obs-studio/plugins/win-capture/obfuscate.c

40 lines
811 B
C

#ifdef _MSC_VER
#pragma warning(disable : 4152) /* casting func ptr to void */
#endif
#include <stdbool.h>
#include <windows.h>
#include "obfuscate.h"
#define LOWER_HALFBYTE(x) ((x)&0xF)
#define UPPER_HALFBYTE(x) (((x) >> 4) & 0xF)
static void deobfuscate_str(char *str, uint64_t val)
{
uint8_t *dec_val = (uint8_t *)&val;
int i = 0;
while (*str != 0) {
int pos = i / 2;
bool bottom = (i % 2) == 0;
uint8_t *ch = (uint8_t *)str;
uint8_t xor = bottom ? LOWER_HALFBYTE(dec_val[pos])
: UPPER_HALFBYTE(dec_val[pos]);
*ch ^= xor;
if (++i == sizeof(uint64_t) * 2)
i = 0;
str++;
}
}
void *get_obfuscated_func(HMODULE module, const char *str, uint64_t val)
{
char new_name[128];
strcpy(new_name, str);
deobfuscate_str(new_name, val);
return GetProcAddress(module, new_name);
}