Sustainsys Saml2 Handler AuthenticateAsync() method operation is not implemented

Question

I'm trying a simple implementation in my Asp net Core application of Saml2 to integrate with an Ad FS server. I can't figure why I am getting this error. I downloaded the samples from the gitHub and tried to adapt it in my application.

NotImplementedException: The method or operation is not implemented.
Sustainsys.Saml2.AspNetCore2.Saml2Handler.AuthenticateAsync()

Here's my implementation, my application is running on Asp Net Core

On StartUp

                services
                    .AddAuthentication(sharedOptions =>
                    {
                        sharedOptions.DefaultSignInScheme = CookieAuthenticationDefaults.AuthenticationScheme;
                        sharedOptions.DefaultChallengeScheme = Saml2Defaults.Scheme;
                    })
                    .AddSaml2(options =>
                    {
                        options.SPOptions.EntityId = new EntityId("http://myAdfsServer.myDomain.com/adfs/services/trust");
                        options.SPOptions.ReturnUrl = new Uri("https://localhost:5000");
                        options.IdentityProviders.Add(
                            new IdentityProvider(new EntityId("http://myAdfsServer.myDomain.com/adfs/services/trust"), options.SPOptions)
                            {
                               LoadMetadata = true,
                               MetadataLocation = "https://myAdfsServer.myDomain.com/FederationMetadata/2007-06/FederationMetadata.xml"
                                //MetadataLocation = "FederationMetadata.xml"
                            });

                        //options.SPOptions.ServiceCertificates.Add(new X509Certificate2(certificate.ToString()));
                    })
                    .AddCookie();

On my Controller trying something similar to Sustainsys SAML2 Sample for ASP.NET Core WebAPI without Identity

    [Authorize(AuthenticationSchemes = Saml2Defaults.Scheme)]
    public class AuthenticationController : Controller
    {
        public AuthenticationController()
        {

        }

        [AllowAnonymous]
        public async Task LoginAdfs()
        {
            string redirectUri = string.Concat("https://localhost:5000", "/verifyAdfs");
            try
            {
                new ChallengeResult(
                    Saml2Defaults.Scheme,
                    new AuthenticationProperties
                    {
                        RedirectUri = Url.Action(nameof(LoginCallback), new { redirectUri })
                    });
            }catch(Exception e)
            {

            }
        }

        [AllowAnonymous]
        public async Task<IActionResult> LoginCallback(string returnUrl)
        {
            var authenticateResult = await HttpContext.AuthenticateAsync(Saml2Defaults.Scheme);

            //_log.Information("Authenticate result: {@authenticateResult}", authenticateResult);

            // I get false here and no information on claims etc.
            if (!authenticateResult.Succeeded)
            {
                return Unauthorized();
            }

            var claimsIdentity = new ClaimsIdentity("Email");
            claimsIdentity.AddClaim(authenticateResult.Principal.FindFirst(ClaimTypes.NameIdentifier));

           // _log.Information("Logged in user with following claims: {@Claims}", authenticateResult.Principal.Claims);

            await HttpContext.SignInAsync("Email", new ClaimsPrincipal(claimsIdentity));

            return LocalRedirect(returnUrl);
        }
}

note: I've got a client that won't expose his MetaData in a URL, so I'll need to adapt it and set manually the metadata parameters

I'm stuck in this error, I does not even hit my method LoginAdfs.

Answer 1

The Saml2 handler cannot be used as an authencation scheme, it is a challenge scheme.

I guess that the LoginAdfs() method works fine, but that it's the LoginCallback that fails. The reason should be the call to HttpContext.AuthenticationAsync(Saml2Defaults.Scheme).

You should instead authenticate with the cookie scheme - because that's what keeps the session. Internally when the challenge is completed, the Saml2 handler will use the DefaultSignInScheme to preserve the result in a session (through a cookie, as that's the default sign in scheme).