How to use Windows Active Directory Authentication and Identity Based Claims?

Question

Problem

We want to use Windows Active Directory to authenticate a user into the application. However, we do not want to use Active Directory groups to manage authorization of controllers/views.

As far as I know, there is not an easy way to marry AD and identity based claims.

Goals

• Authenticate users with local Active Directory
• Use Identity framework to manage claims

Attempts (Fails)

• Windows.Owin.Security.ActiveDirectory - Doh. This is for Azure AD. No LDAP support. Could they have called it AzureActiveDirectory instead?
• Windows Authentication - This is okay with NTLM or Keberos authentication. The problems start with: i) tokens and claims are all managed by AD and I can't figure out how to use identity claims with it.
• LDAP - But these seems to be forcing me to manually do forms authentication in order to use identity claims? Surely there must be an easier way?

Any help would be more than appreciated. I have been stuck on this problem quite a long time and would appreciate outside input on the matter.

Answer 1

Shoe your solution above pushed me toward a direction that worked for me on MVC6-Beta3 Identityframework7-Beta3 EntityFramework7-Beta3:

// POST: /Account/Login
[HttpPost]
[AllowAnonymous]
[ValidateAntiForgeryToken]
public async Task<IActionResult> Login(LoginViewModel model, string returnUrl = null)
{
    if (!ModelState.IsValid)
    {
        return View(model);
    }

    //
    // Check for user existance in Identity Framework
    //
    ApplicationUser applicationUser = await _userManager.FindByNameAsync(model.eID);
    if (applicationUser == null)
    {
        ModelState.AddModelError("", "Invalid username");
        return View(model);
    }

    //
    // Authenticate user credentials against Active Directory
    //
    bool isAuthenticated = await Authentication.ValidateCredentialsAsync(
        _applicationSettings.Options.DomainController, 
        _applicationSettings.Options.DomainControllerSslPort, 
        model.eID, model.Password);
    if (isAuthenticated == false)
    {
        ModelState.AddModelError("", "Invalid username or password.");
        return View(model);
    }

    //
    // Signing the user step 1.
    //
    IdentityResult identityResult 
        = await _userManager.CreateAsync(
            applicationUser, 
            cancellationToken: Context.RequestAborted);

    if(identityResult != IdentityResult.Success)
    {
        foreach (IdentityError error in identityResult.Errors)
        {
            ModelState.AddModelError("", error.Description);
        }
        return View(model);
    }

    //
    // Signing the user step 2.
    //
    await _signInManager.SignInAsync(applicationUser,
        isPersistent: false,
        authenticationMethod:null,
        cancellationToken: Context.RequestAborted);

    return RedirectToLocal(returnUrl);
}

Answer 2

Just hit AD with the username and password instead of authenticating against your DB

// POST: /Account/Login
[HttpPost]
[AllowAnonymous]
[ValidateAntiForgeryToken]
public async Task<ActionResult> Login(LoginViewModel model, string returnUrl)
{
    if (ModelState.IsValid)
    {
        var user = await UserManager.FindByNameAsync(model.UserName);
        if (user != null && AuthenticateAD(model.UserName, model.Password))
        {
            await SignInAsync(user, model.RememberMe);
            return RedirectToLocal(returnUrl);
        }
        else
        {
            ModelState.AddModelError("", "Invalid username or password.");
        }
    }
    return View(model);
}

public bool AuthenticateAD(string username, string password)
{
    using(var context = new PrincipalContext(ContextType.Domain, "MYDOMAIN"))
    {
        return context.ValidateCredentials(username, password);
    }
}

Answer 3

On ASPNET5 (beta6), the idea is to use CookieAuthentication and Identity : you'll need to add in your Startup class :

public void ConfigureServices(IServiceCollection services)
{
    services.AddMvc();
    services.AddAuthorization();
    services.AddIdentity<MyUser, MyRole>()
        .AddUserStore<MyUserStore<MyUser>>()
        .AddRoleStore<MyRoleStore<MyRole>>()
        .AddUserManager<MyUserManager>()
        .AddDefaultTokenProviders();
}

In the configure section, add:

private void ConfigureAuth(IApplicationBuilder app)
{
    // Use Microsoft.AspNet.Identity & Cookie authentication
    app.UseIdentity();
    app.UseCookieAuthentication(options =>
    {
        options.AutomaticAuthentication = true;
        options.LoginPath = new PathString("/App/Login");
    });
}

Then, you will need to implement:

Microsoft.AspNet.Identity.IUserStore
Microsoft.AspNet.Identity.IRoleStore
Microsoft.AspNet.Identity.IUserClaimsPrincipalFactory

and extend/override:

Microsoft.AspNet.Identity.UserManager
Microsoft.AspNet.Identity.SignInManager

I actually have setup a sample project to show how this can be done. GitHub Link.

I tested on the beta8 and and with some small adaptatons (like Context => HttpContext) it worked too.

Answer 4

You could use ClaimTransformation, I just got it working this afternoon using the article and code below. I am accessing an application with Window Authentication and then adding claims based on permissions stored in a SQL Database. This is a good article that should help you.

https://github.com/aspnet/Security/issues/863

In summary ...

services.AddScoped<IClaimsTransformer, ClaimsTransformer>();

app.UseClaimsTransformation(async (context) =>
{
IClaimsTransformer transformer = context.Context.RequestServices.GetRequiredService<IClaimsTransformer>();
return await transformer.TransformAsync(context);
});

public class ClaimsTransformer : IClaimsTransformer
    {
        private readonly DbContext _context;

        public ClaimsTransformer(DbContext dbContext)
        {
            _context = dbContext;
        }
        public async Task<ClaimsPrincipal> TransformAsync(ClaimsTransformationContext context)
        {

            System.Security.Principal.WindowsIdentity windowsIdentity = null;

            foreach (var i in context.Principal.Identities)
            {
                //windows token
                if (i.GetType() == typeof(System.Security.Principal.WindowsIdentity))
                {
                    windowsIdentity = (System.Security.Principal.WindowsIdentity)i;
                }
            }

            if (windowsIdentity != null)
            {
                //find user in database by username
                var username = windowsIdentity.Name.Remove(0, 6);
                var appUser = _context.User.FirstOrDefault(m => m.Username == username);

                if (appUser != null)
                {

                    ((ClaimsIdentity)context.Principal.Identity).AddClaim(new Claim("Id", Convert.ToString(appUser.Id)));

                    /*//add all claims from security profile
                    foreach (var p in appUser.Id)
                    {
                        ((ClaimsIdentity)context.Principal.Identity).AddClaim(new Claim(p.Permission, "true"));
                    }*/

                }

            }
            return await System.Threading.Tasks.Task.FromResult(context.Principal);
        }
    }

Answer 5

Do you know how to implement a custom System.Web.Security.MembershipProvider? You should be able to use this (override ValidateUser) in conjunction with System.DirectoryServices.AccountManagement.PrincipalContext.ValidateCredentials() to authenticate against active directory.

try: var pc = new PrincipalContext(ContextType.Domain, "example.com", "DC=example,DC=com"); pc.ValidateCredentials(username, password);