dynamic dns IPV6 script for Synology

cloudflareddns6.sh

#!/bin/sh

# cloudflareddns6.sh - dynamic dns IPV6 updater module for Synology
#
# Author:
#	Cedric Mercier
#
# Version:
#	0.1
#
# Description:
#	copy to /homedirectory-USER/cloudflaredns6.sh
#	make executable (chmod +x)
#	add the following entry to task scheduler
#
#		
#	(note that URL is not actually used, DSM will pass us the variables)
#	run a rec_load_all query to get the record id
#	(see https://www.cloudflare.com/docs/client-api.html)
#
# Changelog:
#	0.2:
#		- Simplified this thing to its most basic requirements (curl + logging)
#		- Now either returns 'good' or the result (no checking for cases -- the log was always more useful anyway!)
#
# Based on Brian Schmidt Pedersen (http://blog.briped.net) gratisdns.sh

# TODO
# read addition parameters from cloudflare api calls
#

# these variables are passed by DSM
# username is your email
__USERNAME__="<YOUREMAIL>"
# password is your cloudflare API key
__PASSWORD__="<YOURAPIKEY>"
__HOSTNAME__="<YOURDOMAIM>"
__MYIP__="$(/sbin/ip -6 addr | grep inet6 | awk -F '[ \t]+|/' '{print $3}' | grep -v ^::1 | grep -v ^fe80 | head -n 1)"

# log location
__LOGFILE__="/var/log/cloudflareddns.log"

# additional parameters needed for CloudFlare
__RECTYPE6__="AAAA"
__RECID__="<YOUR-REC_ID>"
__RECNAME__="<YOUR-SUBDOMAIN>"
__TTL__="1"
__SERVICEMODE__="0"

log() {
    __LOGTIME__=$(date +"%b %e %T")
    if [ "${#}" -lt 1 ]; then
        false
    else
        __LOGMSG__="${1}"
    fi
    if [ "${#}" -lt 2 ]; then
        __LOGPRIO__=7
    else
        __LOGPRIO__=${2}
    fi

    logger -p ${__LOGPRIO__} -t "$(basename ${0})" "${__LOGMSG__}"
    echo "${__LOGTIME__} $(basename ${0}) (${__LOGPRIO__}): ${__LOGMSG__}" >> ${__LOGFILE__}
}

__URL__="https://www.cloudflare.com/api_json.html?a=rec_edit&tkn=${__PASSWORD__}&email=${__USERNAME__}&z=${__HOSTNAME__}&type=${__RECTYPE6__}&id=${__RECID__}&name=${__RECNAME__}&content=${__MYIP__}&ttl=${__TTL__}&service_mode=${__SERVICEMODE__}"

# Update DNS record:
log "Updating with ${__MYIP__}..." 7
__RESPONSE__=$(curl --silent "${__URL__}")

# Strip the result element from response json
__RESULT__=$(echo ${__RESPONSE__} | grep -o -E .result.:.[A-z]+.)

case ${__RESULT__} in
    '"result":"success"')
        __STATUS__='good'
        true
        ;;
    *)
        __STATUS__="${__RESULT__}"
        log "__RESPONSE__=${__RESPONSE__}" 5
        false
        ;;
esac
log "Status: ${__STATUS__}" 6

printf "%s" "${__STATUS__}"