jgg encrypt

Jgg.cpp

#include "Jgg.h"

#define REAL_SHIFT(i)  (i%8+1)
#define KEY_BYTE	0xE9

JGG_KEY jggSetup(unsigned char *key, int len)
{
	JGG_KEY jk;
	int i=0, j=0, k=0;

    for( i = 0; i < 256; i++ )
    {
        jk.m[i] = i;
    }
	
    for( i = 0; i < 256; i++ )
    {
        j = (unsigned char) ( j + jk.m[i] + key[k] + j%7 + i%11);
		if( i != j)
		{
			char tmp = jk.m[i];
			jk.m[i] = jk.m[j];
			jk.m[j] = tmp;
		}
        if( ++k >= len ) k = 0;
    }
	return jk;
}

void encrypt(JGG_KEY &jk, const unsigned char *in, unsigned char *out, int len)
{
	int i=0;
	int x=0;
	int y=0;
	for (i=0; i<len; i++)
	{
		unsigned char a = in[i] ^ KEY_BYTE ^ (unsigned char)i;
		unsigned char b = REAL_SHIFT(i);
		__asm
		{
s1:
			rol a, 1
			dec b
			cmp b,0
			jg	s1
		}
		x = (unsigned char)(x + 1);
		y = (unsigned char)(y + jk.m[x]);
		if (x != y)
		{
			char tmp = jk.m[x];
			jk.m[x] = jk.m[y];
			jk.m[y] = tmp;
		}
		out[i] = a^(unsigned char)jk.m[(unsigned char)(jk.m[x]+jk.m[y])];
	}
}

void decrypt(JGG_KEY &jk, const unsigned char *in, unsigned char *out, int len)
{
	int i=0;
	int x=0;
	int y=0;
	for (i=0; i<len; i++)
	{
		unsigned char a = 0;
		unsigned char b = 0;
		x = (unsigned char)(x + 1);
		y = (unsigned char)(y + jk.m[x]);
		if (x != y)
		{
			char tmp = jk.m[x];
			jk.m[x] = jk.m[y];
			jk.m[y] = tmp;
		}

		a = in[i]^(unsigned char)jk.m[(unsigned char)(jk.m[x]+jk.m[y])];
		b = REAL_SHIFT(i);
		__asm
		{
s1:
			ror a, 1
			dec b
			cmp b,0
			jg  s1
		}
		out[i] = a ^ KEY_BYTE ^ (unsigned char)i;
	}
}

void jggEncrypt(JGG_KEY &jk, const unsigned char *in, unsigned char *out, int len, bool enc)
{
	enc? encrypt(jk, in, out, len):decrypt(jk, in, out, len);
}

Jgg.h

#ifndef _JGG_H
#define _JGG_H

struct JGG_KEY
{
  char m[256];
};

JGG_KEY jggSetup(unsigned char *key, int len);
void jggEncrypt(JGG_KEY &jk, const unsigned char *in, unsigned char *out, int len, bool enc);

#endif //_JGG_H
/*!
example:

#include "jgg.h"
#include <string>

int main()
{
  unsigned char buf[256] = {0};
	unsigned char buf2[256] = {0};

	std::string src = "哈哈 ni mei 啊。。--￥%&*！！！";
	printf("src:%s\n", src.c_str());
	std::string key = "i am a key...";
	jggEncrypt(jggSetup((unsigned char*)key.c_str(), key.length()), (unsigned char*)src.c_str(), buf, src.length(), true);
	jggEncrypt(jggSetup((unsigned char*)key.c_str(), key.length()), buf, buf2, src.length(), false);
	printf("dst:%s\n", buf2);
	return 0;
}

*/