C++ dns_rdata_reset函数代码示例

static isc_stdtime_t
setresign(dns_rdataset_t *modified) {
	dns_rdata_t rdata = DNS_RDATA_INIT;
	dns_rdata_rrsig_t sig;
	isc_stdtime_t when;
	isc_result_t result;

	result = dns_rdataset_first(modified);
	INSIST(result == ISC_R_SUCCESS);
	dns_rdataset_current(modified, &rdata);
	(void)dns_rdata_tostruct(&rdata, &sig, NULL);
	if ((rdata.flags & DNS_RDATA_OFFLINE) != 0)
		when = 0;
	else
		when = sig.timeexpire;
	dns_rdata_reset(&rdata);

	result = dns_rdataset_next(modified);
	while (result == ISC_R_SUCCESS) {
		dns_rdataset_current(modified, &rdata);
		(void)dns_rdata_tostruct(&rdata, &sig, NULL);
		if ((rdata.flags & DNS_RDATA_OFFLINE) != 0) {
			goto next_rr;
		}
		if (when == 0 || sig.timeexpire < when)
			when = sig.timeexpire;
 next_rr:
		dns_rdata_reset(&rdata);
		result = dns_rdataset_next(modified);
	}
	INSIST(result == ISC_R_NOMORE);
	return (when);
}

isc_result_t
dns_rdataset_additionaldata(dns_rdataset_t *rdataset,
			    dns_additionaldatafunc_t add, void *arg)
{
	dns_rdata_t rdata = DNS_RDATA_INIT;
	isc_result_t result;

	/*
	 * For each rdata in rdataset, call 'add' for each name and type in the
	 * rdata which is subject to additional section processing.
	 */

	REQUIRE(DNS_RDATASET_VALID(rdataset));
	REQUIRE((rdataset->attributes & DNS_RDATASETATTR_QUESTION) == 0);

	result = dns_rdataset_first(rdataset);
	if (result != ISC_R_SUCCESS)
		return (result);

	do {
		dns_rdataset_current(rdataset, &rdata);
		result = dns_rdata_additionaldata(&rdata, add, arg);
		if (result == ISC_R_SUCCESS)
			result = dns_rdataset_next(rdataset);
		dns_rdata_reset(&rdata);
	} while (result == ISC_R_SUCCESS);

	if (result != ISC_R_NOMORE)
		return (result);

	return (ISC_R_SUCCESS);
}

/*
 * Return true iff 'slab' (slab data of type 'type' and class 'rdclass')
 * contains an rdata identical to 'rdata'.  This does case insensitive
 * comparisons per DNSSEC.
 */
static inline isc_boolean_t
rdata_in_slab(unsigned char *slab, unsigned int reservelen,
	      dns_rdataclass_t rdclass, dns_rdatatype_t type,
	      dns_rdata_t *rdata)
{
	unsigned int count, i;
	unsigned char *current;
	dns_rdata_t trdata = DNS_RDATA_INIT;
	int n;

	current = slab + reservelen;
	count = *current++ * 256;
	count += *current++;

#if DNS_RDATASET_FIXED
	current += (4 * count);
#endif

	for (i = 0; i < count; i++) {
		rdata_from_slab(&current, rdclass, type, &trdata);

		n = dns_rdata_compare(&trdata, rdata);
		if (n == 0)
			return (ISC_TRUE);
		if (n > 0)	/* In DNSSEC order. */
			break;
		dns_rdata_reset(&trdata);
	}
	return (ISC_FALSE);
}

static isc_result_t
fill_array(int *pos, dns_rdataset_t *rdataset,
	   int size, unsigned char **rdatas, lwres_uint16_t *rdatalen)
{
	dns_rdata_t rdata;
	isc_result_t result;
	isc_region_t r;

	UNUSED(size);

	dns_rdata_init(&rdata);
	for (result = dns_rdataset_first(rdataset);
	     result == ISC_R_SUCCESS;
	     result = dns_rdataset_next(rdataset))
	{
		INSIST(*pos < size);
		dns_rdataset_current(rdataset, &rdata);
		dns_rdata_toregion(&rdata, &r);
		rdatas[*pos] = r.base;
		rdatalen[*pos] = r.length;
		dns_rdata_reset(&rdata);
		(*pos)++;
	}
	if (result == ISC_R_NOMORE)
		result = ISC_R_SUCCESS;
	return (result);
}

static void
db_rr_iterator_current(db_rr_iterator_t *it, dns_name_t **name,
		      isc_uint32_t *ttl, dns_rdata_t **rdata)
{
	REQUIRE(name != NULL && *name == NULL);
	REQUIRE(it->result == ISC_R_SUCCESS);
	*name = dns_fixedname_name(&it->fixedname);
	*ttl = it->rdataset.ttl;
	dns_rdata_reset(&it->rdata);
	dns_rdataset_current(&it->rdataset, &it->rdata);
	*rdata = &it->rdata;
}

static void
parse_rdata(isc_mem_t *mctx, char **cmdlinep, dns_rdataclass_t rdataclass,
	    dns_rdatatype_t rdatatype, dns_rdata_t *rdata)
{
	char *cmdline = *cmdlinep;
	isc_buffer_t source, *buf = NULL, *newbuf = NULL;
	isc_region_t r;
	isc_lex_t *lex = NULL;
	dns_rdatacallbacks_t callbacks;
	isc_result_t result;

	while (cmdline != NULL && *cmdline != 0 &&
	       isspace((unsigned char)*cmdline))
		cmdline++;

	if (cmdline != NULL && *cmdline != 0) {
		dns_rdatacallbacks_init(&callbacks);
		result = isc_lex_create(mctx, strlen(cmdline), &lex);
		check_result(result, "isc_lex_create");
		isc_buffer_init(&source, cmdline, strlen(cmdline));
		isc_buffer_add(&source, strlen(cmdline));
		result = isc_lex_openbuffer(lex, &source);
		check_result(result, "isc_lex_openbuffer");
		result = isc_buffer_allocate(mctx, &buf, MAXWIRE);
		check_result(result, "isc_buffer_allocate");
		result = dns_rdata_fromtext(rdata, rdataclass, rdatatype, lex,
					    dns_rootname, 0, mctx, buf,
					    &callbacks);
		isc_lex_destroy(&lex);
		if (result == ISC_R_SUCCESS) {
			isc_buffer_usedregion(buf, &r);
			result = isc_buffer_allocate(mctx, &newbuf, r.length);
			check_result(result, "isc_buffer_allocate");
			isc_buffer_putmem(newbuf, r.base, r.length);
			isc_buffer_usedregion(newbuf, &r);
			dns_rdata_reset(rdata);
			dns_rdata_fromregion(rdata, rdataclass, rdatatype, &r);
			isc_buffer_free(&buf);
			ISC_LIST_APPEND(usedbuffers, newbuf, link);
		} else {
			fprintf(stderr, "invalid rdata format: %s\n",
				isc_result_totext(result));
			isc_buffer_free(&buf);
			exit(1);
		}
	} else {
		rdata->flags = DNS_RDATA_UPDATE;
	}
	*cmdlinep = cmdline;
}

static isc_boolean_t
inrrset(dns_rdataset_t *rrset, dns_rdata_t *rdata) {
	isc_result_t result;
	dns_rdata_t current = DNS_RDATA_INIT;

	result = dns_rdataset_first(rrset);
	while (result == ISC_R_SUCCESS) {
		dns_rdataset_current(rrset, &current);
		if (dns_rdata_compare(rdata, &current) == 0)
			return (ISC_TRUE);
		dns_rdata_reset(&current);
		result = dns_rdataset_next(rrset);
	}
	return (ISC_FALSE);
}

/*%
 * short_form message print handler.  Calls above say_message()
 */
static isc_result_t
short_answer(dns_message_t *msg, dns_messagetextflag_t flags,
	     isc_buffer_t *buf, dig_query_t *query)
{
	dns_name_t *name;
	dns_rdataset_t *rdataset;
	isc_result_t result, loopresult;
	dns_name_t empty_name;
	dns_rdata_t rdata = DNS_RDATA_INIT;

	UNUSED(flags);

	dns_name_init(&empty_name, NULL);
	result = dns_message_firstname(msg, DNS_SECTION_ANSWER);
	if (result == ISC_R_NOMORE)
		return (ISC_R_SUCCESS);
	else if (result != ISC_R_SUCCESS)
		return (result);

	for (;;) {
		name = NULL;
		dns_message_currentname(msg, DNS_SECTION_ANSWER, &name);

		for (rdataset = ISC_LIST_HEAD(name->list);
		     rdataset != NULL;
		     rdataset = ISC_LIST_NEXT(rdataset, link)) {
			loopresult = dns_rdataset_first(rdataset);
			while (loopresult == ISC_R_SUCCESS) {
				dns_rdataset_current(rdataset, &rdata);
				result = say_message(&rdata, query,
						     buf);
				if (result == ISC_R_NOSPACE)
					return (result);
				check_result(result, "say_message");
				loopresult = dns_rdataset_next(rdataset);
				dns_rdata_reset(&rdata);
			}
		}
		result = dns_message_nextname(msg, DNS_SECTION_ANSWER);
		if (result == ISC_R_NOMORE)
			break;
		else if (result != ISC_R_SUCCESS)
			return (result);
	}

	return (ISC_R_SUCCESS);
}

static inline isc_result_t
copy_rdataset(dns_rdataset_t *rdataset, isc_buffer_t *buffer) {
	isc_result_t result;
	unsigned int count;
	isc_region_t ar, r;
	dns_rdata_t rdata = DNS_RDATA_INIT;

	/*
	 * Copy the rdataset count to the buffer.
	 */
	isc_buffer_availableregion(buffer, &ar);
	if (ar.length < 2)
		return (ISC_R_NOSPACE);
	count = dns_rdataset_count(rdataset);
	INSIST(count <= 65535);
	isc_buffer_putuint16(buffer, (isc_uint16_t)count);

	result = dns_rdataset_first(rdataset);
	while (result == ISC_R_SUCCESS) {
		dns_rdataset_current(rdataset, &rdata);
		dns_rdata_toregion(&rdata, &r);
		INSIST(r.length <= 65535);
		isc_buffer_availableregion(buffer, &ar);
		if (ar.length < 2)
			return (ISC_R_NOSPACE);
		/*
		 * Copy the rdata length to the buffer.
		 */
		isc_buffer_putuint16(buffer, (isc_uint16_t)r.length);
		/*
		 * Copy the rdata to the buffer.
		 */
		result = isc_buffer_copyregion(buffer, &r);
		if (result != ISC_R_SUCCESS)
			return (result);
		dns_rdata_reset(&rdata);
		result = dns_rdataset_next(rdataset);
	}
	if (result != ISC_R_NOMORE)
		return (result);

	return (ISC_R_SUCCESS);
}

void
dns_rriterator_current(dns_rriterator_t *it, dns_name_t **name,
		       isc_uint32_t *ttl, dns_rdataset_t **rdataset,
		       dns_rdata_t **rdata)
{
	REQUIRE(name != NULL && *name == NULL);
	REQUIRE(VALID_RRITERATOR(it));
	REQUIRE(it->result == ISC_R_SUCCESS);
	REQUIRE(rdataset == NULL || *rdataset == NULL);
	REQUIRE(rdata == NULL || *rdata == NULL);

	*name = dns_fixedname_name(&it->fixedname);
	*ttl = it->rdataset.ttl;

	dns_rdata_reset(&it->rdata);
	dns_rdataset_current(&it->rdataset, &it->rdata);

	if (rdataset != NULL)
		*rdataset = &it->rdataset;

	if (rdata != NULL)
		*rdata = &it->rdata;
}

static isc_result_t
in_rootns(dns_rdataset_t *rootns, dns_name_t *name) {
	isc_result_t result;
	dns_rdata_t rdata = DNS_RDATA_INIT;
	dns_rdata_ns_t ns;

	if (!dns_rdataset_isassociated(rootns))
		return (ISC_R_NOTFOUND);

	result = dns_rdataset_first(rootns);
	while (result == ISC_R_SUCCESS) {
		dns_rdataset_current(rootns, &rdata);
		result = dns_rdata_tostruct(&rdata, &ns, NULL);
		if (result != ISC_R_SUCCESS)
			return (result);
		if (dns_name_compare(name, &ns.name) == 0)
			return (ISC_R_SUCCESS);
		result = dns_rdataset_next(rootns);
		dns_rdata_reset(&rdata);
	}
	if (result == ISC_R_NOMORE)
		result = ISC_R_NOTFOUND;
	return (result);
}

static void
chase_cnamechain(dns_message_t *msg, dns_name_t *qname) {
	isc_result_t result;
	dns_rdataset_t *rdataset;
	dns_rdata_cname_t cname;
	dns_rdata_t rdata = DNS_RDATA_INIT;
	unsigned int i = msg->counts[DNS_SECTION_ANSWER];

	while (i-- > 0) {
		rdataset = NULL;
		result = dns_message_findname(msg, DNS_SECTION_ANSWER, qname,
				dns_rdatatype_cname, 0, NULL, &rdataset);
		if (result != ISC_R_SUCCESS)
			return;
		result = dns_rdataset_first(rdataset);
		check_result(result, "dns_rdataset_first");
		dns_rdata_reset(&rdata);
		dns_rdataset_current(rdataset, &rdata);
		result = dns_rdata_tostruct(&rdata, &cname, NULL);
		check_result(result, "dns_rdata_tostruct");
		dns_name_copy(&cname.cname, qname, NULL);
		dns_rdata_freestruct(&cname);
	}
}

isc_result_t
dns_ncache_getrdataset(dns_rdataset_t *ncacherdataset, dns_name_t *name,
		       dns_rdatatype_t type, dns_rdataset_t *rdataset)
{
	isc_result_t result;
	dns_rdata_t rdata = DNS_RDATA_INIT;
	isc_region_t remaining;
	isc_buffer_t source;
	dns_name_t tname;
	dns_rdatatype_t ttype;
	dns_trust_t trust = dns_trust_none;
	dns_rdataset_t clone;

	REQUIRE(ncacherdataset != NULL);
	REQUIRE(ncacherdataset->type == 0);
	REQUIRE((ncacherdataset->attributes & DNS_RDATASETATTR_NEGATIVE) != 0);
	REQUIRE(name != NULL);
	REQUIRE(!dns_rdataset_isassociated(rdataset));
	REQUIRE(type != dns_rdatatype_rrsig);

	dns_rdataset_init(&clone);
	dns_rdataset_clone(ncacherdataset, &clone);
	result = dns_rdataset_first(&clone);
	while (result == ISC_R_SUCCESS) {
		dns_rdataset_current(&clone, &rdata);
		isc_buffer_init(&source, rdata.data, rdata.length);
		isc_buffer_add(&source, rdata.length);
		dns_name_init(&tname, NULL);
		isc_buffer_remainingregion(&source, &remaining);
		dns_name_fromregion(&tname, &remaining);
		INSIST(remaining.length >= tname.length);
		isc_buffer_forward(&source, tname.length);
		remaining.length -= tname.length;

		INSIST(remaining.length >= 3);
		ttype = isc_buffer_getuint16(&source);

		if (ttype == type && dns_name_equal(&tname, name)) {
			trust = isc_buffer_getuint8(&source);
			INSIST(trust <= dns_trust_ultimate);
			isc_buffer_remainingregion(&source, &remaining);
			break;
		}
		result = dns_rdataset_next(&clone);
		dns_rdata_reset(&rdata);
	}
	dns_rdataset_disassociate(&clone);
	if (result == ISC_R_NOMORE)
		return (ISC_R_NOTFOUND);
	if (result != ISC_R_SUCCESS)
		return (result);

	INSIST(remaining.length != 0);

	rdataset->methods = &rdataset_methods;
	rdataset->rdclass = ncacherdataset->rdclass;
	rdataset->type = type;
	rdataset->covers = 0;
	rdataset->ttl = ncacherdataset->ttl;
	rdataset->trust = trust;
	rdataset->private1 = NULL;
	rdataset->private2 = NULL;

	rdataset->private3 = remaining.base;

	/*
	 * Reset iterator state.
	 */
	rdataset->privateuint4 = 0;
	rdataset->private5 = NULL;
	rdataset->private6 = NULL;
	return (ISC_R_SUCCESS);
}

isc_result_t
dns_ncache_towire(dns_rdataset_t *rdataset, dns_compress_t *cctx,
		  isc_buffer_t *target, unsigned int options,
		  unsigned int *countp)
{
	dns_rdata_t rdata = DNS_RDATA_INIT;
	isc_result_t result;
	isc_region_t remaining, tavailable;
	isc_buffer_t source, savedbuffer, rdlen;
	dns_name_t name;
	dns_rdatatype_t type;
	unsigned int i, rcount, count;

	/*
	 * Convert the negative caching rdataset 'rdataset' to wire format,
	 * compressing names as specified in 'cctx', and storing the result in
	 * 'target'.
	 */

	REQUIRE(rdataset != NULL);
	REQUIRE(rdataset->type == 0);
	REQUIRE((rdataset->attributes & DNS_RDATASETATTR_NEGATIVE) != 0);

	savedbuffer = *target;
	count = 0;

	result = dns_rdataset_first(rdataset);
	while (result == ISC_R_SUCCESS) {
		dns_rdataset_current(rdataset, &rdata);
		isc_buffer_init(&source, rdata.data, rdata.length);
		isc_buffer_add(&source, rdata.length);
		dns_name_init(&name, NULL);
		isc_buffer_remainingregion(&source, &remaining);
		dns_name_fromregion(&name, &remaining);
		INSIST(remaining.length >= name.length);
		isc_buffer_forward(&source, name.length);
		remaining.length -= name.length;

		INSIST(remaining.length >= 5);
		type = isc_buffer_getuint16(&source);
		isc_buffer_forward(&source, 1);
		rcount = isc_buffer_getuint16(&source);

		for (i = 0; i < rcount; i++) {
			/*
			 * Get the length of this rdata and set up an
			 * rdata structure for it.
			 */
			isc_buffer_remainingregion(&source, &remaining);
			INSIST(remaining.length >= 2);
			dns_rdata_reset(&rdata);
			rdata.length = isc_buffer_getuint16(&source);
			isc_buffer_remainingregion(&source, &remaining);
			rdata.data = remaining.base;
			rdata.type = type;
			rdata.rdclass = rdataset->rdclass;
			INSIST(remaining.length >= rdata.length);
			isc_buffer_forward(&source, rdata.length);

			if ((options & DNS_NCACHETOWIRE_OMITDNSSEC) != 0 &&
			    dns_rdatatype_isdnssec(type))
				continue;

			/*
			 * Write the name.
			 */
			dns_compress_setmethods(cctx, DNS_COMPRESS_GLOBAL14);
			result = dns_name_towire(&name, cctx, target);
			if (result != ISC_R_SUCCESS)
				goto rollback;

			/*
			 * See if we have space for type, class, ttl, and
			 * rdata length.  Write the type, class, and ttl.
			 */
			isc_buffer_availableregion(target, &tavailable);
			if (tavailable.length < 10) {
				result = ISC_R_NOSPACE;
				goto rollback;
			}
			isc_buffer_putuint16(target, type);
			isc_buffer_putuint16(target, rdataset->rdclass);
			isc_buffer_putuint32(target, rdataset->ttl);

			/*
			 * Save space for rdata length.
			 */
			rdlen = *target;
			isc_buffer_add(target, 2);

			/*
			 * Write the rdata.
			 */
			result = dns_rdata_towire(&rdata, cctx, target);
			if (result != ISC_R_SUCCESS)
				goto rollback;

			/*
			 * Set the rdata length field to the compressed
			 * length.
//.........这里部分代码省略.........

void
dns_root_checkhints(dns_view_t *view, dns_db_t *hints, dns_db_t *db) {
	isc_result_t result;
	dns_rdata_t rdata = DNS_RDATA_INIT;
	dns_rdata_ns_t ns;
	dns_rdataset_t hintns, rootns;
	const char *viewname = "", *sep = "";
	isc_stdtime_t now;
	dns_name_t *name;
	dns_fixedname_t fixed;

	REQUIRE(hints != NULL);
	REQUIRE(db != NULL);
	REQUIRE(view != NULL);

	isc_stdtime_get(&now);

	if (strcmp(view->name, "_bind") != 0 &&
	    strcmp(view->name, "_default") != 0) {
		viewname = view->name;
		sep = ": view ";
	}

	dns_rdataset_init(&hintns);
	dns_rdataset_init(&rootns);
	dns_fixedname_init(&fixed);
	name = dns_fixedname_name(&fixed);

	result = dns_db_find(hints, dns_rootname, NULL, dns_rdatatype_ns, 0,
			     now, NULL, name, &hintns, NULL);
	if (result != ISC_R_SUCCESS) {
		isc_log_write(dns_lctx, DNS_LOGCATEGORY_GENERAL,
			      DNS_LOGMODULE_HINTS, ISC_LOG_WARNING,
			      "checkhints%s%s: unable to get root NS rrset "
			      "from hints: %s", sep, viewname,
			      dns_result_totext(result));
		goto cleanup;
	}

	result = dns_db_find(db, dns_rootname, NULL, dns_rdatatype_ns, 0,
			     now, NULL, name, &rootns, NULL);
	if (result != ISC_R_SUCCESS) {
		isc_log_write(dns_lctx, DNS_LOGCATEGORY_GENERAL,
			      DNS_LOGMODULE_HINTS, ISC_LOG_WARNING,
			      "checkhints%s%s: unable to get root NS rrset "
			      "from cache: %s", sep, viewname,
			      dns_result_totext(result));
		goto cleanup;
	}

	/*
	 * Look for missing root NS names.
	 */
	result = dns_rdataset_first(&rootns);
	while (result == ISC_R_SUCCESS) {
		dns_rdataset_current(&rootns, &rdata);
		result = dns_rdata_tostruct(&rdata, &ns, NULL);
		RUNTIME_CHECK(result == ISC_R_SUCCESS);
		result = in_rootns(&hintns, &ns.name);
		if (result != ISC_R_SUCCESS) {
			char namebuf[DNS_NAME_FORMATSIZE];
			/* missing from hints */
			dns_name_format(&ns.name, namebuf, sizeof(namebuf));
			isc_log_write(dns_lctx, DNS_LOGCATEGORY_GENERAL,
				      DNS_LOGMODULE_HINTS, ISC_LOG_WARNING,
				      "checkhints%s%s: unable to find root "
				      "NS '%s' in hints", sep, viewname,
				      namebuf);
		} else
			check_address_records(view, hints, db, &ns.name, now);
		dns_rdata_reset(&rdata);
		result = dns_rdataset_next(&rootns);
	}
	if (result != ISC_R_NOMORE) {
		goto cleanup;
	}

	/*
	 * Look for extra root NS names.
	 */
	result = dns_rdataset_first(&hintns);
	while (result == ISC_R_SUCCESS) {
		dns_rdataset_current(&hintns, &rdata);
		result = dns_rdata_tostruct(&rdata, &ns, NULL);
		RUNTIME_CHECK(result == ISC_R_SUCCESS);
		result = in_rootns(&rootns, &ns.name);
		if (result != ISC_R_SUCCESS) {
			char namebuf[DNS_NAME_FORMATSIZE];
			/* extra entry in hints */
			dns_name_format(&ns.name, namebuf, sizeof(namebuf));
			isc_log_write(dns_lctx, DNS_LOGCATEGORY_GENERAL,
				      DNS_LOGMODULE_HINTS, ISC_LOG_WARNING,
				      "checkhints%s%s: extra NS '%s' in hints",
				      sep, viewname, namebuf);
		}
		dns_rdata_reset(&rdata);
		result = dns_rdataset_next(&hintns);
	}
	if (result != ISC_R_NOMORE) {
		goto cleanup;
//.........这里部分代码省略.........