private static void HandleTcp(Packet packet, int threadID)
{
TcpLayer tcpLayer = (TcpLayer)packet.Ethernet.IpV4.Tcp.ExtractLayer();
MyDevice newDev = GetDevice(threadID, "other");
IpV4Layer ipLayer = (IpV4Layer)packet.Ethernet.IpV4.ExtractLayer();
PayloadLayer tcpPayload = (PayloadLayer)packet.Ethernet.IpV4.Tcp.Payload.ExtractLayer();
TcpSessionKey tcpKey1 = new TcpSessionKey(ipLayer.Source.ToString(), tcpLayer.SourcePort, ipLayer.Destination.ToString(), tcpLayer.DestinationPort);
TcpSessionKey tcpKey2 = new TcpSessionKey(ipLayer.Destination.ToString(), tcpLayer.DestinationPort, ipLayer.Source.ToString(), tcpLayer.SourcePort);
bool newSession = false;
TcpSessionValue currentSession = null;
try
{
currentSession = sessionDic[tcpKey1];
}
catch
{
try
{
currentSession = sessionDic[tcpKey2];
}
catch
{
newSession = true;
TcpSessionKey tcpKeyN = new TcpSessionKey(ipLayer.Source.ToString(), tcpLayer.SourcePort, ipLayer.Destination.ToString(), tcpLayer.DestinationPort);
TcpSessionValue tcpValueN = new TcpSessionValue(tcpLayer.SequenceNumber, tcpLayer.AcknowledgmentNumber, 64000, tcpLayer.SequenceNumber);
currentSession = tcpValueN;
sessionDic.Add(tcpKeyN, tcpValueN);
}
}
if (!newSession)
{
int prevAckNum = (int)currentSession.ackNum;
int prevSeqNum = (int)currentSession.seqNum;
int curAckNum = (int)tcpLayer.AcknowledgmentNumber;
int curSeqNum = (int)tcpLayer.SequenceNumber;
int oldSeqNum = (int)currentSession.prevseq;
if (curSeqNum - oldSeqNum < currentSession.windowSize && curSeqNum - oldSeqNum >= 0 && (curSeqNum == prevSeqNum || curAckNum == prevSeqNum))
{
currentSession.prevseq = currentSession.seqNum;
currentSession.ackNum = tcpLayer.AcknowledgmentNumber;
currentSession.seqNum = tcpLayer.SequenceNumber;
Packet newPacket = null;
string targetMac = null;
targetMac = GetTargetAddress(packet, newDev).Mac;
if (targetMac != null)
{
newPacket = BuildTcpPacket(new MacAddress(newDev.MacAddressWithDots()), new MacAddress(targetMac), ipLayer, tcpLayer, tcpPayload);
}
else
{
Console.WriteLine("No target MAC found");
}
Console.WriteLine("packet built");
if (newPacket.IsValid)
{
Console.WriteLine("TCP packet sent");
newDev.Communicator.SendPacket(newPacket);
}
else
{
Console.WriteLine("Packet not valid");
}
}
else
{
Console.WriteLine("TCP packet not valid");
}
}
}
private static void HandleTcp(Packet packet, int threadID)
{
TcpLayer tcpLayer = (TcpLayer)packet.Ethernet.IpV4.Tcp.ExtractLayer();
MyDevice newDev = GetDevice(threadID, "other");
IpV4Layer ipLayer = (IpV4Layer)packet.Ethernet.IpV4.ExtractLayer();
PayloadLayer tcpPayload = (PayloadLayer)packet.Ethernet.IpV4.Tcp.Payload.ExtractLayer();
TcpSessionKey tcpKey1 = new TcpSessionKey(ipLayer.Source.ToString(), tcpLayer.SourcePort, ipLayer.Destination.ToString(), tcpLayer.DestinationPort);
TcpSessionKey tcpKey2 = new TcpSessionKey(ipLayer.Destination.ToString(), tcpLayer.DestinationPort, ipLayer.Source.ToString(), tcpLayer.SourcePort);
bool newSession = false;
TcpSessionValue currentSession = null;
try
{
currentSession = sessionDic[tcpKey1];
}
catch
{
try
{
currentSession = sessionDic[tcpKey2];
}
catch
{
newSession = true;
TcpSessionKey tcpKeyN = new TcpSessionKey(ipLayer.Source.ToString(), tcpLayer.SourcePort, ipLayer.Destination.ToString(), tcpLayer.DestinationPort);
TcpSessionValue tcpValueN = new TcpSessionValue(tcpLayer.SequenceNumber, tcpLayer.AcknowledgmentNumber, 64000, tcpLayer.SequenceNumber);
currentSession = tcpValueN;
sessionDic.Add(tcpKeyN, tcpValueN);
}
}
if (!newSession)
{
int prevAckNum = (int)currentSession.ackNum;
int prevSeqNum = (int)currentSession.seqNum;
int curAckNum = (int)tcpLayer.AcknowledgmentNumber;
int curSeqNum = (int)tcpLayer.SequenceNumber;
int oldSeqNum = (int)currentSession.prevseq;
if (curSeqNum - oldSeqNum < currentSession.windowSize && curSeqNum - oldSeqNum >= 0 && (curSeqNum == prevSeqNum || curAckNum == prevSeqNum))
{
currentSession.prevseq = currentSession.seqNum;
currentSession.ackNum = tcpLayer.AcknowledgmentNumber;
currentSession.seqNum = tcpLayer.SequenceNumber;
Packet newPacket = null;
string targetMac = null;
targetMac = GetTargetAddress(packet, newDev).Mac;
if (targetMac != null)
{
newPacket = BuildTcpPacket(new MacAddress(newDev.MacAddressWithDots()), new MacAddress(targetMac), ipLayer, tcpLayer, tcpPayload);
}
else
{
Console.WriteLine("No target MAC found");
}
Console.WriteLine("packet built");
if (newPacket.IsValid)
{
Console.WriteLine("TCP packet sent");
newDev.Communicator.SendPacket(newPacket);
}
else
{
Console.WriteLine("Packet not valid");
}
}
else
{
Console.WriteLine("TCP packet not valid");
}
}
}