From 33d7ad86a6cf0cf4b3f3295698d305c43dd8182d Mon Sep 17 00:00:00 2001
From: Brad Fitzpatrick <bradfitz@tailscale.com>
Date: Sat, 5 Aug 2023 19:07:25 -0700
Subject: [PATCH] android: add INIT_WITH_AUTHKEY intent

e.g.
adb shell am broadcast  -n com.tailscale.ipn/.IPNReceiver -a com.tailscale.ipn.INIT_WITH_AUTHKEY --es authkey "my-super-secret-authkey"

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
---
 android/src/main/AndroidManifest.xml          |  1 +
 .../java/com/tailscale/ipn/IPNReceiver.java   |  4 +++
 .../java/com/tailscale/ipn/IPNService.java    |  2 ++
 cmd/tailscale/callbacks.go                    | 17 ++++++++++--
 cmd/tailscale/main.go                         | 27 +++++++++++++++++++
 5 files changed, 49 insertions(+), 2 deletions(-)

diff --git a/android/src/main/AndroidManifest.xml b/android/src/main/AndroidManifest.xml
index 327951b445..9580299aa1 100644
--- a/android/src/main/AndroidManifest.xml
+++ b/android/src/main/AndroidManifest.xml
@@ -60,6 +60,7 @@
 			<intent-filter>
 				<action android:name="com.tailscale.ipn.CONNECT_VPN" />
 				<action android:name="com.tailscale.ipn.DISCONNECT_VPN" />
+				<action android:name="com.tailscale.ipn.INIT_WITH_AUTHKEY" />
 			</intent-filter>
 		</receiver>
 		<service android:name=".IPNService"
diff --git a/android/src/main/java/com/tailscale/ipn/IPNReceiver.java b/android/src/main/java/com/tailscale/ipn/IPNReceiver.java
index a0f7f32fc5..c6b9dfde40 100644
--- a/android/src/main/java/com/tailscale/ipn/IPNReceiver.java
+++ b/android/src/main/java/com/tailscale/ipn/IPNReceiver.java
@@ -9,6 +9,7 @@
 import android.content.Intent;
 import androidx.work.WorkManager;
 import androidx.work.OneTimeWorkRequest;
+import android.util.Log;
 
 public class IPNReceiver extends BroadcastReceiver {
 
@@ -21,6 +22,9 @@ public void onReceive(Context context, Intent intent) {
             workManager.enqueue(new OneTimeWorkRequest.Builder(StartVPNWorker.class).build());
         } else if (intent.getAction() == "com.tailscale.ipn.DISCONNECT_VPN") {
             workManager.enqueue(new OneTimeWorkRequest.Builder(StopVPNWorker.class).build());
+        } else if (intent.getAction() == "com.tailscale.ipn.INIT_WITH_AUTHKEY") {
+            String key = intent.getStringExtra("authkey");
+            IPNService.setAuthKeyForNextConnect(key);
         }
     }
 }
diff --git a/android/src/main/java/com/tailscale/ipn/IPNService.java b/android/src/main/java/com/tailscale/ipn/IPNService.java
index fe23ae46a7..8bd4a0991b 100644
--- a/android/src/main/java/com/tailscale/ipn/IPNService.java
+++ b/android/src/main/java/com/tailscale/ipn/IPNService.java
@@ -119,6 +119,8 @@ public void updateStatusNotification(String title, String message) {
 		startForeground(App.STATUS_NOTIFICATION_ID, builder.build());
 	}
 
+	public static native void setAuthKeyForNextConnect(String authKey);
+
 	private native void connect();
 	private native void disconnect();
 
diff --git a/cmd/tailscale/callbacks.go b/cmd/tailscale/callbacks.go
index 534e4390a1..f0ecaf0268 100644
--- a/cmd/tailscale/callbacks.go
+++ b/cmd/tailscale/callbacks.go
@@ -33,6 +33,9 @@ var (
 	// onConnectivityChange is notified every time the network
 	// conditions change.
 	onConnectivityChange = make(chan bool, 1)
+	// onSetAuthKeyForNextConnect gets an authkey for use in the next connect
+	// when IPNReceiver receives one.
+	onSetAuthKeyForNextConnect = make(chan string, 1)
 
 	// onGoogleToken receives google ID tokens.
 	onGoogleToken = make(chan string)
@@ -109,12 +112,12 @@ func Java_com_tailscale_ipn_IPNService_disconnect(env *C.JNIEnv, this C.jobject)
 
 //export Java_com_tailscale_ipn_StartVPNWorker_connect
 func Java_com_tailscale_ipn_StartVPNWorker_connect(env *C.JNIEnv, this C.jobject) {
-    requestBackend(ConnectEvent{Enable: true})
+	requestBackend(ConnectEvent{Enable: true})
 }
 
 //export Java_com_tailscale_ipn_StopVPNWorker_disconnect
 func Java_com_tailscale_ipn_StopVPNWorker_disconnect(env *C.JNIEnv, this C.jobject) {
-    requestBackend(ConnectEvent{Enable: false})
+	requestBackend(ConnectEvent{Enable: false})
 }
 
 //export Java_com_tailscale_ipn_App_onConnectivityChanged
@@ -200,3 +203,13 @@ func Java_com_tailscale_ipn_App_onShareIntent(env *C.JNIEnv, cls C.jclass, nfile
 	}
 	onFileShare <- files
 }
+
+//export Java_com_tailscale_ipn_IPNService_setAuthKeyForNextConnect
+func Java_com_tailscale_ipn_IPNService_setAuthKeyForNextConnect(env *C.JNIEnv, this C.jobject, authKeyJStr C.jobject) {
+	jenv := (*jni.Env)(unsafe.Pointer(env))
+	authKey := jni.GoString(jenv, jni.String(authKeyJStr))
+	select {
+	case onSetAuthKeyForNextConnect <- authKey:
+	default:
+	}
+}
diff --git a/cmd/tailscale/main.go b/cmd/tailscale/main.go
index 7a2ce96a5a..89a041dab3 100644
--- a/cmd/tailscale/main.go
+++ b/cmd/tailscale/main.go
@@ -164,6 +164,9 @@ type ConnectEvent struct {
 	Enable bool
 }
 
+type SetAuthKeyEvent struct {
+	AuthKey string
+}
 type CopyEvent struct {
 	Text string
 }
@@ -441,6 +444,27 @@ func (a *App) runBackend() error {
 					go b.backend.StartLoginInteractive()
 					signingIn = true
 				}
+			case SetAuthKeyEvent:
+				authKey := e.AuthKey
+				if b.backend.State() <= ipn.Stopped {
+					log.Printf("using authkey; state=%v", b.backend.State())
+					go func() {
+						prefs := ipn.NewPrefs()
+						prefs.WantRunning = true
+						err := b.backend.Start(ipn.Options{
+							AuthKey:     authKey,
+							UpdatePrefs: prefs,
+						})
+						log.Printf("authkey: Start error = %v", err)
+						if err != nil {
+							fatalErr(err)
+						} else {
+							b.backend.StartLoginInteractive()
+						}
+					}()
+				} else {
+					log.Printf("ignoring authkey in state=%v", b.backend.State())
+				}
 			case SetLoginServerEvent:
 				state.Prefs.ControlURL = e.URL
 				b.backend.SetPrefs(state.Prefs)
@@ -895,6 +919,9 @@ func (a *App) runUI() error {
 					w.Invalidate()
 				}
 			}
+		case authKey := <-onSetAuthKeyForNextConnect:
+			ui.ShowMessage("got authkey")
+			requestBackend(SetAuthKeyEvent{AuthKey: authKey})
 		case p := <-a.prefs:
 			ui.enabled.Value = p.WantRunning
 			ui.runningExit = p.AdvertisesExitNode()