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C# - How to Authenticate with server dinamically

I need to check if service "Advice" has its status running on said server. I made a method that does just that:
public static bool CheckServicesFromServer(string pServicos)
{
ServiceController service = new ServiceController();
List<string> Servicos = pServicos.Split(',').Select(p => p.Trim()).ToList();
if (Config.BaseLogin == BasesSistema.QualityLogin)
service.MachineName = "quality";
if (Config.BaseLogin == BasesSistema.TS02Login)
service.MachineName = "ts02";
if (Config.BaseLogin == BasesSistema.TS03Login)
service.MachineName = "ts03";
if (Config.BaseLogin == BasesSistema.LocalHost)
service.MachineName = Environment.MachineName;
try
{
foreach (var item in Servicos)
{
service.ServiceName = item;
if ((service.Status.Equals(ServiceControllerStatus.Stopped)) || (service.Status.Equals(ServiceControllerStatus.StopPending)))
{
File.AppendAllText(StatusLog.StatusLocation, "O servico " + service.ServiceName + " está parado. a Regra não será gerada.");
throw new Exception();
}
if (service.Status.Equals(ServiceControllerStatus.Running))
{
File.AppendAllText(StatusLog.StatusLocation, "O serviço " + service.ServiceName + "está rodando perfeitamente.");
}
}
}
catch (Exception e)
{
Log.WriteErrorLog(e.Message);
throw new Exception(e.Message);
}
return true;
}
The thing is, when I run the test, it says "Access Denied", and throws an exception. When I add my user (The user from the computer which is running the application) as an Adm at the server, it runs fine.
Is there a way to authenticate my computer so it can have permission to access the server and check its service status?

Thanks to Krik, I found the solution. It's as simple as addind this class:
using System;
using System.Security.Principal;
using System.Runtime.InteropServices;
using System.Security.Permissions;
public class ImpersonateUser
{
[DllImport("advapi32.dll", SetLastError = true)]
public static extern bool LogonUser(
String lpszUsername,
String lpszDomain,
String lpszPassword,
int dwLogonType,
int dwLogonProvider,
ref IntPtr phToken);
[DllImport("kernel32.dll", CharSet = CharSet.Auto)]
public extern static bool CloseHandle(IntPtr handle);
private static IntPtr tokenHandle = new IntPtr(0);
private static WindowsImpersonationContext impersonatedUser;
// If you incorporate this code into a DLL, be sure to demand that it
// runs with FullTrust.
[PermissionSetAttribute(SecurityAction.Demand, Name = "FullTrust")]
public void Impersonate(string domainName, string userName, string password)
{
//try
{
// Use the unmanaged LogonUser function to get the user token for
// the specified user, domain, and password.
const int LOGON32_PROVIDER_DEFAULT = 0;
// Passing this parameter causes LogonUser to create a primary token.
const int LOGON32_LOGON_INTERACTIVE = 2;
tokenHandle = IntPtr.Zero;
// ---- Step - 1
// Call LogonUser to obtain a handle to an access token.
bool returnValue = LogonUser(
userName,
domainName,
password,
LOGON32_LOGON_INTERACTIVE,
LOGON32_PROVIDER_DEFAULT,
ref tokenHandle); // tokenHandle - new security token
if (false == returnValue)
{
int ret = Marshal.GetLastWin32Error();
throw new System.ComponentModel.Win32Exception(ret);
}
// ---- Step - 2
WindowsIdentity newId = new WindowsIdentity(tokenHandle);
// ---- Step - 3
{
impersonatedUser = newId.Impersonate();
}
}
}
// Stops impersonation
public void Undo()
{
impersonatedUser.Undo();
// Free the tokens.
if (tokenHandle != IntPtr.Zero)
{
CloseHandle(tokenHandle);
}
}
internal void Impersonate()
{
throw new NotImplementedException();
}
}
And I Just had to call it like this:
public static bool CheckServicesFromServer(string pServicos)
{
ImpersonateUser Iu = new ImpersonateUser();
ServiceController service = new ServiceController();
List<string> Servicos = pServicos.Split(',').Select(p => p.Trim()).ToList();
if (Config.BaseLogin == BasesSistema.QualityLogin)
service.MachineName = "quality";
if (Config.BaseLogin == BasesSistema.TS02Login)
service.MachineName = "ts02";
if (Config.BaseLogin == BasesSistema.TS03Login)
service.MachineName = "ts03";
if (Config.BaseLogin == BasesSistema.LocalHost)
service.MachineName = Environment.MachineName;
Iu.Impersonate(Config.Dominio, Config.LoginMaster, Config.SenhaMaster);
try
{
foreach (var item in Servicos)
{
service.ServiceName = item;
if ((service.Status.Equals(ServiceControllerStatus.Stopped)) || (service.Status.Equals(ServiceControllerStatus.StopPending)))
{
Flag = true;
File.AppendAllText(StatusLog.StatusLocation, "O servico " + service.ServiceName + " está parado. a Regra não será gerada. <br />");
throw new Exception();
}
if (service.Status.Equals(ServiceControllerStatus.Running))
{
File.AppendAllText(StatusLog.StatusLocation, "O serviço " + service.ServiceName + " está rodando perfeitamente. <br />");
}
}
Iu.Undo();
}
catch
{
Iu.Undo();
Log.WriteErrorLog("Não é possível abrir o Gerenciador de Controle de Serviços no Computador '" + service.MachineName + "'. <br />");
return false;
}
return true;
}
My Config Class holds the information of the Domain, User and PassWord, and it worked perfectly.

Does Marshal.PtrToStringAnsi not working in windows service?

I have written a dll which call windows spooler api to get printer name and printer driver name, it works fine in console application. However, I got nothing when I call the dll in windows services application.
Here is my dll source code(i.e. printerUtility):
PRINTER_ENUM_LOCAL = 0x00000002,
PRINTER_ENUM_CONNECTIONS = 0x00000004,
public ArrayList getAllLocalPrinterInfo(LogWriter logger)
{
ArrayList printerInfoList = getAllLocalPrinterInfoV2(PrinterEnumFlags.PRINTER_ENUM_LOCAL | PrinterEnumFlags.PRINTER_ENUM_CONNECTIONS);
foreach (PrinterInfoV2 printerInfo in printerInfoList)
{
logger.write("In dll Printer Name pointer:" + printerInfo.pPrinterName+"\nIn dll Printer Name:" + Marshal.PtrToStringAnsi(printerInfo.pPrinterName));
logger.write("In dll Driver Name pointer:" + printerInfo.pDriverName+"\nIn dll Driver Name:" + Marshal.PtrToStringAnsi(printerInfo.pDriverName));
}
//return allLocalPrinterInfo;
return printerInfoList;
}
public ArrayList getAllLocalPrinterInfoV2(PrinterEnumFlags Flags)
{
return enumPrinters(Flags, 2);
}
private ArrayList enumPrinters(PrinterEnumFlags Flags, UInt32 level)
{
bool result;
ArrayList printerInfo = new ArrayList();
UInt32 returned, needed = 0;
UInt32 flags = Convert.ToUInt32(Flags);
//find required size for the buffer
result = EnumPrinters(flags, null, level, IntPtr.Zero, 0, out needed, out returned);
if (Marshal.GetLastWin32Error() != Convert.ToUInt32(CredUIReturnCodes.ERROR_INSUFFICIENT_BUFFER))
{
throw new Exception("EnumPrinters 1 failure, error code=" + Marshal.GetLastWin32Error());
}
else
{
IntPtr buffer = Marshal.AllocHGlobal((int)needed);
result = EnumPrinters(flags, null, level, buffer, needed, out needed, out returned);
if (result)
{
if ((level > 0) || (level < 5))
{
Type type = typeof(PrinterInfoV1);
switch (level)
{
case 1:
type = typeof(PrinterInfoV1);
break;
case 2:
type = typeof(PrinterInfoV2);
break;
case 3:
type = typeof(PrinterInfoV3);
break;
case 4:
type = typeof(PrinterInfoV4);
break;
}
int offset = buffer.ToInt32();
int increment = Marshal.SizeOf(type);
for (int i = 0; i < returned; i++)
{
printerInfo.Add(Marshal.PtrToStructure(new IntPtr(offset), type));
offset += increment;
}
Marshal.FreeHGlobal(buffer);
return printerInfo;
}
else
{
Marshal.FreeHGlobal(buffer);
throw new Exception("The value of level is out of range");
}
}
else
{
Marshal.FreeHGlobal(buffer);
throw new Exception("EnumPrinters 2 failure, error code=" + Marshal.GetLastWin32Error());
}
}
}
[DllImport("winspool.drv", SetLastError = true)]
static extern bool EnumPrinters([InAttribute()] UInt32 Flags,
[InAttribute()] string pPrinterName,
[InAttribute()] UInt32 Level,
[OutAttribute()] IntPtr pPrinter,
[InAttribute()] UInt32 cbBuf,
[OutAttribute()] out UInt32 pcbNeeded,
[OutAttribute()] out UInt32 pcReturned);
The LogWriter Source code:
public class LogWriter
{
EventLog eventLog = null;
public LogWriter(System.Diagnostics.EventLog elog)
{
this.eventLog = elog;
}
public void write(String msg)
{
if (eventLog != null)
{
eventLog.WriteEntry(msg);
}
}
}
Here is services source code:
protected override void OnStart(string[] args)
{
serviceStatus.dwWaitHint = 100000;
serviceStatus.dwCurrentState = ServiceState.SERVICE_START_PENDING;
SetServiceStatus(this.ServiceHandle, ref serviceStatus);
printerMonitorList = new ArrayList();
try
{
ArrayList printerInfoList = printerUtility.getAllLocalPrinterInfo(logger);
foreach (PrinterInfoV2 printerInfo in printerInfoList)
{
logger.write("In service Printer Name pointer:" + printerInfo.pPrinterName+"\nIn service Printer Name:" + Marshal.PtrToStringAnsi(printerInfo.pPrinterName));
logger.write("In service Driver Name pointer:" + printerInfo.pDriverName+"\nIn service Driver Name:" + Marshal.PtrToStringAnsi(printerInfo.pDriverName));
}
serviceStatus.dwCurrentState = ServiceState.SERVICE_RUNNING;
SetServiceStatus(this.ServiceHandle, ref serviceStatus);
logger.write(this.ServiceName + " Has Been Started");
}
catch (Exception err)
{
logger.write("Print Alert Service cannot be started:"+err.Message);
}
In event viewer, I got an empty string for both printer name and printer driver name.
However, I found that the dll return a pointer for both printer name and printer driver name. Therefore, I suspect whether the Marshal.PtrToStringAnsi function not working in window services environment.

C# Access a local folder with admin account credentials

I have two user accounts in my computer
User 1 (regular user)
Admin
Now I have folder "e:\Folder1" for which only Admin account has full access. User ! cannot access the folder.
I have a WPF Application Where It would run only within the User 1 account. I want the user 1 to user the wpf application to access "Folder1".
I want to know how to do it using C#.
I tried the following it doesnt work.
NetworkCredential theNetworkCredential = new NetworkCredential(#"admin", "pass");
CredentialCache theNetCache = new CredentialCache();
theNetCache.Add(new Uri(#"E:\SDAVideo"), "Basic", theNetworkCredential);
string[] theFolders = Directory.GetDirectories(#"E:\SDAVideo");
Here is what I have tried.
Using following code I am able to get the Windows of Identity of Admin user account
SafeTokenHandle safeTokenHandle;
try
{
const int LOGON32_PROVIDER_DEFAULT = 0;
//This parameter causes LogonUser to create a primary token.
const int LOGON32_LOGON_INTERACTIVE = 2;
// Call LogonUser to obtain a handle to an access token.
bool returnValue = LogonUser("admin", "", "pass",
LOGON32_LOGON_INTERACTIVE, LOGON32_PROVIDER_DEFAULT,
out safeTokenHandle);
if (false == returnValue)
{
int ret = Marshal.GetLastWin32Error();
Debug.Write("\nLogonUser failed with error code : " + ret);
throw new System.ComponentModel.Win32Exception(ret);
}
using (safeTokenHandle)
{
Debug.Write("\nDid LogonUser Succeed? " + (returnValue ? "Yes" : "No"));
Debug.Write("\nValue of Windows NT token: " + safeTokenHandle);
// Check the identity.
Debug.Write("\nBefore impersonation: "
+ WindowsIdentity.GetCurrent().Name);
Debug.Write("\nWriteAccess before: " + DirectoryHasPermission(#"E:\SDAVideo", WindowsIdentity.GetCurrent(), FileSystemRights.Write));
// Use the token handle returned by LogonUser.
using (WindowsImpersonationContext impersonatedUser = WindowsIdentity.Impersonate(safeTokenHandle.DangerousGetHandle()))
{
// Check the identity.
Debug.Write("\nAfter impersonation: "
+ WindowsIdentity.GetCurrent().Name);
AccessFolder(WindowsIdentity.GetCurrent(), #"E:\SDAVideo");
//Debug.Write("\nWriteAccess after: " + DirectoryHasPermission(#"E:\SDAVideo", WindowsIdentity.GetCurrent(), FileSystemRights.Write));
}
// Releasing the context object stops the impersonation
// Check the identity.
Debug.Write("\nAfter closing the context: " + WindowsIdentity.GetCurrent().Name);
}
}
catch (Exception ex)
{
Debug.Write("\n1" + ex.ToString());
}
public sealed class SafeTokenHandle : SafeHandleZeroOrMinusOneIsInvalid
{
private SafeTokenHandle()
: base(true)
{
}
[DllImport("kernel32.dll")]
[ReliabilityContract(Consistency.WillNotCorruptState, Cer.Success)]
[SuppressUnmanagedCodeSecurity]
[return: MarshalAs(UnmanagedType.Bool)]
private static extern bool CloseHandle(IntPtr handle);
protected override bool ReleaseHandle()
{
return CloseHandle(handle);
}
}
public static bool DirectoryHasPermission(string DirectoryPath, WindowsIdentity identity, FileSystemRights AccessRight)
{
//if (string.IsNullOrEmpty(DirectoryPath)) return false;
try
{
AuthorizationRuleCollection rules = Directory.GetAccessControl(DirectoryPath).GetAccessRules(true, true, typeof(System.Security.Principal.SecurityIdentifier));
//WindowsIdentity identity = WindowsIdentity.GetCurrent();
Debug.Write("\nUSER: " + identity.Name);
foreach (FileSystemAccessRule rule in rules)
{
if (identity.Groups.Contains(rule.IdentityReference))
{
if ((AccessRight & rule.FileSystemRights) == AccessRight)
{
if (rule.AccessControlType == AccessControlType.Allow)
return true;
}
}
}
}
catch (Exception ex)
{
Debug.Write("\n2 " + ex.ToString());
}
return false;
}
public static void AccessFolder(WindowsIdentity identity, string DirectoryPath)
{
try
{
Debug.Write("\nUSER: " + identity.Name);
DirectoryInfo myDirectoryInfo = new DirectoryInfo(DirectoryPath);
DirectorySecurity myDirectorySecurity = myDirectoryInfo.GetAccessControl();
myDirectorySecurity.AddAccessRule(new FileSystemAccessRule(identity.Name, FileSystemRights.Write, AccessControlType.Allow));
myDirectoryInfo.SetAccessControl(myDirectorySecurity);
string pathString = System.IO.Path.Combine(DirectoryPath, "test.txt");
if (!System.IO.File.Exists(pathString))
{
using (System.IO.FileStream fs = System.IO.File.Create(pathString))
{
for (byte i = 0; i < 100; i++)
{
fs.WriteByte(i);
}
}
}
}
catch (Exception ex)
{
Debug.Write("\n3 " + ex.ToString());
}
}
Error I get as follows
System.UnauthorizedAccessException: Attempted to perform an unauthorized operation.
System.InvalidOperationException: Method failed with unexpected error code 1346.
All of these failed, Only thing I am able to do is successfully get the Admin user windows identity.
Now with that I need to solve the two issues
1. How to check if app has write access using the windows identity of the admin
2. If so how to write something into the folder.

Try that:
using System;
using System.IO;
using System.Security.AccessControl;
namespace MyWpfApplication
{
public class AccessRules
{
private void SetAccessRuleForCurrentUser()
{
DirectoryInfo myDirectoryInfo = new DirectoryInfo(#"e:\Folder1");
DirectorySecurity myDirectorySecurity = myDirectoryInfo.GetAccessControl();
myDirectorySecurity.AddAccessRule(new FileSystemAccessRule(System.Security.Principal.WindowsIdentity.GetCurrent().Name, FileSystemRights.Read, AccessControlType.Allow));
myDirectoryInfo.SetAccessControl(myDirectorySecurity);
}
}
}

How to determine if a normal user is using elevated rights

I am trying to determinate if my program was launched by an Administrator with admin rights or by a normal user with Administrator rights using the following code:
private void Form1_Load(object sender, EventArgs e)
{
WindowsIdentity identity = WindowsIdentity.GetCurrent();
WindowsPrincipal principal = new WindowsPrincipal(identity);
bool isAdmin = principal.IsInRole(WindowsBuiltInRole.Administrator);
if (isAdmin)
{
ini();
MessageBox.Show("The user is an admin with admin rights");
}
else
{
MessageBox.Show("Error The user is a normal user with admin rights", MessageBoxButtons.OK, MessageBoxIcon.Exclamation);
Application.Exit();
}
}
But when I test this code using a normal user account with admin rights, it fails, telling me The user is an admin with admin rights.
I am using .Net 3.5 and the code needs to be compatible with Windows Vista and up.
Can anybody give me some idea to solve this, please? Thank you!!!
To clarify a little bit more, another way to see this problem is this: How can I determinate if my program (running with admin rights by the admin) is running inside the standard user account context.

mmm you need to know is if the user connected to that computer has Admin Rights but an user that is part of a domain control ? (active Directory?) not the BuiltIn ones ? please Clarify., take a look to this post https://social.msdn.microsoft.com/Forums/vstudio/en-US/c2166023-fcfc-4c3c-ba8f-200977971c5d/how-to-check-if-given-user-have-admin-rights-in-c

There are more variables to account for, for instance Operating System. Which version of Microsoft Window's are you utilizing? Remember, the User Access Control (UAC) was introduced in a later version, which can impact the code. Another massive impactor will be a Domain Policy which is regulated through Active Directory.
To avoid those constraints, I would do the following:
private static bool IsElevated()
{
var user = WindowsIdentity.GetCurrent();
var role = WindowsPrincipal(user);
if(Environment.OSVersion.Platform == PlatformID.Win32NT || Environment.OSVersion.Version.Major > 6)
if(user != null)
if(role.IsInRole(WindowsBuiltInRole.Administrator))
return true;
return false;
}
This was a quick recreation, but you'll want to test the code to ensure it correctly queries the Operating System and User.

I did solved it!!!
Explanation
I realized that what I needed was the session ID (the enviroment) to get somehow the Logged in Username
(owner of the context).
Getting the session Id was really easy:
int session = System.Diagnostics.Process.GetCurrentProcess().SessionId;
By this time, my goal was getting the username linked to this session, then I found this
Get Windows user name from SessionID
Now, with the username I thought it was really easy to check if this username belongs
to an Administrator group. I was wrong. The easiest way that I found requeried to use wmi and pinvoke.
The main problem was, in order to make the queries, I must know the name of the administrators group in the current OS, that is language-dependent.
The solution was this:
http://www.pinvoke.net/default.aspx/advapi32.lookupaccountsid
I tweaked the code, put all pieces together and that was it.
Summarizing, I found the sessionid, found the username linked to session, found the OS Administrators group name, and did some Wmi queries to check if the user is an Administrator.
This solution works fine for me, but I must say that runs slow.
If anybody can improve this code, or if it is useful to anybody else, I left it here.
Just remember to add a reference to System.Management; I used Visual Studio C# Express 2010. The project was a Windows Forms Application.
Happy coding!!!
//Make sure to add a reference to System.Management;
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Management;
using System.Security.Principal;
using System.Collections;
using System.Runtime.InteropServices;
namespace RealUSer
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void button1_Click(object sender, EventArgs e)
{
//Getting the session id
int session = System.Diagnostics.Process.GetCurrentProcess().SessionId;
//Getting the username related to the session id
string user = GetUsernameBySessionId(session, false);
try
{
//Cheching if the user belongs to the local admin group using wmi
if (CheckAdminRights(user))
{
MessageBox.Show("The logged in User "+user+" is an Admin");
}
else
{
MessageBox.Show("The logged in User " + user + " is not an Admin");
}
}
catch (Exception ex)
{
Console.WriteLine(ex.Message);
}
}
/// <summary>
/// This method checks if the context user, belongs to the local administrators group
/// </summary>
/// <param name="username"></param>
/// <returns></returns>
public bool CheckAdminRights(string username)
{
bool result = false;
List<string> admins = new List<string>();
//SelectQuery query = new SelectQuery("Select AccountType from Win32_UserAccount where Name=\"" + username + "\"");
SelectQuery query = new SelectQuery("SELECT * FROM win32_group WHERE Name=\"" + getAdministratorGroupName() + "\"");
ManagementObjectSearcher searcher = new ManagementObjectSearcher(query);
ManagementObjectCollection OC = searcher.Get();
IEnumerator enumerator = OC.GetEnumerator();
enumerator.MoveNext();
ManagementObject O = (ManagementObject)enumerator.Current;
ManagementObjectCollection adminusers = O.GetRelated("Win32_UserAccount");
foreach (ManagementObject envVar in adminusers)
{
admins.Add(envVar["Name"].ToString());
//Console.WriteLine("Username : {0}", envVar["Name"]);
//foreach (PropertyData pd in envVar.Properties)
// Console.WriteLine(string.Format(" {0,20}: {1}", pd.Name, pd.Value));
}
if (admins.Contains(username))
result = true;
return result;
}
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
///This code will find the administrators group name, independent of the OS language using the LookupAccountSid function with the BUILTIN\Administrators sid
#region
const int NO_ERROR = 0;
const int ERROR_INSUFFICIENT_BUFFER = 122;
enum SID_NAME_USE
{
SidTypeUser = 1,
SidTypeGroup,
SidTypeDomain,
SidTypeAlias,
SidTypeWellKnownGroup,
SidTypeDeletedAccount,
SidTypeInvalid,
SidTypeUnknown,
SidTypeComputer
}
[DllImport("advapi32.dll", CharSet = CharSet.Auto, SetLastError = true)]
static extern bool LookupAccountSid(
string lpSystemName,
[MarshalAs(UnmanagedType.LPArray)] byte[] Sid,
StringBuilder lpName,
ref uint cchName,
StringBuilder ReferencedDomainName,
ref uint cchReferencedDomainName,
out SID_NAME_USE peUse);
public string getAdministratorGroupName()
{
String result = "";
StringBuilder name = new StringBuilder();
uint cchName = (uint)name.Capacity;
StringBuilder referencedDomainName = new StringBuilder();
uint cchReferencedDomainName = (uint)referencedDomainName.Capacity;
SID_NAME_USE sidUse;
// Sid for BUILTIN\Administrators
byte[] Sid = new byte[] { 1, 2, 0, 0, 0, 0, 0, 5, 32, 0, 0, 0, 32, 2 };
int err = NO_ERROR;
if (!LookupAccountSid(null, Sid, name, ref cchName, referencedDomainName, ref cchReferencedDomainName, out sidUse))
{
err = System.Runtime.InteropServices.Marshal.GetLastWin32Error();
if (err == ERROR_INSUFFICIENT_BUFFER)
{
name.EnsureCapacity((int)cchName);
referencedDomainName.EnsureCapacity((int)cchReferencedDomainName);
err = NO_ERROR;
if (!LookupAccountSid(null, Sid, name, ref cchName, referencedDomainName, ref cchReferencedDomainName, out sidUse))
err = System.Runtime.InteropServices.Marshal.GetLastWin32Error();
}
}
if (err == 0)
{
result = name.ToString();
}
return result;
}
#endregion
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
private void Form1_Load(object sender, EventArgs e)
{
}
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
///This code will retrieve user name given the session id
#region
[DllImport("Wtsapi32.dll")]
private static extern bool WTSQuerySessionInformation(IntPtr hServer, int sessionId, WTS_INFO_CLASS wtsInfoClass, out System.IntPtr ppBuffer, out int pBytesReturned);
[DllImport("Wtsapi32.dll")]
private static extern void WTSFreeMemory(IntPtr pointer);
public static string GetUsernameBySessionId(int sessionId, bool prependDomain)
{
IntPtr buffer;
int strLen;
string username = "SYSTEM";
if (WTSQuerySessionInformation(IntPtr.Zero, sessionId, WTS_INFO_CLASS.WTSUserName, out buffer, out strLen) && strLen > 1)
{
username = Marshal.PtrToStringAnsi(buffer);
WTSFreeMemory(buffer);
if (prependDomain)
{
if (WTSQuerySessionInformation(IntPtr.Zero, sessionId, WTS_INFO_CLASS.WTSDomainName, out buffer, out strLen) && strLen > 1)
{
username = Marshal.PtrToStringAnsi(buffer) + "\\" + username;
WTSFreeMemory(buffer);
}
}
}
return username;
}
public enum WTS_INFO_CLASS
{
WTSInitialProgram,
WTSApplicationName,
WTSWorkingDirectory,
WTSOEMId,
WTSSessionId,
WTSUserName,
WTSWinStationName,
WTSDomainName,
WTSConnectState,
WTSClientBuildNumber,
WTSClientName,
WTSClientDirectory,
WTSClientProductId,
WTSClientHardwareId,
WTSClientAddress,
WTSClientDisplay,
WTSClientProtocolType
}
#endregion
}
}

How to get current windows username from windows service in multiuser environment using .NET

I have a windows service which run a WPF application all the time for all the logged in users which works fine, now in the WPF application i can not get a current username as Environment.UserName; returns 'SYSTEM' which is understandable. so what i thought was to find session id of current process which could be retrieved by Process.GetCurrentProcess().SessionId and then get the list of all users logged in to the machine and looping through it to find the session id match with process session id and later his username.
but i don't how to get the list of all logged in users or i would appreciate if someone can help me with alternative.

I ran into a similar problem while building a Windows Service. Just like you, I had the Session ID and needed to get the corresponding username. Syed's answer above did not work on my machine (Windows 10) as Microsoft seems to have removed the quser executable. After several unsuccessful solution hereon SO, I ran into this particular answer and it inspired my solution:
Here's my code (all of them residing inside a class; in my case, the class inheriting ServiceBase)
[DllImport("Wtsapi32.dll")]
private static extern bool WTSQuerySessionInformation(IntPtr hServer, int sessionId, WtsInfoClass wtsInfoClass, out IntPtr ppBuffer, out int pBytesReturned);
[DllImport("Wtsapi32.dll")]
private static extern void WTSFreeMemory(IntPtr pointer);
private enum WtsInfoClass
{
WTSUserName = 5,
WTSDomainName = 7,
}
private static string GetUsername(int sessionId, bool prependDomain = true)
{
IntPtr buffer;
int strLen;
string username = "SYSTEM";
if (WTSQuerySessionInformation(IntPtr.Zero, sessionId, WtsInfoClass.WTSUserName, out buffer, out strLen) && strLen > 1)
{
username = Marshal.PtrToStringAnsi(buffer);
WTSFreeMemory(buffer);
if (prependDomain)
{
if (WTSQuerySessionInformation(IntPtr.Zero, sessionId, WtsInfoClass.WTSDomainName, out buffer, out strLen) && strLen > 1)
{
username = Marshal.PtrToStringAnsi(buffer) + "\\" + username;
WTSFreeMemory(buffer);
}
}
}
return username;
}

I solve it by executing powershell command "quser" in my WPF application which returns all the logged in users then I am iterating to find session id in which the application is running with user session id and then retrieving his name. below is the function which fetch the username by passing his session id
private string GetUserName(int SessionId)
{
try
{
Runspace runspace = RunspaceFactory.CreateRunspace();
runspace.Open();
Pipeline pipeline = runspace.CreatePipeline();
pipeline.Commands.AddScript("Quser");
pipeline.Commands.Add("Out-String");
Collection<PSObject> results = pipeline.Invoke();
runspace.Close();
StringBuilder stringBuilder = new StringBuilder();
foreach (PSObject obj in results)
{
stringBuilder.AppendLine(obj.ToString());
}
foreach (string User in stringBuilder.ToString().Split(new string[] { Environment.NewLine }, StringSplitOptions.RemoveEmptyEntries).Skip(1))
{
string[] UserAttributes = User.Split(new string[]{" "},StringSplitOptions.RemoveEmptyEntries);
if (int.Parse(UserAttributes[2].Trim()) == SessionId)
{
return UserAttributes[0].Replace(">", string.Empty).Trim();
}
}
return stringBuilder.ToString();
}
catch (Exception ex)
{
}
return string.Empty;
}
the function can be called by
string CurrentUser = GetUserName(Process.GetCurrentProcess().SessionId);

You can try this Code spinet.
Whenever a user logged onto windows, the Username attribute will contain the username of the user. In the case when there are no users in the windows system, there will be no instances of the Win32_ComputerSystem class.
ManagementScope ms = new ManagementScope("\\\\.\\root\\cimv2");
ObjectQuery query = new ObjectQuery("SELECT * FROM Win32_ComputerSystem");
ManagementObjectSearcher searcher = new ManagementObjectSearcher(ms, query);
foreach(ManagementObject mo in searcher.Get())
{
Console.WriteLine(mo["UserName"].ToString());
}

Found this solution on MSDN forums:
using System.Security.Principal;
.
.
.
WindowsPrincipal wp = new WindowsPrincipal(WindowsIdentity.GetCurrent());
String username = wp.Identity.Name;
Now this is easily tested by creating a new Console Application, pasting the above code, and writing the username string to Console. Seems to work fine, but for services it's apparently a more complex situation. Since all services are run in a container that runs under the SYSTEM user, that's what they return. For more information see the below link, esp. all Harry Zhu's answers.
http://social.msdn.microsoft.com/Forums/vstudio/en-US/3be119b0-88b4-442e-9613-6856cbb27adb/how-can-i-get-current-username-in-windows-service?forum=csharpgeneral
It would seem it's not possible to achieve what you are trying to get, as services are totally seperate from users' session.

i made a little search and find this code that should work for you:
it will get the username whom is running the process...
reference: How do I determine the owner of a process in C#?
public string GetProcessOwner(string processName)
{
string query = "Select * from Win32_Process Where Name = \"" + processName + "\"";
ManagementObjectSearcher searcher = new ManagementObjectSearcher(query);
ManagementObjectCollection processList = searcher.Get();
foreach (ManagementObject obj in processList)
{
string[] argList = new string[] { string.Empty, string.Empty };
int returnVal = Convert.ToInt32(obj.InvokeMethod("GetOwner", argList));
if (returnVal == 0)
{
// return DOMAIN\user
string owner = argList[1] + "\\" + argList[0];
return owner;
}
}
return "NO OWNER";
}

You can try this Code:
string username = "SYSTEM";
var explorer = Process.GetProcessesByName("explorer").FirstOrDefault();
if (explorer != null)
{
username = GetUsername(explorer.SessionId);
}
Implementation of method GetUsername here: https://stackoverflow.com/a/35810391/10412686