#!/bin/sh

set -eu

img="$1"
shift

undo() {
    umount --force "$tmp" || true
    rmdir "$tmp"
    kpartx -dsv "$img"
}

trap undo EXIT
tmp="$(mktemp -d)"

dev="/dev/mapper/$(kpartx -asv "$img" | awk '{ print $3 }')"
mount "$dev" "$tmp"
cat "$@" > "$tmp/home/manager/.ssh/authorized_keys"