Two factor auth with IdentityServer3 - remember browser - identityserver3

Question

I'm implementing 2fa with IdentityServer3 + Asp.Net Identity (2.2.1). I'm stuck on the 2fa implementation. I've looked at the "AspNetIdentity_2fa" sample, which helped a lot.
I have everything wired up, except for the cookie that indicates the browser has been successfully authenticated. I can set the cookie during the code confirmation, but I cannot get to the cookie in the PostAuthenticateLocalAsync() call to see whether or not to take the 2fa path.
protected override Task<AuthenticateResult> PostAuthenticateLocalAsync(User user, SignInMessage message)
{
if (user.TwoFactorEnabled) // && !TwoFactorCookieSet...
{
return Task.FromResult(new AuthenticateResult("/auth/sendcode", user.Id, user.DisplayName));
}
return base.PostAuthenticateLocalAsync(user, message);
}
I believe I'm taking the correct approach in using the partial logins, but how would I detect that the current browser has already been approved?
More detail: the /auth/sendcode is the standard Asp.Net Identity pages/flow for 2fa, combined with the partial login logic from the sample.

Answer 1

Okay, I found that OwinEnvironmentService can be injected into IdentityServer services. I can get the cookies via OwinEnvironmentService. I'd be interested to hear any opinions on this solution (this isn't meant to be production-ready, it's just a concept):
internal class UserService : AspNetIdentityUserService<User, string>
{
private readonly OwinEnvironmentService _owinEnvironmentService;
public UserService(UserManager userMgr, OwinEnvironmentService owinEnvironmentService) : base(userMgr)
{
_owinEnvironmentService = owinEnvironmentService;
DisplayNameClaimType = IdentityServer3.Core.Constants.ClaimTypes.Name;
}
protected override Task<AuthenticateResult> PostAuthenticateLocalAsync(User user, SignInMessage message)
{
if (user.TwoFactorEnabled)
{
var twoFactorNeeded = false;
object httpContext;
if (_owinEnvironmentService.Environment.TryGetValue("System.Web.HttpContextBase", out httpContext))
{
var cookies = (httpContext as HttpContext)?.Request.Cookies;
if (cookies != null && !cookies.AllKeys.Contains(IdentityConstants.CookieNames.TwoFactorCompleted)) twoFactorNeeded = true;
}
if (twoFactorNeeded)
return Task.FromResult(new AuthenticateResult("/auth/sendcode", user.Id, user.DisplayName));
}
return base.PostAuthenticateLocalAsync(user, message);
}
}
UPDATED
Based on Brock's comment, I think I have a better solution.
// custom User Service
internal class UserService : AspNetIdentityUserService<User, string>
{
private readonly OwinEnvironmentService _owinEnvironmentService;
public UserService(UserManager userMgr, OwinEnvironmentService owinEnvironmentService) : base(userMgr)
{
_owinEnvironmentService = owinEnvironmentService;
DisplayNameClaimType = IdentityServer3.Core.Constants.ClaimTypes.Name;
}
protected override async Task<AuthenticateResult> PostAuthenticateLocalAsync(User user, SignInMessage message)
{
if (user.TwoFactorEnabled)
{
var owinContext = new OwinContext(_owinEnvironmentService.Environment);
var result = await owinContext.Authentication.AuthenticateAsync(DefaultAuthenticationTypes.TwoFactorRememberBrowserCookie);
if(result == null) return new AuthenticateResult("/auth/sendcode", user.Id, user.DisplayName);
}
return await base.PostAuthenticateLocalAsync(user, message);
}
}
// (in MVC controller) generate the 2FA security code and send it
public async Task<ActionResult> SendCode(SendCodeViewModel model)
{
// ...some code removed for brevity...
var token = await UserManager.GenerateTwoFactorTokenAsync(userId, model.SelectedProvider);
var identityResult = await UserManager.NotifyTwoFactorTokenAsync(userId, model.SelectedProvider, token);
if (!identityResult.Succeeded) return View("Error");
return RedirectToAction("VerifyCode", new { Provider = model.SelectedProvider, model.ReturnUrl, model.RememberMe });
}
// (in MVC controller) verify the code and sign in with 2FA
public async Task<ActionResult> VerifyCode(VerifyCodeViewModel model)
{
// ...some code removed for brevity...
var signInManager = new SignInManager<User, string>(UserManager, Request.GetOwinContext().Authentication);
if (await UserManager.VerifyTwoFactorTokenAsync(user.Id, model.Provider, model.Code))
{
await UserManager.ResetAccessFailedCountAsync(user.Id);
await signInManager.SignInAsync(user, model.RememberMe, model.RememberBrowser);
var resumeUrl = await env.GetPartialLoginResumeUrlAsync();
return Redirect(resumeUrl);
}
else
{
await UserManager.AccessFailedAsync(user.Id);
ModelState.AddModelError("", "Invalid code.");
return View(model);
}
}

Answer 2

I implemented the same for remember browser requirement however following statement return always null when we logout and login again.so twofactory step is not skipped..
var result = await owinContext.Authentication.AuthenticateAsync(DefaultAuthenticationTypes.TwoFactorRememberBrowserCookie);