private static void StartRemoteConnection(ConnectToRemoteState state)
{
if (state.RequestMethod.Equals("CONNECT", StringComparison.InvariantCultureIgnoreCase))
{
// handle SSL response for CONNECT
HandleSslConnect(state);
return;
}
var remoteip = GetRemoteIp(state.RemoteHost); // TODO: handle SocketError.HostNotFound
if (remoteip == null)
{
WriteLog(state.Session, 0, "ERR");
return;
}
var remoteClient = new TcpClient();
var remoteConnectionState = new RemoteConnectionState
{
Session = state.Session,
ClientStream = state.ClientStream,
Client = state.Client,
MessageStream = state.MessageStream,
RemoteClient = remoteClient,
RemoteHost = state.RemoteHost,
IsSsl = state.IsSsl
};
remoteClient.BeginConnect(remoteip, state.RemotePort, ConnectToRemote.Run, remoteConnectionState);
}
private static void HandleSslConnect(ConnectToRemoteState state)
{
var connectStreamWriter = new StreamWriter(state.ClientStream);
connectStreamWriter.WriteLine("HTTP/1.0 200 Connection established");
connectStreamWriter.WriteLine("Timestamp: {0}", DateTime.Now);
connectStreamWriter.WriteLine("Proxy-agent: GOS Proxy Service");
connectStreamWriter.WriteLine();
connectStreamWriter.Flush();
var sslStream = new SslStream(state.ClientStream, false);
try
{
var certProvider = new CertificateProvider();
bool created;
var certificate = certProvider.LoadOrCreateCertificate(state.RemoteHost, out created);
sslStream.AuthenticateAsServer(certificate, false, SslProtocols.Tls | SslProtocols.Ssl3 | SslProtocols.Ssl2, true);
}
catch (Exception ex)
{
WriteLog(state.Session, 0, "ERR", ex.Message);
sslStream.Close();
state.ClientStream.Close();
connectStreamWriter.Close();
return;
}
var nstate = new ClientConnectionState
{
Session = state.Session,
Client = state.Client,
ClientStream = sslStream,
ClientStreamBase = (NetworkStream)state.ClientStream,
Buffer = new byte[Globals.BufferSize],
MessageStream = new MemoryStream(),
IsSsl = true,
};
try
{
sslStream.BeginRead(nstate.Buffer, 0, nstate.Buffer.Length, ReadFromClient.Run, nstate);
}
catch (Exception ex)
{
WriteLog(state.Session, 0, "ERR", ex.Message);
sslStream.Close();
state.ClientStream.Close();
}
}
public static void Run(IAsyncResult asyncResult)
{
var state = asyncResult.AsyncState as ClientConnectionState;
if (state != null)
{
int read;
try
{
read = state.ClientStream.EndRead(asyncResult);
}
catch (Exception ex)
{
WriteLog(state.Session, 0, "ERR", ex.Message);
state.ClientStreamBase.Close();
state.ClientStream.Close();
return;
}
state.MessageStream.Write(state.Buffer, 0, read);
if (state.ClientStreamBase.DataAvailable)
{
state.ClientStream.BeginRead(state.Buffer, 0, state.Buffer.Length, ReadFromClient.Run, state);
}
else
{
if (read == 0)
{
state.ClientStream.Close();
return;
}
var messageHeader = ParseClientMessage(state.MessageStream);
if (messageHeader == null)
{
state.ClientStream.Close();
state.ClientStreamBase.Close();
return;
}
state.ClientMessageHeader = messageHeader;
state.Session.TargetUrl = state.ClientMessageHeader.RemoteUri.ToString();
state.Session.Protocoll = state.ClientMessageHeader.Protocol;
// TODO: filter the data from the client
var connectState = new ConnectToRemoteState
{
Session = state.Session,
RemotePort = state.ClientMessageHeader.RemoteUri.Port,
RemoteHost = state.ClientMessageHeader.RemoteUri.Host,
RequestMethod = state.ClientMessageHeader.Method,
Client = state.Client,
ClientStream = state.ClientStream,
MessageStream = state.MessageStream,
IsSsl = state.IsSsl
};
StartRemoteConnection(connectState);
}
}
}
