Tag Archives: OAuth2
Implement a secure MCP OAuth desktop client using OAuth and Entra ID
The article demonstrates how to implement a secure MCP OAuth desktop client using Microsoft Entra ID. The MCP server is built with ASP.NET Core and secured using Microsoft Entra ID. The MCP client is a .NET console application that must acquire an OAuth access token to interact with the MCP server. Code: https://github.com/damienbod/McpSecurity Setup A […]
Implement a secure MCP server using OAuth and Entra ID
The article shows how to implement a secure model context protocol (MCP) server using OAuth and Entra ID. The MCP server is implemented using ASP.NET Core and uses Microsoft Entra ID to secure the API. An ASP.NET Core application using Azure OpenAI and semantic kernel is used to implement the MCP client for the agent […]
Use EdDSA signatures to validate tokens in ASP.NET Core using OpenID Connect
Some identity providers use the EdDSA / ED25519 algorithm to sign and issue tokens. This post shows how to validate the tokens using the Nuget package from ScottBrady and ASP.NET Core. Using the default OpenID Connect setup, the keys are not read and the tokens cannot be validated. The error message could return something like […]
Implement ASP.NET Core OpenID Connect with Keycloak to implement Level of Authentication (LoA) requirements
This post looks at implementing an OpenID Connect client in ASP.NET Core and require a level of authentication (LoA) implemented using Keycloak. The applications are hosted using Aspire. The LoA is requested in Keycloak using the acr_values claim. Code: https://github.com/damienbod/IdentityExternalErrorHandling Setup The applications are implemented using Aspire. An ASP.NET Core application uses an OpenID Connect […]
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 […]
Using multiple external identity providers from ASP.NET Core Identity and Duende IdentityServer
This blog post shows how an ASP.NET Core Identity application can integrate and implement multiple external identity providers. An OIDC client UI uses the solution and is implemented using Duende IdentityServer. The same scheme is used for all the external providers and mapped to the identity for the client UI and the application. Using OpenID […]
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 […]
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