1/* Written by Richard Levitte (richard@levitte.org) for the OpenSSL
2 * project 2001.
3 * Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
4 * project 2008.
5 */
6/* ====================================================================
7 * Copyright (c) 2001 The OpenSSL Project.  All rights reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 *
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 *
16 * 2. Redistributions in binary form must reproduce the above copyright
17 *    notice, this list of conditions and the following disclaimer in
18 *    the documentation and/or other materials provided with the
19 *    distribution.
20 *
21 * 3. All advertising materials mentioning features or use of this
22 *    software must display the following acknowledgment:
23 *    "This product includes software developed by the OpenSSL Project
24 *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
25 *
26 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
27 *    endorse or promote products derived from this software without
28 *    prior written permission. For written permission, please contact
29 *    licensing@OpenSSL.org.
30 *
31 * 5. Products derived from this software may not be called "OpenSSL"
32 *    nor may "OpenSSL" appear in their names without prior written
33 *    permission of the OpenSSL Project.
34 *
35 * 6. Redistributions of any form whatsoever must retain the following
36 *    acknowledgment:
37 *    "This product includes software developed by the OpenSSL Project
38 *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
39 *
40 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
41 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
42 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
43 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
44 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
45 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
46 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
47 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
49 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
50 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
51 * OF THE POSSIBILITY OF SUCH DAMAGE.
52 * ====================================================================
53 *
54 * This product includes cryptographic software written by Eric Young
55 * (eay@cryptsoft.com).  This product includes software written by Tim
56 * Hudson (tjh@cryptsoft.com). */
57
58#if !defined(_POSIX_C_SOURCE)
59#define _POSIX_C_SOURCE 201410L  /* for gmtime_r */
60#endif
61
62#include "asn1_locl.h"
63
64#include <time.h>
65
66
67#define SECS_PER_DAY (24 * 60 * 60)
68
69struct tm *OPENSSL_gmtime(const time_t *time, struct tm *result) {
70#if defined(OPENSSL_WINDOWS)
71  if (gmtime_s(result, time)) {
72    return NULL;
73  }
74  return result;
75#else
76  return gmtime_r(time, result);
77#endif
78}
79
80/* Convert date to and from julian day Uses Fliegel & Van Flandern algorithm */
81static long date_to_julian(int y, int m, int d) {
82  return (1461 * (y + 4800 + (m - 14) / 12)) / 4 +
83         (367 * (m - 2 - 12 * ((m - 14) / 12))) / 12 -
84         (3 * ((y + 4900 + (m - 14) / 12) / 100)) / 4 + d - 32075;
85}
86
87static void julian_to_date(long jd, int *y, int *m, int *d) {
88  long L = jd + 68569;
89  long n = (4 * L) / 146097;
90  long i, j;
91
92  L = L - (146097 * n + 3) / 4;
93  i = (4000 * (L + 1)) / 1461001;
94  L = L - (1461 * i) / 4 + 31;
95  j = (80 * L) / 2447;
96  *d = L - (2447 * j) / 80;
97  L = j / 11;
98  *m = j + 2 - (12 * L);
99  *y = 100 * (n - 49) + i + L;
100}
101
102/* Convert tm structure and offset into julian day and seconds */
103static int julian_adj(const struct tm *tm, int off_day, long offset_sec,
104                      long *pday, int *psec) {
105  int offset_hms, offset_day;
106  long time_jd;
107  int time_year, time_month, time_day;
108  /* split offset into days and day seconds */
109  offset_day = offset_sec / SECS_PER_DAY;
110  /* Avoid sign issues with % operator */
111  offset_hms = offset_sec - (offset_day * SECS_PER_DAY);
112  offset_day += off_day;
113  /* Add current time seconds to offset */
114  offset_hms += tm->tm_hour * 3600 + tm->tm_min * 60 + tm->tm_sec;
115  /* Adjust day seconds if overflow */
116  if (offset_hms >= SECS_PER_DAY) {
117    offset_day++;
118    offset_hms -= SECS_PER_DAY;
119  } else if (offset_hms < 0) {
120    offset_day--;
121    offset_hms += SECS_PER_DAY;
122  }
123
124  /* Convert date of time structure into a Julian day number. */
125
126  time_year = tm->tm_year + 1900;
127  time_month = tm->tm_mon + 1;
128  time_day = tm->tm_mday;
129
130  time_jd = date_to_julian(time_year, time_month, time_day);
131
132  /* Work out Julian day of new date */
133  time_jd += offset_day;
134
135  if (time_jd < 0) {
136    return 0;
137  }
138
139  *pday = time_jd;
140  *psec = offset_hms;
141  return 1;
142}
143
144int OPENSSL_gmtime_adj(struct tm *tm, int off_day, long offset_sec) {
145  int time_sec, time_year, time_month, time_day;
146  long time_jd;
147
148  /* Convert time and offset into julian day and seconds */
149  if (!julian_adj(tm, off_day, offset_sec, &time_jd, &time_sec)) {
150    return 0;
151  }
152
153  /* Convert Julian day back to date */
154
155  julian_to_date(time_jd, &time_year, &time_month, &time_day);
156
157  if (time_year < 1900 || time_year > 9999) {
158    return 0;
159  }
160
161  /* Update tm structure */
162
163  tm->tm_year = time_year - 1900;
164  tm->tm_mon = time_month - 1;
165  tm->tm_mday = time_day;
166
167  tm->tm_hour = time_sec / 3600;
168  tm->tm_min = (time_sec / 60) % 60;
169  tm->tm_sec = time_sec % 60;
170
171  return 1;
172}
173
174int OPENSSL_gmtime_diff(int *out_days, int *out_secs, const struct tm *from,
175                        const struct tm *to) {
176  int from_sec, to_sec, diff_sec;
177  long from_jd, to_jd, diff_day;
178
179  if (!julian_adj(from, 0, 0, &from_jd, &from_sec)) {
180    return 0;
181  }
182  if (!julian_adj(to, 0, 0, &to_jd, &to_sec)) {
183    return 0;
184  }
185
186  diff_day = to_jd - from_jd;
187  diff_sec = to_sec - from_sec;
188  /* Adjust differences so both positive or both negative */
189  if (diff_day > 0 && diff_sec < 0) {
190    diff_day--;
191    diff_sec += SECS_PER_DAY;
192  }
193  if (diff_day < 0 && diff_sec > 0) {
194    diff_day++;
195    diff_sec -= SECS_PER_DAY;
196  }
197
198  if (out_days) {
199    *out_days = (int)diff_day;
200  }
201  if (out_secs) {
202    *out_secs = diff_sec;
203  }
204
205  return 1;
206}
207