public SessionContext(Byte[] SessionToken) { this.SessionTokenValue = SessionToken; this.SessionTokenStringValue = Cryptography.BytesToHexString(SessionToken.Reverse()); }
public void Start() { var Success = false; try { IsRunningValue.Update ( b => { if (b) { throw new InvalidOperationException(); } if (BindingsValue.Length == 0) { throw new Exception("NoValidBinding"); } ListeningTaskTokenSource = new CancellationTokenSource(); var ListeningTaskToken = ListeningTaskTokenSource.Token; Action <UdpSession> Purify = StoppingSession => { SessionSets.DoAction ( ss => { if (ss.Sessions.Contains(StoppingSession)) { ss.Sessions.Remove(StoppingSession); var IpAddress = StoppingSession.RemoteEndPoint.Address; var isi = ss.IpSessions[IpAddress]; if (isi.Authenticated.Contains(StoppingSession)) { isi.Authenticated.Remove(StoppingSession); } isi.Count -= 1; if (isi.Count == 0) { ss.IpSessions.Remove(IpAddress); } var SessionId = StoppingSession.SessionId; ss.SessionIdToSession.Remove(SessionId); } } ); StoppingSession.Dispose(); }; Action <AcceptingInfo> Accept = a => { var ep = a.RemoteEndPoint; UdpSession s = null; try { var Buffer = a.ReadBuffer; if (Buffer.Length < 12) { return; } var SessionId = Buffer[0] | ((Int32)(Buffer[1]) << 8) | ((Int32)(Buffer[2]) << 16) | ((Int32)(Buffer[3]) << 24); var Flag = Buffer[4] | ((Int32)(Buffer[5]) << 8); var Index = Buffer[6] | ((Int32)(Buffer[7]) << 8); var Verification = Buffer[8] | ((Int32)(Buffer[9]) << 8) | ((Int32)(Buffer[10]) << 16) | ((Int32)(Buffer[11]) << 24); Buffer[8] = 0; Buffer[9] = 0; Buffer[10] = 0; Buffer[11] = 0; if (ServerContext.EnableLogTransport) { //按Flag中是否包含AUX分别生成日志 if ((Flag & 8) != 0) { ServerContext.RaiseSessionLog(new SessionLogEntry { Token = SessionId.ToString("X8"), RemoteEndPoint = ep, Time = DateTime.UtcNow, Type = "UdpTransport", Name = "ReceiveAux", Message = "AckIndex: " + Index.ToInvariantString() + " Length: " + Buffer.Length.ToInvariantString() }); } else { ServerContext.RaiseSessionLog(new SessionLogEntry { Token = SessionId.ToString("X8"), RemoteEndPoint = ep, Time = DateTime.UtcNow, Type = "UdpTransport", Name = "Receive", Message = "Index: " + Index.ToInvariantString() + " Length: " + Buffer.Length.ToInvariantString() }); } } //如果Flag中不包含ENC,则验证CRC32 if ((Flag & 2) == 0) { if (Cryptography.CRC32(Buffer) != Verification) { if (ServerContext.EnableLogTransport) { ServerContext.RaiseSessionLog(new SessionLogEntry { Token = SessionId.ToString("X8"), RemoteEndPoint = ep, Time = DateTime.UtcNow, Type = "UdpTransport", Name = "Receive", Message = "Index: " + Index.ToInvariantString() + " CRC32Failed" }); } return; } } //如果Flag中包含INI,则初始化 if ((Flag & 4) != 0) { if ((Flag & 1) != 0) { return; } if ((Flag & 2) != 0) { return; } if ((Flag & 8) != 0) { return; } var Offset = 12; s = new UdpSession(this, a.Socket, ep, VirtualTransportServerFactory, QueueUserWorkItem); SessionId = s.SessionId; if (MaxConnectionsValue.HasValue && (SessionSets.Check(ss => ss.Sessions.Count) >= MaxConnectionsValue.Value)) { PurifyConsumer.DoOne(); } if (MaxConnectionsValue.HasValue && (SessionSets.Check(ss => ss.Sessions.Count) >= MaxConnectionsValue.Value)) { try { s.Start(); OnMaxConnectionsExceeded(s); } finally { s.Dispose(); } return; } if (MaxConnectionsPerIPValue.HasValue && (SessionSets.Check(ss => ss.IpSessions.ContainsKey(ep.Address) ? ss.IpSessions[ep.Address].Count : 0) >= MaxConnectionsPerIPValue.Value)) { try { s.Start(); OnMaxConnectionsPerIPExceeded(s); } finally { PurifyConsumer.Push(s); } return; } if (MaxUnauthenticatedPerIPValue.HasValue && (SessionSets.Check(ss => ss.IpSessions.ContainsKey(ep.Address) ? (ss.IpSessions[ep.Address].Count - ss.IpSessions[ep.Address].Authenticated.Count) : 0) >= MaxUnauthenticatedPerIPValue.Value)) { try { s.Start(); OnMaxConnectionsPerIPExceeded(s); } finally { PurifyConsumer.Push(s); } return; } SessionSets.DoAction ( ss => { ss.Sessions.Add(s); if (ss.IpSessions.ContainsKey(ep.Address)) { ss.IpSessions[ep.Address].Count += 1; } else { var isi = new IpSessionInfo(); isi.Count += 1; ss.IpSessions.Add(ep.Address, isi); } while ((SessionId == 0) || ss.SessionIdToSession.ContainsKey(SessionId)) { s = new UdpSession(this, a.Socket, ep, VirtualTransportServerFactory, QueueUserWorkItem); SessionId = s.SessionId; } ss.SessionIdToSession.Add(SessionId, s); } ); s.Start(); s.PrePush(() => { if (!s.Push(ep, Index, null, Buffer, Offset, Buffer.Length - Offset)) { PurifyConsumer.Push(s); } }); } else { var Close = false; SessionSets.DoAction ( ss => { if (!ss.SessionIdToSession.ContainsKey(SessionId)) { Close = true; return; } s = ss.SessionIdToSession[SessionId]; } ); if (Close) { return; } s.PrePush(() => { var IsEncrypted = (Flag & 2) != 0; var NextSecureContext = s.NextSecureContext; var SecureContext = s.SecureContext; if ((SecureContext == null) && (NextSecureContext != null)) { s.SecureContext = NextSecureContext; s.NextSecureContext = null; SecureContext = NextSecureContext; NextSecureContext = null; } if ((SecureContext != null) != IsEncrypted) { return; } if (IsEncrypted) { var Key = SecureContext.ClientToken.Concat(Cryptography.SHA256(Buffer.Skip(4).Take(4))); var HMACBytes = Cryptography.HMACSHA256Simple(Key, Buffer).Take(4).ToArray(); var HMAC = HMACBytes[0] | ((Int32)(HMACBytes[1]) << 8) | ((Int32)(HMACBytes[2]) << 16) | ((Int32)(HMACBytes[3]) << 24); if (HMAC != Verification) { if (ServerContext.EnableLogTransport) { ServerContext.RaiseSessionLog(new SessionLogEntry { Token = SessionId.ToString("X8"), RemoteEndPoint = ep, Time = DateTime.UtcNow, Type = "UdpTransport", Name = "Receive", Message = "Index: " + Index.ToInvariantString() + " HMACFailed" }); } return; } } var Offset = 12; int[] Indices = null; if ((Flag & 1) != 0) { if (Buffer.Length < 14) { return; } var NumIndex = Buffer[Offset] | ((Int32)(Buffer[Offset + 1]) << 8); if (Buffer.Length < 14 + NumIndex * 2) { return; } if (NumIndex > UdpSession.WritingWindowSize) //若Index数量较大,则丢弃包 { return; } Offset += 2; Indices = new int[NumIndex]; for (int k = 0; k < NumIndex; k += 1) { Indices[k] = Buffer[Offset + k * 2] | ((Int32)(Buffer[Offset + k * 2 + 1]) << 8); } Offset += NumIndex * 2; } //如果Flag中包含AUX,则判断 if ((Flag & 8) != 0) { if (Indices == null) { return; } if (Indices.Length < 1) { return; } if (Index != Indices[0]) { return; } if (Offset != Buffer.Length) { return; } } var PreviousRemoteEndPoint = s.RemoteEndPoint; if (!PreviousRemoteEndPoint.Equals(ep)) { SessionSets.DoAction ( ss => { var Authenticated = false; { var PreviousIpAddress = PreviousRemoteEndPoint.Address; var isi = ss.IpSessions[PreviousIpAddress]; if (isi.Authenticated.Contains(s)) { isi.Authenticated.Remove(s); Authenticated = true; } isi.Count -= 1; if (isi.Count == 0) { ss.IpSessions.Remove(PreviousIpAddress); } } { IpSessionInfo isi; if (ss.IpSessions.ContainsKey(ep.Address)) { isi = ss.IpSessions[ep.Address]; isi.Count += 1; } else { isi = new IpSessionInfo(); isi.Count += 1; ss.IpSessions.Add(ep.Address, isi); } if (Authenticated) { isi.Authenticated.Add(s); } } s.RemoteEndPoint = ep; } ); } if ((Flag & 8) != 0) { if (!s.PushAux(ep, Indices)) { PurifyConsumer.Push(s); } } else { if (!s.Push(ep, Index, Indices, Buffer, Offset, Buffer.Length - Offset)) { PurifyConsumer.Push(s); } } }); } } catch (Exception ex) { if (ServerContext.EnableLogSystem) { ServerContext.RaiseSessionLog(new SessionLogEntry { Token = "", RemoteEndPoint = ep, Time = DateTime.UtcNow, Type = "Sys", Name = "Exception", Message = ExceptionInfo.GetExceptionInfo(ex) }); } if (s != null) { PurifyConsumer.Push(s); } } }; AcceptConsumer = new AsyncConsumer <AcceptingInfo>(QueueUserWorkItem, a => { Accept(a); return(true); }, int.MaxValue); var Exceptions = new List <Exception>(); var Bindings = new List <IPEndPoint>(); //将所有默认地址换为实际的所有接口地址 foreach (var Binding in BindingsValue) { if (IPAddress.Equals(Binding.Address, IPAddress.Any) || IPAddress.Equals(Binding.Address, IPAddress.IPv6Any)) { foreach (var ni in NetworkInterface.GetAllNetworkInterfaces()) { foreach (var a in ni.GetIPProperties().UnicastAddresses) { if (a.Address.AddressFamily == Binding.Address.AddressFamily) { Bindings.Add(new IPEndPoint(a.Address, Binding.Port)); } } } } else { Bindings.Add(Binding); } } foreach (var Binding in Bindings) { Func <Socket> CreateSocket = () => { var s = new Socket(Binding.AddressFamily, SocketType.Dgram, ProtocolType.Udp); //在Windows下关闭SIO_UDP_CONNRESET报告,防止接受数据出错 //http://support.microsoft.com/kb/263823/en-us if (System.Environment.OSVersion.Platform == PlatformID.Win32NT) { uint IOC_IN = 0x80000000; uint IOC_VENDOR = 0x18000000; uint SIO_UDP_CONNRESET = IOC_IN | IOC_VENDOR | 12; s.IOControl(unchecked ((int)(SIO_UDP_CONNRESET)), new byte[] { Convert.ToByte(false) }, null); } return(s); }; var Socket = CreateSocket(); try { Socket.Bind(Binding); } catch (SocketException ex) { Exceptions.Add(ex); continue; } var BindingInfo = new BindingInfo(); BindingInfo.EndPoint = Binding; BindingInfo.Socket = new LockedVariable <Socket>(Socket); Func <SocketAsyncEventArgs, Boolean> Completed = args => { try { if (ListeningTaskToken.IsCancellationRequested) { return(false); } if (args.SocketError == SocketError.Success) { var Count = args.BytesTransferred; var ReadBuffer = new Byte[Count]; Array.Copy(BindingInfo.ReadBuffer, ReadBuffer, Count); var a = new AcceptingInfo { Socket = BindingInfo.Socket.Check(s => s), ReadBuffer = ReadBuffer, RemoteEndPoint = (IPEndPoint)(args.RemoteEndPoint) }; AcceptConsumer.Push(a); } else { BindingInfo.Socket.Update ( OriginalSocket => { try { OriginalSocket.Dispose(); } catch (Exception) { } var NewSocket = CreateSocket(); NewSocket.Bind(Binding); return(NewSocket); } ); } } finally { args.Dispose(); } BindingInfo.Start(); return(true); }; BindingInfo.ListenConsumer = new AsyncConsumer <SocketAsyncEventArgs>(QueueUserWorkItem, Completed, 1); BindingInfo.Start = () => { var EventArgs = new SocketAsyncEventArgs(); EventArgs.RemoteEndPoint = new IPEndPoint(Binding.Address.AddressFamily == AddressFamily.InterNetworkV6 ? IPAddress.IPv6Any : IPAddress.Any, 0); EventArgs.SetBuffer(BindingInfo.ReadBuffer, 0, BindingInfo.ReadBuffer.Length); var bs = BindingInfo.Socket.Check(s => s); EventArgs.Completed += (o, args) => BindingInfo.ListenConsumer.Push(args); try { if (!bs.ReceiveFromAsync(EventArgs)) { BindingInfo.ListenConsumer.Push(EventArgs); } } catch (ObjectDisposedException) { } }; BindingInfos.Add(BindingInfo); } if (BindingInfos.Count == 0) { throw new AggregateException(Exceptions); } PurifyConsumer = new AsyncConsumer <UdpSession>(PurifierQueueUserWorkItem, s => { Purify(s); return(true); }, int.MaxValue); if (UnauthenticatedSessionIdleTimeoutValue.HasValue || SessionIdleTimeoutValue.HasValue) { var TimePeriod = TimeSpan.FromSeconds(Math.Max(TimeoutCheckPeriodValue, 1)); LastActiveTimeCheckTimer = new Timer(state => { if (UnauthenticatedSessionIdleTimeoutValue.HasValue) { var CheckTime = DateTime.UtcNow.AddIntSeconds(-UnauthenticatedSessionIdleTimeoutValue.Value); SessionSets.DoAction ( ss => { foreach (var s in ss.Sessions) { var IpAddress = s.RemoteEndPoint.Address; var isi = ss.IpSessions[IpAddress]; if (!isi.Authenticated.Contains(s)) { if (s.LastActiveTime < CheckTime) { PurifyConsumer.Push(s); } } } } ); } if (SessionIdleTimeoutValue.HasValue) { var CheckTime = DateTime.UtcNow.AddIntSeconds(-SessionIdleTimeoutValue.Value); SessionSets.DoAction ( ss => { foreach (var s in ss.Sessions) { var IpAddress = s.RemoteEndPoint.Address; var isi = ss.IpSessions[IpAddress]; if (isi.Authenticated.Contains(s)) { if (s.LastActiveTime < CheckTime) { PurifyConsumer.Push(s); } } } } ); } }, null, TimePeriod, TimePeriod); } foreach (var BindingInfo in BindingInfos) { BindingInfo.Start(); } Success = true; return(true); } ); } finally { if (!Success) { Stop(); } } }
public ISessionContext CreateSessionContext() { return(new SessionContext(Cryptography.CreateRandom(4))); }
public void Start() { var Success = false; try { IsRunningValue.Update ( b => { if (b) { throw new InvalidOperationException(); } if (BindingsValue.Length == 0) { throw new Exception("NoValidBinding"); } ListeningTaskTokenSource = new CancellationTokenSource(); var ListeningTaskToken = ListeningTaskTokenSource.Token; foreach (var Binding in BindingsValue) { Listener.Prefixes.Add(Binding); } if (UnauthenticatedSessionIdleTimeoutValue.HasValue) { SetTimer(Listener, UnauthenticatedSessionIdleTimeoutValue.Value); } Action <HttpListenerContext> PurifyContext = ListenerContext => { try { ListenerContext.Response.Close(); } catch { } }; Action <HttpSession> Purify = StoppingSession => { SessionSets.DoAction ( ss => { if (ss.Sessions.Contains(StoppingSession)) { ss.Sessions.Remove(StoppingSession); var IpAddress = StoppingSession.RemoteEndPoint.Address; var isi = ss.IpSessions[IpAddress]; if (isi.Authenticated.Contains(StoppingSession)) { isi.Authenticated.Remove(StoppingSession); } isi.Count -= 1; if (isi.Count == 0) { ss.IpSessions.Remove(IpAddress); } var SessionId = ss.SessionToId[StoppingSession]; ss.SessionIdToSession.Remove(SessionId); ss.SessionToId.Remove(StoppingSession); } } ); StoppingSession.Dispose(); }; Action <HttpListenerContext> Accept = a => { IPEndPoint e = null; try { e = (IPEndPoint)a.Request.RemoteEndPoint; var XForwardedFor = a.Request.Headers["X-Forwarded-For"]; var Address = e.Address; if ((XForwardedFor != null) && (XForwardedFor != "")) { try { IPAddress addr; if (IPAddress.TryParse(XForwardedFor.Split(',')[0].Trim(' '), out addr)) { Address = addr; } } catch { } } var XForwardedPort = a.Request.Headers["X-Forwarded-Port"]; var Port = e.Port; if ((XForwardedPort != null) && (XForwardedPort != "")) { try { int p; if (int.TryParse(XForwardedPort.Split(',')[0].Trim(' '), out p)) { Port = p; } } catch { } } e = new IPEndPoint(Address, Port); if (ServerContext.EnableLogSystem) { ServerContext.RaiseSessionLog(new SessionLogEntry { Token = "", RemoteEndPoint = e, Time = DateTime.UtcNow, Type = "Sys", Name = "RequestIn", Message = "" }); } if (a.Request.ContentLength64 < 0) { a.Response.StatusCode = 411; NotifyListenerContextQuit(a); return; } if (a.Request.ContentLength64 > ReadBufferSize) { a.Response.StatusCode = 413; NotifyListenerContextQuit(a); return; } if (!IsMatchBindingName(a.Request.Url)) { a.Response.StatusCode = 404; NotifyListenerContextQuit(a); return; } var Headers = a.Request.Headers.AllKeys.ToDictionary(k => k, k => a.Request.Headers[k]); if (Headers.ContainsKey("Range")) { a.Response.StatusCode = 400; NotifyListenerContextQuit(a); return; } if (Headers.ContainsKey("Accept-Charset")) { var AcceptCharsetParts = Headers["Accept-Charset"].Split(';'); if (AcceptCharsetParts.Length == 0) { a.Response.StatusCode = 400; NotifyListenerContextQuit(a); return; } var EncodingNames = AcceptCharsetParts[0].Split(',').Select(n => n.Trim(' ')).ToArray(); if (!(EncodingNames.Contains("utf-8", StringComparer.OrdinalIgnoreCase) || EncodingNames.Contains("*", StringComparer.OrdinalIgnoreCase))) { a.Response.StatusCode = 400; NotifyListenerContextQuit(a); return; } } { var Query = HttpListenerRequestExtension.GetQuery(a.Request); if (Query.ContainsKey("sessionid")) { HttpSession s = null; var SessionId = Query["sessionid"]; var Close = false; SessionSets.DoAction ( ss => { if (!ss.SessionIdToSession.ContainsKey(SessionId)) { a.Response.StatusCode = 403; Close = true; return; } var CurrentSession = ss.SessionIdToSession[SessionId]; if (!CurrentSession.RemoteEndPoint.Address.Equals(e.Address)) { a.Response.StatusCode = 403; Close = true; return; } s = ss.SessionIdToSession[SessionId]; } ); if (Close) { NotifyListenerContextQuit(a); return; } var NewSessionId = Convert.ToBase64String(Cryptography.CreateRandom(64)); SessionSets.DoAction ( ss => { ss.SessionIdToSession.Remove(SessionId); ss.SessionIdToSession.Add(NewSessionId, s); ss.SessionToId[s] = NewSessionId; } ); if (!s.Push(a, NewSessionId)) { NotifyListenerContextQuit(a); return; } return; } } if (MaxConnectionsValue.HasValue && (SessionSets.Check(ss => ss.Sessions.Count) >= MaxConnectionsValue.Value)) { ContextPurifyConsumer.DoOne(); PurifyConsumer.DoOne(); } if (MaxConnectionsValue.HasValue && (SessionSets.Check(ss => ss.Sessions.Count) >= MaxConnectionsValue.Value)) { a.Response.StatusCode = 503; NotifyListenerContextQuit(a); return; } if (MaxConnectionsPerIPValue.HasValue && (SessionSets.Check(ss => ss.IpSessions.ContainsKey(e.Address) ? ss.IpSessions[e.Address].Count : 0) >= MaxConnectionsPerIPValue.Value)) { a.Response.StatusCode = 503; NotifyListenerContextQuit(a); return; } if (MaxUnauthenticatedPerIPValue.HasValue && (SessionSets.Check(ss => ss.IpSessions.ContainsKey(e.Address) ? (ss.IpSessions[e.Address].Count - ss.IpSessions[e.Address].Authenticated.Count) : 0) >= MaxUnauthenticatedPerIPValue.Value)) { a.Response.StatusCode = 503; NotifyListenerContextQuit(a); return; } { var s = new HttpSession(this, e, VirtualTransportServerFactory, QueueUserWorkItem); var SessionId = Convert.ToBase64String(Cryptography.CreateRandom(64)); SessionSets.DoAction ( ss => { ss.Sessions.Add(s); if (ss.IpSessions.ContainsKey(e.Address)) { ss.IpSessions[e.Address].Count += 1; } else { var isi = new IpSessionInfo(); isi.Count += 1; ss.IpSessions.Add(e.Address, isi); } ss.SessionIdToSession.Add(SessionId, s); ss.SessionToId.Add(s, SessionId); } ); s.Start(); if (!s.Push(a, SessionId)) { NotifyListenerContextQuit(a); return; } } } catch (Exception ex) { if (ServerContext.EnableLogSystem) { ServerContext.RaiseSessionLog(new SessionLogEntry { Token = "", RemoteEndPoint = e ?? new IPEndPoint(IPAddress.Any, 0), Time = DateTime.UtcNow, Type = "Sys", Name = "Exception", Message = ExceptionInfo.GetExceptionInfo(ex) }); } try { a.Response.StatusCode = 500; } catch { } NotifyListenerContextQuit(a); } }; AcceptConsumer = new AsyncConsumer <HttpListenerContext>(QueueUserWorkItem, a => { Accept(a); return(true); }, int.MaxValue); ContextPurifyConsumer = new AsyncConsumer <HttpListenerContext>(QueueUserWorkItem, l => { PurifyContext(l); return(true); }, int.MaxValue); PurifyConsumer = new AsyncConsumer <HttpSession>(PurifierQueueUserWorkItem, s => { Purify(s); return(true); }, int.MaxValue); if (UnauthenticatedSessionIdleTimeoutValue.HasValue || SessionIdleTimeoutValue.HasValue) { var TimePeriod = TimeSpan.FromSeconds(Math.Max(TimeoutCheckPeriodValue, 1)); LastActiveTimeCheckTimer = new Timer(state => { if (UnauthenticatedSessionIdleTimeoutValue.HasValue) { var CheckTime = DateTime.UtcNow.AddIntSeconds(-UnauthenticatedSessionIdleTimeoutValue.Value); SessionSets.DoAction ( ss => { foreach (var s in ss.Sessions) { var IpAddress = s.RemoteEndPoint.Address; var isi = ss.IpSessions[IpAddress]; if (!isi.Authenticated.Contains(s)) { if (s.LastActiveTime < CheckTime) { PurifyConsumer.Push(s); } } } } ); } if (SessionIdleTimeoutValue.HasValue) { var CheckTime = DateTime.UtcNow.AddIntSeconds(-SessionIdleTimeoutValue.Value); SessionSets.DoAction ( ss => { foreach (var s in ss.Sessions) { var IpAddress = s.RemoteEndPoint.Address; var isi = ss.IpSessions[IpAddress]; if (isi.Authenticated.Contains(s)) { if (s.LastActiveTime < CheckTime) { PurifyConsumer.Push(s); } } } } ); } }, null, TimePeriod, TimePeriod); } try { Listener.Start(); } catch (HttpListenerException ex) { String Message; if (ex.ErrorCode == 5) { var l = new List <String>(); l.Add("Under Windows, try run the following as administrator:"); var UserDomainName = Environment.UserDomainName; var UserName = Environment.UserName; foreach (var p in BindingsValue) { l.Add(@"netsh http add urlacl url={0} user={1}\{2}".Formats(p, UserDomainName, UserName)); } l.Add("and delete it when you don't need it:"); foreach (var p in BindingsValue) { l.Add(@"netsh http delete urlacl url={0}".Formats(p)); } Message = String.Join("\r\n", l.ToArray()); } else { Message = ExceptionInfo.GetExceptionInfo(ex); } throw new AggregateException(Message, ex); } Action Listen = () => { if (ListeningTaskToken.IsCancellationRequested) { return; } var l = Listener; var lc = ListenConsumer; l.BeginGetContext(ar => { if (!l.IsListening) { return; } try { var a = l.EndGetContext(ar); AcceptConsumer.Push(a); } catch (HttpListenerException) { } catch (ObjectDisposedException) { } lc.Push(0); }, null); }; ListenConsumer = new AsyncConsumer <int>(QueueUserWorkItem, i => { Listen(); return(true); }, 1); Listen(); Success = true; return(true); } ); } finally { if (!Success) { Stop(); } } }