/* * Copyright (c) 1997, 2007, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package com.sun.crypto.provider; import java.security.InvalidKeyException; /** * This abstract class represents the core of all block ciphers. It allows to * intialize the cipher and encrypt/decrypt single blocks. Larger quantities * are handled by modes, which are subclasses of FeedbackCipher. * * @author Gigi Ankeny * @author Jan Luehe * * * @see AESCrypt * @see DESCrypt * @see DESedeCrypt * @see BlowfishCrypt * @see FeedbackCipher */ abstract class SymmetricCipher { SymmetricCipher() { // empty } /** * Retrieves this cipher's block size. * * @return the block size of this cipher */ abstract int getBlockSize(); /** * Initializes the cipher in the specified mode with the given key. * * @param decrypting flag indicating encryption or decryption * @param algorithm the algorithm name * @param key the key * * @exception InvalidKeyException if the given key is inappropriate for * initializing this cipher */ abstract void init(boolean decrypting, String algorithm, byte[] key) throws InvalidKeyException; /** * Encrypt one cipher block. * *
The input plain
, starting at plainOffset
* and ending at (plainOffset+blockSize-1)
, is encrypted.
* The result is stored in cipher
, starting at
* cipherOffset
.
*
* @param plain the input buffer with the data to be encrypted
* @param plainOffset the offset in plain
* @param cipher the buffer for the encryption result
* @param cipherOffset the offset in cipher
*/
abstract void encryptBlock(byte[] plain, int plainOffset,
byte[] cipher, int cipherOffset);
/**
* Decrypt one cipher block.
*
*
The input cipher
, starting at cipherOffset
* and ending at (cipherOffset+blockSize-1)
, is decrypted.
* The result is stored in plain
, starting at
* plainOffset
.
*
* @param cipher the input buffer with the data to be decrypted
* @param cipherOffset the offset in cipher
* @param plain the buffer for the decryption result
* @param plainOffset the offset in plain
*/
abstract void decryptBlock(byte[] cipher, int cipherOffset,
byte[] plain, int plainOffset);
}