Merge "[mdns] restart probing/announcing the services on host address removal" into main
diff --git a/service-t/src/com/android/server/connectivity/mdns/MdnsInterfaceAdvertiser.java b/service-t/src/com/android/server/connectivity/mdns/MdnsInterfaceAdvertiser.java
index c1c7d5f..61eb766 100644
--- a/service-t/src/com/android/server/connectivity/mdns/MdnsInterfaceAdvertiser.java
+++ b/service-t/src/com/android/server/connectivity/mdns/MdnsInterfaceAdvertiser.java
@@ -22,12 +22,10 @@
 import android.annotation.Nullable;
 import android.annotation.RequiresApi;
 import android.net.LinkAddress;
-import android.net.nsd.NsdManager;
 import android.net.nsd.NsdServiceInfo;
 import android.os.Build;
 import android.os.Handler;
 import android.os.Looper;
-import android.util.ArraySet;
 
 import com.android.internal.annotations.VisibleForTesting;
 import com.android.net.module.util.HexDump;
@@ -284,6 +282,7 @@
         if (!mRecordRepository.hasActiveService(id)) return;
         mProber.stop(id);
         mAnnouncer.stop(id);
+        final String hostname = mRecordRepository.getHostnameForServiceId(id);
         final MdnsAnnouncer.ExitAnnouncementInfo exitInfo = mRecordRepository.exitService(id);
         if (exitInfo != null) {
             // This effectively schedules onAllServicesRemoved(), as it is to be called when the
@@ -303,6 +302,24 @@
                 }
             });
         }
+        // Re-probe/re-announce the services which have the same custom hostname. These services
+        // were probed/announced using host addresses which were just removed so they should be
+        // re-probed/re-announced without those addresses.
+        if (hostname != null) {
+            final List<MdnsProber.ProbingInfo> probingInfos =
+                    mRecordRepository.restartProbingForHostname(hostname);
+            for (MdnsProber.ProbingInfo probingInfo : probingInfos) {
+                mProber.stop(probingInfo.getServiceId());
+                mProber.startProbing(probingInfo);
+            }
+            final List<MdnsAnnouncer.AnnouncementInfo> announcementInfos =
+                    mRecordRepository.restartAnnouncingForHostname(hostname);
+            for (MdnsAnnouncer.AnnouncementInfo announcementInfo : announcementInfos) {
+                mAnnouncer.stop(announcementInfo.getServiceId());
+                mAnnouncer.startSending(
+                        announcementInfo.getServiceId(), announcementInfo, 0 /* initialDelayMs */);
+            }
+        }
     }
 
     /**
diff --git a/service-t/src/com/android/server/connectivity/mdns/MdnsRecordRepository.java b/service-t/src/com/android/server/connectivity/mdns/MdnsRecordRepository.java
index ac64c3a..073e465 100644
--- a/service-t/src/com/android/server/connectivity/mdns/MdnsRecordRepository.java
+++ b/service-t/src/com/android/server/connectivity/mdns/MdnsRecordRepository.java
@@ -925,22 +925,79 @@
         }
     }
 
+    @Nullable
+    public String getHostnameForServiceId(int id) {
+        ServiceRegistration registration = mServices.get(id);
+        if (registration == null) {
+            return null;
+        }
+        return registration.serviceInfo.getHostname();
+    }
+
+    /**
+     * Restart probing the services which are being probed and using the given custom hostname.
+     *
+     * @return The list of {@link MdnsProber.ProbingInfo} to be used by advertiser.
+     */
+    public List<MdnsProber.ProbingInfo> restartProbingForHostname(@NonNull String hostname) {
+        final ArrayList<MdnsProber.ProbingInfo> probingInfos = new ArrayList<>();
+        forEachActiveServiceRegistrationWithHostname(
+                hostname,
+                (id, registration) -> {
+                    if (!registration.isProbing) {
+                        return;
+                    }
+                    probingInfos.add(makeProbingInfo(id, registration));
+                });
+        return probingInfos;
+    }
+
+    /**
+     * Restart announcing the services which are using the given custom hostname.
+     *
+     * @return The list of {@link MdnsAnnouncer.AnnouncementInfo} to be used by advertiser.
+     */
+    public List<MdnsAnnouncer.AnnouncementInfo> restartAnnouncingForHostname(
+            @NonNull String hostname) {
+        final ArrayList<MdnsAnnouncer.AnnouncementInfo> announcementInfos = new ArrayList<>();
+        forEachActiveServiceRegistrationWithHostname(
+                hostname,
+                (id, registration) -> {
+                    if (registration.isProbing) {
+                        return;
+                    }
+                    announcementInfos.add(makeAnnouncementInfo(id, registration));
+                });
+        return announcementInfos;
+    }
+
     /**
      * Called to indicate that probing succeeded for a service.
+     *
      * @param probeSuccessInfo The successful probing info.
      * @return The {@link MdnsAnnouncer.AnnouncementInfo} to send, now that probing has succeeded.
      */
     public MdnsAnnouncer.AnnouncementInfo onProbingSucceeded(
-            MdnsProber.ProbingInfo probeSuccessInfo)
-            throws IOException {
-
-        int serviceId = probeSuccessInfo.getServiceId();
+            MdnsProber.ProbingInfo probeSuccessInfo) throws IOException {
+        final int serviceId = probeSuccessInfo.getServiceId();
         final ServiceRegistration registration = mServices.get(serviceId);
         if (registration == null) {
             throw new IOException("Service is not registered: " + serviceId);
         }
         registration.setProbing(false);
 
+        return makeAnnouncementInfo(serviceId, registration);
+    }
+
+    /**
+     * Make the announcement info of the given service ID.
+     *
+     * @param serviceId The service ID.
+     * @param registration The service registration.
+     * @return The {@link MdnsAnnouncer.AnnouncementInfo} of the given service ID.
+     */
+    private MdnsAnnouncer.AnnouncementInfo makeAnnouncementInfo(
+            int serviceId, ServiceRegistration registration) {
         final Set<MdnsRecord> answersSet = new LinkedHashSet<>();
         final ArrayList<MdnsRecord> additionalAnswers = new ArrayList<>();
 
@@ -972,8 +1029,8 @@
         addNsecRecordsForUniqueNames(additionalAnswers,
                 mGeneralRecords.iterator(), registration.allRecords.iterator());
 
-        return new MdnsAnnouncer.AnnouncementInfo(
-                probeSuccessInfo.getServiceId(), new ArrayList<>(answersSet), additionalAnswers);
+        return new MdnsAnnouncer.AnnouncementInfo(serviceId,
+                new ArrayList<>(answersSet), additionalAnswers);
     }
 
     /**
diff --git a/tests/cts/net/src/android/net/cts/NsdManagerTest.kt b/tests/cts/net/src/android/net/cts/NsdManagerTest.kt
index 61117df..6dd4857 100644
--- a/tests/cts/net/src/android/net/cts/NsdManagerTest.kt
+++ b/tests/cts/net/src/android/net/cts/NsdManagerTest.kt
@@ -2206,6 +2206,66 @@
     }
 
     @Test
+    fun testAdvertisingAndDiscovery_reregisterCustomHostWithDifferentAddresses_newAddressesFound() {
+        val si1 = NsdServiceInfo().also {
+            it.network = testNetwork1.network
+            it.hostname = customHostname
+            it.hostAddresses = listOf(
+                    parseNumericAddress("192.0.2.23"),
+                    parseNumericAddress("2001:db8::1"))
+        }
+        val si2 = NsdServiceInfo().also {
+            it.network = testNetwork1.network
+            it.serviceName = serviceName
+            it.serviceType = serviceType
+            it.hostname = customHostname
+            it.port = TEST_PORT
+        }
+        val si3 = NsdServiceInfo().also {
+            it.network = testNetwork1.network
+            it.hostname = customHostname
+            it.hostAddresses = listOf(
+                    parseNumericAddress("192.0.2.24"),
+                    parseNumericAddress("2001:db8::2"))
+        }
+
+        val registrationRecord1 = NsdRegistrationRecord()
+        val registrationRecord2 = NsdRegistrationRecord()
+        val registrationRecord3 = NsdRegistrationRecord()
+
+        val discoveryRecord = NsdDiscoveryRecord()
+
+        tryTest {
+            registerService(registrationRecord1, si1)
+            registerService(registrationRecord2, si2)
+
+            nsdManager.unregisterService(registrationRecord1)
+            registrationRecord1.expectCallback<ServiceUnregistered>()
+
+            registerService(registrationRecord3, si3)
+
+            nsdManager.discoverServices(serviceType, NsdManager.PROTOCOL_DNS_SD,
+                    testNetwork1.network, Executor { it.run() }, discoveryRecord)
+            val discoveredInfo = discoveryRecord.waitForServiceDiscovered(
+                    serviceName, serviceType, testNetwork1.network)
+            val resolvedInfo = resolveService(discoveredInfo)
+
+            assertEquals(serviceName, discoveredInfo.serviceName)
+            assertEquals(TEST_PORT, resolvedInfo.port)
+            assertEquals(customHostname, resolvedInfo.hostname)
+            assertAddressEquals(
+                    listOf(parseNumericAddress("192.0.2.24"), parseNumericAddress("2001:db8::2")),
+                    resolvedInfo.hostAddresses)
+        } cleanupStep {
+            nsdManager.stopServiceDiscovery(discoveryRecord)
+            discoveryRecord.expectCallbackEventually<DiscoveryStopped>()
+        } cleanup {
+            nsdManager.unregisterService(registrationRecord2)
+            nsdManager.unregisterService(registrationRecord3)
+        }
+    }
+
+    @Test
     fun testServiceTypeClientRemovedAfterSocketDestroyed() {
         val si = makeTestServiceInfo(testNetwork1.network)
         // Register service on testNetwork1
diff --git a/tests/unit/java/com/android/server/connectivity/mdns/MdnsInterfaceAdvertiserTest.kt b/tests/unit/java/com/android/server/connectivity/mdns/MdnsInterfaceAdvertiserTest.kt
index 69fec85..7ac7bee 100644
--- a/tests/unit/java/com/android/server/connectivity/mdns/MdnsInterfaceAdvertiserTest.kt
+++ b/tests/unit/java/com/android/server/connectivity/mdns/MdnsInterfaceAdvertiserTest.kt
@@ -18,7 +18,6 @@
 
 import android.net.InetAddresses.parseNumericAddress
 import android.net.LinkAddress
-import android.net.nsd.NsdManager
 import android.net.nsd.NsdServiceInfo
 import android.os.Build
 import android.os.HandlerThread
@@ -48,6 +47,7 @@
 import org.mockito.Mockito.anyInt
 import org.mockito.Mockito.anyString
 import org.mockito.Mockito.argThat
+import org.mockito.Mockito.atLeastOnce
 import org.mockito.Mockito.doAnswer
 import org.mockito.Mockito.doReturn
 import org.mockito.Mockito.eq
@@ -55,6 +55,8 @@
 import org.mockito.Mockito.never
 import org.mockito.Mockito.times
 import org.mockito.Mockito.verify
+import org.mockito.Mockito.clearInvocations
+import org.mockito.Mockito.inOrder
 
 private const val LOG_TAG = "testlogtag"
 private const val TIMEOUT_MS = 10_000L
@@ -65,6 +67,7 @@
 
 private const val TEST_SERVICE_ID_1 = 42
 private const val TEST_SERVICE_ID_DUPLICATE = 43
+private const val TEST_SERVICE_ID_2 = 44
 private val TEST_SERVICE_1 = NsdServiceInfo().apply {
     serviceType = "_testservice._tcp"
     serviceName = "MyTestService"
@@ -78,6 +81,13 @@
     port = 12345
 }
 
+private val TEST_SERVICE_1_CUSTOM_HOST = NsdServiceInfo().apply {
+    serviceType = "_testservice._tcp"
+    serviceName = "MyTestService"
+    hostname = "MyTestHost"
+    port = 12345
+}
+
 @RunWith(DevSdkIgnoreRunner::class)
 @IgnoreUpTo(Build.VERSION_CODES.S_V2)
 class MdnsInterfaceAdvertiserTest {
@@ -183,6 +193,63 @@
     }
 
     @Test
+    fun testAddRemoveServiceWithCustomHost_restartProbingForProbingServices() {
+        val customHost1 = NsdServiceInfo().apply {
+            hostname = "MyTestHost"
+            hostAddresses = listOf(
+                    parseNumericAddress("192.0.2.23"),
+                    parseNumericAddress("2001:db8::1"))
+        }
+        addServiceAndFinishProbing(TEST_SERVICE_ID_1, customHost1)
+        addServiceAndFinishProbing(TEST_SERVICE_ID_2, TEST_SERVICE_1_CUSTOM_HOST)
+        repository.setServiceProbing(TEST_SERVICE_ID_2)
+        val probingInfo = mock(ProbingInfo::class.java)
+        doReturn("MyTestHost")
+                .`when`(repository).getHostnameForServiceId(TEST_SERVICE_ID_1)
+        doReturn(TEST_SERVICE_ID_2).`when`(probingInfo).serviceId
+        doReturn(listOf(probingInfo))
+                .`when`(repository).restartProbingForHostname("MyTestHost")
+        val inOrder = inOrder(prober, announcer)
+
+        // Remove the custom host: the custom host's announcement is stopped and the probing
+        // services which use that hostname are re-announced.
+        advertiser.removeService(TEST_SERVICE_ID_1)
+
+        inOrder.verify(prober).stop(TEST_SERVICE_ID_1)
+        inOrder.verify(announcer).stop(TEST_SERVICE_ID_1)
+        inOrder.verify(prober).stop(TEST_SERVICE_ID_2)
+        inOrder.verify(prober).startProbing(probingInfo)
+    }
+
+    @Test
+    fun testAddRemoveServiceWithCustomHost_restartAnnouncingForProbedServices() {
+        val customHost1 = NsdServiceInfo().apply {
+            hostname = "MyTestHost"
+            hostAddresses = listOf(
+                    parseNumericAddress("192.0.2.23"),
+                    parseNumericAddress("2001:db8::1"))
+        }
+        addServiceAndFinishProbing(TEST_SERVICE_ID_1, customHost1)
+        val announcementInfo =
+                addServiceAndFinishProbing(TEST_SERVICE_ID_2, TEST_SERVICE_1_CUSTOM_HOST)
+        doReturn("MyTestHost")
+                .`when`(repository).getHostnameForServiceId(TEST_SERVICE_ID_1)
+        doReturn(TEST_SERVICE_ID_2).`when`(announcementInfo).serviceId
+        doReturn(listOf(announcementInfo))
+                .`when`(repository).restartAnnouncingForHostname("MyTestHost")
+        clearInvocations(announcer)
+
+        // Remove the custom host: the custom host's announcement is stopped and the probed services
+        // which use that hostname are re-announced.
+        advertiser.removeService(TEST_SERVICE_ID_1)
+
+        verify(prober).stop(TEST_SERVICE_ID_1)
+        verify(announcer, atLeastOnce()).stop(TEST_SERVICE_ID_1)
+        verify(announcer).stop(TEST_SERVICE_ID_2)
+        verify(announcer).startSending(TEST_SERVICE_ID_2, announcementInfo, 0L /* initialDelayMs */)
+    }
+
+    @Test
     fun testDoubleRemove() {
         addServiceAndFinishProbing(TEST_SERVICE_ID_1, TEST_SERVICE_1)
 
diff --git a/tests/unit/java/com/android/server/connectivity/mdns/MdnsRecordRepositoryTest.kt b/tests/unit/java/com/android/server/connectivity/mdns/MdnsRecordRepositoryTest.kt
index c69b1e1..271cc65 100644
--- a/tests/unit/java/com/android/server/connectivity/mdns/MdnsRecordRepositoryTest.kt
+++ b/tests/unit/java/com/android/server/connectivity/mdns/MdnsRecordRepositoryTest.kt
@@ -24,6 +24,7 @@
 import com.android.server.connectivity.mdns.MdnsAnnouncer.AnnouncementInfo
 import com.android.server.connectivity.mdns.MdnsInterfaceAdvertiser.CONFLICT_HOST
 import com.android.server.connectivity.mdns.MdnsInterfaceAdvertiser.CONFLICT_SERVICE
+import com.android.server.connectivity.mdns.MdnsProber.ProbingInfo
 import com.android.server.connectivity.mdns.MdnsRecord.TYPE_A
 import com.android.server.connectivity.mdns.MdnsRecord.TYPE_AAAA
 import com.android.server.connectivity.mdns.MdnsRecord.TYPE_PTR
@@ -51,6 +52,10 @@
 import org.junit.Before
 import org.junit.Test
 import org.junit.runner.RunWith
+import org.mockito.ArgumentCaptor
+import org.mockito.ArgumentMatchers.eq
+import org.mockito.Mockito.mock
+import org.mockito.Mockito.verify
 
 private const val TEST_SERVICE_ID_1 = 42
 private const val TEST_SERVICE_ID_2 = 43
@@ -112,6 +117,14 @@
     port = TEST_PORT
 }
 
+private val TEST_SERVICE_CUSTOM_HOST_NO_ADDRESSES = NsdServiceInfo().apply {
+    hostname = "TestHost"
+    hostAddresses = listOf()
+    serviceType = "_testservice._tcp"
+    serviceName = "TestService"
+    port = TEST_PORT
+}
+
 @RunWith(DevSdkIgnoreRunner::class)
 @DevSdkIgnoreRule.IgnoreUpTo(Build.VERSION_CODES.S_V2)
 class MdnsRecordRepositoryTest {
@@ -1676,6 +1689,127 @@
         assertEquals(0, reply.additionalAnswers.size)
         assertEquals(knownAnswers, reply.knownAnswers)
     }
+
+    @Test
+    fun testRestartProbingForHostname() {
+        val repository = MdnsRecordRepository(thread.looper, deps, TEST_HOSTNAME, makeFlags())
+        repository.initWithService(TEST_CUSTOM_HOST_ID_1, TEST_CUSTOM_HOST_1,
+                setOf(TEST_SUBTYPE, TEST_SUBTYPE2))
+        repository.addService(TEST_SERVICE_CUSTOM_HOST_ID_1,
+                TEST_SERVICE_CUSTOM_HOST_NO_ADDRESSES, null)
+        repository.setServiceProbing(TEST_SERVICE_CUSTOM_HOST_ID_1)
+        repository.removeService(TEST_CUSTOM_HOST_ID_1)
+
+        val probingInfos = repository.restartProbingForHostname("TestHost")
+
+        assertEquals(1, probingInfos.size)
+        val probingInfo = probingInfos.get(0)
+        assertEquals(TEST_SERVICE_CUSTOM_HOST_ID_1, probingInfo.serviceId)
+        val packet = probingInfo.getPacket(0)
+        assertEquals(0, packet.transactionId)
+        assertEquals(MdnsConstants.FLAGS_QUERY, packet.flags)
+        assertEquals(0, packet.answers.size)
+        assertEquals(0, packet.additionalRecords.size)
+        assertEquals(1, packet.questions.size)
+        val serviceName = arrayOf("TestService", "_testservice", "_tcp", "local")
+        assertEquals(MdnsAnyRecord(serviceName, false /* unicast */), packet.questions[0])
+        assertThat(packet.authorityRecords).containsExactly(
+                MdnsServiceRecord(
+                        serviceName,
+                        0L /* receiptTimeMillis */,
+                        false /* cacheFlush */,
+                        SHORT_TTL /* ttlMillis */,
+                        0 /* servicePriority */,
+                        0 /* serviceWeight */,
+                        TEST_PORT,
+                        TEST_CUSTOM_HOST_1_NAME))
+    }
+
+    @Test
+    fun testRestartAnnouncingForHostname() {
+        val repository = MdnsRecordRepository(thread.looper, deps, TEST_HOSTNAME, makeFlags())
+        repository.initWithService(TEST_CUSTOM_HOST_ID_1, TEST_CUSTOM_HOST_1,
+                setOf(TEST_SUBTYPE, TEST_SUBTYPE2))
+        repository.addServiceAndFinishProbing(TEST_SERVICE_CUSTOM_HOST_ID_1,
+                TEST_SERVICE_CUSTOM_HOST_NO_ADDRESSES)
+        repository.removeService(TEST_CUSTOM_HOST_ID_1)
+
+        val announcementInfos = repository.restartAnnouncingForHostname("TestHost")
+
+        assertEquals(1, announcementInfos.size)
+        val announcementInfo = announcementInfos.get(0)
+        assertEquals(TEST_SERVICE_CUSTOM_HOST_ID_1, announcementInfo.serviceId)
+        val packet = announcementInfo.getPacket(0)
+        assertEquals(0, packet.transactionId)
+        assertEquals(0x8400 /* response, authoritative */, packet.flags)
+        assertEquals(0, packet.questions.size)
+        assertEquals(0, packet.authorityRecords.size)
+        val serviceName = arrayOf("TestService", "_testservice", "_tcp", "local")
+        val serviceType = arrayOf("_testservice", "_tcp", "local")
+        val v4AddrRev = getReverseDnsAddress(TEST_ADDRESSES[0].address)
+        val v6Addr1Rev = getReverseDnsAddress(TEST_ADDRESSES[1].address)
+        val v6Addr2Rev = getReverseDnsAddress(TEST_ADDRESSES[2].address)
+        assertThat(packet.answers).containsExactly(
+                MdnsPointerRecord(
+                        serviceType,
+                        0L /* receiptTimeMillis */,
+                        // Not a unique name owned by the announcer, so cacheFlush=false
+                        false /* cacheFlush */,
+                        4500000L /* ttlMillis */,
+                        serviceName),
+                MdnsServiceRecord(
+                        serviceName,
+                        0L /* receiptTimeMillis */,
+                        true /* cacheFlush */,
+                        120000L /* ttlMillis */,
+                        0 /* servicePriority */,
+                        0 /* serviceWeight */,
+                        TEST_PORT /* servicePort */,
+                        TEST_CUSTOM_HOST_1_NAME),
+                MdnsTextRecord(
+                        serviceName,
+                        0L /* receiptTimeMillis */,
+                        true /* cacheFlush */,
+                        4500000L /* ttlMillis */,
+                        emptyList() /* entries */),
+                MdnsPointerRecord(
+                        arrayOf("_services", "_dns-sd", "_udp", "local"),
+                        0L /* receiptTimeMillis */,
+                        false /* cacheFlush */,
+                        4500000L /* ttlMillis */,
+                        serviceType))
+        assertThat(packet.additionalRecords).containsExactly(
+                MdnsNsecRecord(v4AddrRev,
+                        0L /* receiptTimeMillis */,
+                        true /* cacheFlush */,
+                        120000L /* ttlMillis */,
+                        v4AddrRev,
+                        intArrayOf(TYPE_PTR)),
+                MdnsNsecRecord(TEST_HOSTNAME,
+                        0L /* receiptTimeMillis */,
+                        true /* cacheFlush */,
+                        120000L /* ttlMillis */,
+                        TEST_HOSTNAME,
+                        intArrayOf(TYPE_A, TYPE_AAAA)),
+                MdnsNsecRecord(v6Addr1Rev,
+                        0L /* receiptTimeMillis */,
+                        true /* cacheFlush */,
+                        120000L /* ttlMillis */,
+                        v6Addr1Rev,
+                        intArrayOf(TYPE_PTR)),
+                MdnsNsecRecord(v6Addr2Rev,
+                        0L /* receiptTimeMillis */,
+                        true /* cacheFlush */,
+                        120000L /* ttlMillis */,
+                        v6Addr2Rev,
+                        intArrayOf(TYPE_PTR)),
+                MdnsNsecRecord(serviceName,
+                        0L /* receiptTimeMillis */,
+                        true /* cacheFlush */,
+                        4500000L /* ttlMillis */,
+                        serviceName,
+                        intArrayOf(TYPE_TXT, TYPE_SRV)))
+    }
 }
 
 private fun MdnsRecordRepository.initWithService(