| /* | 
 |  * 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 size_t size = table.ByteSizeLong(); | 
 |   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 size_t header_size = file.ByteSizeLong(); | 
 |   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 |