NegotiateStream Klas

Definitie

public ref class NegotiateStream : System::Net::Security::AuthenticatedStream

public class NegotiateStream : System.Net.Security.AuthenticatedStream

type NegotiateStream = class
    inherit AuthenticatedStream

Public Class NegotiateStream
Inherits AuthenticatedStream

Overname

Object

MarshalByRefObject

Stream

AuthenticatedStream

NegotiateStream

Voorbeelden

In het volgende voorbeeld ziet u de clientzijde van een client-serververbinding die gebruikmaakt van .NegotiateStream De client verifieert en verzendt asynchroon een bericht naar de server.

using System;
using System.Net;
using System.Net.Security;
using System.Net.Sockets;
using System.Text;

namespace Examples.NegotiateStreamExample
{
    public class ASynchronousAuthenticatingTcpClient
    {
        static TcpClient client = null;

        public static void Main(String[] args)
        {
            // Establish the remote endpoint for the socket.
            // For this example, use the local machine.
            IPHostEntry ipHostInfo = Dns.GetHostEntry("localhost");
            IPAddress ipAddress = ipHostInfo.AddressList[0];
            // Client and server use port 11000.
            IPEndPoint remoteEP = new IPEndPoint(ipAddress, 11000);
            // Create a TCP/IP socket.
            client = new TcpClient();
            // Connect the socket to the remote endpoint.
            client.Connect(remoteEP);
            Console.WriteLine("Client connected to {0}.", remoteEP.ToString());
            // Ensure the client does not close when there is
            // still data to be sent to the server.
            client.LingerState = new LingerOption(true, 0);
            // Request authentication.
            NetworkStream clientStream = client.GetStream();
            NegotiateStream authStream = new NegotiateStream(clientStream, false);
            // Pass the NegotiateStream as the AsyncState object
            // so that it is available to the callback delegate.
            Task authenticateTask = authStream
                .AuthenticateAsClientAsync()
                .ContinueWith(task =>
                {
                    Console.WriteLine("Client ending authentication...");
                    Console.WriteLine("ImpersonationLevel: {0}", authStream.ImpersonationLevel);
                });

            Console.WriteLine("Client waiting for authentication...");
            // Wait until the result is available.
            authenticateTask.Wait();
            // Display the properties of the authenticated stream.
            AuthenticatedStreamReporter.DisplayProperties(authStream);
            // Send a message to the server.
            // Encode the test data into a byte array.
            byte[] message = Encoding.UTF8.GetBytes("Hello from the client.");
            Task writeTask = authStream
                .WriteAsync(message, 0, message.Length)
                .ContinueWith(task =>
                {
                    Console.WriteLine("Client ending write operation...");
                });

            writeTask.Wait();
            Console.WriteLine("Sent {0} bytes.", message.Length);
            // Close the client connection.
            authStream.Close();
            Console.WriteLine("Client closed.");
        }
    }

    // The following class displays the properties of an authenticatedStream.
    public class AuthenticatedStreamReporter
    {
        public static void DisplayProperties(AuthenticatedStream stream)
        {
            Console.WriteLine("IsAuthenticated: {0}", stream.IsAuthenticated);
            Console.WriteLine("IsMutuallyAuthenticated: {0}", stream.IsMutuallyAuthenticated);
            Console.WriteLine("IsEncrypted: {0}", stream.IsEncrypted);
            Console.WriteLine("IsSigned: {0}", stream.IsSigned);
            Console.WriteLine("IsServer: {0}", stream.IsServer);
        }
    }
}

Imports System.Text
Imports System.Net.Sockets
Imports System.Net.Security
Imports System.Net

Namespace Examples.NegotiateStreamExample

    Public Class ASynchronousAuthenticatingTcpClient

        Shared client As TcpClient = Nothing

        Public Shared Sub Main(args As String())
            ' Establish the remote endpoint for the socket.
            ' For this example, use the local machine.
            Dim ipHostInfo = Dns.GetHostEntry("localhost")
            Dim ipAddress = ipHostInfo.AddressList(0)

            ' Client and server use port 11000. 
            Dim remoteEP As New IPEndPoint(ipAddress, 11000)

            ' Create a TCP/IP socket.
            client = New TcpClient()

            ' Connect the socket to the remote endpoint.
            client.Connect(remoteEP)
            Console.WriteLine("Client connected to {0}.", remoteEP.ToString())

            ' Ensure the client does not close when there is 
            ' still data to be sent to the server.
            client.LingerState = (New LingerOption(True, 0))

            ' Request authentication.
            Dim clientStream = client.GetStream()
            Dim authStream As New NegotiateStream(clientStream, False)

            ' Pass the NegotiateStream as the AsyncState object 
            ' so that it is available to the callback delegate.
            Dim ar = authStream.BeginAuthenticateAsClient(
                New AsyncCallback(AddressOf EndAuthenticateCallback), authStream)

            Console.WriteLine("Client waiting for authentication...")

            ' Wait until the result is available.
            ar.AsyncWaitHandle.WaitOne()

            ' Display the properties of the authenticated stream.
            AuthenticatedStreamReporter.DisplayProperties(authStream)

            ' Send a message to the server.
            ' Encode the test data into a byte array.
            Dim message = Encoding.UTF8.GetBytes("Hello from the client.")
            ar = authStream.BeginWrite(message, 0, message.Length, 
                New AsyncCallback(AddressOf EndWriteCallback), authStream)
            ar.AsyncWaitHandle.WaitOne()
            Console.WriteLine("Sent {0} bytes.", message.Length)

            ' Close the client connection.
            authStream.Close()
            Console.WriteLine("Client closed.")

        End Sub

        ' The following method is called when the authentication completes.
        Public Shared Sub EndAuthenticateCallback(ar As IAsyncResult)

            Console.WriteLine("Client ending authentication...")
            Dim authStream = CType(ar.AsyncState, NegotiateStream)
            Console.WriteLine("ImpersonationLevel: {0}", authStream.ImpersonationLevel)

            ' End the asynchronous operation.
            authStream.EndAuthenticateAsClient(ar)

        End Sub

        ' The following method is called when the write operation completes.
        Public Shared Sub EndWriteCallback(ar As IAsyncResult)

            Console.WriteLine("Client ending write operation...")
            Dim authStream = CType(ar.AsyncState, NegotiateStream)

            ' End the asynchronous operation.
            authStream.EndWrite(ar)

        End Sub
    End Class

    ' The following class displays the properties of an AuthenticatedStream.
    Public Class AuthenticatedStreamReporter
        Public Shared Sub DisplayProperties(stream As AuthenticatedStream)
            Console.WriteLine("IsAuthenticated: {0}", stream.IsAuthenticated)
            Console.WriteLine("IsMutuallyAuthenticated: {0}", stream.IsMutuallyAuthenticated)
            Console.WriteLine("IsEncrypted: {0}", stream.IsEncrypted)
            Console.WriteLine("IsSigned: {0}", stream.IsSigned)
            Console.WriteLine("IsServer: {0}", stream.IsServer)
        End Sub
    End Class
End Namespace

In het volgende codevoorbeeld ziet u de serverzijde van een client-serververbinding die gebruikmaakt van de NegotiateStream client om de client te verifiëren en een bericht te lezen dat door de client wordt verzonden.

using System;
using System.Net;
using System.Net.Security;
using System.Net.Sockets;
using System.Security.Authentication;
using System.Security.Principal;
using System.Text;
using System.IO;
using System.Threading;

namespace Examples.NegotiateStreamExample
{
    public class AsynchronousAuthenticatingTcpListener
    {
        public static void Main()
        {
            // Create an IPv4 TCP/IP socket.
            TcpListener listener = new TcpListener(IPAddress.Any, 11000);
            // Listen for incoming connections.
            listener.Start();
            while (true)
            {
                TcpClient clientRequest;
                // Application blocks while waiting for an incoming connection.
                // Type CNTL-C to terminate the server.
                clientRequest = listener.AcceptTcpClient();
                Console.WriteLine("Client connected.");
                // A client has connected.
                try
                {
                    AuthenticateClient(clientRequest);
                }
                catch (Exception e)
                {
                    Console.WriteLine(e);
                }
            }
        }

        public static void AuthenticateClient(TcpClient clientRequest)
        {
            NetworkStream stream = clientRequest.GetStream();
            // Create the NegotiateStream.
            NegotiateStream authStream = new NegotiateStream(stream, false);
            // Save the current client and NegotiateStream instance
            // in a ClientState object.
            ClientState cState = new ClientState(authStream, clientRequest);
            // Listen for the client authentication request.
            Task authTask = authStream
                .AuthenticateAsServerAsync()
                .ContinueWith(task => { EndAuthenticateCallback(cState); });

            // Any exceptions that occurred during authentication are
            // thrown by the EndAuthenticateAsServer method.
            try
            {
                // This call blocks until the authentication is complete.
                authTask.Wait();
            }
            catch (AuthenticationException e)
            {
                Console.WriteLine(e);
                Console.WriteLine("Authentication failed - closing connection.");
                return;
            }
            catch (Exception e)
            {
                Console.WriteLine(e);
                Console.WriteLine("Closing connection.");
                return;
            }

            Task<int> readTask = authStream
                .ReadAsync(cState.Buffer, 0, cState.Buffer.Length);

            readTask
                .ContinueWith((task) => { EndReadCallback(cState, task.Result); })
                .Wait();
            // Finished with the current client.
            authStream.Close();
            clientRequest.Close();
        }

        private static void EndAuthenticateCallback(ClientState cState)
        {
            // Get the saved data.
            NegotiateStream authStream = (NegotiateStream)cState.AuthenticatedStream;
            Console.WriteLine("Ending authentication.");

            // Display properties of the authenticated client.
            IIdentity id = authStream.RemoteIdentity;
            Console.WriteLine("{0} was authenticated using {1}.",
                id.Name,
                id.AuthenticationType
            );
        }

        private static void EndReadCallback(ClientState cState, int bytes)
        {
            NegotiateStream authStream = (NegotiateStream)cState.AuthenticatedStream;
            // Read the client message.
            try
            {
                cState.Message.Append(Encoding.UTF8.GetChars(cState.Buffer, 0, bytes));
                if (bytes != 0)
                {
                    Task<int> readTask = authStream.ReadAsync(cState.Buffer, 0, cState.Buffer.Length);
                    readTask
                        .ContinueWith(task => { EndReadCallback(cState, task.Result); })
                        .Wait();

                    return;
                }
            }
            catch (Exception e)
            {
                // A real application should do something
                // useful here, such as logging the failure.
                Console.WriteLine("Client message exception:");
                Console.WriteLine(e);
                return;
            }
            IIdentity id = authStream.RemoteIdentity;
            Console.WriteLine("{0} says {1}", id.Name, cState.Message.ToString());
        }
    }
    // ClientState is the AsyncState object.
    internal class ClientState
    {
        private StringBuilder _message = null;

        internal ClientState(AuthenticatedStream a, TcpClient theClient)
        {
            AuthenticatedStream = a;
            Client = theClient;
        }
        internal TcpClient Client { get; }

        internal AuthenticatedStream AuthenticatedStream { get; }

        internal byte[] Buffer { get; } = new byte[2048];

        internal StringBuilder Message
        {
            get { return _message ??= new StringBuilder(); }
        }
    }
}

Opmerkingen

Gebruik de NegotiateStream klasse voor verificatie en om gegevens te beveiligen die worden verzonden tussen een client en een server. Met behulp van NegotiateStream, kunt u het volgende doen.

• Verzend de referenties van de client naar de server voor imitatie of delegering.
• Serververificatie aanvragen.
• Gegevens versleutelen en/of ondertekenen voordat ze worden verzonden.

Verificatie moet worden uitgevoerd voordat gegevens worden verzonden. Clients vragen verificatie aan met behulp van de synchrone AuthenticateAsClient methoden, die blokkeren totdat de verificatie is voltooid, of de asynchrone BeginAuthenticateAsClient methoden, die niet worden geblokkeerd terwijl wordt gewacht totdat de verificatie is voltooid. Servers vragen verificatie aan met behulp van de synchrone AuthenticateAsServer of asynchrone BeginAuthenticateAsServer methoden. De client en eventueel de server worden geverifieerd met behulp van het protocol Negotiate Security. Het Kerberos-protocol wordt gebruikt voor verificatie als zowel de client als de server dit ondersteunen; anders wordt NTLM gebruikt. De NegotiateStream klasse voert de verificatie uit met behulp van de SSPI (Security Support Provider Interface).

Wanneer de verificatie is geslaagd, moet u de IsEncrypted en IsSigned eigenschappen controleren om te bepalen welke beveiligingsservices worden gebruikt door de NegotiateStream beveiligingsservices om uw gegevens tijdens de overdracht te beveiligen. Controleer de IsMutuallyAuthenticated eigenschap om te bepalen of er wederzijdse verificatie is opgetreden. U kunt informatie over de externe client of server ophalen met behulp van de RemoteIdentity eigenschap.

Als de verificatie mislukt, ontvangt u een AuthenticationException of een InvalidCredentialException. In dit geval kunt u de verificatie opnieuw proberen met een andere referentie.

U verzendt gegevens met behulp van de synchrone Write of asynchrone BeginWrite methoden WriteAsync . U ontvangt gegevens met behulp van de synchrone Read of asynchrone ReadAsync methoden BeginRead . Als beveiligingsservices zoals versleuteling of ondertekening zijn ingeschakeld, worden deze automatisch toegepast op uw gegevens door de NegotiateStream.

De NegotiateStream gegevens worden verzonden met behulp van een stroom die u opgeeft bij het maken van de NegotiateStream. Wanneer u deze onderliggende stroom opgeeft, kunt u opgeven of de NegotiateStream onderliggende stroom ook wordt gesloten.

Zie ook

• Wijzigingen in NTLM-verificatie voor HTTPWebRequest in versie 3.5 SP1