*
* @package External
* @subpackage KSES
*/
/**
* Specifies the default allowable HTML tags.
*
* Using `CUSTOM_TAGS` is not recommended and should be considered deprecated. The
* {@see 'wp_kses_allowed_html'} filter is more powerful and supplies context.
*
* @see wp_kses_allowed_html()
* @since 1.2.0
*
* @var array[]|bool Array of default allowable HTML tags, or false to use the defaults.
*/
if ( ! defined( 'CUSTOM_TAGS' ) ) {
define( 'CUSTOM_TAGS', false );
}
// Ensure that these variables are added to the global namespace
// (e.g. if using namespaces / autoload in the current PHP environment).
global $allowedposttags, $allowedtags, $allowedentitynames;
if ( ! CUSTOM_TAGS ) {
/**
* KSES global for default allowable HTML tags.
*
* Can be overridden with the `CUSTOM_TAGS` constant.
*
* @var array[] $allowedposttags Array of default allowable HTML tags.
* @since 2.0.0
*/
$allowedposttags = array(
'address' => array(),
'a' => array(
'href' => true,
'rel' => true,
'rev' => true,
'name' => true,
'target' => true,
),
'abbr' => array(),
'acronym' => array(),
'area' => array(
'alt' => true,
'coords' => true,
'href' => true,
'nohref' => true,
'shape' => true,
'target' => true,
),
'article' => array(
'align' => true,
'dir' => true,
'lang' => true,
'xml:lang' => true,
),
'aside' => array(
'align' => true,
'dir' => true,
'lang' => true,
'xml:lang' => true,
),
'audio' => array(
'autoplay' => true,
'controls' => true,
'loop' => true,
'muted' => true,
'preload' => true,
'src' => true,
),
'b' => array(),
'bdo' => array(
'dir' => true,
),
'big' => array(),
'blockquote' => array(
'cite' => true,
'lang' => true,
'xml:lang' => true,
),
'br' => array(),
'button' => array(
'disabled' => true,
'name' => true,
'type' => true,
'value' => true,
),
'caption' => array(
'align' => true,
),
'cite' => array(
'dir' => true,
'lang' => true,
),
'code' => array(),
'col' => array(
'align' => true,
'char' => true,
'charoff' => true,
'span' => true,
'dir' => true,
'valign' => true,
'width' => true,
),
'colgroup' => array(
'align' => true,
'char' => true,
'charoff' => true,
'span' => true,
'valign' => true,
'width' => true,
),
'del' => array(
'datetime' => true,
),
'dd' => array(),
'dfn' => array(),
'details' => array(
'align' => true,
'dir' => true,
'lang' => true,
'open' => true,
'xml:lang' => true,
),
'div' => array(
'align' => true,
'dir' => true,
'lang' => true,
'xml:lang' => true,
),
'dl' => array(),
'dt' => array(),
'em' => array(),
'fieldset' => array(),
'figure' => array(
'align' => true,
'dir' => true,
'lang' => true,
'xml:lang' => true,
),
'figcaption' => array(
'align' => true,
'dir' => true,
'lang' => true,
'xml:lang' => true,
),
'font' => array(
'color' => true,
'face' => true,
'size' => true,
),
'footer' => array(
'align' => true,
'dir' => true,
'lang' => true,
'xml:lang' => true,
),
'form' => array(
'action' => true,
'accept' => true,
'accept-charset' => true,
'enctype' => true,
'method' => true,
'name' => true,
'target' => true,
),
'h1' => array(
'align' => true,
),
'h2' => array(
'align' => true,
),
'h3' => array(
'align' => true,
),
'h4' => array(
'align' => true,
),
'h5' => array(
'align' => true,
),
'h6' => array(
'align' => true,
),
'header' => array(
'align' => true,
'dir' => true,
'lang' => true,
'xml:lang' => true,
),
'hgroup' => array(
'align' => true,
'dir' => true,
'lang' => true,
'xml:lang' => true,
),
'hr' => array(
'align' => true,
'noshade' => true,
'size' => true,
'width' => true,
),
'i' => array(),
'img' => array(
'alt' => true,
'align' => true,
'border' => true,
'height' => true,
'hspace' => true,
'longdesc' => true,
'vspace' => true,
'src' => true,
'usemap' => true,
'width' => true,
),
'ins' => array(
'datetime' => true,
'cite' => true,
),
'kbd' => array(),
'label' => array(
'for' => true,
),
'legend' => array(
'align' => true,
),
'li' => array(
'align' => true,
'value' => true,
),
'map' => array(
'name' => true,
),
'mark' => array(),
'menu' => array(
'type' => true,
),
'nav' => array(
'align' => true,
'dir' => true,
'lang' => true,
'xml:lang' => true,
),
'p' => array(
'align' => true,
'dir' => true,
'lang' => true,
'xml:lang' => true,
),
'pre' => array(
'width' => true,
),
'q' => array(
'cite' => true,
),
's' => array(),
'samp' => array(),
'span' => array(
'dir' => true,
'align' => true,
'lang' => true,
'xml:lang' => true,
),
'section' => array(
'align' => true,
'dir' => true,
'lang' => true,
'xml:lang' => true,
),
'small' => array(),
'strike' => array(),
'strong' => array(),
'sub' => array(),
'summary' => array(
'align' => true,
'dir' => true,
'lang' => true,
'xml:lang' => true,
),
'sup' => array(),
'table' => array(
'align' => true,
'bgcolor' => true,
'border' => true,
'cellpadding' => true,
'cellspacing' => true,
'dir' => true,
'rules' => true,
'summary' => true,
'width' => true,
),
'tbody' => array(
'align' => true,
'char' => true,
'charoff' => true,
'valign' => true,
),
'td' => array(
'abbr' => true,
'align' => true,
'axis' => true,
'bgcolor' => true,
'char' => true,
'charoff' => true,
'colspan' => true,
'dir' => true,
'headers' => true,
'height' => true,
'nowrap' => true,
'rowspan' => true,
'scope' => true,
'valign' => true,
'width' => true,
),
'textarea' => array(
'cols' => true,
'rows' => true,
'disabled' => true,
'name' => true,
'readonly' => true,
),
'tfoot' => array(
'align' => true,
'char' => true,
'charoff' => true,
'valign' => true,
),
'th' => array(
'abbr' => true,
'align' => true,
'axis' => true,
'bgcolor' => true,
'char' => true,
'charoff' => true,
'colspan' => true,
'headers' => true,
'height' => true,
'nowrap' => true,
'rowspan' => true,
'scope' => true,
'valign' => true,
'width' => true,
),
'thead' => array(
'align' => true,
'char' => true,
'charoff' => true,
'valign' => true,
),
'title' => array(),
'tr' => array(
'align' => true,
'bgcolor' => true,
'char' => true,
'charoff' => true,
'valign' => true,
),
'track' => array(
'default' => true,
'kind' => true,
'label' => true,
'src' => true,
'srclang' => true,
),
'tt' => array(),
'u' => array(),
'ul' => array(
'type' => true,
),
'ol' => array(
'start' => true,
'type' => true,
'reversed' => true,
),
'var' => array(),
'video' => array(
'autoplay' => true,
'controls' => true,
'height' => true,
'loop' => true,
'muted' => true,
'poster' => true,
'preload' => true,
'src' => true,
'width' => true,
),
);
/**
* @var array[] $allowedtags Array of KSES allowed HTML elements.
* @since 1.0.0
*/
$allowedtags = array(
'a' => array(
'href' => true,
'title' => true,
),
'abbr' => array(
'title' => true,
),
'acronym' => array(
'title' => true,
),
'b' => array(),
'blockquote' => array(
'cite' => true,
),
'cite' => array(),
'code' => array(),
'del' => array(
'datetime' => true,
),
'em' => array(),
'i' => array(),
'q' => array(
'cite' => true,
),
's' => array(),
'strike' => array(),
'strong' => array(),
);
/**
* @var string[] $allowedentitynames Array of KSES allowed HTML entitity names.
* @since 1.0.0
*/
$allowedentitynames = array(
'nbsp',
'iexcl',
'cent',
'pound',
'curren',
'yen',
'brvbar',
'sect',
'uml',
'copy',
'ordf',
'laquo',
'not',
'shy',
'reg',
'macr',
'deg',
'plusmn',
'acute',
'micro',
'para',
'middot',
'cedil',
'ordm',
'raquo',
'iquest',
'Agrave',
'Aacute',
'Acirc',
'Atilde',
'Auml',
'Aring',
'AElig',
'Ccedil',
'Egrave',
'Eacute',
'Ecirc',
'Euml',
'Igrave',
'Iacute',
'Icirc',
'Iuml',
'ETH',
'Ntilde',
'Ograve',
'Oacute',
'Ocirc',
'Otilde',
'Ouml',
'times',
'Oslash',
'Ugrave',
'Uacute',
'Ucirc',
'Uuml',
'Yacute',
'THORN',
'szlig',
'agrave',
'aacute',
'acirc',
'atilde',
'auml',
'aring',
'aelig',
'ccedil',
'egrave',
'eacute',
'ecirc',
'euml',
'igrave',
'iacute',
'icirc',
'iuml',
'eth',
'ntilde',
'ograve',
'oacute',
'ocirc',
'otilde',
'ouml',
'divide',
'oslash',
'ugrave',
'uacute',
'ucirc',
'uuml',
'yacute',
'thorn',
'yuml',
'quot',
'amp',
'lt',
'gt',
'apos',
'OElig',
'oelig',
'Scaron',
'scaron',
'Yuml',
'circ',
'tilde',
'ensp',
'emsp',
'thinsp',
'zwnj',
'zwj',
'lrm',
'rlm',
'ndash',
'mdash',
'lsquo',
'rsquo',
'sbquo',
'ldquo',
'rdquo',
'bdquo',
'dagger',
'Dagger',
'permil',
'lsaquo',
'rsaquo',
'euro',
'fnof',
'Alpha',
'Beta',
'Gamma',
'Delta',
'Epsilon',
'Zeta',
'Eta',
'Theta',
'Iota',
'Kappa',
'Lambda',
'Mu',
'Nu',
'Xi',
'Omicron',
'Pi',
'Rho',
'Sigma',
'Tau',
'Upsilon',
'Phi',
'Chi',
'Psi',
'Omega',
'alpha',
'beta',
'gamma',
'delta',
'epsilon',
'zeta',
'eta',
'theta',
'iota',
'kappa',
'lambda',
'mu',
'nu',
'xi',
'omicron',
'pi',
'rho',
'sigmaf',
'sigma',
'tau',
'upsilon',
'phi',
'chi',
'psi',
'omega',
'thetasym',
'upsih',
'piv',
'bull',
'hellip',
'prime',
'Prime',
'oline',
'frasl',
'weierp',
'image',
'real',
'trade',
'alefsym',
'larr',
'uarr',
'rarr',
'darr',
'harr',
'crarr',
'lArr',
'uArr',
'rArr',
'dArr',
'hArr',
'forall',
'part',
'exist',
'empty',
'nabla',
'isin',
'notin',
'ni',
'prod',
'sum',
'minus',
'lowast',
'radic',
'prop',
'infin',
'ang',
'and',
'or',
'cap',
'cup',
'int',
'sim',
'cong',
'asymp',
'ne',
'equiv',
'le',
'ge',
'sub',
'sup',
'nsub',
'sube',
'supe',
'oplus',
'otimes',
'perp',
'sdot',
'lceil',
'rceil',
'lfloor',
'rfloor',
'lang',
'rang',
'loz',
'spades',
'clubs',
'hearts',
'diams',
'sup1',
'sup2',
'sup3',
'frac14',
'frac12',
'frac34',
'there4',
);
$allowedposttags = array_map( '_wp_add_global_attributes', $allowedposttags );
} else {
$allowedtags = wp_kses_array_lc( $allowedtags );
$allowedposttags = wp_kses_array_lc( $allowedposttags );
}
/**
* Filters text content and strips out disallowed HTML.
*
* This function makes sure that only the allowed HTML element names, attribute
* names, attribute values, and HTML entities will occur in the given text string.
*
* This function expects unslashed data.
*
* @see wp_kses_post() for specifically filtering post content and fields.
* @see wp_allowed_protocols() for the default allowed protocols in link URLs.
*
* @since 1.0.0
*
* @param string $string Text content to filter.
* @param array[]|string $allowed_html An array of allowed HTML elements and attributes, or a
* context name such as 'post'.
* @param string[] $allowed_protocols Array of allowed URL protocols.
* @return string Filtered content containing only the allowed HTML.
*/
function wp_kses( $string, $allowed_html, $allowed_protocols = array() ) {
if ( empty( $allowed_protocols ) ) {
$allowed_protocols = wp_allowed_protocols();
}
$string = wp_kses_no_null( $string, array( 'slash_zero' => 'keep' ) );
$string = wp_kses_normalize_entities( $string );
$string = wp_kses_hook( $string, $allowed_html, $allowed_protocols );
return wp_kses_split( $string, $allowed_html, $allowed_protocols );
}
/**
* Filters one HTML attribute and ensures its value is allowed.
*
* This function can escape data in some situations where `wp_kses()` must strip the whole attribute.
*
* @since 4.2.3
*
* @param string $string The 'whole' attribute, including name and value.
* @param string $element The HTML element name to which the attribute belongs.
* @return string Filtered attribute.
*/
function wp_kses_one_attr( $string, $element ) {
$uris = array( 'xmlns', 'profile', 'href', 'src', 'cite', 'classid', 'codebase', 'data', 'usemap', 'longdesc', 'action' );
$allowed_html = wp_kses_allowed_html( 'post' );
$allowed_protocols = wp_allowed_protocols();
$string = wp_kses_no_null( $string, array( 'slash_zero' => 'keep' ) );
// Preserve leading and trailing whitespace.
$matches = array();
preg_match( '/^\s*/', $string, $matches );
$lead = $matches[0];
preg_match( '/\s*$/', $string, $matches );
$trail = $matches[0];
if ( empty( $trail ) ) {
$string = substr( $string, strlen( $lead ) );
} else {
$string = substr( $string, strlen( $lead ), -strlen( $trail ) );
}
// Parse attribute name and value from input.
$split = preg_split( '/\s*=\s*/', $string, 2 );
$name = $split[0];
if ( count( $split ) == 2 ) {
$value = $split[1];
// Remove quotes surrounding $value.
// Also guarantee correct quoting in $string for this one attribute.
if ( '' == $value ) {
$quote = '';
} else {
$quote = $value[0];
}
if ( '"' == $quote || "'" == $quote ) {
if ( substr( $value, -1 ) != $quote ) {
return '';
}
$value = substr( $value, 1, -1 );
} else {
$quote = '"';
}
// Sanitize quotes, angle braces, and entities.
$value = esc_attr( $value );
// Sanitize URI values.
if ( in_array( strtolower( $name ), $uris ) ) {
$value = wp_kses_bad_protocol( $value, $allowed_protocols );
}
$string = "$name=$quote$value$quote";
$vless = 'n';
} else {
$value = '';
$vless = 'y';
}
// Sanitize attribute by name.
wp_kses_attr_check( $name, $value, $string, $vless, $element, $allowed_html );
// Restore whitespace.
return $lead . $string . $trail;
}
/**
* Returns an array of allowed HTML tags and attributes for a given context.
*
* @since 3.5.0
*
* @global array $allowedposttags
* @global array $allowedtags
* @global array $allowedentitynames
*
* @param string|array $context The context for which to retrieve tags. Allowed values are 'post',
* 'strip', 'data', 'entities', or the name of a field filter such as
* 'pre_user_description'.
* @return array Array of allowed HTML tags and their allowed attributes.
*/
function wp_kses_allowed_html( $context = '' ) {
global $allowedposttags, $allowedtags, $allowedentitynames;
if ( is_array( $context ) ) {
/**
* Filters the HTML that is allowed for a given context.
*
* @since 3.5.0
*
* @param array[]|string $context Context to judge allowed tags by.
* @param string $context_type Context name.
*/
return apply_filters( 'wp_kses_allowed_html', $context, 'explicit' );
}
switch ( $context ) {
case 'post':
/** This filter is documented in wp-includes/kses.php */
return apply_filters( 'wp_kses_allowed_html', $allowedposttags, $context );
case 'user_description':
case 'pre_user_description':
$tags = $allowedtags;
$tags['a']['rel'] = true;
/** This filter is documented in wp-includes/kses.php */
return apply_filters( 'wp_kses_allowed_html', $tags, $context );
case 'strip':
/** This filter is documented in wp-includes/kses.php */
return apply_filters( 'wp_kses_allowed_html', array(), $context );
case 'entities':
/** This filter is documented in wp-includes/kses.php */
return apply_filters( 'wp_kses_allowed_html', $allowedentitynames, $context );
case 'data':
default:
/** This filter is documented in wp-includes/kses.php */
return apply_filters( 'wp_kses_allowed_html', $allowedtags, $context );
}
}
/**
* You add any KSES hooks here.
*
* There is currently only one KSES WordPress hook, {@see 'pre_kses'}, and it is called here.
* All parameters are passed to the hooks and expected to receive a string.
*
* @since 1.0.0
*
* @param string $string Content to filter through KSES.
* @param array[]|string $allowed_html List of allowed HTML elements.
* @param string[] $allowed_protocols Array of allowed URL protocols.
* @return string Filtered content through {@see 'pre_kses'} hook.
*/
function wp_kses_hook( $string, $allowed_html, $allowed_protocols ) {
/**
* Filters content to be run through kses.
*
* @since 2.3.0
*
* @param string $string Content to run through KSES.
* @param array[]|string $allowed_html Allowed HTML elements.
* @param string[] $allowed_protocols Array of allowed URL protocols.
*/
return apply_filters( 'pre_kses', $string, $allowed_html, $allowed_protocols );
}
/**
* Returns the version number of KSES.
*
* @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
*
* @global array $pass_allowed_html
* @global array $pass_allowed_protocols
*
* @param string $string Content to filter.
* @param array $allowed_html Allowed HTML elements.
* @param string[] $allowed_protocols Array of allowed URL protocols.
* @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 = $allowed_protocols;
return preg_replace_callback( '%(|$))|(<[^>]*(>|$)|>)%', '_wp_kses_split_callback', $string );
}
/**
* Callback for `wp_kses_split()`.
*
* @since 3.1.0
* @access private
* @ignore
*
* @global array $pass_allowed_html
* @global array $pass_allowed_protocols
*
* @return string
*/
function _wp_kses_split_callback( $match ) {
global $pass_allowed_html, $pass_allowed_protocols;
return wp_kses_split2( $match[0], $pass_allowed_html, $pass_allowed_protocols );
}
/**
* 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
* @ignore
* @since 1.0.0
*
* @param string $string Content to filter.
* @param array $allowed_html Allowed HTML elements.
* @param string[] $allowed_protocols Array of allowed URL protocols.
* @return string Fixed HTML element
*/
function wp_kses_split2( $string, $allowed_html, $allowed_protocols ) {
$string = wp_kses_stripslashes( $string );
// It matched a ">" character.
if ( substr( $string, 0, 1 ) != '<' ) {
return '>';
}
// Allow HTML comments.
if ( '' ), '', $string );
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
$string = preg_replace( '/-$/', '', $string );
return "";
}
// It's seriously malformed.
if ( ! preg_match( '%^<\s*(/\s*)?([a-zA-Z0-9-]+)([^>]*)>?$%', $string, $matches ) ) {
return '';
}
$slash = trim( $matches[1] );
$elem = $matches[2];
$attrlist = $matches[3];
if ( ! is_array( $allowed_html ) ) {
$allowed_html = wp_kses_allowed_html( $allowed_html );
}
// They are using a not allowed HTML element.
if ( ! isset( $allowed_html[ strtolower( $elem ) ] ) ) {
return '';
}
// No attributes are allowed for closing elements.
if ( $slash != '' ) {
return "$elem>";
}
return wp_kses_attr( $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 string[] $allowed_protocols Array of allowed URL protocols.
* @return string Sanitized HTML element.
*/
function wp_kses_attr( $element, $attr, $allowed_html, $allowed_protocols ) {
if ( ! is_array( $allowed_html ) ) {
$allowed_html = wp_kses_allowed_html( $allowed_html );
}
// 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?
$element_low = strtolower( $element );
if ( empty( $allowed_html[ $element_low ] ) || true === $allowed_html[ $element_low ] ) {
return "<$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 ( wp_kses_attr_check( $arreach['name'], $arreach['value'], $arreach['whole'], $arreach['vless'], $element, $allowed_html ) ) {
$attr2 .= ' ' . $arreach['whole'];
}
}
// Remove any "<" or ">" characters
$attr2 = preg_replace( '/[<>]/', '', $attr2 );
return "<$element$attr2$xhtml_slash>";
}
/**
* Determines whether an attribute is allowed.
*
* @since 4.2.3
*
* @param string $name The attribute name. Passed by reference. Returns empty string when not allowed.
* @param string $value The attribute value. Passed by reference. Returns a filtered value.
* @param string $whole The `name=value` input. Passed by reference. Returns filtered input.
* @param string $vless Whether the attribute is valueless. Use 'y' or 'n'.
* @param string $element The name of the element to which this attribute belongs.
* @param array $allowed_html The full list of allowed elements and attributes.
* @return bool Whether or not the attribute is allowed.
*/
function wp_kses_attr_check( &$name, &$value, &$whole, $vless, $element, $allowed_html ) {
$allowed_attr = $allowed_html[ strtolower( $element ) ];
$name_low = strtolower( $name );
if ( ! isset( $allowed_attr[ $name_low ] ) || '' == $allowed_attr[ $name_low ] ) {
$name = $value = $whole = '';
return false;
}
if ( 'style' == $name_low ) {
$new_value = safecss_filter_attr( $value );
if ( empty( $new_value ) ) {
$name = $value = $whole = '';
return false;
}
$whole = str_replace( $value, $new_value, $whole );
$value = $new_value;
}
if ( is_array( $allowed_attr[ $name_low ] ) ) {
// there are some checks
foreach ( $allowed_attr[ $name_low ] as $currkey => $currval ) {
if ( ! wp_kses_check_attr_val( $value, $vless, $currkey, $currval ) ) {
$name = $value = $whole = '';
return false;
}
}
}
return true;
}
/**
* 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 string[] $allowed_protocols Array of allowed URL protocols.
* @return array[] Array of attribute information 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:
if ( preg_match( '/^([-a-zA-Z:]+)/', $attr, $match ) ) {
$attrname = $match[1];
$working = $mode = 1;
$attr = preg_replace( '/^[-a-zA-Z:]+/', '', $attr );
}
break;
case 1:
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+/', '', $attr );
}
break;
case 2:
if ( preg_match( '%^"([^"]*)"(\s+|/?$)%', $attr, $match ) ) {
// "value"
$thisval = $match[1];
if ( in_array( strtolower( $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( strtolower( $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( strtolower( $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;
}
/**
* Finds all attributes of an HTML element.
*
* Does not modify input. May return "evil" output.
*
* Based on `wp_kses_split2()` and `wp_kses_attr()`.
*
* @since 4.2.3
*
* @param string $element HTML element.
* @return array|bool List of attributes found in the element. Returns false on failure.
*/
function wp_kses_attr_parse( $element ) {
$valid = preg_match( '%^(<\s*)(/\s*)?([a-zA-Z0-9]+\s*)([^>]*)(>?)$%', $element, $matches );
if ( 1 !== $valid ) {
return false;
}
$begin = $matches[1];
$slash = $matches[2];
$elname = $matches[3];
$attr = $matches[4];
$end = $matches[5];
if ( '' !== $slash ) {
// Closing elements do not get parsed.
return false;
}
// Is there a closing XHTML slash at the end of the attributes?
if ( 1 === preg_match( '%\s*/\s*$%', $attr, $matches ) ) {
$xhtml_slash = $matches[0];
$attr = substr( $attr, 0, -strlen( $xhtml_slash ) );
} else {
$xhtml_slash = '';
}
// Split it
$attrarr = wp_kses_hair_parse( $attr );
if ( false === $attrarr ) {
return false;
}
// Make sure all input is returned by adding front and back matter.
array_unshift( $attrarr, $begin . $slash . $elname );
array_push( $attrarr, $xhtml_slash . $end );
return $attrarr;
}
/**
* Builds an attribute list from string containing attributes.
*
* Does not modify input. May return "evil" output.
* In case of unexpected input, returns false instead of stripping things.
*
* Based on `wp_kses_hair()` but does not return a multi-dimensional array.
*
* @since 4.2.3
*
* @param string $attr Attribute list from HTML element to closing HTML element tag.
* @return array|bool List of attributes found in $attr. Returns false on failure.
*/
function wp_kses_hair_parse( $attr ) {
if ( '' === $attr ) {
return array();
}
// phpcs:disable Squiz.Strings.ConcatenationSpacing.PaddingFound -- don't remove regex indentation
$regex =
'(?:'
. '[-a-zA-Z:]+' // Attribute name.
. '|'
. '\[\[?[^\[\]]+\]\]?' // Shortcode in the name position implies unfiltered_html.
. ')'
. '(?:' // Attribute value.
. '\s*=\s*' // All values begin with '='
. '(?:'
. '"[^"]*"' // Double-quoted
. '|'
. "'[^']*'" // Single-quoted
. '|'
. '[^\s"\']+' // Non-quoted
. '(?:\s|$)' // Must have a space
. ')'
. '|'
. '(?:\s|$)' // If attribute has no value, space is required.
. ')'
. '\s*'; // Trailing space is optional except as mentioned above.
// phpcs:enable
// Although it is possible to reduce this procedure to a single regexp,
// we must run that regexp twice to get exactly the expected result.
$validation = "%^($regex)+$%";
$extraction = "%$regex%";
if ( 1 === preg_match( $validation, $attr ) ) {
preg_match_all( $extraction, $attr, $attrarr );
return $attrarr[0];
} else {
return false;
}
}
/**
* Performs different checks for attribute values.
*
* The currently implemented checks are "maxlen", "minlen", "maxval", "minval",
* and "valueless".
*
* @since 1.0.0
*
* @param string $value Attribute value.
* @param string $vless Whether the attribute is valueless. 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.
*/
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 ) {
$ok = false;
}
break;
case 'minval':
// The minval check makes sure that the attribute value is a positive integer,
// and that it is not smaller than the given value.
if ( ! preg_match( '/^\s{0,6}[0-9]{1,6}\s{0,6}$/', $value ) ) {
$ok = false;
}
if ( $value < $checkvalue ) {
$ok = false;
}
break;
case 'valueless':
// The valueless check makes sure if the attribute has a value
// (like ``) or not (`