|
public BeginConnect ( |
||
| remoteEP | An |
|
| callback | AsyncCallback | The |
| state | object | An object that contains state information for this request. |
| return | IAsyncResult | |
public void Start()
{
// create a new ManualResetEvent. This will be used to make the main application
// thread wait until the full server reply has been received.
m_ResetEvent = new ManualResetEvent(false);
// initialize the security options
SecurityOptions options = new SecurityOptions(
SecureProtocol.Ssl3 | SecureProtocol.Tls1, // use SSL3 or TLS1
null, // do not use client authentication
ConnectionEnd.Client, // this is the client side
CredentialVerification.None, // do not check the certificate -- this should not be used in a real-life application :-)
null, // not used with automatic certificate verification
"www.microsoft.com", // this is the common name of the Microsoft web server
SecurityFlags.Default, // use the default security flags
SslAlgorithms.SECURE_CIPHERS, // only use secure ciphers
null); // do not process certificate requests.
try {
// create the securesocket with the specified security options
m_Socket = new SecureSocket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp, options);
// resolve www.microsoft.com
IPEndPoint endpoint = new IPEndPoint(Dns.GetHostEntry("www.microsoft.com").AddressList[0], 443);
// start connecting to www.microsoft.com
m_Socket.BeginConnect(endpoint, new AsyncCallback(this.OnConnect), null);
// wait until the entire web page has been received
m_ResetEvent.WaitOne();
// close the SecureSocket
m_Socket.Close();
} catch {
OnError("Could not connect to the website");
}
}
///<summary>Initializes a new instance of the FtpDataConnection class.</summary>
///<param name="RemoteAddress">The address on the local FTP client to connect to.</param>
///<returns>The PORT command string to send to the FTP server.</returns>
public string ProcessPort(IPEndPoint RemoteAddress) {
try {
ListenSocket = new SecureSocket(IPAddress.Any.AddressFamily, SocketType.Stream, ProtocolType.Tcp);
ListenSocket.Bind(new IPEndPoint(IPAddress.Any, 0));
ListenSocket.Listen(1);
ListenSocket.BeginAccept(new AsyncCallback(this.OnPortAccept), ListenSocket);
ClientSocket = new SecureSocket(RemoteAddress.AddressFamily, SocketType.Stream, ProtocolType.Tcp);
ClientSocket.BeginConnect(RemoteAddress, new AsyncCallback(this.OnPortConnected), ClientSocket);
return "PORT " + Listener.GetLocalExternalIP().ToString().Replace('.', ',') + "," + Math.Floor(((IPEndPoint)ListenSocket.LocalEndPoint).Port / 256).ToString() + "," + (((IPEndPoint)ListenSocket.LocalEndPoint).Port % 256).ToString() + "\r\n";
} catch {
Dispose();
return "PORT 0,0,0,0,0,0\r\n";
}
}
///<summary>Processes a SOCKS request from a client.</summary>
///<param name="Request">The request to process.</param>
protected override void ProcessRequest(byte [] Request) {
int Ret;
try {
if (Request[0] == 1) { // CONNECT
IPAddress RemoteIP;
int RemotePort = Request[1] * 256 + Request[2];
Ret = Array.IndexOf(Request, (byte)0, 7);
Username = Encoding.ASCII.GetString(Request, 7, Ret - 7);
if (Request[3] == 0 && Request[4] == 0 && Request[5] == 0 && Request[6] != 0) {// Use remote DNS
Ret = Array.IndexOf(Request, (byte)0, Ret + 1);
RemoteIP = Dns.Resolve(Encoding.ASCII.GetString(Request, Username.Length + 8, Ret - Username.Length - 8)).AddressList[0];
} else { //Do not use remote DNS
RemoteIP = IPAddress.Parse(Request[3].ToString() + "." + Request[4].ToString() + "." + Request[5].ToString() + "." + Request[6].ToString());
}
RemoteConnection = new SecureSocket(RemoteIP.AddressFamily, SocketType.Stream, ProtocolType.Tcp);
RemoteConnection.BeginConnect(new IPEndPoint(RemoteIP, RemotePort), new AsyncCallback(this.OnConnected), RemoteConnection);
} else if (Request[0] == 2) { // BIND
byte [] Reply = new byte[8];
long LocalIP = Listener.GetLocalExternalIP().Address;
AcceptSocket = new SecureSocket(IPAddress.Any.AddressFamily, SocketType.Stream, ProtocolType.Tcp);
AcceptSocket.Bind(new IPEndPoint(IPAddress.Any, 0));
AcceptSocket.Listen(50);
RemoteBindIP = IPAddress.Parse(Request[3].ToString() + "." + Request[4].ToString() + "." + Request[5].ToString() + "." + Request[6].ToString());
Reply[0] = 0; //Reply version 0
Reply[1] = 90; //Everything is ok :)
Reply[2] = (byte)(Math.Floor(((IPEndPoint)AcceptSocket.LocalEndPoint).Port / 256)); //Port/1
Reply[3] = (byte)(((IPEndPoint)AcceptSocket.LocalEndPoint).Port % 256); //Port/2
Reply[4] = (byte)(Math.Floor((LocalIP % 256))); //IP Address/1
Reply[5] = (byte)(Math.Floor((LocalIP % 65536) / 256)); //IP Address/2
Reply[6] = (byte)(Math.Floor((LocalIP % 16777216) / 65536)); //IP Address/3
Reply[7] = (byte)(Math.Floor(LocalIP / 16777216)); //IP Address/4
Connection.BeginSend(Reply, 0, Reply.Length, SocketFlags.None, new AsyncCallback(this.OnStartAccept), Connection);
}
} catch {
Dispose(91);
}
}
///<summary>Connects to the specified endpoint.</summary>
///<param name="RemoteServer">The IPEndPoint to connect to.</param>
///<exception cref="SocketException">There was an error connecting to the specified endpoint</exception>
private void ConnectTo(IPEndPoint RemoteServer) {
if (DestinationSocket != null) {
try {
DestinationSocket.Shutdown(SocketShutdown.Both);
} catch {
} finally {
DestinationSocket.Close();
}
}
try {
DestinationSocket = new SecureSocket(RemoteServer.AddressFamily, SocketType.Stream, ProtocolType.Tcp);
DestinationSocket.BeginConnect(RemoteServer, new AsyncCallback(this.OnRemoteConnected), DestinationSocket);
} catch {
throw new SocketException();
}
}
///<summary>Processes a received query.</summary>
///<param name="Query">The query to process.</param>
private void ProcessQuery(byte [] Query) {
try {
switch(Query[1]) {
case 1: //CONNECT
IPAddress RemoteIP = null;
int RemotePort = 0;
if (Query[3] == 1) {
RemoteIP = IPAddress.Parse(Query[4].ToString() + "." + Query[5].ToString() + "." + Query[6].ToString() + "." + Query[7].ToString());
RemotePort = Query[8] * 256 + Query[9];
} else if( Query[3] == 3) {
RemoteIP = Dns.Resolve(Encoding.ASCII.GetString(Query, 5, Query[4])).AddressList[0];
RemotePort = Query[4] + 5;
RemotePort = Query[RemotePort] * 256 + Query[RemotePort + 1];
}
RemoteConnection = new SecureSocket(RemoteIP.AddressFamily, SocketType.Stream, ProtocolType.Tcp);
RemoteConnection.BeginConnect(new IPEndPoint(RemoteIP, RemotePort), new AsyncCallback(this.OnConnected), RemoteConnection);
break;
case 2: //BIND
byte [] Reply = new byte[10];
long LocalIP = Listener.GetLocalExternalIP().Address;
AcceptSocket = new SecureSocket(IPAddress.Any.AddressFamily, SocketType.Stream, ProtocolType.Tcp);
AcceptSocket.Bind(new IPEndPoint(IPAddress.Any, 0));
AcceptSocket.Listen(50);
Reply[0] = 5; //Version 5
Reply[1] = 0; //Everything is ok :)
Reply[2] = 0; //Reserved
Reply[3] = 1; //We're going to send a IPv4 address
Reply[4] = (byte)(Math.Floor((LocalIP % 256))); //IP Address/1
Reply[5] = (byte)(Math.Floor((LocalIP % 65536) / 256)); //IP Address/2
Reply[6] = (byte)(Math.Floor((LocalIP % 16777216) / 65536)); //IP Address/3
Reply[7] = (byte)(Math.Floor(LocalIP / 16777216)); //IP Address/4
Reply[8] = (byte)(Math.Floor(((IPEndPoint)AcceptSocket.LocalEndPoint).Port / 256)); //Port/1
Reply[9] = (byte)(((IPEndPoint)AcceptSocket.LocalEndPoint).Port % 256); //Port/2
Connection.BeginSend(Reply, 0, Reply.Length, SocketFlags.None, new AsyncCallback(this.OnStartAccept), Connection);
break;
case 3: //ASSOCIATE
//ASSOCIATE is not implemented (yet?)
Dispose(7);
break;
default:
Dispose(7);
break;
}
} catch {
Dispose(1);
}
}
///<summary>Processes a PASV reply from the server.</summary>
///<param name="Reply">The reply to process.</param>
private void ProcessPasvReply(string Reply) {
try {
IPEndPoint ConnectTo = ParsePasvIP(Reply);
DestinationSocket = new SecureSocket(ConnectTo.AddressFamily, SocketType.Stream, ProtocolType.Tcp);
DestinationSocket.BeginConnect(ConnectTo, new AsyncCallback(this.OnPasvConnected), DestinationSocket);
} catch {
Dispose();
}
}
