pofw.js

A simple port-forwarding program written in CoffeeScript.

It is inspired by the pofw project by @m13253. This program is no more than a node.js version of the pofw project plus the statistics functionality.

It listens on some TCP(UDP) ports and forwards packets to some other hosts' TCP(UDP) ports.

Installation

To install globally

npm install -g pofw.js

To install locally

npm install pofw.js

Or you may repackage this module and install it using the package manager of your system.

Usage

Usage: pofwjs -c [config] -s [statistics] -w [port]

Options:
  -c, --config      Path to the configuration file in JSON format
                                  [required] [default: "config.json"]
  -s, --statistics  Path to the statistics file where the program
                    will write usage statistics into
                              [required] [default: "statistics.json"]
  -w, --web         Web server port for showing statistics page (0 =
                    disable)    [number] [required] [default: "8080"]
  -h, --help        Show help                               [boolean]

See the example directory for details on the configuration file.

Supported protocols

1. tcp, tcp4, tcp6
2. udp, udp4, udp6

where tcp4, tcp6 are only aliases of tcp and udp is an alias of udp4. This rule is inherited from the node.js standard library.

CONVERSION BETWEEN TCP AND UDP IS NOT SUPPORTED

Statistics

pofwjs will record the usage statistics in the file which is assigned by the -s or --statistics argument (by default it will be statistics.json in the current directory). And if the port is set to an non-zero number, say, 8080, then a web frontend will be present at 127.0.0.1:8080. Visit that address in your browser and a table with the usage statistics will be shown. The program also exposes an API /backend/reset which can reset all the statistics to 0 on receiving a GET request.

The web interface listens only on the loopback address 127.0.0.1. If you want to access it over Internet, use Nginx as a reverse proxy. Remember to set up an authentication method like HTTP basic auth at least on the /backend/ subdirectory.

The program stores the statistics in-memory and writes them into disk every minute or when killed with the signal SIGINT.

To get monthly usage statistics, you can combine the /backend/reset API with curl or similar tools and a timer utility like systemd-timer (IFTTT is a good idea too)

License

Copyright © 2016 Peter Cai <peter at typeblog dot net>
This program is free software. It comes without any warranty, to the
extent permitted by applicable law. You can redistribute it and/or
modify it under the terms of the Do What The Fuck You Want To Public
License, Version 2, as published by Sam Hocevar. See the license below
for more details.

DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
            Version 2, December 2004

Copyright (C) 2004 Sam Hocevar <[email protected]>

Everyone is permitted to copy and distribute verbatim or modified
copies of this license document, and changing it is allowed as long
as the name is changed.

    DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION

0. You just DO WHAT THE FUCK YOU WANT TO.