client/web: fix CSRF handler order in web UI

Fix the order of the CSRF handlers (HTTP plaintext context setting,
_then_ enforcement) in the construction of the web UI server. This
resolves false-positive "invalid Origin" 403 exceptions when attempting
to update settings in the web UI.

Add unit test to exercise the CSRF protection failure and success cases
for our web UI configuration.

Updates #14822
Updates #14872

Signed-off-by: Patrick O'Doherty <patrick@tailscale.com>

.github/workflows/golangci-lint.yml

@@ -33,7 +33,7 @@ jobs:
       - name: golangci-lint
         uses: golangci/golangci-lint-action@2e788936b09dd82dc280e845628a40d2ba6b204c # v6.3.1
         with:
-          version: v1.60
+          version: v1.64
 
           # Show only new issues if it's a pull request.
           only-new-issues: true

.github/workflows/test.yml

@@ -64,7 +64,6 @@ jobs:
       matrix:
         include:
           - goarch: amd64
-            coverflags: "-coverprofile=/tmp/coverage.out"
           - goarch: amd64
             buildflags: "-race"
             shard: '1/3'
@@ -119,15 +118,10 @@ jobs:
     - name: build test wrapper
       run: ./tool/go build -o /tmp/testwrapper ./cmd/testwrapper
     - name: test all
-      run: NOBASHDEBUG=true PATH=$PWD/tool:$PATH /tmp/testwrapper ${{matrix.coverflags}} ./... ${{matrix.buildflags}}
+      run: NOBASHDEBUG=true PATH=$PWD/tool:$PATH /tmp/testwrapper ./... ${{matrix.buildflags}}
       env:
         GOARCH: ${{ matrix.goarch }}
         TS_TEST_SHARD: ${{ matrix.shard }}
-    - name: Publish to coveralls.io
-      if: matrix.coverflags != '' # only publish results if we've tracked coverage
-      uses: shogo82148/actions-goveralls@v1
-      with:
-        path-to-profile: /tmp/coverage.out
     - name: bench all
       run: ./tool/go test ${{matrix.buildflags}} -bench=. -benchtime=1x -run=^$ $(for x in $(git grep -l "^func Benchmark" | xargs dirname | sort | uniq); do echo "./$x"; done)
       env:

Dockerfile

@@ -27,7 +27,7 @@
 #     $ docker exec tailscaled tailscale status
 
 
-FROM golang:1.23-alpine AS build-env
+FROM golang:1.24-alpine AS build-env
 
 WORKDIR /go/src/tailscale
 

appc/appconnector.go

@@ -289,9 +289,11 @@ func (e *AppConnector) updateDomains(domains []string) {
 				toRemove = append(toRemove, netip.PrefixFrom(a, a.BitLen()))
 			}
 		}
-		if err := e.routeAdvertiser.UnadvertiseRoute(toRemove...); err != nil {
-			e.logf("failed to unadvertise routes on domain removal: %v: %v: %v", slicesx.MapKeys(oldDomains), toRemove, err)
-		}
+		e.queue.Add(func() {
+			if err := e.routeAdvertiser.UnadvertiseRoute(toRemove...); err != nil {
+				e.logf("failed to unadvertise routes on domain removal: %v: %v: %v", slicesx.MapKeys(oldDomains), toRemove, err)
+			}
+		})
 	}
 
 	e.logf("handling domains: %v and wildcards: %v", slicesx.MapKeys(e.domains), e.wildcards)
@@ -310,11 +312,6 @@ func (e *AppConnector) updateRoutes(routes []netip.Prefix) {
 		return
 	}
 
-	if err := e.routeAdvertiser.AdvertiseRoute(routes...); err != nil {
-		e.logf("failed to advertise routes: %v: %v", routes, err)
-		return
-	}
-
 	var toRemove []netip.Prefix
 
 	// If we're storing routes and know e.controlRoutes is a good
@@ -338,9 +335,14 @@ nextRoute:
 		}
 	}
 
-	if err := e.routeAdvertiser.UnadvertiseRoute(toRemove...); err != nil {
-		e.logf("failed to unadvertise routes: %v: %v", toRemove, err)
-	}
+	e.queue.Add(func() {
+		if err := e.routeAdvertiser.AdvertiseRoute(routes...); err != nil {
+			e.logf("failed to advertise routes: %v: %v", routes, err)
+		}
+		if err := e.routeAdvertiser.UnadvertiseRoute(toRemove...); err != nil {
+			e.logf("failed to unadvertise routes: %v: %v", toRemove, err)
+		}
+	})
 
 	e.controlRoutes = routes
 	if err := e.storeRoutesLocked(); err != nil {

appc/appconnector_test.go

@@ -8,6 +8,7 @@ import (
 	"net/netip"
 	"reflect"
 	"slices"
+	"sync/atomic"
 	"testing"
 	"time"
 
@@ -86,6 +87,7 @@ func TestUpdateRoutes(t *testing.T) {
 
 		routes := []netip.Prefix{netip.MustParsePrefix("192.0.2.0/24"), netip.MustParsePrefix("192.0.0.1/32")}
 		a.updateRoutes(routes)
+		a.Wait(ctx)
 
 		slices.SortFunc(rc.Routes(), prefixCompare)
 		rc.SetRoutes(slices.Compact(rc.Routes()))
@@ -105,6 +107,7 @@ func TestUpdateRoutes(t *testing.T) {
 }
 
 func TestUpdateRoutesUnadvertisesContainedRoutes(t *testing.T) {
+	ctx := context.Background()
 	for _, shouldStore := range []bool{false, true} {
 		rc := &appctest.RouteCollector{}
 		var a *AppConnector
@@ -117,6 +120,7 @@ func TestUpdateRoutesUnadvertisesContainedRoutes(t *testing.T) {
 		rc.SetRoutes([]netip.Prefix{netip.MustParsePrefix("192.0.2.1/32")})
 		routes := []netip.Prefix{netip.MustParsePrefix("192.0.2.0/24")}
 		a.updateRoutes(routes)
+		a.Wait(ctx)
 
 		if !slices.EqualFunc(routes, rc.Routes(), prefixEqual) {
 			t.Fatalf("got %v, want %v", rc.Routes(), routes)
@@ -636,3 +640,57 @@ func TestMetricBucketsAreSorted(t *testing.T) {
 		t.Errorf("metricStoreRoutesNBuckets must be in order")
 	}
 }
+
+// TestUpdateRoutesDeadlock is a regression test for a deadlock in
+// LocalBackend<->AppConnector interaction. When using real LocalBackend as the
+// routeAdvertiser, calls to Advertise/UnadvertiseRoutes can end up calling
+// back into AppConnector via authReconfig. If everything is called
+// synchronously, this results in a deadlock on AppConnector.mu.
+func TestUpdateRoutesDeadlock(t *testing.T) {
+	ctx := context.Background()
+	rc := &appctest.RouteCollector{}
+	a := NewAppConnector(t.Logf, rc, &RouteInfo{}, fakeStoreRoutes)
+
+	advertiseCalled := new(atomic.Bool)
+	unadvertiseCalled := new(atomic.Bool)
+	rc.AdvertiseCallback = func() {
+		// Call something that requires a.mu to be held.
+		a.DomainRoutes()
+		advertiseCalled.Store(true)
+	}
+	rc.UnadvertiseCallback = func() {
+		// Call something that requires a.mu to be held.
+		a.DomainRoutes()
+		unadvertiseCalled.Store(true)
+	}
+
+	a.updateDomains([]string{"example.com"})
+	a.Wait(ctx)
+
+	// Trigger rc.AdveriseRoute.
+	a.updateRoutes(
+		[]netip.Prefix{
+			netip.MustParsePrefix("127.0.0.1/32"),
+			netip.MustParsePrefix("127.0.0.2/32"),
+		},
+	)
+	a.Wait(ctx)
+	// Trigger rc.UnadveriseRoute.
+	a.updateRoutes(
+		[]netip.Prefix{
+			netip.MustParsePrefix("127.0.0.1/32"),
+		},
+	)
+	a.Wait(ctx)
+
+	if !advertiseCalled.Load() {
+		t.Error("AdvertiseRoute was not called")
+	}
+	if !unadvertiseCalled.Load() {
+		t.Error("UnadvertiseRoute was not called")
+	}
+
+	if want := []netip.Prefix{netip.MustParsePrefix("127.0.0.1/32")}; !slices.Equal(slices.Compact(rc.Routes()), want) {
+		t.Fatalf("got %v, want %v", rc.Routes(), want)
+	}
+}

appc/appctest/appctest.go

@@ -11,12 +11,22 @@ import (
 
 // RouteCollector is a test helper that collects the list of routes advertised
 type RouteCollector struct {
+	// AdvertiseCallback (optional) is called synchronously from
+	// AdvertiseRoute.
+	AdvertiseCallback func()
+	// UnadvertiseCallback (optional) is called synchronously from
+	// UnadvertiseRoute.
+	UnadvertiseCallback func()
+
 	routes        []netip.Prefix
 	removedRoutes []netip.Prefix
 }
 
 func (rc *RouteCollector) AdvertiseRoute(pfx ...netip.Prefix) error {
 	rc.routes = append(rc.routes, pfx...)
+	if rc.AdvertiseCallback != nil {
+		rc.AdvertiseCallback()
+	}
 	return nil
 }
 
@@ -30,6 +40,9 @@ func (rc *RouteCollector) UnadvertiseRoute(toRemove ...netip.Prefix) error {
 			rc.removedRoutes = append(rc.removedRoutes, r)
 		}
 	}
+	if rc.UnadvertiseCallback != nil {
+		rc.UnadvertiseCallback()
+	}
 	return nil
 }
 

client/systray/systray.go

@@ -72,6 +72,11 @@ type Menu struct {
 	curProfile  ipn.LoginProfile
 	allProfiles []ipn.LoginProfile
 
+	// readonly is whether the systray app is running in read-only mode.
+	// This is set if LocalAPI returns a permission error,
+	// typically because the user needs to run `tailscale set --operator=$USER`.
+	readonly bool
+
 	bgCtx    context.Context // ctx for background tasks not involving menu item clicks
 	bgCancel context.CancelFunc
 
@@ -153,6 +158,8 @@ func (menu *Menu) updateState() {
 	defer menu.mu.Unlock()
 	menu.init()
 
+	menu.readonly = false
+
 	var err error
 	menu.status, err = menu.lc.Status(menu.bgCtx)
 	if err != nil {
@@ -160,6 +167,9 @@ func (menu *Menu) updateState() {
 	}
 	menu.curProfile, menu.allProfiles, err = menu.lc.ProfileStatus(menu.bgCtx)
 	if err != nil {
+		if local.IsAccessDeniedError(err) {
+			menu.readonly = true
+		}
 		log.Print(err)
 	}
 }
@@ -182,6 +192,15 @@ func (menu *Menu) rebuild() {
 
 	systray.ResetMenu()
 
+	if menu.readonly {
+		const readonlyMsg = "No permission to manage Tailscale.\nSee tailscale.com/s/cli-operator"
+		m := systray.AddMenuItem(readonlyMsg, "")
+		onClick(ctx, m, func(_ context.Context) {
+			webbrowser.Open("https://tailscale.com/s/cli-operator")
+		})
+		systray.AddSeparator()
+	}
+
 	menu.connect = systray.AddMenuItem("Connect", "")
 	menu.disconnect = systray.AddMenuItem("Disconnect", "")
 	menu.disconnect.Hide()
@@ -222,28 +241,35 @@ func (menu *Menu) rebuild() {
 		setAppIcon(disconnected)
 	}
 
+	if menu.readonly {
+		menu.connect.Disable()
+		menu.disconnect.Disable()
+	}
+
 	account := "Account"
 	if pt := profileTitle(menu.curProfile); pt != "" {
 		account = pt
 	}
-	accounts := systray.AddMenuItem(account, "")
-	setRemoteIcon(accounts, menu.curProfile.UserProfile.ProfilePicURL)
-	time.Sleep(newMenuDelay)
-	for _, profile := range menu.allProfiles {
-		title := profileTitle(profile)
-		var item *systray.MenuItem
-		if profile.ID == menu.curProfile.ID {
-			item = accounts.AddSubMenuItemCheckbox(title, "", true)
-		} else {
-			item = accounts.AddSubMenuItem(title, "")
-		}
-		setRemoteIcon(item, profile.UserProfile.ProfilePicURL)
-		onClick(ctx, item, func(ctx context.Context) {
-			select {
-			case <-ctx.Done():
-			case menu.accountsCh <- profile.ID:
+	if !menu.readonly {
+		accounts := systray.AddMenuItem(account, "")
+		setRemoteIcon(accounts, menu.curProfile.UserProfile.ProfilePicURL)
+		time.Sleep(newMenuDelay)
+		for _, profile := range menu.allProfiles {
+			title := profileTitle(profile)
+			var item *systray.MenuItem
+			if profile.ID == menu.curProfile.ID {
+				item = accounts.AddSubMenuItemCheckbox(title, "", true)
+			} else {
+				item = accounts.AddSubMenuItem(title, "")
 			}
-		})
+			setRemoteIcon(item, profile.UserProfile.ProfilePicURL)
+			onClick(ctx, item, func(ctx context.Context) {
+				select {
+				case <-ctx.Done():
+				case menu.accountsCh <- profile.ID:
+				}
+			})
+		}
 	}
 
 	if menu.status != nil && menu.status.Self != nil && len(menu.status.Self.TailscaleIPs) > 0 {
@@ -255,7 +281,9 @@ func (menu *Menu) rebuild() {
 	}
 	systray.AddSeparator()
 
-	menu.rebuildExitNodeMenu(ctx)
+	if !menu.readonly {
+		menu.rebuildExitNodeMenu(ctx)
+	}
 
 	if menu.status != nil {
 		menu.more = systray.AddMenuItem("More settings", "")

client/tailscale/acl.go

@@ -12,6 +12,7 @@ import (
 	"fmt"
 	"net/http"
 	"net/netip"
+	"net/url"
 )
 
 // ACLRow defines a rule that grants access by a set of users or groups to a set
@@ -83,7 +84,7 @@ func (c *Client) ACL(ctx context.Context) (acl *ACL, err error) {
 		}
 	}()
 
-	path := fmt.Sprintf("%s/api/v2/tailnet/%s/acl", c.baseURL(), c.tailnet)
+	path := c.BuildTailnetURL("acl")
 	req, err := http.NewRequestWithContext(ctx, "GET", path, nil)
 	if err != nil {
 		return nil, err
@@ -97,7 +98,7 @@ func (c *Client) ACL(ctx context.Context) (acl *ACL, err error) {
 	// If status code was not successful, return the error.
 	// TODO: Change the check for the StatusCode to include other 2XX success codes.
 	if resp.StatusCode != http.StatusOK {
-		return nil, handleErrorResponse(b, resp)
+		return nil, HandleErrorResponse(b, resp)
 	}
 
 	// Otherwise, try to decode the response.
@@ -126,7 +127,7 @@ func (c *Client) ACLHuJSON(ctx context.Context) (acl *ACLHuJSON, err error) {
 		}
 	}()
 
-	path := fmt.Sprintf("%s/api/v2/tailnet/%s/acl?details=1", c.baseURL(), c.tailnet)
+	path := c.BuildTailnetURL("acl", url.Values{"details": {"1"}})
 	req, err := http.NewRequestWithContext(ctx, "GET", path, nil)
 	if err != nil {
 		return nil, err
@@ -138,7 +139,7 @@ func (c *Client) ACLHuJSON(ctx context.Context) (acl *ACLHuJSON, err error) {
 	}
 
 	if resp.StatusCode != http.StatusOK {
-		return nil, handleErrorResponse(b, resp)
+		return nil, HandleErrorResponse(b, resp)
 	}
 
 	data := struct {
@@ -146,7 +147,7 @@ func (c *Client) ACLHuJSON(ctx context.Context) (acl *ACLHuJSON, err error) {
 		Warnings []string `json:"warnings"`
 	}{}
 	if err := json.Unmarshal(b, &data); err != nil {
-		return nil, err
+		return nil, fmt.Errorf("json.Unmarshal %q: %w", b, err)
 	}
 
 	acl = &ACLHuJSON{
@@ -184,7 +185,7 @@ func (e ACLTestError) Error() string {
 }
 
 func (c *Client) aclPOSTRequest(ctx context.Context, body []byte, avoidCollisions bool, etag, acceptHeader string) ([]byte, string, error) {
-	path := fmt.Sprintf("%s/api/v2/tailnet/%s/acl", c.baseURL(), c.tailnet)
+	path := c.BuildTailnetURL("acl")
 	req, err := http.NewRequestWithContext(ctx, "POST", path, bytes.NewBuffer(body))
 	if err != nil {
 		return nil, "", err
@@ -328,7 +329,7 @@ type ACLPreview struct {
 }
 
 func (c *Client) previewACLPostRequest(ctx context.Context, body []byte, previewType string, previewFor string) (res *ACLPreviewResponse, err error) {
-	path := fmt.Sprintf("%s/api/v2/tailnet/%s/acl/preview", c.baseURL(), c.tailnet)
+	path := c.BuildTailnetURL("acl", "preview")
 	req, err := http.NewRequestWithContext(ctx, "POST", path, bytes.NewBuffer(body))
 	if err != nil {
 		return nil, err
@@ -350,7 +351,7 @@ func (c *Client) previewACLPostRequest(ctx context.Context, body []byte, preview
 	// If status code was not successful, return the error.
 	// TODO: Change the check for the StatusCode to include other 2XX success codes.
 	if resp.StatusCode != http.StatusOK {
-		return nil, handleErrorResponse(b, resp)
+		return nil, HandleErrorResponse(b, resp)
 	}
 	if err = json.Unmarshal(b, &res); err != nil {
 		return nil, err
@@ -488,7 +489,7 @@ func (c *Client) ValidateACLJSON(ctx context.Context, source, dest string) (test
 		return nil, err
 	}
 
-	path := fmt.Sprintf("%s/api/v2/tailnet/%s/acl/validate", c.baseURL(), c.tailnet)
+	path := c.BuildTailnetURL("acl", "validate")
 	req, err := http.NewRequestWithContext(ctx, "POST", path, bytes.NewBuffer(postData))
 	if err != nil {
 		return nil, err

client/tailscale/devices.go

@@ -131,7 +131,7 @@ func (c *Client) Devices(ctx context.Context, fields *DeviceFieldsOpts) (deviceL
 		}
 	}()
 
-	path := fmt.Sprintf("%s/api/v2/tailnet/%s/devices", c.baseURL(), c.tailnet)
+	path := c.BuildTailnetURL("devices")
 	req, err := http.NewRequestWithContext(ctx, "GET", path, nil)
 	if err != nil {
 		return nil, err
@@ -149,7 +149,7 @@ func (c *Client) Devices(ctx context.Context, fields *DeviceFieldsOpts) (deviceL
 	// If status code was not successful, return the error.
 	// TODO: Change the check for the StatusCode to include other 2XX success codes.
 	if resp.StatusCode != http.StatusOK {
-		return nil, handleErrorResponse(b, resp)
+		return nil, HandleErrorResponse(b, resp)
 	}
 
 	var devices GetDevicesResponse
@@ -188,7 +188,7 @@ func (c *Client) Device(ctx context.Context, deviceID string, fields *DeviceFiel
 	// If status code was not successful, return the error.
 	// TODO: Change the check for the StatusCode to include other 2XX success codes.
 	if resp.StatusCode != http.StatusOK {
-		return nil, handleErrorResponse(b, resp)
+		return nil, HandleErrorResponse(b, resp)
 	}
 
 	err = json.Unmarshal(b, &device)
@@ -221,7 +221,7 @@ func (c *Client) DeleteDevice(ctx context.Context, deviceID string) (err error)
 	// If status code was not successful, return the error.
 	// TODO: Change the check for the StatusCode to include other 2XX success codes.
 	if resp.StatusCode != http.StatusOK {
-		return handleErrorResponse(b, resp)
+		return HandleErrorResponse(b, resp)
 	}
 	return nil
 }
@@ -253,7 +253,7 @@ func (c *Client) SetAuthorized(ctx context.Context, deviceID string, authorized
 	// If status code was not successful, return the error.
 	// TODO: Change the check for the StatusCode to include other 2XX success codes.
 	if resp.StatusCode != http.StatusOK {
-		return handleErrorResponse(b, resp)
+		return HandleErrorResponse(b, resp)
 	}
 
 	return nil
@@ -281,7 +281,7 @@ func (c *Client) SetTags(ctx context.Context, deviceID string, tags []string) er
 	// If status code was not successful, return the error.
 	// TODO: Change the check for the StatusCode to include other 2XX success codes.
 	if resp.StatusCode != http.StatusOK {
-		return handleErrorResponse(b, resp)
+		return HandleErrorResponse(b, resp)
 	}
 
 	return nil

client/tailscale/dns.go

@@ -44,7 +44,7 @@ type DNSPreferences struct {
 }
 
 func (c *Client) dnsGETRequest(ctx context.Context, endpoint string) ([]byte, error) {
-	path := fmt.Sprintf("%s/api/v2/tailnet/%s/dns/%s", c.baseURL(), c.tailnet, endpoint)
+	path := c.BuildTailnetURL("dns", endpoint)
 	req, err := http.NewRequestWithContext(ctx, "GET", path, nil)
 	if err != nil {
 		return nil, err
@@ -57,14 +57,14 @@ func (c *Client) dnsGETRequest(ctx context.Context, endpoint string) ([]byte, er
 	// If status code was not successful, return the error.
 	// TODO: Change the check for the StatusCode to include other 2XX success codes.
 	if resp.StatusCode != http.StatusOK {
-		return nil, handleErrorResponse(b, resp)
+		return nil, HandleErrorResponse(b, resp)
 	}
 
 	return b, nil
 }
 
 func (c *Client) dnsPOSTRequest(ctx context.Context, endpoint string, postData any) ([]byte, error) {
-	path := fmt.Sprintf("%s/api/v2/tailnet/%s/dns/%s", c.baseURL(), c.tailnet, endpoint)
+	path := c.BuildTailnetURL("dns", endpoint)
 	data, err := json.Marshal(&postData)
 	if err != nil {
 		return nil, err
@@ -84,7 +84,7 @@ func (c *Client) dnsPOSTRequest(ctx context.Context, endpoint string, postData a
 	// If status code was not successful, return the error.
 	// TODO: Change the check for the StatusCode to include other 2XX success codes.
 	if resp.StatusCode != http.StatusOK {
-		return nil, handleErrorResponse(b, resp)
+		return nil, HandleErrorResponse(b, resp)
 	}
 
 	return b, nil

client/tailscale/keys.go

@@ -40,7 +40,7 @@ type KeyDeviceCreateCapabilities struct {
 
 // Keys returns the list of keys for the current user.
 func (c *Client) Keys(ctx context.Context) ([]string, error) {
-	path := fmt.Sprintf("%s/api/v2/tailnet/%s/keys", c.baseURL(), c.tailnet)
+	path := c.BuildTailnetURL("keys")
 	req, err := http.NewRequestWithContext(ctx, "GET", path, nil)
 	if err != nil {
 		return nil, err
@@ -51,7 +51,7 @@ func (c *Client) Keys(ctx context.Context) ([]string, error) {
 		return nil, err
 	}
 	if resp.StatusCode != http.StatusOK {
-		return nil, handleErrorResponse(b, resp)
+		return nil, HandleErrorResponse(b, resp)
 	}
 
 	var keys struct {
@@ -99,7 +99,7 @@ func (c *Client) CreateKeyWithExpiry(ctx context.Context, caps KeyCapabilities,
 		return "", nil, err
 	}
 
-	path := fmt.Sprintf("%s/api/v2/tailnet/%s/keys", c.baseURL(), c.tailnet)
+	path := c.BuildTailnetURL("keys")
 	req, err := http.NewRequestWithContext(ctx, "POST", path, bytes.NewReader(bs))
 	if err != nil {
 		return "", nil, err
@@ -110,7 +110,7 @@ func (c *Client) CreateKeyWithExpiry(ctx context.Context, caps KeyCapabilities,
 		return "", nil, err
 	}
 	if resp.StatusCode != http.StatusOK {
-		return "", nil, handleErrorResponse(b, resp)
+		return "", nil, HandleErrorResponse(b, resp)
 	}
 
 	var key struct {
@@ -126,7 +126,7 @@ func (c *Client) CreateKeyWithExpiry(ctx context.Context, caps KeyCapabilities,
 // Key returns the metadata for the given key ID. Currently, capabilities are
 // only returned for auth keys, API keys only return general metadata.
 func (c *Client) Key(ctx context.Context, id string) (*Key, error) {
-	path := fmt.Sprintf("%s/api/v2/tailnet/%s/keys/%s", c.baseURL(), c.tailnet, id)
+	path := c.BuildTailnetURL("keys", id)
 	req, err := http.NewRequestWithContext(ctx, "GET", path, nil)
 	if err != nil {
 		return nil, err
@@ -137,7 +137,7 @@ func (c *Client) Key(ctx context.Context, id string) (*Key, error) {
 		return nil, err
 	}
 	if resp.StatusCode != http.StatusOK {
-		return nil, handleErrorResponse(b, resp)
+		return nil, HandleErrorResponse(b, resp)
 	}
 
 	var key Key
@@ -149,7 +149,7 @@ func (c *Client) Key(ctx context.Context, id string) (*Key, error) {
 
 // DeleteKey deletes the key with the given ID.
 func (c *Client) DeleteKey(ctx context.Context, id string) error {
-	path := fmt.Sprintf("%s/api/v2/tailnet/%s/keys/%s", c.baseURL(), c.tailnet, id)
+	path := c.BuildTailnetURL("keys", id)
 	req, err := http.NewRequestWithContext(ctx, "DELETE", path, nil)
 	if err != nil {
 		return err
@@ -160,7 +160,7 @@ func (c *Client) DeleteKey(ctx context.Context, id string) error {
 		return err
 	}
 	if resp.StatusCode != http.StatusOK {
-		return handleErrorResponse(b, resp)
+		return HandleErrorResponse(b, resp)
 	}
 	return nil
 }

client/tailscale/routes.go

@@ -44,7 +44,7 @@ func (c *Client) Routes(ctx context.Context, deviceID string) (routes *Routes, e
 	// If status code was not successful, return the error.
 	// TODO: Change the check for the StatusCode to include other 2XX success codes.
 	if resp.StatusCode != http.StatusOK {
-		return nil, handleErrorResponse(b, resp)
+		return nil, HandleErrorResponse(b, resp)
 	}
 
 	var sr Routes
@@ -84,7 +84,7 @@ func (c *Client) SetRoutes(ctx context.Context, deviceID string, subnets []netip
 	// If status code was not successful, return the error.
 	// TODO: Change the check for the StatusCode to include other 2XX success codes.
 	if resp.StatusCode != http.StatusOK {
-		return nil, handleErrorResponse(b, resp)
+		return nil, HandleErrorResponse(b, resp)
 	}
 
 	var srr *Routes

client/tailscale/tailnet.go

@@ -9,7 +9,6 @@ import (
 	"context"
 	"fmt"
 	"net/http"
-	"net/url"
 
 	"tailscale.com/util/httpm"
 )
@@ -22,7 +21,7 @@ func (c *Client) TailnetDeleteRequest(ctx context.Context, tailnetID string) (er
 		}
 	}()
 
-	path := fmt.Sprintf("%s/api/v2/tailnet/%s", c.baseURL(), url.PathEscape(string(tailnetID)))
+	path := c.BuildTailnetURL("tailnet")
 	req, err := http.NewRequestWithContext(ctx, httpm.DELETE, path, nil)
 	if err != nil {
 		return err
@@ -35,7 +34,7 @@ func (c *Client) TailnetDeleteRequest(ctx context.Context, tailnetID string) (er
 	}
 
 	if resp.StatusCode != http.StatusOK {
-		return handleErrorResponse(b, resp)
+		return HandleErrorResponse(b, resp)
 	}
 
 	return nil

client/tailscale/tailscale.go

@@ -5,8 +5,10 @@
 
 // Package tailscale contains a Go client for the Tailscale control plane API.
 //
-// Warning: this package is in development and makes no API compatibility
-// promises as of 2022-04-29. It is subject to change at any time.
+// This package is only intended for internal and transitional use.
+//
+// Deprecated: the official control plane client is available at
+// tailscale.com/client/tailscale/v2.
 package tailscale
 
 import (
@@ -15,13 +17,12 @@ import (
 	"fmt"
 	"io"
 	"net/http"
+	"net/url"
+	"path"
 )
 
 // I_Acknowledge_This_API_Is_Unstable must be set true to use this package
-// for now. It was added 2022-04-29 when it was moved to this git repo
-// and will be removed when the public API has settled.
-//
-// TODO(bradfitz): remove this after the we're happy with the public API.
+// for now. This package is being replaced by tailscale.com/client/tailscale/v2.
 var I_Acknowledge_This_API_Is_Unstable = false
 
 // TODO: use url.PathEscape() for deviceID and tailnets when constructing requests.
@@ -35,6 +36,8 @@ const maxReadSize = 10 << 20
 //
 // Use NewClient to instantiate one. Exported fields should be set before
 // the client is used and not changed thereafter.
+//
+// Deprecated: use tailscale.com/client/tailscale/v2 instead.
 type Client struct {
 	// tailnet is the globally unique identifier for a Tailscale network, such
 	// as "example.com" or "user@gmail.com".
@@ -62,6 +65,46 @@ func (c *Client) httpClient() *http.Client {
 	return http.DefaultClient
 }
 
+// BuildURL builds a url to http(s)://<apiserver>/api/v2/<slash-separated-pathElements>
+// using the given pathElements. It url escapes each path element, so the
+// caller doesn't need to worry about that. The last item of pathElements can
+// be of type url.Values to add a query string to the URL.
+//
+// For example, BuildURL(devices, 5) with the default server URL would result in
+// https://api.tailscale.com/api/v2/devices/5.
+func (c *Client) BuildURL(pathElements ...any) string {
+	elem := make([]string, 1, len(pathElements)+1)
+	elem[0] = "/api/v2"
+	var query string
+	for i, pathElement := range pathElements {
+		if uv, ok := pathElement.(url.Values); ok && i == len(pathElements)-1 {
+			query = uv.Encode()
+		} else {
+			elem = append(elem, url.PathEscape(fmt.Sprint(pathElement)))
+		}
+	}
+	url := c.baseURL() + path.Join(elem...)
+	if query != "" {
+		url += "?" + query
+	}
+	return url
+}
+
+// BuildTailnetURL builds a url to http(s)://<apiserver>/api/v2/tailnet/<tailnet>/<slash-separated-pathElements>
+// using the given pathElements. It url escapes each path element, so the
+// caller doesn't need to worry about that. The last item of pathElements can
+// be of type url.Values to add a query string to the URL.
+//
+// For example, BuildTailnetURL(policy, validate) with the default server URL and a tailnet of "example.com"
+// would result in https://api.tailscale.com/api/v2/tailnet/example.com/policy/validate.
+func (c *Client) BuildTailnetURL(pathElements ...any) string {
+	allElements := make([]any, 2, len(pathElements)+2)
+	allElements[0] = "tailnet"
+	allElements[1] = c.tailnet
+	allElements = append(allElements, pathElements...)
+	return c.BuildURL(allElements...)
+}
+
 func (c *Client) baseURL() string {
 	if c.BaseURL != "" {
 		return c.BaseURL
@@ -97,6 +140,8 @@ func (c *Client) setAuth(r *http.Request) {
 // If httpClient is nil, then http.DefaultClient is used.
 // "api.tailscale.com" is set as the BaseURL for the returned client
 // and can be changed manually by the user.
+//
+// Deprecated: use tailscale.com/client/tailscale/v2 instead.
 func NewClient(tailnet string, auth AuthMethod) *Client {
 	return &Client{
 		tailnet:   tailnet,
@@ -147,12 +192,14 @@ func (e ErrResponse) Error() string {
 	return fmt.Sprintf("Status: %d, Message: %q", e.Status, e.Message)
 }
 
-// handleErrorResponse decodes the error message from the server and returns
+// HandleErrorResponse decodes the error message from the server and returns
 // an ErrResponse from it.
-func handleErrorResponse(b []byte, resp *http.Response) error {
+//
+// Deprecated: use tailscale.com/client/tailscale/v2 instead.
+func HandleErrorResponse(b []byte, resp *http.Response) error {
 	var errResp ErrResponse
 	if err := json.Unmarshal(b, &errResp); err != nil {
-		return err
+		return fmt.Errorf("json.Unmarshal %q: %w", b, err)
 	}
 	errResp.Status = resp.StatusCode
 	return errResp

client/tailscale/tailscale_test.go

@@ -0,0 +1,86 @@
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
+
+package tailscale
+
+import (
+	"net/url"
+	"testing"
+)
+
+func TestClientBuildURL(t *testing.T) {
+	c := Client{BaseURL: "http://127.0.0.1:1234"}
+	for _, tt := range []struct {
+		desc     string
+		elements []any
+		want     string
+	}{
+		{
+			desc:     "single-element",
+			elements: []any{"devices"},
+			want:     "http://127.0.0.1:1234/api/v2/devices",
+		},
+		{
+			desc:     "multiple-elements",
+			elements: []any{"tailnet", "example.com"},
+			want:     "http://127.0.0.1:1234/api/v2/tailnet/example.com",
+		},
+		{
+			desc:     "escape-element",
+			elements: []any{"tailnet", "example dot com?foo=bar"},
+			want:     `http://127.0.0.1:1234/api/v2/tailnet/example%20dot%20com%3Ffoo=bar`,
+		},
+		{
+			desc:     "url.Values",
+			elements: []any{"tailnet", "example.com", "acl", url.Values{"details": {"1"}}},
+			want:     `http://127.0.0.1:1234/api/v2/tailnet/example.com/acl?details=1`,
+		},
+	} {
+		t.Run(tt.desc, func(t *testing.T) {
+			got := c.BuildURL(tt.elements...)
+			if got != tt.want {
+				t.Errorf("got %q, want %q", got, tt.want)
+			}
+		})
+	}
+}
+
+func TestClientBuildTailnetURL(t *testing.T) {
+	c := Client{
+		BaseURL: "http://127.0.0.1:1234",
+		tailnet: "example.com",
+	}
+	for _, tt := range []struct {
+		desc     string
+		elements []any
+		want     string
+	}{
+		{
+			desc:     "single-element",
+			elements: []any{"devices"},
+			want:     "http://127.0.0.1:1234/api/v2/tailnet/example.com/devices",
+		},
+		{
+			desc:     "multiple-elements",
+			elements: []any{"devices", 123},
+			want:     "http://127.0.0.1:1234/api/v2/tailnet/example.com/devices/123",
+		},
+		{
+			desc:     "escape-element",
+			elements: []any{"foo bar?baz=qux"},
+			want:     `http://127.0.0.1:1234/api/v2/tailnet/example.com/foo%20bar%3Fbaz=qux`,
+		},
+		{
+			desc:     "url.Values",
+			elements: []any{"acl", url.Values{"details": {"1"}}},
+			want:     `http://127.0.0.1:1234/api/v2/tailnet/example.com/acl?details=1`,
+		},
+	} {
+		t.Run(tt.desc, func(t *testing.T) {
+			got := c.BuildTailnetURL(tt.elements...)
+			if got != tt.want {
+				t.Errorf("got %q, want %q", got, tt.want)
+			}
+		})
+	}
+}

client/web/web.go

@@ -203,35 +203,9 @@ func NewServer(opts ServerOpts) (s *Server, err error) {
 	}
 	s.assetsHandler, s.assetsCleanup = assetsHandler(s.devMode)
 
-	var metric string // clientmetric to report on startup
-
-	// Create handler for "/api" requests with CSRF protection.
-	// We don't require secure cookies, since the web client is regularly used
-	// on network appliances that are served on local non-https URLs.
-	// The client is secured by limiting the interface it listens on,
-	// or by authenticating requests before they reach the web client.
-	csrfProtect := csrf.Protect(s.csrfKey(), csrf.Secure(false))
-
-	// signal to the CSRF middleware that the request is being served over
-	// plaintext HTTP to skip TLS-only header checks.
-	withSetPlaintext := func(h http.Handler) http.Handler {
-		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-			r = csrf.PlaintextHTTPRequest(r)
-			h.ServeHTTP(w, r)
-		})
-	}
-
-	switch s.mode {
-	case LoginServerMode:
-		s.apiHandler = csrfProtect(withSetPlaintext(http.HandlerFunc(s.serveLoginAPI)))
-		metric = "web_login_client_initialization"
-	case ReadOnlyServerMode:
-		s.apiHandler = csrfProtect(withSetPlaintext(http.HandlerFunc(s.serveLoginAPI)))
-		metric = "web_readonly_client_initialization"
-	case ManageServerMode:
-		s.apiHandler = csrfProtect(withSetPlaintext(http.HandlerFunc(s.serveAPI)))
-		metric = "web_client_initialization"
-	}
+	var metric string
+	s.apiHandler, metric = s.modeAPIHandler(s.mode)
+	s.apiHandler = s.withCSRF(s.apiHandler)
 
 	// Don't block startup on reporting metric.
 	// Report in separate go routine with 5 second timeout.
@@ -244,6 +218,39 @@ func NewServer(opts ServerOpts) (s *Server, err error) {
 	return s, nil
 }
 
+func (s *Server) withCSRF(h http.Handler) http.Handler {
+	csrfProtect := csrf.Protect(s.csrfKey(), csrf.Secure(false))
+
+	// ref https://github.com/tailscale/tailscale/pull/14822
+	// signal to the CSRF middleware that the request is being served over
+	// plaintext HTTP to skip TLS-only header checks.
+	withSetPlaintext := func(h http.Handler) http.Handler {
+		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			r = csrf.PlaintextHTTPRequest(r)
+			h.ServeHTTP(w, r)
+		})
+	}
+
+	// NB: the order of the withSetPlaintext and csrfProtect calls is important
+	// to ensure that we signal to the CSRF middleware that the request is being
+	// served over plaintext HTTP and not over TLS as it presumes by default.
+	return withSetPlaintext(csrfProtect(h))
+}
+
+func (s *Server) modeAPIHandler(mode ServerMode) (http.Handler, string) {
+	switch mode {
+	case LoginServerMode:
+		return http.HandlerFunc(s.serveLoginAPI), "web_login_client_initialization"
+	case ReadOnlyServerMode:
+		return http.HandlerFunc(s.serveLoginAPI), "web_readonly_client_initialization"
+	case ManageServerMode:
+		return http.HandlerFunc(s.serveAPI), "web_client_initialization"
+	default: // invalid mode
+		log.Fatalf("invalid mode: %v", mode)
+	}
+	return nil, ""
+}
+
 func (s *Server) Shutdown() {
 	s.logf("web.Server: shutting down")
 	if s.assetsCleanup != nil {

client/web/web_test.go

@@ -11,6 +11,7 @@ import (
 	"fmt"
 	"io"
 	"net/http"
+	"net/http/cookiejar"
 	"net/http/httptest"
 	"net/netip"
 	"net/url"
@@ -20,6 +21,7 @@ import (
 	"time"
 
 	"github.com/google/go-cmp/cmp"
+	"github.com/gorilla/csrf"
 	"tailscale.com/client/local"
 	"tailscale.com/client/tailscale/apitype"
 	"tailscale.com/ipn"
@@ -1477,3 +1479,83 @@ func mockWaitAuthURL(_ context.Context, id string, src tailcfg.NodeID) (*tailcfg
 		return nil, errors.New("unknown id")
 	}
 }
+
+func TestCSRFProtect(t *testing.T) {
+	s := &Server{}
+
+	mux := http.NewServeMux()
+	mux.HandleFunc("GET /test/csrf-token", func(w http.ResponseWriter, r *http.Request) {
+		token := csrf.Token(r)
+		_, err := io.WriteString(w, token)
+		if err != nil {
+			t.Fatal(err)
+		}
+	})
+	mux.HandleFunc("POST /test/csrf-protected", func(w http.ResponseWriter, r *http.Request) {
+		_, err := io.WriteString(w, "ok")
+		if err != nil {
+			t.Fatal(err)
+		}
+	})
+	h := s.withCSRF(mux)
+	ser := httptest.NewServer(h)
+	defer ser.Close()
+
+	jar, err := cookiejar.New(nil)
+	if err != nil {
+		t.Fatalf("unable to construct cookie jar: %v", err)
+	}
+
+	client := ser.Client()
+	client.Jar = jar
+
+	// make GET request to populate cookie jar
+	resp, err := client.Get(ser.URL + "/test/csrf-token")
+	if err != nil {
+		t.Fatalf("unable to make request: %v", err)
+	}
+	defer resp.Body.Close()
+	if resp.StatusCode != http.StatusOK {
+		t.Fatalf("unexpected status: %v", resp.Status)
+	}
+	tokenBytes, err := io.ReadAll(resp.Body)
+	if err != nil {
+		t.Fatalf("unable to read body: %v", err)
+	}
+
+	csrfToken := strings.TrimSpace(string(tokenBytes))
+	if csrfToken == "" {
+		t.Fatal("empty csrf token")
+	}
+
+	// make a POST request without the CSRF header; ensure it fails
+	resp, err = client.Post(ser.URL+"/test/csrf-protected", "text/plain", nil)
+	if err != nil {
+		t.Fatalf("unable to make request: %v", err)
+	}
+	if resp.StatusCode != http.StatusForbidden {
+		t.Fatalf("unexpected status: %v", resp.Status)
+	}
+
+	// make a POST request with the CSRF header; ensure it succeeds
+	req, err := http.NewRequest("POST", ser.URL+"/test/csrf-protected", nil)
+	if err != nil {
+		t.Fatalf("error building request: %v", err)
+	}
+	req.Header.Set("X-CSRF-Token", csrfToken)
+	resp, err = client.Do(req)
+	if err != nil {
+		t.Fatalf("unable to make request: %v", err)
+	}
+	if resp.StatusCode != http.StatusOK {
+		t.Fatalf("unexpected status: %v", resp.Status)
+	}
+	defer resp.Body.Close()
+	out, err := io.ReadAll(resp.Body)
+	if err != nil {
+		t.Fatalf("unable to read body: %v", err)
+	}
+	if string(out) != "ok" {
+		t.Fatalf("unexpected body: %q", out)
+	}
+}

cmd/derper/depaware.txt

@@ -191,13 +191,11 @@ tailscale.com/cmd/derper dependencies: (generated by github.com/tailscale/depawa
         golang.org/x/crypto/cryptobyte                               from crypto/ecdsa+
         golang.org/x/crypto/cryptobyte/asn1                          from crypto/ecdsa+
         golang.org/x/crypto/curve25519                               from golang.org/x/crypto/nacl/box+
-        golang.org/x/crypto/hkdf                                     from crypto/tls+
         golang.org/x/crypto/internal/alias                           from golang.org/x/crypto/chacha20+
         golang.org/x/crypto/internal/poly1305                        from golang.org/x/crypto/chacha20poly1305+
         golang.org/x/crypto/nacl/box                                 from tailscale.com/types/key
         golang.org/x/crypto/nacl/secretbox                           from golang.org/x/crypto/nacl/box
         golang.org/x/crypto/salsa20/salsa                            from golang.org/x/crypto/nacl/box+
-        golang.org/x/crypto/sha3                                     from crypto/internal/mlkem768+
    W    golang.org/x/exp/constraints                                 from tailscale.com/util/winutil
         golang.org/x/exp/maps                                        from tailscale.com/util/syspolicy/setting+
    L    golang.org/x/net/bpf                                         from github.com/mdlayher/netlink+
@@ -230,7 +228,7 @@ tailscale.com/cmd/derper dependencies: (generated by github.com/tailscale/depawa
         container/list                                               from crypto/tls+
         context                                                      from crypto/tls+
         crypto                                                       from crypto/ecdh+
-        crypto/aes                                                   from crypto/ecdsa+
+        crypto/aes                                                   from crypto/internal/hpke+
         crypto/cipher                                                from crypto/aes+
         crypto/des                                                   from crypto/tls+
         crypto/dsa                                                   from crypto/x509
@@ -239,31 +237,58 @@ tailscale.com/cmd/derper dependencies: (generated by github.com/tailscale/depawa
         crypto/ed25519                                               from crypto/tls+
         crypto/elliptic                                              from crypto/ecdsa+
         crypto/hmac                                                  from crypto/tls+
-        crypto/internal/alias                                        from crypto/aes+
-        crypto/internal/bigmod                                       from crypto/ecdsa+
         crypto/internal/boring                                       from crypto/aes+
         crypto/internal/boring/bbig                                  from crypto/ecdsa+
         crypto/internal/boring/sig                                   from crypto/internal/boring
-        crypto/internal/edwards25519                                 from crypto/ed25519
-        crypto/internal/edwards25519/field                           from crypto/ecdh+
+        crypto/internal/entropy                                      from crypto/internal/fips140/drbg
+        crypto/internal/fips140                                      from crypto/internal/fips140/aes+
+        crypto/internal/fips140/aes                                  from crypto/aes+
+        crypto/internal/fips140/aes/gcm                              from crypto/cipher+
+        crypto/internal/fips140/alias                                from crypto/cipher+
+        crypto/internal/fips140/bigmod                               from crypto/internal/fips140/ecdsa+
+        crypto/internal/fips140/check                                from crypto/internal/fips140/aes+
+        crypto/internal/fips140/drbg                                 from crypto/internal/fips140/aes/gcm+
+        crypto/internal/fips140/ecdh                                 from crypto/ecdh
+        crypto/internal/fips140/ecdsa                                from crypto/ecdsa
+        crypto/internal/fips140/ed25519                              from crypto/ed25519
+        crypto/internal/fips140/edwards25519                         from crypto/internal/fips140/ed25519
+        crypto/internal/fips140/edwards25519/field                   from crypto/ecdh+
+        crypto/internal/fips140/hkdf                                 from crypto/internal/fips140/tls13+
+        crypto/internal/fips140/hmac                                 from crypto/hmac+
+        crypto/internal/fips140/mlkem                                from crypto/tls
+        crypto/internal/fips140/nistec                               from crypto/elliptic+
+        crypto/internal/fips140/nistec/fiat                          from crypto/internal/fips140/nistec
+        crypto/internal/fips140/rsa                                  from crypto/rsa
+        crypto/internal/fips140/sha256                               from crypto/internal/fips140/check+
+        crypto/internal/fips140/sha3                                 from crypto/internal/fips140/hmac+
+        crypto/internal/fips140/sha512                               from crypto/internal/fips140/ecdsa+
+        crypto/internal/fips140/subtle                               from crypto/internal/fips140/aes+
+        crypto/internal/fips140/tls12                                from crypto/tls
+        crypto/internal/fips140/tls13                                from crypto/tls
+        crypto/internal/fips140deps/byteorder                        from crypto/internal/fips140/aes+
+        crypto/internal/fips140deps/cpu                              from crypto/internal/fips140/aes+
+        crypto/internal/fips140deps/godebug                          from crypto/internal/fips140+
+        crypto/internal/fips140hash                                  from crypto/ecdsa+
+        crypto/internal/fips140only                                  from crypto/cipher+
         crypto/internal/hpke                                         from crypto/tls
-        crypto/internal/mlkem768                                     from crypto/tls
-        crypto/internal/nistec                                       from crypto/ecdh+
-        crypto/internal/nistec/fiat                                  from crypto/internal/nistec
+        crypto/internal/impl                                         from crypto/internal/fips140/aes+
         crypto/internal/randutil                                     from crypto/dsa+
+        crypto/internal/sysrand                                      from crypto/internal/entropy+
         crypto/md5                                                   from crypto/tls+
         crypto/rand                                                  from crypto/ed25519+
         crypto/rc4                                                   from crypto/tls
         crypto/rsa                                                   from crypto/tls+
         crypto/sha1                                                  from crypto/tls+
         crypto/sha256                                                from crypto/tls+
+        crypto/sha3                                                  from crypto/internal/fips140hash
         crypto/sha512                                                from crypto/ecdsa+
-        crypto/subtle                                                from crypto/aes+
+        crypto/subtle                                                from crypto/cipher+
         crypto/tls                                                   from golang.org/x/crypto/acme+
+        crypto/tls/internal/fips140tls                               from crypto/tls
         crypto/x509                                                  from crypto/tls+
    D    crypto/x509/internal/macos                                   from crypto/x509
         crypto/x509/pkix                                             from crypto/x509+
-        embed                                                        from crypto/internal/nistec+
+        embed                                                        from google.golang.org/protobuf/internal/editiondefaults+
         encoding                                                     from encoding/json+
         encoding/asn1                                                from crypto/x509+
         encoding/base32                                              from github.com/fxamacker/cbor/v2+
@@ -284,23 +309,22 @@ tailscale.com/cmd/derper dependencies: (generated by github.com/tailscale/depawa
         html                                                         from net/http/pprof+
         html/template                                                from tailscale.com/cmd/derper
         internal/abi                                                 from crypto/x509/internal/macos+
-        internal/asan                                                from syscall
+        internal/asan                                                from syscall+
         internal/bisect                                              from internal/godebug
         internal/bytealg                                             from bytes+
-        internal/byteorder                                           from crypto/aes+
+        internal/byteorder                                           from crypto/cipher+
         internal/chacha8rand                                         from math/rand/v2+
-        internal/concurrent                                          from unique
         internal/coverage/rtcov                                      from runtime
-        internal/cpu                                                 from crypto/aes+
+        internal/cpu                                                 from crypto/internal/fips140deps/cpu+
         internal/filepathlite                                        from os+
         internal/fmtsort                                             from fmt+
-        internal/goarch                                              from crypto/aes+
+        internal/goarch                                              from crypto/internal/fips140deps/cpu+
         internal/godebug                                             from crypto/tls+
         internal/godebugs                                            from internal/godebug+
-        internal/goexperiment                                        from runtime
+        internal/goexperiment                                        from runtime+
         internal/goos                                                from crypto/x509+
         internal/itoa                                                from internal/poll+
-        internal/msan                                                from syscall
+        internal/msan                                                from syscall+
         internal/nettrace                                            from net+
         internal/oserror                                             from io/fs+
         internal/poll                                                from net+
@@ -310,17 +334,20 @@ tailscale.com/cmd/derper dependencies: (generated by github.com/tailscale/depawa
         internal/reflectlite                                         from context+
         internal/runtime/atomic                                      from internal/runtime/exithook+
         internal/runtime/exithook                                    from runtime
+        internal/runtime/maps                                        from reflect+
+        internal/runtime/math                                        from internal/runtime/maps+
+        internal/runtime/sys                                         from crypto/subtle+
    L    internal/runtime/syscall                                     from runtime+
         internal/singleflight                                        from net
         internal/stringslite                                         from embed+
+        internal/sync                                                from sync+
         internal/syscall/execenv                                     from os+
-  LD    internal/syscall/unix                                        from crypto/rand+
-   W    internal/syscall/windows                                     from crypto/rand+
+  LD    internal/syscall/unix                                        from crypto/internal/sysrand+
+   W    internal/syscall/windows                                     from crypto/internal/sysrand+
    W    internal/syscall/windows/registry                            from mime+
    W    internal/syscall/windows/sysdll                              from internal/syscall/windows+
         internal/testlog                                             from os
         internal/unsafeheader                                        from internal/reflectlite+
-        internal/weak                                                from unique
         io                                                           from bufio+
         io/fs                                                        from crypto/x509+
    L    io/ioutil                                                    from github.com/mitchellh/go-ps+
@@ -332,7 +359,7 @@ tailscale.com/cmd/derper dependencies: (generated by github.com/tailscale/depawa
         math/big                                                     from crypto/dsa+
         math/bits                                                    from compress/flate+
         math/rand                                                    from github.com/mdlayher/netlink+
-        math/rand/v2                                                 from internal/concurrent+
+        math/rand/v2                                                 from crypto/ecdsa+
         mime                                                         from github.com/prometheus/common/expfmt+
         mime/multipart                                               from net/http
         mime/quotedprintable                                         from mime/multipart
@@ -345,7 +372,7 @@ tailscale.com/cmd/derper dependencies: (generated by github.com/tailscale/depawa
         net/netip                                                    from go4.org/netipx+
         net/textproto                                                from golang.org/x/net/http/httpguts+
         net/url                                                      from crypto/x509+
-        os                                                           from crypto/rand+
+        os                                                           from crypto/internal/sysrand+
         os/exec                                                      from github.com/coreos/go-iptables/iptables+
         os/signal                                                    from tailscale.com/cmd/derper
    W    os/user                                                      from tailscale.com/util/winutil+
@@ -354,10 +381,8 @@ tailscale.com/cmd/derper dependencies: (generated by github.com/tailscale/depawa
         reflect                                                      from crypto/x509+
         regexp                                                       from github.com/coreos/go-iptables/iptables+
         regexp/syntax                                                from regexp
-        runtime                                                      from crypto/internal/nistec+
+        runtime                                                      from crypto/internal/fips140+
         runtime/debug                                                from github.com/prometheus/client_golang/prometheus+
-        runtime/internal/math                                        from runtime
-        runtime/internal/sys                                         from runtime
         runtime/metrics                                              from github.com/prometheus/client_golang/prometheus+
         runtime/pprof                                                from net/http/pprof
         runtime/trace                                                from net/http/pprof
@@ -367,7 +392,7 @@ tailscale.com/cmd/derper dependencies: (generated by github.com/tailscale/depawa
         strings                                                      from bufio+
         sync                                                         from compress/flate+
         sync/atomic                                                  from context+
-        syscall                                                      from crypto/rand+
+        syscall                                                      from crypto/internal/sysrand+
         text/tabwriter                                               from runtime/pprof
         text/template                                                from html/template
         text/template/parse                                          from html/template+
@@ -377,3 +402,4 @@ tailscale.com/cmd/derper dependencies: (generated by github.com/tailscale/depawa
         unicode/utf8                                                 from bufio+
         unique                                                       from net/netip
         unsafe                                                       from bytes+
+        weak                                                         from unique

cmd/derper/derper.go

@@ -71,10 +71,13 @@ var (
 	secretsCacheDir = flag.String("secrets-cache-dir", defaultSetecCacheDir(), "directory to cache setec secrets in (required if --secrets-url is set)")
 	bootstrapDNS    = flag.String("bootstrap-dns-names", "", "optional comma-separated list of hostnames to make available at /bootstrap-dns")
 	unpublishedDNS  = flag.String("unpublished-bootstrap-dns-names", "", "optional comma-separated list of hostnames to make available at /bootstrap-dns and not publish in the list. If an entry contains a slash, the second part names a DNS record to poll for its TXT record with a `0` to `100` value for rollout percentage.")
+
 	verifyClients   = flag.Bool("verify-clients", false, "verify clients to this DERP server through a local tailscaled instance.")
 	verifyClientURL = flag.String("verify-client-url", "", "if non-empty, an admission controller URL for permitting client connections; see tailcfg.DERPAdmitClientRequest")
 	verifyFailOpen  = flag.Bool("verify-client-url-fail-open", true, "whether we fail open if --verify-client-url is unreachable")
 
+	socket = flag.String("socket", "", "optional alternate path to tailscaled socket (only relevant when using --verify-clients)")
+
 	acceptConnLimit = flag.Float64("accept-connection-limit", math.Inf(+1), "rate limit for accepting new connection")
 	acceptConnBurst = flag.Int("accept-connection-burst", math.MaxInt, "burst limit for accepting new connection")
 
@@ -192,6 +195,7 @@ func main() {
 
 	s := derp.NewServer(cfg.PrivateKey, log.Printf)
 	s.SetVerifyClient(*verifyClients)
+	s.SetTailscaledSocketPath(*socket)
 	s.SetVerifyClientURL(*verifyClientURL)
 	s.SetVerifyClientURLFailOpen(*verifyFailOpen)
 	s.SetTCPWriteTimeout(*tcpWriteTimeout)
@@ -324,6 +328,9 @@ func main() {
 		Control:   ktimeout.UserTimeout(*tcpUserTimeout),
 		KeepAlive: *tcpKeepAlive,
 	}
+	// As of 2025-02-19, MPTCP does not support TCP_USER_TIMEOUT socket option
+	// set in ktimeout.UserTimeout above.
+	lc.SetMultipathTCP(false)
 
 	quietLogger := log.New(logger.HTTPServerLogFilter{Inner: log.Printf}, "", 0)
 	httpsrv := &http.Server{

cmd/get-authkey/main.go

@@ -16,14 +16,10 @@ import (
 	"strings"
 
 	"golang.org/x/oauth2/clientcredentials"
-	"tailscale.com/client/tailscale"
+	"tailscale.com/internal/client/tailscale"
 )
 
 func main() {
-	// Required to use our client API. We're fine with the instability since the
-	// client lives in the same repo as this code.
-	tailscale.I_Acknowledge_This_API_Is_Unstable = true
-
 	reusable := flag.Bool("reusable", false, "allocate a reusable authkey")
 	ephemeral := flag.Bool("ephemeral", false, "allocate an ephemeral authkey")
 	preauth := flag.Bool("preauth", true, "set the authkey as pre-authorized")

cmd/gitops-pusher/gitops-pusher.go

@@ -13,6 +13,7 @@ import (
 	"encoding/json"
 	"flag"
 	"fmt"
+	"io"
 	"log"
 	"net/http"
 	"os"
@@ -405,7 +406,8 @@ func getACLETag(ctx context.Context, client *http.Client, tailnet, apiKey string
 	got := resp.StatusCode
 	want := http.StatusOK
 	if got != want {
-		return "", fmt.Errorf("wanted HTTP status code %d but got %d", want, got)
+		errorDetails, _ := io.ReadAll(resp.Body)
+		return "", fmt.Errorf("wanted HTTP status code %d but got %d: %#q", want, got, string(errorDetails))
 	}
 
 	return Shuck(resp.Header.Get("ETag")), nil

cmd/k8s-operator/depaware.txt

@@ -81,7 +81,6 @@ tailscale.com/cmd/k8s-operator dependencies: (generated by github.com/tailscale/
    L    github.com/aws/smithy-go/transport/http/internal/io          from github.com/aws/smithy-go/transport/http
    L    github.com/aws/smithy-go/waiter                              from github.com/aws/aws-sdk-go-v2/service/ssm
         github.com/beorn7/perks/quantile                             from github.com/prometheus/client_golang/prometheus
-        github.com/bits-and-blooms/bitset                            from github.com/gaissmai/bart
      💣 github.com/cespare/xxhash/v2                                 from github.com/prometheus/client_golang/prometheus
    L    github.com/coreos/go-iptables/iptables                       from tailscale.com/util/linuxfw
      💣 github.com/davecgh/go-spew/spew                              from k8s.io/apimachinery/pkg/util/dump
@@ -99,6 +98,8 @@ tailscale.com/cmd/k8s-operator dependencies: (generated by github.com/tailscale/
      💣 github.com/fsnotify/fsnotify                                 from sigs.k8s.io/controller-runtime/pkg/certwatcher
         github.com/fxamacker/cbor/v2                                 from tailscale.com/tka+
         github.com/gaissmai/bart                                     from tailscale.com/net/ipset+
+        github.com/gaissmai/bart/internal/bitset                     from github.com/gaissmai/bart+
+        github.com/gaissmai/bart/internal/sparse                     from github.com/gaissmai/bart
         github.com/go-json-experiment/json                           from tailscale.com/types/opt+
         github.com/go-json-experiment/json/internal                  from github.com/go-json-experiment/json/internal/jsonflags+
         github.com/go-json-experiment/json/internal/jsonflags        from github.com/go-json-experiment/json/internal/jsonopts+
@@ -810,9 +811,11 @@ tailscale.com/cmd/k8s-operator dependencies: (generated by github.com/tailscale/
         tailscale.com/health                                         from tailscale.com/control/controlclient+
         tailscale.com/health/healthmsg                               from tailscale.com/ipn/ipnlocal
         tailscale.com/hostinfo                                       from tailscale.com/client/web+
+        tailscale.com/internal/client/tailscale                      from tailscale.com/cmd/k8s-operator
         tailscale.com/internal/noiseconn                             from tailscale.com/control/controlclient
         tailscale.com/ipn                                            from tailscale.com/client/local+
         tailscale.com/ipn/conffile                                   from tailscale.com/ipn/ipnlocal+
+     💣 tailscale.com/ipn/desktop                                    from tailscale.com/ipn/ipnlocal+
      💣 tailscale.com/ipn/ipnauth                                    from tailscale.com/ipn/ipnlocal+
         tailscale.com/ipn/ipnlocal                                   from tailscale.com/ipn/localapi+
         tailscale.com/ipn/ipnstate                                   from tailscale.com/client/local+
@@ -994,14 +997,13 @@ tailscale.com/cmd/k8s-operator dependencies: (generated by github.com/tailscale/
         golang.org/x/crypto/cryptobyte                               from crypto/ecdsa+
         golang.org/x/crypto/cryptobyte/asn1                          from crypto/ecdsa+
         golang.org/x/crypto/curve25519                               from golang.org/x/crypto/ssh+
-        golang.org/x/crypto/hkdf                                     from crypto/tls+
+        golang.org/x/crypto/hkdf                                     from tailscale.com/control/controlbase
         golang.org/x/crypto/internal/alias                           from golang.org/x/crypto/chacha20+
         golang.org/x/crypto/internal/poly1305                        from golang.org/x/crypto/chacha20poly1305+
         golang.org/x/crypto/nacl/box                                 from tailscale.com/types/key
         golang.org/x/crypto/nacl/secretbox                           from golang.org/x/crypto/nacl/box
         golang.org/x/crypto/poly1305                                 from github.com/tailscale/wireguard-go/device
         golang.org/x/crypto/salsa20/salsa                            from golang.org/x/crypto/nacl/box+
-        golang.org/x/crypto/sha3                                     from crypto/internal/mlkem768+
   LD    golang.org/x/crypto/ssh                                      from tailscale.com/ipn/ipnlocal
   LD    golang.org/x/crypto/ssh/internal/bcrypt_pbkdf                from golang.org/x/crypto/ssh
         golang.org/x/exp/constraints                                 from github.com/dblohm7/wingoes/pe+
@@ -1052,7 +1054,7 @@ tailscale.com/cmd/k8s-operator dependencies: (generated by github.com/tailscale/
         container/list                                               from crypto/tls+
         context                                                      from crypto/tls+
         crypto                                                       from crypto/ecdh+
-        crypto/aes                                                   from crypto/ecdsa+
+        crypto/aes                                                   from crypto/internal/hpke+
         crypto/cipher                                                from crypto/aes+
         crypto/des                                                   from crypto/tls+
         crypto/dsa                                                   from crypto/x509+
@@ -1061,27 +1063,54 @@ tailscale.com/cmd/k8s-operator dependencies: (generated by github.com/tailscale/
         crypto/ed25519                                               from crypto/tls+
         crypto/elliptic                                              from crypto/ecdsa+
         crypto/hmac                                                  from crypto/tls+
-        crypto/internal/alias                                        from crypto/aes+
-        crypto/internal/bigmod                                       from crypto/ecdsa+
         crypto/internal/boring                                       from crypto/aes+
         crypto/internal/boring/bbig                                  from crypto/ecdsa+
         crypto/internal/boring/sig                                   from crypto/internal/boring
-        crypto/internal/edwards25519                                 from crypto/ed25519
-        crypto/internal/edwards25519/field                           from crypto/ecdh+
+        crypto/internal/entropy                                      from crypto/internal/fips140/drbg
+        crypto/internal/fips140                                      from crypto/internal/fips140/aes+
+        crypto/internal/fips140/aes                                  from crypto/aes+
+        crypto/internal/fips140/aes/gcm                              from crypto/cipher+
+        crypto/internal/fips140/alias                                from crypto/cipher+
+        crypto/internal/fips140/bigmod                               from crypto/internal/fips140/ecdsa+
+        crypto/internal/fips140/check                                from crypto/internal/fips140/aes+
+        crypto/internal/fips140/drbg                                 from crypto/internal/fips140/aes/gcm+
+        crypto/internal/fips140/ecdh                                 from crypto/ecdh
+        crypto/internal/fips140/ecdsa                                from crypto/ecdsa
+        crypto/internal/fips140/ed25519                              from crypto/ed25519
+        crypto/internal/fips140/edwards25519                         from crypto/internal/fips140/ed25519
+        crypto/internal/fips140/edwards25519/field                   from crypto/ecdh+
+        crypto/internal/fips140/hkdf                                 from crypto/internal/fips140/tls13+
+        crypto/internal/fips140/hmac                                 from crypto/hmac+
+        crypto/internal/fips140/mlkem                                from crypto/tls
+        crypto/internal/fips140/nistec                               from crypto/elliptic+
+        crypto/internal/fips140/nistec/fiat                          from crypto/internal/fips140/nistec
+        crypto/internal/fips140/rsa                                  from crypto/rsa
+        crypto/internal/fips140/sha256                               from crypto/internal/fips140/check+
+        crypto/internal/fips140/sha3                                 from crypto/internal/fips140/hmac+
+        crypto/internal/fips140/sha512                               from crypto/internal/fips140/ecdsa+
+        crypto/internal/fips140/subtle                               from crypto/internal/fips140/aes+
+        crypto/internal/fips140/tls12                                from crypto/tls
+        crypto/internal/fips140/tls13                                from crypto/tls
+        crypto/internal/fips140deps/byteorder                        from crypto/internal/fips140/aes+
+        crypto/internal/fips140deps/cpu                              from crypto/internal/fips140/aes+
+        crypto/internal/fips140deps/godebug                          from crypto/internal/fips140+
+        crypto/internal/fips140hash                                  from crypto/ecdsa+
+        crypto/internal/fips140only                                  from crypto/cipher+
         crypto/internal/hpke                                         from crypto/tls
-        crypto/internal/mlkem768                                     from crypto/tls
-        crypto/internal/nistec                                       from crypto/ecdh+
-        crypto/internal/nistec/fiat                                  from crypto/internal/nistec
+        crypto/internal/impl                                         from crypto/internal/fips140/aes+
         crypto/internal/randutil                                     from crypto/dsa+
+        crypto/internal/sysrand                                      from crypto/internal/entropy+
         crypto/md5                                                   from crypto/tls+
         crypto/rand                                                  from crypto/ed25519+
         crypto/rc4                                                   from crypto/tls+
         crypto/rsa                                                   from crypto/tls+
         crypto/sha1                                                  from crypto/tls+
         crypto/sha256                                                from crypto/tls+
+        crypto/sha3                                                  from crypto/internal/fips140hash
         crypto/sha512                                                from crypto/ecdsa+
-        crypto/subtle                                                from crypto/aes+
+        crypto/subtle                                                from crypto/cipher+
         crypto/tls                                                   from github.com/aws/aws-sdk-go-v2/aws/transport/http+
+        crypto/tls/internal/fips140tls                               from crypto/tls
         crypto/x509                                                  from crypto/tls+
    D    crypto/x509/internal/macos                                   from crypto/x509
         crypto/x509/pkix                                             from crypto/x509+
@@ -1089,7 +1118,7 @@ tailscale.com/cmd/k8s-operator dependencies: (generated by github.com/tailscale/
         database/sql/driver                                          from database/sql+
    W    debug/dwarf                                                  from debug/pe
    W    debug/pe                                                     from github.com/dblohm7/wingoes/pe
-        embed                                                        from crypto/internal/nistec+
+        embed                                                        from github.com/tailscale/web-client-prebuilt+
         encoding                                                     from encoding/gob+
         encoding/asn1                                                from crypto/x509+
         encoding/base32                                              from github.com/fxamacker/cbor/v2+
@@ -1109,7 +1138,6 @@ tailscale.com/cmd/k8s-operator dependencies: (generated by github.com/tailscale/
         go/build/constraint                                          from go/parser
         go/doc                                                       from k8s.io/apimachinery/pkg/runtime
         go/doc/comment                                               from go/doc
-        go/internal/typeparams                                       from go/parser
         go/parser                                                    from k8s.io/apimachinery/pkg/runtime
         go/scanner                                                   from go/ast+
         go/token                                                     from go/ast+
@@ -1121,24 +1149,23 @@ tailscale.com/cmd/k8s-operator dependencies: (generated by github.com/tailscale/
         html                                                         from html/template+
         html/template                                                from github.com/gorilla/csrf
         internal/abi                                                 from crypto/x509/internal/macos+
-        internal/asan                                                from syscall
+        internal/asan                                                from syscall+
         internal/bisect                                              from internal/godebug
         internal/bytealg                                             from bytes+
-        internal/byteorder                                           from crypto/aes+
+        internal/byteorder                                           from crypto/cipher+
         internal/chacha8rand                                         from math/rand/v2+
-        internal/concurrent                                          from unique
         internal/coverage/rtcov                                      from runtime
-        internal/cpu                                                 from crypto/aes+
+        internal/cpu                                                 from crypto/internal/fips140deps/cpu+
         internal/filepathlite                                        from os+
         internal/fmtsort                                             from fmt+
-        internal/goarch                                              from crypto/aes+
+        internal/goarch                                              from crypto/internal/fips140deps/cpu+
         internal/godebug                                             from archive/tar+
         internal/godebugs                                            from internal/godebug+
-        internal/goexperiment                                        from runtime
+        internal/goexperiment                                        from runtime+
         internal/goos                                                from crypto/x509+
         internal/itoa                                                from internal/poll+
         internal/lazyregexp                                          from go/doc
-        internal/msan                                                from syscall
+        internal/msan                                                from syscall+
         internal/nettrace                                            from net+
         internal/oserror                                             from io/fs+
         internal/poll                                                from net+
@@ -1148,18 +1175,21 @@ tailscale.com/cmd/k8s-operator dependencies: (generated by github.com/tailscale/
         internal/reflectlite                                         from context+
         internal/runtime/atomic                                      from internal/runtime/exithook+
         internal/runtime/exithook                                    from runtime
+        internal/runtime/maps                                        from reflect+
+        internal/runtime/math                                        from internal/runtime/maps+
+        internal/runtime/sys                                         from crypto/subtle+
    L    internal/runtime/syscall                                     from runtime+
         internal/saferio                                             from debug/pe+
         internal/singleflight                                        from net
         internal/stringslite                                         from embed+
+        internal/sync                                                from sync+
         internal/syscall/execenv                                     from os+
-  LD    internal/syscall/unix                                        from crypto/rand+
-   W    internal/syscall/windows                                     from crypto/rand+
+  LD    internal/syscall/unix                                        from crypto/internal/sysrand+
+   W    internal/syscall/windows                                     from crypto/internal/sysrand+
    W    internal/syscall/windows/registry                            from mime+
    W    internal/syscall/windows/sysdll                              from internal/syscall/windows+
         internal/testlog                                             from os
         internal/unsafeheader                                        from internal/reflectlite+
-        internal/weak                                                from unique
         io                                                           from archive/tar+
         io/fs                                                        from archive/tar+
         io/ioutil                                                    from github.com/aws/aws-sdk-go-v2/aws/protocol/query+
@@ -1188,7 +1218,7 @@ tailscale.com/cmd/k8s-operator dependencies: (generated by github.com/tailscale/
         net/netip                                                    from github.com/gaissmai/bart+
         net/textproto                                                from github.com/aws/aws-sdk-go-v2/aws/signer/v4+
         net/url                                                      from crypto/x509+
-        os                                                           from crypto/rand+
+        os                                                           from crypto/internal/sysrand+
         os/exec                                                      from github.com/aws/aws-sdk-go-v2/credentials/processcreds+
         os/signal                                                    from sigs.k8s.io/controller-runtime/pkg/manager/signals
         os/user                                                      from archive/tar+
@@ -1199,8 +1229,6 @@ tailscale.com/cmd/k8s-operator dependencies: (generated by github.com/tailscale/
         regexp/syntax                                                from regexp
         runtime                                                      from archive/tar+
         runtime/debug                                                from github.com/aws/aws-sdk-go-v2/internal/sync/singleflight+
-        runtime/internal/math                                        from runtime
-        runtime/internal/sys                                         from runtime
         runtime/metrics                                              from github.com/prometheus/client_golang/prometheus+
         runtime/pprof                                                from net/http/pprof+
         runtime/trace                                                from net/http/pprof
@@ -1220,3 +1248,4 @@ tailscale.com/cmd/k8s-operator dependencies: (generated by github.com/tailscale/
         unicode/utf8                                                 from bufio+
         unique                                                       from net/netip
         unsafe                                                       from bytes+
+        weak                                                         from unique

cmd/k8s-operator/e2e/main_test.go

@@ -21,7 +21,7 @@ import (
 	"sigs.k8s.io/controller-runtime/pkg/client"
 	logf "sigs.k8s.io/controller-runtime/pkg/log"
 	kzap "sigs.k8s.io/controller-runtime/pkg/log/zap"
-	"tailscale.com/client/tailscale"
+	"tailscale.com/internal/client/tailscale"
 )
 
 const (
@@ -64,7 +64,6 @@ func TestMain(m *testing.M) {
 func runTests(m *testing.M) (int, error) {
 	zlog := kzap.NewRaw([]kzap.Opts{kzap.UseDevMode(true), kzap.Level(zapcore.DebugLevel)}...).Sugar()
 	logf.SetLogger(zapr.NewLogger(zlog.Desugar()))
-	tailscale.I_Acknowledge_This_API_Is_Unstable = true
 
 	if clientID := os.Getenv("TS_API_CLIENT_ID"); clientID != "" {
 		cleanup, err := setupClientAndACLs()

cmd/k8s-operator/ingress-for-pg.go

@@ -26,7 +26,7 @@ import (
 	"k8s.io/client-go/tools/record"
 	"sigs.k8s.io/controller-runtime/pkg/client"
 	"sigs.k8s.io/controller-runtime/pkg/reconcile"
-	"tailscale.com/client/tailscale"
+	"tailscale.com/internal/client/tailscale"
 	"tailscale.com/ipn"
 	"tailscale.com/ipn/ipnstate"
 	tsoperator "tailscale.com/k8s-operator"
@@ -46,6 +46,9 @@ const (
 	FinalizerNamePG = "tailscale.com/ingress-pg-finalizer"
 
 	indexIngressProxyGroup = ".metadata.annotations.ingress-proxy-group"
+	// annotationHTTPEndpoint can be used to configure the Ingress to expose an HTTP endpoint to tailnet (as
+	// well as the default HTTPS endpoint).
+	annotationHTTPEndpoint = "tailscale.com/http-endpoint"
 )
 
 var gaugePGIngressResources = clientmetric.NewGauge(kubetypes.MetricIngressPGResourceCount)
@@ -183,7 +186,7 @@ func (a *IngressPGReconciler) maybeProvision(ctx context.Context, hostname strin
 	}
 	dnsName := hostname + "." + tcd
 	serviceName := tailcfg.ServiceName("svc:" + hostname)
-	existingVIPSvc, err := a.tsClient.getVIPService(ctx, serviceName)
+	existingVIPSvc, err := a.tsClient.GetVIPService(ctx, serviceName)
 	// TODO(irbekrm): here and when creating the VIPService, verify if the error is not terminal (and therefore
 	// should not be reconciled). For example, if the hostname is already a hostname of a Tailscale node, the GET
 	// here will fail.
@@ -202,16 +205,16 @@ func (a *IngressPGReconciler) maybeProvision(ctx context.Context, hostname strin
 	// 3. Ensure that the serve config for the ProxyGroup contains the VIPService
 	cm, cfg, err := a.proxyGroupServeConfig(ctx, pgName)
 	if err != nil {
-		return fmt.Errorf("error getting ingress serve config: %w", err)
+		return fmt.Errorf("error getting Ingress serve config: %w", err)
 	}
 	if cm == nil {
-		logger.Infof("no ingress serve config ConfigMap found, unable to update serve config. Ensure that ProxyGroup is healthy.")
+		logger.Infof("no Ingress serve config ConfigMap found, unable to update serve config. Ensure that ProxyGroup is healthy.")
 		return nil
 	}
 	ep := ipn.HostPort(fmt.Sprintf("%s:443", dnsName))
 	handlers, err := handlersForIngress(ctx, ing, a.Client, a.recorder, dnsName, logger)
 	if err != nil {
-		return fmt.Errorf("failed to get handlers for ingress: %w", err)
+		return fmt.Errorf("failed to get handlers for Ingress: %w", err)
 	}
 	ingCfg := &ipn.ServiceConfig{
 		TCP: map[uint16]*ipn.TCPPortHandler{
@@ -225,6 +228,19 @@ func (a *IngressPGReconciler) maybeProvision(ctx context.Context, hostname strin
 			},
 		},
 	}
+
+	// Add HTTP endpoint if configured.
+	if isHTTPEndpointEnabled(ing) {
+		logger.Infof("exposing Ingress over HTTP")
+		epHTTP := ipn.HostPort(fmt.Sprintf("%s:80", dnsName))
+		ingCfg.TCP[80] = &ipn.TCPPortHandler{
+			HTTP: true,
+		}
+		ingCfg.Web[epHTTP] = &ipn.WebServerConfig{
+			Handlers: handlers,
+		}
+	}
+
 	var gotCfg *ipn.ServiceConfig
 	if cfg != nil && cfg.Services != nil {
 		gotCfg = cfg.Services[serviceName]
@@ -248,18 +264,25 @@ func (a *IngressPGReconciler) maybeProvision(ctx context.Context, hostname strin
 		tags = strings.Split(tstr, ",")
 	}
 
-	vipSvc := &VIPService{
+	vipPorts := []string{"443"} // always 443 for Ingress
+	if isHTTPEndpointEnabled(ing) {
+		vipPorts = append(vipPorts, "80")
+	}
+
+	vipSvc := &tailscale.VIPService{
 		Name:    serviceName,
 		Tags:    tags,
-		Ports:   []string{"443"}, // always 443 for Ingress
+		Ports:   vipPorts,
 		Comment: fmt.Sprintf(VIPSvcOwnerRef, ing.UID),
 	}
 	if existingVIPSvc != nil {
 		vipSvc.Addrs = existingVIPSvc.Addrs
 	}
-	if existingVIPSvc == nil || !reflect.DeepEqual(vipSvc.Tags, existingVIPSvc.Tags) {
+	if existingVIPSvc == nil ||
+		!reflect.DeepEqual(vipSvc.Tags, existingVIPSvc.Tags) ||
+		!reflect.DeepEqual(vipSvc.Ports, existingVIPSvc.Ports) {
 		logger.Infof("Ensuring VIPService %q exists and is up to date", hostname)
-		if err := a.tsClient.createOrUpdateVIPService(ctx, vipSvc); err != nil {
+		if err := a.tsClient.CreateOrUpdateVIPService(ctx, vipSvc); err != nil {
 			logger.Infof("error creating VIPService: %v", err)
 			return fmt.Errorf("error creating VIPService: %w", err)
 		}
@@ -267,16 +290,22 @@ func (a *IngressPGReconciler) maybeProvision(ctx context.Context, hostname strin
 
 	// 5. Update Ingress status
 	oldStatus := ing.Status.DeepCopy()
-	// TODO(irbekrm): once we have ingress ProxyGroup, we can determine if instances are ready to route traffic to the VIPService
+	ports := []networkingv1.IngressPortStatus{
+		{
+			Protocol: "TCP",
+			Port:     443,
+		},
+	}
+	if isHTTPEndpointEnabled(ing) {
+		ports = append(ports, networkingv1.IngressPortStatus{
+			Protocol: "TCP",
+			Port:     80,
+		})
+	}
 	ing.Status.LoadBalancer.Ingress = []networkingv1.IngressLoadBalancerIngress{
 		{
 			Hostname: dnsName,
-			Ports: []networkingv1.IngressPortStatus{
-				{
-					Protocol: "TCP",
-					Port:     443,
-				},
-			},
+			Ports:    ports,
 		},
 	}
 	if apiequality.Semantic.DeepEqual(oldStatus, ing.Status) {
@@ -332,7 +361,7 @@ func (a *IngressPGReconciler) maybeCleanupProxyGroup(ctx context.Context, proxyG
 			}
 			if isVIPServiceForAnyIngress(svc) {
 				logger.Infof("cleaning up orphaned VIPService %q", vipServiceName)
-				if err := a.tsClient.deleteVIPService(ctx, vipServiceName); err != nil {
+				if err := a.tsClient.DeleteVIPService(ctx, vipServiceName); err != nil {
 					errResp := &tailscale.ErrResponse{}
 					if !errors.As(err, &errResp) || errResp.Status != http.StatusNotFound {
 						return fmt.Errorf("deleting VIPService %q: %w", vipServiceName, err)
@@ -480,8 +509,8 @@ func (a *IngressPGReconciler) shouldExpose(ing *networkingv1.Ingress) bool {
 	return isTSIngress && pgAnnot != ""
 }
 
-func (a *IngressPGReconciler) getVIPService(ctx context.Context, name tailcfg.ServiceName, logger *zap.SugaredLogger) (*VIPService, error) {
-	svc, err := a.tsClient.getVIPService(ctx, name)
+func (a *IngressPGReconciler) getVIPService(ctx context.Context, name tailcfg.ServiceName, logger *zap.SugaredLogger) (*tailscale.VIPService, error) {
+	svc, err := a.tsClient.GetVIPService(ctx, name)
 	if err != nil {
 		errResp := &tailscale.ErrResponse{}
 		if ok := errors.As(err, errResp); ok && errResp.Status != http.StatusNotFound {
@@ -492,14 +521,14 @@ func (a *IngressPGReconciler) getVIPService(ctx context.Context, name tailcfg.Se
 	return svc, nil
 }
 
-func isVIPServiceForIngress(svc *VIPService, ing *networkingv1.Ingress) bool {
+func isVIPServiceForIngress(svc *tailscale.VIPService, ing *networkingv1.Ingress) bool {
 	if svc == nil || ing == nil {
 		return false
 	}
 	return strings.EqualFold(svc.Comment, fmt.Sprintf(VIPSvcOwnerRef, ing.UID))
 }
 
-func isVIPServiceForAnyIngress(svc *VIPService) bool {
+func isVIPServiceForAnyIngress(svc *tailscale.VIPService) bool {
 	if svc == nil {
 		return false
 	}
@@ -564,8 +593,16 @@ func (a *IngressPGReconciler) deleteVIPServiceIfExists(ctx context.Context, name
 	}
 
 	logger.Infof("Deleting VIPService %q", name)
-	if err = a.tsClient.deleteVIPService(ctx, name); err != nil {
+	if err = a.tsClient.DeleteVIPService(ctx, name); err != nil {
 		return fmt.Errorf("error deleting VIPService: %w", err)
 	}
 	return nil
 }
+
+// isHTTPEndpointEnabled returns true if the Ingress has been configured to expose an HTTP endpoint to tailnet.
+func isHTTPEndpointEnabled(ing *networkingv1.Ingress) bool {
+	if ing == nil {
+		return false
+	}
+	return ing.Annotations[annotationHTTPEndpoint] == "enabled"
+}

cmd/k8s-operator/ingress-for-pg_test.go

@@ -8,6 +8,8 @@ package main
 import (
 	"context"
 	"encoding/json"
+	"maps"
+	"reflect"
 	"testing"
 
 	"slices"
@@ -18,81 +20,18 @@ import (
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/types"
 	"k8s.io/client-go/tools/record"
+	"sigs.k8s.io/controller-runtime/pkg/client"
 	"sigs.k8s.io/controller-runtime/pkg/client/fake"
 	"tailscale.com/ipn"
 	"tailscale.com/ipn/ipnstate"
 	tsapi "tailscale.com/k8s-operator/apis/v1alpha1"
+	"tailscale.com/tailcfg"
 	"tailscale.com/types/ptr"
 )
 
 func TestIngressPGReconciler(t *testing.T) {
-	tsIngressClass := &networkingv1.IngressClass{
-		ObjectMeta: metav1.ObjectMeta{Name: "tailscale"},
-		Spec:       networkingv1.IngressClassSpec{Controller: "tailscale.com/ts-ingress"},
-	}
+	ingPGR, fc, ft := setupIngressTest(t)
 
-	// Pre-create the ProxyGroup
-	pg := &tsapi.ProxyGroup{
-		ObjectMeta: metav1.ObjectMeta{
-			Name:       "test-pg",
-			Generation: 1,
-		},
-		Spec: tsapi.ProxyGroupSpec{
-			Type: tsapi.ProxyGroupTypeIngress,
-		},
-	}
-
-	// Pre-create the ConfigMap for the ProxyGroup
-	pgConfigMap := &corev1.ConfigMap{
-		ObjectMeta: metav1.ObjectMeta{
-			Name:      "test-pg-ingress-config",
-			Namespace: "operator-ns",
-		},
-		BinaryData: map[string][]byte{
-			"serve-config.json": []byte(`{"Services":{}}`),
-		},
-	}
-
-	fc := fake.NewClientBuilder().
-		WithScheme(tsapi.GlobalScheme).
-		WithObjects(pg, pgConfigMap, tsIngressClass).
-		WithStatusSubresource(pg).
-		Build()
-	mustUpdateStatus(t, fc, "", pg.Name, func(pg *tsapi.ProxyGroup) {
-		pg.Status.Conditions = []metav1.Condition{
-			{
-				Type:               string(tsapi.ProxyGroupReady),
-				Status:             metav1.ConditionTrue,
-				ObservedGeneration: 1,
-			},
-		}
-	})
-	ft := &fakeTSClient{}
-	fakeTsnetServer := &fakeTSNetServer{certDomains: []string{"foo.com"}}
-	zl, err := zap.NewDevelopment()
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	lc := &fakeLocalClient{
-		status: &ipnstate.Status{
-			CurrentTailnet: &ipnstate.TailnetStatus{
-				MagicDNSSuffix: "ts.net",
-			},
-		},
-	}
-	ingPGR := &IngressPGReconciler{
-		Client:      fc,
-		tsClient:    ft,
-		tsnetServer: fakeTsnetServer,
-		defaultTags: []string{"tag:k8s"},
-		tsNamespace: "operator-ns",
-		logger:      zl.Sugar(),
-		recorder:    record.NewFakeRecorder(10),
-		lc:          lc,
-	}
-
-	// Test 1: Default tags
 	ing := &networkingv1.Ingress{
 		TypeMeta: metav1.TypeMeta{Kind: "Ingress", APIVersion: "networking.k8s.io/v1"},
 		ObjectMeta: metav1.ObjectMeta{
@@ -122,8 +61,74 @@ func TestIngressPGReconciler(t *testing.T) {
 
 	// Verify initial reconciliation
 	expectReconciled(t, ingPGR, "default", "test-ingress")
+	verifyServeConfig(t, fc, "svc:my-svc", false)
+	verifyVIPService(t, ft, "svc:my-svc", []string{"443"})
 
-	// Get and verify the ConfigMap was updated
+	mustUpdate(t, fc, "default", "test-ingress", func(ing *networkingv1.Ingress) {
+		ing.Annotations["tailscale.com/tags"] = "tag:custom,tag:test"
+	})
+	expectReconciled(t, ingPGR, "default", "test-ingress")
+
+	// Verify VIPService uses custom tags
+	vipSvc, err := ft.GetVIPService(context.Background(), "svc:my-svc")
+	if err != nil {
+		t.Fatalf("getting VIPService: %v", err)
+	}
+	if vipSvc == nil {
+		t.Fatal("VIPService not created")
+	}
+	wantTags := []string{"tag:custom", "tag:test"} // custom tags only
+	gotTags := slices.Clone(vipSvc.Tags)
+	slices.Sort(gotTags)
+	slices.Sort(wantTags)
+	if !slices.Equal(gotTags, wantTags) {
+		t.Errorf("incorrect VIPService tags: got %v, want %v", gotTags, wantTags)
+	}
+
+	// Create second Ingress
+	ing2 := &networkingv1.Ingress{
+		TypeMeta: metav1.TypeMeta{Kind: "Ingress", APIVersion: "networking.k8s.io/v1"},
+		ObjectMeta: metav1.ObjectMeta{
+			Name:      "my-other-ingress",
+			Namespace: "default",
+			UID:       types.UID("5678-UID"),
+			Annotations: map[string]string{
+				"tailscale.com/proxy-group": "test-pg",
+			},
+		},
+		Spec: networkingv1.IngressSpec{
+			IngressClassName: ptr.To("tailscale"),
+			DefaultBackend: &networkingv1.IngressBackend{
+				Service: &networkingv1.IngressServiceBackend{
+					Name: "test",
+					Port: networkingv1.ServiceBackendPort{
+						Number: 8080,
+					},
+				},
+			},
+			TLS: []networkingv1.IngressTLS{
+				{Hosts: []string{"my-other-svc.tailnetxyz.ts.net"}},
+			},
+		},
+	}
+	mustCreate(t, fc, ing2)
+
+	// Verify second Ingress reconciliation
+	expectReconciled(t, ingPGR, "default", "my-other-ingress")
+	verifyServeConfig(t, fc, "svc:my-other-svc", false)
+	verifyVIPService(t, ft, "svc:my-other-svc", []string{"443"})
+
+	// Verify first Ingress is still working
+	verifyServeConfig(t, fc, "svc:my-svc", false)
+	verifyVIPService(t, ft, "svc:my-svc", []string{"443"})
+
+	// Delete second Ingress
+	if err := fc.Delete(context.Background(), ing2); err != nil {
+		t.Fatalf("deleting second Ingress: %v", err)
+	}
+	expectReconciled(t, ingPGR, "default", "my-other-ingress")
+
+	// Verify second Ingress cleanup
 	cm := &corev1.ConfigMap{}
 	if err := fc.Get(context.Background(), types.NamespacedName{
 		Name:      "test-pg-ingress-config",
@@ -137,46 +142,16 @@ func TestIngressPGReconciler(t *testing.T) {
 		t.Fatalf("unmarshaling serve config: %v", err)
 	}
 
+	// Verify first Ingress is still configured
 	if cfg.Services["svc:my-svc"] == nil {
-		t.Error("expected serve config to contain VIPService configuration")
+		t.Error("first Ingress service config was incorrectly removed")
+	}
+	// Verify second Ingress was cleaned up
+	if cfg.Services["svc:my-other-svc"] != nil {
+		t.Error("second Ingress service config was not cleaned up")
 	}
 
-	// Verify VIPService uses default tags
-	vipSvc, err := ft.getVIPService(context.Background(), "svc:my-svc")
-	if err != nil {
-		t.Fatalf("getting VIPService: %v", err)
-	}
-	if vipSvc == nil {
-		t.Fatal("VIPService not created")
-	}
-	wantTags := []string{"tag:k8s"} // default tags
-	if !slices.Equal(vipSvc.Tags, wantTags) {
-		t.Errorf("incorrect VIPService tags: got %v, want %v", vipSvc.Tags, wantTags)
-	}
-
-	// Test 2: Custom tags
-	mustUpdate(t, fc, "default", "test-ingress", func(ing *networkingv1.Ingress) {
-		ing.Annotations["tailscale.com/tags"] = "tag:custom,tag:test"
-	})
-	expectReconciled(t, ingPGR, "default", "test-ingress")
-
-	// Verify VIPService uses custom tags
-	vipSvc, err = ft.getVIPService(context.Background(), "svc:my-svc")
-	if err != nil {
-		t.Fatalf("getting VIPService: %v", err)
-	}
-	if vipSvc == nil {
-		t.Fatal("VIPService not created")
-	}
-	wantTags = []string{"tag:custom", "tag:test"} // custom tags only
-	gotTags := slices.Clone(vipSvc.Tags)
-	slices.Sort(gotTags)
-	slices.Sort(wantTags)
-	if !slices.Equal(gotTags, wantTags) {
-		t.Errorf("incorrect VIPService tags: got %v, want %v", gotTags, wantTags)
-	}
-
-	// Delete the Ingress and verify cleanup
+	// Delete the first Ingress and verify cleanup
 	if err := fc.Delete(context.Background(), ing); err != nil {
 		t.Fatalf("deleting Ingress: %v", err)
 	}
@@ -335,3 +310,233 @@ func TestValidateIngress(t *testing.T) {
 		})
 	}
 }
+
+func TestIngressPGReconciler_HTTPEndpoint(t *testing.T) {
+	ingPGR, fc, ft := setupIngressTest(t)
+
+	// Create test Ingress with HTTP endpoint enabled
+	ing := &networkingv1.Ingress{
+		TypeMeta: metav1.TypeMeta{Kind: "Ingress", APIVersion: "networking.k8s.io/v1"},
+		ObjectMeta: metav1.ObjectMeta{
+			Name:      "test-ingress",
+			Namespace: "default",
+			UID:       types.UID("1234-UID"),
+			Annotations: map[string]string{
+				"tailscale.com/proxy-group":   "test-pg",
+				"tailscale.com/http-endpoint": "enabled",
+			},
+		},
+		Spec: networkingv1.IngressSpec{
+			IngressClassName: ptr.To("tailscale"),
+			DefaultBackend: &networkingv1.IngressBackend{
+				Service: &networkingv1.IngressServiceBackend{
+					Name: "test",
+					Port: networkingv1.ServiceBackendPort{
+						Number: 8080,
+					},
+				},
+			},
+			TLS: []networkingv1.IngressTLS{
+				{Hosts: []string{"my-svc"}},
+			},
+		},
+	}
+	if err := fc.Create(context.Background(), ing); err != nil {
+		t.Fatal(err)
+	}
+
+	// Verify initial reconciliation with HTTP enabled
+	expectReconciled(t, ingPGR, "default", "test-ingress")
+	verifyVIPService(t, ft, "svc:my-svc", []string{"80", "443"})
+	verifyServeConfig(t, fc, "svc:my-svc", true)
+
+	// Verify Ingress status
+	ing = &networkingv1.Ingress{}
+	if err := fc.Get(context.Background(), types.NamespacedName{
+		Name:      "test-ingress",
+		Namespace: "default",
+	}, ing); err != nil {
+		t.Fatal(err)
+	}
+
+	wantStatus := []networkingv1.IngressPortStatus{
+		{Port: 443, Protocol: "TCP"},
+		{Port: 80, Protocol: "TCP"},
+	}
+	if !reflect.DeepEqual(ing.Status.LoadBalancer.Ingress[0].Ports, wantStatus) {
+		t.Errorf("incorrect status ports: got %v, want %v",
+			ing.Status.LoadBalancer.Ingress[0].Ports, wantStatus)
+	}
+
+	// Remove HTTP endpoint annotation
+	mustUpdate(t, fc, "default", "test-ingress", func(ing *networkingv1.Ingress) {
+		delete(ing.Annotations, "tailscale.com/http-endpoint")
+	})
+
+	// Verify reconciliation after removing HTTP
+	expectReconciled(t, ingPGR, "default", "test-ingress")
+	verifyVIPService(t, ft, "svc:my-svc", []string{"443"})
+	verifyServeConfig(t, fc, "svc:my-svc", false)
+
+	// Verify Ingress status
+	ing = &networkingv1.Ingress{}
+	if err := fc.Get(context.Background(), types.NamespacedName{
+		Name:      "test-ingress",
+		Namespace: "default",
+	}, ing); err != nil {
+		t.Fatal(err)
+	}
+
+	wantStatus = []networkingv1.IngressPortStatus{
+		{Port: 443, Protocol: "TCP"},
+	}
+	if !reflect.DeepEqual(ing.Status.LoadBalancer.Ingress[0].Ports, wantStatus) {
+		t.Errorf("incorrect status ports: got %v, want %v",
+			ing.Status.LoadBalancer.Ingress[0].Ports, wantStatus)
+	}
+}
+
+func verifyVIPService(t *testing.T, ft *fakeTSClient, serviceName string, wantPorts []string) {
+	t.Helper()
+	vipSvc, err := ft.GetVIPService(context.Background(), tailcfg.ServiceName(serviceName))
+	if err != nil {
+		t.Fatalf("getting VIPService %q: %v", serviceName, err)
+	}
+	if vipSvc == nil {
+		t.Fatalf("VIPService %q not created", serviceName)
+	}
+	gotPorts := slices.Clone(vipSvc.Ports)
+	slices.Sort(gotPorts)
+	slices.Sort(wantPorts)
+	if !slices.Equal(gotPorts, wantPorts) {
+		t.Errorf("incorrect ports for VIPService %q: got %v, want %v", serviceName, gotPorts, wantPorts)
+	}
+}
+
+func verifyServeConfig(t *testing.T, fc client.Client, serviceName string, wantHTTP bool) {
+	t.Helper()
+
+	cm := &corev1.ConfigMap{}
+	if err := fc.Get(context.Background(), types.NamespacedName{
+		Name:      "test-pg-ingress-config",
+		Namespace: "operator-ns",
+	}, cm); err != nil {
+		t.Fatalf("getting ConfigMap: %v", err)
+	}
+
+	cfg := &ipn.ServeConfig{}
+	if err := json.Unmarshal(cm.BinaryData["serve-config.json"], cfg); err != nil {
+		t.Fatalf("unmarshaling serve config: %v", err)
+	}
+
+	t.Logf("Looking for service %q in config: %+v", serviceName, cfg)
+
+	svc := cfg.Services[tailcfg.ServiceName(serviceName)]
+	if svc == nil {
+		t.Fatalf("service %q not found in serve config, services: %+v", serviceName, maps.Keys(cfg.Services))
+	}
+
+	wantHandlers := 1
+	if wantHTTP {
+		wantHandlers = 2
+	}
+
+	// Check TCP handlers
+	if len(svc.TCP) != wantHandlers {
+		t.Errorf("incorrect number of TCP handlers for service %q: got %d, want %d", serviceName, len(svc.TCP), wantHandlers)
+	}
+	if wantHTTP {
+		if h, ok := svc.TCP[uint16(80)]; !ok {
+			t.Errorf("HTTP (port 80) handler not found for service %q", serviceName)
+		} else if !h.HTTP {
+			t.Errorf("HTTP not enabled for port 80 handler for service %q", serviceName)
+		}
+	}
+	if h, ok := svc.TCP[uint16(443)]; !ok {
+		t.Errorf("HTTPS (port 443) handler not found for service %q", serviceName)
+	} else if !h.HTTPS {
+		t.Errorf("HTTPS not enabled for port 443 handler for service %q", serviceName)
+	}
+
+	// Check Web handlers
+	if len(svc.Web) != wantHandlers {
+		t.Errorf("incorrect number of Web handlers for service %q: got %d, want %d", serviceName, len(svc.Web), wantHandlers)
+	}
+}
+
+func setupIngressTest(t *testing.T) (*IngressPGReconciler, client.Client, *fakeTSClient) {
+	t.Helper()
+
+	tsIngressClass := &networkingv1.IngressClass{
+		ObjectMeta: metav1.ObjectMeta{Name: "tailscale"},
+		Spec:       networkingv1.IngressClassSpec{Controller: "tailscale.com/ts-ingress"},
+	}
+
+	// Pre-create the ProxyGroup
+	pg := &tsapi.ProxyGroup{
+		ObjectMeta: metav1.ObjectMeta{
+			Name:       "test-pg",
+			Generation: 1,
+		},
+		Spec: tsapi.ProxyGroupSpec{
+			Type: tsapi.ProxyGroupTypeIngress,
+		},
+	}
+
+	// Pre-create the ConfigMap for the ProxyGroup
+	pgConfigMap := &corev1.ConfigMap{
+		ObjectMeta: metav1.ObjectMeta{
+			Name:      "test-pg-ingress-config",
+			Namespace: "operator-ns",
+		},
+		BinaryData: map[string][]byte{
+			"serve-config.json": []byte(`{"Services":{}}`),
+		},
+	}
+
+	fc := fake.NewClientBuilder().
+		WithScheme(tsapi.GlobalScheme).
+		WithObjects(pg, pgConfigMap, tsIngressClass).
+		WithStatusSubresource(pg).
+		Build()
+
+	// Set ProxyGroup status to ready
+	pg.Status.Conditions = []metav1.Condition{
+		{
+			Type:               string(tsapi.ProxyGroupReady),
+			Status:             metav1.ConditionTrue,
+			ObservedGeneration: 1,
+		},
+	}
+	if err := fc.Status().Update(context.Background(), pg); err != nil {
+		t.Fatal(err)
+	}
+
+	ft := &fakeTSClient{}
+	fakeTsnetServer := &fakeTSNetServer{certDomains: []string{"foo.com"}}
+	zl, err := zap.NewDevelopment()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	lc := &fakeLocalClient{
+		status: &ipnstate.Status{
+			CurrentTailnet: &ipnstate.TailnetStatus{
+				MagicDNSSuffix: "ts.net",
+			},
+		},
+	}
+
+	ingPGR := &IngressPGReconciler{
+		Client:      fc,
+		tsClient:    ft,
+		tsnetServer: fakeTsnetServer,
+		defaultTags: []string{"tag:k8s"},
+		tsNamespace: "operator-ns",
+		logger:      zl.Sugar(),
+		recorder:    record.NewFakeRecorder(10),
+		lc:          lc,
+	}
+
+	return ingPGR, fc, ft
+}

cmd/k8s-operator/testutils_test.go

@@ -28,7 +28,7 @@ import (
 	"k8s.io/client-go/tools/record"
 	"sigs.k8s.io/controller-runtime/pkg/client"
 	"sigs.k8s.io/controller-runtime/pkg/reconcile"
-	"tailscale.com/client/tailscale"
+	"tailscale.com/internal/client/tailscale"
 	"tailscale.com/ipn"
 	"tailscale.com/ipn/ipnstate"
 	tsapi "tailscale.com/k8s-operator/apis/v1alpha1"
@@ -768,7 +768,7 @@ type fakeTSClient struct {
 	sync.Mutex
 	keyRequests []tailscale.KeyCapabilities
 	deleted     []string
-	vipServices map[tailcfg.ServiceName]*VIPService
+	vipServices map[tailcfg.ServiceName]*tailscale.VIPService
 }
 type fakeTSNetServer struct {
 	certDomains []string
@@ -875,7 +875,7 @@ func removeAuthKeyIfExistsModifier(t *testing.T) func(s *corev1.Secret) {
 	}
 }
 
-func (c *fakeTSClient) getVIPService(ctx context.Context, name tailcfg.ServiceName) (*VIPService, error) {
+func (c *fakeTSClient) GetVIPService(ctx context.Context, name tailcfg.ServiceName) (*tailscale.VIPService, error) {
 	c.Lock()
 	defer c.Unlock()
 	if c.vipServices == nil {
@@ -888,17 +888,17 @@ func (c *fakeTSClient) getVIPService(ctx context.Context, name tailcfg.ServiceNa
 	return svc, nil
 }
 
-func (c *fakeTSClient) createOrUpdateVIPService(ctx context.Context, svc *VIPService) error {
+func (c *fakeTSClient) CreateOrUpdateVIPService(ctx context.Context, svc *tailscale.VIPService) error {
 	c.Lock()
 	defer c.Unlock()
 	if c.vipServices == nil {
-		c.vipServices = make(map[tailcfg.ServiceName]*VIPService)
+		c.vipServices = make(map[tailcfg.ServiceName]*tailscale.VIPService)
 	}
 	c.vipServices[svc.Name] = svc
 	return nil
 }
 
-func (c *fakeTSClient) deleteVIPService(ctx context.Context, name tailcfg.ServiceName) error {
+func (c *fakeTSClient) DeleteVIPService(ctx context.Context, name tailcfg.ServiceName) error {
 	c.Lock()
 	defer c.Unlock()
 	if c.vipServices != nil {

cmd/k8s-operator/tsclient.go

@@ -6,19 +6,13 @@
 package main
 
 import (
-	"bytes"
 	"context"
-	"encoding/json"
 	"fmt"
-	"io"
-	"net/http"
-	"net/url"
 	"os"
 
 	"golang.org/x/oauth2/clientcredentials"
-	"tailscale.com/client/tailscale"
+	"tailscale.com/internal/client/tailscale"
 	"tailscale.com/tailcfg"
-	"tailscale.com/util/httpm"
 )
 
 // defaultTailnet is a value that can be used in Tailscale API calls instead of tailnet name to indicate that the API
@@ -45,141 +39,14 @@ func newTSClient(ctx context.Context, clientIDPath, clientSecretPath string) (ts
 	c := tailscale.NewClient(defaultTailnet, nil)
 	c.UserAgent = "tailscale-k8s-operator"
 	c.HTTPClient = credentials.Client(ctx)
-	tsc := &tsClientImpl{
-		Client:  c,
-		baseURL: defaultBaseURL,
-		tailnet: defaultTailnet,
-	}
-	return tsc, nil
+	return c, nil
 }
 
 type tsClient interface {
 	CreateKey(ctx context.Context, caps tailscale.KeyCapabilities) (string, *tailscale.Key, error)
 	Device(ctx context.Context, deviceID string, fields *tailscale.DeviceFieldsOpts) (*tailscale.Device, error)
 	DeleteDevice(ctx context.Context, nodeStableID string) error
-	getVIPService(ctx context.Context, name tailcfg.ServiceName) (*VIPService, error)
-	createOrUpdateVIPService(ctx context.Context, svc *VIPService) error
-	deleteVIPService(ctx context.Context, name tailcfg.ServiceName) error
-}
-
-type tsClientImpl struct {
-	*tailscale.Client
-	baseURL string
-	tailnet string
-}
-
-// VIPService is a Tailscale VIPService with Tailscale API JSON representation.
-type VIPService struct {
-	// Name is a VIPService name in form svc:<leftmost-label-of-service-DNS-name>.
-	Name tailcfg.ServiceName `json:"name,omitempty"`
-	// Addrs are the IP addresses of the VIP Service. There are two addresses:
-	// the first is IPv4 and the second is IPv6.
-	// When creating a new VIP Service, the IP addresses are optional: if no
-	// addresses are specified then they will be selected. If an IPv4 address is
-	// specified at index 0, then that address will attempt to be used. An IPv6
-	// address can not be specified upon creation.
-	Addrs []string `json:"addrs,omitempty"`
-	// Comment is an optional text string for display in the admin panel.
-	Comment string `json:"comment,omitempty"`
-	// Ports are the ports of a VIPService that will be configured via Tailscale serve config.
-	// If set, any node wishing to advertise this VIPService must have this port configured via Tailscale serve.
-	Ports []string `json:"ports,omitempty"`
-	// Tags are optional ACL tags that will be applied to the VIPService.
-	Tags []string `json:"tags,omitempty"`
-}
-
-// GetVIPServiceByName retrieves a VIPService by its name. It returns 404 if the VIPService is not found.
-func (c *tsClientImpl) getVIPService(ctx context.Context, name tailcfg.ServiceName) (*VIPService, error) {
-	path := fmt.Sprintf("%s/api/v2/tailnet/%s/vip-services/%s", c.baseURL, c.tailnet, url.PathEscape(name.String()))
-	req, err := http.NewRequestWithContext(ctx, httpm.GET, path, nil)
-	if err != nil {
-		return nil, fmt.Errorf("error creating new HTTP request: %w", err)
-	}
-	b, resp, err := c.sendRequest(req)
-	if err != nil {
-		return nil, fmt.Errorf("error making Tailsale API request: %w", err)
-	}
-	// If status code was not successful, return the error.
-	// TODO: Change the check for the StatusCode to include other 2XX success codes.
-	if resp.StatusCode != http.StatusOK {
-		return nil, handleErrorResponse(b, resp)
-	}
-	svc := &VIPService{}
-	if err := json.Unmarshal(b, svc); err != nil {
-		return nil, err
-	}
-	return svc, nil
-}
-
-// createOrUpdateVIPService creates or updates a VIPService by its name. Caller must ensure that, if the
-// VIPService already exists, the VIPService is fetched first to ensure that any auto-allocated IP addresses are not
-// lost during the update. If the VIPService was created without any IP addresses explicitly set (so that they were
-// auto-allocated by Tailscale) any subsequent request to this function that does not set any IP addresses will error.
-func (c *tsClientImpl) createOrUpdateVIPService(ctx context.Context, svc *VIPService) error {
-	data, err := json.Marshal(svc)
-	if err != nil {
-		return err
-	}
-	path := fmt.Sprintf("%s/api/v2/tailnet/%s/vip-services/%s", c.baseURL, c.tailnet, url.PathEscape(svc.Name.String()))
-	req, err := http.NewRequestWithContext(ctx, httpm.PUT, path, bytes.NewBuffer(data))
-	if err != nil {
-		return fmt.Errorf("error creating new HTTP request: %w", err)
-	}
-	b, resp, err := c.sendRequest(req)
-	if err != nil {
-		return fmt.Errorf("error making Tailscale API request: %w", err)
-	}
-	// If status code was not successful, return the error.
-	// TODO: Change the check for the StatusCode to include other 2XX success codes.
-	if resp.StatusCode != http.StatusOK {
-		return handleErrorResponse(b, resp)
-	}
-	return nil
-}
-
-// DeleteVIPServiceByName deletes a VIPService by its name. It returns an error if the VIPService
-// does not exist or if the deletion fails.
-func (c *tsClientImpl) deleteVIPService(ctx context.Context, name tailcfg.ServiceName) error {
-	path := fmt.Sprintf("%s/api/v2/tailnet/%s/vip-services/%s", c.baseURL, c.tailnet, url.PathEscape(name.String()))
-	req, err := http.NewRequestWithContext(ctx, httpm.DELETE, path, nil)
-	if err != nil {
-		return fmt.Errorf("error creating new HTTP request: %w", err)
-	}
-	b, resp, err := c.sendRequest(req)
-	if err != nil {
-		return fmt.Errorf("error making Tailscale API request: %w", err)
-	}
-	// If status code was not successful, return the error.
-	if resp.StatusCode != http.StatusOK {
-		return handleErrorResponse(b, resp)
-	}
-	return nil
-}
-
-// sendRequest add the authentication key to the request and sends it. It
-// receives the response and reads up to 10MB of it.
-func (c *tsClientImpl) sendRequest(req *http.Request) ([]byte, *http.Response, error) {
-	resp, err := c.Do(req)
-	if err != nil {
-		return nil, resp, fmt.Errorf("error actually doing request: %w", err)
-	}
-	defer resp.Body.Close()
-
-	// Read response
-	b, err := io.ReadAll(resp.Body)
-	if err != nil {
-		err = fmt.Errorf("error reading response body: %v", err)
-	}
-	return b, resp, err
-}
-
-// handleErrorResponse decodes the error message from the server and returns
-// an ErrResponse from it.
-func handleErrorResponse(b []byte, resp *http.Response) error {
-	var errResp tailscale.ErrResponse
-	if err := json.Unmarshal(b, &errResp); err != nil {
-		return err
-	}
-	errResp.Status = resp.StatusCode
-	return errResp
+	GetVIPService(ctx context.Context, name tailcfg.ServiceName) (*tailscale.VIPService, error)
+	CreateOrUpdateVIPService(ctx context.Context, svc *tailscale.VIPService) error
+	DeleteVIPService(ctx context.Context, name tailcfg.ServiceName) error
 }

cmd/stund/depaware.txt

@@ -88,13 +88,11 @@ tailscale.com/cmd/stund dependencies: (generated by github.com/tailscale/depawar
         golang.org/x/crypto/cryptobyte                               from crypto/ecdsa+
         golang.org/x/crypto/cryptobyte/asn1                          from crypto/ecdsa+
         golang.org/x/crypto/curve25519                               from golang.org/x/crypto/nacl/box+
-        golang.org/x/crypto/hkdf                                     from crypto/tls+
         golang.org/x/crypto/internal/alias                           from golang.org/x/crypto/chacha20+
         golang.org/x/crypto/internal/poly1305                        from golang.org/x/crypto/chacha20poly1305+
         golang.org/x/crypto/nacl/box                                 from tailscale.com/types/key
         golang.org/x/crypto/nacl/secretbox                           from golang.org/x/crypto/nacl/box
         golang.org/x/crypto/salsa20/salsa                            from golang.org/x/crypto/nacl/box+
-        golang.org/x/crypto/sha3                                     from crypto/internal/mlkem768+
         golang.org/x/net/dns/dnsmessage                              from net+
         golang.org/x/net/http/httpguts                               from net/http
         golang.org/x/net/http/httpproxy                              from net/http
@@ -116,7 +114,7 @@ tailscale.com/cmd/stund dependencies: (generated by github.com/tailscale/depawar
         container/list                                               from crypto/tls+
         context                                                      from crypto/tls+
         crypto                                                       from crypto/ecdh+
-        crypto/aes                                                   from crypto/ecdsa+
+        crypto/aes                                                   from crypto/internal/hpke+
         crypto/cipher                                                from crypto/aes+
         crypto/des                                                   from crypto/tls+
         crypto/dsa                                                   from crypto/x509
@@ -124,32 +122,59 @@ tailscale.com/cmd/stund dependencies: (generated by github.com/tailscale/depawar
         crypto/ecdsa                                                 from crypto/tls+
         crypto/ed25519                                               from crypto/tls+
         crypto/elliptic                                              from crypto/ecdsa+
-        crypto/hmac                                                  from crypto/tls+
-        crypto/internal/alias                                        from crypto/aes+
-        crypto/internal/bigmod                                       from crypto/ecdsa+
+        crypto/hmac                                                  from crypto/tls
         crypto/internal/boring                                       from crypto/aes+
         crypto/internal/boring/bbig                                  from crypto/ecdsa+
         crypto/internal/boring/sig                                   from crypto/internal/boring
-        crypto/internal/edwards25519                                 from crypto/ed25519
-        crypto/internal/edwards25519/field                           from crypto/ecdh+
+        crypto/internal/entropy                                      from crypto/internal/fips140/drbg
+        crypto/internal/fips140                                      from crypto/internal/fips140/aes+
+        crypto/internal/fips140/aes                                  from crypto/aes+
+        crypto/internal/fips140/aes/gcm                              from crypto/cipher+
+        crypto/internal/fips140/alias                                from crypto/cipher+
+        crypto/internal/fips140/bigmod                               from crypto/internal/fips140/ecdsa+
+        crypto/internal/fips140/check                                from crypto/internal/fips140/aes+
+        crypto/internal/fips140/drbg                                 from crypto/internal/fips140/aes/gcm+
+        crypto/internal/fips140/ecdh                                 from crypto/ecdh
+        crypto/internal/fips140/ecdsa                                from crypto/ecdsa
+        crypto/internal/fips140/ed25519                              from crypto/ed25519
+        crypto/internal/fips140/edwards25519                         from crypto/internal/fips140/ed25519
+        crypto/internal/fips140/edwards25519/field                   from crypto/ecdh+
+        crypto/internal/fips140/hkdf                                 from crypto/internal/fips140/tls13+
+        crypto/internal/fips140/hmac                                 from crypto/hmac+
+        crypto/internal/fips140/mlkem                                from crypto/tls
+        crypto/internal/fips140/nistec                               from crypto/elliptic+
+        crypto/internal/fips140/nistec/fiat                          from crypto/internal/fips140/nistec
+        crypto/internal/fips140/rsa                                  from crypto/rsa
+        crypto/internal/fips140/sha256                               from crypto/internal/fips140/check+
+        crypto/internal/fips140/sha3                                 from crypto/internal/fips140/hmac+
+        crypto/internal/fips140/sha512                               from crypto/internal/fips140/ecdsa+
+        crypto/internal/fips140/subtle                               from crypto/internal/fips140/aes+
+        crypto/internal/fips140/tls12                                from crypto/tls
+        crypto/internal/fips140/tls13                                from crypto/tls
+        crypto/internal/fips140deps/byteorder                        from crypto/internal/fips140/aes+
+        crypto/internal/fips140deps/cpu                              from crypto/internal/fips140/aes+
+        crypto/internal/fips140deps/godebug                          from crypto/internal/fips140+
+        crypto/internal/fips140hash                                  from crypto/ecdsa+
+        crypto/internal/fips140only                                  from crypto/cipher+
         crypto/internal/hpke                                         from crypto/tls
-        crypto/internal/mlkem768                                     from crypto/tls
-        crypto/internal/nistec                                       from crypto/ecdh+
-        crypto/internal/nistec/fiat                                  from crypto/internal/nistec
+        crypto/internal/impl                                         from crypto/internal/fips140/aes+
         crypto/internal/randutil                                     from crypto/dsa+
+        crypto/internal/sysrand                                      from crypto/internal/entropy+
         crypto/md5                                                   from crypto/tls+
         crypto/rand                                                  from crypto/ed25519+
         crypto/rc4                                                   from crypto/tls
         crypto/rsa                                                   from crypto/tls+
         crypto/sha1                                                  from crypto/tls+
         crypto/sha256                                                from crypto/tls+
+        crypto/sha3                                                  from crypto/internal/fips140hash
         crypto/sha512                                                from crypto/ecdsa+
-        crypto/subtle                                                from crypto/aes+
+        crypto/subtle                                                from crypto/cipher+
         crypto/tls                                                   from net/http+
+        crypto/tls/internal/fips140tls                               from crypto/tls
         crypto/x509                                                  from crypto/tls
    D    crypto/x509/internal/macos                                   from crypto/x509
         crypto/x509/pkix                                             from crypto/x509
-        embed                                                        from crypto/internal/nistec+
+        embed                                                        from google.golang.org/protobuf/internal/editiondefaults+
         encoding                                                     from encoding/json+
         encoding/asn1                                                from crypto/x509+
         encoding/base32                                              from github.com/go-json-experiment/json
@@ -169,23 +194,22 @@ tailscale.com/cmd/stund dependencies: (generated by github.com/tailscale/depawar
         hash/maphash                                                 from go4.org/mem
         html                                                         from net/http/pprof+
         internal/abi                                                 from crypto/x509/internal/macos+
-        internal/asan                                                from syscall
+        internal/asan                                                from syscall+
         internal/bisect                                              from internal/godebug
         internal/bytealg                                             from bytes+
-        internal/byteorder                                           from crypto/aes+
+        internal/byteorder                                           from crypto/cipher+
         internal/chacha8rand                                         from math/rand/v2+
-        internal/concurrent                                          from unique
         internal/coverage/rtcov                                      from runtime
-        internal/cpu                                                 from crypto/aes+
+        internal/cpu                                                 from crypto/internal/fips140deps/cpu+
         internal/filepathlite                                        from os+
         internal/fmtsort                                             from fmt
-        internal/goarch                                              from crypto/aes+
+        internal/goarch                                              from crypto/internal/fips140deps/cpu+
         internal/godebug                                             from crypto/tls+
         internal/godebugs                                            from internal/godebug+
-        internal/goexperiment                                        from runtime
+        internal/goexperiment                                        from runtime+
         internal/goos                                                from crypto/x509+
         internal/itoa                                                from internal/poll+
-        internal/msan                                                from syscall
+        internal/msan                                                from syscall+
         internal/nettrace                                            from net+
         internal/oserror                                             from io/fs+
         internal/poll                                                from net+
@@ -195,17 +219,20 @@ tailscale.com/cmd/stund dependencies: (generated by github.com/tailscale/depawar
         internal/reflectlite                                         from context+
         internal/runtime/atomic                                      from internal/runtime/exithook+
         internal/runtime/exithook                                    from runtime
+        internal/runtime/maps                                        from reflect+
+        internal/runtime/math                                        from internal/runtime/maps+
+        internal/runtime/sys                                         from crypto/subtle+
    L    internal/runtime/syscall                                     from runtime+
         internal/singleflight                                        from net
         internal/stringslite                                         from embed+
+        internal/sync                                                from sync+
         internal/syscall/execenv                                     from os
-  LD    internal/syscall/unix                                        from crypto/rand+
-   W    internal/syscall/windows                                     from crypto/rand+
+  LD    internal/syscall/unix                                        from crypto/internal/sysrand+
+   W    internal/syscall/windows                                     from crypto/internal/sysrand+
    W    internal/syscall/windows/registry                            from mime+
    W    internal/syscall/windows/sysdll                              from internal/syscall/windows+
         internal/testlog                                             from os
         internal/unsafeheader                                        from internal/reflectlite+
-        internal/weak                                                from unique
         io                                                           from bufio+
         io/fs                                                        from crypto/x509+
         iter                                                         from maps+
@@ -216,7 +243,7 @@ tailscale.com/cmd/stund dependencies: (generated by github.com/tailscale/depawar
         math/big                                                     from crypto/dsa+
         math/bits                                                    from compress/flate+
         math/rand                                                    from math/big+
-        math/rand/v2                                                 from internal/concurrent+
+        math/rand/v2                                                 from crypto/ecdsa+
         mime                                                         from github.com/prometheus/common/expfmt+
         mime/multipart                                               from net/http
         mime/quotedprintable                                         from mime/multipart
@@ -229,17 +256,15 @@ tailscale.com/cmd/stund dependencies: (generated by github.com/tailscale/depawar
         net/netip                                                    from go4.org/netipx+
         net/textproto                                                from golang.org/x/net/http/httpguts+
         net/url                                                      from crypto/x509+
-        os                                                           from crypto/rand+
+        os                                                           from crypto/internal/sysrand+
         os/signal                                                    from tailscale.com/cmd/stund
         path                                                         from github.com/prometheus/client_golang/prometheus/internal+
         path/filepath                                                from crypto/x509+
         reflect                                                      from crypto/x509+
         regexp                                                       from github.com/prometheus/client_golang/prometheus/internal+
         regexp/syntax                                                from regexp
-        runtime                                                      from crypto/internal/nistec+
+        runtime                                                      from crypto/internal/fips140+
         runtime/debug                                                from github.com/prometheus/client_golang/prometheus+
-        runtime/internal/math                                        from runtime
-        runtime/internal/sys                                         from runtime
         runtime/metrics                                              from github.com/prometheus/client_golang/prometheus+
         runtime/pprof                                                from net/http/pprof
         runtime/trace                                                from net/http/pprof
@@ -249,7 +274,7 @@ tailscale.com/cmd/stund dependencies: (generated by github.com/tailscale/depawar
         strings                                                      from bufio+
         sync                                                         from compress/flate+
         sync/atomic                                                  from context+
-        syscall                                                      from crypto/rand+
+        syscall                                                      from crypto/internal/sysrand+
         text/tabwriter                                               from runtime/pprof
         time                                                         from compress/gzip+
         unicode                                                      from bytes+
@@ -257,3 +282,4 @@ tailscale.com/cmd/stund dependencies: (generated by github.com/tailscale/depawar
         unicode/utf8                                                 from bufio+
         unique                                                       from net/netip
         unsafe                                                       from bytes+
+        weak                                                         from unique

cmd/tailscale/cli/file.go

@@ -28,6 +28,7 @@ import (
 	"tailscale.com/client/tailscale/apitype"
 	"tailscale.com/cmd/tailscale/cli/ffcomplete"
 	"tailscale.com/envknob"
+	"tailscale.com/ipn/ipnstate"
 	"tailscale.com/net/tsaddr"
 	"tailscale.com/syncs"
 	"tailscale.com/tailcfg"
@@ -268,46 +269,77 @@ func getTargetStableID(ctx context.Context, ipStr string) (id tailcfg.StableNode
 	if err != nil {
 		return "", false, err
 	}
-	fts, err := localClient.FileTargets(ctx)
-	if err != nil {
-		return "", false, err
-	}
-	for _, ft := range fts {
-		n := ft.Node
-		for _, a := range n.Addresses {
-			if a.Addr() != ip {
-				continue
-			}
-			isOffline = n.Online != nil && !*n.Online
-			return n.StableID, isOffline, nil
-		}
-	}
-	return "", false, fileTargetErrorDetail(ctx, ip)
-}
 
-// fileTargetErrorDetail returns a non-nil error saying why ip is an
-// invalid file sharing target.
-func fileTargetErrorDetail(ctx context.Context, ip netip.Addr) error {
-	found := false
-	if st, err := localClient.Status(ctx); err == nil && st.Self != nil {
-		for _, peer := range st.Peer {
-			for _, pip := range peer.TailscaleIPs {
-				if pip == ip {
-					found = true
-					if peer.UserID != st.Self.UserID {
-						return errors.New("owned by different user; can only send files to your own devices")
-					}
-				}
+	st, err := localClient.Status(ctx)
+	if err != nil {
+		// This likely means tailscaled is unreachable or returned an error on /localapi/v0/status.
+		return "", false, fmt.Errorf("failed to get local status: %w", err)
+	}
+	if st == nil {
+		// Handle the case if the daemon returns nil with no error.
+		return "", false, errors.New("no status available")
+	}
+	if st.Self == nil {
+		// We have a status structure, but it doesn’t include Self info. Probably not connected.
+		return "", false, errors.New("local node is not configured or missing Self information")
+	}
+
+	// Find the PeerStatus that corresponds to ip.
+	var foundPeer *ipnstate.PeerStatus
+peerLoop:
+	for _, ps := range st.Peer {
+		for _, pip := range ps.TailscaleIPs {
+			if pip == ip {
+				foundPeer = ps
+				break peerLoop
 			}
 		}
 	}
-	if found {
-		return errors.New("target seems to be running an old Tailscale version")
+
+	// If we didn’t find a matching peer at all:
+	if foundPeer == nil {
+		if !tsaddr.IsTailscaleIP(ip) {
+			return "", false, fmt.Errorf("unknown target; %v is not a Tailscale IP address", ip)
+		}
+		return "", false, errors.New("unknown target; not in your Tailnet")
 	}
-	if !tsaddr.IsTailscaleIP(ip) {
-		return fmt.Errorf("unknown target; %v is not a Tailscale IP address", ip)
+
+	// We found a peer. Decide whether we can send files to it:
+	isOffline = !foundPeer.Online
+
+	switch foundPeer.TaildropTarget {
+	case ipnstate.TaildropTargetAvailable:
+		return foundPeer.ID, isOffline, nil
+
+	case ipnstate.TaildropTargetNoNetmapAvailable:
+		return "", isOffline, errors.New("cannot send files: no netmap available on this node")
+
+	case ipnstate.TaildropTargetIpnStateNotRunning:
+		return "", isOffline, errors.New("cannot send files: local Tailscale is not connected to the tailnet")
+
+	case ipnstate.TaildropTargetMissingCap:
+		return "", isOffline, errors.New("cannot send files: missing required Taildrop capability")
+
+	case ipnstate.TaildropTargetOffline:
+		return "", isOffline, errors.New("cannot send files: peer is offline")
+
+	case ipnstate.TaildropTargetNoPeerInfo:
+		return "", isOffline, errors.New("cannot send files: invalid or unrecognized peer")
+
+	case ipnstate.TaildropTargetUnsupportedOS:
+		return "", isOffline, errors.New("cannot send files: target's OS does not support Taildrop")
+
+	case ipnstate.TaildropTargetNoPeerAPI:
+		return "", isOffline, errors.New("cannot send files: target is not advertising a file sharing API")
+
+	case ipnstate.TaildropTargetOwnedByOtherUser:
+		return "", isOffline, errors.New("cannot send files: peer is owned by a different user")
+
+	case ipnstate.TaildropTargetUnknown:
+		fallthrough
+	default:
+		return "", isOffline, fmt.Errorf("cannot send files: unknown or indeterminate reason")
 	}
-	return errors.New("unknown target; not in your Tailnet")
 }
 
 const maxSniff = 4 << 20

cmd/tailscale/cli/up.go

@@ -27,8 +27,8 @@ import (
 	"github.com/peterbourgon/ff/v3/ffcli"
 	qrcode "github.com/skip2/go-qrcode"
 	"golang.org/x/oauth2/clientcredentials"
-	"tailscale.com/client/tailscale"
 	"tailscale.com/health/healthmsg"
+	"tailscale.com/internal/client/tailscale"
 	"tailscale.com/ipn"
 	"tailscale.com/ipn/ipnstate"
 	"tailscale.com/net/netutil"
@@ -1097,12 +1097,6 @@ func exitNodeIP(p *ipn.Prefs, st *ipnstate.Status) (ip netip.Addr) {
 	return
 }
 
-func init() {
-	// Required to use our client API. We're fine with the instability since the
-	// client lives in the same repo as this code.
-	tailscale.I_Acknowledge_This_API_Is_Unstable = true
-}
-
 // resolveAuthKey either returns v unchanged (in the common case) or, if it
 // starts with "tskey-client-" (as Tailscale OAuth secrets do) parses it like
 //

cmd/tailscale/depaware.txt

@@ -93,6 +93,7 @@ tailscale.com/cmd/tailscale dependencies: (generated by github.com/tailscale/dep
         tailscale.com/health                                         from tailscale.com/net/tlsdial+
         tailscale.com/health/healthmsg                               from tailscale.com/cmd/tailscale/cli
         tailscale.com/hostinfo                                       from tailscale.com/client/web+
+        tailscale.com/internal/client/tailscale                      from tailscale.com/cmd/tailscale/cli
         tailscale.com/internal/noiseconn                             from tailscale.com/cmd/tailscale/cli
         tailscale.com/ipn                                            from tailscale.com/client/local+
         tailscale.com/ipn/ipnstate                                   from tailscale.com/client/local+
@@ -194,14 +195,13 @@ tailscale.com/cmd/tailscale dependencies: (generated by github.com/tailscale/dep
         golang.org/x/crypto/cryptobyte                               from crypto/ecdsa+
         golang.org/x/crypto/cryptobyte/asn1                          from crypto/ecdsa+
         golang.org/x/crypto/curve25519                               from golang.org/x/crypto/nacl/box+
-        golang.org/x/crypto/hkdf                                     from crypto/tls+
+        golang.org/x/crypto/hkdf                                     from tailscale.com/control/controlbase
         golang.org/x/crypto/internal/alias                           from golang.org/x/crypto/chacha20+
         golang.org/x/crypto/internal/poly1305                        from golang.org/x/crypto/chacha20poly1305+
         golang.org/x/crypto/nacl/box                                 from tailscale.com/types/key
         golang.org/x/crypto/nacl/secretbox                           from golang.org/x/crypto/nacl/box
         golang.org/x/crypto/pbkdf2                                   from software.sslmate.com/src/go-pkcs12
         golang.org/x/crypto/salsa20/salsa                            from golang.org/x/crypto/nacl/box+
-        golang.org/x/crypto/sha3                                     from crypto/internal/mlkem768+
    W    golang.org/x/exp/constraints                                 from github.com/dblohm7/wingoes/pe+
         golang.org/x/exp/maps                                        from tailscale.com/util/syspolicy/internal/metrics+
         golang.org/x/net/bpf                                         from github.com/mdlayher/netlink+
@@ -245,7 +245,7 @@ tailscale.com/cmd/tailscale dependencies: (generated by github.com/tailscale/dep
         container/list                                               from crypto/tls+
         context                                                      from crypto/tls+
         crypto                                                       from crypto/ecdh+
-        crypto/aes                                                   from crypto/ecdsa+
+        crypto/aes                                                   from crypto/internal/hpke+
         crypto/cipher                                                from crypto/aes+
         crypto/des                                                   from crypto/tls+
         crypto/dsa                                                   from crypto/x509
@@ -254,34 +254,61 @@ tailscale.com/cmd/tailscale dependencies: (generated by github.com/tailscale/dep
         crypto/ed25519                                               from crypto/tls+
         crypto/elliptic                                              from crypto/ecdsa+
         crypto/hmac                                                  from crypto/tls+
-        crypto/internal/alias                                        from crypto/aes+
-        crypto/internal/bigmod                                       from crypto/ecdsa+
         crypto/internal/boring                                       from crypto/aes+
         crypto/internal/boring/bbig                                  from crypto/ecdsa+
         crypto/internal/boring/sig                                   from crypto/internal/boring
-        crypto/internal/edwards25519                                 from crypto/ed25519
-        crypto/internal/edwards25519/field                           from crypto/ecdh+
+        crypto/internal/entropy                                      from crypto/internal/fips140/drbg
+        crypto/internal/fips140                                      from crypto/internal/fips140/aes+
+        crypto/internal/fips140/aes                                  from crypto/aes+
+        crypto/internal/fips140/aes/gcm                              from crypto/cipher+
+        crypto/internal/fips140/alias                                from crypto/cipher+
+        crypto/internal/fips140/bigmod                               from crypto/internal/fips140/ecdsa+
+        crypto/internal/fips140/check                                from crypto/internal/fips140/aes+
+        crypto/internal/fips140/drbg                                 from crypto/internal/fips140/aes/gcm+
+        crypto/internal/fips140/ecdh                                 from crypto/ecdh
+        crypto/internal/fips140/ecdsa                                from crypto/ecdsa
+        crypto/internal/fips140/ed25519                              from crypto/ed25519
+        crypto/internal/fips140/edwards25519                         from crypto/internal/fips140/ed25519
+        crypto/internal/fips140/edwards25519/field                   from crypto/ecdh+
+        crypto/internal/fips140/hkdf                                 from crypto/internal/fips140/tls13+
+        crypto/internal/fips140/hmac                                 from crypto/hmac+
+        crypto/internal/fips140/mlkem                                from crypto/tls
+        crypto/internal/fips140/nistec                               from crypto/elliptic+
+        crypto/internal/fips140/nistec/fiat                          from crypto/internal/fips140/nistec
+        crypto/internal/fips140/rsa                                  from crypto/rsa
+        crypto/internal/fips140/sha256                               from crypto/internal/fips140/check+
+        crypto/internal/fips140/sha3                                 from crypto/internal/fips140/hmac+
+        crypto/internal/fips140/sha512                               from crypto/internal/fips140/ecdsa+
+        crypto/internal/fips140/subtle                               from crypto/internal/fips140/aes+
+        crypto/internal/fips140/tls12                                from crypto/tls
+        crypto/internal/fips140/tls13                                from crypto/tls
+        crypto/internal/fips140deps/byteorder                        from crypto/internal/fips140/aes+
+        crypto/internal/fips140deps/cpu                              from crypto/internal/fips140/aes+
+        crypto/internal/fips140deps/godebug                          from crypto/internal/fips140+
+        crypto/internal/fips140hash                                  from crypto/ecdsa+
+        crypto/internal/fips140only                                  from crypto/cipher+
         crypto/internal/hpke                                         from crypto/tls
-        crypto/internal/mlkem768                                     from crypto/tls
-        crypto/internal/nistec                                       from crypto/ecdh+
-        crypto/internal/nistec/fiat                                  from crypto/internal/nistec
+        crypto/internal/impl                                         from crypto/internal/fips140/aes+
         crypto/internal/randutil                                     from crypto/dsa+
+        crypto/internal/sysrand                                      from crypto/internal/entropy+
         crypto/md5                                                   from crypto/tls+
         crypto/rand                                                  from crypto/ed25519+
         crypto/rc4                                                   from crypto/tls
         crypto/rsa                                                   from crypto/tls+
         crypto/sha1                                                  from crypto/tls+
         crypto/sha256                                                from crypto/tls+
+        crypto/sha3                                                  from crypto/internal/fips140hash
         crypto/sha512                                                from crypto/ecdsa+
-        crypto/subtle                                                from crypto/aes+
+        crypto/subtle                                                from crypto/cipher+
         crypto/tls                                                   from github.com/miekg/dns+
+        crypto/tls/internal/fips140tls                               from crypto/tls
         crypto/x509                                                  from crypto/tls+
    D    crypto/x509/internal/macos                                   from crypto/x509
         crypto/x509/pkix                                             from crypto/x509+
   DW    database/sql/driver                                          from github.com/google/uuid
    W    debug/dwarf                                                  from debug/pe
    W    debug/pe                                                     from github.com/dblohm7/wingoes/pe
-        embed                                                        from crypto/internal/nistec+
+        embed                                                        from github.com/peterbourgon/ff/v3+
         encoding                                                     from encoding/gob+
         encoding/asn1                                                from crypto/x509+
         encoding/base32                                              from github.com/fxamacker/cbor/v2+
@@ -306,23 +333,22 @@ tailscale.com/cmd/tailscale dependencies: (generated by github.com/tailscale/dep
         image/color                                                  from github.com/skip2/go-qrcode+
         image/png                                                    from github.com/skip2/go-qrcode
         internal/abi                                                 from crypto/x509/internal/macos+
-        internal/asan                                                from syscall
+        internal/asan                                                from syscall+
         internal/bisect                                              from internal/godebug
         internal/bytealg                                             from bytes+
-        internal/byteorder                                           from crypto/aes+
+        internal/byteorder                                           from crypto/cipher+
         internal/chacha8rand                                         from math/rand/v2+
-        internal/concurrent                                          from unique
         internal/coverage/rtcov                                      from runtime
-        internal/cpu                                                 from crypto/aes+
+        internal/cpu                                                 from crypto/internal/fips140deps/cpu+
         internal/filepathlite                                        from os+
         internal/fmtsort                                             from fmt+
-        internal/goarch                                              from crypto/aes+
+        internal/goarch                                              from crypto/internal/fips140deps/cpu+
         internal/godebug                                             from archive/tar+
         internal/godebugs                                            from internal/godebug+
-        internal/goexperiment                                        from runtime
+        internal/goexperiment                                        from runtime+
         internal/goos                                                from crypto/x509+
         internal/itoa                                                from internal/poll+
-        internal/msan                                                from syscall
+        internal/msan                                                from syscall+
         internal/nettrace                                            from net+
         internal/oserror                                             from io/fs+
         internal/poll                                                from net+
@@ -331,18 +357,21 @@ tailscale.com/cmd/tailscale dependencies: (generated by github.com/tailscale/dep
         internal/reflectlite                                         from context+
         internal/runtime/atomic                                      from internal/runtime/exithook+
         internal/runtime/exithook                                    from runtime
+        internal/runtime/maps                                        from reflect+
+        internal/runtime/math                                        from internal/runtime/maps+
+        internal/runtime/sys                                         from crypto/subtle+
    L    internal/runtime/syscall                                     from runtime+
         internal/saferio                                             from debug/pe+
         internal/singleflight                                        from net
         internal/stringslite                                         from embed+
+        internal/sync                                                from sync+
         internal/syscall/execenv                                     from os+
-  LD    internal/syscall/unix                                        from crypto/rand+
-   W    internal/syscall/windows                                     from crypto/rand+
+  LD    internal/syscall/unix                                        from crypto/internal/sysrand+
+   W    internal/syscall/windows                                     from crypto/internal/sysrand+
    W    internal/syscall/windows/registry                            from mime+
    W    internal/syscall/windows/sysdll                              from internal/syscall/windows+
         internal/testlog                                             from os
         internal/unsafeheader                                        from internal/reflectlite+
-        internal/weak                                                from unique
         io                                                           from archive/tar+
         io/fs                                                        from archive/tar+
         io/ioutil                                                    from github.com/mitchellh/go-ps+
@@ -368,7 +397,7 @@ tailscale.com/cmd/tailscale dependencies: (generated by github.com/tailscale/dep
         net/netip                                                    from go4.org/netipx+
         net/textproto                                                from golang.org/x/net/http/httpguts+
         net/url                                                      from crypto/x509+
-        os                                                           from crypto/rand+
+        os                                                           from crypto/internal/sysrand+
         os/exec                                                      from github.com/coreos/go-iptables/iptables+
         os/signal                                                    from tailscale.com/cmd/tailscale/cli
         os/user                                                      from archive/tar+
@@ -379,8 +408,6 @@ tailscale.com/cmd/tailscale dependencies: (generated by github.com/tailscale/dep
         regexp/syntax                                                from regexp
         runtime                                                      from archive/tar+
         runtime/debug                                                from tailscale.com+
-        runtime/internal/math                                        from runtime
-        runtime/internal/sys                                         from runtime
         slices                                                       from tailscale.com/client/web+
         sort                                                         from compress/flate+
         strconv                                                      from archive/tar+
@@ -397,3 +424,4 @@ tailscale.com/cmd/tailscale dependencies: (generated by github.com/tailscale/dep
         unicode/utf8                                                 from bufio+
         unique                                                       from net/netip
         unsafe                                                       from bytes+
+        weak                                                         from unique

cmd/tailscaled/depaware.txt

@@ -81,7 +81,6 @@ tailscale.com/cmd/tailscaled dependencies: (generated by github.com/tailscale/de
    L    github.com/aws/smithy-go/transport/http                      from github.com/aws/aws-sdk-go-v2/aws/middleware+
    L    github.com/aws/smithy-go/transport/http/internal/io          from github.com/aws/smithy-go/transport/http
    L    github.com/aws/smithy-go/waiter                              from github.com/aws/aws-sdk-go-v2/service/ssm
-        github.com/bits-and-blooms/bitset                            from github.com/gaissmai/bart
    L    github.com/coreos/go-iptables/iptables                       from tailscale.com/util/linuxfw
   LD 💣 github.com/creack/pty                                        from tailscale.com/ssh/tailssh
    W 💣 github.com/dblohm7/wingoes                                   from github.com/dblohm7/wingoes/com+
@@ -93,6 +92,8 @@ tailscale.com/cmd/tailscaled dependencies: (generated by github.com/tailscale/de
      💣 github.com/djherbis/times                                    from tailscale.com/drive/driveimpl
         github.com/fxamacker/cbor/v2                                 from tailscale.com/tka
         github.com/gaissmai/bart                                     from tailscale.com/net/tstun+
+        github.com/gaissmai/bart/internal/bitset                     from github.com/gaissmai/bart+
+        github.com/gaissmai/bart/internal/sparse                     from github.com/gaissmai/bart
         github.com/go-json-experiment/json                           from tailscale.com/types/opt+
         github.com/go-json-experiment/json/internal                  from github.com/go-json-experiment/json/internal/jsonflags+
         github.com/go-json-experiment/json/internal/jsonflags        from github.com/go-json-experiment/json/internal/jsonopts+
@@ -271,6 +272,7 @@ tailscale.com/cmd/tailscaled dependencies: (generated by github.com/tailscale/de
         tailscale.com/internal/noiseconn                             from tailscale.com/control/controlclient
         tailscale.com/ipn                                            from tailscale.com/client/local+
         tailscale.com/ipn/conffile                                   from tailscale.com/cmd/tailscaled+
+     💣 tailscale.com/ipn/desktop                                    from tailscale.com/cmd/tailscaled+
      💣 tailscale.com/ipn/ipnauth                                    from tailscale.com/ipn/ipnlocal+
         tailscale.com/ipn/ipnlocal                                   from tailscale.com/cmd/tailscaled+
         tailscale.com/ipn/ipnserver                                  from tailscale.com/cmd/tailscaled
@@ -447,14 +449,13 @@ tailscale.com/cmd/tailscaled dependencies: (generated by github.com/tailscale/de
         golang.org/x/crypto/cryptobyte                               from crypto/ecdsa+
         golang.org/x/crypto/cryptobyte/asn1                          from crypto/ecdsa+
         golang.org/x/crypto/curve25519                               from golang.org/x/crypto/ssh+
-        golang.org/x/crypto/hkdf                                     from crypto/tls+
+        golang.org/x/crypto/hkdf                                     from tailscale.com/control/controlbase
         golang.org/x/crypto/internal/alias                           from golang.org/x/crypto/chacha20+
         golang.org/x/crypto/internal/poly1305                        from golang.org/x/crypto/chacha20poly1305+
         golang.org/x/crypto/nacl/box                                 from tailscale.com/types/key
         golang.org/x/crypto/nacl/secretbox                           from golang.org/x/crypto/nacl/box
         golang.org/x/crypto/poly1305                                 from github.com/tailscale/wireguard-go/device
         golang.org/x/crypto/salsa20/salsa                            from golang.org/x/crypto/nacl/box+
-        golang.org/x/crypto/sha3                                     from crypto/internal/mlkem768+
   LD    golang.org/x/crypto/ssh                                      from github.com/pkg/sftp+
   LD    golang.org/x/crypto/ssh/internal/bcrypt_pbkdf                from golang.org/x/crypto/ssh
         golang.org/x/exp/constraints                                 from github.com/dblohm7/wingoes/pe+
@@ -502,7 +503,7 @@ tailscale.com/cmd/tailscaled dependencies: (generated by github.com/tailscale/de
         container/list                                               from crypto/tls+
         context                                                      from crypto/tls+
         crypto                                                       from crypto/ecdh+
-        crypto/aes                                                   from crypto/ecdsa+
+        crypto/aes                                                   from crypto/internal/hpke+
         crypto/cipher                                                from crypto/aes+
         crypto/des                                                   from crypto/tls+
         crypto/dsa                                                   from crypto/x509+
@@ -511,34 +512,61 @@ tailscale.com/cmd/tailscaled dependencies: (generated by github.com/tailscale/de
         crypto/ed25519                                               from crypto/tls+
         crypto/elliptic                                              from crypto/ecdsa+
         crypto/hmac                                                  from crypto/tls+
-        crypto/internal/alias                                        from crypto/aes+
-        crypto/internal/bigmod                                       from crypto/ecdsa+
         crypto/internal/boring                                       from crypto/aes+
         crypto/internal/boring/bbig                                  from crypto/ecdsa+
         crypto/internal/boring/sig                                   from crypto/internal/boring
-        crypto/internal/edwards25519                                 from crypto/ed25519
-        crypto/internal/edwards25519/field                           from crypto/ecdh+
+        crypto/internal/entropy                                      from crypto/internal/fips140/drbg
+        crypto/internal/fips140                                      from crypto/internal/fips140/aes+
+        crypto/internal/fips140/aes                                  from crypto/aes+
+        crypto/internal/fips140/aes/gcm                              from crypto/cipher+
+        crypto/internal/fips140/alias                                from crypto/cipher+
+        crypto/internal/fips140/bigmod                               from crypto/internal/fips140/ecdsa+
+        crypto/internal/fips140/check                                from crypto/internal/fips140/aes+
+        crypto/internal/fips140/drbg                                 from crypto/internal/fips140/aes/gcm+
+        crypto/internal/fips140/ecdh                                 from crypto/ecdh
+        crypto/internal/fips140/ecdsa                                from crypto/ecdsa
+        crypto/internal/fips140/ed25519                              from crypto/ed25519
+        crypto/internal/fips140/edwards25519                         from crypto/internal/fips140/ed25519
+        crypto/internal/fips140/edwards25519/field                   from crypto/ecdh+
+        crypto/internal/fips140/hkdf                                 from crypto/internal/fips140/tls13+
+        crypto/internal/fips140/hmac                                 from crypto/hmac+
+        crypto/internal/fips140/mlkem                                from crypto/tls
+        crypto/internal/fips140/nistec                               from crypto/elliptic+
+        crypto/internal/fips140/nistec/fiat                          from crypto/internal/fips140/nistec
+        crypto/internal/fips140/rsa                                  from crypto/rsa
+        crypto/internal/fips140/sha256                               from crypto/internal/fips140/check+
+        crypto/internal/fips140/sha3                                 from crypto/internal/fips140/hmac+
+        crypto/internal/fips140/sha512                               from crypto/internal/fips140/ecdsa+
+        crypto/internal/fips140/subtle                               from crypto/internal/fips140/aes+
+        crypto/internal/fips140/tls12                                from crypto/tls
+        crypto/internal/fips140/tls13                                from crypto/tls
+        crypto/internal/fips140deps/byteorder                        from crypto/internal/fips140/aes+
+        crypto/internal/fips140deps/cpu                              from crypto/internal/fips140/aes+
+        crypto/internal/fips140deps/godebug                          from crypto/internal/fips140+
+        crypto/internal/fips140hash                                  from crypto/ecdsa+
+        crypto/internal/fips140only                                  from crypto/cipher+
         crypto/internal/hpke                                         from crypto/tls
-        crypto/internal/mlkem768                                     from crypto/tls
-        crypto/internal/nistec                                       from crypto/ecdh+
-        crypto/internal/nistec/fiat                                  from crypto/internal/nistec
+        crypto/internal/impl                                         from crypto/internal/fips140/aes+
         crypto/internal/randutil                                     from crypto/dsa+
+        crypto/internal/sysrand                                      from crypto/internal/entropy+
         crypto/md5                                                   from crypto/tls+
         crypto/rand                                                  from crypto/ed25519+
         crypto/rc4                                                   from crypto/tls+
         crypto/rsa                                                   from crypto/tls+
         crypto/sha1                                                  from crypto/tls+
         crypto/sha256                                                from crypto/tls+
+        crypto/sha3                                                  from crypto/internal/fips140hash
         crypto/sha512                                                from crypto/ecdsa+
-        crypto/subtle                                                from crypto/aes+
+        crypto/subtle                                                from crypto/cipher+
         crypto/tls                                                   from github.com/aws/aws-sdk-go-v2/aws/transport/http+
+        crypto/tls/internal/fips140tls                               from crypto/tls
         crypto/x509                                                  from crypto/tls+
    D    crypto/x509/internal/macos                                   from crypto/x509
         crypto/x509/pkix                                             from crypto/x509+
   DW    database/sql/driver                                          from github.com/google/uuid
    W    debug/dwarf                                                  from debug/pe
    W    debug/pe                                                     from github.com/dblohm7/wingoes/pe
-        embed                                                        from crypto/internal/nistec+
+        embed                                                        from github.com/tailscale/web-client-prebuilt+
         encoding                                                     from encoding/gob+
         encoding/asn1                                                from crypto/x509+
         encoding/base32                                              from github.com/fxamacker/cbor/v2+
@@ -560,23 +588,22 @@ tailscale.com/cmd/tailscaled dependencies: (generated by github.com/tailscale/de
         html                                                         from html/template+
         html/template                                                from github.com/gorilla/csrf
         internal/abi                                                 from crypto/x509/internal/macos+
-        internal/asan                                                from syscall
+        internal/asan                                                from syscall+
         internal/bisect                                              from internal/godebug
         internal/bytealg                                             from bytes+
-        internal/byteorder                                           from crypto/aes+
+        internal/byteorder                                           from crypto/cipher+
         internal/chacha8rand                                         from math/rand/v2+
-        internal/concurrent                                          from unique
         internal/coverage/rtcov                                      from runtime
-        internal/cpu                                                 from crypto/aes+
+        internal/cpu                                                 from crypto/internal/fips140deps/cpu+
         internal/filepathlite                                        from os+
         internal/fmtsort                                             from fmt+
-        internal/goarch                                              from crypto/aes+
+        internal/goarch                                              from crypto/internal/fips140deps/cpu+
         internal/godebug                                             from archive/tar+
         internal/godebugs                                            from internal/godebug+
-        internal/goexperiment                                        from runtime
+        internal/goexperiment                                        from runtime+
         internal/goos                                                from crypto/x509+
         internal/itoa                                                from internal/poll+
-        internal/msan                                                from syscall
+        internal/msan                                                from syscall+
         internal/nettrace                                            from net+
         internal/oserror                                             from io/fs+
         internal/poll                                                from net+
@@ -586,18 +613,21 @@ tailscale.com/cmd/tailscaled dependencies: (generated by github.com/tailscale/de
         internal/reflectlite                                         from context+
         internal/runtime/atomic                                      from internal/runtime/exithook+
         internal/runtime/exithook                                    from runtime
+        internal/runtime/maps                                        from reflect+
+        internal/runtime/math                                        from internal/runtime/maps+
+        internal/runtime/sys                                         from crypto/subtle+
    L    internal/runtime/syscall                                     from runtime+
         internal/saferio                                             from debug/pe+
         internal/singleflight                                        from net
         internal/stringslite                                         from embed+
+        internal/sync                                                from sync+
         internal/syscall/execenv                                     from os+
-  LD    internal/syscall/unix                                        from crypto/rand+
-   W    internal/syscall/windows                                     from crypto/rand+
+  LD    internal/syscall/unix                                        from crypto/internal/sysrand+
+   W    internal/syscall/windows                                     from crypto/internal/sysrand+
    W    internal/syscall/windows/registry                            from mime+
    W    internal/syscall/windows/sysdll                              from internal/syscall/windows+
         internal/testlog                                             from os
         internal/unsafeheader                                        from internal/reflectlite+
-        internal/weak                                                from unique
         io                                                           from archive/tar+
         io/fs                                                        from archive/tar+
         io/ioutil                                                    from github.com/aws/aws-sdk-go-v2/aws/protocol/query+
@@ -624,7 +654,7 @@ tailscale.com/cmd/tailscaled dependencies: (generated by github.com/tailscale/de
         net/netip                                                    from github.com/tailscale/wireguard-go/conn+
         net/textproto                                                from github.com/aws/aws-sdk-go-v2/aws/signer/v4+
         net/url                                                      from crypto/x509+
-        os                                                           from crypto/rand+
+        os                                                           from crypto/internal/sysrand+
         os/exec                                                      from github.com/aws/aws-sdk-go-v2/credentials/processcreds+
         os/signal                                                    from tailscale.com/cmd/tailscaled
         os/user                                                      from archive/tar+
@@ -635,8 +665,6 @@ tailscale.com/cmd/tailscaled dependencies: (generated by github.com/tailscale/de
         regexp/syntax                                                from regexp
         runtime                                                      from archive/tar+
         runtime/debug                                                from github.com/aws/aws-sdk-go-v2/internal/sync/singleflight+
-        runtime/internal/math                                        from runtime
-        runtime/internal/sys                                         from runtime
         runtime/pprof                                                from net/http/pprof+
         runtime/trace                                                from net/http/pprof
         slices                                                       from tailscale.com/appc+
@@ -655,3 +683,4 @@ tailscale.com/cmd/tailscaled dependencies: (generated by github.com/tailscale/de
         unicode/utf8                                                 from bufio+
         unique                                                       from net/netip
         unsafe                                                       from bytes+
+        weak                                                         from unique

cmd/tailscaled/tailscaled_windows.go

@@ -44,6 +44,7 @@ import (
 	"golang.zx2c4.com/wireguard/windows/tunnel/winipcfg"
 	"tailscale.com/drive/driveimpl"
 	"tailscale.com/envknob"
+	"tailscale.com/ipn/desktop"
 	"tailscale.com/logpolicy"
 	"tailscale.com/logtail/backoff"
 	"tailscale.com/net/dns"
@@ -335,6 +336,13 @@ func beWindowsSubprocess() bool {
 
 	sys.Set(driveimpl.NewFileSystemForRemote(log.Printf))
 
+	if sessionManager, err := desktop.NewSessionManager(log.Printf); err == nil {
+		sys.Set(sessionManager)
+	} else {
+		// Errors creating the session manager are unexpected, but not fatal.
+		log.Printf("[unexpected]: error creating a desktop session manager: %v", err)
+	}
+
 	publicLogID, _ := logid.ParsePublicID(logID)
 	err = startIPNServer(ctx, log.Printf, publicLogID, sys)
 	if err != nil {

cmd/testwrapper/flakytest/flakytest.go

@@ -9,8 +9,12 @@ package flakytest
 import (
 	"fmt"
 	"os"
+	"path"
 	"regexp"
+	"sync"
 	"testing"
+
+	"tailscale.com/util/mak"
 )
 
 // FlakyTestLogMessage is a sentinel value that is printed to stderr when a
@@ -25,6 +29,11 @@ const FlakeAttemptEnv = "TS_TESTWRAPPER_ATTEMPT"
 
 var issueRegexp = regexp.MustCompile(`\Ahttps://github\.com/tailscale/[a-zA-Z0-9_.-]+/issues/\d+\z`)
 
+var (
+	rootFlakesMu sync.Mutex
+	rootFlakes   map[string]bool
+)
+
 // Mark sets the current test as a flaky test, such that if it fails, it will
 // be retried a few times on failure. issue must be a GitHub issue that tracks
 // the status of the flaky test being marked, of the format:
@@ -41,4 +50,24 @@ func Mark(t testing.TB, issue string) {
 		fmt.Fprintf(os.Stderr, "%s: %s\n", FlakyTestLogMessage, issue)
 	}
 	t.Logf("flakytest: issue tracking this flaky test: %s", issue)
+
+	// Record the root test name as flakey.
+	rootFlakesMu.Lock()
+	defer rootFlakesMu.Unlock()
+	mak.Set(&rootFlakes, t.Name(), true)
+}
+
+// Marked reports whether the current test or one of its parents was marked flaky.
+func Marked(t testing.TB) bool {
+	n := t.Name()
+	for {
+		if rootFlakes[n] {
+			return true
+		}
+		n = path.Dir(n)
+		if n == "." || n == "/" {
+			break
+		}
+	}
+	return false
 }

cmd/testwrapper/flakytest/flakytest_test.go

@@ -41,3 +41,49 @@ func TestFlakeRun(t *testing.T) {
 		t.Fatal("First run in testwrapper, failing so that test is retried. This is expected.")
 	}
 }
+
+func TestMarked_Root(t *testing.T) {
+	Mark(t, "https://github.com/tailscale/tailscale/issues/0")
+
+	t.Run("child", func(t *testing.T) {
+		t.Run("grandchild", func(t *testing.T) {
+			if got, want := Marked(t), true; got != want {
+				t.Fatalf("Marked(t) = %t, want %t", got, want)
+			}
+		})
+
+		if got, want := Marked(t), true; got != want {
+			t.Fatalf("Marked(t) = %t, want %t", got, want)
+		}
+	})
+
+	if got, want := Marked(t), true; got != want {
+		t.Fatalf("Marked(t) = %t, want %t", got, want)
+	}
+}
+
+func TestMarked_Subtest(t *testing.T) {
+	t.Run("flaky", func(t *testing.T) {
+		Mark(t, "https://github.com/tailscale/tailscale/issues/0")
+
+		t.Run("child", func(t *testing.T) {
+			t.Run("grandchild", func(t *testing.T) {
+				if got, want := Marked(t), true; got != want {
+					t.Fatalf("Marked(t) = %t, want %t", got, want)
+				}
+			})
+
+			if got, want := Marked(t), true; got != want {
+				t.Fatalf("Marked(t) = %t, want %t", got, want)
+			}
+		})
+
+		if got, want := Marked(t), true; got != want {
+			t.Fatalf("Marked(t) = %t, want %t", got, want)
+		}
+	})
+
+	if got, want := Marked(t), false; got != want {
+		t.Fatalf("Marked(t) = %t, want %t", got, want)
+	}
+}

cmd/testwrapper/testwrapper.go

@@ -10,6 +10,7 @@ package main
 import (
 	"bufio"
 	"bytes"
+	"cmp"
 	"context"
 	"encoding/json"
 	"errors"
@@ -22,13 +23,7 @@ import (
 	"sort"
 	"strings"
 	"time"
-	"unicode"
 
-	"github.com/dave/courtney/scanner"
-	"github.com/dave/courtney/shared"
-	"github.com/dave/courtney/tester"
-	"github.com/dave/patsy"
-	"github.com/dave/patsy/vos"
 	"tailscale.com/cmd/testwrapper/flakytest"
 	"tailscale.com/util/slicesx"
 )
@@ -65,11 +60,12 @@ type packageTests struct {
 }
 
 type goTestOutput struct {
-	Time    time.Time
-	Action  string
-	Package string
-	Test    string
-	Output  string
+	Time       time.Time
+	Action     string
+	ImportPath string
+	Package    string
+	Test       string
+	Output     string
 }
 
 var debug = os.Getenv("TS_TESTWRAPPER_DEBUG") != ""
@@ -117,42 +113,43 @@ func runTests(ctx context.Context, attempt int, pt *packageTests, goTestArgs, te
 	for s.Scan() {
 		var goOutput goTestOutput
 		if err := json.Unmarshal(s.Bytes(), &goOutput); err != nil {
-			if errors.Is(err, io.EOF) || errors.Is(err, os.ErrClosed) {
-				break
-			}
-
-			// `go test -json` outputs invalid JSON when a build fails.
-			// In that case, discard the the output and start reading again.
-			// The build error will be printed to stderr.
-			// See: https://github.com/golang/go/issues/35169
-			if _, ok := err.(*json.SyntaxError); ok {
-				fmt.Println(s.Text())
-				continue
-			}
-			panic(err)
+			return fmt.Errorf("failed to parse go test output %q: %w", s.Bytes(), err)
 		}
-		pkg := goOutput.Package
+		pkg := cmp.Or(
+			goOutput.Package,
+			"build:"+goOutput.ImportPath, // can be "./cmd" while Package is "tailscale.com/cmd" so use separate namespace
+		)
 		pkgTests := resultMap[pkg]
 		if pkgTests == nil {
-			pkgTests = make(map[string]*testAttempt)
+			pkgTests = map[string]*testAttempt{
+				"": {}, // Used for start time and build logs.
+			}
 			resultMap[pkg] = pkgTests
 		}
 		if goOutput.Test == "" {
 			switch goOutput.Action {
 			case "start":
-				pkgTests[""] = &testAttempt{start: goOutput.Time}
-			case "fail", "pass", "skip":
+				pkgTests[""].start = goOutput.Time
+			case "build-output":
+				pkgTests[""].logs.WriteString(goOutput.Output)
+			case "build-fail", "fail", "pass", "skip":
 				for _, test := range pkgTests {
 					if test.testName != "" && test.outcome == "" {
 						test.outcome = "fail"
 						ch <- test
 					}
 				}
+				outcome := goOutput.Action
+				if outcome == "build-fail" {
+					outcome = "FAIL"
+				}
+				pkgTests[""].logs.WriteString(goOutput.Output)
 				ch <- &testAttempt{
 					pkg:         goOutput.Package,
-					outcome:     goOutput.Action,
+					outcome:     outcome,
 					start:       pkgTests[""].start,
 					end:         goOutput.Time,
+					logs:        pkgTests[""].logs,
 					pkgFinished: true,
 				}
 			}
@@ -221,6 +218,9 @@ func main() {
 	}
 	toRun := []*nextRun{firstRun}
 	printPkgOutcome := func(pkg, outcome string, attempt int, runtime time.Duration) {
+		if pkg == "" {
+			return // We reach this path on a build error.
+		}
 		if outcome == "skip" {
 			fmt.Printf("?\t%s [skipped/no tests] \n", pkg)
 			return
@@ -238,30 +238,6 @@ func main() {
 		fmt.Printf("%s\t%s\t%.3fs\n", outcome, pkg, runtime.Seconds())
 	}
 
-	// Check for -coverprofile argument and filter it out
-	combinedCoverageFilename := ""
-	filteredGoTestArgs := make([]string, 0, len(goTestArgs))
-	preceededByCoverProfile := false
-	for _, arg := range goTestArgs {
-		if arg == "-coverprofile" {
-			preceededByCoverProfile = true
-		} else if preceededByCoverProfile {
-			combinedCoverageFilename = strings.TrimSpace(arg)
-			preceededByCoverProfile = false
-		} else {
-			filteredGoTestArgs = append(filteredGoTestArgs, arg)
-		}
-	}
-	goTestArgs = filteredGoTestArgs
-
-	runningWithCoverage := combinedCoverageFilename != ""
-	if runningWithCoverage {
-		fmt.Printf("Will log coverage to %v\n", combinedCoverageFilename)
-	}
-
-	// Keep track of all test coverage files. With each retry, we'll end up
-	// with additional coverage files that will be combined when we finish.
-	coverageFiles := make([]string, 0)
 	for len(toRun) > 0 {
 		var thisRun *nextRun
 		thisRun, toRun = toRun[0], toRun[1:]
@@ -275,27 +251,13 @@ func main() {
 			fmt.Printf("\n\nAttempt #%d: Retrying flaky tests:\n\nflakytest failures JSON: %s\n\n", thisRun.attempt, j)
 		}
 
-		goTestArgsWithCoverage := testArgs
-		if runningWithCoverage {
-			coverageFile := fmt.Sprintf("/tmp/coverage_%d.out", thisRun.attempt)
-			coverageFiles = append(coverageFiles, coverageFile)
-			goTestArgsWithCoverage = make([]string, len(goTestArgs), len(goTestArgs)+2)
-			copy(goTestArgsWithCoverage, goTestArgs)
-			goTestArgsWithCoverage = append(
-				goTestArgsWithCoverage,
-				fmt.Sprintf("-coverprofile=%v", coverageFile),
-				"-covermode=set",
-				"-coverpkg=./...",
-			)
-		}
-
 		toRetry := make(map[string][]*testAttempt) // pkg -> tests to retry
 		for _, pt := range thisRun.tests {
 			ch := make(chan *testAttempt)
 			runErr := make(chan error, 1)
 			go func() {
 				defer close(runErr)
-				runErr <- runTests(ctx, thisRun.attempt, pt, goTestArgsWithCoverage, testArgs, ch)
+				runErr <- runTests(ctx, thisRun.attempt, pt, goTestArgs, testArgs, ch)
 			}()
 
 			var failed bool
@@ -314,6 +276,7 @@ func main() {
 						// when a package times out.
 						failed = true
 					}
+					os.Stdout.ReadFrom(&tr.logs)
 					printPkgOutcome(tr.pkg, tr.outcome, thisRun.attempt, tr.end.Sub(tr.start))
 					continue
 				}
@@ -372,107 +335,4 @@ func main() {
 		}
 		toRun = append(toRun, nextRun)
 	}
-
-	if runningWithCoverage {
-		intermediateCoverageFilename := "/tmp/coverage.out_intermediate"
-		if err := combineCoverageFiles(intermediateCoverageFilename, coverageFiles); err != nil {
-			fmt.Printf("error combining coverage files: %v\n", err)
-			os.Exit(2)
-		}
-
-		if err := processCoverageWithCourtney(intermediateCoverageFilename, combinedCoverageFilename, testArgs); err != nil {
-			fmt.Printf("error processing coverage with courtney: %v\n", err)
-			os.Exit(3)
-		}
-
-		fmt.Printf("Wrote combined coverage to %v\n", combinedCoverageFilename)
-	}
-}
-
-func combineCoverageFiles(intermediateCoverageFilename string, coverageFiles []string) error {
-	combinedCoverageFile, err := os.OpenFile(intermediateCoverageFilename, os.O_CREATE|os.O_WRONLY|os.O_TRUNC, 0644)
-	if err != nil {
-		return fmt.Errorf("create /tmp/coverage.out: %w", err)
-	}
-	defer combinedCoverageFile.Close()
-	w := bufio.NewWriter(combinedCoverageFile)
-	defer w.Flush()
-
-	for fileNumber, coverageFile := range coverageFiles {
-		f, err := os.Open(coverageFile)
-		if err != nil {
-			return fmt.Errorf("open %v: %w", coverageFile, err)
-		}
-		defer f.Close()
-		in := bufio.NewReader(f)
-		line := 0
-		for {
-			r, _, err := in.ReadRune()
-			if err != nil {
-				if err != io.EOF {
-					return fmt.Errorf("read %v: %w", coverageFile, err)
-				}
-				break
-			}
-
-			// On all but the first coverage file, skip the coverage file header
-			if fileNumber > 0 && line == 0 {
-				continue
-			}
-			if r == '\n' {
-				line++
-			}
-
-			// filter for only printable characters because coverage file sometimes includes junk on 2nd line
-			if unicode.IsPrint(r) || r == '\n' {
-				if _, err := w.WriteRune(r); err != nil {
-					return fmt.Errorf("write %v: %w", combinedCoverageFile.Name(), err)
-				}
-			}
-		}
-	}
-
-	return nil
-}
-
-// processCoverageWithCourtney post-processes code coverage to exclude less
-// meaningful sections like 'if err != nil { return err}', as well as
-// anything marked with a '// notest' comment.
-//
-// instead of running the courtney as a separate program, this embeds
-// courtney for easier integration.
-func processCoverageWithCourtney(intermediateCoverageFilename, combinedCoverageFilename string, testArgs []string) error {
-	env := vos.Os()
-
-	setup := &shared.Setup{
-		Env:      vos.Os(),
-		Paths:    patsy.NewCache(env),
-		TestArgs: testArgs,
-		Load:     intermediateCoverageFilename,
-		Output:   combinedCoverageFilename,
-	}
-	if err := setup.Parse(testArgs); err != nil {
-		return fmt.Errorf("parse args: %w", err)
-	}
-
-	s := scanner.New(setup)
-	if err := s.LoadProgram(); err != nil {
-		return fmt.Errorf("load program: %w", err)
-	}
-	if err := s.ScanPackages(); err != nil {
-		return fmt.Errorf("scan packages: %w", err)
-	}
-
-	t := tester.New(setup)
-	if err := t.Load(); err != nil {
-		return fmt.Errorf("load: %w", err)
-	}
-	if err := t.ProcessExcludes(s.Excludes); err != nil {
-		return fmt.Errorf("process excludes: %w", err)
-	}
-	if err := t.Save(); err != nil {
-		return fmt.Errorf("save: %w", err)
-	}
-
-	return nil
 }

cmd/testwrapper/testwrapper_test.go

@@ -11,6 +11,7 @@ import (
 	"os/exec"
 	"path/filepath"
 	"regexp"
+	"strings"
 	"sync"
 	"testing"
 )
@@ -154,24 +155,24 @@ func TestBuildError(t *testing.T) {
 		t.Fatalf("writing package: %s", err)
 	}
 
-	buildErr := []byte("builderror_test.go:3:1: expected declaration, found derp\nFAIL	command-line-arguments [setup failed]")
+	wantErr := "builderror_test.go:3:1: expected declaration, found derp\nFAIL"
 
 	// Confirm `go test` exits with code 1.
 	goOut, err := exec.Command("go", "test", testfile).CombinedOutput()
 	if code, ok := errExitCode(err); !ok || code != 1 {
-		t.Fatalf("go test %s: expected error with exit code 0 but got: %v", testfile, err)
+		t.Fatalf("go test %s: got exit code %d, want 1 (err: %v)", testfile, code, err)
 	}
-	if !bytes.Contains(goOut, buildErr) {
-		t.Fatalf("go test %s: expected build error containing %q but got:\n%s", testfile, buildErr, goOut)
+	if !strings.Contains(string(goOut), wantErr) {
+		t.Fatalf("go test %s: got output %q, want output containing %q", testfile, goOut, wantErr)
 	}
 
 	// Confirm `testwrapper` exits with code 1.
 	twOut, err := cmdTestwrapper(t, testfile).CombinedOutput()
 	if code, ok := errExitCode(err); !ok || code != 1 {
-		t.Fatalf("testwrapper %s: expected error with exit code 0 but got: %v", testfile, err)
+		t.Fatalf("testwrapper %s: got exit code %d, want 1 (err: %v)", testfile, code, err)
 	}
-	if !bytes.Contains(twOut, buildErr) {
-		t.Fatalf("testwrapper %s: expected build error containing %q but got:\n%s", testfile, buildErr, twOut)
+	if !strings.Contains(string(twOut), wantErr) {
+		t.Fatalf("testwrapper %s: got output %q, want output containing %q", testfile, twOut, wantErr)
 	}
 
 	if testing.Verbose() {

cmd/tsconnect/common.go

@@ -176,6 +176,10 @@ func runEsbuild(buildOptions esbuild.BuildOptions) esbuild.BuildResult {
 // wasm_exec.js runtime helper library from the Go toolchain.
 func setupEsbuildWasmExecJS(build esbuild.PluginBuild) {
 	wasmExecSrcPath := filepath.Join(runtime.GOROOT(), "misc", "wasm", "wasm_exec.js")
+	if _, err := os.Stat(wasmExecSrcPath); os.IsNotExist(err) {
+		// Go 1.24+ location:
+		wasmExecSrcPath = filepath.Join(runtime.GOROOT(), "lib", "wasm", "wasm_exec.js")
+	}
 	build.OnResolve(esbuild.OnResolveOptions{
 		Filter: "./wasm_exec$",
 	}, func(args esbuild.OnResolveArgs) (esbuild.OnResolveResult, error) {

control/controlclient/map.go

@@ -89,7 +89,6 @@ type mapSession struct {
 	lastPopBrowserURL      string
 	lastTKAInfo            *tailcfg.TKAInfo
 	lastNetmapSummary      string // from NetworkMap.VeryConcise
-	lastMaxExpiry          time.Duration
 }
 
 // newMapSession returns a mostly unconfigured new mapSession.
@@ -384,9 +383,6 @@ func (ms *mapSession) updateStateFromResponse(resp *tailcfg.MapResponse) {
 	if resp.TKAInfo != nil {
 		ms.lastTKAInfo = resp.TKAInfo
 	}
-	if resp.MaxKeyDuration > 0 {
-		ms.lastMaxExpiry = resp.MaxKeyDuration
-	}
 }
 
 var (
@@ -819,7 +815,6 @@ func (ms *mapSession) netmap() *netmap.NetworkMap {
 		DERPMap:           ms.lastDERPMap,
 		ControlHealth:     ms.lastHealth,
 		TKAEnabled:        ms.lastTKAInfo != nil && !ms.lastTKAInfo.Disabled,
-		MaxKeyDuration:    ms.lastMaxExpiry,
 	}
 
 	if ms.lastTKAInfo != nil && ms.lastTKAInfo.Head != "" {

derp/derp_server.go

@@ -137,6 +137,7 @@ type Server struct {
 	metaCert    []byte // the encoded x509 cert to send after LetsEncrypt cert+intermediate
 	dupPolicy   dupPolicy
 	debug       bool
+	localClient local.Client
 
 	// Counters:
 	packetsSent, bytesSent     expvar.Int
@@ -485,6 +486,16 @@ func (s *Server) SetVerifyClientURLFailOpen(v bool) {
 	s.verifyClientsURLFailOpen = v
 }
 
+// SetTailscaledSocketPath sets the unix socket path to use to talk to
+// tailscaled if client verification is enabled.
+//
+// If unset or set to the empty string, the default path for the operating
+// system is used.
+func (s *Server) SetTailscaledSocketPath(path string) {
+	s.localClient.Socket = path
+	s.localClient.UseSocketOnly = path != ""
+}
+
 // SetTCPWriteTimeout sets the timeout for writing to connected clients.
 // This timeout does not apply to mesh connections.
 // Defaults to 2 seconds.
@@ -1320,8 +1331,6 @@ func (c *sclient) requestMeshUpdate() {
 	}
 }
 
-var localClient local.Client
-
 // isMeshPeer reports whether the client is a trusted mesh peer
 // node in the DERP region.
 func (s *Server) isMeshPeer(info *clientInfo) bool {
@@ -1340,7 +1349,7 @@ func (s *Server) verifyClient(ctx context.Context, clientKey key.NodePublic, inf
 
 	// tailscaled-based verification:
 	if s.verifyClientsLocalTailscaled {
-		_, err := localClient.WhoIsNodeKey(ctx, clientKey)
+		_, err := s.localClient.WhoIsNodeKey(ctx, clientKey)
 		if err == tailscale.ErrPeerNotFound {
 			return fmt.Errorf("peer %v not authorized (not found in local tailscaled)", clientKey)
 		}
@@ -2240,7 +2249,7 @@ func (s *Server) ConsistencyCheck() error {
 func (s *Server) checkVerifyClientsLocalTailscaled() error {
 	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
 	defer cancel()
-	status, err := localClient.StatusWithoutPeers(ctx)
+	status, err := s.localClient.StatusWithoutPeers(ctx)
 	if err != nil {
 		return fmt.Errorf("localClient.Status: %w", err)
 	}

docs/windows/policy/en-US/tailscale.adml

@@ -109,6 +109,14 @@ If you enable this policy setting, users will not be allowed to disconnect Tails
 If necessary, it can be used along with Unattended Mode to keep Tailscale connected regardless of whether a user is logged in. This can be used to facilitate remote access to a device or ensure connectivity to a Domain Controller before a user logs in.
 
 If you disable or don't configure this policy setting, users will be allowed to disconnect Tailscale at their will.]]></string>
+            <string id="ReconnectAfter">Configure automatic reconnect delay</string>
+            <string id="ReconnectAfter_Help"><![CDATA[This policy setting controls when Tailscale will attempt to reconnect automatically after a user disconnects it. It helps users remain connected most of the time and retain access to corporate resources without preventing them from temporarily disconnecting Tailscale. To configure whether and when Tailscale can be disconnected, see the "Restrict users from disconnecting Tailscale (always-on mode)" policy setting.
+
+If you enable this policy setting, you can specify how long Tailscale will wait before attempting to reconnect after a user disconnects. The value should be specified as a Go duration: for example, 30s, 5m, or 1h30m. If the value is left blank, or if the specified duration is zero, Tailscale will not attempt to reconnect automatically.
+
+If you disable or don't configure this policy setting, Tailscale will only reconnect if a user chooses to or if required by a different policy setting.
+
+Refer to https://pkg.go.dev/time#ParseDuration for information about the supported duration strings.]]></string>
             <string id="ExitNodeAllowLANAccess">Allow Local Network Access when an Exit Node is in use</string>
             <string id="ExitNodeAllowLANAccess_Help"><![CDATA[This policy can be used to require that the Allow Local Network Access setting is configured a certain way.
 
@@ -280,6 +288,12 @@ See https://tailscale.com/kb/1315/mdm-keys#set-your-organization-name for more d
                 <text>The options below allow configuring exceptions where disconnecting Tailscale is permitted.</text>
                 <dropdownList refId="AlwaysOn_OverrideWithReason" noSort="true" defaultItem="0">Disconnects with reason:</dropdownList>
             </presentation>
+            <presentation id="ReconnectAfter">
+                <text>The delay must be a valid Go duration string, such as 30s, 5m, or 1h30m, all without spaces or any other symbols.</text>
+                <textBox refId="ReconnectAfterDelay">
+                    <label>Reconnect after:</label>
+                </textBox>
+            </presentation>
             <presentation id="ExitNodeID">
                 <textBox refId="ExitNodeIDPrompt">
                     <label>Exit Node:</label>

docs/windows/policy/tailscale.admx

@@ -156,6 +156,13 @@
         </enum>
       </elements>
     </policy>
+    <policy name="ReconnectAfter" class="Machine" displayName="$(string.ReconnectAfter)" explainText="$(string.ReconnectAfter_Help)" presentation="$(presentation.ReconnectAfter)" key="Software\Policies\Tailscale">
+      <parentCategory ref="Settings_Category" />
+      <supportedOn ref="SINCE_V1_82" />
+      <elements>
+        <text id="ReconnectAfterDelay" valueName="ReconnectAfter" required="true" />
+      </elements>
+    </policy>
     <policy name="ExitNodeAllowLANAccess" class="Machine" displayName="$(string.ExitNodeAllowLANAccess)" explainText="$(string.ExitNodeAllowLANAccess_Help)" key="Software\Policies\Tailscale" valueName="ExitNodeAllowLANAccess">
       <parentCategory ref="Settings_Category" />
       <supportedOn ref="PARTIAL_FULL_SINCE_V1_56" />

go.mod

@@ -1,6 +1,6 @@
 module tailscale.com
 
-go 1.23.1
+go 1.24.0
 
 require (
 	filippo.io/mkcert v1.4.4
@@ -21,8 +21,6 @@ require (
 	github.com/coreos/go-iptables v0.7.1-0.20240112124308-65c67c9f46e6
 	github.com/coreos/go-systemd v0.0.0-20191104093116-d3cd4ed1dbcf
 	github.com/creack/pty v1.1.23
-	github.com/dave/courtney v0.4.0
-	github.com/dave/patsy v0.0.0-20210517141501-957256f50cba
 	github.com/dblohm7/wingoes v0.0.0-20240119213807-a09d6be7affa
 	github.com/digitalocean/go-smbios v0.0.0-20180907143718-390a4f403a8e
 	github.com/distribution/reference v0.6.0
@@ -33,8 +31,8 @@ require (
 	github.com/fogleman/gg v1.3.0
 	github.com/frankban/quicktest v1.14.6
 	github.com/fxamacker/cbor/v2 v2.7.0
-	github.com/gaissmai/bart v0.11.1
-	github.com/go-json-experiment/json v0.0.0-20250103232110-6a9a0fde9288
+	github.com/gaissmai/bart v0.18.0
+	github.com/go-json-experiment/json v0.0.0-20250223041408-d3c622f1b874
 	github.com/go-logr/zapr v1.3.0
 	github.com/go-ole/go-ole v1.3.0
 	github.com/godbus/dbus/v5 v5.1.1-0.20230522191255-76236955d466
@@ -76,7 +74,7 @@ require (
 	github.com/tailscale/certstore v0.1.1-0.20231202035212-d3fa0460f47e
 	github.com/tailscale/depaware v0.0.0-20250112153213-b748de04d81b
 	github.com/tailscale/goexpect v0.0.0-20210902213824-6e8c725cea41
-	github.com/tailscale/golang-x-crypto v0.0.0-20240604161659-3fde5e568aa4
+	github.com/tailscale/golang-x-crypto v0.0.0-20250218230618-9a281fd8faca
 	github.com/tailscale/goupnp v1.0.1-0.20210804011211-c64d0f06ea05
 	github.com/tailscale/hujson v0.0.0-20221223112325-20486734a56a
 	github.com/tailscale/mkctr v0.0.0-20250110151924-54977352e4a6
@@ -95,7 +93,7 @@ require (
 	go.uber.org/zap v1.27.0
 	go4.org/mem v0.0.0-20240501181205-ae6ca9944745
 	go4.org/netipx v0.0.0-20231129151722-fdeea329fbba
-	golang.org/x/crypto v0.33.0
+	golang.org/x/crypto v0.35.0
 	golang.org/x/exp v0.0.0-20250210185358-939b2ce775ac
 	golang.org/x/mod v0.23.0
 	golang.org/x/net v0.35.0
@@ -129,15 +127,12 @@ require (
 	github.com/OpenPeeDeeP/depguard/v2 v2.2.0 // indirect
 	github.com/alecthomas/go-check-sumtype v0.1.4 // indirect
 	github.com/alexkohler/nakedret/v2 v2.0.4 // indirect
-	github.com/bits-and-blooms/bitset v1.13.0 // indirect
 	github.com/bombsimon/wsl/v4 v4.2.1 // indirect
 	github.com/butuzov/mirror v1.1.0 // indirect
 	github.com/catenacyber/perfsprint v0.7.1 // indirect
 	github.com/ccojocar/zxcvbn-go v1.0.2 // indirect
 	github.com/ckaznocha/intrange v0.1.0 // indirect
 	github.com/cyphar/filepath-securejoin v0.3.6 // indirect
-	github.com/dave/astrid v0.0.0-20170323122508-8c2895878b14 // indirect
-	github.com/dave/brenda v1.1.0 // indirect
 	github.com/docker/go-connections v0.5.0 // indirect
 	github.com/docker/go-units v0.5.0 // indirect
 	github.com/felixge/httpsnoop v1.0.4 // indirect

go.sum

@@ -167,8 +167,6 @@ github.com/beorn7/perks v0.0.0-20180321164747-3a771d992973/go.mod h1:Dwedo/Wpr24
 github.com/beorn7/perks v1.0.0/go.mod h1:KWe93zE9D1o94FZ5RNwFwVgaQK1VOXiVxmqh+CedLV8=
 github.com/beorn7/perks v1.0.1 h1:VlbKKnNfV8bJzeqoa4cOKqO6bYr3WgKZxO8Z16+hsOM=
 github.com/beorn7/perks v1.0.1/go.mod h1:G2ZrVWU2WbWT9wwq4/hrbKbnv/1ERSJQ0ibhJ6rlkpw=
-github.com/bits-and-blooms/bitset v1.13.0 h1:bAQ9OPNFYbGHV6Nez0tmNI0RiEu7/hxlYJRUA0wFAVE=
-github.com/bits-and-blooms/bitset v1.13.0/go.mod h1:7hO7Gc7Pp1vODcmWvKMRA9BNmbv6a/7QIWpPxHddWR8=
 github.com/bkielbasa/cyclop v1.2.1 h1:AeF71HZDob1P2/pRm1so9cd1alZnrpyc4q2uP2l0gJY=
 github.com/bkielbasa/cyclop v1.2.1/go.mod h1:K/dT/M0FPAiYjBgQGau7tz+3TMh4FWAEqlMhzFWCrgM=
 github.com/blakesmith/ar v0.0.0-20190502131153-809d4375e1fb h1:m935MPodAbYS46DG4pJSv7WO+VECIWUQ7OJYSoTrMh4=
@@ -242,14 +240,6 @@ github.com/cyphar/filepath-securejoin v0.3.6 h1:4d9N5ykBnSp5Xn2JkhocYDkOpURL/18C
 github.com/cyphar/filepath-securejoin v0.3.6/go.mod h1:Sdj7gXlvMcPZsbhwhQ33GguGLDGQL7h7bg04C/+u9jI=
 github.com/daixiang0/gci v0.12.3 h1:yOZI7VAxAGPQmkb1eqt5g/11SUlwoat1fSblGLmdiQc=
 github.com/daixiang0/gci v0.12.3/go.mod h1:xtHP9N7AHdNvtRNfcx9gwTDfw7FRJx4bZUsiEfiNNAI=
-github.com/dave/astrid v0.0.0-20170323122508-8c2895878b14 h1:YI1gOOdmMk3xodBao7fehcvoZsEeOyy/cfhlpCSPgM4=
-github.com/dave/astrid v0.0.0-20170323122508-8c2895878b14/go.mod h1:Sth2QfxfATb/nW4EsrSi2KyJmbcniZ8TgTaji17D6ms=
-github.com/dave/brenda v1.1.0 h1:Sl1LlwXnbw7xMhq3y2x11McFu43AjDcwkllxxgZ3EZw=
-github.com/dave/brenda v1.1.0/go.mod h1:4wCUr6gSlu5/1Tk7akE5X7UorwiQ8Rij0SKH3/BGMOM=
-github.com/dave/courtney v0.4.0 h1:Vb8hi+k3O0h5++BR96FIcX0x3NovRbnhGd/dRr8inBk=
-github.com/dave/courtney v0.4.0/go.mod h1:3WSU3yaloZXYAxRuWt8oRyVb9SaRiMBt5Kz/2J227tM=
-github.com/dave/patsy v0.0.0-20210517141501-957256f50cba h1:1o36L4EKbZzazMk8iGC4kXpVnZ6TPxR2mZ9qVKjNNAs=
-github.com/dave/patsy v0.0.0-20210517141501-957256f50cba/go.mod h1:qfR88CgEGLoiqDaE+xxDCi5QA5v4vUoW0UCX2Nd5Tlc=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc h1:U9qPSI2PIWSS1VwoXQT9A3Wy9MM3WgvqSxFWenqJduM=
@@ -316,8 +306,8 @@ github.com/fxamacker/cbor/v2 v2.7.0 h1:iM5WgngdRBanHcxugY4JySA0nk1wZorNOpTgCMedv
 github.com/fxamacker/cbor/v2 v2.7.0/go.mod h1:pxXPTn3joSm21Gbwsv0w9OSA2y1HFR9qXEeXQVeNoDQ=
 github.com/fzipp/gocyclo v0.6.0 h1:lsblElZG7d3ALtGMx9fmxeTKZaLLpU8mET09yN4BBLo=
 github.com/fzipp/gocyclo v0.6.0/go.mod h1:rXPyn8fnlpa0R2csP/31uerbiVBugk5whMdlyaLkLoA=
-github.com/gaissmai/bart v0.11.1 h1:5Uv5XwsaFBRo4E5VBcb9TzY8B7zxFf+U7isDxqOrRfc=
-github.com/gaissmai/bart v0.11.1/go.mod h1:KHeYECXQiBjTzQz/om2tqn3sZF1J7hw9m6z41ftj3fg=
+github.com/gaissmai/bart v0.18.0 h1:jQLBT/RduJu0pv/tLwXE+xKPgtWJejbxuXAR+wLJafo=
+github.com/gaissmai/bart v0.18.0/go.mod h1:JJzMAhNF5Rjo4SF4jWBrANuJfqY+FvsFhW7t1UZJ+XY=
 github.com/ghostiam/protogetter v0.3.5 h1:+f7UiF8XNd4w3a//4DnusQ2SZjPkUjxkMEfjbxOK4Ug=
 github.com/ghostiam/protogetter v0.3.5/go.mod h1:7lpeDnEJ1ZjL/YtyoN99ljO4z0pd3H0d18/t2dPBxHw=
 github.com/github/fakeca v0.1.0 h1:Km/MVOFvclqxPM9dZBC4+QE564nU4gz4iZ0D9pMw28I=
@@ -337,8 +327,8 @@ github.com/go-git/go-git/v5 v5.13.1/go.mod h1:qryJB4cSBoq3FRoBRf5A77joojuBcmPJ0q
 github.com/go-gl/glfw v0.0.0-20190409004039-e6da0acd62b1/go.mod h1:vR7hzQXu2zJy9AVAgeJqvqgH9Q5CA+iKCZ2gyEVpxRU=
 github.com/go-gl/glfw/v3.3/glfw v0.0.0-20191125211704-12ad95a8df72/go.mod h1:tQ2UAYgL5IevRw8kRxooKSPJfGvJ9fJQFa0TUsXzTg8=
 github.com/go-gl/glfw/v3.3/glfw v0.0.0-20200222043503-6f7a984d4dc4/go.mod h1:tQ2UAYgL5IevRw8kRxooKSPJfGvJ9fJQFa0TUsXzTg8=
-github.com/go-json-experiment/json v0.0.0-20250103232110-6a9a0fde9288 h1:KbX3Z3CgiYlbaavUq3Cj9/MjpO+88S7/AGXzynVDv84=
-github.com/go-json-experiment/json v0.0.0-20250103232110-6a9a0fde9288/go.mod h1:BWmvoE1Xia34f3l/ibJweyhrT+aROb/FQ6d+37F0e2s=
+github.com/go-json-experiment/json v0.0.0-20250223041408-d3c622f1b874 h1:F8d1AJ6M9UQCavhwmO6ZsrYLfG8zVFWfEfMS2MXPkSY=
+github.com/go-json-experiment/json v0.0.0-20250223041408-d3c622f1b874/go.mod h1:TiCD2a1pcmjd7YnhGH0f/zKNcCD06B029pHhzV23c2M=
 github.com/go-kit/kit v0.8.0/go.mod h1:xBxKIO96dXMWWy0MnWVtmwkA9/13aqxPnvrjFYMA2as=
 github.com/go-kit/kit v0.9.0/go.mod h1:xBxKIO96dXMWWy0MnWVtmwkA9/13aqxPnvrjFYMA2as=
 github.com/go-kit/log v0.1.0/go.mod h1:zbhenjAZHb184qTLMA9ZjW7ThYL0H2mk7Q6pNt4vbaY=
@@ -910,8 +900,8 @@ github.com/tailscale/go-winio v0.0.0-20231025203758-c4f33415bf55 h1:Gzfnfk2TWrk8
 github.com/tailscale/go-winio v0.0.0-20231025203758-c4f33415bf55/go.mod h1:4k4QO+dQ3R5FofL+SanAUZe+/QfeK0+OIuwDIRu2vSg=
 github.com/tailscale/goexpect v0.0.0-20210902213824-6e8c725cea41 h1:/V2rCMMWcsjYaYO2MeovLw+ClP63OtXgCF2Y1eb8+Ns=
 github.com/tailscale/goexpect v0.0.0-20210902213824-6e8c725cea41/go.mod h1:/roCdA6gg6lQyw/Oz6gIIGu3ggJKYhF+WC/AQReE5XQ=
-github.com/tailscale/golang-x-crypto v0.0.0-20240604161659-3fde5e568aa4 h1:rXZGgEa+k2vJM8xT0PoSKfVXwFGPQ3z3CJfmnHJkZZw=
-github.com/tailscale/golang-x-crypto v0.0.0-20240604161659-3fde5e568aa4/go.mod h1:ikbF+YT089eInTp9f2vmvy4+ZVnW5hzX1q2WknxSprQ=
+github.com/tailscale/golang-x-crypto v0.0.0-20250218230618-9a281fd8faca h1:ecjHwH73Yvqf/oIdQ2vxAX+zc6caQsYdPzsxNW1J3G8=
+github.com/tailscale/golang-x-crypto v0.0.0-20250218230618-9a281fd8faca/go.mod h1:ikbF+YT089eInTp9f2vmvy4+ZVnW5hzX1q2WknxSprQ=
 github.com/tailscale/goupnp v1.0.1-0.20210804011211-c64d0f06ea05 h1:4chzWmimtJPxRs2O36yuGRW3f9SYV+bMTTvMBI0EKio=
 github.com/tailscale/goupnp v1.0.1-0.20210804011211-c64d0f06ea05/go.mod h1:PdCqy9JzfWMJf1H5UJW2ip33/d4YkoKN0r67yKH1mG8=
 github.com/tailscale/hujson v0.0.0-20221223112325-20486734a56a h1:SJy1Pu0eH1C29XwJucQo73FrleVK6t4kYz4NVhp34Yw=
@@ -1051,8 +1041,8 @@ golang.org/x/crypto v0.0.0-20210921155107-089bfa567519/go.mod h1:GvvjBRRGRdwPK5y
 golang.org/x/crypto v0.0.0-20220622213112-05595931fe9d/go.mod h1:IxCIyHEi3zRg3s0A5j5BB6A9Jmi73HwBIUl50j+osU4=
 golang.org/x/crypto v0.1.0/go.mod h1:RecgLatLF4+eUMCP1PoPZQb+cVrJcOPbHkTkbkB9sbw=
 golang.org/x/crypto v0.3.0/go.mod h1:hebNnKkNXi2UzZN1eVRvBB7co0a+JxK6XbPiWVs/3J4=
-golang.org/x/crypto v0.33.0 h1:IOBPskki6Lysi0lo9qQvbxiQ+FvsCC/YWOecCHAixus=
-golang.org/x/crypto v0.33.0/go.mod h1:bVdXmD7IV/4GdElGPozy6U7lWdRXA4qyRVGJV57uQ5M=
+golang.org/x/crypto v0.35.0 h1:b15kiHdrGCHrP6LvwaQ3c03kgNhhiMgvlhxHQhmg2Xs=
+golang.org/x/crypto v0.35.0/go.mod h1:dy7dXNW32cAb/6/PRuTNsix8T+vJAqvuIy5Bli/x0YQ=
 golang.org/x/exp v0.0.0-20190121172915-509febef88a4/go.mod h1:CJ0aWSM057203Lf6IL+f9T1iT9GByDxfZKAQTCR3kQA=
 golang.org/x/exp v0.0.0-20190306152737-a1d7652674e8/go.mod h1:CJ0aWSM057203Lf6IL+f9T1iT9GByDxfZKAQTCR3kQA=
 golang.org/x/exp v0.0.0-20190510132918-efd6b22b2522/go.mod h1:ZjyILWgesfNpC6sMxTJOJm9Kp84zZh5NQWvqDGG3Qr8=

go.toolchain.branch

@@ -1 +1 @@
-tailscale.go1.23
+tailscale.go1.24

go.toolchain.rev

@@ -1 +1 @@
-65c3f5f3fc9d96f56a37a79cad4ebbd7ff985801
+2b494987ff3c1a6a26e10570c490394ff0a77aa4

internal/client/tailscale/tailscale.go

@@ -0,0 +1,83 @@
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
+
+// Package tailscale provides a minimal control plane API client for internal
+// use. A full client for 3rd party use is available at
+// tailscale.com/client/tailscale/v2. The internal client is provided to avoid
+// having to import that whole package.
+package tailscale
+
+import (
+	"errors"
+	"io"
+	"net/http"
+
+	tsclient "tailscale.com/client/tailscale"
+)
+
+// maxSize is the maximum read size (10MB) of responses from the server.
+const maxReadSize = 10 << 20
+
+func init() {
+	tsclient.I_Acknowledge_This_API_Is_Unstable = true
+}
+
+// AuthMethod is an alias to tailscale.com/client/tailscale.
+type AuthMethod = tsclient.AuthMethod
+
+// Device is an alias to tailscale.com/client/tailscale.
+type Device = tsclient.Device
+
+// DeviceFieldsOpts is an alias to tailscale.com/client/tailscale.
+type DeviceFieldsOpts = tsclient.DeviceFieldsOpts
+
+// Key is an alias to tailscale.com/client/tailscale.
+type Key = tsclient.Key
+
+// KeyCapabilities is an alias to tailscale.com/client/tailscale.
+type KeyCapabilities = tsclient.KeyCapabilities
+
+// KeyDeviceCapabilities is an alias to tailscale.com/client/tailscale.
+type KeyDeviceCapabilities = tsclient.KeyDeviceCapabilities
+
+// KeyDeviceCreateCapabilities is an alias to tailscale.com/client/tailscale.
+type KeyDeviceCreateCapabilities = tsclient.KeyDeviceCreateCapabilities
+
+// ErrResponse is an alias to tailscale.com/client/tailscale.
+type ErrResponse = tsclient.ErrResponse
+
+// NewClient is an alias to tailscale.com/client/tailscale.
+func NewClient(tailnet string, auth AuthMethod) *Client {
+	return &Client{
+		Client: tsclient.NewClient(tailnet, auth),
+	}
+}
+
+// Client is a wrapper of tailscale.com/client/tailscale.
+type Client struct {
+	*tsclient.Client
+}
+
+// HandleErrorResponse is an alias to tailscale.com/client/tailscale.
+func HandleErrorResponse(b []byte, resp *http.Response) error {
+	return tsclient.HandleErrorResponse(b, resp)
+}
+
+// SendRequest add the authentication key to the request and sends it. It
+// receives the response and reads up to 10MB of it.
+func SendRequest(c *Client, req *http.Request) ([]byte, *http.Response, error) {
+	resp, err := c.Do(req)
+	if err != nil {
+		return nil, resp, err
+	}
+	defer resp.Body.Close()
+
+	// Read response. Limit the response to 10MB.
+	// This limit is carried over from client/tailscale/tailscale.go.
+	body := io.LimitReader(resp.Body, maxReadSize+1)
+	b, err := io.ReadAll(body)
+	if len(b) > maxReadSize {
+		err = errors.New("API response too large")
+	}
+	return b, resp, err
+}

internal/client/tailscale/vip_service.go

@@ -0,0 +1,103 @@
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
+
+package tailscale
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"fmt"
+	"net/http"
+
+	"tailscale.com/tailcfg"
+	"tailscale.com/util/httpm"
+)
+
+// VIPService is a Tailscale VIPService with Tailscale API JSON representation.
+type VIPService struct {
+	// Name is a VIPService name in form svc:<leftmost-label-of-service-DNS-name>.
+	Name tailcfg.ServiceName `json:"name,omitempty"`
+	// Addrs are the IP addresses of the VIP Service. There are two addresses:
+	// the first is IPv4 and the second is IPv6.
+	// When creating a new VIP Service, the IP addresses are optional: if no
+	// addresses are specified then they will be selected. If an IPv4 address is
+	// specified at index 0, then that address will attempt to be used. An IPv6
+	// address can not be specified upon creation.
+	Addrs []string `json:"addrs,omitempty"`
+	// Comment is an optional text string for display in the admin panel.
+	Comment string `json:"comment,omitempty"`
+	// Ports are the ports of a VIPService that will be configured via Tailscale serve config.
+	// If set, any node wishing to advertise this VIPService must have this port configured via Tailscale serve.
+	Ports []string `json:"ports,omitempty"`
+	// Tags are optional ACL tags that will be applied to the VIPService.
+	Tags []string `json:"tags,omitempty"`
+}
+
+// GetVIPService retrieves a VIPService by its name. It returns 404 if the VIPService is not found.
+func (client *Client) GetVIPService(ctx context.Context, name tailcfg.ServiceName) (*VIPService, error) {
+	path := client.BuildTailnetURL("vip-services", name.String())
+	req, err := http.NewRequestWithContext(ctx, httpm.GET, path, nil)
+	if err != nil {
+		return nil, fmt.Errorf("error creating new HTTP request: %w", err)
+	}
+	b, resp, err := SendRequest(client, req)
+	if err != nil {
+		return nil, fmt.Errorf("error making Tailsale API request: %w", err)
+	}
+	// If status code was not successful, return the error.
+	// TODO: Change the check for the StatusCode to include other 2XX success codes.
+	if resp.StatusCode != http.StatusOK {
+		return nil, HandleErrorResponse(b, resp)
+	}
+	svc := &VIPService{}
+	if err := json.Unmarshal(b, svc); err != nil {
+		return nil, err
+	}
+	return svc, nil
+}
+
+// CreateOrUpdateVIPService creates or updates a VIPService by its name. Caller must ensure that, if the
+// VIPService already exists, the VIPService is fetched first to ensure that any auto-allocated IP addresses are not
+// lost during the update. If the VIPService was created without any IP addresses explicitly set (so that they were
+// auto-allocated by Tailscale) any subsequent request to this function that does not set any IP addresses will error.
+func (client *Client) CreateOrUpdateVIPService(ctx context.Context, svc *VIPService) error {
+	data, err := json.Marshal(svc)
+	if err != nil {
+		return err
+	}
+	path := client.BuildTailnetURL("vip-services", svc.Name.String())
+	req, err := http.NewRequestWithContext(ctx, httpm.PUT, path, bytes.NewBuffer(data))
+	if err != nil {
+		return fmt.Errorf("error creating new HTTP request: %w", err)
+	}
+	b, resp, err := SendRequest(client, req)
+	if err != nil {
+		return fmt.Errorf("error making Tailscale API request: %w", err)
+	}
+	// If status code was not successful, return the error.
+	// TODO: Change the check for the StatusCode to include other 2XX success codes.
+	if resp.StatusCode != http.StatusOK {
+		return HandleErrorResponse(b, resp)
+	}
+	return nil
+}
+
+// DeleteVIPService deletes a VIPService by its name. It returns an error if the VIPService
+// does not exist or if the deletion fails.
+func (client *Client) DeleteVIPService(ctx context.Context, name tailcfg.ServiceName) error {
+	path := client.BuildTailnetURL("vip-services", name.String())
+	req, err := http.NewRequestWithContext(ctx, httpm.DELETE, path, nil)
+	if err != nil {
+		return fmt.Errorf("error creating new HTTP request: %w", err)
+	}
+	b, resp, err := SendRequest(client, req)
+	if err != nil {
+		return fmt.Errorf("error making Tailscale API request: %w", err)
+	}
+	// If status code was not successful, return the error.
+	if resp.StatusCode != http.StatusOK {
+		return HandleErrorResponse(b, resp)
+	}
+	return nil
+}

ipn/desktop/sessions_windows.go

@@ -359,7 +359,7 @@ func (sw *sessionWatcher) Start() error {
 	sw.doneCh = make(chan error, 1)
 
 	startedCh := make(chan error, 1)
-	go sw.run(startedCh)
+	go sw.run(startedCh, sw.doneCh)
 	if err := <-startedCh; err != nil {
 		return err
 	}
@@ -372,11 +372,11 @@ func (sw *sessionWatcher) Start() error {
 	return nil
 }
 
-func (sw *sessionWatcher) run(started chan<- error) {
+func (sw *sessionWatcher) run(started, done chan<- error) {
 	runtime.LockOSThread()
 	defer func() {
 		runtime.UnlockOSThread()
-		close(sw.doneCh)
+		close(done)
 	}()
 	err := sw.createMessageWindow()
 	started <- err

ipn/ipnlocal/desktop_sessions.go

@@ -0,0 +1,178 @@
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
+
+// Both the desktop session manager and multi-user support
+// are currently available only on Windows.
+// This file does not need to be built for other platforms.
+
+//go:build windows && !ts_omit_desktop_sessions
+
+package ipnlocal
+
+import (
+	"cmp"
+	"errors"
+	"fmt"
+	"sync"
+
+	"tailscale.com/feature"
+	"tailscale.com/ipn"
+	"tailscale.com/ipn/desktop"
+	"tailscale.com/tsd"
+	"tailscale.com/types/logger"
+	"tailscale.com/util/syspolicy"
+)
+
+func init() {
+	feature.Register("desktop-sessions")
+	RegisterExtension("desktop-sessions", newDesktopSessionsExt)
+}
+
+// desktopSessionsExt implements [localBackendExtension].
+var _ localBackendExtension = (*desktopSessionsExt)(nil)
+
+// desktopSessionsExt extends [LocalBackend] with desktop session management.
+// It keeps Tailscale running in the background if Always-On mode is enabled,
+// and switches to an appropriate profile when a user signs in or out,
+// locks their screen, or disconnects a remote session.
+type desktopSessionsExt struct {
+	logf logger.Logf
+	sm   desktop.SessionManager
+
+	*LocalBackend          // or nil, until Init is called
+	cleanup       []func() // cleanup functions to call on shutdown
+
+	// mu protects all following fields.
+	// When both mu and [LocalBackend.mu] need to be taken,
+	// [LocalBackend.mu] must be taken before mu.
+	mu      sync.Mutex
+	id2sess map[desktop.SessionID]*desktop.Session
+}
+
+// newDesktopSessionsExt returns a new [desktopSessionsExt],
+// or an error if [desktop.SessionManager] is not available.
+func newDesktopSessionsExt(logf logger.Logf, sys *tsd.System) (localBackendExtension, error) {
+	sm, ok := sys.SessionManager.GetOK()
+	if !ok {
+		return nil, errors.New("session manager is not available")
+	}
+	return &desktopSessionsExt{logf: logf, sm: sm, id2sess: make(map[desktop.SessionID]*desktop.Session)}, nil
+}
+
+// Init implements [localBackendExtension].
+func (e *desktopSessionsExt) Init(lb *LocalBackend) (err error) {
+	e.LocalBackend = lb
+	unregisterResolver := lb.RegisterBackgroundProfileResolver(e.getBackgroundProfile)
+	unregisterSessionCb, err := e.sm.RegisterStateCallback(e.updateDesktopSessionState)
+	if err != nil {
+		unregisterResolver()
+		return fmt.Errorf("session callback registration failed: %w", err)
+	}
+	e.cleanup = []func(){unregisterResolver, unregisterSessionCb}
+	return nil
+}
+
+// updateDesktopSessionState is a [desktop.SessionStateCallback]
+// invoked by [desktop.SessionManager] once for each existing session
+// and whenever the session state changes. It updates the session map
+// and switches to the best profile if necessary.
+func (e *desktopSessionsExt) updateDesktopSessionState(session *desktop.Session) {
+	e.mu.Lock()
+	if session.Status != desktop.ClosedSession {
+		e.id2sess[session.ID] = session
+	} else {
+		delete(e.id2sess, session.ID)
+	}
+	e.mu.Unlock()
+
+	var action string
+	switch session.Status {
+	case desktop.ForegroundSession:
+		// The user has either signed in or unlocked their session.
+		// For remote sessions, this may also mean the user has connected.
+		// The distinction isn't important for our purposes,
+		// so let's always say "signed in".
+		action = "signed in to"
+	case desktop.BackgroundSession:
+		action = "locked"
+	case desktop.ClosedSession:
+		action = "signed out from"
+	default:
+		panic("unreachable")
+	}
+	maybeUsername, _ := session.User.Username()
+	userIdentifier := cmp.Or(maybeUsername, string(session.User.UserID()), "user")
+	reason := fmt.Sprintf("%s %s session %v", userIdentifier, action, session.ID)
+
+	e.SwitchToBestProfile(reason)
+}
+
+// getBackgroundProfile is a [profileResolver] that works as follows:
+//
+// If Always-On mode is disabled, it returns no profile ("","",false).
+//
+// If AlwaysOn mode is enabled, it returns the current profile unless:
+// - The current user has signed out.
+// - Another user has a foreground (i.e. active/unlocked) session.
+//
+// If the current user's session runs in the background and no other user
+// has a foreground session, it returns the current profile. This applies
+// when a locally signed-in user locks their screen or when a remote user
+// disconnects without signing out.
+//
+// In all other cases, it returns no profile ("","",false).
+//
+// It is called with [LocalBackend.mu] locked.
+func (e *desktopSessionsExt) getBackgroundProfile() (_ ipn.WindowsUserID, _ ipn.ProfileID, ok bool) {
+	e.mu.Lock()
+	defer e.mu.Unlock()
+
+	if alwaysOn, _ := syspolicy.GetBoolean(syspolicy.AlwaysOn, false); !alwaysOn {
+		return "", "", false
+	}
+
+	isCurrentUserSingedIn := false
+	var foregroundUIDs []ipn.WindowsUserID
+	for _, s := range e.id2sess {
+		switch uid := s.User.UserID(); uid {
+		case e.pm.CurrentUserID():
+			isCurrentUserSingedIn = true
+			if s.Status == desktop.ForegroundSession {
+				// Keep the current profile if the user has a foreground session.
+				return e.pm.CurrentUserID(), e.pm.CurrentProfile().ID(), true
+			}
+		default:
+			if s.Status == desktop.ForegroundSession {
+				foregroundUIDs = append(foregroundUIDs, uid)
+			}
+		}
+	}
+
+	// If there's no current user (e.g., tailscaled just started), or if the current
+	// user has no foreground session, switch to the default profile of the first user
+	// with a foreground session, if any.
+	for _, uid := range foregroundUIDs {
+		if profileID := e.pm.DefaultUserProfileID(uid); profileID != "" {
+			return uid, profileID, true
+		}
+	}
+
+	// If no user has a foreground session but the current user is still signed in,
+	// keep the current profile even if the session is not in the foreground,
+	// such as when the screen is locked or a remote session is disconnected.
+	if len(foregroundUIDs) == 0 && isCurrentUserSingedIn {
+		return e.pm.CurrentUserID(), e.pm.CurrentProfile().ID(), true
+	}
+
+	return "", "", false
+}
+
+// Shutdown implements [localBackendExtension].
+func (e *desktopSessionsExt) Shutdown() error {
+	for _, f := range e.cleanup {
+		f()
+	}
+	e.cleanup = nil
+	e.LocalBackend = nil
+	return nil
+}

ipn/ipnlocal/local.go

@@ -168,6 +168,49 @@ type watchSession struct {
 	cancel    context.CancelFunc // to shut down the session
 }
 
+// localBackendExtension extends [LocalBackend] with additional functionality.
+type localBackendExtension interface {
+	// Init is called to initialize the extension when the [LocalBackend] is created
+	// and before it starts running. If the extension cannot be initialized,
+	// it must return an error, and the Shutdown method will not be called.
+	// Any returned errors are not fatal; they are used for logging.
+	// TODO(nickkhyl): should we allow returning a fatal error?
+	Init(*LocalBackend) error
+
+	// Shutdown is called when the [LocalBackend] is shutting down,
+	// if the extension was initialized. Any returned errors are not fatal;
+	// they are used for logging.
+	Shutdown() error
+}
+
+// newLocalBackendExtension is a function that instantiates a [localBackendExtension].
+type newLocalBackendExtension func(logger.Logf, *tsd.System) (localBackendExtension, error)
+
+// registeredExtensions is a map of registered local backend extensions,
+// where the key is the name of the extension and the value is the function
+// that instantiates the extension.
+var registeredExtensions map[string]newLocalBackendExtension
+
+// RegisterExtension registers a function that creates a [localBackendExtension].
+// It panics if newExt is nil or if an extension with the same name has already been registered.
+func RegisterExtension(name string, newExt newLocalBackendExtension) {
+	if newExt == nil {
+		panic(fmt.Sprintf("lb: newExt is nil: %q", name))
+	}
+	if _, ok := registeredExtensions[name]; ok {
+		panic(fmt.Sprintf("lb: duplicate extensions: %q", name))
+	}
+	mak.Set(&registeredExtensions, name, newExt)
+}
+
+// profileResolver is any function that returns user and profile IDs
+// along with a flag indicating whether it succeeded. Since an empty
+// profile ID ("") represents an empty profile, the ok return parameter
+// distinguishes between an empty profile and no profile.
+//
+// It is called with [LocalBackend.mu] held.
+type profileResolver func() (_ ipn.WindowsUserID, _ ipn.ProfileID, ok bool)
+
 // LocalBackend is the glue between the major pieces of the Tailscale
 // network software: the cloud control plane (via controlclient), the
 // network data plane (via wgengine), and the user-facing UIs and CLIs
@@ -302,8 +345,12 @@ type LocalBackend struct {
 	directFileRoot    string
 	componentLogUntil map[string]componentLogState
 	// c2nUpdateStatus is the status of c2n-triggered client update.
-	c2nUpdateStatus     updateStatus
-	currentUser         ipnauth.Actor
+	c2nUpdateStatus updateStatus
+	currentUser     ipnauth.Actor
+
+	// backgroundProfileResolvers are optional background profile resolvers.
+	backgroundProfileResolvers set.HandleSet[profileResolver]
+
 	selfUpdateProgress  []ipnstate.UpdateProgress
 	lastSelfUpdateState ipnstate.SelfUpdateStatus
 	// capForcedNetfilter is the netfilter that control instructs Linux clients
@@ -394,6 +441,15 @@ type LocalBackend struct {
 	// and the user has disconnected with a reason.
 	// See tailscale/corp#26146.
 	overrideAlwaysOn bool
+
+	// reconnectTimer is used to schedule a reconnect by setting [ipn.Prefs.WantRunning]
+	// to true after a delay, or nil if no reconnect is scheduled.
+	reconnectTimer tstime.TimerController
+
+	// shutdownCbs are the callbacks to be called when the backend is shutting down.
+	// Each callback is called exactly once in unspecified order and without b.mu held.
+	// Returned errors are logged but otherwise ignored and do not affect the shutdown process.
+	shutdownCbs set.HandleSet[func() error]
 }
 
 // HealthTracker returns the health tracker for the backend.
@@ -575,6 +631,19 @@ func NewLocalBackend(logf logger.Logf, logID logid.PublicID, sys *tsd.System, lo
 		}
 	}
 
+	for name, newFn := range registeredExtensions {
+		ext, err := newFn(logf, sys)
+		if err != nil {
+			b.logf("lb: failed to create %q extension: %v", name, err)
+			continue
+		}
+		if err := ext.Init(b); err != nil {
+			b.logf("lb: failed to initialize %q extension: %v", name, err)
+			continue
+		}
+		b.shutdownCbs.Add(ext.Shutdown)
+	}
+
 	return b, nil
 }
 
@@ -1005,6 +1074,8 @@ func (b *LocalBackend) Shutdown() {
 		b.captiveCancel()
 	}
 
+	b.stopReconnectTimerLocked()
+
 	if b.loginFlags&controlclient.LoginEphemeral != 0 {
 		b.mu.Unlock()
 		ctx, cancel := context.WithTimeout(b.ctx, 5*time.Second)
@@ -1033,9 +1104,17 @@ func (b *LocalBackend) Shutdown() {
 	if b.notifyCancel != nil {
 		b.notifyCancel()
 	}
+	shutdownCbs := slices.Collect(maps.Values(b.shutdownCbs))
+	b.shutdownCbs = nil
 	b.mu.Unlock()
 	b.webClientShutdown()
 
+	for _, cb := range shutdownCbs {
+		if err := cb(); err != nil {
+			b.logf("shutdown callback failed: %v", err)
+		}
+	}
+
 	if b.sockstatLogger != nil {
 		ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
 		defer cancel()
@@ -1256,6 +1335,7 @@ func (b *LocalBackend) populatePeerStatusLocked(sb *ipnstate.StatusBuilder) {
 			SSH_HostKeys:    p.Hostinfo().SSH_HostKeys().AsSlice(),
 			Location:        p.Hostinfo().Location().AsStruct(),
 			Capabilities:    p.Capabilities().AsSlice(),
+			TaildropTarget:  b.taildropTargetStatus(p),
 		}
 		if cm := p.CapMap(); cm.Len() > 0 {
 			ps.CapMap = make(tailcfg.NodeCapMap, cm.Len())
@@ -1438,6 +1518,10 @@ func (b *LocalBackend) peerCapsLocked(src netip.Addr) tailcfg.PeerCapMap {
 	return nil
 }
 
+func (b *LocalBackend) GetFilterForTest() *filter.Filter {
+	return b.filterAtomic.Load()
+}
+
 // SetControlClientStatus is the callback invoked by the control client whenever it posts a new status.
 // Among other things, this is where we update the netmap, packet filters, DNS and DERP maps.
 func (b *LocalBackend) SetControlClientStatus(c controlclient.Client, st controlclient.Status) {
@@ -2263,12 +2347,20 @@ func (b *LocalBackend) Start(opts ipn.Options) error {
 		}); err != nil {
 			b.logf("failed to save UpdatePrefs state: %v", err)
 		}
-		b.setAtomicValuesFromPrefsLocked(pv)
-	} else {
-		b.setAtomicValuesFromPrefsLocked(b.pm.CurrentPrefs())
 	}
 
+	// Reset the always-on override whenever Start is called.
+	b.resetAlwaysOnOverrideLocked()
+	// And also apply syspolicy settings to the current profile.
+	// This is important in two cases: when opts.UpdatePrefs is not nil,
+	// and when Always Mode is enabled and we need to set WantRunning to true.
+	if newp := b.pm.CurrentPrefs().AsStruct(); applySysPolicy(newp, b.lastSuggestedExitNode, b.overrideAlwaysOn) {
+		setExitNodeID(newp, b.netMap)
+		b.pm.setPrefsNoPermCheck(newp.View())
+	}
 	prefs := b.pm.CurrentPrefs()
+	b.setAtomicValuesFromPrefsLocked(prefs)
+
 	wantRunning := prefs.WantRunning()
 	if wantRunning {
 		if err := b.initMachineKeyLocked(); err != nil {
@@ -3795,14 +3887,15 @@ func (b *LocalBackend) shouldUploadServices() bool {
 //
 // On non-multi-user systems, the actor should be set to nil.
 func (b *LocalBackend) SetCurrentUser(actor ipnauth.Actor) {
-	var uid ipn.WindowsUserID
-	if actor != nil {
-		uid = actor.UserID()
-	}
-
 	unlock := b.lockAndGetUnlock()
 	defer unlock()
 
+	var userIdentifier string
+	if user := cmp.Or(actor, b.currentUser); user != nil {
+		maybeUsername, _ := user.Username()
+		userIdentifier = cmp.Or(maybeUsername, string(user.UserID()))
+	}
+
 	if actor != b.currentUser {
 		if c, ok := b.currentUser.(ipnauth.ActorCloser); ok {
 			c.Close()
@@ -3810,50 +3903,146 @@ func (b *LocalBackend) SetCurrentUser(actor ipnauth.Actor) {
 		b.currentUser = actor
 	}
 
-	if b.pm.CurrentUserID() == uid {
-		return
-	}
-
-	var profileID ipn.ProfileID
-	if actor != nil {
-		profileID = b.pm.DefaultUserProfileID(uid)
-	} else if uid, profileID = b.getBackgroundProfileIDLocked(); profileID != "" {
-		b.logf("client disconnected; staying alive in server mode")
+	var action string
+	if actor == nil {
+		action = "disconnected"
 	} else {
-		b.logf("client disconnected; stopping server")
-	}
-
-	if err := b.switchProfileLockedOnEntry(uid, profileID, unlock); err != nil {
-		b.logf("failed switching profile to %q: %v", profileID, err)
+		action = "connected"
 	}
+	reason := fmt.Sprintf("client %s (%s)", action, userIdentifier)
+	b.switchToBestProfileLockedOnEntry(reason, unlock)
 }
 
-// switchProfileLockedOnEntry is like [LocalBackend.SwitchProfile],
-// but b.mu must held on entry, but it is released on exit.
-func (b *LocalBackend) switchProfileLockedOnEntry(uid ipn.WindowsUserID, profileID ipn.ProfileID, unlock unlockOnce) error {
+// SwitchToBestProfile selects the best profile to use,
+// as reported by [LocalBackend.resolveBestProfileLocked], and switches
+// to it, unless it's already the current profile. The reason indicates
+// why the profile is being switched, such as due to a client connecting
+// or disconnecting, or a change in the desktop session state, and is used
+// for logging.
+func (b *LocalBackend) SwitchToBestProfile(reason string) {
+	b.switchToBestProfileLockedOnEntry(reason, b.lockAndGetUnlock())
+}
+
+// switchToBestProfileLockedOnEntry is like [LocalBackend.SwitchToBestProfile],
+// but b.mu must held on entry. It is released on exit.
+func (b *LocalBackend) switchToBestProfileLockedOnEntry(reason string, unlock unlockOnce) {
 	defer unlock()
-	if b.pm.CurrentUserID() == uid && b.pm.CurrentProfile().ID() == profileID {
-		return nil
-	}
 	oldControlURL := b.pm.CurrentPrefs().ControlURLOrDefault()
-	if changed := b.pm.SetCurrentUserAndProfile(uid, profileID); !changed {
-		return nil
+	uid, profileID, background := b.resolveBestProfileLocked()
+	cp, switched := b.pm.SetCurrentUserAndProfile(uid, profileID)
+	switch {
+	case !switched && cp.ID() == "":
+		b.logf("%s: staying on empty profile", reason)
+	case !switched:
+		b.logf("%s: staying on profile %q (%s)", reason, cp.UserProfile().LoginName, cp.ID())
+	case cp.ID() == "":
+		b.logf("%s: disconnecting Tailscale", reason)
+	case background:
+		b.logf("%s: switching to background profile %q (%s)", reason, cp.UserProfile().LoginName, cp.ID())
+	default:
+		b.logf("%s: switching to profile %q (%s)", reason, cp.UserProfile().LoginName, cp.ID())
+	}
+	if !switched {
+		return
 	}
 	// As an optimization, only reset the dialPlan if the control URL changed.
 	if newControlURL := b.pm.CurrentPrefs().ControlURLOrDefault(); oldControlURL != newControlURL {
 		b.resetDialPlan()
 	}
-	return b.resetForProfileChangeLockedOnEntry(unlock)
+	if err := b.resetForProfileChangeLockedOnEntry(unlock); err != nil {
+		// TODO(nickkhyl): The actual reset cannot fail. However,
+		// the TKA initialization or [LocalBackend.Start] can fail.
+		// These errors are not critical as far as we're concerned.
+		// But maybe we should post a notification to the API watchers?
+		b.logf("failed switching profile to %q: %v", profileID, err)
+	}
 }
 
-// getBackgroundProfileIDLocked returns the profile ID to use when no GUI/CLI
-// client is connected, or "" if Tailscale should not run in the background.
+// resolveBestProfileLocked returns the best profile to use based on the current
+// state of the backend, such as whether a GUI/CLI client is connected, whether
+// the unattended mode is enabled, the current state of the desktop sessions,
+// and other factors.
+//
+// It returns the user ID, profile ID, and whether the returned profile is
+// considered a background profile. A background profile is used when no OS user
+// is actively using Tailscale, such as when no GUI/CLI client is connected
+// and Unattended Mode is enabled (see also [LocalBackend.getBackgroundProfileLocked]).
+// An empty profile ID indicates that Tailscale should switch to an empty profile.
+//
+// b.mu must be held.
+func (b *LocalBackend) resolveBestProfileLocked() (userID ipn.WindowsUserID, profileID ipn.ProfileID, isBackground bool) {
+	// If a GUI/CLI client is connected, use the connected user's profile, which means
+	// either the current profile if owned by the user, or their default profile.
+	if b.currentUser != nil {
+		cp := b.pm.CurrentProfile()
+		uid := b.currentUser.UserID()
+
+		var profileID ipn.ProfileID
+		// TODO(nickkhyl): check if the current profile is allowed on the device,
+		// such as when [syspolicy.Tailnet] policy setting requires a specific Tailnet.
+		// See tailscale/corp#26249.
+		if cp.LocalUserID() == uid {
+			profileID = cp.ID()
+		} else {
+			profileID = b.pm.DefaultUserProfileID(uid)
+		}
+		return uid, profileID, false
+	}
+
+	// Otherwise, if on Windows, use the background profile if one is set.
+	// This includes staying on the current profile if Unattended Mode is enabled
+	// or if AlwaysOn mode is enabled and the current user is still signed in.
+	// If the returned background profileID is "", Tailscale will disconnect
+	// and remain idle until a GUI or CLI client connects.
+	if goos := envknob.GOOS(); goos == "windows" {
+		uid, profileID := b.getBackgroundProfileLocked()
+		return uid, profileID, true
+	}
+
+	// On other platforms, however, Tailscale continues to run in the background
+	// using the current profile.
+	//
+	// TODO(nickkhyl): check if the current profile is allowed on the device,
+	// such as when [syspolicy.Tailnet] policy setting requires a specific Tailnet.
+	// See tailscale/corp#26249.
+	return b.pm.CurrentUserID(), b.pm.CurrentProfile().ID(), false
+}
+
+// RegisterBackgroundProfileResolver registers a function to be used when
+// resolving the background profile, until the returned unregister function is called.
+func (b *LocalBackend) RegisterBackgroundProfileResolver(resolver profileResolver) (unregister func()) {
+	// TODO(nickkhyl): should we allow specifying some kind of priority/altitude for the resolver?
+	b.mu.Lock()
+	defer b.mu.Unlock()
+	handle := b.backgroundProfileResolvers.Add(resolver)
+	return func() {
+		b.mu.Lock()
+		defer b.mu.Unlock()
+		delete(b.backgroundProfileResolvers, handle)
+	}
+}
+
+// getBackgroundProfileLocked returns the user and profile ID to use when no GUI/CLI
+// client is connected, or "","" if Tailscale should not run in the background.
 // As of 2025-02-07, it is only used on Windows.
-func (b *LocalBackend) getBackgroundProfileIDLocked() (ipn.WindowsUserID, ipn.ProfileID) {
+func (b *LocalBackend) getBackgroundProfileLocked() (ipn.WindowsUserID, ipn.ProfileID) {
+	// TODO(nickkhyl): check if the returned profile is allowed on the device,
+	// such as when [syspolicy.Tailnet] policy setting requires a specific Tailnet.
+	// See tailscale/corp#26249.
+
 	// If Unattended Mode is enabled for the current profile, keep using it.
 	if b.pm.CurrentPrefs().ForceDaemon() {
 		return b.pm.CurrentProfile().LocalUserID(), b.pm.CurrentProfile().ID()
 	}
+
+	// Otherwise, attempt to resolve the background profile using the background
+	// profile resolvers available on the current platform.
+	for _, resolver := range b.backgroundProfileResolvers {
+		if uid, profileID, ok := resolver(); ok {
+			return uid, profileID
+		}
+	}
+
 	// Otherwise, switch to an empty profile and disconnect Tailscale
 	// until a GUI or CLI client connects.
 	return "", ""
@@ -4114,15 +4303,75 @@ func (b *LocalBackend) EditPrefsAs(mp *ipn.MaskedPrefs, actor ipnauth.Actor) (ip
 		// mode on them until the policy changes, they switch to a different profile, etc.
 		b.overrideAlwaysOn = true
 
-		// TODO(nickkhyl): check the ReconnectAfter policy here. If configured,
-		// start a timer to automatically reconnect after the specified duration.
+		if reconnectAfter, _ := syspolicy.GetDuration(syspolicy.ReconnectAfter, 0); reconnectAfter > 0 {
+			b.startReconnectTimerLocked(reconnectAfter)
+		}
 	}
 
 	return b.editPrefsLockedOnEntry(mp, unlock)
 }
 
+// startReconnectTimerLocked sets a timer to automatically set WantRunning to true
+// after the specified duration.
+func (b *LocalBackend) startReconnectTimerLocked(d time.Duration) {
+	if b.reconnectTimer != nil {
+		// Stop may return false if the timer has already fired,
+		// and the function has been called in its own goroutine,
+		// but lost the race to acquire b.mu. In this case, it'll
+		// end up as a no-op due to a reconnectTimer mismatch
+		// once it manages to acquire the lock. This is fine, and we
+		// don't need to check the return value.
+		b.reconnectTimer.Stop()
+	}
+	profileID := b.pm.CurrentProfile().ID()
+	var reconnectTimer tstime.TimerController
+	reconnectTimer = b.clock.AfterFunc(d, func() {
+		unlock := b.lockAndGetUnlock()
+		defer unlock()
+
+		if b.reconnectTimer != reconnectTimer {
+			// We're either not the most recent timer, or we lost the race when
+			// the timer was stopped. No need to reconnect.
+			return
+		}
+		b.reconnectTimer = nil
+
+		cp := b.pm.CurrentProfile()
+		if cp.ID() != profileID {
+			// The timer fired before the profile changed but we lost the race
+			// and acquired the lock shortly after.
+			// No need to reconnect.
+			return
+		}
+
+		mp := &ipn.MaskedPrefs{WantRunningSet: true, Prefs: ipn.Prefs{WantRunning: true}}
+		if _, err := b.editPrefsLockedOnEntry(mp, unlock); err != nil {
+			b.logf("failed to automatically reconnect as %q after %v: %v", cp.Name(), d, err)
+		} else {
+			b.logf("automatically reconnected as %q after %v", cp.Name(), d)
+		}
+	})
+	b.reconnectTimer = reconnectTimer
+	b.logf("reconnect for %q has been scheduled and will be performed in %v", b.pm.CurrentProfile().Name(), d)
+}
+
 func (b *LocalBackend) resetAlwaysOnOverrideLocked() {
 	b.overrideAlwaysOn = false
+	b.stopReconnectTimerLocked()
+}
+
+func (b *LocalBackend) stopReconnectTimerLocked() {
+	if b.reconnectTimer != nil {
+		// Stop may return false if the timer has already fired,
+		// and the function has been called in its own goroutine,
+		// but lost the race to acquire b.mu.
+		// In this case, it'll end up as a no-op due to a reconnectTimer
+		// mismatch (see [LocalBackend.startReconnectTimerLocked])
+		// once it manages to acquire the lock. This is fine, and we
+		// don't need to check the return value.
+		b.reconnectTimer.Stop()
+		b.reconnectTimer = nil
+	}
 }
 
 // Warning: b.mu must be held on entry, but it unlocks it on the way out.
@@ -4197,6 +4446,12 @@ func (b *LocalBackend) hasIngressEnabledLocked() bool {
 	return b.serveConfig.Valid() && b.serveConfig.IsFunnelOn()
 }
 
+// shouldWireInactiveIngressLocked reports whether the node is in a state where funnel is not actively enabled, but it
+// seems that it is intended to be used with funnel.
+func (b *LocalBackend) shouldWireInactiveIngressLocked() bool {
+	return b.serveConfig.Valid() && !b.hasIngressEnabledLocked() && b.wantIngressLocked()
+}
+
 // setPrefsLockedOnEntry requires b.mu be held to call it, but it
 // unlocks b.mu when done. newp ownership passes to this function.
 // It returns a read-only copy of the new prefs.
@@ -4210,7 +4465,7 @@ func (b *LocalBackend) setPrefsLockedOnEntry(newp *ipn.Prefs, unlock unlockOnce)
 	if oldp.Valid() {
 		newp.Persist = oldp.Persist().AsStruct() // caller isn't allowed to override this
 	}
-	// applySysPolicyToPrefsLocked returns whether it updated newp,
+	// applySysPolicy returns whether it updated newp,
 	// but everything in this function treats b.prefs as completely new
 	// anyway, so its return value can be ignored here.
 	applySysPolicy(newp, b.lastSuggestedExitNode, b.overrideAlwaysOn)
@@ -5304,18 +5559,18 @@ func (b *LocalBackend) applyPrefsToHostinfoLocked(hi *tailcfg.Hostinfo, prefs ip
 
 	hi.ServicesHash = b.vipServiceHash(b.vipServicesFromPrefsLocked(prefs))
 
-	// The Hostinfo.WantIngress field tells control whether this node wants to
-	// be wired up for ingress connections. If harmless if it's accidentally
-	// true; the actual policy is controlled in tailscaled by ServeConfig. But
-	// if this is accidentally false, then control may not configure DNS
-	// properly. This exists as an optimization to control to program fewer DNS
-	// records that have ingress enabled but are not actually being used.
-	// TODO(irbekrm): once control knows that if hostinfo.IngressEnabled is true,
-	// then wireIngress can be considered true, don't send wireIngress in that case.
-	hi.WireIngress = b.wantIngressLocked()
 	// The Hostinfo.IngressEnabled field is used to communicate to control whether
-	// the funnel is actually enabled.
+	// the node has funnel enabled.
 	hi.IngressEnabled = b.hasIngressEnabledLocked()
+	// The Hostinfo.WantIngress field tells control whether the user intends
+	// to use funnel with this node even though it is not currently enabled.
+	// This is an optimization to control- Funnel requires creation of DNS
+	// records and because DNS propagation can take time, we want to ensure
+	// that the records exist for any node that intends to use funnel even
+	// if it's not enabled. If hi.IngressEnabled is true, control knows that
+	// DNS records are needed, so we can save bandwidth and not send
+	// WireIngress.
+	hi.WireIngress = b.shouldWireInactiveIngressLocked()
 	hi.AppConnector.Set(prefs.AppConnector().Advertise)
 }
 
@@ -6229,8 +6484,6 @@ func (b *LocalBackend) setTCPPortsInterceptedFromNetmapAndPrefsLocked(prefs ipn.
 
 // updateIngressLocked updates the hostinfo.WireIngress and hostinfo.IngressEnabled fields and kicks off a Hostinfo
 // update if the values have changed.
-// TODO(irbekrm): once control knows that if hostinfo.IngressEnabled is true, then wireIngress can be considered true,
-// we can stop sending hostinfo.WireIngress in that case.
 //
 // b.mu must be held.
 func (b *LocalBackend) updateIngressLocked() {
@@ -6238,16 +6491,16 @@ func (b *LocalBackend) updateIngressLocked() {
 		return
 	}
 	hostInfoChanged := false
-	if wire := b.wantIngressLocked(); b.hostinfo.WireIngress != wire {
-		b.logf("Hostinfo.WireIngress changed to %v", wire)
-		b.hostinfo.WireIngress = wire
-		hostInfoChanged = true
-	}
 	if ie := b.hasIngressEnabledLocked(); b.hostinfo.IngressEnabled != ie {
 		b.logf("Hostinfo.IngressEnabled changed to %v", ie)
 		b.hostinfo.IngressEnabled = ie
 		hostInfoChanged = true
 	}
+	if wire := b.shouldWireInactiveIngressLocked(); b.hostinfo.WireIngress != wire {
+		b.logf("Hostinfo.WireIngress changed to %v", wire)
+		b.hostinfo.WireIngress = wire
+		hostInfoChanged = true
+	}
 	// Kick off a Hostinfo update to control if ingress status has changed.
 	if hostInfoChanged {
 		b.goTracker.Go(b.doSetHostinfoFilterServices)
@@ -6455,6 +6708,41 @@ func (b *LocalBackend) FileTargets() ([]*apitype.FileTarget, error) {
 	return ret, nil
 }
 
+func (b *LocalBackend) taildropTargetStatus(p tailcfg.NodeView) ipnstate.TaildropTargetStatus {
+	if b.netMap == nil || b.state != ipn.Running {
+		return ipnstate.TaildropTargetIpnStateNotRunning
+	}
+	if b.netMap == nil {
+		return ipnstate.TaildropTargetNoNetmapAvailable
+	}
+	if !b.capFileSharing {
+		return ipnstate.TaildropTargetMissingCap
+	}
+
+	if !p.Online().Get() {
+		return ipnstate.TaildropTargetOffline
+	}
+
+	if !p.Valid() {
+		return ipnstate.TaildropTargetNoPeerInfo
+	}
+	if b.netMap.User() != p.User() {
+		// Different user must have the explicit file sharing target capability
+		if p.Addresses().Len() == 0 ||
+			!b.peerHasCapLocked(p.Addresses().At(0).Addr(), tailcfg.PeerCapabilityFileSharingTarget) {
+			return ipnstate.TaildropTargetOwnedByOtherUser
+		}
+	}
+
+	if p.Hostinfo().OS() == "tvOS" {
+		return ipnstate.TaildropTargetUnsupportedOS
+	}
+	if peerAPIBase(b.netMap, p) == "" {
+		return ipnstate.TaildropTargetNoPeerAPI
+	}
+	return ipnstate.TaildropTargetAvailable
+}
+
 // peerIsTaildropTargetLocked reports whether p is a valid Taildrop file
 // recipient from this node according to its ownership and the capabilities in
 // the netmap.
@@ -7190,9 +7478,9 @@ func (b *LocalBackend) resetForProfileChangeLockedOnEntry(unlock unlockOnce) err
 		// Needs to happen without b.mu held.
 		defer prevCC.Shutdown()
 	}
-	if err := b.initTKALocked(); err != nil {
-		return err
-	}
+	// TKA errors should not prevent resetting the backend state.
+	// However, we should still return the error to the caller.
+	tkaErr := b.initTKALocked()
 	b.lastServeConfJSON = mem.B(nil)
 	b.serveConfig = ipn.ServeConfigView{}
 	b.lastSuggestedExitNode = ""
@@ -7201,6 +7489,9 @@ func (b *LocalBackend) resetForProfileChangeLockedOnEntry(unlock unlockOnce) err
 	b.setAtomicValuesFromPrefsLocked(b.pm.CurrentPrefs())
 	b.enterStateLockedOnEntry(ipn.NoState, unlock) // Reset state; releases b.mu
 	b.health.SetLocalLogConfigHealth(nil)
+	if tkaErr != nil {
+		return tkaErr
+	}
 	return b.Start(ipn.Options{})
 }
 

ipn/ipnlocal/local_test.go

@@ -5084,7 +5084,7 @@ func TestUpdateIngressLocked(t *testing.T) {
 				},
 			},
 			wantIngress:       true,
-			wantWireIngress:   true,
+			wantWireIngress:   false, // implied by wantIngress
 			wantControlUpdate: true,
 		},
 		{
@@ -5111,7 +5111,6 @@ func TestUpdateIngressLocked(t *testing.T) {
 			name: "funnel_enabled_no_change",
 			hi: &tailcfg.Hostinfo{
 				IngressEnabled: true,
-				WireIngress:    true,
 			},
 			sc: &ipn.ServeConfig{
 				AllowFunnel: map[ipn.HostPort]bool{
@@ -5119,7 +5118,7 @@ func TestUpdateIngressLocked(t *testing.T) {
 				},
 			},
 			wantIngress:     true,
-			wantWireIngress: true,
+			wantWireIngress: false, // implied by wantIngress
 		},
 		{
 			name: "funnel_disabled_no_change",
@@ -5137,7 +5136,6 @@ func TestUpdateIngressLocked(t *testing.T) {
 			name: "funnel_changes_to_disabled",
 			hi: &tailcfg.Hostinfo{
 				IngressEnabled: true,
-				WireIngress:    true,
 			},
 			sc: &ipn.ServeConfig{
 				AllowFunnel: map[ipn.HostPort]bool{
@@ -5157,8 +5155,8 @@ func TestUpdateIngressLocked(t *testing.T) {
 					"tailnet.xyz:443": true,
 				},
 			},
-			wantWireIngress:   true,
 			wantIngress:       true,
+			wantWireIngress:   false, // implied by wantIngress
 			wantControlUpdate: true,
 		},
 	}

ipn/ipnlocal/profiles.go

@@ -91,24 +91,25 @@ func (pm *profileManager) SetCurrentUserID(uid ipn.WindowsUserID) {
 // profile for the user and switches to it, unless the current profile
 // is already a new, empty profile owned by the user.
 //
-// It reports whether the call resulted in a profile switch.
-func (pm *profileManager) SetCurrentUserAndProfile(uid ipn.WindowsUserID, profileID ipn.ProfileID) (changed bool) {
+// It returns the current profile and whether the call resulted
+// in a profile switch.
+func (pm *profileManager) SetCurrentUserAndProfile(uid ipn.WindowsUserID, profileID ipn.ProfileID) (cp ipn.LoginProfileView, changed bool) {
 	pm.currentUserID = uid
 
 	if profileID == "" {
 		if pm.currentProfile.ID() == "" && pm.currentProfile.LocalUserID() == uid {
-			return false
+			return pm.currentProfile, false
 		}
 		pm.NewProfileForUser(uid)
-		return true
+		return pm.currentProfile, true
 	}
 
 	if profile, err := pm.ProfileByID(profileID); err == nil {
 		if pm.CurrentProfile().ID() == profileID {
-			return false
+			return pm.currentProfile, false
 		}
 		if err := pm.SwitchProfile(profile.ID()); err == nil {
-			return true
+			return pm.currentProfile, true
 		}
 	}
 
@@ -116,7 +117,7 @@ func (pm *profileManager) SetCurrentUserAndProfile(uid ipn.WindowsUserID, profil
 		pm.logf("%q's default profile cannot be used; creating a new one: %v", uid, err)
 		pm.NewProfile()
 	}
-	return true
+	return pm.currentProfile, true
 }
 
 // DefaultUserProfileID returns [ipn.ProfileID] of the default (last used) profile for the specified user,

ipn/ipnserver/actor.go

@@ -32,6 +32,7 @@ type actor struct {
 	ci   *ipnauth.ConnIdentity
 
 	clientID ipnauth.ClientID
+	userID   ipn.WindowsUserID // cached Windows user ID of the connected client process.
 	// accessOverrideReason specifies the reason for overriding certain access restrictions,
 	// such as permitting a user to disconnect when the always-on mode is enabled,
 	// provided that such justification is allowed by the policy.
@@ -59,7 +60,14 @@ func newActor(logf logger.Logf, c net.Conn) (*actor, error) {
 		// connectivity on domain-joined devices and/or be slow.
 		clientID = ipnauth.ClientIDFrom(pid)
 	}
-	return &actor{logf: logf, ci: ci, clientID: clientID, isLocalSystem: connIsLocalSystem(ci)}, nil
+	return &actor{
+			logf:          logf,
+			ci:            ci,
+			clientID:      clientID,
+			userID:        ci.WindowsUserID(),
+			isLocalSystem: connIsLocalSystem(ci),
+		},
+		nil
 }
 
 // actorWithAccessOverride returns a new actor that carries the specified
@@ -73,6 +81,7 @@ func actorWithAccessOverride(baseActor *actor, reason string) *actor {
 		logf:                 baseActor.logf,
 		ci:                   baseActor.ci,
 		clientID:             baseActor.clientID,
+		userID:               baseActor.userID,
 		accessOverrideReason: reason,
 		isLocalSystem:        baseActor.isLocalSystem,
 	}
@@ -106,7 +115,7 @@ func (a *actor) IsLocalAdmin(operatorUID string) bool {
 
 // UserID implements [ipnauth.Actor].
 func (a *actor) UserID() ipn.WindowsUserID {
-	return a.ci.WindowsUserID()
+	return a.userID
 }
 
 func (a *actor) pid() int {

ipn/ipnstate/ipnstate.go

@@ -270,6 +270,12 @@ type PeerStatus struct {
 	// PeerAPIURL are the URLs of the node's PeerAPI servers.
 	PeerAPIURL []string
 
+	// TaildropTargetStatus represents the node's eligibility to have files shared to it.
+	TaildropTarget TaildropTargetStatus
+
+	// Reason why this peer cannot receive files. Empty if CanReceiveFiles=true
+	NoFileSharingReason string
+
 	// Capabilities are capabilities that the node has.
 	// They're free-form strings, but should be in the form of URLs/URIs
 	// such as:
@@ -318,6 +324,21 @@ type PeerStatus struct {
 	Location *tailcfg.Location `json:",omitempty"`
 }
 
+type TaildropTargetStatus int
+
+const (
+	TaildropTargetUnknown TaildropTargetStatus = iota
+	TaildropTargetAvailable
+	TaildropTargetNoNetmapAvailable
+	TaildropTargetIpnStateNotRunning
+	TaildropTargetMissingCap
+	TaildropTargetOffline
+	TaildropTargetNoPeerInfo
+	TaildropTargetUnsupportedOS
+	TaildropTargetNoPeerAPI
+	TaildropTargetOwnedByOtherUser
+)
+
 // HasCap reports whether ps has the given capability.
 func (ps *PeerStatus) HasCap(cap tailcfg.NodeCapability) bool {
 	return ps.CapMap.Contains(cap)

maths/ewma.go

@@ -0,0 +1,72 @@
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
+
+// Package maths contains additional mathematical functions or structures not
+// found in the standard library.
+package maths
+
+import (
+	"math"
+	"time"
+)
+
+// EWMA is an exponentially weighted moving average supporting updates at
+// irregular intervals with at most nanosecond resolution.
+// The zero value will compute a half-life of 1 second.
+// It is not safe for concurrent use.
+// TODO(raggi): de-duplicate with tstime/rate.Value, which has a more complex
+// and synchronized interface and does not provide direct access to the stable
+// value.
+type EWMA struct {
+	value    float64 // current value of the average
+	lastTime int64   // time of last update in unix nanos
+	halfLife float64 // half-life in seconds
+}
+
+// NewEWMA creates a new EWMA with the specified half-life. If halfLifeSeconds
+// is 0, it defaults to 1.
+func NewEWMA(halfLifeSeconds float64) *EWMA {
+	return &EWMA{
+		halfLife: halfLifeSeconds,
+	}
+}
+
+// Update adds a new sample to the average. If t is zero or precedes the last
+// update, the update is ignored.
+func (e *EWMA) Update(value float64, t time.Time) {
+	if t.IsZero() {
+		return
+	}
+	hl := e.halfLife
+	if hl == 0 {
+		hl = 1
+	}
+	tn := t.UnixNano()
+	if e.lastTime == 0 {
+		e.value = value
+		e.lastTime = tn
+		return
+	}
+
+	dt := (time.Duration(tn-e.lastTime) * time.Nanosecond).Seconds()
+	if dt < 0 {
+		// drop out of order updates
+		return
+	}
+
+	// decay = 2^(-dt/halfLife)
+	decay := math.Exp2(-dt / hl)
+	e.value = e.value*decay + value*(1-decay)
+	e.lastTime = tn
+}
+
+// Get returns the current value of the average
+func (e *EWMA) Get() float64 {
+	return e.value
+}
+
+// Reset clears the EWMA to its initial state
+func (e *EWMA) Reset() {
+	e.value = 0
+	e.lastTime = 0
+}

maths/ewma_test.go

@@ -0,0 +1,178 @@
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
+
+package maths
+
+import (
+	"slices"
+	"testing"
+	"time"
+)
+
+// some real world latency samples.
+var (
+	latencyHistory1 = []int{
+		14, 12, 15, 6, 19, 12, 13, 13, 13, 16, 17, 11, 17, 11, 14, 15, 14, 15,
+		16, 16, 17, 14, 12, 16, 18, 14, 14, 11, 15, 15, 25, 11, 15, 14, 12, 15,
+		13, 12, 13, 15, 11, 13, 15, 14, 14, 15, 12, 15, 18, 12, 15, 22, 12, 13,
+		10, 14, 16, 15, 16, 11, 14, 17, 18, 20, 16, 11, 16, 14, 5, 15, 17, 12,
+		15, 11, 15, 20, 12, 17, 12, 17, 15, 12, 12, 11, 14, 15, 11, 20, 14, 13,
+		11, 12, 13, 13, 11, 13, 11, 15, 13, 13, 14, 12, 11, 12, 12, 14, 11, 13,
+		12, 12, 12, 19, 14, 13, 13, 14, 11, 12, 10, 11, 15, 12, 14, 11, 11, 14,
+		14, 12, 12, 11, 14, 12, 11, 12, 14, 11, 12, 15, 12, 14, 12, 12, 21, 16,
+		21, 12, 16, 9, 11, 16, 14, 13, 14, 12, 13, 16,
+	}
+	latencyHistory2 = []int{
+		18, 20, 21, 21, 20, 23, 18, 18, 20, 21, 20, 19, 22, 18, 20, 20, 19, 21,
+		21, 22, 22, 19, 18, 22, 22, 19, 20, 17, 16, 11, 25, 16, 18, 21, 17, 22,
+		19, 18, 22, 21, 20, 18, 22, 17, 17, 20, 19, 10, 19, 16, 19, 25, 17, 18,
+		15, 20, 21, 20, 23, 22, 22, 22, 19, 22, 22, 17, 22, 20, 20, 19, 21, 22,
+		20, 19, 17, 22, 16, 16, 20, 22, 17, 19, 21, 16, 20, 22, 19, 21, 20, 19,
+		13, 14, 23, 19, 16, 10, 19, 15, 15, 17, 16, 18, 14, 16, 18, 22, 20, 18,
+		18, 21, 15, 19, 18, 19, 18, 20, 17, 19, 21, 19, 20, 19, 20, 20, 17, 14,
+		17, 17, 18, 21, 20, 18, 18, 17, 16, 17, 17, 20, 22, 19, 20, 21, 21, 20,
+		21, 24, 20, 18, 12, 17, 18, 17, 19, 19, 19,
+	}
+)
+
+func TestEWMALatencyHistory(t *testing.T) {
+	type result struct {
+		t time.Time
+		v float64
+		s int
+	}
+
+	for _, latencyHistory := range [][]int{latencyHistory1, latencyHistory2} {
+		startTime := time.Date(2025, 1, 1, 12, 0, 0, 0, time.UTC)
+		halfLife := 30.0
+
+		ewma := NewEWMA(halfLife)
+
+		var results []result
+		sum := 0.0
+		for i, latency := range latencyHistory {
+			t := startTime.Add(time.Duration(i) * time.Second)
+			ewma.Update(float64(latency), t)
+			sum += float64(latency)
+
+			results = append(results, result{t, ewma.Get(), latency})
+		}
+		mean := sum / float64(len(latencyHistory))
+		min := float64(slices.Min(latencyHistory))
+		max := float64(slices.Max(latencyHistory))
+
+		t.Logf("EWMA Latency History (half-life: %.1f seconds):", halfLife)
+		t.Logf("Mean latency: %.2f ms", mean)
+		t.Logf("Range: [%.1f, %.1f]", min, max)
+
+		t.Log("Samples: ")
+		sparkline := []rune("▁▂▃▄▅▆▇█")
+		var sampleLine []rune
+		for _, r := range results {
+			idx := int(((float64(r.s) - min) / (max - min)) * float64(len(sparkline)-1))
+			if idx >= len(sparkline) {
+				idx = len(sparkline) - 1
+			}
+			sampleLine = append(sampleLine, sparkline[idx])
+		}
+		t.Log(string(sampleLine))
+
+		t.Log("EWMA:    ")
+		var ewmaLine []rune
+		for _, r := range results {
+			idx := int(((r.v - min) / (max - min)) * float64(len(sparkline)-1))
+			if idx >= len(sparkline) {
+				idx = len(sparkline) - 1
+			}
+			ewmaLine = append(ewmaLine, sparkline[idx])
+		}
+		t.Log(string(ewmaLine))
+		t.Log("")
+
+		t.Logf("Time       | Sample | Value  | Value - Sample")
+		t.Logf("")
+
+		for _, result := range results {
+			t.Logf("%10s | % 6d | % 5.2f | % 5.2f", result.t.Format("15:04:05"), result.s, result.v, result.v-float64(result.s))
+		}
+
+		// check that all results are greater than the min, and less than the max of the input,
+		// and they're all close to the mean.
+		for _, result := range results {
+			if result.v < float64(min) || result.v > float64(max) {
+				t.Errorf("result %f out of range [%f, %f]", result.v, min, max)
+			}
+
+			if result.v < mean*0.9 || result.v > mean*1.1 {
+				t.Errorf("result %f not close to mean %f", result.v, mean)
+			}
+		}
+	}
+}
+
+func TestHalfLife(t *testing.T) {
+	start := time.Date(2025, 1, 1, 12, 0, 0, 0, time.UTC)
+
+	ewma := NewEWMA(30.0)
+	ewma.Update(10, start)
+	ewma.Update(0, start.Add(30*time.Second))
+
+	if ewma.Get() != 5 {
+		t.Errorf("expected 5, got %f", ewma.Get())
+	}
+
+	ewma.Update(10, start.Add(60*time.Second))
+	if ewma.Get() != 7.5 {
+		t.Errorf("expected 7.5, got %f", ewma.Get())
+	}
+
+	ewma.Update(10, start.Add(90*time.Second))
+	if ewma.Get() != 8.75 {
+		t.Errorf("expected 8.75, got %f", ewma.Get())
+	}
+}
+
+func TestZeroValue(t *testing.T) {
+	start := time.Date(2025, 1, 1, 12, 0, 0, 0, time.UTC)
+
+	var ewma EWMA
+	ewma.Update(10, start)
+	ewma.Update(0, start.Add(time.Second))
+
+	if ewma.Get() != 5 {
+		t.Errorf("expected 5, got %f", ewma.Get())
+	}
+
+	ewma.Update(10, start.Add(2*time.Second))
+	if ewma.Get() != 7.5 {
+		t.Errorf("expected 7.5, got %f", ewma.Get())
+	}
+
+	ewma.Update(10, start.Add(3*time.Second))
+	if ewma.Get() != 8.75 {
+		t.Errorf("expected 8.75, got %f", ewma.Get())
+	}
+}
+
+func TestReset(t *testing.T) {
+	start := time.Date(2025, 1, 1, 12, 0, 0, 0, time.UTC)
+
+	ewma := NewEWMA(30.0)
+	ewma.Update(10, start)
+	ewma.Update(0, start.Add(30*time.Second))
+
+	if ewma.Get() != 5 {
+		t.Errorf("expected 5, got %f", ewma.Get())
+	}
+
+	ewma.Reset()
+
+	if ewma.Get() != 0 {
+		t.Errorf("expected 0, got %f", ewma.Get())
+	}
+
+	ewma.Update(10, start.Add(90*time.Second))
+	if ewma.Get() != 10 {
+		t.Errorf("expected 10, got %f", ewma.Get())
+	}
+}

net/ktimeout/ktimeout_linux_test.go

@@ -4,17 +4,22 @@
 package ktimeout
 
 import (
+	"context"
 	"net"
 	"testing"
 	"time"
 
-	"golang.org/x/net/nettest"
 	"golang.org/x/sys/unix"
 	"tailscale.com/util/must"
 )
 
 func TestSetUserTimeout(t *testing.T) {
-	l := must.Get(nettest.NewLocalListener("tcp"))
+	lc := net.ListenConfig{}
+	// As of 2025-02-19, MPTCP does not support TCP_USER_TIMEOUT socket option
+	// set in ktimeout.UserTimeout above.
+	lc.SetMultipathTCP(false)
+
+	l := must.Get(lc.Listen(context.Background(), "tcp", "localhost:0"))
 	defer l.Close()
 
 	var err error

net/netcheck/netcheck.go

@@ -172,25 +172,14 @@ func (r *Report) Clone() *Report {
 		return nil
 	}
 	r2 := *r
-	r2.RegionLatency = cloneDurationMap(r2.RegionLatency)
-	r2.RegionV4Latency = cloneDurationMap(r2.RegionV4Latency)
-	r2.RegionV6Latency = cloneDurationMap(r2.RegionV6Latency)
+	r2.RegionLatency = maps.Clone(r2.RegionLatency)
+	r2.RegionV4Latency = maps.Clone(r2.RegionV4Latency)
+	r2.RegionV6Latency = maps.Clone(r2.RegionV6Latency)
 	r2.GlobalV4Counters = maps.Clone(r2.GlobalV4Counters)
 	r2.GlobalV6Counters = maps.Clone(r2.GlobalV6Counters)
 	return &r2
 }
 
-func cloneDurationMap(m map[int]time.Duration) map[int]time.Duration {
-	if m == nil {
-		return nil
-	}
-	m2 := make(map[int]time.Duration, len(m))
-	for k, v := range m {
-		m2[k] = v
-	}
-	return m2
-}
-
 // Client generates Reports describing the result of both passive and active
 // network configuration probing. It provides two different modes of report, a
 // full report (see MakeNextReportFull) and a more lightweight incremental

scripts/installer.sh

@@ -7,6 +7,14 @@
 
 set -eu
 
+# Ensure that this script runs with the default umask for Linux. In practice,
+# this means that files created by this script (such as keyring files) will be
+# created with 644 permissions. This ensures that keyrings and other files
+# created by this script are readable by installers on systems where the
+# umask is set to a more restrictive value.
+# See https://github.com/tailscale/tailscale/issues/15133
+umask 022
+
 # All the code is wrapped in a main function that gets called at the
 # bottom of the file, so that a truncated partial download doesn't end
 # up executing half a script.
@@ -186,6 +194,12 @@ main() {
 					VERSION="$DEBIAN_CODENAME"
 				fi
 				;;
+			sparky)
+				OS="debian"
+				PACKAGETYPE="apt"
+				VERSION="$DEBIAN_CODENAME"
+				APT_KEY_TYPE="keyring"
+				;;
 			centos)
 				OS="$ID"
 				VERSION="$VERSION_ID"

ssh/tailssh/tailssh.go

@@ -51,6 +51,11 @@ var (
 	sshDisableSFTP       = envknob.RegisterBool("TS_SSH_DISABLE_SFTP")
 	sshDisableForwarding = envknob.RegisterBool("TS_SSH_DISABLE_FORWARDING")
 	sshDisablePTY        = envknob.RegisterBool("TS_SSH_DISABLE_PTY")
+
+	// errTerminal is an empty gossh.PartialSuccessError (with no 'Next'
+	// authentication methods that may proceed), which results in the SSH
+	// server immediately disconnecting the client.
+	errTerminal = &gossh.PartialSuccessError{}
 )
 
 const (
@@ -230,8 +235,8 @@ type conn struct {
 	finalAction *tailcfg.SSHAction // set by clientAuth
 
 	info         *sshConnInfo // set by setInfo
-	localUser    *userMeta    // set by doPolicyAuth
-	userGroupIDs []string     // set by doPolicyAuth
+	localUser    *userMeta    // set by clientAuth
+	userGroupIDs []string     // set by clientAuth
 	acceptEnv    []string
 
 	// mu protects the following fields.
@@ -255,46 +260,73 @@ func (c *conn) vlogf(format string, args ...any) {
 }
 
 // errDenied is returned by auth callbacks when a connection is denied by the
-// policy. It returns a gossh.BannerError to make sure the message gets
-// displayed as an auth banner.
-func errDenied(message string) error {
+// policy. It writes the message to an auth banner and then returns an empty
+// gossh.PartialSuccessError in order to stop processing authentication
+// attempts and immediately disconnect the client.
+func (c *conn) errDenied(message string) error {
 	if message == "" {
 		message = "tailscale: access denied"
 	}
-	return &gossh.BannerError{
-		Message: message,
+	if err := c.spac.SendAuthBanner(message); err != nil {
+		c.logf("failed to send auth banner: %s", err)
 	}
+	return errTerminal
 }
 
-// bannerError creates a gossh.BannerError that will result in the given
-// message being displayed to the client. If err != nil, this also logs
-// message:error. The contents of err is not leaked to clients in the banner.
-func (c *conn) bannerError(message string, err error) error {
+// errBanner writes the given message to an auth banner and then returns an
+// empty gossh.PartialSuccessError in order to stop processing authentication
+// attempts and immediately disconnect the client. The contents of err is not
+// leaked in the auth banner, but it is logged to the server's log.
+func (c *conn) errBanner(message string, err error) error {
 	if err != nil {
 		c.logf("%s: %s", message, err)
 	}
-	return &gossh.BannerError{
-		Err:     err,
-		Message: fmt.Sprintf("tailscale: %s", message),
+	if err := c.spac.SendAuthBanner("tailscale: " + message); err != nil {
+		c.logf("failed to send auth banner: %s", err)
 	}
+	return errTerminal
+}
+
+// errUnexpected is returned by auth callbacks that encounter an unexpected
+// error, such as being unable to send an auth banner. It sends an empty
+// gossh.PartialSuccessError to tell gossh.Server to stop processing
+// authentication attempts and instead disconnect immediately.
+func (c *conn) errUnexpected(err error) error {
+	c.logf("terminal error: %s", err)
+	return errTerminal
 }
 
 // clientAuth is responsible for performing client authentication.
 //
 // If policy evaluation fails, it returns an error.
-// If access is denied, it returns an error.
-func (c *conn) clientAuth(cm gossh.ConnMetadata) (*gossh.Permissions, error) {
+// If access is denied, it returns an error. This must always be an empty
+// gossh.PartialSuccessError to prevent further authentication methods from
+// being tried.
+func (c *conn) clientAuth(cm gossh.ConnMetadata) (perms *gossh.Permissions, retErr error) {
+	defer func() {
+		if pse, ok := retErr.(*gossh.PartialSuccessError); ok {
+			if pse.Next.GSSAPIWithMICConfig != nil ||
+				pse.Next.KeyboardInteractiveCallback != nil ||
+				pse.Next.PasswordCallback != nil ||
+				pse.Next.PublicKeyCallback != nil {
+				panic("clientAuth attempted to return a non-empty PartialSuccessError")
+			}
+		} else if retErr != nil {
+			panic(fmt.Sprintf("clientAuth attempted to return a non-PartialSuccessError error of type: %t", retErr))
+		}
+	}()
+
 	if c.insecureSkipTailscaleAuth {
 		return &gossh.Permissions{}, nil
 	}
 
 	if err := c.setInfo(cm); err != nil {
-		return nil, c.bannerError("failed to get connection info", err)
+		return nil, c.errBanner("failed to get connection info", err)
 	}
 
 	action, localUser, acceptEnv, err := c.evaluatePolicy()
 	if err != nil {
-		return nil, c.bannerError("failed to evaluate SSH policy", err)
+		return nil, c.errBanner("failed to evaluate SSH policy", err)
 	}
 
 	c.action0 = action
@@ -304,11 +336,11 @@ func (c *conn) clientAuth(cm gossh.ConnMetadata) (*gossh.Permissions, error) {
 		// hold and delegate URL (if necessary).
 		lu, err := userLookup(localUser)
 		if err != nil {
-			return nil, c.bannerError(fmt.Sprintf("failed to look up local user %q ", localUser), err)
+			return nil, c.errBanner(fmt.Sprintf("failed to look up local user %q ", localUser), err)
 		}
 		gids, err := lu.GroupIds()
 		if err != nil {
-			return nil, c.bannerError("failed to look up local user's group IDs", err)
+			return nil, c.errBanner("failed to look up local user's group IDs", err)
 		}
 		c.userGroupIDs = gids
 		c.localUser = lu
@@ -321,7 +353,7 @@ func (c *conn) clientAuth(cm gossh.ConnMetadata) (*gossh.Permissions, error) {
 			metricTerminalAccept.Add(1)
 			if action.Message != "" {
 				if err := c.spac.SendAuthBanner(action.Message); err != nil {
-					return nil, fmt.Errorf("error sending auth welcome message: %w", err)
+					return nil, c.errUnexpected(fmt.Errorf("error sending auth welcome message: %w", err))
 				}
 			}
 			c.finalAction = action
@@ -329,11 +361,11 @@ func (c *conn) clientAuth(cm gossh.ConnMetadata) (*gossh.Permissions, error) {
 		case action.Reject:
 			metricTerminalReject.Add(1)
 			c.finalAction = action
-			return nil, errDenied(action.Message)
+			return nil, c.errDenied(action.Message)
 		case action.HoldAndDelegate != "":
 			if action.Message != "" {
 				if err := c.spac.SendAuthBanner(action.Message); err != nil {
-					return nil, fmt.Errorf("error sending hold and delegate message: %w", err)
+					return nil, c.errUnexpected(fmt.Errorf("error sending hold and delegate message: %w", err))
 				}
 			}
 
@@ -349,11 +381,11 @@ func (c *conn) clientAuth(cm gossh.ConnMetadata) (*gossh.Permissions, error) {
 			action, err = c.fetchSSHAction(ctx, url)
 			if err != nil {
 				metricTerminalFetchError.Add(1)
-				return nil, c.bannerError("failed to fetch next SSH action", fmt.Errorf("fetch failed from %s: %w", url, err))
+				return nil, c.errBanner("failed to fetch next SSH action", fmt.Errorf("fetch failed from %s: %w", url, err))
 			}
 		default:
 			metricTerminalMalformed.Add(1)
-			return nil, c.bannerError("reached Action that had neither Accept, Reject, nor HoldAndDelegate", nil)
+			return nil, c.errBanner("reached Action that had neither Accept, Reject, nor HoldAndDelegate", nil)
 		}
 	}
 }
@@ -390,6 +422,20 @@ func (c *conn) ServerConfig(ctx ssh.Context) *gossh.ServerConfig {
 
 			return perms, nil
 		},
+		PasswordCallback: func(cm gossh.ConnMetadata, pword []byte) (*gossh.Permissions, error) {
+			// Some clients don't request 'none' authentication. Instead, they
+			// immediately supply a password. We humor them by accepting the
+			// password, but authenticate as usual, ignoring the actual value of
+			// the password.
+			return c.clientAuth(cm)
+		},
+		PublicKeyCallback: func(cm gossh.ConnMetadata, key gossh.PublicKey) (*gossh.Permissions, error) {
+			// Some clients don't request 'none' authentication. Instead, they
+			// immediately supply a public key. We humor them by accepting the
+			// key, but authenticate as usual, ignoring the actual content of
+			// the key.
+			return c.clientAuth(cm)
+		},
 	}
 }
 
@@ -400,7 +446,7 @@ func (srv *server) newConn() (*conn, error) {
 		// Stop accepting new connections.
 		// Connections in the auth phase are handled in handleConnPostSSHAuth.
 		// Existing sessions are terminated by Shutdown.
-		return nil, errDenied("tailscale: server is shutting down")
+		return nil, errors.New("server is shutting down")
 	}
 	srv.mu.Unlock()
 	c := &conn{srv: srv}

ssh/tailssh/tailssh_integration_test.go

@@ -2,7 +2,6 @@
 // SPDX-License-Identifier: BSD-3-Clause
 
 //go:build integrationtest
-// +build integrationtest
 
 package tailssh
 
@@ -410,6 +409,48 @@ func TestSSHAgentForwarding(t *testing.T) {
 	}
 }
 
+// TestIntegrationParamiko attempts to connect to Tailscale SSH using the
+// paramiko Python library. This library does not request 'none' auth. This
+// test ensures that Tailscale SSH can correctly handle clients that don't
+// request 'none' auth and instead immediately authenticate with a public key
+// or password.
+func TestIntegrationParamiko(t *testing.T) {
+	debugTest.Store(true)
+	t.Cleanup(func() {
+		debugTest.Store(false)
+	})
+
+	addr := testServer(t, "testuser", true, false)
+	host, port, err := net.SplitHostPort(addr)
+	if err != nil {
+		t.Fatalf("Failed to split addr %q: %s", addr, err)
+	}
+
+	out, err := exec.Command("python3", "-c", fmt.Sprintf(`
+import paramiko.client as pm
+from paramiko.ecdsakey import ECDSAKey
+client = pm.SSHClient()
+client.set_missing_host_key_policy(pm.AutoAddPolicy)
+client.connect('%s', port=%s, username='testuser', pkey=ECDSAKey.generate(), allow_agent=False, look_for_keys=False)
+client.exec_command('pwd')
+`, host, port)).CombinedOutput()
+	if err != nil {
+		t.Fatalf("failed to connect with Paramiko using public key auth: %s\n%q", err, string(out))
+	}
+
+	out, err = exec.Command("python3", "-c", fmt.Sprintf(`
+import paramiko.client as pm
+from paramiko.ecdsakey import ECDSAKey
+client = pm.SSHClient()
+client.set_missing_host_key_policy(pm.AutoAddPolicy)
+client.connect('%s', port=%s, username='testuser', password='doesntmatter', allow_agent=False, look_for_keys=False)
+client.exec_command('pwd')
+`, host, port)).CombinedOutput()
+	if err != nil {
+		t.Fatalf("failed to connect with Paramiko using password auth: %s\n%q", err, string(out))
+	}
+}
+
 func fallbackToSUAvailable() bool {
 	if runtime.GOOS != "linux" {
 		return false

ssh/tailssh/tailssh_test.go

@@ -8,12 +8,15 @@ package tailssh
 import (
 	"bytes"
 	"context"
+	"crypto/ecdsa"
 	"crypto/ed25519"
+	"crypto/elliptic"
 	"crypto/rand"
 	"encoding/json"
 	"errors"
 	"fmt"
 	"io"
+	"log"
 	"net"
 	"net/http"
 	"net/http/httptest"
@@ -41,7 +44,7 @@ import (
 	"tailscale.com/sessionrecording"
 	"tailscale.com/tailcfg"
 	"tailscale.com/tempfork/gliderlabs/ssh"
-	sshtest "tailscale.com/tempfork/sshtest/ssh"
+	testssh "tailscale.com/tempfork/sshtest/ssh"
 	"tailscale.com/tsd"
 	"tailscale.com/tstest"
 	"tailscale.com/types/key"
@@ -56,8 +59,6 @@ import (
 	"tailscale.com/wgengine"
 )
 
-type _ = sshtest.Client // TODO(bradfitz,percy): sshtest; delete this line
-
 func TestMatchRule(t *testing.T) {
 	someAction := new(tailcfg.SSHAction)
 	tests := []struct {
@@ -510,9 +511,9 @@ func TestSSHRecordingCancelsSessionsOnUploadFailure(t *testing.T) {
 	defer s.Shutdown()
 
 	const sshUser = "alice"
-	cfg := &gossh.ClientConfig{
+	cfg := &testssh.ClientConfig{
 		User:            sshUser,
-		HostKeyCallback: gossh.InsecureIgnoreHostKey(),
+		HostKeyCallback: testssh.InsecureIgnoreHostKey(),
 	}
 
 	tests := []struct {
@@ -559,12 +560,12 @@ func TestSSHRecordingCancelsSessionsOnUploadFailure(t *testing.T) {
 			wg.Add(1)
 			go func() {
 				defer wg.Done()
-				c, chans, reqs, err := gossh.NewClientConn(sc, sc.RemoteAddr().String(), cfg)
+				c, chans, reqs, err := testssh.NewClientConn(sc, sc.RemoteAddr().String(), cfg)
 				if err != nil {
 					t.Errorf("client: %v", err)
 					return
 				}
-				client := gossh.NewClient(c, chans, reqs)
+				client := testssh.NewClient(c, chans, reqs)
 				defer client.Close()
 				session, err := client.NewSession()
 				if err != nil {
@@ -645,21 +646,21 @@ func TestMultipleRecorders(t *testing.T) {
 	sc, dc := memnet.NewTCPConn(src, dst, 1024)
 
 	const sshUser = "alice"
-	cfg := &gossh.ClientConfig{
+	cfg := &testssh.ClientConfig{
 		User:            sshUser,
-		HostKeyCallback: gossh.InsecureIgnoreHostKey(),
+		HostKeyCallback: testssh.InsecureIgnoreHostKey(),
 	}
 
 	var wg sync.WaitGroup
 	wg.Add(1)
 	go func() {
 		defer wg.Done()
-		c, chans, reqs, err := gossh.NewClientConn(sc, sc.RemoteAddr().String(), cfg)
+		c, chans, reqs, err := testssh.NewClientConn(sc, sc.RemoteAddr().String(), cfg)
 		if err != nil {
 			t.Errorf("client: %v", err)
 			return
 		}
-		client := gossh.NewClient(c, chans, reqs)
+		client := testssh.NewClient(c, chans, reqs)
 		defer client.Close()
 		session, err := client.NewSession()
 		if err != nil {
@@ -736,21 +737,21 @@ func TestSSHRecordingNonInteractive(t *testing.T) {
 	sc, dc := memnet.NewTCPConn(src, dst, 1024)
 
 	const sshUser = "alice"
-	cfg := &gossh.ClientConfig{
+	cfg := &testssh.ClientConfig{
 		User:            sshUser,
-		HostKeyCallback: gossh.InsecureIgnoreHostKey(),
+		HostKeyCallback: testssh.InsecureIgnoreHostKey(),
 	}
 
 	var wg sync.WaitGroup
 	wg.Add(1)
 	go func() {
 		defer wg.Done()
-		c, chans, reqs, err := gossh.NewClientConn(sc, sc.RemoteAddr().String(), cfg)
+		c, chans, reqs, err := testssh.NewClientConn(sc, sc.RemoteAddr().String(), cfg)
 		if err != nil {
 			t.Errorf("client: %v", err)
 			return
 		}
-		client := gossh.NewClient(c, chans, reqs)
+		client := testssh.NewClient(c, chans, reqs)
 		defer client.Close()
 		session, err := client.NewSession()
 		if err != nil {
@@ -886,80 +887,151 @@ func TestSSHAuthFlow(t *testing.T) {
 		},
 	}
 	s := &server{
-		logf: logger.Discard,
+		logf: log.Printf,
 	}
 	defer s.Shutdown()
 	src, dst := must.Get(netip.ParseAddrPort("100.100.100.101:2231")), must.Get(netip.ParseAddrPort("100.100.100.102:22"))
 	for _, tc := range tests {
-		t.Run(tc.name, func(t *testing.T) {
-			sc, dc := memnet.NewTCPConn(src, dst, 1024)
-			s.lb = tc.state
-			sshUser := "alice"
-			if tc.sshUser != "" {
-				sshUser = tc.sshUser
-			}
-			var passwordUsed atomic.Bool
-			cfg := &gossh.ClientConfig{
-				User:            sshUser,
-				HostKeyCallback: gossh.InsecureIgnoreHostKey(),
-				Auth: []gossh.AuthMethod{
-					gossh.PasswordCallback(func() (secret string, err error) {
-						if !tc.usesPassword {
-							t.Error("unexpected use of PasswordCallback")
-							return "", errors.New("unexpected use of PasswordCallback")
-						}
+		for _, authMethods := range [][]string{nil, {"publickey", "password"}, {"password", "publickey"}} {
+			t.Run(fmt.Sprintf("%s-skip-none-auth-%v", tc.name, strings.Join(authMethods, "-then-")), func(t *testing.T) {
+				sc, dc := memnet.NewTCPConn(src, dst, 1024)
+				s.lb = tc.state
+				sshUser := "alice"
+				if tc.sshUser != "" {
+					sshUser = tc.sshUser
+				}
+
+				wantBanners := slices.Clone(tc.wantBanners)
+				noneAuthEnabled := len(authMethods) == 0
+
+				var publicKeyUsed atomic.Bool
+				var passwordUsed atomic.Bool
+				var methods []testssh.AuthMethod
+
+				for _, authMethod := range authMethods {
+					switch authMethod {
+					case "publickey":
+						methods = append(methods,
+							testssh.PublicKeysCallback(func() (signers []testssh.Signer, err error) {
+								publicKeyUsed.Store(true)
+								key, err := ecdsa.GenerateKey(elliptic.P384(), rand.Reader)
+								if err != nil {
+									return nil, err
+								}
+								sig, err := testssh.NewSignerFromKey(key)
+								if err != nil {
+									return nil, err
+								}
+								return []testssh.Signer{sig}, nil
+							}))
+					case "password":
+						methods = append(methods, testssh.PasswordCallback(func() (secret string, err error) {
+							passwordUsed.Store(true)
+							return "any-pass", nil
+						}))
+					}
+				}
+
+				if noneAuthEnabled && tc.usesPassword {
+					methods = append(methods, testssh.PasswordCallback(func() (secret string, err error) {
 						passwordUsed.Store(true)
 						return "any-pass", nil
-					}),
-				},
-				BannerCallback: func(message string) error {
-					if len(tc.wantBanners) == 0 {
-						t.Errorf("unexpected banner: %q", message)
-					} else if message != tc.wantBanners[0] {
-						t.Errorf("banner = %q; want %q", message, tc.wantBanners[0])
-					} else {
-						t.Logf("banner = %q", message)
-						tc.wantBanners = tc.wantBanners[1:]
+					}))
+				}
+
+				cfg := &testssh.ClientConfig{
+					User:            sshUser,
+					HostKeyCallback: testssh.InsecureIgnoreHostKey(),
+					SkipNoneAuth:    !noneAuthEnabled,
+					Auth:            methods,
+					BannerCallback: func(message string) error {
+						if len(wantBanners) == 0 {
+							t.Errorf("unexpected banner: %q", message)
+						} else if message != wantBanners[0] {
+							t.Errorf("banner = %q; want %q", message, wantBanners[0])
+						} else {
+							t.Logf("banner = %q", message)
+							wantBanners = wantBanners[1:]
+						}
+						return nil
+					},
+				}
+
+				var wg sync.WaitGroup
+				wg.Add(1)
+				go func() {
+					defer wg.Done()
+					c, chans, reqs, err := testssh.NewClientConn(sc, sc.RemoteAddr().String(), cfg)
+					if err != nil {
+						if !tc.authErr {
+							t.Errorf("client: %v", err)
+						}
+						return
+					} else if tc.authErr {
+						c.Close()
+						t.Errorf("client: expected error, got nil")
+						return
 					}
-					return nil
-				},
-			}
-			var wg sync.WaitGroup
-			wg.Add(1)
-			go func() {
-				defer wg.Done()
-				c, chans, reqs, err := gossh.NewClientConn(sc, sc.RemoteAddr().String(), cfg)
-				if err != nil {
-					if !tc.authErr {
+					client := testssh.NewClient(c, chans, reqs)
+					defer client.Close()
+					session, err := client.NewSession()
+					if err != nil {
+						t.Errorf("client: %v", err)
+						return
+					}
+					defer session.Close()
+					_, err = session.CombinedOutput("echo Ran echo!")
+					if err != nil {
 						t.Errorf("client: %v", err)
 					}
-					return
-				} else if tc.authErr {
-					c.Close()
-					t.Errorf("client: expected error, got nil")
-					return
+				}()
+				if err := s.HandleSSHConn(dc); err != nil {
+					t.Errorf("unexpected error: %v", err)
 				}
-				client := gossh.NewClient(c, chans, reqs)
-				defer client.Close()
-				session, err := client.NewSession()
-				if err != nil {
-					t.Errorf("client: %v", err)
-					return
+				wg.Wait()
+				if len(wantBanners) > 0 {
+					t.Errorf("missing banners: %v", wantBanners)
 				}
-				defer session.Close()
-				_, err = session.CombinedOutput("echo Ran echo!")
-				if err != nil {
-					t.Errorf("client: %v", err)
+
+				// Check to see which callbacks were invoked.
+				//
+				// When `none` auth is enabled, the public key callback should
+				// never fire, and the password callback should only fire if
+				// authentication succeeded and the client was trying to force
+				// password authentication by connecting with the '-password'
+				// username suffix.
+				//
+				// When skipping `none` auth, the first callback should always
+				// fire, and the 2nd callback should fire only if
+				// authentication failed.
+				wantPublicKey := false
+				wantPassword := false
+				if noneAuthEnabled {
+					wantPassword = !tc.authErr && tc.usesPassword
+				} else {
+					for i, authMethod := range authMethods {
+						switch authMethod {
+						case "publickey":
+							wantPublicKey = i == 0 || tc.authErr
+						case "password":
+							wantPassword = i == 0 || tc.authErr
+						}
+					}
 				}
-			}()
-			if err := s.HandleSSHConn(dc); err != nil {
-				t.Errorf("unexpected error: %v", err)
-			}
-			wg.Wait()
-			if len(tc.wantBanners) > 0 {
-				t.Errorf("missing banners: %v", tc.wantBanners)
-			}
-		})
+
+				if wantPublicKey && !publicKeyUsed.Load() {
+					t.Error("public key should have been attempted")
+				} else if !wantPublicKey && publicKeyUsed.Load() {
+					t.Errorf("public key should not have been attempted")
+				}
+
+				if wantPassword && !passwordUsed.Load() {
+					t.Error("password should have been attempted")
+				} else if !wantPassword && passwordUsed.Load() {
+					t.Error("password should not have been attempted")
+				}
+			})
+		}
 	}
 }
 

ssh/tailssh/testcontainers/Dockerfile

@@ -3,9 +3,12 @@ FROM ${BASE}
 
 ARG BASE
 
-RUN echo "Install openssh, needed for scp."
-RUN if echo "$BASE" | grep "ubuntu:"; then apt-get update -y && apt-get install -y openssh-client; fi
-RUN if echo "$BASE" | grep "alpine:"; then apk add openssh; fi
+RUN echo "Install openssh, needed for scp. Also install python3"
+RUN if echo "$BASE" | grep "ubuntu:"; then apt-get update -y && apt-get install -y openssh-client python3 python3-pip; fi
+RUN if echo "$BASE" | grep "alpine:"; then apk add openssh python3 py3-pip; fi
+
+RUN echo "Install paramiko"
+RUN pip3 install paramiko==3.5.1 || pip3 install --break-system-packages paramiko==3.5.1
 
 # Note - on Ubuntu, we do not create the user's home directory, pam_mkhomedir will do that
 # for us, and we want to test that PAM gets triggered by Tailscale SSH.
@@ -33,6 +36,8 @@ RUN if echo "$BASE" | grep "ubuntu:"; then rm -Rf /home/testuser; fi
 RUN TAILSCALED_PATH=`pwd`tailscaled ./tailssh.test -test.v -test.run TestIntegrationSCP
 RUN if echo "$BASE" | grep "ubuntu:"; then rm -Rf /home/testuser; fi
 RUN TAILSCALED_PATH=`pwd`tailscaled ./tailssh.test -test.v -test.run TestIntegrationSSH
+RUN if echo "$BASE" | grep "ubuntu:"; then rm -Rf /home/testuser; fi
+RUN TAILSCALED_PATH=`pwd`tailscaled ./tailssh.test -test.v -test.run TestIntegrationParamiko
 
 RUN echo "Then run tests as non-root user testuser and make sure tests still pass."
 RUN touch /tmp/tailscalessh.log

tailcfg/tailcfg.go

@@ -158,7 +158,8 @@ type CapabilityVersion int
 //   - 111: 2025-01-14: Client supports a peer having Node.HomeDERP (issue #14636)
 //   - 112: 2025-01-14: Client interprets AllowedIPs of nil as meaning same as Addresses
 //   - 113: 2025-01-20: Client communicates to control whether funnel is enabled by sending Hostinfo.IngressEnabled (#14688)
-const CurrentCapabilityVersion CapabilityVersion = 113
+//   - 114: 2025-01-30: NodeAttrMaxKeyDuration CapMap defined, clients might use it (no tailscaled code change) (#14829)
+const CurrentCapabilityVersion CapabilityVersion = 114
 
 // ID is an integer ID for a user, node, or login allocated by the
 // control plane.
@@ -834,15 +835,22 @@ type Hostinfo struct {
 	// App is used to disambiguate Tailscale clients that run using tsnet.
 	App string `json:",omitempty"` // "k8s-operator", "golinks", ...
 
-	Desktop         opt.Bool       `json:",omitempty"` // if a desktop was detected on Linux
-	Package         string         `json:",omitempty"` // Tailscale package to disambiguate ("choco", "appstore", etc; "" for unknown)
-	DeviceModel     string         `json:",omitempty"` // mobile phone model ("Pixel 3a", "iPhone12,3")
-	PushDeviceToken string         `json:",omitempty"` // macOS/iOS APNs device token for notifications (and Android in the future)
-	Hostname        string         `json:",omitempty"` // name of the host the client runs on
-	ShieldsUp       bool           `json:",omitempty"` // indicates whether the host is blocking incoming connections
-	ShareeNode      bool           `json:",omitempty"` // indicates this node exists in netmap because it's owned by a shared-to user
-	NoLogsNoSupport bool           `json:",omitempty"` // indicates that the user has opted out of sending logs and support
-	WireIngress     bool           `json:",omitempty"` // indicates that the node wants the option to receive ingress connections
+	Desktop         opt.Bool `json:",omitempty"` // if a desktop was detected on Linux
+	Package         string   `json:",omitempty"` // Tailscale package to disambiguate ("choco", "appstore", etc; "" for unknown)
+	DeviceModel     string   `json:",omitempty"` // mobile phone model ("Pixel 3a", "iPhone12,3")
+	PushDeviceToken string   `json:",omitempty"` // macOS/iOS APNs device token for notifications (and Android in the future)
+	Hostname        string   `json:",omitempty"` // name of the host the client runs on
+	ShieldsUp       bool     `json:",omitempty"` // indicates whether the host is blocking incoming connections
+	ShareeNode      bool     `json:",omitempty"` // indicates this node exists in netmap because it's owned by a shared-to user
+	NoLogsNoSupport bool     `json:",omitempty"` // indicates that the user has opted out of sending logs and support
+	// WireIngress indicates that the node would like to be wired up server-side
+	// (DNS, etc) to be able to use Tailscale Funnel, even if it's not currently
+	// enabled. For example, the user might only use it for intermittent
+	// foreground CLI serve sessions, for which they'd like it to work right
+	// away, even if it's disabled most of the time. As an optimization, this is
+	// only sent if IngressEnabled is false, as IngressEnabled implies that this
+	// option is true.
+	WireIngress     bool           `json:",omitempty"`
 	IngressEnabled  bool           `json:",omitempty"` // if the node has any funnel endpoint enabled
 	AllowsUpdate    bool           `json:",omitempty"` // indicates that the node has opted-in to admin-console-drive remote updates
 	Machine         string         `json:",omitempty"` // the current host's machine type (uname -m)
@@ -2021,10 +2029,6 @@ type MapResponse struct {
 	// auto-update setting doesn't change if the tailnet admin flips the
 	// default after the node registered.
 	DefaultAutoUpdate opt.Bool `json:",omitempty"`
-
-	// MaxKeyDuration describes the MaxKeyDuration setting for the tailnet.
-	// If zero, the value is unchanged.
-	MaxKeyDuration time.Duration `json:",omitempty"`
 }
 
 // ClientVersion is information about the latest client version that's available
@@ -2430,6 +2434,12 @@ const (
 	// If multiple values of this key exist, they should be merged in sequence
 	// (replace conflicting keys).
 	NodeAttrServiceHost NodeCapability = "service-host"
+
+	// NodeAttrMaxKeyDuration represents the MaxKeyDuration setting on the
+	// tailnet. The value of this key in [NodeCapMap] will be only one entry of
+	// type float64 representing the duration in seconds. This cap will be
+	// omitted if the tailnet's MaxKeyDuration is the default.
+	NodeAttrMaxKeyDuration NodeCapability = "tailnet.maxKeyDuration"
 )
 
 // SetDNSRequest is a request to add a DNS record.

tempfork/acme/acme.go

@@ -557,7 +557,11 @@ func (c *Client) Accept(ctx context.Context, chal *Challenge) (*Challenge, error
 		return nil, err
 	}
 
-	res, err := c.post(ctx, nil, chal.URI, json.RawMessage("{}"), wantStatus(
+	payload := json.RawMessage("{}")
+	if len(chal.Payload) != 0 {
+		payload = chal.Payload
+	}
+	res, err := c.post(ctx, nil, chal.URI, payload, wantStatus(
 		http.StatusOK,       // according to the spec
 		http.StatusAccepted, // Let's Encrypt: see https://goo.gl/WsJ7VT (acme-divergences.md)
 	))

tempfork/acme/acme_test.go

@@ -875,7 +875,7 @@ func TestTLSALPN01ChallengeCert(t *testing.T) {
 }
 
 func TestTLSChallengeCertOpt(t *testing.T) {
-	key, err := rsa.GenerateKey(rand.Reader, 512)
+	key, err := rsa.GenerateKey(rand.Reader, 1024)
 	if err != nil {
 		t.Fatal(err)
 	}

tempfork/acme/http.go

@@ -15,6 +15,7 @@ import (
 	"io"
 	"math/big"
 	"net/http"
+	"runtime/debug"
 	"strconv"
 	"strings"
 	"time"
@@ -271,9 +272,27 @@ func (c *Client) httpClient() *http.Client {
 }
 
 // packageVersion is the version of the module that contains this package, for
-// sending as part of the User-Agent header. It's set in version_go112.go.
+// sending as part of the User-Agent header.
 var packageVersion string
 
+func init() {
+	// Set packageVersion if the binary was built in modules mode and x/crypto
+	// was not replaced with a different module.
+	info, ok := debug.ReadBuildInfo()
+	if !ok {
+		return
+	}
+	for _, m := range info.Deps {
+		if m.Path != "golang.org/x/crypto" {
+			continue
+		}
+		if m.Replace == nil {
+			packageVersion = m.Version
+		}
+		break
+	}
+}
+
 // userAgent returns the User-Agent header value. It includes the package name,
 // the module version (if available), and the c.UserAgent value (if set).
 func (c *Client) userAgent() string {

tempfork/acme/types.go

@@ -7,6 +7,7 @@ package acme
 import (
 	"crypto"
 	"crypto/x509"
+	"encoding/json"
 	"errors"
 	"fmt"
 	"net/http"
@@ -292,7 +293,7 @@ type Directory struct {
 	// Renewal Information (ARI) Extension.
 	RenewalInfoURL string
 
-	// Term is a URI identifying the current terms of service.
+	// Terms is a URI identifying the current terms of service.
 	Terms string
 
 	// Website is an HTTP or HTTPS URL locating a website
@@ -531,6 +532,16 @@ type Challenge struct {
 	// when this challenge was used.
 	// The type of a non-nil value is *Error.
 	Error error
+
+	// Payload is the JSON-formatted payload that the client sends
+	// to the server to indicate it is ready to respond to the challenge.
+	// When unset, it defaults to an empty JSON object: {}.
+	// For most challenges, the client must not set Payload,
+	// see https://tools.ietf.org/html/rfc8555#section-7.5.1.
+	// Payload is used only for newer challenges (such as "device-attest-01")
+	// where the client must send additional data for the server to validate
+	// the challenge.
+	Payload json.RawMessage
 }
 
 // wireChallenge is ACME JSON challenge representation.

tempfork/sshtest/ssh/client.go

@@ -239,6 +239,14 @@ type ClientConfig struct {
 	//
 	// A Timeout of zero means no timeout.
 	Timeout time.Duration
+
+	// SkipNoneAuth allows skipping the initial "none" auth request. This is unusual
+	// behavior, but it is allowed by [RFC4252 5.2](https://datatracker.ietf.org/doc/html/rfc4252#section-5.2),
+	// and some clients in the wild behave like this. One such client is the paramiko Python
+	// library, which is used in pgadmin4 via the sshtunnel library.
+	// When SkipNoneAuth is true, the client will attempt all configured
+	// [AuthMethod]s until one works, or it runs out.
+	SkipNoneAuth bool
 }
 
 // InsecureIgnoreHostKey returns a function that can be used for

tempfork/sshtest/ssh/client_auth.go

@@ -68,7 +68,16 @@ func (c *connection) clientAuthenticate(config *ClientConfig) error {
 	var lastMethods []string
 
 	sessionID := c.transport.getSessionID()
-	for auth := AuthMethod(new(noneAuth)); auth != nil; {
+	var auth AuthMethod
+	if !config.SkipNoneAuth {
+		auth = AuthMethod(new(noneAuth))
+	} else if len(config.Auth) > 0 {
+		auth = config.Auth[0]
+		for _, a := range config.Auth {
+			lastMethods = append(lastMethods, a.method())
+		}
+	}
+	for auth != nil {
 		ok, methods, err := auth.auth(sessionID, config.User, c.transport, config.Rand, extensions)
 		if err != nil {
 			// On disconnect, return error immediately

tsd/tsd.go

@@ -26,6 +26,7 @@ import (
 	"tailscale.com/health"
 	"tailscale.com/ipn"
 	"tailscale.com/ipn/conffile"
+	"tailscale.com/ipn/desktop"
 	"tailscale.com/net/dns"
 	"tailscale.com/net/netmon"
 	"tailscale.com/net/tsdial"
@@ -52,6 +53,7 @@ type System struct {
 	Netstack       SubSystem[NetstackImpl] // actually a *netstack.Impl
 	DriveForLocal  SubSystem[drive.FileSystemForLocal]
 	DriveForRemote SubSystem[drive.FileSystemForRemote]
+	SessionManager SubSystem[desktop.SessionManager]
 
 	// InitialConfig is initial server config, if any.
 	// It is nil if the node is not in declarative mode.
@@ -110,6 +112,8 @@ func (s *System) Set(v any) {
 		s.DriveForLocal.Set(v)
 	case drive.FileSystemForRemote:
 		s.DriveForRemote.Set(v)
+	case desktop.SessionManager:
+		s.SessionManager.Set(v)
 	default:
 		panic(fmt.Sprintf("unknown type %T", v))
 	}

tsnet/tsnet.go

@@ -930,6 +930,8 @@ func getTSNetDir(logf logger.Logf, confDir, prog string) (string, error) {
 // APIClient returns a tailscale.Client that can be used to make authenticated
 // requests to the Tailscale control server.
 // It requires the user to set tailscale.I_Acknowledge_This_API_Is_Unstable.
+//
+// Deprecated: use AuthenticatedAPITransport with tailscale.com/client/tailscale/v2 instead.
 func (s *Server) APIClient() (*tailscale.Client, error) {
 	if !tailscale.I_Acknowledge_This_API_Is_Unstable {
 		return nil, errors.New("use of Client without setting I_Acknowledge_This_API_Is_Unstable")
@@ -944,6 +946,41 @@ func (s *Server) APIClient() (*tailscale.Client, error) {
 	return c, nil
 }
 
+// I_Acknowledge_This_API_Is_Experimental must be set true to use AuthenticatedAPITransport()
+// for now.
+var I_Acknowledge_This_API_Is_Experimental = false
+
+// AuthenticatedAPITransport provides an HTTP transport that can be used with
+// the control server API without needing additional authentication details. It
+// authenticates using the current client's nodekey.
+//
+// It requires the user to set I_Acknowledge_This_API_Is_Experimental.
+//
+// For example:
+//
+//	import "net/http"
+//	import "tailscale.com/client/tailscale/v2"
+//	import "tailscale.com/tsnet"
+//
+//	var s *tsnet.Server
+//	...
+//	rt, err := s.AuthenticatedAPITransport()
+//	// handler err ...
+//	var client tailscale.Client{HTTP: http.Client{
+//	    Timeout: 1*time.Minute,
+//	    UserAgent: "your-useragent-here",
+//	    Transport: rt,
+//	}}
+func (s *Server) AuthenticatedAPITransport() (http.RoundTripper, error) {
+	if !I_Acknowledge_This_API_Is_Experimental {
+		return nil, errors.New("use of AuthenticatedAPITransport without setting I_Acknowledge_This_API_Is_Experimental")
+	}
+	if err := s.Start(); err != nil {
+		return nil, err
+	}
+	return s.lb.KeyProvingNoiseRoundTripper(), nil
+}
+
 // Listen announces only on the Tailscale network.
 // It will start the server if it has not been started yet.
 //

tstest/deptest/deptest.go

@@ -27,6 +27,7 @@ type DepChecker struct {
 	BadDeps  map[string]string // package => why
 	WantDeps set.Set[string]   // packages expected
 	Tags     string            // comma-separated
+	ExtraEnv []string          // extra environment for "go list" (e.g. CGO_ENABLED=1)
 }
 
 func (c DepChecker) Check(t *testing.T) {
@@ -43,6 +44,7 @@ func (c DepChecker) Check(t *testing.T) {
 	if c.GOARCH != "" {
 		extraEnv = append(extraEnv, "GOARCH="+c.GOARCH)
 	}
+	extraEnv = append(extraEnv, c.ExtraEnv...)
 	cmd.Env = append(os.Environ(), extraEnv...)
 	out, err := cmd.Output()
 	if err != nil {

tstest/integration/tailscaled_deps_test_windows.go

@@ -29,6 +29,7 @@ import (
 	_ "tailscale.com/hostinfo"
 	_ "tailscale.com/ipn"
 	_ "tailscale.com/ipn/conffile"
+	_ "tailscale.com/ipn/desktop"
 	_ "tailscale.com/ipn/ipnlocal"
 	_ "tailscale.com/ipn/ipnserver"
 	_ "tailscale.com/ipn/store"

types/bools/bools.go

@@ -1,7 +1,7 @@
 // Copyright (c) Tailscale Inc & AUTHORS
 // SPDX-License-Identifier: BSD-3-Clause
 
-// Package bools contains the [Int], [Compare], and [Select] functions.
+// Package bools contains the [Int], [Compare], and [IfElse] functions.
 package bools
 
 // Int returns 1 for true and 0 for false.

types/netmap/netmap.go

@@ -79,9 +79,6 @@ type NetworkMap struct {
 	// UserProfiles contains the profile information of UserIDs referenced
 	// in SelfNode and Peers.
 	UserProfiles map[tailcfg.UserID]tailcfg.UserProfileView
-
-	// MaxKeyDuration describes the MaxKeyDuration setting for the tailnet.
-	MaxKeyDuration time.Duration
 }
 
 // User returns nm.SelfNode.User if nm.SelfNode is non-nil, otherwise it returns

types/netmap/nodemut.go

@@ -176,6 +176,5 @@ func mapResponseContainsNonPatchFields(res *tailcfg.MapResponse) bool {
 		// function is called, so it should never be set anyway. But for
 		// completedness, and for tests, check it too:
 		res.PeersChanged != nil ||
-		res.DefaultAutoUpdate != "" ||
-		res.MaxKeyDuration > 0
+		res.DefaultAutoUpdate != ""
 }

types/opt/value.go

@@ -100,31 +100,31 @@ func (o Value[T]) Equal(v Value[T]) bool {
 	return false
 }
 
-// MarshalJSONV2 implements [jsonv2.MarshalerV2].
-func (o Value[T]) MarshalJSONV2(enc *jsontext.Encoder, opts jsonv2.Options) error {
+// MarshalJSONTo implements [jsonv2.MarshalerTo].
+func (o Value[T]) MarshalJSONTo(enc *jsontext.Encoder) error {
 	if !o.set {
 		return enc.WriteToken(jsontext.Null)
 	}
-	return jsonv2.MarshalEncode(enc, &o.value, opts)
+	return jsonv2.MarshalEncode(enc, &o.value)
 }
 
-// UnmarshalJSONV2 implements [jsonv2.UnmarshalerV2].
-func (o *Value[T]) UnmarshalJSONV2(dec *jsontext.Decoder, opts jsonv2.Options) error {
+// UnmarshalJSONFrom implements [jsonv2.UnmarshalerFrom].
+func (o *Value[T]) UnmarshalJSONFrom(dec *jsontext.Decoder) error {
 	if dec.PeekKind() == 'n' {
 		*o = Value[T]{}
 		_, err := dec.ReadToken() // read null
 		return err
 	}
 	o.set = true
-	return jsonv2.UnmarshalDecode(dec, &o.value, opts)
+	return jsonv2.UnmarshalDecode(dec, &o.value)
 }
 
 // MarshalJSON implements [json.Marshaler].
 func (o Value[T]) MarshalJSON() ([]byte, error) {
-	return jsonv2.Marshal(o) // uses MarshalJSONV2
+	return jsonv2.Marshal(o) // uses MarshalJSONTo
 }
 
 // UnmarshalJSON implements [json.Unmarshaler].
 func (o *Value[T]) UnmarshalJSON(b []byte) error {
-	return jsonv2.Unmarshal(b, o) // uses UnmarshalJSONV2
+	return jsonv2.Unmarshal(b, o) // uses UnmarshalJSONFrom
 }

types/prefs/item.go

@@ -152,15 +152,15 @@ func (iv ItemView[T, V]) Equal(iv2 ItemView[T, V]) bool {
 	return iv.ж.Equal(*iv2.ж)
 }
 
-// MarshalJSONV2 implements [jsonv2.MarshalerV2].
-func (iv ItemView[T, V]) MarshalJSONV2(out *jsontext.Encoder, opts jsonv2.Options) error {
-	return iv.ж.MarshalJSONV2(out, opts)
+// MarshalJSONTo implements [jsonv2.MarshalerTo].
+func (iv ItemView[T, V]) MarshalJSONTo(out *jsontext.Encoder) error {
+	return iv.ж.MarshalJSONTo(out)
 }
 
-// UnmarshalJSONV2 implements [jsonv2.UnmarshalerV2].
-func (iv *ItemView[T, V]) UnmarshalJSONV2(in *jsontext.Decoder, opts jsonv2.Options) error {
+// UnmarshalJSONFrom implements [jsonv2.UnmarshalerFrom].
+func (iv *ItemView[T, V]) UnmarshalJSONFrom(in *jsontext.Decoder) error {
 	var x Item[T]
-	if err := x.UnmarshalJSONV2(in, opts); err != nil {
+	if err := x.UnmarshalJSONFrom(in); err != nil {
 		return err
 	}
 	iv.ж = &x
@@ -169,10 +169,10 @@ func (iv *ItemView[T, V]) UnmarshalJSONV2(in *jsontext.Decoder, opts jsonv2.Opti
 
 // MarshalJSON implements [json.Marshaler].
 func (iv ItemView[T, V]) MarshalJSON() ([]byte, error) {
-	return jsonv2.Marshal(iv) // uses MarshalJSONV2
+	return jsonv2.Marshal(iv) // uses MarshalJSONTo
 }
 
 // UnmarshalJSON implements [json.Unmarshaler].
 func (iv *ItemView[T, V]) UnmarshalJSON(b []byte) error {
-	return jsonv2.Unmarshal(b, iv) // uses UnmarshalJSONV2
+	return jsonv2.Unmarshal(b, iv) // uses UnmarshalJSONFrom
 }

types/prefs/list.go

@@ -157,15 +157,15 @@ func (lv ListView[T]) Equal(lv2 ListView[T]) bool {
 	return lv.ж.Equal(*lv2.ж)
 }
 
-// MarshalJSONV2 implements [jsonv2.MarshalerV2].
-func (lv ListView[T]) MarshalJSONV2(out *jsontext.Encoder, opts jsonv2.Options) error {
-	return lv.ж.MarshalJSONV2(out, opts)
+// MarshalJSONTo implements [jsonv2.MarshalerTo].
+func (lv ListView[T]) MarshalJSONTo(out *jsontext.Encoder) error {
+	return lv.ж.MarshalJSONTo(out)
 }
 
-// UnmarshalJSONV2 implements [jsonv2.UnmarshalerV2].
-func (lv *ListView[T]) UnmarshalJSONV2(in *jsontext.Decoder, opts jsonv2.Options) error {
+// UnmarshalJSONFrom implements [jsonv2.UnmarshalerFrom].
+func (lv *ListView[T]) UnmarshalJSONFrom(in *jsontext.Decoder) error {
 	var x List[T]
-	if err := x.UnmarshalJSONV2(in, opts); err != nil {
+	if err := x.UnmarshalJSONFrom(in); err != nil {
 		return err
 	}
 	lv.ж = &x
@@ -174,10 +174,10 @@ func (lv *ListView[T]) UnmarshalJSONV2(in *jsontext.Decoder, opts jsonv2.Options
 
 // MarshalJSON implements [json.Marshaler].
 func (lv ListView[T]) MarshalJSON() ([]byte, error) {
-	return jsonv2.Marshal(lv) // uses MarshalJSONV2
+	return jsonv2.Marshal(lv) // uses MarshalJSONTo
 }
 
 // UnmarshalJSON implements [json.Unmarshaler].
 func (lv *ListView[T]) UnmarshalJSON(b []byte) error {
-	return jsonv2.Unmarshal(b, lv) // uses UnmarshalJSONV2
+	return jsonv2.Unmarshal(b, lv) // uses UnmarshalJSONFrom
 }

types/prefs/map.go

@@ -133,15 +133,15 @@ func (mv MapView[K, V]) Equal(mv2 MapView[K, V]) bool {
 	return mv.ж.Equal(*mv2.ж)
 }
 
-// MarshalJSONV2 implements [jsonv2.MarshalerV2].
-func (mv MapView[K, V]) MarshalJSONV2(out *jsontext.Encoder, opts jsonv2.Options) error {
-	return mv.ж.MarshalJSONV2(out, opts)
+// MarshalJSONTo implements [jsonv2.MarshalerTo].
+func (mv MapView[K, V]) MarshalJSONTo(out *jsontext.Encoder) error {
+	return mv.ж.MarshalJSONTo(out)
 }
 
-// UnmarshalJSONV2 implements [jsonv2.UnmarshalerV2].
-func (mv *MapView[K, V]) UnmarshalJSONV2(in *jsontext.Decoder, opts jsonv2.Options) error {
+// UnmarshalJSONFrom implements [jsonv2.UnmarshalerFrom].
+func (mv *MapView[K, V]) UnmarshalJSONFrom(in *jsontext.Decoder) error {
 	var x Map[K, V]
-	if err := x.UnmarshalJSONV2(in, opts); err != nil {
+	if err := x.UnmarshalJSONFrom(in); err != nil {
 		return err
 	}
 	mv.ж = &x
@@ -150,10 +150,10 @@ func (mv *MapView[K, V]) UnmarshalJSONV2(in *jsontext.Decoder, opts jsonv2.Optio
 
 // MarshalJSON implements [json.Marshaler].
 func (mv MapView[K, V]) MarshalJSON() ([]byte, error) {
-	return jsonv2.Marshal(mv) // uses MarshalJSONV2
+	return jsonv2.Marshal(mv) // uses MarshalJSONTo
 }
 
 // UnmarshalJSON implements [json.Unmarshaler].
 func (mv *MapView[K, V]) UnmarshalJSON(b []byte) error {
-	return jsonv2.Unmarshal(b, mv) // uses UnmarshalJSONV2
+	return jsonv2.Unmarshal(b, mv) // uses UnmarshalJSONFrom
 }

types/prefs/prefs.go

@@ -158,22 +158,22 @@ func (p *preference[T]) SetReadOnly(readonly bool) {
 	p.s.Metadata.ReadOnly = readonly
 }
 
-// MarshalJSONV2 implements [jsonv2.MarshalerV2].
-func (p preference[T]) MarshalJSONV2(out *jsontext.Encoder, opts jsonv2.Options) error {
-	return jsonv2.MarshalEncode(out, &p.s, opts)
+// MarshalJSONTo implements [jsonv2.MarshalerTo].
+func (p preference[T]) MarshalJSONTo(out *jsontext.Encoder) error {
+	return jsonv2.MarshalEncode(out, &p.s)
 }
 
-// UnmarshalJSONV2 implements [jsonv2.UnmarshalerV2].
-func (p *preference[T]) UnmarshalJSONV2(in *jsontext.Decoder, opts jsonv2.Options) error {
-	return jsonv2.UnmarshalDecode(in, &p.s, opts)
+// UnmarshalJSONFrom implements [jsonv2.UnmarshalerFrom].
+func (p *preference[T]) UnmarshalJSONFrom(in *jsontext.Decoder) error {
+	return jsonv2.UnmarshalDecode(in, &p.s)
 }
 
 // MarshalJSON implements [json.Marshaler].
 func (p preference[T]) MarshalJSON() ([]byte, error) {
-	return jsonv2.Marshal(p) // uses MarshalJSONV2
+	return jsonv2.Marshal(p) // uses MarshalJSONTo
 }
 
 // UnmarshalJSON implements [json.Unmarshaler].
 func (p *preference[T]) UnmarshalJSON(b []byte) error {
-	return jsonv2.Unmarshal(b, p) // uses UnmarshalJSONV2
+	return jsonv2.Unmarshal(b, p) // uses UnmarshalJSONFrom
 }

types/prefs/prefs_example/prefs_types.go

@@ -48,10 +48,10 @@ import (
 // the `omitzero` JSON tag option. This option is not supported by the
 // [encoding/json] package as of 2024-08-21; see golang/go#45669.
 // It is recommended that a prefs type implements both
-// [jsonv2.MarshalerV2]/[jsonv2.UnmarshalerV2] and [json.Marshaler]/[json.Unmarshaler]
+// [jsonv2.MarshalerTo]/[jsonv2.UnmarshalerFrom] and [json.Marshaler]/[json.Unmarshaler]
 // to ensure consistent and more performant marshaling, regardless of the JSON package
 // used at the call sites; the standard marshalers can be implemented via [jsonv2].
-// See [Prefs.MarshalJSONV2], [Prefs.UnmarshalJSONV2], [Prefs.MarshalJSON],
+// See [Prefs.MarshalJSONTo], [Prefs.UnmarshalJSONFrom], [Prefs.MarshalJSON],
 // and [Prefs.UnmarshalJSON] for an example implementation.
 type Prefs struct {
 	ControlURL prefs.Item[string]               `json:",omitzero"`
@@ -128,34 +128,34 @@ type AppConnectorPrefs struct {
 	Advertise prefs.Item[bool] `json:",omitzero"`
 }
 
-// MarshalJSONV2 implements [jsonv2.MarshalerV2].
+// MarshalJSONTo implements [jsonv2.MarshalerTo].
 // It is implemented as a performance improvement and to enable omission of
 // unconfigured preferences from the JSON output. See the [Prefs] doc for details.
-func (p Prefs) MarshalJSONV2(out *jsontext.Encoder, opts jsonv2.Options) error {
+func (p Prefs) MarshalJSONTo(out *jsontext.Encoder) error {
 	// The prefs type shadows the Prefs's method set,
 	// causing [jsonv2] to use the default marshaler and avoiding
 	// infinite recursion.
 	type prefs Prefs
-	return jsonv2.MarshalEncode(out, (*prefs)(&p), opts)
+	return jsonv2.MarshalEncode(out, (*prefs)(&p))
 }
 
-// UnmarshalJSONV2 implements [jsonv2.UnmarshalerV2].
-func (p *Prefs) UnmarshalJSONV2(in *jsontext.Decoder, opts jsonv2.Options) error {
+// UnmarshalJSONFrom implements [jsonv2.UnmarshalerFrom].
+func (p *Prefs) UnmarshalJSONFrom(in *jsontext.Decoder) error {
 	// The prefs type shadows the Prefs's method set,
 	// causing [jsonv2] to use the default unmarshaler and avoiding
 	// infinite recursion.
 	type prefs Prefs
-	return jsonv2.UnmarshalDecode(in, (*prefs)(p), opts)
+	return jsonv2.UnmarshalDecode(in, (*prefs)(p))
 }
 
 // MarshalJSON implements [json.Marshaler].
 func (p Prefs) MarshalJSON() ([]byte, error) {
-	return jsonv2.Marshal(p) // uses MarshalJSONV2
+	return jsonv2.Marshal(p) // uses MarshalJSONTo
 }
 
 // UnmarshalJSON implements [json.Unmarshaler].
 func (p *Prefs) UnmarshalJSON(b []byte) error {
-	return jsonv2.Unmarshal(b, p) // uses UnmarshalJSONV2
+	return jsonv2.Unmarshal(b, p) // uses UnmarshalJSONFrom
 }
 
 type marshalAsTrueInJSON struct{}

types/prefs/prefs_test.go

@@ -53,32 +53,32 @@ type TestPrefs struct {
 	Group TestPrefsGroup `json:",omitzero"`
 }
 
-// MarshalJSONV2 implements [jsonv2.MarshalerV2].
-func (p TestPrefs) MarshalJSONV2(out *jsontext.Encoder, opts jsonv2.Options) error {
+// MarshalJSONTo implements [jsonv2.MarshalerTo].
+func (p TestPrefs) MarshalJSONTo(out *jsontext.Encoder) error {
 	// The testPrefs type shadows the TestPrefs's method set,
 	// causing jsonv2 to use the default marshaler and avoiding
 	// infinite recursion.
 	type testPrefs TestPrefs
-	return jsonv2.MarshalEncode(out, (*testPrefs)(&p), opts)
+	return jsonv2.MarshalEncode(out, (*testPrefs)(&p))
 }
 
-// UnmarshalJSONV2 implements [jsonv2.UnmarshalerV2].
-func (p *TestPrefs) UnmarshalJSONV2(in *jsontext.Decoder, opts jsonv2.Options) error {
+// UnmarshalJSONFrom implements [jsonv2.UnmarshalerFrom].
+func (p *TestPrefs) UnmarshalJSONFrom(in *jsontext.Decoder) error {
 	// The testPrefs type shadows the TestPrefs's method set,
 	// causing jsonv2 to use the default unmarshaler and avoiding
 	// infinite recursion.
 	type testPrefs TestPrefs
-	return jsonv2.UnmarshalDecode(in, (*testPrefs)(p), opts)
+	return jsonv2.UnmarshalDecode(in, (*testPrefs)(p))
 }
 
 // MarshalJSON implements [json.Marshaler].
 func (p TestPrefs) MarshalJSON() ([]byte, error) {
-	return jsonv2.Marshal(p) // uses MarshalJSONV2
+	return jsonv2.Marshal(p) // uses MarshalJSONTo
 }
 
 // UnmarshalJSON implements [json.Unmarshaler].
 func (p *TestPrefs) UnmarshalJSON(b []byte) error {
-	return jsonv2.Unmarshal(b, p) // uses UnmarshalJSONV2
+	return jsonv2.Unmarshal(b, p) // uses UnmarshalJSONFrom
 }
 
 // TestBundle is an example structure type that,

types/prefs/struct_list.go

@@ -169,15 +169,15 @@ func (lv StructListView[T, V]) Equal(lv2 StructListView[T, V]) bool {
 	return lv.ж.Equal(*lv2.ж)
 }
 
-// MarshalJSONV2 implements [jsonv2.MarshalerV2].
-func (lv StructListView[T, V]) MarshalJSONV2(out *jsontext.Encoder, opts jsonv2.Options) error {
-	return lv.ж.MarshalJSONV2(out, opts)
+// MarshalJSONTo implements [jsonv2.MarshalerTo].
+func (lv StructListView[T, V]) MarshalJSONTo(out *jsontext.Encoder) error {
+	return lv.ж.MarshalJSONTo(out)
 }
 
-// UnmarshalJSONV2 implements [jsonv2.UnmarshalerV2].
-func (lv *StructListView[T, V]) UnmarshalJSONV2(in *jsontext.Decoder, opts jsonv2.Options) error {
+// UnmarshalJSONFrom implements [jsonv2.UnmarshalerFrom].
+func (lv *StructListView[T, V]) UnmarshalJSONFrom(in *jsontext.Decoder) error {
 	var x StructList[T]
-	if err := x.UnmarshalJSONV2(in, opts); err != nil {
+	if err := x.UnmarshalJSONFrom(in); err != nil {
 		return err
 	}
 	lv.ж = &x
@@ -186,10 +186,10 @@ func (lv *StructListView[T, V]) UnmarshalJSONV2(in *jsontext.Decoder, opts jsonv
 
 // MarshalJSON implements [json.Marshaler].
 func (lv StructListView[T, V]) MarshalJSON() ([]byte, error) {
-	return jsonv2.Marshal(lv) // uses MarshalJSONV2
+	return jsonv2.Marshal(lv) // uses MarshalJSONTo
 }
 
 // UnmarshalJSON implements [json.Unmarshaler].
 func (lv *StructListView[T, V]) UnmarshalJSON(b []byte) error {
-	return jsonv2.Unmarshal(b, lv) // uses UnmarshalJSONV2
+	return jsonv2.Unmarshal(b, lv) // uses UnmarshalJSONFrom
 }

types/prefs/struct_map.go

@@ -149,15 +149,15 @@ func (mv StructMapView[K, T, V]) Equal(mv2 StructMapView[K, T, V]) bool {
 	return mv.ж.Equal(*mv2.ж)
 }
 
-// MarshalJSONV2 implements [jsonv2.MarshalerV2].
-func (mv StructMapView[K, T, V]) MarshalJSONV2(out *jsontext.Encoder, opts jsonv2.Options) error {
-	return mv.ж.MarshalJSONV2(out, opts)
+// MarshalJSONTo implements [jsonv2.MarshalerTo].
+func (mv StructMapView[K, T, V]) MarshalJSONTo(out *jsontext.Encoder) error {
+	return mv.ж.MarshalJSONTo(out)
 }
 
-// UnmarshalJSONV2 implements [jsonv2.UnmarshalerV2].
-func (mv *StructMapView[K, T, V]) UnmarshalJSONV2(in *jsontext.Decoder, opts jsonv2.Options) error {
+// UnmarshalJSONFrom implements [jsonv2.UnmarshalerFrom].
+func (mv *StructMapView[K, T, V]) UnmarshalJSONFrom(in *jsontext.Decoder) error {
 	var x StructMap[K, T]
-	if err := x.UnmarshalJSONV2(in, opts); err != nil {
+	if err := x.UnmarshalJSONFrom(in); err != nil {
 		return err
 	}
 	mv.ж = &x
@@ -166,10 +166,10 @@ func (mv *StructMapView[K, T, V]) UnmarshalJSONV2(in *jsontext.Decoder, opts jso
 
 // MarshalJSON implements [json.Marshaler].
 func (mv StructMapView[K, T, V]) MarshalJSON() ([]byte, error) {
-	return jsonv2.Marshal(mv) // uses MarshalJSONV2
+	return jsonv2.Marshal(mv) // uses MarshalJSONTo
 }
 
 // UnmarshalJSON implements [json.Unmarshaler].
 func (mv *StructMapView[K, T, V]) UnmarshalJSON(b []byte) error {
-	return jsonv2.Unmarshal(b, mv) // uses UnmarshalJSONV2
+	return jsonv2.Unmarshal(b, mv) // uses UnmarshalJSONFrom
 }

util/syspolicy/internal/internal.go

@@ -56,10 +56,10 @@ func EqualJSONForTest(tb TB, j1, j2 jsontext.Value) (s1, s2 string, equal bool)
 		return "", "", true
 	}
 	// Otherwise, format the values for display and return false.
-	if err := j1.Indent("", "\t"); err != nil {
+	if err := j1.Indent(); err != nil {
 		tb.Fatal(err)
 	}
-	if err := j2.Indent("", "\t"); err != nil {
+	if err := j2.Indent(); err != nil {
 		tb.Fatal(err)
 	}
 	return j1.String(), j2.String(), false

util/syspolicy/policy_keys.go

@@ -42,6 +42,12 @@ const (
 	// for auditing purposes. It has no effect when [AlwaysOn] is false.
 	AlwaysOnOverrideWithReason Key = "AlwaysOn.OverrideWithReason"
 
+	// ReconnectAfter is a string value formatted for use with time.ParseDuration()
+	// that defines the duration after which the client should automatically reconnect
+	// to the Tailscale network following a user-initiated disconnect.
+	// An empty string or a zero duration disables automatic reconnection.
+	ReconnectAfter Key = "ReconnectAfter"
+
 	// ExitNodeID is the exit node's node id. default ""; if blank, no exit node is forced.
 	// Exit node ID takes precedence over exit node IP.
 	// To find the node ID, go to /api.md#device.
@@ -176,6 +182,7 @@ var implicitDefinitions = []*setting.Definition{
 	setting.NewDefinition(LogTarget, setting.DeviceSetting, setting.StringValue),
 	setting.NewDefinition(MachineCertificateSubject, setting.DeviceSetting, setting.StringValue),
 	setting.NewDefinition(PostureChecking, setting.DeviceSetting, setting.PreferenceOptionValue),
+	setting.NewDefinition(ReconnectAfter, setting.DeviceSetting, setting.DurationValue),
 	setting.NewDefinition(Tailnet, setting.DeviceSetting, setting.StringValue),
 
 	// User policy settings (can be configured on a user- or device-basis):

util/syspolicy/setting/origin.go

@@ -50,22 +50,22 @@ func (s Origin) String() string {
 	return s.Scope().String()
 }
 
-// MarshalJSONV2 implements [jsonv2.MarshalerV2].
-func (s Origin) MarshalJSONV2(out *jsontext.Encoder, opts jsonv2.Options) error {
-	return jsonv2.MarshalEncode(out, &s.data, opts)
+// MarshalJSONTo implements [jsonv2.MarshalerTo].
+func (s Origin) MarshalJSONTo(out *jsontext.Encoder) error {
+	return jsonv2.MarshalEncode(out, &s.data)
 }
 
-// UnmarshalJSONV2 implements [jsonv2.UnmarshalerV2].
-func (s *Origin) UnmarshalJSONV2(in *jsontext.Decoder, opts jsonv2.Options) error {
-	return jsonv2.UnmarshalDecode(in, &s.data, opts)
+// UnmarshalJSONFrom implements [jsonv2.UnmarshalerFrom].
+func (s *Origin) UnmarshalJSONFrom(in *jsontext.Decoder) error {
+	return jsonv2.UnmarshalDecode(in, &s.data)
 }
 
 // MarshalJSON implements [json.Marshaler].
 func (s Origin) MarshalJSON() ([]byte, error) {
-	return jsonv2.Marshal(s) // uses MarshalJSONV2
+	return jsonv2.Marshal(s) // uses MarshalJSONTo
 }
 
 // UnmarshalJSON implements [json.Unmarshaler].
 func (s *Origin) UnmarshalJSON(b []byte) error {
-	return jsonv2.Unmarshal(b, s) // uses UnmarshalJSONV2
+	return jsonv2.Unmarshal(b, s) // uses UnmarshalJSONFrom
 }

util/syspolicy/setting/raw_item.go

@@ -75,31 +75,31 @@ func (i RawItem) String() string {
 	return fmt.Sprintf("%v%s", i.data.Value.Value, suffix)
 }
 
-// MarshalJSONV2 implements [jsonv2.MarshalerV2].
-func (i RawItem) MarshalJSONV2(out *jsontext.Encoder, opts jsonv2.Options) error {
-	return jsonv2.MarshalEncode(out, &i.data, opts)
+// MarshalJSONTo implements [jsonv2.MarshalerTo].
+func (i RawItem) MarshalJSONTo(out *jsontext.Encoder) error {
+	return jsonv2.MarshalEncode(out, &i.data)
 }
 
-// UnmarshalJSONV2 implements [jsonv2.UnmarshalerV2].
-func (i *RawItem) UnmarshalJSONV2(in *jsontext.Decoder, opts jsonv2.Options) error {
-	return jsonv2.UnmarshalDecode(in, &i.data, opts)
+// UnmarshalJSONFrom implements [jsonv2.UnmarshalerFrom].
+func (i *RawItem) UnmarshalJSONFrom(in *jsontext.Decoder) error {
+	return jsonv2.UnmarshalDecode(in, &i.data)
 }
 
 // MarshalJSON implements [json.Marshaler].
 func (i RawItem) MarshalJSON() ([]byte, error) {
-	return jsonv2.Marshal(i) // uses MarshalJSONV2
+	return jsonv2.Marshal(i) // uses MarshalJSONTo
 }
 
 // UnmarshalJSON implements [json.Unmarshaler].
 func (i *RawItem) UnmarshalJSON(b []byte) error {
-	return jsonv2.Unmarshal(b, i) // uses UnmarshalJSONV2
+	return jsonv2.Unmarshal(b, i) // uses UnmarshalJSONFrom
 }
 
 // RawValue represents a raw policy setting value read from a policy store.
 // It is JSON-marshallable and facilitates unmarshalling of JSON values
 // into corresponding policy setting types, with special handling for JSON numbers
 // (unmarshalled as float64) and JSON string arrays (unmarshalled as []string).
-// See also [RawValue.UnmarshalJSONV2].
+// See also [RawValue.UnmarshalJSONFrom].
 type RawValue struct {
 	opt.Value[any]
 }
@@ -114,16 +114,16 @@ func RawValueOf[T RawValueType](v T) RawValue {
 	return RawValue{opt.ValueOf[any](v)}
 }
 
-// MarshalJSONV2 implements [jsonv2.MarshalerV2].
-func (v RawValue) MarshalJSONV2(out *jsontext.Encoder, opts jsonv2.Options) error {
-	return jsonv2.MarshalEncode(out, v.Value, opts)
+// MarshalJSONTo implements [jsonv2.MarshalerTo].
+func (v RawValue) MarshalJSONTo(out *jsontext.Encoder) error {
+	return jsonv2.MarshalEncode(out, v.Value)
 }
 
-// UnmarshalJSONV2 implements [jsonv2.UnmarshalerV2] by attempting to unmarshal
+// UnmarshalJSONFrom implements [jsonv2.UnmarshalerFrom] by attempting to unmarshal
 // a JSON value as one of the supported policy setting value types (bool, string, uint64, or []string),
 // based on the JSON value type. It fails if the JSON value is an object, if it's a JSON number that
 // cannot be represented as a uint64, or if a JSON array contains anything other than strings.
-func (v *RawValue) UnmarshalJSONV2(in *jsontext.Decoder, opts jsonv2.Options) error {
+func (v *RawValue) UnmarshalJSONFrom(in *jsontext.Decoder) error {
 	var valPtr any
 	switch k := in.PeekKind(); k {
 	case 't', 'f':
@@ -139,7 +139,7 @@ func (v *RawValue) UnmarshalJSONV2(in *jsontext.Decoder, opts jsonv2.Options) er
 	default:
 		panic("unreachable")
 	}
-	if err := jsonv2.UnmarshalDecode(in, valPtr, opts); err != nil {
+	if err := jsonv2.UnmarshalDecode(in, valPtr); err != nil {
 		v.Value.Clear()
 		return err
 	}
@@ -150,12 +150,12 @@ func (v *RawValue) UnmarshalJSONV2(in *jsontext.Decoder, opts jsonv2.Options) er
 
 // MarshalJSON implements [json.Marshaler].
 func (v RawValue) MarshalJSON() ([]byte, error) {
-	return jsonv2.Marshal(v) // uses MarshalJSONV2
+	return jsonv2.Marshal(v) // uses MarshalJSONTo
 }
 
 // UnmarshalJSON implements [json.Unmarshaler].
 func (v *RawValue) UnmarshalJSON(b []byte) error {
-	return jsonv2.Unmarshal(b, v) // uses UnmarshalJSONV2
+	return jsonv2.Unmarshal(b, v) // uses UnmarshalJSONFrom
 }
 
 // RawValues is a map of keyed setting values that can be read from a JSON.

util/syspolicy/setting/snapshot.go

@@ -147,23 +147,23 @@ type snapshotJSON struct {
 	Settings map[Key]RawItem `json:",omitempty"`
 }
 
-// MarshalJSONV2 implements [jsonv2.MarshalerV2].
-func (s *Snapshot) MarshalJSONV2(out *jsontext.Encoder, opts jsonv2.Options) error {
+// MarshalJSONTo implements [jsonv2.MarshalerTo].
+func (s *Snapshot) MarshalJSONTo(out *jsontext.Encoder) error {
 	data := &snapshotJSON{}
 	if s != nil {
 		data.Summary = s.summary
 		data.Settings = s.m
 	}
-	return jsonv2.MarshalEncode(out, data, opts)
+	return jsonv2.MarshalEncode(out, data)
 }
 
-// UnmarshalJSONV2 implements [jsonv2.UnmarshalerV2].
-func (s *Snapshot) UnmarshalJSONV2(in *jsontext.Decoder, opts jsonv2.Options) error {
+// UnmarshalJSONFrom implements [jsonv2.UnmarshalerFrom].
+func (s *Snapshot) UnmarshalJSONFrom(in *jsontext.Decoder) error {
 	if s == nil {
 		return errors.New("s must not be nil")
 	}
 	data := &snapshotJSON{}
-	if err := jsonv2.UnmarshalDecode(in, data, opts); err != nil {
+	if err := jsonv2.UnmarshalDecode(in, data); err != nil {
 		return err
 	}
 	*s = Snapshot{m: data.Settings, sig: deephash.Hash(&data.Settings), summary: data.Summary}
@@ -172,12 +172,12 @@ func (s *Snapshot) UnmarshalJSONV2(in *jsontext.Decoder, opts jsonv2.Options) er
 
 // MarshalJSON implements [json.Marshaler].
 func (s *Snapshot) MarshalJSON() ([]byte, error) {
-	return jsonv2.Marshal(s) // uses MarshalJSONV2
+	return jsonv2.Marshal(s) // uses MarshalJSONTo
 }
 
 // UnmarshalJSON implements [json.Unmarshaler].
 func (s *Snapshot) UnmarshalJSON(b []byte) error {
-	return jsonv2.Unmarshal(b, s) // uses UnmarshalJSONV2
+	return jsonv2.Unmarshal(b, s) // uses UnmarshalJSONFrom
 }
 
 // MergeSnapshots returns a [Snapshot] that contains all [RawItem]s

util/syspolicy/setting/summary.go

@@ -54,24 +54,24 @@ func (s Summary) String() string {
 	return s.data.Scope.String()
 }
 
-// MarshalJSONV2 implements [jsonv2.MarshalerV2].
-func (s Summary) MarshalJSONV2(out *jsontext.Encoder, opts jsonv2.Options) error {
-	return jsonv2.MarshalEncode(out, &s.data, opts)
+// MarshalJSONTo implements [jsonv2.MarshalerTo].
+func (s Summary) MarshalJSONTo(out *jsontext.Encoder) error {
+	return jsonv2.MarshalEncode(out, &s.data)
 }
 
-// UnmarshalJSONV2 implements [jsonv2.UnmarshalerV2].
-func (s *Summary) UnmarshalJSONV2(in *jsontext.Decoder, opts jsonv2.Options) error {
-	return jsonv2.UnmarshalDecode(in, &s.data, opts)
+// UnmarshalJSONFrom implements [jsonv2.UnmarshalerFrom].
+func (s *Summary) UnmarshalJSONFrom(in *jsontext.Decoder) error {
+	return jsonv2.UnmarshalDecode(in, &s.data)
 }
 
 // MarshalJSON implements [json.Marshaler].
 func (s Summary) MarshalJSON() ([]byte, error) {
-	return jsonv2.Marshal(s) // uses MarshalJSONV2
+	return jsonv2.Marshal(s) // uses MarshalJSONTo
 }
 
 // UnmarshalJSON implements [json.Unmarshaler].
 func (s *Summary) UnmarshalJSON(b []byte) error {
-	return jsonv2.Unmarshal(b, s) // uses UnmarshalJSONV2
+	return jsonv2.Unmarshal(b, s) // uses UnmarshalJSONFrom
 }
 
 // SummaryOption is an option that configures [Summary]