Change dhcp_request() and v4_config() to be able to configure dhcp

for an interface without an active network connection.

- Don't write options to dhclient.conf that are default. Only use
  the 'host-name' option for hostname associated dhcp requests.

- Run dhclient with options to reduce the time it takes to finish
  in case it gets no answer from a DHCP server.

- Don't bother removing the interface from group dhcp and save the
  configuration files even if dhclient fails. If the same interface
  is statically configured later, it is removed from the group dhcp.

- Add 'dhcp' to hostname.if file regardless whether dhcp_request()
  was successful or not.

- Change the Netmask question to be more autoinstaller friendly.

based on krw's work
discussed with and OK krw@

1 files changed, 18 insertions, 28 deletions

diff --git a/distrib/miniroot/install.sub b/distrib/miniroot/install.sub
index 865153bedb5..baa26896e7d 100644
--- a/distrib/miniroot/install.sub
+++ b/distrib/miniroot/install.sub
@@ -1,4 +1,4 @@
-#	$OpenBSD: install.sub,v 1.765 2014/04/21 15:56:19 rpe Exp $
+#	$OpenBSD: install.sub,v 1.766 2014/04/21 19:05:40 rpe Exp $
 #
 # Copyright (c) 1997-2009 Todd Miller, Theo de Raadt, Ken Westerback
 # All rights reserved.
@@ -780,40 +780,29 @@ dhclient() {
 	/sbin/dhclient "$@"
 }
 
-# Construct etc/dhclient.conf and issue DHCP request. Return FALSE if
-# no IP address assigned to $1.
-#
-# $1 == interface
-# $2 == hostname
+# Issue a DHCP request to configure interface $1 and add the host-name option to
+# /etc/dhclient.conf using $2.
 dhcp_request() {
 	local _ifs=$1 _hn=$2
 
 	echo "lookup file bind" >/etc/resolv.conf.tail
+	echo "send host-name \"$_hn\";" >/etc/dhclient.conf
 
-	cat >/etc/dhclient.conf <<__EOT
+	ifconfig $_ifs group dhcp >/dev/null 2>&1
+
+	dhclient -c /dev/stdin $_ifs << __EOT
 initial-interval 1;
+backoff-cutoff 2;
+reboot 5;
+timeout 10;
 send host-name "$_hn";
-request subnet-mask, broadcast-address, routers, domain-name,
-	domain-name-servers, host-name;
 __EOT
 
-	ifconfig $_ifs group dhcp >/dev/null 2>&1
-	dhclient $_ifs
-
-	set -- $(v4_info $_ifs)
-
-	if [[ $1 == UP && -n $2 ]]; then
-		# Move configuration files to where they will be copied to the
-		# installed system. Overwrites configuration information from
-		# last successful dhcp attempt.
-		mv /etc/dhclient.conf /tmp/dhclient.conf
-		mv /etc/resolv.conf.tail /tmp/resolv.conf.tail
-		return 0
-	fi
-
-	ifconfig $_ifs delete down -group dhcp 2>/dev/null
-	rm /etc/dhclient.conf /etc/resolv.conf.tail
-	return 1
+	# Move configuration files to where they will be copied to the
+	# installed system. Overwrites configuration information from
+	# last successful dhcp attempt.
+	mv /etc/dhclient.conf /tmp/dhclient.conf
+	mv /etc/resolv.conf.tail /tmp/resolv.conf.tail
 }
 
 # Convert a hex value to dotted decimal format
@@ -926,12 +915,13 @@ v4_config() {
 	none)	;;
 	dhcp)	if [[ ! -x /sbin/dhclient ]]; then
 			echo "DHCP not possible - no /sbin/dhclient."
-		elif dhcp_request $_ifs "$_name"; then
+		else
+			dhcp_request $_ifs "$_name"
 			echo "dhcp" >>$_hn
 		fi
 		;;
 	*)	_addr=$resp
-		ask_until "Netmask?" "${_mask:=255.255.255.0}"
+		ask_until "Netmask for $_ifs?" "${_mask:=255.255.255.0}"
 		ifconfig $_ifs -group dhcp >/dev/null 2>&1
 		if ifconfig $_ifs inet $_addr netmask $resp up; then
 			addhostent "$_addr" "$_name"