<?php
/*
* This file is part of Twig.
*
* (c) 2009 Fabien Potencier
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
/**
* Twig_NodeVisitor_Sandbox implements sandboxing.
*
* @package twig
* @author Fabien Potencier <fabien@symfony.com>
*/
class Twig_NodeVisitor_Sandbox implements Twig_NodeVisitorInterface
{
protected $inAModule = false;
protected $tags;
protected $filters;
protected $functions;
/**
* Called before child nodes are visited.
*
* @param Twig_NodeInterface $node The node to visit
* @param Twig_Environment $env The Twig environment instance
*
* @return Twig_NodeInterface The modified node
*/
public function enterNode(Twig_NodeInterface $node, Twig_Environment $env)
{
// in a sandbox tag, only include tags are allowed
if ($node instanceof Twig_Node_Sandbox && !$node->getNode('body') instanceof Twig_Node_Include) {
foreach ($node->getNode('body') as $n) {
if ($n instanceof Twig_Node_Text && ctype_space($n->getAttribute('data'))) {
continue;
}
if (!$n instanceof Twig_Node_Include) {
throw new Twig_Error_Syntax('Only "include" tags are allowed within a "sandbox" section', $n->getLine());
}
}
}
if ($node instanceof Twig_Node_Module) {
$this->inAModule = true;
$this->tags = array();
$this->filters = array();
$this->functions = array();
return $node;
} elseif ($this->inAModule) {
// look for tags
if ($node->getNodeTag()) {
$this->tags[] = $node->getNodeTag();
}
// look for filters
if ($node instanceof Twig_Node_Expression_Filter) {
$this->filters[] = $node->getNode('filter')->getAttribute('value');
}
// look for functions
if ($node instanceof Twig_Node_Expression_Function) {
$this->functions[] = $node->getAttribute('name');
}
// wrap print to check __toString() calls
if ($node instanceof Twig_Node_Print) {
return new Twig_Node_SandboxedPrint($node->getNode('expr'), $node->getLine(), $node->getNodeTag());
}
}
return $node;
}
/**
* Called after child nodes are visited.
*
* @param Twig_NodeInterface $node The node to visit
* @param Twig_Environment $env The Twig environment instance
*
* @return Twig_NodeInterface The modified node
*/
public function leaveNode(Twig_NodeInterface $node, Twig_Environment $env)
{
if ($node instanceof Twig_Node_Module) {
$this->inAModule = false;
return new Twig_Node_SandboxedModule($node, array_unique($this->filters), array_unique($this->tags), array_unique($this->functions));
}
return $node;
}
/**
* {@inheritdoc}
*/
public function getPriority()
{
return 0;
}
}