API method to register new user in identityserver3 - asp.net

I have an API proxy that do the rest of my business login, identityserver for authorization and Android Client.
I using implicit flow with the android client.
I request an access token from idsrv then make a request including this token to contact with the api and every things works correctly.
Now i want an API or any way to register new user instead of the default web page so i can use this APIs to create new users from my proxy or from my android app.
What is the better way to do that?

This is, by design, out of the scope of IdentityServer. You can build your own API that can update the user database for user provisioning.

Related

Feed Azure OAuth access / refresh token to MSAL backend for caching

I've got a mobile app that uses a native oauth flow via react-native-oauth (which makes use of an inAppBrowser) to complete the oath flow for ios. When it's complete, I have the tokens and idToken natively.
What I'd like to do now is to pass these to my backend web server, so that I can kick start some calendar sync process for this user. However, my backend is using MSAL.NET with a custom TokenCache, so expects the tokens to be present in this cache. To achieve this on the web app, there is an oauth flow baked into the web app that is hooked into this MSAL setup, and thus works:
// Hook the auth code up to the token cache, that will ensure it gets into the database (msal_token_cache)
TokenCache cache = new MsaldbTokenCache(userId, db).GetMsalCacheInstance();
ConfidentialClientApplication cca = new ConfidentialClientApplication(opts.ClientId,
settings.Core.BaseUrl.UrlCombine(redirectUrl),
new ClientCredential(opts.ClientSecret),
cache,
null);
AuthenticationResult result =
await cca.AcquireTokenByAuthorizationCodeAsync(code, new[] {"Calendars.ReadWrite"});
I've no idea how to do this with my ios-authed tokens. I can't allow the web server to acquire the tokens via auth code exchange since it was initiated in IOS...
Can anyone help?
I would design the solution to be architecturally separated so that it supports both web and mobile, which should work fine as long as both clients use the correct scopes for OAuth redirects:
A Rest API triggers the calendar sync process for the user received in the access token
One client of the Rest API is the back end of a web app - which uses MSAL.Net - and perhaps issues cookies to the browser
Another client of the Rest API is the mobile app - which uses React Native OAuth
I would avoid aiming to mix the 2 clients together though. If the web back end requires auth cookies then the mobile client will not be able to provide them.
The back end for the mobile app needs to a Rest API endpoint and it's possible that the existing back end may need to be refactored a little, to separate web client concerns from API concerns.

IdentityServer4 Web Login via id_token or access_token

Context
I'm building a hybrid native/web app. Part of it will be API driven, and part of it will be webviews showing an existing website.
Once logged in with my OIDC SDK (Amplify/AppAuth), I can access the user's id_token and access_token.
However, because the webviews used in the SDK are not controllable, I cannot reuse the cookies generated by my identity server.
Question
For the reason above, I'm trying to login a user from their id_token or their access_token. (both are JWTs)
I believe this isn't supported by IdentityServer4, but I am looking to implement something myself.
What I have found so far:
1) id_token_hint
OpenID Connect Core 1.0, Section 3.1.2.1, id_token_hint parameter:
OPTIONAL. ID Token previously issued by the Authorization Server being passed as a hint about the End-User's current or past authenticated session with the Client. If the End-User identified by the ID Token is logged in or is logged in by the request, then the Authorization Server returns a positive response; otherwise, it SHOULD return an error, such as login_required. When possible, an id_token_hint SHOULD be present when prompt=none is used and an invalid_request error MAY be returned if it is not; however, the server SHOULD respond successfully when possible, even if it is not present. The Authorization Server need not be listed as an audience of the ID Token when it is used as an id_token_hint value.
If the ID Token received by the RP from the OP is encrypted, to use it as an id_token_hint, the Client MUST decrypt the signed ID Token contained within the encrypted ID Token. The Client MAY re-encrypt the signed ID token to the Authentication Server using a key that enables the server to decrypt the ID Token, and use the re-encrypted ID token as the id_token_hint value.
According to this optional spec of OpenID, I should be able to use the id_token on the /authorize endpoint to login the user. I know this isn't implemented in IdentityServer4, but I'm looking at AddCustomAuthorizeRequestValidator to do that. However I'm not sure how to "get a user from their id_token" in the code. Do you have any pointers?
2) using AddJwtBearerClientAuthentication
This method sounds like I could authenticate from my access_token, but I can't find much documentation on how to use it.
THE PROBLEM
Let me know if I am misunderstanding requirements, but it feels like you have 2 different apps and are trying to make them feel like a single integrated set of screens.
The default behaviour will be as follows since web views are private browser sessions and cannot use system browser cookies. You want to prevent the second step since it is a poor user experience:
User signs in to the mobile app
Whenever a secured web view is invoked, there is a new private browser session with no auth cookie, therefore requiring a new login
COMMON APPROACH: SUPPLY A TOKEN TO THE WEB VIEW
It can be common to forward the mobile token to the web view, if the two apps are part of the same user experience. If required, extend the mobile app's scopes to include those for the web app.
You should not need to issue any new tokens or change the security model of either app. But the mobile and web apps need to work together on a solution.
POSSIBLE WEB VIEW SOLUTION FOR A SERVER SIDE WEB APP
This might be the simplest option:
Provide new .Net Core web back end entry point URLs that require tokens instead of cookies
The mobile app could then call those endpoints from web views, and supply its own token in the Authorization Header of the web view request
The web back end could then forward mobile web view requests to your Web APIs
The code to add the Authorization Header to a web view request may be a little tricky but there are ways to do it:
Android
iOS
POSSIBLE WEB VIEW SOLUTION FOR AN SPA
An option that works for Cookieless SPAs is for the web view to ask the mobile host app for an access token via a Javascript bridge. Some code of mine does this for a cookieless SPA:
Web UI Code to Call the Mobile Host
Android Code
iOS Code
You can clone / run the mobile github repos from your local PC to see the solution. I will be writing up some notes on this in my blog's Mobile Web Integration Post.

Proper OAuth2 authentication flow for a web API using the EWS Managed API

I've been reading through a bunch of documentation for using OAuth with Azure AD, but am still completely confused about how to properly implement things for my situation. Hopefully someone can steer me in the right direction.
I have created an ASP.NET Web API application that uses the EWS Managed API to access Exchange on behalf of different users. My application exposes endpoints such as /Mailbox/Messages and /Appointments with the intent that some front end web application will eventually use them to retrieve a user's emails and appointments. Currently the endpoints are working using basic http authentication, but I'd like to update them to use OAuth. The application has been registered in my Azure AD instance and I've configured it to require the "Access mailboxes as the signed-in user via Exchange Web Services" API permission.
Since the front end hasn't been implemented yet, I've been trying to test by manually calling the authentication endpoint. This prompts me to log in and provide consent. If I consent, I'm redirected to the callback URL that I provided when I registered the app with the authorization code contained in the query parameters. I'm still not quite sure how I'm supposed to be using this callback, but for the sake of testing I currently have the callback redeem the authorization code for an access token. This is done by calling the AcquireTokenByAuthorizationCode method on an instance of the AuthenticationContext class and providing my application's id and secret. Again, just for the sake of testing I return the access token to the browser. I can then call my aforementioned endpoints (after some modifications) with this access token and get the emails for the user. I'm guessing much of this is not the correct way to be doing things.
Some of my points of confusion:
What should the callback that I registered in Azure AD actually be doing when it gets the authorization code? Is this intended for a different type of application? Perhaps one that isn't just playing the role of a middle man.
I'm trying to make my application somewhat RESTful, so I don't want to have to maintain the access tokens on my end between requests. As such, does it make sense for my endpoints to expect that the access token be provided in the authentication header for each request? If so, does that mean the front end application should be responsible acquiring the access token and passing it to me?
Being completely new to OAuth and Azure, I'm not sure if any other details are pertinent, but I can provide more information as needed.
What you are implementing is this scenario: https://learn.microsoft.com/en-us/azure/active-directory/active-directory-authentication-scenarios#daemon-or-server-application-to-web-api
Here's how it works:
Your client app redirects the user to sign in at the authorization endpoint
Your client app gets back an authorization code (if using the auth code grant flow, there are others)
The client app exchanges the code for an access token for your API app
It will need to provide its client id and secret along with the code and the API's resource URI to get it
The client app calls to your API app, passing the access token in the Authorization header
Your API app then validates the access token, and requests for another access token from Azure AD for the Exchange API
It will pass the access token sent by the client app, along with its client id and secret and the Exchange API's resource URI to Azure AD
Your API app receives an access token so you can call to the Exchange API as the user
And to answer your two questions:
Authorization code flow is not used with APIs, only with apps that have a user signing in, thus the redirect URL is basically never used
Your API can and must expect and authenticate the access token for it to be in every request. But the access token it uses to call the Exchange API can and should be cached on the API's side. This is provided out-of-the-box with ADAL, though the tokens are only in memory.

Challenge while setting up seamless authentication across MVC and Web API Layer

I work on an application where I have a separate MVC layer and Web API Layer, both have the same authentication mechanism, I have chosen the individual accounts authentication option while adding the projects. The web api service layer will be directly accessed by some other mobile clients also.
But when the user logs in through MVC he should be able to access Web Api seamlessly, but I don’t want to really pass the username and password from MVC to the Web Api layer, I am told it is a bad practice. but i need to authenticate and authorize my user, so the only option i have thought of is to have a default account at Web API level to issue tokens, and this will be called from MVC post the authentication and a token will be returned which is written to a cookie in the client. Now the Ajax calls from the UI can use this bearer token and get the job done.
The only glitch I have here is that, because I am using a default account I need user details again for authorization at service level, though I am doing authorization at my UI level, the user can spoof the system. I was lost here and came up with a solution like, when the user logs in to MVC will send across user details also along with the call to get the WebAPI token and issue another token to the user so that the user uses both of the tokens to make a call to web api from MVC.
I am not sure if this works or if it is even the best way. I just wanted to check, how I should go from here. Any help on this will be really great.
This is a really good example of integration - I know they use Angular as the client but you can learn from this:
http://bitoftech.net/2014/06/01/token-based-authentication-asp-net-web-api-2-owin-asp-net-identity/
Check this section to see how they decouple the API from the front end (Part of the same article).
http://bitoftech.net/2014/09/24/decouple-owin-authorization-server-resource-server-oauth-2-0-web-api/

Mobile app Web API authentication

I'm building a mobile application (that might also later become a web application). The server side is a ASP.NET MVC + Web API application and I'm thinking about ways how I could implement the service's user management and authentication.
How should I implement the registration/login screen in the app? Offer native app forms, that will send just API requests to the service or is it preferable to show a web browser component and display the website's login page and then extract a token after the user logs in? I see the first option is more user friendly, but the second one will let me change the login / registration page (like for example adding external authentication providers) without breaking older versions of the app.
My second question is regarding the external authentication providers. ASP.NET Identity has good support for them and it is quite possible to let users register using Facebook or some other OAuth2 provider. Does it make sense to add support for external authentication providers when I plan to expose the app's API publicly? Are there any reasons why that is not a good idea?
Your first option is best if you believe your users will trust you to manage their passwords. You make a secure call to your service, have the service produce a bearer token as the result. That would be an anonymous call. I used the answer from this question to get me going down that path:
Get IPrincipal from OAuth Bearer Token in OWIN
If your users are less likely to trust you with their credentials, then the web view and external provider is a good alternative. You would need to work with providers that support the "Implicit Grant Flow" since don't want to share the apps clientid and client secret on the mobile device. This approach involves using a web view to login in, and then capturing the token on the client uri fragment on the response. I think it is on a location header, but don't have a working example in front of me. Something like:
https://your.domain.com/#access_token = 8473987927394723943294
you would pass that token with each api call afterwards .
Good luck!

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