/*
* JBoss, Home of Professional Open Source
* Copyright 2005, JBoss Inc., and individual contributors as indicated
* by the @authors tag. See the copyright.txt in the distribution for a
* full listing of individual contributors.
*
* This is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This software is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package org.jboss.security.auth.callback;

import java.security.AccessController;
import java.security.PrivilegedActionException;
import java.security.PrivilegedExceptionAction;

import javax.management.MBeanServer;
import javax.management.ObjectName;

import org.jboss.security.util.MBeanServerLocator;

/**
 * PriviledgedActions used by login modules for decoding passwords
 * 
 * @author Scott.Stark@jboss.org
 * @version $Revision: 2 $
 */
class DecodeAction implements PrivilegedExceptionAction<Object>
{
   /** The permission required to access decode, decode64 */
   private static final RuntimePermission decodePermission =
      new RuntimePermission("org.jboss.security.auth.spi.DecodeAction.decode"); 
   
   String password;
   ObjectName serviceName;

   DecodeAction(String password, ObjectName serviceName)
   {
      this.password = password;
      this.serviceName = serviceName;
   }

   /**
    * 
    * @return
    * @throws Exception
    */
   public Object run() throws Exception
   {  
      // Invoke the decodeb64 op
      byte[] secret = decode64(password);
      // Convert to UTF-8 base char array
      String secretPassword = new String(secret, "UTF-8");
      return secretPassword.toCharArray();
   }
   
   /** Decrypt the secret using the cipherKey.
   *
   * @param secret - the encrypted secret to decrypt.
   * @return the decrypted secret
   * @throws Exception
   */
  private byte[] decode64(String secret)
     throws Exception
  {
     SecurityManager sm = System.getSecurityManager();
     if( sm != null )
        sm.checkPermission(decodePermission);

     MBeanServer server = MBeanServerLocator.locateJBoss();
     return (byte[]) server.invoke(serviceName, "decode64", new Object[] {secret}, 
           new String[] {String.class.getName()});
  }
  
   static char[] decode(String password, ObjectName serviceName)
      throws Exception
   {
      DecodeAction action = new DecodeAction(password, serviceName);
      try
      {
         char[] decode = (char[]) AccessController.doPrivileged(action);
         return decode;
      }
      catch(PrivilegedActionException e)
      {
         throw e.getException();
      }
   }
}