dadf872df0e08f53baacf79d00e77be0400c4ab1
[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 this->new_sa->inherit_post(this->new_sa, this->ike_sa);
130 charon->bus->ike_rekey(charon->bus, this->ike_sa, this->new_sa);
131 job = check_queued_tasks(this->new_sa);
132 /* don't queue job before checkin(), as the IKE_SA is not yet
133 * registered at the manager */
134 charon->ike_sa_manager->checkin(charon->ike_sa_manager, this->new_sa);
135 if (job)
136 {
137 lib->processor->queue_job(lib->processor, job);
138 }
139 this->new_sa = NULL;
140 charon->bus->set_sa(charon->bus, this->ike_sa);
141
142 this->ike_sa->set_state(this->ike_sa, IKE_REKEYED);
143 }
144 }
145
146 METHOD(task_t, build_i_delete, status_t,
147 private_ike_rekey_t *this, message_t *message)
148 {
149 /* update exchange type to INFORMATIONAL for the delete */
150 message->set_exchange_type(message, INFORMATIONAL);
151
152 return this->ike_delete->task.build(&this->ike_delete->task, message);
153 }
154
155 METHOD(task_t, process_i_delete, status_t,
156 private_ike_rekey_t *this, message_t *message)
157 {
158 return this->ike_delete->task.process(&this->ike_delete->task, message);
159 }
160
161 METHOD(task_t, build_i, status_t,
162 private_ike_rekey_t *this, message_t *message)
163 {
164 ike_version_t version;
165
166 /* create new SA only on first try */
167 if (this->new_sa == NULL)
168 {
169 version = this->ike_sa->get_version(this->ike_sa);
170 this->new_sa = charon->ike_sa_manager->checkout_new(
171 charon->ike_sa_manager, version, TRUE);
172 if (!this->new_sa)
173 { /* shouldn't happen */
174 return FAILED;
175 }
176 this->new_sa->inherit_pre(this->new_sa, this->ike_sa);
177 this->ike_init = ike_init_create(this->new_sa, TRUE, this->ike_sa);
178 this->ike_sa->set_state(this->ike_sa, IKE_REKEYING);
179 }
180 this->ike_init->task.build(&this->ike_init->task, message);
181
182 return NEED_MORE;
183 }
184
185 METHOD(task_t, process_r, status_t,
186 private_ike_rekey_t *this, message_t *message)
187 {
188 enumerator_t *enumerator;
189 child_sa_t *child_sa;
190
191 if (this->ike_sa->get_state(this->ike_sa) == IKE_DELETING)
192 {
193 DBG1(DBG_IKE, "peer initiated rekeying, but we are deleting");
194 this->failed_temporarily = TRUE;
195 return NEED_MORE;
196 }
197
198 enumerator = this->ike_sa->create_child_sa_enumerator(this->ike_sa);
199 while (enumerator->enumerate(enumerator, (void**)&child_sa))
200 {
201 switch (child_sa->get_state(child_sa))
202 {
203 case CHILD_CREATED:
204 case CHILD_REKEYING:
205 case CHILD_RETRYING:
206 case CHILD_DELETING:
207 /* we do not allow rekeying while we have children in-progress */
208 DBG1(DBG_IKE, "peer initiated rekeying, but a child is half-open");
209 enumerator->destroy(enumerator);
210 this->failed_temporarily = TRUE;
211 return NEED_MORE;
212 default:
213 break;
214 }
215 }
216 enumerator->destroy(enumerator);
217
218 this->new_sa = charon->ike_sa_manager->checkout_new(charon->ike_sa_manager,
219 this->ike_sa->get_version(this->ike_sa), FALSE);
220 if (!this->new_sa)
221 { /* shouldn't happen */
222 return FAILED;
223 }
224 this->new_sa->inherit_pre(this->new_sa, this->ike_sa);
225 this->ike_init = ike_init_create(this->new_sa, FALSE, this->ike_sa);
226 this->ike_init->task.process(&this->ike_init->task, message);
227
228 return NEED_MORE;
229 }
230
231 METHOD(task_t, build_r, status_t,
232 private_ike_rekey_t *this, message_t *message)
233 {
234 if (this->failed_temporarily)
235 {
236 message->add_notify(message, TRUE, TEMPORARY_FAILURE, chunk_empty);
237 return SUCCESS;
238 }
239 if (this->new_sa == NULL)
240 {
241 /* IKE_SA/a CHILD_SA is in an inacceptable state, deny rekeying */
242 message->add_notify(message, TRUE, NO_PROPOSAL_CHOSEN, chunk_empty);
243 return SUCCESS;
244 }
245
246 if (this->ike_init->task.build(&this->ike_init->task, message) == FAILED)
247 {
248 charon->bus->set_sa(charon->bus, this->ike_sa);
249 return SUCCESS;
250 }
251 charon->bus->set_sa(charon->bus, this->ike_sa);
252
253 if (this->ike_sa->get_state(this->ike_sa) != IKE_REKEYING)
254 { /* in case of a collision we let the initiating task handle this */
255 establish_new(this);
256 /* make sure the IKE_SA is gone in case the peer fails to delete it */
257 lib->scheduler->schedule_job(lib->scheduler, (job_t*)
258 delete_ike_sa_job_create(this->ike_sa->get_id(this->ike_sa), TRUE),
259 90);
260 }
261 return SUCCESS;
262 }
263
264 /**
265 * Conclude any undetected rekey collision.
266 *
267 * If the peer does not detect the collision it will delete this IKE_SA.
268 * Depending on when our request reaches the peer and we receive the delete
269 * this may get called at different times.
270 *
271 * Returns TRUE if there was a collision, FALSE otherwise.
272 */
273 static bool conclude_undetected_collision(private_ike_rekey_t *this)
274 {
275 if (this->collision &&
276 this->collision->get_type(this->collision) == TASK_IKE_REKEY)
277 {
278 DBG1(DBG_IKE, "peer did not notice IKE_SA rekey collision, abort "
279 "active rekeying");
280 establish_new((private_ike_rekey_t*)this->collision);
281 return TRUE;
282 }
283 return FALSE;
284 }
285
286 METHOD(task_t, process_i, status_t,
287 private_ike_rekey_t *this, message_t *message)
288 {
289 if (message->get_notify(message, NO_ADDITIONAL_SAS))
290 {
291 DBG1(DBG_IKE, "peer seems to not support IKE rekeying, "
292 "starting reauthentication");
293 this->ike_sa->set_state(this->ike_sa, IKE_ESTABLISHED);
294 lib->processor->queue_job(lib->processor,
295 (job_t*)rekey_ike_sa_job_create(
296 this->ike_sa->get_id(this->ike_sa), TRUE));
297 return SUCCESS;
298 }
299
300 switch (this->ike_init->task.process(&this->ike_init->task, message))
301 {
302 case FAILED:
303 /* rekeying failed, fallback to old SA */
304 if (!conclude_undetected_collision(this))
305 {
306 schedule_delayed_rekey(this);
307 }
308 return SUCCESS;
309 case NEED_MORE:
310 /* bad dh group, try again */
311 this->ike_init->task.migrate(&this->ike_init->task, this->new_sa);
312 return NEED_MORE;
313 default:
314 break;
315 }
316
317 /* check for collisions */
318 if (this->collision &&
319 this->collision->get_type(this->collision) == TASK_IKE_REKEY)
320 {
321 private_ike_rekey_t *other = (private_ike_rekey_t*)this->collision;
322 host_t *host;
323 chunk_t this_nonce, other_nonce;
324
325 this_nonce = this->ike_init->get_lower_nonce(this->ike_init);
326 other_nonce = other->ike_init->get_lower_nonce(other->ike_init);
327
328 /* if we have the lower nonce, delete rekeyed SA. If not, delete
329 * the redundant. */
330 if (memcmp(this_nonce.ptr, other_nonce.ptr,
331 min(this_nonce.len, other_nonce.len)) < 0)
332 {
333 DBG1(DBG_IKE, "IKE_SA rekey collision lost, deleting redundant "
334 "IKE_SA %s[%d]", this->new_sa->get_name(this->new_sa),
335 this->new_sa->get_unique_id(this->new_sa));
336 /* apply host for a proper delete */
337 host = this->ike_sa->get_my_host(this->ike_sa);
338 this->new_sa->set_my_host(this->new_sa, host->clone(host));
339 host = this->ike_sa->get_other_host(this->ike_sa);
340 this->new_sa->set_other_host(this->new_sa, host->clone(host));
341 /* IKE_SAs in state IKE_REKEYED are silently deleted, so we use
342 * IKE_REKEYING */
343 this->new_sa->set_state(this->new_sa, IKE_REKEYING);
344 if (this->new_sa->delete(this->new_sa) == DESTROY_ME)
345 {
346 this->new_sa->destroy(this->new_sa);
347 }
348 else
349 {
350 charon->ike_sa_manager->checkin(charon->ike_sa_manager,
351 this->new_sa);
352 }
353 charon->bus->set_sa(charon->bus, this->ike_sa);
354 this->new_sa = NULL;
355 establish_new(other);
356 return SUCCESS;
357 }
358 /* peer should delete this SA. Add a timeout just in case. */
359 job_t *job = (job_t*)delete_ike_sa_job_create(
360 other->new_sa->get_id(other->new_sa), TRUE);
361 lib->scheduler->schedule_job(lib->scheduler, job,
362 HALF_OPEN_IKE_SA_TIMEOUT);
363 DBG1(DBG_IKE, "IKE_SA rekey collision won, waiting for delete for "
364 "redundant IKE_SA %s[%d]", other->new_sa->get_name(other->new_sa),
365 other->new_sa->get_unique_id(other->new_sa));
366 other->new_sa->set_state(other->new_sa, IKE_REKEYED);
367 charon->ike_sa_manager->checkin(charon->ike_sa_manager, other->new_sa);
368 other->new_sa = NULL;
369 charon->bus->set_sa(charon->bus, this->ike_sa);
370 }
371
372 establish_new(this);
373
374 /* rekeying successful, delete the IKE_SA using a subtask */
375 this->ike_delete = ike_delete_create(this->ike_sa, TRUE);
376 this->public.task.build = _build_i_delete;
377 this->public.task.process = _process_i_delete;
378
379 return NEED_MORE;
380 }
381
382 METHOD(task_t, get_type, task_type_t,
383 private_ike_rekey_t *this)
384 {
385 return TASK_IKE_REKEY;
386 }
387
388 METHOD(ike_rekey_t, did_collide, bool,
389 private_ike_rekey_t *this)
390 {
391 return this->collision &&
392 this->collision->get_type(this->collision) == TASK_IKE_REKEY;
393 }
394
395 METHOD(ike_rekey_t, collide, void,
396 private_ike_rekey_t* this, task_t *other)
397 {
398 DBG1(DBG_IKE, "detected %N collision with %N", task_type_names,
399 TASK_IKE_REKEY, task_type_names, other->get_type(other));
400
401 switch (other->get_type(other))
402 {
403 case TASK_IKE_DELETE:
404 conclude_undetected_collision(this);
405 other->destroy(other);
406 return;
407 case TASK_IKE_REKEY:
408 {
409 private_ike_rekey_t *rekey = (private_ike_rekey_t*)other;
410
411 if (!rekey->ike_init)
412 {
413 DBG1(DBG_IKE, "colliding exchange did not result in an IKE_SA, "
414 "ignore");
415 other->destroy(other);
416 return;
417 }
418 break;
419 }
420 default:
421 break;
422 }
423 DESTROY_IF(this->collision);
424 this->collision = other;
425 }
426
427 /**
428 * Cleanup the task
429 */
430 static void cleanup(private_ike_rekey_t *this)
431 {
432 ike_sa_t *cur_sa;
433
434 if (this->ike_init)
435 {
436 this->ike_init->task.destroy(&this->ike_init->task);
437 }
438 if (this->ike_delete)
439 {
440 this->ike_delete->task.destroy(&this->ike_delete->task);
441 }
442 cur_sa = charon->bus->get_sa(charon->bus);
443 DESTROY_IF(this->new_sa);
444 charon->bus->set_sa(charon->bus, cur_sa);
445 DESTROY_IF(this->collision);
446 }
447
448 METHOD(task_t, migrate, void,
449 private_ike_rekey_t *this, ike_sa_t *ike_sa)
450 {
451 cleanup(this);
452 this->collision = NULL;
453 this->ike_sa = ike_sa;
454 this->new_sa = NULL;
455 this->ike_init = NULL;
456 this->ike_delete = NULL;
457 }
458
459 METHOD(task_t, destroy, void,
460 private_ike_rekey_t *this)
461 {
462 cleanup(this);
463 free(this);
464 }
465
466 /*
467 * Described in header.
468 */
469 ike_rekey_t *ike_rekey_create(ike_sa_t *ike_sa, bool initiator)
470 {
471 private_ike_rekey_t *this;
472
473 INIT(this,
474 .public = {
475 .task = {
476 .get_type = _get_type,
477 .build = _build_r,
478 .process = _process_r,
479 .migrate = _migrate,
480 .destroy = _destroy,
481 },
482 .did_collide = _did_collide,
483 .collide = _collide,
484 },
485 .ike_sa = ike_sa,
486 .initiator = initiator,
487 );
488 if (initiator)
489 {
490 this->public.task.build = _build_i;
491 this->public.task.process = _process_i;
492 }
493
494 return &this->public;
495 }