From 2024ccca17e83c9615ac0157103fe3eb17365ceb Mon Sep 17 00:00:00 2001
From: Michael Tremer <michael.tremer@ipfire.org>
Date: Sat, 2 May 2015 21:26:00 +0000
Subject: [PATCH] dhclient: Properly handle IPv6

Router advertisements are now properly processed if there
is dhclient running on an interface and all information
from the DHCP client is removed when dhclient is stopped.
---
 src/dhclient-script          | 26 ++++++++++++++++++++++++++
 src/functions/functions.ipv6 | 23 +++++++++++++++++++++++
 2 files changed, 49 insertions(+)

diff --git a/src/dhclient-script b/src/dhclient-script
index 5c22539f..fd5c6f13 100644
--- a/src/dhclient-script
+++ b/src/dhclient-script
@@ -41,6 +41,13 @@ case "${reason}" in
 		# Flush all other aborted IP addresses
 		ipv6_address_flush "${interface}"
 
+		# Disable autoconf because DHCP is handling this
+		ipv6_device_autoconf_disable "${interface}"
+
+		# Enable forwarding because we are acting as a host
+		# to uplink network zones.
+		ipv6_device_forwarding_enable "${interface}" --accept-ra
+
 		# Wait until DAD for the link-local address has finished
 		for address in $(ipv6_device_get_addresses "${interface}" --scope="link"); do
 			ipv6_wait_for_dad "${address}" "${interface}" && exit ${EXIT_OK}
@@ -64,6 +71,9 @@ case "${reason}" in
 			db_set "${interface}/ipv6/active" 1
 			#db_set "${interface}/ipv6/domain-name" "${new_
 
+			# Update the routing tables
+			routing_update "${interface}" ipv6
+
 			exit 0
 
 		# Handle Prefix Delegation
@@ -105,6 +115,9 @@ case "${reason}" in
 			ipv6_address_add "${new_ip6_address}/${new_ip6_prefixlen}" "${interface}" \
 				--valid-lifetime="${new_max_life}" --preferred-lifetime="${new_preferred_life}"
 
+			# Update the routing tables
+			routing_update "${interface}" ipv6
+
 			exit ${EXIT_OK}
 
 		# Handle Prefix Delegation
@@ -132,6 +145,19 @@ case "${reason}" in
 			--preferred-lifetime=0 || exit ${EXIT_ERROR}
 		;;
 
+	EXPIRE6|FAIL6|RELEASE6|STOP6)
+		# Remove the currently configured addresses from the device.
+		ipv6_address_flush "${interface}"
+
+		# Reset autoconf mode and disable forwarding
+		ipv6_device_forwarding_disable "${interface}"
+		ipv6_device_autoconf_disable "${interface}"
+
+		db_delete "${interface}/ipv6"
+
+		exit 0
+		;;
+
 	# IPv4
 
 	PREINIT)
diff --git a/src/functions/functions.ipv6 b/src/functions/functions.ipv6
index 74e01c00..5e618dc5 100644
--- a/src/functions/functions.ipv6
+++ b/src/functions/functions.ipv6
@@ -53,10 +53,32 @@ ipv6_device_autoconf_disable() {
 
 ipv6_device_forwarding_enable() {
 	local device="${1}"
+	shift
+
+	local accept_ra=0
+
+	local arg
+	while read arg; do
+		case "${arg}" in
+			--accept-ra)
+				accept_ra=2
+				;;
+		esac
+	done <<< "$(args $@)"
 
 	sysctl_set "net.ipv6.conf.${device}.forwarding" 1
 
 	log INFO "Enabled IPv6 forwarding on '${device}'"
+
+	# If forwarding is enabled, the kernel won't process
+	# any router advertisements any more, which is not good
+	# when we still want a default route when running in
+	# DHCP client mode on an uplink zone.
+	if [ ${accept_ra} -gt 0 ]; then
+		log INFO "  and accepting router advertisements"
+
+		sysctl_set "net.ipv6.conf.${device}.accept_ra" 2
+	fi
 }
 
 ipv6_device_forwarding_disable() {
@@ -206,6 +228,7 @@ ipv6_address_flush() {
 
 	# Remove any stale addresses from aborted clients
 	cmd_quiet ip -6 addr flush dev "${device}" scope global permanent
+	cmd_quiet ip -6 addr flush dev "${device}" scope global dynamic
 }
 
 ipv6_address_change_lifetime() {
-- 
2.39.2