Class KeyEncryptionKey

cpp/src/parquet/encryption/key_encryption_key.h:34–56

In the double wrapping mode, each "data encryption key" (DEK) is encrypted with a “key encryption key” (KEK), that in turn is encrypted with a "master encryption key" (MEK). In a writer process, a random KEK is generated for each MEK ID, and cached in a map. This allows to perform an interaction with a KMS server only once for each MEK, in order to wrap its KEK. "Data encryption key

// MEK, in order to wrap its KEK. "Data encryption key" (DEK) wrapping is performed
// locally, and does not involve an interaction with a KMS server.
class KeyEncryptionKey {
 public:
  KeyEncryptionKey(::arrow::util::SecureString kek_bytes, std::string kek_id,
                   std::string encoded_wrapped_kek)
      : kek_bytes_(std::move(kek_bytes)),
        kek_id_(std::move(kek_id)),
        encoded_kek_id_(::arrow::util::base64_encode(kek_id_)),
        encoded_wrapped_kek_(std::move(encoded_wrapped_kek)) {}

  const ::arrow::util::SecureString& kek_bytes() const { return kek_bytes_; }

  const std::string& kek_id() const { return kek_id_; }

  const std::string& encoded_kek_id() const { return encoded_kek_id_; }

  const std::string& encoded_wrapped_kek() const { return encoded_wrapped_kek_; }

 private:
  ::arrow::util::SecureString kek_bytes_;
  std::string kek_id_;
  std::string encoded_kek_id_;
  std::string encoded_wrapped_kek_;
};

}  // namespace parquet::encryption