BOOL DataCompare(BYTE *data, BYTE *sign, char *mask)
{
    for (; *mask; mask++, sign++, data++) {
        if (*mask == 'x' && *data != *sign) return FALSE;
    }

    return (*mask) == NULL;
}

DWORD ScanSignature(DWORD addr, DWORD size, BYTE *sign, char *mask)
{
    if (size == 0 || sign == nullptr || mask == nullptr) return 0;

    HANDLE hProc = GetCurrentProcess();
    if (hProc)
    {
        MEMORY_BASIC_INFORMATION mbi = { 0 };
        DWORD offset = 0;

        while (offset < size)
        {
            VirtualQueryEx(hProc, reinterpret_cast<LPCVOID>(addr + offset), &mbi, sizeof(MEMORY_BASIC_INFORMATION));
            if (mbi.State != MEM_FREE)
            {
                BYTE *buffer = new BYTE[mbi.RegionSize];
                ReadProcessMemory(hProc, mbi.BaseAddress, buffer, mbi.RegionSize, 0);
                for (SIZE_T i = 0; i < mbi.RegionSize; i++)
                {
                    if (DataCompare(buffer + i, sign, mask))
                    {
                        CloseHandle(hProc);
                        delete[] buffer;
                        return reinterpret_cast<DWORD>(mbi.BaseAddress) + i;
                    }
                }
                delete[] buffer;
            }
            offset += mbi.RegionSize;
        }
        CloseHandle(hProc);
    }

    return 0;
}