package/dhcp/dhclient-script

   1 #!/bin/sh
   2
   3 # dhclient-script from OpenWRT project
   4 # http://git.openwrt.org/?p=packages.git;a=blob;f=net/isc-dhcp/files/dhclient-script;h=4afebc0ad20ebac51c5baae5ed01c6713e3a0fd0;hb=HEAD
   5
   6 make_resolv_conf() {
   7   if [ x"$new_domain_name_servers" != x ]; then
   8     cat /dev/null > /etc/resolv.conf.dhclient
   9     chmod 644 /etc/resolv.conf.dhclient
  10     if [ x"$new_domain_search" != x ]; then
  11       echo search $new_domain_search >> /etc/resolv.conf.dhclient
  12     elif [ x"$new_domain_name" != x ]; then
  13       # Note that the DHCP 'Domain Name Option' is really just a domain
  14       # name, and that this practice of using the domain name option as
  15       # a search path is both nonstandard and deprecated.
  16       echo search $new_domain_name >> /etc/resolv.conf.dhclient
  17     fi
  18     for nameserver in $new_domain_name_servers; do
  19       echo nameserver $nameserver >>/etc/resolv.conf.dhclient
  20     done
  21
  22   elif [ "x${new_dhcp6_name_servers}" != x ] ; then
  23     cat /dev/null > /etc/resolv.conf.dhclient6
  24     chmod 644 /etc/resolv.conf.dhclient6
  25
  26     if [ "x${new_dhcp6_domain_search}" != x ] ; then
  27       echo search ${new_dhcp6_domain_search} >> /etc/resolv.conf.dhclient6
  28     fi
  29     for nameserver in ${new_dhcp6_name_servers} ; do
  30       echo nameserver ${nameserver} >> /etc/resolv.conf.dhclient6
  31     done
  32   fi
  33
  34   # if both v4 and v6 clients are running, concatenate results
  35   cat /etc/resolv.conf.* > /etc/resolv.conf
  36 }
  37
  38 # Must be used on exit.   Invokes the local dhcp client exit hooks, if any.
  39 exit_with_hooks() {
  40   exit_status=$1
  41   if [ -f /etc/dhclient-exit-hooks ]; then
  42     . /etc/dhclient-exit-hooks
  43   fi
  44 # probably should do something with exit status of the local script
  45   exit $exit_status
  46 }
  47
  48 # Invoke the local dhcp client enter hooks, if they exist.
  49 if [ -f /etc/dhclient-enter-hooks ]; then
  50   exit_status=0
  51   . /etc/dhclient-enter-hooks
  52   # allow the local script to abort processing of this state
  53   # local script must set exit_status variable to nonzero.
  54   if [ $exit_status -ne 0 ]; then
  55     exit $exit_status
  56   fi
  57 fi
  58
  59 ###
  60 ### DHCPv4 Handlers
  61 ###
  62
  63 if [ x$new_broadcast_address != x ]; then
  64   new_broadcast_arg="broadcast $new_broadcast_address"
  65 fi
  66 if [ x$new_subnet_mask != x ]; then
  67   new_subnet_arg="netmask $new_subnet_mask"
  68 fi
  69 if [ x$alias_subnet_mask != x ]; then
  70   alias_subnet_arg="netmask $alias_subnet_mask"
  71 fi
  72
  73 if [ x$reason = xMEDIUM ]; then
  74   # Linux doesn't do mediums (ok, ok, media).
  75   exit_with_hooks 0
  76 fi
  77
  78 if [ x$reason = xPREINIT ]; then
  79   if [ x$alias_ip_address != x ]; then
  80     # Bring down alias interface. Its routes will disappear too.
  81     ifconfig $interface:0- 0.0.0.0
  82   fi
  83   ifconfig $interface 0.0.0.0 up
  84
  85   # We need to give the kernel some time to get the interface up.
  86   sleep 1
  87
  88   exit_with_hooks 0
  89 fi
  90
  91 if [ x$reason = xARPCHECK ] || [ x$reason = xARPSEND ]; then
  92   exit_with_hooks 0
  93 fi
  94
  95 if [ x$reason = xBOUND ] || [ x$reason = xRENEW ] || \
  96    [ x$reason = xREBIND ] || [ x$reason = xREBOOT ]; then
  97   current_hostname=`hostname`
  98   if [ x$current_hostname = x ] || \
  99      [ x$current_hostname = x$old_host_name ]; then
 100     if [ x$current_hostname = x ] || \
 101        [ x$new_host_name != x$old_host_name ]; then
 102       hostname $new_host_name
 103     fi
 104   fi
 105
 106   if [ x$old_ip_address != x ] && [ x$alias_ip_address != x ] && \
 107                 [ x$alias_ip_address != x$old_ip_address ]; then
 108     # Possible new alias. Remove old alias.
 109     ifconfig $interface:0- 0.0.0.0
 110   fi
 111   if [ x$old_ip_address != x ] && [ x$old_ip_address != x$new_ip_address ]; then
 112     # IP address changed. Bringing down the interface will delete all routes,
 113     # and clear the ARP cache.
 114     ifconfig $interface 0.0.0.0 down
 115
 116   fi
 117   if [ x$old_ip_address = x ] || [ x$old_ip_address != x$new_ip_address ] || \
 118      [ x$reason = xBOUND ] || [ x$reason = xREBOOT ]; then
 119
 120     ifconfig $interface $new_ip_address $new_subnet_arg \
 121                                                         $new_broadcast_arg
 122     for router in $new_routers; do
 123       if [ "x$new_subnet_mask" = "x255.255.255.255" ] ; then
 124         route add -host $router dev $interface
 125       fi
 126       route add default gw $router
 127     done
 128   fi
 129   if [ x$new_ip_address != x$alias_ip_address ] && [ x$alias_ip_address != x ];
 130    then
 131     ifconfig $interface:0- 0.0.0.0
 132     ifconfig $interface:0 $alias_ip_address $alias_subnet_arg
 133     route add -host $alias_ip_address $interface:0
 134   fi
 135   make_resolv_conf
 136   exit_with_hooks 0
 137 fi
 138
 139 if [ x$reason = xEXPIRE ] || [ x$reason = xFAIL ] || [ x$reason = xRELEASE ] \
 140    || [ x$reason = xSTOP ]; then
 141   if [ x$alias_ip_address != x ]; then
 142     # Turn off alias interface.
 143     ifconfig $interface:0- 0.0.0.0
 144   fi
 145   if [ x$old_ip_address != x ]; then
 146     # Shut down interface, which will delete routes and clear arp cache.
 147     ifconfig $interface 0.0.0.0 down
 148   fi
 149   if [ x$alias_ip_address != x ]; then
 150     ifconfig $interface:0 $alias_ip_address $alias_subnet_arg
 151     route add -host $alias_ip_address $interface:0
 152   fi
 153
 154   # remove v4 dns configuration for this interface
 155   rm /etc/resolv.conf.dhclient
 156   cat /etc/resolv.conf.* > /etc/resolv.conf
 157
 158   exit_with_hooks 0
 159 fi
 160
 161 if [ x$reason = xTIMEOUT ]; then
 162   if [ x$alias_ip_address != x ]; then
 163     ifconfig $interface:0- 0.0.0.0
 164   fi
 165   ifconfig $interface $new_ip_address $new_subnet_arg \
 166                                         $new_broadcast_arg
 167   set $new_routers
 168   if ping -q -c 1 $1; then
 169     if [ x$new_ip_address != x$alias_ip_address ] && \
 170                         [ x$alias_ip_address != x ]; then
 171       ifconfig $interface:0 $alias_ip_address $alias_subnet_arg
 172       route add -host $alias_ip_address dev $interface:0
 173     fi
 174     for router in $new_routers; do
 175       if [ "x$new_subnet_mask" = "x255.255.255.255" ] ; then
 176         route add -host $router dev $interface
 177       fi
 178       route add default gw $router
 179     done
 180     make_resolv_conf
 181     exit_with_hooks 0
 182   fi
 183   ifconfig $interface 0.0.0.0 down
 184   exit_with_hooks 1
 185 fi
 186
 187 ###
 188 ### DHCPv6 Handlers
 189 ###
 190
 191 if [ x$reason = xPREINIT6 ]; then
 192   # Ensure interface is up.
 193   ifconfig ${interface} up
 194
 195   # Remove any stale addresses from aborted clients.
 196   ip -f inet6 addr flush dev ${interface} scope global
 197
 198   exit_with_hooks 0
 199 fi
 200
 201 if [ x${old_ip6_prefix} != x ] || [ x${new_ip6_prefix} != x ] ; then
 202     echo Prefix ${reason} old=${old_ip6_prefix} new=${new_ip6_prefix}
 203
 204     exit_with_hooks 0
 205 fi
 206
 207 if [ x$reason = xBOUND6 ]; then
 208   if [ x${new_ip6_address} = x ] || [ x${new_ip6_prefixlen} = x ] ; then
 209     exit_with_hooks 2;
 210   fi
 211
 212   ifconfig ${interface} add ${new_ip6_address}/${new_ip6_prefixlen}
 213
 214   # Check for nameserver options.
 215   make_resolv_conf
 216
 217 ### <<
 218   # Set up softwire tunnel
 219   if [ x${new_dhcp6_softwire} != x ] ; then
 220     /etc/init.d/dhclient stop
 221     ifconfig ${interface} 0.0.0.0
 222     ip -6 tunnel add tun0 mode ipip6 \
 223         remote ${new_dhcp6_softwire} \
 224         local ${new_ip6_address} \
 225         dev ${interface} encaplimit none
 226     ip link set tun0 up
 227     ip route add default dev tun0
 228   fi
 229 ### >>
 230
 231   exit_with_hooks 0
 232 fi
 233
 234 if [ x$reason = xRENEW6 ] || [ x$reason = xREBIND6 ]; then
 235   if [ x${new_ip6_address} = x ] || [ x${new_ip6_prefixlen} = x ] ; then
 236     exit_with_hooks 2;
 237   fi
 238
 239   ifconfig ${interface} add ${new_ip6_address}/${new_ip6_prefixlen}
 240
 241   # Make sure nothing has moved around on us.
 242
 243   # Nameservers/domains/etc.
 244   if [ "x${new_dhcp6_name_servers}" != "x${old_dhcp6_name_servers}" ] ||
 245      [ "x${new_dhcp6_domain_search}" != "x${old_dhcp6_domain_search}" ] ; then
 246     make_resolv_conf
 247   fi
 248
 249   exit_with_hooks 0
 250 fi
 251
 252 if [ x$reason = xDEPREF6 ]; then
 253   if [ x${new_ip6_address} = x ] ; then
 254     exit_with_hooks 2;
 255   fi
 256
 257   # Busybox ifconfig has no way to communicate this to the kernel, so ignore it
 258
 259   exit_with_hooks 0
 260 fi
 261
 262 if [ x$reason = xEXPIRE6 -o x$reason = xRELEASE6 -o x$reason = xSTOP6 ]; then
 263   if [ x${old_ip6_address} = x ] || [ x${old_ip6_prefixlen} = x ] ; then
 264     exit_with_hooks 2;
 265   fi
 266
 267   ifconfig ${interface} del ${old_ip6_address}/${old_ip6_prefixlen}
 268
 269   # remove v6 dns configuration for this interface
 270   rm /etc/resolv.conf.dhclient6
 271   cat /etc/resolv.conf.* > /etc/resolv.conf
 272
 273 ### <<
 274   # Tear down softwire tunnel
 275   if [ x${old_dhcp6_softwire} != x ] ; then
 276     ip link set tun0 down
 277     ip tunnel del tun0
 278   fi
 279 ### >>
 280
 281   exit_with_hooks 0
 282 fi
 283
 284 exit_with_hooks 0