/*
 * Ported from Flashlight VNC ActionScript implementation:
 *     http://www.wizhelp.com/flashlight-vnc/
 *
 * Full attribution follows:
 *
 * -------------------------------------------------------------------------
 *
 * 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/
 */

"use strict";
/*jslint white: false, bitwise: false, plusplus: false */

var DES = {

    // Tables, permutations, S-boxes, etc.
    bytebit : [0x01,0x02,0x04,0x08,0x10,0x20,0x40,0x80],
    bigbyte : [ 0x800000, 0x400000, 0x200000, 0x100000,
        0x080000, 0x040000, 0x020000, 0x010000, 0x008000, 0x004000,
        0x002000, 0x001000, 0x000800, 0x000400, 0x000200, 0x000100,
        0x000080, 0x000040, 0x000020, 0x000010, 0x000008, 0x000004,
        0x000002, 0x000001],
    pc1 : [56,48,40,32,24,16, 8, 0,57,49,41,33,25,17, 9, 1,
           58,50,42,34,26,18,10, 2,59,51,43,35,62,54,46,38,
           30,22,14,6, 61,53,45,37,29,21,13, 5,60,52,44,36,
           28,20,12, 4,27,19,11, 3],
    pc2 : [13,16,10,23, 0, 4, 2,27,14, 5,20, 9,22,18,11, 3,
           25, 7,15, 6,26,19,12, 1,40,51,30,36,46,54,29,39,
           50,44,32,47,43,48,38,55,33,52,45,41,49,35,28,31 ],
    totrot : [ 1, 2, 4, 6, 8,10,12,14,15,17,19,21,23,25,27,28],
    SP1 : [ 0x01010400, 0x00000000, 0x00010000,
        0x01010404, 0x01010004, 0x00010404, 0x00000004, 0x00010000,
        0x00000400, 0x01010400, 0x01010404, 0x00000400, 0x01000404,
        0x01010004, 0x01000000, 0x00000004, 0x00000404, 0x01000400,
        0x01000400, 0x00010400, 0x00010400, 0x01010000, 0x01010000,
        0x01000404, 0x00010004, 0x01000004, 0x01000004, 0x00010004,
        0x00000000, 0x00000404, 0x00010404, 0x01000000, 0x00010000,
        0x01010404, 0x00000004, 0x01010000, 0x01010400, 0x01000000,
        0x01000000, 0x00000400, 0x01010004, 0x00010000, 0x00010400,
        0x01000004, 0x00000400, 0x00000004, 0x01000404, 0x00010404,
        0x01010404, 0x00010004, 0x01010000, 0x01000404, 0x01000004,
        0x00000404, 0x00010404, 0x01010400, 0x00000404, 0x01000400,
        0x01000400, 0x00000000, 0x00010004, 0x00010400, 0x00000000,
        0x01010004],
    SP2 : [ 0x80108020, 0x80008000, 0x00008000,
        0x00108020, 0x00100000, 0x00000020, 0x80100020, 0x80008020,
        0x80000020, 0x80108020, 0x80108000, 0x80000000, 0x80008000,
        0x00100000, 0x00000020, 0x80100020, 0x00108000, 0x00100020,
        0x80008020, 0x00000000, 0x80000000, 0x00008000, 0x00108020,
        0x80100000, 0x00100020, 0x80000020, 0x00000000, 0x00108000,
        0x00008020, 0x80108000, 0x80100000, 0x00008020, 0x00000000,
        0x00108020, 0x80100020, 0x00100000, 0x80008020, 0x80100000,
        0x80108000, 0x00008000, 0x80100000, 0x80008000, 0x00000020,
        0x80108020, 0x00108020, 0x00000020, 0x00008000, 0x80000000,
        0x00008020, 0x80108000, 0x00100000, 0x80000020, 0x00100020,
        0x80008020, 0x80000020, 0x00100020, 0x00108000, 0x00000000,
        0x80008000, 0x00008020, 0x80000000, 0x80100020, 0x80108020,
        0x00108000],
    SP3 : [ 0x00000208, 0x08020200, 0x00000000,
        0x08020008, 0x08000200, 0x00000000, 0x00020208, 0x08000200,
        0x00020008, 0x08000008, 0x08000008, 0x00020000, 0x08020208,
        0x00020008, 0x08020000, 0x00000208, 0x08000000, 0x00000008,
        0x08020200, 0x00000200, 0x00020200, 0x08020000, 0x08020008,
        0x00020208, 0x08000208, 0x00020200, 0x00020000, 0x08000208,
        0x00000008, 0x08020208, 0x00000200, 0x08000000, 0x08020200,
        0x08000000, 0x00020008, 0x00000208, 0x00020000, 0x08020200,
        0x08000200, 0x00000000, 0x00000200, 0x00020008, 0x08020208,
        0x08000200, 0x08000008, 0x00000200, 0x00000000, 0x08020008,
        0x08000208, 0x00020000, 0x08000000, 0x08020208, 0x00000008,
        0x00020208, 0x00020200, 0x08000008, 0x08020000, 0x08000208,
        0x00000208, 0x08020000, 0x00020208, 0x00000008, 0x08020008,
        0x00020200],
    SP4 : [ 0x00802001, 0x00002081, 0x00002081,
        0x00000080, 0x00802080, 0x00800081, 0x00800001, 0x00002001,
        0x00000000, 0x00802000, 0x00802000, 0x00802081, 0x00000081,
        0x00000000, 0x00800080, 0x00800001, 0x00000001, 0x00002000,
        0x00800000, 0x00802001, 0x00000080, 0x00800000, 0x00002001,
        0x00002080, 0x00800081, 0x00000001, 0x00002080, 0x00800080,
        0x00002000, 0x00802080, 0x00802081, 0x00000081, 0x00800080,
        0x00800001, 0x00802000, 0x00802081, 0x00000081, 0x00000000,
        0x00000000, 0x00802000, 0x00002080, 0x00800080, 0x00800081,
        0x00000001, 0x00802001, 0x00002081, 0x00002081, 0x00000080,
        0x00802081, 0x00000081, 0x00000001, 0x00002000, 0x00800001,
        0x00002001, 0x00802080, 0x00800081, 0x00002001, 0x00002080,
        0x00800000, 0x00802001, 0x00000080, 0x00800000, 0x00002000,
        0x00802080],
    SP5 : [ 0x00000100, 0x02080100, 0x02080000,
        0x42000100, 0x00080000, 0x00000100, 0x40000000, 0x02080000,
        0x40080100, 0x00080000, 0x02000100, 0x40080100, 0x42000100,
        0x42080000, 0x00080100, 0x40000000, 0x02000000, 0x40080000,
        0x40080000, 0x00000000, 0x40000100, 0x42080100, 0x42080100,
        0x02000100, 0x42080000, 0x40000100, 0x00000000, 0x42000000,
        0x02080100, 0x02000000, 0x42000000, 0x00080100, 0x00080000,
        0x42000100, 0x00000100, 0x02000000, 0x40000000, 0x02080000,
        0x42000100, 0x40080100, 0x02000100, 0x40000000, 0x42080000,
        0x02080100, 0x40080100, 0x00000100, 0x02000000, 0x42080000,
        0x42080100, 0x00080100, 0x42000000, 0x42080100, 0x02080000,
        0x00000000, 0x40080000, 0x42000000, 0x00080100, 0x02000100,
        0x40000100, 0x00080000, 0x00000000, 0x40080000, 0x02080100,
        0x40000100],
    SP6 : [ 0x20000010, 0x20400000, 0x00004000,
        0x20404010, 0x20400000, 0x00000010, 0x20404010, 0x00400000,
        0x20004000, 0x00404010, 0x00400000, 0x20000010, 0x00400010,
        0x20004000, 0x20000000, 0x00004010, 0x00000000, 0x00400010,
        0x20004010, 0x00004000, 0x00404000, 0x20004010, 0x00000010,
        0x20400010, 0x20400010, 0x00000000, 0x00404010, 0x20404000,
        0x00004010, 0x00404000, 0x20404000, 0x20000000, 0x20004000,
        0x00000010, 0x20400010, 0x00404000, 0x20404010, 0x00400000,
        0x00004010, 0x20000010, 0x00400000, 0x20004000, 0x20000000,
        0x00004010, 0x20000010, 0x20404010, 0x00404000, 0x20400000,
        0x00404010, 0x20404000, 0x00000000, 0x20400010, 0x00000010,
        0x00004000, 0x20400000, 0x00404010, 0x00004000, 0x00400010,
        0x20004010, 0x00000000, 0x20404000, 0x20000000, 0x00400010,
        0x20004010],
    SP7 : [ 0x00200000, 0x04200002, 0x04000802,
        0x00000000, 0x00000800, 0x04000802, 0x00200802, 0x04200800,
        0x04200802, 0x00200000, 0x00000000, 0x04000002, 0x00000002,
        0x04000000, 0x04200002, 0x00000802, 0x04000800, 0x00200802,
        0x00200002, 0x04000800, 0x04000002, 0x04200000, 0x04200800,
        0x00200002, 0x04200000, 0x00000800, 0x00000802, 0x04200802,
        0x00200800, 0x00000002, 0x04000000, 0x00200800, 0x04000000,
        0x00200800, 0x00200000, 0x04000802, 0x04000802, 0x04200002,
        0x04200002, 0x00000002, 0x00200002, 0x04000000, 0x04000800,
        0x00200000, 0x04200800, 0x00000802, 0x00200802, 0x04200800,
        0x00000802, 0x04000002, 0x04200802, 0x04200000, 0x00200800,
        0x00000000, 0x00000002, 0x04200802, 0x00000000, 0x00200802,
        0x04200000, 0x00000800, 0x04000002, 0x04000800, 0x00000800,
        0x00200002],
    SP8 : [ 0x10001040, 0x00001000, 0x00040000,
        0x10041040, 0x10000000, 0x10001040, 0x00000040, 0x10000000,
        0x00040040, 0x10040000, 0x10041040, 0x00041000, 0x10041000,
        0x00041040, 0x00001000, 0x00000040, 0x10040000, 0x10000040,
        0x10001000, 0x00001040, 0x00041000, 0x00040040, 0x10040040,
        0x10041000, 0x00001040, 0x00000000, 0x00000000, 0x10040040,
        0x10000040, 0x10001000, 0x00041040, 0x00040000, 0x00041040,
        0x00040000, 0x10041000, 0x00001000, 0x00000040, 0x10040040,
        0x00001000, 0x00041040, 0x10001000, 0x00000040, 0x10000040,
        0x10040000, 0x10040040, 0x10000000, 0x00040000, 0x10001040,
        0x00000000, 0x10041040, 0x00040040, 0x10000040, 0x10040000,
        0x10001000, 0x10001040, 0x00000000, 0x10041040, 0x00041000,
        0x00041000, 0x00001040, 0x00001040, 0x00040040, 0x10000000,
        0x10041000],

    keys : [],

    // Set the key.
    setKeys : function(keyBlock) {
        var i, j, l, m, n, pc1m = [], pcr = [], kn = [],
            raw0, raw1, rawi, KnLi;

        for (j = 0; j < 56; ++j) {
            l = DES.pc1[j];
            m = l & 0x7;
            pc1m[j] = ((keyBlock[l >>> 3] & DES.bytebit[m]) !== 0) ? 1: 0;
        }

        for (i = 0; i < 16; ++i) {
            m = i << 1;
            n = m + 1;
            kn[m] = kn[n] = 0;
            for (j = 0; j < 28; ++j) {
                l = j + DES.totrot[i];
                if (l < 28) {
                    pcr[j] = pc1m[l];
                } else {
                    pcr[j] = pc1m[l - 28];
                }
            }
            for (j = 28; j < 56; ++j) {
                l = j + DES.totrot[i];
                if (l < 56) {
                    pcr[j] = pc1m[l];
                } else {
                    pcr[j] = pc1m[l - 28];
                }
            }
            for (j = 0; j < 24; ++j) {
                if (pcr[DES.pc2[j]] !== 0) {
                    kn[m] |= DES.bigbyte[j];
                }
                if (pcr[DES.pc2[j + 24]] !== 0) {
                    kn[n] |= DES.bigbyte[j];
                }
            }
        }

        // cookey
        for (i = 0, rawi = 0, KnLi = 0; i < 16; ++i) {
            raw0 = kn[rawi++];
            raw1 = kn[rawi++];
            DES.keys[KnLi] = (raw0 & 0x00fc0000) << 6;
            DES.keys[KnLi] |= (raw0 & 0x00000fc0) << 10;
            DES.keys[KnLi] |= (raw1 & 0x00fc0000) >>> 10;
            DES.keys[KnLi] |= (raw1 & 0x00000fc0) >>> 6;
            ++KnLi;
            DES.keys[KnLi] = (raw0 & 0x0003f000) << 12;
            DES.keys[KnLi] |= (raw0 & 0x0000003f) << 16;
            DES.keys[KnLi] |= (raw1 & 0x0003f000) >>> 4;
            DES.keys[KnLi] |= (raw1 & 0x0000003f);
            ++KnLi;
        }
    },

    // Encrypt 8 bytes of text starting at offset
    encrypt8: function(text, offset) {
        var i, b = text, o, outInts =[],
            fval, work, right, leftt, round, keysi = 0;

        // Squash 8 bytes down to 2 ints
        o = offset;
        leftt = b[o++]<<24 | b[o++]<<16 | b[o++]<<8 | b[o++];
        right = b[o++]<<24 | b[o++]<<16 | b[o++]<<8 | b[o++];

        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 ^= DES.keys[keysi++];
            fval =  DES.SP7[work & 0x0000003f];
            fval |= DES.SP5[(work >>> 8) & 0x0000003f];
            fval |= DES.SP3[(work >>> 16) & 0x0000003f];
            fval |= DES.SP1[(work >>> 24) & 0x0000003f];
            work = right ^ DES.keys[keysi++];
            fval |= DES.SP8[work & 0x0000003f];
            fval |= DES.SP6[(work >>> 8) & 0x0000003f];
            fval |= DES.SP4[(work >>> 16) & 0x0000003f];
            fval |= DES.SP2[(work >>> 24) & 0x0000003f];
            leftt ^= fval;
            work = (leftt << 28) | (leftt >>> 4);
            work ^= DES.keys[keysi++];
            fval =  DES.SP7[work & 0x0000003f];
            fval |= DES.SP5[(work >>> 8) & 0x0000003f];
            fval |= DES.SP3[(work >>> 16) & 0x0000003f];
            fval |= DES.SP1[(work >>> 24) & 0x0000003f];
            work = leftt ^ DES.keys[keysi++];
            fval |= DES.SP8[work & 0x0000003f];
            fval |= DES.SP6[(work >>> 8) & 0x0000003f];
            fval |= DES.SP4[(work >>> 16) & 0x0000003f];
            fval |= DES.SP2[(work >>> 24) & 0x0000003f];
            right ^= fval;
        }

        right = (right << 31) | (right >>> 1);
        work = (leftt ^ right) & 0xaaaaaaaa;
        leftt ^= work;
        right ^= work;
        leftt = (leftt << 31) | (leftt >>> 1);
        work = ((leftt >>> 8) ^ right) & 0x00ff00ff;
        right ^= work;
        leftt ^= (work << 8);
        work = ((leftt >>> 2) ^ right) & 0x33333333;
        right ^= work;
        leftt ^= (work << 2);
        work = ((right >>> 16) ^ leftt) & 0x0000ffff;
        leftt ^= work;
        right ^= (work << 16);
        work = ((right >>> 4) ^ leftt) & 0x0f0f0f0f;
        leftt ^= work;
        right ^= (work << 4);
        outInts[0] = right;
        outInts[1] = leftt;

        // Spread ints to bytes
        o = offset;
        for (i = 0; i < 8; i++) {
            b[o+i] = (outInts[i>>>2] >>> (8*(3 - (i%4)))) % 256;
            if (b[o+i] < 0) { b[o+i] += 256; } // unsigned
        }
    },

    // Encrypt 16 bytes of text using passwd as key
    encrypt: function(passwd, text) {
        var i, cipher = text.slice();
        DES.setKeys(passwd);
        DES.encrypt8(cipher, 0);
        DES.encrypt8(cipher, 8);
        return cipher;
    }
};