diff options
Diffstat (limited to 'lib/dns/ttl.c')
| -rw-r--r-- | lib/dns/ttl.c | 225 |
1 files changed, 225 insertions, 0 deletions
diff --git a/lib/dns/ttl.c b/lib/dns/ttl.c new file mode 100644 index 0000000..9c6a8ae --- /dev/null +++ b/lib/dns/ttl.c @@ -0,0 +1,225 @@ +/* + * 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 <errno.h> +#include <inttypes.h> +#include <stdbool.h> +#include <stdio.h> +#include <stdlib.h> + +#include <isc/buffer.h> +#include <isc/parseint.h> +#include <isc/print.h> +#include <isc/region.h> +#include <isc/result.h> +#include <isc/string.h> +#include <isc/util.h> + +#include <dns/ttl.h> + +#define RETERR(x) \ + do { \ + isc_result_t _r = (x); \ + if (_r != ISC_R_SUCCESS) \ + return ((_r)); \ + } while (0) + +static isc_result_t +bind_ttl(isc_textregion_t *source, uint32_t *ttl); + +/* + * Helper for dns_ttl_totext(). + */ +static isc_result_t +ttlfmt(unsigned int t, const char *s, bool verbose, bool space, + isc_buffer_t *target) { + char tmp[60]; + unsigned int len; + isc_region_t region; + + if (verbose) { + len = snprintf(tmp, sizeof(tmp), "%s%u %s%s", space ? " " : "", + t, s, t == 1 ? "" : "s"); + } else { + len = snprintf(tmp, sizeof(tmp), "%u%c", t, s[0]); + } + + INSIST(len + 1 <= sizeof(tmp)); + isc_buffer_availableregion(target, ®ion); + if (len > region.length) { + return (ISC_R_NOSPACE); + } + memmove(region.base, tmp, len); + isc_buffer_add(target, len); + + return (ISC_R_SUCCESS); +} + +/* + * Derived from bind8 ns_format_ttl(). + */ +isc_result_t +dns_ttl_totext(uint32_t src, bool verbose, bool upcase, isc_buffer_t *target) { + unsigned secs, mins, hours, days, weeks, x; + + secs = src % 60; + src /= 60; + mins = src % 60; + src /= 60; + hours = src % 24; + src /= 24; + days = src % 7; + src /= 7; + weeks = src; + src = 0; + POST(src); + + x = 0; + if (weeks != 0) { + RETERR(ttlfmt(weeks, "week", verbose, (x > 0), target)); + x++; + } + if (days != 0) { + RETERR(ttlfmt(days, "day", verbose, (x > 0), target)); + x++; + } + if (hours != 0) { + RETERR(ttlfmt(hours, "hour", verbose, (x > 0), target)); + x++; + } + if (mins != 0) { + RETERR(ttlfmt(mins, "minute", verbose, (x > 0), target)); + x++; + } + if (secs != 0 || (weeks == 0 && days == 0 && hours == 0 && mins == 0)) { + RETERR(ttlfmt(secs, "second", verbose, (x > 0), target)); + x++; + } + INSIST(x > 0); + /* + * If only a single unit letter is printed, print it + * in upper case. (Why? Because BIND 8 does that. + * Presumably it has a reason.) + */ + if (x == 1 && upcase && !verbose) { + isc_region_t region; + /* + * The unit letter is the last character in the + * used region of the buffer. + * + * toupper() does not need its argument to be masked of cast + * here because region.base is type unsigned char *. + */ + isc_buffer_usedregion(target, ®ion); + region.base[region.length - 1] = + toupper(region.base[region.length - 1]); + } + return (ISC_R_SUCCESS); +} + +isc_result_t +dns_counter_fromtext(isc_textregion_t *source, uint32_t *ttl) { + return (bind_ttl(source, ttl)); +} + +isc_result_t +dns_ttl_fromtext(isc_textregion_t *source, uint32_t *ttl) { + isc_result_t result; + + result = bind_ttl(source, ttl); + if (result != ISC_R_SUCCESS && result != ISC_R_RANGE) { + result = DNS_R_BADTTL; + } + return (result); +} + +static isc_result_t +bind_ttl(isc_textregion_t *source, uint32_t *ttl) { + uint64_t tmp = 0ULL; + uint32_t n; + char *s; + char buf[64]; + char nbuf[64]; /* Number buffer */ + + /* + * Copy the buffer as it may not be NULL terminated. + * No legal counter / ttl is longer that 63 characters. + */ + if (source->length > sizeof(buf) - 1) { + return (DNS_R_SYNTAX); + } + /* Copy source->length bytes and NUL terminate. */ + snprintf(buf, sizeof(buf), "%.*s", (int)source->length, source->base); + s = buf; + + do { + isc_result_t result; + + char *np = nbuf; + while (*s != '\0' && isdigit((unsigned char)*s)) { + *np++ = *s++; + } + *np++ = '\0'; + INSIST(np - nbuf <= (int)sizeof(nbuf)); + result = isc_parse_uint32(&n, nbuf, 10); + if (result != ISC_R_SUCCESS) { + return (DNS_R_SYNTAX); + } + switch (*s) { + case 'w': + case 'W': + tmp += (uint64_t)n * 7 * 24 * 3600; + s++; + break; + case 'd': + case 'D': + tmp += (uint64_t)n * 24 * 3600; + s++; + break; + case 'h': + case 'H': + tmp += (uint64_t)n * 3600; + s++; + break; + case 'm': + case 'M': + tmp += (uint64_t)n * 60; + s++; + break; + case 's': + case 'S': + tmp += (uint64_t)n; + s++; + break; + case '\0': + /* Plain number? */ + if (tmp != 0ULL) { + return (DNS_R_SYNTAX); + } + tmp = n; + break; + default: + return (DNS_R_SYNTAX); + } + } while (*s != '\0'); + + if (tmp > 0xffffffffULL) { + return (ISC_R_RANGE); + } + + *ttl = (uint32_t)(tmp & 0xffffffffUL); + return (ISC_R_SUCCESS); +} |