From b6946084296525f0e2aa3e72df7b896cc98197d7 Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Tue, 2 Jul 2019 15:03:47 +0200 Subject: [PATCH] ntpd: add comment about mode6, no code changes Signed-off-by: Denys Vlasenko --- networking/ntpd.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/networking/ntpd.c b/networking/ntpd.c index 465c74d6c..48dc1c379 100644 --- a/networking/ntpd.c +++ b/networking/ntpd.c @@ -2238,6 +2238,13 @@ recv_and_process_client_pkt(void /*int fd*/) from = xzalloc(to->len); size = recv_from_to(G_listen_fd, &msg, sizeof(msg), MSG_DONTWAIT, from, &to->u.sa, to->len); + + /* "ntpq -p" (4.2.8p13) sends a 12-byte NTPv2 request: + * m_status is 0x16: leap:0 version:2 mode:6(reserved1) + * https://docs.ntpsec.org/latest/mode6.html + * We don't support this. + */ + #if ENABLE_FEATURE_NTP_AUTH if (size != NTP_MSGSIZE_NOAUTH && size != NTP_MSGSIZE_MD5_AUTH && size != NTP_MSGSIZE_SHA1_AUTH) #else -- 2.25.1