libnativeloader/public_libraries.cpp - platform/system/core - Git at Google

 /*
  * Copyright (C) 2019 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.
  */

 #define LOG_TAG "nativeloader"

 #include "public_libraries.h"

 #include <dirent.h>

 #include <algorithm>
 #include <memory>

 #include <android-base/file.h>
 #include <android-base/logging.h>
 #include <android-base/properties.h>
 #include <android-base/strings.h>
 #include <log/log.h>

 #include "utils.h"

 namespace android::nativeloader {

 using namespace std::string_literals;

 namespace {

 constexpr const char* kDefaultPublicLibrariesFile = "/etc/public.libraries.txt";
 constexpr const char* kExtendedPublicLibrariesFilePrefix = "public.libraries-";
 constexpr const char* kExtendedPublicLibrariesFileSuffix = ".txt";
 constexpr const char* kVendorPublicLibrariesFile = "/vendor/etc/public.libraries.txt";
 constexpr const char* kLlndkLibrariesFile = "/system/etc/llndk.libraries.txt";
 constexpr const char* kVndkLibrariesFile = "/system/etc/vndksp.libraries.txt";

 const std::vector<const std::string> kRuntimePublicLibraries = {
     "libicuuc.so",
     "libicui18n.so",
 };

 constexpr const char* kRuntimeApexLibPath = "/apex/com.android.runtime/" LIB;

 // TODO(b/130388701): do we need this?
 std::string root_dir() {
   static const char* android_root_env = getenv("ANDROID_ROOT");
   return android_root_env != nullptr ? android_root_env : "/system";
 }

 bool debuggable() {
   static bool debuggable = android::base::GetBoolProperty("ro.debuggable", false);
   return debuggable;
 }

 std::string vndk_version_str() {
   static std::string version = android::base::GetProperty("ro.vndk.version", "");
   if (version != "" && version != "current") {
     return "." + version;
   }
   return "";
 }

 // For debuggable platform builds use ANDROID_ADDITIONAL_PUBLIC_LIBRARIES environment
 // variable to add libraries to the list. This is intended for platform tests only.
 std::string additional_public_libraries() {
   if (debuggable()) {
     const char* val = getenv("ANDROID_ADDITIONAL_PUBLIC_LIBRARIES");
     return val ? val : "";
   }
   return "";
 }

 void InsertVndkVersionStr(std::string* file_name) {
   CHECK(file_name != nullptr);
   size_t insert_pos = file_name->find_last_of(".");
   if (insert_pos == std::string::npos) {
     insert_pos = file_name->length();
   }
   file_name->insert(insert_pos, vndk_version_str());
 }

 const std::function<bool(const std::string&, std::string*)> always_true =
     [](const std::string&, std::string*) { return true; };

 bool ReadConfig(const std::string& configFile, std::vector<std::string>* sonames,
                 const std::function<bool(const std::string& /* soname */,
                                          std::string* /* error_msg */)>& check_soname,
                 std::string* error_msg = nullptr) {
   // Read list of public native libraries from the config file.
   std::string file_content;
   if (!base::ReadFileToString(configFile, &file_content)) {
     if (error_msg) *error_msg = strerror(errno);
     return false;
   }

   std::vector<std::string> lines = base::Split(file_content, "\n");

   for (auto& line : lines) {
     auto trimmed_line = base::Trim(line);
     if (trimmed_line[0] == '#' || trimmed_line.empty()) {
       continue;
     }
     size_t space_pos = trimmed_line.rfind(' ');
     if (space_pos != std::string::npos) {
       std::string type = trimmed_line.substr(space_pos + 1);
       if (type != "32" && type != "64") {
         if (error_msg) *error_msg = "Malformed line: " + line;
         return false;
       }
 #if defined(__LP64__)
       // Skip 32 bit public library.
       if (type == "32") {
         continue;
       }
 #else
       // Skip 64 bit public library.
       if (type == "64") {
         continue;
       }
 #endif
       trimmed_line.resize(space_pos);
     }

     if (check_soname(trimmed_line, error_msg)) {
       sonames->push_back(trimmed_line);
     } else {
       return false;
     }
   }
   return true;
 }

 void ReadExtensionLibraries(const char* dirname, std::vector<std::string>* sonames) {
   std::unique_ptr<DIR, decltype(&closedir)> dir(opendir(dirname), closedir);
   if (dir != nullptr) {
     // Failing to opening the dir is not an error, which can happen in
     // webview_zygote.
     while (struct dirent* ent = readdir(dir.get())) {
       if (ent->d_type != DT_REG && ent->d_type != DT_LNK) {
         continue;
       }
       const std::string filename(ent->d_name);
       std::string_view fn = filename;
       if (android::base::ConsumePrefix(&fn, kExtendedPublicLibrariesFilePrefix) &&
           android::base::ConsumeSuffix(&fn, kExtendedPublicLibrariesFileSuffix)) {
         const std::string company_name(fn);
         const std::string config_file_path = dirname + "/"s + filename;
         LOG_ALWAYS_FATAL_IF(
             company_name.empty(),
             "Error extracting company name from public native library list file path \"%s\"",
             config_file_path.c_str());

         std::string error_msg;

         LOG_ALWAYS_FATAL_IF(
             !ReadConfig(config_file_path, sonames,
                         [&company_name](const std::string& soname, std::string* error_msg) {
                           if (android::base::StartsWith(soname, "lib") &&
                               android::base::EndsWith(soname, "." + company_name + ".so")) {
                             return true;
                           } else {
                             *error_msg = "Library name \"" + soname +
                                          "\" does not end with the company name: " + company_name +
                                          ".";
                             return false;
                           }
                         },
                         &error_msg),
             "Error reading public native library list from \"%s\": %s", config_file_path.c_str(),
             error_msg.c_str());
       }
     }
   }
 }

 static std::string InitDefaultPublicLibraries() {
   std::string config_file = root_dir() + kDefaultPublicLibrariesFile;
   std::vector<std::string> sonames;
   std::string error_msg;
   LOG_ALWAYS_FATAL_IF(!ReadConfig(config_file, &sonames, always_true, &error_msg),
                       "Error reading public native library list from \"%s\": %s",
                       config_file.c_str(), error_msg.c_str());

   std::string additional_libs = additional_public_libraries();
   if (!additional_libs.empty()) {
     auto vec = base::Split(additional_libs, ":");
     std::copy(vec.begin(), vec.end(), std::back_inserter(sonames));
   }

   // Remove the public libs in the runtime namespace.
   // These libs are listed in public.android.txt, but we don't want the rest of android
   // in default namespace to dlopen the libs.
   // For example, libicuuc.so is exposed to classloader namespace from runtime namespace.
   // Unfortunately, it does not have stable C symbols, and default namespace should only use
   // stable symbols in libandroidicu.so. http://b/120786417
   for (const std::string& lib_name : kRuntimePublicLibraries) {
     std::string path(kRuntimeApexLibPath);
     path.append("/").append(lib_name);

     struct stat s;
     // Do nothing if the path in /apex does not exist.
     // Runtime APEX must be mounted since libnativeloader is in the same APEX
     if (stat(path.c_str(), &s) != 0) {
       continue;
     }

     auto it = std::find(sonames.begin(), sonames.end(), lib_name);
     if (it != sonames.end()) {
       sonames.erase(it);
     }
   }
   return android::base::Join(sonames, ':');
 }

 static std::string InitRuntimePublicLibraries() {
   CHECK(sizeof(kRuntimePublicLibraries) > 0);
   std::string list = android::base::Join(kRuntimePublicLibraries, ":");

   std::string additional_libs = additional_public_libraries();
   if (!additional_libs.empty()) {
     list = list + ':' + additional_libs;
   }
   return list;
 }

 static std::string InitVendorPublicLibraries() {
   // This file is optional, quietly ignore if the file does not exist.
   std::vector<std::string> sonames;
   ReadConfig(kVendorPublicLibrariesFile, &sonames, always_true, nullptr);
   return android::base::Join(sonames, ':');
 }

 // read /system/etc/public.libraries-<companyname>.txt and
 // /product/etc/public.libraries-<companyname>.txt which contain partner defined
 // system libs that are exposed to apps. The libs in the txt files must be
 // named as lib<name>.<companyname>.so.
 static std::string InitExtendedPublicLibraries() {
   std::vector<std::string> sonames;
   ReadExtensionLibraries("/system/etc", &sonames);
   ReadExtensionLibraries("/product/etc", &sonames);
   return android::base::Join(sonames, ':');
 }

 static std::string InitLlndkLibraries() {
   std::string config_file = kLlndkLibrariesFile;
   InsertVndkVersionStr(&config_file);
   std::vector<std::string> sonames;
   ReadConfig(config_file, &sonames, always_true, nullptr);
   return android::base::Join(sonames, ':');
 }

 static std::string InitVndkspLibraries() {
   std::string config_file = kVndkLibrariesFile;
   InsertVndkVersionStr(&config_file);
   std::vector<std::string> sonames;
   ReadConfig(config_file, &sonames, always_true, nullptr);
   return android::base::Join(sonames, ':');
 }

 }  // namespace

 const std::string& default_public_libraries() {
   static std::string list = InitDefaultPublicLibraries();
   return list;
 }

 const std::string& runtime_public_libraries() {
   static std::string list = InitRuntimePublicLibraries();
   return list;
 }

 const std::string& vendor_public_libraries() {
   static std::string list = InitVendorPublicLibraries();
   return list;
 }

 const std::string& extended_public_libraries() {
   static std::string list = InitExtendedPublicLibraries();
   return list;
 }

 const std::string& llndk_libraries() {
   static std::string list = InitLlndkLibraries();
   return list;
 }

 const std::string& vndksp_libraries() {
   static std::string list = InitVndkspLibraries();
   return list;
 }

 }  // namespace android::nativeloader
	/*
	* Copyright (C) 2019 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.
	*/

	#define LOG_TAG "nativeloader"

	#include "public_libraries.h"

	#include <dirent.h>

	#include <algorithm>
	#include <memory>

	#include <android-base/file.h>
	#include <android-base/logging.h>
	#include <android-base/properties.h>
	#include <android-base/strings.h>
	#include <log/log.h>

	#include "utils.h"

	namespace android::nativeloader {

	using namespace std::string_literals;

	namespace {

	constexpr const char* kDefaultPublicLibrariesFile = "/etc/public.libraries.txt";
	constexpr const char* kExtendedPublicLibrariesFilePrefix = "public.libraries-";
	constexpr const char* kExtendedPublicLibrariesFileSuffix = ".txt";
	constexpr const char* kVendorPublicLibrariesFile = "/vendor/etc/public.libraries.txt";
	constexpr const char* kLlndkLibrariesFile = "/system/etc/llndk.libraries.txt";
	constexpr const char* kVndkLibrariesFile = "/system/etc/vndksp.libraries.txt";

	const std::vector<const std::string> kRuntimePublicLibraries = {
	"libicuuc.so",
	"libicui18n.so",
	};

	constexpr const char* kRuntimeApexLibPath = "/apex/com.android.runtime/" LIB;

	// TODO(b/130388701): do we need this?
	std::string root_dir() {
	static const char* android_root_env = getenv("ANDROID_ROOT");
	return android_root_env != nullptr ? android_root_env : "/system";
	}

	bool debuggable() {
	static bool debuggable = android::base::GetBoolProperty("ro.debuggable", false);
	return debuggable;
	}

	std::string vndk_version_str() {
	static std::string version = android::base::GetProperty("ro.vndk.version", "");
	if (version != "" && version != "current") {
	return "." + version;
	}
	return "";
	}

	// For debuggable platform builds use ANDROID_ADDITIONAL_PUBLIC_LIBRARIES environment
	// variable to add libraries to the list. This is intended for platform tests only.
	std::string additional_public_libraries() {
	if (debuggable()) {
	const char* val = getenv("ANDROID_ADDITIONAL_PUBLIC_LIBRARIES");
	return val ? val : "";
	}
	return "";
	}

	void InsertVndkVersionStr(std::string* file_name) {
	CHECK(file_name != nullptr);
	size_t insert_pos = file_name->find_last_of(".");
	if (insert_pos == std::string::npos) {
	insert_pos = file_name->length();
	}
	file_name->insert(insert_pos, vndk_version_str());
	}

	const std::function<bool(const std::string&, std::string*)> always_true =
	[](const std::string&, std::string*) { return true; };

	bool ReadConfig(const std::string& configFile, std::vector<std::string>* sonames,
	const std::function<bool(const std::string& /* soname */,
	std::string* /* error_msg */)>& check_soname,
	std::string* error_msg = nullptr) {
	// Read list of public native libraries from the config file.
	std::string file_content;
	if (!base::ReadFileToString(configFile, &file_content)) {
	if (error_msg) *error_msg = strerror(errno);
	return false;
	}

	std::vector<std::string> lines = base::Split(file_content, "\n");

	for (auto& line : lines) {
	auto trimmed_line = base::Trim(line);
	if (trimmed_line[0] == '#' \|\| trimmed_line.empty()) {
	continue;
	}
	size_t space_pos = trimmed_line.rfind(' ');
	if (space_pos != std::string::npos) {
	std::string type = trimmed_line.substr(space_pos + 1);
	if (type != "32" && type != "64") {
	if (error_msg) *error_msg = "Malformed line: " + line;
	return false;
	}
	#if defined(__LP64__)
	// Skip 32 bit public library.
	if (type == "32") {
	continue;
	}
	#else
	// Skip 64 bit public library.
	if (type == "64") {
	continue;
	}
	#endif
	trimmed_line.resize(space_pos);
	}

	if (check_soname(trimmed_line, error_msg)) {
	sonames->push_back(trimmed_line);
	} else {
	return false;
	}
	}
	return true;
	}

	void ReadExtensionLibraries(const char* dirname, std::vector<std::string>* sonames) {
	std::unique_ptr<DIR, decltype(&closedir)> dir(opendir(dirname), closedir);
	if (dir != nullptr) {
	// Failing to opening the dir is not an error, which can happen in
	// webview_zygote.
	while (struct dirent* ent = readdir(dir.get())) {
	if (ent->d_type != DT_REG && ent->d_type != DT_LNK) {
	continue;
	}
	const std::string filename(ent->d_name);
	std::string_view fn = filename;
	if (android::base::ConsumePrefix(&fn, kExtendedPublicLibrariesFilePrefix) &&
	android::base::ConsumeSuffix(&fn, kExtendedPublicLibrariesFileSuffix)) {
	const std::string company_name(fn);
	const std::string config_file_path = dirname + "/"s + filename;
	LOG_ALWAYS_FATAL_IF(
	company_name.empty(),
	"Error extracting company name from public native library list file path \"%s\"",
	config_file_path.c_str());

	std::string error_msg;

	LOG_ALWAYS_FATAL_IF(
	!ReadConfig(config_file_path, sonames,
	[&company_name](const std::string& soname, std::string* error_msg) {
	if (android::base::StartsWith(soname, "lib") &&
	android::base::EndsWith(soname, "." + company_name + ".so")) {
	return true;
	} else {
	*error_msg = "Library name \"" + soname +
	"\" does not end with the company name: " + company_name +
	".";
	return false;
	}
	},
	&error_msg),
	"Error reading public native library list from \"%s\": %s", config_file_path.c_str(),
	error_msg.c_str());
	}
	}
	}
	}

	static std::string InitDefaultPublicLibraries() {
	std::string config_file = root_dir() + kDefaultPublicLibrariesFile;
	std::vector<std::string> sonames;
	std::string error_msg;
	LOG_ALWAYS_FATAL_IF(!ReadConfig(config_file, &sonames, always_true, &error_msg),
	"Error reading public native library list from \"%s\": %s",
	config_file.c_str(), error_msg.c_str());

	std::string additional_libs = additional_public_libraries();
	if (!additional_libs.empty()) {
	auto vec = base::Split(additional_libs, ":");
	std::copy(vec.begin(), vec.end(), std::back_inserter(sonames));
	}

	// Remove the public libs in the runtime namespace.
	// These libs are listed in public.android.txt, but we don't want the rest of android
	// in default namespace to dlopen the libs.
	// For example, libicuuc.so is exposed to classloader namespace from runtime namespace.
	// Unfortunately, it does not have stable C symbols, and default namespace should only use
	// stable symbols in libandroidicu.so. http://b/120786417
	for (const std::string& lib_name : kRuntimePublicLibraries) {
	std::string path(kRuntimeApexLibPath);
	path.append("/").append(lib_name);

	struct stat s;
	// Do nothing if the path in /apex does not exist.
	// Runtime APEX must be mounted since libnativeloader is in the same APEX
	if (stat(path.c_str(), &s) != 0) {
	continue;
	}

	auto it = std::find(sonames.begin(), sonames.end(), lib_name);
	if (it != sonames.end()) {
	sonames.erase(it);
	}
	}
	return android::base::Join(sonames, ':');
	}

	static std::string InitRuntimePublicLibraries() {
	CHECK(sizeof(kRuntimePublicLibraries) > 0);
	std::string list = android::base::Join(kRuntimePublicLibraries, ":");

	std::string additional_libs = additional_public_libraries();
	if (!additional_libs.empty()) {
	list = list + ':' + additional_libs;
	}
	return list;
	}

	static std::string InitVendorPublicLibraries() {
	// This file is optional, quietly ignore if the file does not exist.
	std::vector<std::string> sonames;
	ReadConfig(kVendorPublicLibrariesFile, &sonames, always_true, nullptr);
	return android::base::Join(sonames, ':');
	}

	// read /system/etc/public.libraries-<companyname>.txt and
	// /product/etc/public.libraries-<companyname>.txt which contain partner defined
	// system libs that are exposed to apps. The libs in the txt files must be
	// named as lib<name>.<companyname>.so.
	static std::string InitExtendedPublicLibraries() {
	std::vector<std::string> sonames;
	ReadExtensionLibraries("/system/etc", &sonames);
	ReadExtensionLibraries("/product/etc", &sonames);
	return android::base::Join(sonames, ':');
	}

	static std::string InitLlndkLibraries() {
	std::string config_file = kLlndkLibrariesFile;
	InsertVndkVersionStr(&config_file);
	std::vector<std::string> sonames;
	ReadConfig(config_file, &sonames, always_true, nullptr);
	return android::base::Join(sonames, ':');
	}

	static std::string InitVndkspLibraries() {
	std::string config_file = kVndkLibrariesFile;
	InsertVndkVersionStr(&config_file);
	std::vector<std::string> sonames;
	ReadConfig(config_file, &sonames, always_true, nullptr);
	return android::base::Join(sonames, ':');
	}

	} // namespace

	const std::string& default_public_libraries() {
	static std::string list = InitDefaultPublicLibraries();
	return list;
	}

	const std::string& runtime_public_libraries() {
	static std::string list = InitRuntimePublicLibraries();
	return list;
	}

	const std::string& vendor_public_libraries() {
	static std::string list = InitVendorPublicLibraries();
	return list;
	}

	const std::string& extended_public_libraries() {
	static std::string list = InitExtendedPublicLibraries();
	return list;
	}

	const std::string& llndk_libraries() {
	static std::string list = InitLlndkLibraries();
	return list;
	}

	const std::string& vndksp_libraries() {
	static std::string list = InitVndkspLibraries();
	return list;
	}

	} // namespace android::nativeloader