class Net::SSH::Authentication::Methods::KeyboardInteractive

def authenticate(next_service, username, password = nil)
  debug { "trying keyboard-interactive" }
  send_message(userauth_request(username, next_service, "keyboard-interactive", "", ""))
  prompter = nil
  loop do
    message = session.next_message
    case message.type
    when USERAUTH_SUCCESS
      debug { "keyboard-interactive succeeded" }
      prompter.success if prompter
      return true
    when USERAUTH_FAILURE
      debug { "keyboard-interactive failed" }
      raise Net::SSH::Authentication::DisallowedMethod unless
        message[:authentications].split(/,/).include? 'keyboard-interactive'
      return false unless interactive?
      password = nil
      debug { "retrying keyboard-interactive" }
      send_message(userauth_request(username, next_service, "keyboard-interactive", "", ""))
    when USERAUTH_INFO_REQUEST
      name = message.read_string
      instruction = message.read_string
      debug { "keyboard-interactive info request" }
      if password.nil? && interactive? && prompter.nil?
        prompter = prompt.start(type: 'keyboard-interactive', name: name, instruction: instruction)
      end
      _ = message.read_string # lang_tag
      responses = []
      message.read_long.times do
        text = message.read_string
        echo = message.read_bool
        password_to_send = password || (prompter && prompter.ask(text, echo))
        responses << password_to_send
      end
      # if the password failed the first time around, don't try
      # and use it on subsequent requests.
      password = nil
      msg = Buffer.from(:byte, USERAUTH_INFO_RESPONSE, :long, responses.length, :string, responses)
      send_message(msg)
    else
      raise Net::SSH::Exception, "unexpected reply in keyboard interactive: #{message.type} (#{message.inspect})"
    end
  end
end

def interactive?
  options = session.transport.options || {}
  !options[:non_interactive]
end