In order to investigate a bug I was running into, I recently had to give my colleague ssh access to my laptop behind a firewall. The easiest way I found to do this was to create an account for him on my laptop and setup a pagekite frontend on my Linode server and a pagekite backend on my laptop.

Frontend setup

Setting up my Linode server in order to make the ssh service accessible and proxy the traffic to my laptop was fairly straightforward.

First, I had to install the pagekite package (already in Debian and Ubuntu) and open up a port on my firewall by adding the following to both /etc/network/iptables.up.rules and /etc/network/ip6tables.up.rules:

-A INPUT -p tcp --dport 10022 -j ACCEPT

Then I created a new CNAME for my server in DNS:

pagekite.fmarier.org.   3600    IN  CNAME   fmarier.org.

With that in place, I started the pagekite frontend using this command:

pagekite --clean --isfrontend --rawports=virtual --ports=10022 --domain=raw:pagekite.fmarier.org:Password1

Backend setup

After installing the pagekite and openssh-server packages on my laptop and creating a new user account:

adduser roc

I used this command to connect my laptop to the pagekite frontend:

pagekite --clean --frontend=pagekite.fmarier.org:10022 --service_on=raw/22:pagekite.fmarier.org:localhost:22:Password1

Client setup

Finally, my colleague needed to add the folowing entry to ~/.ssh/config:

Host pagekite.fmarier.org
  CheckHostIP no
  ProxyCommand /bin/nc -X connect -x %h:10022 %h %p

and install the netcat-openbsd package since other versions of netcat don't work.

On Fedora, we used netcat-openbsd-1.89 successfully, but this newer package may also work.

He was then able to ssh into my laptop via ssh roc@pagekite.fmarier.org.

Making settings permanent

I was quite happy settings things up temporarily on the command-line, but it's also possible to persist these settings and to make both the pagekite frontend and backend start up automatically at boot. See the documentation for how to do this on Debian and Fedora.

http://feeding.cloud.geek.nz/posts/letting-someone-ssh-into-your-laptop-using-pagekite/