#!/bin/bash
#
# dhclient-script: Network interface configuration script run by
# dhclient based on DHCP client communication
#
# Copyright (C) 2008-2014 Red Hat, Inc.
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
#
# Author(s): David Cantrell <dcantrell@redhat.com>
# Jiri Popelka <jpopelka@redhat.com>
#
# ----------
# This script is a rewrite/reworking on dhclient-script originally
# included as part of dhcp-970306:
# dhclient-script for Linux. Dan Halbert, March, 1997.
# Updated for Linux 2.[12] by Brian J. Murrell, January 1999.
# Modified by David Cantrell <dcantrell@redhat.com> for Fedora and RHEL
# ----------
#
PATH=/bin:/usr/bin:/sbin
# scripts in dhclient.d/ use $SAVEDIR (#833054)
SAVEDIR=/var/lib/dhclient
LOGFACILITY="local7"
LOGLEVEL="notice"
ETCDIR="/etc/dhcp"
logmessage() {
msg="${1}"
logger -p ${LOGFACILITY}.${LOGLEVEL} -t "NET" "dhclient: ${msg}"
}
eventually_add_hostnames_domain_to_search() {
# For the case when hostname for this machine has a domain that is not in domain_search list
# 1) get a hostname with `ipcalc --hostname` or `hostname`
# 2) get the domain from this hostname
# 3) add this domain to search line in resolv.conf if it's not already
# there (domain list that we have recently added there is a parameter of this function)
# We can't do this directly when generating resolv.conf in make_resolv_conf(), because
# we need to first save the resolv.conf with obtained values before we can call `ipcalc --hostname`.
# See bug 637763
search="${1}"
if need_hostname; then
status=1
if [ -n "${new_ip_address}" ]; then
eval $(/bin/ipcalc --silent --hostname ${new_ip_address} ; echo "status=$?")
elif [ -n "${new_ip6_address}" ]; then
eval $(/bin/ipcalc --silent --hostname ${new_ip6_address} ; echo "status=$?")
fi
if [ ${status} -eq 0 ]; then
domain=$(echo $HOSTNAME | cut -s -d "." -f 2-)
fi
else
domain=$(hostname 2>/dev/null | cut -s -d "." -f 2-)
fi
if [ -n "${domain}" ] &&
[ ! "${domain}" = "localdomain" ] &&
[ ! "${domain}" = "localdomain6" ] &&
[ ! "${domain}" = "(none)" ] &&
[[ ! "${domain}" = *\ * ]]; then
is_in="false"
for s in ${search}; do
if [ "${s}" = "${domain}" ] ||
[ "${s}" = "${domain}." ]; then
is_in="true"
fi
done
if [ "${is_in}" = "false" ]; then
# Add domain name to search list (#637763)
sed -i -e "s/${search}/${search} ${domain}/" /etc/resolv.conf
fi
fi
}
make_resolv_conf() {
[ "${PEERDNS}" = "no" ] && return
if [ "${reason}" = "RENEW" ] &&
[ "${new_domain_name}" = "${old_domain_name}" ] &&
[ "${new_domain_name_servers}" = "${old_domain_name_servers}" ]; then
return
fi
if [ -n "${new_domain_name}" ] ||
[ -n "${new_domain_name_servers}" ] ||
[ -n "${new_domain_search}" ]; then
rscf="$(mktemp ${TMPDIR:-/tmp}/XXXXXX)"
[[ -z "${rscf}" ]] && return
echo "; generated by /usr/sbin/dhclient-script" > ${rscf}
if [ -n "${SEARCH}" ]; then
search="${SEARCH}"
else
if [ -n "${new_domain_search}" ]; then
# Remove instaces of \032 (#450042)
search="${new_domain_search//\\032/ }"
elif [ -n "${new_domain_name}" ]; then
# Note that the DHCP 'Domain Name Option' is really just a domain
# name, and that this practice of using the domain name option as
# a search path is both nonstandard and deprecated.
search="${new_domain_name}"
fi
fi
if [ -n "${search}" ]; then
echo "search ${search}" >> $rscf
fi
if [ -n "${RES_OPTIONS}" ]; then
echo "options ${RES_OPTIONS}" >> ${rscf}
fi
for nameserver in ${new_domain_name_servers} ; do
echo "nameserver ${nameserver}" >> ${rscf}
done
change_resolv_conf ${rscf}
rm -f ${rscf}
if [ -n "${search}" ]; then
eventually_add_hostnames_domain_to_search "${search}"
fi
elif [ -n "${new_dhcp6_name_servers}" ] ||
[ -n "${new_dhcp6_domain_search}" ]; then
rscf="$(mktemp ${TMPDIR:-/tmp}/XXXXXX)"
[[ -z "${rscf}" ]] && return
echo "; generated by /usr/sbin/dhclient-script" > ${rscf}
if [ -n "${SEARCH}" ]; then
search="${SEARCH}"
else
if [ -n "${new_dhcp6_domain_search}" ]; then
search="${new_dhcp6_domain_search//\\032/ }"
fi
fi
if [ -n "${search}" ]; then
echo "search ${search}" >> $rscf
fi
if [ -n "${RES_OPTIONS}" ]; then
echo "options ${RES_OPTIONS}" >> ${rscf}
fi
shopt -s nocasematch
for nameserver in ${new_dhcp6_name_servers} ; do
# If the nameserver has a link-local address
# add a <zone_id> (interface name) to it.
if [[ "$nameserver" =~ ^fe80:: ]]
then
zone_id="%${interface}"
else
zone_id=
fi
echo "nameserver ${nameserver}$zone_id" >> ${rscf}
done
shopt -u nocasematch
change_resolv_conf ${rscf}
rm -f ${rscf}
if [ -n "${search}" ]; then
eventually_add_hostnames_domain_to_search "${search}"
fi
fi
}
exit_with_hooks() {
exit_status="${1}"
if [ -x ${ETCDIR}/dhclient-exit-hooks ]; then
. ${ETCDIR}/dhclient-exit-hooks
fi
exit ${exit_status}
}
quad2num() {
if [ $# -eq 4 ]; then
let n="${1} << 24 | ${2} << 16 | ${3} << 8 | ${4}"
echo "${n}"
return 0
else
echo "0"
return 1
fi
}
ip2num() {
IFS="." quad2num ${1}
}
num2ip() {
let n="${1}"
let o1="(n >> 24) & 0xff"
let o2="(n >> 16) & 0xff"
let o3="(n >> 8) & 0xff"
let o4="n & 0xff"
echo "${o1}.${o2}.${o3}.${o4}"
}
get_network_address() {
# get network address for the given IP address and (netmask or prefix)
ip="${1}"
nm="${2}"
if [ -n "${ip}" -a -n "${nm}" ]; then
if [[ "${nm}" = *.* ]]; then
ipcalc -s -n ${ip} ${nm} | cut -d '=' -f 2
else
ipcalc -s -n ${ip}/${nm} | cut -d '=' -f 2
fi
fi
}
get_prefix() {
# get prefix for the given IP address and mask
ip="${1}"
nm="${2}"
if [ -n "${ip}" -a -n "${nm}" ]; then
ipcalc -s -p ${ip} ${nm} | cut -d '=' -f 2
fi
}
class_bits() {
let ip=$(IFS='.' ip2num $1)
let bits=32
let mask='255'
for ((i=0; i <= 3; i++, 'mask<<=8')); do
let v='ip&mask'
if [ "$v" -eq 0 ] ; then
let bits-=8
else
break
fi
done
echo $bits
}
is_router_reachable() {
# handle DHCP servers that give us a router not on our subnet
router="${1}"
routersubnet="$(get_network_address ${router} ${new_subnet_mask})"
mysubnet="$(get_network_address ${new_ip_address} ${new_subnet_mask})"
if [ ! "${routersubnet}" = "${mysubnet}" ]; then
ip -4 route replace ${router}/32 dev ${interface}
if [ "$?" -ne 0 ]; then
logmessage "failed to create host route for ${router}"
return 1
fi
fi
return 0
}
add_default_gateway() {
router="${1}"
if is_router_reachable ${router} ; then
metric=""
if [ $# -gt 1 ] && [ ${2} -gt 0 ]; then
metric="metric ${2}"
fi
ip -4 route replace default via ${router} dev ${interface} ${metric}
if [ $? -ne 0 ]; then
logmessage "failed to create default route: ${router} dev ${interface} ${metric}"
return 1
else
return 0
fi
fi
return 1
}
execute_client_side_configuration_scripts() {
# execute any additional client side configuration scripts we have
if [ "${1}" == "config" ] || [ "${1}" == "restore" ]; then
for f in ${ETCDIR}/dhclient.d/*.sh ; do
if [ -x ${f} ]; then
subsystem="${f%.sh}"
subsystem="${subsystem##*/}"
. ${f}
"${subsystem}_${1}"
fi
done
fi
}
flush_dev() {
# Instead of bringing the interface down (#574568)
# explicitly clear the ARP cache and flush all addresses & routes.
ip -4 addr flush dev ${1} >/dev/null 2>&1
ip -4 route flush dev ${1} >/dev/null 2>&1
ip -4 neigh flush dev ${1} >/dev/null 2>&1
}
dhconfig() {
if [ -n "${old_ip_address}" ] && [ -n "${alias_ip_address}" ] &&
[ ! "${alias_ip_address}" = "${old_ip_address}" ]; then
# possible new alias, remove old alias first
ip -4 addr del ${old_ip_address} dev ${interface} label ${interface}:0
fi
if [ -n "${old_ip_address}" ] &&
[ ! "${old_ip_address}" = "${new_ip_address}" ]; then
# IP address changed. Delete all routes, and clear the ARP cache.
flush_dev ${interface}
fi
if [ "${reason}" = "BOUND" ] || [ "${reason}" = "REBOOT" ] ||
[ ! "${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
ip -4 addr add ${new_ip_address}/${new_prefix} broadcast ${new_broadcast_address} dev ${interface} \
valid_lft ${new_dhcp_lease_time} preferred_lft ${new_dhcp_lease_time} >/dev/null 2>&1
ip link set dev ${interface} up
# The 576 MTU is only used for X.25 and dialup connections
# where the admin wants low latency. Such a low MTU can cause
# problems with UDP traffic, among other things. As such,
# disallow MTUs from 576 and below by default, so that broken
# MTUs are ignored, but higher stuff is allowed (1492, 1500, etc).
if [ -n "${new_interface_mtu}" ] && [ ${new_interface_mtu} -gt 576 ]; then
ip link set dev ${interface} mtu ${new_interface_mtu}
fi
# static routes
if [ -n "${new_classless_static_routes}" ] ||
[ -n "${new_static_routes}" ]; then
if [ -n "${new_classless_static_routes}" ]; then
IFS=', |' static_routes=(${new_classless_static_routes})
else
IFS=', |' static_routes=(${new_static_routes})
fi
route_targets=()
for((i=0; i<${#static_routes[@]}; i+=2)); do
target=${static_routes[$i]}
if [ -n "${new_classless_static_routes}" ]; then
if [ ${target} = "0" ]; then
# If the DHCP server returns both a Classless Static Routes option and
# a Router option, the DHCP client MUST ignore the Router option. (RFC3442)
new_routers=""
prefix="0"
else
prefix=${target%%.*}
target=${target#*.}
IFS="." target_arr=(${target})
unset IFS
((pads=4-${#target_arr[@]}))
for j in $(seq $pads); do
target="${target}.0"
done
# Client MUST zero any bits in the subnet number where the corresponding bit in the mask is zero.
# In other words, the subnet number installed in the routing table is the logical AND of
# the subnet number and subnet mask given in the Classless Static Routes option. (RFC3442)
target="$(get_network_address ${target} ${prefix})"
fi
else
prefix=$(class_bits ${target})
fi
gateway=${static_routes[$i+1]}
# special case 0.0.0.0 to allow static routing for link-local addresses
# (including IPv4 multicast) which will not have a next-hop (#769463, #787318)
if [ "${gateway}" = "0.0.0.0" ]; then
valid_gateway=0
scope='scope link'
else
is_router_reachable ${gateway}
valid_gateway=$?
scope=''
fi
if [ ${valid_gateway} -eq 0 ]; then
metric=''
for t in ${route_targets[@]}; do
if [ ${t} = ${target} ]; then
if [ -z "${metric}" ]; then
metric=1
else
((metric=metric+1))
fi
fi
done
if [ -n "${metric}" ]; then
metric="metric ${metric}"
fi
ip -4 route replace ${target}/${prefix} proto static via ${gateway} dev ${interface} ${metric} ${scope}
if [ $? -ne 0 ]; then
logmessage "failed to create static route: ${target}/${prefix} via ${gateway} dev ${interface} ${metric}"
else
route_targets=(${route_targets[@]} ${target})
fi
fi
done
fi
# gateways
if [[ ( "${DEFROUTE}" != "no" ) &&
(( -z "${GATEWAYDEV}" ) || ( "${GATEWAYDEV}" = "${interface}" )) ]]; then
if [[ ( -z "$GATEWAY" ) ||
(( -n "$DHCLIENT_IGNORE_GATEWAY" ) && ( "$DHCLIENT_IGNORE_GATEWAY" = [Yy]* )) ]]; then
metric="${METRIC:-}"
let i="${METRIC:-0}"
default_routers=()
for router in ${new_routers} ; do
added_router=-
for r in ${default_routers[@]} ; do
if [ "${r}" = "${router}" ]; then
added_router=1
fi
done
if [ -z "${router}" ] ||
[ "${added_router}" = "1" ] ||
[ $(IFS=. ip2num ${router}) -le 0 ] ||
[[ ( "${router}" = "${new_broadcast_address}" ) &&
( "${new_subnet_mask}" != "255.255.255.255" ) ]]; then
continue
fi
default_routers=(${default_routers[@]} ${router})
add_default_gateway ${router} ${metric}
let i=i+1
metric=${i}
done
elif [ -n "${GATEWAY}" ]; then
routersubnet=$(get_network_address ${GATEWAY} ${new_subnet_mask})
mysubnet=$(get_network_address ${new_ip_address} ${new_subnet_mask})
if [ "${routersubnet}" = "${mysubnet}" ]; then
ip -4 route replace default via ${GATEWAY} dev ${interface}
fi
fi
fi
else # RENEW||REBIND - only update address lifetimes
ip -4 addr change ${new_ip_address}/${new_prefix} broadcast ${new_broadcast_address} dev ${interface} \
valid_lft ${new_dhcp_lease_time} preferred_lft ${new_dhcp_lease_time} >/dev/null 2>&1
fi
if [ ! "${new_ip_address}" = "${alias_ip_address}" ] &&
[ -n "${alias_ip_address}" ]; then
# Reset the alias address (fix: this should really only do this on changes)
ip -4 addr flush dev ${interface} label ${interface}:0 >/dev/null 2>&1
ip -4 addr add ${alias_ip_address}/${alias_prefix} broadcast ${alias_broadcast_address} dev ${interface} label ${interface}:0
ip -4 route replace ${alias_ip_address}/32 dev ${interface}
fi
# After dhclient brings an interface UP with a new IP address, subnet mask,
# and routes, in the REBOOT/BOUND states -> search for "dhclient-up-hooks".
if [ "${reason}" = "BOUND" ] || [ "${reason}" = "REBOOT" ] ||
[ ! "${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
if [ -x ${ETCDIR}/dhclient-${interface}-up-hooks ]; then
. ${ETCDIR}/dhclient-${interface}-up-hooks
elif [ -x ${ETCDIR}/dhclient-up-hooks ]; then
. ${ETCDIR}/dhclient-up-hooks
fi
fi
make_resolv_conf
if [ -n "${new_host_name}" ] && need_hostname; then
hostname ${new_host_name} || echo "See -nc option in dhclient(8) man page."
fi
if [[ ( "${DHCP_TIME_OFFSET_SETS_TIMEZONE}" = [yY1]* ) &&
( -n "${new_time_offset}" ) ]]; then
# DHCP option "time-offset" is requested by default and should be
# handled. The geographical zone abbreviation cannot be determined
# from the GMT offset, but the $ZONEINFO/Etc/GMT$offset file can be
# used - note: this disables DST.
((z=new_time_offset/3600))
((hoursWest=$(printf '%+d' $z)))
if (( $hoursWest < 0 )); then
# tzdata treats negative 'hours west' as positive 'gmtoff'!
((hoursWest*=-1))
fi
tzfile=/usr/share/zoneinfo/Etc/GMT$(printf '%+d' ${hoursWest})
if [ -e ${tzfile} ]; then
cp -fp ${tzfile} /etc/localtime
touch /etc/localtime
fi
fi
execute_client_side_configuration_scripts "config"
}
# Section 18.1.8. (Receipt of Reply Messages) of RFC 3315 says:
# The client SHOULD perform duplicate address detection on each of
# the addresses in any IAs it receives in the Reply message before
# using that address for traffic.
add_ipv6_addr_with_DAD() {
ip -6 addr add ${new_ip6_address}/${new_ip6_prefixlen} \
dev ${interface} scope global valid_lft ${new_max_life} \
preferred_lft ${new_preferred_life}
# repeatedly test whether newly added address passed
# duplicate address detection (DAD)
for i in $(seq 5); do
sleep 1 # give the DAD some time
addr=$(ip -6 addr show dev ${interface} \
| grep ${new_ip6_address}/${new_ip6_prefixlen})
# tentative flag == DAD is still not complete
tentative=$(echo "${addr}" | grep tentative)
# dadfailed flag == address is already in use somewhere else
dadfailed=$(echo "${addr}" | grep dadfailed)
if [ -n "${dadfailed}" ] ; then
# address was added with valid_lft/preferred_lft 'forever', remove it
ip -6 addr del ${new_ip6_address}/${new_ip6_prefixlen} dev ${interface}
exit_with_hooks 3
fi
if [ -z "${tentative}" ] ; then
if [ -n "${addr}" ]; then
# DAD is over
return 0
else
# address was auto-removed (or not added at all)
exit_with_hooks 3
fi
fi
done
return 0
}
dh6config() {
if [ -n "${old_ip6_prefix}" ] ||
[ -n "${new_ip6_prefix}" ]; then
echo Prefix ${reason} old=${old_ip6_prefix} new=${new_ip6_prefix}
exit_with_hooks 0
fi
case "${reason}" in
BOUND6)
if [ -z "${new_ip6_address}" ] ||
[ -z "${new_ip6_prefixlen}" ]; then
exit_with_hooks 2
fi
add_ipv6_addr_with_DAD
make_resolv_conf
;;
RENEW6|REBIND6)
if [[ -n "${new_ip6_address}" ]] &&
[[ -n "${new_ip6_prefixlen}" ]]; then
if [[ ! "${new_ip6_address}" = "${old_ip6_address}" ]]; then
add_ipv6_addr_with_DAD
else # only update address lifetimes
ip -6 addr change ${new_ip6_address}/${new_ip6_prefixlen} \
dev ${interface} scope global valid_lft ${new_max_life} \
preferred_lft ${new_preferred_life}
fi
fi
if [ ! "${new_dhcp6_name_servers}" = "${old_dhcp6_name_servers}" ] ||
[ ! "${new_dhcp6_domain_search}" = "${old_dhcp6_domain_search}" ]; then
make_resolv_conf
fi
;;
DEPREF6)
if [ -z "${new_ip6_prefixlen}" ]; then
exit_with_hooks 2
fi
ip -6 addr change ${new_ip6_address}/${new_ip6_prefixlen} \
dev ${interface} scope global preferred_lft 0
;;
esac
execute_client_side_configuration_scripts "config"
}
#
# ### MAIN
#
if [ -x ${ETCDIR}/dhclient-enter-hooks ]; then
exit_status=0
# dhclient-enter-hooks can abort dhclient-script by setting
# the exit_status variable to a non-zero value
. ${ETCDIR}/dhclient-enter-hooks
if [ ${exit_status} -ne 0 ]; then
exit ${exit_status}
fi
fi
if [ ! -r /etc/sysconfig/network-scripts/network-functions ]; then
echo "Missing /etc/sysconfig/network-scripts/network-functions, exiting." >&2
exit 1
fi
if [ ! -r /etc/rc.d/init.d/functions ]; then
echo "Missing /etc/rc.d/init.d/functions, exiting." >&2
exit 1
fi
. /etc/sysconfig/network-scripts/network-functions
. /etc/rc.d/init.d/functions
if [ -f /etc/sysconfig/network ]; then
. /etc/sysconfig/network
fi
if [ -f /etc/sysconfig/networking/network ]; then
. /etc/sysconfig/networking/network
fi
cd /etc/sysconfig/network-scripts
CONFIG="${interface}"
need_config ${CONFIG}
source_config >/dev/null 2>&1
new_prefix="$(get_prefix ${new_ip_address} ${new_subnet_mask})"
old_prefix="$(get_prefix ${old_ip_address} ${old_subnet_mask})"
alias_prefix="$(get_prefix ${alias_ip_address} ${alias_subnet_mask})"
case "${reason}" in
MEDIUM|ARPCHECK|ARPSEND)
# Do nothing
exit_with_hooks 0
;;
PREINIT)
if [ -n "${alias_ip_address}" ]; then
# Flush alias, its routes will disappear too.
ip -4 addr flush dev ${interface} label ${interface}:0 >/dev/null 2>&1
fi
# upstream dhclient-script removes (ifconfig $interface 0 up) old adresses in PREINIT,
# but we sometimes (#125298) need (for iSCSI/nfs root to have a dhcp interface) to keep the existing ip
# flush_dev ${interface}
ip link set dev ${interface} up
if [ -n "${DHCLIENT_DELAY}" ] && [ ${DHCLIENT_DELAY} -gt 0 ]; then
# We need to give the kernel some time to get the interface up.
sleep ${DHCLIENT_DELAY}
fi
exit_with_hooks 0
;;
PREINIT6)
# ensure interface is up
ip link set dev ${interface} up
# remove any stale addresses from aborted clients
ip -6 addr flush dev ${interface} scope global permanent
# we need a link-local address to be ready (not tentative)
for i in $(seq 50); do
linklocal=$(ip -6 addr show dev ${interface} scope link)
# tentative flag means DAD is still not complete
tentative=$(echo "${linklocal}" | grep tentative)
[[ -n "${linklocal}" && -z "${tentative}" ]] && exit_with_hooks 0
sleep 0.1
done
exit_with_hooks 0
;;
BOUND|RENEW|REBIND|REBOOT)
if [ -z "${interface}" ] || [ -z "${new_ip_address}" ]; then
exit_with_hooks 2
fi
if arping -D -q -c2 -I ${interface} ${new_ip_address}; then
dhconfig
exit_with_hooks 0
else # DAD failed, i.e. address is already in use
ARP_REPLY=$(arping -D -c2 -I ${interface} ${new_ip_address} | grep reply | awk '{print toupper($5)}' | cut -d "[" -f2 | cut -d "]" -f1)
OUR_MACS=$(ip link show | grep link | awk '{print toupper($2)}' | uniq)
if [[ "${OUR_MACS}" = *"${ARP_REPLY}"* ]]; then
# in RENEW the reply can come from our system, that's OK
dhconfig
exit_with_hooks 0
else
exit_with_hooks 1
fi
fi
;;
BOUND6|RENEW6|REBIND6|DEPREF6)
dh6config
exit_with_hooks 0
;;
EXPIRE6|RELEASE6|STOP6)
if [ -z "${old_ip6_address}" ] || [ -z "${old_ip6_prefixlen}" ]; then
exit_with_hooks 2
fi
ip -6 addr del ${old_ip6_address}/${old_ip6_prefixlen} \
dev ${interface}
execute_client_side_configuration_scripts "restore"
if [ -x ${ETCDIR}/dhclient-${interface}-down-hooks ]; then
. ${ETCDIR}/dhclient-${interface}-down-hooks
elif [ -x ${ETCDIR}/dhclient-down-hooks ]; then
. ${ETCDIR}/dhclient-down-hooks
fi
exit_with_hooks 0
;;
EXPIRE|FAIL|RELEASE|STOP)
execute_client_side_configuration_scripts "restore"
if [ -x ${ETCDIR}/dhclient-${interface}-down-hooks ]; then
. ${ETCDIR}/dhclient-${interface}-down-hooks
elif [ -x ${ETCDIR}/dhclient-down-hooks ]; then
. ${ETCDIR}/dhclient-down-hooks
fi
if [ -n "${alias_ip_address}" ]; then
# Flush alias
ip -4 addr flush dev ${interface} label ${interface}:0 >/dev/null 2>&1
fi
if [ -n "${old_ip_address}" ]; then
# Delete addresses/routes/arp cache.
flush_dev ${interface}
fi
if [ -n "${alias_ip_address}" ]; then
ip -4 addr add ${alias_ip_address}/${alias_prefix} broadcast ${alias_broadcast_address} dev ${interface} label ${interface}:0
ip -4 route replace ${alias_ip_address}/32 dev ${interface}
fi
exit_with_hooks 0
;;
TIMEOUT)
if [ -n "${new_routers}" ]; then
if [ -n "${alias_ip_address}" ]; then
ip -4 addr flush dev ${interface} label ${interface}:0 >/dev/null 2>&1
fi
ip -4 addr add ${new_ip_address}/${new_prefix} \
broadcast ${new_broadcast_address} dev ${interface} \
valid_lft ${new_dhcp_lease_time} preferred_lft ${new_dhcp_lease_time}
set ${new_routers}
if ping -q -c 1 -w 10 -I ${interface} ${1}; then
dhconfig
exit_with_hooks 0
fi
flush_dev ${interface}
exit_with_hooks 1
else
exit_with_hooks 1
fi
;;
*)
logmessage "unhandled state: ${reason}"
exit_with_hooks 1
;;
esac
exit_with_hooks 0