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 package org.apache.shiro.crypto.cipher;
20
21 import javax.crypto.KeyGenerator;
22 import java.security.Key;
23 import java.security.NoSuchAlgorithmException;
24
25 /**
26 * Base abstract class for supporting symmetric key cipher algorithms.
27 *
28 * @since 1.0
29 */
30 public abstract class AbstractSymmetricCipherService extends JcaCipherService {
31
32 protected AbstractSymmetricCipherService(String algorithmName) {
33 super(algorithmName);
34 }
35
36 /**
37 * Generates a new {@link java.security.Key Key} suitable for this CipherService's {@link #getAlgorithmName() algorithm}
38 * by calling {@link #generateNewKey(int) generateNewKey(128)} (uses a 128 bit size by default).
39 *
40 * @return a new {@link java.security.Key Key}, 128 bits in length.
41 */
42 public Key generateNewKey() {
43 return generateNewKey(getKeySize());
44 }
45
46 /**
47 * Generates a new {@link Key Key} of the specified size suitable for this CipherService
48 * (based on the {@link #getAlgorithmName() algorithmName} using the JDK {@link javax.crypto.KeyGenerator KeyGenerator}.
49 *
50 * @param keyBitSize the bit size of the key to create
51 * @return the created key suitable for use with this CipherService
52 */
53 public Key generateNewKey(int keyBitSize) {
54 KeyGenerator kg;
55 try {
56 kg = KeyGenerator.getInstance(getAlgorithmName());
57 } catch (NoSuchAlgorithmException e) {
58 String msg = "Unable to acquire " + getAlgorithmName() + " algorithm. This is required to function.";
59 throw new IllegalStateException(msg, e);
60 }
61 kg.init(keyBitSize);
62 return kg.generateKey();
63 }
64
65 }