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: releng/8.1/sys/netipsec/ipsec_output.c 199583 2009-11-20 15:27:52Z jhb $
27 */
28
29 /*
30 * IPsec output processing.
31 */
32 #include "opt_inet.h"
33 #include "opt_inet6.h"
34 #include "opt_ipsec.h"
35 #include "opt_enc.h"
36
37 #include <sys/param.h>
38 #include <sys/systm.h>
39 #include <sys/mbuf.h>
40 #include <sys/domain.h>
41 #include <sys/protosw.h>
42 #include <sys/socket.h>
43 #include <sys/errno.h>
44 #include <sys/syslog.h>
45
46 #include <net/if.h>
47 #include <net/pfil.h>
48 #include <net/route.h>
49 #include <net/vnet.h>
50
51 #include <netinet/in.h>
52 #include <netinet/in_systm.h>
53 #include <netinet/ip.h>
54 #include <netinet/ip_var.h>
55 #include <netinet/in_var.h>
56 #include <netinet/ip_ecn.h>
57 #ifdef INET6
58 #include <netinet6/ip6_ecn.h>
59 #endif
60
61 #include <netinet/ip6.h>
62 #ifdef INET6
63 #include <netinet6/ip6_var.h>
64 #endif
65 #include <netinet/in_pcb.h>
66 #ifdef INET6
67 #include <netinet/icmp6.h>
68 #endif
69
70 #include <netipsec/ipsec.h>
71 #ifdef INET6
72 #include <netipsec/ipsec6.h>
73 #endif
74 #include <netipsec/ah_var.h>
75 #include <netipsec/esp_var.h>
76 #include <netipsec/ipcomp_var.h>
77
78 #include <netipsec/xform.h>
79
80 #include <netipsec/key.h>
81 #include <netipsec/keydb.h>
82 #include <netipsec/key_debug.h>
83
84 #include <machine/in_cksum.h>
85
86 #ifdef IPSEC_NAT_T
87 #include <netinet/udp.h>
88 #endif
89
90 #ifdef DEV_ENC
91 #include <net/if_enc.h>
92 #endif
93
94
95 int
96 ipsec_process_done(struct mbuf *m, struct ipsecrequest *isr)
97 {
98 struct tdb_ident *tdbi;
99 struct m_tag *mtag;
100 struct secasvar *sav;
101 struct secasindex *saidx;
102 int error;
103
104 IPSEC_ASSERT(m != NULL, ("null mbuf"));
105 IPSEC_ASSERT(isr != NULL, ("null ISR"));
106 sav = isr->sav;
107 IPSEC_ASSERT(sav != NULL, ("null SA"));
108 IPSEC_ASSERT(sav->sah != NULL, ("null SAH"));
109
110 saidx = &sav->sah->saidx;
111 switch (saidx->dst.sa.sa_family) {
112 #ifdef INET
113 case AF_INET:
114 /* Fix the header length, for AH processing. */
115 mtod(m, struct ip *)->ip_len = htons(m->m_pkthdr.len);
116 break;
117 #endif /* INET */
118 #ifdef INET6
119 case AF_INET6:
120 /* Fix the header length, for AH processing. */
121 if (m->m_pkthdr.len < sizeof (struct ip6_hdr)) {
122 error = ENXIO;
123 goto bad;
124 }
125 if (m->m_pkthdr.len - sizeof (struct ip6_hdr) > IPV6_MAXPACKET) {
126 /* No jumbogram support. */
127 error = ENXIO; /*?*/
128 goto bad;
129 }
130 mtod(m, struct ip6_hdr *)->ip6_plen =
131 htons(m->m_pkthdr.len - sizeof(struct ip6_hdr));
132 break;
133 #endif /* INET6 */
134 default:
135 DPRINTF(("%s: unknown protocol family %u\n", __func__,
136 saidx->dst.sa.sa_family));
137 error = ENXIO;
138 goto bad;
139 }
140
141 /*
142 * Add a record of what we've done or what needs to be done to the
143 * packet.
144 */
145 mtag = m_tag_get(PACKET_TAG_IPSEC_OUT_DONE,
146 sizeof(struct tdb_ident), M_NOWAIT);
147 if (mtag == NULL) {
148 DPRINTF(("%s: could not get packet tag\n", __func__));
149 error = ENOMEM;
150 goto bad;
151 }
152
153 tdbi = (struct tdb_ident *)(mtag + 1);
154 tdbi->dst = saidx->dst;
155 tdbi->proto = saidx->proto;
156 tdbi->spi = sav->spi;
157 m_tag_prepend(m, mtag);
158
159 /*
160 * If there's another (bundled) SA to apply, do so.
161 * Note that this puts a burden on the kernel stack size.
162 * If this is a problem we'll need to introduce a queue
163 * to set the packet on so we can unwind the stack before
164 * doing further processing.
165 */
166 if (isr->next) {
167 V_ipsec4stat.ips_out_bundlesa++;
168 return ipsec4_process_packet(m, isr->next, 0, 0);
169 }
170 key_sa_recordxfer(sav, m); /* record data transfer */
171
172 /*
173 * We're done with IPsec processing, transmit the packet using the
174 * appropriate network protocol (IP or IPv6). SPD lookup will be
175 * performed again there.
176 */
177 switch (saidx->dst.sa.sa_family) {
178 #ifdef INET
179 struct ip *ip;
180 case AF_INET:
181 ip = mtod(m, struct ip *);
182 ip->ip_len = ntohs(ip->ip_len);
183 ip->ip_off = ntohs(ip->ip_off);
184
185 #ifdef IPSEC_NAT_T
186 /*
187 * If NAT-T is enabled, now that all IPsec processing is done
188 * insert UDP encapsulation header after IP header.
189 */
190 if (sav->natt_type) {
191 #ifdef _IP_VHL
192 const int hlen = IP_VHL_HL(ip->ip_vhl);
193 #else
194 const int hlen = (ip->ip_hl << 2);
195 #endif
196 int size, off;
197 struct mbuf *mi;
198 struct udphdr *udp;
199
200 size = sizeof(struct udphdr);
201 if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE) {
202 /*
203 * draft-ietf-ipsec-nat-t-ike-0[01].txt and
204 * draft-ietf-ipsec-udp-encaps-(00/)01.txt,
205 * ignoring possible AH mode
206 * non-IKE marker + non-ESP marker
207 * from draft-ietf-ipsec-udp-encaps-00.txt.
208 */
209 size += sizeof(u_int64_t);
210 }
211 mi = m_makespace(m, hlen, size, &off);
212 if (mi == NULL) {
213 DPRINTF(("%s: m_makespace for udphdr failed\n",
214 __func__));
215 error = ENOBUFS;
216 goto bad;
217 }
218
219 udp = (struct udphdr *)(mtod(mi, caddr_t) + off);
220 if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE)
221 udp->uh_sport = htons(UDP_ENCAP_ESPINUDP_PORT);
222 else
223 udp->uh_sport =
224 KEY_PORTFROMSADDR(&sav->sah->saidx.src);
225 udp->uh_dport = KEY_PORTFROMSADDR(&sav->sah->saidx.dst);
226 udp->uh_sum = 0;
227 udp->uh_ulen = htons(m->m_pkthdr.len - hlen);
228 ip->ip_len = m->m_pkthdr.len;
229 ip->ip_p = IPPROTO_UDP;
230
231 if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE)
232 *(u_int64_t *)(udp + 1) = 0;
233 }
234 #endif /* IPSEC_NAT_T */
235
236 return ip_output(m, NULL, NULL, IP_RAWOUTPUT, NULL, NULL);
237 #endif /* INET */
238 #ifdef INET6
239 case AF_INET6:
240 /*
241 * We don't need massage, IPv6 header fields are always in
242 * net endian.
243 */
244 return ip6_output(m, NULL, NULL, 0, NULL, NULL, NULL);
245 #endif /* INET6 */
246 }
247 panic("ipsec_process_done");
248 bad:
249 m_freem(m);
250 KEY_FREESAV(&sav);
251 return (error);
252 }
253
254 static struct ipsecrequest *
255 ipsec_nextisr(
256 struct mbuf *m,
257 struct ipsecrequest *isr,
258 int af,
259 struct secasindex *saidx,
260 int *error
261 )
262 {
263 #define IPSEC_OSTAT(x,y,z) (isr->saidx.proto == IPPROTO_ESP ? (x)++ : \
264 isr->saidx.proto == IPPROTO_AH ? (y)++ : (z)++)
265 struct secasvar *sav;
266
267 IPSECREQUEST_LOCK_ASSERT(isr);
268
269 IPSEC_ASSERT(af == AF_INET || af == AF_INET6,
270 ("invalid address family %u", af));
271 again:
272 /*
273 * Craft SA index to search for proper SA. Note that
274 * we only fillin unspecified SA peers for transport
275 * mode; for tunnel mode they must already be filled in.
276 */
277 *saidx = isr->saidx;
278 if (isr->saidx.mode == IPSEC_MODE_TRANSPORT) {
279 /* Fillin unspecified SA peers only for transport mode */
280 if (af == AF_INET) {
281 struct sockaddr_in *sin;
282 struct ip *ip = mtod(m, struct ip *);
283
284 if (saidx->src.sa.sa_len == 0) {
285 sin = &saidx->src.sin;
286 sin->sin_len = sizeof(*sin);
287 sin->sin_family = AF_INET;
288 sin->sin_port = IPSEC_PORT_ANY;
289 sin->sin_addr = ip->ip_src;
290 }
291 if (saidx->dst.sa.sa_len == 0) {
292 sin = &saidx->dst.sin;
293 sin->sin_len = sizeof(*sin);
294 sin->sin_family = AF_INET;
295 sin->sin_port = IPSEC_PORT_ANY;
296 sin->sin_addr = ip->ip_dst;
297 }
298 } else {
299 struct sockaddr_in6 *sin6;
300 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
301
302 if (saidx->src.sin6.sin6_len == 0) {
303 sin6 = (struct sockaddr_in6 *)&saidx->src;
304 sin6->sin6_len = sizeof(*sin6);
305 sin6->sin6_family = AF_INET6;
306 sin6->sin6_port = IPSEC_PORT_ANY;
307 sin6->sin6_addr = ip6->ip6_src;
308 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) {
309 /* fix scope id for comparing SPD */
310 sin6->sin6_addr.s6_addr16[1] = 0;
311 sin6->sin6_scope_id =
312 ntohs(ip6->ip6_src.s6_addr16[1]);
313 }
314 }
315 if (saidx->dst.sin6.sin6_len == 0) {
316 sin6 = (struct sockaddr_in6 *)&saidx->dst;
317 sin6->sin6_len = sizeof(*sin6);
318 sin6->sin6_family = AF_INET6;
319 sin6->sin6_port = IPSEC_PORT_ANY;
320 sin6->sin6_addr = ip6->ip6_dst;
321 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) {
322 /* fix scope id for comparing SPD */
323 sin6->sin6_addr.s6_addr16[1] = 0;
324 sin6->sin6_scope_id =
325 ntohs(ip6->ip6_dst.s6_addr16[1]);
326 }
327 }
328 }
329 }
330
331 /*
332 * Lookup SA and validate it.
333 */
334 *error = key_checkrequest(isr, saidx);
335 if (*error != 0) {
336 /*
337 * IPsec processing is required, but no SA found.
338 * I assume that key_acquire() had been called
339 * to get/establish the SA. Here I discard
340 * this packet because it is responsibility for
341 * upper layer to retransmit the packet.
342 */
343 V_ipsec4stat.ips_out_nosa++;
344 goto bad;
345 }
346 sav = isr->sav;
347 if (sav == NULL) {
348 IPSEC_ASSERT(ipsec_get_reqlevel(isr) == IPSEC_LEVEL_USE,
349 ("no SA found, but required; level %u",
350 ipsec_get_reqlevel(isr)));
351 IPSECREQUEST_UNLOCK(isr);
352 isr = isr->next;
353 /*
354 * If isr is NULL, we found a 'use' policy w/o SA.
355 * Return w/o error and w/o isr so we can drop out
356 * and continue w/o IPsec processing.
357 */
358 if (isr == NULL)
359 return isr;
360 IPSECREQUEST_LOCK(isr);
361 goto again;
362 }
363
364 /*
365 * Check system global policy controls.
366 */
367 if ((isr->saidx.proto == IPPROTO_ESP && !V_esp_enable) ||
368 (isr->saidx.proto == IPPROTO_AH && !V_ah_enable) ||
369 (isr->saidx.proto == IPPROTO_IPCOMP && !V_ipcomp_enable)) {
370 DPRINTF(("%s: IPsec outbound packet dropped due"
371 " to policy (check your sysctls)\n", __func__));
372 IPSEC_OSTAT(V_espstat.esps_pdrops, V_ahstat.ahs_pdrops,
373 V_ipcompstat.ipcomps_pdrops);
374 *error = EHOSTUNREACH;
375 goto bad;
376 }
377
378 /*
379 * Sanity check the SA contents for the caller
380 * before they invoke the xform output method.
381 */
382 if (sav->tdb_xform == NULL) {
383 DPRINTF(("%s: no transform for SA\n", __func__));
384 IPSEC_OSTAT(V_espstat.esps_noxform, V_ahstat.ahs_noxform,
385 V_ipcompstat.ipcomps_noxform);
386 *error = EHOSTUNREACH;
387 goto bad;
388 }
389 return isr;
390 bad:
391 IPSEC_ASSERT(*error != 0, ("error return w/ no error code"));
392 IPSECREQUEST_UNLOCK(isr);
393 return NULL;
394 #undef IPSEC_OSTAT
395 }
396
397 #ifdef INET
398 /*
399 * IPsec output logic for IPv4.
400 */
401 int
402 ipsec4_process_packet(
403 struct mbuf *m,
404 struct ipsecrequest *isr,
405 int flags,
406 int tunalready)
407 {
408 struct secasindex saidx;
409 struct secasvar *sav;
410 struct ip *ip;
411 int error, i, off;
412
413 IPSEC_ASSERT(m != NULL, ("null mbuf"));
414 IPSEC_ASSERT(isr != NULL, ("null isr"));
415
416 IPSECREQUEST_LOCK(isr); /* insure SA contents don't change */
417
418 isr = ipsec_nextisr(m, isr, AF_INET, &saidx, &error);
419 if (isr == NULL) {
420 if (error != 0)
421 goto bad;
422 return EJUSTRETURN;
423 }
424
425 sav = isr->sav;
426
427 #ifdef DEV_ENC
428 encif->if_opackets++;
429 encif->if_obytes += m->m_pkthdr.len;
430
431 /* pass the mbuf to enc0 for bpf processing */
432 ipsec_bpf(m, sav, AF_INET, ENC_OUT|ENC_BEFORE);
433 /* pass the mbuf to enc0 for packet filtering */
434 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_BEFORE)) != 0)
435 goto bad;
436 #endif
437
438 if (!tunalready) {
439 union sockaddr_union *dst = &sav->sah->saidx.dst;
440 int setdf;
441
442 /*
443 * Collect IP_DF state from the outer header.
444 */
445 if (dst->sa.sa_family == AF_INET) {
446 if (m->m_len < sizeof (struct ip) &&
447 (m = m_pullup(m, sizeof (struct ip))) == NULL) {
448 error = ENOBUFS;
449 goto bad;
450 }
451 ip = mtod(m, struct ip *);
452 /* Honor system-wide control of how to handle IP_DF */
453 switch (V_ip4_ipsec_dfbit) {
454 case 0: /* clear in outer header */
455 case 1: /* set in outer header */
456 setdf = V_ip4_ipsec_dfbit;
457 break;
458 default: /* propagate to outer header */
459 setdf = ntohs(ip->ip_off & IP_DF);
460 break;
461 }
462 } else {
463 ip = NULL; /* keep compiler happy */
464 setdf = 0;
465 }
466 /* Do the appropriate encapsulation, if necessary */
467 if (isr->saidx.mode == IPSEC_MODE_TUNNEL || /* Tunnel requ'd */
468 dst->sa.sa_family != AF_INET || /* PF mismatch */
469 #if 0
470 (sav->flags & SADB_X_SAFLAGS_TUNNEL) || /* Tunnel requ'd */
471 sav->tdb_xform->xf_type == XF_IP4 || /* ditto */
472 #endif
473 (dst->sa.sa_family == AF_INET && /* Proxy */
474 dst->sin.sin_addr.s_addr != INADDR_ANY &&
475 dst->sin.sin_addr.s_addr != ip->ip_dst.s_addr)) {
476 struct mbuf *mp;
477
478 /* Fix IPv4 header checksum and length */
479 if (m->m_len < sizeof (struct ip) &&
480 (m = m_pullup(m, sizeof (struct ip))) == NULL) {
481 error = ENOBUFS;
482 goto bad;
483 }
484 ip = mtod(m, struct ip *);
485 ip->ip_len = htons(m->m_pkthdr.len);
486 ip->ip_sum = 0;
487 #ifdef _IP_VHL
488 if (ip->ip_vhl == IP_VHL_BORING)
489 ip->ip_sum = in_cksum_hdr(ip);
490 else
491 ip->ip_sum = in_cksum(m,
492 _IP_VHL_HL(ip->ip_vhl) << 2);
493 #else
494 ip->ip_sum = in_cksum(m, ip->ip_hl << 2);
495 #endif
496
497 /* Encapsulate the packet */
498 error = ipip_output(m, isr, &mp, 0, 0);
499 if (mp == NULL && !error) {
500 /* Should never happen. */
501 DPRINTF(("%s: ipip_output returns no mbuf and "
502 "no error!", __func__));
503 error = EFAULT;
504 }
505 if (error) {
506 if (mp) {
507 /* XXX: Should never happen! */
508 m_freem(mp);
509 }
510 m = NULL; /* ipip_output() already freed it */
511 goto bad;
512 }
513 m = mp, mp = NULL;
514 /*
515 * ipip_output clears IP_DF in the new header. If
516 * we need to propagate IP_DF from the outer header,
517 * then we have to do it here.
518 *
519 * XXX shouldn't assume what ipip_output does.
520 */
521 if (dst->sa.sa_family == AF_INET && setdf) {
522 if (m->m_len < sizeof (struct ip) &&
523 (m = m_pullup(m, sizeof (struct ip))) == NULL) {
524 error = ENOBUFS;
525 goto bad;
526 }
527 ip = mtod(m, struct ip *);
528 ip->ip_off = ntohs(ip->ip_off);
529 ip->ip_off |= IP_DF;
530 ip->ip_off = htons(ip->ip_off);
531 }
532 }
533 }
534
535 #ifdef DEV_ENC
536 /* pass the mbuf to enc0 for bpf processing */
537 ipsec_bpf(m, sav, AF_INET, ENC_OUT|ENC_AFTER);
538 /* pass the mbuf to enc0 for packet filtering */
539 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_AFTER)) != 0)
540 goto bad;
541 #endif
542
543 /*
544 * Dispatch to the appropriate IPsec transform logic. The
545 * packet will be returned for transmission after crypto
546 * processing, etc. are completed. For encapsulation we
547 * bypass this call because of the explicit call done above
548 * (necessary to deal with IP_DF handling for IPv4).
549 *
550 * NB: m & sav are ``passed to caller'' who's reponsible for
551 * for reclaiming their resources.
552 */
553 if (sav->tdb_xform->xf_type != XF_IP4) {
554 ip = mtod(m, struct ip *);
555 i = ip->ip_hl << 2;
556 off = offsetof(struct ip, ip_p);
557 error = (*sav->tdb_xform->xf_output)(m, isr, NULL, i, off);
558 } else {
559 error = ipsec_process_done(m, isr);
560 }
561 IPSECREQUEST_UNLOCK(isr);
562 return error;
563 bad:
564 if (isr)
565 IPSECREQUEST_UNLOCK(isr);
566 if (m)
567 m_freem(m);
568 return error;
569 }
570 #endif
571
572 #ifdef INET6
573 /*
574 * Chop IP6 header from the payload.
575 */
576 static struct mbuf *
577 ipsec6_splithdr(struct mbuf *m)
578 {
579 struct mbuf *mh;
580 struct ip6_hdr *ip6;
581 int hlen;
582
583 IPSEC_ASSERT(m->m_len >= sizeof (struct ip6_hdr),
584 ("first mbuf too short, len %u", m->m_len));
585 ip6 = mtod(m, struct ip6_hdr *);
586 hlen = sizeof(struct ip6_hdr);
587 if (m->m_len > hlen) {
588 MGETHDR(mh, M_DONTWAIT, MT_DATA);
589 if (!mh) {
590 m_freem(m);
591 return NULL;
592 }
593 M_MOVE_PKTHDR(mh, m);
594 MH_ALIGN(mh, hlen);
595 m->m_len -= hlen;
596 m->m_data += hlen;
597 mh->m_next = m;
598 m = mh;
599 m->m_len = hlen;
600 bcopy((caddr_t)ip6, mtod(m, caddr_t), hlen);
601 } else if (m->m_len < hlen) {
602 m = m_pullup(m, hlen);
603 if (!m)
604 return NULL;
605 }
606 return m;
607 }
608
609 /*
610 * IPsec output logic for IPv6, transport mode.
611 */
612 int
613 ipsec6_output_trans(
614 struct ipsec_output_state *state,
615 u_char *nexthdrp,
616 struct mbuf *mprev,
617 struct secpolicy *sp,
618 int flags,
619 int *tun)
620 {
621 struct ipsecrequest *isr;
622 struct secasindex saidx;
623 int error = 0;
624 struct mbuf *m;
625
626 IPSEC_ASSERT(state != NULL, ("null state"));
627 IPSEC_ASSERT(state->m != NULL, ("null m"));
628 IPSEC_ASSERT(nexthdrp != NULL, ("null nexthdrp"));
629 IPSEC_ASSERT(mprev != NULL, ("null mprev"));
630 IPSEC_ASSERT(sp != NULL, ("null sp"));
631 IPSEC_ASSERT(tun != NULL, ("null tun"));
632
633 KEYDEBUG(KEYDEBUG_IPSEC_DATA,
634 printf("%s: applied SP\n", __func__);
635 kdebug_secpolicy(sp));
636
637 isr = sp->req;
638 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) {
639 /* the rest will be handled by ipsec6_output_tunnel() */
640 *tun = 1; /* need tunnel-mode processing */
641 return 0;
642 }
643
644 *tun = 0;
645 m = state->m;
646
647 IPSECREQUEST_LOCK(isr); /* insure SA contents don't change */
648 isr = ipsec_nextisr(m, isr, AF_INET6, &saidx, &error);
649 if (isr == NULL) {
650 if (error != 0) {
651 #ifdef notdef
652 /* XXX should notification be done for all errors ? */
653 /*
654 * Notify the fact that the packet is discarded
655 * to ourselves. I believe this is better than
656 * just silently discarding. (jinmei@kame.net)
657 * XXX: should we restrict the error to TCP packets?
658 * XXX: should we directly notify sockets via
659 * pfctlinputs?
660 */
661 icmp6_error(m, ICMP6_DST_UNREACH,
662 ICMP6_DST_UNREACH_ADMIN, 0);
663 m = NULL; /* NB: icmp6_error frees mbuf */
664 #endif
665 goto bad;
666 }
667 return EJUSTRETURN;
668 }
669
670 error = (*isr->sav->tdb_xform->xf_output)(m, isr, NULL,
671 sizeof (struct ip6_hdr),
672 offsetof(struct ip6_hdr,
673 ip6_nxt));
674 IPSECREQUEST_UNLOCK(isr);
675 return error;
676 bad:
677 if (isr)
678 IPSECREQUEST_UNLOCK(isr);
679 if (m)
680 m_freem(m);
681 state->m = NULL;
682 return error;
683 }
684
685 static int
686 ipsec6_encapsulate(struct mbuf *m, struct secasvar *sav)
687 {
688 struct ip6_hdr *oip6;
689 struct ip6_hdr *ip6;
690 size_t plen;
691
692 /* can't tunnel between different AFs */
693 if (sav->sah->saidx.src.sa.sa_family != AF_INET6 ||
694 sav->sah->saidx.dst.sa.sa_family != AF_INET6) {
695 m_freem(m);
696 return EINVAL;
697 }
698 IPSEC_ASSERT(m->m_len == sizeof (struct ip6_hdr),
699 ("mbuf wrong size; len %u", m->m_len));
700
701
702 /*
703 * grow the mbuf to accomodate the new IPv6 header.
704 */
705 plen = m->m_pkthdr.len;
706 if (M_LEADINGSPACE(m->m_next) < sizeof(struct ip6_hdr)) {
707 struct mbuf *n;
708 MGET(n, M_DONTWAIT, MT_DATA);
709 if (!n) {
710 m_freem(m);
711 return ENOBUFS;
712 }
713 n->m_len = sizeof(struct ip6_hdr);
714 n->m_next = m->m_next;
715 m->m_next = n;
716 m->m_pkthdr.len += sizeof(struct ip6_hdr);
717 oip6 = mtod(n, struct ip6_hdr *);
718 } else {
719 m->m_next->m_len += sizeof(struct ip6_hdr);
720 m->m_next->m_data -= sizeof(struct ip6_hdr);
721 m->m_pkthdr.len += sizeof(struct ip6_hdr);
722 oip6 = mtod(m->m_next, struct ip6_hdr *);
723 }
724 ip6 = mtod(m, struct ip6_hdr *);
725 bcopy((caddr_t)ip6, (caddr_t)oip6, sizeof(struct ip6_hdr));
726
727 /* Fake link-local scope-class addresses */
728 if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_src))
729 oip6->ip6_src.s6_addr16[1] = 0;
730 if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_dst))
731 oip6->ip6_dst.s6_addr16[1] = 0;
732
733 /* construct new IPv6 header. see RFC 2401 5.1.2.2 */
734 /* ECN consideration. */
735 ip6_ecn_ingress(V_ip6_ipsec_ecn, &ip6->ip6_flow, &oip6->ip6_flow);
736 if (plen < IPV6_MAXPACKET - sizeof(struct ip6_hdr))
737 ip6->ip6_plen = htons(plen);
738 else {
739 /* ip6->ip6_plen will be updated in ip6_output() */
740 }
741 ip6->ip6_nxt = IPPROTO_IPV6;
742 ip6->ip6_src = sav->sah->saidx.src.sin6.sin6_addr;
743 ip6->ip6_dst = sav->sah->saidx.dst.sin6.sin6_addr;
744 ip6->ip6_hlim = IPV6_DEFHLIM;
745
746 /* XXX Should ip6_src be updated later ? */
747
748 return 0;
749 }
750
751 /*
752 * IPsec output logic for IPv6, tunnel mode.
753 */
754 int
755 ipsec6_output_tunnel(struct ipsec_output_state *state, struct secpolicy *sp, int flags)
756 {
757 struct ip6_hdr *ip6;
758 struct ipsecrequest *isr;
759 struct secasindex saidx;
760 int error;
761 struct sockaddr_in6* dst6;
762 struct mbuf *m;
763
764 IPSEC_ASSERT(state != NULL, ("null state"));
765 IPSEC_ASSERT(state->m != NULL, ("null m"));
766 IPSEC_ASSERT(sp != NULL, ("null sp"));
767
768 KEYDEBUG(KEYDEBUG_IPSEC_DATA,
769 printf("%s: applied SP\n", __func__);
770 kdebug_secpolicy(sp));
771
772 m = state->m;
773 /*
774 * transport mode ipsec (before the 1st tunnel mode) is already
775 * processed by ipsec6_output_trans().
776 */
777 for (isr = sp->req; isr; isr = isr->next) {
778 if (isr->saidx.mode == IPSEC_MODE_TUNNEL)
779 break;
780 }
781
782 IPSECREQUEST_LOCK(isr); /* insure SA contents don't change */
783 isr = ipsec_nextisr(m, isr, AF_INET6, &saidx, &error);
784 if (isr == NULL) {
785 if (error != 0)
786 goto bad;
787 return EJUSTRETURN;
788 }
789
790 #ifdef DEV_ENC
791 encif->if_opackets++;
792 encif->if_obytes += m->m_pkthdr.len;
793
794 /* pass the mbuf to enc0 for bpf processing */
795 ipsec_bpf(m, isr->sav, AF_INET6, ENC_OUT|ENC_BEFORE);
796 /* pass the mbuf to enc0 for packet filtering */
797 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_BEFORE)) != 0)
798 goto bad;
799 #endif
800
801 /*
802 * There may be the case that SA status will be changed when
803 * we are refering to one. So calling splsoftnet().
804 */
805 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) {
806 /*
807 * build IPsec tunnel.
808 */
809 /* XXX should be processed with other familiy */
810 if (isr->sav->sah->saidx.src.sa.sa_family != AF_INET6) {
811 ipseclog((LOG_ERR, "%s: family mismatched between "
812 "inner and outer, spi=%u\n", __func__,
813 ntohl(isr->sav->spi)));
814 V_ipsec6stat.ips_out_inval++;
815 error = EAFNOSUPPORT;
816 goto bad;
817 }
818
819 m = ipsec6_splithdr(m);
820 if (!m) {
821 V_ipsec6stat.ips_out_nomem++;
822 error = ENOMEM;
823 goto bad;
824 }
825 error = ipsec6_encapsulate(m, isr->sav);
826 if (error) {
827 m = NULL;
828 goto bad;
829 }
830 ip6 = mtod(m, struct ip6_hdr *);
831
832 state->ro = &isr->sav->sah->sa_route;
833 state->dst = (struct sockaddr *)&state->ro->ro_dst;
834 dst6 = (struct sockaddr_in6 *)state->dst;
835 if (state->ro->ro_rt
836 && ((state->ro->ro_rt->rt_flags & RTF_UP) == 0
837 || !IN6_ARE_ADDR_EQUAL(&dst6->sin6_addr, &ip6->ip6_dst))) {
838 RTFREE(state->ro->ro_rt);
839 state->ro->ro_rt = NULL;
840 }
841 if (state->ro->ro_rt == NULL) {
842 bzero(dst6, sizeof(*dst6));
843 dst6->sin6_family = AF_INET6;
844 dst6->sin6_len = sizeof(*dst6);
845 dst6->sin6_addr = ip6->ip6_dst;
846 rtalloc(state->ro);
847 }
848 if (state->ro->ro_rt == NULL) {
849 V_ip6stat.ip6s_noroute++;
850 V_ipsec6stat.ips_out_noroute++;
851 error = EHOSTUNREACH;
852 goto bad;
853 }
854
855 /* adjust state->dst if tunnel endpoint is offlink */
856 if (state->ro->ro_rt->rt_flags & RTF_GATEWAY) {
857 state->dst = (struct sockaddr *)state->ro->ro_rt->rt_gateway;
858 dst6 = (struct sockaddr_in6 *)state->dst;
859 }
860 }
861
862 m = ipsec6_splithdr(m);
863 if (!m) {
864 V_ipsec6stat.ips_out_nomem++;
865 error = ENOMEM;
866 goto bad;
867 }
868 ip6 = mtod(m, struct ip6_hdr *);
869
870 #ifdef DEV_ENC
871 /* pass the mbuf to enc0 for bpf processing */
872 ipsec_bpf(m, isr->sav, AF_INET6, ENC_OUT|ENC_AFTER);
873 /* pass the mbuf to enc0 for packet filtering */
874 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_AFTER)) != 0)
875 goto bad;
876 #endif
877
878 error = (*isr->sav->tdb_xform->xf_output)(m, isr, NULL,
879 sizeof (struct ip6_hdr),
880 offsetof(struct ip6_hdr, ip6_nxt));
881 IPSECREQUEST_UNLOCK(isr);
882 return error;
883 bad:
884 if (isr)
885 IPSECREQUEST_UNLOCK(isr);
886 if (m)
887 m_freem(m);
888 state->m = NULL;
889 return error;
890 }
891 #endif /*INET6*/
Cache object: bed7546e225e6ef63dd0595d36ed4160
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