Understanding ADB2C Custom Policies

Oct 13, 2025 by magicalceylontours.com 124 views

Introduction

In this article, we will explore the process of adding query parameters in Azure Active Directory B2C (ADB2C) to ADB2C federated authentication using the OpenID Connect (OIDC) protocol. This is a crucial step in implementing a seamless authentication experience for users across different ADB2C tenants. We will delve into the details of configuring ADB2C custom policies to achieve this goal.

Prerequisites

Before we begin, ensure that you have the following:

An Azure Active Directory B2C (ADB2C) tenant
Familiarity with Azure AD B2C custom policies
Knowledge of OpenID Connect (OIDC) protocol
Access to the Azure portal

Understanding ADB2C Custom Policies

ADB2C custom policies are a powerful tool for customizing the authentication experience in Azure Active Directory B2C. These policies allow you to define the behavior of the authentication flow, including the addition of query parameters. In this section, we will explore the basics of ADB2C custom policies and how to create a new policy.

Creating a New Custom Policy

To create a new custom policy, follow these steps:

Log in to the Azure portal and navigate to your ADB2C tenant.
Click on Policies and then click on New policy.
Select Custom policy as the policy type.
Enter a name for your policy and click on Create.

Understanding OIDC Protocol

OpenID Connect (OIDC) is an authentication protocol that allows clients to verify the identity of users. In the context of ADB2C federated authentication, OIDC is used to authenticate users across different ADB2C tenants. In this section, we will explore the basics of OIDC protocol and how it is used in ADB2C federated authentication.

OIDC Flow

The OIDC flow involves the following steps:

The client (in this case, the ADB2C tenant) initiates an authentication request to the authorization server (the other ADB2C tenant).
The authorization server redirects the user to the login page.
The user enters their credentials and submits the form.
The authorization server verifies the user's credentials and redirects them back to the client with an authorization code.
The client exchanges the authorization code for an access token, which can be used to authenticate the user.

Adding Query Parameters to OIDC Flow

To add query parameters to the OIDC flow, you need to modify the custom policy to include the required parameters. In this section, we will explore how to add query parameters to the OIDC flow using ADB2C custom policies.

Modifying the Custom Policy

To modify the custom policy, follow these steps:

Open the custom policy you created earlier.
Click on the Claims tab and then click on Add claim.
Select Query parameter as the claim type.
Enter the name of the query parameter and its value.
Click on Add to add the claim to the policy.

Configuring the OIDC Flow

To configure the OIDC flow, follow these steps:

Open the custom policy you created earlier.
Click on the OIDC tab and then click on Add OIDC configuration.
Select the OIDC provider (the other ADB2C tenant).
Enter the client ID and client secret for the OIDC provider.
Click on Add to add the OIDC configuration to the policy.

Testing the OIDC Flow

To test the OIDC flow, follow these steps:

Log in to the Azure portal and navigate to your ADB2C tenant.
Click on Policies and then click on the custom policy you created earlier.
Click on Test to test the OIDC flow.

Troubleshooting

If you encounter any issues during the OIDC flow, follow these steps to troubleshoot:

Check the custom policy for any errors or warnings.
Verify that the OIDC provider is correctly configured.
Check the query parameters for any errors or warnings.

Conclusion

In this article, we explored the process of adding query parameters in ADB2C to ADB2C federated authentication using the OIDC protocol. We delved into the details of configuring ADB2C custom policies to achieve this goal. By following the steps outlined in this article, you should be able to successfully add query parameters to the OIDC flow and implement a seamless authentication experience for users across different ADB2C tenants.

Best Practices

Always test the OIDC flow before deploying it to production.
Verify that the OIDC provider is correctly configured.
Check the query parameters for any errors or warnings.
Use ADB2C custom policies to customize the authentication experience.
Use OIDC protocol to authenticate users across different ADB2C tenants.

FAQs

Q: What is OIDC protocol? A: OIDC is an authentication protocol that allows clients to verify the identity of users.
Q: How do I add query parameters to the OIDC flow? A: You need to modify the custom policy to include the required parameters.
Q: What is the OIDC flow? A: The OIDC flow involves the client initiating an authentication request to the authorization server, the user entering their credentials, and the authorization server verifying the user's credentials and redirecting them back to the client with an authorization code.