| /* |
| * Copyright (c) 1997, 2011, 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 javax.crypto.spec; |
| |
| import java.security.InvalidKeyException; |
| |
| /** |
| * This class specifies a DES-EDE ("triple-DES") key. |
| * |
| * @author Jan Luehe |
| * |
| * @since 1.4 |
| */ |
| public class DESedeKeySpec implements java.security.spec.KeySpec { |
| |
| /** |
| * The constant which defines the length of a DESede key in bytes. |
| */ |
| public static final int DES_EDE_KEY_LEN = 24; |
| |
| private byte[] key; |
| |
| /** |
| * Creates a DESedeKeySpec object using the first 24 bytes in |
| * <code>key</code> as the key material for the DES-EDE key. |
| * |
| * <p> The bytes that constitute the DES-EDE key are those between |
| * <code>key[0]</code> and <code>key[23]</code> inclusive |
| * |
| * @param key the buffer with the DES-EDE key material. The first |
| * 24 bytes of the buffer are copied to protect against subsequent |
| * modification. |
| * |
| * @exception NullPointerException if <code>key</code> is null. |
| * @exception InvalidKeyException if the given key material is shorter |
| * than 24 bytes. |
| */ |
| public DESedeKeySpec(byte[] key) throws InvalidKeyException { |
| this(key, 0); |
| } |
| |
| /** |
| * Creates a DESedeKeySpec object using the first 24 bytes in |
| * <code>key</code>, beginning at <code>offset</code> inclusive, |
| * as the key material for the DES-EDE key. |
| * |
| * <p> The bytes that constitute the DES-EDE key are those between |
| * <code>key[offset]</code> and <code>key[offset+23]</code> inclusive. |
| * |
| * @param key the buffer with the DES-EDE key material. The first |
| * 24 bytes of the buffer beginning at <code>offset</code> inclusive |
| * are copied to protect against subsequent modification. |
| * @param offset the offset in <code>key</code>, where the DES-EDE key |
| * material starts. |
| * |
| * @exception NullPointerException if <code>key</code> is null. |
| * @exception InvalidKeyException if the given key material, starting at |
| * <code>offset</code> inclusive, is shorter than 24 bytes |
| */ |
| public DESedeKeySpec(byte[] key, int offset) throws InvalidKeyException { |
| if (key.length - offset < 24) { |
| throw new InvalidKeyException("Wrong key size"); |
| } |
| this.key = new byte[24]; |
| System.arraycopy(key, offset, this.key, 0, 24); |
| } |
| |
| /** |
| * Returns the DES-EDE key. |
| * |
| * @return the DES-EDE key. Returns a new array |
| * each time this method is called. |
| */ |
| public byte[] getKey() { |
| return this.key.clone(); |
| } |
| |
| /** |
| * Checks if the given DES-EDE key, starting at <code>offset</code> |
| * inclusive, is parity-adjusted. |
| * |
| * @param key a byte array which holds the key value |
| * @param offset the offset into the byte array |
| * @return true if the given DES-EDE key is parity-adjusted, false |
| * otherwise |
| * |
| * @exception NullPointerException if <code>key</code> is null. |
| * @exception InvalidKeyException if the given key material, starting at |
| * <code>offset</code> inclusive, is shorter than 24 bytes |
| */ |
| public static boolean isParityAdjusted(byte[] key, int offset) |
| throws InvalidKeyException { |
| if (key.length - offset < 24) { |
| throw new InvalidKeyException("Wrong key size"); |
| } |
| if (DESKeySpec.isParityAdjusted(key, offset) == false |
| || DESKeySpec.isParityAdjusted(key, offset + 8) == false |
| || DESKeySpec.isParityAdjusted(key, offset + 16) == false) { |
| return false; |
| } |
| return true; |
| } |
| } |