//public Packet CreateDhcpPacket(int optionsSize, byte[] options, bool firstPacket, byte[] clientIp = null)
//{
// EthernetLayer ethernetLayer = new EthernetLayer
// {
// Source = ifHardwareAddress,
// Destination = new MacAddress("FF:FF:FF:FF:FF:FF"),
// EtherType = EthernetType.None,
// };
// IpV4Layer ipV4Layer = new IpV4Layer
// {
// Source = new IpV4Address("0.0.0.0"),
// CurrentDestination = new IpV4Address("255.255.255.255"),
// Fragmentation = IpV4Fragmentation.None,
// HeaderChecksum = null, // Will be filled automatically.
// Identification = ipID,
// Options = IpV4Options.None,
// Protocol = null,
// Ttl = 128,
// TypeOfService = 0,
// };
// UdpLayer udpLayer = new UdpLayer
// {
// SourcePort = 68,
// DestinationPort = 67,
// Checksum = null, // Will be filled automatically.
// CalculateChecksumValue = true,
// };
// Dhcp dhcpLayer = new Dhcp(optionsSize);
// if (firstPacket)
// dhcpId = dhcpLayer.Id;
// else
// dhcpLayer.Id = dhcpId;
// if (clientIp != null)
// dhcpLayer.ClientIp = clientIp;
// dhcpLayer.ClientHardwareAddress = ifHardwareAddressByte;
// dhcpLayer.Options = options;
// PayloadLayer payloadLayer = new PayloadLayer
// {
// Data = new Datagram(dhcpLayer.toByteArray()),
// };
// PacketBuilder builder = new PacketBuilder(ethernetLayer, ipV4Layer, udpLayer, payloadLayer);
// return builder.Build(DateTime.Now);
//}
//public void SendArp()
//{
// EthernetLayer ethernetLayer = new EthernetLayer
// {
// Source = ifHardwareAddress,
// Destination = new MacAddress("FF:FF:FF:FF:FF:FF"),
// EtherType = EthernetType.None,
// };
// ArpLayer arpLayer = new ArpLayer
// {
// ProtocolType = EthernetType.IpV4,
// Operation = ArpOperation.Request,
// SenderHardwareAddress = ifHardwareAddressByte.AsReadOnly(),
// SenderProtocolAddress = ownProtocolAddressByte.AsReadOnly(),
// TargetHardwareAddress = new byte[] { 0, 0, 0, 0, 0, 0 }.AsReadOnly(),
// TargetProtocolAddress = gatewayProtocolAddressByte.AsReadOnly(),
// };
// PacketBuilder builder = new PacketBuilder(ethernetLayer, arpLayer);
// SendPacket(builder.Build(DateTime.Now));
//}
//public void ReceiveIpAddress()
//{
// int retries = 0;
// int timewait = 0;
// dhcpState = 0;
// arpState = 0;
// byte[] options;
// while (true)
// {
// if (dhcpState == 1 && retries > 1 ||
// dhcpState == 3 && retries > 1)
// {
// dhcpState = 6;
// offeredIp = BitConverter.GetBytes(ifProtocolAddress.ToValue() & ifProtocolMask.ToValue() + 1).Reverse().ToArray();
// }
// if (dhcpState == 0 || dhcpState == 1 && timewait > 10)
// {
// options = new byte[]
// {
// 53, 1, 1,
// 61, 7, 1, 0x0A, 0x03, 0x03, 0x03, 0x03, (byte)dhcpClientId,
// 12, 4, 78, 77, 76, 66,
// 60, 8, 0x4d, 0x53, 0x46, 0x54, 0x20, 0x35, 0x2e, 0x30,
// 255,
// 0, 0, 0,
// };
// SendPacket(CreateDhcpPacket(32, options, true));
// if (dhcpState == 0)
// retries = 0;
// else
// retries++;
// timewait = 0;
// dhcpState = 1;
// }
// else if (dhcpState == 2 || dhcpState == 3 && timewait > 10)
// {
// options = new byte[]
// {
// 53, 1, 3,
// 61, 7, 1, 0x0A, 0x03, 0x03, 0x03, 0x03, (byte)dhcpClientId,
// 12, 4, 78, 77, 76, 66,
// 50, 4, offeredIp[0], offeredIp[1], offeredIp[2], offeredIp[3],
// 54, 4, dhcpServer[0], dhcpServer[1], dhcpServer[2], dhcpServer[3],
// 60, 8, 0x4d, 0x53, 0x46, 0x54, 0x20, 0x35, 0x2e, 0x30,
// 255,
// 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
// };
// SendPacket(CreateDhcpPacket(60, options, false));
// if (dhcpState == 2)
// retries = 0;
// else
// retries++;
// timewait = 0;
// dhcpState = 3;
// }
// else if (dhcpState == 4 && arpState == 1 && retries > 1)
// {
// if ((BitConverter.ToUInt32(offeredIp.Reverse().ToArray(), 0) + 1 & ifProtocolMask.ToValue()) !=
// (ifProtocolAddress.ToValue() & ifProtocolMask.ToValue()))
// {
// Global.WriteLog("DHCP: IP " + offeredIp.SequenceToString(".") + " is in a different network!");
// offeredIp = BitConverter.GetBytes(ifProtocolAddress.ToValue() & ifProtocolMask.ToValue() + 1).Reverse().ToArray();
// dhcpState = 6;
// arpState = 0;
// continue;
// }
// dhcpState = 5;
// arpState = 0;
// Global.WriteLog("DHCP: IP " + offeredIp.SequenceToString(".") + " OK!");
// dhcpClientId++;
// ownProtocolAddressByte = offeredIp;
// ownProtocolAddressString = ownProtocolAddressByte.SequenceToString(".");
// ownProtocolAddress = new IpV4Address(ownProtocolAddressString);
// SendArp();
// break;
// }
// else if (dhcpState == 4 && arpState == 0 || dhcpState == 4 && arpState == 1 && timewait > 10)
// {
// EthernetLayer ethernetLayer = new EthernetLayer
// {
// Source = ifHardwareAddress,
// Destination = new MacAddress("FF:FF:FF:FF:FF:FF"),
// EtherType = EthernetType.None,
// };
// ArpLayer arpLayer = new ArpLayer
// {
// ProtocolType = EthernetType.IpV4,
// Operation = ArpOperation.Request,
// SenderHardwareAddress = ifHardwareAddressByte.AsReadOnly(),
// SenderProtocolAddress = new byte[] { 0, 0, 0, 0 }.AsReadOnly(),
// TargetHardwareAddress = new byte[] { 0, 0, 0, 0, 0, 0 }.AsReadOnly(),
// TargetProtocolAddress = offeredIp.AsReadOnly(),
// };
// PacketBuilder builder = new PacketBuilder(ethernetLayer, arpLayer);
// SendPacket(builder.Build(DateTime.Now));
// if (arpState == 0)
// retries = 0;
// else
// retries++;
// timewait = 0;
// arpState = 1;
// }
// else if (dhcpState == 4 && arpState == 2)
// {
// Global.WriteLog("DHCP: IP " + offeredIp.SequenceToString(".") + " is already used!");
// options = new byte[]
// {
// 53, 1, 4,
// 61, 7, 1, 0x0A, 0x03, 0x03, 0x03, 0x03, (byte)dhcpClientId,
// 50, 4, offeredIp[0], offeredIp[1], offeredIp[2], offeredIp[3],
// 54, 4, dhcpServer[0], dhcpServer[1], dhcpServer[2], dhcpServer[3],
// 255,
// //0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
// };
// SendPacket(CreateDhcpPacket(25, options, false, offeredIp));
// arpState = 0;
// dhcpState = 0;
// }
// else if (dhcpState == 6 && arpState == 1 && retries > 1)
// {
// dhcpState = 5;
// arpState = 0;
// Global.WriteLog("IPAlloc: IP " + offeredIp.SequenceToString(".") + " OK!");
// dhcpClientId++;
// ownProtocolAddressByte = offeredIp;
// ownProtocolAddressString = ownProtocolAddressByte.SequenceToString(".");
// ownProtocolAddress = new IpV4Address(ownProtocolAddressString);
// SendArp();
// break;
// }
// else if (dhcpState == 6 && arpState == 0 || dhcpState == 6 && arpState == 1 && timewait > 10)
// {
// EthernetLayer ethernetLayer = new EthernetLayer
// {
// Source = ifHardwareAddress,
// Destination = new MacAddress("FF:FF:FF:FF:FF:FF"),
// EtherType = EthernetType.None,
// };
// ArpLayer arpLayer = new ArpLayer
// {
// ProtocolType = EthernetType.IpV4,
// Operation = ArpOperation.Request,
// SenderHardwareAddress = ifHardwareAddressByte.AsReadOnly(),
// SenderProtocolAddress = new byte[] { 0, 0, 0, 0 }.AsReadOnly(),
// TargetHardwareAddress = new byte[] { 0, 0, 0, 0, 0, 0 }.AsReadOnly(),
// TargetProtocolAddress = offeredIp.AsReadOnly(),
// };
// PacketBuilder builder = new PacketBuilder(ethernetLayer, arpLayer);
// SendPacket(builder.Build(DateTime.Now));
// if (arpState == 0)
// retries = 0;
// else
// retries++;
// timewait = 0;
// arpState = 1;
// }
// else if (dhcpState == 6 && arpState == 2)
// {
// if ((BitConverter.ToUInt32(offeredIp.Reverse().ToArray(), 0) + 1 & ifProtocolMask.ToValue()) !=
// (ifProtocolAddress.ToValue() & ifProtocolMask.ToValue()))
// {
// Global.WriteLog("IPAlloc: Couldn't allocate IP address!");
// break;
// }
// Global.WriteLog("IPAlloc: IP " + offeredIp.SequenceToString(".") + " is already used!");
// offeredIp = BitConverter.GetBytes((BitConverter.ToUInt32(offeredIp.Reverse().ToArray(), 0) + 1)).Reverse().ToArray();
// arpState = 0;
// }
// Thread.Sleep(100);
// timewait++;
// }
//}
public void ReceivePackets()
{
// Retrieve the device list from the local machine
IList <LivePacketDevice> allDevices = LivePacketDevice.AllLocalMachine;
// Find the NPF device of the interface
PacketDevice selectedDevice = null;
for (int i = 0; i != allDevices.Count; ++i)
{
LivePacketDevice device = allDevices[i];
if (device.Name.ToUpper().Contains(Guid.ToString().ToUpper()))
{
selectedDevice = device;
break;
}
}
if (selectedDevice == null)
{
Initialized.Set();
Global.ShowTrayTip("Load Balancer", "Interface " + Name + " not captured by WinPcap.", System.Windows.Forms.ToolTipIcon.Warning);
Global.WriteLog("Load Balancer: Interface " + Name + " not captured by WinPcap.");
return;
}
try
{
using (communicator = selectedDevice.Open(65536, PacketDeviceOpenAttributes.MaximumResponsiveness, 1000))
{
Global.WriteLog("Load Balancer: Listening on " + Name + "...");
//communicator.SetFilter("(ether dst " + ifHardwareAddressString + " and (ip or arp)) or (ether dst FF:FF:FF:FF:FF:FF and arp)");
communicator.SetFilter("(ether dst " + ifHardwareAddressString + " and ip and (udp or icmp))");
Initialized.Set();
communicator.ReceivePackets(0, (packet) =>
{
if (!ThreadActive.IsSet)
{
communicator.Break();
return;
}
//if (ownProtocolAddressString == null)
//{
// if (packet.Ethernet.IpV4.Udp.SourcePort == 67 && packet.Ethernet.IpV4.Udp.DestinationPort == 68 && (PublicVars.dhcpState == 1 || PublicVars.dhcpState == 3))
// {
// Dhcp dhcpReply = new Dhcp(packet.Ethernet.IpV4.Udp.Payload.ToArray());
// if (PublicVars.dhcpId == dhcpReply.Id && dhcpReply.MessageType == 2)
// {
// if (dhcpReply.getOption((int)DhcpOptionCode.DhcpMsgType)[0] == 2)
// {
// PublicVars.offeredIp = dhcpReply.YourIp;
// PublicVars.dhcpServer = dhcpReply.getOption((int)DhcpOptionCode.DhcpServerId);
// PublicVars.dhcpState = 2;
// }
// else if (dhcpReply.getOption((int)DhcpOptionCode.DhcpMsgType)[0] == 5)
// {
// PublicVars.dhcpState = 4;
// }
// else if (dhcpReply.getOption((int)DhcpOptionCode.DhcpMsgType)[0] == 6)
// {
// PublicVars.offeredIp = null;
// PublicVars.dhcpState = 0;
// PublicVars.dhcpId = 0;
// }
// }
// }
// else if (packet.Ethernet.EtherType == EthernetType.Arp && PublicVars.arpState == 1)
// {
// if (packet.Ethernet.Arp.SenderProtocolAddress.SequenceEqual(PublicVars.offeredIp))
// PublicVars.arpState = 2;
// }
//}
//if (packet.Ethernet.EtherType == EthernetType.Arp)
//{
// if (packet.Ethernet.Arp.TargetProtocolAddress.SequenceEqual(ownProtocolAddressByte) &&
// packet.Ethernet.Arp.Operation == ArpOperation.Request)
// {
// EthernetLayer ethernetLayer = new EthernetLayer
// {
// Source = ifHardwareAddress,
// Destination = packet.Ethernet.Source,
// EtherType = EthernetType.None,
// };
// ArpLayer arpLayer = new ArpLayer
// {
// ProtocolType = EthernetType.IpV4,
// Operation = ArpOperation.Reply,
// SenderHardwareAddress = ifHardwareAddressByte.AsReadOnly(),
// SenderProtocolAddress = packet.Ethernet.Arp.TargetProtocolAddress,
// TargetHardwareAddress = packet.Ethernet.Arp.SenderHardwareAddress,
// TargetProtocolAddress = packet.Ethernet.Arp.SenderProtocolAddress,
// };
// PacketBuilder builder = new PacketBuilder(ethernetLayer, arpLayer);
// communicator.SendPacket(builder.Build(DateTime.Now));
// }
//}
if (tapWorker.Initialized.IsSet)
{
if (packet.Ethernet.IpV4.Length > MTU) // only UDP and ICMP
{
EthernetLayer ethernetLayer = new EthernetLayer
{
Source = ifHardwareAddress,
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.Fragmentation.Options == IpV4FragmentationOptions.DoNotFragment ||
packet.Ethernet.IpV4.Fragmentation.Options == IpV4FragmentationOptions.None && packet.Ethernet.IpV4.Fragmentation.Offset == 0)
{
if (packet.Ethernet.IpV4.Protocol == IpV4Protocol.InternetControlMessageProtocol)
{
if (packet.Ethernet.IpV4.Destination == ifProtocolAddress)
{
if ((packet.Ethernet.IpV4.Icmp.MessageType == IcmpMessageType.EchoReply || packet.Ethernet.IpV4.Fragmentation.Offset > 0))
{
EthernetLayer ethernetLayer = new EthernetLayer
{
Source = tapWorker.ownHardwareAddress,
Destination = tapWorker.ifHardwareAddress,
EtherType = EthernetType.None,
};
IpV4Layer ipV4Layer = new IpV4Layer
{
Source = packet.Ethernet.IpV4.Source,
CurrentDestination = tapWorker.ifProtocolAddress,
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 = packet.Ethernet.IpV4.Ttl,
TypeOfService = packet.Ethernet.IpV4.TypeOfService,
};
PayloadLayer payloadLayer = new PayloadLayer
{
Data = new Datagram(packet.Ethernet.IpV4.Payload.ToArray()),
};
PacketBuilder builder = new PacketBuilder(ethernetLayer, ipV4Layer, payloadLayer);
tapWorker.SendPacket(builder.Build(DateTime.Now));
}
}
}
//else if (packet.Ethernet.IpV4.Protocol == IpV4Protocol.Tcp)
//{
// if (packet.Ethernet.IpV4.Destination == ifProtocolAddress)
// {
// lock (RoutingTable.lockObj)
// routingObject = RoutingTable.TranslateBack(packet);
// if (routingObject.ifIndex == -1)
// return;
// EthernetLayer ethernetLayer = new EthernetLayer
// {
// Source = TapWorker.ownHardwareAddress,
// Destination = TapWorker.ifHardwareAddress,
// EtherType = packet.Ethernet.EtherType,
// };
// IpV4Layer ipV4Layer = new IpV4Layer
// {
// Source = packet.Ethernet.IpV4.Source,
// CurrentDestination = TapWorker.ifProtocolAddress,
// 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 = packet.Ethernet.IpV4.Ttl,
// TypeOfService = packet.Ethernet.IpV4.TypeOfService,
// };
// TcpLayer tcpLayer = new TcpLayer
// {
// SourcePort = packet.Ethernet.IpV4.Tcp.SourcePort,
// DestinationPort = routingObject.localPort,
// Checksum = null, // Will be filled automatically.
// SequenceNumber = packet.Ethernet.IpV4.Tcp.SequenceNumber,
// AcknowledgmentNumber = routingObject.ack,
// ControlBits = packet.Ethernet.IpV4.Tcp.ControlBits,
// Window = packet.Ethernet.IpV4.Tcp.Window,
// UrgentPointer = packet.Ethernet.IpV4.Tcp.UrgentPointer,
// Options = packet.Ethernet.IpV4.Tcp.Options,
// };
// PayloadLayer payloadLayer = new PayloadLayer
// {
// Data = new Datagram(packet.Ethernet.IpV4.Tcp.Payload.ToArray()),
// };
// PacketBuilder builder = new PacketBuilder(ethernetLayer, ipV4Layer, tcpLayer, payloadLayer);
// MainThread.tapWorker.SendPacket(builder.Build(DateTime.Now));
// }
//}
else if (packet.Ethernet.IpV4.Protocol == IpV4Protocol.Udp)
{
if (packet.Ethernet.IpV4.Destination == ifProtocolAddress)
{
phyRoutingObject = RoutingTable.IsUdpConn(packet);
if (phyRoutingObject.ifIndex == -1)
{
return;
}
EthernetLayer ethernetLayer = new EthernetLayer
{
Source = tapWorker.ownHardwareAddress,
Destination = tapWorker.ifHardwareAddress,
EtherType = packet.Ethernet.EtherType,
};
IpV4Layer ipV4Layer = new IpV4Layer
{
Source = packet.Ethernet.IpV4.Source,
CurrentDestination = tapWorker.ifProtocolAddress,
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 = packet.Ethernet.IpV4.Ttl,
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);
tapWorker.SendPacket(builder.Build(DateTime.Now));
}
}
}
else if (packet.Ethernet.IpV4.Fragmentation.Options == IpV4FragmentationOptions.MoreFragments ||
packet.Ethernet.IpV4.Fragmentation.Options == IpV4FragmentationOptions.None && packet.Ethernet.IpV4.Fragmentation.Offset > 0)
{
// TODO: fix warning spam
if (Global.Config.LoadBalancer.ShowTrayTipsWarnings)
{
Global.ShowTrayTip("Load Balancer", "IP fragmentation detected on " + Name + ".\n\nIP fragmentation is not supported.", ToolTipIcon.Warning);
}
Global.WriteLog("Load Balancer: IP fragmentation detected on " + Name);
//fragments = fragBuffer.Add(packet);
//if (fragments != null)
// for (int i = 0; i < fragments.Count; i++)
// {
// IpV4Handler(fragments[i], fragments);
// }
}
}
});
}
}
catch (Exception e)
{
if (ThreadActive.IsSet)
{
ThreadActive.Reset();
Global.WriteLog("Load Balancer: " + Name + " has disconnected");
if (Global.Config.Gadget.Debug)
{
Global.WriteLog(e.ToString());
}
Global.ShowTrayTip("Load Balancer", Name + " has disconnected", System.Windows.Forms.ToolTipIcon.Warning);
}
}
}
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));
}
}
}