proposal-substructure: Fix incorrect type for IKEv2 proposals
[strongswan.git] / src / libcharon / sa / ikev2 / tasks / ike_init.c
1 /*
2 * Copyright (C) 2008-2018 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 return TRUE;
437 }
438
439 /**
440 * Process the SA payload and select a proposal
441 */
442 static void process_sa_payload(private_ike_init_t *this, message_t *message,
443 sa_payload_t *sa_payload)
444 {
445 ike_cfg_t *ike_cfg, *cfg, *alt_cfg = NULL;
446 enumerator_t *enumerator;
447 linked_list_t *proposal_list;
448 host_t *me, *other;
449 bool private, prefer_configured;
450
451 ike_cfg = this->ike_sa->get_ike_cfg(this->ike_sa);
452
453 proposal_list = sa_payload->get_proposals(sa_payload);
454 private = this->ike_sa->supports_extension(this->ike_sa, EXT_STRONGSWAN);
455 prefer_configured = lib->settings->get_bool(lib->settings,
456 "%s.prefer_configured_proposals", TRUE, lib->ns);
457
458 this->proposal = ike_cfg->select_proposal(ike_cfg, proposal_list, private,
459 prefer_configured);
460 if (!this->proposal)
461 {
462 if (!this->initiator && !this->old_sa)
463 {
464 me = message->get_destination(message);
465 other = message->get_source(message);
466 enumerator = charon->backends->create_ike_cfg_enumerator(
467 charon->backends, me, other, IKEV2);
468 while (enumerator->enumerate(enumerator, &cfg))
469 {
470 if (ike_cfg == cfg)
471 { /* already tried and failed */
472 continue;
473 }
474 DBG1(DBG_IKE, "no matching proposal found, trying alternative "
475 "config");
476 this->proposal = cfg->select_proposal(cfg, proposal_list,
477 private, prefer_configured);
478 if (this->proposal)
479 {
480 alt_cfg = cfg->get_ref(cfg);
481 break;
482 }
483 }
484 enumerator->destroy(enumerator);
485 }
486 if (alt_cfg)
487 {
488 this->ike_sa->set_ike_cfg(this->ike_sa, alt_cfg);
489 alt_cfg->destroy(alt_cfg);
490 }
491 else
492 {
493 charon->bus->alert(charon->bus, ALERT_PROPOSAL_MISMATCH_IKE,
494 proposal_list);
495 }
496 }
497 proposal_list->destroy_offset(proposal_list,
498 offsetof(proposal_t, destroy));
499 }
500
501 /**
502 * Read payloads from message
503 */
504 static void process_payloads(private_ike_init_t *this, message_t *message)
505 {
506 enumerator_t *enumerator;
507 payload_t *payload;
508 ke_payload_t *ke_payload = NULL;
509
510 enumerator = message->create_payload_enumerator(message);
511 while (enumerator->enumerate(enumerator, &payload))
512 {
513 switch (payload->get_type(payload))
514 {
515 case PLV2_SECURITY_ASSOCIATION:
516 {
517 process_sa_payload(this, message, (sa_payload_t*)payload);
518 break;
519 }
520 case PLV2_KEY_EXCHANGE:
521 {
522 ke_payload = (ke_payload_t*)payload;
523
524 this->dh_group = ke_payload->get_dh_group_number(ke_payload);
525 break;
526 }
527 case PLV2_NONCE:
528 {
529 nonce_payload_t *nonce_payload = (nonce_payload_t*)payload;
530
531 this->other_nonce = nonce_payload->get_nonce(nonce_payload);
532 break;
533 }
534 case PLV2_NOTIFY:
535 {
536 notify_payload_t *notify = (notify_payload_t*)payload;
537
538 switch (notify->get_notify_type(notify))
539 {
540 case FRAGMENTATION_SUPPORTED:
541 this->ike_sa->enable_extension(this->ike_sa,
542 EXT_IKE_FRAGMENTATION);
543 break;
544 case SIGNATURE_HASH_ALGORITHMS:
545 if (this->signature_authentication)
546 {
547 handle_supported_hash_algorithms(this, notify);
548 }
549 break;
550 case USE_PPK:
551 if (!this->old_sa)
552 {
553 this->ike_sa->enable_extension(this->ike_sa,
554 EXT_PPK);
555 }
556 break;
557 case REDIRECTED_FROM:
558 {
559 identification_t *gateway;
560 chunk_t data;
561
562 data = notify->get_notification_data(notify);
563 gateway = redirect_data_parse(data, NULL);
564 if (!gateway)
565 {
566 DBG1(DBG_IKE, "received invalid REDIRECTED_FROM "
567 "notify, ignored");
568 break;
569 }
570 DBG1(DBG_IKE, "client got redirected from %Y", gateway);
571 gateway->destroy(gateway);
572 /* fall-through */
573 }
574 case REDIRECT_SUPPORTED:
575 if (!this->old_sa)
576 {
577 this->ike_sa->enable_extension(this->ike_sa,
578 EXT_IKE_REDIRECTION);
579 }
580 break;
581 default:
582 /* other notifies are handled elsewhere */
583 break;
584 }
585
586 }
587 default:
588 break;
589 }
590 }
591 enumerator->destroy(enumerator);
592
593 if (this->proposal)
594 {
595 this->ike_sa->set_proposal(this->ike_sa, this->proposal);
596 }
597
598 if (ke_payload && this->proposal &&
599 this->proposal->has_dh_group(this->proposal, this->dh_group))
600 {
601 if (!this->initiator)
602 {
603 this->dh = this->keymat->keymat.create_dh(
604 &this->keymat->keymat, this->dh_group);
605 }
606 else if (this->dh)
607 {
608 this->dh_failed = this->dh->get_dh_group(this->dh) != this->dh_group;
609 }
610 if (this->dh && !this->dh_failed)
611 {
612 this->dh_failed = !this->dh->set_other_public_value(this->dh,
613 ke_payload->get_key_exchange_data(ke_payload));
614 }
615 }
616 }
617
618 METHOD(task_t, build_i, status_t,
619 private_ike_init_t *this, message_t *message)
620 {
621 ike_cfg_t *ike_cfg;
622
623 ike_cfg = this->ike_sa->get_ike_cfg(this->ike_sa);
624
625 DBG0(DBG_IKE, "initiating IKE_SA %s[%d] to %H",
626 this->ike_sa->get_name(this->ike_sa),
627 this->ike_sa->get_unique_id(this->ike_sa),
628 this->ike_sa->get_other_host(this->ike_sa));
629 this->ike_sa->set_state(this->ike_sa, IKE_CONNECTING);
630
631 if (this->retry >= MAX_RETRIES)
632 {
633 DBG1(DBG_IKE, "giving up after %d retries", MAX_RETRIES);
634 return FAILED;
635 }
636
637 /* if we are retrying after an INVALID_KE_PAYLOAD we already have one */
638 if (!this->dh)
639 {
640 if (this->old_sa && lib->settings->get_bool(lib->settings,
641 "%s.prefer_previous_dh_group", TRUE, lib->ns))
642 { /* reuse the DH group we used for the old IKE_SA when rekeying */
643 proposal_t *proposal;
644 uint16_t dh_group;
645
646 proposal = this->old_sa->get_proposal(this->old_sa);
647 if (proposal->get_algorithm(proposal, DIFFIE_HELLMAN_GROUP,
648 &dh_group, NULL))
649 {
650 this->dh_group = dh_group;
651 }
652 else
653 { /* this shouldn't happen, but let's be safe */
654 this->dh_group = ike_cfg->get_dh_group(ike_cfg);
655 }
656 }
657 else
658 {
659 this->dh_group = ike_cfg->get_dh_group(ike_cfg);
660 }
661 this->dh = this->keymat->keymat.create_dh(&this->keymat->keymat,
662 this->dh_group);
663 if (!this->dh)
664 {
665 DBG1(DBG_IKE, "configured DH group %N not supported",
666 diffie_hellman_group_names, this->dh_group);
667 return FAILED;
668 }
669 }
670 else if (this->dh->get_dh_group(this->dh) != this->dh_group)
671 { /* reset DH instance if group changed (INVALID_KE_PAYLOAD) */
672 this->dh->destroy(this->dh);
673 this->dh = this->keymat->keymat.create_dh(&this->keymat->keymat,
674 this->dh_group);
675 if (!this->dh)
676 {
677 DBG1(DBG_IKE, "requested DH group %N not supported",
678 diffie_hellman_group_names, this->dh_group);
679 return FAILED;
680 }
681 }
682
683 /* generate nonce only when we are trying the first time */
684 if (this->my_nonce.ptr == NULL)
685 {
686 if (!generate_nonce(this))
687 {
688 return FAILED;
689 }
690 }
691
692 if (this->cookie.ptr)
693 {
694 message->add_notify(message, FALSE, COOKIE, this->cookie);
695 }
696
697 if (!build_payloads(this, message))
698 {
699 return FAILED;
700 }
701
702 #ifdef ME
703 {
704 chunk_t connect_id = this->ike_sa->get_connect_id(this->ike_sa);
705 if (connect_id.ptr)
706 {
707 message->add_notify(message, FALSE, ME_CONNECTID, connect_id);
708 }
709 }
710 #endif /* ME */
711
712 return NEED_MORE;
713 }
714
715 METHOD(task_t, process_r, status_t,
716 private_ike_init_t *this, message_t *message)
717 {
718 DBG0(DBG_IKE, "%H is initiating an IKE_SA", message->get_source(message));
719 this->ike_sa->set_state(this->ike_sa, IKE_CONNECTING);
720
721 if (!generate_nonce(this))
722 {
723 return FAILED;
724 }
725
726 #ifdef ME
727 {
728 notify_payload_t *notify = message->get_notify(message, ME_CONNECTID);
729 if (notify)
730 {
731 chunk_t connect_id = notify->get_notification_data(notify);
732 DBG2(DBG_IKE, "received ME_CONNECTID %#B", &connect_id);
733 charon->connect_manager->stop_checks(charon->connect_manager,
734 connect_id);
735 }
736 }
737 #endif /* ME */
738
739 process_payloads(this, message);
740
741 return NEED_MORE;
742 }
743
744 /**
745 * Derive the keymat for the IKE_SA
746 */
747 static bool derive_keys(private_ike_init_t *this,
748 chunk_t nonce_i, chunk_t nonce_r)
749 {
750 keymat_v2_t *old_keymat;
751 pseudo_random_function_t prf_alg = PRF_UNDEFINED;
752 chunk_t skd = chunk_empty;
753 ike_sa_id_t *id;
754
755 id = this->ike_sa->get_id(this->ike_sa);
756 if (this->old_sa)
757 {
758 /* rekeying: Include old SKd, use old PRF, apply SPI */
759 old_keymat = (keymat_v2_t*)this->old_sa->get_keymat(this->old_sa);
760 prf_alg = old_keymat->get_skd(old_keymat, &skd);
761 if (this->initiator)
762 {
763 id->set_responder_spi(id, this->proposal->get_spi(this->proposal));
764 }
765 else
766 {
767 id->set_initiator_spi(id, this->proposal->get_spi(this->proposal));
768 }
769 }
770 if (!this->keymat->derive_ike_keys(this->keymat, this->proposal, this->dh,
771 nonce_i, nonce_r, id, prf_alg, skd))
772 {
773 return FALSE;
774 }
775 charon->bus->ike_keys(charon->bus, this->ike_sa, this->dh, chunk_empty,
776 nonce_i, nonce_r, this->old_sa, NULL, AUTH_NONE);
777 return TRUE;
778 }
779
780 METHOD(task_t, build_r, status_t,
781 private_ike_init_t *this, message_t *message)
782 {
783 identification_t *gateway;
784
785 /* check if we have everything we need */
786 if (this->proposal == NULL ||
787 this->other_nonce.len == 0 || this->my_nonce.len == 0)
788 {
789 DBG1(DBG_IKE, "received proposals unacceptable");
790 message->add_notify(message, TRUE, NO_PROPOSAL_CHOSEN, chunk_empty);
791 return FAILED;
792 }
793
794 /* check if we'd have to redirect the client */
795 if (!this->old_sa &&
796 this->ike_sa->supports_extension(this->ike_sa, EXT_IKE_REDIRECTION) &&
797 charon->redirect->redirect_on_init(charon->redirect, this->ike_sa,
798 &gateway))
799 {
800 chunk_t data;
801
802 DBG1(DBG_IKE, "redirecting peer to %Y", gateway);
803 data = redirect_data_create(gateway, this->other_nonce);
804 message->add_notify(message, TRUE, REDIRECT, data);
805 gateway->destroy(gateway);
806 chunk_free(&data);
807 return FAILED;
808 }
809
810 if (this->dh == NULL ||
811 !this->proposal->has_dh_group(this->proposal, this->dh_group))
812 {
813 uint16_t group;
814
815 if (this->proposal->get_algorithm(this->proposal, DIFFIE_HELLMAN_GROUP,
816 &group, NULL))
817 {
818 DBG1(DBG_IKE, "DH group %N unacceptable, requesting %N",
819 diffie_hellman_group_names, this->dh_group,
820 diffie_hellman_group_names, group);
821 this->dh_group = group;
822 group = htons(group);
823 message->add_notify(message, FALSE, INVALID_KE_PAYLOAD,
824 chunk_from_thing(group));
825 }
826 else
827 {
828 DBG1(DBG_IKE, "no acceptable proposal found");
829 message->add_notify(message, TRUE, NO_PROPOSAL_CHOSEN, chunk_empty);
830 }
831 return FAILED;
832 }
833
834 if (this->dh_failed)
835 {
836 DBG1(DBG_IKE, "applying DH public value failed");
837 message->add_notify(message, TRUE, NO_PROPOSAL_CHOSEN, chunk_empty);
838 return FAILED;
839 }
840
841 if (!derive_keys(this, this->other_nonce, this->my_nonce))
842 {
843 DBG1(DBG_IKE, "key derivation failed");
844 message->add_notify(message, TRUE, NO_PROPOSAL_CHOSEN, chunk_empty);
845 return FAILED;
846 }
847 if (!build_payloads(this, message))
848 {
849 message->add_notify(message, TRUE, NO_PROPOSAL_CHOSEN, chunk_empty);
850 return FAILED;
851 }
852 return SUCCESS;
853 }
854
855 /**
856 * Raise alerts for received notify errors
857 */
858 static void raise_alerts(private_ike_init_t *this, notify_type_t type)
859 {
860 ike_cfg_t *ike_cfg;
861 linked_list_t *list;
862
863 switch (type)
864 {
865 case NO_PROPOSAL_CHOSEN:
866 ike_cfg = this->ike_sa->get_ike_cfg(this->ike_sa);
867 list = ike_cfg->get_proposals(ike_cfg);
868 charon->bus->alert(charon->bus, ALERT_PROPOSAL_MISMATCH_IKE, list);
869 list->destroy_offset(list, offsetof(proposal_t, destroy));
870 break;
871 default:
872 break;
873 }
874 }
875
876 METHOD(task_t, pre_process_i, status_t,
877 private_ike_init_t *this, message_t *message)
878 {
879 enumerator_t *enumerator;
880 payload_t *payload;
881
882 /* check for erroneous notifies */
883 enumerator = message->create_payload_enumerator(message);
884 while (enumerator->enumerate(enumerator, &payload))
885 {
886 if (payload->get_type(payload) == PLV2_NOTIFY)
887 {
888 notify_payload_t *notify = (notify_payload_t*)payload;
889 notify_type_t type = notify->get_notify_type(notify);
890
891 switch (type)
892 {
893 case COOKIE:
894 {
895 chunk_t cookie;
896
897 cookie = notify->get_notification_data(notify);
898 if (chunk_equals(cookie, this->cookie))
899 {
900 DBG1(DBG_IKE, "ignore response with duplicate COOKIE "
901 "notify");
902 enumerator->destroy(enumerator);
903 return FAILED;
904 }
905 break;
906 }
907 case REDIRECT:
908 {
909 identification_t *gateway;
910 chunk_t data, nonce = chunk_empty;
911 status_t status = SUCCESS;
912
913 if (this->old_sa)
914 {
915 break;
916 }
917 data = notify->get_notification_data(notify);
918 gateway = redirect_data_parse(data, &nonce);
919 if (!gateway || !chunk_equals(nonce, this->my_nonce))
920 {
921 DBG1(DBG_IKE, "received invalid REDIRECT notify");
922 status = FAILED;
923 }
924 DESTROY_IF(gateway);
925 chunk_free(&nonce);
926 enumerator->destroy(enumerator);
927 return status;
928 }
929 default:
930 break;
931 }
932 }
933 }
934 enumerator->destroy(enumerator);
935 return SUCCESS;
936 }
937
938 METHOD(task_t, process_i, status_t,
939 private_ike_init_t *this, message_t *message)
940 {
941 enumerator_t *enumerator;
942 payload_t *payload;
943
944 /* check for erroneous notifies */
945 enumerator = message->create_payload_enumerator(message);
946 while (enumerator->enumerate(enumerator, &payload))
947 {
948 if (payload->get_type(payload) == PLV2_NOTIFY)
949 {
950 notify_payload_t *notify = (notify_payload_t*)payload;
951 notify_type_t type = notify->get_notify_type(notify);
952
953 switch (type)
954 {
955 case INVALID_KE_PAYLOAD:
956 {
957 chunk_t data;
958 diffie_hellman_group_t bad_group;
959
960 bad_group = this->dh_group;
961 data = notify->get_notification_data(notify);
962 this->dh_group = ntohs(*((uint16_t*)data.ptr));
963 DBG1(DBG_IKE, "peer didn't accept DH group %N, "
964 "it requested %N", diffie_hellman_group_names,
965 bad_group, diffie_hellman_group_names, this->dh_group);
966
967 if (this->old_sa == NULL)
968 { /* reset the IKE_SA if we are not rekeying */
969 this->ike_sa->reset(this->ike_sa, FALSE);
970 }
971
972 enumerator->destroy(enumerator);
973 this->retry++;
974 return NEED_MORE;
975 }
976 case NAT_DETECTION_SOURCE_IP:
977 case NAT_DETECTION_DESTINATION_IP:
978 /* skip, handled in ike_natd_t */
979 break;
980 case MULTIPLE_AUTH_SUPPORTED:
981 /* handled in ike_auth_t */
982 break;
983 case COOKIE:
984 {
985 chunk_free(&this->cookie);
986 this->cookie = chunk_clone(notify->get_notification_data(notify));
987 this->ike_sa->reset(this->ike_sa, FALSE);
988 enumerator->destroy(enumerator);
989 DBG2(DBG_IKE, "received %N notify", notify_type_names, type);
990 this->retry++;
991 return NEED_MORE;
992 }
993 case REDIRECT:
994 {
995 identification_t *gateway;
996 chunk_t data, nonce = chunk_empty;
997 status_t status = FAILED;
998
999 if (this->old_sa)
1000 {
1001 DBG1(DBG_IKE, "received REDIRECT notify during rekeying"
1002 ", ignored");
1003 break;
1004 }
1005 data = notify->get_notification_data(notify);
1006 gateway = redirect_data_parse(data, &nonce);
1007 if (this->ike_sa->handle_redirect(this->ike_sa, gateway))
1008 {
1009 status = NEED_MORE;
1010 }
1011 DESTROY_IF(gateway);
1012 chunk_free(&nonce);
1013 enumerator->destroy(enumerator);
1014 return status;
1015 }
1016 default:
1017 {
1018 if (type <= 16383)
1019 {
1020 DBG1(DBG_IKE, "received %N notify error",
1021 notify_type_names, type);
1022 enumerator->destroy(enumerator);
1023 raise_alerts(this, type);
1024 return FAILED;
1025 }
1026 DBG2(DBG_IKE, "received %N notify",
1027 notify_type_names, type);
1028 break;
1029 }
1030 }
1031 }
1032 }
1033 enumerator->destroy(enumerator);
1034
1035 process_payloads(this, message);
1036
1037 /* check if we have everything */
1038 if (this->proposal == NULL ||
1039 this->other_nonce.len == 0 || this->my_nonce.len == 0)
1040 {
1041 DBG1(DBG_IKE, "peers proposal selection invalid");
1042 return FAILED;
1043 }
1044
1045 if (this->dh == NULL ||
1046 !this->proposal->has_dh_group(this->proposal, this->dh_group))
1047 {
1048 DBG1(DBG_IKE, "peer DH group selection invalid");
1049 return FAILED;
1050 }
1051
1052 if (this->dh_failed)
1053 {
1054 DBG1(DBG_IKE, "applying DH public value failed");
1055 return FAILED;
1056 }
1057
1058 if (!derive_keys(this, this->my_nonce, this->other_nonce))
1059 {
1060 DBG1(DBG_IKE, "key derivation failed");
1061 return FAILED;
1062 }
1063 return SUCCESS;
1064 }
1065
1066 METHOD(task_t, get_type, task_type_t,
1067 private_ike_init_t *this)
1068 {
1069 return TASK_IKE_INIT;
1070 }
1071
1072 METHOD(task_t, migrate, void,
1073 private_ike_init_t *this, ike_sa_t *ike_sa)
1074 {
1075 DESTROY_IF(this->proposal);
1076 chunk_free(&this->other_nonce);
1077
1078 this->ike_sa = ike_sa;
1079 this->keymat = (keymat_v2_t*)ike_sa->get_keymat(ike_sa);
1080 this->proposal = NULL;
1081 this->dh_failed = FALSE;
1082 }
1083
1084 METHOD(task_t, destroy, void,
1085 private_ike_init_t *this)
1086 {
1087 DESTROY_IF(this->dh);
1088 DESTROY_IF(this->proposal);
1089 DESTROY_IF(this->nonceg);
1090 chunk_free(&this->my_nonce);
1091 chunk_free(&this->other_nonce);
1092 chunk_free(&this->cookie);
1093 free(this);
1094 }
1095
1096 METHOD(ike_init_t, get_lower_nonce, chunk_t,
1097 private_ike_init_t *this)
1098 {
1099 if (memcmp(this->my_nonce.ptr, this->other_nonce.ptr,
1100 min(this->my_nonce.len, this->other_nonce.len)) < 0)
1101 {
1102 return this->my_nonce;
1103 }
1104 else
1105 {
1106 return this->other_nonce;
1107 }
1108 }
1109
1110 /*
1111 * Described in header.
1112 */
1113 ike_init_t *ike_init_create(ike_sa_t *ike_sa, bool initiator, ike_sa_t *old_sa)
1114 {
1115 private_ike_init_t *this;
1116
1117 INIT(this,
1118 .public = {
1119 .task = {
1120 .get_type = _get_type,
1121 .migrate = _migrate,
1122 .destroy = _destroy,
1123 },
1124 .get_lower_nonce = _get_lower_nonce,
1125 },
1126 .ike_sa = ike_sa,
1127 .initiator = initiator,
1128 .dh_group = MODP_NONE,
1129 .keymat = (keymat_v2_t*)ike_sa->get_keymat(ike_sa),
1130 .old_sa = old_sa,
1131 .signature_authentication = lib->settings->get_bool(lib->settings,
1132 "%s.signature_authentication", TRUE, lib->ns),
1133 .follow_redirects = lib->settings->get_bool(lib->settings,
1134 "%s.follow_redirects", TRUE, lib->ns),
1135 );
1136 this->nonceg = this->keymat->keymat.create_nonce_gen(&this->keymat->keymat);
1137
1138 if (initiator)
1139 {
1140 this->public.task.build = _build_i;
1141 this->public.task.process = _process_i;
1142 this->public.task.pre_process = _pre_process_i;
1143 }
1144 else
1145 {
1146 this->public.task.build = _build_r;
1147 this->public.task.process = _process_r;
1148 }
1149 return &this->public;
1150 }