Added android.net.VpnService wrapper around charon (loaded via JNI).

src/frontends/android/AndroidManifest.xml

@@ -5,6 +5,7 @@
     android:versionName="1.0" >
 
     <uses-sdk android:minSdkVersion="15" />
+    <uses-permission android:name="android.permission.INTERNET" />
 
     <application
         android:icon="@drawable/ic_launcher"
@@ -18,6 +19,11 @@
                 <category android:name="android.intent.category.LAUNCHER" />
             </intent-filter>
         </activity>
+        <service android:name=".CharonVpnService" android:permission="android.permission.BIND_VPN_SERVICE">
+            <intent-filter>
+                <action android:name="android.net.VpnService"/>
+            </intent-filter>
+        </service>
     </application>
 
 </manifest>

src/frontends/android/jni/Android.mk

@@ -56,6 +56,7 @@ strongswan_CFLAGS += \
 include $(addprefix $(LOCAL_PATH)/,$(addsuffix /Android.mk, \
 		vstr \
 		openssl \
+		libandroidbridge \
 		strongswan/src/libcharon \
 		strongswan/src/libhydra \
 		strongswan/src/libstrongswan \

src/frontends/android/jni/libandroidbridge/Android.mk

@@ -0,0 +1,33 @@
+LOCAL_PATH := $(call my-dir)
+include $(CLEAR_VARS)
+
+# copy-n-paste from Makefile.am
+LOCAL_SRC_FILES := \
+charonservice.c
+
+# build libandroidbridge -------------------------------------------------------
+
+LOCAL_C_INCLUDES += \
+	$(libvstr_PATH) \
+	$(strongswan_PATH)/src/libhydra \
+	$(strongswan_PATH)/src/libcharon \
+	$(strongswan_PATH)/src/libstrongswan
+
+LOCAL_CFLAGS := $(strongswan_CFLAGS) \
+	-DPLUGINS='"$(strongswan_CHARON_PLUGINS)"'
+
+LOCAL_MODULE := libandroidbridge
+
+LOCAL_MODULE_TAGS := optional
+
+LOCAL_ARM_MODE := arm
+
+LOCAL_PRELINK_MODULE := false
+
+LOCAL_LDLIBS := -llog
+
+LOCAL_SHARED_LIBRARIES := libstrongswan libhydra libcharon
+
+include $(BUILD_SHARED_LIBRARY)
+
+

src/frontends/android/jni/libandroidbridge/charonservice.c

@@ -0,0 +1,113 @@
+/*
+ * Copyright (C) 2012 Tobias Brunner
+ * Hochschule fuer Technik Rapperswil
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * for more details.
+ */
+
+#include <string.h>
+#include <android/log.h>
+#include <jni.h>
+
+#include <hydra.h>
+#include <daemon.h>
+#include <library.h>
+
+#define JNI_PACKAGE org_strongswan_android
+
+#define JNI_METHOD_PP(pack, klass, name, ret, ...) \
+	ret Java_##pack##_##klass##_##name(JNIEnv *env, jobject this, ##__VA_ARGS__)
+
+#define JNI_METHOD_P(pack, klass, name, ret, ...) \
+	JNI_METHOD_PP(pack, klass, name, ret, ##__VA_ARGS__)
+
+#define JNI_METHOD(klass, name, ret, ...) \
+	JNI_METHOD_P(JNI_PACKAGE, klass, name, ret, ##__VA_ARGS__)
+
+/**
+ * hook in library for debugging messages
+ */
+extern void (*dbg) (debug_t group, level_t level, char *fmt, ...);
+
+/**
+ * Logging hook for library logs, using android specific logging
+ */
+static void dbg_android(debug_t group, level_t level, char *fmt, ...)
+{
+	va_list args;
+
+	if (level <= 4)
+	{
+		char sgroup[16], buffer[8192];
+		char *current = buffer, *next;
+		snprintf(sgroup, sizeof(sgroup), "%N", debug_names, group);
+		va_start(args, fmt);
+		vsnprintf(buffer, sizeof(buffer), fmt, args);
+		va_end(args);
+		while (current)
+		{	/* log each line separately */
+			next = strchr(current, '\n');
+			if (next)
+			{
+				*(next++) = '\0';
+			}
+			__android_log_print(ANDROID_LOG_INFO, "charon", "00[%s] %s\n",
+								sgroup, current);
+			current = next;
+		}
+	}
+}
+
+/**
+ * Initialize charon and the libraries via JNI
+ */
+JNI_METHOD(CharonVpnService, initializeCharon, void)
+{
+	/* logging for library during initialization, as we have no bus yet */
+	dbg = dbg_android;
+
+	/* initialize library */
+	if (!library_init(NULL))
+	{
+		library_deinit();
+		return;
+	}
+
+	if (!libhydra_init("charon"))
+	{
+		libhydra_deinit();
+		library_deinit();
+		return;
+	}
+
+	if (!libcharon_init("charon") ||
+		!charon->initialize(charon, PLUGINS))
+	{
+		libcharon_deinit();
+		libhydra_deinit();
+		library_deinit();
+		return;
+	}
+
+	/* start daemon (i.e. the threads in the thread-pool) */
+	charon->start(charon);
+}
+
+/**
+ * Initialize charon and the libraries via JNI
+ */
+JNI_METHOD(CharonVpnService, deinitializeCharon, void)
+{
+	libcharon_deinit();
+	libhydra_deinit();
+	library_deinit();
+}
+

src/frontends/android/src/org/strongswan/android/CharonVpnService.java

@@ -0,0 +1,50 @@
+package org.strongswan.android;
+
+import android.content.Intent;
+import android.net.VpnService;
+
+public class CharonVpnService extends VpnService {
+
+	@Override
+	public int onStartCommand(Intent intent, int flags, int startId) {
+		// called whenever the service is started with startService
+		// create our own thread because we are running in the calling processes main thread
+		return super.onStartCommand(intent, flags, startId);
+	}
+
+	@Override
+	public void onCreate() {
+		// onCreate is only called once
+		initializeCharon();
+		super.onCreate();
+	}
+
+	@Override
+	public void onDestroy() {
+		// called once the service is to be destroyed
+		deinitializeCharon();
+		super.onDestroy();
+	}
+
+	/**
+	 * Initialization of charon, provided by libandroidbridge.so
+	 */
+	public native void initializeCharon();
+
+	/**
+	 * Deinitialize charon, provided by libandroidbridge.so
+	 */
+	public native void deinitializeCharon();
+
+	/*
+	 * The libraries are extracted to /data/data/org.strongswan.android/...
+	 * during installation.
+	 */
+	static {
+		System.loadLibrary("crypto");
+		System.loadLibrary("strongswan");
+		System.loadLibrary("hydra");
+		System.loadLibrary("charon");
+		System.loadLibrary("androidbridge");
+	}
+}

src/frontends/android/src/org/strongswan/android/strongSwanActivity.java

@@ -1,13 +1,32 @@
 package org.strongswan.android;
 
 import android.app.Activity;
+import android.content.Intent;
+import android.net.VpnService;
 import android.os.Bundle;
 
 public class strongSwanActivity extends Activity {
-    /** Called when the activity is first created. */
-    @Override
-    public void onCreate(Bundle savedInstanceState) {
-        super.onCreate(savedInstanceState);
-        setContentView(R.layout.main);
-    }
+	@Override
+	public void onCreate(Bundle savedInstanceState) {
+		super.onCreate(savedInstanceState);
+		setContentView(R.layout.main);
+		startVpnService();
+	}
+
+	private void startVpnService() {
+		Intent intent = VpnService.prepare(this);
+		if (intent != null) {
+			startActivityForResult(intent, 0);
+		} else {
+			onActivityResult(0, RESULT_OK, null);
+		}
+	}
+
+	@Override
+	protected void onActivityResult(int requestCode, int resultCode, Intent data) {
+		if (resultCode == RESULT_OK) {
+			Intent intent = new Intent(this, CharonVpnService.class);
+			startService(intent);
+		}
+	}
 }