| /* |
| * Copyright (c) 1998, 2015, 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 javax.crypto.spec; |
| |
| import java.security.spec.AlgorithmParameterSpec; |
| |
| /** |
| * This class specifies the parameters used with the |
| * <a href="http://tools.ietf.org/html/rfc2040"><i>RC5</i></a> |
| * algorithm. |
| * |
| * <p> The parameters consist of a version number, a rounds count, a word |
| * size, and optionally an initialization vector (IV) (only in feedback mode). |
| * |
| * <p> This class can be used to initialize a {@code Cipher} object that |
| * implements the <i>RC5</i> algorithm as supplied by |
| * <a href="http://www.rsa.com">RSA Security LLC</a>, |
| * or any parties authorized by RSA Security. |
| * |
| * @author Jan Luehe |
| * |
| * @since 1.4 |
| */ |
| public class RC5ParameterSpec implements AlgorithmParameterSpec { |
| |
| private byte[] iv = null; |
| private int version; |
| private int rounds; |
| private int wordSize; // the word size in bits |
| |
| /** |
| * 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. |
| */ |
| public RC5ParameterSpec(int version, int rounds, int wordSize) { |
| this.version = version; |
| this.rounds = rounds; |
| this.wordSize = wordSize; |
| } |
| |
| /** |
| * 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]} and {@code iv[2*(wordSize/8)-1]} 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)} |
| * bytes of the buffer are copied to protect against subsequent |
| * modification. |
| * @exception IllegalArgumentException if {@code iv} is |
| * {@code null} or {@code (iv.length < 2 * (wordSize / 8))} |
| */ |
| public RC5ParameterSpec(int version, int rounds, int wordSize, byte[] iv) { |
| this(version, rounds, wordSize, iv, 0); |
| } |
| |
| /** |
| * 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}, starting at |
| * {@code offset} inclusive. |
| * Note that the size of the IV (block size), starting at |
| * {@code offset} inclusive, must be twice the word size. |
| * The bytes that constitute the IV are those between |
| * {@code iv[offset]} and {@code iv[offset+2*(wordSize/8)-1]} |
| * 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)} |
| * bytes of the buffer beginning at {@code offset} |
| * inclusive are copied to protect against subsequent modification. |
| * @param offset the offset in {@code iv} where the IV starts. |
| * @exception IllegalArgumentException if {@code iv} is |
| * {@code null} or |
| * {@code (iv.length - offset < 2 * (wordSize / 8))} |
| */ |
| public RC5ParameterSpec(int version, int rounds, int wordSize, |
| byte[] iv, int offset) { |
| this.version = version; |
| this.rounds = rounds; |
| this.wordSize = wordSize; |
| if (iv == null) throw new IllegalArgumentException("IV missing"); |
| int blockSize = (wordSize / 8) * 2; |
| if (iv.length - offset < blockSize) { |
| throw new IllegalArgumentException("IV too short"); |
| } |
| this.iv = new byte[blockSize]; |
| System.arraycopy(iv, offset, this.iv, 0, blockSize); |
| } |
| |
| /** |
| * Returns the version. |
| * |
| * @return the version. |
| */ |
| public int getVersion() { |
| return this.version; |
| } |
| |
| /** |
| * Returns the number of rounds. |
| * |
| * @return the number of rounds. |
| */ |
| public int getRounds() { |
| return this.rounds; |
| } |
| |
| /** |
| * Returns the word size in bits. |
| * |
| * @return the word size in bits. |
| */ |
| public int getWordSize() { |
| return this.wordSize; |
| } |
| |
| /** |
| * 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. |
| */ |
| public byte[] getIV() { |
| return (iv == null? null:iv.clone()); |
| } |
| |
| /** |
| * 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 {@code null}.) |
| * |
| * @param obj the object to test for equality with this object. |
| * |
| * @return true if the objects are considered equal, false if |
| * {@code obj} is null or otherwise. |
| */ |
| public boolean equals(Object obj) { |
| if (obj == this) { |
| return true; |
| } |
| if (!(obj instanceof RC5ParameterSpec)) { |
| return false; |
| } |
| RC5ParameterSpec other = (RC5ParameterSpec) obj; |
| |
| return ((version == other.version) && |
| (rounds == other.rounds) && |
| (wordSize == other.wordSize) && |
| java.util.Arrays.equals(iv, other.iv)); |
| } |
| |
| /** |
| * Calculates a hash code value for the object. |
| * Objects that are equal will also have the same hashcode. |
| */ |
| public int hashCode() { |
| int retval = 0; |
| if (iv != null) { |
| for (int i = 1; i < iv.length; i++) { |
| retval += iv[i] * i; |
| } |
| } |
| retval += (version + rounds + wordSize); |
| return retval; |
| } |
| } |