Merge "Hack and ship: NetworkStats edition." into lmp-dev

2 files changed, 72 insertions, 7 deletions

diff --git a/core/java/android/net/LinkProperties.java b/core/java/android/net/LinkProperties.java
index 8be5cf8bd19e..47b74ab4d23f 100644
--- a/core/java/android/net/LinkProperties.java
+++ b/core/java/android/net/LinkProperties.java
@@ -16,6 +16,7 @@
 
 package android.net;
 
+import android.annotation.NonNull;
 import android.net.ProxyInfo;
 import android.os.Parcelable;
 import android.os.Parcel;
@@ -24,7 +25,6 @@ import android.text.TextUtils;
 import java.net.InetAddress;
 import java.net.Inet4Address;
 import java.net.Inet6Address;
-
 import java.net.UnknownHostException;
 import java.util.ArrayList;
 import java.util.Collection;
@@ -480,10 +480,13 @@ public final class LinkProperties implements Parcelable {
      * Returns all the links stacked on top of this link.
      * @hide
      */
-    public List<LinkProperties> getStackedLinks() {
+    public @NonNull List<LinkProperties> getStackedLinks() {
+        if (mStackedLinks.isEmpty()) {
+            return Collections.EMPTY_LIST;
+        }
         List<LinkProperties> stacked = new ArrayList<LinkProperties>();
         for (LinkProperties link : mStackedLinks.values()) {
-          stacked.add(new LinkProperties(link));
+            stacked.add(new LinkProperties(link));
         }
         return Collections.unmodifiableList(stacked);
     }
diff --git a/core/java/com/android/internal/net/NetworkStatsFactory.java b/core/java/com/android/internal/net/NetworkStatsFactory.java
index e2a2b1eb2a5d..506114bd01f3 100644
--- a/core/java/com/android/internal/net/NetworkStatsFactory.java
+++ b/core/java/com/android/internal/net/NetworkStatsFactory.java
@@ -25,17 +25,20 @@ import static com.android.server.NetworkManagementSocketTagger.kernelToTag;
 import android.net.NetworkStats;
 import android.os.StrictMode;
 import android.os.SystemClock;
+import android.util.ArrayMap;
 
+import com.android.internal.annotations.GuardedBy;
 import com.android.internal.annotations.VisibleForTesting;
 import com.android.internal.util.ArrayUtils;
 import com.android.internal.util.ProcFileReader;
 
+import libcore.io.IoUtils;
+
 import java.io.File;
 import java.io.FileInputStream;
 import java.io.IOException;
 import java.net.ProtocolException;
-
-import libcore.io.IoUtils;
+import java.util.Objects;
 
 /**
  * Creates {@link NetworkStats} instances by parsing various {@code /proc/}
@@ -54,6 +57,19 @@ public class NetworkStatsFactory {
     /** Path to {@code /proc/net/xt_qtaguid/stats}. */
     private final File mStatsXtUid;
 
+    @GuardedBy("sStackedIfaces")
+    private static final ArrayMap<String, String> sStackedIfaces = new ArrayMap<>();
+
+    public static void noteStackedIface(String stackedIface, String baseIface) {
+        synchronized (sStackedIfaces) {
+            if (baseIface != null) {
+                sStackedIfaces.put(stackedIface, baseIface);
+            } else {
+                sStackedIfaces.remove(stackedIface);
+            }
+        }
+    }
+
     public NetworkStatsFactory() {
         this(new File("/proc/"));
     }
@@ -171,8 +187,54 @@ public class NetworkStatsFactory {
     }
 
     public NetworkStats readNetworkStatsDetail(int limitUid, String[] limitIfaces, int limitTag,
-            NetworkStats lastStats)
-            throws IOException {
+            NetworkStats lastStats) throws IOException {
+        final NetworkStats stats = readNetworkStatsDetailInternal(limitUid, limitIfaces, limitTag,
+                lastStats);
+
+        synchronized (sStackedIfaces) {
+            // Sigh, xt_qtaguid ends up double-counting tx traffic going through
+            // clatd interfaces, so we need to subtract it here.
+            final int size = sStackedIfaces.size();
+            for (int i = 0; i < size; i++) {
+                final String stackedIface = sStackedIfaces.keyAt(i);
+                final String baseIface = sStackedIfaces.valueAt(i);
+
+                // Count up the tx traffic and subtract from root UID on the
+                // base interface.
+                NetworkStats.Entry adjust = new NetworkStats.Entry(baseIface, 0, 0, 0, 0L, 0L, 0L,
+                        0L, 0L);
+                NetworkStats.Entry entry = null;
+                for (int j = 0; j < stats.size(); j++) {
+                    entry = stats.getValues(j, entry);
+                    if (Objects.equals(entry.iface, stackedIface)) {
+                        adjust.txBytes -= entry.txBytes;
+                        adjust.txPackets -= entry.txPackets;
+                    }
+                }
+                stats.combineValues(adjust);
+            }
+        }
+
+        // Double sigh, all rx traffic on clat needs to be tweaked to
+        // account for the dropped IPv6 header size post-unwrap.
+        NetworkStats.Entry entry = null;
+        for (int i = 0; i < stats.size(); i++) {
+            entry = stats.getValues(i, entry);
+            if (entry.iface != null && entry.iface.startsWith("clat")) {
+                // Delta between IPv4 header (20b) and IPv6 header (40b)
+                entry.rxBytes = entry.rxPackets * 20;
+                entry.rxPackets = 0;
+                entry.txBytes = 0;
+                entry.txPackets = 0;
+                stats.combineValues(entry);
+            }
+        }
+
+        return stats;
+    }
+
+    private NetworkStats readNetworkStatsDetailInternal(int limitUid, String[] limitIfaces,
+            int limitTag, NetworkStats lastStats) throws IOException {
         if (USE_NATIVE_PARSING) {
             final NetworkStats stats;
             if (lastStats != null) {