从运行进程注入DLL后弹出

Question

我编写了这个函数来将DLL注入到运行进程中:

DLL_Results CDLL_Loader::InjectDll()
{
    DWORD ThreadTeminationStatus;
    LPVOID VirtualMem;
    HANDLE hProcess, hRemoteThread;
    HMODULE hModule;

    if (!isInit())
        return NOT_INIT;

    if (isInjected())
        return DLL_ALREADY_HOOKED;

    hProcess = OpenProcess(PROCESS_ALL_ACCESS, FALSE, ProcessID);
    if (hProcess == NULL)
        return PROCESS_ERROR_OPEN;

    VirtualMem = VirtualAllocEx (hProcess, NULL, strlen(DllFilePath), MEM_COMMIT | MEM_RESERVE, PAGE_READWRITE);
    if (VirtualMem == NULL)
        return PROCESS_ERRORR_VALLOC;

    if (WriteProcessMemory(hProcess, (LPVOID)VirtualMem, DllFilePath, strlen(DllFilePath), NULL) == 0)
    {
        VirtualFreeEx(hProcess, NULL, (size_t)strlen(DllFilePath), MEM_RESERVE|MEM_COMMIT);
        CloseHandle(hProcess); 
        return PROCESS_ERROR_WRITE;
    }

    hModule = GetModuleHandle(L"kernel32.dll");
    hRemoteThread = CreateRemoteThread(hProcess, NULL, 0, 
                        (LPTHREAD_START_ROUTINE)GetProcAddress(hModule, "LoadLibraryA"),
                          (LPVOID)VirtualMem, 0, NULL);

    if (hRemoteThread == NULL)
    {
        FreeLibrary(hModule);
        VirtualFreeEx(hProcess, NULL, (size_t)strlen(DllFilePath), MEM_RESERVE | MEM_COMMIT);
        CloseHandle(hProcess); 
        return PROCESS_ERROR_CREATE_RTHREAD;
    }

    WaitForSingleObject(hRemoteThread, INFINITE);
    GetExitCodeThread(hRemoteThread, &ThreadTeminationStatus);
    FreeLibrary(hModule);

    VirtualFreeEx(hProcess, NULL, (size_t)strlen(DllFilePath), MEM_RESERVE | MEM_COMMIT);
    CloseHandle(hRemoteThread);
    CloseHandle(hProcess); 
    injected = true;
    return DLLHOOK_OK;
}

它工作得很好,但是当我试图弹出dll时我无法找到关于取消的信息..我正在尝试建立一些功能来做到这一点我认为我很接近这是我到目前为止所拥有的:

那是正确的方法吗？如果是这样我应该在virtualMem的createRemoteThread instade中传递什么参数(在注入函数中使用)...

DLL_Results CDLL_Loader::EjectDll()
{
    DWORD ThreadTeminationStatus;
    HANDLE hProcess, hRemoteThread;
    HMODULE hModule;

    if (isInjected())
        return DLLEJECT_OK;

    hProcess = OpenProcess(PROCESS_ALL_ACCESS, FALSE, ProcessID);
    if (hProcess == NULL)
        return PROCESS_ERROR_OPEN;

    hModule = GetModuleHandle(L"kernel32.dll");
    hRemoteThread = CreateRemoteThread(hProcess, NULL, 0, 
                        (LPTHREAD_START_ROUTINE)GetProcAddress(hModule, "FreeLibrary"),
                          /*(LPVOID)VirtualMem <- What do i need to send here?*/, 0, NULL);

    if (hRemoteThread != NULL)
    {
        WaitForSingleObject(hRemoteThread, INFINITE);
        GetExitCodeThread(hRemoteThread, &ThreadTeminationStatus);
    }

    CloseHandle(hRemoteThread);
    CloseHandle(hProcess); 
    injected = false;
    return DLLEJECT_OK;
}

Answer 1

在32位系统上,ThreadTeminationStatusafter 的值GetExitCodeThread包含LoadLibraryA远程进程中的返回值.这是新加载的dll的模块句柄.您可以将它用作FreeLibrary远程线程中的参数.

如果要在64位Windows上使用该代码,则线程退出代码将被截断为32位DWORD,因此无法使用.必须创建在远程进程一个可调用的例程(如Necrolis建议的)或诉诸经由PSAPI或找到DLL的模块基座TOOLHELP API( ,CreateToolhelp32Snapshot,).Module32FirstModule32Next

Answer 2

你需要传递HANDLE你注入的dll,否则你可以传递它,VirtualMem但是你的远程线程例程需要是:

DWORD WINAPI UnloadDll(void* pMem)
{
    FreeLibrary(GetModuleHandleA((const char*)pMem));
    return 0;
}

但是,通常您注入的DLL应该在主机关闭时手动或自动卸载(请参阅DllMain工作原理).