# Update Hurricane Electric IPv6 Tunnel Client IPv4 address
# This is an upgrade to an existing script from
# http://wiki.mikrotik.com/wiki/Hurricane_Electric_IPv6_Tunnel_-_IPv4_Endpoint_updater
# API call format:
# https://#USERNAME:$API_KEY@ipv4.tunnelbroker.net/nic/update?username=$USERNAME&password=$API_KEY&hostname=$TUNNEL_ID
# ----------------------------------
# Modify the following to match your parameters
# ----------------------------------

# Router's WAN interface name
:local WANinterface "ppoe-1"

# Router's 6to4 interface name
:local HEtunnelinterface "sit1"

# Your username - you use it to log in at https://tunnelbroker.net
:local HEuserid "NAME"

# Tunnel ID (not name) as written in your tunnel's details at https://tunnelbroker.net
:local HEtunnelid "00000"

# Your Update Key for this tunnel, as written in the "Advanced" tab on tunnel details page
:local HEkey "AAAAAAAAAAAAAA"

# ----------------------------------
# STOP modifying here
# ----------------------------------
# Internal processing below...
# ----------------------------------
:local HEupdatehost "ipv4.tunnelbroker.net"
:local HEupdatepath "/nic/update?"
:local outputfile ("HE-" . $HEtunnelid . ".txt")
:local HEipv4addr

# Get WAN interface IP address
:set HEipv4addr [/ip address get [/ip address find interface=$WANinterface] address]
:set HEipv4addr [:pick [:tostr $HEipv4addr] 0 [:find [:tostr $HEipv4addr] "/"]]

:if ([:len $HEipv4addr] = 0) do={
   :log error ("Could not get IP for interface " . $WANinterface)
   :error ("Could not get IP for interface " . $WANinterface)
}

# Update the HEtunnelinterface with WAN IP
/interface 6to4 {
    :if ([get ($HEtunnelinterface) local-address] != $HEipv4addr) do={
        :log info ("Updating IPv6 Tunnel " . $HEtunnelid . " Client IPv4 address to new IP " . $HEipv4addr . "...")
        disable $HEtunnelinterface

        /tool fetch mode=https host=($HEupdatehost) url=("https://" . $HEuserid . ":" . $HEkey . "@" . $HEupdatehost . $HEupdatepath . "&username=" . $HEuserid . "&pass=" . $HEkey . "&hostname=" . $HEtunnelid) dst-path=($outputfile)

        # Change the client IPv4 address
        set ($HEtunnelinterface) local-address=$HEipv4addr

        # I like to make a little pause before enabling the interface
        /delay 3
        
        # Enable the IPv6 interface
        enable $HEtunnelinterface 

        # Append the file to log for review
        :log info ([/file get ($outputfile) contents])
        
        # Clean up after ourselves
        /file remove ($outputfile)
        
    } else={
        # If client's IPv4 didn't change at all, put it in the log so that we know the script is working
        :log info ("Updating " . $HEtunnelinterface . " No change, IP is still " . $HEipv4addr )
    }   
}