core/java/android/webkit/WebViewLibraryLoader.java - platform/frameworks/base - Git at Google

 /*
  * 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 android.webkit;

 import android.app.ActivityManagerInternal;
 import android.content.pm.ApplicationInfo;
 import android.content.pm.PackageInfo;
 import android.os.Build;
 import android.os.Process;
 import android.os.RemoteException;
 import android.os.SystemProperties;
 import android.text.TextUtils;
 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;

 class WebViewLibraryLoader {
     private static final String LOGTAG = WebViewLibraryLoader.class.getSimpleName();

     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 long CHROMIUM_WEBVIEW_DEFAULT_VMSIZE_BYTES = 100 * 1024 * 1024;

     private static final boolean DEBUG = false;

     private static boolean sAddressSpaceReserved = false;

     /**
      * Private class for running the actual relro creation in an unprivileged child process.
      * RelroFileCreator is a static class (without access to the outer class) to avoid accidentally
      * using any static members from the outer class. Those members will in reality differ between
      * the child process in which RelroFileCreator operates, and the app process in which the static
      * members of this class are used.
      */
     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 {
                     WebViewFactory.getUpdateService().notifyRelroCreationCompleted();
                 } 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);
             }
         }
     }

     /**
      * Create a single relro file by invoking an isolated process that to do the actual work.
      */
     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");
                     WebViewFactory.getUpdateService().notifyRelroCreationCompleted();
                 } 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();
         }
     }

     /**
      *
      * @return the native WebView libraries in the new WebView APK.
      */
     static String[] updateWebViewZygoteVmSize(PackageInfo packageInfo)
             throws WebViewFactory.MissingWebViewPackageException {
         // Find the native libraries of the new WebView package, to change the size of the
         // memory region in the Zygote reserved for the library.
         String[] nativeLibs = getWebViewNativeLibraryPaths(packageInfo);
         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);
             setWebViewZygoteVmSize(newVmSize);
         }
         return nativeLibs;
     }

     /**
      * Reserve space for the native library to be loaded into.
      */
     static void reserveAddressSpaceInZygote() {
         System.loadLibrary("webviewchromium_loader");
         long addressSpaceToReserve =
                 SystemProperties.getLong(WebViewFactory.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");
         }
     }

     /**
      * Load WebView's native library into the current process.
      * Note: assumes that we have waited for relro creation.
      * @param clazzLoader class loader used to find the linker namespace to load the library into.
      * @param packageInfo the package from which WebView is loaded.
      */
     static int loadNativeLibrary(ClassLoader clazzLoader, PackageInfo packageInfo)
             throws WebViewFactory.MissingWebViewPackageException {
         if (!sAddressSpaceReserved) {
             Log.e(LOGTAG, "can't load with relro file; address space not reserved");
             return WebViewFactory.LIBLOAD_ADDRESS_SPACE_NOT_RESERVED;
         }

         final String libraryFileName =
                 WebViewFactory.getWebViewLibrary(packageInfo.applicationInfo);
         int result = nativeLoadWithRelroFile(libraryFileName, CHROMIUM_WEBVIEW_NATIVE_RELRO_32,
                                              CHROMIUM_WEBVIEW_NATIVE_RELRO_64, clazzLoader);
         if (result != WebViewFactory.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;
     }

     /**
      * Fetch WebView's native library paths from {@param packageInfo}.
      */
     static String[] getWebViewNativeLibraryPaths(PackageInfo packageInfo)
             throws WebViewFactory.MissingWebViewPackageException {
         ApplicationInfo ai = packageInfo.applicationInfo;
         final String nativeLibFileName = WebViewFactory.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 += "/" + nativeLibFileName;
             File f = new File(path32);
             if (!f.exists()) {
                 path32 = getLoadFromApkPath(ai.sourceDir,
                                             Build.SUPPORTED_32_BIT_ABIS,
                                             nativeLibFileName);
             }
         }
         if (!TextUtils.isEmpty(path64)) {
             path64 += "/" + nativeLibFileName;
             File f = new File(path64);
             if (!f.exists()) {
                 path64 = getLoadFromApkPath(ai.sourceDir,
                                             Build.SUPPORTED_64_BIT_ABIS,
                                             nativeLibFileName);
             }
         }

         if (DEBUG) Log.v(LOGTAG, "Native 32-bit lib: " + path32 + ", 64-bit lib: " + path64);
         return new String[] { path32, path64 };
     }

     private static String getLoadFromApkPath(String apkPath,
                                              String[] abiList,
                                              String nativeLibFileName)
             throws WebViewFactory.MissingWebViewPackageException {
         // 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 WebViewFactory.MissingWebViewPackageException(e);
         }
         return "";
     }

     /**
      * Sets the size of the memory area in which to store the relro section.
      */
     private static void setWebViewZygoteVmSize(long vmSize) {
         SystemProperties.set(WebViewFactory.CHROMIUM_WEBVIEW_VMSIZE_SIZE_PROPERTY,
                 Long.toString(vmSize));
     }

     static native boolean nativeReserveAddressSpace(long addressSpaceToReserve);
     static native boolean nativeCreateRelroFile(String lib32, String lib64,
                                                         String relro32, String relro64);
     static native int nativeLoadWithRelroFile(String lib, String relro32, String relro64,
                                                       ClassLoader clazzLoader);
 }
	/*
	* 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 android.webkit;

	import android.app.ActivityManagerInternal;
	import android.content.pm.ApplicationInfo;
	import android.content.pm.PackageInfo;
	import android.os.Build;
	import android.os.Process;
	import android.os.RemoteException;
	import android.os.SystemProperties;
	import android.text.TextUtils;
	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;

	class WebViewLibraryLoader {
	private static final String LOGTAG = WebViewLibraryLoader.class.getSimpleName();

	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 long CHROMIUM_WEBVIEW_DEFAULT_VMSIZE_BYTES = 100 * 1024 * 1024;

	private static final boolean DEBUG = false;

	private static boolean sAddressSpaceReserved = false;

	/**
	* Private class for running the actual relro creation in an unprivileged child process.
	* RelroFileCreator is a static class (without access to the outer class) to avoid accidentally
	* using any static members from the outer class. Those members will in reality differ between
	* the child process in which RelroFileCreator operates, and the app process in which the static
	* members of this class are used.
	*/
	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 {
	WebViewFactory.getUpdateService().notifyRelroCreationCompleted();
	} 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);
	}
	}
	}

	/**
	* Create a single relro file by invoking an isolated process that to do the actual work.
	*/
	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");
	WebViewFactory.getUpdateService().notifyRelroCreationCompleted();
	} 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();
	}
	}

	/**
	*
	* @return the native WebView libraries in the new WebView APK.
	*/
	static String[] updateWebViewZygoteVmSize(PackageInfo packageInfo)
	throws WebViewFactory.MissingWebViewPackageException {
	// Find the native libraries of the new WebView package, to change the size of the
	// memory region in the Zygote reserved for the library.
	String[] nativeLibs = getWebViewNativeLibraryPaths(packageInfo);
	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);
	setWebViewZygoteVmSize(newVmSize);
	}
	return nativeLibs;
	}

	/**
	* Reserve space for the native library to be loaded into.
	*/
	static void reserveAddressSpaceInZygote() {
	System.loadLibrary("webviewchromium_loader");
	long addressSpaceToReserve =
	SystemProperties.getLong(WebViewFactory.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");
	}
	}

	/**
	* Load WebView's native library into the current process.
	* Note: assumes that we have waited for relro creation.
	* @param clazzLoader class loader used to find the linker namespace to load the library into.
	* @param packageInfo the package from which WebView is loaded.
	*/
	static int loadNativeLibrary(ClassLoader clazzLoader, PackageInfo packageInfo)
	throws WebViewFactory.MissingWebViewPackageException {
	if (!sAddressSpaceReserved) {
	Log.e(LOGTAG, "can't load with relro file; address space not reserved");
	return WebViewFactory.LIBLOAD_ADDRESS_SPACE_NOT_RESERVED;
	}

	final String libraryFileName =
	WebViewFactory.getWebViewLibrary(packageInfo.applicationInfo);
	int result = nativeLoadWithRelroFile(libraryFileName, CHROMIUM_WEBVIEW_NATIVE_RELRO_32,
	CHROMIUM_WEBVIEW_NATIVE_RELRO_64, clazzLoader);
	if (result != WebViewFactory.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;
	}

	/**
	* Fetch WebView's native library paths from {@param packageInfo}.
	*/
	static String[] getWebViewNativeLibraryPaths(PackageInfo packageInfo)
	throws WebViewFactory.MissingWebViewPackageException {
	ApplicationInfo ai = packageInfo.applicationInfo;
	final String nativeLibFileName = WebViewFactory.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 += "/" + nativeLibFileName;
	File f = new File(path32);
	if (!f.exists()) {
	path32 = getLoadFromApkPath(ai.sourceDir,
	Build.SUPPORTED_32_BIT_ABIS,
	nativeLibFileName);
	}
	}
	if (!TextUtils.isEmpty(path64)) {
	path64 += "/" + nativeLibFileName;
	File f = new File(path64);
	if (!f.exists()) {
	path64 = getLoadFromApkPath(ai.sourceDir,
	Build.SUPPORTED_64_BIT_ABIS,
	nativeLibFileName);
	}
	}

	if (DEBUG) Log.v(LOGTAG, "Native 32-bit lib: " + path32 + ", 64-bit lib: " + path64);
	return new String[] { path32, path64 };
	}

	private static String getLoadFromApkPath(String apkPath,
	String[] abiList,
	String nativeLibFileName)
	throws WebViewFactory.MissingWebViewPackageException {
	// 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 WebViewFactory.MissingWebViewPackageException(e);
	}
	return "";
	}

	/**
	* Sets the size of the memory area in which to store the relro section.
	*/
	private static void setWebViewZygoteVmSize(long vmSize) {
	SystemProperties.set(WebViewFactory.CHROMIUM_WEBVIEW_VMSIZE_SIZE_PROPERTY,
	Long.toString(vmSize));
	}

	static native boolean nativeReserveAddressSpace(long addressSpaceToReserve);
	static native boolean nativeCreateRelroFile(String lib32, String lib64,
	String relro32, String relro64);
	static native int nativeLoadWithRelroFile(String lib, String relro32, String relro64,
	ClassLoader clazzLoader);
	}