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mirror of https://github.com/ezyang/htmlpurifier.git synced 2025-08-06 06:07:26 +02:00

[1.5.0] AttrDef partitioned into HTML, CSS and URI segments. Also, some minor bugs with MultiLength fixed.

git-svn-id: http://htmlpurifier.org/svnroot/htmlpurifier/trunk@747 48356398-32a2-884e-a903-53898d9a118a
This commit is contained in:
Edward Z. Yang
2007-02-14 20:38:51 +00:00
parent 93a69d020a
commit c05eebee15
55 changed files with 301 additions and 298 deletions

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<?php
require_once 'HTMLPurifier/AttrDef.php';
require_once 'HTMLPurifier/CSSDefinition.php';
/**
* Validates shorthand CSS property background.
* @warning Does not support url tokens that have internal spaces.
*/
class HTMLPurifier_AttrDef_CSS_Background extends HTMLPurifier_AttrDef
{
/**
* Local copy of component validators.
* @note See HTMLPurifier_AttrDef_Font::$info for a similar impl.
*/
var $info;
function HTMLPurifier_AttrDef_CSS_Background($config) {
$def = $config->getCSSDefinition();
$this->info['background-color'] = $def->info['background-color'];
$this->info['background-image'] = $def->info['background-image'];
$this->info['background-repeat'] = $def->info['background-repeat'];
$this->info['background-attachment'] = $def->info['background-attachment'];
$this->info['background-position'] = $def->info['background-position'];
}
function validate($string, $config, &$context) {
// regular pre-processing
$string = $this->parseCDATA($string);
if ($string === '') return false;
// assumes URI doesn't have spaces in it
$bits = explode(' ', strtolower($string)); // bits to process
$caught = array();
$caught['color'] = false;
$caught['image'] = false;
$caught['repeat'] = false;
$caught['attachment'] = false;
$caught['position'] = false;
$i = 0; // number of catches
$none = false;
foreach ($bits as $bit) {
if ($bit === '') continue;
foreach ($caught as $key => $status) {
if ($key != 'position') {
if ($status !== false) continue;
$r = $this->info['background-' . $key]->validate($bit, $config, $context);
} else {
$r = $bit;
}
if ($r === false) continue;
if ($key == 'position') {
if ($caught[$key] === false) $caught[$key] = '';
$caught[$key] .= $r . ' ';
} else {
$caught[$key] = $r;
}
$i++;
break;
}
}
if (!$i) return false;
if ($caught['position'] !== false) {
$caught['position'] = $this->info['background-position']->
validate($caught['position'], $config, $context);
}
$ret = array();
foreach ($caught as $value) {
if ($value === false) continue;
$ret[] = $value;
}
if (empty($ret)) return false;
return implode(' ', $ret);
}
}
?>

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<?php
require_once 'HTMLPurifier/AttrDef.php';
require_once 'HTMLPurifier/AttrDef/CSS/Length.php';
require_once 'HTMLPurifier/AttrDef/CSS/Percentage.php';
/* W3C says:
[ // adjective and number must be in correct order, even if
// you could switch them without introducing ambiguity.
// some browsers support that syntax
[
<percentage> | <length> | left | center | right
]
[
<percentage> | <length> | top | center | bottom
]?
] |
[ // this signifies that the vertical and horizontal adjectives
// can be arbitrarily ordered, however, there can only be two,
// one of each, or none at all
[
left | center | right
] ||
[
top | center | bottom
]
]
top, left = 0%
center, (none) = 50%
bottom, right = 100%
*/
/* QuirksMode says:
keyword + length/percentage must be ordered correctly, as per W3C
Internet Explorer and Opera, however, support arbitrary ordering. We
should fix it up.
Minor issue though, not strictly necessary.
*/
// control freaks may appreciate the ability to convert these to
// percentages or something, but it's not necessary
/**
* Validates the value of background-position.
*/
class HTMLPurifier_AttrDef_CSS_BackgroundPosition extends HTMLPurifier_AttrDef
{
var $length;
var $percentage;
function HTMLPurifier_AttrDef_CSS_BackgroundPosition() {
$this->length = new HTMLPurifier_AttrDef_CSS_Length();
$this->percentage = new HTMLPurifier_AttrDef_CSS_Percentage();
}
function validate($string, $config, &$context) {
$string = $this->parseCDATA($string);
$bits = explode(' ', $string);
$keywords = array();
$keywords['h'] = false; // left, right
$keywords['v'] = false; // top, bottom
$keywords['c'] = false; // center
$measures = array();
$i = 0;
$lookup = array(
'top' => 'v',
'bottom' => 'v',
'left' => 'h',
'right' => 'h',
'center' => 'c'
);
foreach ($bits as $bit) {
if ($bit === '') continue;
// test for keyword
$lbit = ctype_lower($bit) ? $bit : strtolower($bit);
if (isset($lookup[$lbit])) {
$status = $lookup[$lbit];
$keywords[$status] = $lbit;
$i++;
}
// test for length
$r = $this->length->validate($bit, $config, $context);
if ($r !== false) {
$measures[] = $r;
$i++;
}
// test for percentage
$r = $this->percentage->validate($bit, $config, $context);
if ($r !== false) {
$measures[] = $r;
$i++;
}
}
if (!$i) return false; // no valid values were caught
$ret = array();
// first keyword
if ($keywords['h']) $ret[] = $keywords['h'];
elseif (count($measures)) $ret[] = array_shift($measures);
elseif ($keywords['c']) {
$ret[] = $keywords['c'];
$keywords['c'] = false; // prevent re-use: center = center center
}
if ($keywords['v']) $ret[] = $keywords['v'];
elseif (count($measures)) $ret[] = array_shift($measures);
elseif ($keywords['c']) $ret[] = $keywords['c'];
if (empty($ret)) return false;
return implode(' ', $ret);
}
}
?>

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<?php
require_once 'HTMLPurifier/AttrDef.php';
/**
* Validates the border property as defined by CSS.
*/
class HTMLPurifier_AttrDef_CSS_Border extends HTMLPurifier_AttrDef
{
/**
* Local copy of properties this property is shorthand for.
*/
var $info = array();
function HTMLPurifier_AttrDef_CSS_Border($config) {
$def = $config->getCSSDefinition();
$this->info['border-width'] = $def->info['border-width'];
$this->info['border-style'] = $def->info['border-style'];
$this->info['border-top-color'] = $def->info['border-top-color'];
}
function validate($string, $config, &$context) {
$string = $this->parseCDATA($string);
// we specifically will not support rgb() syntax with spaces
$bits = explode(' ', $string);
$done = array(); // segments we've finished
$ret = ''; // return value
foreach ($bits as $bit) {
foreach ($this->info as $propname => $validator) {
if (isset($done[$propname])) continue;
$r = $validator->validate($bit, $config, $context);
if ($r !== false) {
$ret .= $r . ' ';
$done[$propname] = true;
break;
}
}
}
return rtrim($ret);
}
}
?>

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<?php
require_once 'HTMLPurifier/AttrDef.php';
/**
* Validates Color as defined by CSS.
*/
class HTMLPurifier_AttrDef_CSS_Color extends HTMLPurifier_AttrDef
{
/**
* Color keyword lookup table.
* @todo Extend it to include all usually allowed colors.
*/
var $colors = array(
'maroon' => '#800000',
'red' => '#F00',
'orange' => '#FFA500',
'yellow' => '#FF0',
'olive' => '#808000',
'purple' => '#800080',
'fuchsia' => '#F0F',
'white' => '#FFF',
'lime' => '#0F0',
'green' => '#008000',
'navy' => '#000080',
'blue' => '#00F',
'aqua' => '#0FF',
'teal' => '#008080',
'black' => '#000',
'silver' => '#C0C0C0',
'gray' => '#808080'
);
function validate($color, $config, &$context) {
$color = trim($color);
if (!$color) return false;
$lower = strtolower($color);
if (isset($this->colors[$lower])) return $this->colors[$lower];
if ($color[0] === '#') {
// hexadecimal handling
$hex = substr($color, 1);
$length = strlen($hex);
if ($length !== 3 && $length !== 6) return false;
if (!ctype_xdigit($hex)) return false;
} else {
// rgb literal handling
if (strpos($color, 'rgb(')) return false;
$length = strlen($color);
if (strpos($color, ')') !== $length - 1) return false;
$triad = substr($color, 4, $length - 4 - 1);
$parts = explode(',', $triad);
if (count($parts) !== 3) return false;
$type = false; // to ensure that they're all the same type
$new_parts = array();
foreach ($parts as $part) {
$part = trim($part);
if ($part === '') return false;
$length = strlen($part);
if ($part[$length - 1] === '%') {
// handle percents
if (!$type) {
$type = 'percentage';
} elseif ($type !== 'percentage') {
return false;
}
$num = (float) substr($part, 0, $length - 1);
if ($num < 0) $num = 0;
if ($num > 100) $num = 100;
$new_parts[] = "$num%";
} else {
// handle integers
if (!$type) {
$type = 'integer';
} elseif ($type !== 'integer') {
return false;
}
$num = (int) $part;
if ($num < 0) $num = 0;
if ($num > 255) $num = 255;
$new_parts[] = (string) $num;
}
}
$new_triad = implode(',', $new_parts);
$color = "rgb($new_triad)";
}
return $color;
}
}
?>

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<?php
/**
* Allows multiple validators to attempt to validate attribute.
*
* Composite is just what it sounds like: a composite of many validators.
* This means that multiple HTMLPurifier_AttrDef objects will have a whack
* at the string. If one of them passes, that's what is returned. This is
* especially useful for CSS values, which often are a choice between
* an enumerated set of predefined values or a flexible data type.
*/
class HTMLPurifier_AttrDef_CSS_Composite extends HTMLPurifier_AttrDef
{
/**
* List of HTMLPurifier_AttrDef objects that may process strings
* @protected
*/
var $defs;
/**
* @param $defs List of HTMLPurifier_AttrDef objects
*/
function HTMLPurifier_AttrDef_CSS_Composite($defs) {
$this->defs = $defs;
}
function validate($string, $config, &$context) {
foreach ($this->defs as $i => $def) {
$result = $this->defs[$i]->validate($string, $config, $context);
if ($result !== false) return $result;
}
return false;
}
}
?>

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<?php
require_once 'HTMLPurifier/AttrDef.php';
/**
* Validates shorthand CSS property font.
*/
class HTMLPurifier_AttrDef_CSS_Font extends HTMLPurifier_AttrDef
{
/**
* Local copy of component validators.
*
* @note If we moved specific CSS property definitions to their own
* classes instead of having them be assembled at run time by
* CSSDefinition, this wouldn't be necessary. We'd instantiate
* our own copies.
*/
var $info = array();
/**
* System font keywords.
*/
var $system_fonts = array(
'caption' => true,
'icon' => true,
'menu' => true,
'message-box' => true,
'small-caption' => true,
'status-bar' => true
);
function HTMLPurifier_AttrDef_CSS_Font($config) {
$def = $config->getCSSDefinition();
$this->info['font-style'] = $def->info['font-style'];
$this->info['font-variant'] = $def->info['font-variant'];
$this->info['font-weight'] = $def->info['font-weight'];
$this->info['font-size'] = $def->info['font-size'];
$this->info['line-height'] = $def->info['line-height'];
$this->info['font-family'] = $def->info['font-family'];
}
function validate($string, $config, &$context) {
// regular pre-processing
$string = $this->parseCDATA($string);
if ($string === '') return false;
// check if it's one of the keywords
$lowercase_string = strtolower($string);
if (isset($this->system_fonts[$lowercase_string])) {
return $lowercase_string;
}
$bits = explode(' ', $string); // bits to process
$stage = 0; // this indicates what we're looking for
$caught = array(); // which stage 0 properties have we caught?
$stage_1 = array('font-style', 'font-variant', 'font-weight');
$final = ''; // output
for ($i = 0, $size = count($bits); $i < $size; $i++) {
if ($bits[$i] === '') continue;
switch ($stage) {
// attempting to catch font-style, font-variant or font-weight
case 0:
foreach ($stage_1 as $validator_name) {
if (isset($caught[$validator_name])) continue;
$r = $this->info[$validator_name]->validate(
$bits[$i], $config, $context);
if ($r !== false) {
$final .= $r . ' ';
$caught[$validator_name] = true;
break;
}
}
// all three caught, continue on
if (count($caught) >= 3) $stage = 1;
if ($r !== false) break;
// attempting to catch font-size and perhaps line-height
case 1:
$found_slash = false;
if (strpos($bits[$i], '/') !== false) {
list($font_size, $line_height) =
explode('/', $bits[$i]);
if ($line_height === '') {
// ooh, there's a space after the slash!
$line_height = false;
$found_slash = true;
}
} else {
$font_size = $bits[$i];
$line_height = false;
}
$r = $this->info['font-size']->validate(
$font_size, $config, $context);
if ($r !== false) {
$final .= $r;
// attempt to catch line-height
if ($line_height === false) {
// we need to scroll forward
for ($j = $i + 1; $j < $size; $j++) {
if ($bits[$j] === '') continue;
if ($bits[$j] === '/') {
if ($found_slash) {
return false;
} else {
$found_slash = true;
continue;
}
}
$line_height = $bits[$j];
break;
}
} else {
// slash already found
$found_slash = true;
$j = $i;
}
if ($found_slash) {
$i = $j;
$r = $this->info['line-height']->validate(
$line_height, $config, $context);
if ($r !== false) {
$final .= '/' . $r;
}
}
$final .= ' ';
$stage = 2;
break;
}
return false;
// attempting to catch font-family
case 2:
$font_family =
implode(' ', array_slice($bits, $i, $size - $i));
$r = $this->info['font-family']->validate(
$font_family, $config, $context);
if ($r !== false) {
$final .= $r . ' ';
// processing completed successfully
return rtrim($final);
}
return false;
}
}
return false;
}
}
?>

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<?php
require_once 'HTMLPurifier/AttrDef.php';
// whitelisting allowed fonts would be nice
/**
* Validates a font family list according to CSS spec
*/
class HTMLPurifier_AttrDef_CSS_FontFamily extends HTMLPurifier_AttrDef
{
/**
* Generic font family keywords.
* @protected
*/
var $generic_names = array(
'serif' => true,
'sans-serif' => true,
'monospace' => true,
'fantasy' => true,
'cursive' => true
);
function validate($string, $config, &$context) {
$string = $this->parseCDATA($string);
// assume that no font names contain commas in them
$fonts = explode(',', $string);
$final = '';
foreach($fonts as $font) {
$font = trim($font);
if ($font === '') continue;
// match a generic name
if (isset($this->generic_names[$font])) {
$final .= $font . ', ';
continue;
}
// match a quoted name
if ($font[0] === '"' || $font[0] === "'") {
$length = strlen($font);
if ($length <= 2) continue;
$quote = $font[0];
if ($font[$length - 1] !== $quote) continue;
$font = substr($font, 1, $length - 2);
}
// process font
if (ctype_alnum($font)) {
// very simple font, allow it in unharmed
$final .= $font . ', ';
continue;
}
$nospace = str_replace(array(' ', '.', '!'), '', $font);
if (ctype_alnum($nospace)) {
// font with spaces in it
$final .= "'$font', ";
continue;
}
}
$final = rtrim($final, ', ');
if ($final === '') return false;
return $final;
}
}
?>

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<?php
require_once 'HTMLPurifier/AttrDef.php';
require_once 'HTMLPurifier/AttrDef/CSS/Number.php';
/**
* Represents a Length as defined by CSS.
*/
class HTMLPurifier_AttrDef_CSS_Length extends HTMLPurifier_AttrDef
{
/**
* Valid unit lookup table.
* @warning The code assumes all units are two characters long. Be careful
* if we have to change this behavior!
*/
var $units = array('em' => true, 'ex' => true, 'px' => true, 'in' => true,
'cm' => true, 'mm' => true, 'pt' => true, 'pc' => true);
/**
* Instance of HTMLPurifier_AttrDef_Number to defer number validation to
*/
var $number_def;
/**
* @param $non_negative Bool indication whether or not negative values are
* allowed.
*/
function HTMLPurifier_AttrDef_CSS_Length($non_negative = false) {
$this->number_def = new HTMLPurifier_AttrDef_CSS_Number($non_negative);
}
function validate($length, $config, &$context) {
$length = $this->parseCDATA($length);
if ($length === '') return false;
if ($length === '0') return '0';
$strlen = strlen($length);
if ($strlen === 1) return false; // impossible!
// we assume all units are two characters
$unit = substr($length, $strlen - 2);
if (!ctype_lower($unit)) $unit = strtolower($unit);
$number = substr($length, 0, $strlen - 2);
if (!isset($this->units[$unit])) return false;
$number = $this->number_def->validate($number, $config, $context);
if ($number === false) return false;
return $number . $unit;
}
}
?>

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<?php
require_once 'HTMLPurifier/AttrDef.php';
/**
* Validates shorthand CSS property list-style.
* @warning Does not support url tokens that have internal spaces.
*/
class HTMLPurifier_AttrDef_CSS_ListStyle extends HTMLPurifier_AttrDef
{
/**
* Local copy of component validators.
* @note See HTMLPurifier_AttrDef_CSS_Font::$info for a similar impl.
*/
var $info;
function HTMLPurifier_AttrDef_CSS_ListStyle($config) {
$def = $config->getCSSDefinition();
$this->info['list-style-type'] = $def->info['list-style-type'];
$this->info['list-style-position'] = $def->info['list-style-position'];
$this->info['list-style-image'] = $def->info['list-style-image'];
}
function validate($string, $config, &$context) {
// regular pre-processing
$string = $this->parseCDATA($string);
if ($string === '') return false;
// assumes URI doesn't have spaces in it
$bits = explode(' ', strtolower($string)); // bits to process
$caught = array();
$caught['type'] = false;
$caught['position'] = false;
$caught['image'] = false;
$i = 0; // number of catches
$none = false;
foreach ($bits as $bit) {
if ($i >= 3) return; // optimization bit
if ($bit === '') continue;
foreach ($caught as $key => $status) {
if ($status !== false) continue;
$r = $this->info['list-style-' . $key]->validate($bit, $config, $context);
if ($r === false) continue;
if ($r === 'none') {
if ($none) continue;
else $none = true;
if ($key == 'image') continue;
}
$caught[$key] = $r;
$i++;
break;
}
}
if (!$i) return false;
$ret = array();
// construct type
if ($caught['type']) $ret[] = $caught['type'];
// construct image
if ($caught['image']) $ret[] = $caught['image'];
// construct position
if ($caught['position']) $ret[] = $caught['position'];
if (empty($ret)) return false;
return implode(' ', $ret);
}
}
?>

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<?php
require_once 'HTMLPurifier/AttrDef.php';
/**
* Framework class for strings that involve multiple values.
*
* Certain CSS properties such as border-width and margin allow multiple
* lengths to be specified. This class can take a vanilla border-width
* definition and multiply it, usually into a max of four.
*
* @note Even though the CSS specification isn't clear about it, inherit
* can only be used alone: it will never manifest as part of a multi
* shorthand declaration. Thus, this class does not allow inherit.
*/
class HTMLPurifier_AttrDef_CSS_Multiple extends HTMLPurifier_AttrDef
{
/**
* Instance of component definition to defer validation to.
*/
var $single;
/**
* Max number of values allowed.
*/
var $max;
/**
* @param $single HTMLPurifier_AttrDef to multiply
* @param $max Max number of values allowed (usually four)
*/
function HTMLPurifier_AttrDef_CSS_Multiple($single, $max = 4) {
$this->single = $single;
$this->max = $max;
}
function validate($string, $config, &$context) {
$string = $this->parseCDATA($string);
if ($string === '') return false;
$parts = explode(' ', $string); // parseCDATA replaced \r, \t and \n
$length = count($parts);
$final = '';
for ($i = 0, $num = 0; $i < $length && $num < $this->max; $i++) {
if (ctype_space($parts[$i])) continue;
$result = $this->single->validate($parts[$i], $config, $context);
if ($result !== false) {
$final .= $result . ' ';
$num++;
}
}
if ($final === '') return false;
return rtrim($final);
}
}
?>

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<?php
/**
* Validates a number as defined by the CSS spec.
*/
class HTMLPurifier_AttrDef_CSS_Number extends HTMLPurifier_AttrDef
{
/**
* Bool indicating whether or not only positive values allowed.
*/
var $non_negative = false;
/**
* @param $non_negative Bool indicating whether negatives are forbidden
*/
function HTMLPurifier_AttrDef_CSS_Number($non_negative = false) {
$this->non_negative = $non_negative;
}
function validate($number, $config, &$context) {
$number = $this->parseCDATA($number);
if ($number === '') return false;
$sign = '';
switch ($number[0]) {
case '-':
if ($this->non_negative) return false;
$sign = '-';
case '+':
$number = substr($number, 1);
}
if (ctype_digit($number)) {
$number = ltrim($number, '0');
return $number ? $sign . $number : '0';
}
if (!strpos($number, '.')) return false;
list($left, $right) = explode('.', $number, 2);
if (!ctype_digit($left)) return false;
$left = ltrim($left, '0');
$right = rtrim($right, '0');
if ($right === '') {
return $left ? $sign . $left : '0';
} elseif (!ctype_digit($right)) {
return false;
}
return $sign . $left . '.' . $right;
}
}
?>

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<?php
require_once 'HTMLPurifier/AttrDef.php';
require_once 'HTMLPurifier/AttrDef/CSS/Number.php';
/**
* Validates a Percentage as defined by the CSS spec.
*/
class HTMLPurifier_AttrDef_CSS_Percentage extends HTMLPurifier_AttrDef
{
/**
* Instance of HTMLPurifier_AttrDef_CSS_Number to defer number validation
*/
var $number_def;
/**
* @param Bool indicating whether to forbid negative values
*/
function HTMLPurifier_AttrDef_CSS_Percentage($non_negative = false) {
$this->number_def = new HTMLPurifier_AttrDef_CSS_Number($non_negative);
}
function validate($string, $config, &$context) {
$string = $this->parseCDATA($string);
if ($string === '') return false;
$length = strlen($string);
if ($length === 1) return false;
if ($string[$length - 1] !== '%') return false;
$number = substr($string, 0, $length - 1);
$number = $this->number_def->validate($number, $config, $context);
if ($number === false) return false;
return "$number%";
}
}
?>

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<?php
require_once 'HTMLPurifier/AttrDef.php';
/**
* Validates the value for the CSS property text-decoration
* @note This class could be generalized into a version that acts sort of
* like Enum except you can compound the allowed values.
*/
class HTMLPurifier_AttrDef_CSS_TextDecoration extends HTMLPurifier_AttrDef
{
/**
* Lookup table of allowed values.
* @protected
*/
var $allowed_values = array(
'line-through' => true,
'overline' => true,
'underline' => true
);
function validate($string, $config, &$context) {
$string = strtolower($this->parseCDATA($string));
$parts = explode(' ', $string);
$final = '';
foreach ($parts as $part) {
if (isset($this->allowed_values[$part])) {
$final .= $part . ' ';
}
}
$final = rtrim($final);
if ($final === '') return false;
return $final;
}
}
?>

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<?php
require_once 'HTMLPurifier/AttrDef/URI.php';
/**
* Validates a URI in CSS syntax, which uses url('http://example.com')
* @note While theoretically speaking a URI in a CSS document could
* be non-embedded, as of CSS2 there is no such usage so we're
* generalizing it. This may need to be changed in the future.
* @warning Since HTMLPurifier_AttrDef_CSS blindly uses semicolons as
* the separator, you cannot put a literal semicolon in
* in the URI. Try percent encoding it, in that case.
*/
class HTMLPurifier_AttrDef_CSS_URI extends HTMLPurifier_AttrDef_URI
{
function HTMLPurifier_AttrDef_CSS_URI() {
$this->HTMLPurifier_AttrDef_URI(true); // always embedded
}
function validate($uri_string, $config, &$context) {
// parse the URI out of the string and then pass it onto
// the parent object
$uri_string = $this->parseCDATA($uri_string);
if (strpos($uri_string, 'url(') !== 0) return false;
$uri_string = substr($uri_string, 4);
$new_length = strlen($uri_string) - 1;
if ($uri_string[$new_length] != ')') return false;
$uri = trim(substr($uri_string, 0, $new_length));
if (isset($uri[0]) && ($uri[0] == "'" || $uri[0] == '"')) {
$quote = $uri[0];
$new_length = strlen($uri) - 1;
if ($uri[$new_length] !== $quote) return false;
$uri = substr($uri, 1, $new_length - 1);
}
$keys = array( '(', ')', ',', ' ', '"', "'");
$values = array('\\(', '\\)', '\\,', '\\ ', '\\"', "\\'");
$uri = str_replace($values, $keys, $uri);
$result = parent::validate($uri, $config, $context);
if ($result === false) return false;
// escape necessary characters according to CSS spec
// except for the comma, none of these should appear in the
// URI at all
$result = str_replace($keys, $values, $result);
return "url($result)";
}
}
?>