1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
|
/*
* ProGuard -- shrinking, optimization, obfuscation, and preverification
* of Java bytecode.
*
* Copyright (c) 2002-2014 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 (ClassUtil.isInitializer(name))
{
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;
}
}
}
|
