| /* |
| * 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.slice; |
| |
| import static android.content.ContentProvider.getUriWithoutUserId; |
| import static android.content.ContentProvider.getUserIdFromUri; |
| import static android.content.ContentProvider.maybeAddUserId; |
| import static android.content.pm.PackageManager.PERMISSION_DENIED; |
| import static android.content.pm.PackageManager.PERMISSION_GRANTED; |
| import static android.os.Process.SYSTEM_UID; |
| |
| import android.Manifest.permission; |
| import android.app.ActivityManager; |
| import android.app.AppOpsManager; |
| import android.app.ContentProviderHolder; |
| import android.app.IActivityManager; |
| import android.app.slice.ISliceListener; |
| import android.app.slice.ISliceManager; |
| import android.app.slice.SliceManager; |
| import android.app.slice.SliceSpec; |
| import android.content.BroadcastReceiver; |
| import android.content.ComponentName; |
| import android.content.Context; |
| import android.content.Intent; |
| import android.content.IntentFilter; |
| import android.content.pm.PackageManagerInternal; |
| import android.content.pm.ResolveInfo; |
| import android.database.ContentObserver; |
| import android.net.Uri; |
| import android.os.Binder; |
| import android.os.Environment; |
| import android.os.Handler; |
| import android.os.IBinder; |
| import android.os.Looper; |
| import android.os.Process; |
| import android.os.RemoteException; |
| import android.os.UserHandle; |
| import android.util.ArrayMap; |
| import android.util.ArraySet; |
| import android.util.AtomicFile; |
| import android.util.Log; |
| import android.util.Slog; |
| import android.util.Xml.Encoding; |
| |
| import com.android.internal.annotations.GuardedBy; |
| import com.android.internal.annotations.VisibleForTesting; |
| import com.android.internal.app.AssistUtils; |
| import com.android.internal.util.Preconditions; |
| import com.android.server.LocalServices; |
| import com.android.server.ServiceThread; |
| import com.android.server.SystemService; |
| |
| import org.xmlpull.v1.XmlPullParser; |
| import org.xmlpull.v1.XmlPullParserException; |
| import org.xmlpull.v1.XmlPullParserFactory; |
| import org.xmlpull.v1.XmlSerializer; |
| |
| import java.io.ByteArrayInputStream; |
| import java.io.ByteArrayOutputStream; |
| import java.io.File; |
| import java.io.FileOutputStream; |
| import java.io.IOException; |
| import java.io.InputStream; |
| import java.util.ArrayList; |
| import java.util.List; |
| import java.util.Objects; |
| |
| public class SliceManagerService extends ISliceManager.Stub { |
| |
| private static final String TAG = "SliceManagerService"; |
| private final Object mLock = new Object(); |
| |
| private final Context mContext; |
| private final PackageManagerInternal mPackageManagerInternal; |
| private final AppOpsManager mAppOps; |
| private final AssistUtils mAssistUtils; |
| |
| @GuardedBy("mLock") |
| private final ArrayMap<Uri, PinnedSliceState> mPinnedSlicesByUri = new ArrayMap<>(); |
| @GuardedBy("mLock") |
| private final ArraySet<SliceGrant> mUserGrants = new ArraySet<>(); |
| private final Handler mHandler; |
| private final ContentObserver mObserver; |
| @GuardedBy("mSliceAccessFile") |
| private final AtomicFile mSliceAccessFile; |
| @GuardedBy("mAccessList") |
| private final SliceFullAccessList mAccessList; |
| |
| public SliceManagerService(Context context) { |
| this(context, createHandler().getLooper()); |
| } |
| |
| @VisibleForTesting |
| SliceManagerService(Context context, Looper looper) { |
| mContext = context; |
| mPackageManagerInternal = Preconditions.checkNotNull( |
| LocalServices.getService(PackageManagerInternal.class)); |
| mAppOps = context.getSystemService(AppOpsManager.class); |
| mAssistUtils = new AssistUtils(context); |
| mHandler = new Handler(looper); |
| |
| mObserver = new ContentObserver(mHandler) { |
| @Override |
| public void onChange(boolean selfChange, Uri uri, int userId) { |
| try { |
| getPinnedSlice(maybeAddUserId(uri, userId)).onChange(); |
| } catch (IllegalStateException e) { |
| Log.e(TAG, "Received change for unpinned slice " + uri, e); |
| } |
| } |
| }; |
| final File systemDir = new File(Environment.getDataDirectory(), "system"); |
| mSliceAccessFile = new AtomicFile(new File(systemDir, "slice_access.xml")); |
| mAccessList = new SliceFullAccessList(mContext); |
| |
| synchronized (mSliceAccessFile) { |
| if (!mSliceAccessFile.exists()) return; |
| try { |
| InputStream input = mSliceAccessFile.openRead(); |
| XmlPullParser parser = XmlPullParserFactory.newInstance().newPullParser(); |
| parser.setInput(input, Encoding.UTF_8.name()); |
| synchronized (mAccessList) { |
| mAccessList.readXml(parser); |
| } |
| } catch (IOException | XmlPullParserException e) { |
| Slog.d(TAG, "Can't read slice access file", e); |
| } |
| } |
| |
| IntentFilter filter = new IntentFilter(); |
| filter.addAction(Intent.ACTION_PACKAGE_DATA_CLEARED); |
| filter.addAction(Intent.ACTION_PACKAGE_REMOVED); |
| filter.addDataScheme("package"); |
| mContext.registerReceiverAsUser(mReceiver, UserHandle.ALL, filter, null, mHandler); |
| } |
| |
| /// ----- Lifecycle stuff ----- |
| private void systemReady() { |
| } |
| |
| private void onUnlockUser(int userId) { |
| } |
| |
| private void onStopUser(int userId) { |
| synchronized (mLock) { |
| mPinnedSlicesByUri.values().removeIf(s -> getUserIdFromUri(s.getUri()) == userId); |
| } |
| } |
| |
| /// ----- ISliceManager stuff ----- |
| @Override |
| public void addSliceListener(Uri uri, String pkg, ISliceListener listener, SliceSpec[] specs) |
| throws RemoteException { |
| verifyCaller(pkg); |
| uri = maybeAddUserId(uri, Binder.getCallingUserHandle().getIdentifier()); |
| enforceCrossUser(pkg, uri); |
| getOrCreatePinnedSlice(uri).addSliceListener(listener, pkg, specs, |
| checkAccess(pkg, uri, Binder.getCallingUid(), Binder.getCallingUid()) |
| == PERMISSION_GRANTED); |
| } |
| |
| @Override |
| public void removeSliceListener(Uri uri, String pkg, ISliceListener listener) |
| throws RemoteException { |
| verifyCaller(pkg); |
| uri = maybeAddUserId(uri, Binder.getCallingUserHandle().getIdentifier()); |
| if (getPinnedSlice(uri).removeSliceListener(listener)) { |
| removePinnedSlice(uri); |
| } |
| } |
| |
| @Override |
| public void pinSlice(String pkg, Uri uri, SliceSpec[] specs) throws RemoteException { |
| verifyCaller(pkg); |
| enforceFullAccess(pkg, "pinSlice", uri); |
| uri = maybeAddUserId(uri, Binder.getCallingUserHandle().getIdentifier()); |
| getOrCreatePinnedSlice(uri).pin(pkg, specs); |
| } |
| |
| @Override |
| public void unpinSlice(String pkg, Uri uri) throws RemoteException { |
| verifyCaller(pkg); |
| enforceFullAccess(pkg, "unpinSlice", uri); |
| uri = maybeAddUserId(uri, Binder.getCallingUserHandle().getIdentifier()); |
| if (getPinnedSlice(uri).unpin(pkg)) { |
| removePinnedSlice(uri); |
| } |
| } |
| |
| @Override |
| public boolean hasSliceAccess(String pkg) throws RemoteException { |
| verifyCaller(pkg); |
| return hasFullSliceAccess(pkg, Binder.getCallingUserHandle().getIdentifier()); |
| } |
| |
| @Override |
| public SliceSpec[] getPinnedSpecs(Uri uri, String pkg) throws RemoteException { |
| verifyCaller(pkg); |
| enforceAccess(pkg, uri); |
| return getPinnedSlice(uri).getSpecs(); |
| } |
| |
| @Override |
| public int checkSlicePermission(Uri uri, String pkg, int pid, int uid) throws RemoteException { |
| if (mContext.checkUriPermission(uri, pid, uid, Intent.FLAG_GRANT_WRITE_URI_PERMISSION) |
| == PERMISSION_GRANTED) { |
| return SliceManager.PERMISSION_GRANTED; |
| } |
| if (hasFullSliceAccess(pkg, UserHandle.getUserId(uid))) { |
| return SliceManager.PERMISSION_GRANTED; |
| } |
| synchronized (mLock) { |
| if (mUserGrants.contains(new SliceGrant(uri, pkg, UserHandle.getUserId(uid)))) { |
| return SliceManager.PERMISSION_USER_GRANTED; |
| } |
| } |
| return SliceManager.PERMISSION_DENIED; |
| } |
| |
| @Override |
| public void grantPermissionFromUser(Uri uri, String pkg, String callingPkg, boolean allSlices) { |
| verifyCaller(callingPkg); |
| getContext().enforceCallingOrSelfPermission(permission.MANAGE_SLICE_PERMISSIONS, |
| "Slice granting requires MANAGE_SLICE_PERMISSIONS"); |
| if (allSlices) { |
| synchronized (mAccessList) { |
| mAccessList.grantFullAccess(pkg, Binder.getCallingUserHandle().getIdentifier()); |
| } |
| mHandler.post(mSaveAccessList); |
| } else { |
| synchronized (mLock) { |
| mUserGrants.add(new SliceGrant(uri, pkg, |
| Binder.getCallingUserHandle().getIdentifier())); |
| } |
| } |
| long ident = Binder.clearCallingIdentity(); |
| try { |
| mContext.getContentResolver().notifyChange(uri, null); |
| } finally { |
| Binder.restoreCallingIdentity(ident); |
| } |
| synchronized (mLock) { |
| for (PinnedSliceState p : mPinnedSlicesByUri.values()) { |
| p.recheckPackage(pkg); |
| } |
| } |
| } |
| |
| // Backup/restore interface |
| @Override |
| public byte[] getBackupPayload(int user) { |
| if (Binder.getCallingUid() != SYSTEM_UID) { |
| throw new SecurityException("Caller must be system"); |
| } |
| //TODO: http://b/22388012 |
| if (user != UserHandle.USER_SYSTEM) { |
| Slog.w(TAG, "getBackupPayload: cannot backup policy for user " + user); |
| return null; |
| } |
| synchronized(mSliceAccessFile) { |
| final ByteArrayOutputStream baos = new ByteArrayOutputStream(); |
| try { |
| XmlSerializer out = XmlPullParserFactory.newInstance().newSerializer(); |
| out.setOutput(baos, Encoding.UTF_8.name()); |
| synchronized (mAccessList) { |
| mAccessList.writeXml(out, user); |
| } |
| out.flush(); |
| return baos.toByteArray(); |
| } catch (IOException | XmlPullParserException e) { |
| Slog.w(TAG, "getBackupPayload: error writing payload for user " + user, e); |
| } |
| } |
| return null; |
| } |
| |
| @Override |
| public void applyRestore(byte[] payload, int user) { |
| if (Binder.getCallingUid() != SYSTEM_UID) { |
| throw new SecurityException("Caller must be system"); |
| } |
| if (payload == null) { |
| Slog.w(TAG, "applyRestore: no payload to restore for user " + user); |
| return; |
| } |
| //TODO: http://b/22388012 |
| if (user != UserHandle.USER_SYSTEM) { |
| Slog.w(TAG, "applyRestore: cannot restore policy for user " + user); |
| return; |
| } |
| synchronized(mSliceAccessFile) { |
| final ByteArrayInputStream bais = new ByteArrayInputStream(payload); |
| try { |
| XmlPullParser parser = XmlPullParserFactory.newInstance().newPullParser(); |
| parser.setInput(bais, Encoding.UTF_8.name()); |
| synchronized (mAccessList) { |
| mAccessList.readXml(parser); |
| } |
| mHandler.post(mSaveAccessList); |
| } catch (NumberFormatException | XmlPullParserException | IOException e) { |
| Slog.w(TAG, "applyRestore: error reading payload", e); |
| } |
| } |
| } |
| |
| /// ----- internal code ----- |
| private void removeFullAccess(String pkg, int userId) { |
| synchronized (mAccessList) { |
| mAccessList.removeGrant(pkg, userId); |
| } |
| mHandler.post(mSaveAccessList); |
| } |
| |
| protected void removePinnedSlice(Uri uri) { |
| synchronized (mLock) { |
| mPinnedSlicesByUri.remove(uri).destroy(); |
| } |
| } |
| |
| private PinnedSliceState getPinnedSlice(Uri uri) { |
| synchronized (mLock) { |
| PinnedSliceState manager = mPinnedSlicesByUri.get(uri); |
| if (manager == null) { |
| throw new IllegalStateException(String.format("Slice %s not pinned", |
| uri.toString())); |
| } |
| return manager; |
| } |
| } |
| |
| private PinnedSliceState getOrCreatePinnedSlice(Uri uri) { |
| synchronized (mLock) { |
| PinnedSliceState manager = mPinnedSlicesByUri.get(uri); |
| if (manager == null) { |
| manager = createPinnedSlice(uri); |
| mPinnedSlicesByUri.put(uri, manager); |
| } |
| return manager; |
| } |
| } |
| |
| @VisibleForTesting |
| protected PinnedSliceState createPinnedSlice(Uri uri) { |
| return new PinnedSliceState(this, uri); |
| } |
| |
| public Object getLock() { |
| return mLock; |
| } |
| |
| public Context getContext() { |
| return mContext; |
| } |
| |
| public Handler getHandler() { |
| return mHandler; |
| } |
| |
| protected int checkAccess(String pkg, Uri uri, int uid, int pid) { |
| int user = UserHandle.getUserId(uid); |
| // Check for default launcher/assistant. |
| if (!hasFullSliceAccess(pkg, user)) { |
| // Also allow things with uri access. |
| if (getContext().checkUriPermission(uri, pid, uid, |
| Intent.FLAG_GRANT_WRITE_URI_PERMISSION) != PERMISSION_GRANTED) { |
| // Last fallback (if the calling app owns the authority, then it can have access). |
| long ident = Binder.clearCallingIdentity(); |
| try { |
| IBinder token = new Binder(); |
| IActivityManager activityManager = ActivityManager.getService(); |
| ContentProviderHolder holder = null; |
| String providerName = getUriWithoutUserId(uri).getAuthority(); |
| try { |
| try { |
| holder = activityManager.getContentProviderExternal( |
| providerName, getUserIdFromUri(uri, user), token); |
| if (holder == null || holder.info == null |
| || !Objects.equals(holder.info.packageName, pkg)) { |
| return PERMISSION_DENIED; |
| } |
| } finally { |
| if (holder != null && holder.provider != null) { |
| activityManager.removeContentProviderExternal(providerName, token); |
| } |
| } |
| } catch (RemoteException e) { |
| // Can't happen. |
| e.rethrowAsRuntimeException(); |
| } |
| } finally { |
| // I know, the double finally seems ugly, but seems safest for the identity. |
| Binder.restoreCallingIdentity(ident); |
| } |
| } |
| } |
| return PERMISSION_GRANTED; |
| } |
| |
| private void enforceCrossUser(String pkg, Uri uri) { |
| int user = Binder.getCallingUserHandle().getIdentifier(); |
| if (getUserIdFromUri(uri, user) != user) { |
| getContext().enforceCallingOrSelfPermission(permission.INTERACT_ACROSS_USERS_FULL, |
| "Slice interaction across users requires INTERACT_ACROSS_USERS_FULL"); |
| } |
| } |
| |
| private void enforceAccess(String pkg, Uri uri) throws RemoteException { |
| if (checkAccess(pkg, uri, Binder.getCallingUid(), Binder.getCallingPid()) |
| != PERMISSION_GRANTED) { |
| throw new SecurityException("Access to slice " + uri + " is required"); |
| } |
| enforceCrossUser(pkg, uri); |
| } |
| |
| private void enforceFullAccess(String pkg, String name, Uri uri) { |
| int user = Binder.getCallingUserHandle().getIdentifier(); |
| if (!hasFullSliceAccess(pkg, user)) { |
| throw new SecurityException(String.format("Call %s requires full slice access", name)); |
| } |
| enforceCrossUser(pkg, uri); |
| } |
| |
| private void verifyCaller(String pkg) { |
| mAppOps.checkPackage(Binder.getCallingUid(), pkg); |
| } |
| |
| private boolean hasFullSliceAccess(String pkg, int userId) { |
| long ident = Binder.clearCallingIdentity(); |
| try { |
| boolean ret = isDefaultHomeApp(pkg, userId) || isAssistant(pkg, userId) |
| || isGrantedFullAccess(pkg, userId); |
| return ret; |
| } finally { |
| Binder.restoreCallingIdentity(ident); |
| } |
| } |
| |
| private boolean isAssistant(String pkg, int userId) { |
| final ComponentName cn = mAssistUtils.getAssistComponentForUser(userId); |
| if (cn == null) { |
| return false; |
| } |
| return cn.getPackageName().equals(pkg); |
| } |
| |
| public void listen(Uri uri) { |
| mContext.getContentResolver().registerContentObserver(uri, true, mObserver); |
| } |
| |
| public void unlisten(Uri uri) { |
| mContext.getContentResolver().unregisterContentObserver(mObserver); |
| synchronized (mLock) { |
| mPinnedSlicesByUri.forEach((u, s) -> { |
| if (s.isListening()) { |
| listen(u); |
| } |
| }); |
| } |
| } |
| |
| private boolean isDefaultHomeApp(String pkg, int userId) { |
| String defaultHome = getDefaultHome(userId); |
| |
| return pkg != null && Objects.equals(pkg, defaultHome); |
| } |
| |
| // Based on getDefaultHome in ShortcutService. |
| // TODO: Unify if possible |
| @VisibleForTesting |
| protected String getDefaultHome(int userId) { |
| final long token = Binder.clearCallingIdentity(); |
| try { |
| final List<ResolveInfo> allHomeCandidates = new ArrayList<>(); |
| |
| // Default launcher from package manager. |
| final ComponentName defaultLauncher = mPackageManagerInternal |
| .getHomeActivitiesAsUser(allHomeCandidates, userId); |
| |
| ComponentName detected = null; |
| if (defaultLauncher != null) { |
| detected = defaultLauncher; |
| } |
| |
| if (detected == null) { |
| // If we reach here, that means it's the first check since the user was created, |
| // and there's already multiple launchers and there's no default set. |
| // Find the system one with the highest priority. |
| // (We need to check the priority too because of FallbackHome in Settings.) |
| // If there's no system launcher yet, then no one can access slices, until |
| // the user explicitly sets one. |
| final int size = allHomeCandidates.size(); |
| |
| int lastPriority = Integer.MIN_VALUE; |
| for (int i = 0; i < size; i++) { |
| final ResolveInfo ri = allHomeCandidates.get(i); |
| if (!ri.activityInfo.applicationInfo.isSystemApp()) { |
| continue; |
| } |
| if (ri.priority < lastPriority) { |
| continue; |
| } |
| detected = ri.activityInfo.getComponentName(); |
| lastPriority = ri.priority; |
| } |
| } |
| return detected != null ? detected.getPackageName() : null; |
| } finally { |
| Binder.restoreCallingIdentity(token); |
| } |
| } |
| |
| private boolean isGrantedFullAccess(String pkg, int userId) { |
| synchronized (mAccessList) { |
| return mAccessList.hasFullAccess(pkg, userId); |
| } |
| } |
| |
| private static ServiceThread createHandler() { |
| ServiceThread handlerThread = new ServiceThread(TAG, |
| Process.THREAD_PRIORITY_BACKGROUND, true /*allowIo*/); |
| handlerThread.start(); |
| return handlerThread; |
| } |
| |
| private final Runnable mSaveAccessList = new Runnable() { |
| @Override |
| public void run() { |
| synchronized (mSliceAccessFile) { |
| final FileOutputStream stream; |
| try { |
| stream = mSliceAccessFile.startWrite(); |
| } catch (IOException e) { |
| Slog.w(TAG, "Failed to save access file", e); |
| return; |
| } |
| |
| try { |
| XmlSerializer out = XmlPullParserFactory.newInstance().newSerializer(); |
| out.setOutput(stream, Encoding.UTF_8.name()); |
| synchronized (mAccessList) { |
| mAccessList.writeXml(out, UserHandle.USER_ALL); |
| } |
| out.flush(); |
| mSliceAccessFile.finishWrite(stream); |
| } catch (IOException | XmlPullParserException e) { |
| Slog.w(TAG, "Failed to save access file, restoring backup", e); |
| mSliceAccessFile.failWrite(stream); |
| } |
| } |
| } |
| }; |
| |
| private final BroadcastReceiver mReceiver = new BroadcastReceiver() { |
| @Override |
| public void onReceive(Context context, Intent intent) { |
| final int userId = intent.getIntExtra(Intent.EXTRA_USER_HANDLE, UserHandle.USER_NULL); |
| if (userId == UserHandle.USER_NULL) { |
| Slog.w(TAG, "Intent broadcast does not contain user handle: " + intent); |
| return; |
| } |
| Uri data = intent.getData(); |
| String pkg = data != null ? data.getSchemeSpecificPart() : null; |
| if (pkg == null) { |
| Slog.w(TAG, "Intent broadcast does not contain package name: " + intent); |
| return; |
| } |
| switch (intent.getAction()) { |
| case Intent.ACTION_PACKAGE_REMOVED: |
| final boolean replacing = |
| intent.getBooleanExtra(Intent.EXTRA_REPLACING, false); |
| if (!replacing) { |
| removeFullAccess(pkg, userId); |
| } |
| break; |
| case Intent.ACTION_PACKAGE_DATA_CLEARED: |
| removeFullAccess(pkg, userId); |
| break; |
| } |
| } |
| }; |
| |
| public static class Lifecycle extends SystemService { |
| private SliceManagerService mService; |
| |
| public Lifecycle(Context context) { |
| super(context); |
| } |
| |
| @Override |
| public void onStart() { |
| mService = new SliceManagerService(getContext()); |
| publishBinderService(Context.SLICE_SERVICE, mService); |
| } |
| |
| @Override |
| public void onBootPhase(int phase) { |
| if (phase == SystemService.PHASE_ACTIVITY_MANAGER_READY) { |
| mService.systemReady(); |
| } |
| } |
| |
| @Override |
| public void onUnlockUser(int userHandle) { |
| mService.onUnlockUser(userHandle); |
| } |
| |
| @Override |
| public void onStopUser(int userHandle) { |
| mService.onStopUser(userHandle); |
| } |
| } |
| |
| private class SliceGrant { |
| private final Uri mUri; |
| private final String mPkg; |
| private final int mUserId; |
| |
| public SliceGrant(Uri uri, String pkg, int userId) { |
| mUri = uri; |
| mPkg = pkg; |
| mUserId = userId; |
| } |
| |
| @Override |
| public int hashCode() { |
| return mUri.hashCode() + mPkg.hashCode(); |
| } |
| |
| @Override |
| public boolean equals(Object obj) { |
| if (!(obj instanceof SliceGrant)) return false; |
| SliceGrant other = (SliceGrant) obj; |
| return Objects.equals(other.mUri, mUri) && Objects.equals(other.mPkg, mPkg) |
| && (other.mUserId == mUserId); |
| } |
| } |
| } |