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/9.0/sys/netipsec/ipsec_output.c 223637 2011-06-28 11:57:25Z bz $
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 sav = isr->next->sav;
169 saidx = &sav->sah->saidx;
170 switch (saidx->dst.sa.sa_family) {
171 #ifdef INET
172 case AF_INET:
173 return ipsec4_process_packet(m, isr->next, 0, 0);
174 /* NOTREACHED */
175 #endif
176 #ifdef notyet
177 #ifdef INET6
178 case AF_INET6:
179 /* XXX */
180 ipsec6_output_trans()
181 ipsec6_output_tunnel()
182 /* NOTREACHED */
183 #endif /* INET6 */
184 #endif
185 default:
186 DPRINTF(("%s: unknown protocol family %u\n", __func__,
187 saidx->dst.sa.sa_family));
188 error = ENXIO;
189 goto bad;
190 }
191 }
192 key_sa_recordxfer(sav, m); /* record data transfer */
193
194 m_addr_changed(m);
195
196 /*
197 * We're done with IPsec processing, transmit the packet using the
198 * appropriate network protocol (IP or IPv6). SPD lookup will be
199 * performed again there.
200 */
201 switch (saidx->dst.sa.sa_family) {
202 #ifdef INET
203 struct ip *ip;
204 case AF_INET:
205 ip = mtod(m, struct ip *);
206 ip->ip_len = ntohs(ip->ip_len);
207 ip->ip_off = ntohs(ip->ip_off);
208
209 #ifdef IPSEC_NAT_T
210 /*
211 * If NAT-T is enabled, now that all IPsec processing is done
212 * insert UDP encapsulation header after IP header.
213 */
214 if (sav->natt_type) {
215 #ifdef _IP_VHL
216 const int hlen = IP_VHL_HL(ip->ip_vhl);
217 #else
218 const int hlen = (ip->ip_hl << 2);
219 #endif
220 int size, off;
221 struct mbuf *mi;
222 struct udphdr *udp;
223
224 size = sizeof(struct udphdr);
225 if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE) {
226 /*
227 * draft-ietf-ipsec-nat-t-ike-0[01].txt and
228 * draft-ietf-ipsec-udp-encaps-(00/)01.txt,
229 * ignoring possible AH mode
230 * non-IKE marker + non-ESP marker
231 * from draft-ietf-ipsec-udp-encaps-00.txt.
232 */
233 size += sizeof(u_int64_t);
234 }
235 mi = m_makespace(m, hlen, size, &off);
236 if (mi == NULL) {
237 DPRINTF(("%s: m_makespace for udphdr failed\n",
238 __func__));
239 error = ENOBUFS;
240 goto bad;
241 }
242
243 udp = (struct udphdr *)(mtod(mi, caddr_t) + off);
244 if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE)
245 udp->uh_sport = htons(UDP_ENCAP_ESPINUDP_PORT);
246 else
247 udp->uh_sport =
248 KEY_PORTFROMSADDR(&sav->sah->saidx.src);
249 udp->uh_dport = KEY_PORTFROMSADDR(&sav->sah->saidx.dst);
250 udp->uh_sum = 0;
251 udp->uh_ulen = htons(m->m_pkthdr.len - hlen);
252 ip->ip_len = m->m_pkthdr.len;
253 ip->ip_p = IPPROTO_UDP;
254
255 if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE)
256 *(u_int64_t *)(udp + 1) = 0;
257 }
258 #endif /* IPSEC_NAT_T */
259
260 return ip_output(m, NULL, NULL, IP_RAWOUTPUT, NULL, NULL);
261 #endif /* INET */
262 #ifdef INET6
263 case AF_INET6:
264 /*
265 * We don't need massage, IPv6 header fields are always in
266 * net endian.
267 */
268 return ip6_output(m, NULL, NULL, 0, NULL, NULL, NULL);
269 #endif /* INET6 */
270 }
271 panic("ipsec_process_done");
272 bad:
273 m_freem(m);
274 return (error);
275 }
276
277 static struct ipsecrequest *
278 ipsec_nextisr(
279 struct mbuf *m,
280 struct ipsecrequest *isr,
281 int af,
282 struct secasindex *saidx,
283 int *error
284 )
285 {
286 #define IPSEC_OSTAT(x,y,z) (isr->saidx.proto == IPPROTO_ESP ? (x)++ : \
287 isr->saidx.proto == IPPROTO_AH ? (y)++ : (z)++)
288 struct secasvar *sav;
289
290 IPSECREQUEST_LOCK_ASSERT(isr);
291
292 IPSEC_ASSERT(af == AF_INET || af == AF_INET6,
293 ("invalid address family %u", af));
294 again:
295 /*
296 * Craft SA index to search for proper SA. Note that
297 * we only fillin unspecified SA peers for transport
298 * mode; for tunnel mode they must already be filled in.
299 */
300 *saidx = isr->saidx;
301 if (isr->saidx.mode == IPSEC_MODE_TRANSPORT) {
302 /* Fillin unspecified SA peers only for transport mode */
303 if (af == AF_INET) {
304 struct sockaddr_in *sin;
305 struct ip *ip = mtod(m, struct ip *);
306
307 if (saidx->src.sa.sa_len == 0) {
308 sin = &saidx->src.sin;
309 sin->sin_len = sizeof(*sin);
310 sin->sin_family = AF_INET;
311 sin->sin_port = IPSEC_PORT_ANY;
312 sin->sin_addr = ip->ip_src;
313 }
314 if (saidx->dst.sa.sa_len == 0) {
315 sin = &saidx->dst.sin;
316 sin->sin_len = sizeof(*sin);
317 sin->sin_family = AF_INET;
318 sin->sin_port = IPSEC_PORT_ANY;
319 sin->sin_addr = ip->ip_dst;
320 }
321 } else {
322 struct sockaddr_in6 *sin6;
323 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
324
325 if (saidx->src.sin6.sin6_len == 0) {
326 sin6 = (struct sockaddr_in6 *)&saidx->src;
327 sin6->sin6_len = sizeof(*sin6);
328 sin6->sin6_family = AF_INET6;
329 sin6->sin6_port = IPSEC_PORT_ANY;
330 sin6->sin6_addr = ip6->ip6_src;
331 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) {
332 /* fix scope id for comparing SPD */
333 sin6->sin6_addr.s6_addr16[1] = 0;
334 sin6->sin6_scope_id =
335 ntohs(ip6->ip6_src.s6_addr16[1]);
336 }
337 }
338 if (saidx->dst.sin6.sin6_len == 0) {
339 sin6 = (struct sockaddr_in6 *)&saidx->dst;
340 sin6->sin6_len = sizeof(*sin6);
341 sin6->sin6_family = AF_INET6;
342 sin6->sin6_port = IPSEC_PORT_ANY;
343 sin6->sin6_addr = ip6->ip6_dst;
344 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) {
345 /* fix scope id for comparing SPD */
346 sin6->sin6_addr.s6_addr16[1] = 0;
347 sin6->sin6_scope_id =
348 ntohs(ip6->ip6_dst.s6_addr16[1]);
349 }
350 }
351 }
352 }
353
354 /*
355 * Lookup SA and validate it.
356 */
357 *error = key_checkrequest(isr, saidx);
358 if (*error != 0) {
359 /*
360 * IPsec processing is required, but no SA found.
361 * I assume that key_acquire() had been called
362 * to get/establish the SA. Here I discard
363 * this packet because it is responsibility for
364 * upper layer to retransmit the packet.
365 */
366 V_ipsec4stat.ips_out_nosa++;
367 goto bad;
368 }
369 sav = isr->sav;
370 if (sav == NULL) {
371 IPSEC_ASSERT(ipsec_get_reqlevel(isr) == IPSEC_LEVEL_USE,
372 ("no SA found, but required; level %u",
373 ipsec_get_reqlevel(isr)));
374 IPSECREQUEST_UNLOCK(isr);
375 isr = isr->next;
376 /*
377 * If isr is NULL, we found a 'use' policy w/o SA.
378 * Return w/o error and w/o isr so we can drop out
379 * and continue w/o IPsec processing.
380 */
381 if (isr == NULL)
382 return isr;
383 IPSECREQUEST_LOCK(isr);
384 goto again;
385 }
386
387 /*
388 * Check system global policy controls.
389 */
390 if ((isr->saidx.proto == IPPROTO_ESP && !V_esp_enable) ||
391 (isr->saidx.proto == IPPROTO_AH && !V_ah_enable) ||
392 (isr->saidx.proto == IPPROTO_IPCOMP && !V_ipcomp_enable)) {
393 DPRINTF(("%s: IPsec outbound packet dropped due"
394 " to policy (check your sysctls)\n", __func__));
395 IPSEC_OSTAT(V_espstat.esps_pdrops, V_ahstat.ahs_pdrops,
396 V_ipcompstat.ipcomps_pdrops);
397 *error = EHOSTUNREACH;
398 goto bad;
399 }
400
401 /*
402 * Sanity check the SA contents for the caller
403 * before they invoke the xform output method.
404 */
405 if (sav->tdb_xform == NULL) {
406 DPRINTF(("%s: no transform for SA\n", __func__));
407 IPSEC_OSTAT(V_espstat.esps_noxform, V_ahstat.ahs_noxform,
408 V_ipcompstat.ipcomps_noxform);
409 *error = EHOSTUNREACH;
410 goto bad;
411 }
412 return isr;
413 bad:
414 IPSEC_ASSERT(*error != 0, ("error return w/ no error code"));
415 IPSECREQUEST_UNLOCK(isr);
416 return NULL;
417 #undef IPSEC_OSTAT
418 }
419
420 #ifdef INET
421 /*
422 * IPsec output logic for IPv4.
423 */
424 int
425 ipsec4_process_packet(
426 struct mbuf *m,
427 struct ipsecrequest *isr,
428 int flags,
429 int tunalready)
430 {
431 struct secasindex saidx;
432 struct secasvar *sav;
433 struct ip *ip;
434 int error, i, off;
435
436 IPSEC_ASSERT(m != NULL, ("null mbuf"));
437 IPSEC_ASSERT(isr != NULL, ("null isr"));
438
439 IPSECREQUEST_LOCK(isr); /* insure SA contents don't change */
440
441 isr = ipsec_nextisr(m, isr, AF_INET, &saidx, &error);
442 if (isr == NULL) {
443 if (error != 0)
444 goto bad;
445 return EJUSTRETURN;
446 }
447
448 sav = isr->sav;
449
450 #ifdef DEV_ENC
451 encif->if_opackets++;
452 encif->if_obytes += m->m_pkthdr.len;
453
454 /* pass the mbuf to enc0 for bpf processing */
455 ipsec_bpf(m, sav, AF_INET, ENC_OUT|ENC_BEFORE);
456 /* pass the mbuf to enc0 for packet filtering */
457 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_BEFORE)) != 0)
458 goto bad;
459 #endif
460
461 if (!tunalready) {
462 union sockaddr_union *dst = &sav->sah->saidx.dst;
463 int setdf;
464
465 /*
466 * Collect IP_DF state from the outer header.
467 */
468 if (dst->sa.sa_family == AF_INET) {
469 if (m->m_len < sizeof (struct ip) &&
470 (m = m_pullup(m, sizeof (struct ip))) == NULL) {
471 error = ENOBUFS;
472 goto bad;
473 }
474 ip = mtod(m, struct ip *);
475 /* Honor system-wide control of how to handle IP_DF */
476 switch (V_ip4_ipsec_dfbit) {
477 case 0: /* clear in outer header */
478 case 1: /* set in outer header */
479 setdf = V_ip4_ipsec_dfbit;
480 break;
481 default: /* propagate to outer header */
482 setdf = ntohs(ip->ip_off & IP_DF);
483 break;
484 }
485 } else {
486 ip = NULL; /* keep compiler happy */
487 setdf = 0;
488 }
489 /* Do the appropriate encapsulation, if necessary */
490 if (isr->saidx.mode == IPSEC_MODE_TUNNEL || /* Tunnel requ'd */
491 dst->sa.sa_family != AF_INET || /* PF mismatch */
492 #if 0
493 (sav->flags & SADB_X_SAFLAGS_TUNNEL) || /* Tunnel requ'd */
494 sav->tdb_xform->xf_type == XF_IP4 || /* ditto */
495 #endif
496 (dst->sa.sa_family == AF_INET && /* Proxy */
497 dst->sin.sin_addr.s_addr != INADDR_ANY &&
498 dst->sin.sin_addr.s_addr != ip->ip_dst.s_addr)) {
499 struct mbuf *mp;
500
501 /* Fix IPv4 header checksum and length */
502 if (m->m_len < sizeof (struct ip) &&
503 (m = m_pullup(m, sizeof (struct ip))) == NULL) {
504 error = ENOBUFS;
505 goto bad;
506 }
507 ip = mtod(m, struct ip *);
508 ip->ip_len = htons(m->m_pkthdr.len);
509 ip->ip_sum = 0;
510 #ifdef _IP_VHL
511 if (ip->ip_vhl == IP_VHL_BORING)
512 ip->ip_sum = in_cksum_hdr(ip);
513 else
514 ip->ip_sum = in_cksum(m,
515 _IP_VHL_HL(ip->ip_vhl) << 2);
516 #else
517 ip->ip_sum = in_cksum(m, ip->ip_hl << 2);
518 #endif
519
520 /* Encapsulate the packet */
521 error = ipip_output(m, isr, &mp, 0, 0);
522 if (mp == NULL && !error) {
523 /* Should never happen. */
524 DPRINTF(("%s: ipip_output returns no mbuf and "
525 "no error!", __func__));
526 error = EFAULT;
527 }
528 if (error) {
529 if (mp) {
530 /* XXX: Should never happen! */
531 m_freem(mp);
532 }
533 m = NULL; /* ipip_output() already freed it */
534 goto bad;
535 }
536 m = mp, mp = NULL;
537 /*
538 * ipip_output clears IP_DF in the new header. If
539 * we need to propagate IP_DF from the outer header,
540 * then we have to do it here.
541 *
542 * XXX shouldn't assume what ipip_output does.
543 */
544 if (dst->sa.sa_family == AF_INET && setdf) {
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_off = ntohs(ip->ip_off);
552 ip->ip_off |= IP_DF;
553 ip->ip_off = htons(ip->ip_off);
554 }
555 }
556 }
557
558 #ifdef DEV_ENC
559 /* pass the mbuf to enc0 for bpf processing */
560 ipsec_bpf(m, sav, AF_INET, ENC_OUT|ENC_AFTER);
561 /* pass the mbuf to enc0 for packet filtering */
562 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_AFTER)) != 0)
563 goto bad;
564 #endif
565
566 /*
567 * Dispatch to the appropriate IPsec transform logic. The
568 * packet will be returned for transmission after crypto
569 * processing, etc. are completed. For encapsulation we
570 * bypass this call because of the explicit call done above
571 * (necessary to deal with IP_DF handling for IPv4).
572 *
573 * NB: m & sav are ``passed to caller'' who's reponsible for
574 * for reclaiming their resources.
575 */
576 if (sav->tdb_xform->xf_type != XF_IP4) {
577 ip = mtod(m, struct ip *);
578 i = ip->ip_hl << 2;
579 off = offsetof(struct ip, ip_p);
580 error = (*sav->tdb_xform->xf_output)(m, isr, NULL, i, off);
581 } else {
582 error = ipsec_process_done(m, isr);
583 }
584 IPSECREQUEST_UNLOCK(isr);
585 return error;
586 bad:
587 if (isr)
588 IPSECREQUEST_UNLOCK(isr);
589 if (m)
590 m_freem(m);
591 return error;
592 }
593 #endif
594
595 #ifdef INET6
596 /*
597 * Chop IP6 header from the payload.
598 */
599 static struct mbuf *
600 ipsec6_splithdr(struct mbuf *m)
601 {
602 struct mbuf *mh;
603 struct ip6_hdr *ip6;
604 int hlen;
605
606 IPSEC_ASSERT(m->m_len >= sizeof (struct ip6_hdr),
607 ("first mbuf too short, len %u", m->m_len));
608 ip6 = mtod(m, struct ip6_hdr *);
609 hlen = sizeof(struct ip6_hdr);
610 if (m->m_len > hlen) {
611 MGETHDR(mh, M_DONTWAIT, MT_DATA);
612 if (!mh) {
613 m_freem(m);
614 return NULL;
615 }
616 M_MOVE_PKTHDR(mh, m);
617 MH_ALIGN(mh, hlen);
618 m->m_len -= hlen;
619 m->m_data += hlen;
620 mh->m_next = m;
621 m = mh;
622 m->m_len = hlen;
623 bcopy((caddr_t)ip6, mtod(m, caddr_t), hlen);
624 } else if (m->m_len < hlen) {
625 m = m_pullup(m, hlen);
626 if (!m)
627 return NULL;
628 }
629 return m;
630 }
631
632 /*
633 * IPsec output logic for IPv6, transport mode.
634 */
635 int
636 ipsec6_output_trans(
637 struct ipsec_output_state *state,
638 u_char *nexthdrp,
639 struct mbuf *mprev,
640 struct secpolicy *sp,
641 int flags,
642 int *tun)
643 {
644 struct ipsecrequest *isr;
645 struct secasindex saidx;
646 int error = 0;
647 struct mbuf *m;
648
649 IPSEC_ASSERT(state != NULL, ("null state"));
650 IPSEC_ASSERT(state->m != NULL, ("null m"));
651 IPSEC_ASSERT(nexthdrp != NULL, ("null nexthdrp"));
652 IPSEC_ASSERT(mprev != NULL, ("null mprev"));
653 IPSEC_ASSERT(sp != NULL, ("null sp"));
654 IPSEC_ASSERT(tun != NULL, ("null tun"));
655
656 KEYDEBUG(KEYDEBUG_IPSEC_DATA,
657 printf("%s: applied SP\n", __func__);
658 kdebug_secpolicy(sp));
659
660 isr = sp->req;
661 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) {
662 /* the rest will be handled by ipsec6_output_tunnel() */
663 *tun = 1; /* need tunnel-mode processing */
664 return 0;
665 }
666
667 *tun = 0;
668 m = state->m;
669
670 IPSECREQUEST_LOCK(isr); /* insure SA contents don't change */
671 isr = ipsec_nextisr(m, isr, AF_INET6, &saidx, &error);
672 if (isr == NULL) {
673 if (error != 0) {
674 #ifdef notdef
675 /* XXX should notification be done for all errors ? */
676 /*
677 * Notify the fact that the packet is discarded
678 * to ourselves. I believe this is better than
679 * just silently discarding. (jinmei@kame.net)
680 * XXX: should we restrict the error to TCP packets?
681 * XXX: should we directly notify sockets via
682 * pfctlinputs?
683 */
684 icmp6_error(m, ICMP6_DST_UNREACH,
685 ICMP6_DST_UNREACH_ADMIN, 0);
686 m = NULL; /* NB: icmp6_error frees mbuf */
687 #endif
688 goto bad;
689 }
690 return EJUSTRETURN;
691 }
692
693 error = (*isr->sav->tdb_xform->xf_output)(m, isr, NULL,
694 sizeof (struct ip6_hdr),
695 offsetof(struct ip6_hdr,
696 ip6_nxt));
697 IPSECREQUEST_UNLOCK(isr);
698 return error;
699 bad:
700 if (isr)
701 IPSECREQUEST_UNLOCK(isr);
702 if (m)
703 m_freem(m);
704 state->m = NULL;
705 return error;
706 }
707
708 static int
709 ipsec6_encapsulate(struct mbuf *m, struct secasvar *sav)
710 {
711 struct ip6_hdr *oip6;
712 struct ip6_hdr *ip6;
713 size_t plen;
714
715 /* can't tunnel between different AFs */
716 if (sav->sah->saidx.src.sa.sa_family != AF_INET6 ||
717 sav->sah->saidx.dst.sa.sa_family != AF_INET6) {
718 m_freem(m);
719 return EINVAL;
720 }
721 IPSEC_ASSERT(m->m_len == sizeof (struct ip6_hdr),
722 ("mbuf wrong size; len %u", m->m_len));
723
724
725 /*
726 * grow the mbuf to accomodate the new IPv6 header.
727 */
728 plen = m->m_pkthdr.len;
729 if (M_LEADINGSPACE(m->m_next) < sizeof(struct ip6_hdr)) {
730 struct mbuf *n;
731 MGET(n, M_DONTWAIT, MT_DATA);
732 if (!n) {
733 m_freem(m);
734 return ENOBUFS;
735 }
736 n->m_len = sizeof(struct ip6_hdr);
737 n->m_next = m->m_next;
738 m->m_next = n;
739 m->m_pkthdr.len += sizeof(struct ip6_hdr);
740 oip6 = mtod(n, struct ip6_hdr *);
741 } else {
742 m->m_next->m_len += sizeof(struct ip6_hdr);
743 m->m_next->m_data -= sizeof(struct ip6_hdr);
744 m->m_pkthdr.len += sizeof(struct ip6_hdr);
745 oip6 = mtod(m->m_next, struct ip6_hdr *);
746 }
747 ip6 = mtod(m, struct ip6_hdr *);
748 bcopy((caddr_t)ip6, (caddr_t)oip6, sizeof(struct ip6_hdr));
749
750 /* Fake link-local scope-class addresses */
751 if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_src))
752 oip6->ip6_src.s6_addr16[1] = 0;
753 if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_dst))
754 oip6->ip6_dst.s6_addr16[1] = 0;
755
756 /* construct new IPv6 header. see RFC 2401 5.1.2.2 */
757 /* ECN consideration. */
758 ip6_ecn_ingress(V_ip6_ipsec_ecn, &ip6->ip6_flow, &oip6->ip6_flow);
759 if (plen < IPV6_MAXPACKET - sizeof(struct ip6_hdr))
760 ip6->ip6_plen = htons(plen);
761 else {
762 /* ip6->ip6_plen will be updated in ip6_output() */
763 }
764 ip6->ip6_nxt = IPPROTO_IPV6;
765 ip6->ip6_src = sav->sah->saidx.src.sin6.sin6_addr;
766 ip6->ip6_dst = sav->sah->saidx.dst.sin6.sin6_addr;
767 ip6->ip6_hlim = IPV6_DEFHLIM;
768
769 /* XXX Should ip6_src be updated later ? */
770
771 return 0;
772 }
773
774 /*
775 * IPsec output logic for IPv6, tunnel mode.
776 */
777 int
778 ipsec6_output_tunnel(struct ipsec_output_state *state, struct secpolicy *sp, int flags)
779 {
780 struct ip6_hdr *ip6;
781 struct ipsecrequest *isr;
782 struct secasindex saidx;
783 int error;
784 struct sockaddr_in6 *dst6;
785 struct mbuf *m;
786
787 IPSEC_ASSERT(state != NULL, ("null state"));
788 IPSEC_ASSERT(state->m != NULL, ("null m"));
789 IPSEC_ASSERT(sp != NULL, ("null sp"));
790
791 KEYDEBUG(KEYDEBUG_IPSEC_DATA,
792 printf("%s: applied SP\n", __func__);
793 kdebug_secpolicy(sp));
794
795 m = state->m;
796 /*
797 * transport mode ipsec (before the 1st tunnel mode) is already
798 * processed by ipsec6_output_trans().
799 */
800 for (isr = sp->req; isr; isr = isr->next) {
801 if (isr->saidx.mode == IPSEC_MODE_TUNNEL)
802 break;
803 }
804
805 IPSECREQUEST_LOCK(isr); /* insure SA contents don't change */
806 isr = ipsec_nextisr(m, isr, AF_INET6, &saidx, &error);
807 if (isr == NULL) {
808 if (error != 0)
809 goto bad;
810 return EJUSTRETURN;
811 }
812
813 #ifdef DEV_ENC
814 encif->if_opackets++;
815 encif->if_obytes += m->m_pkthdr.len;
816
817 /* pass the mbuf to enc0 for bpf processing */
818 ipsec_bpf(m, isr->sav, AF_INET6, ENC_OUT|ENC_BEFORE);
819 /* pass the mbuf to enc0 for packet filtering */
820 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_BEFORE)) != 0)
821 goto bad;
822 #endif
823
824 /*
825 * There may be the case that SA status will be changed when
826 * we are refering to one. So calling splsoftnet().
827 */
828 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) {
829 /*
830 * build IPsec tunnel.
831 */
832 /* XXX should be processed with other familiy */
833 if (isr->sav->sah->saidx.src.sa.sa_family != AF_INET6) {
834 ipseclog((LOG_ERR, "%s: family mismatched between "
835 "inner and outer, spi=%u\n", __func__,
836 ntohl(isr->sav->spi)));
837 V_ipsec6stat.ips_out_inval++;
838 error = EAFNOSUPPORT;
839 goto bad;
840 }
841
842 m = ipsec6_splithdr(m);
843 if (!m) {
844 V_ipsec6stat.ips_out_nomem++;
845 error = ENOMEM;
846 goto bad;
847 }
848 error = ipsec6_encapsulate(m, isr->sav);
849 if (error) {
850 m = NULL;
851 goto bad;
852 }
853 ip6 = mtod(m, struct ip6_hdr *);
854
855 state->ro =
856 (struct route *)&isr->sav->sah->route_cache.sin6_route;
857 state->dst = (struct sockaddr *)&state->ro->ro_dst;
858 dst6 = (struct sockaddr_in6 *)state->dst;
859 if (state->ro->ro_rt
860 && ((state->ro->ro_rt->rt_flags & RTF_UP) == 0
861 || !IN6_ARE_ADDR_EQUAL(&dst6->sin6_addr, &ip6->ip6_dst))) {
862 RTFREE(state->ro->ro_rt);
863 state->ro->ro_rt = NULL;
864 }
865 if (state->ro->ro_rt == NULL) {
866 bzero(dst6, sizeof(*dst6));
867 dst6->sin6_family = AF_INET6;
868 dst6->sin6_len = sizeof(*dst6);
869 dst6->sin6_addr = ip6->ip6_dst;
870 rtalloc(state->ro);
871 }
872 if (state->ro->ro_rt == NULL) {
873 V_ip6stat.ip6s_noroute++;
874 V_ipsec6stat.ips_out_noroute++;
875 error = EHOSTUNREACH;
876 goto bad;
877 }
878
879 /* adjust state->dst if tunnel endpoint is offlink */
880 if (state->ro->ro_rt->rt_flags & RTF_GATEWAY)
881 state->dst = (struct sockaddr *)state->ro->ro_rt->rt_gateway;
882 }
883
884 m = ipsec6_splithdr(m);
885 if (!m) {
886 V_ipsec6stat.ips_out_nomem++;
887 error = ENOMEM;
888 goto bad;
889 }
890 ip6 = mtod(m, struct ip6_hdr *);
891
892 #ifdef DEV_ENC
893 /* pass the mbuf to enc0 for bpf processing */
894 ipsec_bpf(m, isr->sav, AF_INET6, ENC_OUT|ENC_AFTER);
895 /* pass the mbuf to enc0 for packet filtering */
896 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_AFTER)) != 0)
897 goto bad;
898 #endif
899
900 error = (*isr->sav->tdb_xform->xf_output)(m, isr, NULL,
901 sizeof (struct ip6_hdr),
902 offsetof(struct ip6_hdr, ip6_nxt));
903 IPSECREQUEST_UNLOCK(isr);
904 return error;
905 bad:
906 if (isr)
907 IPSECREQUEST_UNLOCK(isr);
908 if (m)
909 m_freem(m);
910 state->m = NULL;
911 return error;
912 }
913 #endif /*INET6*/
Cache object: 83e10a46b1edba5102ff08f95934bd34
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