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 17package com.android.server.webkit; 18 19import android.app.ActivityManager; 20import android.app.AppGlobals; 21import android.content.Context; 22import android.content.pm.ApplicationInfo; 23import android.content.pm.IPackageDeleteObserver; 24import android.content.pm.PackageInfo; 25import android.content.pm.PackageManager; 26import android.content.pm.PackageManager.NameNotFoundException; 27import android.content.pm.UserInfo; 28import android.content.res.XmlResourceParser; 29import android.database.ContentObserver; 30import android.os.Build; 31import android.os.RemoteException; 32import android.os.UserHandle; 33import android.os.UserManager; 34import android.provider.Settings.Global; 35import android.provider.Settings; 36import android.util.AndroidRuntimeException; 37import android.util.Log; 38import android.webkit.UserPackage; 39import android.webkit.WebViewFactory; 40import android.webkit.WebViewProviderInfo; 41import android.webkit.WebViewZygote; 42 43import com.android.internal.util.XmlUtils; 44 45import java.io.IOException; 46import java.util.ArrayList; 47import java.util.List; 48 49import org.xmlpull.v1.XmlPullParserException; 50 51/** 52 * Default implementation for the WebView preparation Utility interface. 53 * @hide 54 */ 55public class SystemImpl implements SystemInterface { 56 private static final String TAG = SystemImpl.class.getSimpleName(); 57 private static final String TAG_START = "webviewproviders"; 58 private static final String TAG_WEBVIEW_PROVIDER = "webviewprovider"; 59 private static final String TAG_PACKAGE_NAME = "packageName"; 60 private static final String TAG_DESCRIPTION = "description"; 61 // Whether or not the provider must be explicitly chosen by the user to be used. 62 private static final String TAG_AVAILABILITY = "availableByDefault"; 63 private static final String TAG_SIGNATURE = "signature"; 64 private static final String TAG_FALLBACK = "isFallback"; 65 private final WebViewProviderInfo[] mWebViewProviderPackages; 66 67 // Initialization-on-demand holder idiom for getting the WebView provider packages once and 68 // for all in a thread-safe manner. 69 private static class LazyHolder { 70 private static final SystemImpl INSTANCE = new SystemImpl(); 71 } 72 73 public static SystemImpl getInstance() { 74 return LazyHolder.INSTANCE; 75 } 76 77 private SystemImpl() { 78 int numFallbackPackages = 0; 79 int numAvailableByDefaultPackages = 0; 80 int numAvByDefaultAndNotFallback = 0; 81 XmlResourceParser parser = null; 82 List<WebViewProviderInfo> webViewProviders = new ArrayList<WebViewProviderInfo>(); 83 try { 84 parser = AppGlobals.getInitialApplication().getResources().getXml( 85 com.android.internal.R.xml.config_webview_packages); 86 XmlUtils.beginDocument(parser, TAG_START); 87 while(true) { 88 XmlUtils.nextElement(parser); 89 String element = parser.getName(); 90 if (element == null) { 91 break; 92 } 93 if (element.equals(TAG_WEBVIEW_PROVIDER)) { 94 String packageName = parser.getAttributeValue(null, TAG_PACKAGE_NAME); 95 if (packageName == null) { 96 throw new AndroidRuntimeException( 97 "WebView provider in framework resources missing package name"); 98 } 99 String description = parser.getAttributeValue(null, TAG_DESCRIPTION); 100 if (description == null) { 101 throw new AndroidRuntimeException( 102 "WebView provider in framework resources missing description"); 103 } 104 boolean availableByDefault = "true".equals( 105 parser.getAttributeValue(null, TAG_AVAILABILITY)); 106 boolean isFallback = "true".equals( 107 parser.getAttributeValue(null, TAG_FALLBACK)); 108 WebViewProviderInfo currentProvider = new WebViewProviderInfo( 109 packageName, description, availableByDefault, isFallback, 110 readSignatures(parser)); 111 if (currentProvider.isFallback) { 112 numFallbackPackages++; 113 if (!currentProvider.availableByDefault) { 114 throw new AndroidRuntimeException( 115 "Each WebView fallback package must be available by default."); 116 } 117 if (numFallbackPackages > 1) { 118 throw new AndroidRuntimeException( 119 "There can be at most one WebView fallback package."); 120 } 121 } 122 if (currentProvider.availableByDefault) { 123 numAvailableByDefaultPackages++; 124 if (!currentProvider.isFallback) { 125 numAvByDefaultAndNotFallback++; 126 } 127 } 128 webViewProviders.add(currentProvider); 129 } 130 else { 131 Log.e(TAG, "Found an element that is not a WebView provider"); 132 } 133 } 134 } catch (XmlPullParserException | IOException e) { 135 throw new AndroidRuntimeException("Error when parsing WebView config " + e); 136 } finally { 137 if (parser != null) parser.close(); 138 } 139 if (numAvailableByDefaultPackages == 0) { 140 throw new AndroidRuntimeException("There must be at least one WebView package " 141 + "that is available by default"); 142 } 143 if (numAvByDefaultAndNotFallback == 0) { 144 throw new AndroidRuntimeException("There must be at least one WebView package " 145 + "that is available by default and not a fallback"); 146 } 147 mWebViewProviderPackages = 148 webViewProviders.toArray(new WebViewProviderInfo[webViewProviders.size()]); 149 } 150 /** 151 * Returns all packages declared in the framework resources as potential WebView providers. 152 * @hide 153 * */ 154 @Override 155 public WebViewProviderInfo[] getWebViewPackages() { 156 return mWebViewProviderPackages; 157 } 158 159 public int getFactoryPackageVersion(String packageName) throws NameNotFoundException { 160 PackageManager pm = AppGlobals.getInitialApplication().getPackageManager(); 161 return pm.getPackageInfo(packageName, PackageManager.MATCH_FACTORY_ONLY).versionCode; 162 } 163 164 /** 165 * Reads all signatures at the current depth (within the current provider) from the XML parser. 166 */ 167 private static String[] readSignatures(XmlResourceParser parser) throws IOException, 168 XmlPullParserException { 169 List<String> signatures = new ArrayList<String>(); 170 int outerDepth = parser.getDepth(); 171 while(XmlUtils.nextElementWithin(parser, outerDepth)) { 172 if (parser.getName().equals(TAG_SIGNATURE)) { 173 // Parse the value within the signature tag 174 String signature = parser.nextText(); 175 signatures.add(signature); 176 } else { 177 Log.e(TAG, "Found an element in a webview provider that is not a signature"); 178 } 179 } 180 return signatures.toArray(new String[signatures.size()]); 181 } 182 183 @Override 184 public int onWebViewProviderChanged(PackageInfo packageInfo) { 185 return WebViewFactory.onWebViewProviderChanged(packageInfo); 186 } 187 188 @Override 189 public String getUserChosenWebViewProvider(Context context) { 190 return Settings.Global.getString(context.getContentResolver(), 191 Settings.Global.WEBVIEW_PROVIDER); 192 } 193 194 @Override 195 public void updateUserSetting(Context context, String newProviderName) { 196 Settings.Global.putString(context.getContentResolver(), 197 Settings.Global.WEBVIEW_PROVIDER, 198 newProviderName == null ? "" : newProviderName); 199 } 200 201 @Override 202 public void killPackageDependents(String packageName) { 203 try { 204 ActivityManager.getService().killPackageDependents(packageName, 205 UserHandle.USER_ALL); 206 } catch (RemoteException e) { 207 } 208 } 209 210 @Override 211 public boolean isFallbackLogicEnabled() { 212 // Note that this is enabled by default (i.e. if the setting hasn't been set). 213 return Settings.Global.getInt(AppGlobals.getInitialApplication().getContentResolver(), 214 Settings.Global.WEBVIEW_FALLBACK_LOGIC_ENABLED, 1) == 1; 215 } 216 217 @Override 218 public void enableFallbackLogic(boolean enable) { 219 Settings.Global.putInt(AppGlobals.getInitialApplication().getContentResolver(), 220 Settings.Global.WEBVIEW_FALLBACK_LOGIC_ENABLED, enable ? 1 : 0); 221 } 222 223 @Override 224 public void uninstallAndDisablePackageForAllUsers(Context context, String packageName) { 225 enablePackageForAllUsers(context, packageName, false); 226 try { 227 PackageManager pm = AppGlobals.getInitialApplication().getPackageManager(); 228 ApplicationInfo applicationInfo = pm.getApplicationInfo(packageName, 0); 229 if (applicationInfo != null && applicationInfo.isUpdatedSystemApp()) { 230 pm.deletePackage(packageName, new IPackageDeleteObserver.Stub() { 231 public void packageDeleted(String packageName, int returnCode) { 232 enablePackageForAllUsers(context, packageName, false); 233 } 234 }, PackageManager.DELETE_SYSTEM_APP | PackageManager.DELETE_ALL_USERS); 235 } 236 } catch (NameNotFoundException e) { 237 } 238 } 239 240 @Override 241 public void enablePackageForAllUsers(Context context, String packageName, boolean enable) { 242 UserManager userManager = (UserManager)context.getSystemService(Context.USER_SERVICE); 243 for(UserInfo userInfo : userManager.getUsers()) { 244 enablePackageForUser(packageName, enable, userInfo.id); 245 } 246 } 247 248 @Override 249 public void enablePackageForUser(String packageName, boolean enable, int userId) { 250 try { 251 AppGlobals.getPackageManager().setApplicationEnabledSetting( 252 packageName, 253 enable ? PackageManager.COMPONENT_ENABLED_STATE_DEFAULT : 254 PackageManager.COMPONENT_ENABLED_STATE_DISABLED_USER, 0, 255 userId, null); 256 } catch (RemoteException | IllegalArgumentException e) { 257 Log.w(TAG, "Tried to " + (enable ? "enable " : "disable ") + packageName 258 + " for user " + userId + ": " + e); 259 } 260 } 261 262 @Override 263 public boolean systemIsDebuggable() { 264 return Build.IS_DEBUGGABLE; 265 } 266 267 @Override 268 public PackageInfo getPackageInfoForProvider(WebViewProviderInfo configInfo) 269 throws NameNotFoundException { 270 PackageManager pm = AppGlobals.getInitialApplication().getPackageManager(); 271 return pm.getPackageInfo(configInfo.packageName, PACKAGE_FLAGS); 272 } 273 274 @Override 275 public List<UserPackage> getPackageInfoForProviderAllUsers(Context context, 276 WebViewProviderInfo configInfo) { 277 return UserPackage.getPackageInfosAllUsers(context, configInfo.packageName, PACKAGE_FLAGS); 278 } 279 280 @Override 281 public int getMultiProcessSetting(Context context) { 282 return Settings.Global.getInt(context.getContentResolver(), 283 Settings.Global.WEBVIEW_MULTIPROCESS, 0); 284 } 285 286 @Override 287 public void setMultiProcessSetting(Context context, int value) { 288 Settings.Global.putInt(context.getContentResolver(), 289 Settings.Global.WEBVIEW_MULTIPROCESS, value); 290 } 291 292 @Override 293 public void notifyZygote(boolean enableMultiProcess) { 294 WebViewZygote.setMultiprocessEnabled(enableMultiProcess); 295 } 296 297 @Override 298 public boolean isMultiProcessDefaultEnabled() { 299 return true; 300 } 301 302 // flags declaring we want extra info from the package manager for webview providers 303 private final static int PACKAGE_FLAGS = PackageManager.GET_META_DATA 304 | PackageManager.GET_SIGNATURES | PackageManager.MATCH_DEBUG_TRIAGED_MISSING 305 | PackageManager.MATCH_ANY_USER; 306} 307