/*
* Copyright (C) 2012 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.content.ContentResolver;
import android.content.ContentValues;
import android.content.Context;
import android.content.pm.PackageManager;
import android.content.pm.UserInfo;
import static android.content.Context.USER_SERVICE;
import static android.Manifest.permission.READ_PROFILE;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.os.Binder;
import android.os.Environment;
import android.os.RemoteException;
import android.os.SystemProperties;
import android.os.UserHandle;
import android.os.UserManager;
import android.provider.Settings;
import android.provider.Settings.Secure;
import android.provider.Settings.SettingNotFoundException;
import android.text.TextUtils;
import android.util.Slog;
import com.android.internal.widget.ILockSettings;
import com.android.internal.widget.LockPatternUtils;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.RandomAccessFile;
import java.util.Arrays;
import java.util.List;
/**
* Keeps the lock pattern/password data and related settings for each user.
* Used by LockPatternUtils. Needs to be a service because Settings app also needs
* to be able to save lockscreen information for secondary users.
* @hide
*/
public class LockSettingsService extends ILockSettings.Stub {
private final DatabaseHelper mOpenHelper;
private static final String TAG = "LockSettingsService";
private static final String TABLE = "locksettings";
private static final String COLUMN_KEY = "name";
private static final String COLUMN_USERID = "user";
private static final String COLUMN_VALUE = "value";
private static final String[] COLUMNS_FOR_QUERY = {
COLUMN_VALUE
};
private static final String SYSTEM_DIRECTORY = "/system/";
private static final String LOCK_PATTERN_FILE = "gesture.key";
private static final String LOCK_PASSWORD_FILE = "password.key";
private final Context mContext;
public LockSettingsService(Context context) {
mContext = context;
// Open the database
mOpenHelper = new DatabaseHelper(mContext);
}
public void systemReady() {
migrateOldData();
}
private void migrateOldData() {
try {
// These Settings moved before multi-user was enabled, so we only have to do it for the
// root user.
if (getString("migrated", null, 0) == null) {
final ContentResolver cr = mContext.getContentResolver();
for (String validSetting : VALID_SETTINGS) {
String value = Settings.Secure.getString(cr, validSetting);
if (value != null) {
setString(validSetting, value, 0);
}
}
// No need to move the password / pattern files. They're already in the right place.
setString("migrated", "true", 0);
Slog.i(TAG, "Migrated lock settings to new location");
}
// These Settings changed after multi-user was enabled, hence need to be moved per user.
if (getString("migrated_user_specific", null, 0) == null) {
final UserManager um = (UserManager) mContext.getSystemService(USER_SERVICE);
final ContentResolver cr = mContext.getContentResolver();
List<UserInfo> users = um.getUsers();
for (int user = 0; user < users.size(); user++) {
// Migrate owner info
final int userId = users.get(user).id;
final String OWNER_INFO = Secure.LOCK_SCREEN_OWNER_INFO;
String ownerInfo = Settings.Secure.getStringForUser(cr, OWNER_INFO, userId);
if (ownerInfo != null) {
setString(OWNER_INFO, ownerInfo, userId);
Settings.Secure.putStringForUser(cr, ownerInfo, "", userId);
}
// Migrate owner info enabled. Note there was a bug where older platforms only
// stored this value if the checkbox was toggled at least once. The code detects
// this case by handling the exception.
final String OWNER_INFO_ENABLED = Secure.LOCK_SCREEN_OWNER_INFO_ENABLED;
boolean enabled;
try {
int ivalue = Settings.Secure.getIntForUser(cr, OWNER_INFO_ENABLED, userId);
enabled = ivalue != 0;
setLong(OWNER_INFO_ENABLED, enabled ? 1 : 0, userId);
} catch (SettingNotFoundException e) {
// Setting was never stored. Store it if the string is not empty.
if (!TextUtils.isEmpty(ownerInfo)) {
setLong(OWNER_INFO_ENABLED, 1, userId);
}
}
Settings.Secure.putIntForUser(cr, OWNER_INFO_ENABLED, 0, userId);
}
// No need to move the password / pattern files. They're already in the right place.
setString("migrated_user_specific", "true", 0);
Slog.i(TAG, "Migrated per-user lock settings to new location");
}
} catch (RemoteException re) {
Slog.e(TAG, "Unable to migrate old data", re);
}
}
private static final void checkWritePermission(int userId) {
final int callingUid = Binder.getCallingUid();
if (UserHandle.getAppId(callingUid) != android.os.Process.SYSTEM_UID) {
throw new SecurityException("uid=" + callingUid
+ " not authorized to write lock settings");
}
}
private static final void checkPasswordReadPermission(int userId) {
final int callingUid = Binder.getCallingUid();
if (UserHandle.getAppId(callingUid) != android.os.Process.SYSTEM_UID) {
throw new SecurityException("uid=" + callingUid
+ " not authorized to read lock password");
}
}
private final void checkReadPermission(String requestedKey, int userId) {
final int callingUid = Binder.getCallingUid();
for (int i = 0; i < READ_PROFILE_PROTECTED_SETTINGS.length; i++) {
String key = READ_PROFILE_PROTECTED_SETTINGS[i];
if (key.equals(requestedKey) && mContext.checkCallingOrSelfPermission(READ_PROFILE)
!= PackageManager.PERMISSION_GRANTED) {
throw new SecurityException("uid=" + callingUid
+ " needs permission " + READ_PROFILE + " to read "
+ requestedKey + " for user " + userId);
}
}
}
@Override
public void setBoolean(String key, boolean value, int userId) throws RemoteException {
checkWritePermission(userId);
writeToDb(key, value ? "1" : "0", userId);
}
@Override
public void setLong(String key, long value, int userId) throws RemoteException {
checkWritePermission(userId);
writeToDb(key, Long.toString(value), userId);
}
@Override
public void setString(String key, String value, int userId) throws RemoteException {
checkWritePermission(userId);
writeToDb(key, value, userId);
}
@Override
public boolean getBoolean(String key, boolean defaultValue, int userId) throws RemoteException {
checkReadPermission(key, userId);
String value = readFromDb(key, null, userId);
return TextUtils.isEmpty(value) ?
defaultValue : (value.equals("1") || value.equals("true"));
}
@Override
public long getLong(String key, long defaultValue, int userId) throws RemoteException {
checkReadPermission(key, userId);
String value = readFromDb(key, null, userId);
return TextUtils.isEmpty(value) ? defaultValue : Long.parseLong(value);
}
@Override
public String getString(String key, String defaultValue, int userId) throws RemoteException {
checkReadPermission(key, userId);
return readFromDb(key, defaultValue, userId);
}
private String getLockPatternFilename(int userId) {
String dataSystemDirectory =
android.os.Environment.getDataDirectory().getAbsolutePath() +
SYSTEM_DIRECTORY;
if (userId == 0) {
// Leave it in the same place for user 0
return dataSystemDirectory + LOCK_PATTERN_FILE;
} else {
return new File(Environment.getUserSystemDirectory(userId), LOCK_PATTERN_FILE)
.getAbsolutePath();
}
}
private String getLockPasswordFilename(int userId) {
String dataSystemDirectory =
android.os.Environment.getDataDirectory().getAbsolutePath() +
SYSTEM_DIRECTORY;
if (userId == 0) {
// Leave it in the same place for user 0
return dataSystemDirectory + LOCK_PASSWORD_FILE;
} else {
return new File(Environment.getUserSystemDirectory(userId), LOCK_PASSWORD_FILE)
.getAbsolutePath();
}
}
@Override
public boolean havePassword(int userId) throws RemoteException {
// Do we need a permissions check here?
return new File(getLockPasswordFilename(userId)).length() > 0;
}
@Override
public boolean havePattern(int userId) throws RemoteException {
// Do we need a permissions check here?
return new File(getLockPatternFilename(userId)).length() > 0;
}
@Override
public void setLockPattern(byte[] hash, int userId) throws RemoteException {
checkWritePermission(userId);
writeFile(getLockPatternFilename(userId), hash);
}
@Override
public boolean checkPattern(byte[] hash, int userId) throws RemoteException {
checkPasswordReadPermission(userId);
try {
// Read all the bytes from the file
RandomAccessFile raf = new RandomAccessFile(getLockPatternFilename(userId), "r");
final byte[] stored = new byte[(int) raf.length()];
int got = raf.read(stored, 0, stored.length);
raf.close();
if (got <= 0) {
return true;
}
// Compare the hash from the file with the entered pattern's hash
return Arrays.equals(stored, hash);
} catch (FileNotFoundException fnfe) {
Slog.e(TAG, "Cannot read file " + fnfe);
return true;
} catch (IOException ioe) {
Slog.e(TAG, "Cannot read file " + ioe);
return true;
}
}
@Override
public void setLockPassword(byte[] hash, int userId) throws RemoteException {
checkWritePermission(userId);
writeFile(getLockPasswordFilename(userId), hash);
}
@Override
public boolean checkPassword(byte[] hash, int userId) throws RemoteException {
checkPasswordReadPermission(userId);
try {
// Read all the bytes from the file
RandomAccessFile raf = new RandomAccessFile(getLockPasswordFilename(userId), "r");
final byte[] stored = new byte[(int) raf.length()];
int got = raf.read(stored, 0, stored.length);
raf.close();
if (got <= 0) {
return true;
}
// Compare the hash from the file with the entered password's hash
return Arrays.equals(stored, hash);
} catch (FileNotFoundException fnfe) {
Slog.e(TAG, "Cannot read file " + fnfe);
return true;
} catch (IOException ioe) {
Slog.e(TAG, "Cannot read file " + ioe);
return true;
}
}
@Override
public void removeUser(int userId) {
checkWritePermission(userId);
SQLiteDatabase db = mOpenHelper.getWritableDatabase();
try {
File file = new File(getLockPasswordFilename(userId));
if (file.exists()) {
file.delete();
}
file = new File(getLockPatternFilename(userId));
if (file.exists()) {
file.delete();
}
db.beginTransaction();
db.delete(TABLE, COLUMN_USERID + "='" + userId + "'", null);
db.setTransactionSuccessful();
} finally {
db.endTransaction();
}
}
private void writeFile(String name, byte[] hash) {
try {
// Write the hash to file
RandomAccessFile raf = new RandomAccessFile(name, "rw");
// Truncate the file if pattern is null, to clear the lock
if (hash == null || hash.length == 0) {
raf.setLength(0);
} else {
raf.write(hash, 0, hash.length);
}
raf.close();
} catch (IOException ioe) {
Slog.e(TAG, "Error writing to file " + ioe);
}
}
private void writeToDb(String key, String value, int userId) {
writeToDb(mOpenHelper.getWritableDatabase(), key, value, userId);
}
private void writeToDb(SQLiteDatabase db, String key, String value, int userId) {
ContentValues cv = new ContentValues();
cv.put(COLUMN_KEY, key);
cv.put(COLUMN_USERID, userId);
cv.put(COLUMN_VALUE, value);
db.beginTransaction();
try {
db.delete(TABLE, COLUMN_KEY + "=? AND " + COLUMN_USERID + "=?",
new String[] {key, Integer.toString(userId)});
db.insert(TABLE, null, cv);
db.setTransactionSuccessful();
} finally {
db.endTransaction();
}
}
private String readFromDb(String key, String defaultValue, int userId) {
Cursor cursor;
String result = defaultValue;
SQLiteDatabase db = mOpenHelper.getReadableDatabase();
if ((cursor = db.query(TABLE, COLUMNS_FOR_QUERY,
COLUMN_USERID + "=? AND " + COLUMN_KEY + "=?",
new String[] { Integer.toString(userId), key },
null, null, null)) != null) {
if (cursor.moveToFirst()) {
result = cursor.getString(0);
}
cursor.close();
}
return result;
}
class DatabaseHelper extends SQLiteOpenHelper {
private static final String TAG = "LockSettingsDB";
private static final String DATABASE_NAME = "locksettings.db";
private static final int DATABASE_VERSION = 1;
public DatabaseHelper(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
setWriteAheadLoggingEnabled(true);
}
private void createTable(SQLiteDatabase db) {
db.execSQL("CREATE TABLE " + TABLE + " (" +
"_id INTEGER PRIMARY KEY AUTOINCREMENT," +
COLUMN_KEY + " TEXT," +
COLUMN_USERID + " INTEGER," +
COLUMN_VALUE + " TEXT" +
");");
}
@Override
public void onCreate(SQLiteDatabase db) {
createTable(db);
initializeDefaults(db);
}
private void initializeDefaults(SQLiteDatabase db) {
// Get the lockscreen default from a system property, if available
boolean lockScreenDisable = SystemProperties.getBoolean("ro.lockscreen.disable.default",
false);
if (lockScreenDisable) {
writeToDb(db, LockPatternUtils.DISABLE_LOCKSCREEN_KEY, "1", 0);
}
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int currentVersion) {
// Nothing yet
}
}
private static final String[] VALID_SETTINGS = new String[] {
LockPatternUtils.LOCKOUT_PERMANENT_KEY,
LockPatternUtils.LOCKOUT_ATTEMPT_DEADLINE,
LockPatternUtils.PATTERN_EVER_CHOSEN_KEY,
LockPatternUtils.PASSWORD_TYPE_KEY,
LockPatternUtils.PASSWORD_TYPE_ALTERNATE_KEY,
LockPatternUtils.LOCK_PASSWORD_SALT_KEY,
LockPatternUtils.DISABLE_LOCKSCREEN_KEY,
LockPatternUtils.LOCKSCREEN_OPTIONS,
LockPatternUtils.LOCKSCREEN_BIOMETRIC_WEAK_FALLBACK,
LockPatternUtils.BIOMETRIC_WEAK_EVER_CHOSEN_KEY,
LockPatternUtils.LOCKSCREEN_POWER_BUTTON_INSTANTLY_LOCKS,
LockPatternUtils.PASSWORD_HISTORY_KEY,
Secure.LOCK_PATTERN_ENABLED,
Secure.LOCK_BIOMETRIC_WEAK_FLAGS,
Secure.LOCK_PATTERN_VISIBLE,
Secure.LOCK_PATTERN_TACTILE_FEEDBACK_ENABLED
};
// These are protected with a read permission
private static final String[] READ_PROFILE_PROTECTED_SETTINGS = new String[] {
Secure.LOCK_SCREEN_OWNER_INFO_ENABLED,
Secure.LOCK_SCREEN_OWNER_INFO
};
}