Move BackupAgent connection to a helper class (f658e370) · Commits · e / os / android_frameworks_base

services/backup/java/com/android/server/backup/BackupAgentConnectionManager.java

0 → 100644

+318 −0

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		/*
		* Copyright (C) 2017 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.backup;

		import static com.android.server.backup.BackupManagerService.MORE_DEBUG;
		import static com.android.server.backup.BackupManagerService.TAG;

		import android.annotation.Nullable;
		import android.app.ActivityManager;
		import android.app.ActivityManagerInternal;
		import android.app.ApplicationThreadConstants;
		import android.app.IActivityManager;
		import android.app.IBackupAgent;
		import android.app.backup.BackupAnnotations;
		import android.app.compat.CompatChanges;
		import android.compat.annotation.ChangeId;
		import android.compat.annotation.EnabledSince;
		import android.content.pm.ApplicationInfo;
		import android.content.pm.PackageManager;
		import android.content.pm.PackageManager.NameNotFoundException;
		import android.os.Binder;
		import android.os.Build;
		import android.os.IBinder;
		import android.os.Process;
		import android.os.RemoteException;
		import android.os.UserHandle;
		import android.util.ArraySet;
		import android.util.Slog;

		import com.android.internal.annotations.VisibleForTesting;
		import com.android.server.LocalServices;
		import com.android.server.backup.internal.LifecycleOperationStorage;

		import java.util.Set;

		/**
		* Handles the lifecycle of {@link IBackupAgent}s that the {@link UserBackupManagerService}
		* communicates with.
		*
		* <p>There can only be one agent that's connected to at a time.
		*
		* <p>There should be only one instance of this class per {@link UserBackupManagerService}.
		*/
		public class BackupAgentConnectionManager {

		/**
		* Enables the OS making a decision on whether backup restricted mode should be used for apps
		* that haven't explicitly opted in or out. See
		* {@link android.content.pm.PackageManager#PROPERTY_USE_RESTRICTED_BACKUP_MODE} for details.
		*/
		@ChangeId
		@EnabledSince(targetSdkVersion = Build.VERSION_CODES.BAKLAVA)
		public static final long OS_DECIDES_BACKUP_RESTRICTED_MODE = 376661510;

		// The thread performing the sequence of queued backups binds to each app's agent
		// in succession. Bind notifications are asynchronously delivered through the
		// Activity Manager; use this lock object to signal when a requested binding has
		// completed.
		private final Object mAgentConnectLock = new Object();
		private IBackupAgent mConnectedAgent;
		private volatile boolean mConnecting;
		private final ArraySet<String> mRestoreNoRestrictedModePackages = new ArraySet<>();
		private final ArraySet<String> mBackupNoRestrictedModePackages = new ArraySet<>();

		private final IActivityManager mActivityManager;
		private final ActivityManagerInternal mActivityManagerInternal;
		private final LifecycleOperationStorage mOperationStorage;
		private final PackageManager mPackageManager;
		private final UserBackupManagerService mUserBackupManagerService;
		private final int mUserId;
		private final String mUserIdMsg;

		BackupAgentConnectionManager(LifecycleOperationStorage operationStorage,
		PackageManager packageManager, UserBackupManagerService userBackupManagerService,
		int userId) {
		mActivityManager = ActivityManager.getService();
		mActivityManagerInternal = LocalServices.getService(ActivityManagerInternal.class);
		mOperationStorage = operationStorage;
		mPackageManager = packageManager;
		mUserBackupManagerService = userBackupManagerService;
		mUserId = userId;
		mUserIdMsg = "[UserID:" + userId + "] ";
		}

		/**
		* Fires off a backup agent, blocking until it attaches (and ActivityManager will call
		* {@link #agentConnected(String, IBinder)}) or until this operation times out.
		*
		* @param mode a {@code BACKUP_MODE} from {@link android.app.ApplicationThreadConstants}.
		*/
		@Nullable
		public IBackupAgent bindToAgentSynchronous(ApplicationInfo app, int mode,
		@BackupAnnotations.BackupDestination int backupDestination) {
		IBackupAgent agent = null;
		synchronized (mAgentConnectLock) {
		mConnecting = true;
		mConnectedAgent = null;
		boolean useRestrictedMode = shouldUseRestrictedBackupModeForPackage(mode,
		app.packageName);
		try {
		if (mActivityManager.bindBackupAgent(app.packageName, mode, mUserId,
		backupDestination, useRestrictedMode)) {
		Slog.d(TAG, mUserIdMsg + "awaiting agent for " + app);

		// success; wait for the agent to arrive
		// only wait 10 seconds for the bind to happen
		long timeoutMark = System.currentTimeMillis() + 10 * 1000;
		while (mConnecting && mConnectedAgent == null && (System.currentTimeMillis()
		< timeoutMark)) {
		try {
		mAgentConnectLock.wait(5000);
		} catch (InterruptedException e) {
		// just bail
		Slog.w(TAG, mUserIdMsg + "Interrupted: " + e);
		mConnecting = false;
		mConnectedAgent = null;
		}
		}

		// if we timed out with no connect, abort and move on
		if (mConnecting) {
		Slog.w(TAG, mUserIdMsg + "Timeout waiting for agent " + app);
		mConnectedAgent = null;
		}
		Slog.i(TAG, mUserIdMsg + "got agent " + mConnectedAgent);
		agent = mConnectedAgent;
		}
		} catch (RemoteException e) {
		// can't happen - ActivityManager is local
		}
		}
		if (agent == null) {
		mActivityManagerInternal.clearPendingBackup(mUserId);
		}
		return agent;
		}

		/**
		* Tell the ActivityManager that we are done with the {@link IBackupAgent} of this {@code app}.
		* It will tell the app to destroy the agent.
		*/
		public void unbindAgent(ApplicationInfo app) {
		try {
		mActivityManager.unbindBackupAgent(app);
		} catch (RemoteException e) {
		// Can't happen - activity manager is local
		}
		}

		/**
		* Callback: a requested backup agent has been instantiated. This should only be called from
		* the
		* {@link ActivityManager} when it's telling us that an agent is ready after a call to
		* {@link #bindToAgentSynchronous(ApplicationInfo, int, int)}.
		*/
		public void agentConnected(String packageName, IBinder agentBinder) {
		synchronized (mAgentConnectLock) {
		if (getCallingUid() == android.os.Process.SYSTEM_UID) {
		Slog.d(TAG,
		mUserIdMsg + "agentConnected pkg=" + packageName + " agent=" + agentBinder);
		mConnectedAgent = IBackupAgent.Stub.asInterface(agentBinder);
		mConnecting = false;
		} else {
		Slog.w(TAG, mUserIdMsg + "Non-system process uid=" + getCallingUid()
		+ " claiming agent connected");
		}
		mAgentConnectLock.notifyAll();
		}
		}

		/**
		* Callback: a backup agent has failed to come up, or has unexpectedly quit. If the agent failed
		* to come up in the first place, the agentBinder argument will be {@code null}. This should
		* only be called from the {@link ActivityManager}.
		*/
		public void agentDisconnected(String packageName) {
		synchronized (mAgentConnectLock) {
		if (getCallingUid() == Process.SYSTEM_UID) {
		mConnectedAgent = null;
		mConnecting = false;
		} else {
		Slog.w(TAG, mUserIdMsg + "Non-system process uid=" + getCallingUid()
		+ " claiming agent disconnected");
		}
		Slog.w(TAG, mUserIdMsg + "agentDisconnected: the backup agent for " + packageName
		+ " died: cancel current operations");

		// Offload operation cancellation off the main thread as the cancellation callbacks
		// might call out to BackupTransport. Other operations started on the same package
		// before the cancellation callback has executed will also be cancelled by the callback.
		Runnable cancellationRunnable = () -> {
		// handleCancel() causes the PerformFullTransportBackupTask to go on to
		// tearDownAgentAndKill: that will unbindBackupAgent in the Activity Manager, so
		// that the package being backed up doesn't get stuck in restricted mode until the
		// backup time-out elapses.
		for (int token : mOperationStorage.operationTokensForPackage(packageName)) {
		if (MORE_DEBUG) {
		Slog.d(TAG,
		mUserIdMsg + "agentDisconnected: will handleCancel(all) for token:"
		+ Integer.toHexString(token));
		}
		mUserBackupManagerService.handleCancel(token, true /* cancelAll */);
		}
		};
		getThreadForCancellation(cancellationRunnable).start();

		mAgentConnectLock.notifyAll();
		}
		}

		/**
		* Marks the given set of packages as packages that should not be put into restricted mode if
		* they are started for the given {@link BackupAnnotations.OperationType}.
		*/
		public void setNoRestrictedModePackages(Set<String> packageNames,
		@BackupAnnotations.OperationType int opType) {
		if (opType == BackupAnnotations.OperationType.BACKUP) {
		mBackupNoRestrictedModePackages.clear();
		mBackupNoRestrictedModePackages.addAll(packageNames);
		} else if (opType == BackupAnnotations.OperationType.RESTORE) {
		mRestoreNoRestrictedModePackages.clear();
		mRestoreNoRestrictedModePackages.addAll(packageNames);
		} else {
		throw new IllegalArgumentException("opType must be BACKUP or RESTORE");
		}
		}

		/**
		* Clears the list of packages that should not be put into restricted mode for either backup or
		* restore.
		*/
		public void clearNoRestrictedModePackages() {
		mBackupNoRestrictedModePackages.clear();
		mRestoreNoRestrictedModePackages.clear();
		}

		/**
		* If the app has specified {@link PackageManager#PROPERTY_USE_RESTRICTED_BACKUP_MODE}, then
		* its value is returned. If it hasn't and it targets an SDK below
		* {@link Build.VERSION_CODES#BAKLAVA} then returns true. If it targets a newer SDK, then
		* returns the decision made by the {@link android.app.backup.BackupTransport}.
		*
		* <p>When this method is called, we should have already asked the transport and cached its
		* response in {@link #mBackupNoRestrictedModePackages} or
		* {@link #mRestoreNoRestrictedModePackages} so this method will immediately return without
		* any IPC to the transport.
		*/
		private boolean shouldUseRestrictedBackupModeForPackage(
		@BackupAnnotations.OperationType int mode, String packageName) {
		if (!Flags.enableRestrictedModeChanges()) {
		return true;
		}

		// Key/Value apps are never put in restricted mode.
		if (mode == ApplicationThreadConstants.BACKUP_MODE_INCREMENTAL
		\|\| mode == ApplicationThreadConstants.BACKUP_MODE_RESTORE) {
		return false;
		}

		try {
		PackageManager.Property property = mPackageManager.getPropertyAsUser(
		PackageManager.PROPERTY_USE_RESTRICTED_BACKUP_MODE,
		packageName, /* className= */ null, mUserId);
		if (property.isBoolean()) {
		// If the package has explicitly specified, we won't ask the transport.
		return property.getBoolean();
		} else {
		Slog.w(TAG,
		PackageManager.PROPERTY_USE_RESTRICTED_BACKUP_MODE + "must be a boolean.");
		}
		} catch (NameNotFoundException e) {
		// This is expected when the package has not defined the property in its manifest.
		}

		// The package has not specified the property. The behavior depends on the package's
		// targetSdk.
		// <36 gets the old behavior of always using restricted mode.
		if (!CompatChanges.isChangeEnabled(OS_DECIDES_BACKUP_RESTRICTED_MODE, packageName,
		UserHandle.of(mUserId))) {
		return true;
		}

		// Apps targeting >=36 get the behavior decided by the transport.
		// By this point, we should have asked the transport and cached its decision.
		if ((mode == ApplicationThreadConstants.BACKUP_MODE_FULL
		&& mBackupNoRestrictedModePackages.contains(packageName)) \|\| (
		mode == ApplicationThreadConstants.BACKUP_MODE_RESTORE_FULL
		&& mRestoreNoRestrictedModePackages.contains(packageName))) {
		Slog.d(TAG, "Transport requested no restricted mode for: " + packageName);
		return false;
		}
		return true;
		}

		@VisibleForTesting
		Thread getThreadForCancellation(Runnable operation) {
		return new Thread(operation, /* operationName */ "agent-disconnected");
		}

		@VisibleForTesting
		int getCallingUid() {
		return Binder.getCallingUid();
		}
		}

services/backup/java/com/android/server/backup/BackupManagerService.java

+4 −2

Original line number	Diff line number	Diff line
		@@ -658,7 +658,8 @@ public class BackupManagerService extends IBackupManager.Stub {
		getServiceForUserIfCallerHasPermission(userId, "agentConnected()");

		if (userBackupManagerService != null) {
		userBackupManagerService.agentConnected(packageName, agentBinder);
		userBackupManagerService.getBackupAgentConnectionManager().agentConnected(packageName,
		agentBinder);
		}
		}

		@@ -683,7 +684,8 @@ public class BackupManagerService extends IBackupManager.Stub {
		getServiceForUserIfCallerHasPermission(userId, "agentDisconnected()");

		if (userBackupManagerService != null) {
		userBackupManagerService.agentDisconnected(packageName);
		userBackupManagerService.getBackupAgentConnectionManager().agentDisconnected(
		packageName);
		}
		}

services/backup/java/com/android/server/backup/KeyValueAdbBackupEngine.java

+2 −1

Original line number	Diff line number	Diff line
		@@ -146,7 +146,8 @@ public class KeyValueAdbBackupEngine {

		private IBackupAgent bindToAgent(ApplicationInfo targetApp) {
		try {
		return mBackupManagerService.bindToAgentSynchronous(targetApp,
		return mBackupManagerService.getBackupAgentConnectionManager().bindToAgentSynchronous(
		targetApp,
		ApplicationThreadConstants.BACKUP_MODE_INCREMENTAL,
		BackupAnnotations.BackupDestination.CLOUD);
		} catch (SecurityException e) {

services/backup/java/com/android/server/backup/UserBackupManagerService.java

+9 −257

File changed.

Preview size limit exceeded, changes collapsed.

services/backup/java/com/android/server/backup/fullbackup/FullBackupEngine.java

+1 −1

Original line number	Diff line number	Diff line
		@@ -314,7 +314,7 @@ public class FullBackupEngine {
		Slog.d(TAG, "Binding to full backup agent : " + mPkg.packageName);
		}
		mAgent =
		backupManagerService.bindToAgentSynchronous(
		backupManagerService.getBackupAgentConnectionManager().bindToAgentSynchronous(
		mPkg.applicationInfo, ApplicationThreadConstants.BACKUP_MODE_FULL,
		mBackupEligibilityRules.getBackupDestination());
		}