Method sendTSMPPing

wgengine/userspace.go:1439–1484

(ip netip.Addr, peer tailcfg.NodeView, res *ipnstate.PingResult, cb func(*ipnstate.PingResult))

}

func (e *userspaceEngine) sendTSMPPing(ip netip.Addr, peer tailcfg.NodeView, res *ipnstate.PingResult, cb func(*ipnstate.PingResult)) {
	srcIP, err := e.mySelfIPMatchingFamily(ip)
	if err != nil {
		res.Err = err.Error()
		cb(res)
		return
	}
	var iph packet.Header
	if srcIP.Is4() {
		iph = packet.IP4Header{
			IPProto: ipproto.TSMP,
			Src:     srcIP,
			Dst:     ip,
		}
	} else {
		iph = packet.IP6Header{
			IPProto: ipproto.TSMP,
			Src:     srcIP,
			Dst:     ip,
		}
	}

	var data [8]byte
	crand.Read(data[:])

	expireTimer := time.AfterFunc(10*time.Second, func() {
		e.setTSMPPongCallback(data, nil)
	})
	t0 := time.Now()
	e.setTSMPPongCallback(data, func(pong packet.TSMPPongReply) {
		expireTimer.Stop()
		d := time.Since(t0)
		res.LatencySeconds = d.Seconds()
		res.NodeIP = ip.String()
		res.NodeName = peer.ComputedName()
		res.PeerAPIPort = pong.PeerAPIPort
		cb(res)
	})

	var tsmpPayload [9]byte
	tsmpPayload[0] = byte(packet.TSMPTypePing)
	copy(tsmpPayload[1:], data[:])

	tsmpPing := packet.Generate(iph, tsmpPayload[:])
	e.tundev.InjectOutbound(tsmpPing)
}

func (e *userspaceEngine) sendTSMPDiscoAdvertisement(ip netip.Addr) {
	srcIP, err := e.mySelfIPMatchingFamily(ip)