Merge remote-tracking branch 'neel/b25511-r4'

8 files changed, 106 insertions, 3 deletions

diff --git a/changes/ticket25511 b/changes/ticket25511
new file mode 100644
index 0000000000..0a24e265ca
--- /dev/null
+++ b/changes/ticket25511
@@ -0,0 +1,5 @@
+  o Minor features (control port):
+    - Introduce GETINFO "current-time/{local,utc}" to return the local
+      and UTC times respectively in ISO format. This helps a controller
+      like Tor Browser detect a time-related error. Closes ticket 25511.
+      Patch by Neel Chauhan.
diff --git a/src/common/compat_time.c b/src/common/compat_time.c
index b940447b67..966216768f 100644
--- a/src/common/compat_time.c
+++ b/src/common/compat_time.c
@@ -71,8 +71,8 @@ tor_sleep_msec(int msec)
 /** Set *timeval to the current time of day.  On error, log and terminate.
  * (Same as gettimeofday(timeval,NULL), but never returns -1.)
  */
-void
-tor_gettimeofday(struct timeval *timeval)
+MOCK_IMPL(void,
+tor_gettimeofday, (struct timeval *timeval))
 {
 #ifdef _WIN32
   /* Epoch bias copied from perl: number of units between windows epoch and
diff --git a/src/common/compat_time.h b/src/common/compat_time.h
index 75b57f6f24..09dd6add3d 100644
--- a/src/common/compat_time.h
+++ b/src/common/compat_time.h
@@ -173,7 +173,7 @@ void monotime_coarse_add_msec(monotime_coarse_t *out,
 #define monotime_coarse_add_msec monotime_add_msec
 #endif /* defined(MONOTIME_COARSE_TYPE_IS_DIFFERENT) */
 
-void tor_gettimeofday(struct timeval *timeval);
+MOCK_DECL(void, tor_gettimeofday, (struct timeval *timeval));
 
 #ifdef TOR_UNIT_TESTS
 void tor_sleep_msec(int msec);
diff --git a/src/common/util.c b/src/common/util.c
index b14b6f3979..53e4507f1f 100644
--- a/src/common/util.c
+++ b/src/common/util.c
@@ -1834,6 +1834,15 @@ format_iso_time(char *buf, time_t t)
   strftime(buf, ISO_TIME_LEN+1, "%Y-%m-%d %H:%M:%S", tor_gmtime_r(&t, &tm));
 }
 
+/** As format_local_iso_time, but use the yyyy-mm-ddThh:mm:ss format to avoid
+ * embedding an internal space. */
+void
+format_local_iso_time_nospace(char *buf, time_t t)
+{
+  format_local_iso_time(buf, t);
+  buf[10] = 'T';
+}
+
 /** As format_iso_time, but use the yyyy-mm-ddThh:mm:ss format to avoid
  * embedding an internal space. */
 void
diff --git a/src/common/util.h b/src/common/util.h
index c0d20e1b22..7172b7da08 100644
--- a/src/common/util.h
+++ b/src/common/util.h
@@ -271,6 +271,7 @@ int parse_rfc1123_time(const char *buf, time_t *t);
 #define ISO_TIME_USEC_LEN (ISO_TIME_LEN+7)
 void format_local_iso_time(char *buf, time_t t);
 void format_iso_time(char *buf, time_t t);
+void format_local_iso_time_nospace(char *buf, time_t t);
 void format_iso_time_nospace(char *buf, time_t t);
 void format_iso_time_nospace_usec(char *buf, const struct timeval *tv);
 int parse_iso_time_(const char *cp, time_t *t, int strict, int nospace);
diff --git a/src/or/control.c b/src/or/control.c
index 6f56313eaa..dda8872182 100644
--- a/src/or/control.c
+++ b/src/or/control.c
@@ -1931,6 +1931,31 @@ getinfo_helper_listeners(control_connection_t *control_conn,
   return 0;
 }
 
+/** Implementation helper for GETINFO: answers requests for information about
+ * the current time in both local and UTF forms. */
+STATIC int
+getinfo_helper_current_time(control_connection_t *control_conn,
+                         const char *question,
+                         char **answer, const char **errmsg)
+{
+  (void)control_conn;
+  (void)errmsg;
+
+  struct timeval now;
+  tor_gettimeofday(&now);
+  char timebuf[ISO_TIME_LEN+1];
+
+  if (!strcmp(question, "current-time/local"))
+    format_local_iso_time_nospace(timebuf, (time_t)now.tv_sec);
+  else if (!strcmp(question, "current-time/utc"))
+    format_iso_time_nospace(timebuf, (time_t)now.tv_sec);
+  else
+    return 0;
+
+  *answer = tor_strdup(timebuf);
+  return 0;
+}
+
 /** Implementation helper for GETINFO: knows the answers for questions about
  * directory information. */
 STATIC int
@@ -3073,6 +3098,9 @@ static const getinfo_item_t getinfo_items[] = {
   DOC("config/defaults",
       "List of default values for configuration options. "
       "See also config/names"),
+  PREFIX("current-time/", current_time, "Current time."),
+  DOC("current-time/local", "Current time on the local system."),
+  DOC("current-time/utc", "Current UTC time."),
   PREFIX("downloads/networkstatus/", downloads,
          "Download statuses for networkstatus objects"),
   DOC("downloads/networkstatus/ns",
diff --git a/src/or/control.h b/src/or/control.h
index 2fd3c553f3..2f312a6638 100644
--- a/src/or/control.h
+++ b/src/or/control.h
@@ -311,6 +311,10 @@ STATIC int getinfo_helper_dir(
     control_connection_t *control_conn,
     const char *question, char **answer,
     const char **errmsg);
+STATIC int getinfo_helper_current_time(
+    control_connection_t *control_conn,
+    const char *question, char **answer,
+    const char **errmsg);
 
 #endif /* defined(CONTROL_PRIVATE) */
 
diff --git a/src/test/test_controller.c b/src/test/test_controller.c
index 1c285bb3a2..3b58a78e1d 100644
--- a/src/test/test_controller.c
+++ b/src/test/test_controller.c
@@ -1470,6 +1470,61 @@ test_download_status_bridge(void *arg)
   return;
 }
 
+/** Set timeval to a mock date and time. This is neccessary
+ * to make tor_gettimeofday() mockable. */
+static void
+mock_tor_gettimeofday(struct timeval *timeval)
+{
+  timeval->tv_sec = 1523405073;
+  timeval->tv_usec = 271645;
+}
+
+static void
+test_current_time(void *arg)
+{
+  /* We just need one of these to pass, it doesn't matter what's in it */
+  control_connection_t dummy;
+  /* Get results out */
+  char *answer = NULL;
+  const char *errmsg = NULL;
+
+  (void)arg;
+
+  /* We need these for storing the (mock) time. */
+  MOCK(tor_gettimeofday, mock_tor_gettimeofday);
+  struct timeval now;
+  tor_gettimeofday(&now);
+  char timebuf[ISO_TIME_LEN+1];
+
+  /* Case 1 - local time */
+  format_local_iso_time_nospace(timebuf, (time_t)now.tv_sec);
+  getinfo_helper_current_time(&dummy,
+                              "current-time/local",
+                              &answer, &errmsg);
+  tt_ptr_op(answer, OP_NE, NULL);
+  tt_ptr_op(errmsg, OP_EQ, NULL);
+  tt_str_op(answer, OP_EQ, timebuf);
+  tor_free(answer);
+  errmsg = NULL;
+
+  /* Case 2 - UTC time */
+  format_iso_time_nospace(timebuf, (time_t)now.tv_sec);
+  getinfo_helper_current_time(&dummy,
+                              "current-time/utc",
+                              &answer, &errmsg);
+  tt_ptr_op(answer, OP_NE, NULL);
+  tt_ptr_op(errmsg, OP_EQ, NULL);
+  tt_str_op(answer, OP_EQ, timebuf);
+  tor_free(answer);
+  errmsg = NULL;
+
+ done:
+  UNMOCK(tor_gettimeofday);
+  tor_free(answer);
+
+  return;
+}
+
 struct testcase_t controller_tests[] = {
   { "add_onion_helper_keyarg_v2", test_add_onion_helper_keyarg_v2, 0,
     NULL, NULL },
@@ -1486,6 +1541,7 @@ struct testcase_t controller_tests[] = {
     NULL },
   { "download_status_desc", test_download_status_desc, 0, NULL, NULL },
   { "download_status_bridge", test_download_status_bridge, 0, NULL, NULL },
+  { "current_time", test_current_time, 0, NULL, NULL },
   END_OF_TESTCASES
 };