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Java > Open Source Codes > Acme > Crypto > BlockCipher


1 // BlockCipher - a block encryption template
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//
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// Copyright (C) 1996 by Jef Poskanzer <jef@acme.com>. All rights reserved.
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//
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// Redistribution and use in source and binary forms, with or without
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// modification, are permitted provided that the following conditions
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// are met:
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// 1. Redistributions of source code must retain the above copyright
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// notice, this list of conditions and the following disclaimer.
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// 2. Redistributions in binary form must reproduce the above copyright
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// notice, this list of conditions and the following disclaimer in the
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// documentation and/or other materials provided with the distribution.
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//
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// THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
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// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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// ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
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// FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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// DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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// OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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// HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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// LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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// OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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// SUCH DAMAGE.
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//
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// Visit the ACME Labs Java page for up-to-date versions of this and other
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// fine Java utilities: http://www.acme.com/java/
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29 package Acme.Crypto;
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31 import java.io.*;
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33 /// A block encryption template.
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// <P>
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// <A HREF="../../../resources/classes/Acme/Crypto/BlockCipher.java">Fetch the software.</A><BR>
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// <A HREF="../../../resources/classes/Acme.tar.gz">Fetch the entire Acme package.</A>
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// <P>
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// @see Cipher
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// @see StreamCipher
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// @see EncryptedOutputStream
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// @see EncryptedInputStream
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// @see DesCipher
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// @see CbcBlockCipher
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45 public abstract class BlockCipher extends Cipher
46     {
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48     /// Constructor.
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public BlockCipher( int keySize, int blockSize )
50     {
51     super( keySize );
52     this.blockSize = blockSize;
53     }
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55     /// How big a block is.
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public int blockSize;
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58     /// Return how big a block is.
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public int blockSize()
60     {
61     return blockSize;
62     }
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64     /// Encrypt a block of bytes.
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public abstract void encrypt( byte[] clearText, int clearOff, byte[] cipherText, int cipherOff );
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67     /// Decrypt a block of bytes.
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public abstract void decrypt( byte[] cipherText, int cipherOff, byte[] clearText, int clearOff );
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70     /// Encrypt a block of bytes.
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public void encrypt( byte[] clearText, byte[] cipherText )
72     {
73     encrypt( clearText, 0, cipherText, 0 );
74     }
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76     /// Decrypt a block of bytes.
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public void decrypt( byte[] cipherText, byte[] clearText )
78     {
79     decrypt( cipherText, 0, clearText, 0 );
80     }
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82     }
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