Category OAuth2
Experimental alternative flow for OAuth First-Party Applications
This post looks at an alternative way of implementing a native app authentication and authorization. At present, a web browser is used to implement authentication of native applications when using OAuth and OpenID Connect. The alternative approach implemented in the post is based on the OAuth 2.0 for First-Party Applications draft and adapted to be […]
Handling OpenID Connect error events in ASP.NET Core
ASP.NET Core provides great extension points for handling OpenID Connect error events. This blog looks at implementing error handling in an ASP.NET Core application implemented using ASP.NET Core Identity. Code: https://github.com/damienbod/IdentityExternalErrorHandling Setup The application uses OpenID Connect to implement the authentication of the user identities. This implements a standard OpenID Connect flow and uses Microsoft […]
Implement client assertions with client credentials flow using OAuth DPoP
This blog looks at implementing client assertions for the client credentials flow using OAuth 2.0 Demonstration of Proof-of-Possession (DPoP). The client credentials flow is an OAuth 2.0 authorization grant type used for machine-to-machine authentication. DPoP further strengthens the security by ensuring that the client possesses a specific key at the time of the request, forcing […]
Implement client assertions for OAuth client credential flows in ASP.NET Core
This blog implements client assertions using an OAuth client credential flow in ASP.NET Core. Client assertions provide a secure way for client authentication without sharing a secret, enhancing the security the OAuth client credentials flow. By using JSON Web Tokens (JWTs) client assertions, this approach ensures strong client identity (application) verification and mitigates risks associated […]
ASP.NET Core delegated Microsoft OBO access token management (Entra only)
This blog shows how to implement a delegated Microsoft On-Behalf-Of flow in ASP.NET Core, and has a focus on access token management. The solution uses Microsoft.Identity.Web to implement the different flows and it really simple to implement, when you know how to use the Nuget package and use the correct Microsoft documentation. The application can […]
Use client assertions in OpenID Connect and ASP.NET Core
Client assertions is a method of client authentication which can be used in OpenID Connect. This provides an alternative to client secrets. This approach enhances security by using signed tokens (JWTs) to authenticate clients during the token request process or the OAuth PAR request. In ASP.NET Core, client assertions is not supported per default, a […]
Customizing a single client sign-in using parameters in Duende IdentityServer
This post looks at customizing the sign-in UI and the sign-in options in an ASP.NET Core application using Duende IdentityServer and ASP.NET Core Identity. There are multiple ways of changing the look and feel of the UI for different OpenID Connect clients or different client flows. In the previous post, the UI was customized per […]
ASP.NET Core delegated OAuth Token Exchange access token management
This blog shows how to implement a delegated OAuth 2.0 Token Exchange RFC 8693 flow in ASP.NET Core, and has a focus on access token management. It looks at how the OAuth Token Exchange can be implemented and how an application can request delegated access tokens on behalf of a user and another application, providing […]
ASP.NET Core user application access token management
This article looks at management application access tokens in an ASP.NET Core web application. Any application with or without a user can use application access tokens as long as the application can persist the tokens in a safe way. Code: https://github.com/damienbod/token-mgmt-ui-application Blogs in this series Setup The ASP.NET Core web application authenticates using OpenID Connect […]
Using Entra External ID with an Auth0 OpenID Connect identity provider
This post looks at implementing an Open ID Connect identity provider in Microsoft Entra External ID. Auth0 is used as the identity provider and an ASP.NET Core application is used to test the authentication. Microsoft Entra External ID federates to Auth0. Client code: https://github.com/damienbod/EntraExternalIdCiam Microsoft Entra External ID supports federation using OpenID Connect and was […]
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