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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  * $FreeBSD$
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/if_var.h>
48 #include <net/pfil.h>
49 #include <net/route.h>
50 #include <net/vnet.h>
51
52 #include <netinet/in.h>
53 #include <netinet/in_systm.h>
54 #include <netinet/ip.h>
55 #include <netinet/ip_var.h>
56 #include <netinet/in_var.h>
57 #include <netinet/ip_ecn.h>
58 #ifdef INET6
59 #include <netinet6/ip6_ecn.h>
60 #endif
61
62 #include <netinet/ip6.h>
63 #ifdef INET6
64 #include <netinet6/ip6_var.h>
65 #endif
66 #include <netinet/in_pcb.h>
67 #ifdef INET6
68 #include <netinet/icmp6.h>
69 #endif
70
71 #include <netipsec/ipsec.h>
72 #ifdef INET6
73 #include <netipsec/ipsec6.h>
74 #endif
75 #include <netipsec/ah_var.h>
76 #include <netipsec/esp_var.h>
77 #include <netipsec/ipcomp_var.h>
78
79 #include <netipsec/xform.h>
80
81 #include <netipsec/key.h>
82 #include <netipsec/keydb.h>
83 #include <netipsec/key_debug.h>
84
85 #include <machine/in_cksum.h>
86
87 #ifdef IPSEC_NAT_T
88 #include <netinet/udp.h>
89 #endif
90
91 #ifdef DEV_ENC
92 #include <net/if_enc.h>
93 #endif
94
95
96 int
97 ipsec_process_done(struct mbuf *m, struct ipsecrequest *isr)
98 {
99         struct tdb_ident *tdbi;
100         struct m_tag *mtag;
101         struct secasvar *sav;
102         struct secasindex *saidx;
103         int error;
104
105         IPSEC_ASSERT(m != NULL, ("null mbuf"));
106         IPSEC_ASSERT(isr != NULL, ("null ISR"));
107         sav = isr->sav;
108         IPSEC_ASSERT(sav != NULL, ("null SA"));
109         IPSEC_ASSERT(sav->sah != NULL, ("null SAH"));
110
111         saidx = &sav->sah->saidx;
112         switch (saidx->dst.sa.sa_family) {
113 #ifdef INET
114         case AF_INET:
115                 /* Fix the header length, for AH processing. */
116                 mtod(m, struct ip *)->ip_len = htons(m->m_pkthdr.len);
117                 break;
118 #endif /* INET */
119 #ifdef INET6
120         case AF_INET6:
121                 /* Fix the header length, for AH processing. */
122                 if (m->m_pkthdr.len < sizeof (struct ip6_hdr)) {
123                         error = ENXIO;
124                         goto bad;
125                 }
126                 if (m->m_pkthdr.len - sizeof (struct ip6_hdr) > IPV6_MAXPACKET) {
127                         /* No jumbogram support. */
128                         error = ENXIO;  /*?*/
129                         goto bad;
130                 }
131                 mtod(m, struct ip6_hdr *)->ip6_plen =
132                         htons(m->m_pkthdr.len - sizeof(struct ip6_hdr));
133                 break;
134 #endif /* INET6 */
135         default:
136                 DPRINTF(("%s: unknown protocol family %u\n", __func__,
137                     saidx->dst.sa.sa_family));
138                 error = ENXIO;
139                 goto bad;
140         }
141
142         /*
143          * Add a record of what we've done or what needs to be done to the
144          * packet.
145          */
146         mtag = m_tag_get(PACKET_TAG_IPSEC_OUT_DONE,
147                         sizeof(struct tdb_ident), M_NOWAIT);
148         if (mtag == NULL) {
149                 DPRINTF(("%s: could not get packet tag\n", __func__));
150                 error = ENOMEM;
151                 goto bad;
152         }
153
154         tdbi = (struct tdb_ident *)(mtag + 1);
155         tdbi->dst = saidx->dst;
156         tdbi->proto = saidx->proto;
157         tdbi->spi = sav->spi;
158         m_tag_prepend(m, mtag);
159
160         /*
161          * If there's another (bundled) SA to apply, do so.
162          * Note that this puts a burden on the kernel stack size.
163          * If this is a problem we'll need to introduce a queue
164          * to set the packet on so we can unwind the stack before
165          * doing further processing.
166          */
167         if (isr->next) {
168                 IPSECSTAT_INC(ips_out_bundlesa);
169                 /* XXX-BZ currently only support same AF bundles. */
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                         return ipsec6_process_packet(m, isr->next);
181                         /* NOTREACHED */
182 #endif /* INET6 */
183 #endif
184                 default:
185                         DPRINTF(("%s: unknown protocol family %u\n", __func__,
186                             saidx->dst.sa.sa_family));
187                         error = ENXIO;
188                         goto bad;
189                 }
190         }
191         key_sa_recordxfer(sav, m);              /* record data transfer */
192
193         /*
194          * We're done with IPsec processing, transmit the packet using the
195          * appropriate network protocol (IP or IPv6). SPD lookup will be
196          * performed again there.
197          */
198         switch (saidx->dst.sa.sa_family) {
199 #ifdef INET
200         case AF_INET:
201 #ifdef IPSEC_NAT_T
202                 /*
203                  * If NAT-T is enabled, now that all IPsec processing is done
204                  * insert UDP encapsulation header after IP header.
205                  */
206                 if (sav->natt_type) {
207                         struct ip *ip = mtod(m, struct ip *);
208                         const int hlen = (ip->ip_hl << 2);
209                         int size, off;
210                         struct mbuf *mi;
211                         struct udphdr *udp;
212
213                         size = sizeof(struct udphdr);
214                         if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE) {
215                                 /*
216                                  * draft-ietf-ipsec-nat-t-ike-0[01].txt and
217                                  * draft-ietf-ipsec-udp-encaps-(00/)01.txt,
218                                  * ignoring possible AH mode
219                                  * non-IKE marker + non-ESP marker
220                                  * from draft-ietf-ipsec-udp-encaps-00.txt.
221                                  */
222                                 size += sizeof(u_int64_t);
223                         }
224                         mi = m_makespace(m, hlen, size, &off);
225                         if (mi == NULL) {
226                                 DPRINTF(("%s: m_makespace for udphdr failed\n",
227                                     __func__));
228                                 error = ENOBUFS;
229                                 goto bad;
230                         }
231
232                         udp = (struct udphdr *)(mtod(mi, caddr_t) + off);
233                         if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE)
234                                 udp->uh_sport = htons(UDP_ENCAP_ESPINUDP_PORT);
235                         else
236                                 udp->uh_sport =
237                                         KEY_PORTFROMSADDR(&sav->sah->saidx.src);
238                         udp->uh_dport = KEY_PORTFROMSADDR(&sav->sah->saidx.dst);
239                         udp->uh_sum = 0;
240                         udp->uh_ulen = htons(m->m_pkthdr.len - hlen);
241                         ip->ip_len = htons(m->m_pkthdr.len);
242                         ip->ip_p = IPPROTO_UDP;
243
244                         if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE)
245                                 *(u_int64_t *)(udp + 1) = 0;
246                 }
247 #endif /* IPSEC_NAT_T */
248
249                 return ip_output(m, NULL, NULL, IP_RAWOUTPUT, NULL, NULL);
250 #endif /* INET */
251 #ifdef INET6
252         case AF_INET6:
253                 /*
254                  * We don't need massage, IPv6 header fields are always in
255                  * net endian.
256                  */
257                 return ip6_output(m, NULL, NULL, 0, NULL, NULL, NULL);
258 #endif /* INET6 */
259         }
260         panic("ipsec_process_done");
261 bad:
262         m_freem(m);
263         return (error);
264 }
265
266 static struct ipsecrequest *
267 ipsec_nextisr(
268         struct mbuf *m,
269         struct ipsecrequest *isr,
270         int af,
271         struct secasindex *saidx,
272         int *error
273 )
274 {
275 #define IPSEC_OSTAT(name)       do {            \
276         if (isr->saidx.proto == IPPROTO_ESP)    \
277                 ESPSTAT_INC(esps_##name);       \
278         else if (isr->saidx.proto == IPPROTO_AH)\
279                 AHSTAT_INC(ahs_##name);         \
280         else                                    \
281                 IPCOMPSTAT_INC(ipcomps_##name); \
282 } while (0)
283         struct secasvar *sav;
284
285         IPSECREQUEST_LOCK_ASSERT(isr);
286
287         IPSEC_ASSERT(af == AF_INET || af == AF_INET6,
288                 ("invalid address family %u", af));
289 again:
290         /*
291          * Craft SA index to search for proper SA.  Note that
292          * we only fillin unspecified SA peers for transport
293          * mode; for tunnel mode they must already be filled in.
294          */
295         *saidx = isr->saidx;
296         if (isr->saidx.mode == IPSEC_MODE_TRANSPORT) {
297                 /* Fillin unspecified SA peers only for transport mode */
298                 if (af == AF_INET) {
299                         struct sockaddr_in *sin;
300                         struct ip *ip = mtod(m, struct ip *);
301
302                         if (saidx->src.sa.sa_len == 0) {
303                                 sin = &saidx->src.sin;
304                                 sin->sin_len = sizeof(*sin);
305                                 sin->sin_family = AF_INET;
306                                 sin->sin_port = IPSEC_PORT_ANY;
307                                 sin->sin_addr = ip->ip_src;
308                         }
309                         if (saidx->dst.sa.sa_len == 0) {
310                                 sin = &saidx->dst.sin;
311                                 sin->sin_len = sizeof(*sin);
312                                 sin->sin_family = AF_INET;
313                                 sin->sin_port = IPSEC_PORT_ANY;
314                                 sin->sin_addr = ip->ip_dst;
315                         }
316                 } else {
317                         struct sockaddr_in6 *sin6;
318                         struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
319
320                         if (saidx->src.sin6.sin6_len == 0) {
321                                 sin6 = (struct sockaddr_in6 *)&saidx->src;
322                                 sin6->sin6_len = sizeof(*sin6);
323                                 sin6->sin6_family = AF_INET6;
324                                 sin6->sin6_port = IPSEC_PORT_ANY;
325                                 sin6->sin6_addr = ip6->ip6_src;
326                                 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) {
327                                         /* fix scope id for comparing SPD */
328                                         sin6->sin6_addr.s6_addr16[1] = 0;
329                                         sin6->sin6_scope_id =
330                                             ntohs(ip6->ip6_src.s6_addr16[1]);
331                                 }
332                         }
333                         if (saidx->dst.sin6.sin6_len == 0) {
334                                 sin6 = (struct sockaddr_in6 *)&saidx->dst;
335                                 sin6->sin6_len = sizeof(*sin6);
336                                 sin6->sin6_family = AF_INET6;
337                                 sin6->sin6_port = IPSEC_PORT_ANY;
338                                 sin6->sin6_addr = ip6->ip6_dst;
339                                 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) {
340                                         /* fix scope id for comparing SPD */
341                                         sin6->sin6_addr.s6_addr16[1] = 0;
342                                         sin6->sin6_scope_id =
343                                             ntohs(ip6->ip6_dst.s6_addr16[1]);
344                                 }
345                         }
346                 }
347         }
348
349         /*
350          * Lookup SA and validate it.
351          */
352         *error = key_checkrequest(isr, saidx);
353         if (*error != 0) {
354                 /*
355                  * IPsec processing is required, but no SA found.
356                  * I assume that key_acquire() had been called
357                  * to get/establish the SA. Here I discard
358                  * this packet because it is responsibility for
359                  * upper layer to retransmit the packet.
360                  */
361                 IPSECSTAT_INC(ips_out_nosa);
362                 goto bad;
363         }
364         sav = isr->sav;
365         if (sav == NULL) {
366                 IPSEC_ASSERT(ipsec_get_reqlevel(isr) == IPSEC_LEVEL_USE,
367                         ("no SA found, but required; level %u",
368                         ipsec_get_reqlevel(isr)));
369                 IPSECREQUEST_UNLOCK(isr);
370                 isr = isr->next;
371                 /*
372                  * If isr is NULL, we found a 'use' policy w/o SA.
373                  * Return w/o error and w/o isr so we can drop out
374                  * and continue w/o IPsec processing.
375                  */
376                 if (isr == NULL)
377                         return isr;
378                 IPSECREQUEST_LOCK(isr);
379                 goto again;
380         }
381
382         /*
383          * Check system global policy controls.
384          */
385         if ((isr->saidx.proto == IPPROTO_ESP && !V_esp_enable) ||
386             (isr->saidx.proto == IPPROTO_AH && !V_ah_enable) ||
387             (isr->saidx.proto == IPPROTO_IPCOMP && !V_ipcomp_enable)) {
388                 DPRINTF(("%s: IPsec outbound packet dropped due"
389                         " to policy (check your sysctls)\n", __func__));
390                 IPSEC_OSTAT(pdrops);
391                 *error = EHOSTUNREACH;
392                 goto bad;
393         }
394
395         /*
396          * Sanity check the SA contents for the caller
397          * before they invoke the xform output method.
398          */
399         if (sav->tdb_xform == NULL) {
400                 DPRINTF(("%s: no transform for SA\n", __func__));
401                 IPSEC_OSTAT(noxform);
402                 *error = EHOSTUNREACH;
403                 goto bad;
404         }
405         return isr;
406 bad:
407         IPSEC_ASSERT(*error != 0, ("error return w/ no error code"));
408         IPSECREQUEST_UNLOCK(isr);
409         return NULL;
410 #undef IPSEC_OSTAT
411 }
412
413 #ifdef INET
414 /*
415  * IPsec output logic for IPv4.
416  */
417 int
418 ipsec4_process_packet(
419         struct mbuf *m,
420         struct ipsecrequest *isr,
421         int flags,
422         int tunalready)
423 {
424         struct secasindex saidx;
425         struct secasvar *sav;
426         struct ip *ip;
427         int error, i, off;
428
429         IPSEC_ASSERT(m != NULL, ("null mbuf"));
430         IPSEC_ASSERT(isr != NULL, ("null isr"));
431
432         IPSECREQUEST_LOCK(isr);         /* insure SA contents don't change */
433
434         isr = ipsec_nextisr(m, isr, AF_INET, &saidx, &error);
435         if (isr == NULL) {
436                 if (error != 0)
437                         goto bad;
438                 return EJUSTRETURN;
439         }
440
441         sav = isr->sav;
442
443 #ifdef DEV_ENC
444         encif->if_opackets++;
445         encif->if_obytes += m->m_pkthdr.len;
446
447         /* pass the mbuf to enc0 for bpf processing */
448         ipsec_bpf(m, sav, AF_INET, ENC_OUT|ENC_BEFORE);
449         /* pass the mbuf to enc0 for packet filtering */
450         if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_BEFORE)) != 0)
451                 goto bad;
452 #endif
453
454         if (!tunalready) {
455                 union sockaddr_union *dst = &sav->sah->saidx.dst;
456                 int setdf;
457
458                 /*
459                  * Collect IP_DF state from the outer header.
460                  */
461                 if (dst->sa.sa_family == AF_INET) {
462                         if (m->m_len < sizeof (struct ip) &&
463                             (m = m_pullup(m, sizeof (struct ip))) == NULL) {
464                                 error = ENOBUFS;
465                                 goto bad;
466                         }
467                         ip = mtod(m, struct ip *);
468                         /* Honor system-wide control of how to handle IP_DF */
469                         switch (V_ip4_ipsec_dfbit) {
470                         case 0:                 /* clear in outer header */
471                         case 1:                 /* set in outer header */
472                                 setdf = V_ip4_ipsec_dfbit;
473                                 break;
474                         default:                /* propagate to outer header */
475                                 setdf = ntohs(ip->ip_off & IP_DF);
476                                 break;
477                         }
478                 } else {
479                         ip = NULL;              /* keep compiler happy */
480                         setdf = 0;
481                 }
482                 /* Do the appropriate encapsulation, if necessary */
483                 if (isr->saidx.mode == IPSEC_MODE_TUNNEL || /* Tunnel requ'd */
484                     dst->sa.sa_family != AF_INET ||         /* PF mismatch */
485 #if 0
486                     (sav->flags & SADB_X_SAFLAGS_TUNNEL) || /* Tunnel requ'd */
487                     sav->tdb_xform->xf_type == XF_IP4 ||    /* ditto */
488 #endif
489                     (dst->sa.sa_family == AF_INET &&        /* Proxy */
490                      dst->sin.sin_addr.s_addr != INADDR_ANY &&
491                      dst->sin.sin_addr.s_addr != ip->ip_dst.s_addr)) {
492                         struct mbuf *mp;
493
494                         /* Fix IPv4 header checksum and length */
495                         if (m->m_len < sizeof (struct ip) &&
496                             (m = m_pullup(m, sizeof (struct ip))) == NULL) {
497                                 error = ENOBUFS;
498                                 goto bad;
499                         }
500                         ip = mtod(m, struct ip *);
501                         ip->ip_len = htons(m->m_pkthdr.len);
502                         ip->ip_sum = 0;
503                         ip->ip_sum = in_cksum(m, ip->ip_hl << 2);
504
505                         /* Encapsulate the packet */
506                         error = ipip_output(m, isr, &mp, 0, 0);
507                         if (mp == NULL && !error) {
508                                 /* Should never happen. */
509                                 DPRINTF(("%s: ipip_output returns no mbuf and "
510                                         "no error!", __func__));
511                                 error = EFAULT;
512                         }
513                         if (error) {
514                                 if (mp) {
515                                         /* XXX: Should never happen! */
516                                         m_freem(mp);
517                                 }
518                                 m = NULL; /* ipip_output() already freed it */
519                                 goto bad;
520                         }
521                         m = mp, mp = NULL;
522                         /*
523                          * ipip_output clears IP_DF in the new header.  If
524                          * we need to propagate IP_DF from the outer header,
525                          * then we have to do it here.
526                          *
527                          * XXX shouldn't assume what ipip_output does.
528                          */
529                         if (dst->sa.sa_family == AF_INET && setdf) {
530                                 if (m->m_len < sizeof (struct ip) &&
531                                     (m = m_pullup(m, sizeof (struct ip))) == NULL) {
532                                         error = ENOBUFS;
533                                         goto bad;
534                                 }
535                                 ip = mtod(m, struct ip *);
536                                 ip->ip_off = ntohs(ip->ip_off);
537                                 ip->ip_off |= IP_DF;
538                                 ip->ip_off = htons(ip->ip_off);
539                         }
540                 }
541         }
542
543 #ifdef DEV_ENC
544         /* pass the mbuf to enc0 for bpf processing */
545         ipsec_bpf(m, sav, sav->sah->saidx.dst.sa.sa_family, ENC_OUT|ENC_AFTER);
546         /* pass the mbuf to enc0 for packet filtering */
547         if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_AFTER)) != 0)
548                 goto bad;
549 #endif
550
551         /*
552          * Dispatch to the appropriate IPsec transform logic.  The
553          * packet will be returned for transmission after crypto
554          * processing, etc. are completed.  For encapsulation we
555          * bypass this call because of the explicit call done above
556          * (necessary to deal with IP_DF handling for IPv4).
557          *
558          * NB: m & sav are ``passed to caller'' who's reponsible for
559          *     for reclaiming their resources.
560          */
561         if (sav->tdb_xform->xf_type != XF_IP4) {
562                 union sockaddr_union *dst = &sav->sah->saidx.dst;
563                 switch(dst->sa.sa_family) {
564                 case AF_INET:
565                         ip = mtod(m, struct ip *);
566                         i = ip->ip_hl << 2;
567                         off = offsetof(struct ip, ip_p);
568                         break;
569 #ifdef INET6
570                 case AF_INET6:
571                         i = sizeof(struct ip6_hdr);
572                         off = offsetof(struct ip6_hdr, ip6_nxt);
573                         break;
574 #endif /* INET6 */
575                 default:
576                 DPRINTF(("%s: unsupported protocol family %u\n",
577                                  __func__, dst->sa.sa_family));
578                         error = EPFNOSUPPORT;
579                         IPSECSTAT_INC(ips_out_inval);
580                         goto bad;
581                 }
582                 error = (*sav->tdb_xform->xf_output)(m, isr, NULL, i, off);
583         } else {
584                 error = ipsec_process_done(m, isr);
585         }
586         IPSECREQUEST_UNLOCK(isr);
587         return error;
588 bad:
589         if (isr)
590                 IPSECREQUEST_UNLOCK(isr);
591         if (m)
592                 m_freem(m);
593         return error;
594 }
595 #endif
596
597
598 #ifdef INET6
599 static int
600 in6_sa_equal_addrwithscope(const struct sockaddr_in6 *sa, const struct in6_addr *ia)
601 {
602         struct in6_addr ia2;
603
604         memcpy(&ia2, &sa->sin6_addr, sizeof(ia2));
605         if (IN6_IS_SCOPE_LINKLOCAL(&sa->sin6_addr))
606                 ia2.s6_addr16[1] = htons(sa->sin6_scope_id);
607
608         return IN6_ARE_ADDR_EQUAL(ia, &ia2);
609 }
610
611 /*
612  * IPsec output logic for IPv6.
613  */
614 int
615 ipsec6_process_packet(
616         struct mbuf *m,
617         struct ipsecrequest *isr
618     )
619 {
620         struct secasindex saidx;
621         struct secasvar *sav;
622         struct ip6_hdr *ip6;
623         int error, i, off;
624         union sockaddr_union *dst;
625
626         IPSEC_ASSERT(m != NULL, ("ipsec6_process_packet: null mbuf"));
627         IPSEC_ASSERT(isr != NULL, ("ipsec6_process_packet: null isr"));
628
629         IPSECREQUEST_LOCK(isr);         /* insure SA contents don't change */
630
631         isr = ipsec_nextisr(m, isr, AF_INET6, &saidx, &error);
632         if (isr == NULL) {
633                 if (error != 0)
634                         goto bad;
635                 return EJUSTRETURN;
636         }
637
638         sav = isr->sav;
639         dst = &sav->sah->saidx.dst;
640
641 #ifdef DEV_ENC
642         encif->if_opackets++;
643         encif->if_obytes += m->m_pkthdr.len;
644
645         /* pass the mbuf to enc0 for bpf processing */
646         ipsec_bpf(m, isr->sav, AF_INET6, ENC_OUT|ENC_BEFORE);
647         /* pass the mbuf to enc0 for packet filtering */
648         if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_BEFORE)) != 0)
649                 goto bad;
650 #endif /* DEV_ENC */
651
652         ip6 = mtod(m, struct ip6_hdr *); /* XXX */
653
654         /* Do the appropriate encapsulation, if necessary */
655         if (isr->saidx.mode == IPSEC_MODE_TUNNEL || /* Tunnel requ'd */
656             dst->sa.sa_family != AF_INET6 ||        /* PF mismatch */
657             ((dst->sa.sa_family == AF_INET6) &&
658              (!IN6_IS_ADDR_UNSPECIFIED(&dst->sin6.sin6_addr)) &&
659              (!in6_sa_equal_addrwithscope(&dst->sin6,
660                                   &ip6->ip6_dst)))) {
661                 struct mbuf *mp;
662
663                 /* Fix IPv6 header payload length. */
664                 if (m->m_len < sizeof(struct ip6_hdr))
665                         if ((m = m_pullup(m,sizeof(struct ip6_hdr))) == NULL) {
666                                 error = ENOBUFS;
667                                 goto bad;
668                         }
669
670                 if (m->m_pkthdr.len - sizeof(*ip6) > IPV6_MAXPACKET) {
671                         /* No jumbogram support. */
672                         error = ENXIO;   /*XXX*/
673                         goto bad;
674                 }
675
676                 ip6 = mtod(m, struct ip6_hdr *);
677                 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(*ip6));
678
679                 /* Encapsulate the packet */
680                 error = ipip_output(m, isr, &mp, 0, 0);
681                 if (mp == NULL && !error) {
682                         /* Should never happen. */
683                         DPRINTF(("ipsec6_process_packet: ipip_output "
684                                  "returns no mbuf and no error!"));
685                         error = EFAULT;
686                         goto bad;
687                 }
688
689                 if (error) {
690                         if (mp) {
691                                 /* XXX: Should never happen! */
692                                 m_freem(mp);
693                         }
694                         m = NULL; /* ipip_output() already freed it */
695                         goto bad;
696                 }
697
698                 m = mp;
699                 mp = NULL;
700         }
701
702 #ifdef DEV_ENC
703         ipsec_bpf(m, isr->sav, dst->sa.sa_family, ENC_OUT|ENC_AFTER);
704         /* pass the mbuf to enc0 for packet filtering */
705         if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_AFTER)) != 0)
706                 goto bad;
707 #endif /* DEV_ENC */
708
709         switch(dst->sa.sa_family) {
710 #ifdef INET
711         case AF_INET:
712                 {
713                 struct ip *ip;
714                 ip = mtod(m, struct ip *);
715                 i = ip->ip_hl << 2;
716                 off = offsetof(struct ip, ip_p);
717                 }
718                 break;
719 #endif /* AF_INET */
720         case AF_INET6:
721                 i = sizeof(struct ip6_hdr);
722                 off = offsetof(struct ip6_hdr, ip6_nxt);
723                 break;
724         default:
725                 DPRINTF(("%s: unsupported protocol family %u\n",
726                                  __func__, dst->sa.sa_family));
727                 error = EPFNOSUPPORT;
728                 IPSEC6STAT_INC(ips_out_inval);
729                 goto bad;
730         }
731         error = (*sav->tdb_xform->xf_output)(m, isr, NULL, i, off);
732         IPSECREQUEST_UNLOCK(isr);
733         return error;
734 bad:
735
736         if (isr)
737                 IPSECREQUEST_UNLOCK(isr);
738         if (m)
739                 m_freem(m);
740         return error;
741 }
742 #endif /*INET6*/