private static int StartProcessAsCurrentUser(string fileName, string arguments, string workingDirectory)
{
var procInfo = new PROCESS_INFORMATION();
var userToken = IntPtr.Zero;
var primaryToken = IntPtr.Zero;
var ptrEnvironment = IntPtr.Zero;
try
{
var activeUserSessionId = ProcessNativeMethods.WTSGetActiveConsoleSessionId();
if (activeUserSessionId == 0xFFFFFFFF)
{
var error = Marshal.GetLastWin32Error();
var message = string.Format("StartProcessAsCurrentUser: WTSGetActiveConsoleSessionId failed, Error: {0}", error);
throw new Win32Exception(error, message);
}
var buffer = IntPtr.Zero;
var bytesReturned = (UInt32)0;
if (!ProcessNativeMethods.WTSQuerySessionInformation(IntPtr.Zero, (int)activeUserSessionId, WTS_INFO_CLASS.WTSUserName, out buffer, out bytesReturned))
{
var error = Marshal.GetLastWin32Error();
//On earlier operating systems from Vista, when no one is logged in, you get RPC_S_INVALID_BINDING which is ok, we just won't impersonate
if (error != ProcessNativeConstants.RPC_S_INVALID_BINDING)
{
var message = string.Format("StartProcessAsCurrentUser: WTSQuerySessionInformation failed, Error: {0}", error);
throw new Win32Exception(error, message);
}
//No one logged in so let's just do this the simple way
return(StartProcess(fileName, arguments, workingDirectory));
}
var activeUserName = Marshal.PtrToStringAnsi(buffer);
ProcessNativeMethods.WTSFreeMemory(buffer);
//We are supposedly running as a service so we're going to be running in session 0 so get a user token from the active user session
if (!ProcessNativeMethods.WTSQueryUserToken(activeUserSessionId, out userToken))
{
var error = Marshal.GetLastWin32Error();
var message = string.Format("StartProcessAsCurrentUser: WTSQueryUserToken failed, Error: {0}", error);
throw new Win32Exception(error, message);
}
// Convert the impersonation token to a primary token
if (!ProcessNativeMethods.DuplicateTokenEx(userToken, TokenAccess.TOKEN_ASSIGN_PRIMARY | TokenAccess.TOKEN_ALL_ACCESS, IntPtr.Zero, SECURITY_IMPERSONATION_LEVEL.SecurityImpersonation, TOKEN_TYPE.TokenPrimary, out primaryToken))
{
var error = Marshal.GetLastWin32Error();
var message = string.Format("StartProcessAsCurrentUser: DuplicateTokenEx failed, Error: {0}", error);
throw new Win32Exception(error, message);
}
//Create an appropriate environment block for this user token (if we have one)
if (!ProcessNativeMethods.CreateEnvironmentBlock(out ptrEnvironment, primaryToken, false))
{
var error = Marshal.GetLastWin32Error();
var message = string.Format("StartProcessAsCurrentUser: CreateEnvironmentBlock failed, Error: {0}", error);
throw new Win32Exception(error, message);
}
var profileInfo = new PROFILEINFO();
profileInfo.dwSize = Marshal.SizeOf(profileInfo);
profileInfo.lpUserName = activeUserName;
//Remember, sometimes nobody is logged in (especially when we're set to Automatically startup)
if (!ProcessNativeMethods.LoadUserProfile(primaryToken, ref profileInfo))
{
var error = Marshal.GetLastWin32Error();
var message = string.Format("StartProcessAsCurrentUser: LoadUserProfile failed, Error: {0}", error);
throw new Win32Exception(error, message);
}
var startInfo = new STARTUPINFO();
startInfo.cb = Marshal.SizeOf(startInfo);
//DO NOT set this to "winsta0\\default" (even though many online resources say to do so)
//startInfo.lpDesktop = string.Empty;
var commandLine = "\"" + fileName + "\"";
commandLine = !string.IsNullOrEmpty(arguments) ? (commandLine + " " + arguments) : commandLine;
if (!ProcessNativeMethods.CreateProcessAsUser(primaryToken, null, commandLine, IntPtr.Zero, IntPtr.Zero, false, CreationFlags.CREATE_NO_WINDOW | CreationFlags.NORMAL_PRIORITY_CLASS | CreationFlags.CREATE_UNICODE_ENVIRONMENT, ptrEnvironment, workingDirectory, ref startInfo, ref procInfo))
{
var error = Marshal.GetLastWin32Error();
var message = string.Format("StartProcessAsCurrentUser: CreateProcessAsUser failed, Error: {0}", error);
throw new Win32Exception(error, message);
}
return(procInfo.dwProcessID);
}
finally
{
if (userToken != IntPtr.Zero)
{
ProcessNativeMethods.CloseHandle(userToken);
}
if (primaryToken != IntPtr.Zero)
{
ProcessNativeMethods.CloseHandle(primaryToken);
}
if (ptrEnvironment != IntPtr.Zero)
{
ProcessNativeMethods.DestroyEnvironmentBlock(ptrEnvironment);
}
if (procInfo.hProcess != IntPtr.Zero)
{
ProcessNativeMethods.CloseHandle(procInfo.hProcess);
}
if (procInfo.hThread != IntPtr.Zero)
{
ProcessNativeMethods.CloseHandle(procInfo.hThread);
}
}
}
