#!/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>

device=$1
if [ "$device" = "" ]; then
	echo "usage: $0 <net-device>"
	exit 1
fi

parent_device=$device

. network-functions

       #
       # Grab the current configuration of any running aliases device info is placed into 
       # variables in the form: rdev_$DEVICE_addr, dev_$DEVICE_mb and rdevip_$IPGLOP.
       # A list of all the devices is created in rdev_LIST.
       #

# sorry this is all one line -- it didn't work on multiple lines for me
eval ` ifconfig | sed -e ' /^[^[:space:]]*:[0-9]*/ { s|^\([^:]*\):\([0-9]*\).*$|X=x; TMP="\2"; [ "$device" != "\1" ] \|\| |g; b; }; /^[^[:space:]]/ { s|.*|X=x; [ 0 = 0 ] \|\| |g; b; }; /inet addr:[0-9]*\.[0-9]*\.[0-9]*\.[0-9]* *Bcast:[0-9.]* *Mask:[0-9.]*/ { s|^.*inet addr:\(\([0-9]*\)\.\([0-9]*\)\.\([0-9]*\)\.\([0-9]*\)\) *Bcast:\([0-9.]*\) *Mask:\([0-9.]*\).*$|eval " rdev_${TMP}_addr=\1; rdev_${TMP}_mb=\7_\6; rdevip_\2_\3_\4_\5=${TMP}; rdev_LIST=\\\\"\\\\$rdev_LIST \\\\${TMP}\\\\"; " \|\| |g; b; }; s|^.*$||g; ' ` X=x;

if [ -z "$rdev_LIST" ]; then
       no_devices_are_up=yes
fi

##for DEVNUM in $rdev_LIST ; do
##eval "
##echo \"rdev_${DEVNUM}_addr = \$rdev_${DEVNUM}_addr\"
##echo \"rdev_${DEVNUM}_mb = \$rdev_${DEVNUM}_mb\" ";
##done
##echo ""; echo "-----"; echo ""

       #
       # 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
PARENTCONFIG=ifcfg-$device
[ -f $PARENTCONFIG ] || {
       echo "Missing config file $PARENTCONFIG." >&2
       exit 1
}
eval ` (
       . $PARENTCONFIG;
       echo default_NETMASK=$NETMASK\;;
       echo default_BROADCAST=$BROADCAST\;;
       echo default_GATEWAY=$GATEWAY\;;
       echo default_GATEWAYDEV=$GATEWAYDEV\;;
       echo default_NO_ALIASROUTING=$NO_ALIASROUTING\;;
) `

function ini_env ()
{
       DEVICE=""
       IPADDR=""
       NETMASK=$default_NETMASK
       BROADCAST=$default_BROADCAST
       GATEWAY=$default_GATEWAY
       GATEWAYDEV=$default_GATEWAYDEV
       NO_ALIASROUTING=$default_NO_ALIASROUTING
}

       #
       # Read the alias configuation 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#*:}

       eval "
              ipseen=\$ipseen_${IPGLOP}; devseen=\$devseen_${DEVNUM};
              ipseen_${IPGLOP}=$FILE; devseen_${DEVNUM}=$FILE;
       ";

       if [ -n "$ipseen" ]; then
              echo "error in $FILE: already seen ipaddr $IPADDR in $ipseen" >&2;exit 0
       fi

       if [ -n "$devseen" ]; then
              echo "error in $FILE: already seen device $parent_device:$DEVNUM\ in $devseen" >&2; exit 0
       fi
       
       if [ -z "$DEVICE" -o -z "$IPADDR" ]; then
              echo "error in $FILE: didn't specify device or ipaddr" >&2 ; exit 0
       fi

       if [ -z "$NETMASK" ]; then
               eval `/bin/ipcalc --netmask ${IPADDR}`
       fi

       if [ -z "$BROADCAST" ]; then
               eval `/bin/ipcalc --broadcast ${IPADDR} ${NETMASK}`
               nma=$NETMASK; nmb=${nma#*.}; nmc=${nmb#*.};
               NMGLOP="${nma%%.*}_${nmb%%.*}_${nmc%%.*}_${nmc#*.}";
               if [ ${nma%%.*} -eq 0 ]; then ipnm_a=0; else ipnm_a=${ipa%%.*}; fi
               if [ ${nmb%%.*} -eq 0 ]; then ipnm_b=0; else ipnm_b=${ipb%%.*}; fi
               if [ ${nmc%%.*} -eq 0 ]; then ipnm_c=0; else ipnm_c=${ipc%%.*}; fi
               if [ ${nmc#*.}  -eq 0 ]; then ipnm_d=0; else ipnm_d=${ipc#*.};  fi
               CACHENAME="${NMGLOP}_${ipnm_a}_${ipnm_b}_${ipnm_c}_${ipnm_d}"
               eval "
                       if [ -z \"\$bcastcache_${CACHENAME}\" ]; then
                               eval `/bin/ipcalc --broadcast \$IPADDR \$NETMASK`
                               bcastcache_${CACHENAME}=\$BROADCAST
                       else
                               BROADCAST=\$bcastcache_${CACHENAME}
                       fi
               ";
       fi

##echo "";
##echo "----------------------------"
##echo "device = $DEVICE"
##echo "ipaddr = $IPADDR"
##echo "netmask = $NETMASK"
##echo "broadcast = $BROADCAST"
##echo "devnum = $DEVNUM";
##echo "";

       if [ "$no_devices_are_up" = "yes" ]; then
               setup_this=yes
       else

               setup_this=""

               eval "
                       rdev_addr=\$rdev_${DEVNUM}_addr;
                       rdev_mb=\$rdev_${DEVNUM}_mb;
                       rdev_mark=\$rdev_${DEVNUM}_mark;
                       rdevip=\$rdevip_${IPGLOP};
               ";

               if [ -n "$rdev_addr" ]; then
                       if [ "$rdev_addr" = "${IPADDR}" ]; then
                               newmark=keep
                               if [ "$rdev_mb" != "${NETMASK}_${BROADCAST}" ]; then
                                       setup_this=freshen
                               else
                                       setup_this=no
                               fi
                       else
                               if [ "$rdev_mark" != "remove" ]; then
##echo "removing device $parent_device:${DEVNUM} (devnum conflict)"
                                       /sbin/ifconfig $parent_device:${DEVNUM} down
                                       do_netreport=yes
                               fi
                               newmark=remove
                               setup_this=yes
                       fi
                       if [ -n "$rdev_mark" -a "$rdev_mark" != "$newmark" ]; then
                               echo "error in ifcfg-${parent_device}:\* files" >&2 ; exit 0
                       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
                               echo "error in ifcfg-${parent_device}:\* files" >&2 ; exit 0
                       fi
                       if [ "$mark_remove" != "remove" ]; then
                               eval " rdev_${rdevip}_mark=remove ";
##echo "removing device $parent_device:$rdevip (ipaddr conflict)"
                               /sbin/ifconfig $parent_device:$rdevip down
                               do_netreport=yes
                       fi
               fi

       fi

       if [ "$setup_this" = "freshen" ] ; then
               # we can do the freshen stuff right now
##echo "freshening device $DEVICE"
               /sbin/ifconfig $DEVICE netmask $NETMASK broadcast $BROADCAST;
       fi

       if [ "$setup_this" = "yes" ] ; then

##echo "setting up device $DEVICE"

               ifconfig ${DEVICE} ${IPADDR} netmask ${NETMASK} broadcast ${BROADCAST}

               if [ "$NO_ALIASROUTING" != yes ]; then

                       route add -host ${IPADDR} ${DEVICE}

                       # this is broken! it's only here for compatibility with old RH systems
                       if [ "${GATEWAY}" != "" -a "${GATEWAY}" != "none" ]; then
                               route add default gw ${GATEWAY} metric 1 ${DEVICE}
                       fi

                       GATEWAY=$network_GATEWAY;
                       GATEWAYDEV=$network_GATEWAYDEV;

                       if [ "${GATEWAY}" != "" ]; then
                               if [ "${GATEWAYDEV}" = "" -o "${GATEWAYDEV}" = "${DEVICE}" ]; then
                                       # set up default gateway
                                       route add default gw ${GATEWAY} ${DEVICE}
                               fi
                       fi

                       if [ -f /etc/sysconfig/static-routes ]; then
                               #note the trailing space in the grep gets rid of aliases
                               grep "^$1 " /etc/sysconfig/static-routes | while read device args; do
                                       /sbin/route add -$args $device
                               done
                       fi

                       do_netreport=yes
                       ifuplocal_queue="$ifuplocal_queue $DEVICE"

               fi

	fi

}

if [ "$BASH_VERSINFO" ]; then shopt -s nullglob; else allow_null_glob_expansion=foo; fi

# This is for linuxconf-style alias files.
aliasnum=0
for FILE in ifcfg-${parent_device}:* ; do

       ini_env;
       . $FILE;
       if [ -z "$DEVICE" ]; then
          # Eek, it's a linuxconf file.
	  
          for address in $IPADDR; do
	       if echo $address | grep -q '-' ; then
	             IPADDR_START=${address%-*}
       		     ipaddr_prefix=${IPADDR_START%.*}
                     ipaddr_startnum=${IPADDR_START##*.}
		     IPADDR_END="${ipaddr_prefix}.${address##*-}"
                     ipaddr_endnum=${IPADDR_END##*.}

                     if [ "${IPADDR_START%.*}" != "${IPADDR_END%.*}" ]; then
                         echo "error in $FILE: IPADDR_START and IPADDR_END don't argree" >&2; exit 0
                     fi

                     if [ $ipaddr_startnum -gt $ipaddr_endnum ]; then
                         echo "error in $FILE: IPADDR_START greater than IPADDR_END" >&2; exit 0
                     fi

                     ipaddr_num=$ipaddr_startnum

                     while [ $ipaddr_num -le $ipaddr_endnum ]; do
                         IPADDR="$ipaddr_prefix.$ipaddr_num"
                         DEVICE="$parent_device:$aliasnum"
                         new_interface;
                         let 'ipaddr_num=ipaddr_num+1'
                         let 'aliasnum=aliasnum+1'
                     done
	       else
	           DEVICE="${parent_device}:${aliasnum}"
		   IPADDR=$address
		   new_interface;
		   let 'aliasnum=aliasnum+1'
	       fi
	  done
       else
         new_interface;
       fi
done

for FILE in ifcfg-${parent_device}-range* ; do

       ini_env;
       . $FILE;

       ipaddr_prefix=${IPADDR_START%.*}
       ipaddr_startnum=${IPADDR_START##*.}
       ipaddr_endnum=${IPADDR_END##*.}

       if [ "${IPADDR_START%.*}" != "${IPADDR_END%.*}" ]; then
               echo "error in $FILE: IPADDR_START and IPADDR_END don't argree" >&2; exit 0
       fi

       if [ $ipaddr_startnum -gt $ipaddr_endnum ]; then
               echo "error in $FILE: IPADDR_START greater than IPADDR_END" >&2; exit 0
       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"
               new_interface;
               let 'ipaddr_num=ipaddr_num+1'
               let '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
##echo "removing device $parent_device:${DEVNUM} (lingering)"
               /sbin/ifconfig $parent_device:${DEVNUM} down
               do_netreport=yes
       fi
done

       #
       # Notify of new device creation
       #

if [ -n "$do_netreport" ]; then
       do_netreport
fi

if [ -x /sbin/ifup-local ]; then
       for DEVICE in $ifuplocal_queue ; do
               /sbin/ifup-local ${DEVICE}
       done
fi