<?php
/*
* This file is part of Twig.
*
* (c) Fabien Potencier
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
namespace Twig\NodeVisitor;
use Twig\Environment;
use Twig\Node\CheckSecurityCallNode;
use Twig\Node\CheckSecurityNode;
use Twig\Node\CheckToStringNode;
use Twig\Node\Expression\Binary\ConcatBinary;
use Twig\Node\Expression\Binary\RangeBinary;
use Twig\Node\Expression\FilterExpression;
use Twig\Node\Expression\FunctionExpression;
use Twig\Node\Expression\GetAttrExpression;
use Twig\Node\Expression\NameExpression;
use Twig\Node\ModuleNode;
use Twig\Node\Node;
use Twig\Node\PrintNode;
use Twig\Node\SetNode;
/**
* @author Fabien Potencier <fabien@symfony.com>
*
* @internal
*/
final class SandboxNodeVisitor implements NodeVisitorInterface
{
private $inAModule = false;
private $tags;
private $filters;
private $functions;
private $needsToStringWrap = false;
public function enterNode(Node $node, Environment $env): Node
{
if ($node instanceof ModuleNode) {
$this->inAModule = true;
$this->tags = [];
$this->filters = [];
$this->functions = [];
return $node;
} elseif ($this->inAModule) {
// look for tags
if ($node->getNodeTag() && !isset($this->tags[$node->getNodeTag()])) {
$this->tags[$node->getNodeTag()] = $node;
}
// look for filters
if ($node instanceof FilterExpression && !isset($this->filters[$node->getNode('filter')->getAttribute('value')])) {
$this->filters[$node->getNode('filter')->getAttribute('value')] = $node;
}
// look for functions
if ($node instanceof FunctionExpression && !isset($this->functions[$node->getAttribute('name')])) {
$this->functions[$node->getAttribute('name')] = $node;
}
// the .. operator is equivalent to the range() function
if ($node instanceof RangeBinary && !isset($this->functions['range'])) {
$this->functions['range'] = $node;
}
if ($node instanceof PrintNode) {
$this->needsToStringWrap = true;
$this->wrapNode($node, 'expr');
}
if ($node instanceof SetNode && !$node->getAttribute('capture')) {
$this->needsToStringWrap = true;
}
// wrap outer nodes that can implicitly call __toString()
if ($this->needsToStringWrap) {
if ($node instanceof ConcatBinary) {
$this->wrapNode($node, 'left');
$this->wrapNode($node, 'right');
}
if ($node instanceof FilterExpression) {
$this->wrapNode($node, 'node');
$this->wrapArrayNode($node, 'arguments');
}
if ($node instanceof FunctionExpression) {
$this->wrapArrayNode($node, 'arguments');
}
}
}
return $node;
}
public function leaveNode(Node $node, Environment $env): ?Node
{
if ($node instanceof ModuleNode) {
$this->inAModule = false;
$node->setNode('constructor_end', new Node([new CheckSecurityCallNode(), $node->getNode('constructor_end')]));
$node->setNode('class_end', new Node([new CheckSecurityNode($this->filters, $this->tags, $this->functions), $node->getNode('class_end')]));
} elseif ($this->inAModule) {
if ($node instanceof PrintNode || $node instanceof SetNode) {
$this->needsToStringWrap = false;
}
}
return $node;
}
private function wrapNode(Node $node, string $name): void
{
$expr = $node->getNode($name);
if ($expr instanceof NameExpression || $expr instanceof GetAttrExpression) {
$node->setNode($name, new CheckToStringNode($expr));
}
}
private function wrapArrayNode(Node $node, string $name): void
{
$args = $node->getNode($name);
foreach ($args as $name => $_) {
$this->wrapNode($args, $name);
}
}
public function getPriority(): int
{
return 0;
}
}