/etc/dhcp/dhclient-enter-hooks.d

dhclient-enter-hooks.d

Some custom Scripts to update things that depend on the WAN IP address

dnsmasq

#
#  This script is meant to be called by dhclient from /etc/dhcp/dhclient-enter-hooks.d/
#
#  It writes a config file for dnsmasq to injest for settings that are wan/isp-specific
#
#  Tips:
#   * Be careful about changing the environment since this is sourced
#   * This script fragment uses bash features
#

_dest="/etc/dnsmasq.d/isp.conf"

case "${reason}" in
    BOUND|RENEW|REBIND|REBOOT)
        _lan_ip=$(ip addr show dev lanbr | sed -n -e '1,5 s/ *inet \([0-9\.]*\).*/\1/ p')

        echo "# Do Not Edit - automatically generated\n" > "${_dest}"

        echo "alias=${new_ip_address},${_lan_ip}\n" >> "${_dest}"

        _isp_domains=$( expr match "${new_domain_name}" ".*\.\([^\.]*\.[^\.]*\)\." )
        case "${_isp_domains}" in
           "comcast.net")
                _isp_domains="comcast.net comcast.com xfinity.net xfinity.com"
                ;;
        esac

        for _isp_domain in ${_isp_domains}
        do
                for _dns_ip in ${new_domain_name_servers}
                do
                        echo "server=/${_isp_domain}/${_dns_ip}" >> "${_dest}"
                done
                unset _dns_ip
                echo "ipset=/${_isp_domain}/isp,isp6\n" >> "${_dest}"
        done

        unset _isp_domain
        unset _isp_domains
        unset _lan_ip

        systemctl restart dnsmasq.service
        ;;
esac

unset _dest

inadyn

#
#   This script is meant to be called from the /etc/dhcp/dhclient-enter-hooks.d/
#
#   It prods inadyn, if it's installed, to update public IP just assigned in the
#   dynamic DNS service(s) that inadyn is configured to upate.
#
#  Tips:
#   * Be careful about changing the environment since this is sourced
#   * This script fragment uses bash features
#

case "$reason" in
    BOUND|RENEW|REBIND|REBOOT)
        /usr/sbin/inadyn --once --foreground --syslog
        ;;
esac

smokeping

#
#   This script is meant to be called from the /etc/dhcp/dhclient-enter-hooks.d/
#   It updates a set of aliases with the first few hops as reported by traceroute
#   so that they can be included in your smokeping configuration, but will be
#   updated when the DHCP lease changes.
#
#  Tips:
#   * Be careful about changing the environment since this is sourced
#   * This script fragment uses bash features
#

logger "dhclient script: ${reason} ${new_ip_address}"

destination="/var/lib/smokeping/firsthops.inc"

case "$reason" in
    BOUND|RENEW|REBIND|REBOOT)
        gateway=$(ip route list | sed -n -e 's/default via \([0-9\.]*\) dev \(.*\)/\1/p')

        echo "@define gateway ${gateway}" > "${destination}"

        counter=1
        for hop in $(/usr/sbin/traceroute -m 4 -n 8.8.8.8 | /usr/bin/sed -n -e '2,5 s/ *[0-9] *\([0-9.]*\) .*$/\1/ p')
        do
            echo "@define hop-${counter} ${hop}"
            counter=$((counter+1))
        done >> "${destination}"
        ;;
esac