--- /dev/null
+#!/bin/bash
+# dhclient-script for Linux. Dan Halbert, March, 1997.
+# Updated for Linux 2.[12] by Brian J. Murrell, January 1999.
+# No guarantees about this. I'm a novice at the details of Linux
+# networking.
+
+# Notes:
+
+# 0. This script is based on the netbsd script supplied with dhcp-970306.
+
+# 1. ifconfig down apparently deletes all relevant routes and flushes
+# the arp cache, so this doesn't need to be done explicitly.
+
+# 2. The alias address handling here has not been tested AT ALL.
+# I'm just going by the doc of modern Linux ip aliasing, which uses
+# notations like eth0:0, eth0:1, for each alias.
+
+# 3. I have to calculate the network address, and calculate the broadcast
+# address if it is not supplied. This might be much more easily done
+# by the dhclient C code, and passed on.
+
+# 4. TIMEOUT not tested. ping has a flag I don't know, and I'm suspicious
+# of the $1 in its args.
+
+if [ -n "${dhc_dbus}" ]; then
+ if [ -x /usr/bin/dbus-send ]; then
+ /usr/bin/dbus-send \
+ --system \
+ --dest=com.redhat.dhcp \
+ --type=method_call \
+ /com/redhat/dhcp/$interface \
+ com.redhat.dhcp.set \
+ 'string:'"`env | /bin/egrep -v '^(PATH|SHLVL|_|PWD|dhc_dbus)\='`";
+
+ if (( ( dhc_dbus & 31 ) == 31 )); then
+ exit 0;
+ fi;
+ fi;
+fi;
+
+make_resolv_conf() {
+ if [ x"$new_domain_name_servers" != x ]; then
+ cat /dev/null > /etc/resolv.conf.dhclient
+ chmod 644 /etc/resolv.conf.dhclient
+ if [ x"$new_domain_search" != x ]; then
+ echo search $new_domain_search >> /etc/resolv.conf.dhclient
+ elif [ x"$new_domain_name" != x ]; then
+ # Note that the DHCP 'Domain Name Option' is really just a domain
+ # name, and that this practice of using the domain name option as
+ # a search path is both nonstandard and deprecated.
+ echo search $new_domain_name >> /etc/resolv.conf.dhclient
+ fi
+ for nameserver in $new_domain_name_servers; do
+ echo nameserver $nameserver >>/etc/resolv.conf.dhclient
+ done
+
+ mv /etc/resolv.conf.dhclient /etc/resolv.conf
+ fi
+}
+
+# Must be used on exit. Invokes the local dhcp client exit hooks, if any.
+exit_with_hooks() {
+ exit_status=$1
+ if [ -f /etc/dhclient-exit-hooks ]; then
+ . /etc/dhclient-exit-hooks
+ fi
+# probably should do something with exit status of the local script
+ exit $exit_status
+}
+
+# Invoke the local dhcp client enter hooks, if they exist.
+if [ -f /etc/dhclient-enter-hooks ]; then
+ exit_status=0
+ . /etc/dhclient-enter-hooks
+ # allow the local script to abort processing of this state
+ # local script must set exit_status variable to nonzero.
+ if [ $exit_status -ne 0 ]; then
+ exit $exit_status
+ fi
+fi
+
+release=`uname -r`
+release=`expr $release : '\(.*\)\..*'`
+relminor=`echo $release |sed -e 's/[0-9]*\.\([0-9][0-9]*\)\(\..*\)*$/\1/'`
+relmajor=`echo $release |sed -e 's/\([0-9][0-9]*\)\..*$/\1/'`
+
+if [ x$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_subnet_arg="netmask $new_subnet_mask"
+fi
+if [ x$old_subnet_mask != x ]; then
+ old_subnet_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
+ # Linux doesn't do mediums (ok, ok, media).
+ exit_with_hooks 0
+fi
+
+if [ x$reason = xPREINIT ]; then
+ if [ x$alias_ip_address != x ]; then
+ # Bring down alias interface. Its routes will disappear too.
+ ifconfig $interface:0- inet 0
+ fi
+ if [ $relmajor -lt 2 ] || ( [ $relmajor -eq 2 ] && [ $relminor -eq 0 ] )
+ then
+ ifconfig $interface inet 0.0.0.0 netmask 0.0.0.0 \
+ broadcast 255.255.255.255 up
+ # Add route to make broadcast work. Do not omit netmask.
+ route add default dev $interface netmask 0.0.0.0
+ else
+ ifconfig $interface 0 up
+ fi
+
+ # We need to give the kernel some time to get the interface up.
+ sleep 1
+
+ exit_with_hooks 0
+fi
+
+if [ x$reason = xARPCHECK ] || [ x$reason = xARPSEND ]; then
+ exit_with_hooks 0
+fi
+
+if [ x$reason = xBOUND ] || [ x$reason = xRENEW ] || \
+ [ x$reason = xREBIND ] || [ x$reason = xREBOOT ]; then
+ current_hostname=`hostname`
+ if [ x$current_hostname = x ] || \
+ [ x$current_hostname = x$old_host_name ]; then
+ if [ x$current_hostname = x ] || \
+ [ x$new_host_name != x$old_host_name ]; then
+ hostname $new_host_name
+ fi
+ fi
+
+ if [ x$old_ip_address != x ] && [ x$alias_ip_address != x ] && \
+ [ x$alias_ip_address != x$old_ip_address ]; then
+ # Possible new alias. Remove old alias.
+ ifconfig $interface:0- inet 0
+ fi
+ if [ x$old_ip_address != x ] && [ x$old_ip_address != x$new_ip_address ]; then
+ # IP address changed. Bringing down the interface will delete all routes,
+ # and clear the ARP cache.
+ ifconfig $interface inet 0 down
+
+ fi
+ if [ x$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_subnet_arg \
+ $new_broadcast_arg
+ # Add a network route to the computed network address.
+ if [ $relmajor -lt 2 ] || \
+ ( [ $relmajor -eq 2 ] && [ $relminor -eq 0 ] ); then
+ route add -net $new_network_number $new_subnet_arg dev $interface
+ fi
+ for router in $new_routers; do
+ route add default gw $router
+ done
+ fi
+ if [ x$new_ip_address != x$alias_ip_address ] && [ x$alias_ip_address != x ];
+ then
+ ifconfig $interface:0- inet 0
+ ifconfig $interface:0 inet $alias_ip_address $alias_subnet_arg
+ route add -host $alias_ip_address $interface:0
+ fi
+ make_resolv_conf
+ exit_with_hooks 0
+fi
+
+if [ x$reason = xEXPIRE ] || [ x$reason = xFAIL ] || [ x$reason = xRELEASE ] \
+ || [ x$reason = xSTOP ]; then
+ if [ x$alias_ip_address != x ]; then
+ # Turn off alias interface.
+ ifconfig $interface:0- inet 0
+ fi
+ if [ x$old_ip_address != x ]; then
+ # Shut down interface, which will delete routes and clear arp cache.
+ ifconfig $interface inet 0 down
+ fi
+ if [ x$alias_ip_address != x ]; then
+ ifconfig $interface:0 inet $alias_ip_address $alias_subnet_arg
+ route add -host $alias_ip_address $interface:0
+ fi
+ exit_with_hooks 0
+fi
+
+if [ x$reason = xTIMEOUT ]; then
+ if [ x$alias_ip_address != x ]; then
+ ifconfig $interface:0- inet 0
+ fi
+ ifconfig $interface inet $new_ip_address $new_subnet_arg \
+ $new_broadcast_arg
+ set $new_routers
+ ############## what is -w in ping?
+ if ping -q -c 1 $1; then
+ if [ x$new_ip_address != x$alias_ip_address ] && \
+ [ x$alias_ip_address != x ]; then
+ ifconfig $interface:0 inet $alias_ip_address $alias_subnet_arg
+ route add -host $alias_ip_address dev $interface:0
+ fi
+ if [ $relmajor -lt 2 ] || \
+ ( [ $relmajor -eq 2 ] && [ $relminor -eq 0 ] ); then
+ route add -net $new_network_number
+ fi
+ for router in $new_routers; do
+ route add default gw $router
+ done
+ make_resolv_conf
+ exit_with_hooks 0
+ fi
+ ifconfig $interface inet 0 down
+ exit_with_hooks 1
+fi
+
+exit_with_hooks 0