protected virtual async Task <IEnumerable <Claim> > GetClaimsForAuthenticateResult(TUser user) { List <Claim> claims = new List <Claim>(); if (EnableSecurityStamp && userManager.SupportsUserSecurityStamp) { var stamp = await userManager.GetSecurityStampAsync(user.Id); if (!String.IsNullOrWhiteSpace(stamp)) { claims.Add(new Claim("security_stamp", stamp)); } } return(claims); }