public ActionResult Login(LoginModel model, string password, string returnUrl)
        {
            if (ModelState.IsValid)
            {
                if (_backend.ValidateUser(model.UserName, model.Password))
                {
                    FormsAuthentication.SetAuthCookie(model.UserName, false);
                    if (Url.IsLocalUrl(returnUrl))
                    {
                        return(Redirect(returnUrl));
                    }
                    else
                    {
                        return(RedirectToAction("Index", "Home"));
                    }
                }
                else
                {
                    ModelState.AddModelError("", "The user name or password provided is incorrect.");
                }
            }

            // If we got this far, something failed, redisplay form
            return(View(model));
        }