src/libcharon/sa/ikev2/tasks/ike_rekey.c

   1 /*
   2  * Copyright (C) 2005-2008 Martin Willi
   3  * Copyright (C) 2005 Jan Hutter
   4  * Hochschule fuer Technik Rapperswil
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License as published by the
   8  * Free Software Foundation; either version 2 of the License, or (at your
   9  * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
  10  *
  11  * This program is distributed in the hope that it will be useful, but
  12  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  13  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * for more details.
  15  */
  16
  17 #include "ike_rekey.h"
  18
  19 #include <daemon.h>
  20 #include <encoding/payloads/notify_payload.h>
  21 #include <sa/ikev2/tasks/ike_init.h>
  22 #include <sa/ikev2/tasks/ike_delete.h>
  23 #include <processing/jobs/delete_ike_sa_job.h>
  24 #include <processing/jobs/rekey_ike_sa_job.h>
  25
  26
  27 typedef struct private_ike_rekey_t private_ike_rekey_t;
  28
  29 /**
  30  * Private members of a ike_rekey_t task.
  31  */
  32 struct private_ike_rekey_t {
  33
  34         /**
  35          * Public methods and task_t interface.
  36          */
  37         ike_rekey_t public;
  38
  39         /**
  40          * Assigned IKE_SA.
  41          */
  42         ike_sa_t *ike_sa;
  43
  44         /**
  45          * New IKE_SA which replaces the current one
  46          */
  47         ike_sa_t *new_sa;
  48
  49         /**
  50          * Are we the initiator?
  51          */
  52         bool initiator;
  53
  54         /**
  55          * the TASK_IKE_INIT task which is reused to simplify rekeying
  56          */
  57         ike_init_t *ike_init;
  58
  59         /**
  60          * IKE_DELETE task to delete the old IKE_SA after rekeying was successful
  61          */
  62         ike_delete_t *ike_delete;
  63
  64         /**
  65          * colliding task detected by the task manager
  66          */
  67         task_t *collision;
  68 };
  69
  70 /**
  71  * Establish the new replacement IKE_SA
  72  */
  73 static void establish_new(private_ike_rekey_t *this)
  74 {
  75         if (this->new_sa)
  76         {
  77                 this->new_sa->set_state(this->new_sa, IKE_ESTABLISHED);
  78                 DBG0(DBG_IKE, "IKE_SA %s[%d] rekeyed between %H[%Y]...%H[%Y]",
  79                          this->new_sa->get_name(this->new_sa),
  80                          this->new_sa->get_unique_id(this->new_sa),
  81                          this->ike_sa->get_my_host(this->ike_sa),
  82                          this->ike_sa->get_my_id(this->ike_sa),
  83                          this->ike_sa->get_other_host(this->ike_sa),
  84                          this->ike_sa->get_other_id(this->ike_sa));
  85
  86                 this->new_sa->inherit(this->new_sa, this->ike_sa);
  87                 charon->bus->ike_rekey(charon->bus, this->ike_sa, this->new_sa);
  88                 charon->ike_sa_manager->checkin(charon->ike_sa_manager, this->new_sa);
  89                 this->new_sa = NULL;
  90                 /* set threads active IKE_SA after checkin */
  91                 charon->bus->set_sa(charon->bus, this->ike_sa);
  92         }
  93 }
  94
  95 METHOD(task_t, process_r_delete, status_t,
  96         private_ike_rekey_t *this, message_t *message)
  97 {
  98         establish_new(this);
  99         return this->ike_delete->task.process(&this->ike_delete->task, message);
 100 }
 101
 102 METHOD(task_t, build_r_delete, status_t,
 103         private_ike_rekey_t *this, message_t *message)
 104 {
 105         return this->ike_delete->task.build(&this->ike_delete->task, message);
 106 }
 107
 108 METHOD(task_t, build_i_delete, status_t,
 109         private_ike_rekey_t *this, message_t *message)
 110 {
 111         /* update exchange type to INFORMATIONAL for the delete */
 112         message->set_exchange_type(message, INFORMATIONAL);
 113
 114         return this->ike_delete->task.build(&this->ike_delete->task, message);
 115 }
 116
 117 METHOD(task_t, process_i_delete, status_t,
 118         private_ike_rekey_t *this, message_t *message)
 119 {
 120         return this->ike_delete->task.process(&this->ike_delete->task, message);
 121 }
 122
 123 METHOD(task_t, build_i, status_t,
 124         private_ike_rekey_t *this, message_t *message)
 125 {
 126         peer_cfg_t *peer_cfg;
 127         host_t *other_host;
 128
 129         /* create new SA only on first try */
 130         if (this->new_sa == NULL)
 131         {
 132                 ike_version_t version = this->ike_sa->get_version(this->ike_sa);
 133                 this->new_sa = charon->ike_sa_manager->checkout_new(
 134                                                                                 charon->ike_sa_manager, version, TRUE);
 135
 136                 peer_cfg = this->ike_sa->get_peer_cfg(this->ike_sa);
 137                 other_host = this->ike_sa->get_other_host(this->ike_sa);
 138                 this->new_sa->set_peer_cfg(this->new_sa, peer_cfg);
 139                 this->new_sa->set_other_host(this->new_sa, other_host->clone(other_host));
 140                 this->ike_init = ike_init_create(this->new_sa, TRUE, this->ike_sa);
 141                 this->ike_sa->set_state(this->ike_sa, IKE_REKEYING);
 142         }
 143         this->ike_init->task.build(&this->ike_init->task, message);
 144
 145         return NEED_MORE;
 146 }
 147
 148 METHOD(task_t, process_r, status_t,
 149         private_ike_rekey_t *this, message_t *message)
 150 {
 151         enumerator_t *enumerator;
 152         ike_version_t version;
 153         peer_cfg_t *peer_cfg;
 154         child_sa_t *child_sa;
 155
 156         if (this->ike_sa->get_state(this->ike_sa) == IKE_DELETING)
 157         {
 158                 DBG1(DBG_IKE, "peer initiated rekeying, but we are deleting");
 159                 return NEED_MORE;
 160         }
 161
 162         enumerator = this->ike_sa->create_child_sa_enumerator(this->ike_sa);
 163         while (enumerator->enumerate(enumerator, (void**)&child_sa))
 164         {
 165                 switch (child_sa->get_state(child_sa))
 166                 {
 167                         case CHILD_CREATED:
 168                         case CHILD_REKEYING:
 169                         case CHILD_DELETING:
 170                                 /* we do not allow rekeying while we have children in-progress */
 171                                 DBG1(DBG_IKE, "peer initiated rekeying, but a child is half-open");
 172                                 enumerator->destroy(enumerator);
 173                                 return NEED_MORE;
 174                         default:
 175                                 break;
 176                 }
 177         }
 178         enumerator->destroy(enumerator);
 179
 180         version = this->ike_sa->get_version(this->ike_sa);
 181         this->new_sa = charon->ike_sa_manager->checkout_new(charon->ike_sa_manager,
 182                                                                                                                 version, FALSE);
 183
 184         peer_cfg = this->ike_sa->get_peer_cfg(this->ike_sa);
 185         this->new_sa->set_peer_cfg(this->new_sa, peer_cfg);
 186         this->ike_init = ike_init_create(this->new_sa, FALSE, this->ike_sa);
 187         this->ike_init->task.process(&this->ike_init->task, message);
 188
 189         return NEED_MORE;
 190 }
 191
 192 METHOD(task_t, build_r, status_t,
 193         private_ike_rekey_t *this, message_t *message)
 194 {
 195         if (this->new_sa == NULL)
 196         {
 197                 /* IKE_SA/a CHILD_SA is in an inacceptable state, deny rekeying */
 198                 message->add_notify(message, TRUE, NO_PROPOSAL_CHOSEN, chunk_empty);
 199                 return SUCCESS;
 200         }
 201
 202         if (this->ike_init->task.build(&this->ike_init->task, message) == FAILED)
 203         {
 204                 return SUCCESS;
 205         }
 206
 207         this->ike_sa->set_state(this->ike_sa, IKE_REKEYING);
 208
 209         /* rekeying successful, delete the IKE_SA using a subtask */
 210         this->ike_delete = ike_delete_create(this->ike_sa, FALSE);
 211         this->public.task.build = _build_r_delete;
 212         this->public.task.process = _process_r_delete;
 213
 214         return NEED_MORE;
 215 }
 216
 217 METHOD(task_t, process_i, status_t,
 218         private_ike_rekey_t *this, message_t *message)
 219 {
 220         if (message->get_notify(message, NO_ADDITIONAL_SAS))
 221         {
 222                 DBG1(DBG_IKE, "peer seems to not support IKE rekeying, "
 223                          "starting reauthentication");
 224                 this->ike_sa->set_state(this->ike_sa, IKE_ESTABLISHED);
 225                 lib->processor->queue_job(lib->processor,
 226                                 (job_t*)rekey_ike_sa_job_create(
 227                                                         this->ike_sa->get_id(this->ike_sa), TRUE));
 228                 return SUCCESS;
 229         }
 230
 231         switch (this->ike_init->task.process(&this->ike_init->task, message))
 232         {
 233                 case FAILED:
 234                         /* rekeying failed, fallback to old SA */
 235                         if (!(this->collision && (
 236                                 this->collision->get_type(this->collision) == TASK_IKE_DELETE ||
 237                                 this->collision->get_type(this->collision) == TASK_IKE_REAUTH)))
 238                         {
 239                                 job_t *job;
 240                                 u_int32_t retry = RETRY_INTERVAL - (random() % RETRY_JITTER);
 241                                 job = (job_t*)rekey_ike_sa_job_create(
 242                                                                                 this->ike_sa->get_id(this->ike_sa), FALSE);
 243                                 DBG1(DBG_IKE, "IKE_SA rekeying failed, "
 244                                                                                 "trying again in %d seconds", retry);
 245                                 this->ike_sa->set_state(this->ike_sa, IKE_ESTABLISHED);
 246                                 lib->scheduler->schedule_job(lib->scheduler, job, retry);
 247                         }
 248                         return SUCCESS;
 249                 case NEED_MORE:
 250                         /* bad dh group, try again */
 251                         this->ike_init->task.migrate(&this->ike_init->task, this->new_sa);
 252                         return NEED_MORE;
 253                 default:
 254                         break;
 255         }
 256
 257         /* check for collisions */
 258         if (this->collision &&
 259                 this->collision->get_type(this->collision) == TASK_IKE_REKEY)
 260         {
 261                 private_ike_rekey_t *other = (private_ike_rekey_t*)this->collision;
 262
 263                 /* ike_init can be NULL, if child_sa is half-open */
 264                 if (other->ike_init)
 265                 {
 266                         host_t *host;
 267                         chunk_t this_nonce, other_nonce;
 268
 269                         this_nonce = this->ike_init->get_lower_nonce(this->ike_init);
 270                         other_nonce = other->ike_init->get_lower_nonce(other->ike_init);
 271
 272                         /* if we have the lower nonce, delete rekeyed SA. If not, delete
 273                          * the redundant. */
 274                         if (memcmp(this_nonce.ptr, other_nonce.ptr,
 275                                                 min(this_nonce.len, other_nonce.len)) > 0)
 276                         {
 277                                 /* peer should delete this SA. Add a timeout just in case. */
 278                                 job_t *job = (job_t*)delete_ike_sa_job_create(
 279                                                 other->new_sa->get_id(other->new_sa), TRUE);
 280                                 lib->scheduler->schedule_job(lib->scheduler, job, 10);
 281                                 DBG1(DBG_IKE, "IKE_SA rekey collision won, waiting for delete");
 282                                 charon->ike_sa_manager->checkin(charon->ike_sa_manager, other->new_sa);
 283                                 other->new_sa = NULL;
 284                         }
 285                         else
 286                         {
 287                                 DBG1(DBG_IKE, "IKE_SA rekey collision lost, "
 288                                          "deleting redundant IKE_SA");
 289                                 /* apply host for a proper delete */
 290                                 host = this->ike_sa->get_my_host(this->ike_sa);
 291                                 this->new_sa->set_my_host(this->new_sa, host->clone(host));
 292                                 host = this->ike_sa->get_other_host(this->ike_sa);
 293                                 this->new_sa->set_other_host(this->new_sa, host->clone(host));
 294                                 this->ike_sa->set_state(this->ike_sa, IKE_ESTABLISHED);
 295                                 this->new_sa->set_state(this->new_sa, IKE_REKEYING);
 296                                 if (this->new_sa->delete(this->new_sa) == DESTROY_ME)
 297                                 {
 298                                         this->new_sa->destroy(this->new_sa);
 299                                 }
 300                                 else
 301                                 {
 302                                         charon->ike_sa_manager->checkin(
 303                                                                 charon->ike_sa_manager, this->new_sa);
 304                                         /* set threads active IKE_SA after checkin */
 305                                         charon->bus->set_sa(charon->bus, this->ike_sa);
 306                                 }
 307                                 this->new_sa = NULL;
 308                                 establish_new(other);
 309                                 return SUCCESS;
 310                         }
 311                 }
 312                 /* set threads active IKE_SA after checkin */
 313                 charon->bus->set_sa(charon->bus, this->ike_sa);
 314         }
 315
 316         establish_new(this);
 317
 318         /* rekeying successful, delete the IKE_SA using a subtask */
 319         this->ike_delete = ike_delete_create(this->ike_sa, TRUE);
 320         this->public.task.build = _build_i_delete;
 321         this->public.task.process = _process_i_delete;
 322
 323         return NEED_MORE;
 324 }
 325
 326 METHOD(task_t, get_type, task_type_t,
 327         private_ike_rekey_t *this)
 328 {
 329         return TASK_IKE_REKEY;
 330 }
 331
 332 METHOD(ike_rekey_t, collide, void,
 333         private_ike_rekey_t* this, task_t *other)
 334 {
 335         DBG1(DBG_IKE, "detected %N collision with %N", task_type_names,
 336                  TASK_IKE_REKEY, task_type_names, other->get_type(other));
 337         DESTROY_IF(this->collision);
 338         this->collision = other;
 339 }
 340
 341 METHOD(task_t, migrate, void,
 342         private_ike_rekey_t *this, ike_sa_t *ike_sa)
 343 {
 344         if (this->ike_init)
 345         {
 346                 this->ike_init->task.destroy(&this->ike_init->task);
 347         }
 348         if (this->ike_delete)
 349         {
 350                 this->ike_delete->task.destroy(&this->ike_delete->task);
 351         }
 352         DESTROY_IF(this->new_sa);
 353         DESTROY_IF(this->collision);
 354
 355         this->collision = NULL;
 356         this->ike_sa = ike_sa;
 357         this->new_sa = NULL;
 358         this->ike_init = NULL;
 359         this->ike_delete = NULL;
 360 }
 361
 362 METHOD(task_t, destroy, void,
 363         private_ike_rekey_t *this)
 364 {
 365         if (this->ike_init)
 366         {
 367                 this->ike_init->task.destroy(&this->ike_init->task);
 368         }
 369         if (this->ike_delete)
 370         {
 371                 this->ike_delete->task.destroy(&this->ike_delete->task);
 372         }
 373         DESTROY_IF(this->new_sa);
 374         DESTROY_IF(this->collision);
 375         free(this);
 376 }
 377
 378 /*
 379  * Described in header.
 380  */
 381 ike_rekey_t *ike_rekey_create(ike_sa_t *ike_sa, bool initiator)
 382 {
 383         private_ike_rekey_t *this;
 384
 385         INIT(this,
 386                 .public = {
 387                         .task = {
 388                                 .get_type = _get_type,
 389                                 .build = _build_r,
 390                                 .process = _process_r,
 391                                 .migrate = _migrate,
 392                                 .destroy = _destroy,
 393                         },
 394                         .collide = _collide,
 395                 },
 396                 .ike_sa = ike_sa,
 397                 .initiator = initiator,
 398         );
 399         if (initiator)
 400         {
 401                 this->public.task.build = _build_i;
 402                 this->public.task.process = _process_i;
 403         }
 404
 405         return &this->public;
 406 }