all: pass log IDs as the proper type rather than strings

This change focuses on the backend log ID, which is the mostly commonly
used in the client.  Tests which don't seem to make use of the log ID
just use the zero value.

Signed-off-by: Will Norris <will@tailscale.com>

ipn/ipnlocal/local.go

@@ -63,6 +63,7 @@ import (
 	"tailscale.com/types/empty"
 	"tailscale.com/types/key"
 	"tailscale.com/types/logger"
+	"tailscale.com/types/logid"
 	"tailscale.com/types/netmap"
 	"tailscale.com/types/persist"
 	"tailscale.com/types/preftype"
@@ -139,7 +140,7 @@ type LocalBackend struct {
 	pm                    *profileManager
 	store                 ipn.StateStore
 	dialer                *tsdial.Dialer // non-nil
-	backendLogID          string
+	backendLogID          logid.PublicID
 	unregisterLinkMon     func()
 	unregisterHealthWatch func()
 	portpoll              *portlist.Poller // may be nil
@@ -265,7 +266,7 @@ type clientGen func(controlclient.Options) (controlclient.Client, error)
 // but is not actually running.
 //
 // If dialer is nil, a new one is made.
-func NewLocalBackend(logf logger.Logf, logid string, store ipn.StateStore, dialer *tsdial.Dialer, e wgengine.Engine, loginFlags controlclient.LoginFlags) (*LocalBackend, error) {
+func NewLocalBackend(logf logger.Logf, logID logid.PublicID, store ipn.StateStore, dialer *tsdial.Dialer, e wgengine.Engine, loginFlags controlclient.LoginFlags) (*LocalBackend, error) {
 	if e == nil {
 		panic("ipn.NewLocalBackend: engine must not be nil")
 	}
@@ -300,7 +301,7 @@ func NewLocalBackend(logf logger.Logf, logid string, store ipn.StateStore, diale
 		pm:             pm,
 		store:          pm.Store(),
 		dialer:         dialer,
-		backendLogID:   logid,
+		backendLogID:   logID,
 		state:          ipn.NoState,
 		portpoll:       portpoll,
 		em:             newExpiryManager(logf),
@@ -310,7 +311,7 @@ func NewLocalBackend(logf logger.Logf, logid string, store ipn.StateStore, diale
 
 	// for now, only log sockstats on unstable builds
 	if version.IsUnstableBuild() {
-		b.sockstatLogger, err = sockstatlog.NewLogger(logpolicy.LogsDir(logf), logf, logid)
+		b.sockstatLogger, err = sockstatlog.NewLogger(logpolicy.LogsDir(logf), logf, logID)
 		if err != nil {
 			log.Printf("error setting up sockstat logger: %v", err)
 		}
@@ -1294,7 +1295,7 @@ func (b *LocalBackend) Start(opts ipn.Options) error {
 	}
 
 	hostinfo := hostinfo.New()
-	hostinfo.BackendLogID = b.backendLogID
+	hostinfo.BackendLogID = b.backendLogID.String()
 	hostinfo.FrontendLogID = opts.FrontendLogID
 	hostinfo.Userspace.Set(wgengine.IsNetstack(b.e))
 	hostinfo.UserspaceRouter.Set(wgengine.IsNetstackRouter(b.e))
@@ -1448,7 +1449,7 @@ func (b *LocalBackend) Start(opts ipn.Options) error {
 
 	b.e.SetNetInfoCallback(b.setNetInfo)
 
-	blid := b.backendLogID
+	blid := b.backendLogID.String()
 	b.logf("Backend: logs: be:%v fe:%v", blid, opts.FrontendLogID)
 	b.send(ipn.Notify{BackendLogID: &blid})
 	b.send(ipn.Notify{Prefs: &prefs})

ipn/ipnlocal/local_test.go

@@ -23,6 +23,7 @@ import (
 	"tailscale.com/tstest"
 	"tailscale.com/types/key"
 	"tailscale.com/types/logger"
+	"tailscale.com/types/logid"
 	"tailscale.com/types/netmap"
 	"tailscale.com/wgengine"
 	"tailscale.com/wgengine/filter"
@@ -506,7 +507,7 @@ func TestLazyMachineKeyGeneration(t *testing.T) {
 		t.Fatalf("NewFakeUserspaceEngine: %v", err)
 	}
 	t.Cleanup(eng.Close)
-	lb, err := NewLocalBackend(logf, "logid", store, nil, eng, 0)
+	lb, err := NewLocalBackend(logf, logid.PublicID{}, store, nil, eng, 0)
 	if err != nil {
 		t.Fatalf("NewLocalBackend: %v", err)
 	}
@@ -770,7 +771,7 @@ func TestStatusWithoutPeers(t *testing.T) {
 	}
 	t.Cleanup(e.Close)
 
-	b, err := NewLocalBackend(logf, "logid", store, nil, e, 0)
+	b, err := NewLocalBackend(logf, logid.PublicID{}, store, nil, e, 0)
 	if err != nil {
 		t.Fatalf("NewLocalBackend: %v", err)
 	}

ipn/ipnlocal/loglines_test.go

@@ -54,7 +54,7 @@ func TestLocalLogLines(t *testing.T) {
 	}
 	t.Cleanup(e.Close)
 
-	lb, err := NewLocalBackend(logf, idA.String(), store, nil, e, 0)
+	lb, err := NewLocalBackend(logf, idA, store, nil, e, 0)
 	if err != nil {
 		t.Fatal(err)
 	}

ipn/ipnlocal/state_test.go

@@ -21,6 +21,7 @@ import (
 	"tailscale.com/types/empty"
 	"tailscale.com/types/key"
 	"tailscale.com/types/logger"
+	"tailscale.com/types/logid"
 	"tailscale.com/types/netmap"
 	"tailscale.com/types/persist"
 	"tailscale.com/wgengine"
@@ -303,7 +304,7 @@ func TestStateMachine(t *testing.T) {
 	}
 	t.Cleanup(e.Close)
 
-	b, err := NewLocalBackend(logf, "logid", store, nil, e, 0)
+	b, err := NewLocalBackend(logf, logid.PublicID{}, store, nil, e, 0)
 	if err != nil {
 		t.Fatalf("NewLocalBackend: %v", err)
 	}
@@ -946,7 +947,7 @@ func TestEditPrefsHasNoKeys(t *testing.T) {
 	}
 	t.Cleanup(e.Close)
 
-	b, err := NewLocalBackend(logf, "logid", new(mem.Store), nil, e, 0)
+	b, err := NewLocalBackend(logf, logid.PublicID{}, new(mem.Store), nil, e, 0)
 	if err != nil {
 		t.Fatalf("NewLocalBackend: %v", err)
 	}
@@ -1025,7 +1026,7 @@ func TestWGEngineStatusRace(t *testing.T) {
 	eng, err := wgengine.NewFakeUserspaceEngine(logf, 0)
 	c.Assert(err, qt.IsNil)
 	t.Cleanup(eng.Close)
-	b, err := NewLocalBackend(logf, "logid", new(mem.Store), nil, eng, 0)
+	b, err := NewLocalBackend(logf, logid.PublicID{}, new(mem.Store), nil, eng, 0)
 	c.Assert(err, qt.IsNil)
 
 	var cc *mockControl