Leemoonsoo/ktun

Reverse http tunnel over websocket

ktun

ktun establishes http reverse tunnels over WebScoket connections for circumventing the problem of directly connect to hosts behind a strict firewall or without public IP

• Reverse http tunnel over websocket
• Expose service running behind firewall with access token
• Http request

Usage

Use docker image moon/ktun:<version>

Setup tunnel server

Start a tunnel server (on port 8080), on publicly accessible host.

ktun -p 8080

Start tunnel

If public domain name of tunnel server is ktun.example.com, ktun client can connect the server to reverse proxy service behind firewall.

ktun -t mysecrettoken -r localhost:7777 -s ws://ktun.example.com

ktun client request a new tunnel to server (with secret token 'mysecrettoken'), and reverse proxy request from server to service behind firewall localhost:7777.

Make a request through the tunnel

$ curl 'http://ktun.example.com:8080/_ktun/my_b!g_$secret/some/web/page'
$ curl '-HX-Ktun-Token: mysecrettoken' http://wstun.example.com:8080/some/web/page

http request to http://wstun.example.com/_ktun/mysecrettoken/ will be forwarded to service running behind firewall (localhost:7777) through the tunnel.

      HTTP-client ==>\     ||firewall||     /===> HTTP-server
                     |                      | (localhost:7777)
                     \----------------------/
                Ktun     <===tunnel====    Ktun
          (tunnel-server.com)            (client)

This connection mechanism is inspired by wstunnel. However, wstunnel does not handle websocket request. This project uses wstun to create tcp tunnel over websocket and node-http-proxy to reverse proxy request. And it handles websocket connection smoothly.