| /* |
| * Copyright (c) 1997, 2009, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code 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 General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| package com.sun.crypto.provider; |
| |
| import javax.crypto.KeyGeneratorSpi; |
| import javax.crypto.SecretKey; |
| import javax.crypto.spec.DESedeKeySpec; |
| import java.security.SecureRandom; |
| import java.security.InvalidParameterException; |
| import java.security.InvalidAlgorithmParameterException; |
| import java.security.InvalidKeyException; |
| import java.security.spec.AlgorithmParameterSpec; |
| |
| /** |
| * This class generates a Triple DES key. |
| * |
| * @author Jan Luehe |
| * |
| */ |
| |
| public final class DESedeKeyGenerator extends KeyGeneratorSpi { |
| |
| private SecureRandom random = null; |
| private int keysize = 168; |
| |
| /** |
| * Empty constructor |
| */ |
| public DESedeKeyGenerator() { |
| } |
| |
| /** |
| * Initializes this key generator. |
| * |
| * @param random the source of randomness for this generator |
| */ |
| protected void engineInit(SecureRandom random) { |
| this.random = random; |
| } |
| |
| /** |
| * Initializes this key generator with the specified parameter |
| * set and a user-provided source of randomness. |
| * |
| * @param params the key generation parameters |
| * @param random the source of randomness for this key generator |
| * |
| * @exception InvalidAlgorithmParameterException if <code>params</code> is |
| * inappropriate for this key generator |
| */ |
| protected void engineInit(AlgorithmParameterSpec params, |
| SecureRandom random) |
| throws InvalidAlgorithmParameterException { |
| throw new InvalidAlgorithmParameterException |
| ("Triple DES key generation does not take any parameters"); |
| } |
| |
| /** |
| * Initializes this key generator for a certain keysize, using the given |
| * source of randomness. |
| * |
| * @param keysize the keysize. This is an algorithm-specific |
| * metric specified in number of bits. A keysize with 112 bits of entropy |
| * corresponds to a Triple DES key with 2 intermediate keys, and a keysize |
| * with 168 bits of entropy corresponds to a Triple DES key with 3 |
| * intermediate keys. |
| * @param random the source of randomness for this key generator |
| */ |
| protected void engineInit(int keysize, SecureRandom random) { |
| if ((keysize != 112) && (keysize != 168)) { |
| throw new InvalidParameterException("Wrong keysize: must be " |
| + "equal to 112 or 168"); |
| } |
| this.keysize = keysize; |
| this.engineInit(random); |
| } |
| |
| /** |
| * Generates the Triple DES key. |
| * |
| * @return the new Triple DES key |
| */ |
| protected SecretKey engineGenerateKey() { |
| if (this.random == null) { |
| this.random = SunJCE.RANDOM; |
| } |
| |
| byte[] rawkey = new byte[DESedeKeySpec.DES_EDE_KEY_LEN]; |
| |
| if (keysize == 168) { |
| // 3 intermediate keys |
| this.random.nextBytes(rawkey); |
| |
| // Do parity adjustment for each intermediate key |
| DESKeyGenerator.setParityBit(rawkey, 0); |
| DESKeyGenerator.setParityBit(rawkey, 8); |
| DESKeyGenerator.setParityBit(rawkey, 16); |
| } else { |
| // 2 intermediate keys |
| byte[] tmpkey = new byte[16]; |
| this.random.nextBytes(tmpkey); |
| DESKeyGenerator.setParityBit(tmpkey, 0); |
| DESKeyGenerator.setParityBit(tmpkey, 8); |
| System.arraycopy(tmpkey, 0, rawkey, 0, tmpkey.length); |
| // Copy the first 8 bytes into the last |
| System.arraycopy(tmpkey, 0, rawkey, 16, 8); |
| java.util.Arrays.fill(tmpkey, (byte)0x00); |
| } |
| |
| DESedeKey desEdeKey = null; |
| try { |
| desEdeKey = new DESedeKey(rawkey); |
| } catch (InvalidKeyException ike) { |
| // this never happens |
| throw new RuntimeException(ike.getMessage()); |
| } |
| |
| java.util.Arrays.fill(rawkey, (byte)0x00); |
| |
| return desEdeKey; |
| } |
| } |