01: // BlockCipher - a block encryption template
02: //
03: // Copyright (C) 1996 by Jef Poskanzer <jef@acme.com>. All rights reserved.
04: //
05: // Redistribution and use in source and binary forms, with or without
06: // modification, are permitted provided that the following conditions
07: // are met:
08: // 1. Redistributions of source code must retain the above copyright
09: // notice, this list of conditions and the following disclaimer.
10: // 2. Redistributions in binary form must reproduce the above copyright
11: // notice, this list of conditions and the following disclaimer in the
12: // documentation and/or other materials provided with the distribution.
13: //
14: // THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15: // ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16: // IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17: // ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18: // FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19: // DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20: // OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21: // HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22: // LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23: // OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24: // SUCH DAMAGE.
25: //
26: // Visit the ACME Labs Java page for up-to-date versions of this and other
27: // fine Java utilities: http://www.acme.com/java/
28:
29: package Acme.Crypto;
30:
31: import java.io.*;
32:
33: /// A block encryption template.
34: // <P>
35: // <A HREF="/resources/classes/Acme/Crypto/BlockCipher.java">Fetch the software.</A><BR>
36: // <A HREF="/resources/classes/Acme.tar.gz">Fetch the entire Acme package.</A>
37: // <P>
38: // @see Cipher
39: // @see StreamCipher
40: // @see EncryptedOutputStream
41: // @see EncryptedInputStream
42: // @see DesCipher
43: // @see CbcBlockCipher
44:
45: public abstract class BlockCipher extends Cipher {
46:
47: /// Constructor.
48: public BlockCipher(int keySize, int blockSize) {
49: super (keySize);
50: this .blockSize = blockSize;
51: }
52:
53: /// How big a block is.
54: public int blockSize;
55:
56: /// Return how big a block is.
57: public int blockSize() {
58: return blockSize;
59: }
60:
61: /// Encrypt a block of bytes.
62: public abstract void encrypt(byte[] clearText, int clearOff,
63: byte[] cipherText, int cipherOff);
64:
65: /// Decrypt a block of bytes.
66: public abstract void decrypt(byte[] cipherText, int cipherOff,
67: byte[] clearText, int clearOff);
68:
69: /// Encrypt a block of bytes.
70: public void encrypt(byte[] clearText, byte[] cipherText) {
71: encrypt(clearText, 0, cipherText, 0);
72: }
73:
74: /// Decrypt a block of bytes.
75: public void decrypt(byte[] cipherText, byte[] clearText) {
76: decrypt(cipherText, 0, clearText, 0);
77: }
78:
79: }
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