Fix connected devices

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

@@ -0,0 +1,20 @@
+package be.mygod.vpnhotspot
+
+import java.io.File
+
+class ArpCache(downstream: String) : HashMap<String, String>() {
+    companion object {
+        private val spaces = " +".toPattern()
+        private val mac = "^([0-9a-f]{2}:){5}[0-9a-f]{2}$".toPattern()
+    }
+
+    init {
+        File("/proc/net/arp").bufferedReader().useLines {
+            for (line in it) {
+                val parts = line.split(spaces)
+                // IP address       HW type     Flags       HW address            Mask     Device
+                if (parts.size >= 6 && parts[5] == downstream && mac.matcher(parts[3]).matches()) put(parts[3], parts[0])
+            }
+        }
+    }
+}

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

@@ -13,6 +13,7 @@ import android.support.v4.app.NotificationCompat
 import android.support.v4.content.ContextCompat
 import android.util.Log
 import android.widget.Toast
+import java.net.InetAddress
 
 class HotspotService : Service(), WifiP2pManager.ChannelListener {
     companion object {
@@ -46,7 +47,9 @@ class HotspotService : Service(), WifiP2pManager.ChannelListener {
     private lateinit var p2pManager: WifiP2pManager
     private lateinit var channel: WifiP2pManager.Channel
     lateinit var group: WifiP2pGroup
-    lateinit var clients: MutableCollection<WifiP2pDevice>
+        private set
+    var hostAddress: InetAddress? = null
+        private set
     private val binder = HotspotBinder()
     private var receiverRegistered = false
     private val receiver: BroadcastReceiver = object : BroadcastReceiver() {
@@ -55,14 +58,11 @@ class HotspotService : Service(), WifiP2pManager.ChannelListener {
                 WifiP2pManager.WIFI_P2P_STATE_CHANGED_ACTION ->
                     if (intent.getIntExtra(WifiP2pManager.EXTRA_WIFI_STATE, 0) ==
                             WifiP2pManager.WIFI_P2P_STATE_DISABLED) clean() // group may be enabled by other apps
-                WifiP2pManager.WIFI_P2P_PEERS_CHANGED_ACTION ->{
-                    clients = intent.getParcelableExtra<WifiP2pDeviceList>(WifiP2pManager.EXTRA_P2P_DEVICE_LIST).deviceList
-                    binder.data?.onClientsChanged()
-                }
                 WifiP2pManager.WIFI_P2P_CONNECTION_CHANGED_ACTION -> {
                     val info = intent.getParcelableExtra<WifiP2pInfo>(WifiP2pManager.EXTRA_WIFI_P2P_INFO)
                     val net = intent.getParcelableExtra<NetworkInfo>(WifiP2pManager.EXTRA_NETWORK_INFO)
                     val group = intent.getParcelableExtra<WifiP2pGroup>(WifiP2pManager.EXTRA_WIFI_P2P_GROUP)
+                    hostAddress = info.groupOwnerAddress
                     val downstream = group.`interface`
                     if (net.isConnected && downstream != null && this@HotspotService.downstream == null) {
                         this@HotspotService.downstream = downstream
@@ -80,7 +80,6 @@ class HotspotService : Service(), WifiP2pManager.ChannelListener {
                             doStart(group)
                         } else startFailure("Something went wrong, please check logcat.")
                     }
-                    group.`interface`
                     binder.data?.onGroupChanged()
                     Log.d(TAG, "${intent.action}: $info, $net, $group")
                 }
@@ -93,7 +92,8 @@ class HotspotService : Service(), WifiP2pManager.ChannelListener {
     }
 
     // TODO: do something to these hardcoded strings
-    private var downstream: String? = null
+    var downstream: String? = null
+        private set
     private val upstream = "tun0"
     private val route = "192.168.49.0/24"
     private val dns = "8.8.8.8:53"
@@ -122,7 +122,6 @@ class HotspotService : Service(), WifiP2pManager.ChannelListener {
         if (!receiverRegistered) {
             registerReceiver(receiver, createIntentFilter(
                     WifiP2pManager.WIFI_P2P_STATE_CHANGED_ACTION,
-                    WifiP2pManager.WIFI_P2P_PEERS_CHANGED_ACTION,
                     WifiP2pManager.WIFI_P2P_CONNECTION_CHANGED_ACTION,
                     WifiP2pManager.WIFI_P2P_THIS_DEVICE_CHANGED_ACTION))
             receiverRegistered = true
@@ -157,7 +156,6 @@ class HotspotService : Service(), WifiP2pManager.ChannelListener {
     })
     private fun doStart(group: WifiP2pGroup) {
         this.group = group
-        clients = group.clientList
         status = Status.ACTIVE
         startForeground(1, NotificationCompat.Builder(this@HotspotService, CHANNEL)
                 .setWhen(0)

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

@@ -47,31 +47,31 @@ class MainActivity : AppCompatActivity(), ServiceConnection {
         val running get() = binder?.status == HotspotService.Status.ACTIVE
         val ssid: String @Bindable get() = if (running) binder!!.service.group.networkName else ""
         val password: String @Bindable get() = if (running) binder!!.service.group.passphrase else ""
-        val clients @Bindable get() = if (running) binder!!.service.clients else null
 
         fun onStatusChanged() {
             notifyPropertyChanged(BR.switchEnabled)
             notifyPropertyChanged(BR.serviceStarted)
             onGroupChanged()
-            onClientsChanged()
         }
         fun onGroupChanged() {
             notifyPropertyChanged(BR.ssid)
             notifyPropertyChanged(BR.password)
+            adapter.fetchClients()
         }
-        fun onClientsChanged() = adapter.fetchClients()
     }
 
     class ClientViewHolder(val binding: ClientBinding) : RecyclerView.ViewHolder(binding.root)
     inner class ClientAdapter : RecyclerView.Adapter<ClientViewHolder>() {
         private var owner: WifiP2pDevice? = null
         private lateinit var clients: MutableCollection<WifiP2pDevice>
+        private lateinit var arpCache: ArpCache
 
         fun fetchClients() {
             val binder = binder!!
             if (data.running) {
                 owner = binder.service.group.owner
-                clients = binder.service.clients
+                clients = binder.service.group.clientList
+                arpCache = ArpCache(binder.service.downstream!!)
             } else owner = null
             notifyDataSetChanged()  // recreate everything
         }
@@ -80,10 +80,15 @@ class MainActivity : AppCompatActivity(), ServiceConnection {
                 ClientViewHolder(ClientBinding.inflate(LayoutInflater.from(parent.context)))
 
         override fun onBindViewHolder(holder: ClientViewHolder, position: Int) {
-            holder.binding.device = when (position) {
+            val device = when (position) {
                 0 -> owner
                 else -> clients.elementAt(position - 1)
             }
+            holder.binding.device = device
+            holder.binding.ipAddress = when (position) {
+                0 -> binder?.service?.hostAddress?.hostAddress?.toString()
+                else -> arpCache[device?.deviceAddress]
+            }
             holder.binding.executePendingBindings()
         }
 

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

@@ -3,44 +3,31 @@
     xmlns:tools="http://schemas.android.com/tools"
     xmlns:android="http://schemas.android.com/apk/res/android">
     <data>
+        <import type="android.view.View"/>
         <variable
             name="device"
             type="android.net.wifi.p2p.WifiP2pDevice"/>
+        <variable
+            name="ipAddress"
+            type="String"/>
     </data>
     <LinearLayout
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:orientation="vertical">
 
-        <TextView
-            android:layout_width="match_parent"
-            android:layout_height="wrap_content"
-            android:text="@{device.deviceName}"
-            android:textAppearance="@style/TextAppearance.AppCompat.Subhead"
-            tools:text="Device name"/>
-
         <TextView
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
             android:text="@{device.deviceAddress}"
+            android:textAppearance="@style/TextAppearance.AppCompat.Subhead"
             tools:text="xx:xx:xx:xx:xx:xx"/>
 
         <TextView
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
-            android:text="@{device.primaryDeviceType}"
+            android:visibility="@{ipAddress == null ? View.GONE : View.VISIBLE}"
-            tools:text="Primary type"/>
+            android:text="@{ipAddress}"
-
+            tools:text="192.168.49.123"/>
-        <TextView
-            android:layout_width="match_parent"
-            android:layout_height="wrap_content"
-            android:text="@{device.secondaryDeviceType}"
-            tools:text="Secondary type"/>
-
-        <TextView
-            android:layout_width="match_parent"
-            android:layout_height="wrap_content"
-            android:text="@{Integer.toString(device.status)}"
-            tools:text="Status"/>
     </LinearLayout>
 </layout>