Temporary Wi-Fi hotspot for bypassing tethering limits (#18)

* First draft of temporary hotspot * Refactor with LocalOnlyInterfaceManager * Refactor LocalOnlyHotspotService * Localize * Update strict summary
2018-05-02 17:53:06 -07:00
parent 0a47cfdf1c
commit 2fe7703d6d
15 changed files with 420 additions and 185 deletions
--- a/mobile/src/main/java/be/mygod/vpnhotspot/LocalOnlyInterfaceManager.kt
+++ b/mobile/src/main/java/be/mygod/vpnhotspot/LocalOnlyInterfaceManager.kt
@@ -0,0 +1,65 @@
+package be.mygod.vpnhotspot
+
+import android.content.BroadcastReceiver
+import android.content.Context
+import android.content.Intent
+import android.support.v4.content.LocalBroadcastManager
+import android.widget.Toast
+import be.mygod.vpnhotspot.App.Companion.app
+import be.mygod.vpnhotspot.net.Routing
+import be.mygod.vpnhotspot.net.VpnMonitor
+import java.net.InetAddress
+import java.net.SocketException
+
+class LocalOnlyInterfaceManager(val downstream: String, private val owner: InetAddress? = null) :
+        BroadcastReceiver(), VpnMonitor.Callback {
+    private var routing: Routing? = null
+    private var dns = emptyList<InetAddress>()
+
+    init {
+        LocalBroadcastManager.getInstance(app).registerReceiver(this, intentFilter(App.ACTION_CLEAN_ROUTINGS))
+        VpnMonitor.registerCallback(this) { initRouting() }
+    }
+
+    override fun onAvailable(ifname: String, dns: List<InetAddress>) {
+        val routing = routing
+        initRouting(ifname, if (routing == null) owner else {
+            routing.stop()
+            check(routing.upstream == null)
+            routing.hostAddress
+        }, dns)
+    }
+    override fun onLost(ifname: String) {
+        val routing = routing ?: return
+        if (!routing.stop()) app.toast(R.string.noisy_su_failure)
+        initRouting(null, routing.hostAddress, emptyList())
+    }
+    override fun onReceive(context: Context?, intent: Intent?) {
+        val routing = routing ?: return
+        routing.started = false
+        initRouting(routing.upstream, routing.hostAddress, dns)
+    }
+
+    private fun initRouting(upstream: String? = null, owner: InetAddress? = this.owner,
+                            dns: List<InetAddress> = this.dns) {
+        try {
+            val routing = Routing(upstream, downstream, owner)
+            this.routing = routing
+            this.dns = dns
+            val strict = app.pref.getBoolean("service.repeater.strict", false)
+            if (strict && upstream == null) return  // in this case, nothing to be done
+            if (routing.ipForward()                 // local only interfaces may not enable ip_forward
+                            .rule().forward(strict).masquerade(strict).dnsRedirect(dns).start()) return
+            app.toast(R.string.noisy_su_failure)
+        } catch (e: SocketException) {
+            Toast.makeText(app, e.message, Toast.LENGTH_SHORT).show()
+            routing = null
+        }
+    }
+
+    fun stop() {
+        VpnMonitor.unregisterCallback(this)
+        LocalBroadcastManager.getInstance(app).unregisterReceiver(this)
+        if (routing?.stop() == false) app.toast(R.string.noisy_su_failure)
+    }
+}