ipsec_output.c revision 113076
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 113076 2003-04-04 12:56:20Z des $
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#if 0
93	SPLASSERT(net, "ipsec_process_done");
94#endif
95
96	KASSERT(m != NULL, ("ipsec_process_done: null mbuf"));
97	KASSERT(isr != NULL, ("ipsec_process_done: null ISR"));
98	sav = isr->sav;
99	KASSERT(sav != NULL, ("ipsec_process_done: null SA"));
100	KASSERT(sav->sah != NULL, ("ipsec_process_done: null SAH"));
101
102	saidx = &sav->sah->saidx;
103	switch (saidx->dst.sa.sa_family) {
104#ifdef INET
105	case AF_INET:
106		/* Fix the header length, for AH processing. */
107		mtod(m, struct ip *)->ip_len = htons(m->m_pkthdr.len);
108		break;
109#endif /* INET */
110#ifdef INET6
111	case AF_INET6:
112		/* Fix the header length, for AH processing. */
113		if (m->m_pkthdr.len < sizeof (struct ip6_hdr)) {
114			error = ENXIO;
115			goto bad;
116		}
117		if (m->m_pkthdr.len - sizeof (struct ip6_hdr) > IPV6_MAXPACKET) {
118			/* No jumbogram support. */
119			error = ENXIO;	/*?*/
120			goto bad;
121		}
122		mtod(m, struct ip6_hdr *)->ip6_plen =
123			htons(m->m_pkthdr.len - sizeof(struct ip6_hdr));
124		break;
125#endif /* INET6 */
126	default:
127		DPRINTF(("ipsec_process_done: unknown protocol family %u\n",
128		    saidx->dst.sa.sa_family));
129		error = ENXIO;
130		goto bad;
131	}
132
133	/*
134	 * Add a record of what we've done or what needs to be done to the
135	 * packet.
136	 */
137	mtag = m_tag_get(PACKET_TAG_IPSEC_OUT_DONE,
138			sizeof(struct tdb_ident), M_NOWAIT);
139	if (mtag == NULL) {
140		DPRINTF(("ipsec_process_done: could not get packet tag\n"));
141		error = ENOMEM;
142		goto bad;
143	}
144
145	tdbi = (struct tdb_ident *)(mtag + 1);
146	tdbi->dst = saidx->dst;
147	tdbi->proto = saidx->proto;
148	tdbi->spi = sav->spi;
149	m_tag_prepend(m, mtag);
150
151	/*
152	 * If there's another (bundled) SA to apply, do so.
153	 * Note that this puts a burden on the kernel stack size.
154	 * If this is a problem we'll need to introduce a queue
155	 * to set the packet on so we can unwind the stack before
156	 * doing further processing.
157	 */
158	if (isr->next) {
159		newipsecstat.ips_out_bundlesa++;
160		return ipsec4_process_packet(m, isr->next, 0, 0);
161	}
162
163	/*
164	 * We're done with IPsec processing, transmit the packet using the
165	 * appropriate network protocol (IP or IPv6). SPD lookup will be
166	 * performed again there.
167	 */
168	switch (saidx->dst.sa.sa_family) {
169#ifdef INET
170	struct ip *ip;
171	case AF_INET:
172		ip = mtod(m, struct ip *);
173		ip->ip_len = ntohs(ip->ip_len);
174		ip->ip_off = ntohs(ip->ip_off);
175
176		return ip_output(m, NULL, NULL, IP_RAWOUTPUT, NULL, NULL);
177#endif /* INET */
178#ifdef INET6
179	case AF_INET6:
180		/*
181		 * We don't need massage, IPv6 header fields are always in
182		 * net endian.
183		 */
184		return ip6_output(m, NULL, NULL, 0, NULL, NULL, NULL);
185#endif /* INET6 */
186	}
187	panic("ipsec_process_done");
188bad:
189	m_freem(m);
190	KEY_FREESAV(&sav);
191	return (error);
192}
193
194static struct ipsecrequest *
195ipsec_nextisr(
196	struct mbuf *m,
197	struct ipsecrequest *isr,
198	int af,
199	struct secasindex *saidx,
200	int *error
201)
202{
203#define IPSEC_OSTAT(x,y,z) (isr->saidx.proto == IPPROTO_ESP ? (x)++ : \
204			    isr->saidx.proto == IPPROTO_AH ? (y)++ : (z)++)
205	struct secasvar *sav;
206
207#if 0
208	SPLASSERT(net, "ipsec_nextisr");
209#endif
210	KASSERT(af == AF_INET || af == AF_INET6,
211		("ipsec_nextisr: invalid address family %u", af));
212again:
213	/*
214	 * Craft SA index to search for proper SA.  Note that
215	 * we only fillin unspecified SA peers for transport
216	 * mode; for tunnel mode they must already be filled in.
217	 */
218	*saidx = isr->saidx;
219	if (isr->saidx.mode == IPSEC_MODE_TRANSPORT) {
220		/* Fillin unspecified SA peers only for transport mode */
221		if (af == AF_INET) {
222			struct sockaddr_in *sin;
223			struct ip *ip = mtod(m, struct ip *);
224
225			if (saidx->src.sa.sa_len == 0) {
226				sin = &saidx->src.sin;
227				sin->sin_len = sizeof(*sin);
228				sin->sin_family = AF_INET;
229				sin->sin_port = IPSEC_PORT_ANY;
230				sin->sin_addr = ip->ip_src;
231			}
232			if (saidx->dst.sa.sa_len == 0) {
233				sin = &saidx->dst.sin;
234				sin->sin_len = sizeof(*sin);
235				sin->sin_family = AF_INET;
236				sin->sin_port = IPSEC_PORT_ANY;
237				sin->sin_addr = ip->ip_dst;
238			}
239		} else {
240			struct sockaddr_in6 *sin6;
241			struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
242
243			if (saidx->src.sin6.sin6_len == 0) {
244				sin6 = (struct sockaddr_in6 *)&saidx->src;
245				sin6->sin6_len = sizeof(*sin6);
246				sin6->sin6_family = AF_INET6;
247				sin6->sin6_port = IPSEC_PORT_ANY;
248				sin6->sin6_addr = ip6->ip6_src;
249				if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) {
250					/* fix scope id for comparing SPD */
251					sin6->sin6_addr.s6_addr16[1] = 0;
252					sin6->sin6_scope_id =
253					    ntohs(ip6->ip6_src.s6_addr16[1]);
254				}
255			}
256			if (saidx->dst.sin6.sin6_len == 0) {
257				sin6 = (struct sockaddr_in6 *)&saidx->dst;
258				sin6->sin6_len = sizeof(*sin6);
259				sin6->sin6_family = AF_INET6;
260				sin6->sin6_port = IPSEC_PORT_ANY;
261				sin6->sin6_addr = ip6->ip6_dst;
262				if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) {
263					/* fix scope id for comparing SPD */
264					sin6->sin6_addr.s6_addr16[1] = 0;
265					sin6->sin6_scope_id =
266					    ntohs(ip6->ip6_dst.s6_addr16[1]);
267				}
268			}
269		}
270	}
271
272	/*
273	 * Lookup SA and validate it.
274	 */
275	*error = key_checkrequest(isr, saidx);
276	if (*error != 0) {
277		/*
278		 * IPsec processing is required, but no SA found.
279		 * I assume that key_acquire() had been called
280		 * to get/establish the SA. Here I discard
281		 * this packet because it is responsibility for
282		 * upper layer to retransmit the packet.
283		 */
284		newipsecstat.ips_out_nosa++;
285		goto bad;
286	}
287	sav = isr->sav;
288	if (sav == NULL) {		/* XXX valid return */
289		KASSERT(ipsec_get_reqlevel(isr) == IPSEC_LEVEL_USE,
290			("ipsec_nextisr: no SA found, but required; level %u",
291			ipsec_get_reqlevel(isr)));
292		isr = isr->next;
293		if (isr == NULL) {
294			/*XXXstatistic??*/
295			*error = EINVAL;		/*XXX*/
296			return isr;
297		}
298		goto again;
299	}
300
301	/*
302	 * Check system global policy controls.
303	 */
304	if ((isr->saidx.proto == IPPROTO_ESP && !esp_enable) ||
305	    (isr->saidx.proto == IPPROTO_AH && !ah_enable) ||
306	    (isr->saidx.proto == IPPROTO_IPCOMP && !ipcomp_enable)) {
307		DPRINTF(("ipsec_nextisr: IPsec outbound packet dropped due"
308			" to policy (check your sysctls)\n"));
309		IPSEC_OSTAT(espstat.esps_pdrops, ahstat.ahs_pdrops,
310		    ipcompstat.ipcomps_pdrops);
311		*error = EHOSTUNREACH;
312		goto bad;
313	}
314
315	/*
316	 * Sanity check the SA contents for the caller
317	 * before they invoke the xform output method.
318	 */
319	if (sav->tdb_xform == NULL) {
320		DPRINTF(("ipsec_nextisr: no transform for SA\n"));
321		IPSEC_OSTAT(espstat.esps_noxform, ahstat.ahs_noxform,
322		    ipcompstat.ipcomps_noxform);
323		*error = EHOSTUNREACH;
324		goto bad;
325	}
326	return isr;
327bad:
328	KASSERT(*error != 0, ("ipsec_nextisr: error return w/ no error code"));
329	return NULL;
330#undef IPSEC_OSTAT
331}
332
333#ifdef INET
334/*
335 * IPsec output logic for IPv4.
336 */
337int
338ipsec4_process_packet(
339	struct mbuf *m,
340	struct ipsecrequest *isr,
341	int flags,
342	int tunalready)
343{
344	struct secasindex saidx;
345	struct secasvar *sav;
346	struct ip *ip;
347	int s, error, i, off;
348
349	KASSERT(m != NULL, ("ipsec4_process_packet: null mbuf"));
350	KASSERT(isr != NULL, ("ipsec4_process_packet: null isr"));
351
352	s = splnet();			/* insure SA contents don't change */
353
354	isr = ipsec_nextisr(m, isr, AF_INET, &saidx, &error);
355	if (isr == NULL)
356		goto bad;
357
358	sav = isr->sav;
359	if (!tunalready) {
360		union sockaddr_union *dst = &sav->sah->saidx.dst;
361		int setdf;
362
363		/*
364		 * Collect IP_DF state from the outer header.
365		 */
366		if (dst->sa.sa_family == AF_INET) {
367			if (m->m_len < sizeof (struct ip) &&
368			    (m = m_pullup(m, sizeof (struct ip))) == NULL) {
369				error = ENOBUFS;
370				goto bad;
371			}
372			ip = mtod(m, struct ip *);
373			/* Honor system-wide control of how to handle IP_DF */
374			switch (ip4_ipsec_dfbit) {
375			case 0:			/* clear in outer header */
376			case 1:			/* set in outer header */
377				setdf = ip4_ipsec_dfbit;
378				break;
379			default:		/* propagate to outer header */
380				setdf = ntohs(ip->ip_off & IP_DF);
381				break;
382			}
383		} else {
384			ip = NULL;		/* keep compiler happy */
385			setdf = 0;
386		}
387		/* Do the appropriate encapsulation, if necessary */
388		if (isr->saidx.mode == IPSEC_MODE_TUNNEL || /* Tunnel requ'd */
389		    dst->sa.sa_family != AF_INET ||	    /* PF mismatch */
390#if 0
391		    (sav->flags & SADB_X_SAFLAGS_TUNNEL) || /* Tunnel requ'd */
392		    sav->tdb_xform->xf_type == XF_IP4 ||    /* ditto */
393#endif
394		    (dst->sa.sa_family == AF_INET &&	    /* Proxy */
395		     dst->sin.sin_addr.s_addr != INADDR_ANY &&
396		     dst->sin.sin_addr.s_addr != ip->ip_dst.s_addr)) {
397			struct mbuf *mp;
398
399			/* Fix IPv4 header checksum and length */
400			if (m->m_len < sizeof (struct ip) &&
401			    (m = m_pullup(m, sizeof (struct ip))) == NULL) {
402				error = ENOBUFS;
403				goto bad;
404			}
405			ip = mtod(m, struct ip *);
406			ip->ip_len = htons(m->m_pkthdr.len);
407			ip->ip_sum = 0;
408#ifdef _IP_VHL
409			if (ip->ip_vhl == IP_VHL_BORING)
410				ip->ip_sum = in_cksum_hdr(ip);
411			else
412				ip->ip_sum = in_cksum(m,
413					_IP_VHL_HL(ip->ip_vhl) << 2);
414#else
415			ip->ip_sum = in_cksum(m, ip->ip_hl << 2);
416#endif
417
418			/* Encapsulate the packet */
419			error = ipip_output(m, isr, &mp, 0, 0);
420			if (mp == NULL && !error) {
421				/* Should never happen. */
422				DPRINTF(("ipsec4_process_packet: ipip_output "
423					"returns no mbuf and no error!"));
424				error = EFAULT;
425			}
426			if (error) {
427				if (mp)
428					m_freem(mp);
429				goto bad;
430			}
431			m = mp, mp = NULL;
432			/*
433			 * ipip_output clears IP_DF in the new header.  If
434			 * we need to propagate IP_DF from the outer header,
435			 * then we have to do it here.
436			 *
437			 * XXX shouldn't assume what ipip_output does.
438			 */
439			if (dst->sa.sa_family == AF_INET && setdf) {
440				if (m->m_len < sizeof (struct ip) &&
441				    (m = m_pullup(m, sizeof (struct ip))) == NULL) {
442					error = ENOBUFS;
443					goto bad;
444				}
445				ip = mtod(m, struct ip *);
446				ip->ip_off = ntohs(ip->ip_off);
447				ip->ip_off |= IP_DF;
448				ip->ip_off = htons(ip->ip_off);
449			}
450		}
451	}
452
453	/*
454	 * Dispatch to the appropriate IPsec transform logic.  The
455	 * packet will be returned for transmission after crypto
456	 * processing, etc. are completed.  For encapsulation we
457	 * bypass this call because of the explicit call done above
458	 * (necessary to deal with IP_DF handling for IPv4).
459	 *
460	 * NB: m & sav are ``passed to caller'' who's reponsible for
461	 *     for reclaiming their resources.
462	 */
463	if (sav->tdb_xform->xf_type != XF_IP4) {
464		ip = mtod(m, struct ip *);
465		i = ip->ip_hl << 2;
466		off = offsetof(struct ip, ip_p);
467		error = (*sav->tdb_xform->xf_output)(m, isr, NULL, i, off);
468	} else {
469		error = ipsec_process_done(m, isr);
470	}
471	splx(s);
472	return error;
473bad:
474	splx(s);
475	if (m)
476		m_freem(m);
477	return error;
478}
479#endif
480
481#ifdef INET6
482/*
483 * Chop IP6 header from the payload.
484 */
485static struct mbuf *
486ipsec6_splithdr(struct mbuf *m)
487{
488	struct mbuf *mh;
489	struct ip6_hdr *ip6;
490	int hlen;
491
492	KASSERT(m->m_len >= sizeof (struct ip6_hdr),
493		("ipsec6_splithdr: first mbuf too short, len %u", m->m_len));
494	ip6 = mtod(m, struct ip6_hdr *);
495	hlen = sizeof(struct ip6_hdr);
496	if (m->m_len > hlen) {
497		MGETHDR(mh, M_DONTWAIT, MT_HEADER);
498		if (!mh) {
499			m_freem(m);
500			return NULL;
501		}
502		M_MOVE_PKTHDR(mh, m);
503		MH_ALIGN(mh, hlen);
504		m->m_len -= hlen;
505		m->m_data += hlen;
506		mh->m_next = m;
507		m = mh;
508		m->m_len = hlen;
509		bcopy((caddr_t)ip6, mtod(m, caddr_t), hlen);
510	} else if (m->m_len < hlen) {
511		m = m_pullup(m, hlen);
512		if (!m)
513			return NULL;
514	}
515	return m;
516}
517
518/*
519 * IPsec output logic for IPv6, transport mode.
520 */
521int
522ipsec6_output_trans(
523	struct ipsec_output_state *state,
524	u_char *nexthdrp,
525	struct mbuf *mprev,
526	struct secpolicy *sp,
527	int flags,
528	int *tun)
529{
530	struct ipsecrequest *isr;
531	struct secasindex saidx;
532	int error = 0;
533	struct mbuf *m;
534
535	KASSERT(state != NULL, ("ipsec6_output: null state"));
536	KASSERT(state->m != NULL, ("ipsec6_output: null m"));
537	KASSERT(nexthdrp != NULL, ("ipsec6_output: null nexthdrp"));
538	KASSERT(mprev != NULL, ("ipsec6_output: null mprev"));
539	KASSERT(sp != NULL, ("ipsec6_output: null sp"));
540	KASSERT(tun != NULL, ("ipsec6_output: null tun"));
541
542	KEYDEBUG(KEYDEBUG_IPSEC_DATA,
543		printf("ipsec6_output_trans: applyed SP\n");
544		kdebug_secpolicy(sp));
545
546	isr = sp->req;
547	if (isr->saidx.mode == IPSEC_MODE_TUNNEL) {
548		/* the rest will be handled by ipsec6_output_tunnel() */
549		*tun = 1;		/* need tunnel-mode processing */
550		return 0;
551	}
552
553	*tun = 0;
554	m = state->m;
555
556	isr = ipsec_nextisr(m, isr, AF_INET6, &saidx, &error);
557	if (isr == NULL) {
558#ifdef notdef
559		/* XXX should notification be done for all errors ? */
560		/*
561		 * Notify the fact that the packet is discarded
562		 * to ourselves. I believe this is better than
563		 * just silently discarding. (jinmei@kame.net)
564		 * XXX: should we restrict the error to TCP packets?
565		 * XXX: should we directly notify sockets via
566		 *      pfctlinputs?
567		 */
568		icmp6_error(m, ICMP6_DST_UNREACH,
569			    ICMP6_DST_UNREACH_ADMIN, 0);
570		m = NULL;	/* NB: icmp6_error frees mbuf */
571#endif
572		goto bad;
573	}
574
575	return (*isr->sav->tdb_xform->xf_output)(m, isr, NULL,
576		sizeof (struct ip6_hdr),
577		offsetof(struct ip6_hdr, ip6_nxt));
578bad:
579	if (m)
580		m_freem(m);
581	state->m = NULL;
582	return error;
583}
584
585static int
586ipsec6_encapsulate(struct mbuf *m, struct secasvar *sav)
587{
588	struct ip6_hdr *oip6;
589	struct ip6_hdr *ip6;
590	size_t plen;
591
592	/* can't tunnel between different AFs */
593	if (sav->sah->saidx.src.sa.sa_family != AF_INET6 ||
594	    sav->sah->saidx.dst.sa.sa_family != AF_INET6) {
595		m_freem(m);
596		return EINVAL;
597	}
598	KASSERT(m->m_len != sizeof (struct ip6_hdr),
599		("ipsec6_encapsulate: mbuf wrong size; len %u", m->m_len));
600
601
602	/*
603	 * grow the mbuf to accomodate the new IPv6 header.
604	 */
605	plen = m->m_pkthdr.len;
606	if (M_LEADINGSPACE(m->m_next) < sizeof(struct ip6_hdr)) {
607		struct mbuf *n;
608		MGET(n, M_DONTWAIT, MT_DATA);
609		if (!n) {
610			m_freem(m);
611			return ENOBUFS;
612		}
613		n->m_len = sizeof(struct ip6_hdr);
614		n->m_next = m->m_next;
615		m->m_next = n;
616		m->m_pkthdr.len += sizeof(struct ip6_hdr);
617		oip6 = mtod(n, struct ip6_hdr *);
618	} else {
619		m->m_next->m_len += sizeof(struct ip6_hdr);
620		m->m_next->m_data -= sizeof(struct ip6_hdr);
621		m->m_pkthdr.len += sizeof(struct ip6_hdr);
622		oip6 = mtod(m->m_next, struct ip6_hdr *);
623	}
624	ip6 = mtod(m, struct ip6_hdr *);
625	bcopy((caddr_t)ip6, (caddr_t)oip6, sizeof(struct ip6_hdr));
626
627	/* Fake link-local scope-class addresses */
628	if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_src))
629		oip6->ip6_src.s6_addr16[1] = 0;
630	if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_dst))
631		oip6->ip6_dst.s6_addr16[1] = 0;
632
633	/* construct new IPv6 header. see RFC 2401 5.1.2.2 */
634	/* ECN consideration. */
635	ip6_ecn_ingress(ip6_ipsec_ecn, &ip6->ip6_flow, &oip6->ip6_flow);
636	if (plen < IPV6_MAXPACKET - sizeof(struct ip6_hdr))
637		ip6->ip6_plen = htons(plen);
638	else {
639		/* ip6->ip6_plen will be updated in ip6_output() */
640	}
641	ip6->ip6_nxt = IPPROTO_IPV6;
642	sav->sah->saidx.src.sin6.sin6_addr = ip6->ip6_src;
643	sav->sah->saidx.dst.sin6.sin6_addr = ip6->ip6_dst;
644	ip6->ip6_hlim = IPV6_DEFHLIM;
645
646	/* XXX Should ip6_src be updated later ? */
647
648	return 0;
649}
650
651/*
652 * IPsec output logic for IPv6, tunnel mode.
653 */
654int
655ipsec6_output_tunnel(struct ipsec_output_state *state, struct secpolicy *sp, int flags)
656{
657	struct ip6_hdr *ip6;
658	struct ipsecrequest *isr;
659	struct secasindex saidx;
660	int error;
661	struct sockaddr_in6* dst6;
662	struct mbuf *m;
663
664	KASSERT(state != NULL, ("ipsec6_output: null state"));
665	KASSERT(state->m != NULL, ("ipsec6_output: null m"));
666	KASSERT(sp != NULL, ("ipsec6_output: null sp"));
667
668	KEYDEBUG(KEYDEBUG_IPSEC_DATA,
669		printf("ipsec6_output_tunnel: applyed SP\n");
670		kdebug_secpolicy(sp));
671
672	m = state->m;
673	/*
674	 * transport mode ipsec (before the 1st tunnel mode) is already
675	 * processed by ipsec6_output_trans().
676	 */
677	for (isr = sp->req; isr; isr = isr->next) {
678		if (isr->saidx.mode == IPSEC_MODE_TUNNEL)
679			break;
680	}
681	isr = ipsec_nextisr(m, isr, AF_INET6, &saidx, &error);
682	if (isr == NULL)
683		goto bad;
684
685	/*
686	 * There may be the case that SA status will be changed when
687	 * we are refering to one. So calling splsoftnet().
688	 */
689	if (isr->saidx.mode == IPSEC_MODE_TUNNEL) {
690		/*
691		 * build IPsec tunnel.
692		 */
693		/* XXX should be processed with other familiy */
694		if (isr->sav->sah->saidx.src.sa.sa_family != AF_INET6) {
695			ipseclog((LOG_ERR, "ipsec6_output_tunnel: "
696			    "family mismatched between inner and outer, spi=%u\n",
697			    ntohl(isr->sav->spi)));
698			newipsecstat.ips_out_inval++;
699			error = EAFNOSUPPORT;
700			goto bad;
701		}
702
703		m = ipsec6_splithdr(m);
704		if (!m) {
705			newipsecstat.ips_out_nomem++;
706			error = ENOMEM;
707			goto bad;
708		}
709		error = ipsec6_encapsulate(m, isr->sav);
710		if (error) {
711			m = NULL;
712			goto bad;
713		}
714		ip6 = mtod(m, struct ip6_hdr *);
715
716		state->ro = &isr->sav->sah->sa_route;
717		state->dst = (struct sockaddr *)&state->ro->ro_dst;
718		dst6 = (struct sockaddr_in6 *)state->dst;
719		if (state->ro->ro_rt
720		 && ((state->ro->ro_rt->rt_flags & RTF_UP) == 0
721		  || !IN6_ARE_ADDR_EQUAL(&dst6->sin6_addr, &ip6->ip6_dst))) {
722			RTFREE(state->ro->ro_rt);
723			state->ro->ro_rt = NULL;
724		}
725		if (state->ro->ro_rt == 0) {
726			bzero(dst6, sizeof(*dst6));
727			dst6->sin6_family = AF_INET6;
728			dst6->sin6_len = sizeof(*dst6);
729			dst6->sin6_addr = ip6->ip6_dst;
730			rtalloc(state->ro);
731		}
732		if (state->ro->ro_rt == 0) {
733			ip6stat.ip6s_noroute++;
734			newipsecstat.ips_out_noroute++;
735			error = EHOSTUNREACH;
736			goto bad;
737		}
738
739		/* adjust state->dst if tunnel endpoint is offlink */
740		if (state->ro->ro_rt->rt_flags & RTF_GATEWAY) {
741			state->dst = (struct sockaddr *)state->ro->ro_rt->rt_gateway;
742			dst6 = (struct sockaddr_in6 *)state->dst;
743		}
744	}
745
746	m = ipsec6_splithdr(m);
747	if (!m) {
748		newipsecstat.ips_out_nomem++;
749		error = ENOMEM;
750		goto bad;
751	}
752	ip6 = mtod(m, struct ip6_hdr *);
753	return (*isr->sav->tdb_xform->xf_output)(m, isr, NULL,
754		sizeof (struct ip6_hdr),
755		offsetof(struct ip6_hdr, ip6_nxt));
756bad:
757	if (m)
758		m_freem(m);
759	state->m = NULL;
760	return error;
761}
762#endif /*INET6*/
763