aiccu: add NTP sync check

This check tries to wait for NTP daemon to synchronise clock to lower stratum
than 16 before running the aiccu binary. In case timeout (configurable
in new option ntpsynctimeout; default is 90 seconds) is reached, the
AICCU is run neverrtheless. This makes the new script compliant with
some corner case scenarios like not using Busybox NTPd or not using NTPd
at all, maintaining maximum out-of-the box functionality.

Signed-off-by: Ondrej Caletka <Ondrej@Caletka.cz>

ipv6/aiccu/files/aiccu.sh

@@ -14,8 +14,8 @@ proto_aiccu_setup() {
 	local iface="$2"
 	local link="aiccu-$cfg"
 
-	local username password protocol server ip6prefix tunnelid requiretls defaultroute nat heartbeat verbose sourcerouting ip6addr
-	json_get_vars username password protocol server ip6prefix tunnelid requiretls defaultroute nat heartbeat verbose sourcerouting ip6addr
+	local username password protocol server ip6prefix tunnelid requiretls defaultroute nat heartbeat verbose sourcerouting ip6addr ntpsynctimeout
+	json_get_vars username password protocol server ip6prefix tunnelid requiretls defaultroute nat heartbeat verbose sourcerouting ip6addr ntpsynctimeout
 
 	[ -z "$username" -o -z "$password" ] && {
 		proto_notify_error "$cfg" "MISSING_USERNAME_OR_PASSWORD"
@@ -27,6 +27,7 @@ proto_aiccu_setup() {
 
 	CFGFILE="/var/etc/${link}.conf"
 	PIDFILE="/var/run/${link}.pid"
+	NTPSTRATUMFILE="/var/run/aiccu_ntp_stratum"
 	mkdir -p /var/run /var/etc
 
 	echo "username $username" > "$CFGFILE"
@@ -43,6 +44,15 @@ proto_aiccu_setup() {
 	echo "daemonize true" >> "$CFGFILE"
 	echo "pidfile $PIDFILE" >> "$CFGFILE"
 
+	# By default, wait at most 90 seconds for NTP sync
+	[ -z "$ntpsynctimeout" ] && ntpsynctimeout=90
+	for i in $(seq 1 $ntpsynctimeout); do
+		[ -f "$NTPSTRATUMFILE" ] && \
+		[ "$(cat $NTPSTRATUMFILE)" -lt 16 ] && \
+		echo "NTP synced, stratum $(cat $NTPSTRATUMFILE)" && break
+		[ "$(( $i % 10 ))" -eq 0 ] && echo "Waiting ${i} secs for NTP sync..."
+		sleep 1
+	done
 
 	aiccu start "$CFGFILE"
 
@@ -99,6 +109,7 @@ proto_aiccu_init_config() {
 	proto_config_add_boolean "nat"
 	proto_config_add_boolean "heartbeat"
 	proto_config_add_boolean "verbose"
+	proto_config_add_int "ntpsynctimeout"
 }
 
 [ -n "$INCLUDE_ONLY" ] || {