#!/bin/bash # dhclient-script for Linux. Dan Halbert, March, 1997. # Updated for Linux 2.[12] by Brian J. Murrell, January 1999. # Modified for Debian. Matt Zimmerman and Eloy Paris, December 2003 # Modified to remove useless tests for antiquated kernel versions that # this doesn't even work with anyway, and introduces a dependency on /usr # being mounted, which causes cosmetic errors on hosts that NFS mount /usr # Andrew Pollock, February 2005 # Modified to work on point-to-point links. Andrew Pollock, June 2005 # Modified to support passing the parameters called with to the hooks. Andrew Pollock, November 2005 # The alias handling in here probably still sucks. -mdz make_resolv_conf() { if [ "$new_domain_name" -o "$new_domain_name_servers" ]; then # Find out whether we are going to mount / rw exec 9>&0 &9 9>&- # Wait for /etc/resolv.conf to become writable if [ "$rootmode" = "rw" ]; then while [ ! -w /etc ]; do sleep 0.1 done fi fi if [ "$new_domain_name" -o "$new_domain_search" \ -o "$new_domain_name_servers" ]; then local new_resolv_conf=/etc/resolv.conf.dhclient-new rm -f $new_resolv_conf if [ "$new_domain_name_servers" ]; then for nameserver in $new_domain_name_servers; do echo nameserver $nameserver >>$new_resolv_conf done else # keep 'old' nameservers sed -n /^\w*[Nn][Aa][Mm][Ee][Ss][Ee][Rr][Vv][Ee][Rr]/p /etc/resolv.conf >>$new_resolv_conf fi if [ "$new_domain_name" ]; then echo domain ${new_domain_name%% *} >>$new_resolv_conf fi if [ "$new_domain_search" ]; then if [ "$new_domain_name" ]; then domain_in_search_list="" for domain in "$new_domain_search"; do if [ "$domain" = "$new_domain_name" ]; then domain_in_search="Yes" fi done if [ ! "$domain_in_search" ]; then new_domain_search="$new_domain_name $new_domain_search" fi fi echo "search ${new_domain_search}" >> $new_resolv_conf elif [ "$new_domain_name" ]; then echo "search ${new_domain_name}" >> $new_resolv_conf fi chown --reference=/etc/resolv.conf $new_resolv_conf chmod --reference=/etc/resolv.conf $new_resolv_conf mv -f $new_resolv_conf /etc/resolv.conf fi } run_hook() { local script="$1" local exit_status shift # discard the first argument, then the rest are the script's if [ -f $script ]; then . $script "$@" fi if [ -n "$exit_status" ] && [ "$exit_status" -ne 0 ]; then logger -p daemon.err "$script returned non-zero exit status $exit_status" save_exit_status=$exit_status fi return $exit_status } run_hookdir() { local dir="$1" local exit_status shift # See run_hook if [ -d "$dir" ]; then for script in $(run-parts --list $dir); do run_hook $script "$@" || true exit_status=$? done fi return $exit_status } # Must be used on exit. Invokes the local dhcp client exit hooks, if any. exit_with_hooks() { exit_status=$1 # Source the documented exit-hook script, if it exists if ! run_hook /etc/dhcp3/dhclient-exit-hooks "$@"; then exit_status=$? fi # Now run scripts in the Debian-specific directory. if ! run_hookdir /etc/dhcp3/dhclient-exit-hooks.d "$@"; then exit_status=$? fi exit $exit_status } if [ -n "$new_broadcast_address" ]; then new_broadcast_arg="broadcast $new_broadcast_address" fi if [ -n "$old_broadcast_address" ]; then old_broadcast_arg="broadcast $old_broadcast_address" fi if [ -n "$new_subnet_mask" ]; then new_subnet_arg="netmask $new_subnet_mask" fi if [ -n "$old_subnet_mask" ]; then old_subnet_arg="netmask $old_subnet_mask" fi if [ -n "$alias_subnet_mask" ]; then alias_subnet_arg="netmask $alias_subnet_mask" fi # The 576 MTU is only used for X.25 and dialup connections # where the admin wants low latency. Such a low MTU can cause # problems with UDP traffic, among other things. As such, # disallow MTUs from 576 and below by default, so that broken # MTUs are ignored, but higher stuff is allowed (1492, 1500, etc). if [ -n "$new_interface_mtu" ] && [ $new_interface_mtu -gt 576 ]; then mtu_arg="mtu $new_interface_mtu" fi if [ -n "$IF_METRIC" ]; then metric_arg="metric $IF_METRIC" # interfaces(5), "metric" option fi # The action starts here # Invoke the local dhcp client enter hooks, if they exist. run_hook /etc/dhcp3/dhclient-enter-hooks run_hookdir /etc/dhcp3/dhclient-enter-hooks.d # Execute the operation case "$reason" in MEDIUM|ARPCHECK|ARPSEND) # Do nothing ;; PREINIT) # The DHCP client is requesting that an interface be # configured as required in order to send packets prior to # receiving an actual address. - dhclient-script(8) if [ -n "$alias_ip_address" ]; then # Bring down alias interface. Its routes will disappear too. ifconfig $interface:0- inet 0 fi ifconfig $interface inet 0 up ;; BOUND|RENEW|REBIND|REBOOT) if [ -n "$new_host_name" ]; then if [ ! -s /etc/hostname ]; then hostname "$new_host_name" fi fi if [ -n "$old_ip_address" -a -n "$alias_ip_address" -a \ "$alias_ip_address" != "$old_ip_address" ]; then # Possible new alias. Remove old alias. ifconfig $interface:0- inet 0 fi if [ -n "$old_ip_address" -a \ "$old_ip_address" != "$new_ip_address" ]; then # IP address changed. Bringing down the interface will delete all routes, # and clear the ARP cache. ifconfig $interface inet 0 fi if [ -z "$old_ip_address" -o "$old_ip_address" != "$new_ip_address" -o \ "$reason" = "BOUND" -o "$reason" = "REBOOT" ]; then ifconfig $interface inet $new_ip_address $new_subnet_arg \ $new_broadcast_arg $mtu_arg # point to point if [ "$new_subnet_mask" == "255.255.255.255" ]; then for router in $new_routers; do route add -host $router dev $interface done fi for router in $new_routers; do route add default dev $interface gw $router $metric_arg done fi if [ "$new_ip_address" != "$alias_ip_address" -a -n "$alias_ip_address" ]; then ifconfig $interface:0- inet 0 ifconfig $interface:0 inet $alias_ip_address $alias_subnet_arg route add -host $alias_ip_address $interface:0 fi make_resolv_conf ;; EXPIRE|FAIL|RELEASE|STOP) if [ -n "$alias_ip_address" ]; then # Turn off alias interface. ifconfig $interface:0- inet 0 fi if [ -n "$old_ip_address" ]; then # Shut down interface, which will delete routes and clear arp cache. ifconfig $interface inet 0 fi if [ -n "$alias_ip_address" ]; then ifconfig $interface:0 inet $alias_ip_address $alias_subnet_arg route add -host $alias_ip_address $interface:0 fi ;; TIMEOUT) if [ -n "$alias_ip_address" ]; then ifconfig $interface:0- inet 0 fi ifconfig $interface inet $new_ip_address $new_subnet_arg \ $new_broadcast_arg $mtu_arg set -- $new_routers first_router="$1" if [ -z "$first_router" ] || ping -q -c 1 $first_router; then if [ "$new_ip_address" != "$alias_ip_address" -a \ -n "$alias_ip_address" ]; then ifconfig $interface:0 inet $alias_ip_address $alias_subnet_arg route add -host $alias_ip_address dev $interface:0 fi for router in $new_routers; do route add default dev $interface gw $router $metric_arg done make_resolv_conf else # Changed from 'ifconfig $interface inet 0 down' - see Debian bug #144666 ifconfig $interface inet 0 exit_with_hooks 2 "$@" fi ;; esac exit_with_hooks 0