RC5ParameterSpec.java revision 0
2362N/A * Copyright 1998-2007 Sun Microsystems, Inc. All Rights Reserved. 0N/A * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 0N/A * This code is free software; you can redistribute it and/or modify it 0N/A * under the terms of the GNU General Public License version 2 only, as 2362N/A * published by the Free Software Foundation. Sun designates this 0N/A * particular file as subject to the "Classpath" exception as provided 2362N/A * by Sun in the LICENSE file that accompanied this code. 0N/A * This code is distributed in the hope that it will be useful, but WITHOUT 0N/A * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 0N/A * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 0N/A * version 2 for more details (a copy is included in the LICENSE file that 0N/A * accompanied this code). 0N/A * You should have received a copy of the GNU General Public License version 0N/A * 2 along with this work; if not, write to the Free Software Foundation, 0N/A * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 2362N/A * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, 2362N/A * CA 95054 USA or visit www.sun.com if you need additional information or 0N/A * This class specifies the parameters used with the 0N/A * <p> The parameters consist of a version number, a rounds count, a word 0N/A * size, and optionally an initialization vector (IV) (only in feedback mode). 0N/A * <p> This class can be used to initialize a <code>Cipher</code> object that 0N/A * implements the <i>RC5</i> algorithm as supplied by 0N/A * or any parties authorized by RSA Security. 0N/A * Constructs a parameter set for RC5 from the given version, number of * rounds and word size (in bits). * @param version the version. * @param rounds the number of rounds. * @param wordSize the word size in bits. * Constructs a parameter set for RC5 from the given version, number of * rounds, word size (in bits), and IV. * <p> Note that the size of the IV (block size) must be twice the word * size. The bytes that constitute the IV are those between * <code>iv[0]</code> and <code>iv[2*(wordSize/8)-1]</code> inclusive. * @param version the version. * @param rounds the number of rounds. * @param wordSize the word size in bits. * @param iv the buffer with the IV. The first <code>2*(wordSize/8) * </code> bytes of the buffer are copied to protect against subsequent * @exception IllegalArgumentException if <code>iv</code> is * <code>null</code> or <code>(iv.length < 2 * (wordSize / 8))</code> * Constructs a parameter set for RC5 from the given version, number of * rounds, word size (in bits), and IV. * <p> The IV is taken from <code>iv</code>, starting at * <code>offset</code> inclusive. * Note that the size of the IV (block size), starting at * <code>offset</code> inclusive, must be twice the word size. * The bytes that constitute the IV are those between * <code>iv[offset]</code> and <code>iv[offset+2*(wordSize/8)-1]</code> * @param version the version. * @param rounds the number of rounds. * @param wordSize the word size in bits. * @param iv the buffer with the IV. The first <code>2*(wordSize/8) * </code> bytes of the buffer beginning at <code>offset</code> * inclusive are copied to protect against subsequent modification. * @param offset the offset in <code>iv</code> where the IV starts. * @exception IllegalArgumentException if <code>iv</code> is * <code>(iv.length - offset < 2 * (wordSize / 8))</code> * Returns the number of rounds. * @return the number of rounds. * Returns the word size in bits. * @return the word size in bits. * Returns the IV or null if this parameter set does not contain an IV. * @return the IV or null if this parameter set does not contain an IV. * Returns a new array each time this method is called. * Tests for equality between the specified object and this * object. Two RC5ParameterSpec objects are considered equal if their * version numbers, number of rounds, word sizes, and IVs are equal. * (Two IV references are considered equal if both are <tt>null</tt>.) * @param obj the object to test for equality with this object. * @return true if the objects are considered equal, false if * <code>obj</code> is null or otherwise. * Calculates a hash code value for the object. * Objects that are equal will also have the same hashcode.