diff options
Diffstat (limited to 'lib/dns/time.c')
| -rw-r--r-- | lib/dns/time.c | 216 |
1 files changed, 216 insertions, 0 deletions
diff --git a/lib/dns/time.c b/lib/dns/time.c new file mode 100644 index 0000000..d110ace --- /dev/null +++ b/lib/dns/time.c @@ -0,0 +1,216 @@ +/* + * Copyright (C) Internet Systems Consortium, Inc. ("ISC") + * + * SPDX-License-Identifier: MPL-2.0 + * + * This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, you can obtain one at https://mozilla.org/MPL/2.0/. + * + * See the COPYRIGHT file distributed with this work for additional + * information regarding copyright ownership. + */ + +/*! \file */ + +#include <ctype.h> +#include <inttypes.h> +#include <stdio.h> +#include <time.h> + +#include <isc/print.h> +#include <isc/region.h> +#include <isc/result.h> +#include <isc/serial.h> +#include <isc/stdtime.h> +#include <isc/string.h> /* Required for HP/UX (and others?) */ +#include <isc/util.h> + +#include <dns/time.h> + +static const int days[12] = { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 }; + +isc_result_t +dns_time64_totext(int64_t t, isc_buffer_t *target) { + struct tm tm; + char buf[sizeof("!!!!!!YYYY!!!!!!!!MM!!!!!!!!DD!!!!!!!!HH!!!!!!!!MM!!!!" + "!!!!SS")]; + int secs; + unsigned int l; + isc_region_t region; + +/* + * Warning. Do NOT use arguments with side effects with these macros. + */ +#define is_leap(y) ((((y) % 4) == 0 && ((y) % 100) != 0) || ((y) % 400) == 0) +#define year_secs(y) ((is_leap(y) ? 366 : 365) * 86400) +#define month_secs(m, y) ((days[m] + ((m == 1 && is_leap(y)) ? 1 : 0)) * 86400) + + tm.tm_year = 70; + while (t < 0) { + if (tm.tm_year == 0) { + return (ISC_R_RANGE); + } + tm.tm_year--; + secs = year_secs(tm.tm_year + 1900); + t += secs; + } + while ((secs = year_secs(tm.tm_year + 1900)) <= t) { + t -= secs; + tm.tm_year++; + if (tm.tm_year + 1900 > 9999) { + return (ISC_R_RANGE); + } + } + tm.tm_mon = 0; + while ((secs = month_secs(tm.tm_mon, tm.tm_year + 1900)) <= t) { + t -= secs; + tm.tm_mon++; + } + tm.tm_mday = 1; + while (86400 <= t) { + t -= 86400; + tm.tm_mday++; + } + tm.tm_hour = 0; + while (3600 <= t) { + t -= 3600; + tm.tm_hour++; + } + tm.tm_min = 0; + while (60 <= t) { + t -= 60; + tm.tm_min++; + } + tm.tm_sec = (int)t; + /* yyyy mm dd HH MM SS */ + snprintf(buf, sizeof(buf), "%04d%02d%02d%02d%02d%02d", + tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday, tm.tm_hour, + tm.tm_min, tm.tm_sec); + + isc_buffer_availableregion(target, ®ion); + l = strlen(buf); + + if (l > region.length) { + return (ISC_R_NOSPACE); + } + + memmove(region.base, buf, l); + isc_buffer_add(target, l); + return (ISC_R_SUCCESS); +} + +int64_t +dns_time64_from32(uint32_t value) { + isc_stdtime_t now; + int64_t start; + int64_t t; + + /* + * Adjust the time to the closest epoch. This should be changed + * to use a 64-bit counterpart to isc_stdtime_get() if one ever + * is defined, but even the current code is good until the year + * 2106. + */ + isc_stdtime_get(&now); + start = (int64_t)now; + if (isc_serial_gt(value, now)) { + t = start + (value - now); + } else { + t = start - (now - value); + } + + return (t); +} + +isc_result_t +dns_time32_totext(uint32_t value, isc_buffer_t *target) { + return (dns_time64_totext(dns_time64_from32(value), target)); +} + +isc_result_t +dns_time64_fromtext(const char *source, int64_t *target) { + int year, month, day, hour, minute, second; + int64_t value; + int secs; + int i; + +#define RANGE(min, max, value) \ + do { \ + if (value < (min) || value > (max)) \ + return ((ISC_R_RANGE)); \ + } while (0) + + if (strlen(source) != 14U) { + return (DNS_R_SYNTAX); + } + /* + * Confirm the source only consists digits. sscanf() allows some + * minor exceptions. + */ + for (i = 0; i < 14; i++) { + if (!isdigit((unsigned char)source[i])) { + return (DNS_R_SYNTAX); + } + } + if (sscanf(source, "%4d%2d%2d%2d%2d%2d", &year, &month, &day, &hour, + &minute, &second) != 6) + { + return (DNS_R_SYNTAX); + } + + RANGE(0, 9999, year); + RANGE(1, 12, month); + RANGE(1, days[month - 1] + ((month == 2 && is_leap(year)) ? 1 : 0), + day); +#ifdef __COVERITY__ + /* + * Use a simplified range to silence Coverity warning (in + * arithmetic with day below). + */ + RANGE(1, 31, day); +#endif /* __COVERITY__ */ + + RANGE(0, 23, hour); + RANGE(0, 59, minute); + RANGE(0, 60, second); /* 60 == leap second. */ + + /* + * Calculate seconds from epoch. + * Note: this uses a idealized calendar. + */ + value = second + (60 * minute) + (3600 * hour) + ((day - 1) * 86400); + for (i = 0; i < (month - 1); i++) { + value += days[i] * 86400; + } + if (is_leap(year) && month > 2) { + value += 86400; + } + if (year < 1970) { + for (i = 1969; i >= year; i--) { + secs = (is_leap(i) ? 366 : 365) * 86400; + value -= secs; + } + } else { + for (i = 1970; i < year; i++) { + secs = (is_leap(i) ? 366 : 365) * 86400; + value += secs; + } + } + + *target = value; + return (ISC_R_SUCCESS); +} + +isc_result_t +dns_time32_fromtext(const char *source, uint32_t *target) { + int64_t value64; + isc_result_t result; + result = dns_time64_fromtext(source, &value64); + if (result != ISC_R_SUCCESS) { + return (result); + } + *target = (uint32_t)value64; + + return (ISC_R_SUCCESS); +} |