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[strongswan.git] / src / libcharon / sa / ikev2 / tasks / ike_init.c
1 /*
2 * Copyright (C) 2008-2019 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_init.h"
19
20 #include <string.h>
21
22 #include <daemon.h>
23 #include <bio/bio_reader.h>
24 #include <bio/bio_writer.h>
25 #include <sa/ikev2/keymat_v2.h>
26 #include <crypto/diffie_hellman.h>
27 #include <crypto/hashers/hash_algorithm_set.h>
28 #include <encoding/payloads/sa_payload.h>
29 #include <encoding/payloads/ke_payload.h>
30 #include <encoding/payloads/nonce_payload.h>
31
32 /** maximum retries to do with cookies/other dh groups */
33 #define MAX_RETRIES 5
34
35 typedef struct private_ike_init_t private_ike_init_t;
36
37 /**
38 * Private members of a ike_init_t task.
39 */
40 struct private_ike_init_t {
41
42 /**
43 * Public methods and task_t interface.
44 */
45 ike_init_t public;
46
47 /**
48 * Assigned IKE_SA.
49 */
50 ike_sa_t *ike_sa;
51
52 /**
53 * Are we the initiator?
54 */
55 bool initiator;
56
57 /**
58 * diffie hellman group to use
59 */
60 diffie_hellman_group_t dh_group;
61
62 /**
63 * diffie hellman key exchange
64 */
65 diffie_hellman_t *dh;
66
67 /**
68 * Applying DH public value failed?
69 */
70 bool dh_failed;
71
72 /**
73 * Keymat derivation (from IKE_SA)
74 */
75 keymat_v2_t *keymat;
76
77 /**
78 * nonce chosen by us
79 */
80 chunk_t my_nonce;
81
82 /**
83 * nonce chosen by peer
84 */
85 chunk_t other_nonce;
86
87 /**
88 * nonce generator
89 */
90 nonce_gen_t *nonceg;
91
92 /**
93 * Negotiated proposal used for IKE_SA
94 */
95 proposal_t *proposal;
96
97 /**
98 * Old IKE_SA which gets rekeyed
99 */
100 ike_sa_t *old_sa;
101
102 /**
103 * cookie received from responder
104 */
105 chunk_t cookie;
106
107 /**
108 * retries done so far after failure (cookie or bad dh group)
109 */
110 u_int retry;
111
112 /**
113 * Whether to use Signature Authentication as per RFC 7427
114 */
115 bool signature_authentication;
116
117 /**
118 * Whether to follow IKEv2 redirects as per RFC 5685
119 */
120 bool follow_redirects;
121 };
122
123 /**
124 * Allocate our own nonce value
125 */
126 static bool generate_nonce(private_ike_init_t *this)
127 {
128 if (!this->nonceg)
129 {
130 DBG1(DBG_IKE, "no nonce generator found to create nonce");
131 return FALSE;
132 }
133 if (!this->nonceg->allocate_nonce(this->nonceg, NONCE_SIZE,
134 &this->my_nonce))
135 {
136 DBG1(DBG_IKE, "nonce allocation failed");
137 return FALSE;
138 }
139 return TRUE;
140 }
141
142 /**
143 * Notify the peer about the hash algorithms we support or expect,
144 * as per RFC 7427
145 */
146 static void send_supported_hash_algorithms(private_ike_init_t *this,
147 message_t *message)
148 {
149 hash_algorithm_set_t *algos;
150 enumerator_t *enumerator, *rounds;
151 bio_writer_t *writer;
152 hash_algorithm_t hash;
153 peer_cfg_t *peer;
154 auth_cfg_t *auth;
155 auth_rule_t rule;
156 signature_params_t *config;
157 int written;
158 size_t len = BUF_LEN;
159 char buf[len];
160 char *pos = buf;
161 char *plugin_name;
162
163 algos = hash_algorithm_set_create();
164 peer = this->ike_sa->get_peer_cfg(this->ike_sa);
165 if (peer)
166 {
167 rounds = peer->create_auth_cfg_enumerator(peer, FALSE);
168 while (rounds->enumerate(rounds, &auth))
169 {
170 enumerator = auth->create_enumerator(auth);
171 while (enumerator->enumerate(enumerator, &rule, &config))
172 {
173 if (rule == AUTH_RULE_IKE_SIGNATURE_SCHEME)
174 {
175 hash = hasher_from_signature_scheme(config->scheme,
176 config->params);
177 if (hasher_algorithm_for_ikev2(hash))
178 {
179 algos->add(algos, hash);
180 }
181 }
182 }
183 enumerator->destroy(enumerator);
184 }
185 rounds->destroy(rounds);
186 }
187
188 if (!algos->count(algos))
189 {
190 enumerator = lib->crypto->create_hasher_enumerator(lib->crypto);
191 while (enumerator->enumerate(enumerator, &hash, &plugin_name))
192 {
193 if (hasher_algorithm_for_ikev2(hash))
194 {
195 algos->add(algos, hash);
196 }
197 }
198 enumerator->destroy(enumerator);
199 }
200
201 if (algos->count(algos))
202 {
203 writer = bio_writer_create(0);
204 enumerator = algos->create_enumerator(algos);
205 while (enumerator->enumerate(enumerator, &hash))
206 {
207 writer->write_uint16(writer, hash);
208
209 /* generate debug output */
210 written = snprintf(pos, len, " %N", hash_algorithm_short_names,
211 hash);
212 if (written > 0 && written < len)
213 {
214 pos += written;
215 len -= written;
216 }
217 }
218 enumerator->destroy(enumerator);
219 message->add_notify(message, FALSE, SIGNATURE_HASH_ALGORITHMS,
220 writer->get_buf(writer));
221 writer->destroy(writer);
222
223 *pos = '\0';
224 DBG2(DBG_CFG, "sending supported signature hash algorithms:%s", buf);
225 }
226 algos->destroy(algos);
227 }
228
229 /**
230 * Store algorithms supported by other peer
231 */
232 static void handle_supported_hash_algorithms(private_ike_init_t *this,
233 notify_payload_t *notify)
234 {
235 bio_reader_t *reader;
236 uint16_t algo;
237 int written;
238 size_t len = BUF_LEN;
239 char buf[len];
240 char *pos = buf;
241 bool added = FALSE;
242
243 reader = bio_reader_create(notify->get_notification_data(notify));
244 while (reader->remaining(reader) >= 2 && reader->read_uint16(reader, &algo))
245 {
246 if (hasher_algorithm_for_ikev2(algo))
247 {
248 this->keymat->add_hash_algorithm(this->keymat, algo);
249 added = TRUE;
250
251 /* generate debug output */
252 written = snprintf(pos, len, " %N", hash_algorithm_short_names,
253 algo);
254 if (written > 0 && written < len)
255 {
256 pos += written;
257 len -= written;
258 }
259 }
260 }
261 reader->destroy(reader);
262
263 *pos = '\0';
264 DBG2(DBG_CFG, "received supported signature hash algorithms:%s", buf);
265
266 if (added)
267 {
268 this->ike_sa->enable_extension(this->ike_sa, EXT_SIGNATURE_AUTH);
269 }
270 }
271
272 /**
273 * Check whether to send a USE_PPK notify
274 */
275 static bool send_use_ppk(private_ike_init_t *this)
276 {
277 peer_cfg_t *peer;
278 enumerator_t *keys;
279 shared_key_t *key;
280 bool use_ppk = FALSE;
281
282 if (this->initiator)
283 {
284 peer = this->ike_sa->get_peer_cfg(this->ike_sa);
285 if (peer->get_ppk_id(peer))
286 {
287 use_ppk = TRUE;
288 }
289 }
290 else if (this->ike_sa->supports_extension(this->ike_sa, EXT_PPK))
291 {
292 /* check if we have at least one PPK available */
293 keys = lib->credmgr->create_shared_enumerator(lib->credmgr, SHARED_PPK,
294 NULL, NULL);
295 if (keys->enumerate(keys, &key, NULL, NULL))
296 {
297 use_ppk = TRUE;
298 }
299 keys->destroy(keys);
300 }
301 return use_ppk;
302 }
303
304 /**
305 * build the payloads for the message
306 */
307 static bool build_payloads(private_ike_init_t *this, message_t *message)
308 {
309 sa_payload_t *sa_payload;
310 ke_payload_t *ke_payload;
311 nonce_payload_t *nonce_payload;
312 linked_list_t *proposal_list, *other_dh_groups;
313 ike_sa_id_t *id;
314 proposal_t *proposal;
315 enumerator_t *enumerator;
316 ike_cfg_t *ike_cfg;
317
318 id = this->ike_sa->get_id(this->ike_sa);
319
320 ike_cfg = this->ike_sa->get_ike_cfg(this->ike_sa);
321
322 if (this->initiator)
323 {
324 proposal_list = ike_cfg->get_proposals(ike_cfg);
325 other_dh_groups = linked_list_create();
326 enumerator = proposal_list->create_enumerator(proposal_list);
327 while (enumerator->enumerate(enumerator, (void**)&proposal))
328 {
329 /* include SPI of new IKE_SA when we are rekeying */
330 if (this->old_sa)
331 {
332 proposal->set_spi(proposal, id->get_initiator_spi(id));
333 }
334 /* move the selected DH group to the front of the proposal */
335 if (!proposal->promote_dh_group(proposal, this->dh_group))
336 { /* the proposal does not include the group, move to the back */
337 proposal_list->remove_at(proposal_list, enumerator);
338 other_dh_groups->insert_last(other_dh_groups, proposal);
339 }
340 }
341 enumerator->destroy(enumerator);
342 /* add proposals that don't contain the selected group */
343 enumerator = other_dh_groups->create_enumerator(other_dh_groups);
344 while (enumerator->enumerate(enumerator, (void**)&proposal))
345 { /* no need to remove from the list as we destroy it anyway*/
346 proposal_list->insert_last(proposal_list, proposal);
347 }
348 enumerator->destroy(enumerator);
349 other_dh_groups->destroy(other_dh_groups);
350
351 sa_payload = sa_payload_create_from_proposals_v2(proposal_list);
352 proposal_list->destroy_offset(proposal_list, offsetof(proposal_t, destroy));
353 }
354 else
355 {
356 if (this->old_sa)
357 {
358 /* include SPI of new IKE_SA when we are rekeying */
359 this->proposal->set_spi(this->proposal, id->get_responder_spi(id));
360 }
361 sa_payload = sa_payload_create_from_proposal_v2(this->proposal);
362 }
363 message->add_payload(message, (payload_t*)sa_payload);
364
365 ke_payload = ke_payload_create_from_diffie_hellman(PLV2_KEY_EXCHANGE,
366 this->dh);
367 if (!ke_payload)
368 {
369 DBG1(DBG_IKE, "creating KE payload failed");
370 return FALSE;
371 }
372 nonce_payload = nonce_payload_create(PLV2_NONCE);
373 nonce_payload->set_nonce(nonce_payload, this->my_nonce);
374
375 if (this->old_sa)
376 { /* payload order differs if we are rekeying */
377 message->add_payload(message, (payload_t*)nonce_payload);
378 message->add_payload(message, (payload_t*)ke_payload);
379 }
380 else
381 {
382 message->add_payload(message, (payload_t*)ke_payload);
383 message->add_payload(message, (payload_t*)nonce_payload);
384 }
385
386 /* negotiate fragmentation if we are not rekeying */
387 if (!this->old_sa &&
388 ike_cfg->fragmentation(ike_cfg) != FRAGMENTATION_NO)
389 {
390 if (this->initiator ||
391 this->ike_sa->supports_extension(this->ike_sa,
392 EXT_IKE_FRAGMENTATION))
393 {
394 message->add_notify(message, FALSE, FRAGMENTATION_SUPPORTED,
395 chunk_empty);
396 }
397 }
398 /* submit supported hash algorithms for signature authentication */
399 if (!this->old_sa && this->signature_authentication)
400 {
401 if (this->initiator ||
402 this->ike_sa->supports_extension(this->ike_sa,
403 EXT_SIGNATURE_AUTH))
404 {
405 send_supported_hash_algorithms(this, message);
406 }
407 }
408 /* notify other peer if we support redirection */
409 if (!this->old_sa && this->initiator && this->follow_redirects)
410 {
411 identification_t *gateway;
412 host_t *from;
413 chunk_t data;
414
415 from = this->ike_sa->get_redirected_from(this->ike_sa);
416 if (from)
417 {
418 gateway = identification_create_from_sockaddr(
419 from->get_sockaddr(from));
420 data = redirect_data_create(gateway, chunk_empty);
421 message->add_notify(message, FALSE, REDIRECTED_FROM, data);
422 chunk_free(&data);
423 gateway->destroy(gateway);
424 }
425 else
426 {
427 message->add_notify(message, FALSE, REDIRECT_SUPPORTED,
428 chunk_empty);
429 }
430 }
431 /* notify the peer if we want to use/support PPK */
432 if (!this->old_sa && send_use_ppk(this))
433 {
434 message->add_notify(message, FALSE, USE_PPK, chunk_empty);
435 }
436 /* notify the peer if we accept childless IKE_SAs */
437 if (!this->old_sa && !this->initiator &&
438 ike_cfg->childless(ike_cfg) != CHILDLESS_NEVER)
439 {
440 message->add_notify(message, FALSE, CHILDLESS_IKEV2_SUPPORTED,
441 chunk_empty);
442 }
443 return TRUE;
444 }
445
446 /**
447 * Process the SA payload and select a proposal
448 */
449 static void process_sa_payload(private_ike_init_t *this, message_t *message,
450 sa_payload_t *sa_payload)
451 {
452 ike_cfg_t *ike_cfg, *cfg, *alt_cfg = NULL;
453 enumerator_t *enumerator;
454 linked_list_t *proposal_list;
455 host_t *me, *other;
456 proposal_selection_flag_t flags = 0;
457
458 ike_cfg = this->ike_sa->get_ike_cfg(this->ike_sa);
459
460 proposal_list = sa_payload->get_proposals(sa_payload);
461 if (this->ike_sa->supports_extension(this->ike_sa, EXT_STRONGSWAN))
462 {
463 flags |= PROPOSAL_ALLOW_PRIVATE;
464 }
465 if (!lib->settings->get_bool(lib->settings,
466 "%s.prefer_configured_proposals", TRUE, lib->ns))
467 {
468 flags |= PROPOSAL_PREFER_SUPPLIED;
469 }
470 this->proposal = ike_cfg->select_proposal(ike_cfg, proposal_list, flags);
471 if (!this->proposal)
472 {
473 if (!this->initiator && !this->old_sa)
474 {
475 me = message->get_destination(message);
476 other = message->get_source(message);
477 enumerator = charon->backends->create_ike_cfg_enumerator(
478 charon->backends, me, other, IKEV2);
479 while (enumerator->enumerate(enumerator, &cfg))
480 {
481 if (ike_cfg == cfg)
482 { /* already tried and failed */
483 continue;
484 }
485 DBG1(DBG_IKE, "no matching proposal found, trying alternative "
486 "config");
487 this->proposal = cfg->select_proposal(cfg, proposal_list,
488 flags);
489 if (this->proposal)
490 {
491 alt_cfg = cfg->get_ref(cfg);
492 break;
493 }
494 }
495 enumerator->destroy(enumerator);
496 }
497 if (alt_cfg)
498 {
499 this->ike_sa->set_ike_cfg(this->ike_sa, alt_cfg);
500 alt_cfg->destroy(alt_cfg);
501 }
502 else
503 {
504 charon->bus->alert(charon->bus, ALERT_PROPOSAL_MISMATCH_IKE,
505 proposal_list);
506 }
507 }
508 proposal_list->destroy_offset(proposal_list,
509 offsetof(proposal_t, destroy));
510 }
511
512 /**
513 * Read payloads from message
514 */
515 static void process_payloads(private_ike_init_t *this, message_t *message)
516 {
517 enumerator_t *enumerator;
518 payload_t *payload;
519 ke_payload_t *ke_payload = NULL;
520
521 enumerator = message->create_payload_enumerator(message);
522 while (enumerator->enumerate(enumerator, &payload))
523 {
524 switch (payload->get_type(payload))
525 {
526 case PLV2_SECURITY_ASSOCIATION:
527 {
528 process_sa_payload(this, message, (sa_payload_t*)payload);
529 break;
530 }
531 case PLV2_KEY_EXCHANGE:
532 {
533 ke_payload = (ke_payload_t*)payload;
534
535 this->dh_group = ke_payload->get_dh_group_number(ke_payload);
536 break;
537 }
538 case PLV2_NONCE:
539 {
540 nonce_payload_t *nonce_payload = (nonce_payload_t*)payload;
541
542 this->other_nonce = nonce_payload->get_nonce(nonce_payload);
543 break;
544 }
545 case PLV2_NOTIFY:
546 {
547 notify_payload_t *notify = (notify_payload_t*)payload;
548
549 switch (notify->get_notify_type(notify))
550 {
551 case FRAGMENTATION_SUPPORTED:
552 this->ike_sa->enable_extension(this->ike_sa,
553 EXT_IKE_FRAGMENTATION);
554 break;
555 case SIGNATURE_HASH_ALGORITHMS:
556 if (this->signature_authentication)
557 {
558 handle_supported_hash_algorithms(this, notify);
559 }
560 break;
561 case USE_PPK:
562 if (!this->old_sa)
563 {
564 this->ike_sa->enable_extension(this->ike_sa,
565 EXT_PPK);
566 }
567 break;
568 case REDIRECTED_FROM:
569 {
570 identification_t *gateway;
571 chunk_t data;
572
573 data = notify->get_notification_data(notify);
574 gateway = redirect_data_parse(data, NULL);
575 if (!gateway)
576 {
577 DBG1(DBG_IKE, "received invalid REDIRECTED_FROM "
578 "notify, ignored");
579 break;
580 }
581 DBG1(DBG_IKE, "client got redirected from %Y", gateway);
582 gateway->destroy(gateway);
583 /* fall-through */
584 }
585 case REDIRECT_SUPPORTED:
586 if (!this->old_sa)
587 {
588 this->ike_sa->enable_extension(this->ike_sa,
589 EXT_IKE_REDIRECTION);
590 }
591 break;
592 case CHILDLESS_IKEV2_SUPPORTED:
593 if (this->initiator && !this->old_sa)
594 {
595 this->ike_sa->enable_extension(this->ike_sa,
596 EXT_IKE_CHILDLESS);
597 }
598 break;
599 default:
600 /* other notifies are handled elsewhere */
601 break;
602 }
603
604 }
605 default:
606 break;
607 }
608 }
609 enumerator->destroy(enumerator);
610
611 if (this->proposal)
612 {
613 this->ike_sa->set_proposal(this->ike_sa, this->proposal);
614 }
615
616 if (ke_payload && this->proposal &&
617 this->proposal->has_dh_group(this->proposal, this->dh_group))
618 {
619 if (!this->initiator)
620 {
621 this->dh = this->keymat->keymat.create_dh(
622 &this->keymat->keymat, this->dh_group);
623 }
624 else if (this->dh)
625 {
626 this->dh_failed = this->dh->get_dh_group(this->dh) != this->dh_group;
627 }
628 if (this->dh && !this->dh_failed)
629 {
630 this->dh_failed = !this->dh->set_other_public_value(this->dh,
631 ke_payload->get_key_exchange_data(ke_payload));
632 }
633 }
634 }
635
636 METHOD(task_t, build_i, status_t,
637 private_ike_init_t *this, message_t *message)
638 {
639 ike_cfg_t *ike_cfg;
640
641 ike_cfg = this->ike_sa->get_ike_cfg(this->ike_sa);
642
643 DBG0(DBG_IKE, "initiating IKE_SA %s[%d] to %H",
644 this->ike_sa->get_name(this->ike_sa),
645 this->ike_sa->get_unique_id(this->ike_sa),
646 this->ike_sa->get_other_host(this->ike_sa));
647 this->ike_sa->set_state(this->ike_sa, IKE_CONNECTING);
648
649 if (this->retry >= MAX_RETRIES)
650 {
651 DBG1(DBG_IKE, "giving up after %d retries", MAX_RETRIES);
652 return FAILED;
653 }
654
655 /* if we are retrying after an INVALID_KE_PAYLOAD we already have one */
656 if (!this->dh)
657 {
658 if (this->old_sa && lib->settings->get_bool(lib->settings,
659 "%s.prefer_previous_dh_group", TRUE, lib->ns))
660 { /* reuse the DH group we used for the old IKE_SA when rekeying */
661 proposal_t *proposal;
662 uint16_t dh_group;
663
664 proposal = this->old_sa->get_proposal(this->old_sa);
665 if (proposal->get_algorithm(proposal, DIFFIE_HELLMAN_GROUP,
666 &dh_group, NULL))
667 {
668 this->dh_group = dh_group;
669 }
670 else
671 { /* this shouldn't happen, but let's be safe */
672 this->dh_group = ike_cfg->get_dh_group(ike_cfg);
673 }
674 }
675 else
676 {
677 this->dh_group = ike_cfg->get_dh_group(ike_cfg);
678 }
679 this->dh = this->keymat->keymat.create_dh(&this->keymat->keymat,
680 this->dh_group);
681 if (!this->dh)
682 {
683 DBG1(DBG_IKE, "configured DH group %N not supported",
684 diffie_hellman_group_names, this->dh_group);
685 return FAILED;
686 }
687 }
688 else if (this->dh->get_dh_group(this->dh) != this->dh_group)
689 { /* reset DH instance if group changed (INVALID_KE_PAYLOAD) */
690 this->dh->destroy(this->dh);
691 this->dh = this->keymat->keymat.create_dh(&this->keymat->keymat,
692 this->dh_group);
693 if (!this->dh)
694 {
695 DBG1(DBG_IKE, "requested DH group %N not supported",
696 diffie_hellman_group_names, this->dh_group);
697 return FAILED;
698 }
699 }
700
701 /* generate nonce only when we are trying the first time */
702 if (this->my_nonce.ptr == NULL)
703 {
704 if (!generate_nonce(this))
705 {
706 return FAILED;
707 }
708 }
709
710 if (this->cookie.ptr)
711 {
712 message->add_notify(message, FALSE, COOKIE, this->cookie);
713 }
714
715 if (!build_payloads(this, message))
716 {
717 return FAILED;
718 }
719
720 #ifdef ME
721 {
722 chunk_t connect_id = this->ike_sa->get_connect_id(this->ike_sa);
723 if (connect_id.ptr)
724 {
725 message->add_notify(message, FALSE, ME_CONNECTID, connect_id);
726 }
727 }
728 #endif /* ME */
729
730 return NEED_MORE;
731 }
732
733 METHOD(task_t, process_r, status_t,
734 private_ike_init_t *this, message_t *message)
735 {
736 DBG0(DBG_IKE, "%H is initiating an IKE_SA", message->get_source(message));
737 this->ike_sa->set_state(this->ike_sa, IKE_CONNECTING);
738
739 if (!generate_nonce(this))
740 {
741 return FAILED;
742 }
743
744 #ifdef ME
745 {
746 notify_payload_t *notify = message->get_notify(message, ME_CONNECTID);
747 if (notify)
748 {
749 chunk_t connect_id = notify->get_notification_data(notify);
750 DBG2(DBG_IKE, "received ME_CONNECTID %#B", &connect_id);
751 charon->connect_manager->stop_checks(charon->connect_manager,
752 connect_id);
753 }
754 }
755 #endif /* ME */
756
757 process_payloads(this, message);
758
759 return NEED_MORE;
760 }
761
762 /**
763 * Derive the keymat for the IKE_SA
764 */
765 static bool derive_keys(private_ike_init_t *this,
766 chunk_t nonce_i, chunk_t nonce_r)
767 {
768 keymat_v2_t *old_keymat;
769 pseudo_random_function_t prf_alg = PRF_UNDEFINED;
770 chunk_t skd = chunk_empty;
771 ike_sa_id_t *id;
772
773 id = this->ike_sa->get_id(this->ike_sa);
774 if (this->old_sa)
775 {
776 /* rekeying: Include old SKd, use old PRF, apply SPI */
777 old_keymat = (keymat_v2_t*)this->old_sa->get_keymat(this->old_sa);
778 prf_alg = old_keymat->get_skd(old_keymat, &skd);
779 if (this->initiator)
780 {
781 id->set_responder_spi(id, this->proposal->get_spi(this->proposal));
782 }
783 else
784 {
785 id->set_initiator_spi(id, this->proposal->get_spi(this->proposal));
786 }
787 }
788 if (!this->keymat->derive_ike_keys(this->keymat, this->proposal, this->dh,
789 nonce_i, nonce_r, id, prf_alg, skd))
790 {
791 return FALSE;
792 }
793 charon->bus->ike_keys(charon->bus, this->ike_sa, this->dh, chunk_empty,
794 nonce_i, nonce_r, this->old_sa, NULL, AUTH_NONE);
795 return TRUE;
796 }
797
798 METHOD(task_t, build_r, status_t,
799 private_ike_init_t *this, message_t *message)
800 {
801 identification_t *gateway;
802
803 /* check if we have everything we need */
804 if (this->proposal == NULL ||
805 this->other_nonce.len == 0 || this->my_nonce.len == 0)
806 {
807 DBG1(DBG_IKE, "received proposals unacceptable");
808 message->add_notify(message, TRUE, NO_PROPOSAL_CHOSEN, chunk_empty);
809 return FAILED;
810 }
811
812 /* check if we'd have to redirect the client */
813 if (!this->old_sa &&
814 this->ike_sa->supports_extension(this->ike_sa, EXT_IKE_REDIRECTION) &&
815 charon->redirect->redirect_on_init(charon->redirect, this->ike_sa,
816 &gateway))
817 {
818 chunk_t data;
819
820 DBG1(DBG_IKE, "redirecting peer to %Y", gateway);
821 data = redirect_data_create(gateway, this->other_nonce);
822 message->add_notify(message, TRUE, REDIRECT, data);
823 gateway->destroy(gateway);
824 chunk_free(&data);
825 return FAILED;
826 }
827
828 if (this->dh == NULL ||
829 !this->proposal->has_dh_group(this->proposal, this->dh_group))
830 {
831 uint16_t group;
832
833 if (this->proposal->get_algorithm(this->proposal, DIFFIE_HELLMAN_GROUP,
834 &group, NULL))
835 {
836 DBG1(DBG_IKE, "DH group %N unacceptable, requesting %N",
837 diffie_hellman_group_names, this->dh_group,
838 diffie_hellman_group_names, group);
839 this->dh_group = group;
840 group = htons(group);
841 message->add_notify(message, FALSE, INVALID_KE_PAYLOAD,
842 chunk_from_thing(group));
843 }
844 else
845 {
846 DBG1(DBG_IKE, "no acceptable proposal found");
847 message->add_notify(message, TRUE, NO_PROPOSAL_CHOSEN, chunk_empty);
848 }
849 return FAILED;
850 }
851
852 if (this->dh_failed)
853 {
854 DBG1(DBG_IKE, "applying DH public value failed");
855 message->add_notify(message, TRUE, NO_PROPOSAL_CHOSEN, chunk_empty);
856 return FAILED;
857 }
858
859 if (!derive_keys(this, this->other_nonce, this->my_nonce))
860 {
861 DBG1(DBG_IKE, "key derivation failed");
862 message->add_notify(message, TRUE, NO_PROPOSAL_CHOSEN, chunk_empty);
863 return FAILED;
864 }
865 if (!build_payloads(this, message))
866 {
867 message->add_notify(message, TRUE, NO_PROPOSAL_CHOSEN, chunk_empty);
868 return FAILED;
869 }
870 return SUCCESS;
871 }
872
873 /**
874 * Raise alerts for received notify errors
875 */
876 static void raise_alerts(private_ike_init_t *this, notify_type_t type)
877 {
878 ike_cfg_t *ike_cfg;
879 linked_list_t *list;
880
881 switch (type)
882 {
883 case NO_PROPOSAL_CHOSEN:
884 ike_cfg = this->ike_sa->get_ike_cfg(this->ike_sa);
885 list = ike_cfg->get_proposals(ike_cfg);
886 charon->bus->alert(charon->bus, ALERT_PROPOSAL_MISMATCH_IKE, list);
887 list->destroy_offset(list, offsetof(proposal_t, destroy));
888 break;
889 default:
890 break;
891 }
892 }
893
894 METHOD(task_t, pre_process_i, status_t,
895 private_ike_init_t *this, message_t *message)
896 {
897 enumerator_t *enumerator;
898 payload_t *payload;
899
900 /* check for erroneous notifies */
901 enumerator = message->create_payload_enumerator(message);
902 while (enumerator->enumerate(enumerator, &payload))
903 {
904 if (payload->get_type(payload) == PLV2_NOTIFY)
905 {
906 notify_payload_t *notify = (notify_payload_t*)payload;
907 notify_type_t type = notify->get_notify_type(notify);
908
909 switch (type)
910 {
911 case COOKIE:
912 {
913 chunk_t cookie;
914
915 cookie = notify->get_notification_data(notify);
916 if (chunk_equals(cookie, this->cookie))
917 {
918 DBG1(DBG_IKE, "ignore response with duplicate COOKIE "
919 "notify");
920 enumerator->destroy(enumerator);
921 return FAILED;
922 }
923 break;
924 }
925 case REDIRECT:
926 {
927 identification_t *gateway;
928 chunk_t data, nonce = chunk_empty;
929 status_t status = SUCCESS;
930
931 if (this->old_sa)
932 {
933 break;
934 }
935 data = notify->get_notification_data(notify);
936 gateway = redirect_data_parse(data, &nonce);
937 if (!gateway || !chunk_equals(nonce, this->my_nonce))
938 {
939 DBG1(DBG_IKE, "received invalid REDIRECT notify");
940 status = FAILED;
941 }
942 DESTROY_IF(gateway);
943 chunk_free(&nonce);
944 enumerator->destroy(enumerator);
945 return status;
946 }
947 default:
948 break;
949 }
950 }
951 }
952 enumerator->destroy(enumerator);
953 return SUCCESS;
954 }
955
956 METHOD(task_t, process_i, status_t,
957 private_ike_init_t *this, message_t *message)
958 {
959 enumerator_t *enumerator;
960 payload_t *payload;
961
962 /* check for erroneous notifies */
963 enumerator = message->create_payload_enumerator(message);
964 while (enumerator->enumerate(enumerator, &payload))
965 {
966 if (payload->get_type(payload) == PLV2_NOTIFY)
967 {
968 notify_payload_t *notify = (notify_payload_t*)payload;
969 notify_type_t type = notify->get_notify_type(notify);
970
971 switch (type)
972 {
973 case INVALID_KE_PAYLOAD:
974 {
975 chunk_t data;
976 diffie_hellman_group_t bad_group;
977
978 bad_group = this->dh_group;
979 data = notify->get_notification_data(notify);
980 this->dh_group = ntohs(*((uint16_t*)data.ptr));
981 DBG1(DBG_IKE, "peer didn't accept DH group %N, "
982 "it requested %N", diffie_hellman_group_names,
983 bad_group, diffie_hellman_group_names, this->dh_group);
984
985 if (this->old_sa == NULL)
986 { /* reset the IKE_SA if we are not rekeying */
987 this->ike_sa->reset(this->ike_sa, FALSE);
988 }
989
990 enumerator->destroy(enumerator);
991 this->retry++;
992 return NEED_MORE;
993 }
994 case NAT_DETECTION_SOURCE_IP:
995 case NAT_DETECTION_DESTINATION_IP:
996 /* skip, handled in ike_natd_t */
997 break;
998 case MULTIPLE_AUTH_SUPPORTED:
999 /* handled in ike_auth_t */
1000 break;
1001 case COOKIE:
1002 {
1003 chunk_free(&this->cookie);
1004 this->cookie = chunk_clone(notify->get_notification_data(notify));
1005 this->ike_sa->reset(this->ike_sa, FALSE);
1006 enumerator->destroy(enumerator);
1007 DBG2(DBG_IKE, "received %N notify", notify_type_names, type);
1008 this->retry++;
1009 return NEED_MORE;
1010 }
1011 case REDIRECT:
1012 {
1013 identification_t *gateway;
1014 chunk_t data, nonce = chunk_empty;
1015 status_t status = FAILED;
1016
1017 if (this->old_sa)
1018 {
1019 DBG1(DBG_IKE, "received REDIRECT notify during rekeying"
1020 ", ignored");
1021 break;
1022 }
1023 data = notify->get_notification_data(notify);
1024 gateway = redirect_data_parse(data, &nonce);
1025 if (this->ike_sa->handle_redirect(this->ike_sa, gateway))
1026 {
1027 status = NEED_MORE;
1028 }
1029 DESTROY_IF(gateway);
1030 chunk_free(&nonce);
1031 enumerator->destroy(enumerator);
1032 return status;
1033 }
1034 default:
1035 {
1036 if (type <= 16383)
1037 {
1038 DBG1(DBG_IKE, "received %N notify error",
1039 notify_type_names, type);
1040 enumerator->destroy(enumerator);
1041 raise_alerts(this, type);
1042 return FAILED;
1043 }
1044 DBG2(DBG_IKE, "received %N notify",
1045 notify_type_names, type);
1046 break;
1047 }
1048 }
1049 }
1050 }
1051 enumerator->destroy(enumerator);
1052
1053 process_payloads(this, message);
1054
1055 /* check if we have everything */
1056 if (this->proposal == NULL ||
1057 this->other_nonce.len == 0 || this->my_nonce.len == 0)
1058 {
1059 DBG1(DBG_IKE, "peers proposal selection invalid");
1060 return FAILED;
1061 }
1062
1063 if (this->dh == NULL ||
1064 !this->proposal->has_dh_group(this->proposal, this->dh_group))
1065 {
1066 DBG1(DBG_IKE, "peer DH group selection invalid");
1067 return FAILED;
1068 }
1069
1070 if (this->dh_failed)
1071 {
1072 DBG1(DBG_IKE, "applying DH public value failed");
1073 return FAILED;
1074 }
1075
1076 if (!derive_keys(this, this->my_nonce, this->other_nonce))
1077 {
1078 DBG1(DBG_IKE, "key derivation failed");
1079 return FAILED;
1080 }
1081 return SUCCESS;
1082 }
1083
1084 METHOD(task_t, get_type, task_type_t,
1085 private_ike_init_t *this)
1086 {
1087 return TASK_IKE_INIT;
1088 }
1089
1090 METHOD(task_t, migrate, void,
1091 private_ike_init_t *this, ike_sa_t *ike_sa)
1092 {
1093 DESTROY_IF(this->proposal);
1094 chunk_free(&this->other_nonce);
1095
1096 this->ike_sa = ike_sa;
1097 this->keymat = (keymat_v2_t*)ike_sa->get_keymat(ike_sa);
1098 this->proposal = NULL;
1099 this->dh_failed = FALSE;
1100 }
1101
1102 METHOD(task_t, destroy, void,
1103 private_ike_init_t *this)
1104 {
1105 DESTROY_IF(this->dh);
1106 DESTROY_IF(this->proposal);
1107 DESTROY_IF(this->nonceg);
1108 chunk_free(&this->my_nonce);
1109 chunk_free(&this->other_nonce);
1110 chunk_free(&this->cookie);
1111 free(this);
1112 }
1113
1114 METHOD(ike_init_t, get_lower_nonce, chunk_t,
1115 private_ike_init_t *this)
1116 {
1117 if (memcmp(this->my_nonce.ptr, this->other_nonce.ptr,
1118 min(this->my_nonce.len, this->other_nonce.len)) < 0)
1119 {
1120 return this->my_nonce;
1121 }
1122 else
1123 {
1124 return this->other_nonce;
1125 }
1126 }
1127
1128 /*
1129 * Described in header.
1130 */
1131 ike_init_t *ike_init_create(ike_sa_t *ike_sa, bool initiator, ike_sa_t *old_sa)
1132 {
1133 private_ike_init_t *this;
1134
1135 INIT(this,
1136 .public = {
1137 .task = {
1138 .get_type = _get_type,
1139 .migrate = _migrate,
1140 .destroy = _destroy,
1141 },
1142 .get_lower_nonce = _get_lower_nonce,
1143 },
1144 .ike_sa = ike_sa,
1145 .initiator = initiator,
1146 .dh_group = MODP_NONE,
1147 .keymat = (keymat_v2_t*)ike_sa->get_keymat(ike_sa),
1148 .old_sa = old_sa,
1149 .signature_authentication = lib->settings->get_bool(lib->settings,
1150 "%s.signature_authentication", TRUE, lib->ns),
1151 .follow_redirects = lib->settings->get_bool(lib->settings,
1152 "%s.follow_redirects", TRUE, lib->ns),
1153 );
1154 this->nonceg = this->keymat->keymat.create_nonce_gen(&this->keymat->keymat);
1155
1156 if (initiator)
1157 {
1158 this->public.task.build = _build_i;
1159 this->public.task.process = _process_i;
1160 this->public.task.pre_process = _pre_process_i;
1161 }
1162 else
1163 {
1164 this->public.task.build = _build_r;
1165 this->public.task.process = _process_r;
1166 }
1167 return &this->public;
1168 }
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