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authorParménides GV <parmegv@sdf.org>2014-04-09 16:03:55 +0200
committerParménides GV <parmegv@sdf.org>2014-04-09 16:07:34 +0200
commit1684c8f398922065a97e7da4dac4ac6a33cc5218 (patch)
tree76a4b11ae0d7b217c088f3c2b8fc7e69a7b8ae0d /app/openvpn/src/openvpn/otime.c
parentb9a2b085a8f508cd09e2639c70be845c992c4a3e (diff)
Back to the standard "app" module.
This return to "app" instead of "bitmask_android" is due to this reading: https://developer.android.com/sdk/installing/studio-build.html#projectStructure I'll have to tweak the final apk name in build.gradle.
Diffstat (limited to 'app/openvpn/src/openvpn/otime.c')
-rw-r--r--app/openvpn/src/openvpn/otime.c201
1 files changed, 201 insertions, 0 deletions
diff --git a/app/openvpn/src/openvpn/otime.c b/app/openvpn/src/openvpn/otime.c
new file mode 100644
index 00000000..2c1e5b13
--- /dev/null
+++ b/app/openvpn/src/openvpn/otime.c
@@ -0,0 +1,201 @@
+/*
+ * OpenVPN -- An application to securely tunnel IP networks
+ * over a single TCP/UDP port, with support for SSL/TLS-based
+ * session authentication and key exchange,
+ * packet encryption, packet authentication, and
+ * packet compression.
+ *
+ * Copyright (C) 2002-2010 OpenVPN Technologies, Inc. <sales@openvpn.net>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program (see the file COPYING included with this
+ * distribution); if not, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#elif defined(_MSC_VER)
+#include "config-msvc.h"
+#endif
+
+#include "syshead.h"
+
+#include "otime.h"
+
+#include "memdbg.h"
+
+time_t now = 0; /* GLOBAL */
+
+#if TIME_BACKTRACK_PROTECTION
+
+static time_t now_adj = 0; /* GLOBAL */
+time_t now_usec = 0; /* GLOBAL */
+
+/*
+ * Try to filter out time instability caused by the system
+ * clock backtracking or jumping forward.
+ */
+
+void
+update_now (const time_t system_time)
+{
+ const int forward_threshold = 86400; /* threshold at which to dampen forward jumps */
+ const int backward_trigger = 10; /* backward jump must be >= this many seconds before we adjust */
+ time_t real_time = system_time + now_adj;
+
+ if (real_time > now)
+ {
+ const time_t overshoot = real_time - now - 1;
+ if (overshoot > forward_threshold && now_adj >= overshoot)
+ {
+ now_adj -= overshoot;
+ real_time -= overshoot;
+ }
+ now = real_time;
+ }
+ else if (real_time < now - backward_trigger)
+ now_adj += (now - real_time);
+}
+
+void
+update_now_usec (struct timeval *tv)
+{
+ const time_t last = now;
+ update_now (tv->tv_sec);
+ if (now > last || (now == last && tv->tv_usec > now_usec))
+ now_usec = tv->tv_usec;
+}
+
+#endif /* TIME_BACKTRACK_PROTECTION */
+
+/*
+ * Return a numerical string describing a struct timeval.
+ */
+const char *
+tv_string (const struct timeval *tv, struct gc_arena *gc)
+{
+ struct buffer out = alloc_buf_gc (64, gc);
+ buf_printf (&out, "[%d/%d]",
+ (int) tv->tv_sec,
+ (int )tv->tv_usec);
+ return BSTR (&out);
+}
+
+/*
+ * Return an ascii string describing an absolute
+ * date/time in a struct timeval.
+ *
+ */
+const char *
+tv_string_abs (const struct timeval *tv, struct gc_arena *gc)
+{
+ return time_string ((time_t) tv->tv_sec,
+ (int) tv->tv_usec,
+ true,
+ gc);
+}
+
+/* format a time_t as ascii, or use current time if 0 */
+
+const char *
+time_string (time_t t, int usec, bool show_usec, struct gc_arena *gc)
+{
+ struct buffer out = alloc_buf_gc (64, gc);
+ struct timeval tv;
+
+ if (t)
+ {
+ tv.tv_sec = t;
+ tv.tv_usec = usec;
+ }
+ else
+ {
+ gettimeofday (&tv, NULL);
+ }
+
+ t = tv.tv_sec;
+ buf_printf (&out, "%s", ctime(&t));
+ buf_rmtail (&out, '\n');
+
+ if (show_usec && tv.tv_usec)
+ buf_printf (&out, " us=%d", (int)tv.tv_usec);
+
+ return BSTR (&out);
+}
+
+/*
+ * Limit the frequency of an event stream.
+ *
+ * Used to control maximum rate of new
+ * incoming connections.
+ */
+
+struct frequency_limit *
+frequency_limit_init (int max, int per)
+{
+ struct frequency_limit *f;
+
+ ASSERT (max >= 0 && per >= 0);
+
+ ALLOC_OBJ (f, struct frequency_limit);
+ f->max = max;
+ f->per = per;
+ f->n = 0;
+ f->reset = 0;
+ return f;
+}
+
+void
+frequency_limit_free (struct frequency_limit *f)
+{
+ free (f);
+}
+
+bool
+frequency_limit_event_allowed (struct frequency_limit *f)
+{
+ if (f->per)
+ {
+ bool ret;
+ if (now >= f->reset + f->per)
+ {
+ f->reset = now;
+ f->n = 0;
+ }
+ ret = (++f->n <= f->max);
+ return ret;
+ }
+ else
+ return true;
+}
+
+#ifdef TIME_TEST
+void
+time_test (void)
+{
+ struct timeval tv;
+ time_t t;
+ int i;
+ for (i = 0; i < 10000; ++i)
+ {
+ t = time(NULL);
+ gettimeofday (&tv, NULL);
+#if 1
+ msg (M_INFO, "t=%u s=%u us=%u",
+ (unsigned int)t,
+ (unsigned int)tv.tv_sec,
+ (unsigned int)tv.tv_usec);
+#endif
+ }
+}
+#endif