I created an application with server and client tool using sockets etc. When using my code on my computer works. Now I installed the Himachi software and I need to use this software in my application so that when a user connects with me, the application created could be used in this network. Note that this is my first time using sockets. The problem is that they are not connecting to each other and also it gives me this error on changing the ip and port: The requested address is not valid in its context
The send Tool
public Send(string Group, string port, string ttl, string rep, string data)
{
IPAddress ip;
try
{
Console.WriteLine("Send on Group: {0} Port: {1} TTL: {2}", Group,port,ttl);
ip = IPAddress.Parse(Group);
Socket s = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);
s.SetSocketOption(SocketOptionLevel.IP, SocketOptionName.AddMembership, new MulticastOption(ip));
s.SetSocketOption(SocketOptionLevel.IP, SocketOptionName.MulticastTimeToLive, int.Parse(ttl));
IPEndPoint ipep = new IPEndPoint(IPAddress.Parse(Group),int.Parse(port));
Console.WriteLine("Connecting...");
s.Connect(ipep);
byte[] byData = System.Text.Encoding.ASCII.GetBytes(data);
s.Send(byData, SocketFlags.None);
Console.WriteLine("Closing Connection...");
s.Close();
}
catch(System.Exception e) { Console.Error.WriteLine(e.Message); }
}
The Receive tool
public string RecvData(string Group, string port)
{
string str = "";
Socket s = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);
IPEndPoint ipep = new IPEndPoint(IPAddress.Any, int.Parse(port));
s.Bind(ipep);
IPAddress ip = IPAddress.Parse(Group);
s.SetSocketOption(SocketOptionLevel.IP, SocketOptionName.AddMembership, new MulticastOption(ip,IPAddress.Any));
// Getting the data
byte[] buffer = new byte[1024];
int iRx = s.Receive(buffer);
str = System.Text.Encoding.ASCII.GetString(buffer, 0, buffer.Length);
// Closing a Socket
s.Close();
return str;
}
Thanks
So your problem is that you are trying to use a VPN (hamachi) to connect two apps the server and the client so that the client can receive messages from the server right? I think that the error given "The requested address is not valid in its context" is because you are using a VPN but I don't know how this can be solved sorry. What I think is that maybe you might also need the network id and password but again I'm not sure. Please keep us informed because this is a very interesting question.
Related
I am having trouble with my c# tcp code.
When I run the server and the client on the same computer, it will connect just fine.
But when I run the client on a different PC or on a phone, I get: A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond.
Here is the server code:
private static void CreateServer()
{
TcpListener server = null;
try
{
Int32 port = 13000;
IPAddress localAddr = IPAddress.Parse("127.0.0.1");
server = new TcpListener(localAddr, port);
server.Start();
Byte[] bytes = new Byte[256];
String data = null;
while (true)
{
Console.Write("Waiting for a connection... ");
/*
IPHostEntry ipHostInfo = Dns.GetHostEntry(Dns.GetHostName());
var ipAddress = ipHostInfo.AddressList;
Console.WriteLine(ipHostInfo.HostName);
Console.WriteLine(ipAddress[0]);
*/
TcpClient client = server.AcceptTcpClient();
Console.WriteLine("Connected!");
data = null;
NetworkStream stream = client.GetStream();
int i;
try
{
while ((i = stream.Read(bytes, 0, bytes.Length)) != 0)
{
data = System.Text.Encoding.ASCII.GetString(bytes, 0, i);
Console.WriteLine("Received: {0}", data);
data = data.ToUpper();
byte[] msg = System.Text.Encoding.ASCII.GetBytes(data);
stream.Write(msg, 0, msg.Length);
}
}
catch(IOException e)
{
//Console.WriteLine(e);
Console.WriteLine("Restarting Server");
//client.Close();
//CreateServer();
}
// Shutdown and end connection
client.Close();
}
}
catch (SocketException e)
{
//Console.WriteLine("SocketException: {0}", e);
}
finally
{
// Stop listening for new clients.
server.Stop();
}
Console.WriteLine("\nHit enter to continue...");
Console.Read();
}
I removed most of the comments. But that is the basic example for a tcp server from the documentation.
the client connect code is very simple:
tcpClient = new TcpClient();
tcpClient.Connect("192.168.0.7", 13000);
with the declaration for tcpClient saved in a less local spot for retaining and quickly reconnecting.
What I have tried:
I have made sure the IP address is correct, I even port forwarded and used my external IP, but got the same issue.
I made sure the firewall is not blocking the app on either device.
I tried using either device as the server.
I've looked up the problem and the only other person to have this issue needed to make sure he put in the correct IP and fix his firewall settings. I'm probably missing something super obvious.
One final piece of information, one device is wired to the router, I don't know if that is messing with anything.
One other thing, I tried:
tcpClient.Connect(new IPEndPoint(IPAddress.Parse("192.168.0.7"), 13000));
as well.
Whelp I was right. It was something very obvious and honestly dumb on my part.
on the server side:
IPAddress localAddr = IPAddress.Parse("127.0.0.1");
does not result in the server listening on its ipv4, instead it listens on an ipv6
so what you want:
Remove the localAddr declaration, as it is not important, and instead of calling:
server = new TcpListener(localAddr, port);
call:
server = new TcpListener(IPAddress.Any, port);
IPAddress.Any is used to listen across all of the network interfaces the device has.
I'm trying to implement Hole punching using C# but unfortunately I spent hours to figure out why it doesn't work for me. Here is my problem:
I have a third part server that I can manage all external IPs for the peers on, and of course my router is behind a NAT, and I assume all my peers are also behind NATs.
Say if I managed to figure out all slaves (peers), End points (external ips). Where to put the external ip address of my server which runs on my pc (not the third party one), and where to put the peer ip address?
This is my code:
public void HolePunch(String ServerIp, Int32 Port) // if I put my external ip here I get Exception (An address incompatible with the requested protocol was used)
{
IPEndPoint LocalPt = new IPEndPoint(Dns.GetHostEntry(Dns.GetHostName()).AddressList[0], Port);
UdpClient Client = new UdpClient();
Client.ExclusiveAddressUse = false;
Client.Client.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.ReuseAddress, true);
Client.Client.Bind(LocalPt);
IPEndPoint RemotePt = new IPEndPoint(IPAddress.Parse(ServerIp), Port);
// This Part Sends your local endpoint to the server so if the two peers are on the same nat they can bypass it, you can omit this if you wish to just use the remote endpoint.
byte[] IPBuffer = System.Text.Encoding.UTF8.GetBytes(Dns.GetHostEntry(Dns.GetHostName()).AddressList[0].ToString());
byte[] LengthBuffer = BitConverter.GetBytes(IPBuffer.Length);
byte[] PortBuffer = BitConverter.GetBytes(Port);
byte[] Buffer = new byte[IPBuffer.Length + LengthBuffer.Length + PortBuffer.Length];
LengthBuffer.CopyTo(Buffer,0);
IPBuffer.CopyTo(Buffer, LengthBuffer.Length);
PortBuffer.CopyTo(Buffer, IPBuffer.Length + LengthBuffer.Length);
Client.BeginSend(Buffer, Buffer.Length, RemotePt, new AsyncCallback(SendCallback), Client);
// Wait to receve something
BeginReceive(Client, Port);
// you may want to use a auto or manual ResetEvent here and have the server send back a confirmation, the server should have now stored your local (you sent it) and remote endpoint.
// you now need to work out who you need to connect to then ask the server for there remote and local end point then need to try to connect to the local first then the remote.
// if the server knows who you need to connect to you could just have it send you the endpoints as the confirmation.
// you may also need to keep this open with a keepalive packet untill it is time to connect to the peer or peers.
// once you have the endpoints of the peer you can close this connection unless you need to keep asking the server for other endpoints
Client.Close();
}
public void ConnectToPeer(String PeerIp, Int32 Port)
{
IPEndPoint LocalPt = new IPEndPoint(Dns.GetHostEntry(Dns.GetHostName()).AddressList[0], Port);
UdpClient Client = new UdpClient();
Client.ExclusiveAddressUse = false;
Client.Client.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.ReuseAddress, true);
Client.Client.Bind(LocalPt);
IPEndPoint RemotePt = new IPEndPoint(IPAddress.Parse(PeerIp), Port);
Client.Connect(RemotePt);
//you may want to keep the peer client connections in a list.
BeginReceive(Client, Port);
}
public void SendCallback(IAsyncResult ar)
{
UdpClient Client = (UdpClient)ar.AsyncState;
Client.EndSend(ar);
}
public void BeginReceive(UdpClient Client, Int32 Port)
{
IPEndPoint ListenPt = new IPEndPoint(IPAddress.Any, Port);
Object[] State = new Object[] { Client, ListenPt };
Client.BeginReceive(new AsyncCallback(ReceiveCallback), State);
}
public void ReceiveCallback(IAsyncResult ar)
{
UdpClient Client = (UdpClient)((Object[])ar.AsyncState)[0];
IPEndPoint ListenPt = (IPEndPoint)((Object[])ar.AsyncState)[0];
Byte[] receiveBytes = Client.EndReceive(ar, ref ListenPt);
}
EDIT :
the code works will if I give it my local ip and if my clients in my pc .. but if I supply it an external ip it doesn't work ( the exception in the first line comment )
I've made a simple chat application in c#.net that sends and receives data between 2 computers.
So, I used this method to send the data:
int port = 11000;
private void send(string data, string ip)
{
Socket sending_socket = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);
IPEndPoint sending_end_point = null;
byte[] send_buffer = Encoding.ASCII.GetBytes(data);
sending_end_point = new IPEndPoint(IPAddress.Parse(ip), port);
try { sending_socket.SendTo(send_buffer, sending_end_point); }
catch { }
}
And to receive I used this:
string receiveddata = "";
private void backgroundWorker1_DoWork(object sender, DoWorkEventArgs e)
{
UdpClient listener = new UdpClient(port);
IPEndPoint groupEP = new IPEndPoint(IPAddress.Any, port);
byte[] receive_byte_array;
try
{
receive_byte_array = listener.Receive(ref groupEP);
receiveddata = Encoding.ASCII.GetString(receive_byte_array, 0, receive_byte_array.Length);
}
catch { }
listener.Close();
}
This works without any problems between 2 computers on a LAN, but I would like to know (if possible) how to do the same thing over the Internet.
From what I've searched on the Internet, it seems that I have to use port-forwarding in order to do that, so I already did that, but I don't know what should I do know.
So my question is, how should I change this code (if I have to) so I could send and receive data (UDP) over the internet, assuming I have port-forwarded correctly already and assuming I know the external IPs of both routers?
Thank you in advance.
This should work just fine, as long as your (public) IP-address is correct and the ports are forwarded correctly on your router (meaning, forwarded to the correct private IP, on the correct protocol, in your case UDP).
You are aware that this is UDP though, so it's not reliable data transfer.
I have some client-server socket code that I want to be able to construct and (re)connect to periodically the same endpoint address: localhost:17999
Here is the server:
// Listen for a connection:
IPEndPoint localEndPoint = new IPEndPoint(IPAddress.Loopback, 17999);
Socket listener = new Socket(IPAddress.Loopback.AddressFamily, SocketType.Stream, ProtocolType.Tcp);
listener.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.ReuseAddress, true);
listener.Bind(localEndPoint);
listener.Listen(1);
// Accept the connection and send a message:
Socket handler = listener.Accept();
byte[] bytes = new byte[1024];
bytes = Encoding.ASCII.GetBytes("The Message...");
handler.Send(bytes);
// Clean up
handler.Shutdown(SocketShutdown.Both);
handler.Close();
handler.Dispose();
listener.Shutdown(SocketShutdown.Both);
listener.Close();
listener.Dispose();
And here is the client:
byte[] bytes = new byte[1024];
Socket receiver = new Socket(IPAddress.Loopback.AddressFamily, SocketType.Stream, ProtocolType.Tcp);
receiver.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.ReuseAddress, true);
receiver.Connect(new IPEndPoint(IPAddress.Loopback, 17999));
int num_bytes_received = receiver.Receive(bytes);
string result = Encoding.ASCII.GetString(bytes, 0, num_bytes_received);
receiver.Shutdown(SocketShutdown.Both);
receiver.Close();
receiver.Dispose();
When I create the client and server for the first time, it works fine. However when I create it again, I get an error:
"A request to send or receive data was disallowed because the socket is
not conne cted and (when sending on a datagram socket using a sendto
call) no address was supplied"
I would like to be able to spin up this mechanism arbitrarily whenever I need to with the following order of events:
Launch the server and wait to accept a connection
Launch the client and connect to the server
Accept the client connection at the server
Send a message to the client
Repeat when necessary
How can I do this?
Thx in Advance!
EDIT: Each time I build the client and server objects it is from a different process.
You have two issues:
1) You're closing the listener. Just leave it open.
2) You're setting ReuseAddress on the wrong socket and way too late. Set it on the listening socket before you call bind (since that's when you use the address).
Setting ReuseAddress on a socket you aren't going to bind doesn't do anything. You can remove that from the client.
I tried what Gene suggested and it seems to work:
// Listen for a connection:
IPEndPoint localEndPoint = new IPEndPoint(IPAddress.Loopback, 17999);
using (Socket listener = new Socket(IPAddress.Loopback.AddressFamily, SocketType.Stream, ProtocolType.Tcp))
{
listener.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.ReuseAddress, true);
listener.Bind(localEndPoint);
listener.Listen(1);
Thread t = new Thread(() =>
{
// Accept the connection and send a message:
using (Socket handler = listener.Accept())
{
byte[] bytes = new byte[1024];
bytes = Encoding.ASCII.GetBytes("The Message...");
handler.Send(bytes);
}
});
t.Start();
t.Join();
}
Thanks, all!
I am trying to fetch the IP address from the broadcast packets sent by a DSL modem and received on port 137 using UDP protocol. I am able to read the IP address when connectivity is present.
However, in unidentified network state, when my modem is configured for DHCP, and a specific range of IPs are allowed, and setting on my machine is auto-detect:
I get the default Local IP Address of the machine on reading the broadcast messages. That would be starting with 169.
Note: I am restarting the modem in order to receive the broadcast messages.
Socket sock = new Socket(AddressFamily.InterNetwork,
SocketType.Dgram, ProtocolType.Udp);
IPEndPoint iep = new IPEndPoint(IPAddress.Any, 137);
sock.Bind(iep);
EndPoint ep = (EndPoint)iep;
int iLoopCount=0;
while (iLoopCount <= 10000)
{
Console.WriteLine("Ready to receive…");
byte[] data = new byte[1024];
int recv = sock.ReceiveFrom(data, ref ep);
string stringData = Encoding.Default.GetString(data, 0, recv);
Console.WriteLine("{1}: from: {0}",((IPEndPoint)ep).Address.ToString(),DateTime.Now.ToString());
iLoopCount++;
// Console.WriteLine(sock.RemoteEndPoint.ToString());
}
sock.Close();
Console.Read();
Found the answer to my question at
http://www.codeproject.com/Articles/17031/A-Network-Sniffer-in-C