#!/bin/bash
#
# This script is triggered by udhcpc in stage3 and handle the
# DHCP information given as parameters
{
# for debugging
set -x
NETWORK_CONF="/run/openslx/network.conf"
. "$NETWORK_CONF"
MAIN_NETIF="$SLX_PXE_NETIF"
[ -n "$SLX_VLAN_ID" ] && MAIN_NETIF="${SLX_PXE_NETIF}.${SLX_VLAN_ID}"
[ -n "$SLX_BRIDGE" ] && MAIN_NETIF="$SLX_BRIDGE"
readonly MAIN_NETIF
if [[ "$1" != "bound" && "$1" != "renew" ]] \
|| [ "$interface" != "${MAIN_NETIF}" ] \
|| [ -z "$ip" ]; then
exit 0
fi
log() {
echo "${MAIN_NETIF}: $*"
}
##
## CORE NETWORK CONFIGURATION
##
## > IP, subnet, route
# If we already got an IP from KCL, see if it differs, and remove first if so
# We just try to prevent everything from breaking if the DHCP server doesn't
# objey the renew request by the client and hands out a new address
if [ -n "$SLX_PXE_CLIENT_IP" ]; then
#...some address is already configured...
if [ "${SLX_PXE_CLIENT_IP}" != "${ip}" ]; then
#...it's a different one, reconfigure...
log "reconfiguring from '${SLX_PXE_CLIENT_IP}' to '${ip}'"
# remove default route and let it be added again below, as it might get lost when changing the primary address on the interface
ip route del default
ip addr del "$SLX_PXE_CLIENT_IP" dev "${interface}"
fi
else
#...no address configured yet, just add...
log "adding ${ip}"
fi
if ! ip addr show dev "${interface}" | grep -qF "inet ${ip}/"; then
ip addr add "${ip}/$(ipcalc -s -p "${ip}" "${subnet}" | sed s/.*=//)" dev "${interface}"
echo "SLX_DHCP_CLIENT_IP='$ip'" >> "$NETWORK_CONF"
fi
# Same procedure for default gateway
if [ -n "$router" ]; then
if [ -n "$SLX_PXE_GATEWAY" ] && [ "$SLX_PXE_GATEWAY" != "$router" ]; then
log "reconfiguring default gw from '$SLX_PXE_GATEWAY' to '$router'"
ip route del default
fi
ip route add default via "$router" dev "${MAIN_NETIF}"
echo "SLX_DHCP_GATEWAY='$router'" >> "$NETWORK_CONF"
fi
##
## ADDITIONAL NETWORK CONFIGURATION
##
## > DNS, domain, hostname
rm -f -- "/etc/resolv.conf"
reverse_lookup() {
[ -z "$dns" ] && return
[ -z "$1" ] && return
timeout 3 nslookup "$1" | awk '{
if ($2 == "name") { print gensub("\\.$", "", 1, $4); exit; }
if ($1 == "Name:") { ok = 1 }
if (ok && $1 == "Address") { print gensub("\\.$", "", 1, $4); exit; }
}'
}
echo "# From DHCP in stage 3.1" >> "$NETWORK_CONF"
# DNS/domain?
if [ -n "$dns" ]; then
log "DNS servers: $dns"
echo "SLX_DNS='$dns'" >> "$NETWORK_CONF"
for srv in $dns; do
echo "nameserver $srv" >> "/etc/resolv.conf"
done
else
dns="$( < /etc/resolv.conf awk '$1 == "nameserver" {printf "%s ", $2}' )"
fi
# always check DNS
log "checking reverse DNS record for this host"
[ -n "$fqdn" ] && [[ "$fqdn" != *.* ]] && fqdn=
[ -z "$fqdn" ] && fqdn="$( reverse_lookup "$ip" )"
[ -z "$fqdn" ] && [ -n "$hostname" ] && [ -n "$domain" ] && fqdn="${hostname}.${domain}"
# retry DNS one time
if [ -z "$fqdn" ]; then
log "found no way to generate FQDN, trying reverse lookup one more time"
sleep 1
fqdn="$( reverse_lookup "$ip" )"
fi
if [ -n "$fqdn" ]; then
fqdn_hostname="${fqdn%%.*}"
fqdn_domain="${fqdn#*.}"
fi
if [ -z "$hostname" ] && [ -n "$fqdn_hostname" ]; then
hostname="${fqdn_hostname}"
log "using hostname from DNS, as DHCP didn't supply one"
fi
if [ -z "$hostname" ] && [ -n "$SLX_PXE_HOSTNAME" ]; then
hostname="$SLX_PXE_HOSTNAME"
log "using hostname from KCL, as DHCP/DNS didn't supply one"
fi
if [ -z "$hostname" ]; then
hostname="noname-${ip//./-}"
log "got no hostname via DHCP, DNS or KCL, using fallback '$hostname'"
fi
if [ -z "$domain" ] && [ -n "$fqdn_domain" ]; then
domain="${fqdn_domain}"
log "using domain from DNS, as DHCP didn't supply one"
fi
domain="${domain%% *}" # in case domain is a list, some DHCP servers did that in the past instead of using search
# Normalize to lowercase
for var in hostname domain fqdn search fqdn_hostname fqdn_domain SLX_PXE_HOSTNAME; do
declare "$var"="${!var~~}"
done
# Add domain to list of search domains if not in there yet
if [ -n "$domain" ] && [ -n "$search" ]; then
FOUND=no
for sd in $search; do
[ "$sd" = "$domain" ] && FOUND=yes
done
[ "$FOUND" = "no" ] && search="$domain $search"
elif [ -n "$domain" ]; then
search="$domain"
fi
# Write out
if [ -n "$domain" ]; then
echo "domain $domain" >> "/etc/resolv.conf"
echo "SLX_NET_DOMAIN='$domain'" >> "$NETWORK_CONF"
fi
if [ -n "$search" ]; then
echo "search $search" >> "/etc/resolv.conf"
echo "SLX_NET_SEARCH='$search'" >> "$NETWORK_CONF"
fi
if [ -n "$ntpsrv" ]; then
echo "SLX_DHCP_NTP='$ntpsrv'" >> "$NETWORK_CONF"
fi
declare -a localnames=()
[ -n "$fqdn" ] && localnames+=( "$fqdn" )
[ -n "$hostname" ] && localnames+=( "$hostname" )
[ -n "$fqdn_hostname" ] && [ "$hostname" != "$fqdn_hostname" ] && localnames+=( "$fqdn_hostname" )
[ -n "$SLX_PXE_HOSTNAME" ] && [ "$hostname" != "$SLX_PXE_HOSTNAME" ] && localnames+=( "$SLX_PXE_HOSTNAME" )
{
echo "127.0.0.1 localhost"
echo "127.0.1.1 ${localnames[*]}"
} > "/etc/hosts"
log "setting hostname $hostname, FQDN $fqdn"
echo "$hostname" > "/proc/sys/kernel/hostname"
echo "$hostname" > "/etc/hostname"
echo "SLX_HOSTNAME='$hostname'" >> "$NETWORK_CONF"
touch /.network
set +x
} {BASH_XTRACEFD}> "/run/openslx/initramfs-udhcpc.log.$$"
