1 files changed, 601 insertions, 0 deletions
diff --git a/lib/dns/zt.c b/lib/dns/zt.c
new file mode 100644
index 0000000..c84da2f
--- /dev/null
+++ b/lib/dns/zt.c
@@ -0,0 +1,601 @@
+/*
+ * 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.
+ */
+
+
+/*! \file */
+
+#include <config.h>
+
+#include <inttypes.h>
+#include <stdbool.h>
+
+#include <isc/file.h>
+#include <isc/magic.h>
+#include <isc/mem.h>
+#include <isc/string.h>
+#include <isc/task.h>
+#include <isc/util.h>
+
+#include <dns/log.h>
+#include <dns/name.h>
+#include <dns/rbt.h>
+#include <dns/rdataclass.h>
+#include <dns/result.h>
+#include <dns/view.h>
+#include <dns/zone.h>
+#include <dns/zt.h>
+
+struct dns_zt {
+	/* Unlocked. */
+	unsigned int		magic;
+	isc_mem_t		*mctx;
+	dns_rdataclass_t	rdclass;
+	isc_rwlock_t		rwlock;
+	dns_zt_allloaded_t	loaddone;
+	void *			loaddone_arg;
+	/* Locked by lock. */
+	bool		flush;
+	uint32_t		references;
+	unsigned int		loads_pending;
+	dns_rbt_t		*table;
+};
+
+#define ZTMAGIC			ISC_MAGIC('Z', 'T', 'b', 'l')
+#define VALID_ZT(zt) 		ISC_MAGIC_VALID(zt, ZTMAGIC)
+
+struct zt_load_params {
+	dns_zt_zoneloaded_t dl;
+	bool newonly;
+	struct dns_zt* zt;
+};
+
+static void
+auto_detach(void *, void *);
+
+static isc_result_t
+load(dns_zone_t *zone, void *uap);
+
+static isc_result_t
+asyncload(dns_zone_t *zone, void *callback);
+
+static isc_result_t
+loadnew(dns_zone_t *zone, void *uap);
+
+static isc_result_t
+freezezones(dns_zone_t *zone, void *uap);
+
+static isc_result_t
+doneloading(dns_zt_t *zt, dns_zone_t *zone, isc_task_t *task);
+
+isc_result_t
+dns_zt_create(isc_mem_t *mctx, dns_rdataclass_t rdclass, dns_zt_t **ztp) {
+	dns_zt_t *zt;
+	isc_result_t result;
+
+	REQUIRE(ztp != NULL && *ztp == NULL);
+
+	zt = isc_mem_get(mctx, sizeof(*zt));
+	if (zt == NULL)
+		return (ISC_R_NOMEMORY);
+
+	zt->table = NULL;
+	result = dns_rbt_create(mctx, auto_detach, zt, &zt->table);
+	if (result != ISC_R_SUCCESS)
+		goto cleanup_zt;
+
+	result = isc_rwlock_init(&zt->rwlock, 0, 0);
+	if (result != ISC_R_SUCCESS)
+		goto cleanup_rbt;
+
+	zt->mctx = NULL;
+	isc_mem_attach(mctx, &zt->mctx);
+	zt->references = 1;
+	zt->flush = false;
+	zt->rdclass = rdclass;
+	zt->magic = ZTMAGIC;
+	zt->loaddone = NULL;
+	zt->loaddone_arg = NULL;
+	zt->loads_pending = 0;
+	*ztp = zt;
+
+	return (ISC_R_SUCCESS);
+
+   cleanup_rbt:
+	dns_rbt_destroy(&zt->table);
+
+   cleanup_zt:
+	isc_mem_put(mctx, zt, sizeof(*zt));
+
+	return (result);
+}
+
+isc_result_t
+dns_zt_mount(dns_zt_t *zt, dns_zone_t *zone) {
+	isc_result_t result;
+	dns_zone_t *dummy = NULL;
+	dns_name_t *name;
+
+	REQUIRE(VALID_ZT(zt));
+
+	name = dns_zone_getorigin(zone);
+
+	RWLOCK(&zt->rwlock, isc_rwlocktype_write);
+
+	result = dns_rbt_addname(zt->table, name, zone);
+	if (result == ISC_R_SUCCESS)
+		dns_zone_attach(zone, &dummy);
+
+	RWUNLOCK(&zt->rwlock, isc_rwlocktype_write);
+
+	return (result);
+}
+
+isc_result_t
+dns_zt_unmount(dns_zt_t *zt, dns_zone_t *zone) {
+	isc_result_t result;
+	dns_name_t *name;
+
+	REQUIRE(VALID_ZT(zt));
+
+	name = dns_zone_getorigin(zone);
+
+	RWLOCK(&zt->rwlock, isc_rwlocktype_write);
+
+	result = dns_rbt_deletename(zt->table, name, false);
+
+	RWUNLOCK(&zt->rwlock, isc_rwlocktype_write);
+
+	return (result);
+}
+
+isc_result_t
+dns_zt_find(dns_zt_t *zt, const dns_name_t *name, unsigned int options,
+	    dns_name_t *foundname, dns_zone_t **zonep)
+{
+	isc_result_t result;
+	dns_zone_t *dummy = NULL;
+	unsigned int rbtoptions = 0;
+
+	REQUIRE(VALID_ZT(zt));
+
+	if ((options & DNS_ZTFIND_NOEXACT) != 0)
+		rbtoptions |= DNS_RBTFIND_NOEXACT;
+
+	RWLOCK(&zt->rwlock, isc_rwlocktype_read);
+
+	result = dns_rbt_findname(zt->table, name, rbtoptions, foundname,
+				  (void **) (void*)&dummy);
+	if (result == ISC_R_SUCCESS || result == DNS_R_PARTIALMATCH)
+		dns_zone_attach(dummy, zonep);
+
+	RWUNLOCK(&zt->rwlock, isc_rwlocktype_read);
+
+	return (result);
+}
+
+void
+dns_zt_attach(dns_zt_t *zt, dns_zt_t **ztp) {
+
+	REQUIRE(VALID_ZT(zt));
+	REQUIRE(ztp != NULL && *ztp == NULL);
+
+	RWLOCK(&zt->rwlock, isc_rwlocktype_write);
+
+	INSIST(zt->references > 0);
+	zt->references++;
+	INSIST(zt->references != 0);
+
+	RWUNLOCK(&zt->rwlock, isc_rwlocktype_write);
+
+	*ztp = zt;
+}
+
+static isc_result_t
+flush(dns_zone_t *zone, void *uap) {
+	UNUSED(uap);
+	return (dns_zone_flush(zone));
+}
+
+static void
+zt_destroy(dns_zt_t *zt) {
+	if (zt->flush)
+		(void)dns_zt_apply(zt, false, flush, NULL);
+	dns_rbt_destroy(&zt->table);
+	isc_rwlock_destroy(&zt->rwlock);
+	zt->magic = 0;
+	isc_mem_putanddetach(&zt->mctx, zt, sizeof(*zt));
+}
+
+static void
+zt_flushanddetach(dns_zt_t **ztp, bool need_flush) {
+	bool destroy = false;
+	dns_zt_t *zt;
+
+	REQUIRE(ztp != NULL && VALID_ZT(*ztp));
+
+	zt = *ztp;
+
+	RWLOCK(&zt->rwlock, isc_rwlocktype_write);
+
+	INSIST(zt->references > 0);
+	zt->references--;
+	if (zt->references == 0)
+		destroy = true;
+	if (need_flush)
+		zt->flush = true;
+
+	RWUNLOCK(&zt->rwlock, isc_rwlocktype_write);
+
+	if (destroy)
+		zt_destroy(zt);
+
+	*ztp = NULL;
+}
+
+void
+dns_zt_flushanddetach(dns_zt_t **ztp) {
+	zt_flushanddetach(ztp, true);
+}
+
+void
+dns_zt_detach(dns_zt_t **ztp) {
+	zt_flushanddetach(ztp, false);
+}
+
+isc_result_t
+dns_zt_load(dns_zt_t *zt, bool stop) {
+	isc_result_t result;
+
+	REQUIRE(VALID_ZT(zt));
+
+	RWLOCK(&zt->rwlock, isc_rwlocktype_read);
+	result = dns_zt_apply(zt, stop, load, NULL);
+	RWUNLOCK(&zt->rwlock, isc_rwlocktype_read);
+	return (result);
+}
+
+static isc_result_t
+load(dns_zone_t *zone, void *uap) {
+	isc_result_t result;
+	UNUSED(uap);
+
+	result = dns_zone_load(zone);
+	if (result == DNS_R_CONTINUE || result == DNS_R_UPTODATE)
+		result = ISC_R_SUCCESS;
+
+	return (result);
+}
+
+isc_result_t
+dns_zt_asyncload(dns_zt_t *zt, dns_zt_allloaded_t alldone, void *arg) {
+	return (dns_zt_asyncload2(zt, alldone, arg, false));
+}
+
+isc_result_t
+dns_zt_asyncload2(dns_zt_t *zt, dns_zt_allloaded_t alldone, void *arg,
+		  bool newonly)
+{
+	isc_result_t result;
+	struct zt_load_params params;
+	params.dl = doneloading;
+	params.newonly = newonly;
+	params.zt = zt;
+	int pending;
+
+	REQUIRE(VALID_ZT(zt));
+
+	RWLOCK(&zt->rwlock, isc_rwlocktype_write);
+
+	INSIST(zt->loads_pending == 0);
+	result = dns_zt_apply2(zt, false, NULL, asyncload, &params);
+
+	pending = zt->loads_pending;
+	if (pending != 0) {
+		zt->loaddone = alldone;
+		zt->loaddone_arg = arg;
+	}
+
+	RWUNLOCK(&zt->rwlock, isc_rwlocktype_write);
+
+	if (pending == 0)
+		alldone(arg);
+
+	return (result);
+}
+
+/*
+ * Initiates asynchronous loading of zone 'zone'.  'callback' is a
+ * pointer to a function which will be used to inform the caller when
+ * the zone loading is complete.
+ */
+static isc_result_t
+asyncload(dns_zone_t *zone, void *paramsv) {
+	isc_result_t result;
+	struct zt_load_params * params = (struct zt_load_params*) paramsv;
+
+	dns_zt_t *zt = params->zt;
+
+	REQUIRE(zone != NULL);
+	zt = dns_zone_getview(zone)->zonetable;
+	INSIST(VALID_ZT(zt));
+
+	INSIST(zt->references > 0);
+	zt->references++;
+	zt->loads_pending++;
+
+	result = dns_zone_asyncload2(zone, *params->dl, zt, params->newonly);
+	if (result != ISC_R_SUCCESS) {
+		zt->references--;
+		zt->loads_pending--;
+		INSIST(zt->references > 0);
+	}
+	return (ISC_R_SUCCESS);
+}
+
+isc_result_t
+dns_zt_loadnew(dns_zt_t *zt, bool stop) {
+	isc_result_t result;
+
+	REQUIRE(VALID_ZT(zt));
+
+	RWLOCK(&zt->rwlock, isc_rwlocktype_read);
+	result = dns_zt_apply(zt, stop, loadnew, NULL);
+	RWUNLOCK(&zt->rwlock, isc_rwlocktype_read);
+	return (result);
+}
+
+static isc_result_t
+loadnew(dns_zone_t *zone, void *uap) {
+	isc_result_t result;
+	UNUSED(uap);
+
+	result = dns_zone_loadnew(zone);
+	if (result == DNS_R_CONTINUE || result == DNS_R_UPTODATE ||
+	    result == DNS_R_DYNAMIC)
+		result = ISC_R_SUCCESS;
+	return (result);
+}
+
+isc_result_t
+dns_zt_freezezones(dns_zt_t *zt, bool freeze) {
+	isc_result_t result, tresult;
+
+	REQUIRE(VALID_ZT(zt));
+
+	RWLOCK(&zt->rwlock, isc_rwlocktype_read);
+	result = dns_zt_apply2(zt, false, &tresult, freezezones, &freeze);
+	RWUNLOCK(&zt->rwlock, isc_rwlocktype_read);
+	if (tresult == ISC_R_NOTFOUND)
+		tresult = ISC_R_SUCCESS;
+	return ((result == ISC_R_SUCCESS) ? tresult : result);
+}
+
+static isc_result_t
+freezezones(dns_zone_t *zone, void *uap) {
+	bool freeze = *(bool *)uap;
+	bool frozen;
+	isc_result_t result = ISC_R_SUCCESS;
+	char classstr[DNS_RDATACLASS_FORMATSIZE];
+	char zonename[DNS_NAME_FORMATSIZE];
+	dns_zone_t *raw = NULL;
+	dns_view_t *view;
+	const char *vname;
+	const char *sep;
+	int level;
+
+	dns_zone_getraw(zone, &raw);
+	if (raw != NULL)
+		zone = raw;
+	if (dns_zone_gettype(zone) != dns_zone_master) {
+		if (raw != NULL)
+			dns_zone_detach(&raw);
+		return (ISC_R_SUCCESS);
+	}
+	if (!dns_zone_isdynamic(zone, true)) {
+		if (raw != NULL)
+			dns_zone_detach(&raw);
+		return (ISC_R_SUCCESS);
+	}
+
+	frozen = dns_zone_getupdatedisabled(zone);
+	if (freeze) {
+		if (frozen)
+			result = DNS_R_FROZEN;
+		if (result == ISC_R_SUCCESS)
+			result = dns_zone_flush(zone);
+		if (result == ISC_R_SUCCESS)
+			dns_zone_setupdatedisabled(zone, freeze);
+	} else {
+		if (frozen) {
+			result = dns_zone_loadandthaw(zone);
+			if (result == DNS_R_CONTINUE ||
+			    result == DNS_R_UPTODATE)
+				result = ISC_R_SUCCESS;
+		}
+	}
+	view = dns_zone_getview(zone);
+	if (strcmp(view->name, "_bind") == 0 ||
+	    strcmp(view->name, "_default") == 0)
+	{
+		vname = "";
+		sep = "";
+	} else {
+		vname = view->name;
+		sep = " ";
+	}
+	dns_rdataclass_format(dns_zone_getclass(zone), classstr,
+			      sizeof(classstr));
+	dns_name_format(dns_zone_getorigin(zone), zonename, sizeof(zonename));
+	level = (result != ISC_R_SUCCESS) ? ISC_LOG_ERROR : ISC_LOG_DEBUG(1);
+	isc_log_write(dns_lctx, DNS_LOGCATEGORY_GENERAL, DNS_LOGMODULE_ZONE,
+		      level, "%s zone '%s/%s'%s%s: %s",
+		      freeze ? "freezing" : "thawing",
+		      zonename, classstr, sep, vname,
+		      isc_result_totext(result));
+	if (raw != NULL)
+		dns_zone_detach(&raw);
+	return (result);
+}
+
+void
+dns_zt_setviewcommit(dns_zt_t *zt) {
+	dns_rbtnode_t *node;
+	dns_rbtnodechain_t chain;
+	isc_result_t result;
+
+	REQUIRE(VALID_ZT(zt));
+
+	dns_rbtnodechain_init(&chain, zt->mctx);
+
+	result = dns_rbtnodechain_first(&chain, zt->table, NULL, NULL);
+	while (result == DNS_R_NEWORIGIN || result == ISC_R_SUCCESS) {
+		result = dns_rbtnodechain_current(&chain, NULL, NULL,
+						  &node);
+		if (result == ISC_R_SUCCESS && node->data != NULL) {
+			dns_zone_setviewcommit(node->data);
+		}
+
+		result = dns_rbtnodechain_next(&chain, NULL, NULL);
+	}
+
+	dns_rbtnodechain_invalidate(&chain);
+}
+
+void
+dns_zt_setviewrevert(dns_zt_t *zt) {
+	dns_rbtnode_t *node;
+	dns_rbtnodechain_t chain;
+	isc_result_t result;
+
+	REQUIRE(VALID_ZT(zt));
+
+	dns_rbtnodechain_init(&chain, zt->mctx);
+
+	result = dns_rbtnodechain_first(&chain, zt->table, NULL, NULL);
+	while (result == DNS_R_NEWORIGIN || result == ISC_R_SUCCESS) {
+		result = dns_rbtnodechain_current(&chain, NULL, NULL,
+						  &node);
+		if (result == ISC_R_SUCCESS && node->data != NULL) {
+			dns_zone_setviewrevert(node->data);
+		}
+
+		result = dns_rbtnodechain_next(&chain, NULL, NULL);
+	}
+
+	dns_rbtnodechain_invalidate(&chain);
+}
+
+isc_result_t
+dns_zt_apply(dns_zt_t *zt, bool stop,
+	     isc_result_t (*action)(dns_zone_t *, void *), void *uap)
+{
+	return (dns_zt_apply2(zt, stop, NULL, action, uap));
+}
+
+isc_result_t
+dns_zt_apply2(dns_zt_t *zt, bool stop, isc_result_t *sub,
+	      isc_result_t (*action)(dns_zone_t *, void *), void *uap)
+{
+	dns_rbtnode_t *node;
+	dns_rbtnodechain_t chain;
+	isc_result_t result, tresult = ISC_R_SUCCESS;
+	dns_zone_t *zone;
+
+	REQUIRE(VALID_ZT(zt));
+	REQUIRE(action != NULL);
+
+	dns_rbtnodechain_init(&chain, zt->mctx);
+	result = dns_rbtnodechain_first(&chain, zt->table, NULL, NULL);
+	if (result == ISC_R_NOTFOUND) {
+		/*
+		 * The tree is empty.
+		 */
+		tresult = result;
+		result = ISC_R_NOMORE;
+	}
+	while (result == DNS_R_NEWORIGIN || result == ISC_R_SUCCESS) {
+		result = dns_rbtnodechain_current(&chain, NULL, NULL,
+						  &node);
+		if (result == ISC_R_SUCCESS) {
+			zone = node->data;
+			if (zone != NULL)
+				result = (action)(zone, uap);
+			if (result != ISC_R_SUCCESS && stop) {
+				tresult = result;
+				goto cleanup;	/* don't break */
+			} else if (result != ISC_R_SUCCESS &&
+				   tresult == ISC_R_SUCCESS)
+				tresult = result;
+		}
+		result = dns_rbtnodechain_next(&chain, NULL, NULL);
+	}
+	if (result == ISC_R_NOMORE)
+		result = ISC_R_SUCCESS;
+
+ cleanup:
+	dns_rbtnodechain_invalidate(&chain);
+	if (sub != NULL)
+		*sub = tresult;
+
+	return (result);
+}
+
+/*
+ * Decrement the loads_pending counter; when counter reaches
+ * zero, call the loaddone callback that was initially set by
+ * dns_zt_asyncload().
+ */
+static isc_result_t
+doneloading(dns_zt_t *zt, dns_zone_t *zone, isc_task_t *task) {
+	bool destroy = false;
+	dns_zt_allloaded_t alldone = NULL;
+	void *arg = NULL;
+
+	UNUSED(zone);
+	UNUSED(task);
+
+	REQUIRE(VALID_ZT(zt));
+
+	RWLOCK(&zt->rwlock, isc_rwlocktype_write);
+	INSIST(zt->loads_pending != 0);
+	INSIST(zt->references != 0);
+	zt->references--;
+	if (zt->references == 0)
+		destroy = true;
+	zt->loads_pending--;
+	if (zt->loads_pending == 0) {
+		alldone = zt->loaddone;
+		arg = zt->loaddone_arg;
+		zt->loaddone = NULL;
+		zt->loaddone_arg = NULL;
+	}
+	RWUNLOCK(&zt->rwlock, isc_rwlocktype_write);
+
+	if (alldone != NULL)
+		alldone(arg);
+
+	if (destroy)
+		zt_destroy(zt);
+
+	return (ISC_R_SUCCESS);
+}
+
+/***
+ *** Private
+ ***/
+
+static void
+auto_detach(void *data, void *arg) {
+	dns_zone_t *zone = data;
+
+	UNUSED(arg);
+	dns_zone_detach(&zone);
+}