protoplex

An application protocol multiplexer

What is this?

In a nutshell, this application lets you run multiple kinds of applications
on a single port. This is useful for, for instance, running an OpenVPN server
and a TLS/HTTPS server on port 443, which in turn is useful for evading
firewalls that block all other outbound ports.

Running

Native

Assuming you have a properly configured Go setup, get and compile the multiplexer with

bash
go get github.com/Pandentia/protoplex/cmd/protoplex

and then run it with (for example, to run SSH and HTTPS)

bash
protoplex --ssh your_ssh_host:22 --tls your_webserver:443

Protoplex is now running on port 8443 and ready to accept connections.

For more extensive configuration, please see the output of --help.

Docker

A docker image may be used
for ease of use and deployment.

Goals

The concepts for this multiplexer were as follows:

Resource usage about on par with sslh
Easily extensible
Highly dynamic

To this end, protoplex supports multiple matching methods for protocols:

Bytestring comparison
Regex matching

These can both be implemented for a protocol, with bytestrings taking
priority (due to efficiency). In addition, protocols support matching limits,
reducing the amount of protocols evaluated for a given handshake.

Protocol support

Currently supported protocols are:

SSH
HTTP
TLS (/ HTTPS)
OpenVPN
SOCKS4 / SOCKS5

Feel free to file an issue
on the GitHub repository if you want a protocol to be supported. Please include
steps to accurately reproduce your client setup.

Alternatively, you may submit a pull request.