PrincipalPermissionMode PrincipalPermissionMode PrincipalPermissionMode PrincipalPermissionMode Enum

Definition

Sets the mode for authorization checks when using the PrincipalPermissionAttribute to control access to a method.

public enum class PrincipalPermissionMode
public enum PrincipalPermissionMode
type PrincipalPermissionMode = 
Public Enum PrincipalPermissionMode
Inheritance
PrincipalPermissionModePrincipalPermissionModePrincipalPermissionModePrincipalPermissionMode

Fields

Always Always Always Always 4

Always enables the user to specify a IPrincipal class for CurrentPrincipal.

Custom Custom Custom Custom 3

Enables the user to specify a custom IPrincipal class for CurrentPrincipal.

None None None None 0

CurrentPrincipal is not set.

UseAspNetRoles UseAspNetRoles UseAspNetRoles UseAspNetRoles 2

CurrentPrincipal is set based on the ASP.NET role provider (RoleProvider).

UseWindowsGroups UseWindowsGroups UseWindowsGroups UseWindowsGroups 1

CurrentPrincipal is set based on Windows (WindowsPrincipal). If the user identity is not associated with a Windows account, anonymous Windows is used.

Examples

The following example shows how to specify UseAspNetRoles.

namespace TestPrincipalPermission
{
    class PrincipalPermissionModeWindows
    {
    
        [ServiceContract]
        interface ISecureService
        {
            [OperationContract]
            string Method1();
        }
                
        class SecureService : ISecureService
        {
            [PrincipalPermission(SecurityAction.Demand, Role = "everyone")]
            public string Method1()
            {
                return String.Format("Hello, \"{0}\"", Thread.CurrentPrincipal.Identity.Name);
            }
        }

        public void Run()
        {
            Uri serviceUri = new Uri(@"http://localhost:8006/Service");
            ServiceHost service = new ServiceHost(typeof(SecureService));
            service.AddServiceEndpoint(typeof(ISecureService), GetBinding(), serviceUri);
            service.Authorization.PrincipalPermissionMode = PrincipalPermissionMode.UseAspNetRoles;
            service.Open();

            EndpointAddress sr = new EndpointAddress(
                serviceUri, EndpointIdentity.CreateUpnIdentity(WindowsIdentity.GetCurrent().Name));
            ChannelFactory<ISecureService> cf = new ChannelFactory<ISecureService>(GetBinding(), sr);
            ISecureService client = cf.CreateChannel();
            Console.WriteLine("Client received response from Method1: {0}", client.Method1());
            ((IChannel)client).Close();
            Console.ReadLine();
            service.Close();
            
        }

        public static Binding GetBinding()
        {
            WSHttpBinding binding = new WSHttpBinding(SecurityMode.Message);
            binding.Security.Message.ClientCredentialType = MessageCredentialType.Windows;
            return binding;
        }
    }
}
Namespace TestPrincipalPermission
    Friend Class PrincipalPermissionModeWindows

        <ServiceContract> _
        Private Interface ISecureService
            <OperationContract> _
            Function Method1() As String
        End Interface

        Private Class SecureService
            Implements ISecureService
            <PrincipalPermission(SecurityAction.Demand, Role:="everyone")> _
            Public Function Method1() As String Implements ISecureService.Method1
                Return String.Format("Hello, ""{0}""", Thread.CurrentPrincipal.Identity.Name)
            End Function

        End Class

        Public Sub Run()
            Dim serviceUri As New Uri("http://localhost:8006/Service")
            Dim service As New ServiceHost(GetType(SecureService))
            service.AddServiceEndpoint(GetType(ISecureService), GetBinding(), serviceUri)
            service.Authorization.PrincipalPermissionMode = PrincipalPermissionMode.UseAspNetRoles
            service.Open()

            Dim sr As New EndpointAddress(serviceUri, EndpointIdentity.CreateUpnIdentity(WindowsIdentity.GetCurrent().Name))
            Dim cf As New ChannelFactory(Of ISecureService)(GetBinding(), sr)
            Dim client As ISecureService = cf.CreateChannel()
            Console.WriteLine("Client received response from Method1: {0}", client.Method1())
            CType(client, IChannel).Close()
            Console.ReadLine()
            service.Close()

        End Sub

        Public Shared Function GetBinding() As Binding
            Dim binding As New WSHttpBinding(SecurityMode.Message)
            binding.Security.Message.ClientCredentialType = MessageCredentialType.Windows
            Return binding
        End Function
    End Class
End Namespace

The following example shows how to specify Custom.

namespace CustomMode
{
    public class Test
    {
        public static void Main()
        {
            try
            {
                ShowPrincipalPermissionModeCustom ppwm = new ShowPrincipalPermissionModeCustom();
                ppwm.Run();

            }
            catch (Exception exc)
            {
                Console.WriteLine("Error: {0}", exc.Message);
                Console.ReadLine();
            }
        }
    }

    class ShowPrincipalPermissionModeCustom
    {
        [ServiceContract]
        interface ISecureService
        {
            [OperationContract]
            string Method1(string request);
        }

        [ServiceBehavior]
        class SecureService : ISecureService
        {
            [PrincipalPermission(SecurityAction.Demand, Role = "everyone")]
            public string Method1(string request)
            {
                return String.Format("Hello, \"{0}\"", Thread.CurrentPrincipal.Identity.Name);
            }
        }

        public void Run()
        {
            Uri serviceUri = new Uri(@"http://localhost:8006/Service");
            ServiceHost service = new ServiceHost(typeof(SecureService));
            service.AddServiceEndpoint(typeof(ISecureService), GetBinding(), serviceUri);
            List<IAuthorizationPolicy> policies = new List<IAuthorizationPolicy>();
            policies.Add(new CustomAuthorizationPolicy());
            service.Authorization.ExternalAuthorizationPolicies = policies.AsReadOnly();
            service.Authorization.PrincipalPermissionMode = PrincipalPermissionMode.Custom;
            service.Open();

            EndpointAddress sr = new EndpointAddress(
                serviceUri, EndpointIdentity.CreateUpnIdentity(WindowsIdentity.GetCurrent().Name));
            ChannelFactory<ISecureService> cf = new ChannelFactory<ISecureService>(GetBinding(), sr);
            ISecureService client = cf.CreateChannel();
            Console.WriteLine("Client received response from Method1: {0}", client.Method1("hello"));
            ((IChannel)client).Close();
            Console.ReadLine();
            service.Close();            
        }

        public static Binding GetBinding()
        {
            WSHttpBinding binding = new WSHttpBinding(SecurityMode.Message);
            binding.Security.Message.ClientCredentialType = MessageCredentialType.Windows;
            return binding;
        }

        class CustomAuthorizationPolicy : IAuthorizationPolicy
        {
            string id = Guid.NewGuid().ToString();

            public string Id
            {
                get { return this.id; }
            }

            public ClaimSet Issuer
            {
                get { return ClaimSet.System; }
            }

            public bool Evaluate(EvaluationContext context, ref object state)
            {
                object obj;
                if (!context.Properties.TryGetValue("Identities", out obj))
                    return false;

                IList<IIdentity> identities = obj as IList<IIdentity>;
                if (obj == null || identities.Count <= 0)
                    return false;

                context.Properties["Principal"] = new CustomPrincipal(identities[0]);
                return true;
            }
        }

        class CustomPrincipal : IPrincipal
        {
            IIdentity identity;
            public CustomPrincipal(IIdentity identity)
            {
                this.identity = identity;
            }

            public IIdentity Identity
            {
                get { return this.identity; }
            }

            public bool IsInRole(string role)
            {
                return true;
            }
        }
    }
}
Namespace CustomMode
    Public Class Test
        Public Shared Sub Main()
            Try
                Dim ppwm As New ShowPrincipalPermissionModeCustom()
                ppwm.Run()

            Catch exc As Exception
                Console.WriteLine("Error: {0}", exc.Message)
                Console.ReadLine()
            End Try
        End Sub
    End Class

    Friend Class ShowPrincipalPermissionModeCustom
        <ServiceContract> _
        Private Interface ISecureService
            <OperationContract> _
            Function Method1(ByVal request As String) As String
        End Interface

        <ServiceBehavior> _
        Private Class SecureService
            Implements ISecureService
            <PrincipalPermission(SecurityAction.Demand, Role:="everyone")> _
            Public Function Method1(ByVal request As String) As String Implements ISecureService.Method1
                Return String.Format("Hello, ""{0}""", Thread.CurrentPrincipal.Identity.Name)
            End Function
        End Class

        Public Sub Run()
            Dim serviceUri As New Uri("http://localhost:8006/Service")
            Dim service As New ServiceHost(GetType(SecureService))
            service.AddServiceEndpoint(GetType(ISecureService), GetBinding(), serviceUri)
            Dim policies As New List(Of IAuthorizationPolicy)()
            policies.Add(New CustomAuthorizationPolicy())
            service.Authorization.ExternalAuthorizationPolicies = policies.AsReadOnly()
            service.Authorization.PrincipalPermissionMode = PrincipalPermissionMode.Custom
            service.Open()

            Dim sr As New EndpointAddress(serviceUri, EndpointIdentity.CreateUpnIdentity(WindowsIdentity.GetCurrent().Name))
            Dim cf As New ChannelFactory(Of ISecureService)(GetBinding(), sr)
            Dim client As ISecureService = cf.CreateChannel()
            Console.WriteLine("Client received response from Method1: {0}", client.Method1("hello"))
            CType(client, IChannel).Close()
            Console.ReadLine()
            service.Close()
        End Sub

        Public Shared Function GetBinding() As Binding
            Dim binding As New WSHttpBinding(SecurityMode.Message)
            binding.Security.Message.ClientCredentialType = MessageCredentialType.Windows
            Return binding
        End Function

        Private Class CustomAuthorizationPolicy
            Implements IAuthorizationPolicy
            Private id_Renamed As String = Guid.NewGuid().ToString()

            Public ReadOnly Property Id() As String Implements System.IdentityModel.Policy.IAuthorizationComponent.Id
                Get
                    Return Me.id_Renamed
                End Get
            End Property

            Public ReadOnly Property Issuer() As ClaimSet Implements IAuthorizationPolicy.Issuer
                Get
                    Return ClaimSet.System
                End Get
            End Property

            Public Function Evaluate(ByVal context As EvaluationContext, ByRef state As Object) As Boolean Implements IAuthorizationPolicy.Evaluate
                Dim obj As Object = Nothing
                If (Not context.Properties.TryGetValue("Identities", obj)) Then
                    Return False
                End If

                Dim identities As IList(Of IIdentity) = TryCast(obj, IList(Of IIdentity))
                If obj Is Nothing OrElse identities.Count <= 0 Then
                    Return False
                End If

                context.Properties("Principal") = New CustomPrincipal(identities(0))
                Return True
            End Function
        End Class

        Private Class CustomPrincipal
            Implements IPrincipal
            Private identity_Renamed As IIdentity
            Public Sub New(ByVal identity As IIdentity)
                Me.identity_Renamed = identity
            End Sub

            Public ReadOnly Property Identity() As IIdentity Implements IPrincipal.Identity
                Get
                    Return Me.identity_Renamed
                End Get
            End Property

            Public Function IsInRole(ByVal role As String) As Boolean Implements IPrincipal.IsInRole
                Return True
            End Function
        End Class
    End Class
End Namespace

Remarks

When applying the PrincipalPermissionAttribute to a method, this mode specifies which set of roles to use when authorizing access. By default, the attribute uses Windows groups (such as Administrator or Users) to specify the role to which the user must belong.

To set the mode programmatically, create an instance of the ServiceHost class, then find the ServiceAuthorizationBehavior in its collection of behaviors, and set the PrincipalPermissionMode to the appropriate enumeration. The following example sets the property to UseAspNetRoles.

ServiceHost myServiceHost = new ServiceHost(typeof(Calculator), baseUri);
ServiceAuthorizationBehavior myServiceBehavior =
    myServiceHost.Description.Behaviors.Find<ServiceAuthorizationBehavior>();
myServiceBehavior.PrincipalPermissionMode =
    PrincipalPermissionMode.UseAspNetRoles;
Dim myServiceHost As New ServiceHost(GetType(Calculator), baseUri)
Dim myServiceBehavior As ServiceAuthorizationBehavior = myServiceHost.Description.Behaviors.Find(Of ServiceAuthorizationBehavior)()
myServiceBehavior.PrincipalPermissionMode = PrincipalPermissionMode.UseAspNetRoles

You can also set the behavior in configuration by adding a <serviceAuthorization> to the <serviceBehaviors> of a configuration file, as shown in the following code.

// Only a client authenticated with a valid certificate that has the 
// specified subject name and thumbprint can call this method.
[PrincipalPermission(SecurityAction.Demand,
     Name = "CN=ReplaceWithSubjectName; 123456712345677E8E230FDE624F841B1CE9D41E")]
public double Multiply(double a, double b)
{
    return a * b;
}
' Only a client authenticated with a valid certificate that has the 
' specified subject name and thumbprint can call this method.
<PrincipalPermission(SecurityAction.Demand, Name := "CN=ReplaceWithSubjectName; 123456712345677E8E230FDE624F841B1CE9D41E")> _
Public Function Multiply(ByVal a As Double, ByVal b As Double) As Double
    Return a * b
End Function

The enumeration affects how the PrincipalPermissionAttribute attribute authorizes a user when it is applied to a method. The following example applies the attribute to a method and demands that the user belong to the Users group on the computer. This code works only when the PrincipalPermissionMode is set to UseWindowsGroup (the default setting).

// Only members of the CalculatorClients group can call this method.
[PrincipalPermission(SecurityAction.Demand, Role = "Users")]
public double Add(double a, double b)
{
    return a + b;
}
' Only members of the CalculatorClients group can call this method.
<PrincipalPermission(SecurityAction.Demand, Role := "Users")> _
Public Function Add(ByVal a As Double, ByVal b As Double) As Double
    Return a + b
End Function

UseAspNetRoles

The UseAspNetRoles value is used for all credential types. This mode enables Windows Communication Foundation (WCF) to use the ASP.NET role provider to make authorization decisions.

When the credential for a service is an X.509 certificate, you can set the Name property of the PrincipalPermissionAttribute to a string that consists of the concatenated values of the Subject field and the Thumbprint field, as shown in the following example.

ServiceHost myServiceHost = new ServiceHost(typeof(Calculator), baseUri);
ServiceAuthorizationBehavior myServiceBehavior =
    myServiceHost.Description.Behaviors.Find<ServiceAuthorizationBehavior>();
myServiceBehavior.PrincipalPermissionMode =
    PrincipalPermissionMode.UseAspNetRoles;
MyServiceAuthorizationManager sm = new MyServiceAuthorizationManager();
myServiceBehavior.ServiceAuthorizationManager = sm;
Dim myServiceHost As New ServiceHost(GetType(Calculator), baseUri)
Dim myServiceBehavior As ServiceAuthorizationBehavior = myServiceHost.Description.Behaviors.Find(Of ServiceAuthorizationBehavior)()
myServiceBehavior.PrincipalPermissionMode = PrincipalPermissionMode.UseAspNetRoles
Dim sm As New MyServiceAuthorizationManager()
myServiceBehavior.ServiceAuthorizationManager = sm

The concatenated string consists of the subject and thumbprint values separated by a semicolon and a space.

It is also possible for a certificate to have a Subject field set to a null string. In that case, you can set the Name property to a semicolon followed by a space and then the thumbprint, as shown in the following example.

// Only a client authenticated with a valid certificate that has the 
// specified thumbprint can call this method.
[PrincipalPermission(SecurityAction.Demand,
     Name = "; 123456712345677E8E230FDE624F841B1CE9D41E")]
public double Divide(double a, double b)
{
    return a * b;
}
' Only a client authenticated with a valid certificate that has the 
' specified thumbprint can call this method.
<PrincipalPermission(SecurityAction.Demand, Name := "; 123456712345677E8E230FDE624F841B1CE9D41E")> _
Public Function Divide(ByVal a As Double, ByVal b As Double) As Double
    Return a * b
End Function

If an ASP.NET role provider is present, you can also set the Role property to a role in the database. By default, the database is represented by the SqlRoleProvider. You can also set a custom role provider with the RoleProvider property of the ServiceAuthorizationBehavior class. The following code sets the role to Administrators. Note that the role provider must map the user account to that role.

[PrincipalPermission(SecurityAction.Demand, Role = "Administrators")]
public string ReadFile(string fileName)
{
    // Code not shown.
    return "Not implemented";
}
<PrincipalPermission(SecurityAction.Demand, Role := "Administrators")> _
Public Function ReadFile(ByVal fileName As String) As String
    ' Code not shown.
    Return "Not implemented"
End Function

For more information about the ASP.NET Role provider, see How To: Use Role Manager in ASP.NET 2.0.

For more information about using WCF and the role provider, see How to: Use the ASP.NET Role Provider with a Service.

Custom

When the property is set to Custom, you must also provide a custom class that implements the IAuthorizationPolicy class. This class is responsible for providing the caller's IPrincipal representation inside the Properties collection. It must store the IPrincipal instance to the properties collection using the "Principal" string key, as shown in the following example.

evaluationContext.Properties["Principal"]=new CustomPrincipal(identity);  

Background

The role-based security in .NET Framework enables applications to specify authorizations through code. By specifying the PrincipalPermission demand, the CurrentPrincipal must satisfy the PrincipalPermission requirement. For example, that the user must be in a specific role or group. Otherwise, the thread is not authorized to execute the code, which results in an exception. WCF provides a set of PrincipalPermissionMode selections to specify the CurrentPrincipal based on SecurityContext accordingly.

Applies to