1/*
2 * Copyright (c) 1998, 2013, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.  Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26package com.sun.crypto.provider;
27
28import java.security.SecureRandom;
29import java.security.InvalidParameterException;
30import java.security.InvalidAlgorithmParameterException;
31import java.security.spec.AlgorithmParameterSpec;
32import javax.crypto.KeyGeneratorSpi;
33import javax.crypto.SecretKey;
34import javax.crypto.spec.SecretKeySpec;
35
36/**
37 * This class generates a secret key for use with the Blowfish algorithm.
38 *
39 * @author Jan Luehe
40 *
41 */
42
43public final class BlowfishKeyGenerator extends KeyGeneratorSpi {
44
45    private SecureRandom random = null;
46    private int keysize = 16; // default keysize (in number of bytes)
47
48    /**
49     * Empty constructor
50     */
51    public BlowfishKeyGenerator() {
52    }
53
54    /**
55     * Initializes this key generator.
56     *
57     * @param random the source of randomness for this generator
58     */
59    protected void engineInit(SecureRandom random) {
60        this.random = random;
61    }
62
63    /**
64     * Initializes this key generator with the specified parameter
65     * set and a user-provided source of randomness.
66     *
67     * @param params the key generation parameters
68     * @param random the source of randomness for this key generator
69     *
70     * @exception InvalidAlgorithmParameterException if <code>params</code> is
71     * inappropriate for this key generator
72     */
73    protected void engineInit(AlgorithmParameterSpec params,
74                              SecureRandom random)
75        throws InvalidAlgorithmParameterException
76    {
77        throw new InvalidAlgorithmParameterException
78            ("Blowfish key generation does not take any parameters");
79    }
80
81    /**
82     * Initializes this key generator for a certain keysize, using the given
83     * source of randomness.
84     *
85     * @param keysize the keysize. This is an algorithm-specific
86     * metric specified in number of bits.
87     * @param random the source of randomness for this key generator
88     */
89    protected void engineInit(int keysize, SecureRandom random) {
90        if (((keysize % 8) != 0) || (keysize < 32) || (keysize > 448)) {
91            throw new InvalidParameterException("Keysize must be "
92                                                + "multiple of 8, and can "
93                                                + "only range from 32 to 448 "
94                                                + "(inclusive)");
95        }
96        this.keysize = keysize / 8;
97        this.engineInit(random);
98    }
99
100    /**
101     * Generates a Blowfish key.
102     *
103     * @return the new Blowfish key
104     */
105    protected SecretKey engineGenerateKey() {
106        if (this.random == null) {
107            this.random = SunJCE.getRandom();
108        }
109
110        byte[] keyBytes = new byte[this.keysize];
111        this.random.nextBytes(keyBytes);
112
113        return new SecretKeySpec(keyBytes, "Blowfish");
114    }
115}
116