Simple Socks Server

Creates a simple SOCKS5 server and exposes additional SOCKS5 proxy events.

Installation

npm install simple-socks

Example Usage

In the examples folder exists two examples, one that requires no authentication and one that requires username/password authentication. Below is a basic no authentication example:

'use strict';

var
	socks5 = require('simple-socks'),
	server = socks5.createServer().listen(1080);

// When a reqest arrives for a remote destination
server.on('proxyConnect', function (info, destination) {
	console.log('connected to remote server at %s:%d', info.host, info.port);

	destination.on('data', function (data) {
		console.log(data.length);
	});
});

// When data arrives from the remote connection
server.on('proxyData', function (data) {
	console.log(data.length);
});

// When an error occurs connecting to remote destination
server.on('proxyError', function (err) {
	console.error('unable to connect to remote server');
	console.error(err);
});

// When a proxy connection ends
server.on('proxyEnd', function (response, args) {
	console.log('socket closed with code %d', response);
	console.log(args);
});

Running The Examples

No Authentication

For a SOCKS5 server that does not require authentication, look at examples/createServer.js:

node examples/createServer

In a separate terminal window:

curl http://www.google.com --socks5 127.0.0.1:1080

Username/Password Authentication

For a SOCKS5 server that requires username/password authentication, look at examples/createServerWithAuthentication.js:

node examples/createServerWithAuthentication

In a separate terminal window:

curl http://www.google.com --socks5 127.0.0.1:1080 --proxy-user foo:bar

Methods

createServer

Creates an instances of a SOCKS5 proxy server:

var server = require('simple-socks').createServer();

server.listen(1080, '0.0.0.0', function () {
	console.log('SOCKS5 proxy server started on 0.0.0.0:1080');
});

This method accepts an optional options argument:

• options.authentication - A callback for authentication

authentication

To make the socks5 server require username/password authentication, supply a function callback in the options as follows:

var socks5 = require('simple-socks');

var options = {
	authenticate : function (username, password, callback) {
		if (username === 'foo' && password === 'bar') {
			return setImmediate(callback);
		}

		return setImmediate(callback, new Error('incorrect username and password'));
	}
};

var server = socks5.createServer(options);

// begin listening and require user/pass authentication
server.listen(1080);

The authenticate callback accepts three arguments:

• username - username of the proxy user
• password - password of the proxy user
• callback - callback for authentication... if authentication is successful, the callback should be called with no arguments

Events

The socks5 server supports all events that exist on a native net.Server object. Additionally, the following events have been added that are specific to the SOCKS5 proxy:

• handshake - The first event fired and it occurs when a new SOCKS5 client proxy negotiation occurs
• authenticate - When username/password authentication is configured (see above), this event is fired when a successful authentication occurs
• authenticateError - When username/password authentication is configured, this event is fired when authentication fails
• proxyConnect - After handshake and optional authentication, this event is emitted upon successful connection with the remote destination
• proxyError - If connection to the remote destination fails, this event is emitted
• proxyData - When data is recieved from the remote destination, this event is fired
• proxyEnd - This event is emitted when the SOCKS5 client connection is closed for any reason

handshake

This is event is emitted when a socks5 client connects to the server. The callback accepts a single argument:

• socket - this is the originating TCP net.Socket

// When a new request is initiated
server.on('handshake', function (socket) {
	console.log('new socks5 client from %s:%d', socket.remoteAddress, socket.remotePort);
});

authenticate

This event is emitted when successful authentication occurs. The callback accepts a single argument:

• username - the username of the successfully authenticated SOCKS5 proxy user

// When authentication succeeds
server.on('authenticate', function (username) {
	console.log('user %s successfully authenticated!', username);
});

authenticateError

This event is emitted when authentication is not successful. The callback accepts the following arguments:

• username - the username of the SOCKS5 proxy user
• err - the error returned to the options.authenticate callback

// When authentication fails
server.on('authenticateError', function (username, err) {
	console.log('user %s failed to authenticate...', username);
	console.error(err);
});

proxyConnect

This event is emitted each time a connection is requested to a remote destination. The callback accepts two arguments:

• info - object with two fields
  • host - the TCP address of the remote server
  • port - the TCP port of the remote server
• destination - the destination TCP net.Socket

// When a reqest arrives for a remote destination
server.on('proxyConnect', function (info, destination) {
	console.log('connected to remote server at %s:%d', info.host, info.port);
});

proxyData

This event is emitted each time a remote connection returns data:

// When a reqest arrives for a remote destination
server.on('proxyData', function (data) {
	console.log('data received from remote destination: %d', data.length);
});

Note: This can also be accomplished by listening to the data event on the destination connection received in the proxyConnect event:

// When a reqest arrives for a remote destination
server.on('proxyConnect', function (info, destination) {
	destination.on('data', function (data) {
		console.log('data received from remote destination: %d', data.length);
	});
});

proxyError

In the event that a network error occurs attempting to create communication with the destination, this event is raised.

// When an error occurs connecting to remote destination
server.on('proxyError', function (err) {
	console.error('unable to connect to remote server');
	console.error(err);
});

proxyEnd

When a socket connection is closed by the server, the proxyEnd event is emitted. It returns two arguments in the callback:

• response - the specific RFC 1928 documented response code
• args - RFC 1928 fields for the proxy request including
  • ver
  • cmd
  • atype
  • dst.addr
  • dst.port

// When a proxy connection ends
server.on('proxyEnd', function (response, args) {
	console.log('socket closed with code %d', response);
	console.log(args);
});