[MS09] Implement isSameNetwork.
Test: Old tests pass, new tests pass too.
Bug: 113554482
Change-Id: I420471853f3fab7725cba7ae500cebdce1912e43
diff --git a/core/java/android/net/ipmemorystore/NetworkAttributes.java b/core/java/android/net/ipmemorystore/NetworkAttributes.java
index b932d21..5397b57 100644
--- a/core/java/android/net/ipmemorystore/NetworkAttributes.java
+++ b/core/java/android/net/ipmemorystore/NetworkAttributes.java
@@ -37,27 +37,57 @@
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;
- NetworkAttributes(
+ // 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;
+
+ /** @hide */
+ @VisibleForTesting
+ public NetworkAttributes(
@Nullable final Inet4Address assignedV4Address,
@Nullable final String groupHint,
@Nullable final List<InetAddress> dnsAddresses,
@@ -126,6 +156,34 @@
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
diff --git a/core/java/android/net/ipmemorystore/SameL3NetworkResponse.java b/core/java/android/net/ipmemorystore/SameL3NetworkResponse.java
index d040dcc..291aca8 100644
--- a/core/java/android/net/ipmemorystore/SameL3NetworkResponse.java
+++ b/core/java/android/net/ipmemorystore/SameL3NetworkResponse.java
@@ -91,7 +91,8 @@
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;
diff --git a/services/ipmemorystore/java/com/android/server/net/ipmemorystore/IpMemoryStoreService.java b/services/ipmemorystore/java/com/android/server/net/ipmemorystore/IpMemoryStoreService.java
index 444b299..c4d1657 100644
--- a/services/ipmemorystore/java/com/android/server/net/ipmemorystore/IpMemoryStoreService.java
+++ b/services/ipmemorystore/java/com/android/server/net/ipmemorystore/IpMemoryStoreService.java
@@ -37,6 +37,7 @@
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 @@
* 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
+ }
+ });
}
/**
diff --git a/tests/net/java/com/android/server/net/ipmemorystore/IpMemoryStoreServiceTest.java b/tests/net/java/com/android/server/net/ipmemorystore/IpMemoryStoreServiceTest.java
index 94bcd28..c58941a 100644
--- a/tests/net/java/com/android/server/net/ipmemorystore/IpMemoryStoreServiceTest.java
+++ b/tests/net/java/com/android/server/net/ipmemorystore/IpMemoryStoreServiceTest.java
@@ -28,9 +28,12 @@
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 @@
};
}
+ /** 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 @@
}
}
+ // 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 @@
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 @@
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 @@
// 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);
+ })));
}
}
diff --git a/tests/net/java/com/android/server/net/ipmemorystore/NetworkAttributesTest.java b/tests/net/java/com/android/server/net/ipmemorystore/NetworkAttributesTest.java
new file mode 100644
index 0000000..fe19eee
--- /dev/null
+++ b/tests/net/java/com/android/server/net/ipmemorystore/NetworkAttributesTest.java
@@ -0,0 +1,65 @@
+/*
+ * 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);
+ }
+}