Main.java revision 5a61bb7969347ffe8e0bf4f4dff841cc6c21ed85
1/* 2 * Copyright (C) 2017 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 17import dalvik.system.InMemoryDexClassLoader; 18import dalvik.system.PathClassLoader; 19import java.io.File; 20import java.io.InputStream; 21import java.lang.reflect.Constructor; 22import java.lang.reflect.Method; 23import java.nio.ByteBuffer; 24import java.nio.file.Files; 25import java.util.Arrays; 26import java.util.zip.ZipEntry; 27import java.util.zip.ZipFile; 28 29public class Main { 30 public static void main(String[] args) throws Exception { 31 System.loadLibrary(args[0]); 32 prepareNativeLibFileName(args[0]); 33 34 // Enable hidden API checks in case they are disabled by default. 35 init(); 36 37 // Run test with both parent and child dex files loaded with class loaders. 38 // The expectation is that hidden members in parent should be visible to 39 // the child. 40 doTest(false, false); 41 42 // Now append parent dex file to boot class path and run again. This time 43 // the child dex file should not be able to access private APIs of the parent. 44 appendToBootClassLoader(DEX_PARENT_BOOT); 45 doTest(true, false); 46 47 // And finally append to child to boot class path as well. With both in the 48 // boot class path, access should be granted. 49 appendToBootClassLoader(DEX_CHILD); 50 doTest(true, true); 51 52 System.out.println("Done"); 53 } 54 55 private static void doTest(boolean parentInBoot, boolean childInBoot) throws Exception { 56 // Load parent dex if it is not in boot class path. 57 ClassLoader parentLoader = null; 58 if (parentInBoot) { 59 parentLoader = BOOT_CLASS_LOADER; 60 } else { 61 parentLoader = new PathClassLoader(DEX_PARENT, ClassLoader.getSystemClassLoader()); 62 } 63 64 // Load child dex if it is not in boot class path. 65 ClassLoader childLoader = null; 66 if (childInBoot) { 67 if (parentLoader != BOOT_CLASS_LOADER) { 68 throw new IllegalStateException( 69 "DeclaringClass must be in parent class loader of CallingClass"); 70 } 71 childLoader = BOOT_CLASS_LOADER; 72 } else { 73 childLoader = new InMemoryDexClassLoader(readDexFile(DEX_CHILD), parentLoader); 74 } 75 76 // Create a unique copy of the native library. Each shared library can only 77 // be loaded once, but for some reason even classes from a class loader 78 // cannot register their native methods against symbols in a shared library 79 // loaded by their parent class loader. 80 String nativeLibCopy = createNativeLibCopy(parentInBoot, childInBoot); 81 82 // Invoke ChildClass.runTest 83 Class.forName("ChildClass", true, childLoader) 84 .getDeclaredMethod("runTest", String.class, Boolean.TYPE, Boolean.TYPE) 85 .invoke(null, nativeLibCopy, parentInBoot, childInBoot); 86 } 87 88 // Routine which tries to figure out the absolute path of our native library. 89 private static void prepareNativeLibFileName(String arg) throws Exception { 90 String libName = System.mapLibraryName(arg); 91 Method libPathsMethod = Runtime.class.getDeclaredMethod("getLibPaths"); 92 libPathsMethod.setAccessible(true); 93 String[] libPaths = (String[]) libPathsMethod.invoke(Runtime.getRuntime()); 94 nativeLibFileName = null; 95 for (String p : libPaths) { 96 String candidate = p + libName; 97 if (new File(candidate).exists()) { 98 nativeLibFileName = candidate; 99 break; 100 } 101 } 102 if (nativeLibFileName == null) { 103 throw new IllegalStateException("Didn't find " + libName + " in " + 104 Arrays.toString(libPaths)); 105 } 106 } 107 108 // Helper to read dex file into memory. 109 private static ByteBuffer readDexFile(String jarFileName) throws Exception { 110 ZipFile zip = new ZipFile(new File(jarFileName)); 111 ZipEntry entry = zip.getEntry("classes.dex"); 112 InputStream is = zip.getInputStream(entry); 113 int offset = 0; 114 int size = (int) entry.getSize(); 115 ByteBuffer buffer = ByteBuffer.allocate(size); 116 while (is.available() > 0) { 117 is.read(buffer.array(), offset, size - offset); 118 } 119 is.close(); 120 zip.close(); 121 return buffer; 122 } 123 124 // Copy native library to a new file with a unique name so it does not conflict 125 // with other loaded instance of the same binary file. 126 private static String createNativeLibCopy(boolean parentInBoot, boolean childInBoot) 127 throws Exception { 128 String tempFileName = System.mapLibraryName( 129 "hiddenapitest_" + (parentInBoot ? "1" : "0") + (childInBoot ? "1" : "0")); 130 File tempFile = new File(System.getenv("DEX_LOCATION"), tempFileName); 131 Files.copy(new File(nativeLibFileName).toPath(), tempFile.toPath()); 132 return tempFile.getAbsolutePath(); 133 } 134 135 private static String nativeLibFileName; 136 137 private static final String DEX_PARENT = 138 new File(System.getenv("DEX_LOCATION"), "674-hiddenapi.jar").getAbsolutePath(); 139 private static final String DEX_PARENT_BOOT = 140 new File(new File(System.getenv("DEX_LOCATION"), "res"), "boot.jar").getAbsolutePath(); 141 private static final String DEX_CHILD = 142 new File(System.getenv("DEX_LOCATION"), "674-hiddenapi-ex.jar").getAbsolutePath(); 143 144 private static ClassLoader BOOT_CLASS_LOADER = Object.class.getClassLoader(); 145 146 private static native void appendToBootClassLoader(String dexPath); 147 private static native void init(); 148} 149