/*
* 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) 2002-2018 OpenVPN 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; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#ifndef OTIME_H
#define OTIME_H
#include "common.h"
#include "integer.h"
#include "buffer.h"
struct frequency_limit
{
int max;
int per;
int n;
time_t reset;
};
struct frequency_limit *frequency_limit_init(int max, int per);
void frequency_limit_free(struct frequency_limit *f);
bool frequency_limit_event_allowed(struct frequency_limit *f);
/* 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 timeval functions */
const char *tv_string(const struct timeval *tv, struct gc_arena *gc);
const char *tv_string_abs(const struct timeval *tv, struct gc_arena *gc);
extern time_t now; /* updated frequently to time(NULL) */
void time_test(void);
#if TIME_BACKTRACK_PROTECTION
void update_now(const time_t system_time);
extern time_t now_usec;
void update_now_usec(struct timeval *tv);
static inline int
openvpn_gettimeofday(struct timeval *tv, void *tz)
{
const int status = gettimeofday(tv, tz);
if (!status)
{
update_now_usec(tv);
tv->tv_sec = now;
tv->tv_usec = now_usec;
}
return status;
}
static inline void
update_time(void)
{
#ifdef _WIN32
/* on _WIN32, gettimeofday is faster than time(NULL) */
struct timeval tv;
openvpn_gettimeofday(&tv, NULL);
#else
update_now(time(NULL));
#endif
}
#else /* !TIME_BACKTRACK_PROTECTION */
static inline void
update_time(void)
{
#if defined(_WIN32)
/* on _WIN32, gettimeofday is faster than time(NULL) */
struct timeval tv;
if (!gettimeofday(&tv, NULL))
{
if (tv.tv_sec != now)
{
now = tv.tv_sec;
}
}
#else /* if defined(_WIN32) */
const time_t real_time = time(NULL);
if (real_time != now)
{
now = real_time;
}
#endif
}
static inline int
openvpn_gettimeofday(struct timeval *tv, void *tz)
{
return gettimeofday(tv, tz);
}
#endif /* TIME_BACKTRACK_PROTECTION */
static inline time_t
openvpn_time(time_t *t)
{
update_time();
if (t)
{
*t = now;
}
return now;
}
static inline void
tv_clear(struct timeval *tv)
{
tv->tv_sec = 0;
tv->tv_usec = 0;
}
static inline bool
tv_defined(const struct timeval *tv)
{
return tv->tv_sec > 0 && tv->tv_usec > 0;
}
/* return tv1 - tv2 in usec, constrained by max_seconds */
static inline int
tv_subtract(const struct timeval *tv1, const struct timeval *tv2, const unsigned int max_seconds)
{
const int max_usec = max_seconds * 1000000;
const int sec_diff = tv1->tv_sec - tv2->tv_sec;
if (sec_diff > ((int)max_seconds + 10))
{
return max_usec;
}
else if (sec_diff < -((int)max_seconds + 10))
{
return -max_usec;
}
return constrain_int(sec_diff * 1000000 + (tv1->tv_usec - tv2->tv_usec), -max_usec, max_usec);
}
static inline void
tv_add(struct timeval *dest, const struct timeval *src)
{
dest->tv_sec += src->tv_sec;
dest->tv_usec += src->tv_usec;
dest->tv_sec += (dest->tv_usec >> 20);
dest->tv_usec &= 0x000FFFFF;
if (dest->tv_usec >= 1000000)
{
dest->tv_usec -= 1000000;
dest->tv_sec += 1;
}
}
static inline bool
tv_lt(const struct timeval *t1, const struct timeval *t2)
{
if (t1->tv_sec < t2->tv_sec)
{
return true;
}
else if (t1->tv_sec > t2->tv_sec)
{
return false;
}
else
{
return t1->tv_usec < t2->tv_usec;
}
}
static inline bool
tv_le(const struct timeval *t1, const struct timeval *t2)
{
if (t1->tv_sec < t2->tv_sec)
{
return true;
}
else if (t1->tv_sec > t2->tv_sec)
{
return false;
}
else
{
return t1->tv_usec <= t2->tv_usec;
}
}
static inline bool
tv_ge(const struct timeval *t1, const struct timeval *t2)
{
if (t1->tv_sec > t2->tv_sec)
{
return true;
}
else if (t1->tv_sec < t2->tv_sec)
{
return false;
}
else
{
return t1->tv_usec >= t2->tv_usec;
}
}
static inline bool
tv_gt(const struct timeval *t1, const struct timeval *t2)
{
if (t1->tv_sec > t2->tv_sec)
{
return true;
}
else if (t1->tv_sec < t2->tv_sec)
{
return false;
}
else
{
return t1->tv_usec > t2->tv_usec;
}
}
static inline bool
tv_eq(const struct timeval *t1, const struct timeval *t2)
{
return t1->tv_sec == t2->tv_sec && t1->tv_usec == t2->tv_usec;
}
static inline void
tv_delta(struct timeval *dest, const struct timeval *t1, const struct timeval *t2)
{
int sec = t2->tv_sec - t1->tv_sec;
int usec = t2->tv_usec - t1->tv_usec;
while (usec < 0)
{
usec += 1000000;
sec -= 1;
}
if (sec < 0)
{
usec = sec = 0;
}
dest->tv_sec = sec;
dest->tv_usec = usec;
}
#define TV_WITHIN_SIGMA_MAX_SEC 600
#define TV_WITHIN_SIGMA_MAX_USEC (TV_WITHIN_SIGMA_MAX_SEC * 1000000)
/*
* Is t1 and t2 within sigma microseconds of each other?
*/
static inline bool
tv_within_sigma(const struct timeval *t1, const struct timeval *t2, unsigned int sigma)
{
const int delta = tv_subtract(t1, t2, TV_WITHIN_SIGMA_MAX_SEC); /* sigma should be less than 10 minutes */
return -(int)sigma <= delta && delta <= (int)sigma;
}
/*
* Used to determine in how many seconds we should be
* called again.
*/
static inline void
interval_earliest_wakeup(interval_t *wakeup, time_t at, time_t current)
{
if (at > current)
{
const interval_t delta = (interval_t) (at - current);
if (delta < *wakeup)
{
*wakeup = delta;
}
if (*wakeup < 0)
{
*wakeup = 0;
}
}
}
#endif /* ifndef OTIME_H */