class Net::SSH::Authentication::Methods::None

def authenticate(next_service, user = "", password = "")
  send_message(userauth_request(user, next_service, "none"))
  message = session.next_message
  case message.type
  when USERAUTH_SUCCESS
    debug { "none succeeded" }
    return true
  when USERAUTH_FAILURE
    debug { "none failed" }
    raise Net::SSH::Authentication::DisallowedMethod unless
      message[:authentications].split(/,/).include? 'none'
    return false
  else
    raise Net::SSH::Exception, "unexpected reply to USERAUTH_REQUEST: #{message.type} (#{message.inspect})"
  end
end