#!/bin/bash
#
# configures aliases of device $1
#
# This script goes out of its way to arrive at the configuration of ip
# aliases described in the ifcfg-$DEV:* and ifcfg-$DEV-range* files from
# whatever existing configuration it may be given: existing aliases not
# specified in the configuration will be removed, netmasks and broadcast
# addrs will be updated on existing aliases, and new aliases will be setup.
#
# range specification files:
#
# One can specify ranges of alised ipaddress using ifcfg-$DEV-range* files.
# Specify multiple ranges using multiple files, such as ifcfg-eth0-range0 and
# ifcfg-eth0-range1, etc. In these files, the following configuration variables
# specify the range:
#
# IPADDR_START -- ipaddr to start range at. eg "192.168.30.1"
# IPADDR_END -- ipaddr to end range at. eg "192.168.30.254"
# CLONENUM_START -- interface clone number to start using for this range. eg "0"
#
# The above example values create the interfaces eth0:0 through eth0:253 using
# ipaddrs 192.168.30.1 through 192.168.30.254, inclusive.
#
# Other configuration variables such as NETMASK and BROADCAST may be specified
# in the range file and will apply to all of the ipaddresses in the range. Range
# files also inherit configuration from the ifcfg-$DEV file just like normal.
#
# Note that IPADDR_START and IPADR_END are required to be in the same class-c
# block. I.e. IPADDR_START=192.168.30.1 and IPADDR_END=192.168.31.255 is
# not valid.
#
# speed with large sets of interfaces:
#
# Considerable effort was spent making this script fast. It can efficiently
# handle a thousand ip aliases on one interface.
#
# With large sets of ipaddresses the NO_ALIASROUTING=yes configuration is
# highly recommended. (This can be specified in ifcfg-$DEV and inherited.) This
# prevents this script from setting up routing details for the virtual
# interfaces, which I don't think is needed, because outgoing traffic can use the
# main interface. However, make your own conclusions on what you need.
#
# My test setup of four class C address blocks on a P166 took 25 seconds of
# which 16 seconds of this was spent in the ifcconfig calls. Without the
# NO_ALIASROUTING=yes config an additional 12 seconds is spent in route calls.
#
# notes on internals:
#
# This script uses the bash "eval" command to lookup shell variables with names
# which are generated from other shell variables. This allows us to, in effect,
# create hashes using the shell variable namesspace by just including the hash
# key in the name of the variable.
#
# This script originally written by: David Harris <dharris@drh.net>
# Principal Engineer, DRH Internet
# June 30, 1999
#
# modified by: Bill Nottingham <notting@redhat.com>
TEXTDOMAIN=initscripts
TEXTDOMAINDIR=/etc/locale
device=$1
if [ "$device" = "" ]; then
echo $"usage: ifup-aliases <net-device> [<parent-config>]\n"
exit 1
fi
PARENTCONFIG=${2:-ifcfg-$device}
parent_device=$device
cd /etc/sysconfig/network-scripts
. ./network-functions
# Grab the current configuration of any running aliases, place device info
# into variables of the form:
# rdev_<index>_addr = <ip address>
# rdev_<index>_pb = <prefix>_<broadcast>
# rdevip_<ipaddress> = <index>
# Example:
# rdev_0_addr=192.168.1.1
# rdev_0_pb=24_192.16.1.255
# rdevip_192_168_1_1=0
#
# A list of all the devices is created in rdev_LIST.
eval $( ip addr show $device label $device:* | \
awk 'BEGIN { COUNT=0;LAST_DEV="" } /inet / {
# Split IP address into address/prefix
split($2,IPADDR,"/");
# Create A_B_C_D IP address form
IP_ADDR=IPADDR[1];
gsub(/\./,"_",IP_ADDR);
# Split device into device:index
split($NF,DEV,":");
# Update last device
LAST_DEV=LAST_DEV " " DEV[2];
printf("rdev_%s_addr=%s\nrdevip_%s=%s\nrdev_%s_pb=%s_%s\nrdev_LIST=\"%s\"\n",
DEV[2],IPADDR[1],IP_ADDR,DEV[2],DEV[2],IPADDR[2],$4,LAST_DEV);
} END {
if(LAST_DEV == "") print "no_devices_are_up=yes"
}' );
#
# Store configuration of the parent device and network
#
# read from the /etc/sysconfig/network
eval ` (
. /etc/sysconfig/network;
echo network_GATEWAY=$GATEWAY\;;
echo network_GATEWAYDEV=$GATEWAYDEV\;;
) `
# read defaults from the parent config file
[ -f $PARENTCONFIG ] || {
net_log $"Missing config file $PARENTCONFIG."
exit 1
}
eval ` (
. ./$PARENTCONFIG;
echo default_PREFIX=$PREFIX\;;
echo default_NETMASK=$NETMASK\;;
echo default_BROADCAST=$BROADCAST\;;
echo default_GATEWAY=$GATEWAY\;;
echo default_NO_ALIASROUTING=$NO_ALIASROUTING\;;
echo default_ARPCHECK=$ARPCHECK\;;
echo default_ARPUPDATE=$ARPUPDATE\;;
) `
[ -z "$default_GATEWAY" ] && default_GATEWAY=$network_GATEWAY
function ini_env ()
{
DEVICE=""
IPADDR=""
IPV6ADDR=""
PREFIX=$default_PREFIX
NETMASK=$default_NETMASK
BROADCAST=$default_BROADCAST
GATEWAY=$default_GATEWAY
NO_ALIASROUTING=$default_NO_ALIASROUTING
ONPARENT=""
ARPCHECK=$default_ARPCHECK
ARPUPDATE=$default_ARPUPDATE
}
function is_default_gateway ()
{
LC_ALL=C /sbin/ip route ls default scope global \
| awk '$3 == "'"$1"'" { found = 1; } END { exit found == 0; }'
}
#
# Read the alias configuration files and enable each aliased
# device using new_interface()
#
function new_interface ()
{
ipa=$IPADDR; ipb=${ipa#*.}; ipc=${ipb#*.};
IPGLOP="${ipa%%.*}_${ipb%%.*}_${ipc%%.*}_${ipc#*.}";
DEVNUM=${DEVICE#*:}
MATCH='^[0-9A-Za-z_]*$'
if (LC_ALL=C; [[ ! "$DEVNUM" =~ $MATCH ]]); then
net_log $"error in $FILE: invalid alias number"
return 1
fi
eval "
ipseen=\$ipseen_${IPGLOP}; devseen=\$devseen_${DEVNUM};
ipseen_${IPGLOP}=$FILE; devseen_${DEVNUM}=$FILE;
";
if [ -n "$ipseen" ]; then
net_log $"error in $FILE: already seen ipaddr $IPADDR in $ipseen"
return 1
fi
if [ -n "$devseen" ]; then
net_log $"error in $FILE: already seen device $parent_device:$DEVNUM in $devseen"
return 1
fi
if [ -z "$DEVICE" -o -z "$IPADDR" ]; then
if [ -n "$IPV6ADDR" -a -n "$DEVICE" ] && ! is_false "$IPV6INIT"; then
/etc/sysconfig/network-scripts/ifup-ipv6 ${DEVICE}
return $?
fi
net_log $"error in $FILE: didn't specify device or ipaddr"
return 1
fi
if [ -z "$NETMASK" -a -z "$PREFIX" ]; then
net_log $"error iN $FILE: didn't specify netmask or prefix"
fi
if [ -z "$PREFIX" ]; then
eval $(/bin/ipcalc --prefix ${IPADDR} ${NETMASK})
fi
if [ -z "$BROADCAST" -o "$BROADCAST" = "$default_BROADCAST" ]; then
eval $(/bin/ipcalc --broadcast ${IPADDR}/${PREFIX})
fi
if [ "$no_devices_are_up" = "yes" ]; then
setup_this=yes
else
setup_this=""
eval "
rdev_addr=\$rdev_${DEVNUM}_addr;
rdev_pb=\$rdev_${DEVNUM}_pb;
rdev_mark=\$rdev_${DEVNUM}_mark;
rdevip=\$rdevip_${IPGLOP};
";
if [ -n "$rdev_addr" ]; then
if [ "$rdev_addr" = "${IPADDR}" ]; then
newmark=keep
if [ "$rdev_pb" != "${PREFIX}_${BROADCAST}" ]; then
setup_this=freshen
else
setup_this=no
fi
else
if [ "$rdev_mark" != "remove" ]; then
/sbin/ip addr flush dev $parent_device label $parent_device:${DEVNUM}
fi
newmark=remove
setup_this=yes
fi
if [ -n "$rdev_mark" -a "$rdev_mark" != "$newmark" ]; then
net_log $"error in ifcfg-${parent_device}: files"
return 1
fi
eval " rdev_${DEVNUM}_mark=\$newmark ";
else
setup_this=yes
fi
if [ -n "$rdevip" -a "$rdevip" != "${DEVNUM}" ]; then
eval " mark_remove=\$rdev_${rdevip}_mark ";
if [ -n "$mark_remove" -a "$mark_remove" != "remove" ]; then
net_log $"error in ifcfg-${parent_device}: files"
return 1
fi
if [ "$mark_remove" != "remove" ]; then
eval " rdev_${rdevip}_mark=remove ";
/sbin/ip addr flush dev $parent_device label $parent_device:$rdevip
fi
fi
fi
if [ "$setup_this" = "freshen" ] ; then
# we can do the freshen stuff right now
/sbin/ip addr change ${IPADDR}/${PREFIX} brd ${BROADCAST}
fi
if [ "$setup_this" = "yes" ] ; then
if [ "${parent_device}" != "lo" ] && [ "${ARPCHECK}" != "no" ] && \
is_available ${parent_device} && \
( grep -qswi "up" /sys/class/net/${parent_device}/operstate || grep -qswi "1" /sys/class/net/${parent_device}/carrier ) ; then
echo $"Determining if ip address ${IPADDR} is already in use for device ${parent_device}..."
ARPING=$(/sbin/arping -c 2 -w ${ARPING_WAIT:-3} -D -I ${parent_device} ${IPADDR})
if [ $? = 1 ]; then
ARPINGMAC=$(echo $ARPING | sed -ne 's/.*\[\(.*\)\].*/\1/p')
net_log $"Error, some other host ($ARPINGMAC) already uses address ${IPADDR}."
return 1
fi
fi
/sbin/ip addr add ${IPADDR}/${PREFIX} brd ${BROADCAST} \
dev ${parent_device} label ${DEVICE}
# update ARP cache of neighboring computers:
if ! is_false "${ARPUPDATE}" && [ "${REALDEVICE}" != "lo" ]; then
/sbin/arping -q -A -c 1 -I ${parent_device} ${IPADDR}
( sleep 2; /sbin/arping -q -U -c 1 -I ${parent_device} ${IPADDR} ) > /dev/null 2>&1 < /dev/null &
fi
! is_false "$IPV6INIT" && \
/etc/sysconfig/network-scripts/ifup-ipv6 ${DEVICE}
if [ "$NO_ALIASROUTING" != yes ]; then
GATEWAYDEV=$network_GATEWAYDEV;
if [ -n "${GATEWAY}" -a \
\( -z "${GATEWAYDEV}" -o "${GATEWAYDEV}" = "${DEVICE}" \) ]; then
# set up default gateway, if it isn't already there
if ! is_default_gateway "$GATEWAY"; then
ip route replace default ${METRIC:+metric $METRIC} via ${GATEWAY} dev ${DEVICE}
fi
fi
/etc/sysconfig/network-scripts/ifup-routes ${DEVICE} ${NAME}
ifuplocal_queue="$ifuplocal_queue $DEVICE"
fi
fi
}
if [ "$BASH_VERSINFO" ]; then
shopt -s nullglob
else
allow_null_glob_expansion=foo
fi
for FILE in ifcfg-${parent_device}:* ; do
is_ignored_file "$FILE" && continue
ini_env
. ./$FILE
[ -z "$DEVICE" ] && DEVICE=${FILE##ifcfg-}
[ "$ONPARENT" != "no" -a "$ONPARENT" != "NO" ] && new_interface
unset DEVICE
done
for FILE in ifcfg-${parent_device}-range* ; do
is_ignored_file "$FILE" && continue
ini_env
. ./$FILE
ipaddr_prefix=${IPADDR_START%.*}
ipaddr_startnum=${IPADDR_START##*.}
ipaddr_endnum=${IPADDR_END##*.}
if [ "${IPADDR_START%.*}" != "${IPADDR_END%.*}" ]; then
net_log $"error in $FILE: IPADDR_START and IPADDR_END don't agree"
continue
fi
if [ $ipaddr_startnum -gt $ipaddr_endnum ]; then
net_log $"error in $FILE: IPADDR_START greater than IPADDR_END"
continue
fi
ipaddr_num=$ipaddr_startnum
ipaddr_clonenum=$CLONENUM_START
while [ $ipaddr_num -le $ipaddr_endnum ]; do
IPADDR="$ipaddr_prefix.$ipaddr_num"
DEVICE="$parent_device:$ipaddr_clonenum"
IPV6INIT="no"
[ "$ONPARENT" != "no" -a "$ONPARENT" != "NO" ] && new_interface
ipaddr_num=$(($ipaddr_num+1))
ipaddr_clonenum=$(($ipaddr_clonenum+1))
done
done
#
# Remove any devices that should not be around
#
for DEVNUM in $rdev_LIST ; do
eval " rdev_mark=\$rdev_${DEVNUM}_mark "
if [ -z "$rdev_mark" ]; then
/sbin/ip addr flush dev $parent_device label $parent_device:${DEVNUM}
fi
done
if [ -x /sbin/ifup-local ]; then
for DEVICE in $ifuplocal_queue ; do
/sbin/ifup-local ${DEVICE}
done
fi