---
loader2/linuxrc.s390 | 44 +++++++++++++++++++++++++++++++++++++++++---
1 files changed, 41 insertions(+), 3 deletions(-)
diff --git a/loader2/linuxrc.s390 b/loader2/linuxrc.s390
index e22d4ac..a401986 100644
--- a/loader2/linuxrc.s390
+++ b/loader2/linuxrc.s390
@@ -59,6 +59,24 @@ checkipv4()
return $?
}
+checkdns()
+{
+ dns=$1
+ # DNS syntax is addr1:addr2:addr3 so first split by ":"
+ dnslist=$(echo $dns | awk -F ':' '{i=1; while (i<=NF) {print $i; i=i+1}}')
+ found=0
+ for i in $dnslist; do
+ # note: only support ipv4 DNS currently,
+ # since both ipv6 address and DNS= parameter can contain ":"
+ checkipv4 $i
+ [ $? -eq 1 ]&& return 1
+ # track whether we've found at least one valid IP
+ found=1
+ done
+ [ $found -eq 1 ]&& return 0
+ return 1
+}
+
doshutdown()
{
exec /sbin/shutdown
@@ -531,9 +549,29 @@ fi
# BH FIXME: Workaround for manual MACADDR, need ping to update arp table
ping -c 1 $GATEWAY> /dev/null
- if [ -z "$DNS" ]; then
- echo $"Enter your DNS server(s), separated by colons (:):"
- read DNS
+
+ # DNS is optional, but if specified it must be correct
+ if [ -n "$DNS" ]; then
+ checkdns $DNS
+ ret=$?
+ if [ $ret -ne 0 ]; then
+ echo $"You have an invalid predefined DNS list"
+ fi
+ fi
+ if [ -z "$DNS" ] || [ $ret -ne 0 ]; then
+ echo $"Enter your DNS server(s), separated by colons (:)"
+ echo $"Leave this blank and press enter to skip"
+ read DNS
+ checkdns $DNS
+ ret=$?
+ while [ -n "$DNS" ]&& [ $ret -ne 0 ]; do
+ echo -n "Invalid DNS address format. "
+ echo $"Enter your DNS server(s), separated by colons (:)"
+ echo $"Leave this blank and press enter to skip"
+ read DNS
+ checkdns $DNS
+ ret=$?
+ done
fi
if [ -z "$DNS" ]; then
echo $"You might encounter problems without a nameserver, especially"