author | valeriep |
Tue, 08 May 2012 17:57:48 -0700 | |
changeset 12685 | 8a448b5b9006 |
parent 10336 | 0bb1999251f8 |
child 20752 | f0f0acea9113 |
permissions | -rw-r--r-- |
2 | 1 |
/* |
10336
0bb1999251f8
7064075: Security libraries don't build with javac -Xlint:all,-deprecation -Werror
jjg
parents:
5506
diff
changeset
|
2 |
* Copyright (c) 1997, 2011, Oracle and/or its affiliates. All rights reserved. |
2 | 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 |
|
5506 | 7 |
* published by the Free Software Foundation. Oracle designates this |
2 | 8 |
* particular file as subject to the "Classpath" exception as provided |
5506 | 9 |
* by Oracle in the LICENSE file that accompanied this code. |
2 | 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 |
* |
|
5506 | 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. |
|
2 | 24 |
*/ |
25 |
||
26 |
package com.sun.crypto.provider; |
|
27 |
||
28 |
import java.security.InvalidKeyException; |
|
29 |
||
30 |
/** |
|
31 |
* This class represents ciphers in Plaintext Cipher Block Chaining (PCBC) |
|
32 |
* mode. |
|
33 |
* |
|
34 |
* <p>This mode is implemented independently of a particular cipher. |
|
35 |
* Ciphers to which this mode should apply (e.g., DES) must be |
|
36 |
* <i>plugged-in</i> using the constructor. |
|
37 |
* |
|
38 |
* <p>NOTE: This class does not deal with buffering or padding. |
|
39 |
* |
|
40 |
* @author Gigi Ankeny |
|
41 |
*/ |
|
42 |
||
43 |
final class PCBC extends FeedbackCipher { |
|
44 |
||
45 |
/* |
|
46 |
* output buffer |
|
47 |
*/ |
|
48 |
private final byte[] k; |
|
49 |
||
50 |
// variables for save/restore calls |
|
51 |
private byte[] kSave = null; |
|
52 |
||
53 |
PCBC(SymmetricCipher embeddedCipher) { |
|
54 |
super(embeddedCipher); |
|
55 |
k = new byte[blockSize]; |
|
56 |
} |
|
57 |
||
58 |
/** |
|
59 |
* Gets the name of this feedback mode. |
|
60 |
* |
|
61 |
* @return the string <code>PCBC</code> |
|
62 |
*/ |
|
63 |
String getFeedback() { |
|
64 |
return "PCBC"; |
|
65 |
} |
|
66 |
||
67 |
/** |
|
68 |
* Initializes the cipher in the specified mode with the given key |
|
69 |
* and iv. |
|
70 |
* |
|
71 |
* @param decrypting flag indicating encryption or decryption |
|
72 |
* @param algorithm the algorithm name |
|
73 |
* @param key the key |
|
74 |
* @param iv the iv |
|
75 |
* |
|
76 |
* @exception InvalidKeyException if the given key is inappropriate for |
|
77 |
* initializing this cipher |
|
78 |
*/ |
|
79 |
void init(boolean decrypting, String algorithm, byte[] key, byte[] iv) |
|
80 |
throws InvalidKeyException { |
|
81 |
if ((key == null) || (iv == null) || (iv.length != blockSize)) { |
|
82 |
throw new InvalidKeyException("Internal error"); |
|
83 |
} |
|
84 |
this.iv = iv; |
|
85 |
reset(); |
|
86 |
embeddedCipher.init(decrypting, algorithm, key); |
|
87 |
} |
|
88 |
||
89 |
/** |
|
90 |
* Resets the iv to its original value. |
|
91 |
* This is used when doFinal is called in the Cipher class, so that the |
|
92 |
* cipher can be reused (with its original iv). |
|
93 |
*/ |
|
94 |
void reset() { |
|
95 |
System.arraycopy(iv, 0, k, 0, blockSize); |
|
96 |
} |
|
97 |
||
98 |
/** |
|
99 |
* Save the current content of this cipher. |
|
100 |
*/ |
|
101 |
void save() { |
|
102 |
if (kSave == null) { |
|
103 |
kSave = new byte[blockSize]; |
|
104 |
} |
|
105 |
System.arraycopy(k, 0, kSave, 0, blockSize); |
|
106 |
||
107 |
} |
|
108 |
||
109 |
/** |
|
110 |
* Restores the content of this cipher to the previous saved one. |
|
111 |
*/ |
|
112 |
void restore() { |
|
113 |
System.arraycopy(kSave, 0, k, 0, blockSize); |
|
114 |
} |
|
115 |
||
116 |
/** |
|
117 |
* Performs encryption operation. |
|
118 |
* |
|
119 |
* <p>The input plain text <code>plain</code>, starting at |
|
120 |
* <code>plainOffset</code> and ending at |
|
121 |
* <code>(plainOffset + len - 1)</code>, is encrypted. |
|
122 |
* The result is stored in <code>cipher</code>, starting at |
|
123 |
* <code>cipherOffset</code>. |
|
124 |
* |
|
125 |
* <p>It is the application's responsibility to make sure that |
|
126 |
* <code>plainLen</code> is a multiple of the embedded cipher's block size, |
|
127 |
* as any excess bytes are ignored. |
|
128 |
* |
|
129 |
* <p>It is also the application's responsibility to make sure that |
|
130 |
* <code>init</code> has been called before this method is called. |
|
131 |
* (This check is omitted here, to avoid double checking.) |
|
132 |
* |
|
133 |
* @param plain the buffer with the input data to be encrypted |
|
134 |
* @param plainOffset the offset in <code>plain</code> |
|
135 |
* @param plainLen the length of the input data |
|
136 |
* @param cipher the buffer for the result |
|
137 |
* @param cipherOffset the offset in <code>cipher</code> |
|
138 |
*/ |
|
139 |
void encrypt(byte[] plain, int plainOffset, int plainLen, |
|
140 |
byte[] cipher, int cipherOffset) |
|
141 |
{ |
|
142 |
int i; |
|
143 |
int endIndex = plainOffset + plainLen; |
|
144 |
||
145 |
for (; plainOffset < endIndex; |
|
146 |
plainOffset += blockSize, cipherOffset += blockSize) { |
|
147 |
for (i=0; i<blockSize; i++) { |
|
10336
0bb1999251f8
7064075: Security libraries don't build with javac -Xlint:all,-deprecation -Werror
jjg
parents:
5506
diff
changeset
|
148 |
k[i] ^= plain[i+plainOffset]; |
2 | 149 |
} |
150 |
embeddedCipher.encryptBlock(k, 0, cipher, cipherOffset); |
|
151 |
for (i = 0; i < blockSize; i++) { |
|
152 |
k[i] = (byte)(plain[i+plainOffset] ^ cipher[i+cipherOffset]); |
|
153 |
} |
|
154 |
} |
|
155 |
} |
|
156 |
||
157 |
/** |
|
158 |
* Performs decryption operation. |
|
159 |
* |
|
160 |
* <p>The input cipher text <code>cipher</code>, starting at |
|
161 |
* <code>cipherOffset</code> and ending at |
|
162 |
* <code>(cipherOffset + len - 1)</code>, is decrypted. |
|
163 |
* The result is stored in <code>plain</code>, starting at |
|
164 |
* <code>plainOffset</code>. |
|
165 |
* |
|
166 |
* <p>It is the application's responsibility to make sure that |
|
167 |
* <code>cipherLen</code> is a multiple of the embedded cipher's block |
|
168 |
* size, as any excess bytes are ignored. |
|
169 |
* |
|
170 |
* <p>It is also the application's responsibility to make sure that |
|
171 |
* <code>init</code> has been called before this method is called. |
|
172 |
* (This check is omitted here, to avoid double checking.) |
|
173 |
* |
|
174 |
* @param cipher the buffer with the input data to be decrypted |
|
175 |
* @param cipherOffset the offset in <code>cipherOffset</code> |
|
176 |
* @param cipherLen the length of the input data |
|
177 |
* @param plain the buffer for the result |
|
178 |
* @param plainOffset the offset in <code>plain</code> |
|
179 |
*/ |
|
180 |
void decrypt(byte[] cipher, int cipherOffset, int cipherLen, |
|
181 |
byte[] plain, int plainOffset) |
|
182 |
{ |
|
183 |
int i; |
|
184 |
int endIndex = cipherOffset + cipherLen; |
|
185 |
||
186 |
for (; cipherOffset < endIndex; |
|
187 |
plainOffset += blockSize, cipherOffset += blockSize) { |
|
188 |
embeddedCipher.decryptBlock(cipher, cipherOffset, |
|
189 |
plain, plainOffset); |
|
190 |
for (i = 0; i < blockSize; i++) { |
|
191 |
plain[i+plainOffset] ^= k[i]; |
|
192 |
} |
|
193 |
for (i = 0; i < blockSize; i++) { |
|
194 |
k[i] = (byte)(plain[i+plainOffset] ^ cipher[i+cipherOffset]); |
|
195 |
} |
|
196 |
} |
|
197 |
} |
|
198 |
} |