Put known answers to query packets
To support known-answer suppression, the querier should include
its known answers within each query packet. This allows the
service to determine whether a response is necessary based on
the querier's existing knowledge.
Bug: 312657709
Test: atest FrameworksNetTests NsdManagerTest
Change-Id: I2fb421aff1ae150b310e1a44f50f098a3edb9992
diff --git a/service-t/src/com/android/server/NsdService.java b/service-t/src/com/android/server/NsdService.java
index cfb1a33..aca386f 100644
--- a/service-t/src/com/android/server/NsdService.java
+++ b/service-t/src/com/android/server/NsdService.java
@@ -1851,6 +1851,8 @@
mContext, MdnsFeatureFlags.NSD_UNICAST_REPLY_ENABLED))
.setIsAggressiveQueryModeEnabled(mDeps.isFeatureEnabled(
mContext, MdnsFeatureFlags.NSD_AGGRESSIVE_QUERY_MODE))
+ .setIsQueryWithKnownAnswerEnabled(mDeps.isFeatureEnabled(
+ mContext, MdnsFeatureFlags.NSD_QUERY_WITH_KNOWN_ANSWER))
.setOverrideProvider(flag -> mDeps.isFeatureEnabled(
mContext, FORCE_ENABLE_FLAG_FOR_TEST_PREFIX + flag))
.build();
diff --git a/service-t/src/com/android/server/connectivity/mdns/EnqueueMdnsQueryCallable.java b/service-t/src/com/android/server/connectivity/mdns/EnqueueMdnsQueryCallable.java
index 5537796..e61555a 100644
--- a/service-t/src/com/android/server/connectivity/mdns/EnqueueMdnsQueryCallable.java
+++ b/service-t/src/com/android/server/connectivity/mdns/EnqueueMdnsQueryCallable.java
@@ -23,6 +23,7 @@
import android.text.TextUtils;
import android.util.Pair;
+import com.android.net.module.util.CollectionUtils;
import com.android.net.module.util.SharedLog;
import com.android.server.connectivity.mdns.util.MdnsUtils;
@@ -81,6 +82,8 @@
private final MdnsServiceTypeClient.Dependencies dependencies;
private final boolean onlyUseIpv6OnIpv6OnlyNetworks;
private final byte[] packetCreationBuffer = new byte[1500]; // TODO: use interface MTU
+ @NonNull
+ private final List<MdnsResponse> existingServices;
EnqueueMdnsQueryCallable(
@NonNull MdnsSocketClientBase requestSender,
@@ -94,7 +97,8 @@
@NonNull Collection<MdnsResponse> servicesToResolve,
@NonNull MdnsUtils.Clock clock,
@NonNull SharedLog sharedLog,
- @NonNull MdnsServiceTypeClient.Dependencies dependencies) {
+ @NonNull MdnsServiceTypeClient.Dependencies dependencies,
+ @NonNull Collection<MdnsResponse> existingServices) {
weakRequestSender = new WeakReference<>(requestSender);
serviceTypeLabels = TextUtils.split(serviceType, "\\.");
this.subtypes = new ArrayList<>(subtypes);
@@ -107,6 +111,7 @@
this.clock = clock;
this.sharedLog = sharedLog;
this.dependencies = dependencies;
+ this.existingServices = new ArrayList<>(existingServices);
}
/**
@@ -177,11 +182,34 @@
return Pair.create(INVALID_TRANSACTION_ID, new ArrayList<>());
}
+ // Put the existing ptr records into known-answer section.
+ final List<MdnsRecord> knownAnswers = new ArrayList<>();
+ if (sendDiscoveryQueries) {
+ for (MdnsResponse existingService : existingServices) {
+ for (MdnsPointerRecord ptrRecord : existingService.getPointerRecords()) {
+ // Ignore any PTR records that don't match the current query.
+ if (!CollectionUtils.any(questions,
+ q -> q instanceof MdnsPointerRecord
+ && MdnsUtils.equalsDnsLabelIgnoreDnsCase(
+ q.getName(), ptrRecord.getName()))) {
+ continue;
+ }
+
+ knownAnswers.add(new MdnsPointerRecord(
+ ptrRecord.getName(),
+ ptrRecord.getReceiptTime(),
+ ptrRecord.getCacheFlush(),
+ ptrRecord.getRemainingTTL(now), // Put the remaining ttl.
+ ptrRecord.getPointer()));
+ }
+ }
+ }
+
final MdnsPacket queryPacket = new MdnsPacket(
transactionId,
MdnsConstants.FLAGS_QUERY,
questions,
- Collections.emptyList(), /* answers */
+ knownAnswers,
Collections.emptyList(), /* authorityRecords */
Collections.emptyList() /* additionalRecords */);
sendPacketToIpv4AndIpv6(requestSender, MdnsConstants.MDNS_PORT, queryPacket);
diff --git a/service-t/src/com/android/server/connectivity/mdns/MdnsDiscoveryManager.java b/service-t/src/com/android/server/connectivity/mdns/MdnsDiscoveryManager.java
index 21b7069..7b0c738 100644
--- a/service-t/src/com/android/server/connectivity/mdns/MdnsDiscoveryManager.java
+++ b/service-t/src/com/android/server/connectivity/mdns/MdnsDiscoveryManager.java
@@ -362,7 +362,7 @@
return new MdnsServiceTypeClient(
serviceType, socketClient,
executorProvider.newServiceTypeClientSchedulerExecutor(), socketKey,
- sharedLog.forSubComponent(tag), looper, serviceCache);
+ sharedLog.forSubComponent(tag), looper, serviceCache, mdnsFeatureFlags);
}
/**
diff --git a/service-t/src/com/android/server/connectivity/mdns/MdnsFeatureFlags.java b/service-t/src/com/android/server/connectivity/mdns/MdnsFeatureFlags.java
index 56202fd..f4a08ba 100644
--- a/service-t/src/com/android/server/connectivity/mdns/MdnsFeatureFlags.java
+++ b/service-t/src/com/android/server/connectivity/mdns/MdnsFeatureFlags.java
@@ -62,6 +62,11 @@
*/
public static final String NSD_AGGRESSIVE_QUERY_MODE = "nsd_aggressive_query_mode";
+ /**
+ * A feature flag to control whether the query with known-answer should be enabled.
+ */
+ public static final String NSD_QUERY_WITH_KNOWN_ANSWER = "nsd_query_with_known_answer";
+
// Flag for offload feature
public final boolean mIsMdnsOffloadFeatureEnabled;
@@ -83,6 +88,9 @@
// Flag for aggressive query mode
public final boolean mIsAggressiveQueryModeEnabled;
+ // Flag for query with known-answer
+ public final boolean mIsQueryWithKnownAnswerEnabled;
+
@Nullable
private final FlagOverrideProvider mOverrideProvider;
@@ -126,6 +134,14 @@
}
/**
+ * Indicates whether {@link #NSD_QUERY_WITH_KNOWN_ANSWER} is enabled, including for testing.
+ */
+ public boolean isQueryWithKnownAnswerEnabled() {
+ return mIsQueryWithKnownAnswerEnabled
+ || isForceEnabledForTest(NSD_QUERY_WITH_KNOWN_ANSWER);
+ }
+
+ /**
* The constructor for {@link MdnsFeatureFlags}.
*/
public MdnsFeatureFlags(boolean isOffloadFeatureEnabled,
@@ -135,6 +151,7 @@
boolean isKnownAnswerSuppressionEnabled,
boolean isUnicastReplyEnabled,
boolean isAggressiveQueryModeEnabled,
+ boolean isQueryWithKnownAnswerEnabled,
@Nullable FlagOverrideProvider overrideProvider) {
mIsMdnsOffloadFeatureEnabled = isOffloadFeatureEnabled;
mIncludeInetAddressRecordsInProbing = includeInetAddressRecordsInProbing;
@@ -143,6 +160,7 @@
mIsKnownAnswerSuppressionEnabled = isKnownAnswerSuppressionEnabled;
mIsUnicastReplyEnabled = isUnicastReplyEnabled;
mIsAggressiveQueryModeEnabled = isAggressiveQueryModeEnabled;
+ mIsQueryWithKnownAnswerEnabled = isQueryWithKnownAnswerEnabled;
mOverrideProvider = overrideProvider;
}
@@ -162,6 +180,7 @@
private boolean mIsKnownAnswerSuppressionEnabled;
private boolean mIsUnicastReplyEnabled;
private boolean mIsAggressiveQueryModeEnabled;
+ private boolean mIsQueryWithKnownAnswerEnabled;
private FlagOverrideProvider mOverrideProvider;
/**
@@ -175,6 +194,7 @@
mIsKnownAnswerSuppressionEnabled = false;
mIsUnicastReplyEnabled = true;
mIsAggressiveQueryModeEnabled = false;
+ mIsQueryWithKnownAnswerEnabled = false;
mOverrideProvider = null;
}
@@ -261,6 +281,16 @@
}
/**
+ * Set whether the query with known-answer is enabled.
+ *
+ * @see #NSD_QUERY_WITH_KNOWN_ANSWER
+ */
+ public Builder setIsQueryWithKnownAnswerEnabled(boolean isQueryWithKnownAnswerEnabled) {
+ mIsQueryWithKnownAnswerEnabled = isQueryWithKnownAnswerEnabled;
+ return this;
+ }
+
+ /**
* Builds a {@link MdnsFeatureFlags} with the arguments supplied to this builder.
*/
public MdnsFeatureFlags build() {
@@ -271,6 +301,7 @@
mIsKnownAnswerSuppressionEnabled,
mIsUnicastReplyEnabled,
mIsAggressiveQueryModeEnabled,
+ mIsQueryWithKnownAnswerEnabled,
mOverrideProvider);
}
}
diff --git a/service-t/src/com/android/server/connectivity/mdns/MdnsServiceTypeClient.java b/service-t/src/com/android/server/connectivity/mdns/MdnsServiceTypeClient.java
index ba6cdd5..bfcd0b4 100644
--- a/service-t/src/com/android/server/connectivity/mdns/MdnsServiceTypeClient.java
+++ b/service-t/src/com/android/server/connectivity/mdns/MdnsServiceTypeClient.java
@@ -86,6 +86,7 @@
notifyRemovedServiceToListeners(previousResponse, "Service record expired");
}
};
+ @NonNull private final MdnsFeatureFlags featureFlags;
private final ArrayMap<MdnsServiceBrowserListener, ListenerInfo> listeners =
new ArrayMap<>();
private final boolean removeServiceAfterTtlExpires =
@@ -144,7 +145,8 @@
// before sending the query, it needs to be called just before sending it.
final List<MdnsResponse> servicesToResolve = makeResponsesForResolve(socketKey);
final QueryTask queryTask = new QueryTask(taskArgs, servicesToResolve,
- getAllDiscoverySubtypes(), needSendDiscoveryQueries(listeners));
+ getAllDiscoverySubtypes(), needSendDiscoveryQueries(listeners),
+ getExistingServices());
executor.submit(queryTask);
break;
}
@@ -248,9 +250,10 @@
@NonNull SocketKey socketKey,
@NonNull SharedLog sharedLog,
@NonNull Looper looper,
- @NonNull MdnsServiceCache serviceCache) {
+ @NonNull MdnsServiceCache serviceCache,
+ @NonNull MdnsFeatureFlags featureFlags) {
this(serviceType, socketClient, executor, new Clock(), socketKey, sharedLog, looper,
- new Dependencies(), serviceCache);
+ new Dependencies(), serviceCache, featureFlags);
}
@VisibleForTesting
@@ -263,7 +266,8 @@
@NonNull SharedLog sharedLog,
@NonNull Looper looper,
@NonNull Dependencies dependencies,
- @NonNull MdnsServiceCache serviceCache) {
+ @NonNull MdnsServiceCache serviceCache,
+ @NonNull MdnsFeatureFlags featureFlags) {
this.serviceType = serviceType;
this.socketClient = socketClient;
this.executor = executor;
@@ -277,6 +281,7 @@
this.serviceCache = serviceCache;
this.mdnsQueryScheduler = new MdnsQueryScheduler();
this.cacheKey = new MdnsServiceCache.CacheKey(serviceType, socketKey);
+ this.featureFlags = featureFlags;
}
/**
@@ -339,6 +344,11 @@
now.plusMillis(response.getMinRemainingTtl(now.toEpochMilli())));
}
+ private List<MdnsResponse> getExistingServices() {
+ return featureFlags.isQueryWithKnownAnswerEnabled()
+ ? serviceCache.getCachedServices(cacheKey) : Collections.emptyList();
+ }
+
/**
* Registers {@code listener} for receiving discovery event of mDNS service instances, and
* starts
@@ -403,7 +413,8 @@
final QueryTask queryTask = new QueryTask(
mdnsQueryScheduler.scheduleFirstRun(taskConfig, now,
minRemainingTtl, currentSessionId), servicesToResolve,
- getAllDiscoverySubtypes(), needSendDiscoveryQueries(listeners));
+ getAllDiscoverySubtypes(), needSendDiscoveryQueries(listeners),
+ getExistingServices());
executor.submit(queryTask);
}
@@ -701,14 +712,16 @@
private final List<MdnsResponse> servicesToResolve = new ArrayList<>();
private final List<String> subtypes = new ArrayList<>();
private final boolean sendDiscoveryQueries;
+ private final List<MdnsResponse> existingServices = new ArrayList<>();
QueryTask(@NonNull MdnsQueryScheduler.ScheduledQueryTaskArgs taskArgs,
@NonNull Collection<MdnsResponse> servicesToResolve,
- @NonNull Collection<String> subtypes,
- boolean sendDiscoveryQueries) {
+ @NonNull Collection<String> subtypes, boolean sendDiscoveryQueries,
+ @NonNull Collection<MdnsResponse> existingServices) {
this.taskArgs = taskArgs;
this.servicesToResolve.addAll(servicesToResolve);
this.subtypes.addAll(subtypes);
this.sendDiscoveryQueries = sendDiscoveryQueries;
+ this.existingServices.addAll(existingServices);
}
@Override
@@ -728,7 +741,8 @@
servicesToResolve,
clock,
sharedLog,
- dependencies)
+ dependencies,
+ existingServices)
.call();
} catch (RuntimeException e) {
sharedLog.e(String.format("Failed to run EnqueueMdnsQueryCallable for subtype: %s",
diff --git a/tests/cts/net/src/android/net/cts/NsdManagerTest.kt b/tests/cts/net/src/android/net/cts/NsdManagerTest.kt
index 8dbcf2f..3f72395 100644
--- a/tests/cts/net/src/android/net/cts/NsdManagerTest.kt
+++ b/tests/cts/net/src/android/net/cts/NsdManagerTest.kt
@@ -1888,6 +1888,64 @@
}
}
+ @Test
+ fun testQueryWhenKnownAnswerSuppressionFlagSet() {
+ // The flag may be removed in the future but known-answer suppression should be enabled by
+ // default in that case. The rule will reset flags automatically on teardown.
+ deviceConfigRule.setConfig(NAMESPACE_TETHERING, "test_nsd_query_with_known_answer", "1")
+
+ // Register service on testNetwork1
+ val discoveryRecord = NsdDiscoveryRecord()
+ val packetReader = TapPacketReader(Handler(handlerThread.looper),
+ testNetwork1.iface.fileDescriptor.fileDescriptor, 1500 /* maxPacketSize */)
+ packetReader.startAsyncForTest()
+ handlerThread.waitForIdle(TIMEOUT_MS)
+
+ nsdManager.discoverServices(serviceType, NsdManager.PROTOCOL_DNS_SD,
+ testNetwork1.network, { it.run() }, discoveryRecord)
+
+ tryTest {
+ discoveryRecord.expectCallback<DiscoveryStarted>()
+ assertNotNull(packetReader.pollForQuery("$serviceType.local", DnsResolver.TYPE_PTR))
+ /*
+ Generated with:
+ scapy.raw(scapy.DNS(rd=0, qr=1, aa=1, qd = None, an =
+ scapy.DNSRR(rrname='_nmt123456789._tcp.local', type='PTR', ttl=120,
+ rdata='NsdTest123456789._nmt123456789._tcp.local'))).hex()
+ */
+ val ptrResponsePayload = HexDump.hexStringToByteArray("0000840000000001000000000d5f6e" +
+ "6d74313233343536373839045f746370056c6f63616c00000c000100000078002b104e736454" +
+ "6573743132333435363738390d5f6e6d74313233343536373839045f746370056c6f63616c00")
+
+ replaceServiceNameAndTypeWithTestSuffix(ptrResponsePayload)
+ packetReader.sendResponse(buildMdnsPacket(ptrResponsePayload))
+
+ val serviceFound = discoveryRecord.expectCallback<ServiceFound>()
+ serviceFound.serviceInfo.let {
+ assertEquals(serviceName, it.serviceName)
+ // Discovered service types have a dot at the end
+ assertEquals("$serviceType.", it.serviceType)
+ assertEquals(testNetwork1.network, it.network)
+ // ServiceFound does not provide port, address or attributes (only information
+ // available in the PTR record is included in that callback, regardless of whether
+ // other records exist).
+ assertEquals(0, it.port)
+ assertEmpty(it.hostAddresses)
+ assertEquals(0, it.attributes.size)
+ }
+
+ // Expect the second query with a known answer
+ val query = packetReader.pollForMdnsPacket { pkt ->
+ pkt.isQueryFor("$serviceType.local", DnsResolver.TYPE_PTR) &&
+ pkt.isReplyFor("$serviceType.local", DnsResolver.TYPE_PTR)
+ }
+ assertNotNull(query)
+ } cleanup {
+ nsdManager.stopServiceDiscovery(discoveryRecord)
+ discoveryRecord.expectCallback<DiscoveryStopped>()
+ }
+ }
+
private fun makeLinkLocalAddressOfOtherDeviceOnPrefix(network: Network): Inet6Address {
val lp = cm.getLinkProperties(network) ?: fail("No LinkProperties for net $network")
// Expect to have a /64 link-local address
diff --git a/tests/unit/java/com/android/server/connectivity/mdns/MdnsServiceTypeClientTests.java b/tests/unit/java/com/android/server/connectivity/mdns/MdnsServiceTypeClientTests.java
index b1df7f8..2eb9440 100644
--- a/tests/unit/java/com/android/server/connectivity/mdns/MdnsServiceTypeClientTests.java
+++ b/tests/unit/java/com/android/server/connectivity/mdns/MdnsServiceTypeClientTests.java
@@ -144,6 +144,7 @@
private long latestDelayMs = 0;
private Message delayMessage = null;
private Handler realHandler = null;
+ private MdnsFeatureFlags featureFlags = MdnsFeatureFlags.newBuilder().build();
@Before
@SuppressWarnings("DoNotMock")
@@ -249,7 +250,7 @@
private MdnsServiceTypeClient makeMdnsServiceTypeClient() {
return new MdnsServiceTypeClient(SERVICE_TYPE, mockSocketClient, currentThreadExecutor,
mockDecoderClock, socketKey, mockSharedLog, thread.getLooper(), mockDeps,
- serviceCache);
+ serviceCache, featureFlags);
}
@After
@@ -1929,6 +1930,138 @@
16 /* scheduledCount */);
}
+ @Test
+ public void testSendQueryWithKnownAnswers() throws Exception {
+ client = new MdnsServiceTypeClient(SERVICE_TYPE, mockSocketClient, currentThreadExecutor,
+ mockDecoderClock, socketKey, mockSharedLog, thread.getLooper(), mockDeps,
+ serviceCache,
+ MdnsFeatureFlags.newBuilder().setIsQueryWithKnownAnswerEnabled(true).build());
+
+ doCallRealMethod().when(mockDeps).getDatagramPacketFromMdnsPacket(
+ any(), any(MdnsPacket.class), any(InetSocketAddress.class));
+
+ startSendAndReceive(mockListenerOne, MdnsSearchOptions.getDefaultOptions());
+ InOrder inOrder = inOrder(mockListenerOne, mockSocketClient);
+
+ final ArgumentCaptor<DatagramPacket> queryCaptor =
+ ArgumentCaptor.forClass(DatagramPacket.class);
+ currentThreadExecutor.getAndClearLastScheduledRunnable().run();
+ // Send twice for IPv4 and IPv6
+ inOrder.verify(mockSocketClient, times(2)).sendPacketRequestingUnicastResponse(
+ queryCaptor.capture(), eq(socketKey), eq(false));
+ verify(mockDeps, times(1)).sendMessage(any(), any(Message.class));
+ assertNotNull(delayMessage);
+
+ final MdnsPacket queryPacket = MdnsPacket.parse(
+ new MdnsPacketReader(queryCaptor.getValue()));
+ assertTrue(hasQuestion(queryPacket, MdnsRecord.TYPE_PTR));
+
+ // Process a response
+ final String serviceName = "service-instance";
+ final String ipV4Address = "192.0.2.0";
+ final String[] subtypeLabels = Stream.concat(Stream.of("_subtype", "_sub"),
+ Arrays.stream(SERVICE_TYPE_LABELS)).toArray(String[]::new);
+ final MdnsPacket packetWithoutSubtype = createResponse(
+ serviceName, ipV4Address, 5353, SERVICE_TYPE_LABELS,
+ Collections.emptyMap() /* textAttributes */, TEST_TTL);
+ final MdnsPointerRecord originalPtr = (MdnsPointerRecord) CollectionUtils.findFirst(
+ packetWithoutSubtype.answers, r -> r instanceof MdnsPointerRecord);
+
+ // Add a subtype PTR record
+ final ArrayList<MdnsRecord> newAnswers = new ArrayList<>(packetWithoutSubtype.answers);
+ newAnswers.add(new MdnsPointerRecord(subtypeLabels, originalPtr.getReceiptTime(),
+ originalPtr.getCacheFlush(), originalPtr.getTtl(), originalPtr.getPointer()));
+ final MdnsPacket packetWithSubtype = new MdnsPacket(
+ packetWithoutSubtype.flags,
+ packetWithoutSubtype.questions,
+ newAnswers,
+ packetWithoutSubtype.authorityRecords,
+ packetWithoutSubtype.additionalRecords);
+ processResponse(packetWithSubtype, socketKey);
+
+ // Expect a query with known answers
+ dispatchMessage();
+ final ArgumentCaptor<DatagramPacket> knownAnswersQueryCaptor =
+ ArgumentCaptor.forClass(DatagramPacket.class);
+ currentThreadExecutor.getAndClearLastScheduledRunnable().run();
+ inOrder.verify(mockSocketClient, times(2)).sendPacketRequestingMulticastResponse(
+ knownAnswersQueryCaptor.capture(), eq(socketKey), eq(false));
+
+ final MdnsPacket knownAnswersQueryPacket = MdnsPacket.parse(
+ new MdnsPacketReader(knownAnswersQueryCaptor.getValue()));
+ assertTrue(hasQuestion(knownAnswersQueryPacket, MdnsRecord.TYPE_PTR, SERVICE_TYPE_LABELS));
+ assertTrue(hasAnswer(knownAnswersQueryPacket, MdnsRecord.TYPE_PTR, SERVICE_TYPE_LABELS));
+ assertFalse(hasAnswer(knownAnswersQueryPacket, MdnsRecord.TYPE_PTR, subtypeLabels));
+ }
+
+ @Test
+ public void testSendQueryWithSubTypeWithKnownAnswers() throws Exception {
+ client = new MdnsServiceTypeClient(SERVICE_TYPE, mockSocketClient, currentThreadExecutor,
+ mockDecoderClock, socketKey, mockSharedLog, thread.getLooper(), mockDeps,
+ serviceCache,
+ MdnsFeatureFlags.newBuilder().setIsQueryWithKnownAnswerEnabled(true).build());
+
+ doCallRealMethod().when(mockDeps).getDatagramPacketFromMdnsPacket(
+ any(), any(MdnsPacket.class), any(InetSocketAddress.class));
+
+ final MdnsSearchOptions options = MdnsSearchOptions.newBuilder()
+ .addSubtype("subtype").build();
+ startSendAndReceive(mockListenerOne, options);
+ InOrder inOrder = inOrder(mockListenerOne, mockSocketClient);
+
+ final ArgumentCaptor<DatagramPacket> queryCaptor =
+ ArgumentCaptor.forClass(DatagramPacket.class);
+ currentThreadExecutor.getAndClearLastScheduledRunnable().run();
+ // Send twice for IPv4 and IPv6
+ inOrder.verify(mockSocketClient, times(2)).sendPacketRequestingUnicastResponse(
+ queryCaptor.capture(), eq(socketKey), eq(false));
+ verify(mockDeps, times(1)).sendMessage(any(), any(Message.class));
+ assertNotNull(delayMessage);
+
+ final MdnsPacket queryPacket = MdnsPacket.parse(
+ new MdnsPacketReader(queryCaptor.getValue()));
+ final String[] subtypeLabels = Stream.concat(Stream.of("_subtype", "_sub"),
+ Arrays.stream(SERVICE_TYPE_LABELS)).toArray(String[]::new);
+ assertTrue(hasQuestion(queryPacket, MdnsRecord.TYPE_PTR, SERVICE_TYPE_LABELS));
+ assertTrue(hasQuestion(queryPacket, MdnsRecord.TYPE_PTR, subtypeLabels));
+
+ // Process a response
+ final String serviceName = "service-instance";
+ final String ipV4Address = "192.0.2.0";
+ final MdnsPacket packetWithoutSubtype = createResponse(
+ serviceName, ipV4Address, 5353, SERVICE_TYPE_LABELS,
+ Collections.emptyMap() /* textAttributes */, TEST_TTL);
+ final MdnsPointerRecord originalPtr = (MdnsPointerRecord) CollectionUtils.findFirst(
+ packetWithoutSubtype.answers, r -> r instanceof MdnsPointerRecord);
+
+ // Add a subtype PTR record
+ final ArrayList<MdnsRecord> newAnswers = new ArrayList<>(packetWithoutSubtype.answers);
+ newAnswers.add(new MdnsPointerRecord(subtypeLabels, originalPtr.getReceiptTime(),
+ originalPtr.getCacheFlush(), originalPtr.getTtl(), originalPtr.getPointer()));
+ final MdnsPacket packetWithSubtype = new MdnsPacket(
+ packetWithoutSubtype.flags,
+ packetWithoutSubtype.questions,
+ newAnswers,
+ packetWithoutSubtype.authorityRecords,
+ packetWithoutSubtype.additionalRecords);
+ processResponse(packetWithSubtype, socketKey);
+
+ // Expect a query with known answers
+ dispatchMessage();
+ final ArgumentCaptor<DatagramPacket> knownAnswersQueryCaptor =
+ ArgumentCaptor.forClass(DatagramPacket.class);
+ currentThreadExecutor.getAndClearLastScheduledRunnable().run();
+ inOrder.verify(mockSocketClient, times(2)).sendPacketRequestingMulticastResponse(
+ knownAnswersQueryCaptor.capture(), eq(socketKey), eq(false));
+
+ final MdnsPacket knownAnswersQueryPacket = MdnsPacket.parse(
+ new MdnsPacketReader(knownAnswersQueryCaptor.getValue()));
+ assertTrue(hasQuestion(knownAnswersQueryPacket, MdnsRecord.TYPE_PTR, SERVICE_TYPE_LABELS));
+ assertTrue(hasQuestion(knownAnswersQueryPacket, MdnsRecord.TYPE_PTR, subtypeLabels));
+ assertTrue(hasAnswer(knownAnswersQueryPacket, MdnsRecord.TYPE_PTR, SERVICE_TYPE_LABELS));
+ assertTrue(hasAnswer(knownAnswersQueryPacket, MdnsRecord.TYPE_PTR, subtypeLabels));
+ }
+
private static MdnsServiceInfo matchServiceName(String name) {
return argThat(info -> info.getServiceInstanceName().equals(name));
}
@@ -1989,6 +2122,12 @@
&& (name == null || Arrays.equals(q.name, name)));
}
+ private static boolean hasAnswer(MdnsPacket packet, int type, @NonNull String[] name) {
+ return packet.answers.stream().anyMatch(q -> {
+ return q.getType() == type && (Arrays.equals(q.name, name));
+ });
+ }
+
// A fake ScheduledExecutorService that keeps tracking the last scheduled Runnable and its delay
// time.
private class FakeExecutor extends ScheduledThreadPoolExecutor {