git: 069681afd58a - main - ping: use CLOCK_REALTIME for ICMP Originate Timestamp

The branch main has been updated by maxim:

URL: https://cgit.FreeBSD.org/src/commit/?id=069681afd58a711eb7407be4a9c9a05f787d250f

commit 069681afd58a711eb7407be4a9c9a05f787d250f
Author:     Maxim Konovalov <maxim@FreeBSD.org>
AuthorDate: 2026-05-01 17:45:27 +0000
Commit:     Maxim Konovalov <maxim@FreeBSD.org>
CommitDate: 2026-05-02 03:16:55 +0000

    ping: use CLOCK_REALTIME for ICMP Originate Timestamp
    
    RFC 792 defines the ICMP Originate Timestamp field as milliseconds
    since midnight UTC.  However, ping(8) currently derives this value
    from CLOCK_MONOTONIC, which represents time since an unspecified
    starting point and is not related to UTC.
    
    The issue was introduced by commit 1ad76f1b6047, which replaced
    gettimeofday(2) with clock_gettime(CLOCK_MONOTONIC) for timekeeping
    in ping(8).
    
    Fix this by using CLOCK_REALTIME when generating the ICMP originate
    timestamp.
    
    Before:
    
    $ ping -Mt -c1 127.0.0.1
    ICMP_TSTAMP
    PING 127.0.0.1 (127.0.0.1): 56 data bytes
    <...> time=0.061 ms tso=16:50:31 tsr=17:38:28 tst=17:38:28
    
    (note the tso is off)
    
    After:
    
    $ ping -Mt -c1 127.0.0.1
    ICMP_TSTAMP
    PING 127.0.0.1 (127.0.0.1): 56 data bytes
    <...> time=0.038 ms tso=17:42:09 tsr=17:42:09 tst=17:42:09
    
    Reviewed by:            asomers, glebius
    Fixes:                  1ad76f1b6047
    MFC after:              1 month
    Differential Revision:  https://reviews.freebsd.org/D56759
---
 sbin/ping/ping.c             |  9 ++++++++-
 sbin/ping/tests/ping_test.sh | 35 +++++++++++++++++++++++++++++++++++
 2 files changed, 43 insertions(+), 1 deletion(-)

diff --git a/sbin/ping/ping.c b/sbin/ping/ping.c
index d10e3c85c9bd..579ecb9151bb 100644
--- a/sbin/ping/ping.c
+++ b/sbin/ping/ping.c
@@ -1029,9 +1029,16 @@ pinger(void)
 		 */
 		tv32.tv32_sec = (uint32_t)htonl(now.tv_sec);
 		tv32.tv32_nsec = (uint32_t)htonl(now.tv_nsec);
-		if (options & F_TIME)
+		if (options & F_TIME) {
+			/*
+			 * However, per RFC 792 the Originate Timestamp (otime)
+			 * should be milliseconds since midnight UTC. Something,
+			 * that CLOCK_MONOTONIC does not guarantee.
+			 */
+			(void)clock_gettime(CLOCK_REALTIME, &now);
 			icp.icmp_otime = htonl((now.tv_sec % (24*60*60))
 				* 1000 + now.tv_nsec / 1000000);
+		}
 		if (timing)
 			bcopy((void *)&tv32,
 			    (void *)&outpack[ICMP_MINLEN + phdr_len],
diff --git a/sbin/ping/tests/ping_test.sh b/sbin/ping/tests/ping_test.sh
index 5a12ace104d7..6e090cfd945a 100644
--- a/sbin/ping/tests/ping_test.sh
+++ b/sbin/ping/tests/ping_test.sh
@@ -253,6 +253,40 @@ inject_reply_cleanup()
 	ifconfig `cat tun.txt` destroy
 }
 
+atf_test_case timestamp_origin
+timestamp_origin_head()
+{
+	atf_set "descr" "ICMP Originate Timestamp"
+}
+timestamp_origin_body()
+{
+	require_ipv4
+	# Run ping timestamp
+	out=$(ping -Mt -c1 127.0.0.1)
+
+	# Extract tso and tsr
+	tso=$(echo "$out" | sed -n 's/.*tso=\([0-9:]*\).*/\1/p')
+	tsr=$(echo "$out" | sed -n 's/.*tsr=\([0-9:]*\).*/\1/p')
+
+	atf_check test -n "$tso"
+	atf_check test -n "$tsr"
+
+	# Convert tso and tsr from HH:MM:SS to seconds
+	tso_s=`date -jf %H:%M:%S $tso`
+	tsr_s=`date -jf %H:%M:%S $tsr`
+
+	diff=$((tso_s - tsr_s))
+	# Tolerate negative time difference between the sender and receiver
+	if [ $diff -lt 0 ]; then
+		diff=$(( -diff ))
+	fi
+
+	# Tolerate 2 seconds difference
+	if [ $diff -gt 2 ]; then
+		atf_fail "tso ($tso) differs from tsr ($tsr) by $diff seconds"
+	fi
+}
+
 atf_init_test_cases()
 {
 	atf_add_test_case ping_c1_s56_t1
@@ -271,6 +305,7 @@ atf_init_test_cases()
 	atf_add_test_case inject_opts
 	atf_add_test_case inject_pip
 	atf_add_test_case inject_reply
+	atf_add_test_case timestamp_origin
 }
 
 check_ping_statistics()