c++ - Windows下多个用户登录时如何获取活动用户？

Question

假设当前有多个用户登录 Windows。说，user1登录，然后switch user登录user2，（不user1注销）。假设有一个应用程序在用户登录时运行。有两个用户user1并以活动用户身份user2登录user2，并且有两个应用程序。

我的问题是：应用程序如何知道其对应的用户是否处于活动状态？即，user2域中的应用程序确定其用户处于活动状态，而user1域中的应用程序确定其用户当前处于非活动状态。谢谢！

Answer 1

您可以调用WTSGetActiveConsoleSessionId以获取当前在物理控制台上处于活动状态的终端服务（又名“快速用户切换”又名“远程桌面”）会话 ID。

您可以调用WTSQuerySessionInformationwithWTS_CURRENT_SESSION获取会话标识符和WTSSessionId获取WTSInfoClass当前进程的终端服务会话 ID。

如果活动会话ID和当前进程会话ID相同，则当前进程对应的用户在物理控制台上具有活动会话。

如果您想知道当前进程正在运行的会话是否处于活动状态（但不一定在物理控制台上），您可以改为WTSConnectState使用WTSQuerySessionInformation.

Answer 2

WTSGetActiveConsoleSessionId() 从 Windows 服务运行时实际上可能返回会话 0。如果您需要从 Windows 服务执行此操作，则需要枚举所有会话并找到连接的会话，然后从中获取用户。

下面的代码做的远不止这些，包括模拟该用户并以该用户身份运行一个进程，所有这些都来自 Windows 服务，但如果您只对用户名感兴趣，请查找调用 WTSQuerySessionInformation() 函数的第二个实例.

//Function to run a process as active user from windows service
void ImpersonateActiveUserAndRun(WCHAR* path, WCHAR* args)
{
    DWORD session_id = -1;
    DWORD session_count = 0;

    WTS_SESSION_INFOA *pSession = NULL;


    if (WTSEnumerateSessions(WTS_CURRENT_SERVER_HANDLE, 0, 1, &pSession, &session_count))
    {
        //log success
    }
    else
    {
        //log error
        return;
    }

    for (int i = 0; i < session_count; i++)
    {
        session_id = pSession[i].SessionId;

        WTS_CONNECTSTATE_CLASS wts_connect_state = WTSDisconnected;
        WTS_CONNECTSTATE_CLASS* ptr_wts_connect_state = NULL;

        DWORD bytes_returned = 0;
        if (::WTSQuerySessionInformation(
            WTS_CURRENT_SERVER_HANDLE,
            session_id,
            WTSConnectState,
            reinterpret_cast<LPTSTR*>(&ptr_wts_connect_state),
            &bytes_returned))
        {
            wts_connect_state = *ptr_wts_connect_state;
            ::WTSFreeMemory(ptr_wts_connect_state);
            if (wts_connect_state != WTSActive) continue;
        }
        else
        {
            //log error
            continue;
        }

        HANDLE hImpersonationToken;

        if (!WTSQueryUserToken(session_id, &hImpersonationToken))
        {
            //log error
            continue;
        }


        //Get real token from impersonation token
        DWORD neededSize1 = 0;
        HANDLE *realToken = new HANDLE;
        if (GetTokenInformation(hImpersonationToken, (::TOKEN_INFORMATION_CLASS) TokenLinkedToken, realToken, sizeof(HANDLE), &neededSize1))
        {
            CloseHandle(hImpersonationToken);
            hImpersonationToken = *realToken;
        }
        else
        {
            //log error
            continue;
        }


        HANDLE hUserToken;

        if (!DuplicateTokenEx(hImpersonationToken,
            //0,
            //MAXIMUM_ALLOWED,
            TOKEN_ASSIGN_PRIMARY | TOKEN_ALL_ACCESS | MAXIMUM_ALLOWED,
            NULL,
            SecurityImpersonation,
            TokenPrimary,
            &hUserToken))
        {
            //log error
            continue;
        }

        // Get user name of this process
        //LPTSTR pUserName = NULL;
        WCHAR* pUserName;
        DWORD user_name_len = 0;

        if (WTSQuerySessionInformationW(WTS_CURRENT_SERVER_HANDLE, session_id, WTSUserName, &pUserName, &user_name_len))
        {
            //log username contained in pUserName WCHAR string
        }

        //Free memory                         
        if (pUserName) WTSFreeMemory(pUserName);

        ImpersonateLoggedOnUser(hUserToken);

        STARTUPINFOW StartupInfo;
        GetStartupInfoW(&StartupInfo);
        StartupInfo.cb = sizeof(STARTUPINFOW);
        //StartupInfo.lpDesktop = "winsta0\\default";

        PROCESS_INFORMATION processInfo;

        SECURITY_ATTRIBUTES Security1;
        Security1.nLength = sizeof SECURITY_ATTRIBUTES;

        SECURITY_ATTRIBUTES Security2;
        Security2.nLength = sizeof SECURITY_ATTRIBUTES;

        void* lpEnvironment = NULL;

        // Get all necessary environment variables of logged in user
        // to pass them to the new process
        BOOL resultEnv = CreateEnvironmentBlock(&lpEnvironment, hUserToken, FALSE);
        if (!resultEnv)
        {
            //log error
            continue;
        }

        WCHAR PP[1024]; //path and parameters
        ZeroMemory(PP, 1024 * sizeof WCHAR);
        wcscpy(PP, path);
        wcscat(PP, L" ");
        wcscat(PP, args);

        // Start the process on behalf of the current user 
        BOOL result = CreateProcessAsUserW(hUserToken, 
            NULL,
            PP,
            //&Security1,
            //&Security2,
            NULL,
            NULL,
            FALSE, 
            NORMAL_PRIORITY_CLASS | CREATE_NEW_CONSOLE,
            //lpEnvironment,
            NULL,
            //"C:\\ProgramData\\some_dir",
            NULL,
            &StartupInfo,
            &processInfo);

        if (!result)
        {
            //log error
        }
        else
        {
            //log success
        }

        DestroyEnvironmentBlock(lpEnvironment);

        CloseHandle(hImpersonationToken);
        CloseHandle(hUserToken);
        CloseHandle(realToken);

        RevertToSelf();
    }

    WTSFreeMemory(pSession);
}