[MS09] Implement isSameNetwork. (a39756a5) · Commits · e / os / android_frameworks_base

core/java/android/net/ipmemorystore/NetworkAttributes.java

+59 −1

Original line number	Diff line number	Diff line
		@@ -37,27 +37,57 @@ import java.util.StringJoiner;
		public class NetworkAttributes {
		private static final boolean DBG = true;

		// Weight cutoff for grouping. To group, a similarity score is computed with the following
		// algorithm : if both fields are non-null and equals() then add their assigned weight, else if
		// both are null then add a portion of their assigned weight (see NULL_MATCH_WEIGHT),
		// otherwise add nothing.
		// As a guideline, this should be something like 60~75% of the total weights in this class. The
		// design states "in essence a reader should imagine that if two important columns don't match,
		// or one important and several unimportant columns don't match then the two records are
		// considered a different group".
		private static final float TOTAL_WEIGHT_CUTOFF = 520.0f;
		// The portion of the weight that is earned when scoring group-sameness by having both columns
		// being null. This is because some networks rightfully don't have some attributes (e.g. a
		// V6-only network won't have an assigned V4 address) and both being null should count for
		// something, but attributes may also be null just because data is unavailable.
		private static final float NULL_MATCH_WEIGHT = 0.25f;

		// The v4 address that was assigned to this device the last time it joined this network.
		// This typically comes from DHCP but could be something else like static configuration.
		// This does not apply to IPv6.
		// TODO : add a list of v6 prefixes for the v6 case.
		@Nullable
		public final Inet4Address assignedV4Address;
		private static final float WEIGHT_ASSIGNEDV4ADDR = 300.0f;

		// Optionally supplied by the client if it has an opinion on L3 network. For example, this
		// could be a hash of the SSID + security type on WiFi.
		@Nullable
		public final String groupHint;
		private static final float WEIGHT_GROUPHINT = 300.0f;

		// The list of DNS server addresses.
		@Nullable
		public final List<InetAddress> dnsAddresses;
		private static final float WEIGHT_DNSADDRESSES = 200.0f;

		// The mtu on this network.
		@Nullable
		public final Integer mtu;
		private static final float WEIGHT_MTU = 50.0f;

		// The sum of all weights in this class. Tests ensure that this stays equal to the total of
		// all weights.
		/** @hide */
		@VisibleForTesting
		public static final float TOTAL_WEIGHT = WEIGHT_ASSIGNEDV4ADDR
		+ WEIGHT_GROUPHINT
		+ WEIGHT_DNSADDRESSES
		+ WEIGHT_MTU;

		NetworkAttributes(
		/** @hide */
		@VisibleForTesting
		public NetworkAttributes(
		@Nullable final Inet4Address assignedV4Address,
		@Nullable final String groupHint,
		@Nullable final List<InetAddress> dnsAddresses,
		@@ -126,6 +156,34 @@ public class NetworkAttributes {
		return parcelable;
		}

		private float samenessContribution(final float weight,
		@Nullable final Object o1, @Nullable final Object o2) {
		if (null == o1) {
		return (null == o2) ? weight * NULL_MATCH_WEIGHT : 0f;
		}
		return Objects.equals(o1, o2) ? weight : 0f;
		}

		/** @hide */
		public float getNetworkGroupSamenessConfidence(@NonNull final NetworkAttributes o) {
		final float samenessScore =
		samenessContribution(WEIGHT_ASSIGNEDV4ADDR, assignedV4Address, o.assignedV4Address)
		+ samenessContribution(WEIGHT_GROUPHINT, groupHint, o.groupHint)
		+ samenessContribution(WEIGHT_DNSADDRESSES, dnsAddresses, o.dnsAddresses)
		+ samenessContribution(WEIGHT_MTU, mtu, o.mtu);
		// The minimum is 0, the max is TOTAL_WEIGHT and should be represented by 1.0, and
		// TOTAL_WEIGHT_CUTOFF should represent 0.5, but there is no requirement that
		// TOTAL_WEIGHT_CUTOFF would be half of TOTAL_WEIGHT (indeed, it should not be).
		// So scale scores under the cutoff between 0 and 0.5, and the scores over the cutoff
		// between 0.5 and 1.0.
		if (samenessScore < TOTAL_WEIGHT_CUTOFF) {
		return samenessScore / (TOTAL_WEIGHT_CUTOFF * 2);
		} else {
		return (samenessScore - TOTAL_WEIGHT_CUTOFF) / (TOTAL_WEIGHT - TOTAL_WEIGHT_CUTOFF) / 2
		+ 0.5f;
		}
		}

		/** @hide */
		public static class Builder {
		@Nullable

core/java/android/net/ipmemorystore/SameL3NetworkResponse.java

+2 −1

Original line number	Diff line number	Diff line
		@@ -91,7 +91,8 @@ public class SameL3NetworkResponse {
		return confidence > 0.5 ? NETWORK_SAME : NETWORK_DIFFERENT;
		}

		SameL3NetworkResponse(@NonNull final String l2Key1, @NonNull final String l2Key2,
		/** @hide */
		public SameL3NetworkResponse(@NonNull final String l2Key1, @NonNull final String l2Key2,
		final float confidence) {
		this.l2Key1 = l2Key1;
		this.l2Key2 = l2Key2;

services/ipmemorystore/java/com/android/server/net/ipmemorystore/IpMemoryStoreService.java

+35 −3

Original line number	Diff line number	Diff line
		@@ -37,6 +37,7 @@ import android.net.ipmemorystore.IOnSameNetworkResponseListener;
		import android.net.ipmemorystore.IOnStatusListener;
		import android.net.ipmemorystore.NetworkAttributes;
		import android.net.ipmemorystore.NetworkAttributesParcelable;
		import android.net.ipmemorystore.SameL3NetworkResponse;
		import android.net.ipmemorystore.Status;
		import android.net.ipmemorystore.StatusParcelable;
		import android.net.ipmemorystore.Utils;
		@@ -264,9 +265,40 @@ public class IpMemoryStoreService extends IIpMemoryStore.Stub {
		* Through the listener, a SameL3NetworkResponse containing the answer and confidence.
		*/
		@Override
		public void isSameNetwork(@NonNull final String l2Key1, @NonNull final String l2Key2,
		@NonNull final IOnSameNetworkResponseListener listener) {
		// TODO : implement this.
		public void isSameNetwork(@Nullable final String l2Key1, @Nullable final String l2Key2,
		@Nullable final IOnSameNetworkResponseListener listener) {
		if (null == listener) return;
		mExecutor.execute(() -> {
		try {
		if (null == l2Key1 \|\| null == l2Key2) {
		listener.onSameNetworkResponse(makeStatus(ERROR_ILLEGAL_ARGUMENT), null);
		return;
		}
		if (null == mDb) {
		listener.onSameNetworkResponse(makeStatus(ERROR_ILLEGAL_ARGUMENT), null);
		return;
		}
		try {
		final NetworkAttributes attr1 =
		IpMemoryStoreDatabase.retrieveNetworkAttributes(mDb, l2Key1);
		final NetworkAttributes attr2 =
		IpMemoryStoreDatabase.retrieveNetworkAttributes(mDb, l2Key2);
		if (null == attr1 \|\| null == attr2) {
		listener.onSameNetworkResponse(makeStatus(SUCCESS),
		new SameL3NetworkResponse(l2Key1, l2Key2,
		-1f /* never connected */).toParcelable());
		return;
		}
		final float confidence = attr1.getNetworkGroupSamenessConfidence(attr2);
		listener.onSameNetworkResponse(makeStatus(SUCCESS),
		new SameL3NetworkResponse(l2Key1, l2Key2, confidence).toParcelable());
		} catch (Exception e) {
		listener.onSameNetworkResponse(makeStatus(ERROR_GENERIC), null);
		}
		} catch (final RemoteException e) {
		// Client at the other end died
		}
		});
		}

		/**

tests/net/java/com/android/server/net/ipmemorystore/IpMemoryStoreServiceTest.java

+88 −12

Original line number	Diff line number	Diff line
		@@ -28,9 +28,12 @@ import android.content.Context;
		import android.net.ipmemorystore.Blob;
		import android.net.ipmemorystore.IOnBlobRetrievedListener;
		import android.net.ipmemorystore.IOnNetworkAttributesRetrieved;
		import android.net.ipmemorystore.IOnSameNetworkResponseListener;
		import android.net.ipmemorystore.IOnStatusListener;
		import android.net.ipmemorystore.NetworkAttributes;
		import android.net.ipmemorystore.NetworkAttributesParcelable;
		import android.net.ipmemorystore.SameL3NetworkResponse;
		import android.net.ipmemorystore.SameL3NetworkResponseParcelable;
		import android.net.ipmemorystore.Status;
		import android.net.ipmemorystore.StatusParcelable;
		import android.os.IBinder;
		@@ -144,6 +147,28 @@ public class IpMemoryStoreServiceTest {
		};
		}

		/** Helper method to make an IOnSameNetworkResponseListener */
		private interface OnSameNetworkResponseListener {
		void onSameNetworkResponse(Status status, SameL3NetworkResponse answer);
		}
		private IOnSameNetworkResponseListener onSameResponse(
		final OnSameNetworkResponseListener functor) {
		return new IOnSameNetworkResponseListener() {
		@Override
		public void onSameNetworkResponse(final StatusParcelable status,
		final SameL3NetworkResponseParcelable sameL3Network)
		throws RemoteException {
		functor.onSameNetworkResponse(new Status(status),
		null == sameL3Network ? null : new SameL3NetworkResponse(sameL3Network));
		}

		@Override
		public IBinder asBinder() {
		return null;
		}
		};
		}

		// Helper method to factorize some boilerplate
		private void doLatched(final String timeoutMessage, final Consumer<CountDownLatch> functor) {
		final CountDownLatch latch = new CountDownLatch(1);
		@@ -155,6 +180,19 @@ public class IpMemoryStoreServiceTest {
		}
		}

		// Helper methods to factorize more boilerplate
		private void storeAttributes(final String l2Key, final NetworkAttributes na) {
		storeAttributes("Did not complete storing attributes", l2Key, na);
		}
		private void storeAttributes(final String timeoutMessage, final String l2Key,
		final NetworkAttributes na) {
		doLatched(timeoutMessage, latch -> mService.storeNetworkAttributes(l2Key, na.toParcelable(),
		onStatus(status -> {
		assertTrue("Store not successful : " + status.resultCode, status.isSuccess());
		latch.countDown();
		})));
		}

		@Test
		public void testNetworkAttributes() {
		final NetworkAttributes.Builder na = new NetworkAttributes.Builder();
		@@ -166,13 +204,7 @@ public class IpMemoryStoreServiceTest {
		na.setMtu(219);
		final String l2Key = UUID.randomUUID().toString();
		NetworkAttributes attributes = na.build();
		doLatched("Did not complete storing attributes", latch ->
		mService.storeNetworkAttributes(l2Key, attributes.toParcelable(),
		onStatus(status -> {
		assertTrue("Store status not successful : " + status.resultCode,
		status.isSuccess());
		latch.countDown();
		})));
		storeAttributes(l2Key, attributes);

		doLatched("Did not complete retrieving attributes", latch ->
		mService.retrieveNetworkAttributes(l2Key, onNetworkAttributesRetrieved(
		@@ -190,9 +222,7 @@ public class IpMemoryStoreServiceTest {
		new InetAddress[] {Inet6Address.getByName("0A1C:2E40:480A::1CA6")}));
		} catch (UnknownHostException e) { /* Still can't happen */ }
		final NetworkAttributes attributes2 = na2.build();
		doLatched("Did not complete storing attributes 2", latch ->
		mService.storeNetworkAttributes(l2Key, attributes2.toParcelable(),
		onStatus(status -> latch.countDown())));
		storeAttributes("Did not complete storing attributes 2", l2Key, attributes2);

		doLatched("Did not complete retrieving attributes 2", latch ->
		mService.retrieveNetworkAttributes(l2Key, onNetworkAttributesRetrieved(
		@@ -306,8 +336,54 @@ public class IpMemoryStoreServiceTest {
		// TODO : implement this
		}

		private void assertNetworksSameness(final String key1, final String key2, final int sameness) {
		doLatched("Did not finish evaluating sameness", latch ->
		mService.isSameNetwork(key1, key2, onSameResponse((status, answer) -> {
		assertTrue("Retrieve network sameness not successful : " + status.resultCode,
		status.isSuccess());
		assertEquals(sameness, answer.getNetworkSameness());
		})));
		}

		@Test
		public void testIsSameNetwork() {
		// TODO : implement this
		public void testIsSameNetwork() throws UnknownHostException {
		final NetworkAttributes.Builder na = new NetworkAttributes.Builder();
		na.setAssignedV4Address((Inet4Address) Inet4Address.getByAddress(new byte[]{1, 2, 3, 4}));
		na.setGroupHint("hint1");
		na.setMtu(219);
		na.setDnsAddresses(Arrays.asList(Inet6Address.getByName("0A1C:2E40:480A::1CA6")));

		final String[] keys = new String[4];
		for (int i = 0; i < keys.length; ++i) {
		keys[i] = UUID.randomUUID().toString();
		}
		storeAttributes(keys[0], na.build());
		// 0 and 1 have identical attributes
		storeAttributes(keys[1], na.build());

		// Hopefully only the MTU being different still means it's the same network
		na.setMtu(200);
		storeAttributes(keys[2], na.build());

		// Hopefully different MTU, assigned V4 address and grouphint make a different network,
		// even with identical DNS addresses
		na.setAssignedV4Address(null);
		na.setGroupHint("hint2");
		storeAttributes(keys[3], na.build());

		assertNetworksSameness(keys[0], keys[1], SameL3NetworkResponse.NETWORK_SAME);
		assertNetworksSameness(keys[0], keys[2], SameL3NetworkResponse.NETWORK_SAME);
		assertNetworksSameness(keys[1], keys[2], SameL3NetworkResponse.NETWORK_SAME);
		assertNetworksSameness(keys[0], keys[3], SameL3NetworkResponse.NETWORK_DIFFERENT);
		assertNetworksSameness(keys[0], UUID.randomUUID().toString(),
		SameL3NetworkResponse.NETWORK_NEVER_CONNECTED);

		doLatched("Did not finish evaluating sameness", latch ->
		mService.isSameNetwork(null, null, onSameResponse((status, answer) -> {
		assertFalse("Retrieve network sameness suspiciously successful : "
		+ status.resultCode, status.isSuccess());
		assertEquals(Status.ERROR_ILLEGAL_ARGUMENT, status.resultCode);
		assertNull(answer);
		})));
		}
		}

tests/net/java/com/android/server/net/ipmemorystore/NetworkAttributesTest.java

0 → 100644

+65 −0

Original line number	Diff line number	Diff line
		/*
		* Copyright (C) 2019 The Android Open Source Project
		*
		* Licensed under the Apache License, Version 2.0 (the "License");
		* you may not use this file except in compliance with the License.
		* You may obtain a copy of the License at
		*
		* http://www.apache.org/licenses/LICENSE-2.0
		*
		* Unless required by applicable law or agreed to in writing, software
		* distributed under the License is distributed on an "AS IS" BASIS,
		* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
		* See the License for the specific language governing permissions and
		* limitations under the License.
		*/

		package com.android.server.net.ipmemorystore;

		import static org.junit.Assert.assertEquals;

		import android.net.ipmemorystore.NetworkAttributes;
		import android.support.test.filters.SmallTest;
		import android.support.test.runner.AndroidJUnit4;

		import org.junit.Test;
		import org.junit.runner.RunWith;

		import java.lang.reflect.Field;
		import java.net.Inet4Address;
		import java.net.UnknownHostException;
		import java.util.Arrays;

		/** Unit tests for {@link NetworkAttributes}. */
		@SmallTest
		@RunWith(AndroidJUnit4.class)
		public class NetworkAttributesTest {
		private static final String WEIGHT_FIELD_NAME_PREFIX = "WEIGHT_";
		private static final float EPSILON = 0.0001f;

		// This is running two tests to make sure the total weight is the sum of all weights. To be
		// sure this is not fireproof, but you'd kind of need to do it on purpose to pass.
		@Test
		public void testTotalWeight() throws IllegalAccessException, UnknownHostException {
		// Make sure that TOTAL_WEIGHT is equal to the sum of the fields starting with WEIGHT_
		float sum = 0f;
		final Field[] fieldList = NetworkAttributes.class.getDeclaredFields();
		for (final Field field : fieldList) {
		if (!field.getName().startsWith(WEIGHT_FIELD_NAME_PREFIX)) continue;
		field.setAccessible(true);
		sum += (float) field.get(null);
		}
		assertEquals(sum, NetworkAttributes.TOTAL_WEIGHT, EPSILON);

		// Use directly the constructor with all attributes, and make sure that when compared
		// to itself the score is a clean 1.0f.
		final NetworkAttributes na =
		new NetworkAttributes(
		(Inet4Address) Inet4Address.getByAddress(new byte[] {1, 2, 3, 4}),
		"some hint",
		Arrays.asList(Inet4Address.getByAddress(new byte[] {5, 6, 7, 8}),
		Inet4Address.getByAddress(new byte[] {9, 0, 1, 2})),
		98);
		assertEquals(1.0f, na.getNetworkGroupSamenessConfidence(na), EPSILON);
		}
		}