Merge changes I82d3bee0,I9c9413d7 am: deb4eb5d05 am: 51c3d6a8bf am: 0cf31d4d6d am: 20fa45e3a9
am: d14c177136

Change-Id: I100ba259bcebf0ed0b9192ed32a038457d2a2283
diff --git a/core/java/android/net/ITetheringStatsProvider.aidl b/core/java/android/net/ITetheringStatsProvider.aidl
index 769086d..1aeabc1 100644
--- a/core/java/android/net/ITetheringStatsProvider.aidl
+++ b/core/java/android/net/ITetheringStatsProvider.aidl
@@ -19,7 +19,7 @@
 import android.net.NetworkStats;
 
 /**
- * Interface that allows NetworkManagementService to query for tethering statistics.
+ * Interface for NetworkManagementService to query tethering statistics and set data limits.
  *
  * TODO: this does not really need to be an interface since Tethering runs in the same process
  * as NetworkManagementService. Consider refactoring Tethering to use direct access to
@@ -29,5 +29,14 @@
  * @hide
  */
 interface ITetheringStatsProvider {
+    // Returns cumulative statistics for all tethering sessions since boot, on all upstreams.
     NetworkStats getTetherStats();
+
+    // Sets the interface quota for the specified upstream interface. This is defined as the number
+    // of bytes, starting from zero and counting from now, after which data should stop being
+    // forwarded to/from the specified upstream. A value of QUOTA_UNLIMITED means there is no limit.
+    void setInterfaceQuota(String iface, long quotaBytes);
+
+    // Indicates that no data usage limit is set.
+    const int QUOTA_UNLIMITED = -1;
 }
diff --git a/services/core/java/com/android/server/NetworkManagementService.java b/services/core/java/com/android/server/NetworkManagementService.java
index 13aca87..796b425 100644
--- a/services/core/java/com/android/server/NetworkManagementService.java
+++ b/services/core/java/com/android/server/NetworkManagementService.java
@@ -1567,6 +1567,17 @@
             } catch (NativeDaemonConnectorException e) {
                 throw e.rethrowAsParcelableException();
             }
+
+            synchronized (mTetheringStatsProviders) {
+                for (ITetheringStatsProvider provider : mTetheringStatsProviders.keySet()) {
+                    try {
+                        provider.setInterfaceQuota(iface, quotaBytes);
+                    } catch (RemoteException e) {
+                        Log.e(TAG, "Problem setting tethering data limit on provider " +
+                                mTetheringStatsProviders.get(provider) + ": " + e);
+                    }
+                }
+            }
         }
     }
 
@@ -1593,6 +1604,17 @@
             } catch (NativeDaemonConnectorException e) {
                 throw e.rethrowAsParcelableException();
             }
+
+            synchronized (mTetheringStatsProviders) {
+                for (ITetheringStatsProvider provider : mTetheringStatsProviders.keySet()) {
+                    try {
+                        provider.setInterfaceQuota(iface, ITetheringStatsProvider.QUOTA_UNLIMITED);
+                    } catch (RemoteException e) {
+                        Log.e(TAG, "Problem removing tethering data limit on provider " +
+                                mTetheringStatsProviders.get(provider) + ": " + e);
+                    }
+                }
+            }
         }
     }
 
@@ -1864,6 +1886,11 @@
             }
             return stats;
         }
+
+        @Override
+        public void setInterfaceQuota(String iface, long quotaBytes) {
+            // Do nothing. netd is already informed of quota changes in setInterfaceQuota.
+        }
     }
 
     @Override
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 1a5ff77..55e290a 100644
--- a/services/core/java/com/android/server/connectivity/tethering/OffloadController.java
+++ b/services/core/java/com/android/server/connectivity/tethering/OffloadController.java
@@ -46,7 +46,6 @@
 import java.util.HashSet;
 import java.util.Objects;
 import java.util.Set;
-import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.TimeUnit;
 
 /**
@@ -58,8 +57,6 @@
 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;
@@ -76,9 +73,17 @@
     private Set<String> mLastLocalPrefixStrs;
 
     // Maps upstream interface names to offloaded traffic statistics.
+    // Always contains the latest value received from the hardware for each interface, regardless of
+    // whether offload is currently running on that interface.
     private HashMap<String, OffloadHardwareInterface.ForwardedStats>
             mForwardedStats = new HashMap<>();
 
+    // Maps upstream interface names to interface quotas.
+    // Always contains the latest value received from the framework for each interface, regardless
+    // of whether offload is currently running (or is even supported) on that interface. Only
+    // includes upstream interfaces that have a quota set.
+    private HashMap<String, Long> mInterfaceQuotas = new HashMap<>();
+
     public OffloadController(Handler h, OffloadHardwareInterface hwi,
             ContentResolver contentResolver, INetworkManagementService nms, SharedLog log) {
         mHandler = h;
@@ -177,36 +182,38 @@
         @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;
+            // We can't just post to mHandler because we are mostly (but not always) called by
+            // NetworkStatsService#performPollLocked, which is (currently) on the same thread as us.
+            mHandler.runWithScissors(() -> {
+                NetworkStats.Entry entry = new NetworkStats.Entry();
+                entry.set = SET_DEFAULT;
+                entry.tag = TAG_NONE;
+                entry.uid = UID_TETHERING;
 
-                    updateStatsForCurrentUpstream();
+                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();
+                for (String iface : mForwardedStats.keySet()) {
+                    entry.iface = iface;
+                    entry.rxBytes = mForwardedStats.get(iface).rxBytes;
+                    entry.txBytes = mForwardedStats.get(iface).txBytes;
+                    stats.addValues(entry);
                 }
-            });
-
-            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");
-            }
+            }, 0);
 
             return stats;
         }
+
+        public void setInterfaceQuota(String iface, long quotaBytes) {
+            mHandler.post(() -> {
+                if (quotaBytes == ITetheringStatsProvider.QUOTA_UNLIMITED) {
+                    mInterfaceQuotas.remove(iface);
+                } else {
+                    mInterfaceQuotas.put(iface, quotaBytes);
+                }
+                maybeUpdateDataLimit(iface);
+            });
+        }
     }
 
     private void maybeUpdateStats(String iface) {
@@ -220,6 +227,22 @@
         mForwardedStats.get(iface).add(mHwInterface.getForwardedStats(iface));
     }
 
+    private boolean maybeUpdateDataLimit(String iface) {
+        // setDataLimit may only be called while offload is occuring on this upstream.
+        if (!started() ||
+                mUpstreamLinkProperties == null ||
+                !TextUtils.equals(iface, mUpstreamLinkProperties.getInterfaceName())) {
+            return true;
+        }
+
+        Long limit = mInterfaceQuotas.get(iface);
+        if (limit == null) {
+            limit = Long.MAX_VALUE;
+        }
+
+        return mHwInterface.setDataLimit(iface, limit);
+    }
+
     private void updateStatsForCurrentUpstream() {
         if (mUpstreamLinkProperties != null) {
             maybeUpdateStats(mUpstreamLinkProperties.getInterfaceName());
@@ -309,8 +332,21 @@
             }
         }
 
-        return mHwInterface.setUpstreamParameters(
+        boolean success = mHwInterface.setUpstreamParameters(
                 iface, v4addr, v4gateway, (v6gateways.isEmpty() ? null : v6gateways));
+
+        if (!success) {
+           return success;
+        }
+
+        // Data limits can only be set once offload is running on the upstream.
+        success = maybeUpdateDataLimit(iface);
+        if (!success) {
+            mLog.log("Setting data limit for " + iface + " failed, disabling offload.");
+            stop();
+        }
+
+        return success;
     }
 
     private boolean computeAndPushLocalPrefixes() {
diff --git a/services/core/java/com/android/server/connectivity/tethering/OffloadHardwareInterface.java b/services/core/java/com/android/server/connectivity/tethering/OffloadHardwareInterface.java
index 25fab9e..cf5685d 100644
--- a/services/core/java/com/android/server/connectivity/tethering/OffloadHardwareInterface.java
+++ b/services/core/java/com/android/server/connectivity/tethering/OffloadHardwareInterface.java
@@ -188,6 +188,27 @@
         return results.success;
     }
 
+    public boolean setDataLimit(String iface, long limit) {
+
+        final String logmsg = String.format("setDataLimit(%s, %d)", iface, limit);
+
+        final CbResults results = new CbResults();
+        try {
+            mOffloadControl.setDataLimit(
+                    iface, limit,
+                    (boolean success, String errMsg) -> {
+                        results.success = success;
+                        results.errMsg = errMsg;
+                    });
+        } catch (RemoteException e) {
+            record(logmsg, e);
+            return false;
+        }
+
+        record(logmsg, results);
+        return results.success;
+    }
+
     public boolean setUpstreamParameters(
             String iface, String v4addr, String v4gateway, ArrayList<String> v6gws) {
         iface = (iface != null) ? iface : NO_INTERFACE_NAME;
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 dcb9723..c4965a0 100644
--- a/tests/net/java/com/android/server/connectivity/tethering/OffloadControllerTest.java
+++ b/tests/net/java/com/android/server/connectivity/tethering/OffloadControllerTest.java
@@ -25,6 +25,7 @@
 import static org.junit.Assert.assertTrue;
 import static org.junit.Assert.fail;
 import static org.mockito.Matchers.any;
+import static org.mockito.Matchers.anyLong;
 import static org.mockito.Matchers.anyObject;
 import static org.mockito.Matchers.anyString;
 import static org.mockito.Matchers.eq;
@@ -45,6 +46,7 @@
 import android.net.NetworkStats;
 import android.net.RouteInfo;
 import android.net.util.SharedLog;
+import android.os.ConditionVariable;
 import android.os.Handler;
 import android.os.Looper;
 import android.os.INetworkManagementService;
@@ -110,6 +112,12 @@
         Settings.Global.putInt(mContentResolver, TETHER_OFFLOAD_DISABLED, 0);
     }
 
+    private void waitForIdle() {
+        ConditionVariable cv = new ConditionVariable();
+        new Handler(Looper.getMainLooper()).post(() -> { cv.open(); });
+        cv.block();
+    }
+
     private OffloadController makeOffloadController() throws Exception {
         OffloadController offload = new OffloadController(new Handler(Looper.getMainLooper()),
                 mHardware, mContentResolver, mNMService, new SharedLog("test"));
@@ -417,4 +425,68 @@
         entry = stats.getValues(ethernetPosition, entry);
         assertNetworkStats(ethernetIface, ethernetStats, entry);
     }
+
+    @Test
+    public void testSetInterfaceQuota() throws Exception {
+        setupFunctioningHardwareInterface();
+        enableOffload();
+
+        final OffloadController offload = makeOffloadController();
+        offload.start();
+
+        final String ethernetIface = "eth1";
+        final String mobileIface = "rmnet_data0";
+        final long ethernetLimit = 12345;
+        final long mobileLimit = 12345678;
+
+        final LinkProperties lp = new LinkProperties();
+        lp.setInterfaceName(ethernetIface);
+        offload.setUpstreamLinkProperties(lp);
+
+        ITetheringStatsProvider provider = mTetherStatsProviderCaptor.getValue();
+        final InOrder inOrder = inOrder(mHardware);
+        when(mHardware.setUpstreamParameters(any(), any(), any(), any())).thenReturn(true);
+        when(mHardware.setDataLimit(anyString(), anyLong())).thenReturn(true);
+
+        // Applying an interface quota to the current upstream immediately sends it to the hardware.
+        provider.setInterfaceQuota(ethernetIface, ethernetLimit);
+        waitForIdle();
+        inOrder.verify(mHardware).setDataLimit(ethernetIface, ethernetLimit);
+        inOrder.verifyNoMoreInteractions();
+
+        // Applying an interface quota to another upstream does not take any immediate action.
+        provider.setInterfaceQuota(mobileIface, mobileLimit);
+        waitForIdle();
+        inOrder.verify(mHardware, never()).setDataLimit(anyString(), anyLong());
+
+        // Switching to that upstream causes the quota to be applied if the parameters were applied
+        // correctly.
+        lp.setInterfaceName(mobileIface);
+        offload.setUpstreamLinkProperties(lp);
+        waitForIdle();
+        inOrder.verify(mHardware).setDataLimit(mobileIface, mobileLimit);
+
+        // Setting a limit of ITetheringStatsProvider.QUOTA_UNLIMITED causes the limit to be set
+        // to Long.MAX_VALUE.
+        provider.setInterfaceQuota(mobileIface, ITetheringStatsProvider.QUOTA_UNLIMITED);
+        waitForIdle();
+        inOrder.verify(mHardware).setDataLimit(mobileIface, Long.MAX_VALUE);
+
+        // If setting upstream parameters fails, then the data limit is not set.
+        when(mHardware.setUpstreamParameters(any(), any(), any(), any())).thenReturn(false);
+        lp.setInterfaceName(ethernetIface);
+        offload.setUpstreamLinkProperties(lp);
+        provider.setInterfaceQuota(mobileIface, mobileLimit);
+        waitForIdle();
+        inOrder.verify(mHardware, never()).setDataLimit(anyString(), anyLong());
+
+        // If setting the data limit fails while changing upstreams, offload is stopped.
+        when(mHardware.setUpstreamParameters(any(), any(), any(), any())).thenReturn(true);
+        when(mHardware.setDataLimit(anyString(), anyLong())).thenReturn(false);
+        lp.setInterfaceName(mobileIface);
+        offload.setUpstreamLinkProperties(lp);
+        provider.setInterfaceQuota(mobileIface, mobileLimit);
+        waitForIdle();
+        inOrder.verify(mHardware).stopOffloadControl();
+    }
 }