1 /*
2 * Copyright (c) 2003, 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
26 package com.sun.crypto.provider;
27
28 import java.security.*;
29 import java.security.spec.AlgorithmParameterSpec;
30
31 import javax.crypto.*;
32 import javax.crypto.spec.SecretKeySpec;
33
34 /**
35 * KeyGeneratore core implementation and individual key generator
36 * implementations. Because of US export regulations, we cannot use
37 * subclassing to achieve code sharing between the key generator
38 * implementations for our various algorithms. Instead, we have the
39 * core implementation in this KeyGeneratorCore class, which is used
40 * by the individual implementations. See those further down in this
41 * file.
42 *
43 * @since 1.5
44 * @author Andreas Sterbenz
45 */
46 final class KeyGeneratorCore {
47
48 // algorithm name to use for the generator keys
49 private final String name;
50
51 // default key size in bits
52 private final int defaultKeySize;
53
54 // current key size in bits
55 private int keySize;
56
57 // PRNG to use
58 private SecureRandom random;
59
60 /**
61 * Construct a new KeyGeneratorCore object with the specified name
62 * and defaultKeySize. Initialize to default key size in case the
63 * application does not call any of the init() methods.
64 */
65 KeyGeneratorCore(String name, int defaultKeySize) {
66 this.name = name;
67 this.defaultKeySize = defaultKeySize;
68 implInit(null);
69 }
70
71 // implementation for engineInit(), see JCE doc
72 // reset keySize to default
73 void implInit(SecureRandom random) {
74 this.keySize = defaultKeySize;
75 this.random = random;
76 }
77
78 // implementation for engineInit(), see JCE doc
79 // we do not support any parameters
80 void implInit(AlgorithmParameterSpec params, SecureRandom random)
81 throws InvalidAlgorithmParameterException {
82 throw new InvalidAlgorithmParameterException
83 (name + " key generation does not take any parameters");
84 }
85
86 // implementation for engineInit(), see JCE doc
87 // we enforce a general 40 bit minimum key size for security
88 void implInit(int keysize, SecureRandom random) {
89 if (keysize < 40) {
90 throw new InvalidParameterException
91 ("Key length must be at least 40 bits");
92 }
93 this.keySize = keysize;
94 this.random = random;
95 }
96
97 // implementation for engineInit(), see JCE doc
98 // generate the key
99 SecretKey implGenerateKey() {
100 if (random == null) {
101 random = SunJCE.getRandom();
102 }
103 byte[] b = new byte[(keySize + 7) >> 3];
104 random.nextBytes(b);
105 return new SecretKeySpec(b, name);
106 }
107
108 // nested static classes for the HmacSHA-2 family of key generator
109 abstract static class HmacSHA2KG extends KeyGeneratorSpi {
110 private final KeyGeneratorCore core;
111 protected HmacSHA2KG(String algoName, int len) {
112 core = new KeyGeneratorCore(algoName, len);
113 }
114 protected void engineInit(SecureRandom random) {
115 core.implInit(random);
116 }
117 protected void engineInit(AlgorithmParameterSpec params,
118 SecureRandom random) throws InvalidAlgorithmParameterException {
119 core.implInit(params, random);
120 }
121 protected void engineInit(int keySize, SecureRandom random) {
122 core.implInit(keySize, random);
123 }
124 protected SecretKey engineGenerateKey() {
125 return core.implGenerateKey();
126 }
127
128 public static final class SHA224 extends HmacSHA2KG {
129 public SHA224() {
130 super("HmacSHA224", 224);
131 }
132 }
133 public static final class SHA256 extends HmacSHA2KG {
134 public SHA256() {
135 super("HmacSHA256", 256);
136 }
137 }
138 public static final class SHA384 extends HmacSHA2KG {
139 public SHA384() {
140 super("HmacSHA384", 384);
141 }
142 }
143 public static final class SHA512 extends HmacSHA2KG {
144 public SHA512() {
145 super("HmacSHA512", 512);
146 }
147 }
148 }
149
150 // nested static class for the RC2 key generator
151 public static final class RC2KeyGenerator extends KeyGeneratorSpi {
152 private final KeyGeneratorCore core;
153 public RC2KeyGenerator() {
154 core = new KeyGeneratorCore("RC2", 128);
155 }
156 protected void engineInit(SecureRandom random) {
157 core.implInit(random);
158 }
159 protected void engineInit(AlgorithmParameterSpec params,
160 SecureRandom random) throws InvalidAlgorithmParameterException {
161 core.implInit(params, random);
162 }
163 protected void engineInit(int keySize, SecureRandom random) {
164 if ((keySize < 40) || (keySize > 1024)) {
165 throw new InvalidParameterException("Key length for RC2"
166 + " must be between 40 and 1024 bits");
167 }
168 core.implInit(keySize, random);
169 }
170 protected SecretKey engineGenerateKey() {
171 return core.implGenerateKey();
172 }
173 }
174
175 // nested static class for the ARCFOUR (RC4) key generator
176 public static final class ARCFOURKeyGenerator extends KeyGeneratorSpi {
177 private final KeyGeneratorCore core;
178 public ARCFOURKeyGenerator() {
179 core = new KeyGeneratorCore("ARCFOUR", 128);
180 }
181 protected void engineInit(SecureRandom random) {
182 core.implInit(random);
183 }
184 protected void engineInit(AlgorithmParameterSpec params,
185 SecureRandom random) throws InvalidAlgorithmParameterException {
186 core.implInit(params, random);
187 }
188 protected void engineInit(int keySize, SecureRandom random) {
189 if ((keySize < 40) || (keySize > 1024)) {
190 throw new InvalidParameterException("Key length for ARCFOUR"
191 + " must be between 40 and 1024 bits");
192 }
193 core.implInit(keySize, random);
194 }
195 protected SecretKey engineGenerateKey() {
196 return core.implGenerateKey();
197 }
198 }
199
200 }