feat: implement mDNS discovery

core/device/tun_linux.go

@@ -11,6 +11,7 @@ import (
 	"unsafe"
 
 	"github.com/wlynxg/NetHive/pkgs/command"
+	"github.com/wlynxg/NetHive/pkgs/system"
 
 	"golang.org/x/sys/unix"
 )
@@ -18,15 +19,6 @@ import (
 // https://man7.org/linux/man-pages/man7/netdevice.7.html
 type ifReq [40]byte
 
-// https://man7.org/linux/man-pages/man2/ioctl.2.html
-func ioctl(fd uintptr, request uintptr, argp uintptr) error {
-	_, _, err := unix.Syscall(unix.SYS_IOCTL, fd, request, argp)
-	if err != 0 {
-		return os.NewSyscallError("ioctl", err)
-	}
-	return nil
-}
-
 // compilation time interface check
 var _ Device = new(tun)
 
@@ -107,7 +99,7 @@ func (t *tun) changeState(state bool) error {
 	} else {
 		*(*uint16)(unsafe.Pointer(&ifr[unix.IFNAMSIZ])) &^= syscall.IFF_UP
 	}
-	err = ioctl(uintptr(fd), unix.SIOCGIFFLAGS, uintptr(unsafe.Pointer(&ifr[0])))
+	err = system.Ioctl(uintptr(fd), unix.SIOCSIFFLAGS, uintptr(unsafe.Pointer(&ifr[0])))
 	if err != nil {
 		return err
 	}
@@ -124,7 +116,7 @@ func (t *tun) getNameFromSys() (string, error) {
 	var ifr ifReq
 	var errno syscall.Errno
 	err = conn.Control(func(fd uintptr) {
-		ioctl(fd, unix.TUNGETIFF, uintptr(unsafe.Pointer(&ifr[0])))
+		system.Ioctl(fd, unix.TUNGETIFF, uintptr(unsafe.Pointer(&ifr[0])))
 	})
 	if err != nil || errno != 0 {
 		return "", fmt.Errorf("failed to get name of TUN device: %w", err)
@@ -147,7 +139,7 @@ func (t *tun) getMTUFromSys() (int, error) {
 
 	var ifr ifReq
 	copy(ifr[:], t.name)
-	err = ioctl(uintptr(fd), unix.SIOCGIFMTU, uintptr(unsafe.Pointer(&ifr[0])))
+	err = system.Ioctl(uintptr(fd), unix.SIOCGIFMTU, uintptr(unsafe.Pointer(&ifr[0])))
 	if err != nil {
 		return -1, err
 	}
@@ -164,7 +156,7 @@ func (t *tun) setMTU(n int) error {
 	var ifr ifReq
 	copy(ifr[:], t.name)
 	*(*uint32)(unsafe.Pointer(&ifr[unix.IFNAMSIZ])) = uint32(n)
-	err = ioctl(uintptr(fd), unix.SIOCSIFMTU, uintptr(unsafe.Pointer(&ifr[0])))
+	err = system.Ioctl(uintptr(fd), unix.SIOCSIFMTU, uintptr(unsafe.Pointer(&ifr[0])))
 	if err != nil {
 		return err
 	}
@@ -180,7 +172,7 @@ func (t *tun) getIFIndex() (int32, error) {
 
 	var ifr ifReq
 	copy(ifr[:], t.name)
-	err = ioctl(uintptr(fd), unix.SIOCGIFINDEX, uintptr(unsafe.Pointer(&ifr[0])))
+	err = system.Ioctl(uintptr(fd), unix.SIOCGIFINDEX, uintptr(unsafe.Pointer(&ifr[0])))
 	if err != nil {
 		return 0, err
 	}

core/engine/conn.go

@@ -21,6 +21,7 @@ func (e *Engine) addConnByDst(dst netip.Addr) (PacketChan, error) {
 		e.routeTable.m.Range(func(key string, value netip.Prefix) bool {
 			if value.Addr().Compare(dst) == 0 {
 				conn = make(PacketChan, ChanSize)
+				e.routeTable.addr.Store(dst, conn)
 				go func() {
 					defer e.routeTable.id.Delete(key)
 					defer e.routeTable.addr.Delete(dst)
@@ -77,7 +78,7 @@ func (e *Engine) addConn(peerChan PacketChan, id string) {
 		if err != nil {
 			peerc, err := e.discovery.FindPeers(e.ctx, id)
 			if err != nil {
-				e.log.Warnf("Finding node by dht %s failed because %s", string(id), err)
+				e.log.Warnf("Finding node by dht %s failed because %s", id, err)
 				return
 			}
 
@@ -89,7 +90,7 @@ func (e *Engine) addConn(peerChan PacketChan, id string) {
 					}
 				}
 			}
-			e.log.Warnf("Connection establishment with node %s failed", string(id))
+			e.log.Warnf("Connection establishment with node %s failed", id)
 			return
 		}
 	}
@@ -98,19 +99,19 @@ func (e *Engine) addConn(peerChan PacketChan, id string) {
 		return
 	}
 
-	e.log.Infof("Peer [%s] connect success", string(id))
+	e.log.Infof("Peer [%s] connect success", id)
 	defer stream.Close()
 
 	go func() {
 		defer stream.Close()
 		_, err := io.Copy(stream, dev)
 		if err != nil && err != io.EOF {
-			e.log.Errorf("Peer [%s] stream write error: %s", string(id), err)
+			e.log.Errorf("Peer [%s] stream write error: %s", id, err)
 		}
 	}()
 
 	_, err = io.Copy(dev, stream)
 	if err != nil && err != io.EOF {
-		e.log.Errorf("Peer [%s] stream read error: %s", string(id), err)
+		e.log.Errorf("Peer [%s] stream read error: %s", id, err)
 	}
 }

core/engine/engine.go

@@ -3,11 +3,12 @@ package engine
 import (
 	"context"
 	"fmt"
-	"github.com/wlynxg/NetHive/core/route"
 	"io"
 	"net/netip"
 	"sync"
 
+	"github.com/wlynxg/NetHive/core/route"
+
 	"github.com/wlynxg/NetHive/core/config"
 	"github.com/wlynxg/NetHive/core/device"
 	"github.com/wlynxg/NetHive/core/protocol"
@@ -64,8 +65,9 @@ func Run(cfg *config.Config) (*Engine, error) {
 		err error
 	)
 
-	e.log = mlog.New("engine")
 	e.cfg = cfg
+	mlog.SetOutputTypes(cfg.LogConfigs...)
+	e.log = mlog.New("engine")
 	e.ctx, e.cancel = context.WithCancel(context.Background())
 	e.devWriter = make(PacketChan, ChanSize)
 	e.devReader = make(PacketChan, ChanSize)
@@ -97,7 +99,7 @@ func (e *Engine) Run() error {
 	var err error
 	defer e.cancel()
 
-	// create tun
+	// TUN init
 	e.device, err = device.CreateTUN(e.cfg.TUNName, e.cfg.MTU)
 	if err != nil {
 		return err
@@ -108,17 +110,6 @@ func (e *Engine) Run() error {
 		return err
 	}
 
-	for id, prefix := range e.cfg.PeersRouteTable {
-		e.routeTable.m.Store(id, prefix)
-
-		err := route.Add(name, prefix)
-		if err != nil {
-			e.log.Warnf("fail to add %s's route: %s", id, prefix)
-			continue
-		}
-		e.log.Debugf("successfully add %s's route: %s", id, prefix)
-	}
-
 	if err := e.device.AddAddress(e.cfg.LocalAddr); err != nil {
 		return err
 	}
@@ -127,6 +118,18 @@ func (e *Engine) Run() error {
 		return err
 	}
 
+	for id, prefix := range e.cfg.PeersRouteTable {
+		e.routeTable.m.Store(id, prefix)
+
+		err := route.Add(name, prefix)
+		if err != nil {
+			e.log.Warnf("fail to add %s's route %s: %v", id, prefix, err)
+			continue
+		}
+		e.log.Debugf("successfully add %s's route: %s", id, prefix)
+	}
+
+	// DHT init
 	wg := sync.WaitGroup{}
 	for _, info := range e.cfg.Bootstraps {
 		addrInfo, err := peer.AddrInfoFromString(info)
@@ -145,6 +148,13 @@ func (e *Engine) Run() error {
 	}
 	wg.Wait()
 
+	if e.cfg.EnableMDNS {
+		err := e.EnableMdns()
+		if err != nil {
+			return err
+		}
+	}
+
 	e.host.SetStreamHandler(VPNStreamProtocol, e.VPNHandler)
 	util.Advertise(e.ctx, e.discovery, e.host.ID().String())
 

core/engine/mdns.go

@@ -4,9 +4,49 @@ import (
 	"time"
 
 	"github.com/libp2p/go-libp2p/core/peer"
+	"github.com/libp2p/go-libp2p/core/peerstore"
+	"github.com/libp2p/go-libp2p/p2p/discovery/mdns"
 )
 
-func (e *Engine) HandlePeerFound(pi peer.AddrInfo) {
-	e.log.Infof("find %s by mDNS", pi)
-	e.host.Peerstore().AddAddrs(pi.ID, pi.Addrs, 5*time.Minute)
+const (
+	MDNSRetryInterval = 5 * time.Minute
+)
+
+func (e *Engine) HandlePeerFound(info peer.AddrInfo) {
+	e.log.Debugf("mDNS get node addr info: %s", info)
+	e.host.Peerstore().AddAddrs(info.ID, info.Addrs, peerstore.AddressTTL)
+}
+
+func (e *Engine) EnableMdns() error {
+	if e.mdns == nil {
+		// init mdns serve
+		e.mdns = mdns.NewMdnsService(e.host, "_p2proxy._udp", e)
+	}
+	go e.mdnsLoop()
+	return nil
+}
+
+func (e *Engine) mdnsLoop() {
+	if err := e.mdns.Start(); err != nil {
+		e.log.Warnf("fail to run mDNS service for the %dth time: %v", 1, err)
+	} else {
+		e.log.Infof("successfully run mDNS service!")
+		return
+	}
+
+	ticker := time.NewTicker(MDNSRetryInterval)
+	defer ticker.Stop()
+
+	for i := 2; ; i++ {
+		select {
+		case <-e.ctx.Done():
+		case <-ticker.C:
+			if err := e.mdns.Start(); err != nil {
+				e.log.Warnf("fail to run mDNS service for the %dth time: %v", 1, err)
+			} else {
+				e.log.Infof("successfully run mDNS service!")
+				return
+			}
+		}
+	}
 }