SignalR客户端与服务器SSL加密通信及跨机连接故障排查

我用C# .NET Framework实现了SignalR客户端与服务器的基础连接，代码如下：

客户端代码 #

using Microsoft.AspNet.SignalR.Client;
namespace WinFormsClient
{
    public partial class FrmClient : Form
    {
        //Connection to a SignalR server
        HubConnection _signalRConnection;

        //Proxy object for a hub hosted on the SignalR server
        IHubProxy _hubProxy;
        private async Task connectAsync()
        {
            //Set Certificate callback
            ServicePointManager.ServerCertificateValidationCallback = ValidateServerCertificate;
            //Create a connection for the SignalR server
            _signalRConnection = new HubConnection("https://10.224.10.10:12316/signalr/SimpleHub/");
            _signalRConnection.StateChanged += HubConnection_StateChanged;
            _signalRConnection.Closed += HubConnection_Closed;

            //Get a proxy object that will be used to interact with the specific hub on the server
            //Ther may be many hubs hosted on the server, so provide the type name for the hub
            _hubProxy = _signalRConnection.CreateHubProxy("SimpleHub");

            //Reigster to the "AddMessage" callback method of the hub
            //This method is invoked by the hub
            _hubProxy.On<string, string>("AddMessage", (name, message) => writeToLog($"{name}:{message}"));            

            try
            {
                //Connect to the server
                await _signalRConnection.Start();

                //Send user name for this client, so we won't need to send it with every message
                await _hubProxy.Invoke("SetUserName", txtUserName.Text);
            }
            catch (Exception ex)
            {
                writeToLog($"Error:{ex.Message}");
            }
        }
        private static bool ValidateServerCertificate(object sender, X509Certificate certificate, X509Chain chain, SslPolicyErrors sslPolicyErros)
        {
            return true;
        }
    }
}

服务器代码 #

using Microsoft.Owin.Hosting;
using Microsoft.AspNet.SignalR;
using System.ComponentModel;

namespace WinFormsServer
{
    public partial class FrmServer : Form
    {
        private IDisposable _signalR;
        private void btnStartServer_Click(object sender, EventArgs e)
        {
            try
            {
                //Start SignalR server with the give URL address
                //Final server address will be "URL/signalr"
                //Startup.Configuration is called automatically
                _signalR = WebApp.Start<Startup>("https://localhost:12316");
                writeToLog($"Server started at:{txtUrl.Text}");
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message, "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
            }
        }
    }
}

using Owin;
using Microsoft.Owin.Cors;

namespace WinFormsServer
{
    class Startup
    {
        public void Configuration(IAppBuilder app)
        {
            //CORS need to be enabled for calling SignalR service 
            app.UseCors(CorsOptions.AllowAll);
            //Find and reigster SignalR hubs
            app.MapSignalR();
        }
    }
}

初始连接问题 #

客户端与服务器部署在同一机器，已通过命令Netsh http add sslcert ipport=10.224.10.10:12316 certificate=xxxx appid={xxxx}绑定自签名SSL证书到指定IP和端口。服务器启动正常，但客户端连接时报错：

StatusCode:400, ReasonPhrase:'Bad Request', Version: 1.1, Content: System.Net.Http.SteamContent, Headers:
{
    Connection: close
    Data: Mon, 20 Nov 2023 04:41:15 GMT
    Server: Microsoft-HTTPAPI/2.0
    Content-Length:334
    Content-Type:text/html; charset=us-ascii
}

已将自签名证书导入MMC控制台的个人和受信任根证书颁发机构（本地计算机和当前用户），问题仍存在。

另外，将服务器启动URL改为https://10.224.10.10:12316/时，服务器启动失败，提示Inner Exception HttpListenerException: Access is denied，已在本地入站规则中添加服务名称并绑定12316端口，询问是否还需其他配置。

2023-11-21 更新问题 #

已解决服务器启动权限问题：以管理员身份运行服务器即可使用公网IP启动SignalR服务器。但新问题出现：已配置入站规则，其他客户端机器仍无法访问SignalR服务器，客户端使用https://公网IP:12316/signalr/SimpleHub/连接时，报错：

An error occurred while sending the request.
SocketException: A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond 10.224.10.10:12316

请求协助排查上述问题。

内容的提问来源于stack exchange，提问作者RunXin Shirley