1 /*
2 * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
3 *
4 * This Source Code Form is subject to the terms of the Mozilla Public
5 * License, v. 2.0. If a copy of the MPL was not distributed with this
6 * file, you can obtain one at https://mozilla.org/MPL/2.0/.
7 *
8 * See the COPYRIGHT file distributed with this work for additional
9 * information regarding copyright ownership.
10 */
11
12 /*! \file */
13
14 #include <ctype.h>
15 #include <inttypes.h>
16 #include <stdio.h>
17 #include <time.h>
18
19 #include <isc/print.h>
20 #include <isc/region.h>
21 #include <isc/result.h>
22 #include <isc/serial.h>
23 #include <isc/stdtime.h>
24 #include <isc/string.h> /* Required for HP/UX (and others?) */
25 #include <isc/util.h>
26
27 #include <dns/time.h>
28
29 static const int days[12] = { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
30
31 isc_result_t
dns_time64_totext(int64_t t,isc_buffer_t * target)32 dns_time64_totext(int64_t t, isc_buffer_t *target) {
33 struct tm tm;
34 char buf[sizeof("!!!!!!YYYY!!!!!!!!MM!!!!!!!!DD!!!!!!!!HH!!!!!!!!MM!!!!"
35 "!!!!SS")];
36 int secs;
37 unsigned int l;
38 isc_region_t region;
39
40 /*
41 * Warning. Do NOT use arguments with side effects with these macros.
42 */
43 #define is_leap(y) ((((y) % 4) == 0 && ((y) % 100) != 0) || ((y) % 400) == 0)
44 #define year_secs(y) ((is_leap(y) ? 366 : 365) * 86400)
45 #define month_secs(m, y) ((days[m] + ((m == 1 && is_leap(y)) ? 1 : 0)) * 86400)
46
47 tm.tm_year = 70;
48 while (t < 0) {
49 if (tm.tm_year == 0) {
50 return (ISC_R_RANGE);
51 }
52 tm.tm_year--;
53 secs = year_secs(tm.tm_year + 1900);
54 t += secs;
55 }
56 while ((secs = year_secs(tm.tm_year + 1900)) <= t) {
57 t -= secs;
58 tm.tm_year++;
59 if (tm.tm_year + 1900 > 9999) {
60 return (ISC_R_RANGE);
61 }
62 }
63 tm.tm_mon = 0;
64 while ((secs = month_secs(tm.tm_mon, tm.tm_year + 1900)) <= t) {
65 t -= secs;
66 tm.tm_mon++;
67 }
68 tm.tm_mday = 1;
69 while (86400 <= t) {
70 t -= 86400;
71 tm.tm_mday++;
72 }
73 tm.tm_hour = 0;
74 while (3600 <= t) {
75 t -= 3600;
76 tm.tm_hour++;
77 }
78 tm.tm_min = 0;
79 while (60 <= t) {
80 t -= 60;
81 tm.tm_min++;
82 }
83 tm.tm_sec = (int)t;
84 /* yyyy mm dd HH MM SS */
85 snprintf(buf, sizeof(buf), "%04d%02d%02d%02d%02d%02d",
86 tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday, tm.tm_hour,
87 tm.tm_min, tm.tm_sec);
88
89 isc_buffer_availableregion(target, ®ion);
90 l = strlen(buf);
91
92 if (l > region.length) {
93 return (ISC_R_NOSPACE);
94 }
95
96 memmove(region.base, buf, l);
97 isc_buffer_add(target, l);
98 return (ISC_R_SUCCESS);
99 }
100
101 int64_t
dns_time64_from32(uint32_t value)102 dns_time64_from32(uint32_t value) {
103 isc_stdtime_t now;
104 int64_t start;
105 int64_t t;
106
107 /*
108 * Adjust the time to the closest epoch. This should be changed
109 * to use a 64-bit counterpart to isc_stdtime_get() if one ever
110 * is defined, but even the current code is good until the year
111 * 2106.
112 */
113 isc_stdtime_get(&now);
114 start = (int64_t)now;
115 if (isc_serial_gt(value, now)) {
116 t = start + (value - now);
117 } else {
118 t = start - (now - value);
119 }
120
121 return (t);
122 }
123
124 isc_result_t
dns_time32_totext(uint32_t value,isc_buffer_t * target)125 dns_time32_totext(uint32_t value, isc_buffer_t *target) {
126 return (dns_time64_totext(dns_time64_from32(value), target));
127 }
128
129 isc_result_t
dns_time64_fromtext(const char * source,int64_t * target)130 dns_time64_fromtext(const char *source, int64_t *target) {
131 int year, month, day, hour, minute, second;
132 int64_t value;
133 int secs;
134 int i;
135
136 #define RANGE(min, max, value) \
137 do { \
138 if (value < (min) || value > (max)) \
139 return ((ISC_R_RANGE)); \
140 } while (0)
141
142 if (strlen(source) != 14U) {
143 return (DNS_R_SYNTAX);
144 }
145 /*
146 * Confirm the source only consists digits. sscanf() allows some
147 * minor exceptions.
148 */
149 for (i = 0; i < 14; i++) {
150 if (!isdigit((unsigned char)source[i])) {
151 return (DNS_R_SYNTAX);
152 }
153 }
154 if (sscanf(source, "%4d%2d%2d%2d%2d%2d", &year, &month, &day, &hour,
155 &minute, &second) != 6)
156 {
157 return (DNS_R_SYNTAX);
158 }
159
160 RANGE(0, 9999, year);
161 RANGE(1, 12, month);
162 RANGE(1, days[month - 1] + ((month == 2 && is_leap(year)) ? 1 : 0),
163 day);
164 #ifdef __COVERITY__
165 /*
166 * Use a simplified range to silence Coverity warning (in
167 * arithmetic with day below).
168 */
169 RANGE(1, 31, day);
170 #endif /* __COVERITY__ */
171
172 RANGE(0, 23, hour);
173 RANGE(0, 59, minute);
174 RANGE(0, 60, second); /* 60 == leap second. */
175
176 /*
177 * Calculate seconds from epoch.
178 * Note: this uses a idealized calendar.
179 */
180 value = second + (60 * minute) + (3600 * hour) + ((day - 1) * 86400);
181 for (i = 0; i < (month - 1); i++) {
182 value += days[i] * 86400;
183 }
184 if (is_leap(year) && month > 2) {
185 value += 86400;
186 }
187 if (year < 1970) {
188 for (i = 1969; i >= year; i--) {
189 secs = (is_leap(i) ? 366 : 365) * 86400;
190 value -= secs;
191 }
192 } else {
193 for (i = 1970; i < year; i++) {
194 secs = (is_leap(i) ? 366 : 365) * 86400;
195 value += secs;
196 }
197 }
198
199 *target = value;
200 return (ISC_R_SUCCESS);
201 }
202
203 isc_result_t
dns_time32_fromtext(const char * source,uint32_t * target)204 dns_time32_fromtext(const char *source, uint32_t *target) {
205 int64_t value64;
206 isc_result_t result;
207 result = dns_time64_fromtext(source, &value64);
208 if (result != ISC_R_SUCCESS) {
209 return (result);
210 }
211 *target = (uint32_t)value64;
212
213 return (ISC_R_SUCCESS);
214 }
215