAccount = 0, $enableAutoblock = 0 )
  27         {
  28                 $this->mId = 0;
  29                 $this->mAddress = $address;
  30                 $this->mUser = $user;
  31                 $this->mBy = $by;
  32                 $this->mReason = $reason;
  33                 $this->mTimestamp = wfTimestamp(TS_MW,$timestamp);
  34                 $this->mAuto = $auto;
  35                 $this->mAnonOnly = $anonOnly;
  36                 $this->mCreateAccount = $createAccount;
  37                 $this->mExpiry = self::decodeExpiry( $expiry );
  38                 $this->mEnableAutoblock = $enableAutoblock;
  39
  40                 $this->mForUpdate = false;
  41                 $this->mFromMaster = false;
  42                 $this->mByName = false;
  43                 $this->initialiseRange();
  44         }
  45
  46         static function newFromDB( $address, $user = 0, $killExpired = true )
  47         {
  48                 $block = new Block();
  49                 $block->load( $address, $user, $killExpired );
  50                 if ( $block->isValid() ) {
  51                         return $block;
  52                 } else {
  53                         return null;
  54                 }
  55         }
  56
  57         static function newFromID( $id )
  58         {
  59                 $dbr =& wfGetDB( DB_SLAVE );
  60                 $res = $dbr->resultObject( $dbr->select( 'ipblocks', '*',
  61                         array( 'ipb_id' => $id ), __METHOD__ ) );
  62                 $block = new Block;
  63                 if ( $block->loadFromResult( $res ) ) {
  64                         return $block;
  65                 } else {
  66                         return null;
  67                 }
  68         }
  69
  70         function clear()
  71         {
  72                 $this->mAddress = $this->mReason = $this->mTimestamp = '';
  73                 $this->mId = $this->mAnonOnly = $this->mCreateAccount =
  74                         $this->mEnableAutoblock = $this->mAuto = $this->mUser =
  75                         $this->mBy = 0;
  76                 $this->mByName = false;
  77         }
  78
  79         /**
  80          * Get the DB object and set the reference parameter to the query options
  81          */
  82         function &getDBOptions( &$options )
  83         {
  84                 global $wgAntiLockFlags;
  85                 if ( $this->mForUpdate || $this->mFromMaster ) {
  86                         $db =& wfGetDB( DB_MASTER );
  87                         if ( !$this->mForUpdate || ($wgAntiLockFlags & ALF_NO_BLOCK_LOCK) ) {
  88                                 $options = array();
  89                         } else {
  90                                 $options = array( 'FOR UPDATE' );
  91                         }
  92                 } else {
  93                         $db =& wfGetDB( DB_SLAVE );
  94                         $options = array();
  95                 }
  96                 return $db;
  97         }
  98
  99         /**
 100          * Get a ban from the DB, with either the given address or the given username
 101          *
 102          * @param string $address The IP address of the user, or blank to skip IP blocks
 103          * @param integer $user The user ID, or zero for anonymous users
 104          * @param bool $killExpired Whether to delete expired rows while loading
 105          *
 106          */
 107         function load( $address = '', $user = 0, $killExpired = true )
 108         {
 109                 wfDebug( "Block::load: '$address', '$user', $killExpired\n" );
 110
 111                 $options = array();
 112                 $db =& $this->getDBOptions( $options );
 113
 114                 if ( 0 == $user && $address == '' ) {
 115                         # Invalid user specification, not blocked
 116                         $this->clear();
 117                         return false;
 118                 }
 119
 120                 # Try user block
 121                 if ( $user ) {
 122                         $res = $db->resultObject( $db->select( 'ipblocks', '*', array( 'ipb_user' => $user ),
 123                                 __METHOD__, $options ) );
 124                         if ( $this->loadFromResult( $res, $killExpired ) ) {
 125                                 return true;
 126                         }
 127                 }
 128
 129                 # Try IP block
 130                 # TODO: improve performance by merging this query with the autoblock one
 131                 # Slightly tricky while handling killExpired as well
 132                 if ( $address ) {
 133                         $conds = array( 'ipb_address' => $address, 'ipb_auto' => 0 );
 134                         $res = $db->resultObject( $db->select( 'ipblocks', '*', $conds, __METHOD__, $options ) );
 135                         if ( $this->loadFromResult( $res, $killExpired ) ) {
 136                                 if ( $user && $this->mAnonOnly ) {
 137                                         # Block is marked anon-only
 138                                         # Whitelist this IP address against autoblocks and range blocks
 139                                         $this->clear();
 140                                         return false;
 141                                 } else {
 142                                         return true;
 143                                 }
 144                         }
 145                 }
 146
 147                 # Try range block
 148                 if ( $this->loadRange( $address, $killExpired, $user == 0 ) ) {
 149                         if ( $user && $this->mAnonOnly ) {
 150                                 $this->clear();
 151                                 return false;
 152                         } else {
 153                                 return true;
 154                         }
 155                 }
 156
 157                 # Try autoblock
 158                 if ( $address ) {
 159                         $conds = array( 'ipb_address' => $address, 'ipb_auto' => 1 );
 160                         if ( $user ) {
 161                                 $conds['ipb_anon_only'] = 0;
 162                         }
 163                         $res = $db->resultObject( $db->select( 'ipblocks', '*', $conds, __METHOD__, $options ) );
 164                         if ( $this->loadFromResult( $res, $killExpired ) ) {
 165                                 return true;
 166                         }
 167                 }
 168
 169                 # Give up
 170                 $this->clear();
 171                 return false;
 172         }
 173
 174         /**
 175          * Fill in member variables from a result wrapper
 176          */
 177         function loadFromResult( ResultWrapper $res, $killExpired = true ) {
 178                 $ret = false;
 179                 if ( 0 != $res->numRows() ) {
 180                         # Get first block
 181                         $row = $res->fetchObject();
 182                         $this->initFromRow( $row );
 183
 184                         if ( $killExpired ) {
 185                                 # If requested, delete expired rows
 186                                 do {
 187                                         $killed = $this->deleteIfExpired();
 188                                         if ( $killed ) {
 189                                                 $row = $res->fetchObject();
 190                                                 if ( $row ) {
 191                                                         $this->initFromRow( $row );
 192                                                 }
 193                                         }
 194                                 } while ( $killed && $row );
 195
 196                                 # If there were any left after the killing finished, return true
 197                                 if ( $row ) {
 198                                         $ret = true;
 199                                 }
 200                         } else {
 201                                 $ret = true;
 202                         }
 203                 }
 204                 $res->free();
 205                 return $ret;
 206         }
 207
 208         /**
 209          * Search the database for any range blocks matching the given address, and
 210          * load the row if one is found.
 211          */
 212         function loadRange( $address, $killExpired = true )
 213         {
 214                 $iaddr = IP::toHex( $address );
 215                 if ( $iaddr === false ) {
 216                         # Invalid address
 217                         return false;
 218                 }
 219
 220                 # Only scan ranges which start in this /16, this improves search speed
 221                 # Blocks should not cross a /16 boundary.
 222                 $range = substr( $iaddr, 0, 4 );
 223
 224                 $options = array();
 225                 $db =& $this->getDBOptions( $options );
 226                 $conds = array(
 227                         "ipb_range_start LIKE '$range%'",
 228                         "ipb_range_start <= '$iaddr'",
 229                         "ipb_range_end >= '$iaddr'"
 230                 );
 231
 232                 $res = $db->resultObject( $db->select( 'ipblocks', '*', $conds, __METHOD__, $options ) );
 233                 $success = $this->loadFromResult( $res, $killExpired );
 234                 return $success;
 235         }
 236
 237         /**
 238          * Determine if a given integer IPv4 address is in a given CIDR network
 239          * @deprecated Use IP::isInRange
 240          */
 241         function isAddressInRange( $addr, $range ) {
 242                 return IP::isInRange( $addr, $range );
 243         }
 244
 245         function initFromRow( $row )
 246         {
 247                 $this->mAddress = $row->ipb_address;
 248                 $this->mReason = $row->ipb_reason;
 249                 $this->mTimestamp = wfTimestamp(TS_MW,$row->ipb_timestamp);
 250                 $this->mUser = $row->ipb_user;
 251                 $this->mBy = $row->ipb_by;
 252                 $this->mAuto = $row->ipb_auto;
 253                 $this->mAnonOnly = $row->ipb_anon_only;
 254                 $this->mCreateAccount = $row->ipb_create_account;
 255                 $this->mEnableAutoblock = $row->ipb_enable_autoblock;
 256                 $this->mId = $row->ipb_id;
 257                 $this->mExpiry = self::decodeExpiry( $row->ipb_expiry );
 258                 if ( isset( $row->user_name ) ) {
 259                         $this->mByName = $row->user_name;
 260                 } else {
 261                         $this->mByName = false;
 262                 }
 263                 $this->mRangeStart = $row->ipb_range_start;
 264                 $this->mRangeEnd = $row->ipb_range_end;
 265         }
 266
 267         function initialiseRange()
 268         {
 269                 $this->mRangeStart = '';
 270                 $this->mRangeEnd = '';
 271
 272                 if ( $this->mUser == 0 ) {
 273                         list( $this->mRangeStart, $this->mRangeEnd ) = IP::parseRange( $this->mAddress );
 274                 }
 275         }
 276
 277         /**
 278          * Callback with a Block object for every block
 279          * @return integer number of blocks;
 280          */
 281         /*static*/ function enumBlocks( $callback, $tag, $flags = 0 )
 282         {
 283                 global $wgAntiLockFlags;
 284
 285                 $block = new Block();
 286                 if ( $flags & Block::EB_FOR_UPDATE ) {
 287                         $db =& wfGetDB( DB_MASTER );
 288                         if ( $wgAntiLockFlags & ALF_NO_BLOCK_LOCK ) {
 289                                 $options = '';
 290                         } else {
 291                                 $options = 'FOR UPDATE';
 292                         }
 293                         $block->forUpdate( true );
 294                 } else {
 295                         $db =& wfGetDB( DB_SLAVE );
 296                         $options = '';
 297                 }
 298                 if ( $flags & Block::EB_RANGE_ONLY ) {
 299                         $cond = " AND ipb_range_start <> ''";
 300                 } else {
 301                         $cond = '';
 302                 }
 303
 304                 $now = wfTimestampNow();
 305
 306                 list( $ipblocks, $user ) = $db->tableNamesN( 'ipblocks', 'user' );
 307
 308                 $sql = "SELECT $ipblocks.*,user_name FROM $ipblocks,$user " .
 309                         "WHERE user_id=ipb_by $cond ORDER BY ipb_timestamp DESC $options";
 310                 $res = $db->query( $sql, 'Block::enumBlocks' );
 311                 $num_rows = $db->numRows( $res );
 312
 313                 while ( $row = $db->fetchObject( $res ) ) {
 314                         $block->initFromRow( $row );
 315                         if ( ( $flags & Block::EB_RANGE_ONLY ) && $block->mRangeStart == '' ) {
 316                                 continue;
 317                         }
 318
 319                         if ( !( $flags & Block::EB_KEEP_EXPIRED ) ) {
 320                                 if ( $block->mExpiry && $now > $block->mExpiry ) {
 321                                         $block->delete();
 322                                 } else {
 323                                         call_user_func( $callback, $block, $tag );
 324                                 }
 325                         } else {
 326                                 call_user_func( $callback, $block, $tag );
 327                         }
 328                 }
 329                 $db->freeResult( $res );
 330                 return $num_rows;
 331         }
 332
 333         function delete()
 334         {
 335                 if (wfReadOnly()) {
 336                         return false;
 337                 }
 338                 if ( !$this->mId ) {
 339                         throw new MWException( "Block::delete() now requires that the mId member be filled\n" );
 340                 }
 341
 342                 $dbw =& wfGetDB( DB_MASTER );
 343                 $dbw->delete( 'ipblocks', array( 'ipb_id' => $this->mId ), __METHOD__ );
 344                 return $dbw->affectedRows() > 0;
 345         }
 346
 347         /**
 348         * Insert a block into the block table.
 349         *@return Whether or not the insertion was successful.
 350         */
 351         function insert()
 352         {
 353                 wfDebug( "Block::insert; timestamp {$this->mTimestamp}\n" );
 354                 $dbw =& wfGetDB( DB_MASTER );
 355                 $dbw->begin();
 356
 357                 # Unset ipb_anon_only for user blocks, makes no sense
 358                 if ( $this->mUser ) {
 359                         $this->mAnonOnly = 0;
 360                 }
 361
 362                 # Unset ipb_enable_autoblock for IP blocks, makes no sense
 363                 if ( !$this->mUser ) {
 364                         $this->mEnableAutoblock = 0;
 365                 }
 366
 367                 # Don't collide with expired blocks
 368                 Block::purgeExpired();
 369
 370                 $ipb_id = $dbw->nextSequenceValue('ipblocks_ipb_id_val');
 371                 $dbw->insert( 'ipblocks',
 372                         array(
 373                                 'ipb_id' => $ipb_id,
 374                                 'ipb_address' => $this->mAddress,
 375                                 'ipb_user' => $this->mUser,
 376                                 'ipb_by' => $this->mBy,
 377                                 'ipb_reason' => $this->mReason,
 378                                 'ipb_timestamp' => $dbw->timestamp($this->mTimestamp),
 379                                 'ipb_auto' => $this->mAuto,
 380                                 'ipb_anon_only' => $this->mAnonOnly,
 381                                 'ipb_create_account' => $this->mCreateAccount,
 382                                 'ipb_enable_autoblock' => $this->mEnableAutoblock,
 383                                 'ipb_expiry' => self::encodeExpiry( $this->mExpiry, $dbw ),
 384                                 'ipb_range_start' => $this->mRangeStart,
 385                                 'ipb_range_end' => $this->mRangeEnd,
 386                         ), 'Block::insert', array( 'IGNORE' )
 387                 );
 388                 $affected = $dbw->affectedRows();
 389                 $dbw->commit();
 390
 391                 if ($affected)
 392                         $this->doRetroactiveAutoblock();
 393
 394                 return $affected;
 395         }
 396
 397         /**
 398         * Retroactively autoblocks the last IP used by the user (if it is a user)
 399         * blocked by this Block.
 400         *@return Whether or not a retroactive autoblock was made.
 401         */
 402         function doRetroactiveAutoblock() {
 403                 $dbr = wfGetDB( DB_SLAVE );
 404                 #If autoblock is enabled, autoblock the LAST IP used
 405                 # - stolen shamelessly from CheckUser_body.php
 406
 407                 if ($this->mEnableAutoblock && $this->mUser) {
 408                         wfDebug("Doing retroactive autoblocks for " . $this->mAddress . "\n");
 409
 410                         $row = $dbr->selectRow( 'recentchanges', array( 'rc_ip' ), array( 'rc_user_text' => $this->mAddress ),
 411                                 __METHOD__ , array( 'ORDER BY' => 'rc_timestamp DESC' ) );
 412
 413                         if ( !$row || !$row->rc_ip ) {
 414                                 #No results, don't autoblock anything
 415                                 wfDebug("No IP found to retroactively autoblock\n");
 416                         } else {
 417                                 #Limit is 1, so no loop needed.
 418                                 $retroblockip = $row->rc_ip;
 419                                 return $this->doAutoblock($retroblockip);
 420                         }
 421                 }
 422         }
 423
 424         /**
 425         * Autoblocks the given IP, referring to this Block.
 426         * @param $autoblockip The IP to autoblock.
 427         * @return bool Whether or not an autoblock was inserted.
 428         */
 429         function doAutoblock( $autoblockip ) {
 430                 # Check if this IP address is already blocked
 431                 $dbw =& wfGetDB( DB_MASTER );
 432                 $dbw->begin();
 433
 434                 # If autoblocks are disabled, go away.
 435                 if ( !$this->mEnableAutoblock ) {
 436                         return;
 437                 }
 438
 439                 # Check for presence on the autoblock whitelist
 440                 # TODO cache this?
 441                 $lines = explode( "\n", wfMsgForContentNoTrans( 'autoblock_whitelist' ) );
 442
 443                 $ip = $autoblockip;
 444
 445                 wfDebug("Checking the autoblock whitelist..\n");
 446
 447                 foreach( $lines as $line ) {
 448                         # List items only
 449                         if ( substr( $line, 0, 1 ) !== '*' ) {
 450                                 continue;
 451                         }
 452
 453                         $wlEntry = substr($line, 1);
 454                         $wlEntry = trim($wlEntry);
 455
 456                         wfDebug("Checking $ip against $wlEntry...");
 457
 458                         # Is the IP in this range?
 459                         if (IP::isInRange( $ip, $wlEntry )) {
 460                                 wfDebug(" IP $ip matches $wlEntry, not autoblocking\n");
 461                                 #$autoblockip = null; # Don't autoblock a whitelisted IP.
 462                                 return; #This /SHOULD/ introduce a dummy block - but
 463                                         # I don't know a safe way to do so. -werdna
 464                         } else {
 465                                 wfDebug( " No match\n" );
 466                         }
 467                 }
 468
 469                 # It's okay to autoblock. Go ahead and create/insert the block.
 470
 471                 $ipblock = Block::newFromDB( $autoblockip );
 472                 if ( $ipblock ) {
 473                         # If the user is already blocked. Then check if the autoblock would
 474                         # exceed the user block. If it would exceed, then do nothing, else
 475                         # prolong block time
 476                         if ($this->mExpiry &&
 477                         ($this->mExpiry < Block::getAutoblockExpiry($ipblock->mTimestamp))) {
 478                                 return;
 479                         }
 480                         # Just update the timestamp
 481                         $ipblock->updateTimestamp();
 482                         return;
 483                 } else {
 484                         $ipblock = new Block;
 485                 }
 486
 487                 # Make a new block object with the desired properties
 488                 wfDebug( "Autoblocking {$this->mAddress}@" . $autoblockip . "\n" );
 489                 $ipblock->mAddress = $autoblockip;
 490                 $ipblock->mUser = 0;
 491                 $ipblock->mBy = $this->mBy;
 492                 $ipblock->mReason = wfMsgForContent( 'autoblocker', $this->mAddress, $this->mReason );
 493                 $ipblock->mTimestamp = wfTimestampNow();
 494                 $ipblock->mAuto = 1;
 495                 $ipblock->mCreateAccount = $this->mCreateAccount;
 496
 497                 # If the user is already blocked with an expiry date, we don't
 498                 # want to pile on top of that!
 499                 if($this->mExpiry) {
 500                         $ipblock->mExpiry = min ( $this->mExpiry, Block::getAutoblockExpiry( $this->mTimestamp ));
 501                 } else {
 502                         $ipblock->mExpiry = Block::getAutoblockExpiry( $this->mTimestamp );
 503                 }
 504                 # Insert it
 505                 return $ipblock->insert();
 506         }
 507
 508         function deleteIfExpired()
 509         {
 510                 $fname = 'Block::deleteIfExpired';
 511                 wfProfileIn( $fname );
 512                 if ( $this->isExpired() ) {
 513                         wfDebug( "Block::deleteIfExpired() -- deleting\n" );
 514                         $this->delete();
 515                         $retVal = true;
 516                 } else {
 517                         wfDebug( "Block::deleteIfExpired() -- not expired\n" );
 518                         $retVal = false;
 519                 }
 520                 wfProfileOut( $fname );
 521                 return $retVal;
 522         }
 523
 524         function isExpired()
 525         {
 526                 wfDebug( "Block::isExpired() checking current " . wfTimestampNow() . " vs $this->mExpiry\n" );
 527                 if ( !$this->mExpiry ) {
 528                         return false;
 529                 } else {
 530                         return wfTimestampNow() > $this->mExpiry;
 531                 }
 532         }
 533
 534         function isValid()
 535         {
 536                 return $this->mAddress != '';
 537         }
 538
 539         function updateTimestamp()
 540         {
 541                 if ( $this->mAuto ) {
 542                         $this->mTimestamp = wfTimestamp();
 543                         $this->mExpiry = Block::getAutoblockExpiry( $this->mTimestamp );
 544
 545                         $dbw =& wfGetDB( DB_MASTER );
 546                         $dbw->update( 'ipblocks',
 547                                 array( /* SET */
 548                                         'ipb_timestamp' => $dbw->timestamp($this->mTimestamp),
 549                                         'ipb_expiry' => $dbw->timestamp($this->mExpiry),
 550                                 ), array( /* WHERE */
 551                                         'ipb_address' => $this->mAddress
 552                                 ), 'Block::updateTimestamp'
 553                         );
 554                 }
 555         }
 556
 557         /*
 558         function getIntegerAddr()
 559         {
 560                 return $this->mIntegerAddr;
 561         }
 562
 563         function getNetworkBits()
 564         {
 565                 return $this->mNetworkBits;
 566         }*/
 567
 568         /**
 569          * @return The blocker user ID.
 570          */
 571         public function getBy() {
 572                 return $this->mBy;
 573         }
 574
 575         /**
 576          * @return The blocker user name.
 577          */
 578         function getByName()
 579         {
 580                 if ( $this->mByName === false ) {
 581                         $this->mByName = User::whoIs( $this->mBy );
 582                 }
 583                 return $this->mByName;
 584         }
 585
 586         function forUpdate( $x = NULL ) {
 587                 return wfSetVar( $this->mForUpdate, $x );
 588         }
 589
 590         function fromMaster( $x = NULL ) {
 591                 return wfSetVar( $this->mFromMaster, $x );
 592         }
 593
 594         function getRedactedName() {
 595                 if ( $this->mAuto ) {
 596                         return '#' . $this->mId;
 597                 } else {
 598                         return $this->mAddress;
 599                 }
 600         }
 601
 602         /**
 603          * Encode expiry for DB
 604          */
 605         static function encodeExpiry( $expiry, $db ) {
 606                 if ( $expiry == '' || $expiry == Block::infinity() ) {
 607                         return Block::infinity();
 608                 } else {
 609                         return $db->timestamp( $expiry );
 610                 }
 611         }
 612
 613         /**
 614          * Decode expiry which has come from the DB
 615          */
 616         static function decodeExpiry( $expiry ) {
 617                 if ( $expiry == '' || $expiry == Block::infinity() ) {
 618                         return Block::infinity();
 619                 } else {
 620                         return wfTimestamp( TS_MW, $expiry );
 621                 }
 622         }
 623
 624         static function getAutoblockExpiry( $timestamp )
 625         {
 626                 global $wgAutoblockExpiry;
 627                 return wfTimestamp( TS_MW, wfTimestamp( TS_UNIX, $timestamp ) + $wgAutoblockExpiry );
 628         }
 629
 630         static function normaliseRange( $range )
 631         {
 632                 $parts = explode( '/', $range );
 633                 if ( count( $parts ) == 2 ) {
 634                         $shift = 32 - $parts[1];
 635                         $ipint = IP::toUnsigned( $parts[0] );
 636                         $ipint = $ipint >> $shift << $shift;
 637                         $newip = long2ip( $ipint );
 638                         $range = "$newip/{$parts[1]}";
 639                 }
 640                 return $range;
 641         }
 642
 643         /**
 644          * Purge expired blocks from the ipblocks table
 645          */
 646         static function purgeExpired() {
 647                 $dbw =& wfGetDB( DB_MASTER );
 648                 $dbw->delete( 'ipblocks', array( 'ipb_expiry < ' . $dbw->addQuotes( $dbw->timestamp() ) ), __METHOD__ );
 649         }
 650
 651         static function infinity() {
 652                 # This is a special keyword for timestamps in PostgreSQL, and
 653                 # works with CHAR(14) as well because "i" sorts after all numbers.
 654                 return 'infinity';
 655
 656                 /*
 657                 static $infinity;
 658                 if ( !isset( $infinity ) ) {
 659                         $dbr =& wfGetDB( DB_SLAVE );
 660                         $infinity = $dbr->bigTimestamp();
 661                 }
 662                 return $infinity;
 663                  */
 664         }
 665
 666 }
 667 ?>