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 #if defined(__MINGW32__)
63 #define MINGW_HAS_SECURE_API 1  /* supplied by libmingwex */
64 #include <sec_api/time_s.h>  /* for correct definition of gmtime_s */
65 #undef MINGW_HAS_SECURE_API
66 #endif
67 
68 #include <openssl/time_support.h>
69 
70 #include <time.h>
71 
72 
73 #define SECS_PER_DAY (24 * 60 * 60)
74 
OPENSSL_gmtime(const time_t * time,struct tm * result)75 struct tm *OPENSSL_gmtime(const time_t *time, struct tm *result) {
76 #if defined(OPENSSL_WINDOWS)
77   if (gmtime_s(result, time)) {
78     return NULL;
79   }
80   return result;
81 #else
82   return gmtime_r(time, result);
83 #endif
84 }
85 
86 /* Convert date to and from julian day Uses Fliegel & Van Flandern algorithm */
date_to_julian(int y,int m,int d)87 static long date_to_julian(int y, int m, int d) {
88   return (1461 * (y + 4800 + (m - 14) / 12)) / 4 +
89          (367 * (m - 2 - 12 * ((m - 14) / 12))) / 12 -
90          (3 * ((y + 4900 + (m - 14) / 12) / 100)) / 4 + d - 32075;
91 }
92 
julian_to_date(long jd,int * y,int * m,int * d)93 static void julian_to_date(long jd, int *y, int *m, int *d) {
94   long L = jd + 68569;
95   long n = (4 * L) / 146097;
96   long i, j;
97 
98   L = L - (146097 * n + 3) / 4;
99   i = (4000 * (L + 1)) / 1461001;
100   L = L - (1461 * i) / 4 + 31;
101   j = (80 * L) / 2447;
102   *d = L - (2447 * j) / 80;
103   L = j / 11;
104   *m = j + 2 - (12 * L);
105   *y = 100 * (n - 49) + i + L;
106 }
107 
108 /* Convert tm structure and offset into julian day and seconds */
julian_adj(const struct tm * tm,int off_day,long offset_sec,long * pday,int * psec)109 static int julian_adj(const struct tm *tm, int off_day, long offset_sec,
110                       long *pday, int *psec) {
111   int offset_hms, offset_day;
112   long time_jd;
113   int time_year, time_month, time_day;
114   /* split offset into days and day seconds */
115   offset_day = offset_sec / SECS_PER_DAY;
116   /* Avoid sign issues with % operator */
117   offset_hms = offset_sec - (offset_day * SECS_PER_DAY);
118   offset_day += off_day;
119   /* Add current time seconds to offset */
120   offset_hms += tm->tm_hour * 3600 + tm->tm_min * 60 + tm->tm_sec;
121   /* Adjust day seconds if overflow */
122   if (offset_hms >= SECS_PER_DAY) {
123     offset_day++;
124     offset_hms -= SECS_PER_DAY;
125   } else if (offset_hms < 0) {
126     offset_day--;
127     offset_hms += SECS_PER_DAY;
128   }
129 
130   /* Convert date of time structure into a Julian day number. */
131 
132   time_year = tm->tm_year + 1900;
133   time_month = tm->tm_mon + 1;
134   time_day = tm->tm_mday;
135 
136   time_jd = date_to_julian(time_year, time_month, time_day);
137 
138   /* Work out Julian day of new date */
139   time_jd += offset_day;
140 
141   if (time_jd < 0) {
142     return 0;
143   }
144 
145   *pday = time_jd;
146   *psec = offset_hms;
147   return 1;
148 }
149 
OPENSSL_gmtime_adj(struct tm * tm,int off_day,long offset_sec)150 int OPENSSL_gmtime_adj(struct tm *tm, int off_day, long offset_sec) {
151   int time_sec, time_year, time_month, time_day;
152   long time_jd;
153 
154   /* Convert time and offset into julian day and seconds */
155   if (!julian_adj(tm, off_day, offset_sec, &time_jd, &time_sec)) {
156     return 0;
157   }
158 
159   /* Convert Julian day back to date */
160 
161   julian_to_date(time_jd, &time_year, &time_month, &time_day);
162 
163   if (time_year < 1900 || time_year > 9999) {
164     return 0;
165   }
166 
167   /* Update tm structure */
168 
169   tm->tm_year = time_year - 1900;
170   tm->tm_mon = time_month - 1;
171   tm->tm_mday = time_day;
172 
173   tm->tm_hour = time_sec / 3600;
174   tm->tm_min = (time_sec / 60) % 60;
175   tm->tm_sec = time_sec % 60;
176 
177   return 1;
178 }
179 
OPENSSL_gmtime_diff(int * pday,int * psec,const struct tm * from,const struct tm * to)180 int OPENSSL_gmtime_diff(int *pday, int *psec, const struct tm *from,
181                         const struct tm *to) {
182   int from_sec, to_sec, diff_sec;
183   long from_jd, to_jd, diff_day;
184 
185   if (!julian_adj(from, 0, 0, &from_jd, &from_sec)) {
186     return 0;
187   }
188   if (!julian_adj(to, 0, 0, &to_jd, &to_sec)) {
189     return 0;
190   }
191 
192   diff_day = to_jd - from_jd;
193   diff_sec = to_sec - from_sec;
194   /* Adjust differences so both positive or both negative */
195   if (diff_day > 0 && diff_sec < 0) {
196     diff_day--;
197     diff_sec += SECS_PER_DAY;
198   }
199   if (diff_day < 0 && diff_sec > 0) {
200     diff_day++;
201     diff_sec -= SECS_PER_DAY;
202   }
203 
204   if (pday) {
205     *pday = (int)diff_day;
206   }
207   if (psec) {
208     *psec = diff_sec;
209   }
210 
211   return 1;
212 }
213