encryptCborPhrase function

Future<Uint8List> encryptCborPhrase(String phrase, String password, [ Map<String, dynamic>? options ])

Implementation

Future<Uint8List> encryptCborPhrase(
  String phrase,
  String password, [
  Map<String, dynamic>? options,
]) async {
  final String salt = randomAsHex(64);
  final List<int> iv = randomAsU8a(16);
  String kdf = 'scrypt';
  int level = 8192;
  int n = kdf == 'pbkdf2' ? 262144 : level;
  if (options == null) {
    kdf = 'scrypt';
    level = 8192;
    n = kdf == 'pbkdf2' ? 262144 : level;
  } else {
    kdf = options['kdf'] is String ? options['kdf'] : 'scrypt';
    level = options['level'] is int ? options['level'] : 8192;
    n = kdf == 'pbkdf2' ? 262144 : level;
  }

  final Map<String, dynamic> kdfParams = {
    'salt': salt,
    'n': n,
    'r': 8,
    'p': 1,
    'dklen': 32
  };

  final List<int> encodedPassword = utf8.encode(password);
  final _KeyDerivator derivator = getDerivedKey(kdf, kdfParams);
  final List<int> derivedKey = derivator.deriveKey(encodedPassword);

  final List<int> ciphertextBytes = _encryptPhrase(
    derivator,
    Uint8List.fromList(encodedPassword),
    Uint8List.fromList(iv),
    phrase,
  );

  final List<int> macBuffer = derivedKey.sublist(16, 32) +
      ciphertextBytes +
      iv +
      ALGO_IDENTIFIER.codeUnits;

  final Uint8List mac = SHA256()
      .update(Uint8List.fromList(derivedKey))
      .update(macBuffer)
      .digest();

  return cborEncode({
    'ciphertext': ciphertextBytes,
    'cipherparams': {
      'iv': iv,
    },
    'cipher': ALGO_IDENTIFIER.plainToU8a(),
    'kdf': kdf.plainToU8a(),
    'kdfparams': cborEncode(kdfParams),
    'mac': mac,
  });
}