ikev2: Schedule a timeout for the delete message following passive IKE rekeying
[strongswan.git] / 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_post(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 ike_version_t version;
127
128 /* create new SA only on first try */
129 if (this->new_sa == NULL)
130 {
131 version = this->ike_sa->get_version(this->ike_sa);
132 this->new_sa = charon->ike_sa_manager->checkout_new(
133 charon->ike_sa_manager, version, TRUE);
134 if (!this->new_sa)
135 { /* shouldn't happen */
136 return FAILED;
137 }
138 this->new_sa->inherit_pre(this->new_sa, this->ike_sa);
139 this->ike_init = ike_init_create(this->new_sa, TRUE, this->ike_sa);
140 this->ike_sa->set_state(this->ike_sa, IKE_REKEYING);
141 }
142 this->ike_init->task.build(&this->ike_init->task, message);
143
144 return NEED_MORE;
145 }
146
147 METHOD(task_t, process_r, status_t,
148 private_ike_rekey_t *this, message_t *message)
149 {
150 enumerator_t *enumerator;
151 child_sa_t *child_sa;
152
153 if (this->ike_sa->get_state(this->ike_sa) == IKE_DELETING)
154 {
155 DBG1(DBG_IKE, "peer initiated rekeying, but we are deleting");
156 return NEED_MORE;
157 }
158
159 enumerator = this->ike_sa->create_child_sa_enumerator(this->ike_sa);
160 while (enumerator->enumerate(enumerator, (void**)&child_sa))
161 {
162 switch (child_sa->get_state(child_sa))
163 {
164 case CHILD_CREATED:
165 case CHILD_REKEYING:
166 case CHILD_RETRYING:
167 case CHILD_DELETING:
168 /* we do not allow rekeying while we have children in-progress */
169 DBG1(DBG_IKE, "peer initiated rekeying, but a child is half-open");
170 enumerator->destroy(enumerator);
171 return NEED_MORE;
172 default:
173 break;
174 }
175 }
176 enumerator->destroy(enumerator);
177
178 this->new_sa = charon->ike_sa_manager->checkout_new(charon->ike_sa_manager,
179 this->ike_sa->get_version(this->ike_sa), FALSE);
180 if (!this->new_sa)
181 { /* shouldn't happen */
182 return FAILED;
183 }
184 this->new_sa->inherit_pre(this->new_sa, this->ike_sa);
185 this->ike_init = ike_init_create(this->new_sa, FALSE, this->ike_sa);
186 this->ike_init->task.process(&this->ike_init->task, message);
187
188 return NEED_MORE;
189 }
190
191 METHOD(task_t, build_r, status_t,
192 private_ike_rekey_t *this, message_t *message)
193 {
194 if (this->new_sa == NULL)
195 {
196 /* IKE_SA/a CHILD_SA is in an inacceptable state, deny rekeying */
197 message->add_notify(message, TRUE, NO_PROPOSAL_CHOSEN, chunk_empty);
198 return SUCCESS;
199 }
200
201 if (this->ike_init->task.build(&this->ike_init->task, message) == FAILED)
202 {
203 return SUCCESS;
204 }
205
206 this->ike_sa->set_state(this->ike_sa, IKE_REKEYING);
207
208 /* rekeying successful, delete the IKE_SA using a subtask */
209 this->ike_delete = ike_delete_create(this->ike_sa, FALSE);
210 this->public.task.build = _build_r_delete;
211 this->public.task.process = _process_r_delete;
212
213 /* the peer does have to delete the IKE_SA. If it does not, we get a
214 * unusable IKE_SA in REKEYING state without a replacement. We consider
215 * this a timeout condition by the peer, and trigger a delete actively. */
216 lib->scheduler->schedule_job(lib->scheduler, (job_t*)
217 delete_ike_sa_job_create(this->ike_sa->get_id(this->ike_sa), TRUE), 90);
218
219 return NEED_MORE;
220 }
221
222 METHOD(task_t, process_i, status_t,
223 private_ike_rekey_t *this, message_t *message)
224 {
225 if (message->get_notify(message, NO_ADDITIONAL_SAS))
226 {
227 DBG1(DBG_IKE, "peer seems to not support IKE rekeying, "
228 "starting reauthentication");
229 this->ike_sa->set_state(this->ike_sa, IKE_ESTABLISHED);
230 lib->processor->queue_job(lib->processor,
231 (job_t*)rekey_ike_sa_job_create(
232 this->ike_sa->get_id(this->ike_sa), TRUE));
233 return SUCCESS;
234 }
235
236 switch (this->ike_init->task.process(&this->ike_init->task, message))
237 {
238 case FAILED:
239 /* rekeying failed, fallback to old SA */
240 if (!(this->collision && (
241 this->collision->get_type(this->collision) == TASK_IKE_DELETE ||
242 this->collision->get_type(this->collision) == TASK_IKE_REAUTH)))
243 {
244 job_t *job;
245 u_int32_t retry = RETRY_INTERVAL - (random() % RETRY_JITTER);
246 job = (job_t*)rekey_ike_sa_job_create(
247 this->ike_sa->get_id(this->ike_sa), FALSE);
248 DBG1(DBG_IKE, "IKE_SA rekeying failed, "
249 "trying again in %d seconds", retry);
250 this->ike_sa->set_state(this->ike_sa, IKE_ESTABLISHED);
251 lib->scheduler->schedule_job(lib->scheduler, job, retry);
252 }
253 return SUCCESS;
254 case NEED_MORE:
255 /* bad dh group, try again */
256 this->ike_init->task.migrate(&this->ike_init->task, this->new_sa);
257 return NEED_MORE;
258 default:
259 break;
260 }
261
262 /* check for collisions */
263 if (this->collision &&
264 this->collision->get_type(this->collision) == TASK_IKE_REKEY)
265 {
266 private_ike_rekey_t *other = (private_ike_rekey_t*)this->collision;
267
268 /* ike_init can be NULL, if child_sa is half-open */
269 if (other->ike_init)
270 {
271 host_t *host;
272 chunk_t this_nonce, other_nonce;
273
274 this_nonce = this->ike_init->get_lower_nonce(this->ike_init);
275 other_nonce = other->ike_init->get_lower_nonce(other->ike_init);
276
277 /* if we have the lower nonce, delete rekeyed SA. If not, delete
278 * the redundant. */
279 if (memcmp(this_nonce.ptr, other_nonce.ptr,
280 min(this_nonce.len, other_nonce.len)) > 0)
281 {
282 /* peer should delete this SA. Add a timeout just in case. */
283 job_t *job = (job_t*)delete_ike_sa_job_create(
284 other->new_sa->get_id(other->new_sa), TRUE);
285 lib->scheduler->schedule_job(lib->scheduler, job, 10);
286 DBG1(DBG_IKE, "IKE_SA rekey collision won, waiting for delete");
287 charon->ike_sa_manager->checkin(charon->ike_sa_manager, other->new_sa);
288 other->new_sa = NULL;
289 }
290 else
291 {
292 DBG1(DBG_IKE, "IKE_SA rekey collision lost, "
293 "deleting redundant IKE_SA");
294 /* apply host for a proper delete */
295 host = this->ike_sa->get_my_host(this->ike_sa);
296 this->new_sa->set_my_host(this->new_sa, host->clone(host));
297 host = this->ike_sa->get_other_host(this->ike_sa);
298 this->new_sa->set_other_host(this->new_sa, host->clone(host));
299 this->ike_sa->set_state(this->ike_sa, IKE_ESTABLISHED);
300 this->new_sa->set_state(this->new_sa, IKE_REKEYING);
301 if (this->new_sa->delete(this->new_sa) == DESTROY_ME)
302 {
303 this->new_sa->destroy(this->new_sa);
304 }
305 else
306 {
307 charon->ike_sa_manager->checkin(
308 charon->ike_sa_manager, this->new_sa);
309 /* set threads active IKE_SA after checkin */
310 charon->bus->set_sa(charon->bus, this->ike_sa);
311 }
312 this->new_sa = NULL;
313 establish_new(other);
314 return SUCCESS;
315 }
316 }
317 /* set threads active IKE_SA after checkin */
318 charon->bus->set_sa(charon->bus, this->ike_sa);
319 }
320
321 establish_new(this);
322
323 /* rekeying successful, delete the IKE_SA using a subtask */
324 this->ike_delete = ike_delete_create(this->ike_sa, TRUE);
325 this->public.task.build = _build_i_delete;
326 this->public.task.process = _process_i_delete;
327
328 return NEED_MORE;
329 }
330
331 METHOD(task_t, get_type, task_type_t,
332 private_ike_rekey_t *this)
333 {
334 return TASK_IKE_REKEY;
335 }
336
337 METHOD(ike_rekey_t, collide, void,
338 private_ike_rekey_t* this, task_t *other)
339 {
340 DBG1(DBG_IKE, "detected %N collision with %N", task_type_names,
341 TASK_IKE_REKEY, task_type_names, other->get_type(other));
342 DESTROY_IF(this->collision);
343 this->collision = other;
344 }
345
346 METHOD(task_t, migrate, void,
347 private_ike_rekey_t *this, ike_sa_t *ike_sa)
348 {
349 if (this->ike_init)
350 {
351 this->ike_init->task.destroy(&this->ike_init->task);
352 }
353 if (this->ike_delete)
354 {
355 this->ike_delete->task.destroy(&this->ike_delete->task);
356 }
357 DESTROY_IF(this->new_sa);
358 DESTROY_IF(this->collision);
359
360 this->collision = NULL;
361 this->ike_sa = ike_sa;
362 this->new_sa = NULL;
363 this->ike_init = NULL;
364 this->ike_delete = NULL;
365 }
366
367 METHOD(task_t, destroy, void,
368 private_ike_rekey_t *this)
369 {
370 if (this->ike_init)
371 {
372 this->ike_init->task.destroy(&this->ike_init->task);
373 }
374 if (this->ike_delete)
375 {
376 this->ike_delete->task.destroy(&this->ike_delete->task);
377 }
378 DESTROY_IF(this->new_sa);
379 DESTROY_IF(this->collision);
380 free(this);
381 }
382
383 /*
384 * Described in header.
385 */
386 ike_rekey_t *ike_rekey_create(ike_sa_t *ike_sa, bool initiator)
387 {
388 private_ike_rekey_t *this;
389
390 INIT(this,
391 .public = {
392 .task = {
393 .get_type = _get_type,
394 .build = _build_r,
395 .process = _process_r,
396 .migrate = _migrate,
397 .destroy = _destroy,
398 },
399 .collide = _collide,
400 },
401 .ike_sa = ike_sa,
402 .initiator = initiator,
403 );
404 if (initiator)
405 {
406 this->public.task.build = _build_i;
407 this->public.task.process = _process_i;
408 }
409
410 return &this->public;
411 }