Exemplo n.º 1
0
void
ns_xfr_start(ns_client_t *client, dns_rdatatype_t reqtype) {
	isc_result_t result;
	dns_name_t *question_name;
	dns_rdataset_t *question_rdataset;
	dns_zone_t *zone = NULL, *raw = NULL, *mayberaw;
	dns_db_t *db = NULL;
	dns_dbversion_t *ver = NULL;
	dns_rdataclass_t question_class;
	rrstream_t *soa_stream = NULL;
	rrstream_t *data_stream = NULL;
	rrstream_t *stream = NULL;
	dns_difftuple_t *current_soa_tuple = NULL;
	dns_name_t *soa_name;
	dns_rdataset_t *soa_rdataset;
	dns_rdata_t soa_rdata = DNS_RDATA_INIT;
	isc_boolean_t have_soa = ISC_FALSE;
	const char *mnemonic = NULL;
	isc_mem_t *mctx = client->mctx;
	dns_message_t *request = client->message;
	xfrout_ctx_t *xfr = NULL;
	isc_quota_t *quota = NULL;
	dns_transfer_format_t format = client->view->transfer_format;
	isc_netaddr_t na;
	dns_peer_t *peer = NULL;
	isc_buffer_t *tsigbuf = NULL;
	char *journalfile;
	char msg[NS_CLIENT_ACLMSGSIZE("zone transfer")];
	char keyname[DNS_NAME_FORMATSIZE];
	isc_boolean_t is_poll = ISC_FALSE;
	isc_boolean_t is_dlz = ISC_FALSE;
	isc_boolean_t is_ixfr = ISC_FALSE;
	isc_uint32_t begin_serial = 0, current_serial;

	switch (reqtype) {
	case dns_rdatatype_axfr:
		mnemonic = "AXFR";
		break;
	case dns_rdatatype_ixfr:
		mnemonic = "IXFR";
		break;
	default:
		INSIST(0);
		break;
	}

	ns_client_log(client,
		      DNS_LOGCATEGORY_XFER_OUT, NS_LOGMODULE_XFER_OUT,
		      ISC_LOG_DEBUG(6), "%s request", mnemonic);
	/*
	 * Apply quota.
	 */
	result = isc_quota_attach(&ns_g_server->xfroutquota, &quota);
	if (result != ISC_R_SUCCESS) {
		isc_log_write(XFROUT_COMMON_LOGARGS, ISC_LOG_WARNING,
			      "%s request denied: %s", mnemonic,
			      isc_result_totext(result));
		goto failure;
	}

	/*
	 * Interpret the question section.
	 */
	result = dns_message_firstname(request, DNS_SECTION_QUESTION);
	INSIST(result == ISC_R_SUCCESS);

	/*
	 * The question section must contain exactly one question, and
	 * it must be for AXFR/IXFR as appropriate.
	 */
	question_name = NULL;
	dns_message_currentname(request, DNS_SECTION_QUESTION, &question_name);
	question_rdataset = ISC_LIST_HEAD(question_name->list);
	question_class = question_rdataset->rdclass;
	INSIST(question_rdataset->type == reqtype);
	if (ISC_LIST_NEXT(question_rdataset, link) != NULL)
		FAILC(DNS_R_FORMERR, "multiple questions");
	result = dns_message_nextname(request, DNS_SECTION_QUESTION);
	if (result != ISC_R_NOMORE)
		FAILC(DNS_R_FORMERR, "multiple questions");

	result = dns_zt_find(client->view->zonetable, question_name, 0, NULL,
			     &zone);

	if (result != ISC_R_SUCCESS) {
		/*
		 * Normal zone table does not have a match.
		 * Try the DLZ database
		 */
		// Temporary: only searching the first DLZ database
		if (! ISC_LIST_EMPTY(client->view->dlz_searched)) {
			result = dns_dlzallowzonexfr(client->view,
						     question_name,
						     &client->peeraddr,
						     &db);

			pfilter_notify(result, client, "zonexfr");
			if (result == ISC_R_NOPERM) {
				char _buf1[DNS_NAME_FORMATSIZE];
				char _buf2[DNS_RDATACLASS_FORMATSIZE];

				result = DNS_R_REFUSED;
				dns_name_format(question_name, _buf1,
						sizeof(_buf1));
				dns_rdataclass_format(question_class,
						      _buf2, sizeof(_buf2));
				ns_client_log(client, DNS_LOGCATEGORY_SECURITY,
					      NS_LOGMODULE_XFER_OUT,
					      ISC_LOG_ERROR,
					      "zone transfer '%s/%s' denied",
					      _buf1, _buf2);
				goto failure;
			}
			if (result != ISC_R_SUCCESS)
				FAILQ(DNS_R_NOTAUTH, "non-authoritative zone",
				      question_name, question_class);
			is_dlz = ISC_TRUE;
		} else {
			/*
			 * not DLZ and not in normal zone table, we are
			 * not authoritative
			 */
			FAILQ(DNS_R_NOTAUTH, "non-authoritative zone",
			      question_name, question_class);
		}
	} else {
		/* zone table has a match */
		switch(dns_zone_gettype(zone)) {
			/* Master and slave zones are OK for transfer. */
			case dns_zone_master:
			case dns_zone_slave:
			case dns_zone_dlz:
				break;
			default:
				FAILQ(DNS_R_NOTAUTH, "non-authoritative zone",
				      question_name, question_class);
			}
		CHECK(dns_zone_getdb(zone, &db));
		dns_db_currentversion(db, &ver);
	}

	xfrout_log1(client, question_name, question_class, ISC_LOG_DEBUG(6),
		    "%s question section OK", mnemonic);

	/*
	 * Check the authority section.  Look for a SOA record with
	 * the same name and class as the question.
	 */
	for (result = dns_message_firstname(request, DNS_SECTION_AUTHORITY);
	     result == ISC_R_SUCCESS;
	     result = dns_message_nextname(request, DNS_SECTION_AUTHORITY))
	{
		soa_name = NULL;
		dns_message_currentname(request, DNS_SECTION_AUTHORITY,
					&soa_name);

		/*
		 * Ignore data whose owner name is not the zone apex.
		 */
		if (! dns_name_equal(soa_name, question_name))
			continue;

		for (soa_rdataset = ISC_LIST_HEAD(soa_name->list);
		     soa_rdataset != NULL;
		     soa_rdataset = ISC_LIST_NEXT(soa_rdataset, link))
		{
			/*
			 * Ignore non-SOA data.
			 */
			if (soa_rdataset->type != dns_rdatatype_soa)
				continue;
			if (soa_rdataset->rdclass != question_class)
				continue;

			CHECK(dns_rdataset_first(soa_rdataset));
			dns_rdataset_current(soa_rdataset, &soa_rdata);
			result = dns_rdataset_next(soa_rdataset);
			if (result == ISC_R_SUCCESS)
				FAILC(DNS_R_FORMERR,
				      "IXFR authority section "
				      "has multiple SOAs");
			have_soa = ISC_TRUE;
			goto got_soa;
		}
	}
 got_soa:
	if (result != ISC_R_NOMORE)
		CHECK(result);

	xfrout_log1(client, question_name, question_class, ISC_LOG_DEBUG(6),
		    "%s authority section OK", mnemonic);

	/*
	 * If not a DLZ zone, decide whether to allow this transfer.
	 */
	if (!is_dlz) {
		ns_client_aclmsg("zone transfer", question_name, reqtype,
				 client->view->rdclass, msg, sizeof(msg));
		CHECK(ns_client_checkacl(client, NULL, msg,
					 dns_zone_getxfracl(zone),
					 ISC_TRUE, ISC_LOG_ERROR));
	}

	/*
	 * AXFR over UDP is not possible.
	 */
	if (reqtype == dns_rdatatype_axfr &&
	    (client->attributes & NS_CLIENTATTR_TCP) == 0)
		FAILC(DNS_R_FORMERR, "attempted AXFR over UDP");

	/*
	 * Look up the requesting server in the peer table.
	 */
	isc_netaddr_fromsockaddr(&na, &client->peeraddr);
	(void)dns_peerlist_peerbyaddr(client->view->peers, &na, &peer);

	/*
	 * Decide on the transfer format (one-answer or many-answers).
	 */
	if (peer != NULL)
		(void)dns_peer_gettransferformat(peer, &format);

	/*
	 * Get a dynamically allocated copy of the current SOA.
	 */
	if (is_dlz)
		dns_db_currentversion(db, &ver);

	CHECK(dns_db_createsoatuple(db, ver, mctx, DNS_DIFFOP_EXISTS,
				    &current_soa_tuple));

	current_serial = dns_soa_getserial(&current_soa_tuple->rdata);
	if (reqtype == dns_rdatatype_ixfr) {
		isc_boolean_t provide_ixfr;

		/*
		 * Outgoing IXFR may have been disabled for this peer
		 * or globally.
		 */
		provide_ixfr = client->view->provideixfr;
		if (peer != NULL)
			(void) dns_peer_getprovideixfr(peer, &provide_ixfr);
		if (provide_ixfr == ISC_FALSE)
			goto axfr_fallback;

		if (! have_soa)
			FAILC(DNS_R_FORMERR,
			      "IXFR request missing SOA");

		begin_serial = dns_soa_getserial(&soa_rdata);

		/*
		 * RFC1995 says "If an IXFR query with the same or
		 * newer version number than that of the server
		 * is received, it is replied to with a single SOA
		 * record of the server's current version, just as
		 * in AXFR".  The claim about AXFR is incorrect,
		 * but other than that, we do as the RFC says.
		 *
		 * Sending a single SOA record is also how we refuse
		 * IXFR over UDP (currently, we always do).
		 */
		if (DNS_SERIAL_GE(begin_serial, current_serial) ||
		    (client->attributes & NS_CLIENTATTR_TCP) == 0)
		{
			CHECK(soa_rrstream_create(mctx, db, ver, &stream));
			is_poll = ISC_TRUE;
			goto have_stream;
		}
		journalfile = is_dlz ? NULL : dns_zone_getjournal(zone);
		if (journalfile != NULL)
			result = ixfr_rrstream_create(mctx,
						      journalfile,
						      begin_serial,
						      current_serial,
						      &data_stream);
		else
			result = ISC_R_NOTFOUND;
		if (result == ISC_R_NOTFOUND ||
		    result == ISC_R_RANGE) {
			xfrout_log1(client, question_name, question_class,
				    ISC_LOG_DEBUG(4),
				    "IXFR version not in journal, "
				    "falling back to AXFR");
			mnemonic = "AXFR-style IXFR";
			goto axfr_fallback;
		}
		CHECK(result);
		is_ixfr = ISC_TRUE;
	} else {
	axfr_fallback:
		CHECK(axfr_rrstream_create(mctx, db, ver, &data_stream));
	}

	/*
	 * Bracket the data stream with SOAs.
	 */
	CHECK(soa_rrstream_create(mctx, db, ver, &soa_stream));
	CHECK(compound_rrstream_create(mctx, &soa_stream, &data_stream,
				       &stream));
	soa_stream = NULL;
	data_stream = NULL;

 have_stream:
	CHECK(dns_message_getquerytsig(request, mctx, &tsigbuf));
	/*
	 * Create the xfrout context object.  This transfers the ownership
	 * of "stream", "db", "ver", and "quota" to the xfrout context object.
	 */



	if (is_dlz)
		CHECK(xfrout_ctx_create(mctx, client, request->id,
					question_name, reqtype, question_class,
					zone, db, ver, quota, stream,
					dns_message_gettsigkey(request),
					tsigbuf,
					3600,
					3600,
					(format == dns_many_answers) ?
					ISC_TRUE : ISC_FALSE,
					&xfr));
	else
		CHECK(xfrout_ctx_create(mctx, client, request->id,
					question_name, reqtype, question_class,
					zone, db, ver, quota, stream,
					dns_message_gettsigkey(request),
					tsigbuf,
					dns_zone_getmaxxfrout(zone),
					dns_zone_getidleout(zone),
					(format == dns_many_answers) ?
					ISC_TRUE : ISC_FALSE,
					&xfr));

	xfr->mnemonic = mnemonic;
	stream = NULL;
	quota = NULL;

	CHECK(xfr->stream->methods->first(xfr->stream));

	if (xfr->tsigkey != NULL)
		dns_name_format(&xfr->tsigkey->name, keyname, sizeof(keyname));
	else
		keyname[0] = '\0';
	if (is_poll)
		xfrout_log1(client, question_name, question_class,
			    ISC_LOG_DEBUG(1), "IXFR poll up to date%s%s",
			    (xfr->tsigkey != NULL) ? ": TSIG " : "", keyname);
	else if (is_ixfr)
		xfrout_log1(client, question_name, question_class,
			    ISC_LOG_INFO, "%s started%s%s (serial %u -> %u)",
			    mnemonic, (xfr->tsigkey != NULL) ? ": TSIG " : "",
			    keyname, begin_serial, current_serial);
	else
		xfrout_log1(client, question_name, question_class,
			    ISC_LOG_INFO, "%s started%s%s (serial %u)",
			    mnemonic, (xfr->tsigkey != NULL) ? ": TSIG " : "",
			    keyname, current_serial);


	if (zone != NULL) {
		dns_zone_getraw(zone, &raw);
		mayberaw = (raw != NULL) ? raw : zone;
		if ((client->attributes & NS_CLIENTATTR_WANTEXPIRE) != 0 &&
		    dns_zone_gettype(mayberaw) == dns_zone_slave) {
			isc_time_t expiretime;
			isc_uint32_t secs;
			dns_zone_getexpiretime(zone, &expiretime);
			secs = isc_time_seconds(&expiretime);
			if (secs >= client->now && result == ISC_R_SUCCESS) {
				client->attributes |= NS_CLIENTATTR_HAVEEXPIRE;
				client->expire = secs - client->now;
			}
		}
		if (raw != NULL)
			dns_zone_detach(&raw);
	}

	/*
	 * Hand the context over to sendstream().  Set xfr to NULL;
	 * sendstream() is responsible for either passing the
	 * context on to a later event handler or destroying it.
	 */
	sendstream(xfr);
	xfr = NULL;

	result = ISC_R_SUCCESS;

 failure:
	if (result == DNS_R_REFUSED)
		inc_stats(zone, dns_nsstatscounter_xfrrej);
	if (quota != NULL)
		isc_quota_detach(&quota);
	if (current_soa_tuple != NULL)
		dns_difftuple_free(&current_soa_tuple);
	if (stream != NULL)
		stream->methods->destroy(&stream);
	if (soa_stream != NULL)
		soa_stream->methods->destroy(&soa_stream);
	if (data_stream != NULL)
		data_stream->methods->destroy(&data_stream);
	if (ver != NULL)
		dns_db_closeversion(db, &ver, ISC_FALSE);
	if (db != NULL)
		dns_db_detach(&db);
	if (zone != NULL)
		dns_zone_detach(&zone);
	/* XXX kludge */
	if (xfr != NULL) {
		xfrout_fail(xfr, result, "setting up zone transfer");
	} else if (result != ISC_R_SUCCESS) {
		ns_client_log(client, DNS_LOGCATEGORY_XFER_OUT,
			      NS_LOGMODULE_XFER_OUT,
			      ISC_LOG_DEBUG(3), "zone transfer setup failed");
		ns_client_error(client, result);
	}
}
Exemplo n.º 2
0
ATF_TC_BODY(tsig_tcp, tc) {
	const dns_name_t *tsigowner = NULL;
	dns_fixedname_t fkeyname;
	dns_message_t *msg = NULL;
	dns_name_t *keyname;
	dns_tsig_keyring_t *ring = NULL;
	dns_tsigkey_t *key = NULL;
	isc_buffer_t *buf = NULL;
	isc_buffer_t *querytsig = NULL;
	isc_buffer_t *tsigin = NULL;
	isc_buffer_t *tsigout = NULL;
	isc_result_t result;
	unsigned char secret[16] = { 0 };
	dst_context_t *tsigctx = NULL;
	dst_context_t *outctx = NULL;

	UNUSED(tc);

	result = dns_test_begin(stderr, ISC_TRUE);
	ATF_REQUIRE_EQ(result, ISC_R_SUCCESS);

	/* isc_log_setdebuglevel(lctx, 99); */

	dns_fixedname_init(&fkeyname);
	keyname = dns_fixedname_name(&fkeyname);
	result = dns_name_fromstring(keyname, "test", 0, NULL);
	ATF_REQUIRE_EQ(result, ISC_R_SUCCESS);

	result = dns_tsigkeyring_create(mctx, &ring);
	ATF_REQUIRE_EQ(result, ISC_R_SUCCESS);

	result = dns_tsigkey_create(keyname, dns_tsig_hmacsha256_name,
				    secret, sizeof(secret), ISC_FALSE,
				    NULL, 0, 0, mctx, ring, &key);
	ATF_REQUIRE_EQ(result, ISC_R_SUCCESS);

	/*
	 * Create request.
	 */
	result = isc_buffer_allocate(mctx, &buf, 65535);
	ATF_REQUIRE_EQ(result, ISC_R_SUCCESS);
	render(buf, 0, key, &tsigout, &querytsig, NULL);
	isc_buffer_free(&buf);

	/*
	 * Create response message 1.
	 */
	result = isc_buffer_allocate(mctx, &buf, 65535);
	ATF_REQUIRE_EQ(result, ISC_R_SUCCESS);
	render(buf, DNS_MESSAGEFLAG_QR, key, &querytsig, &tsigout, NULL);

	/*
	 * Process response message 1.
	 */
	result = dns_message_create(mctx, DNS_MESSAGE_INTENTPARSE, &msg);
	ATF_CHECK_EQ_MSG(result, ISC_R_SUCCESS,
			 "dns_message_create: %s",
			 dns_result_totext(result));

	result = dns_message_settsigkey(msg, key);
	ATF_CHECK_EQ_MSG(result, ISC_R_SUCCESS,
			 "dns_message_settsigkey: %s",
			 dns_result_totext(result));

	result = dns_message_parse(msg, buf, 0);
	ATF_CHECK_EQ_MSG(result, ISC_R_SUCCESS,
			 "dns_message_parse: %s",
			 dns_result_totext(result));

	printmessage(msg);

	result = dns_message_setquerytsig(msg, querytsig);
	ATF_CHECK_EQ_MSG(result, ISC_R_SUCCESS,
			 "dns_message_setquerytsig: %s",
			 dns_result_totext(result));

	result = dns_tsig_verify(buf, msg, NULL, NULL);
	ATF_CHECK_EQ_MSG(result, ISC_R_SUCCESS,
			 "dns_tsig_verify: %s",
			 dns_result_totext(result));
	ATF_CHECK_EQ(msg->verified_sig, 1);
	ATF_CHECK_EQ(msg->tsigstatus, dns_rcode_noerror);

	/*
	 * Check that we have a TSIG in the first message.
	 */
	ATF_REQUIRE(dns_message_gettsig(msg, &tsigowner) != NULL);

	result = dns_message_getquerytsig(msg, mctx, &tsigin);
	ATF_CHECK_EQ_MSG(result, ISC_R_SUCCESS,
			 "dns_message_getquerytsig: %s",
			 dns_result_totext(result));

	tsigctx = msg->tsigctx;
	msg->tsigctx = NULL;
	isc_buffer_free(&buf);
	dns_message_destroy(&msg);

	result = dst_context_create3(key->key, mctx, DNS_LOGCATEGORY_DNSSEC,
				     ISC_FALSE, &outctx);
	ATF_REQUIRE_EQ(result, ISC_R_SUCCESS);

	/*
	 * Start digesting.
	 */
	result = add_mac(outctx, tsigout);
	ATF_REQUIRE_EQ(result, ISC_R_SUCCESS);

	/*
	 * Create response message 2.
	 */
	result = isc_buffer_allocate(mctx, &buf, 65535);
	ATF_REQUIRE_EQ(result, ISC_R_SUCCESS);

	ATF_REQUIRE_EQ(result, ISC_R_SUCCESS);
	render(buf, DNS_MESSAGEFLAG_QR, key, &tsigout, &tsigout, outctx);

	/*
	 * Process response message 2.
	 */
	result = dns_message_create(mctx, DNS_MESSAGE_INTENTPARSE, &msg);
	ATF_CHECK_EQ_MSG(result, ISC_R_SUCCESS,
			 "dns_message_create: %s",
			 dns_result_totext(result));

	msg->tcp_continuation = 1;
	msg->tsigctx = tsigctx;
	tsigctx = NULL;

	result = dns_message_settsigkey(msg, key);
	ATF_CHECK_EQ_MSG(result, ISC_R_SUCCESS,
			 "dns_message_settsigkey: %s",
			 dns_result_totext(result));

	result = dns_message_parse(msg, buf, 0);
	ATF_CHECK_EQ_MSG(result, ISC_R_SUCCESS,
			 "dns_message_parse: %s",
			 dns_result_totext(result));

	printmessage(msg);

	result = dns_message_setquerytsig(msg, tsigin);
	ATF_CHECK_EQ_MSG(result, ISC_R_SUCCESS,
			 "dns_message_setquerytsig: %s",
			 dns_result_totext(result));

	result = dns_tsig_verify(buf, msg, NULL, NULL);
	ATF_CHECK_EQ_MSG(result, ISC_R_SUCCESS,
			 "dns_tsig_verify: %s",
			 dns_result_totext(result));
	ATF_CHECK_EQ(msg->verified_sig, 1);
	ATF_CHECK_EQ(msg->tsigstatus, dns_rcode_noerror);

	/*
	 * Check that we don't have a TSIG in the second message.
	 */
	tsigowner = NULL;
	ATF_REQUIRE(dns_message_gettsig(msg, &tsigowner) == NULL);

	tsigctx = msg->tsigctx;
	msg->tsigctx = NULL;
	isc_buffer_free(&buf);
	dns_message_destroy(&msg);

	/*
	 * Create response message 3.
	 */
	result = isc_buffer_allocate(mctx, &buf, 65535);
	ATF_REQUIRE_EQ(result, ISC_R_SUCCESS);
	render(buf, DNS_MESSAGEFLAG_QR, key, &tsigout, &tsigout, outctx);

	result = add_tsig(outctx, key, buf);
	ATF_CHECK_EQ_MSG(result, ISC_R_SUCCESS,
			 "add_tsig: %s",
			 dns_result_totext(result));

	/*
	 * Process response message 3.
	 */
	result = dns_message_create(mctx, DNS_MESSAGE_INTENTPARSE, &msg);
	ATF_CHECK_EQ_MSG(result, ISC_R_SUCCESS,
			 "dns_message_create: %s",
			 dns_result_totext(result));

	msg->tcp_continuation = 1;
	msg->tsigctx = tsigctx;
	tsigctx = NULL;

	result = dns_message_settsigkey(msg, key);
	ATF_CHECK_EQ_MSG(result, ISC_R_SUCCESS,
			 "dns_message_settsigkey: %s",
			 dns_result_totext(result));

	result = dns_message_parse(msg, buf, 0);
	ATF_CHECK_EQ_MSG(result, ISC_R_SUCCESS,
			 "dns_message_parse: %s",
			 dns_result_totext(result));

	printmessage(msg);

	/*
	 * Check that we had a TSIG in the third message.
	 */
	ATF_REQUIRE(dns_message_gettsig(msg, &tsigowner) != NULL);

	result = dns_message_setquerytsig(msg, tsigin);
	ATF_CHECK_EQ_MSG(result, ISC_R_SUCCESS,
			 "dns_message_setquerytsig: %s",
			 dns_result_totext(result));

	result = dns_tsig_verify(buf, msg, NULL, NULL);
	ATF_CHECK_EQ_MSG(result, ISC_R_SUCCESS,
			 "dns_tsig_verify: %s",
			 dns_result_totext(result));
	ATF_CHECK_EQ(msg->verified_sig, 1);
	ATF_CHECK_EQ(msg->tsigstatus, dns_rcode_noerror);

	if (tsigin != NULL)
		isc_buffer_free(&tsigin);

	result = dns_message_getquerytsig(msg, mctx, &tsigin);
	ATF_CHECK_EQ_MSG(result, ISC_R_SUCCESS,
			 "dns_message_getquerytsig: %s",
			 dns_result_totext(result));

	isc_buffer_free(&buf);
	dns_message_destroy(&msg);

	if (outctx != NULL)
		dst_context_destroy(&outctx);
	if (querytsig != NULL)
		isc_buffer_free(&querytsig);
	if (tsigin != NULL)
		isc_buffer_free(&tsigin);
	if (tsigout != NULL)
		isc_buffer_free(&tsigout);
	if (buf != NULL)
		isc_buffer_free(&buf);
	if (msg != NULL)
		dns_message_destroy(&msg);
	if (key != NULL)
		dns_tsigkey_detach(&key);
	if (ring != NULL)
		dns_tsigkeyring_detach(&ring);
	dns_test_end();
}
Exemplo n.º 3
0
/*
 * Arrange to send as much as we can of "stream" without blocking.
 *
 * Requires:
 *	The stream iterator is initialized and points at an RR,
 *      or possibly at the end of the stream (that is, the
 *      _first method of the iterator has been called).
 */
static void
sendstream(xfrout_ctx_t *xfr) {
	dns_message_t *tcpmsg = NULL;
	dns_message_t *msg = NULL; /* Client message if UDP, tcpmsg if TCP */
	isc_result_t result;
	isc_region_t used;
	isc_region_t region;
	dns_rdataset_t *qrdataset;
	dns_name_t *msgname = NULL;
	dns_rdata_t *msgrdata = NULL;
	dns_rdatalist_t *msgrdl = NULL;
	dns_rdataset_t *msgrds = NULL;
	dns_compress_t cctx;
	isc_boolean_t cleanup_cctx = ISC_FALSE;
	isc_boolean_t is_tcp;

	int n_rrs;

	isc_buffer_clear(&xfr->buf);
	isc_buffer_clear(&xfr->txlenbuf);
	isc_buffer_clear(&xfr->txbuf);

	is_tcp = ISC_TF((xfr->client->attributes & NS_CLIENTATTR_TCP) != 0);
	if (!is_tcp) {
		/*
		 * In the UDP case, we put the response data directly into
		 * the client message.
		 */
		msg = xfr->client->message;
		CHECK(dns_message_reply(msg, ISC_TRUE));
	} else {
		/*
		 * TCP. Build a response dns_message_t, temporarily storing
		 * the raw, uncompressed owner names and RR data contiguously
		 * in xfr->buf.  We know that if the uncompressed data fits
		 * in xfr->buf, the compressed data will surely fit in a TCP
		 * message.
		 */

		CHECK(dns_message_create(xfr->mctx,
					 DNS_MESSAGE_INTENTRENDER, &tcpmsg));
		msg = tcpmsg;

		msg->id = xfr->id;
		msg->rcode = dns_rcode_noerror;
		msg->flags = DNS_MESSAGEFLAG_QR | DNS_MESSAGEFLAG_AA;
		if ((xfr->client->attributes & NS_CLIENTATTR_RA) != 0)
			msg->flags |= DNS_MESSAGEFLAG_RA;
		CHECK(dns_message_settsigkey(msg, xfr->tsigkey));
		CHECK(dns_message_setquerytsig(msg, xfr->lasttsig));
		if (xfr->lasttsig != NULL)
			isc_buffer_free(&xfr->lasttsig);

		/*
		 * Add a EDNS option to the message?
		 */
		if ((xfr->client->attributes & NS_CLIENTATTR_WANTOPT) != 0) {
			dns_rdataset_t *opt = NULL;

			CHECK(ns_client_addopt(xfr->client, msg, &opt));
			CHECK(dns_message_setopt(msg, opt));
			/*
			 * Add to first message only.
			 */
			xfr->client->attributes &= ~NS_CLIENTATTR_WANTNSID;
			xfr->client->attributes &= ~NS_CLIENTATTR_HAVEEXPIRE;
		}

		/*
		 * Account for reserved space.
		 */
		if (xfr->tsigkey != NULL)
			INSIST(msg->reserved != 0U);
		isc_buffer_add(&xfr->buf, msg->reserved);

		/*
		 * Include a question section in the first message only.
		 * BIND 8.2.1 will not recognize an IXFR if it does not
		 * have a question section.
		 */
		if (xfr->nmsg == 0) {
			dns_name_t *qname = NULL;
			isc_region_t r;

			/*
			 * Reserve space for the 12-byte message header
			 * and 4 bytes of question.
			 */
			isc_buffer_add(&xfr->buf, 12 + 4);

			qrdataset = NULL;
			result = dns_message_gettemprdataset(msg, &qrdataset);
			if (result != ISC_R_SUCCESS)
				goto failure;
			dns_rdataset_makequestion(qrdataset,
					xfr->client->message->rdclass,
					xfr->qtype);

			result = dns_message_gettempname(msg, &qname);
			if (result != ISC_R_SUCCESS)
				goto failure;
			dns_name_init(qname, NULL);
			isc_buffer_availableregion(&xfr->buf, &r);
			INSIST(r.length >= xfr->qname->length);
			r.length = xfr->qname->length;
			isc_buffer_putmem(&xfr->buf, xfr->qname->ndata,
					  xfr->qname->length);
			dns_name_fromregion(qname, &r);
			ISC_LIST_INIT(qname->list);
			ISC_LIST_APPEND(qname->list, qrdataset, link);

			dns_message_addname(msg, qname, DNS_SECTION_QUESTION);
		} else {
			/*
			 * Reserve space for the 12-byte message header
			 */
			isc_buffer_add(&xfr->buf, 12);
			msg->tcp_continuation = 1;
		}
	}

	/*
	 * Try to fit in as many RRs as possible, unless "one-answer"
	 * format has been requested.
	 */
	for (n_rrs = 0; ; n_rrs++) {
		dns_name_t *name = NULL;
		isc_uint32_t ttl;
		dns_rdata_t *rdata = NULL;

		unsigned int size;
		isc_region_t r;

		msgname = NULL;
		msgrdata = NULL;
		msgrdl = NULL;
		msgrds = NULL;

		xfr->stream->methods->current(xfr->stream,
					      &name, &ttl, &rdata);
		size = name->length + 10 + rdata->length;
		isc_buffer_availableregion(&xfr->buf, &r);
		if (size >= r.length) {
			/*
			 * RR would not fit.  If there are other RRs in the
			 * buffer, send them now and leave this RR to the
			 * next message.  If this RR overflows the buffer
			 * all by itself, fail.
			 *
			 * In theory some RRs might fit in a TCP message
			 * when compressed even if they do not fit when
			 * uncompressed, but surely we don't want
			 * to send such monstrosities to an unsuspecting
			 * slave.
			 */
			if (n_rrs == 0) {
				xfrout_log(xfr, ISC_LOG_WARNING,
					   "RR too large for zone transfer "
					   "(%d bytes)", size);
				/* XXX DNS_R_RRTOOLARGE? */
				result = ISC_R_NOSPACE;
				goto failure;
			}
			break;
		}

		if (isc_log_wouldlog(ns_g_lctx, XFROUT_RR_LOGLEVEL))
			log_rr(name, rdata, ttl); /* XXX */

		result = dns_message_gettempname(msg, &msgname);
		if (result != ISC_R_SUCCESS)
			goto failure;
		dns_name_init(msgname, NULL);
		isc_buffer_availableregion(&xfr->buf, &r);
		INSIST(r.length >= name->length);
		r.length = name->length;
		isc_buffer_putmem(&xfr->buf, name->ndata, name->length);
		dns_name_fromregion(msgname, &r);

		/* Reserve space for RR header. */
		isc_buffer_add(&xfr->buf, 10);

		result = dns_message_gettemprdata(msg, &msgrdata);
		if (result != ISC_R_SUCCESS)
			goto failure;
		isc_buffer_availableregion(&xfr->buf, &r);
		r.length = rdata->length;
		isc_buffer_putmem(&xfr->buf, rdata->data, rdata->length);
		dns_rdata_init(msgrdata);
		dns_rdata_fromregion(msgrdata,
				     rdata->rdclass, rdata->type, &r);

		result = dns_message_gettemprdatalist(msg, &msgrdl);
		if (result != ISC_R_SUCCESS)
			goto failure;
		msgrdl->type = rdata->type;
		msgrdl->rdclass = rdata->rdclass;
		msgrdl->ttl = ttl;
		if (rdata->type == dns_rdatatype_sig ||
		    rdata->type == dns_rdatatype_rrsig)
			msgrdl->covers = dns_rdata_covers(rdata);
		else
			msgrdl->covers = dns_rdatatype_none;
		ISC_LIST_APPEND(msgrdl->rdata, msgrdata, link);

		result = dns_message_gettemprdataset(msg, &msgrds);
		if (result != ISC_R_SUCCESS)
			goto failure;
		result = dns_rdatalist_tordataset(msgrdl, msgrds);
		INSIST(result == ISC_R_SUCCESS);

		ISC_LIST_APPEND(msgname->list, msgrds, link);

		dns_message_addname(msg, msgname, DNS_SECTION_ANSWER);
		msgname = NULL;

		result = xfr->stream->methods->next(xfr->stream);
		if (result == ISC_R_NOMORE) {
			xfr->end_of_stream = ISC_TRUE;
			break;
		}
		CHECK(result);

		if (! xfr->many_answers)
			break;
		/*
		 * At this stage, at least 1 RR has been rendered into
		 * the message. Check if we want to clamp this message
		 * here (TCP only). 20480 was set as an upper limit to
		 * improve message compression.
		 */
		if ((isc_buffer_usedlength(&xfr->buf) >= 20480) && is_tcp)
			break;
	}

	if (is_tcp) {
		CHECK(dns_compress_init(&cctx, -1, xfr->mctx));
		dns_compress_setsensitive(&cctx, ISC_TRUE);
		cleanup_cctx = ISC_TRUE;
		CHECK(dns_message_renderbegin(msg, &cctx, &xfr->txbuf));
		CHECK(dns_message_rendersection(msg, DNS_SECTION_QUESTION, 0));
		CHECK(dns_message_rendersection(msg, DNS_SECTION_ANSWER, 0));
		CHECK(dns_message_renderend(msg));
		dns_compress_invalidate(&cctx);
		cleanup_cctx = ISC_FALSE;

		isc_buffer_usedregion(&xfr->txbuf, &used);
		isc_buffer_putuint16(&xfr->txlenbuf,
				     (isc_uint16_t)used.length);
		region.base = xfr->txlenbuf.base;
		region.length = 2 + used.length;
		xfrout_log(xfr, ISC_LOG_DEBUG(8),
			   "sending TCP message of %d bytes",
			   used.length);
		CHECK(isc_socket_send(xfr->client->tcpsocket, /* XXX */
				      &region, xfr->client->task,
				      xfrout_senddone,
				      xfr));
		xfr->sends++;
	} else {
		xfrout_log(xfr, ISC_LOG_DEBUG(8), "sending IXFR UDP response");
		ns_client_send(xfr->client);
		xfr->stream->methods->pause(xfr->stream);
		xfrout_ctx_destroy(&xfr);
		return;
	}

	/* Advance lasttsig to be the last TSIG generated */
	CHECK(dns_message_getquerytsig(msg, xfr->mctx, &xfr->lasttsig));

	xfr->nmsg++;

 failure:
	if (msgname != NULL) {
		if (msgrds != NULL) {
			if (dns_rdataset_isassociated(msgrds))
				dns_rdataset_disassociate(msgrds);
			dns_message_puttemprdataset(msg, &msgrds);
		}
		if (msgrdl != NULL) {
			ISC_LIST_UNLINK(msgrdl->rdata, msgrdata, link);
			dns_message_puttemprdatalist(msg, &msgrdl);
		}
		if (msgrdata != NULL)
			dns_message_puttemprdata(msg, &msgrdata);
		dns_message_puttempname(msg, &msgname);
	}

	if (tcpmsg != NULL)
		dns_message_destroy(&tcpmsg);

	if (cleanup_cctx)
		dns_compress_invalidate(&cctx);
	/*
	 * Make sure to release any locks held by database
	 * iterators before returning from the event handler.
	 */
	xfr->stream->methods->pause(xfr->stream);

	if (result == ISC_R_SUCCESS)
		return;

	xfrout_fail(xfr, result, "sending zone data");
}
Exemplo n.º 4
0
static void
render(isc_buffer_t *buf, unsigned flags, dns_tsigkey_t *key,
       isc_buffer_t **tsigin, isc_buffer_t **tsigout,
       dst_context_t *tsigctx)
{
	dns_message_t *msg = NULL;
	dns_compress_t cctx;
	isc_result_t result;

	result = dns_message_create(mctx, DNS_MESSAGE_INTENTRENDER, &msg);
	ATF_CHECK_EQ_MSG(result, ISC_R_SUCCESS,
			 "dns_message_create: %s",
			 dns_result_totext(result));

	msg->id = 50;
	msg->rcode = dns_rcode_noerror;
	msg->flags = flags;

	if (tsigin == tsigout)
		msg->tcp_continuation = 1;

	if (tsigctx == NULL) {
		result = dns_message_settsigkey(msg, key);
		ATF_CHECK_EQ_MSG(result, ISC_R_SUCCESS,
				 "dns_message_settsigkey: %s",
				 dns_result_totext(result));

		result = dns_message_setquerytsig(msg, *tsigin);
		ATF_CHECK_EQ_MSG(result, ISC_R_SUCCESS,
				 "dns_message_setquerytsig: %s",
				 dns_result_totext(result));
	}

	result = dns_compress_init(&cctx, -1, mctx);
	ATF_CHECK_EQ_MSG(result, ISC_R_SUCCESS,
			 "dns_compress_init: %s",
			 dns_result_totext(result));

	result = dns_message_renderbegin(msg, &cctx, buf);
	ATF_CHECK_EQ_MSG(result, ISC_R_SUCCESS,
			 "dns_message_renderbegin: %s",
			 dns_result_totext(result));

	result = dns_message_renderend(msg);
	ATF_CHECK_EQ_MSG(result, ISC_R_SUCCESS,
			 "dns_message_renderend: %s",
			 dns_result_totext(result));

	if (tsigctx != NULL) {
		isc_region_t r;

		isc_buffer_usedregion(buf, &r);
		result = dst_context_adddata(tsigctx, &r);
	} else {
		if (tsigin == tsigout && *tsigin != NULL)
			isc_buffer_free(tsigin);

		result = dns_message_getquerytsig(msg, mctx, tsigout);
		ATF_CHECK_EQ_MSG(result, ISC_R_SUCCESS,
				 "dns_message_getquerytsig: %s",
				 dns_result_totext(result));
	}

	dns_compress_invalidate(&cctx);
	dns_message_destroy(&msg);
}