単純復号化

import android.util.Base64;



public class Simplede {

	public static byte[] doencrypt(byte[] data, byte[] keyData) {

		int keyIndex = 0;
		for (int x = 0; x < data.length; x++) {
			data[x] = (byte) (data[x] ^ keyData[keyIndex]);
			if (++keyIndex == keyData.length) {
				keyIndex = 0;
			}
		}
		return data;
	}
	public static String encrypt(String strOld, String strKey) {

		byte[] data=doencrypt(strOld.getBytes(), strKey.getBytes());
		
		
		return Base64.encodeToString(data, Base64.DEFAULT);
	}
	public static String decrypt(String strOld, String strKey) {

		byte[] mingwen=Base64.decode(strOld.getBytes(), Base64.DEFAULT);
		byte[] data=doencrypt(mingwen, strKey.getBytes());
				
		return new String(data);
	}

	public static void main(String[] args) {

		String key="10241314";
		String seed="test ";
		for(int i=0;i<30;i++)
		{
			seed=seed+i;
			System.out.println(seed);
			//  ：
			String data=encrypt(seed,key);
			System.out.println(data);
			//  ：
			System.out.println(decrypt(data,key));
		}
		
	}
}

public class SimpledeForCPP {

/*
#include <stdlib.h>
#include <conio.h>
#include <stdio.h>
#include <string.h>


unsigned char* myobfuscate(unsigned char *s) {
	unsigned char key, mod, len;
	int i;
	unsigned char* d;

	key = s[0];
	mod = 0x66;
	len = strlen((const char*)s);
	d = (unsigned char *)malloc(len + 1);

	// zero terminate the string
	memset(d, 0x00, len + 1);

	for (i = 0; i < len; i++) {
		d[i] = s[i] ^ mod;
	}
	d[len] = 0;
	return d;
}

// '\x12' , x, X

static unsigned char mystr[]="\xc\x7\x10\x7\x7\x8\x2\x14\x9\xf\x2";
static unsigned char mychinese[]="\xb0\xb6\xa8\xa2\x12\x3\x15\x12\xc\x7\x10\x7\x7\x8\x2\x14\x9\xf\x2\xa8\xb4\xa6\xd2\xb1\xb2\x2c\x7\x10\x7\x46\x5\x16\x16\xda\xb5\xa5\xba";


int main(int argc, char *argv[])
{
	printf("%s
",deobfuscate(proc_kallsyms));

	printf("%s
",myobfuscate(mystr));
	printf("%s
",myobfuscate(mychinese));

	getch();
	return 0;
}

 */

	public static void main(String[] args) throws Exception {

		StringBuffer sb=new StringBuffer();
		byte[] data=" testjavaandroid Java cpp ".getBytes("GBK");
		byte[] buffer=new byte[data.length];
		for (int x = 0; x < data.length; x++) {
			buffer[x] = (byte) (data[x] ^ 0x66);
			int v = buffer[x] & 0xFF;   
			sb.append("\\x"+Integer.toHexString(v));
			
		}
		//System.out.println(new String(buffer));
		System.out.println(sb.toString());
		
	}
}

char* simpleed(char *str,const char *pwd)
{
	int j0=0;
	int j=-1;
	int len=0;
	// 
	while(pwd[++j0]);
	len=strlen(str);
	char* code=new char[len+1];
	for (unsigned int i=0;i<strlen(str);i++)
	{	
		if(j>=j0)
		{
			j=0;
		}else{
			j++;
		}
		printf("index=%d
",j);
		code[i]=str[i]^pwd[j];/* fp2 */		

	}
	code[len]='\0';
	return code;
}

int main( int argc, char* argv[] )
{
	char* str="abcdefghijklmn test";

	const char *pwd="1024key";

	printf("%s
",str);

	str=simpleed(str,pwd);
	printf("%s
",str);
	OutputDebugStringA(str);

	str=simpleed(str,pwd);
	printf("%s
",str);
	OutputDebugStringA(str);


	getch();

	return 0;
}

char* simpleed(char *str,const char *pwd)
{
	int j0=0;
	int j=-1;
	int len=0;
	// 
	while(pwd[++j0]);
	len=strlen(str);
	char* code=new char[len+1];
	for (unsigned int i=0;i<len;i++)
	{	
		if(j>=j0)
		{
			j=0;
		}else{
			j++;
		}
		//printf("index=%d
",j);
		code[i]=str[i]^0x77;/* fp2 */		

	}
	code[len]='\0';
	return code;
}