microdroid/payload/mk_payload.cc - platform/packages/modules/Virtualization - Git at Google

 /*
  * Copyright (C) 2021 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 <sys/stat.h>
 #include <sys/types.h>
 #include <unistd.h>

 #include <fstream>
 #include <iostream>
 #include <optional>
 #include <string>
 #include <vector>

 #include <android-base/file.h>
 #include <android-base/result.h>
 #include <image_aggregator.h>
 #include <json/json.h>

 #include "microdroid/metadata.h"

 using android::base::Dirname;
 using android::base::ErrnoError;
 using android::base::Error;
 using android::base::Result;
 using android::base::unique_fd;
 using android::microdroid::ApexPayload;
 using android::microdroid::ApkPayload;
 using android::microdroid::Metadata;
 using android::microdroid::WriteMetadata;

 using cuttlefish::AlignToPartitionSize;
 using cuttlefish::CreateCompositeDisk;
 using cuttlefish::kLinuxFilesystem;
 using cuttlefish::MultipleImagePartition;

 Result<uint32_t> GetFileSize(const std::string& path) {
     struct stat st;
     if (lstat(path.c_str(), &st) == -1) {
         return ErrnoError() << "Can't lstat " << path;
     }
     return static_cast<uint32_t>(st.st_size);
 }

 std::string RelativeTo(const std::string& path, const std::string& dirname) {
     bool is_absolute = !path.empty() && path[0] == '/';
     if (is_absolute || dirname == ".") {
         return path;
     } else {
         return dirname + "/" + path;
     }
 }

 // Returns `append` is appended to the end of filename preserving the extension.
 std::string AppendFileName(const std::string& filename, const std::string& append) {
     size_t pos = filename.find_last_of('.');
     if (pos == std::string::npos) {
         return filename + append;
     } else {
         return filename.substr(0, pos) + append + filename.substr(pos);
     }
 }

 struct ApexConfig {
     std::string name; // the apex name
     std::string path; // the path to the apex file
                       // absolute or relative to the config file
 };

 struct ApkConfig {
     std::string name;
     std::string path;
     std::string idsig_path;
 };

 struct Config {
     std::string dirname; // config file's direname to resolve relative paths in the config

     std::vector<ApexConfig> apexes;
     std::optional<ApkConfig> apk;
     // This is a path in the guest side
     std::optional<std::string> payload_config_path;
 };

 #define DO(expr) \
     if (auto res = (expr); !res.ok()) return res.error()

 Result<void> ParseJson(const Json::Value& value, std::string& s) {
     if (!value.isString()) {
         return Error() << "should be a string: " << value;
     }
     s = value.asString();
     return {};
 }

 template <typename T>
 Result<void> ParseJson(const Json::Value& value, std::optional<T>& s) {
     if (value.isNull()) {
         s.reset();
         return {};
     }
     s.emplace();
     return ParseJson(value, *s);
 }

 template <typename T>
 Result<void> ParseJson(const Json::Value& values, std::vector<T>& parsed) {
     for (const Json::Value& value : values) {
         T t;
         DO(ParseJson(value, t));
         parsed.push_back(std::move(t));
     }
     return {};
 }

 Result<void> ParseJson(const Json::Value& value, ApexConfig& apex_config) {
     DO(ParseJson(value["name"], apex_config.name));
     DO(ParseJson(value["path"], apex_config.path));
     return {};
 }

 Result<void> ParseJson(const Json::Value& value, ApkConfig& apk_config) {
     DO(ParseJson(value["name"], apk_config.name));
     DO(ParseJson(value["path"], apk_config.path));
     DO(ParseJson(value["idsig_path"], apk_config.idsig_path));
     return {};
 }

 Result<void> ParseJson(const Json::Value& value, Config& config) {
     DO(ParseJson(value["apexes"], config.apexes));
     DO(ParseJson(value["apk"], config.apk));
     DO(ParseJson(value["payload_config_path"], config.payload_config_path));
     return {};
 }

 Result<Config> LoadConfig(const std::string& config_file) {
     std::ifstream in(config_file);
     Json::CharReaderBuilder builder;
     Json::Value root;
     Json::String errs;
     if (!parseFromStream(builder, in, &root, &errs)) {
         return Error() << errs;
     }

     Config config;
     config.dirname = Dirname(config_file);
     DO(ParseJson(root, config));
     return config;
 }

 #undef DO

 Result<void> MakeMetadata(const Config& config, const std::string& filename) {
     Metadata metadata;
     metadata.set_version(1);

     for (const auto& apex_config : config.apexes) {
         auto* apex = metadata.add_apexes();
         apex->set_name(apex_config.name);
         apex->set_partition_name(apex_config.name);
         apex->set_is_factory(true);
     }

     if (config.apk.has_value()) {
         auto* apk = metadata.mutable_apk();
         apk->set_name(config.apk->name);
         apk->set_payload_partition_name("microdroid-apk");
         apk->set_idsig_partition_name("microdroid-apk-idsig");
     }

     if (config.payload_config_path.has_value()) {
         *metadata.mutable_payload_config_path() = config.payload_config_path.value();
     }

     std::ofstream out(filename);
     return WriteMetadata(metadata, out);
 }

 // fill zeros to align |file_path|'s size to BLOCK_SIZE(4096) boundary.
 // return true when the filler is needed.
 Result<bool> ZeroFiller(const std::string& file_path, const std::string& filler_path) {
     auto file_size = GetFileSize(file_path);
     if (!file_size.ok()) {
         return file_size.error();
     }
     auto disk_size = AlignToPartitionSize(*file_size);
     if (disk_size <= *file_size) {
         return false;
     }
     unique_fd fd(TEMP_FAILURE_RETRY(open(filler_path.c_str(), O_CREAT | O_WRONLY | O_TRUNC, 0600)));
     if (fd.get() == -1) {
         return ErrnoError() << "open(" << filler_path << ") failed.";
     }
     if (ftruncate(fd.get(), disk_size - *file_size) == -1) {
         return ErrnoError() << "ftruncate(" << filler_path << ") failed.";
     }
     return true;
 }

 Result<void> MakePayload(const Config& config, const std::string& metadata_file,
                          const std::string& output_file) {
     std::vector<MultipleImagePartition> partitions;

     int filler_count = 0;
     auto add_partition = [&](auto partition_name, auto file_path) -> Result<void> {
         std::vector<std::string> image_files{file_path};

         std::string filler_path =
                 AppendFileName(output_file, "-filler-" + std::to_string(filler_count++));
         if (auto ret = ZeroFiller(file_path, filler_path); !ret.ok()) {
             return ret.error();
         } else if (*ret) {
             image_files.push_back(filler_path);
         }
         partitions.push_back(MultipleImagePartition{
                 .label = partition_name,
                 .image_file_paths = image_files,
                 .type = kLinuxFilesystem,
                 .read_only = true,
         });
         return {};
     };

     // put metadata at the first partition
     partitions.push_back(MultipleImagePartition{
             .label = "payload-metadata",
             .image_file_paths = {metadata_file},
             .type = kLinuxFilesystem,
             .read_only = true,
     });
     // put apexes at the subsequent partitions
     for (size_t i = 0; i < config.apexes.size(); i++) {
         const auto& apex_config = config.apexes[i];
         std::string apex_path = RelativeTo(apex_config.path, config.dirname);
         if (auto ret = add_partition("microdroid-apex-" + std::to_string(i), apex_path);
             !ret.ok()) {
             return ret.error();
         }
     }
     // put apk and its idsig
     if (config.apk.has_value()) {
         std::string apk_path = RelativeTo(config.apk->path, config.dirname);
         if (auto ret = add_partition("microdroid-apk", apk_path); !ret.ok()) {
             return ret.error();
         }
         std::string idsig_path = RelativeTo(config.apk->idsig_path, config.dirname);
         if (auto ret = add_partition("microdroid-apk-idsig", idsig_path); !ret.ok()) {
             return ret.error();
         }
     }

     const std::string gpt_header = AppendFileName(output_file, "-header");
     const std::string gpt_footer = AppendFileName(output_file, "-footer");
     CreateCompositeDisk(partitions, gpt_header, gpt_footer, output_file);
     return {};
 }

 int main(int argc, char** argv) {
     if (argc < 3 || argc > 4) {
         std::cerr << "Usage: " << argv[0] << " [--metadata-only] <config> <output>\n";
         return 1;
     }
     int arg_index = 1;
     bool metadata_only = false;
     if (strcmp(argv[arg_index], "--metadata-only") == 0) {
         metadata_only = true;
         arg_index++;
     }

     auto config = LoadConfig(argv[arg_index++]);
     if (!config.ok()) {
         std::cerr << "bad config: " << config.error() << '\n';
         return 1;
     }

     const std::string output_file(argv[arg_index++]);
     const std::string metadata_file =
             metadata_only ? output_file : AppendFileName(output_file, "-metadata");

     if (const auto res = MakeMetadata(*config, metadata_file); !res.ok()) {
         std::cerr << res.error() << '\n';
         return 1;
     }
     if (metadata_only) {
         return 0;
     }
     if (const auto res = MakePayload(*config, metadata_file, output_file); !res.ok()) {
         std::cerr << res.error() << '\n';
         return 1;
     }

     return 0;
 }
	/*
	* Copyright (C) 2021 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 <sys/stat.h>
	#include <sys/types.h>
	#include <unistd.h>

	#include <fstream>
	#include <iostream>
	#include <optional>
	#include <string>
	#include <vector>

	#include <android-base/file.h>
	#include <android-base/result.h>
	#include <image_aggregator.h>
	#include <json/json.h>

	#include "microdroid/metadata.h"

	using android::base::Dirname;
	using android::base::ErrnoError;
	using android::base::Error;
	using android::base::Result;
	using android::base::unique_fd;
	using android::microdroid::ApexPayload;
	using android::microdroid::ApkPayload;
	using android::microdroid::Metadata;
	using android::microdroid::WriteMetadata;

	using cuttlefish::AlignToPartitionSize;
	using cuttlefish::CreateCompositeDisk;
	using cuttlefish::kLinuxFilesystem;
	using cuttlefish::MultipleImagePartition;

	Result<uint32_t> GetFileSize(const std::string& path) {
	struct stat st;
	if (lstat(path.c_str(), &st) == -1) {
	return ErrnoError() << "Can't lstat " << path;
	}
	return static_cast<uint32_t>(st.st_size);
	}

	std::string RelativeTo(const std::string& path, const std::string& dirname) {
	bool is_absolute = !path.empty() && path[0] == '/';
	if (is_absolute \|\| dirname == ".") {
	return path;
	} else {
	return dirname + "/" + path;
	}
	}

	// Returns `append` is appended to the end of filename preserving the extension.
	std::string AppendFileName(const std::string& filename, const std::string& append) {
	size_t pos = filename.find_last_of('.');
	if (pos == std::string::npos) {
	return filename + append;
	} else {
	return filename.substr(0, pos) + append + filename.substr(pos);
	}
	}

	struct ApexConfig {
	std::string name; // the apex name
	std::string path; // the path to the apex file
	// absolute or relative to the config file
	};

	struct ApkConfig {
	std::string name;
	std::string path;
	std::string idsig_path;
	};

	struct Config {
	std::string dirname; // config file's direname to resolve relative paths in the config

	std::vector<ApexConfig> apexes;
	std::optional<ApkConfig> apk;
	// This is a path in the guest side
	std::optional<std::string> payload_config_path;
	};

	#define DO(expr) \
	if (auto res = (expr); !res.ok()) return res.error()

	Result<void> ParseJson(const Json::Value& value, std::string& s) {
	if (!value.isString()) {
	return Error() << "should be a string: " << value;
	}
	s = value.asString();
	return {};
	}

	template <typename T>
	Result<void> ParseJson(const Json::Value& value, std::optional<T>& s) {
	if (value.isNull()) {
	s.reset();
	return {};
	}
	s.emplace();
	return ParseJson(value, *s);
	}

	template <typename T>
	Result<void> ParseJson(const Json::Value& values, std::vector<T>& parsed) {
	for (const Json::Value& value : values) {
	T t;
	DO(ParseJson(value, t));
	parsed.push_back(std::move(t));
	}
	return {};
	}

	Result<void> ParseJson(const Json::Value& value, ApexConfig& apex_config) {
	DO(ParseJson(value["name"], apex_config.name));
	DO(ParseJson(value["path"], apex_config.path));
	return {};
	}

	Result<void> ParseJson(const Json::Value& value, ApkConfig& apk_config) {
	DO(ParseJson(value["name"], apk_config.name));
	DO(ParseJson(value["path"], apk_config.path));
	DO(ParseJson(value["idsig_path"], apk_config.idsig_path));
	return {};
	}

	Result<void> ParseJson(const Json::Value& value, Config& config) {
	DO(ParseJson(value["apexes"], config.apexes));
	DO(ParseJson(value["apk"], config.apk));
	DO(ParseJson(value["payload_config_path"], config.payload_config_path));
	return {};
	}

	Result<Config> LoadConfig(const std::string& config_file) {
	std::ifstream in(config_file);
	Json::CharReaderBuilder builder;
	Json::Value root;
	Json::String errs;
	if (!parseFromStream(builder, in, &root, &errs)) {
	return Error() << errs;
	}

	Config config;
	config.dirname = Dirname(config_file);
	DO(ParseJson(root, config));
	return config;
	}

	#undef DO

	Result<void> MakeMetadata(const Config& config, const std::string& filename) {
	Metadata metadata;
	metadata.set_version(1);

	for (const auto& apex_config : config.apexes) {
	auto* apex = metadata.add_apexes();
	apex->set_name(apex_config.name);
	apex->set_partition_name(apex_config.name);
	apex->set_is_factory(true);
	}

	if (config.apk.has_value()) {
	auto* apk = metadata.mutable_apk();
	apk->set_name(config.apk->name);
	apk->set_payload_partition_name("microdroid-apk");
	apk->set_idsig_partition_name("microdroid-apk-idsig");
	}

	if (config.payload_config_path.has_value()) {
	*metadata.mutable_payload_config_path() = config.payload_config_path.value();
	}

	std::ofstream out(filename);
	return WriteMetadata(metadata, out);
	}

	// fill zeros to align \|file_path\|'s size to BLOCK_SIZE(4096) boundary.
	// return true when the filler is needed.
	Result<bool> ZeroFiller(const std::string& file_path, const std::string& filler_path) {
	auto file_size = GetFileSize(file_path);
	if (!file_size.ok()) {
	return file_size.error();
	}
	auto disk_size = AlignToPartitionSize(*file_size);
	if (disk_size <= *file_size) {
	return false;
	}
	unique_fd fd(TEMP_FAILURE_RETRY(open(filler_path.c_str(), O_CREAT \| O_WRONLY \| O_TRUNC, 0600)));
	if (fd.get() == -1) {
	return ErrnoError() << "open(" << filler_path << ") failed.";
	}
	if (ftruncate(fd.get(), disk_size - *file_size) == -1) {
	return ErrnoError() << "ftruncate(" << filler_path << ") failed.";
	}
	return true;
	}

	Result<void> MakePayload(const Config& config, const std::string& metadata_file,
	const std::string& output_file) {
	std::vector<MultipleImagePartition> partitions;

	int filler_count = 0;
	auto add_partition = [&](auto partition_name, auto file_path) -> Result<void> {
	std::vector<std::string> image_files{file_path};

	std::string filler_path =
	AppendFileName(output_file, "-filler-" + std::to_string(filler_count++));
	if (auto ret = ZeroFiller(file_path, filler_path); !ret.ok()) {
	return ret.error();
	} else if (*ret) {
	image_files.push_back(filler_path);
	}
	partitions.push_back(MultipleImagePartition{
	.label = partition_name,
	.image_file_paths = image_files,
	.type = kLinuxFilesystem,
	.read_only = true,
	});
	return {};
	};

	// put metadata at the first partition
	partitions.push_back(MultipleImagePartition{
	.label = "payload-metadata",
	.image_file_paths = {metadata_file},
	.type = kLinuxFilesystem,
	.read_only = true,
	});
	// put apexes at the subsequent partitions
	for (size_t i = 0; i < config.apexes.size(); i++) {
	const auto& apex_config = config.apexes[i];
	std::string apex_path = RelativeTo(apex_config.path, config.dirname);
	if (auto ret = add_partition("microdroid-apex-" + std::to_string(i), apex_path);
	!ret.ok()) {
	return ret.error();
	}
	}
	// put apk and its idsig
	if (config.apk.has_value()) {
	std::string apk_path = RelativeTo(config.apk->path, config.dirname);
	if (auto ret = add_partition("microdroid-apk", apk_path); !ret.ok()) {
	return ret.error();
	}
	std::string idsig_path = RelativeTo(config.apk->idsig_path, config.dirname);
	if (auto ret = add_partition("microdroid-apk-idsig", idsig_path); !ret.ok()) {
	return ret.error();
	}
	}

	const std::string gpt_header = AppendFileName(output_file, "-header");
	const std::string gpt_footer = AppendFileName(output_file, "-footer");
	CreateCompositeDisk(partitions, gpt_header, gpt_footer, output_file);
	return {};
	}

	int main(int argc, char** argv) {
	if (argc < 3 \|\| argc > 4) {
	std::cerr << "Usage: " << argv[0] << " [--metadata-only] <config> <output>\n";
	return 1;
	}
	int arg_index = 1;
	bool metadata_only = false;
	if (strcmp(argv[arg_index], "--metadata-only") == 0) {
	metadata_only = true;
	arg_index++;
	}

	auto config = LoadConfig(argv[arg_index++]);
	if (!config.ok()) {
	std::cerr << "bad config: " << config.error() << '\n';
	return 1;
	}

	const std::string output_file(argv[arg_index++]);
	const std::string metadata_file =
	metadata_only ? output_file : AppendFileName(output_file, "-metadata");

	if (const auto res = MakeMetadata(*config, metadata_file); !res.ok()) {
	std::cerr << res.error() << '\n';
	return 1;
	}
	if (metadata_only) {
	return 0;
	}
	if (const auto res = MakePayload(*config, metadata_file, output_file); !res.ok()) {
	std::cerr << res.error() << '\n';
	return 1;
	}

	return 0;
	}