#!/bin/sh

die() {
    remount_ro
    echo "ERROR: $1" >&2
    exit 1
}

gen_ssh_keys() {
    unset kf x
    mkdir -p /run/storage/ssh || die 'Could not create /run/storage/ssh'
    for x in rsa ecdsa ed25519; do
        kf=/run/storage/ssh/ssh_host_${x}_key
        if [ ! -f ${kf} ]; then
            ssh-keygen -t ${x} -f ${kf} -N '' -C '' \
                || die "Failed to generate ${x} SSH host key"
        fi
    done
}

remount_ro() {
    if [ -w /run/storage ]; then
        mount -oremount,ro /run/storage
    fi
}

remount_rw() {
    if [ ! -w /run/storage ]; then
        mount -o remount,rw /run/storage \
            || die 'Could not remount /run/storage read-write'
    fi
}

mountpoint -q /run/storage || die '/run/storage is not mounted'

if [ ! -d /run/storage/ssh ]; then
    remount_rw
    gen_ssh_keys
fi

remount_ro