User Manager service to manage users and query user details

Moved a bunch of methods from PackageManager to UserManager.

Fix launching of activities from recents to correct user.

Guest creation APIs

Change-Id: I0733405e6eb2829675665e225c759d6baa2b708f
diff --git a/services/java/com/android/server/pm/UserManagerService.java b/services/java/com/android/server/pm/UserManagerService.java
new file mode 100644
index 0000000..b55dd24
--- /dev/null
+++ b/services/java/com/android/server/pm/UserManagerService.java
@@ -0,0 +1,615 @@
+/*
+ * Copyright (C) 2011 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.pm;
+
+import static android.os.ParcelFileDescriptor.MODE_CREATE;
+import static android.os.ParcelFileDescriptor.MODE_READ_WRITE;
+
+import com.android.internal.util.ArrayUtils;
+import com.android.internal.util.FastXmlSerializer;
+
+import android.content.Context;
+import android.content.Intent;
+import android.content.pm.ApplicationInfo;
+import android.content.pm.PackageManager;
+import android.content.pm.UserInfo;
+import android.os.Binder;
+import android.os.Environment;
+import android.os.FileUtils;
+import android.os.IUserManager;
+import android.os.ParcelFileDescriptor;
+import android.os.Process;
+import android.os.SystemClock;
+import android.os.UserId;
+import android.util.Log;
+import android.util.Slog;
+import android.util.SparseArray;
+import android.util.Xml;
+
+import java.io.BufferedOutputStream;
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.List;
+
+import org.xmlpull.v1.XmlPullParser;
+import org.xmlpull.v1.XmlPullParserException;
+import org.xmlpull.v1.XmlSerializer;
+
+public class UserManagerService extends IUserManager.Stub {
+
+    private static final String TAG = "UserManagerService";
+
+    private static final String TAG_NAME = "name";
+
+    private static final String ATTR_FLAGS = "flags";
+
+    private static final String ATTR_ICON_PATH = "icon";
+
+    private static final String ATTR_ID = "id";
+
+    private static final String TAG_USERS = "users";
+
+    private static final String TAG_USER = "user";
+
+    private static final String LOG_TAG = "UserManager";
+
+    private static final String USER_INFO_DIR = "system" + File.separator + "users";
+    private static final String USER_LIST_FILENAME = "userlist.xml";
+    private static final String USER_PHOTO_FILENAME = "photo.png";
+
+    private SparseArray<UserInfo> mUsers = new SparseArray<UserInfo>();
+
+    private final File mUsersDir;
+    private final File mUserListFile;
+    private int[] mUserIds;
+    private boolean mGuestEnabled;
+
+    private Installer mInstaller;
+    private File mBaseUserPath;
+    private Context mContext;
+    private static UserManagerService sInstance;
+    private PackageManagerService mPm;
+
+    public synchronized static UserManagerService getInstance(Context context) {
+        if (sInstance == null) {
+            sInstance = new UserManagerService(context);
+        }
+        return sInstance;
+    }
+
+    /**
+     * Available for testing purposes.
+     */
+    UserManagerService(File dataDir, File baseUserPath) {
+        mUsersDir = new File(dataDir, USER_INFO_DIR);
+        mUsersDir.mkdirs();
+        // Make zeroth user directory, for services to migrate their files to that location
+        File userZeroDir = new File(mUsersDir, "0");
+        userZeroDir.mkdirs();
+        mBaseUserPath = baseUserPath;
+        FileUtils.setPermissions(mUsersDir.toString(),
+                FileUtils.S_IRWXU|FileUtils.S_IRWXG
+                |FileUtils.S_IROTH|FileUtils.S_IXOTH,
+                -1, -1);
+        mUserListFile = new File(mUsersDir, USER_LIST_FILENAME);
+        readUserList();
+    }
+
+    public UserManagerService(Context context) {
+        this(Environment.getDataDirectory(), new File(Environment.getDataDirectory(), "user"));
+        mContext = context;
+    }
+
+    void setInstaller(PackageManagerService pm, Installer installer) {
+        mInstaller = installer;
+        mPm = pm;
+    }
+
+    @Override
+    public List<UserInfo> getUsers() {
+        enforceSystemOrRoot("Only the system can query users");
+        synchronized (mUsers) {
+            ArrayList<UserInfo> users = new ArrayList<UserInfo>(mUsers.size());
+            for (int i = 0; i < mUsers.size(); i++) {
+                users.add(mUsers.valueAt(i));
+            }
+            return users;
+        }
+    }
+
+    @Override
+    public UserInfo getUserInfo(int userId) {
+        enforceSystemOrRoot("Only the system can query user");
+        synchronized (mUsers) {
+            UserInfo info = mUsers.get(userId);
+            return info;
+        }
+    }
+
+    public boolean exists(int userId) {
+        synchronized (mUsers) {
+            return ArrayUtils.contains(mUserIds, userId);
+        }
+    }
+
+    @Override
+    public void setUserName(int userId, String name) {
+        enforceSystemOrRoot("Only the system can rename users");
+        synchronized (mUsers) {
+            UserInfo info = mUsers.get(userId);
+            if (name != null && !name.equals(info.name)) {
+                info.name = name;
+                writeUserLocked(info);
+            }
+        }
+    }
+
+    @Override
+    public ParcelFileDescriptor setUserIcon(int userId) {
+        enforceSystemOrRoot("Only the system can update users");
+        synchronized (mUsers) {
+            UserInfo info = mUsers.get(userId);
+            if (info == null) return null;
+            ParcelFileDescriptor fd = updateIconBitmapLocked(info);
+            if (fd != null) {
+                writeUserLocked(info);
+            }
+            return fd;
+        }
+    }
+
+    @Override
+    public void setGuestEnabled(boolean enable) {
+        enforceSystemOrRoot("Only the system can enable guest users");
+        synchronized (mUsers) {
+            if (mGuestEnabled != enable) {
+                mGuestEnabled = enable;
+                // Erase any guest user that currently exists
+                for (int i = 0; i < mUsers.size(); i++) {
+                    UserInfo user = mUsers.valueAt(i);
+                    if (user.isGuest()) {
+                        if (!enable) {
+                            removeUser(user.id);
+                        }
+                        return;
+                    }
+                }
+                // No guest was found
+                if (enable) {
+                    createUser("Guest", UserInfo.FLAG_GUEST);
+                }
+            }
+        }
+    }
+
+    @Override
+    public boolean isGuestEnabled() {
+        synchronized (mUsers) {
+            return mGuestEnabled;
+        }
+    }
+
+    @Override
+    public void wipeUser(int userHandle) {
+        enforceSystemOrRoot("Only the system can wipe users");
+        // TODO:
+    }
+
+    /**
+     * Enforces that only the system UID or root's UID can call a method exposed
+     * via Binder.
+     *
+     * @param message used as message if SecurityException is thrown
+     * @throws SecurityException if the caller is not system or root
+     */
+    private static final void enforceSystemOrRoot(String message) {
+        final int uid = Binder.getCallingUid();
+        if (uid != Process.SYSTEM_UID && uid != 0) {
+            throw new SecurityException(message);
+        }
+    }
+
+    private ParcelFileDescriptor updateIconBitmapLocked(UserInfo info) {
+        try {
+            File dir = new File(mUsersDir, Integer.toString(info.id));
+            File file = new File(dir, USER_PHOTO_FILENAME);
+            if (!dir.exists()) {
+                dir.mkdir();
+                FileUtils.setPermissions(
+                        dir.getPath(),
+                        FileUtils.S_IRWXU|FileUtils.S_IRWXG|FileUtils.S_IXOTH,
+                        -1, -1);
+            }
+            ParcelFileDescriptor fd = ParcelFileDescriptor.open(file,
+                    MODE_CREATE|MODE_READ_WRITE);
+            info.iconPath = file.getAbsolutePath();
+            return fd;
+        } catch (FileNotFoundException e) {
+            Slog.w(TAG, "Error setting photo for user ", e);
+        }
+        return null;
+    }
+
+    /**
+     * Returns an array of user ids. This array is cached here for quick access, so do not modify or
+     * cache it elsewhere.
+     * @return the array of user ids.
+     */
+    int[] getUserIds() {
+        return mUserIds;
+    }
+
+    private void readUserList() {
+        synchronized (mUsers) {
+            readUserListLocked();
+        }
+    }
+
+    private void readUserListLocked() {
+        mGuestEnabled = false;
+        if (!mUserListFile.exists()) {
+            fallbackToSingleUserLocked();
+            return;
+        }
+        FileInputStream fis = null;
+        try {
+            fis = new FileInputStream(mUserListFile);
+            XmlPullParser parser = Xml.newPullParser();
+            parser.setInput(fis, null);
+            int type;
+            while ((type = parser.next()) != XmlPullParser.START_TAG
+                    && type != XmlPullParser.END_DOCUMENT) {
+                ;
+            }
+
+            if (type != XmlPullParser.START_TAG) {
+                Slog.e(LOG_TAG, "Unable to read user list");
+                fallbackToSingleUserLocked();
+                return;
+            }
+
+            while ((type = parser.next()) != XmlPullParser.END_DOCUMENT) {
+                if (type == XmlPullParser.START_TAG && parser.getName().equals(TAG_USER)) {
+                    String id = parser.getAttributeValue(null, ATTR_ID);
+                    UserInfo user = readUser(Integer.parseInt(id));
+                    if (user != null) {
+                        mUsers.put(user.id, user);
+                    }
+                    if (user.isGuest()) {
+                        mGuestEnabled = true;
+                    }
+                }
+            }
+            updateUserIdsLocked();
+        } catch (IOException ioe) {
+            fallbackToSingleUserLocked();
+        } catch (XmlPullParserException pe) {
+            fallbackToSingleUserLocked();
+        } finally {
+            if (fis != null) {
+                try {
+                    fis.close();
+                } catch (IOException e) {
+                }
+            }
+        }
+    }
+
+    private void fallbackToSingleUserLocked() {
+        // Create the primary user
+        UserInfo primary = new UserInfo(0, "Primary", null,
+                UserInfo.FLAG_ADMIN | UserInfo.FLAG_PRIMARY);
+        mUsers.put(0, primary);
+        updateUserIdsLocked();
+
+        writeUserListLocked();
+        writeUserLocked(primary);
+    }
+
+    /*
+     * Writes the user file in this format:
+     *
+     * <user flags="20039023" id="0">
+     *   <name>Primary</name>
+     * </user>
+     */
+    private void writeUserLocked(UserInfo userInfo) {
+        FileOutputStream fos = null;
+        try {
+            final File mUserFile = new File(mUsersDir, userInfo.id + ".xml");
+            fos = new FileOutputStream(mUserFile);
+            final BufferedOutputStream bos = new BufferedOutputStream(fos);
+
+            // XmlSerializer serializer = XmlUtils.serializerInstance();
+            final XmlSerializer serializer = new FastXmlSerializer();
+            serializer.setOutput(bos, "utf-8");
+            serializer.startDocument(null, true);
+            serializer.setFeature("http://xmlpull.org/v1/doc/features.html#indent-output", true);
+
+            serializer.startTag(null, TAG_USER);
+            serializer.attribute(null, ATTR_ID, Integer.toString(userInfo.id));
+            serializer.attribute(null, ATTR_FLAGS, Integer.toString(userInfo.flags));
+            if (userInfo.iconPath != null) {
+                serializer.attribute(null,  ATTR_ICON_PATH, userInfo.iconPath);
+            }
+
+            serializer.startTag(null, TAG_NAME);
+            serializer.text(userInfo.name);
+            serializer.endTag(null, TAG_NAME);
+
+            serializer.endTag(null, TAG_USER);
+
+            serializer.endDocument();
+        } catch (IOException ioe) {
+            Slog.e(LOG_TAG, "Error writing user info " + userInfo.id + "\n" + ioe);
+        } finally {
+            if (fos != null) {
+                try {
+                    fos.close();
+                } catch (IOException ioe) {
+                }
+            }
+        }
+    }
+
+    /*
+     * Writes the user list file in this format:
+     *
+     * <users>
+     *   <user id="0"></user>
+     *   <user id="2"></user>
+     * </users>
+     */
+    private void writeUserListLocked() {
+        FileOutputStream fos = null;
+        try {
+            fos = new FileOutputStream(mUserListFile);
+            final BufferedOutputStream bos = new BufferedOutputStream(fos);
+
+            // XmlSerializer serializer = XmlUtils.serializerInstance();
+            final XmlSerializer serializer = new FastXmlSerializer();
+            serializer.setOutput(bos, "utf-8");
+            serializer.startDocument(null, true);
+            serializer.setFeature("http://xmlpull.org/v1/doc/features.html#indent-output", true);
+
+            serializer.startTag(null, TAG_USERS);
+
+            for (int i = 0; i < mUsers.size(); i++) {
+                UserInfo user = mUsers.valueAt(i);
+                serializer.startTag(null, TAG_USER);
+                serializer.attribute(null, ATTR_ID, Integer.toString(user.id));
+                serializer.endTag(null, TAG_USER);
+            }
+
+            serializer.endTag(null, TAG_USERS);
+
+            serializer.endDocument();
+        } catch (IOException ioe) {
+            Slog.e(LOG_TAG, "Error writing user list");
+        } finally {
+            if (fos != null) {
+                try {
+                    fos.close();
+                } catch (IOException ioe) {
+                }
+            }
+        }
+    }
+
+    private UserInfo readUser(int id) {
+        int flags = 0;
+        String name = null;
+        String iconPath = null;
+
+        FileInputStream fis = null;
+        try {
+            File userFile = new File(mUsersDir, Integer.toString(id) + ".xml");
+            fis = new FileInputStream(userFile);
+            XmlPullParser parser = Xml.newPullParser();
+            parser.setInput(fis, null);
+            int type;
+            while ((type = parser.next()) != XmlPullParser.START_TAG
+                    && type != XmlPullParser.END_DOCUMENT) {
+                ;
+            }
+
+            if (type != XmlPullParser.START_TAG) {
+                Slog.e(LOG_TAG, "Unable to read user " + id);
+                return null;
+            }
+
+            if (type == XmlPullParser.START_TAG && parser.getName().equals(TAG_USER)) {
+                String storedId = parser.getAttributeValue(null, ATTR_ID);
+                if (Integer.parseInt(storedId) != id) {
+                    Slog.e(LOG_TAG, "User id does not match the file name");
+                    return null;
+                }
+                String flagString = parser.getAttributeValue(null, ATTR_FLAGS);
+                flags = Integer.parseInt(flagString);
+                iconPath = parser.getAttributeValue(null, ATTR_ICON_PATH);
+
+                while ((type = parser.next()) != XmlPullParser.START_TAG
+                        && type != XmlPullParser.END_DOCUMENT) {
+                }
+                if (type == XmlPullParser.START_TAG && parser.getName().equals(TAG_NAME)) {
+                    type = parser.next();
+                    if (type == XmlPullParser.TEXT) {
+                        name = parser.getText();
+                    }
+                }
+            }
+
+            UserInfo userInfo = new UserInfo(id, name, iconPath, flags);
+            return userInfo;
+
+        } catch (IOException ioe) {
+        } catch (XmlPullParserException pe) {
+        } finally {
+            if (fis != null) {
+                try {
+                    fis.close();
+                } catch (IOException e) {
+                }
+            }
+        }
+        return null;
+    }
+
+    @Override
+    public UserInfo createUser(String name, int flags) {
+        enforceSystemOrRoot("Only the system can create users");
+        int userId = getNextAvailableId();
+        UserInfo userInfo = new UserInfo(userId, name, null, flags);
+        File userPath = new File(mBaseUserPath, Integer.toString(userId));
+        if (!createPackageFolders(userId, userPath)) {
+            return null;
+        }
+        synchronized (mUsers) {
+            mUsers.put(userId, userInfo);
+            writeUserListLocked();
+            writeUserLocked(userInfo);
+            updateUserIdsLocked();
+        }
+        if (userInfo != null) {
+            Intent addedIntent = new Intent(Intent.ACTION_USER_ADDED);
+            addedIntent.putExtra(Intent.EXTRA_USERID, userInfo.id);
+            mContext.sendBroadcast(addedIntent, android.Manifest.permission.MANAGE_ACCOUNTS);
+        }
+        return userInfo;
+    }
+
+    /**
+     * Removes a user and all data directories created for that user. This method should be called
+     * after the user's processes have been terminated.
+     * @param id the user's id
+     */
+    public boolean removeUser(int userHandle) {
+        enforceSystemOrRoot("Only the system can remove users");
+        synchronized (mUsers) {
+            return removeUserLocked(userHandle);
+        }
+    }
+
+    private boolean removeUserLocked(int userHandle) {
+        final UserInfo user = mUsers.get(userHandle);
+        if (userHandle == 0 || user == null) {
+            return false;
+        }
+
+        mPm.cleanUpUser(userHandle);
+
+        // Remove this user from the list
+        mUsers.remove(userHandle);
+        // Remove user file
+        File userFile = new File(mUsersDir, userHandle + ".xml");
+        userFile.delete();
+        // Update the user list
+        writeUserListLocked();
+        updateUserIdsLocked();
+
+        // Let other services shutdown any activity
+        Intent addedIntent = new Intent(Intent.ACTION_USER_REMOVED);
+        addedIntent.putExtra(Intent.EXTRA_USERID, userHandle);
+        mContext.sendBroadcast(addedIntent, android.Manifest.permission.MANAGE_ACCOUNTS);
+
+        removePackageFolders(userHandle);
+        return true;
+    }
+
+    public void installPackageForAllUsers(String packageName, int uid) {
+        for (int userId : mUserIds) {
+            // Don't do it for the primary user, it will become recursive.
+            if (userId == 0)
+                continue;
+            mInstaller.createUserData(packageName, UserId.getUid(userId, uid),
+                    userId);
+        }
+    }
+
+    public void clearUserDataForAllUsers(String packageName) {
+        for (int userId : mUserIds) {
+            // Don't do it for the primary user, it will become recursive.
+            if (userId == 0)
+                continue;
+            mInstaller.clearUserData(packageName, userId);
+        }
+    }
+
+    public void removePackageForAllUsers(String packageName) {
+        for (int userId : mUserIds) {
+            // Don't do it for the primary user, it will become recursive.
+            if (userId == 0)
+                continue;
+            mInstaller.remove(packageName, userId);
+        }
+    }
+
+    /**
+     * Caches the list of user ids in an array, adjusting the array size when necessary.
+     */
+    private void updateUserIdsLocked() {
+        if (mUserIds == null || mUserIds.length != mUsers.size()) {
+            mUserIds = new int[mUsers.size()];
+        }
+        for (int i = 0; i < mUsers.size(); i++) {
+            mUserIds[i] = mUsers.keyAt(i);
+        }
+    }
+
+    /**
+     * Returns the next available user id, filling in any holes in the ids.
+     * TODO: May not be a good idea to recycle ids, in case it results in confusion
+     * for data and battery stats collection, or unexpected cross-talk.
+     * @return
+     */
+    private int getNextAvailableId() {
+        int i = 0;
+        while (i < Integer.MAX_VALUE) {
+            if (mUsers.indexOfKey(i) < 0) {
+                break;
+            }
+            i++;
+        }
+        return i;
+    }
+
+    private boolean createPackageFolders(int id, File userPath) {
+        // mInstaller may not be available for unit-tests.
+        if (mInstaller == null) return true;
+
+        // Create the user path
+        userPath.mkdir();
+        FileUtils.setPermissions(userPath.toString(), FileUtils.S_IRWXU | FileUtils.S_IRWXG
+                | FileUtils.S_IXOTH, -1, -1);
+
+        mInstaller.cloneUserData(0, id, false);
+
+        return true;
+    }
+
+    boolean removePackageFolders(int id) {
+        // mInstaller may not be available for unit-tests.
+        if (mInstaller == null) return true;
+
+        mInstaller.removeUserDataDirs(id);
+        return true;
+    }
+}