public ActionResult Login(Users model)
        {
            if (ModelState.IsValid)
            {
                Users user = psc.Check(model);

                if (user == null)
                {
                    ModelState.AddModelError("", "Неверный логин или пароль.");
                }
                else
                {
                    ClaimsIdentity claim = new ClaimsIdentity("ApplicationCookie", ClaimsIdentity.DefaultNameClaimType, ClaimsIdentity.DefaultRoleClaimType);
                    claim.AddClaim(new Claim(ClaimTypes.NameIdentifier, user.Id.ToString(), ClaimValueTypes.String));
                    claim.AddClaim(new Claim(ClaimsIdentity.DefaultNameClaimType, user.Login, ClaimValueTypes.String));
                    claim.AddClaim(new Claim("http://schemas.microsoft.com/accesscontrolservice/2010/07/claims/identityprovider",
                                             "OWIN Provider", ClaimValueTypes.String));

                    AuthenticationManager.SignOut();
                    AuthenticationManager.SignIn(new AuthenticationProperties {
                        IsPersistent = true
                    }, claim);
                    return(RedirectToAction("Index", "Admin"));
                }
            }
            return(View(model));
        }