md5算法模块(delphi).txt

md5加密算法

标 题:MD5程序（Delphi）放送......见笑了 (3千字)
发信人:upfeed1
时 间:2002-8-19 17:46:16
详细信息:


/*** Source Code of MD5 ***/ 
/  written BY upfeed[FCG]  / 
/**************************/ 

下面的函数是计算核心，至于分组和填充部分就略去了。 
==================================================== 
参数说明： 
AA,BB,CC,DD是摘要信息，一般初始化为 
AA := $67452301; 
BB := $EFCDAB89; 
CC := $98BADCFE; 
DD := $10325476; 
MSGs是一个长64的LongWord数组，保存的就是要摘要的信息 
==================================================== 
procedure TMainForm.MD5(var AA, BB, CC, DD: LongWord; MSGs: array of LongWord); 
var 
  A, B, C, D: LongWord; 
  T: array[1..64] of LongWord; 
  i: integer; 

//没有循环左移的位运算，自己写一个 
  function ROL(r: LongWord; bit: byte): LongWord; 
  var 
    ii: byte; 
  begin 
    for ii:=1 to bit do 
      if r and $80000000 = $80000000 then 
        r := (r shl 1) or $01 
      else 
        r := (r shl 1); 
    Result := r; 
  end; 

//四轮运算中的函数定义，也可以自行定义的 
  procedure FF(var a: LongWord; b, c, d: LongWord; k, s, i: byte); 
  begin 
    a := b + ROL((a + ((b and c) or (not b and d)) + MSGs[k] + T[i]), s); 
  end; 
  procedure GG(var a: LongWord; b, c, d: LongWord; k, s, i: byte); 
  begin 
    a := b + ROL((a + ((b and d) or (c and not d)) + MSGs[k] + T[i]), s); 
  end; 
  procedure HH(var a: LongWord; b, c, d: LongWord; k, s, i: byte); 
  begin 
    a := b + ROL((a + (b xor c xor d) + MSGs[k] + T[i]), s); 
  end; 
  procedure II(var a: LongWord; b, c, d: LongWord; k, s, i: byte); 
  begin 
    a := b + ROL((a + (c xor (b or not d)) + MSGs[k] + T[i]), s); 
  end; 
  
begin 
  fillchar(T, sizeof(T), 0); 

//常数数组的初始化，通常是这种形式，当然可以自己做手脚的 
  for i:=1 to 64 do 
    T[i] := Trunc(4294967296*abs(sin(i))); 

  A := AA; B := BB; C := CC; D := DD; 
//第一轮 
  FF(A, B, C, D, 0, 7, 1); FF(D, A, B, C, 1, 12, 2); FF(C, D, A, B, 2, 17, 3); FF(B, C, D, A, 3, 22, 4); 
  FF(A, B, C, D, 4, 7, 5); FF(D, A, B, C, 5, 12, 6); FF(C, D, A, B, 6, 17, 7); FF(B, C, D, A, 7, 22, 8); 
  FF(A, B, C, D, 8, 7, 9); FF(D, A, B, C, 9, 12,10); FF(C, D, A, B, 10,17,11); FF(B, C, D, A, 11,22,12); 
  FF(A, B, C, D, 12,7,13); FF(D, A, B, C, 13,12,14); FF(C, D, A, B, 14,17,15); FF(B, C, D, A, 15,22,16); 

//第二轮 
  GG(A, B, C, D, 1, 5,17); GG(D, A, B, C, 6,  9,18); GG(C, D, A, B, 11,14,19); GG(B, C, D, A, 0, 20,20); 
  GG(A, B, C, D, 5, 5,21); GG(D, A, B, C, 10, 9,22); GG(C, D, A, B, 15,14,23); GG(B, C, D, A, 4, 20,24); 
  GG(A, B, C, D, 9, 5,25); GG(D, A, B, C, 14, 9,26); GG(C, D, A, B, 3, 14,27); GG(B, C, D, A, 8, 20,28); 
  GG(A, B, C, D, 13,5,29); GG(D, A, B, C, 2,  9,30); GG(C, D, A, B, 7, 14,31); GG(B, C, D, A, 12,20,32); 

//第三轮 
  HH(A, B, C, D, 5, 4,33); HH(D, A, B, C, 8, 11,34); HH(C, D, A, B, 11,16,35); HH(B, C, D, A, 14,23,36); 
  HH(A, B, C, D, 1, 4,37); HH(D, A, B, C, 4, 11,38); HH(C, D, A, B, 7, 16,39); HH(B, C, D, A, 10,23,40); 
  HH(A, B, C, D, 13,4,41); HH(D, A, B, C, 0, 11,42); HH(C, D, A, B, 3, 16,43); HH(B, C, D, A, 6, 23,44); 
  HH(A, B, C, D, 9, 4,45); HH(D, A, B, C, 12,11,46); HH(C, D, A, B, 15,16,47); HH(B, C, D, A, 2, 23,48); 

//第四轮 
  II(A, B, C, D, 0, 6,49); II(D, A, B, C, 7, 10,50); II(C, D, A, B, 14,15,51); II(B, C, D, A, 5, 21,52); 
  II(A, B, C, D, 12,6,53); II(D, A, B, C, 3, 10,54); II(C, D, A, B, 10,15,55); II(B, C, D, A, 1, 21,56); 
  II(A, B, C, D, 8, 6,57); II(D, A, B, C, 15,10,58); II(C, D, A, B, 6, 15,59); II(B, C, D, A, 13,21,60); 
  II(A, B, C, D, 4, 6,61); II(D, A, B, C, 11,10,62); II(C, D, A, B, 2, 15,63); II(B, C, D, A, 9, 21,64); 

  AA := A + AA; 
  BB := B + BB; 
  CC := C + CC; 
  DD := D + DD; 
end; 

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