/* * Copyright (C) 2011 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 "dex_file.h" #include #include #include #include #include #include #include #include #include #include "android-base/stringprintf.h" #include "base/enums.h" #include "base/hiddenapi_domain.h" #include "base/leb128.h" #include "base/stl_util.h" #include "class_accessor-inl.h" #include "descriptors_names.h" #include "dex_file-inl.h" #include "standard_dex_file.h" #include "utf-inl.h" namespace art { using android::base::StringPrintf; using dex::CallSiteIdItem; using dex::ClassDef; using dex::FieldId; using dex::MapList; using dex::MapItem; using dex::MethodHandleItem; using dex::MethodId; using dex::ProtoId; using dex::StringId; using dex::TryItem; using dex::TypeId; using dex::TypeList; static_assert(sizeof(dex::StringIndex) == sizeof(uint32_t), "StringIndex size is wrong"); static_assert(std::is_trivially_copyable::value, "StringIndex not trivial"); static_assert(sizeof(dex::TypeIndex) == sizeof(uint16_t), "TypeIndex size is wrong"); static_assert(std::is_trivially_copyable::value, "TypeIndex not trivial"); uint32_t DexFile::CalculateChecksum() const { return CalculateChecksum(Begin(), Size()); } uint32_t DexFile::CalculateChecksum(const uint8_t* begin, size_t size) { const uint32_t non_sum_bytes = OFFSETOF_MEMBER(DexFile::Header, signature_); return ChecksumMemoryRange(begin + non_sum_bytes, size - non_sum_bytes); } uint32_t DexFile::ChecksumMemoryRange(const uint8_t* begin, size_t size) { return adler32(adler32(0L, Z_NULL, 0), begin, size); } int DexFile::GetPermissions() const { CHECK(container_.get() != nullptr); return container_->GetPermissions(); } bool DexFile::IsReadOnly() const { CHECK(container_.get() != nullptr); return container_->IsReadOnly(); } bool DexFile::EnableWrite() const { CHECK(container_.get() != nullptr); return container_->EnableWrite(); } bool DexFile::DisableWrite() const { CHECK(container_.get() != nullptr); return container_->DisableWrite(); } DexFile::DexFile(const uint8_t* base, size_t size, const uint8_t* data_begin, size_t data_size, const std::string& location, uint32_t location_checksum, const OatDexFile* oat_dex_file, std::unique_ptr container, bool is_compact_dex) : begin_(base), size_(size), data_begin_(data_begin), data_size_(data_size), location_(location), location_checksum_(location_checksum), header_(reinterpret_cast(base)), string_ids_(reinterpret_cast(base + header_->string_ids_off_)), type_ids_(reinterpret_cast(base + header_->type_ids_off_)), field_ids_(reinterpret_cast(base + header_->field_ids_off_)), method_ids_(reinterpret_cast(base + header_->method_ids_off_)), proto_ids_(reinterpret_cast(base + header_->proto_ids_off_)), class_defs_(reinterpret_cast(base + header_->class_defs_off_)), method_handles_(nullptr), num_method_handles_(0), call_site_ids_(nullptr), num_call_site_ids_(0), hiddenapi_class_data_(nullptr), oat_dex_file_(oat_dex_file), container_(std::move(container)), is_compact_dex_(is_compact_dex), hiddenapi_domain_(hiddenapi::Domain::kApplication) { CHECK(begin_ != nullptr) << GetLocation(); CHECK_GT(size_, 0U) << GetLocation(); // Check base (=header) alignment. // Must be 4-byte aligned to avoid undefined behavior when accessing // any of the sections via a pointer. CHECK_ALIGNED(begin_, alignof(Header)); if (DataSize() < sizeof(Header)) { // Don't go further if the data doesn't even contain a header. return; } InitializeSectionsFromMapList(); } DexFile::~DexFile() { // We don't call DeleteGlobalRef on dex_object_ because we're only called by DestroyJavaVM, and // that's only called after DetachCurrentThread, which means there's no JNIEnv. We could // re-attach, but cleaning up these global references is not obviously useful. It's not as if // the global reference table is otherwise empty! } bool DexFile::Init(std::string* error_msg) { if (!CheckMagicAndVersion(error_msg)) { return false; } return true; } bool DexFile::CheckMagicAndVersion(std::string* error_msg) const { if (!IsMagicValid()) { std::ostringstream oss; oss << "Unrecognized magic number in " << GetLocation() << ":" << " " << header_->magic_[0] << " " << header_->magic_[1] << " " << header_->magic_[2] << " " << header_->magic_[3]; *error_msg = oss.str(); return false; } if (!IsVersionValid()) { std::ostringstream oss; oss << "Unrecognized version number in " << GetLocation() << ":" << " " << header_->magic_[4] << " " << header_->magic_[5] << " " << header_->magic_[6] << " " << header_->magic_[7]; *error_msg = oss.str(); return false; } return true; } void DexFile::InitializeSectionsFromMapList() { static_assert(sizeof(MapList) <= sizeof(Header)); DCHECK_GE(DataSize(), sizeof(MapList)); if (header_->map_off_ == 0 || header_->map_off_ > DataSize() - sizeof(MapList)) { // Bad offset. The dex file verifier runs after this method and will reject the file. return; } const MapList* map_list = reinterpret_cast(DataBegin() + header_->map_off_); const size_t count = map_list->size_; size_t map_limit = header_->map_off_ + count * sizeof(MapItem); if (header_->map_off_ >= map_limit || map_limit > DataSize()) { // Overflow or out out of bounds. The dex file verifier runs after // this method and will reject the file as it is malformed. return; } for (size_t i = 0; i < count; ++i) { const MapItem& map_item = map_list->list_[i]; if (map_item.type_ == kDexTypeMethodHandleItem) { method_handles_ = reinterpret_cast(Begin() + map_item.offset_); num_method_handles_ = map_item.size_; } else if (map_item.type_ == kDexTypeCallSiteIdItem) { call_site_ids_ = reinterpret_cast(Begin() + map_item.offset_); num_call_site_ids_ = map_item.size_; } else if (map_item.type_ == kDexTypeHiddenapiClassData) { hiddenapi_class_data_ = GetHiddenapiClassDataAtOffset(map_item.offset_); } else { // Pointers to other sections are not necessary to retain in the DexFile struct. // Other items have pointers directly into their data. } } } uint32_t DexFile::Header::GetVersion() const { const char* version = reinterpret_cast(&magic_[kDexMagicSize]); return atoi(version); } const ClassDef* DexFile::FindClassDef(dex::TypeIndex type_idx) const { size_t num_class_defs = NumClassDefs(); // Fast path for rare no class defs case. if (num_class_defs == 0) { return nullptr; } for (size_t i = 0; i < num_class_defs; ++i) { const ClassDef& class_def = GetClassDef(i); if (class_def.class_idx_ == type_idx) { return &class_def; } } return nullptr; } std::optional DexFile::GetCodeItemOffset(const ClassDef &class_def, uint32_t method_idx) const { ClassAccessor accessor(*this, class_def); CHECK(accessor.HasClassData()); for (const ClassAccessor::Method &method : accessor.GetMethods()) { if (method.GetIndex() == method_idx) { return method.GetCodeItemOffset(); } } return std::nullopt; } uint32_t DexFile::FindCodeItemOffset(const dex::ClassDef &class_def, uint32_t dex_method_idx) const { std::optional val = GetCodeItemOffset(class_def, dex_method_idx); CHECK(val.has_value()) << "Unable to find method " << dex_method_idx; return *val; } const FieldId* DexFile::FindFieldId(const TypeId& declaring_klass, const StringId& name, const TypeId& type) const { // Binary search MethodIds knowing that they are sorted by class_idx, name_idx then proto_idx const dex::TypeIndex class_idx = GetIndexForTypeId(declaring_klass); const dex::StringIndex name_idx = GetIndexForStringId(name); const dex::TypeIndex type_idx = GetIndexForTypeId(type); int32_t lo = 0; int32_t hi = NumFieldIds() - 1; while (hi >= lo) { int32_t mid = (hi + lo) / 2; const FieldId& field = GetFieldId(mid); if (class_idx > field.class_idx_) { lo = mid + 1; } else if (class_idx < field.class_idx_) { hi = mid - 1; } else { if (name_idx > field.name_idx_) { lo = mid + 1; } else if (name_idx < field.name_idx_) { hi = mid - 1; } else { if (type_idx > field.type_idx_) { lo = mid + 1; } else if (type_idx < field.type_idx_) { hi = mid - 1; } else { return &field; } } } } return nullptr; } const MethodId* DexFile::FindMethodId(const TypeId& declaring_klass, const StringId& name, const ProtoId& signature) const { // Binary search MethodIds knowing that they are sorted by class_idx, name_idx then proto_idx const dex::TypeIndex class_idx = GetIndexForTypeId(declaring_klass); const dex::StringIndex name_idx = GetIndexForStringId(name); const dex::ProtoIndex proto_idx = GetIndexForProtoId(signature); return FindMethodIdByIndex(class_idx, name_idx, proto_idx); } const MethodId* DexFile::FindMethodIdByIndex(dex::TypeIndex class_idx, dex::StringIndex name_idx, dex::ProtoIndex proto_idx) const { // Binary search MethodIds knowing that they are sorted by class_idx, name_idx then proto_idx int32_t lo = 0; int32_t hi = NumMethodIds() - 1; while (hi >= lo) { int32_t mid = (hi + lo) / 2; const MethodId& method = GetMethodId(mid); if (class_idx > method.class_idx_) { lo = mid + 1; } else if (class_idx < method.class_idx_) { hi = mid - 1; } else { if (name_idx > method.name_idx_) { lo = mid + 1; } else if (name_idx < method.name_idx_) { hi = mid - 1; } else { if (proto_idx > method.proto_idx_) { lo = mid + 1; } else if (proto_idx < method.proto_idx_) { hi = mid - 1; } else { DCHECK_EQ(class_idx, method.class_idx_); DCHECK_EQ(proto_idx, method.proto_idx_); DCHECK_EQ(name_idx, method.name_idx_); return &method; } } } } return nullptr; } const StringId* DexFile::FindStringId(const char* string) const { int32_t lo = 0; int32_t hi = NumStringIds() - 1; while (hi >= lo) { int32_t mid = (hi + lo) / 2; const StringId& str_id = GetStringId(dex::StringIndex(mid)); const char* str = GetStringData(str_id); int compare = CompareModifiedUtf8ToModifiedUtf8AsUtf16CodePointValues(string, str); if (compare > 0) { lo = mid + 1; } else if (compare < 0) { hi = mid - 1; } else { return &str_id; } } return nullptr; } const TypeId* DexFile::FindTypeId(const char* string) const { int32_t lo = 0; int32_t hi = NumTypeIds() - 1; while (hi >= lo) { int32_t mid = (hi + lo) / 2; const TypeId& type_id = GetTypeId(dex::TypeIndex(mid)); const StringId& str_id = GetStringId(type_id.descriptor_idx_); const char* str = GetStringData(str_id); int compare = CompareModifiedUtf8ToModifiedUtf8AsUtf16CodePointValues(string, str); if (compare > 0) { lo = mid + 1; } else if (compare < 0) { hi = mid - 1; } else { return &type_id; } } return nullptr; } const TypeId* DexFile::FindTypeId(dex::StringIndex string_idx) const { int32_t lo = 0; int32_t hi = NumTypeIds() - 1; while (hi >= lo) { int32_t mid = (hi + lo) / 2; const TypeId& type_id = GetTypeId(dex::TypeIndex(mid)); if (string_idx > type_id.descriptor_idx_) { lo = mid + 1; } else if (string_idx < type_id.descriptor_idx_) { hi = mid - 1; } else { return &type_id; } } return nullptr; } const ProtoId* DexFile::FindProtoId(dex::TypeIndex return_type_idx, const dex::TypeIndex* signature_type_idxs, uint32_t signature_length) const { int32_t lo = 0; int32_t hi = NumProtoIds() - 1; while (hi >= lo) { int32_t mid = (hi + lo) / 2; const dex::ProtoIndex proto_idx = static_cast(mid); const ProtoId& proto = GetProtoId(proto_idx); int compare = return_type_idx.index_ - proto.return_type_idx_.index_; if (compare == 0) { DexFileParameterIterator it(*this, proto); size_t i = 0; while (it.HasNext() && i < signature_length && compare == 0) { compare = signature_type_idxs[i].index_ - it.GetTypeIdx().index_; it.Next(); i++; } if (compare == 0) { if (it.HasNext()) { compare = -1; } else if (i < signature_length) { compare = 1; } } } if (compare > 0) { lo = mid + 1; } else if (compare < 0) { hi = mid - 1; } else { return &proto; } } return nullptr; } // Given a signature place the type ids into the given vector bool DexFile::CreateTypeList(std::string_view signature, dex::TypeIndex* return_type_idx, std::vector* param_type_idxs) const { if (signature[0] != '(') { return false; } size_t offset = 1; size_t end = signature.size(); bool process_return = false; while (offset < end) { size_t start_offset = offset; char c = signature[offset]; offset++; if (c == ')') { process_return = true; continue; } while (c == '[') { // process array prefix if (offset >= end) { // expect some descriptor following [ return false; } c = signature[offset]; offset++; } if (c == 'L') { // process type descriptors do { if (offset >= end) { // unexpected early termination of descriptor return false; } c = signature[offset]; offset++; } while (c != ';'); } // TODO: avoid creating a std::string just to get a 0-terminated char array std::string descriptor(signature.data() + start_offset, offset - start_offset); const TypeId* type_id = FindTypeId(descriptor.c_str()); if (type_id == nullptr) { return false; } dex::TypeIndex type_idx = GetIndexForTypeId(*type_id); if (!process_return) { param_type_idxs->push_back(type_idx); } else { *return_type_idx = type_idx; return offset == end; // return true if the signature had reached a sensible end } } return false; // failed to correctly parse return type } int32_t DexFile::FindTryItem(const TryItem* try_items, uint32_t tries_size, uint32_t address) { uint32_t min = 0; uint32_t max = tries_size; while (min < max) { const uint32_t mid = (min + max) / 2; const TryItem& ti = try_items[mid]; const uint32_t start = ti.start_addr_; const uint32_t end = start + ti.insn_count_; if (address < start) { max = mid; } else if (address >= end) { min = mid + 1; } else { // We have a winner! return mid; } } // No match. return -1; } // Read a signed integer. "zwidth" is the zero-based byte count. int32_t DexFile::ReadSignedInt(const uint8_t* ptr, int zwidth) { int32_t val = 0; for (int i = zwidth; i >= 0; --i) { val = ((uint32_t)val >> 8) | (((int32_t)*ptr++) << 24); } val >>= (3 - zwidth) * 8; return val; } // Read an unsigned integer. "zwidth" is the zero-based byte count, // "fill_on_right" indicates which side we want to zero-fill from. uint32_t DexFile::ReadUnsignedInt(const uint8_t* ptr, int zwidth, bool fill_on_right) { uint32_t val = 0; for (int i = zwidth; i >= 0; --i) { val = (val >> 8) | (((uint32_t)*ptr++) << 24); } if (!fill_on_right) { val >>= (3 - zwidth) * 8; } return val; } // Read a signed long. "zwidth" is the zero-based byte count. int64_t DexFile::ReadSignedLong(const uint8_t* ptr, int zwidth) { int64_t val = 0; for (int i = zwidth; i >= 0; --i) { val = ((uint64_t)val >> 8) | (((int64_t)*ptr++) << 56); } val >>= (7 - zwidth) * 8; return val; } // Read an unsigned long. "zwidth" is the zero-based byte count, // "fill_on_right" indicates which side we want to zero-fill from. uint64_t DexFile::ReadUnsignedLong(const uint8_t* ptr, int zwidth, bool fill_on_right) { uint64_t val = 0; for (int i = zwidth; i >= 0; --i) { val = (val >> 8) | (((uint64_t)*ptr++) << 56); } if (!fill_on_right) { val >>= (7 - zwidth) * 8; } return val; } void DexFile::AppendPrettyMethod(uint32_t method_idx, bool with_signature, std::string* const result) const { if (method_idx >= NumMethodIds()) { android::base::StringAppendF(result, "<>", method_idx); return; } const MethodId& method_id = GetMethodId(method_idx); const ProtoId* proto_id = with_signature ? &GetProtoId(method_id.proto_idx_) : nullptr; if (with_signature) { AppendPrettyDescriptor(StringByTypeIdx(proto_id->return_type_idx_), result); result->push_back(' '); } AppendPrettyDescriptor(GetMethodDeclaringClassDescriptor(method_id), result); result->push_back('.'); result->append(GetMethodName(method_id)); if (with_signature) { result->push_back('('); const TypeList* params = GetProtoParameters(*proto_id); if (params != nullptr) { const char* separator = ""; for (uint32_t i = 0u, size = params->Size(); i != size; ++i) { result->append(separator); separator = ", "; AppendPrettyDescriptor(StringByTypeIdx(params->GetTypeItem(i).type_idx_), result); } } result->push_back(')'); } } std::string DexFile::PrettyField(uint32_t field_idx, bool with_type) const { if (field_idx >= NumFieldIds()) { return StringPrintf("<>", field_idx); } const FieldId& field_id = GetFieldId(field_idx); std::string result; if (with_type) { result += GetFieldTypeDescriptor(field_id); result += ' '; } AppendPrettyDescriptor(GetFieldDeclaringClassDescriptor(field_id), &result); result += '.'; result += GetFieldName(field_id); return result; } std::string DexFile::PrettyType(dex::TypeIndex type_idx) const { if (type_idx.index_ >= NumTypeIds()) { return StringPrintf("<>", type_idx.index_); } const TypeId& type_id = GetTypeId(type_idx); return PrettyDescriptor(GetTypeDescriptor(type_id)); } dex::ProtoIndex DexFile::GetProtoIndexForCallSite(uint32_t call_site_idx) const { const CallSiteIdItem& csi = GetCallSiteId(call_site_idx); CallSiteArrayValueIterator it(*this, csi); it.Next(); it.Next(); DCHECK_EQ(EncodedArrayValueIterator::ValueType::kMethodType, it.GetValueType()); return dex::ProtoIndex(it.GetJavaValue().i); } // Checks that visibility is as expected. Includes special behavior for M and // before to allow runtime and build visibility when expecting runtime. std::ostream& operator<<(std::ostream& os, const DexFile& dex_file) { os << StringPrintf("[DexFile: %s dex-checksum=%08x location-checksum=%08x %p-%p]", dex_file.GetLocation().c_str(), dex_file.GetHeader().checksum_, dex_file.GetLocationChecksum(), dex_file.Begin(), dex_file.Begin() + dex_file.Size()); return os; } EncodedArrayValueIterator::EncodedArrayValueIterator(const DexFile& dex_file, const uint8_t* array_data) : dex_file_(dex_file), array_size_(), pos_(-1), ptr_(array_data), type_(kByte) { array_size_ = (ptr_ != nullptr) ? DecodeUnsignedLeb128(&ptr_) : 0; if (array_size_ > 0) { Next(); } } void EncodedArrayValueIterator::Next() { pos_++; if (pos_ >= array_size_) { return; } uint8_t value_type = *ptr_++; uint8_t value_arg = value_type >> kEncodedValueArgShift; size_t width = value_arg + 1; // assume and correct later type_ = static_cast(value_type & kEncodedValueTypeMask); switch (type_) { case kBoolean: jval_.i = (value_arg != 0) ? 1 : 0; width = 0; break; case kByte: jval_.i = DexFile::ReadSignedInt(ptr_, value_arg); CHECK(IsInt<8>(jval_.i)); break; case kShort: jval_.i = DexFile::ReadSignedInt(ptr_, value_arg); CHECK(IsInt<16>(jval_.i)); break; case kChar: jval_.i = DexFile::ReadUnsignedInt(ptr_, value_arg, false); CHECK(IsUint<16>(jval_.i)); break; case kInt: jval_.i = DexFile::ReadSignedInt(ptr_, value_arg); break; case kLong: jval_.j = DexFile::ReadSignedLong(ptr_, value_arg); break; case kFloat: jval_.i = DexFile::ReadUnsignedInt(ptr_, value_arg, true); break; case kDouble: jval_.j = DexFile::ReadUnsignedLong(ptr_, value_arg, true); break; case kString: case kType: case kMethodType: case kMethodHandle: jval_.i = DexFile::ReadUnsignedInt(ptr_, value_arg, false); break; case kField: case kMethod: case kEnum: case kArray: case kAnnotation: UNIMPLEMENTED(FATAL) << ": type " << type_; UNREACHABLE(); case kNull: jval_.l = nullptr; width = 0; break; default: LOG(FATAL) << "Unreached"; UNREACHABLE(); } ptr_ += width; } namespace dex { std::ostream& operator<<(std::ostream& os, const ProtoIndex& index) { os << "ProtoIndex[" << index.index_ << "]"; return os; } std::ostream& operator<<(std::ostream& os, const StringIndex& index) { os << "StringIndex[" << index.index_ << "]"; return os; } std::ostream& operator<<(std::ostream& os, const TypeIndex& index) { os << "TypeIndex[" << index.index_ << "]"; return os; } } // namespace dex } // namespace art