PrincipalPermissionMode Enumeração

Definição

public enum class PrincipalPermissionMode

public enum PrincipalPermissionMode

type PrincipalPermissionMode = 

Public Enum PrincipalPermissionMode

Herança

Object

ValueType

Enum

PrincipalPermissionMode

Campos

Exemplos

O exemplo seguinte mostra como especificar 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

O exemplo seguinte mostra como especificar o Personalizado.

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

Observações

Ao aplicar o PrincipalPermissionAttribute a um método, este modo especifica qual o conjunto de funções a usar ao autorizar o acesso. Por defeito, o atributo utiliza Windows grupos (como Administrator ou Users) para especificar o papel ao qual o utilizador deve pertencer.

Para definir o modo programaticamente, crie uma instância da ServiceHost classe, depois encontre o ServiceAuthorizationBehavior na sua coleção de comportamentos e defina o PrincipalPermissionMode para a enumeração apropriada. O exemplo seguinte define a propriedade como 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

Também pode definir o comportamento em configuração adicionando uma <ServiceAuthorization> aos <serviceBehaviors de um ficheiro de configuração, como mostrado> no código seguinte.

// 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

A enumeração afeta a forma como o PrincipalPermissionAttribute atributo autoriza um utilizador quando é aplicado a um método. O exemplo seguinte aplica o atributo a um método e exige que o utilizador pertença ao grupo Users no computador. Este código só funciona quando o PrincipalPermissionMode está definido como UseWindowsGroup (a definição padrão).

// 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

O valor UseAspNetRoles é usado para todos os tipos de credenciais. Este modo permite que a Windows Communication Foundation (WCF) utilize o fornecedor de funções ASP.NET para tomar decisões de autorização.

Quando a credencial de um serviço é um certificado X.509, pode definir a Name propriedade de para PrincipalPermissionAttribute uma string que consiste nos valores concatenados do campo Sujeito e do campo Impressão digital, como mostrado no exemplo seguinte.

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

A cadeia concatenada consiste nos valores do sujeito e da impressão digital do polegar separados por um ponto e vírgula e um espaço.

Também é possível que um certificado tenha um campo Sujeito definido para uma cadeia nula. Nesse caso, pode definir a Name propriedade com um ponto e vírgula seguido de um espaço e depois a impressão digital, como mostrado no exemplo seguinte.

// 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

Se houver um fornecedor de funções ASP.NET, também pode definir a propriedade Role para um papel na base de dados. Por defeito, a base de dados é representada pelo SqlRoleProvider. Também pode definir um fornecedor de papéis personalizado com a RoleProvider propriedade da ServiceAuthorizationBehavior classe. O código seguinte define o papel como Administrators. Note que o fornecedor de funções deve mapear a conta de utilizador para essa função.

[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

Para mais informações sobre a utilização do WCF e o fornecedor de funções, consulte Como: Utilizar o Fornecedor de Funções ASP.NET com um Service.

Personalizado

Quando a propriedade está definida para Custom, também deve fornecer uma classe personalizada que implemente a IAuthorizationPolicy classe. Esta classe é responsável por fornecer a representação do IPrincipal chamador dentro da Properties coleção. Deve armazenar a IPrincipal instância na coleção de propriedades usando a chave de string "Principal", como mostrado no exemplo seguinte.

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

Contexto geral

A segurança baseada em funções no .NET Framework permite que as aplicações especifiquem autorizações através de código. Ao especificar a PrincipalPermission procura, deve CurrentPrincipal satisfazer o PrincipalPermission requisito. Por exemplo, que o utilizador deve estar num papel ou grupo específico. Caso contrário, o thread não está autorizado a executar o código, o que resulta numa exceção. A WCF fornece um conjunto de PrincipalPermissionMode seleções para especificar as CurrentPrincipal baseadas SecurityContext em conformidade.