1 /*
2 * Copyright (c) 2023, 2024, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25 package jdk.internal.classfile.impl.verifier;
26
27 import java.lang.classfile.Annotation;
28 import java.lang.classfile.AnnotationValue;
29 import java.lang.constant.ClassDesc;
30 import static java.lang.constant.ConstantDescs.CLASS_INIT_NAME;
31 import static java.lang.constant.ConstantDescs.INIT_NAME;
32 import java.util.ArrayList;
33 import java.util.HashSet;
34 import java.util.List;
35 import java.util.function.Consumer;
36 import java.util.stream.Collectors;
37 import java.lang.classfile.Attribute;
38 import java.lang.classfile.AttributedElement;
39 import java.lang.classfile.Attributes;
40 import java.lang.classfile.ClassModel;
41 import java.lang.classfile.ClassFileElement;
42 import java.lang.classfile.CodeModel;
43 import java.lang.classfile.CompoundElement;
44 import java.lang.classfile.CustomAttribute;
45 import java.lang.classfile.FieldModel;
46 import java.lang.classfile.MethodModel;
47 import java.lang.classfile.TypeAnnotation;
48 import java.lang.classfile.TypeKind;
49 import java.lang.classfile.attribute.*;
50 import java.lang.classfile.constantpool.*;
51 import java.lang.constant.ConstantDescs;
52 import java.lang.reflect.AccessFlag;
53 import java.util.Collection;
54 import java.util.function.Function;
55 import java.util.function.ToIntFunction;
56 import jdk.internal.classfile.impl.BoundAttribute;
57 import jdk.internal.classfile.impl.Util;
58
59 /**
60 * ParserVerifier performs selected checks of the class file format according to
61 * {@jvms 4.8 Format Checking}
62 *
63 * @see <a href="https://raw.githubusercontent.com/openjdk/jdk/master/src/hotspot/share/classfile/classFileParser.cpp">hotspot/share/classfile/classFileParser.cpp</a>
64 */
65 public record ParserVerifier(ClassModel classModel) {
66
67 List<VerifyError> verify() {
68 var errors = new ArrayList<VerifyError>();
69 verifyConstantPool(errors);
70 verifyInterfaces(errors);
71 verifyFields(errors);
72 verifyMethods(errors);
73 verifyAttributes(classModel, errors);
74 return errors;
75 }
76
77 private void verifyConstantPool(List<VerifyError> errors) {
78 for (var cpe : classModel.constantPool()) {
79 Consumer<Runnable> check = c -> {
80 try {
81 c.run();
82 } catch (VerifyError|Exception e) {
83 errors.add(new VerifyError("%s at constant pool index %d in %s".formatted(e.getMessage(), cpe.index(), toString(classModel))));
84 }
85 };
86 check.accept(switch (cpe) {
87 case DoubleEntry de -> de::doubleValue;
88 case FloatEntry fe -> fe::floatValue;
89 case IntegerEntry ie -> ie::intValue;
90 case LongEntry le -> le::longValue;
91 case Utf8Entry ue -> ue::stringValue;
92 case ConstantDynamicEntry cde -> cde::asSymbol;
93 case InvokeDynamicEntry ide -> ide::asSymbol;
94 case ClassEntry ce -> ce::asSymbol;
95 case StringEntry se -> se::stringValue;
96 case MethodHandleEntry mhe -> mhe::asSymbol;
97 case MethodTypeEntry mte -> mte::asSymbol;
98 case FieldRefEntry fre -> {
99 check.accept(fre.owner()::asSymbol);
100 check.accept(fre::typeSymbol);
101 yield () -> verifyFieldName(fre.name().stringValue());
102 }
103 case InterfaceMethodRefEntry imre -> {
104 check.accept(imre.owner()::asSymbol);
105 check.accept(imre::typeSymbol);
106 yield () -> verifyMethodName(imre.name().stringValue());
107 }
108 case MethodRefEntry mre -> {
109 check.accept(mre.owner()::asSymbol);
110 check.accept(mre::typeSymbol);
111 yield () -> verifyMethodName(mre.name().stringValue());
112 }
113 case ModuleEntry me -> me::asSymbol;
114 case NameAndTypeEntry nate -> {
115 check.accept(nate.name()::stringValue);
116 yield () -> nate.type().stringValue();
117 }
118 case PackageEntry pe -> pe::asSymbol;
119 });
120 }
121 }
122
123 private void verifyFieldName(String name) {
124 if (name.length() == 0 || name.chars().anyMatch(ch -> switch(ch) {
125 case '.', ';', '[', '/' -> true;
126 default -> false;
127 })) {
128 throw new VerifyError("Illegal field name %s in %s".formatted(name, toString(classModel)));
129 }
130 }
131
132 private void verifyMethodName(String name) {
133 if (!name.equals(INIT_NAME)
134 && !name.equals(CLASS_INIT_NAME)
135 && (name.length() == 0 || name.chars().anyMatch(ch -> switch(ch) {
136 case '.', ';', '[', '/', '<', '>' -> true;
137 default -> false;
138 }))) {
139 throw new VerifyError("Illegal method name %s in %s".formatted(name, toString(classModel)));
140 }
141 }
142
143 private void verifyInterfaces(List<VerifyError> errors) {
144 var intfs = new HashSet<ClassEntry>();
145 for (var intf : classModel.interfaces()) {
146 if (!intfs.add(intf)) {
147 errors.add(new VerifyError("Duplicate interface %s in %s".formatted(intf.asSymbol().displayName(), toString(classModel))));
148 }
149 }
150 }
151
152 private void verifyFields(List<VerifyError> errors) {
153 record F(Utf8Entry name, Utf8Entry type) {};
154 var fields = new HashSet<F>();
155 for (var f : classModel.fields()) try {
156 if (!fields.add(new F(f.fieldName(), f.fieldType()))) {
157 errors.add(new VerifyError("Duplicate field name %s with signature %s in %s".formatted(f.fieldName().stringValue(), f.fieldType().stringValue(), toString(classModel))));
158 }
159 verifyFieldName(f.fieldName().stringValue());
160 } catch (VerifyError ve) {
161 errors.add(ve);
162 }
163 }
164
165 private void verifyMethods(List<VerifyError> errors) {
166 record M(Utf8Entry name, Utf8Entry type) {};
167 var methods = new HashSet<M>();
168 for (var m : classModel.methods()) try {
169 if (!methods.add(new M(m.methodName(), m.methodType()))) {
170 errors.add(new VerifyError("Duplicate method name %s with signature %s in %s".formatted(m.methodName().stringValue(), m.methodType().stringValue(), toString(classModel))));
171 }
172 if (m.methodName().equalsString(CLASS_INIT_NAME)
173 && !m.flags().has(AccessFlag.STATIC)) {
174 errors.add(new VerifyError("Method <clinit> is not static in %s".formatted(toString(classModel))));
175 }
176 if (classModel.flags().has(AccessFlag.INTERFACE)
177 && m.methodName().equalsString(INIT_NAME)) {
178 errors.add(new VerifyError("Interface cannot have a method named <init> in %s".formatted(toString(classModel))));
179 }
180 verifyMethodName(m.methodName().stringValue());
181 } catch (VerifyError ve) {
182 errors.add(ve);
183 }
184 }
185
186 private void verifyAttributes(ClassFileElement cfe, List<VerifyError> errors) {
187 if (cfe instanceof AttributedElement ae) {
188 var attrNames = new HashSet<String>();
189 for (var a : ae.attributes()) {
190 if (!a.attributeMapper().allowMultiple() && !attrNames.add(a.attributeName())) {
191 errors.add(new VerifyError("Multiple %s attributes in %s".formatted(a.attributeName(), toString(ae))));
192 }
193 verifyAttribute(ae, a, errors);
194 }
195 }
196 switch (cfe) {
197 case CompoundElement<?> comp -> {
198 for (var e : comp) verifyAttributes(e, errors);
199 }
200 case RecordAttribute ra -> {
201 for(var rc : ra.components()) verifyAttributes(rc, errors);
202 }
203 default -> {}
204 }
205 }
206
207 private void verifyAttribute(AttributedElement ae, Attribute<?> a, List<VerifyError> errors) {
208 int size = switch (a) {
209 case AnnotationDefaultAttribute aa ->
210 valueSize(aa.defaultValue());
211 case BootstrapMethodsAttribute bma ->
212 2 + bma.bootstrapMethods().stream().mapToInt(bm -> 4 + 2 * bm.arguments().size()).sum();
213 case CharacterRangeTableAttribute cra ->
214 2 + 14 * cra.characterRangeTable().size();
215 case CodeAttribute ca -> {
216 MethodModel mm = (MethodModel)ae;
217 if (mm.flags().has(AccessFlag.NATIVE) || mm.flags().has(AccessFlag.ABSTRACT)) {
218 errors.add(new VerifyError("Code attribute in native or abstract %s".formatted(toString(ae))));
219 }
220 if (ca.maxLocals() < Util.maxLocals(mm.flags().flagsMask(), mm.methodTypeSymbol())) {
221 errors.add(new VerifyError("Arguments can't fit into locals in %s".formatted(toString(ae))));
222 }
223 yield 10 + ca.codeLength() + 8 * ca.exceptionHandlers().size() + attributesSize(ca.attributes());
224 }
225 case CompilationIDAttribute cida -> {
226 cida.compilationId();
227 yield 2;
228 }
229 case ConstantValueAttribute cva -> {
230 ClassDesc type = ((FieldModel)ae).fieldTypeSymbol();
231 ConstantValueEntry cve = cva.constant();
232 if (!switch (TypeKind.from(type)) {
233 case BOOLEAN, BYTE, CHAR, INT, SHORT -> cve instanceof IntegerEntry;
234 case DOUBLE -> cve instanceof DoubleEntry;
235 case FLOAT -> cve instanceof FloatEntry;
236 case LONG -> cve instanceof LongEntry;
237 case REFERENCE -> type.equals(ConstantDescs.CD_String) && cve instanceof StringEntry;
238 case VOID -> false;
239 }) {
240 errors.add(new VerifyError("Bad constant value type in %s".formatted(toString(ae))));
241 }
242 yield 2;
243 }
244 case DeprecatedAttribute _ ->
245 0;
246 case EnclosingMethodAttribute ema -> {
247 ema.enclosingClass();
248 ema.enclosingMethod();
249 yield 4;
250 }
251 case ExceptionsAttribute ea ->
252 2 + 2 * ea.exceptions().size();
253 case InnerClassesAttribute ica -> {
254 for (var ici : ica.classes()) {
255 if (ici.outerClass().isPresent() && ici.outerClass().get().equals(ici.innerClass())) {
256 errors.add(new VerifyError("Class is both outer and inner class in %s".formatted(toString(ae))));
257 }
258 }
259 yield 2 + 8 * ica.classes().size();
260 }
261 case LineNumberTableAttribute lta ->
262 2 + 4 * lta.lineNumbers().size();
263 case LocalVariableTableAttribute lvta ->
264 2 + 10 * lvta.localVariables().size();
265 case LocalVariableTypeTableAttribute lvta ->
266 2 + 10 * lvta.localVariableTypes().size();
267 case MethodParametersAttribute mpa ->
268 1 + 4 * mpa.parameters().size();
269 case ModuleAttribute ma ->
270 16 + subSize(ma.exports(), ModuleExportInfo::exportsTo, 6, 2)
271 + subSize(ma.opens(), ModuleOpenInfo::opensTo, 6, 2)
272 + subSize(ma.provides(), ModuleProvideInfo::providesWith, 4, 2)
273 + 6 * ma.requires().size()
274 + 2 * ma.uses().size();
275 case ModuleHashesAttribute mha ->
276 2 + moduleHashesSize(mha.hashes());
277 case ModuleMainClassAttribute mmca -> {
278 mmca.mainClass();
279 yield 2;
280 }
281 case ModulePackagesAttribute mpa ->
282 2 + 2 * mpa.packages().size();
283 case ModuleResolutionAttribute mra ->
284 2;
285 case ModuleTargetAttribute mta -> {
286 mta.targetPlatform();
287 yield 2;
288 }
289 case NestHostAttribute nha -> {
290 nha.nestHost();
291 yield 2;
292 }
293 case NestMembersAttribute nma -> {
294 if (ae.findAttribute(Attributes.nestHost()).isPresent()) {
295 errors.add(new VerifyError("Conflicting NestHost and NestMembers attributes in %s".formatted(toString(ae))));
296 }
297 yield 2 + 2 * nma.nestMembers().size();
298 }
299 case PermittedSubclassesAttribute psa -> {
300 if (classModel.flags().has(AccessFlag.FINAL)) {
301 errors.add(new VerifyError("PermittedSubclasses attribute in final %s".formatted(toString(ae))));
302 }
303 yield 2 + 2 * psa.permittedSubclasses().size();
304 }
305 case RecordAttribute ra ->
306 componentsSize(ra.components());
307 case RuntimeVisibleAnnotationsAttribute aa ->
308 annotationsSize(aa.annotations());
309 case RuntimeInvisibleAnnotationsAttribute aa ->
310 annotationsSize(aa.annotations());
311 case RuntimeVisibleTypeAnnotationsAttribute aa ->
312 typeAnnotationsSize(aa.annotations());
313 case RuntimeInvisibleTypeAnnotationsAttribute aa ->
314 typeAnnotationsSize(aa.annotations());
315 case RuntimeVisibleParameterAnnotationsAttribute aa ->
316 parameterAnnotationsSize(aa.parameterAnnotations());
317 case RuntimeInvisibleParameterAnnotationsAttribute aa ->
318 parameterAnnotationsSize(aa.parameterAnnotations());
319 case SignatureAttribute sa -> {
320 sa.signature();
321 yield 2;
322 }
323 case SourceDebugExtensionAttribute sda ->
324 sda.contents().length;
325 case SourceFileAttribute sfa -> {
326 sfa.sourceFile();
327 yield 2;
328 }
329 case SourceIDAttribute sida -> {
330 sida.sourceId();
331 yield 2;
332 }
333 case StackMapTableAttribute smta ->
334 2 + subSize(smta.entries(), frame -> stackMapFrameSize(frame));
335 case SyntheticAttribute _ ->
336 0;
337 case UnknownAttribute _ ->
338 -1;
339 case CustomAttribute<?> _ ->
340 -1;
341 default -> // should not happen if all known attributes are verified
342 throw new AssertionError(a);
343 };
344 if (size >= 0 && size != ((BoundAttribute)a).payloadLen()) {
345 errors.add(new VerifyError("Wrong %s attribute length in %s".formatted(a.attributeName(), toString(ae))));
346 }
347 }
348
349 private static <T, S extends Collection<?>> int subSize(Collection<T> entries, Function<T, S> subMH, int entrySize, int subSize) {
350 return subSize(entries, (ToIntFunction<T>) t -> entrySize + subSize * subMH.apply(t).size());
351 }
352
353 private static <T> int subSize(Collection<T> entries, ToIntFunction<T> subMH) {
354 int l = 0;
355 for (T entry : entries) {
356 l += subMH.applyAsInt(entry);
357 }
358 return l;
359 }
360
361 private static int componentsSize(List<RecordComponentInfo> comps) {
362 int l = 2;
363 for (var rc : comps) {
364 l += 4 + attributesSize(rc.attributes());
365 }
366 return l;
367 }
368
369 private static int attributesSize(List<Attribute<?>> attrs) {
370 int l = 2;
371 for (var a : attrs) {
372 l += 6 + ((BoundAttribute)a).payloadLen();
373 }
374 return l;
375 }
376
377 private static int parameterAnnotationsSize(List<List<Annotation>> pans) {
378 int l = 1;
379 for (var ans : pans) {
380 l += annotationsSize(ans);
381 }
382 return l;
383 }
384
385 private static int annotationsSize(List<Annotation> ans) {
386 int l = 2;
387 for (var an : ans) {
388 l += annotationSize(an);
389 }
390 return l;
391 }
392
393 private static int typeAnnotationsSize(List<TypeAnnotation> ans) {
394 int l = 2;
395 for (var an : ans) {
396 l += 2 + an.targetInfo().size() + 2 * an.targetPath().size() + annotationSize(an.annotation());
397 }
398 return l;
399 }
400
401 private static int annotationSize(Annotation an) {
402 int l = 4;
403 for (var el : an.elements()) {
404 l += 2 + valueSize(el.value());
405 }
406 return l;
407 }
408
409 private static int valueSize(AnnotationValue val) {
410 return 1 + switch (val) {
411 case AnnotationValue.OfAnnotation oan ->
412 annotationSize(oan.annotation());
413 case AnnotationValue.OfArray oar -> {
414 int l = 2;
415 for (var v : oar.values()) {
416 l += valueSize(v);
417 }
418 yield l;
419 }
420 case AnnotationValue.OfConstant _, AnnotationValue.OfClass _ -> 2;
421 case AnnotationValue.OfEnum _ -> 4;
422 };
423 }
424
425 private static int moduleHashesSize(List<ModuleHashInfo> hashes) {
426 int l = 2;
427 for (var h : hashes) {
428 h.moduleName();
429 l += 4 + h.hash().length;
430 }
431 return l;
432 }
433
434 private int stackMapFrameSize(StackMapFrameInfo frame) {
435 int ft = frame.frameType();
436 if (ft < 64) return 1;
437 if (ft < 128) return 1 + verificationTypeSize(frame.stack().getFirst());
438 if (ft > 246) {
439 if (ft == 247) return 3 + verificationTypeSize(frame.stack().getFirst());
440 if (ft < 252) return 3;
441 if (ft < 255) {
442 var loc = frame.locals();
443 int l = 3;
444 for (int i = loc.size() + 251 - ft; i < loc.size(); i++) {
445 l += verificationTypeSize(loc.get(i));
446 }
447 return l;
448 }
449 if (ft == 255) {
450 int l = 7;
451 for (var vt : frame.stack()) {
452 l += verificationTypeSize(vt);
453 }
454 for (var vt : frame.locals()) {
455 l += verificationTypeSize(vt);
456 }
457 return l;
458 }
459 }
460 throw new IllegalArgumentException("Invalid stack map frame type " + ft);
461 }
462
463 private static int verificationTypeSize(StackMapFrameInfo.VerificationTypeInfo vti) {
464 return switch (vti) {
465 case StackMapFrameInfo.SimpleVerificationTypeInfo _ -> 1;
466 case StackMapFrameInfo.ObjectVerificationTypeInfo ovti -> {
467 ovti.classSymbol();
468 yield 3;
469 }
470 case StackMapFrameInfo.UninitializedVerificationTypeInfo _ -> 3;
471 };
472 }
473
474 private String className() {
475 return classModel.thisClass().asSymbol().displayName();
476 }
477
478 private String toString(AttributedElement ae) {
479 return switch (ae) {
480 case CodeModel m -> "Code attribute for " + toString(m.parent().get());
481 case FieldModel m -> "field %s.%s".formatted(
482 className(),
483 m.fieldName().stringValue());
484 case MethodModel m -> "method %s::%s(%s)".formatted(
485 className(),
486 m.methodName().stringValue(),
487 m.methodTypeSymbol().parameterList().stream().map(ClassDesc::displayName).collect(Collectors.joining(",")));
488 case RecordComponentInfo i -> "Record component %s of class %s".formatted(
489 i.name().stringValue(),
490 className());
491 default -> "class " + className();
492 };
493 }
494 }