_encrypt

# File activesupport/lib/active_support/message_encryptor.rb, line 94
      def _encrypt(value)
        cipher = new_cipher
        cipher.encrypt
        cipher.key = @secret

        # Rely on OpenSSL for the initialization vector
        iv = cipher.random_iv
        cipher.auth_data = "" if aead_mode?

        encrypted_data = cipher.update(@serializer.dump(value))
        encrypted_data << cipher.final

        blob = "#{::Base64.strict_encode64 encrypted_data}--#{::Base64.strict_encode64 iv}"
        blob << "--#{::Base64.strict_encode64 cipher.auth_tag}" if aead_mode?
        blob
      end