/*
* JBoss, Home of Professional Open Source
* Copyright 2009, Red Hat Middleware LLC, and individual contributors
* by the @authors tag. See the copyright.txt in the distribution for a
* full listing of individual contributors.
*
* This is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This software is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*
* @authors Andrew Dinn
*/
package org.jboss.byteman.agent.adapter;
import org.objectweb.asm.MethodVisitor;
import org.objectweb.asm.Label;
import org.objectweb.asm.Opcodes;
import org.jboss.byteman.rule.type.Type;
import org.jboss.byteman.rule.binding.Bindings;
import org.jboss.byteman.rule.binding.Binding;
import org.jboss.byteman.agent.Transformer;
import org.jboss.byteman.agent.TransformContext;
import org.jboss.byteman.agent.LocationType;
import java.util.*;
/**
* class which provides base functionality extended by all the location-specific method check adapters
*/
public class RuleCheckMethodAdapter extends RuleMethodAdapter {
RuleCheckMethodAdapter(MethodVisitor mv, TransformContext transformContext, int access, String name, String descriptor)
{
super(mv, transformContext, access, name, descriptor);
this.triggerPoints = null;
}
protected void setTriggerPoint()
{
if (triggerPoints == null) {
triggerPoints = new ArrayList<Label>();
}
Label triggerLabel = new Label();
triggerPoints.add(triggerLabel);
this.visitLabel(triggerLabel);
}
boolean isTriggerPoint()
{
return (triggerPoints != null);
}
protected boolean checkBindings()
{
if (!isTriggerPoint()) {
return false;
}
Bindings bindings = rule.getBindings();
Iterator<Binding> bindingIter = bindings.iterator();
List<String> parameterTypenames = Type.parseMethodDescriptor(descriptor, true);
int parameterCount = parameterTypenames.size() - 1; // allows for return type
// make sure all entries are valid
while (bindingIter.hasNext()) {
Binding binding = bindingIter.next();
if (binding.isRecipient()) {
if ((access & Opcodes.ACC_STATIC) != 0) {
if (Transformer.isVerbose()) {
System.out.println("RuleCheckMethodAdapter.checkBindings : found invalid recipient binding " + binding + " checking static method " + name + descriptor);
}
return false;
}
} else if (binding.isParam()) {
int idx = binding.getIndex();
if (idx > parameterCount) {
// parameter out of range
if (Transformer.isVerbose()) {
System.out.println("RuleCheckMethodAdapter.checkBindings : found out of range parameter binding " + binding + " checking method " + name + descriptor);
}
return false;
} else {
binding.setDescriptor(parameterTypenames.get(idx - 1));
}
} else if (binding.isReturn()) {
// this is a valid reference in an AT EXIT rule and in an AFTER INVOKE
LocationType locationType = rule.getTargetLocation().getLocationType();
if (locationType != LocationType.EXIT && locationType != LocationType.INVOKE_COMPLETED) {
System.out.println("RuleCheckMethodAdapter.checkBindings : found return value binding $! in rule which is neither AT EXIT nor AFTER INVOKE " + rule.getName());
return false;
}
} else if (binding.isThrowable()) {
// we can only allow reference to the current throwable in an AT THROW rule
if (rule.getTargetLocation().getLocationType() != LocationType.THROW) {
System.out.println("RuleCheckMethodAdapter.checkBindings : found throwable value binding $^ in non-THROW rule " + rule.getName());
return false;
}
// we will need to set the descriptor at some point
} else if (binding.isParamArray()) {
// this is ok
} else if (binding.isParamCount()) {
// this is ok
} else if (binding.isInvokeParamArray()) {
// we can only allow reference to the invoked method parameters in an AT INVOKE rule
if (rule.getTargetLocation().getLocationType() != LocationType.INVOKE) {
System.out.println("RuleCheckMethodAdapter.checkBindings : found invoke parameter array binding $@ in non-AT INVOKE rule " + rule.getName());
return false;
}
} else if (binding.isLocalVar()){
// make sure we have a local variable with the correct name
String localVarName = binding.getName().substring(1);
List<LocalVar> localVars = lookup(localVarName);
if (localVars == null || localVars.isEmpty()) {
if (Transformer.isVerbose()) {
System.out.println("RuleCheckMethodAdapter.checkBindings : unknown local variable binding " + binding + " checking method " + name + descriptor);
}
return false;
} else {
String descriptor = null;
int index = -1;
Iterator<Label> labelIter = triggerPoints.iterator();
while (labelIter.hasNext()) {
int triggerPos = labelIter.next().getOffset();
boolean found = false;
Iterator<LocalVar> localVarIter = localVars.iterator();
while (localVarIter.hasNext()) {
LocalVar localVar = localVarIter.next();
int start = localVar.start.getOffset();
int end = localVar.end.getOffset();
if (start <= triggerPos && triggerPos < end) {
// only accept if the descriptor and index are the same or are not yet set
if (descriptor == null && index == -1) {
descriptor = localVar.desc;
index = localVar.index;
found = true;
} else if (descriptor.equals(localVar.desc) && index == localVar.index) {
found = true;
}
// terminate the loop here
break;
}
}
// if there was no variable for this trigger point then fail
if (!found) {
if (Transformer.isVerbose()) {
System.out.println("RuleCheckMethodAdapter.checkBindings : invalid local variable binding " + binding + " checking method " + name + descriptor);
}
return false;
}
}
// if we got here then we have a unique local var descriptor and index for
// all trigger points so update the binding
binding.setDescriptor(Type.parseFieldDescriptor(descriptor));
binding.setLocalIndex(index);
}
}
}
// ok all local vars and params are accounted for so return true
return true;
}
private List<Label> triggerPoints;
}