blob: ab8f80c88c92b240493f0f9ece4475cd1c273b94 [file] [log] [blame]
// Copyright 2023 The ChromiumOS Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "init/startup/test_mode_mount_helper.h"
#include <sys/stat.h>
#include <memory>
#include <optional>
#include <string>
#include <utility>
#include <vector>
#include <base/files/file_enumerator.h>
#include <base/files/file_path.h>
#include <base/files/file_util.h>
#include <base/logging.h>
#include <base/values.h>
#include <brillo/files/file_util.h>
#include <brillo/process/process.h>
#include <libstorage/platform/platform.h>
#include "init/startup/flags.h"
#include "init/startup/mount_helper.h"
#include "init/startup/mount_var_home_interface.h"
#include "init/startup/security_manager.h"
#include "init/startup/startup_dep_impl.h"
namespace {
// Flag file indicating that mount encrypted stateful failed last time.
// If the file is present and mount_encrypted failed again, machine would
// enter self-repair mode.
constexpr char kMountEncryptedFailedFile[] = "mount_encrypted_failed";
constexpr char kSysKeyLogFile[] = "run/chromeos_startup/create_system_key.log";
} // namespace
namespace startup {
// Constructor for TestModeMountHelper when the device is
// not in dev mode.
libstorage::Platform* platform,
StartupDep* startup_dep,
const Flags& flags,
const base::FilePath& root,
const base::FilePath& stateful,
std::unique_ptr<MountVarAndHomeChronosInterface> impl,
: MountHelper(platform,
std::move(storage_container_factory)) {}
bool TestModeMountHelper::DoMountVarAndHomeChronos() {
// If this a TPM 2.0 device that supports encrypted stateful, creates and
// persists a system key into NVRAM and backs the key up if it doesn't exist.
// If the call create_system_key is successful, mount_var_and_home_chronos
// will skip the normal system key generation procedure; otherwise, it will
// generate and persist a key via its normal workflow.
if (flags_.sys_key_util) {
LOG(INFO) << "Creating System Key";
std::string output;
CreateSystemKey(platform_, root_, stateful_, startup_dep_, &output);
base::FilePath log_file = root_.Append(kSysKeyLogFile);
platform_->WriteStringToFile(log_file, output);
base::FilePath encrypted_failed = stateful_.Append(kMountEncryptedFailedFile);
bool ret;
uid_t uid;
if (!platform_->GetOwnership(encrypted_failed, &uid, nullptr,
false /* follow_links */) ||
(uid != getuid())) {
// This is the default path
// Try to use the original handler in chromeos_startup.
// When it fails, we will reboot and try again below.
return MountVarAndHomeChronos();
ret = MountVarAndHomeChronos();
if (!ret) {
// Try to re-construct encrypted folders, otherwise such a failure will lead
// to wiping whole stateful partition (including all helpful programs in
// /usr/local/bin and sshd).
std::string msg("Failed mounting var and home/chronos; re-created.");
std::vector<std::string> crash_args{"--mount_failure",
base::FilePath backup = stateful_.Append("corrupted_encryption");
if (!platform_->SetPermissions(backup, 0755)) {
PLOG(WARNING) << "chmod failed for " << backup.value();
std::unique_ptr<libstorage::FileEnumerator> enumerator(
platform_->GetFileEnumerator(stateful_, false /* recursive */,
for (base::FilePath path = enumerator->Next(); !path.empty();
path = enumerator->Next()) {
base::FilePath to_path = backup.Append(path.BaseName());
platform_->Rename(path, to_path, true /* cros_fs */);
return MountVarAndHomeChronos();
return true;
} // namespace startup