I am searching for a way to close a process running under any user by a windows service running under the system account. I've nearly tried everything but I could not find any solution except killing the process.
Why can't I kill the process?
I can't kill the process uses a tray icon. If I kill the process, the tray icon won't disappear.
What I've tried so far
I've already tried to use global eventhandles (did not work because the child process got extremely laggy).
I also tried to use PostMessage/SendMessage to communicate with the process. That solution did not work because a windows service can not interact with any user interfaces,...
I found another question (here on stackoverflow) which describes exactly my problem: Close a child process from a windows service.
This question does not contain a nice solution.
First of all I don't use C++ instead of C#. The next problem is, that the child process uses a mouse hook. So it has so run very fast without many overhead. Otherwise it would get laggy which would mean, that the mouse would lag on the whole system.
So is there really no simple solution to close a process from a windows service?
A service can use SetProcessWindowStation() and SetThreadDesktop() to attach to the interactive desktop of the target process before then sending messages to the target process.
Alternatively, the service can use CreateProcessAsUser() to run a new process in the same session as the target process, and then that process can send messages to the target process.
Related
Is there some way to launch a process in non-elevated way from an elevated one. My setup is launched elevated and when it finalizes, it will just launch the main application. Because the setup is elevated, the main process will be elevated as well which is not desirable. What is the best solution to this?
That's a problem, Vista/Win7 don't appear to have an API to obtain the unprivileged user token you need to call CreateProcessAsUser(). The only solutions I've found involve using the task scheduler to launch the program. That doesn't strike me as very practical.
An easy solution that jumps to mind is to use a small non-elevated helper process. It can in turn launch the elevated setup process and wait for a confirmation from that one to launch the non-elevated one. The handshake is simple enough to do this with a named mutex.
The only way to do this without hacks is to have two processes (Can be implemented in the same .exe)
Instance A starts Instance B with ShellExecute and the runas verb.
B does the installing, when its time to start your app on the "finish page", it uses some form of inter processes communication (RPC, shared memory+events etc) with A telling it to start a process on its behalf.
This seems like a nice way to do it, provided you don't care about situations where the Shell is not running (e.g. possibly some Terminal Services application-only setups, perhaps, though I'm not sure):
http://brandonlive.com/2008/04/27/getting-the-shell-to-run-an-application-for-you-part-2-how/
It gets an interface to Explorer.exe, which should be running in the user's normal context, and asks Explorer to execute a command in its behalf. This is done just using simple, documented COM interfaces and without having to mess around with process tokens or code/DLL injection.
We have a native GUI application which runs on a windows machine, and recently we have found out that the application terminates unexpectedly. After days I have found that this is happening because the application is run by explorer.exe and it gets killed unexpectedly, random somehow, so it causes termination of all child processes including our application.
Is there a way to invoke/call our app as system process (not with explorer.exe)?
Also assume that application/user has administrator access too.
Thanks in advance.
Killing explorer does not in general kill other processes. This is very easy to verify yourself by killing explorer from the task manager. Notice that other processes stay alive when you kill explorer. Something else is killing your process.
If killing explorer leads to your process dying, then the obvious explanation is that something in your process is leading to its death. In other words the problem is most likely in your code, and you need to work out what that problem is.
Also note that explorer isn't really a special "system process" as such. It's just a normal process that that runs under the logged on user's token.
You may need to give some hand of a OS services, then run the service as admin(run as system boot), then start he application from the service ,this will ensures you the app will started as admin and without the explorer.exe(as child)
How Can I execute a function when Windows shutdown. Here is my scenario, I am mounting a drive using WNetAddConnection2 function in my application. Now I want user to set the option if the drive will be mounted on next system startup or not.
If he selects , not to mount on next startup , then I need to remove the drive using WNetCancelConnection2 , but this should only happen when user shutdown the system.
I can only think of only solution. Create a service which will check the user option and then decide whether to mount the drive or not.
Are there any other ways to go ahead with it?
If you have a main window (even an invisible one) that can process messages, you can handle the WM_ENDSESSION message.
See: http://msdn.microsoft.com/en-us/library/aa376889(v=VS.85).aspx
If you can make your app into a Windows service (or have your app communicate state with one that you provide) you can perform required actions on receipt of SERVICE_CONTROL_SHUTDOWN in your service control handler function. This would decouple your app that handles user interaction from the shutdown handling, which requires something to be running all the time (what if the user logs off?).
explorer.exe is the GUI process of windows which usually only gets shut down if Windows shuts down (exceptions have to be made for certain error conditions). You could listen on the WM_DESTROY window message for the process ID of explorer.exe and dismount then.
The way I can think of is to:
Register your program to auto Start up (when PC starts). Here's a tutorial on howto.
Store the user option (as mentioned above) in a repository or registry (if you know how). When your app would have started, you can read your registry and act accordingly.
For shutdown, your application will have to hook itself on a SystemEvent to detect shutdown (then you can act accordingly). Here's an example on howto (C#). For C++, you can listen to WM_ENDSESSION message.
I hope that my 2 cents can help you.
I have a C++ Win32 application that was written as a Windows GUI project, and now I'm trying to figure out to make it into a Service / GUI hybrid. I understand that a Windows Service cannot / should not have a user interface. But allow me to explain what I have so far and what I'm shooting for.
WHAT I HAVE NOW is a windows application. When it is run it places an icon in the system tray that you can double-click on to open up the GUI. The purpose of this application is to process files located in a specified directory on a nightly schedule. The GUI consists of the following:
A button to start an unscheduled scan/process manually.
A button to open a dialog for modifying settings.
A List Box for displaying status messages sent from the processing thread.
A custom drawn window for displaying image data (the file processing includes the creation and saving of images).
A status bar - while a process is not running, it shows a countdown to the next scheduled scan. During a scan it also provides some status feedback, including a progress bar.
WHAT I'M SHOOTING FOR is a service that will run on boot-up and not require a user to login. This would consist of the scheduled file processing. However, when a user logs in I would still like the tray icon to be loaded and allow them to open up a GUI as I described above to monitor the current state of the service, change settings, start a scan manually, and monitor the progress of a scan.
I'm sure that I have seen applications like this - that function as a service even when I'm not logged in, but still give me a user interface to work with once I do log in.
I'm thinking that instead of having a single multi-threaded application that sends messages to the GUI thread from the processing thread, I need two applications - a Service to perform the processing and a GUI application to provide visual feedback from the Service and also send messages to the Service (for example, to start a scan manually). But I am new to Windows Services and have no idea how this is done.
It is also possible that I'm completely off base and a Service is not what I'm looking for at all.
Any help / ideas / suggestions would be greatly appreciated! Thank you.
You can't do this as a service.
You'll need to make your Windows Service as a normal service application. This will startup on system startup, and run the entire time the system is up.
You'd then make a completely separate GUI application, which "talks" to the service. This can be set to run when a user logs in, in the user's account.
In order to make them "talk" to each other, you'll need to use some form of IPC. Since these run on the same system (but in different accounts, typically), named pipes or sockets both work quite well.
There is a simple way of doing it.
You can’t have the service access any user’s session (session 1,2,3..) since services are isolated and can access session 0 only. This is a change from 2011.
You should write a win32 program to be launched by your service per each user who logs in using https://msdn.microsoft.com/en-us/library/windows/desktop/ms682429(v=vs.85).aspx
The service can continue performing any task that isn’t user specific.
I have a single thread that I'd like to run as an administrator in my application. The rest of the application I can happily run as the default user level (asInvoker). Is this possible? I notice there is an "ImpersonateLoggedOnUser" function. Can I somehow use this to log the administrator on and then get the thread to impersonate that person?
It seems as though this ought to be something pretty trivial to do ... but there doesn't appear to be any obvious way to do it. Can anyone help me out?
Edit: So if I have to fire off a seperate process is there any way I can CreateProcess a new process and have it launch from a specific entry point. I can, of course use command line processing to do it, but i'd really rather I could stop the user from entering the command line and starting an unclosable process!
No, elevation is per process, not thread.
If the rest of the application has to run non-elevated, you could run yourself elevated with some parameter (myapp.exe /uac "ipcparamhere") and use some sort of Inter-process communication to communicate back to the "main instance" of your app. (If the elevated process only performs a simple operation, you could probably check for success by using the exit code of the process)
This is not possible. You'll need to gain admin privileges by including a manifest in the app. Google "requireAdministrator" to find the manifest you'll need. Your user will probably quickly tire of doing this over and over again, your best bet is to spin-off the task that requires these privileges into a separate process. A service for example.
You can launch a separate exe and have a manifest on it saying it requires administrator. Then be sure to launch it with shell execute, which uses manifests, and you're all set. As a thoughtful touch, put a UAC shield on the button that kicks off that thread. (Send it a BCM_SETSHIELD message if you're doing this all by hand.)
You can decided whether you want a visible window or not on the separate process. Meanwhile the user can still drag and drop into the main app.