JASPIC (Java Authentication Service Provider Interface for Containers) is a Java EE security feature that allows developers to plug in custom authentication mechanisms into a web container. This provides flexibility in handling authentication and enables the use of third-party authentication providers.

In this article, we will discuss how to configure JASPIC in a web container, specifically in a Java EE application server like Apache Tomcat or WildFly.

1. Understanding JASPIC

JASPIC works based on the concepts of ServerAuthModule and MessageInfo. A ServerAuthModule is responsible for performing the actual authentication and can be implemented as per the specific authentication mechanism. The MessageInfo object contains information about the current request and response, which can be used by the ServerAuthModule to perform the authentication.

2. Implementing the ServerAuthModule

To configure JASPIC, we need to provide an implementation of the ServerAuthModule. This implementation should have methods to handle initialize, validateRequest, secureResponse, and cleanSubject operations.

Here is an example of a simple ServerAuthModule implementation:

import javax.security.auth.callback.CallbackHandler;
import javax.security.auth.message.AuthException;
import javax.security.auth.message.AuthStatus;
import javax.security.auth.message.MessageInfo;
import javax.security.auth.message.MessagePolicy;
import javax.security.auth.message.module.ServerAuthModule;

public class CustomServerAuthModule implements ServerAuthModule {

    @Override
    public void initialize(MessagePolicy requestPolicy, MessagePolicy responsePolicy,
                           CallbackHandler handler, @SuppressWarnings("rawtypes") Map options) throws AuthException {
        // Initialize the module
    }

    @Override
    public AuthStatus validateRequest(MessageInfo messageInfo, Subject clientSubject,
                                      Subject serviceSubject) throws AuthException {
        // Perform authentication logic
        return AuthStatus.SEND_SUCCESS;
    }

    @Override
    public AuthStatus secureResponse(MessageInfo messageInfo, Subject serviceSubject)
            throws AuthException {
        // Perform logic to secure the response
        return AuthStatus.SEND_SUCCESS;
    }

    @Override
    public void cleanSubject(MessageInfo messageInfo, Subject subject) throws AuthException {
        // Clean up the subject
    }
}

3. Configuring JASPIC in the web container

The next step is to configure JASPIC in the web container. This involves updating the web.xml or application.xml file of your Java EE application.

Here is an example configuration in web.xml for Apache Tomcat:

<login-config>
    <auth-method>custom</auth-method>
    <realm-name>Custom Authentication</realm-name>
</login-config>

<security-constraint>
    <web-resource-collection>
        <web-resource-name>App Resources</web-resource-name>
    </web-resource-collection>
    <auth-constraint>
        <role-name>USER</role-name>
    </auth-constraint>
</security-constraint>

<security-role>
    <role-name>USER</role-name>
</security-role>

<security-role>
    <role-name>ADMIN</role-name>
</security-role>

<security-role>
    <role-name>SUPERUSER</role-name>
</security-role>

<listener>
    <listener-class>CustomServerAuthModule</listener-class>
</listener>

Note: The <listener-class> should correspond to the fully qualified name of your ServerAuthModule implementation.

Conclusion

By configuring JASPIC in a Java EE web container, you can leverage the flexibility and extensibility it offers for authentication purposes. With JASPIC, you can easily implement custom authentication mechanisms and integrate third-party authentication providers into your web application.