vendor/unbound/1.6.7

2 files changed, 16 insertions, 7 deletions

diff --git a/services/cache/dns.c b/services/cache/dns.c
index da43c504dfa3..f9dc5922f682 100644
--- a/services/cache/dns.c
+++ b/services/cache/dns.c
@@ -111,7 +111,7 @@ store_rrsets(struct module_env* env, struct reply_info* rep, time_t now,
 void 
 dns_cache_store_msg(struct module_env* env, struct query_info* qinfo,
 	hashvalue_type hash, struct reply_info* rep, time_t leeway, int pside,
-	struct reply_info* qrep, struct regional* region)
+	struct reply_info* qrep, uint32_t flags, struct regional* region)
 {
 	struct msgreply_entry* e;
 	time_t ttl = rep->ttl;
@@ -127,7 +127,7 @@ dns_cache_store_msg(struct module_env* env, struct query_info* qinfo,
 	 * unnecessary, because the cache gets locked per rrset. */
 	reply_info_set_ttls(rep, *env->now);
 	store_rrsets(env, rep, *env->now, leeway, pside, qrep, region);
-	if(ttl == 0) {
+	if(ttl == 0 && !(flags & DNSCACHE_STORE_ZEROTTL)) {
 		/* we do not store the message, but we did store the RRs,
 		 * which could be useful for delegation information */
 		verbose(VERB_ALGO, "TTL 0: dropped msg from cache");
@@ -845,7 +845,7 @@ dns_cache_lookup(struct module_env* env,
 int 
 dns_cache_store(struct module_env* env, struct query_info* msgqinf,
         struct reply_info* msgrep, int is_referral, time_t leeway, int pside,
-	struct regional* region, uint16_t flags)
+	struct regional* region, uint32_t flags)
 {
 	struct reply_info* rep = NULL;
 	/* alloc, malloc properly (not in region, like msg is) */
@@ -890,9 +890,9 @@ dns_cache_store(struct module_env* env, struct query_info* msgqinf,
 		 * Not AA from cache. Not CD in cache (depends on client bit). */
 		rep->flags |= (BIT_RA | BIT_QR);
 		rep->flags &= ~(BIT_AA | BIT_CD);
-		h = query_info_hash(&qinf, flags);
+		h = query_info_hash(&qinf, (uint16_t)flags);
 		dns_cache_store_msg(env, &qinf, h, rep, leeway, pside, msgrep,
-			region);
+			flags, region);
 		/* qname is used inside query_info_entrysetup, and set to 
 		 * NULL. If it has not been used, free it. free(0) is safe. */
 		free(qinf.qname);
diff --git a/services/cache/dns.h b/services/cache/dns.h
index 096ddf28db63..9e10f437f1b4 100644
--- a/services/cache/dns.h
+++ b/services/cache/dns.h
@@ -49,6 +49,12 @@ struct reply_info;
 struct regional;
 struct delegpt;
 
+/** Flags to control behavior of dns_cache_store() and dns_cache_store_msg().
+ *  Must be an unsigned 32-bit value larger than 0xffff */
+
+/** Allow caching a DNS message with a zero TTL. */
+#define DNSCACHE_STORE_ZEROTTL 0x100000
+
 /**
  * Region allocated message reply
  */
@@ -80,11 +86,13 @@ struct dns_msg {
  * @param region: region to allocate better entries from cache into.
  *   (used when is_referral is false).
  * @param flags: flags with BIT_CD for AAAA queries in dns64 translation.
+ *   The higher 16 bits are used internally to customize the cache policy.
+ *   (See DNSCACHE_STORE_xxx flags).
  * @return 0 on alloc error (out of memory).
  */
 int dns_cache_store(struct module_env* env, struct query_info* qinf,
         struct reply_info* rep, int is_referral, time_t leeway, int pside,
-	struct regional* region, uint16_t flags); 
+	struct regional* region, uint32_t flags);
 
 /**
  * Store message in the cache. Stores in message cache and rrset cache.
@@ -103,11 +111,12 @@ int dns_cache_store(struct module_env* env, struct query_info* qinf,
  * 	from the parentside of the zonecut.  This means that the type NS
  * 	can be updated to full TTL even in prefetch situations.
  * @param qrep: message that can be altered with better rrs from cache.
+ * @param flags: customization flags for the cache policy.
  * @param region: to allocate into for qmsg.
  */
 void dns_cache_store_msg(struct module_env* env, struct query_info* qinfo,
 	hashvalue_type hash, struct reply_info* rep, time_t leeway, int pside,
-	struct reply_info* qrep, struct regional* region);
+	struct reply_info* qrep, uint32_t flags, struct regional* region);
 
 /**
  * Find a delegation from the cache.