GetAppServiceIdentityAsync AAD returns null - azure-active-directory

I have a working Azure Mobile .NET backend which has a requirement to expose data securely through a TableController.
The table controller has the the [Authorize] attribute on the controller class definition and I have Token Store Enabled in the Azure Portal's Authentication / Authorization blade.
I'm using the following code to get the user's credentials passed by the mobile client app:
var creds = await this.User.GetAppServiceIdentityAsync(this.Request);
However, when deployed to the Azure portal this always returns a NULL exception; digging deeper I can see "Exception=System.ArgumentOutOfRangeException: The 'principal' parameter must be of type 'ClaimsPrincipal'."
Using JWT.IO, I've inspected the token being passed from the client app and the token looks 100% correct.
With the backend deployed to the Azure Portal and a breakpoint set I see that this.User is null!
How do I get access to the user's credentials, has anyone got this working?
Cheers,
Iain

Related

Two identical Azure apps with different access_token format - one JWT, the other non-JWT

When accessing /.auth/me, one app has the access_token in the correct JWT format, but in the other app it's not in JWT format.
This is the valid JWT one: eyJ0eXAiOiJKV1QiLCJu...eyJhdWQiOiJodHRwczov...B84ciSKwF2oOre5n
This is the non-JWT one: PAQABAAAAAAD--DLA3VO7QrddgJg7WevrTLy
The configuration for both apps appear to be identical.
Any idea how to fix the second app to also show JWT access token?
Usually when the authentication flow configuration has not included resource
as one of the parameter, the access token does not have form of a (
JSON Web Token)JWT token token format.
Please try to include resource with your application Id Uri or
resource that your application requires . To find the App ID URI, in
the Azure portal, click Azure Active Directory, click App
registrations, click the service application, and then click Settings
and Properties.
Also set the clientId and client secret in the request.
In other cases just to access the app service you could use id_token or Bearer as response_type in authorization header as Authorization:Bearer "{your-id-token}".
Reference:Oauth 2.0 grant credentials ,Access token request | Microsoft Docs
You can make use of azure resource explorer to edit the properties of the app service auth to include the resource if not already included. See resource provider and types
To get an access token, please try to set the resource using the Azure Resource Explorer.
Navigate to the Resource Explorer from the App Service.
Go to config > authsettings and click on Edit.
Update the additionalLoginParams with ["resource=<Name/ID of the resource>"] and click on PUT.
For example:
“additionalLoginParams”: [
“resource=https://graph.microsoft.com ”
]
Then by saving changes and refreshing the App Service, try again and check that the value for the access token is in the form of a JWT token or not.

Azure Active Directory - UI > API - 401 Error

Good Day,
Currently I have a single tenent with a React UI and .NET Core Apis secured by Azure Active Directory without any problems.
We have recently moved to a new Azure Tenent, new Active Directory etc. I have create two new App Registrations, one single App Service for UI and one for API. I have linked the App Service to AAD (UI = UI App Registration, API = API App Registration).
The problem is the API is getting a 401 error and I think see that in the original tenent the Bearer token is in a JWT format but in the new instance it's not, I believe it my be a graph api access key.
New Tenent:
Authorization: Bearer PAQABAAAAAAD--DLA3VO7QrddgJg7WevrQvEQVbZEMD8su-tIp9k2bTFUTort7SZgeDI52P6KRYefHgtmj4YrecgUKZJ2wylGuhvIzIz642n7Sg0VMU1RwKtrzWlaMqK62CaSoJcstxiEf6 *****
Orginal Tenent:
Bearer eyJ0eXAiOiJKV1QiLCJhbGciOiJSUzI1NiIsIng1dCI6Im5PbzNaRHJPRFhFSzFqS1doWHNsSFJfS1hFZyIsImtpZCI6Im5PbzNaRHJPRFhFSzFqS1doWHNsSFJfS1hFZyJ9.eyJhdWQiOiI3OThkN2ZkOC0zODk2LTQxOGMtOTQ0Ny0wNGFlNTQ2OGFkNDIiLCJpc3MiOiJodHRwczovL3N0cy53aW5kb3dzLm5ldC83ZDE3NTU3Ni03Y2Y3LTQyMDctOTA5My0wNmNiNmQyZDIwNjAvIiwiaWF0IjoxNjE2NDUyNzExLCJuYmYiOjE2MTY0NTI3MTEsImV4cCI6MTYxNjQ1NjYxMSwiYWNyIjoiMSIsImFpbyI6IkFTUUEyLzhUQUFBQU9mejhPZHp *****
Please someone kindly enought to provide some guidance / input where I am going wrong.
Regards
Paul.
When using Azure AD to obtain an access token, an additional resource parameter is required. Otherwise, the access token is not a JWT.
For example, if your web API's application ID URI is https://contoso.com/api and the scope name is Employees.Read.All, then with oidc-client the client configuration should be :
scope: 'openid profile email Employees.Read.All',
extraQueryParams: {
resource: 'https://contoso.com/api'
}
In App Service auth configuration, you can use additionalLoginParams
"additionalLoginParams": ["response_type=code", "resource=https://contoso.com/api"]
If you did not use a custom application ID URI, it may look like
api://868662dd-3e28-4c7f-b7d5-7ec02ac9c601
Quickstart: Configure an application to expose a web API
Firstly, the scope is incorrect.
You should Expose an API in your API App Registration and then add it as a permission in your UI App Registration. You can refer to this document.
And when you try to call the 'https://login.windows.net/{tenant}/oauth2/authorize endpoint, you need to specify the scope to include api://{app id of the API App Registration}. For example: api://{app id of the API App Registration} openid profile email. Then the access token would be for calling your API.
At last, for CORS issue, please configure the CORS as * in your web app to see if it helps.
Try to follow this step: Configure App Service to return a usable access token
In my experience, this problem occurs, when you try to authorize against version 1 of the endpoint.
Instead of calling
https://login.microsoftonline.com/{tenant}/oauth2/authorize
call
https://login.microsoftonline.com/{tenant}/oauth2/v2.0/authorize
You might be required to set something like "metadata URL" in you authorization library to:
https://login.microsoftonline.com/{tenant}/oauth2/v2.0/.well-known/openid-configuration
Make sure your builder follows this order...lifted from our API program.cs
These must be in order of
UseRouting -> UseAuthentication -> UseAuthorisation -> MapControllers
> app.UseRouting()
> app.UseAuthentication()
> app.UseAuthorization()
> app.MapControllers()
If app.UseAuthentication and app.UseAuthorization are not in this order in statement position you Will get 401 Unauthorised as at 01/2023 .Net 6 Core.

How to get user info with a valid Bearer Token?

At work we are making an SPFx Web Part React client app that deploys to SharePoint as a Web Part. Our back-end is a ASP.NET Core 2.2 Web API that is secured using Azure Portal's built in Authentication feature. The front-end is using AadHttpClient that magically handles the authentication by taking the context of the current page (SharePoint) that has the user already logged in. Doing so, silent authentication occurs and the API call is successfully made with authentication successfully passed. The AadHttpClient is supposed to magically bundle up the token in the request header that gets sent to the back-end Web API. I still need to debug the live development app and see how to retrieve the Bearer Token in the back-end Web API. These are my next probable steps?
Would I just probably use 'string bearerToken = Request.Headers.....;' or 'string bearerToken = Request.Headers["KeyValue"]' to get the token itself?
Assuming I can get this Bearer Token, how can I check the caller's user information? Is it just var userName = User.Identity.Name;? Or would I or could I use the token and some how make a call to Microsoft Graph API to view the user's info?
If you are using ASP.NET Core and using default authentication then things are bit easier. From documentation you can see that several tokens are injected in the request header based on Identity provider so in your case you have to look for following headers which Azure AD injects. These headers would contain ID Token which you would need to verify the claims and get user information.
X-MS-TOKEN-AAD-ID-TOKEN
X-MS-TOKEN-AAD-ACCESS-TOKEN
X-MS-TOKEN-AAD-EXPIRES-ON
X-MS-TOKEN-AAD-REFRESH-TOKEN
Ideally all the claims are injected automatically in ClaimsPrincipal
you can find more here
Official Docs
How To extract Token

Swaggerbuckle with AAD --Error AADSTS500013: Resource identifier is not provided

I'm trying to use AzureAD to get a token in swagger and test my .netCore2.1 API with it.(using Swashbuckle.AspNetCore 4.0.1)
To do this I completed the following steps
1. Created a Web API project(asp.net Core2.1)
2. Register an Azure AD (AAD) app for the Web API
3. Updated the Web API project to use Azure AD authentication
4. Register an AAD app for the Swagger web site https://localhost:5001/swagger
5. Granted permissions for the Swagger AAD app to access the Web API AAD app
6. Generated a Client Secret for the Swagger AAD app
7. Enabled OAuth2 implicit flow on the Swagger AAD app
8. Added Swagger to the Web API project
When I authenticate, I am getting the following error.
Error AADSTS500013: Resource identifier is not provided .
When I click authorize
I am getting error AADSTS500013: Resource identifier is not provided.
My WebAPI project's startup.cs file goes here
Please help me understand which resource Identifier I am missing here or how to resolve this error.
Or any pointers on how to use Swaggerbuckle with ASP.NET Core webAPI, especially with AAD authenticated WebAPI ?
UPDATES
I copied my webAPI's APPID URI from azure portal. ie Dashboard>>Microsoft - App registrations>>MY_API_APP>>Settings>>Properties>>App ID URI
But I am still getting the same error when I try to authenticate
Error AADSTS500013: Resource identifier is not provided
Usually resource identifier which uniquely identifies your application. You can easily found your resource Identifier Like below:
When logged into the Azure portal, Azure Active Directory > App Registrations > [App Name] > Settings> Properties, then it's the App ID URI
See the screen shot:
In the orignal OAuth 2.0 specification, there is no resource parameter in the authorization request. It use scope parameter. The authorization and token endpoints allow the client to specify the scope of the access request using the "scope" request parameter.
As document explains, when Azure AD implement the OAuth 2.0(1.0 endpoint), the resource is used to specify the access_token you request for which resource. And the Azure AD will issue the token which the scp based on the permission you config on the portal for the resource.
And in the v2.0 endpoint, the Azure AD also use the scope to support the dynamic permission request. More detail you can have a look here.
Usual Reason for Error
Make sure you have configured below steps accordingly.
Like below:
Application Manifest
Reply URI
Request Endpoint
For V1.0 refer this URI https://login.microsoft.com//oauth2/authorize
For V2.0 refer this URI https://login.microsoft.com//oauth2/v2.0/authorize
Application Consent
Need to confirm your application required resource access permission you could refer here
I believe this step can lead you to sort out your problem.
With Azure AD V1.0 app you need set resource to identify which api you want to access during the authentication&access token requests :
Code flow :
https://learn.microsoft.com/en-us/azure/active-directory/develop/v1-protocols-oauth-code
Implicit flow :
https://learn.microsoft.com/en-us/azure/active-directory/develop/v1-oauth2-implicit-grant-flow
In Swashbuckle.AspNetCore 4.0.1 , you need to config the resource as parameter if you want to get access token for accessing your web api :
app.UseSwaggerUI(options =>
{
options.SwaggerEndpoint("/swagger/v1/swagger.json", "MySite API V1");
options.OAuthClientId("19c73866-562f-482a-bafb-89d9fe9b0aaa");
options.OAuthAppName("Swagger Api Calls");
// add resource
options.OAuthAdditionalQueryStringParams(new Dictionary<string, string>() { { "resource", "f479db30-9b62-431b-98c2-bcaae52203cf" } });
});
For us Nan Yu's response got us one step closer.
We added the resource in the AdditionalQuerystringParams like so:
options.OAuthAdditionalQueryStringParams(new Dictionary<string, string>() { { "resource", "{ResourceIDHere}" } });
We are now able to get passed the Auth step in Swagger, but trying routes out doesn't seem to pass the token to the api called and so we get a 401 Error.
change { "scope", API_AppID_URI} to { "resource", API_AppID_URI}

How does AAD API Access delegate permission work?

I'm having a little trouble following how API Access delegate permissions work with azure active directory. I feel like i'm probably misunderstanding a key aspect of how AAD works.
Here is my set up
I have a Web Application let’s call it WebApp. I have created
an AAD for the Web Application and registered with a AAD App ID. Let’s
call it App ID A
I have a Web Api let’s call it ApiService. I have also created an AAD for it and registered with a AAD App ID. Let’s all it App ID B.
In AAD App ID A, I have updated the clicked on the API Access ->
Required Permissions -> Add (App ID B ; Web API) permissions
I’ve updated the manaifest in the AAD App ID B, to give consent to
knownClientApplications to include the client ID of the Web App
I’ve also enable oauth2AllowImplicitFlow to be true for both App’s
manifest.
What I’m trying to do is, A user signs into the web application sign. When it signs in, the user is able to acquire a token for the specific Web App App ID A. The user should be able to use that token and have access the Api Service with App ID B. I thought by configuring the whole API Access -> Required Permissions within the Web Application it would give me delegate permission with the logged in user to communicate with the Api Service WebApi.
When I examine the JWT token, I notice that there is a claim for Microsoft Graph, but not for the ApiService. Shouldn’t I be seeing a claim?
When I try to use the token, it reacts with a 404 authentication error.
Any advice appreciated,
Thanks,
Derek
UPDATE
In response to #joonasw
I actually looked at the example you wrote when i started.
https://joonasw.net/view/aspnet-core-2-azure-ad-authentication
In the example, the web application is initialized with:
.AddOpenIdConnect(opts =>
{
Configuration.GetSection("OpenIdConnect").Bind(opts);
opts.Events = new OpenIdConnectEvents
{
OnAuthorizationCodeReceived = ctx =>
{
return Task.CompletedTask;
}
};
});
In the HomeController, there is code to retrieve the token for the graph api
private async Task<string> GetAccessTokenAsync()
{
string authority = _authOptions.Authority;
string userId = User.FindFirstValue("http://schemas.microsoft.com/identity/claims/objectidentifier");
var cache = new AdalDistributedTokenCache(_cache, _dataProtectionProvider, userId);
var authContext = new AuthenticationContext(authority, cache);
//App's credentials may be needed if access tokens need to be refreshed with a refresh token
string clientId = _authOptions.ClientId;
string clientSecret = _authOptions.ClientSecret;
var credential = new ClientCredential(clientId, clientSecret);
var result = await authContext.AcquireTokenSilentAsync(
"https://graph.microsoft.com",
credential,
new UserIdentifier(userId, UserIdentifierType.UniqueId));
return result.AccessToken;
}
From my understanding, when the user initially login to the web application it will trigger the OnAuthorizationCodeReceived() method where it will be using the clientId/clientSecret/resource of the web applicaiton. The token is stored in the distributed token cache under the key resource/client id.
In the example, GetAccessTokenAsync() is used to grab the token to access the graph API.
In my case, I was hoping to update that method to retrieve the token for the WebApi which has a different clientId/clientSecret/resoruce. In my case, it will AcquireTokenSilentAsync will throw an AdalTokenAcquisitionExceptionFilter because the token needed is not stored in the cache and in the AdalTokenAcquisitionExceptionFilter it will call try to reauthenticate
context.Result = new ChallengeResult();
which will redirect to the authentication page and then hits the AddOpenIdConnect() method. However, the openIdConnect is configured with the web app clientID/ClientSecret/Resource and will not store the new token properly. It will try to call GetAccessTokenAsync() again and the whole process will go in an infinite loop.
In the example, if you were to comment out the "Anthentication:resource" in app.settings, you will experience the same issue with the infinite loop. What happens is that you initially authenticate correctly with no resource specified. Then when you click on you try to get the token for microsoft graph which is a new resource, it can't find it in the cache and then tries to reauthenticate over and over again.
I also notice that the acquireAsyncAuthentication only returns a AuthenticationResult with a bearer tokentype. How would you get the refresh token in this case?
Any advice?
Thanks,
Derek
UPDATE (Solution)
Thanks to #jaanus. All you have to do is update the resource to the clientid of the web api and pass that into AcquireTokenSilentAsync. The web api id uri that you can get from the azure portal did not work.
Okay, so it seems there are multiple questions here. I'll try to make some sense of this stuff to you.
Adding the "Web App"'s client id to the "ApiService" knownClientApplications is a good idea.
It allows for consent to be done for both apps at the same time. This really only matters for multi-tenant scenarios though.
Now, your Web App will be acquiring access tokens at some point.
When it does, it must specify a resource parameter.
This parameter says to AAD which API you wish to call.
In the case of the "ApiService", you should use either its client id or Application ID URI (this is more common).
Depending on the type of your Web App, the access token is acquired a bit differently.
For "traditional" back-end apps, the Authorization Code Grant flow is usually used.
In this flow your back-end gets an authorization code after the user logs in, and your Web App can then exchange that code for the access token.
In the case of a front-end JavaScript app, you would use the Implicit Grant flow, which you have allowed (no need to enable it in the API by the way).
This one allows you to get access tokens directly from the authorization endpoint (/oauth2/authorize) without talking to the token endpoint as you usually have to.
You can actually get the access token right away after login in the fragment of the URL if you wish.
ADAL.JS makes this quite a lot easier for you if you are going in this route.
The reason you get the authentication error is because the access token is probably meant for Microsoft Graph API. You need to request an access token for your API.
An access token is always only valid for one API.

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