1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one
3 * or more contributor license agreements. See the NOTICE file
4 * distributed with this work for additional information
5 * regarding copyright ownership. The ASF licenses this file
6 * to you under the Apache License, Version 2.0 (the
7 * "License"); you may not use this file except in compliance
8 * with the License. You may obtain a copy of the License at
9 *
10 * http://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing,
13 * software distributed under the License is distributed on an
14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15 * KIND, either express or implied. See the License for the
16 * specific language governing permissions and limitations
17 * under the License.
18 *
19 */
20 package org.apache.directory.server.kerberos.shared.crypto.checksum;
21
22
23 import java.security.GeneralSecurityException;
24
25 import javax.crypto.Mac;
26 import javax.crypto.SecretKey;
27 import javax.crypto.spec.SecretKeySpec;
28
29 import org.apache.directory.server.kerberos.shared.crypto.encryption.KeyUsage;
30
31
32 /**
33 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
34 * @version $Rev$, $Date$
35 */
36 class HmacMd5Checksum implements ChecksumEngine
37 {
38 public ChecksumType checksumType()
39 {
40 return ChecksumType.HMAC_MD5;
41 }
42
43
44 public byte[] calculateChecksum( byte[] data, byte[] key, KeyUsage usage )
45 {
46 try
47 {
48 SecretKey sk = new SecretKeySpec( key, "ARCFOUR" );
49
50 Mac mac = Mac.getInstance( "HmacMD5" );
51 mac.init( sk );
52
53 return mac.doFinal( data );
54 }
55 catch ( GeneralSecurityException nsae )
56 {
57 nsae.printStackTrace();
58 return null;
59 }
60 }
61 }