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 
17 import art.Redefinition;
18 
19 import java.lang.reflect.*;
20 import java.util.Base64;
21 import java.util.concurrent.CountDownLatch;
22 import java.util.function.Consumer;
23 
24 class Main {
25   public static String TEST_NAME = "1950-unprepared-transform";
26 
27   // Base 64 encoding of the following class:
28   //
29   // public class Transform {
30   //   public String toString() {
31   //     return "Transformed object!";
32   //   }
33   // }
34   public static final byte[] CLASS_BYTES = Base64.getDecoder().decode(
35     "yv66vgAAADQAEQoABAANCAAOBwAPBwAQAQAGPGluaXQ+AQADKClWAQAEQ29kZQEAD0xpbmVOdW1i" +
36     "ZXJUYWJsZQEACHRvU3RyaW5nAQAUKClMamF2YS9sYW5nL1N0cmluZzsBAApTb3VyY2VGaWxlAQAO" +
37     "VHJhbnNmb3JtLmphdmEMAAUABgEAE1RyYW5zZm9ybWVkIG9iamVjdCEBAAlUcmFuc2Zvcm0BABBq" +
38     "YXZhL2xhbmcvT2JqZWN0ACEAAwAEAAAAAAACAAEABQAGAAEABwAAAB0AAQABAAAABSq3AAGxAAAA" +
39     "AQAIAAAABgABAAAAEgABAAkACgABAAcAAAAbAAEAAQAAAAMSArAAAAABAAgAAAAGAAEAAAAUAAEA" +
40     "CwAAAAIADA==");
41 
42   public static final byte[] DEX_BYTES = Base64.getDecoder().decode(
43     "ZGV4CjAzOACaXU/P8oJOECPrdN1Cu9/ob2cUb2vOKxqYAgAAcAAAAHhWNBIAAAAAAAAAABACAAAK" +
44     "AAAAcAAAAAQAAACYAAAAAgAAAKgAAAAAAAAAAAAAAAMAAADAAAAAAQAAANgAAACgAQAA+AAAADAB" +
45     "AAA4AQAAOwEAAEgBAABcAQAAcAEAAIABAACVAQAAmAEAAKIBAAACAAAAAwAAAAQAAAAHAAAAAQAA" +
46     "AAIAAAAAAAAABwAAAAMAAAAAAAAAAAABAAAAAAAAAAAACAAAAAEAAQAAAAAAAAAAAAEAAAABAAAA" +
47     "AAAAAAUAAAAAAAAAAAIAAAAAAAACAAEAAAAAACwBAAADAAAAGgAGABEAAAABAAEAAQAAACgBAAAE" +
48     "AAAAcBACAAAADgASAA4AFAAOAAY8aW5pdD4AAUwAC0xUcmFuc2Zvcm07ABJMamF2YS9sYW5nL09i" +
49     "amVjdDsAEkxqYXZhL2xhbmcvU3RyaW5nOwAOVHJhbnNmb3JtLmphdmEAE1RyYW5zZm9ybWVkIG9i" +
50     "amVjdCEAAVYACHRvU3RyaW5nAFx+fkQ4eyJtaW4tYXBpIjoyNywic2hhLTEiOiI3YTdjNDlhY2Nj" +
51     "NTkzNTIyNzY4MTY3MThhNGM3YWU1MmY5NjgzZjk5IiwidmVyc2lvbiI6InYxLjIuNC1kZXYifQAA" +
52     "AAEBAIGABJACAQH4AQAACwAAAAAAAAABAAAAAAAAAAEAAAAKAAAAcAAAAAIAAAAEAAAAmAAAAAMA" +
53     "AAACAAAAqAAAAAUAAAADAAAAwAAAAAYAAAABAAAA2AAAAAEgAAACAAAA+AAAAAMgAAACAAAAKAEA" +
54     "AAIgAAAKAAAAMAEAAAAgAAABAAAAAAIAAAAQAAABAAAAEAIAAA==");
55 
setupClassLoadHook(Thread target)56   public static native void setupClassLoadHook(Thread target);
clearClassLoadHook(Thread target)57   public static native void clearClassLoadHook(Thread target);
58   private static Consumer<Class<?>> doRedefine = null;
59 
doClassLoad(Class<?> c)60   public static void doClassLoad(Class<?> c) {
61     try {
62       if (c.getName().equals("Transform")) {
63         Redefinition.addCommonTransformationResult("Transform", CLASS_BYTES, DEX_BYTES);
64         doRedefine.accept(c);
65         System.out.println("retransformClasses on an unprepared class succeeded");
66       }
67     } catch (Throwable e) {
68       System.out.println("Trying to redefine: " + c + ". " +
69           "Caught error " + e.getClass() + ": " + e.getMessage());
70     }
71   }
72 
getClassLoaderFor(String location)73   public static ClassLoader getClassLoaderFor(String location) throws Exception {
74     try {
75       Class<?> class_loader_class = Class.forName("dalvik.system.PathClassLoader");
76       Constructor<?> ctor = class_loader_class.getConstructor(String.class, ClassLoader.class);
77       /* on Dalvik, this is a DexFile; otherwise, it's null */
78       return (ClassLoader)ctor.newInstance(location + "/" + TEST_NAME + "-ex.jar",
79                                            Main.class.getClassLoader());
80     } catch (ClassNotFoundException e) {
81       // Running on RI. Use URLClassLoader.
82       return new java.net.URLClassLoader(
83           new java.net.URL[] { new java.net.URL("file://" + location + "/classes-ex/") });
84     }
85   }
86 
testCurrentThread()87   public static void testCurrentThread() throws Throwable {
88     System.out.println("Redefine in ClassLoad on current thread.");
89     doRedefine = (c) -> { Redefinition.doCommonClassRetransformation(c); };
90     ClassLoader new_loader = getClassLoaderFor(System.getenv("DEX_LOCATION"));
91     Class<?> klass = (Class<?>)new_loader.loadClass("Transform");
92     if (klass == null) {
93       throw new AssertionError("loadClass failed");
94     }
95     Object o = klass.newInstance();
96     System.out.println("Object out is: " + o);
97   }
98 
testRemoteThread()99   public static void testRemoteThread() throws Throwable {
100     System.out.println("Redefine during ClassLoad on another thread.");
101     final Class[] loaded = new Class[] { null, };
102     final CountDownLatch gotClass = new CountDownLatch(1);
103     final CountDownLatch wokeUp = new CountDownLatch(1);
104     Thread redef_thread = new Thread(() -> {
105       try {
106         gotClass.await();
107         wokeUp.countDown();
108         // This will wait until the otehr thread returns so we need to wake up the other thread
109         // first.
110         Redefinition.doCommonClassRetransformation(loaded[0]);
111       } catch (Exception e) {
112         throw new Error("Failed to do redef!", e);
113       }
114     });
115     redef_thread.start();
116     doRedefine = (c) -> {
117       try {
118         loaded[0] = c;
119         gotClass.countDown();
120         wokeUp.await();
121         // Let the other thread do some stuff.
122         Thread.sleep(5000);
123       } catch (Exception e) {
124         throw new Error("Failed to do redef!", e);
125       }
126     };
127     ClassLoader new_loader = getClassLoaderFor(System.getenv("DEX_LOCATION"));
128     Class<?> klass = (Class<?>)new_loader.loadClass("Transform");
129     if (klass == null) {
130       throw new AssertionError("loadClass failed");
131     }
132     Object o = klass.newInstance();
133     System.out.println("Object out is: " + o);
134     redef_thread.join();
135     System.out.println("Redefinition thread finished.");
136   }
137 
main(String[] args)138   public static void main(String[] args) {
139     // make sure we can do the transform.
140     Redefinition.setTestConfiguration(Redefinition.Config.COMMON_RETRANSFORM);
141     Redefinition.setPopRetransformations(false);
142     Redefinition.enableCommonRetransformation(true);
143     setupClassLoadHook(Thread.currentThread());
144     try {
145       testCurrentThread();
146       testRemoteThread();
147     } catch (Throwable e) {
148       System.out.println(e.toString());
149       e.printStackTrace(System.out);
150     }
151     clearClassLoadHook(Thread.currentThread());
152   }
153 }
154