Add secret Run Exit Node option when "debug" is searched for.

And bump tailscale dep, to bring in new ipn.Prefs API and wire up
ExitDNS for Android.

This change has no visible behavior change to anybody unless they
search for "debug" and then hit the "..." menu.

Updates tailscale/tailscale#1738

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>

cmd/tailscale/backend.go

@@ -29,6 +29,7 @@ import (
 	"tailscale.com/types/logger"
 	"tailscale.com/util/dnsname"
 	"tailscale.com/wgengine"
+	"tailscale.com/wgengine/netstack"
 	"tailscale.com/wgengine/router"
 )
 
@@ -120,6 +121,9 @@ func newBackend(dataDir string, jvm *jni.JVM, appCtx jni.Object, store *stateSto
 		return nil, fmt.Errorf("runBackend: NewUserspaceEngine: %v", err)
 	}
 	b.logIDPublic = logID.Public().String()
+	if err := startNetstack(log.Printf, dialer, engine); err != nil {
+		return nil, fmt.Errorf("startNetstack: %w", err)
+	}
 	local, err := ipnlocal.NewLocalBackend(logf, b.logIDPublic, store, dialer, engine)
 	if err != nil {
 		engine.Close()
@@ -428,3 +432,17 @@ func (b *backend) getDNSBaseConfig() (dns.OSConfig, error) {
 
 	return config, nil
 }
+
+func startNetstack(logf logger.Logf, dialer *tsdial.Dialer, e wgengine.Engine) error {
+	tunDev, magicConn, ok := e.(wgengine.InternalsGetter).GetInternals()
+	if !ok {
+		return fmt.Errorf("%T is not a wgengine.InternalsGetter", e)
+	}
+	ns, err := netstack.Create(logf, tunDev, e, magicConn, dialer)
+	if err != nil {
+		return fmt.Errorf("netstack.Create: %w", err)
+	}
+	ns.ProcessLocalIPs = false
+	ns.ProcessSubnets = true
+	return ns.Start()
+}

cmd/tailscale/main.go

@@ -188,6 +188,7 @@ type (
 	WebAuthEvent    struct{}
 	GoogleAuthEvent struct{}
 	LogoutEvent     struct{}
+	BeExitNodeEvent bool
 )
 
 // serverOAuthID is the OAuth ID of the tailscale-android server, used
@@ -416,6 +417,9 @@ func (a *App) runBackend() error {
 			case ToggleEvent:
 				state.Prefs.WantRunning = !state.Prefs.WantRunning
 				go b.backend.SetPrefs(state.Prefs)
+			case BeExitNodeEvent:
+				state.Prefs.SetAdvertiseExitNode(bool(e))
+				go b.backend.SetPrefs(state.Prefs)
 			case WebAuthEvent:
 				if !signingIn {
 					go b.backend.StartLoginInteractive()
@@ -860,6 +864,7 @@ func (a *App) runUI() error {
 			}
 		case p := <-a.prefs:
 			ui.enabled.Value = p.WantRunning
+			ui.runningExit = p.AdvertisesExitNode()
 			w.Invalidate()
 		case state.browseURL = <-a.browseURLs:
 			ui.signinType = noSignin
@@ -1070,6 +1075,8 @@ func (a *App) processUIEvents(w *app.Window, events []UIEvent, act jni.Object, s
 			logMarker := fmt.Sprintf("BUG-%v-%v-%v", backendLogID, time.Now().UTC().Format("20060102150405Z"), randHex(8))
 			log.Printf("user bugreport: %s", logMarker)
 			w.WriteClipboard(logMarker)
+		case BeExitNodeEvent:
+			requestBackend(e)
 		case WebAuthEvent:
 			a.store.WriteString(loginMethodPrefKey, loginMethodWeb)
 			requestBackend(e)

cmd/tailscale/ui.go

@@ -10,6 +10,7 @@ import (
 	"fmt"
 	"image"
 	"image/color"
+	"strings"
 	"time"
 
 	"gioui.org/f32"
@@ -70,6 +71,9 @@ type UI struct {
 		list    layout.List
 	}
 
+	showDebugMenu bool
+	runningExit   bool // are we an exit node now?
+
 	intro struct {
 		list  layout.List
 		start widget.Clickable
@@ -84,6 +88,7 @@ type UI struct {
 		copy   widget.Clickable
 		reauth widget.Clickable
 		bug    widget.Clickable
+		beExit widget.Clickable
 		exits  widget.Clickable
 		logout widget.Clickable
 	}
@@ -260,7 +265,11 @@ func (ui *UI) layout(gtx layout.Context, sysIns system.Insets, state *clientStat
 
 	for _, e := range ui.search.Events() {
 		if _, ok := e.(widget.ChangeEvent); ok {
-			events = append(events, SearchEvent{Query: ui.search.Text()})
+			text := ui.search.Text()
+			if strings.EqualFold(text, "debug") {
+				ui.showDebugMenu = true
+			}
+			events = append(events, SearchEvent{Query: text})
 			break
 		}
 	}
@@ -319,6 +328,16 @@ func (ui *UI) layout(gtx layout.Context, sysIns system.Insets, state *clientStat
 		ui.showCopied(gtx, "bug report marker to clipboard")
 	}
 
+	if ui.menuClicked(&ui.menu.beExit) {
+		ui.runningExit = !ui.runningExit
+		events = append(events, BeExitNodeEvent(ui.runningExit))
+		if ui.runningExit {
+			ui.showMessage(gtx, "Running exit node")
+		} else {
+			ui.showMessage(gtx, "Stopped running exit node")
+		}
+	}
+
 	if ui.menuClicked(&ui.menu.exits) || ui.openExitDialog.Clicked() {
 		ui.exitDialog.show = true
 	}
@@ -981,6 +1000,15 @@ func (ui *UI) layoutMenu(gtx layout.Context, sysIns system.Insets, expiry time.T
 				menuItem{title: "Reauthenticate", btn: &menu.reauth},
 				menuItem{title: "Log out", btn: &menu.logout},
 			)
+			if ui.runningExit || ui.showDebugMenu {
+				var title string
+				if ui.runningExit {
+					title = "Stop running exit node [BETA]"
+				} else {
+					title = "Run exit node [BETA]"
+				}
+				items = append(items, menuItem{title: title, btn: &menu.beExit})
+			}
 			return layoutMenu(ui.theme, gtx, items, func(gtx C) D {
 				var expiryStr string
 				const fmtStr = time.Stamp

go.mod

@@ -10,7 +10,7 @@ require (
 	golang.org/x/sys v0.0.0-20211205182925-97ca703d548d
 	golang.zx2c4.com/wireguard v0.0.0-20211116201604-de7c702ace45
 	inet.af/netaddr v0.0.0-20211027220019-c74959edd3b6
-	tailscale.com v1.1.1-0.20220106164417-64c2657448c9
+	tailscale.com v1.1.1-0.20220107180532-1a4e8da0849f
 )
 
 require (

go.sum

@@ -705,3 +705,7 @@ tailscale.com v1.1.1-0.20220103195654-dd45bba76b3a h1:f1Ixr2b9pnSeVLRt1caMxd4rJV
 tailscale.com v1.1.1-0.20220103195654-dd45bba76b3a/go.mod h1:kjVy3ji2OH5lZhPLIIRacoY3CN4Bo3Yyb2mtoM8nfJ4=
 tailscale.com v1.1.1-0.20220106164417-64c2657448c9 h1:LFkTqkAfdB+FzWS0KmOwv2Y5ba0Kbbc3IQfHi6G09fA=
 tailscale.com v1.1.1-0.20220106164417-64c2657448c9/go.mod h1:kjVy3ji2OH5lZhPLIIRacoY3CN4Bo3Yyb2mtoM8nfJ4=
+tailscale.com v1.1.1-0.20220107005935-1b426cc232c0 h1:Z2+Z5HEPrInsP7BlE/2kMohRRWRvjxzJiLryhsrT+/c=
+tailscale.com v1.1.1-0.20220107005935-1b426cc232c0/go.mod h1:kjVy3ji2OH5lZhPLIIRacoY3CN4Bo3Yyb2mtoM8nfJ4=
+tailscale.com v1.1.1-0.20220107180532-1a4e8da0849f h1:PIv9L0qXK6HZuAer6hg6mmSByzJ5jv1MR5J7Wlbnfek=
+tailscale.com v1.1.1-0.20220107180532-1a4e8da0849f/go.mod h1:kjVy3ji2OH5lZhPLIIRacoY3CN4Bo3Yyb2mtoM8nfJ4=