- Fix sticky NS (ghost domain problem) if prefetch is yes.

git-svn-id: file:///svn/unbound/trunk@2619 be551aaa-1e26-0410-a405-d3ace91eadb9

diff --git a/doc/Changelog b/doc/Changelog
index 19c8ac57e14aa7bb5adac02c2a368b5fb7fb36a6..fb3a32282219abe33373c81799311500981c0ab7 100644 (file)
--- a/doc/Changelog
+++ b/doc/Changelog
@@ -1,3 +1,6 @@
+14 February 2012: Wouter
+       - Fix sticky NS (ghost domain problem) if prefetch is yes.
+
 13 February 2012: Wouter
        - RT#2955. Fix for cygwin compilation. 
        - iana portlist updated.

diff --git a/services/cache/dns.c b/services/cache/dns.c
index 49234ab4154ef17548e025185cac22db77ae23ef..a6778f6ce6829e608f9cf1c1c97c1622bb83059d 100644 (file)
--- a/services/cache/dns.c
+++ b/services/cache/dns.c
@@ -55,12 +55,17 @@
  * @param env: module environment with caches.
  * @param rep: contains list of rrsets to store.
  * @param now: current time.
+ * @param leeway: during prefetch how much leeway to update TTLs.
+ *     This makes rrsets (other than type NS) timeout sooner so they get
+ *     updated with a new full TTL.
+ *     Type NS does not get this, because it must not be refreshed from the
+ *     child domain, but keep counting down properly.
  * @param qrep: update rrsets here if cache is better
  * @param region: for qrep allocs.
  */
 static void
 store_rrsets(struct module_env* env, struct reply_info* rep, uint32_t now,
-       struct reply_info* qrep, struct regional* region)
+       uint32_t leeway, struct reply_info* qrep, struct regional* region)
 {
         size_t i;
         /* see if rrset already exists in cache, if not insert it. */
@@ -69,7 +74,8 @@ store_rrsets(struct module_env* env, struct reply_info* rep, uint32_t now,
                 rep->ref[i].id = rep->rrsets[i]->id;
                /* update ref if it was in the cache */ 
                switch(rrset_cache_update(env->rrset_cache, &rep->ref[i],
-                        env->alloc, now)) {
+                        env->alloc, now + ((ntohs(rep->ref[i].key->rk.type)==
+                       LDNS_RR_TYPE_NS)?0:leeway))) {
                case 0: /* ref unchanged, item inserted */
                        break;
                case 2: /* ref updated, cache is superior */
@@ -112,7 +118,7 @@ dns_cache_store_msg(struct module_env* env, struct query_info* qinfo,
        /* there was a reply_info_sortref(rep) here but it seems to be
         * unnecessary, because the cache gets locked per rrset. */
        reply_info_set_ttls(rep, *env->now);
-       store_rrsets(env, rep, *env->now+leeway, qrep, region);
+       store_rrsets(env, rep, *env->now, leeway, qrep, region);
        if(ttl == 0) {
                /* we do not store the message, but we did store the RRs,
                 * which could be useful for delegation information */
@@ -752,8 +758,11 @@ dns_cache_store(struct module_env* env, struct query_info* msgqinf,
                        ref.key = rep->rrsets[i];
                        ref.id = rep->rrsets[i]->id;
                        /*ignore ret: it was in the cache, ref updated */
+                       /* no leeway for typeNS */
                        (void)rrset_cache_update(env->rrset_cache, &ref, 
-                               env->alloc, *env->now + leeway);
+                               env->alloc, *env->now + 
+                               ((ntohs(ref.key->rk.type)==LDNS_RR_TYPE_NS)?
+                               0:leeway));
                }
                free(rep);
                return 1;

diff --git a/testdata/iter_prefetch.rpl b/testdata/iter_prefetch.rpl
index f2b63a21dd67e890ed970a8d432bad50caa54685..efd63a59d643109fb06cd21b2e1934fe6c133016 100644 (file)
--- a/testdata/iter_prefetch.rpl
+++ b/testdata/iter_prefetch.rpl
@@ -217,7 +217,8 @@ www.example.com. IN A
 SECTION ANSWER
 www.example.com. 3600 IN A     10.20.30.40
 SECTION AUTHORITY
-example.com.   3600 IN NS      ns.example.com.
+; NS rrset TTL not updated to avoid sticky-NS (ghost domain) problem.
+example.com.   360 IN NS       ns.example.com.
 SECTION ADDITIONAL
 ns.example.com.        3600    IN      A       1.2.3.4
 ENTRY_END

diff --git a/testdata/iter_prefetch_change2.rpl b/testdata/iter_prefetch_change2.rpl
new file mode 100644 (file)
index 0000000..777454c
--- /dev/null
+++ b/testdata/iter_prefetch_change2.rpl
@@ -0,0 +1,313 @@
+; config options
+server:
+       target-fetch-policy: "0 0 0 0 0"
+       prefetch: "yes"
+
+stub-zone:
+       name: "."
+       stub-addr: 193.0.14.129         # K.ROOT-SERVERS.NET.
+CONFIG_END
+
+SCENARIO_BEGIN Test resolver prefetch and a moved domain 2.
+; for slightly different query pattern.
+
+; K.ROOT-SERVERS.NET.
+RANGE_BEGIN 0 500
+       ADDRESS 193.0.14.129 
+ENTRY_BEGIN
+MATCH opcode qtype qname
+ADJUST copy_id
+REPLY QR NOERROR
+SECTION QUESTION
+. IN NS
+SECTION ANSWER
+. IN NS        K.ROOT-SERVERS.NET.
+SECTION ADDITIONAL
+K.ROOT-SERVERS.NET.    IN      A       193.0.14.129
+ENTRY_END
+
+ENTRY_BEGIN
+MATCH opcode subdomain
+ADJUST copy_id copy_query
+REPLY QR NOERROR
+SECTION QUESTION
+com. IN A
+SECTION AUTHORITY
+com.   IN NS   a.gtld-servers.net.
+SECTION ADDITIONAL
+a.gtld-servers.net.    IN      A       192.5.6.30
+ENTRY_END
+RANGE_END
+
+; a.gtld-servers.net. (before sale of domain)
+RANGE_BEGIN 0 30
+       ADDRESS 192.5.6.30
+ENTRY_BEGIN
+MATCH opcode qtype qname
+ADJUST copy_id
+REPLY QR NOERROR
+SECTION QUESTION
+com. IN NS
+SECTION ANSWER
+com.   IN NS   a.gtld-servers.net.
+SECTION ADDITIONAL
+a.gtld-servers.net.    IN      A       192.5.6.30
+ENTRY_END
+
+ENTRY_BEGIN
+MATCH opcode subdomain
+ADJUST copy_id copy_query
+REPLY QR NOERROR
+SECTION QUESTION
+example.com. IN A
+SECTION AUTHORITY
+example.com.   86400 IN NS     old-ns.example.com.
+SECTION ADDITIONAL
+old-ns.example.com.            86400 IN        A       192.168.0.1
+ENTRY_END
+RANGE_END
+
+; a.gtld-servers.net. (after sale of domain)
+RANGE_BEGIN 40 500
+       ADDRESS 192.5.6.30
+ENTRY_BEGIN
+MATCH opcode qtype qname
+ADJUST copy_id
+REPLY QR NOERROR
+SECTION QUESTION
+com. IN NS
+SECTION ANSWER
+com.   IN NS   a.gtld-servers.net.
+SECTION ADDITIONAL
+a.gtld-servers.net.    IN      A       192.5.6.30
+ENTRY_END
+
+ENTRY_BEGIN
+MATCH opcode subdomain
+ADJUST copy_id copy_query
+REPLY QR NOERROR
+SECTION QUESTION
+example.com. IN A
+SECTION AUTHORITY
+example.com.   86400 IN NS     new-ns.example.com.
+SECTION ADDITIONAL
+new-ns.example.com.            86400 IN        A       172.16.0.1
+ENTRY_END
+RANGE_END
+
+; ns.example.com. first owner
+RANGE_BEGIN 0 500
+       ADDRESS 192.168.0.1
+ENTRY_BEGIN
+MATCH opcode qtype qname
+ADJUST copy_id
+REPLY QR AA NOERROR
+SECTION QUESTION
+example.com. IN NS
+SECTION ANSWER
+example.com.   300 IN NS       old-ns.example.com.
+SECTION ADDITIONAL
+old-ns.example.com.            300 IN  A       192.168.0.1
+ENTRY_END
+
+ENTRY_BEGIN
+MATCH opcode qtype qname
+ADJUST copy_id
+REPLY QR AA NOERROR
+SECTION QUESTION
+www.example.com. IN A
+SECTION ANSWER
+www.example.com. 300 IN A      10.1.1.1
+SECTION AUTHORITY
+example.com.   300 IN NS       old-ns.example.com.
+SECTION ADDITIONAL
+old-ns.example.com.            300 IN  A       192.168.0.1
+ENTRY_END
+RANGE_END
+
+; ns.example.com. new owner
+RANGE_BEGIN 0 500
+       ADDRESS 172.16.0.1
+ENTRY_BEGIN
+MATCH opcode qtype qname
+ADJUST copy_id
+REPLY QR AA NOERROR
+SECTION QUESTION
+example.com. IN NS
+SECTION ANSWER
+example.com.   86400 IN NS     new-ns.example.com.
+SECTION ADDITIONAL
+new-ns.example.com.            86400 IN        A       172.16.0.1
+ENTRY_END
+
+ENTRY_BEGIN
+MATCH opcode qtype qname
+ADJUST copy_id
+REPLY QR AA NOERROR
+SECTION QUESTION
+old-ns.example.com. IN A
+SECTION ANSWER
+old-ns.example.com. 86400 IN A 172.16.0.1
+SECTION AUTHORITY
+example.com.   86400 IN NS     new-ns.example.com.
+SECTION ADDITIONAL
+new-ns.example.com.            86400 IN        A       172.16.0.1
+ENTRY_END
+
+ENTRY_BEGIN
+MATCH opcode qtype qname
+ADJUST copy_id
+REPLY QR AA NOERROR
+SECTION QUESTION
+www.example.com. IN A
+SECTION ANSWER
+www.example.com. 86400 IN A    10.2.2.2
+SECTION AUTHORITY
+example.com.   86400 IN NS     new-ns.example.com.
+SECTION ADDITIONAL
+new-ns.example.com.            86400 IN        A       172.16.0.1
+ENTRY_END
+RANGE_END
+
+STEP 1 QUERY
+ENTRY_BEGIN
+REPLY RD
+SECTION QUESTION
+www.example.com. IN A
+ENTRY_END
+; recursion happens here.
+STEP 10 CHECK_ANSWER
+ENTRY_BEGIN
+MATCH all ttl
+REPLY QR RD RA NOERROR
+SECTION QUESTION
+www.example.com. IN A
+SECTION ANSWER
+www.example.com.       300 IN A        10.1.1.1
+SECTION AUTHORITY
+example.com.           300 IN NS       old-ns.example.com.
+SECTION ADDITIONAL
+old-ns.example.com.    300 IN A        192.168.0.1
+ENTRY_END
+
+; after 40 secs still the cached answer
+STEP 20 TIME_PASSES ELAPSE 40
+
+STEP 30 QUERY
+ENTRY_BEGIN
+REPLY RD
+SECTION QUESTION
+www.example.com. IN A
+ENTRY_END
+; recursion happens here.
+STEP 40 CHECK_ANSWER
+ENTRY_BEGIN
+MATCH all ttl
+REPLY QR RD RA NOERROR
+SECTION QUESTION
+www.example.com. IN A
+SECTION ANSWER
+www.example.com.       260 IN A        10.1.1.1
+SECTION AUTHORITY
+example.com.           260 IN NS       old-ns.example.com.
+SECTION ADDITIONAL
+old-ns.example.com.    260 IN A        192.168.0.1
+ENTRY_END
+
+; after 230 we are 30 seconds before expiry, prefetch happens.
+STEP 50 TIME_PASSES ELAPSE 230
+
+STEP 60 QUERY
+ENTRY_BEGIN
+REPLY RD
+SECTION QUESTION
+www.example.com. IN A
+ENTRY_END
+; recursion happens here.
+STEP 70 CHECK_ANSWER
+ENTRY_BEGIN
+MATCH all ttl
+REPLY QR RD RA NOERROR
+SECTION QUESTION
+www.example.com. IN A
+SECTION ANSWER
+www.example.com.       30 IN A 10.1.1.1
+SECTION AUTHORITY
+example.com.           30 IN NS        old-ns.example.com.
+SECTION ADDITIONAL
+old-ns.example.com.    30 IN A 192.168.0.1
+ENTRY_END
+
+STEP 80 TRAFFIC
+; let traffic flow for prefetch to happen
+
+; we updated from the old-ns.
+STEP 90 QUERY
+ENTRY_BEGIN
+REPLY RD
+SECTION QUESTION
+www.example.com. IN A
+ENTRY_END
+; recursion happens here.
+STEP 100 CHECK_ANSWER
+ENTRY_BEGIN
+MATCH all ttl
+REPLY QR RD RA NOERROR
+SECTION QUESTION
+www.example.com. IN A
+SECTION ANSWER
+www.example.com.       300 IN A        10.1.1.1
+SECTION AUTHORITY
+example.com.           30 IN NS        old-ns.example.com.
+SECTION ADDITIONAL
+old-ns.example.com.    300 IN A        192.168.0.1
+ENTRY_END
+
+; the NS record times out after 31 seconds.
+STEP 160 TIME_PASSES ELAPSE 31
+
+; fetch it
+STEP 170 QUERY
+ENTRY_BEGIN
+REPLY RD
+SECTION QUESTION
+www.example.com. IN A
+ENTRY_END
+; recursion happens here.
+STEP 180 CHECK_ANSWER
+ENTRY_BEGIN
+MATCH all ttl
+REPLY QR RD RA NOERROR
+SECTION QUESTION
+www.example.com. IN A
+SECTION ANSWER
+www.example.com.       86400 IN A      10.2.2.2
+SECTION AUTHORITY
+example.com.           86400 IN NS     new-ns.example.com.
+SECTION ADDITIONAL
+new-ns.example.com.    86400 IN A      172.16.0.1
+ENTRY_END
+
+; a reply from cache 
+STEP 190 QUERY
+ENTRY_BEGIN
+REPLY RD
+SECTION QUESTION
+www.example.com. IN A
+ENTRY_END
+; recursion happens here.
+STEP 200 CHECK_ANSWER
+ENTRY_BEGIN
+MATCH all ttl
+REPLY QR RD RA NOERROR
+SECTION QUESTION
+www.example.com. IN A
+SECTION ANSWER
+www.example.com.       86400 IN A      10.2.2.2
+SECTION AUTHORITY
+example.com.           86400 IN NS     new-ns.example.com.
+SECTION ADDITIONAL
+new-ns.example.com.    86400 IN A      172.16.0.1
+ENTRY_END
+
+SCENARIO_END

diff --git a/testdata/iter_prefetch_ns.rpl b/testdata/iter_prefetch_ns.rpl
index 219e48396f97ae2fd60eeed34ca087203f8357ae..0cc528f88b214a82be092d8bdd55517a3eb5ed3e 100644 (file)
--- a/testdata/iter_prefetch_ns.rpl
+++ b/testdata/iter_prefetch_ns.rpl
@@ -11,7 +11,7 @@ CONFIG_END
 SCENARIO_BEGIN Test resolver prefetch of NS record for moved domain
 
 ; K.ROOT-SERVERS.NET.
-RANGE_BEGIN 0 100
+RANGE_BEGIN 0 200
        ADDRESS 193.0.14.129 
 ENTRY_BEGIN
 MATCH opcode qtype qname
@@ -265,6 +265,30 @@ ENTRY_END
 STEP 80 TRAFFIC
 ; let traffic flow for prefetch to happen
 
+; check result of that prefetch
+STEP 90 QUERY
+ENTRY_BEGIN
+REPLY RD
+SECTION QUESTION
+example.com. IN NS
+ENTRY_END
+; recursion happens here.
+STEP 91 CHECK_ANSWER
+ENTRY_BEGIN
+MATCH all ttl
+REPLY QR RD RA NOERROR
+SECTION QUESTION
+example.com. IN NS
+SECTION ANSWER
+; this record is unchanged even though it now points to the
+; new registrant.  Thus it keeps counting down.
+example.com.   360 IN NS       ns.example.com.
+SECTION AUTHORITY
+SECTION ADDITIONAL
+ns.example.com.        3600    IN      A       8.8.8.8
+ENTRY_END
+
+
 ; after 360 + 2000 we are after the change to new owner.
 STEP 100 TIME_PASSES ELAPSE 2360
 
@@ -285,9 +309,9 @@ www.example.com. IN A
 SECTION ANSWER
 www.example.com. 3600 IN A     88.88.88.88
 SECTION AUTHORITY
-example.com.   1240 IN NS      ns.example.com.
+example.com.   3600 IN NS      ns.example.com.
 SECTION ADDITIONAL
-ns.example.com.        820     IN      A       8.8.8.8
+ns.example.com.        1240    IN      A       8.8.8.8
 ENTRY_END
 
 SCENARIO_END