- How to register an AAD application
- How to create an Open ID Connect request to authenticate an user
- How to receive an ID token in a Fragment URL for receiving information about the authenticated user
This is very similar to challenge 0, except that this time we will receive the id_token
through a fragment URL instead of it being in the body.
Before you can authenticate an user you have to register an application in your AAD tenant. You can either use the PowerShell Module Az or Azure CLI.
New-AzADApplication -DisplayName ChallengeIdTokenFragment -IdentifierUris https://challengeidtokenfragment -ReplyUrls http://localhost:5001/api/tokenechofragment
Retrieve and note the ID of your current AAD tenant via:
Get-AzContext
az ad app create --display-name challengeidtokenfragment --reply-urls http://localhost:5001/api/tokenechofragment --identifier-uris https://challengeidtokenfragment
Retrieve and note the ID of your current AAD tenant via:
az account show
Open another shell and run the Token Echo Server from apps/token-echo-server
in this repository. This helper ASP.NET Core tool is used to echo the token issued by your AAD. The tool is listening on port 5001 on your local machine. Tokens are accepted on the route http://localhost:5001/api/tokenechofragment
. This is why we initially registered an AAD application with a reply url pointing to http://localhost:5001/api/tokenechofragment
.
dotnet run
Replace TENANT_ID
with your TenantId and APPLICATION_ID
with your ApplicationId. Open a browser and paste the modified request.
https://login.microsoftonline.com/TENANT_ID/oauth2/v2.0/authorize?
client_id=APPLICATION_ID
&response_type=id_token
&redirect_uri=http%3A%2F%2Flocalhost%3A5001%2Fapi%2Ftokenechofragment
&response_mode=fragment
&scope=openid%20profile
&nonce=1234
Copy the id_token
value from your browser's address bar, go to https://jwt.ms and paste the token. Take a minute and have a look at the decoded token.
If you need further information about the issued claims take a look here.
Remove-AzAdApplication -ApplicationId <applicationid> -Force
az ad app delete --id <applicationid>
This challenge showed how to create a new application in AAD and how user can be authenticated using the Open ID Connect protocol. The full process is described here.