android: Added NetworkManager class which allows to retrieve a local IP address

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

@@ -11,6 +11,7 @@ backend/android_service.c backend/android_service.h \
 charonservice.c charonservice.h \
 kernel/android_ipsec.c kernel/android_ipsec.h \
 kernel/android_net.c kernel/android_net.h \
+kernel/network_manager.c kernel/network_manager.h \
 vpnservice_builder.c vpnservice_builder.h
 
 # build libandroidbridge -------------------------------------------------------

src/frontends/android/jni/libandroidbridge/kernel/network_manager.c

@@ -0,0 +1,137 @@
+/*
+ * 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 "network_manager.h"
+
+#include "../android_jni.h"
+#include <debug.h>
+
+typedef struct private_network_manager_t private_network_manager_t;
+
+struct private_network_manager_t {
+
+	/**
+	 * Public interface
+	 */
+	network_manager_t public;
+
+	/**
+	 * Reference to NetworkManager object
+	 */
+	jobject obj;
+
+	/**
+	 * Java class for NetworkManager
+	 */
+	jclass cls;
+};
+
+METHOD(network_manager_t, get_local_address, host_t*,
+	private_network_manager_t *this, bool ipv4)
+{
+	JNIEnv *env;
+	jmethodID method_id;
+	jstring jaddr;
+	char *addr;
+	host_t *host;
+
+	androidjni_attach_thread(&env);
+	method_id = (*env)->GetMethodID(env, this->cls, "getLocalAddress",
+									"(Z)Ljava/lang/String;");
+	if (!method_id)
+	{
+		goto failed;
+	}
+	jaddr = (*env)->CallObjectMethod(env, this->obj, method_id, ipv4);
+	if (!jaddr)
+	{
+		goto failed;
+	}
+	addr = androidjni_convert_jstring(env, jaddr);
+	androidjni_detach_thread();
+	host = host_create_from_string(addr, 0);
+	free(addr);
+	return host;
+
+failed:
+	androidjni_exception_occurred(env);
+	androidjni_detach_thread();
+	return NULL;
+}
+
+METHOD(network_manager_t, destroy, void,
+	private_network_manager_t *this)
+{
+	JNIEnv *env;
+
+	androidjni_attach_thread(&env);
+	if (this->obj)
+	{
+		(*env)->DeleteGlobalRef(env, this->obj);
+	}
+	if (this->cls)
+	{
+		(*env)->DeleteGlobalRef(env, this->cls);
+	}
+	androidjni_detach_thread();
+	free(this);
+}
+
+/*
+ * Described in header.
+ */
+network_manager_t *network_manager_create()
+{
+	private_network_manager_t *this;
+	JNIEnv *env;
+	jmethodID method_id;
+	jobject obj;
+	jclass cls;
+
+	INIT(this,
+		.public = {
+			.get_local_address = _get_local_address,
+			.destroy = _destroy,
+		},
+	);
+
+	androidjni_attach_thread(&env);
+	cls = (*env)->FindClass(env, JNI_PACKAGE_STRING "/NetworkManager");
+	if (!cls)
+	{
+		goto failed;
+	}
+	this->cls = (*env)->NewGlobalRef(env, cls);
+	method_id = (*env)->GetMethodID(env, cls, "<init>",
+									"()V");
+	if (!method_id)
+	{
+		goto failed;
+	}
+	obj = (*env)->NewObject(env, cls, method_id);
+	if (!obj)
+	{
+		goto failed;
+	}
+	this->obj = (*env)->NewGlobalRef(env, obj);
+	androidjni_detach_thread();
+	return &this->public;
+
+failed:
+	DBG1(DBG_KNL, "failed to build NetworkManager object");
+	androidjni_exception_occurred(env);
+	androidjni_detach_thread();
+	destroy(this);
+	return NULL;
+};

src/frontends/android/jni/libandroidbridge/kernel/network_manager.h

@@ -0,0 +1,59 @@
+/*
+ * 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.
+ */
+
+/**
+ * @defgroup network_manager network_manager
+ * @{ @ingroup kernel_android
+ */
+
+#ifndef NETWORK_MANAGER_H_
+#define NETWORK_MANAGER_H_
+
+#include <jni.h>
+
+#include <library.h>
+#include <utils/host.h>
+
+typedef struct network_manager_t network_manager_t;
+
+/**
+ * NetworkManager, used to retrieve local IP addresses.
+ *
+ * Communicates with NetworkManager via JNI
+ */
+struct network_manager_t {
+
+	/**
+	 * Get a local address
+	 *
+	 * @param ipv4				TRUE to get an IPv4 address
+	 * @return					the address or NULL if none available
+	 */
+	host_t *(*get_local_address)(network_manager_t *this, bool ipv4);
+
+	/**
+	 * Destroy a network_manager_t instance
+	 */
+	void (*destroy)(network_manager_t *this);
+};
+
+/**
+ * Create a network_manager_t instance
+ *
+ * @return						network_manager_t instance
+ */
+network_manager_t *network_manager_create();
+
+#endif /** NETWORK_MANAGER_H_ @}*/

src/frontends/android/src/org/strongswan/android/logic/NetworkManager.java

@@ -0,0 +1,77 @@
+/*
+ * 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.
+ */
+
+package org.strongswan.android.logic;
+
+import java.net.Inet4Address;
+import java.net.Inet6Address;
+import java.net.InetAddress;
+import java.net.NetworkInterface;
+import java.net.SocketException;
+import java.util.Enumeration;
+
+public class NetworkManager
+{
+	public NetworkManager()
+	{
+	}
+
+	/**
+	 * Function that retrieves a local address of the given family.
+	 *
+	 * @param ipv4 true to return an IPv4 address, false for IPv6
+	 * @return string representation of an IPv4 address, or null if none found
+	 */
+	public String getLocalAddress(boolean ipv4)
+	{
+		try
+		{
+			Enumeration<NetworkInterface> en = NetworkInterface.getNetworkInterfaces();
+			if (en == null)
+			{	/* no interfaces at all */
+				return null;
+			}
+			while (en.hasMoreElements())
+			{
+				NetworkInterface intf = en.nextElement();
+				if (intf.isLoopback() || !intf.isUp() ||
+					intf.getName().startsWith("tun"))
+				{
+					continue;
+				}
+				Enumeration<InetAddress> enumIpAddr = intf.getInetAddresses();
+				while (enumIpAddr.hasMoreElements())
+				{
+					InetAddress inetAddress = enumIpAddr.nextElement();
+					if (inetAddress.isLoopbackAddress())
+					{
+						continue;
+					}
+					if ((ipv4 && inetAddress instanceof Inet4Address) ||
+						(!ipv4 && inetAddress instanceof Inet6Address))
+					{
+						return inetAddress.getHostAddress();
+					}
+				}
+			}
+		}
+		catch (SocketException ex)
+		{
+			ex.printStackTrace();
+			return null;
+		}
+		return null;
+	}
+}