Reorganize and cleanup

This commit is contained in:
Ben Meadors
2025-04-16 09:15:27 -05:00
parent d9632d3501
commit 84fcd568a1

View File

@@ -13,132 +13,191 @@ using System.Security.Authentication;
using System.Security.Cryptography.X509Certificates;
using System.Reflection;
var mqttFactory = new MqttServerFactory();
await RunMqttServer(args);
// #if SSL
var currentPath = Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location)!;
#pragma warning disable SYSLIB0057 // Type or member is obsolete
var certificate = new X509Certificate2(Path.Combine(currentPath, "certificate.pfx"), "large4cats", X509KeyStorageFlags.Exportable);
#pragma warning restore SYSLIB0057 // Type or member is obsolete
var mqttServerOptions = new MqttServerOptionsBuilder()
.WithoutDefaultEndpoint() // This call disables the default unencrypted endpoint on port 1883
.WithEncryptedEndpoint()
.WithEncryptedEndpointPort(8883)
.WithEncryptionCertificate(certificate.Export(X509ContentType.Pfx))
.WithEncryptionSslProtocol(SslProtocols.Tls12)
.Build();
Log.Logger.Information("Using SSL certificate for MQTT server");
// If you want to use a non-encrypted MQTT server, you can uncomment the following lines instead of the above
// var mqttServerOptions = new MqttServerOptionsBuilder()
// .WithDefaultEndpoint()
// .WithDefaultEndpointPort(1883)
// .Build();
// Log.Logger.Information("Using unencrypted MQTT server");
// #endif
Log.Logger = new LoggerConfiguration()
.MinimumLevel.Debug()
.WriteTo.Console(new RenderedCompactJsonFormatter())
// .WriteTo.File(new RenderedCompactJsonFormatter(), "log.json", rollingInterval: RollingInterval.Hour) // File logging can be enabled if needed
.CreateLogger();
using var mqttServer = mqttFactory.CreateMqttServer(mqttServerOptions);
static Data? DecryptMeshPacket(ServiceEnvelope serviceEnvelope)
async Task RunMqttServer(string[] args)
{
var nonce = new NonceGenerator(serviceEnvelope.Packet.From, serviceEnvelope.Packet.Id).Create();
ConfigureLogging();
var decrypted = PacketEncryption.TransformPacket(serviceEnvelope.Packet.Encrypted.ToByteArray(), nonce, Resources.DEFAULT_PSK);
var payload = Data.Parser.ParseFrom(decrypted);
// Create and configure MQTT server
using var mqttServer = new MqttServerFactory()
.CreateMqttServer(BuildMqttServerOptions());
ConfigureMqttServer(mqttServer);
if (payload.Portnum > PortNum.UnknownApp && payload.Payload.Length > 0)
return payload;
// Set up host
using var host = CreateHostBuilder(args).Build();
await host.StartAsync();
var lifetime = host.Services.GetRequiredService<IHostApplicationLifetime>();
// Was not able to decrypt the payload
return null;
// Start MQTT server
await mqttServer.StartAsync();
// Configure graceful shutdown
await SetupGracefulShutdown(mqttServer, lifetime, host);
}
mqttServer.InterceptingPublishAsync += async (args) =>
void ConfigureLogging()
{
Log.Logger = new LoggerConfiguration()
.MinimumLevel.Debug()
.WriteTo.Console(new RenderedCompactJsonFormatter())
// .WriteTo.File(new RenderedCompactJsonFormatter(), "log.json", rollingInterval: RollingInterval.Hour)
.CreateLogger();
}
MqttServerOptions BuildMqttServerOptions()
{
var currentPath = Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location)!;
#pragma warning disable SYSLIB0057 // Type or member is obsolete
var certificate = new X509Certificate2(
Path.Combine(currentPath, "certificate.pfx"),
"large4cats",
X509KeyStorageFlags.Exportable);
#pragma warning restore SYSLIB0057
var options = new MqttServerOptionsBuilder()
.WithoutDefaultEndpoint()
.WithEncryptedEndpoint()
.WithEncryptedEndpointPort(8883)
.WithEncryptionCertificate(certificate.Export(X509ContentType.Pfx))
.WithEncryptionSslProtocol(SslProtocols.Tls12)
.Build();
Log.Logger.Information("Using SSL certificate for MQTT server");
return options;
}
void ConfigureMqttServer(MqttServer mqttServer)
{
mqttServer.InterceptingPublishAsync += HandleInterceptingPublish;
mqttServer.InterceptingSubscriptionAsync += HandleInterceptingSubscription;
mqttServer.ValidatingConnectionAsync += HandleValidatingConnection;
}
async Task HandleInterceptingPublish(InterceptingPublishEventArgs args)
{
try
{
if (args.ApplicationMessage.Payload.Length == 0)
{
Log.Logger.Warning("Received empty payload on topic {@Topic} from {@ClientId}", args.ApplicationMessage.Topic, args.ClientId);
args.ProcessPublish = false; // This will block empty packets
args.ProcessPublish = false;
return;
}
var serviceEnvelope = ServiceEnvelope.Parser.ParseFrom(args.ApplicationMessage.Payload);
// Block malformed service envelopes / packets
if (
String.IsNullOrWhiteSpace(serviceEnvelope.ChannelId) ||
if (!IsValidServiceEnvelope(serviceEnvelope))
{
Log.Logger.Warning("Service envelope or packet is malformed. Blocking packet on topic {@Topic} from {@ClientId}",
args.ApplicationMessage.Topic, args.ClientId);
args.ProcessPublish = false;
return;
}
// Spot for any async operations we might want to perform
await Task.FromResult(0);
var data = DecryptMeshPacket(serviceEnvelope);
// Uncomment to block unrecognized packets
// if (data == null)
// {
// Log.Logger.Warning("Service envelope does not contain a valid packet. Blocking packet");
// args.ProcessPublish = false;
// return;
// }
LogReceivedMessage(args.ApplicationMessage.Topic, args.ClientId, data);
args.ProcessPublish = true;
}
catch (InvalidProtocolBufferException)
{
Log.Logger.Warning("Failed to decode presumed protobuf packet. Blocking");
args.ProcessPublish = false;
}
catch (Exception ex)
{
Log.Logger.Error("Exception occurred while processing packet on {@Topic} from {@ClientId}: {@Exception}",
args.ApplicationMessage.Topic, args.ClientId, ex.Message);
args.ProcessPublish = false;
}
}
Task HandleInterceptingSubscription(InterceptingSubscriptionEventArgs args)
{
args.ProcessSubscription = true; // Add filtering logic here if needed
return Task.CompletedTask;
}
Task HandleValidatingConnection(ValidatingConnectionEventArgs args)
{
// Add authentication logic here
args.ReasonCode = MqttConnectReasonCode.Success;
return Task.CompletedTask;
}
bool IsValidServiceEnvelope(ServiceEnvelope serviceEnvelope)
{
return !(String.IsNullOrWhiteSpace(serviceEnvelope.ChannelId) ||
String.IsNullOrWhiteSpace(serviceEnvelope.GatewayId) ||
serviceEnvelope.Packet == null ||
serviceEnvelope.Packet.Id < 1 ||
serviceEnvelope.Packet.From < 1 ||
serviceEnvelope.Packet.Encrypted == null ||
serviceEnvelope.Packet.Encrypted.Length < 1 ||
serviceEnvelope.Packet.Decoded != null)
{
Log.Logger.Warning("Service envelope or packet is malformed. Blocking packet on topic {@Topic} from {@ClientId}", args.ApplicationMessage.Topic, args.ClientId);
args.ProcessPublish = false;
return;
}
serviceEnvelope.Packet.Decoded != null);
}
var data = DecryptMeshPacket(serviceEnvelope);
// If we were not able to decrypt the packet, it is likely encrypted with an unknown PSK
// Uncomment the following lines if you want to block these packets
// if (data == null)
// {
// Log.Logger.Warning("Service envelope does not contain a valid packet. Blocking packet");
// args.ProcessPublish = false; // This will block packets that are not valid protobuf packets
// return;
// }
if (data?.Portnum == PortNum.TextMessageApp)
{
Log.Logger.Information("Received text message on topic {@Topic} from {@ClientId}: {@Message}",
args.ApplicationMessage.Topic, args.ClientId, data.Payload.ToStringUtf8());
}
else
{
Log.Logger.Information("Received packet on topic {@Topic} from {@ClientId} with port number: {@Portnum}",
args.ApplicationMessage.Topic, args.ClientId, data?.Portnum);
}
// Any further validation logic to block a packet can be added here
args.ProcessPublish = true;
}
catch (InvalidProtocolBufferException)
{
Log.Logger.Warning("Failed to decode presumed protobuf packet. Blocking");
args.ProcessPublish = false; // This will block packets encrypted on unknown PSKs
}
catch (Exception ex)
{
Log.Logger.Error("Exception occured while attempting to decode packet on {@Topic} from {@ClientId}: {@Exception}", args.ApplicationMessage.Topic, args.ClientId, ex.Message);
args.ProcessPublish = false; // This will block packets that caused us to encounter an exception
}
};
mqttServer.InterceptingSubscriptionAsync += (args) =>
void LogReceivedMessage(string topic, string clientId, Data? data)
{
args.ProcessSubscription = true; // Subscription filtering logic can be added here to only allow certain topics
if (data?.Portnum == PortNum.TextMessageApp)
{
Log.Logger.Information("Received text message on topic {@Topic} from {@ClientId}: {@Message}",
topic, clientId, data.Payload.ToStringUtf8());
}
else
{
Log.Logger.Information("Received packet on topic {@Topic} from {@ClientId} with port number: {@Portnum}",
topic, clientId, data?.Portnum);
}
}
return Task.CompletedTask;
};
mqttServer.ValidatingConnectionAsync += (args) =>
static Data? DecryptMeshPacket(ServiceEnvelope serviceEnvelope)
{
args.ReasonCode = true ? // Authentication logic can be added here
MqttConnectReasonCode.Success : MqttConnectReasonCode.BadUserNameOrPassword;
var nonce = new NonceGenerator(serviceEnvelope.Packet.From, serviceEnvelope.Packet.Id).Create();
var decrypted = PacketEncryption.TransformPacket(serviceEnvelope.Packet.Encrypted.ToByteArray(), nonce, Resources.DEFAULT_PSK);
var payload = Data.Parser.ParseFrom(decrypted);
// You can block connections based on client ID, username, ip, etc.
return Task.CompletedTask;
};
if (payload.Portnum > PortNum.UnknownApp && payload.Payload.Length > 0)
return payload;
return null;
}
async Task SetupGracefulShutdown(MqttServer mqttServer, IHostApplicationLifetime lifetime, IHost host)
{
var ended = new ManualResetEventSlim();
var starting = new ManualResetEventSlim();
AssemblyLoadContext.Default.Unloading += ctx =>
{
starting.Set();
Log.Logger.Debug("Waiting for completion");
ended.Wait();
};
starting.Wait();
Log.Logger.Debug("Received signal gracefully shutting down");
await mqttServer.StopAsync();
Thread.Sleep(500);
ended.Set();
lifetime.StopApplication();
host.WaitForShutdownAsync().Wait();
}
static IHostBuilder CreateHostBuilder(string[] args)
{
@@ -146,33 +205,6 @@ static IHostBuilder CreateHostBuilder(string[] args)
.UseConsoleLifetime()
.ConfigureServices((hostContext, services) =>
{
services
.AddSingleton(Console.Out);
services.AddSingleton(Console.Out);
});
}
using var host = CreateHostBuilder(args).Build();
await host.StartAsync();
var lifetime = host.Services.GetRequiredService<IHostApplicationLifetime>();
await mqttServer.StartAsync();
var ended = new ManualResetEventSlim();
var starting = new ManualResetEventSlim();
AssemblyLoadContext.Default.Unloading += ctx =>
{
starting.Set();
Log.Logger.Debug("Waiting for completion");
ended.Wait();
};
starting.Wait();
Log.Logger.Debug("Received signal gracefully shutting down");
await mqttServer.StopAsync();
Thread.Sleep(1000);
ended.Set();
lifetime.StopApplication();
await host.WaitForShutdownAsync();