| /* |
| * ProGuard -- shrinking, optimization, obfuscation, and preverification |
| * of Java bytecode. |
| * |
| * Copyright (c) 2002-2011 Eric Lafortune (eric@graphics.cornell.edu) |
| * |
| * 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 2 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, write to the Free Software Foundation, Inc., |
| * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| */ |
| package proguard.obfuscate; |
| |
| import proguard.classfile.*; |
| import proguard.classfile.util.*; |
| import proguard.classfile.visitor.MemberVisitor; |
| |
| import java.util.*; |
| |
| /** |
| * This MemberVisitor obfuscates all class members that it visits. |
| * It uses names from the given name factory. At the same time, it avoids names |
| * from the given descriptor map. |
| * <p> |
| * The class members must have been linked before applying this visitor. |
| * |
| * @see MethodLinker |
| * |
| * @author Eric Lafortune |
| */ |
| public class MemberObfuscator |
| extends SimplifiedVisitor |
| implements MemberVisitor |
| { |
| private final boolean allowAggressiveOverloading; |
| private final NameFactory nameFactory; |
| private final Map descriptorMap; |
| |
| |
| /** |
| * Creates a new MemberObfuscator. |
| * @param allowAggressiveOverloading a flag that specifies whether class |
| * members can be overloaded aggressively. |
| * @param nameFactory the factory that can produce |
| * obfuscated member names. |
| * @param descriptorMap the map of descriptors to |
| * [new name - old name] maps. |
| */ |
| public MemberObfuscator(boolean allowAggressiveOverloading, |
| NameFactory nameFactory, |
| Map descriptorMap) |
| { |
| this.allowAggressiveOverloading = allowAggressiveOverloading; |
| this.nameFactory = nameFactory; |
| this.descriptorMap = descriptorMap; |
| } |
| |
| |
| // Implementations for MemberVisitor. |
| |
| public void visitAnyMember(Clazz clazz, Member member) |
| { |
| // Special cases: <clinit> and <init> are always kept unchanged. |
| // We can ignore them here. |
| String name = member.getName(clazz); |
| if (name.equals(ClassConstants.INTERNAL_METHOD_NAME_CLINIT) || |
| name.equals(ClassConstants.INTERNAL_METHOD_NAME_INIT)) |
| { |
| return; |
| } |
| |
| // Get the member's descriptor. |
| String descriptor = member.getDescriptor(clazz); |
| |
| // Check whether we're allowed to do aggressive overloading |
| if (!allowAggressiveOverloading) |
| { |
| // Trim the return argument from the descriptor if not. |
| // Works for fields and methods alike. |
| descriptor = descriptor.substring(0, descriptor.indexOf(')')+1); |
| } |
| |
| // Get the name map, creating a new one if necessary. |
| Map nameMap = retrieveNameMap(descriptorMap, descriptor); |
| |
| // Get the member's new name. |
| String newName = newMemberName(member); |
| |
| // Assign a new one, if necessary. |
| if (newName == null) |
| { |
| // Find an acceptable new name. |
| nameFactory.reset(); |
| |
| do |
| { |
| newName = nameFactory.nextName(); |
| } |
| while (nameMap.containsKey(newName)); |
| |
| // Remember not to use the new name again in this name space. |
| nameMap.put(newName, name); |
| |
| // Assign the new name. |
| setNewMemberName(member, newName); |
| } |
| } |
| |
| |
| // Small utility methods. |
| |
| /** |
| * Gets the name map, based on the given map and a given descriptor. |
| * A new empty map is created if necessary. |
| * @param descriptorMap the map of descriptors to [new name - old name] maps. |
| * @param descriptor the class member descriptor. |
| * @return the corresponding name map. |
| */ |
| static Map retrieveNameMap(Map descriptorMap, String descriptor) |
| { |
| // See if we can find the nested map with this descriptor key. |
| Map nameMap = (Map)descriptorMap.get(descriptor); |
| |
| // Create a new one if not. |
| if (nameMap == null) |
| { |
| nameMap = new HashMap(); |
| descriptorMap.put(descriptor, nameMap); |
| } |
| |
| return nameMap; |
| } |
| |
| |
| /** |
| * Assigns a fixed new name to the given class member. |
| * @param member the class member. |
| * @param name the new name. |
| */ |
| static void setFixedNewMemberName(Member member, String name) |
| { |
| VisitorAccepter lastVisitorAccepter = MethodLinker.lastVisitorAccepter(member); |
| |
| if (!(lastVisitorAccepter instanceof LibraryMember) && |
| !(lastVisitorAccepter instanceof MyFixedName)) |
| { |
| lastVisitorAccepter.setVisitorInfo(new MyFixedName(name)); |
| } |
| else |
| { |
| lastVisitorAccepter.setVisitorInfo(name); |
| } |
| } |
| |
| |
| /** |
| * Assigns a new name to the given class member. |
| * @param member the class member. |
| * @param name the new name. |
| */ |
| static void setNewMemberName(Member member, String name) |
| { |
| MethodLinker.lastVisitorAccepter(member).setVisitorInfo(name); |
| } |
| |
| |
| /** |
| * Returns whether the new name of the given class member is fixed. |
| * @param member the class member. |
| * @return whether its new name is fixed. |
| */ |
| static boolean hasFixedNewMemberName(Member member) |
| { |
| VisitorAccepter lastVisitorAccepter = MethodLinker.lastVisitorAccepter(member); |
| |
| return lastVisitorAccepter instanceof LibraryMember || |
| lastVisitorAccepter instanceof MyFixedName; |
| } |
| |
| |
| /** |
| * Retrieves the new name of the given class member. |
| * @param member the class member. |
| * @return the class member's new name, or <code>null</code> if it doesn't |
| * have one yet. |
| */ |
| static String newMemberName(Member member) |
| { |
| return (String)MethodLinker.lastVisitorAccepter(member).getVisitorInfo(); |
| } |
| |
| |
| /** |
| * This VisitorAccepter can be used to wrap a name string, to indicate that |
| * the name is fixed. |
| */ |
| private static class MyFixedName implements VisitorAccepter |
| { |
| private String newName; |
| |
| |
| public MyFixedName(String newName) |
| { |
| this.newName = newName; |
| } |
| |
| |
| // Implementations for VisitorAccepter. |
| |
| public Object getVisitorInfo() |
| { |
| return newName; |
| } |
| |
| |
| public void setVisitorInfo(Object visitorInfo) |
| { |
| newName = (String)visitorInfo; |
| } |
| } |
| } |