C++ dns_name_clone函数代码示例

static inline isc_boolean_t
checknames_minfo(ARGS_CHECKNAMES) {
	isc_region_t region;
	dns_name_t name;

	REQUIRE(rdata->type == 14);

	UNUSED(owner);

	dns_rdata_toregion(rdata, &region);
	dns_name_init(&name, NULL);
	dns_name_fromregion(&name, &region);
	if (!dns_name_ismailbox(&name)) {
		if (bad != NULL)
			dns_name_clone(&name, bad);
		return (ISC_FALSE);
	}
	isc_region_consume(&region, name_length(&name));
	dns_name_fromregion(&name, &region);
	if (!dns_name_ismailbox(&name)) {
		if (bad != NULL)
			dns_name_clone(&name, bad);
		return (ISC_FALSE);
	}
	return (ISC_TRUE);
}

/*
 * Common routine to make query data
 */
static isc_result_t
make_querymessage(dns_message_t *message, dns_name_t *qname0,
		  dns_rdatatype_t rdtype)
{
	dns_name_t *qname = NULL;
	dns_rdataset_t *qrdataset = NULL;
	isc_result_t result;

	message->opcode = dns_opcode_query;
	message->rdclass = dns_rdataclass_in;

	result = dns_message_gettempname(message, &qname);
	if (result != ISC_R_SUCCESS)
		goto cleanup;

	result = dns_message_gettemprdataset(message, &qrdataset);
	if (result != ISC_R_SUCCESS)
		goto cleanup;

	dns_name_init(qname, NULL);
	dns_name_clone(qname0, qname);
	dns_rdataset_init(qrdataset);
	dns_rdataset_makequestion(qrdataset, message->rdclass, rdtype);
	ISC_LIST_APPEND(qname->list, qrdataset, link);
	dns_message_addname(message, qname, DNS_SECTION_QUESTION);

	return (ISC_R_SUCCESS);

 cleanup:
	if (qname != NULL)
		dns_message_puttempname(message, &qname);
	if (qrdataset != NULL)
		dns_message_puttemprdataset(message, &qrdataset);
	return (result);
}

static inline isc_boolean_t
checknames_ptr(ARGS_CHECKNAMES) {
	isc_region_t region;
	dns_name_t name;

	REQUIRE(rdata->type == dns_rdatatype_ptr);

	if (rdata->rdclass != dns_rdataclass_in)
	    return (ISC_TRUE);

	if (dns_name_isdnssd(owner))
		return (ISC_TRUE);

	if (dns_name_issubdomain(owner, &in_addr_arpa) ||
	    dns_name_issubdomain(owner, &ip6_arpa) ||
	    dns_name_issubdomain(owner, &ip6_int)) {
		dns_rdata_toregion(rdata, &region);
		dns_name_init(&name, NULL);
		dns_name_fromregion(&name, &region);
		if (!dns_name_ishostname(&name, ISC_FALSE)) {
			if (bad != NULL)
				dns_name_clone(&name, bad);
			return (ISC_FALSE);
		}
	}
	return (ISC_TRUE);
}

static isc_result_t
sendquery(isc_task_t *task) {
	dns_request_t *request;
	dns_message_t *message;
	dns_name_t *qname;
	dns_rdataset_t *qrdataset;
	isc_result_t result;
	dns_fixedname_t queryname;
	isc_buffer_t buf;
	static char host[256];
	int c;

	c = scanf("%255s", host);
	if (c == EOF)
		return ISC_R_NOMORE;

	onfly++;

	dns_fixedname_init(&queryname);
	isc_buffer_init(&buf, host, strlen(host));
	isc_buffer_add(&buf, strlen(host));
	result = dns_name_fromtext(dns_fixedname_name(&queryname), &buf,
				   dns_rootname, 0, NULL);
	CHECK("dns_name_fromtext", result);

	message = NULL;
	result = dns_message_create(mctx, DNS_MESSAGE_INTENTRENDER, &message);
	CHECK("dns_message_create", result);

	message->opcode = dns_opcode_query;
	message->flags |= DNS_MESSAGEFLAG_RD;
	message->rdclass = dns_rdataclass_in;
	message->id = (unsigned short)(random() & 0xFFFF);

	qname = NULL;
	result = dns_message_gettempname(message, &qname);
	CHECK("dns_message_gettempname", result);

	qrdataset = NULL;
	result = dns_message_gettemprdataset(message, &qrdataset);
	CHECK("dns_message_gettemprdataset", result);

	dns_name_init(qname, NULL);
	dns_name_clone(dns_fixedname_name(&queryname), qname);
	dns_rdataset_init(qrdataset);
	dns_rdataset_makequestion(qrdataset, dns_rdataclass_in,
				  dns_rdatatype_a);
	ISC_LIST_APPEND(qname->list, qrdataset, link);
	dns_message_addname(message, qname, DNS_SECTION_QUESTION);

	request = NULL;
	result = dns_request_createvia(requestmgr, message,
				       have_src ? &srcaddr : NULL, &dstaddr,
				       DNS_REQUESTOPT_TCP|DNS_REQUESTOPT_SHARE,
				       NULL, TIMEOUT, task, recvresponse,
				       message, &request);
	CHECK("dns_request_create", result);

	return ISC_R_SUCCESS;
}

isc_result_t
isc__rdatalist_getnoqname(dns_rdataset_t *rdataset, dns_name_t *name,
			 dns_rdataset_t *nsec, dns_rdataset_t *nsecsig)
{
	dns_rdataclass_t rdclass = rdataset->rdclass;
	dns_rdataset_t *tnsec = NULL;
	dns_rdataset_t *tnsecsig = NULL;
	dns_name_t *noqname = rdataset->private6;

	REQUIRE((rdataset->attributes & DNS_RDATASETATTR_NOQNAME) != 0);
	(void)dns_name_dynamic(noqname);	/* Sanity Check. */

	for (rdataset = ISC_LIST_HEAD(noqname->list);
	     rdataset != NULL;
	     rdataset = ISC_LIST_NEXT(rdataset, link))
	{
		if (rdataset->rdclass != rdclass)
			continue;
		if (rdataset->type == dns_rdatatype_nsec)
			tnsec = rdataset;
		if (rdataset->type == dns_rdatatype_rrsig &&
		    rdataset->covers == dns_rdatatype_nsec)
			tnsecsig = rdataset;
	}
	if (tnsec == NULL || tnsecsig == NULL)
		return (ISC_R_NOTFOUND);

	dns_name_clone(noqname, name);
	dns_rdataset_clone(tnsec, nsec);
	dns_rdataset_clone(tnsecsig, nsecsig);
	return (ISC_R_SUCCESS);
}

static isc_result_t
make_querymessage(dns_message_t *message, const char *namestr,
		  dns_rdatatype_t rdtype)
{
	dns_name_t *qname = NULL, *qname0;
	dns_rdataset_t *qrdataset = NULL;
	isc_result_t result;
	isc_buffer_t b;
	unsigned int namelen;

	REQUIRE(message != NULL);
	REQUIRE(namestr != NULL);

	/* Construct qname */
	namelen = strlen(namestr);
	isc_buffer_constinit(&b, namestr, namelen);
	isc_buffer_add(&b, namelen);
	dns_fixedname_init(&fixedqname);
	qname0 = dns_fixedname_name(&fixedqname);
	result = dns_name_fromtext(qname0, &b, dns_rootname, 0, NULL);
	if (result != ISC_R_SUCCESS) {
		fprintf(stderr, "failed to convert qname: %d\n", result);
		return (result);
	}

	/* Construct query message */
	message->opcode = dns_opcode_query;
	message->rdclass = dns_rdataclass_in;

	result = dns_message_gettempname(message, &qname);
	if (result != ISC_R_SUCCESS)
		goto cleanup;

	result = dns_message_gettemprdataset(message, &qrdataset);
	if (result != ISC_R_SUCCESS)
		goto cleanup;

	dns_name_init(qname, NULL);
	dns_name_clone(qname0, qname);
	dns_rdataset_init(qrdataset);
	dns_rdataset_makequestion(qrdataset, message->rdclass, rdtype);
	ISC_LIST_APPEND(qname->list, qrdataset, link);
	dns_message_addname(message, qname, DNS_SECTION_QUESTION);

	return (ISC_R_SUCCESS);

 cleanup:
	if (qname != NULL)
		dns_message_puttempname(message, &qname);
	if (qrdataset != NULL)
		dns_message_puttemprdataset(message, &qrdataset);
	dns_message_destroy(&message);
	return (result);
}

isc_result_t
dns_difftuple_create(isc_mem_t *mctx,
		     dns_diffop_t op, dns_name_t *name, dns_ttl_t ttl,
		     dns_rdata_t *rdata, dns_difftuple_t **tp)
{
	dns_difftuple_t *t;
	unsigned int size;
	unsigned char *datap;

	REQUIRE(tp != NULL && *tp == NULL);

	/*
	 * Create a new tuple.  The variable-size wire-format name data and
	 * rdata immediately follow the dns_difftuple_t structure
	 * in memory.
	 */
	size = sizeof(*t) + name->length + rdata->length;
	t = isc_mem_allocate(mctx, size);
	if (t == NULL)
		return (ISC_R_NOMEMORY);
	t->mctx = NULL;
	isc_mem_attach(mctx, &t->mctx);
	t->op = op;

	datap = (unsigned char *)(t + 1);

	memmove(datap, name->ndata, name->length);
	dns_name_init(&t->name, NULL);
	dns_name_clone(name, &t->name);
	t->name.ndata = datap;
	datap += name->length;

	t->ttl = ttl;

	memmove(datap, rdata->data, rdata->length);
	dns_rdata_init(&t->rdata);
	dns_rdata_clone(rdata, &t->rdata);
	t->rdata.data = datap;
	datap += rdata->length;

	ISC_LINK_INIT(&t->rdata, link);
	ISC_LINK_INIT(t, link);
	t->magic = DNS_DIFFTUPLE_MAGIC;

	INSIST(datap == (unsigned char *)t + size);

	*tp = t;
	return (ISC_R_SUCCESS);
}

static inline isc_boolean_t
checknames_ns(ARGS_CHECKNAMES) {
	isc_region_t region;
	dns_name_t name;

	REQUIRE(rdata->type == 2);

	UNUSED(owner);

	dns_rdata_toregion(rdata, &region);
	dns_name_init(&name, NULL);
	dns_name_fromregion(&name, &region);
	if (!dns_name_ishostname(&name, ISC_FALSE)) {
		if (bad != NULL)
			dns_name_clone(&name, bad);
		return (ISC_FALSE);
	}
	return (ISC_TRUE);
}

isc_result_t
isc__rdatalist_getclosest(dns_rdataset_t *rdataset, dns_name_t *name,
			  dns_rdataset_t *neg, dns_rdataset_t *negsig)
{
	dns_rdataclass_t rdclass = rdataset->rdclass;
	dns_rdataset_t *tneg = NULL;
	dns_rdataset_t *tnegsig = NULL;
	dns_name_t *closest = rdataset->private7;

	REQUIRE((rdataset->attributes & DNS_RDATASETATTR_CLOSEST) != 0);
	(void)dns_name_dynamic(closest);	/* Sanity Check. */

	for (rdataset = ISC_LIST_HEAD(closest->list);
	     rdataset != NULL;
	     rdataset = ISC_LIST_NEXT(rdataset, link))
	{
		if (rdataset->rdclass != rdclass)
			continue;
		if (rdataset->type == dns_rdatatype_nsec ||
		    rdataset->type == dns_rdatatype_nsec3)
			tneg = rdataset;
	}
	if (tneg == NULL)
		return (ISC_R_NOTFOUND);

	for (rdataset = ISC_LIST_HEAD(closest->list);
	     rdataset != NULL;
	     rdataset = ISC_LIST_NEXT(rdataset, link))
	{
		if (rdataset->type == dns_rdatatype_rrsig &&
		    rdataset->covers == tneg->type)
			tnegsig = rdataset;
	}
	if (tnegsig == NULL)
		return (ISC_R_NOTFOUND);

	dns_name_clone(closest, name);
	dns_rdataset_clone(tneg, neg);
	dns_rdataset_clone(tnegsig, negsig);
	return (ISC_R_SUCCESS);
}

isc_result_t ATTR_NONNULLS
dns_ns_buildrdata(dns_name_t *origin, dns_name_t *ns_name,
		   dns_rdataclass_t rdclass,
		   unsigned char *buffer,
		   dns_rdata_t *rdata) {
	dns_rdata_ns_t ns;
	isc_buffer_t rdatabuf;

	REQUIRE(origin != NULL);
	REQUIRE(ns_name != NULL);

	memset(buffer, 0, DNS_SOA_BUFFERSIZE);
	isc_buffer_init(&rdatabuf, buffer, DNS_SOA_BUFFERSIZE);

	ns.common.rdtype = dns_rdatatype_ns;
	ns.common.rdclass = rdclass;
	ns.mctx = NULL;
	dns_name_init(&ns.name, NULL);
	dns_name_clone(ns_name, &ns.name);

	return (dns_rdata_fromstruct(rdata, rdclass, dns_rdatatype_ns,
				      &ns, &rdatabuf));
}

static isc_result_t
add_ns(dns_db_t *db, dns_dbversion_t *version, const dns_name_t *name,
       const dns_name_t *nsname)
{
	dns_dbnode_t *node = NULL;
	dns_rdata_ns_t ns;
	dns_rdata_t rdata = DNS_RDATA_INIT;
	dns_rdatalist_t rdatalist;
	dns_rdataset_t rdataset;
	isc_result_t result;
	isc_buffer_t b;
	unsigned char buf[DNS_NAME_MAXWIRE];

	isc_buffer_init(&b, buf, sizeof(buf));

	dns_rdataset_init(&rdataset);
	dns_rdatalist_init(&rdatalist);
	ns.common.rdtype = dns_rdatatype_ns;
	ns.common.rdclass = dns_db_class(db);
	ns.mctx = NULL;
	dns_name_init(&ns.name, NULL);
	dns_name_clone(nsname, &ns.name);
	CHECK(dns_rdata_fromstruct(&rdata, dns_db_class(db), dns_rdatatype_ns,
				   &ns, &b));
	rdatalist.type = rdata.type;
	rdatalist.covers = 0;
	rdatalist.rdclass = rdata.rdclass;
	rdatalist.ttl = 86400;
	ISC_LIST_APPEND(rdatalist.rdata, &rdata, link);
	CHECK(dns_rdatalist_tordataset(&rdatalist, &rdataset));
	CHECK(dns_db_findnode(db, name, ISC_TRUE, &node));
	CHECK(dns_db_addrdataset(db, node, version, 0, &rdataset, 0, NULL));
 cleanup:
	if (node != NULL)
		dns_db_detachnode(db, &node);
	return (result);
}

/*%
 * Configure static-stub zone.
 */
static isc_result_t
configure_staticstub(const cfg_obj_t *zconfig, dns_zone_t *zone,
		     const char *zname, const char *dbtype)
{
	int i = 0;
	const cfg_obj_t *obj;
	isc_mem_t *mctx = dns_zone_getmctx(zone);
	dns_db_t *db = NULL;
	dns_dbversion_t *dbversion = NULL;
	dns_dbnode_t *apexnode = NULL;
	dns_name_t apexname;
	isc_result_t result;
	dns_rdataset_t rdataset;
	dns_rdatalist_t rdatalist_ns, rdatalist_a, rdatalist_aaaa;
	dns_rdatalist_t* rdatalists[] = {
		&rdatalist_ns, &rdatalist_a, &rdatalist_aaaa, NULL
	};
	dns_rdata_t *rdata;
	isc_region_t region;

	/* Create the DB beforehand */
	RETERR(dns_db_create(mctx, dbtype, dns_zone_getorigin(zone),
			     dns_dbtype_stub, dns_zone_getclass(zone),
			     0, NULL, &db));
	dns_zone_setdb(zone, db);

	dns_rdatalist_init(&rdatalist_ns);
	rdatalist_ns.rdclass = dns_zone_getclass(zone);
	rdatalist_ns.type = dns_rdatatype_ns;
	rdatalist_ns.ttl = STATICSTUB_SERVER_TTL;

	dns_rdatalist_init(&rdatalist_a);
	rdatalist_a.rdclass = dns_zone_getclass(zone);
	rdatalist_a.type = dns_rdatatype_a;
	rdatalist_a.ttl = STATICSTUB_SERVER_TTL;

	dns_rdatalist_init(&rdatalist_aaaa);
	rdatalist_aaaa.rdclass = dns_zone_getclass(zone);
	rdatalist_aaaa.type = dns_rdatatype_aaaa;
	rdatalist_aaaa.ttl = STATICSTUB_SERVER_TTL;

	/* Prepare zone RRs from the configuration */
	obj = NULL;
	result = cfg_map_get(zconfig, "server-addresses", &obj);
	if (result == ISC_R_SUCCESS) {
		INSIST(obj != NULL);
		result = configure_staticstub_serveraddrs(obj, zone,
							  &rdatalist_ns,
							  &rdatalist_a,
							  &rdatalist_aaaa);
		if (result != ISC_R_SUCCESS)
			goto cleanup;
	}

	obj = NULL;
	result = cfg_map_get(zconfig, "server-names", &obj);
	if (result == ISC_R_SUCCESS) {
		INSIST(obj != NULL);
		result = configure_staticstub_servernames(obj, zone,
							  &rdatalist_ns,
							  zname);
		if (result != ISC_R_SUCCESS)
			goto cleanup;
	}

	/*
	 * Sanity check: there should be at least one NS RR at the zone apex
	 * to trigger delegation.
	 */
	if (ISC_LIST_EMPTY(rdatalist_ns.rdata)) {
		isc_log_write(ns_g_lctx, NS_LOGCATEGORY_GENERAL,
			      NS_LOGMODULE_SERVER, ISC_LOG_ERROR,
			      "No NS record is configured for a "
			      "static-stub zone '%s'", zname);
		result = ISC_R_FAILURE;
		goto cleanup;
	}

	/*
	 * Now add NS and glue A/AAAA RRsets to the zone DB.
	 * First open a new version for the add operation and get a pointer
	 * to the apex node (all RRs are of the apex name).
	 */
	result = dns_db_newversion(db, &dbversion);
	if (result != ISC_R_SUCCESS)
		goto cleanup;
	dns_name_init(&apexname, NULL);
	dns_name_clone(dns_zone_getorigin(zone), &apexname);
	result = dns_db_findnode(db, &apexname, ISC_FALSE, &apexnode);
	if (result != ISC_R_SUCCESS)
		goto cleanup;

	/* Add NS RRset */
	dns_rdataset_init(&rdataset);
	RUNTIME_CHECK(dns_rdatalist_tordataset(&rdatalist_ns, &rdataset)
		      == ISC_R_SUCCESS);
	result = dns_db_addrdataset(db, apexnode, dbversion, 0, &rdataset,
//.........这里部分代码省略.........

isc_result_t
dns_name_towire(dns_name_t *name, dns_compress_t *cctx, isc_buffer_t *target) {
	unsigned int methods;
	isc_uint16_t offset;
	dns_name_t gp;	/* Global compression prefix */
	isc_boolean_t gf;	/* Global compression target found */
	isc_uint16_t go;	/* Global compression offset */
	dns_offsets_t clo;
	dns_name_t clname;

	/*
	 * Convert 'name' into wire format, compressing it as specified by the
	 * compression context 'cctx', and storing the result in 'target'.
	 */

	REQUIRE(VALID_NAME(name));
	REQUIRE(cctx != NULL);
	REQUIRE(ISC_BUFFER_VALID(target));

	/*
	 * If 'name' doesn't have an offsets table, make a clone which
	 * has one.
	 */
	if (name->offsets == NULL) {
		DNS_NAME_INIT(&clname, clo);
		dns_name_clone(name, &clname);
		name = &clname;
	}
	DNS_NAME_INIT(&gp, NULL);

	offset = target->used;	/*XXX*/

	methods = dns_compress_getmethods(cctx);

	if ((methods & DNS_COMPRESS_GLOBAL14) != 0)
		gf = dns_compress_findglobal(cctx, name, &gp, &go);
	else
		gf = ISC_FALSE;

	/*
	 * If the offset is too high for 14 bit global compression, we're
	 * out of luck.
	 */
	if (gf && go >= 0x4000)
		gf = ISC_FALSE;

	/*
	 * Will the compression pointer reduce the message size?
	 */
	if (gf && (gp.length + 2) >= name->length)
		gf = ISC_FALSE;

	if (gf) {
		if (target->length - target->used < gp.length)
			return (ISC_R_NOSPACE);
		(void)memcpy((unsigned char *)target->base + target->used,
			     gp.ndata, (size_t)gp.length);
		isc_buffer_add(target, gp.length);
		go |= 0xc000;
		if (target->length - target->used < 2)
			return (ISC_R_NOSPACE);
		isc_buffer_putuint16(target, go);
		if (gp.length != 0)
			dns_compress_add(cctx, name, &gp, offset);
	} else {
		if (target->length - target->used < name->length)
			return (ISC_R_NOSPACE);
		(void)memcpy((unsigned char *)target->base + target->used,
			     name->ndata, (size_t)name->length);
		isc_buffer_add(target, name->length);
		dns_compress_add(cctx, name, name, offset);
	}
	return (ISC_R_SUCCESS);
}

isc_result_t
dns_tkey_processquery(dns_message_t *msg, dns_tkeyctx_t *tctx,
		      dns_tsig_keyring_t *ring)
{
	isc_result_t result = ISC_R_SUCCESS;
	dns_rdata_tkey_t tkeyin, tkeyout;
	isc_boolean_t freetkeyin = ISC_FALSE;
	dns_name_t *qname, *name, *keyname, *signer, tsigner;
	dns_fixedname_t fkeyname;
	dns_rdataset_t *tkeyset;
	dns_rdata_t rdata;
	dns_namelist_t namelist;
	char tkeyoutdata[512];
	isc_buffer_t tkeyoutbuf;

	REQUIRE(msg != NULL);
	REQUIRE(tctx != NULL);
	REQUIRE(ring != NULL);

	ISC_LIST_INIT(namelist);

	/*
	 * Interpret the question section.
	 */
	result = dns_message_firstname(msg, DNS_SECTION_QUESTION);
	if (result != ISC_R_SUCCESS)
		return (DNS_R_FORMERR);

	qname = NULL;
	dns_message_currentname(msg, DNS_SECTION_QUESTION, &qname);

	/*
	 * Look for a TKEY record that matches the question.
	 */
	tkeyset = NULL;
	name = NULL;
	result = dns_message_findname(msg, DNS_SECTION_ADDITIONAL, qname,
				      dns_rdatatype_tkey, 0, &name, &tkeyset);
	if (result != ISC_R_SUCCESS) {
		/*
		 * Try the answer section, since that's where Win2000
		 * puts it.
		 */
		name = NULL;
		if (dns_message_findname(msg, DNS_SECTION_ANSWER, qname,
					 dns_rdatatype_tkey, 0, &name,
					 &tkeyset) != ISC_R_SUCCESS) {
			result = DNS_R_FORMERR;
			tkey_log("dns_tkey_processquery: couldn't find a TKEY "
				 "matching the question");
			goto failure;
		}
	}
	result = dns_rdataset_first(tkeyset);
	if (result != ISC_R_SUCCESS) {
		result = DNS_R_FORMERR;
		goto failure;
	}
	dns_rdata_init(&rdata);
	dns_rdataset_current(tkeyset, &rdata);

	RETERR(dns_rdata_tostruct(&rdata, &tkeyin, NULL));
	freetkeyin = ISC_TRUE;

	if (tkeyin.error != dns_rcode_noerror) {
		result = DNS_R_FORMERR;
		goto failure;
	}

	/*
	 * Before we go any farther, verify that the message was signed.
	 * GSSAPI TKEY doesn't require a signature, the rest do.
	 */
	dns_name_init(&tsigner, NULL);
	result = dns_message_signer(msg, &tsigner);
	if (result != ISC_R_SUCCESS) {
		if (tkeyin.mode == DNS_TKEYMODE_GSSAPI &&
		    result == ISC_R_NOTFOUND)
		       signer = NULL;
		else {
			tkey_log("dns_tkey_processquery: query was not "
				 "properly signed - rejecting");
			result = DNS_R_FORMERR;
			goto failure;
		}
	} else
		signer = &tsigner;

	tkeyout.common.rdclass = tkeyin.common.rdclass;
	tkeyout.common.rdtype = tkeyin.common.rdtype;
	ISC_LINK_INIT(&tkeyout.common, link);
	tkeyout.mctx = msg->mctx;

	dns_name_init(&tkeyout.algorithm, NULL);
	dns_name_clone(&tkeyin.algorithm, &tkeyout.algorithm);

	tkeyout.inception = tkeyout.expire = 0;
	tkeyout.mode = tkeyin.mode;
	tkeyout.error = 0;
	tkeyout.keylen = tkeyout.otherlen = 0;
//.........这里部分代码省略.........

static isc_result_t
process_dhtkey(dns_message_t *msg, dns_name_t *signer, dns_name_t *name,
	       dns_rdata_tkey_t *tkeyin, dns_tkeyctx_t *tctx,
	       dns_rdata_tkey_t *tkeyout,
	       dns_tsig_keyring_t *ring, dns_namelist_t *namelist)
{
	isc_result_t result = ISC_R_SUCCESS;
	dns_name_t *keyname, ourname;
	dns_rdataset_t *keyset = NULL;
	dns_rdata_t keyrdata = DNS_RDATA_INIT, ourkeyrdata = DNS_RDATA_INIT;
	isc_boolean_t found_key = ISC_FALSE, found_incompatible = ISC_FALSE;
	dst_key_t *pubkey = NULL;
	isc_buffer_t ourkeybuf, *shared = NULL;
	isc_region_t r, r2, ourkeyr;
	unsigned char keydata[DST_KEY_MAXSIZE];
	unsigned int sharedsize;
	isc_buffer_t secret;
	unsigned char *randomdata = NULL, secretdata[256];
	dns_ttl_t ttl = 0;

	if (tctx->dhkey == NULL) {
		tkey_log("process_dhtkey: tkey-dhkey not defined");
		tkeyout->error = dns_tsigerror_badalg;
		return (DNS_R_REFUSED);
	}

	if (!dns_name_equal(&tkeyin->algorithm, DNS_TSIG_HMACMD5_NAME)) {
		tkey_log("process_dhtkey: algorithms other than "
			 "hmac-md5 are not supported");
		tkeyout->error = dns_tsigerror_badalg;
		return (ISC_R_SUCCESS);
	}

	/*
	 * Look for a DH KEY record that will work with ours.
	 */
	for (result = dns_message_firstname(msg, DNS_SECTION_ADDITIONAL);
	     result == ISC_R_SUCCESS && !found_key;
	     result = dns_message_nextname(msg, DNS_SECTION_ADDITIONAL)) {
		keyname = NULL;
		dns_message_currentname(msg, DNS_SECTION_ADDITIONAL, &keyname);
		keyset = NULL;
		result = dns_message_findtype(keyname, dns_rdatatype_key, 0,
					      &keyset);
		if (result != ISC_R_SUCCESS)
			continue;

		for (result = dns_rdataset_first(keyset);
		     result == ISC_R_SUCCESS && !found_key;
		     result = dns_rdataset_next(keyset)) {
			dns_rdataset_current(keyset, &keyrdata);
			pubkey = NULL;
			result = dns_dnssec_keyfromrdata(keyname, &keyrdata,
							 msg->mctx, &pubkey);
			if (result != ISC_R_SUCCESS) {
				dns_rdata_reset(&keyrdata);
				continue;
			}
			if (dst_key_alg(pubkey) == DNS_KEYALG_DH) {
				if (dst_key_paramcompare(pubkey, tctx->dhkey))
				{
					found_key = ISC_TRUE;
					ttl = keyset->ttl;
					break;
				} else
					found_incompatible = ISC_TRUE;
			}
			dst_key_free(&pubkey);
			dns_rdata_reset(&keyrdata);
		}
	}

	if (!found_key) {
		if (found_incompatible) {
			tkey_log("process_dhtkey: found an incompatible key");
			tkeyout->error = dns_tsigerror_badkey;
			return (ISC_R_SUCCESS);
		} else {
			tkey_log("process_dhtkey: failed to find a key");
			return (DNS_R_FORMERR);
		}
	}

	RETERR(add_rdata_to_list(msg, keyname, &keyrdata, ttl, namelist));

	isc_buffer_init(&ourkeybuf, keydata, sizeof(keydata));
	RETERR(dst_key_todns(tctx->dhkey, &ourkeybuf));
	isc_buffer_usedregion(&ourkeybuf, &ourkeyr);
	dns_rdata_fromregion(&ourkeyrdata, dns_rdataclass_any,
			     dns_rdatatype_key, &ourkeyr);

	dns_name_init(&ourname, NULL);
	dns_name_clone(dst_key_name(tctx->dhkey), &ourname);

	/*
	 * XXXBEW The TTL should be obtained from the database, if it exists.
	 */
	RETERR(add_rdata_to_list(msg, &ourname, &ourkeyrdata, 0, namelist));

	RETERR(dst_key_secretsize(tctx->dhkey, &sharedsize));
//.........这里部分代码省略.........