App does not Run as a service in a Windows Container

[Silvenga]

Description

Using the library Microsoft.Extensions.Hosting.WindowsServices and a builder like the following:

public static IHostBuilder CreateHostBuilder(string[] args)
{
    return Host.CreateDefaultBuilder(args)
        .UseWindowsService(options => options.ServiceName = "foobar")
        .ConfigureServices((hostContext, services) =>
        {
            services.AddHostedService<Agent>();
        });
}

When executing as a service in a Windows Container the following can be observed:

System event logs:

# Get-EventLog -LogName Application -Newest 10 | %{ $_.Message }
A timeout was reached (30000 milliseconds) while waiting for the foobar...
A timeout was reached (30000 milliseconds) while waiting for the foobar...
A timeout was reached (30000 milliseconds) while waiting for the foobar...

Application event logs:

# Get-EventLog -LogName Application -Newest 10 | %{ $_.Message }
Windows Management Instrumentation Service subsystems initialized successfully
Category: Microsoft.Extensions.Hosting.Internal.Host
EventId: 2

Hosting started

Category: Microsoft.Hosting.Lifetime
EventId: 0

Content root path: C:\Windows\system32

Category: Microsoft.Hosting.Lifetime
EventId: 0

Hosting environment: Production

Category: Microsoft.Hosting.Lifetime
EventId: 0

Application started. Press Ctrl+C to shut down.

Category: Microsoft.Extensions.Hosting.Internal.Host
EventId: 1

Hosting starting

Category: Microsoft.Extensions.Hosting.Internal.Host
EventId: 2

Hosting started

Category: Microsoft.Hosting.Lifetime
EventId: 0

Content root path: C:\Windows\system32

Category: Microsoft.Hosting.Lifetime
EventId: 0

Hosting environment: Production

Category: Microsoft.Hosting.Lifetime
EventId: 0

Application started. Press Ctrl+C to shut down.

It appears the the "host" (that the right name?) does not detect it's running as a service. So the app defaults to running as a console app.

Digging deeper, there's a check for "am I a service?" in Microsoft.Extensions.Hosting.WindowsServices.IsWindowsService().

runtime/src/libraries/Microsoft.Extensions.Hosting.WindowsServices/src/WindowsServiceHelpers.cs

Lines 18 to 31 in 01b7e73

	public static bool IsWindowsService()
	{
	if (!RuntimeInformation.IsOSPlatform(OSPlatform.Windows))
	{
	return false;
	}
	var parent = Internal.Win32.GetParentProcess();
	if (parent == null)
	{
	return false;
	}
	return parent.SessionId == 0 && string.Equals("services", parent.ProcessName, StringComparison.OrdinalIgnoreCase);
	}

Looking at what this checks:

• Is Windows? Yes.
• Is there a parent process? Yes.
• Is this process named services? Yes.
• Is this process executing from session 0? No?!?

# pslist.exe -accepteula -t

Name                             Pid Pri Thd  Hnd      VM      WS    Priv
Idle                               0   0   2    0       8       8      60
  System                           4   8  88 3565    3696     144     160
wininit                          276  13   3  167 4194303    7276    1640
  services                       316   9   5  225 4194303    6832    2348
    foobar                       2908   8  10  241 4194303   25380   12688

# Get-Process -id 316 | select name,SessionId

Name     SessionId
----     ---------
services         1

Apparently services doesn't have to run under session 0?

Other information

While "why are running an app in a Windows Container as a Windows Service? Don't do that." would be a completely valid answer.... We are using Windows Containers to provide short lived sandboxes for integration tests - in this case - testing a Wix installer, installing a .NET 5 based Windows Service (self-contained mode). It would be nice if we could continue doing so with .NET 5.

We were historically using TopShelf under .NET Framework, but we migrated to .NET 5. TopShelf does not perform this session 0 check, only the services name check: https://github.com/Topshelf/Topshelf/blob/03bde8963da8c057ffc6df07ef9600ffdf6047c1/src/Topshelf/Runtime/DotNetCore/DotNetCoreHostEnvironment.cs#L57-L80

Therefore, I propose removing that session id check going forward.

Tagging subscribers to this area: @eerhardt, @maryamariyan
See info in area-owners.md if you want to be subscribed.

Issue Details

---

Description

Using the library Microsoft.Extensions.Hosting.WindowsServices and a builder like the following:

public static IHostBuilder CreateHostBuilder(string[] args)
{
    return Host.CreateDefaultBuilder(args)
        .UseWindowsService(options => options.ServiceName = "foobar")
        .ConfigureServices((hostContext, services) =>
        {
            services.AddHostedService<Agent>();
        });
}

When executing as a service in a Windows Container the following can be observed:

System event logs:

# Get-EventLog -LogName Application -Newest 10 | %{ $_.Message }
A timeout was reached (30000 milliseconds) while waiting for the foobar...
A timeout was reached (30000 milliseconds) while waiting for the foobar...
A timeout was reached (30000 milliseconds) while waiting for the foobar...

Application event logs:

# Get-EventLog -LogName Application -Newest 10 | %{ $_.Message }
Windows Management Instrumentation Service subsystems initialized successfully
Category: Microsoft.Extensions.Hosting.Internal.Host
EventId: 2

Hosting started

Category: Microsoft.Hosting.Lifetime
EventId: 0

Content root path: C:\Windows\system32

Category: Microsoft.Hosting.Lifetime
EventId: 0

Hosting environment: Production

Category: Microsoft.Hosting.Lifetime
EventId: 0

Application started. Press Ctrl+C to shut down.

Category: Microsoft.Extensions.Hosting.Internal.Host
EventId: 1

Hosting starting

Category: Microsoft.Extensions.Hosting.Internal.Host
EventId: 2

Hosting started

Category: Microsoft.Hosting.Lifetime
EventId: 0

Content root path: C:\Windows\system32

Category: Microsoft.Hosting.Lifetime
EventId: 0

Hosting environment: Production

Category: Microsoft.Hosting.Lifetime
EventId: 0

Application started. Press Ctrl+C to shut down.

It appears the the "host" (that the right name?) does not detect it's running as a service. So the app defaults to running as a console app.

Digging deeper, there's a check for "am I a service?" in Microsoft.Extensions.Hosting.WindowsServices.IsWindowsService().

runtime/src/libraries/Microsoft.Extensions.Hosting.WindowsServices/src/WindowsServiceHelpers.cs

Lines 18 to 31 in 01b7e73

	public static bool IsWindowsService()
	{
	if (!RuntimeInformation.IsOSPlatform(OSPlatform.Windows))
	{
	return false;
	}
	var parent = Internal.Win32.GetParentProcess();
	if (parent == null)
	{
	return false;
	}
	return parent.SessionId == 0 && string.Equals("services", parent.ProcessName, StringComparison.OrdinalIgnoreCase);
	}

Looking at what this checks:

• Is Windows? Yes.
• Is there a parent process? Yes.
• Is this process named services? Yes.
• Is this process executing from session 0? No?!?

# pslist.exe -accepteula -t

Name                             Pid Pri Thd  Hnd      VM      WS    Priv
Idle                               0   0   2    0       8       8      60
  System                           4   8  88 3565    3696     144     160
wininit                          276  13   3  167 4194303    7276    1640
  services                       316   9   5  225 4194303    6832    2348
    foobar                       2908   8  10  241 4194303   25380   12688

# Get-Process -id 316 | select name,SessionId

Name     SessionId
----     ---------
services         1

Apparently services doesn't have to run under session 0?

Other information

While "why are running an app in a Windows Container as a Windows Service? Don't do that." would be a completely valid answer.... We are using Windows Containers to provide short lived sandboxes for integration tests - in this case - testing a Wix installer, installing a .NET 5 based Windows Service (self-contained mode). It would be nice if we could continue doing so with .NET 5.

We were historically using TopShelf under .NET Framework, but we migrated to .NET 5. TopShelf does not perform this session 0 check, only the services name check: https://github.com/Topshelf/Topshelf/blob/03bde8963da8c057ffc6df07ef9600ffdf6047c1/src/Topshelf/Runtime/DotNetCore/DotNetCoreHostEnvironment.cs#L57-L80

Therefore, I propose removing that session id check going forward.

Author:	Silvenga
Assignees:	-
Labels:	area-Extensions-Hosting, untriaged
Milestone:	-

[Silvenga]

If this proposal is acceptable, I would be happy to make a pr. 😸

[eerhardt]

Getting help from @GrabYourPitchforks offline, the following approach was recommended for identifying if the current process is hosted as a windows service:

1. enumerate the list of running services on the machine;
2. call QueryServiceStatusEx on each service handle; and
3. compare the service's PID to the current process's PID.

We can accomplish (1) above with calling:

runtime/src/libraries/System.ServiceProcess.ServiceController/src/System/ServiceProcess/ServiceController.cs

Lines 694 to 701 in 14d6532

	/// <summary>
	/// Gets the services (not including device-driver services) on the local machine.
	/// </summary>
	/// <returns>Set of service controllers</returns>
	public static ServiceController[] GetServices()
	{
	return GetServices(DefaultMachineName);
	}

Then p/invoke into QueryServiceStatusEx to get the service's PID. Comparing the current PID is straight-forward from there.

Moving to 7.0 and marking as "up for grabs".

[Silvenga]

Sounds good! I'll see if I have time to work this in the near future.

[Silvenga]

I'm not going to be able to work this any time soon. Needing to install native build sdk's/python, modifying PATH, etc. is a bit heavy for my current setup.

I don't suppose there's a way to work extensions without needing to build the whole runtime?