modules.d/40network/dhclient-script.sh

   1 #!/bin/sh
   2 # -*- mode: shell-script; indent-tabs-mode: nil; sh-basic-offset: 4; -*-
   3 # ex: ts=8 sw=4 sts=4 et filetype=sh
   4
   5 setup_interface() {
   6     ip=$new_ip_address
   7     mtu=$new_interface_mtu
   8     mask=$new_subnet_mask
   9     bcast=$new_broadcast_address
  10     gw=${new_routers%%,*}
  11     domain=$new_domain_name
  12     search=$(printf "$new_domain_search")
  13     namesrv=$new_domain_name_servers
  14     hostname=$new_host_name
  15
  16     [ -f /tmp/net.$netif.override ] && . /tmp/net.$netif.override
  17
  18     # Taken from debian dhclient-script:
  19     # The 576 MTU is only used for X.25 and dialup connections
  20     # where the admin wants low latency.  Such a low MTU can cause
  21     # problems with UDP traffic, among other things.  As such,
  22     # disallow MTUs from 576 and below by default, so that broken
  23     # MTUs are ignored, but higher stuff is allowed (1492, 1500, etc).
  24     if [ -n "$mtu" ] && [ $mtu -gt 576 ] ; then
  25         if ! ip link set $netif mtu $mtu ; then
  26             ip link set $netif down
  27             ip link set $netif mtu $mtu
  28             ip link set $netif up
  29             wait_for_if_up $netif
  30         fi
  31     fi
  32
  33     ip addr add $ip${mask:+/$mask} ${bcast:+broadcast $bcast} dev $netif
  34
  35     [ -n "$gw" ] && echo ip route add default via $gw dev $netif > /tmp/net.$netif.gw
  36
  37     [ -n "${search}${domain}" ] && echo "search $search $domain" > /tmp/net.$netif.resolv.conf
  38     if  [ -n "$namesrv" ] ; then
  39         for s in $namesrv; do
  40             echo nameserver $s
  41         done
  42     fi >> /tmp/net.$netif.resolv.conf
  43
  44     # Note: hostname can be fqdn OR short hostname, so chop off any
  45     # trailing domain name and explicity add any domain if set.
  46     [ -n "$hostname" ] && echo "echo ${hostname%.$domain}${domain+.$domain} > /proc/sys/kernel/hostname" > /tmp/net.$netif.hostname
  47 }
  48
  49 PATH=/usr/sbin:/usr/bin:/sbin:/bin
  50
  51 export PS4="dhclient.$interface.$$ + "
  52 exec >>/run/initramfs/loginit.pipe 2>>/run/initramfs/loginit.pipe
  53 type getarg >/dev/null 2>&1 || . /lib/dracut-lib.sh
  54 type ip_to_var >/dev/null 2>&1 || . /lib/net-lib.sh
  55
  56 # We already need a set netif here
  57 netif=$interface
  58
  59 # Huh? Interface configured?
  60 [ -f "/tmp/net.$netif.up" ] && exit 0
  61
  62 case $reason in
  63     PREINIT)
  64         echo "dhcp: PREINIT $netif up"
  65         ip link set $netif up
  66         wait_for_if_up $netif
  67         ;;
  68     BOUND)
  69         echo "dhcp: BOND setting $netif"
  70         unset layer2
  71         if [ -f /sys/class/net/$netif/device/layer2 ]; then
  72             read layer2 < /sys/class/net/$netif/device/layer2
  73         fi
  74         if [ "$layer2" != "0" ]; then
  75             if ! arping -q -D -c 2 -I $netif $new_ip_address ; then
  76                 warn "Duplicate address detected for $new_ip_address while doing dhcp. retrying"
  77                 exit 1
  78             fi
  79         fi
  80         unset layer2
  81         setup_interface
  82         set | while read line; do
  83             [ "${line#new_}" = "$line" ] && continue
  84             echo "$line"
  85         done >/tmp/dhclient.$netif.dhcpopts
  86
  87         {
  88             echo '. /lib/net-lib.sh'
  89             echo "setup_net $netif"
  90             echo "source_hook initqueue/online $netif"
  91             [ -e /tmp/net.$netif.manualup ] || echo "/sbin/netroot $netif"
  92             echo "> /tmp/setup_net_$netif.ok"
  93             echo "rm -f $hookdir/initqueue/setup_net_$netif.sh"
  94         } > $hookdir/initqueue/setup_net_$netif.sh
  95
  96         echo "[ -f /tmp/setup_net_$netif.ok ]" > $hookdir/initqueue/finished/dhclient-$netif.sh
  97         >/tmp/net.$netif.up
  98         ;;
  99     *) echo "dhcp: $reason";;
 100 esac
 101
 102 exit 0