Files
jpexs-decompiler/src/com/jpexs/decompiler/flash/action/deobfuscation/ActionDeobfuscator.java
2014-08-23 20:53:30 +02:00

477 lines
21 KiB
Java

/*
* Copyright (C) 2010-2014 JPEXS
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
package com.jpexs.decompiler.flash.action.deobfuscation;
import com.jpexs.decompiler.flash.DisassemblyListener;
import com.jpexs.decompiler.flash.SWF;
import com.jpexs.decompiler.flash.SWFInputStream;
import com.jpexs.decompiler.flash.action.Action;
import com.jpexs.decompiler.flash.action.ActionList;
import com.jpexs.decompiler.flash.action.ActionListReader;
import com.jpexs.decompiler.flash.action.ActionLocalData;
import com.jpexs.decompiler.flash.action.model.DirectValueActionItem;
import com.jpexs.decompiler.flash.action.model.ReturnActionItem;
import com.jpexs.decompiler.flash.action.special.ActionEnd;
import com.jpexs.decompiler.flash.action.special.ActionStore;
import com.jpexs.decompiler.flash.action.swf4.ActionAdd;
import com.jpexs.decompiler.flash.action.swf4.ActionEquals;
import com.jpexs.decompiler.flash.action.swf4.ActionGetVariable;
import com.jpexs.decompiler.flash.action.swf4.ActionIf;
import com.jpexs.decompiler.flash.action.swf4.ActionJump;
import com.jpexs.decompiler.flash.action.swf4.ActionMultiply;
import com.jpexs.decompiler.flash.action.swf4.ActionNot;
import com.jpexs.decompiler.flash.action.swf4.ActionPush;
import com.jpexs.decompiler.flash.action.swf4.ActionSetVariable;
import com.jpexs.decompiler.flash.action.swf4.ActionSubtract;
import com.jpexs.decompiler.flash.action.swf4.ConstantIndex;
import com.jpexs.decompiler.flash.action.swf4.RegisterNumber;
import com.jpexs.decompiler.flash.action.swf5.ActionAdd2;
import com.jpexs.decompiler.flash.action.swf5.ActionBitAnd;
import com.jpexs.decompiler.flash.action.swf5.ActionBitLShift;
import com.jpexs.decompiler.flash.action.swf5.ActionBitOr;
import com.jpexs.decompiler.flash.action.swf5.ActionBitRShift;
import com.jpexs.decompiler.flash.action.swf5.ActionBitXor;
import com.jpexs.decompiler.flash.action.swf5.ActionCallFunction;
import com.jpexs.decompiler.flash.action.swf5.ActionConstantPool;
import com.jpexs.decompiler.flash.action.swf5.ActionDefineFunction;
import com.jpexs.decompiler.flash.action.swf5.ActionDefineLocal;
import com.jpexs.decompiler.flash.action.swf5.ActionModulo;
import com.jpexs.decompiler.flash.action.swf5.ActionPushDuplicate;
import com.jpexs.decompiler.flash.action.swf5.ActionReturn;
import com.jpexs.decompiler.flash.ecma.EcmaScript;
import com.jpexs.decompiler.flash.helpers.SWFDecompilerListener;
import com.jpexs.decompiler.graph.Graph;
import com.jpexs.decompiler.graph.GraphSourceItemContainer;
import com.jpexs.decompiler.graph.GraphTargetItem;
import com.jpexs.decompiler.graph.TranslateException;
import com.jpexs.decompiler.graph.TranslateStack;
import java.io.IOException;
import java.util.ArrayList;
import java.util.EmptyStackException;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.logging.Level;
import java.util.logging.Logger;
/**
*
* @author JPEXS
*/
public class ActionDeobfuscator implements SWFDecompilerListener {
private final int executionLimit = 30000;
@Override
public void actionListParsed(ActionList actions, SWF swf) {
combinePushs(actions);
Map<String, Object> fakeFunctions = getFakeFunctionResults(actions);
removeUnreachableActions(actions);
removeObfuscationIfs(actions, fakeFunctions);
removeUnreachableActions(actions);
removeZeroJumps(actions);
rereadActionList(actions, swf); // this call will fix the contant pool assigments
}
private void combinePushs(ActionList actions) {
for (int i = 0; i < actions.size() - 1; i++) {
Action action = actions.get(i);
Action action2 = actions.get(i + 1);
if (action instanceof ActionPush && action2 instanceof ActionPush) {
if (!actions.getReferencesFor(action2).hasNext()) {
ActionPush push = (ActionPush) action;
ActionPush push2 = (ActionPush) action2;
push.values.addAll(push2.values);
actions.remove(i + 1);
i--;
}
}
}
}
private boolean rereadActionList(ActionList actions, SWF swf) {
byte[] actionBytes = Action.actionsToBytes(actions, true, SWF.DEFAULT_VERSION);
try {
SWFInputStream rri = new SWFInputStream(swf, actionBytes);
ActionList newActions = ActionListReader.readActionList(new ArrayList<DisassemblyListener>(), rri, SWF.DEFAULT_VERSION, 0, actionBytes.length, "", -1);
actions.setActions(newActions);
} catch (IOException | InterruptedException ex) {
Logger.getLogger(ActionDeobfuscator.class.getName()).log(Level.SEVERE, null, ex);
}
return true;
}
private boolean removeUnreachableActions(ActionList actions) {
Set<Action> reachableActions = new HashSet<>();
Set<Action> processedActions = new HashSet<>();
reachableActions.add(actions.get(0));
boolean modified = true;
while (modified) {
modified = false;
for (int i = 0; i < actions.size(); i++) {
Action action = actions.get(i);
if (reachableActions.contains(action) && !processedActions.contains(action)) {
if (!action.isExit() && !(action instanceof ActionJump) && i != actions.size() - 1) {
Action next = actions.get(i + 1);
if (!reachableActions.contains(next)) {
reachableActions.add(next);
}
}
if (action instanceof ActionJump) {
ActionJump aJump = (ActionJump) action;
long ref = aJump.getAddress() + aJump.getTotalActionLength() + aJump.getJumpOffset();
Action target = actions.getByAddress(ref);
if (target != null && !reachableActions.contains(target)) {
reachableActions.add(target);
}
} else if (action instanceof ActionIf) {
ActionIf aIf = (ActionIf) action;
long ref = aIf.getAddress() + aIf.getTotalActionLength() + aIf.getJumpOffset();
Action target = actions.getByAddress(ref);
if (target != null && !reachableActions.contains(target)) {
reachableActions.add(target);
}
} else if (action instanceof ActionStore) {
ActionStore aStore = (ActionStore) action;
int storeSize = aStore.getStoreSize();
if (actions.size() > i + storeSize) {
Action target = actions.get(i + storeSize);
if (!reachableActions.contains(target)) {
reachableActions.add(target);
}
}
} else if (action instanceof GraphSourceItemContainer) {
GraphSourceItemContainer container = (GraphSourceItemContainer) action;
long ref = action.getAddress() + action.getTotalActionLength();
for (Long size : container.getContainerSizes()) {
ref += size;
Action target = actions.getByAddress(ref);
if (target != null && !reachableActions.contains(target)) {
reachableActions.add(target);
}
}
}
processedActions.add(action);
modified = true;
}
}
}
boolean result = false;
for (int i = 0; i < actions.size(); i++) {
if (!reachableActions.contains(actions.get(i))) {
actions.removeAction(i);
i--;
result = true;
}
}
return result;
}
private boolean removeZeroJumps(ActionList actions) {
boolean result = false;
for (int i = 0; i < actions.size(); i++) {
Action action = actions.get(i);
if (action instanceof ActionJump && ((ActionJump) action).getJumpOffset() == 0) {
actions.removeAction(i);
i--;
result = true;
}
}
return result;
}
private boolean removeObfuscationIfs(ActionList actions, Map<String, Object> fakeFunctions) {
if (actions.size() == 0) {
return false;
}
for (int i = 0; i < actions.size(); i++) {
ExecutionResult result = new ExecutionResult();
executeActions(actions, i, actions.size() - 1, result, fakeFunctions);
if (result.idx != -1) {
int newIstructionCount = 1; // jump
if (result.constantPool != null) {
newIstructionCount++;
}
if (!result.stack.isEmpty()) {
newIstructionCount++;
}
newIstructionCount += 2 * result.variables.size();
if (newIstructionCount * 2 < result.instructionsProcessed) {
Action target = actions.get(result.idx);
Action prevAction = actions.get(i);
if (result.constantPool != null) {
ActionConstantPool constantPool2 = new ActionConstantPool(new ArrayList<>(result.constantPool.constantPool));
actions.addAction(i++, constantPool2);
prevAction = constantPool2;
}
for (String variableName : result.variables.keySet()) {
Object value = result.variables.get(variableName);
ActionPush push = new ActionPush(variableName);
push.values.add(value);
push.setAddress(prevAction.getAddress());
actions.addAction(i++, push);
prevAction = push;
if (result.defines.contains(variableName)) {
ActionDefineLocal defineLocal = new ActionDefineLocal();
defineLocal.setAddress(prevAction.getAddress());
actions.addAction(i++, defineLocal);
prevAction = defineLocal;
} else {
ActionSetVariable setVariable = new ActionSetVariable();
setVariable.setAddress(prevAction.getAddress());
actions.addAction(i++, setVariable);
prevAction = setVariable;
}
}
if (!result.stack.isEmpty()) {
ActionPush push = new ActionPush(0);
push.values.clear();
for (GraphTargetItem graphTargetItem : result.stack) {
DirectValueActionItem dv = (DirectValueActionItem) graphTargetItem;
push.values.add(dv.value);
}
push.setAddress(prevAction.getAddress());
actions.addAction(i++, push);
prevAction = push;
}
ActionJump jump = new ActionJump(0);
jump.setAddress(prevAction.getAddress());
jump.setJumpOffset((int) (target.getAddress() - jump.getAddress() - jump.getTotalActionLength()));
actions.addAction(i++, jump);
return true;
}
}
}
return false;
}
private void executeActions(ActionList actions, int idx, int endIdx, ExecutionResult result, Map<String, Object> fakeFunctions) {
List<GraphTargetItem> output = new ArrayList<>();
ActionLocalData localData = new ActionLocalData();
FixItemCounterTranslateStack stack = new FixItemCounterTranslateStack();
int instructionsProcessed = 0;
ActionConstantPool constantPool = null;
try {
while (true) {
if (idx > endIdx) {
break;
}
Action action = actions.get(idx);
instructionsProcessed++;
if (instructionsProcessed > executionLimit) {
break;
}
/*System.out.print(action.getASMSource(actions, new ArrayList<Long>(), ScriptExportMode.PCODE));
for (int j = 0; j < stack.size(); j++) {
System.out.print(" '" + stack.get(j).getResult() + "'");
}
System.out.println();*/
if (action instanceof ActionConstantPool) {
constantPool = (ActionConstantPool) action;
}
if (action instanceof ActionDefineLocal) {
GraphTargetItem top = stack.pop();
String variableName = stack.peek().getResult().toString();
result.defines.add(variableName);
stack.push(top);
}
if (action instanceof ActionGetVariable) {
String variableName = stack.peek().getResult().toString();
if (!localData.variables.containsKey(variableName)) {
break;
}
}
if (action instanceof ActionCallFunction) {
String functionName = stack.pop().getResult().toString();
long numArgs = EcmaScript.toUint32(stack.pop().getResult());
if (numArgs == 0) {
if (fakeFunctions != null && fakeFunctions.containsKey(functionName)) {
stack.push(new DirectValueActionItem(fakeFunctions.get(functionName)));
} else {
break;
}
} else {
break;
}
} else {
action.translate(localData, stack, output, Graph.SOP_USE_STATIC, "");
}
if (!(action instanceof ActionPush
|| action instanceof ActionPushDuplicate
|| action instanceof ActionAdd
|| action instanceof ActionAdd2
|| action instanceof ActionSubtract
|| action instanceof ActionModulo
|| action instanceof ActionMultiply
|| action instanceof ActionBitXor
|| action instanceof ActionBitAnd
|| action instanceof ActionBitOr
|| action instanceof ActionBitLShift
|| action instanceof ActionBitRShift
|| action instanceof ActionDefineLocal
|| action instanceof ActionJump
|| action instanceof ActionGetVariable
|| action instanceof ActionSetVariable
|| action instanceof ActionEquals
|| action instanceof ActionNot
|| action instanceof ActionIf
|| action instanceof ActionConstantPool
|| action instanceof ActionCallFunction
|| action instanceof ActionReturn
|| action instanceof ActionEnd)) {
break;
}
if (action instanceof ActionPush) {
ActionPush push = (ActionPush) action;
boolean ok = true;
for (Object value : push.values) {
if (value instanceof ConstantIndex || value instanceof RegisterNumber) {
ok = false;
break;
}
}
if (!ok) {
break;
}
}
/*for (String variable : localData.variables.keySet()) {
System.out.println(Helper.byteArrToString(variable.getBytes()));
}*/
idx++;
if (action instanceof ActionJump) {
ActionJump jump = (ActionJump) action;
long address = jump.getAddress() + jump.getTotalActionLength() + jump.getJumpOffset();
idx = actions.indexOf(actions.getByAddress(address));
if (idx == -1) {
throw new TranslateException("Jump target not found: " + address);
}
}
if (action instanceof ActionIf) {
ActionIf aif = (ActionIf) action;
if (EcmaScript.toBoolean(stack.pop().getResult())) {
System.out.println("if true");
long address = aif.getAddress() + aif.getTotalActionLength() + aif.getJumpOffset();
idx = actions.indexOf(actions.getByAddress(address));
if (idx == -1) {
throw new TranslateException("If target not found: " + address);
}
}
}
if (action instanceof ActionDefineFunction) {
List<Action> lastActions = actions.getContainerLastActions(action);
int lastActionIdx = actions.indexOf(lastActions.get(0));
idx = lastActionIdx != -1 ? lastActionIdx + 1 : -1;
}
if (/*localData.variables.size() == 1 && */stack.allItemsFixed() || action instanceof ActionEnd) {
result.idx = idx == actions.size() ? idx - 1 : idx;
result.instructionsProcessed = instructionsProcessed;
result.constantPool = constantPool;
result.variables.clear();
for (String variableName : localData.variables.keySet()) {
Object value = localData.variables.get(variableName).getResult();
result.variables.put(variableName, value);
}
result.stack.clear();
result.stack.addAll(stack);
}
if (action instanceof ActionReturn) {
if (output.size() > 0) {
ReturnActionItem ret = (ReturnActionItem) output.get(output.size() - 1);
result.resultValue = ret.value.getResult();
}
break;
}
}
} catch (EmptyStackException | TranslateException | InterruptedException ex) {
}
}
private Map<String, Object> getFakeFunctionResults(ActionList actions) {
/*
DefineFunction "fakeName" 0 {
Push 1777
Return
}
*/
Map<String, Object> results = new HashMap<>();
for (int i = 0; i < actions.size(); i++) {
Action action = actions.get(i);
if (action instanceof ActionDefineFunction) {
ActionDefineFunction def = (ActionDefineFunction) action;
if (def.paramNames.isEmpty()) {
ExecutionResult result = new ExecutionResult();
List<Action> lastActions = actions.getContainerLastActions(action);
int lastActionIdx = actions.indexOf(lastActions.get(0));
executeActions(actions, i + 1, lastActionIdx, result, null);
if (result.resultValue != null) {
results.put(def.functionName, result.resultValue);
for (int j = i; j <= lastActionIdx; j++) {
actions.removeAction(i);
}
}
}
}
}
return results;
}
class ExecutionResult {
public int idx = -1;
public int instructionsProcessed = -1;
public ActionConstantPool constantPool;
public Map<String, Object> variables = new HashMap<>();
public Set<String> defines = new HashSet<>();
public TranslateStack stack = new TranslateStack();
public Object resultValue;
}
}