diff --git a/core/java/android/net/NetworkStats.java b/core/java/android/net/NetworkStats.java index 292bf8e196..f0dd2629f9 100644 --- a/core/java/android/net/NetworkStats.java +++ b/core/java/android/net/NetworkStats.java @@ -31,6 +31,7 @@ import java.io.CharArrayWriter; import java.io.PrintWriter; import java.util.Arrays; import java.util.HashSet; +import java.util.Map; import java.util.Objects; /** @@ -97,6 +98,11 @@ public class NetworkStats implements Parcelable { /** Denotes a request for stats at the interface and UID level. */ public static final int STATS_PER_UID = 1; + private static final String CLATD_INTERFACE_PREFIX = "v4-"; + // Delta between IPv4 header (20b) and IPv6 header (40b). + // Used for correct stats accounting on clatd interfaces. + private static final int IPV4V6_HEADER_DELTA = 20; + // TODO: move fields to "mVariable" notation /** @@ -758,6 +764,75 @@ public class NetworkStats implements Parcelable { return result; } + /** + * Calculate and apply adjustments to captured statistics for 464xlat traffic counted twice. + * + *

This mutates both base and stacked traffic stats, to account respectively for + * double-counted traffic and IPv4/IPv6 header size difference. + * + *

For 464xlat traffic, xt_qtaguid sees every IPv4 packet twice, once as a native IPv4 + * packet on the stacked interface, and once as translated to an IPv6 packet on the + * base interface. For correct stats accounting on the base interface, every 464xlat + * packet needs to be subtracted from the root UID on the base interface both for tx + * and rx traffic (http://b/12249687, http:/b/33681750). + * + *

This method will behave fine if {@code stackedIfaces} is an non-synchronized but add-only + * {@code ConcurrentHashMap} + * @param baseTraffic Traffic on the base interfaces. Will be mutated. + * @param stackedTraffic Stats with traffic stacked on top of our ifaces. Will also be mutated. + * @param stackedIfaces Mapping ipv6if -> ipv4if interface where traffic is counted on both. + */ + public static void apply464xlatAdjustments(NetworkStats baseTraffic, + NetworkStats stackedTraffic, Map stackedIfaces) { + // Total 464xlat traffic to subtract from uid 0 on all base interfaces. + // stackedIfaces may grow afterwards, but NetworkStats will just be resized automatically. + final NetworkStats adjustments = new NetworkStats(0, stackedIfaces.size()); + + // For recycling + Entry entry = null; + Entry adjust = new NetworkStats.Entry(IFACE_ALL, 0, 0, 0, 0, 0, 0, 0L, 0L, 0L, 0L, 0L); + + for (int i = 0; i < stackedTraffic.size; i++) { + entry = stackedTraffic.getValues(i, entry); + if (entry.iface == null || !entry.iface.startsWith(CLATD_INTERFACE_PREFIX)) { + continue; + } + final String baseIface = stackedIfaces.get(entry.iface); + if (baseIface == null) { + continue; + } + // Subtract any 464lat traffic seen for the root UID on the current base interface. + adjust.iface = baseIface; + adjust.rxBytes = -(entry.rxBytes + entry.rxPackets * IPV4V6_HEADER_DELTA); + adjust.txBytes = -(entry.txBytes + entry.txPackets * IPV4V6_HEADER_DELTA); + adjust.rxPackets = -entry.rxPackets; + adjust.txPackets = -entry.txPackets; + adjustments.combineValues(adjust); + + // For 464xlat traffic, xt_qtaguid only counts the bytes of the native IPv4 packet sent + // on the stacked interface with prefix "v4-" and drops the IPv6 header size after + // unwrapping. To account correctly for on-the-wire traffic, add the 20 additional bytes + // difference for all packets (http://b/12249687, http:/b/33681750). + entry.rxBytes += entry.rxPackets * IPV4V6_HEADER_DELTA; + entry.txBytes += entry.txPackets * IPV4V6_HEADER_DELTA; + stackedTraffic.setValues(i, entry); + } + + baseTraffic.combineAllValues(adjustments); + } + + /** + * Calculate and apply adjustments to captured statistics for 464xlat traffic counted twice. + * + *

This mutates the object this method is called on. Equivalent to calling + * {@link #apply464xlatAdjustments(NetworkStats, NetworkStats, Map)} with {@code this} as + * base and stacked traffic. + * @param stackedIfaces Mapping ipv6if -> ipv4if interface where traffic is counted on both. + */ + public void apply464xlatAdjustments(Map stackedIfaces) { + apply464xlatAdjustments(this, this, stackedIfaces); + } + /** * Return total statistics grouped by {@link #iface}; doesn't mutate the * original structure. diff --git a/core/java/com/android/internal/net/NetworkStatsFactory.java b/core/java/com/android/internal/net/NetworkStatsFactory.java index 0cf5375076..98afebc51b 100644 --- a/core/java/com/android/internal/net/NetworkStatsFactory.java +++ b/core/java/com/android/internal/net/NetworkStatsFactory.java @@ -56,11 +56,6 @@ public class NetworkStatsFactory { private static final boolean USE_NATIVE_PARSING = true; private static final boolean SANITY_CHECK_NATIVE = false; - private static final String CLATD_INTERFACE_PREFIX = "v4-"; - // Delta between IPv4 header (20b) and IPv6 header (40b). - // Used for correct stats accounting on clatd interfaces. - private static final int IPV4V6_HEADER_DELTA = 20; - /** Path to {@code /proc/net/dev}. */ private final File mStatsIfaceDev; /** Path to {@code /proc/net/xt_qtaguid/iface_stat_all}. */ @@ -96,7 +91,7 @@ public class NetworkStatsFactory { * {@link #noteStackedIface(String, String)}, but only interfaces noted before this method * is called are guaranteed to be included. */ - public static String[] augmentWithStackedInterfacesLocked(@Nullable String[] requiredIfaces) { + public static String[] augmentWithStackedInterfaces(@Nullable String[] requiredIfaces) { if (requiredIfaces == NetworkStats.INTERFACES_ALL) { return null; } @@ -118,6 +113,15 @@ public class NetworkStatsFactory { return relatedIfaces.toArray(outArray); } + /** + * Applies 464xlat adjustments with ifaces noted with {@link #noteStackedIface(String, String)}. + * @see NetworkStats#apply464xlatAdjustments(NetworkStats, NetworkStats, Map) + */ + public static void apply464xlatAdjustments(NetworkStats baseTraffic, + NetworkStats stackedTraffic) { + NetworkStats.apply464xlatAdjustments(baseTraffic, stackedTraffic, sStackedIfaces); + } + @VisibleForTesting public static void clearStackedIfaces() { sStackedIfaces.clear(); @@ -289,48 +293,10 @@ public class NetworkStatsFactory { NetworkStats lastStats) throws IOException { final NetworkStats stats = readNetworkStatsDetailInternal(limitUid, limitIfaces, limitTag, lastStats); - // Total 464xlat traffic to subtract from uid 0 on all base interfaces. - // sStackedIfaces may grow afterwards, but NetworkStats will just be resized automatically. - final NetworkStats adjustments = new NetworkStats(0, sStackedIfaces.size()); - NetworkStats.Entry entry = null; // For recycling - - // For 464xlat traffic, xt_qtaguid sees every IPv4 packet twice, once as a native IPv4 - // packet on the stacked interface, and once as translated to an IPv6 packet on the - // base interface. For correct stats accounting on the base interface, every 464xlat - // packet needs to be subtracted from the root UID on the base interface both for tx - // and rx traffic (http://b/12249687, http:/b/33681750). - for (int i = 0; i < stats.size(); i++) { - entry = stats.getValues(i, entry); - if (entry.iface == null || !entry.iface.startsWith(CLATD_INTERFACE_PREFIX)) { - continue; - } - final String baseIface = sStackedIfaces.get(entry.iface); - if (baseIface == null) { - continue; - } - - NetworkStats.Entry adjust = - new NetworkStats.Entry(baseIface, 0, 0, 0, 0, 0, 0, 0L, 0L, 0L, 0L, 0L); - // Subtract any 464lat traffic seen for the root UID on the current base interface. - adjust.rxBytes -= (entry.rxBytes + entry.rxPackets * IPV4V6_HEADER_DELTA); - adjust.txBytes -= (entry.txBytes + entry.txPackets * IPV4V6_HEADER_DELTA); - adjust.rxPackets -= entry.rxPackets; - adjust.txPackets -= entry.txPackets; - adjustments.combineValues(adjust); - - // For 464xlat traffic, xt_qtaguid only counts the bytes of the native IPv4 packet sent - // on the stacked interface with prefix "v4-" and drops the IPv6 header size after - // unwrapping. To account correctly for on-the-wire traffic, add the 20 additional bytes - // difference for all packets (http://b/12249687, http:/b/33681750). - entry.rxBytes = entry.rxPackets * IPV4V6_HEADER_DELTA; - entry.txBytes = entry.txPackets * IPV4V6_HEADER_DELTA; - entry.rxPackets = 0; - entry.txPackets = 0; - stats.combineValues(entry); - } - - stats.combineAllValues(adjustments); + // No locking here: apply464xlatAdjustments behaves fine with an add-only ConcurrentHashMap. + // TODO: remove this and only apply adjustments in NetworkStatsService. + stats.apply464xlatAdjustments(sStackedIfaces); return stats; } diff --git a/services/core/java/com/android/server/net/NetworkStatsService.java b/services/core/java/com/android/server/net/NetworkStatsService.java index 57828ca5dc..4e848f8f36 100644 --- a/services/core/java/com/android/server/net/NetworkStatsService.java +++ b/services/core/java/com/android/server/net/NetworkStatsService.java @@ -148,7 +148,6 @@ import java.time.ZoneOffset; import java.util.Arrays; import java.util.HashSet; import java.util.List; -import java.util.Map; /** * Collect and persist detailed network statistics, and provide this data to @@ -769,7 +768,7 @@ public class NetworkStatsService extends INetworkStatsService.Stub { public NetworkStats getDetailedUidStats(String[] requiredIfaces) { try { final String[] ifacesToQuery = - NetworkStatsFactory.augmentWithStackedInterfacesLocked(requiredIfaces); + NetworkStatsFactory.augmentWithStackedInterfaces(requiredIfaces); return getNetworkStatsUidDetail(ifacesToQuery); } catch (RemoteException e) { Log.wtf(TAG, "Error compiling UID stats", e); @@ -1527,12 +1526,14 @@ public class NetworkStatsService extends INetworkStatsService.Stub { private NetworkStats getNetworkStatsUidDetail(String[] ifaces) throws RemoteException { + // TODO: remove 464xlat adjustments from NetworkStatsFactory and apply all at once here. final NetworkStats uidSnapshot = mNetworkManager.getNetworkStatsUidDetail(UID_ALL, ifaces); // fold tethering stats and operations into uid snapshot final NetworkStats tetherSnapshot = getNetworkStatsTethering(STATS_PER_UID); tetherSnapshot.filter(UID_ALL, ifaces, TAG_ALL); + NetworkStatsFactory.apply464xlatAdjustments(uidSnapshot, tetherSnapshot); uidSnapshot.combineAllValues(tetherSnapshot); final TelephonyManager telephonyManager = (TelephonyManager) mContext.getSystemService( @@ -1542,13 +1543,12 @@ public class NetworkStatsService extends INetworkStatsService.Stub { final NetworkStats vtStats = telephonyManager.getVtDataUsage(STATS_PER_UID); if (vtStats != null) { vtStats.filter(UID_ALL, ifaces, TAG_ALL); + NetworkStatsFactory.apply464xlatAdjustments(uidSnapshot, vtStats); uidSnapshot.combineAllValues(vtStats); } uidSnapshot.combineAllValues(mUidOperations); - // TODO: apply tethering & VC 464xlat adjustments here - return uidSnapshot; }