#!/bin/bash

. /usr/lib/network/functions

# Configure logging
LOG_FACILITY="dhclient-script"

assert isset interface
assert isset reason

assert device_exists ${interface}

basename="$(basename $0)"
log DEBUG "${basename} called for interface=${interface} reason=${reason}"

# Main pitchfork.
case "${reason}" in
	MEDIUM)
		# Linux does not handle MEDIUM.
		exit 0
		;;

	PREINIT)
		# Bring up the device if it hasn't been done before.
		if ! device_is_up ${interface}; then
			log DEBUG "The interface '${interface}' does not appear to be up."

			zone_up ${interface}
		fi

		# If the use configured a delay, we will honour that.
		if [ -n "${DELAY}"  ]; then
			assert isinteger DELAY
			sleep ${DELAY}

		# If he didn't, we will try to detect is STP has brought the
		# bridge up.
		elif device_is_bridge ${interface}; then
			counter=60

			while [ ${counter} -gt 0 ]; do
				# We may end this, when the bridge is in forwarding mode.
				if bridge_is_forwarding ${interface}; then
					log DEBUG "Bridge '${interface}' is in forwarding mode."
					break
				fi

				counter=$(( ${counter} - 1 ))
				sleep 1
			done

			# Tell the daemon, that we are not ready to go on.
			if [ ${counter} -eq 0 ]; then
				log ERROR "Bridge '${interface}' is not in forwarding mode."
				log ERROR "Could not go on with getting a DHCP lease. Exiting."

				exit 1
			fi
		fi

		exit 0
		;;


	BOUND|RENEW|REBIND|REBOOT)
		# Check if the IP address has changed. If so, delete all routes and stuff.
		if [ -n "${old_ip_address}" -a "${old_ip_address}" != "${new_ip_address}" ]; then
			ipv4_flush_device ${interface}
		fi

		case "${reason}" in
			BOUND|REBOOT)
				if [ ! "${old_ip_address}" = "${new_ip_address}" ] || \
					[ ! "${old_subnet_mask}" = "${new_subnet_mask}" ] || \
					[ ! "${old_network_number}" = "${new_network_number}" ] || \
					[ ! "${old_broadcast_address}" = "${new_broadcast_address}" ] || \
					[ ! "${old_routers}" = "${new_routers}" ] || \
					[ ! "${old_interface_mtu}" = "${new_interface_mtu}" ]; then


					# Calc a prefix out of address and subnet mask.
					new_prefix="$(ipv4_get_prefix ${new_ip_address} ${new_subnet_mask})"

					# Set the new ip address.
					ip_address_add ${interface} ${new_ip_address}/${new_prefix}
					device_set_up ${interface}


					# A MTU of 576 is used for X.25 and dialup connections. Some broken DHCP
					# servers send out an MTU of 576 bytes, which will be ignored.
					if [ -n "${new_interface_mtu}" ] && [ ${new_interface_mtu} -gt 576 ]; then
						device_set_mtu ${interface} ${new_interface_mtu}
					fi

					# Save configuration
					routing_db_set ${interface} ipv4 type "ipv4-dhcp"
					routing_db_set ${interface} ipv4 local-ip-address "${new_ip_address}/${new_prefix}"
					routing_db_set ${interface} ipv4 remote-ip-address "${new_routers}"
					routing_db_set ${interface} ipv4 active 1
					routing_db_set ${interface} ipv4 domain-name "${new_domain_name}"
					routing_db_set ${interface} ipv4 domain-name-servers "${new_domain_name_servers}"
					routing_db_set ${interface} ipv4 domain-name-servers-priority "${DNS_SERVER_DYNAMIC_PRIORITY}"

					# Update the routing tables.
					routing_update ${interface} ipv4
					routing_default_update

					# Update resolv.conf
					dns_generate_resolvconf
				fi
				;;
		esac

		exit 0
		;;

	EXPIRE|FAIL|RELEASE|STOP)
		# Remove the currently configured addresses from the device.
		if [ -n "${old_ip_address}" ]; then
			ipv4_flush_device ${interface}
		fi

		routing_db_remove ${interface} ipv4
		routing_default_update

		exit 0
		;;
esac

exit 1