Function TestConcurrencySafety

polyamide/device/device_test.go:245–324

TestConcurrencySafety does other things concurrently with tunnel use. It is intended to be used with the race detector to catch data races.

(t *testing.T)

// TestConcurrencySafety does other things concurrently with tunnel use.
// It is intended to be used with the race detector to catch data races.
func TestConcurrencySafety(t *testing.T) {
	pair := genTestPair(t, true)
	done := make(chan struct{})

	const warmupIters = 10
	var warmup sync.WaitGroup
	warmup.Add(warmupIters)
	go func() {
		// Send data continuously back and forth until we're done.
		// Note that we may continue to attempt to send data
		// even after done is closed.
		i := warmupIters
		for ping := Ping; ; ping = !ping {
			pair.Send(t, ping, done)
			select {
			case <-done:
				return
			default:
			}
			if i > 0 {
				warmup.Done()
				i--
			}
		}
	}()
	warmup.Wait()

	applyCfg := func(cfg string) {
		err := pair[0].dev.IpcSet(cfg)
		if err != nil {
			t.Fatal(err)
		}
	}

	// Change persistent_keepalive_interval concurrently with tunnel use.
	t.Run("persistentKeepaliveInterval", func(t *testing.T) {
		var pub NoisePublicKey
		for key := range pair[0].dev.peers.keyMap {
			pub = key
			break
		}
		cfg := uapiCfg(
			"public_key", hex.EncodeToString(pub[:]),
			"persistent_keepalive_interval", "1",
		)
		for i := 0; i < 1000; i++ {
			applyCfg(cfg)
		}
	})

	// Change private keys concurrently with tunnel use.
	t.Run("privateKey", func(t *testing.T) {
		bad := uapiCfg("private_key", "7777777777777777777777777777777777777777777777777777777777777777")
		good := uapiCfg("private_key", hex.EncodeToString(pair[0].dev.staticIdentity.privateKey[:]))
		// Set iters to a large number like 1000 to flush out data races quickly.
		// Don't leave it large. That can cause logical races
		// in which the handshake is interleaved with key changes
		// such that the private key appears to be unchanging but