ASP MVC Authorize all actions except a few

Ok, this is what I did. If there is a better way let me know.

public class NotAuthorizeAttribute : FilterAttribute
{
    // Does nothing, just used for decoration
}

public class BaseController : Controller
{
    protected override void OnActionExecuting(ActionExecutingContext filterContext)
    {
        // Check if this action has NotAuthorizeAttribute
        object[] attributes = filterContext.ActionDescriptor.GetCustomAttributes(true);
        if (attributes.Any(a => a is NotAuthorizeAttribute)) return;

        // Must login
        if (!filterContext.HttpContext.User.Identity.IsAuthenticated)
        {
            filterContext.Result = new HttpUnauthorizedResult();
        }
    }
}