jgg2 encrypt

Jgg2.cpp

/*!
  jgg encrypt
*/
#include <string>
#include <assert.h>

#define JGG_CONST_STRING	" !\"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\\]^_`abcdefghijklmnopqrstuvwxyz{|}~"
//#define CONST_STRING	" !\"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\\]^_`abcdefghijklmnopqrstuvwxyz{|}~\r\n\t"

#define JGG_SIZE		(sizeof(JGG_CONST_STRING)-1)

struct JGG_KEY
{
	int x;
	int y;
	char m[JGG_SIZE+1];
};

JGG_KEY jggSetup(const unsigned char * key, int len);
JGG_KEY jggSetup(const std::string& key);

bool jggEncrypt(JGG_KEY &jk, unsigned char * data, int ilen, bool enc);
std::string jggEncrypt(JGG_KEY &jk, const std::string &src, bool enc);

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

	for( i=0; i<JGG_SIZE; i++ )
	{
		j = (unsigned char)(j + jk.m[i] + key[k])%JGG_SIZE;

		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;
}

JGG_KEY jggSetup(const std::string& key)
{
	return jggSetup((const unsigned char *)key.c_str(), (int)key.length());
}

bool jggEncrypt(JGG_KEY &rk, unsigned char * data, int ilen, bool enc)
{
	int i, j, x, y, k;
	bool bFind = false;

	x = rk.x;
	y = rk.y;

	for( i = 0; i < ilen; i++ )
	{
		//check
		bFind = false;
		for (j=0; j< JGG_SIZE; j++)
		{
			if (JGG_CONST_STRING[j] == data[i])
			{
				bFind = true;
			}
		}
		if (bFind == false)
		{
			return false;
		}

		//fuck
		for( k=0,j=0; j<JGG_SIZE; j++ )
		{
			x = (unsigned char) ( x + 1 )%JGG_SIZE;
			y = (unsigned char) ( y + rk.m[x] )%JGG_SIZE;

			if (x != y)
			{
				rk.m[x] ^= rk.m[y];
				rk.m[y] ^= rk.m[x];
				rk.m[x] ^= rk.m[y];
			}
			if( ++k >= ilen)
				k = 0;
		}

		//encrypt
		if (enc)
		{	
			for (j=0; j<JGG_SIZE; j++)
			{
				if (data[i] == rk.m[j])
				{
					break;
				}
			}
			data[i] = JGG_CONST_STRING[j];
		}
		//decrypt
		else
		{
			for (j=0; j<JGG_SIZE; j++)
			{
				if (data[i] == JGG_CONST_STRING[j])
				{
					break;
				}
			}
			data[i] = rk.m[j];
		}
	}
	rk.x = x;
	rk.y = y;

	return true;
}

std::string jggEncrypt(JGG_KEY &jk, const std::string &src, bool enc)
{
	auto ret = src;
	if (jggEncrypt(jk, (unsigned char *)ret.c_str(), (int)ret.length(), enc))
		return ret;
	return "";
}

int main()
{
	std::string src = "***hello github!!!***";
	auto dst = jggEncrypt(jggSetup("i am a key..."), src, true);
	printf("src:%s\n", src.c_str());
	printf("dst:%s\n", dst.c_str());
	printf("src:%s\n", jggEncrypt(jggSetup("i am a key..."), dst, false).c_str());

	return 0;
}