cryptohome/storage/encrypted_container/dmcrypt_container.h

// Copyright 2021 The Chromium OS Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef CRYPTOHOME_STORAGE_ENCRYPTED_CONTAINER_DMCRYPT_CONTAINER_H_
#define CRYPTOHOME_STORAGE_ENCRYPTED_CONTAINER_DMCRYPT_CONTAINER_H_

#include "cryptohome/storage/encrypted_container/encrypted_container.h"

#include <memory>
#include <string>
#include <utility>
#include <vector>

#include <brillo/blkdev_utils/loop_device.h>
#include <brillo/blkdev_utils/device_mapper.h>

#include "cryptohome/platform.h"
#include "cryptohome/storage/encrypted_container/backing_device.h"
#include "cryptohome/storage/encrypted_container/filesystem_key.h"

namespace cryptohome {

// `DmcryptContainer` is a block-level encrypted container, complete with its
// own filesystem (by default ext4). The backing storage for the dm-crypt
// container is currently a loopback device over a sparse file.
class DmcryptContainer : public EncryptedContainer {
 public:
  DmcryptContainer(const DmcryptConfig& config,
                   std::unique_ptr<BackingDevice> backing_device,
                   const FileSystemKeyReference& key_reference,
                   Platform* platform,
                   std::unique_ptr<brillo::DeviceMapper> device_mapper);

  DmcryptContainer(const DmcryptConfig& config,
                   std::unique_ptr<BackingDevice> backing_device,
                   const FileSystemKeyReference& key_reference,
                   Platform* platform);

  ~DmcryptContainer() {}

  bool Exists() override;

  bool Purge() override;

  bool Setup(const FileSystemKey& encryption_key, bool create) override;

  bool Teardown() override;

  EncryptedContainerType GetType() override {
    return EncryptedContainerType::kDmcrypt;
  }

 private:
  // Configuration for the encrypted container.
  const std::string dmcrypt_device_name_;
  const std::string dmcrypt_cipher_;

  const std::vector<std::string> mkfs_opts_;
  const std::vector<std::string> tune2fs_opts_;

  // Backing device for the encrypted container.
  std::unique_ptr<BackingDevice> backing_device_;

  // Key reference for filesystem key.
  const FileSystemKeyReference key_reference_;

  Platform* platform_;
  std::unique_ptr<brillo::DeviceMapper> device_mapper_;
};

}  // namespace cryptohome

#endif  // CRYPTOHOME_STORAGE_ENCRYPTED_CONTAINER_DMCRYPT_CONTAINER_H_