Rec: test that an ImmediateServFailException isn't hidden by the serve-stale logic

(cherry picked from commit 60a0965f82283249e8f054afe474adc33a57b8bc)

diff --git a/pdns/recursordist/test-syncres_cc10.cc b/pdns/recursordist/test-syncres_cc10.cc
index dce931b9da73d586be42e68e52ee5d590cff2670..f3a41f9de1f5769178fea92edacfb167242be692 100644 (file)
--- a/pdns/recursordist/test-syncres_cc10.cc
+++ b/pdns/recursordist/test-syncres_cc10.cc
@@ -1628,6 +1628,85 @@ BOOST_AUTO_TEST_CASE(test_servestale_cname_to_nxdomain)
   BOOST_CHECK_EQUAL(lookupCount, 3U);
 }
 
+BOOST_AUTO_TEST_CASE(test_servestale_immediateservfail)
+{
+  std::unique_ptr<SyncRes> sr;
+  initSR(sr);
+  MemRecursorCache::s_maxServedStaleExtensions = 1440;
+
+  primeHints();
+
+  const DNSName target("powerdns.com.");
+
+  std::set<ComboAddress> downServers;
+  size_t downCount = 0;
+  size_t lookupCount = 0;
+
+  const int theTTL = 5;
+
+  sr->setAsyncCallback([&downServers, &downCount, &lookupCount, target](const ComboAddress& ip, const DNSName& domain, int type, bool doTCP, bool sendRDQuery, int EDNS0Level, struct timeval* now, boost::optional<Netmask>& srcmask, boost::optional<const ResolveContext&> context, LWResult* res, bool* chained) {
+    /* this will cause issue with qname minimization if we ever implement it */
+
+    if (downServers.find(ip) != downServers.end()) {
+      downCount++;
+      throw ImmediateServFailException("FAIL!");
+    }
+
+    if (isRootServer(ip)) {
+      setLWResult(res, 0, false, false, true);
+      addRecordToLW(res, "com.", QType::NS, "a.gtld-servers.net.", DNSResourceRecord::AUTHORITY);
+      addRecordToLW(res, "a.gtld-servers.net.", QType::A, "192.0.2.1", DNSResourceRecord::ADDITIONAL);
+      addRecordToLW(res, "a.gtld-servers.net.", QType::AAAA, "2001:DB8::1", DNSResourceRecord::ADDITIONAL);
+      return LWResult::Result::Success;
+    }
+    else if (ip == ComboAddress("192.0.2.1:53") || ip == ComboAddress("[2001:DB8::1]:53")) {
+      setLWResult(res, 0, false, false, true);
+      addRecordToLW(res, "powerdns.com.", QType::NS, "pdns-public-ns1.powerdns.com.", DNSResourceRecord::AUTHORITY, theTTL);
+      addRecordToLW(res, "powerdns.com.", QType::NS, "pdns-public-ns2.powerdns.com.", DNSResourceRecord::AUTHORITY, theTTL);
+      addRecordToLW(res, "pdns-public-ns1.powerdns.com.", QType::A, "192.0.2.2", DNSResourceRecord::ADDITIONAL, 5);
+      addRecordToLW(res, "pdns-public-ns1.powerdns.com.", QType::AAAA, "2001:DB8::2", DNSResourceRecord::ADDITIONAL, theTTL);
+      addRecordToLW(res, "pdns-public-ns2.powerdns.com.", QType::A, "192.0.2.3", DNSResourceRecord::ADDITIONAL, 5);
+      addRecordToLW(res, "pdns-public-ns2.powerdns.com.", QType::AAAA, "2001:DB8::3", DNSResourceRecord::ADDITIONAL, theTTL);
+      return LWResult::Result::Success;
+    }
+    else if (ip == ComboAddress("192.0.2.2:53") || ip == ComboAddress("192.0.2.3:53") || ip == ComboAddress("[2001:DB8::2]:53") || ip == ComboAddress("[2001:DB8::3]:53")) {
+      setLWResult(res, 0, true, false, true);
+      addRecordToLW(res, target, QType::A, "192.0.2.4", DNSResourceRecord::ANSWER, 5);
+      lookupCount++;
+      return LWResult::Result::Success;
+    }
+    else {
+      return LWResult::Result::Timeout;
+    }
+  });
+
+  time_t now = time(nullptr);
+
+  vector<DNSRecord> ret;
+  int res = sr->beginResolve(target, QType(QType::A), QClass::IN, ret);
+
+  BOOST_CHECK_EQUAL(res, RCode::NoError);
+  BOOST_REQUIRE_EQUAL(ret.size(), 1U);
+  BOOST_CHECK(ret[0].d_type == QType::A);
+  BOOST_CHECK_EQUAL(ret[0].d_name, target);
+  BOOST_CHECK_EQUAL(downCount, 0U);
+  BOOST_CHECK_EQUAL(lookupCount, 1U);
+
+  downServers.insert(ComboAddress("192.0.2.2:53"));
+  downServers.insert(ComboAddress("192.0.2.3:53"));
+  downServers.insert(ComboAddress("[2001:DB8::2]:53"));
+  downServers.insert(ComboAddress("[2001:DB8::3]:53"));
+
+  sr->setNow(timeval{now + theTTL + 1, 0});
+
+  BOOST_REQUIRE_EQUAL(getTaskSize(), 0U);
+
+  // record is expired, so serve stale should kick in
+  ret.clear();
+  BOOST_REQUIRE_THROW(sr->beginResolve(target, QType(QType::A), QClass::IN, ret), ImmediateServFailException);
+  BOOST_CHECK_EQUAL(downCount, 1U);
+}
+
 BOOST_AUTO_TEST_CASE(test_glued_referral_additional_update)
 {
   // Test that additional records update the cache