| /* |
| * Copyright (c) 2000, 2013, 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. |
| */ |
| |
| /* |
| * |
| * (C) Copyright IBM Corp. 1999 All Rights Reserved. |
| * Copyright 1997 The Open Group Research Institute. All rights reserved. |
| */ |
| |
| package sun.security.krb5.internal.crypto; |
| |
| import sun.security.krb5.Confounder; |
| import sun.security.krb5.KrbCryptoException; |
| import sun.security.krb5.internal.*; |
| |
| abstract class DesCbcEType extends EType { |
| protected abstract byte[] calculateChecksum(byte[] data, int size) |
| throws KrbCryptoException; |
| |
| public int blockSize() { |
| return 8; |
| } |
| |
| public int keyType() { |
| return Krb5.KEYTYPE_DES; |
| } |
| |
| public int keySize() { |
| return 8; |
| } |
| |
| /** |
| * Encrypts the data using DES in CBC mode. |
| * @param data the buffer for plain text. |
| * @param key the key to encrypt the data. |
| * @return the buffer for encrypted data. |
| * |
| * @written by Yanni Zhang, Dec 6 99. |
| */ |
| |
| public byte[] encrypt(byte[] data, byte[] key, int usage) |
| throws KrbCryptoException { |
| byte[] ivec = new byte[keySize()]; |
| return encrypt(data, key, ivec, usage); |
| } |
| |
| /** |
| * Encrypts the data using DES in CBC mode. |
| * @param data the buffer for plain text. |
| * @param key the key to encrypt the data. |
| * @param ivec initialization vector. |
| * @return buffer for encrypted data. |
| * |
| * @modified by Yanni Zhang, Feb 24 00. |
| */ |
| public byte[] encrypt(byte[] data, byte[] key, byte[] ivec, |
| int usage) throws KrbCryptoException { |
| |
| /* |
| * To meet export control requirements, double check that the |
| * key being used is no longer than 64 bits. |
| * |
| * Note that from a protocol point of view, an |
| * algorithm that is not DES will be rejected before this |
| * point. Also, a DES key that is not 64 bits will be |
| * rejected by a good implementations of JCE. |
| */ |
| if (key.length > 8) |
| throw new KrbCryptoException("Invalid DES Key!"); |
| |
| int new_size = data.length + confounderSize() + checksumSize(); |
| byte[] new_data; |
| byte pad; |
| /*Data padding: using Kerberos 5 GSS-API mechanism (1.2.2.3), Jun 1996. |
| *Before encryption, plain text data is padded to the next highest multiple of blocksize. |
| *by appending between 1 and 8 bytes, the value of each such byte being the total number |
| *of pad bytes. For example, if new_size = 10, blockSize is 8, we should pad 2 bytes, |
| *and the value of each byte is 2. |
| *If plaintext data is a multiple of blocksize, we pad a 8 bytes of 8. |
| */ |
| if (new_size % blockSize() == 0) { |
| new_data = new byte[new_size + blockSize()]; |
| pad = (byte)8; |
| } |
| else { |
| new_data = new byte[new_size + blockSize() - new_size % blockSize()]; |
| pad = (byte)(blockSize() - new_size % blockSize()); |
| } |
| for (int i = new_size; i < new_data.length; i++) { |
| new_data[i] = pad; |
| } |
| byte[] conf = Confounder.bytes(confounderSize()); |
| System.arraycopy(conf, 0, new_data, 0, confounderSize()); |
| System.arraycopy(data, 0, new_data, startOfData(), data.length); |
| byte[] cksum = calculateChecksum(new_data, new_data.length); |
| System.arraycopy(cksum, 0, new_data, startOfChecksum(), |
| checksumSize()); |
| byte[] cipher = new byte[new_data.length]; |
| Des.cbc_encrypt(new_data, cipher, key, ivec, true); |
| return cipher; |
| } |
| |
| /** |
| * Decrypts the data using DES in CBC mode. |
| * @param cipher the input buffer. |
| * @param key the key to decrypt the data. |
| * |
| * @written by Yanni Zhang, Dec 6 99. |
| */ |
| public byte[] decrypt(byte[] cipher, byte[] key, int usage) |
| throws KrbApErrException, KrbCryptoException{ |
| byte[] ivec = new byte[keySize()]; |
| return decrypt(cipher, key, ivec, usage); |
| } |
| |
| /** |
| * Decrypts the data using DES in CBC mode. |
| * @param cipher the input buffer. |
| * @param key the key to decrypt the data. |
| * @param ivec initialization vector. |
| * |
| * @modified by Yanni Zhang, Dec 6 99. |
| */ |
| public byte[] decrypt(byte[] cipher, byte[] key, byte[] ivec, int usage) |
| throws KrbApErrException, KrbCryptoException { |
| |
| /* |
| * To meet export control requirements, double check that the |
| * key being used is no longer than 64 bits. |
| * |
| * Note that from a protocol point of view, an |
| * algorithm that is not DES will be rejected before this |
| * point. Also, a DES key that is not 64 bits will be |
| * rejected by a good JCE provider. |
| */ |
| if (key.length > 8) |
| throw new KrbCryptoException("Invalid DES Key!"); |
| |
| byte[] data = new byte[cipher.length]; |
| Des.cbc_encrypt(cipher, data, key, ivec, false); |
| if (!isChecksumValid(data)) |
| throw new KrbApErrException(Krb5.KRB_AP_ERR_BAD_INTEGRITY); |
| return data; |
| } |
| |
| private void copyChecksumField(byte[] data, byte[] cksum) { |
| for (int i = 0; i < checksumSize(); i++) |
| data[startOfChecksum() + i] = cksum[i]; |
| } |
| |
| private byte[] checksumField(byte[] data) { |
| byte[] result = new byte[checksumSize()]; |
| for (int i = 0; i < checksumSize(); i++) |
| result[i] = data[startOfChecksum() + i]; |
| return result; |
| } |
| |
| private void resetChecksumField(byte[] data) { |
| for (int i = startOfChecksum(); i < startOfChecksum() + |
| checksumSize(); i++) |
| data[i] = 0; |
| } |
| |
| /* |
| // Not used. |
| public void setChecksum(byte[] data, int size) throws KrbCryptoException{ |
| resetChecksumField(data); |
| byte[] cksum = calculateChecksum(data, size); |
| copyChecksumField(data, cksum); |
| } |
| */ |
| |
| private byte[] generateChecksum(byte[] data) throws KrbCryptoException{ |
| byte[] cksum1 = checksumField(data); |
| resetChecksumField(data); |
| byte[] cksum2 = calculateChecksum(data, data.length); |
| copyChecksumField(data, cksum1); |
| return cksum2; |
| } |
| |
| private boolean isChecksumEqual(byte[] cksum1, byte[] cksum2) { |
| if (cksum1 == cksum2) |
| return true; |
| if ((cksum1 == null && cksum2 != null) || |
| (cksum1 != null && cksum2 == null)) |
| return false; |
| if (cksum1.length != cksum2.length) |
| return false; |
| for (int i = 0; i < cksum1.length; i++) |
| if (cksum1[i] != cksum2[i]) |
| return false; |
| return true; |
| } |
| |
| protected boolean isChecksumValid(byte[] data) throws KrbCryptoException { |
| byte[] cksum1 = checksumField(data); |
| byte[] cksum2 = generateChecksum(data); |
| return isChecksumEqual(cksum1, cksum2); |
| } |
| } |