Run firefox configured for a SSH Socks proxy connection that's managed by the script.

firesocks

#!/bin/bash

if [[ $# -lt 1 ]]; then
  echo "usage: $(basename ${0}) <gateway>"
  exit 1
fi

gateway=${1}
shift

ssh_pid=-1
cleanup () {
  kill ${ssh_pid}
}
trap cleanup SIGKILL SIGQUIT

# Find an open port
port=
ports_in_use=$(netstat -lnt 2>&1 | grep tcp | grep -v tcp6 | awk '{print $4}' | awk -F: '{print $2}' | xargs echo -n)
while (true)
do
  port=$(($RANDOM+2000)) #random port between 2000 and 32767+2000
  if ! [[ "${ports_in_use}" =~ "${port}" ]]
  then
    break
  fi
done

ssh -N -D${port} ${gateway} &
ssh_pid=$!

sed -i -e "s/\"network.proxy.socks_port\", [0-9]*/\"network.proxy.socks_port\", $port/" ~/.mozilla/firefox/*.socks/prefs.js
firefox -P socks $@
cleanup