2 * Copyright (c) 2001-2007 Sun Microsystems, Inc. All rights reserved.
4 * The Sun Project JXTA(TM) Software License
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions are met:
9 * 1. Redistributions of source code must retain the above copyright notice,
10 * this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright notice,
13 * this list of conditions and the following disclaimer in the documentation
14 * and/or other materials provided with the distribution.
16 * 3. The end-user documentation included with the redistribution, if any, must
17 * include the following acknowledgment: "This product includes software
18 * developed by Sun Microsystems, Inc. for JXTA(TM) technology."
19 * Alternately, this acknowledgment may appear in the software itself, if
20 * and wherever such third-party acknowledgments normally appear.
22 * 4. The names "Sun", "Sun Microsystems, Inc.", "JXTA" and "Project JXTA" must
23 * not be used to endorse or promote products derived from this software
24 * without prior written permission. For written permission, please contact
25 * Project JXTA at http://www.jxta.org.
27 * 5. Products derived from this software may not be called "JXTA", nor may
28 * "JXTA" appear in their name, without prior written permission of Sun.
30 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES,
31 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
32 * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL SUN
33 * MICROSYSTEMS OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
34 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
35 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
36 * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
37 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
38 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
39 * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
41 * JXTA is a registered trademark of Sun Microsystems, Inc. in the United
42 * States and other countries.
44 * Please see the license information page at :
45 * <http://www.jxta.org/project/www/license.html> for instructions on use of
46 * the license in source files.
48 * ====================================================================
50 * This software consists of voluntary contributions made by many individuals
51 * on behalf of Project JXTA. For more information on Project JXTA, please see
52 * http://www.jxta.org.
54 * This license is based on the BSD license adopted by the Apache Foundation.
56 package net.jxta.impl.util;
61 import java.math.BigInteger;
62 import java.io.InputStream;
63 import java.io.IOException;
64 import java.io.ByteArrayInputStream;
65 import java.security.MessageDigest;
66 import java.security.NoSuchAlgorithmException;
68 import java.util.logging.Logger;
69 import java.util.logging.Level;
70 import net.jxta.logging.Logging;
74 * A message digest wrapper to provide hashing using java.security.MesssageDigest
76 public class JxtaHash {
77 private final static Logger LOG = Logger.getLogger(JxtaHash.class.getName());
78 public final static String SHA = "SHA";
79 public final static String SHA1 = "SHA1";
80 public final static String MD2 = "MD2";
81 public final static String MD5 = "MD5";
82 public final static String DSA = "DSA";
83 public final static String RSA = "RSA";
84 public final static String SHA1withDSA = "SHA1WITHDSA";
85 private MessageDigest dig = null;
88 * Default JxtaHash constructor, with the default algorithm SHA1
93 dig = MessageDigest.getInstance(SHA1);
94 } catch (NoSuchAlgorithmException ex) {
95 if (Logging.SHOW_FINE && LOG.isLoggable(Level.FINE)) {
96 LOG.fine(ex.toString());
102 * Default JxtaHash constructor, with the default algorithm SHA1
104 * @param expression message to hash
106 public JxtaHash(String expression) {
107 this(SHA1, expression);
111 * Constructor for the JxtaHash object
113 * @deprecated This implementation may produce inconsistent results
114 * based upon varience of the locale. (The locale of getBytes() is
117 * @param algorithm algorithm - the name of the algorithm requested
118 * @param expression expression to digest
121 public JxtaHash(String algorithm, String expression) {
123 this(algorithm, expression.getBytes());
127 * Constructor for the JxtaHash object
129 * @param algorithm algorithm - the name of the algorithm requested
130 * @param expression expression to digest
132 public JxtaHash(String algorithm, byte[] expression) {
134 dig = MessageDigest.getInstance(algorithm);
135 if (expression != null) {
136 dig.update(expression);
138 } catch (NoSuchAlgorithmException ex) {
139 if (Logging.SHOW_FINE && LOG.isLoggable(Level.FINE)) {
140 LOG.fine(ex.toString());
146 * Constructor for the JxtaHash object
148 * @param expression expression to digest
150 public void update(String expression) {
151 if (expression != null) {
152 dig.update(expression.getBytes());
157 * Gets the digest as digestInteger
159 * @return The digestInteger value
161 public BigInteger getDigestInteger() {
163 return new BigInteger(dig.digest());
167 * Gets the digest as digestInteger
169 * @param expression expression to digest
170 * @return The digestInteger value
172 public BigInteger getDigestInteger(byte[] expression) {
174 dig.update(expression);
175 return new BigInteger(dig.digest());
179 * Gets the digest as digestInteger
181 * @param expression expression to digest
182 * @return The digestInteger value
184 public BigInteger getDigestInteger(String expression) {
186 return getDigestInteger(expression.getBytes());
190 * Returns a int whose value is (getDigestInteger mod m).
192 * @param m the modulus.
193 * @return (getDigestInteger mod m).
195 public int mod(long m) {
196 BigInteger bi = getDigestInteger();
197 BigInteger mod = new BigInteger(longToBytes(m));
198 BigInteger result = bi.mod(mod);
200 return result.intValue();
204 * convert a long into the byte array
206 * @param value long value to convert
209 private byte[] longToBytes(long value) {
210 byte[] bytes = new byte[8];
212 for (int eachByte = 0; eachByte < 8; eachByte++) {
213 bytes[eachByte] = (byte) (value >> ((7 - eachByte) * 8L));