MutexSecurity.RemoveAccessRuleAll(MutexAccessRule) Method

Definition

Namespace:

System.Security.AccessControl

Assembly:

System.Threading.AccessControl.dll

Source:

MutexSecurity.cs

Searches for all access control rules with the same user and AccessControlType (allow or deny) as the specified rule and, if found, removes them.

public:
 void RemoveAccessRuleAll(System::Security::AccessControl::MutexAccessRule ^ rule);

public void RemoveAccessRuleAll (System.Security.AccessControl.MutexAccessRule rule);

override this.RemoveAccessRuleAll : System.Security.AccessControl.MutexAccessRule -> unit

Public Sub RemoveAccessRuleAll (rule As MutexAccessRule)

Parameters

rule

MutexAccessRule

A MutexAccessRule that specifies the user and AccessControlType to search for. Any rights specified by this rule are ignored.

Exceptions

ArgumentNullException

rule is null.

Examples

The following code example shows that the RemoveAccessRuleAll method removes all rules that match user and AccessControlType, ignoring rights.

The example creates a MutexSecurity object, adds rules that allow and deny various rights for the current user, and then merges additional rights into the Allow rule. The example then creates a new rule that allows the current user to take ownership, and uses that rule to remove the Allow rule from the MutexSecurity object.

Note

This example does not attach the security object to a Mutex object. Examples that attach security objects can be found in Mutex.GetAccessControl and Mutex.SetAccessControl.

using System;
using System.Threading;
using System.Security.AccessControl;
using System.Security.Principal;

public class Example
{
    public static void Main()
    {
        // Create a string representing the current user.
        string user = Environment.UserDomainName + "\\" + 
            Environment.UserName;

        // Create a security object that grants no access.
        MutexSecurity mSec = new MutexSecurity();

        // Add a rule that grants the current user the 
        // right to enter or release the mutex.
        MutexAccessRule rule = new MutexAccessRule(user, 
            MutexRights.Synchronize | MutexRights.Modify, 
            AccessControlType.Allow);
        mSec.AddAccessRule(rule);

        // Add a rule that denies the current user the 
        // right to change permissions on the mutex.
        rule = new MutexAccessRule(user, 
            MutexRights.ChangePermissions, 
            AccessControlType.Deny);
        mSec.AddAccessRule(rule);

        // Display the rules in the security object.
        ShowSecurity(mSec);

        // Add a rule that allows the current user the 
        // right to read permissions on the mutex. This rule
        // is merged with the existing Allow rule.
        rule = new MutexAccessRule(user, 
            MutexRights.ReadPermissions, 
            AccessControlType.Allow);
        mSec.AddAccessRule(rule);

        ShowSecurity(mSec);

        // Create a rule that allows the current user to
        // change the owner of the mutex, and use that rule 
        // to remove the existing allow access rule from 
        // the MutexSecurity object, showing that the user
        // and access type must match, while the rights are
        // ignored.
        Console.WriteLine("Use RemoveAccessRuleAll to remove the Allow rule.");
        rule = new MutexAccessRule(user, 
            MutexRights.TakeOwnership, 
            AccessControlType.Allow);
        mSec.RemoveAccessRuleAll(rule);

        ShowSecurity(mSec);
    }

    private static void ShowSecurity(MutexSecurity security)
    {
        Console.WriteLine("\r\nCurrent access rules:\r\n");

        foreach(MutexAccessRule ar in 
            security.GetAccessRules(true, true, typeof(NTAccount)))
        {
            Console.WriteLine("        User: {0}", ar.IdentityReference);
            Console.WriteLine("        Type: {0}", ar.AccessControlType);
            Console.WriteLine("      Rights: {0}", ar.MutexRights);
            Console.WriteLine();
        }
    }
}

/*This code example produces output similar to following:

Current access rules:

        User: TestDomain\TestUser
        Type: Deny
      Rights: ChangePermissions

        User: TestDomain\TestUser
        Type: Allow
      Rights: Modify, Synchronize


Current access rules:

        User: TestDomain\TestUser
        Type: Deny
      Rights: ChangePermissions

        User: TestDomain\TestUser
        Type: Allow
      Rights: Modify, ReadPermissions, Synchronize

Use RemoveAccessRuleAll to remove the Allow rule.

Current access rules:

        User: TestDomain\TestUser
        Type: Deny
      Rights: ChangePermissions
 */

Imports System.Threading
Imports System.Security.AccessControl
Imports System.Security.Principal

Public Class Example

    Public Shared Sub Main()

        ' Create a string representing the current user.
        Dim user As String = Environment.UserDomainName _ 
            & "\" & Environment.UserName

        ' Create a security object that grants no access.
        Dim mSec As New MutexSecurity()

        ' Add a rule that grants the current user the 
        ' right to enter or release the mutex.
        Dim rule As New MutexAccessRule(user, _
            MutexRights.Synchronize _
            Or MutexRights.Modify, _
            AccessControlType.Allow)
        mSec.AddAccessRule(rule)

        ' Add a rule that denies the current user the 
        ' right to change permissions on the mutex.
        rule = New MutexAccessRule(user, _
            MutexRights.ChangePermissions, _
            AccessControlType.Deny)
        mSec.AddAccessRule(rule)

        ' Display the rules in the security object.
        ShowSecurity(mSec)

        ' Add a rule that allows the current user the 
        ' right to read permissions on the mutex. This rule
        ' is merged with the existing Allow rule.
        rule = New MutexAccessRule(user, _
            MutexRights.ReadPermissions, _
            AccessControlType.Allow)
        mSec.AddAccessRule(rule)

        ShowSecurity(mSec)

        ' Create a rule that allows the current user to
        ' change the owner of the mutex, and use that rule 
        ' to remove the existing allow access rule from 
        ' the MutexSecurity object, showing that the user
        ' and access type must match, while the rights are
        ' ignored.
        Console.WriteLine("Use RemoveAccessRuleAll to remove the Allow rule.")
        rule = New MutexAccessRule(user, _
            MutexRights.TakeOwnership, _
            AccessControlType.Allow)
        mSec.RemoveAccessRuleAll(rule)

        ShowSecurity(mSec)
        
    End Sub 

    Private Shared Sub ShowSecurity(ByVal security As MutexSecurity)
        Console.WriteLine(vbCrLf & "Current access rules:" & vbCrLf)

        For Each ar As MutexAccessRule In _
            security.GetAccessRules(True, True, GetType(NTAccount))

            Console.WriteLine("        User: {0}", ar.IdentityReference)
            Console.WriteLine("        Type: {0}", ar.AccessControlType)
            Console.WriteLine("      Rights: {0}", ar.MutexRights)
            Console.WriteLine()
        Next

    End Sub
End Class 

'This code example produces output similar to following:
'
'Current access rules:
'
'        User: TestDomain\TestUser
'        Type: Deny
'      Rights: ChangePermissions
'
'        User: TestDomain\TestUser
'        Type: Allow
'      Rights: Modify, Synchronize
'
'
'Current access rules:
'
'        User: TestDomain\TestUser
'        Type: Deny
'      Rights: ChangePermissions
'
'        User: TestDomain\TestUser
'        Type: Allow
'      Rights: Modify, ReadPermissions, Synchronize
'
'Use RemoveAccessRuleAll to remove the Allow rule.
'
'Current access rules:
'
'        User: TestDomain\TestUser
'        Type: Deny
'      Rights: ChangePermissions

Remarks

The current MutexSecurity object is searched for rules that have the same user and the same AccessControlType value as rule. Any rights specified by rule are ignored when performing this search. If no matching rules are found, no action is taken.