ipsec_output.c revision 282139
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 282139 2015-04-28 11:03:47Z ae $
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/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#include <netinet6/scope6_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
96int
97ipsec_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	IPSEC_ASSERT(isr->sp != NULL, ("NULL isr->sp"));
108	sav = isr->sav;
109	IPSEC_ASSERT(sav != NULL, ("null SA"));
110	IPSEC_ASSERT(sav->sah != NULL, ("null SAH"));
111
112	saidx = &sav->sah->saidx;
113	switch (saidx->dst.sa.sa_family) {
114#ifdef INET
115	case AF_INET:
116		/* Fix the header length, for AH processing. */
117		mtod(m, struct ip *)->ip_len = htons(m->m_pkthdr.len);
118		break;
119#endif /* INET */
120#ifdef INET6
121	case AF_INET6:
122		/* Fix the header length, for AH processing. */
123		if (m->m_pkthdr.len < sizeof (struct ip6_hdr)) {
124			error = ENXIO;
125			goto bad;
126		}
127		if (m->m_pkthdr.len - sizeof (struct ip6_hdr) > IPV6_MAXPACKET) {
128			/* No jumbogram support. */
129			error = ENXIO;	/*?*/
130			goto bad;
131		}
132		mtod(m, struct ip6_hdr *)->ip6_plen =
133			htons(m->m_pkthdr.len - sizeof(struct ip6_hdr));
134		break;
135#endif /* INET6 */
136	default:
137		DPRINTF(("%s: unknown protocol family %u\n", __func__,
138		    saidx->dst.sa.sa_family));
139		error = ENXIO;
140		goto bad;
141	}
142
143	/*
144	 * Add a record of what we've done or what needs to be done to the
145	 * packet.
146	 */
147	mtag = m_tag_get(PACKET_TAG_IPSEC_OUT_DONE,
148			sizeof(struct tdb_ident), M_NOWAIT);
149	if (mtag == NULL) {
150		DPRINTF(("%s: could not get packet tag\n", __func__));
151		error = ENOMEM;
152		goto bad;
153	}
154
155	tdbi = (struct tdb_ident *)(mtag + 1);
156	tdbi->dst = saidx->dst;
157	tdbi->proto = saidx->proto;
158	tdbi->spi = sav->spi;
159	m_tag_prepend(m, mtag);
160
161	/*
162	 * If there's another (bundled) SA to apply, do so.
163	 * Note that this puts a burden on the kernel stack size.
164	 * If this is a problem we'll need to introduce a queue
165	 * to set the packet on so we can unwind the stack before
166	 * doing further processing.
167	 *
168	 * If ipsec[46]_process_packet() will successfully queue
169	 * the request, we need to take additional reference to SP,
170	 * because xform callback will release reference.
171	 */
172	if (isr->next) {
173		/* XXX-BZ currently only support same AF bundles. */
174		switch (saidx->dst.sa.sa_family) {
175#ifdef INET
176		case AF_INET:
177			IPSECSTAT_INC(ips_out_bundlesa);
178			key_addref(isr->sp);
179			error = ipsec4_process_packet(m, isr->next);
180			if (error != 0)
181				KEY_FREESP(&isr->sp);
182			return (error);
183			/* NOTREACHED */
184#endif
185#ifdef notyet
186#ifdef INET6
187		case AF_INET6:
188			/* XXX */
189			IPSEC6STAT_INC(ips_out_bundlesa);
190			key_addref(isr->sp);
191			error = ipsec6_process_packet(m, isr->next);
192			if (error != 0)
193				KEY_FREESP(&isr->sp);
194			return (error);
195			/* NOTREACHED */
196#endif /* INET6 */
197#endif
198		default:
199			DPRINTF(("%s: unknown protocol family %u\n", __func__,
200			    saidx->dst.sa.sa_family));
201			error = ENXIO;
202			goto bad;
203		}
204	}
205	key_sa_recordxfer(sav, m);		/* record data transfer */
206
207	/*
208	 * We're done with IPsec processing, transmit the packet using the
209	 * appropriate network protocol (IP or IPv6).
210	 */
211	switch (saidx->dst.sa.sa_family) {
212#ifdef INET
213	case AF_INET:
214#ifdef IPSEC_NAT_T
215		/*
216		 * If NAT-T is enabled, now that all IPsec processing is done
217		 * insert UDP encapsulation header after IP header.
218		 */
219		if (sav->natt_type) {
220			struct ip *ip = mtod(m, struct ip *);
221			const int hlen = (ip->ip_hl << 2);
222			int size, off;
223			struct mbuf *mi;
224			struct udphdr *udp;
225
226			size = sizeof(struct udphdr);
227			if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE) {
228				/*
229				 * draft-ietf-ipsec-nat-t-ike-0[01].txt and
230				 * draft-ietf-ipsec-udp-encaps-(00/)01.txt,
231				 * ignoring possible AH mode
232				 * non-IKE marker + non-ESP marker
233				 * from draft-ietf-ipsec-udp-encaps-00.txt.
234				 */
235				size += sizeof(u_int64_t);
236			}
237			mi = m_makespace(m, hlen, size, &off);
238			if (mi == NULL) {
239				DPRINTF(("%s: m_makespace for udphdr failed\n",
240				    __func__));
241				error = ENOBUFS;
242				goto bad;
243			}
244
245			udp = (struct udphdr *)(mtod(mi, caddr_t) + off);
246			if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE)
247				udp->uh_sport = htons(UDP_ENCAP_ESPINUDP_PORT);
248			else
249				udp->uh_sport =
250					KEY_PORTFROMSADDR(&sav->sah->saidx.src);
251			udp->uh_dport = KEY_PORTFROMSADDR(&sav->sah->saidx.dst);
252			udp->uh_sum = 0;
253			udp->uh_ulen = htons(m->m_pkthdr.len - hlen);
254			ip->ip_len = htons(m->m_pkthdr.len);
255			ip->ip_p = IPPROTO_UDP;
256
257			if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE)
258				*(u_int64_t *)(udp + 1) = 0;
259		}
260#endif /* IPSEC_NAT_T */
261
262		return ip_output(m, NULL, NULL, IP_RAWOUTPUT, NULL, NULL);
263#endif /* INET */
264#ifdef INET6
265	case AF_INET6:
266		/*
267		 * We don't need massage, IPv6 header fields are always in
268		 * net endian.
269		 */
270		return ip6_output(m, NULL, NULL, 0, NULL, NULL, NULL);
271#endif /* INET6 */
272	}
273	panic("ipsec_process_done");
274bad:
275	m_freem(m);
276	return (error);
277}
278
279static struct ipsecrequest *
280ipsec_nextisr(
281	struct mbuf *m,
282	struct ipsecrequest *isr,
283	int af,
284	struct secasindex *saidx,
285	int *error
286)
287{
288#define	IPSEC_OSTAT(name)	do {		\
289	if (isr->saidx.proto == IPPROTO_ESP)	\
290		ESPSTAT_INC(esps_##name);	\
291	else if (isr->saidx.proto == IPPROTO_AH)\
292		AHSTAT_INC(ahs_##name);		\
293	else					\
294		IPCOMPSTAT_INC(ipcomps_##name);	\
295} while (0)
296	struct secasvar *sav;
297
298	IPSECREQUEST_LOCK_ASSERT(isr);
299
300	IPSEC_ASSERT(af == AF_INET || af == AF_INET6,
301		("invalid address family %u", af));
302again:
303	/*
304	 * Craft SA index to search for proper SA.  Note that
305	 * we only fillin unspecified SA peers for transport
306	 * mode; for tunnel mode they must already be filled in.
307	 */
308	*saidx = isr->saidx;
309	if (isr->saidx.mode == IPSEC_MODE_TRANSPORT) {
310		/* Fillin unspecified SA peers only for transport mode */
311		if (af == AF_INET) {
312			struct sockaddr_in *sin;
313			struct ip *ip = mtod(m, struct ip *);
314
315			if (saidx->src.sa.sa_len == 0) {
316				sin = &saidx->src.sin;
317				sin->sin_len = sizeof(*sin);
318				sin->sin_family = AF_INET;
319				sin->sin_port = IPSEC_PORT_ANY;
320				sin->sin_addr = ip->ip_src;
321			}
322			if (saidx->dst.sa.sa_len == 0) {
323				sin = &saidx->dst.sin;
324				sin->sin_len = sizeof(*sin);
325				sin->sin_family = AF_INET;
326				sin->sin_port = IPSEC_PORT_ANY;
327				sin->sin_addr = ip->ip_dst;
328			}
329		} else {
330			struct sockaddr_in6 *sin6;
331			struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
332
333			if (saidx->src.sin6.sin6_len == 0) {
334				sin6 = (struct sockaddr_in6 *)&saidx->src;
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_src;
339				if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) {
340					/* fix scope id for comparing SPD */
341					sin6->sin6_addr.s6_addr16[1] = 0;
342					sin6->sin6_scope_id =
343					    ntohs(ip6->ip6_src.s6_addr16[1]);
344				}
345			}
346			if (saidx->dst.sin6.sin6_len == 0) {
347				sin6 = (struct sockaddr_in6 *)&saidx->dst;
348				sin6->sin6_len = sizeof(*sin6);
349				sin6->sin6_family = AF_INET6;
350				sin6->sin6_port = IPSEC_PORT_ANY;
351				sin6->sin6_addr = ip6->ip6_dst;
352				if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) {
353					/* fix scope id for comparing SPD */
354					sin6->sin6_addr.s6_addr16[1] = 0;
355					sin6->sin6_scope_id =
356					    ntohs(ip6->ip6_dst.s6_addr16[1]);
357				}
358			}
359		}
360	}
361
362	/*
363	 * Lookup SA and validate it.
364	 */
365	*error = key_checkrequest(isr, saidx);
366	if (*error != 0) {
367		/*
368		 * IPsec processing is required, but no SA found.
369		 * I assume that key_acquire() had been called
370		 * to get/establish the SA. Here I discard
371		 * this packet because it is responsibility for
372		 * upper layer to retransmit the packet.
373		 */
374		switch(af) {
375		case AF_INET:
376			IPSECSTAT_INC(ips_out_nosa);
377			break;
378#ifdef INET6
379		case AF_INET6:
380			IPSEC6STAT_INC(ips_out_nosa);
381			break;
382#endif
383		}
384		goto bad;
385	}
386	sav = isr->sav;
387	if (sav == NULL) {
388		IPSEC_ASSERT(ipsec_get_reqlevel(isr) == IPSEC_LEVEL_USE,
389			("no SA found, but required; level %u",
390			ipsec_get_reqlevel(isr)));
391		IPSECREQUEST_UNLOCK(isr);
392		isr = isr->next;
393		/*
394		 * If isr is NULL, we found a 'use' policy w/o SA.
395		 * Return w/o error and w/o isr so we can drop out
396		 * and continue w/o IPsec processing.
397		 */
398		if (isr == NULL)
399			return isr;
400		IPSECREQUEST_LOCK(isr);
401		goto again;
402	}
403
404	/*
405	 * Check system global policy controls.
406	 */
407	if ((isr->saidx.proto == IPPROTO_ESP && !V_esp_enable) ||
408	    (isr->saidx.proto == IPPROTO_AH && !V_ah_enable) ||
409	    (isr->saidx.proto == IPPROTO_IPCOMP && !V_ipcomp_enable)) {
410		DPRINTF(("%s: IPsec outbound packet dropped due"
411			" to policy (check your sysctls)\n", __func__));
412		IPSEC_OSTAT(pdrops);
413		*error = EHOSTUNREACH;
414		goto bad;
415	}
416
417	/*
418	 * Sanity check the SA contents for the caller
419	 * before they invoke the xform output method.
420	 */
421	if (sav->tdb_xform == NULL) {
422		DPRINTF(("%s: no transform for SA\n", __func__));
423		IPSEC_OSTAT(noxform);
424		*error = EHOSTUNREACH;
425		goto bad;
426	}
427	return isr;
428bad:
429	IPSEC_ASSERT(*error != 0, ("error return w/ no error code"));
430	IPSECREQUEST_UNLOCK(isr);
431	return NULL;
432#undef IPSEC_OSTAT
433}
434
435static int
436ipsec_encap(struct mbuf **mp, struct secasindex *saidx)
437{
438#ifdef INET6
439	struct ip6_hdr *ip6;
440#endif
441	struct ip *ip;
442	int setdf;
443	uint8_t itos, proto;
444
445	ip = mtod(*mp, struct ip *);
446	switch (ip->ip_v) {
447#ifdef INET
448	case IPVERSION:
449		proto = IPPROTO_IPIP;
450		/*
451		 * Collect IP_DF state from the inner header
452		 * and honor system-wide control of how to handle it.
453		 */
454		switch (V_ip4_ipsec_dfbit) {
455		case 0:	/* clear in outer header */
456		case 1:	/* set in outer header */
457			setdf = V_ip4_ipsec_dfbit;
458			break;
459		default:/* propagate to outer header */
460			setdf = (ip->ip_off & ntohs(IP_DF)) != 0;
461		}
462		itos = ip->ip_tos;
463		break;
464#endif
465#ifdef INET6
466	case (IPV6_VERSION >> 4):
467		proto = IPPROTO_IPV6;
468		ip6 = mtod(*mp, struct ip6_hdr *);
469		itos = (ntohl(ip6->ip6_flow) >> 20) & 0xff;
470		setdf = V_ip4_ipsec_dfbit ? 1: 0;
471		/* scoped address handling */
472		in6_clearscope(&ip6->ip6_src);
473		in6_clearscope(&ip6->ip6_dst);
474		break;
475#endif
476	default:
477		return (EAFNOSUPPORT);
478	}
479	switch (saidx->dst.sa.sa_family) {
480#ifdef INET
481	case AF_INET:
482		if (saidx->src.sa.sa_family != AF_INET ||
483		    saidx->src.sin.sin_addr.s_addr == INADDR_ANY ||
484		    saidx->dst.sin.sin_addr.s_addr == INADDR_ANY)
485			return (EINVAL);
486		M_PREPEND(*mp, sizeof(struct ip), M_NOWAIT);
487		if (*mp == NULL)
488			return (ENOBUFS);
489		ip = mtod(*mp, struct ip *);
490		ip->ip_v = IPVERSION;
491		ip->ip_hl = sizeof(struct ip) >> 2;
492		ip->ip_p = proto;
493		ip->ip_len = htons((*mp)->m_pkthdr.len);
494		ip->ip_ttl = V_ip_defttl;
495		ip->ip_sum = 0;
496		ip->ip_off = setdf ? htons(IP_DF): 0;
497		ip->ip_src = saidx->src.sin.sin_addr;
498		ip->ip_dst = saidx->dst.sin.sin_addr;
499		ip_ecn_ingress(V_ip4_ipsec_ecn, &ip->ip_tos, &itos);
500		ip_fillid(ip);
501		break;
502#endif /* INET */
503#ifdef INET6
504	case AF_INET6:
505		if (saidx->src.sa.sa_family != AF_INET6 ||
506		    IN6_IS_ADDR_UNSPECIFIED(&saidx->src.sin6.sin6_addr) ||
507		    IN6_IS_ADDR_UNSPECIFIED(&saidx->dst.sin6.sin6_addr))
508			return (EINVAL);
509		M_PREPEND(*mp, sizeof(struct ip6_hdr), M_NOWAIT);
510		if (*mp == NULL)
511			return (ENOBUFS);
512		ip6 = mtod(*mp, struct ip6_hdr *);
513		ip6->ip6_flow = 0;
514		ip6->ip6_vfc = IPV6_VERSION;
515		ip6->ip6_hlim = V_ip6_defhlim;
516		ip6->ip6_nxt = proto;
517		ip6->ip6_dst = saidx->dst.sin6.sin6_addr;
518		/* For link-local address embed scope zone id */
519		if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst))
520			ip6->ip6_dst.s6_addr16[1] =
521			    htons(saidx->dst.sin6.sin6_scope_id & 0xffff);
522		ip6->ip6_src = saidx->src.sin6.sin6_addr;
523		if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src))
524			ip6->ip6_src.s6_addr16[1] =
525			    htons(saidx->src.sin6.sin6_scope_id & 0xffff);
526		ip6->ip6_plen = htons((*mp)->m_pkthdr.len - sizeof(*ip6));
527		ip_ecn_ingress(V_ip6_ipsec_ecn, &proto, &itos);
528		ip6->ip6_flow |= htonl((uint32_t)proto << 20);
529		break;
530#endif /* INET6 */
531	default:
532		return (EAFNOSUPPORT);
533	}
534	return (0);
535}
536
537#ifdef INET
538/*
539 * IPsec output logic for IPv4.
540 */
541int
542ipsec4_process_packet(struct mbuf *m, struct ipsecrequest *isr)
543{
544	char sbuf[INET6_ADDRSTRLEN], dbuf[INET6_ADDRSTRLEN];
545	union sockaddr_union *dst;
546	struct secasindex saidx;
547	struct secasvar *sav;
548	struct ip *ip;
549	int error, i, off;
550
551	IPSEC_ASSERT(m != NULL, ("null mbuf"));
552	IPSEC_ASSERT(isr != NULL, ("null isr"));
553
554	IPSECREQUEST_LOCK(isr);		/* insure SA contents don't change */
555
556	isr = ipsec_nextisr(m, isr, AF_INET, &saidx, &error);
557	if (isr == NULL) {
558		if (error != 0)
559			goto bad;
560		return EJUSTRETURN;
561	}
562
563	sav = isr->sav;
564	if (m->m_len < sizeof(struct ip) &&
565	    (m = m_pullup(m, sizeof (struct ip))) == NULL) {
566		error = ENOBUFS;
567		goto bad;
568	}
569	ip = mtod(m, struct ip *);
570	dst = &sav->sah->saidx.dst;
571#ifdef DEV_ENC
572	if_inc_counter(encif, IFCOUNTER_OPACKETS, 1);
573	if_inc_counter(encif, IFCOUNTER_OBYTES, m->m_pkthdr.len);
574
575	/* pass the mbuf to enc0 for bpf processing */
576	ipsec_bpf(m, sav, AF_INET, ENC_OUT|ENC_BEFORE);
577	/* pass the mbuf to enc0 for packet filtering */
578	if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_BEFORE)) != 0)
579		goto bad;
580	ip = mtod(m, struct ip *);
581#endif
582	/* Do the appropriate encapsulation, if necessary */
583	if (isr->saidx.mode == IPSEC_MODE_TUNNEL || /* Tunnel requ'd */
584	    dst->sa.sa_family != AF_INET ||	    /* PF mismatch */
585	    (dst->sa.sa_family == AF_INET &&	    /* Proxy */
586	     dst->sin.sin_addr.s_addr != INADDR_ANY &&
587	     dst->sin.sin_addr.s_addr != ip->ip_dst.s_addr)) {
588		/* Fix IPv4 header checksum and length */
589		ip->ip_len = htons(m->m_pkthdr.len);
590		ip->ip_sum = 0;
591		ip->ip_sum = in_cksum(m, ip->ip_hl << 2);
592		error = ipsec_encap(&m, &sav->sah->saidx);
593		if (error != 0) {
594			DPRINTF(("%s: encapsulation for SA %s->%s "
595			    "SPI 0x%08x failed with error %d\n", __func__,
596			    ipsec_address(&sav->sah->saidx.src, sbuf,
597				sizeof(sbuf)),
598			    ipsec_address(&sav->sah->saidx.dst, dbuf,
599				sizeof(dbuf)), ntohl(sav->spi), error));
600			goto bad;
601		}
602	}
603#ifdef DEV_ENC
604	/* pass the mbuf to enc0 for bpf processing */
605	ipsec_bpf(m, sav, sav->sah->saidx.dst.sa.sa_family, ENC_OUT|ENC_AFTER);
606	/* pass the mbuf to enc0 for packet filtering */
607	if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_AFTER)) != 0)
608		goto bad;
609#endif
610
611	/*
612	 * Dispatch to the appropriate IPsec transform logic.  The
613	 * packet will be returned for transmission after crypto
614	 * processing, etc. are completed.
615	 *
616	 * NB: m & sav are ``passed to caller'' who's reponsible for
617	 *     for reclaiming their resources.
618	 */
619	switch(dst->sa.sa_family) {
620	case AF_INET:
621		ip = mtod(m, struct ip *);
622		i = ip->ip_hl << 2;
623		off = offsetof(struct ip, ip_p);
624		break;
625#ifdef INET6
626	case AF_INET6:
627		i = sizeof(struct ip6_hdr);
628		off = offsetof(struct ip6_hdr, ip6_nxt);
629		break;
630#endif /* INET6 */
631	default:
632		DPRINTF(("%s: unsupported protocol family %u\n",
633		    __func__, dst->sa.sa_family));
634		error = EPFNOSUPPORT;
635		IPSECSTAT_INC(ips_out_inval);
636		goto bad;
637	}
638	error = (*sav->tdb_xform->xf_output)(m, isr, NULL, i, off);
639	IPSECREQUEST_UNLOCK(isr);
640	return (error);
641bad:
642	if (isr)
643		IPSECREQUEST_UNLOCK(isr);
644	if (m)
645		m_freem(m);
646	return error;
647}
648#endif
649
650
651#ifdef INET6
652static int
653in6_sa_equal_addrwithscope(const struct sockaddr_in6 *sa, const struct in6_addr *ia)
654{
655	struct in6_addr ia2;
656
657	memcpy(&ia2, &sa->sin6_addr, sizeof(ia2));
658	if (IN6_IS_SCOPE_LINKLOCAL(&sa->sin6_addr))
659		ia2.s6_addr16[1] = htons(sa->sin6_scope_id);
660
661	return IN6_ARE_ADDR_EQUAL(ia, &ia2);
662}
663
664/*
665 * IPsec output logic for IPv6.
666 */
667int
668ipsec6_process_packet(struct mbuf *m, struct ipsecrequest *isr)
669{
670	char sbuf[INET6_ADDRSTRLEN], dbuf[INET6_ADDRSTRLEN];
671	struct secasindex saidx;
672	struct secasvar *sav;
673	struct ip6_hdr *ip6;
674	int error, i, off;
675	union sockaddr_union *dst;
676
677	IPSEC_ASSERT(m != NULL, ("ipsec6_process_packet: null mbuf"));
678	IPSEC_ASSERT(isr != NULL, ("ipsec6_process_packet: null isr"));
679
680	IPSECREQUEST_LOCK(isr);		/* insure SA contents don't change */
681
682	isr = ipsec_nextisr(m, isr, AF_INET6, &saidx, &error);
683	if (isr == NULL) {
684		if (error != 0)
685			goto bad;
686		return EJUSTRETURN;
687	}
688	sav = isr->sav;
689	dst = &sav->sah->saidx.dst;
690
691	ip6 = mtod(m, struct ip6_hdr *);
692	ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(*ip6));
693#ifdef DEV_ENC
694	if_inc_counter(encif, IFCOUNTER_OPACKETS, 1);
695	if_inc_counter(encif, IFCOUNTER_OBYTES, m->m_pkthdr.len);
696
697	/* pass the mbuf to enc0 for bpf processing */
698	ipsec_bpf(m, isr->sav, AF_INET6, ENC_OUT|ENC_BEFORE);
699	/* pass the mbuf to enc0 for packet filtering */
700	if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_BEFORE)) != 0)
701		goto bad;
702	ip6 = mtod(m, struct ip6_hdr *);
703#endif /* DEV_ENC */
704
705	/* Do the appropriate encapsulation, if necessary */
706	if (isr->saidx.mode == IPSEC_MODE_TUNNEL || /* Tunnel requ'd */
707	    dst->sa.sa_family != AF_INET6 ||        /* PF mismatch */
708	    ((dst->sa.sa_family == AF_INET6) &&
709	     (!IN6_IS_ADDR_UNSPECIFIED(&dst->sin6.sin6_addr)) &&
710	     (!in6_sa_equal_addrwithscope(&dst->sin6,
711				  &ip6->ip6_dst)))) {
712		if (m->m_pkthdr.len - sizeof(*ip6) > IPV6_MAXPACKET) {
713			/* No jumbogram support. */
714			error = ENXIO;   /*XXX*/
715			goto bad;
716		}
717		error = ipsec_encap(&m, &sav->sah->saidx);
718		if (error != 0) {
719			DPRINTF(("%s: encapsulation for SA %s->%s "
720			    "SPI 0x%08x failed with error %d\n", __func__,
721			    ipsec_address(&sav->sah->saidx.src, sbuf,
722				sizeof(sbuf)),
723			    ipsec_address(&sav->sah->saidx.dst, dbuf,
724				sizeof(dbuf)), ntohl(sav->spi), error));
725			goto bad;
726		}
727	}
728
729#ifdef DEV_ENC
730	ipsec_bpf(m, isr->sav, dst->sa.sa_family, ENC_OUT|ENC_AFTER);
731	/* pass the mbuf to enc0 for packet filtering */
732	if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_AFTER)) != 0)
733		goto bad;
734#endif /* DEV_ENC */
735
736	switch(dst->sa.sa_family) {
737#ifdef INET
738	case AF_INET:
739		{
740		struct ip *ip;
741		ip = mtod(m, struct ip *);
742		i = ip->ip_hl << 2;
743		off = offsetof(struct ip, ip_p);
744		}
745		break;
746#endif /* AF_INET */
747	case AF_INET6:
748		i = sizeof(struct ip6_hdr);
749		off = offsetof(struct ip6_hdr, ip6_nxt);
750		break;
751	default:
752		DPRINTF(("%s: unsupported protocol family %u\n",
753				 __func__, dst->sa.sa_family));
754		error = EPFNOSUPPORT;
755		IPSEC6STAT_INC(ips_out_inval);
756		goto bad;
757	}
758	error = (*sav->tdb_xform->xf_output)(m, isr, NULL, i, off);
759	IPSECREQUEST_UNLOCK(isr);
760	return error;
761bad:
762
763	if (isr)
764		IPSECREQUEST_UNLOCK(isr);
765	if (m)
766		m_freem(m);
767	return error;
768}
769#endif /*INET6*/
770