#!/bin/sh

if [ x$new_broadcast_address != x ]; then
  new_broadcast_arg="broadcast $new_broadcast_address"
fi
if [ x$old_broadcast_address != x ]; then
  old_broadcast_arg="broadcast $old_broadcast_address"
fi
if [ x$new_subnet_mask != x ]; then
  new_netmask_arg="netmask $new_subnet_mask"
fi
if [ x$old_subnet_mask != x ]; then
  old_netmask_arg="netmask $old_subnet_mask"
fi
if [ x$alias_subnet_mask != x ]; then
  alias_subnet_arg="netmask $alias_subnet_mask"
fi

if [ x$reason = xMEDIUM ]; then
  ifconfig $interface $medium
  ifconfig $interface inet -alias 0.0.0.0 $medium >/dev/null 2>&1
  ifconfig $interface
  sleep 1
  exit 0
fi

if [ x$reason = xPREINIT ]; then
  if [ x$alias_ip_address != x ]; then
    ifconfig $interface inet -alias $alias_ip_address > /dev/null 2>&1
    route delete $alias_ip_address 127.0.0.1 > /dev/null 2>&1
  fi
  ifconfig $interface inet 0.0.0.0 netmask 0.0.0.0 \
		broadcast 255.255.255.255 up
  exit 0
fi

if [ x$reason = xARPCHECK ] || [ x$reason = xARPSEND ]; then
  exit 0;
fi
  
if [ x$reason = xBOUND ] || [ x$reason = xRENEW ] || \
   [ x$reason = xREBIND ] || [ x$reason = xREBOOT ]; then
  if [ x$old_ip_address != x ] && [ x$alias_ip_address != x ] && \
		[ x$alias_ip_address != x$old_ip_address ]; then
    ifconfig $interface inet -alias $alias_ip_address > /dev/null 2>&1
    route delete $alias_ip_address 127.0.0.1 > /dev/null 2>&1
  fi
  if [ x$old_ip_address != x ] && [ x$old_ip_address != x$new_ip_address ]; then
    ifconfig $interface inet -alias $old_ip_address $medium
    route delete $old_ip_address 127.1 >/dev/null 2>&1
    for router in $old_routers; do
      route delete default $router >/dev/null 2>&1
    done
    arp -n -a | sed -n -e 's/^.*(\(.*\)) at .*$/arp -n -d \1/p' |sh
  fi
  if [ x$old_ip_address = x ] || [ x$old_ip_address != x$new_ip_address ] || \
     [ x$reason = xBOUND ] || [ x$reason = xREBOOT ]; then
    ifconfig $interface inet $new_ip_address $new_netmask_arg \
					$new_broadcast_arg $medium
    route add $new_ip_address 127.1 >/dev/null 2>&1
    for router in $new_routers; do
      route add default $router >/dev/null 2>&1
    done
  fi
  if [ x$new_ip_address != x$alias_ip_address ] && [ x$alias_ip_address != x ];
   then
    ifconfig $interface inet alias $alias_ip_address $alias_subnet_arg
    route add $alias_ip_address 127.0.0.1
  fi
  echo search $new_domain_name >/etc/resolv.conf
  for nameserver in $new_domain_name_servers; do
    echo nameserver $nameserver >>/etc/resolv.conf
  done
  exit 0
fi

if [ x$reason = xEXPIRE ] || [ x$reason = xFAIL ]; then
  if [ x$alias_ip_address != x ]; then
    ifconfig $interface inet -alias $alias_ip_address > /dev/null 2>&1
    route delete $alias_ip_address 127.0.0.1 > /dev/null 2>&1
  fi
  if [ x$old_ip_address != x ]; then
    ifconfig $interface inet -alias $old_ip_address $medium
    route delete $old_ip_address 127.1 >/dev/null 2>&1
    for router in $old_routers; do
      route delete default $router >/dev/null 2>&1
    done
    arp -n -a | sed -n -e 's/^.*(\(.*\)) at .*$/arp -n -d \1/p' \
						|sh >/dev/null 2>&1
  fi
  if [ x$alias_ip_address != x ]; then
    ifconfig $interface inet alias $alias_ip_address $alias_subnet_arg
    route add $alias_ip_address 127.0.0.1
  fi
  exit 0
fi

if [ x$reason = xTIMEOUT ]; then
  if [ x$alias_ip_address != x ]; then
    ifconfig $interface inet -alias $alias_ip_address > /dev/null 2>&1
    route delete $alias_ip_address 127.0.0.1 > /dev/null 2>&1
  fi
  ifconfig $interface inet $new_ip_address $new_netmask_arg \
					$new_broadcast_arg $medium
  sleep 1
  set $new_routers
  if ping -q -c 1 -w 1 $1; then
    if [ x$new_ip_address != x$alias_ip_address ] && \
			[ x$alias_ip_address != x ]; then
      ifconfig $interface inet alias $alias_ip_address $alias_subnet_arg
      route add $alias_ip_address 127.0.0.1
    fi
    route add $new_ip_address 127.1 >/dev/null 2>&1
    for router in $new_routers; do
      route add default $router >/dev/null 2>&1
    done
    echo search $new_domain_name >/etc/resolv.conf.std
    for nameserver in $new_domain_name_servers; do
      echo nameserver $nameserver >>/etc/resolv.conf.std
    done
    if [ -f /etc/resolv.conf ]; then
      rm -f /etc/resolv.conf
      ln /etc/resolv.conf.std /etc/resolv.conf
    fi
    exit 0
  fi
  ifconfig $interface inet -alias $new_ip_address $medium
  for router in $old_routers; do
    route delete default $router >/dev/null 2>&1
  done
  arp -n -a | sed -n -e 's/^.*(\(.*\)) at .*$/arp -n -d \1/p' \
							|sh >/dev/null 2>&1
  exit 1
fi

exit 0