Merge "Prevent changes to immutable capabilities for carrier wifi" am: 9e7e3b780d

Original change: https://android-review.googlesource.com/c/platform/frameworks/base/+/1661227

Change-Id: Iac1b1cf962eedc5a6f5e172a508b7bf7402e48b7

services/core/java/com/android/server/VcnManagementService.java

@@ -16,6 +16,8 @@
 
 package com.android.server;
 
+import static android.net.NetworkCapabilities.NET_CAPABILITY_NOT_RESTRICTED;
+import static android.net.NetworkCapabilities.TRANSPORT_WIFI;
 import static android.net.vcn.VcnManager.VCN_STATUS_CODE_ACTIVE;
 import static android.net.vcn.VcnManager.VCN_STATUS_CODE_INACTIVE;
 import static android.net.vcn.VcnManager.VCN_STATUS_CODE_NOT_CONFIGURED;
@@ -35,7 +37,9 @@ import android.content.Intent;
 import android.content.IntentFilter;
 import android.net.ConnectivityManager;
 import android.net.LinkProperties;
+import android.net.Network;
 import android.net.NetworkCapabilities;
+import android.net.NetworkRequest;
 import android.net.vcn.IVcnManagementService;
 import android.net.vcn.IVcnStatusCallback;
 import android.net.vcn.IVcnUnderlyingNetworkPolicyListener;
@@ -161,6 +165,9 @@ public class VcnManagementService extends IVcnManagementService.Stub {
     @NonNull private final VcnContext mVcnContext;
     @NonNull private final BroadcastReceiver mPkgChangeReceiver;
 
+    @NonNull
+    private final TrackingNetworkCallback mTrackingNetworkCallback = new TrackingNetworkCallback();
+
     /** Can only be assigned when {@link #systemReady()} is called, since it uses AppOpsManager. */
     @Nullable private LocationPermissionChecker mLocationPermissionChecker;
 
@@ -357,6 +364,10 @@ public class VcnManagementService extends IVcnManagementService.Stub {
     public void systemReady() {
         mContext.getSystemService(ConnectivityManager.class)
                 .registerNetworkProvider(mNetworkProvider);
+        mContext.getSystemService(ConnectivityManager.class)
+                .registerNetworkCallback(
+                        new NetworkRequest.Builder().clearCapabilities().build(),
+                        mTrackingNetworkCallback);
         mTelephonySubscriptionTracker.register();
         mLocationPermissionChecker = mDeps.newLocationPermissionChecker(mVcnContext.getContext());
     }
@@ -792,8 +803,9 @@ public class VcnManagementService extends IVcnManagementService.Stub {
                         NetworkCapabilities.NET_CAPABILITY_NOT_RESTRICTED);
             }
 
+            final NetworkCapabilities result = ncBuilder.build();
             return new VcnUnderlyingNetworkPolicy(
-                    false /* isTearDownRequested */, ncBuilder.build());
+                    mTrackingNetworkCallback.requiresRestartForCarrierWifi(result), result);
         });
     }
 
@@ -940,6 +952,49 @@ public class VcnManagementService extends IVcnManagementService.Stub {
                 @Nullable String exceptionMessage);
     }
 
+    /**
+     * TrackingNetworkCallback tracks all active networks
+     *
+     * <p>This is used to ensure that no underlying networks have immutable capabilities changed
+     * without requiring a Network restart.
+     */
+    private class TrackingNetworkCallback extends ConnectivityManager.NetworkCallback {
+        private final Map<Network, NetworkCapabilities> mCaps = new ArrayMap<>();
+
+        @Override
+        public void onCapabilitiesChanged(Network network, NetworkCapabilities caps) {
+            synchronized (mCaps) {
+                mCaps.put(network, caps);
+            }
+        }
+
+        @Override
+        public void onLost(Network network) {
+            synchronized (mCaps) {
+                mCaps.remove(network);
+            }
+        }
+
+        private boolean requiresRestartForCarrierWifi(NetworkCapabilities caps) {
+            if (!caps.hasTransport(TRANSPORT_WIFI) || caps.getSubIds() == null) {
+                return false;
+            }
+
+            synchronized (mCaps) {
+                for (NetworkCapabilities existing : mCaps.values()) {
+                    if (existing.hasTransport(TRANSPORT_WIFI)
+                            && caps.getSubIds().equals(existing.getSubIds())) {
+                        // Restart if any immutable capabilities have changed
+                        return existing.hasCapability(NET_CAPABILITY_NOT_RESTRICTED)
+                                != caps.hasCapability(NET_CAPABILITY_NOT_RESTRICTED);
+                    }
+                }
+            }
+
+            return false;
+        }
+    }
+
     /** VcnCallbackImpl for Vcn signals sent up to VcnManagementService. */
     private class VcnCallbackImpl implements VcnCallback {
         @NonNull private final ParcelUuid mSubGroup;

tests/vcn/java/com/android/server/VcnManagementServiceTest.java

@@ -16,6 +16,8 @@
 
 package com.android.server;
 
+import static android.net.ConnectivityManager.NetworkCallback;
+import static android.net.NetworkCapabilities.NET_CAPABILITY_NOT_RESTRICTED;
 import static android.net.NetworkCapabilities.NET_CAPABILITY_NOT_VCN_MANAGED;
 import static android.net.NetworkCapabilities.TRANSPORT_CELLULAR;
 import static android.net.NetworkCapabilities.TRANSPORT_WIFI;
@@ -55,8 +57,10 @@ import android.content.Context;
 import android.content.Intent;
 import android.net.ConnectivityManager;
 import android.net.LinkProperties;
+import android.net.Network;
 import android.net.NetworkCapabilities;
 import android.net.NetworkCapabilities.Transport;
+import android.net.NetworkRequest;
 import android.net.TelephonyNetworkSpecifier;
 import android.net.vcn.IVcnStatusCallback;
 import android.net.vcn.IVcnUnderlyingNetworkPolicyListener;
@@ -258,6 +262,10 @@ public class VcnManagementServiceTest {
 
         verify(mConnMgr).registerNetworkProvider(any(VcnNetworkProvider.class));
         verify(mSubscriptionTracker).register();
+        verify(mConnMgr)
+                .registerNetworkCallback(
+                        eq(new NetworkRequest.Builder().clearCapabilities().build()),
+                        any(NetworkCallback.class));
     }
 
     @Test
@@ -706,10 +714,8 @@ public class VcnManagementServiceTest {
                 .checkLocationPermission(eq(TEST_PACKAGE_NAME), any(), eq(TEST_UID), any());
     }
 
-    private VcnUnderlyingNetworkPolicy startVcnAndGetPolicyForTransport(
+    private NetworkCapabilities.Builder getNetworkCapabilitiesBuilderForTransport(
-            int subId, ParcelUuid subGrp, boolean isVcnActive, int transport) {
+            int subId, int transport) {
-        setupSubscriptionAndStartVcn(subId, subGrp, isVcnActive);
-
         final NetworkCapabilities.Builder ncBuilder =
                 new NetworkCapabilities.Builder()
                         .addCapability(NET_CAPABILITY_NOT_VCN_MANAGED)
@@ -718,7 +724,16 @@ public class VcnManagementServiceTest {
             ncBuilder.setSubIds(Collections.singleton(subId));
         }
 
-        return mVcnMgmtSvc.getUnderlyingNetworkPolicy(ncBuilder.build(), new LinkProperties());
+        return ncBuilder;
+    }
+
+    private VcnUnderlyingNetworkPolicy startVcnAndGetPolicyForTransport(
+            int subId, ParcelUuid subGrp, boolean isVcnActive, int transport) {
+        setupSubscriptionAndStartVcn(subId, subGrp, isVcnActive);
+
+        return mVcnMgmtSvc.getUnderlyingNetworkPolicy(
+                getNetworkCapabilitiesBuilderForTransport(subId, transport).build(),
+                new LinkProperties());
     }
 
     @Test
@@ -780,6 +795,53 @@ public class VcnManagementServiceTest {
                 true /* isRestricted */);
     }
 
+    private void setupTrackedCarrierWifiNetwork(NetworkCapabilities caps) {
+        mVcnMgmtSvc.systemReady();
+
+        final ArgumentCaptor<NetworkCallback> captor =
+                ArgumentCaptor.forClass(NetworkCallback.class);
+        verify(mConnMgr)
+                .registerNetworkCallback(
+                        eq(new NetworkRequest.Builder().clearCapabilities().build()),
+                        captor.capture());
+        captor.getValue().onCapabilitiesChanged(new Network(0), caps);
+    }
+
+    @Test
+    public void testGetUnderlyingNetworkPolicyVcnWifi_unrestrictingExistingNetworkRequiresRestart()
+            throws Exception {
+        final NetworkCapabilities existingNetworkCaps =
+                getNetworkCapabilitiesBuilderForTransport(TEST_SUBSCRIPTION_ID, TRANSPORT_WIFI)
+                        .removeCapability(NET_CAPABILITY_NOT_RESTRICTED)
+                        .build();
+        setupTrackedCarrierWifiNetwork(existingNetworkCaps);
+
+        // Trigger test without VCN instance alive; expect restart due to change of NOT_RESTRICTED
+        // immutable capability
+        final VcnUnderlyingNetworkPolicy policy =
+                mVcnMgmtSvc.getUnderlyingNetworkPolicy(
+                        getNetworkCapabilitiesBuilderForTransport(
+                                        TEST_SUBSCRIPTION_ID, TRANSPORT_WIFI)
+                                .build(),
+                        new LinkProperties());
+        assertTrue(policy.isTeardownRequested());
+    }
+
+    @Test
+    public void testGetUnderlyingNetworkPolicyVcnWifi_restrictingExistingNetworkRequiresRestart()
+            throws Exception {
+        final NetworkCapabilities existingNetworkCaps =
+                getNetworkCapabilitiesBuilderForTransport(TEST_SUBSCRIPTION_ID, TRANSPORT_WIFI)
+                        .build();
+        setupTrackedCarrierWifiNetwork(existingNetworkCaps);
+
+        final VcnUnderlyingNetworkPolicy policy =
+                startVcnAndGetPolicyForTransport(
+                        TEST_SUBSCRIPTION_ID, TEST_UUID_2, false /* isActive */, TRANSPORT_WIFI);
+
+        assertTrue(policy.isTeardownRequested());
+    }
+
     @Test
     public void testGetUnderlyingNetworkPolicyNonVcnNetwork() throws Exception {
         setupSubscriptionAndStartVcn(TEST_SUBSCRIPTION_ID, TEST_UUID_1, true /* isActive */);