uup

README

U Up?

A small service to test whether your port is internet accessible.

Written in Go, in a fit of frustration.

Limitations

TCP

The TCP checker returns success on an opened connection. It does not read or write any data to that connection.

Quic

For the sake of security, various cryptographic properties are not user-specified. Thus, the Quic checker does not verify TLS certificates on connect. This also means the connect may fail with CRYPTO_ERROR in various ways, as the host rejects the arbitrary checker certificate that also lacks the correct application protocol names. Consequently, the Quic checker returns success on an opened connection OR A CRYPTO_ERROR

UDP Checker

The UDP checker sends up to k datagrams with message U UP? to the user-specified port. It assumes success if it receives any packet back. If the protocol does not reply to this message, it still appears down, though it need not be.

(Imagined) FAQs

Why doesn't the JSON response return my IP address?

Because I don't want people using this service one that provides them with their IP address. Use someone else's STUN service for that.

Why can't I specify the IP address I'm curious about?

Because this isn't a general port scanner. It's a service to help you write and debug your local network, especially if you are trying to write P2P applications (which I want you to do).

Why can't I specify the payload?

Because this service exists only to verify the port is accessible. If you could specify the payload, it would provide a free service for anonymously executing attacks against the network you happen to be on, which might not be yours (evil Mallory!).

Is this service logged?

Hrm.

Documentation

Index

• Constants
• Variables
• func RunCLI()

Constants

const Version = "0.0.1"

Variables

var StartCmd = &cobra.Command{
	Use:   "start",
	Short: "start the uup service",
	Run: func(cmd *cobra.Command, args []string) {
		logger, finalizer := service.InitializeLogger()
		defer finalizer()

		opts, useTLS, clientTimeout := buildOptsFromCLIParams()

		s, err := service.New(opts...)
		if err != nil {
			log.Fatalln(err)
		}
		s.ListenAndServe(context.Background())

		srv := &http.Server{
			Handler:      s.Routes(),
			Addr:         httpAddr,
			WriteTimeout: clientTimeout,
			ReadTimeout:  clientTimeout,
		}

		if useTLS {
			if httpsRedirectorAddr != "" {

				ctx, cancel := context.WithCancel(context.Background())
				defer cancel()
				err := service.StartHTTPToHTTPSRedirector(ctx, httpsRedirectorAddr, httpAddr, time.Second)
				if err != nil {
					os.Exit(1)
				}
			}
			logger.Info("https server listening", zap.String("addr", httpAddr))
			log.Fatal(srv.ListenAndServeTLS(tlsCertFilePath, tlsKeyFilePath))
		} else {
			logger.Info("http server listening", zap.String("addr", httpAddr))
			log.Fatal(srv.ListenAndServe())
		}
	},
}

Functions

func RunCLI

func RunCLI()

TODO: http redirect