c# - What does https://<myapp>.azurewebsites.net/.auth/login/aad/callback mean?

Question

I am configuring Authentication for my Web application using Azure App Service. I chose AAD with Express mode to register my application.

It registered my application at AAD with reply-url as https://.azurewebsites.net/.auth/login/aad/callback. I intercepted the requests GET POST for above callback. It sends the access token.

Question: I have not implemented the controller for above reply-url in web application. Who is handling it correctly?

Please shed me some light on above callback. Can it be changed to different POST Url if needed?

Answer 1

The /.auth/login/{provider}/callback endpoint is exposed by Azure’s own Easy Auth [1].

There’s one for each of the identity providers in [1].

In short, they are responsible for extracting access token etc from the provider, setting cookies and so on. They are handled prior to the request landing in your app.

[1] https://docs.microsoft.com/en-us/azure/app-service/overview-authentication-authorization