Project: Joomla

Revision: 10151

Author: eddieajau

Date: 19 Mar 2008 07:00:49

• /development/trunk/libraries/joomla/filter/filterinput.php

  ......	@@ -1,496 +1,506 @@
  1		<?php
  2		/**
  3		* @version $Id$
  4		* @package Joomla.Framework
  5		* @subpackage Filter
  6		* @copyright Copyright (C) 2005 - 2008 Open Source Matters. All rights reserved.
  7		* @license GNU/GPL, see LICENSE.php
  8		* Joomla! is free software. This version may have been modified pursuant to the
  9		* GNU General Public License, and as distributed it includes or is derivative
  10		* of works licensed under the GNU General Public License or other free or open
  11		* source software licenses. See COPYRIGHT.php for copyright notices and
  12		* details.
  13		*/
  14
  15		// Check to ensure this file is within the rest of the framework
  16		defined('JPATH_BASE') or die();
  17
  18		/**
  19		* JFilterInput is a class for filtering input from any data source
  20		*
  21		* Forked from the php input filter library by: Daniel Morris <dan@rootcube.com>
  22		* Original Contributors: Gianpaolo Racca, Ghislain Picard, Marco Wandschneider, Chris Tobin and Andrew Eddie.
  23		*
  24		* @author Louis Landry <louis.landry@joomla.org>
  25		* @package Joomla.Framework
  26		* @subpackage Filter
  27		* @since 1.5
  28		*/
  29		class JFilterInput extends JObject
  30		{
  31		var $tagsArray; // default = empty array
  32		var $attrArray; // default = empty array
  33
  34		var $tagsMethod; // default = 0
  35		var $attrMethod; // default = 0
  36
  37		var $xssAuto; // default = 1
  38		var $tagBlacklist = array ('applet', 'body', 'bgsound', 'base', 'basefont', 'embed', 'frame', 'frameset', 'head', 'html', 'id', 'iframe', 'ilayer', 'layer', 'link', 'meta', 'name', 'object', 'script', 'style', 'title', 'xml');
  39		var $attrBlacklist = array ('action', 'background', 'codebase', 'dynsrc', 'lowsrc'); // also will strip ALL event handlers
  40
  41		/**
  42		* Constructor for inputFilter class. Only first parameter is required.
  43		*
  44		* @access protected
  45		* @param array $tagsArray list of user-defined tags
  46		* @param array $attrArray list of user-defined attributes
  47		* @param int $tagsMethod WhiteList method = 0, BlackList method = 1
  48		* @param int $attrMethod WhiteList method = 0, BlackList method = 1
  49		* @param int $xssAuto Only auto clean essentials = 0, Allow clean blacklisted tags/attr = 1
  50		* @since 1.5
  51		*/
  52		function __construct($tagsArray = array(), $attrArray = array(), $tagsMethod = 0, $attrMethod = 0, $xssAuto = 1)
  53		{
  54		// Make sure user defined arrays are in lowercase
  55		$tagsArray = array_map('strtolower', (array) $tagsArray);
  56		$attrArray = array_map('strtolower', (array) $attrArray);
  57
  58		// Assign member variables
  59		$this->tagsArray = $tagsArray;
  60		$this->attrArray = $attrArray;
  61		$this->tagsMethod = $tagsMethod;
  62		$this->attrMethod = $attrMethod;
  63		$this->xssAuto = $xssAuto;
  64		}
  65
  66		/**
  67		* Returns a reference to an input filter object, only creating it if it doesn't already exist.
  68		*
  69		* This method must be invoked as:
  70		* <pre> $filter = & JFilterInput::getInstance();</pre>
  71		*
  72		* @static
  73		* @param array $tagsArray list of user-defined tags
  74		* @param array $attrArray list of user-defined attributes
  75		* @param int $tagsMethod WhiteList method = 0, BlackList method = 1
  76		* @param int $attrMethod WhiteList method = 0, BlackList method = 1
  77		* @param int $xssAuto Only auto clean essentials = 0, Allow clean blacklisted tags/attr = 1
  78		* @return object The JFilterInput object.
  79		* @since 1.5
  80		*/
  81		function & getInstance($tagsArray = array(), $attrArray = array(), $tagsMethod = 0, $attrMethod = 0, $xssAuto = 1)
  82		{
  83		static $instances;
  84
  85		$sig = md5(serialize(array($tagsArray,$attrArray,$tagsMethod,$attrMethod,$xssAuto)));
  86
  87		if (!isset ($instances)) {
  88		$instances = array();
  89		}
  90
  91		if (empty ($instances[$sig])) {
  92		$instances[$sig] = new JFilterInput($tagsArray, $attrArray, $tagsMethod, $attrMethod, $xssAuto);
  93		}
  94
  95		return $instances[$sig];
  96		}
  97
  98		/**
  99		* Method to be called by another php script. Processes for XSS and
  100		* specified bad code.
  101		*
  102		* @access public
  103		* @param mixed $source Input string/array-of-string to be 'cleaned'
  104		* @param string $type Return type for the variable (INT, FLOAT, BOOLEAN, WORD, ALNUM, CMD, BASE64, STRING, ARRAY, PATH, NONE)
  105		* @return mixed 'Cleaned' version of input parameter
  106		* @since 1.5
  107		* @static
  108		*/
  109		function clean($source, $type='string')
  110		{
  111		// Handle the type constraint
  112		switch (strtoupper($type))
  113		{
  114		case 'INT' :
  115		case 'INTEGER' :
  116		// Only use the first integer value
  117		preg_match('/-?[0-9]+/', (string) $source, $matches);
  118		$result = @ (int) $matches[0];
  119		break;
  120
  121		case 'FLOAT' :
  122		case 'DOUBLE' :
  123		// Only use the first floating point value
  124		preg_match('/-?[0-9]+(\.[0-9]+)?/', (string) $source, $matches);
  125		$result = @ (float) $matches[0];
  126		break;
  127
  128		case 'BOOL' :
  129		case 'BOOLEAN' :
  130		$result = (bool) $source;
  131		break;
  132
  133		case 'WORD' :
  134		$result = (string) preg_replace( '/[^A-Z_]/i', '', $source );
  135		break;
  136
  137		case 'ALNUM' :
  138		$result = (string) preg_replace( '/[^A-Z0-9]/i', '', $source );
  139		break;
  140
  141		case 'CMD' :
  142		$result = (string) preg_replace( '/[^A-Z0-9_\.-]/i', '', $source );
  143		$result = ltrim($result, '.');
  144		break;
  145
  146		case 'BASE64' :
  147		$result = (string) preg_replace( '/[^A-Z0-9\/+=]/i', '', $source );
  148		break;
  149
  150		case 'STRING' :
  151		$filter = JFilterInput::getInstance();
  152		$result = (string) $filter->_remove($filter->_decode((string) $source));
  153		break;
  154
  155		case 'ARRAY' :
  156		$result = (array) $source;
  157		break;
  158
  159		case 'PATH' :
  160		$pattern = '/^[A-Za-z0-9_-]+[A-Za-z0-9_\.-]*([\\\\\/][A-Za-z0-9_-]+[A-Za-z0-9_\.-]*)*$/';
  161		preg_match($pattern, (string) $source, $matches);
  162		$result = @ (string) $matches[0];
  163		break;
  164
  165		case 'USERNAME' :
  166		$result = (string) preg_replace( '/[\x00-\x1F\x7F<>"\'%&]/', '', $source );
  167		break;
  168
  169		default :
  170		// Are we dealing with an array?
  171		$filter = JFilterInput::getInstance();
  172		if (is_array($source)) {
  173		foreach ($source as $key => $value)
  174		{
  175		// filter element for XSS and other 'bad' code etc.
  176		if (is_string($value)) {
  177		$source[$key] = $filter->_remove($filter->_decode($value));
  178		}
  179		}
  180		$result = $source;
  181		} else {
  182		// Or a string?
  183		if (is_string($source) && !empty ($source)) {
  184		// filter source for XSS and other 'bad' code etc.
  185		$result = $filter->_remove($filter->_decode($source));
  186		} else {
  187		// Not an array or string.. return the passed parameter
  188		$result = $source;
  189		}
  190		}
  191		break;
  192		}
  193		return $result;
  194		}
  195
  196		/**
  197		* Function to determine if contents of an attribute is safe
  198		*
  199		* @static
  200		* @param array $attrSubSet A 2 element array for attributes name,value
  201		* @return boolean True if bad code is detected
  202		* @since 1.5
  203		*/
  204		function checkAttribute($attrSubSet)
  205		{
  206		$attrSubSet[0] = strtolower($attrSubSet[0]);
  207		$attrSubSet[1] = strtolower($attrSubSet[1]);
  208		return (((strpos($attrSubSet[1], 'expression') !== false) && ($attrSubSet[0]) == 'style') || (strpos($attrSubSet[1], 'javascript:') !== false) || (strpos($attrSubSet[1], 'behaviour:') !== false) || (strpos($attrSubSet[1], 'vbscript:') !== false) || (strpos($attrSubSet[1], 'mocha:') !== false) || (strpos($attrSubSet[1], 'livescript:') !== false));
  209		}
  210
  211		/**
  212		* Internal method to iteratively remove all unwanted tags and attributes
  213		*
  214		* @access protected
  215		* @param string $source Input string to be 'cleaned'
  216		* @return string 'Cleaned' version of input parameter
  217		* @since 1.5
  218		*/
  219		function _remove($source)
  220		{
  221		$loopCounter = 0;
  222
  223		// Iteration provides nested tag protection
  224		while ($source != $this->_cleanTags($source))
  225		{
  226		$source = $this->_cleanTags($source);
  227		$loopCounter ++;
  228		}
  229		return $source;
  230		}
  231
  232		/**
  233		* Internal method to strip a string of certain tags
  234		*
  235		* @access protected
  236		* @param string $source Input string to be 'cleaned'
  237		* @return string 'Cleaned' version of input parameter
  238		* @since 1.5
  239		*/
  240		function _cleanTags($source)
  241		{
  242		/*
  243		* In the beginning we don't really have a tag, so everything is
  244		* postTag
  245		*/
  246		$preTag = null;
  247		$postTag = $source;
  248		$currentSpace = false;
  249		$attr = ''; // moffats: setting to null due to issues in migration system - undefined variable errors
  250
  251		// Is there a tag? If so it will certainly start with a '<'
  252		$tagOpen_start = strpos($source, '<');
  253
  254		while ($tagOpen_start !== false)
  255		{
  256		// Get some information about the tag we are processing
  257		$preTag .= substr($postTag, 0, $tagOpen_start);
  258		$postTag = substr($postTag, $tagOpen_start);
  259		$fromTagOpen = substr($postTag, 1);
  260		$tagOpen_end = strpos($fromTagOpen, '>');
  261
  262		// Let's catch any non-terminated tags and skip over them
  263		if ($tagOpen_end === false) {
  264		$postTag = substr($postTag, $tagOpen_start +1);
  265		$tagOpen_start = strpos($postTag, '<');
  266		continue;
  267		}
  268
  269		// Do we have a nested tag?
  270		$tagOpen_nested = strpos($fromTagOpen, '<');
  271		$tagOpen_nested_end = strpos(substr($postTag, $tagOpen_end), '>');
  272		if (($tagOpen_nested !== false) && ($tagOpen_nested < $tagOpen_end)) {
  273		$preTag .= substr($postTag, 0, ($tagOpen_nested +1));
  274		$postTag = substr($postTag, ($tagOpen_nested +1));
  275		$tagOpen_start = strpos($postTag, '<');
  276		continue;
  277		}
  278
  279		// Lets get some information about our tag and setup attribute pairs
  280		$tagOpen_nested = (strpos($fromTagOpen, '<') + $tagOpen_start +1);
  281		$currentTag = substr($fromTagOpen, 0, $tagOpen_end);
  282		$tagLength = strlen($currentTag);
  283		$tagLeft = $currentTag;
  284		$attrSet = array ();
  285		$currentSpace = strpos($tagLeft, ' ');
  286
  287		// Are we an open tag or a close tag?
  288		if (substr($currentTag, 0, 1) == '/') {
  289		// Close Tag
  290		$isCloseTag = true;
  291		list ($tagName) = explode(' ', $currentTag);
  292		$tagName = substr($tagName, 1);
  293		} else {
  294		// Open Tag
  295		$isCloseTag = false;
  296		list ($tagName) = explode(' ', $currentTag);
  297		}
  298
  299		/*
  300		* Exclude all "non-regular" tagnames
  301		* OR no tagname
  302		* OR remove if xssauto is on and tag is blacklisted
  303		*/
  304		if ((!preg_match("/^[a-z][a-z0-9]*$/i", $tagName)) || (!$tagName) || ((in_array(strtolower($tagName), $this->tagBlacklist)) && ($this->xssAuto))) {
  305		$postTag = substr($postTag, ($tagLength +2));
  306		$tagOpen_start = strpos($postTag, '<');
  307		// Strip tag
  308		continue;
  309		}
  310
  311		/*
  312		* Time to grab any attributes from the tag... need this section in
  313		* case attributes have spaces in the values.
  314		*/
  315		while ($currentSpace !== false)
  316		{
  317		$fromSpace = substr($tagLeft, ($currentSpace +1));
  318		$nextSpace = strpos($fromSpace, ' ');
  319		$openQuotes = strpos($fromSpace, '"');
  320		$closeQuotes = strpos(substr($fromSpace, ($openQuotes +1)), '"') + $openQuotes +1;
  321
  322		// Do we have an attribute to process? [check for equal sign]
  323		if (strpos($fromSpace, '=') !== false) {
  324		/*
  325		* If the attribute value is wrapped in quotes we need to
  326		* grab the substring from the closing quote, otherwise grab
  327		* till the next space
  328		*/
  329		if (($openQuotes !== false) && (strpos(substr($fromSpace, ($openQuotes +1)), '"') !== false)) {
  330		$attr = substr($fromSpace, 0, ($closeQuotes +1));
  331		} else {
  332		$attr = substr($fromSpace, 0, $nextSpace);
  333		}
  334		} else {
  335		/*
  336		* No more equal signs so add any extra text in the tag into
  337		* the attribute array [eg. checked]
  338		*/
  339		if ($fromSpace != '/') {
  340		$attr = substr($fromSpace, 0, $nextSpace);
  341		}
  342		}
  343
  344		// Last Attribute Pair
  345		if (!$attr && $fromSpace != '/') {
  346		$attr = $fromSpace;
  347		}
  348
  349		// Add attribute pair to the attribute array
  350		$attrSet[] = $attr;
  351
  352		// Move search point and continue iteration
  353		$tagLeft = substr($fromSpace, strlen($attr));
  354		$currentSpace = strpos($tagLeft, ' ');
  355		}
  356
  357		// Is our tag in the user input array?
  358		$tagFound = in_array(strtolower($tagName), $this->tagsArray);
  359
  360		// If the tag is allowed lets append it to the output string
  361		if ((!$tagFound && $this->tagsMethod) || ($tagFound && !$this->tagsMethod)) {
  362
  363		// Reconstruct tag with allowed attributes
  364		if (!$isCloseTag) {
  365		// Open or Single tag
  366		$attrSet = $this->_cleanAttributes($attrSet);
  367		$preTag .= '<'.$tagName;
  368		for ($i = 0; $i < count($attrSet); $i ++)
  369		{
  370		$preTag .= ' '.$attrSet[$i];
  371		}
  372
  373		// Reformat single tags to XHTML
  374		if (strpos($fromTagOpen, '</'.$tagName)) {
  375		$preTag .= '>';
  376		} else {
  377		$preTag .= ' />';
  378		}
  379		} else {
  380		// Closing Tag
  381		$preTag .= '</'.$tagName.'>';
  382		}
  383		}
  384
  385		// Find next tag's start and continue iteration
  386		$postTag = substr($postTag, ($tagLength +2));
  387		$tagOpen_start = strpos($postTag, '<');
  388		}
  389
  390		// Append any code after the end of tags and return
  391		if ($postTag != '<') {
  392		$preTag .= $postTag;
  393		}
  394		return $preTag;
  395		}
  396
  397		/**
  398		* Internal method to strip a tag of certain attributes
  399		*
  400		* @access protected
  401		* @param array $attrSet Array of attribute pairs to filter
  402		* @return array Filtered array of attribute pairs
  403		* @since 1.5
  404		*/
  405		function _cleanAttributes($attrSet)
  406		{
  407		// Initialize variables
  408		$newSet = array();
  409
  410		// Iterate through attribute pairs
  411		for ($i = 0; $i < count($attrSet); $i ++)
  412		{
  413		// Skip blank spaces
  414		if (!$attrSet[$i]) {
  415		continue;
  416		}
  417
  418		// Split into name/value pairs
  419		$attrSubSet = explode('=', trim($attrSet[$i]), 2);
  420		list ($attrSubSet[0]) = explode(' ', $attrSubSet[0]);
  421
  422		/*
  423		* Remove all "non-regular" attribute names
  424		* AND blacklisted attributes
  425		*/
  426		if ((!preg_match('/[a-z]*$/i', $attrSubSet[0])) || (($this->xssAuto) && ((in_array(strtolower($attrSubSet[0]), $this->attrBlacklist)) || (substr($attrSubSet[0], 0, 2) == 'on')))) {
  427		continue;
  428		}
  429
  430		// XSS attribute value filtering
  431		if ($attrSubSet[1]) {
  432		// strips unicode, hex, etc
  433		$attrSubSet[1] = str_replace('&#', '', $attrSubSet[1]);
  434		// strip normal newline within attr value
  435		$attrSubSet[1] = preg_replace('/\s+/', '', $attrSubSet[1]);
  436		// strip double quotes
  437		$attrSubSet[1] = str_replace('"', '', $attrSubSet[1]);
  438		// convert single quotes from either side to doubles (Single quotes shouldn't be used to pad attr value)
  439		if ((substr($attrSubSet[1], 0, 1) == "'") && (substr($attrSubSet[1], (strlen($attrSubSet[1]) - 1), 1) == "'")) {
  440		$attrSubSet[1] = substr($attrSubSet[1], 1, (strlen($attrSubSet[1]) - 2));
  441		}
  442		// strip slashes
  443		$attrSubSet[1] = stripslashes($attrSubSet[1]);
  444		}
  445
  446		// Autostrip script tags
  447		if (JFilterInput::checkAttribute($attrSubSet)) {
  448		continue;
  449		}
  450
  451		// Is our attribute in the user input array?
  452		$attrFound = in_array(strtolower($attrSubSet[0]), $this->attrArray);
  453
  454		// If the tag is allowed lets keep it
  455		if ((!$attrFound && $this->attrMethod) || ($attrFound && !$this->attrMethod)) {
  456
  457		// Does the attribute have a value?
  458		if ($attrSubSet[1]) {
  459		$newSet[] = $attrSubSet[0].'="'.$attrSubSet[1].'"';
  460		} elseif ($attrSubSet[1] == "0") {
  461		/*
  462		* Special Case
  463		* Is the value 0?
  464		*/
  465		$newSet[] = $attrSubSet[0].'="0"';
  466		} else {
  467		$newSet[] = $attrSubSet[0].'="'.$attrSubSet[0].'"';
  468		}
  469		}
  470		}
  471		return $newSet;
  472		}
  473
  474		/**
  475		* Try to convert to plaintext
  476		*
  477		* @access protected
  478		* @param string $source
  479		* @return string Plaintext string
  480		* @since 1.5
  481		*/
  482		function _decode($source)
  483		{
  484		// entity decode
  485		$trans_tbl = get_html_translation_table(HTML_ENTITIES);
  486		foreach($trans_tbl as $k => $v) {
  487		$ttr[$v] = utf8_encode($k);
  488		}
  489		$source = strtr($source, $ttr);
  490		// convert decimal
  491		$source = preg_replace('/&#(\d+);/me', "chr(\\1)", $source); // decimal notation
  492		// convert hex
  493		$source = preg_replace('/&#x([a-f0-9]+);/mei', "chr(0x\\1)", $source); // hex notation
  494		return $source;
  495		}
  	1	<?php
  	2	/**
  	3	* @version $Id$
  	4	* @package Joomla.Framework
  	5	* @subpackage Filter
  	6	* @copyright Copyright (C) 2005 - 2008 Open Source Matters. All rights reserved.
  	7	* @license GNU/GPL, see LICENSE.php
  	8	* Joomla! is free software. This version may have been modified pursuant to the
  	9	* GNU General Public License, and as distributed it includes or is derivative
  	10	* of works licensed under the GNU General Public License or other free or open
  	11	* source software licenses. See COPYRIGHT.php for copyright notices and
  	12	* details.
  	13	*/
  	14
  	15	// Check to ensure this file is within the rest of the framework
  	16	defined('JPATH_BASE') or die();
  	17
  	18	/**
  	19	* JFilterInput is a class for filtering input from any data source
  	20	*
  	21	* Forked from the php input filter library by: Daniel Morris <dan@rootcube.com>
  	22	* Original Contributors: Gianpaolo Racca, Ghislain Picard, Marco Wandschneider, Chris Tobin and Andrew Eddie.
  	23	*
  	24	* @author Louis Landry <louis.landry@joomla.org>
  	25	* @package Joomla.Framework
  	26	* @subpackage Filter
  	27	* @since 1.5
  	28	*/
  	29	class JFilterInput extends JObject
  	30	{
  	31	var $tagsArray; // default = empty array
  	32	var $attrArray; // default = empty array
  	33
  	34	var $tagsMethod; // default = 0
  	35	var $attrMethod; // default = 0
  	36
  	37	var $xssAuto; // default = 1
  	38	var $tagBlacklist = array ('applet', 'body', 'bgsound', 'base', 'basefont', 'embed', 'frame', 'frameset', 'head', 'html', 'id', 'iframe', 'ilayer', 'layer', 'link', 'meta', 'name', 'object', 'script', 'style', 'title', 'xml');
  	39	var $attrBlacklist = array ('action', 'background', 'codebase', 'dynsrc', 'lowsrc'); // also will strip ALL event handlers
  	40
  	41	/**
  	42	* Constructor for inputFilter class. Only first parameter is required.
  	43	*
  	44	* @access protected
  	45	* @param array $tagsArray list of user-defined tags
  	46	* @param array $attrArray list of user-defined attributes
  	47	* @param int $tagsMethod WhiteList method = 0, BlackList method = 1
  	48	* @param int $attrMethod WhiteList method = 0, BlackList method = 1
  	49	* @param int $xssAuto Only auto clean essentials = 0, Allow clean blacklisted tags/attr = 1
  	50	* @since 1.5
  	51	*/
  	52	function __construct($tagsArray = array(), $attrArray = array(), $tagsMethod = 0, $attrMethod = 0, $xssAuto = 1)
  	53	{
  	54	// Make sure user defined arrays are in lowercase
  	55	$tagsArray = array_map('strtolower', (array) $tagsArray);
  	56	$attrArray = array_map('strtolower', (array) $attrArray);
  	57
  	58	// Assign member variables
  	59	$this->tagsArray = $tagsArray;
  	60	$this->attrArray = $attrArray;
  	61	$this->tagsMethod = $tagsMethod;
  	62	$this->attrMethod = $attrMethod;
  	63	$this->xssAuto = $xssAuto;
  	64	}
  	65
  	66	/**
  	67	* Returns a reference to an input filter object, only creating it if it doesn't already exist.
  	68	*
  	69	* This method must be invoked as:
  	70	* <pre> $filter = & JFilterInput::getInstance();</pre>
  	71	*
  	72	* @static
  	73	* @param array $tagsArray list of user-defined tags
  	74	* @param array $attrArray list of user-defined attributes
  	75	* @param int $tagsMethod WhiteList method = 0, BlackList method = 1
  	76	* @param int $attrMethod WhiteList method = 0, BlackList method = 1
  	77	* @param int $xssAuto Only auto clean essentials = 0, Allow clean blacklisted tags/attr = 1
  	78	* @return object The JFilterInput object.
  	79	* @since 1.5
  	80	*/
  	81	function & getInstance($tagsArray = array(), $attrArray = array(), $tagsMethod = 0, $attrMethod = 0, $xssAuto = 1)
  	82	{
  	83	static $instances;
  	84
  	85	$sig = md5(serialize(array($tagsArray,$attrArray,$tagsMethod,$attrMethod,$xssAuto)));
  	86
  	87	if (!isset ($instances)) {
  	88	$instances = array();
  	89	}
  	90
  	91	if (empty ($instances[$sig])) {
  	92	$instances[$sig] = new JFilterInput($tagsArray, $attrArray, $tagsMethod, $attrMethod, $xssAuto);
  	93	}
  	94
  	95	return $instances[$sig];
  	96	}
  	97
  	98	/**
  	99	* Method to be called by another php script. Processes for XSS and
  	100	* specified bad code.
  	101	*
  	102	* @access public
  	103	* @param mixed $source Input string/array-of-string to be 'cleaned'
  	104	* @param string $type Return type for the variable (INT, FLOAT, BOOLEAN, WORD, ALNUM, CMD, BASE64, STRING, ARRAY, PATH, NONE)
  	105	* @return mixed 'Cleaned' version of input parameter
  	106	* @since 1.5
  	107	* @static
  	108	*/
  	109	function clean($source, $type='string')
  	110	{
  	111	// Handle the type constraint
  	112	switch (strtoupper($type))
  	113	{
  	114	case 'INT' :
  	115	case 'INTEGER' :
  	116	// Only use the first integer value
  	117	preg_match('/-?[0-9]+/', (string) $source, $matches);
  	118	$result = @ (int) $matches[0];
  	119	break;
  	120
  	121	case 'FLOAT' :
  	122	case 'DOUBLE' :
  	123	// Only use the first floating point value
  	124	preg_match('/-?[0-9]+(\.[0-9]+)?/', (string) $source, $matches);
  	125	$result = @ (float) $matches[0];
  	126	break;
  	127
  	128	case 'BOOL' :
  	129	case 'BOOLEAN' :
  	130	$result = (bool) $source;
  	131	break;
  	132
  	133	case 'WORD' :
  	134	$result = (string) preg_replace( '/[^A-Z_]/i', '', $source );
  	135	break;
  	136
  	137	case 'ALNUM' :
  	138	$result = (string) preg_replace( '/[^A-Z0-9]/i', '', $source );
  	139	break;
  	140
  	141	case 'CMD' :
  	142	$result = (string) preg_replace( '/[^A-Z0-9_\.-]/i', '', $source );
  	143	$result = ltrim($result, '.');
  	144	break;
  	145
  	146	case 'BASE64' :
  	147	$result = (string) preg_replace( '/[^A-Z0-9\/+=]/i', '', $source );
  	148	break;
  	149
  	150	case 'STRING' :
  	151	// Check for static usage and assign $filter the proper variable
  	152	if(isset($this) && is_a( $this, 'JFilterInput' )) {
  	153	$filter =& $this;
  	154	} else {
  	155	$filter =& JFilterInput::getInstance();
  	156	}
  	157	$result = (string) $filter->_remove($filter->_decode((string) $source));
  	158	break;
  	159
  	160	case 'ARRAY' :
  	161	$result = (array) $source;
  	162	break;
  	163
  	164	case 'PATH' :
  	165	$pattern = '/^[A-Za-z0-9_-]+[A-Za-z0-9_\.-]*([\\\\\/][A-Za-z0-9_-]+[A-Za-z0-9_\.-]*)*$/';
  	166	preg_match($pattern, (string) $source, $matches);
  	167	$result = @ (string) $matches[0];
  	168	break;
  	169
  	170	case 'USERNAME' :
  	171	$result = (string) preg_replace( '/[\x00-\x1F\x7F<>"\'%&]/', '', $source );
  	172	break;
  	173
  	174	default :
  	175	// Check for static usage and assign $filter the proper variable
  	176	if(is_object($this) && get_class($this) == 'JFilterInput') {
  	177	$filter =& $this;
  	178	} else {
  	179	$filter =& JFilterInput::getInstance();
  	180	}
  	181	// Are we dealing with an array?
  	182	if (is_array($source)) {
  	183	foreach ($source as $key => $value)
  	184	{
  	185	// filter element for XSS and other 'bad' code etc.
  	186	if (is_string($value)) {
  	187	$source[$key] = $filter->_remove($filter->_decode($value));
  	188	}
  	189	}
  	190	$result = $source;
  	191	} else {
  	192	// Or a string?
  	193	if (is_string($source) && !empty ($source)) {
  	194	// filter source for XSS and other 'bad' code etc.
  	195	$result = $filter->_remove($filter->_decode($source));
  	196	} else {
  	197	// Not an array or string.. return the passed parameter
  	198	$result = $source;
  	199	}
  	200	}
  	201	break;
  	202	}
  	203	return $result;
  	204	}
  	205
  	206	/**
  	207	* Function to determine if contents of an attribute is safe
  	208	*
  	209	* @static
  	210	* @param array $attrSubSet A 2 element array for attributes name,value
  	211	* @return boolean True if bad code is detected
  	212	* @since 1.5
  	213	*/
  	214	function checkAttribute($attrSubSet)
  	215	{
  	216	$attrSubSet[0] = strtolower($attrSubSet[0]);
  	217	$attrSubSet[1] = strtolower($attrSubSet[1]);
  	218	return (((strpos($attrSubSet[1], 'expression') !== false) && ($attrSubSet[0]) == 'style') || (strpos($attrSubSet[1], 'javascript:') !== false) || (strpos($attrSubSet[1], 'behaviour:') !== false) || (strpos($attrSubSet[1], 'vbscript:') !== false) || (strpos($attrSubSet[1], 'mocha:') !== false) || (strpos($attrSubSet[1], 'livescript:') !== false));
  	219	}
  	220
  	221	/**
  	222	* Internal method to iteratively remove all unwanted tags and attributes
  	223	*
  	224	* @access protected
  	225	* @param string $source Input string to be 'cleaned'
  	226	* @return string 'Cleaned' version of input parameter
  	227	* @since 1.5
  	228	*/
  	229	function _remove($source)
  	230	{
  	231	$loopCounter = 0;
  	232
  	233	// Iteration provides nested tag protection
  	234	while ($source != $this->_cleanTags($source))
  	235	{
  	236	$source = $this->_cleanTags($source);
  	237	$loopCounter ++;
  	238	}
  	239	return $source;
  	240	}
  	241
  	242	/**
  	243	* Internal method to strip a string of certain tags
  	244	*
  	245	* @access protected
  	246	* @param string $source Input string to be 'cleaned'
  	247	* @return string 'Cleaned' version of input parameter
  	248	* @since 1.5
  	249	*/
  	250	function _cleanTags($source)
  	251	{
  	252	/*
  	253	* In the beginning we don't really have a tag, so everything is
  	254	* postTag
  	255	*/
  	256	$preTag = null;
  	257	$postTag = $source;
  	258	$currentSpace = false;
  	259	$attr = ''; // moffats: setting to null due to issues in migration system - undefined variable errors
  	260
  	261	// Is there a tag? If so it will certainly start with a '<'
  	262	$tagOpen_start = strpos($source, '<');
  	263
  	264	while ($tagOpen_start !== false)
  	265	{
  	266	// Get some information about the tag we are processing
  	267	$preTag .= substr($postTag, 0, $tagOpen_start);
  	268	$postTag = substr($postTag, $tagOpen_start);
  	269	$fromTagOpen = substr($postTag, 1);
  	270	$tagOpen_end = strpos($fromTagOpen, '>');
  	271
  	272	// Let's catch any non-terminated tags and skip over them
  	273	if ($tagOpen_end === false) {
  	274	$postTag = substr($postTag, $tagOpen_start +1);
  	275	$tagOpen_start = strpos($postTag, '<');
  	276	continue;
  	277	}
  	278
  	279	// Do we have a nested tag?
  	280	$tagOpen_nested = strpos($fromTagOpen, '<');
  	281	$tagOpen_nested_end = strpos(substr($postTag, $tagOpen_end), '>');
  	282	if (($tagOpen_nested !== false) && ($tagOpen_nested < $tagOpen_end)) {
  	283	$preTag .= substr($postTag, 0, ($tagOpen_nested +1));
  	284	$postTag = substr($postTag, ($tagOpen_nested +1));
  	285	$tagOpen_start = strpos($postTag, '<');
  	286	continue;
  	287	}
  	288
  	289	// Lets get some information about our tag and setup attribute pairs
  	290	$tagOpen_nested = (strpos($fromTagOpen, '<') + $tagOpen_start +1);
  	291	$currentTag = substr($fromTagOpen, 0, $tagOpen_end);
  	292	$tagLength = strlen($currentTag);
  	293	$tagLeft = $currentTag;
  	294	$attrSet = array ();
  	295	$currentSpace = strpos($tagLeft, ' ');
  	296
  	297	// Are we an open tag or a close tag?
  	298	if (substr($currentTag, 0, 1) == '/') {
  	299	// Close Tag
  	300	$isCloseTag = true;
  	301	list ($tagName) = explode(' ', $currentTag);
  	302	$tagName = substr($tagName, 1);
  	303	} else {
  	304	// Open Tag
  	305	$isCloseTag = false;
  	306	list ($tagName) = explode(' ', $currentTag);
  	307	}
  	308
  	309	/*
  	310	* Exclude all "non-regular" tagnames
  	311	* OR no tagname
  	312	* OR remove if xssauto is on and tag is blacklisted
  	313	*/
  	314	if ((!preg_match("/^[a-z][a-z0-9]*$/i", $tagName)) || (!$tagName) || ((in_array(strtolower($tagName), $this->tagBlacklist)) && ($this->xssAuto))) {
  	315	$postTag = substr($postTag, ($tagLength +2));
  	316	$tagOpen_start = strpos($postTag, '<');
  	317	// Strip tag
  	318	continue;
  	319	}
  	320
  	321	/*
  	322	* Time to grab any attributes from the tag... need this section in
  	323	* case attributes have spaces in the values.
  	324	*/
  	325	while ($currentSpace !== false)
  	326	{
  	327	$fromSpace = substr($tagLeft, ($currentSpace +1));
  	328	$nextSpace = strpos($fromSpace, ' ');
  	329	$openQuotes = strpos($fromSpace, '"');
  	330	$closeQuotes = strpos(substr($fromSpace, ($openQuotes +1)), '"') + $openQuotes +1;
  	331
  	332	// Do we have an attribute to process? [check for equal sign]
  	333	if (strpos($fromSpace, '=') !== false) {
  	334	/*
  	335	* If the attribute value is wrapped in quotes we need to
  	336	* grab the substring from the closing quote, otherwise grab
  	337	* till the next space
  	338	*/