| /* |
| * Copyright (c) 1997, 2014, 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; |
| import java.security.ProviderException; |
| |
| /** |
| * This class represents ciphers in electronic codebook (ECB) mode. |
| * |
| * <p>This mode is implemented independently of a particular cipher. |
| * Ciphers to which this mode should apply (e.g., DES) must be |
| * <i>plugged-in</i> using the constructor. |
| * |
| * <p>NOTE: This class does not deal with buffering or padding. |
| * |
| * @author Gigi Ankeny |
| */ |
| |
| final class ElectronicCodeBook extends FeedbackCipher { |
| |
| ElectronicCodeBook(SymmetricCipher embeddedCipher) { |
| super(embeddedCipher); |
| } |
| |
| /** |
| * Gets the name of the feedback mechanism |
| * |
| * @return the name of the feedback mechanism |
| */ |
| String getFeedback() { |
| return "ECB"; |
| } |
| |
| /** |
| * Resets the iv to its original value. |
| * This is used when doFinal is called in the Cipher class, so that the |
| * cipher can be reused (with its original iv). |
| */ |
| void reset() { |
| // empty |
| } |
| |
| /** |
| * Save the current content of this cipher. |
| */ |
| void save() {} |
| |
| /** |
| * Restores the content of this cipher to the previous saved one. |
| */ |
| void restore() {} |
| |
| /** |
| * Initializes the cipher in the specified mode with the given key |
| * and iv. |
| * |
| * @param decrypting flag indicating encryption or decryption |
| * @param algorithm the algorithm name |
| * @param key the key |
| * @param iv the iv |
| * |
| * @exception InvalidKeyException if the given key is inappropriate for |
| * initializing this cipher |
| */ |
| void init(boolean decrypting, String algorithm, byte[] key, byte[] iv) |
| throws InvalidKeyException { |
| if ((key == null) || (iv != null)) { |
| throw new InvalidKeyException("Internal error"); |
| } |
| embeddedCipher.init(decrypting, algorithm, key); |
| } |
| |
| /** |
| * Performs encryption operation. |
| * |
| * <p>The input plain text <code>in</code>, starting at |
| * <code>inOff</code> and ending at * <code>(inOff + len - 1)</code>, |
| * is encrypted. The result is stored in <code>out</code>, starting at |
| * <code>outOff</code>. |
| * |
| * @param in the buffer with the input data to be encrypted |
| * @param inOff the offset in <code>plain</code> |
| * @param len the length of the input data |
| * @param out the buffer for the result |
| * @param outOff the offset in <code>cipher</code> |
| * @exception ProviderException if <code>len</code> is not |
| * a multiple of the block size |
| * @return the length of the encrypted data |
| */ |
| int encrypt(byte[] in, int inOff, int len, byte[] out, int outOff) { |
| if ((len % blockSize) != 0) { |
| throw new ProviderException("Internal error in input buffering"); |
| } |
| for (int i = len; i >= blockSize; i -= blockSize) { |
| embeddedCipher.encryptBlock(in, inOff, out, outOff); |
| inOff += blockSize; |
| outOff += blockSize; |
| } |
| return len; |
| } |
| |
| /** |
| * Performs decryption operation. |
| * |
| * <p>The input cipher text <code>in</code>, starting at |
| * <code>inOff</code> and ending at * <code>(inOff + len - 1)</code>, |
| * is decrypted.The result is stored in <code>out</code>, starting at |
| * <code>outOff</code>. |
| * |
| * @param in the buffer with the input data to be decrypted |
| * @param inOff the offset in <code>cipherOffset</code> |
| * @param len the length of the input data |
| * @param out the buffer for the result |
| * @param outOff the offset in <code>plain</code> |
| * @exception ProviderException if <code>len</code> is not |
| * a multiple of the block size |
| * @return the length of the decrypted data |
| */ |
| int decrypt(byte[] in, int inOff, int len, byte[] out, int outOff) { |
| if ((len % blockSize) != 0) { |
| throw new ProviderException("Internal error in input buffering"); |
| } |
| for (int i = len; i >= blockSize; i -= blockSize) { |
| embeddedCipher.decryptBlock(in, inOff, out, outOff); |
| inOff += blockSize; |
| outOff += blockSize; |
| } |
| return len; |
| } |
| } |