Block camera access for apps running on VirtualDevices (d1528caf) · Commits · e / os / android_frameworks_base

core/res/res/values/strings.xml

+4 −0

Original line number	Diff line number	Diff line
		@@ -6266,4 +6266,8 @@ ul.</string>
		</string>
		<!-- Action label of notification for user to check background apps. [CHAR LIMIT=NONE] -->
		<string name="notification_action_check_bg_apps">Check active apps</string>

		<!-- Strings for VirtualDeviceManager -->
		<!-- Error message indicating the camera cannot be accessed when running on a virtual device. [CHAR LIMIT=NONE] -->
		<string name="vdm_camera_access_denied">Cannot access camera from this device</string>
		</resources>

core/res/res/values/symbols.xml

+3 −0

Original line number	Diff line number	Diff line
		@@ -4724,5 +4724,8 @@
		<java-symbol type="bool" name="config_lowPowerStandbyEnabledByDefault" />
		<java-symbol type="integer" name="config_lowPowerStandbyNonInteractiveTimeout" />

		<!-- For VirtualDeviceManager -->
		<java-symbol type="string" name="vdm_camera_access_denied" />

		<java-symbol type="color" name="camera_privacy_light"/>
		</resources>

services/companion/java/com/android/server/companion/virtual/CameraAccessController.java

0 → 100644

+212 −0

Original line number	Diff line number	Diff line
		/*
		* Copyright (C) 2022 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.companion.virtual;

		import static android.hardware.camera2.CameraInjectionSession.InjectionStatusCallback.ERROR_INJECTION_UNSUPPORTED;

		import android.annotation.NonNull;
		import android.content.Context;
		import android.content.pm.ApplicationInfo;
		import android.content.pm.PackageManager;
		import android.hardware.camera2.CameraAccessException;
		import android.hardware.camera2.CameraInjectionSession;
		import android.hardware.camera2.CameraManager;
		import android.util.ArrayMap;
		import android.util.Slog;

		import com.android.internal.annotations.GuardedBy;

		/**
		* Handles blocking access to the camera for apps running on virtual devices.
		*/
		class CameraAccessController extends CameraManager.AvailabilityCallback {
		private static final String TAG = "CameraAccessController";

		private final Object mLock = new Object();

		private final Context mContext;
		private VirtualDeviceManagerInternal mVirtualDeviceManagerInternal;
		CameraAccessBlockedCallback mBlockedCallback;
		private CameraManager mCameraManager;
		private boolean mListeningForCameraEvents;
		private PackageManager mPackageManager;

		@GuardedBy("mLock")
		private ArrayMap<String, InjectionSessionData> mPackageToSessionData = new ArrayMap<>();

		static class InjectionSessionData {
		public int appUid;
		public ArrayMap<String, CameraInjectionSession> cameraIdToSession = new ArrayMap<>();
		}

		interface CameraAccessBlockedCallback {
		/**
		* Called whenever an app was blocked from accessing a camera.
		* @param appUid uid for the app which was blocked
		*/
		void onCameraAccessBlocked(int appUid);
		}

		CameraAccessController(Context context,
		VirtualDeviceManagerInternal virtualDeviceManagerInternal,
		CameraAccessBlockedCallback blockedCallback) {
		mContext = context;
		mVirtualDeviceManagerInternal = virtualDeviceManagerInternal;
		mBlockedCallback = blockedCallback;
		mCameraManager = mContext.getSystemService(CameraManager.class);
		mPackageManager = mContext.getPackageManager();
		}

		/**
		* Starts watching for camera access by uids running on a virtual device, if we were not
		* already doing so.
		*/
		public void startObservingIfNeeded() {
		synchronized (mLock) {
		if (!mListeningForCameraEvents) {
		mCameraManager.registerAvailabilityCallback(mContext.getMainExecutor(), this);
		mListeningForCameraEvents = true;
		}
		}
		}

		/**
		* Stop watching for camera access.
		*/
		public void stopObserving() {
		synchronized (mLock) {
		mCameraManager.unregisterAvailabilityCallback(this);
		mListeningForCameraEvents = false;
		}
		}

		@Override
		public void onCameraOpened(@NonNull String cameraId, @NonNull String packageName) {
		synchronized (mLock) {
		try {
		final ApplicationInfo ainfo =
		mPackageManager.getApplicationInfo(packageName, 0);
		InjectionSessionData data = mPackageToSessionData.get(packageName);
		if (!mVirtualDeviceManagerInternal.isAppRunningOnAnyVirtualDevice(ainfo.uid)) {
		CameraInjectionSession existingSession =
		(data != null) ? data.cameraIdToSession.get(cameraId) : null;
		if (existingSession != null) {
		existingSession.close();
		data.cameraIdToSession.remove(cameraId);
		if (data.cameraIdToSession.isEmpty()) {
		mPackageToSessionData.remove(packageName);
		}
		}
		return;
		}
		if (data == null) {
		data = new InjectionSessionData();
		data.appUid = ainfo.uid;
		mPackageToSessionData.put(packageName, data);
		}
		if (data.cameraIdToSession.containsKey(cameraId)) {
		return;
		}
		startBlocking(packageName, cameraId);
		} catch (PackageManager.NameNotFoundException e) {
		Slog.e(TAG, "onCameraOpened - unknown package " + packageName, e);
		return;
		}
		}
		}

		@Override
		public void onCameraClosed(@NonNull String cameraId) {
		synchronized (mLock) {
		for (int i = mPackageToSessionData.size() - 1; i >= 0; i--) {
		InjectionSessionData data = mPackageToSessionData.valueAt(i);
		CameraInjectionSession session = data.cameraIdToSession.get(cameraId);
		if (session != null) {
		session.close();
		data.cameraIdToSession.remove(cameraId);
		if (data.cameraIdToSession.isEmpty()) {
		mPackageToSessionData.removeAt(i);
		}
		}
		}
		}
		}

		/**
		* Turns on blocking for a particular camera and package.
		*/
		private void startBlocking(String packageName, String cameraId) {
		try {
		mCameraManager.injectCamera(packageName, cameraId, /* externalCamId */ "",
		mContext.getMainExecutor(),
		new CameraInjectionSession.InjectionStatusCallback() {
		@Override
		public void onInjectionSucceeded(
		@NonNull CameraInjectionSession session) {
		CameraAccessController.this.onInjectionSucceeded(cameraId, packageName,
		session);
		}

		@Override
		public void onInjectionError(@NonNull int errorCode) {
		CameraAccessController.this.onInjectionError(cameraId, packageName,
		errorCode);
		}
		});
		} catch (CameraAccessException e) {
		Slog.e(TAG,
		"Failed to injectCamera for cameraId:" + cameraId + " package:" + packageName,
		e);
		}
		}

		private void onInjectionSucceeded(String cameraId, String packageName,
		@NonNull CameraInjectionSession session) {
		synchronized (mLock) {
		InjectionSessionData data = mPackageToSessionData.get(packageName);
		if (data == null) {
		Slog.e(TAG, "onInjectionSucceeded didn't find expected entry for package "
		+ packageName);
		session.close();
		return;
		}
		CameraInjectionSession existingSession = data.cameraIdToSession.put(cameraId, session);
		if (existingSession != null) {
		Slog.e(TAG, "onInjectionSucceeded found unexpected existing session for camera "
		+ cameraId);
		existingSession.close();
		}
		}
		}

		private void onInjectionError(String cameraId, String packageName, @NonNull int errorCode) {
		if (errorCode != ERROR_INJECTION_UNSUPPORTED) {
		// ERROR_INJECTION_UNSUPPORTED means that there wasn't an external camera to map to the
		// internal camera, which is expected when using the injection interface as we are in
		// this class to simply block camera access. Any other error is unexpected.
		Slog.e(TAG, "Unexpected injection error code:" + errorCode + " for camera:" + cameraId
		+ " and package:" + packageName);
		return;
		}
		synchronized (mLock) {
		InjectionSessionData data = mPackageToSessionData.get(packageName);
		if (data != null) {
		mBlockedCallback.onCameraAccessBlocked(data.appUid);
		}
		}
		}
		}

services/companion/java/com/android/server/companion/virtual/VirtualDeviceImpl.java

+23 −0

Original line number	Diff line number	Diff line
		@@ -24,6 +24,7 @@ import static android.view.WindowManager.LayoutParams.SYSTEM_FLAG_HIDE_NON_SYSTE

		import android.annotation.NonNull;
		import android.annotation.RequiresPermission;
		import android.annotation.StringRes;
		import android.app.Activity;
		import android.app.ActivityOptions;
		import android.app.PendingIntent;
		@@ -57,6 +58,8 @@ import android.util.ArrayMap;
		import android.util.ArraySet;
		import android.util.Slog;
		import android.util.SparseArray;
		import android.view.Display;
		import android.widget.Toast;
		import android.window.DisplayWindowPolicyController;

		import com.android.internal.annotations.GuardedBy;
		@@ -583,6 +586,26 @@ final class VirtualDeviceImpl extends IVirtualDevice.Stub
		return false;
		}

		/**
		* Shows a toast on virtual displays owned by this device which have a given uid running.
		*/
		void showToastWhereUidIsRunning(int uid, @StringRes int resId, @Toast.Duration int duration) {
		synchronized (mVirtualDeviceLock) {
		DisplayManager displayManager = mContext.getSystemService(DisplayManager.class);
		final int size = mWindowPolicyControllers.size();
		for (int i = 0; i < size; i++) {
		if (mWindowPolicyControllers.valueAt(i).containsUid(uid)) {
		int displayId = mWindowPolicyControllers.keyAt(i);
		Display display = displayManager.getDisplay(displayId);
		if (display != null && display.isValid()) {
		Toast.makeText(mContext.createDisplayContext(display), resId,
		duration).show();
		}
		}
		}
		}
		}

		interface OnDeviceCloseListener {
		void onClose(int associationId);
		}

services/companion/java/com/android/server/companion/virtual/VirtualDeviceManagerService.java

+21 −2

Original line number	Diff line number	Diff line
		@@ -39,6 +39,7 @@ import android.os.RemoteException;
		import android.util.ExceptionUtils;
		import android.util.Slog;
		import android.util.SparseArray;
		import android.widget.Toast;
		import android.window.DisplayWindowPolicyController;

		import com.android.internal.annotations.GuardedBy;
		@@ -62,8 +63,10 @@ public class VirtualDeviceManagerService extends SystemService {

		private final Object mVirtualDeviceManagerLock = new Object();
		private final VirtualDeviceManagerImpl mImpl;
		private VirtualDeviceManagerInternal mLocalService;
		private final Handler mHandler = new Handler(Looper.getMainLooper());
		private final PendingTrampolineMap mPendingTrampolines = new PendingTrampolineMap(mHandler);
		private final CameraAccessController mCameraAccessController;

		/**
		* Mapping from CDM association IDs to virtual devices. Only one virtual device is allowed for
		@@ -90,6 +93,9 @@ public class VirtualDeviceManagerService extends SystemService {
		public VirtualDeviceManagerService(Context context) {
		super(context);
		mImpl = new VirtualDeviceManagerImpl();
		mLocalService = new LocalService();
		mCameraAccessController = new CameraAccessController(getContext(), mLocalService,
		this::onCameraAccessBlocked);
		}

		private final ActivityInterceptorCallback mActivityInterceptorCallback =
		@@ -118,8 +124,7 @@ public class VirtualDeviceManagerService extends SystemService {
		@Override
		public void onStart() {
		publishBinderService(Context.VIRTUAL_DEVICE_SERVICE, mImpl);
		publishLocalService(VirtualDeviceManagerInternal.class, new LocalService());

		publishLocalService(VirtualDeviceManagerInternal.class, mLocalService);
		ActivityTaskManagerInternal activityTaskManagerInternal = getLocalService(
		ActivityTaskManagerInternal.class);
		activityTaskManagerInternal.registerActivityStartInterceptor(
		@@ -169,6 +174,16 @@ public class VirtualDeviceManagerService extends SystemService {
		}
		}

		void onCameraAccessBlocked(int appUid) {
		synchronized (mVirtualDeviceManagerLock) {
		int size = mVirtualDevices.size();
		for (int i = 0; i < size; i++) {
		mVirtualDevices.valueAt(i).showToastWhereUidIsRunning(appUid,
		com.android.internal.R.string.vdm_camera_access_denied, Toast.LENGTH_LONG);
		}
		}
		}

		class VirtualDeviceManagerImpl extends IVirtualDeviceManager.Stub implements
		VirtualDeviceImpl.PendingTrampolineCallback {

		@@ -205,10 +220,14 @@ public class VirtualDeviceManagerService extends SystemService {
		public void onClose(int associationId) {
		synchronized (mVirtualDeviceManagerLock) {
		mVirtualDevices.remove(associationId);
		if (mVirtualDevices.size() == 0) {
		mCameraAccessController.stopObserving();
		}
		}
		}
		},
		this, activityListener, params);
		mCameraAccessController.startObservingIfNeeded();
		mVirtualDevices.put(associationInfo.getId(), virtualDevice);
		return virtualDevice;
		}