Distinguish true clock jumps from idleness

Since we're going to be disabling the second-elapsed callback, we're
going to sometimes have long periods when no events file, and so the
current second is not updated.  Handle that by having a better means
to detect "clock jumps" as opposed to "being idle for a while".
Tolerate far more of the latter.

Part of #26009.

1 files changed, 18 insertions, 10 deletions

diff --git a/src/or/circuitbuild.c b/src/or/circuitbuild.c
index 24c32b710c..0617c24776 100644
--- a/src/or/circuitbuild.c
+++ b/src/or/circuitbuild.c
@@ -1133,19 +1133,27 @@ circuit_send_intermediate_onion_skin(origin_circuit_t *circ,
   return 0;
 }
 
-/** Our clock just jumped by <b>seconds_elapsed</b>. Assume
- * something has also gone wrong with our network: notify the user,
- * and abandon all not-yet-used circuits. */
+/** Our clock just jumped by <b>seconds_elapsed</b>. If <b>was_idle</b> is
+ * true, then the monotonic time matches; otherwise it doesn't. Assume
+ * something has also gone wrong with our network: notify the user, and
+ * abandon all not-yet-used circuits. */
 void
-circuit_note_clock_jumped(int seconds_elapsed)
+circuit_note_clock_jumped(int seconds_elapsed, bool was_idle)
 {
   int severity = server_mode(get_options()) ? LOG_WARN : LOG_NOTICE;
-  tor_log(severity, LD_GENERAL, "Your system clock just jumped %d seconds %s; "
-      "assuming established circuits no longer work.",
-      seconds_elapsed >=0 ? seconds_elapsed : -seconds_elapsed,
-      seconds_elapsed >=0 ? "forward" : "backward");
-  control_event_general_status(LOG_WARN, "CLOCK_JUMPED TIME=%d",
-                               seconds_elapsed);
+  if (was_idle) {
+    tor_log(severity, LD_GENERAL, "Tor has been idle for %d seconds; "
+            "assuming established circuits no longer work.",
+            seconds_elapsed);
+  } else {
+    tor_log(severity, LD_GENERAL,
+            "Your system clock just jumped %d seconds %s; "
+            "assuming established circuits no longer work.",
+            seconds_elapsed >=0 ? seconds_elapsed : -seconds_elapsed,
+            seconds_elapsed >=0 ? "forward" : "backward");
+  }
+  control_event_general_status(LOG_WARN, "CLOCK_JUMPED TIME=%d IDLE=%d",
+                               seconds_elapsed, was_idle?1:0);
   /* so we log when it works again */
   note_that_we_maybe_cant_complete_circuits();
   control_event_client_status(severity, "CIRCUIT_NOT_ESTABLISHED REASON=%s",