//// This DES class has been extracted from package Acme.Crypto for use in VNC.// The bytebit[] array has been reversed so that the most significant bit// in each byte of the key is ignored, not the least significant.  Also the// unnecessary odd parity code has been removed.//// These changes are://  Copyright (C) 1999 AT&T Laboratories Cambridge.  All Rights Reserved.//// This software 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.//// DesCipher - the DES encryption method//// The meat of this code is by Dave Zimmerman <dzimm@widget.com>, and is://// Copyright (c) 1996 Widget Workshop, Inc. All Rights Reserved.//// Permission to use, copy, modify, and distribute this software// and its documentation for NON-COMMERCIAL or COMMERCIAL purposes and// without fee is hereby granted, provided that this copyright notice is kept // intact. // // WIDGET WORKSHOP MAKES NO REPRESENTATIONS OR WARRANTIES ABOUT THE SUITABILITY// OF THE SOFTWARE, EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED// TO THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A// PARTICULAR PURPOSE, OR NON-INFRINGEMENT. WIDGET WORKSHOP SHALL NOT BE LIABLE// FOR ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF USING, MODIFYING OR// DISTRIBUTING THIS SOFTWARE OR ITS DERIVATIVES.// // THIS SOFTWARE IS NOT DESIGNED OR INTENDED FOR USE OR RESALE AS ON-LINE// CONTROL EQUIPMENT IN HAZARDOUS ENVIRONMENTS REQUIRING FAIL-SAFE// PERFORMANCE, SUCH AS IN THE OPERATION OF NUCLEAR FACILITIES, AIRCRAFT// NAVIGATION OR COMMUNICATION SYSTEMS, AIR TRAFFIC CONTROL, DIRECT LIFE// SUPPORT MACHINES, OR WEAPONS SYSTEMS, IN WHICH THE FAILURE OF THE// SOFTWARE COULD LEAD DIRECTLY TO DEATH, PERSONAL INJURY, OR SEVERE// PHYSICAL OR ENVIRONMENTAL DAMAGE ("HIGH RISK ACTIVITIES").  WIDGET WORKSHOP// SPECIFICALLY DISCLAIMS ANY EXPRESS OR IMPLIED WARRANTY OF FITNESS FOR// HIGH RISK ACTIVITIES.////// The rest is://// Copyright (C) 1996 by Jef Poskanzer <jef@acme.com>.  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.//// THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND// ANY EXPRESS 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 AUTHOR OR 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.//// Visit the ACME Labs Java page for up-to-date versions of this and other// fine Java utilities: http://www.acme.com/java/import java.io.*;/// The DES encryption method.// <P>// This is surprisingly fast, for pure Java.  On a SPARC 20, wrapped// in Acme.Crypto.EncryptedOutputStream or Acme.Crypto.EncryptedInputStream,// it does around 7000 bytes/second.// <P>// Most of this code is by Dave Zimmerman <dzimm@widget.com>, and is// Copyright (c) 1996 Widget Workshop, Inc.  See the source file for details.// <P>// <A HREF="/resources/classes/Acme/Crypto/DesCipher.java">Fetch the software.</A><BR>// <A HREF="/resources/classes/Acme.tar.Z">Fetch the entire Acme package.</A>// <P>// @see Des3Cipher// @see EncryptedOutputStream// @see EncryptedInputStreampublic class DesCipher    {    // Constructor, byte-array key.    public DesCipher( byte[] key )	{	setKey( key );	}    // Key routines.    private int[] encryptKeys = new int[32];    private int[] decryptKeys = new int[32];    /// Set the key.    public void setKey( byte[] key )	{	deskey( key, true, encryptKeys );	deskey( key, false, decryptKeys );	}    // Turn an 8-byte key into internal keys.    private void deskey( byte[] keyBlock, boolean encrypting, int[] KnL )	{	int i, j, l, m, n;	int[] pc1m = new int[56];	int[] pcr = new int[56];	int[] kn = new int[32];	for ( j = 0; j < 56; ++j )	    {	    l = pc1[j];	    m = l & 07;	    pc1m[j] = ( (keyBlock[l >>> 3] & bytebit[m]) != 0 )? 1: 0;	    }	for ( i = 0; i < 16; ++i )	    {	    if ( encrypting )		m = i << 1;	    else		m = (15-i) << 1;	    n = m+1;	    kn[m] = kn[n] = 0;	    for ( j = 0; j < 28; ++j )		{		l = j+totrot[i];		if ( l < 28 )		    pcr[j] = pc1m[l];		else		    pcr[j] = pc1m[l-28];		}	    for ( j=28; j < 56; ++j )		{		l = j+totrot[i];		if ( l < 56 )		    pcr[j] = pc1m[l];		else		    pcr[j] = pc1m[l-28];		}	    for ( j = 0; j < 24; ++j )		{		if ( pcr[pc2[j]] != 0 )		    kn[m] |= bigbyte[j];		if ( pcr[pc2[j+24]] != 0 )		    kn[n] |= bigbyte[j];		}	    }	cookey( kn, KnL );	}    private void cookey( int[] raw, int KnL[] )	{	int raw0, raw1;	int rawi, KnLi;	int i;	for ( i = 0, rawi = 0, KnLi = 0; i < 16; ++i )	    {	    raw0 = raw[rawi++];	    raw1 = raw[rawi++];	    KnL[KnLi]  = (raw0 & 0x00fc0000) <<   6;	    KnL[KnLi] |= (raw0 & 0x00000fc0) <<  10;	    KnL[KnLi] |= (raw1 & 0x00fc0000) >>> 10;	    KnL[KnLi] |= (raw1 & 0x00000fc0) >>>  6;	    ++KnLi;	    KnL[KnLi]  = (raw0 & 0x0003f000) <<  12;	    KnL[KnLi] |= (raw0 & 0x0000003f) <<  16;	    KnL[KnLi] |= (raw1 & 0x0003f000) >>>  4;	    KnL[KnLi] |= (raw1 & 0x0000003f);	    ++KnLi;	    }	}    // Block encryption routines.    private int[] tempInts = new int[2];    /// Encrypt a block of eight bytes.    public void encrypt( byte[] clearText, int clearOff, byte[] cipherText, int cipherOff )	{	squashBytesToInts( clearText, clearOff, tempInts, 0, 2 );	des( tempInts, tempInts, encryptKeys );	spreadIntsToBytes( tempInts, 0, cipherText, cipherOff, 2 );	}    /// Decrypt a block of eight bytes.    public void decrypt( byte[] cipherText, int cipherOff, byte[] clearText, int clearOff )	{	squashBytesToInts( cipherText, cipherOff, tempInts, 0, 2 );	des( tempInts, tempInts, decryptKeys );	spreadIntsToBytes( tempInts, 0, clearText, clearOff, 2 );	}    // The DES function.    private void des( int[] inInts, int[] outInts, int[] keys )	{	int fval, work, right, leftt;	int round;	int keysi = 0;	leftt = inInts[0];	right = inInts[1];	work   = ((leftt >>>  4) ^ right) & 0x0f0f0f0f;	right ^= work;	leftt ^= (work << 4);	work   = ((leftt >>> 16) ^ right) & 0x0000ffff;	right ^= work;	leftt ^= (work << 16);	work   = ((right >>>  2) ^ leftt) & 0x33333333;	leftt ^= work;	right ^= (work << 2);	work   = ((right >>>  8) ^ leftt) & 0x00ff00ff;	leftt ^= work;	right ^= (work << 8);	right  = (right << 1) | ((right >>> 31) & 1);	work   = (leftt ^ right) & 0xaaaaaaaa;	leftt ^= work;	right ^= work;	leftt  = (leftt << 1) | ((leftt >>> 31) & 1);	for ( round = 0; round < 8; ++round )	    {	    work   = (right << 28) | (right >>> 4);	    work  ^= keys[keysi++];	    fval   = SP7[ work	       & 0x0000003f ];	    fval  |= SP5[(work >>>  8) & 0x0000003f ];	    fval  |= SP3[(work >>> 16) & 0x0000003f ];	    fval  |= SP1[(work >>> 24) & 0x0000003f ];	    work   = right ^ keys[keysi++];	    fval  |= SP8[ work         & 0x0000003f ];	    fval  |= SP6[(work >>>  8) & 0x0000003f ];	    fval  |= SP4[(work >>> 16) & 0x0000003f ];