library/HTMLPurifier/Injector/SafeObject.php

   1 <?php
   2
   3 /**
   4  * Adds important param elements to inside of object in order to make
   5  * things safe.
   6  */
   7 class HTMLPurifier_Injector_SafeObject extends HTMLPurifier_Injector
   8 {
   9     public $name = 'SafeObject';
  10     public $needed = array('object', 'param');
  11
  12     protected $objectStack = array();
  13     protected $paramStack  = array();
  14
  15     // Keep this synchronized with AttrTransform/SafeParam.php
  16     protected $addParam = array(
  17         'allowScriptAccess' => 'never',
  18         'allowNetworking' => 'internal',
  19     );
  20     protected $allowedParam = array(
  21         'wmode' => true,
  22         'movie' => true,
  23     );
  24
  25     public function prepare($config, $context) {
  26         parent::prepare($config, $context);
  27     }
  28
  29     public function handleElement(&$token) {
  30         if ($token->name == 'object') {
  31             $this->objectStack[] = $token;
  32             $this->paramStack[] = array();
  33             $new = array($token);
  34             foreach ($this->addParam as $name => $value) {
  35                 $new[] = new HTMLPurifier_Token_Empty('param', array('name' => $name, 'value' => $value));
  36             }
  37             $token = $new;
  38         } elseif ($token->name == 'param') {
  39             $nest = count($this->currentNesting) - 1;
  40             if ($nest >= 0 && $this->currentNesting[$nest]->name === 'object') {
  41                 $i = count($this->objectStack) - 1;
  42                 if (!isset($token->attr['name'])) {
  43                     $token = false;
  44                     return;
  45                 }
  46                 $n = $token->attr['name'];
  47                 // Check if the parameter is the correct value but has not
  48                 // already been added
  49                 if (
  50                     !isset($this->paramStack[$i][$n]) &&
  51                     isset($this->addParam[$n]) &&
  52                     $token->attr['name'] === $this->addParam[$n]
  53                 ) {
  54                     // keep token, and add to param stack
  55                     $this->paramStack[$i][$n] = true;
  56                 } elseif (isset($this->allowedParam[$n])) {
  57                     // keep token, don't do anything to it
  58                     // (could possibly check for duplicates here)
  59                 } else {
  60                     $token = false;
  61                 }
  62             } else {
  63                 // not directly inside an object, DENY!
  64                 $token = false;
  65             }
  66         }
  67     }
  68
  69     public function notifyEnd($token) {
  70         if ($token->name == 'object') {
  71             array_pop($this->objectStack);
  72             array_pop($this->paramStack);
  73         }
  74     }
  75
  76 }
  77