Function TestUserspaceEnginePortReconfig

wgengine/userspace_test.go:255–332

(t *testing.T)

}

func TestUserspaceEnginePortReconfig(t *testing.T) {
	flakytest.Mark(t, "https://github.com/tailscale/tailscale/issues/2855")
	const defaultPort = 49983

	var knobs controlknobs.Knobs

	bus := eventbustest.NewBus(t)

	// Keep making a wgengine until we find an unused port
	var ue *userspaceEngine
	ht := health.NewTracker(bus)
	reg := new(usermetric.Registry)
	for range 100 {
		attempt := uint16(defaultPort + rand.Intn(1000))
		e, err := NewFakeUserspaceEngine(t.Logf, attempt, &knobs, ht, reg, bus)
		if err != nil {
			t.Fatal(err)
		}
		ue = e.(*userspaceEngine)
		if ue.magicConn.LocalPort() == attempt {
			break
		}
		ue.Close()
		ue = nil
	}
	if ue == nil {
		t.Fatal("could not create a wgengine with a specific port")
	}
	t.Cleanup(ue.Close)

	startingPort := ue.magicConn.LocalPort()
	nodeKey, err := key.ParseNodePublicUntyped(mem.S("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"))
	if err != nil {
		t.Fatal(err)
	}
	cfg := &wgcfg.Config{
		Peers: []wgcfg.Peer{
			{
				PublicKey: nodeKey,
				AllowedIPs: []netip.Prefix{
					netip.PrefixFrom(netaddr.IPv4(100, 100, 99, 1), 32),
				},
			},
		},
	}
	routerCfg := &router.Config{}
	if err := ue.Reconfig(cfg, routerCfg, &dns.Config{}); err != nil {
		t.Fatal(err)
	}
	if got := ue.magicConn.LocalPort(); got != startingPort {
		t.Errorf("no debug setting changed local port to %d from %d", got, startingPort)
	}

	knobs.RandomizeClientPort.Store(true)
	if err := ue.Reconfig(cfg, routerCfg, &dns.Config{}); err != nil {
		t.Fatal(err)
	}
	if got := ue.magicConn.LocalPort(); got == startingPort {