#!/bin/sh
#
Domain=domain1.jp
MasterID=mydnsXXXXXX
Password=xxxxxxxxxxx
IfName=eth0

ipv4=0
ipv6=0
ip -o addr show | while read num ifname inet ipaddr other
do
  test "$ifname" != "$IfName" && continue
  echo $other | grep "scope global" > /dev/null || continue
  echo $other | grep "mngtmpaddr" > /dev/null && continue
  case $inet
  in
    inet6)
      URL="https://ipv6.mydns.jp/directip.html?MID=${MasterID}&PWD=${Password}&IPV6ADDR=${ipaddr%/*}"
      if [ ${ipv6} -eq 0 ]
      then
        curl ${URL} -o /dev/null 1> /dev/null 2>&1 && ipv6=1
        ans=`dig $Domain AAAA +short`
        logger -p user.info -t mydns "Status ifname=${ifname}, ${inet}=${ipaddr}, Ans=${ans}, Update=${ipv6}"
      fi
      ;;
    inet)
      URL="https://${MasterID}:${Password}@www.mydns.jp/login.html"
      if [ ${ipv4} -eq 0 ]
      then
        curl ${URL} -o /dev/null 1> /dev/null 2>&1 && ipv4=1
        ans=`dig $Domain A +short`
        logger -p user.info -t mydns "Status ifname=${ifname}, ${inet}=${ipaddr}, Ans=${ans}, Update=${ipv4}"
      fi
      ;;
  esac
done