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在我的 MQTT 代理中，当活动 TLS 1.2 客户端无法连接到代理并获得此异常时

远程证书被提供的 RemoteCertificateValidationCallback 拒绝

注意：我使用由 openssl 生成的自签名证书。

经纪人代码

using MQTTnet.Server;
using System;
using MQTTnet;
using System.Text;
using static System.Console;
using System.Threading;
using System.Security.Cryptography.X509Certificates;
using SharedItems;

var wait = new ManualResetEvent(false);

var option = new MqttServerOptionsBuilder()
    .WithEncryptedEndpoint()
    .WithEncryptedEndpointPort(8200)
    .WithEncryptionCertificate(ConfigCertificate.GetCertificate().Export(X509ContentType.Pfx))
    .WithEncryptionSslProtocol(System.Security.Authentication.SslProtocols.Tls12)
    .WithConnectionValidator(OnNewConnection)
    .WithApplicationMessageInterceptor(OnNewMessage);
var mqttServer = new MqttFactory().CreateMqttServer();
await mqttServer.StartAsync(option.Build());
wait.WaitOne();

static void OnNewConnection(MqttConnectionValidatorContext context)
{
    WriteLine(
            "New connection: ClientId = {0}, Endpoint = {1}",
            context.ClientId,
            context.Endpoint);
}

static void OnNewMessage(MqttApplicationMessageInterceptorContext context)
{
    var payload = context.ApplicationMessage?.Payload == null ? null : Encoding.UTF8.GetString(context.ApplicationMessage?.Payload);
    WriteLine(
        " TimeStamp: {0} -- Message: ClientId = {1}, Topic = {2}, Payload = {3}, QoS = {4}, Retain-Flag = {5}",

        DateTime.Now,
        context.ClientId,
        context.ApplicationMessage?.Topic,
        payload,
        context.ApplicationMessage?.QualityOfServiceLevel,
        context.ApplicationMessage?.Retain);
}

ConfigCertificate.GetCertificate方法代码（没关系并返回证书）

public static X509Certificate2 GetCertificate()
{
    var currectPath = Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location);
    var certificationPath = Path.Combine(currectPath, "Assets/key/mycert.pfx");
    return  new X509Certificate2(certificationPath, "password", X509KeyStorageFlags.Exportable);
}

mqtt 客户端代码

using System;
using MQTTnet;
using System.Text;
using static System.Console;
using MQTTnet.Client.Options;
using MQTTnet.Client.Connecting;
using MQTTnet.Client.Disconnecting;
using MQTTnet.Extensions.ManagedClient;
using System.Text.Json;
using System.Threading.Tasks;
using System.Threading;
using System.Collections.Generic;
using System.Security.Cryptography.X509Certificates;
using SharedItems;

WriteLine("Start App");
var _url = "localhost";
var _topic = "dev.to/topic/json";
var builder = new MqttClientOptionsBuilder()
    .WithClientId(Guid.NewGuid().ToString())
    .WithTls(new MqttClientOptionsBuilderTlsParameters
    {
        UseTls=true,
        Certificates=certs,
        SslProtocol=System.Security.Authentication.SslProtocols.Tls12
    })
    .WithTcpServer(_url, port);

var option = new ManagedMqttClientOptionsBuilder().WithAutoReconnectDelay(TimeSpan.FromSeconds(50)).WithClientOptions(builder.Build()).Build();

var client = new MqttFactory().CreateManagedMqttClient();
client.ConnectedHandler = new MqttClientConnectedHandlerDelegate(OnConnected);
client.ConnectingFailedHandler = new ConnectingFailedHandlerDelegate(OnConnectingFailed);
client.DisconnectedHandler = new MqttClientDisconnectedHandlerDelegate(OnDisconnected);
client.StartAsync(option).GetAwaiter().GetResult();
client.UseApplicationMessageReceivedHandler(context =>
{
    var payload = context.ApplicationMessage?.Payload == null ? null : Encoding.UTF8.GetString(context.ApplicationMessage?.Payload);

    WriteLine(
        " TimeStamp: {0} -- Message: ClientId = {1}, Topic = {2}, Payload = {3}, QoS = {4}, Retain-Flag = {5}",

        DateTime.Now,
        context.ClientId,
        context.ApplicationMessage?.Topic,
        payload,
        context.ApplicationMessage?.QualityOfServiceLevel,
        context.ApplicationMessage?.Retain);
});

while (true)
{
    if (!client.IsConnected)
        continue;
    string json = JsonSerializer.Serialize(new {id=Guid.NewGuid(), message = "Heyo :)", sent = DateTimeOffset.UtcNow });
    await client.PublishAsync(_topic, json);
    WriteLine("Send Data");
    await Task.Delay(1000);
}

static void OnConnected(MqttClientConnectedEventArgs obj)
{
    WriteLine("Successfully connected.");
}

static void OnConnectingFailed(ManagedProcessFailedEventArgs obj)
{
    WriteLine("Couldn't connect to broker."+obj.Exception.Message);
}

static void OnDisconnected(MqttClientDisconnectedEventArgs obj)
{
    WriteLine("Successfully disconnected. "+ obj.Exception.Message);
}

ConfigCertificate.GetCrtCertificate（没关系并返回证书）：

public static X509Certificate GetCrtCertificate()
{
    var currectPath = Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location);
    var certificationPath = Path.Combine(currectPath, "Assets/key/client.crt");
    return X509Certificate.CreateFromCertFile(certificationPath);
}

为什么客户端会收到此错误？修复和客户端如何连接到代理？

4

0 回答 0