Implement SSO in web application with different techs.

Question

I have two projects one is in ASP.NET that uses form authentication for the login. And the second is in simple javascript and HTML CSS. I want to implement SSO in these projects. Both are hosted on the same subdomain I do not want to use any third-party paid library.

Deepak Rawat · Answer

Set up a shared cookie or token-based authentication mechanism: In your ASP.NET project configure the authentication system to issue a secure authentication cookie upon successful login. This cookie should contain the necessary user information such as the user's identity or a token. When the user logs in to your ASP.NET project ensure that the authentication cookie is created with a domain that covers both projects (e.g. example.com or subdomain.example.com ). In your JavaScript/HTML/CSS project you need to handle the authentication process. One option is to send a request to the ASP.NET project's login endpoint passing the necessary credentials. If the login is successful store the authentication cookie returned by the ASP.NET project. Implement authentication verification in both projects: In your ASP.NET project create an endpoint or middleware that verifies the authenticity of the authentication cookie. This endpoint should be accessible by the JavaScript/HTML/CSS project. In your JavaScript/HTML/CSS project whenever a user accesses a page or performs an action that requires authentication send a request to the ASP.NET project's authentication verification endpoint with the stored authentication cookie. If the authentication cookie is valid the ASP.NET project should return a successful response. Ensure secure communication: To maintain security make sure that both projects are hosted on HTTPS to encrypt the communication and prevent cookie hijacking. When sending requests from the JavaScript/HTML/CSS project to the ASP.NET project use secure cross-origin communication techniques such as CORS (Cross-Origin Resource Sharing) to prevent unauthorized access. Implement SSO logout: When a user logs out from one project make sure to clear the authentication cookie and perform any necessary cleanup. You might need to handle the logout process separately in each project as the logout actions may vary depending on the authentication mechanisms used.