From: Mark Andrews <marka@isc.org>
Date: Wed, 16 Nov 2022 00:40:33 +0000 (+1100)
Subject: Add dns_db_allrdatasets options
X-Git-Tag: v9.19.8~7^2~2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=85048ddeeeba8414ababfe73ba2651183b056180;p=thirdparty%2Fbind9.git

Add dns_db_allrdatasets options

'DNS_DB_STALEOK' returns stale rdatasets as well as current rdatasets.

'DNS_DB_EXPIREDOK' returns expired rdatasets as well as current
rdatasets. This option is currently only set when DNS_DB_STALEOK is
also set.
---

diff --git a/lib/dns/cache.c b/lib/dns/cache.c
index 966485b50e7..7aedbb6fb56 100644
--- a/lib/dns/cache.c
+++ b/lib/dns/cache.c
@@ -392,8 +392,8 @@ clearnode(dns_db_t *db, dns_dbnode_t *node) {
 	isc_result_t result;
 	dns_rdatasetiter_t *iter = NULL;
 
-	result = dns_db_allrdatasets(db, node, NULL, 0, (isc_stdtime_t)0,
-				     &iter);
+	result = dns_db_allrdatasets(db, node, NULL, DNS_DB_STALEOK,
+				     (isc_stdtime_t)0, &iter);
 	if (result != ISC_R_SUCCESS) {
 		return (result);
 	}
diff --git a/lib/dns/include/dns/db.h b/lib/dns/include/dns/db.h
index 9673f967f07..b15279c9eef 100644
--- a/lib/dns/include/dns/db.h
+++ b/lib/dns/include/dns/db.h
@@ -302,6 +302,9 @@ struct dns_dbonupdatelistener {
 #define DNS_DB_NONSEC3	     0x4
 /*@}*/
 
+#define DNS_DB_STALEOK	 0x01
+#define DNS_DB_EXPIREDOK 0x02
+
 /*****
 ***** Methods
 *****/
@@ -1168,6 +1171,9 @@ dns_db_allrdatasets(dns_db_t *db, dns_dbnode_t *node, dns_dbversion_t *version,
  *
  * \li	'options' controls which rdatasets are selected when interating over
  *	the node.
+ *	'DNS_DB_STALEOK' return stale rdatasets as well as current rdatasets.
+ *	'DNS_DB_EXPIREDOK' return expired rdatasets as well as current
+ *	rdatasets.
  *
  * \li	The 'now' field is ignored if 'db' is a zone database.  If 'db' is a
  *	cache database, an rdataset will not be found unless it expires after
diff --git a/lib/dns/masterdump.c b/lib/dns/masterdump.c
index 2fdda1ce8df..0c6aeb18d6a 100644
--- a/lib/dns/masterdump.c
+++ b/lib/dns/masterdump.c
@@ -1669,6 +1669,11 @@ dumptostream(dns_dumpctx_t *dctx) {
 	char *bufmem;
 	dns_name_t *name;
 	dns_fixedname_t fixname;
+	unsigned int options = DNS_DB_STALEOK;
+
+	if ((dctx->tctx.style.flags & DNS_STYLEFLAG_EXPIRED) != 0) {
+		options |= DNS_DB_EXPIREDOK;
+	}
 
 	bufmem = isc_mem_get(dctx->mctx, initial_buffer_length);
 
@@ -1707,8 +1712,8 @@ dumptostream(dns_dumpctx_t *dctx) {
 		result = dns_dbiterator_pause(dctx->dbiter);
 		RUNTIME_CHECK(result == ISC_R_SUCCESS);
 
-		result = dns_db_allrdatasets(dctx->db, node, dctx->version, 0,
-					     dctx->now, &rdsiter);
+		result = dns_db_allrdatasets(dctx->db, node, dctx->version,
+					     options, dctx->now, &rdsiter);
 		if (result != ISC_R_SUCCESS) {
 			dns_db_detachnode(dctx->db, &node);
 			goto cleanup;
@@ -1916,6 +1921,11 @@ dns_master_dumpnodetostream(isc_mem_t *mctx, dns_db_t *db,
 	isc_stdtime_t now;
 	dns_totext_ctx_t ctx;
 	dns_rdatasetiter_t *rdsiter = NULL;
+	unsigned int options = DNS_DB_STALEOK;
+
+	if ((style->flags & DNS_STYLEFLAG_EXPIRED) != 0) {
+		options |= DNS_DB_EXPIREDOK;
+	}
 
 	result = totext_ctx_init(style, NULL, &ctx);
 	if (result != ISC_R_SUCCESS) {
@@ -1929,7 +1939,7 @@ dns_master_dumpnodetostream(isc_mem_t *mctx, dns_db_t *db,
 
 	isc_buffer_init(&buffer, bufmem, initial_buffer_length);
 
-	result = dns_db_allrdatasets(db, node, version, 0, now, &rdsiter);
+	result = dns_db_allrdatasets(db, node, version, options, now, &rdsiter);
 	if (result != ISC_R_SUCCESS) {
 		goto failure;
 	}
diff --git a/lib/dns/rbtdb.c b/lib/dns/rbtdb.c
index aae127b6fbc..388e7540376 100644
--- a/lib/dns/rbtdb.c
+++ b/lib/dns/rbtdb.c
@@ -444,6 +444,12 @@ typedef ISC_LIST(dns_rbtnode_t) rbtnodelist_t;
 
 #define DEFAULT_NODE_LOCK_COUNT 7 /*%< Should be prime. */
 
+#define EXPIREDOK(rbtiterator) \
+	(((rbtiterator)->common.options & DNS_DB_EXPIREDOK) != 0)
+
+#define STALEOK(rbtiterator) \
+	(((rbtiterator)->common.options & DNS_DB_STALEOK) != 0)
+
 /*%
  * Number of buckets for cache DB entries (locks, LRU lists, TTL heaps).
  * There is a tradeoff issue about configuring this value: if this is too
@@ -8858,7 +8864,17 @@ rdatasetiter_first(dns_rdatasetiter_t *iterator) {
 	for (header = rbtnode->data; header != NULL; header = top_next) {
 		top_next = header->next;
 		do {
-			if (header->serial <= serial && !IGNORE(header)) {
+			dns_ttl_t stale_ttl = header->rdh_ttl;
+			if (STALEOK(rbtiterator)) {
+				stale_ttl += STALE_TTL(header, rbtdb);
+			}
+			if (EXPIREDOK(rbtiterator)) {
+				if (!NONEXISTENT(header)) {
+					break;
+				}
+				header = header->down;
+			} else if (header->serial <= serial && !IGNORE(header))
+			{
 				/*
 				 * Is this a "this rdataset doesn't exist"
 				 * record?  Or is it too old in the cache?
@@ -8869,8 +8885,7 @@ rdatasetiter_first(dns_rdatasetiter_t *iterator) {
 				 *  queries for 0 TTL rdatasets to work.
 				 */
 				if (NONEXISTENT(header) ||
-				    (now != 0 && now > header->rdh_ttl))
-				{
+				    (now != 0 && now > stale_ttl)) {
 					header = NULL;
 				}
 				break;
@@ -8906,6 +8921,7 @@ rdatasetiter_next(dns_rdatasetiter_t *iterator) {
 	rbtdb_rdatatype_t type, negtype;
 	dns_rdatatype_t rdtype, covers;
 	isc_rwlocktype_t nlocktype = isc_rwlocktype_none;
+	bool expiredok = EXPIREDOK(rbtiterator);
 
 	header = rbtiterator->current;
 	if (header == NULL) {
@@ -8930,37 +8946,69 @@ rdatasetiter_next(dns_rdatasetiter_t *iterator) {
 	} else {
 		negtype = RBTDB_RDATATYPE_VALUE(0, rdtype);
 	}
-	for (header = header->next; header != NULL; header = top_next) {
-		top_next = header->next;
+
+	/*
+	 * Find the start of the header chain for the next type
+	 * by walking back up the list.
+	 */
+	top_next = header->next;
+	while (top_next != NULL &&
+	       (top_next->type == type || top_next->type == negtype))
+	{
+		top_next = top_next->next;
+	}
+	if (expiredok) {
 		/*
-		 * If not walking back up the down list.
+		 * Keep walking down the list if possible or
+		 * start the next type.
 		 */
-		if (header->type != type && header->type != negtype) {
-			do {
-				if (header->serial <= serial && !IGNORE(header))
-				{
-					/*
-					 * Is this a "this rdataset doesn't
-					 * exist" record?
-					 *
-					 * Note: unlike everywhere else, we
-					 * check for now > header->ttl instead
-					 * of ">=".  This allows ANY and RRSIG
-					 * queries for 0 TTL rdatasets to work.
-					 */
-					if (NONEXISTENT(header) ||
-					    (now != 0 && now > header->rdh_ttl))
-					{
-						header = NULL;
-					}
+		header = header->down != NULL ? header->down : top_next;
+	} else {
+		header = top_next;
+	}
+	for (; header != NULL; header = top_next) {
+		top_next = header->next;
+		do {
+			dns_ttl_t stale_ttl = header->rdh_ttl;
+			if (STALEOK(rbtiterator)) {
+				stale_ttl += STALE_TTL(header, rbtdb);
+			}
+			if (expiredok) {
+				if (!NONEXISTENT(header)) {
 					break;
-				} else {
-					header = header->down;
 				}
-			} while (header != NULL);
-			if (header != NULL) {
+				header = header->down;
+			} else if (header->serial <= serial && !IGNORE(header))
+			{
+				/*
+				 * Is this a "this rdataset doesn't
+				 * exist" record?
+				 *
+				 * Note: unlike everywhere else, we
+				 * check for now > header->ttl instead
+				 * of ">=".  This allows ANY and RRSIG
+				 * queries for 0 TTL rdatasets to work.
+				 */
+				if (NONEXISTENT(header) ||
+				    (now != 0 && now > stale_ttl)) {
+					header = NULL;
+				}
 				break;
+			} else {
+				header = header->down;
 			}
+		} while (header != NULL);
+		if (header != NULL) {
+			break;
+		}
+		/*
+		 * Find the start of the header chain for the next type
+		 * by walking back up the list.
+		 */
+		while (top_next != NULL &&
+		       (top_next->type == type || top_next->type == negtype))
+		{
+			top_next = top_next->next;
 		}
 	}