public override void OnCommand(ITFtpCommand command, System.Net.EndPoint endpoint)
{
switch (command)
{
case OptionAcknowledgement optionAcknowledgement:
{
TransferOptionSet acknowledged = new TransferOptionSet(optionAcknowledgement.Options);
Context.FinishOptionNegotiation(acknowledged);
BeginSendingTo(endpoint);
break;
}
case Acknowledgement acknowledgement when acknowledgement.BlockNumber == 0:
Context.FinishOptionNegotiation(TransferOptionSet.NewEmptySet());
BeginSendingTo(endpoint);
break;
case Error error:
// The server denied our request
Context.SetState(new ReceivedError(error));
break;
default:
base.OnCommand(command, endpoint);
break;
}
}
private void Connection_OnCommandReceived(ITFtpCommand command, EndPoint endpoint)
{
lock (this)
{
State.OnCommand(command, endpoint);
}
}
private void ServerSocket_OnCommandReceived(ITFtpCommand command, EndPoint endpoint)
{
// Ignore all other commands
if (!(command is ReadOrWriteRequest))
{
return;
}
// Open a connection to the client
ITransferChannel channel = TransferChannelFactory.CreateConnection(endpoint);
// Create a wrapper for the transfer request
ReadOrWriteRequest request = (ReadOrWriteRequest)command;
ITFtpTransfer transfer = request is ReadRequest ? (ITFtpTransfer) new LocalReadTransfer(channel, request.Filename, request.Options) : new LocalWriteTransfer(channel, request.Filename, request.Options);
switch (command)
{
case ReadRequest _:
RaiseOnReadRequest(transfer, endpoint);
break;
case WriteRequest _:
RaiseOnWriteRequest(transfer, endpoint);
break;
default:
throw new Exception($"Unexpected TFTP transfer request: {command}");
}
}
public override void OnCommand(ITFtpCommand command, EndPoint endpoint)
{
if (!endpoint.Equals(Context.GetConnection().RemoteEndpoint))
{
throw new Exception($"Received message from illegal endpoint. Actual: {endpoint}. Expected: {Context.GetConnection().RemoteEndpoint}");
}
command.Visit(this);
}
public override void OnCommand(ITFtpCommand command, EndPoint endpoint)
{
if (command is Commands.Data || command is OptionAcknowledgement)
{
// The server acknowledged our read request.
// Fix out remote endpoint
Context.GetConnection().RemoteEndpoint = endpoint;
}
switch (command)
{
case Commands.Data _:
{
if (Context.NegotiatedOptions == null)
{
Context.FinishOptionNegotiation(TransferOptionSet.NewEmptySet());
}
// Switch to the receiving state...
ITransferState nextState = new Receiving();
Context.SetState(nextState);
// ...and let it handle the data packet
nextState.OnCommand(command, endpoint);
break;
}
case OptionAcknowledgement optionAcknowledgement:
// Check which options were acknowledged
Context.FinishOptionNegotiation(new TransferOptionSet(optionAcknowledgement.Options));
// the server acknowledged our options. Confirm the final options
SendAndRepeat(new Acknowledgement(0));
break;
case Error error:
Context.SetState(new ReceivedError(error));
break;
default:
base.OnCommand(command, endpoint);
break;
}
}
public void Send(ITFtpCommand command)
{
if (m_client == null)
{
throw new ObjectDisposedException(nameof(UdpChannel));
}
if (m_endpoint == null)
{
throw new InvalidOperationException("RemoteEndpoint needs to be set before you can send TFTP commands.");
}
using (MemoryStream stream = new MemoryStream())
{
m_serializer.Serialize(command, stream);
byte[] data = stream.GetBuffer();
m_client.Send(data, (int)stream.Length, m_endpoint);
}
}
private void UdpReceivedCallback(IAsyncResult result)
{
IPEndPoint endpoint = new IPEndPoint(0, 0);
ITFtpCommand command = null;
try
{
byte[] data;
lock (this)
{
if (m_client == null)
{
return;
}
data = m_client.EndReceive(result, ref endpoint);
}
command = m_parser.Parse(data);
}
catch (SocketException e)
{
// Handle receive error
RaiseOnError(new NetworkError(e));
}
catch (TFtpParserException e2)
{
// Handle parser error
RaiseOnError(new NetworkError(e2));
}
if (command != null)
{
RaiseOnCommand(command, endpoint);
}
lock (this)
{
m_client?.BeginReceive(UdpReceivedCallback, null);
}
}
protected void SendAndRepeat(ITFtpCommand command)
{
Context.GetConnection().Send(command);
m_lastCommand = command;
ResetTimeout();
}
private void RaiseOnCommand(ITFtpCommand command, IPEndPoint endpoint)
{
OnCommandReceived?.Invoke(command, endpoint);
}
/// <summary>
/// Call this method to serialize the given <code>command</code> using the given <code>writer</code>.
/// </summary>
public void Serialize(ITFtpCommand command, Stream stream)
{
CommandComposerVisitor visitor = new CommandComposerVisitor(stream);
command.Visit(visitor);
}
public virtual void OnCommand(ITFtpCommand command, EndPoint endpoint)
{
}
