///////////////////////////////////////////////////////////////////////////////
                         //Des DEMO V1.0//
                          //作者：ksaiy//
//歡迎使用由ksaiy制作的DES加密算法演示程序，此算法為標(biāo)準(zhǔn)的DES算法，你可以根據(jù)的
//的自己需要進(jìn)行變形。具體怎么操作可以登錄我們的網(wǎng)站查詢詳細(xì)的資料。我們專門為軟
//件開發(fā)者提供軟件加密安全測試服務(wù)和軟件加密解決方案，具體的可以參看我們的網(wǎng)站上
//的資料。我們的網(wǎng)站：http://www.ksaiy.com  http://www.magicoa.com
//技術(shù)支持:ksaiy@sina.com 在線QQ：40188696 UC：934155
                            //End //

                  //注意：轉(zhuǎn)載請保留以上信息。//                            
///////////////////////////////////////////////////////////////////////////////
unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls;

type
  TForm1 = class(TForm)
    Label1: TLabel;
    Label2: TLabel;
    Edit1: TEdit;
    Edit2: TEdit;
    Button1: TButton;
    Button2: TButton;
    Label3: TLabel;
    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

type
  TKeyByte = array[0..5] of Byte;
  TDesMode = (dmEncry, dmDecry);

  function EncryStr(Str, Key: String): String;
  function DecryStr(Str, Key: String): String;
  function EncryStrHex(Str, Key: String): String;
  function DecryStrHex(StrHex, Key: String): String;
  
const
  BitIP: array[0..63] of Byte =   //初始值置IP
    (57, 49, 41, 33, 25, 17,  9,  1,
     59, 51, 43, 35, 27, 19, 11,  3,
     61, 53, 45, 37, 29, 21, 13,  5,
     63, 55, 47, 39, 31, 23, 15,  7,
     56, 48, 40, 32, 24, 16,  8,  0,
     58, 50, 42, 34, 26, 18, 10,  2,
     60, 52, 44, 36, 28, 20, 12,  4,
     62, 54, 46, 38, 30, 22, 14,  6 );

  BitCP: array[0..63] of Byte = //逆初始置IP-1
    ( 39,  7, 47, 15, 55, 23, 63, 31,
      38,  6, 46, 14, 54, 22, 62, 30,
      37,  5, 45, 13, 53, 21, 61, 29,
      36,  4, 44, 12, 52, 20, 60, 28,
      35,  3, 43, 11, 51, 19, 59, 27,
      34,  2, 42, 10, 50, 18, 58, 26,
      33,  1, 41,  9, 49, 17, 57, 25,
      32,  0, 40,  8, 48, 16, 56, 24 );

  BitExp: array[0..47] of Integer = // 位選擇函數(shù)E
    ( 31, 0, 1, 2, 3, 4, 3, 4, 5, 6, 7, 8, 7, 8, 9,10,
      11,12,11,12,13,14,15,16,15,16,17,18,19,20,19,20,
      21,22,23,24,23,24,25,26,27,28,27,28,29,30,31,0  );

  BitPM: array[0..31] of Byte =  //置換函數(shù)P
    ( 15, 6,19,20,28,11,27,16, 0,14,22,25, 4,17,30, 9,
       1, 7,23,13,31,26, 2, 8,18,12,29, 5,21,10, 3,24 );

  sBox: array[0..7] of array[0..63] of Byte =    //S盒
    ( ( 14,  4, 13,  1,  2, 15, 11,  8,  3, 10,  6, 12,  5,  9,  0,  7,
         0, 15,  7,  4, 14,  2, 13,  1, 10,  6, 12, 11,  9,  5,  3,  8,
         4,  1, 14,  8, 13,  6,  2, 11, 15, 12,  9,  7,  3, 10,  5,  0,
        15, 12,  8,  2,  4,  9,  1,  7,  5, 11,  3, 14, 10,  0,  6, 13 ),

      ( 15,  1,  8, 14,  6, 11,  3,  4,  9,  7,  2, 13, 12,  0,  5, 10,
         3, 13,  4,  7, 15,  2,  8, 14, 12,  0,  1, 10,  6,  9, 11,  5,
         0, 14,  7, 11, 10,  4, 13,  1,  5,  8, 12,  6,  9,  3,  2, 15,
        13,  8, 10,  1,  3, 15,  4,  2, 11,  6,  7, 12,  0,  5, 14,  9 ),

      ( 10,  0,  9, 14,  6,  3, 15,  5,  1, 13, 12,  7, 11,  4,  2,  8,
        13,  7,  0,  9,  3,  4,  6, 10,  2,  8,  5, 14, 12, 11, 15,  1,
        13,  6,  4,  9,  8, 15,  3,  0, 11,  1,  2, 12,  5, 10, 14,  7,
         1, 10, 13,  0,  6,  9,  8,  7,  4, 15, 14,  3, 11,  5,  2, 12 ),

      (  7, 13, 14,  3,  0,  6,  9, 10,  1,  2,  8,  5, 11, 12,  4, 15,
        13,  8, 11,  5,  6, 15,  0,  3,  4,  7,  2, 12,  1, 10, 14,  9,
        10,  6,  9,  0, 12, 11,  7, 13, 15,  1,  3, 14,  5,  2,  8,  4,
         3, 15,  0,  6, 10,  1, 13,  8,  9,  4,  5, 11, 12,  7,  2, 14 ),

      (  2, 12,  4,  1,  7, 10, 11,  6,  8,  5,  3, 15, 13,  0, 14,  9,
        14, 11,  2, 12,  4,  7, 13,  1,  5,  0, 15, 10,  3,  9,  8,  6,
         4,  2,  1, 11, 10, 13,  7,  8, 15,  9, 12,  5,  6,  3,  0, 14,
        11,  8, 12,  7,  1, 14,  2, 13,  6, 15,  0,  9, 10,  4,  5,  3 ),

      ( 12,  1, 10, 15,  9,  2,  6,  8,  0, 13,  3,  4, 14,  7,  5, 11,
        10, 15,  4,  2,  7, 12,  9,  5,  6,  1, 13, 14,  0, 11,  3,  8,
         9, 14, 15,  5,  2,  8, 12,  3,  7,  0,  4, 10,  1, 13, 11,  6,
         4,  3,  2, 12,  9,  5, 15, 10, 11, 14,  1,  7,  6,  0,  8, 13 ),

      (  4, 11,  2, 14, 15,  0,  8, 13,  3, 12,  9,  7,  5, 10,  6,  1,
        13,  0, 11,  7,  4,  9,  1, 10, 14,  3,  5, 12,  2, 15,  8,  6,
         1,  4, 11, 13, 12,  3,  7, 14, 10, 15,  6,  8,  0,  5,  9,  2,
         6, 11, 13,  8,  1,  4, 10,  7,  9,  5,  0, 15, 14,  2,  3, 12 ),

      ( 13,  2,  8,  4,  6, 15, 11,  1, 10,  9,  3, 14,  5,  0, 12,  7,
         1, 15, 13,  8, 10,  3,  7,  4, 12,  5,  6, 11,  0, 14,  9,  2,
         7, 11,  4,  1,  9, 12, 14,  2,  0,  6, 10, 13, 15,  3,  5,  8,
         2,  1, 14,  7,  4, 10,  8, 13, 15, 12,  9,  0,  3,  5,  6, 11 ) );

  BitPMC1: array[0..55] of Byte = //選擇置換PC-1
    ( 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 );

  BitPMC2: array[0..47] of Byte =//選擇置換PC-2 
    ( 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 );

var
  Form1: TForm1;
  subKey: array[0..15] of TKeyByte;  

implementation

{$R *.dfm}

procedure initPermutation(var inData: array of Byte);
var
  newData: array[0..7] of Byte;
  i: Integer;
begin
  FillChar(newData, 8, 0);
  for i := 0 to 63 do
    if (inData[BitIP[i] shr 3] and (1 shl (7- (BitIP[i] and $07)))) <> 0 then
      newData[i shr 3] := newData[i shr 3] or (1 shl (7-(i and $07)));
  for i := 0 to 7 do inData[i] := newData[i];
end;

procedure conversePermutation(var inData: array of Byte);
var
  newData: array[0..7] of Byte;
  i: Integer;
begin
  FillChar(newData, 8, 0);
  for i := 0 to 63 do
    if (inData[BitCP[i] shr 3] and (1 shl (7-(BitCP[i] and $07)))) <> 0 then
      newData[i shr 3] := newData[i shr 3] or (1 shl (7-(i and $07)));
  for i := 0 to 7 do inData[i] := newData[i];
end;

procedure expand(inData: array of Byte; var outData: array of Byte);
var
  i: Integer;
begin
  FillChar(outData, 6, 0);
  for i := 0 to 47 do
    if (inData[BitExp[i] shr 3] and (1 shl (7-(BitExp[i] and $07)))) <> 0 then
      outData[i shr 3] := outData[i shr 3] or (1 shl (7-(i and $07)));
end;

procedure permutation(var inData: array of Byte);
var
  newData: array[0..3] of Byte;
  i: Integer;
begin
  FillChar(newData, 4, 0);
  for i := 0 to 31 do
    if (inData[BitPM[i] shr 3] and (1 shl (7-(BitPM[i] and $07)))) <> 0 then
      newData[i shr 3] := newData[i shr 3] or (1 shl (7-(i and $07)));
  for i := 0 to 3 do inData[i] := newData[i];
end;

function si(s,inByte: Byte): Byte;
var
  c: Byte;
begin
  c := (inByte and $20) or ((inByte and $1e) shr 1) or
    ((inByte and $01) shl 4);
  Result := (sBox[s][c] and $0f);
end;

procedure permutationChoose1(inData: array of Byte;
  var outData: array of Byte);
var
  i: Integer;
begin
  FillChar(outData, 7, 0);
  for i := 0 to 55 do
    if (inData[BitPMC1[i] shr 3] and (1 shl (7-(BitPMC1[i] and $07)))) <> 0 then
      outData[i shr 3] := outData[i shr 3] or (1 shl (7-(i and $07)));
end;

procedure permutationChoose2(inData: array of Byte;
  var outData: array of Byte);
var
  i: Integer;
begin
  FillChar(outData, 6, 0);
  for i := 0 to 47 do
    if (inData[BitPMC2[i] shr 3] and (1 shl (7-(BitPMC2[i] and $07)))) <> 0 then
      outData[i shr 3] := outData[i shr 3] or (1 shl (7-(i and $07)));
end;

procedure cycleMove(var inData: array of Byte; bitMove: Byte);
var
  i: Integer;
begin
  for i := 0 to bitMove - 1 do
  begin
    inData[0] := (inData[0] shl 1) or (inData[1] shr 7);
    inData[1] := (inData[1] shl 1) or (inData[2] shr 7);
    inData[2] := (inData[2] shl 1) or (inData[3] shr 7);
    inData[3] := (inData[3] shl 1) or ((inData[0] and $10) shr 4);
    inData[0] := (inData[0] and $0f);
  end;
end;

procedure makeKey(inKey: array of Byte; var outKey: array of TKeyByte);
const
  bitDisplace: array[0..15] of Byte =
    ( 1,1,2,2, 2,2,2,2, 1,2,2,2, 2,2,2,1 );
var
  outData56: array[0..6] of Byte;
  key28l: array[0..3] of Byte;
  key28r: array[0..3] of Byte;
  key56o: array[0..6] of Byte;
  i: Integer;
begin
  permutationChoose1(inKey, outData56);

  key28l[0] := outData56[0] shr 4;
  key28l[1] := (outData56[0] shl 4) or (outData56[1] shr 4);
  key28l[2] := (outData56[1] shl 4) or (outData56[2] shr 4);
  key28l[3] := (outData56[2] shl 4) or (outData56[3] shr 4);
  key28r[0] := outData56[3] and $0f;
  key28r[1] := outData56[4];
  key28r[2] := outData56[5];
  key28r[3] := outData56[6];

  for i := 0 to 15 do
  begin