package au.net.aba.crypto.provider;

/*
 * $Id: IDEAKeyGenerator.java,v 1.9 1999/01/18 04:59:31 leachbj Exp $
 * $Author: leachbj $
 *
 * Copyright (C) 1996-1998 Australian Business Access Pty Ltd.
 * All rights reserved.
 * 
 * Use, modification, copying and distribution of this software is subject the
 * terms and conditions of the ABA Public Licence. See the file
 * "PUBLIC_LICENCE" for additional information.
 *
 * If you have not received a copy of the Public Licence, you must destroy all
 * copies of this file immediately. 
 *
 * $Source: /aba/CVSROOT/jdk1.1/src/au.net.aba/crypto/provider/IDEAKeyGenerator.java,v $
 * $Revision: 1.9 $
 * $Date: 1999/01/18 04:59:31 $
 * $State: Exp $
 */
import java.security.InvalidAlgorithmParameterException;
import java.security.spec.AlgorithmParameterSpec;
import au.net.aba.crypto.spec.IDEAKeySpec;
import java.security.SecureRandom;
import javax.crypto.KeyGeneratorSpi;
import javax.crypto.SecretKey;

/**
 * This class is used for generating random IDEA keys.  This class
 * should not be instantiated directly, instead use the
 * javax.crypto.KeyGenerator interface.
 * <p>
 * There is no AlgorithmParameterSpec class defined for IDEA so this
 * generator can only be initialised using the keysize,random
 * initialisation.
 * <p>
 * The keysize is 128 bits.
 */
public class IDEAKeyGenerator extends KeyGeneratorSpi
{
	public final static String ident = "$Id: IDEAKeyGenerator.java,v 1.9 1999/01/18 04:59:31 leachbj Exp $";

	private SecureRandom rand;

	/**
	 * Generates a secret key.
	 *
	 * @return a secret key representing a DES key.
	 */
	protected SecretKey engineGenerateKey()
	{
		byte[]		bytes;

		if (rand == null)
		{
			rand = new SecureRandom();
		}

		bytes = new byte[IDEAKeySpec.IDEA_KEY_LEN];
		rand.nextBytes(bytes);

		return new IDEAKey(bytes);
	}
	/**
	 * Since IDEA keys are of a fixed size, this method does
	 * nothing except set the random source.
	 *
	 * @param strength the strength of the key. This parameter is
	 * 	ignored.
	 * @param random the source of randomness for this key generator
	 */
	protected void engineInit(
		int		strength,
		SecureRandom	random)
	{
		rand = random;
	}
	/**
	 * Initialises the key generator with the given random source.
	 *
	 * @param random	a source of random numbers for this generator.
	 */
	protected void engineInit(
		SecureRandom	random)
	{
		rand = random;
	}
	/**
	 * This method is not implemented as there is no AlgorithmParameterSpec
	 * defined for IDEA.  (Use one of the other initialisation methods!)
	 *
	 * @param params	the algorithm parameter specs for this
	 *		generator.
	 * @param random	a source of random numbers for this generator.
	 * @exception InvalidAlgorithmParameterException	An invalid
	 * 	parameter specification is provided.
	 */
	protected void engineInit(
		AlgorithmParameterSpec	params,
		SecureRandom		random)
		throws InvalidAlgorithmParameterException
	{
		throw new InvalidAlgorithmParameterException("Not Implemented");
	}
}