Import a few android.net unit tests into frameworks-net

Bug: 62918393
Test: runtest frameworks-net
Change-Id: I3c7c60bcfeffec5c5ec287810312349237a2868a
diff --git a/tests/net/java/android/net/LinkPropertiesTest.java b/tests/net/java/android/net/LinkPropertiesTest.java
new file mode 100644
index 0000000..52da79a
--- /dev/null
+++ b/tests/net/java/android/net/LinkPropertiesTest.java
@@ -0,0 +1,781 @@
+/*
+ * Copyright (C) 2010 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 android.net;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
+
+import android.net.IpPrefix;
+import android.net.LinkAddress;
+import android.net.LinkProperties;
+import android.net.LinkProperties.CompareResult;
+import android.net.LinkProperties.ProvisioningChange;
+import android.net.RouteInfo;
+import android.support.test.filters.SmallTest;
+import android.support.test.runner.AndroidJUnit4;
+import android.system.OsConstants;
+import android.util.ArraySet;
+
+import java.net.InetAddress;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.List;
+import java.util.Set;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+@RunWith(AndroidJUnit4.class)
+@SmallTest
+public class LinkPropertiesTest {
+    private static InetAddress ADDRV4 = NetworkUtils.numericToInetAddress("75.208.6.1");
+    private static InetAddress ADDRV6 = NetworkUtils.numericToInetAddress(
+            "2001:0db8:85a3:0000:0000:8a2e:0370:7334");
+    private static InetAddress DNS1 = NetworkUtils.numericToInetAddress("75.208.7.1");
+    private static InetAddress DNS2 = NetworkUtils.numericToInetAddress("69.78.7.1");
+    private static InetAddress DNS6 = NetworkUtils.numericToInetAddress("2001:4860:4860::8888");
+    private static InetAddress GATEWAY1 = NetworkUtils.numericToInetAddress("75.208.8.1");
+    private static InetAddress GATEWAY2 = NetworkUtils.numericToInetAddress("69.78.8.1");
+    private static InetAddress GATEWAY61 = NetworkUtils.numericToInetAddress("fe80::6:0000:613");
+    private static InetAddress GATEWAY62 = NetworkUtils.numericToInetAddress("fe80::6:2222");
+    private static String NAME = "qmi0";
+    private static int MTU = 1500;
+
+    private static LinkAddress LINKADDRV4 = new LinkAddress(ADDRV4, 32);
+    private static LinkAddress LINKADDRV6 = new LinkAddress(ADDRV6, 128);
+    private static LinkAddress LINKADDRV6LINKLOCAL = new LinkAddress("fe80::1/64");
+
+    // TODO: replace all calls to NetworkUtils.numericToInetAddress with calls to this method.
+    private InetAddress Address(String addrString) {
+        return NetworkUtils.numericToInetAddress(addrString);
+    }
+
+    public void assertLinkPropertiesEqual(LinkProperties source, LinkProperties target) {
+        // Check implementation of equals(), element by element.
+        assertTrue(source.isIdenticalInterfaceName(target));
+        assertTrue(target.isIdenticalInterfaceName(source));
+
+        assertTrue(source.isIdenticalAddresses(target));
+        assertTrue(target.isIdenticalAddresses(source));
+
+        assertTrue(source.isIdenticalDnses(target));
+        assertTrue(target.isIdenticalDnses(source));
+
+        assertTrue(source.isIdenticalRoutes(target));
+        assertTrue(target.isIdenticalRoutes(source));
+
+        assertTrue(source.isIdenticalHttpProxy(target));
+        assertTrue(target.isIdenticalHttpProxy(source));
+
+        assertTrue(source.isIdenticalStackedLinks(target));
+        assertTrue(target.isIdenticalStackedLinks(source));
+
+        assertTrue(source.isIdenticalMtu(target));
+        assertTrue(target.isIdenticalMtu(source));
+
+        // Check result of equals().
+        assertTrue(source.equals(target));
+        assertTrue(target.equals(source));
+
+        // Check hashCode.
+        assertEquals(source.hashCode(), target.hashCode());
+    }
+
+    @Test
+    public void testEqualsNull() {
+        LinkProperties source = new LinkProperties();
+        LinkProperties target = new LinkProperties();
+
+        assertFalse(source == target);
+        assertLinkPropertiesEqual(source, target);
+    }
+
+    @Test
+    public void testEqualsSameOrder() throws Exception {
+        LinkProperties source = new LinkProperties();
+        source.setInterfaceName(NAME);
+        // set 2 link addresses
+        source.addLinkAddress(LINKADDRV4);
+        source.addLinkAddress(LINKADDRV6);
+        // set 2 dnses
+        source.addDnsServer(DNS1);
+        source.addDnsServer(DNS2);
+        // set 2 gateways
+        source.addRoute(new RouteInfo(GATEWAY1));
+        source.addRoute(new RouteInfo(GATEWAY2));
+        source.setMtu(MTU);
+
+        LinkProperties target = new LinkProperties();
+
+        // All fields are same
+        target.setInterfaceName(NAME);
+        target.addLinkAddress(LINKADDRV4);
+        target.addLinkAddress(LINKADDRV6);
+        target.addDnsServer(DNS1);
+        target.addDnsServer(DNS2);
+        target.addRoute(new RouteInfo(GATEWAY1));
+        target.addRoute(new RouteInfo(GATEWAY2));
+        target.setMtu(MTU);
+
+        assertLinkPropertiesEqual(source, target);
+
+        target.clear();
+        // change Interface Name
+        target.setInterfaceName("qmi1");
+        target.addLinkAddress(LINKADDRV4);
+        target.addLinkAddress(LINKADDRV6);
+        target.addDnsServer(DNS1);
+        target.addDnsServer(DNS2);
+        target.addRoute(new RouteInfo(GATEWAY1));
+        target.addRoute(new RouteInfo(GATEWAY2));
+        target.setMtu(MTU);
+        assertFalse(source.equals(target));
+
+        target.clear();
+        target.setInterfaceName(NAME);
+        // change link addresses
+        target.addLinkAddress(new LinkAddress(
+                NetworkUtils.numericToInetAddress("75.208.6.2"), 32));
+        target.addLinkAddress(LINKADDRV6);
+        target.addDnsServer(DNS1);
+        target.addDnsServer(DNS2);
+        target.addRoute(new RouteInfo(GATEWAY1));
+        target.addRoute(new RouteInfo(GATEWAY2));
+        target.setMtu(MTU);
+        assertFalse(source.equals(target));
+
+        target.clear();
+        target.setInterfaceName(NAME);
+        target.addLinkAddress(LINKADDRV4);
+        target.addLinkAddress(LINKADDRV6);
+        // change dnses
+        target.addDnsServer(NetworkUtils.numericToInetAddress("75.208.7.2"));
+        target.addDnsServer(DNS2);
+        target.addRoute(new RouteInfo(GATEWAY1));
+        target.addRoute(new RouteInfo(GATEWAY2));
+        target.setMtu(MTU);
+        assertFalse(source.equals(target));
+
+        target.clear();
+        target.setInterfaceName(NAME);
+        target.addLinkAddress(LINKADDRV4);
+        target.addLinkAddress(LINKADDRV6);
+        target.addDnsServer(DNS1);
+        target.addDnsServer(DNS2);
+        // change gateway
+        target.addRoute(new RouteInfo(NetworkUtils.numericToInetAddress("75.208.8.2")));
+        target.addRoute(new RouteInfo(GATEWAY2));
+        target.setMtu(MTU);
+        assertFalse(source.equals(target));
+
+        target.clear();
+        target.setInterfaceName(NAME);
+        target.addLinkAddress(LINKADDRV4);
+        target.addLinkAddress(LINKADDRV6);
+        target.addDnsServer(DNS1);
+        target.addDnsServer(DNS2);
+        target.addRoute(new RouteInfo(GATEWAY1));
+        target.addRoute(new RouteInfo(GATEWAY2));
+        // change mtu
+        target.setMtu(1440);
+        assertFalse(source.equals(target));
+    }
+
+    @Test
+    public void testEqualsDifferentOrder() throws Exception {
+        LinkProperties source = new LinkProperties();
+        source.setInterfaceName(NAME);
+        // set 2 link addresses
+        source.addLinkAddress(LINKADDRV4);
+        source.addLinkAddress(LINKADDRV6);
+        // set 2 dnses
+        source.addDnsServer(DNS1);
+        source.addDnsServer(DNS2);
+        // set 2 gateways
+        source.addRoute(new RouteInfo(GATEWAY1));
+        source.addRoute(new RouteInfo(GATEWAY2));
+        source.setMtu(MTU);
+
+        LinkProperties target = new LinkProperties();
+        // Exchange order
+        target.setInterfaceName(NAME);
+        target.addLinkAddress(LINKADDRV6);
+        target.addLinkAddress(LINKADDRV4);
+        target.addDnsServer(DNS2);
+        target.addDnsServer(DNS1);
+        target.addRoute(new RouteInfo(GATEWAY2));
+        target.addRoute(new RouteInfo(GATEWAY1));
+        target.setMtu(MTU);
+
+        assertLinkPropertiesEqual(source, target);
+    }
+
+    @Test
+    public void testEqualsDuplicated() throws Exception {
+        LinkProperties source = new LinkProperties();
+        // set 3 link addresses, eg, [A, A, B]
+        source.addLinkAddress(LINKADDRV4);
+        source.addLinkAddress(LINKADDRV4);
+        source.addLinkAddress(LINKADDRV6);
+
+        LinkProperties target = new LinkProperties();
+        // set 3 link addresses, eg, [A, B, B]
+        target.addLinkAddress(LINKADDRV4);
+        target.addLinkAddress(LINKADDRV6);
+        target.addLinkAddress(LINKADDRV6);
+
+        assertLinkPropertiesEqual(source, target);
+    }
+
+    private void assertAllRoutesHaveInterface(String iface, LinkProperties lp) {
+        for (RouteInfo r : lp.getRoutes()) {
+            assertEquals(iface, r.getInterface());
+        }
+    }
+
+    @Test
+    public void testRouteInterfaces() {
+        LinkAddress prefix = new LinkAddress(
+            NetworkUtils.numericToInetAddress("2001:db8::"), 32);
+        InetAddress address = ADDRV6;
+
+        // Add a route with no interface to a LinkProperties with no interface. No errors.
+        LinkProperties lp = new LinkProperties();
+        RouteInfo r = new RouteInfo(prefix, address, null);
+        assertTrue(lp.addRoute(r));
+        assertEquals(1, lp.getRoutes().size());
+        assertAllRoutesHaveInterface(null, lp);
+
+        // Adding the same route twice has no effect.
+        assertFalse(lp.addRoute(r));
+        assertEquals(1, lp.getRoutes().size());
+
+        // Add a route with an interface. Expect an exception.
+        r = new RouteInfo(prefix, address, "wlan0");
+        try {
+          lp.addRoute(r);
+          fail("Adding wlan0 route to LP with no interface, expect exception");
+        } catch (IllegalArgumentException expected) {}
+
+        // Change the interface name. All the routes should change their interface name too.
+        lp.setInterfaceName("rmnet0");
+        assertAllRoutesHaveInterface("rmnet0", lp);
+
+        // Now add a route with the wrong interface. This causes an exception too.
+        try {
+          lp.addRoute(r);
+          fail("Adding wlan0 route to rmnet0 LP, expect exception");
+        } catch (IllegalArgumentException expected) {}
+
+        // If the interface name matches, the route is added.
+        r = new RouteInfo(prefix, null, "wlan0");
+        lp.setInterfaceName("wlan0");
+        lp.addRoute(r);
+        assertEquals(2, lp.getRoutes().size());
+        assertAllRoutesHaveInterface("wlan0", lp);
+
+        // Routes with null interfaces are converted to wlan0.
+        r = RouteInfo.makeHostRoute(ADDRV6, null);
+        lp.addRoute(r);
+        assertEquals(3, lp.getRoutes().size());
+        assertAllRoutesHaveInterface("wlan0", lp);
+
+        // Check comparisons work.
+        LinkProperties lp2 = new LinkProperties(lp);
+        assertAllRoutesHaveInterface("wlan0", lp);
+        assertEquals(0, lp.compareAllRoutes(lp2).added.size());
+        assertEquals(0, lp.compareAllRoutes(lp2).removed.size());
+
+        lp2.setInterfaceName("p2p0");
+        assertAllRoutesHaveInterface("p2p0", lp2);
+        assertEquals(3, lp.compareAllRoutes(lp2).added.size());
+        assertEquals(3, lp.compareAllRoutes(lp2).removed.size());
+    }
+
+    @Test
+    public void testStackedInterfaces() {
+        LinkProperties rmnet0 = new LinkProperties();
+        rmnet0.setInterfaceName("rmnet0");
+        rmnet0.addLinkAddress(LINKADDRV6);
+
+        LinkProperties clat4 = new LinkProperties();
+        clat4.setInterfaceName("clat4");
+        clat4.addLinkAddress(LINKADDRV4);
+
+        assertEquals(0, rmnet0.getStackedLinks().size());
+        assertEquals(1, rmnet0.getAddresses().size());
+        assertEquals(1, rmnet0.getLinkAddresses().size());
+        assertEquals(1, rmnet0.getAllAddresses().size());
+        assertEquals(1, rmnet0.getAllLinkAddresses().size());
+
+        rmnet0.addStackedLink(clat4);
+        assertEquals(1, rmnet0.getStackedLinks().size());
+        assertEquals(1, rmnet0.getAddresses().size());
+        assertEquals(1, rmnet0.getLinkAddresses().size());
+        assertEquals(2, rmnet0.getAllAddresses().size());
+        assertEquals(2, rmnet0.getAllLinkAddresses().size());
+
+        rmnet0.addStackedLink(clat4);
+        assertEquals(1, rmnet0.getStackedLinks().size());
+        assertEquals(1, rmnet0.getAddresses().size());
+        assertEquals(1, rmnet0.getLinkAddresses().size());
+        assertEquals(2, rmnet0.getAllAddresses().size());
+        assertEquals(2, rmnet0.getAllLinkAddresses().size());
+
+        assertEquals(0, clat4.getStackedLinks().size());
+
+        // Modify an item in the returned collection to see what happens.
+        for (LinkProperties link : rmnet0.getStackedLinks()) {
+            if (link.getInterfaceName().equals("clat4")) {
+               link.setInterfaceName("newname");
+            }
+        }
+        for (LinkProperties link : rmnet0.getStackedLinks()) {
+            assertFalse("newname".equals(link.getInterfaceName()));
+        }
+
+        assertTrue(rmnet0.removeStackedLink("clat4"));
+        assertEquals(0, rmnet0.getStackedLinks().size());
+        assertEquals(1, rmnet0.getAddresses().size());
+        assertEquals(1, rmnet0.getLinkAddresses().size());
+        assertEquals(1, rmnet0.getAllAddresses().size());
+        assertEquals(1, rmnet0.getAllLinkAddresses().size());
+
+        assertFalse(rmnet0.removeStackedLink("clat4"));
+    }
+
+    private LinkAddress getFirstLinkAddress(LinkProperties lp) {
+        return lp.getLinkAddresses().iterator().next();
+    }
+
+    @Test
+    public void testAddressMethods() {
+        LinkProperties lp = new LinkProperties();
+
+        // No addresses.
+        assertFalse(lp.hasIPv4Address());
+        assertFalse(lp.hasGlobalIPv6Address());
+
+        // Addresses on stacked links don't count.
+        LinkProperties stacked = new LinkProperties();
+        stacked.setInterfaceName("stacked");
+        lp.addStackedLink(stacked);
+        stacked.addLinkAddress(LINKADDRV4);
+        stacked.addLinkAddress(LINKADDRV6);
+        assertTrue(stacked.hasIPv4Address());
+        assertTrue(stacked.hasGlobalIPv6Address());
+        assertFalse(lp.hasIPv4Address());
+        assertFalse(lp.hasGlobalIPv6Address());
+        lp.removeStackedLink("stacked");
+        assertFalse(lp.hasIPv4Address());
+        assertFalse(lp.hasGlobalIPv6Address());
+
+        // Addresses on the base link.
+        // Check the return values of hasIPvXAddress and ensure the add/remove methods return true
+        // iff something changes.
+        assertEquals(0, lp.getLinkAddresses().size());
+        assertTrue(lp.addLinkAddress(LINKADDRV6));
+        assertEquals(1, lp.getLinkAddresses().size());
+        assertFalse(lp.hasIPv4Address());
+        assertTrue(lp.hasGlobalIPv6Address());
+
+        assertTrue(lp.removeLinkAddress(LINKADDRV6));
+        assertEquals(0, lp.getLinkAddresses().size());
+
+        assertTrue(lp.addLinkAddress(LINKADDRV6LINKLOCAL));
+        assertEquals(1, lp.getLinkAddresses().size());
+        assertFalse(lp.hasGlobalIPv6Address());
+
+        assertTrue(lp.addLinkAddress(LINKADDRV4));
+        assertEquals(2, lp.getLinkAddresses().size());
+        assertTrue(lp.hasIPv4Address());
+        assertFalse(lp.hasGlobalIPv6Address());
+
+        assertTrue(lp.addLinkAddress(LINKADDRV6));
+        assertEquals(3, lp.getLinkAddresses().size());
+        assertTrue(lp.hasIPv4Address());
+        assertTrue(lp.hasGlobalIPv6Address());
+
+        assertTrue(lp.removeLinkAddress(LINKADDRV6LINKLOCAL));
+        assertEquals(2, lp.getLinkAddresses().size());
+        assertTrue(lp.hasIPv4Address());
+        assertTrue(lp.hasGlobalIPv6Address());
+
+        // Adding an address twice has no effect.
+        // Removing an address that's not present has no effect.
+        assertFalse(lp.addLinkAddress(LINKADDRV4));
+        assertEquals(2, lp.getLinkAddresses().size());
+        assertTrue(lp.hasIPv4Address());
+        assertTrue(lp.removeLinkAddress(LINKADDRV4));
+        assertEquals(1, lp.getLinkAddresses().size());
+        assertFalse(lp.hasIPv4Address());
+        assertFalse(lp.removeLinkAddress(LINKADDRV4));
+        assertEquals(1, lp.getLinkAddresses().size());
+
+        // Adding an address that's already present but with different properties causes the
+        // existing address to be updated and returns true.
+        // Start with only LINKADDRV6.
+        assertEquals(1, lp.getLinkAddresses().size());
+        assertEquals(LINKADDRV6, getFirstLinkAddress(lp));
+
+        // Create a LinkAddress object for the same address, but with different flags.
+        LinkAddress deprecated = new LinkAddress(ADDRV6, 128,
+                OsConstants.IFA_F_DEPRECATED, OsConstants.RT_SCOPE_UNIVERSE);
+        assertTrue(deprecated.isSameAddressAs(LINKADDRV6));
+        assertFalse(deprecated.equals(LINKADDRV6));
+
+        // Check that adding it updates the existing address instead of adding a new one.
+        assertTrue(lp.addLinkAddress(deprecated));
+        assertEquals(1, lp.getLinkAddresses().size());
+        assertEquals(deprecated, getFirstLinkAddress(lp));
+        assertFalse(LINKADDRV6.equals(getFirstLinkAddress(lp)));
+
+        // Removing LINKADDRV6 removes deprecated, because removing addresses ignores properties.
+        assertTrue(lp.removeLinkAddress(LINKADDRV6));
+        assertEquals(0, lp.getLinkAddresses().size());
+    }
+
+    @Test
+    public void testSetLinkAddresses() {
+        LinkProperties lp = new LinkProperties();
+        lp.addLinkAddress(LINKADDRV4);
+        lp.addLinkAddress(LINKADDRV6);
+
+        LinkProperties lp2 = new LinkProperties();
+        lp2.addLinkAddress(LINKADDRV6);
+
+        assertFalse(lp.equals(lp2));
+
+        lp2.setLinkAddresses(lp.getLinkAddresses());
+        assertTrue(lp.equals(lp));
+    }
+
+    @Test
+    public void testIsProvisioned() {
+        LinkProperties lp4 = new LinkProperties();
+        assertFalse("v4only:empty", lp4.isProvisioned());
+        lp4.addLinkAddress(LINKADDRV4);
+        assertFalse("v4only:addr-only", lp4.isProvisioned());
+        lp4.addDnsServer(DNS1);
+        assertFalse("v4only:addr+dns", lp4.isProvisioned());
+        lp4.addRoute(new RouteInfo(GATEWAY1));
+        assertTrue("v4only:addr+dns+route", lp4.isProvisioned());
+        assertTrue("v4only:addr+dns+route", lp4.isIPv4Provisioned());
+        assertFalse("v4only:addr+dns+route", lp4.isIPv6Provisioned());
+
+        LinkProperties lp6 = new LinkProperties();
+        assertFalse("v6only:empty", lp6.isProvisioned());
+        lp6.addLinkAddress(LINKADDRV6LINKLOCAL);
+        assertFalse("v6only:fe80-only", lp6.isProvisioned());
+        lp6.addDnsServer(DNS6);
+        assertFalse("v6only:fe80+dns", lp6.isProvisioned());
+        lp6.addRoute(new RouteInfo(GATEWAY61));
+        assertFalse("v6only:fe80+dns+route", lp6.isProvisioned());
+        lp6.addLinkAddress(LINKADDRV6);
+        assertTrue("v6only:fe80+global+dns+route", lp6.isIPv6Provisioned());
+        assertTrue("v6only:fe80+global+dns+route", lp6.isProvisioned());
+        lp6.removeLinkAddress(LINKADDRV6LINKLOCAL);
+        assertFalse("v6only:global+dns+route", lp6.isIPv4Provisioned());
+        assertTrue("v6only:global+dns+route", lp6.isIPv6Provisioned());
+        assertTrue("v6only:global+dns+route", lp6.isProvisioned());
+
+        LinkProperties lp46 = new LinkProperties();
+        lp46.addLinkAddress(LINKADDRV4);
+        lp46.addLinkAddress(LINKADDRV6);
+        lp46.addDnsServer(DNS1);
+        lp46.addDnsServer(DNS6);
+        assertFalse("dualstack:missing-routes", lp46.isProvisioned());
+        lp46.addRoute(new RouteInfo(GATEWAY1));
+        assertTrue("dualstack:v4-provisioned", lp46.isIPv4Provisioned());
+        assertFalse("dualstack:v4-provisioned", lp46.isIPv6Provisioned());
+        assertTrue("dualstack:v4-provisioned", lp46.isProvisioned());
+        lp46.addRoute(new RouteInfo(GATEWAY61));
+        assertTrue("dualstack:both-provisioned", lp46.isIPv4Provisioned());
+        assertTrue("dualstack:both-provisioned", lp46.isIPv6Provisioned());
+        assertTrue("dualstack:both-provisioned", lp46.isProvisioned());
+
+        // A link with an IPv6 address and default route, but IPv4 DNS server.
+        LinkProperties mixed = new LinkProperties();
+        mixed.addLinkAddress(LINKADDRV6);
+        mixed.addDnsServer(DNS1);
+        mixed.addRoute(new RouteInfo(GATEWAY61));
+        assertFalse("mixed:addr6+route6+dns4", mixed.isIPv4Provisioned());
+        assertFalse("mixed:addr6+route6+dns4", mixed.isIPv6Provisioned());
+        assertFalse("mixed:addr6+route6+dns4", mixed.isProvisioned());
+    }
+
+    @Test
+    public void testCompareProvisioning() {
+        LinkProperties v4lp = new LinkProperties();
+        v4lp.addLinkAddress(LINKADDRV4);
+        v4lp.addRoute(new RouteInfo(GATEWAY1));
+        v4lp.addDnsServer(DNS1);
+        assertTrue(v4lp.isProvisioned());
+
+        LinkProperties v4r = new LinkProperties(v4lp);
+        v4r.removeDnsServer(DNS1);
+        assertFalse(v4r.isProvisioned());
+
+        assertEquals(ProvisioningChange.STILL_NOT_PROVISIONED,
+                LinkProperties.compareProvisioning(v4r, v4r));
+        assertEquals(ProvisioningChange.LOST_PROVISIONING,
+                LinkProperties.compareProvisioning(v4lp, v4r));
+        assertEquals(ProvisioningChange.GAINED_PROVISIONING,
+                LinkProperties.compareProvisioning(v4r, v4lp));
+        assertEquals(ProvisioningChange.STILL_PROVISIONED,
+                LinkProperties.compareProvisioning(v4lp, v4lp));
+
+        // Check that losing IPv4 provisioning on a dualstack network is
+        // seen as a total loss of provisioning.
+        LinkProperties v6lp = new LinkProperties();
+        v6lp.addLinkAddress(LINKADDRV6);
+        v6lp.addRoute(new RouteInfo(GATEWAY61));
+        v6lp.addDnsServer(DNS6);
+        assertFalse(v6lp.isIPv4Provisioned());
+        assertTrue(v6lp.isIPv6Provisioned());
+        assertTrue(v6lp.isProvisioned());
+
+        LinkProperties v46lp = new LinkProperties(v6lp);
+        v46lp.addLinkAddress(LINKADDRV4);
+        v46lp.addRoute(new RouteInfo(GATEWAY1));
+        v46lp.addDnsServer(DNS1);
+        assertTrue(v46lp.isIPv4Provisioned());
+        assertTrue(v46lp.isIPv6Provisioned());
+        assertTrue(v46lp.isProvisioned());
+
+        assertEquals(ProvisioningChange.STILL_PROVISIONED,
+                LinkProperties.compareProvisioning(v4lp, v46lp));
+        assertEquals(ProvisioningChange.STILL_PROVISIONED,
+                LinkProperties.compareProvisioning(v6lp, v46lp));
+        assertEquals(ProvisioningChange.LOST_PROVISIONING,
+                LinkProperties.compareProvisioning(v46lp, v6lp));
+        assertEquals(ProvisioningChange.LOST_PROVISIONING,
+                LinkProperties.compareProvisioning(v46lp, v4lp));
+
+        // Check that losing and gaining a secondary router does not change
+        // the provisioning status.
+        LinkProperties v6lp2 = new LinkProperties(v6lp);
+        v6lp2.addRoute(new RouteInfo(GATEWAY62));
+        assertTrue(v6lp2.isProvisioned());
+
+        assertEquals(ProvisioningChange.STILL_PROVISIONED,
+                LinkProperties.compareProvisioning(v6lp2, v6lp));
+        assertEquals(ProvisioningChange.STILL_PROVISIONED,
+                LinkProperties.compareProvisioning(v6lp, v6lp2));
+    }
+
+    @Test
+    public void testIsReachable() {
+        final LinkProperties v4lp = new LinkProperties();
+        assertFalse(v4lp.isReachable(DNS1));
+        assertFalse(v4lp.isReachable(DNS2));
+
+        // Add an on-link route, making the on-link DNS server reachable,
+        // but there is still no IPv4 address.
+        assertTrue(v4lp.addRoute(new RouteInfo(
+                new IpPrefix(NetworkUtils.numericToInetAddress("75.208.0.0"), 16))));
+        assertFalse(v4lp.isReachable(DNS1));
+        assertFalse(v4lp.isReachable(DNS2));
+
+        // Adding an IPv4 address (right now, any IPv4 address) means we use
+        // the routes to compute likely reachability.
+        assertTrue(v4lp.addLinkAddress(new LinkAddress(ADDRV4, 16)));
+        assertTrue(v4lp.isReachable(DNS1));
+        assertFalse(v4lp.isReachable(DNS2));
+
+        // Adding a default route makes the off-link DNS server reachable.
+        assertTrue(v4lp.addRoute(new RouteInfo(GATEWAY1)));
+        assertTrue(v4lp.isReachable(DNS1));
+        assertTrue(v4lp.isReachable(DNS2));
+
+        final LinkProperties v6lp = new LinkProperties();
+        final InetAddress kLinkLocalDns = NetworkUtils.numericToInetAddress("fe80::6:1");
+        final InetAddress kLinkLocalDnsWithScope = NetworkUtils.numericToInetAddress("fe80::6:2%43");
+        final InetAddress kOnLinkDns = NetworkUtils.numericToInetAddress("2001:db8:85a3::53");
+        assertFalse(v6lp.isReachable(kLinkLocalDns));
+        assertFalse(v6lp.isReachable(kLinkLocalDnsWithScope));
+        assertFalse(v6lp.isReachable(kOnLinkDns));
+        assertFalse(v6lp.isReachable(DNS6));
+
+        // Add a link-local route, making the link-local DNS servers reachable. Because
+        // we assume the presence of an IPv6 link-local address, link-local DNS servers
+        // are considered reachable, but only those with a non-zero scope identifier.
+        assertTrue(v6lp.addRoute(new RouteInfo(
+                new IpPrefix(NetworkUtils.numericToInetAddress("fe80::"), 64))));
+        assertFalse(v6lp.isReachable(kLinkLocalDns));
+        assertTrue(v6lp.isReachable(kLinkLocalDnsWithScope));
+        assertFalse(v6lp.isReachable(kOnLinkDns));
+        assertFalse(v6lp.isReachable(DNS6));
+
+        // Add a link-local address--nothing changes.
+        assertTrue(v6lp.addLinkAddress(LINKADDRV6LINKLOCAL));
+        assertFalse(v6lp.isReachable(kLinkLocalDns));
+        assertTrue(v6lp.isReachable(kLinkLocalDnsWithScope));
+        assertFalse(v6lp.isReachable(kOnLinkDns));
+        assertFalse(v6lp.isReachable(DNS6));
+
+        // Add a global route on link, but no global address yet. DNS servers reachable
+        // via a route that doesn't require a gateway: give them the benefit of the
+        // doubt and hope the link-local source address suffices for communication.
+        assertTrue(v6lp.addRoute(new RouteInfo(
+                new IpPrefix(NetworkUtils.numericToInetAddress("2001:db8:85a3::"), 64))));
+        assertFalse(v6lp.isReachable(kLinkLocalDns));
+        assertTrue(v6lp.isReachable(kLinkLocalDnsWithScope));
+        assertTrue(v6lp.isReachable(kOnLinkDns));
+        assertFalse(v6lp.isReachable(DNS6));
+
+        // Add a global address; the on-link global address DNS server is (still)
+        // presumed reachable.
+        assertTrue(v6lp.addLinkAddress(new LinkAddress(ADDRV6, 64)));
+        assertFalse(v6lp.isReachable(kLinkLocalDns));
+        assertTrue(v6lp.isReachable(kLinkLocalDnsWithScope));
+        assertTrue(v6lp.isReachable(kOnLinkDns));
+        assertFalse(v6lp.isReachable(DNS6));
+
+        // Adding a default route makes the off-link DNS server reachable.
+        assertTrue(v6lp.addRoute(new RouteInfo(GATEWAY62)));
+        assertFalse(v6lp.isReachable(kLinkLocalDns));
+        assertTrue(v6lp.isReachable(kLinkLocalDnsWithScope));
+        assertTrue(v6lp.isReachable(kOnLinkDns));
+        assertTrue(v6lp.isReachable(DNS6));
+
+        // Check isReachable on stacked links. This requires that the source IP address be assigned
+        // on the interface returned by the route lookup.
+        LinkProperties stacked = new LinkProperties();
+
+        // Can't add a stacked link without an interface name.
+        stacked.setInterfaceName("v4-test0");
+        v6lp.addStackedLink(stacked);
+
+        InetAddress stackedAddress = Address("192.0.0.4");
+        LinkAddress stackedLinkAddress = new LinkAddress(stackedAddress, 32);
+        assertFalse(v6lp.isReachable(stackedAddress));
+        stacked.addLinkAddress(stackedLinkAddress);
+        assertFalse(v6lp.isReachable(stackedAddress));
+        stacked.addRoute(new RouteInfo(stackedLinkAddress));
+        assertTrue(stacked.isReachable(stackedAddress));
+        assertTrue(v6lp.isReachable(stackedAddress));
+
+        assertFalse(v6lp.isReachable(DNS1));
+        stacked.addRoute(new RouteInfo((IpPrefix) null, stackedAddress));
+        assertTrue(v6lp.isReachable(DNS1));
+    }
+
+    @Test
+    public void testLinkPropertiesEnsureDirectlyConnectedRoutes() {
+        // IPv4 case: no route added initially
+        LinkProperties rmnet0 = new LinkProperties();
+        rmnet0.setInterfaceName("rmnet0");
+        rmnet0.addLinkAddress(new LinkAddress("10.0.0.2/8"));
+        RouteInfo directRoute0 = new RouteInfo(new IpPrefix("10.0.0.0/8"), null,
+                rmnet0.getInterfaceName());
+
+        // Since no routes is added explicitly, getAllRoutes() should return empty.
+        assertTrue(rmnet0.getAllRoutes().isEmpty());
+        rmnet0.ensureDirectlyConnectedRoutes();
+        // ensureDirectlyConnectedRoutes() should have added the missing local route.
+        assertEqualRoutes(Collections.singletonList(directRoute0), rmnet0.getAllRoutes());
+
+        // IPv4 case: both direct and default routes added initially
+        LinkProperties rmnet1 = new LinkProperties();
+        rmnet1.setInterfaceName("rmnet1");
+        rmnet1.addLinkAddress(new LinkAddress("10.0.0.3/8"));
+        RouteInfo defaultRoute1 = new RouteInfo((IpPrefix) null,
+                NetworkUtils.numericToInetAddress("10.0.0.1"), rmnet1.getInterfaceName());
+        RouteInfo directRoute1 = new RouteInfo(new IpPrefix("10.0.0.0/8"), null,
+                rmnet1.getInterfaceName());
+        rmnet1.addRoute(defaultRoute1);
+        rmnet1.addRoute(directRoute1);
+
+        // Check added routes
+        assertEqualRoutes(Arrays.asList(defaultRoute1, directRoute1), rmnet1.getAllRoutes());
+        // ensureDirectlyConnectedRoutes() shouldn't change the routes since direct connected
+        // route is already part of the configuration.
+        rmnet1.ensureDirectlyConnectedRoutes();
+        assertEqualRoutes(Arrays.asList(defaultRoute1, directRoute1), rmnet1.getAllRoutes());
+
+        // IPv6 case: only default routes added initially
+        LinkProperties rmnet2 = new LinkProperties();
+        rmnet2.setInterfaceName("rmnet2");
+        rmnet2.addLinkAddress(new LinkAddress("fe80::cafe/64"));
+        rmnet2.addLinkAddress(new LinkAddress("2001:db8::2/64"));
+        RouteInfo defaultRoute2 = new RouteInfo((IpPrefix) null,
+                NetworkUtils.numericToInetAddress("2001:db8::1"), rmnet2.getInterfaceName());
+        RouteInfo directRoute2 = new RouteInfo(new IpPrefix("2001:db8::/64"), null,
+                rmnet2.getInterfaceName());
+        RouteInfo linkLocalRoute2 = new RouteInfo(new IpPrefix("fe80::/64"), null,
+                rmnet2.getInterfaceName());
+        rmnet2.addRoute(defaultRoute2);
+
+        assertEqualRoutes(Arrays.asList(defaultRoute2), rmnet2.getAllRoutes());
+        rmnet2.ensureDirectlyConnectedRoutes();
+        assertEqualRoutes(Arrays.asList(defaultRoute2, directRoute2, linkLocalRoute2),
+                rmnet2.getAllRoutes());
+
+        // Corner case: no interface name
+        LinkProperties rmnet3 = new LinkProperties();
+        rmnet3.addLinkAddress(new LinkAddress("192.168.0.2/24"));
+        RouteInfo directRoute3 = new RouteInfo(new IpPrefix("192.168.0.0/24"), null,
+                rmnet3.getInterfaceName());
+
+        assertTrue(rmnet3.getAllRoutes().isEmpty());
+        rmnet3.ensureDirectlyConnectedRoutes();
+        assertEqualRoutes(Collections.singletonList(directRoute3), rmnet3.getAllRoutes());
+
+    }
+
+    @Test
+    public void testCompareResult() {
+        // Either adding or removing items
+        compareResult(Arrays.asList(1, 2, 3, 4), Arrays.asList(1),
+                Arrays.asList(2, 3, 4), new ArrayList<>());
+        compareResult(Arrays.asList(1, 2), Arrays.asList(3, 2, 1, 4),
+                new ArrayList<>(), Arrays.asList(3, 4));
+
+
+        // adding and removing items at the same time
+        compareResult(Arrays.asList(1, 2, 3, 4), Arrays.asList(2, 3, 4, 5),
+                Arrays.asList(1), Arrays.asList(5));
+        compareResult(Arrays.asList(1, 2, 3), Arrays.asList(4, 5, 6),
+                Arrays.asList(1, 2, 3), Arrays.asList(4, 5, 6));
+
+        // null cases
+        compareResult(Arrays.asList(1, 2, 3), null, Arrays.asList(1, 2, 3), new ArrayList<>());
+        compareResult(null, Arrays.asList(3, 2, 1), new ArrayList<>(), Arrays.asList(1, 2, 3));
+        compareResult(null, null, new ArrayList<>(), new ArrayList<>());
+    }
+
+    private void assertEqualRoutes(Collection<RouteInfo> expected, Collection<RouteInfo> actual) {
+        Set<RouteInfo> expectedSet = new ArraySet<>(expected);
+        Set<RouteInfo> actualSet = new ArraySet<>(actual);
+        // Duplicated entries in actual routes are considered failures
+        assertEquals(actual.size(), actualSet.size());
+
+        assertEquals(expectedSet, actualSet);
+    }
+
+    private <T> void compareResult(List<T> oldItems, List<T> newItems, List<T> expectRemoved,
+            List<T> expectAdded) {
+        CompareResult<T> result = new CompareResult<>(oldItems, newItems);
+        assertEquals(new ArraySet<>(expectAdded), new ArraySet<>(result.added));
+        assertEquals(new ArraySet<>(expectRemoved), (new ArraySet<>(result.removed)));
+    }
+}