wstunnel

Establish a TCP socket tunnel over web socket connection, for circumventing strict firewalls.

Installation

npm install wstunnel

Usage

Run the websocket tunnel server at port 8080:

wstunnel -s 8080

Run the websocket tunnel client:

wstunnel -tunnel 33:2.2.2.2:33 ws://host:8080

In the above example, client picks the final tunnel destination, similar to ssh tunnel. Alternatively for security reason, you can lock tunnel destination on the server end, example:

Server:
    wstunnel -s 8080 -t 2.2.2.2:33

Client:
    wstunnel -t 33 ws://server:8080

In both examples, connection to localhost:33 on client will be tunneled to 2.2.2.2:33 on server via websocket connection in between.

To tell client to connect via http proxy, do:

wstunnel -t 33:2.2.2.2:33 -p http://[user:pass@]proxyhost:proxyport wss://server:443

When connecting to secure websocket server via "wss://", client might want to disable 'unauthorized' certificate rejection, via adding the '-c' option.

wstunnel -t 33:2.2.2.2:33 -c -p http://[user:pass@]proxyhost:proxyport wss://server:443

This also makes you vulnerable to MITM attack, so use with caution.

To get help, just run

wstunnel

Use case

For tunneling over strict firewalls: WebSocket is a part of the HTML5 standard, any reasonable firewall will unlikely be so strict as to break HTML5.

The tunnel server currently supports plain tcp socket only, for SSL support, use NGINX, shown below:

On server: wstunnel -s 8080

On server, run nginx (>=1.3.13) with sample configuration:

server {
    listen   443;
    server_name  mydomain.com;

    ssl  on;
    ssl_certificate  /path/to/my.crt
    ssl_certificate_key  /path/to/my.key
    ssl_session_timeout  5m;
    ssl_protocols  SSLv2 SSLv3 TLSv1;
    ssl_ciphers  ALL:!ADH:!EXPORT56:RC4+RSA:+HIGH:+MEDIUM:+LOW:+SSLv2:+EXP;
    ssl_prefer_server_ciphers   on;

    location / {
        proxy_pass http://127.0.0.1:8080;
        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection "upgrade";
        proxy_set_header        Host            $host;
        proxy_set_header        X-Real-IP       $remote_addr;
        proxy_set_header        X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header        X-Forwarded-Proto $scheme;
    }
}

Then on client:

wstunnel -t 99:targethost:targetport wss://mydomain.com

OpenVPN use case

Suppose on the server you have OpenVpn installed on the default port 1194, then run wstunnel as such:

wstunnel -s 8888 -t 127.0.0.1:1194

Now on the server, you have a websocket server listening on 8888, any connection to 8888 will be forwarded to
127.0.0.1:1194, the OpenVpn port.

Now on client, you run:

wstunnel -t 1194 ws://server:8888

Then launch the OpenVpn client, connect to localhost:1194 will be same as connect to server's 1194 port.

This setup won't work if you are behind a strict firewall because:

1. Non 80/443 ports are usually blocked by firewall.
2. Stateful packet inspection will detect the content of your websocket tunnel, for example OPENVPN connection, or SSH connection, and then block it anyways.

But the following setup works universally:

1. Run wstunnel server mode

    wstunnel -s 8888 -t 127.0.0.1:1194
       

2. Run NGINX on server, listen on 443 for https connection, forward to wstunnel server localhost:8888

3. On client, run wstunnel client mode using "wss://"

    wstunnel -t 1194 wss://server

4. Now on client, launch OPENVPN connection to localhost:1194, it will work.

The only possible way for above setup to not work is that your server is blacklisted by the firewall.