Tag Archives: duende

Implement a secure MCP server using OAuth DPoP and Duende identity provider

This post demonstrates how an ASP.NET Core application can connect to a secure MCP server using OpenID Connect and OAuth. Both applications use Duende IdentityServer as the identity provider. The MCP server requires delegated DPoP access tokens. Code: https://github.com/damienbod/McpOidcOAuth Setup The UI application authenticates with the Duende IdentityServer using OpenID Connect. Upon successful authentication, a […]

Use swiyu, the Swiss E-ID to authenticate users with Duende and .NET Aspire

This post shows how to authenticate users using Duende IdentityServer and ASP.NET Core Identity which verifies identities (verifiable digital credentials) using the Swiss Digital identity and trust infrastructure (swiyu). The swiyu infrastructure is implemented using the provided generic containers which implement the OpenID for Verifiable Presentations standards as well as many other standards for implementing […]

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 […]

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 […]

Authentication with multiple identity providers in ASP.NET Core

This article shows how to implement authentication in ASP.NET Core using multiple identity providers or secure token servers. When using multiple identity providers, the authentication flows need to be separated per scheme for the sign-in flow and the sign-out flow. The claims are different and would require mapping logic depending on the authorization logic of […]

Securing APIs using ASP.NET Core and OAuth 2.0 DPoP

This article shows how an ASP.NET Core application can access an ASP.NET Core API using OAuth Demonstrating Proof-of-Possession (DPoP). This is a really powerful security enhancement which is relatively easy to support. The access tokens should only be used for what the access tokens are intended for. OAuth DPoP helps force this. This solution was […]