Merge "Select Thread channel from preferred or supported channel mask" into main
diff --git a/common/FlaggedApi.bp b/common/FlaggedApi.bp
index c382e76..449d7ae 100644
--- a/common/FlaggedApi.bp
+++ b/common/FlaggedApi.bp
@@ -21,3 +21,11 @@
     srcs: ["flags.aconfig"],
     visibility: ["//packages/modules/Connectivity:__subpackages__"],
 }
+
+aconfig_declarations {
+    name: "nearby_flags",
+    package: "com.android.nearby.flags",
+    container: "system",
+    srcs: ["nearby_flags.aconfig"],
+    visibility: ["//packages/modules/Connectivity:__subpackages__"],
+}
diff --git a/nearby/flags/nearby_flags.aconfig b/common/nearby_flags.aconfig
similarity index 100%
rename from nearby/flags/nearby_flags.aconfig
rename to common/nearby_flags.aconfig
diff --git a/framework-t/Android.bp b/framework-t/Android.bp
index 9203a3e..e40b55c 100644
--- a/framework-t/Android.bp
+++ b/framework-t/Android.bp
@@ -197,6 +197,7 @@
     ],
     aconfig_declarations: [
         "com.android.net.flags-aconfig",
+        "nearby_flags",
     ],
 }
 
diff --git a/framework/src/android/net/ConnectivityManager.java b/framework/src/android/net/ConnectivityManager.java
index 1ea1815..915ec52 100644
--- a/framework/src/android/net/ConnectivityManager.java
+++ b/framework/src/android/net/ConnectivityManager.java
@@ -74,6 +74,7 @@
 import android.util.SparseIntArray;
 
 import com.android.internal.annotations.GuardedBy;
+import com.android.modules.utils.build.SdkLevel;
 
 import libcore.net.event.NetworkEventDispatcher;
 
@@ -6278,9 +6279,13 @@
     // Only the system server process and the network stack have access.
     @FlaggedApi(Flags.SUPPORT_IS_UID_NETWORKING_BLOCKED)
     @SystemApi(client = MODULE_LIBRARIES)
-    @RequiresApi(Build.VERSION_CODES.TIRAMISU)  // BPF maps were only mainlined in T
+    // Note b/326143935 kernel bug can trigger crash on some T device.
+    @RequiresApi(VERSION_CODES.UPSIDE_DOWN_CAKE)
     @RequiresPermission(NetworkStack.PERMISSION_MAINLINE_NETWORK_STACK)
     public boolean isUidNetworkingBlocked(int uid, boolean isNetworkMetered) {
+        if (!SdkLevel.isAtLeastU()) {
+            Log.wtf(TAG, "isUidNetworkingBlocked is not supported on pre-U devices");
+        }
         final BpfNetMapsReader reader = BpfNetMapsReader.getInstance();
         // Note that before V, the data saver status in bpf is written by ConnectivityService
         // when receiving {@link #ACTION_RESTRICT_BACKGROUND_CHANGED}. Thus,
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 fe9bbba..56202fd 100644
--- a/service-t/src/com/android/server/connectivity/mdns/MdnsFeatureFlags.java
+++ b/service-t/src/com/android/server/connectivity/mdns/MdnsFeatureFlags.java
@@ -118,6 +118,14 @@
     }
 
     /**
+     * Indicates whether {@link #NSD_KNOWN_ANSWER_SUPPRESSION} is enabled, including for testing.
+     */
+    public boolean isKnownAnswerSuppressionEnabled() {
+        return mIsKnownAnswerSuppressionEnabled
+                || isForceEnabledForTest(NSD_KNOWN_ANSWER_SUPPRESSION);
+    }
+
+    /**
      * The constructor for {@link MdnsFeatureFlags}.
      */
     public MdnsFeatureFlags(boolean isOffloadFeatureEnabled,
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 96a59e2..ed0bde2 100644
--- a/service-t/src/com/android/server/connectivity/mdns/MdnsRecordRepository.java
+++ b/service-t/src/com/android/server/connectivity/mdns/MdnsRecordRepository.java
@@ -538,7 +538,7 @@
     }
 
     private boolean isTruncatedKnownAnswerPacket(MdnsPacket packet) {
-        if (!mMdnsFeatureFlags.mIsKnownAnswerSuppressionEnabled
+        if (!mMdnsFeatureFlags.isKnownAnswerSuppressionEnabled()
                 // Should ignore the response packet.
                 || (packet.flags & MdnsConstants.FLAGS_RESPONSE) != 0) {
             return false;
@@ -745,7 +745,7 @@
             // RR TTL as known by the Multicast DNS responder, the responder MUST
             // send an answer so as to update the querier's cache before the record
             // becomes in danger of expiration.
-            if (mMdnsFeatureFlags.mIsKnownAnswerSuppressionEnabled
+            if (mMdnsFeatureFlags.isKnownAnswerSuppressionEnabled()
                     && isKnownAnswer(info.record, knownAnswerRecords)) {
                 continue;
             }
diff --git a/service-t/src/com/android/server/connectivity/mdns/MdnsReplySender.java b/service-t/src/com/android/server/connectivity/mdns/MdnsReplySender.java
index a46be3b..db3845a 100644
--- a/service-t/src/com/android/server/connectivity/mdns/MdnsReplySender.java
+++ b/service-t/src/com/android/server/connectivity/mdns/MdnsReplySender.java
@@ -145,7 +145,7 @@
     public void queueReply(@NonNull MdnsReplyInfo reply) {
         ensureRunningOnHandlerThread(mHandler);
 
-        if (mMdnsFeatureFlags.mIsKnownAnswerSuppressionEnabled) {
+        if (mMdnsFeatureFlags.isKnownAnswerSuppressionEnabled()) {
             mDependencies.removeMessages(mHandler, MSG_SEND, reply.source);
 
             final MdnsReplyInfo queuingReply = mSrcReplies.remove(reply.source);
@@ -231,7 +231,7 @@
         @Override
         public void handleMessage(@NonNull Message msg) {
             final MdnsReplyInfo replyInfo;
-            if (mMdnsFeatureFlags.mIsKnownAnswerSuppressionEnabled) {
+            if (mMdnsFeatureFlags.isKnownAnswerSuppressionEnabled()) {
                 // Retrieve the MdnsReplyInfo from the map via a source address, as the reply info
                 // will be combined or updated.
                 final InetSocketAddress source = (InetSocketAddress) msg.obj;
diff --git a/service-t/src/com/android/server/net/TrafficStatsRateLimitCache.java b/service-t/src/com/android/server/net/TrafficStatsRateLimitCache.java
new file mode 100644
index 0000000..8598ac4
--- /dev/null
+++ b/service-t/src/com/android/server/net/TrafficStatsRateLimitCache.java
@@ -0,0 +1,134 @@
+/*
+ * Copyright (C) 2024 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.server.net;
+
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+import android.net.NetworkStats;
+
+import com.android.internal.annotations.GuardedBy;
+
+import java.time.Clock;
+import java.util.HashMap;
+import java.util.Objects;
+
+/**
+ * A thread-safe cache for storing and retrieving {@link NetworkStats.Entry} objects,
+ * with an adjustable expiry duration to manage data freshness.
+ */
+class TrafficStatsRateLimitCache {
+    private final Clock mClock;
+    private final long mExpiryDurationMs;
+
+    /**
+     * Constructs a new {@link TrafficStatsRateLimitCache} with the specified expiry duration.
+     *
+     * @param clock The {@link Clock} to use for determining timestamps.
+     * @param expiryDurationMs The expiry duration in milliseconds.
+     */
+    TrafficStatsRateLimitCache(@NonNull Clock clock, long expiryDurationMs) {
+        mClock = clock;
+        mExpiryDurationMs = expiryDurationMs;
+    }
+
+    private static class TrafficStatsCacheKey {
+        @Nullable
+        public final String iface;
+        public final int uid;
+
+        TrafficStatsCacheKey(@Nullable String iface, int uid) {
+            this.iface = iface;
+            this.uid = uid;
+        }
+
+        @Override
+        public boolean equals(Object o) {
+            if (this == o) return true;
+            if (!(o instanceof TrafficStatsCacheKey)) return false;
+            TrafficStatsCacheKey that = (TrafficStatsCacheKey) o;
+            return uid == that.uid && Objects.equals(iface, that.iface);
+        }
+
+        @Override
+        public int hashCode() {
+            return Objects.hash(iface, uid);
+        }
+    }
+
+    private static class TrafficStatsCacheValue {
+        public final long timestamp;
+        @NonNull
+        public final NetworkStats.Entry entry;
+
+        TrafficStatsCacheValue(long timestamp, NetworkStats.Entry entry) {
+            this.timestamp = timestamp;
+            this.entry = entry;
+        }
+    }
+
+    @GuardedBy("mMap")
+    private final HashMap<TrafficStatsCacheKey, TrafficStatsCacheValue> mMap = new HashMap<>();
+
+    /**
+     * Retrieves a {@link NetworkStats.Entry} from the cache, associated with the given key.
+     *
+     * @param iface The interface name to include in the cache key. Null if not applicable.
+     * @param uid The UID to include in the cache key. {@code UID_ALL} if not applicable.
+     * @return The cached {@link NetworkStats.Entry}, or null if not found or expired.
+     */
+    @Nullable
+    NetworkStats.Entry get(String iface, int uid) {
+        final TrafficStatsCacheKey key = new TrafficStatsCacheKey(iface, uid);
+        synchronized (mMap) { // Synchronize for thread-safety
+            final TrafficStatsCacheValue value = mMap.get(key);
+            if (value != null && !isExpired(value.timestamp)) {
+                return value.entry;
+            } else {
+                mMap.remove(key); // Remove expired entries
+                return null;
+            }
+        }
+    }
+
+    /**
+     * Stores a {@link NetworkStats.Entry} in the cache, associated with the given key.
+     *
+     * @param iface The interface name to include in the cache key. Null if not applicable.
+     * @param uid   The UID to include in the cache key. {@code UID_ALL} if not applicable.
+     * @param entry The {@link NetworkStats.Entry} to store in the cache.
+     */
+    void put(String iface, int uid, @NonNull final NetworkStats.Entry entry) {
+        Objects.requireNonNull(entry);
+        final TrafficStatsCacheKey key = new TrafficStatsCacheKey(iface, uid);
+        synchronized (mMap) { // Synchronize for thread-safety
+            mMap.put(key, new TrafficStatsCacheValue(mClock.millis(), entry));
+        }
+    }
+
+    /**
+     * Clear the cache.
+     */
+    void clear() {
+        synchronized (mMap) {
+            mMap.clear();
+        }
+    }
+
+    private boolean isExpired(long timestamp) {
+        return mClock.millis() > timestamp + mExpiryDurationMs;
+    }
+}
diff --git a/tests/cts/net/src/android/net/cts/NsdManagerTest.kt b/tests/cts/net/src/android/net/cts/NsdManagerTest.kt
index 6db372f..ce2c2c1 100644
--- a/tests/cts/net/src/android/net/cts/NsdManagerTest.kt
+++ b/tests/cts/net/src/android/net/cts/NsdManagerTest.kt
@@ -1716,6 +1716,177 @@
         }
     }
 
+    @Test
+    fun testReplyWhenKnownAnswerSuppressionFlagSet() {
+        // 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_known_answer_suppression", "1")
+        deviceConfigRule.setConfig(NAMESPACE_TETHERING, "test_nsd_unicast_reply_enabled", "1")
+
+        val si = makeTestServiceInfo(testNetwork1.network)
+
+        // Register service on testNetwork1
+        val registrationRecord = NsdRegistrationRecord()
+        var nsResponder: NSResponder? = null
+        tryTest {
+            registerService(registrationRecord, si)
+            val packetReader = TapPacketReader(Handler(handlerThread.looper),
+                    testNetwork1.iface.fileDescriptor.fileDescriptor, 1500 /* maxPacketSize */)
+            packetReader.startAsyncForTest()
+
+            handlerThread.waitForIdle(TIMEOUT_MS)
+            /*
+            Send a query with a known answer. Expect to receive a response containing TXT record
+            only.
+            Generated with:
+            scapy.raw(scapy.DNS(rd=0, qr=0, aa=0, qd =
+                    scapy.DNSQR(qname='_nmt123456789._tcp.local', qtype='PTR',
+                            qclass=0x8001) /
+                    scapy.DNSQR(qname='NsdTest123456789._nmt123456789._tcp.local', qtype='TXT',
+                            qclass=0x8001),
+                    an = scapy.DNSRR(rrname='_nmt123456789._tcp.local', type='PTR', ttl=4500,
+                            rdata='NsdTest123456789._nmt123456789._tcp.local')
+            )).hex()
+            */
+            val query = HexDump.hexStringToByteArray("0000000000020001000000000d5f6e6d74313233343" +
+                    "536373839045f746370056c6f63616c00000c8001104e7364546573743132333435363738390" +
+                    "d5f6e6d74313233343536373839045f746370056c6f63616c00001080010d5f6e6d743132333" +
+                    "43536373839045f746370056c6f63616c00000c000100001194002b104e73645465737431323" +
+                    "33435363738390d5f6e6d74313233343536373839045f746370056c6f63616c00")
+            replaceServiceNameAndTypeWithTestSuffix(query)
+
+            val testSrcAddr = makeLinkLocalAddressOfOtherDeviceOnPrefix(testNetwork1.network)
+            nsResponder = NSResponder(packetReader, mapOf(
+                    testSrcAddr to MacAddress.fromString("01:02:03:04:05:06")
+            )).apply { start() }
+
+            packetReader.sendResponse(buildMdnsPacket(query, testSrcAddr))
+            // The reply is sent unicast to the source address. There may be announcements sent
+            // multicast around this time, so filter by destination address.
+            val reply = packetReader.pollForMdnsPacket { pkt ->
+                pkt.isReplyFor("$serviceName.$serviceType.local", DnsResolver.TYPE_TXT) &&
+                        !pkt.isReplyFor("$serviceType.local", DnsResolver.TYPE_PTR) &&
+                        pkt.dstAddr == testSrcAddr
+            }
+            assertNotNull(reply)
+
+            /*
+            Send a query with a known answer (TTL is less than half). Expect to receive a response
+            containing both PTR and TXT records.
+            Generated with:
+            scapy.raw(scapy.DNS(rd=0, qr=0, aa=0, qd =
+                    scapy.DNSQR(qname='_nmt123456789._tcp.local', qtype='PTR',
+                            qclass=0x8001) /
+                    scapy.DNSQR(qname='NsdTest123456789._nmt123456789._tcp.local', qtype='TXT',
+                            qclass=0x8001),
+                    an = scapy.DNSRR(rrname='_nmt123456789._tcp.local', type='PTR', ttl=2150,
+                            rdata='NsdTest123456789._nmt123456789._tcp.local')
+            )).hex()
+            */
+            val query2 = HexDump.hexStringToByteArray("0000000000020001000000000d5f6e6d7431323334" +
+                    "3536373839045f746370056c6f63616c00000c8001104e736454657374313233343536373839" +
+                    "0d5f6e6d74313233343536373839045f746370056c6f63616c00001080010d5f6e6d74313233" +
+                    "343536373839045f746370056c6f63616c00000c000100000866002b104e7364546573743132" +
+                    "333435363738390d5f6e6d74313233343536373839045f746370056c6f63616c00")
+            replaceServiceNameAndTypeWithTestSuffix(query2)
+
+            packetReader.sendResponse(buildMdnsPacket(query2, testSrcAddr))
+            // The reply is sent unicast to the source address. There may be announcements sent
+            // multicast around this time, so filter by destination address.
+            val reply2 = packetReader.pollForMdnsPacket { pkt ->
+                pkt.isReplyFor("$serviceName.$serviceType.local", DnsResolver.TYPE_TXT) &&
+                        pkt.isReplyFor("$serviceType.local", DnsResolver.TYPE_PTR) &&
+                        pkt.dstAddr == testSrcAddr
+            }
+            assertNotNull(reply2)
+        } cleanup {
+            nsResponder?.stop()
+            nsdManager.unregisterService(registrationRecord)
+            registrationRecord.expectCallback<ServiceUnregistered>()
+        }
+    }
+
+    @Test
+    fun testReplyWithMultipacketWhenKnownAnswerSuppressionFlagSet() {
+        // 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_known_answer_suppression", "1")
+        deviceConfigRule.setConfig(NAMESPACE_TETHERING, "test_nsd_unicast_reply_enabled", "1")
+
+        val si = makeTestServiceInfo(testNetwork1.network)
+
+        // Register service on testNetwork1
+        val registrationRecord = NsdRegistrationRecord()
+        var nsResponder: NSResponder? = null
+        tryTest {
+            registerService(registrationRecord, si)
+            val packetReader = TapPacketReader(Handler(handlerThread.looper),
+                    testNetwork1.iface.fileDescriptor.fileDescriptor, 1500 /* maxPacketSize */)
+            packetReader.startAsyncForTest()
+
+            handlerThread.waitForIdle(TIMEOUT_MS)
+            /*
+            Send a query with truncated bit set.
+            Generated with:
+            scapy.raw(scapy.DNS(rd=0, qr=0, aa=0, tc=1, qd=
+                    scapy.DNSQR(qname='_nmt123456789._tcp.local', qtype='PTR',
+                            qclass=0x8001) /
+                    scapy.DNSQR(qname='NsdTest123456789._nmt123456789._tcp.local', qtype='TXT',
+                            qclass=0x8001)
+            )).hex()
+            */
+            val query = HexDump.hexStringToByteArray("0000020000020000000000000d5f6e6d74313233343" +
+                    "536373839045f746370056c6f63616c00000c8001104e7364546573743132333435363738390" +
+                    "d5f6e6d74313233343536373839045f746370056c6f63616c0000108001")
+            replaceServiceNameAndTypeWithTestSuffix(query)
+            /*
+            Send a known answer packet (other service) with truncated bit set.
+            Generated with:
+            scapy.raw(scapy.DNS(rd=0, qr=0, aa=0, tc=1, qd=None,
+                    an = scapy.DNSRR(rrname='_test._tcp.local', type='PTR', ttl=4500,
+                            rdata='NsdTest._test._tcp.local')
+            )).hex()
+            */
+            val knownAnswer1 = HexDump.hexStringToByteArray("000002000000000100000000055f74657374" +
+                    "045f746370056c6f63616c00000c000100001194001a074e736454657374055f74657374045f" +
+                    "746370056c6f63616c00")
+            replaceServiceNameAndTypeWithTestSuffix(knownAnswer1)
+            /*
+            Send a known answer packet.
+            Generated with:
+            scapy.raw(scapy.DNS(rd=0, qr=0, aa=0, qd=None,
+                    an = scapy.DNSRR(rrname='_nmt123456789._tcp.local', type='PTR', ttl=4500,
+                            rdata='NsdTest123456789._nmt123456789._tcp.local')
+            )).hex()
+            */
+            val knownAnswer2 = HexDump.hexStringToByteArray("0000000000000001000000000d5f6e6d7431" +
+                    "3233343536373839045f746370056c6f63616c00000c000100001194002b104e736454657374" +
+                    "3132333435363738390d5f6e6d74313233343536373839045f746370056c6f63616c00")
+            replaceServiceNameAndTypeWithTestSuffix(knownAnswer2)
+
+            val testSrcAddr = makeLinkLocalAddressOfOtherDeviceOnPrefix(testNetwork1.network)
+            nsResponder = NSResponder(packetReader, mapOf(
+                    testSrcAddr to MacAddress.fromString("01:02:03:04:05:06")
+            )).apply { start() }
+
+            packetReader.sendResponse(buildMdnsPacket(query, testSrcAddr))
+            packetReader.sendResponse(buildMdnsPacket(knownAnswer1, testSrcAddr))
+            packetReader.sendResponse(buildMdnsPacket(knownAnswer2, testSrcAddr))
+            // The reply is sent unicast to the source address. There may be announcements sent
+            // multicast around this time, so filter by destination address.
+            val reply = packetReader.pollForMdnsPacket { pkt ->
+                pkt.isReplyFor("$serviceName.$serviceType.local", DnsResolver.TYPE_TXT) &&
+                        !pkt.isReplyFor("$serviceType.local", DnsResolver.TYPE_PTR) &&
+                        pkt.dstAddr == testSrcAddr
+            }
+            assertNotNull(reply)
+        } cleanup {
+            nsResponder?.stop()
+            nsdManager.unregisterService(registrationRecord)
+            registrationRecord.expectCallback<ServiceUnregistered>()
+        }
+    }
+
     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/net/TrafficStatsRateLimitCacheTest.kt b/tests/unit/java/com/android/server/net/TrafficStatsRateLimitCacheTest.kt
new file mode 100644
index 0000000..27e6f96
--- /dev/null
+++ b/tests/unit/java/com/android/server/net/TrafficStatsRateLimitCacheTest.kt
@@ -0,0 +1,89 @@
+/*
+ * Copyright (C) 2024 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.server.net
+
+import android.net.NetworkStats
+import com.android.testutils.DevSdkIgnoreRunner
+import java.time.Clock
+import kotlin.test.assertEquals
+import kotlin.test.assertNull
+import org.junit.Test
+import org.junit.runner.RunWith
+import org.mockito.Mockito.mock
+import org.mockito.Mockito.`when`
+
+@RunWith(DevSdkIgnoreRunner::class)
+class TrafficStatsRateLimitCacheTest {
+    companion object {
+        private const val expiryDurationMs = 1000L
+    }
+
+    private val clock = mock(Clock::class.java)
+    private val entry = mock(NetworkStats.Entry::class.java)
+    private val cache = TrafficStatsRateLimitCache(clock, expiryDurationMs)
+
+    @Test
+    fun testGet_returnsEntryIfNotExpired() {
+        cache.put("iface", 2, entry)
+        `when`(clock.millis()).thenReturn(500L) // Set clock to before expiry
+        val result = cache.get("iface", 2)
+        assertEquals(entry, result)
+    }
+
+    @Test
+    fun testGet_returnsNullIfExpired() {
+        cache.put("iface", 2, entry)
+        `when`(clock.millis()).thenReturn(2000L) // Set clock to after expiry
+        assertNull(cache.get("iface", 2))
+    }
+
+    @Test
+    fun testGet_returnsNullForNonExistentKey() {
+        val result = cache.get("otherIface", 99)
+        assertNull(result)
+    }
+
+    @Test
+    fun testPutAndGet_retrievesCorrectEntryForDifferentKeys() {
+        val entry1 = mock(NetworkStats.Entry::class.java)
+        val entry2 = mock(NetworkStats.Entry::class.java)
+
+        cache.put("iface1", 2, entry1)
+        cache.put("iface2", 4, entry2)
+
+        assertEquals(entry1, cache.get("iface1", 2))
+        assertEquals(entry2, cache.get("iface2", 4))
+    }
+
+    @Test
+    fun testPut_overridesExistingEntry() {
+        val entry1 = mock(NetworkStats.Entry::class.java)
+        val entry2 = mock(NetworkStats.Entry::class.java)
+
+        cache.put("iface", 2, entry1)
+        cache.put("iface", 2, entry2) // Put with the same key
+
+        assertEquals(entry2, cache.get("iface", 2))
+    }
+
+    @Test
+    fun testClear() {
+        cache.put("iface", 2, entry)
+        cache.clear()
+        assertNull(cache.get("iface", 2))
+    }
+}