Add SSH local forwarding script.

#!/bin/sh

set -eu

usage () {

    echo "Usage: $0 host forward"

}

host="$1" || { usage >> /dev/stderr; exit 1; }

forward="$2" || { usage >> /dev/stderr; exit 1; }

alias ssh='ssh -fnNTS ~/.ssh/%C.sock'

if ! ssh -O check -L "$forward" "$host"

then

    ssh -o ControlMaster=auto -o ControlPersist=0 -o ExitOnForwardFailure=no -o ControlPersist=0 "$host"

    ssh -O forward -L "$forward" "$host"

fi