kses.php

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					$mode = 0;
					$attr = preg_replace("%^[^\s\"']+(\s+|$)%", '', $attr);
				}

				break;
		} # switch

		if ($working == 0) # not well formed, remove and try again
			{
			$attr = wp_kses_html_error($attr);
			$mode = 0;
		}
	} # while

	if ($mode == 1)
		# special case, for when the attribute list ends with a valueless
		# attribute like "selected"
		$attrarr[] = array ('name' => $attrname, 'value' => '', 'whole' => $attrname, 'vless' => 'y');

	return $attrarr;
} # function wp_kses_hair

function wp_kses_check_attr_val($value, $vless, $checkname, $checkvalue)
###############################################################################
# This function performs different checks for attribute values. The currently
# implemented checks are "maxlen", "minlen", "maxval", "minval" and "valueless"
# with even more checks to come soon.
###############################################################################
{
	$ok = true;

	switch (strtolower($checkname)) {
		case 'maxlen' :
			# The maxlen check makes sure that the attribute value has a length not
			# greater than the given value. This can be used to avoid Buffer Overflows
			# in WWW clients and various Internet servers.

			if (strlen($value) > $checkvalue)
				$ok = false;
			break;

		case 'minlen' :
			# The minlen check makes sure that the attribute value has a length not
			# smaller than the given value.

			if (strlen($value) < $checkvalue)
				$ok = false;
			break;

		case 'maxval' :
			# The maxval check does two things: it checks that the attribute value is
			# an integer from 0 and up, without an excessive amount of zeroes or
			# whitespace (to avoid Buffer Overflows). It also checks that the attribute
			# value is not greater than the given value.
			# This check can be used to avoid Denial of Service attacks.

			if (!preg_match('/^\s{0,6}[0-9]{1,6}\s{0,6}$/', $value))
				$ok = false;
			if ($value > $checkvalue)
				$ok = false;
			break;

		case 'minval' :
			# The minval check checks that the attribute value is a positive integer,
			# and that it is not smaller than the given value.

			if (!preg_match('/^\s{0,6}[0-9]{1,6}\s{0,6}$/', $value))
				$ok = false;
			if ($value < $checkvalue)
				$ok = false;
			break;

		case 'valueless' :
			# The valueless check checks if the attribute has a value
			# (like <a href="blah">) or not (<option selected>). If the given value
			# is a "y" or a "Y", the attribute must not have a value.
			# If the given value is an "n" or an "N", the attribute must have one.

			if (strtolower($checkvalue) != $vless)
				$ok = false;
			break;
	} # switch

	return $ok;
} # function wp_kses_check_attr_val

function wp_kses_bad_protocol($string, $allowed_protocols)
###############################################################################
# This function removes all non-allowed protocols from the beginning of
# $string. It ignores whitespace and the case of the letters, and it does
# understand HTML entities. It does its work in a while loop, so it won't be
# fooled by a string like "javascript:javascript:alert(57)".
###############################################################################
{
	$string = wp_kses_no_null($string);
	$string = preg_replace('/\xad+/', '', $string); # deals with Opera "feature"
	$string2 = $string.'a';

	while ($string != $string2) {
		$string2 = $string;
		$string = wp_kses_bad_protocol_once($string, $allowed_protocols);
	} # while

	return $string;
} # function wp_kses_bad_protocol

function wp_kses_no_null($string)
###############################################################################
# This function removes any NULL characters in $string.
###############################################################################
{
	$string = preg_replace('/\0+/', '', $string);
	$string = preg_replace('/(\\\\0)+/', '', $string);

	return $string;
} # function wp_kses_no_null

function wp_kses_stripslashes($string)
###############################################################################
# This function changes the character sequence  \"  to just  "
# It leaves all other slashes alone. It's really weird, but the quoting from
# preg_replace(//e) seems to require this.
###############################################################################
{
	return preg_replace('%\\\\"%', '"', $string);
} # function wp_kses_stripslashes

function wp_kses_array_lc($inarray)
###############################################################################
# This function goes through an array, and changes the keys to all lower case.
###############################################################################
{
	$outarray = array ();

	foreach ($inarray as $inkey => $inval) {
		$outkey = strtolower($inkey);
		$outarray[$outkey] = array ();

		foreach ($inval as $inkey2 => $inval2) {
			$outkey2 = strtolower($inkey2);
			$outarray[$outkey][$outkey2] = $inval2;
		} # foreach $inval
	} # foreach $inarray

	return $outarray;
} # function wp_kses_array_lc

function wp_kses_js_entities($string)
###############################################################################
# This function removes the HTML JavaScript entities found in early versions of
# Netscape 4.
###############################################################################
{
	return preg_replace('%&\s*\{[^}]*(\}\s*;?|$)%', '', $string);
} # function wp_kses_js_entities

function wp_kses_html_error($string)
###############################################################################
# This function deals with parsing errors in wp_kses_hair(). The general plan is
# to remove everything to and including some whitespace, but it deals with
# quotes and apostrophes as well.
###############################################################################
{
	return preg_replace('/^("[^"]*("|$)|\'[^\']*(\'|$)|\S)*\s*/', '', $string);
} # function wp_kses_html_error

function wp_kses_bad_protocol_once($string, $allowed_protocols)
###############################################################################
# This function searches for URL protocols at the beginning of $string, while
# handling whitespace and HTML entities.
###############################################################################
{
	return preg_replace('/^((&[^;]*;|[\sA-Za-z0-9])*)'.'(:|&#58;|&#[Xx]3[Aa];)\s*/e', 'wp_kses_bad_protocol_once2("\\1", $allowed_protocols)', $string);
} # function wp_kses_bad_protocol_once

function wp_kses_bad_protocol_once2($string, $allowed_protocols)
###############################################################################
# This function processes URL protocols, checks to see if they're in the white-
# list or not, and returns different data depending on the answer.
###############################################################################
{
	$string2 = wp_kses_decode_entities($string);
	$string2 = preg_replace('/\s/', '', $string2);
	$string2 = wp_kses_no_null($string2);
	$string2 = preg_replace('/\xad+/', '', $string2);
	# deals with Opera "feature"
	$string2 = strtolower($string2);

	$allowed = false;
	foreach ($allowed_protocols as $one_protocol)
		if (strtolower($one_protocol) == $string2) {
			$allowed = true;
			break;
		}

	if ($allowed)
		return "$string2:";
	else
		return '';
} # function wp_kses_bad_protocol_once2

function wp_kses_normalize_entities($string)
###############################################################################
# This function normalizes HTML entities. It will convert "AT&T" to the correct
# "AT&amp;T", "&#00058;" to "&#58;", "&#XYZZY;" to "&amp;#XYZZY;" and so on.
###############################################################################
{
	# Disarm all entities by converting & to &amp;

	$string = str_replace('&', '&amp;', $string);

	# Change back the allowed entities in our entity whitelist

	$string = preg_replace('/&amp;([A-Za-z][A-Za-z0-9]{0,19});/', '&\\1;', $string);
	$string = preg_replace('/&amp;#0*([0-9]{1,5});/e', 'wp_kses_normalize_entities2("\\1")', $string);
	$string = preg_replace('/&amp;#([Xx])0*(([0-9A-Fa-f]{2}){1,2});/', '&#\\1\\2;', $string);

	return $string;
} # function wp_kses_normalize_entities

function wp_kses_normalize_entities2($i)
###############################################################################
# This function helps wp_kses_normalize_entities() to only accept 16 bit values
# and nothing more for &#number; entities.
###############################################################################
{
	return (($i > 65535) ? "&amp;#$i;" : "&#$i;");
} # function wp_kses_normalize_entities2

function wp_kses_decode_entities($string)
###############################################################################
# This function decodes numeric HTML entities (&#65; and &#x41;). It doesn't
# do anything with other entities like &auml;, but we don't need them in the
# URL protocol whitelisting system anyway.
###############################################################################
{
	$string = preg_replace('/&#([0-9]+);/e', 'chr("\\1")', $string);
	$string = preg_replace('/&#[Xx]([0-9A-Fa-f]+);/e', 'chr(hexdec("\\1"))', $string);

	return $string;
} # function wp_kses_decode_entities

function wp_filter_kses($data) {
	global $allowedtags;
	return wp_kses($data, $allowedtags);
}

function wp_filter_post_kses($data) {
	global $allowedposttags;
	return addslashes ( wp_kses(stripslashes( $data ), $allowedposttags) );
}

function kses_init_filters() {
		add_filter('pre_comment_author', 'wp_filter_kses');
		add_filter('pre_comment_content', 'wp_filter_kses');
		add_filter('content_save_pre', 'wp_filter_post_kses');
		add_filter('title_save_pre', 'wp_filter_kses');
}

function kses_init() {
	remove_filter('pre_comment_author', 'wp_filter_kses');
	remove_filter('pre_comment_content', 'wp_filter_kses');
	remove_filter('content_save_pre', 'wp_filter_post_kses');
	remove_filter('title_save_pre', 'wp_filter_kses');

	if (current_user_can('unfiltered_html') == false)
		kses_init_filters();
}
add_action('init', 'kses_init');
add_action('set_current_user', 'kses_init');
?>