Intent interface for MainService

README.md

@@ -91,10 +91,91 @@ An example `defaults.json` with completely new defaults (not all entries need to
     "portReverse": 5555,
     "portRepeater": 5556,
     "scaling": 0.7,
-    "password": "supersecure"
+    "viewOnly": false,
+    "fileTranfer": true,
+    "password": "supersecure",
+    "accessKey": "evenmoresecure"
 }
 ```
 
+### Remote Control via the Intent Interface
+
+droidVNC-NG features a remote control interface by means of Intents. This allows starting the VNC
+server from other apps or on certain events. It is designed to be working with automation apps
+like [MacroDroid](https://www.macrodroid.com/), [Automate](https://llamalab.com/automate/) or
+[Tasker](https://tasker.joaoapps.com/) as well as to be called from code.
+
+You basically send an explicit Intent to `net.christianbeier.droidvnc_ng.MainService` with one of
+the following Actions and associated Extras set:
+
+* `net.christianbeier.droidvnc_ng.ACTION_START`: Starts the server.
+  * `net.christianbeier.droidvnc_ng.EXTRA_ACCESS_KEY`: Required String Extra containing the remote control interface's access key. You can get/set this from the Admin Panel. 
+  * `net.christianbeier.droidvnc_ng.EXTRA_REQUEST_ID`: Optional String Extra containing a unique id for this request. Used to identify the answer from the service.
+  * `net.christianbeier.droidvnc_ng.EXTRA_PORT`: Optional Integer Extra setting the listening port. Set to `-1` to disable listening.
+  * `net.christianbeier.droidvnc_ng.EXTRA_PASSWORD`: Optional String Extra containing VNC password.
+  * `net.christianbeier.droidvnc_ng.EXTRA_SCALING`: Optional Float Extra between 0.0 and 1.0 describing the server-side framebuffer scaling.
+  * `net.christianbeier.droidvnc_ng.EXTRA_VIEW_ONLY`:  Optional Boolean Extra toggling view-only mode.
+  * `net.christianbeier.droidvnc_ng.EXTRA_FILE_TRANSFER`: Optional Boolean Extra toggling the file transfer feature.
+
+* `net.christianbeier.droidvnc_ng.ACTION_CONNECT_REVERSE`: Make an outbound connection to a listening viewer.
+  * `net.christianbeier.droidvnc_ng.EXTRA_ACCESS_KEY`: Required String Extra containing the remote control interface's access key. You can get/set this from the Admin Panel.
+  * `net.christianbeier.droidvnc_ng.EXTRA_REQUEST_ID`: Optional String Extra containing a unique id for this request. Used to identify the answer from the service.
+  * `net.christianbeier.droidvnc_ng.EXTRA_HOST`: Required String Extra setting the host to connect to.
+  * `net.christianbeier.droidvnc_ng.EXTRA_PORT`: Optional Integer Extra setting the remote port.
+
+* `net.christianbeier.droidvnc_ng.ACTION_CONNECT_REPEATER` Make an outbound connection to a repeater.
+  * `net.christianbeier.droidvnc_ng.EXTRA_ACCESS_KEY`: Required String Extra containing the remote control interface's access key. You can get/set this from the Admin Panel.
+  * `net.christianbeier.droidvnc_ng.EXTRA_REQUEST_ID`: Optional String Extra containing a unique id for this request. Used to identify the answer from the service.
+  * `net.christianbeier.droidvnc_ng.EXTRA_HOST`: Required String Extra setting the host to connect to.
+  * `net.christianbeier.droidvnc_ng.EXTRA_PORT`: Optional Integer Extra setting the remote port.
+  * `net.christianbeier.droidvnc_ng.EXTRA_REPEATER_ID`: Required String Extra setting the ID on the repeater.
+
+* `net.christianbeier.droidvnc_ng.ACTION_STOP`: Stops the server.
+  * `net.christianbeier.droidvnc_ng.EXTRA_ACCESS_KEY`: Required String Extra containing the remote control interface's access key. You can get/set this from the Admin Panel.
+  * `net.christianbeier.droidvnc_ng.EXTRA_REQUEST_ID`: Optional String Extra containing a unique id for this request. Used to identify the answer from the service.
+
+The service answers with a Broadcast Intent with its Action mirroring your request:
+
+* Action: one of the above Actions you requested
+  * `net.christianbeier.droidvnc_ng.EXTRA_REQUEST_ID`: The request id this answer is for.
+  * `net.christianbeier.droidvnc_ng.EXTRA_REQUEST_SUCCESS`: Boolean Extra describing the outcome of the request.
+
+#### Examples
+
+##### Start a password-protected view-only server on port 5901
+
+Using `adb shell am` syntax:
+
+```shell
+adb shell am start-foreground-service \
+ -n net.christianbeier.droidvnc_ng/.MainService \
+ -a net.christianbeier.droidvnc_ng.ACTION_START \
+ --es net.christianbeier.droidvnc_ng.EXTRA_ACCESS_KEY de32550a6efb43f8a5d145e6c07b2cde \
+ --es net.christianbeier.droidvnc_ng.EXTRA_REQUEST_ID abc123 \
+ --ei net.christianbeier.droidvnc_ng.EXTRA_PORT 5901 \
+ --es net.christianbeier.droidvnc_ng.EXTRA_PASSWORD supersecure \
+ --ez net.christianbeier.droidvnc_ng.EXTRA_VIEW_ONLY true
+```
+
+##### Make an outbound connection to a listening viewer from the running server
+
+For example from Java code:
+
+See [MainActivity.java](app/src/main/java/net/christianbeier/droidvnc_ng/MainActivity.java).
+
+##### Stop the server again
+
+Using `adb shell am` syntax again:
+
+```shell
+adb shell am start-foreground-service \
+ -n net.christianbeier.droidvnc_ng/.MainService \
+ -a net.christianbeier.droidvnc_ng.ACTION_STOP \
+ --es net.christianbeier.droidvnc_ng.EXTRA_ACCESS_KEY de32550a6efb43f8a5d145e6c07b2cde \
+ --es net.christianbeier.droidvnc_ng.EXTRA_REQUEST_ID def456
+```
+
+
 ## Notes
 
 * Requires at least Android 7.

app/src/main/AndroidManifest.xml

@@ -23,9 +23,16 @@
             </intent-filter>
         </receiver>
 
+        <!--
+            We export the MainService without a permission to enable 3rd party apps to send
+            send Intents to it (otherwise they would have to know about the permission at build
+            time). Access is secured differently by an access key Intent senders have to supply.
+            As only explicit Intents are handled (i.e. no intent-filter), this is secure.
+        -->
         <service
             android:name=".MainService"
             android:enabled="true"
+            android:exported="true"
             android:foregroundServiceType="mediaProjection" />
 
         <service

app/src/main/cpp/droidvnc-ng.c

@@ -461,3 +461,7 @@ JNIEXPORT jint JNICALL Java_net_christianbeier_droidvnc_1ng_MainService_vncGetFr
 
     return theScreen->height;
 }
+
+JNIEXPORT jboolean JNICALL Java_net_christianbeier_droidvnc_1ng_MainService_vncIsActive(JNIEnv *env, jobject thiz) {
+    return theScreen && rfbIsActive(theScreen);
+}

app/src/main/java/net/christianbeier/droidvnc_ng/Constants.java

@@ -22,11 +22,20 @@
 package net.christianbeier.droidvnc_ng;
 
 public class Constants {
+    /*
+        user settings
+     */
     public static final String PREFS_KEY_SETTINGS_PORT = "settings_port";
     public static final String PREFS_KEY_SETTINGS_PASSWORD = "settings_password" ;
     public static final String PREFS_KEY_SETTINGS_START_ON_BOOT = "settings_start_on_boot" ;
     public static final String PREFS_KEY_SETTINGS_SCALING = "settings_scaling" ;
-    public static final String PREFS_KEY_REVERSE_VNC_LAST_HOST = "reverse_vnc_last_host" ;
-    public static final String PREFS_KEY_REPEATER_VNC_LAST_HOST = "repeater_vnc_last_host" ;
-    public static final String PREFS_KEY_REPEATER_VNC_LAST_ID = "repeater_vnc_last_id" ;
+    public static final String PREFS_KEY_SETTINGS_VIEW_ONLY = "settings_view_only" ;
+    public static final String PREFS_KEY_SETTINGS_ACCESS_KEY = "settings_access_key";
+    public static final String PREFS_KEY_SETTINGS_FILE_TRANSFER = "settings_file_transfer";
+
+    /*
+        persisted runtime values shared between components
+     */
+    public static final String PREFS_KEY_SERVER_LAST_SCALING = "server_last_scaling" ;
+    public static final String PREFS_KEY_INPUT_LAST_ENABLED = "input_last_enabled" ;
 }

app/src/main/java/net/christianbeier/droidvnc_ng/Defaults.kt

@@ -22,17 +22,21 @@
 package net.christianbeier.droidvnc_ng
 
 import android.content.Context
+import android.content.SharedPreferences
 import android.util.Log
-import java.io.File
+import androidx.preference.PreferenceManager
 import kotlinx.serialization.*
 import kotlinx.serialization.json.*
+import java.io.File
+import java.util.UUID
 
 
 @OptIn(ExperimentalSerializationApi::class)
 @Serializable
 class Defaults {
     companion object {
         private const val TAG = "Defaults"
+        private const val PREFS_KEY_DEFAULTS_ACCESS_KEY = "defaults_access_key"
     }
 
     @EncodeDefault
@@ -51,23 +55,56 @@ class Defaults {
     var scaling = 1.0f
         private set
 
+    @EncodeDefault
+    var viewOnly = false
+        private set
+
+    @EncodeDefault
+    var fileTranfer = true
+        private set
+
     @EncodeDefault
     var password = ""
         private set
+
+    @EncodeDefault
+    var accessKey = ""
+        private set
     /*
        NB if adding fields here, don't forget to add their copying in the constructor as well!
      */
 
     constructor(context: Context) {
+        /*
+            persist randomly generated defaults
+         */
+        val prefs = PreferenceManager.getDefaultSharedPreferences(context)
+        val defaultAccessKey = prefs.getString(PREFS_KEY_DEFAULTS_ACCESS_KEY, null)
+        if (defaultAccessKey == null) {
+            val ed: SharedPreferences.Editor = prefs.edit()
+            ed.putString(
+                PREFS_KEY_DEFAULTS_ACCESS_KEY,
+                UUID.randomUUID().toString().replace("-".toRegex(), "")
+            )
+            ed.apply()
+        }
+        this.accessKey = prefs.getString(PREFS_KEY_DEFAULTS_ACCESS_KEY, null)!!
+
+        /*
+            read provided defaults
+         */
         val jsonFile = File(context.getExternalFilesDir(null), "defaults.json")
         try {
             val jsonString = jsonFile.readText()
             val readDefault = Json.decodeFromString<Defaults>(jsonString)
             this.port = readDefault.port
             this.portReverse = readDefault.portReverse
             this.portRepeater = readDefault.portRepeater
+            this.fileTranfer = readDefault.fileTranfer
             this.scaling = readDefault.scaling
+            this.viewOnly = readDefault.viewOnly
             this.password = readDefault.password
+            this.accessKey = readDefault.accessKey
             // add here!
         } catch (e: Exception) {
             Log.w(TAG, "${e.message}")

app/src/main/java/net/christianbeier/droidvnc_ng/InputRequestActivity.java

@@ -28,6 +28,7 @@
 import android.util.Log;
 
 import androidx.appcompat.app.AppCompatActivity;
+import androidx.preference.PreferenceManager;
 
 public class InputRequestActivity extends AppCompatActivity {
 
@@ -39,7 +40,13 @@ public class InputRequestActivity extends AppCompatActivity {
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
 
-        if(!InputService.isEnabled()) {
+        // if VIEW_ONLY is set, bail out early without bothering the user
+        if(getIntent().getBooleanExtra(MainService.EXTRA_VIEW_ONLY, new Defaults(this).getViewOnly())) {
+            postResultAndFinish(false);
+            return;
+        }
+
+        if(!InputService.isConnected()) {
             new AlertDialog.Builder(this)
                     .setCancelable(false)
                     .setTitle(R.string.input_a11y_title)
@@ -67,7 +74,7 @@ protected void onActivityResult(int requestCode, int resultCode, Intent data) {
         super.onActivityResult(requestCode, resultCode, data);
         if (requestCode == REQUEST_INPUT) {
             Log.d(TAG, "onActivityResult");
-            postResultAndFinish(InputService.isEnabled());
+            postResultAndFinish(InputService.isConnected());
         }
     }
 
@@ -81,6 +88,7 @@ private void postResultAndFinish(boolean isA11yEnabled) {
         Intent intent = new Intent(this, MainService.class);
         intent.setAction(MainService.ACTION_HANDLE_INPUT_RESULT);
         intent.putExtra(MainService.EXTRA_INPUT_RESULT, isA11yEnabled);
+        intent.putExtra(MainService.EXTRA_ACCESS_KEY, PreferenceManager.getDefaultSharedPreferences(this).getString(Constants.PREFS_KEY_SETTINGS_ACCESS_KEY, new Defaults(this).getAccessKey()));
         startService(intent);
         finish();
     }

app/src/main/java/net/christianbeier/droidvnc_ng/InputService.java

@@ -51,6 +51,12 @@ public synchronized void onCancelled(GestureDescription gestureDescription) {
 	private static final String TAG = "InputService";
 
 	private static InputService instance;
+	/**
+        * Scaling factor that's applied to incoming pointer events by dividing coordinates by
+        * the given factor.
+        */
+	static float scaling;
+	static boolean isEnabled;
 
 	private Handler mMainHandler;
 
@@ -64,7 +70,6 @@ public synchronized void onCancelled(GestureDescription gestureDescription) {
 	private boolean mIsKeyDelDown;
 	private boolean mIsKeyEscDown;
 
-	private float mScaling;
 
 	private final GestureCallback mGestureCallback = new GestureCallback();
 
@@ -80,8 +85,9 @@ public void onServiceConnected()
 	{
 		super.onServiceConnected();
 		instance = this;
+		isEnabled = PreferenceManager.getDefaultSharedPreferences(this).getBoolean(Constants.PREFS_KEY_INPUT_LAST_ENABLED, !new Defaults(this).getViewOnly());
+		scaling = PreferenceManager.getDefaultSharedPreferences(this).getFloat(Constants.PREFS_KEY_SERVER_LAST_SCALING, new Defaults(this).getScaling());
 		mMainHandler = new Handler(instance.getMainLooper());
-		mScaling = PreferenceManager.getDefaultSharedPreferences(this).getFloat(Constants.PREFS_KEY_SETTINGS_SCALING, new Defaults(this).getScaling());
 		Log.i(TAG, "onServiceConnected");
 	}
 
@@ -92,32 +98,22 @@ public void onDestroy() {
 		Log.i(TAG, "onDestroy");
 	}
 
-	public static boolean isEnabled()
+	public static boolean isConnected()
 	{
 		return instance != null;
 	}
 
-	/**
-	 * Set scaling factor that's applied to incoming pointer events by dividing coordinates by
-	 * the given factor.
-	 * @param scaling The scaling factor as a real number.
-	 * @return Whether scaling was applied or not.
-	 */
-	public static boolean setScaling(float scaling) {
-		try {
-			instance.mScaling = scaling;
-			return true;
-		} catch (Exception e) {
-			return false;
-		}
-	}
 
 	@SuppressWarnings("unused")
 	public static void onPointerEvent(int buttonMask, int x, int y, long client) {
 
+		if(!isEnabled) {
+			return;
+		}
+
 		try {
-			x /= instance.mScaling;
-			y /= instance.mScaling;
+			x /= scaling;
+			y /= scaling;
 
 			/*
 			    left mouse button
@@ -172,6 +168,11 @@ public static void onPointerEvent(int buttonMask, int x, int y, long client) {
 	}
 
 	public static void onKeyEvent(int down, long keysym, long client) {
+
+		if(!isEnabled) {
+			return;
+		}
+
 		Log.d(TAG, "onKeyEvent: keysym " + keysym + " down " + down + " by client " + client);
 
 		/*
@@ -235,6 +236,11 @@ public static void onKeyEvent(int down, long keysym, long client) {
 	}
 
 	public static void onCutText(String text, long client) {
+
+		if(!isEnabled) {
+			return;
+		}
+
 		Log.d(TAG, "onCutText: text '" + text + "' by client " + client);
 
 		try {