1 /*
2 * Copyright (C) 2018, The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #include "aidl.h"
18
19 #include <map>
20 #include <string>
21 #include <vector>
22
23 #include <android-base/result.h>
24 #include <android-base/strings.h>
25 #include <gtest/gtest.h>
26
27 #include "aidl_dumpapi.h"
28 #include "aidl_language.h"
29 #include "import_resolver.h"
30 #include "logging.h"
31 #include "options.h"
32
33 namespace android {
34 namespace aidl {
35
36 using android::base::Error;
37 using android::base::Result;
38 using android::base::StartsWith;
39 using std::map;
40 using std::set;
41 using std::string;
42 using std::vector;
43
Dump(const AidlDefinedType & type)44 static std::string Dump(const AidlDefinedType& type) {
45 string code;
46 CodeWriterPtr out = CodeWriter::ForString(&code);
47 DumpVisitor visitor(*out);
48 type.DispatchVisit(visitor);
49 out->Close();
50 return code;
51 }
52
53 // Uses each type's Dump() and GTest utility(EqHelper).
CheckEquality(const AidlDefinedType & older,const AidlDefinedType & newer)54 static bool CheckEquality(const AidlDefinedType& older, const AidlDefinedType& newer) {
55 using testing::internal::EqHelper;
56 auto older_file = older.GetLocation().GetFile();
57 auto newer_file = newer.GetLocation().GetFile();
58 auto result = EqHelper::Compare(older_file.data(), newer_file.data(), Dump(older), Dump(newer));
59 if (!result) {
60 AIDL_ERROR(newer) << result.failure_message();
61 }
62 return result;
63 }
64
get_strict_annotations(const AidlAnnotatable & node)65 static vector<string> get_strict_annotations(const AidlAnnotatable& node) {
66 // This must be symmetrical (if you can add something, you must be able to
67 // remove it). The reason is that we have no way of knowing which interface a
68 // server serves and which interface a client serves (e.g. a callback
69 // interface). Note that this is being overly lenient. It makes sense for
70 // newer code to start accepting nullable things. However, here, we don't know
71 // if the client of an interface or the server of an interface is newer.
72 //
73 // Here are two examples to demonstrate this:
74 // - a new implementation might change so that it no longer returns null
75 // values (remove @nullable)
76 // - a new implementation might start accepting null values (add @nullable)
77 static const set<AidlAnnotation::Type> kIgnoreAnnotations{
78 AidlAnnotation::Type::NULLABLE,
79 // @JavaDerive doesn't affect read/write
80 AidlAnnotation::Type::JAVA_DERIVE,
81 AidlAnnotation::Type::JAVA_DEFAULT,
82 AidlAnnotation::Type::JAVA_DELEGATOR,
83 AidlAnnotation::Type::JAVA_ONLY_IMMUTABLE,
84 AidlAnnotation::Type::JAVA_SUPPRESS_LINT,
85 // @Backing for a enum type is checked by the enum checker
86 AidlAnnotation::Type::BACKING,
87 // @RustDerive doesn't affect read/write
88 AidlAnnotation::Type::RUST_DERIVE,
89 AidlAnnotation::Type::SUPPRESS_WARNINGS,
90 };
91 vector<string> annotations;
92 for (const auto& annotation : node.GetAnnotations()) {
93 if (kIgnoreAnnotations.find(annotation->GetType()) != kIgnoreAnnotations.end()) {
94 continue;
95 }
96 auto annotation_string = annotation->ToString();
97 // adding @Deprecated (with optional args) is okay
98 if (StartsWith(annotation_string, "@JavaPassthrough(annotation=\"@Deprecated")) {
99 continue;
100 }
101 annotations.push_back(annotation_string);
102 }
103 return annotations;
104 }
105
have_compatible_annotations(const AidlAnnotatable & older,const AidlAnnotatable & newer)106 static bool have_compatible_annotations(const AidlAnnotatable& older,
107 const AidlAnnotatable& newer) {
108 vector<string> olderAnnotations = get_strict_annotations(older);
109 vector<string> newerAnnotations = get_strict_annotations(newer);
110 sort(olderAnnotations.begin(), olderAnnotations.end());
111 sort(newerAnnotations.begin(), newerAnnotations.end());
112 if (olderAnnotations != newerAnnotations) {
113 const string from = older.ToString().empty() ? "(empty)" : older.ToString();
114 const string to = newer.ToString().empty() ? "(empty)" : newer.ToString();
115 AIDL_ERROR(newer) << "Changed annotations: " << from << " to " << to;
116 return false;
117 }
118 return true;
119 }
120
are_compatible_types(const AidlTypeSpecifier & older,const AidlTypeSpecifier & newer)121 static bool are_compatible_types(const AidlTypeSpecifier& older, const AidlTypeSpecifier& newer) {
122 bool compatible = true;
123 if (older.Signature() != newer.Signature()) {
124 AIDL_ERROR(newer) << "Type changed: " << older.Signature() << " to " << newer.Signature()
125 << ".";
126 compatible = false;
127 }
128 compatible &= have_compatible_annotations(older, newer);
129 return compatible;
130 }
131
are_compatible_constants(const AidlDefinedType & older,const AidlDefinedType & newer)132 static bool are_compatible_constants(const AidlDefinedType& older, const AidlDefinedType& newer) {
133 bool compatible = true;
134
135 map<string, AidlConstantDeclaration*> new_constdecls;
136 for (const auto& c : newer.GetConstantDeclarations()) {
137 new_constdecls[c->GetName()] = &*c;
138 }
139
140 for (const auto& old_c : older.GetConstantDeclarations()) {
141 const auto found = new_constdecls.find(old_c->GetName());
142 if (found == new_constdecls.end()) {
143 AIDL_ERROR(old_c) << "Removed constant declaration: " << older.GetCanonicalName() << "."
144 << old_c->GetName();
145 compatible = false;
146 continue;
147 }
148
149 const auto new_c = found->second;
150 compatible &= are_compatible_types(old_c->GetType(), new_c->GetType());
151
152 const string old_value = old_c->ValueString(AidlConstantValueDecorator);
153 const string new_value = new_c->ValueString(AidlConstantValueDecorator);
154 if (old_value != new_value) {
155 AIDL_ERROR(newer) << "Changed constant value: " << older.GetCanonicalName() << "."
156 << old_c->GetName() << " from " << old_value << " to " << new_value << ".";
157 compatible = false;
158 }
159 }
160 return compatible;
161 }
162
are_compatible_interfaces(const AidlInterface & older,const AidlInterface & newer)163 static bool are_compatible_interfaces(const AidlInterface& older, const AidlInterface& newer) {
164 bool compatible = true;
165
166 map<string, AidlMethod*> new_methods;
167 for (const auto& m : newer.AsInterface()->GetMethods()) {
168 new_methods.emplace(m->Signature(), m.get());
169 }
170
171 for (const auto& old_m : older.AsInterface()->GetMethods()) {
172 const auto found = new_methods.find(old_m->Signature());
173 if (found == new_methods.end()) {
174 AIDL_ERROR(old_m) << "Removed or changed method: " << older.GetCanonicalName() << "."
175 << old_m->Signature();
176 compatible = false;
177 continue;
178 }
179
180 // Compare IDs to detect method reordering. IDs are assigned by their
181 // textual order, so if there is an ID mismatch, that means reordering
182 // has happened.
183 const auto new_m = found->second;
184
185 if (old_m->IsOneway() != new_m->IsOneway()) {
186 AIDL_ERROR(new_m) << "Oneway attribute " << (old_m->IsOneway() ? "removed" : "added") << ": "
187 << older.GetCanonicalName() << "." << old_m->Signature();
188 compatible = false;
189 }
190
191 if (old_m->GetId() != new_m->GetId()) {
192 AIDL_ERROR(new_m) << "Transaction ID changed: " << older.GetCanonicalName() << "."
193 << old_m->Signature() << " is changed from " << old_m->GetId() << " to "
194 << new_m->GetId() << ".";
195 compatible = false;
196 }
197
198 compatible &= are_compatible_types(old_m->GetType(), new_m->GetType());
199
200 const auto& old_args = old_m->GetArguments();
201 const auto& new_args = new_m->GetArguments();
202 // this is guaranteed because arguments are part of AidlMethod::Signature()
203 AIDL_FATAL_IF(old_args.size() != new_args.size(), old_m);
204 for (size_t i = 0; i < old_args.size(); i++) {
205 const AidlArgument& old_a = *(old_args.at(i));
206 const AidlArgument& new_a = *(new_args.at(i));
207 compatible &= are_compatible_types(old_a.GetType(), new_a.GetType());
208
209 if (old_a.GetDirection() != new_a.GetDirection()) {
210 AIDL_ERROR(new_m) << "Direction changed: " << old_a.GetDirectionSpecifier() << " to "
211 << new_a.GetDirectionSpecifier() << ".";
212 compatible = false;
213 }
214 }
215 }
216
217 compatible = are_compatible_constants(older, newer) && compatible;
218
219 return compatible;
220 }
221
HasZeroEnumerator(const AidlEnumDeclaration & enum_decl)222 static bool HasZeroEnumerator(const AidlEnumDeclaration& enum_decl) {
223 return std::any_of(enum_decl.GetEnumerators().begin(), enum_decl.GetEnumerators().end(),
224 [&](const unique_ptr<AidlEnumerator>& enumerator) {
225 return enumerator->GetValue()->ValueString(
226 enum_decl.GetBackingType(), AidlConstantValueDecorator) == "0";
227 });
228 }
229
EvaluatesToZero(const AidlEnumDeclaration & enum_decl,const AidlConstantValue * value)230 static bool EvaluatesToZero(const AidlEnumDeclaration& enum_decl, const AidlConstantValue* value) {
231 if (value == nullptr) return true;
232 return value->ValueString(enum_decl.GetBackingType(), AidlConstantValueDecorator) == "0";
233 }
234
are_compatible_parcelables(const AidlDefinedType & older,const AidlTypenames &,const AidlDefinedType & newer,const AidlTypenames & new_types)235 static bool are_compatible_parcelables(const AidlDefinedType& older, const AidlTypenames&,
236 const AidlDefinedType& newer,
237 const AidlTypenames& new_types) {
238 const auto& old_fields = older.GetFields();
239 const auto& new_fields = newer.GetFields();
240 if (old_fields.size() > new_fields.size()) {
241 // you can add new fields only at the end
242 AIDL_ERROR(newer) << "Number of fields in " << older.GetCanonicalName() << " is reduced from "
243 << old_fields.size() << " to " << new_fields.size() << ".";
244 return false;
245 }
246 if (newer.IsFixedSize() && old_fields.size() != new_fields.size()) {
247 AIDL_ERROR(newer) << "Number of fields in " << older.GetCanonicalName() << " is changed from "
248 << old_fields.size() << " to " << new_fields.size()
249 << ". This is an incompatible change for FixedSize types.";
250 return false;
251 }
252
253 // android.net.UidRangeParcel should be frozen to prevent breakage in legacy (b/186720556)
254 if (older.GetCanonicalName() == "android.net.UidRangeParcel" &&
255 old_fields.size() != new_fields.size()) {
256 AIDL_ERROR(newer) << "Number of fields in " << older.GetCanonicalName() << " is changed from "
257 << old_fields.size() << " to " << new_fields.size()
258 << ". But it is forbidden because of legacy support.";
259 return false;
260 }
261
262 bool compatible = true;
263 for (size_t i = 0; i < old_fields.size(); i++) {
264 const auto& old_field = old_fields.at(i);
265 const auto& new_field = new_fields.at(i);
266 compatible &= are_compatible_types(old_field->GetType(), new_field->GetType());
267
268 const string old_value = old_field->ValueString(AidlConstantValueDecorator);
269 const string new_value = new_field->ValueString(AidlConstantValueDecorator);
270 if (old_value == new_value) {
271 continue;
272 }
273 // For enum type fields, we accept setting explicit default value which is "zero"
274 auto enum_decl = new_types.GetEnumDeclaration(new_field->GetType());
275 if (old_value == "" && enum_decl && EvaluatesToZero(*enum_decl, new_field->GetDefaultValue())) {
276 continue;
277 }
278
279 AIDL_ERROR(new_field) << "Changed default value: " << old_value << " to " << new_value << ".";
280 compatible = false;
281 }
282
283 // Reordering of fields is an incompatible change.
284 for (size_t i = 0; i < new_fields.size(); i++) {
285 const auto& new_field = new_fields.at(i);
286 auto found = std::find_if(old_fields.begin(), old_fields.end(), [&new_field](const auto& f) {
287 return new_field->GetName() == f->GetName();
288 });
289 if (found != old_fields.end()) {
290 size_t old_index = std::distance(old_fields.begin(), found);
291 if (old_index != i) {
292 AIDL_ERROR(new_field) << "Reordered " << new_field->GetName() << " from " << old_index
293 << " to " << i << ".";
294 compatible = false;
295 }
296 }
297 }
298
299 for (size_t i = old_fields.size(); i < new_fields.size(); i++) {
300 const auto& new_field = new_fields.at(i);
301 if (new_field->HasUsefulDefaultValue()) {
302 continue;
303 }
304
305 // enum can't be nullable, but it's okay if it has 0 as a valid enumerator.
306 if (const auto& enum_decl = new_types.GetEnumDeclaration(new_field->GetType());
307 enum_decl != nullptr) {
308 if (HasZeroEnumerator(*enum_decl)) {
309 continue;
310 }
311
312 // TODO(b/142893595): Rephrase the message: "provide a default value or make sure ..."
313 AIDL_ERROR(new_field) << "Field '" << new_field->GetName() << "' of enum '"
314 << enum_decl->GetName()
315 << "' can't be initialized as '0'. Please make sure '"
316 << enum_decl->GetName() << "' has '0' as a valid value.";
317 compatible = false;
318 continue;
319 }
320
321 // Old API versions may suffer from the issue presented here. There is
322 // only a finite number in Android, which we must allow indefinitely.
323 struct HistoricalException {
324 std::string canonical;
325 std::string field;
326 };
327 static std::vector<HistoricalException> exceptions = {
328 {"android.net.DhcpResultsParcelable", "serverHostName"},
329 {"android.net.ResolverParamsParcel", "resolverOptions"},
330 };
331 bool excepted = false;
332 for (const HistoricalException& exception : exceptions) {
333 if (older.GetCanonicalName() == exception.canonical &&
334 new_field->GetName() == exception.field) {
335 excepted = true;
336 break;
337 }
338 }
339 if (excepted) continue;
340
341 AIDL_ERROR(new_field)
342 << "Field '" << new_field->GetName()
343 << "' does not have a useful default in some backends. Please either provide a default "
344 "value for this field or mark the field as @nullable. This value or a null value will "
345 "be used automatically when an old version of this parcelable is sent to a process "
346 "which understands a new version of this parcelable. In order to make sure your code "
347 "continues to be backwards compatible, make sure the default or null value does not "
348 "cause a semantic change to this parcelable.";
349 compatible = false;
350 }
351
352 compatible = are_compatible_constants(older, newer) && compatible;
353
354 return compatible;
355 }
356
are_compatible_enums(const AidlEnumDeclaration & older,const AidlEnumDeclaration & newer)357 static bool are_compatible_enums(const AidlEnumDeclaration& older,
358 const AidlEnumDeclaration& newer) {
359 if (!are_compatible_types(older.GetBackingType(), newer.GetBackingType())) {
360 AIDL_ERROR(newer) << "Changed backing types.";
361 return false;
362 }
363
364 std::map<std::string, const AidlConstantValue*> old_enum_map;
365 for (const auto& enumerator : older.GetEnumerators()) {
366 old_enum_map[enumerator->GetName()] = enumerator->GetValue();
367 }
368 std::map<std::string, const AidlConstantValue*> new_enum_map;
369 for (const auto& enumerator : newer.GetEnumerators()) {
370 new_enum_map[enumerator->GetName()] = enumerator->GetValue();
371 }
372
373 bool compatible = true;
374 for (const auto& [name, value] : old_enum_map) {
375 if (new_enum_map.find(name) == new_enum_map.end()) {
376 AIDL_ERROR(newer) << "Removed enumerator from " << older.GetCanonicalName() << ": " << name;
377 compatible = false;
378 continue;
379 }
380 const string old_value =
381 old_enum_map[name]->ValueString(older.GetBackingType(), AidlConstantValueDecorator);
382 const string new_value =
383 new_enum_map[name]->ValueString(newer.GetBackingType(), AidlConstantValueDecorator);
384 if (old_value != new_value) {
385 AIDL_ERROR(newer) << "Changed enumerator value: " << older.GetCanonicalName() << "::" << name
386 << " from " << old_value << " to " << new_value << ".";
387 compatible = false;
388 }
389 }
390 return compatible;
391 }
392
LoadApiDump(const Options & options,const IoDelegate & io_delegate,const std::string & dir)393 static Result<AidlTypenames> LoadApiDump(const Options& options, const IoDelegate& io_delegate,
394 const std::string& dir) {
395 Result<std::vector<std::string>> dir_files = io_delegate.ListFiles(dir);
396 if (!dir_files.ok()) {
397 AIDL_ERROR(dir) << dir_files.error();
398 return Error();
399 }
400
401 AidlTypenames typenames;
402 for (const auto& file : *dir_files) {
403 if (!android::base::EndsWith(file, ".aidl")) continue;
404 // current "dir" is added to "imports" so that referenced.aidl files in the current
405 // module are available when resolving references.
406 if (internals::load_and_validate_aidl(file, options.PlusImportDir(dir), io_delegate, &typenames,
407 nullptr /* imported_files */) != AidlError::OK) {
408 AIDL_ERROR(file) << "Failed to read.";
409 return Error();
410 }
411 }
412
413 return typenames;
414 }
415
check_api(const Options & options,const IoDelegate & io_delegate)416 bool check_api(const Options& options, const IoDelegate& io_delegate) {
417 AIDL_FATAL_IF(!options.IsStructured(), AIDL_LOCATION_HERE);
418 AIDL_FATAL_IF(options.InputFiles().size() != 2, AIDL_LOCATION_HERE)
419 << "--checkapi requires two inputs "
420 << "but got " << options.InputFiles().size();
421 auto old_tns = LoadApiDump(options, io_delegate, options.InputFiles().at(0));
422 if (!old_tns.ok()) {
423 return false;
424 }
425 auto new_tns = LoadApiDump(options, io_delegate, options.InputFiles().at(1));
426 if (!new_tns.ok()) {
427 return false;
428 }
429
430 const Options::CheckApiLevel level = options.GetCheckApiLevel();
431
432 // We don't check impoted types.
433 auto get_types_in = [](const AidlTypenames& tns, const std::string& location) {
434 std::vector<const AidlDefinedType*> types;
435 for (const auto& type : tns.AllDefinedTypes()) {
436 if (StartsWith(type->GetLocation().GetFile(), location)) {
437 types.push_back(type);
438 }
439 }
440 return types;
441 };
442 std::vector<const AidlDefinedType*> old_types =
443 get_types_in(*old_tns, options.InputFiles().at(0));
444 std::vector<const AidlDefinedType*> new_types =
445 get_types_in(*new_tns, options.InputFiles().at(1));
446
447 bool compatible = true;
448
449 if (level == Options::CheckApiLevel::EQUAL) {
450 std::set<string> old_type_names;
451 for (const auto t : old_types) {
452 old_type_names.insert(t->GetCanonicalName());
453 }
454 for (const auto new_type : new_types) {
455 const auto found = old_type_names.find(new_type->GetCanonicalName());
456 if (found == old_type_names.end()) {
457 AIDL_ERROR(new_type) << "Added type: " << new_type->GetCanonicalName();
458 compatible = false;
459 continue;
460 }
461 }
462 }
463
464 map<string, const AidlDefinedType*> new_map;
465 for (const auto t : new_types) {
466 new_map.emplace(t->GetCanonicalName(), t);
467 }
468
469 for (const auto old_type : old_types) {
470 const auto found = new_map.find(old_type->GetCanonicalName());
471 if (found == new_map.end()) {
472 AIDL_ERROR(old_type) << "Removed type: " << old_type->GetCanonicalName();
473 compatible = false;
474 continue;
475 }
476 const auto new_type = found->second;
477
478 if (level == Options::CheckApiLevel::EQUAL) {
479 if (!CheckEquality(*old_type, *new_type)) {
480 compatible = false;
481 }
482 continue;
483 }
484
485 if (!have_compatible_annotations(*old_type, *new_type)) {
486 compatible = false;
487 }
488 if (old_type->AsInterface() != nullptr) {
489 if (new_type->AsInterface() == nullptr) {
490 AIDL_ERROR(new_type) << "Type mismatch: " << old_type->GetCanonicalName()
491 << " is changed from " << old_type->GetPreprocessDeclarationName()
492 << " to " << new_type->GetPreprocessDeclarationName();
493 compatible = false;
494 continue;
495 }
496 compatible &=
497 are_compatible_interfaces(*(old_type->AsInterface()), *(new_type->AsInterface()));
498 } else if (old_type->AsStructuredParcelable() != nullptr) {
499 if (new_type->AsStructuredParcelable() == nullptr) {
500 AIDL_ERROR(new_type) << "Parcelable" << new_type->GetCanonicalName()
501 << " is not structured. ";
502 compatible = false;
503 continue;
504 }
505 compatible &= are_compatible_parcelables(*(old_type->AsStructuredParcelable()), *old_tns,
506 *(new_type->AsStructuredParcelable()), *new_tns);
507 } else if (old_type->AsUnionDeclaration() != nullptr) {
508 if (new_type->AsUnionDeclaration() == nullptr) {
509 AIDL_ERROR(new_type) << "Type mismatch: " << old_type->GetCanonicalName()
510 << " is changed from " << old_type->GetPreprocessDeclarationName()
511 << " to " << new_type->GetPreprocessDeclarationName();
512 compatible = false;
513 continue;
514 }
515 compatible &= are_compatible_parcelables(*(old_type->AsUnionDeclaration()), *old_tns,
516 *(new_type->AsUnionDeclaration()), *new_tns);
517 } else if (old_type->AsEnumDeclaration() != nullptr) {
518 if (new_type->AsEnumDeclaration() == nullptr) {
519 AIDL_ERROR(new_type) << "Type mismatch: " << old_type->GetCanonicalName()
520 << " is changed from " << old_type->GetPreprocessDeclarationName()
521 << " to " << new_type->GetPreprocessDeclarationName();
522 compatible = false;
523 continue;
524 }
525 compatible &=
526 are_compatible_enums(*(old_type->AsEnumDeclaration()), *(new_type->AsEnumDeclaration()));
527 } else {
528 AIDL_ERROR(old_type) << "Unsupported type " << old_type->GetPreprocessDeclarationName()
529 << " for " << old_type->GetCanonicalName();
530 compatible = false;
531 }
532 }
533
534 return compatible;
535 }
536
537 } // namespace aidl
538 } // namespace android
539