001/* 002 * Licensed to the Apache Software Foundation (ASF) under one 003 * or more contributor license agreements. See the NOTICE file 004 * distributed with this work for additional information 005 * regarding copyright ownership. The ASF licenses this file 006 * to you under the Apache License, Version 2.0 (the 007 * "License"); you may not use this file except in compliance 008 * with the License. You may obtain a copy of the License at 009 * 010 * http://www.apache.org/licenses/LICENSE-2.0 011 * 012 * Unless required by applicable law or agreed to in writing, 013 * software distributed under the License is distributed on an 014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 015 * KIND, either express or implied. See the License for the 016 * specific language governing permissions and limitations 017 * under the License. 018 */ 019package org.apache.shiro.crypto; 020 021/** 022 * {@code CipherService} using the {@code Blowfish} cipher algorithm for all encryption, decryption, and key operations. 023 * <p/> 024 * The Blowfish algorithm can support key sizes between {@code 32} and {@code 448} bits<b>*</b>, inclusive. However, 025 * modern cryptanalysis techniques render keys of 80 bits or less mostly worthless - use {@code 128} or more whenever 026 * possible. 027 * <p/> 028 * Note that this class retains the parent class's default {@link OperationMode#CBC CBC} mode of operation 029 * instead of the typical JDK default of {@link OperationMode#ECB ECB}. {@code ECB} should not be used in 030 * security-sensitive environments because {@code ECB} does not allow for initialization vectors, which are 031 * considered necessary for strong encryption. See the {@link DefaultBlockCipherService parent class}'s JavaDoc and the 032 * {@link JcaCipherService JcaCipherService} JavaDoc for more on why the JDK default should not be used and is not 033 * used in this implementation. 034 * <p/> 035 * <b>*</b> Generating and using Blowfish key sizes greater than 128 require installation of the 036 * <a href="http://java.sun.com/javase/downloads/index.jsp">Java Cryptography Extension (JCE) Unlimited Strength 037 * Jurisdiction Policy files</a>. 038 * 039 * @since 1.0 040 */ 041public class BlowfishCipherService extends DefaultBlockCipherService { 042 043 private static final String ALGORITHM_NAME = "Blowfish"; 044 private static final int BLOCK_SIZE = 64; 045 046 /** 047 * Creates a new {@link CipherService} instance using the {@code Blowfish} cipher algorithm with the following 048 * important cipher default attributes: 049 * <table> 050 * <tr> 051 * <th>Attribute</th> 052 * <th>Value</th> 053 * </tr> 054 * <tr> 055 * <td>{@link #setKeySize keySize}</td> 056 * <td>{@code 128} bits</td> 057 * </tr> 058 * <tr> 059 * <td>{@link #setBlockSize blockSize}</td> 060 * <td>{@code 64} bits (required for {@code Blowfish})</td> 061 * </tr> 062 * <tr> 063 * <td>{@link #setMode mode}</td> 064 * <td>{@link OperationMode#CBC CBC}<b>*</b></td> 065 * </tr> 066 * <tr> 067 * <td>{@link #setPaddingScheme paddingScheme}</td> 068 * <td>{@link PaddingScheme#PKCS5 PKCS5}</td> 069 * </tr> 070 * <tr> 071 * <td>{@link #setInitializationVectorSize(int) initializationVectorSize}</td> 072 * <td>{@code 64} bits</td> 073 * </tr> 074 * <tr> 075 * <td>{@link #setGenerateInitializationVectors(boolean) generateInitializationVectors}</td> 076 * <td>{@code true}<b>**</b></td> 077 * </tr> 078 * </table> 079 * <p/> 080 * <b>*</b> The {@link OperationMode#CBC CBC} operation mode is used instead of the JDK default {@code ECB} to 081 * ensure strong encryption. {@code ECB} should not be used in security-sensitive environments - see the 082 * {@link DefaultBlockCipherService DefaultBlockCipherService} class JavaDoc's "Operation Mode" section 083 * for more. 084 * <p/> 085 * <b>**</b>In conjunction with the default {@code CBC} operation mode, initialization vectors are generated by 086 * default to ensure strong encryption. See the {@link JcaCipherService JcaCipherService} class JavaDoc for more. 087 */ 088 public BlowfishCipherService() { 089 super(ALGORITHM_NAME); 090 setInitializationVectorSize(BLOCK_SIZE); //like most block ciphers, the IV size is the same as the block size 091 } 092}