Support toggling hotspots in app

This is a just-for-fun feature. It probably doesn't work.

README.md

@@ -45,6 +45,11 @@ You'll have to use WPS for now to make the repeater switch to 2.4GHz.
 
 ### [IPv6 tethering?](https://github.com/Mygod/VPNHotspot/issues/6)
 
+### Missing `android.permission.MANAGE_USB` permission?
+
+Toggling USB tethering only works if you install this app as a system app (`/system/priv-app`).
+Alternatively, use the toggle in your system settings instead.
+
 ### No root?
 
 Without root, you can only:

mobile/build.gradle

@@ -34,6 +34,7 @@ dependencies {
     implementation "com.android.support:design:$supportLibraryVersion"
     implementation "com.android.support:preference-v14:$supportLibraryVersion"
     implementation 'com.android.support.constraint:constraint-layout:1.1.0'
+    implementation 'com.linkedin.dexmaker:dexmaker-mockito:2.16.0'
     implementation "com.takisoft.fix:preference-v7:$takisoftFixVersion"
     implementation "org.jetbrains.kotlin:kotlin-stdlib-jre7:$kotlinVersion"
     testImplementation 'junit:junit:4.12'

mobile/proguard-rules.pro

@@ -20,3 +20,5 @@
 # If you keep the line number information, uncomment this to
 # hide the original source file name.
 #-renamesourcefileattribute SourceFile
+-dontwarn org.mockito.**
+-dontwarn org.objenesis.instantiator.**

mobile/src/main/AndroidManifest.xml

@@ -1,7 +1,11 @@
 <?xml version="1.0" encoding="utf-8"?>
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
+          xmlns:tools="http://schemas.android.com/tools"
           package="be.mygod.vpnhotspot">
 
+    <uses-feature
+        android:name="android.bluetooth"
+        android:required="false"/>
     <uses-feature
         android:name="android.hardware.touchscreen"
         android:required="false"/>
@@ -14,8 +18,14 @@
 
     <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
     <uses-permission android:name="android.permission.ACCESS_WIFI_STATE"/>
+    <uses-permission android:name="android.permission.BLUETOOTH"/>
     <uses-permission android:name="android.permission.CHANGE_WIFI_STATE"/>
     <uses-permission android:name="android.permission.INTERNET"/>
+    <uses-permission android:name="android.permission.MANAGE_USB"
+                     tools:ignore="ProtectedPermissions"/>
+    <uses-permission android:name="android.permission.TETHER_PRIVILEGE"/>
+    <uses-permission android:name="android.permission.WRITE_SETTINGS"
+                     tools:ignore="ProtectedPermissions"/>
 
     <application
         android:name=".App"

mobile/src/main/java/be/mygod/vpnhotspot/App.kt

@@ -5,6 +5,7 @@ import android.app.Application
 import android.content.Context
 import android.content.SharedPreferences
 import android.content.res.Configuration
+import android.net.ConnectivityManager
 import android.os.Build
 import android.os.Handler
 import android.preference.PreferenceManager
@@ -37,6 +38,7 @@ class App : Application() {
     lateinit var deviceContext: Context
     val handler = Handler()
     val pref: SharedPreferences by lazy { PreferenceManager.getDefaultSharedPreferences(deviceContext) }
+    val connectivity by lazy { getSystemService(Context.CONNECTIVITY_SERVICE) as ConnectivityManager }
 
     fun toast(@StringRes resId: Int) = handler.post { Toast.makeText(this, resId, Toast.LENGTH_SHORT).show() }
 }

mobile/src/main/java/be/mygod/vpnhotspot/RepeaterFragment.kt

@@ -28,7 +28,7 @@ import be.mygod.vpnhotspot.databinding.FragmentRepeaterBinding
 import be.mygod.vpnhotspot.databinding.ListitemClientBinding
 import be.mygod.vpnhotspot.net.IpNeighbour
 import be.mygod.vpnhotspot.net.IpNeighbourMonitor
-import be.mygod.vpnhotspot.net.ConnectivityManagerHelper
+import be.mygod.vpnhotspot.net.TetheringManager
 import be.mygod.vpnhotspot.net.TetherType
 import java.net.NetworkInterface
 import java.net.SocketException
@@ -160,7 +160,7 @@ class RepeaterFragment : Fragment(), ServiceConnection, Toolbar.OnMenuItemClickL
     private var p2pInterface: String? = null
     private var tetheredInterfaces = emptySet<String>()
     private val receiver = broadcastReceiver { _, intent ->
-        tetheredInterfaces = ConnectivityManagerHelper.getTetheredIfaces(intent.extras).toSet()
+        tetheredInterfaces = TetheringManager.getTetheredIfaces(intent.extras).toSet()
         adapter.recreate()
     }
 
@@ -185,7 +185,7 @@ class RepeaterFragment : Fragment(), ServiceConnection, Toolbar.OnMenuItemClickL
         val context = requireContext()
         context.bindService(Intent(context, RepeaterService::class.java), this, Context.BIND_AUTO_CREATE)
         IpNeighbourMonitor.registerCallback(this)
-        context.registerReceiver(receiver, intentFilter(ConnectivityManagerHelper.ACTION_TETHER_STATE_CHANGED))
+        context.registerReceiver(receiver, intentFilter(TetheringManager.ACTION_TETHER_STATE_CHANGED))
     }
 
     override fun onStop() {

mobile/src/main/java/be/mygod/vpnhotspot/TetheringFragment.kt

@@ -1,10 +1,18 @@
 package be.mygod.vpnhotspot
 
+import android.annotation.SuppressLint
+import android.bluetooth.BluetoothAdapter
+import android.bluetooth.BluetoothProfile
 import android.content.*
 import android.databinding.BaseObservable
+import android.databinding.Bindable
 import android.databinding.DataBindingUtil
+import android.net.Uri
+import android.os.Build
 import android.os.Bundle
 import android.os.IBinder
+import android.provider.Settings
+import android.support.annotation.RequiresApi
 import android.support.v4.app.Fragment
 import android.support.v4.content.ContextCompat
 import android.support.v7.recyclerview.extensions.ListAdapter
@@ -15,10 +23,15 @@ import android.support.v7.widget.RecyclerView
 import android.view.LayoutInflater
 import android.view.View
 import android.view.ViewGroup
+import android.widget.Toast
+import be.mygod.vpnhotspot.App.Companion.app
 import be.mygod.vpnhotspot.databinding.FragmentTetheringBinding
 import be.mygod.vpnhotspot.databinding.ListitemInterfaceBinding
-import be.mygod.vpnhotspot.net.ConnectivityManagerHelper
+import be.mygod.vpnhotspot.databinding.ListitemManageTetherBinding
 import be.mygod.vpnhotspot.net.TetherType
+import be.mygod.vpnhotspot.net.TetheringManager
+import be.mygod.vpnhotspot.net.WifiApManager
+import java.lang.reflect.InvocationTargetException
 import java.net.NetworkInterface
 import java.net.SocketException
 import java.util.*
@@ -27,6 +40,19 @@ class TetheringFragment : Fragment(), ServiceConnection {
     companion object {
         private const val VIEW_TYPE_INTERFACE = 0
         private const val VIEW_TYPE_MANAGE = 1
+        private const val VIEW_TYPE_WIFI = 2
+        private const val VIEW_TYPE_USB = 3
+        private const val VIEW_TYPE_BLUETOOTH = 4
+        private const val VIEW_TYPE_WIFI_LEGACY = 5
+
+        /**
+         * PAN Profile
+         * From BluetoothProfile.java.
+         */
+        private const val PAN = 5
+        private val isTetheringOn by lazy @SuppressLint("PrivateApi") {
+            Class.forName("android.bluetooth.BluetoothPan").getDeclaredMethod("isTetheringOn")
+        }
     }
 
     inner class Data(val iface: TetheredInterface) : BaseObservable() {
@@ -62,6 +88,105 @@ class TetheringFragment : Fragment(), ServiceConnection {
                     .setClassName("com.android.settings", "com.android.settings.TetherSettings"))
         }
     }
+    private inner class ManageItemHolder(binding: ListitemManageTetherBinding, private val type: Int)
+        : RecyclerView.ViewHolder(binding.root), View.OnClickListener, TetheringManager.OnStartTetheringCallback {
+        val tetherType = when (type) {
+            VIEW_TYPE_WIFI, VIEW_TYPE_WIFI_LEGACY -> TetherType.WIFI
+            VIEW_TYPE_USB -> TetherType.USB
+            VIEW_TYPE_BLUETOOTH -> TetherType.BLUETOOTH
+            else -> TetherType.NONE
+        }
+        init {
+            itemView.setOnClickListener(this)
+            binding.icon = tetherType.icon
+            binding.title = getString(when (type) {
+                VIEW_TYPE_USB -> R.string.tethering_manage_usb
+                VIEW_TYPE_WIFI -> R.string.tethering_manage_wifi
+                VIEW_TYPE_WIFI_LEGACY -> R.string.tethering_manage_wifi_legacy
+                VIEW_TYPE_BLUETOOTH -> R.string.tethering_manage_bluetooth
+                else -> throw IllegalStateException()
+            })
+            binding.tetherListener = tetherListener
+            binding.type = tetherType
+        }
+
+        override fun onClick(v: View?) {
+            val context = requireContext()
+            if (Build.VERSION.SDK_INT >= 23 && !Settings.System.canWrite(context)) {
+                startActivity(Intent(Settings.ACTION_MANAGE_WRITE_SETTINGS,
+                        Uri.parse("package:${context.packageName}")))
+                return
+            }
+            val started = tetherListener.isStarted(tetherType)
+            try {
+                when (type) {
+                    VIEW_TYPE_WIFI -> @RequiresApi(24) {
+                        if (started) TetheringManager.stop(TetheringManager.TETHERING_WIFI)
+                        else TetheringManager.start(TetheringManager.TETHERING_WIFI, true, this)
+                    }
+                    VIEW_TYPE_USB -> @RequiresApi(24) {
+                        if (started) TetheringManager.stop(TetheringManager.TETHERING_USB)
+                        else TetheringManager.start(TetheringManager.TETHERING_USB, true, this)
+                    }
+                    VIEW_TYPE_BLUETOOTH -> @RequiresApi(24) {
+                        if (started) {
+                            TetheringManager.stop(TetheringManager.TETHERING_BLUETOOTH)
+                            Thread.sleep(1)         // give others a room to breathe
+                            onTetheringStarted()    // force flush state
+                        } else TetheringManager.start(TetheringManager.TETHERING_BLUETOOTH, true, this)
+                    }
+                    VIEW_TYPE_WIFI_LEGACY -> @Suppress("DEPRECATION") {
+                        if (started) WifiApManager.stop() else WifiApManager.start()
+                    }
+                }
+            } catch (e: InvocationTargetException) {
+                e.printStackTrace()
+                var cause: Throwable? = e
+                while (cause != null) {
+                    cause = cause.cause
+                    if (cause != null && cause !is InvocationTargetException) {
+                        Toast.makeText(context, cause.message, Toast.LENGTH_LONG).show()
+                        break
+                    }
+                }
+            }
+        }
+
+        override fun onTetheringStarted() = tetherListener.notifyPropertyChanged(BR.enabledTypes)
+        override fun onTetheringFailed() {
+            app.handler.post {
+                Toast.makeText(requireContext(), "Android system has failed to start tethering.", Toast.LENGTH_SHORT).show()
+            }
+        }
+    }
+
+    class TetherListener : BaseObservable(), BluetoothProfile.ServiceListener {
+        var enabledTypes = emptySet<TetherType>()
+            @Bindable get
+            set(value) {
+                field = value
+                notifyPropertyChanged(BR.enabledTypes)
+            }
+        var pan: BluetoothProfile? = null
+
+        override fun onServiceDisconnected(profile: Int) {
+            pan = null
+        }
+        override fun onServiceConnected(profile: Int, proxy: BluetoothProfile) {
+            pan = proxy
+        }
+
+        /**
+         * Based on: https://android.googlesource.com/platform/packages/apps/Settings/+/78d5efd/src/com/android/settings/TetherSettings.java
+         */
+        fun isStarted(type: TetherType, enabledTypes: Set<TetherType> = this.enabledTypes): Boolean {
+            return if (type == TetherType.BLUETOOTH) {
+                val pan = pan
+                BluetoothAdapter.getDefaultAdapter()?.state == BluetoothAdapter.STATE_ON && pan != null &&
+                        isTetheringOn.invoke(pan) as Boolean
+            } else enabledTypes.contains(type)
+        }
+    }
     class TetheredInterface(val name: String, lookup: Map<String, NetworkInterface>) : Comparable<TetheredInterface> {
         val addresses = lookup[name]?.formatAddresses() ?: ""
 
@@ -91,17 +216,30 @@ class TetheringFragment : Fragment(), ServiceConnection {
                 e.printStackTrace()
                 emptyMap<String, NetworkInterface>()
             }
+            this@TetheringFragment.tetherListener.enabledTypes = data.map { TetherType.ofInterface(it) }.toSet()
             submitList(data.map { TetheredInterface(it, lookup) }.sorted())
         }
 
-        override fun getItemCount() = super.getItemCount() + 1
+        override fun getItemCount() = super.getItemCount() + when (Build.VERSION.SDK_INT) {
-        override fun getItemViewType(position: Int) =
+            in 0 until 24 -> 2
-                if (position == super.getItemCount()) VIEW_TYPE_MANAGE else VIEW_TYPE_INTERFACE
+            in 24..25 -> 5
+            else -> 4
+        }
+        override fun getItemViewType(position: Int) = when (position - super.getItemCount()) {
+            0 -> VIEW_TYPE_MANAGE
+            1 -> if (Build.VERSION.SDK_INT >= 24) VIEW_TYPE_USB else VIEW_TYPE_WIFI_LEGACY
+            2 -> VIEW_TYPE_WIFI
+            3 -> VIEW_TYPE_BLUETOOTH
+            4 -> VIEW_TYPE_WIFI_LEGACY
+            else -> VIEW_TYPE_INTERFACE
+        }
         override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): RecyclerView.ViewHolder {
             val inflater = LayoutInflater.from(parent.context)
             return when (viewType) {
                 VIEW_TYPE_INTERFACE -> InterfaceViewHolder(ListitemInterfaceBinding.inflate(inflater, parent, false))
                 VIEW_TYPE_MANAGE -> ManageViewHolder(inflater.inflate(R.layout.listitem_manage, parent, false))
+                VIEW_TYPE_WIFI, VIEW_TYPE_USB, VIEW_TYPE_BLUETOOTH, VIEW_TYPE_WIFI_LEGACY ->
+                    ManageItemHolder(ListitemManageTetherBinding.inflate(inflater, parent, false), viewType)
                 else -> throw IllegalArgumentException("Invalid view type")
             }
         }
@@ -112,11 +250,12 @@ class TetheringFragment : Fragment(), ServiceConnection {
         }
     }
 
+    private val tetherListener = TetherListener()
     private lateinit var binding: FragmentTetheringBinding
     private var binder: TetheringService.TetheringBinder? = null
     val adapter = TetheringAdapter()
     private val receiver = broadcastReceiver { _, intent ->
-        adapter.update(ConnectivityManagerHelper.getTetheredIfaces(intent.extras))
+        adapter.update(TetheringManager.getTetheredIfaces(intent.extras))
     }
 
     override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
@@ -124,13 +263,14 @@ class TetheringFragment : Fragment(), ServiceConnection {
         binding.interfaces.layoutManager = LinearLayoutManager(context, LinearLayoutManager.VERTICAL, false)
         binding.interfaces.itemAnimator = DefaultItemAnimator()
         binding.interfaces.adapter = adapter
+        BluetoothAdapter.getDefaultAdapter()?.getProfileProxy(requireContext(), tetherListener, PAN)
         return binding.root
     }
 
     override fun onStart() {
         super.onStart()
         val context = requireContext()
-        context.registerReceiver(receiver, intentFilter(ConnectivityManagerHelper.ACTION_TETHER_STATE_CHANGED))
+        context.registerReceiver(receiver, intentFilter(TetheringManager.ACTION_TETHER_STATE_CHANGED))
         context.bindService(Intent(context, TetheringService::class.java), this, Context.BIND_AUTO_CREATE)
     }
 
@@ -141,6 +281,11 @@ class TetheringFragment : Fragment(), ServiceConnection {
         super.onStop()
     }
 
+    override fun onDestroy() {
+        tetherListener.pan = null
+        super.onDestroy()
+    }
+
     override fun onServiceConnected(name: ComponentName?, service: IBinder?) {
         val binder = service as TetheringService.TetheringBinder
         this.binder = binder

mobile/src/main/java/be/mygod/vpnhotspot/TetheringService.kt

@@ -31,8 +31,8 @@ class TetheringService : Service(), VpnMonitor.Callback, IpNeighbourMonitor.Call
     private val receiver = broadcastReceiver { _, intent ->
         synchronized(routings) {
             when (intent.action) {
-                ConnectivityManagerHelper.ACTION_TETHER_STATE_CHANGED -> {
+                TetheringManager.ACTION_TETHER_STATE_CHANGED -> {
-                    val remove = routings.keys - ConnectivityManagerHelper.getTetheredIfaces(intent.extras)
+                    val remove = routings.keys - TetheringManager.getTetheredIfaces(intent.extras)
                     if (remove.isEmpty()) return@broadcastReceiver
                     val failed = remove.any { routings.remove(it)?.stop() == false }
                     if (failed) Toast.makeText(this, getText(R.string.noisy_su_failure), Toast.LENGTH_SHORT).show()
@@ -67,7 +67,7 @@ class TetheringService : Service(), VpnMonitor.Callback, IpNeighbourMonitor.Call
                 }
                 if (failed) Toast.makeText(this, getText(R.string.noisy_su_failure), Toast.LENGTH_SHORT).show()
             } else if (!receiverRegistered) {
-                registerReceiver(receiver, intentFilter(ConnectivityManagerHelper.ACTION_TETHER_STATE_CHANGED))
+                registerReceiver(receiver, intentFilter(TetheringManager.ACTION_TETHER_STATE_CHANGED))
                 LocalBroadcastManager.getInstance(this)
                         .registerReceiver(receiver, intentFilter(App.ACTION_CLEAN_ROUTINGS))
                 IpNeighbourMonitor.registerCallback(this)

mobile/src/main/java/be/mygod/vpnhotspot/net/ConnectivityManagerHelper.kt

@@ -1,26 +0,0 @@
-package be.mygod.vpnhotspot.net
-
-import android.os.Build
-import android.os.Bundle
-import android.support.annotation.RequiresApi
-
-/**
- * Hidden constants from ConnectivityManager and some helpers.
- */
-object ConnectivityManagerHelper {
-    /**
-     * This is a sticky broadcast since almost forever.
-     *
-     * https://android.googlesource.com/platform/frameworks/base.git/+/2a091d7aa0c174986387e5d56bf97a87fe075bdb%5E%21/services/java/com/android/server/connectivity/Tethering.java
-     */
-    const val ACTION_TETHER_STATE_CHANGED = "android.net.conn.TETHER_STATE_CHANGED"
-    private const val EXTRA_ACTIVE_TETHER_LEGACY = "activeArray"
-    @RequiresApi(26)
-    private const val EXTRA_ACTIVE_LOCAL_ONLY = "localOnlyArray"
-    @RequiresApi(26)
-    private const val EXTRA_ACTIVE_TETHER = "tetherArray"
-
-    fun getTetheredIfaces(extras: Bundle) = if (Build.VERSION.SDK_INT >= 26)
-        extras.getStringArrayList(EXTRA_ACTIVE_TETHER).toSet() + extras.getStringArrayList(EXTRA_ACTIVE_LOCAL_ONLY)
-    else extras.getStringArrayList(EXTRA_ACTIVE_TETHER_LEGACY).toSet()
-}

mobile/src/main/java/be/mygod/vpnhotspot/net/TetheringManager.kt

@@ -0,0 +1,131 @@
+package be.mygod.vpnhotspot.net
+
+import android.annotation.SuppressLint
+import android.net.ConnectivityManager
+import android.os.Build
+import android.os.Bundle
+import android.os.Handler
+import android.support.annotation.RequiresApi
+import android.util.Log
+import be.mygod.vpnhotspot.App.Companion.app
+import com.android.dx.stock.ProxyBuilder
+
+/**
+ * Heavily based on:
+ * https://github.com/aegis1980/WifiHotSpot
+ * https://android.googlesource.com/platform/frameworks/base.git/+/android-7.0.0_r1/core/java/android/net/ConnectivityManager.java
+ */
+object TetheringManager {
+    /**
+     * Callback for use with [.startTethering] to find out whether tethering succeeded.
+     */
+    interface OnStartTetheringCallback {
+        /**
+         * Called when tethering has been successfully started.
+         */
+        fun onTetheringStarted() { }
+
+        /**
+         * Called when starting tethering failed.
+         */
+        fun onTetheringFailed() { }
+    }
+
+    private const val TAG = "TetheringManager"
+
+    /**
+     * This is a sticky broadcast since almost forever.
+     *
+     * https://android.googlesource.com/platform/frameworks/base.git/+/2a091d7aa0c174986387e5d56bf97a87fe075bdb%5E%21/services/java/com/android/server/connectivity/Tethering.java
+     */
+    const val ACTION_TETHER_STATE_CHANGED = "android.net.conn.TETHER_STATE_CHANGED"
+    private const val EXTRA_ACTIVE_TETHER_LEGACY = "activeArray"
+    @RequiresApi(26)
+    private const val EXTRA_ACTIVE_LOCAL_ONLY = "localOnlyArray"
+    @RequiresApi(26)
+    private const val EXTRA_ACTIVE_TETHER = "tetherArray"
+
+    const val TETHERING_WIFI = 0
+    /**
+     * Requires MANAGE_USB permission, unfortunately.
+     *
+     * Source: https://android.googlesource.com/platform/frameworks/base/+/7ca5d3a/services/usb/java/com/android/server/usb/UsbService.java#389
+     */
+    const val TETHERING_USB = 1
+    /**
+     * Requires BLUETOOTH permission.
+     */
+    const val TETHERING_BLUETOOTH = 2
+
+    private val classOnStartTetheringCallback by lazy @SuppressLint("PrivateApi") {
+        Class.forName("android.net.ConnectivityManager\$OnStartTetheringCallback")
+    }
+    private val startTethering by lazy {
+        ConnectivityManager::class.java.getDeclaredMethod("startTethering",
+                Int::class.java, Boolean::class.java, classOnStartTetheringCallback, Handler::class.java)
+    }
+    private val stopTethering by lazy {
+        ConnectivityManager::class.java.getDeclaredMethod("stopTethering", Int::class.java)
+    }
+
+    /**
+     * Runs tether provisioning for the given type if needed and then starts tethering if
+     * the check succeeds. If no carrier provisioning is required for tethering, tethering is
+     * enabled immediately. If provisioning fails, tethering will not be enabled. It also
+     * schedules tether provisioning re-checks if appropriate.
+     *
+     * @param type The type of tethering to start. Must be one of
+     *         {@link ConnectivityManager.TETHERING_WIFI},
+     *         {@link ConnectivityManager.TETHERING_USB}, or
+     *         {@link ConnectivityManager.TETHERING_BLUETOOTH}.
+     * @param showProvisioningUi a boolean indicating to show the provisioning app UI if there
+     *         is one. This should be true the first time this function is called and also any time
+     *         the user can see this UI. It gives users information from their carrier about the
+     *         check failing and how they can sign up for tethering if possible.
+     * @param callback an {@link OnStartTetheringCallback} which will be called to notify the caller
+     *         of the result of trying to tether.
+     * @param handler {@link Handler} to specify the thread upon which the callback will be invoked.
+     */
+    @RequiresApi(24)
+    fun start(type: Int, showProvisioningUi: Boolean, callback: OnStartTetheringCallback, handler: Handler? = null) {
+        val proxy = ProxyBuilder.forClass(classOnStartTetheringCallback)
+                .dexCache(app.cacheDir)
+                .handler { proxy, method, args ->
+                    if (args.isNotEmpty()) Log.w(TAG, "Unexpected args for ${method.name}: $args")
+                    when (method.name) {
+                        "onTetheringStarted" -> {
+                            callback.onTetheringStarted()
+                            null
+                        }
+                        "onTetheringFailed" -> {
+                            callback.onTetheringFailed()
+                            null
+                        }
+                        else -> {
+                            Log.w(TAG, "Unexpected method, calling super: $method")
+                            ProxyBuilder.callSuper(proxy, method, args)
+                        }
+                    }
+                }
+                .build()
+        startTethering.invoke(app.connectivity, type, showProvisioningUi, proxy, handler)
+    }
+
+    /**
+     * Stops tethering for the given type. Also cancels any provisioning rechecks for that type if
+     * applicable.
+     *
+     * @param type The type of tethering to stop. Must be one of
+     *         {@link ConnectivityManager.TETHERING_WIFI},
+     *         {@link ConnectivityManager.TETHERING_USB}, or
+     *         {@link ConnectivityManager.TETHERING_BLUETOOTH}.
+     */
+    @RequiresApi(24)
+    fun stop(type: Int) {
+        stopTethering.invoke(app.connectivity, type)
+    }
+
+    fun getTetheredIfaces(extras: Bundle) = if (Build.VERSION.SDK_INT >= 26)
+        extras.getStringArrayList(EXTRA_ACTIVE_TETHER).toSet() + extras.getStringArrayList(EXTRA_ACTIVE_LOCAL_ONLY)
+    else extras.getStringArrayList(EXTRA_ACTIVE_TETHER_LEGACY).toSet()
+}

mobile/src/main/java/be/mygod/vpnhotspot/net/VpnMonitor.kt

@@ -17,7 +17,6 @@ object VpnMonitor : ConnectivityManager.NetworkCallback() {
 
     private const val TAG = "VpnMonitor"
 
-    private val manager = app.getSystemService(Context.CONNECTIVITY_SERVICE) as ConnectivityManager
     private val request = NetworkRequest.Builder()
             .addTransportType(NetworkCapabilities.TRANSPORT_VPN)
             .removeCapability(NetworkCapabilities.NET_CAPABILITY_NOT_VPN)
@@ -31,7 +30,7 @@ object VpnMonitor : ConnectivityManager.NetworkCallback() {
     private val available = HashMap<Network, String>()
     private var currentNetwork: Network? = null
     override fun onAvailable(network: Network) {
-        val properties = manager.getLinkProperties(network)
+        val properties = app.connectivity.getLinkProperties(network)
         val ifname = properties?.interfaceName ?: return
         synchronized(this) {
             if (available.put(network, ifname) != null) return
@@ -55,7 +54,7 @@ object VpnMonitor : ConnectivityManager.NetworkCallback() {
         while (available.isNotEmpty()) {
             val next = available.entries.first()
             currentNetwork = next.key
-            val properties = manager.getLinkProperties(next.key)
+            val properties = app.connectivity.getLinkProperties(next.key)
             if (properties != null) {
                 debugLog(TAG, "Switching to ${next.value} as VPN interface")
                 callbacks.forEach { it.onAvailable(next.value, properties.dnsServers) }
@@ -70,16 +69,17 @@ object VpnMonitor : ConnectivityManager.NetworkCallback() {
         if (synchronized(this) {
                     if (!callbacks.add(callback)) return
                     if (!registered) {
-                        manager.registerNetworkCallback(request, this)
+                        app.connectivity.registerNetworkCallback(request, this)
                         registered = true
-                        manager.allNetworks.all {
+                        app.connectivity.allNetworks.all {
-                            val cap = manager.getNetworkCapabilities(it)
+                            val cap = app.connectivity.getNetworkCapabilities(it)
                             !cap.hasTransport(NetworkCapabilities.TRANSPORT_VPN) ||
                                     cap.hasCapability(NetworkCapabilities.NET_CAPABILITY_NOT_VPN)
                         }
                     } else if (available.isEmpty()) true else {
                         available.forEach {
-                            callback.onAvailable(it.value, manager.getLinkProperties(it.key)?.dnsServers ?: emptyList())
+                            callback.onAvailable(it.value,
+                                    app.connectivity.getLinkProperties(it.key)?.dnsServers ?: emptyList())
                         }
                         false
                     }
@@ -87,7 +87,7 @@ object VpnMonitor : ConnectivityManager.NetworkCallback() {
     }
     fun unregisterCallback(callback: Callback) = synchronized(this) {
         if (!callbacks.remove(callback) || callbacks.isNotEmpty() || !registered) return
-        manager.unregisterNetworkCallback(this)
+        app.connectivity.unregisterNetworkCallback(this)
         registered = false
         available.clear()
         currentNetwork = null

mobile/src/main/java/be/mygod/vpnhotspot/net/WifiApManager.kt

@@ -0,0 +1,34 @@
+package be.mygod.vpnhotspot.net
+
+import android.content.Context
+import android.net.wifi.WifiConfiguration
+import android.net.wifi.WifiManager
+import be.mygod.vpnhotspot.App.Companion.app
+
+@Deprecated("No longer usable since API 26.")
+object WifiApManager {
+    private val wifi = app.getSystemService(Context.WIFI_SERVICE) as WifiManager
+    private val setWifiApEnabled = WifiManager::class.java.getDeclaredMethod("setWifiApEnabled",
+            WifiConfiguration::class.java, Boolean::class.java)
+    /**
+     * Start AccessPoint mode with the specified
+     * configuration. If the radio is already running in
+     * AP mode, update the new configuration
+     * Note that starting in access point mode disables station
+     * mode operation
+     * @param wifiConfig SSID, security and channel details as
+     *        part of WifiConfiguration
+     * @return {@code true} if the operation succeeds, {@code false} otherwise
+     */
+    private fun WifiManager.setWifiApEnabled(wifiConfig: WifiConfiguration?, enabled: Boolean) =
+            setWifiApEnabled.invoke(this, wifiConfig, enabled) as Boolean
+
+    fun start(wifiConfig: WifiConfiguration? = null) {
+        wifi.isWifiEnabled = false
+        wifi.setWifiApEnabled(wifiConfig, true)
+    }
+    fun stop() {
+        wifi.setWifiApEnabled(null, false)
+        wifi.isWifiEnabled = true
+    }
+}

mobile/src/main/res/layout/listitem_manage_tether.xml

@@ -0,0 +1,62 @@
+<?xml version="1.0" encoding="utf-8"?>
+<layout
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools">
+    <data>
+        <import type="be.mygod.vpnhotspot.TetheringFragment"/>
+        <variable
+            name="icon"
+            type="Integer"/>
+        <variable
+            name="title"
+            type="String"/>
+        <variable
+            name="tetherListener"
+            type="TetheringFragment.TetherListener"/>
+        <variable
+            name="type"
+            type="be.mygod.vpnhotspot.net.TetherType"/>
+    </data>
+    <LinearLayout
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:background="?android:attr/selectableItemBackground"
+        android:focusable="true"
+        android:padding="16dp"
+        android:paddingStart="56dp"
+        tools:ignore="RtlSymmetry">
+
+        <ImageView
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_gravity="center_vertical"
+            android:src="@{safeUnbox(icon)}"
+            android:tint="?android:attr/textColorPrimary"
+            tools:src="@drawable/ic_device_network_wifi"/>
+
+        <Space
+            android:layout_width="16dp"
+            android:layout_height="0dp"/>
+
+        <TextView
+            android:layout_width="0dp"
+            android:layout_height="wrap_content"
+            android:layout_weight="1"
+            android:layout_gravity="center_vertical"
+            android:text="@{title}"
+            android:textAppearance="@style/TextAppearance.AppCompat.Subhead"
+            tools:text="@string/tethering_manage_wifi"/>
+
+        <Switch
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_gravity="center_vertical"
+            android:checked="@{tetherListener.isStarted(type, tetherListener.enabledTypes)}"
+            android:clickable="false"
+            android:ellipsize="end"
+            android:focusable="false"
+            android:focusableInTouchMode="false"
+            android:gravity="center_vertical"/>
+
+    </LinearLayout>
+</layout>

mobile/src/main/res/values-zh-rCN/strings.xml

@@ -21,18 +21,30 @@
     <string name="repeater_reset_credentials_failure">重置凭据失败（原因：%s）</string>
 
     <string name="repeater_inactive">未打开</string>
-    <string name="repeater_p2p_unavailable">Wi-Fi 直连不可用</string>
+    <string name="repeater_p2p_unavailable">Wi\u2011Fi 直连不可用</string>
     <string name="repeater_create_group_failure">创建 P2P 群组失败（原因：%s）</string>
     <string name="repeater_remove_group_failure">关闭已有 P2P 群组失败（原因：%s）</string>
     <string name="repeater_remove_old_group_failure">关闭 P2P 群组失败（原因：%s）</string>
 
     <string name="repeater_failure_reason_error">内部异常</string>
-    <string name="repeater_failure_reason_p2p_unsupported">设备不支持 Wi-Fi 直连</string>
+    <string name="repeater_failure_reason_p2p_unsupported">设备不支持 Wi\u2011Fi 直连</string>
     <string name="repeater_failure_reason_busy">系统忙</string>
     <string name="repeater_failure_reason_no_service_requests">未添加服务请求</string>
     <string name="repeater_failure_reason_unknown">未知 #%d</string>
 
     <string name="tethering_manage">管理…</string>
+    <!--
+     Values copied from:
+        * https://android.googlesource.com/platform/packages/apps/Settings/+/7686ef8/res/xml/tether_prefs.xml
+        * https://android.googlesource.com/platform/packages/apps/Settings/+/b63de87/res/values-zh-rCN/strings.xml
+        * @string/usb_tethering_button_text
+        * @string/wifi_hotspot_checkbox_text
+        * @string/bluetooth_tether_checkbox_text
+      -->
+    <string name="tethering_manage_usb">USB 网络共享</string>
+    <string name="tethering_manage_wifi">WLAN 热点</string>
+    <string name="tethering_manage_wifi_legacy">WLAN 热点 (旧 API)</string>
+    <string name="tethering_manage_bluetooth">蓝牙网络共享</string>
 
     <string name="connected_devices">已连接设备</string>
     <string name="connected_state_incomplete">%s (正在连接)</string>

mobile/src/main/res/values/strings.xml

@@ -23,18 +23,30 @@
     <string name="repeater_reset_credentials_failure">Failed to reset credentials (reason: %s)</string>
 
     <string name="repeater_inactive">Service inactive</string>
-    <string name="repeater_p2p_unavailable">Wi-Fi direct unavailable</string>
+    <string name="repeater_p2p_unavailable">Wi\u2011Fi direct unavailable</string>
     <string name="repeater_create_group_failure">Failed to create P2P group (reason: %s)</string>
     <string name="repeater_remove_group_failure">Failed to remove P2P group (reason: %s)</string>
     <string name="repeater_remove_old_group_failure">Failed to remove old P2P group (reason: %s)</string>
 
     <string name="repeater_failure_reason_error">internal error</string>
-    <string name="repeater_failure_reason_p2p_unsupported">Wi-Fi direct unsupported</string>
+    <string name="repeater_failure_reason_p2p_unsupported">Wi\u2011Fi direct unsupported</string>
     <string name="repeater_failure_reason_busy">framework is busy</string>
     <string name="repeater_failure_reason_no_service_requests">no service requests added</string>
     <string name="repeater_failure_reason_unknown">unknown #%d</string>
 
     <string name="tethering_manage">Manage…</string>
+    <!--
+     Values copied from:
+        * https://android.googlesource.com/platform/packages/apps/Settings/+/7686ef8/res/xml/tether_prefs.xml
+        * https://android.googlesource.com/platform/packages/apps/Settings/+/e5ed810/res/values/strings.xml
+        * @string/usb_tethering_button_text
+        * @string/wifi_hotspot_checkbox_text
+        * @string/bluetooth_tether_checkbox_text
+      -->
+    <string name="tethering_manage_usb">USB tethering</string>
+    <string name="tethering_manage_wifi">Wi\u2011Fi hotspot</string>
+    <string name="tethering_manage_wifi_legacy">Wi\u2011Fi hotspot (legacy)</string>
+    <string name="tethering_manage_bluetooth">Bluetooth tethering</string>
 
     <string name="connected_devices">Connected devices</string>
     <string name="connected_state_incomplete">%s (connecting)</string>