Mutex.GetAccessControl 메서드
정의
중요
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명명된 MutexSecurity 뮤텍스의 액세스 제어 보안을 나타내는 개체를 가져옵니다.
public:
System::Security::AccessControl::MutexSecurity ^ GetAccessControl();
public System.Security.AccessControl.MutexSecurity GetAccessControl();
member this.GetAccessControl : unit -> System.Security.AccessControl.MutexSecurity
Public Function GetAccessControl () As MutexSecurity
반품
MutexSecurity 명명된 뮤텍스의 액세스 제어 보안을 나타내는 개체입니다.
예외
현재 Mutex 개체는 명명된 시스템 뮤텍스를 나타내지만 사용자에게는 ReadPermissions없습니다.
-또는-
현재 Mutex 개체는 명명된 시스템 뮤텍스를 나타내며 ReadPermissions.
예제
다음 코드 예제에서는 액세스 제어 보안을 사용하여 명명된 뮤텍스의 교차 프로세스 동작을 보여 줍니다. 이 예제에서는 메서드 오버로드를 사용하여 OpenExisting(String) 명명된 뮤텍스가 있는지 테스트합니다.
뮤텍스가 없는 경우 뮤텍스는 현재 사용자에게 뮤텍스를 사용할 수 있는 권한을 거부하지만 뮤텍스에 대한 읽기 및 변경 권한을 부여하는 초기 소유권 및 액세스 제어 보안으로 만들어집니다.
두 명령 창에서 컴파일된 예제를 실행하는 경우 두 번째 복사본은 호출에서 액세스 위반 예외를 throw합니다 OpenExisting(String). 예외가 catch되고, 이 예제에서는 메서드 오버로드를 사용하여 OpenExisting(String, MutexRights) 권한 및 메서드를 사용하여 사용 권한을 읽고 변경하는 데 필요한 권한으로 뮤텍스를 GetAccessControlSetAccessControl 엽니다.
사용 권한이 변경되면 뮤텍스를 입력하고 해제하는 데 필요한 권한으로 뮤텍스가 열립니다. 세 번째 명령 창에서 컴파일된 예제를 실행하면 새 사용 권한을 사용하여 실행됩니다.
using System;
using System.Threading;
using System.Security.AccessControl;
internal class Example
{
internal static void Main()
{
const string mutexName = "MutexExample4";
Mutex m = null;
bool doesNotExist = false;
bool unauthorized = false;
// The value of this variable is set by the mutex
// constructor. It is true if the named system mutex was
// created, and false if the named mutex already existed.
//
bool mutexWasCreated = false;
// Attempt to open the named mutex.
try
{
// Open the mutex with (MutexRights.Synchronize |
// MutexRights.Modify), to enter and release the
// named mutex.
//
m = Mutex.OpenExisting(mutexName);
}
catch(WaitHandleCannotBeOpenedException)
{
Console.WriteLine("Mutex does not exist.");
doesNotExist = true;
}
catch(UnauthorizedAccessException ex)
{
Console.WriteLine("Unauthorized access: {0}", ex.Message);
unauthorized = true;
}
// There are three cases: (1) The mutex does not exist.
// (2) The mutex exists, but the current user doesn't
// have access. (3) The mutex exists and the user has
// access.
//
if (doesNotExist)
{
// The mutex does not exist, so create it.
// Create an access control list (ACL) that denies the
// current user the right to enter or release the
// mutex, but allows the right to read and change
// security information for the mutex.
//
string user = Environment.UserDomainName + "\\"
+ Environment.UserName;
var mSec = new MutexSecurity();
MutexAccessRule rule = new MutexAccessRule(user,
MutexRights.Synchronize | MutexRights.Modify,
AccessControlType.Deny);
mSec.AddAccessRule(rule);
rule = new MutexAccessRule(user,
MutexRights.ReadPermissions | MutexRights.ChangePermissions,
AccessControlType.Allow);
mSec.AddAccessRule(rule);
// Create a Mutex object that represents the system
// mutex named by the constant 'mutexName', with
// initial ownership for this thread, and with the
// specified security access. The Boolean value that
// indicates creation of the underlying system object
// is placed in mutexWasCreated.
//
m = new Mutex(true, mutexName, out mutexWasCreated, mSec);
// If the named system mutex was created, it can be
// used by the current instance of this program, even
// though the current user is denied access. The current
// program owns the mutex. Otherwise, exit the program.
//
if (mutexWasCreated)
{
Console.WriteLine("Created the mutex.");
}
else
{
Console.WriteLine("Unable to create the mutex.");
return;
}
}
else if (unauthorized)
{
// Open the mutex to read and change the access control
// security. The access control security defined above
// allows the current user to do this.
//
try
{
m = Mutex.OpenExisting(mutexName,
MutexRights.ReadPermissions | MutexRights.ChangePermissions);
// Get the current ACL. This requires
// MutexRights.ReadPermissions.
MutexSecurity mSec = m.GetAccessControl();
string user = Environment.UserDomainName + "\\"
+ Environment.UserName;
// First, the rule that denied the current user
// the right to enter and release the mutex must
// be removed.
MutexAccessRule rule = new MutexAccessRule(user,
MutexRights.Synchronize | MutexRights.Modify,
AccessControlType.Deny);
mSec.RemoveAccessRule(rule);
// Now grant the user the correct rights.
//
rule = new MutexAccessRule(user,
MutexRights.Synchronize | MutexRights.Modify,
AccessControlType.Allow);
mSec.AddAccessRule(rule);
// Update the ACL. This requires
// MutexRights.ChangePermissions.
m.SetAccessControl(mSec);
Console.WriteLine("Updated mutex security.");
// Open the mutex with (MutexRights.Synchronize
// | MutexRights.Modify), the rights required to
// enter and release the mutex.
//
m = Mutex.OpenExisting(mutexName);
}
catch(UnauthorizedAccessException ex)
{
Console.WriteLine("Unable to change permissions: {0}",
ex.Message);
return;
}
}
// If this program created the mutex, it already owns
// the mutex.
//
if (!mutexWasCreated)
{
// Enter the mutex, and hold it until the program
// exits.
//
try
{
Console.WriteLine("Wait for the mutex.");
m.WaitOne();
Console.WriteLine("Entered the mutex.");
}
catch(UnauthorizedAccessException ex)
{
Console.WriteLine("Unauthorized access: {0}", ex.Message);
}
}
Console.WriteLine("Press the Enter key to exit.");
Console.ReadLine();
m.ReleaseMutex();
m.Dispose();
}
}
Imports System.Threading
Imports System.Security.AccessControl
Friend Class Example
<MTAThread> _
Friend Shared Sub Main()
Const mutexName As String = "MutexExample4"
Dim m As Mutex = Nothing
Dim doesNotExist as Boolean = False
Dim unauthorized As Boolean = False
' The value of this variable is set by the mutex
' constructor. It is True if the named system mutex was
' created, and False if the named mutex already existed.
'
Dim mutexWasCreated As Boolean
' Attempt to open the named mutex.
Try
' Open the mutex with (MutexRights.Synchronize Or
' MutexRights.Modify), to enter and release the
' named mutex.
'
m = Mutex.OpenExisting(mutexName)
Catch ex As WaitHandleCannotBeOpenedException
Console.WriteLine("Mutex does not exist.")
doesNotExist = True
Catch ex As UnauthorizedAccessException
Console.WriteLine("Unauthorized access: {0}", ex.Message)
unauthorized = True
End Try
' There are three cases: (1) The mutex does not exist.
' (2) The mutex exists, but the current user doesn't
' have access. (3) The mutex exists and the user has
' access.
'
If doesNotExist Then
' The mutex does not exist, so create it.
' Create an access control list (ACL) that denies the
' current user the right to enter or release the
' mutex, but allows the right to read and change
' security information for the mutex.
'
Dim user As String = Environment.UserDomainName _
& "\" & Environment.UserName
Dim mSec As New MutexSecurity()
Dim rule As New MutexAccessRule(user, _
MutexRights.Synchronize Or MutexRights.Modify, _
AccessControlType.Deny)
mSec.AddAccessRule(rule)
rule = New MutexAccessRule(user, _
MutexRights.ReadPermissions Or _
MutexRights.ChangePermissions, _
AccessControlType.Allow)
mSec.AddAccessRule(rule)
' Create a Mutex object that represents the system
' mutex named by the constant 'mutexName', with
' initial ownership for this thread, and with the
' specified security access. The Boolean value that
' indicates creation of the underlying system object
' is placed in mutexWasCreated.
'
m = New Mutex(True, mutexName, mutexWasCreated, mSec)
' If the named system mutex was created, it can be
' used by the current instance of this program, even
' though the current user is denied access. The current
' program owns the mutex. Otherwise, exit the program.
'
If mutexWasCreated Then
Console.WriteLine("Created the mutex.")
Else
Console.WriteLine("Unable to create the mutex.")
Return
End If
ElseIf unauthorized Then
' Open the mutex to read and change the access control
' security. The access control security defined above
' allows the current user to do this.
'
Try
m = Mutex.OpenExisting(mutexName, _
MutexRights.ReadPermissions Or _
MutexRights.ChangePermissions)
' Get the current ACL. This requires
' MutexRights.ReadPermissions.
Dim mSec As MutexSecurity = m.GetAccessControl()
Dim user As String = Environment.UserDomainName _
& "\" & Environment.UserName
' First, the rule that denied the current user
' the right to enter and release the mutex must
' be removed.
Dim rule As New MutexAccessRule(user, _
MutexRights.Synchronize Or MutexRights.Modify, _
AccessControlType.Deny)
mSec.RemoveAccessRule(rule)
' Now grant the user the correct rights.
'
rule = New MutexAccessRule(user, _
MutexRights.Synchronize Or MutexRights.Modify, _
AccessControlType.Allow)
mSec.AddAccessRule(rule)
' Update the ACL. This requires
' MutexRights.ChangePermissions.
m.SetAccessControl(mSec)
Console.WriteLine("Updated mutex security.")
' Open the mutex with (MutexRights.Synchronize
' Or MutexRights.Modify), the rights required to
' enter and release the mutex.
'
m = Mutex.OpenExisting(mutexName)
Catch ex As UnauthorizedAccessException
Console.WriteLine("Unable to change permissions: {0}", _
ex.Message)
Return
End Try
End If
' If this program created the mutex, it already owns
' the mutex.
'
If Not mutexWasCreated Then
' Enter the mutex, and hold it until the program
' exits.
'
Try
Console.WriteLine("Wait for the mutex.")
m.WaitOne()
Console.WriteLine("Entered the mutex.")
Catch ex As UnauthorizedAccessException
Console.WriteLine("Unauthorized access: {0}", _
ex.Message)
End Try
End If
Console.WriteLine("Press the Enter key to exit.")
Console.ReadLine()
m.ReleaseMutex()
m.Dispose()
End Sub
End Class
설명
이 메서드는 GetAccessControl 다음과 같은 플래그 조합(비트 OR 연산을 사용하여 결합됨)을 사용하여 사용 권한을 검색합니다. AccessControlSections.AccessAccessControlSections.OwnerAccessControlSections.Group
사용자가 이 메서드를 호출해야 MutexRights.ReadPermissions 하며 뮤텍스가 .로 열려 MutexRights.ReadPermissions있어야 합니다.
메모
.NET Core 및 .NET 5 이상에서 해당 메서드는 GetAccessControl.