src/charon/sa/tasks/ike_rekey.c

   1 /**
   2  * @file ike_rekey.c
   3  *
   4  * @brief Implementation of the ike_rekey task.
   5  *
   6  */
   7
   8 /*
   9  * Copyright (C) 2005-2007 Martin Willi
  10  * Copyright (C) 2005 Jan Hutter
  11  * Hochschule fuer Technik Rapperswil
  12  *
  13  * This program is free software; you can redistribute it and/or modify it
  14  * under the terms of the GNU General Public License as published by the
  15  * Free Software Foundation; either version 2 of the License, or (at your
  16  * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
  17  *
  18  * This program is distributed in the hope that it will be useful, but
  19  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  20  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  21  * for more details.
  22  */
  23
  24 #include "ike_rekey.h"
  25
  26 #include <daemon.h>
  27 #include <encoding/payloads/notify_payload.h>
  28 #include <sa/tasks/ike_init.h>
  29 #include <queues/jobs/delete_ike_sa_job.h>
  30 #include <queues/jobs/rekey_ike_sa_job.h>
  31
  32
  33 typedef struct private_ike_rekey_t private_ike_rekey_t;
  34
  35 /**
  36  * Private members of a ike_rekey_t task.
  37  */
  38 struct private_ike_rekey_t {
  39
  40         /**
  41          * Public methods and task_t interface.
  42          */
  43         ike_rekey_t public;
  44
  45         /**
  46          * Assigned IKE_SA.
  47          */
  48         ike_sa_t *ike_sa;
  49
  50         /**
  51          * New IKE_SA which replaces the current one
  52          */
  53         ike_sa_t *new_sa;
  54
  55         /**
  56          * Are we the initiator?
  57          */
  58         bool initiator;
  59
  60         /**
  61          * the IKE_INIT task which is reused to simplify rekeying
  62          */
  63         ike_init_t *ike_init;
  64
  65         /**
  66          * colliding task detected by the task manager
  67          */
  68         task_t *collision;
  69 };
  70
  71 /**
  72  * Implementation of task_t.build for initiator
  73  */
  74 static status_t build_i(private_ike_rekey_t *this, message_t *message)
  75 {
  76         connection_t *connection;
  77         policy_t *policy;
  78         ike_sa_id_t *id;
  79
  80         id = ike_sa_id_create(0, 0, TRUE);
  81         this->new_sa = charon->ike_sa_manager->checkout(charon->ike_sa_manager, id);
  82         id->destroy(id);
  83
  84         connection = this->ike_sa->get_connection(this->ike_sa);
  85         policy = this->ike_sa->get_policy(this->ike_sa);
  86         this->new_sa->set_connection(this->new_sa, connection);
  87         this->new_sa->set_policy(this->new_sa, policy);
  88
  89         this->ike_init = ike_init_create(this->new_sa, TRUE, this->ike_sa);
  90         this->ike_init->task.build(&this->ike_init->task, message);
  91
  92         this->ike_sa->set_state(this->ike_sa, IKE_REKEYING);
  93
  94         return NEED_MORE;
  95 }
  96
  97 /**
  98  * Implementation of task_t.process for initiator
  99  */
 100 static status_t process_r(private_ike_rekey_t *this, message_t *message)
 101 {
 102         connection_t *connection;
 103         policy_t *policy;
 104         ike_sa_id_t *id;
 105         iterator_t *iterator;
 106         child_sa_t *child_sa;
 107
 108         if (this->ike_sa->get_state(this->ike_sa) == IKE_DELETING)
 109         {
 110                 DBG1(DBG_IKE, "peer initiated rekeying, but we are deleting");
 111                 return NEED_MORE;
 112         }
 113
 114         iterator = this->ike_sa->create_child_sa_iterator(this->ike_sa);
 115         while (iterator->iterate(iterator, (void**)&child_sa))
 116         {
 117                 switch (child_sa->get_state(child_sa))
 118                 {
 119                         case CHILD_CREATED:
 120                         case CHILD_REKEYING:
 121                         case CHILD_DELETING:
 122                                 /* we do not allow rekeying while we have children in-progress */
 123                                 DBG1(DBG_IKE, "peer initiated rekeying, but a child is half-open");
 124                                 iterator->destroy(iterator);
 125                                 return NEED_MORE;
 126                         default:
 127                                 break;
 128                 }
 129         }
 130         iterator->destroy(iterator);
 131
 132         id = ike_sa_id_create(0, 0, FALSE);
 133         this->new_sa = charon->ike_sa_manager->checkout(charon->ike_sa_manager, id);
 134         id->destroy(id);
 135
 136         connection = this->ike_sa->get_connection(this->ike_sa);
 137         policy = this->ike_sa->get_policy(this->ike_sa);
 138         this->new_sa->set_connection(this->new_sa, connection);
 139         this->new_sa->set_policy(this->new_sa, policy);
 140
 141         this->ike_init = ike_init_create(this->new_sa, FALSE, this->ike_sa);
 142         this->ike_init->task.process(&this->ike_init->task, message);
 143
 144         return NEED_MORE;
 145 }
 146
 147 /**
 148  * Implementation of task_t.build for responder
 149  */
 150 static status_t build_r(private_ike_rekey_t *this, message_t *message)
 151 {
 152         if (this->new_sa == NULL)
 153         {
 154                 /* IKE_SA/a CHILD_SA is in an inacceptable state, deny rekeying */
 155                 message->add_notify(message, TRUE, NO_PROPOSAL_CHOSEN, chunk_empty);
 156                 return SUCCESS;
 157         }
 158
 159         if (this->ike_init->task.build(&this->ike_init->task, message) == FAILED)
 160         {
 161                 return SUCCESS;
 162         }
 163
 164         this->ike_sa->set_state(this->ike_sa, IKE_REKEYING);
 165         this->new_sa->set_state(this->new_sa, IKE_ESTABLISHED);
 166
 167         return SUCCESS;
 168 }
 169
 170 /**
 171  * Implementation of task_t.process for initiator
 172  */
 173 static status_t process_i(private_ike_rekey_t *this, message_t *message)
 174 {
 175         job_t *job;
 176         ike_sa_id_t *to_delete;
 177
 178         if (this->ike_init->task.process(&this->ike_init->task, message) == FAILED)
 179         {
 180                 /* rekeying failed, fallback to old SA */
 181                 if (!(this->collision &&
 182                         this->collision->get_type(this->collision) == IKE_DELETE))
 183                 {
 184                         job_t *job;
 185                         u_int32_t retry = charon->configuration->get_retry_interval(
 186                                                                         charon->configuration);
 187                         job = (job_t*)rekey_ike_sa_job_create(
 188                                                                         this->ike_sa->get_id(this->ike_sa), FALSE);
 189                         DBG1(DBG_IKE, "IKE_SA rekeying failed, "
 190                                                                         "trying again in %d seconds", retry);
 191                         this->ike_sa->set_state(this->ike_sa, IKE_ESTABLISHED);
 192                         charon->event_queue->add_relative(charon->event_queue, job, retry * 1000);
 193                 }
 194                 return SUCCESS;
 195         }
 196
 197         this->new_sa->set_state(this->new_sa, IKE_ESTABLISHED);
 198         to_delete = this->ike_sa->get_id(this->ike_sa);
 199
 200         /* check for collisions */
 201         if (this->collision &&
 202                 this->collision->get_type(this->collision) == IKE_REKEY)
 203         {
 204                 chunk_t this_nonce, other_nonce;
 205                 host_t *host;
 206                 private_ike_rekey_t *other = (private_ike_rekey_t*)this->collision;
 207
 208                 this_nonce = this->ike_init->get_lower_nonce(this->ike_init);
 209                 other_nonce = other->ike_init->get_lower_nonce(other->ike_init);
 210
 211                 /* if we have the lower nonce, delete rekeyed SA. If not, delete
 212                  * the redundant. */
 213                 if (memcmp(this_nonce.ptr, other_nonce.ptr,
 214                                    min(this_nonce.len, other_nonce.len)) < 0)
 215                 {
 216                         DBG1(DBG_IKE, "IKE_SA rekey collision won, deleting rekeyed IKE_SA");
 217                         charon->ike_sa_manager->checkin(charon->ike_sa_manager, other->new_sa);
 218                 }
 219                 else
 220                 {
 221                         DBG1(DBG_IKE, "IKE_SA rekey collision lost, deleting redundant IKE_SA");
 222                         /* apply host for a proper delete */
 223                         host = this->ike_sa->get_my_host(this->ike_sa);
 224                         this->new_sa->set_my_host(this->new_sa, host->clone(host));
 225                         host = this->ike_sa->get_other_host(this->ike_sa);
 226                         this->new_sa->set_other_host(this->new_sa, host->clone(host));
 227                         this->ike_sa->set_state(this->ike_sa, IKE_ESTABLISHED);
 228                         to_delete = this->new_sa->get_id(this->new_sa);
 229                         charon->ike_sa_manager->checkin(charon->ike_sa_manager, this->new_sa);
 230                         /* inherit to other->new_sa in destroy() */
 231                         this->new_sa = other->new_sa;
 232                         other->new_sa = NULL;
 233                 }
 234         }
 235
 236         job = (job_t*)delete_ike_sa_job_create(to_delete, TRUE);
 237         charon->job_queue->add(charon->job_queue, job);
 238
 239         return SUCCESS;
 240 }
 241
 242 /**
 243  * Implementation of task_t.get_type
 244  */
 245 static task_type_t get_type(private_ike_rekey_t *this)
 246 {
 247         return IKE_REKEY;
 248 }
 249
 250 static void collide(private_ike_rekey_t* this, task_t *other)
 251 {
 252         DESTROY_IF(this->collision);
 253         this->collision = other;
 254 }
 255
 256 /**
 257  * Implementation of task_t.migrate
 258  */
 259 static void migrate(private_ike_rekey_t *this, ike_sa_t *ike_sa)
 260 {
 261         if (this->ike_init)
 262         {
 263                 this->ike_init->task.destroy(&this->ike_init->task);
 264         }
 265         if (this->new_sa)
 266         {
 267                 charon->ike_sa_manager->checkin_and_destroy(charon->ike_sa_manager,
 268                                                                                                         this->new_sa);
 269         }
 270         DESTROY_IF(this->collision);
 271
 272         this->collision = NULL;
 273         this->ike_sa = ike_sa;
 274         this->new_sa = NULL;
 275         this->ike_init = NULL;
 276 }
 277
 278 /**
 279  * Implementation of task_t.destroy
 280  */
 281 static void destroy(private_ike_rekey_t *this)
 282 {
 283         if (this->new_sa)
 284         {
 285                 if (this->new_sa->get_state(this->new_sa) == IKE_ESTABLISHED)
 286                 {
 287                         this->new_sa->inherit(this->new_sa, this->ike_sa);
 288                         charon->ike_sa_manager->checkin(charon->ike_sa_manager, this->new_sa);
 289                 }
 290                 else
 291                 {
 292                         charon->ike_sa_manager->checkin_and_destroy(charon->ike_sa_manager,
 293                                                                                                                 this->new_sa);
 294                 }
 295         }
 296         if (this->ike_init)
 297         {
 298                 this->ike_init->task.destroy(&this->ike_init->task);
 299         }
 300         DESTROY_IF(this->collision);
 301         free(this);
 302 }
 303
 304 /*
 305  * Described in header.
 306  */
 307 ike_rekey_t *ike_rekey_create(ike_sa_t *ike_sa, bool initiator)
 308 {
 309         private_ike_rekey_t *this = malloc_thing(private_ike_rekey_t);
 310
 311         this->public.collide = (void(*)(ike_rekey_t*,task_t*))collide;
 312         this->public.task.get_type = (task_type_t(*)(task_t*))get_type;
 313         this->public.task.migrate = (void(*)(task_t*,ike_sa_t*))migrate;
 314         this->public.task.destroy = (void(*)(task_t*))destroy;
 315         if (initiator)
 316         {
 317                 this->public.task.build = (status_t(*)(task_t*,message_t*))build_i;
 318                 this->public.task.process = (status_t(*)(task_t*,message_t*))process_i;
 319         }
 320         else
 321         {
 322                 this->public.task.build = (status_t(*)(task_t*,message_t*))build_r;
 323                 this->public.task.process = (status_t(*)(task_t*,message_t*))process_r;
 324         }
 325
 326         this->ike_sa = ike_sa;
 327         this->new_sa = NULL;
 328         this->ike_init = NULL;
 329         this->initiator = initiator;
 330         this->collision = NULL;
 331
 332         return &this->public;
 333 }