/// <summary>
/// Accept connections
/// </summary>
/// <returns></returns>
private async Task AcceptConnections()
{
listener = new TcpListener(Server.Address, Server.Port);
var bufferSize = Buffer; // Get the current buffer size on start
listener.Start();
Running = true;
// If there is an exception we want to output the message to the console for debugging
try
{
// While the Running bool is true, the listener is not null and there is no cancellation requested
while (Running && listener != null && !cancellationTokenSource.Token.IsCancellationRequested)
{
var client = await listener.AcceptTcpClientAsync().WithWaitCancellation(cancellationTokenSource.Token);
if (client != null)
{
if (ClientList.Count(definition => definition.ServerEndPoint == client.Client.LocalEndPoint) == 0)
{
var oldClients = ClientList.Where(definition => definition.ServerEndPoint == client.Client.LocalEndPoint)
.ToList();
foreach (var vncRepeaterDefinition in oldClients)
{
ClientList.Remove(vncRepeaterDefinition);
}
}
// Proxy the data from the client to the server until the end of stream filling the buffer.
if (ClientList.Count(definition => definition.ServerEndPoint == client.Client.LocalEndPoint) == 0)
{
var definition = new VNCRepeaterDefinition()
{
Authenticated = false,
FirstRequest = DateTime.UtcNow,
ClientEndPoint = (IPEndPoint)client.Client.RemoteEndPoint,
ServerEndPoint = (IPEndPoint)client.Client.LocalEndPoint
};
this.ClientList.Add(definition);
// We havent dealt with this one before.
await ProxyClientConnection(client, definition, bufferSize);
}
}
}
}
catch (Exception ex)
{
Console.WriteLine(ex.Message);
}
listener.Stop();
}
/// <summary>
/// Send and receive data between the Client and Server
/// </summary>
/// <param name="client"></param>
/// <param name="definition"></param>
/// <param name="serverStream"></param>
/// <param name="clientStream"></param>
/// <param name="bufferSize"></param>
/// <param name="cancellationToken"></param>
private void ProxyClientDataToServer(TcpClient client, VNCRepeaterDefinition definition, NetworkStream serverStream, NetworkStream clientStream, int bufferSize, CancellationToken cancellationToken)
{
byte[] message = new byte[bufferSize];
int clientBytes;
while (!cancellationToken.IsCancellationRequested)
{
try
{
clientBytes = clientStream.Read(message, 0, bufferSize);
if (BytesTransfered != null)
{
var messageTrimed = message.Reverse().SkipWhile(x => x == 0).Reverse().ToArray();
BytesTransfered(this, new ProxyByteDataEventArgs(messageTrimed, "Client"));
}
}
catch
{
// Socket error - exit loop. Client will have to reconnect.
break;
}
if (clientBytes == 0)
{
// Client disconnected.
if (definition != null)
{
this.ClientList.Remove(definition);
}
break;
}
serverStream.Write(message, 0, clientBytes);
if (ClientDataSentToServer != null)
{
ClientDataSentToServer(this, new ProxyDataEventArgs(clientBytes));
}
}
message = null;
client.Close();
}
/// <summary>
/// Send and receive data between the Server and Client
/// </summary>
/// <param name="serverStream"></param>
/// <param name="definition"></param>
/// <param name="clientStream"></param>
/// <param name="bufferSize"></param>
/// <param name="cancellationToken"></param>
private void ProxyServerDataToClient(NetworkStream serverStream, VNCRepeaterDefinition definition, NetworkStream clientStream, int bufferSize, CancellationToken cancellationToken)
{
byte[] message = new byte[bufferSize];
int serverBytes;
while (!cancellationToken.IsCancellationRequested)
{
try
{
serverBytes = serverStream.Read(message, 0, bufferSize);
if (BytesTransfered != null)
{
var messageTrimed = message.Reverse().SkipWhile(x => x == 0).Reverse().ToArray();
BytesTransfered(this, new ProxyByteDataEventArgs(messageTrimed, "Server"));
}
clientStream.Write(message, 0, serverBytes);
}
catch
{
// Server socket error - exit loop. Client will have to reconnect.
break;
}
if (serverBytes == 0)
{
// server disconnected.
if (definition != null)
{
this.ClientList.Remove(definition);
}
break;
}
if (ServerDataSentToClient != null)
{
ServerDataSentToClient(this, new ProxyDataEventArgs(serverBytes));
}
}
message = null;
}
/// <summary>
/// Process the client with a predetermined buffer size
/// </summary>
/// <param name="client"></param>
/// <param name="definition"></param>
/// <param name="bufferSize"></param>
/// <returns></returns>
private async Task ProxyClientConnection(TcpClient client, VNCRepeaterDefinition definition, int bufferSize)
{
// Get the client stream
var clientStream = client.GetStream();
// First we check if the definitions IP addresses are set to the same thing
if (Equals(definition.ClientEndPoint.Address, definition.ServerEndPoint.Address))
{
// Process as a Repeater stream
byte[] sendBytes = Encoding.ASCII.GetBytes("RFB 000.000\n");
clientStream.Write(sendBytes, 0, sendBytes.Length);
var attempts = 0;
// Send RFB back and forth until an IP Address is given
// Attempt a few times to send the RFB proto back and forth until we get something
byte[] message = new byte[bufferSize];
int clientBytes;
while (!definition.Authenticated && attempts < 10)
{
attempts += 1;
try
{
clientBytes = clientStream.Read(message, 0, bufferSize);
var messageTrimed = message.Reverse().SkipWhile(x => x == 0).Reverse().ToArray();
var messageString = Encoding.ASCII.GetString(messageTrimed);
if (messageString.Length > 5 && messageString.Contains(":"))
{
var split = messageString.Split(":".ToCharArray());
if (split.Length >= 2)
{
var ip = split[0];
var port = split[1];
var endpoint = new IPEndPoint(IPAddress.Parse(ip), Convert.ToInt32(port));
definition.ClientEndPoint = endpoint;
definition.Authenticated = true;
break;
}
sendBytes = Encoding.ASCII.GetBytes("RFB 000.000\n");
clientStream.Write(sendBytes, 0, sendBytes.Length);
}
}
catch
{
// Socket error - exit loop. Client will have to reconnect.
break;
}
if (clientBytes == 0)
{
// Client disconnected.
break;
}
}
}
else
{
definition.Authenticated = true;
}
if (definition.Authenticated)
{
// Handle this client
// Send the server data to client and client data to server - swap essentially.
TcpClient server = new TcpClient(definition.ClientEndPoint.Address.ToString(), definition.ClientEndPoint.Port);
var serverStream = server.GetStream();
var definitionToken = definition.CancellationTokenSource.Token;
var serverToken = this.cancellationTokenSource.Token;
try
{
// Continually do the proxying
new Task(() => ProxyClientDataToServer(client, definition, serverStream, clientStream, bufferSize, definitionToken), serverToken).Start();
new Task(() => ProxyServerDataToClient(serverStream, definition, clientStream, bufferSize, definitionToken), serverToken).Start();
}
catch (Exception ex)
{
Console.WriteLine(ex.Message);
}
}
}
/// <summary>
/// Accept connections
/// </summary>
/// <returns></returns>
private async Task AcceptConnections()
{
listener = new TcpListener(Server.Address, Server.Port);
var bufferSize = Buffer; // Get the current buffer size on start
listener.Start();
Running = true;
// If there is an exception we want to output the message to the console for debugging
try
{
// While the Running bool is true, the listener is not null and there is no cancellation requested
while (Running && listener != null && !cancellationTokenSource.Token.IsCancellationRequested)
{
var client = await listener.AcceptTcpClientAsync().WithWaitCancellation(cancellationTokenSource.Token);
if (client != null)
{
if (ClientList.Count(definition => definition.ServerEndPoint == client.Client.LocalEndPoint) == 0)
{
var oldClients = ClientList.Where(definition => definition.ServerEndPoint == client.Client.LocalEndPoint)
.ToList();
foreach (var vncRepeaterDefinition in oldClients)
{
ClientList.Remove(vncRepeaterDefinition);
}
}
// Proxy the data from the client to the server until the end of stream filling the buffer.
if (ClientList.Count(definition => definition.ServerEndPoint == client.Client.LocalEndPoint) == 0)
{
var definition = new VNCRepeaterDefinition()
{
Authenticated = false,
FirstRequest = DateTime.UtcNow,
ClientEndPoint = (IPEndPoint)client.Client.RemoteEndPoint,
ServerEndPoint = (IPEndPoint)client.Client.LocalEndPoint
};
this.ClientList.Add(definition);
// We havent dealt with this one before.
await ProxyClientConnection(client, definition, bufferSize);
}
}
}
}
catch (Exception ex)
{
Console.WriteLine(ex.Message);
}
listener.Stop();
}
/// <summary>
/// Process the client with a predetermined buffer size
/// </summary>
/// <param name="client"></param>
/// <param name="definition"></param>
/// <param name="bufferSize"></param>
/// <returns></returns>
private async Task ProxyClientConnection(TcpClient client, VNCRepeaterDefinition definition, int bufferSize)
{
// Get the client stream
var clientStream = client.GetStream();
// First we check if the definitions IP addresses are set to the same thing
if (Equals(definition.ClientEndPoint.Address, definition.ServerEndPoint.Address))
{
// Process as a Repeater stream
byte[] sendBytes = Encoding.ASCII.GetBytes("RFB 000.000\n");
clientStream.Write(sendBytes, 0, sendBytes.Length);
var attempts = 0;
// Send RFB back and forth until an IP Address is given
// Attempt a few times to send the RFB proto back and forth until we get something
byte[] message = new byte[bufferSize];
int clientBytes;
while (!definition.Authenticated && attempts < 10)
{
attempts += 1;
try
{
clientBytes = clientStream.Read(message, 0, bufferSize);
var messageTrimed = message.Reverse().SkipWhile(x => x == 0).Reverse().ToArray();
var messageString = Encoding.ASCII.GetString(messageTrimed);
if (messageString.Length > 5 && messageString.Contains(":"))
{
var split = messageString.Split(":".ToCharArray());
if (split.Length >= 2)
{
var ip = split[0];
var port = split[1];
var endpoint = new IPEndPoint(IPAddress.Parse(ip), Convert.ToInt32(port));
definition.ClientEndPoint = endpoint;
definition.Authenticated = true;
break;
}
sendBytes = Encoding.ASCII.GetBytes("RFB 000.000\n");
clientStream.Write(sendBytes, 0, sendBytes.Length);
}
}
catch
{
// Socket error - exit loop. Client will have to reconnect.
break;
}
if (clientBytes == 0)
{
// Client disconnected.
break;
}
}
}
else
{
definition.Authenticated = true;
}
if (definition.Authenticated)
{
// Handle this client
// Send the server data to client and client data to server - swap essentially.
TcpClient server = new TcpClient(definition.ClientEndPoint.Address.ToString(), definition.ClientEndPoint.Port);
var serverStream = server.GetStream();
var definitionToken = definition.CancellationTokenSource.Token;
var serverToken = this.cancellationTokenSource.Token;
try
{
// Continually do the proxying
new Task(() => ProxyClientDataToServer(client, definition, serverStream, clientStream, bufferSize, definitionToken), serverToken).Start();
new Task(() => ProxyServerDataToClient(serverStream, definition, clientStream, bufferSize, definitionToken), serverToken).Start();
}
catch (Exception ex)
{
Console.WriteLine(ex.Message);
}
}
}
/// <summary>
/// Send and receive data between the Server and Client
/// </summary>
/// <param name="serverStream"></param>
/// <param name="definition"></param>
/// <param name="clientStream"></param>
/// <param name="bufferSize"></param>
/// <param name="cancellationToken"></param>
private void ProxyServerDataToClient(NetworkStream serverStream, VNCRepeaterDefinition definition, NetworkStream clientStream, int bufferSize, CancellationToken cancellationToken)
{
byte[] message = new byte[bufferSize];
int serverBytes;
while (!cancellationToken.IsCancellationRequested)
{
try
{
serverBytes = serverStream.Read(message, 0, bufferSize);
if (BytesTransfered != null)
{
var messageTrimed = message.Reverse().SkipWhile(x => x == 0).Reverse().ToArray();
BytesTransfered(this, new ProxyByteDataEventArgs(messageTrimed, "Server"));
}
clientStream.Write(message, 0, serverBytes);
}
catch
{
// Server socket error - exit loop. Client will have to reconnect.
break;
}
if (serverBytes == 0)
{
// server disconnected.
if (definition != null)
{
this.ClientList.Remove(definition);
}
break;
}
if (ServerDataSentToClient != null)
{
ServerDataSentToClient(this, new ProxyDataEventArgs(serverBytes));
}
}
message = null;
}
/// <summary>
/// Send and receive data between the Client and Server
/// </summary>
/// <param name="client"></param>
/// <param name="definition"></param>
/// <param name="serverStream"></param>
/// <param name="clientStream"></param>
/// <param name="bufferSize"></param>
/// <param name="cancellationToken"></param>
private void ProxyClientDataToServer(TcpClient client, VNCRepeaterDefinition definition, NetworkStream serverStream, NetworkStream clientStream, int bufferSize, CancellationToken cancellationToken)
{
byte[] message = new byte[bufferSize];
int clientBytes;
while (!cancellationToken.IsCancellationRequested)
{
try
{
clientBytes = clientStream.Read(message, 0, bufferSize);
if (BytesTransfered != null)
{
var messageTrimed = message.Reverse().SkipWhile(x => x == 0).Reverse().ToArray();
BytesTransfered(this, new ProxyByteDataEventArgs(messageTrimed, "Client"));
}
}
catch
{
// Socket error - exit loop. Client will have to reconnect.
break;
}
if (clientBytes == 0)
{
// Client disconnected.
if (definition != null)
{
this.ClientList.Remove(definition);
}
break;
}
serverStream.Write(message, 0, clientBytes);
if (ClientDataSentToServer != null)
{
ClientDataSentToServer(this, new ProxyDataEventArgs(clientBytes));
}
}
message = null;
client.Close();
}
