main.go

package main

import (
	"context"
	"crypto/rand"
	"flag"
	"fmt"
	"net"
	"time"

	ic "github.com/libp2p/go-libp2p-crypto"
	peer "github.com/libp2p/go-libp2p-peer"
	libp2ptls "github.com/libp2p/go-libp2p-tls"
)

func main() {
	if err := startServer(); err != nil {
		panic(err)
	}
}

func startServer() error {
	port := flag.Int("p", 5533, "port")
	flag.Parse()

	priv, _, err := ic.GenerateECDSAKeyPair(rand.Reader)
	if err != nil {
		return err
	}
	id, err := peer.IDFromPrivateKey(priv)
	if err != nil {
		return err
	}
	fmt.Printf("Generated new peer with an ECDSA key. Peer ID: %s\n", id.Pretty())
	tp, err := libp2ptls.New(priv)
	if err != nil {
		return err
	}

	ln, err := net.Listen("tcp", fmt.Sprintf("localhost:%d", *port))
	if err != nil {
		return err
	}
	fmt.Printf("Listening for new connections on %s\n", ln.Addr())
	fmt.Printf("Now run the following command in a separate terminal:\n")
	fmt.Printf("\tgo run example/client/main.go -p %d -id %s\n", *port, id.Pretty())

	for {
		conn, err := ln.Accept()
		if err != nil {
			return err
		}
		fmt.Printf("Accepted raw connection from %s\n", conn.RemoteAddr())
		go func() {
			if err := handleConn(tp, conn); err != nil {
				fmt.Printf("Error handling connection from %s: %s\n", conn.RemoteAddr(), err)
			}
		}()
	}
}

func handleConn(tp *libp2ptls.Transport, conn net.Conn) error {
	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
	defer cancel()
	sconn, err := tp.SecureInbound(ctx, conn)
	if err != nil {
		return err
	}
	fmt.Printf("Authenticated client: %s\n", sconn.RemotePeer().Pretty())
	fmt.Fprintf(sconn, "Hello client!")
	fmt.Printf("Closing connection to %s\n", conn.RemoteAddr())
	return sconn.Close()
}