Integrate Rosenpass (#1153)

This PR aims to integrate Rosenpass with NetBird. It adds a manager for Rosenpass that starts a Rosenpass server and handles the managed peers. It uses the cunicu/go-rosenpass implementation. Rosenpass will then negotiate a pre-shared key every 2 minutes and apply it to the wireguard connection.

The Feature can be enabled by setting a flag during the netbird up --enable-rosenpass command.

If two peers are both support and have the Rosenpass feature enabled they will create a post-quantum secure connection. If one of the peers or both don't have this feature enabled or are running an older version that does not have this feature yet, the NetBird client will fall back to a plain Wireguard connection without pre-shared keys for those connections (keeping Rosenpass negotiation for the rest).

Additionally, this PR includes an update of all Github Actions workflows to use go version 1.21.0 as this is a requirement for the integration.

---------

Co-authored-by: braginini <bangvalo@gmail.com>
Co-authored-by: Maycon Santos <mlsmaycon@gmail.com>

client/internal/config.go

@@ -41,6 +41,7 @@ type ConfigInput struct {
 	PreSharedKey     *string
 	NATExternalIPs   []string
 	CustomDNSAddress []byte
+	RosenpassEnabled *bool
 }
 
 // Config Configuration type
@@ -54,6 +55,7 @@ type Config struct {
 	WgPort               int
 	IFaceBlackList       []string
 	DisableIPv6Discovery bool
+	RosenpassEnabled     bool
 	// SSHKey is a private SSH key in a PEM format
 	SSHKey string
 
@@ -169,6 +171,10 @@ func createNewConfig(input ConfigInput) (*Config, error) {
 		config.PreSharedKey = *input.PreSharedKey
 	}
 
+	if input.RosenpassEnabled != nil {
+		config.RosenpassEnabled = *input.RosenpassEnabled
+	}
+
 	defaultAdminURL, err := parseURL("Admin URL", DefaultAdminURL)
 	if err != nil {
 		return nil, err
@@ -247,6 +253,11 @@ func update(input ConfigInput) (*Config, error) {
 		refresh = true
 	}
 
+	if input.RosenpassEnabled != nil {
+		config.RosenpassEnabled = *input.RosenpassEnabled
+		refresh = true
+	}
+
 	if refresh {
 		// since we have new management URL, we need to update config file
 		if err := util.WriteJson(input.ConfigPath, config); err != nil {

client/internal/connect.go

@@ -235,6 +235,7 @@ func createEngineConfig(key wgtypes.Key, config *Config, peerConfig *mgmProto.Pe
 		SSHKey:               []byte(config.SSHKey),
 		NATExternalIPs:       config.NATExternalIPs,
 		CustomDNSAddress:     config.CustomDNSAddress,
+		RosenpassEnabled:     config.RosenpassEnabled,
 	}
 
 	if config.PreSharedKey != "" {

client/internal/engine.go

@@ -22,6 +22,7 @@ import (
 	"github.com/netbirdio/netbird/client/internal/acl"
 	"github.com/netbirdio/netbird/client/internal/dns"
 	"github.com/netbirdio/netbird/client/internal/peer"
+	"github.com/netbirdio/netbird/client/internal/rosenpass"
 	"github.com/netbirdio/netbird/client/internal/routemanager"
 	"github.com/netbirdio/netbird/client/internal/wgproxy"
 	nbssh "github.com/netbirdio/netbird/client/ssh"
@@ -76,6 +77,8 @@ type EngineConfig struct {
 	NATExternalIPs []string
 
 	CustomDNSAddress string
+
+	RosenpassEnabled bool
 }
 
 // Engine is a mechanism responsible for reacting on Signal and Management stream events and managing connections to the remote peers.
@@ -86,6 +89,8 @@ type Engine struct {
 	mgmClient mgm.Client
 	// peerConns is a map that holds all the peers that are known to this peer
 	peerConns map[string]*peer.Conn
+	// rpManager is a Rosenpass manager
+	rpManager *rosenpass.Manager
 
 	// syncMsgMux is used to guarantee sequential Management Service message processing
 	syncMsgMux *sync.Mutex
@@ -185,6 +190,18 @@ func (e *Engine) Start() error {
 	}
 	e.wgInterface = wgIface
 
+	if e.config.RosenpassEnabled {
+		log.Infof("rosenpass is enabled")
+		e.rpManager, err = rosenpass.NewManager(e.config.PreSharedKey, e.config.WgIfaceName)
+		if err != nil {
+			return err
+		}
+		err := e.rpManager.Run()
+		if err != nil {
+			return err
+		}
+	}
+
 	initialRoutes, dnsServer, err := e.newDnsServer()
 	if err != nil {
 		e.close()
@@ -363,7 +380,8 @@ func sendSignal(message *sProto.Message, s signal.Client) error {
 }
 
 // SignalOfferAnswer signals either an offer or an answer to remote peer
-func SignalOfferAnswer(offerAnswer peer.OfferAnswer, myKey wgtypes.Key, remoteKey wgtypes.Key, s signal.Client, isAnswer bool) error {
+func SignalOfferAnswer(offerAnswer peer.OfferAnswer, myKey wgtypes.Key, remoteKey wgtypes.Key, s signal.Client,
+	isAnswer bool) error {
 	var t sProto.Body_Type
 	if isAnswer {
 		t = sProto.Body_ANSWER
@@ -374,7 +392,7 @@ func SignalOfferAnswer(offerAnswer peer.OfferAnswer, myKey wgtypes.Key, remoteKe
 	msg, err := signal.MarshalCredential(myKey, offerAnswer.WgListenPort, remoteKey, &signal.Credential{
 		UFrag: offerAnswer.IceCredentials.UFrag,
 		Pwd:   offerAnswer.IceCredentials.Pwd,
-	}, t)
+	}, t, offerAnswer.RosenpassPubKey, offerAnswer.RosenpassAddr)
 	if err != nil {
 		return err
 	}
@@ -627,6 +645,7 @@ func (e *Engine) updateNetworkMap(networkMap *mgmProto.NetworkMap) error {
 		e.acl.ApplyFiltering(networkMap)
 	}
 	e.networkSerial = serial
+
 	return nil
 }
 
@@ -796,6 +815,26 @@ func (e *Engine) createPeerConn(pubKey string, allowedIPs string) (*peer.Conn, e
 		PreSharedKey: e.config.PreSharedKey,
 	}
 
+	if e.config.RosenpassEnabled {
+		lk := []byte(e.config.WgPrivateKey.PublicKey().String())
+		rk := []byte(wgConfig.RemoteKey)
+		var keyInput []byte
+		if string(lk) > string(rk) {
+			//nolint:gocritic
+			keyInput = append(lk[:16], rk[:16]...)
+		} else {
+			//nolint:gocritic
+			keyInput = append(rk[:16], lk[:16]...)
+		}
+
+		key, err := wgtypes.NewKey(keyInput)
+		if err != nil {
+			return nil, err
+		}
+
+		wgConfig.PreSharedKey = &key
+	}
+
 	// randomize connection timeout
 	timeout := time.Duration(rand.Intn(PeerConnectionTimeoutMax-PeerConnectionTimeoutMin)+PeerConnectionTimeoutMin) * time.Millisecond
 	config := peer.ConnConfig{
@@ -811,6 +850,8 @@ func (e *Engine) createPeerConn(pubKey string, allowedIPs string) (*peer.Conn, e
 		LocalWgPort:          e.config.WgPort,
 		NATExternalIPs:       e.parseNATExternalIPMappings(),
 		UserspaceBind:        e.wgInterface.IsUserspaceBind(),
+		RosenpassPubKey:      e.getRosenpassPubKey(),
+		RosenpassAddr:        e.getRosenpassAddr(),
 	}
 
 	peerConn, err := peer.NewConn(config, e.statusRecorder, e.wgProxyFactory, e.mobileDep.TunAdapter, e.mobileDep.IFaceDiscover)
@@ -842,6 +883,12 @@ func (e *Engine) createPeerConn(pubKey string, allowedIPs string) (*peer.Conn, e
 		return sendSignal(message, e.signal)
 	})
 
+	if e.rpManager != nil {
+
+		peerConn.SetOnConnected(e.rpManager.OnConnected)
+		peerConn.SetOnDisconnected(e.rpManager.OnDisconnected)
+	}
+
 	return peerConn, nil
 }
 
@@ -867,13 +914,21 @@ func (e *Engine) receiveSignalEvents() {
 
 				conn.RegisterProtoSupportMeta(msg.Body.GetFeaturesSupported())
 
+				var rosenpassPubKey []byte
+				rosenpassAddr := ""
+				if msg.GetBody().GetRosenpassConfig() != nil {
+					rosenpassPubKey = msg.GetBody().GetRosenpassConfig().GetRosenpassPubKey()
+					rosenpassAddr = msg.GetBody().GetRosenpassConfig().GetRosenpassServerAddr()
+				}
 				conn.OnRemoteOffer(peer.OfferAnswer{
 					IceCredentials: peer.IceCredentials{
 						UFrag: remoteCred.UFrag,
 						Pwd:   remoteCred.Pwd,
 					},
-					WgListenPort: int(msg.GetBody().GetWgListenPort()),
-					Version:      msg.GetBody().GetNetBirdVersion(),
+					WgListenPort:    int(msg.GetBody().GetWgListenPort()),
+					Version:         msg.GetBody().GetNetBirdVersion(),
+					RosenpassPubKey: rosenpassPubKey,
+					RosenpassAddr:   rosenpassAddr,
 				})
 			case sProto.Body_ANSWER:
 				remoteCred, err := signal.UnMarshalCredential(msg)
@@ -881,15 +936,23 @@ func (e *Engine) receiveSignalEvents() {
 					return err
 				}
 
-				conn.RegisterProtoSupportMeta(msg.Body.GetFeaturesSupported())
+				conn.RegisterProtoSupportMeta(msg.GetBody().GetFeaturesSupported())
 
+				var rosenpassPubKey []byte
+				rosenpassAddr := ""
+				if msg.GetBody().GetRosenpassConfig() != nil {
+					rosenpassPubKey = msg.GetBody().GetRosenpassConfig().GetRosenpassPubKey()
+					rosenpassAddr = msg.GetBody().GetRosenpassConfig().GetRosenpassServerAddr()
+				}
 				conn.OnRemoteAnswer(peer.OfferAnswer{
 					IceCredentials: peer.IceCredentials{
 						UFrag: remoteCred.UFrag,
 						Pwd:   remoteCred.Pwd,
 					},
-					WgListenPort: int(msg.GetBody().GetWgListenPort()),
-					Version:      msg.GetBody().GetNetBirdVersion(),
+					WgListenPort:    int(msg.GetBody().GetWgListenPort()),
+					Version:         msg.GetBody().GetNetBirdVersion(),
+					RosenpassPubKey: rosenpassPubKey,
+					RosenpassAddr:   rosenpassAddr,
 				})
 			case sProto.Body_CANDIDATE:
 				candidate, err := ice.UnmarshalCandidate(msg.GetBody().Payload)
@@ -1000,6 +1063,10 @@ func (e *Engine) close() {
 			log.Warnf("failed to reset firewall: %s", err)
 		}
 	}
+
+	if e.rpManager != nil {
+		_ = e.rpManager.Close()
+	}
 }
 
 func (e *Engine) readInitialSettings() ([]*route.Route, *nbdns.Config, error) {
@@ -1094,3 +1161,17 @@ func findIPFromInterface(iface *net.Interface) (net.IP, error) {
 	}
 	return nil, fmt.Errorf("interface %s don't have an ipv4 address", iface.Name)
 }
+
+func (e *Engine) getRosenpassPubKey() []byte {
+	if e.rpManager != nil {
+		return e.rpManager.GetPubKey()
+	}
+	return nil
+}
+
+func (e *Engine) getRosenpassAddr() string {
+	if e.rpManager != nil {
+		return e.rpManager.GetAddress().String()
+	}
+	return ""
+}

client/internal/peer/conn.go

@@ -67,6 +67,11 @@ type ConnConfig struct {
 
 	// UsesBind indicates whether the WireGuard interface is userspace and uses bind.ICEBind
 	UserspaceBind bool
+
+	// RosenpassPubKey is this peer's Rosenpass public key
+	RosenpassPubKey []byte
+	// RosenpassPubKey is this peer's RosenpassAddr server address (IP:port)
+	RosenpassAddr string
 }
 
 // OfferAnswer represents a session establishment offer or answer
@@ -79,6 +84,12 @@ type OfferAnswer struct {
 
 	// Version of NetBird Agent
 	Version string
+	// RosenpassPubKey is the Rosenpass public key of the remote peer when receiving this message
+	// This value is the local Rosenpass server public key when sending the message
+	RosenpassPubKey []byte
+	// RosenpassAddr is the Rosenpass server address (IP:port) of the remote peer when receiving this message
+	// This value is the local Rosenpass server address when sending the message
+	RosenpassAddr string
 }
 
 // IceCredentials ICE protocol credentials struct
@@ -97,6 +108,8 @@ type Conn struct {
 	signalOffer       func(OfferAnswer) error
 	signalAnswer      func(OfferAnswer) error
 	sendSignalMessage func(message *sProto.Message) error
+	onConnected       func(remoteWireGuardKey string, remoteRosenpassPubKey []byte, wireGuardIP string, remoteRosenpassAddr string)
+	onDisconnected    func(remotePeer string, wgIP string)
 
 	// remoteOffersCh is a channel used to wait for remote credentials to proceed with the connection
 	remoteOffersCh chan OfferAnswer
@@ -335,7 +348,8 @@ func (conn *Conn) Open() error {
 		remoteWgPort = remoteOfferAnswer.WgListenPort
 	}
 	// the ice connection has been established successfully so we are ready to start the proxy
-	remoteAddr, err := conn.configureConnection(remoteConn, remoteWgPort)
+	remoteAddr, err := conn.configureConnection(remoteConn, remoteWgPort, remoteOfferAnswer.RosenpassPubKey,
+		remoteOfferAnswer.RosenpassAddr)
 	if err != nil {
 		return err
 	}
@@ -358,7 +372,7 @@ func isRelayCandidate(candidate ice.Candidate) bool {
 }
 
 // configureConnection starts proxying traffic from/to local Wireguard and sets connection status to StatusConnected
-func (conn *Conn) configureConnection(remoteConn net.Conn, remoteWgPort int) (net.Addr, error) {
+func (conn *Conn) configureConnection(remoteConn net.Conn, remoteWgPort int, remoteRosenpassPubKey []byte, remoteRosenpassAddr string) (net.Addr, error) {
 	conn.mu.Lock()
 	defer conn.mu.Unlock()
 
@@ -376,7 +390,7 @@ func (conn *Conn) configureConnection(remoteConn net.Conn, remoteWgPort int) (ne
 			return nil, err
 		}
 	} else {
-		// To support old version's with direct mode we attempt to punch an additional role with the remote wireguard port
+		// To support old version's with direct mode we attempt to punch an additional role with the remote WireGuard port
 		go conn.punchRemoteWGPort(pair, remoteWgPort)
 		endpoint = remoteConn.RemoteAddr()
 	}
@@ -410,6 +424,15 @@ func (conn *Conn) configureConnection(remoteConn net.Conn, remoteWgPort int) (ne
 		log.Warnf("unable to save peer's state, got error: %v", err)
 	}
 
+	_, ipNet, err := net.ParseCIDR(conn.config.WgConfig.AllowedIps)
+	if err != nil {
+		return nil, err
+	}
+
+	if conn.onConnected != nil {
+		conn.onConnected(conn.config.Key, remoteRosenpassPubKey, ipNet.IP.String(), remoteRosenpassAddr)
+	}
+
 	return endpoint, nil
 }
 
@@ -460,6 +483,10 @@ func (conn *Conn) cleanup() error {
 		conn.notifyDisconnected = nil
 	}
 
+	if conn.status == StatusConnected && conn.onDisconnected != nil {
+		conn.onDisconnected(conn.config.WgConfig.RemoteKey, conn.config.WgConfig.AllowedIps)
+	}
+
 	conn.status = StatusDisconnected
 
 	peerState := State{
@@ -489,6 +516,16 @@ func (conn *Conn) SetSignalOffer(handler func(offer OfferAnswer) error) {
 	conn.signalOffer = handler
 }
 
+// SetOnConnected sets a handler function to be triggered by Conn when a new connection to a remote peer established
+func (conn *Conn) SetOnConnected(handler func(remoteWireGuardKey string, remoteRosenpassPubKey []byte, wireGuardIP string, remoteRosenpassAddr string)) {
+	conn.onConnected = handler
+}
+
+// SetOnDisconnected sets a handler function to be triggered by Conn when a connection to a remote disconnected
+func (conn *Conn) SetOnDisconnected(handler func(remotePeer string, wgIP string)) {
+	conn.onDisconnected = handler
+}
+
 // SetSignalAnswer sets a handler function to be triggered by Conn when a new connection answer has to be signalled to the remote peer
 func (conn *Conn) SetSignalAnswer(handler func(answer OfferAnswer) error) {
 	conn.signalAnswer = handler
@@ -543,9 +580,11 @@ func (conn *Conn) sendAnswer() error {
 
 	log.Debugf("sending answer to %s", conn.config.Key)
 	err = conn.signalAnswer(OfferAnswer{
-		IceCredentials: IceCredentials{localUFrag, localPwd},
-		WgListenPort:   conn.config.LocalWgPort,
-		Version:        version.NetbirdVersion(),
+		IceCredentials:  IceCredentials{localUFrag, localPwd},
+		WgListenPort:    conn.config.LocalWgPort,
+		Version:         version.NetbirdVersion(),
+		RosenpassPubKey: conn.config.RosenpassPubKey,
+		RosenpassAddr:   conn.config.RosenpassAddr,
 	})
 	if err != nil {
 		return err
@@ -564,9 +603,11 @@ func (conn *Conn) sendOffer() error {
 		return err
 	}
 	err = conn.signalOffer(OfferAnswer{
-		IceCredentials: IceCredentials{localUFrag, localPwd},
-		WgListenPort:   conn.config.LocalWgPort,
-		Version:        version.NetbirdVersion(),
+		IceCredentials:  IceCredentials{localUFrag, localPwd},
+		WgListenPort:    conn.config.LocalWgPort,
+		Version:         version.NetbirdVersion(),
+		RosenpassPubKey: conn.config.RosenpassPubKey,
+		RosenpassAddr:   conn.config.RosenpassAddr,
 	})
 	if err != nil {
 		return err

client/internal/rosenpass/manager.go

@@ -0,0 +1,204 @@
+package rosenpass
+
+import (
+	"bytes"
+	"crypto/sha256"
+	"encoding/hex"
+	"fmt"
+	"log/slog"
+	"net"
+	"os"
+	"strconv"
+	"strings"
+	"sync"
+
+	rp "cunicu.li/go-rosenpass"
+	log "github.com/sirupsen/logrus"
+	"golang.zx2c4.com/wireguard/wgctrl/wgtypes"
+)
+
+func hashRosenpassKey(key []byte) string {
+	hasher := sha256.New()
+	hasher.Write(key)
+	return hex.EncodeToString(hasher.Sum(nil))
+}
+
+type Manager struct {
+	ifaceName    string
+	spk          []byte
+	ssk          []byte
+	rpKeyHash    string
+	preSharedKey *[32]byte
+	rpPeerIDs    map[string]*rp.PeerID
+	rpWgHandler  *NetbirdHandler
+	server       *rp.Server
+	lock         sync.Mutex
+	port         int
+}
+
+// NewManager creates a new Rosenpass manager
+func NewManager(preSharedKey *wgtypes.Key, wgIfaceName string) (*Manager, error) {
+	public, secret, err := rp.GenerateKeyPair()
+	if err != nil {
+		return nil, err
+	}
+
+	rpKeyHash := hashRosenpassKey(public)
+	log.Debugf("generated new rosenpass key pair with public key %s", rpKeyHash)
+	return &Manager{ifaceName: wgIfaceName, rpKeyHash: rpKeyHash, spk: public, ssk: secret, preSharedKey: (*[32]byte)(preSharedKey), rpPeerIDs: make(map[string]*rp.PeerID), lock: sync.Mutex{}}, nil
+}
+
+func (m *Manager) GetPubKey() []byte {
+	return m.spk
+}
+
+// GetAddress returns the address of the Rosenpass server
+func (m *Manager) GetAddress() *net.UDPAddr {
+	return &net.UDPAddr{Port: m.port}
+}
+
+// addPeer adds a new peer to the Rosenpass server
+func (m *Manager) addPeer(rosenpassPubKey []byte, rosenpassAddr string, wireGuardIP string, wireGuardPubKey string) error {
+	var err error
+	pcfg := rp.PeerConfig{PublicKey: rosenpassPubKey}
+	if m.preSharedKey != nil {
+		pcfg.PresharedKey = *m.preSharedKey
+	}
+	if bytes.Compare(m.spk, rosenpassPubKey) == 1 {
+		_, strPort, err := net.SplitHostPort(rosenpassAddr)
+		if err != nil {
+			return fmt.Errorf("failed to parse rosenpass address: %w", err)
+		}
+		peerAddr := fmt.Sprintf("%s:%s", wireGuardIP, strPort)
+		if pcfg.Endpoint, err = net.ResolveUDPAddr("udp", peerAddr); err != nil {
+			return fmt.Errorf("failed to resolve peer endpoint address: %w", err)
+		}
+	}
+	peerID, err := m.server.AddPeer(pcfg)
+	if err != nil {
+		return err
+	}
+
+	key, err := wgtypes.ParseKey(wireGuardPubKey)
+	if err != nil {
+		return err
+	}
+	m.rpWgHandler.AddPeer(peerID, m.ifaceName, rp.Key(key))
+	m.rpPeerIDs[wireGuardPubKey] = &peerID
+	return nil
+}
+
+// removePeer removes a peer from the Rosenpass server
+func (m *Manager) removePeer(wireGuardPubKey string) error {
+	err := m.server.RemovePeer(*m.rpPeerIDs[wireGuardPubKey])
+	if err != nil {
+		return err
+	}
+	m.rpWgHandler.RemovePeer(*m.rpPeerIDs[wireGuardPubKey])
+	return nil
+}
+
+func (m *Manager) generateConfig() (rp.Config, error) {
+	opts := &slog.HandlerOptions{
+		Level: slog.LevelDebug,
+	}
+	logger := slog.New(slog.NewTextHandler(os.Stdout, opts))
+	cfg := rp.Config{Logger: logger}
+
+	cfg.PublicKey = m.spk
+	cfg.SecretKey = m.ssk
+
+	cfg.Peers = []rp.PeerConfig{}
+	m.rpWgHandler, _ = NewNetbirdHandler(m.preSharedKey, m.ifaceName)
+
+	cfg.Handlers = []rp.Handler{m.rpWgHandler}
+
+	port, err := findRandomAvailableUDPPort()
+	if err != nil {
+		log.Errorf("could not determine a random port for rosenpass server. Error: %s", err)
+		return rp.Config{}, err
+	}
+
+	m.port = port
+
+	cfg.ListenAddrs = []*net.UDPAddr{m.GetAddress()}
+
+	return cfg, nil
+}
+
+func (m *Manager) OnDisconnected(peerKey string, wgIP string) {
+	m.lock.Lock()
+	defer m.lock.Unlock()
+
+	if _, ok := m.rpPeerIDs[peerKey]; !ok {
+		// if we didn't have this peer yet, just skip
+		return
+	}
+
+	err := m.removePeer(peerKey)
+	if err != nil {
+		log.Error("failed to remove rosenpass peer", err)
+	}
+
+	delete(m.rpPeerIDs, peerKey)
+}
+
+// Run starts the Rosenpass server
+func (m *Manager) Run() error {
+	conf, err := m.generateConfig()
+	if err != nil {
+		return err
+	}
+
+	m.server, err = rp.NewUDPServer(conf)
+	if err != nil {
+		return err
+	}
+
+	log.Infof("starting rosenpass server on port %d", m.port)
+
+	return m.server.Run()
+}
+
+// Close closes the Rosenpass server
+func (m *Manager) Close() error {
+	if m.server != nil {
+		err := m.server.Close()
+		if err != nil {
+			log.Errorf("failed closing local rosenpass server")
+		}
+		m.server = nil
+	}
+	return nil
+}
+
+// OnConnected is a handler function that is triggered when a connection to a remote peer establishes
+func (m *Manager) OnConnected(remoteWireGuardKey string, remoteRosenpassPubKey []byte, wireGuardIP string, remoteRosenpassAddr string) {
+	m.lock.Lock()
+	defer m.lock.Unlock()
+
+	if remoteRosenpassPubKey == nil {
+		log.Warnf("remote peer with public key %s does not support rosenpass", remoteWireGuardKey)
+		return
+	}
+
+	rpKeyHash := hashRosenpassKey(remoteRosenpassPubKey)
+	log.Debugf("received remote rosenpass key %s, my key %s", rpKeyHash, m.rpKeyHash)
+
+	err := m.addPeer(remoteRosenpassPubKey, remoteRosenpassAddr, wireGuardIP, remoteWireGuardKey)
+	if err != nil {
+		log.Errorf("failed to add rosenpass peer: %s", err)
+		return
+	}
+}
+
+func findRandomAvailableUDPPort() (int, error) {
+	conn, err := net.ListenUDP("udp", &net.UDPAddr{IP: net.IPv4zero, Port: 0})
+	if err != nil {
+		return 0, fmt.Errorf("could not find an available UDP port: %w", err)
+	}
+	defer conn.Close()
+
+	splitAddress := strings.Split(conn.LocalAddr().String(), ":")
+	return strconv.Atoi(splitAddress[len(splitAddress)-1])
+}

client/internal/rosenpass/netbird_handler.go

@@ -0,0 +1,126 @@
+package rosenpass
+
+import (
+	"fmt"
+	"log/slog"
+
+	rp "cunicu.li/go-rosenpass"
+	log "github.com/sirupsen/logrus"
+
+	"golang.zx2c4.com/wireguard/wgctrl"
+	"golang.zx2c4.com/wireguard/wgctrl/wgtypes"
+)
+
+type wireGuardPeer struct {
+	Interface string
+	PublicKey rp.Key
+}
+
+type NetbirdHandler struct {
+	ifaceName    string
+	client       *wgctrl.Client
+	peers        map[rp.PeerID]wireGuardPeer
+	presharedKey [32]byte
+}
+
+func NewNetbirdHandler(preSharedKey *[32]byte, wgIfaceName string) (hdlr *NetbirdHandler, err error) {
+	hdlr = &NetbirdHandler{
+		ifaceName: wgIfaceName,
+		peers:     map[rp.PeerID]wireGuardPeer{},
+	}
+
+	if preSharedKey != nil {
+		hdlr.presharedKey = *preSharedKey
+	}
+
+	if hdlr.client, err = wgctrl.New(); err != nil {
+		return nil, fmt.Errorf("failed to creat WireGuard client: %w", err)
+	}
+
+	return hdlr, nil
+}
+
+func (h *NetbirdHandler) AddPeer(pid rp.PeerID, intf string, pk rp.Key) {
+	h.peers[pid] = wireGuardPeer{
+		Interface: intf,
+		PublicKey: pk,
+	}
+}
+
+func (h *NetbirdHandler) RemovePeer(pid rp.PeerID) {
+	delete(h.peers, pid)
+}
+
+func (h *NetbirdHandler) HandshakeCompleted(pid rp.PeerID, key rp.Key) {
+	log.Debug("Handshake complete")
+	h.outputKey(rp.KeyOutputReasonStale, pid, key)
+}
+
+func (h *NetbirdHandler) HandshakeExpired(pid rp.PeerID) {
+	key, _ := rp.GeneratePresharedKey()
+	log.Debug("Handshake expired")
+	h.outputKey(rp.KeyOutputReasonStale, pid, key)
+}
+
+func (h *NetbirdHandler) outputKey(_ rp.KeyOutputReason, pid rp.PeerID, psk rp.Key) {
+	wg, ok := h.peers[pid]
+	if !ok {
+		return
+	}
+
+	device, err := h.client.Device(h.ifaceName)
+	if err != nil {
+		log.Errorf("Failed to get WireGuard device: %v", err)
+		return
+	}
+	config := []wgtypes.PeerConfig{
+		{
+			UpdateOnly:   true,
+			PublicKey:    wgtypes.Key(wg.PublicKey),
+			PresharedKey: (*wgtypes.Key)(&psk),
+		},
+	}
+	for _, peer := range device.Peers {
+		if peer.PublicKey == wgtypes.Key(wg.PublicKey) {
+			if publicKeyEmpty(peer.PresharedKey) || peer.PresharedKey == h.presharedKey {
+				log.Debugf("Restart wireguard connection to peer %s", peer.PublicKey)
+				config = []wgtypes.PeerConfig{
+					{
+						PublicKey:    wgtypes.Key(wg.PublicKey),
+						PresharedKey: (*wgtypes.Key)(&psk),
+						Endpoint:     peer.Endpoint,
+						AllowedIPs:   peer.AllowedIPs,
+					},
+				}
+				err = h.client.ConfigureDevice(wg.Interface, wgtypes.Config{
+					Peers: []wgtypes.PeerConfig{
+						{
+							Remove:    true,
+							PublicKey: wgtypes.Key(wg.PublicKey),
+						},
+					},
+				})
+				if err != nil {
+					slog.Debug("Failed to remove peer")
+					return
+				}
+			}
+
+		}
+	}
+
+	if err = h.client.ConfigureDevice(wg.Interface, wgtypes.Config{
+		Peers: config,
+	}); err != nil {
+		log.Errorf("Failed to apply rosenpass key: %v", err)
+	}
+}
+
+func publicKeyEmpty(key wgtypes.Key) bool {
+	for _, b := range key {
+		if b != 0 {
+			return false
+		}
+	}
+	return true
+}