/**
 * DESKey
 * 
 * An Actionscript 3 implementation of the Data Encryption Standard (DES)
 * Copyright (c) 2007 Henri Torgemane
 * 
 * Derived from:
 *         The Bouncy Castle Crypto package, 
 *         Copyright (c) 2000-2004 The Legion Of The Bouncy Castle
 *         (http://www.bouncycastle.org)
 * 
 * See LICENSE.txt for full license information.
 */
package com.hurlant.crypto.symmetric
{
    import flash.utils.ByteArray;
    import com.hurlant.util.Hex;
    import com.hurlant.util.Memory;

    public class DESKey implements ISymmetricKey
    {
        /**
         * what follows is mainly taken from "Applied Cryptography", by Bruce
         * Schneier, however it also bears great resemblance to Richard
         * Outerbridge's D3DES...
         */
    
        private static const Df_Key:Array = [ 0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef, 0xfe, 0xdc, 0xba, 0x98, 0x76, 0x54, 0x32,
                0x10, 0x89, 0xab, 0xcd, 0xef, 0x01, 0x23, 0x45, 0x67 ];
    
        private static const bytebit:Array = [ 128, 64, 32, 16, 8, 4, 2, 1 ];
    
        private static const bigbyte:Array = [ 0x800000, 0x400000, 0x200000, 0x100000, 0x80000, 0x40000, 0x20000, 0x10000, 0x8000,
                0x4000, 0x2000, 0x1000, 0x800, 0x400, 0x200, 0x100, 0x80, 0x40, 0x20, 0x10, 0x8, 0x4, 0x2, 0x1 ];
    
        /*
         * Use the key schedule specified in the Standard (ANSI X3.92-1981).
         */
    
        private static const pc1:Array = [ 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 ];
    
        private static const totrot:Array = [ 1, 2, 4, 6, 8, 10, 12, 14, 15, 17, 19, 21, 23, 25, 27, 28 ];
    
        private static const pc2:Array = [ 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 ];
    
        private static const SP1:Array = [ 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 ];
    
        private static const SP2:Array = [ 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 ];
    
        private static const SP3:Array = [ 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 ];
    
        private static const SP4:Array = [ 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 ];
    
        private static const SP5:Array = [ 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 ];
    
        private static const SP6:Array = [ 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 ];
    
        private static const SP7:Array = [ 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 ];
    
        private static const SP8:Array = [ 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 ];

    
        protected var key:ByteArray;
        protected var encKey:Array;
        protected var decKey:Array;
    

        public function DESKey(key:ByteArray) {
            this.key = key;
            this.encKey = generateWorkingKey(true, key, 0);
            this.decKey = generateWorkingKey(false, key, 0);
        }

        public function getBlockSize():uint
        {
            return 8;
        }
        
        public function decrypt(block:ByteArray, index:uint=0):void
        {
            desFunc(decKey, block, index, block, index);
        }
        
        public function dispose():void
        {
            var i:uint=0;
            for (i=0;i<encKey.length;i++) { encKey[i]=0; }
            for (i=0;i<decKey.length;i++) { decKey[i]=0; }
            encKey=null;
            decKey=null;
            for (i=0;i<key.length;i++) { key[i]=0; }
            key.length = 0;
            key = null;
            Memory.gc();
        }
        
        public function encrypt(block:ByteArray, index:uint=0):void
        {
            desFunc(encKey, block, index, block, index);
        }
            
    
        /**
         * generate an integer based working key based on our secret key and what we
         * processing we are planning to do.
         * 
         * Acknowledgements for this routine go to James Gillogly & Phil Karn.
         */
        protected function generateWorkingKey(encrypting:Boolean, key:ByteArray, off:uint):Array
        {
            //int[] newKey = new int[32];
            var newKey:Array = [];
            //boolean[] pc1m = new boolean[56], pcr = new boolean[56];
            var pc1m:ByteArray = new ByteArray;
            var pcr:ByteArray = new ByteArray;
            
            var l:uint;
    
            for (var j:uint = 0; j < 56; j++)
            {
                l = pc1[j];
    
                pc1m[j] = ((key[off + (l >>> 3)] & bytebit[l & 07]) != 0);
            }
    
            for (var i:uint = 0; i < 16; i++)
            {
                var m:uint;
                var n:uint;
    
                if (encrypting)
                {
                    m = i << 1;
                }
                else
                {
                    m = (15 - i) << 1;
                }
    
                n = m + 1;
                newKey[m] = newKey[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]])
                    {
                        newKey[m] |= bigbyte[j];
                    }
    
                    if (pcr[pc2[j + 24]])
                    {
                        newKey[n] |= bigbyte[j];
                    }
                }
            }
    
            //
            // store the processed key
            //
            for (i = 0; i != 32; i += 2)
            {
                var i1:uint;
                var i2:uint;
    
                i1 = newKey[i];
                i2 = newKey[i + 1];
    
                newKey[i] = ((i1 & 0x00fc0000) << 6) | ((i1 & 0x00000fc0) << 10) | ((i2 & 0x00fc0000) >>> 10)
                        | ((i2 & 0x00000fc0) >>> 6);
    
                newKey[i + 1] = ((i1 & 0x0003f000) << 12) | ((i1 & 0x0000003f) << 16) | ((i2 & 0x0003f000) >>> 4)
                        | (i2 & 0x0000003f);
            }
            return newKey;
        }
    
        /**
         * the DES engine.
         */
        protected function desFunc(wKey:Array, inp:ByteArray, inOff:uint, out:ByteArray, outOff:uint):void
        {
            var work:uint;
            var right:uint;
            var left:uint;
    
            left = (inp[inOff + 0] & 0xff) << 24;
            left |= (inp[inOff + 1] & 0xff) << 16;
            left |= (inp[inOff + 2] & 0xff) << 8;
            left |= (inp[inOff + 3] & 0xff);
    
            right = (inp[inOff + 4] & 0xff) << 24;
            right |= (inp[inOff + 5] & 0xff) << 16;
            right |= (inp[inOff + 6] & 0xff) << 8;
            right |= (inp[inOff + 7] & 0xff);

            work = ((left >>> 4) ^ right) & 0x0f0f0f0f;
            right ^= work;
            left ^= (work << 4);
            work = ((left >>> 16) ^ right) & 0x0000ffff;
            right ^= work;
            left ^= (work << 16);
            work = ((right >>> 2) ^ left) & 0x33333333;
            left ^= work;
            right ^= (work << 2);
            work = ((right >>> 8) ^ left) & 0x00ff00ff;
            left ^= work;
            right ^= (work << 8);
            right = ((right << 1) | ((right >>> 31) & 1)) & 0xffffffff;
            work = (left ^ right) & 0xaaaaaaaa;
            left ^= work;
            right ^= work;
            left = ((left << 1) | ((left >>> 31) & 1)) & 0xffffffff;

            for (var round:uint = 0; round < 8; round++)
            {
                var fval:uint;
    
                work = (right << 28) | (right >>> 4);
                work ^= wKey[round * 4 + 0];
                fval = SP7[work & 0x3f];
                fval |= SP5[(work >>> 8) & 0x3f];
                fval |= SP3[(work >>> 16) & 0x3f];
                fval |= SP1[(work >>> 24) & 0x3f];
                work = right ^ wKey[round * 4 + 1];
                fval |= SP8[work & 0x3f];
                fval |= SP6[(work >>> 8) & 0x3f];
                fval |= SP4[(work >>> 16) & 0x3f];
                fval |= SP2[(work >>> 24) & 0x3f];
                left ^= fval;
                work = (left << 28) | (left >>> 4);
                work ^= wKey[round * 4 + 2];
                fval = SP7[work & 0x3f];
                fval |= SP5[(work >>> 8) & 0x3f];
                fval |= SP3[(work >>> 16) & 0x3f];
                fval |= SP1[(work >>> 24) & 0x3f];
                work = left ^ wKey[round * 4 + 3];
                fval |= SP8[work & 0x3f];
                fval |= SP6[(work >>> 8) & 0x3f];
                fval |= SP4[(work >>> 16) & 0x3f];
                fval |= SP2[(work >>> 24) & 0x3f];
                right ^= fval;
            }
    
            right = (right << 31) | (right >>> 1);
            work = (left ^ right) & 0xaaaaaaaa;
            left ^= work;
            right ^= work;
            left = (left << 31) | (left >>> 1);
            work = ((left >>> 8) ^ right) & 0x00ff00ff;
            right ^= work;
            left ^= (work << 8);
            work = ((left >>> 2) ^ right) & 0x33333333;
            right ^= work;
            left ^= (work << 2);
            work = ((right >>> 16) ^ left) & 0x0000ffff;
            left ^= work;
            right ^= (work << 16);
            work = ((right >>> 4) ^ left) & 0x0f0f0f0f;
            left ^= work;
            right ^= (work << 4);
    
            out[outOff + 0] = ((right >>> 24) & 0xff);
            out[outOff + 1] = ((right >>> 16) & 0xff);
            out[outOff + 2] = ((right >>> 8) & 0xff);
            out[outOff + 3] = (right & 0xff);
            out[outOff + 4] = ((left >>> 24) & 0xff);
            out[outOff + 5] = ((left >>> 16) & 0xff);
            out[outOff + 6] = ((left >>> 8) & 0xff);
            out[outOff + 7] = (left & 0xff);
        }
        
        
        public function toString():String {
            return "des";
        }
        
        
        
    }
}