private static void IPv4_TCPHandler(byte[] packetData)
{
TCP.TCPPacket tcp_packet = new TCP.TCPPacket(packetData);
if (tcp_packet.Syn == true)
{
if (tcpListeners.ContainsKey(tcp_packet.DestinationPort) == true)
{
TCP.TCPConnection connection = new TCP.TCPConnection(tcp_packet.SourceIP, tcp_packet.SourcePort, tcp_packet.DestinationIP,
tcp_packet.DestinationPort, tcp_packet.SequenceNumber, TCP.TCPConnection.State.SYN_RECVD);
tcpSockets.Add(connection);
TCP.TCPPacket syn_ack = new TCP.TCPPacket(connection, connection.LocalSequenceNumber,
++connection.RemoteSequenceNumber, 0x12, 8192, 2);
syn_ack.AddMSSOption(1360);
syn_ack.AddSACKOption();
TCPIP.IPv4OutgoingBuffer.AddPacket(syn_ack);
return;
}
}
TCP.TCPConnection active_connection = null;
for (int c = 0; c < tcpSockets.Count; c++)
{
if ((tcpSockets[c].RemoteIP.CompareTo(tcp_packet.SourceIP) == 0) &&
(tcpSockets[c].RemotePort == tcp_packet.SourcePort) &&
(tcpSockets[c].LocalPort == tcp_packet.DestinationPort))
{
active_connection = tcpSockets[c];
break;
}
}
if (active_connection == null)
{
TCP.TCPPacket reset_packet = new TCP.TCPPacket(tcp_packet.DestinationIP, tcp_packet.SourceIP, tcp_packet.DestinationPort,
tcp_packet.SourcePort, 0, (tcp_packet.SequenceNumber + 1), 0x14, 8192);
TCPIP.IPv4OutgoingBuffer.AddPacket(reset_packet);
return;
}
if (active_connection.ConnectionState == TCP.TCPConnection.State.SYN_RECVD)
{
if ((tcp_packet.Ack == true) && ((active_connection.LocalSequenceNumber + 1) == tcp_packet.AckNumber))
{
active_connection.LocalSequenceNumber++;
active_connection.ConnectionState = TCP.TCPConnection.State.ESTABLISHED;
ClientConnected connectCallback = tcpListeners[tcp_packet.DestinationPort];
connectCallback(new TcpClient(active_connection));
}
}
else if (active_connection.ConnectionState == TCP.TCPConnection.State.SYN_SENT)
{
if ((tcp_packet.Syn == true) && (tcp_packet.Ack == true) && ((active_connection.LocalSequenceNumber + 1) == tcp_packet.AckNumber))
{
active_connection.LocalSequenceNumber++;
active_connection.RemoteSequenceNumber = tcp_packet.SequenceNumber + 1;
active_connection.ConnectionState = TCP.TCPConnection.State.ESTABLISHED;
TCP.TCPPacket ack = new TCP.TCPPacket(active_connection, active_connection.LocalSequenceNumber,
active_connection.RemoteSequenceNumber, 0x10, 8192);
TCPIP.IPv4OutgoingBuffer.AddPacket(ack);
}
}
else if (active_connection.ConnectionState == TCP.TCPConnection.State.ESTABLISHED)
{
if (tcp_packet.Ack == true)
{
//active_connection.LocalSequenceNumber = tcp_packet.AckNumber;
}
if (tcp_packet.TCP_DataLength > 0)
{
active_connection.RemoteSequenceNumber += tcp_packet.TCP_DataLength;
TCP.TCPPacket ack = new TCP.TCPPacket(active_connection, active_connection.LocalSequenceNumber,
active_connection.RemoteSequenceNumber, 0x10, 8192);
TCPIP.IPv4OutgoingBuffer.AddPacket(ack);
active_connection.client.dataReceived(tcp_packet.TCP_Data);
}
if (tcp_packet.Fin == true)
{
active_connection.client.disconnect();
}
}
}
private static void IPv4_TCPHandler(byte[] packetData)
{
TCP.TCPPacket tcp_packet = new TCP.TCPPacket(packetData);
if (tcp_packet.Syn == true)
{
if (tcpListeners.ContainsKey(tcp_packet.DestinationPort) == true)
{
TCP.TCPConnection connection = new TCP.TCPConnection(tcp_packet.SourceIP, tcp_packet.SourcePort, tcp_packet.DestinationIP,
tcp_packet.DestinationPort, tcp_packet.SequenceNumber, TCP.TCPConnection.State.SYN_RECVD);
tcpSockets.Add(connection);
TCP.TCPPacket syn_ack = new TCP.TCPPacket(connection, connection.LocalSequenceNumber,
++connection.RemoteSequenceNumber, 0x12, 8192, 2);
syn_ack.AddMSSOption(1360);
syn_ack.AddSACKOption();
TCPIP.IPv4OutgoingBuffer.AddPacket(syn_ack);
return;
}
}
TCP.TCPConnection active_connection = null;
for (int c = 0; c < tcpSockets.Count; c++)
{
if ((tcpSockets[c].RemoteIP.CompareTo(tcp_packet.SourceIP) == 0) &&
(tcpSockets[c].RemotePort == tcp_packet.SourcePort) &&
(tcpSockets[c].LocalPort == tcp_packet.DestinationPort))
{
active_connection = tcpSockets[c];
break;
}
}
if (active_connection == null)
{
TCP.TCPPacket reset_packet = new TCP.TCPPacket(tcp_packet.DestinationIP, tcp_packet.SourceIP, tcp_packet.DestinationPort,
tcp_packet.SourcePort, 0, (tcp_packet.SequenceNumber + 1), 0x14, 8192);
TCPIP.IPv4OutgoingBuffer.AddPacket(reset_packet);
return;
}
if (active_connection.ConnectionState == TCP.TCPConnection.State.SYN_RECVD)
{
if ((tcp_packet.Ack == true) && ((active_connection.LocalSequenceNumber + 1) == tcp_packet.AckNumber))
{
active_connection.LocalSequenceNumber++;
active_connection.ConnectionState = TCP.TCPConnection.State.ESTABLISHED;
ClientConnected connectCallback = tcpListeners[tcp_packet.DestinationPort];
connectCallback(new TcpClient(active_connection));
}
}
else if (active_connection.ConnectionState == TCP.TCPConnection.State.SYN_SENT)
{
if ((tcp_packet.Syn == true) && (tcp_packet.Ack == true) && ((active_connection.LocalSequenceNumber + 1) == tcp_packet.AckNumber))
{
active_connection.LocalSequenceNumber++;
active_connection.RemoteSequenceNumber = tcp_packet.SequenceNumber + 1;
active_connection.ConnectionState = TCP.TCPConnection.State.ESTABLISHED;
TCP.TCPPacket ack = new TCP.TCPPacket(active_connection, active_connection.LocalSequenceNumber,
active_connection.RemoteSequenceNumber, 0x10, 8192);
TCPIP.IPv4OutgoingBuffer.AddPacket(ack);
}
}
else if (active_connection.ConnectionState == TCP.TCPConnection.State.ESTABLISHED)
{
if (tcp_packet.Ack == true)
{
//active_connection.LocalSequenceNumber = tcp_packet.AckNumber;
}
if (tcp_packet.TCP_DataLength > 0)
{
active_connection.RemoteSequenceNumber += tcp_packet.TCP_DataLength;
TCP.TCPPacket ack = new TCP.TCPPacket(active_connection, active_connection.LocalSequenceNumber,
active_connection.RemoteSequenceNumber, 0x10, 8192);
TCPIP.IPv4OutgoingBuffer.AddPacket(ack);
active_connection.client.dataReceived(tcp_packet.TCP_Data);
}
if (tcp_packet.Fin == true)
{
active_connection.client.disconnect();
}
}
}