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 $allowedParam = array(
  21         'wmode' => true,
  22         'movie' => true,
  23         'flashvars' => true,
  24         'src' => true,
  25     );
  26
  27     public function prepare($config, $context) {
  28         parent::prepare($config, $context);
  29     }
  30
  31     public function handleElement(&$token) {
  32         if ($token->name == 'object') {
  33             $this->objectStack[] = $token;
  34             $this->paramStack[] = array();
  35             $new = array($token);
  36             foreach ($this->addParam as $name => $value) {
  37                 $new[] = new HTMLPurifier_Token_Empty('param', array('name' => $name, 'value' => $value));
  38             }
  39             $token = $new;
  40         } elseif ($token->name == 'param') {
  41             $nest = count($this->currentNesting) - 1;
  42             if ($nest >= 0 && $this->currentNesting[$nest]->name === 'object') {
  43                 $i = count($this->objectStack) - 1;
  44                 if (!isset($token->attr['name'])) {
  45                     $token = false;
  46                     return;
  47                 }
  48                 $n = $token->attr['name'];
  49                 // We need this fix because YouTube doesn't supply a data
  50                 // attribute, which we need if a type is specified. This is
  51                 // *very* Flash specific.
  52                 if (!isset($this->objectStack[$i]->attr['data']) &&
  53                     ($token->attr['name'] == 'movie' || $token->attr['name'] == 'src')) {
  54                     $this->objectStack[$i]->attr['data'] = $token->attr['value'];
  55                 }
  56                 // Check if the parameter is the correct value but has not
  57                 // already been added
  58                 if (
  59                     !isset($this->paramStack[$i][$n]) &&
  60                     isset($this->addParam[$n]) &&
  61                     $token->attr['name'] === $this->addParam[$n]
  62                 ) {
  63                     // keep token, and add to param stack
  64                     $this->paramStack[$i][$n] = true;
  65                 } elseif (isset($this->allowedParam[$n])) {
  66                     // keep token, don't do anything to it
  67                     // (could possibly check for duplicates here)
  68                 } else {
  69                     $token = false;
  70                 }
  71             } else {
  72                 // not directly inside an object, DENY!
  73                 $token = false;
  74             }
  75         }
  76     }
  77
  78     public function handleEnd(&$token) {
  79         // This is the WRONG way of handling the object and param stacks;
  80         // we should be inserting them directly on the relevant object tokens
  81         // so that the global stack handling handles it.
  82         if ($token->name == 'object') {
  83             array_pop($this->objectStack);
  84             array_pop($this->paramStack);
  85         }
  86     }
  87
  88 }
  89
  90 // vim: et sw=4 sts=4