Add -expired flag to rndc dumpdb command

This flag is the same as -cache, but will use a different style format
that will also print expired entries (awaiting cleanup) from the cache.

bin/named/server.c

@@ -243,6 +243,7 @@ struct dumpcontext {
 	bool dumpzones;
 	bool dumpadb;
 	bool dumpbad;
+	bool dumpexpired;
 	bool dumpfail;
 	FILE *fp;
 	ISC_LIST(struct viewlistentry) viewlist;
@@ -11052,7 +11053,11 @@ resume:
 			dns_cache_getname(dctx->view->view->cache));
 	} else if (dctx->zone == NULL && dctx->cache == NULL && dctx->dumpcache)
 	{
-		style = &dns_master_style_cache;
+		if (dctx->dumpexpired) {
+			style = &dns_master_style_cache_with_expired;
+		} else {
+			style = &dns_master_style_cache;
+		}
 		/* start cache dump */
 		if (dctx->view->view->cachedb != NULL) {
 			dns_db_attach(dctx->view->view->cachedb, &dctx->cache);
@@ -11186,6 +11191,7 @@ named_server_dumpdb(named_server_t *server, isc_lex_t *lex,
 	dctx->dumpcache = true;
 	dctx->dumpadb = true;
 	dctx->dumpbad = true;
+	dctx->dumpexpired = false;
 	dctx->dumpfail = true;
 	dctx->dumpzones = false;
 	dctx->fp = NULL;
@@ -11216,6 +11222,10 @@ named_server_dumpdb(named_server_t *server, isc_lex_t *lex,
 	} else if (ptr != NULL && strcmp(ptr, "-cache") == 0) {
 		/* this is the default */
 		ptr = next_token(lex, NULL);
+	} else if (ptr != NULL && strcmp(ptr, "-expired") == 0) {
+		/* this is the same as -cache but includes expired data */
+		dctx->dumpexpired = true;
+		ptr = next_token(lex, NULL);
 	} else if (ptr != NULL && strcmp(ptr, "-zones") == 0) {
 		/* only dump zones, suppress caches */
 		dctx->dumpadb = false;

bin/rndc/rndc.c

@@ -124,7 +124,7 @@ command is one of the following:\n\
 		Close, truncate and re-open the DNSTAP output file.\n\
   dnstap -roll count\n\
 		Close, rename and re-open the DNSTAP output file(s).\n\
-  dumpdb [-all|-cache|-zones|-adb|-bad|-fail] [view ...]\n\
+  dumpdb [-all|-cache|-zones|-adb|-bad|-expired|-fail] [view ...]\n\
 		Dump cache(s) to the dump file (named_dump.db).\n\
   flush         Flushes all of the server's caches.\n\
   flush [view]	Flushes the server's cache for a view.\n\

bin/rndc/rndc.rst

@@ -186,7 +186,7 @@ Currently supported commands are:
    output file is moved to ".1", and so on. If ``number`` is specified, then
    the number of backup log files is limited to that number.
 
-``dumpdb`` [**-all** | **-cache** | **-zones** | **-adb** | **-bad** | **-fail**] [*view ...*]
+``dumpdb`` [**-all** | **-cache** | **-zones** | **-adb** | **-bad** | **-expired** | **-fail**] [*view ...*]
    This command dumps the server's caches (default) and/or zones to the dump file for
    the specified views. If no view is specified, all views are dumped.
    (See the ``dump-file`` option in the BIND 9 Administrator Reference

doc/man/rndc.8in

@@ -186,7 +186,7 @@ output file has ".0" appended to its name; the previous most recent
 output file is moved to ".1", and so on. If \fBnumber\fP is specified, then
 the number of backup log files is limited to that number.
 .TP
-\fBdumpdb\fP [\fB\-all\fP | \fB\-cache\fP | \fB\-zones\fP | \fB\-adb\fP | \fB\-bad\fP | \fB\-fail\fP] [\fIview ...\fP]
+\fBdumpdb\fP [\fB\-all\fP | \fB\-cache\fP | \fB\-zones\fP | \fB\-adb\fP | \fB\-bad\fP | \fB\-expired\fP | \fB\-fail\fP] [\fIview ...\fP]
 This command dumps the server\(aqs caches (default) and/or zones to the dump file for
 the specified views. If no view is specified, all views are dumped.
 (See the \fBdump\-file\fP option in the BIND 9 Administrator Reference

lib/dns/include/dns/masterdump.h

@@ -110,6 +110,9 @@ typedef struct dns_master_style dns_master_style_t;
 /*% Print ECS cache entries as comments (reserved for future use). */
 #define DNS_STYLEFLAG_ECSCACHE 0x100000000ULL
 
+/*% Print expired cache entries. */
+#define DNS_STYLEFLAG_EXPIRED 0x200000000ULL
+
 ISC_LANG_BEGINDECLS
 
 /***
@@ -145,6 +148,13 @@ LIBDNS_EXTERNAL_DATA extern const dns_master_style_t
  */
 LIBDNS_EXTERNAL_DATA extern const dns_master_style_t dns_master_style_cache;
 
+/*%
+ * A master style format designed for cache files.  The same as above but
+ * this also prints expired entries.
+ */
+LIBDNS_EXTERNAL_DATA extern const dns_master_style_t
+	dns_master_style_cache_with_expired;
+
 /*%
  * A master style that prints name, ttl, class, type, and value on
  * every line.  Similar to explicitttl above, but more verbose.

lib/dns/include/dns/rdataset.h

@@ -188,6 +188,7 @@ struct dns_rdataset {
 #define DNS_RDATASETATTR_PREFETCH     0x00400000
 #define DNS_RDATASETATTR_CYCLIC	      0x00800000 /*%< Cyclic ordering. */
 #define DNS_RDATASETATTR_STALE	      0x01000000
+#define DNS_RDATASETATTR_ANCIENT      0x02000000
 
 /*%
  * _OMITDNSSEC:

lib/dns/masterdump.c

@@ -85,6 +85,8 @@ struct dns_master_style {
 
 /*% Does the rdataset 'r' contain a stale answer? */
 #define STALE(r) (((r)->attributes & DNS_RDATASETATTR_STALE) != 0)
+/*% Does the rdataset 'r' contain an expired answer? */
+#define ANCIENT(r) (((r)->attributes & DNS_RDATASETATTR_ANCIENT) != 0)
 
 /*%
  * Context structure for a masterfile dump in progress.
@@ -171,6 +173,21 @@ LIBDNS_EXTERNAL_DATA const dns_master_style_t dns_master_style_cache = {
 	UINT_MAX
 };
 
+LIBDNS_EXTERNAL_DATA const dns_master_style_t
+	dns_master_style_cache_with_expired = {
+		DNS_STYLEFLAG_OMIT_OWNER | DNS_STYLEFLAG_OMIT_CLASS |
+			DNS_STYLEFLAG_MULTILINE | DNS_STYLEFLAG_RRCOMMENT |
+			DNS_STYLEFLAG_TRUST | DNS_STYLEFLAG_NCACHE |
+			DNS_STYLEFLAG_EXPIRED,
+		24,
+		32,
+		32,
+		40,
+		80,
+		8,
+		UINT_MAX
+	};
+
 LIBDNS_EXTERNAL_DATA const dns_master_style_t dns_master_style_simple = {
 	0, 24, 32, 32, 40, 80, 8, UINT_MAX
 };
@@ -1065,6 +1082,14 @@ again:
 
 	for (i = 0; i < n; i++) {
 		dns_rdataset_t *rds = sorted[i];
+
+		if (ANCIENT(rds) &&
+		    (ctx->style.flags & DNS_STYLEFLAG_EXPIRED) == 0) {
+			/* Omit expired entries */
+			dns_rdataset_disassociate(rds);
+			continue;
+		}
+
 		if ((ctx->style.flags & DNS_STYLEFLAG_TRUST) != 0) {
 			if ((ctx->style.flags & DNS_STYLEFLAG_INDENT) != 0 ||
 			    (ctx->style.flags & DNS_STYLEFLAG_YAML) != 0)
@@ -1084,10 +1109,12 @@ again:
 			isc_result_t result;
 			if (STALE(rds)) {
 				fprintf(f,
-					"; stale (will be retained for "
+					"; stale (will be retained for %u more "
-					"%u more seconds)\n",
+					"seconds)\n",
 					(rds->stale_ttl -
 					 ctx->serve_stale_ttl));
+			} else if (ANCIENT(rds)) {
+				fprintf(f, "; expired (awaiting cleanup)\n");
 			}
 			result = dump_rdataset(mctx, name, rds, ctx, buffer, f);
 			if (result != ISC_R_SUCCESS) {