| /* |
| * Copyright (C) 2017 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| #include "class_loader_context.h" |
| |
| #include <stdlib.h> |
| |
| #include "android-base/file.h" |
| #include "art_field-inl.h" |
| #include "base/dchecked_vector.h" |
| #include "base/stl_util.h" |
| #include "class_linker.h" |
| #include "class_loader_utils.h" |
| #include "dex_file.h" |
| #include "handle_scope-inl.h" |
| #include "jni_internal.h" |
| #include "oat_file_assistant.h" |
| #include "obj_ptr-inl.h" |
| #include "runtime.h" |
| #include "scoped_thread_state_change-inl.h" |
| #include "thread.h" |
| #include "well_known_classes.h" |
| |
| namespace art { |
| |
| static constexpr char kPathClassLoaderString[] = "PCL"; |
| static constexpr char kDelegateLastClassLoaderString[] = "DLC"; |
| static constexpr char kClassLoaderOpeningMark = '['; |
| static constexpr char kClassLoaderClosingMark = ']'; |
| static constexpr char kClassLoaderSeparator = ';'; |
| static constexpr char kClasspathSeparator = ':'; |
| static constexpr char kDexFileChecksumSeparator = '*'; |
| |
| ClassLoaderContext::ClassLoaderContext() |
| : special_shared_library_(false), |
| dex_files_open_attempted_(false), |
| dex_files_open_result_(false), |
| owns_the_dex_files_(true) {} |
| |
| ClassLoaderContext::ClassLoaderContext(bool owns_the_dex_files) |
| : special_shared_library_(false), |
| dex_files_open_attempted_(true), |
| dex_files_open_result_(true), |
| owns_the_dex_files_(owns_the_dex_files) {} |
| |
| ClassLoaderContext::~ClassLoaderContext() { |
| if (!owns_the_dex_files_) { |
| // If the context does not own the dex/oat files release the unique pointers to |
| // make sure we do not de-allocate them. |
| for (ClassLoaderInfo& info : class_loader_chain_) { |
| for (std::unique_ptr<OatFile>& oat_file : info.opened_oat_files) { |
| oat_file.release(); |
| } |
| for (std::unique_ptr<const DexFile>& dex_file : info.opened_dex_files) { |
| dex_file.release(); |
| } |
| } |
| } |
| } |
| |
| std::unique_ptr<ClassLoaderContext> ClassLoaderContext::Default() { |
| return Create(""); |
| } |
| |
| std::unique_ptr<ClassLoaderContext> ClassLoaderContext::Create(const std::string& spec) { |
| std::unique_ptr<ClassLoaderContext> result(new ClassLoaderContext()); |
| if (result->Parse(spec)) { |
| return result; |
| } else { |
| return nullptr; |
| } |
| } |
| |
| // The expected format is: "ClassLoaderType1[ClasspathElem1*Checksum1:ClasspathElem2*Checksum2...]". |
| // The checksum part of the format is expected only if parse_cheksums is true. |
| bool ClassLoaderContext::ParseClassLoaderSpec(const std::string& class_loader_spec, |
| ClassLoaderType class_loader_type, |
| bool parse_checksums) { |
| const char* class_loader_type_str = GetClassLoaderTypeName(class_loader_type); |
| size_t type_str_size = strlen(class_loader_type_str); |
| |
| CHECK_EQ(0, class_loader_spec.compare(0, type_str_size, class_loader_type_str)); |
| |
| // Check the opening and closing markers. |
| if (class_loader_spec[type_str_size] != kClassLoaderOpeningMark) { |
| return false; |
| } |
| if (class_loader_spec[class_loader_spec.length() - 1] != kClassLoaderClosingMark) { |
| return false; |
| } |
| |
| // At this point we know the format is ok; continue and extract the classpath. |
| // Note that class loaders with an empty class path are allowed. |
| std::string classpath = class_loader_spec.substr(type_str_size + 1, |
| class_loader_spec.length() - type_str_size - 2); |
| |
| class_loader_chain_.push_back(ClassLoaderInfo(class_loader_type)); |
| |
| if (!parse_checksums) { |
| Split(classpath, kClasspathSeparator, &class_loader_chain_.back().classpath); |
| } else { |
| std::vector<std::string> classpath_elements; |
| Split(classpath, kClasspathSeparator, &classpath_elements); |
| for (const std::string& element : classpath_elements) { |
| std::vector<std::string> dex_file_with_checksum; |
| Split(element, kDexFileChecksumSeparator, &dex_file_with_checksum); |
| if (dex_file_with_checksum.size() != 2) { |
| return false; |
| } |
| uint32_t checksum = 0; |
| if (!ParseInt(dex_file_with_checksum[1].c_str(), &checksum)) { |
| return false; |
| } |
| class_loader_chain_.back().classpath.push_back(dex_file_with_checksum[0]); |
| class_loader_chain_.back().checksums.push_back(checksum); |
| } |
| } |
| |
| return true; |
| } |
| |
| // Extracts the class loader type from the given spec. |
| // Return ClassLoaderContext::kInvalidClassLoader if the class loader type is not |
| // recognized. |
| ClassLoaderContext::ClassLoaderType |
| ClassLoaderContext::ExtractClassLoaderType(const std::string& class_loader_spec) { |
| const ClassLoaderType kValidTypes[] = {kPathClassLoader, kDelegateLastClassLoader}; |
| for (const ClassLoaderType& type : kValidTypes) { |
| const char* type_str = GetClassLoaderTypeName(type); |
| if (class_loader_spec.compare(0, strlen(type_str), type_str) == 0) { |
| return type; |
| } |
| } |
| return kInvalidClassLoader; |
| } |
| |
| // The format: ClassLoaderType1[ClasspathElem1:ClasspathElem2...];ClassLoaderType2[...]... |
| // ClassLoaderType is either "PCL" (PathClassLoader) or "DLC" (DelegateLastClassLoader). |
| // ClasspathElem is the path of dex/jar/apk file. |
| bool ClassLoaderContext::Parse(const std::string& spec, bool parse_checksums) { |
| if (spec.empty()) { |
| // By default we load the dex files in a PathClassLoader. |
| // So an empty spec is equivalent to an empty PathClassLoader (this happens when running |
| // tests) |
| class_loader_chain_.push_back(ClassLoaderInfo(kPathClassLoader)); |
| return true; |
| } |
| |
| // Stop early if we detect the special shared library, which may be passed as the classpath |
| // for dex2oat when we want to skip the shared libraries check. |
| if (spec == OatFile::kSpecialSharedLibrary) { |
| LOG(INFO) << "The ClassLoaderContext is a special shared library."; |
| special_shared_library_ = true; |
| return true; |
| } |
| |
| std::vector<std::string> class_loaders; |
| Split(spec, kClassLoaderSeparator, &class_loaders); |
| |
| for (const std::string& class_loader : class_loaders) { |
| ClassLoaderType type = ExtractClassLoaderType(class_loader); |
| if (type == kInvalidClassLoader) { |
| LOG(ERROR) << "Invalid class loader type: " << class_loader; |
| return false; |
| } |
| if (!ParseClassLoaderSpec(class_loader, type, parse_checksums)) { |
| LOG(ERROR) << "Invalid class loader spec: " << class_loader; |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| // Opens requested class path files and appends them to opened_dex_files. If the dex files have |
| // been stripped, this opens them from their oat files (which get added to opened_oat_files). |
| bool ClassLoaderContext::OpenDexFiles(InstructionSet isa, const std::string& classpath_dir) { |
| if (dex_files_open_attempted_) { |
| // Do not attempt to re-open the files if we already tried. |
| return dex_files_open_result_; |
| } |
| |
| dex_files_open_attempted_ = true; |
| // Assume we can open all dex files. If not, we will set this to false as we go. |
| dex_files_open_result_ = true; |
| |
| if (special_shared_library_) { |
| // Nothing to open if the context is a special shared library. |
| return true; |
| } |
| |
| // Note that we try to open all dex files even if some fail. |
| // We may get resource-only apks which we cannot load. |
| // TODO(calin): Refine the dex opening interface to be able to tell if an archive contains |
| // no dex files. So that we can distinguish the real failures... |
| for (ClassLoaderInfo& info : class_loader_chain_) { |
| size_t opened_dex_files_index = info.opened_dex_files.size(); |
| for (const std::string& cp_elem : info.classpath) { |
| // If path is relative, append it to the provided base directory. |
| std::string raw_location = cp_elem; |
| if (raw_location[0] != '/' && !classpath_dir.empty()) { |
| raw_location = classpath_dir + '/' + raw_location; |
| } |
| |
| std::string location; // the real location of the class path element. |
| |
| if (!android::base::Realpath(raw_location, &location)) { |
| // If we can't get the realpath of the location there might be something wrong with the |
| // classpath (maybe the file was deleted). |
| // Do not continue in this case and return false. |
| PLOG(ERROR) << "Could not get the realpath of dex location " << raw_location; |
| return false; |
| } |
| |
| std::string error_msg; |
| // When opening the dex files from the context we expect their checksum to match their |
| // contents. So pass true to verify_checksum. |
| if (!DexFile::Open(location.c_str(), |
| location.c_str(), |
| /*verify_checksum*/ true, |
| &error_msg, |
| &info.opened_dex_files)) { |
| // If we fail to open the dex file because it's been stripped, try to open the dex file |
| // from its corresponding oat file. |
| // This could happen when we need to recompile a pre-build whose dex code has been stripped. |
| // (for example, if the pre-build is only quicken and we want to re-compile it |
| // speed-profile). |
| // TODO(calin): Use the vdex directly instead of going through the oat file. |
| OatFileAssistant oat_file_assistant(location.c_str(), isa, false); |
| std::unique_ptr<OatFile> oat_file(oat_file_assistant.GetBestOatFile()); |
| std::vector<std::unique_ptr<const DexFile>> oat_dex_files; |
| if (oat_file != nullptr && |
| OatFileAssistant::LoadDexFiles(*oat_file, location, &oat_dex_files)) { |
| info.opened_oat_files.push_back(std::move(oat_file)); |
| info.opened_dex_files.insert(info.opened_dex_files.end(), |
| std::make_move_iterator(oat_dex_files.begin()), |
| std::make_move_iterator(oat_dex_files.end())); |
| } else { |
| LOG(WARNING) << "Could not open dex files from location: " << location; |
| dex_files_open_result_ = false; |
| } |
| } |
| } |
| |
| // We finished opening the dex files from the classpath. |
| // Now update the classpath and the checksum with the locations of the dex files. |
| // |
| // We do this because initially the classpath contains the paths of the dex files; and |
| // some of them might be multi-dexes. So in order to have a consistent view we replace all the |
| // file paths with the actual dex locations being loaded. |
| // This will allow the context to VerifyClassLoaderContextMatch which expects or multidex |
| // location in the class paths. |
| // Note that this will also remove the paths that could not be opened. |
| info.classpath.clear(); |
| info.checksums.clear(); |
| for (size_t k = opened_dex_files_index; k < info.opened_dex_files.size(); k++) { |
| std::unique_ptr<const DexFile>& dex = info.opened_dex_files[k]; |
| info.classpath.push_back(dex->GetLocation()); |
| info.checksums.push_back(dex->GetLocationChecksum()); |
| } |
| } |
| |
| return dex_files_open_result_; |
| } |
| |
| bool ClassLoaderContext::RemoveLocationsFromClassPaths( |
| const dchecked_vector<std::string>& locations) { |
| CHECK(!dex_files_open_attempted_) |
| << "RemoveLocationsFromClasspaths cannot be call after OpenDexFiles"; |
| |
| std::set<std::string> canonical_locations; |
| for (const std::string& location : locations) { |
| canonical_locations.insert(DexFile::GetDexCanonicalLocation(location.c_str())); |
| } |
| bool removed_locations = false; |
| for (ClassLoaderInfo& info : class_loader_chain_) { |
| size_t initial_size = info.classpath.size(); |
| auto kept_it = std::remove_if( |
| info.classpath.begin(), |
| info.classpath.end(), |
| [canonical_locations](const std::string& location) { |
| return ContainsElement(canonical_locations, |
| DexFile::GetDexCanonicalLocation(location.c_str())); |
| }); |
| info.classpath.erase(kept_it, info.classpath.end()); |
| if (initial_size != info.classpath.size()) { |
| removed_locations = true; |
| } |
| } |
| return removed_locations; |
| } |
| |
| std::string ClassLoaderContext::EncodeContextForDex2oat(const std::string& base_dir) const { |
| return EncodeContext(base_dir, /*for_dex2oat*/ true); |
| } |
| |
| std::string ClassLoaderContext::EncodeContextForOatFile(const std::string& base_dir) const { |
| return EncodeContext(base_dir, /*for_dex2oat*/ false); |
| } |
| |
| std::string ClassLoaderContext::EncodeContext(const std::string& base_dir, |
| bool for_dex2oat) const { |
| CheckDexFilesOpened("EncodeContextForOatFile"); |
| if (special_shared_library_) { |
| return OatFile::kSpecialSharedLibrary; |
| } |
| |
| std::ostringstream out; |
| if (class_loader_chain_.empty()) { |
| // We can get in this situation if the context was created with a class path containing the |
| // source dex files which were later removed (happens during run-tests). |
| out << GetClassLoaderTypeName(kPathClassLoader) |
| << kClassLoaderOpeningMark |
| << kClassLoaderClosingMark; |
| return out.str(); |
| } |
| |
| for (size_t i = 0; i < class_loader_chain_.size(); i++) { |
| const ClassLoaderInfo& info = class_loader_chain_[i]; |
| if (i > 0) { |
| out << kClassLoaderSeparator; |
| } |
| out << GetClassLoaderTypeName(info.type); |
| out << kClassLoaderOpeningMark; |
| std::set<std::string> seen_locations; |
| for (size_t k = 0; k < info.opened_dex_files.size(); k++) { |
| const std::unique_ptr<const DexFile>& dex_file = info.opened_dex_files[k]; |
| if (for_dex2oat) { |
| // dex2oat only needs the base location. It cannot accept multidex locations. |
| // So ensure we only add each file once. |
| bool new_insert = seen_locations.insert(dex_file->GetBaseLocation()).second; |
| if (!new_insert) { |
| continue; |
| } |
| } |
| const std::string& location = dex_file->GetLocation(); |
| if (k > 0) { |
| out << kClasspathSeparator; |
| } |
| // Find paths that were relative and convert them back from absolute. |
| if (!base_dir.empty() && location.substr(0, base_dir.length()) == base_dir) { |
| out << location.substr(base_dir.length() + 1).c_str(); |
| } else { |
| out << dex_file->GetLocation().c_str(); |
| } |
| // dex2oat does not need the checksums. |
| if (!for_dex2oat) { |
| out << kDexFileChecksumSeparator; |
| out << dex_file->GetLocationChecksum(); |
| } |
| } |
| out << kClassLoaderClosingMark; |
| } |
| return out.str(); |
| } |
| |
| jobject ClassLoaderContext::CreateClassLoader( |
| const std::vector<const DexFile*>& compilation_sources) const { |
| CheckDexFilesOpened("CreateClassLoader"); |
| |
| Thread* self = Thread::Current(); |
| ScopedObjectAccess soa(self); |
| |
| ClassLinker* const class_linker = Runtime::Current()->GetClassLinker(); |
| |
| if (class_loader_chain_.empty()) { |
| return class_linker->CreatePathClassLoader(self, compilation_sources); |
| } |
| |
| // Create the class loaders starting from the top most parent (the one on the last position |
| // in the chain) but omit the first class loader which will contain the compilation_sources and |
| // needs special handling. |
| jobject current_parent = nullptr; // the starting parent is the BootClassLoader. |
| for (size_t i = class_loader_chain_.size() - 1; i > 0; i--) { |
| std::vector<const DexFile*> class_path_files = MakeNonOwningPointerVector( |
| class_loader_chain_[i].opened_dex_files); |
| current_parent = class_linker->CreateWellKnownClassLoader( |
| self, |
| class_path_files, |
| GetClassLoaderClass(class_loader_chain_[i].type), |
| current_parent); |
| } |
| |
| // We set up all the parents. Move on to create the first class loader. |
| // Its classpath comes first, followed by compilation sources. This ensures that whenever |
| // we need to resolve classes from it the classpath elements come first. |
| |
| std::vector<const DexFile*> first_class_loader_classpath = MakeNonOwningPointerVector( |
| class_loader_chain_[0].opened_dex_files); |
| first_class_loader_classpath.insert(first_class_loader_classpath.end(), |
| compilation_sources.begin(), |
| compilation_sources.end()); |
| |
| return class_linker->CreateWellKnownClassLoader( |
| self, |
| first_class_loader_classpath, |
| GetClassLoaderClass(class_loader_chain_[0].type), |
| current_parent); |
| } |
| |
| std::vector<const DexFile*> ClassLoaderContext::FlattenOpenedDexFiles() const { |
| CheckDexFilesOpened("FlattenOpenedDexFiles"); |
| |
| std::vector<const DexFile*> result; |
| for (const ClassLoaderInfo& info : class_loader_chain_) { |
| for (const std::unique_ptr<const DexFile>& dex_file : info.opened_dex_files) { |
| result.push_back(dex_file.get()); |
| } |
| } |
| return result; |
| } |
| |
| const char* ClassLoaderContext::GetClassLoaderTypeName(ClassLoaderType type) { |
| switch (type) { |
| case kPathClassLoader: return kPathClassLoaderString; |
| case kDelegateLastClassLoader: return kDelegateLastClassLoaderString; |
| default: |
| LOG(FATAL) << "Invalid class loader type " << type; |
| UNREACHABLE(); |
| } |
| } |
| |
| void ClassLoaderContext::CheckDexFilesOpened(const std::string& calling_method) const { |
| CHECK(dex_files_open_attempted_) |
| << "Dex files were not successfully opened before the call to " << calling_method |
| << "attempt=" << dex_files_open_attempted_ << ", result=" << dex_files_open_result_; |
| } |
| |
| // Collects the dex files from the give Java dex_file object. Only the dex files with |
| // at least 1 class are collected. If a null java_dex_file is passed this method does nothing. |
| static bool CollectDexFilesFromJavaDexFile(ObjPtr<mirror::Object> java_dex_file, |
| ArtField* const cookie_field, |
| std::vector<const DexFile*>* out_dex_files) |
| REQUIRES_SHARED(Locks::mutator_lock_) { |
| if (java_dex_file == nullptr) { |
| return true; |
| } |
| // On the Java side, the dex files are stored in the cookie field. |
| mirror::LongArray* long_array = cookie_field->GetObject(java_dex_file)->AsLongArray(); |
| if (long_array == nullptr) { |
| // This should never happen so log a warning. |
| LOG(ERROR) << "Unexpected null cookie"; |
| return false; |
| } |
| int32_t long_array_size = long_array->GetLength(); |
| // Index 0 from the long array stores the oat file. The dex files start at index 1. |
| for (int32_t j = 1; j < long_array_size; ++j) { |
| const DexFile* cp_dex_file = reinterpret_cast<const DexFile*>(static_cast<uintptr_t>( |
| long_array->GetWithoutChecks(j))); |
| if (cp_dex_file != nullptr && cp_dex_file->NumClassDefs() > 0) { |
| // TODO(calin): It's unclear why the dex files with no classes are skipped here and when |
| // cp_dex_file can be null. |
| out_dex_files->push_back(cp_dex_file); |
| } |
| } |
| return true; |
| } |
| |
| // Collects all the dex files loaded by the given class loader. |
| // Returns true for success or false if an unexpected state is discovered (e.g. a null dex cookie, |
| // a null list of dex elements or a null dex element). |
| static bool CollectDexFilesFromSupportedClassLoader(ScopedObjectAccessAlreadyRunnable& soa, |
| Handle<mirror::ClassLoader> class_loader, |
| std::vector<const DexFile*>* out_dex_files) |
| REQUIRES_SHARED(Locks::mutator_lock_) { |
| CHECK(IsPathOrDexClassLoader(soa, class_loader) || IsDelegateLastClassLoader(soa, class_loader)); |
| |
| // All supported class loaders inherit from BaseDexClassLoader. |
| // We need to get the DexPathList and loop through it. |
| ArtField* const cookie_field = |
| jni::DecodeArtField(WellKnownClasses::dalvik_system_DexFile_cookie); |
| ArtField* const dex_file_field = |
| jni::DecodeArtField(WellKnownClasses::dalvik_system_DexPathList__Element_dexFile); |
| ObjPtr<mirror::Object> dex_path_list = |
| jni::DecodeArtField(WellKnownClasses::dalvik_system_BaseDexClassLoader_pathList)-> |
| GetObject(class_loader.Get()); |
| CHECK(cookie_field != nullptr); |
| CHECK(dex_file_field != nullptr); |
| if (dex_path_list == nullptr) { |
| // This may be null if the current class loader is under construction and it does not |
| // have its fields setup yet. |
| return true; |
| } |
| // DexPathList has an array dexElements of Elements[] which each contain a dex file. |
| ObjPtr<mirror::Object> dex_elements_obj = |
| jni::DecodeArtField(WellKnownClasses::dalvik_system_DexPathList_dexElements)-> |
| GetObject(dex_path_list); |
| // Loop through each dalvik.system.DexPathList$Element's dalvik.system.DexFile and look |
| // at the mCookie which is a DexFile vector. |
| if (dex_elements_obj == nullptr) { |
| // TODO(calin): It's unclear if we should just assert here. For now be prepared for the worse |
| // and assume we have no elements. |
| return true; |
| } else { |
| StackHandleScope<1> hs(soa.Self()); |
| Handle<mirror::ObjectArray<mirror::Object>> dex_elements( |
| hs.NewHandle(dex_elements_obj->AsObjectArray<mirror::Object>())); |
| for (int32_t i = 0; i < dex_elements->GetLength(); ++i) { |
| mirror::Object* element = dex_elements->GetWithoutChecks(i); |
| if (element == nullptr) { |
| // Should never happen, log an error and break. |
| // TODO(calin): It's unclear if we should just assert here. |
| // This code was propagated to oat_file_manager from the class linker where it would |
| // throw a NPE. For now, return false which will mark this class loader as unsupported. |
| LOG(ERROR) << "Unexpected null in the dex element list"; |
| return false; |
| } |
| ObjPtr<mirror::Object> dex_file = dex_file_field->GetObject(element); |
| if (!CollectDexFilesFromJavaDexFile(dex_file, cookie_field, out_dex_files)) { |
| return false; |
| } |
| } |
| } |
| |
| return true; |
| } |
| |
| static bool GetDexFilesFromDexElementsArray( |
| ScopedObjectAccessAlreadyRunnable& soa, |
| Handle<mirror::ObjectArray<mirror::Object>> dex_elements, |
| std::vector<const DexFile*>* out_dex_files) REQUIRES_SHARED(Locks::mutator_lock_) { |
| DCHECK(dex_elements != nullptr); |
| |
| ArtField* const cookie_field = |
| jni::DecodeArtField(WellKnownClasses::dalvik_system_DexFile_cookie); |
| ArtField* const dex_file_field = |
| jni::DecodeArtField(WellKnownClasses::dalvik_system_DexPathList__Element_dexFile); |
| ObjPtr<mirror::Class> const element_class = soa.Decode<mirror::Class>( |
| WellKnownClasses::dalvik_system_DexPathList__Element); |
| ObjPtr<mirror::Class> const dexfile_class = soa.Decode<mirror::Class>( |
| WellKnownClasses::dalvik_system_DexFile); |
| |
| for (int32_t i = 0; i < dex_elements->GetLength(); ++i) { |
| mirror::Object* element = dex_elements->GetWithoutChecks(i); |
| // We can hit a null element here because this is invoked with a partially filled dex_elements |
| // array from DexPathList. DexPathList will open each dex sequentially, each time passing the |
| // list of dex files which were opened before. |
| if (element == nullptr) { |
| continue; |
| } |
| |
| // We support this being dalvik.system.DexPathList$Element and dalvik.system.DexFile. |
| // TODO(calin): Code caried over oat_file_manager: supporting both classes seem to be |
| // a historical glitch. All the java code opens dex files using an array of Elements. |
| ObjPtr<mirror::Object> dex_file; |
| if (element_class == element->GetClass()) { |
| dex_file = dex_file_field->GetObject(element); |
| } else if (dexfile_class == element->GetClass()) { |
| dex_file = element; |
| } else { |
| LOG(ERROR) << "Unsupported element in dex_elements: " |
| << mirror::Class::PrettyClass(element->GetClass()); |
| return false; |
| } |
| |
| if (!CollectDexFilesFromJavaDexFile(dex_file, cookie_field, out_dex_files)) { |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| // Adds the `class_loader` info to the `context`. |
| // The dex file present in `dex_elements` array (if not null) will be added at the end of |
| // the classpath. |
| // This method is recursive (w.r.t. the class loader parent) and will stop once it reaches the |
| // BootClassLoader. Note that the class loader chain is expected to be short. |
| bool ClassLoaderContext::AddInfoToContextFromClassLoader( |
| ScopedObjectAccessAlreadyRunnable& soa, |
| Handle<mirror::ClassLoader> class_loader, |
| Handle<mirror::ObjectArray<mirror::Object>> dex_elements) |
| REQUIRES_SHARED(Locks::mutator_lock_) { |
| if (ClassLinker::IsBootClassLoader(soa, class_loader.Get())) { |
| // Nothing to do for the boot class loader as we don't add its dex files to the context. |
| return true; |
| } |
| |
| ClassLoaderContext::ClassLoaderType type; |
| if (IsPathOrDexClassLoader(soa, class_loader)) { |
| type = kPathClassLoader; |
| } else if (IsDelegateLastClassLoader(soa, class_loader)) { |
| type = kDelegateLastClassLoader; |
| } else { |
| LOG(WARNING) << "Unsupported class loader"; |
| return false; |
| } |
| |
| // Inspect the class loader for its dex files. |
| std::vector<const DexFile*> dex_files_loaded; |
| CollectDexFilesFromSupportedClassLoader(soa, class_loader, &dex_files_loaded); |
| |
| // If we have a dex_elements array extract its dex elements now. |
| // This is used in two situations: |
| // 1) when a new ClassLoader is created DexPathList will open each dex file sequentially |
| // passing the list of already open dex files each time. This ensures that we see the |
| // correct context even if the ClassLoader under construction is not fully build. |
| // 2) when apk splits are loaded on the fly, the framework will load their dex files by |
| // appending them to the current class loader. When the new code paths are loaded in |
| // BaseDexClassLoader, the paths already present in the class loader will be passed |
| // in the dex_elements array. |
| if (dex_elements != nullptr) { |
| GetDexFilesFromDexElementsArray(soa, dex_elements, &dex_files_loaded); |
| } |
| |
| class_loader_chain_.push_back(ClassLoaderContext::ClassLoaderInfo(type)); |
| ClassLoaderInfo& info = class_loader_chain_.back(); |
| for (const DexFile* dex_file : dex_files_loaded) { |
| info.classpath.push_back(dex_file->GetLocation()); |
| info.checksums.push_back(dex_file->GetLocationChecksum()); |
| info.opened_dex_files.emplace_back(dex_file); |
| } |
| |
| // We created the ClassLoaderInfo for the current loader. Move on to its parent. |
| |
| StackHandleScope<1> hs(Thread::Current()); |
| Handle<mirror::ClassLoader> parent = hs.NewHandle(class_loader->GetParent()); |
| |
| // Note that dex_elements array is null here. The elements are considered to be part of the |
| // current class loader and are not passed to the parents. |
| ScopedNullHandle<mirror::ObjectArray<mirror::Object>> null_dex_elements; |
| return AddInfoToContextFromClassLoader(soa, parent, null_dex_elements); |
| } |
| |
| std::unique_ptr<ClassLoaderContext> ClassLoaderContext::CreateContextForClassLoader( |
| jobject class_loader, |
| jobjectArray dex_elements) { |
| CHECK(class_loader != nullptr); |
| |
| ScopedObjectAccess soa(Thread::Current()); |
| StackHandleScope<2> hs(soa.Self()); |
| Handle<mirror::ClassLoader> h_class_loader = |
| hs.NewHandle(soa.Decode<mirror::ClassLoader>(class_loader)); |
| Handle<mirror::ObjectArray<mirror::Object>> h_dex_elements = |
| hs.NewHandle(soa.Decode<mirror::ObjectArray<mirror::Object>>(dex_elements)); |
| |
| std::unique_ptr<ClassLoaderContext> result(new ClassLoaderContext(/*owns_the_dex_files*/ false)); |
| if (result->AddInfoToContextFromClassLoader(soa, h_class_loader, h_dex_elements)) { |
| return result; |
| } else { |
| return nullptr; |
| } |
| } |
| |
| static bool IsAbsoluteLocation(const std::string& location) { |
| return !location.empty() && location[0] == '/'; |
| } |
| |
| bool ClassLoaderContext::VerifyClassLoaderContextMatch(const std::string& context_spec) const { |
| DCHECK(dex_files_open_attempted_); |
| DCHECK(dex_files_open_result_); |
| |
| ClassLoaderContext expected_context; |
| if (!expected_context.Parse(context_spec, /*parse_checksums*/ true)) { |
| LOG(WARNING) << "Invalid class loader context: " << context_spec; |
| return false; |
| } |
| |
| // Special shared library contexts always match. They essentially instruct the runtime |
| // to ignore the class path check because the oat file is known to be loaded in different |
| // contexts. OatFileManager will further verify if the oat file can be loaded based on the |
| // collision check. |
| if (special_shared_library_ || expected_context.special_shared_library_) { |
| return true; |
| } |
| |
| if (expected_context.class_loader_chain_.size() != class_loader_chain_.size()) { |
| LOG(WARNING) << "ClassLoaderContext size mismatch. expected=" |
| << expected_context.class_loader_chain_.size() |
| << ", actual=" << class_loader_chain_.size() |
| << " (" << context_spec << " | " << EncodeContextForOatFile("") << ")"; |
| return false; |
| } |
| |
| for (size_t i = 0; i < class_loader_chain_.size(); i++) { |
| const ClassLoaderInfo& info = class_loader_chain_[i]; |
| const ClassLoaderInfo& expected_info = expected_context.class_loader_chain_[i]; |
| if (info.type != expected_info.type) { |
| LOG(WARNING) << "ClassLoaderContext type mismatch for position " << i |
| << ". expected=" << GetClassLoaderTypeName(expected_info.type) |
| << ", found=" << GetClassLoaderTypeName(info.type) |
| << " (" << context_spec << " | " << EncodeContextForOatFile("") << ")"; |
| return false; |
| } |
| if (info.classpath.size() != expected_info.classpath.size()) { |
| LOG(WARNING) << "ClassLoaderContext classpath size mismatch for position " << i |
| << ". expected=" << expected_info.classpath.size() |
| << ", found=" << info.classpath.size() |
| << " (" << context_spec << " | " << EncodeContextForOatFile("") << ")"; |
| return false; |
| } |
| |
| DCHECK_EQ(info.classpath.size(), info.checksums.size()); |
| DCHECK_EQ(expected_info.classpath.size(), expected_info.checksums.size()); |
| |
| for (size_t k = 0; k < info.classpath.size(); k++) { |
| // Compute the dex location that must be compared. |
| // We shouldn't do a naive comparison `info.classpath[k] == expected_info.classpath[k]` |
| // because even if they refer to the same file, one could be encoded as a relative location |
| // and the other as an absolute one. |
| bool is_dex_name_absolute = IsAbsoluteLocation(info.classpath[k]); |
| bool is_expected_dex_name_absolute = IsAbsoluteLocation(expected_info.classpath[k]); |
| std::string dex_name; |
| std::string expected_dex_name; |
| |
| if (is_dex_name_absolute == is_expected_dex_name_absolute) { |
| // If both locations are absolute or relative then compare them as they are. |
| // This is usually the case for: shared libraries and secondary dex files. |
| dex_name = info.classpath[k]; |
| expected_dex_name = expected_info.classpath[k]; |
| } else if (is_dex_name_absolute) { |
| // The runtime name is absolute but the compiled name (the expected one) is relative. |
| // This is the case for split apks which depend on base or on other splits. |
| dex_name = info.classpath[k]; |
| expected_dex_name = OatFile::ResolveRelativeEncodedDexLocation( |
| info.classpath[k].c_str(), expected_info.classpath[k]); |
| } else { |
| // The runtime name is relative but the compiled name is absolute. |
| // There is no expected use case that would end up here as dex files are always loaded |
| // with their absolute location. However, be tolerant and do the best effort (in case |
| // there are unexpected new use case...). |
| DCHECK(is_expected_dex_name_absolute); |
| dex_name = OatFile::ResolveRelativeEncodedDexLocation( |
| expected_info.classpath[k].c_str(), info.classpath[k]); |
| expected_dex_name = expected_info.classpath[k]; |
| } |
| |
| // Compare the locations. |
| if (dex_name != expected_dex_name) { |
| LOG(WARNING) << "ClassLoaderContext classpath element mismatch for position " << i |
| << ". expected=" << expected_info.classpath[k] |
| << ", found=" << info.classpath[k] |
| << " (" << context_spec << " | " << EncodeContextForOatFile("") << ")"; |
| return false; |
| } |
| |
| // Compare the checksums. |
| if (info.checksums[k] != expected_info.checksums[k]) { |
| LOG(WARNING) << "ClassLoaderContext classpath element checksum mismatch for position " << i |
| << ". expected=" << expected_info.checksums[k] |
| << ", found=" << info.checksums[k] |
| << " (" << context_spec << " | " << EncodeContextForOatFile("") << ")"; |
| return false; |
| } |
| } |
| } |
| return true; |
| } |
| |
| jclass ClassLoaderContext::GetClassLoaderClass(ClassLoaderType type) { |
| switch (type) { |
| case kPathClassLoader: return WellKnownClasses::dalvik_system_PathClassLoader; |
| case kDelegateLastClassLoader: return WellKnownClasses::dalvik_system_DelegateLastClassLoader; |
| case kInvalidClassLoader: break; // will fail after the switch. |
| } |
| LOG(FATAL) << "Invalid class loader type " << type; |
| UNREACHABLE(); |
| } |
| |
| } // namespace art |
| |