Merge pull request #814 from elsloo/master

Fixes an issue that prevented DNSSEC signatures from being included i…

traffic_router/core/src/main/java/com/comcast/cdn/traffic_control/traffic_router/core/dns/NameServer.java

@@ -23,7 +23,6 @@
 import java.util.List;
 
 import org.apache.log4j.Logger;
-import org.xbill.DNS.CNAMERecord;
 import org.xbill.DNS.DClass;
 import org.xbill.DNS.ExtendedFlags;
 import org.xbill.DNS.Flags;
@@ -224,15 +223,22 @@ private void lookup(final Name qname, final int qtype, final InetAddress clientA
 
 			addAuthority(zone, response, flags);
 		} else if (sr.isCNAME()) {
-			final CNAMERecord cname = sr.getCNAME();
-			final RRset cnameSet = new RRset(cname);
-			addRRset(qname, response, cnameSet, Section.ANSWER, flags);
+			/*
+			 * This is an ugly hack to work around the answers() method not working for CNAMEs.
+			 * A CNAME results in isSuccessful() being false, and answers() requires isSuccessful()
+			 * to be true. Because of this, we can either use reflection (slow) or use the getNS() method, which
+			 * returns the RRset stored internally in "data" and is not actually specific to NS records.
+			 * Our CNAME and RRSIGs are in this RRset, so use getNS() despite its name.
+			 * Refer to the dnsjava SetResponse code for more information.
+			 */
+			final RRset rrset = sr.getNS();
+			addRRset(qname, response, rrset, Section.ANSWER, flags);
 
 			/*
 			 * Allow recursive lookups for CNAME targets; the logic above allows us to
 			 * ensure that we only recurse for domains for which we are authoritative.
 			 */
-			lookup(cname.getTarget(), qtype, clientAddress, zone, response, iteration + 1, flags, dnssecRequest, builder);
+			lookup(sr.getCNAME().getTarget(), qtype, clientAddress, zone, response, iteration + 1, flags, dnssecRequest, builder);
 		} else if (sr.isNXDOMAIN()) {
 			response.getHeader().setRcode(Rcode.NXDOMAIN);
 

traffic_router/core/src/test/java/com/comcast/cdn/traffic_control/traffic_router/core/dns/ZoneManagerTest.java

@@ -16,7 +16,9 @@
 
 package com.comcast.cdn.traffic_control.traffic_router.core.dns;
 
+import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertTrue;
 
 import java.io.File;
 import java.io.FileReader;
@@ -95,6 +97,7 @@ public void testDynamicZoneCache() throws TextParseException, UnknownHostExcepti
 		TrafficRouter trafficRouter = trafficRouterManager.getTrafficRouter();
 		CacheRegister cacheRegister = trafficRouter.getCacheRegister();
 		Map<String, Collection<CacheLocation>> edgeLocations = new HashMap<String, Collection<CacheLocation>>();
+		Set<String> dnsLimited = new HashSet<String>();
 
 		for (Cache c : cacheRegister.getCacheMap().values()) {
 			for (DeliveryServiceReference dsr : c.getDeliveryServices()) {
@@ -103,6 +106,10 @@ public void testDynamicZoneCache() throws TextParseException, UnknownHostExcepti
 				if (!ds.isDns()) continue;
 				final String edgeName = dsr.getFqdn() + ".";
 
+				if (ds.getMaxDnsIps() > 0) {
+					dnsLimited.add(edgeName);
+				}
+
 				if (!edgeLocations.containsKey(edgeName)) {
 					edgeLocations.put(edgeName, new HashSet<CacheLocation>());
 				}
@@ -119,11 +126,52 @@ public void testDynamicZoneCache() throws TextParseException, UnknownHostExcepti
 
 		for (String name : edgeLocations.keySet()) {
 			for (CacheLocation location : edgeLocations.get(name)) {
-				final InetAddress source = netMap.get(location.getId());
 				// need to iterate through the CZF and submit a bunch of these into a job queue to run repeatedly/fast
-				final Zone zone = trafficRouter.getZone(new Name(name), Type.A, source, true, builder);
-				assertNotNull(zone);
-				//LOGGER.info(zone);
+				final InetAddress source = netMap.get(location.getId());
+				final Name n = new Name(name);
+				final Map<Zone, Integer> zoneTracker = new HashMap<Zone, Integer>();
+				final Set<Zone> zones = new HashSet<Zone>();
+				final int seenThreshold = 5;
+
+				while (true) {
+					final Zone zone = trafficRouter.getZone(n, Type.A, source, true, builder); // this should load the zone into the dynamicZoneCache
+					assertNotNull(zone);
+
+					if (!zoneTracker.containsKey(zone)) {
+						zoneTracker.put(zone, 1);
+					} else {
+						final int count = zoneTracker.get(zone);
+						zoneTracker.put(zone, count + 1);
+					}
+
+					if (!dnsLimited.contains(n.toString())) {
+						break;
+					}
+
+					/*
+					 * If we have limits on the number of records, continue building the cache
+					 */
+					boolean allSeen = true;
+
+					for (Integer count : zoneTracker.values()) {
+						if (count < seenThreshold) {
+							allSeen = false;
+							break;
+						}
+					}
+
+					if (allSeen) {
+						break;
+					}
+				}
+
+				zones.addAll(zoneTracker.keySet());
+				//System.out.println("Generated " + zones.size() + " zone(s) for " + n.toString() + " for cache group " + location.getId());
+
+				for (int i = 0; i < 500; i++) {
+					final Zone cachedZone = trafficRouter.getZone(n, Type.A, source, true, builder); // this should be a cache hit
+					assertTrue(zones.contains(cachedZone));
+				}
 			}
 		}
 	}