0
0
mirror of https://github.com/ezyang/htmlpurifier.git synced 2024-12-23 08:51:53 +00:00
htmlpurifier/library/HTMLPurifier/AttrDef/CSSURI.php

58 lines
2.0 KiB
PHP
Raw Normal View History

<?php
require_once 'HTMLPurifier/AttrDef/URI.php';
/**
* Validates a URI in CSS syntax, which uses url('http://example.com')
* @note While theoretically speaking we 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_CSSURI extends HTMLPurifier_AttrDef_URI
{
function HTMLPurifier_AttrDef_CSSURI() {
$this->HTMLPurifier_AttrDef_URI(true); // always embedded
}
function validate($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)";
}
}
?>