test: Increase time limit for IP creation in an HS test.

This should avoid most intermittent test failures on developer and CI machines,
but there could (and probably should) be a more elegant solution.

Also, this test was testing that the IP was created and its expiration time was
set to a time greater than or equal to `now+INTRO_POINT_LIFETIME_MIN_SECONDS+5`:

    /* Time to expire MUST also be in that range. We add 5 seconds because
     * there could be a gap between setting now and the time taken in
     * service_intro_point_new. On ARM, it can be surprisingly slow... */
    tt_u64_op(ip->time_to_expire, OP_GE,
              now + INTRO_POINT_LIFETIME_MIN_SECONDS + 5);

However, this appears to be a typo, since, according to the comment above it,
adding five seconds was done because the IP creation can be slow on some
systems.  But the five seconds is added to the *minimum* time we're comparing
against, and so it actually functions to make this test *more* likely to fail on
slower systems.  (It should either subtract five seconds, or instead add it to
time_to_expire.)

 * FIXES #25450: https://bugs.torproject.org/25450

changes/bug25450

@@ -0,0 +1,9 @@
+  o Minor bugfixes (testing):
+    - Avoid intermittent test failures due to relying on hidden service
+      introductory point creation within 5 seconds of real clock time.  The
+      time limit for the test has been increased to 500 seconds, which may
+      still result in intermittent failures (e.g. if the system doing the
+      testing enters sleep/hibernation or experiences some other clock jump).
+      However, this should elliminate test failures currently happening on
+      developer and CI systems.  Fixes bug 25450 (shoddily); bugfix on
+      0.3.1.3-alpha.

src/test/test_hs_service.c

@@ -413,13 +413,14 @@ test_service_intro_point(void *arg)
               INTRO_POINT_MIN_LIFETIME_INTRODUCTIONS);
     tt_u64_op(ip->introduce2_max, OP_LE,
               INTRO_POINT_MAX_LIFETIME_INTRODUCTIONS);
-    /* Time to expire MUST also be in that range. We add 5 seconds because
-     * there could be a gap between setting now and the time taken in
-     * service_intro_point_new. On ARM, it can be surprisingly slow... */
+    /* Time to expire MUST also be in that range. We subtract 500 seconds
+     * because there could be a gap between setting now and the time taken in
+     * service_intro_point_new. On ARM and other older CPUs, it can be
+     * surprisingly slow... */
     tt_u64_op(ip->time_to_expire, OP_GE,
-              now + INTRO_POINT_LIFETIME_MIN_SECONDS + 5);
+              now + INTRO_POINT_LIFETIME_MIN_SECONDS - 500);
     tt_u64_op(ip->time_to_expire, OP_LE,
-              now + INTRO_POINT_LIFETIME_MAX_SECONDS + 5);
+              now + INTRO_POINT_LIFETIME_MAX_SECONDS - 500);
     tt_assert(ip->replay_cache);
     tt_assert(ip->base.link_specifiers);
     /* By default, this is NOT a legacy object. */