[mdns] add service-side impl for NSD service TTL support

This is the service-side implementation of the custom service TTL
support added in aosp/2606573.

Bug: 284903641
Test: atest CtsNetTestCases FrameworksNetTests
Change-Id: I35246dae37b9fd1710b99cdda10068928e418457
diff --git a/service-t/src/com/android/server/NsdService.java b/service-t/src/com/android/server/NsdService.java
index 9ba49d2..e8f48a3 100644
--- a/service-t/src/com/android/server/NsdService.java
+++ b/service-t/src/com/android/server/NsdService.java
@@ -28,6 +28,7 @@
 import static android.net.nsd.NsdManager.RESOLVE_SERVICE_SUCCEEDED;
 import static android.net.nsd.NsdManager.SUBTYPE_LABEL_REGEX;
 import static android.net.nsd.NsdManager.TYPE_REGEX;
+import static android.os.Process.SYSTEM_UID;
 import static android.provider.DeviceConfig.NAMESPACE_TETHERING;
 
 import static com.android.modules.utils.build.SdkLevel.isAtLeastU;
@@ -115,6 +116,7 @@
 import java.net.NetworkInterface;
 import java.net.SocketException;
 import java.net.UnknownHostException;
+import java.time.Duration;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
@@ -738,6 +740,33 @@
                 return new ArraySet<>(subtypeMap.values());
             }
 
+            private boolean checkTtl(
+                        @Nullable Duration ttl, @NonNull ClientInfo clientInfo) {
+                if (ttl == null) {
+                    return true;
+                }
+
+                final long ttlSeconds = ttl.toSeconds();
+                final int uid = clientInfo.getUid();
+
+                // Allows Thread module in the system_server to register TTL that is smaller than
+                // 30 seconds
+                final long minTtlSeconds = uid == SYSTEM_UID ? 0 : NsdManager.TTL_SECONDS_MIN;
+
+                // Allows Thread module in the system_server to register TTL that is larger than
+                // 10 hours
+                final long maxTtlSeconds =
+                        uid == SYSTEM_UID ? 0xffffffffL : NsdManager.TTL_SECONDS_MAX;
+
+                if (ttlSeconds < minTtlSeconds || ttlSeconds > maxTtlSeconds) {
+                    mServiceLogs.e("ttlSeconds exceeds allowed range (value = "
+                            + ttlSeconds + ", allowedRange = [" + minTtlSeconds
+                            + ", " + maxTtlSeconds + " ])");
+                    return false;
+                }
+                return true;
+            }
+
             @Override
             public boolean processMessage(Message msg) {
                 final ClientInfo clientInfo;
@@ -964,11 +993,19 @@
                                 break;
                             }
 
+                            if (!checkTtl(advertisingRequest.getTtl(), clientInfo)) {
+                                clientInfo.onRegisterServiceFailedImmediately(clientRequestId,
+                                        NsdManager.FAILURE_BAD_PARAMETERS, false /* isLegacy */);
+                                break;
+                            }
+
                             serviceInfo.setSubtypes(subtypes);
                             maybeStartMonitoringSockets();
                             final MdnsAdvertisingOptions mdnsAdvertisingOptions =
-                                    MdnsAdvertisingOptions.newBuilder().setIsOnlyUpdate(
-                                            isUpdateOnly).build();
+                                    MdnsAdvertisingOptions.newBuilder()
+                                            .setIsOnlyUpdate(isUpdateOnly)
+                                            .setTtl(advertisingRequest.getTtl())
+                                            .build();
                             mAdvertiser.addOrUpdateService(transactionId, serviceInfo,
                                     mdnsAdvertisingOptions, clientInfo.mUid);
                             storeAdvertiserRequestMap(clientRequestId, transactionId, clientInfo,
@@ -1511,6 +1548,7 @@
                         network == null ? INetd.LOCAL_NET_ID : network.netId,
                         serviceInfo.getInterfaceIndex());
                 servInfo.setSubtypes(dedupSubtypeLabels(serviceInfo.getSubtypes()));
+                servInfo.setExpirationTime(serviceInfo.getExpirationTime());
                 return servInfo;
             }
 
@@ -2671,6 +2709,10 @@
             return sb.toString();
         }
 
+        public int getUid() {
+            return mUid;
+        }
+
         private boolean isPreSClient() {
             return mIsPreSClient;
         }
diff --git a/service-t/src/com/android/server/connectivity/mdns/MdnsAdvertiser.java b/service-t/src/com/android/server/connectivity/mdns/MdnsAdvertiser.java
index 0b60572..c162bcc 100644
--- a/service-t/src/com/android/server/connectivity/mdns/MdnsAdvertiser.java
+++ b/service-t/src/com/android/server/connectivity/mdns/MdnsAdvertiser.java
@@ -449,7 +449,8 @@
             mPendingRegistrations.put(id, registration);
             for (int i = 0; i < mAdvertisers.size(); i++) {
                 try {
-                    mAdvertisers.valueAt(i).addService(id, registration.getServiceInfo());
+                    mAdvertisers.valueAt(i).addService(id, registration.getServiceInfo(),
+                            registration.getAdvertisingOptions());
                 } catch (NameConflictException e) {
                     mSharedLog.wtf("Name conflict adding services that should have unique names",
                             e);
@@ -515,7 +516,7 @@
                 final Registration registration = mPendingRegistrations.valueAt(i);
                 try {
                     advertiser.addService(mPendingRegistrations.keyAt(i),
-                            registration.getServiceInfo());
+                            registration.getServiceInfo(), registration.getAdvertisingOptions());
                 } catch (NameConflictException e) {
                     mSharedLog.wtf("Name conflict adding services that should have unique names",
                             e);
@@ -587,15 +588,17 @@
         @NonNull
         private NsdServiceInfo mServiceInfo;
         final int mClientUid;
+        private final MdnsAdvertisingOptions mAdvertisingOptions;
         int mConflictDuringProbingCount;
         int mConflictAfterProbingCount;
 
-
-        private Registration(@NonNull NsdServiceInfo serviceInfo, int clientUid) {
+        private Registration(@NonNull NsdServiceInfo serviceInfo, int clientUid,
+                @NonNull MdnsAdvertisingOptions advertisingOptions) {
             this.mOriginalServiceName = serviceInfo.getServiceName();
             this.mOriginalHostname = serviceInfo.getHostname();
             this.mServiceInfo = serviceInfo;
             this.mClientUid = clientUid;
+            this.mAdvertisingOptions = advertisingOptions;
         }
 
         /** Check if the new {@link NsdServiceInfo} doesn't update any data other than subtypes. */
@@ -697,6 +700,11 @@
         public NsdServiceInfo getServiceInfo() {
             return mServiceInfo;
         }
+
+        @NonNull
+        public MdnsAdvertisingOptions getAdvertisingOptions() {
+            return mAdvertisingOptions;
+        }
     }
 
     /**
@@ -855,7 +863,7 @@
             }
             mSharedLog.i("Adding service " + service + " with ID " + id + " and subtypes "
                     + subtypes + " advertisingOptions " + advertisingOptions);
-            registration = new Registration(service, clientUid);
+            registration = new Registration(service, clientUid, advertisingOptions);
             final BiPredicate<Network, InterfaceAdvertiserRequest> checkConflictFilter;
             if (network == null) {
                 // If registering on all networks, no advertiser must have conflicts
diff --git a/service-t/src/com/android/server/connectivity/mdns/MdnsAdvertisingOptions.java b/service-t/src/com/android/server/connectivity/mdns/MdnsAdvertisingOptions.java
index e7a6ca7..a81d1e4 100644
--- a/service-t/src/com/android/server/connectivity/mdns/MdnsAdvertisingOptions.java
+++ b/service-t/src/com/android/server/connectivity/mdns/MdnsAdvertisingOptions.java
@@ -16,6 +16,11 @@
 
 package com.android.server.connectivity.mdns;
 
+import android.annotation.Nullable;
+
+import java.time.Duration;
+import java.util.Objects;
+
 /**
  * API configuration parameters for advertising the mDNS service.
  *
@@ -27,13 +32,15 @@
 
     private static MdnsAdvertisingOptions sDefaultOptions;
     private final boolean mIsOnlyUpdate;
+    @Nullable
+    private final Duration mTtl;
 
     /**
      * Parcelable constructs for a {@link MdnsAdvertisingOptions}.
      */
-    MdnsAdvertisingOptions(
-            boolean isOnlyUpdate) {
+    MdnsAdvertisingOptions(boolean isOnlyUpdate, @Nullable Duration ttl) {
         this.mIsOnlyUpdate = isOnlyUpdate;
+        this.mTtl = ttl;
     }
 
     /**
@@ -60,9 +67,36 @@
         return mIsOnlyUpdate;
     }
 
+    /**
+     * Returns the TTL for all records in a service.
+     */
+    @Nullable
+    public Duration getTtl() {
+        return mTtl;
+    }
+
+    @Override
+    public boolean equals(Object other) {
+        if (this == other) {
+            return true;
+        } else if (!(other instanceof MdnsAdvertisingOptions)) {
+            return false;
+        } else {
+            final MdnsAdvertisingOptions otherOptions = (MdnsAdvertisingOptions) other;
+            return mIsOnlyUpdate == otherOptions.mIsOnlyUpdate
+                    && Objects.equals(mTtl, otherOptions.mTtl);
+        }
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(mIsOnlyUpdate, mTtl);
+    }
+
     @Override
     public String toString() {
-        return "MdnsAdvertisingOptions{" + "mIsOnlyUpdate=" + mIsOnlyUpdate + '}';
+        return "MdnsAdvertisingOptions{" + "mIsOnlyUpdate=" + mIsOnlyUpdate + ", mTtl=" + mTtl
+                + '}';
     }
 
     /**
@@ -70,6 +104,8 @@
      */
     public static final class Builder {
         private boolean mIsOnlyUpdate = false;
+        @Nullable
+        private Duration mTtl;
 
         private Builder() {
         }
@@ -83,10 +119,18 @@
         }
 
         /**
+         * Sets the TTL duration for all records of the service.
+         */
+        public Builder setTtl(@Nullable Duration ttl) {
+            this.mTtl = ttl;
+            return this;
+        }
+
+        /**
          * Builds a {@link MdnsAdvertisingOptions} with the arguments supplied to this builder.
          */
         public MdnsAdvertisingOptions build() {
-            return new MdnsAdvertisingOptions(mIsOnlyUpdate);
+            return new MdnsAdvertisingOptions(mIsOnlyUpdate, mTtl);
         }
     }
 }
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 aa51c41..c2363c0 100644
--- a/service-t/src/com/android/server/connectivity/mdns/MdnsInterfaceAdvertiser.java
+++ b/service-t/src/com/android/server/connectivity/mdns/MdnsInterfaceAdvertiser.java
@@ -258,8 +258,10 @@
      *
      * @throws NameConflictException There is already a service being advertised with that name.
      */
-    public void addService(int id, NsdServiceInfo service) throws NameConflictException {
-        final int replacedExitingService = mRecordRepository.addService(id, service);
+    public void addService(int id, NsdServiceInfo service,
+            @NonNull MdnsAdvertisingOptions advertisingOptions) throws NameConflictException {
+        final int replacedExitingService =
+                mRecordRepository.addService(id, service, advertisingOptions.getTtl());
         // Cancel announcements for the existing service. This only happens for exiting services
         // (so cancelling exiting announcements), as per RecordRepository.addService.
         if (replacedExitingService >= 0) {
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 ed0bde2..ac64c3a 100644
--- a/service-t/src/com/android/server/connectivity/mdns/MdnsRecordRepository.java
+++ b/service-t/src/com/android/server/connectivity/mdns/MdnsRecordRepository.java
@@ -45,6 +45,7 @@
 import java.net.InetAddress;
 import java.net.InetSocketAddress;
 import java.net.NetworkInterface;
+import java.time.Duration;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
@@ -75,9 +76,9 @@
     // TTL for records with a host name as the resource record's name (e.g., A, AAAA, HINFO) or a
     // host name contained within the resource record's rdata (e.g., SRV, reverse mapping PTR
     // record)
-    private static final long NAME_RECORDS_TTL_MILLIS = TimeUnit.SECONDS.toMillis(120);
+    private static final long DEFAULT_NAME_RECORDS_TTL_MILLIS = TimeUnit.SECONDS.toMillis(120);
     // TTL for other records
-    private static final long NON_NAME_RECORDS_TTL_MILLIS = TimeUnit.MINUTES.toMillis(75);
+    private static final long DEFAULT_NON_NAME_RECORDS_TTL_MILLIS = TimeUnit.MINUTES.toMillis(75);
 
     // Top-level domain for link-local queries, as per RFC6762 3.
     private static final String LOCAL_TLD = "local";
@@ -193,6 +194,9 @@
          */
         private boolean isProbing;
 
+        @Nullable
+        private Duration ttl;
+
         /**
          * Create a ServiceRegistration with only update the subType.
          */
@@ -200,16 +204,32 @@
             NsdServiceInfo newServiceInfo = new NsdServiceInfo(serviceInfo);
             newServiceInfo.setSubtypes(newSubtypes);
             return new ServiceRegistration(srvRecord.record.getServiceHost(), newServiceInfo,
-                    repliedServiceCount, sentPacketCount, exiting, isProbing);
+                    repliedServiceCount, sentPacketCount, exiting, isProbing, ttl);
         }
 
         /**
          * Create a ServiceRegistration for dns-sd service registration (RFC6763).
          */
         ServiceRegistration(@NonNull String[] deviceHostname, @NonNull NsdServiceInfo serviceInfo,
-                int repliedServiceCount, int sentPacketCount, boolean exiting, boolean isProbing) {
+                int repliedServiceCount, int sentPacketCount, boolean exiting, boolean isProbing,
+                @Nullable Duration ttl) {
             this.serviceInfo = serviceInfo;
 
+            final long nonNameRecordsTtlMillis;
+            final long nameRecordsTtlMillis;
+
+            // When custom TTL is specified, all records of the service will use the custom TTL.
+            // This is typically useful for SRP (Service Registration Protocol:
+            // https://datatracker.ietf.org/doc/html/draft-ietf-dnssd-srp-24) Advertising Proxy
+            // where all records in a single SRP are required the same TTL.
+            if (ttl != null) {
+                nonNameRecordsTtlMillis = ttl.toMillis();
+                nameRecordsTtlMillis = ttl.toMillis();
+            } else {
+                nonNameRecordsTtlMillis = DEFAULT_NON_NAME_RECORDS_TTL_MILLIS;
+                nameRecordsTtlMillis = DEFAULT_NAME_RECORDS_TTL_MILLIS;
+            }
+
             final boolean hasService = !TextUtils.isEmpty(serviceInfo.getServiceType());
             final boolean hasCustomHost = !TextUtils.isEmpty(serviceInfo.getHostname());
             final String[] hostname =
@@ -229,7 +249,7 @@
                                 serviceType,
                                 0L /* receiptTimeMillis */,
                                 false /* cacheFlush */,
-                                NON_NAME_RECORDS_TTL_MILLIS,
+                                nonNameRecordsTtlMillis,
                                 serviceName),
                         true /* sharedName */));
                 for (String subtype : serviceInfo.getSubtypes()) {
@@ -239,7 +259,7 @@
                                     MdnsUtils.constructFullSubtype(serviceType, subtype),
                                     0L /* receiptTimeMillis */,
                                     false /* cacheFlush */,
-                                    NON_NAME_RECORDS_TTL_MILLIS,
+                                    nonNameRecordsTtlMillis,
                                     serviceName),
                             true /* sharedName */));
                 }
@@ -249,7 +269,7 @@
                         new MdnsServiceRecord(serviceName,
                                 0L /* receiptTimeMillis */,
                                 true /* cacheFlush */,
-                                NAME_RECORDS_TTL_MILLIS,
+                                nameRecordsTtlMillis,
                                 0 /* servicePriority */, 0 /* serviceWeight */,
                                 serviceInfo.getPort(),
                                 hostname),
@@ -261,7 +281,7 @@
                                 0L /* receiptTimeMillis */,
                                 // Service name is verified unique after probing
                                 true /* cacheFlush */,
-                                NON_NAME_RECORDS_TTL_MILLIS,
+                                nonNameRecordsTtlMillis,
                                 attrsToTextEntries(serviceInfo.getAttributes())),
                         false /* sharedName */);
 
@@ -275,7 +295,7 @@
                                 DNS_SD_SERVICE_TYPE,
                                 0L /* receiptTimeMillis */,
                                 false /* cacheFlush */,
-                                NON_NAME_RECORDS_TTL_MILLIS,
+                                nonNameRecordsTtlMillis,
                                 serviceType),
                         true /* sharedName */));
             } else {
@@ -292,7 +312,7 @@
                                     new MdnsInetAddressRecord(hostname,
                                             0L /* receiptTimeMillis */,
                                             true /* cacheFlush */,
-                                            NAME_RECORDS_TTL_MILLIS,
+                                            nameRecordsTtlMillis,
                                             address),
                                     false /* sharedName */));
                 }
@@ -315,9 +335,9 @@
          * @param serviceInfo Service to advertise
          */
         ServiceRegistration(@NonNull String[] deviceHostname, @NonNull NsdServiceInfo serviceInfo,
-                int repliedServiceCount, int sentPacketCount) {
+                int repliedServiceCount, int sentPacketCount, @Nullable Duration ttl) {
             this(deviceHostname, serviceInfo,repliedServiceCount, sentPacketCount,
-                    false /* exiting */, true /* isProbing */);
+                    false /* exiting */, true /* isProbing */, ttl);
         }
 
         void setProbing(boolean probing) {
@@ -339,7 +359,7 @@
                             revDnsAddr,
                             0L /* receiptTimeMillis */,
                             true /* cacheFlush */,
-                            NAME_RECORDS_TTL_MILLIS,
+                            DEFAULT_NAME_RECORDS_TTL_MILLIS,
                             mDeviceHostname),
                     false /* sharedName */));
 
@@ -349,7 +369,7 @@
                             mDeviceHostname,
                             0L /* receiptTimeMillis */,
                             true /* cacheFlush */,
-                            NAME_RECORDS_TTL_MILLIS,
+                            DEFAULT_NAME_RECORDS_TTL_MILLIS,
                             addr.getAddress()),
                     false /* sharedName */));
         }
@@ -378,11 +398,13 @@
      * This may remove/replace any existing service that used the name added but is exiting.
      * @param serviceId A unique service ID.
      * @param serviceInfo Service info to add.
+     * @param ttl the TTL duration for all records of {@code serviceInfo} or {@code null}
      * @return If the added service replaced another with a matching name (which was exiting), the
      *         ID of the replaced service.
      * @throws NameConflictException There is already a (non-exiting) service using the name.
      */
-    public int addService(int serviceId, NsdServiceInfo serviceInfo) throws NameConflictException {
+    public int addService(int serviceId, NsdServiceInfo serviceInfo, @Nullable Duration ttl)
+            throws NameConflictException {
         if (mServices.contains(serviceId)) {
             throw new IllegalArgumentException(
                     "Service ID must not be reused across registrations: " + serviceId);
@@ -397,7 +419,7 @@
 
         final ServiceRegistration registration = new ServiceRegistration(
                 mDeviceHostname, serviceInfo, NO_PACKET /* repliedServiceCount */,
-                NO_PACKET /* sentPacketCount */);
+                NO_PACKET /* sentPacketCount */, ttl);
         mServices.put(serviceId, registration);
 
         // Remove existing exiting service
@@ -776,7 +798,7 @@
                     true /* cacheFlush */,
                     // TODO: RFC6762 6.1: "In general, the TTL given for an NSEC record SHOULD
                     // be the same as the TTL that the record would have had, had it existed."
-                    NAME_RECORDS_TTL_MILLIS,
+                    DEFAULT_NAME_RECORDS_TTL_MILLIS,
                     question.getName(),
                     new int[] { question.getType() });
             additionalAnswerInfo.add(
@@ -1211,7 +1233,7 @@
         if (existing == null) return null;
 
         final ServiceRegistration newService = new ServiceRegistration(mDeviceHostname, newInfo,
-                existing.repliedServiceCount, existing.sentPacketCount);
+                existing.repliedServiceCount, existing.sentPacketCount, existing.ttl);
         mServices.put(serviceId, newService);
         return makeProbingInfo(serviceId, newService);
     }
diff --git a/service-t/src/com/android/server/connectivity/mdns/MdnsServiceInfo.java b/service-t/src/com/android/server/connectivity/mdns/MdnsServiceInfo.java
index 78df6df..f60a95e 100644
--- a/service-t/src/com/android/server/connectivity/mdns/MdnsServiceInfo.java
+++ b/service-t/src/com/android/server/connectivity/mdns/MdnsServiceInfo.java
@@ -28,6 +28,7 @@
 import com.android.net.module.util.ByteUtils;
 
 import java.nio.charset.Charset;
+import java.time.Instant;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
@@ -62,7 +63,8 @@
                             source.createStringArrayList(),
                             source.createTypedArrayList(TextEntry.CREATOR),
                             source.readInt(),
-                            source.readParcelable(null));
+                            source.readParcelable(Network.class.getClassLoader()),
+                            Instant.ofEpochSecond(source.readLong()));
                 }
 
                 @Override
@@ -89,6 +91,9 @@
     @Nullable
     private final Network network;
 
+    @NonNull
+    private final Instant expirationTime;
+
     /** Constructs a {@link MdnsServiceInfo} object with default values. */
     public MdnsServiceInfo(
             String serviceInstanceName,
@@ -110,7 +115,8 @@
                 textStrings,
                 /* textEntries= */ null,
                 /* interfaceIndex= */ INTERFACE_INDEX_UNSPECIFIED,
-                /* network= */ null);
+                /* network= */ null,
+                /* expirationTime= */ Instant.MAX);
     }
 
     /** Constructs a {@link MdnsServiceInfo} object with default values. */
@@ -135,7 +141,8 @@
                 textStrings,
                 textEntries,
                 /* interfaceIndex= */ INTERFACE_INDEX_UNSPECIFIED,
-                /* network= */ null);
+                /* network= */ null,
+                /* expirationTime= */ Instant.MAX);
     }
 
     /**
@@ -165,7 +172,8 @@
                 textStrings,
                 textEntries,
                 interfaceIndex,
-                /* network= */ null);
+                /* network= */ null,
+                /* expirationTime= */ Instant.MAX);
     }
 
     /**
@@ -184,7 +192,8 @@
             @Nullable List<String> textStrings,
             @Nullable List<TextEntry> textEntries,
             int interfaceIndex,
-            @Nullable Network network) {
+            @Nullable Network network,
+            @NonNull Instant expirationTime) {
         this.serviceInstanceName = serviceInstanceName;
         this.serviceType = serviceType;
         this.subtypes = new ArrayList<>();
@@ -217,6 +226,7 @@
         this.attributes = Collections.unmodifiableMap(attributes);
         this.interfaceIndex = interfaceIndex;
         this.network = network;
+        this.expirationTime = Instant.ofEpochSecond(expirationTime.getEpochSecond());
     }
 
     private static List<TextEntry> parseTextStrings(List<String> textStrings) {
@@ -314,6 +324,17 @@
     }
 
     /**
+     * Returns the timestamp after when this service is expired or {@code null} if the expiration
+     * time is unknown.
+     *
+     * A service is considered expired if any of its DNS record is expired.
+     */
+    @NonNull
+    public Instant getExpirationTime() {
+        return expirationTime;
+    }
+
+    /**
      * Returns attribute value for {@code key} as a UTF-8 string. It's the caller who must make sure
      * that the value of {@code key} is indeed a UTF-8 string. {@code null} will be returned if no
      * attribute value exists for {@code key}.
@@ -364,6 +385,7 @@
         out.writeTypedList(textEntries);
         out.writeInt(interfaceIndex);
         out.writeParcelable(network, 0);
+        out.writeLong(expirationTime.getEpochSecond());
     }
 
     @Override
@@ -377,7 +399,8 @@
                 + ", interfaceIndex: " + interfaceIndex
                 + ", network: " + network
                 + ", textStrings: " + textStrings
-                + ", textEntries: " + textEntries;
+                + ", textEntries: " + textEntries
+                + ", expirationTime: " + expirationTime;
     }
 
 
@@ -496,4 +519,4 @@
             out.writeByteArray(value);
         }
     }
-}
\ No newline at end of file
+}
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 4cb88b4..16f6362 100644
--- a/service-t/src/com/android/server/connectivity/mdns/MdnsServiceTypeClient.java
+++ b/service-t/src/com/android/server/connectivity/mdns/MdnsServiceTypeClient.java
@@ -37,6 +37,7 @@
 
 import java.net.Inet4Address;
 import java.net.Inet6Address;
+import java.time.Instant;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
@@ -309,6 +310,7 @@
             textStrings = response.getTextRecord().getStrings();
             textEntries = response.getTextRecord().getEntries();
         }
+        Instant now = Instant.now();
         // TODO: Throw an error message if response doesn't have Inet6 or Inet4 address.
         return new MdnsServiceInfo(
                 serviceInstanceName,
@@ -321,7 +323,8 @@
                 textStrings,
                 textEntries,
                 response.getInterfaceIndex(),
-                response.getNetwork());
+                response.getNetwork(),
+                now.plusMillis(response.getMinRemainingTtl(now.toEpochMilli())));
     }
 
     /**