obs-studio/plugins/win-capture/inject-helper/inject-helper.c

#include <stdio.h>
#include <stdlib.h>
#include <wchar.h>
#include <windows.h>
#include <shellapi.h>
#include <stdbool.h>
#ifdef OBS_LEGACY
#include "../../../libobs/util/windows/obfuscate.h"
#include "../inject-library.h"
#else
#include <util/windows/obfuscate.h>
#include <inject-library.h>
#endif

#if defined(_MSC_VER) && !defined(inline)
#define inline __inline
#endif

static void load_debug_privilege(void)
{
	const DWORD flags = TOKEN_ADJUST_PRIVILEGES | TOKEN_QUERY;
	TOKEN_PRIVILEGES tp;
	HANDLE token;
	LUID val;

	if (!OpenProcessToken(GetCurrentProcess(), flags, &token)) {
		return;
	}

	if (!!LookupPrivilegeValue(NULL, SE_DEBUG_NAME, &val)) {
		tp.PrivilegeCount = 1;
		tp.Privileges[0].Luid = val;
		tp.Privileges[0].Attributes = SE_PRIVILEGE_ENABLED;

		AdjustTokenPrivileges(token, false, &tp, sizeof(tp), NULL, NULL);
	}

	CloseHandle(token);
}

static inline HANDLE open_process(DWORD desired_access, bool inherit_handle, DWORD process_id)
{
	HANDLE(WINAPI * open_process_proc)(DWORD, BOOL, DWORD);
	open_process_proc = ms_get_obfuscated_func(GetModuleHandleW(L"KERNEL32"), "HxjcQrmkb|~", 0xc82efdf78201df87);

	return open_process_proc(desired_access, inherit_handle, process_id);
}

static inline int inject_library(HANDLE process, const wchar_t *dll)
{
	return inject_library_obf(process, dll, "E}mo|d[cefubWk~bgk", 0x7c3371986918e8f6, "Rqbr`T{cnor{Bnlgwz",
				  0x81bf81adc9456b35, "]`~wrl`KeghiCt", 0xadc6a7b9acd73c9b, "Zh}{}agHzfd@{",
				  0x57135138eb08ff1c, "DnafGhj}l~sX", 0x350bfacdf81b2018);
}

static inline int inject_library_safe(DWORD thread_id, const wchar_t *dll)
{
	return inject_library_safe_obf(thread_id, dll, "[bs^fbkmwuKfmfOvI", 0xEAD293602FCF9778ULL);
}

static inline int inject_library_full(DWORD process_id, const wchar_t *dll)
{
	HANDLE process = open_process(PROCESS_ALL_ACCESS, false, process_id);
	int ret;

	if (process) {
		ret = inject_library(process, dll);
		CloseHandle(process);
	} else {
		ret = INJECT_ERROR_OPEN_PROCESS_FAIL;
	}

	return ret;
}

static int inject_helper(wchar_t *argv[], const wchar_t *dll)
{
	DWORD id;
	DWORD use_safe_inject;

	use_safe_inject = wcstol(argv[2], NULL, 10);

	id = wcstol(argv[3], NULL, 10);
	if (id == 0) {
		return INJECT_ERROR_INVALID_PARAMS;
	}

	return use_safe_inject ? inject_library_safe(id, dll) : inject_library_full(id, dll);
}

int main(void)
{
	wchar_t dll_path[MAX_PATH];
	LPWSTR pCommandLineW;
	int argc;
	LPWSTR *argv;
	int ret = INJECT_ERROR_INVALID_PARAMS;

	SetErrorMode(SEM_FAILCRITICALERRORS);
	load_debug_privilege();

	pCommandLineW = GetCommandLineW();
	argv = CommandLineToArgvW(pCommandLineW, &argc);
	if (argv) {
		if (argc == 4) {
			if (GetModuleFileNameW(NULL, dll_path, MAX_PATH))
				ret = inject_helper(argv, argv[1]);
		}

		LocalFree(argv);
	}

	return ret;
}