1 /*
2 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
3 *
4 * This code is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License version 2 only, as
6 * published by the Free Software Foundation. Oracle designates this
7 * particular file as subject to the "Classpath" exception as provided
8 * by Oracle in the LICENSE file that accompanied this code.
9 *
10 * This code is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
13 * version 2 for more details (a copy is included in the LICENSE file that
14 * accompanied this code).
15 *
16 * You should have received a copy of the GNU General Public License version
17 * 2 along with this work; if not, write to the Free Software Foundation,
18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
19 *
20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
21 * or visit www.oracle.com if you need additional information or have any
22 * questions.
23 */
24
25 /*
26 * This file is available under and governed by the GNU General Public
27 * License version 2 only, as published by the Free Software Foundation.
28 * However, the following notice accompanied the original version of this
29 * file:
30 *
31 * ASM: a very small and fast Java bytecode manipulation framework
32 * Copyright (c) 2000-2011 INRIA, France Telecom
33 * All rights reserved.
34 *
35 * Redistribution and use in source and binary forms, with or without
36 * modification, are permitted provided that the following conditions
37 * are met:
38 * 1. Redistributions of source code must retain the above copyright
39 * notice, this list of conditions and the following disclaimer.
40 * 2. Redistributions in binary form must reproduce the above copyright
41 * notice, this list of conditions and the following disclaimer in the
42 * documentation and/or other materials provided with the distribution.
43 * 3. Neither the name of the copyright holders nor the names of its
44 * contributors may be used to endorse or promote products derived from
45 * this software without specific prior written permission.
46 *
47 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
48 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
49 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
50 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
51 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
52 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
53 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
54 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
55 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
56 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
57 * THE POSSIBILITY OF SUCH DAMAGE.
58 */
59 package jdk.internal.org.objectweb.asm.commons;
60
61 import java.io.ByteArrayOutputStream;
62 import java.io.DataOutput;
63 import java.io.DataOutputStream;
64 import java.io.IOException;
65 import java.security.MessageDigest;
66 import java.util.ArrayList;
67 import java.util.Arrays;
68 import java.util.Collection;
69
70 import jdk.internal.org.objectweb.asm.ClassVisitor;
71 import jdk.internal.org.objectweb.asm.FieldVisitor;
72 import jdk.internal.org.objectweb.asm.MethodVisitor;
73 import jdk.internal.org.objectweb.asm.Opcodes;
74
75 /**
76 * A {@link ClassVisitor} that adds a serial version unique identifier to a
77 * class if missing. Here is typical usage of this class:
78 *
79 * <pre>
80 * ClassWriter cw = new ClassWriter(...);
81 * ClassVisitor sv = new SerialVersionUIDAdder(cw);
82 * ClassVisitor ca = new MyClassAdapter(sv);
83 * new ClassReader(orginalClass).accept(ca, false);
84 * </pre>
85 *
86 * The SVUID algorithm can be found <a href=
87 * "http://java.sun.com/j2se/1.4.2/docs/guide/serialization/spec/class.html"
88 * >http://java.sun.com/j2se/1.4.2/docs/guide/serialization/spec/class.html</a>:
89 *
90 * <pre>
91 * The serialVersionUID is computed using the signature of a stream of bytes
92 * that reflect the class definition. The National Institute of Standards and
93 * Technology (NIST) Secure Hash Algorithm (SHA-1) is used to compute a
94 * signature for the stream. The first two 32-bit quantities are used to form a
95 * 64-bit hash. A java.lang.DataOutputStream is used to convert primitive data
96 * types to a sequence of bytes. The values input to the stream are defined by
97 * the Java Virtual Machine (VM) specification for classes.
98 *
99 * The sequence of items in the stream is as follows:
100 *
101 * 1. The class name written using UTF encoding.
102 * 2. The class modifiers written as a 32-bit integer.
103 * 3. The name of each interface sorted by name written using UTF encoding.
104 * 4. For each field of the class sorted by field name (except private static
105 * and private transient fields):
106 * 1. The name of the field in UTF encoding.
107 * 2. The modifiers of the field written as a 32-bit integer.
108 * 3. The descriptor of the field in UTF encoding
109 * 5. If a class initializer exists, write out the following:
110 * 1. The name of the method, <clinit>, in UTF encoding.
111 * 2. The modifier of the method, java.lang.reflect.Modifier.STATIC,
112 * written as a 32-bit integer.
113 * 3. The descriptor of the method, ()V, in UTF encoding.
114 * 6. For each non-private constructor sorted by method name and signature:
115 * 1. The name of the method, <init>, in UTF encoding.
116 * 2. The modifiers of the method written as a 32-bit integer.
117 * 3. The descriptor of the method in UTF encoding.
118 * 7. For each non-private method sorted by method name and signature:
119 * 1. The name of the method in UTF encoding.
120 * 2. The modifiers of the method written as a 32-bit integer.
121 * 3. The descriptor of the method in UTF encoding.
122 * 8. The SHA-1 algorithm is executed on the stream of bytes produced by
123 * DataOutputStream and produces five 32-bit values sha[0..4].
124 *
125 * 9. The hash value is assembled from the first and second 32-bit values of
126 * the SHA-1 message digest. If the result of the message digest, the five
127 * 32-bit words H0 H1 H2 H3 H4, is in an array of five int values named
128 * sha, the hash value would be computed as follows:
129 *
130 * long hash = ((sha[0] >>> 24) & 0xFF) |
131 * ((sha[0] >>> 16) & 0xFF) << 8 |
132 * ((sha[0] >>> 8) & 0xFF) << 16 |
133 * ((sha[0] >>> 0) & 0xFF) << 24 |
134 * ((sha[1] >>> 24) & 0xFF) << 32 |
135 * ((sha[1] >>> 16) & 0xFF) << 40 |
136 * ((sha[1] >>> 8) & 0xFF) << 48 |
137 * ((sha[1] >>> 0) & 0xFF) << 56;
138 * </pre>
139 *
140 * @author Rajendra Inamdar, Vishal Vishnoi
141 */
142 public class SerialVersionUIDAdder extends ClassVisitor {
143
144 /**
145 * Flag that indicates if we need to compute SVUID.
146 */
147 private boolean computeSVUID;
148
149 /**
150 * Set to true if the class already has SVUID.
151 */
152 private boolean hasSVUID;
153
154 /**
155 * Classes access flags.
156 */
157 private int access;
158
159 /**
160 * Internal name of the class
161 */
162 private String name;
163
164 /**
165 * Interfaces implemented by the class.
166 */
167 private String[] interfaces;
168
169 /**
170 * Collection of fields. (except private static and private transient
171 * fields)
172 */
173 private Collection<Item> svuidFields;
174
175 /**
176 * Set to true if the class has static initializer.
177 */
178 private boolean hasStaticInitializer;
179
180 /**
181 * Collection of non-private constructors.
182 */
183 private Collection<Item> svuidConstructors;
184
185 /**
186 * Collection of non-private methods.
187 */
188 private Collection<Item> svuidMethods;
189
190 /**
191 * Creates a new {@link SerialVersionUIDAdder}. <i>Subclasses must not use
192 * this constructor</i>. Instead, they must use the
193 * {@link #SerialVersionUIDAdder(int, ClassVisitor)} version.
194 *
195 * @param cv
196 * a {@link ClassVisitor} to which this visitor will delegate
197 * calls.
198 */
199 public SerialVersionUIDAdder(final ClassVisitor cv) {
200 this(Opcodes.ASM5, cv);
201 }
202
203 /**
204 * Creates a new {@link SerialVersionUIDAdder}.
205 *
206 * @param api
207 * the ASM API version implemented by this visitor. Must be one
208 * of {@link Opcodes#ASM4} or {@link Opcodes#ASM5}.
209 * @param cv
210 * a {@link ClassVisitor} to which this visitor will delegate
211 * calls.
212 */
213 protected SerialVersionUIDAdder(final int api, final ClassVisitor cv) {
214 super(api, cv);
215 svuidFields = new ArrayList<Item>();
216 svuidConstructors = new ArrayList<Item>();
217 svuidMethods = new ArrayList<Item>();
218 }
219
220 // ------------------------------------------------------------------------
221 // Overriden methods
222 // ------------------------------------------------------------------------
223
224 /*
225 * Visit class header and get class name, access , and interfaces
226 * information (step 1,2, and 3) for SVUID computation.
227 */
228 @Override
229 public void visit(final int version, final int access, final String name,
230 final String signature, final String superName,
231 final String[] interfaces) {
232 computeSVUID = (access & Opcodes.ACC_INTERFACE) == 0;
233
234 if (computeSVUID) {
235 this.name = name;
236 this.access = access;
237 this.interfaces = interfaces;
238 }
239
240 super.visit(version, access, name, signature, superName, interfaces);
241 }
242
243 /*
244 * Visit the methods and get constructor and method information (step 5 and
245 * 7). Also determine if there is a class initializer (step 6).
246 */
247 @Override
248 public MethodVisitor visitMethod(final int access, final String name,
249 final String desc, final String signature, final String[] exceptions) {
250 if (computeSVUID) {
251 if ("<clinit>".equals(name)) {
252 hasStaticInitializer = true;
253 }
254 /*
255 * Remembers non private constructors and methods for SVUID
256 * computation For constructor and method modifiers, only the
257 * ACC_PUBLIC, ACC_PRIVATE, ACC_PROTECTED, ACC_STATIC, ACC_FINAL,
258 * ACC_SYNCHRONIZED, ACC_NATIVE, ACC_ABSTRACT and ACC_STRICT flags
259 * are used.
260 */
261 int mods = access
262 & (Opcodes.ACC_PUBLIC | Opcodes.ACC_PRIVATE
263 | Opcodes.ACC_PROTECTED | Opcodes.ACC_STATIC
264 | Opcodes.ACC_FINAL | Opcodes.ACC_SYNCHRONIZED
265 | Opcodes.ACC_NATIVE | Opcodes.ACC_ABSTRACT | Opcodes.ACC_STRICT);
266
267 // all non private methods
268 if ((access & Opcodes.ACC_PRIVATE) == 0) {
269 if ("<init>".equals(name)) {
270 svuidConstructors.add(new Item(name, mods, desc));
271 } else if (!"<clinit>".equals(name)) {
272 svuidMethods.add(new Item(name, mods, desc));
273 }
274 }
275 }
276
277 return super.visitMethod(access, name, desc, signature, exceptions);
278 }
279
280 /*
281 * Gets class field information for step 4 of the algorithm. Also determines
282 * if the class already has a SVUID.
283 */
284 @Override
285 public FieldVisitor visitField(final int access, final String name,
286 final String desc, final String signature, final Object value) {
287 if (computeSVUID) {
288 if ("serialVersionUID".equals(name)) {
289 // since the class already has SVUID, we won't be computing it.
290 computeSVUID = false;
291 hasSVUID = true;
292 }
293 /*
294 * Remember field for SVUID computation For field modifiers, only
295 * the ACC_PUBLIC, ACC_PRIVATE, ACC_PROTECTED, ACC_STATIC,
296 * ACC_FINAL, ACC_VOLATILE, and ACC_TRANSIENT flags are used when
297 * computing serialVersionUID values.
298 */
299 if ((access & Opcodes.ACC_PRIVATE) == 0
300 || (access & (Opcodes.ACC_STATIC | Opcodes.ACC_TRANSIENT)) == 0) {
301 int mods = access
302 & (Opcodes.ACC_PUBLIC | Opcodes.ACC_PRIVATE
303 | Opcodes.ACC_PROTECTED | Opcodes.ACC_STATIC
304 | Opcodes.ACC_FINAL | Opcodes.ACC_VOLATILE | Opcodes.ACC_TRANSIENT);
305 svuidFields.add(new Item(name, mods, desc));
306 }
307 }
308
309 return super.visitField(access, name, desc, signature, value);
310 }
311
312 /**
313 * Handle a bizarre special case. Nested classes (static classes declared
314 * inside another class) that are protected have their access bit set to
315 * public in their class files to deal with some odd reflection situation.
316 * Our SVUID computation must do as the JVM does and ignore access bits in
317 * the class file in favor of the access bits InnerClass attribute.
318 */
319 @Override
320 public void visitInnerClass(final String aname, final String outerName,
321 final String innerName, final int attr_access) {
322 if ((name != null) && name.equals(aname)) {
323 this.access = attr_access;
324 }
325 super.visitInnerClass(aname, outerName, innerName, attr_access);
326 }
327
328 /*
329 * Add the SVUID if class doesn't have one
330 */
331 @Override
332 public void visitEnd() {
333 // compute SVUID and add it to the class
334 if (computeSVUID && !hasSVUID) {
335 try {
336 addSVUID(computeSVUID());
337 } catch (Throwable e) {
338 throw new RuntimeException("Error while computing SVUID for "
339 + name, e);
340 }
341 }
342
343 super.visitEnd();
344 }
345
346 // ------------------------------------------------------------------------
347 // Utility methods
348 // ------------------------------------------------------------------------
349
350 /**
351 * Returns true if the class already has a SVUID field. The result of this
352 * method is only valid when visitEnd is or has been called.
353 *
354 * @return true if the class already has a SVUID field.
355 */
356 public boolean hasSVUID() {
357 return hasSVUID;
358 }
359
360 protected void addSVUID(long svuid) {
361 FieldVisitor fv = super.visitField(Opcodes.ACC_FINAL
362 + Opcodes.ACC_STATIC, "serialVersionUID", "J", null, new Long(
363 svuid));
364 if (fv != null) {
365 fv.visitEnd();
366 }
367 }
368
369 /**
370 * Computes and returns the value of SVUID.
371 *
372 * @return Returns the serial version UID
373 * @throws IOException
374 * if an I/O error occurs
375 */
376 protected long computeSVUID() throws IOException {
377 ByteArrayOutputStream bos;
378 DataOutputStream dos = null;
379 long svuid = 0;
380
381 try {
382 bos = new ByteArrayOutputStream();
383 dos = new DataOutputStream(bos);
384
385 /*
386 * 1. The class name written using UTF encoding.
387 */
388 dos.writeUTF(name.replace('/', '.'));
389
390 /*
391 * 2. The class modifiers written as a 32-bit integer.
392 */
393 dos.writeInt(access
394 & (Opcodes.ACC_PUBLIC | Opcodes.ACC_FINAL
395 | Opcodes.ACC_INTERFACE | Opcodes.ACC_ABSTRACT));
396
397 /*
398 * 3. The name of each interface sorted by name written using UTF
399 * encoding.
400 */
401 Arrays.sort(interfaces);
402 for (int i = 0; i < interfaces.length; i++) {
403 dos.writeUTF(interfaces[i].replace('/', '.'));
404 }
405
406 /*
407 * 4. For each field of the class sorted by field name (except
408 * private static and private transient fields):
409 *
410 * 1. The name of the field in UTF encoding. 2. The modifiers of the
411 * field written as a 32-bit integer. 3. The descriptor of the field
412 * in UTF encoding
413 *
414 * Note that field signatures are not dot separated. Method and
415 * constructor signatures are dot separated. Go figure...
416 */
417 writeItems(svuidFields, dos, false);
418
419 /*
420 * 5. If a class initializer exists, write out the following: 1. The
421 * name of the method, <clinit>, in UTF encoding. 2. The modifier of
422 * the method, java.lang.reflect.Modifier.STATIC, written as a
423 * 32-bit integer. 3. The descriptor of the method, ()V, in UTF
424 * encoding.
425 */
426 if (hasStaticInitializer) {
427 dos.writeUTF("<clinit>");
428 dos.writeInt(Opcodes.ACC_STATIC);
429 dos.writeUTF("()V");
430 } // if..
431
432 /*
433 * 6. For each non-private constructor sorted by method name and
434 * signature: 1. The name of the method, <init>, in UTF encoding. 2.
435 * The modifiers of the method written as a 32-bit integer. 3. The
436 * descriptor of the method in UTF encoding.
437 */
438 writeItems(svuidConstructors, dos, true);
439
440 /*
441 * 7. For each non-private method sorted by method name and
442 * signature: 1. The name of the method in UTF encoding. 2. The
443 * modifiers of the method written as a 32-bit integer. 3. The
444 * descriptor of the method in UTF encoding.
445 */
446 writeItems(svuidMethods, dos, true);
447
448 dos.flush();
449
450 /*
451 * 8. The SHA-1 algorithm is executed on the stream of bytes
452 * produced by DataOutputStream and produces five 32-bit values
453 * sha[0..4].
454 */
455 byte[] hashBytes = computeSHAdigest(bos.toByteArray());
456
457 /*
458 * 9. The hash value is assembled from the first and second 32-bit
459 * values of the SHA-1 message digest. If the result of the message
460 * digest, the five 32-bit words H0 H1 H2 H3 H4, is in an array of
461 * five int values named sha, the hash value would be computed as
462 * follows:
463 *
464 * long hash = ((sha[0] >>> 24) & 0xFF) | ((sha[0] >>> 16) & 0xFF)
465 * << 8 | ((sha[0] >>> 8) & 0xFF) << 16 | ((sha[0] >>> 0) & 0xFF) <<
466 * 24 | ((sha[1] >>> 24) & 0xFF) << 32 | ((sha[1] >>> 16) & 0xFF) <<
467 * 40 | ((sha[1] >>> 8) & 0xFF) << 48 | ((sha[1] >>> 0) & 0xFF) <<
468 * 56;
469 */
470 for (int i = Math.min(hashBytes.length, 8) - 1; i >= 0; i--) {
471 svuid = (svuid << 8) | (hashBytes[i] & 0xFF);
472 }
473 } finally {
474 // close the stream (if open)
475 if (dos != null) {
476 dos.close();
477 }
478 }
479
480 return svuid;
481 }
482
483 /**
484 * Returns the SHA-1 message digest of the given value.
485 *
486 * @param value
487 * the value whose SHA message digest must be computed.
488 * @return the SHA-1 message digest of the given value.
489 */
490 protected byte[] computeSHAdigest(final byte[] value) {
491 try {
492 return MessageDigest.getInstance("SHA").digest(value);
493 } catch (Exception e) {
494 throw new UnsupportedOperationException(e.toString());
495 }
496 }
497
498 /**
499 * Sorts the items in the collection and writes it to the data output stream
500 *
501 * @param itemCollection
502 * collection of items
503 * @param dos
504 * a <code>DataOutputStream</code> value
505 * @param dotted
506 * a <code>boolean</code> value
507 * @exception IOException
508 * if an error occurs
509 */
510 private static void writeItems(final Collection<Item> itemCollection,
511 final DataOutput dos, final boolean dotted) throws IOException {
512 int size = itemCollection.size();
513 Item[] items = itemCollection.toArray(new Item[size]);
514 Arrays.sort(items);
515 for (int i = 0; i < size; i++) {
516 dos.writeUTF(items[i].name);
517 dos.writeInt(items[i].access);
518 dos.writeUTF(dotted ? items[i].desc.replace('/', '.')
519 : items[i].desc);
520 }
521 }
522
523 // ------------------------------------------------------------------------
524 // Inner classes
525 // ------------------------------------------------------------------------
526
527 private static class Item implements Comparable<Item> {
528
529 final String name;
530
531 final int access;
532
533 final String desc;
534
535 Item(final String name, final int access, final String desc) {
536 this.name = name;
537 this.access = access;
538 this.desc = desc;
539 }
540
541 public int compareTo(final Item other) {
542 int retVal = name.compareTo(other.name);
543 if (retVal == 0) {
544 retVal = desc.compareTo(other.desc);
545 }
546 return retVal;
547 }
548
549 @Override
550 public boolean equals(final Object o) {
551 if (o instanceof Item) {
552 return compareTo((Item) o) == 0;
553 }
554 return false;
555 }
556
557 @Override
558 public int hashCode() {
559 return (name + desc).hashCode();
560 }
561 }
562 }