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-rw-r--r--lib/dns/time.c216
1 files changed, 216 insertions, 0 deletions
diff --git a/lib/dns/time.c b/lib/dns/time.c
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+++ b/lib/dns/time.c
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+/*
+ * 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, &region);
+ 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);
+}