add support for peer discovery over BLE

app/build.gradle

@@ -4,13 +4,13 @@ plugins {
 }
 
 android {
-    compileSdkVersion 29
+    compileSdkVersion 31
     buildToolsVersion "30.0.3"
 
     defaultConfig {
         applicationId "eu.neilalexander.yggdrasil"
         minSdkVersion 21
-        targetSdkVersion 29
+        targetSdkVersion 31
         versionCode 13
         versionName "0.1-013"
 
@@ -37,6 +37,7 @@ android {
             minifyEnabled false
             proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
             signingConfig = signingConfigs.getByName("yggdrasil")
+            matchingFallbacks = ['release']
         }
     }
     compileOptions {
@@ -51,12 +52,19 @@ android {
 dependencies {
     implementation fileTree(include: ['*.aar'], dir: 'libs')
     implementation "org.jetbrains.kotlin:kotlin-stdlib:$kotlin_version"
+    implementation "org.jetbrains.kotlinx:kotlinx-coroutines-core:1.7.3"
     implementation 'androidx.core:core-ktx:1.5.0'
     implementation 'androidx.appcompat:appcompat:1.3.0'
     implementation 'com.google.android.material:material:1.3.0'
     implementation 'androidx.constraintlayout:constraintlayout:2.0.4'
     implementation 'androidx.preference:preference-ktx:1.1.0'
+    implementation 'com.guolindev.permissionx:permissionx:1.6.4'
     testImplementation 'junit:junit:4.+'
     androidTestImplementation 'androidx.test.ext:junit:1.1.2'
     androidTestImplementation 'androidx.test.espresso:espresso-core:3.3.0'
+    implementation('org.akselrod.blemesh:lib:0.0.1') {
+        version {
+	    branch = 'main'
+        }
+    }
 }

app/src/main/AndroidManifest.xml

@@ -6,6 +6,10 @@
     <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
     <uses-permission android:name="android.permission.FOREGROUND_SERVICE"/>
     <uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED" />
+    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
+    <uses-permission android:name="android.permission.BLUETOOTH_ADVERTISE" />
+    <uses-permission android:name="android.permission.BLUETOOTH_CONNECT" />
+    <uses-permission android:name="android.permission.BLUETOOTH_SCAN" />
 
     <application
         android:name=".GlobalApplication"
@@ -41,6 +45,7 @@
 
         <service
             android:name=".PacketTunnelProvider"
+            android:foregroundServiceType="location"
             android:permission="android.permission.BIND_VPN_SERVICE"
             android:exported="true">
             <intent-filter>
@@ -67,4 +72,4 @@
         </receiver>
     </application>
 
-</manifest>
+</manifest>

app/src/main/java/eu/neilalexander/yggdrasil/ConfigurationProxy.kt

@@ -55,6 +55,7 @@ object ConfigurationProxy {
             json.put("AdminListen", "none")
             json.put("IfName", "none")
             json.put("IfMTU", 65535)
+            json.put("Listen", JSONArray(arrayOf("tcp://127.0.0.1:9004")))
 
             if (json.getJSONArray("MulticastInterfaces").get(0) is String) {
                 var ar = JSONArray()
@@ -94,4 +95,4 @@ object ConfigurationProxy {
                 (json.getJSONArray("MulticastInterfaces").get(0) as JSONObject).put("Beacon", value)
             }
         }
-}
+}

app/src/main/java/eu/neilalexander/yggdrasil/GlobalApplication.kt

@@ -10,6 +10,8 @@ import androidx.annotation.RequiresApi
 import androidx.core.app.NotificationCompat
 
 const val PREF_KEY_ENABLED = "enabled"
+const val BLE_ENABLED = "ble"
+const val CODED_PHY_ENABLED = "codedPhy"
 const val MAIN_CHANNEL_ID = "Yggdrasil Service"
 
 class GlobalApplication: Application(), YggStateReceiver.StateReceiver {
@@ -68,7 +70,7 @@ fun createServiceNotification(context: Context, state: State): Notification {
     val intent = Intent(context, MainActivity::class.java).apply {
         this.flags = Intent.FLAG_ACTIVITY_NEW_TASK or Intent.FLAG_ACTIVITY_CLEAR_TASK
     }
-    val pendingIntent: PendingIntent = PendingIntent.getActivity(context, 0, intent, PendingIntent.FLAG_UPDATE_CURRENT)
+    val pendingIntent: PendingIntent = PendingIntent.getActivity(context, 0, intent, PendingIntent.FLAG_UPDATE_CURRENT or PendingIntent.FLAG_IMMUTABLE)
 
     val text = when (state) {
         State.Disabled -> context.getText(R.string.tile_disabled)
@@ -119,4 +121,4 @@ private fun createNotificationChannels(context: Context) {
             context.getSystemService(Context.NOTIFICATION_SERVICE) as NotificationManager
         notificationManager.createNotificationChannel(channel)
     }
-}
+}

app/src/main/java/eu/neilalexander/yggdrasil/MainActivity.kt

@@ -1,9 +1,11 @@
 package eu.neilalexander.yggdrasil
 
+import android.Manifest
 import android.app.Activity
 import android.content.*
 import android.graphics.Color
 import android.net.VpnService
+import android.os.Build
 import android.os.Bundle
 import android.widget.Switch
 import android.widget.TextView
@@ -14,6 +16,7 @@ import androidx.appcompat.widget.LinearLayoutCompat
 import androidx.core.content.edit
 import androidx.localbroadcastmanager.content.LocalBroadcastManager
 import androidx.preference.PreferenceManager
+import com.permissionx.guolindev.PermissionX
 import eu.neilalexander.yggdrasil.PacketTunnelProvider.Companion.STATE_INTENT
 import mobile.Mobile
 import org.json.JSONArray
@@ -43,6 +46,46 @@ class MainActivity : AppCompatActivity() {
         }
     }
 
+    private fun checkBLEPermissions() {
+        val preferences = PreferenceManager.getDefaultSharedPreferences(this.baseContext)
+        val bleEnabled = preferences.getBoolean(BLE_ENABLED, (Build.VERSION.SDK_INT >= Build.VERSION_CODES.S))
+        if (!bleEnabled) {
+            return
+        }
+
+        PermissionX.init(this)
+            .permissions(
+                Manifest.permission.ACCESS_FINE_LOCATION,
+                Manifest.permission.BLUETOOTH_ADVERTISE,
+                Manifest.permission.BLUETOOTH_CONNECT,
+                Manifest.permission.BLUETOOTH_SCAN,
+            )
+            .onExplainRequestReason { scope, deniedList ->
+                scope.showRequestReasonDialog(
+                    deniedList,
+                    getString(R.string.explain_perms),
+                    getString(R.string.ok),
+                    getString(R.string.cancel),
+                )
+            }
+            .onForwardToSettings { scope, deniedList ->
+                scope.showForwardToSettingsDialog(
+                    deniedList,
+                    getString(R.string.manual_perms),
+                    getString(R.string.ok),
+                    getString(R.string.cancel),
+                )
+            }
+            .request { allGranted, _, _ ->
+                if(!allGranted) {
+                    preferences.edit().apply {
+	                putBoolean(BLE_ENABLED, false)
+	                commit()
+	            }
+                }
+            }
+    }
+
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
         setContentView(R.layout.activity_main)
@@ -65,6 +108,7 @@ class MainActivity : AppCompatActivity() {
         enabledSwitch.setOnCheckedChangeListener { _, isChecked ->
             when (isChecked) {
                 true -> {
+                    checkBLEPermissions()
                     val vpnIntent = VpnService.prepare(this)
                     if (vpnIntent != null) {
                         startVpnActivity.launch(vpnIntent)

app/src/main/java/eu/neilalexander/yggdrasil/PacketTunnelProvider.kt

@@ -9,10 +9,14 @@ import android.util.Log
 import androidx.localbroadcastmanager.content.LocalBroadcastManager
 import androidx.preference.PreferenceManager
 import eu.neilalexander.yggdrasil.YggStateReceiver.Companion.YGG_STATE_INTENT
+import org.akselrod.blemesh.BLEService
 import mobile.Yggdrasil
 import org.json.JSONArray
 import java.io.FileInputStream
 import java.io.FileOutputStream
+import java.io.InputStream
+import java.io.OutputStream
+import java.net.Socket
 import java.util.concurrent.atomic.AtomicBoolean
 import kotlin.concurrent.thread
 
@@ -43,6 +47,8 @@ open class PacketTunnelProvider: VpnService() {
     private var readerStream: FileInputStream? = null
     private var writerStream: FileOutputStream? = null
 
+    private var bleService: BLEService? = null
+
     override fun onCreate() {
         super.onCreate()
         config = ConfigurationProxy(applicationContext)
@@ -175,13 +181,23 @@ open class PacketTunnelProvider: VpnService() {
         intent = Intent(YGG_STATE_INTENT)
         intent.putExtra("state", STATE_ENABLED)
         LocalBroadcastManager.getInstance(this).sendBroadcast(intent)
+
+	if (preferences.getBoolean(BLE_ENABLED, (Build.VERSION.SDK_INT >= Build.VERSION_CODES.S))) {
+            val publicKey = config.getJSON().getString("PublicKey")
+	    val codedPhy = preferences.getBoolean(CODED_PHY_ENABLED, false)
+	    bleService = BLEService(this.baseContext, publicKey, codedPhy, ::peerConnect)
+	    bleService?.start()
+	}
     }
 
     private fun stop() {
         if (!started.compareAndSet(true, false)) {
             return
         }
 
+        bleService?.stop()
+	bleService = null
+
         yggdrasil.stop()
 
         readerStream?.let {
@@ -336,4 +352,17 @@ open class PacketTunnelProvider: VpnService() {
             readerStream = null
         }
     }
+
+    private fun peerConnect(): Pair<InputStream, OutputStream>? {
+        var socket: Socket?
+        try {
+            socket = Socket("127.0.0.1", 9004)
+        } catch (e: Exception) {
+            Log.e(TAG, "Couldn't open peer socket: $e")
+	    return null
+        }
+        return Pair(socket.inputStream, socket.outputStream)
+    }
+
+
 }

app/src/main/java/eu/neilalexander/yggdrasil/PeersActivity.kt

@@ -7,11 +7,13 @@ import android.content.Intent
 import android.content.IntentFilter
 import androidx.appcompat.app.AppCompatActivity
 import android.os.Bundle
+import android.os.Build
 import android.view.ContextThemeWrapper
 import android.view.LayoutInflater
 import android.view.View
 import android.widget.*
 import androidx.localbroadcastmanager.content.LocalBroadcastManager
+import androidx.preference.PreferenceManager
 import com.google.android.material.textfield.TextInputEditText
 import org.json.JSONArray
 import org.json.JSONObject
@@ -27,6 +29,8 @@ class PeersActivity : AppCompatActivity() {
     private lateinit var configuredTableLabel: TextView
     private lateinit var multicastListenSwitch: Switch
     private lateinit var multicastBeaconSwitch: Switch
+    private lateinit var enableBLESwitch: Switch
+    private lateinit var enableCodedPHYSwitch: Switch
     private lateinit var addPeerButton: ImageButton
 
     override fun onCreate(savedInstanceState: Bundle?) {
@@ -51,9 +55,29 @@ class PeersActivity : AppCompatActivity() {
         multicastBeaconSwitch.setOnCheckedChangeListener { button, _ ->
             config.multicastBeacon = button.isChecked
         }
+
+        val preferences = PreferenceManager.getDefaultSharedPreferences(this.baseContext)
+
+	enableBLESwitch = findViewById(R.id.enableBLE)
+	enableBLESwitch.setOnCheckedChangeListener { button, _ ->
+            preferences.edit().apply {
+	        putBoolean(BLE_ENABLED, button.isChecked)
+	        commit()
+	    }
+	}
+	enableCodedPHYSwitch = findViewById(R.id.enableCodedPHY)
+	enableCodedPHYSwitch.setOnCheckedChangeListener { button, _ ->
+            preferences.edit().apply {
+	        putBoolean(CODED_PHY_ENABLED, button.isChecked)
+	        commit()
+	    }
+	}
+
         multicastListenSwitch.isChecked = config.multicastListen
         multicastBeaconSwitch.isChecked = config.multicastBeacon
-
+	enableBLESwitch.isChecked = preferences.getBoolean(BLE_ENABLED, (Build.VERSION.SDK_INT >= Build.VERSION_CODES.S))
+	enableCodedPHYSwitch.isChecked = preferences.getBoolean(CODED_PHY_ENABLED, false)
+
         val multicastBeaconPanel = findViewById<TableRow>(R.id.enableMulticastBeaconPanel)
         multicastBeaconPanel.setOnClickListener {
             multicastBeaconSwitch.toggle()
@@ -63,6 +87,19 @@ class PeersActivity : AppCompatActivity() {
             multicastListenSwitch.toggle()
         }
 
+        val enableBLEPanel = findViewById<TableRow>(R.id.enableBLEPanel)
+        val enableCodedPHYPanel = findViewById<TableRow>(R.id.enableCodedPHYPanel)
+
+        enableBLEPanel.isEnabled = (Build.VERSION.SDK_INT >= Build.VERSION_CODES.S)
+        enableCodedPHYPanel.isEnabled = (Build.VERSION.SDK_INT >= Build.VERSION_CODES.S)
+
+        enableBLEPanel.setOnClickListener {
+            enableBLESwitch.toggle()
+        }
+        enableCodedPHYPanel.setOnClickListener {
+            enableCodedPHYSwitch.toggle()
+        }
+
         addPeerButton = findViewById(R.id.addPeerButton)
         addPeerButton.setOnClickListener {
             val view = inflater.inflate(R.layout.dialog_addpeer, null)
@@ -181,4 +218,4 @@ class PeersActivity : AppCompatActivity() {
             }
         }
     }
-}
+}

app/src/main/res/layout/activity_peers.xml

@@ -217,6 +217,50 @@
 
                         </TableRow>
 
+                        <TableRow
+                            android:id="@+id/enableBLEPanel"
+                            style="@style/SelectableSwitchItemStyle">
+
+                            <TextView
+                                android:layout_width="wrap_content"
+                                android:layout_height="wrap_content"
+                                android:text="@string/enable_ble"
+                                android:textColor="?attr/textDefault" />
+
+                            <Space
+                                android:layout_width="wrap_content"
+                                android:layout_height="wrap_content"
+                                android:layout_weight="2" />
+
+                            <Switch
+                                android:id="@+id/enableBLE"
+                                android:layout_width="wrap_content"
+                                android:layout_height="wrap_content" />
+
+                        </TableRow>
+
+                        <TableRow
+                            android:id="@+id/enableCodedPHYPanel"
+                            style="@style/SelectableSwitchItemStyle">
+
+                            <TextView
+                                android:layout_width="wrap_content"
+                                android:layout_height="wrap_content"
+                                android:text="@string/enable_coded_phy"
+                                android:textColor="?attr/textDefault" />
+
+                            <Space
+                                android:layout_width="wrap_content"
+                                android:layout_height="wrap_content"
+                                android:layout_weight="2" />
+
+                            <Switch
+                                android:id="@+id/enableCodedPHY"
+                                android:layout_width="wrap_content"
+                                android:layout_height="wrap_content" />
+
+                        </TableRow>
+
                     </TableLayout>
 
                     <TextView