1/*-
2 * Copyright (c) 2002, 2003 Sam Leffler, Errno Consulting
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
26 * $FreeBSD: head/sys/netipsec/ipsec_output.c 151967 2005-11-02 13:46:32Z andre $
27 */
28
29/*
30 * IPsec output processing.
31 */
32#include "opt_inet.h"
33#include "opt_inet6.h"
34#include "opt_ipsec.h"
35
36#include <sys/param.h>
37#include <sys/systm.h>
38#include <sys/mbuf.h>
39#include <sys/domain.h>
40#include <sys/protosw.h>
41#include <sys/socket.h>
42#include <sys/errno.h>
43#include <sys/syslog.h>
44
45#include <net/if.h>
46#include <net/route.h>
47
48#include <netinet/in.h>
49#include <netinet/in_systm.h>
50#include <netinet/ip.h>
51#include <netinet/ip_var.h>
52#include <netinet/in_var.h>
53#include <netinet/ip_ecn.h>
54#ifdef INET6
55#include <netinet6/ip6_ecn.h>
56#endif
57
58#include <netinet/ip6.h>
59#ifdef INET6
60#include <netinet6/ip6_var.h>
61#endif
62#include <netinet/in_pcb.h>
63#ifdef INET6
64#include <netinet/icmp6.h>
65#endif
66
67#include <netipsec/ipsec.h>
68#ifdef INET6
69#include <netipsec/ipsec6.h>
70#endif
71#include <netipsec/ah_var.h>
72#include <netipsec/esp_var.h>
73#include <netipsec/ipcomp_var.h>
74
75#include <netipsec/xform.h>
76
77#include <netipsec/key.h>
78#include <netipsec/keydb.h>
79#include <netipsec/key_debug.h>
80
81#include <machine/in_cksum.h>
82
83int
84ipsec_process_done(struct mbuf *m, struct ipsecrequest *isr)
85{
86 struct tdb_ident *tdbi;
87 struct m_tag *mtag;
88 struct secasvar *sav;
89 struct secasindex *saidx;
90 int error;
91
92 IPSEC_SPLASSERT_SOFTNET(__func__);
93
94 IPSEC_ASSERT(m != NULL, ("null mbuf"));
95 IPSEC_ASSERT(isr != NULL, ("null ISR"));
96 sav = isr->sav;
97 IPSEC_ASSERT(sav != NULL, ("null SA"));
98 IPSEC_ASSERT(sav->sah != NULL, ("null SAH"));
99
100 saidx = &sav->sah->saidx;
101 switch (saidx->dst.sa.sa_family) {
102#ifdef INET
103 case AF_INET:
104 /* Fix the header length, for AH processing. */
105 mtod(m, struct ip *)->ip_len = htons(m->m_pkthdr.len);
106 break;
107#endif /* INET */
108#ifdef INET6
109 case AF_INET6:
110 /* Fix the header length, for AH processing. */
111 if (m->m_pkthdr.len < sizeof (struct ip6_hdr)) {
112 error = ENXIO;
113 goto bad;
114 }
115 if (m->m_pkthdr.len - sizeof (struct ip6_hdr) > IPV6_MAXPACKET) {
116 /* No jumbogram support. */
117 error = ENXIO; /*?*/
118 goto bad;
119 }
120 mtod(m, struct ip6_hdr *)->ip6_plen =
121 htons(m->m_pkthdr.len - sizeof(struct ip6_hdr));
122 break;
123#endif /* INET6 */
124 default:
125 DPRINTF(("%s: unknown protocol family %u\n", __func__,
126 saidx->dst.sa.sa_family));
127 error = ENXIO;
128 goto bad;
129 }
130
131 /*
132 * Add a record of what we've done or what needs to be done to the
133 * packet.
134 */
135 mtag = m_tag_get(PACKET_TAG_IPSEC_OUT_DONE,
136 sizeof(struct tdb_ident), M_NOWAIT);
137 if (mtag == NULL) {
138 DPRINTF(("%s: could not get packet tag\n", __func__));
139 error = ENOMEM;
140 goto bad;
141 }
142
143 tdbi = (struct tdb_ident *)(mtag + 1);
144 tdbi->dst = saidx->dst;
145 tdbi->proto = saidx->proto;
146 tdbi->spi = sav->spi;
147 m_tag_prepend(m, mtag);
148
149 /*
150 * If there's another (bundled) SA to apply, do so.
151 * Note that this puts a burden on the kernel stack size.
152 * If this is a problem we'll need to introduce a queue
153 * to set the packet on so we can unwind the stack before
154 * doing further processing.
155 */
156 if (isr->next) {
157 newipsecstat.ips_out_bundlesa++;
158 return ipsec4_process_packet(m, isr->next, 0, 0);
159 }
160 key_sa_recordxfer(sav, m); /* record data transfer */
161
162 /*
163 * We're done with IPsec processing, transmit the packet using the
164 * appropriate network protocol (IP or IPv6). SPD lookup will be
165 * performed again there.
166 */
167 switch (saidx->dst.sa.sa_family) {
168#ifdef INET
169 struct ip *ip;
170 case AF_INET:
171 ip = mtod(m, struct ip *);
172 ip->ip_len = ntohs(ip->ip_len);
173 ip->ip_off = ntohs(ip->ip_off);
174
175 return ip_output(m, NULL, NULL, IP_RAWOUTPUT, NULL, NULL);
176#endif /* INET */
177#ifdef INET6
178 case AF_INET6:
179 /*
180 * We don't need massage, IPv6 header fields are always in
181 * net endian.
182 */
183 return ip6_output(m, NULL, NULL, 0, NULL, NULL, NULL);
184#endif /* INET6 */
185 }
186 panic("ipsec_process_done");
187bad:
188 m_freem(m);
189 KEY_FREESAV(&sav);
190 return (error);
191}
192
193static struct ipsecrequest *
194ipsec_nextisr(
195 struct mbuf *m,
196 struct ipsecrequest *isr,
197 int af,
198 struct secasindex *saidx,
199 int *error
200)
201{
202#define IPSEC_OSTAT(x,y,z) (isr->saidx.proto == IPPROTO_ESP ? (x)++ : \
203 isr->saidx.proto == IPPROTO_AH ? (y)++ : (z)++)
204 struct secasvar *sav;
205
206 IPSEC_SPLASSERT_SOFTNET(__func__);
207 IPSECREQUEST_LOCK_ASSERT(isr);
208
209 IPSEC_ASSERT(af == AF_INET || af == AF_INET6,
210 ("invalid address family %u", af));
211again:
212 /*
213 * Craft SA index to search for proper SA. Note that
214 * we only fillin unspecified SA peers for transport
215 * mode; for tunnel mode they must already be filled in.
216 */
217 *saidx = isr->saidx;
218 if (isr->saidx.mode == IPSEC_MODE_TRANSPORT) {
219 /* Fillin unspecified SA peers only for transport mode */
220 if (af == AF_INET) {
221 struct sockaddr_in *sin;
222 struct ip *ip = mtod(m, struct ip *);
223
224 if (saidx->src.sa.sa_len == 0) {
225 sin = &saidx->src.sin;
226 sin->sin_len = sizeof(*sin);
227 sin->sin_family = AF_INET;
228 sin->sin_port = IPSEC_PORT_ANY;
229 sin->sin_addr = ip->ip_src;
230 }
231 if (saidx->dst.sa.sa_len == 0) {
232 sin = &saidx->dst.sin;
233 sin->sin_len = sizeof(*sin);
234 sin->sin_family = AF_INET;
235 sin->sin_port = IPSEC_PORT_ANY;
236 sin->sin_addr = ip->ip_dst;
237 }
238 } else {
239 struct sockaddr_in6 *sin6;
240 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
241
242 if (saidx->src.sin6.sin6_len == 0) {
243 sin6 = (struct sockaddr_in6 *)&saidx->src;
244 sin6->sin6_len = sizeof(*sin6);
245 sin6->sin6_family = AF_INET6;
246 sin6->sin6_port = IPSEC_PORT_ANY;
247 sin6->sin6_addr = ip6->ip6_src;
248 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) {
249 /* fix scope id for comparing SPD */
250 sin6->sin6_addr.s6_addr16[1] = 0;
251 sin6->sin6_scope_id =
252 ntohs(ip6->ip6_src.s6_addr16[1]);
253 }
254 }
255 if (saidx->dst.sin6.sin6_len == 0) {
256 sin6 = (struct sockaddr_in6 *)&saidx->dst;
257 sin6->sin6_len = sizeof(*sin6);
258 sin6->sin6_family = AF_INET6;
259 sin6->sin6_port = IPSEC_PORT_ANY;
260 sin6->sin6_addr = ip6->ip6_dst;
261 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) {
262 /* fix scope id for comparing SPD */
263 sin6->sin6_addr.s6_addr16[1] = 0;
264 sin6->sin6_scope_id =
265 ntohs(ip6->ip6_dst.s6_addr16[1]);
266 }
267 }
268 }
269 }
270
271 /*
272 * Lookup SA and validate it.
273 */
274 *error = key_checkrequest(isr, saidx);
275 if (*error != 0) {
276 /*
277 * IPsec processing is required, but no SA found.
278 * I assume that key_acquire() had been called
279 * to get/establish the SA. Here I discard
280 * this packet because it is responsibility for
281 * upper layer to retransmit the packet.
282 */
283 newipsecstat.ips_out_nosa++;
284 goto bad;
285 }
286 sav = isr->sav;
287 if (sav == NULL) { /* XXX valid return */
288 IPSEC_ASSERT(ipsec_get_reqlevel(isr) == IPSEC_LEVEL_USE,
289 ("no SA found, but required; level %u",
290 ipsec_get_reqlevel(isr)));
291 IPSECREQUEST_UNLOCK(isr);
292 isr = isr->next;
293 if (isr == NULL) {
294 /*XXXstatistic??*/
295 *error = EINVAL; /*XXX*/
296 return isr;
297 }
298 IPSECREQUEST_LOCK(isr);
299 goto again;
300 }
301
302 /*
303 * Check system global policy controls.
304 */
305 if ((isr->saidx.proto == IPPROTO_ESP && !esp_enable) ||
306 (isr->saidx.proto == IPPROTO_AH && !ah_enable) ||
307 (isr->saidx.proto == IPPROTO_IPCOMP && !ipcomp_enable)) {
308 DPRINTF(("%s: IPsec outbound packet dropped due"
309 " to policy (check your sysctls)\n", __func__));
310 IPSEC_OSTAT(espstat.esps_pdrops, ahstat.ahs_pdrops,
311 ipcompstat.ipcomps_pdrops);
312 *error = EHOSTUNREACH;
313 goto bad;
314 }
315
316 /*
317 * Sanity check the SA contents for the caller
318 * before they invoke the xform output method.
319 */
320 if (sav->tdb_xform == NULL) {
321 DPRINTF(("%s: no transform for SA\n", __func__));
322 IPSEC_OSTAT(espstat.esps_noxform, ahstat.ahs_noxform,
323 ipcompstat.ipcomps_noxform);
324 *error = EHOSTUNREACH;
325 goto bad;
326 }
327 return isr;
328bad:
329 IPSEC_ASSERT(*error != 0, ("error return w/ no error code"));
330 IPSECREQUEST_UNLOCK(isr);
331 return NULL;
332#undef IPSEC_OSTAT
333}
334
335#ifdef INET
336/*
337 * IPsec output logic for IPv4.
338 */
339int
340ipsec4_process_packet(
341 struct mbuf *m,
342 struct ipsecrequest *isr,
343 int flags,
344 int tunalready)
345{
346 struct secasindex saidx;
347 struct secasvar *sav;
348 struct ip *ip;
349 int error, i, off;
350
351 IPSEC_ASSERT(m != NULL, ("null mbuf"));
352 IPSEC_ASSERT(isr != NULL, ("null isr"));
353
354 IPSECREQUEST_LOCK(isr); /* insure SA contents don't change */
355
356 isr = ipsec_nextisr(m, isr, AF_INET, &saidx, &error);
357 if (isr == NULL)
358 goto bad;
359
360 sav = isr->sav;
361 if (!tunalready) {
362 union sockaddr_union *dst = &sav->sah->saidx.dst;
363 int setdf;
364
365 /*
366 * Collect IP_DF state from the outer header.
367 */
368 if (dst->sa.sa_family == AF_INET) {
369 if (m->m_len < sizeof (struct ip) &&
370 (m = m_pullup(m, sizeof (struct ip))) == NULL) {
371 error = ENOBUFS;
372 goto bad;
373 }
374 ip = mtod(m, struct ip *);
375 /* Honor system-wide control of how to handle IP_DF */
376 switch (ip4_ipsec_dfbit) {
377 case 0: /* clear in outer header */
378 case 1: /* set in outer header */
379 setdf = ip4_ipsec_dfbit;
380 break;
381 default: /* propagate to outer header */
382 setdf = ntohs(ip->ip_off & IP_DF);
383 break;
384 }
385 } else {
386 ip = NULL; /* keep compiler happy */
387 setdf = 0;
388 }
389 /* Do the appropriate encapsulation, if necessary */
390 if (isr->saidx.mode == IPSEC_MODE_TUNNEL || /* Tunnel requ'd */
391 dst->sa.sa_family != AF_INET || /* PF mismatch */
392#if 0
393 (sav->flags & SADB_X_SAFLAGS_TUNNEL) || /* Tunnel requ'd */
394 sav->tdb_xform->xf_type == XF_IP4 || /* ditto */
395#endif
396 (dst->sa.sa_family == AF_INET && /* Proxy */
397 dst->sin.sin_addr.s_addr != INADDR_ANY &&
398 dst->sin.sin_addr.s_addr != ip->ip_dst.s_addr)) {
399 struct mbuf *mp;
400
401 /* Fix IPv4 header checksum and length */
402 if (m->m_len < sizeof (struct ip) &&
403 (m = m_pullup(m, sizeof (struct ip))) == NULL) {
404 error = ENOBUFS;
405 goto bad;
406 }
407 ip = mtod(m, struct ip *);
408 ip->ip_len = htons(m->m_pkthdr.len);
409 ip->ip_sum = 0;
410#ifdef _IP_VHL
411 if (ip->ip_vhl == IP_VHL_BORING)
412 ip->ip_sum = in_cksum_hdr(ip);
413 else
414 ip->ip_sum = in_cksum(m,
415 _IP_VHL_HL(ip->ip_vhl) << 2);
416#else
417 ip->ip_sum = in_cksum(m, ip->ip_hl << 2);
418#endif
419
420 /* Encapsulate the packet */
421 error = ipip_output(m, isr, &mp, 0, 0);
422 if (mp == NULL && !error) {
423 /* Should never happen. */
424 DPRINTF(("%s: ipip_output returns no mbuf and "
425 "no error!", __func__));
426 error = EFAULT;
427 }
428 if (error) {
429 if (mp) {
430 /* XXX: Should never happen! */
431 m_freem(mp);
432 }
433 m = NULL; /* ipip_output() already freed it */
434 goto bad;
435 }
436 m = mp, mp = NULL;
437 /*
438 * ipip_output clears IP_DF in the new header. If
439 * we need to propagate IP_DF from the outer header,
440 * then we have to do it here.
441 *
442 * XXX shouldn't assume what ipip_output does.
443 */
444 if (dst->sa.sa_family == AF_INET && setdf) {
445 if (m->m_len < sizeof (struct ip) &&
446 (m = m_pullup(m, sizeof (struct ip))) == NULL) {
447 error = ENOBUFS;
448 goto bad;
449 }
450 ip = mtod(m, struct ip *);
451 ip->ip_off = ntohs(ip->ip_off);
452 ip->ip_off |= IP_DF;
453 ip->ip_off = htons(ip->ip_off);
454 }
455 }
456 }
457
458 /*
459 * Dispatch to the appropriate IPsec transform logic. The
460 * packet will be returned for transmission after crypto
461 * processing, etc. are completed. For encapsulation we
462 * bypass this call because of the explicit call done above
463 * (necessary to deal with IP_DF handling for IPv4).
464 *
465 * NB: m & sav are ``passed to caller'' who's reponsible for
466 * for reclaiming their resources.
467 */
468 if (sav->tdb_xform->xf_type != XF_IP4) {
469 ip = mtod(m, struct ip *);
470 i = ip->ip_hl << 2;
471 off = offsetof(struct ip, ip_p);
472 error = (*sav->tdb_xform->xf_output)(m, isr, NULL, i, off);
473 } else {
474 error = ipsec_process_done(m, isr);
475 }
476 IPSECREQUEST_UNLOCK(isr);
477 return error;
478bad:
479 if (isr)
480 IPSECREQUEST_UNLOCK(isr);
481 if (m)
482 m_freem(m);
483 return error;
484}
485#endif
486
487#ifdef INET6
488/*
489 * Chop IP6 header from the payload.
490 */
491static struct mbuf *
492ipsec6_splithdr(struct mbuf *m)
493{
494 struct mbuf *mh;
495 struct ip6_hdr *ip6;
496 int hlen;
497
498 IPSEC_ASSERT(m->m_len >= sizeof (struct ip6_hdr),
499 ("first mbuf too short, len %u", m->m_len));
500 ip6 = mtod(m, struct ip6_hdr *);
501 hlen = sizeof(struct ip6_hdr);
502 if (m->m_len > hlen) {
503 MGETHDR(mh, M_DONTWAIT, MT_DATA);
504 if (!mh) {
505 m_freem(m);
506 return NULL;
507 }
508 M_MOVE_PKTHDR(mh, m);
509 MH_ALIGN(mh, hlen);
510 m->m_len -= hlen;
511 m->m_data += hlen;
512 mh->m_next = m;
513 m = mh;
514 m->m_len = hlen;
515 bcopy((caddr_t)ip6, mtod(m, caddr_t), hlen);
516 } else if (m->m_len < hlen) {
517 m = m_pullup(m, hlen);
518 if (!m)
519 return NULL;
520 }
521 return m;
522}
523
524/*
525 * IPsec output logic for IPv6, transport mode.
526 */
527int
528ipsec6_output_trans(
529 struct ipsec_output_state *state,
530 u_char *nexthdrp,
531 struct mbuf *mprev,
532 struct secpolicy *sp,
533 int flags,
534 int *tun)
535{
536 struct ipsecrequest *isr;
537 struct secasindex saidx;
538 int error = 0;
539 struct mbuf *m;
540
541 IPSEC_ASSERT(state != NULL, ("null state"));
542 IPSEC_ASSERT(state->m != NULL, ("null m"));
543 IPSEC_ASSERT(nexthdrp != NULL, ("null nexthdrp"));
544 IPSEC_ASSERT(mprev != NULL, ("null mprev"));
545 IPSEC_ASSERT(sp != NULL, ("null sp"));
546 IPSEC_ASSERT(tun != NULL, ("null tun"));
547
548 KEYDEBUG(KEYDEBUG_IPSEC_DATA,
549 printf("%s: applyed SP\n", __func__);
550 kdebug_secpolicy(sp));
551
552 isr = sp->req;
553 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) {
554 /* the rest will be handled by ipsec6_output_tunnel() */
555 *tun = 1; /* need tunnel-mode processing */
556 return 0;
557 }
558
559 *tun = 0;
560 m = state->m;
561
562 isr = ipsec_nextisr(m, isr, AF_INET6, &saidx, &error);
563 if (isr == NULL) {
564#ifdef notdef
565 /* XXX should notification be done for all errors ? */
566 /*
567 * Notify the fact that the packet is discarded
568 * to ourselves. I believe this is better than
569 * just silently discarding. (jinmei@kame.net)
570 * XXX: should we restrict the error to TCP packets?
571 * XXX: should we directly notify sockets via
572 * pfctlinputs?
573 */
574 icmp6_error(m, ICMP6_DST_UNREACH,
575 ICMP6_DST_UNREACH_ADMIN, 0);
576 m = NULL; /* NB: icmp6_error frees mbuf */
577#endif
578 goto bad;
579 }
580
581 return (*isr->sav->tdb_xform->xf_output)(m, isr, NULL,
582 sizeof (struct ip6_hdr),
583 offsetof(struct ip6_hdr, ip6_nxt));
584bad:
585 if (m)
586 m_freem(m);
587 state->m = NULL;
588 return error;
589}
590
591static int
592ipsec6_encapsulate(struct mbuf *m, struct secasvar *sav)
593{
594 struct ip6_hdr *oip6;
595 struct ip6_hdr *ip6;
596 size_t plen;
597
598 /* can't tunnel between different AFs */
599 if (sav->sah->saidx.src.sa.sa_family != AF_INET6 ||
600 sav->sah->saidx.dst.sa.sa_family != AF_INET6) {
601 m_freem(m);
602 return EINVAL;
603 }
604 IPSEC_ASSERT(m->m_len != sizeof (struct ip6_hdr),
605 ("mbuf wrong size; len %u", m->m_len));
606
607
608 /*
609 * grow the mbuf to accomodate the new IPv6 header.
610 */
611 plen = m->m_pkthdr.len;
612 if (M_LEADINGSPACE(m->m_next) < sizeof(struct ip6_hdr)) {
613 struct mbuf *n;
614 MGET(n, M_DONTWAIT, MT_DATA);
615 if (!n) {
616 m_freem(m);
617 return ENOBUFS;
618 }
619 n->m_len = sizeof(struct ip6_hdr);
620 n->m_next = m->m_next;
621 m->m_next = n;
622 m->m_pkthdr.len += sizeof(struct ip6_hdr);
623 oip6 = mtod(n, struct ip6_hdr *);
624 } else {
625 m->m_next->m_len += sizeof(struct ip6_hdr);
626 m->m_next->m_data -= sizeof(struct ip6_hdr);
627 m->m_pkthdr.len += sizeof(struct ip6_hdr);
628 oip6 = mtod(m->m_next, struct ip6_hdr *);
629 }
630 ip6 = mtod(m, struct ip6_hdr *);
631 bcopy((caddr_t)ip6, (caddr_t)oip6, sizeof(struct ip6_hdr));
632
633 /* Fake link-local scope-class addresses */
634 if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_src))
635 oip6->ip6_src.s6_addr16[1] = 0;
636 if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_dst))
637 oip6->ip6_dst.s6_addr16[1] = 0;
638
639 /* construct new IPv6 header. see RFC 2401 5.1.2.2 */
640 /* ECN consideration. */
641 ip6_ecn_ingress(ip6_ipsec_ecn, &ip6->ip6_flow, &oip6->ip6_flow);
642 if (plen < IPV6_MAXPACKET - sizeof(struct ip6_hdr))
643 ip6->ip6_plen = htons(plen);
644 else {
645 /* ip6->ip6_plen will be updated in ip6_output() */
646 }
647 ip6->ip6_nxt = IPPROTO_IPV6;
648 sav->sah->saidx.src.sin6.sin6_addr = ip6->ip6_src;
649 sav->sah->saidx.dst.sin6.sin6_addr = ip6->ip6_dst;
650 ip6->ip6_hlim = IPV6_DEFHLIM;
651
652 /* XXX Should ip6_src be updated later ? */
653
654 return 0;
655}
656
657/*
658 * IPsec output logic for IPv6, tunnel mode.
659 */
660int
661ipsec6_output_tunnel(struct ipsec_output_state *state, struct secpolicy *sp, int flags)
662{
663 struct ip6_hdr *ip6;
664 struct ipsecrequest *isr;
665 struct secasindex saidx;
666 int error;
667 struct sockaddr_in6* dst6;
668 struct mbuf *m;
669
670 IPSEC_ASSERT(state != NULL, ("null state"));
671 IPSEC_ASSERT(state->m != NULL, ("null m"));
672 IPSEC_ASSERT(sp != NULL, ("null sp"));
673
674 KEYDEBUG(KEYDEBUG_IPSEC_DATA,
675 printf("%s: applyed SP\n", __func__);
676 kdebug_secpolicy(sp));
677
678 m = state->m;
679 /*
680 * transport mode ipsec (before the 1st tunnel mode) is already
681 * processed by ipsec6_output_trans().
682 */
683 for (isr = sp->req; isr; isr = isr->next) {
684 if (isr->saidx.mode == IPSEC_MODE_TUNNEL)
685 break;
686 }
687 isr = ipsec_nextisr(m, isr, AF_INET6, &saidx, &error);
688 if (isr == NULL)
689 goto bad;
690
691 /*
692 * There may be the case that SA status will be changed when
693 * we are refering to one. So calling splsoftnet().
694 */
695 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) {
696 /*
697 * build IPsec tunnel.
698 */
699 /* XXX should be processed with other familiy */
700 if (isr->sav->sah->saidx.src.sa.sa_family != AF_INET6) {
701 ipseclog((LOG_ERR, "%s: family mismatched between "
702 "inner and outer, spi=%u\n", __func__,
703 ntohl(isr->sav->spi)));
704 newipsecstat.ips_out_inval++;
705 error = EAFNOSUPPORT;
706 goto bad;
707 }
708
709 m = ipsec6_splithdr(m);
710 if (!m) {
711 newipsecstat.ips_out_nomem++;
712 error = ENOMEM;
713 goto bad;
714 }
715 error = ipsec6_encapsulate(m, isr->sav);
716 if (error) {
717 m = NULL;
718 goto bad;
719 }
720 ip6 = mtod(m, struct ip6_hdr *);
721
722 state->ro = &isr->sav->sah->sa_route;
723 state->dst = (struct sockaddr *)&state->ro->ro_dst;
724 dst6 = (struct sockaddr_in6 *)state->dst;
725 if (state->ro->ro_rt
726 && ((state->ro->ro_rt->rt_flags & RTF_UP) == 0
727 || !IN6_ARE_ADDR_EQUAL(&dst6->sin6_addr, &ip6->ip6_dst))) {
728 RTFREE(state->ro->ro_rt);
729 state->ro->ro_rt = NULL;
730 }
731 if (state->ro->ro_rt == 0) {
732 bzero(dst6, sizeof(*dst6));
733 dst6->sin6_family = AF_INET6;
734 dst6->sin6_len = sizeof(*dst6);
735 dst6->sin6_addr = ip6->ip6_dst;
736 rtalloc(state->ro);
737 }
738 if (state->ro->ro_rt == 0) {
739 ip6stat.ip6s_noroute++;
740 newipsecstat.ips_out_noroute++;
741 error = EHOSTUNREACH;
742 goto bad;
743 }
744
745 /* adjust state->dst if tunnel endpoint is offlink */
746 if (state->ro->ro_rt->rt_flags & RTF_GATEWAY) {
747 state->dst = (struct sockaddr *)state->ro->ro_rt->rt_gateway;
748 dst6 = (struct sockaddr_in6 *)state->dst;
749 }
750 }
751
752 m = ipsec6_splithdr(m);
753 if (!m) {
754 newipsecstat.ips_out_nomem++;
755 error = ENOMEM;
756 goto bad;
757 }
758 ip6 = mtod(m, struct ip6_hdr *);
759 return (*isr->sav->tdb_xform->xf_output)(m, isr, NULL,
760 sizeof (struct ip6_hdr),
761 offsetof(struct ip6_hdr, ip6_nxt));
762bad:
763 if (m)
764 m_freem(m);
765 state->m = NULL;
766 return error;
767}
768#endif /*INET6*/
2 * Copyright (c) 2002, 2003 Sam Leffler, Errno Consulting
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
26 * $FreeBSD: head/sys/netipsec/ipsec_output.c 151967 2005-11-02 13:46:32Z andre $
27 */
28
29/*
30 * IPsec output processing.
31 */
32#include "opt_inet.h"
33#include "opt_inet6.h"
34#include "opt_ipsec.h"
35
36#include <sys/param.h>
37#include <sys/systm.h>
38#include <sys/mbuf.h>
39#include <sys/domain.h>
40#include <sys/protosw.h>
41#include <sys/socket.h>
42#include <sys/errno.h>
43#include <sys/syslog.h>
44
45#include <net/if.h>
46#include <net/route.h>
47
48#include <netinet/in.h>
49#include <netinet/in_systm.h>
50#include <netinet/ip.h>
51#include <netinet/ip_var.h>
52#include <netinet/in_var.h>
53#include <netinet/ip_ecn.h>
54#ifdef INET6
55#include <netinet6/ip6_ecn.h>
56#endif
57
58#include <netinet/ip6.h>
59#ifdef INET6
60#include <netinet6/ip6_var.h>
61#endif
62#include <netinet/in_pcb.h>
63#ifdef INET6
64#include <netinet/icmp6.h>
65#endif
66
67#include <netipsec/ipsec.h>
68#ifdef INET6
69#include <netipsec/ipsec6.h>
70#endif
71#include <netipsec/ah_var.h>
72#include <netipsec/esp_var.h>
73#include <netipsec/ipcomp_var.h>
74
75#include <netipsec/xform.h>
76
77#include <netipsec/key.h>
78#include <netipsec/keydb.h>
79#include <netipsec/key_debug.h>
80
81#include <machine/in_cksum.h>
82
83int
84ipsec_process_done(struct mbuf *m, struct ipsecrequest *isr)
85{
86 struct tdb_ident *tdbi;
87 struct m_tag *mtag;
88 struct secasvar *sav;
89 struct secasindex *saidx;
90 int error;
91
92 IPSEC_SPLASSERT_SOFTNET(__func__);
93
94 IPSEC_ASSERT(m != NULL, ("null mbuf"));
95 IPSEC_ASSERT(isr != NULL, ("null ISR"));
96 sav = isr->sav;
97 IPSEC_ASSERT(sav != NULL, ("null SA"));
98 IPSEC_ASSERT(sav->sah != NULL, ("null SAH"));
99
100 saidx = &sav->sah->saidx;
101 switch (saidx->dst.sa.sa_family) {
102#ifdef INET
103 case AF_INET:
104 /* Fix the header length, for AH processing. */
105 mtod(m, struct ip *)->ip_len = htons(m->m_pkthdr.len);
106 break;
107#endif /* INET */
108#ifdef INET6
109 case AF_INET6:
110 /* Fix the header length, for AH processing. */
111 if (m->m_pkthdr.len < sizeof (struct ip6_hdr)) {
112 error = ENXIO;
113 goto bad;
114 }
115 if (m->m_pkthdr.len - sizeof (struct ip6_hdr) > IPV6_MAXPACKET) {
116 /* No jumbogram support. */
117 error = ENXIO; /*?*/
118 goto bad;
119 }
120 mtod(m, struct ip6_hdr *)->ip6_plen =
121 htons(m->m_pkthdr.len - sizeof(struct ip6_hdr));
122 break;
123#endif /* INET6 */
124 default:
125 DPRINTF(("%s: unknown protocol family %u\n", __func__,
126 saidx->dst.sa.sa_family));
127 error = ENXIO;
128 goto bad;
129 }
130
131 /*
132 * Add a record of what we've done or what needs to be done to the
133 * packet.
134 */
135 mtag = m_tag_get(PACKET_TAG_IPSEC_OUT_DONE,
136 sizeof(struct tdb_ident), M_NOWAIT);
137 if (mtag == NULL) {
138 DPRINTF(("%s: could not get packet tag\n", __func__));
139 error = ENOMEM;
140 goto bad;
141 }
142
143 tdbi = (struct tdb_ident *)(mtag + 1);
144 tdbi->dst = saidx->dst;
145 tdbi->proto = saidx->proto;
146 tdbi->spi = sav->spi;
147 m_tag_prepend(m, mtag);
148
149 /*
150 * If there's another (bundled) SA to apply, do so.
151 * Note that this puts a burden on the kernel stack size.
152 * If this is a problem we'll need to introduce a queue
153 * to set the packet on so we can unwind the stack before
154 * doing further processing.
155 */
156 if (isr->next) {
157 newipsecstat.ips_out_bundlesa++;
158 return ipsec4_process_packet(m, isr->next, 0, 0);
159 }
160 key_sa_recordxfer(sav, m); /* record data transfer */
161
162 /*
163 * We're done with IPsec processing, transmit the packet using the
164 * appropriate network protocol (IP or IPv6). SPD lookup will be
165 * performed again there.
166 */
167 switch (saidx->dst.sa.sa_family) {
168#ifdef INET
169 struct ip *ip;
170 case AF_INET:
171 ip = mtod(m, struct ip *);
172 ip->ip_len = ntohs(ip->ip_len);
173 ip->ip_off = ntohs(ip->ip_off);
174
175 return ip_output(m, NULL, NULL, IP_RAWOUTPUT, NULL, NULL);
176#endif /* INET */
177#ifdef INET6
178 case AF_INET6:
179 /*
180 * We don't need massage, IPv6 header fields are always in
181 * net endian.
182 */
183 return ip6_output(m, NULL, NULL, 0, NULL, NULL, NULL);
184#endif /* INET6 */
185 }
186 panic("ipsec_process_done");
187bad:
188 m_freem(m);
189 KEY_FREESAV(&sav);
190 return (error);
191}
192
193static struct ipsecrequest *
194ipsec_nextisr(
195 struct mbuf *m,
196 struct ipsecrequest *isr,
197 int af,
198 struct secasindex *saidx,
199 int *error
200)
201{
202#define IPSEC_OSTAT(x,y,z) (isr->saidx.proto == IPPROTO_ESP ? (x)++ : \
203 isr->saidx.proto == IPPROTO_AH ? (y)++ : (z)++)
204 struct secasvar *sav;
205
206 IPSEC_SPLASSERT_SOFTNET(__func__);
207 IPSECREQUEST_LOCK_ASSERT(isr);
208
209 IPSEC_ASSERT(af == AF_INET || af == AF_INET6,
210 ("invalid address family %u", af));
211again:
212 /*
213 * Craft SA index to search for proper SA. Note that
214 * we only fillin unspecified SA peers for transport
215 * mode; for tunnel mode they must already be filled in.
216 */
217 *saidx = isr->saidx;
218 if (isr->saidx.mode == IPSEC_MODE_TRANSPORT) {
219 /* Fillin unspecified SA peers only for transport mode */
220 if (af == AF_INET) {
221 struct sockaddr_in *sin;
222 struct ip *ip = mtod(m, struct ip *);
223
224 if (saidx->src.sa.sa_len == 0) {
225 sin = &saidx->src.sin;
226 sin->sin_len = sizeof(*sin);
227 sin->sin_family = AF_INET;
228 sin->sin_port = IPSEC_PORT_ANY;
229 sin->sin_addr = ip->ip_src;
230 }
231 if (saidx->dst.sa.sa_len == 0) {
232 sin = &saidx->dst.sin;
233 sin->sin_len = sizeof(*sin);
234 sin->sin_family = AF_INET;
235 sin->sin_port = IPSEC_PORT_ANY;
236 sin->sin_addr = ip->ip_dst;
237 }
238 } else {
239 struct sockaddr_in6 *sin6;
240 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
241
242 if (saidx->src.sin6.sin6_len == 0) {
243 sin6 = (struct sockaddr_in6 *)&saidx->src;
244 sin6->sin6_len = sizeof(*sin6);
245 sin6->sin6_family = AF_INET6;
246 sin6->sin6_port = IPSEC_PORT_ANY;
247 sin6->sin6_addr = ip6->ip6_src;
248 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) {
249 /* fix scope id for comparing SPD */
250 sin6->sin6_addr.s6_addr16[1] = 0;
251 sin6->sin6_scope_id =
252 ntohs(ip6->ip6_src.s6_addr16[1]);
253 }
254 }
255 if (saidx->dst.sin6.sin6_len == 0) {
256 sin6 = (struct sockaddr_in6 *)&saidx->dst;
257 sin6->sin6_len = sizeof(*sin6);
258 sin6->sin6_family = AF_INET6;
259 sin6->sin6_port = IPSEC_PORT_ANY;
260 sin6->sin6_addr = ip6->ip6_dst;
261 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) {
262 /* fix scope id for comparing SPD */
263 sin6->sin6_addr.s6_addr16[1] = 0;
264 sin6->sin6_scope_id =
265 ntohs(ip6->ip6_dst.s6_addr16[1]);
266 }
267 }
268 }
269 }
270
271 /*
272 * Lookup SA and validate it.
273 */
274 *error = key_checkrequest(isr, saidx);
275 if (*error != 0) {
276 /*
277 * IPsec processing is required, but no SA found.
278 * I assume that key_acquire() had been called
279 * to get/establish the SA. Here I discard
280 * this packet because it is responsibility for
281 * upper layer to retransmit the packet.
282 */
283 newipsecstat.ips_out_nosa++;
284 goto bad;
285 }
286 sav = isr->sav;
287 if (sav == NULL) { /* XXX valid return */
288 IPSEC_ASSERT(ipsec_get_reqlevel(isr) == IPSEC_LEVEL_USE,
289 ("no SA found, but required; level %u",
290 ipsec_get_reqlevel(isr)));
291 IPSECREQUEST_UNLOCK(isr);
292 isr = isr->next;
293 if (isr == NULL) {
294 /*XXXstatistic??*/
295 *error = EINVAL; /*XXX*/
296 return isr;
297 }
298 IPSECREQUEST_LOCK(isr);
299 goto again;
300 }
301
302 /*
303 * Check system global policy controls.
304 */
305 if ((isr->saidx.proto == IPPROTO_ESP && !esp_enable) ||
306 (isr->saidx.proto == IPPROTO_AH && !ah_enable) ||
307 (isr->saidx.proto == IPPROTO_IPCOMP && !ipcomp_enable)) {
308 DPRINTF(("%s: IPsec outbound packet dropped due"
309 " to policy (check your sysctls)\n", __func__));
310 IPSEC_OSTAT(espstat.esps_pdrops, ahstat.ahs_pdrops,
311 ipcompstat.ipcomps_pdrops);
312 *error = EHOSTUNREACH;
313 goto bad;
314 }
315
316 /*
317 * Sanity check the SA contents for the caller
318 * before they invoke the xform output method.
319 */
320 if (sav->tdb_xform == NULL) {
321 DPRINTF(("%s: no transform for SA\n", __func__));
322 IPSEC_OSTAT(espstat.esps_noxform, ahstat.ahs_noxform,
323 ipcompstat.ipcomps_noxform);
324 *error = EHOSTUNREACH;
325 goto bad;
326 }
327 return isr;
328bad:
329 IPSEC_ASSERT(*error != 0, ("error return w/ no error code"));
330 IPSECREQUEST_UNLOCK(isr);
331 return NULL;
332#undef IPSEC_OSTAT
333}
334
335#ifdef INET
336/*
337 * IPsec output logic for IPv4.
338 */
339int
340ipsec4_process_packet(
341 struct mbuf *m,
342 struct ipsecrequest *isr,
343 int flags,
344 int tunalready)
345{
346 struct secasindex saidx;
347 struct secasvar *sav;
348 struct ip *ip;
349 int error, i, off;
350
351 IPSEC_ASSERT(m != NULL, ("null mbuf"));
352 IPSEC_ASSERT(isr != NULL, ("null isr"));
353
354 IPSECREQUEST_LOCK(isr); /* insure SA contents don't change */
355
356 isr = ipsec_nextisr(m, isr, AF_INET, &saidx, &error);
357 if (isr == NULL)
358 goto bad;
359
360 sav = isr->sav;
361 if (!tunalready) {
362 union sockaddr_union *dst = &sav->sah->saidx.dst;
363 int setdf;
364
365 /*
366 * Collect IP_DF state from the outer header.
367 */
368 if (dst->sa.sa_family == AF_INET) {
369 if (m->m_len < sizeof (struct ip) &&
370 (m = m_pullup(m, sizeof (struct ip))) == NULL) {
371 error = ENOBUFS;
372 goto bad;
373 }
374 ip = mtod(m, struct ip *);
375 /* Honor system-wide control of how to handle IP_DF */
376 switch (ip4_ipsec_dfbit) {
377 case 0: /* clear in outer header */
378 case 1: /* set in outer header */
379 setdf = ip4_ipsec_dfbit;
380 break;
381 default: /* propagate to outer header */
382 setdf = ntohs(ip->ip_off & IP_DF);
383 break;
384 }
385 } else {
386 ip = NULL; /* keep compiler happy */
387 setdf = 0;
388 }
389 /* Do the appropriate encapsulation, if necessary */
390 if (isr->saidx.mode == IPSEC_MODE_TUNNEL || /* Tunnel requ'd */
391 dst->sa.sa_family != AF_INET || /* PF mismatch */
392#if 0
393 (sav->flags & SADB_X_SAFLAGS_TUNNEL) || /* Tunnel requ'd */
394 sav->tdb_xform->xf_type == XF_IP4 || /* ditto */
395#endif
396 (dst->sa.sa_family == AF_INET && /* Proxy */
397 dst->sin.sin_addr.s_addr != INADDR_ANY &&
398 dst->sin.sin_addr.s_addr != ip->ip_dst.s_addr)) {
399 struct mbuf *mp;
400
401 /* Fix IPv4 header checksum and length */
402 if (m->m_len < sizeof (struct ip) &&
403 (m = m_pullup(m, sizeof (struct ip))) == NULL) {
404 error = ENOBUFS;
405 goto bad;
406 }
407 ip = mtod(m, struct ip *);
408 ip->ip_len = htons(m->m_pkthdr.len);
409 ip->ip_sum = 0;
410#ifdef _IP_VHL
411 if (ip->ip_vhl == IP_VHL_BORING)
412 ip->ip_sum = in_cksum_hdr(ip);
413 else
414 ip->ip_sum = in_cksum(m,
415 _IP_VHL_HL(ip->ip_vhl) << 2);
416#else
417 ip->ip_sum = in_cksum(m, ip->ip_hl << 2);
418#endif
419
420 /* Encapsulate the packet */
421 error = ipip_output(m, isr, &mp, 0, 0);
422 if (mp == NULL && !error) {
423 /* Should never happen. */
424 DPRINTF(("%s: ipip_output returns no mbuf and "
425 "no error!", __func__));
426 error = EFAULT;
427 }
428 if (error) {
429 if (mp) {
430 /* XXX: Should never happen! */
431 m_freem(mp);
432 }
433 m = NULL; /* ipip_output() already freed it */
434 goto bad;
435 }
436 m = mp, mp = NULL;
437 /*
438 * ipip_output clears IP_DF in the new header. If
439 * we need to propagate IP_DF from the outer header,
440 * then we have to do it here.
441 *
442 * XXX shouldn't assume what ipip_output does.
443 */
444 if (dst->sa.sa_family == AF_INET && setdf) {
445 if (m->m_len < sizeof (struct ip) &&
446 (m = m_pullup(m, sizeof (struct ip))) == NULL) {
447 error = ENOBUFS;
448 goto bad;
449 }
450 ip = mtod(m, struct ip *);
451 ip->ip_off = ntohs(ip->ip_off);
452 ip->ip_off |= IP_DF;
453 ip->ip_off = htons(ip->ip_off);
454 }
455 }
456 }
457
458 /*
459 * Dispatch to the appropriate IPsec transform logic. The
460 * packet will be returned for transmission after crypto
461 * processing, etc. are completed. For encapsulation we
462 * bypass this call because of the explicit call done above
463 * (necessary to deal with IP_DF handling for IPv4).
464 *
465 * NB: m & sav are ``passed to caller'' who's reponsible for
466 * for reclaiming their resources.
467 */
468 if (sav->tdb_xform->xf_type != XF_IP4) {
469 ip = mtod(m, struct ip *);
470 i = ip->ip_hl << 2;
471 off = offsetof(struct ip, ip_p);
472 error = (*sav->tdb_xform->xf_output)(m, isr, NULL, i, off);
473 } else {
474 error = ipsec_process_done(m, isr);
475 }
476 IPSECREQUEST_UNLOCK(isr);
477 return error;
478bad:
479 if (isr)
480 IPSECREQUEST_UNLOCK(isr);
481 if (m)
482 m_freem(m);
483 return error;
484}
485#endif
486
487#ifdef INET6
488/*
489 * Chop IP6 header from the payload.
490 */
491static struct mbuf *
492ipsec6_splithdr(struct mbuf *m)
493{
494 struct mbuf *mh;
495 struct ip6_hdr *ip6;
496 int hlen;
497
498 IPSEC_ASSERT(m->m_len >= sizeof (struct ip6_hdr),
499 ("first mbuf too short, len %u", m->m_len));
500 ip6 = mtod(m, struct ip6_hdr *);
501 hlen = sizeof(struct ip6_hdr);
502 if (m->m_len > hlen) {
503 MGETHDR(mh, M_DONTWAIT, MT_DATA);
504 if (!mh) {
505 m_freem(m);
506 return NULL;
507 }
508 M_MOVE_PKTHDR(mh, m);
509 MH_ALIGN(mh, hlen);
510 m->m_len -= hlen;
511 m->m_data += hlen;
512 mh->m_next = m;
513 m = mh;
514 m->m_len = hlen;
515 bcopy((caddr_t)ip6, mtod(m, caddr_t), hlen);
516 } else if (m->m_len < hlen) {
517 m = m_pullup(m, hlen);
518 if (!m)
519 return NULL;
520 }
521 return m;
522}
523
524/*
525 * IPsec output logic for IPv6, transport mode.
526 */
527int
528ipsec6_output_trans(
529 struct ipsec_output_state *state,
530 u_char *nexthdrp,
531 struct mbuf *mprev,
532 struct secpolicy *sp,
533 int flags,
534 int *tun)
535{
536 struct ipsecrequest *isr;
537 struct secasindex saidx;
538 int error = 0;
539 struct mbuf *m;
540
541 IPSEC_ASSERT(state != NULL, ("null state"));
542 IPSEC_ASSERT(state->m != NULL, ("null m"));
543 IPSEC_ASSERT(nexthdrp != NULL, ("null nexthdrp"));
544 IPSEC_ASSERT(mprev != NULL, ("null mprev"));
545 IPSEC_ASSERT(sp != NULL, ("null sp"));
546 IPSEC_ASSERT(tun != NULL, ("null tun"));
547
548 KEYDEBUG(KEYDEBUG_IPSEC_DATA,
549 printf("%s: applyed SP\n", __func__);
550 kdebug_secpolicy(sp));
551
552 isr = sp->req;
553 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) {
554 /* the rest will be handled by ipsec6_output_tunnel() */
555 *tun = 1; /* need tunnel-mode processing */
556 return 0;
557 }
558
559 *tun = 0;
560 m = state->m;
561
562 isr = ipsec_nextisr(m, isr, AF_INET6, &saidx, &error);
563 if (isr == NULL) {
564#ifdef notdef
565 /* XXX should notification be done for all errors ? */
566 /*
567 * Notify the fact that the packet is discarded
568 * to ourselves. I believe this is better than
569 * just silently discarding. (jinmei@kame.net)
570 * XXX: should we restrict the error to TCP packets?
571 * XXX: should we directly notify sockets via
572 * pfctlinputs?
573 */
574 icmp6_error(m, ICMP6_DST_UNREACH,
575 ICMP6_DST_UNREACH_ADMIN, 0);
576 m = NULL; /* NB: icmp6_error frees mbuf */
577#endif
578 goto bad;
579 }
580
581 return (*isr->sav->tdb_xform->xf_output)(m, isr, NULL,
582 sizeof (struct ip6_hdr),
583 offsetof(struct ip6_hdr, ip6_nxt));
584bad:
585 if (m)
586 m_freem(m);
587 state->m = NULL;
588 return error;
589}
590
591static int
592ipsec6_encapsulate(struct mbuf *m, struct secasvar *sav)
593{
594 struct ip6_hdr *oip6;
595 struct ip6_hdr *ip6;
596 size_t plen;
597
598 /* can't tunnel between different AFs */
599 if (sav->sah->saidx.src.sa.sa_family != AF_INET6 ||
600 sav->sah->saidx.dst.sa.sa_family != AF_INET6) {
601 m_freem(m);
602 return EINVAL;
603 }
604 IPSEC_ASSERT(m->m_len != sizeof (struct ip6_hdr),
605 ("mbuf wrong size; len %u", m->m_len));
606
607
608 /*
609 * grow the mbuf to accomodate the new IPv6 header.
610 */
611 plen = m->m_pkthdr.len;
612 if (M_LEADINGSPACE(m->m_next) < sizeof(struct ip6_hdr)) {
613 struct mbuf *n;
614 MGET(n, M_DONTWAIT, MT_DATA);
615 if (!n) {
616 m_freem(m);
617 return ENOBUFS;
618 }
619 n->m_len = sizeof(struct ip6_hdr);
620 n->m_next = m->m_next;
621 m->m_next = n;
622 m->m_pkthdr.len += sizeof(struct ip6_hdr);
623 oip6 = mtod(n, struct ip6_hdr *);
624 } else {
625 m->m_next->m_len += sizeof(struct ip6_hdr);
626 m->m_next->m_data -= sizeof(struct ip6_hdr);
627 m->m_pkthdr.len += sizeof(struct ip6_hdr);
628 oip6 = mtod(m->m_next, struct ip6_hdr *);
629 }
630 ip6 = mtod(m, struct ip6_hdr *);
631 bcopy((caddr_t)ip6, (caddr_t)oip6, sizeof(struct ip6_hdr));
632
633 /* Fake link-local scope-class addresses */
634 if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_src))
635 oip6->ip6_src.s6_addr16[1] = 0;
636 if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_dst))
637 oip6->ip6_dst.s6_addr16[1] = 0;
638
639 /* construct new IPv6 header. see RFC 2401 5.1.2.2 */
640 /* ECN consideration. */
641 ip6_ecn_ingress(ip6_ipsec_ecn, &ip6->ip6_flow, &oip6->ip6_flow);
642 if (plen < IPV6_MAXPACKET - sizeof(struct ip6_hdr))
643 ip6->ip6_plen = htons(plen);
644 else {
645 /* ip6->ip6_plen will be updated in ip6_output() */
646 }
647 ip6->ip6_nxt = IPPROTO_IPV6;
648 sav->sah->saidx.src.sin6.sin6_addr = ip6->ip6_src;
649 sav->sah->saidx.dst.sin6.sin6_addr = ip6->ip6_dst;
650 ip6->ip6_hlim = IPV6_DEFHLIM;
651
652 /* XXX Should ip6_src be updated later ? */
653
654 return 0;
655}
656
657/*
658 * IPsec output logic for IPv6, tunnel mode.
659 */
660int
661ipsec6_output_tunnel(struct ipsec_output_state *state, struct secpolicy *sp, int flags)
662{
663 struct ip6_hdr *ip6;
664 struct ipsecrequest *isr;
665 struct secasindex saidx;
666 int error;
667 struct sockaddr_in6* dst6;
668 struct mbuf *m;
669
670 IPSEC_ASSERT(state != NULL, ("null state"));
671 IPSEC_ASSERT(state->m != NULL, ("null m"));
672 IPSEC_ASSERT(sp != NULL, ("null sp"));
673
674 KEYDEBUG(KEYDEBUG_IPSEC_DATA,
675 printf("%s: applyed SP\n", __func__);
676 kdebug_secpolicy(sp));
677
678 m = state->m;
679 /*
680 * transport mode ipsec (before the 1st tunnel mode) is already
681 * processed by ipsec6_output_trans().
682 */
683 for (isr = sp->req; isr; isr = isr->next) {
684 if (isr->saidx.mode == IPSEC_MODE_TUNNEL)
685 break;
686 }
687 isr = ipsec_nextisr(m, isr, AF_INET6, &saidx, &error);
688 if (isr == NULL)
689 goto bad;
690
691 /*
692 * There may be the case that SA status will be changed when
693 * we are refering to one. So calling splsoftnet().
694 */
695 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) {
696 /*
697 * build IPsec tunnel.
698 */
699 /* XXX should be processed with other familiy */
700 if (isr->sav->sah->saidx.src.sa.sa_family != AF_INET6) {
701 ipseclog((LOG_ERR, "%s: family mismatched between "
702 "inner and outer, spi=%u\n", __func__,
703 ntohl(isr->sav->spi)));
704 newipsecstat.ips_out_inval++;
705 error = EAFNOSUPPORT;
706 goto bad;
707 }
708
709 m = ipsec6_splithdr(m);
710 if (!m) {
711 newipsecstat.ips_out_nomem++;
712 error = ENOMEM;
713 goto bad;
714 }
715 error = ipsec6_encapsulate(m, isr->sav);
716 if (error) {
717 m = NULL;
718 goto bad;
719 }
720 ip6 = mtod(m, struct ip6_hdr *);
721
722 state->ro = &isr->sav->sah->sa_route;
723 state->dst = (struct sockaddr *)&state->ro->ro_dst;
724 dst6 = (struct sockaddr_in6 *)state->dst;
725 if (state->ro->ro_rt
726 && ((state->ro->ro_rt->rt_flags & RTF_UP) == 0
727 || !IN6_ARE_ADDR_EQUAL(&dst6->sin6_addr, &ip6->ip6_dst))) {
728 RTFREE(state->ro->ro_rt);
729 state->ro->ro_rt = NULL;
730 }
731 if (state->ro->ro_rt == 0) {
732 bzero(dst6, sizeof(*dst6));
733 dst6->sin6_family = AF_INET6;
734 dst6->sin6_len = sizeof(*dst6);
735 dst6->sin6_addr = ip6->ip6_dst;
736 rtalloc(state->ro);
737 }
738 if (state->ro->ro_rt == 0) {
739 ip6stat.ip6s_noroute++;
740 newipsecstat.ips_out_noroute++;
741 error = EHOSTUNREACH;
742 goto bad;
743 }
744
745 /* adjust state->dst if tunnel endpoint is offlink */
746 if (state->ro->ro_rt->rt_flags & RTF_GATEWAY) {
747 state->dst = (struct sockaddr *)state->ro->ro_rt->rt_gateway;
748 dst6 = (struct sockaddr_in6 *)state->dst;
749 }
750 }
751
752 m = ipsec6_splithdr(m);
753 if (!m) {
754 newipsecstat.ips_out_nomem++;
755 error = ENOMEM;
756 goto bad;
757 }
758 ip6 = mtod(m, struct ip6_hdr *);
759 return (*isr->sav->tdb_xform->xf_output)(m, isr, NULL,
760 sizeof (struct ip6_hdr),
761 offsetof(struct ip6_hdr, ip6_nxt));
762bad:
763 if (m)
764 m_freem(m);
765 state->m = NULL;
766 return error;
767}
768#endif /*INET6*/