如何在 C# 中连接到 .NET Core 中的 Unix 域套接字
本文关键字:中的 Core Unix 套接字 NET 连接 | 更新日期: 2023-09-27 18:14:16
我在Linux(Ubuntu 16.04(上的.NET Core中创建了一个unix套接字:
var unixSocket = "/var/run/mysqld/mysqld.sock";
var socket = new Socket(AddressFamily.Unix, SocketType.Stream, ProtocolType.IP);
现在如何连接插座?
.NET Core API列出了各种Socket.Connect选项,但除了第一个选项外,所有选项都涉及IP地址:
public void Connect(EndPoint remoteEP)
public void Connect(IPAddress address, int port)
public void Connect(IPAddress[] addresses, int port)
public void Connect(string host, int port)
System.Net API 定义了DNSEndpoint
和IPEndpoint
,但我似乎找不到要传递给UnixEndpoint
或类似的类Socket.Connect(EndPoint remoteEP)
更新:.NET Standard 2.1/.NET Core 2.1 包含一个 UnixDomainSocketEndPoint 类
原始答案,适用于 2.1 之前的 .NET Standard/.NET Core 版本:
在撰写本文时,似乎没有用于 .NET Core 的内置 UnixEndPoint
类或实现该类的库。 来自Mono.Posix项目的UnixEndPoint类可以很容易地适应.NET Core,但是:
// copied from https://github.com/mono/mono/blob/master/mcs/class/Mono.Posix/Mono.Unix/UnixEndPoint.cs
//
// Mono.Unix.UnixEndPoint: EndPoint derived class for AF_UNIX family sockets.
//
// Authors:
// Gonzalo Paniagua Javier (gonzalo@ximian.com)
//
// (C) 2003 Ximian, Inc (http://www.ximian.com)
//
//
// Permission is hereby granted, free of charge, to any person obtaining
// a copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to
// permit persons to whom the Software is furnished to do so, subject to
// the following conditions:
//
// The above copyright notice and this permission notice shall be
// included in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//
using System.Net.Sockets;
using System.Text;
namespace System.Net
{
public class UnixEndPoint : EndPoint
{
string filename;
public UnixEndPoint (string filename)
{
if (filename == null)
throw new ArgumentNullException ("filename");
if (filename == "")
throw new ArgumentException ("Cannot be empty.", "filename");
this.filename = filename;
}
public string Filename {
get {
return(filename);
}
set {
filename=value;
}
}
public override AddressFamily AddressFamily {
get { return AddressFamily.Unix; }
}
public override EndPoint Create (SocketAddress socketAddress)
{
/*
* Should also check this
*
int addr = (int) AddressFamily.Unix;
if (socketAddress [0] != (addr & 0xFF))
throw new ArgumentException ("socketAddress is not a unix socket address.");
if (socketAddress [1] != ((addr & 0xFF00) >> 8))
throw new ArgumentException ("socketAddress is not a unix socket address.");
*/
if (socketAddress.Size == 2) {
// Empty filename.
// Probably from RemoteEndPoint which on linux does not return the file name.
UnixEndPoint uep = new UnixEndPoint ("a");
uep.filename = "";
return uep;
}
int size = socketAddress.Size - 2;
byte [] bytes = new byte [size];
for (int i = 0; i < bytes.Length; i++) {
bytes [i] = socketAddress [i + 2];
// There may be junk after the null terminator, so ignore it all.
if (bytes [i] == 0) {
size = i;
break;
}
}
string name = Encoding.UTF8.GetString (bytes, 0, size);
return new UnixEndPoint (name);
}
public override SocketAddress Serialize ()
{
byte [] bytes = Encoding.UTF8.GetBytes (filename);
SocketAddress sa = new SocketAddress (AddressFamily, 2 + bytes.Length + 1);
// sa [0] -> family low byte, sa [1] -> family high byte
for (int i = 0; i < bytes.Length; i++)
sa [2 + i] = bytes [i];
//NULL suffix for non-abstract path
sa[2 + bytes.Length] = 0;
return sa;
}
public override string ToString() {
return(filename);
}
public override int GetHashCode ()
{
return filename.GetHashCode ();
}
public override bool Equals (object o)
{
UnixEndPoint other = o as UnixEndPoint;
if (other == null)
return false;
return (other.filename == filename);
}
}
}
在项目中使用此类,套接字可以像这样连接:
var unixSocket = "/var/run/mysqld/mysqld.sock";
var socket = new Socket(AddressFamily.Unix, SocketType.Stream, ProtocolType.IP);
var unixEp = new UnixEndPoint(unixSocket);
socket.Connect(unixEp);
using System.Net.Sockets;
var unixSocketName = "/var/run/mysqld/mysqld.sock";
var unixSocket = new Socket(AddressFamily.Unix, SocketType.Stream, ProtocolType.IP);
unixSocket.Connect(new UnixDomainSocketEndPoint(unixSocketName));
因为我找不到一个很好的Unix套接字的例子,所以我设计了自己的套接字。它非常粗鲁,没有太多的错误捕获,但它有效。
在这里:
using System;
using System.Net.Sockets;
using System.Threading;
namespace mps.unix.socket
{
public class UnixSocket
{
private Socket recvSocket;
private string unixSocketpath; // needed for cleanup
private bool running = true;
private byte[] data = new byte[0];
public UnixSocket(string unixSocket)
{
this.unixSocketpath = unixSocket;
this.recvSocket = new Socket(AddressFamily.Unix, SocketType.Stream, ProtocolType.Unspecified);
System.IO.File.Delete(unixSocketpath);
var ep = new UnixDomainSocketEndPoint(unixSocketpath);
recvSocket.Bind(ep);
recvSocket.Listen();
Thread w = new Thread(worker);
w.Start();
}
private void worker()
{
while (this.running)
{
try
{
var clientSocket = this.recvSocket.Accept(); // waits for 'client' to 'connect'
Thread t = new Thread(delegate () { clientWorker(clientSocket); });
t.Start();
}
catch (Exception) { }
}
}
private void clientWorker(Socket s)
{
while (running)
{
byte[] d = new byte[s.ReceiveBufferSize];
int length = s.Receive(d);
lock (this.data)
{
byte[] newData = new byte[this.data.Length + length];
Buffer.BlockCopy(this.data, 0, newData, 0, this.data.Length);
Buffer.BlockCopy(d, 0, newData, this.data.Length, length);
this.data = newData;
}
}
s.Close();
}
public bool isRunning()
{
return this.running;
}
public void Stop()
{
this.running = false;
Thread.Sleep(10);
this.recvSocket.Close();
System.IO.File.Delete(this.unixSocketpath);
}
public bool hasData()
{
return this.data.Length > 0;
}
public int dataLength()
{
lock (this.data)
return this.data.Length;
}
public byte[] getData()
{
lock (this.data)
{
var d = this.data;
this.data = new byte[0];
return d;
}
}
public byte[] getData(int length)
{
lock (this.data)
{
if (this.data.Length < length)
return this.getData();
//var d = this.data.Take(length).ToArray();
//var rest = new byte[0];
byte[] taken = new byte[length];
byte[] rest = new byte[this.data.Length - length];
Buffer.BlockCopy(this.data, 0, taken, 0, length);
Buffer.BlockCopy(this.data, length, rest, 0, rest.Length);
this.data = rest;
return taken;
}
}
}
}
这是一个 litte 程序,您可以在其中了解如何使用该类:
using System;
using System.Threading;
using mps.unix.socket;
namespace TEST_mps.unix.socket
{
class Program { static void Main(string[] args) { var P = new TEST(); } }
class TEST
{
public TEST()
{
var v = new UnixSocket("/tmp/test.mps.unix.sock");
Thread t = new Thread(delegate () { runner(v); });
t.Start();
}
private void runner(UnixSocket s)
{
while (s.isRunning())
{
Thread.Sleep(5);
if (s.hasData())
{
string responseData = System.Text.Encoding.ASCII.GetString(s.getData());
Console.WriteLine("Message received: {0}", responseData);
if (responseData == "END")
s.Stop();
}
}
}
}
}
我用 linux-x64 的 .Net 6.0 编译了这个。
为了进行测试,请运行软件,然后将一些内容发送到套接字:
在服务器上:
root@server:# ./test.mps.unix.socket
Message received: this is a message for the socket!
Message received: here is another one..
Message received: END
root@server:#
从另一个外壳:
root@server:# echo -n 'this is a message for the socket!' | socat UNIX-CONNECT:/tmp/test.mps.unix.sock STDIO
root@server:# echo -n 'here is another one..' | socat UNIX-CONNECT:/tmp/test.mps.unix.sock STDIO
root@server:# echo -n 'END' | socat UNIX-CONNECT:/tmp/test.mps.unix.sock STDIO
如果您发现错误或可以进行改进,请告诉我,我会看看我们是否可以将其添加到示例中:)