dnsmasq

#!/usr/bin/env bash

dnsmasq_conf=/etc/dnsmasq.conf
FILE_DNSMASQ_CONFIG=${FILE_DNSMASQ_CONFIG:-/etc/dnsmasq.d/pixieboot.conf}
CMD_RELOAD_DNSMASQ=${CMD_RELOAD_DNSMASQ:-"service dnsmasq restart"}

function die(){  warn $*; exit 1; }
function warn(){ echo $* >&2; }

checksum(){
	sha1sum $* 2>/dev/null
}

checksum_old=$(checksum $FILE_DNSMASQ_CONFIG)
checksum_old_dnsmasq=$(checksum $dnsmasq_conf)

# enable config-dir option in dnsmasq.d
if ! grep -q "^\\s*conf-dir=$(dirname $FILE_DNSMASQ_CONFIG)" $dnsmasq_conf; then
	echo "conf-dir=$(dirname $FILE_DNSMASQ_CONFIG)" >> $dnsmasq_conf
fi

mkdir -p $(dirname $FILE_DNSMASQ_CONFIG)
cat > $FILE_DNSMASQ_CONFIG <<-END
# PXE Boot for dnsmasq
interface=*
dhcp-range=$NFSHOST,proxy
log-dhcp

enable-tftp
tftp-root=$NFSPREFIX
$(
if [ "$IPXE_ENABLED" != 0 ]; then
	echo "# tag all requests with 175 (iPXE) option"
	echo "dhcp-match=set:ipxe,175"
	echo "dhcp-option=175,8:1:1"
else
	 echo "dhcp-boot=$NFSPREFIX/pxelinux.0"
fi
)
dhcp-option=17,$NFSPREFIX/nfs
dhcp-option=vendor:PXEClient,6,2b
dhcp-no-override
$(
if [ "$IPXE_ENABLED" != 0 ]; then
	echo "pxe-service=tag:!ipxe,X86PC, "Network Boot", /undionly.kpxe"
	echo "pxe-service=tag:ipxe,X86PC, "Network Boot", /bootstrap.ipxe"
else
	echo "pxe-service=X86PC, "Network Boot Menu", /pxelinux"
fi
)
# neccessary to not break DNS on the host
port=53
no-resolv
server=8.8.8.8
server=8.8.4.4
END

checksum_new=$(checksum $FILE_DNSMASQ_CONFIG)
checksum_new_dnsmasq=$(checksum $dnsmasq_conf)

# Reload dnsmasq if neccessary
if [ "$checksum_old" != "$checksum_new" -o "$checksum_old_dnsmasq" != "$checksum_new_dnsmasq" ]; then
	echo "dnsmasq's configuration changed. Reloading."
	$CMD_RELOAD_DNSMASQ
fi