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 ARP=/usr/sbin/arp
  23 AWK=/usr/bin/awk
  24 HOSTNAME=/bin/hostname
  25 NETSTAT=/usr/bin/netstat
  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         eval "ifconfig $interface inet -alias $old_ip_address $medium"
  59 }
  60
  61 add_new_address() {
  62         eval "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 $new_domain_name_servers and
 135         # thus broke the script. This code creates the resolv.conf if either
 136         # are provided.
 137
 138         local tmpres=/var/run/resolv.conf.${interface}
 139         rm -f $tmpres
 140
 141         if [ -n "$new_domain_name" ]; then
 142                 echo "search $new_domain_name" >>$tmpres
 143         fi
 144
 145         if [ -n "$new_domain_name_servers" ]; then
 146                 for nameserver in $new_domain_name_servers; do
 147                         echo "nameserver $nameserver" >>$tmpres
 148                 done
 149         fi
 150
 151         if [ -f $tmpres ]; then
 152                 if [ -f /etc/resolv.conf.tail ]; then
 153                         cat /etc/resolv.conf.tail >>$tmpres
 154                 fi
 155
 156                 # When resolv.conf is not changed actually, we don't
 157                 # need to update it.
 158                 # If /usr is not mounted yet, we cannot use cmp, then
 159                 # the following test fails.  In such case, we simply
 160                 # ignore an error and do update resolv.conf.
 161                 if cmp -s $tmpres /etc/resolv.conf; then
 162                         rm -f $tmpres
 163                         return 0
 164                 fi 2>/dev/null
 165
 166                 # In case (e.g. during OpenBSD installs) /etc/resolv.conf
 167                 # is a symbolic link, take care to preserve the link and write
 168                 # the new data in the correct location.
 169
 170                 if [ -f /etc/resolv.conf ]; then
 171                         cat /etc/resolv.conf > /etc/resolv.conf.save
 172                 fi
 173                 cat $tmpres > /etc/resolv.conf
 174                 rm -f $tmpres
 175
 176                 # Try to ensure correct ownership and permissions.
 177                 chown -RL root:wheel /etc/resolv.conf
 178                 chmod -RL 644 /etc/resolv.conf
 179
 180                 return 0
 181         fi
 182
 183         return 1
 184 }
 185
 186 # Must be used on exit.   Invokes the local dhcp client exit hooks, if any.
 187 exit_with_hooks() {
 188         exit_status=$1
 189         if [ -f /etc/dhclient-exit-hooks ]; then
 190                 . /etc/dhclient-exit-hooks
 191         fi
 192         # probably should do something with exit status of the local script
 193         exit $exit_status
 194 }
 195
 196 #
 197 # Start of active code.
 198 #
 199
 200 # Invoke the local dhcp client enter hooks, if they exist.
 201 if [ -f /etc/dhclient-enter-hooks ]; then
 202         exit_status=0
 203         . /etc/dhclient-enter-hooks
 204         # allow the local script to abort processing of this state
 205         # local script must set exit_status variable to nonzero.
 206         if [ $exit_status -ne 0 ]; then
 207                 exit $exit_status
 208         fi
 209 fi
 210
 211 if [ -x $NETSTAT ]; then
 212         if_defaultroute=`$NETSTAT -rnf inet | $AWK '{if ($1=="default") printf $6}'`
 213 else
 214         if_defaultroute="x"
 215 fi
 216
 217 case $reason in
 218 MEDIUM)
 219         eval "ifconfig $interface $medium"
 220         eval "ifconfig $interface inet -alias 0.0.0.0 $medium" >/dev/null 2>&1
 221         sleep 1
 222         ;;
 223
 224 PREINIT)
 225         delete_old_alias
 226         ifconfig $interface inet 0.0.0.0 netmask 0.0.0.0 broadcast 255.255.255.255 up
 227         ;;
 228
 229 ARPCHECK|ARPSEND)
 230         ;;
 231
 232 BOUND|RENEW|REBIND|REBOOT)
 233         check_hostname
 234         if [ -n "$old_ip_address" ]; then
 235                 if [ "$old_ip_address" != "$alias_ip_address" ]; then
 236                         delete_old_alias
 237                 fi
 238                 if [ "$old_ip_address" != "$new_ip_address" ]; then
 239                         delete_old_address
 240                         delete_old_routes
 241                 fi
 242         fi
 243         if [ "$reason" = BOUND ] || \
 244            [ "$reason" = REBOOT ] || \
 245            [ -z "$old_ip_address" ] || \
 246            [ "$old_ip_address" != "$new_ip_address" ]; then
 247                 add_new_address
 248                 add_new_routes
 249         fi
 250         if [ "$new_ip_address" != "$alias_ip_address" ]; then
 251                 add_new_alias
 252         fi
 253         add_new_resolv_conf
 254         ;;
 255
 256 EXPIRE|FAIL)
 257         delete_old_alias
 258         if [ -n "$old_ip_address" ]; then
 259                 delete_old_address
 260                 delete_old_routes
 261         fi
 262         if [ -x $ARP ]; then
 263                 $ARP -d -a -i $interface
 264         fi
 265         # XXX Why add alias we just deleted above?
 266         add_new_alias
 267         if [ -f /etc/resolv.conf.save ]; then
 268                 cat /etc/resolv.conf.save > /etc/resolv.conf
 269         fi
 270         ;;
 271
 272 TIMEOUT)
 273         delete_old_alias
 274         add_new_address
 275         sleep 1
 276         if [ -n "$new_routers" ]; then
 277                 $LOGGER "New Routers ($interface): $new_routers"
 278                 set "$new_routers"
 279                 if ping -q -c 1 -t 1 "$1"; then
 280                         if [ "$new_ip_address" != "$alias_ip_address" ]; then
 281                                 add_new_alias
 282                         fi
 283                         add_new_routes
 284                         if add_new_resolv_conf; then
 285                                 exit_with_hooks 0
 286                         fi
 287                 fi
 288         fi
 289         eval "ifconfig $interface inet -alias $new_ip_address $medium"
 290         delete_old_routes
 291         exit_with_hooks 1
 292         ;;
 293 esac
 294
 295 exit_with_hooks 0