| // |
| // Copyright (C) 2022 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 <array> |
| #include <cstdint> |
| #include <cstdio> |
| #include <iterator> |
| #include <memory> |
| |
| #include <fcntl.h> |
| #include <sys/mman.h> |
| #include <sys/stat.h> |
| |
| #include <android-base/strings.h> |
| #include <base/files/file_path.h> |
| #include <gflags/gflags.h> |
| #include <unistd.h> |
| #include <xz.h> |
| |
| #include "update_engine/common/utils.h" |
| #include "update_engine/common/hash_calculator.h" |
| #include "update_engine/payload_consumer/file_descriptor.h" |
| #include "update_engine/payload_consumer/file_descriptor_utils.h" |
| #include "update_engine/payload_consumer/install_operation_executor.h" |
| #include "update_engine/payload_consumer/payload_metadata.h" |
| #include "update_engine/payload_consumer/verity_writer_android.h" |
| #include "update_engine/update_metadata.pb.h" |
| |
| DEFINE_string(payload, "", "Path to payload.bin"); |
| DEFINE_string( |
| input_dir, |
| "", |
| "Directory to read input images. Only required for incremental OTAs"); |
| DEFINE_string(output_dir, "", "Directory to put output images"); |
| DEFINE_int64(payload_offset, |
| 0, |
| "Offset to start of payload.bin. Useful if payload path actually " |
| "points to a .zip file containing payload.bin"); |
| DEFINE_string(partitions, |
| "", |
| "Comma separated list of partitions to extract, leave empty for " |
| "extracting all partitions"); |
| |
| using chromeos_update_engine::DeltaArchiveManifest; |
| using chromeos_update_engine::PayloadMetadata; |
| |
| namespace chromeos_update_engine { |
| |
| void WriteVerity(const PartitionUpdate& partition, |
| FileDescriptorPtr fd, |
| const size_t block_size) { |
| // 512KB buffer, arbitrary value. Larger buffers may improve performance. |
| static constexpr size_t BUFFER_SIZE = 1024 * 512; |
| if (partition.hash_tree_extent().num_blocks() == 0 && |
| partition.fec_extent().num_blocks() == 0) { |
| return; |
| } |
| InstallPlan::Partition install_part; |
| install_part.block_size = block_size; |
| CHECK(install_part.ParseVerityConfig(partition)); |
| VerityWriterAndroid writer; |
| CHECK(writer.Init(install_part)); |
| std::array<uint8_t, BUFFER_SIZE> buffer; |
| const auto data_size = |
| install_part.hash_tree_data_offset + install_part.hash_tree_data_size; |
| size_t offset = 0; |
| while (offset < data_size) { |
| const auto bytes_to_read = |
| static_cast<ssize_t>(std::min(BUFFER_SIZE, data_size - offset)); |
| ssize_t bytes_read; |
| CHECK( |
| utils::ReadAll(fd, buffer.data(), bytes_to_read, offset, &bytes_read)); |
| CHECK_EQ(bytes_read, bytes_to_read) |
| << " Failed to read at offset " << offset << " " |
| << android::base::ErrnoNumberAsString(errno); |
| writer.Update(offset, buffer.data(), bytes_read); |
| offset += bytes_read; |
| } |
| CHECK(writer.Finalize(fd.get(), fd.get())); |
| return; |
| } |
| |
| bool ExtractImagesFromOTA(const DeltaArchiveManifest& manifest, |
| const PayloadMetadata& metadata, |
| int payload_fd, |
| size_t payload_offset, |
| std::string_view input_dir, |
| std::string_view output_dir, |
| const std::set<std::string>& partitions) { |
| InstallOperationExecutor executor(manifest.block_size()); |
| const size_t data_begin = metadata.GetMetadataSize() + |
| metadata.GetMetadataSignatureSize() + |
| payload_offset; |
| const base::FilePath output_dir_path( |
| base::StringPiece(output_dir.data(), output_dir.size())); |
| const base::FilePath input_dir_path( |
| base::StringPiece(input_dir.data(), input_dir.size())); |
| std::vector<unsigned char> blob; |
| for (const auto& partition : manifest.partitions()) { |
| if (!partitions.empty() && |
| partitions.count(partition.partition_name()) == 0) { |
| continue; |
| } |
| LOG(INFO) << "Extracting partition " << partition.partition_name() |
| << " size: " << partition.new_partition_info().size(); |
| const auto output_path = |
| output_dir_path.Append(partition.partition_name() + ".img").value(); |
| auto out_fd = |
| std::make_shared<chromeos_update_engine::EintrSafeFileDescriptor>(); |
| TEST_AND_RETURN_FALSE_ERRNO( |
| out_fd->Open(output_path.c_str(), O_RDWR | O_CREAT, 0644)); |
| auto in_fd = |
| std::make_shared<chromeos_update_engine::EintrSafeFileDescriptor>(); |
| if (partition.has_old_partition_info()) { |
| const auto input_path = |
| input_dir_path.Append(partition.partition_name() + ".img").value(); |
| LOG(INFO) << "Incremental OTA detected for partition " |
| << partition.partition_name() << " opening source image " |
| << input_path; |
| CHECK(in_fd->Open(input_path.c_str(), O_RDONLY)) |
| << " failed to open " << input_path; |
| } |
| |
| for (const auto& op : partition.operations()) { |
| if (op.has_src_sha256_hash()) { |
| brillo::Blob actual_hash; |
| TEST_AND_RETURN_FALSE(fd_utils::ReadAndHashExtents( |
| in_fd, op.src_extents(), manifest.block_size(), &actual_hash)); |
| CHECK_EQ(HexEncode(ToStringView(actual_hash)), |
| HexEncode(op.src_sha256_hash())); |
| } |
| |
| blob.resize(op.data_length()); |
| const auto op_data_offset = data_begin + op.data_offset(); |
| ssize_t bytes_read = 0; |
| TEST_AND_RETURN_FALSE(utils::PReadAll( |
| payload_fd, blob.data(), blob.size(), op_data_offset, &bytes_read)); |
| if (op.has_data_sha256_hash()) { |
| brillo::Blob actual_hash; |
| TEST_AND_RETURN_FALSE( |
| HashCalculator::RawHashOfData(blob, &actual_hash)); |
| CHECK_EQ(HexEncode(ToStringView(actual_hash)), |
| HexEncode(op.data_sha256_hash())); |
| } |
| auto direct_writer = std::make_unique<DirectExtentWriter>(out_fd); |
| if (op.type() == InstallOperation::ZERO) { |
| TEST_AND_RETURN_FALSE(executor.ExecuteZeroOrDiscardOperation( |
| op, std::move(direct_writer))); |
| } else if (op.type() == InstallOperation::REPLACE || |
| op.type() == InstallOperation::REPLACE_BZ || |
| op.type() == InstallOperation::REPLACE_XZ) { |
| TEST_AND_RETURN_FALSE(executor.ExecuteReplaceOperation( |
| op, std::move(direct_writer), blob.data(), blob.size())); |
| } else if (op.type() == InstallOperation::SOURCE_COPY) { |
| CHECK(in_fd->IsOpen()); |
| TEST_AND_RETURN_FALSE(executor.ExecuteSourceCopyOperation( |
| op, std::move(direct_writer), in_fd)); |
| } else { |
| CHECK(in_fd->IsOpen()); |
| TEST_AND_RETURN_FALSE(executor.ExecuteDiffOperation( |
| op, std::move(direct_writer), in_fd, blob.data(), blob.size())); |
| } |
| } |
| WriteVerity(partition, out_fd, manifest.block_size()); |
| int err = |
| truncate64(output_path.c_str(), partition.new_partition_info().size()); |
| if (err) { |
| PLOG(ERROR) << "Failed to truncate " << output_path << " to " |
| << partition.new_partition_info().size(); |
| } |
| brillo::Blob actual_hash; |
| TEST_AND_RETURN_FALSE( |
| HashCalculator::RawHashOfFile(output_path, &actual_hash)); |
| CHECK_EQ(HexEncode(ToStringView(actual_hash)), |
| HexEncode(partition.new_partition_info().hash())) |
| << " Partition " << partition.partition_name() |
| << " hash mismatches. Either the source image or OTA package is " |
| "corrupted."; |
| } |
| return true; |
| } |
| |
| } // namespace chromeos_update_engine |
| |
| namespace { |
| |
| bool IsIncrementalOTA(const DeltaArchiveManifest& manifest) { |
| for (const auto& part : manifest.partitions()) { |
| if (part.has_old_partition_info()) { |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| } // namespace |
| |
| int main(int argc, char* argv[]) { |
| gflags::SetUsageMessage( |
| "A tool to extract device images from Android OTA packages"); |
| gflags::ParseCommandLineFlags(&argc, &argv, true); |
| xz_crc32_init(); |
| auto tokens = android::base::Tokenize(FLAGS_partitions, ","); |
| const std::set<std::string> partitions( |
| std::make_move_iterator(tokens.begin()), |
| std::make_move_iterator(tokens.end())); |
| if (FLAGS_payload.empty()) { |
| LOG(ERROR) << "--payload <payload path> is required"; |
| return 1; |
| } |
| if (!partitions.empty()) { |
| LOG(INFO) << "Extracting " << android::base::Join(partitions, ", "); |
| } |
| int payload_fd = open(FLAGS_payload.c_str(), O_RDONLY | O_CLOEXEC); |
| if (payload_fd < 0) { |
| PLOG(ERROR) << "Failed to open payload file"; |
| return 1; |
| } |
| chromeos_update_engine::ScopedFdCloser closer{&payload_fd}; |
| auto payload_size = chromeos_update_engine::utils::FileSize(payload_fd); |
| if (payload_size <= 0) { |
| PLOG(ERROR) |
| << "Couldn't determine size of payload file, or payload file is empty"; |
| return 1; |
| } |
| |
| PayloadMetadata payload_metadata; |
| auto payload = static_cast<unsigned char*>( |
| mmap(nullptr, payload_size, PROT_READ, MAP_PRIVATE, payload_fd, 0)); |
| |
| if (payload == MAP_FAILED) { |
| PLOG(ERROR) << "Failed to mmap() payload file"; |
| return 1; |
| } |
| |
| auto munmap_deleter = [payload_size](auto payload) { |
| munmap(payload, payload_size); |
| }; |
| std::unique_ptr<unsigned char, decltype(munmap_deleter)> munmapper{ |
| payload, munmap_deleter}; |
| if (payload_metadata.ParsePayloadHeader(payload + FLAGS_payload_offset, |
| payload_size - FLAGS_payload_offset, |
| nullptr) != |
| chromeos_update_engine::MetadataParseResult::kSuccess) { |
| LOG(ERROR) << "Payload header parse failed!"; |
| return 1; |
| } |
| DeltaArchiveManifest manifest; |
| if (!payload_metadata.GetManifest(payload + FLAGS_payload_offset, |
| payload_size - FLAGS_payload_offset, |
| &manifest)) { |
| LOG(ERROR) << "Failed to parse manifest!"; |
| return 1; |
| } |
| if (IsIncrementalOTA(manifest) && FLAGS_input_dir.empty()) { |
| LOG(ERROR) << FLAGS_payload |
| << " is an incremental OTA, --input_dir parameter is required."; |
| return 1; |
| } |
| return !ExtractImagesFromOTA(manifest, |
| payload_metadata, |
| payload_fd, |
| FLAGS_payload_offset, |
| FLAGS_input_dir, |
| FLAGS_output_dir, |
| partitions); |
| } |