md.pas

木马源程序,供大家研究

  GG (b, c, d, a, x[13], S24); //* 24 */
  GG (a, b, c, d, x[ 2], S21); //* 25 */
  GG (d, a, b, c, x[ 6], S22); //* 26 */
  GG (c, d, a, b, x[10], S23); //* 27 */
  GG (b, c, d, a, x[14], S24); //* 28 */
  GG (a, b, c, d, x[ 3], S21); //* 29 */
  GG (d, a, b, c, x[ 7], S22); //* 30 */
  GG (c, d, a, b, x[11], S23); //* 31 */
  GG (b, c, d, a, x[15], S24); //* 32 */

  //* Round 3 */
  HH (a, b, c, d, x[ 0], S31); //* 33 */
  HH (d, a, b, c, x[ 8], S32); //* 34 */
  HH (c, d, a, b, x[ 4], S33); //* 35 */
  HH (b, c, d, a, x[12], S34); //* 36 */
  HH (a, b, c, d, x[ 2], S31); //* 37 */
  HH (d, a, b, c, x[10], S32); //* 38 */
  HH (c, d, a, b, x[ 6], S33); //* 39 */
  HH (b, c, d, a, x[14], S34); //* 40 */
  HH (a, b, c, d, x[ 1], S31); //* 41 */
  HH (d, a, b, c, x[ 9], S32); //* 42 */
  HH (c, d, a, b, x[ 5], S33); //* 43 */
  HH (b, c, d, a, x[13], S34); //* 44 */
  HH (a, b, c, d, x[ 3], S31); //* 45 */
  HH (d, a, b, c, x[11], S32); //* 46 */
  HH (c, d, a, b, x[ 7], S33); //* 47 */
  HH (b, c, d, a, x[15], S34); //* 48 */

  //State updates
  state[0] := state[0] + a;
  state[1] := state[1] + b;
  state[2] := state[2] + c;
  state[3] := state[3] + d;
end;

procedure MDUpdate(context: PMD4Ctx; input: Pointer; inputLen: LongWord; tr_func: TMDTransform);
var
  i, index, partLen: LongWord;
begin
  //* Compute number of bytes mod 64 */
  index := (context^.count[0] shr 3) and $3F;

  //* Update number of bits */
  context^.count[0] := context^.count[0] + inputLen shl 3;
  if (context^.count[0] < (inputLen shl 3)) then
    Inc(context^.count[1]);

  context^.count[1] := context^.count[1] + inputLen shr 29;
  partLen := 64 - index;
  //* Transform as many times as possible.*/
  if (inputLen >= partLen) then
  begin
    Move(input^, context^.buffer[index], partLen);
    {output, input, len}
    tr_func(context^.state, @context^.buffer);
    i := partLen;
    while i + 63 < inputLen do
    begin
      MD4Transform(context^.state, Addr(PByteArray(input)^[i]));
      Inc(i, 64);
    end;
    index := 0;
  end
  else
    i := 0;
  //* Buffer remaining input */
  Move(PByteArray(input)^[i], context^.buffer[index], inputLen - i);
end;

function MDFinal(context: PMD4Ctx; tr_func: TMDTransform): String;
var
  digest: array[0..15] of Char;
  bits: array[0..7] of Char;
  index, padLen: LongWord;
begin
  //* Save number of bits */
  MDEncode(@bits, @context^.count, 8);

  //* Pad out to 56 mod 64. //*/
  index := (context^.count[0] shr 3) and $3f;
  if (index < 56) then
    padLen := 56 - index
  else
    padLen := 120 - index;

  MDUpdate(context, @MD_PADDING, padLen, tr_func);

  //* Append length (before padding) */
  MDUpdate(context, @bits, 8, tr_func);
  //* Store state in digest */
  MDEncode(@digest, @context^.state, 16);

  //* Zeroize sensitive information.*/
  FillChar(context^, 0, SizeOf(TMD4Ctx));

  Result := '';
  for index := 0 to 15 do
    Result := Result + IntToHex(Ord(digest[index]), 2);
end;

{-- MD5 --------------------------------------------------------}
const
  MD5_S11 = 7;
  MD5_S12 = 12;
  MD5_S13 = 17;
  MD5_S14 = 22;
  MD5_S21 = 5;
  MD5_S22 = 9;
  MD5_S23 = 14;
  MD5_S24 = 20;
  MD5_S31 = 4;
  MD5_S32 = 11;
  MD5_S33 = 16;
  MD5_S34 = 23;
  MD5_S41 = 6;
  MD5_S42 = 10;
  MD5_S43 = 15;
  MD5_S44 = 21;

function MD5_G(x, y, z: LongWord): LongWord; assembler;
{begin
  Result := (x and y) or (x and z) or (y and not z);
end;}
asm
  push  ecx
  and   ecx,eax
  and   eax,edx
  or    eax,ecx
  pop   ecx
  not   ecx
  and   edx,ecx
  or    eax,edx
end;

function I(x, y, z: LongWord): LongWord; assembler;
{begin
  Result := y xor (x or (not z));
end;}
asm
  not   ecx
  or    eax,ecx
  xor   eax,edx
end;

procedure MD5_FF(var a: LongWord; b, c, d, x, s, ac: LongWord);
begin
  a := a + F(b, c, d) + x + ac;
  a := rol(a, s);
  a := a + b;
end;

procedure MD5_GG(var a: LongWord; b, c, d, x, s, ac: LongWord);
begin
  a := a + MD5_G(b, c, d) + x + ac;
  a := rol(a, s);
  a := a + b;
end;

procedure MD5_HH(var a: LongWord; b, c, d, x, s, ac: LongWord);
begin
 a := a + H(b, c, d) + x + ac;
 a := rol(a, s);
 a := a + b;
end;

procedure MD5_II(var a: LongWord; b, c, d, x, s, ac: LongWord);
begin
 a := a + I(b, c, d) + x + ac;
 a := rol(a, s);
 a := a + b;
end;

procedure MD5Transform (var state: array of LongWord; block: Pointer);
var
  a, b, c, d: LongWord;
  x: array[0..15] of LongWord;
begin
  a := state[0]; b := state[1]; c := state[2]; d := state[3];
  MDDecode(@x, block, 64);

  //* Round 1 */
  MD5_FF(a, b, c, d, x[ 0], MD5_S11, $d76aa478); //* 1 */
  MD5_FF(d, a, b, c, x[ 1], MD5_S12, $e8c7b756); //* 2 */
  MD5_FF(c, d, a, b, x[ 2], MD5_S13, $242070db); //* 3 */
  MD5_FF(b, c, d, a, x[ 3], MD5_S14, $c1bdceee); //* 4 */
  MD5_FF(a, b, c, d, x[ 4], MD5_S11, $f57c0faf); //* 5 */
  MD5_FF(d, a, b, c, x[ 5], MD5_S12, $4787c62a); //* 6 */
  MD5_FF(c, d, a, b, x[ 6], MD5_S13, $a8304613); //* 7 */
  MD5_FF(b, c, d, a, x[ 7], MD5_S14, $fd469501); //* 8 */
  MD5_FF(a, b, c, d, x[ 8], MD5_S11, $698098d8); //* 9 */
  MD5_FF(d, a, b, c, x[ 9], MD5_S12, $8b44f7af); //* 10 */
  MD5_FF(c, d, a, b, x[10], MD5_S13, $ffff5bb1); //* 11 */
  MD5_FF(b, c, d, a, x[11], MD5_S14, $895cd7be); //* 12 */
  MD5_FF(a, b, c, d, x[12], MD5_S11, $6b901122); //* 13 */
  MD5_FF(d, a, b, c, x[13], MD5_S12, $fd987193); //* 14 */
  MD5_FF(c, d, a, b, x[14], MD5_S13, $a679438e); //* 15 */
  MD5_FF(b, c, d, a, x[15], MD5_S14, $49b40821); //* 16 */

  //* Round 2 */
  MD5_GG(a, b, c, d, x[ 1], MD5_S21, $f61e2562); //* 17 */
  MD5_GG(d, a, b, c, x[ 6], MD5_S22, $c040b340); //* 18 */
  MD5_GG(c, d, a, b, x[11], MD5_S23, $265e5a51); //* 19 */
  MD5_GG(b, c, d, a, x[ 0], MD5_S24, $e9b6c7aa); //* 20 */
  MD5_GG(a, b, c, d, x[ 5], MD5_S21, $d62f105d); //* 21 */
  MD5_GG(d, a, b, c, x[10], MD5_S22, $02441453); //* 22 */
  MD5_GG(c, d, a, b, x[15], MD5_S23, $d8a1e681); //* 23 */
  MD5_GG(b, c, d, a, x[ 4], MD5_S24, $e7d3fbc8); //* 24 */
  MD5_GG(a, b, c, d, x[ 9], MD5_S21, $21e1cde6); //* 25 */
  MD5_GG(d, a, b, c, x[14], MD5_S22, $c33707d6); //* 26 */
  MD5_GG(c, d, a, b, x[ 3], MD5_S23, $f4d50d87); //* 27 */
  MD5_GG(b, c, d, a, x[ 8], MD5_S24, $455a14ed); //* 28 */
  MD5_GG(a, b, c, d, x[13], MD5_S21, $a9e3e905); //* 29 */
  MD5_GG(d, a, b, c, x[ 2], MD5_S22, $fcefa3f8); //* 30 */
  MD5_GG(c, d, a, b, x[ 7], MD5_S23, $676f02d9); //* 31 */
  MD5_GG(b, c, d, a, x[12], MD5_S24, $8d2a4c8a); //* 32 */

  //* Round 3 */
  MD5_HH(a, b, c, d, x[ 5], MD5_S31, $fffa3942); //* 33 */
  MD5_HH(d, a, b, c, x[ 8], MD5_S32, $8771f681); //* 34 */
  MD5_HH(c, d, a, b, x[11], MD5_S33, $6d9d6122); //* 35 */
  MD5_HH(b, c, d, a, x[14], MD5_S34, $fde5380c); //* 36 */
  MD5_HH(a, b, c, d, x[ 1], MD5_S31, $a4beea44); //* 37 */
  MD5_HH(d, a, b, c, x[ 4], MD5_S32, $4bdecfa9); //* 38 */
  MD5_HH(c, d, a, b, x[ 7], MD5_S33, $f6bb4b60); //* 39 */
  MD5_HH(b, c, d, a, x[10], MD5_S34, $bebfbc70); //* 40 */
  MD5_HH(a, b, c, d, x[13], MD5_S31, $289b7ec6); //* 41 */
  MD5_HH(d, a, b, c, x[ 0], MD5_S32, $eaa127fa); //* 42 */
  MD5_HH(c, d, a, b, x[ 3], MD5_S33, $d4ef3085); //* 43 */
  MD5_HH(b, c, d, a, x[ 6], MD5_S34, $04881d05); //* 44 */
  MD5_HH(a, b, c, d, x[ 9], MD5_S31, $d9d4d039); //* 45 */
  MD5_HH(d, a, b, c, x[12], MD5_S32, $e6db99e5); //* 46 */
  MD5_HH(c, d, a, b, x[15], MD5_S33, $1fa27cf8); //* 47 */
  MD5_HH(b, c, d, a, x[ 2], MD5_S34, $c4ac5665); //* 48 */

  //* Round 4 */
  MD5_II(a, b, c, d, x[ 0], MD5_S41, $f4292244); //* 49 */
  MD5_II(d, a, b, c, x[ 7], MD5_S42, $432aff97); //* 50 */
  MD5_II(c, d, a, b, x[14], MD5_S43, $ab9423a7); //* 51 */
  MD5_II(b, c, d, a, x[ 5], MD5_S44, $fc93a039); //* 52 */
  MD5_II(a, b, c, d, x[12], MD5_S41, $655b59c3); //* 53 */
  MD5_II(d, a, b, c, x[ 3], MD5_S42, $8f0ccc92); //* 54 */
  MD5_II(c, d, a, b, x[10], MD5_S43, $ffeff47d); //* 55 */
  MD5_II(b, c, d, a, x[ 1], MD5_S44, $85845dd1); //* 56 */
  MD5_II(a, b, c, d, x[ 8], MD5_S41, $6fa87e4f); //* 57 */
  MD5_II(d, a, b, c, x[15], MD5_S42, $fe2ce6e0); //* 58 */
  MD5_II(c, d, a, b, x[ 6], MD5_S43, $a3014314); //* 59 */
  MD5_II(b, c, d, a, x[13], MD5_S44, $4e0811a1); //* 60 */
  MD5_II(a, b, c, d, x[ 4], MD5_S41, $f7537e82); //* 61 */
  MD5_II(d, a, b, c, x[11], MD5_S42, $bd3af235); //* 62 */
  MD5_II(c, d, a, b, x[ 2], MD5_S43, $2ad7d2bb); //* 63 */
  MD5_II(b, c, d, a, x[ 9], MD5_S44, $eb86d391); //* 64 */

  state[0] := state[0] + a;
  state[1] := state[1] + b;
  state[2] := state[2] + c;
  state[3] := state[3] + d;
end;

end.