src/libcharon/plugins/kernel_libipsec/kernel_libipsec_plugin.c

   1 /*
   2  * Copyright (C) 2012-2013 Tobias Brunner
   3  * Hochschule fuer Technik Rapperswil
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License as published by the
   7  * Free Software Foundation; either version 2 of the License, or (at your
   8  * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  12  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  13  * for more details.
  14  */
  15
  16 #include "kernel_libipsec_plugin.h"
  17 #include "kernel_libipsec_ipsec.h"
  18 #include "kernel_libipsec_router.h"
  19
  20 #include <daemon.h>
  21 #include <ipsec.h>
  22 #include <networking/tun_device.h>
  23
  24 #define TUN_DEFAULT_MTU 1400
  25
  26 typedef struct private_kernel_libipsec_plugin_t private_kernel_libipsec_plugin_t;
  27
  28 /**
  29  * private data of "kernel" libipsec plugin
  30  */
  31 struct private_kernel_libipsec_plugin_t {
  32
  33         /**
  34          * implements plugin interface
  35          */
  36         kernel_libipsec_plugin_t public;
  37
  38         /**
  39          * TUN device created by this plugin
  40          */
  41         tun_device_t *tun;
  42
  43         /**
  44          * Packet router
  45          */
  46         kernel_libipsec_router_t *router;
  47 };
  48
  49 METHOD(plugin_t, get_name, char*,
  50         private_kernel_libipsec_plugin_t *this)
  51 {
  52         return "kernel-libipsec";
  53 }
  54
  55 /**
  56  * Create the kernel_libipsec_router_t instance
  57  */
  58 static bool create_router(private_kernel_libipsec_plugin_t *this,
  59                                                   plugin_feature_t *feature, bool reg, void *arg)
  60 {
  61         if (reg)
  62         {       /* registers as packet handler etc. */
  63                 this->router = kernel_libipsec_router_create();
  64         }
  65         else
  66         {
  67                 DESTROY_IF(this->router);
  68         }
  69         return TRUE;
  70 }
  71
  72 METHOD(plugin_t, get_features, int,
  73         private_kernel_libipsec_plugin_t *this, plugin_feature_t *features[])
  74 {
  75         static plugin_feature_t f[] = {
  76                 PLUGIN_CALLBACK(kernel_ipsec_register, kernel_libipsec_ipsec_create),
  77                         PLUGIN_PROVIDE(CUSTOM, "kernel-ipsec"),
  78                 PLUGIN_CALLBACK((plugin_feature_callback_t)create_router, NULL),
  79                         PLUGIN_PROVIDE(CUSTOM, "kernel-libipsec-router"),
  80                                 PLUGIN_DEPENDS(CUSTOM, "libcharon-receiver"),
  81         };
  82         *features = f;
  83         return countof(f);
  84 }
  85
  86 METHOD(plugin_t, destroy, void,
  87         private_kernel_libipsec_plugin_t *this)
  88 {
  89         if (this->tun)
  90         {
  91                 lib->set(lib, "kernel-libipsec-tun", NULL);
  92                 this->tun->destroy(this->tun);
  93         }
  94         libipsec_deinit();
  95         free(this);
  96 }
  97
  98 /*
  99  * see header file
 100  */
 101 plugin_t *kernel_libipsec_plugin_create()
 102 {
 103         private_kernel_libipsec_plugin_t *this;
 104
 105         if (!lib->caps->check(lib->caps, CAP_NET_ADMIN))
 106         {       /* required to create TUN devices */
 107                 DBG1(DBG_KNL, "kernel-libipsec plugin requires CAP_NET_ADMIN "
 108                          "capability");
 109                 return NULL;
 110         }
 111
 112         INIT(this,
 113                 .public = {
 114                         .plugin = {
 115                                 .get_name = _get_name,
 116                                 .get_features = _get_features,
 117                                 .destroy = _destroy,
 118                         },
 119                 },
 120         );
 121
 122         if (!libipsec_init())
 123         {
 124                 DBG1(DBG_LIB, "initialization of libipsec failed");
 125                 destroy(this);
 126                 return NULL;
 127         }
 128
 129         this->tun = tun_device_create("ipsec%d");
 130         if (!this->tun)
 131         {
 132                 DBG1(DBG_KNL, "failed to create TUN device");
 133                 destroy(this);
 134                 return NULL;
 135         }
 136         if (!this->tun->set_mtu(this->tun, TUN_DEFAULT_MTU) ||
 137                 !this->tun->up(this->tun))
 138         {
 139                 DBG1(DBG_KNL, "failed to configure TUN device");
 140                 destroy(this);
 141                 return NULL;
 142         }
 143         lib->set(lib, "kernel-libipsec-tun", this->tun);
 144
 145         /* set TUN device as default to install VIPs */
 146         lib->settings->set_str(lib->settings, "%s.install_virtual_ip_on",
 147                                                    this->tun->get_name(this->tun), charon->name);
 148         return &this->public.plugin;
 149 }