Added an "twig" lines mode, where the label lines are processed via a sandboxed twig.

src/Twig/Sandbox/InheritanceSecurityPolicy.php

@@ -0,0 +1,140 @@
+<?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 App\Twig\Sandbox;
+
+use Twig\Markup;
+use Twig\Sandbox\SecurityNotAllowedFilterError;
+use Twig\Sandbox\SecurityNotAllowedFunctionError;
+use Twig\Sandbox\SecurityNotAllowedMethodError;
+use Twig\Sandbox\SecurityNotAllowedPropertyError;
+use Twig\Sandbox\SecurityNotAllowedTagError;
+use Twig\Sandbox\SecurityPolicyInterface;
+use Twig\Template;
+
+/**
+ * Represents a security policy which need to be enforced when sandbox mode is enabled.
+ *
+ * Modified by Jan Böhmer, to allow inheritance of methods and properties via class hierachy.
+ *
+ * @author Fabien Potencier <fabien@symfony.com>
+ */
+final class InheritanceSecurityPolicy implements SecurityPolicyInterface
+{
+    private $allowedTags;
+    private $allowedFilters;
+    private $allowedMethods;
+    private $allowedProperties;
+    private $allowedFunctions;
+
+    public function __construct(array $allowedTags = [], array $allowedFilters = [], array $allowedMethods = [], array $allowedProperties = [], array $allowedFunctions = [])
+    {
+        $this->allowedTags = $allowedTags;
+        $this->allowedFilters = $allowedFilters;
+        $this->setAllowedMethods($allowedMethods);
+        $this->allowedProperties = $allowedProperties;
+        $this->allowedFunctions = $allowedFunctions;
+    }
+
+    public function setAllowedTags(array $tags): void
+    {
+        $this->allowedTags = $tags;
+    }
+
+    public function setAllowedFilters(array $filters): void
+    {
+        $this->allowedFilters = $filters;
+    }
+
+    public function setAllowedMethods(array $methods): void
+    {
+        $this->allowedMethods = [];
+        foreach ($methods as $class => $m) {
+            $this->allowedMethods[$class] = array_map(function ($value) { return strtr($value, 'ABCDEFGHIJKLMNOPQRSTUVWXYZ', 'abcdefghijklmnopqrstuvwxyz'); }, \is_array($m) ? $m : [$m]);
+        }
+    }
+
+    public function setAllowedProperties(array $properties): void
+    {
+        $this->allowedProperties = $properties;
+    }
+
+    public function setAllowedFunctions(array $functions): void
+    {
+        $this->allowedFunctions = $functions;
+    }
+
+    public function checkSecurity($tags, $filters, $functions): void
+    {
+        foreach ($tags as $tag) {
+            if (!\in_array($tag, $this->allowedTags)) {
+                throw new SecurityNotAllowedTagError(sprintf('Tag "%s" is not allowed.', $tag), $tag);
+            }
+        }
+
+        foreach ($filters as $filter) {
+            if (!\in_array($filter, $this->allowedFilters)) {
+                throw new SecurityNotAllowedFilterError(sprintf('Filter "%s" is not allowed.', $filter), $filter);
+            }
+        }
+
+        foreach ($functions as $function) {
+            if (!\in_array($function, $this->allowedFunctions)) {
+                throw new SecurityNotAllowedFunctionError(sprintf('Function "%s" is not allowed.', $function), $function);
+            }
+        }
+    }
+
+    public function checkMethodAllowed($obj, $method): void
+    {
+        if ($obj instanceof Template || $obj instanceof Markup) {
+            return;
+        }
+
+        $allowed = false;
+        $method = strtr($method, 'ABCDEFGHIJKLMNOPQRSTUVWXYZ', 'abcdefghijklmnopqrstuvwxyz');
+        foreach ($this->allowedMethods as $class => $methods) {
+            if ($obj instanceof $class) {
+                $allowed = \in_array($method, $methods);
+
+                //CHANGED: Only break if we the method is allowed, otherwise try it on the other methods
+                if ($allowed) {
+                    break;
+                }
+            }
+        }
+
+        if (!$allowed) {
+            $class = \get_class($obj);
+            throw new SecurityNotAllowedMethodError(sprintf('Calling "%s" method on a "%s" object is not allowed.', $method, $class), $class, $method);
+        }
+    }
+
+    public function checkPropertyAllowed($obj, $property): void
+    {
+        $allowed = false;
+        foreach ($this->allowedProperties as $class => $properties) {
+            if ($obj instanceof $class) {
+                $allowed = \in_array($property, \is_array($properties) ? $properties : [$properties]);
+
+                //CHANGED: Only break if we the method is allowed, otherwise try it on the other methods
+                if ($allowed) {
+                    break;
+                }
+            }
+        }
+
+        if (!$allowed) {
+            $class = \get_class($obj);
+            throw new SecurityNotAllowedPropertyError(sprintf('Calling "%s" property on a "%s" object is not allowed.', $property, $class), $class, $property);
+        }
+    }
+}