ike-rekey: Register new IKE_SA before calling inherit_post()
[strongswan.git] / src / libcharon / sa / ikev2 / tasks / ike_rekey.c
1 /*
2 * Copyright (C) 2015-2016 Tobias Brunner
3 * Copyright (C) 2005-2008 Martin Willi
4 * Copyright (C) 2005 Jan Hutter
5 * HSR Hochschule fuer Technik Rapperswil
6 *
7 * This program is free software; you can redistribute it and/or modify it
8 * under the terms of the GNU General Public License as published by the
9 * Free Software Foundation; either version 2 of the License, or (at your
10 * option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>.
11 *
12 * This program is distributed in the hope that it will be useful, but
13 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
14 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15 * for more details.
16 */
17
18 #include "ike_rekey.h"
19
20 #include <daemon.h>
21 #include <encoding/payloads/notify_payload.h>
22 #include <sa/ikev2/tasks/ike_init.h>
23 #include <sa/ikev2/tasks/ike_delete.h>
24 #include <processing/jobs/delete_ike_sa_job.h>
25 #include <processing/jobs/rekey_ike_sa_job.h>
26 #include <processing/jobs/initiate_tasks_job.h>
27
28
29 typedef struct private_ike_rekey_t private_ike_rekey_t;
30
31 /**
32 * Private members of a ike_rekey_t task.
33 */
34 struct private_ike_rekey_t {
35
36 /**
37 * Public methods and task_t interface.
38 */
39 ike_rekey_t public;
40
41 /**
42 * Assigned IKE_SA.
43 */
44 ike_sa_t *ike_sa;
45
46 /**
47 * New IKE_SA which replaces the current one
48 */
49 ike_sa_t *new_sa;
50
51 /**
52 * Are we the initiator?
53 */
54 bool initiator;
55
56 /**
57 * the TASK_IKE_INIT task which is reused to simplify rekeying
58 */
59 ike_init_t *ike_init;
60
61 /**
62 * IKE_DELETE task to delete the old IKE_SA after rekeying was successful
63 */
64 ike_delete_t *ike_delete;
65
66 /**
67 * colliding task detected by the task manager
68 */
69 task_t *collision;
70
71 /**
72 * TRUE if rekeying can't be handled temporarily
73 */
74 bool failed_temporarily;
75 };
76
77 /**
78 * Schedule a retry if rekeying temporary failed
79 */
80 static void schedule_delayed_rekey(private_ike_rekey_t *this)
81 {
82 uint32_t retry;
83 job_t *job;
84
85 retry = RETRY_INTERVAL - (random() % RETRY_JITTER);
86 job = (job_t*)rekey_ike_sa_job_create(
87 this->ike_sa->get_id(this->ike_sa), FALSE);
88 DBG1(DBG_IKE, "IKE_SA rekeying failed, trying again in %d seconds", retry);
89 this->ike_sa->set_state(this->ike_sa, IKE_ESTABLISHED);
90 lib->scheduler->schedule_job(lib->scheduler, job, retry);
91 }
92
93 /**
94 * Check if an IKE_SA has any queued tasks, return initiation job
95 */
96 static job_t* check_queued_tasks(ike_sa_t *ike_sa)
97 {
98 enumerator_t *enumerator;
99 task_t *task;
100 job_t *job = NULL;
101
102 enumerator = ike_sa->create_task_enumerator(ike_sa, TASK_QUEUE_QUEUED);
103 if (enumerator->enumerate(enumerator, &task))
104 {
105 job = (job_t*)initiate_tasks_job_create(ike_sa->get_id(ike_sa));
106 }
107 enumerator->destroy(enumerator);
108 return job;
109 }
110
111 /**
112 * Establish the new replacement IKE_SA
113 */
114 static void establish_new(private_ike_rekey_t *this)
115 {
116 if (this->new_sa)
117 {
118 job_t *job;
119
120 this->new_sa->set_state(this->new_sa, IKE_ESTABLISHED);
121 DBG0(DBG_IKE, "IKE_SA %s[%d] rekeyed between %H[%Y]...%H[%Y]",
122 this->new_sa->get_name(this->new_sa),
123 this->new_sa->get_unique_id(this->new_sa),
124 this->ike_sa->get_my_host(this->ike_sa),
125 this->ike_sa->get_my_id(this->ike_sa),
126 this->ike_sa->get_other_host(this->ike_sa),
127 this->ike_sa->get_other_id(this->ike_sa));
128
129 /* register the new IKE_SA before calling inherit_post() as that may
130 * schedule jobs, as may listeners for ike_rekey() */
131 charon->ike_sa_manager->checkout_new(charon->ike_sa_manager,
132 this->new_sa);
133 this->new_sa->inherit_post(this->new_sa, this->ike_sa);
134 charon->bus->ike_rekey(charon->bus, this->ike_sa, this->new_sa);
135 job = check_queued_tasks(this->new_sa);
136 if (job)
137 {
138 lib->processor->queue_job(lib->processor, job);
139 }
140 charon->ike_sa_manager->checkin(charon->ike_sa_manager, this->new_sa);
141 this->new_sa = NULL;
142 charon->bus->set_sa(charon->bus, this->ike_sa);
143
144 this->ike_sa->set_state(this->ike_sa, IKE_REKEYED);
145 }
146 }
147
148 METHOD(task_t, build_i_delete, status_t,
149 private_ike_rekey_t *this, message_t *message)
150 {
151 /* update exchange type to INFORMATIONAL for the delete */
152 message->set_exchange_type(message, INFORMATIONAL);
153
154 return this->ike_delete->task.build(&this->ike_delete->task, message);
155 }
156
157 METHOD(task_t, process_i_delete, status_t,
158 private_ike_rekey_t *this, message_t *message)
159 {
160 return this->ike_delete->task.process(&this->ike_delete->task, message);
161 }
162
163 METHOD(task_t, build_i, status_t,
164 private_ike_rekey_t *this, message_t *message)
165 {
166 ike_version_t version;
167
168 /* create new SA only on first try */
169 if (this->new_sa == NULL)
170 {
171 version = this->ike_sa->get_version(this->ike_sa);
172 this->new_sa = charon->ike_sa_manager->create_new(
173 charon->ike_sa_manager, version, TRUE);
174 if (!this->new_sa)
175 { /* shouldn't happen */
176 return FAILED;
177 }
178 this->new_sa->inherit_pre(this->new_sa, this->ike_sa);
179 this->ike_init = ike_init_create(this->new_sa, TRUE, this->ike_sa);
180 this->ike_sa->set_state(this->ike_sa, IKE_REKEYING);
181 }
182 this->ike_init->task.build(&this->ike_init->task, message);
183
184 return NEED_MORE;
185 }
186
187 /**
188 * Check if there are any half-open children
189 */
190 static bool have_half_open_children(private_ike_rekey_t *this)
191 {
192 enumerator_t *enumerator;
193 child_sa_t *child_sa;
194 task_t *task;
195
196 enumerator = this->ike_sa->create_child_sa_enumerator(this->ike_sa);
197 while (enumerator->enumerate(enumerator, (void**)&child_sa))
198 {
199 switch (child_sa->get_state(child_sa))
200 {
201 case CHILD_REKEYING:
202 case CHILD_RETRYING:
203 case CHILD_DELETING:
204 enumerator->destroy(enumerator);
205 return TRUE;
206 default:
207 break;
208 }
209 }
210 enumerator->destroy(enumerator);
211 enumerator = this->ike_sa->create_task_enumerator(this->ike_sa,
212 TASK_QUEUE_ACTIVE);
213 while (enumerator->enumerate(enumerator, (void**)&task))
214 {
215 if (task->get_type(task) == TASK_CHILD_CREATE)
216 {
217 enumerator->destroy(enumerator);
218 return TRUE;
219 }
220 }
221 enumerator->destroy(enumerator);
222 return FALSE;
223 }
224
225 METHOD(task_t, process_r, status_t,
226 private_ike_rekey_t *this, message_t *message)
227 {
228 if (this->ike_sa->get_state(this->ike_sa) == IKE_DELETING)
229 {
230 DBG1(DBG_IKE, "peer initiated rekeying, but we are deleting");
231 this->failed_temporarily = TRUE;
232 return NEED_MORE;
233 }
234 if (have_half_open_children(this))
235 {
236 DBG1(DBG_IKE, "peer initiated rekeying, but a child is half-open");
237 this->failed_temporarily = TRUE;
238 return NEED_MORE;
239 }
240
241 this->new_sa = charon->ike_sa_manager->create_new(charon->ike_sa_manager,
242 this->ike_sa->get_version(this->ike_sa), FALSE);
243 if (!this->new_sa)
244 { /* shouldn't happen */
245 return FAILED;
246 }
247 this->new_sa->inherit_pre(this->new_sa, this->ike_sa);
248 this->ike_init = ike_init_create(this->new_sa, FALSE, this->ike_sa);
249 this->ike_init->task.process(&this->ike_init->task, message);
250
251 return NEED_MORE;
252 }
253
254 METHOD(task_t, build_r, status_t,
255 private_ike_rekey_t *this, message_t *message)
256 {
257 if (this->failed_temporarily)
258 {
259 message->add_notify(message, TRUE, TEMPORARY_FAILURE, chunk_empty);
260 return SUCCESS;
261 }
262 if (this->new_sa == NULL)
263 {
264 /* IKE_SA/a CHILD_SA is in an unacceptable state, deny rekeying */
265 message->add_notify(message, TRUE, NO_PROPOSAL_CHOSEN, chunk_empty);
266 return SUCCESS;
267 }
268 if (this->ike_init->task.build(&this->ike_init->task, message) == FAILED)
269 {
270 this->ike_init->task.destroy(&this->ike_init->task);
271 this->ike_init = NULL;
272 charon->bus->set_sa(charon->bus, this->ike_sa);
273 return SUCCESS;
274 }
275 charon->bus->set_sa(charon->bus, this->ike_sa);
276
277 if (this->ike_sa->get_state(this->ike_sa) != IKE_REKEYING)
278 { /* in case of a collision we let the initiating task handle this */
279 establish_new(this);
280 /* make sure the IKE_SA is gone in case the peer fails to delete it */
281 lib->scheduler->schedule_job(lib->scheduler, (job_t*)
282 delete_ike_sa_job_create(this->ike_sa->get_id(this->ike_sa), TRUE),
283 90);
284 }
285 return SUCCESS;
286 }
287
288 /**
289 * Conclude any undetected rekey collision.
290 *
291 * If the peer does not detect the collision it will delete this IKE_SA.
292 * Depending on when our request reaches the peer and we receive the delete
293 * this may get called at different times.
294 *
295 * Returns TRUE if there was a collision, FALSE otherwise.
296 */
297 static bool conclude_undetected_collision(private_ike_rekey_t *this)
298 {
299 if (this->collision &&
300 this->collision->get_type(this->collision) == TASK_IKE_REKEY)
301 {
302 DBG1(DBG_IKE, "peer did not notice IKE_SA rekey collision, abort "
303 "active rekeying");
304 establish_new((private_ike_rekey_t*)this->collision);
305 return TRUE;
306 }
307 return FALSE;
308 }
309
310 METHOD(task_t, process_i, status_t,
311 private_ike_rekey_t *this, message_t *message)
312 {
313 if (message->get_notify(message, NO_ADDITIONAL_SAS))
314 {
315 DBG1(DBG_IKE, "peer seems to not support IKE rekeying, "
316 "starting reauthentication");
317 this->ike_sa->set_state(this->ike_sa, IKE_ESTABLISHED);
318 lib->processor->queue_job(lib->processor,
319 (job_t*)rekey_ike_sa_job_create(
320 this->ike_sa->get_id(this->ike_sa), TRUE));
321 return SUCCESS;
322 }
323
324 switch (this->ike_init->task.process(&this->ike_init->task, message))
325 {
326 case FAILED:
327 /* rekeying failed, fallback to old SA */
328 if (!conclude_undetected_collision(this))
329 {
330 schedule_delayed_rekey(this);
331 }
332 return SUCCESS;
333 case NEED_MORE:
334 /* bad dh group, try again */
335 this->ike_init->task.migrate(&this->ike_init->task, this->new_sa);
336 return NEED_MORE;
337 default:
338 break;
339 }
340
341 /* check for collisions */
342 if (this->collision &&
343 this->collision->get_type(this->collision) == TASK_IKE_REKEY)
344 {
345 private_ike_rekey_t *other = (private_ike_rekey_t*)this->collision;
346 host_t *host;
347 chunk_t this_nonce, other_nonce;
348
349 this_nonce = this->ike_init->get_lower_nonce(this->ike_init);
350 other_nonce = other->ike_init->get_lower_nonce(other->ike_init);
351
352 /* if we have the lower nonce, delete rekeyed SA. If not, delete
353 * the redundant. */
354 if (memcmp(this_nonce.ptr, other_nonce.ptr,
355 min(this_nonce.len, other_nonce.len)) < 0)
356 {
357 DBG1(DBG_IKE, "IKE_SA rekey collision lost, deleting redundant "
358 "IKE_SA %s[%d]", this->new_sa->get_name(this->new_sa),
359 this->new_sa->get_unique_id(this->new_sa));
360 /* apply host for a proper delete */
361 host = this->ike_sa->get_my_host(this->ike_sa);
362 this->new_sa->set_my_host(this->new_sa, host->clone(host));
363 host = this->ike_sa->get_other_host(this->ike_sa);
364 this->new_sa->set_other_host(this->new_sa, host->clone(host));
365 /* IKE_SAs in state IKE_REKEYED are silently deleted, so we use
366 * IKE_REKEYING */
367 this->new_sa->set_state(this->new_sa, IKE_REKEYING);
368 if (this->new_sa->delete(this->new_sa, FALSE) == DESTROY_ME)
369 {
370 this->new_sa->destroy(this->new_sa);
371 }
372 else
373 {
374 charon->ike_sa_manager->checkin(charon->ike_sa_manager,
375 this->new_sa);
376 }
377 charon->bus->set_sa(charon->bus, this->ike_sa);
378 this->new_sa = NULL;
379 establish_new(other);
380 return SUCCESS;
381 }
382 /* peer should delete this SA. Add a timeout just in case. */
383 job_t *job = (job_t*)delete_ike_sa_job_create(
384 other->new_sa->get_id(other->new_sa), TRUE);
385 lib->scheduler->schedule_job(lib->scheduler, job,
386 HALF_OPEN_IKE_SA_TIMEOUT);
387 DBG1(DBG_IKE, "IKE_SA rekey collision won, waiting for delete for "
388 "redundant IKE_SA %s[%d]", other->new_sa->get_name(other->new_sa),
389 other->new_sa->get_unique_id(other->new_sa));
390 other->new_sa->set_state(other->new_sa, IKE_REKEYED);
391 charon->ike_sa_manager->checkin(charon->ike_sa_manager, other->new_sa);
392 other->new_sa = NULL;
393 charon->bus->set_sa(charon->bus, this->ike_sa);
394 }
395
396 establish_new(this);
397
398 /* rekeying successful, delete the IKE_SA using a subtask */
399 this->ike_delete = ike_delete_create(this->ike_sa, TRUE);
400 this->public.task.build = _build_i_delete;
401 this->public.task.process = _process_i_delete;
402
403 return NEED_MORE;
404 }
405
406 METHOD(task_t, get_type, task_type_t,
407 private_ike_rekey_t *this)
408 {
409 return TASK_IKE_REKEY;
410 }
411
412 METHOD(ike_rekey_t, did_collide, bool,
413 private_ike_rekey_t *this)
414 {
415 return this->collision &&
416 this->collision->get_type(this->collision) == TASK_IKE_REKEY;
417 }
418
419 METHOD(ike_rekey_t, collide, void,
420 private_ike_rekey_t* this, task_t *other)
421 {
422 DBG1(DBG_IKE, "detected %N collision with %N", task_type_names,
423 TASK_IKE_REKEY, task_type_names, other->get_type(other));
424
425 switch (other->get_type(other))
426 {
427 case TASK_IKE_DELETE:
428 conclude_undetected_collision(this);
429 other->destroy(other);
430 return;
431 case TASK_IKE_REKEY:
432 {
433 private_ike_rekey_t *rekey = (private_ike_rekey_t*)other;
434
435 if (!rekey->ike_init)
436 {
437 DBG1(DBG_IKE, "colliding exchange did not result in an IKE_SA, "
438 "ignore");
439 other->destroy(other);
440 return;
441 }
442 break;
443 }
444 default:
445 break;
446 }
447 DESTROY_IF(this->collision);
448 this->collision = other;
449 }
450
451 /**
452 * Cleanup the task
453 */
454 static void cleanup(private_ike_rekey_t *this)
455 {
456 ike_sa_t *cur_sa;
457
458 if (this->ike_init)
459 {
460 this->ike_init->task.destroy(&this->ike_init->task);
461 }
462 if (this->ike_delete)
463 {
464 this->ike_delete->task.destroy(&this->ike_delete->task);
465 }
466 cur_sa = charon->bus->get_sa(charon->bus);
467 DESTROY_IF(this->new_sa);
468 charon->bus->set_sa(charon->bus, cur_sa);
469 DESTROY_IF(this->collision);
470 }
471
472 METHOD(task_t, migrate, void,
473 private_ike_rekey_t *this, ike_sa_t *ike_sa)
474 {
475 cleanup(this);
476 this->collision = NULL;
477 this->ike_sa = ike_sa;
478 this->new_sa = NULL;
479 this->ike_init = NULL;
480 this->ike_delete = NULL;
481 }
482
483 METHOD(task_t, destroy, void,
484 private_ike_rekey_t *this)
485 {
486 cleanup(this);
487 free(this);
488 }
489
490 /*
491 * Described in header.
492 */
493 ike_rekey_t *ike_rekey_create(ike_sa_t *ike_sa, bool initiator)
494 {
495 private_ike_rekey_t *this;
496
497 INIT(this,
498 .public = {
499 .task = {
500 .get_type = _get_type,
501 .build = _build_r,
502 .process = _process_r,
503 .migrate = _migrate,
504 .destroy = _destroy,
505 },
506 .did_collide = _did_collide,
507 .collide = _collide,
508 },
509 .ike_sa = ike_sa,
510 .initiator = initiator,
511 );
512 if (initiator)
513 {
514 this->public.task.build = _build_i;
515 this->public.task.process = _process_i;
516 }
517
518 return &this->public;
519 }