作法：使用具名管道進行網路處理序間通訊

發行項
03/13/2024

具名管道可在管道伺服器及一個或多個管道用戶端之間提供處理序間通訊。它們比在本機電腦上處理流程間通訊的匿名管道提供更多的功能。具名管道支援在網路及多個伺服器執行個體上進行全雙工通訊、訊息架構通訊及用戶端模擬。用戶端模擬可讓連接處理序在遠端伺服器上使用本身的權限集合。

重要

Linux 上的 .NET 會使用 Unix 網域通訊端 (UDS) 來實作這些 API。

若要實作具名管道，請使用 NamedPipeServerStream 和 NamedPipeClientStream 類別。

範例 1

下列範例示範如何使用 NamedPipeServerStream 類別建立具名管道。在此範例中，伺服器處理序會建立四個執行緒。每個執行緒都可以接受用戶端連線。接著，連線的用戶端處理序會提供具有檔案名稱的伺服器。如果用戶端有足夠的權限，伺服器處理序就會開啟檔案，並將其內容傳回用戶端。

#using <System.Core.dll>

using namespace System;
using namespace System::IO;
using namespace System::IO::Pipes;
using namespace System::Text;
using namespace System::Threading;

// Defines the data protocol for reading and writing strings on our stream
public ref class StreamString
{
private:
    Stream^ ioStream;
    UnicodeEncoding^ streamEncoding;

public:
    StreamString(Stream^ ioStream)
    {
        this->ioStream = ioStream;
        streamEncoding = gcnew UnicodeEncoding();
    }

    String^ ReadString()
    {
        int len;

        len = ioStream->ReadByte() * 256;
        len += ioStream->ReadByte();
        array<Byte>^ inBuffer = gcnew array<Byte>(len);
        ioStream->Read(inBuffer, 0, len);

        return streamEncoding->GetString(inBuffer);
    }

    int WriteString(String^ outString)
    {
        array<Byte>^ outBuffer = streamEncoding->GetBytes(outString);
        int len = outBuffer->Length;
        if (len > UInt16::MaxValue)
        {
            len = (int)UInt16::MaxValue;
        }
        ioStream->WriteByte((Byte)(len / 256));
        ioStream->WriteByte((Byte)(len & 255));
        ioStream->Write(outBuffer, 0, len);
        ioStream->Flush();

        return outBuffer->Length + 2;
    }
};

// Contains the method executed in the context of the impersonated user
public ref class ReadFileToStream
{
private:
    String^ fn;
    StreamString ^ss;

public:
    ReadFileToStream(StreamString^ str, String^ filename)
    {
        fn = filename;
        ss = str;
    }

    void Start()
    {
        String^ contents = File::ReadAllText(fn);
        ss->WriteString(contents);
    }
};

public ref class PipeServer
{
private:
    static int numThreads = 4;

public:
    static void Main()
    {
        int i;
        array<Thread^>^ servers = gcnew array<Thread^>(numThreads);

        Console::WriteLine("\n*** Named pipe server stream with impersonation example ***\n");
        Console::WriteLine("Waiting for client connect...\n");
        for (i = 0; i < numThreads; i++)
        {
            servers[i] = gcnew Thread(gcnew ThreadStart(&ServerThread));
            servers[i]->Start();
        }
        Thread::Sleep(250);
        while (i > 0)
        {
            for (int j = 0; j < numThreads; j++)
            {
                if (servers[j] != nullptr)
                {
                    if (servers[j]->Join(250))
                    {
                        Console::WriteLine("Server thread[{0}] finished.", servers[j]->ManagedThreadId);
                        servers[j] = nullptr;
                        i--;    // decrement the thread watch count
                    }
                }
            }
        }
        Console::WriteLine("\nServer threads exhausted, exiting.");
    }

private:
    static void ServerThread()
    {
        NamedPipeServerStream^ pipeServer =
            gcnew NamedPipeServerStream("testpipe", PipeDirection::InOut, numThreads);

        int threadId = Thread::CurrentThread->ManagedThreadId;

        // Wait for a client to connect
        pipeServer->WaitForConnection();

        Console::WriteLine("Client connected on thread[{0}].", threadId);
        try
        {
            // Read the request from the client. Once the client has
            // written to the pipe its security token will be available.

            StreamString^ ss = gcnew StreamString(pipeServer);

            // Verify our identity to the connected client using a
            // string that the client anticipates.

            ss->WriteString("I am the one true server!");
            String^ filename = ss->ReadString();

            // Read in the contents of the file while impersonating the client.
            ReadFileToStream^ fileReader = gcnew ReadFileToStream(ss, filename);

            // Display the name of the user we are impersonating.
            Console::WriteLine("Reading file: {0} on thread[{1}] as user: {2}.",
                filename, threadId, pipeServer->GetImpersonationUserName());
            pipeServer->RunAsClient(gcnew PipeStreamImpersonationWorker(fileReader, &ReadFileToStream::Start));
        }
        // Catch the IOException that is raised if the pipe is broken
        // or disconnected.
        catch (IOException^ e)
        {
            Console::WriteLine("ERROR: {0}", e->Message);
        }
        pipeServer->Close();
    }
};

int main()
{
    PipeServer::Main();
}

using System;
using System.IO;
using System.IO.Pipes;
using System.Text;
using System.Threading;

public class PipeServer
{
    private static int numThreads = 4;

    public static void Main()
    {
        int i;
        Thread?[] servers = new Thread[numThreads];

        Console.WriteLine("\n*** Named pipe server stream with impersonation example ***\n");
        Console.WriteLine("Waiting for client connect...\n");
        for (i = 0; i < numThreads; i++)
        {
            servers[i] = new Thread(ServerThread);
            servers[i]?.Start();
        }
        Thread.Sleep(250);
        while (i > 0)
        {
            for (int j = 0; j < numThreads; j++)
            {
                if (servers[j] != null)
                {
                    if (servers[j]!.Join(250))
                    {
                        Console.WriteLine("Server thread[{0}] finished.", servers[j]!.ManagedThreadId);
                        servers[j] = null;
                        i--;    // decrement the thread watch count
                    }
                }
            }
        }
        Console.WriteLine("\nServer threads exhausted, exiting.");
    }

    private static void ServerThread(object? data)
    {
        NamedPipeServerStream pipeServer =
            new NamedPipeServerStream("testpipe", PipeDirection.InOut, numThreads);

        int threadId = Thread.CurrentThread.ManagedThreadId;

        // Wait for a client to connect
        pipeServer.WaitForConnection();

        Console.WriteLine("Client connected on thread[{0}].", threadId);
        try
        {
            // Read the request from the client. Once the client has
            // written to the pipe its security token will be available.

            StreamString ss = new StreamString(pipeServer);

            // Verify our identity to the connected client using a
            // string that the client anticipates.

            ss.WriteString("I am the one true server!");
            string filename = ss.ReadString();

            // Read in the contents of the file while impersonating the client.
            ReadFileToStream fileReader = new ReadFileToStream(ss, filename);

            // Display the name of the user we are impersonating.
            Console.WriteLine("Reading file: {0} on thread[{1}] as user: {2}.",
                filename, threadId, pipeServer.GetImpersonationUserName());
            pipeServer.RunAsClient(fileReader.Start);
        }
        // Catch the IOException that is raised if the pipe is broken
        // or disconnected.
        catch (IOException e)
        {
            Console.WriteLine("ERROR: {0}", e.Message);
        }
        pipeServer.Close();
    }
}

// Defines the data protocol for reading and writing strings on our stream
public class StreamString
{
    private Stream ioStream;
    private UnicodeEncoding streamEncoding;

    public StreamString(Stream ioStream)
    {
        this.ioStream = ioStream;
        streamEncoding = new UnicodeEncoding();
    }

    public string ReadString()
    {
        int len = 0;

        len = ioStream.ReadByte() * 256;
        len += ioStream.ReadByte();
        byte[] inBuffer = new byte[len];
        ioStream.Read(inBuffer, 0, len);

        return streamEncoding.GetString(inBuffer);
    }

    public int WriteString(string outString)
    {
        byte[] outBuffer = streamEncoding.GetBytes(outString);
        int len = outBuffer.Length;
        if (len > UInt16.MaxValue)
        {
            len = (int)UInt16.MaxValue;
        }
        ioStream.WriteByte((byte)(len / 256));
        ioStream.WriteByte((byte)(len & 255));
        ioStream.Write(outBuffer, 0, len);
        ioStream.Flush();

        return outBuffer.Length + 2;
    }
}

// Contains the method executed in the context of the impersonated user
public class ReadFileToStream
{
    private string fn;
    private StreamString ss;

    public ReadFileToStream(StreamString str, string filename)
    {
        fn = filename;
        ss = str;
    }

    public void Start()
    {
        string contents = File.ReadAllText(fn);
        ss.WriteString(contents);
    }
}

Imports System.IO
Imports System.IO.Pipes
Imports System.Text
Imports System.Threading

Public Class PipeServer
    Private Shared numThreads As Integer = 4

    Public Shared Sub Main()
        Dim i As Integer
        Dim servers(numThreads) As Thread

        Console.WriteLine(vbCrLf + "*** Named pipe server stream with impersonation example ***" + vbCrLf)
        Console.WriteLine("Waiting for client connect..." + vbCrLf)
        For i = 0 To numThreads - 1
            servers(i) = New Thread(AddressOf ServerThread)
            servers(i).Start()
        Next i
        Thread.Sleep(250)
        While i > 0
            For j As Integer = 0 To numThreads - 1
                If Not (servers(j) Is Nothing) Then
                    If servers(j).Join(250) Then
                        Console.WriteLine("Server thread[{0}] finished.", servers(j).ManagedThreadId)
                        servers(j) = Nothing
                        i -= 1    ' decrement the thread watch count
                    End If
                End If
            Next j
        End While
        Console.WriteLine(vbCrLf + "Server threads exhausted, exiting.")
    End Sub

    Private Shared Sub ServerThread(data As Object)
        Dim pipeServer As New _
            NamedPipeServerStream("testpipe", PipeDirection.InOut, numThreads)

        Dim threadId As Integer = Thread.CurrentThread.ManagedThreadId

        ' Wait for a client to connect
        pipeServer.WaitForConnection()

        Console.WriteLine("Client connected on thread[{0}].", threadId)
        Try
            ' Read the request from the client. Once the client has
            ' written to the pipe its security token will be available.

            Dim ss As new StreamString(pipeServer)

            ' Verify our identity to the connected client using a
            ' string that the client anticipates.

            ss.WriteString("I am the one true server!")
            Dim filename As String = ss.ReadString()

            ' Read in the contents of the file while impersonating the client.
            Dim fileReader As New ReadFileToStream(ss, filename)

            ' Display the name of the user we are impersonating.
            Console.WriteLine("Reading file: {0} on thread[{1}] as user: {2}.",
                filename, threadId, pipeServer.GetImpersonationUserName())
            pipeServer.RunAsClient(AddressOf fileReader.Start)
            ' Catch the IOException that is raised if the pipe is broken
            ' or disconnected.
        Catch e As IOException
            Console.WriteLine("ERROR: {0}", e.Message)
        End Try
        pipeServer.Close()
    End Sub
End Class

' Defines the data protocol for reading and writing strings on our stream
Public Class StreamString
    Private ioStream As Stream
    Private streamEncoding As UnicodeEncoding

    Public Sub New(ioStream As Stream)
        Me.ioStream = ioStream
        streamEncoding = New UnicodeEncoding(False, False)
    End Sub

    Public Function ReadString() As String
        Dim len As Integer = 0
        len = CType(ioStream.ReadByte(), Integer) * 256
        len += CType(ioStream.ReadByte(), Integer)
        Dim inBuffer As Array = Array.CreateInstance(GetType(Byte), len)
        ioStream.Read(inBuffer, 0, len)

        Return streamEncoding.GetString(CType(inBuffer, Byte()))
    End Function

    Public Function WriteString(outString As String) As Integer
        Dim outBuffer() As Byte = streamEncoding.GetBytes(outString)
        Dim len As Integer = outBuffer.Length
        If len > UInt16.MaxValue Then
            len = CType(UInt16.MaxValue, Integer)
        End If
        ioStream.WriteByte(CType(len \ 256, Byte))
        ioStream.WriteByte(CType(len And 255, Byte))
        ioStream.Write(outBuffer, 0, outBuffer.Length)
        ioStream.Flush()

        Return outBuffer.Length + 2
    End Function
End Class

' Contains the method executed in the context of the impersonated user
Public Class ReadFileToStream
    Private fn As String
    Private ss As StreamString

    Public Sub New(str As StreamString, filename As String)
        fn = filename
        ss = str
    End Sub

    Public Sub Start()
        Dim contents As String = File.ReadAllText(fn)
        ss.WriteString(contents)
    End Sub
End Class

範例 2

下列範例示範使用 NamedPipeClientStream 類別的用戶端處理序。用戶端會連線至伺服器處理序，並將檔案名稱傳送至伺服器。此範例會使用模擬，因此，執行用戶端應用程式的身分識別必須擁有存取該檔案的權限。接著，伺服器會將檔案的內容傳回用戶端。檔案內容隨即顯示到主控台。

using System;
using System.Diagnostics;
using System.IO;
using System.IO.Pipes;
using System.Security.Principal;
using System.Text;
using System.Threading;

public class PipeClient
{
    private static int numClients = 4;

    public static void Main(string[] args)
    {
        if (args.Length > 0)
        {
            if (args[0] == "spawnclient")
            {
                var pipeClient =
                    new NamedPipeClientStream(".", "testpipe",
                        PipeDirection.InOut, PipeOptions.None,
                        TokenImpersonationLevel.Impersonation);

                Console.WriteLine("Connecting to server...\n");
                pipeClient.Connect();

                var ss = new StreamString(pipeClient);
                // Validate the server's signature string.
                if (ss.ReadString() == "I am the one true server!")
                {
                    // The client security token is sent with the first write.
                    // Send the name of the file whose contents are returned
                    // by the server.
                    ss.WriteString("c:\\textfile.txt");

                    // Print the file to the screen.
                    Console.Write(ss.ReadString());
                }
                else
                {
                    Console.WriteLine("Server could not be verified.");
                }
                pipeClient.Close();
                // Give the client process some time to display results before exiting.
                Thread.Sleep(4000);
            }
        }
        else
        {
            Console.WriteLine("\n*** Named pipe client stream with impersonation example ***\n");
            StartClients();
        }
    }

    // Helper function to create pipe client processes
    private static void StartClients()
    {
        string currentProcessName = Environment.CommandLine;

        // Remove extra characters when launched from Visual Studio
        currentProcessName = currentProcessName.Trim('"', ' ');

        currentProcessName = Path.ChangeExtension(currentProcessName, ".exe");
        Process?[] plist = new Process?[numClients];

        Console.WriteLine("Spawning client processes...\n");

        if (currentProcessName.Contains(Environment.CurrentDirectory))
        {
            currentProcessName = currentProcessName.Replace(Environment.CurrentDirectory, String.Empty);
        }

        // Remove extra characters when launched from Visual Studio
        currentProcessName = currentProcessName.Replace("\\", String.Empty);
        currentProcessName = currentProcessName.Replace("\"", String.Empty);

        int i;
        for (i = 0; i < numClients; i++)
        {
            // Start 'this' program but spawn a named pipe client.
            plist[i] = Process.Start(currentProcessName, "spawnclient");
        }
        while (i > 0)
        {
            for (int j = 0; j < numClients; j++)
            {
                if (plist[j] != null)
                {
                    if (plist[j]!.HasExited)
                    {
                        Console.WriteLine($"Client process[{plist[j]?.Id}] has exited.");
                        plist[j] = null;
                        i--;    // decrement the process watch count
                    }
                    else
                    {
                        Thread.Sleep(250);
                    }
                }
            }
        }
        Console.WriteLine("\nClient processes finished, exiting.");
    }
}

// Defines the data protocol for reading and writing strings on our stream.
public class StreamString
{
    private Stream ioStream;
    private UnicodeEncoding streamEncoding;

    public StreamString(Stream ioStream)
    {
        this.ioStream = ioStream;
        streamEncoding = new UnicodeEncoding();
    }

    public string ReadString()
    {
        int len;
        len = ioStream.ReadByte() * 256;
        len += ioStream.ReadByte();
        var inBuffer = new byte[len];
        ioStream.Read(inBuffer, 0, len);

        return streamEncoding.GetString(inBuffer);
    }

    public int WriteString(string outString)
    {
        byte[] outBuffer = streamEncoding.GetBytes(outString);
        int len = outBuffer.Length;
        if (len > UInt16.MaxValue)
        {
            len = (int)UInt16.MaxValue;
        }
        ioStream.WriteByte((byte)(len / 256));
        ioStream.WriteByte((byte)(len & 255));
        ioStream.Write(outBuffer, 0, len);
        ioStream.Flush();

        return outBuffer.Length + 2;
    }
}

Imports System.Diagnostics
Imports System.IO
Imports System.IO.Pipes
Imports System.Security.Principal
Imports System.Text
Imports System.Threading

Public Class PipeClient
    Private Shared numClients As Integer = 4

    Public Shared Sub Main(args() As String)
        If args.Length > 0 Then
            If args(0) = "spawnclient" Then
                Dim pipeClient As New NamedPipeClientStream( _
                    ".", "testpipe", _
                    PipeDirection.InOut, PipeOptions.None, _
                    TokenImpersonationLevel.Impersonation)

                Console.WriteLine("Connecting to server..." + vbCrLf)
                pipeClient.Connect()

                Dim ss As New StreamString(pipeClient)
                ' Validate the server's signature string.
                If ss.ReadString() = "I am the one true server!" Then
                    ' The client security token is sent with the first write.
                    ' Send the name of the file whose contents are returned
                    ' by the server.
                    ss.WriteString("c:\textfile.txt")

                    ' Print the file to the screen.
                    Console.Write(ss.ReadString())
                Else
                    Console.WriteLine("Server could not be verified.")
                End If
                pipeClient.Close()
                ' Give the client process some time to display results before exiting.
                Thread.Sleep(4000)
            End If
        Else
            Console.WriteLine(vbCrLf + "*** Named pipe client stream with impersonation example ***" + vbCrLf)
            StartClients()
        End If
    End Sub

    ' Helper function to create pipe client processes
    Private Shared Sub StartClients()
        Dim currentProcessName As String = Environment.CommandLine
        Dim plist(numClients - 1) As Process

        Console.WriteLine("Spawning client processes..." + vbCrLf)

        If currentProcessName.Contains(Environment.CurrentDirectory) Then
            currentProcessName = currentProcessName.Replace(Environment.CurrentDirectory, String.Empty)
        End If

        ' Remove extra characters when launched from Visual Studio.
        currentProcessName = currentProcessName.Replace("\", String.Empty)
        currentProcessName = currentProcessName.Replace("""", String.Empty)

        ' Change extension for .NET Core "dotnet run" returns the DLL, not the host exe.
        currentProcessName = Path.ChangeExtension(currentProcessName, ".exe")

        Dim i As Integer
        For i = 0 To numClients - 1
            ' Start 'this' program but spawn a named pipe client.
            plist(i) = Process.Start(currentProcessName, "spawnclient")
        Next
        While i > 0
            For j As Integer = 0 To numClients - 1
                If plist(j) IsNot Nothing Then
                    If plist(j).HasExited Then
                        Console.WriteLine($"Client process[{plist(j).Id}] has exited.")
                        plist(j) = Nothing
                        i -= 1    ' decrement the process watch count
                    Else
                        Thread.Sleep(250)
                    End If
                End If
            Next
        End While
        Console.WriteLine(vbCrLf + "Client processes finished, exiting.")
    End Sub
End Class

' Defines the data protocol for reading and writing strings on our stream
Public Class StreamString
    Private ioStream As Stream
    Private streamEncoding As UnicodeEncoding

    Public Sub New(ioStream As Stream)
        Me.ioStream = ioStream
        streamEncoding = New UnicodeEncoding(False, False)
    End Sub

    Public Function ReadString() As String
        Dim len As Integer = 0
        len = CType(ioStream.ReadByte(), Integer) * 256
        len += CType(ioStream.ReadByte(), Integer)
        Dim inBuffer As Array = Array.CreateInstance(GetType(Byte), len)
        ioStream.Read(inBuffer, 0, len)

        Return streamEncoding.GetString(CType(inBuffer, Byte()))
    End Function

    Public Function WriteString(outString As String) As Integer
        Dim outBuffer As Byte() = streamEncoding.GetBytes(outString)
        Dim len As Integer = outBuffer.Length
        If len > UInt16.MaxValue Then
            len = CType(UInt16.MaxValue, Integer)
        End If
        ioStream.WriteByte(CType(len \ 256, Byte))
        ioStream.WriteByte(CType(len And 255, Byte))
        ioStream.Write(outBuffer, 0, outBuffer.Length)
        ioStream.Flush()

        Return outBuffer.Length + 2
    End Function
End Class

穩固程式設計

此範例中的用戶端和伺服器處理序要在相同的電腦上執行，因此，提供給 NamedPipeClientStream 物件的伺服器名稱為 "."。如果用戶端和伺服器處理序在不同的電腦上，"." 將會取代成執行伺服器處理序之電腦的網路名稱。

共用方式為

作法：使用具名管道進行網路處理序間通訊

範例 1

範例 2

穩固程式設計

另請參閱

其他資源