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

150 lines
4.1 KiB
C

#include <windows.h>
#include <stdbool.h>
#include "obfuscate.h"
#include "inject-library.h"
typedef HANDLE (WINAPI *create_remote_thread_t)(HANDLE, LPSECURITY_ATTRIBUTES,
SIZE_T, LPTHREAD_START_ROUTINE, LPVOID, DWORD, LPDWORD);
typedef BOOL (WINAPI *write_process_memory_t)(HANDLE, LPVOID, LPCVOID, SIZE_T,
SIZE_T*);
typedef LPVOID (WINAPI *virtual_alloc_ex_t)(HANDLE, LPVOID, SIZE_T, DWORD,
DWORD);
typedef BOOL (WINAPI *virtual_free_ex_t)(HANDLE, LPVOID, SIZE_T, DWORD);
int inject_library_obf(HANDLE process, const wchar_t *dll,
const char *create_remote_thread_obf, uint64_t obf1,
const char *write_process_memory_obf, uint64_t obf2,
const char *virtual_alloc_ex_obf, uint64_t obf3,
const char *virtual_free_ex_obf, uint64_t obf4,
const char *load_library_w_obf, uint64_t obf5)
{
int ret = INJECT_ERROR_UNLIKELY_FAIL;
DWORD last_error = 0;
bool success = false;
size_t written_size;
DWORD thread_id;
HANDLE thread;
size_t size;
void *mem;
/* -------------------------------- */
HMODULE kernel32 = GetModuleHandleW(L"KERNEL32");
create_remote_thread_t create_remote_thread;
write_process_memory_t write_process_memory;
virtual_alloc_ex_t virtual_alloc_ex;
virtual_free_ex_t virtual_free_ex;
FARPROC load_library_w;
create_remote_thread = get_obfuscated_func(kernel32,
create_remote_thread_obf, obf1);
write_process_memory = get_obfuscated_func(kernel32,
write_process_memory_obf, obf2);
virtual_alloc_ex = get_obfuscated_func(kernel32,
virtual_alloc_ex_obf, obf3);
virtual_free_ex = get_obfuscated_func(kernel32,
virtual_free_ex_obf, obf4);
load_library_w = get_obfuscated_func(kernel32,
load_library_w_obf, obf5);
/* -------------------------------- */
size = (wcslen(dll) + 1) * sizeof(wchar_t);
mem = virtual_alloc_ex(process, NULL, size, MEM_COMMIT,
PAGE_EXECUTE_READWRITE);
if (!mem) {
goto fail;
}
success = write_process_memory(process, mem, dll,
size, &written_size);
if (!success) {
goto fail;
}
thread = create_remote_thread(process, NULL, 0,
(LPTHREAD_START_ROUTINE)load_library_w, mem, 0,
&thread_id);
if (!thread) {
goto fail;
}
if (WaitForSingleObject(thread, 4000) == WAIT_OBJECT_0) {
DWORD code;
GetExitCodeThread(thread, &code);
ret = (code != 0) ? 0 : INJECT_ERROR_INJECT_FAILED;
SetLastError(0);
}
fail:
if (ret == INJECT_ERROR_UNLIKELY_FAIL) {
last_error = GetLastError();
}
if (thread) {
CloseHandle(thread);
}
if (mem) {
virtual_free_ex(process, mem, 0, MEM_RELEASE);
}
if (last_error != 0) {
SetLastError(last_error);
}
return ret;
}
/* ------------------------------------------------------------------------- */
typedef HHOOK (WINAPI *set_windows_hook_ex_t)(int, HOOKPROC, HINSTANCE, DWORD);
#define RETRY_INTERVAL_MS 500
#define TOTAL_RETRY_TIME_MS 4000
#define RETRY_COUNT (TOTAL_RETRY_TIME_MS / RETRY_INTERVAL_MS)
int inject_library_safe_obf(DWORD thread_id, const wchar_t *dll,
const char *set_windows_hook_ex_obf, uint64_t obf1)
{
HMODULE user32 = GetModuleHandleW(L"USER32");
set_windows_hook_ex_t set_windows_hook_ex;
HMODULE lib = LoadLibraryW(dll);
LPVOID proc;
HHOOK hook;
size_t i;
if (!lib || !user32) {
return INJECT_ERROR_UNLIKELY_FAIL;
}
#ifdef _WIN64
proc = GetProcAddress(lib, "dummy_debug_proc");
#else
proc = GetProcAddress(lib, "_dummy_debug_proc@12");
#endif
if (!proc) {
return INJECT_ERROR_UNLIKELY_FAIL;
}
set_windows_hook_ex = get_obfuscated_func(user32,
set_windows_hook_ex_obf, obf1);
hook = set_windows_hook_ex(WH_GETMESSAGE, proc, lib, thread_id);
if (!hook) {
return GetLastError();
}
/* SetWindowsHookEx does not inject the library in to the target
* process unless the event associated with it has occurred, so
* repeatedly send the hook message to start the hook at small
* intervals to signal to SetWindowsHookEx to process the message and
* therefore inject the library in to the target process. Repeating
* this is mostly just a precaution. */
for (i = 0; i < RETRY_COUNT; i++) {
Sleep(RETRY_INTERVAL_MS);
PostThreadMessage(thread_id, WM_USER + 432, 0, (LPARAM)hook);
}
return 0;
}