| SessionUtils.java |
/*
* The Apache Software License, Version 1.1
*
*
* Copyright (c) 2002-2003 The Apache Software Foundation. All rights
* reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. The end-user documentation included with the redistribution,
* if any, must include the following acknowledgment:
* "This product includes software developed by the
* Apache Software Foundation (http://www.apache.org/)."
* Alternately, this acknowledgment may appear in the software itself,
* if and wherever such third-party acknowledgments normally appear.
*
* 4. The names "Axis" and "Apache Software Foundation" must
* not be used to endorse or promote products derived from this
* software without prior written permission. For written
* permission, please contact apache@apache.org.
*
* 5. Products derived from this software may not be called "Apache",
* nor may "Apache" appear in their name, without prior written
* permission of the Apache Software Foundation.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation. For more
* information on the Apache Software Foundation, please see
* <http://www.apache.org/>.
*/
package org.jboss.axis.utils;
import org.jboss.logging.Logger;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.Random;
/**
* Code borrowed from AuthenticatorBase.java for generating a secure id's.
*/
public class SessionUtils
{
/**
* Field log
*/
private static Logger log = Logger.getLogger(SessionUtils.class.getName());
/**
* The default message digest algorithm to use if we cannot use
* the requested one.
*/
protected static final String DEFAULT_ALGORITHM = "MD5";
/**
* The number of random bytes to include when generating a
* session identifier.
*/
protected static final int SESSION_ID_BYTES = 16;
/**
* The message digest algorithm to be used when generating session
* identifiers. This must be an algorithm supported by the
* <code>java.security.MessageDigest</code> class on your platform.
*/
protected static String algorithm = DEFAULT_ALGORITHM;
/**
* Return the MessageDigest implementation to be used when
* creating session identifiers.
*/
protected static MessageDigest digest = null;
/**
* A random number generator to use when generating session identifiers.
*/
protected static Random random = null;
/**
* The Java class name of the random number generator class to be used
* when generating session identifiers.
*/
protected static String randomClass = "java.security.SecureRandom";
/**
* Host name/ip.
*/
private static String thisHost = null;
/**
* Generate and return a new session identifier.
*
* @return a new session id
*/
public static synchronized String generateSessionId()
{
// Generate a byte array containing a session identifier
byte bytes[] = new byte[SESSION_ID_BYTES];
getRandom().nextBytes(bytes);
bytes = getDigest().digest(bytes);
// Render the result as a String of hexadecimal digits
StringBuffer result = new StringBuffer();
for (int i = 0; i < bytes.length; i++)
{
byte b1 = (byte)((bytes[i] & 0xf0) >> 4);
byte b2 = (byte)(bytes[i] & 0x0f);
if (b1 < 10)
{
result.append((char)('0' + b1));
}
else
{
result.append((char)('A' + (b1 - 10)));
}
if (b2 < 10)
{
result.append((char)('0' + b2));
}
else
{
result.append((char)('A' + (b2 - 10)));
}
}
return (result.toString());
}
/**
* Generate and return a new session identifier.
*
* @return a new session.
*/
public static synchronized Long generateSession()
{
return new Long(getRandom().nextLong());
}
/**
* Return the MessageDigest object to be used for calculating
* session identifiers. If none has been created yet, initialize
* one the first time this method is called.
*
* @return Message Digest
*/
private static synchronized MessageDigest getDigest()
{
if (digest == null)
{
try
{
digest = MessageDigest.getInstance(algorithm);
}
catch (NoSuchAlgorithmException e)
{
try
{
digest = MessageDigest.getInstance(DEFAULT_ALGORITHM);
}
catch (NoSuchAlgorithmException f)
{
digest = null;
}
}
}
return (digest);
}
/**
* Return the random number generator instance we should use for
* generating session identifiers. If there is no such generator
* currently defined, construct and seed a new one.
*
* @return Random object
*/
private static synchronized Random getRandom()
{
if (random == null)
{
try
{
Class clazz = Class.forName(randomClass);
random = (Random)clazz.newInstance();
long seed = System.currentTimeMillis();
char entropy[] = getEntropy().toCharArray();
for (int i = 0; i < entropy.length; i++)
{
long update = ((byte)entropy[i]) << ((i % 8) * 8);
seed ^= update;
}
random.setSeed(seed);
}
catch (Exception e)
{
random = new java.util.Random();
}
}
return (random);
}
/**
* Method getEntropy
*
* @return a unique string
*/
private static String getEntropy()
{
if (null == thisHost)
{
try
{
thisHost = java.net.InetAddress.getLocalHost().getHostName();
}
catch (java.net.UnknownHostException e)
{
log.error(Messages.getMessage("javaNetUnknownHostException00"),
e);
thisHost = "localhost";
}
}
StringBuffer s = new StringBuffer();
// Unique string
s.append(s.hashCode()).append('.').append(System.currentTimeMillis())
.append(".AXIS@").append(thisHost);
return s.toString();
}
}
| SessionUtils.java |