How to close the Open Redirect vulnerability?

Question

ASP.NET

How to close the Open Redirect vulnerability on a website written with ASP.NET?
Is it possible to create a list with "white" redirect addresses? If so, how?

Answer 1

private ActionResult RedirectToLocal(string returnUrl)
{
    if (Url.IsLocalUrl(returnUrl))
    {
        return Redirect(returnUrl);
    }
    else
    {
        return RedirectToAction("Index", "Home");
    }
}

In Asp.net core we use LocalRedirect.