MVC Core 2.0 and ASP.NET Forms Based Authentication

Question

My website is an online portal to data managed with a desktop (Silverlight) application. This application uses ASP.NET Forms Based Authentication to login a user.

The MVC Core 1.1 version of my website used MembershipProvider.ValidateUser from the System.Web.Security namespace to do this. Since I cannot add System.Web.dll to my ASP.NET MVC 2.0 project, how can I perform this validation?

If I am mistaken about adding System.Web.dll , please inform me, but I've looked into it and could not find the solution.

The Login method in my MVC Core 1.1 Controller:

[HttpPost]
[AllowAnonymous]
public IActionResult Login(LoginViewModel vmLogin)
{
    string loginName = $"{vmLogin.CompanyCode}\\{vmLogin.UserName}";

    MembershipProvider provider = Membership.Provider;
    if (provider.ValidateUser(loginName, vmLogin.Password))
    {
        Claim[] claims = { new Claim(ClaimTypes.Name, loginName) };
        ClaimsIdentity identity = new ClaimsIdentity(claims, "Custom");
        ClaimsPrincipal principal = new ClaimsPrincipal(identity);
        HttpContext.Authentication.SignInAsync("FundraiserCookieMiddlewareInstance", principal);

        return RedirectToAction("Index");
    }
    else
    {
        vmLogin.Password = string.Empty;
        vmLogin.Error = "Invalid Credentials";
        return View(vmLogin);
    }
}

The Models created from the database used for logging in:

Answer 1

ASP.NET Core 2.0 has a new identity model that is not backward compatible with the System.Web.Security namespace. The new identity provider models are here in GitHub and it contains a sample for ASP.NET MVC that is similar to your code. The following is a snippet of the Login method from the their AccountController sample code

// POST: /Account/Login
[HttpPost]
[AllowAnonymous]
[ValidateAntiForgeryToken]
public async Task<IActionResult> Login(LoginViewModel model, string returnUrl = null)
{
    ViewData["ReturnUrl"] = returnUrl;
    if (ModelState.IsValid)
    {
        // This doesn't count login failures towards account lockout
        // To enable password failures to trigger account lockout, set lockoutOnFailure: true
        var result = await _signInManager.PasswordSignInAsync(model.Email, model.Password, model.RememberMe, lockoutOnFailure: false);
        if (result.Succeeded)
        {
            _logger.LogInformation(1, "User logged in.");
            return RedirectToLocal(returnUrl);
        }
        if (result.RequiresTwoFactor)
        {
            return RedirectToAction(nameof(SendCode), new { ReturnUrl = returnUrl, RememberMe = model.RememberMe });
        }
        if (result.IsLockedOut)
        {
            _logger.LogWarning(2, "User account locked out.");
            return View("Lockout");
        }
        else
        {
            ModelState.AddModelError(string.Empty, "Invalid login attempt.");
            return View(model);
        }
    }

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