1/* $NetBSD: time.c,v 1.8 2024/02/21 22:52:08 christos Exp $ */ 2 3/* 4 * Copyright (C) Internet Systems Consortium, Inc. ("ISC") 5 * 6 * SPDX-License-Identifier: MPL-2.0 7 * 8 * This Source Code Form is subject to the terms of the Mozilla Public 9 * License, v. 2.0. If a copy of the MPL was not distributed with this 10 * file, you can obtain one at https://mozilla.org/MPL/2.0/. 11 * 12 * See the COPYRIGHT file distributed with this work for additional 13 * information regarding copyright ownership. 14 */ 15 16/*! \file */ 17 18#include <ctype.h> 19#include <inttypes.h> 20#include <stdio.h> 21#include <time.h> 22 23#include <isc/print.h> 24#include <isc/region.h> 25#include <isc/result.h> 26#include <isc/serial.h> 27#include <isc/stdtime.h> 28#include <isc/string.h> /* Required for HP/UX (and others?) */ 29#include <isc/util.h> 30 31#include <dns/time.h> 32 33static const int days[12] = { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 }; 34 35isc_result_t 36dns_time64_totext(int64_t t, isc_buffer_t *target) { 37 struct tm tm; 38 char buf[sizeof("!!!!!!YYYY!!!!!!!!MM!!!!!!!!DD!!!!!!!!HH!!!!!!!!MM!!!!" 39 "!!!!SS")]; 40 int secs; 41 unsigned int l; 42 isc_region_t region; 43 44/* 45 * Warning. Do NOT use arguments with side effects with these macros. 46 */ 47#define is_leap(y) ((((y) % 4) == 0 && ((y) % 100) != 0) || ((y) % 400) == 0) 48#define year_secs(y) ((is_leap(y) ? 366 : 365) * 86400) 49#define month_secs(m, y) ((days[m] + ((m == 1 && is_leap(y)) ? 1 : 0)) * 86400) 50 51 tm.tm_year = 70; 52 while (t < 0) { 53 if (tm.tm_year == 0) { 54 return (ISC_R_RANGE); 55 } 56 tm.tm_year--; 57 secs = year_secs(tm.tm_year + 1900); 58 t += secs; 59 } 60 while ((secs = year_secs(tm.tm_year + 1900)) <= t) { 61 t -= secs; 62 tm.tm_year++; 63 if (tm.tm_year + 1900 > 9999) { 64 return (ISC_R_RANGE); 65 } 66 } 67 tm.tm_mon = 0; 68 while ((secs = month_secs(tm.tm_mon, tm.tm_year + 1900)) <= t) { 69 t -= secs; 70 tm.tm_mon++; 71 } 72 tm.tm_mday = 1; 73 while (86400 <= t) { 74 t -= 86400; 75 tm.tm_mday++; 76 } 77 tm.tm_hour = 0; 78 while (3600 <= t) { 79 t -= 3600; 80 tm.tm_hour++; 81 } 82 tm.tm_min = 0; 83 while (60 <= t) { 84 t -= 60; 85 tm.tm_min++; 86 } 87 tm.tm_sec = (int)t; 88 /* yyyy mm dd HH MM SS */ 89 snprintf(buf, sizeof(buf), "%04d%02d%02d%02d%02d%02d", 90 tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday, tm.tm_hour, 91 tm.tm_min, tm.tm_sec); 92 93 isc_buffer_availableregion(target, ®ion); 94 l = strlen(buf); 95 96 if (l > region.length) { 97 return (ISC_R_NOSPACE); 98 } 99 100 memmove(region.base, buf, l); 101 isc_buffer_add(target, l); 102 return (ISC_R_SUCCESS); 103} 104 105int64_t 106dns_time64_from32(uint32_t value) { 107 isc_stdtime_t now; 108 int64_t start; 109 int64_t t; 110 111 /* 112 * Adjust the time to the closest epoch. This should be changed 113 * to use a 64-bit counterpart to isc_stdtime_get() if one ever 114 * is defined, but even the current code is good until the year 115 * 2106. 116 */ 117 isc_stdtime_get(&now); 118 start = (int64_t)now; 119 if (isc_serial_gt(value, now)) { 120 t = start + (value - now); 121 } else { 122 t = start - (now - value); 123 } 124 125 return (t); 126} 127 128isc_result_t 129dns_time32_totext(uint32_t value, isc_buffer_t *target) { 130 return (dns_time64_totext(dns_time64_from32(value), target)); 131} 132 133isc_result_t 134dns_time64_fromtext(const char *source, int64_t *target) { 135 int year, month, day, hour, minute, second; 136 int64_t value; 137 int secs; 138 int i; 139 140#define RANGE(min, max, value) \ 141 do { \ 142 if (value < (min) || value > (max)) \ 143 return ((ISC_R_RANGE)); \ 144 } while (0) 145 146 if (strlen(source) != 14U) { 147 return (DNS_R_SYNTAX); 148 } 149 /* 150 * Confirm the source only consists digits. sscanf() allows some 151 * minor exceptions. 152 */ 153 for (i = 0; i < 14; i++) { 154 if (!isdigit((unsigned char)source[i])) { 155 return (DNS_R_SYNTAX); 156 } 157 } 158 if (sscanf(source, "%4d%2d%2d%2d%2d%2d", &year, &month, &day, &hour, 159 &minute, &second) != 6) 160 { 161 return (DNS_R_SYNTAX); 162 } 163 164 RANGE(0, 9999, year); 165 RANGE(1, 12, month); 166 RANGE(1, days[month - 1] + ((month == 2 && is_leap(year)) ? 1 : 0), 167 day); 168#ifdef __COVERITY__ 169 /* 170 * Use a simplified range to silence Coverity warning (in 171 * arithmetic with day below). 172 */ 173 RANGE(1, 31, day); 174#endif /* __COVERITY__ */ 175 176 RANGE(0, 23, hour); 177 RANGE(0, 59, minute); 178 RANGE(0, 60, second); /* 60 == leap second. */ 179 180 /* 181 * Calculate seconds from epoch. 182 * Note: this uses a idealized calendar. 183 */ 184 value = second + (60 * minute) + (3600 * hour) + ((day - 1) * 86400); 185 for (i = 0; i < (month - 1); i++) { 186 value += days[i] * 86400; 187 } 188 if (is_leap(year) && month > 2) { 189 value += 86400; 190 } 191 if (year < 1970) { 192 for (i = 1969; i >= year; i--) { 193 secs = (is_leap(i) ? 366 : 365) * 86400; 194 value -= secs; 195 } 196 } else { 197 for (i = 1970; i < year; i++) { 198 secs = (is_leap(i) ? 366 : 365) * 86400; 199 value += secs; 200 } 201 } 202 203 *target = value; 204 return (ISC_R_SUCCESS); 205} 206 207isc_result_t 208dns_time32_fromtext(const char *source, uint32_t *target) { 209 int64_t value64; 210 isc_result_t result; 211 result = dns_time64_fromtext(source, &value64); 212 if (result != ISC_R_SUCCESS) { 213 return (result); 214 } 215 *target = (uint32_t)value64; 216 217 return (ISC_R_SUCCESS); 218} 219