Added a farp plugin stop to spoof ARP requests

configure.in

@@ -117,6 +117,7 @@ ARG_ENABL_SET([kernel-klips],   [enable the KLIPS kernel interface.])
 ARG_DISBL_SET([socket-default], [disable default socket implementation for charon.])
 ARG_ENABL_SET([socket-raw],     [enable raw socket implementation of charon, enforced if pluto is enabled])
 ARG_ENABL_SET([socket-dynamic], [enable dynamic socket implementation for charon])
+ARG_ENABL_SET([farp],           [enable ARP faking plugin that responds to ARP requests to peers virtual IP])
 ARG_ENABL_SET([nat-transport],  [enable NAT traversal with IPsec transport mode in pluto.])
 ARG_DISBL_SET([vendor-id],      [disable the sending of the strongSwan vendor ID in pluto.])
 ARG_DISBL_SET([xauth-vid],      [disable the sending of the XAUTH vendor ID.])
@@ -822,6 +823,7 @@ AM_CONDITIONAL(USE_KERNEL_KLIPS, test x$kernel_klips = xtrue)
 AM_CONDITIONAL(USE_SOCKET_DEFAULT, test x$socket_default = xtrue)
 AM_CONDITIONAL(USE_SOCKET_RAW, test x$socket_raw = xtrue)
 AM_CONDITIONAL(USE_SOCKET_DYNAMIC, test x$socket_dynamic = xtrue)
+AM_CONDITIONAL(USE_FARP, test x$farp = xtrue)
 
 dnl other options
 dnl =============
@@ -927,6 +929,7 @@ AC_OUTPUT(
 	src/libcharon/plugins/socket_default/Makefile
 	src/libcharon/plugins/socket_raw/Makefile
 	src/libcharon/plugins/socket_dynamic/Makefile
+	src/libcharon/plugins/farp/Makefile
 	src/libcharon/plugins/smp/Makefile
 	src/libcharon/plugins/sql/Makefile
 	src/libcharon/plugins/medsrv/Makefile

src/libcharon/Makefile.am

@@ -205,6 +205,14 @@ if MONOLITHIC
 endif
 endif
 
+if USE_FARP
+  SUBDIRS += plugins/farp
+  PLUGINS += farp
+if MONOLITHIC
+  libcharon_la_LIBADD += plugins/farp/libstrongswan-farp.la
+endif
+endif
+
 if USE_STROKE
   SUBDIRS += plugins/stroke
   PLUGINS += stroke

src/libcharon/plugins/farp/Makefile.am

@@ -0,0 +1,14 @@
+
+INCLUDES = -I$(top_srcdir)/src/libstrongswan -I$(top_srcdir)/src/libcharon
+
+AM_CFLAGS = -rdynamic
+
+if MONOLITHIC
+noinst_LTLIBRARIES = libstrongswan-farp.la
+else
+plugin_LTLIBRARIES = libstrongswan-farp.la
+endif
+
+libstrongswan_farp_la_SOURCES = farp_plugin.h farp_plugin.c
+
+libstrongswan_farp_la_LDFLAGS = -module -avoid-version

src/libcharon/plugins/farp/farp_plugin.c

@@ -0,0 +1,52 @@
+/*
+ * Copyright (C) 2010 Martin Willi
+ * Copyright (C) 2010 revosec AG
+ *
+ * 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 "farp_plugin.h"
+
+#include <daemon.h>
+
+typedef struct private_farp_plugin_t private_farp_plugin_t;
+
+/**
+ * private data of farp plugin
+ */
+struct private_farp_plugin_t {
+
+	/**
+	 * implements plugin interface
+	 */
+	farp_plugin_t public;
+};
+
+METHOD(plugin_t, destroy, void,
+	private_farp_plugin_t *this)
+{
+	free(this);
+}
+
+/**
+ * Plugin constructor
+ */
+plugin_t *farp_plugin_create()
+{
+	private_farp_plugin_t *this;
+
+	INIT(this,
+		.public.plugin.destroy = _destroy,
+	);
+
+	return &this->public.plugin;
+}
+

src/libcharon/plugins/farp/farp_plugin.h

@@ -0,0 +1,42 @@
+/*
+ * Copyright (C) 2010 Martin Willi
+ * Copyright (C) 2010 revosec AG
+ *
+ * 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 farp farp
+ * @ingroup cplugins
+ *
+ * @defgroup farp_plugin farp_plugin
+ * @{ @ingroup farp
+ */
+
+#ifndef FARP_PLUGIN_H_
+#define FARP_PLUGIN_H_
+
+#include <plugins/plugin.h>
+
+typedef struct farp_plugin_t farp_plugin_t;
+
+/**
+ * ARP faking plugin that responds to ARP requests to peers virtual IP.
+ */
+struct farp_plugin_t {
+
+	/**
+	 * implements plugin interface
+	 */
+	plugin_t plugin;
+};
+
+#endif /** FARP_PLUGIN_H_ @}*/