XOR encryptation looks cool as well
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#define ENCRYPT(a,b) (encrypt_decrypt (a, b))
#define DECRYPT(a,b) (encrypt_decrypt (a, b))
signed char *
encrypt_decrypt (char *str, char *key)
{
char *crp_str, *addr;
crp_str = addr = (char *) malloc (strlen (str));
if (crp_str == 0)
return (char *)-1;
for (; *str;
str++, key++, crp_str++)
*crp_str = *str ^ *key;
*crp_str = '\0';
return addr;
}
int
main (void)
{
char *str;
str = ENCRYPT ("Hello World", "Im nice guy");
printf ("%s\n", DECRYPT (str, "Im nice guy"));
return 0;
}