[3.1.1] Implement SafeObject.

git-svn-id: http://htmlpurifier.org/svnroot/htmlpurifier/trunk@1780 48356398-32a2-884e-a903-53898d9a118a

library/HTMLPurifier/Injector/SafeObject.php

@@ -0,0 +1,77 @@
+<?php
+
+/**
+ * Adds important param elements to inside of object in order to make
+ * things safe.
+ */
+class HTMLPurifier_Injector_SafeObject extends HTMLPurifier_Injector
+{
+    public $name = 'SafeObject';
+    public $needed = array('object', 'param');
+    
+    protected $objectStack = array();
+    protected $paramStack  = array();
+    
+    // Keep this synchronized with AttrTransform/SafeParam.php
+    protected $addParam = array(
+        'allowScriptAccess' => 'never',
+        'allowNetworking' => 'internal',
+    );
+    protected $allowedParam = array(
+        'wmode' => true,
+        'movie' => true,
+    );
+    
+    public function prepare($config, $context) {
+        parent::prepare($config, $context);
+    }
+    
+    public function handleElement(&$token) {
+        if ($token->name == 'object') {
+            $this->objectStack[] = $token;
+            $this->paramStack[] = array();
+            $new = array($token);
+            foreach ($this->addParam as $name => $value) {
+                $new[] = new HTMLPurifier_Token_Empty('param', array('name' => $name, 'value' => $value));
+            }
+            $token = $new;
+        } elseif ($token->name == 'param') {
+            $nest = count($this->currentNesting) - 1;
+            if ($nest >= 0 && $this->currentNesting[$nest]->name === 'object') {
+                $i = count($this->objectStack) - 1;
+                if (!isset($token->attr['name'])) {
+                    $token = false;
+                    return;
+                }
+                $n = $token->attr['name'];
+                // Check if the parameter is the correct value but has not
+                // already been added
+                if (
+                    !isset($this->paramStack[$i][$n]) &&
+                    isset($this->addParam[$n]) &&
+                    $token->attr['name'] === $this->addParam[$n]
+                ) {
+                    // keep token, and add to param stack
+                    $this->paramStack[$i][$n] = true;
+                } elseif (isset($this->allowedParam[$n])) {
+                    // keep token, don't do anything to it
+                    // (could possibly check for duplicates here)
+                } else {
+                    $token = false;
+                }
+            } else {
+                // not directly inside an object, DENY!
+                $token = false;
+            }
+        }
+    }
+    
+    public function notifyEnd($token) {
+        if ($token->name == 'object') {
+            array_pop($this->objectStack);
+            array_pop($this->paramStack);
+        }
+    }
+    
+}
+