|  | /* | 
|  | * 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 "format/Container.h" | 
|  |  | 
|  | #include "android-base/scopeguard.h" | 
|  | #include "android-base/stringprintf.h" | 
|  |  | 
|  | #include "trace/TraceBuffer.h" | 
|  |  | 
|  | using ::android::base::StringPrintf; | 
|  | using ::google::protobuf::io::CodedInputStream; | 
|  | using ::google::protobuf::io::CodedOutputStream; | 
|  | using ::google::protobuf::io::ZeroCopyOutputStream; | 
|  |  | 
|  | namespace aapt { | 
|  |  | 
|  | constexpr const static uint32_t kContainerFormatMagic = 0x54504141u; | 
|  | constexpr const static uint32_t kContainerFormatVersion = 1u; | 
|  | constexpr const static size_t kPaddingAlignment = 4u; | 
|  |  | 
|  | ContainerWriter::ContainerWriter(ZeroCopyOutputStream* out, size_t entry_count) | 
|  | : out_(out), total_entry_count_(entry_count), current_entry_count_(0u) { | 
|  | CodedOutputStream coded_out(out_); | 
|  |  | 
|  | // Write the magic. | 
|  | coded_out.WriteLittleEndian32(kContainerFormatMagic); | 
|  |  | 
|  | // Write the version. | 
|  | coded_out.WriteLittleEndian32(kContainerFormatVersion); | 
|  |  | 
|  | // Write the total number of entries. | 
|  | coded_out.WriteLittleEndian32(static_cast<uint32_t>(total_entry_count_)); | 
|  |  | 
|  | if (coded_out.HadError()) { | 
|  | error_ = "failed writing container format header"; | 
|  | } | 
|  | } | 
|  |  | 
|  | inline static size_t CalculatePaddingForAlignment(size_t size) { | 
|  | size_t overage = size % kPaddingAlignment; | 
|  | return overage == 0 ? 0 : kPaddingAlignment - overage; | 
|  | } | 
|  |  | 
|  | inline static void WritePadding(size_t padding, CodedOutputStream* out) { | 
|  | CHECK(padding < kPaddingAlignment); | 
|  | const uint32_t zero = 0u; | 
|  | static_assert(sizeof(zero) >= kPaddingAlignment, "Not enough source bytes for padding"); | 
|  |  | 
|  | out->WriteRaw(&zero, padding); | 
|  | } | 
|  |  | 
|  | bool ContainerWriter::AddResTableEntry(const pb::ResourceTable& table) { | 
|  | if (current_entry_count_ >= total_entry_count_) { | 
|  | error_ = "too many entries being serialized"; | 
|  | return false; | 
|  | } | 
|  | current_entry_count_++; | 
|  |  | 
|  | CodedOutputStream coded_out(out_); | 
|  |  | 
|  | // Write the type. | 
|  | coded_out.WriteLittleEndian32(kResTable); | 
|  |  | 
|  | // Write the aligned size. | 
|  | const ::google::protobuf::uint64 size = table.ByteSize(); | 
|  | const int padding = CalculatePaddingForAlignment(size); | 
|  | coded_out.WriteLittleEndian64(size); | 
|  |  | 
|  | // Write the table. | 
|  | table.SerializeWithCachedSizes(&coded_out); | 
|  |  | 
|  | // Write the padding. | 
|  | WritePadding(padding, &coded_out); | 
|  |  | 
|  | if (coded_out.HadError()) { | 
|  | error_ = "failed writing to output"; | 
|  | return false; | 
|  | } | 
|  | return true; | 
|  | } | 
|  |  | 
|  | bool ContainerWriter::AddResFileEntry(const pb::internal::CompiledFile& file, | 
|  | io::KnownSizeInputStream* in) { | 
|  | if (current_entry_count_ >= total_entry_count_) { | 
|  | error_ = "too many entries being serialized"; | 
|  | return false; | 
|  | } | 
|  | current_entry_count_++; | 
|  |  | 
|  | constexpr const static int kResFileEntryHeaderSize = 12; | 
|  |  | 
|  | CodedOutputStream coded_out(out_); | 
|  |  | 
|  | // Write the type. | 
|  | coded_out.WriteLittleEndian32(kResFile); | 
|  |  | 
|  | // Write the aligned size. | 
|  | const ::google::protobuf::uint32 header_size = file.ByteSize(); | 
|  | const int header_padding = CalculatePaddingForAlignment(header_size); | 
|  | const ::google::protobuf::uint64 data_size = in->TotalSize(); | 
|  | const int data_padding = CalculatePaddingForAlignment(data_size); | 
|  | coded_out.WriteLittleEndian64(kResFileEntryHeaderSize + header_size + header_padding + data_size + | 
|  | data_padding); | 
|  |  | 
|  | // Write the res file header size. | 
|  | coded_out.WriteLittleEndian32(header_size); | 
|  |  | 
|  | // Write the data payload size. | 
|  | coded_out.WriteLittleEndian64(data_size); | 
|  |  | 
|  | // Write the header. | 
|  | file.SerializeToCodedStream(&coded_out); | 
|  |  | 
|  | WritePadding(header_padding, &coded_out); | 
|  |  | 
|  | // Write the data payload. We need to call Trim() since we are going to write to the underlying | 
|  | // ZeroCopyOutputStream. | 
|  | coded_out.Trim(); | 
|  |  | 
|  | // Check at this point if there were any errors. | 
|  | if (coded_out.HadError()) { | 
|  | error_ = "failed writing to output"; | 
|  | return false; | 
|  | } | 
|  |  | 
|  | if (!io::Copy(out_, in)) { | 
|  | if (in->HadError()) { | 
|  | std::ostringstream error; | 
|  | error << "failed reading from input: " << in->GetError(); | 
|  | error_ = error.str(); | 
|  | } else { | 
|  | error_ = "failed writing to output"; | 
|  | } | 
|  | return false; | 
|  | } | 
|  | WritePadding(data_padding, &coded_out); | 
|  |  | 
|  | if (coded_out.HadError()) { | 
|  | error_ = "failed writing to output"; | 
|  | return false; | 
|  | } | 
|  | return true; | 
|  | } | 
|  |  | 
|  | bool ContainerWriter::HadError() const { | 
|  | return !error_.empty(); | 
|  | } | 
|  |  | 
|  | std::string ContainerWriter::GetError() const { | 
|  | return error_; | 
|  | } | 
|  |  | 
|  | static bool AlignRead(CodedInputStream* in) { | 
|  | const int padding = 4 - (in->CurrentPosition() % 4); | 
|  | if (padding < 4) { | 
|  | return in->Skip(padding); | 
|  | } | 
|  | return true; | 
|  | } | 
|  |  | 
|  | ContainerReaderEntry::ContainerReaderEntry(ContainerReader* reader) : reader_(reader) { | 
|  | } | 
|  |  | 
|  | ContainerEntryType ContainerReaderEntry::Type() const { | 
|  | return type_; | 
|  | } | 
|  |  | 
|  | bool ContainerReaderEntry::GetResTable(pb::ResourceTable* out_table) { | 
|  | TRACE_CALL(); | 
|  | CHECK(type_ == ContainerEntryType::kResTable) << "reading a kResTable when the type is kResFile"; | 
|  | if (length_ > std::numeric_limits<int>::max()) { | 
|  | reader_->error_ = StringPrintf("entry length %zu is too large", length_); | 
|  | return false; | 
|  | } | 
|  |  | 
|  | CodedInputStream& coded_in = reader_->coded_in_; | 
|  |  | 
|  | const CodedInputStream::Limit limit = coded_in.PushLimit(static_cast<int>(length_)); | 
|  | auto guard = ::android::base::make_scope_guard([&]() { coded_in.PopLimit(limit); }); | 
|  |  | 
|  | if (!out_table->ParseFromCodedStream(&coded_in)) { | 
|  | reader_->error_ = "failed to parse ResourceTable"; | 
|  | return false; | 
|  | } | 
|  | return true; | 
|  | } | 
|  |  | 
|  | bool ContainerReaderEntry::GetResFileOffsets(pb::internal::CompiledFile* out_file, | 
|  | off64_t* out_offset, size_t* out_len) { | 
|  | CHECK(type_ == ContainerEntryType::kResFile) << "reading a kResFile when the type is kResTable"; | 
|  |  | 
|  | CodedInputStream& coded_in = reader_->coded_in_; | 
|  |  | 
|  | // Read the ResFile header. | 
|  | ::google::protobuf::uint32 header_length; | 
|  | if (!coded_in.ReadLittleEndian32(&header_length)) { | 
|  | std::ostringstream error; | 
|  | error << "failed to read header length from input: " << reader_->in_->GetError(); | 
|  | reader_->error_ = error.str(); | 
|  | return false; | 
|  | } | 
|  |  | 
|  | ::google::protobuf::uint64 data_length; | 
|  | if (!coded_in.ReadLittleEndian64(&data_length)) { | 
|  | std::ostringstream error; | 
|  | error << "failed to read data length from input: " << reader_->in_->GetError(); | 
|  | reader_->error_ = error.str(); | 
|  | return false; | 
|  | } | 
|  |  | 
|  | if (header_length > std::numeric_limits<int>::max()) { | 
|  | std::ostringstream error; | 
|  | error << "header length " << header_length << " is too large"; | 
|  | reader_->error_ = error.str(); | 
|  | return false; | 
|  | } | 
|  |  | 
|  | if (data_length > std::numeric_limits<size_t>::max()) { | 
|  | std::ostringstream error; | 
|  | error << "data length " << data_length << " is too large"; | 
|  | reader_->error_ = error.str(); | 
|  | return false; | 
|  | } | 
|  |  | 
|  | { | 
|  | const CodedInputStream::Limit limit = coded_in.PushLimit(static_cast<int>(header_length)); | 
|  | auto guard = ::android::base::make_scope_guard([&]() { coded_in.PopLimit(limit); }); | 
|  |  | 
|  | if (!out_file->ParseFromCodedStream(&coded_in)) { | 
|  | reader_->error_ = "failed to parse CompiledFile header"; | 
|  | return false; | 
|  | } | 
|  | } | 
|  |  | 
|  | AlignRead(&coded_in); | 
|  |  | 
|  | *out_offset = coded_in.CurrentPosition(); | 
|  | *out_len = data_length; | 
|  |  | 
|  | coded_in.Skip(static_cast<int>(data_length)); | 
|  | AlignRead(&coded_in); | 
|  | return true; | 
|  | } | 
|  |  | 
|  | bool ContainerReaderEntry::HadError() const { | 
|  | return reader_->HadError(); | 
|  | } | 
|  |  | 
|  | std::string ContainerReaderEntry::GetError() const { | 
|  | return reader_->GetError(); | 
|  | } | 
|  |  | 
|  | ContainerReader::ContainerReader(io::InputStream* in) | 
|  | : in_(in), | 
|  | adaptor_(in), | 
|  | coded_in_(&adaptor_), | 
|  | total_entry_count_(0u), | 
|  | current_entry_count_(0u), | 
|  | entry_(this) { | 
|  | TRACE_CALL(); | 
|  | ::google::protobuf::uint32 magic; | 
|  | if (!coded_in_.ReadLittleEndian32(&magic)) { | 
|  | std::ostringstream error; | 
|  | error << "failed to read magic from input: " << in_->GetError(); | 
|  | error_ = error.str(); | 
|  | return; | 
|  | } | 
|  |  | 
|  | if (magic != kContainerFormatMagic) { | 
|  | error_ = | 
|  | StringPrintf("magic value is 0x%08x but AAPT expects 0x%08x", magic, kContainerFormatMagic); | 
|  | return; | 
|  | } | 
|  |  | 
|  | ::google::protobuf::uint32 version; | 
|  | if (!coded_in_.ReadLittleEndian32(&version)) { | 
|  | std::ostringstream error; | 
|  | error << "failed to read version from input: " << in_->GetError(); | 
|  | error_ = error.str(); | 
|  | return; | 
|  | } | 
|  |  | 
|  | if (version != kContainerFormatVersion) { | 
|  | error_ = StringPrintf("container version is 0x%08x but AAPT expects version 0x%08x", version, | 
|  | kContainerFormatVersion); | 
|  | return; | 
|  | } | 
|  |  | 
|  | ::google::protobuf::uint32 total_entry_count; | 
|  | if (!coded_in_.ReadLittleEndian32(&total_entry_count)) { | 
|  | std::ostringstream error; | 
|  | error << "failed to read entry count from input: " << in_->GetError(); | 
|  | error_ = error.str(); | 
|  | return; | 
|  | } | 
|  |  | 
|  | total_entry_count_ = total_entry_count; | 
|  | } | 
|  |  | 
|  | ContainerReaderEntry* ContainerReader::Next() { | 
|  | if (current_entry_count_ >= total_entry_count_) { | 
|  | return nullptr; | 
|  | } | 
|  | current_entry_count_++; | 
|  |  | 
|  | // Ensure the next read is aligned. | 
|  | AlignRead(&coded_in_); | 
|  |  | 
|  | ::google::protobuf::uint32 entry_type; | 
|  | if (!coded_in_.ReadLittleEndian32(&entry_type)) { | 
|  | std::ostringstream error; | 
|  | error << "failed reading entry type from input: " << in_->GetError(); | 
|  | error_ = error.str(); | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | ::google::protobuf::uint64 entry_length; | 
|  | if (!coded_in_.ReadLittleEndian64(&entry_length)) { | 
|  | std::ostringstream error; | 
|  | error << "failed reading entry length from input: " << in_->GetError(); | 
|  | error_ = error.str(); | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | if (entry_type == ContainerEntryType::kResFile || entry_type == ContainerEntryType::kResTable) { | 
|  | entry_.type_ = static_cast<ContainerEntryType>(entry_type); | 
|  | } else { | 
|  | error_ = StringPrintf("entry type 0x%08x is invalid", entry_type); | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | if (entry_length > std::numeric_limits<size_t>::max()) { | 
|  | std::ostringstream error; | 
|  | error << "entry length " << entry_length << " is too large"; | 
|  | error_ = error.str(); | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | entry_.length_ = entry_length; | 
|  | return &entry_; | 
|  | } | 
|  |  | 
|  | bool ContainerReader::HadError() const { | 
|  | return !error_.empty(); | 
|  | } | 
|  |  | 
|  | std::string ContainerReader::GetError() const { | 
|  | return error_; | 
|  | } | 
|  |  | 
|  | }  // namespace aapt |