请教熟悉 XXTEA 加密解密的朋友

KaKaKaKa 2012-05-21 03:49:07



#include "stdio.h"

#include "windows.h"



#define MX (z>>5^y<<2) + (y>>3^z<<4)^(sum^y) + (k[p&3^e]^z);

 

  long btea(long* v, long n, long* k) {

    unsigned long z=v[n-1], y=v[0], sum=0, e, DELTA=0x9e3779b9;

    long p, q ;

    if (n > 1) {          /* Coding Part */

      q = 6 + 52/n;

      while (q-- > 0) {

        sum += DELTA;

        e = (sum >> 2) & 3;

        for (p=0; p<n-1; p++) y = v[p+1], z = v[p] += MX;

        y = v[0];

        z = v[n-1] += MX;

      }

      return 0 ; 

    } else if (n < -1) {  /* Decoding Part */

      n = -n;

      q = 6 + 52/n;

      sum = q*DELTA ;

      while (sum != 0) {

        e = (sum >> 2) & 3;

        for (p=n-1; p>0; p--) z = v[p-1], y = v[p] -= MX;

        z = v[n-1];

        y = v[0] -= MX;

        sum -= DELTA;

      }

      return 0;

    }

    return 1;

  }









//以下测试XXTEA加密和解密功能

int main()

{

	long ret = 0;



	TCHAR a[11] = TEXT("XXTEA测试字符串");

	long k[4] = {111,222,333,444};



	//加密

         ret = btea((long *)a,10,k);

	printf("En:%ld	%s\n",ret,a);



         //解密

	ret = btea((long *)a,-10,k);

	printf("De:%ld	%s\n",ret,a);



	

	getchar();

	return 0;

}