tun

Introduction

This is a simple and efficient reverse proxy toolkit that expose servers behind a NAT to the internet, such as accessing local web server via the internet.

Usage

Developers can import tun packages to develop their own programs, import github.com/4396/tun/server development server program, import github.com/4396/tun/client development client program.

The server program need to implement authentication and load function, prototype as follows.

// AuthFunc using id and token to authorize a proxy.
type AuthFunc func(id, token string) error

// LoadFunc using loader to load a proxy with id.
type LoadFunc func(loader Loader, id string) error

At the same time the project also provides a default implementation, located in the github.com/4396/tun/cmd, support tcp and http two types of proxy.

~ go get github.com/4396/tun/cmd/tuns
~ go get github.com/4396/tun/cmd/tunc

For example, expose the local godoc service to internet.

1. Start godoc:

   godoc -http=:9090

2. Start tuns:

   ./tuns -c tuns.ini

   # tuns.ini
   [tuns]
   addr = ServerIP:7000 # or :7000
   http = ServerIP:7070 # or :7070
   
   [godoc]
   type = http
   token = hello
   domain = godoc.mydomain.com
   

3. Start tunc:

   ./tunc -c tunc.ini

   # tunc.ini
   [tunc]
   server = ServerIP:7000
   
   [godoc]
   addr = 127.0.0.1:9090 # or :9090
   token = hello
   

   Or do not use a configuration file:

   ./tunc -server=ServerIP:7000 -id=godoc -token=hello -addr=:9090

4. Resolve A record of godoc.mydomain.com to ServerIP.

   If there are many proxies, you can resolve wildcard domain name.

5. Use nginx, not necessary.

   server {
       listen       80;
       server_name  godoc.mydomain.com;
   
       # wildcard domain name
       # server_name  ~.mydomain.com;
   
       location / {
           proxy_pass http://localhost:7070;
           proxy_set_header Host $host;
       }
   }
   

Reference

• ngrok - https://github.com/inconshreveable/ngrok
• frp - https://github.com/fatedier/frp