File indexing completed on 2024-12-22 05:36:18

 <?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
     }
 
     /**
      * @param string $uri_string
      * @param HTMLPurifier_Config $config
      * @param HTMLPurifier_Context $context
      * @return bool|string
      */
     public function validate($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);
         if (strlen($uri_string) == 0) {
             return false;
         }
         $new_length = strlen($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);
 
         // suspicious characters are ()'; we're going to percent encode
         // them for safety.
         $result = str_replace(array('(', ')', "'"), array('%28', '%29', '%27'), $result);
 
         // there's an extra bug where ampersands lose their escaping on
         // an innerHTML cycle, so a very unlucky query parameter could
         // then change the meaning of the URL.  Unfortunately, there's
         // not much we can do about that...
         return "url(\"$result\")";
     }
 }
 
 // vim: et sw=4 sts=4