I'm developing a Blazor WASM hosted application and have some questions on how to properly secure it.
The idea is that users will authenticate using an external identity provider (OpenIDConnect/PKCE), however I do not have access to the identity provider to change it's configuration. The app is able to authenticate users with the Microsoft.AspNetCore.Components.WebAssembly.Authentication library, but I'm unable to secure my API.
Since I cannot change the IP's configuration to include access to my API in the access token, what options do I have? Do i have to use IdentityServer? Can I use this (https://identityserver4.readthedocs.io/en/latest/topics/signin_external_providers.html) even though the external IP the app is using is not listed among the external providers (Google etc.) How can I secure my API?
Thanks in advance!