async Task TryHandleClientConnectionAsync(CrossPlatformSocket clientSocket) { Stream stream = null; string remoteEndPoint = null; try { remoteEndPoint = clientSocket.RemoteEndPoint.ToString(); _logger.Verbose("Client '{0}' accepted by TCP listener '{1}, {2}'.", remoteEndPoint, _localEndPoint, _addressFamily == AddressFamily.InterNetwork ? "ipv4" : "ipv6"); clientSocket.NoDelay = _options.NoDelay; stream = clientSocket.GetStream(); X509Certificate2 clientCertificate = null; if (_tlsCertificate != null) { var sslStream = new SslStream(stream, false, _tlsOptions.RemoteCertificateValidationCallback); await sslStream.AuthenticateAsServerAsync( _tlsCertificate, _tlsOptions.ClientCertificateRequired, _tlsOptions.SslProtocol, _tlsOptions.CheckCertificateRevocation).ConfigureAwait(false); stream = sslStream; clientCertificate = sslStream.RemoteCertificate as X509Certificate2; if (clientCertificate == null && sslStream.RemoteCertificate != null) { clientCertificate = new X509Certificate2(sslStream.RemoteCertificate.Export(X509ContentType.Cert)); } } var clientHandler = ClientHandler; if (clientHandler != null) { using (var clientAdapter = new MqttChannelAdapter( new MqttTcpChannel(stream, remoteEndPoint, clientCertificate), new MqttPacketFormatterAdapter(new MqttPacketWriter()), null, _rootLogger)) { await clientHandler(clientAdapter).ConfigureAwait(false); } } } catch (Exception exception) { if (exception is ObjectDisposedException) { // It can happen that the listener socket is accessed after the cancellation token is already set and the listener socket is disposed. return; } if (exception is SocketException socketException && socketException.SocketErrorCode == SocketError.OperationAborted) { return; } _logger.Error(exception, "Error while handling client connection."); } finally { try { stream?.Dispose(); clientSocket?.Dispose(); } catch (Exception disposeException) { _logger.Error(disposeException, "Error while cleaning up client connection"); } } _logger.Verbose("Client '{0}' disconnected at TCP listener '{1}, {2}'.", remoteEndPoint, _localEndPoint, _addressFamily == AddressFamily.InterNetwork ? "ipv4" : "ipv6"); }
async Task TryHandleClientConnectionAsync(CrossPlatformSocket clientSocket) { Stream stream = null; string remoteEndPoint = null; try { remoteEndPoint = clientSocket.RemoteEndPoint.ToString(); _logger.Verbose("Client '{0}' accepted by TCP listener '{1}, {2}'.", remoteEndPoint, _localEndPoint, _addressFamily == AddressFamily.InterNetwork ? "ipv4" : "ipv6"); clientSocket.NoDelay = _options.NoDelay; stream = clientSocket.GetStream(); X509Certificate2 clientCertificate = null; if (_tlsCertificate != null) { var sslStream = new SslStream(stream, false, _tlsOptions.RemoteCertificateValidationCallback); #if NETCOREAPP3_1 || NET5_0_OR_GREATER await sslStream.AuthenticateAsServerAsync( new SslServerAuthenticationOptions() { ServerCertificate = _tlsCertificate, ClientCertificateRequired = _tlsOptions.ClientCertificateRequired, EnabledSslProtocols = _tlsOptions.SslProtocol, CertificateRevocationCheckMode = _tlsOptions.CheckCertificateRevocation ? X509RevocationMode.Online : X509RevocationMode.NoCheck, EncryptionPolicy = EncryptionPolicy.RequireEncryption, CipherSuitesPolicy = _tlsOptions.CipherSuitesPolicy }).ConfigureAwait(false); #else await sslStream.AuthenticateAsServerAsync( _tlsCertificate, _tlsOptions.ClientCertificateRequired, _tlsOptions.SslProtocol, _tlsOptions.CheckCertificateRevocation).ConfigureAwait(false); #endif stream = sslStream; clientCertificate = sslStream.RemoteCertificate as X509Certificate2; if (clientCertificate == null && sslStream.RemoteCertificate != null) { clientCertificate = new X509Certificate2(sslStream.RemoteCertificate.Export(X509ContentType.Cert)); } } var clientHandler = ClientHandler; if (clientHandler != null) { var tcpChannel = new MqttTcpChannel(stream, remoteEndPoint, clientCertificate); var bufferWriter = new MqttBufferWriter(_serverOptions.WriterBufferSize, _serverOptions.WriterBufferSizeMax); var packetFormatterAdapter = new MqttPacketFormatterAdapter(bufferWriter); using (var clientAdapter = new MqttChannelAdapter(tcpChannel, packetFormatterAdapter, null, _rootLogger)) { await clientHandler(clientAdapter).ConfigureAwait(false); } } } catch (Exception exception) { if (exception is ObjectDisposedException) { // It can happen that the listener socket is accessed after the cancellation token is already set and the listener socket is disposed. return; } if (exception is SocketException socketException && socketException.SocketErrorCode == SocketError.OperationAborted) { return; } _logger.Error(exception, "Error while handling client connection."); } finally { try { stream?.Dispose(); clientSocket?.Dispose(); } catch (Exception disposeException) { _logger.Error(disposeException, "Error while cleaning up client connection"); } } _logger.Verbose("Client '{0}' disconnected at TCP listener '{1}, {2}'.", remoteEndPoint, _localEndPoint, _addressFamily == AddressFamily.InterNetwork ? "ipv4" : "ipv6"); }