diff options
Diffstat (limited to 'otime.h')
| -rw-r--r-- | otime.h | 271 |
1 files changed, 271 insertions, 0 deletions
@@ -0,0 +1,271 @@ +/* + * 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 + */ + +#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); + +#ifdef WIN32 +int gettimeofday(struct timeval *tv, void *tz); +#endif + +/* 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 && defined(HAVE_GETTIMEOFDAY) + +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 && defined(HAVE_GETTIMEOFDAY)) */ + +static inline void +update_time (void) +{ +#if defined(WIN32) && defined(HAVE_GETTIMEOFDAY) + struct timeval tv; + if (!gettimeofday (&tv, NULL)) + { + if (tv.tv_sec != now) + now = tv.tv_sec; + } +#else + const time_t real_time = time (NULL); + if (real_time != now) + now = real_time; +#endif +} + +#ifdef HAVE_GETTIMEOFDAY + +static inline int +openvpn_gettimeofday (struct timeval *tv, void *tz) +{ + return gettimeofday (tv, tz); +} + +#endif + +#endif /* TIME_BACKTRACK_PROTECTION && defined(HAVE_GETTIMEOFDAY) */ + +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 |