dorkbox.jna.ClassUtils Maven / Gradle / Ivy
/*
* Copyright 2016 dorkbox, llc
*
* 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 dorkbox.jna;
import java.lang.reflect.Method;
import java.util.HashMap;
import java.util.Map;
import java.util.concurrent.atomic.AtomicBoolean;
import com.sun.jna.JNIEnv;
import com.sun.jna.Library;
import com.sun.jna.Native;
import com.sun.jna.NativeLibrary;
import com.sun.jna.win32.StdCallFunctionMapper;
import dorkbox.os.OS;
// http://hg.openjdk.java.net/jdk/jdk10/file/b09e56145e11/src/java.base/share/native/libjava/ClassLoader.c
// http://hg.openjdk.java.net/jdk10/jdk10/jdk/file/777356696811/src/java.base/share/native/libjava/ClassLoader.c
// http://hg.openjdk.java.net/jdk9/jdk9/jdk/file/65464a307408/src/java.base/share/native/libjava/ClassLoader.c
// http://hg.openjdk.java.net/jdk8u/jdk8u/jdk/file/be698ac28848/src/share/native/java/lang/ClassLoader.c
// http://hg.openjdk.java.net/jdk7/jdk7/hotspot/file/tip/src/share/vm/prims/jvm.cpp
// objdump -T | grep foo
// otool -tvV | grep foo
/**
* Gives us the ability to inject bytes into the "normal" classloader, or directly into java's bootstrap classloader.
*
* When injecting into the bootstrap classloader, this COMPLETELY bypass all security checks, as it calls native methods directly via JNA.
*/
@SuppressWarnings({"WeakerAccess", "unchecked"})
public class ClassUtils {
private static final JVM libJvm;
// Note: this does not work in java8 x86 *on windows XP windows7, etc. It only works on x64
@SuppressWarnings("UnusedReturnValue")
public
interface JVM extends com.sun.jna.Library {
void JVM_DefineClass(JNIEnv env, String name, Object classLoader, byte[] buffer, int length, Object protectionDomain);
}
private static final String libName;
static {
if (OS.INSTANCE.isMacOsX()) {
if (OS.INSTANCE.getJavaVersion() < 7) {
libName = "JavaVM";
} else {
String javaLocation = System.getProperty("java.home");
// have to explicitly specify the JVM library via full path
// this is OK, because for java on MacOSX, this is the only location it can exist
libName = javaLocation + "/lib/server/libjvm.dylib";
}
}
else {
libName = "jvm";
}
// function name is SLIGHTLY different on windows x32 java builds.
// For actual name use: http://www.nirsoft.net/utils/dll_export_viewer.html
//noinspection rawtypes
Map options = new HashMap();
options.put(Library.OPTION_ALLOW_OBJECTS, Boolean.TRUE);
if (OS.INSTANCE.isWindows() && OS.INSTANCE.is32bit()) {
options.put(Library.OPTION_FUNCTION_MAPPER, new StdCallFunctionMapper() {
@Override
public
String getFunctionName(NativeLibrary library, Method method) {
String methodName = method.getName();
if (methodName.equals("JVM_DefineClass")) {
// specifically Oracle Java 32bit builds. Tested on XP and Win7
return "_JVM_DefineClass@24";
}
return methodName;
}
});
libJvm = Native.load(libName, JVM.class, options);
} else {
libJvm = Native.load(libName, JVM.class, options);
}
}
/**
* Defines a class in the current threads class-loader
*
* @param classBytes the bytes of the class to define
*/
public static
void defineClass(final byte[] classBytes) throws Exception {
java.lang.ClassLoader classLoader = Thread.currentThread().getContextClassLoader();
defineClass(classLoader, classBytes);
}
/**
* Inject class bytes directly into the bootstrap classloader.
*
* This is a VERY DANGEROUS method to use!
*
* @param classLoader the classLoader to use. null will use the BOOTSTRAP classloader
* @param classBytes the bytes to inject
*/
@SuppressWarnings("RedundantThrows")
public static
void defineClass(java.lang.ClassLoader classLoader, byte[] classBytes) throws Exception {
// inject into the FIRST JVM that are started by us (is USUALLY 1, but not always)
libJvm.JVM_DefineClass(JNIEnv.CURRENT, null, classLoader, classBytes, classBytes.length, null);
}
private static
AtomicBoolean loaded = new AtomicBoolean(false);
/**
* Finds the class in the specified classloader without the use of reflection
*/
public static Class findLoadedClass(ClassLoader classLoader, String className) {
// we rewrite the ClassFixer at runtime, as appropriate
if (!loaded.getAndSet(true)) {
// we do not have a dependency on javassist simply because we ALREADY know what the generated class bytes are (so there's no need)
// try {
// ClassPool pool = ClassPool.getDefault();
// CtClass dynamicClass = pool.makeClass("java.lang.ClassLoaderAccessor");
// CtMethod method = CtNewMethod.make("public static Class findLoadedClass(ClassLoader classLoader, String className) { " +
// "return classLoader.findLoadedClass(className);" +
// "}", dynamicClass);
// dynamicClass.addMethod(method);
// dynamicClass.setModifiers(dynamicClass.getModifiers() & ~Modifier.STATIC);
//
// final byte[] classLoaderAccessorBytes = dynamicClass.toBytecode();
// Sys.printArray(classLoaderAccessorBytes);
// } catch (Exception e) {
// e.printStackTrace();
// }
//
byte[] classLoaderAccessorBytes = {
-54,-2,-70,-66,0,0,0,52,0,19,1,0,29,106,97,118,97,47,108,97,110,103,47,67,108,97,115,115,76,111,97,100,101,114,65,99,99,101,115,115,111,
114,7,0,1,1,0,16,106,97,118,97,47,108,97,110,103,47,79,98,106,101,99,116,7,0,3,1,0,10,83,111,117,114,99,101,70,105,108,101,1,
0,24,67,108,97,115,115,76,111,97,100,101,114,65,99,99,101,115,115,111,114,46,106,97,118,97,1,0,15,102,105,110,100,76,111,97,100,101,100,67,
108,97,115,115,1,0,60,40,76,106,97,118,97,47,108,97,110,103,47,67,108,97,115,115,76,111,97,100,101,114,59,76,106,97,118,97,47,108,97,110,
103,47,83,116,114,105,110,103,59,41,76,106,97,118,97,47,108,97,110,103,47,67,108,97,115,115,59,1,0,21,106,97,118,97,47,108,97,110,103,47,
67,108,97,115,115,76,111,97,100,101,114,7,0,9,1,0,37,40,76,106,97,118,97,47,108,97,110,103,47,83,116,114,105,110,103,59,41,76,106,97,
118,97,47,108,97,110,103,47,67,108,97,115,115,59,12,0,7,0,11,10,0,10,0,12,1,0,4,67,111,100,101,1,0,6,60,105,110,105,116,62,
1,0,3,40,41,86,12,0,15,0,16,10,0,4,0,17,0,33,0,2,0,4,0,0,0,0,0,2,0,9,0,7,0,8,0,1,0,14,0,0,
0,18,0,2,0,2,0,0,0,6,42,43,-74,0,13,-80,0,0,0,0,0,1,0,15,0,16,0,1,0,14,0,0,0,17,0,1,0,1,0,0,
0,5,42,-73,0,18,-79,0,0,0,0,0,1,0,5,0,0,0,2,0,6};
try {
ClassUtils.defineClass(null, classLoaderAccessorBytes);
} catch (Exception e) {
// we are fully expecting this to be available. completely die if it's not!
throw new RuntimeException(e);
}
// try {
// ClassPool pool = ClassPool.getDefault();
// CtClass classFixer = pool.get("dorkbox.jna.ClassLoaderAccessory");
// CtMethod ctMethod = classFixer.getDeclaredMethod("findLoadedClass");
// ctMethod.setBody("{" +
// "return java.lang.ClassLoaderAccessor.findLoadedClass($1, $2);" +
// "}");
//
// // perform pre-verification for the modified method
// ctMethod.getMethodInfo().rebuildStackMapForME(pool);
//
// final byte[] classFixerBytes = classFixer.toBytecode();
// Sys.printArray(classFixerBytes);
// } catch (Exception e) {
// e.printStackTrace();
// }
byte[] classFixerBytes = {
-54,-2,-70,-66,0,0,0,52,0,22,1,0,32,100,111,114,107,98,111,120,47,106,110,97,47,67,108,97,115,115,76,111,97,100,101,114,65,99,99,101,115,
115,111,114,121,7,0,1,1,0,16,106,97,118,97,47,108,97,110,103,47,79,98,106,101,99,116,7,0,3,1,0,6,60,105,110,105,116,62,1,0,
3,40,41,86,1,0,4,67,111,100,101,1,0,15,76,105,110,101,78,117,109,98,101,114,84,97,98,108,101,1,0,18,76,111,99,97,108,86,97,114,
105,97,98,108,101,84,97,98,108,101,1,0,4,116,104,105,115,1,0,34,76,100,111,114,107,98,111,120,47,106,110,97,47,67,108,97,115,115,76,111,
97,100,101,114,65,99,99,101,115,115,111,114,121,59,12,0,5,0,6,10,0,4,0,12,1,0,15,102,105,110,100,76,111,97,100,101,100,67,108,97,
115,115,1,0,60,40,76,106,97,118,97,47,108,97,110,103,47,67,108,97,115,115,76,111,97,100,101,114,59,76,106,97,118,97,47,108,97,110,103,47,
83,116,114,105,110,103,59,41,76,106,97,118,97,47,108,97,110,103,47,67,108,97,115,115,59,1,0,29,106,97,118,97,47,108,97,110,103,47,67,108,
97,115,115,76,111,97,100,101,114,65,99,99,101,115,115,111,114,7,0,16,12,0,14,0,15,10,0,17,0,18,1,0,10,83,111,117,114,99,101,70,
105,108,101,1,0,25,67,108,97,115,115,76,111,97,100,101,114,65,99,99,101,115,115,111,114,121,46,106,97,118,97,0,32,0,2,0,4,0,0,0,
0,0,2,0,0,0,5,0,6,0,1,0,7,0,0,0,47,0,1,0,1,0,0,0,5,42,-73,0,13,-79,0,0,0,2,0,8,0,0,0,6,
0,1,0,0,0,3,0,9,0,0,0,12,0,1,0,0,0,5,0,10,0,11,0,0,0,12,0,14,0,15,0,1,0,7,0,0,0,18,0,2,
0,2,0,0,0,6,42,43,-72,0,19,-80,0,0,0,0,0,1,0,20,0,0,0,2,0,21};
try {
// specifically not in the bootstrap classloader -- but instead in the classloader initially searched (which might be the wrong one)
ClassUtils.defineClass(classLoader, classFixerBytes);
} catch (Exception e) {
// we are fully expecting this to be available. completely die if it's not!
throw new RuntimeException(e);
}
}
return ClassLoaderAccessory.findLoadedClass(classLoader, className);
}
/**
* Checks if the specified classloader has the class loaded or not, without the use of reflection
*/
public static boolean isClassLoaded(ClassLoader classLoader, String className) {
return null != findLoadedClass(classLoader, className);
}
}