====== SSH through HTTP proxy ======

<flattr> 
uid=kerphi
title=SSH through HTTP proxy
description=This article explains how to connect to a ssh server located on the internet from a local network protected by a firewall through a HTTPS proxy. [...]
category=software
language=en
align=right
</flattr>

This article explains how to connect to a ssh server located on the internet from a local network protected by a firewall through a HTTPS proxy.

Requirement are :
  * Your firewall has to allow HTTPS connections through a proxy
  * You need to have root access to the server where ssh is listening

===== Configure the ssh server =====

The ssh daemon need to listen on 443 port. To accomplish this, just edit this file (on debian system) ''/etc/ssh/sshd_config'' and add this line :
<code>Port 443</code>
Then restart the daemon :
<code>sudo /etc/init.d/ssh restart</code>





===== Configure the client =====

I suppose you are on a Linux system (debian for example). First you have to compile the [[http://www.meadowy.org/~gotoh/projects/connect|connect binary]] which will help your ssh client to use proxies (HTTPS in our case). Then you have to configure your ssh client to tell him to use HTTPS proxy when he tries to connect to your ssh server.
  - Install the ''[[http://www.meadowy.org/~gotoh/projects/connect|connect]]'' software :
    * On debian system, just install the ''connect-proxy'' package :<code>sudo apt-get install connect-proxy</code>
    * On other Linux systems, you have to compile it :  <code>
cd /tmp/
wget http://www.meadowy.org/~gotoh/ssh/connect.c
gcc connect.c -o connect
sudo cp connect /usr/local/bin/ ; chmod +x /usr/local/bin/connect
</code>
  - Configure your ssh client. Open or create your ''~/.ssh/config'' file and add these lines :<code>
## Outside of the firewall, with HTTPS proxy
Host my-ssh-server-host.net
  ProxyCommand connect -H proxy.free.fr:3128 %h 443
## Inside the firewall (do not use proxy)
Host *
   ProxyCommand connect %h %p
</code>
  - Then pray and test the connection :<code>
ssh my-ssh-server-host.net
</code>


===== SSH to another server through the tunnel =====

For example to connect to in ssh ''github.com'' :
<code ssh>
Host github.com
  ProxyCommand=ssh my-ssh-server-host.net "/bin/nc -w1 %h %p"
</code>

~~DISCUSSION~~
{{tag>article computing linux debian ssh proxy firewall}}