ClusterLoginModule

All security attributes are carried in the Credentials object. Credentials is used by LoginModules during the authentication process. User supplied attributes from LoginModules are accessed by CallbackHandlers. To access the Credentials object, Hazelcast uses its own specialized CallbackHandler. During initialization of LoginModules, Hazelcast passes this special CallbackHandler into the LoginModule.initialize() method.

LoginModule implementations should create an instance of com.hazelcast.security.CredentialsCallback and call the handle(Callback[] callbacks) method of CallbackHandler during the login process.

CredentialsCallback.getCredentials() returns the supplied Credentials object.

public class CustomLoginModule implements LoginModule {
  CallbackHandler callbackHandler;
  Subject subject;

  public void initialize( Subject subject, CallbackHandler callbackHandler,
                          Map<String, ?> sharedState, Map<String, ?> options ) {
    this.subject = subject;
    this.callbackHandler = callbackHandler;
  }

  public final boolean login() throws LoginException {
    CredentialsCallback callback = new CredentialsCallback();
    try {
      callbackHandler.handle( new Callback[] { callback } );
      credentials = cb.getCredentials();
    } catch ( Exception e ) {
      throw new LoginException( e.getMessage() );
    }
    ...
  }
  ...
}

To use the default Hazelcast permission policy, you must create an instance of com.hazelcast.security.ClusterPrincipal that holds the Credentials object, and you must add it to Subject.principals onLoginModule.commit() as shown below.

public class MyCustomLoginModule implements LoginModule {
  ...
  public boolean commit() throws LoginException {
    ...
    Principal principal = new ClusterPrincipal( credentials );
    subject.getPrincipals().add( principal );

    return true;
  }
  ...
}

Hazelcast has an abstract implementation of LoginModule that does callback and cleanup operations and holds the resulting Credentials instance. LoginModules extending ClusterLoginModule can access Credentials, Subject, LoginModule instances and options, and sharedState maps. Extending the ClusterLoginModule is recommended instead of implementing all required stuff.

package com.hazelcast.security;
...
public abstract class ClusterLoginModule implements LoginModule {

  protected abstract boolean onLogin() throws LoginException;
  protected abstract boolean onCommit() throws LoginException;
  protected abstract boolean onAbort() throws LoginException;
  protected abstract boolean onLogout() throws LoginException;
}



RELATED INFORMATION

Please refer to JAAS Reference Guide for further information.