| /* |
| * 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.Checksum; |
| import sun.security.krb5.Confounder; |
| import sun.security.krb5.KrbCryptoException; |
| import sun.security.krb5.internal.*; |
| import javax.crypto.Cipher; |
| import javax.crypto.SecretKey; |
| import javax.crypto.spec.DESKeySpec; |
| import java.security.MessageDigest; |
| import java.security.Provider; |
| import java.security.Security; |
| import java.security.InvalidKeyException; |
| |
| public final class RsaMd5DesCksumType extends CksumType { |
| |
| public RsaMd5DesCksumType() { |
| } |
| |
| public int confounderSize() { |
| return 8; |
| } |
| |
| public int cksumType() { |
| return Checksum.CKSUMTYPE_RSA_MD5_DES; |
| } |
| |
| public boolean isSafe() { |
| return true; |
| } |
| |
| public int cksumSize() { |
| return 24; |
| } |
| |
| public int keyType() { |
| return Krb5.KEYTYPE_DES; |
| } |
| |
| public int keySize() { |
| return 8; |
| } |
| |
| /** |
| * Calculates keyed checksum. |
| * @param data the data used to generate the checksum. |
| * @param size length of the data. |
| * @param key the key used to encrypt the checksum. |
| * @return keyed checksum. |
| * |
| * @modified by Yanni Zhang, 12/08/99. |
| */ |
| public byte[] calculateKeyedChecksum(byte[] data, int size, byte[] key, |
| int usage) throws KrbCryptoException { |
| //prepend confounder |
| byte[] new_data = new byte[size + confounderSize()]; |
| byte[] conf = Confounder.bytes(confounderSize()); |
| System.arraycopy(conf, 0, new_data, 0, confounderSize()); |
| System.arraycopy(data, 0, new_data, confounderSize(), size); |
| |
| //calculate md5 cksum |
| byte[] mdc_cksum = calculateChecksum(new_data, new_data.length); |
| byte[] cksum = new byte[cksumSize()]; |
| System.arraycopy(conf, 0, cksum, 0, confounderSize()); |
| System.arraycopy(mdc_cksum, 0, cksum, confounderSize(), |
| cksumSize() - confounderSize()); |
| |
| //compute modified key |
| byte[] new_key = new byte[keySize()]; |
| System.arraycopy(key, 0, new_key, 0, key.length); |
| for (int i = 0; i < new_key.length; i++) |
| new_key[i] = (byte)(new_key[i] ^ 0xf0); |
| //check for weak keys |
| try { |
| if (DESKeySpec.isWeak(new_key, 0)) { |
| new_key[7] = (byte)(new_key[7] ^ 0xF0); |
| } |
| } catch (InvalidKeyException ex) { |
| // swallow, since it should never happen |
| } |
| byte[] ivec = new byte[new_key.length]; |
| |
| //des-cbc encrypt |
| byte[] enc_cksum = new byte[cksum.length]; |
| Des.cbc_encrypt(cksum, enc_cksum, new_key, ivec, true); |
| return enc_cksum; |
| } |
| |
| /** |
| * Verifies keyed checksum. |
| * @param data the data. |
| * @param size the length of data. |
| * @param key the key used to encrypt the checksum. |
| * @param checksum the checksum. |
| * @return true if verification is successful. |
| * |
| * @modified by Yanni Zhang, 12/08/99. |
| */ |
| public boolean verifyKeyedChecksum(byte[] data, int size, |
| byte[] key, byte[] checksum, int usage) throws KrbCryptoException { |
| //decrypt checksum |
| byte[] cksum = decryptKeyedChecksum(checksum, key); |
| |
| //prepend confounder |
| byte[] new_data = new byte[size + confounderSize()]; |
| System.arraycopy(cksum, 0, new_data, 0, confounderSize()); |
| System.arraycopy(data, 0, new_data, confounderSize(), size); |
| |
| byte[] new_cksum = calculateChecksum(new_data, new_data.length); |
| //extract original cksum value |
| byte[] orig_cksum = new byte[cksumSize() - confounderSize()]; |
| System.arraycopy(cksum, confounderSize(), orig_cksum, 0, |
| cksumSize() - confounderSize()); |
| |
| return isChecksumEqual(orig_cksum, new_cksum); |
| } |
| |
| /** |
| * Decrypts keyed checksum. |
| * @param enc_cksum the buffer for encrypted checksum. |
| * @param key the key. |
| * @return the checksum. |
| * |
| * @modified by Yanni Zhang, 12/08/99. |
| */ |
| private byte[] decryptKeyedChecksum(byte[] enc_cksum, byte[] key) throws KrbCryptoException { |
| //compute modified key |
| byte[] new_key = new byte[keySize()]; |
| System.arraycopy(key, 0, new_key, 0, key.length); |
| for (int i = 0; i < new_key.length; i++) |
| new_key[i] = (byte)(new_key[i] ^ 0xf0); |
| //check for weak keys |
| try { |
| if (DESKeySpec.isWeak(new_key, 0)) { |
| new_key[7] = (byte)(new_key[7] ^ 0xF0); |
| } |
| } catch (InvalidKeyException ex) { |
| // swallow, since it should never happen |
| } |
| byte[] ivec = new byte[new_key.length]; |
| |
| byte[] cksum = new byte[enc_cksum.length]; |
| Des.cbc_encrypt(enc_cksum, cksum, new_key, ivec, false); |
| return cksum; |
| } |
| |
| /** |
| * Calculates checksum using MD5. |
| * @param data the data used to generate the checksum. |
| * @param size length of the data. |
| * @return the checksum. |
| * |
| * @modified by Yanni Zhang, 12/08/99. |
| */ |
| public byte[] calculateChecksum(byte[] data, int size) throws KrbCryptoException{ |
| MessageDigest md5; |
| byte[] result = null; |
| try { |
| md5 = MessageDigest.getInstance("MD5"); |
| } catch (Exception e) { |
| throw new KrbCryptoException("JCE provider may not be installed. " + e.getMessage()); |
| } |
| try { |
| md5.update(data); |
| result = md5.digest(); |
| } catch (Exception e) { |
| throw new KrbCryptoException(e.getMessage()); |
| } |
| return result; |
| } |
| |
| } |