#!/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 .
#
# Author(s): David Cantrell
# Jiri Popelka
#
# ----------
# 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 for Fedora and RHEL
# ----------
#
PATH=/bin:/usr/bin:/sbin
# scripts in dhclient.d/ use $SAVEDIR (#833054)
export SAVEDIR=/var/lib/dhclient
LOGFACILITY="local7"
LOGLEVEL="notice"
ETCDIR="/etc/dhcp"
RESOLVCONF="/etc/resolv.conf"
logmessage() {
msg="${1}"
logger -p "${LOGFACILITY}.${LOGLEVEL}" -t "NET" "dhclient: ${msg}"
}
eventually_add_hostnames_domain_to_search() {
# For the case when hostname for this machine has a domain that is not in domain_search list
# 1) get a hostname with `ipcalc --hostname` or `hostnamectl --transient`
# 2) get the domain from this hostname
# 3) add this domain to search line in resolv.conf if it's not already
# there (domain list that we have recently added there is a parameter of this function)
# We can't do this directly when generating resolv.conf in make_resolv_conf(), because
# we need to first save the resolv.conf with obtained values before we can call `ipcalc --hostname`.
# See bug 637763
search="${1}"
if need_hostname; then
status=1
if [ -n "${new_ip_address}" ]; then
eval $(/usr/bin/ipcalc --silent --hostname "${new_ip_address}" ; echo "status=$?")
elif [ -n "${new_ip6_address}" ]; then
eval $(/usr/bin/ipcalc --silent --hostname "${new_ip6_address}" ; echo "status=$?")
fi
if [ ${status} -eq 0 ]; then
domain=$(echo "${HOSTNAME}" | cut -s -d "." -f 2-)
fi
else
domain=$(hostnamectl --transient 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} ${domain}/" "${RESOLVCONF}"
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
if [ -n "${new_domain_name_servers}" ]; then
for nameserver in ${new_domain_name_servers} ; do
echo "nameserver ${nameserver}" >> "${rscf}"
done
else # keep 'old' nameservers
sed -n /^\w*[Nn][Aa][Mm][Ee][Ss][Ee][Rr][Vv][Ee][Rr]/p "${RESOLVCONF}" >> "${rscf}"
fi
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
if [ -n "${new_dhcp6_name_servers}" ]; then
for nameserver in ${new_dhcp6_name_servers} ; do
# If the nameserver has a link-local address
# add a (interface name) to it.
if [[ "$nameserver" =~ ^fe80:: ]]
then
zone_id="%${interface}"
else
zone_id=
fi
echo "nameserver ${nameserver}$zone_id" >> "${rscf}"
done
else # keep 'old' nameservers
sed -n /^\w*[Nn][Aa][Mm][Ee][Ss][Ee][Rr][Vv][Ee][Rr]/p "${RESOLVCONF}" >> "${rscf}"
fi
shopt -u nocasematch
change_resolv_conf "${rscf}"
rm -f "${rscf}"
if [ -n "${search}" ]; then
eventually_add_hostnames_domain_to_search "${search}"
fi
fi
}
# run given script
run_hook() {
local script
local exit_status
script="${1}"
if [ -f ${script} ]; then
. ${script}
fi
if [ -n "${exit_status}" ] && [ "${exit_status}" -ne 0 ]; then
logmessage "${script} returned non-zero exit status ${exit_status}"
fi
return ${exit_status}
}
# run scripts in given directory
run_hookdir() {
local dir
dir="${1}"
if [ -d "${dir}" ]; then
for script in $(run-parts --list $dir); do
run_hook ${script} || return $?
done
fi
return 0
}
exit_with_hooks() {
# Source the documented exit-hook script, if it exists
run_hook "${ETCDIR}/dhclient-exit-hooks" || exit $?
# Now run scripts in the hooks directory.
run_hookdir "${ETCDIR}/dhclient-exit-hooks.d" || exit $?
exit ${1}
}
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
# TODO: This function should not have side effects such as adding or
# removing routes. Can this be done with "ip route get" or similar
# instead? Are there cases that rely on this route being created here?
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
if [ $# -gt 1 ] && [ -n "${2}" ] && [[ "${2}" -gt 0 ]]; then
ip -4 route replace default via "${router}" dev "${interface}" metric "${2}"
else
ip -4 route replace default via "${router}" dev "${interface}"
fi
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}_${1}"
fi
done
fi
}
flush_dev() {
# Instead of bringing the interface down (#574568)
# explicitly clear ARP cache and flush all addresses & routes.
ip -4 addr flush dev "${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
}
remove_old_addr() {
if [ -n "${old_ip_address}" ]; then
if [ -n "${old_prefix}" ]; then
ip -4 addr del "${old_ip_address}/${old_prefix}" dev "${interface}" >/dev/null 2>&1
else
ip -4 addr del "${old_ip_address}" dev "${interface}" >/dev/null 2>&1
fi
fi
}
dhconfig() {
if [ -n "${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
# make sure the interface is up
ip link set dev "${interface}" up
# replace = add if it doesn't exist or override (update lifetimes) if it's there
ip -4 addr replace "${new_ip_address}/${new_prefix}" broadcast "${new_broadcast_address}" dev "${interface}" \
valid_lft "${new_dhcp_lease_time}" preferred_lft "${new_dhcp_lease_time}" >/dev/null 2>&1
if [ "${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}" = "${new_interface_mtu}" ]; then
# The 576 MTU is only used for X.25 and dialup connections
# where the admin wants low latency. Such a low MTU can cause
# problems with UDP traffic, among other things. As such,
# disallow MTUs from 576 and below by default, so that broken
# MTUs are ignored, but higher stuff is allowed (1492, 1500, etc).
if [ -n "${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=(${new_classless_static_routes})
# If the DHCP server returns both a Classless Static Routes option and
# a Router option, the DHCP client MUST ignore the Router option. (RFC3442)
new_routers=""
else
IFS=', |' static_routes=(${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 [ "${target}" = "0" ]; then
new_routers="${static_routes[$i+1]}"
continue
else
prefix=${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 "${interface}"
fi
fi
fi
fi
if [ ! "${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 replace "${alias_ip_address}/${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
hostnamectl set-hostname --transient --no-ask-password "${new_host_name}"
fi
if [[ ( "${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"
}
wait_for_link_local() {
# 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 "${tentative}" ]] && exit_with_hooks 0
sleep 0.1
done
}
# Section 18.1.8. (Receipt of Reply Messages) of RFC 3315 says:
# The client SHOULD perform duplicate address detection on each of
# the addresses in any IAs it receives in the Reply message before
# using that address for traffic.
add_ipv6_addr_with_DAD() {
ip -6 addr replace "${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
[[ -n "${old_ip6_address}" ]] && ip -6 addr del "${old_ip6_address}" dev "${interface}"
fi
# call it even if new_ip6_address = old_ip6_address to update lifetimes
add_ipv6_addr_with_DAD
fi
if [ ! "${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 "${interface}" scope global preferred_lft 0
;;
esac
execute_client_side_configuration_scripts "config"
}
# Functions from /etc/sysconfig/network-scripts/network-functions
need_hostname ()
{
CHECK_HOSTNAME=$(hostnamectl --transient)
if [[ "${CHECK_HOSTNAME}" = "(none)" ]] ||
[[ "${CHECK_HOSTNAME}" = "localhost" ]] ||
[[ "${CHECK_HOSTNAME}" = "localhost.localdomain" ]]; then
return 0
else
return 1
fi
}
# Takes one argument - temporary resolv.conf file
change_resolv_conf ()
{
options=$(grep '^[\ \ ]*option' "${RESOLVCONF}" 2>/dev/null);
if [[ -n "${options}" ]]; then
# merge options from existing resolv.conf with specified resolv.conf content
newres="${options}"$'\n'$(grep -vF "${options}" "${1}");
else
newres=$(cat "${1}");
fi;
eval $(echo "${newres}" > "${RESOLVCONF}"; echo "status=$?")
if [[ $status -eq 0 ]]; then
logger -p local7.notice -t "NET" -i "${0} : updated ${RESOLVCONF}";
[[ -e /var/run/nscd/socket ]] && /usr/sbin/nscd -i hosts; # invalidate cache
fi;
return $status;
}
get_config_by_name ()
{
LANG=C grep -E -i -l \
"^[[:space:]]*NAME=\"(Auto |System )?${1}\"" \
/etc/sysconfig/network-scripts/ifcfg-* \
| LC_ALL=C sed -e "$__sed_discard_ignored_files"
}
get_hwaddr ()
{
if [ -f /sys/class/net/${1}/address ]; then
awk '{ print toupper($0) }' < /sys/class/net/${1}/address
elif [ -d "/sys/class/net/${1}" ]; then
LC_ALL= LANG= ip -o link show ${1} 2>/dev/null | \
awk '{ print toupper(gensub(/.*link\/[^ ]* ([[:alnum:]:]*).*/,
"\\1", 1)); }'
fi
}
validate_resolv_conf()
{
# It's possible to have broken symbolic link $RESOLVCONF ->
# https://bugzilla.redhat.com/1475279
# Remove broken link and hope NM will survive
if [ -h "${RESOLVCONF}" -a ! -e "${RESOLVCONF}" ];
then
logmessage "${RESOLVCONF) is broken symlink. Recreating..."
unlink "${RESOLVCONF}"
touch "${RESOLVCONF}"
fi;
}
get_config_by_hwaddr ()
{
LANG=C grep -il "^[[:space:]]*HWADDR=\"\?${1}\"\?\([[:space:]#]\|$\)" /etc/sysconfig/network-scripts/ifcfg-* \
| LC_ALL=C sed -e "$__sed_discard_ignored_files"
}
get_config_by_device ()
{
LANG=C grep -l "^[[:space:]]*DEVICE=\"\?${1}\"\?\([[:space:]#]\|$\)" \
/etc/sysconfig/network-scripts/ifcfg-* \
| LC_ALL=C sed -e "$__sed_discard_ignored_files"
}
need_config ()
{
# A sed expression to filter out the files that is_ignored_file recognizes
__sed_discard_ignored_files='/\(~\|\.bak\|\.orig\|\.rpmnew\|\.rpmorig\|\.rpmsave\)$/d'
local nconfig
CONFIG="ifcfg-${1}"
[ -f "${CONFIG}" ] && return
CONFIG="${1##*/}"
[ -f "${CONFIG}" ] && return
nconfig=$(get_config_by_name "${1}")
if [ -n "$nconfig" ] && [ -f "$nconfig" ]; then
CONFIG=${nconfig##*/}
return
fi
local addr=$(get_hwaddr ${1})
if [ -n "$addr" ]; then
nconfig=$(get_config_by_hwaddr ${addr})
if [ -n "$nconfig" ] ; then
CONFIG=${nconfig##*/}
[ -f "${CONFIG}" ] && return
fi
fi
nconfig=$(get_config_by_device ${1})
if [ -n "$nconfig" ] && [ -f "$nconfig" ]; then
CONFIG=${nconfig##*/}
return
fi
}
# We need this because of PEERDNS
source_config ()
{
CONFIG=${CONFIG##*/}
. /etc/sysconfig/network-scripts/$CONFIG
}
#
# ### MAIN
#
# Invoke the local dhcp client enter hooks, if they exist.
run_hook "${ETCDIR}/dhclient-enter-hooks" || exit $?
run_hookdir "${ETCDIR}/dhclient-enter-hooks.d" || exit $?
[ "${PEERDNS}" = "no" ] || validate_resilv_conf()
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
# In case there's some delay in rebinding, it might happen, that the valid_lft drops to 0,
# address is removed by kernel and then re-added few seconds later by dhclient-script.
# With this work-around the address lives a minute longer.
# "4294967235" = infinite (forever) - 60
[[ "${new_dhcp_lease_time}" -lt "4294967235" ]] && new_dhcp_lease_time=$((new_dhcp_lease_time + 60))
[[ "${new_max_life}" -lt "4294967235" ]] && new_max_life=$((new_max_life + 60))
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
# Removing stale addresses from aborted clients shouldn't be needed
# since we've been adding addresses with lifetimes.
# Which means that kernel eventually removes them automatically.
# ip -6 addr flush dev "${interface}" scope global permanent
wait_for_link_local
exit_with_hooks 0
;;
BOUND|RENEW|REBIND|REBOOT)
if [ -z "${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}" = *"${ARP_REPLY}"* ]]; then
# the reply can come from our system, that's OK (#1116004#c33)
dhconfig
exit_with_hooks 0
else
exit_with_hooks 1
fi
fi
;;
BOUND6|RENEW6|REBIND6|DEPREF6)
dh6config
exit_with_hooks 0
;;
EXPIRE6|RELEASE6|STOP6)
if [ -z "${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
# upstream script sets interface down here,
# we only remove old ip address
#flush_dev ${interface}
remove_old_addr
if [ -n "${alias_ip_address}" ]; then
ip -4 addr replace "${alias_ip_address}/${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 "${interface}:0" >/dev/null 2>&1
fi
ip -4 addr replace "${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}
remove_old_addr
exit_with_hooks 1
else
exit_with_hooks 1
fi
;;
*)
logmessage "unhandled state: ${reason}"
exit_with_hooks 1
;;
esac
exit_with_hooks 0