# -*- shell-script -*-
PATH=/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin
DAEMON=/usr/sbin/dnsmasq
NAME=dnsmasq
DESC="DNS forwarder and DHCP server"
INSTANCE="${2}"

# Most configuration options in /etc/default/dnsmasq are deprecated
# but still honoured.
if [ -r /etc/default/${NAME}${INSTANCE:+.${INSTANCE}} ]; then
    . /etc/default/${NAME}${INSTANCE:+.${INSTANCE}}
fi

# Get the system locale, so that messages are in the correct language, and the
# charset for IDN is correct
if [ -r /etc/default/locale ]; then
    . /etc/default/locale
    export LANG
fi

# RESOLV_CONF:
# If the resolvconf package is installed then use the resolv conf file
# that it provides as the default.  Otherwise use /etc/resolv.conf as
# the default.
#
# If IGNORE_RESOLVCONF is set in /etc/default/dnsmasq or an explicit
# filename is set there then this inhibits the use of the resolvconf-provided
# information.
#
# Note that if the resolvconf package is installed it is not possible to
# override it just by configuration in /etc/dnsmasq.conf, it is necessary
# to set IGNORE_RESOLVCONF=yes in /etc/default/dnsmasq.

if [ ! "${RESOLV_CONF}" ] &&
   [ "${IGNORE_RESOLVCONF}" != "yes" ] &&
   [ -x /sbin/resolvconf ]
then
    RESOLV_CONF=/run/dnsmasq/resolv.conf
fi

for INTERFACE in ${DNSMASQ_INTERFACE}; do
    DNSMASQ_INTERFACES="${DNSMASQ_INTERFACES} -i ${INTERFACE}"
done

for INTERFACE in ${DNSMASQ_EXCEPT}; do
    DNSMASQ_INTERFACES="${DNSMASQ_INTERFACES} -I ${INTERFACE}"
done

if [ ! "${DNSMASQ_USER}" ]; then
    DNSMASQ_USER="dnsmasq"
fi

# This tells dnsmasq to ignore DNS requests that don't come from a local network.
# It's automatically ignored if --interface --except-interface, --listen-address
# or --auth-server exist in the configuration, so for most installations, it will
# have no effect, but for otherwise-unconfigured installations, it stops dnsmasq
# from being vulnerable to DNS-reflection attacks.

DNSMASQ_OPTS="${DNSMASQ_OPTS} --local-service"

# If the dns-root-data package is installed, then the trust anchors will be
# available in ROOT_DS, in BIND zone-file format. Reformat as dnsmasq
# --trust-anchor options.

ROOT_DS="/usr/share/dns/root.ds"

if [ -f ${ROOT_DS} ]; then
    DNSMASQ_OPTS="$DNSMASQ_OPTS `env LC_ALL=C sed -rne "s/^([.a-zA-Z0-9]+)([[:space:]]+[0-9]+)*([[:space:]]+IN)*[[:space:]]+DS[[:space:]]+/--trust-anchor=\1,/;s/[[:space:]]+/,/gp" $ROOT_DS | tr '\n' ' '`"
fi

checkconfig()
{
    ${DAEMON} --test ${CONFIG_DIR:+ -7 ${CONFIG_DIR}} ${DNSMASQ_OPTS:+ ${DNSMASQ_OPTS}} >/dev/null 2>&1
}

start_resolvconf()
{
# If interface "lo" is explicitly disabled in /etc/default/dnsmasq
# Then dnsmasq won't be providing local DNS, so don't add it to
# the resolvconf server set.
    for interface in ${DNSMASQ_EXCEPT}; do
        [ ${interface} = lo ] && return
    done

    # Also skip this if DNS functionality is disabled in /etc/dnsmasq.conf
    if grep -qs '^port=0' /etc/dnsmasq.conf; then
        return
    fi

    if [ -x /sbin/resolvconf ] ; then
        echo "nameserver 127.0.0.1" | /sbin/resolvconf -a lo.${NAME}${INSTANCE:+.${INSTANCE}}
    fi
    return 0
}

stop_resolvconf()
{
    if [ -x /sbin/resolvconf ] ; then
        /sbin/resolvconf -d lo.${NAME}${INSTANCE:+.${INSTANCE}}
    fi
    return 0
}