2cfcdc1fc8bcbc886a56761da902e98e7b1185b8
[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(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 }