/*
* Copyright 2015 the original author or authors.
* @https://github.com/scouter-project/scouter
*
* 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 scouter.agent.asm;
import java.util.List;
import scouter.agent.ClassDesc;
import scouter.agent.Configure;
import scouter.agent.asm.util.AsmUtil;
import scouter.agent.asm.util.HookingSet;
import scouter.agent.trace.TraceMain;
import scouter.org.objectweb.asm.ClassVisitor;
import scouter.org.objectweb.asm.MethodVisitor;
import scouter.org.objectweb.asm.Opcodes;
import scouter.org.objectweb.asm.Type;
import scouter.org.objectweb.asm.commons.LocalVariablesSorter;
public class CapReturnASM implements IASM, Opcodes {
private List< HookingSet> target = HookingSet.getHookingMethodSet(Configure.getInstance().hook_return_patterns);
public ClassVisitor transform(ClassVisitor cv, String className, ClassDesc classDesc) {
if (Configure.getInstance()._hook_cap_enabled == false) {
return cv;
}
for (int i = 0; i < target.size(); i++) {
HookingSet mset = target.get(i);
if (mset.classMatch.include(className)) {
return new CapReturnCV(cv, mset, className);
}
}
return cv;
}
}
// ///////////////////////////////////////////////////////////////////////////
class CapReturnCV extends ClassVisitor implements Opcodes {
public String className;
private HookingSet mset;
public CapReturnCV(ClassVisitor cv, HookingSet mset, String className) {
super(ASM4, cv);
this.mset = mset;
this.className = className;
}
@Override
public MethodVisitor visitMethod(int access, String name, String desc, String signature, String[] exceptions) {
MethodVisitor mv = super.visitMethod(access, name, desc, signature, exceptions);
if (mv == null || mset.isA(name, desc) == false) {
return mv;
}
if(AsmUtil.isSpecial(name)){
return mv;
}
return new CapReturnMV(access, desc, mv, className, name, desc,(access & ACC_STATIC) != 0);
}
}
// ///////////////////////////////////////////////////////////////////////////
class CapReturnMV extends LocalVariablesSorter implements Opcodes {
private static final String CLASS = TraceMain.class.getName().replace('.', '/');
private static final String METHOD = "capReturn";
private static final String SIGNATURE = "(Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;Ljava/lang/Object;Ljava/lang/Object;)V";
private Type returnType;
private String className;
private String methodName;
private String methodDesc;
private boolean isStatic;
public CapReturnMV(int access, String desc, MethodVisitor mv,
String classname,
String methodname,
String methoddesc, boolean isStatic) {
super(ASM4, access, desc, mv);
this.returnType = Type.getReturnType(desc);
this.className = classname;
this.methodName = methodname;
this.methodDesc = methoddesc;
this.isStatic = isStatic;
}
@Override
public void visitInsn(int opcode) {
if ((opcode >= IRETURN && opcode <= RETURN)) {
capReturn();
}
mv.visitInsn(opcode);
}
private void capReturn() {
Type tp = returnType;
if (tp == null || tp.equals(Type.VOID_TYPE)) {
pushCommon();
mv.visitInsn(ACONST_NULL);
mv.visitMethodInsn(Opcodes.INVOKESTATIC, CLASS, METHOD, SIGNATURE,false);
return;
}
int i = newLocal(tp);
switch (tp.getSort()) {
case Type.BOOLEAN:
mv.visitVarInsn(Opcodes.ISTORE, i);
mv.visitVarInsn(Opcodes.ILOAD, i);
pushCommon();
mv.visitVarInsn(Opcodes.ILOAD, i);
mv.visitMethodInsn(Opcodes.INVOKESTATIC, "java/lang/Boolean", "valueOf", "(Z)Ljava/lang/Boolean;",false);
break;
case Type.BYTE:
mv.visitVarInsn(Opcodes.ISTORE, i);
mv.visitVarInsn(Opcodes.ILOAD, i);
pushCommon();
mv.visitVarInsn(Opcodes.ILOAD, i);
mv.visitMethodInsn(Opcodes.INVOKESTATIC, "java/lang/Byte", "valueOf", "(B)Ljava/lang/Byte;",false);
break;
case Type.CHAR:
mv.visitVarInsn(Opcodes.ISTORE, i);
mv.visitVarInsn(Opcodes.ILOAD, i);
pushCommon();
mv.visitVarInsn(Opcodes.ILOAD, i);
mv.visitMethodInsn(Opcodes.INVOKESTATIC, "java/lang/Character", "valueOf", "(C)Ljava/lang/Character;",false);
break;
case Type.SHORT:
mv.visitVarInsn(Opcodes.ISTORE, i);
mv.visitVarInsn(Opcodes.ILOAD, i);
pushCommon();
mv.visitVarInsn(Opcodes.ILOAD, i);
mv.visitMethodInsn(Opcodes.INVOKESTATIC, "java/lang/Short", "valueOf", "(S)Ljava/lang/Short;",false);
break;
case Type.INT:
mv.visitVarInsn(Opcodes.ISTORE, i);
mv.visitVarInsn(Opcodes.ILOAD, i);
pushCommon();
mv.visitVarInsn(Opcodes.ILOAD, i);
mv.visitMethodInsn(Opcodes.INVOKESTATIC, "java/lang/Integer", "valueOf", "(I)Ljava/lang/Integer;",false);
break;
case Type.LONG:
mv.visitVarInsn(Opcodes.LSTORE, i);
mv.visitVarInsn(Opcodes.LLOAD, i);
pushCommon();
mv.visitVarInsn(Opcodes.LLOAD, i);
mv.visitMethodInsn(Opcodes.INVOKESTATIC, "java/lang/Long", "valueOf", "(J)Ljava/lang/Long;",false);
break;
case Type.FLOAT:
mv.visitVarInsn(Opcodes.FSTORE, i);
mv.visitVarInsn(Opcodes.FLOAD, i);
pushCommon();
mv.visitVarInsn(Opcodes.FLOAD, i);
mv.visitMethodInsn(Opcodes.INVOKESTATIC, "java/lang/Float", "valueOf", "(F)Ljava/lang/Float;",false);
break;
case Type.DOUBLE:
mv.visitVarInsn(Opcodes.DSTORE, i);
mv.visitVarInsn(Opcodes.DLOAD, i);
pushCommon();
mv.visitVarInsn(Opcodes.DLOAD, i);
mv.visitMethodInsn(Opcodes.INVOKESTATIC, "java/lang/Double", "valueOf", "(D)Ljava/lang/Double;",false);
break;
default:
mv.visitVarInsn(Opcodes.ASTORE, i);
mv.visitVarInsn(Opcodes.ALOAD, i);
pushCommon();
mv.visitVarInsn(Opcodes.ALOAD, i);
}
mv.visitMethodInsn(Opcodes.INVOKESTATIC, CLASS, METHOD, SIGNATURE,false);
}
private void pushCommon() {
AsmUtil.PUSH(mv, className);
AsmUtil.PUSH(mv, methodName);
AsmUtil.PUSH(mv, methodDesc);
if (isStatic) {
AsmUtil.PUSHNULL(mv);
} else {
mv.visitVarInsn(Opcodes.ALOAD, 0);
}
}
}