sbin/dhclient/dhclient-script

   1 #!/bin/sh
   2 #
   3 # $OpenBSD: dhclient-script,v 1.6 2004/05/06 18:22:41 claudio Exp $
   4 # $FreeBSD$
   5 #
   6 # Copyright (c) 2003 Kenneth R Westerback <krw@openbsd.org>
   7 #
   8 # Permission to use, copy, modify, and distribute this software for any
   9 # purpose with or without fee is hereby granted, provided that the above
  10 # copyright notice and this permission notice appear in all copies.
  11 #
  12 # THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  13 # WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  14 # MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  15 # ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  16 # WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  17 # ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  18 # OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  19 #
  20 #
  21
  22 NETSTAT=/usr/bin/netstat
  23 GREP=/usr/bin/grep
  24 AWK=/usr/bin/awk
  25 HOSTNAME=/bin/hostname
  26
  27 LOCALHOST=127.0.0.1
  28
  29 if [ -x /usr/bin/logger ]; then
  30         LOGGER="/usr/bin/logger -s -p user.notice -t dhclient"
  31 else
  32         LOGGER=echo
  33 fi
  34
  35 #
  36 # Helper functions that implement common actions.
  37 #
  38
  39 check_hostname() {
  40         current_hostname=`$HOSTNAME`
  41         if [ -z "$current_hostname" ]; then
  42                 $LOGGER "New Hostname ($interface): $new_host_name"
  43                 $HOSTNAME $new_host_name
  44         elif [ "$current_hostname" = "$old_host_name" -a \
  45                "$new_host_name" != "$old_host_name" ]; then
  46                 $LOGGER "New Hostname ($interface): $new_host_name"
  47                 $HOSTNAME $new_host_name
  48         fi
  49 }
  50
  51 arp_flush() {
  52         arp -an -i $interface | \
  53                 sed -n -e 's/^.*(\(.*\)) at .*$/arp -d \1/p' | \
  54                 sh >/dev/null 2>&1
  55 }
  56
  57 delete_old_address() {
  58         ifconfig $interface inet -alias $old_ip_address $medium
  59 }
  60
  61 add_new_address() {
  62         ifconfig $interface \
  63                 inet $new_ip_address \
  64                 netmask $new_subnet_mask \
  65                 broadcast $new_broadcast_address \
  66                 $medium
  67
  68         $LOGGER "New IP Address ($interface): $new_ip_address"
  69         $LOGGER "New Subnet Mask ($interface): $new_subnet_mask"
  70         $LOGGER "New Broadcast Address ($interface): $new_broadcast_address"
  71         $LOGGER "New Routers ($interface): $new_routers"
  72 }
  73
  74 delete_old_alias() {
  75         if [ -n "$alias_ip_address" ]; then
  76                 ifconfig $interface inet -alias $alias_ip_address > /dev/null 2>&1
  77                 route delete $alias_ip_address $LOCALHOST > /dev/null 2>&1
  78         fi
  79 }
  80
  81 add_new_alias() {
  82         if [ -n "$alias_ip_address" ]; then
  83                 ifconfig $interface inet alias $alias_ip_address netmask \
  84                     $alias_subnet_mask
  85                 route add $alias_ip_address $LOCALHOST
  86         fi
  87 }
  88
  89 delete_old_routes() {
  90         route delete "$old_ip_address" $LOCALHOST >/dev/null 2>&1
  91         for router in $old_routers; do
  92                 if [ $if_defaultroute = x -o $if_defaultroute = $interface ]; then
  93                         route delete default $route >/dev/null 2>&1
  94                 fi
  95         done
  96
  97         if [ -n "$old_static_routes" ]; then
  98                 set $old_static_routes
  99                 while [ $# -gt 1 ]; do
 100                         route delete "$1" "$2"
 101                         shift; shift
 102                 done
 103         fi
 104
 105         arp_flush
 106 }
 107
 108 add_new_routes() {
 109         route add $new_ip_address $LOCALHOST >/dev/null 2>&1
 110         for router in $new_routers; do
 111                 if [ "$new_ip_address" = "$router" ]; then
 112                         route add default -iface $router >/dev/null 2>&1
 113                 else
 114                         route add default $router >/dev/null 2>&1
 115                 fi
 116                 # 2nd and subsequent default routers error out, so explicitly
 117                 # stop processing the list after the first one.
 118                 break
 119         done
 120
 121         if [ -n "$new_static_routes" ]; then
 122                 $LOGGER "New Static Routes ($interface): $new_static_routes"
 123                 set $new_static_routes
 124                 while [ $# -gt 1 ]; do
 125                         route add $1 $2
 126                         shift; shift
 127                 done
 128         fi
 129 }
 130
 131 add_new_resolv_conf() {
 132         # XXX Old code did not create/update resolv.conf unless both
 133         # $new_domain_name and $new_domain_name_servers were provided.  PR
 134         # #3135 reported some ISP's only provide $new_domain_name_servers and
 135         # thus broke the script. This code creates the resolv.conf if either
 136         # are provided.
 137
 138         rm -f /etc/resolv.conf.std
 139
 140         if [ -n "$new_domain_name" ]; then
 141                 echo "search $new_domain_name" >>/etc/resolv.conf.std
 142         fi
 143
 144         if [ -n "$new_domain_name_servers" ]; then
 145                 for nameserver in $new_domain_name_servers; do
 146                         echo "nameserver $nameserver" >>/etc/resolv.conf.std
 147                 done
 148         fi
 149
 150         if [ -f /etc/resolv.conf.std ]; then
 151                 if [ -f /etc/resolv.conf.tail ]; then
 152                         cat /etc/resolv.conf.tail >>/etc/resolv.conf.std
 153                 fi
 154
 155                 # In case (e.g. during OpenBSD installs) /etc/resolv.conf
 156                 # is a symbolic link, take care to preserve the link and write
 157                 # the new data in the correct location.
 158
 159                 if [ -f /etc/resolv.conf ]; then
 160                         cat /etc/resolv.conf > /etc/resolv.conf.save
 161                 fi
 162                 cat /etc/resolv.conf.std > /etc/resolv.conf
 163                 rm -f /etc/resolv.conf.std
 164
 165                 # Try to ensure correct ownership and permissions.
 166                 chown -RL root:wheel /etc/resolv.conf
 167                 chmod -RL 644 /etc/resolv.conf
 168
 169                 return 0
 170         fi
 171
 172         return 1
 173 }
 174
 175 # Must be used on exit.   Invokes the local dhcp client exit hooks, if any.
 176 exit_with_hooks() {
 177         exit_status=$1
 178         if [ -f /etc/dhclient-exit-hooks ]; then
 179                 . /etc/dhclient-exit-hooks
 180         fi
 181         # probably should do something with exit status of the local script
 182         exit $exit_status
 183 }
 184
 185 #
 186 # Start of active code.
 187 #
 188
 189 # Invoke the local dhcp client enter hooks, if they exist.
 190 if [ -f /etc/dhclient-enter-hooks ]; then
 191         exit_status=0
 192         . /etc/dhclient-enter-hooks
 193         # allow the local script to abort processing of this state
 194         # local script must set exit_status variable to nonzero.
 195         if [ $exit_status -ne 0 ]; then
 196                 exit $exit_status
 197         fi
 198 fi
 199
 200 if [ -x $NETSTAT ]; then
 201         if_defaulroute=`$NETSTAT -rn | $GREP "^default" | $AWK '{print $6}'`
 202 else
 203         if_defaultroute="x"
 204 fi
 205
 206 case $reason in
 207 MEDIUM)
 208         ifconfig $interface $medium
 209         ifconfig $interface inet -alias 0.0.0.0 $medium >/dev/null 2>&1
 210         sleep 1
 211         ;;
 212
 213 PREINIT)
 214         delete_old_alias
 215         ifconfig $interface inet 0.0.0.0 netmask 0.0.0.0 broadcast 255.255.255.255 up
 216         ;;
 217
 218 ARPCHECK|ARPSEND)
 219         ;;
 220
 221 BOUND|RENEW|REBIND|REBOOT)
 222         check_hostname
 223         if [ -n "$old_ip_address" ]; then
 224                 if [ "$old_ip_address" != "$alias_ip_address" ]; then
 225                         delete_old_alias
 226                 fi
 227                 if [ "$old_ip_address" != "$new_ip_address" ]; then
 228                         delete_old_address
 229                         delete_old_routes
 230                 fi
 231         fi
 232         if [ "$reason" = BOUND ] || \
 233            [ "$reason" = REBOOT ] || \
 234            [ -z "$old_ip_address" ] || \
 235            [ "$old_ip_address" != "$new_ip_address" ]; then
 236                 add_new_address
 237                 add_new_routes
 238         fi
 239         if [ "$new_ip_address" != "$alias_ip_address" ]; then
 240                 add_new_alias
 241         fi
 242         add_new_resolv_conf
 243         ;;
 244
 245 EXPIRE|FAIL)
 246         delete_old_alias
 247         if [ -n "$old_ip_address" ]; then
 248                 delete_old_address
 249                 delete_old_routes
 250         fi
 251         # XXX Why add alias we just deleted above?
 252         add_new_alias
 253         if [ -f /etc/resolv.conf.save ]; then
 254                 cat /etc/resolv.conf.save > /etc/resolv.conf
 255         fi
 256         ;;
 257
 258 TIMEOUT)
 259         delete_old_alias
 260         add_new_address
 261         sleep 1
 262         if [ -n "$new_routers" ]; then
 263                 $LOGGER "New Routers ($interface): $new_routers"
 264                 set "$new_routers"
 265                 if ping -q -c 1 -w 1 "$1"; then
 266                         if [ "$new_ip_address" != "$alias_ip_address" ]; then
 267                                 add_new_alias
 268                         fi
 269                         add_new_routes
 270                         if add_new_resolv_conf; then
 271                                 exit_with_hooks 0
 272                         fi
 273                 fi
 274         fi
 275         ifconfig $interface inet -alias $new_ip_address $medium
 276         delete_old_routes
 277         exit_with_hooks 1
 278         ;;
 279 esac
 280
 281 exit_with_hooks 0