Tag Archives: OAuth2

Securing multiple Auth0 APIs in ASP.NET Core using OAuth Bearer tokens

This article shows a strategy for security multiple APIs which have different authorization requirements but the tokens are issued by the same authority. Auth0 is used as the identity provider. A user API and a service API are implemented in the ASP.NET Core API project. The access token for the user API data is created […]

Securing Blazor Web assembly using Cookies and Auth0

The article shows how an ASP.NET Core Blazor web assembly UI hosted in an ASP.NET Core application can be secured using cookies. Auth0 is used as the identity provider. The trusted application is protected using the Open ID Connect code flow with a secret and using PKCE. The API calls are protected using the secure […]

Secure Azure AD User File Upload with Azure AD Storage and ASP.NET Core

This post shows how files can be uploaded to Azure blob storage using ASP.NET Core in a secure way using OAuth and Open ID Connect. Azure AD is used to authenticate the users. The uploaded file descriptions are saved to an SQL database using EF Core so that listing or searching files can be implemented […]

Implement app roles authorization with Azure AD and ASP.NET Core

This post shows how to implement Azure AD App roles and applied to users or groups in Azure AD. The roles are used in an ASP.NET Core Razor page application as well as a ASP.NET Core API. The roles from the access token and the id token are used to authorize the identity which is […]

Implement OAUTH Device Code Flow with Azure AD and ASP.NET Core

The post shows how the Device Code flow (RFC 8628) could be implemented in an ASP.NET Core web application which uses Azure AD as an identity provider. An Azure App registration is used to setup the client. This solution would be useful for input constrained devices which have a browser and need to authenticate identities. […]

Protecting legacy APIs with an ASP.NET Core Yarp reverse proxy and Azure AD OAuth

This article shows how a legacy API could be protected using an ASP.NET Core Yarp reverse proxy and Azure AD OAuth. The security is implemented using Azure AD and Microsoft.Identity.Web. Sometimes it is not possible to update an existing or old API within a reasonable price and the financially best way to use it in […]

Using multiple APIs in Angular and ASP.NET Core with Azure AD authentication

This article shows how an Angular application could be used to access many APIs in a secure way. An API is created specifically for the Angular UI and the further APIs can only be access from the trusted backend which is under our control. Code: https://github.com/damienbod/AzureADAuthRazorUiServiceApiCertificate Posts in this series Implement Azure AD Client credentials […]

Securing an ASP.NET Core API which uses multiple access tokens

This post shows how an ASP.NET Core API can authorize API calls which use different access tokens from different identity providers or different access tokens from the same identity provider but created for different clients and containing different claims. The access tokens are validated using JWT Bearer authentication as well as an authorization policy which […]

Implement a Web APP and an ASP.NET Core Secure API using Azure AD which delegates to a second API

This article shows how an ASP.NET Core Web application can authenticate and access a downstream API using user access tokens and delegate to another API in Azure AD also using user access tokens. Microsoft.Identity.Web is used in all three applications to acquire the tokens for the Web API and the access tokens for the two […]

Implement Azure AD Client credentials flow using Client Certificates for service APIs

This post shows how to implement an Azure client credential flows to access an API for a service-to-service connection. No user is involved in this flow. A client certificate (Private Key JWT authentication) is used to get the access token and the token is used to access the API which is then used and validated […]