175ffcf08b2e2663b4386a47e1065670ce78f997
[strongswan.git] / src / charon / sa / tasks / ike_rekey.c
1 /*
2 * Copyright (C) 2005-2007 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 * $Id$
17 */
18
19 #include "ike_rekey.h"
20
21 #include <daemon.h>
22 #include <encoding/payloads/notify_payload.h>
23 #include <sa/tasks/ike_init.h>
24 #include <processing/jobs/delete_ike_sa_job.h>
25 #include <processing/jobs/rekey_ike_sa_job.h>
26
27
28 typedef struct private_ike_rekey_t private_ike_rekey_t;
29
30 /**
31 * Private members of a ike_rekey_t task.
32 */
33 struct private_ike_rekey_t {
34
35 /**
36 * Public methods and task_t interface.
37 */
38 ike_rekey_t public;
39
40 /**
41 * Assigned IKE_SA.
42 */
43 ike_sa_t *ike_sa;
44
45 /**
46 * New IKE_SA which replaces the current one
47 */
48 ike_sa_t *new_sa;
49
50 /**
51 * Are we the initiator?
52 */
53 bool initiator;
54
55 /**
56 * the IKE_INIT task which is reused to simplify rekeying
57 */
58 ike_init_t *ike_init;
59
60 /**
61 * colliding task detected by the task manager
62 */
63 task_t *collision;
64 };
65
66 /**
67 * Implementation of task_t.build for initiator
68 */
69 static status_t build_i(private_ike_rekey_t *this, message_t *message)
70 {
71 peer_cfg_t *peer_cfg;
72 host_t *other_host;
73
74 /* create new SA only on first try */
75 if (this->new_sa == NULL)
76 {
77 this->new_sa = charon->ike_sa_manager->checkout_new(charon->ike_sa_manager,
78 TRUE);
79
80 peer_cfg = this->ike_sa->get_peer_cfg(this->ike_sa);
81 other_host = this->ike_sa->get_other_host(this->ike_sa);
82 this->new_sa->set_peer_cfg(this->new_sa, peer_cfg);
83 this->new_sa->set_other_host(this->new_sa, other_host->clone(other_host));
84 this->ike_init = ike_init_create(this->new_sa, TRUE, this->ike_sa);
85 this->ike_sa->set_state(this->ike_sa, IKE_REKEYING);
86 }
87 this->ike_init->task.build(&this->ike_init->task, message);
88
89 return NEED_MORE;
90 }
91
92 /**
93 * Implementation of task_t.process for initiator
94 */
95 static status_t process_r(private_ike_rekey_t *this, message_t *message)
96 {
97 peer_cfg_t *peer_cfg;
98 iterator_t *iterator;
99 child_sa_t *child_sa;
100
101 if (this->ike_sa->get_state(this->ike_sa) == IKE_DELETING)
102 {
103 DBG1(DBG_IKE, "peer initiated rekeying, but we are deleting");
104 return NEED_MORE;
105 }
106
107 iterator = this->ike_sa->create_child_sa_iterator(this->ike_sa);
108 while (iterator->iterate(iterator, (void**)&child_sa))
109 {
110 switch (child_sa->get_state(child_sa))
111 {
112 case CHILD_CREATED:
113 case CHILD_REKEYING:
114 case CHILD_DELETING:
115 /* we do not allow rekeying while we have children in-progress */
116 DBG1(DBG_IKE, "peer initiated rekeying, but a child is half-open");
117 iterator->destroy(iterator);
118 return NEED_MORE;
119 default:
120 break;
121 }
122 }
123 iterator->destroy(iterator);
124
125 this->new_sa = charon->ike_sa_manager->checkout_new(charon->ike_sa_manager,
126 FALSE);
127
128 peer_cfg = this->ike_sa->get_peer_cfg(this->ike_sa);
129 this->new_sa->set_peer_cfg(this->new_sa, peer_cfg);
130 this->ike_init = ike_init_create(this->new_sa, FALSE, this->ike_sa);
131 this->ike_init->task.process(&this->ike_init->task, message);
132
133 return NEED_MORE;
134 }
135
136 /**
137 * Implementation of task_t.build for responder
138 */
139 static status_t build_r(private_ike_rekey_t *this, message_t *message)
140 {
141 if (this->new_sa == NULL)
142 {
143 /* IKE_SA/a CHILD_SA is in an inacceptable state, deny rekeying */
144 message->add_notify(message, TRUE, NO_PROPOSAL_CHOSEN, chunk_empty);
145 return SUCCESS;
146 }
147
148 if (this->ike_init->task.build(&this->ike_init->task, message) == FAILED)
149 {
150 return SUCCESS;
151 }
152
153 this->ike_sa->set_state(this->ike_sa, IKE_REKEYING);
154 this->new_sa->set_state(this->new_sa, IKE_ESTABLISHED);
155
156 return SUCCESS;
157 }
158
159 /**
160 * Implementation of task_t.process for initiator
161 */
162 static status_t process_i(private_ike_rekey_t *this, message_t *message)
163 {
164 job_t *job;
165 ike_sa_id_t *to_delete;
166
167 switch (this->ike_init->task.process(&this->ike_init->task, message))
168 {
169 case FAILED:
170 /* rekeying failed, fallback to old SA */
171 if (!(this->collision && (
172 this->collision->get_type(this->collision) == IKE_DELETE ||
173 this->collision->get_type(this->collision) == IKE_REAUTH)))
174 {
175 job_t *job;
176 u_int32_t retry = RETRY_INTERVAL - (random() % RETRY_JITTER);
177 job = (job_t*)rekey_ike_sa_job_create(
178 this->ike_sa->get_id(this->ike_sa), FALSE);
179 DBG1(DBG_IKE, "IKE_SA rekeying failed, "
180 "trying again in %d seconds", retry);
181 this->ike_sa->set_state(this->ike_sa, IKE_ESTABLISHED);
182 charon->scheduler->schedule_job(charon->scheduler, job, retry * 1000);
183 }
184 return SUCCESS;
185 case NEED_MORE:
186 /* bad dh group, try again */
187 this->ike_init->task.migrate(&this->ike_init->task, this->new_sa);
188 return NEED_MORE;
189 default:
190 break;
191 }
192
193 this->new_sa->set_state(this->new_sa, IKE_ESTABLISHED);
194 to_delete = this->ike_sa->get_id(this->ike_sa);
195
196 /* check for collisions */
197 if (this->collision &&
198 this->collision->get_type(this->collision) == IKE_REKEY)
199 {
200 chunk_t this_nonce, other_nonce;
201 host_t *host;
202 private_ike_rekey_t *other = (private_ike_rekey_t*)this->collision;
203
204 this_nonce = this->ike_init->get_lower_nonce(this->ike_init);
205 other_nonce = other->ike_init->get_lower_nonce(other->ike_init);
206
207 /* if we have the lower nonce, delete rekeyed SA. If not, delete
208 * the redundant. */
209 if (memcmp(this_nonce.ptr, other_nonce.ptr,
210 min(this_nonce.len, other_nonce.len)) < 0)
211 {
212 DBG1(DBG_IKE, "IKE_SA rekey collision won, deleting rekeyed IKE_SA");
213 charon->ike_sa_manager->checkin(charon->ike_sa_manager, other->new_sa);
214 }
215 else
216 {
217 DBG1(DBG_IKE, "IKE_SA rekey collision lost, deleting redundant IKE_SA");
218 /* apply host for a proper delete */
219 host = this->ike_sa->get_my_host(this->ike_sa);
220 this->new_sa->set_my_host(this->new_sa, host->clone(host));
221 host = this->ike_sa->get_other_host(this->ike_sa);
222 this->new_sa->set_other_host(this->new_sa, host->clone(host));
223 this->ike_sa->set_state(this->ike_sa, IKE_ESTABLISHED);
224 to_delete = this->new_sa->get_id(this->new_sa);
225 charon->ike_sa_manager->checkin(charon->ike_sa_manager, this->new_sa);
226 /* inherit to other->new_sa in destroy() */
227 this->new_sa = other->new_sa;
228 other->new_sa = NULL;
229 }
230 }
231
232 job = (job_t*)delete_ike_sa_job_create(to_delete, TRUE);
233 charon->processor->queue_job(charon->processor, job);
234
235 return SUCCESS;
236 }
237
238 /**
239 * Implementation of task_t.get_type
240 */
241 static task_type_t get_type(private_ike_rekey_t *this)
242 {
243 return IKE_REKEY;
244 }
245
246 static void collide(private_ike_rekey_t* this, task_t *other)
247 {
248 DESTROY_IF(this->collision);
249 this->collision = other;
250 }
251
252 /**
253 * Implementation of task_t.migrate
254 */
255 static void migrate(private_ike_rekey_t *this, ike_sa_t *ike_sa)
256 {
257 if (this->ike_init)
258 {
259 this->ike_init->task.destroy(&this->ike_init->task);
260 }
261 if (this->new_sa)
262 {
263 charon->ike_sa_manager->checkin_and_destroy(charon->ike_sa_manager,
264 this->new_sa);
265 }
266 DESTROY_IF(this->collision);
267
268 this->collision = NULL;
269 this->ike_sa = ike_sa;
270 this->new_sa = NULL;
271 this->ike_init = NULL;
272 }
273
274 /**
275 * Implementation of task_t.destroy
276 */
277 static void destroy(private_ike_rekey_t *this)
278 {
279 if (this->new_sa)
280 {
281 if (this->new_sa->get_state(this->new_sa) == IKE_ESTABLISHED &&
282 this->new_sa->inherit(this->new_sa, this->ike_sa) != DESTROY_ME)
283 {
284 charon->ike_sa_manager->checkin(charon->ike_sa_manager, this->new_sa);
285 }
286 else
287 {
288 charon->ike_sa_manager->checkin_and_destroy(charon->ike_sa_manager,
289 this->new_sa);
290 }
291 }
292 if (this->ike_init)
293 {
294 this->ike_init->task.destroy(&this->ike_init->task);
295 }
296 DESTROY_IF(this->collision);
297 free(this);
298 }
299
300 /*
301 * Described in header.
302 */
303 ike_rekey_t *ike_rekey_create(ike_sa_t *ike_sa, bool initiator)
304 {
305 private_ike_rekey_t *this = malloc_thing(private_ike_rekey_t);
306
307 this->public.collide = (void(*)(ike_rekey_t*,task_t*))collide;
308 this->public.task.get_type = (task_type_t(*)(task_t*))get_type;
309 this->public.task.migrate = (void(*)(task_t*,ike_sa_t*))migrate;
310 this->public.task.destroy = (void(*)(task_t*))destroy;
311 if (initiator)
312 {
313 this->public.task.build = (status_t(*)(task_t*,message_t*))build_i;
314 this->public.task.process = (status_t(*)(task_t*,message_t*))process_i;
315 }
316 else
317 {
318 this->public.task.build = (status_t(*)(task_t*,message_t*))build_r;
319 this->public.task.process = (status_t(*)(task_t*,message_t*))process_r;
320 }
321
322 this->ike_sa = ike_sa;
323 this->new_sa = NULL;
324 this->ike_init = NULL;
325 this->initiator = initiator;
326 this->collision = NULL;
327
328 return &this->public;
329 }