/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
/*
 * Copyright (c) 2013-2020 Regents of the University of California.
 *
 * This file is part of ndn-cxx library (NDN C++ library with eXperimental eXtensions).
 *
 * ndn-cxx library is free software: you can redistribute it and/or modify it under the
 * terms of the GNU Lesser General Public License as published by the Free Software
 * Foundation, either version 3 of the License, or (at your option) any later version.
 *
 * ndn-cxx library is distributed in the hope that it will be useful, but WITHOUT ANY
 * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
 * PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more details.
 *
 * You should have received copies of the GNU General Public License and GNU Lesser
 * General Public License along with ndn-cxx, e.g., in COPYING.md file.  If not, see
 * <http://www.gnu.org/licenses/>.
 *
 * See AUTHORS.md for complete list of ndn-cxx authors and contributors.
 */

#ifndef NDN_SECURITY_SECURITY_COMMON_HPP
#define NDN_SECURITY_SECURITY_COMMON_HPP

#include "ndn-cxx/detail/common.hpp"

#include <vector>

namespace ndn {

namespace signed_interest {

const ssize_t POS_SIG_VALUE = -1;
const ssize_t POS_SIG_INFO = -2;

/** \brief minimal number of components for Signed Interest
 *  \sa https://redmine.named-data.net/projects/ndn-cxx/wiki/SignedInterest
 */
const size_t MIN_SIZE = 2;

} // namespace signed_interest

namespace command_interest {

using signed_interest::POS_SIG_VALUE;
using signed_interest::POS_SIG_INFO;
const ssize_t POS_RANDOM_VAL = -3;
const ssize_t POS_TIMESTAMP = -4;

/** \brief minimal number of components for Command Interest
 *  \sa https://redmine.named-data.net/projects/ndn-cxx/wiki/CommandInterest
 */
const size_t MIN_SIZE = 4;

} // namespace command_interest

/// Represents a range of distcontiguous buffers as input to a security operation
typedef std::vector<std::pair<const uint8_t*, size_t>> InputBuffers;

/**
 * @brief The type of KeyId component in a key name.
 */
enum class KeyIdType {
  /**
   * @brief User-specified key id.
   *
   * It is the user's responsibility to ensure the uniqueness of the key names.
   */
  USER_SPECIFIED = 0,
  /**
   * @brief Use the SHA-256 hash of the public key as key id.
   *
   * This KeyIdType guarantees the uniqueness of the key names.
   */
  SHA256 = 1,
  /**
   * @brief Use a 64-bit random number as key id.
   *
   * This KeyIdType provides uniqueness (with very high probability) of the key names.
   */
  RANDOM = 2,
};

std::ostream&
operator<<(std::ostream& os, KeyIdType keyIdType);

/**
 * @brief The type of a cryptographic key.
 */
enum class KeyType {
  NONE = 0, ///< Unknown or unsupported key type
  RSA,      ///< RSA key, supports sign/verify and encrypt/decrypt operations
  EC,       ///< Elliptic Curve key (e.g. for ECDSA), supports sign/verify operations
  AES,      ///< AES key, supports encrypt/decrypt operations
  HMAC,     ///< HMAC key, supports sign/verify operations
};

std::ostream&
operator<<(std::ostream& os, KeyType keyType);

enum class DigestAlgorithm {
  NONE = 0,
  SHA224,
  SHA256,
  SHA384,
  SHA512,
  BLAKE2B_512,
  BLAKE2S_256,
  SHA3_224,
  SHA3_256,
  SHA3_384,
  SHA3_512,
};

std::ostream&
operator<<(std::ostream& os, DigestAlgorithm algorithm);

enum class BlockCipherAlgorithm {
  NONE,
  AES_CBC,
};

std::ostream&
operator<<(std::ostream& os, BlockCipherAlgorithm algorithm);

enum class CipherOperator {
  DECRYPT,
  ENCRYPT,
};

std::ostream&
operator<<(std::ostream& os, CipherOperator op);

} // namespace ndn

#endif // NDN_SECURITY_SECURITY_COMMON_HPP