Turtle shell behind proxy

[boxturtle]

The network I'm attempting to use my turtle on is behind a proxy server blocking outgoing connections. I would like to connect to my VPS on the Internet through this proxy by tunneling ssh. I'm starting to think that's not currently possible... Am I missing something?

I first tried a command similar to this to tunnel using netcat:

ssh user@final_dest -o "ProxyCommand=nc -X connect -x proxyhost:proxyport %h %p"

That command fails with a message similar to this:

nc: invalid option -- X
 Try `nc --help' for more information.

Unfortunately the version of netcat doesn't support what I need to do.

Another alternative is to use corkscrew, but I don't have the ability to build for the turtle architecture and there are no compatible binaries of it available for download.

Is there a way to get through the proxy with my turtle?

[boxturtle]

Alright, I finally got around to tackling this issue... I decided to build a version of corkscrew for my turtle.

Step 1... Grab the latest buildroot for my Ubuntu system and configure it for the turtle. After issuing a 'make menuconfig', I set the following options (going off of memory here):

• Target options -> Target Architecture: MIPS (big endian)
• Toolchain ->
  • Toolchain type: Buildroot toolchain)
  • Kernel Headers: Linux 3.10.x kernel headers
  • C library: uClibc
  • uClibc C library Version: uClibc 0.9.33.x

​I left everything else the default and saved the configuration. After issuing a 'make', I was left with a toolchain that would build for MIPS.

Step 2... Build corkscrew. Since corkscrew wasn't setup to cross-compile, I just built it manually from the command-line after adding the new toolchain to my path:

mips-linux-gcc -c corkscrew.c
mips-linux-gcc -o corkscrew corkscrew.o

Step 3... scp that file to my turtle, and ssh into it to configure. After configuring the autossh module, there was one additional step to get the turtle to use corkscrew. I modified /etc/ssh/ssh_config to add an entry like this:

host myhost.example.com
  user myuser
  proxycommand /path/to/corkscrew proxy-server.example.org 8080 %h %p