<?php
/*
* This file is part of the Symfony package.
*
* (c) Fabien Potencier <fabien@symfony.com>
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
namespace Symfony\Component\Security\Core\Authorization\Voter;
use Symfony\Component\ExpressionLanguage\Expression;
use Symfony\Component\HttpFoundation\Request;
use Symfony\Component\Security\Core\Authentication\AuthenticationTrustResolverInterface;
use Symfony\Component\Security\Core\Authentication\Token\TokenInterface;
use Symfony\Component\Security\Core\Authorization\AuthorizationCheckerInterface;
use Symfony\Component\Security\Core\Authorization\ExpressionLanguage;
use Symfony\Component\Security\Core\Role\RoleHierarchyInterface;
/**
* ExpressionVoter votes based on the evaluation of an expression.
*
* @author Fabien Potencier <fabien@symfony.com>
*/
class ExpressionVoter implements CacheableVoterInterface
{
private ExpressionLanguage $expressionLanguage;
private AuthenticationTrustResolverInterface $trustResolver;
private AuthorizationCheckerInterface $authChecker;
private ?RoleHierarchyInterface $roleHierarchy;
public function __construct(ExpressionLanguage $expressionLanguage, AuthenticationTrustResolverInterface $trustResolver, AuthorizationCheckerInterface $authChecker, RoleHierarchyInterface $roleHierarchy = null)
{
$this->expressionLanguage = $expressionLanguage;
$this->trustResolver = $trustResolver;
$this->authChecker = $authChecker;
$this->roleHierarchy = $roleHierarchy;
}
public function supportsAttribute(string $attribute): bool
{
return false;
}
public function supportsType(string $subjectType): bool
{
return true;
}
public function vote(TokenInterface $token, mixed $subject, array $attributes): int
{
$result = VoterInterface::ACCESS_ABSTAIN;
$variables = null;
foreach ($attributes as $attribute) {
if (!$attribute instanceof Expression) {
continue;
}
$variables ??= $this->getVariables($token, $subject);
$result = VoterInterface::ACCESS_DENIED;
if ($this->expressionLanguage->evaluate($attribute, $variables)) {
return VoterInterface::ACCESS_GRANTED;
}
}
return $result;
}
private function getVariables(TokenInterface $token, mixed $subject): array
{
$roleNames = $token->getRoleNames();
if (null !== $this->roleHierarchy) {
$roleNames = $this->roleHierarchy->getReachableRoleNames($roleNames);
}
$variables = [
'token' => $token,
'user' => $token->getUser(),
'object' => $subject,
'subject' => $subject,
'role_names' => $roleNames,
'trust_resolver' => $this->trustResolver,
'auth_checker' => $this->authChecker,
];
// this is mainly to propose a better experience when the expression is used
// in an access control rule, as the developer does not know that it's going
// to be handled by this voter
if ($subject instanceof Request) {
$variables['request'] = $subject;
}
return $variables;
}
}