Beispiel #1
0
        public override ILayer ExtractLayer()
        {
            IcmpTimeExceededLayer timeExceededLayer = new IcmpTimeExceededLayer();

            timeExceededLayer.Code     = (IcmpCodeTimeExceeded)this.Code;
            timeExceededLayer.Checksum = new ushort?(this.Checksum);
            return((ILayer)timeExceededLayer);
        }
Beispiel #2
0
            public void IpV4Handler(Packet packet, IList<Packet> packetList = null)
            {
                if (packet.Ethernet.IpV4.Length > MTU)
                {
                    EthernetLayer ethernetLayer = new EthernetLayer
                    {
                        Source = ownHardwareAddress,
                        Destination = packet.Ethernet.Source,
                        EtherType = EthernetType.None,
                    };
                    IpV4Layer ipV4Layer = new IpV4Layer
                    {
                        Source = packet.Ethernet.IpV4.Destination,
                        CurrentDestination = packet.Ethernet.IpV4.Source,
                        Fragmentation = packet.Ethernet.IpV4.Fragmentation,
                        HeaderChecksum = null, // Will be filled automatically.
                        Identification = 123,
                        Options = packet.Ethernet.IpV4.Options,
                        Protocol = packet.Ethernet.IpV4.Protocol,
                        Ttl = packet.Ethernet.IpV4.Ttl,
                        TypeOfService = packet.Ethernet.IpV4.TypeOfService,
                    };
                    IcmpDestinationUnreachableLayer icmpLayer = new IcmpDestinationUnreachableLayer
                    {
                        Code = IcmpCodeDestinationUnreachable.FragmentationNeededAndDoNotFragmentSet,
                        NextHopMaximumTransmissionUnit = (ushort)MTU,
                    };

                    PacketBuilder builder = new PacketBuilder(ethernetLayer, ipV4Layer, icmpLayer);
                    SendPacket(builder.Build(DateTime.Now));
                    // TODO: fix warning spam
                    if (Global.Config.LoadBalancer.ShowTrayTipsWarnings)
                        Global.ShowTrayTip("Load Balancer", "IP packet larger than the MTU detected on " + Name + ".\n\nIP fragmentation is not supported.", ToolTipIcon.Warning);
                    Global.WriteLog("Load Balancer: IP packet larger than the MTU detected on " + Name);
                    return;
                }
                if (packet.Ethernet.IpV4.Ttl < 2)
                {
                    EthernetLayer ethernetLayer = new EthernetLayer
                    {
                        Source = ownHardwareAddress,
                        Destination = packet.Ethernet.Source,
                        EtherType = EthernetType.None,
                    };
                    IpV4Layer ipV4Layer = new IpV4Layer
                    {
                        Source = ownProtocolAddress,
                        CurrentDestination = packet.Ethernet.IpV4.Source,
                        Fragmentation = packet.Ethernet.IpV4.Fragmentation,
                        HeaderChecksum = null, // Will be filled automatically.
                        Identification = 123,
                        Options = packet.Ethernet.IpV4.Options,
                        Protocol = packet.Ethernet.IpV4.Protocol,
                        Ttl = packet.Ethernet.IpV4.Ttl,
                        TypeOfService = packet.Ethernet.IpV4.TypeOfService,
                    };
                    IcmpTimeExceededLayer icmpLayer = new IcmpTimeExceededLayer
                    {
                        Code = 0,
                    };

                    PacketBuilder builder = new PacketBuilder(ethernetLayer, ipV4Layer, icmpLayer, packet.Ethernet.IpV4.ExtractLayer(), packet.Ethernet.IpV4.Payload.ExtractLayer());
                    SendPacket(builder.Build(DateTime.Now));
                    return;
                }
                if (packet.Ethernet.IpV4.Protocol == IpV4Protocol.InternetControlMessageProtocol)
                {
                    if (packet.Ethernet.IpV4.Destination == ownProtocolAddress)
                    {
                        if ((packet.Ethernet.IpV4.Icmp.MessageType == IcmpMessageType.Echo || packet.Ethernet.IpV4.Fragmentation.Offset > 0))
                        {
                            EthernetLayer ethernetLayer = new EthernetLayer
                            {
                                Source = ownHardwareAddress,
                                Destination = packet.Ethernet.Source,
                                EtherType = EthernetType.None,
                            };
                            IpV4Layer ipV4Layer = new IpV4Layer
                            {
                                Source = packet.Ethernet.IpV4.Destination,
                                CurrentDestination = packet.Ethernet.IpV4.Source,
                                Fragmentation = packet.Ethernet.IpV4.Fragmentation,
                                HeaderChecksum = null, // Will be filled automatically.
                                Identification = 123,
                                Options = packet.Ethernet.IpV4.Options,
                                Protocol = packet.Ethernet.IpV4.Protocol,
                                Ttl = packet.Ethernet.IpV4.Ttl,
                                TypeOfService = packet.Ethernet.IpV4.TypeOfService,
                            };
                            if (packet.Ethernet.IpV4.Fragmentation.Options == IpV4FragmentationOptions.DoNotFragment ||
                                packet.Ethernet.IpV4.Fragmentation.Options == IpV4FragmentationOptions.None && packet.Ethernet.IpV4.Fragmentation.Offset == 0)
                            {
                                byte[] icmpPacket = packet.Ethernet.IpV4.Payload.ToArray();
                                icmpPacket[0] = 0;
                                icmpPacket[2] = 0;
                                icmpPacket[3] = 0;
                                ushort checksum = IpFunctions.ComputeIpChecksum(icmpPacket);
                                icmpPacket[2] = (byte)(checksum >> 8);
                                icmpPacket[3] = (byte)(checksum & 0xff);
                                PayloadLayer payloadLayer = new PayloadLayer
                                {
                                    Data = new Datagram(icmpPacket),
                                };
                                PacketBuilder builder = new PacketBuilder(ethernetLayer, ipV4Layer, payloadLayer);
                                SendPacket(builder.Build(DateTime.Now));
                            }
                            else if (packet.Ethernet.IpV4.Fragmentation.Offset == 0 && packet.Ethernet.IpV4.Fragmentation.Options == IpV4FragmentationOptions.MoreFragments)
                            {
                                byte[] icmpHeader = packet.Ethernet.IpV4.Payload.ToArray();
                                icmpHeader[0] = 0;
                                icmpHeader[2] = 0;
                                icmpHeader[3] = 0;
                                int icmpPacketLength = icmpHeader.Length;
                                for (int i = 1; i < packetList.Count; i++)
                                {
                                    icmpPacketLength += packetList[i].Ethernet.IpV4.Payload.ToArray().Length;
                                }
                                byte[] icmpPacket = new byte[icmpPacketLength];
                                Buffer.BlockCopy(icmpHeader, 0, icmpPacket, 0, icmpHeader.Length);
                                icmpPacketLength = icmpHeader.Length;
                                for (int i = 1; i < packetList.Count; i++)
                                {
                                    Buffer.BlockCopy(packetList[i].Ethernet.IpV4.Payload.ToArray(), 0, icmpPacket, icmpPacketLength, packetList[i].Ethernet.IpV4.Payload.ToArray().Length);
                                    icmpPacketLength += packetList[i].Ethernet.IpV4.Payload.ToArray().Length;
                                }
                                ushort checksum = IpFunctions.ComputeIpChecksum(icmpPacket);
                                icmpHeader[2] = (byte)(checksum >> 8);
                                icmpHeader[3] = (byte)(checksum & 0xff);
                                PayloadLayer payloadLayer = new PayloadLayer
                                {
                                    Data = new Datagram(icmpHeader),
                                };
                                PacketBuilder builder = new PacketBuilder(ethernetLayer, ipV4Layer, payloadLayer);
                                SendPacket(builder.Build(DateTime.Now));
                            }
                            else
                            {
                                PayloadLayer payloadLayer = new PayloadLayer
                                {
                                    Data = new Datagram(packet.Ethernet.IpV4.Payload.ToArray()),
                                };
                                PacketBuilder builder = new PacketBuilder(ethernetLayer, ipV4Layer, payloadLayer);
                                SendPacket(builder.Build(DateTime.Now));
                            }
                        }
                    }
                    else if (packet.Ethernet.IpV4.Source == ifProtocolAddress)
                        if ((packet.Ethernet.IpV4.Icmp.MessageType == IcmpMessageType.Echo || packet.Ethernet.IpV4.Fragmentation.Offset > 0))
                        {
                            {
                                tapRoutingObject = RoutingTable.GetInterface(packet);
                                if (tapRoutingObject.response == -1)
                                    return;
                                EthernetLayer ethernetLayer = new EthernetLayer
                                {
                                    Source = physicalWorkers[tapRoutingObject.ifIndex].ifHardwareAddress,
                                    Destination = physicalWorkers[tapRoutingObject.ifIndex].gatewayHardwareAddress,
                                    EtherType = EthernetType.None,
                                };
                                IpV4Layer ipV4Layer = new IpV4Layer
                                {
                                    Source = physicalWorkers[tapRoutingObject.ifIndex].ifProtocolAddress,
                                    CurrentDestination = packet.Ethernet.IpV4.Destination,
                                    Fragmentation = packet.Ethernet.IpV4.Fragmentation,
                                    HeaderChecksum = null, // Will be filled automatically.
                                    Identification = packet.Ethernet.IpV4.Identification,
                                    Options = packet.Ethernet.IpV4.Options,
                                    Protocol = packet.Ethernet.IpV4.Protocol,
                                    Ttl = (byte)(packet.Ethernet.IpV4.Ttl - 1),
                                    TypeOfService = packet.Ethernet.IpV4.TypeOfService,
                                };
                                PayloadLayer payloadLayer = new PayloadLayer
                                {
                                    Data = new Datagram(packet.Ethernet.IpV4.Payload.ToArray()),
                                };
                                PacketBuilder builder = new PacketBuilder(ethernetLayer, ipV4Layer, payloadLayer);
                                physicalWorkers[tapRoutingObject.ifIndex].SendPacket(builder.Build(DateTime.Now));
                            }
                        }
                }
                else if (packet.Ethernet.IpV4.Protocol == IpV4Protocol.Tcp)
                {
                    if (packet.Ethernet.IpV4.Source == ifProtocolAddress)
                    {
                        tapRoutingObject = RoutingTable.GetInterface(packet);
                        if (tapRoutingObject.response == -1)
                            return;
                        if (tapRoutingObject.response == -3)
                        {
                            lock (RoutingTable.connParams[tapRoutingObject.guid])
                                SendAck(tapRoutingObject.guid);
                            return;
                        }
                        lock (RoutingTable.connParams[tapRoutingObject.guid])
                        {
                            RoutingTable.connParams[tapRoutingObject.guid].freeWindow = (int)((packet.Ethernet.IpV4.Tcp.Window << RoutingTable.connParams[tapRoutingObject.guid].windowScale) - (RoutingTable.connParams[tapRoutingObject.guid].seq - packet.Ethernet.IpV4.Tcp.AcknowledgmentNumber));
                            if (RoutingTable.connParams[tapRoutingObject.guid].windowFull)
                            {
                                if (RoutingTable.connParams[tapRoutingObject.guid].freeWindow > RoutingTable.connParams[tapRoutingObject.guid].bytesReceived)
                                {
                                    SendData(tapRoutingObject.guid, RoutingTable.connParams[tapRoutingObject.guid].bytesReceived);
                                    RoutingTable.connParams[tapRoutingObject.guid].freeWindow -= RoutingTable.connParams[tapRoutingObject.guid].bytesReceived;
                                    RoutingTable.connParams[tapRoutingObject.guid].windowFull = false;
                                    RoutingTable.connParams[tapRoutingObject.guid].UpdateSeq(RoutingTable.connParams[tapRoutingObject.guid].bytesReceived);
                                    try
                                    {
                                        RoutingTable.connParams[tapRoutingObject.guid].socket.BeginReceive(RoutingTable.connParams[tapRoutingObject.guid].receivingBuffer, 0, RoutingTable.connParams[tapRoutingObject.guid].receivingBuffer.Count(), 0, new AsyncCallback(physicalWorkers[tapRoutingObject.ifIndex].ReceiveCallback), tapRoutingObject.guid);
                                    }
                                    catch (Exception)
                                    {
                                        RoutingTable.RequestAccess();
                                        if (!RoutingTable.connStatus[tapRoutingObject.guid].remoteEPFin)
                                            tapWorker.SendRst(tapRoutingObject.guid);
                                        RoutingTable.connStatus[tapRoutingObject.guid].remoteEPFin = true;
                                        RoutingTable.connStatus[tapRoutingObject.guid].localEPFin = true;
                                        RoutingTable.ReleaseAccess();
                                    }
                                }
                            }
                        }
                        if (packet.Ethernet.IpV4.Tcp.PayloadLength > 0 || tapRoutingObject.response == -2)
                            physicalWorkers[tapRoutingObject.ifIndex].SendData(packet, tapRoutingObject.guid);
                    }
                }
                else if (packet.Ethernet.IpV4.Protocol == IpV4Protocol.Udp)
                {
                    if (packet.Ethernet.IpV4.Source == ifProtocolAddress)
                    {
                        tapRoutingObject = RoutingTable.GetInterface(packet);
                        if (tapRoutingObject.response == -1)
                            return;
                        EthernetLayer ethernetLayer = new EthernetLayer
                        {
                            Source = physicalWorkers[tapRoutingObject.ifIndex].ifHardwareAddress,
                            Destination = physicalWorkers[tapRoutingObject.ifIndex].gatewayHardwareAddress,
                            EtherType = packet.Ethernet.EtherType,
                        };

                        IpV4Layer ipV4Layer = new IpV4Layer
                        {
                            Source = physicalWorkers[tapRoutingObject.ifIndex].ifProtocolAddress,
                            CurrentDestination = packet.Ethernet.IpV4.Destination,
                            Fragmentation = packet.Ethernet.IpV4.Fragmentation,
                            HeaderChecksum = null, // Will be filled automatically.
                            Identification = packet.Ethernet.IpV4.Identification,
                            Options = packet.Ethernet.IpV4.Options,
                            Protocol = packet.Ethernet.IpV4.Protocol,
                            Ttl = (byte)(packet.Ethernet.IpV4.Ttl - 1),
                            TypeOfService = packet.Ethernet.IpV4.TypeOfService,
                        };
                        UdpLayer udpLayer = new UdpLayer
                        {
                            SourcePort = packet.Ethernet.IpV4.Udp.SourcePort,
                            DestinationPort = packet.Ethernet.IpV4.Udp.DestinationPort,
                            Checksum = null, // Will be filled automatically.
                            CalculateChecksumValue = packet.Ethernet.IpV4.Udp.IsChecksumOptional,
                        };
                        PayloadLayer payloadLayer = new PayloadLayer
                        {
                            Data = new Datagram(packet.Ethernet.IpV4.Udp.Payload.ToArray()),
                        };
                        PacketBuilder builder = new PacketBuilder(ethernetLayer, ipV4Layer, udpLayer, payloadLayer);
                        physicalWorkers[tapRoutingObject.ifIndex].SendPacket(builder.Build(DateTime.Now));
                    }

                }
            }