DnsPermissionAttribute Class
Important
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Caution
Code Access Security is not supported or honored by the runtime.
Specifies permission to request information from Domain Name Servers.
public ref class DnsPermissionAttribute sealed : System::Security::Permissions::CodeAccessSecurityAttribute
[System.AttributeUsage(System.AttributeTargets.Assembly | System.AttributeTargets.Class | System.AttributeTargets.Constructor | System.AttributeTargets.Method | System.AttributeTargets.Struct, AllowMultiple=true, Inherited=false)]
[System.Obsolete("Code Access Security is not supported or honored by the runtime.", DiagnosticId="SYSLIB0003", UrlFormat="https://aka.ms/dotnet-warnings/{0}")]
public sealed class DnsPermissionAttribute : System.Security.Permissions.CodeAccessSecurityAttribute
[System.AttributeUsage(System.AttributeTargets.Assembly | System.AttributeTargets.Class | System.AttributeTargets.Constructor | System.AttributeTargets.Method | System.AttributeTargets.Struct, AllowMultiple=true, Inherited=false)]
[System.Serializable]
public sealed class DnsPermissionAttribute : System.Security.Permissions.CodeAccessSecurityAttribute
[System.AttributeUsage(System.AttributeTargets.Assembly | System.AttributeTargets.Class | System.AttributeTargets.Constructor | System.AttributeTargets.Method | System.AttributeTargets.Struct, AllowMultiple=true, Inherited=false)]
public sealed class DnsPermissionAttribute : System.Security.Permissions.CodeAccessSecurityAttribute
[<System.AttributeUsage(System.AttributeTargets.Assembly | System.AttributeTargets.Class | System.AttributeTargets.Constructor | System.AttributeTargets.Method | System.AttributeTargets.Struct, AllowMultiple=true, Inherited=false)>]
[<System.Obsolete("Code Access Security is not supported or honored by the runtime.", DiagnosticId="SYSLIB0003", UrlFormat="https://aka.ms/dotnet-warnings/{0}")>]
type DnsPermissionAttribute = class
inherit CodeAccessSecurityAttribute
[<System.AttributeUsage(System.AttributeTargets.Assembly | System.AttributeTargets.Class | System.AttributeTargets.Constructor | System.AttributeTargets.Method | System.AttributeTargets.Struct, AllowMultiple=true, Inherited=false)>]
[<System.Serializable>]
type DnsPermissionAttribute = class
inherit CodeAccessSecurityAttribute
[<System.AttributeUsage(System.AttributeTargets.Assembly | System.AttributeTargets.Class | System.AttributeTargets.Constructor | System.AttributeTargets.Method | System.AttributeTargets.Struct, AllowMultiple=true, Inherited=false)>]
type DnsPermissionAttribute = class
inherit CodeAccessSecurityAttribute
Public NotInheritable Class DnsPermissionAttribute
Inherits CodeAccessSecurityAttribute
- Inheritance
- Attributes
The following example uses DnsPermissionAttribute to apply declarative security to a custom class.
//Uses the DnsPermissionAttribute to restrict access only to those who have permission.
[DnsPermission(SecurityAction::Demand,Unrestricted=true)]
public ref class MyClass
{
public:
static IPAddress^ GetIPAddress()
{
IPAddress^ ipAddress = Dns::Resolve( "localhost" )->AddressList[ 0 ];
return ipAddress;
}
};
int main()
{
try
{
//Grants Access.
Console::WriteLine( " Access granted\n The local host IP Address is :{0}", MyClass::GetIPAddress() );
}
// Denies Access.
catch ( SecurityException^ securityException )
{
Console::WriteLine( "Access denied" );
Console::WriteLine( securityException->ToString() );
}
}
public class MyClass
{
public static IPAddress GetIPAddress()
{
IPAddress ipAddress = Dns.Resolve("localhost").AddressList[0];
return ipAddress;
}
public static void Main()
{
try
{
//Grants Access.
Console.WriteLine(" Access granted\n The local host IP Address is :" +
MyClass.GetIPAddress().ToString());
}
// Denies Access.
catch (SecurityException securityException)
{
Console.WriteLine("Access denied");
Console.WriteLine(securityException.ToString());
}
}
}
' Uses the DnsPermissionAttribute to restrict access only to those who have permission.
<DnsPermission(SecurityAction.Demand, Unrestricted := true)> _
Public Class MyClass1
Public Shared Function GetIPAddress() As IPAddress
Dim ipAddress As IPAddress = Dns.Resolve("localhost").AddressList(0)
Return ipAddress
End Function 'GetIPAddress
Public Shared Sub Main()
Try
' Grants Access.
Console.WriteLine(("Access granted" + ControlChars.NewLine + " The local host IP Address is :" + MyClass1.GetIPAddress().ToString()))
' Denies Access.
Catch securityException As SecurityException
Console.WriteLine("Access denied")
Console.WriteLine(securityException.ToString())
End Try
End Sub
End Class
Caution
Code Access Security (CAS) has been deprecated across all versions of .NET Framework and .NET. Recent versions of .NET do not honor CAS annotations and produce errors if CAS-related APIs are used. Developers should seek alternative means of accomplishing security tasks.
The security information declared by DnsPermissionAttribute is stored in the metadata of the attribute target, which is the class to which the DnsPermissionAttribute is applied. The system then accesses this information at run time. The SecurityAction that is passed to the constructor determines the allowable DNS targets.
These security attributes are used only for Declarative Security. For Imperative Security, use the corresponding DnsPermission class.
Security access is either fully restricted or fully unrestricted. Set the Unrestricted property to true
to grant access, or false
for no access. Set this property as a named parameter.
For more information about using attributes, see Attributes.
Dns |
Initializes a new instance of the DnsPermissionAttribute class with the specified SecurityAction value. |
Action |
Gets or sets a security action. (Inherited from SecurityAttribute) |
Type |
When implemented in a derived class, gets a unique identifier for this Attribute. (Inherited from Attribute) |
Unrestricted |
Gets or sets a value indicating whether full (unrestricted) permission to the resource protected by the attribute is declared. (Inherited from SecurityAttribute) |
Create |
Creates and returns a new instance of the DnsPermission class. |
Equals(Object) |
Returns a value that indicates whether this instance is equal to a specified object. (Inherited from Attribute) |
Get |
Returns the hash code for this instance. (Inherited from Attribute) |
Get |
Gets the Type of the current instance. (Inherited from Object) |
Is |
When overridden in a derived class, indicates whether the value of this instance is the default value for the derived class. (Inherited from Attribute) |
Match(Object) |
When overridden in a derived class, returns a value that indicates whether this instance equals a specified object. (Inherited from Attribute) |
Memberwise |
Creates a shallow copy of the current Object. (Inherited from Object) |
To |
Returns a string that represents the current object. (Inherited from Object) |
_Attribute. |
Maps a set of names to a corresponding set of dispatch identifiers. (Inherited from Attribute) |
_Attribute. |
Retrieves the type information for an object, which can be used to get the type information for an interface. (Inherited from Attribute) |
_Attribute. |
Retrieves the number of type information interfaces that an object provides (either 0 or 1). (Inherited from Attribute) |
_Attribute. |
Provides access to properties and methods exposed by an object. (Inherited from Attribute) |
Product | Versions (Obsolete) |
---|---|
.NET | (8 (package-provided), 9 (package-provided)) |
.NET Framework | 1.1, 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7 (package-provided), 4.7, 4.7.1 (package-provided), 4.7.1, 4.7.2 (package-provided), 4.7.2, 4.8 (package-provided), 4.8, 4.8.1 |
.NET Standard | 2.0 (package-provided) |
Windows Desktop | 3.0, 3.1 (5, 6, 7, 8, 9) |
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