Classic ASP SAML Single Sign-On (SSO) with Microsoft 365 (Office) as IDP

Classic ASP SAML Single Sign-On (SSO) module gives the ability to enable SAML Single Sign-On for your Classic ASP applications. Using Single Sign-On you can use only one password to access your Classic ASP application and services. Our module is compatible with all the SAML compliant identity providers. Here we will go through a step-by-step guide to configure SAML Single Sign-On (SSO) between Classic ASP and Microsoft 365 (Office) considering Microsoft 365 (Office) as IdP.

Steps to configure Classic ASP SAML Single Sign-On (SSO) using Microsoft 365 (Office) as IDP

1. Setup Connector for application on IIS

• Extract the downloaded asp-net-saml-sso-connector zip file to get ASP.NET SAML 2.0 Connector.
• Add the connector as separate application on IIS
• To Add Application in IIS Manager, copy the extracted folder to the following path: C:\inetpub\wwwroot.
• Open IIS manager.In left panel right click on your site and click Add Application.

• Add Alias Name for your application. For example: ssoapp
• Give the Physical path where you have copied the Application: C:\inetpub\wwwroot\asp-net-saml-sso-connector-xxx.

2. Steps to give authority/permission to users to use SAML Connector

• Go to this path C:\inetpub\wwwroot\
• Right click the asp-net-saml-sso-connector-xxx and select Properties
• Select the Security tab and click the Edit button.
• Select IIS_IUSRS in under Group or Usernames option.
• Give Full Control permission for IIS_IUSRS container as shown in the figure below:

3. Open miniOrange SAML ASP.NET Connector on Browser

• Open any browser and go to the following link: https://<new-application-base-url>/.
• Login or Register to SAML connector in order to access the connector's admin dashboard.

4. Configure Microsoft 365 (Office) as IDP

• You need to provide SP Entity ID and ACS URL values while configuring your Identity Provider. Just copy and paste the SP Entity ID and ACS URL from connector to your IdP configuration page.You can refer to the image below.

• Go to https://portal.azure.com/ and login into Office365.
• Log into Office365 Admin Console.
• Click on Azure Active Directory

• Click on App Registration -> New Registrations

• Enter the Application Name and enter Redirect URI (ACS URL from ASP.NET SAML SSO module from Service Provider Metadata option) then Click on Register.

• Click on API Permissions -> Add Permission then select API as Office 365 Management APIs.

• Select the ActivityFeed.Read .

• Click on Overview -> Endpoints and copy the Federation metadata document URL. Keep the metadata url handy it will require later to configure step 3.

5. Configure ASP.NET SAML Connector as Service Provider

• After configuring your Identity Provider, it will provide you with IDP Entity ID, IDP Single Sign On URL and x.509 Certificate. Configure these values under IDP Entity ID, Single Sign-On Url and SAML X509 Certificate fields respectively.
• Click Save to Save your IDP details.

6. Testing SAML SSO

• Click on Test Configuration button to test whether the connector is configured correctly or not.
• The below Screenshot shows a successful result.

7. Attribute Mapping

• Attribute Mapping helps you to get attributes in your ASP.NET application received from your IdP and map them to your user attributes in application.
• Attributes received in successful test configuration are used for attribute mapping.
• You can refer to the below image for attribute mapping:

8. Integration Code

• miniOrange SSO connector will POST a signed JWT token on this endpoint which will contain the authenticated user's info. So, first create a POST endpoint in your application.
• Download the integration library (.dll file ) using the download option in the integration tab and add it to your project. This library contains the classes and methods with which you can verify the JWT token signature and also retrieve the user attributes from the token.
• Use string token, string public_key function to verify the token signature.It takes token (string) and public_key (string) as parameters and returns a bool value after verification.
• Once the verification returns true, then use getUserAttr(string token, string attr_name) function to retrieve user attributes from the token. It takes token (string) and attr_name (string) as parameters and returns attribute value (string) on success otherwise it returns an empty string.
• Add the namespace as "Miniorange.SSO.SAML.Integrate"
• You can refer to the example below for the integration part: Integrate intgtr= new Integrate(); // create instance for Integrate class
string public_key = "1wEaPr7h34Ts+DbgPytEqwkcJlybYwOTyBVD4GryebjSIF....................";
//Your public key displayed above.
string token = Request.Form["token"];
string username ="";
if (!String.IsNullOrEmpty(token)) {
// Verifying if the token is received from the trusted source.
if ( intgtr.Verify(token, public_key))
{ username = intgtr.getUserAttr(token, "userid"); // retrieve the attribute value using getUserAttr method }
} // using the received attributes from token you can create the session for that user.

9. Login Setup

• Provide the created endpoint URL for your ASP.NET application in Login Setup where you will read the JWT Token with the user attributes.
• Click on the Save button.

10. Add SSO Link

• Use the following URL as a link in your application from where you want to perform SSO:
  https://<application-base-url>/request.aspx
• For example you can use it as:
  <a href="https://<application-base-url>/request.aspx”>Log in</a>"

11. Add SLO Link

• Use the following URL as a link in your application from where you want to perform SLO:
  https://<application-base-url>/singlelogout.aspx
• For example you can use it as:
  <a href="https://<application-base-url>/singlelogout.aspx”>Logout</a>"

Additional Resources

• ASP.NET OAuth Single Sign-On (SSO)
• Web3 login for ASP.NET Applications
• DNN SAML Single Sign-On (SSO)
• DNN REST API Authentication
• nopCommerce SAML Single Sign-On (SSO)
• nopCommerce OAuth Single Sign-On (SSO)
• Umbraco SAML Single Sign-On (SSO)