Complete rewrite the BIND 9 build system

The rewrite of BIND 9 build system is a large work and cannot be reasonable split into separate merge requests. Addition of the automake has a positive effect on the readability and maintainability of the build system as it is more declarative, it allows conditional and we are able to drop all of the custom make code that BIND 9 developed over the years to overcome the deficiencies of autoconf + custom Makefile.in files. This squashed commit contains following changes: - conversion (or rather fresh rewrite) of all Makefile.in files to Makefile.am by using automake - the libtool is now properly integrated with automake (the way we used it was rather hackish as the only official way how to use libtool is via automake - the dynamic module loading was rewritten from a custom patchwork to libtool's libltdl (which includes the patchwork to support module loading on different systems internally) - conversion of the unit test executor from kyua to automake parallel driver - conversion of the system test executor from custom make/shell to automake parallel driver - The GSSAPI has been refactored, the custom SPNEGO on the basis that all major KRB5/GSSAPI (mit-krb5, heimdal and Windows) implementations support SPNEGO mechanism. - The various defunct tests from bin/tests have been removed: bin/tests/optional and bin/tests/pkcs11 - The text files generated from the MD files have been removed, the MarkDown has been designed to be readable by both humans and computers - The xsl header is now generated by a simple sed command instead of perl helper - The <irs/platform.h> header has been removed - cleanups of configure.ac script to make it more simpler, addition of multiple macros (there's still work to be done though) - the tarball can now be prepared with `make dist` - the system tests are partially able to run in oot build Here's a list of unfinished work that needs to be completed in subsequent merge requests: - `make distcheck` doesn't yet work (because of system tests oot run is not yet finished) - documentation is not yet built, there's a different merge request with docbook to sphinx-build rst conversion that needs to be rebased and adapted on top of the automake - msvc build is non functional yet and we need to decide whether we will just cross-compile bind9 using mingw-w64 or fix the msvc build - contributed dlz modules are not included neither in the autoconf nor automake
2018-08-07 16:46:53 +02:00
parent 4df5a5832c
commit 978c7b2e89
596 changed files with 4301 additions and 21770 deletions
--- a/bin/tests/system/dlzexternal/driver/driver.c
+++ b/bin/tests/system/dlzexternal/driver/driver.c
@@ -0,0 +1,863 @@
+/*
+ * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ *
+ * 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 http://mozilla.org/MPL/2.0/.
+ *
+ * See the COPYRIGHT file distributed with this work for additional
+ * information regarding copyright ownership.
+ */
+
+/*
+ * This provides a very simple example of an external loadable DLZ
+ * driver, with update support.
+ */
+
+#include "driver.h"
+#include <inttypes.h>
+#include <stdarg.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+#include <isc/log.h>
+#include <isc/result.h>
+#include <isc/string.h>
+#include <isc/types.h>
+#include <isc/util.h>
+
+#include <dns/dlz_dlopen.h>
+#include <dns/types.h>
+
+/* aliases for exported symbols */
+
+#define dlz_version	 dlzexternal_LTX_dlz_version
+#define dlz_create	 dlzexternal_LTX_dlz_create
+#define dlz_destroy	 dlzexternal_LTX_dlz_destroy
+#define dlz_findzonedb	 dlzexternal_LTX_dlz_findzonedb
+#define dlz_lookup	 dlzexternal_LTX_dlz_lookup
+#define dlz_allowzonexfr dlzexternal_LTX_dlz_allowzonexfr
+#define dlz_allnodes	 dlzexternal_LTX_dlz_allnodes
+#define dlz_newversion	 dlzexternal_LTX_dlz_newversion
+#define dlz_closeversion dlzexternal_LTX_dlz_closeversion
+#define dlz_configure	 dlzexternal_LTX_dlz_configure
+#define dlz_ssumatch	 dlzexternal_LTX_dlz_ssumatch
+#define dlz_addrdataset	 dlzexternal_LTX_dlz_addrdataset
+#define dlz_sbrdataset	 dlzexternal_LTX_dlz_sbrdataset
+#define dlz_delrdataset	 dlzexternal_LTX_dlz_delrdataset
+
+dlz_dlopen_version_t dlz_version;
+dlz_dlopen_create_t dlz_create;
+dlz_dlopen_destroy_t dlz_destroy;
+dlz_dlopen_findzonedb_t dlz_findzonedb;
+dlz_dlopen_lookup_t dlz_lookup;
+dlz_dlopen_allowzonexfr_t dlz_allowzonexfr;
+dlz_dlopen_allnodes_t dlz_allnodes;
+dlz_dlopen_newversion_t dlz_newversion;
+dlz_dlopen_closeversion_t dlz_closeversion;
+dlz_dlopen_configure_t dlz_configure;
+dlz_dlopen_ssumatch_t dlz_ssumatch;
+dlz_dlopen_addrdataset_t dlz_addrdataset;
+dlz_dlopen_subrdataset_t dlz_subrdataset;
+dlz_dlopen_delrdataset_t dlz_delrdataset;
+
+#define CHECK(x)                             \
+	do {                                 \
+		result = (x);                \
+		if (result != ISC_R_SUCCESS) \
+			goto failure;        \
+	} while (0)
+
+#define loginfo(...)                                           \
+	({                                                     \
+		if ((state != NULL) && (state->log != NULL))   \
+			state->log(ISC_LOG_INFO, __VA_ARGS__); \
+	})
+#define logerr(...)                                             \
+	({                                                      \
+		if ((state != NULL) && (state->log != NULL))    \
+			state->log(ISC_LOG_ERROR, __VA_ARGS__); \
+	})
+
+/* For this simple example, use fixed sized strings */
+struct record {
+	char name[100];
+	char type[10];
+	char data[200];
+	dns_ttl_t ttl;
+};
+
+#define MAX_RECORDS 100
+
+typedef void
+log_t(int level, const char *fmt, ...);
+
+struct dlz_example_data {
+	char *zone_name;
+
+	/* An example driver doesn't need good memory management :-) */
+	struct record current[MAX_RECORDS];
+	struct record adds[MAX_RECORDS];
+	struct record deletes[MAX_RECORDS];
+
+	bool transaction_started;
+
+	/* Helper functions from the dlz_dlopen driver */
+	log_t *log;
+	dns_sdlz_putrr_t *putrr;
+	dns_sdlz_putnamedrr_t *putnamedrr;
+	dns_dlz_writeablezone_t *writeable_zone;
+};
+
+static bool
+single_valued(const char *type) {
+	const char *single[] = { "soa", "cname", NULL };
+	int i;
+
+	for (i = 0; single[i]; i++) {
+		if (strcasecmp(single[i], type) == 0) {
+			return (true);
+		}
+	}
+	return (false);
+}
+
+/*
+ * Add a record to a list
+ */
+static isc_result_t
+add_name(struct dlz_example_data *state, struct record *list, const char *name,
+	 const char *type, dns_ttl_t ttl, const char *data) {
+	int i;
+	bool single = single_valued(type);
+	int first_empty = -1;
+
+	for (i = 0; i < MAX_RECORDS; i++) {
+		INSIST(list[i].name != NULL);
+		if (first_empty == -1 && strlen(list[i].name) == 0U) {
+			first_empty = i;
+		}
+		if (strcasecmp(list[i].name, name) != 0) {
+			continue;
+		}
+		if (strcasecmp(list[i].type, type) != 0) {
+			continue;
+		}
+		if (!single && strcasecmp(list[i].data, data) != 0) {
+			continue;
+		}
+		break;
+	}
+	if (i == MAX_RECORDS && first_empty != -1) {
+		i = first_empty;
+	}
+	if (i == MAX_RECORDS) {
+		logerr("dlz_example: out of record space");
+		return (ISC_R_FAILURE);
+	}
+
+	if (strlen(name) >= sizeof(list[i].name) ||
+	    strlen(type) >= sizeof(list[i].type) ||
+	    strlen(data) >= sizeof(list[i].data))
+	{
+		return (ISC_R_NOSPACE);
+	}
+
+	strncpy(list[i].name, name, sizeof(list[i].name) - 1);
+	list[i].name[sizeof(list[i].name) - 1] = '\0';
+
+	strncpy(list[i].type, type, sizeof(list[i].type) - 1);
+	list[i].type[sizeof(list[i].type) - 1] = '\0';
+
+	strncpy(list[i].data, data, sizeof(list[i].data) - 1);
+	list[i].data[sizeof(list[i].data) - 1] = '\0';
+
+	list[i].ttl = ttl;
+
+	return (ISC_R_SUCCESS);
+}
+
+/*
+ * Delete a record from a list
+ */
+static isc_result_t
+del_name(struct dlz_example_data *state, struct record *list, const char *name,
+	 const char *type, dns_ttl_t ttl, const char *data) {
+	int i;
+
+	UNUSED(state);
+
+	for (i = 0; i < MAX_RECORDS; i++) {
+		if (strcasecmp(name, list[i].name) == 0 &&
+		    strcasecmp(type, list[i].type) == 0 &&
+		    strcasecmp(data, list[i].data) == 0 && ttl == list[i].ttl)
+		{
+			break;
+		}
+	}
+	if (i == MAX_RECORDS) {
+		return (ISC_R_NOTFOUND);
+	}
+	memset(&list[i], 0, sizeof(struct record));
+	return (ISC_R_SUCCESS);
+}
+
+static isc_result_t
+fmt_address(isc_sockaddr_t *addr, char *buffer, size_t size) {
+	char addr_buf[INET6_ADDRSTRLEN];
+	const char *ret;
+	uint16_t port = 0;
+
+	switch (addr->type.sa.sa_family) {
+	case AF_INET:
+		port = ntohs(addr->type.sin.sin_port);
+		ret = inet_ntop(AF_INET, &addr->type.sin.sin_addr, addr_buf,
+				sizeof(addr_buf));
+		break;
+	case AF_INET6:
+		port = ntohs(addr->type.sin6.sin6_port);
+		ret = inet_ntop(AF_INET6, &addr->type.sin6.sin6_addr, addr_buf,
+				sizeof(addr_buf));
+		break;
+	default:
+		return (ISC_R_FAILURE);
+	}
+
+	if (ret == NULL) {
+		return (ISC_R_FAILURE);
+	}
+
+	snprintf(buffer, size, "%s#%u", addr_buf, port);
+	return (ISC_R_SUCCESS);
+}
+
+/*
+ * Return the version of the API
+ */
+int
+dlz_version(unsigned int *flags) {
+	UNUSED(flags);
+	return (DLZ_DLOPEN_VERSION);
+}
+
+/*
+ * Remember a helper function from the bind9 dlz_dlopen driver
+ */
+static void
+b9_add_helper(struct dlz_example_data *state, const char *helper_name,
+	      void *ptr) {
+	if (strcmp(helper_name, "log") == 0) {
+		state->log = (log_t *)ptr;
+	}
+	if (strcmp(helper_name, "putrr") == 0) {
+		state->putrr = (dns_sdlz_putrr_t *)ptr;
+	}
+	if (strcmp(helper_name, "putnamedrr") == 0) {
+		state->putnamedrr = (dns_sdlz_putnamedrr_t *)ptr;
+	}
+	if (strcmp(helper_name, "writeable_zone") == 0) {
+		state->writeable_zone = (dns_dlz_writeablezone_t *)ptr;
+	}
+}
+
+/*
+ * Called to initialize the driver
+ */
+isc_result_t
+dlz_create(const char *dlzname, unsigned int argc, char *argv[], void **dbdata,
+	   ...) {
+	struct dlz_example_data *state;
+	const char *helper_name;
+	va_list ap;
+	char soa_data[1024];
+	const char *extra;
+	isc_result_t result;
+	int n;
+
+	UNUSED(dlzname);
+
+	state = calloc(1, sizeof(struct dlz_example_data));
+	if (state == NULL) {
+		return (ISC_R_NOMEMORY);
+	}
+
+	/* Fill in the helper functions */
+	va_start(ap, dbdata);
+	while ((helper_name = va_arg(ap, const char *)) != NULL) {
+		b9_add_helper(state, helper_name, va_arg(ap, void *));
+	}
+	va_end(ap);
+
+	if (argc < 2 || argv[1][0] == '\0') {
+		logerr("dlz_example: please specify a zone name");
+		dlz_destroy(state);
+		return (ISC_R_FAILURE);
+	}
+
+	/* Ensure zone name is absolute */
+	state->zone_name = malloc(strlen(argv[1]) + 2);
+	if (state->zone_name == NULL) {
+		free(state);
+		return (ISC_R_NOMEMORY);
+	}
+	if (argv[1][strlen(argv[1]) - 1] == '.') {
+		strcpy(state->zone_name, argv[1]);
+	} else {
+		sprintf(state->zone_name, "%s.", argv[1]);
+	}
+
+	if (strcmp(state->zone_name, ".") == 0) {
+		extra = ".root";
+	} else {
+		extra = ".";
+	}
+
+	n = sprintf(soa_data, "%s hostmaster%s%s 123 900 600 86400 3600",
+		    state->zone_name, extra, state->zone_name);
+
+	if (n < 0) {
+		CHECK(ISC_R_FAILURE);
+	}
+	if ((unsigned)n >= sizeof(soa_data)) {
+		CHECK(ISC_R_NOSPACE);
+	}
+
+	add_name(state, &state->current[0], state->zone_name, "soa", 3600,
+		 soa_data);
+	add_name(state, &state->current[0], state->zone_name, "ns", 3600,
+		 state->zone_name);
+	add_name(state, &state->current[0], state->zone_name, "a", 1800,
+		 "10.53.0.1");
+
+	loginfo("dlz_example: started for zone %s", state->zone_name);
+
+	*dbdata = state;
+	return (ISC_R_SUCCESS);
+
+failure:
+	free(state);
+	return (result);
+}
+
+/*
+ * Shut down the backend
+ */
+void
+dlz_destroy(void *dbdata) {
+	struct dlz_example_data *state = (struct dlz_example_data *)dbdata;
+
+	loginfo("dlz_example: shutting down zone %s", state->zone_name);
+	free(state->zone_name);
+	free(state);
+}
+
+/*
+ * See if we handle a given zone
+ */
+isc_result_t
+dlz_findzonedb(void *dbdata, const char *name, dns_clientinfomethods_t *methods,
+	       dns_clientinfo_t *clientinfo) {
+	struct dlz_example_data *state = (struct dlz_example_data *)dbdata;
+	isc_sockaddr_t *src;
+	char addrbuf[100];
+	char absolute[1024];
+
+	strcpy(addrbuf, "unknown");
+	if (methods != NULL && methods->sourceip != NULL &&
+	    methods->version - methods->age <= DNS_CLIENTINFOMETHODS_VERSION &&
+	    DNS_CLIENTINFOMETHODS_VERSION <= methods->version)
+	{
+		methods->sourceip(clientinfo, &src);
+		fmt_address(src, addrbuf, sizeof(addrbuf));
+	}
+
+	loginfo("dlz_example: dlz_findzonedb called with name '%s' "
+		"in zone DB '%s' from %s",
+		name, state->zone_name, addrbuf);
+
+	/*
+	 * Returning ISC_R_NOTFOUND will cause the query logic to
+	 * check the database for parent names, looking for zone cuts.
+	 *
+	 * Returning ISC_R_NOMORE prevents the query logic from doing
+	 * this; it will move onto the next database after a single query.
+	 */
+	if (strcasecmp(name, "test.example.com") == 0) {
+		return (ISC_R_NOMORE);
+	}
+
+	/*
+	 * For example.net, only return ISC_R_NOMORE when queried
+	 * from 10.53.0.1.
+	 */
+	if (strcasecmp(name, "test.example.net") == 0 &&
+	    strncmp(addrbuf, "10.53.0.1", 9) == 0)
+	{
+		return (ISC_R_NOMORE);
+	}
+
+	/*
+	 * For bigcname.domain, return success so it appears to be
+	 * the zone origin; this regression tests a bug in which
+	 * zone origin nodes could fail to return SERVFAIL to the client.
+	 */
+	if (strcasecmp(name, "bigcname.domain") == 0) {
+		return (ISC_R_SUCCESS);
+	}
+
+	/*
+	 * Return success if we have an exact match between the
+	 * zone name and the qname
+	 */
+	if (strcasecmp(state->zone_name, name) == 0) {
+		return (ISC_R_SUCCESS);
+	}
+
+	snprintf(absolute, sizeof(absolute), "%s.", name);
+	if (strcasecmp(state->zone_name, absolute) == 0) {
+		return (ISC_R_SUCCESS);
+	}
+
+	return (ISC_R_NOTFOUND);
+}
+
+/*
+ * Look up one record in the sample database.
+ *
+ * If the queryname is "source-addr", send back a TXT record containing
+ * the address of the client, to test the use of 'methods' and 'clientinfo'
+ *
+ * If the queryname is "too-long", send back a TXT record that's too long
+ * to process; this should result in a SERVFAIL when queried.
+ */
+isc_result_t
+dlz_lookup(const char *zone, const char *name, void *dbdata,
+	   dns_sdlzlookup_t *lookup, dns_clientinfomethods_t *methods,
+	   dns_clientinfo_t *clientinfo) {
+	isc_result_t result;
+	struct dlz_example_data *state = (struct dlz_example_data *)dbdata;
+	bool found = false;
+	void *dbversion = NULL;
+	isc_sockaddr_t *src;
+	char full_name[256];
+	char buf[512];
+	static char last[256];
+	static int count = 0;
+	int i, size;
+
+	UNUSED(zone);
+
+	if (state->putrr == NULL) {
+		return (ISC_R_NOTIMPLEMENTED);
+	}
+
+	if (strcmp(name, "@") == 0) {
+		size = snprintf(full_name, sizeof(full_name), "%s",
+				state->zone_name);
+	} else if (strcmp(state->zone_name, ".") == 0) {
+		size = snprintf(full_name, sizeof(full_name), "%s.", name);
+	} else {
+		size = snprintf(full_name, sizeof(full_name), "%s.%s", name,
+				state->zone_name);
+	}
+
+	if (size < 0 || (size_t)size >= sizeof(full_name) ||
+	    (size_t)size >= sizeof(last))
+	{
+		return (ISC_R_NOSPACE);
+	}
+
+	/*
+	 * For test purposes, log all calls to dlz_lookup()
+	 */
+	if (strcasecmp(full_name, last) == 0) {
+		count++;
+	} else {
+		count = 1;
+		memcpy(last, full_name, size + 1);
+	}
+	loginfo("lookup #%d for %s", count, full_name);
+
+	/*
+	 * If we need to know the database version (as set in
+	 * the 'newversion' dlz function) we can pick it up from the
+	 * clientinfo.
+	 *
+	 * This allows a lookup to query the correct version of the DNS
+	 * data, if the DLZ can differentiate between versions.
+	 *
+	 * For example, if a new database transaction is created by
+	 * 'newversion', the lookup should query within the same
+	 * transaction scope if it can.
+	 *
+	 * If the DLZ only operates on 'live' data, then version
+	 * wouldn't necessarily be needed.
+	 */
+	if (clientinfo != NULL && clientinfo->version >= DNS_CLIENTINFO_VERSION)
+	{
+		dbversion = clientinfo->dbversion;
+		if (dbversion != NULL && *(bool *)dbversion) {
+			loginfo("dlz_example: lookup against live transaction");
+		}
+	}
+
+	if (strcmp(name, "source-addr") == 0) {
+		strncpy(buf, "unknown", sizeof(buf));
+		if (methods != NULL && methods->sourceip != NULL &&
+		    (methods->version - methods->age <=
+		     DNS_CLIENTINFOMETHODS_VERSION) &&
+		    DNS_CLIENTINFOMETHODS_VERSION <= methods->version)
+		{
+			methods->sourceip(clientinfo, &src);
+			fmt_address(src, buf, sizeof(buf));
+		}
+
+		loginfo("dlz_example: lookup connection from %s", buf);
+
+		found = true;
+		result = state->putrr(lookup, "TXT", 0, buf);
+		if (result != ISC_R_SUCCESS) {
+			return (result);
+		}
+	}
+
+	if (strcmp(name, "too-long") == 0 ||
+	    strcmp(zone, "bigcname.domain") == 0) {
+		for (i = 0; i < 511; i++) {
+			buf[i] = 'x';
+		}
+		buf[i] = '\0';
+		found = true;
+		result = state->putrr(lookup, "TXT", 0, buf);
+		if (result != ISC_R_SUCCESS) {
+			return (result);
+		}
+	}
+
+	/* Tests for DLZ redirection zones */
+	if (strcmp(name, "*") == 0 && strcmp(zone, ".") == 0) {
+		result = state->putrr(lookup, "A", 0, "100.100.100.2");
+		found = true;
+		if (result != ISC_R_SUCCESS) {
+			return (result);
+		}
+	}
+
+	if (strcmp(name, "long.name.is.not.there") == 0 &&
+	    strcmp(zone, ".") == 0) {
+		result = state->putrr(lookup, "A", 0, "100.100.100.3");
+		found = true;
+		if (result != ISC_R_SUCCESS) {
+			return (result);
+		}
+	}
+
+	/* Answer from current records */
+	for (i = 0; i < MAX_RECORDS; i++) {
+		if (strcasecmp(state->current[i].name, full_name) == 0) {
+			found = true;
+			result = state->putrr(lookup, state->current[i].type,
+					      state->current[i].ttl,
+					      state->current[i].data);
+			if (result != ISC_R_SUCCESS) {
+				return (result);
+			}
+		}
+	}
+
+	if (!found) {
+		return (ISC_R_NOTFOUND);
+	}
+
+	return (ISC_R_SUCCESS);
+}
+
+/*
+ * See if a zone transfer is allowed
+ */
+isc_result_t
+dlz_allowzonexfr(void *dbdata, const char *name, const char *client) {
+	struct dlz_example_data *state = (struct dlz_example_data *)dbdata;
+	isc_result_t result;
+
+	loginfo("dlz_example: dlz_allowzonexfr called for %s", name);
+
+	result = dlz_findzonedb(dbdata, name, NULL, NULL);
+	if (result != ISC_R_SUCCESS) {
+		loginfo("dlz_example: findzonedb returned %s",
+			isc_result_totext(result));
+		return (result);
+	}
+
+	/*
+	 * Exception for "example.org" so we can test the use of
+	 * the view ACL.
+	 */
+	if (strcmp(name, "example.org") == 0) {
+		loginfo("dlz_example: use view ACL for example.org");
+		return (ISC_R_DEFAULT);
+	}
+
+	/*
+	 * Exception for 10.53.0.5 so we can test that allow-transfer
+	 * is effective.
+	 */
+	if (strcmp(client, "10.53.0.5") == 0) {
+		loginfo("dlz_example: disallow transfer to 10.53.0.5");
+		return (ISC_R_NOPERM);
+	}
+
+	loginfo("dlz_example: transfer allowed for %s", name);
+
+	return (ISC_R_SUCCESS);
+}
+
+/*
+ * Perform a zone transfer
+ */
+isc_result_t
+dlz_allnodes(const char *zone, void *dbdata, dns_sdlzallnodes_t *allnodes) {
+	struct dlz_example_data *state = (struct dlz_example_data *)dbdata;
+	int i;
+
+	UNUSED(zone);
+
+	if (state->putnamedrr == NULL) {
+		return (ISC_R_NOTIMPLEMENTED);
+	}
+
+	for (i = 0; i < MAX_RECORDS; i++) {
+		isc_result_t result;
+		if (strlen(state->current[i].name) == 0U) {
+			continue;
+		}
+		result = state->putnamedrr(allnodes, state->current[i].name,
+					   state->current[i].type,
+					   state->current[i].ttl,
+					   state->current[i].data);
+		if (result != ISC_R_SUCCESS) {
+			return (result);
+		}
+	}
+
+	return (ISC_R_SUCCESS);
+}
+
+/*
+ * Start a transaction
+ */
+isc_result_t
+dlz_newversion(const char *zone, void *dbdata, void **versionp) {
+	struct dlz_example_data *state = (struct dlz_example_data *)dbdata;
+
+	if (state->transaction_started) {
+		loginfo("dlz_example: transaction already started for zone %s",
+			zone);
+		return (ISC_R_FAILURE);
+	}
+
+	state->transaction_started = true;
+	*versionp = (void *)&state->transaction_started;
+
+	return (ISC_R_SUCCESS);
+}
+
+/*
+ * End a transaction
+ */
+void
+dlz_closeversion(const char *zone, bool commit, void *dbdata, void **versionp) {
+	struct dlz_example_data *state = (struct dlz_example_data *)dbdata;
+
+	if (!state->transaction_started) {
+		loginfo("dlz_example: transaction not started for zone %s",
+			zone);
+		*versionp = NULL;
+		return;
+	}
+
+	state->transaction_started = false;
+
+	*versionp = NULL;
+
+	if (commit) {
+		int i;
+		loginfo("dlz_example: committing transaction on zone %s", zone);
+		for (i = 0; i < MAX_RECORDS; i++) {
+			if (strlen(state->deletes[i].name) > 0U) {
+				(void)del_name(state, &state->current[0],
+					       state->deletes[i].name,
+					       state->deletes[i].type,
+					       state->deletes[i].ttl,
+					       state->deletes[i].data);
+			}
+		}
+		for (i = 0; i < MAX_RECORDS; i++) {
+			if (strlen(state->adds[i].name) > 0U) {
+				(void)add_name(state, &state->current[0],
+					       state->adds[i].name,
+					       state->adds[i].type,
+					       state->adds[i].ttl,
+					       state->adds[i].data);
+			}
+		}
+	} else {
+		loginfo("dlz_example: cancelling transaction on zone %s", zone);
+	}
+	memset(state->adds, 0, sizeof(state->adds));
+	memset(state->deletes, 0, sizeof(state->deletes));
+}
+
+/*
+ * Configure a writeable zone
+ */
+isc_result_t
+dlz_configure(dns_view_t *view, dns_dlzdb_t *dlzdb, void *dbdata) {
+	struct dlz_example_data *state = (struct dlz_example_data *)dbdata;
+	isc_result_t result;
+
+	loginfo("dlz_example: starting configure");
+
+	if (state->writeable_zone == NULL) {
+		loginfo("dlz_example: no writeable_zone method available");
+		return (ISC_R_FAILURE);
+	}
+
+	result = state->writeable_zone(view, dlzdb, state->zone_name);
+	if (result != ISC_R_SUCCESS) {
+		loginfo("dlz_example: failed to configure zone %s",
+			state->zone_name);
+		return (result);
+	}
+
+	loginfo("dlz_example: configured writeable zone %s", state->zone_name);
+	return (ISC_R_SUCCESS);
+}
+
+/*
+ * Authorize a zone update
+ */
+bool
+dlz_ssumatch(const char *signer, const char *name, const char *tcpaddr,
+	     const char *type, const char *key, uint32_t keydatalen,
+	     unsigned char *keydata, void *dbdata) {
+	struct dlz_example_data *state = (struct dlz_example_data *)dbdata;
+
+	UNUSED(tcpaddr);
+	UNUSED(type);
+	UNUSED(key);
+	UNUSED(keydatalen);
+	UNUSED(keydata);
+
+	if (strncmp(name, "deny.", 5) == 0) {
+		loginfo("dlz_example: denying update of name=%s by %s", name,
+			signer);
+		return (false);
+	}
+	loginfo("dlz_example: allowing update of name=%s by %s", name, signer);
+	return (true);
+}
+
+static isc_result_t
+modrdataset(struct dlz_example_data *state, const char *name,
+	    const char *rdatastr, struct record *list) {
+	char *full_name, *dclass, *type, *data, *ttlstr, *buf;
+	char absolute[1024];
+	isc_result_t result;
+	char *saveptr = NULL;
+
+	buf = strdup(rdatastr);
+	if (buf == NULL) {
+		return (ISC_R_FAILURE);
+	}
+
+	/*
+	 * The format is:
+	 * FULLNAME\tTTL\tDCLASS\tTYPE\tDATA
+	 *
+	 * The DATA field is space separated, and is in the data format
+	 * for the type used by dig
+	 */
+
+	full_name = strtok_r(buf, "\t", &saveptr);
+	if (full_name == NULL) {
+		goto error;
+	}
+
+	ttlstr = strtok_r(NULL, "\t", &saveptr);
+	if (ttlstr == NULL) {
+		goto error;
+	}
+
+	dclass = strtok_r(NULL, "\t", &saveptr);
+	if (dclass == NULL) {
+		goto error;
+	}
+
+	type = strtok_r(NULL, "\t", &saveptr);
+	if (type == NULL) {
+		goto error;
+	}
+
+	data = strtok_r(NULL, "\t", &saveptr);
+	if (data == NULL) {
+		goto error;
+	}
+
+	if (name[strlen(name) - 1] != '.') {
+		snprintf(absolute, sizeof(absolute), "%s.", name);
+		name = absolute;
+	}
+
+	result = add_name(state, list, name, type, strtoul(ttlstr, NULL, 10),
+			  data);
+	free(buf);
+	return (result);
+
+error:
+	free(buf);
+	return (ISC_R_FAILURE);
+}
+
+isc_result_t
+dlz_addrdataset(const char *name, const char *rdatastr, void *dbdata,
+		void *version) {
+	struct dlz_example_data *state = (struct dlz_example_data *)dbdata;
+
+	if (version != (void *)&state->transaction_started) {
+		return (ISC_R_FAILURE);
+	}
+
+	loginfo("dlz_example: adding rdataset %s '%s'", name, rdatastr);
+
+	return (modrdataset(state, name, rdatastr, &state->adds[0]));
+}
+
+isc_result_t
+dlz_subrdataset(const char *name, const char *rdatastr, void *dbdata,
+		void *version) {
+	struct dlz_example_data *state = (struct dlz_example_data *)dbdata;
+
+	if (version != (void *)&state->transaction_started) {
+		return (ISC_R_FAILURE);
+	}
+
+	loginfo("dlz_example: subtracting rdataset %s '%s'", name, rdatastr);
+
+	return (modrdataset(state, name, rdatastr, &state->deletes[0]));
+}
+
+isc_result_t
+dlz_delrdataset(const char *name, const char *type, void *dbdata,
+		void *version) {
+	struct dlz_example_data *state = (struct dlz_example_data *)dbdata;
+
+	if (version != (void *)&state->transaction_started) {
+		return (ISC_R_FAILURE);
+	}
+
+	loginfo("dlz_example: deleting rdataset %s of type %s", name, type);
+
+	return (ISC_R_SUCCESS);
+}