PermissionAccessCheck.php

<?php

namespace Drupal\user\Access;

use Drupal\Core\Access\AccessResult;
use Drupal\Core\Routing\Access\AccessInterface;
use Drupal\Core\Session\AccountInterface;
use Symfony\Component\Routing\Route;

/**
 * Determines access to routes based on permissions defined via
 * $module.permissions.yml files.
 */
class PermissionAccessCheck implements AccessInterface {
    
    /**
     * Checks access.
     *
     * @param \Symfony\Component\Routing\Route $route
     *   The route to check against.
     * @param \Drupal\Core\Session\AccountInterface $account
     *   The currently logged in account.
     *
     * @return \Drupal\Core\Access\AccessResultInterface
     *   The access result.
     */
    public function access(Route $route, AccountInterface $account) {
        $permission = $route->getRequirement('_permission');
        if ($permission === NULL) {
            return AccessResult::neutral();
        }
        // Allow to conjunct the permissions with OR ('+') or AND (',').
        $split = explode(',', $permission);
        if (count($split) > 1) {
            return AccessResult::allowedIfHasPermissions($account, $split, 'AND');
        }
        else {
            $split = explode('+', $permission);
            return AccessResult::allowedIfHasPermissions($account, $split, 'OR');
        }
    }

}