Example: Using the default authorization token

Example: Using the default authorization token

This topic explains how WAS uses the default authorization token. Consider using the default authorization token when you are looking for a place to add string attributes that get propagated downstream.
However, make sure that the attributes you add to the authorization token are specific to the user that is associated with the authenticated Subject. If they are not specific to a user, the attributes probably belong in the propagation token, which is also propagated with the request. For more information on the propagation token, see Example: Using the default propagation token. To add attributes into the authorization token, plug in a custom login module into the various system login modules that are configured. Any login module configuration that has the com.ibm.ws.security.server.lm.wsMapDefaultInboundLoginModule implementation configured can receive propagated information and can generate propagation information that can be sent outbound to another server.
If propagated attributes are not presented to the login configuration during an initial login, a default authorization token is created in the wsMapDefaultInboundLoginModule login module after the login occurs in the ltpaLoginModule login module. You can obtain a reference to the default authorization token from the login method using the sharedState hashmap. You must plug in the custom login module after the wsMapDefaultInboundLoginModule implementation for WebSphere Application Server to see the default authorization token.
For more information on the JAAS programming model, see Security: Resources for learning.
Whenever you plug a custom login module into the WAS login infrastructure, ensure that the code is trusted. When you add the login module into the app_server_root/classes directory, it has Java 2 Security AllPermissions permissions. IBM recommends that you add your login module and other infrastructure classes into a private directory. However, if you use a private directory, modify the $(WAS_INSTALL_ROOT)/properties/server.policy file so that the private directory, Java archive (JAR) file, or both have the permissions that are needed to run the application programming interfaces (API) that are called from the login module. Because the login module might run after the application code on the call stack, you might consider adding a doPrivileged code block so that you do not need to add additional permissions to your applications. The following sample code shows you how to obtain a reference to the default authorization token from the login method, how to add attributes to the token, and how to read from the existing attributes that are used for authorization.
public customLoginModule() 
{
  public void initialize(Subject subject, CallbackHandler callbackHandler, 
          Map sharedState, Map options) 
  {
     // (For more information on initialization, see
     // Custom login module development for a system login configuration.)

    // Get a reference to the sharedState map that is passed in during initialization.
    _sharedState = sharedState;
  }

  public boolean login() throws LoginException 
  {
     // (For more information on what to do during login, see
     // Custom login module development for a system login configuration.)

    // Look for the default AuthorizationToken in the shared state
    defaultAuthzToken  = (com.ibm.wsspi.security.token.AuthorizationToken) 
       sharedState.get 
          (com.ibm.wsspi.security.auth.callback.Constants.WSAUTHZTOKEN_KEY);

    // Might not always have one of these generated. It depends on the login 
     // configuration setup.
    if (defaultAuthzToken != null)
    {
      try
      {
        // Add a custom attribute
        defaultAuthzToken.addAttribute("key1", "value1");

        // Determine all of the attributes and values that exist in the token.
        java.util.Enumeration listOfAttributes = defaultAuthorizationToken.
              getAttributeNames();
        
        while (listOfAttributes.hasMoreElements())
        {
          String key = (String) listOfAttributes.nextElement();

          String[] values = (String[]) defaultAuthorizationToken.getAttributes (key);

          for (int i=0;  i<values.length; i++)
          {
            System.out.println ("Key: " + key + ", Value[" + i + "]: " 
                  + values[i]);
          }
        }

        // Read the existing uniqueID attribute.
        String[]   uniqueID = defaultAuthzToken.getAttributes 
            (com.ibm.wsspi.security.token.AttributeNameConstants.
               WSCREDENTIAL_UNIQUEID);

          // Getthe uniqueID from the String[]
          String unique_id = (uniqueID != null && 
                uniqueID[0] != null) ? uniqueID[0] : "";

        // Read the existing expiration attribute.
        String[]   expiration = defaultAuthzToken.getAttributes 
            (com.ibm.wsspi.security.token.AttributeNameConstants.
               WSCREDENTIAL_EXPIRATION);

          // An example of getting a long expiration value from the string array.
          long expire_time = 0;
          if (expiration != null && expiration[0] != null) 
            expire_time = Long.parseLong(expiration[0]);

        // Read the existing display name attribute.
        String[]   securityName = defaultAuthzToken.getAttributes 
            (com.ibm.wsspi.security.token.AttributeNameConstants.
               WSCREDENTIAL_SECURITYNAME);

          // Get the display name from the String[]
          String display_name = (securityName != null && 
                securityName[0] != null) ? securityName[0] : "";


        // Read the existing long securityName attribute.
        String[]   longSecurityName = defaultAuthzToken.getAttributes 
          (com.ibm.wsspi.security.token.AttributeNameConstants.
             WSCREDENTIAL_LONGSECURITYNAME);

        // Get the long security name from the String[]
        String long_security_name = (longSecurityName != null && 
              longSecurityName[0] != null) ? longSecurityName[0] : "";


        // Read the existing group attribute.
        String[]   groupList = defaultAuthzToken.getAttributes 
            (com.ibm.wsspi.security.token.AttributeNameConstants.
               WSCREDENTIAL_GROUPS);

        // Get the groups from the String[]
        ArrayList groups = new ArrayList();
        if (groupList != null)
        {
          for (int i=0; i<groupList.length; i++)
          {
            System.out.println ("group[" + i + "] = " + groupList[i]);
            groups.add(groupList[i]);
          }
        }
      }
      catch (Exception e)
      {
        throw new WSLoginFailedException (e.getMessage(), e);
      }
    }

  }

  public boolean commit() throws LoginException 
  {
    // (For more information on what to do during commit, see 
     // Custom login module development for a system login configuration.)

  }

  private java.util.Map _sharedState = null;
  private com.ibm.wsspi.security.token.AuthorizationToken defaultAuthzToken = null;
}
.

Change the token factory that is associated with the default authorization token
When WAS generates a default authorization token, the appserver utilizes the TokenFactory class that is specified using the com.ibm.wsspi.security.token.authorizationTokenFactory property. To modify this property using the console, complete the following steps:

Click Security > Secure administration, applications, and infrastructure.

Under Additional properties, click Custom properties.

The com.ibm.ws.security.ltpa.AuthzPropTokenFactory token factory is the default. This token factory encodes the data, but does not encrypt the data in the authorization token. Because the authorization token typically flows over Common Secure Interoperability V2 (CSIv2) using Secure Sockets Layer (SSL), encrypting the token is not necessary. However, if we need additional security for the authorization token, you can associate a different token factory implementation with this property to get encryption. For example, if you associate the com.ibm.ws.security.ltpa.LTPAToken2Factory token factory with this property, the token uses Advanced Encryption Standard (AES) encryption. However, weigh the performance impacts against your security needs. Adding sensitive information to the authorization token is one reason to change the token factory implementation to something that encrypts rather than just encodes. To perform your own signing and encryption of the default authorization token, implement the following classes:

com.ibm.wsspi.security.ltpa.Token

com.ibm.wsspi.security.ltpa.TokenFactory

Your token factory implementation instantiates and validates your token implementation. You can use the LTPA keys that are passed into the initialize method of the token factory or you can use your own keys. If you use your own keys, they must be the same everywhere to validate the tokens that are generated using those keys. See the API documentation, that is available through a link on the front page of the information center, for more information on implementing your own custom token factory. To associate your token factory with the default authorization token, using the administrative console...

Click Security > Secure administration, applications, and infrastructure.

Under Additional properties, click Custom properties.

Locate the com.ibm.wsspi.security.token.authorizationTokenFactory property and verify that the value of this property matches your custom token factory implementation.

Verify that your implementation classes are put into the app_server_root/classes directory so that the class loader can load the classes.

Verify that your implementation classes are put into the ${USER_INSTALL_ROOT}/classes directory so that the class loader can load the classes.

Related concepts

Security attribute propagation

Related tasks

Propagating security attributes among appservers

Related Reference

Example: Using the default propagation token
Custom login module development for a system login configuration
Security: Resources for learning

Reference topic