Add for engine

client/internal/engine.go

@@ -33,6 +33,8 @@ import (
 	"github.com/netbirdio/netbird/client/internal/acl"
 	"github.com/netbirdio/netbird/client/internal/dns"
 	"github.com/netbirdio/netbird/client/internal/dnsfwd"
+	"github.com/netbirdio/netbird/client/internal/lazyconn"
+	lazyConnManager "github.com/netbirdio/netbird/client/internal/lazyconn/manager"
 	"github.com/netbirdio/netbird/client/internal/networkmonitor"
 	"github.com/netbirdio/netbird/client/internal/peer"
 	"github.com/netbirdio/netbird/client/internal/peer/guard"
@@ -131,6 +133,8 @@ type Engine struct {
 	// peerConns is a map that holds all the peers that are known to this peer
 	peerStore *peerstore.Store
 
+	lazyConnMgr *lazyConnManager.Manager
+
 	beforePeerHook nbnet.AddHookFunc
 	afterPeerHook  nbnet.RemoveHookFunc
 
@@ -285,11 +289,12 @@ func (e *Engine) Stop() error {
 	e.statusRecorder.UpdateDNSStates([]peer.NSGroupState{})
 	e.statusRecorder.UpdateRelayStates([]relay.ProbeResult{})
 
-	err := e.removeAllPeers()
-	if err != nil {
+	if err := e.removeAllPeers(); err != nil {
 		return fmt.Errorf("failed to remove all peers: %s", err)
 	}
 
+	e.lazyConnMgr.Close()
+
 	if e.cancel != nil {
 		e.cancel()
 	}
@@ -401,6 +406,10 @@ func (e *Engine) Start() error {
 		return fmt.Errorf("up wg interface: %w", err)
 	}
 
+	e.lazyConnMgr = lazyConnManager.NewManager(e.wgInterface)
+	go e.lazyConnMgr.Start()
+	go e.receiveLazyConnEvents()
+
 	if e.firewall != nil {
 		e.acl = acl.NewDefaultManager(e.firewall)
 	}
@@ -1140,7 +1149,19 @@ func (e *Engine) addNewPeer(peerConfig *mgmProto.RemotePeerConfig) error {
 		log.Warnf("error adding peer %s to status recorder, got error: %v", peerKey, err)
 	}
 
-	conn.Open()
+	peerKeyParsed, err := wgtypes.ParseKey(peerKey)
+	if err != nil {
+		return err
+	}
+
+	lazyPeerCfg := lazyconn.PeerConfig{
+		PublicKey:  peerKeyParsed,
+		AllowedIPs: peerIPs,
+	}
+	if err := e.lazyConnMgr.AddPeer(lazyPeerCfg); err != nil {
+		return err
+	}
+
 	return nil
 }
 
@@ -1221,6 +1242,14 @@ func (e *Engine) receiveSignalEvents() {
 				return fmt.Errorf("wrongly addressed message %s", msg.Key)
 			}
 
+			peerKeyParsed, err := wgtypes.ParseKey(msg.Key)
+			if err != nil {
+				return err
+			}
+			if ok := e.lazyConnMgr.RemovePeer(peerKeyParsed); ok {
+				conn.Open()
+			}
+
 			switch msg.GetBody().Type {
 			case sProto.Body_OFFER:
 				remoteCred, err := signal.UnMarshalCredential(msg)
@@ -1346,6 +1375,12 @@ func (e *Engine) parseNATExternalIPMappings() []string {
 }
 
 func (e *Engine) close() {
+	log.Debugf("stop lazy connection manager")
+	if e.lazyConnMgr != nil {
+		e.lazyConnMgr.Close()
+		e.lazyConnMgr = nil
+	}
+
 	log.Debugf("removing Netbird interface %s", e.config.WgIfaceName)
 	if e.wgInterface != nil {
 		if err := e.wgInterface.Close(); err != nil {
@@ -1770,6 +1805,23 @@ func (e *Engine) Address() (netip.Addr, error) {
 	return ip.Unmap(), nil
 }
 
+func (e *Engine) receiveLazyConnEvents() {
+	for {
+		select {
+		case peerID := <-e.lazyConnMgr.PeerActivityChan:
+			e.syncMsgMux.Lock()
+			peerConn, ok := e.peerStore.PeerConn(peerID.String())
+			if !ok {
+				e.syncMsgMux.Unlock()
+				continue
+			}
+			peerConn.Open()
+			e.syncMsgMux.Unlock()
+		case <-e.ctx.Done():
+		}
+	}
+}
+
 // isChecksEqual checks if two slices of checks are equal.
 func isChecksEqual(checks []*mgmProto.Checks, oChecks []*mgmProto.Checks) bool {
 	for _, check := range checks {

client/internal/peer/conn.go

@@ -166,6 +166,7 @@ func NewConn(engineCtx context.Context, config ConnConfig, statusRecorder *Statu
 // Open opens connection to the remote peer
 // It will try to establish a connection using ICE and in parallel with relay. The higher priority connection type will
 // be used.
+// todo: prevent double open
 func (conn *Conn) Open() {
 	conn.semaphore.Add(conn.ctx)
 	conn.log.Debugf("open connection to peer")