/* * 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 android.webkit; import android.annotation.SystemApi; import android.app.ActivityManagerInternal; import android.app.AppGlobals; import android.app.Application; import android.content.Context; import android.content.pm.ApplicationInfo; import android.content.pm.PackageInfo; import android.content.pm.PackageManager; import android.os.Build; import android.os.Process; import android.os.RemoteException; import android.os.ServiceManager; import android.os.StrictMode; import android.os.SystemProperties; import android.os.Trace; import android.text.TextUtils; import android.util.AndroidRuntimeException; import android.util.Log; import com.android.server.LocalServices; import dalvik.system.VMRuntime; import java.io.File; import java.io.IOException; import java.util.Arrays; import java.util.zip.ZipEntry; import java.util.zip.ZipFile; /** * Top level factory, used creating all the main WebView implementation classes. * * @hide */ @SystemApi public final class WebViewFactory { private static final String CHROMIUM_WEBVIEW_FACTORY = "com.android.webview.chromium.WebViewChromiumFactoryProvider"; private static final String NULL_WEBVIEW_FACTORY = "com.android.webview.nullwebview.NullWebViewFactoryProvider"; private static final String CHROMIUM_WEBVIEW_NATIVE_RELRO_32 = "/data/misc/shared_relro/libwebviewchromium32.relro"; private static final String CHROMIUM_WEBVIEW_NATIVE_RELRO_64 = "/data/misc/shared_relro/libwebviewchromium64.relro"; public static final String CHROMIUM_WEBVIEW_VMSIZE_SIZE_PROPERTY = "persist.sys.webview.vmsize"; private static final long CHROMIUM_WEBVIEW_DEFAULT_VMSIZE_BYTES = 100 * 1024 * 1024; private static final String LOGTAG = "WebViewFactory"; private static final boolean DEBUG = false; // Cache the factory both for efficiency, and ensure any one process gets all webviews from the // same provider. private static WebViewFactoryProvider sProviderInstance; private static final Object sProviderLock = new Object(); private static boolean sAddressSpaceReserved = false; private static PackageInfo sPackageInfo; // Error codes for loadWebViewNativeLibraryFromPackage public static final int LIBLOAD_SUCCESS = 0; public static final int LIBLOAD_WRONG_PACKAGE_NAME = 1; public static final int LIBLOAD_ADDRESS_SPACE_NOT_RESERVED = 2; public static final int LIBLOAD_FAILED_WAITING_FOR_RELRO = 3; public static final int LIBLOAD_FAILED_LISTING_WEBVIEW_PACKAGES = 4; // native relro loading error codes public static final int LIBLOAD_FAILED_TO_OPEN_RELRO_FILE = 5; public static final int LIBLOAD_FAILED_TO_LOAD_LIBRARY = 6; public static final int LIBLOAD_FAILED_JNI_CALL = 7; private static class MissingWebViewPackageException extends AndroidRuntimeException { public MissingWebViewPackageException(String message) { super(message); } public MissingWebViewPackageException(Exception e) { super(e); } } public static String getWebViewPackageName() { return AppGlobals.getInitialApplication().getString( com.android.internal.R.string.config_webViewPackageName); } private static PackageInfo fetchPackageInfo() { PackageManager pm = AppGlobals.getInitialApplication().getPackageManager(); try { return pm.getPackageInfo(getWebViewPackageName(), PackageManager.GET_META_DATA); } catch (PackageManager.NameNotFoundException e) { throw new MissingWebViewPackageException(e); } } // throws MissingWebViewPackageException private static ApplicationInfo getWebViewApplicationInfo() { if (sPackageInfo == null) { return fetchPackageInfo().applicationInfo; } else { return sPackageInfo.applicationInfo; } } private static String getWebViewLibrary(ApplicationInfo ai) { if (ai.metaData != null) return ai.metaData.getString("com.android.webview.WebViewLibrary"); return null; } public static PackageInfo getLoadedPackageInfo() { return sPackageInfo; } /** * Load the native library for the given package name iff that package * name is the same as the one providing the webview. */ public static int loadWebViewNativeLibraryFromPackage(String packageName) { sPackageInfo = fetchPackageInfo(); if (packageName != null && packageName.equals(sPackageInfo.packageName)) { return loadNativeLibrary(); } return LIBLOAD_WRONG_PACKAGE_NAME; } static WebViewFactoryProvider getProvider() { synchronized (sProviderLock) { // For now the main purpose of this function (and the factory abstraction) is to keep // us honest and minimize usage of WebView internals when binding the proxy. if (sProviderInstance != null) return sProviderInstance; final int uid = android.os.Process.myUid(); if (uid == android.os.Process.ROOT_UID || uid == android.os.Process.SYSTEM_UID) { throw new UnsupportedOperationException( "For security reasons, WebView is not allowed in privileged processes"); } Trace.traceBegin(Trace.TRACE_TAG_WEBVIEW, "WebViewFactory.getProvider()"); try { Class providerClass = getProviderClass(); StrictMode.ThreadPolicy oldPolicy = StrictMode.allowThreadDiskReads(); Trace.traceBegin(Trace.TRACE_TAG_WEBVIEW, "providerClass.newInstance()"); try { sProviderInstance = providerClass.getConstructor(WebViewDelegate.class) .newInstance(new WebViewDelegate()); if (DEBUG) Log.v(LOGTAG, "Loaded provider: " + sProviderInstance); return sProviderInstance; } catch (Exception e) { Log.e(LOGTAG, "error instantiating provider", e); throw new AndroidRuntimeException(e); } finally { Trace.traceEnd(Trace.TRACE_TAG_WEBVIEW); StrictMode.setThreadPolicy(oldPolicy); } } finally { Trace.traceEnd(Trace.TRACE_TAG_WEBVIEW); } } } private static Class getProviderClass() { try { // First fetch the package info so we can log the webview package version. sPackageInfo = fetchPackageInfo(); Log.i(LOGTAG, "Loading " + sPackageInfo.packageName + " version " + sPackageInfo.versionName + " (code " + sPackageInfo.versionCode + ")"); Trace.traceBegin(Trace.TRACE_TAG_WEBVIEW, "WebViewFactory.loadNativeLibrary()"); loadNativeLibrary(); Trace.traceEnd(Trace.TRACE_TAG_WEBVIEW); Trace.traceBegin(Trace.TRACE_TAG_WEBVIEW, "WebViewFactory.getChromiumProviderClass()"); try { return getChromiumProviderClass(); } catch (ClassNotFoundException e) { Log.e(LOGTAG, "error loading provider", e); throw new AndroidRuntimeException(e); } finally { Trace.traceEnd(Trace.TRACE_TAG_WEBVIEW); } } catch (MissingWebViewPackageException e) { // If the package doesn't exist, then try loading the null WebView instead. // If that succeeds, then this is a device without WebView support; if it fails then // swallow the failure, complain that the real WebView is missing and rethrow the // original exception. try { return (Class) Class.forName(NULL_WEBVIEW_FACTORY); } catch (ClassNotFoundException e2) { // Ignore. } Log.e(LOGTAG, "Chromium WebView package does not exist", e); throw new AndroidRuntimeException(e); } } // throws MissingWebViewPackageException private static Class getChromiumProviderClass() throws ClassNotFoundException { Application initialApplication = AppGlobals.getInitialApplication(); try { // Construct a package context to load the Java code into the current app. Context webViewContext = initialApplication.createPackageContext( sPackageInfo.packageName, Context.CONTEXT_INCLUDE_CODE | Context.CONTEXT_IGNORE_SECURITY); initialApplication.getAssets().addAssetPath( webViewContext.getApplicationInfo().sourceDir); ClassLoader clazzLoader = webViewContext.getClassLoader(); Trace.traceBegin(Trace.TRACE_TAG_WEBVIEW, "Class.forName()"); try { return (Class) Class.forName(CHROMIUM_WEBVIEW_FACTORY, true, clazzLoader); } finally { Trace.traceEnd(Trace.TRACE_TAG_WEBVIEW); } } catch (PackageManager.NameNotFoundException e) { throw new MissingWebViewPackageException(e); } } /** * Perform any WebView loading preparations that must happen in the zygote. * Currently, this means allocating address space to load the real JNI library later. */ public static void prepareWebViewInZygote() { try { System.loadLibrary("webviewchromium_loader"); long addressSpaceToReserve = SystemProperties.getLong(CHROMIUM_WEBVIEW_VMSIZE_SIZE_PROPERTY, CHROMIUM_WEBVIEW_DEFAULT_VMSIZE_BYTES); sAddressSpaceReserved = nativeReserveAddressSpace(addressSpaceToReserve); if (sAddressSpaceReserved) { if (DEBUG) { Log.v(LOGTAG, "address space reserved: " + addressSpaceToReserve + " bytes"); } } else { Log.e(LOGTAG, "reserving " + addressSpaceToReserve + " bytes of address space failed"); } } catch (Throwable t) { // Log and discard errors at this stage as we must not crash the zygote. Log.e(LOGTAG, "error preparing native loader", t); } } /** * Perform any WebView loading preparations that must happen at boot from the system server, * after the package manager has started or after an update to the webview is installed. * This must be called in the system server. * Currently, this means spawning the child processes which will create the relro files. */ public static void prepareWebViewInSystemServer() { String[] nativePaths = null; try { nativePaths = getWebViewNativeLibraryPaths(); } catch (Throwable t) { // Log and discard errors at this stage as we must not crash the system server. Log.e(LOGTAG, "error preparing webview native library", t); } prepareWebViewInSystemServer(nativePaths); } private static void prepareWebViewInSystemServer(String[] nativeLibraryPaths) { if (DEBUG) Log.v(LOGTAG, "creating relro files"); // We must always trigger createRelRo regardless of the value of nativeLibraryPaths. Any // unexpected values will be handled there to ensure that we trigger notifying any process // waiting on relreo creation. if (Build.SUPPORTED_32_BIT_ABIS.length > 0) { if (DEBUG) Log.v(LOGTAG, "Create 32 bit relro"); createRelroFile(false /* is64Bit */, nativeLibraryPaths); } if (Build.SUPPORTED_64_BIT_ABIS.length > 0) { if (DEBUG) Log.v(LOGTAG, "Create 64 bit relro"); createRelroFile(true /* is64Bit */, nativeLibraryPaths); } } public static void onWebViewUpdateInstalled() { String[] nativeLibs = null; try { nativeLibs = WebViewFactory.getWebViewNativeLibraryPaths(); if (nativeLibs != null) { long newVmSize = 0L; for (String path : nativeLibs) { if (path == null || TextUtils.isEmpty(path)) continue; if (DEBUG) Log.d(LOGTAG, "Checking file size of " + path); File f = new File(path); if (f.exists()) { newVmSize = Math.max(newVmSize, f.length()); continue; } if (path.contains("!/")) { String[] split = TextUtils.split(path, "!/"); if (split.length == 2) { try (ZipFile z = new ZipFile(split[0])) { ZipEntry e = z.getEntry(split[1]); if (e != null && e.getMethod() == ZipEntry.STORED) { newVmSize = Math.max(newVmSize, e.getSize()); continue; } } catch (IOException e) { Log.e(LOGTAG, "error reading APK file " + split[0] + ", ", e); } } } Log.e(LOGTAG, "error sizing load for " + path); } if (DEBUG) { Log.v(LOGTAG, "Based on library size, need " + newVmSize + " bytes of address space."); } // The required memory can be larger than the file on disk (due to .bss), and an // upgraded version of the library will likely be larger, so always attempt to // reserve twice as much as we think to allow for the library to grow during this // boot cycle. newVmSize = Math.max(2 * newVmSize, CHROMIUM_WEBVIEW_DEFAULT_VMSIZE_BYTES); Log.d(LOGTAG, "Setting new address space to " + newVmSize); SystemProperties.set(CHROMIUM_WEBVIEW_VMSIZE_SIZE_PROPERTY, Long.toString(newVmSize)); } } catch (Throwable t) { // Log and discard errors at this stage as we must not crash the system server. Log.e(LOGTAG, "error preparing webview native library", t); } prepareWebViewInSystemServer(nativeLibs); } // throws MissingWebViewPackageException private static String getLoadFromApkPath(String apkPath, String[] abiList, String nativeLibFileName) { // Search the APK for a native library conforming to a listed ABI. try (ZipFile z = new ZipFile(apkPath)) { for (String abi : abiList) { final String entry = "lib/" + abi + "/" + nativeLibFileName; ZipEntry e = z.getEntry(entry); if (e != null && e.getMethod() == ZipEntry.STORED) { // Return a path formatted for dlopen() load from APK. return apkPath + "!/" + entry; } } } catch (IOException e) { throw new MissingWebViewPackageException(e); } return ""; } // throws MissingWebViewPackageException private static String[] getWebViewNativeLibraryPaths() { ApplicationInfo ai = getWebViewApplicationInfo(); final String NATIVE_LIB_FILE_NAME = getWebViewLibrary(ai); String path32; String path64; boolean primaryArchIs64bit = VMRuntime.is64BitAbi(ai.primaryCpuAbi); if (!TextUtils.isEmpty(ai.secondaryCpuAbi)) { // Multi-arch case. if (primaryArchIs64bit) { // Primary arch: 64-bit, secondary: 32-bit. path64 = ai.nativeLibraryDir; path32 = ai.secondaryNativeLibraryDir; } else { // Primary arch: 32-bit, secondary: 64-bit. path64 = ai.secondaryNativeLibraryDir; path32 = ai.nativeLibraryDir; } } else if (primaryArchIs64bit) { // Single-arch 64-bit. path64 = ai.nativeLibraryDir; path32 = ""; } else { // Single-arch 32-bit. path32 = ai.nativeLibraryDir; path64 = ""; } // Form the full paths to the extracted native libraries. // If libraries were not extracted, try load from APK paths instead. if (!TextUtils.isEmpty(path32)) { path32 += "/" + NATIVE_LIB_FILE_NAME; File f = new File(path32); if (!f.exists()) { path32 = getLoadFromApkPath(ai.sourceDir, Build.SUPPORTED_32_BIT_ABIS, NATIVE_LIB_FILE_NAME); } } if (!TextUtils.isEmpty(path64)) { path64 += "/" + NATIVE_LIB_FILE_NAME; File f = new File(path64); if (!f.exists()) { path64 = getLoadFromApkPath(ai.sourceDir, Build.SUPPORTED_64_BIT_ABIS, NATIVE_LIB_FILE_NAME); } } if (DEBUG) Log.v(LOGTAG, "Native 32-bit lib: " + path32 + ", 64-bit lib: " + path64); return new String[] { path32, path64 }; } private static void createRelroFile(final boolean is64Bit, String[] nativeLibraryPaths) { final String abi = is64Bit ? Build.SUPPORTED_64_BIT_ABIS[0] : Build.SUPPORTED_32_BIT_ABIS[0]; // crashHandler is invoked by the ActivityManagerService when the isolated process crashes. Runnable crashHandler = new Runnable() { @Override public void run() { try { Log.e(LOGTAG, "relro file creator for " + abi + " crashed. Proceeding without"); getUpdateService().notifyRelroCreationCompleted(is64Bit, false); } catch (RemoteException e) { Log.e(LOGTAG, "Cannot reach WebViewUpdateService. " + e.getMessage()); } } }; try { if (nativeLibraryPaths == null || nativeLibraryPaths[0] == null || nativeLibraryPaths[1] == null) { throw new IllegalArgumentException( "Native library paths to the WebView RelRo process must not be null!"); } int pid = LocalServices.getService(ActivityManagerInternal.class).startIsolatedProcess( RelroFileCreator.class.getName(), nativeLibraryPaths, "WebViewLoader-" + abi, abi, Process.SHARED_RELRO_UID, crashHandler); if (pid <= 0) throw new Exception("Failed to start the relro file creator process"); } catch (Throwable t) { // Log and discard errors as we must not crash the system server. Log.e(LOGTAG, "error starting relro file creator for abi " + abi, t); crashHandler.run(); } } private static class RelroFileCreator { // Called in an unprivileged child process to create the relro file. public static void main(String[] args) { boolean result = false; boolean is64Bit = VMRuntime.getRuntime().is64Bit(); try{ if (args.length != 2 || args[0] == null || args[1] == null) { Log.e(LOGTAG, "Invalid RelroFileCreator args: " + Arrays.toString(args)); return; } Log.v(LOGTAG, "RelroFileCreator (64bit = " + is64Bit + "), " + " 32-bit lib: " + args[0] + ", 64-bit lib: " + args[1]); if (!sAddressSpaceReserved) { Log.e(LOGTAG, "can't create relro file; address space not reserved"); return; } result = nativeCreateRelroFile(args[0] /* path32 */, args[1] /* path64 */, CHROMIUM_WEBVIEW_NATIVE_RELRO_32, CHROMIUM_WEBVIEW_NATIVE_RELRO_64); if (result && DEBUG) Log.v(LOGTAG, "created relro file"); } finally { // We must do our best to always notify the update service, even if something fails. try { getUpdateService().notifyRelroCreationCompleted(is64Bit, result); } catch (RemoteException e) { Log.e(LOGTAG, "error notifying update service", e); } if (!result) Log.e(LOGTAG, "failed to create relro file"); // Must explicitly exit or else this process will just sit around after we return. System.exit(0); } } } private static int loadNativeLibrary() { if (!sAddressSpaceReserved) { Log.e(LOGTAG, "can't load with relro file; address space not reserved"); return LIBLOAD_ADDRESS_SPACE_NOT_RESERVED; } try { getUpdateService().waitForRelroCreationCompleted(VMRuntime.getRuntime().is64Bit()); } catch (RemoteException e) { Log.e(LOGTAG, "error waiting for relro creation, proceeding without", e); return LIBLOAD_FAILED_WAITING_FOR_RELRO; } try { String[] args = getWebViewNativeLibraryPaths(); int result = nativeLoadWithRelroFile(args[0] /* path32 */, args[1] /* path64 */, CHROMIUM_WEBVIEW_NATIVE_RELRO_32, CHROMIUM_WEBVIEW_NATIVE_RELRO_64); if (result != LIBLOAD_SUCCESS) { Log.w(LOGTAG, "failed to load with relro file, proceeding without"); } else if (DEBUG) { Log.v(LOGTAG, "loaded with relro file"); } return result; } catch (MissingWebViewPackageException e) { Log.e(LOGTAG, "Failed to list WebView package libraries for loadNativeLibrary", e); return LIBLOAD_FAILED_LISTING_WEBVIEW_PACKAGES; } } private static IWebViewUpdateService getUpdateService() { return IWebViewUpdateService.Stub.asInterface(ServiceManager.getService("webviewupdate")); } private static native boolean nativeReserveAddressSpace(long addressSpaceToReserve); private static native boolean nativeCreateRelroFile(String lib32, String lib64, String relro32, String relro64); private static native int nativeLoadWithRelroFile(String lib32, String lib64, String relro32, String relro64); }