<?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 { public function __construct() { parent::__construct(true); // always embedded } public 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, $new_length)); if (!empty($uri) && ($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); } $uri = $this->expandCSSEscape($uri); $result = parent::validate($uri, $config, $context); if ($result === false) return false; // extra sanity check; should have been done by URI $result = str_replace(array('"', "\\", "\n", "\x0c", "\r"), "", $result); return "url(\"$result\")"; } } // vim: et sw=4 sts=4