Use the WebView's loader library to load the real library. (08cfaf67) · Commits · e / os / android_frameworks_base

Android.mk

+1 −0

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		@@ -241,6 +241,7 @@ LOCAL_SRC_FILES += \
		core/java/android/view/IWindowManager.aidl \
		core/java/android/view/IWindowSession.aidl \
		core/java/android/view/IWindowSessionCallback.aidl \
		core/java/android/webkit/IWebViewUpdateService.aidl \
		core/java/android/speech/IRecognitionListener.aidl \
		core/java/android/speech/IRecognitionService.aidl \
		core/java/android/speech/tts/ITextToSpeechCallback.aidl \

core/java/android/os/Process.java

+6 −0

Original line number	Diff line number	Diff line
		@@ -130,6 +130,12 @@ public class Process {
		*/
		public static final int PACKAGE_INFO_GID = 1032;

		/**
		* Defines the UID/GID for the shared RELRO file updater process.
		* @hide
		*/
		public static final int SHARED_RELRO_UID = 1037;

		/**
		* Defines the start of a range of UIDs (and GIDs), going from this
		* number to {@link #LAST_APPLICATION_UID} that are reserved for assigning

core/java/android/webkit/IWebViewUpdateService.aidl

0 → 100644

+36 −0

Original line number	Diff line number	Diff line
		/*
		* Copyright (C) 2014 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;

		/**
		* Private service to wait for the updatable WebView to be ready for use.
		* @hide
		*/
		interface IWebViewUpdateService {

		/**
		* Used by the relro file creator to notify the service that it's done.
		*/
		void notifyRelroCreationCompleted(boolean is64Bit, boolean success);

		/**
		* Used by WebViewFactory to block loading of WebView code until
		* preparations are complete.
		*/
		void waitForRelroCreationCompleted(boolean is64Bit);

		}

core/java/android/webkit/WebViewFactory.java

+140 −0

Original line number	Diff line number	Diff line
		@@ -16,9 +16,18 @@

		package android.webkit;

		import android.os.Build;
		import android.os.Process;
		import android.os.RemoteException;
		import android.os.ServiceManager;
		import android.os.StrictMode;
		import android.util.AndroidRuntimeException;
		import android.util.Log;
		import dalvik.system.VMRuntime;

		import java.io.File;

		import com.android.internal.os.Zygote;

		/**
		* Top level factory, used creating all the main WebView implementation classes.
		@@ -33,6 +42,17 @@ public final class WebViewFactory {
		private static final String NULL_WEBVIEW_FACTORY =
		"com.android.webview.nullwebview.NullWebViewFactoryProvider";

		// TODO(torne): we need to use a system property instead of hardcoding the library paths to
		// enable it to be changed when a webview update apk is installed.
		private static final String CHROMIUM_WEBVIEW_NATIVE_LIB_32 =
		"/system/lib/libwebviewchromium.so";
		private static final String CHROMIUM_WEBVIEW_NATIVE_LIB_64 =
		"/system/lib64/libwebviewchromium.so";
		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";

		private static final String LOGTAG = "WebViewFactory";

		private static final boolean DEBUG = false;
		@@ -41,6 +61,7 @@ public final class WebViewFactory {
		// same provider.
		private static WebViewFactoryProvider sProviderInstance;
		private static final Object sProviderLock = new Object();
		private static boolean sAddressSpaceReserved = false;

		static WebViewFactoryProvider getProvider() {
		synchronized (sProviderLock) {
		@@ -48,6 +69,8 @@ public final class WebViewFactory {
		// us honest and minimize usage of WebView internals when binding the proxy.
		if (sProviderInstance != null) return sProviderInstance;

		loadNativeLibrary();

		Class<WebViewFactoryProvider> providerClass;
		try {
		providerClass = getFactoryClass();
		@@ -78,4 +101,121 @@ public final class WebViewFactory {
		return (Class<WebViewFactoryProvider>) Class.forName(NULL_WEBVIEW_FACTORY);
		}
		}

		/**
		* 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");
		sAddressSpaceReserved = nativeReserveAddressSpace(CHROMIUM_WEBVIEW_NATIVE_LIB_32,
		CHROMIUM_WEBVIEW_NATIVE_LIB_64);
		if (sAddressSpaceReserved) {
		if (DEBUG) Log.v(LOGTAG, "address space reserved");
		} else {
		Log.e(LOGTAG, "reserving address space failed");
		}
		} catch (Throwable e) {
		// Log and discard errors at this stage as we must not crash the zygote.
		Log.e(LOGTAG, "error preparing native loader", e);
		}
		}

		/**
		* Perform any WebView loading preparations that must happen at boot from the system server,
		* after the package manager has started.
		* 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() {
		if (DEBUG) Log.v(LOGTAG, "creating relro files");
		if (new File(CHROMIUM_WEBVIEW_NATIVE_LIB_64).exists()) {
		createRelroFile(Build.SUPPORTED_64_BIT_ABIS[0]);
		}
		if (new File(CHROMIUM_WEBVIEW_NATIVE_LIB_32).exists()) {
		createRelroFile(Build.SUPPORTED_32_BIT_ABIS[0]);
		}
		}

		private static void createRelroFile(String abi) {
		try {
		Process.start("android.webkit.WebViewFactory$RelroFileCreator",
		"WebViewLoader-" + abi,
		Process.SHARED_RELRO_UID,
		Process.SHARED_RELRO_UID,
		null,
		0, // TODO(torne): do we need to set debug flags?
		Zygote.MOUNT_EXTERNAL_NONE,
		Build.VERSION.SDK_INT,
		null,
		abi,
		null);
		} catch (Throwable e) {
		// Log and discard errors as we must not crash the system server.
		Log.e(LOGTAG, "error starting relro file creator for abi " + abi, e);
		}
		}

		private static class RelroFileCreator {
		// Called in an unprivileged child process to create the relro file.
		public static void main(String[] args) {
		if (!sAddressSpaceReserved) {
		Log.e(LOGTAG, "can't create relro file; address space not reserved");
		return;
		}
		boolean result = nativeCreateRelroFile(CHROMIUM_WEBVIEW_NATIVE_LIB_32,
		CHROMIUM_WEBVIEW_NATIVE_LIB_64,
		CHROMIUM_WEBVIEW_NATIVE_RELRO_32,
		CHROMIUM_WEBVIEW_NATIVE_RELRO_64);
		if (!result) {
		Log.e(LOGTAG, "failed to create relro file");
		} else if (DEBUG) {
		Log.v(LOGTAG, "created relro file");
		}
		try {
		getUpdateService().notifyRelroCreationCompleted(VMRuntime.getRuntime().is64Bit(),
		result);
		} catch (RemoteException e) {
		Log.e(LOGTAG, "error notifying update service", e);
		}

		// Must explicitly exit or else this process will just sit around after we return.
		System.exit(0);
		}
		}

		private static void loadNativeLibrary() {
		if (!sAddressSpaceReserved) {
		Log.e(LOGTAG, "can't load with relro file; address space not reserved");
		return;
		}

		try {
		getUpdateService().waitForRelroCreationCompleted(VMRuntime.getRuntime().is64Bit());
		} catch (RemoteException e) {
		Log.e(LOGTAG, "error waiting for relro creation, proceeding without", e);
		return;
		}

		boolean result = nativeLoadWithRelroFile(CHROMIUM_WEBVIEW_NATIVE_LIB_32,
		CHROMIUM_WEBVIEW_NATIVE_LIB_64,
		CHROMIUM_WEBVIEW_NATIVE_RELRO_32,
		CHROMIUM_WEBVIEW_NATIVE_RELRO_64);
		if (!result) {
		Log.w(LOGTAG, "failed to load with relro file, proceeding without");
		} else if (DEBUG) {
		Log.v(LOGTAG, "loaded with relro file");
		}
		}

		private static IWebViewUpdateService getUpdateService() {
		return IWebViewUpdateService.Stub.asInterface(ServiceManager.getService("webviewupdate"));
		}

		private static native boolean nativeReserveAddressSpace(String lib32, String lib64);
		private static native boolean nativeCreateRelroFile(String lib32, String lib64,
		String relro32, String relro64);
		private static native boolean nativeLoadWithRelroFile(String lib32, String lib64,
		String relro32, String relro64);
		}

core/java/com/android/internal/os/ZygoteInit.java

+4 −0

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		@@ -34,6 +34,7 @@ import android.system.Os;
		import android.system.OsConstants;
		import android.util.EventLog;
		import android.util.Log;
		import android.webkit.WebViewFactory;

		import dalvik.system.VMRuntime;

		@@ -250,6 +251,9 @@ public class ZygoteInit {
		preloadClasses();
		preloadResources();
		preloadOpenGL();
		// Ask the WebViewFactory to do any initialization that must run in the zygote process,
		// for memory sharing purposes.
		WebViewFactory.prepareWebViewInZygote();
		Log.d(TAG, "end preload");
		}