Fetch tethering offload stats.

Make tethering offload register an ITetheringStatsProvider and
fetch tethering stats from the hardware.

Currently we fetch stats in the following cases:

1. Just after changing upstreams, we fetch stats from the
   previous upstream.
2. When we are polled by NetworkStatsService.

Bug: 29337859
Bug: 32163131
Test: builds, boots
Test: stats appear in tethering logs
Change-Id: If744f2e06cb6a3095a40199936b9afb76eff7b56

4 files changed, 190 insertions, 17 deletions

diff --git a/services/core/java/com/android/server/connectivity/Tethering.java b/services/core/java/com/android/server/connectivity/Tethering.java
index 1fb944fda7c9..c542f75ff685 100644
--- a/services/core/java/com/android/server/connectivity/Tethering.java
+++ b/services/core/java/com/android/server/connectivity/Tethering.java
@@ -214,7 +214,7 @@ public class Tethering extends BaseNetworkObserver {
         final Handler smHandler = mTetherMasterSM.getHandler();
         mOffloadController = new OffloadController(smHandler,
                 deps.getOffloadHardwareInterface(smHandler, mLog),
-                mContext.getContentResolver(),
+                mContext.getContentResolver(), mNMService,
                 mLog);
         mUpstreamNetworkMonitor = new UpstreamNetworkMonitor(
                 mContext, mTetherMasterSM, mLog, TetherMasterSM.EVENT_UPSTREAM_CALLBACK);
diff --git a/services/core/java/com/android/server/connectivity/tethering/OffloadController.java b/services/core/java/com/android/server/connectivity/tethering/OffloadController.java
index b47386705a36..28d390f35202 100644
--- a/services/core/java/com/android/server/connectivity/tethering/OffloadController.java
+++ b/services/core/java/com/android/server/connectivity/tethering/OffloadController.java
@@ -16,24 +16,36 @@
 
 package com.android.server.connectivity.tethering;
 
+import static android.net.NetworkStats.SET_DEFAULT;
+import static android.net.NetworkStats.TAG_NONE;
+import static android.net.TrafficStats.UID_TETHERING;
 import static android.provider.Settings.Global.TETHER_OFFLOAD_DISABLED;
 
 import android.content.ContentResolver;
+import android.net.ITetheringStatsProvider;
 import android.net.IpPrefix;
 import android.net.LinkAddress;
 import android.net.LinkProperties;
+import android.net.NetworkStats;
 import android.net.RouteInfo;
 import android.net.util.SharedLog;
 import android.os.Handler;
+import android.os.INetworkManagementService;
+import android.os.RemoteException;
+import android.os.SystemClock;
 import android.provider.Settings;
+import android.text.TextUtils;
 
 import java.net.Inet4Address;
 import java.net.Inet6Address;
 import java.net.InetAddress;
 import java.util.ArrayList;
+import java.util.HashMap;
 import java.util.HashSet;
 import java.util.Objects;
 import java.util.Set;
+import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.TimeUnit;
 
 /**
  * A class to encapsulate the business logic of programming the tethering
@@ -44,6 +56,8 @@ import java.util.Set;
 public class OffloadController {
     private static final String TAG = OffloadController.class.getSimpleName();
 
+    private static final int STATS_FETCH_TIMEOUT_MS = 1000;
+
     private final Handler mHandler;
     private final OffloadHardwareInterface mHwInterface;
     private final ContentResolver mContentResolver;
@@ -59,14 +73,25 @@ public class OffloadController {
     // prefixes representing only the locally-assigned IP addresses.
     private Set<String> mLastLocalPrefixStrs;
 
+    // Maps upstream interface names to offloaded traffic statistics.
+    private HashMap<String, OffloadHardwareInterface.ForwardedStats>
+            mForwardedStats = new HashMap<>();
+
     public OffloadController(Handler h, OffloadHardwareInterface hwi,
-            ContentResolver contentResolver, SharedLog log) {
+            ContentResolver contentResolver, INetworkManagementService nms, SharedLog log) {
         mHandler = h;
         mHwInterface = hwi;
         mContentResolver = contentResolver;
         mLog = log.forSubComponent(TAG);
         mExemptPrefixes = new HashSet<>();
         mLastLocalPrefixStrs = new HashSet<>();
+
+        try {
+            nms.registerTetheringStatsProvider(
+                    new OffloadTetheringStatsProvider(), getClass().getSimpleName());
+        } catch (RemoteException e) {
+            mLog.e("Cannot register offload stats provider: " + e);
+        }
     }
 
     public void start() {
@@ -138,6 +163,7 @@ public class OffloadController {
 
     public void stop() {
         final boolean wasStarted = started();
+        updateStatsForCurrentUpstream();
         mUpstreamLinkProperties = null;
         mHwInterface.stopOffloadControl();
         mControlInitialized = false;
@@ -145,16 +171,76 @@ public class OffloadController {
         if (wasStarted) mLog.log("tethering offload stopped");
     }
 
+    private class OffloadTetheringStatsProvider extends ITetheringStatsProvider.Stub {
+        @Override
+        public NetworkStats getTetherStats() {
+            NetworkStats stats = new NetworkStats(SystemClock.elapsedRealtime(), 0);
+            CountDownLatch latch = new CountDownLatch(1);
+
+            mHandler.post(() -> {
+                try {
+                    NetworkStats.Entry entry = new NetworkStats.Entry();
+                    entry.set = SET_DEFAULT;
+                    entry.tag = TAG_NONE;
+                    entry.uid = UID_TETHERING;
+
+                    updateStatsForCurrentUpstream();
+
+                    for (String iface : mForwardedStats.keySet()) {
+                        entry.iface = iface;
+                        entry.rxBytes = mForwardedStats.get(iface).rxBytes;
+                        entry.txBytes = mForwardedStats.get(iface).txBytes;
+                        stats.addValues(entry);
+                    }
+                } finally {
+                    latch.countDown();
+                }
+            });
+
+            try {
+                latch.await(STATS_FETCH_TIMEOUT_MS, TimeUnit.MILLISECONDS);
+            } catch (InterruptedException e) {
+                mLog.e("Tethering stats fetch timed out after " + STATS_FETCH_TIMEOUT_MS + "ms");
+            }
+
+            return stats;
+        }
+    }
+
+    private void maybeUpdateStats(String iface) {
+        if (TextUtils.isEmpty(iface)) {
+            return;
+        }
+
+        if (!mForwardedStats.containsKey(iface)) {
+            mForwardedStats.put(iface, new OffloadHardwareInterface.ForwardedStats());
+        }
+        mForwardedStats.get(iface).add(mHwInterface.getForwardedStats(iface));
+    }
+
+    private void updateStatsForCurrentUpstream() {
+        if (mUpstreamLinkProperties != null) {
+            maybeUpdateStats(mUpstreamLinkProperties.getInterfaceName());
+        }
+    }
+
     public void setUpstreamLinkProperties(LinkProperties lp) {
         if (!started() || Objects.equals(mUpstreamLinkProperties, lp)) return;
 
+        String prevUpstream = (mUpstreamLinkProperties != null) ?
+                mUpstreamLinkProperties.getInterfaceName() : null;
+
         mUpstreamLinkProperties = (lp != null) ? new LinkProperties(lp) : null;
+
         // TODO: examine return code and decide what to do if programming
         // upstream parameters fails (probably just wait for a subsequent
         // onOffloadEvent() callback to tell us offload is available again and
         // then reapply all state).
         computeAndPushLocalPrefixes();
         pushUpstreamParameters();
+
+        // Update stats after we've told the hardware to change routing so we don't miss packets.
+        maybeUpdateStats(prevUpstream);
     }
 
     public void setLocalPrefixes(Set<IpPrefix> localPrefixes) {
diff --git a/tests/net/java/com/android/server/connectivity/TetheringTest.java b/tests/net/java/com/android/server/connectivity/TetheringTest.java
index acf9e8f71718..a115146486a4 100644
--- a/tests/net/java/com/android/server/connectivity/TetheringTest.java
+++ b/tests/net/java/com/android/server/connectivity/TetheringTest.java
@@ -178,6 +178,7 @@ public class TetheringTest {
         mTethering = new Tethering(mServiceContext, mNMService, mStatsService, mPolicyManager,
                                    mLooper.getLooper(), mSystemProperties,
                                    mTetheringDependencies);
+        verify(mNMService).registerTetheringStatsProvider(any(), anyString());
     }
 
     @After
diff --git a/tests/net/java/com/android/server/connectivity/tethering/OffloadControllerTest.java b/tests/net/java/com/android/server/connectivity/tethering/OffloadControllerTest.java
index 0e4a36ccfc7e..dcb9723fa5e2 100644
--- a/tests/net/java/com/android/server/connectivity/tethering/OffloadControllerTest.java
+++ b/tests/net/java/com/android/server/connectivity/tethering/OffloadControllerTest.java
@@ -16,26 +16,38 @@
 
 package com.android.server.connectivity.tethering;
 
+import static android.net.NetworkStats.SET_DEFAULT;
+import static android.net.NetworkStats.TAG_NONE;
+import static android.net.TrafficStats.UID_TETHERING;
 import static android.provider.Settings.Global.TETHER_OFFLOAD_DISABLED;
+import static com.android.server.connectivity.tethering.OffloadHardwareInterface.ForwardedStats;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertTrue;
 import static org.junit.Assert.fail;
 import static org.mockito.Matchers.any;
 import static org.mockito.Matchers.anyObject;
+import static org.mockito.Matchers.anyString;
 import static org.mockito.Matchers.eq;
+import static org.mockito.Mockito.doNothing;
 import static org.mockito.Mockito.inOrder;
 import static org.mockito.Mockito.never;
 import static org.mockito.Mockito.reset;
 import static org.mockito.Mockito.times;
+import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.when;
 
 import android.content.Context;
 import android.content.pm.ApplicationInfo;
+import android.net.ITetheringStatsProvider;
 import android.net.IpPrefix;
 import android.net.LinkAddress;
 import android.net.LinkProperties;
+import android.net.NetworkStats;
 import android.net.RouteInfo;
 import android.net.util.SharedLog;
+import android.os.Handler;
+import android.os.Looper;
+import android.os.INetworkManagementService;
 import android.provider.Settings;
 import android.provider.Settings.SettingNotFoundException;
 
@@ -66,11 +78,14 @@ public class OffloadControllerTest {
     @Mock private OffloadHardwareInterface mHardware;
     @Mock private ApplicationInfo mApplicationInfo;
     @Mock private Context mContext;
+    @Mock private INetworkManagementService mNMService;
     private final ArgumentCaptor<ArrayList> mStringArrayCaptor =
             ArgumentCaptor.forClass(ArrayList.class);
+    private final ArgumentCaptor<ITetheringStatsProvider.Stub> mTetherStatsProviderCaptor =
+            ArgumentCaptor.forClass(ITetheringStatsProvider.Stub.class);
     private MockContentResolver mContentResolver;
 
-    @Before public void setUp() throws Exception {
+    @Before public void setUp() {
         MockitoAnnotations.initMocks(this);
         when(mContext.getApplicationInfo()).thenReturn(mApplicationInfo);
         when(mContext.getPackageName()).thenReturn("OffloadControllerTest");
@@ -88,14 +103,23 @@ public class OffloadControllerTest {
         when(mHardware.initOffloadConfig()).thenReturn(true);
         when(mHardware.initOffloadControl(any(OffloadHardwareInterface.ControlCallback.class)))
                 .thenReturn(true);
+        when(mHardware.getForwardedStats(any())).thenReturn(new ForwardedStats());
     }
 
     private void enableOffload() {
         Settings.Global.putInt(mContentResolver, TETHER_OFFLOAD_DISABLED, 0);
     }
 
+    private OffloadController makeOffloadController() throws Exception {
+        OffloadController offload = new OffloadController(new Handler(Looper.getMainLooper()),
+                mHardware, mContentResolver, mNMService, new SharedLog("test"));
+        verify(mNMService).registerTetheringStatsProvider(
+                mTetherStatsProviderCaptor.capture(), anyString());
+        return offload;
+    }
+
     @Test
-    public void testNoSettingsValueDefaultDisabledDoesNotStart() {
+    public void testNoSettingsValueDefaultDisabledDoesNotStart() throws Exception {
         setupFunctioningHardwareInterface();
         when(mHardware.getDefaultTetherOffloadDisabled()).thenReturn(1);
         try {
@@ -103,8 +127,7 @@ public class OffloadControllerTest {
             fail();
         } catch (SettingNotFoundException expected) {}
 
-        final OffloadController offload =
-                new OffloadController(null, mHardware, mContentResolver, new SharedLog("test"));
+        final OffloadController offload = makeOffloadController();
         offload.start();
 
         final InOrder inOrder = inOrder(mHardware);
@@ -116,7 +139,7 @@ public class OffloadControllerTest {
     }
 
     @Test
-    public void testNoSettingsValueDefaultEnabledDoesStart() {
+    public void testNoSettingsValueDefaultEnabledDoesStart() throws Exception {
         setupFunctioningHardwareInterface();
         when(mHardware.getDefaultTetherOffloadDisabled()).thenReturn(0);
         try {
@@ -124,8 +147,7 @@ public class OffloadControllerTest {
             fail();
         } catch (SettingNotFoundException expected) {}
 
-        final OffloadController offload =
-                new OffloadController(null, mHardware, mContentResolver, new SharedLog("test"));
+        final OffloadController offload = makeOffloadController();
         offload.start();
 
         final InOrder inOrder = inOrder(mHardware);
@@ -137,12 +159,11 @@ public class OffloadControllerTest {
     }
 
     @Test
-    public void testSettingsAllowsStart() {
+    public void testSettingsAllowsStart() throws Exception {
         setupFunctioningHardwareInterface();
         Settings.Global.putInt(mContentResolver, TETHER_OFFLOAD_DISABLED, 0);
 
-        final OffloadController offload =
-                new OffloadController(null, mHardware, mContentResolver, new SharedLog("test"));
+        final OffloadController offload = makeOffloadController();
         offload.start();
 
         final InOrder inOrder = inOrder(mHardware);
@@ -154,12 +175,11 @@ public class OffloadControllerTest {
     }
 
     @Test
-    public void testSettingsDisablesStart() {
+    public void testSettingsDisablesStart() throws Exception {
         setupFunctioningHardwareInterface();
         Settings.Global.putInt(mContentResolver, TETHER_OFFLOAD_DISABLED, 1);
 
-        final OffloadController offload =
-                new OffloadController(null, mHardware, mContentResolver, new SharedLog("test"));
+        final OffloadController offload = makeOffloadController();
         offload.start();
 
         final InOrder inOrder = inOrder(mHardware);
@@ -174,8 +194,7 @@ public class OffloadControllerTest {
         setupFunctioningHardwareInterface();
         enableOffload();
 
-        final OffloadController offload =
-                new OffloadController(null, mHardware, mContentResolver, new SharedLog("test"));
+        final OffloadController offload = makeOffloadController();
         offload.start();
 
         final InOrder inOrder = inOrder(mHardware);
@@ -240,6 +259,7 @@ public class OffloadControllerTest {
         inOrder.verify(mHardware, never()).setLocalPrefixes(mStringArrayCaptor.capture());
         inOrder.verify(mHardware, times(1)).setUpstreamParameters(
                 eq(testIfName), eq(ipv4Addr), eq(null), eq(null));
+        inOrder.verify(mHardware, times(1)).getForwardedStats(eq(testIfName));
         inOrder.verifyNoMoreInteractions();
 
         final String ipv4Gateway = "192.0.2.1";
@@ -249,6 +269,7 @@ public class OffloadControllerTest {
         inOrder.verify(mHardware, never()).setLocalPrefixes(mStringArrayCaptor.capture());
         inOrder.verify(mHardware, times(1)).setUpstreamParameters(
                 eq(testIfName), eq(ipv4Addr), eq(ipv4Gateway), eq(null));
+        inOrder.verify(mHardware, times(1)).getForwardedStats(eq(testIfName));
         inOrder.verifyNoMoreInteractions();
 
         final String ipv6Gw1 = "fe80::cafe";
@@ -258,6 +279,7 @@ public class OffloadControllerTest {
         inOrder.verify(mHardware, never()).setLocalPrefixes(mStringArrayCaptor.capture());
         inOrder.verify(mHardware, times(1)).setUpstreamParameters(
                 eq(testIfName), eq(ipv4Addr), eq(ipv4Gateway), mStringArrayCaptor.capture());
+        inOrder.verify(mHardware, times(1)).getForwardedStats(eq(testIfName));
         ArrayList<String> v6gws = mStringArrayCaptor.getValue();
         assertEquals(1, v6gws.size());
         assertTrue(v6gws.contains(ipv6Gw1));
@@ -270,6 +292,7 @@ public class OffloadControllerTest {
         inOrder.verify(mHardware, never()).setLocalPrefixes(mStringArrayCaptor.capture());
         inOrder.verify(mHardware, times(1)).setUpstreamParameters(
                 eq(testIfName), eq(ipv4Addr), eq(ipv4Gateway), mStringArrayCaptor.capture());
+        inOrder.verify(mHardware, times(1)).getForwardedStats(eq(testIfName));
         v6gws = mStringArrayCaptor.getValue();
         assertEquals(2, v6gws.size());
         assertTrue(v6gws.contains(ipv6Gw1));
@@ -287,6 +310,7 @@ public class OffloadControllerTest {
         inOrder.verify(mHardware, never()).setLocalPrefixes(mStringArrayCaptor.capture());
         inOrder.verify(mHardware, times(1)).setUpstreamParameters(
                 eq(testIfName), eq(ipv4Addr), eq(ipv4Gateway), mStringArrayCaptor.capture());
+        inOrder.verify(mHardware, times(1)).getForwardedStats(eq(testIfName));
         v6gws = mStringArrayCaptor.getValue();
         assertEquals(2, v6gws.size());
         assertTrue(v6gws.contains(ipv6Gw1));
@@ -321,6 +345,7 @@ public class OffloadControllerTest {
         assertEquals(2, v6gws.size());
         assertTrue(v6gws.contains(ipv6Gw1));
         assertTrue(v6gws.contains(ipv6Gw2));
+        inOrder.verify(mHardware, times(1)).getForwardedStats(eq(testIfName));
         inOrder.verifyNoMoreInteractions();
 
         // Completely identical LinkProperties updates are de-duped.
@@ -331,4 +356,65 @@ public class OffloadControllerTest {
                 anyObject(), anyObject(), anyObject(), anyObject());
         inOrder.verifyNoMoreInteractions();
     }
+
+    private void assertNetworkStats(String iface, ForwardedStats stats, NetworkStats.Entry entry) {
+        assertEquals(iface, entry.iface);
+        assertEquals(stats.rxBytes, entry.rxBytes);
+        assertEquals(stats.txBytes, entry.txBytes);
+        assertEquals(SET_DEFAULT, entry.set);
+        assertEquals(TAG_NONE, entry.tag);
+        assertEquals(UID_TETHERING, entry.uid);
+    }
+
+    @Test
+    public void testGetForwardedStats() throws Exception {
+        setupFunctioningHardwareInterface();
+        enableOffload();
+
+        final OffloadController offload = makeOffloadController();
+        offload.start();
+
+        final String ethernetIface = "eth1";
+        final String mobileIface = "rmnet_data0";
+
+        ForwardedStats ethernetStats = new ForwardedStats();
+        ethernetStats.rxBytes = 12345;
+        ethernetStats.txBytes = 54321;
+
+        ForwardedStats mobileStats = new ForwardedStats();
+        mobileStats.rxBytes = 999;
+        mobileStats.txBytes = 99999;
+
+        when(mHardware.getForwardedStats(eq(ethernetIface))).thenReturn(ethernetStats);
+        when(mHardware.getForwardedStats(eq(mobileIface))).thenReturn(mobileStats);
+
+        final LinkProperties lp = new LinkProperties();
+        lp.setInterfaceName(ethernetIface);
+        offload.setUpstreamLinkProperties(lp);
+
+        lp.setInterfaceName(mobileIface);
+        offload.setUpstreamLinkProperties(lp);
+
+        lp.setInterfaceName(ethernetIface);
+        offload.setUpstreamLinkProperties(lp);
+
+        ethernetStats.rxBytes = 100000;
+        ethernetStats.txBytes = 100000;
+        offload.setUpstreamLinkProperties(null);
+
+        NetworkStats stats = mTetherStatsProviderCaptor.getValue().getTetherStats();
+        assertEquals(2, stats.size());
+
+        NetworkStats.Entry entry = null;
+        int ethernetPosition = ethernetIface.equals(stats.getValues(0, entry).iface) ? 0 : 1;
+        int mobilePosition = 1 - ethernetPosition;
+
+        entry = stats.getValues(mobilePosition, entry);
+        assertNetworkStats(mobileIface, mobileStats, entry);
+
+        ethernetStats.rxBytes = 12345 + 100000;
+        ethernetStats.txBytes = 54321 + 100000;
+        entry = stats.getValues(ethernetPosition, entry);
+        assertNetworkStats(ethernetIface, ethernetStats, entry);
+    }
 }