Implementing a custom authorization token for security attribute propagation

This task explains how you might create your own AuthorizationToken implementation, which is set in the login Subject and propagated downstream.

1. Write a custom implementation of the AuthorizationToken interface.
   There are many different methods for implementing the AuthorizationToken interface. However, make sure that the methods required by the AuthorizationToken interface and the token interface are fully implemented.

   After you implement this interface, you can place it in the app_server_root/classes directory. Alternatively, you can place the class in any private directory. However, make sure that the WebSphere® Application Server class loader can locate the class and that it is granted the appropriate permissions. You can add the Java™ archive (JAR) file or directory that contains this class into the server.policy file so that it has the necessary permissions that are needed by the server code.

   After you implement this interface, place it in the profile_root/classes directory. For more information on classes, see Creating a classes subdirectory in your profile for custom classes.

   Tip: All of the token types that are defined by the propagation framework have similar interfaces. Basically, the token types are marker interfaces that implement the com.ibm.wsspi.security.token.Token interface. This interface defines most of the methods. If you plan to implement more than one token type, consider creating an abstract class that implements the com.ibm.wsspi.security.token.Token interface. All of your token implementations, including the AuthorizationToken, might extend the abstract class and then most of the work is completed.

   To see an implementation of AuthorizationToken, see Example: com.ibm.wsspi.security.token.AuthorizationToken implementation

2. Add and receive the custom AuthorizationToken during WebSphere Application Server logins.
   This task is typically accomplished by adding a custom login module to the various application and system login configurations. However, in order to deserialize the information, you must plug in a custom login module, which is discussed in Propagating a custom Java serializable object for security attribute propagation. After the object is instantiated in the login module, you can add the object to the Subject during the commit() method.

   If you want to add information to the Subject to get propagated, see Propagating a custom Java serializable object for security attribute propagation. If you want to ensure that the information is propagated, want to do you own custom serialization, or want to specify the uniqueness for Subject caching purposes, then consider writing your own AuthorizationToken implementation.

   The code sample in Example: custom AuthorizationToken login module shows how to determine if the login is an initial login or a propagation login. The difference between these login types is whether the WSTokenHolderCallback contains propagation data. If the callback does not contain propagation data, initialize a new custom AuthorizationToken implementation and set it into the Subject. If the callback contains propagation data, look for your specific custom AuthorizationToken TokenHolder instance, convert the byte[] back into your custom AuthorizationToken object, and set it back into the Subject. The code sample shows both instances.

   You can make your AuthorizationToken read-only in the commit phase of the login module. If you do not make the token read-only, then attributes can be added within your applications.

3. Add your custom login module to WebSphere Application Server system login configurations that already contain the com.ibm.ws.security.server.lm.wsMapDefaultInboundLoginModule for receiving serialized versions of your custom authorization token.

   Because this login module relies on information in the sharedState added by the com.ibm.ws.security.server.lm.wsMapDefaultInboundLoginModule, add this login module after com.ibm.ws.security.server.lm.wsMapDefaultInboundLoginModule. For information on how to add your custom login module to the existing login configurations, see Developing custom login modules for a system login configuration for JAAS.