Sujith Ramakrishnan | b5b86c1 | 2016-01-28 16:53:16 -0800 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2016 The Android Open Source Project |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | |
| 17 | package com.android.server.tv; |
| 18 | |
| 19 | import android.Manifest; |
| 20 | import android.content.BroadcastReceiver; |
| 21 | import android.content.ComponentName; |
| 22 | import android.content.Context; |
| 23 | import android.content.Intent; |
| 24 | import android.content.IntentFilter; |
| 25 | import android.content.pm.PackageManager; |
| 26 | import android.content.pm.ResolveInfo; |
| 27 | import android.content.pm.ServiceInfo; |
| 28 | import android.os.Handler; |
| 29 | import android.os.UserHandle; |
| 30 | import android.util.Log; |
| 31 | import android.util.Slog; |
| 32 | |
Andrei Litvin | b298d4c | 2020-02-27 13:29:20 -0500 | [diff] [blame] | 33 | import com.android.internal.annotations.VisibleForTesting; |
| 34 | |
Sujith Ramakrishnan | b5b86c1 | 2016-01-28 16:53:16 -0800 | [diff] [blame] | 35 | import java.util.ArrayList; |
| 36 | import java.util.Collections; |
| 37 | |
| 38 | /** |
| 39 | * Watches for emote provider services to be installed. |
| 40 | * Adds a provider for each registered service. |
| 41 | * |
| 42 | * @see TvRemoteProviderProxy |
| 43 | */ |
| 44 | final class TvRemoteProviderWatcher { |
| 45 | |
Tom Macieszczak | 34ba4b1 | 2019-09-23 15:24:39 +0200 | [diff] [blame] | 46 | private static final String TAG = "TvRemoteProviderWatcher"; |
Sujith Ramakrishnan | b5b86c1 | 2016-01-28 16:53:16 -0800 | [diff] [blame] | 47 | private static final boolean DEBUG = Log.isLoggable(TAG, Log.VERBOSE); |
| 48 | |
| 49 | private final Context mContext; |
Sujith Ramakrishnan | b5b86c1 | 2016-01-28 16:53:16 -0800 | [diff] [blame] | 50 | private final Handler mHandler; |
| 51 | private final PackageManager mPackageManager; |
| 52 | private final ArrayList<TvRemoteProviderProxy> mProviderProxies = new ArrayList<>(); |
| 53 | private final int mUserId; |
| 54 | private final String mUnbundledServicePackage; |
Tom Macieszczak | 34ba4b1 | 2019-09-23 15:24:39 +0200 | [diff] [blame] | 55 | private final Object mLock; |
Sujith Ramakrishnan | b5b86c1 | 2016-01-28 16:53:16 -0800 | [diff] [blame] | 56 | |
| 57 | private boolean mRunning; |
| 58 | |
Tom Macieszczak | 34ba4b1 | 2019-09-23 15:24:39 +0200 | [diff] [blame] | 59 | TvRemoteProviderWatcher(Context context, Object lock) { |
Sujith Ramakrishnan | b5b86c1 | 2016-01-28 16:53:16 -0800 | [diff] [blame] | 60 | mContext = context; |
Tom Macieszczak | aee0bb2 | 2019-09-03 11:41:50 +0200 | [diff] [blame] | 61 | mHandler = new Handler(true); |
Sujith Ramakrishnan | b5b86c1 | 2016-01-28 16:53:16 -0800 | [diff] [blame] | 62 | mUserId = UserHandle.myUserId(); |
| 63 | mPackageManager = context.getPackageManager(); |
| 64 | mUnbundledServicePackage = context.getString( |
| 65 | com.android.internal.R.string.config_tvRemoteServicePackage); |
Tom Macieszczak | 34ba4b1 | 2019-09-23 15:24:39 +0200 | [diff] [blame] | 66 | mLock = lock; |
Sujith Ramakrishnan | b5b86c1 | 2016-01-28 16:53:16 -0800 | [diff] [blame] | 67 | } |
| 68 | |
| 69 | public void start() { |
| 70 | if (DEBUG) Slog.d(TAG, "start()"); |
| 71 | if (!mRunning) { |
| 72 | mRunning = true; |
| 73 | |
| 74 | IntentFilter filter = new IntentFilter(); |
| 75 | filter.addAction(Intent.ACTION_PACKAGE_ADDED); |
| 76 | filter.addAction(Intent.ACTION_PACKAGE_REMOVED); |
| 77 | filter.addAction(Intent.ACTION_PACKAGE_CHANGED); |
| 78 | filter.addAction(Intent.ACTION_PACKAGE_REPLACED); |
| 79 | filter.addAction(Intent.ACTION_PACKAGE_RESTARTED); |
| 80 | filter.addDataScheme("package"); |
| 81 | mContext.registerReceiverAsUser(mScanPackagesReceiver, |
| 82 | new UserHandle(mUserId), filter, null, mHandler); |
| 83 | |
| 84 | // Scan packages. |
| 85 | // Also has the side-effect of restarting providers if needed. |
| 86 | mHandler.post(mScanPackagesRunnable); |
| 87 | } |
| 88 | } |
| 89 | |
| 90 | public void stop() { |
| 91 | if (mRunning) { |
| 92 | mRunning = false; |
| 93 | |
| 94 | mContext.unregisterReceiver(mScanPackagesReceiver); |
| 95 | mHandler.removeCallbacks(mScanPackagesRunnable); |
| 96 | |
| 97 | // Stop all providers. |
| 98 | for (int i = mProviderProxies.size() - 1; i >= 0; i--) { |
| 99 | mProviderProxies.get(i).stop(); |
| 100 | } |
| 101 | } |
| 102 | } |
| 103 | |
| 104 | private void scanPackages() { |
| 105 | if (!mRunning) { |
| 106 | return; |
| 107 | } |
| 108 | |
| 109 | if (DEBUG) Log.d(TAG, "scanPackages()"); |
| 110 | // Add providers for all new services. |
| 111 | // Reorder the list so that providers left at the end will be the ones to remove. |
| 112 | int targetIndex = 0; |
| 113 | Intent intent = new Intent(TvRemoteProviderProxy.SERVICE_INTERFACE); |
| 114 | for (ResolveInfo resolveInfo : mPackageManager.queryIntentServicesAsUser( |
| 115 | intent, 0, mUserId)) { |
| 116 | ServiceInfo serviceInfo = resolveInfo.serviceInfo; |
| 117 | if (serviceInfo != null && verifyServiceTrusted(serviceInfo)) { |
| 118 | int sourceIndex = findProvider(serviceInfo.packageName, serviceInfo.name); |
| 119 | if (sourceIndex < 0) { |
| 120 | TvRemoteProviderProxy providerProxy = |
Tom Macieszczak | 34ba4b1 | 2019-09-23 15:24:39 +0200 | [diff] [blame] | 121 | new TvRemoteProviderProxy(mContext, mLock, |
Sujith Ramakrishnan | b5b86c1 | 2016-01-28 16:53:16 -0800 | [diff] [blame] | 122 | new ComponentName(serviceInfo.packageName, serviceInfo.name), |
| 123 | mUserId, serviceInfo.applicationInfo.uid); |
| 124 | providerProxy.start(); |
| 125 | mProviderProxies.add(targetIndex++, providerProxy); |
Sujith Ramakrishnan | b5b86c1 | 2016-01-28 16:53:16 -0800 | [diff] [blame] | 126 | } else if (sourceIndex >= targetIndex) { |
| 127 | TvRemoteProviderProxy provider = mProviderProxies.get(sourceIndex); |
| 128 | provider.start(); // restart the provider if needed |
| 129 | provider.rebindIfDisconnected(); |
| 130 | Collections.swap(mProviderProxies, sourceIndex, targetIndex++); |
| 131 | } |
| 132 | } |
| 133 | } |
| 134 | if (DEBUG) Log.d(TAG, "scanPackages() targetIndex " + targetIndex); |
| 135 | // Remove providers for missing services. |
| 136 | if (targetIndex < mProviderProxies.size()) { |
| 137 | for (int i = mProviderProxies.size() - 1; i >= targetIndex; i--) { |
| 138 | TvRemoteProviderProxy providerProxy = mProviderProxies.get(i); |
Sujith Ramakrishnan | b5b86c1 | 2016-01-28 16:53:16 -0800 | [diff] [blame] | 139 | mProviderProxies.remove(providerProxy); |
| 140 | providerProxy.stop(); |
| 141 | } |
| 142 | } |
| 143 | } |
| 144 | |
Andrei Litvin | b298d4c | 2020-02-27 13:29:20 -0500 | [diff] [blame] | 145 | @VisibleForTesting |
| 146 | boolean verifyServiceTrusted(ServiceInfo serviceInfo) { |
Sujith Ramakrishnan | b5b86c1 | 2016-01-28 16:53:16 -0800 | [diff] [blame] | 147 | if (serviceInfo.permission == null || !serviceInfo.permission.equals( |
| 148 | Manifest.permission.BIND_TV_REMOTE_SERVICE)) { |
| 149 | // If the service does not require this permission then any app could |
| 150 | // potentially bind to it and cause the atv remote provider service to |
| 151 | // misbehave. So we only want to trust providers that require the |
| 152 | // correct permissions. |
| 153 | Slog.w(TAG, "Ignoring atv remote provider service because it did not " |
| 154 | + "require the BIND_TV_REMOTE_SERVICE permission in its manifest: " |
| 155 | + serviceInfo.packageName + "/" + serviceInfo.name); |
| 156 | return false; |
| 157 | } |
| 158 | |
| 159 | // Check if package name is white-listed here. |
| 160 | if (!serviceInfo.packageName.equals(mUnbundledServicePackage)) { |
| 161 | Slog.w(TAG, "Ignoring atv remote provider service because the package has not " |
| 162 | + "been set and/or whitelisted: " |
| 163 | + serviceInfo.packageName + "/" + serviceInfo.name); |
| 164 | return false; |
| 165 | } |
| 166 | |
| 167 | if (!hasNecessaryPermissions(serviceInfo.packageName)) { |
| 168 | // If the service does not have permission to be |
| 169 | // a virtual tv remote controller, do not trust it. |
| 170 | Slog.w(TAG, "Ignoring atv remote provider service because its package does not " |
| 171 | + "have TV_VIRTUAL_REMOTE_CONTROLLER permission: " + serviceInfo.packageName); |
| 172 | return false; |
| 173 | } |
| 174 | |
| 175 | // Looks good. |
| 176 | return true; |
| 177 | } |
| 178 | |
| 179 | // Returns true only if these permissions are present in calling package. |
| 180 | // Manifest.permission.TV_VIRTUAL_REMOTE_CONTROLLER : virtual remote controller on TV |
| 181 | private boolean hasNecessaryPermissions(String packageName) { |
| 182 | if ((mPackageManager.checkPermission(Manifest.permission.TV_VIRTUAL_REMOTE_CONTROLLER, |
| 183 | packageName) == PackageManager.PERMISSION_GRANTED)) { |
| 184 | return true; |
| 185 | } |
| 186 | return false; |
| 187 | } |
| 188 | |
| 189 | private int findProvider(String packageName, String className) { |
| 190 | int count = mProviderProxies.size(); |
| 191 | for (int i = 0; i < count; i++) { |
| 192 | TvRemoteProviderProxy provider = mProviderProxies.get(i); |
| 193 | if (provider.hasComponentName(packageName, className)) { |
| 194 | return i; |
| 195 | } |
| 196 | } |
| 197 | return -1; |
| 198 | } |
| 199 | |
| 200 | private final BroadcastReceiver mScanPackagesReceiver = new BroadcastReceiver() { |
| 201 | @Override |
| 202 | public void onReceive(Context context, Intent intent) { |
| 203 | if (DEBUG) { |
| 204 | Slog.d(TAG, "Received package manager broadcast: " + intent); |
| 205 | } |
| 206 | mHandler.post(mScanPackagesRunnable); |
| 207 | } |
| 208 | }; |
| 209 | |
| 210 | private final Runnable mScanPackagesRunnable = new Runnable() { |
| 211 | @Override |
| 212 | public void run() { |
| 213 | scanPackages(); |
| 214 | } |
| 215 | }; |
Sujith Ramakrishnan | b5b86c1 | 2016-01-28 16:53:16 -0800 | [diff] [blame] | 216 | } |