controlclient: persist node key after login, don't wait for netmaprajsingh/persist-nodekey-before-register

sendStatus only included Persist in the Status when a netmap was
available (nm != nil && loggedIn && inMapPoll). This meant the node
key was not written to the state store until the first map response
arrived. If the process was killed after a successful registration
but before the first netmap, the key was lost and a fresh one
generated on restart.

Decouple persist from the netmap gate so it flows to the state store
as soon as login succeeds.

Fixes #19149

Signed-off-by: Raj Singh <raj@tailscale.com>

3 files changed, 3 insertions, 34 deletions

diff --git a/control/controlclient/auto.go b/control/controlclient/auto.go
index b087e1444..d7da21932 100644
--- a/control/controlclient/auto.go
+++ b/control/controlclient/auto.go
@@ -625,9 +625,10 @@ func (c *Auto) sendStatus(who string, err error, url string, nm *netmap.NetworkM
 	c.logf("[v1] sendStatus: %s: loggedIn=%v inMapPoll=%v", who, loggedIn, inMapPoll)
 
 	var p persist.PersistView
-	if nm != nil && loggedIn && inMapPoll {
+	if loggedIn {
 		p = c.direct.GetPersist()
-	} else {
+	}
+	if !(nm != nil && loggedIn && inMapPoll) {
 		// don't send netmap status, as it's misleading when we're
 		// not logged in.
 		nm = nil
diff --git a/control/controlclient/direct.go b/control/controlclient/direct.go
index cbbf2bdfe..3b4e6ba9b 100644
--- a/control/controlclient/direct.go
+++ b/control/controlclient/direct.go
@@ -79,7 +79,6 @@ type Direct struct {
 	autoUpdatePub     *eventbus.Publisher[AutoUpdate]
 	controlTimePub    *eventbus.Publisher[ControlTime]
 	getMachinePrivKey func() (key.MachinePrivate, error)
-	persistState      func(persist.PersistView) // or nil; called before RegisterRequest to persist new node key
 	debugFlags        []string
 	pinger            Pinger
 	popBrowser        func(url string)    // or nil
@@ -177,12 +176,6 @@ type Options struct {
 	// attempted. It is used to allow the client to clean up any resources or complete any
 	// tasks that are dependent on a live client.
 	Shutdown func()
-
-	// PersistState, if non-nil, is called with an updated Persist after
-	// generating a new node key but before sending the RegisterRequest.
-	// This allows the caller to write the key to durable storage so that
-	// a crash during registration doesn't lose the key.
-	PersistState func(persist.PersistView)
 }
 
 // ControlDialPlanner is the interface optionally supplied when creating a
@@ -338,7 +331,6 @@ func NewDirect(opts Options) (*Direct, error) {
 		dialer:            opts.Dialer,
 		dnsCache:          dnsCache,
 		dialPlan:          opts.DialPlan,
-		persistState:      opts.PersistState,
 	}
 	c.discoPubKey = opts.DiscoPublicKey
 	c.closedCtx, c.closeCtx = context.WithCancel(context.Background())
@@ -665,14 +657,6 @@ func (c *Direct) doLogin(ctx context.Context, opt loginOpt) (mustRegen bool, new
 		persist.NetworkLockKey = key.NewNLPrivate()
 	}
 
-	// Persist the new key before the RegisterRequest so a crash
-	// mid-HTTP doesn't lose it.
-	if c.persistState != nil && !tryingNewKey.IsZero() && (persist.PrivateNodeKey.IsZero() || tryingNewKey.Public() != persist.PrivateNodeKey.Public()) {
-		preHTTPPersist := persist
-		preHTTPPersist.PrivateNodeKey = tryingNewKey
-		c.persistState(preHTTPPersist.View())
-	}
-
 	nlPub := persist.NetworkLockKey.Public()
 
 	if tryingNewKey.IsZero() {
diff --git a/ipn/ipnlocal/local.go b/ipn/ipnlocal/local.go
index 3d5fc12fa..edeb2967b 100644
--- a/ipn/ipnlocal/local.go
+++ b/ipn/ipnlocal/local.go
@@ -2639,7 +2639,6 @@ func (b *LocalBackend) startLocked(opts ipn.Options) error {
 	// but it won't take effect until the next Start.
 	cc, err := b.getNewControlClientFuncLocked()(controlclient.Options{
 		GetMachinePrivateKey: b.createGetMachinePrivateKeyFunc(),
-		PersistState:         b.createPersistStateFunc(),
 		Logf:                 logger.WithPrefix(b.logf, "control: "),
 		Persist:              *persistv,
 		ServerURL:            serverURL,
@@ -3641,21 +3640,6 @@ func (b *LocalBackend) createGetMachinePrivateKeyFunc() func() (key.MachinePriva
 	}
 }
 
-// createPersistStateFunc returns a function that writes an updated Persist
-// directly to the state store, bypassing setPrefsNoPermCheck to avoid
-// triggering hooks for state not yet confirmed by the control server.
-func (b *LocalBackend) createPersistStateFunc() func(persist.PersistView) {
-	return func(p persist.PersistView) {
-		b.mu.Lock()
-		defer b.mu.Unlock()
-		prefs := b.pm.CurrentPrefs().AsStruct()
-		prefs.Persist = p.AsStruct()
-		if err := b.pm.writePrefsToStore(b.pm.currentProfile.Key(), prefs.View()); err != nil {
-			b.logf("persist node key before register: %v", err)
-		}
-	}
-}
-
 // initMachineKeyLocked is called to initialize b.machinePrivKey.
 //
 // b.prefs must already be initialized.