悲像之我

서비스는 기본적으로 SYSTEM 계정이다.

이 서비스가 어떠한 프로세스 (exe)를 실행시켜주게 되면,

계정이나 권한도 그대로 승계받게되어, SYSTEM 계정으로 실행이 된다.

하지만 SYSTEM 계정의 Service는 기본적으로 UI를 지원하지 않는다.

UI를 지원하려면 USER계정으로 실행이 되어야 하는데,

이 때, 서비스에서는 특정 프로세스(exe)를 실행시켜줄 때, 단순히 Process.Start()를 하게되면

SYSTEM 계정으로 실행되게 되고,....

웹상에 흔히 돌아디는 아래코드를 이용해서 USER권한으로 실행하게 된다.

(advapi32.dll 의 CreateProcessAsUser 함수를 이용하는 방법)

아래는 샘플들

public class ApplicationLoader
    {
        #region Structures

        [StructLayout(LayoutKind.Sequential)]
        public struct SECURITY_ATTRIBUTES
        {
            public int Length;
            public IntPtr lpSecurityDescriptor;
            public bool bInheritHandle;
        }

        [StructLayout(LayoutKind.Sequential)]
        public struct STARTUPINFO
        {
            public int cb;
            public String lpReserved;
            public String lpDesktop;
            public String lpTitle;
            public uint dwX;
            public uint dwY;
            public uint dwXSize;
            public uint dwYSize;
            public uint dwXCountChars;
            public uint dwYCountChars;
            public uint dwFillAttribute;
            public uint dwFlags;
            public short wShowWindow;
            public short cbReserved2;
            public IntPtr lpReserved2;
            public IntPtr hStdInput;
            public IntPtr hStdOutput;
            public IntPtr hStdError;
        }

        [StructLayout(LayoutKind.Sequential)]
        public struct PROCESS_INFORMATION
        {
            public IntPtr hProcess;
            public IntPtr hThread;
            public uint dwProcessId;
            public uint dwThreadId;
        }

        #endregion

        #region Enumerations

        enum TOKEN_TYPE : int
        {
            TokenPrimary = 1,
            TokenImpersonation = 2
        }

        enum SECURITY_IMPERSONATION_LEVEL : int
        {
            SecurityAnonymous = 0,
            SecurityIdentification = 1,
            SecurityImpersonation = 2,
            SecurityDelegation = 3,
        }

        #endregion

        #region Constants

        public const int TOKEN_DUPLICATE = 0x0002;
        public const uint MAXIMUM_ALLOWED = 0x2000000;
        public const int CREATE_NEW_CONSOLE = 0x00000010;

        public const int IDLE_PRIORITY_CLASS = 0x40;
        public const int NORMAL_PRIORITY_CLASS = 0x20;
        public const int HIGH_PRIORITY_CLASS = 0x80;
        public const int REALTIME_PRIORITY_CLASS = 0x100;

        #endregion

        #region Win32 API Imports

        [DllImport("kernel32.dll", SetLastError = true)]
        private static extern bool CloseHandle(IntPtr hSnapshot);

        [DllImport("kernel32.dll")]
        static extern uint WTSGetActiveConsoleSessionId();

        [DllImport("advapi32.dll", EntryPoint = "CreateProcessAsUser", SetLastError = true, CharSet = CharSet.Ansi, CallingConvention = CallingConvention.StdCall)]
        public extern static bool CreateProcessAsUser(IntPtr hToken, String lpApplicationName, String lpCommandLine, ref SECURITY_ATTRIBUTES lpProcessAttributes,
            ref SECURITY_ATTRIBUTES lpThreadAttributes, bool bInheritHandle, int dwCreationFlags, IntPtr lpEnvironment,
            String lpCurrentDirectory, ref STARTUPINFO lpStartupInfo, out PROCESS_INFORMATION lpProcessInformation);

        [DllImport("kernel32.dll")]
        static extern bool ProcessIdToSessionId(uint dwProcessId, ref uint pSessionId);

        [DllImport("advapi32.dll", EntryPoint = "DuplicateTokenEx")]
        public extern static bool DuplicateTokenEx(IntPtr ExistingTokenHandle, uint dwDesiredAccess,
            ref SECURITY_ATTRIBUTES lpThreadAttributes, int TokenType,
            int ImpersonationLevel, ref IntPtr DuplicateTokenHandle);

        [DllImport("kernel32.dll")]
        static extern IntPtr OpenProcess(uint dwDesiredAccess, bool bInheritHandle, uint dwProcessId);

        [DllImport("advapi32", SetLastError = true), SuppressUnmanagedCodeSecurityAttribute]
        static extern bool OpenProcessToken(IntPtr ProcessHandle, int DesiredAccess, ref IntPtr TokenHandle);

        #endregion

        static private void wirteFileTest(string orgmsg)
        {
            string msg = DateTime.Now.ToString("yy-MM-dd(ddd) HH:mm:ss") + " : " + orgmsg;

            string logfolder = AppDomain.CurrentDomain.BaseDirectory + @"\LOG\";
            if (Directory.Exists(logfolder) == false)
                Directory.CreateDirectory(logfolder);

            string today = DateTime.Today.ToString("yyyyMMdd");
            string filepath = logfolder + "Service_LOG_" + today + "-" + DateTime.Now.ToString("HH") + ".log";

            if (File.Exists(filepath) == false)
            {
                using (StreamWriter sw = File.CreateText(filepath))
                {
                    sw.WriteLine(msg);
                }
            }
            else
            {
                using (StreamWriter sw = File.AppendText(filepath))
                {
                    sw.WriteLine(msg);
                }

            }
        }

        /// <summary>
        /// Launches the given application with full admin rights, and in addition bypasses the Vista UAC prompt
        /// </summary>
        /// <param name="applicationName">The name of the application to launch</param>
        /// <param name="procInfo">Process information regarding the launched application that gets returned to the caller</param>
        /// <returns></returns>
        public static bool StartProcessAndBypassUAC(String applicationName, out PROCESS_INFORMATION procInfo)
        {
            uint winlogonPid = 0;
            IntPtr hUserTokenDup = IntPtr.Zero, hPToken = IntPtr.Zero, hProcess = IntPtr.Zero;
            procInfo = new PROCESS_INFORMATION();

            // obtain the currently active session id; every logged on user in the system has a unique session id
            uint dwSessionId = WTSGetActiveConsoleSessionId();

            // obtain the process id of the winlogon process that is running within the currently active session
            Process[] processes = Process.GetProcessesByName("winlogon");
            foreach (Process p in processes)
            {
                if ((uint)p.SessionId == dwSessionId)
                {
                    winlogonPid = (uint)p.Id;
                }
            }

            // obtain a handle to the winlogon process
            hProcess = OpenProcess(MAXIMUM_ALLOWED, false, winlogonPid);

            // obtain a handle to the access token of the winlogon process
            if (!OpenProcessToken(hProcess, TOKEN_DUPLICATE, ref hPToken))
            {
                CloseHandle(hProcess);
                return false;
            }

            wirteFileTest("1");

            // Security attibute structure used in DuplicateTokenEx and CreateProcessAsUser
            // I would prefer to not have to use a security attribute variable and to just 
            // simply pass null and inherit (by default) the security attributes
            // of the existing token. However, in C# structures are value types and therefore
            // cannot be assigned the null value.
            SECURITY_ATTRIBUTES sa = new SECURITY_ATTRIBUTES();
            sa.Length = Marshal.SizeOf(sa);


            // copy the access token of the winlogon process; the newly created token will be a primary token
            if (!DuplicateTokenEx(hPToken, MAXIMUM_ALLOWED, ref sa, (int)SECURITY_IMPERSONATION_LEVEL.SecurityIdentification, (int)TOKEN_TYPE.TokenPrimary, ref hUserTokenDup))
            {
                CloseHandle(hProcess);
                CloseHandle(hPToken);
                return false;
            }

            wirteFileTest("2");

            // By default CreateProcessAsUser creates a process on a non-interactive window station, meaning
            // the window station has a desktop that is invisible and the process is incapable of receiving
            // user input. To remedy this we set the lpDesktop parameter to indicate we want to enable user 
            // interaction with the new process.
            STARTUPINFO si = new STARTUPINFO();
            si.cb = (int)Marshal.SizeOf(si);
            si.lpDesktop = @"winsta0\default"; // interactive window station parameter; basically this indicates that the process created can display a GUI on the desktop

            // flags that specify the priority and creation method of the process
            int dwCreationFlags = NORMAL_PRIORITY_CLASS | CREATE_NEW_CONSOLE;

            // create a new process in the current user's logon session
            bool result = CreateProcessAsUser(hUserTokenDup,        // client's access token
                                            null,                   // file to execute
                                            applicationName,        // command line
                                            ref sa,                 // pointer to process SECURITY_ATTRIBUTES
                                            ref sa,                 // pointer to thread SECURITY_ATTRIBUTES
                                            false,                  // handles are not inheritable
                                            dwCreationFlags,        // creation flags
                                            IntPtr.Zero,            // pointer to new environment block 
                                            null,                   // name of current directory 
                                            ref si,                 // pointer to STARTUPINFO structure
                                            out procInfo            // receives information about new process
                                            );

            wirteFileTest("3");

            // invalidate the handles
            CloseHandle(hProcess);
            CloseHandle(hPToken);
            CloseHandle(hUserTokenDup);

            return result; // return the result
        }

    }

하지만 이럼에도 불구하고, 간혹 실행이 되지 않는 경우가 있는데.. 이는

실행시키려는 프로세스가 Listen 등을 수행하는 프로세스 일경우, 아래와 같이 팝업이 뜨게 되고,

이 허용을 안하게 되면, 실행이 되지 않는다.

위 정보에 대한 저장은 방화벽(디펜더)쪽에 저장된다.

그래도 안된다면....  윈도키 secpol (로컬보안정책) 들어가서
보안정책 - 로컬정책 - 보안옵션 들어가서
사용자계정컨트롤 관리승인모드에서 모든관리자실행옵션을 사용안함 해주어야한다

보안프로그램들이 이런 셋팅을 주로 건들지만, 저 셋팅의 기본값은

OS종류(home, pro 등)나 version 등에 따라 달라진다.