Quick rockin' ssh tunnel!

README

You have a VPN to work.
You have a gateway host you're required to ssh through.
You have a mac.
You want SSHing to be fast, if possible.

10.0.0.10 is a fill in for the bastion host.
My name is James.  Your name probably isn't.
10.11.12.13 is a fill in for my desktop.

If you're not connected to the VPN, it will just try and connect directly.

The ControlPersist stuff is pretty important to make things nice and fast.

ssh-to-work

!/bin/bash

# change IPSec and WORK-VPN to match your VPN settings.
# WORK-VPN is the name of the interface in your config
# IPSec or PPTP or whatever.  You can also use the UUID.

if scutil --nc list|grep IPSec|grep -F '"WORK-VPN"'|grep -q Connected ;then
    # The VPN is online.  Let's connect through ssh-gateway!
    ssh -q -oHostKeyAlias=ssh-gateway -W $1:$2 -l james 10.0.0.10
else
    ssh -q -oHostKeyAlias=james-desktop -W $1:$2 -l james 10.11.12.13
fi

ssh_config

Host *
        ControlPath ~/.ssh/controlmasters/%r@%h:%p
        ControlMaster auto
        ControlPersist 0

Host james2
        ProxyCommand ~/bin/ssh-to-work %h %p
        User james