DESTR.pas | searchcode

/test/HGEMir3/Client??3DX/DESTR.pas

http://my-chuanqi.googlecode.com/
Pascal | 400 lines | 350 code | 47 blank | 3 comment | 64 complexity | 041d91aa8f65a2a805d134781e6df4d3 MD5 | raw file

unit DESTR;



interface

uses

  SysUtils, Classes, Windows;

type

  TKeyByte = array[0..999] 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 = //????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 = //????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 = // ?????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 = //????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?

  ((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 = //????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 = //????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

  subKey: array[0..15] of TKeyByte;



implementation



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

    cycleMove(key28l, bitDisplace[I]);

    cycleMove(key28r, bitDisplace[I]);

    key56o[0] := (key28l[0] shl 4) or (key28l[1] shr 4);

    key56o[1] := (key28l[1] shl 4) or (key28l[2] shr 4);

    key56o[2] := (key28l[2] shl 4) or (key28l[3] shr 4);

    key56o[3] := (key28l[3] shl 4) or (key28r[0]);

    key56o[4] := key28r[1];

    key56o[5] := key28r[2];

    key56o[6] := key28r[3];

    permutationChoose2(key56o, outKey[I]);

  end;

end;



procedure Encry(inData, subKey: array of Byte;

  var outData: array of Byte);

var

  outBuf: array[0..5] of Byte;

  Buf: array[0..7] of Byte;

  I: Integer;

begin

  Expand(inData, outBuf);

  for I := 0 to 5 do outBuf[I] := outBuf[I] xor subKey[I];

  Buf[0] := outBuf[0] shr 2;

  Buf[1] := ((outBuf[0] and $03) shl 4) or (outBuf[1] shr 4);

  Buf[2] := ((outBuf[1] and $0F) shl 2) or (outBuf[2] shr 6);

  Buf[3] := outBuf[2] and $3F;

  Buf[4] := outBuf[3] shr 2;

  Buf[5] := ((outBuf[3] and $03) shl 4) or (outBuf[4] shr 4);

  Buf[6] := ((outBuf[4] and $0F) shl 2) or (outBuf[5] shr 6);

  Buf[7] := outBuf[5] and $3F;

  for I := 0 to 7 do Buf[I] := si(I, Buf[I]);

  for I := 0 to 3 do outBuf[I] := (Buf[I * 2] shl 4) or Buf[I * 2 + 1];

  permutation(outBuf);

  for I := 0 to 3 do outData[I] := outBuf[I];

end;



procedure desData(desMode: TDesMode;

  inData: array of Byte; var outData: array of Byte);

// inData, outData ??8Bytes?????

var

  I, J: Integer;

  temp, Buf: array[0..3] of Byte;

begin

  for I := 0 to 7 do outData[I] := inData[I];

  initPermutation(outData);

  if desMode = dmEncry then begin

    for I := 0 to 15 do begin

      for J := 0 to 3 do temp[J] := outData[J]; //temp = Ln

      for J := 0 to 3 do outData[J] := outData[J + 4]; //Ln+1 = Rn

      Encry(outData, subKey[I], Buf); //Rn ==Kn==> buf

      for J := 0 to 3 do outData[J + 4] := temp[J] xor Buf[J]; //Rn+1 = Ln^buf

    end;



    for J := 0 to 3 do temp[J] := outData[J + 4];

    for J := 0 to 3 do outData[J + 4] := outData[J];

    for J := 0 to 3 do outData[J] := temp[J];

  end

  else if desMode = dmDecry then begin

    for I := 15 downto 0 do begin

      for J := 0 to 3 do temp[J] := outData[J];

      for J := 0 to 3 do outData[J] := outData[J + 4];

      Encry(outData, subKey[I], Buf);

      for J := 0 to 3 do outData[J + 4] := temp[J] xor Buf[J];

    end;

    for J := 0 to 3 do temp[J] := outData[J + 4];

    for J := 0 to 3 do outData[J + 4] := outData[J];

    for J := 0 to 3 do outData[J] := temp[J];

  end;

  conversePermutation(outData);

end;



//////////////////////////////////////////////////////////////



function EncryStr(Str, Key: string): string;

var

  StrByte, OutByte, KeyByte: array[0..7] of Byte;

  StrResult: string;

  I, J: Integer;

begin

  if (Length(Str) > 0) and (Ord(Str[Length(Str)]) = 0) then

    raise Exception.Create('Error: the last char is NULL char.');

  if Length(Key) < 8 then

    while Length(Key) < 8 do Key := Key + Chr(0);

  while Length(Str) mod 8 <> 0 do Str := Str + Chr(0);



  for J := 0 to 7 do KeyByte[J] := Ord(Key[J + 1]);

  makeKey(KeyByte, subKey);



  StrResult := '';



  for I := 0 to Length(Str) div 8 - 1 do begin

    for J := 0 to 7 do

      StrByte[J] := Ord(Str[I * 8 + J + 1]);

    desData(dmEncry, StrByte, OutByte);

    for J := 0 to 7 do

      StrResult := StrResult + Chr(OutByte[J]);

  end;



  Result := StrResult;

end;



function DecryStr(Str, Key: string): string;

var

  StrByte, OutByte, KeyByte: array[0..7] of Byte;

  StrResult: string;

  I, J: Integer;

begin

  if Length(Key) < 8 then

    while Length(Key) < 8 do Key := Key + Chr(0);



  for J := 0 to 7 do KeyByte[J] := Ord(Key[J + 1]);

  makeKey(KeyByte, subKey);



  StrResult := '';



  for I := 0 to Length(Str) div 8 - 1 do begin

    for J := 0 to 7 do StrByte[J] := Ord(Str[I * 8 + J + 1]);

    desData(dmDecry, StrByte, OutByte);

    for J := 0 to 7 do

      StrResult := StrResult + Chr(OutByte[J]);

  end;

  while (Length(StrResult) > 0) and

    (Ord(StrResult[Length(StrResult)]) = 0) do

    Delete(StrResult, Length(StrResult), 1);

  Result := StrResult;

end;



///////////////////////////////////////////////////////////



function EncryStrHex(Str, Key: string): string;

var

  StrResult, TempResult, temp: string;

  I: Integer;

begin

  TempResult := EncryStr(Str, Key);

  StrResult := '';

  for I := 0 to Length(TempResult) - 1 do begin

    temp := Format('%x', [Ord(TempResult[I + 1])]);

    if Length(temp) = 1 then temp := '0' + temp;

    StrResult := StrResult + temp;

  end;

  Result := StrResult;

end;



function DecryStrHex(StrHex, Key: string): string;

  function HexToInt(Hex: string): Integer;

  var

    I, Res: Integer;

    Ch: Char;

  begin

    Res := 0;

    for I := 0 to Length(Hex) - 1 do begin

      Ch := Hex[I + 1];

      if (Ch >= '0') and (Ch <= '9') then

        Res := Res * 16 + Ord(Ch) - Ord('0')

      else if (Ch >= 'A') and (Ch <= 'F') then

        Res := Res * 16 + Ord(Ch) - Ord('A') + 10

      else if (Ch >= 'a') and (Ch <= 'f') then

        Res := Res * 16 + Ord(Ch) - Ord('a') + 10

      else raise Exception.Create('Error: not a Hex String');

    end;

    Result := Res;

  end;



var

  Str, temp: string;

  I: Integer;

begin

  Str := '';

  for I := 0 to Length(StrHex) div 2 - 1 do begin

    temp := Copy(StrHex, I * 2 + 1, 2);

    Str := Str + Chr(HexToInt(temp));

  end;

  Result := DecryStr(Str, Key);

end;



end.