xref: /openbsd-src/sbin/isakmpd/ipsec.c (revision d13be5d47e4149db2549a9828e244d59dbc43f15)
1 /* $OpenBSD: ipsec.c,v 1.136 2010/09/22 13:45:15 mikeb Exp $	 */
2 /* $EOM: ipsec.c,v 1.143 2000/12/11 23:57:42 niklas Exp $	 */
3 
4 /*
5  * Copyright (c) 1998, 1999, 2000, 2001 Niklas Hallqvist.  All rights reserved.
6  * Copyright (c) 2001 Angelos D. Keromytis.  All rights reserved.
7  * Copyright (c) 2001 H�kan Olsson.  All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28  */
29 
30 /*
31  * This code was written under funding by Ericsson Radio Systems.
32  */
33 
34 #include <sys/types.h>
35 #include <sys/socket.h>
36 #include <netdb.h>
37 #include <netinet/in.h>
38 #include <arpa/inet.h>
39 #include <stdlib.h>
40 #include <string.h>
41 
42 #include <net/if.h>
43 #include <net/pfvar.h>
44 
45 #include "sysdep.h"
46 
47 #include "attribute.h"
48 #include "conf.h"
49 #include "connection.h"
50 #include "constants.h"
51 #include "crypto.h"
52 #include "dh.h"
53 #include "doi.h"
54 #include "dpd.h"
55 #include "exchange.h"
56 #include "hash.h"
57 #include "ike_aggressive.h"
58 #include "ike_auth.h"
59 #include "ike_main_mode.h"
60 #include "ike_quick_mode.h"
61 #include "ipsec.h"
62 #include "ipsec_doi.h"
63 #include "isakmp.h"
64 #include "isakmp_cfg.h"
65 #include "isakmp_fld.h"
66 #include "isakmp_num.h"
67 #include "log.h"
68 #include "message.h"
69 #include "nat_traversal.h"
70 #include "pf_key_v2.h"
71 #include "prf.h"
72 #include "sa.h"
73 #include "timer.h"
74 #include "transport.h"
75 #include "util.h"
76 #include "x509.h"
77 
78 extern int acquire_only;
79 
80 /* Backwards compatibility.  */
81 #ifndef NI_MAXHOST
82 #define NI_MAXHOST 1025
83 #endif
84 
85 /* The replay window size used for all IPsec protocols if not overridden.  */
86 #define DEFAULT_REPLAY_WINDOW 16
87 
88 struct ipsec_decode_arg {
89 	struct message *msg;
90 	struct sa      *sa;
91 	struct proto   *proto;
92 };
93 
94 /* These variables hold the contacted peers ADT state.  */
95 struct contact {
96 	struct sockaddr *addr;
97 	socklen_t       len;
98 }              *contacts = 0;
99 int             contact_cnt = 0, contact_limit = 0;
100 
101 static int      addr_cmp(const void *, const void *);
102 static int      ipsec_add_contact(struct message *);
103 static int      ipsec_contacted(struct message *);
104 static int      ipsec_debug_attribute(u_int16_t, u_int8_t *, u_int16_t,
105     void *);
106 static void     ipsec_delete_spi(struct sa *, struct proto *, int);
107 static int16_t *ipsec_exchange_script(u_int8_t);
108 static void     ipsec_finalize_exchange(struct message *);
109 static void     ipsec_free_exchange_data(void *);
110 static void     ipsec_free_proto_data(void *);
111 static void     ipsec_free_sa_data(void *);
112 static struct keystate *ipsec_get_keystate(struct message *);
113 static u_int8_t *ipsec_get_spi(size_t *, u_int8_t, struct message *);
114 static int	ipsec_handle_leftover_payload(struct message *, u_int8_t,
115     struct payload *);
116 static int      ipsec_informational_post_hook(struct message *);
117 static int      ipsec_informational_pre_hook(struct message *);
118 static int      ipsec_initiator(struct message *);
119 static void     ipsec_proto_init(struct proto *, char *);
120 static int      ipsec_responder(struct message *);
121 static void     ipsec_setup_situation(u_int8_t *);
122 static int      ipsec_set_network(u_int8_t *, u_int8_t *, struct ipsec_sa *);
123 static size_t   ipsec_situation_size(void);
124 static u_int8_t ipsec_spi_size(u_int8_t);
125 static int      ipsec_validate_attribute(u_int16_t, u_int8_t *, u_int16_t,
126     void *);
127 static int      ipsec_validate_exchange(u_int8_t);
128 static int	ipsec_validate_id_information(u_int8_t, u_int8_t *, u_int8_t *,
129     size_t, struct exchange *);
130 static int      ipsec_validate_key_information(u_int8_t *, size_t);
131 static int      ipsec_validate_notification(u_int16_t);
132 static int      ipsec_validate_proto(u_int8_t);
133 static int      ipsec_validate_situation(u_int8_t *, size_t *, size_t);
134 static int      ipsec_validate_transform_id(u_int8_t, u_int8_t);
135 static int      ipsec_sa_tag(struct exchange *, struct sa *, struct sa *);
136 
137 static struct doi ipsec_doi = {
138 	{0}, IPSEC_DOI_IPSEC,
139 	sizeof(struct ipsec_exch), sizeof(struct ipsec_sa),
140 	sizeof(struct ipsec_proto),
141 	ipsec_debug_attribute,
142 	ipsec_delete_spi,
143 	ipsec_exchange_script,
144 	ipsec_finalize_exchange,
145 	ipsec_free_exchange_data,
146 	ipsec_free_proto_data,
147 	ipsec_free_sa_data,
148 	ipsec_get_keystate,
149 	ipsec_get_spi,
150 	ipsec_handle_leftover_payload,
151 	ipsec_informational_post_hook,
152 	ipsec_informational_pre_hook,
153 	ipsec_is_attribute_incompatible,
154 	ipsec_proto_init,
155 	ipsec_setup_situation,
156 	ipsec_situation_size,
157 	ipsec_spi_size,
158 	ipsec_validate_attribute,
159 	ipsec_validate_exchange,
160 	ipsec_validate_id_information,
161 	ipsec_validate_key_information,
162 	ipsec_validate_notification,
163 	ipsec_validate_proto,
164 	ipsec_validate_situation,
165 	ipsec_validate_transform_id,
166 	ipsec_initiator,
167 	ipsec_responder,
168 	ipsec_decode_ids
169 };
170 
171 int16_t script_quick_mode[] = {
172 	ISAKMP_PAYLOAD_HASH,	/* Initiator -> responder.  */
173 	ISAKMP_PAYLOAD_SA,
174 	ISAKMP_PAYLOAD_NONCE,
175 	EXCHANGE_SCRIPT_SWITCH,
176 	ISAKMP_PAYLOAD_HASH,	/* Responder -> initiator.  */
177 	ISAKMP_PAYLOAD_SA,
178 	ISAKMP_PAYLOAD_NONCE,
179 	EXCHANGE_SCRIPT_SWITCH,
180 	ISAKMP_PAYLOAD_HASH,	/* Initiator -> responder.  */
181 	EXCHANGE_SCRIPT_END
182 };
183 
184 int16_t script_new_group_mode[] = {
185 	ISAKMP_PAYLOAD_HASH,	/* Initiator -> responder.  */
186 	ISAKMP_PAYLOAD_SA,
187 	EXCHANGE_SCRIPT_SWITCH,
188 	ISAKMP_PAYLOAD_HASH,	/* Responder -> initiator.  */
189 	ISAKMP_PAYLOAD_SA,
190 	EXCHANGE_SCRIPT_END
191 };
192 
193 struct dst_spi_proto_arg {
194 	struct sockaddr *dst;
195 	u_int32_t       spi;
196 	u_int8_t        proto;
197 };
198 
199 /*
200  * Check if SA matches what we are asking for through V_ARG.  It has to
201  * be a finished phase 2 SA.
202  * if "proto" arg is 0, match any proto
203  */
204 static int
205 ipsec_sa_check(struct sa *sa, void *v_arg)
206 {
207 	struct dst_spi_proto_arg *arg = v_arg;
208 	struct proto   *proto;
209 	struct sockaddr *dst, *src;
210 	int             incoming;
211 
212 	if (sa->phase != 2 || !(sa->flags & SA_FLAG_READY))
213 		return 0;
214 
215 	sa->transport->vtbl->get_dst(sa->transport, &dst);
216 	if (memcmp(sockaddr_addrdata(dst), sockaddr_addrdata(arg->dst),
217 	    sockaddr_addrlen(dst)) == 0)
218 		incoming = 0;
219 	else {
220 		sa->transport->vtbl->get_src(sa->transport, &src);
221 		if (memcmp(sockaddr_addrdata(src), sockaddr_addrdata(arg->dst),
222 		    sockaddr_addrlen(src)) == 0)
223 			incoming = 1;
224 		else
225 			return 0;
226 	}
227 
228 	for (proto = TAILQ_FIRST(&sa->protos); proto;
229 	    proto = TAILQ_NEXT(proto, link))
230 		if ((arg->proto == 0 || proto->proto == arg->proto) &&
231 		    memcmp(proto->spi[incoming], &arg->spi, sizeof arg->spi)
232 		    == 0)
233 			return 1;
234 	return 0;
235 }
236 
237 /* Find an SA with a "name" of DST, SPI & PROTO.  */
238 struct sa *
239 ipsec_sa_lookup(struct sockaddr *dst, u_int32_t spi, u_int8_t proto)
240 {
241 	struct dst_spi_proto_arg arg;
242 
243 	arg.dst = dst;
244 	arg.spi = spi;
245 	arg.proto = proto;
246 	return sa_find(ipsec_sa_check, &arg);
247 }
248 
249 /*
250  * Check if SA matches the flow of another SA in V_ARG.  It has to
251  * be a finished non-replaced phase 2 SA.
252  * XXX At some point other selectors will matter here too.
253  */
254 static int
255 ipsec_sa_check_flow(struct sa *sa, void *v_arg)
256 {
257 	struct sa      *sa2 = v_arg;
258 	struct ipsec_sa *isa = sa->data, *isa2 = sa2->data;
259 
260 	if (sa == sa2 || sa->phase != 2 ||
261 	    (sa->flags & (SA_FLAG_READY | SA_FLAG_REPLACED)) != SA_FLAG_READY)
262 		return 0;
263 
264 	if (isa->tproto != isa2->tproto || isa->sport != isa2->sport ||
265 	    isa->dport != isa2->dport)
266 		return 0;
267 
268 	return isa->src_net->sa_family == isa2->src_net->sa_family &&
269 	    memcmp(sockaddr_addrdata(isa->src_net),
270 	    sockaddr_addrdata(isa2->src_net),
271 	    sockaddr_addrlen(isa->src_net)) == 0 &&
272 	    memcmp(sockaddr_addrdata(isa->src_mask),
273 	    sockaddr_addrdata(isa2->src_mask),
274 	    sockaddr_addrlen(isa->src_mask)) == 0 &&
275 	    memcmp(sockaddr_addrdata(isa->dst_net),
276 	    sockaddr_addrdata(isa2->dst_net),
277 	    sockaddr_addrlen(isa->dst_net)) == 0 &&
278 	    memcmp(sockaddr_addrdata(isa->dst_mask),
279 	    sockaddr_addrdata(isa2->dst_mask),
280 	    sockaddr_addrlen(isa->dst_mask)) == 0;
281 }
282 
283 /*
284  * Construct a PF tag if specified in the configuration.
285  * It is possible to use variables to expand the tag:
286  * $id		The string representation of the remote ID
287  * $domain	The stripped domain part of the ID (for FQDN and UFQDN)
288  */
289 static int
290 ipsec_sa_tag(struct exchange *exchange, struct sa *sa, struct sa *isakmp_sa)
291 {
292 	char *format, *section;
293 	char *id_string = NULL, *domain = NULL;
294 	int error = -1;
295 	size_t len;
296 
297 	sa->tag = NULL;
298 
299 	if (exchange->name == NULL ||
300 	    (section = exchange->name) == NULL ||
301 	    (format = conf_get_str(section, "PF-Tag")) == NULL)
302 		return (0);	/* ignore if not present */
303 
304 	len = PF_TAG_NAME_SIZE;
305 	if ((sa->tag = calloc(1, len)) == NULL) {
306 		log_error("ipsec_sa_tag: calloc");
307 		goto fail;
308 	}
309 	if (strlcpy(sa->tag, format, len) >= len) {
310 		log_print("ipsec_sa_tag: tag too long");
311 		goto fail;
312 	}
313 	if (isakmp_sa->initiator)
314 		id_string = ipsec_id_string(isakmp_sa->id_r,
315 		    isakmp_sa->id_r_len);
316 	else
317 		id_string = ipsec_id_string(isakmp_sa->id_i,
318 		    isakmp_sa->id_i_len);
319 
320 	if (strstr(format, "$id") != NULL) {
321 		if (id_string == NULL) {
322 			log_print("ipsec_sa_tag: cannot get ID");
323 			goto fail;
324 		}
325 		if (expand_string(sa->tag, len, "$id", id_string) != 0) {
326 			log_print("ipsec_sa_tag: failed to expand tag");
327 			goto fail;
328 		}
329 	}
330 
331 	if (strstr(format, "$domain") != NULL) {
332 		if (id_string == NULL) {
333 			log_print("ipsec_sa_tag: cannot get ID");
334 			goto fail;
335 		}
336 		if (strncmp(id_string, "fqdn/", strlen("fqdn/")) == 0)
337 			domain = strchr(id_string, '.');
338 		else if (strncmp(id_string, "ufqdn/", strlen("ufqdn/")) == 0)
339 			domain = strchr(id_string, '@');
340 		if (domain == NULL || strlen(domain) < 2) {
341 			log_print("ipsec_sa_tag: no valid domain in ID %s",
342 			    id_string);
343 			goto fail;
344 		}
345 		domain++;
346 		if (expand_string(sa->tag, len, "$domain", domain) != 0) {
347 			log_print("ipsec_sa_tag: failed to expand tag");
348 			goto fail;
349 		}
350 	}
351 
352 	LOG_DBG((LOG_SA, 10, "ipsec_sa_tag: tag_len %ld tag \"%s\"",
353 	    strlen(sa->tag), sa->tag));
354 
355 	error = 0;
356  fail:
357 	free(id_string);
358 	if (error != 0) {
359 		free(sa->tag);
360 		sa->tag = NULL;
361 	}
362 
363 	return (error);
364 }
365 
366 /*
367  * Do IPsec DOI specific finalizations task for the exchange where MSG was
368  * the final message.
369  */
370 static void
371 ipsec_finalize_exchange(struct message *msg)
372 {
373 	struct sa      *isakmp_sa = msg->isakmp_sa;
374 	struct ipsec_sa *isa;
375 	struct exchange *exchange = msg->exchange;
376 	struct ipsec_exch *ie = exchange->data;
377 	struct sa      *sa = 0, *old_sa;
378 	struct proto   *proto, *last_proto = 0;
379 	char           *addr1, *addr2, *mask1, *mask2;
380 
381 	switch (exchange->phase) {
382 	case 1:
383 		switch (exchange->type) {
384 		case ISAKMP_EXCH_ID_PROT:
385 		case ISAKMP_EXCH_AGGRESSIVE:
386 			isa = isakmp_sa->data;
387 			isa->hash = ie->hash->type;
388 			isa->prf_type = ie->prf_type;
389 			isa->skeyid_len = ie->skeyid_len;
390 			isa->skeyid_d = ie->skeyid_d;
391 			isa->skeyid_a = ie->skeyid_a;
392 			/* Prevents early free of SKEYID_*.  */
393 			ie->skeyid_a = ie->skeyid_d = 0;
394 
395 			/*
396 			 * If a lifetime was negotiated setup the expiration
397 			 * timers.
398 			 */
399 			if (isakmp_sa->seconds)
400 				sa_setup_expirations(isakmp_sa);
401 
402 			if (isakmp_sa->flags & SA_FLAG_NAT_T_KEEPALIVE)
403 				nat_t_setup_keepalive(isakmp_sa);
404 			break;
405 		}
406 		break;
407 
408 	case 2:
409 		switch (exchange->type) {
410 		case IKE_EXCH_QUICK_MODE:
411 			/*
412 			 * Tell the application(s) about the SPIs and key
413 			 * material.
414 			 */
415 			for (sa = TAILQ_FIRST(&exchange->sa_list); sa;
416 			    sa = TAILQ_NEXT(sa, next)) {
417 				isa = sa->data;
418 
419 				if (exchange->initiator) {
420 					/*
421 					 * Initiator is source, responder is
422 					 * destination.
423 					 */
424 					if (ipsec_set_network(ie->id_ci,
425 					    ie->id_cr, isa)) {
426 						log_print(
427 						    "ipsec_finalize_exchange: "
428 						    "ipsec_set_network "
429 						    "failed");
430 						return;
431 					}
432 				} else {
433 					/*
434 					 * Responder is source, initiator is
435 					 * destination.
436 					 */
437 					if (ipsec_set_network(ie->id_cr,
438 					    ie->id_ci, isa)) {
439 						log_print(
440 						    "ipsec_finalize_exchange: "
441 						    "ipsec_set_network "
442 						    "failed");
443 						return;
444 					}
445 				}
446 
447 				if (ipsec_sa_tag(exchange, sa, isakmp_sa) == -1)
448 					return;
449 
450 				for (proto = TAILQ_FIRST(&sa->protos),
451 				    last_proto = 0; proto;
452 				    proto = TAILQ_NEXT(proto, link)) {
453 					if (pf_key_v2_set_spi(sa, proto,
454 					    0, isakmp_sa) ||
455 					    (last_proto &&
456 					    pf_key_v2_group_spis(sa,
457 						last_proto, proto, 0)) ||
458 					    pf_key_v2_set_spi(sa, proto,
459 						1, isakmp_sa) ||
460 					    (last_proto &&
461 						pf_key_v2_group_spis(sa,
462 						last_proto, proto, 1)))
463 						/*
464 						 * XXX Tear down this
465 						 * exchange.
466 						 */
467 						return;
468 					last_proto = proto;
469 				}
470 
471 				if (sockaddr2text(isa->src_net, &addr1, 0))
472 					addr1 = 0;
473 				if (sockaddr2text(isa->src_mask, &mask1, 0))
474 					mask1 = 0;
475 				if (sockaddr2text(isa->dst_net, &addr2, 0))
476 					addr2 = 0;
477 				if (sockaddr2text(isa->dst_mask, &mask2, 0))
478 					mask2 = 0;
479 
480 				LOG_DBG((LOG_EXCHANGE, 50,
481 				    "ipsec_finalize_exchange: src %s %s "
482 				    "dst %s %s tproto %u sport %u dport %u",
483 				    addr1 ? addr1 : "<??\?>",
484 				    mask1 ?  mask1 : "<??\?>",
485 				    addr2 ? addr2 : "<??\?>",
486 				    mask2 ? mask2 : "<??\?>",
487 				    isa->tproto, ntohs(isa->sport),
488 				    ntohs(isa->dport)));
489 
490 				free(addr1);
491 				free(mask1);
492 				free(addr2);
493 				free(mask2);
494 
495 				/*
496 				 * If this is not an SA acquired by the
497 				 * kernel, it needs to have a SPD entry
498 				 * (a.k.a. flow) set up.
499 				 */
500 				if (!(sa->flags & SA_FLAG_ONDEMAND ||
501 				    conf_get_str("General", "Acquire-Only") ||
502 				    acquire_only) &&
503 				    pf_key_v2_enable_sa(sa, isakmp_sa))
504 					/* XXX Tear down this exchange.  */
505 					return;
506 
507 				/*
508 				 * Mark elder SAs with the same flow
509 				 * information as replaced.
510 				 */
511 				while ((old_sa = sa_find(ipsec_sa_check_flow,
512 				    sa)) != 0)
513 					sa_mark_replaced(old_sa);
514 			}
515 			break;
516 		}
517 	}
518 }
519 
520 /* Set the client addresses in ISA from SRC_ID and DST_ID.  */
521 static int
522 ipsec_set_network(u_int8_t *src_id, u_int8_t *dst_id, struct ipsec_sa *isa)
523 {
524 	int	id;
525 	char *name, *nat = NULL;
526 	u_int8_t *nat_id = NULL;
527 	size_t nat_sz;
528 
529 	if ((name = connection_passive_lookup_by_ids(src_id, dst_id)))
530 		nat = conf_get_str(name, "NAT-ID");
531 
532 	if (nat) {
533 		if ((nat_id = ipsec_build_id(nat, &nat_sz))) {
534 			LOG_DBG((LOG_EXCHANGE, 50, "ipsec_set_network: SRC-NAT:"
535 			    " src: %s -> %s", name, nat));
536 			src_id = nat_id;
537 		} else
538 			log_print("ipsec_set_network: ipsec_build_id"
539 			    " failed for NAT-ID: %s", nat);
540 	}
541 
542 	/* Set source address/mask.  */
543 	id = GET_ISAKMP_ID_TYPE(src_id);
544 	switch (id) {
545 	case IPSEC_ID_IPV4_ADDR:
546 	case IPSEC_ID_IPV4_ADDR_SUBNET:
547 		isa->src_net = (struct sockaddr *)calloc(1,
548 		    sizeof(struct sockaddr_in));
549 		if (!isa->src_net)
550 			goto memfail;
551 		isa->src_net->sa_family = AF_INET;
552 		isa->src_net->sa_len = sizeof(struct sockaddr_in);
553 
554 		isa->src_mask = (struct sockaddr *)calloc(1,
555 		    sizeof(struct sockaddr_in));
556 		if (!isa->src_mask)
557 			goto memfail;
558 		isa->src_mask->sa_family = AF_INET;
559 		isa->src_mask->sa_len = sizeof(struct sockaddr_in);
560 		break;
561 
562 	case IPSEC_ID_IPV6_ADDR:
563 	case IPSEC_ID_IPV6_ADDR_SUBNET:
564 		isa->src_net = (struct sockaddr *)calloc(1,
565 		    sizeof(struct sockaddr_in6));
566 		if (!isa->src_net)
567 			goto memfail;
568 		isa->src_net->sa_family = AF_INET6;
569 		isa->src_net->sa_len = sizeof(struct sockaddr_in6);
570 
571 		isa->src_mask = (struct sockaddr *)calloc(1,
572 		    sizeof(struct sockaddr_in6));
573 		if (!isa->src_mask)
574 			goto memfail;
575 		isa->src_mask->sa_family = AF_INET6;
576 		isa->src_mask->sa_len = sizeof(struct sockaddr_in6);
577 		break;
578 
579 	case IPSEC_ID_IPV4_RANGE:
580 	case IPSEC_ID_IPV6_RANGE:
581 	case IPSEC_ID_DER_ASN1_DN:
582 	case IPSEC_ID_DER_ASN1_GN:
583 	case IPSEC_ID_FQDN:
584 	case IPSEC_ID_KEY_ID:
585 	default:
586 		log_print("ipsec_set_network: ID type %d (%s) not supported",
587 		    id, constant_name(ipsec_id_cst, id));
588 		return -1;
589 	}
590 
591 	/* Net */
592 	memcpy(sockaddr_addrdata(isa->src_net), src_id + ISAKMP_ID_DATA_OFF,
593 	    sockaddr_addrlen(isa->src_net));
594 
595 	/* Mask */
596 	switch (id) {
597 	case IPSEC_ID_IPV4_ADDR:
598 	case IPSEC_ID_IPV6_ADDR:
599 		memset(sockaddr_addrdata(isa->src_mask), 0xff,
600 		    sockaddr_addrlen(isa->src_mask));
601 		break;
602 	case IPSEC_ID_IPV4_ADDR_SUBNET:
603 	case IPSEC_ID_IPV6_ADDR_SUBNET:
604 		memcpy(sockaddr_addrdata(isa->src_mask), src_id +
605 		    ISAKMP_ID_DATA_OFF + sockaddr_addrlen(isa->src_net),
606 		    sockaddr_addrlen(isa->src_mask));
607 		break;
608 	}
609 
610 	memcpy(&isa->sport,
611 	    src_id + ISAKMP_ID_DOI_DATA_OFF + IPSEC_ID_PORT_OFF,
612 	    IPSEC_ID_PORT_LEN);
613 
614 	if (nat_id)
615 		free(nat_id);
616 
617 	/* Set destination address.  */
618 	id = GET_ISAKMP_ID_TYPE(dst_id);
619 	switch (id) {
620 	case IPSEC_ID_IPV4_ADDR:
621 	case IPSEC_ID_IPV4_ADDR_SUBNET:
622 		isa->dst_net = (struct sockaddr *)calloc(1,
623 		    sizeof(struct sockaddr_in));
624 		if (!isa->dst_net)
625 			goto memfail;
626 		isa->dst_net->sa_family = AF_INET;
627 		isa->dst_net->sa_len = sizeof(struct sockaddr_in);
628 
629 		isa->dst_mask = (struct sockaddr *)calloc(1,
630 		    sizeof(struct sockaddr_in));
631 		if (!isa->dst_mask)
632 			goto memfail;
633 		isa->dst_mask->sa_family = AF_INET;
634 		isa->dst_mask->sa_len = sizeof(struct sockaddr_in);
635 		break;
636 
637 	case IPSEC_ID_IPV6_ADDR:
638 	case IPSEC_ID_IPV6_ADDR_SUBNET:
639 		isa->dst_net = (struct sockaddr *)calloc(1,
640 		    sizeof(struct sockaddr_in6));
641 		if (!isa->dst_net)
642 			goto memfail;
643 		isa->dst_net->sa_family = AF_INET6;
644 		isa->dst_net->sa_len = sizeof(struct sockaddr_in6);
645 
646 		isa->dst_mask = (struct sockaddr *)calloc(1,
647 		    sizeof(struct sockaddr_in6));
648 		if (!isa->dst_mask)
649 			goto memfail;
650 		isa->dst_mask->sa_family = AF_INET6;
651 		isa->dst_mask->sa_len = sizeof(struct sockaddr_in6);
652 		break;
653 
654 	case IPSEC_ID_IPV4_RANGE:
655 	case IPSEC_ID_IPV6_RANGE:
656 	case IPSEC_ID_DER_ASN1_DN:
657 	case IPSEC_ID_DER_ASN1_GN:
658 	case IPSEC_ID_FQDN:
659 	case IPSEC_ID_KEY_ID:
660 	default:
661 		log_print("ipsec_set_network: ID type %d (%s) not supported",
662 		    id, constant_name(ipsec_id_cst, id));
663 		return -1;
664 	}
665 
666 	/* Net */
667 	memcpy(sockaddr_addrdata(isa->dst_net), dst_id + ISAKMP_ID_DATA_OFF,
668 	    sockaddr_addrlen(isa->dst_net));
669 
670 	/* Mask */
671 	switch (id) {
672 	case IPSEC_ID_IPV4_ADDR:
673 	case IPSEC_ID_IPV6_ADDR:
674 		memset(sockaddr_addrdata(isa->dst_mask), 0xff,
675 		    sockaddr_addrlen(isa->dst_mask));
676 		break;
677 	case IPSEC_ID_IPV4_ADDR_SUBNET:
678 	case IPSEC_ID_IPV6_ADDR_SUBNET:
679 		memcpy(sockaddr_addrdata(isa->dst_mask), dst_id +
680 		    ISAKMP_ID_DATA_OFF + sockaddr_addrlen(isa->dst_net),
681 		    sockaddr_addrlen(isa->dst_mask));
682 		break;
683 	}
684 
685 	memcpy(&isa->tproto, dst_id + ISAKMP_ID_DOI_DATA_OFF +
686 	    IPSEC_ID_PROTO_OFF, IPSEC_ID_PROTO_LEN);
687 	memcpy(&isa->dport,
688 	    dst_id + ISAKMP_ID_DOI_DATA_OFF + IPSEC_ID_PORT_OFF,
689 	    IPSEC_ID_PORT_LEN);
690 	return 0;
691 
692 memfail:
693 	log_error("ipsec_set_network: calloc () failed");
694 	return -1;
695 }
696 
697 /* Free the DOI-specific exchange data pointed to by VIE.  */
698 static void
699 ipsec_free_exchange_data(void *vie)
700 {
701 	struct ipsec_exch *ie = vie;
702 	struct isakmp_cfg_attr *attr;
703 
704 	free(ie->sa_i_b);
705 	free(ie->id_ci);
706 	free(ie->id_cr);
707 	free(ie->g_xi);
708 	free(ie->g_xr);
709 	free(ie->g_xy);
710 	free(ie->skeyid);
711 	free(ie->skeyid_d);
712 	free(ie->skeyid_a);
713 	free(ie->skeyid_e);
714 	free(ie->hash_i);
715 	free(ie->hash_r);
716 	if (ie->group)
717 		group_free(ie->group);
718 	for (attr = LIST_FIRST(&ie->attrs); attr;
719 	    attr = LIST_FIRST(&ie->attrs)) {
720 		LIST_REMOVE(attr, link);
721 		if (attr->length)
722 			free(attr->value);
723 		free(attr);
724 	}
725 }
726 
727 /* Free the DOI-specific SA data pointed to by VISA.  */
728 static void
729 ipsec_free_sa_data(void *visa)
730 {
731 	struct ipsec_sa *isa = visa;
732 
733 	free(isa->src_net);
734 	free(isa->src_mask);
735 	free(isa->dst_net);
736 	free(isa->dst_mask);
737 	free(isa->skeyid_a);
738 	free(isa->skeyid_d);
739 }
740 
741 /* Free the DOI-specific protocol data of an SA pointed to by VIPROTO.  */
742 static void
743 ipsec_free_proto_data(void *viproto)
744 {
745 	struct ipsec_proto *iproto = viproto;
746 	int             i;
747 
748 	for (i = 0; i < 2; i++)
749 		free(iproto->keymat[i]);
750 }
751 
752 /* Return exchange script based on TYPE.  */
753 static int16_t *
754 ipsec_exchange_script(u_int8_t type)
755 {
756 	switch (type) {
757 	case ISAKMP_EXCH_TRANSACTION:
758 		return script_transaction;
759 	case IKE_EXCH_QUICK_MODE:
760 		return script_quick_mode;
761 	case IKE_EXCH_NEW_GROUP_MODE:
762 		return script_new_group_mode;
763 	}
764 	return 0;
765 }
766 
767 /* Initialize this DOI, requires doi_init to already have been called.  */
768 void
769 ipsec_init(void)
770 {
771 	doi_register(&ipsec_doi);
772 }
773 
774 /* Given a message MSG, return a suitable IV (or rather keystate).  */
775 static struct keystate *
776 ipsec_get_keystate(struct message *msg)
777 {
778 	struct keystate *ks;
779 	struct hash    *hash;
780 
781 	/* If we have already have an IV, use it.  */
782 	if (msg->exchange && msg->exchange->keystate) {
783 		ks = malloc(sizeof *ks);
784 		if (!ks) {
785 			log_error("ipsec_get_keystate: malloc (%lu) failed",
786 			    (unsigned long) sizeof *ks);
787 			return 0;
788 		}
789 		memcpy(ks, msg->exchange->keystate, sizeof *ks);
790 		return ks;
791 	}
792 	/*
793 	 * For phase 2 when no SA yet is setup we need to hash the IV used by
794 	 * the ISAKMP SA concatenated with the message ID, and use that as an
795 	 * IV for further cryptographic operations.
796          */
797 	if (!msg->isakmp_sa->keystate) {
798 		log_print("ipsec_get_keystate: no keystate in ISAKMP SA %p",
799 		    msg->isakmp_sa);
800 		return 0;
801 	}
802 	ks = crypto_clone_keystate(msg->isakmp_sa->keystate);
803 	if (!ks)
804 		return 0;
805 
806 	hash = hash_get(((struct ipsec_sa *)msg->isakmp_sa->data)->hash);
807 	hash->Init(hash->ctx);
808 	LOG_DBG_BUF((LOG_CRYPTO, 80, "ipsec_get_keystate: final phase 1 IV",
809 	    ks->riv, ks->xf->blocksize));
810 	hash->Update(hash->ctx, ks->riv, ks->xf->blocksize);
811 	LOG_DBG_BUF((LOG_CRYPTO, 80, "ipsec_get_keystate: message ID",
812 	    ((u_int8_t *) msg->iov[0].iov_base) + ISAKMP_HDR_MESSAGE_ID_OFF,
813 	    ISAKMP_HDR_MESSAGE_ID_LEN));
814 	hash->Update(hash->ctx, ((u_int8_t *) msg->iov[0].iov_base) +
815 	    ISAKMP_HDR_MESSAGE_ID_OFF, ISAKMP_HDR_MESSAGE_ID_LEN);
816 	hash->Final(hash->digest, hash->ctx);
817 	crypto_init_iv(ks, hash->digest, ks->xf->blocksize);
818 	LOG_DBG_BUF((LOG_CRYPTO, 80, "ipsec_get_keystate: phase 2 IV",
819 	    hash->digest, ks->xf->blocksize));
820 	return ks;
821 }
822 
823 static void
824 ipsec_setup_situation(u_int8_t *buf)
825 {
826 	SET_IPSEC_SIT_SIT(buf + ISAKMP_SA_SIT_OFF, IPSEC_SIT_IDENTITY_ONLY);
827 }
828 
829 static size_t
830 ipsec_situation_size(void)
831 {
832 	return IPSEC_SIT_SIT_LEN;
833 }
834 
835 static u_int8_t
836 ipsec_spi_size(u_int8_t proto)
837 {
838 	return IPSEC_SPI_SIZE;
839 }
840 
841 static int
842 ipsec_validate_attribute(u_int16_t type, u_int8_t * value, u_int16_t len,
843     void *vmsg)
844 {
845 	struct message *msg = vmsg;
846 
847 	if (msg->exchange->phase == 1 &&
848 	    (type < IKE_ATTR_ENCRYPTION_ALGORITHM || type > IKE_ATTR_GROUP_ORDER))
849 		return -1;
850 	if (msg->exchange->phase == 2 &&
851 	    (type < IPSEC_ATTR_SA_LIFE_TYPE || type > IPSEC_ATTR_ECN_TUNNEL))
852 		return -1;
853 	return 0;
854 }
855 
856 static int
857 ipsec_validate_exchange(u_int8_t exch)
858 {
859 	return exch != IKE_EXCH_QUICK_MODE && exch != IKE_EXCH_NEW_GROUP_MODE;
860 }
861 
862 static int
863 ipsec_validate_id_information(u_int8_t type, u_int8_t *extra, u_int8_t *buf,
864     size_t sz, struct exchange *exchange)
865 {
866 	u_int8_t        proto = GET_IPSEC_ID_PROTO(extra);
867 	u_int16_t       port = GET_IPSEC_ID_PORT(extra);
868 
869 	LOG_DBG((LOG_MESSAGE, 40,
870 	    "ipsec_validate_id_information: proto %d port %d type %d",
871 	    proto, port, type));
872 	if (type < IPSEC_ID_IPV4_ADDR || type > IPSEC_ID_KEY_ID)
873 		return -1;
874 
875 	switch (type) {
876 	case IPSEC_ID_IPV4_ADDR:
877 		LOG_DBG_BUF((LOG_MESSAGE, 40,
878 		    "ipsec_validate_id_information: IPv4", buf,
879 		    sizeof(struct in_addr)));
880 		break;
881 
882 	case IPSEC_ID_IPV6_ADDR:
883 		LOG_DBG_BUF((LOG_MESSAGE, 40,
884 		    "ipsec_validate_id_information: IPv6", buf,
885 		    sizeof(struct in6_addr)));
886 		break;
887 
888 	case IPSEC_ID_IPV4_ADDR_SUBNET:
889 		LOG_DBG_BUF((LOG_MESSAGE, 40,
890 		    "ipsec_validate_id_information: IPv4 network/netmask",
891 		    buf, 2 * sizeof(struct in_addr)));
892 		break;
893 
894 	case IPSEC_ID_IPV6_ADDR_SUBNET:
895 		LOG_DBG_BUF((LOG_MESSAGE, 40,
896 		    "ipsec_validate_id_information: IPv6 network/netmask",
897 		    buf, 2 * sizeof(struct in6_addr)));
898 		break;
899 
900 	default:
901 		break;
902 	}
903 
904 	if (exchange->phase == 1 &&
905 	    (proto != IPPROTO_UDP || port != UDP_DEFAULT_PORT) &&
906 	    (proto != 0 || port != 0)) {
907 		/*
908 		 * XXX SSH's ISAKMP tester fails this test (proto 17 - port
909 		 * 0).
910 		 */
911 #ifdef notyet
912 		return -1;
913 #else
914 		log_print("ipsec_validate_id_information: dubious ID "
915 		    "information accepted");
916 #endif
917 	}
918 	/* XXX More checks?  */
919 
920 	return 0;
921 }
922 
923 static int
924 ipsec_validate_key_information(u_int8_t *buf, size_t sz)
925 {
926 	/* XXX Not implemented yet.  */
927 	return 0;
928 }
929 
930 static int
931 ipsec_validate_notification(u_int16_t type)
932 {
933 	return type < IPSEC_NOTIFY_RESPONDER_LIFETIME ||
934 	    type > IPSEC_NOTIFY_INITIAL_CONTACT ? -1 : 0;
935 }
936 
937 static int
938 ipsec_validate_proto(u_int8_t proto)
939 {
940 	return proto < IPSEC_PROTO_IPSEC_AH ||
941 	    proto > IPSEC_PROTO_IPCOMP ? -1 : 0;
942 }
943 
944 static int
945 ipsec_validate_situation(u_int8_t *buf, size_t *sz, size_t len)
946 {
947 	if (len < IPSEC_SIT_SIT_OFF + IPSEC_SIT_SIT_LEN) {
948 		log_print("ipsec_validate_situation: payload too short: %u",
949 		    (unsigned int) len);
950 		return -1;
951 	}
952 	/* Currently only "identity only" situations are supported.  */
953 	if (GET_IPSEC_SIT_SIT(buf) != IPSEC_SIT_IDENTITY_ONLY)
954 		return 1;
955 
956 	*sz = IPSEC_SIT_SIT_LEN;
957 
958 	return 0;
959 }
960 
961 static int
962 ipsec_validate_transform_id(u_int8_t proto, u_int8_t transform_id)
963 {
964 	switch (proto) {
965 	/*
966 	 * As no unexpected protocols can occur, we just tie the
967 	 * default case to the first case, in order to silence a GCC
968 	 * warning.
969 	 */
970 	default:
971 	case ISAKMP_PROTO_ISAKMP:
972 		return transform_id != IPSEC_TRANSFORM_KEY_IKE;
973 	case IPSEC_PROTO_IPSEC_AH:
974 		return transform_id < IPSEC_AH_MD5 ||
975 		    transform_id > IPSEC_AH_RIPEMD ? -1 : 0;
976 	case IPSEC_PROTO_IPSEC_ESP:
977 		return transform_id < IPSEC_ESP_DES_IV64 ||
978 		    (transform_id > IPSEC_ESP_AES_GMAC &&
979 		    transform_id < IPSEC_ESP_AES_MARS) ||
980 		    transform_id > IPSEC_ESP_AES_TWOFISH ? -1 : 0;
981 	case IPSEC_PROTO_IPCOMP:
982 		return transform_id < IPSEC_IPCOMP_OUI ||
983 		    transform_id > IPSEC_IPCOMP_V42BIS ? -1 : 0;
984 	}
985 }
986 
987 static int
988 ipsec_initiator(struct message *msg)
989 {
990 	struct exchange *exchange = msg->exchange;
991 	int             (**script)(struct message *) = 0;
992 
993 	/* Check that the SA is coherent with the IKE rules.  */
994 	if (exchange->type != ISAKMP_EXCH_TRANSACTION &&
995 	    ((exchange->phase == 1 && exchange->type != ISAKMP_EXCH_ID_PROT &&
996 	    exchange->type != ISAKMP_EXCH_AGGRESSIVE &&
997 	    exchange->type != ISAKMP_EXCH_INFO) ||
998 	    (exchange->phase == 2 && exchange->type != IKE_EXCH_QUICK_MODE &&
999 	    exchange->type != ISAKMP_EXCH_INFO))) {
1000 		log_print("ipsec_initiator: unsupported exchange type %d "
1001 		    "in phase %d", exchange->type, exchange->phase);
1002 		return -1;
1003 	}
1004 	switch (exchange->type) {
1005 	case ISAKMP_EXCH_ID_PROT:
1006 		script = ike_main_mode_initiator;
1007 		break;
1008 	case ISAKMP_EXCH_AGGRESSIVE:
1009 		script = ike_aggressive_initiator;
1010 		break;
1011 	case ISAKMP_EXCH_TRANSACTION:
1012 		script = isakmp_cfg_initiator;
1013 		break;
1014 	case ISAKMP_EXCH_INFO:
1015 		return message_send_info(msg);
1016 	case IKE_EXCH_QUICK_MODE:
1017 		script = ike_quick_mode_initiator;
1018 		break;
1019 	default:
1020 		log_print("ipsec_initiator: unsupported exchange type %d",
1021 			  exchange->type);
1022 		return -1;
1023 	}
1024 
1025 	/* Run the script code for this step.  */
1026 	if (script)
1027 		return script[exchange->step] (msg);
1028 
1029 	return 0;
1030 }
1031 
1032 /*
1033  * delete all SA's from addr with the associated proto and SPI's
1034  *
1035  * spis[] is an array of SPIs of size 16-octet for proto ISAKMP
1036  * or 4-octet otherwise.
1037  */
1038 static void
1039 ipsec_delete_spi_list(struct sockaddr *addr, u_int8_t proto, u_int8_t *spis,
1040     int nspis, char *type)
1041 {
1042 	struct sa	*sa;
1043 	char		*peer;
1044 	char		 ids[1024];
1045 	int		 i;
1046 
1047 	for (i = 0; i < nspis; i++) {
1048 		if (proto == ISAKMP_PROTO_ISAKMP) {
1049 			u_int8_t *spi = spis + i * ISAKMP_HDR_COOKIES_LEN;
1050 
1051 			/*
1052 			 * This really shouldn't happen in IPSEC DOI
1053 			 * code, but Cisco VPN 3000 sends ISAKMP DELETE's
1054 			 * this way.
1055 			 */
1056 			sa = sa_lookup_isakmp_sa(addr, spi);
1057 		} else {
1058 			u_int32_t spi = ((u_int32_t *)spis)[i];
1059 
1060 			sa = ipsec_sa_lookup(addr, spi, proto);
1061 		}
1062 
1063 		if (sa == NULL) {
1064 			LOG_DBG((LOG_SA, 30, "ipsec_delete_spi_list: could "
1065 			    "not locate SA (SPI %08x, proto %u)",
1066 			    ((u_int32_t *)spis)[i], proto));
1067 			continue;
1068 		}
1069 
1070 		strlcpy(ids,
1071 		    sa->doi->decode_ids("initiator id: %s, responder id: %s",
1072 		    sa->id_i, sa->id_i_len, sa->id_r, sa->id_r_len, 0),
1073 		    sizeof ids);
1074 		if (sockaddr2text(addr, &peer, 0))
1075 			peer = NULL;
1076 
1077 		/* only log deletion of SAs which are not soft expired yet */
1078 		if (sa->soft_death != NULL)
1079 			log_verbose("isakmpd: Peer %s made us delete live SA "
1080 			    "%s for proto %d, %s", peer ? peer : "<unknown>",
1081 			    sa->name ? sa->name : "<unnamed>", proto, ids);
1082 
1083 		LOG_DBG((LOG_SA, 30, "ipsec_delete_spi_list: "
1084 		    "%s made us delete SA %p (%d references) for proto %d (%s)",
1085 		    type, sa, sa->refcnt, proto, ids));
1086 		free(peer);
1087 
1088 		/* Delete the SA and search for the next */
1089 		sa_free(sa);
1090 	}
1091 }
1092 
1093 static int
1094 ipsec_responder(struct message *msg)
1095 {
1096 	struct exchange *exchange = msg->exchange;
1097 	int             (**script)(struct message *) = 0;
1098 	struct payload *p;
1099 	u_int16_t       type;
1100 
1101 	/* Check that a new exchange is coherent with the IKE rules.  */
1102 	if (exchange->step == 0 && exchange->type != ISAKMP_EXCH_TRANSACTION &&
1103 	    ((exchange->phase == 1 && exchange->type != ISAKMP_EXCH_ID_PROT &&
1104 	    exchange->type != ISAKMP_EXCH_AGGRESSIVE &&
1105 	    exchange->type != ISAKMP_EXCH_INFO) ||
1106 	    (exchange->phase == 2 && exchange->type != IKE_EXCH_QUICK_MODE &&
1107 	    exchange->type != ISAKMP_EXCH_INFO))) {
1108 		message_drop(msg, ISAKMP_NOTIFY_UNSUPPORTED_EXCHANGE_TYPE,
1109 		    0, 1, 0);
1110 		return -1;
1111 	}
1112 	LOG_DBG((LOG_MISC, 30, "ipsec_responder: phase %d exchange %d step %d",
1113 	    exchange->phase, exchange->type, exchange->step));
1114 	switch (exchange->type) {
1115 	case ISAKMP_EXCH_ID_PROT:
1116 		script = ike_main_mode_responder;
1117 		break;
1118 	case ISAKMP_EXCH_AGGRESSIVE:
1119 		script = ike_aggressive_responder;
1120 		break;
1121 	case ISAKMP_EXCH_TRANSACTION:
1122 		script = isakmp_cfg_responder;
1123 		break;
1124 	case ISAKMP_EXCH_INFO:
1125 		TAILQ_FOREACH(p, &msg->payload[ISAKMP_PAYLOAD_NOTIFY], link) {
1126 			type = GET_ISAKMP_NOTIFY_MSG_TYPE(p->p);
1127 			LOG_DBG((LOG_EXCHANGE, 10,
1128 			    "ipsec_responder: got NOTIFY of type %s",
1129 			    constant_name(isakmp_notify_cst, type)));
1130 
1131 			switch (type) {
1132 			case IPSEC_NOTIFY_INITIAL_CONTACT:
1133 				/* Handled by leftover logic. */
1134 				break;
1135 
1136 			case ISAKMP_NOTIFY_STATUS_DPD_R_U_THERE:
1137 			case ISAKMP_NOTIFY_STATUS_DPD_R_U_THERE_ACK:
1138 				dpd_handle_notify(msg, p);
1139 				break;
1140 
1141 			default:
1142 				p->flags |= PL_MARK;
1143 				break;
1144 			}
1145 		}
1146 
1147 		/*
1148 		 * If any DELETEs are in here, let the logic of leftover
1149 		 * payloads deal with them.
1150 		 */
1151 		return 0;
1152 
1153 	case IKE_EXCH_QUICK_MODE:
1154 		script = ike_quick_mode_responder;
1155 		break;
1156 
1157 	default:
1158 		message_drop(msg, ISAKMP_NOTIFY_UNSUPPORTED_EXCHANGE_TYPE,
1159 		    0, 1, 0);
1160 		return -1;
1161 	}
1162 
1163 	/* Run the script code for this step.  */
1164 	if (script)
1165 		return script[exchange->step] (msg);
1166 
1167 	/*
1168 	 * XXX So far we don't accept any proposals for exchanges we don't
1169 	 * support.
1170          */
1171 	if (payload_first(msg, ISAKMP_PAYLOAD_SA)) {
1172 		message_drop(msg, ISAKMP_NOTIFY_NO_PROPOSAL_CHOSEN, 0, 1, 0);
1173 		return -1;
1174 	}
1175 	return 0;
1176 }
1177 
1178 static enum hashes
1179 from_ike_hash(u_int16_t hash)
1180 {
1181 	switch (hash) {
1182 		case IKE_HASH_MD5:
1183 		return HASH_MD5;
1184 	case IKE_HASH_SHA:
1185 		return HASH_SHA1;
1186 	case IKE_HASH_SHA2_256:
1187 		return HASH_SHA2_256;
1188 	case IKE_HASH_SHA2_384:
1189 		return HASH_SHA2_384;
1190 	case IKE_HASH_SHA2_512:
1191 		return HASH_SHA2_512;
1192 	}
1193 	return -1;
1194 }
1195 
1196 static enum transform
1197 from_ike_crypto(u_int16_t crypto)
1198 {
1199 	/* Coincidentally this is the null operation :-)  */
1200 	return crypto;
1201 }
1202 
1203 /*
1204  * Find out whether the attribute of type TYPE with a LEN length value
1205  * pointed to by VALUE is incompatible with what we can handle.
1206  * VMSG is a pointer to the current message.
1207  */
1208 int
1209 ipsec_is_attribute_incompatible(u_int16_t type, u_int8_t *value, u_int16_t len,
1210     void *vmsg)
1211 {
1212 	struct message *msg = vmsg;
1213 	u_int16_t dv = decode_16(value);
1214 
1215 	if (msg->exchange->phase == 1) {
1216 		switch (type) {
1217 		case IKE_ATTR_ENCRYPTION_ALGORITHM:
1218 			return !crypto_get(from_ike_crypto(dv));
1219 		case IKE_ATTR_HASH_ALGORITHM:
1220 			return !hash_get(from_ike_hash(dv));
1221 		case IKE_ATTR_AUTHENTICATION_METHOD:
1222 			return !ike_auth_get(dv);
1223 		case IKE_ATTR_GROUP_DESCRIPTION:
1224 			return (dv < IKE_GROUP_DESC_MODP_768 ||
1225 			    dv > IKE_GROUP_DESC_MODP_1536) &&
1226 			    (dv < IKE_GROUP_DESC_MODP_2048 ||
1227 			    dv > IKE_GROUP_DESC_MODP_8192);
1228 		case IKE_ATTR_GROUP_TYPE:
1229 			return 1;
1230 		case IKE_ATTR_GROUP_PRIME:
1231 			return 1;
1232 		case IKE_ATTR_GROUP_GENERATOR_1:
1233 			return 1;
1234 		case IKE_ATTR_GROUP_GENERATOR_2:
1235 			return 1;
1236 		case IKE_ATTR_GROUP_CURVE_A:
1237 			return 1;
1238 		case IKE_ATTR_GROUP_CURVE_B:
1239 			return 1;
1240 		case IKE_ATTR_LIFE_TYPE:
1241 			return dv < IKE_DURATION_SECONDS ||
1242 			    dv > IKE_DURATION_KILOBYTES;
1243 		case IKE_ATTR_LIFE_DURATION:
1244 			return len != 2 && len != 4;
1245 		case IKE_ATTR_PRF:
1246 			return 1;
1247 		case IKE_ATTR_KEY_LENGTH:
1248 			/*
1249 			 * Our crypto routines only allows key-lengths which
1250 			 * are multiples of an octet.
1251 			 */
1252 			return dv % 8 != 0;
1253 		case IKE_ATTR_FIELD_SIZE:
1254 			return 1;
1255 		case IKE_ATTR_GROUP_ORDER:
1256 			return 1;
1257 		}
1258 	} else {
1259 		switch (type) {
1260 		case IPSEC_ATTR_SA_LIFE_TYPE:
1261 			return dv < IPSEC_DURATION_SECONDS ||
1262 			    dv > IPSEC_DURATION_KILOBYTES;
1263 		case IPSEC_ATTR_SA_LIFE_DURATION:
1264 			return len != 2 && len != 4;
1265 		case IPSEC_ATTR_GROUP_DESCRIPTION:
1266 			return (dv < IKE_GROUP_DESC_MODP_768 ||
1267 			    dv > IKE_GROUP_DESC_MODP_1536) &&
1268 			    (dv < IKE_GROUP_DESC_MODP_2048 ||
1269 			    IKE_GROUP_DESC_MODP_8192 < dv);
1270 		case IPSEC_ATTR_ENCAPSULATION_MODE:
1271 			return dv != IPSEC_ENCAP_TUNNEL &&
1272 			    dv != IPSEC_ENCAP_TRANSPORT &&
1273 			    dv != IPSEC_ENCAP_UDP_ENCAP_TUNNEL &&
1274 			    dv != IPSEC_ENCAP_UDP_ENCAP_TRANSPORT &&
1275 			    dv != IPSEC_ENCAP_UDP_ENCAP_TUNNEL_DRAFT &&
1276 			    dv != IPSEC_ENCAP_UDP_ENCAP_TRANSPORT_DRAFT;
1277 		case IPSEC_ATTR_AUTHENTICATION_ALGORITHM:
1278 			return dv < IPSEC_AUTH_HMAC_MD5 ||
1279 			    dv > IPSEC_AUTH_HMAC_RIPEMD;
1280 		case IPSEC_ATTR_KEY_LENGTH:
1281 			/*
1282 			 * XXX Blowfish needs '0'. Others appear to disregard
1283 			 * this attr?
1284 			 */
1285 			return 0;
1286 		case IPSEC_ATTR_KEY_ROUNDS:
1287 			return 1;
1288 		case IPSEC_ATTR_COMPRESS_DICTIONARY_SIZE:
1289 			return 1;
1290 		case IPSEC_ATTR_COMPRESS_PRIVATE_ALGORITHM:
1291 			return 1;
1292 		case IPSEC_ATTR_ECN_TUNNEL:
1293 			return 1;
1294 		}
1295 	}
1296 	/* XXX Silence gcc.  */
1297 	return 1;
1298 }
1299 
1300 /*
1301  * Log the attribute of TYPE with a LEN length value pointed to by VALUE
1302  * in human-readable form.  VMSG is a pointer to the current message.
1303  */
1304 int
1305 ipsec_debug_attribute(u_int16_t type, u_int8_t *value, u_int16_t len,
1306     void *vmsg)
1307 {
1308 	struct message *msg = vmsg;
1309 	char            val[20];
1310 
1311 	/* XXX Transient solution.  */
1312 	if (len == 2)
1313 		snprintf(val, sizeof val, "%d", decode_16(value));
1314 	else if (len == 4)
1315 		snprintf(val, sizeof val, "%d", decode_32(value));
1316 	else
1317 		snprintf(val, sizeof val, "unrepresentable");
1318 
1319 	LOG_DBG((LOG_MESSAGE, 50, "Attribute %s value %s",
1320 	    constant_name(msg->exchange->phase == 1 ? ike_attr_cst :
1321 	    ipsec_attr_cst, type), val));
1322 	return 0;
1323 }
1324 
1325 /*
1326  * Decode the attribute of type TYPE with a LEN length value pointed to by
1327  * VALUE.  VIDA is a pointer to a context structure where we can find the
1328  * current message, SA and protocol.
1329  */
1330 int
1331 ipsec_decode_attribute(u_int16_t type, u_int8_t *value, u_int16_t len,
1332     void *vida)
1333 {
1334 	struct ipsec_decode_arg *ida = vida;
1335 	struct message *msg = ida->msg;
1336 	struct sa      *sa = ida->sa;
1337 	struct ipsec_sa *isa = sa->data;
1338 	struct proto   *proto = ida->proto;
1339 	struct ipsec_proto *iproto = proto->data;
1340 	struct exchange *exchange = msg->exchange;
1341 	struct ipsec_exch *ie = exchange->data;
1342 	static int      lifetype = 0;
1343 
1344 	if (exchange->phase == 1) {
1345 		switch (type) {
1346 		case IKE_ATTR_ENCRYPTION_ALGORITHM:
1347 			/* XXX Errors possible?  */
1348 			exchange->crypto = crypto_get(from_ike_crypto(
1349 			    decode_16(value)));
1350 			break;
1351 		case IKE_ATTR_HASH_ALGORITHM:
1352 			/* XXX Errors possible?  */
1353 			ie->hash = hash_get(from_ike_hash(decode_16(value)));
1354 			break;
1355 		case IKE_ATTR_AUTHENTICATION_METHOD:
1356 			/* XXX Errors possible?  */
1357 			ie->ike_auth = ike_auth_get(decode_16(value));
1358 			break;
1359 		case IKE_ATTR_GROUP_DESCRIPTION:
1360 			isa->group_desc = decode_16(value);
1361 			break;
1362 		case IKE_ATTR_GROUP_TYPE:
1363 			break;
1364 		case IKE_ATTR_GROUP_PRIME:
1365 			break;
1366 		case IKE_ATTR_GROUP_GENERATOR_1:
1367 			break;
1368 		case IKE_ATTR_GROUP_GENERATOR_2:
1369 			break;
1370 		case IKE_ATTR_GROUP_CURVE_A:
1371 			break;
1372 		case IKE_ATTR_GROUP_CURVE_B:
1373 			break;
1374 		case IKE_ATTR_LIFE_TYPE:
1375 			lifetype = decode_16(value);
1376 			return 0;
1377 		case IKE_ATTR_LIFE_DURATION:
1378 			switch (lifetype) {
1379 			case IKE_DURATION_SECONDS:
1380 				switch (len) {
1381 				case 2:
1382 					sa->seconds = decode_16(value);
1383 					break;
1384 				case 4:
1385 					sa->seconds = decode_32(value);
1386 					break;
1387 				default:
1388 					log_print("ipsec_decode_attribute: "
1389 					    "unreasonable lifetime");
1390 				}
1391 				break;
1392 			case IKE_DURATION_KILOBYTES:
1393 				switch (len) {
1394 				case 2:
1395 					sa->kilobytes = decode_16(value);
1396 					break;
1397 				case 4:
1398 					sa->kilobytes = decode_32(value);
1399 					break;
1400 				default:
1401 					log_print("ipsec_decode_attribute: "
1402 					    "unreasonable lifetime");
1403 				}
1404 				break;
1405 			default:
1406 				log_print("ipsec_decode_attribute: unknown "
1407 				    "lifetime type");
1408 			}
1409 			break;
1410 		case IKE_ATTR_PRF:
1411 			break;
1412 		case IKE_ATTR_KEY_LENGTH:
1413 			exchange->key_length = decode_16(value) / 8;
1414 			break;
1415 		case IKE_ATTR_FIELD_SIZE:
1416 			break;
1417 		case IKE_ATTR_GROUP_ORDER:
1418 			break;
1419 		}
1420 	} else {
1421 		switch (type) {
1422 		case IPSEC_ATTR_SA_LIFE_TYPE:
1423 			lifetype = decode_16(value);
1424 			return 0;
1425 		case IPSEC_ATTR_SA_LIFE_DURATION:
1426 			switch (lifetype) {
1427 			case IPSEC_DURATION_SECONDS:
1428 				switch (len) {
1429 				case 2:
1430 					sa->seconds = decode_16(value);
1431 					break;
1432 				case 4:
1433 					sa->seconds = decode_32(value);
1434 					break;
1435 				default:
1436 					log_print("ipsec_decode_attribute: "
1437 					    "unreasonable lifetime");
1438 				}
1439 				break;
1440 			case IPSEC_DURATION_KILOBYTES:
1441 				switch (len) {
1442 				case 2:
1443 					sa->kilobytes = decode_16(value);
1444 					break;
1445 				case 4:
1446 					sa->kilobytes = decode_32(value);
1447 					break;
1448 				default:
1449 					log_print("ipsec_decode_attribute: "
1450 					    "unreasonable lifetime");
1451 				}
1452 				break;
1453 			default:
1454 				log_print("ipsec_decode_attribute: unknown "
1455 				    "lifetime type");
1456 			}
1457 			break;
1458 		case IPSEC_ATTR_GROUP_DESCRIPTION:
1459 			isa->group_desc = decode_16(value);
1460 			break;
1461 		case IPSEC_ATTR_ENCAPSULATION_MODE:
1462 			/*
1463 			 * XXX Multiple protocols must have same
1464 			 * encapsulation mode, no?
1465 			 */
1466 			iproto->encap_mode = decode_16(value);
1467 			break;
1468 		case IPSEC_ATTR_AUTHENTICATION_ALGORITHM:
1469 			iproto->auth = decode_16(value);
1470 			break;
1471 		case IPSEC_ATTR_KEY_LENGTH:
1472 			iproto->keylen = decode_16(value);
1473 			break;
1474 		case IPSEC_ATTR_KEY_ROUNDS:
1475 			iproto->keyrounds = decode_16(value);
1476 			break;
1477 		case IPSEC_ATTR_COMPRESS_DICTIONARY_SIZE:
1478 			break;
1479 		case IPSEC_ATTR_COMPRESS_PRIVATE_ALGORITHM:
1480 			break;
1481 		case IPSEC_ATTR_ECN_TUNNEL:
1482 			break;
1483 		}
1484 	}
1485 	lifetype = 0;
1486 	return 0;
1487 }
1488 
1489 /*
1490  * Walk over the attributes of the transform payload found in BUF, and
1491  * fill out the fields of the SA attached to MSG.  Also mark the SA as
1492  * processed.
1493  */
1494 void
1495 ipsec_decode_transform(struct message *msg, struct sa *sa, struct proto *proto,
1496     u_int8_t *buf)
1497 {
1498 	struct ipsec_exch *ie = msg->exchange->data;
1499 	struct ipsec_decode_arg ida;
1500 
1501 	LOG_DBG((LOG_MISC, 20, "ipsec_decode_transform: transform %d chosen",
1502 	    GET_ISAKMP_TRANSFORM_NO(buf)));
1503 
1504 	ida.msg = msg;
1505 	ida.sa = sa;
1506 	ida.proto = proto;
1507 
1508 	/* The default IKE lifetime is 8 hours.  */
1509 	if (sa->phase == 1)
1510 		sa->seconds = 28800;
1511 
1512 	/* Extract the attributes and stuff them into the SA.  */
1513 	attribute_map(buf + ISAKMP_TRANSFORM_SA_ATTRS_OFF,
1514 	    GET_ISAKMP_GEN_LENGTH(buf) - ISAKMP_TRANSFORM_SA_ATTRS_OFF,
1515 	    ipsec_decode_attribute, &ida);
1516 
1517 	/*
1518 	 * If no pseudo-random function was negotiated, it's HMAC.
1519 	 * XXX As PRF_HMAC currently is zero, this is a no-op.
1520          */
1521 	if (!ie->prf_type)
1522 		ie->prf_type = PRF_HMAC;
1523 }
1524 
1525 /*
1526  * Delete the IPsec SA represented by the INCOMING direction in protocol PROTO
1527  * of the IKE security association SA.
1528  */
1529 static void
1530 ipsec_delete_spi(struct sa *sa, struct proto *proto, int incoming)
1531 {
1532 	if (sa->phase == 1)
1533 		return;
1534 
1535 	/*
1536 	 * If the SA was not replaced and was not one acquired through the
1537 	 * kernel (ACQUIRE message), remove the flow associated with it.
1538 	 * We ignore any errors from the disabling of the flow.
1539 	 */
1540 	if (sa->flags & SA_FLAG_READY && !(sa->flags & SA_FLAG_ONDEMAND ||
1541 	    sa->flags & SA_FLAG_REPLACED || acquire_only ||
1542 	    conf_get_str("General", "Acquire-Only")))
1543 		pf_key_v2_disable_sa(sa, incoming);
1544 
1545 	/* XXX Error handling?  Is it interesting?  */
1546 	pf_key_v2_delete_spi(sa, proto, incoming);
1547 }
1548 
1549 /*
1550  * Store BUF into the g^x entry of the exchange that message MSG belongs to.
1551  * PEER is non-zero when the value is our peer's, and zero when it is ours.
1552  */
1553 static int
1554 ipsec_g_x(struct message *msg, int peer, u_int8_t *buf)
1555 {
1556 	struct exchange *exchange = msg->exchange;
1557 	struct ipsec_exch *ie = exchange->data;
1558 	u_int8_t      **g_x;
1559 	int             initiator = exchange->initiator ^ peer;
1560 	char            header[32];
1561 
1562 	g_x = initiator ? &ie->g_xi : &ie->g_xr;
1563 	*g_x = malloc(ie->g_x_len);
1564 	if (!*g_x) {
1565 		log_error("ipsec_g_x: malloc (%lu) failed",
1566 		    (unsigned long)ie->g_x_len);
1567 		return -1;
1568 	}
1569 	memcpy(*g_x, buf, ie->g_x_len);
1570 	snprintf(header, sizeof header, "ipsec_g_x: g^x%c",
1571 	    initiator ? 'i' : 'r');
1572 	LOG_DBG_BUF((LOG_MISC, 80, header, *g_x, ie->g_x_len));
1573 	return 0;
1574 }
1575 
1576 /* Generate our DH value.  */
1577 int
1578 ipsec_gen_g_x(struct message *msg)
1579 {
1580 	struct exchange *exchange = msg->exchange;
1581 	struct ipsec_exch *ie = exchange->data;
1582 	u_int8_t       *buf;
1583 
1584 	buf = malloc(ISAKMP_KE_SZ + ie->g_x_len);
1585 	if (!buf) {
1586 		log_error("ipsec_gen_g_x: malloc (%lu) failed",
1587 		    ISAKMP_KE_SZ + (unsigned long)ie->g_x_len);
1588 		return -1;
1589 	}
1590 	if (message_add_payload(msg, ISAKMP_PAYLOAD_KEY_EXCH, buf,
1591 	    ISAKMP_KE_SZ + ie->g_x_len, 1)) {
1592 		free(buf);
1593 		return -1;
1594 	}
1595 	if (dh_create_exchange(ie->group, buf + ISAKMP_KE_DATA_OFF)) {
1596 		log_print("ipsec_gen_g_x: dh_create_exchange failed");
1597 		free(buf);
1598 		return -1;
1599 	}
1600 	return ipsec_g_x(msg, 0, buf + ISAKMP_KE_DATA_OFF);
1601 }
1602 
1603 /* Save the peer's DH value.  */
1604 int
1605 ipsec_save_g_x(struct message *msg)
1606 {
1607 	struct exchange *exchange = msg->exchange;
1608 	struct ipsec_exch *ie = exchange->data;
1609 	struct payload *kep;
1610 
1611 	kep = payload_first(msg, ISAKMP_PAYLOAD_KEY_EXCH);
1612 	kep->flags |= PL_MARK;
1613 	ie->g_x_len = GET_ISAKMP_GEN_LENGTH(kep->p) - ISAKMP_KE_DATA_OFF;
1614 
1615 	/* Check that the given length matches the group's expectancy.  */
1616 	if (ie->g_x_len != (size_t) dh_getlen(ie->group)) {
1617 		/* XXX Is this a good notify type?  */
1618 		message_drop(msg, ISAKMP_NOTIFY_PAYLOAD_MALFORMED, 0, 1, 0);
1619 		return -1;
1620 	}
1621 	return ipsec_g_x(msg, 1, kep->p + ISAKMP_KE_DATA_OFF);
1622 }
1623 
1624 /*
1625  * Get a SPI for PROTO and the transport MSG passed over.  Store the
1626  * size where SZ points.  NB!  A zero return is OK if *SZ is zero.
1627  */
1628 static u_int8_t *
1629 ipsec_get_spi(size_t *sz, u_int8_t proto, struct message *msg)
1630 {
1631 	struct sockaddr *dst, *src;
1632 	struct transport *transport = msg->transport;
1633 
1634 	if (msg->exchange->phase == 1) {
1635 		*sz = 0;
1636 		return 0;
1637 	} else {
1638 		/* We are the destination in the SA we want a SPI for.  */
1639 		transport->vtbl->get_src(transport, &dst);
1640 		/* The peer is the source.  */
1641 		transport->vtbl->get_dst(transport, &src);
1642 		return pf_key_v2_get_spi(sz, proto, src, dst,
1643 		    msg->exchange->seq);
1644 	}
1645 }
1646 
1647 /*
1648  * We have gotten a payload PAYLOAD of type TYPE, which did not get handled
1649  * by the logic of the exchange MSG takes part in.  Now is the time to deal
1650  * with such a payload if we know how to, if we don't, return -1, otherwise
1651  * 0.
1652  */
1653 int
1654 ipsec_handle_leftover_payload(struct message *msg, u_int8_t type,
1655     struct payload *payload)
1656 {
1657 	u_int32_t       spisz, nspis;
1658 	struct sockaddr *dst;
1659 	int             reenter = 0;
1660 	u_int8_t       *spis, proto;
1661 	struct sa      *sa;
1662 
1663 	switch (type) {
1664 	case ISAKMP_PAYLOAD_DELETE:
1665 		proto = GET_ISAKMP_DELETE_PROTO(payload->p);
1666 		nspis = GET_ISAKMP_DELETE_NSPIS(payload->p);
1667 		spisz = GET_ISAKMP_DELETE_SPI_SZ(payload->p);
1668 
1669 		if (nspis == 0) {
1670 			LOG_DBG((LOG_SA, 60, "ipsec_handle_leftover_payload: "
1671 			    "message specified zero SPIs, ignoring"));
1672 			return -1;
1673 		}
1674 		/* verify proper SPI size */
1675 		if ((proto == ISAKMP_PROTO_ISAKMP &&
1676 		    spisz != ISAKMP_HDR_COOKIES_LEN) ||
1677 		    (proto != ISAKMP_PROTO_ISAKMP && spisz != sizeof(u_int32_t))) {
1678 			log_print("ipsec_handle_leftover_payload: invalid SPI "
1679 			    "size %d for proto %d in DELETE payload",
1680 			    spisz, proto);
1681 			return -1;
1682 		}
1683 		spis = (u_int8_t *) calloc(nspis, spisz);
1684 		if (!spis) {
1685 			log_error("ipsec_handle_leftover_payload: malloc "
1686 			    "(%d) failed", nspis * spisz);
1687 			return -1;
1688 		}
1689 		/* extract SPI and get dst address */
1690 		memcpy(spis, payload->p + ISAKMP_DELETE_SPI_OFF, nspis * spisz);
1691 		msg->transport->vtbl->get_dst(msg->transport, &dst);
1692 
1693 		ipsec_delete_spi_list(dst, proto, spis, nspis, "DELETE");
1694 
1695 		free(spis);
1696 		payload->flags |= PL_MARK;
1697 		return 0;
1698 
1699 	case ISAKMP_PAYLOAD_NOTIFY:
1700 		switch (GET_ISAKMP_NOTIFY_MSG_TYPE(payload->p)) {
1701 		case IPSEC_NOTIFY_INITIAL_CONTACT:
1702 			/*
1703 			 * Permit INITIAL-CONTACT if
1704 			 *   - this is not an AGGRESSIVE mode exchange
1705 			 *   - it is protected by an ISAKMP SA
1706 			 *
1707 			 * XXX Instead of the first condition above, we could
1708 			 * XXX permit this only for phase 2. In the last
1709 			 * XXX packet of main-mode, this payload, while
1710 			 * XXX encrypted, is not part of the hash digest.  As
1711 			 * XXX we currently send our own INITIAL-CONTACTs at
1712 			 * XXX this point, this too would need to be changed.
1713 			 */
1714 			if (msg->exchange->type == ISAKMP_EXCH_AGGRESSIVE) {
1715 				log_print("ipsec_handle_leftover_payload: got "
1716 				    "INITIAL-CONTACT in AGGRESSIVE mode");
1717 				return -1;
1718 			}
1719 			if ((msg->exchange->flags & EXCHANGE_FLAG_ENCRYPT)
1720 			    == 0) {
1721 				log_print("ipsec_handle_leftover_payload: got "
1722 				    "INITIAL-CONTACT without ISAKMP SA");
1723 				return -1;
1724 			}
1725 
1726 			if ((msg->flags & MSG_AUTHENTICATED) == 0) {
1727 				log_print("ipsec_handle_leftover_payload: "
1728 				    "got unauthenticated INITIAL-CONTACT");
1729 				return -1;
1730 			}
1731 			/*
1732 			 * Find out who is sending this and then delete every
1733 			 * SA that is ready.  Exchanges will timeout
1734 			 * themselves and then the non-ready SAs will
1735 			 * disappear too.
1736 			 */
1737 			msg->transport->vtbl->get_dst(msg->transport, &dst);
1738 			while ((sa = sa_lookup_by_peer(dst, SA_LEN(dst), 0)) != 0) {
1739 				/*
1740 				 * Don't delete the current SA -- we received
1741 				 * the notification over it, so it's obviously
1742 				 * still active. We temporarily need to remove
1743 				 * the SA from the list to avoid an endless
1744 				 * loop, but keep a reference so it won't
1745 				 * disappear meanwhile.
1746 				 */
1747 				if (sa == msg->isakmp_sa) {
1748 					sa_reference(sa);
1749 					sa_remove(sa);
1750 					reenter = 1;
1751 					continue;
1752 				}
1753 				LOG_DBG((LOG_SA, 30,
1754 				    "ipsec_handle_leftover_payload: "
1755 				    "INITIAL-CONTACT made us delete SA %p",
1756 				    sa));
1757 				sa_delete(sa, 0);
1758 			}
1759 
1760 			if (reenter) {
1761 				sa_enter(msg->isakmp_sa);
1762 				sa_release(msg->isakmp_sa);
1763 			}
1764 			payload->flags |= PL_MARK;
1765 			return 0;
1766 		}
1767 	}
1768 	return -1;
1769 }
1770 
1771 /* Return the encryption keylength in octets of the ESP protocol PROTO.  */
1772 int
1773 ipsec_esp_enckeylength(struct proto *proto)
1774 {
1775 	struct ipsec_proto *iproto = proto->data;
1776 
1777 	/* Compute the keylength to use.  */
1778 	switch (proto->id) {
1779 	case IPSEC_ESP_DES:
1780 	case IPSEC_ESP_DES_IV32:
1781 	case IPSEC_ESP_DES_IV64:
1782 		return 8;
1783 	case IPSEC_ESP_3DES:
1784 		return 24;
1785 	case IPSEC_ESP_CAST:
1786 		if (!iproto->keylen)
1787 			return 16;
1788 		return iproto->keylen / 8;
1789 	case IPSEC_ESP_AES_128_CTR:
1790 		return 20;
1791 	case IPSEC_ESP_AES_GCM_16:
1792 	case IPSEC_ESP_AES_GMAC:
1793 		if (!iproto->keylen)
1794 			return 20;
1795 		return iproto->keylen / 8 + 4;
1796 	case IPSEC_ESP_AES:
1797 		if (!iproto->keylen)
1798 			return 16;
1799 		/* FALLTHROUGH */
1800 	default:
1801 		return iproto->keylen / 8;
1802 	}
1803 }
1804 
1805 /* Return the authentication keylength in octets of the ESP protocol PROTO.  */
1806 int
1807 ipsec_esp_authkeylength(struct proto *proto)
1808 {
1809 	struct ipsec_proto *iproto = proto->data;
1810 
1811 	switch (iproto->auth) {
1812 	case IPSEC_AUTH_HMAC_MD5:
1813 		return 16;
1814 	case IPSEC_AUTH_HMAC_SHA:
1815 	case IPSEC_AUTH_HMAC_RIPEMD:
1816 		return 20;
1817 	case IPSEC_AUTH_HMAC_SHA2_256:
1818 		return 32;
1819 	case IPSEC_AUTH_HMAC_SHA2_384:
1820 		return 48;
1821 	case IPSEC_AUTH_HMAC_SHA2_512:
1822 		return 64;
1823 	default:
1824 		return 0;
1825 	}
1826 }
1827 
1828 /* Return the authentication keylength in octets of the AH protocol PROTO.  */
1829 int
1830 ipsec_ah_keylength(struct proto *proto)
1831 {
1832 	switch (proto->id) {
1833 		case IPSEC_AH_MD5:
1834 		return 16;
1835 	case IPSEC_AH_SHA:
1836 	case IPSEC_AH_RIPEMD:
1837 		return 20;
1838 	case IPSEC_AH_SHA2_256:
1839 		return 32;
1840 	case IPSEC_AH_SHA2_384:
1841 		return 48;
1842 	case IPSEC_AH_SHA2_512:
1843 		return 64;
1844 	default:
1845 		return -1;
1846 	}
1847 }
1848 
1849 /* Return the total keymaterial length of the protocol PROTO.  */
1850 int
1851 ipsec_keymat_length(struct proto *proto)
1852 {
1853 	switch (proto->proto) {
1854 		case IPSEC_PROTO_IPSEC_ESP:
1855 		return ipsec_esp_enckeylength(proto)
1856 		    + ipsec_esp_authkeylength(proto);
1857 	case IPSEC_PROTO_IPSEC_AH:
1858 		return ipsec_ah_keylength(proto);
1859 	default:
1860 		return -1;
1861 	}
1862 }
1863 
1864 /* Helper function for ipsec_get_id().  */
1865 static int
1866 ipsec_get_proto_port(char *section, u_int8_t *tproto, u_int16_t *port)
1867 {
1868 	struct protoent	*pe = NULL;
1869 	struct servent	*se;
1870 	char	*pstr;
1871 
1872 	pstr = conf_get_str(section, "Protocol");
1873 	if (!pstr) {
1874 		*tproto = 0;
1875 		return 0;
1876 	}
1877 	*tproto = (u_int8_t)atoi(pstr);
1878 	if (!*tproto) {
1879 		pe = getprotobyname(pstr);
1880 		if (pe)
1881 			*tproto = pe->p_proto;
1882 	}
1883 	if (!*tproto) {
1884 		log_print("ipsec_get_proto_port: protocol \"%s\" unknown",
1885 		    pstr);
1886 		return -1;
1887 	}
1888 
1889 	pstr = conf_get_str(section, "Port");
1890 	if (!pstr)
1891 		return 0;
1892 	*port = (u_int16_t)atoi(pstr);
1893 	if (!*port) {
1894 		se = getservbyname(pstr,
1895 		    pe ? pe->p_name : (pstr ? pstr : NULL));
1896 		if (se)
1897 			*port = ntohs(se->s_port);
1898 	}
1899 	if (!*port) {
1900 		log_print("ipsec_get_proto_port: port \"%s\" unknown",
1901 		    pstr);
1902 		return -1;
1903 	}
1904 	return 0;
1905 }
1906 
1907 /*
1908  * Out of a named section SECTION in the configuration file find out
1909  * the network address and mask as well as the ID type.  Put the info
1910  * in the areas pointed to by ADDR, MASK, TPROTO, PORT, and ID respectively.
1911  * Return 0 on success and -1 on failure.
1912  */
1913 int
1914 ipsec_get_id(char *section, int *id, struct sockaddr **addr,
1915     struct sockaddr **mask, u_int8_t *tproto, u_int16_t *port)
1916 {
1917 	char	*type, *address, *netmask;
1918 	sa_family_t	af = 0;
1919 
1920 	type = conf_get_str(section, "ID-type");
1921 	if (!type) {
1922 		log_print("ipsec_get_id: section %s has no \"ID-type\" tag",
1923 		    section);
1924 		return -1;
1925 	}
1926 	*id = constant_value(ipsec_id_cst, type);
1927 	switch (*id) {
1928 	case IPSEC_ID_IPV4_ADDR:
1929 	case IPSEC_ID_IPV4_ADDR_SUBNET:
1930 		af = AF_INET;
1931 		break;
1932 	case IPSEC_ID_IPV6_ADDR:
1933 	case IPSEC_ID_IPV6_ADDR_SUBNET:
1934 		af = AF_INET6;
1935 		break;
1936 	}
1937 	switch (*id) {
1938 	case IPSEC_ID_IPV4_ADDR:
1939 	case IPSEC_ID_IPV6_ADDR: {
1940 		int ret;
1941 
1942 		address = conf_get_str(section, "Address");
1943 		if (!address) {
1944 			log_print("ipsec_get_id: section %s has no "
1945 			    "\"Address\" tag", section);
1946 			return -1;
1947 		}
1948 		if (text2sockaddr(address, NULL, addr, af, 0)) {
1949 			log_print("ipsec_get_id: invalid address %s in "
1950 			    "section %s", address, section);
1951 			return -1;
1952 		}
1953 		ret = ipsec_get_proto_port(section, tproto, port);
1954 		if (ret < 0)
1955 			free(*addr);
1956 
1957 		return ret;
1958 	}
1959 
1960 #ifdef notyet
1961 	case IPSEC_ID_FQDN:
1962 		return -1;
1963 
1964 	case IPSEC_ID_USER_FQDN:
1965 		return -1;
1966 #endif
1967 
1968 	case IPSEC_ID_IPV4_ADDR_SUBNET:
1969 	case IPSEC_ID_IPV6_ADDR_SUBNET: {
1970 		int ret;
1971 
1972 		address = conf_get_str(section, "Network");
1973 		if (!address) {
1974 			log_print("ipsec_get_id: section %s has no "
1975 			    "\"Network\" tag", section);
1976 			return -1;
1977 		}
1978 		if (text2sockaddr(address, NULL, addr, af, 0)) {
1979 			log_print("ipsec_get_id: invalid section %s "
1980 			    "network %s", section, address);
1981 			return -1;
1982 		}
1983 		netmask = conf_get_str(section, "Netmask");
1984 		if (!netmask) {
1985 			log_print("ipsec_get_id: section %s has no "
1986 			    "\"Netmask\" tag", section);
1987 			free(*addr);
1988 			return -1;
1989 		}
1990 		if (text2sockaddr(netmask, NULL, mask, af, 1)) {
1991 			log_print("ipsec_get_id: invalid section %s "
1992 			    "network %s", section, netmask);
1993 			free(*addr);
1994 			return -1;
1995 		}
1996 		ret = ipsec_get_proto_port(section, tproto, port);
1997 		if (ret < 0) {
1998 			free(*mask);
1999 			free(*addr);
2000 		}
2001 		return ret;
2002 	}
2003 
2004 #ifdef notyet
2005 	case IPSEC_ID_IPV4_RANGE:
2006 		return -1;
2007 
2008 	case IPSEC_ID_IPV6_RANGE:
2009 		return -1;
2010 
2011 	case IPSEC_ID_DER_ASN1_DN:
2012 		return -1;
2013 
2014 	case IPSEC_ID_DER_ASN1_GN:
2015 		return -1;
2016 
2017 	case IPSEC_ID_KEY_ID:
2018 		return -1;
2019 #endif
2020 
2021 	default:
2022 		log_print("ipsec_get_id: unknown ID type \"%s\" in "
2023 		    "section %s", type, section);
2024 		return -1;
2025 	}
2026 
2027 	return 0;
2028 }
2029 
2030 /*
2031  * XXX I rather want this function to return a status code, and fail if
2032  * we cannot fit the information in the supplied buffer.
2033  */
2034 static void
2035 ipsec_decode_id(char *buf, size_t size, u_int8_t *id, size_t id_len,
2036     int isakmpform)
2037 {
2038 	int             id_type;
2039 	char           *addr = 0, *mask = 0;
2040 	u_int32_t      *idp;
2041 
2042 	if (id) {
2043 		if (!isakmpform) {
2044 			/*
2045 			 * Exchanges and SAs dont carry the IDs in ISAKMP
2046 			 * form.
2047 			 */
2048 			id -= ISAKMP_GEN_SZ;
2049 			id_len += ISAKMP_GEN_SZ;
2050 		}
2051 		id_type = GET_ISAKMP_ID_TYPE(id);
2052 		idp = (u_int32_t *) (id + ISAKMP_ID_DATA_OFF);
2053 		switch (id_type) {
2054 		case IPSEC_ID_IPV4_ADDR:
2055 			util_ntoa(&addr, AF_INET, id + ISAKMP_ID_DATA_OFF);
2056 			snprintf(buf, size, "%s", addr);
2057 			break;
2058 
2059 		case IPSEC_ID_IPV4_ADDR_SUBNET:
2060 			util_ntoa(&addr, AF_INET, id + ISAKMP_ID_DATA_OFF);
2061 			util_ntoa(&mask, AF_INET, id + ISAKMP_ID_DATA_OFF + 4);
2062 			snprintf(buf, size, "%s/%s", addr, mask);
2063 			break;
2064 
2065 		case IPSEC_ID_IPV6_ADDR:
2066 			util_ntoa(&addr, AF_INET6, id + ISAKMP_ID_DATA_OFF);
2067 			snprintf(buf, size, "%s", addr);
2068 			break;
2069 
2070 		case IPSEC_ID_IPV6_ADDR_SUBNET:
2071 			util_ntoa(&addr, AF_INET6, id + ISAKMP_ID_DATA_OFF);
2072 			util_ntoa(&mask, AF_INET6, id + ISAKMP_ID_DATA_OFF +
2073 			    sizeof(struct in6_addr));
2074 			snprintf(buf, size, "%s/%s", addr, mask);
2075 			break;
2076 
2077 		case IPSEC_ID_FQDN:
2078 		case IPSEC_ID_USER_FQDN:
2079 			/* String is not NUL terminated, be careful */
2080 			id_len -= ISAKMP_ID_DATA_OFF;
2081 			id_len = MIN(id_len, size - 1);
2082 			memcpy(buf, id + ISAKMP_ID_DATA_OFF, id_len);
2083 			buf[id_len] = '\0';
2084 			break;
2085 
2086 		case IPSEC_ID_DER_ASN1_DN:
2087 			addr = x509_DN_string(id + ISAKMP_ID_DATA_OFF,
2088 			    id_len - ISAKMP_ID_DATA_OFF);
2089 			if (!addr) {
2090 				snprintf(buf, size, "unparsable ASN1 DN ID");
2091 				return;
2092 			}
2093 			strlcpy(buf, addr, size);
2094 			break;
2095 
2096 		default:
2097 			snprintf(buf, size, "<id type unknown: %x>", id_type);
2098 			break;
2099 		}
2100 	} else
2101 		snprintf(buf, size, "<no ipsec id>");
2102 	free(addr);
2103 	free(mask);
2104 }
2105 
2106 char *
2107 ipsec_decode_ids(char *fmt, u_int8_t *id1, size_t id1_len, u_int8_t *id2,
2108     size_t id2_len, int isakmpform)
2109 {
2110 	static char     result[1024];
2111 	char            s_id1[256], s_id2[256];
2112 
2113 	ipsec_decode_id(s_id1, sizeof s_id1, id1, id1_len, isakmpform);
2114 	ipsec_decode_id(s_id2, sizeof s_id2, id2, id2_len, isakmpform);
2115 
2116 	snprintf(result, sizeof result, fmt, s_id1, s_id2);
2117 	return result;
2118 }
2119 
2120 /*
2121  * Out of a named section SECTION in the configuration file build an
2122  * ISAKMP ID payload.  Ths payload size should be stashed in SZ.
2123  * The caller is responsible for freeing the payload.
2124  */
2125 u_int8_t *
2126 ipsec_build_id(char *section, size_t *sz)
2127 {
2128 	struct sockaddr *addr, *mask;
2129 	u_int8_t       *p;
2130 	int             id, subnet = 0;
2131 	u_int8_t        tproto = 0;
2132 	u_int16_t       port = 0;
2133 
2134 	if (ipsec_get_id(section, &id, &addr, &mask, &tproto, &port))
2135 		return 0;
2136 
2137 	if (id == IPSEC_ID_IPV4_ADDR_SUBNET || id == IPSEC_ID_IPV6_ADDR_SUBNET)
2138 		subnet = 1;
2139 
2140 	*sz = ISAKMP_ID_SZ + sockaddr_addrlen(addr);
2141 	if (subnet)
2142 		*sz += sockaddr_addrlen(mask);
2143 
2144 	p = malloc(*sz);
2145 	if (!p) {
2146 		log_print("ipsec_build_id: malloc(%lu) failed",
2147 		    (unsigned long)*sz);
2148 		if (subnet)
2149 			free(mask);
2150 		free(addr);
2151 		return 0;
2152 	}
2153 	SET_ISAKMP_ID_TYPE(p, id);
2154 	SET_ISAKMP_ID_DOI_DATA(p, (unsigned char *)"\000\000\000");
2155 
2156 	memcpy(p + ISAKMP_ID_DATA_OFF, sockaddr_addrdata(addr),
2157 	    sockaddr_addrlen(addr));
2158 	if (subnet)
2159 		memcpy(p + ISAKMP_ID_DATA_OFF + sockaddr_addrlen(addr),
2160 		    sockaddr_addrdata(mask), sockaddr_addrlen(mask));
2161 
2162 	SET_IPSEC_ID_PROTO(p + ISAKMP_ID_DOI_DATA_OFF, tproto);
2163 	SET_IPSEC_ID_PORT(p + ISAKMP_ID_DOI_DATA_OFF, port);
2164 
2165 	if (subnet)
2166 		free(mask);
2167 	free(addr);
2168 	return p;
2169 }
2170 
2171 /*
2172  * copy an ISAKMPD id
2173  */
2174 int
2175 ipsec_clone_id(u_int8_t **did, size_t *did_len, u_int8_t *id, size_t id_len)
2176 {
2177 	free(*did);
2178 
2179 	if (!id_len || !id) {
2180 		*did = 0;
2181 		*did_len = 0;
2182 		return 0;
2183 	}
2184 	*did = malloc(id_len);
2185 	if (!*did) {
2186 		*did_len = 0;
2187 		log_error("ipsec_clone_id: malloc(%lu) failed",
2188 		    (unsigned long)id_len);
2189 		return -1;
2190 	}
2191 	*did_len = id_len;
2192 	memcpy(*did, id, id_len);
2193 
2194 	return 0;
2195 }
2196 
2197 /*
2198  * IPsec-specific PROTO initializations.  SECTION is only set if we are the
2199  * initiator thus only usable there.
2200  * XXX I want to fix this later.
2201  */
2202 void
2203 ipsec_proto_init(struct proto *proto, char *section)
2204 {
2205 	struct ipsec_proto *iproto = proto->data;
2206 
2207 	if (proto->sa->phase == 2)
2208 		iproto->replay_window = section ? conf_get_num(section,
2209 		    "ReplayWindow", DEFAULT_REPLAY_WINDOW) :
2210 		    DEFAULT_REPLAY_WINDOW;
2211 }
2212 
2213 /*
2214  * Add a notification payload of type INITIAL CONTACT to MSG if this is
2215  * the first contact we have made to our peer.
2216  */
2217 int
2218 ipsec_initial_contact(struct message *msg)
2219 {
2220 	u_int8_t *buf;
2221 
2222 	if (ipsec_contacted(msg))
2223 		return 0;
2224 
2225 	buf = malloc(ISAKMP_NOTIFY_SZ + ISAKMP_HDR_COOKIES_LEN);
2226 	if (!buf) {
2227 		log_error("ike_phase_1_initial_contact: malloc (%d) failed",
2228 		    ISAKMP_NOTIFY_SZ + ISAKMP_HDR_COOKIES_LEN);
2229 		return -1;
2230 	}
2231 	SET_ISAKMP_NOTIFY_DOI(buf, IPSEC_DOI_IPSEC);
2232 	SET_ISAKMP_NOTIFY_PROTO(buf, ISAKMP_PROTO_ISAKMP);
2233 	SET_ISAKMP_NOTIFY_SPI_SZ(buf, ISAKMP_HDR_COOKIES_LEN);
2234 	SET_ISAKMP_NOTIFY_MSG_TYPE(buf, IPSEC_NOTIFY_INITIAL_CONTACT);
2235 	memcpy(buf + ISAKMP_NOTIFY_SPI_OFF, msg->isakmp_sa->cookies,
2236 	    ISAKMP_HDR_COOKIES_LEN);
2237 	if (message_add_payload(msg, ISAKMP_PAYLOAD_NOTIFY, buf,
2238 	    ISAKMP_NOTIFY_SZ + ISAKMP_HDR_COOKIES_LEN, 1)) {
2239 		free(buf);
2240 		return -1;
2241 	}
2242 	return ipsec_add_contact(msg);
2243 }
2244 
2245 /*
2246  * Compare the two contacts pointed to by A and B.  Return negative if
2247  * *A < *B, 0 if they are equal, and positive if *A is the largest of them.
2248  */
2249 static int
2250 addr_cmp(const void *a, const void *b)
2251 {
2252 	const struct contact *x = a, *y = b;
2253 	int             minlen = MIN(x->len, y->len);
2254 	int             rv = memcmp(x->addr, y->addr, minlen);
2255 
2256 	return rv ? rv : (x->len - y->len);
2257 }
2258 
2259 /*
2260  * Add the peer that MSG is bound to as an address we don't want to send
2261  * INITIAL CONTACT too from now on.  Do not call this function with a
2262  * specific address duplicate times. We want fast lookup, speed of insertion
2263  * is unimportant, if this is to scale.
2264  */
2265 static int
2266 ipsec_add_contact(struct message *msg)
2267 {
2268 	struct contact *new_contacts;
2269 	struct sockaddr *dst, *addr;
2270 	int             cnt;
2271 
2272 	if (contact_cnt == contact_limit) {
2273 		cnt = contact_limit ? 2 * contact_limit : 64;
2274 		new_contacts = realloc(contacts, cnt * sizeof contacts[0]);
2275 		if (!new_contacts) {
2276 			log_error("ipsec_add_contact: "
2277 			    "realloc (%p, %lu) failed", contacts,
2278 			    cnt * (unsigned long) sizeof contacts[0]);
2279 			return -1;
2280 		}
2281 		contact_limit = cnt;
2282 		contacts = new_contacts;
2283 	}
2284 	msg->transport->vtbl->get_dst(msg->transport, &dst);
2285 	addr = malloc(SA_LEN(dst));
2286 	if (!addr) {
2287 		log_error("ipsec_add_contact: malloc (%lu) failed",
2288 		    (unsigned long)SA_LEN(dst));
2289 		return -1;
2290 	}
2291 	memcpy(addr, dst, SA_LEN(dst));
2292 	contacts[contact_cnt].addr = addr;
2293 	contacts[contact_cnt++].len = SA_LEN(dst);
2294 
2295 	/*
2296 	 * XXX There are better algorithms for already mostly-sorted data like
2297 	 * this, but only qsort is standard.  I will someday do this inline.
2298          */
2299 	qsort(contacts, contact_cnt, sizeof *contacts, addr_cmp);
2300 	return 0;
2301 }
2302 
2303 /* Return true if the recipient of MSG has already been contacted.  */
2304 static int
2305 ipsec_contacted(struct message *msg)
2306 {
2307 	struct contact  contact;
2308 
2309 	msg->transport->vtbl->get_dst(msg->transport, &contact.addr);
2310 	contact.len = SA_LEN(contact.addr);
2311 	return contacts ? (bsearch(&contact, contacts, contact_cnt,
2312 	    sizeof *contacts, addr_cmp) != 0) : 0;
2313 }
2314 
2315 /* Add a HASH for to MSG.  */
2316 u_int8_t *
2317 ipsec_add_hash_payload(struct message *msg, size_t hashsize)
2318 {
2319 	u_int8_t *buf;
2320 
2321 	buf = malloc(ISAKMP_HASH_SZ + hashsize);
2322 	if (!buf) {
2323 		log_error("ipsec_add_hash_payload: malloc (%lu) failed",
2324 		    ISAKMP_HASH_SZ + (unsigned long) hashsize);
2325 		return 0;
2326 	}
2327 	if (message_add_payload(msg, ISAKMP_PAYLOAD_HASH, buf,
2328 	    ISAKMP_HASH_SZ + hashsize, 1)) {
2329 		free(buf);
2330 		return 0;
2331 	}
2332 	return buf;
2333 }
2334 
2335 /* Fill in the HASH payload of MSG.  */
2336 int
2337 ipsec_fill_in_hash(struct message *msg)
2338 {
2339 	struct exchange *exchange = msg->exchange;
2340 	struct sa      *isakmp_sa = msg->isakmp_sa;
2341 	struct ipsec_sa *isa = isakmp_sa->data;
2342 	struct hash    *hash = hash_get(isa->hash);
2343 	struct prf     *prf;
2344 	struct payload *payload;
2345 	u_int8_t       *buf;
2346 	u_int32_t       i;
2347 	char            header[80];
2348 
2349 	/* If no SKEYID_a, we need not do anything.  */
2350 	if (!isa->skeyid_a)
2351 		return 0;
2352 
2353 	payload = payload_first(msg, ISAKMP_PAYLOAD_HASH);
2354 	if (!payload) {
2355 		log_print("ipsec_fill_in_hash: no HASH payload found");
2356 		return -1;
2357 	}
2358 	buf = payload->p;
2359 
2360 	/* Allocate the prf and start calculating our HASH(1).  */
2361 	LOG_DBG_BUF((LOG_MISC, 90, "ipsec_fill_in_hash: SKEYID_a",
2362 	    isa->skeyid_a, isa->skeyid_len));
2363 	prf = prf_alloc(isa->prf_type, hash->type, isa->skeyid_a,
2364 	    isa->skeyid_len);
2365 	if (!prf)
2366 		return -1;
2367 
2368 	prf->Init(prf->prfctx);
2369 	LOG_DBG_BUF((LOG_MISC, 90, "ipsec_fill_in_hash: message_id",
2370 	    exchange->message_id, ISAKMP_HDR_MESSAGE_ID_LEN));
2371 	prf->Update(prf->prfctx, exchange->message_id,
2372 	    ISAKMP_HDR_MESSAGE_ID_LEN);
2373 
2374 	/* Loop over all payloads after HASH(1).  */
2375 	for (i = 2; i < msg->iovlen; i++) {
2376 		/* XXX Misleading payload type printouts.  */
2377 		snprintf(header, sizeof header,
2378 		    "ipsec_fill_in_hash: payload %d after HASH(1)", i - 1);
2379 		LOG_DBG_BUF((LOG_MISC, 90, header, msg->iov[i].iov_base,
2380 		    msg->iov[i].iov_len));
2381 		prf->Update(prf->prfctx, msg->iov[i].iov_base,
2382 		    msg->iov[i].iov_len);
2383 	}
2384 	prf->Final(buf + ISAKMP_HASH_DATA_OFF, prf->prfctx);
2385 	prf_free(prf);
2386 	LOG_DBG_BUF((LOG_MISC, 80, "ipsec_fill_in_hash: HASH(1)", buf +
2387 	    ISAKMP_HASH_DATA_OFF, hash->hashsize));
2388 
2389 	return 0;
2390 }
2391 
2392 /* Add a HASH payload to MSG, if we have an ISAKMP SA we're protected by.  */
2393 static int
2394 ipsec_informational_pre_hook(struct message *msg)
2395 {
2396 	struct sa      *isakmp_sa = msg->isakmp_sa;
2397 	struct ipsec_sa *isa;
2398 	struct hash    *hash;
2399 
2400 	if (!isakmp_sa)
2401 		return 0;
2402 	isa = isakmp_sa->data;
2403 	hash = hash_get(isa->hash);
2404 	return ipsec_add_hash_payload(msg, hash->hashsize) == 0;
2405 }
2406 
2407 /*
2408  * Fill in the HASH payload in MSG, if we have an ISAKMP SA we're protected by.
2409  */
2410 static int
2411 ipsec_informational_post_hook(struct message *msg)
2412 {
2413 	if (!msg->isakmp_sa)
2414 		return 0;
2415 	return ipsec_fill_in_hash(msg);
2416 }
2417 
2418 ssize_t
2419 ipsec_id_size(char *section, u_int8_t *id)
2420 {
2421 	char *type, *data;
2422 
2423 	type = conf_get_str(section, "ID-type");
2424 	if (!type) {
2425 		log_print("ipsec_id_size: section %s has no \"ID-type\" tag",
2426 		    section);
2427 		return -1;
2428 	}
2429 	*id = constant_value(ipsec_id_cst, type);
2430 	switch (*id) {
2431 	case IPSEC_ID_IPV4_ADDR:
2432 		return sizeof(struct in_addr);
2433 	case IPSEC_ID_IPV4_ADDR_SUBNET:
2434 		return 2 * sizeof(struct in_addr);
2435 	case IPSEC_ID_IPV6_ADDR:
2436 		return sizeof(struct in6_addr);
2437 	case IPSEC_ID_IPV6_ADDR_SUBNET:
2438 		return 2 * sizeof(struct in6_addr);
2439 	case IPSEC_ID_FQDN:
2440 	case IPSEC_ID_USER_FQDN:
2441 	case IPSEC_ID_KEY_ID:
2442 	case IPSEC_ID_DER_ASN1_DN:
2443 	case IPSEC_ID_DER_ASN1_GN:
2444 		data = conf_get_str(section, "Name");
2445 		if (!data) {
2446 			log_print("ipsec_id_size: "
2447 			    "section %s has no \"Name\" tag", section);
2448 			return -1;
2449 		}
2450 		return strlen(data);
2451 	}
2452 	log_print("ipsec_id_size: unrecognized/unsupported ID-type %d (%s)",
2453 	    *id, type);
2454 	return -1;
2455 }
2456 
2457 /*
2458  * Generate a string version of the ID.
2459  */
2460 char *
2461 ipsec_id_string(u_int8_t *id, size_t id_len)
2462 {
2463 	char           *buf = 0;
2464 	char           *addrstr = 0;
2465 	size_t          len, size;
2466 
2467 	/*
2468 	 * XXX Real ugly way of making the offsets correct.  Be aware that id
2469 	 * now will point before the actual buffer and cannot be dereferenced
2470 	 * without an offset larger than or equal to ISAKM_GEN_SZ.
2471          */
2472 	id -= ISAKMP_GEN_SZ;
2473 
2474 	/* This is the actual length of the ID data field.  */
2475 	id_len += ISAKMP_GEN_SZ - ISAKMP_ID_DATA_OFF;
2476 
2477 	/*
2478 	 * Conservative allocation.
2479 	 * XXX I think the ASN1 DN case can be thought through to give a better
2480 	 * estimate.
2481          */
2482 	size = MAX(sizeof "ipv6/ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff",
2483 	    sizeof "asn1_dn/" + id_len);
2484 	buf = malloc(size);
2485 	if (!buf)
2486 		/* XXX Log?  */
2487 		goto fail;
2488 
2489 	switch (GET_ISAKMP_ID_TYPE(id)) {
2490 	case IPSEC_ID_IPV4_ADDR:
2491 		if (id_len < sizeof(struct in_addr))
2492 			goto fail;
2493 		util_ntoa(&addrstr, AF_INET, id + ISAKMP_ID_DATA_OFF);
2494 		if (!addrstr)
2495 			goto fail;
2496 		snprintf(buf, size, "ipv4/%s", addrstr);
2497 		break;
2498 
2499 	case IPSEC_ID_IPV6_ADDR:
2500 		if (id_len < sizeof(struct in6_addr))
2501 			goto fail;
2502 		util_ntoa(&addrstr, AF_INET6, id + ISAKMP_ID_DATA_OFF);
2503 		if (!addrstr)
2504 			goto fail;
2505 		snprintf(buf, size, "ipv6/%s", addrstr);
2506 		break;
2507 
2508 	case IPSEC_ID_FQDN:
2509 	case IPSEC_ID_USER_FQDN:
2510 		strlcpy(buf, GET_ISAKMP_ID_TYPE(id) == IPSEC_ID_FQDN ?
2511 		    "fqdn/" : "ufqdn/", size);
2512 		len = strlen(buf);
2513 
2514 		memcpy(buf + len, id + ISAKMP_ID_DATA_OFF, id_len);
2515 		*(buf + len + id_len) = '\0';
2516 		break;
2517 
2518 	case IPSEC_ID_DER_ASN1_DN:
2519 		strlcpy(buf, "asn1_dn/", size);
2520 		len = strlen(buf);
2521 		addrstr = x509_DN_string(id + ISAKMP_ID_DATA_OFF, id_len);
2522 		if (!addrstr)
2523 			goto fail;
2524 		if (size < len + strlen(addrstr) + 1)
2525 			goto fail;
2526 		strlcpy(buf + len, addrstr, size - len);
2527 		break;
2528 
2529 	default:
2530 		/* Unknown type.  */
2531 		LOG_DBG((LOG_MISC, 10,
2532 		    "ipsec_id_string: unknown identity type %d\n",
2533 		    GET_ISAKMP_ID_TYPE(id)));
2534 		goto fail;
2535 	}
2536 
2537 	free(addrstr);
2538 	return buf;
2539 
2540 fail:
2541 	free(buf);
2542 	free(addrstr);
2543 	return 0;
2544 }
2545