Is it possible to require administrator rights for one single method?
Something like this:
[RequireAdminRightsForThisMethod()]
private void TheMethod(){
// Do something
}
You can add a PrincipalPermission attribute to your method to demand administrative privileges for its execution:
[PrincipalPermission(SecurityAction.Demand, Role = #"BUILTIN\Administrators")]
public void MyMethod()
{
}
This is described in more detail in the following article:
Security Principles and Local Admin Rights in C# .Net
If you are looking for a way to elevate an already existing process I doubt that this is possible as administrator privileges are given on process-level to a process upon startup (see this related question). You would have to run your application "as administrator" to get the desired behavior.
However, there are some tricks that might allow you to do what you want, but be warned that this might open up severe security risks. See the following thread in the MSDN forums:
Launching MyElevatedCom Server without prompting Administrator credentialls from Standard User
Update (from comment)
It seems that if an update requires elevation your application update is best done by a separate process (either another executable, or your application called with a command line switch). For that separate process you can request elevation as follows:
var psi = new ProcessStartInfo();
psi.FileName = "path to update.exe";
psi.Arguments = "arguments for update.exe";
psi.Verb = "runas";
var process = new Process();
process.StartInfo = psi;
process.Start();
process.WaitForExit();
A method can require administrative privileges to run, but it's not possible to automatically elevate to Admin when executing a method.
Related
i searched for this some hours today but i only find solutions that wont work.
Maybe it is impossible but let's give it a try:
I'm in a company and I will write some code so that a user can run the software whenever he need it. The software needs administrator-permissions. For example I've wrote some code to start the cmd as admin and create a folder at c:/Windows (you'll need admin-permission for that). The credentials for the admin account are right (we use Microsoft AD) but I only get "Access denied" in the cmd.
Does anyone know whether it is possible to get admin permission with hard coded credentials?
Note: Don't talk about security risks, the cmd is not the target software but it should demonstrate the problem.
My code:
Process p = new Process();
p.StartInfo.FileName = "cmd.exe";
p.StartInfo.Arguments = #"/Kmkdir C:\Windows\_Test";
p.StartInfo.UserName = "admin";
System.Security.SecureString sPW = new System.Security.SecureString();
sPW.AppendChar('a');
sPW.AppendChar('b');
sPW.AppendChar('c');
p.StartInfo.Password = sPW;
p.StartInfo.UseShellExecute = false;
p.Start();
You are still getting an error because all admin accounts in newer windows versions (since Vista) technically are standard user accounts. The way administrative tasks are performed is through the User Account Control (UAC). It allows you to elevate permissions as administrator to perform administrative tasks. So yes, you are executing the process using an administrator account, but you did not elevate the process. To do so, add this parameter:
p.StartInfo.Verb = "runas";
p.StartInfo.UseShellExecute = true;
You can remove all other parameters regarding authentication, since all the authentication is handled by UAC. If for some reason you wish not to use UAC, then you probably will have to disable it, which is not recommended in most cases.
I wrote an application, that grab time from NTP server and change system time of my machine. It works good, but time synchronizing only if my apps start with admin rights. So a question is how to launch it without admin privileges, but to save it functionality?
I set system time using WinAPI function SetSystemTime.
you can do this in several ways (have the most proper one for you).
Identity Impersonation => described with example at this address
WindowsIdentity identity = new WindowsIdentity(accessToken);
WindowsImpersonationContext context = identity.Impersonate() ;
runas verb
ProcessStartInfo startInfo = new ProcessStartInfo (m_strInstallUtil, strExePath);
startInfo.Verb = "runas";
System.Diagnostics.Process.Start (startInfo);
please keep in mind that UAC will be prompted for the second method
PrincipalPermissin (if the user is the member of Admin group)
[PrincipalPermission(SecurityAction.Demand, Role = #"BUILTIN\Administrators")]
I am running an executable process from my ASP.NET application when a user clicks a button. This process creates several files and serves them up to the end-user. I can't really see what the process is or isn't doing, but it didn't work until I specified the admin user as the application pool identity on the server. I am using IIS7.
using (var proc = new Process())
{
proc.StartInfo.FileName = Server.MapPath("~/Testing/Demo/MyExe.exe");
proc.StartInfo.Arguments = String.Format("\"{0}\"", commandFilePath);
proc.StartInfo.UseShellExecute = true;
proc.Start();
proc.WaitForExit();
}
I'm assuming that this is generally a bad thing to do. Can you give me insight into what needs to be done in order to enable this for the normal ApplicationPoolIdentity account?
Thanks!
First of all, why you need the Shell to execute it ? Isn't a console application - do you open any window ?
Second you need to redirect the input and the output.
And final, what you need to do, is to place on the directory that your script runs, permission for the user under witch your pool is run. And remove the Admin from your pool.
proc.StartInfo.UseShellExecute = false;
proc.StartInfo.CreateNoWindow = false;
proc.StartInfo.RedirectStandardError = true;
proc.StartInfo.RedirectStandardOutput = true;
proc.StartInfo.RedirectStandardInput = true;
proc.Start();
proc.StandardInput.Flush();
proc.StandardInput.Close();
proc.WaitForExit();
proc.Close();
So for example, if you add your pool to run under the UserA, then go to your directory that your program runs and add permission for the UserA to been able to execute programs on that directory. If your program also use other directories to read and write, also add permission to the UserA for that ones.
I can't really see what the process is or isn't doing
You can take a look if you use on the server the Process Explorer and see if its runs, if its close, if its stop but stay there.
It is likely a file/execution permissions issue.
Try granting execute permissions to the ApplicationPoolIdentity to ~/Testing/Dema/MyExe.exe and read permissions to commandFilePath. You mentioned that your process creates files. You will need to grant either modify or full control permissions to the ApplicationPoolIdentity on the folder where the files will be created. Here is a matrixed list of permissions.
See assign permissions to ApplicationPoolIdentity account for information on granting permissions.
The security event log should capture permission denied errors. Check there to see if you have access permission issues. The System and application logs might also contain information on the problem.
Process Explorer can also show File Access requests. Here is a technet article on troubleshooting with Process Explorer.
Whenever you run any process from an ASP.NET page, it runs under the security context of the worker process, the privilege of your app pool account. It is not like you normally running the MyExe.exe, in that case it will run using logged in account. It is because of this, your code worked when you gave Admin account to app pool.
There are many ways to solve this issue.
One of the easiest would be to change your app pool identity to Network Service and add the Network Service to permissions of the folders in which the MyExe.exe will be accessing files form.
Hope it helps.
Thank you all for your help. All I needed to do was set the StartInfo.WorkingDirectory to somewhere that I was able to write.
using (var proc = new Process())
{
proc.StartInfo.FileName = Server.MapPath("~/Testing/Demo/MyEXE.exe");
proc.StartInfo.Arguments = String.Format("\"{0}\"", commandFile);
proc.StartInfo.WorkingDirectory = savePath;
proc.Start();
proc.WaitForExit();
}
This causes the temp files to be written to a non-system folder and thus does not need any elevated permissions for the application pool.
In my application, if the user saves a file to a folder they don't have permissions for, File.Copy will fail. An example is saving a document to the C:\ root.
Instead of denying access, I'd like to prompt the user to elevate permissions with a UAC prompt, but only for this save function (not for the entire application). Is there a way to do this?
In short... no.
The entire process needs to be elevated and that elevation needs to happen at startup. However! You can create a separate process to do this work. Make a separate .exe that does only this work and gets everything it needs in the command line parameters. You can add verbs to the process that will cause it to be elevated:
Process p = new Process();
p.StartInfo.FileName = "copy.exe";
p.StartInfo.Arguments = new [] { pathFrom, pathTo };
p.Verb = "runas";
p.Start();
Something like that...
I'm trying to install a service using InstallUtil.exe but invoked through Process.Start. Here's the code:
ProcessStartInfo startInfo = new ProcessStartInfo (m_strInstallUtil, strExePath);
System.Diagnostics.Process.Start (startInfo);
where m_strInstallUtil is the fully qualified path and exe to "InstallUtil.exe" and strExePath is the fully qualified path/name to my service.
Running the command line syntax from an elevated command prompt works; running from my app (using the above code) does not. I assume I'm dealing with some process elevation issue, so how would I run my process in an elevated state? Do I need to look at ShellExecute for this?
This is all on Windows Vista. I am running the process in the VS2008 debugger elevated to admin privilege.
I also tried setting startInfo.Verb = "runas"; but it didn't seem to solve the problem.
You can indicate the new process should be started with elevated permissions by setting the Verb property of your startInfo object to 'runas', as follows:
startInfo.Verb = "runas";
This will cause Windows to behave as if the process has been started from Explorer with the "Run as Administrator" menu command.
This does mean the UAC prompt will come up and will need to be acknowledged by the user: if this is undesirable (for example because it would happen in the middle of a lengthy process), you'll need to run your entire host process with elevated permissions by Create and Embed an Application Manifest (UAC) to require the 'highestAvailable' execution level: this will cause the UAC prompt to appear as soon as your app is started, and cause all child processes to run with elevated permissions without additional prompting.
Edit: I see you just edited your question to state that "runas" didn't work for you. That's really strange, as it should (and does for me in several production apps). Requiring the parent process to run with elevated rights by embedding the manifest should definitely work, though.
This code puts the above all together and restarts the current wpf app with admin privs:
if (IsAdministrator() == false)
{
// Restart program and run as admin
var exeName = System.Diagnostics.Process.GetCurrentProcess().MainModule.FileName;
ProcessStartInfo startInfo = new ProcessStartInfo(exeName);
startInfo.Verb = "runas";
System.Diagnostics.Process.Start(startInfo);
Application.Current.Shutdown();
return;
}
private static bool IsAdministrator()
{
WindowsIdentity identity = WindowsIdentity.GetCurrent();
WindowsPrincipal principal = new WindowsPrincipal(identity);
return principal.IsInRole(WindowsBuiltInRole.Administrator);
}
// To run as admin, alter exe manifest file after building.
// Or create shortcut with "as admin" checked.
// Or ShellExecute(C# Process.Start) can elevate - use verb "runas".
// Or an elevate vbs script can launch programs as admin.
// (does not work: "runas /user:admin" from cmd-line prompts for admin pass)
Update: The app manifest way is preferred:
Right click project in visual studio, add, new application manifest file, change the file so you have requireAdministrator set as shown in the above.
A problem with the original way: If you put the restart code in app.xaml.cs OnStartup, it still may start the main window briefly even though Shutdown was called. My main window blew up if app.xaml.cs init was not run and in certain race conditions it would do this.
According to the article Chris Corio: Teach Your Apps To Play Nicely With Windows Vista User Account Control, MSDN Magazine, Jan. 2007, only ShellExecute checks the embedded manifest and prompts the user for elevation if needed, while CreateProcess and other APIs don't. Hope it helps.
See also: same article as .chm.
[PrincipalPermission(SecurityAction.Demand, Role = #"BUILTIN\Administrators")]
This will do it without UAC - no need to start a new process. If the running user is member of Admin group as for my case.
i know this is a very old post, but i just wanted to share my solution:
System.Diagnostics.ProcessStartInfo StartInfo = new System.Diagnostics.ProcessStartInfo
{
UseShellExecute = true, //<- for elevation
Verb = "runas", //<- for elevation
WorkingDirectory = Environment.CurrentDirectory,
FileName = "EDHM_UI_Patcher.exe",
Arguments = #"\D -FF"
};
System.Diagnostics.Process p = System.Diagnostics.Process.Start(StartInfo);
NOTE: If VisualStudio is already running Elevated then the UAC dialog won't show up, to test it run the exe from the bin folder.
You should use Impersonation to elevate the state.
WindowsIdentity identity = new WindowsIdentity(accessToken);
WindowsImpersonationContext context = identity.Impersonate();
Don't forget to undo the impersonated context when you are done.