| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You under the Apache License, Version 2.0 |
| * (the "License"); you may not use this file except in compliance with |
| * the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package javax.crypto.spec; |
| |
| import java.security.InvalidKeyException; |
| import java.security.spec.KeySpec; |
| |
| import org.apache.harmony.crypto.internal.nls.Messages; |
| |
| /** |
| * The key specification for a DES key. |
| */ |
| public class DESKeySpec implements KeySpec { |
| |
| /** |
| * The length of a DES key in bytes. |
| */ |
| public static final int DES_KEY_LEN = 8; |
| |
| private final byte[] key; |
| |
| // DES weak and semi-weak keys |
| // Got from: |
| // FIP PUB 74 |
| // FEDERAL INFORMATION PROCESSING STANDARDS PUBLICATION 1981 |
| // GUIDELINES FOR IMPLEMENTING AND USING THE NBS DATA ENCRYPTION STANDARD |
| // http://www.dice.ucl.ac.be/crypto/standards/fips/fip74/fip74-1.pdf |
| private static final byte[][] SEMIWEAKS = { |
| {(byte) 0xE0, (byte) 0x01, (byte) 0xE0, (byte) 0x01, |
| (byte) 0xF1, (byte) 0x01, (byte) 0xF1, (byte) 0x01}, |
| |
| {(byte) 0x01, (byte) 0xE0, (byte) 0x01, (byte) 0xE0, |
| (byte) 0x01, (byte) 0xF1, (byte) 0x01, (byte) 0xF1}, |
| |
| {(byte) 0xFE, (byte) 0x1F, (byte) 0xFE, (byte) 0x1F, |
| (byte) 0xFE, (byte) 0x0E, (byte) 0xFE, (byte) 0x0E}, |
| |
| {(byte) 0x1F, (byte) 0xFE, (byte) 0x1F, (byte) 0xFE, |
| (byte) 0x0E, (byte) 0xFE, (byte) 0x0E, (byte) 0xFE}, |
| |
| {(byte) 0xE0, (byte) 0x1F, (byte) 0xE0, (byte) 0x1F, |
| (byte) 0xF1, (byte) 0x0E, (byte) 0xF1, (byte) 0x0E}, |
| |
| {(byte) 0x1F, (byte) 0xE0, (byte) 0x1F, (byte) 0xE0, |
| (byte) 0x0E, (byte) 0xF1, (byte) 0x0E, (byte) 0xF1}, |
| |
| {(byte) 0x01, (byte) 0xFE, (byte) 0x01, (byte) 0xFE, |
| (byte) 0x01, (byte) 0xFE, (byte) 0x01, (byte) 0xFE}, |
| |
| {(byte) 0xFE, (byte) 0x01, (byte) 0xFE, (byte) 0x01, |
| (byte) 0xFE, (byte) 0x01, (byte) 0xFE, (byte) 0x01}, |
| |
| {(byte) 0x01, (byte) 0x1F, (byte) 0x01, (byte) 0x1F, |
| (byte) 0x01, (byte) 0x0E, (byte) 0x01, (byte) 0x0E}, |
| |
| {(byte) 0x1F, (byte) 0x01, (byte) 0x1F, (byte) 0x01, |
| (byte) 0x0E, (byte) 0x01, (byte) 0x0E, (byte) 0x01}, |
| |
| {(byte) 0xE0, (byte) 0xFE, (byte) 0xE0, (byte) 0xFE, |
| (byte) 0xF1, (byte) 0xFE, (byte) 0xF1, (byte) 0xFE}, |
| |
| {(byte) 0xFE, (byte) 0xE0, (byte) 0xFE, (byte) 0xE0, |
| (byte) 0xFE, (byte) 0xF1, (byte) 0xFE, (byte) 0xF1}, |
| |
| {(byte) 0x01, (byte) 0x01, (byte) 0x01, (byte) 0x01, |
| (byte) 0x01, (byte) 0x01, (byte) 0x01, (byte) 0x01}, |
| |
| {(byte) 0xFE, (byte) 0xFE, (byte) 0xFE, (byte) 0xFE, |
| (byte) 0xFE, (byte) 0xFE, (byte) 0xFE, (byte) 0xFE}, |
| |
| {(byte) 0xE0, (byte) 0xE0, (byte) 0xE0, (byte) 0xE0, |
| (byte) 0xF1, (byte) 0xF1, (byte) 0xF1, (byte) 0xF1}, |
| |
| {(byte) 0x1F, (byte) 0x1F, (byte) 0x1F, (byte) 0x1F, |
| (byte) 0x0E, (byte) 0x0E, (byte) 0x0E, (byte) 0x0E}, |
| |
| }; |
| |
| /** |
| * Creates a new <code>DESKeySpec</code> from the first 8 bytes of the |
| * specified key data. |
| * |
| * @param key |
| * the key data. |
| * @throws InvalidKeyException |
| * if the length of the specified key data is less than 8. |
| */ |
| public DESKeySpec(byte[] key) throws InvalidKeyException { |
| this(key, 0); |
| } |
| |
| /** |
| * Creates a new <code>DESKeySpec</code> from the first 8 bytes of the |
| * specified key data starting at <code>offset</code>. |
| * |
| * @param key |
| * the key data |
| * @param offset |
| * the offset to start at. |
| * @throws InvalidKeyException |
| * if the length of the specified key data starting at offset is |
| * less than 8. |
| */ |
| public DESKeySpec(byte[] key, int offset) |
| throws InvalidKeyException { |
| if (key == null) { |
| throw new NullPointerException(Messages.getString("crypto.2F")); //$NON-NLS-1$ |
| } |
| if (key.length - offset < DES_KEY_LEN) { |
| throw new InvalidKeyException( |
| Messages.getString("crypto.40")); //$NON-NLS-1$ |
| } |
| this.key = new byte[DES_KEY_LEN]; |
| System.arraycopy(key, offset, this.key, 0, DES_KEY_LEN); |
| } |
| |
| /** |
| * Returns a copy of the key. |
| * |
| * @return a copy of the key. |
| */ |
| public byte[] getKey() { |
| byte[] result = new byte[DES_KEY_LEN]; |
| System.arraycopy(this.key, 0, result, 0, DES_KEY_LEN); |
| return result; |
| } |
| |
| /** |
| * Returns whether the specified key data starting at <code>offset</code> is |
| * <i>parity-adjusted</i>. |
| * |
| * @param key |
| * the key data. |
| * @param offset |
| * the offset to start checking at. |
| * @return {@code true} if the specified key data is parity-adjusted, |
| * {@code false} otherwise. |
| * @throws InvalidKeyException |
| * if the length of the key data starting at offset is less than |
| * 8, or the key is null. |
| */ |
| public static boolean isParityAdjusted(byte[] key, int offset) |
| throws InvalidKeyException { |
| if (key == null) { |
| throw new InvalidKeyException(Messages.getString("crypto.2F")); //$NON-NLS-1$ |
| } |
| if (key.length - offset < DES_KEY_LEN) { |
| throw new InvalidKeyException( |
| Messages.getString("crypto.40")); //$NON-NLS-1$ |
| } |
| |
| int byteKey = 0; |
| |
| for (int i = offset; i < DES_KEY_LEN; i++) { |
| byteKey = key[i]; |
| |
| byteKey ^= byteKey >> 1; |
| byteKey ^= byteKey >> 2; |
| byteKey ^= byteKey >> 4; |
| |
| if ((byteKey & 1) == 0) { |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| /** |
| * Returns whether the specified key data starting at <code>offset</code> is |
| * weak or semi-weak. |
| * |
| * @param key |
| * the key data. |
| * @param offset |
| * the offset to start checking at. |
| * @return {@code true} if the specified key data is weak or semi-weak. |
| * @throws InvalidKeyException |
| * if the length of the key data starting at offset is less than |
| * 8, or it is null. |
| */ |
| public static boolean isWeak(byte[] key, int offset) |
| throws InvalidKeyException { |
| if (key == null) { |
| throw new InvalidKeyException(Messages.getString("crypto.2F")); //$NON-NLS-1$ |
| } |
| if (key.length - offset < DES_KEY_LEN) { |
| throw new InvalidKeyException( |
| Messages.getString("crypto.40")); //$NON-NLS-1$ |
| } |
| I: |
| for (int i=0; i<SEMIWEAKS.length; i++) { |
| for (int j=0; j<DES_KEY_LEN; j++) { |
| if (SEMIWEAKS[i][j] != key[offset+j]) { |
| continue I; |
| } |
| } |
| return true; |
| } |
| return false; |
| } |
| } |
| |