/htunnel

HTTP tunnel

Primary LanguageJavaApache License 2.0Apache-2.0

htunnel

A simple HTTP Tunnel written in Java to encapsulate any TCP/IP connection and pass through HTTP proxies.

It is typically used to perform SSH connections behind a corporate HTTP proxy that does not accept CONNECT method.

It consists of a client module (htunnel-client) to be installed in the private network behind the HTTP proxy and a server module (htunnel-server) to be installed anywere on the Internet.

 ----------------------------------------------------------------   -----------------------------------------------
| Corporate Network                                              | | Internet                                      | 
|                                                                | |                                               |
|  --------------------------------------------                  | |                                               |
| | Employee PC                                |                 | |                                               |
| |                                            |                                                                   |
| |  ------------   TCP/IP   ----------------  | HTTP   -------  HTTP   ----------------   TCP/IP   ------------   |
| | | SSH Client |--------->| htunnel-client |-------->| Proxy |------>| htunnel-server |--------->| SSH Server |  |
| |  ------------            ----------------  |        -------         ----------------            ------------   |
| |                                            |                 | |                                               |
|  --------------------------------------------                  | |                                               |
|                                                                | |                                               |
 ----------------------------------------------------------------   -----------------------------------------------

Build

The source code is written in Java and can be built with Apache Maven. Perform the following command in the root directory:

mvn clean install

This will produce 2 jar files:

  • htunnel-client/target/htunnel-client-version.jar
  • htunnel-server/target/htunnel-server-version.jar

Usage

htunnel-server

Run htunnel-server on any machine in the Internet:

java -jar htunnel-server-version.jar

It will start a HTTP server on port 8080.

You can change port number with option --server.port:

java -jar htunnel-server-version.jar --server.port=80

htunnel-client

Run htunnel-client on any machine in the corporate network:

java -jar htunnel-client-version.jar --target=sshhost:sshport --tunnel=http://tunnelhost:8080/ --proxy=http://proxyhost:proxyport/

It will start the client daemon on port 3000. Any communication made with htunnel client will be transferred to the specified target.

You can change port number with option --port:

java -jar htunnel-client-version.jar --port=4000 --target=sshhost:sshport --tunnel=http://tunnelhost:8080/ --proxy=http://proxyhost:proxyport/

If the proxy requires authentication you can specify a user and password in the proxy url: --proxy=http://username:pasword@proxyhost:proxyport/

Finally perform SSH connection:

ssh -p 3000 localhost