Openiddict guidance related to external login - asp.net-web-api

Question

I have a mobile app that talks to a backend web API (core 2.0). Presently I have the API configured to use Opendidict with Facebook integration based on the configuration listed below.
public static IServiceCollection AddAuthentication(this IServiceCollection services, AppSettings settings)
{
services.AddOpenIddict<int>(options =>
{
options.AddEntityFrameworkCoreStores<RouteManagerContext>();
options.AddMvcBinders();
options.EnableAuthorizationEndpoint("/auth/authorize");
options.EnableTokenEndpoint("/auth/token");
options.AllowAuthorizationCodeFlow();
options.AllowImplicitFlow();
options.AllowPasswordFlow();
options.AllowRefreshTokenFlow();
options.SetAccessTokenLifetime(TimeSpan.FromMinutes(1));
options.SetRefreshTokenLifetime(TimeSpan.FromMinutes(20160));
options.DisableHttpsRequirement();
options.AddEphemeralSigningKey();
});
services.AddAuthentication()
.AddFacebook(o => { o.ClientId = settings.FacebookAppID; o.ClientSecret = settings.FacebookAppSecret; })
.AddOAuthValidation();
return services;
}
The password flow works perfectly when they want to use local account. What I'm struggling with is how to return the access/refresh token after successfully authenticating with Facebook. I have the standard account controller with ExternalLogin and ExternalLoginCallback which also works perfectly as I'm able to successfully login and get the local user account it's tied to and signed in.
In my mind, the user clicks facebook login, which calls ExternalLogincallBack, which logs in the user. After that all I want to do is return the access/refresh token just like the password flow.
When I try to use the ImplicitFlow by providing the implicit flow arguments in the redirect (/auth/authorize?...) from ExternalLoginCallback, I can get the access token, but no refresh token even if I specify the offline_scope. From what I read, it seems the implicit flow doesn't support refresh so I tried code flow.
When using the CodeFlow, I can get the code token from the redirect to "/auth/authorize" but can't figure out how to call into the token endpoint from the authorize endpoint to return the access/refresh token directly to the client app. Do I just need to return the code to the client and have them make another call to post to the token endpoint to get access/refresh tokens?
This doesn't feel correct and I'm stumped. Seems like I should be able to just return the access/refresh token after I've signed in externally just like what happens with password flow. Any help would be greatly appreciated as I've been struggling with this for several days.
[HttpGet("~/auth/authorize")]
public async Task<IActionResult> Authorize(OpenIdConnectRequest request)
{
if (!User.Identity.IsAuthenticated)
{
// If the client application request promptless authentication,
// return an error indicating that the user is not logged in.
if (request.HasPrompt(OpenIdConnectConstants.Prompts.None))
{
var properties = new AuthenticationProperties(new Dictionary<string, string>
{
[OpenIdConnectConstants.Properties.Error] = OpenIdConnectConstants.Errors.LoginRequired,
[OpenIdConnectConstants.Properties.ErrorDescription] = "The user is not logged in."
});
// Ask OpenIddict to return a login_required error to the client application.
return Forbid(properties, OpenIdConnectServerDefaults.AuthenticationScheme);
}
return Challenge();
}
// Retrieve the profile of the logged in user.
var user = await _userManager.GetUserAsync(User);
if (user == null)
{
return BadRequest(new
{
Error = OpenIdConnectConstants.Errors.ServerError,
ErrorDescription = "An internal error has occurred"
});
}
// Create a new authentication ticket.
var ticket = await CreateTicketAsync(request, user);
// Returning a SignInResult will ask OpenIddict to issue the appropriate access/identity tokens.
return SignIn(ticket.Principal, ticket.Properties, ticket.AuthenticationScheme);
}
private async Task<AuthenticationTicket> CreateTicketAsync(OpenIdConnectRequest request, ApplicationUser user, AuthenticationProperties properties = null)
{
// Create a new ClaimsPrincipal containing the claims that will be used to create an id_token, a token or a code.
var principal = await _signInManager.CreateUserPrincipalAsync(user);
// Create a new authentication ticket holding the user identity.
var ticket = new AuthenticationTicket(principal, properties, OpenIdConnectServerDefaults.AuthenticationScheme);
if (!request.IsRefreshTokenGrantType())
{
// Set the list of scopes granted to the client application.
// Note: the offline_access scope must be granted to allow OpenIddict to return a refresh token.
ticket.SetScopes(new[]
{
OpenIdConnectConstants.Scopes.OpenId,
OpenIdConnectConstants.Scopes.Email,
OpenIdConnectConstants.Scopes.Profile,
OpenIdConnectConstants.Scopes.OfflineAccess,
OpenIddictConstants.Scopes.Roles
}.Intersect(request.GetScopes()));
}
ticket.SetResources("RouteManagerAPI");
// Note: by default, claims are NOT automatically included in the access and identity tokens.
// To allow OpenIddict to serialize them, you must attach them to a destination, that specifies
// whether they should be included in access tokens, in identity tokens or in both.
foreach (var claim in ticket.Principal.Claims)
{
// Never include the security stamp in the access and identity tokens, as it's a secret value.
if (claim.Type == _identityOptions.Value.ClaimsIdentity.SecurityStampClaimType)
{
continue;
}
var destinations = new List<string>
{
OpenIdConnectConstants.Destinations.AccessToken
};
// Only add the iterated claim to the id_token if the corresponding scope was granted to the client application.
// The other claims will only be added to the access_token, which is encrypted when using the default format.
if ((claim.Type == OpenIdConnectConstants.Claims.Name && ticket.HasScope(OpenIdConnectConstants.Scopes.Profile)) ||
(claim.Type == OpenIdConnectConstants.Claims.Email && ticket.HasScope(OpenIdConnectConstants.Scopes.Email)) ||
(claim.Type == OpenIdConnectConstants.Claims.Role && ticket.HasScope(OpenIddictConstants.Claims.Roles)))
{
destinations.Add(OpenIdConnectConstants.Destinations.IdentityToken);
}
claim.SetDestinations(destinations);
}
return ticket;
}

Answer 1

When I try to use the CodeFlow, I can get the code token but can't figure out how to call into the token endpoint from the authorize endpoint to return the access/refresh token directly to the client app. Do I just need to return the code to the client and have them make another call to post to the token endpoint to get access/refresh tokens?
That's exactly what you're supposed to do as the code flow is a 2-part process: once your mobile apps has an authorization code, it must redeem it using a simple HTTP call to the token endpoint to get an access token and a refresh token.