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/*
* Copyright (C) 2009 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;
import android.app.ActivityManagerNative;
import android.app.IActivityManager;
import android.app.IApplicationThread;
import android.app.IBackupAgent;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.content.pm.ApplicationInfo;
import android.content.pm.PackageInfo;
import android.content.pm.PackageManager;
import android.content.pm.PackageManager.NameNotFoundException;
import android.net.Uri;
import android.os.Binder;
import android.os.Bundle;
import android.os.Environment;
import android.os.Handler;
import android.os.IBinder;
import android.os.Message;
import android.os.ParcelFileDescriptor;
import android.os.Process;
import android.os.RemoteException;
import android.util.Log;
import android.util.SparseArray;
import android.backup.IBackupManager;
import android.backup.BackupManager;
import com.android.internal.backup.AdbTransport;
import com.android.internal.backup.GoogleTransport;
import com.android.internal.backup.IBackupTransport;
import java.io.File;
import java.io.FileDescriptor;
import java.io.FileNotFoundException;
import java.io.PrintWriter;
import java.lang.String;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
class BackupManagerService extends IBackupManager.Stub {
private static final String TAG = "BackupManagerService";
private static final boolean DEBUG = true;
private static final long COLLECTION_INTERVAL = 1000;
//private static final long COLLECTION_INTERVAL = 3 * 60 * 1000;
private static final int MSG_RUN_BACKUP = 1;
private static final int MSG_RUN_FULL_BACKUP = 2;
private Context mContext;
private PackageManager mPackageManager;
private final IActivityManager mActivityManager;
private final BackupHandler mBackupHandler = new BackupHandler();
// map UIDs to the set of backup client services within that UID's app set
private SparseArray<HashSet<ApplicationInfo>> mBackupParticipants
= new SparseArray<HashSet<ApplicationInfo>>();
// set of backup services that have pending changes
private class BackupRequest {
public ApplicationInfo appInfo;
public boolean fullBackup;
BackupRequest(ApplicationInfo app, boolean isFull) {
appInfo = app;
fullBackup = isFull;
}
public String toString() {
return "BackupRequest{app=" + appInfo + " full=" + fullBackup + "}";
}
}
// Backups that we haven't started yet.
private HashMap<ApplicationInfo,BackupRequest> mPendingBackups
= new HashMap<ApplicationInfo,BackupRequest>();
// Backups that we have started. These are separate to prevent starvation
// if an app keeps re-enqueuing itself.
private ArrayList<BackupRequest> mBackupQueue;
private final Object mQueueLock = new Object();
// 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 int mTransportId;
private File mStateDir;
private File mDataDir;
public BackupManagerService(Context context) {
mContext = context;
mPackageManager = context.getPackageManager();
mActivityManager = ActivityManagerNative.getDefault();
// Set up our bookkeeping
mStateDir = new File(Environment.getDataDirectory(), "backup");
mStateDir.mkdirs();
mDataDir = Environment.getDownloadCacheDirectory();
mTransportId = BackupManager.TRANSPORT_GOOGLE;
// Build our mapping of uid to backup client services
synchronized (mBackupParticipants) {
addPackageParticipantsLocked(null);
}
// Register for broadcasts about package install, etc., so we can
// update the provider list.
IntentFilter filter = new IntentFilter();
filter.addAction(Intent.ACTION_PACKAGE_ADDED);
filter.addAction(Intent.ACTION_PACKAGE_REMOVED);
filter.addDataScheme("package");
mContext.registerReceiver(mBroadcastReceiver, filter);
}
// ----- Track installation/removal of packages -----
BroadcastReceiver mBroadcastReceiver = new BroadcastReceiver() {
public void onReceive(Context context, Intent intent) {
if (DEBUG) Log.d(TAG, "Received broadcast " + intent);
Uri uri = intent.getData();
if (uri == null) {
return;
}
String pkgName = uri.getSchemeSpecificPart();
if (pkgName == null) {
return;
}
String action = intent.getAction();
if (Intent.ACTION_PACKAGE_ADDED.equals(action)) {
synchronized (mBackupParticipants) {
Bundle extras = intent.getExtras();
if (extras != null && extras.getBoolean(Intent.EXTRA_REPLACING, false)) {
// The package was just upgraded
updatePackageParticipantsLocked(pkgName);
} else {
// The package was just added
addPackageParticipantsLocked(pkgName);
}
}
}
else if (Intent.ACTION_PACKAGE_REMOVED.equals(action)) {
Bundle extras = intent.getExtras();
if (extras != null && extras.getBoolean(Intent.EXTRA_REPLACING, false)) {
// The package is being updated. We'll receive a PACKAGE_ADDED shortly.
} else {
synchronized (mBackupParticipants) {
removePackageParticipantsLocked(pkgName);
}
}
}
}
};
// ----- Run the actual backup process asynchronously -----
private class BackupHandler extends Handler {
public void handleMessage(Message msg) {
switch (msg.what) {
case MSG_RUN_BACKUP:
// snapshot the pending-backup set and work on that
synchronized (mQueueLock) {
if (mBackupQueue == null) {
mBackupQueue = new ArrayList<BackupRequest>();
for (BackupRequest b: mPendingBackups.values()) {
mBackupQueue.add(b);
}
mPendingBackups = new HashMap<ApplicationInfo,BackupRequest>();
}
// !!! TODO: start a new backup-queue journal file too
// WARNING: If we crash after this line, anything in mPendingBackups will
// be lost. FIX THIS.
}
(new PerformBackupThread(mTransportId, mBackupQueue)).run();
break;
case MSG_RUN_FULL_BACKUP:
break;
}
}
}
void processOneBackup(BackupRequest request, IBackupAgent agent, IBackupTransport transport) {
final String packageName = request.appInfo.packageName;
Log.d(TAG, "processOneBackup doBackup() on " + packageName);
try {
// Look up the package info & signatures. This is first so that if it
// throws an exception, there's no file setup yet that would need to
// be unraveled.
PackageInfo packInfo = mPackageManager.getPackageInfo(packageName, PackageManager.GET_SIGNATURES);
// !!! TODO: get the state file dir from the transport
File savedStateName = new File(mStateDir, packageName);
File backupDataName = new File(mDataDir, packageName + ".data");
File newStateName = new File(mStateDir, packageName + ".new");
// In a full backup, we pass a null ParcelFileDescriptor as
// the saved-state "file"
ParcelFileDescriptor savedState = (request.fullBackup) ? null
: ParcelFileDescriptor.open(savedStateName,
ParcelFileDescriptor.MODE_READ_ONLY |
ParcelFileDescriptor.MODE_CREATE);
backupDataName.delete();
ParcelFileDescriptor backupData =
ParcelFileDescriptor.open(backupDataName,
ParcelFileDescriptor.MODE_READ_WRITE |
ParcelFileDescriptor.MODE_CREATE);
newStateName.delete();
ParcelFileDescriptor newState =
ParcelFileDescriptor.open(newStateName,
ParcelFileDescriptor.MODE_READ_WRITE |
ParcelFileDescriptor.MODE_CREATE);
// Run the target's backup pass
boolean success = false;
try {
agent.doBackup(savedState, backupData, newState);
success = true;
} finally {
if (savedState != null) {
savedState.close();
}
backupData.close();
newState.close();
}
// Now propagate the newly-backed-up data to the transport
if (success) {
if (DEBUG) Log.v(TAG, "doBackup() success; calling transport");
backupData =
ParcelFileDescriptor.open(backupDataName, ParcelFileDescriptor.MODE_READ_ONLY);
int error = transport.performBackup(packInfo, backupData);
// !!! TODO: After successful transport, delete the now-stale data
// and juggle the files so that next time the new state is passed
//backupDataName.delete();
newStateName.renameTo(savedStateName);
}
} catch (NameNotFoundException e) {
Log.e(TAG, "Package not found on backup: " + packageName);
} catch (FileNotFoundException fnf) {
Log.w(TAG, "File not found on backup: ");
fnf.printStackTrace();
} catch (RemoteException e) {
Log.d(TAG, "Remote target " + request.appInfo.packageName + " threw during backup:");
e.printStackTrace();
} catch (Exception e) {
Log.w(TAG, "Final exception guard in backup: ");
e.printStackTrace();
}
}
// Add the backup agents in the given package to our set of known backup participants.
// If 'packageName' is null, adds all backup agents in the whole system.
void addPackageParticipantsLocked(String packageName) {
// Look for apps that define the android:backupAgent attribute
if (DEBUG) Log.v(TAG, "addPackageParticipantsLocked: " + packageName);
List<ApplicationInfo> targetApps = allAgentApps();
addPackageParticipantsLockedInner(packageName, targetApps);
}
private void addPackageParticipantsLockedInner(String packageName,
List<ApplicationInfo> targetApps) {
if (DEBUG) {
Log.v(TAG, "Adding " + targetApps.size() + " backup participants:");
for (ApplicationInfo a : targetApps) {
Log.v(TAG, " " + a + " agent=" + a.backupAgentName);
}
}
for (ApplicationInfo app : targetApps) {
if (packageName == null || app.packageName.equals(packageName)) {
int uid = app.uid;
HashSet<ApplicationInfo> set = mBackupParticipants.get(uid);
if (set == null) {
set = new HashSet<ApplicationInfo>();
mBackupParticipants.put(uid, set);
}
set.add(app);
}
}
}
// Remove the given package's backup services from our known active set. If
// 'packageName' is null, *all* backup services will be removed.
void removePackageParticipantsLocked(String packageName) {
if (DEBUG) Log.v(TAG, "removePackageParticipantsLocked: " + packageName);
List<ApplicationInfo> allApps = null;
if (packageName != null) {
allApps = new ArrayList<ApplicationInfo>();
try {
ApplicationInfo app = mPackageManager.getApplicationInfo(packageName, 0);
allApps.add(app);
} catch (Exception e) {
// just skip it
}
} else {
// all apps with agents
allApps = allAgentApps();
}
removePackageParticipantsLockedInner(packageName, allApps);
}
private void removePackageParticipantsLockedInner(String packageName,
List<ApplicationInfo> agents) {
if (DEBUG) {
Log.v(TAG, "removePackageParticipantsLockedInner (" + packageName
+ ") removing " + agents.size() + " entries");
for (ApplicationInfo a : agents) {
Log.v(TAG, " - " + a);
}
}
for (ApplicationInfo app : agents) {
if (packageName == null || app.packageName.equals(packageName)) {
int uid = app.uid;
HashSet<ApplicationInfo> set = mBackupParticipants.get(uid);
if (set != null) {
// Find the existing entry with the same package name, and remove it.
// We can't just remove(app) because the instances are different.
for (ApplicationInfo entry: set) {
if (entry.packageName.equals(app.packageName)) {
set.remove(entry);
break;
}
}
if (set.size() == 0) {
mBackupParticipants.delete(uid); }
}
}
}
}
// Returns the set of all applications that define an android:backupAgent attribute
private List<ApplicationInfo> allAgentApps() {
List<ApplicationInfo> allApps = mPackageManager.getInstalledApplications(0);
int N = allApps.size();
if (N > 0) {
for (int a = N-1; a >= 0; a--) {
ApplicationInfo app = allApps.get(a);
if (app.backupAgentName == null) {
allApps.remove(a);
}
}
}
return allApps;
}
// Reset the given package's known backup participants. Unlike add/remove, the update
// action cannot be passed a null package name.
void updatePackageParticipantsLocked(String packageName) {
if (packageName == null) {
Log.e(TAG, "updatePackageParticipants called with null package name");
return;
}
if (DEBUG) Log.v(TAG, "updatePackageParticipantsLocked: " + packageName);
// brute force but small code size
List<ApplicationInfo> allApps = allAgentApps();
removePackageParticipantsLockedInner(packageName, allApps);
addPackageParticipantsLockedInner(packageName, allApps);
}
// ----- Back up a set of applications via a worker thread -----
class PerformBackupThread extends Thread {
private static final String TAG = "PerformBackupThread";
int mTransport;
ArrayList<BackupRequest> mQueue;
public PerformBackupThread(int transportId, ArrayList<BackupRequest> queue) {
mTransport = transportId;
mQueue = queue;
}
@Override
public void run() {
/*
* 1. start up the current transport
* 2. for each item in the queue:
* 2a. bind the agent [wait for async attach]
* 2b. set up the files and call doBackup()
* 2c. unbind the agent
* 3. tear down the transport
* 4. done!
*/
if (DEBUG) Log.v(TAG, "Beginning backup of " + mQueue.size() + " targets");
// stand up the current transport
IBackupTransport transport = null;
switch (mTransport) {
case BackupManager.TRANSPORT_ADB:
if (DEBUG) Log.v(TAG, "Initializing adb transport");
transport = new AdbTransport();
break;
case BackupManager.TRANSPORT_GOOGLE:
if (DEBUG) Log.v(TAG, "Initializing Google transport");
//!!! TODO: stand up the google backup transport here
transport = new GoogleTransport();
break;
default:
Log.e(TAG, "Perform backup with unknown transport " + mTransport);
// !!! TODO: re-enqueue the backup queue for later?
return;
}
try {
transport.startSession();
} catch (Exception e) {
Log.e(TAG, "Error starting backup session");
e.printStackTrace();
// !!! TODO: re-enqueue the backup queue for later?
return;
}
// The transport is up and running; now run all the backups in our queue
doQueuedBackups(transport);
// Finally, tear down the transport
try {
transport.endSession();
} catch (Exception e) {
Log.e(TAG, "Error ending transport");
e.printStackTrace();
}
}
private void doQueuedBackups(IBackupTransport transport) {
for (BackupRequest request : mQueue) {
Log.d(TAG, "starting agent for " + request);
// !!! TODO: need to handle the restore case?
IBackupAgent agent = null;
int mode = (request.fullBackup)
? IApplicationThread.BACKUP_MODE_FULL
: IApplicationThread.BACKUP_MODE_INCREMENTAL;
try {
synchronized(mAgentConnectLock) {
mConnecting = true;
mConnectedAgent = null;
if (mActivityManager.bindBackupAgent(request.appInfo, mode)) {
Log.d(TAG, "awaiting agent for " + request);
// success; wait for the agent to arrive
while (mConnecting && mConnectedAgent == null) {
try {
mAgentConnectLock.wait(10000);
} catch (InterruptedException e) {
// just retry
continue;
}
}
// if we timed out with no connect, abort and move on
if (mConnecting == true) {
Log.w(TAG, "Timeout waiting for agent " + request);
continue;
}
agent = mConnectedAgent;
}
}
} catch (RemoteException e) {
// can't happen; activity manager is local
} catch (SecurityException ex) {
// Try for the next one.
Log.d(TAG, "error in bind", ex);
}
// successful bind? run the backup for this agent
if (agent != null) {
processOneBackup(request, agent, transport);
}
// send the unbind even on timeout, just in case
try {
mActivityManager.unbindBackupAgent(request.appInfo);
} catch (RemoteException e) {
// can't happen
}
}
}
}
// ----- IBackupManager binder interface -----
public void dataChanged(String packageName) throws RemoteException {
// Record that we need a backup pass for the caller. Since multiple callers
// may share a uid, we need to note all candidates within that uid and schedule
// a backup pass for each of them.
Log.d(TAG, "dataChanged packageName=" + packageName);
HashSet<ApplicationInfo> targets = mBackupParticipants.get(Binder.getCallingUid());
if (targets != null) {
synchronized (mQueueLock) {
// Note that this client has made data changes that need to be backed up
for (ApplicationInfo app : targets) {
// validate the caller-supplied package name against the known set of
// packages associated with this uid
if (app.packageName.equals(packageName)) {
// Add the caller to the set of pending backups. If there is
// one already there, then overwrite it, but no harm done.
BackupRequest req = new BackupRequest(app, false);
mPendingBackups.put(app, req);
// !!! TODO: write to the pending-backup journal file in case of crash
}
}
if (DEBUG) {
int numKeys = mPendingBackups.size();
Log.d(TAG, "Scheduling backup for " + numKeys + " participants:");
for (BackupRequest b : mPendingBackups.values()) {
Log.d(TAG, " + " + b + " agent=" + b.appInfo.backupAgentName);
}
}
// Schedule a backup pass in a few minutes. As backup-eligible data
// keeps changing, continue to defer the backup pass until things
// settle down, to avoid extra overhead.
mBackupHandler.removeMessages(MSG_RUN_BACKUP);
mBackupHandler.sendEmptyMessageDelayed(MSG_RUN_BACKUP, COLLECTION_INTERVAL);
}
}
}
// Schedule a backup pass for a given package. This method will schedule a
// full backup even for apps that do not declare an android:backupAgent, so
// use with care.
public void scheduleFullBackup(String packageName) throws RemoteException {
mContext.enforceCallingPermission("android.permission.BACKUP", "scheduleFullBackup");
if (DEBUG) Log.v(TAG, "Scheduling immediate full backup for " + packageName);
synchronized (mQueueLock) {
try {
ApplicationInfo app = mPackageManager.getApplicationInfo(packageName, 0);
mPendingBackups.put(app, new BackupRequest(app, true));
mBackupHandler.sendEmptyMessage(MSG_RUN_FULL_BACKUP);
} catch (NameNotFoundException e) {
Log.w(TAG, "Could not find app for " + packageName + " to schedule full backup");
}
}
}
// Select which transport to use for the next backup operation
public int selectBackupTransport(int transportId) {
mContext.enforceCallingPermission("android.permission.BACKUP", "selectBackupTransport");
int prevTransport = mTransportId;
mTransportId = transportId;
return prevTransport;
}
// Callback: a requested backup agent has been instantiated. This should only
// be called from the Activity Manager.
public void agentConnected(String packageName, IBinder agentBinder) {
synchronized(mAgentConnectLock) {
if (Binder.getCallingUid() == Process.SYSTEM_UID) {
Log.d(TAG, "agentConnected pkg=" + packageName + " agent=" + agentBinder);
IBackupAgent agent = IBackupAgent.Stub.asInterface(agentBinder);
mConnectedAgent = agent;
mConnecting = false;
} else {
Log.w(TAG, "Non-system process uid=" + Binder.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 null. This should only be called from the Activity Manager.
public void agentDisconnected(String packageName) {
// TODO: handle backup being interrupted
synchronized(mAgentConnectLock) {
if (Binder.getCallingUid() == Process.SYSTEM_UID) {
mConnectedAgent = null;
mConnecting = false;
} else {
Log.w(TAG, "Non-system process uid=" + Binder.getCallingUid()
+ " claiming agent disconnected");
}
mAgentConnectLock.notifyAll();
}
}
@Override
public void dump(FileDescriptor fd, PrintWriter pw, String[] args) {
synchronized (mQueueLock) {
int N = mBackupParticipants.size();
pw.println("Participants:");
for (int i=0; i<N; i++) {
int uid = mBackupParticipants.keyAt(i);
pw.print(" uid: ");
pw.println(uid);
HashSet<ApplicationInfo> participants = mBackupParticipants.valueAt(i);
for (ApplicationInfo app: participants) {
pw.print(" ");
pw.println(app.toString());
}
}
pw.println("Pending:");
Iterator<BackupRequest> br = mPendingBackups.values().iterator();
while (br.hasNext()) {
pw.print(" ");
pw.println(br);
}
}
}
}
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