NetworkStats to support VPN accounting. (21377c3a) · Commits · e / os / android_frameworks_base

core/java/android/net/NetworkStats.java

+160 −0

Original line number	Diff line number	Diff line
		@@ -19,6 +19,7 @@ package android.net;
		import android.os.Parcel;
		import android.os.Parcelable;
		import android.os.SystemClock;
		import android.util.Slog;
		import android.util.SparseBooleanArray;

		import com.android.internal.annotations.VisibleForTesting;
		@@ -42,6 +43,7 @@ import java.util.Objects;
		* @hide
		*/
		public class NetworkStats implements Parcelable {
		private static final String TAG = "NetworkStats";
		/** {@link #iface} value when interface details unavailable. */
		public static final String IFACE_ALL = null;
		/** {@link #uid} value when UID details unavailable. */
		@@ -783,4 +785,162 @@ public class NetworkStats implements Parcelable {
		public void foundNonMonotonic(
		NetworkStats left, int leftIndex, NetworkStats right, int rightIndex, C cookie);
		}

		/**
		* VPN accounting. Move some VPN's underlying traffic to other UIDs that use tun0 iface.
		*
		* This method should only be called on delta NetworkStats. Do not call this method on a
		* snapshot {@link NetworkStats} object because the tunUid and/or the underlyingIface may
		* change over time.
		*
		* This method performs adjustments for one active VPN package and one VPN iface at a time.
		*
		* It is possible for the VPN software to use multiple underlying networks. This method
		* only migrates traffic for the primary underlying network.
		*
		* @param tunUid uid of the VPN application
		* @param tunIface iface of the vpn tunnel
		* @param underlyingIface the primary underlying network iface used by the VPN application
		* @return true if it successfully adjusts the accounting for VPN, false otherwise
		*/
		public boolean migrateTun(int tunUid, String tunIface, String underlyingIface) {
		Entry tunIfaceTotal = new Entry();
		Entry underlyingIfaceTotal = new Entry();

		tunAdjustmentInit(tunUid, tunIface, underlyingIface, tunIfaceTotal, underlyingIfaceTotal);

		// If tunIface < underlyingIface, it leaves the overhead traffic in the VPN app.
		// If tunIface > underlyingIface, the VPN app doesn't get credit for data compression.
		// Negative stats should be avoided.
		Entry pool = tunGetPool(tunIfaceTotal, underlyingIfaceTotal);
		if (pool.isEmpty()) {
		return true;
		}
		Entry moved = addTrafficToApplications(tunIface, underlyingIface, tunIfaceTotal, pool);
		deductTrafficFromVpnApp(tunUid, underlyingIface, moved);

		if (!moved.isEmpty()) {
		Slog.wtf(TAG, "Failed to deduct underlying network traffic from VPN package. Moved="
		+ moved);
		return false;
		}
		return true;
		}

		/**
		* Initializes the data used by the migrateTun() method.
		*
		* This is the first pass iteration which does the following work:
		* (1) Adds up all the traffic through tun0.
		* (2) Adds up all the traffic through the tunUid's underlyingIface
		* (both foreground and background).
		*/
		private void tunAdjustmentInit(int tunUid, String tunIface, String underlyingIface,
		Entry tunIfaceTotal, Entry underlyingIfaceTotal) {
		Entry recycle = new Entry();
		for (int i = 0; i < size; i++) {
		getValues(i, recycle);
		if (recycle.uid == UID_ALL) {
		throw new IllegalStateException(
		"Cannot adjust VPN accounting on an iface aggregated NetworkStats.");
		}

		if (recycle.uid == tunUid && recycle.tag == TAG_NONE
		&& Objects.equals(underlyingIface, recycle.iface)) {
		underlyingIfaceTotal.add(recycle);
		}

		if (recycle.tag == TAG_NONE && Objects.equals(tunIface, recycle.iface)) {
		// Add up all tunIface traffic.
		tunIfaceTotal.add(recycle);
		}
		}
		}

		private static Entry tunGetPool(Entry tunIfaceTotal, Entry underlyingIfaceTotal) {
		Entry pool = new Entry();
		pool.rxBytes = Math.min(tunIfaceTotal.rxBytes, underlyingIfaceTotal.rxBytes);
		pool.rxPackets = Math.min(tunIfaceTotal.rxPackets, underlyingIfaceTotal.rxPackets);
		pool.txBytes = Math.min(tunIfaceTotal.txBytes, underlyingIfaceTotal.txBytes);
		pool.txPackets = Math.min(tunIfaceTotal.txPackets, underlyingIfaceTotal.txPackets);
		pool.operations = Math.min(tunIfaceTotal.operations, underlyingIfaceTotal.operations);
		return pool;
		}

		private Entry addTrafficToApplications(String tunIface, String underlyingIface,
		Entry tunIfaceTotal, Entry pool) {
		Entry moved = new Entry();
		Entry tmpEntry = new Entry();
		tmpEntry.iface = underlyingIface;
		for (int i = 0; i < size; i++) {
		if (Objects.equals(iface[i], tunIface)) {
		if (tunIfaceTotal.rxBytes > 0) {
		tmpEntry.rxBytes = pool.rxBytes * rxBytes[i] / tunIfaceTotal.rxBytes;
		} else {
		tmpEntry.rxBytes = 0;
		}
		if (tunIfaceTotal.rxPackets > 0) {
		tmpEntry.rxPackets = pool.rxPackets * rxPackets[i] / tunIfaceTotal.rxPackets;
		} else {
		tmpEntry.rxPackets = 0;
		}
		if (tunIfaceTotal.txBytes > 0) {
		tmpEntry.txBytes = pool.txBytes * txBytes[i] / tunIfaceTotal.txBytes;
		} else {
		tmpEntry.txBytes = 0;
		}
		if (tunIfaceTotal.txPackets > 0) {
		tmpEntry.txPackets = pool.txPackets * txPackets[i] / tunIfaceTotal.txPackets;
		} else {
		tmpEntry.txPackets = 0;
		}
		if (tunIfaceTotal.operations > 0) {
		tmpEntry.operations =
		pool.operations * operations[i] / tunIfaceTotal.operations;
		} else {
		tmpEntry.operations = 0;
		}
		tmpEntry.uid = uid[i];
		tmpEntry.tag = tag[i];
		tmpEntry.set = set[i];
		combineValues(tmpEntry);
		if (tag[i] == TAG_NONE) {
		moved.add(tmpEntry);
		}
		}
		}
		return moved;
		}

		private void deductTrafficFromVpnApp(int tunUid, String underlyingIface, Entry moved) {
		// Caveat: if the vpn software uses tag, the total tagged traffic may be greater than
		// the TAG_NONE traffic.
		int idxVpnBackground = findIndex(underlyingIface, tunUid, SET_DEFAULT, TAG_NONE);
		if (idxVpnBackground != -1) {
		tunSubtract(idxVpnBackground, this, moved);
		}

		int idxVpnForeground = findIndex(underlyingIface, tunUid, SET_FOREGROUND, TAG_NONE);
		if (idxVpnForeground != -1) {
		tunSubtract(idxVpnForeground, this, moved);
		}
		}

		private static void tunSubtract(int i, NetworkStats left, Entry right) {
		long rxBytes = Math.min(left.rxBytes[i], right.rxBytes);
		left.rxBytes[i] -= rxBytes;
		right.rxBytes -= rxBytes;

		long rxPackets = Math.min(left.rxPackets[i], right.rxPackets);
		left.rxPackets[i] -= rxPackets;
		right.rxPackets -= rxPackets;

		long txBytes = Math.min(left.txBytes[i], right.txBytes);
		left.txBytes[i] -= txBytes;
		right.txBytes -= txBytes;

		long txPackets = Math.min(left.txPackets[i], right.txPackets);
		left.txPackets[i] -= txPackets;
		right.txPackets -= txPackets;
		}
		}

core/tests/coretests/src/android/net/NetworkStatsTest.java

+67 −0

Original line number	Diff line number	Diff line
		@@ -320,6 +320,73 @@ public class NetworkStatsTest extends TestCase {
		red.combineAllValues(blue);
		}

		public void testMigrateTun() throws Exception {
		final int tunUid = 10030;
		final String tunIface = "tun0";
		final String underlyingIface = "wlan0";
		final int testTag1 = 8888;
		NetworkStats delta = new NetworkStats(TEST_START, 17)
		.addValues(tunIface, 10100, SET_DEFAULT, TAG_NONE, 39605L, 46L, 12259L, 55L, 0L)
		.addValues(tunIface, 10100, SET_FOREGROUND, TAG_NONE, 0L, 0L, 0L, 0L, 0L)
		.addValues(tunIface, 10120, SET_DEFAULT, TAG_NONE, 72667L, 197L, 43909L, 241L, 0L)
		.addValues(tunIface, 10120, SET_FOREGROUND, TAG_NONE, 9297L, 17L, 4128L, 21L, 0L)
		// VPN package also uses some traffic through unprotected network.
		.addValues(tunIface, tunUid, SET_DEFAULT, TAG_NONE, 4983L, 10L, 1801L, 12L, 0L)
		.addValues(tunIface, tunUid, SET_FOREGROUND, TAG_NONE, 0L, 0L, 0L, 0L, 0L)
		// Tag entries
		.addValues(tunIface, 10120, SET_DEFAULT, testTag1, 21691L, 41L, 13820L, 51L, 0L)
		.addValues(tunIface, 10120, SET_FOREGROUND, testTag1, 1281L, 2L, 665L, 2L, 0L)
		// Irrelevant entries
		.addValues(TEST_IFACE, 10100, SET_DEFAULT, TAG_NONE, 1685L, 5L, 2070L, 6L, 0L)
		// Underlying Iface entries
		.addValues(underlyingIface, 10100, SET_DEFAULT, TAG_NONE, 5178L, 8L, 2139L, 11L, 0L)
		.addValues(underlyingIface, 10100, SET_FOREGROUND, TAG_NONE, 0L, 0L, 0L, 0L, 0L)
		.addValues(underlyingIface, tunUid, SET_DEFAULT, TAG_NONE, 149873L, 287L,
		59217L /* smaller than sum(tun0) /, 299L / smaller than sum(tun0) */, 0L)
		.addValues(underlyingIface, tunUid, SET_FOREGROUND, TAG_NONE, 0L, 0L, 0L, 0L, 0L);

		assertTrue(delta.migrateTun(tunUid, tunIface, underlyingIface));
		assertEquals(17, delta.size());

		// tunIface and TEST_IFACE entries are not changed.
		assertValues(delta, 0, tunIface, 10100, SET_DEFAULT, TAG_NONE,
		39605L, 46L, 12259L, 55L, 0L);
		assertValues(delta, 1, tunIface, 10100, SET_FOREGROUND, TAG_NONE, 0L, 0L, 0L, 0L, 0L);
		assertValues(delta, 2, tunIface, 10120, SET_DEFAULT, TAG_NONE,
		72667L, 197L, 43909L, 241L, 0L);
		assertValues(delta, 3, tunIface, 10120, SET_FOREGROUND, TAG_NONE,
		9297L, 17L, 4128L, 21L, 0L);
		assertValues(delta, 4, tunIface, tunUid, SET_DEFAULT, TAG_NONE,
		4983L, 10L, 1801L, 12L, 0L);
		assertValues(delta, 5, tunIface, tunUid, SET_FOREGROUND, TAG_NONE, 0L, 0L, 0L, 0L, 0L);
		assertValues(delta, 6, tunIface, 10120, SET_DEFAULT, testTag1,
		21691L, 41L, 13820L, 51L, 0L);
		assertValues(delta, 7, tunIface, 10120, SET_FOREGROUND, testTag1, 1281L, 2L, 665L, 2L, 0L);
		assertValues(delta, 8, TEST_IFACE, 10100, SET_DEFAULT, TAG_NONE, 1685L, 5L, 2070L, 6L, 0L);

		// Existing underlying Iface entries are updated
		assertValues(delta, 9, underlyingIface, 10100, SET_DEFAULT, TAG_NONE,
		44783L, 54L, 13829L, 60L, 0L);
		assertValues(delta, 10, underlyingIface, 10100, SET_FOREGROUND, TAG_NONE,
		0L, 0L, 0L, 0L, 0L);

		// VPN underlying Iface entries are updated
		assertValues(delta, 11, underlyingIface, tunUid, SET_DEFAULT, TAG_NONE,
		28304L, 27L, 1719L, 12L, 0L);
		assertValues(delta, 12, underlyingIface, tunUid, SET_FOREGROUND, TAG_NONE,
		0L, 0L, 0L, 0L, 0L);

		// New entries are added for new application's underlying Iface traffic
		assertValues(delta, 13, underlyingIface, 10120, SET_DEFAULT, TAG_NONE,
		72667L, 197L, 41872l, 219L, 0L);
		assertValues(delta, 14, underlyingIface, 10120, SET_FOREGROUND, TAG_NONE,
		9297L, 17L, 3936, 19L, 0L);
		assertValues(delta, 15, underlyingIface, 10120, SET_DEFAULT, testTag1,
		21691L, 41L, 13179L, 46L, 0L);
		assertValues(delta, 16, underlyingIface, 10120, SET_FOREGROUND, testTag1,
		1281L, 2L, 634L, 1L, 0L);
		}

		private static void assertValues(NetworkStats stats, int index, String iface, int uid, int set,
		int tag, long rxBytes, long rxPackets, long txBytes, long txPackets, long operations) {
		final NetworkStats.Entry entry = stats.getValues(index, null);