Initial commit

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

@@ -0,0 +1,181 @@
+package eu.neilalexander.yggdrasil
+
+import android.content.Intent
+import android.net.Uri
+import android.net.VpnService
+import android.os.Handler
+import android.os.Message
+import android.os.ParcelFileDescriptor
+import android.util.Log
+import androidx.localbroadcastmanager.content.LocalBroadcastManager
+import mobile.Yggdrasil
+import org.json.JSONArray
+import java.io.FileInputStream
+import java.io.FileOutputStream
+import java.util.concurrent.atomic.AtomicBoolean
+import kotlin.concurrent.thread
+
+
+class PacketTunnelProvider: VpnService() {
+    companion object {
+        const val RECEIVER_INTENT = "eu.neilalexander.yggdrasil.PacketTunnelProvider.MESSAGE"
+
+        const val ACTION_START = "eu.neilalexander.yggdrasil.PacketTunnelProvider.START"
+        const val ACTION_STOP = "eu.neilalexander.yggdrasil.PacketTunnelProvider.STOP"
+    }
+
+    private var yggdrasil = Yggdrasil()
+    private var started = AtomicBoolean()
+
+    private lateinit var config: ConfigurationProxy
+    private lateinit var parcel: ParcelFileDescriptor
+
+    private lateinit var readerThread: Thread
+    private lateinit var writerThread: Thread
+    private lateinit var updateThread: Thread
+
+    private lateinit var readerStream: FileInputStream
+    private lateinit var writerStream: FileOutputStream
+
+    override fun onCreate() {
+        super.onCreate()
+        config = ConfigurationProxy(applicationContext)
+    }
+
+    override fun onDestroy() {
+        super.onDestroy()
+        stop()
+    }
+
+    override fun onStartCommand(intent: Intent?, flags: Int, startId: Int): Int {
+        if (intent == null) {
+            return START_NOT_STICKY
+        }
+        return when (intent.action ?: ACTION_STOP) {
+            ACTION_START -> {
+                start(); START_STICKY
+            }
+            ACTION_STOP -> {
+                stop(); START_NOT_STICKY
+            }
+            else -> {
+                stop(); START_NOT_STICKY
+            }
+        }
+    }
+
+    private fun start() {
+        if (!started.compareAndSet(false, true)) {
+            return
+        }
+
+        Log.d("PacketTunnelProvider", config.getJSON().toString())
+        yggdrasil.startJSON(config.getJSONByteArray())
+
+        val address = yggdrasil.addressString
+        var builder = Builder()
+            .addAddress(address, 7)
+            .addRoute("200::", 7)
+            .setBlocking(true)
+            .setMtu(yggdrasil.mtu.toInt())
+            .setSession("Yggdrasil")
+
+        parcel = builder.establish()
+        if (parcel == null || !parcel.fileDescriptor.valid()) {
+            stop()
+            return
+        }
+
+        readerStream = FileInputStream(parcel.fileDescriptor)
+        writerStream = FileOutputStream(parcel.fileDescriptor)
+
+        readerThread = thread {
+            reader()
+        }
+        writerThread = thread {
+            writer()
+        }
+        updateThread = thread {
+            updater()
+        }
+
+        val intent = Intent(RECEIVER_INTENT)
+        intent.putExtra("type", "state")
+        intent.putExtra("started", true)
+        intent.putExtra("ip", yggdrasil.addressString)
+        intent.putExtra("subnet", yggdrasil.subnetString)
+        intent.putExtra("coords", yggdrasil.coordsString)
+        intent.putExtra("peers", JSONArray(yggdrasil.peersJSON).length())
+        LocalBroadcastManager.getInstance(this).sendBroadcast(intent)
+    }
+
+    private fun stop() {
+        if (!started.compareAndSet(true, false)) {
+            return
+        }
+        if (readerThread != null) {
+            readerStream.close()
+            readerThread.interrupt()
+        }
+        if (writerThread != null) {
+            writerStream.close()
+            writerThread.interrupt()
+        }
+        if (updateThread != null) {
+            updateThread.interrupt()
+        }
+        parcel.close()
+        yggdrasil.stop()
+        stopSelf()
+
+        val intent = Intent(RECEIVER_INTENT)
+        intent.putExtra("type", "state")
+        intent.putExtra("started", false)
+        LocalBroadcastManager.getInstance(this).sendBroadcast(intent)
+    }
+
+    private fun updater() {
+        updates@ while (!updateThread.isInterrupted) {
+            val intent = Intent(RECEIVER_INTENT)
+            intent.putExtra("type", "state")
+            intent.putExtra("started", true)
+            intent.putExtra("ip", yggdrasil.addressString)
+            intent.putExtra("subnet", yggdrasil.subnetString)
+            intent.putExtra("coords", yggdrasil.coordsString)
+            intent.putExtra("peers", yggdrasil.peersJSON)
+            intent.putExtra("dht", yggdrasil.dhtjson)
+            LocalBroadcastManager.getInstance(this).sendBroadcast(intent)
+
+            try {
+                Thread.sleep(2000)
+            } catch (e: java.lang.InterruptedException) {
+                return
+            }
+        }
+    }
+
+    private fun writer() {
+        writes@ while (!writerThread.isInterrupted && writerStream.fd.valid()) {
+            try {
+                val b = yggdrasil.recv()
+                writerStream.write(b)
+            } catch (e: Exception) {
+                break@writes
+            }
+        }
+        stop()
+    }
+
+    private fun reader() {
+        var b = ByteArray(65535)
+        reads@ while (!readerThread.isInterrupted && readerStream.fd.valid()) {
+            try {
+                val n = readerStream.read(b)
+                yggdrasil.send(b.sliceArray(0..n))
+            } catch (e: Exception) {
+                break@reads
+            }
+        }
+        stop()
+    }
+}