util.java

一个java写的加密算法

/*
 * Copyright 2004-2005 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

package samples.connectors.mailconnector.ra.outbound;

import java.io.*;
import java.util.*;
import java.util.logging.*;
import javax.naming.*;

import javax.resource.ResourceException;
import javax.resource.spi.*;
import javax.resource.spi.security.*;
import javax.security.auth.Subject;

import javax.security.auth.Subject;
import java.security.AccessController;
import java.security.PrivilegedAction;

/**
 * Utilities. The following methods handle authentication.
 *
 *  Note: If subject is null, credential is created from
 *        the ConnectionRequestInfo user/password info.
 *        Otherwise it is created using the subject object.
 *
 * @author Alejandro E. Murillo
 */

public class Util 
{
    static Logger logger = 
        Logger.getLogger("samples.connectors.mailconnector.ra.outbound",
            "samples.connectors.mailconnector.ra.outbound.LocalStrings");
    static ResourceBundle resource = 
        java.util.ResourceBundle.getBundle("samples.connectors.mailconnector.ra.outbound.LocalStrings");

    /**
     * Returns a PasswordCredential.
     *
     * @param mcf  a ManagedConnectionFactory object
     * @param subject  security context as JAAS subject
     * @param info  ConnectionRequestInfo instance
     *
     * @return a PasswordCredential
     */

    static public PasswordCredential getPasswordCredential
        (final ManagedConnectionFactory mcf,
         final Subject subject, ConnectionRequestInfo info)
        throws ResourceException 
    {
        if (subject == null) 
	{
            if (info == null) 
	    {
	        //logger.info("\tUtil::GetPasswordCred: INFO is null");
                return null;
            } else {

                ConnectionRequestInfoImpl myinfo =
                    (ConnectionRequestInfoImpl) info;

		// Can't create a PC with null values

		if (myinfo.getUserName() == null || myinfo.getPassword() == null)
		{
		    //logger.info("\tUtil::GetPasswordCred: User or password is null");
		    return null;
		}

		char [] password = myinfo.getPassword().toCharArray();

                PasswordCredential pc = 
                    new PasswordCredential(myinfo.getUserName(), password);

                pc.setManagedConnectionFactory(mcf);
		//logger.info("\tUtil::GetPasswordCred: returning a created PC");
                return pc;
            }
        } else {
            PasswordCredential pc = 
            (PasswordCredential) AccessController.doPrivileged(
                new PrivilegedAction() 
                {
                    public Object run() 
		    {
                        Set creds = subject.getPrivateCredentials(
                            PasswordCredential.class);
                        Iterator iter = creds.iterator();
                        while (iter.hasNext()) 
			{
                            PasswordCredential temp = 
                                (PasswordCredential) iter.next();
                            if (temp != null &&
                                temp.getManagedConnectionFactory() != null &&
                                temp.getManagedConnectionFactory().equals(mcf)) 
			    {
			        return temp;
                            }
                        }
                        return null;
                    }
                });
            if (pc == null) 
	    {
                throw new java.lang.SecurityException( 
                    resource.getString("util.no_credential"));
            } else {
	        //logger.info("\tUtil::GetPasswordCred: returning a FOUND PC");
                return pc;
            }
        }
    }
    
    /**
     * Determines whether two strings are the same.
     *
     * @param a  first string
     * @param b  second string
     *
     * @return  true if the two strings are equal; false otherwise
     */

    static public boolean isEqual(String a, String b) 
    {
        if (a == null) 
	{
            return (b == null);
        } else {
            return a.equals(b);
        }
    }

    /**
     * Determines whether two PasswordCredentials are the same.
     *
     * @param a  first PasswordCredential
     * @param b  second PasswordCredential
     *
     * @return  true if the two parameters are equal; false otherwise
     */

    static public boolean isPasswordCredentialEqual(PasswordCredential a,
                                                    PasswordCredential b) 
    {
        if (a == b) 
	    return true;
        if ((a == null) && (b != null)) 
	    return false;
        if ((a != null) && (b == null)) 
	    return false;
        if (!isEqual(a.getUserName(), b.getUserName())) 
	    return false;

        String p1 = null;
        String p2 = null;

        if (a.getPassword() != null) 
	{
            p1 = new String(a.getPassword());
        }
        if (b.getPassword() != null) 
	{
            p2 = new String(b.getPassword());
        }
        return (isEqual(p1, p2));
    }
}