1/* $NetBSD: ipsec_output.c,v 1.41 2015/03/30 03:51:50 ozaki-r Exp $ */
2
3/*-
4 * Copyright (c) 2002, 2003 Sam Leffler, Errno Consulting
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 *
28 * $FreeBSD: /repoman/r/ncvs/src/sys/netipsec/ipsec_output.c,v 1.3.2.2 2003/03/28 20:32:53 sam Exp $
29 */
30
31#include <sys/cdefs.h>
32__KERNEL_RCSID(0, "$NetBSD: ipsec_output.c,v 1.41 2015/03/30 03:51:50 ozaki-r Exp $");
33
34/*
35 * IPsec output processing.
36 */
37#include "opt_inet.h"
38#ifdef __FreeBSD__
39#include "opt_inet6.h"
40#endif
41
42#include <sys/param.h>
43#include <sys/systm.h>
44#include <sys/mbuf.h>
45#include <sys/domain.h>
46#include <sys/protosw.h>
47#include <sys/socket.h>
48#include <sys/errno.h>
49#include <sys/syslog.h>
50
51#include <net/if.h>
52#include <net/route.h>
53
54#include <netinet/in.h>
55#include <netinet/in_systm.h>
56#include <netinet/ip.h>
57#include <netinet/ip_var.h>
58#include <netinet/in_var.h>
59#include <netinet/ip_ecn.h>
60#ifdef INET6
61# ifdef __FreeBSD__
62# include <netinet6/ip6_ecn.h>
63# endif
64#endif
65
66#include <netinet/ip6.h>
67#ifdef INET6
68#include <netinet6/ip6_var.h>
69#endif
70#include <netinet/in_pcb.h>
71#ifdef INET6
72#include <netinet/icmp6.h>
73#endif
74#include <netinet/udp.h>
75
76#include <netipsec/ipsec.h>
77#include <netipsec/ipsec_var.h>
78#include <netipsec/ipsec_private.h>
79#ifdef INET6
80#include <netipsec/ipsec6.h>
81#endif
82#include <netipsec/ah_var.h>
83#include <netipsec/esp_var.h>
84#include <netipsec/ipcomp_var.h>
85
86#include <netipsec/xform.h>
87
88#include <netipsec/key.h>
89#include <netipsec/keydb.h>
90#include <netipsec/key_debug.h>
91#include <netipsec/ipsec_osdep.h>
92
93#include <net/net_osdep.h> /* ovbcopy() in ipsec6_encapsulate() */
94
95
96/*
97 * Add a IPSEC_OUT_DONE tag to mark that we have finished the ipsec processing
98 * It will be used by ip{,6}_output to check if we have already or not
99 * processed this packet.
100 */
101static int
102ipsec_register_done(struct mbuf *m, int * error)
103{
104 struct m_tag *mtag;
105
106 mtag = m_tag_get(PACKET_TAG_IPSEC_OUT_DONE, 0, M_NOWAIT);
107 if (mtag == NULL) {
108 DPRINTF(("ipsec_register_done: could not get packet tag\n"));
109 *error = ENOMEM;
110 return -1;
111 }
112
113 m_tag_prepend(m, mtag);
114 return 0;
115}
116
117static int
118ipsec_reinject_ipstack(struct mbuf *m, int af)
119{
120#ifdef INET
121#ifdef __FreeBSD__
122 struct ip *ip;
123#endif /* __FreeBSD_ */
124#endif /* INET */
125#if defined(INET) || defined(INET6)
126 int rv;
127#endif
128
129 switch (af) {
130#ifdef INET
131 case AF_INET:
132#ifdef __FreeBSD__
133 ip = mtod(m, struct ip *);
134 /* FreeBSD ip_output() expects ip_len, ip_off in host endian */
135 ip->ip_len = ntohs(ip->ip_len);
136 ip->ip_off = ntohs(ip->ip_off);
137#endif /* __FreeBSD_ */
138 KERNEL_LOCK(1, NULL);
139 rv = ip_output(m, NULL, NULL, IP_RAWOUTPUT|IP_NOIPNEWID,
140 NULL, NULL);
141 KERNEL_UNLOCK_ONE(NULL);
142 return rv;
143
144#endif /* INET */
145#ifdef INET6
146 case AF_INET6:
147 /*
148 * We don't need massage, IPv6 header fields are always in
149 * net endian.
150 */
151 KERNEL_LOCK(1, NULL);
152 rv = ip6_output(m, NULL, NULL, 0, NULL, NULL, NULL);
153 KERNEL_UNLOCK_ONE(NULL);
154 return rv;
155#endif /* INET6 */
156 }
157
158 panic("ipsec_reinject_ipstack : iunknown protocol family %u\n", af);
159 return -1; /* NOTREACHED */
160}
161
162int
163ipsec_process_done(struct mbuf *m, struct ipsecrequest *isr)
164{
165 struct secasvar *sav;
166 struct secasindex *saidx;
167 int error;
168#ifdef INET
169 struct ip * ip;
170#endif /* INET */
171#ifdef INET6
172 struct ip6_hdr * ip6;
173#endif /* INET6 */
174 struct mbuf * mo;
175 struct udphdr *udp = NULL;
176 uint64_t * data = NULL;
177 int hlen, roff;
178
179 IPSEC_SPLASSERT_SOFTNET("ipsec_process_done");
180
181 IPSEC_ASSERT(m != NULL, ("ipsec_process_done: null mbuf"));
182 IPSEC_ASSERT(isr != NULL, ("ipsec_process_done: null ISR"));
183 sav = isr->sav;
184 IPSEC_ASSERT(sav != NULL, ("ipsec_process_done: null SA"));
185 IPSEC_ASSERT(sav->sah != NULL, ("ipsec_process_done: null SAH"));
186
187 saidx = &sav->sah->saidx;
188
189 if(sav->natt_type != 0) {
190 ip = mtod(m, struct ip *);
191
192 hlen = sizeof(struct udphdr);
193 if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE)
194 hlen += sizeof(uint64_t);
195
196 mo = m_makespace(m, sizeof(struct ip), hlen, &roff);
197 if (mo == NULL) {
198 DPRINTF(("ipsec_process_done : failed to inject"
199 "%u byte UDP for SA %s/%08lx\n",
200 hlen, ipsec_address(&saidx->dst),
201 (u_long) ntohl(sav->spi)));
202 error = ENOBUFS;
203 goto bad;
204 }
205
206 udp = (struct udphdr*) (mtod(mo, char*) + roff);
207 data = (uint64_t*) (udp + 1);
208
209 if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE)
210 *data = 0; /* NON-IKE Marker */
211
212 if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE)
213 udp->uh_sport = htons(UDP_ENCAP_ESPINUDP_PORT);
214 else
215 udp->uh_sport = key_portfromsaddr(&saidx->src);
216
217 udp->uh_dport = key_portfromsaddr(&saidx->dst);
218 udp->uh_sum = 0;
219 udp->uh_ulen = htons(m->m_pkthdr.len - (ip->ip_hl << 2));
220 }
221
222 switch (saidx->dst.sa.sa_family) {
223#ifdef INET
224 case AF_INET:
225 /* Fix the header length, for AH processing. */
226 ip = mtod(m, struct ip *);
227 ip->ip_len = htons(m->m_pkthdr.len);
228 if (sav->natt_type != 0)
229 ip->ip_p = IPPROTO_UDP;
230 break;
231#endif /* INET */
232#ifdef INET6
233 case AF_INET6:
234 /* Fix the header length, for AH processing. */
235 if (m->m_pkthdr.len < sizeof (struct ip6_hdr)) {
236 error = ENXIO;
237 goto bad;
238 }
239 if (m->m_pkthdr.len - sizeof (struct ip6_hdr) > IPV6_MAXPACKET) {
240 /* No jumbogram support. */
241 error = ENXIO; /*?*/
242 goto bad;
243 }
244 ip6 = mtod(m, struct ip6_hdr *);
245 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr));
246 if (sav->natt_type != 0)
247 ip6->ip6_nxt = IPPROTO_UDP;
248 break;
249#endif /* INET6 */
250 default:
251 DPRINTF(("ipsec_process_done: unknown protocol family %u\n",
252 saidx->dst.sa.sa_family));
253 error = ENXIO;
254 goto bad;
255 }
256
257 key_sa_recordxfer(sav, m);
258
259 /*
260 * If there's another (bundled) SA to apply, do so.
261 * Note that this puts a burden on the kernel stack size.
262 * If this is a problem we'll need to introduce a queue
263 * to set the packet on so we can unwind the stack before
264 * doing further processing.
265 */
266 if (isr->next) {
267 IPSEC_STATINC(IPSEC_STAT_OUT_BUNDLESA);
268 switch ( saidx->dst.sa.sa_family ) {
269#ifdef INET
270 case AF_INET:
271 return ipsec4_process_packet(m, isr->next, 0,0);
272#endif /* INET */
273#ifdef INET6
274 case AF_INET6:
275 return ipsec6_process_packet(m,isr->next);
276#endif /* INET6 */
277 default :
278 DPRINTF(("ipsec_process_done: unknown protocol family %u\n",
279 saidx->dst.sa.sa_family));
280 error = ENXIO;
281 goto bad;
282 }
283 }
284
285 /*
286 * We're done with IPsec processing,
287 * mark that we have already processed the packet
288 * transmit it packet using the appropriate network protocol (IP or IPv6).
289 */
290
291 if (ipsec_register_done(m, &error) < 0)
292 goto bad;
293
294 return ipsec_reinject_ipstack(m, saidx->dst.sa.sa_family);
295bad:
296 m_freem(m);
297 KEY_FREESAV(&sav);
298 return (error);
299}
300
301/*
302 * ipsec_nextisr can return :
303 * - isr == NULL and error != 0 => something is bad : the packet must be
304 * discarded
305 * - isr == NULL and error == 0 => no more rules to apply, ipsec processing
306 * is done, reinject it in ip stack
307 * - isr != NULL (error == 0) => we need to apply one rule to the packet
308 */
309static struct ipsecrequest *
310ipsec_nextisr(
311 struct mbuf *m,
312 struct ipsecrequest *isr,
313 int af,
314 struct secasindex *saidx,
315 int *error
316)
317{
318#define IPSEC_OSTAT(x, y, z) \
319do { \
320 switch (isr->saidx.proto) { \
321 case IPPROTO_ESP: \
322 ESP_STATINC(x); \
323 break; \
324 case IPPROTO_AH: \
325 AH_STATINC(y); \
326 break; \
327 default: \
328 IPCOMP_STATINC(z); \
329 break; \
330 } \
331} while (/*CONSTCOND*/0)
332
333 struct secasvar *sav;
334
335 IPSEC_SPLASSERT_SOFTNET("ipsec_nextisr");
336 IPSEC_ASSERT(af == AF_INET || af == AF_INET6,
337 ("ipsec_nextisr: invalid address family %u", af));
338again:
339 /*
340 * Craft SA index to search for proper SA. Note that
341 * we only fillin unspecified SA peers for transport
342 * mode; for tunnel mode they must already be filled in.
343 */
344 *saidx = isr->saidx;
345 if (isr->saidx.mode == IPSEC_MODE_TRANSPORT) {
346 /* Fillin unspecified SA peers only for transport mode */
347 if (af == AF_INET) {
348 struct sockaddr_in *sin;
349 struct ip *ip = mtod(m, struct ip *);
350
351 if (saidx->src.sa.sa_len == 0) {
352 sin = &saidx->src.sin;
353 sin->sin_len = sizeof(*sin);
354 sin->sin_family = AF_INET;
355 sin->sin_port = IPSEC_PORT_ANY;
356 sin->sin_addr = ip->ip_src;
357 }
358 if (saidx->dst.sa.sa_len == 0) {
359 sin = &saidx->dst.sin;
360 sin->sin_len = sizeof(*sin);
361 sin->sin_family = AF_INET;
362 sin->sin_port = IPSEC_PORT_ANY;
363 sin->sin_addr = ip->ip_dst;
364 }
365 } else {
366 struct sockaddr_in6 *sin6;
367 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
368
369 if (saidx->src.sin6.sin6_len == 0) {
370 sin6 = (struct sockaddr_in6 *)&saidx->src;
371 sin6->sin6_len = sizeof(*sin6);
372 sin6->sin6_family = AF_INET6;
373 sin6->sin6_port = IPSEC_PORT_ANY;
374 sin6->sin6_addr = ip6->ip6_src;
375 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) {
376 /* fix scope id for comparing SPD */
377 sin6->sin6_addr.s6_addr16[1] = 0;
378 sin6->sin6_scope_id =
379 ntohs(ip6->ip6_src.s6_addr16[1]);
380 }
381 }
382 if (saidx->dst.sin6.sin6_len == 0) {
383 sin6 = (struct sockaddr_in6 *)&saidx->dst;
384 sin6->sin6_len = sizeof(*sin6);
385 sin6->sin6_family = AF_INET6;
386 sin6->sin6_port = IPSEC_PORT_ANY;
387 sin6->sin6_addr = ip6->ip6_dst;
388 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) {
389 /* fix scope id for comparing SPD */
390 sin6->sin6_addr.s6_addr16[1] = 0;
391 sin6->sin6_scope_id =
392 ntohs(ip6->ip6_dst.s6_addr16[1]);
393 }
394 }
395 }
396 }
397
398 /*
399 * Lookup SA and validate it.
400 */
401 *error = key_checkrequest(isr, saidx);
402 if (*error != 0) {
403 /*
404 * IPsec processing is required, but no SA found.
405 * I assume that key_acquire() had been called
406 * to get/establish the SA. Here I discard
407 * this packet because it is responsibility for
408 * upper layer to retransmit the packet.
409 */
410 IPSEC_STATINC(IPSEC_STAT_OUT_NOSA);
411 goto bad;
412 }
413 sav = isr->sav;
414 /* sav may be NULL here if we have an USE rule */
415 if (sav == NULL) {
416 IPSEC_ASSERT(ipsec_get_reqlevel(isr) == IPSEC_LEVEL_USE,
417 ("ipsec_nextisr: no SA found, but required; level %u",
418 ipsec_get_reqlevel(isr)));
419 isr = isr->next;
420 /*
421 * No more rules to apply, return NULL isr and no error
422 * It can happen when the last rules are USE rules
423 * */
424 if (isr == NULL) {
425 *error = 0;
426 return isr;
427 }
428 goto again;
429 }
430
431 /*
432 * Check system global policy controls.
433 */
434 if ((isr->saidx.proto == IPPROTO_ESP && !esp_enable) ||
435 (isr->saidx.proto == IPPROTO_AH && !ah_enable) ||
436 (isr->saidx.proto == IPPROTO_IPCOMP && !ipcomp_enable)) {
437 DPRINTF(("ipsec_nextisr: IPsec outbound packet dropped due"
438 " to policy (check your sysctls)\n"));
439 IPSEC_OSTAT(ESP_STAT_PDROPS, AH_STAT_PDROPS,
440 IPCOMP_STAT_PDROPS);
441 *error = EHOSTUNREACH;
442 goto bad;
443 }
444
445 /*
446 * Sanity check the SA contents for the caller
447 * before they invoke the xform output method.
448 */
449 if (sav->tdb_xform == NULL) {
450 DPRINTF(("ipsec_nextisr: no transform for SA\n"));
451 IPSEC_OSTAT(ESP_STAT_NOXFORM, AH_STAT_NOXFORM,
452 IPCOMP_STAT_NOXFORM);
453 *error = EHOSTUNREACH;
454 goto bad;
455 }
456 return isr;
457bad:
458 IPSEC_ASSERT(*error != 0, ("ipsec_nextisr: error return w/ no error code"));
459 return NULL;
460#undef IPSEC_OSTAT
461}
462
463#ifdef INET
464/*
465 * IPsec output logic for IPv4.
466 */
467int
468ipsec4_process_packet(
469 struct mbuf *m,
470 struct ipsecrequest *isr,
471 int flags,
472 int tunalready
473)
474{
475 struct secasindex saidx;
476 struct secasvar *sav;
477 struct ip *ip;
478 int s, error, i, off;
479
480 IPSEC_ASSERT(m != NULL, ("ipsec4_process_packet: null mbuf"));
481 IPSEC_ASSERT(isr != NULL, ("ipsec4_process_packet: null isr"));
482
483 s = splsoftnet(); /* insure SA contents don't change */
484
485 isr = ipsec_nextisr(m, isr, AF_INET, &saidx, &error);
486 if (isr == NULL) {
487 if (error != 0) {
488 goto bad;
489 } else {
490 if (ipsec_register_done(m, &error) < 0)
491 goto bad;
492
493 splx(s);
494 return ipsec_reinject_ipstack(m, AF_INET);
495 }
496 }
497
498 sav = isr->sav;
499 if (!tunalready) {
500 union sockaddr_union *dst = &sav->sah->saidx.dst;
501 int setdf;
502
503 /*
504 * Collect IP_DF state from the outer header.
505 */
506 if (dst->sa.sa_family == AF_INET) {
507 if (m->m_len < sizeof (struct ip) &&
508 (m = m_pullup(m, sizeof (struct ip))) == NULL) {
509 error = ENOBUFS;
510 goto bad;
511 }
512 ip = mtod(m, struct ip *);
513 /* Honor system-wide control of how to handle IP_DF */
514 switch (ip4_ipsec_dfbit) {
515 case 0: /* clear in outer header */
516 case 1: /* set in outer header */
517 setdf = ip4_ipsec_dfbit;
518 break;
519 default: /* propagate to outer header */
520 setdf = ip->ip_off;
521#ifndef __FreeBSD__
522 /* On FreeBSD, ip_off and ip_len assumed in host endian. */
523 setdf = ntohs(setdf);
524#endif
525 setdf = htons(setdf & IP_DF);
526 break;
527 }
528 } else {
529 ip = NULL; /* keep compiler happy */
530 setdf = 0;
531 }
532 /* Do the appropriate encapsulation, if necessary */
533 if (isr->saidx.mode == IPSEC_MODE_TUNNEL || /* Tunnel requ'd */
534 dst->sa.sa_family != AF_INET || /* PF mismatch */
535#if 0
536 (sav->flags & SADB_X_SAFLAGS_TUNNEL) || /* Tunnel requ'd */
537 sav->tdb_xform->xf_type == XF_IP4 || /* ditto */
538#endif
539 (dst->sa.sa_family == AF_INET && /* Proxy */
540 dst->sin.sin_addr.s_addr != INADDR_ANY &&
541 dst->sin.sin_addr.s_addr != ip->ip_dst.s_addr)) {
542 struct mbuf *mp;
543
544 /* Fix IPv4 header checksum and length */
545 if (m->m_len < sizeof (struct ip) &&
546 (m = m_pullup(m, sizeof (struct ip))) == NULL) {
547 error = ENOBUFS;
548 goto bad;
549 }
550 ip = mtod(m, struct ip *);
551 ip->ip_len = htons(m->m_pkthdr.len);
552 ip->ip_sum = 0;
553 ip->ip_sum = in_cksum(m, ip->ip_hl << 2);
554
555 /* Encapsulate the packet */
556 error = ipip_output(m, isr, &mp, 0, 0);
557 if (mp == NULL && !error) {
558 /* Should never happen. */
559 DPRINTF(("ipsec4_process_packet: ipip_output "
560 "returns no mbuf and no error!"));
561 error = EFAULT;
562 }
563 if (error) {
564 if (mp) {
565 /* XXX: Should never happen! */
566 m_freem(mp);
567 }
568 m = NULL; /* ipip_output() already freed it */
569 goto bad;
570 }
571 m = mp, mp = NULL;
572 /*
573 * ipip_output clears IP_DF in the new header. If
574 * we need to propagate IP_DF from the outer header,
575 * then we have to do it here.
576 *
577 * XXX shouldn't assume what ipip_output does.
578 */
579 if (dst->sa.sa_family == AF_INET && setdf) {
580 if (m->m_len < sizeof (struct ip) &&
581 (m = m_pullup(m, sizeof (struct ip))) == NULL) {
582 error = ENOBUFS;
583 goto bad;
584 }
585 ip = mtod(m, struct ip *);
586 ip->ip_off |= IP_OFF_CONVERT(IP_DF);
587 }
588 }
589 }
590
591 /*
592 * Dispatch to the appropriate IPsec transform logic. The
593 * packet will be returned for transmission after crypto
594 * processing, etc. are completed. For encapsulation we
595 * bypass this call because of the explicit call done above
596 * (necessary to deal with IP_DF handling for IPv4).
597 *
598 * NB: m & sav are ``passed to caller'' who's reponsible for
599 * for reclaiming their resources.
600 */
601 if (sav->tdb_xform->xf_type != XF_IP4) {
602 union sockaddr_union *dst = &sav->sah->saidx.dst;
603 if (dst->sa.sa_family == AF_INET) {
604 ip = mtod(m, struct ip *);
605 i = ip->ip_hl << 2;
606 off = offsetof(struct ip, ip_p);
607 } else {
608 i = sizeof(struct ip6_hdr);
609 off = offsetof(struct ip6_hdr, ip6_nxt);
610 }
611 error = (*sav->tdb_xform->xf_output)(m, isr, NULL, i, off);
612 } else {
613 error = ipsec_process_done(m, isr);
614 }
615 splx(s);
616 return error;
617bad:
618 splx(s);
619 if (m)
620 m_freem(m);
621 return error;
622}
623#endif
624
625#ifdef INET6
626static void
627compute_ipsec_pos(struct mbuf *m, int *i, int *off)
628{
629 int nxt;
630 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr*);
631 struct ip6_ext ip6e;
632 int dstopt = 0;
633
634 *i = sizeof(struct ip6_hdr);
635 *off = offsetof(struct ip6_hdr, ip6_nxt);
636 nxt = ip6->ip6_nxt;
637
638 /*
639 * chase mbuf chain to find the appropriate place to
640 * put AH/ESP/IPcomp header.
641 * IPv6 hbh dest1 rthdr ah* [esp* dest2 payload]
642 */
643 do {
644 switch (nxt) {
645 case IPPROTO_AH:
646 case IPPROTO_ESP:
647 case IPPROTO_IPCOMP:
648 /*
649 * we should not skip security header added
650 * beforehand.
651 */
652 return;
653
654 case IPPROTO_HOPOPTS:
655 case IPPROTO_DSTOPTS:
656 case IPPROTO_ROUTING:
657 /*
658 * if we see 2nd destination option header,
659 * we should stop there.
660 */
661 if (nxt == IPPROTO_DSTOPTS && dstopt)
662 return;
663
664 if (nxt == IPPROTO_DSTOPTS) {
665 /*
666 * seen 1st or 2nd destination option.
667 * next time we see one, it must be 2nd.
668 */
669 dstopt = 1;
670 } else if (nxt == IPPROTO_ROUTING) {
671 /*
672 * if we see destionation option next
673 * time, it must be dest2.
674 */
675 dstopt = 2;
676 }
677
678 /* skip this header */
679 m_copydata(m, *i, sizeof(ip6e), &ip6e);
680 nxt = ip6e.ip6e_nxt;
681 *off = *i + offsetof(struct ip6_ext, ip6e_nxt);
682 /*
683 * we will never see nxt == IPPROTO_AH
684 * so it is safe to omit AH case.
685 */
686 *i += (ip6e.ip6e_len + 1) << 3;
687 break;
688 default:
689 return;
690 }
691 } while (*i < m->m_pkthdr.len);
692}
693
694static int
695in6_sa_equal_addrwithscope(const struct sockaddr_in6 *sa, const struct in6_addr *ia)
696{
697 struct in6_addr ia2;
698
699 memcpy(&ia2, &sa->sin6_addr, sizeof(ia2));
700 if (IN6_IS_SCOPE_LINKLOCAL(&sa->sin6_addr))
701 ia2.s6_addr16[1] = htons(sa->sin6_scope_id);
702
703 return IN6_ARE_ADDR_EQUAL(ia, &ia2);
704}
705
706int
707ipsec6_process_packet(
708 struct mbuf *m,
709 struct ipsecrequest *isr
710 )
711{
712 struct secasindex saidx;
713 struct secasvar *sav;
714 struct ip6_hdr *ip6;
715 int s, error, i, off;
716 union sockaddr_union *dst;
717
718 IPSEC_ASSERT(m != NULL, ("ipsec6_process_packet: null mbuf"));
719 IPSEC_ASSERT(isr != NULL, ("ipsec6_process_packet: null isr"));
720
721 s = splsoftnet(); /* insure SA contents don't change */
722
723 isr = ipsec_nextisr(m, isr, AF_INET6, &saidx, &error);
724 if (isr == NULL) {
725 if (error != 0) {
726 /* XXX Should we send a notification ? */
727 goto bad;
728 } else {
729 if (ipsec_register_done(m, &error) < 0)
730 goto bad;
731
732 splx(s);
733 return ipsec_reinject_ipstack(m, AF_INET6);
734 }
735 }
736
737 sav = isr->sav;
738 dst = &sav->sah->saidx.dst;
739
740 ip6 = mtod(m, struct ip6_hdr *); /* XXX */
741
742 /* Do the appropriate encapsulation, if necessary */
743 if (isr->saidx.mode == IPSEC_MODE_TUNNEL || /* Tunnel requ'd */
744 dst->sa.sa_family != AF_INET6 || /* PF mismatch */
745 ((dst->sa.sa_family == AF_INET6) &&
746 (!IN6_IS_ADDR_UNSPECIFIED(&dst->sin6.sin6_addr)) &&
747 (!in6_sa_equal_addrwithscope(&dst->sin6,
748 &ip6->ip6_dst)))) {
749 struct mbuf *mp;
750
751 /* Fix IPv6 header payload length. */
752 if (m->m_len < sizeof(struct ip6_hdr))
753 if ((m = m_pullup(m,sizeof(struct ip6_hdr))) == NULL)
754 return ENOBUFS;
755
756 if (m->m_pkthdr.len - sizeof(*ip6) > IPV6_MAXPACKET) {
757 /* No jumbogram support. */
758 m_freem(m);
759 return ENXIO; /*XXX*/
760 }
761
762 ip6 = mtod(m, struct ip6_hdr *);
763 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(*ip6));
764
765 /* Encapsulate the packet */
766 error = ipip_output(m, isr, &mp, 0, 0);
767 if (mp == NULL && !error) {
768 /* Should never happen. */
769 DPRINTF(("ipsec6_process_packet: ipip_output "
770 "returns no mbuf and no error!"));
771 error = EFAULT;
772 }
773
774 if (error) {
775 if (mp) {
776 /* XXX: Should never happen! */
777 m_freem(mp);
778 }
779 m = NULL; /* ipip_output() already freed it */
780 goto bad;
781 }
782
783 m = mp;
784 mp = NULL;
785 }
786
787 if (dst->sa.sa_family == AF_INET) {
788 struct ip *ip;
789 ip = mtod(m, struct ip *);
790 i = ip->ip_hl << 2;
791 off = offsetof(struct ip, ip_p);
792 } else {
793 compute_ipsec_pos(m, &i, &off);
794 }
795 error = (*sav->tdb_xform->xf_output)(m, isr, NULL, i, off);
796 splx(s);
797 return error;
798bad:
799 splx(s);
800 if (m)
801 m_freem(m);
802 return error;
803}
804#endif /*INET6*/
805