qtunnel is a network tunneling software working as an encryption wrapper between clients and servers (remote/local). It can work as a Stunnel/stud replacement.

qtunnel has been serving over 10 millions connections on Qu Jing each day for the past few months.

Stunnel/stud is great in SSL/TLS based environments, but what we want is a lighter and faster solution that only does one job: transfer encrypted data between servers and clients. We don't need to deal with certification settings and we want the transfer is as fast as possible. So we made qTunnel. Basically, it's a Stunnel/stud without certification settings and SSL handshakes, and it's written in Go.

qtunnel is writen in golang 1.3.1, after building it can run on almost every OS.

To build qtunnel

$ make

To test qtunnel

$ make test

$ ./bin/qtunnel -h
Usage of ./bin/qtunnel:
	-backend="127.0.0.1:6400": host:port of the backend
	-clientmode=false: if running at client mode
	-crypto="rc4": encryption method
	-listen=":9001": host:port qtunnel listen on
	-logto="stdout": stdout or syslog
	-secret="secret": password used to encrypt the data

qtunnel supports two encryption methods: rc4 and aes256cfb. Both servers and clients should use the same crypto and same secret.

Let's say, you have a redis server on host-a, you want to connect to it from host-b, normally, just use:

$ redis-cli -h host-a -p 6379

will do the job. The topology is:

redis-cli (host-b) <------> (host-a) redis-server

If the host-b is in some insecure network environment, i.e. another data center or another region, the clear-text based redis porocol is not good enough, you can use qtunnel as a secure wrapper

On host-b:

$ qtunnel -listen=127.1:6379 -backend=host-a:6378 -clientmode=true -secret=secret -crypto=rc4

On host-a:

$ qtunnel -listen=:6378 -backend=127.1:6379 -secret=secret -crypto=rc4

Then connect on host-b as:

$ redis-cli -h 127.1 -p 6379

This will establish a secure tunnel between your redis-cli and redis server, the topology is:

redis-cli (host-b) <--> qtunnel (client,host-b) <--> qtunnel (host-a) <--> redis-server

After this, you can communicate over a encrypted wrapper rather than clear text.

Special thanks to Paul for reviewing the code.

We encourage you to contribute to qtunnel! Please feel free to submit a bug report, fork the repo or create a pull request.

qtunnel is released under the Apache License 2.0.