library/HTMLPurifier/AttrDef/HTML/LinkTypes.php

   1 <?php
   2
   3 /**
   4  * Validates a rel/rev link attribute against a directive of allowed values
   5  * @note We cannot use Enum because link types allow multiple
   6  *       values.
   7  * @note Assumes link types are ASCII text
   8  */
   9 class HTMLPurifier_AttrDef_HTML_LinkTypes extends HTMLPurifier_AttrDef
  10 {
  11
  12     /** Name config attribute to pull. */
  13     protected $name;
  14
  15     public function __construct($name) {
  16         $configLookup = array(
  17             'rel' => 'AllowedRel',
  18             'rev' => 'AllowedRev'
  19         );
  20         if (!isset($configLookup[$name])) {
  21             trigger_error('Unrecognized attribute name for link '.
  22                 'relationship.', E_USER_ERROR);
  23             return;
  24         }
  25         $this->name = $configLookup[$name];
  26     }
  27
  28     public function validate($string, $config, $context) {
  29
  30         $allowed = $config->get('Attr', $this->name);
  31         if (empty($allowed)) return false;
  32
  33         $string = $this->parseCDATA($string);
  34         $parts = explode(' ', $string);
  35
  36         // lookup to prevent duplicates
  37         $ret_lookup = array();
  38         foreach ($parts as $part) {
  39             $part = strtolower(trim($part));
  40             if (!isset($allowed[$part])) continue;
  41             $ret_lookup[$part] = true;
  42         }
  43
  44         if (empty($ret_lookup)) return false;
  45         $string = implode(' ', array_keys($ret_lookup));
  46
  47         return $string;
  48
  49     }
  50
  51 }
  52
  53 // vim: et sw=4 sts=4