public TcpClient(IPv4Address dest, UInt16 port)
{
IPv4Address source = TCPIPStack.FindNetwork(dest);
if( source == null )
{
throw new ArgumentException("Destination host unreachable", "dest");
}
this.connection = new TCPConnection(dest, port, source, NextLocalPort++, 0x5656, TCPConnection.State.SYN_SENT);
this.connection.client = this;
TCPIPStack.tcpSockets.Add(connection);
TCPPacket packet = new TCPPacket(connection, connection.LocalSequenceNumber, 0, 0x02, 8192);
TCPIP.IPv4OutgoingBuffer.AddPacket(packet);
}
/// <summary>
/// Send a raw byte buffer to the remote host
/// </summary>
/// <param name="data">Byte buffer with data to send</param>
public void SendData(byte[] data)
{
if (data.Length < mss)
{
TCPPacket packet = new TCPPacket(connection.LocalIP, connection.RemoteIP, connection.LocalPort, connection.RemotePort,
connection.LocalSequenceNumber, connection.RemoteSequenceNumber, 0x18, 8192, data);
TCPIP.IPv4OutgoingBuffer.AddPacket(packet);
connection.LocalSequenceNumber += (uint)data.Length;
return;
}
int remaining_bytes = data.Length;
int data_idx = 0;
byte[] new_buffer;
byte tcp_flags = 0x10;
while (remaining_bytes > 0)
{
if (remaining_bytes > mss)
{
new_buffer = new byte[mss];
}
else
{
new_buffer = new byte[remaining_bytes];
tcp_flags = 0x18;
}
for (int b = 0; b < new_buffer.Length; b++)
{
new_buffer[b] = data[data_idx];
data_idx++;
remaining_bytes--;
}
TCPPacket packet = new TCPPacket(connection.LocalIP, connection.RemoteIP, connection.LocalPort, connection.RemotePort,
connection.LocalSequenceNumber, connection.RemoteSequenceNumber, tcp_flags, 8192, new_buffer);
TCPIP.IPv4OutgoingBuffer.AddPacket(packet);
connection.LocalSequenceNumber += (uint)new_buffer.Length;
}
}
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();
}
}
}
/// <summary>
/// Close down an active connection
/// </summary>
public void Close()
{
TCPPacket packet = new TCPPacket(connection, connection.LocalSequenceNumber, connection.RemoteSequenceNumber + 1, 0x11, 8192);
TCPIP.IPv4OutgoingBuffer.AddPacket(packet);
connection.ConnectionState = TCPConnection.State.TIMEWAIT;
}
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();
}
}
}
