QQ加密算法浅谈(TEA加解密算法)

Tencent QQ的加密算法就采用了 TEA算法

 

TEA(Tiny Encryption Algorithm) 是一种优秀的数据加密算法，虽然它比 DES(Data Encryption Standard) 要简单得多， 但有很强的抗差分分析能力，加密速度也比 DES 快得多，而且对 64 位数据加密的密钥长达 128 位，安全性相当好。

 

Pascal(Delphi)代码如下: ntohl函数来自 winsock单元

type
  TLongintArray = array[0..3] of Longword;
  PLongintArray = ^TLongintArray;

 

procedure Encipher(v, k, w: PLongintArray);
var
  y, z, a, b, c, d, sum, delta: Longword;
  n: Longint;
begin
  y := ntohl(v^[0]);  z := ntohl(v^[1]); a := ntohl(k^[0]);  b := ntohl(k^[1]);

  c := ntohl(k^[2]);  d := ntohl(k^[3]);  sum := 0;  delta := $9E3779B9;
  for n := 1 to 16 do
  begin
    Inc(sum, delta);
    Inc(y, ((z shl 4) + a) xor (z + sum) xor ((z shr 5) + b));
    Inc(z, ((y shl 4) + c) xor (y + sum) xor ((y shr 5) + d));
  end;
  w^[0] := htonl(y);
  w^[1] := htonl(z);
end;

procedure Decipher(v, k, w: PLongintArray);
var
  y, z, a, b, c, d, sum, delta: Longword;
  n: Longint;
begin
  y := ntohl(v^[0]);  z := ntohl(v^[1]);  a := ntohl(k^[0]);  b := ntohl(k^[1]);
  c := ntohl(k^[2]);  d := ntohl(k^[3]);  sum := $E3779B90;  delta := $9E3779B9;
  for n := 1 to 16 do
  begin
    Dec(z, ((y shl 4) + c) xor (y + sum) xor ((y shr 5) + d));
    Dec(y, ((z shl 4) + a) xor (z + sum) xor ((z shr 5) + b));
    Dec(sum, delta);
  end;
  w^[0] := htonl(y);
  w^[1] := htonl(z);
end;

 

C/C++代码如下: 转的地方没注作者

void encipher( unsigned long * const v, const unsigned long * const k )
{
    register unsigned long y = v[0], z = v[1], sum = 0, delta = 0x9E3779B9,
        a = k[0], b = k[1], c = k[2], d = k[3], n = 32;

    while ( n-- > 0 )
    {
        sum += delta;
        y += ( z << 4 ) + a ^ z + sum ^ ( z >> 5 ) + b;
        z += ( y << 4 ) + c ^ y + sum ^ ( y >> 5 ) + d;
    }
    v[0] = y;
    v[1] = z;
}

void decipher( unsigned long * const v, const unsigned long * const k )
{
    register unsigned long y = v[0], z = v[1], sum = 0xC6EF3720, delta = 0x9E3779B9,
        a = k[0], b = k[1], c = k[2], d = k[3], n = 32;

    // sum = delta << 5, in general sum = delta * n
    while ( n-- > 0 )
    {
        z -= ( y << 4 ) + c ^ y + sum ^ ( y >> 5 ) + d;
        y -= ( z << 4 ) + a ^ z + sum ^ ( z >> 5 ) + b;
        sum -= delta;
    }
    v[0] = y;
    v[1] = z;
}

 

头次用MSN 空间见笑 ,其实模拟QQ的程序我很早以前就写好了,没事弄弄MSN Spaces也没什么好发的就发发这个吧!Didi MSN:[email protected] EMAIL:[email protected]!

 

首发于MSN Spaces http://spaces.msn.com/banzcn/ 欢迎大家来看~ 呵~

 

下载单元 http://didi.99ss.com/AboutTencentQQ/UniTEA.pas 其它的等我慢满从MSN转过来吧!

Didi无聊第二篇(MSN空间,CSDN Blog)