From cacd5b0d2aee8ef74fdf3db22595cba5181c50d2 Mon Sep 17 00:00:00 2001
From: lucaslin <lucaslin@google.com>
Date: Fri, 15 Oct 2021 15:39:29 +0800
Subject: [PATCH] Test if underlying networks are the same as what VpnService
 sets

If VpnService set null as the underlying networks, then the
underlying networks will be set as system defeult network.
If VpnService set an empty array as the underlying networks, then
the underlying networks of VPN will not be set to any networks.
If VpnService set a network which is not null or an empty array,
then the underlying networks of VPN should be the same as this
one.

Bug: 191918368
Test: atest CtsHostsideNetworkTests:HostsideVpnTests
Change-Id: Ib2d54e53960e5f899cb8d4cfaa6705ca676354ca
---
 .../com/android/cts/net/hostside/VpnTest.java | 42 +++++++++++++++++++
 1 file changed, 42 insertions(+)

diff --git a/tests/cts/hostside/app/src/com/android/cts/net/hostside/VpnTest.java b/tests/cts/hostside/app/src/com/android/cts/net/hostside/VpnTest.java
index 00807b4fc4..311b3f0cb3 100755
--- a/tests/cts/hostside/app/src/com/android/cts/net/hostside/VpnTest.java
+++ b/tests/cts/hostside/app/src/com/android/cts/net/hostside/VpnTest.java
@@ -785,6 +785,15 @@ public class VpnTest {
         maybeExpectVpnTransportInfo(vpnNetwork);
         assertEquals(TYPE_VPN, mCM.getNetworkInfo(vpnNetwork).getType());
 
+        if (SdkLevel.isAtLeastT()) {
+            runWithShellPermissionIdentity(() -> {
+                final NetworkCapabilities nc = mCM.getNetworkCapabilities(vpnNetwork);
+                assertNotNull(nc);
+                assertNotNull(nc.getUnderlyingNetworks());
+                assertEquals(defaultNetwork, new ArrayList<>(nc.getUnderlyingNetworks()).get(0));
+            }, NETWORK_SETTINGS);
+        }
+
         if (SdkLevel.isAtLeastS()) {
             // Check that system default network callback has not seen any network changes, even
             // though the app's default network changed. Also check that otherUidCallback saw no
@@ -1017,6 +1026,15 @@ public class VpnTest {
         assertTrue(mCM.isActiveNetworkMetered());
 
         maybeExpectVpnTransportInfo(mCM.getActiveNetwork());
+
+        if (SdkLevel.isAtLeastT()) {
+            runWithShellPermissionIdentity(() -> {
+                final NetworkCapabilities nc = mCM.getNetworkCapabilities(mNetwork);
+                assertNotNull(nc);
+                assertNotNull(nc.getUnderlyingNetworks());
+                assertEquals(underlyingNetworks, new ArrayList<>(nc.getUnderlyingNetworks()));
+            }, NETWORK_SETTINGS);
+        }
     }
 
     @Test
@@ -1076,6 +1094,18 @@ public class VpnTest {
         assertEquals(isNetworkMetered(mNetwork), mCM.isActiveNetworkMetered());
 
         maybeExpectVpnTransportInfo(mCM.getActiveNetwork());
+
+        if (SdkLevel.isAtLeastT()) {
+            final Network vpnNetwork = mCM.getActiveNetwork();
+            assertNotEqual(underlyingNetwork, vpnNetwork);
+            runWithShellPermissionIdentity(() -> {
+                final NetworkCapabilities nc = mCM.getNetworkCapabilities(vpnNetwork);
+                assertNotNull(nc);
+                assertNotNull(nc.getUnderlyingNetworks());
+                final List<Network> underlying = nc.getUnderlyingNetworks();
+                assertEquals(underlyingNetwork, underlying.get(0));
+            }, NETWORK_SETTINGS);
+        }
     }
 
     @Test
@@ -1131,6 +1161,18 @@ public class VpnTest {
         assertTrue(mCM.isActiveNetworkMetered());
 
         maybeExpectVpnTransportInfo(mCM.getActiveNetwork());
+
+        if (SdkLevel.isAtLeastT()) {
+            final Network vpnNetwork = mCM.getActiveNetwork();
+            assertNotEqual(underlyingNetwork, vpnNetwork);
+            runWithShellPermissionIdentity(() -> {
+                final NetworkCapabilities nc = mCM.getNetworkCapabilities(vpnNetwork);
+                assertNotNull(nc);
+                assertNotNull(nc.getUnderlyingNetworks());
+                final List<Network> underlying = nc.getUnderlyingNetworks();
+                assertEquals(underlyingNetwork, underlying.get(0));
+            }, NETWORK_SETTINGS);
+        }
     }
 
     @Test