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kses.php
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kses.php
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<?php
/**
* HTML/XHTML filter that only allows some elements and attributes
*
* Added wp_ prefix to avoid conflicts with existing kses users
*
* @version 0.2.2
* @copyright (C) 2002, 2003, 2005
* @author Ulf Harnhammar <metaur@users.sourceforge.net>
*
* @package External
* @subpackage KSES
*
* @internal
* *** CONTACT INFORMATION ***
* E-mail: metaur at users dot sourceforge dot net
* Web page: http://sourceforge.net/projects/kses
* Paper mail: Ulf Harnhammar
* Ymergatan 17 C
* 753 25 Uppsala
* SWEDEN
*
* [kses strips evil scripts!]
*/
/**
* You can override this in your my-hacks.php file You can also override this
* in a plugin file. The my-hacks.php is deprecated in its usage.
*
* @since 1.2.0
*/
if (!defined('CUSTOM_TAGS'))
define('CUSTOM_TAGS', false);
if (!CUSTOM_TAGS) {
/**
* Kses global for default allowable HTML tags.
*
* Can be override by using CUSTOM_TAGS constant.
*
* @global array $allowedposttags
* @since 2.0.0
*/
$allowedposttags = array(
'address' => array(),
'a' => array(
'class' => array (),
'href' => array (),
'id' => array (),
'title' => array (),
'rel' => array (),
'rev' => array (),
'name' => array (),
'target' => array()),
'abbr' => array(
'class' => array (),
'title' => array ()),
'acronym' => array(
'title' => array ()),
'b' => array(),
'big' => array(),
'blockquote' => array(
'id' => array (),
'cite' => array (),
'class' => array(),
'lang' => array(),
'xml:lang' => array()),
'br' => array (
'class' => array ()),
'button' => array(
'disabled' => array (),
'name' => array (),
'type' => array (),
'value' => array ()),
'caption' => array(
'align' => array (),
'class' => array ()),
'cite' => array (
'class' => array(),
'dir' => array(),
'lang' => array(),
'title' => array ()),
'code' => array (
'style' => array()),
'col' => array(
'align' => array (),
'char' => array (),
'charoff' => array (),
'span' => array (),
'dir' => array(),
'style' => array (),
'valign' => array (),
'width' => array ()),
'del' => array(
'datetime' => array ()),
'dd' => array(),
'div' => array(
'align' => array (),
'class' => array (),
'dir' => array (),
'lang' => array(),
'style' => array (),
'xml:lang' => array()),
'dl' => array(),
'dt' => array(),
'em' => array(),
'fieldset' => array(),
'font' => array(
'color' => array (),
'face' => array (),
'size' => array ()),
'form' => array(
'action' => array (),
'accept' => array (),
'accept-charset' => array (),
'enctype' => array (),
'method' => array (),
'name' => array (),
'target' => array ()),
'h1' => array(
'align' => array (),
'class' => array (),
'id' => array (),
'style' => array ()),
'h2' => array (
'align' => array (),
'class' => array (),
'id' => array (),
'style' => array ()),
'h3' => array (
'align' => array (),
'class' => array (),
'id' => array (),
'style' => array ()),
'h4' => array (
'align' => array (),
'class' => array (),
'id' => array (),
'style' => array ()),
'h5' => array (
'align' => array (),
'class' => array (),
'id' => array (),
'style' => array ()),
'h6' => array (
'align' => array (),
'class' => array (),
'id' => array (),
'style' => array ()),
'hr' => array (
'align' => array (),
'class' => array (),
'noshade' => array (),
'size' => array (),
'width' => array ()),
'i' => array(),
'img' => array(
'alt' => array (),
'align' => array (),
'border' => array (),
'class' => array (),
'height' => array (),
'hspace' => array (),
'longdesc' => array (),
'vspace' => array (),
'src' => array (),
'style' => array (),
'width' => array ()),
'ins' => array(
'datetime' => array (),
'cite' => array ()),
'kbd' => array(),
'label' => array(
'for' => array ()),
'legend' => array(
'align' => array ()),
'li' => array (
'align' => array (),
'class' => array ()),
'p' => array(
'class' => array (),
'align' => array (),
'dir' => array(),
'lang' => array(),
'style' => array (),
'xml:lang' => array()),
'pre' => array(
'style' => array(),
'width' => array ()),
'q' => array(
'cite' => array ()),
's' => array(),
'span' => array (
'class' => array (),
'dir' => array (),
'align' => array (),
'lang' => array (),
'style' => array (),
'title' => array (),
'xml:lang' => array()),
'strike' => array(),
'strong' => array(),
'sub' => array(),
'sup' => array(),
'table' => array(
'align' => array (),
'bgcolor' => array (),
'border' => array (),
'cellpadding' => array (),
'cellspacing' => array (),
'class' => array (),
'dir' => array(),
'id' => array(),
'rules' => array (),
'style' => array (),
'summary' => array (),
'width' => array ()),
'tbody' => array(
'align' => array (),
'char' => array (),
'charoff' => array (),
'valign' => array ()),
'td' => array(
'abbr' => array (),
'align' => array (),
'axis' => array (),
'bgcolor' => array (),
'char' => array (),
'charoff' => array (),
'class' => array (),
'colspan' => array (),
'dir' => array(),
'headers' => array (),
'height' => array (),
'nowrap' => array (),
'rowspan' => array (),
'scope' => array (),
'style' => array (),
'valign' => array (),
'width' => array ()),
'textarea' => array(
'cols' => array (),
'rows' => array (),
'disabled' => array (),
'name' => array (),
'readonly' => array ()),
'tfoot' => array(
'align' => array (),
'char' => array (),
'class' => array (),
'charoff' => array (),
'valign' => array ()),
'th' => array(
'abbr' => array (),
'align' => array (),
'axis' => array (),
'bgcolor' => array (),
'char' => array (),
'charoff' => array (),
'class' => array (),
'colspan' => array (),
'headers' => array (),
'height' => array (),
'nowrap' => array (),
'rowspan' => array (),
'scope' => array (),
'valign' => array (),
'width' => array ()),
'thead' => array(
'align' => array (),
'char' => array (),
'charoff' => array (),
'class' => array (),
'valign' => array ()),
'title' => array(),
'tr' => array(
'align' => array (),
'bgcolor' => array (),
'char' => array (),
'charoff' => array (),
'class' => array (),
'style' => array (),
'valign' => array ()),
'tt' => array(),
'u' => array(),
'ul' => array (
'class' => array (),
'style' => array (),
'type' => array ()),
'ol' => array (
'class' => array (),
'start' => array (),
'style' => array (),
'type' => array ()),
'var' => array ());
/**
* Kses allowed HTML elements.
*
* @global array $allowedtags
* @since 1.0.0
*/
$allowedtags = array(
'a' => array(
'href' => array (),
'title' => array ()),
'abbr' => array(
'title' => array ()),
'acronym' => array(
'title' => array ()),
'b' => array(),
'blockquote' => array(
'cite' => array ()),
// 'br' => array(),
'cite' => array (),
'code' => array(),
'del' => array(
'datetime' => array ()),
// 'dd' => array(),
// 'dl' => array(),
// 'dt' => array(),
'em' => array (), 'i' => array (),
// 'ins' => array('datetime' => array(), 'cite' => array()),
// 'li' => array(),
// 'ol' => array(),
// 'p' => array(),
'q' => array(
'cite' => array ()),
'strike' => array(),
'strong' => array(),
// 'sub' => array(),
// 'sup' => array(),
// 'u' => array(),
// 'ul' => array(),
);
}
/**
* Filters content and keeps only allowable HTML elements.
*
* This function makes sure that only the allowed HTML element names, attribute
* names and attribute values plus only sane HTML entities will occur in
* $string. You have to remove any slashes from PHP's magic quotes before you
* call this function.
*
* The default allowed protocols are 'http', 'https', 'ftp', 'mailto', 'news',
* 'irc', 'gopher', 'nntp', 'feed', and finally 'telnet. This covers all common
* link protocols, except for 'javascript' which should not be allowed for
* untrusted users.
*
* @since 1.0.0
*
* @param string $string Content to filter through kses
* @param array $allowed_html List of allowed HTML elements
* @param array $allowed_protocols Optional. Allowed protocol in links.
* @return string Filtered content with only allowed HTML elements
*/
function wp_kses($string, $allowed_html, $allowed_protocols = array ('http', 'https', 'ftp', 'ftps', 'mailto', 'news', 'irc', 'gopher', 'nntp', 'feed', 'telnet')) {
$string = wp_kses_no_null($string);
$string = wp_kses_js_entities($string);
$string = wp_kses_normalize_entities($string);
$allowed_html_fixed = wp_kses_array_lc($allowed_html);
$string = wp_kses_hook($string, $allowed_html_fixed, $allowed_protocols); // WP changed the order of these funcs and added args to wp_kses_hook
return wp_kses_split($string, $allowed_html_fixed, $allowed_protocols);
}
/**
* You add any kses hooks here.
*
* There is currently only one kses WordPress hook and it is called here. All
* parameters are passed to the hooks and expected to recieve a string.
*
* @since 1.0.0
*
* @param string $string Content to filter through kses
* @param array $allowed_html List of allowed HTML elements
* @param array $allowed_protocols Allowed protocol in links
* @return string Filtered content through 'pre_kses' hook
*/
function wp_kses_hook($string, $allowed_html, $allowed_protocols) {
$string = apply_filters('pre_kses', $string, $allowed_html, $allowed_protocols);
return $string;
}
/**
* This function returns kses' version number.
*
* @since 1.0.0
*
* @return string KSES Version Number
*/
function wp_kses_version() {
return '0.2.2';
}
/**
* Searches for HTML tags, no matter how malformed.
*
* It also matches stray ">" characters.
*
* @since 1.0.0
*
* @param string $string Content to filter
* @param array $allowed_html Allowed HTML elements
* @param array $allowed_protocols Allowed protocols to keep
* @return string Content with fixed HTML tags
*/
function wp_kses_split($string, $allowed_html, $allowed_protocols) {
global $pass_allowed_html, $pass_allowed_protocols;
$pass_allowed_html = $allowed_html;
$pass_allowed_protocols = $allowed_protocols;
return preg_replace_callback('%((<!--.*?(-->|$))|(<[^>]*(>|$)|>))%',
create_function('$match', 'global $pass_allowed_html, $pass_allowed_protocols; return wp_kses_split2($match[1], $pass_allowed_html, $pass_allowed_protocols);'), $string);
}
/**
* Callback for wp_kses_split for fixing malformed HTML tags.
*
* This function does a lot of work. It rejects some very malformed things like
* <:::>. It returns an empty string, if the element isn't allowed (look ma, no
* strip_tags()!). Otherwise it splits the tag into an element and an attribute
* list.
*
* After the tag is split into an element and an attribute list, it is run
* through another filter which will remove illegal attributes and once that is
* completed, will be returned.
*
* @access private
* @since 1.0.0
* @uses wp_kses_attr()
*
* @param string $string Content to filter
* @param array $allowed_html Allowed HTML elements
* @param array $allowed_protocols Allowed protocols to keep
* @return string Fixed HTML element
*/
function wp_kses_split2($string, $allowed_html, $allowed_protocols) {
$string = wp_kses_stripslashes($string);
if (substr($string, 0, 1) != '<')
return '>';
# It matched a ">" character
if (preg_match('%^<!--(.*?)(-->)?$%', $string, $matches)) {
$string = str_replace(array('<!--', '-->'), '', $matches[1]);
while ( $string != $newstring = wp_kses($string, $allowed_html, $allowed_protocols) )
$string = $newstring;
if ( $string == '' )
return '';
// prevent multiple dashes in comments
$string = preg_replace('/--+/', '-', $string);
// prevent three dashes closing a comment
$string = preg_replace('/-$/', '', $string);
return "<!--{$string}-->";
}
# Allow HTML comments
if (!preg_match('%^<\s*(/\s*)?([a-zA-Z0-9]+)([^>]*)>?$%', $string, $matches))
return '';
# It's seriously malformed
$slash = trim($matches[1]);
$elem = $matches[2];
$attrlist = $matches[3];
if (!@isset($allowed_html[strtolower($elem)]))
return '';
# They are using a not allowed HTML element
if ($slash != '')
return "<$slash$elem>";
# No attributes are allowed for closing elements
return wp_kses_attr("$slash$elem", $attrlist, $allowed_html, $allowed_protocols);
}
/**
* Removes all attributes, if none are allowed for this element.
*
* If some are allowed it calls wp_kses_hair() to split them further, and then
* it builds up new HTML code from the data that kses_hair() returns. It also
* removes "<" and ">" characters, if there are any left. One more thing it does
* is to check if the tag has a closing XHTML slash, and if it does, it puts one
* in the returned code as well.
*
* @since 1.0.0
*
* @param string $element HTML element/tag
* @param string $attr HTML attributes from HTML element to closing HTML element tag
* @param array $allowed_html Allowed HTML elements
* @param array $allowed_protocols Allowed protocols to keep
* @return string Sanitized HTML element
*/
function wp_kses_attr($element, $attr, $allowed_html, $allowed_protocols) {
# Is there a closing XHTML slash at the end of the attributes?
$xhtml_slash = '';
if (preg_match('%\s/\s*$%', $attr))
$xhtml_slash = ' /';
# Are any attributes allowed at all for this element?
if (@ count($allowed_html[strtolower($element)]) == 0)
return "<$element$xhtml_slash>";
# Split it
$attrarr = wp_kses_hair($attr, $allowed_protocols);
# Go through $attrarr, and save the allowed attributes for this element
# in $attr2
$attr2 = '';
foreach ($attrarr as $arreach) {
if (!@ isset ($allowed_html[strtolower($element)][strtolower($arreach['name'])]))
continue; # the attribute is not allowed
$current = $allowed_html[strtolower($element)][strtolower($arreach['name'])];
if ($current == '')
continue; # the attribute is not allowed
if (!is_array($current))
$attr2 .= ' '.$arreach['whole'];
# there are no checks
else {
# there are some checks
$ok = true;
foreach ($current as $currkey => $currval)
if (!wp_kses_check_attr_val($arreach['value'], $arreach['vless'], $currkey, $currval)) {
$ok = false;
break;
}
if ( $arreach['name'] == 'style' ) {
$orig_value = $arreach['value'];
$value = safecss_filter_attr($orig_value);
if ( empty($value) )
continue;
$arreach['value'] = $value;
$arreach['whole'] = str_replace($orig_value, $value, $arreach['whole']);
}
if ($ok)
$attr2 .= ' '.$arreach['whole']; # it passed them
} # if !is_array($current)
} # foreach
# Remove any "<" or ">" characters
$attr2 = preg_replace('/[<>]/', '', $attr2);
return "<$element$attr2$xhtml_slash>";
}
/**
* Builds an attribute list from string containing attributes.
*
* This function does a lot of work. It parses an attribute list into an array
* with attribute data, and tries to do the right thing even if it gets weird
* input. It will add quotes around attribute values that don't have any quotes
* or apostrophes around them, to make it easier to produce HTML code that will
* conform to W3C's HTML specification. It will also remove bad URL protocols
* from attribute values. It also reduces duplicate attributes by using the
* attribute defined first (foo='bar' foo='baz' will result in foo='bar').
*
* @since 1.0.0
*
* @param string $attr Attribute list from HTML element to closing HTML element tag
* @param array $allowed_protocols Allowed protocols to keep
* @return array List of attributes after parsing
*/
function wp_kses_hair($attr, $allowed_protocols) {
$attrarr = array ();
$mode = 0;
$attrname = '';
$uris = array('xmlns', 'profile', 'href', 'src', 'cite', 'classid', 'codebase', 'data', 'usemap', 'longdesc', 'action');
# Loop through the whole attribute list
while (strlen($attr) != 0) {
$working = 0; # Was the last operation successful?
switch ($mode) {
case 0 : # attribute name, href for instance
if (preg_match('/^([-a-zA-Z]+)/', $attr, $match)) {
$attrname = $match[1];
$working = $mode = 1;
$attr = preg_replace('/^[-a-zA-Z]+/', '', $attr);
}
break;
case 1 : # equals sign or valueless ("selected")
if (preg_match('/^\s*=\s*/', $attr)) # equals sign
{
$working = 1;
$mode = 2;
$attr = preg_replace('/^\s*=\s*/', '', $attr);
break;
}
if (preg_match('/^\s+/', $attr)) # valueless
{
$working = 1;
$mode = 0;
if(FALSE === array_key_exists($attrname, $attrarr)) {
$attrarr[$attrname] = array ('name' => $attrname, 'value' => '', 'whole' => $attrname, 'vless' => 'y');
}
$attr = preg_replace('/^\s+/', '', $attr);
}
break;
case 2 : # attribute value, a URL after href= for instance
if (preg_match('/^"([^"]*)"(\s+|$)/', $attr, $match))
# "value"
{
$thisval = $match[1];
if ( in_array($attrname, $uris) )
$thisval = wp_kses_bad_protocol($thisval, $allowed_protocols);
if(FALSE === array_key_exists($attrname, $attrarr)) {
$attrarr[$attrname] = array ('name' => $attrname, 'value' => $thisval, 'whole' => "$attrname=\"$thisval\"", 'vless' => 'n');
}
$working = 1;
$mode = 0;
$attr = preg_replace('/^"[^"]*"(\s+|$)/', '', $attr);
break;
}
if (preg_match("/^'([^']*)'(\s+|$)/", $attr, $match))
# 'value'
{
$thisval = $match[1];
if ( in_array($attrname, $uris) )
$thisval = wp_kses_bad_protocol($thisval, $allowed_protocols);
if(FALSE === array_key_exists($attrname, $attrarr)) {
$attrarr[$attrname] = array ('name' => $attrname, 'value' => $thisval, 'whole' => "$attrname='$thisval'", 'vless' => 'n');
}
$working = 1;
$mode = 0;
$attr = preg_replace("/^'[^']*'(\s+|$)/", '', $attr);
break;
}
if (preg_match("%^([^\s\"']+)(\s+|$)%", $attr, $match))
# value
{
$thisval = $match[1];
if ( in_array($attrname, $uris) )
$thisval = wp_kses_bad_protocol($thisval, $allowed_protocols);
if(FALSE === array_key_exists($attrname, $attrarr)) {
$attrarr[$attrname] = array ('name' => $attrname, 'value' => $thisval, 'whole' => "$attrname=\"$thisval\"", 'vless' => 'n');
}
# We add quotes to conform to W3C's HTML spec.
$working = 1;
$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 && FALSE === array_key_exists($attrname, $attrarr))
# special case, for when the attribute list ends with a valueless
# attribute like "selected"
$attrarr[$attrname] = array ('name' => $attrname, 'value' => '', 'whole' => $attrname, 'vless' => 'y');
return $attrarr;
}
/**
* Performs different checks for attribute values.
*
* The currently implemented checks are "maxlen", "minlen", "maxval", "minval"
* and "valueless" with even more checks to come soon.
*
* @since 1.0.0
*
* @param string $value Attribute value
* @param string $vless Whether the value is valueless or not. Use 'y' or 'n'
* @param string $checkname What $checkvalue is checking for.
* @param mixed $checkvalue What constraint the value should pass
* @return bool Whether check passes (true) or not (false)
*/
function wp_kses_check_attr_val($value, $vless, $checkname, $checkvalue) {
$ok = true;
switch (strtolower($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;
}
/**
* Sanitize string from bad 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)".
*
* @since 1.0.0
*
* @param string $string Content to filter bad protocols from
* @param array $allowed_protocols Allowed protocols to keep
* @return string Filtered content
*/
function wp_kses_bad_protocol($string, $allowed_protocols) {
$string = wp_kses_no_null($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;
}
/**
* Removes any NULL characters in $string.
*
* @since 1.0.0
*
* @param string $string
* @return string
*/
function wp_kses_no_null($string) {
$string = preg_replace('/\0+/', '', $string);
$string = preg_replace('/(\\\\0)+/', '', $string);
return $string;
}
/**
* Strips slashes from in front of quotes.
*
* 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.
*
* @since 1.0.0
*
* @param string $string String to strip slashes
* @return string Fixed strings with quoted slashes
*/
function wp_kses_stripslashes($string) {
return preg_replace('%\\\\"%', '"', $string);
}
/**
* Goes through an array and changes the keys to all lower case.
*
* @since 1.0.0
*
* @param array $inarray Unfiltered array
* @return array Fixed array with all lowercase keys
*/
function wp_kses_array_lc($inarray) {
$outarray = array ();
foreach ( (array) $inarray as $inkey => $inval) {
$outkey = strtolower($inkey);
$outarray[$outkey] = array ();
foreach ( (array) $inval as $inkey2 => $inval2) {
$outkey2 = strtolower($inkey2);
$outarray[$outkey][$outkey2] = $inval2;
} # foreach $inval
} # foreach $inarray
return $outarray;
}
/**
* Removes the HTML JavaScript entities found in early versions of Netscape 4.
*
* @since 1.0.0
*
* @param string $string
* @return string
*/
function wp_kses_js_entities($string) {
return preg_replace('%&\s*\{[^}]*(\}\s*;?|$)%', '', $string);
}
/**
* Handles 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.
*
* @since 1.0.0
*
* @param string $string
* @return string
*/
function wp_kses_html_error($string) {
return preg_replace('/^("[^"]*("|$)|\'[^\']*(\'|$)|\S)*\s*/', '', $string);
}
/**
* Sanitizes content from bad protocols and other characters.
*
* This function searches for URL protocols at the beginning of $string, while
* handling whitespace and HTML entities.
*
* @since 1.0.0
*
* @param string $string Content to check for bad protocols
* @param string $allowed_protocols Allowed protocols
* @return string Sanitized content
*/
function wp_kses_bad_protocol_once($string, $allowed_protocols) {
global $_kses_allowed_protocols;
$_kses_allowed_protocols = $allowed_protocols;
$string2 = preg_split('/:|:|:/i', $string, 2);
if ( isset($string2[1]) && !preg_match('%/\?%', $string2[0]) )
$string = wp_kses_bad_protocol_once2($string2[0]) . trim($string2[1]);
else
$string = preg_replace_callback('/^((&[^;]*;|[\sA-Za-z0-9])*)'.'(:|:|&#[Xx]3[Aa];)\s*/', 'wp_kses_bad_protocol_once2', $string);
return $string;
}
/**
* Callback for wp_kses_bad_protocol_once() regular expression.
*
* 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.
*
* @access private
* @since 1.0.0
*
* @param mixed $matches string or preg_replace_callback() matches array to check for bad protocols
* @return string Sanitized content
*/
function wp_kses_bad_protocol_once2($matches) {
global $_kses_allowed_protocols;
if ( is_array($matches) ) {
if ( ! isset($matches[1]) || empty($matches[1]) )
return '';
$string = $matches[1];
} else {
$string = $matches;
}
$string2 = wp_kses_decode_entities($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 ( (array) $_kses_allowed_protocols as $one_protocol)
if (strtolower($one_protocol) == $string2) {
$allowed = true;
break;
}
if ($allowed)
return "$string2:";
else
return '';
}
/**
* Converts and fixes HTML entities.
*
* This function normalizes HTML entities. It will convert "AT&T" to the correct
* "AT&T", ":" to ":", "&#XYZZY;" to "&#XYZZY;" and so on.
*
* @since 1.0.0
*
* @param string $string Content to normalize entities
* @return string Content with normalized entities
*/
function wp_kses_normalize_entities($string) {
# Disarm all entities by converting & to &
$string = str_replace('&', '&', $string);
# Change back the allowed entities in our entity whitelist
$string = preg_replace('/&([A-Za-z][A-Za-z0-9]{0,19});/', '&\\1;', $string);
$string = preg_replace_callback('/&#0*([0-9]{1,5});/', 'wp_kses_normalize_entities2', $string);
$string = preg_replace_callback('/&#([Xx])0*(([0-9A-Fa-f]{2}){1,2});/', 'wp_kses_normalize_entities3', $string);
return $string;
}
/**
* Callback for wp_kses_normalize_entities() regular expression.
*
* This function helps wp_kses_normalize_entities() to only accept 16 bit values
* and nothing more for &#number; entities.
*
* @access private
* @since 1.0.0
*
* @param array $matches preg_replace_callback() matches array
* @return string Correctly encoded entity
*/
function wp_kses_normalize_entities2($matches) {
if ( ! isset($matches[1]) || empty($matches[1]) )
return '';
$i = $matches[1];
return ( ( ! valid_unicode($i) ) || ($i > 65535) ? "&#$i;" : "&#$i;" );
}
/**
* Callback for wp_kses_normalize_entities() for regular expression.
*
* This function helps wp_kses_normalize_entities() to only accept valid Unicode
* numeric entities in hex form.
*
* @access private
*
* @param array $matches preg_replace_callback() matches array
* @return string Correctly encoded entity
*/
function wp_kses_normalize_entities3($matches) {
if ( ! isset($matches[2]) || empty($matches[2]) )
return '';
$hexchars = $matches[2];