Adding IPv6 support on VENET interface for the etcnet-based VEs

--- etc/dists/scripts/etcnet-add_ip.sh
+++ etc/dists/scripts/etcnet-add_ip.sh
@@ -58,6 +58,25 @@ destroy_venet_config()
 		error "Cannot destroy $dir" ${VZ_FS_NO_DISK_SPACE}
 }
 
+del_ipv6_conf()
+{
+	local dir="$1"; shift
+
+	if [ -f "$dir/ipv6address" ]; then
+		rm -f "$dir/ipv6address" ||
+			error "Cannot remove $dir/ipv6address" ${VZ_FS_NO_DISK_SPACE}
+	fi
+
+	if [ -f "$dir/ipv6route" ]; then
+		rm -f "$dir/ipv6route" ||
+			error "Cannot remove $dir/ipv6route" ${VZ_FS_NO_DISK_SPACE}
+	fi
+
+	del_param ".tmp/$VENET_DEV/options" "CONFIG_IPV6=yes"
+
+}
+
+
 setup_network()
 {
 	# Purge old venet0 interface settings
@@ -74,6 +93,7 @@ setup_network()
 		echo '127.0.0.1	localhost.localdomain localhost' >"$HOSTFILE"
 }
 
+
 create_alias()
 {
 	local ip="$1"; shift
@@ -84,6 +104,24 @@ create_alias()
 		error "Cannot create .tmp/$VENET_DEV/ipv4address" ${VZ_FS_NO_DISK_SPACE}
 }
 
+add_ip6() {
+	local ip="$1"; shift
+	local mask="$1"; shift
+
+	[ "${IPV6}" != "yes" ] && return
+
+	if ! grep -qw "$ip" ".tmp/$VENET_DEV/ipv6address" 2>/dev/null; then
+		echo "2000::/3 dev $VENET_DEV" > ".tmp/$VENET_DEV/ipv6route" ||
+			error "Cannot create .tmp/$VENET_DEV/ipv6route" ${VZ_FS_NO_DISK_SPACE}
+
+		echo "$ip/$mask" >> ".tmp/$VENET_DEV/ipv6address" ||
+			error "Cannot create .tmp/$VENET_DEV/ipv6address" ${VZ_FS_NO_DISK_SPACE}
+
+		put_param ".tmp/$VENET_DEV/options" "CONFIG_IPV6" "yes"
+	fi
+}
+
+
 backup_configs()
 {
 	rm -rf .tmp && mkdir -p .tmp ||
@@ -125,8 +163,15 @@ add_ip()
 		local i=0 ipm
 		for ipm; do
 			ip_conv $ipm
-			i="$(find_unused_alias "$(($i+1))")"
-			create_alias "$_IP" "$_MASK" "$i"
+			if [ -z "$_IPV6ADDR" ]; then
+				i="$(find_unused_alias "$(($i+1))")"
+				create_alias "$_IP" "$_MASK" "$i"
+			else
+				if [ "$IPDELALL" = "yes" ]; then
+				     del_ipv6_conf "$VENET_DEV"
+				fi
+				add_ip6 "${_IP}" "${_MASK}"
+			fi
 		done
 
 		move_configs
--- etc/dists/scripts/etcnet-del_ip.sh
+++ etc/dists/scripts/etcnet-del_ip.sh
@@ -59,8 +59,18 @@ del_ip()
 	local ipm quoted
 	for ipm; do
 		ip_conv $ipm
+
 		quoted="$(quote_sed_regexp "$_IP/$_MASK")"
-		sed -i -e "/^$quoted/d" "$VENET_DEV/ipv4address"
+		if [ -n "$_IPV6ADDR" ]; then
+			sed -i -e "/^$quoted/d" "$VENET_DEV/ipv6address"
+			if [ ! -s "$VENET_DEV/ipv6address" ]; then
+				rm -f -- "$VENET_DEV/ipv6address"
+				rm -f -- "$VENET_DEV/ipv6route"
+				sed -i -e "/^CONFIG_IPV6/d" "$VENET_DEV/options"
+			fi
+		else
+			sed -i -e "/^$quoted/d" "$VENET_DEV/ipv4address"
+		fi
 		ip addr del dev "$VENET_DEV" "$_IP/$_MASK"
 	done