FileExtensionSecureConstraintValidator.php

<?php

declare (strict_types=1);
namespace Drupal\file\Plugin\Validation\Constraint;

use Drupal\Core\Config\ConfigFactoryInterface;
use Drupal\Core\DependencyInjection\ContainerInjectionInterface;
use Drupal\Core\File\FileSystemInterface;
use Symfony\Component\DependencyInjection\ContainerInterface;
use Symfony\Component\Validator\Constraint;
use Symfony\Component\Validator\Exception\UnexpectedTypeException;

/**
 * Validator for the FileExtensionSecureConstraint.
 */
class FileExtensionSecureConstraintValidator extends BaseFileConstraintValidator implements ContainerInjectionInterface {
    
    /**
     * Creates a new FileExtensionSecureConstraintValidator.
     *
     * @param \Drupal\Core\Config\ConfigFactoryInterface $configFactory
     *   The config factory.
     */
    public function __construct(ConfigFactoryInterface $configFactory) {
    }
    
    /**
     * {@inheritdoc}
     */
    public static function create(ContainerInterface $container) {
        return new static($container->get('config.factory'));
    }
    
    /**
     * {@inheritdoc}
     */
    public function validate(mixed $value, Constraint $constraint) {
        $file = $this->assertValueIsFile($value);
        if (!$constraint instanceof FileExtensionSecureConstraint) {
            throw new UnexpectedTypeException($constraint, FileExtensionSecureConstraint::class);
        }
        $allowInsecureUploads = $this->configFactory
            ->get('system.file')
            ->get('allow_insecure_uploads');
        if (!$allowInsecureUploads && preg_match(FileSystemInterface::INSECURE_EXTENSION_REGEX, $file->getFilename())) {
            $this->context
                ->addViolation($constraint->message);
        }
    }

}