Shutdown script for Netgear ReadyNAS (RN312)

shut_down_nas.bash

#!/usr/bin/env bash

set -e

function usage() {
  cat <<USAGE >&2
Usage: ${0##*/} [OPTION] [host]

Shut down the network attached server (NAS). This script has been
tested on Netgear ReadyNAS 312 (RN312).

Instead of supplying as arguments described below, the NAS parameters
can also be provided via environment variable; see in the parentheses.

Arguments:

  host  Host name or IP address of the NAS (NAS_HOST)
  -u    Username of the NAS account (NAS_USER)
  -p    Password of the NAS account (NAS_PASSWORD)
  -q    SSH port of the NAS over which rsync runs (NAS_PORT, default: 22)

Note:

This script depends on the following command(s) to be available:

  - curl
  - nc

USAGE
  exit "${1:-1}"
}


function error() {
  >&2 echo "ERROR: $1"
  exit "${2:-1}"
}


function log() {
  logger -s -t backup "$1"
}


# Check if the NAS is alive
function nas_is_alive() {
  local host=$1
  local port=$2

  if nc -w 5 -z "${host}" "${port}"; then
    return 0
  else
    return 1
  fi
}


# Get a CSRF token from the NAS
function get_token() {
  local host=$1
  local user=$2
  local password=$3
  local tf
  local token

  tf=$(mktemp)

  curl -u "$user:$password" "http://$host/admin/csrf.html" > "$tf"
  token=$(cat "$tf" | grep csrfInsert | cut -d'"' -f 4)
  rm "$tf"
  echo "$token"
}


readonly shutdown_request_body=$(cat <<-BODY
<?xml version="1.0" encoding="UTF-8"?>
<xs:nml xmlns:xs="http://www.netgear.com/protocol/transaction/NMLSchema-0.9"
        xmlns="urn:netgear:nas:readynasd"
        src="dpv_1445852944000"
        dst="nas">
  <xs:transaction id="njl_id_2269">
    <xs:custom id="njl_id_2268"
               name="Halt"
               resource-id="Shutdown"
               resource-type="System">
      <Shutdown halt="true" fsck="false"/>
    </xs:custom>
  </xs:transaction>
</xs:nml>
BODY
)


# Issue a shutdown command to the NAS
function issue_shutdown() {
  local host=$1
  local user=$2
  local password=$3
  local token=$4

  curl -u "$user:$password" \
       --retry 10 \
       -k "http://${host}/dbbroker" \
       -H "Content-Type: application/x-www-form-urlencoded;" \
       -H "X-Requested-With: XMLHttpRequest" \
       -H "csrfpid: ${token}" \
       --data "$shutdown_request_body"
}


# Shut down the NAS
function shut_down_nas() {
  local host=$1
  local port=$2
  local user=$3
  local password=$4
  local token

  while nas_is_alive "$host" "$port" ; do
    token=$(get_token "$host" "$user" "$password")
    issue_shutdown "$host" "$user" "$password" "$token"
    sleep 30
  done
}


function main() {
  local host=${NAS_HOST}
  local user=${NAS_USER}
  local password=${NAS_PASSWORD}
  local port=${NAS_PORT:-22}

  shut_down_nas "$host" "$port" "$user" "$password"
}


while getopts "hp:q:u:" opt; do
  case $opt in
    h|\?)
      if [ "$opt" = "h" ]; then usage 0; else usage; fi
      ;;
    p)
      NAS_PASSWORD=$OPTARG
      ;;
    q)
      NAS_PORT=$OPTARG
      ;;
    u)
      NAS_USER=$OPTARG
      ;;
  esac
done
shift $((OPTIND - 1))

NAS_HOST=${1:-$NAS_HOST}

main "$@"