1 /* $OpenBSD: ip6_output.c,v 1.272 2022/11/12 02:50:59 kn Exp $ */
2 /* $KAME: ip6_output.c,v 1.172 2001/03/25 09:55:56 itojun Exp $ */
3
4 /*
5 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of the project nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 */
32
33 /*
34 * Copyright (c) 1982, 1986, 1988, 1990, 1993
35 * The Regents of the University of California. All rights reserved.
36 *
37 * Redistribution and use in source and binary forms, with or without
38 * modification, are permitted provided that the following conditions
39 * are met:
40 * 1. Redistributions of source code must retain the above copyright
41 * notice, this list of conditions and the following disclaimer.
42 * 2. Redistributions in binary form must reproduce the above copyright
43 * notice, this list of conditions and the following disclaimer in the
44 * documentation and/or other materials provided with the distribution.
45 * 3. Neither the name of the University nor the names of its contributors
46 * may be used to endorse or promote products derived from this software
47 * without specific prior written permission.
48 *
49 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
50 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
51 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
52 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
53 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
54 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
55 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
56 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
57 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
58 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
59 * SUCH DAMAGE.
60 *
61 * @(#)ip_output.c 8.3 (Berkeley) 1/21/94
62 */
63
64 #include "pf.h"
65
66 #include <sys/param.h>
67 #include <sys/malloc.h>
68 #include <sys/mbuf.h>
69 #include <sys/errno.h>
70 #include <sys/protosw.h>
71 #include <sys/socket.h>
72 #include <sys/socketvar.h>
73 #include <sys/proc.h>
74 #include <sys/systm.h>
75
76 #include <net/if.h>
77 #include <net/if_var.h>
78 #include <net/if_enc.h>
79 #include <net/route.h>
80
81 #include <netinet/in.h>
82 #include <netinet/ip.h>
83 #include <netinet/in_pcb.h>
84 #include <netinet/udp.h>
85 #include <netinet/tcp.h>
86
87 #include <netinet/ip_var.h>
88 #include <netinet/tcp_timer.h>
89 #include <netinet/tcp_var.h>
90 #include <netinet/udp_var.h>
91
92 #include <netinet6/in6_var.h>
93 #include <netinet/ip6.h>
94 #include <netinet/icmp6.h>
95 #include <netinet6/ip6_var.h>
96 #include <netinet6/nd6.h>
97
98 #include <crypto/idgen.h>
99
100 #if NPF > 0
101 #include <net/pfvar.h>
102 #endif
103
104 #ifdef IPSEC
105 #include <netinet/ip_ipsp.h>
106 #include <netinet/ip_ah.h>
107 #include <netinet/ip_esp.h>
108
109 #ifdef ENCDEBUG
110 #define DPRINTF(fmt, args...) \
111 do { \
112 if (encdebug) \
113 printf("%s: " fmt "\n", __func__, ## args); \
114 } while (0)
115 #else
116 #define DPRINTF(fmt, args...) \
117 do { } while (0)
118 #endif
119 #endif /* IPSEC */
120
121 struct ip6_exthdrs {
122 struct mbuf *ip6e_ip6;
123 struct mbuf *ip6e_hbh;
124 struct mbuf *ip6e_dest1;
125 struct mbuf *ip6e_rthdr;
126 struct mbuf *ip6e_dest2;
127 };
128
129 int ip6_pcbopt(int, u_char *, int, struct ip6_pktopts **, int, int);
130 int ip6_getpcbopt(struct ip6_pktopts *, int, struct mbuf *);
131 int ip6_setpktopt(int, u_char *, int, struct ip6_pktopts *, int, int, int);
132 int ip6_setmoptions(int, struct ip6_moptions **, struct mbuf *, unsigned int);
133 int ip6_getmoptions(int, struct ip6_moptions *, struct mbuf *);
134 int ip6_copyexthdr(struct mbuf **, caddr_t, int);
135 int ip6_insertfraghdr(struct mbuf *, struct mbuf *, int,
136 struct ip6_frag **);
137 int ip6_insert_jumboopt(struct ip6_exthdrs *, u_int32_t);
138 int ip6_splithdr(struct mbuf *, struct ip6_exthdrs *);
139 int ip6_getpmtu(struct rtentry *, struct ifnet *, u_long *);
140 int copypktopts(struct ip6_pktopts *, struct ip6_pktopts *);
141 static __inline u_int16_t __attribute__((__unused__))
142 in6_cksum_phdr(const struct in6_addr *, const struct in6_addr *,
143 u_int32_t, u_int32_t);
144 void in6_delayed_cksum(struct mbuf *, u_int8_t);
145
146 int ip6_output_ipsec_pmtu_update(struct tdb *, struct route_in6 *,
147 struct in6_addr *, int, int, int);
148
149 /* Context for non-repeating IDs */
150 struct idgen32_ctx ip6_id_ctx;
151
152 /*
153 * IP6 output. The packet in mbuf chain m contains a skeletal IP6
154 * header (with pri, len, nxt, hlim, src, dst).
155 * This function may modify ver and hlim only.
156 * The mbuf chain containing the packet will be freed.
157 * The mbuf opt, if present, will not be freed.
158 *
159 * type of "mtu": rt_mtu is u_long, ifnet.ifr_mtu is int.
160 * We use u_long to hold largest one, * which is rt_mtu.
161 */
162 int
163 ip6_output(struct mbuf *m, struct ip6_pktopts *opt, struct route_in6 *ro,
164 int flags, struct ip6_moptions *im6o, struct inpcb *inp)
165 {
166 struct ip6_hdr *ip6;
167 struct ifnet *ifp = NULL;
168 struct mbuf_list fml;
169 int hlen, tlen;
170 struct route_in6 ip6route;
171 struct rtentry *rt = NULL;
172 struct sockaddr_in6 *dst, dstsock;
173 int error = 0;
174 u_long mtu;
175 int dontfrag;
176 u_int16_t src_scope, dst_scope;
177 u_int32_t optlen = 0, plen = 0, unfragpartlen = 0;
178 struct ip6_exthdrs exthdrs;
179 struct in6_addr finaldst;
180 struct route_in6 *ro_pmtu = NULL;
181 int hdrsplit = 0;
182 u_int8_t sproto = 0;
183 u_char nextproto;
184 #ifdef IPSEC
185 struct tdb *tdb = NULL;
186 #endif /* IPSEC */
187
188 #ifdef IPSEC
189 if (inp && (inp->inp_flags & INP_IPV6) == 0)
190 panic("%s: IPv4 pcb is passed", __func__);
191 #endif /* IPSEC */
192
193 ip6 = mtod(m, struct ip6_hdr *);
194 finaldst = ip6->ip6_dst;
195
196 #define MAKE_EXTHDR(hp, mp) \
197 do { \
198 if (hp) { \
199 struct ip6_ext *eh = (struct ip6_ext *)(hp); \
200 error = ip6_copyexthdr((mp), (caddr_t)(hp), \
201 ((eh)->ip6e_len + 1) << 3); \
202 if (error) \
203 goto freehdrs; \
204 } \
205 } while (0)
206
207 bzero(&exthdrs, sizeof(exthdrs));
208
209 if (opt) {
210 /* Hop-by-Hop options header */
211 MAKE_EXTHDR(opt->ip6po_hbh, &exthdrs.ip6e_hbh);
212 /* Destination options header(1st part) */
213 MAKE_EXTHDR(opt->ip6po_dest1, &exthdrs.ip6e_dest1);
214 /* Routing header */
215 MAKE_EXTHDR(opt->ip6po_rthdr, &exthdrs.ip6e_rthdr);
216 /* Destination options header(2nd part) */
217 MAKE_EXTHDR(opt->ip6po_dest2, &exthdrs.ip6e_dest2);
218 }
219
220 #ifdef IPSEC
221 if (ipsec_in_use || inp != NULL) {
222 error = ip6_output_ipsec_lookup(m, inp, &tdb);
223 if (error) {
224 /*
225 * -EINVAL is used to indicate that the packet should
226 * be silently dropped, typically because we've asked
227 * key management for an SA.
228 */
229 if (error == -EINVAL) /* Should silently drop packet */
230 error = 0;
231
232 goto freehdrs;
233 }
234 }
235 #endif /* IPSEC */
236
237 /*
238 * Calculate the total length of the extension header chain.
239 * Keep the length of the unfragmentable part for fragmentation.
240 */
241 optlen = 0;
242 if (exthdrs.ip6e_hbh) optlen += exthdrs.ip6e_hbh->m_len;
243 if (exthdrs.ip6e_dest1) optlen += exthdrs.ip6e_dest1->m_len;
244 if (exthdrs.ip6e_rthdr) optlen += exthdrs.ip6e_rthdr->m_len;
245 unfragpartlen = optlen + sizeof(struct ip6_hdr);
246 /* NOTE: we don't add AH/ESP length here. do that later. */
247 if (exthdrs.ip6e_dest2) optlen += exthdrs.ip6e_dest2->m_len;
248
249 /*
250 * If we need IPsec, or there is at least one extension header,
251 * separate IP6 header from the payload.
252 */
253 if ((sproto || optlen) && !hdrsplit) {
254 if ((error = ip6_splithdr(m, &exthdrs)) != 0) {
255 m = NULL;
256 goto freehdrs;
257 }
258 m = exthdrs.ip6e_ip6;
259 hdrsplit++;
260 }
261
262 /* adjust pointer */
263 ip6 = mtod(m, struct ip6_hdr *);
264
265 /* adjust mbuf packet header length */
266 m->m_pkthdr.len += optlen;
267 plen = m->m_pkthdr.len - sizeof(*ip6);
268
269 /* If this is a jumbo payload, insert a jumbo payload option. */
270 if (plen > IPV6_MAXPACKET) {
271 if (!hdrsplit) {
272 if ((error = ip6_splithdr(m, &exthdrs)) != 0) {
273 m = NULL;
274 goto freehdrs;
275 }
276 m = exthdrs.ip6e_ip6;
277 hdrsplit++;
278 }
279 /* adjust pointer */
280 ip6 = mtod(m, struct ip6_hdr *);
281 if ((error = ip6_insert_jumboopt(&exthdrs, plen)) != 0)
282 goto freehdrs;
283 ip6->ip6_plen = 0;
284 } else
285 ip6->ip6_plen = htons(plen);
286
287 /*
288 * Concatenate headers and fill in next header fields.
289 * Here we have, on "m"
290 * IPv6 payload
291 * and we insert headers accordingly. Finally, we should be getting:
292 * IPv6 hbh dest1 rthdr ah* [esp* dest2 payload]
293 *
294 * during the header composing process, "m" points to IPv6 header.
295 * "mprev" points to an extension header prior to esp.
296 */
297 {
298 u_char *nexthdrp = &ip6->ip6_nxt;
299 struct mbuf *mprev = m;
300
301 /*
302 * we treat dest2 specially. this makes IPsec processing
303 * much easier. the goal here is to make mprev point the
304 * mbuf prior to dest2.
305 *
306 * result: IPv6 dest2 payload
307 * m and mprev will point to IPv6 header.
308 */
309 if (exthdrs.ip6e_dest2) {
310 if (!hdrsplit)
311 panic("%s: assumption failed: hdr not split",
312 __func__);
313 exthdrs.ip6e_dest2->m_next = m->m_next;
314 m->m_next = exthdrs.ip6e_dest2;
315 *mtod(exthdrs.ip6e_dest2, u_char *) = ip6->ip6_nxt;
316 ip6->ip6_nxt = IPPROTO_DSTOPTS;
317 }
318
319 #define MAKE_CHAIN(m, mp, p, i)\
320 do {\
321 if (m) {\
322 if (!hdrsplit) \
323 panic("assumption failed: hdr not split"); \
324 *mtod((m), u_char *) = *(p);\
325 *(p) = (i);\
326 p = mtod((m), u_char *);\
327 (m)->m_next = (mp)->m_next;\
328 (mp)->m_next = (m);\
329 (mp) = (m);\
330 }\
331 } while (0)
332 /*
333 * result: IPv6 hbh dest1 rthdr dest2 payload
334 * m will point to IPv6 header. mprev will point to the
335 * extension header prior to dest2 (rthdr in the above case).
336 */
337 MAKE_CHAIN(exthdrs.ip6e_hbh, mprev, nexthdrp, IPPROTO_HOPOPTS);
338 MAKE_CHAIN(exthdrs.ip6e_dest1, mprev, nexthdrp,
339 IPPROTO_DSTOPTS);
340 MAKE_CHAIN(exthdrs.ip6e_rthdr, mprev, nexthdrp,
341 IPPROTO_ROUTING);
342 }
343
344 /*
345 * If there is a routing header, replace the destination address field
346 * with the first hop of the routing header.
347 */
348 if (exthdrs.ip6e_rthdr) {
349 struct ip6_rthdr *rh;
350 struct ip6_rthdr0 *rh0;
351 struct in6_addr *addr;
352
353 rh = (struct ip6_rthdr *)(mtod(exthdrs.ip6e_rthdr,
354 struct ip6_rthdr *));
355 switch (rh->ip6r_type) {
356 case IPV6_RTHDR_TYPE_0:
357 rh0 = (struct ip6_rthdr0 *)rh;
358 addr = (struct in6_addr *)(rh0 + 1);
359 ip6->ip6_dst = addr[0];
360 bcopy(&addr[1], &addr[0],
361 sizeof(struct in6_addr) * (rh0->ip6r0_segleft - 1));
362 addr[rh0->ip6r0_segleft - 1] = finaldst;
363 break;
364 default: /* is it possible? */
365 error = EINVAL;
366 goto bad;
367 }
368 }
369
370 /* Source address validation */
371 if (!(flags & IPV6_UNSPECSRC) &&
372 IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src)) {
373 /*
374 * XXX: we can probably assume validation in the caller, but
375 * we explicitly check the address here for safety.
376 */
377 error = EOPNOTSUPP;
378 ip6stat_inc(ip6s_badscope);
379 goto bad;
380 }
381 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src)) {
382 error = EOPNOTSUPP;
383 ip6stat_inc(ip6s_badscope);
384 goto bad;
385 }
386
387 ip6stat_inc(ip6s_localout);
388
389 /*
390 * Route packet.
391 */
392 #if NPF > 0
393 reroute:
394 #endif
395
396 /* initialize cached route */
397 if (ro == NULL) {
398 ro = &ip6route;
399 bzero((caddr_t)ro, sizeof(*ro));
400 }
401 ro_pmtu = ro;
402 if (opt && opt->ip6po_rthdr)
403 ro = &opt->ip6po_route;
404 dst = &ro->ro_dst;
405
406 /*
407 * if specified, try to fill in the traffic class field.
408 * do not override if a non-zero value is already set.
409 * we check the diffserv field and the ecn field separately.
410 */
411 if (opt && opt->ip6po_tclass >= 0) {
412 int mask = 0;
413
414 if ((ip6->ip6_flow & htonl(0xfc << 20)) == 0)
415 mask |= 0xfc;
416 if ((ip6->ip6_flow & htonl(0x03 << 20)) == 0)
417 mask |= 0x03;
418 if (mask != 0)
419 ip6->ip6_flow |=
420 htonl((opt->ip6po_tclass & mask) << 20);
421 }
422
423 /* fill in or override the hop limit field, if necessary. */
424 if (opt && opt->ip6po_hlim != -1)
425 ip6->ip6_hlim = opt->ip6po_hlim & 0xff;
426 else if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
427 if (im6o != NULL)
428 ip6->ip6_hlim = im6o->im6o_hlim;
429 else
430 ip6->ip6_hlim = ip6_defmcasthlim;
431 }
432
433 #ifdef IPSEC
434 if (tdb != NULL) {
435 /*
436 * XXX what should we do if ip6_hlim == 0 and the
437 * packet gets tunneled?
438 */
439 /*
440 * if we are source-routing, do not attempt to tunnel the
441 * packet just because ip6_dst is different from what tdb has.
442 * XXX
443 */
444 error = ip6_output_ipsec_send(tdb, m, ro,
445 exthdrs.ip6e_rthdr ? 1 : 0, 0);
446 goto done;
447 }
448 #endif /* IPSEC */
449
450 bzero(&dstsock, sizeof(dstsock));
451 dstsock.sin6_family = AF_INET6;
452 dstsock.sin6_addr = ip6->ip6_dst;
453 dstsock.sin6_len = sizeof(dstsock);
454 ro->ro_tableid = m->m_pkthdr.ph_rtableid;
455
456 if (IN6_IS_ADDR_MULTICAST(&dstsock.sin6_addr)) {
457 struct in6_pktinfo *pi = NULL;
458
459 /*
460 * If the caller specify the outgoing interface
461 * explicitly, use it.
462 */
463 if (opt != NULL && (pi = opt->ip6po_pktinfo) != NULL)
464 ifp = if_get(pi->ipi6_ifindex);
465
466 if (ifp == NULL && im6o != NULL)
467 ifp = if_get(im6o->im6o_ifidx);
468 }
469
470 if (ifp == NULL) {
471 rt = in6_selectroute(&dstsock, opt, ro, ro->ro_tableid);
472 if (rt == NULL) {
473 ip6stat_inc(ip6s_noroute);
474 error = EHOSTUNREACH;
475 goto bad;
476 }
477 if (ISSET(rt->rt_flags, RTF_LOCAL))
478 ifp = if_get(rtable_loindex(m->m_pkthdr.ph_rtableid));
479 else
480 ifp = if_get(rt->rt_ifidx);
481 /*
482 * We aren't using rtisvalid() here because the UP/DOWN state
483 * machine is broken with some Ethernet drivers like em(4).
484 * As a result we might try to use an invalid cached route
485 * entry while an interface is being detached.
486 */
487 if (ifp == NULL) {
488 ip6stat_inc(ip6s_noroute);
489 error = EHOSTUNREACH;
490 goto bad;
491 }
492 } else {
493 *dst = dstsock;
494 }
495
496 if (rt && (rt->rt_flags & RTF_GATEWAY) &&
497 !IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst))
498 dst = satosin6(rt->rt_gateway);
499
500 if (!IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
501 /* Unicast */
502
503 m->m_flags &= ~(M_BCAST | M_MCAST); /* just in case */
504 } else {
505 /* Multicast */
506
507 m->m_flags = (m->m_flags & ~M_BCAST) | M_MCAST;
508
509 /*
510 * Confirm that the outgoing interface supports multicast.
511 */
512 if ((ifp->if_flags & IFF_MULTICAST) == 0) {
513 ip6stat_inc(ip6s_noroute);
514 error = ENETUNREACH;
515 goto bad;
516 }
517
518 if ((im6o == NULL || im6o->im6o_loop) &&
519 in6_hasmulti(&ip6->ip6_dst, ifp)) {
520 /*
521 * If we belong to the destination multicast group
522 * on the outgoing interface, and the caller did not
523 * forbid loopback, loop back a copy.
524 * Can't defer TCP/UDP checksumming, do the
525 * computation now.
526 */
527 in6_proto_cksum_out(m, NULL);
528 ip6_mloopback(ifp, m, dst);
529 }
530 #ifdef MROUTING
531 else {
532 /*
533 * If we are acting as a multicast router, perform
534 * multicast forwarding as if the packet had just
535 * arrived on the interface to which we are about
536 * to send. The multicast forwarding function
537 * recursively calls this function, using the
538 * IPV6_FORWARDING flag to prevent infinite recursion.
539 *
540 * Multicasts that are looped back by ip6_mloopback(),
541 * above, will be forwarded by the ip6_input() routine,
542 * if necessary.
543 */
544 if (ip6_mforwarding && ip6_mrouter[ifp->if_rdomain] &&
545 (flags & IPV6_FORWARDING) == 0) {
546 if (ip6_mforward(ip6, ifp, m) != 0) {
547 m_freem(m);
548 goto done;
549 }
550 }
551 }
552 #endif
553 /*
554 * Multicasts with a hoplimit of zero may be looped back,
555 * above, but must not be transmitted on a network.
556 * Also, multicasts addressed to the loopback interface
557 * are not sent -- the above call to ip6_mloopback() will
558 * loop back a copy if this host actually belongs to the
559 * destination group on the loopback interface.
560 */
561 if (ip6->ip6_hlim == 0 || (ifp->if_flags & IFF_LOOPBACK) ||
562 IN6_IS_ADDR_MC_INTFACELOCAL(&ip6->ip6_dst)) {
563 m_freem(m);
564 goto done;
565 }
566 }
567
568 /*
569 * If this packet is going through a loopback interface we won't
570 * be able to restore its scope ID using the interface index.
571 */
572 if (IN6_IS_SCOPE_EMBED(&ip6->ip6_src)) {
573 if (ifp->if_flags & IFF_LOOPBACK)
574 src_scope = ip6->ip6_src.s6_addr16[1];
575 ip6->ip6_src.s6_addr16[1] = 0;
576 }
577 if (IN6_IS_SCOPE_EMBED(&ip6->ip6_dst)) {
578 if (ifp->if_flags & IFF_LOOPBACK)
579 dst_scope = ip6->ip6_dst.s6_addr16[1];
580 ip6->ip6_dst.s6_addr16[1] = 0;
581 }
582
583 /* Determine path MTU. */
584 if ((error = ip6_getpmtu(ro_pmtu->ro_rt, ifp, &mtu)) != 0)
585 goto bad;
586
587 /*
588 * The caller of this function may specify to use the minimum MTU
589 * in some cases.
590 * An advanced API option (IPV6_USE_MIN_MTU) can also override MTU
591 * setting. The logic is a bit complicated; by default, unicast
592 * packets will follow path MTU while multicast packets will be sent at
593 * the minimum MTU. If IP6PO_MINMTU_ALL is specified, all packets
594 * including unicast ones will be sent at the minimum MTU. Multicast
595 * packets will always be sent at the minimum MTU unless
596 * IP6PO_MINMTU_DISABLE is explicitly specified.
597 * See RFC 3542 for more details.
598 */
599 if (mtu > IPV6_MMTU) {
600 if ((flags & IPV6_MINMTU))
601 mtu = IPV6_MMTU;
602 else if (opt && opt->ip6po_minmtu == IP6PO_MINMTU_ALL)
603 mtu = IPV6_MMTU;
604 else if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) && (opt == NULL ||
605 opt->ip6po_minmtu != IP6PO_MINMTU_DISABLE)) {
606 mtu = IPV6_MMTU;
607 }
608 }
609
610 /*
611 * If the outgoing packet contains a hop-by-hop options header,
612 * it must be examined and processed even by the source node.
613 * (RFC 2460, section 4.)
614 */
615 if (exthdrs.ip6e_hbh) {
616 struct ip6_hbh *hbh = mtod(exthdrs.ip6e_hbh, struct ip6_hbh *);
617 u_int32_t rtalert; /* returned value is ignored */
618 u_int32_t plen = 0; /* no more than 1 jumbo payload option! */
619
620 m->m_pkthdr.ph_ifidx = ifp->if_index;
621 if (ip6_process_hopopts(&m, (u_int8_t *)(hbh + 1),
622 ((hbh->ip6h_len + 1) << 3) - sizeof(struct ip6_hbh),
623 &rtalert, &plen) < 0) {
624 /* m was already freed at this point */
625 error = EINVAL;/* better error? */
626 goto done;
627 }
628 m->m_pkthdr.ph_ifidx = 0;
629 }
630
631 #if NPF > 0
632 if (pf_test(AF_INET6, PF_OUT, ifp, &m) != PF_PASS) {
633 error = EACCES;
634 m_freem(m);
635 goto done;
636 }
637 if (m == NULL)
638 goto done;
639 ip6 = mtod(m, struct ip6_hdr *);
640 if ((m->m_pkthdr.pf.flags & (PF_TAG_REROUTE | PF_TAG_GENERATED)) ==
641 (PF_TAG_REROUTE | PF_TAG_GENERATED)) {
642 /* already rerun the route lookup, go on */
643 m->m_pkthdr.pf.flags &= ~(PF_TAG_GENERATED | PF_TAG_REROUTE);
644 } else if (m->m_pkthdr.pf.flags & PF_TAG_REROUTE) {
645 /* tag as generated to skip over pf_test on rerun */
646 m->m_pkthdr.pf.flags |= PF_TAG_GENERATED;
647 finaldst = ip6->ip6_dst;
648 ro = NULL;
649 if_put(ifp); /* drop reference since destination changed */
650 ifp = NULL;
651 goto reroute;
652 }
653 #endif
654
655 /*
656 * If the packet is not going on the wire it can be destined
657 * to any local address. In this case do not clear its scopes
658 * to let ip6_input() find a matching local route.
659 */
660 if (ifp->if_flags & IFF_LOOPBACK) {
661 if (IN6_IS_SCOPE_EMBED(&ip6->ip6_src))
662 ip6->ip6_src.s6_addr16[1] = src_scope;
663 if (IN6_IS_SCOPE_EMBED(&ip6->ip6_dst))
664 ip6->ip6_dst.s6_addr16[1] = dst_scope;
665 }
666
667 in6_proto_cksum_out(m, ifp);
668
669 /*
670 * Send the packet to the outgoing interface.
671 * If necessary, do IPv6 fragmentation before sending.
672 *
673 * the logic here is rather complex:
674 * 1: normal case (dontfrag == 0)
675 * 1-a: send as is if tlen <= path mtu
676 * 1-b: fragment if tlen > path mtu
677 *
678 * 2: if user asks us not to fragment (dontfrag == 1)
679 * 2-a: send as is if tlen <= interface mtu
680 * 2-b: error if tlen > interface mtu
681 */
682 tlen = m->m_pkthdr.len;
683
684 if (ISSET(m->m_pkthdr.csum_flags, M_IPV6_DF_OUT)) {
685 CLR(m->m_pkthdr.csum_flags, M_IPV6_DF_OUT);
686 dontfrag = 1;
687 } else if (opt && ISSET(opt->ip6po_flags, IP6PO_DONTFRAG))
688 dontfrag = 1;
689 else
690 dontfrag = 0;
691 if (dontfrag && tlen > ifp->if_mtu) { /* case 2-b */
692 #ifdef IPSEC
693 if (ip_mtudisc)
694 ipsec_adjust_mtu(m, mtu);
695 #endif
696 error = EMSGSIZE;
697 goto bad;
698 }
699
700 /*
701 * transmit packet without fragmentation
702 */
703 if (dontfrag || (tlen <= mtu)) { /* case 1-a and 2-a */
704 error = ifp->if_output(ifp, m, sin6tosa(dst), ro->ro_rt);
705 goto done;
706 }
707
708 /*
709 * try to fragment the packet. case 1-b
710 */
711 if (mtu < IPV6_MMTU) {
712 /* path MTU cannot be less than IPV6_MMTU */
713 error = EMSGSIZE;
714 goto bad;
715 } else if (ip6->ip6_plen == 0) {
716 /* jumbo payload cannot be fragmented */
717 error = EMSGSIZE;
718 goto bad;
719 }
720
721 /*
722 * Too large for the destination or interface;
723 * fragment if possible.
724 * Must be able to put at least 8 bytes per fragment.
725 */
726 hlen = unfragpartlen;
727 if (mtu > IPV6_MAXPACKET)
728 mtu = IPV6_MAXPACKET;
729
730 /*
731 * If we are doing fragmentation, we can't defer TCP/UDP
732 * checksumming; compute the checksum and clear the flag.
733 */
734 in6_proto_cksum_out(m, NULL);
735
736 /*
737 * Change the next header field of the last header in the
738 * unfragmentable part.
739 */
740 if (exthdrs.ip6e_rthdr) {
741 nextproto = *mtod(exthdrs.ip6e_rthdr, u_char *);
742 *mtod(exthdrs.ip6e_rthdr, u_char *) = IPPROTO_FRAGMENT;
743 } else if (exthdrs.ip6e_dest1) {
744 nextproto = *mtod(exthdrs.ip6e_dest1, u_char *);
745 *mtod(exthdrs.ip6e_dest1, u_char *) = IPPROTO_FRAGMENT;
746 } else if (exthdrs.ip6e_hbh) {
747 nextproto = *mtod(exthdrs.ip6e_hbh, u_char *);
748 *mtod(exthdrs.ip6e_hbh, u_char *) = IPPROTO_FRAGMENT;
749 } else {
750 nextproto = ip6->ip6_nxt;
751 ip6->ip6_nxt = IPPROTO_FRAGMENT;
752 }
753
754 error = ip6_fragment(m, &fml, hlen, nextproto, mtu);
755 if (error)
756 goto done;
757
758 while ((m = ml_dequeue(&fml)) != NULL) {
759 error = ifp->if_output(ifp, m, sin6tosa(dst), ro->ro_rt);
760 if (error)
761 break;
762 }
763 if (error)
764 ml_purge(&fml);
765 else
766 ip6stat_inc(ip6s_fragmented);
767
768 done:
769 if (ro == &ip6route && ro->ro_rt) {
770 rtfree(ro->ro_rt);
771 } else if (ro_pmtu == &ip6route && ro_pmtu->ro_rt) {
772 rtfree(ro_pmtu->ro_rt);
773 }
774 if_put(ifp);
775 #ifdef IPSEC
776 tdb_unref(tdb);
777 #endif /* IPSEC */
778 return (error);
779
780 freehdrs:
781 m_freem(exthdrs.ip6e_hbh); /* m_freem will check if mbuf is 0 */
782 m_freem(exthdrs.ip6e_dest1);
783 m_freem(exthdrs.ip6e_rthdr);
784 m_freem(exthdrs.ip6e_dest2);
785 /* FALLTHROUGH */
786 bad:
787 m_freem(m);
788 goto done;
789 }
790
791 int
792 ip6_fragment(struct mbuf *m0, struct mbuf_list *fml, int hlen,
793 u_char nextproto, u_long mtu)
794 {
795 struct mbuf *m;
796 struct ip6_hdr *ip6;
797 u_int32_t id;
798 int tlen, len, off;
799 int error;
800
801 ml_init(fml);
802
803 ip6 = mtod(m0, struct ip6_hdr *);
804 tlen = m0->m_pkthdr.len;
805 len = (mtu - hlen - sizeof(struct ip6_frag)) & ~7;
806 if (len < 8) {
807 error = EMSGSIZE;
808 goto bad;
809 }
810 id = htonl(ip6_randomid());
811
812 /*
813 * Loop through length of segment,
814 * make new header and copy data of each part and link onto chain.
815 */
816 for (off = hlen; off < tlen; off += len) {
817 struct mbuf *mlast;
818 struct ip6_hdr *mhip6;
819 struct ip6_frag *ip6f;
820
821 MGETHDR(m, M_DONTWAIT, MT_HEADER);
822 if (m == NULL) {
823 error = ENOBUFS;
824 goto bad;
825 }
826 ml_enqueue(fml, m);
827
828 if ((error = m_dup_pkthdr(m, m0, M_DONTWAIT)) != 0)
829 goto bad;
830 m->m_data += max_linkhdr;
831 mhip6 = mtod(m, struct ip6_hdr *);
832 *mhip6 = *ip6;
833 m->m_len = sizeof(struct ip6_hdr);
834
835 if ((error = ip6_insertfraghdr(m0, m, hlen, &ip6f)) != 0)
836 goto bad;
837 ip6f->ip6f_offlg = htons((off - hlen) & ~7);
838 if (off + len >= tlen)
839 len = tlen - off;
840 else
841 ip6f->ip6f_offlg |= IP6F_MORE_FRAG;
842
843 m->m_pkthdr.len = hlen + sizeof(struct ip6_frag) + len;
844 mhip6->ip6_plen = htons(m->m_pkthdr.len -
845 sizeof(struct ip6_hdr));
846 for (mlast = m; mlast->m_next; mlast = mlast->m_next)
847 ;
848 mlast->m_next = m_copym(m0, off, len, M_DONTWAIT);
849 if (mlast->m_next == NULL) {
850 error = ENOBUFS;
851 goto bad;
852 }
853
854 ip6f->ip6f_reserved = 0;
855 ip6f->ip6f_ident = id;
856 ip6f->ip6f_nxt = nextproto;
857 }
858
859 ip6stat_add(ip6s_ofragments, ml_len(fml));
860 m_freem(m0);
861 return (0);
862
863 bad:
864 ip6stat_inc(ip6s_odropped);
865 ml_purge(fml);
866 m_freem(m0);
867 return (error);
868 }
869
870 int
871 ip6_copyexthdr(struct mbuf **mp, caddr_t hdr, int hlen)
872 {
873 struct mbuf *m;
874
875 if (hlen > MCLBYTES)
876 return (ENOBUFS); /* XXX */
877
878 MGET(m, M_DONTWAIT, MT_DATA);
879 if (!m)
880 return (ENOBUFS);
881
882 if (hlen > MLEN) {
883 MCLGET(m, M_DONTWAIT);
884 if ((m->m_flags & M_EXT) == 0) {
885 m_free(m);
886 return (ENOBUFS);
887 }
888 }
889 m->m_len = hlen;
890 if (hdr)
891 memcpy(mtod(m, caddr_t), hdr, hlen);
892
893 *mp = m;
894 return (0);
895 }
896
897 /*
898 * Insert jumbo payload option.
899 */
900 int
901 ip6_insert_jumboopt(struct ip6_exthdrs *exthdrs, u_int32_t plen)
902 {
903 struct mbuf *mopt;
904 u_int8_t *optbuf;
905 u_int32_t v;
906
907 #define JUMBOOPTLEN 8 /* length of jumbo payload option and padding */
908
909 /*
910 * If there is no hop-by-hop options header, allocate new one.
911 * If there is one but it doesn't have enough space to store the
912 * jumbo payload option, allocate a cluster to store the whole options.
913 * Otherwise, use it to store the options.
914 */
915 if (exthdrs->ip6e_hbh == 0) {
916 MGET(mopt, M_DONTWAIT, MT_DATA);
917 if (mopt == NULL)
918 return (ENOBUFS);
919 mopt->m_len = JUMBOOPTLEN;
920 optbuf = mtod(mopt, u_int8_t *);
921 optbuf[1] = 0; /* = ((JUMBOOPTLEN) >> 3) - 1 */
922 exthdrs->ip6e_hbh = mopt;
923 } else {
924 struct ip6_hbh *hbh;
925
926 mopt = exthdrs->ip6e_hbh;
927 if (m_trailingspace(mopt) < JUMBOOPTLEN) {
928 /*
929 * XXX assumption:
930 * - exthdrs->ip6e_hbh is not referenced from places
931 * other than exthdrs.
932 * - exthdrs->ip6e_hbh is not an mbuf chain.
933 */
934 int oldoptlen = mopt->m_len;
935 struct mbuf *n;
936
937 /*
938 * XXX: give up if the whole (new) hbh header does
939 * not fit even in an mbuf cluster.
940 */
941 if (oldoptlen + JUMBOOPTLEN > MCLBYTES)
942 return (ENOBUFS);
943
944 /*
945 * As a consequence, we must always prepare a cluster
946 * at this point.
947 */
948 MGET(n, M_DONTWAIT, MT_DATA);
949 if (n) {
950 MCLGET(n, M_DONTWAIT);
951 if ((n->m_flags & M_EXT) == 0) {
952 m_freem(n);
953 n = NULL;
954 }
955 }
956 if (!n)
957 return (ENOBUFS);
958 n->m_len = oldoptlen + JUMBOOPTLEN;
959 memcpy(mtod(n, caddr_t), mtod(mopt, caddr_t),
960 oldoptlen);
961 optbuf = mtod(n, u_int8_t *) + oldoptlen;
962 m_freem(mopt);
963 mopt = exthdrs->ip6e_hbh = n;
964 } else {
965 optbuf = mtod(mopt, u_int8_t *) + mopt->m_len;
966 mopt->m_len += JUMBOOPTLEN;
967 }
968 optbuf[0] = IP6OPT_PADN;
969 optbuf[1] = 0;
970
971 /*
972 * Adjust the header length according to the pad and
973 * the jumbo payload option.
974 */
975 hbh = mtod(mopt, struct ip6_hbh *);
976 hbh->ip6h_len += (JUMBOOPTLEN >> 3);
977 }
978
979 /* fill in the option. */
980 optbuf[2] = IP6OPT_JUMBO;
981 optbuf[3] = 4;
982 v = (u_int32_t)htonl(plen + JUMBOOPTLEN);
983 memcpy(&optbuf[4], &v, sizeof(u_int32_t));
984
985 /* finally, adjust the packet header length */
986 exthdrs->ip6e_ip6->m_pkthdr.len += JUMBOOPTLEN;
987
988 return (0);
989 #undef JUMBOOPTLEN
990 }
991
992 /*
993 * Insert fragment header and copy unfragmentable header portions.
994 */
995 int
996 ip6_insertfraghdr(struct mbuf *m0, struct mbuf *m, int hlen,
997 struct ip6_frag **frghdrp)
998 {
999 struct mbuf *n, *mlast;
1000
1001 if (hlen > sizeof(struct ip6_hdr)) {
1002 n = m_copym(m0, sizeof(struct ip6_hdr),
1003 hlen - sizeof(struct ip6_hdr), M_DONTWAIT);
1004 if (n == NULL)
1005 return (ENOBUFS);
1006 m->m_next = n;
1007 } else
1008 n = m;
1009
1010 /* Search for the last mbuf of unfragmentable part. */
1011 for (mlast = n; mlast->m_next; mlast = mlast->m_next)
1012 ;
1013
1014 if ((mlast->m_flags & M_EXT) == 0 &&
1015 m_trailingspace(mlast) >= sizeof(struct ip6_frag)) {
1016 /* use the trailing space of the last mbuf for fragment hdr */
1017 *frghdrp = (struct ip6_frag *)(mtod(mlast, caddr_t) +
1018 mlast->m_len);
1019 mlast->m_len += sizeof(struct ip6_frag);
1020 m->m_pkthdr.len += sizeof(struct ip6_frag);
1021 } else {
1022 /* allocate a new mbuf for the fragment header */
1023 struct mbuf *mfrg;
1024
1025 MGET(mfrg, M_DONTWAIT, MT_DATA);
1026 if (mfrg == NULL)
1027 return (ENOBUFS);
1028 mfrg->m_len = sizeof(struct ip6_frag);
1029 *frghdrp = mtod(mfrg, struct ip6_frag *);
1030 mlast->m_next = mfrg;
1031 }
1032
1033 return (0);
1034 }
1035
1036 int
1037 ip6_getpmtu(struct rtentry *rt, struct ifnet *ifp, u_long *mtup)
1038 {
1039 u_int32_t mtu = 0;
1040 int error = 0;
1041
1042 if (rt != NULL) {
1043 mtu = rt->rt_mtu;
1044 if (mtu == 0)
1045 mtu = ifp->if_mtu;
1046 else if (mtu < IPV6_MMTU) {
1047 /* RFC8021 IPv6 Atomic Fragments Considered Harmful */
1048 mtu = IPV6_MMTU;
1049 } else if (mtu > ifp->if_mtu) {
1050 /*
1051 * The MTU on the route is larger than the MTU on
1052 * the interface! This shouldn't happen, unless the
1053 * MTU of the interface has been changed after the
1054 * interface was brought up. Change the MTU in the
1055 * route to match the interface MTU (as long as the
1056 * field isn't locked).
1057 */
1058 mtu = ifp->if_mtu;
1059 if (!(rt->rt_locks & RTV_MTU))
1060 rt->rt_mtu = mtu;
1061 }
1062 } else {
1063 mtu = ifp->if_mtu;
1064 }
1065
1066 *mtup = mtu;
1067 return (error);
1068 }
1069
1070 /*
1071 * IP6 socket option processing.
1072 */
1073 int
1074 ip6_ctloutput(int op, struct socket *so, int level, int optname,
1075 struct mbuf *m)
1076 {
1077 int privileged, optdatalen, uproto;
1078 void *optdata;
1079 struct inpcb *inp = sotoinpcb(so);
1080 int error, optval;
1081 struct proc *p = curproc; /* For IPsec and rdomain */
1082 u_int rtableid, rtid = 0;
1083
1084 error = optval = 0;
1085
1086 privileged = (inp->inp_socket->so_state & SS_PRIV);
1087 uproto = (int)so->so_proto->pr_protocol;
1088
1089 if (level != IPPROTO_IPV6)
1090 return (EINVAL);
1091
1092 rtableid = p->p_p->ps_rtableid;
1093
1094 switch (op) {
1095 case PRCO_SETOPT:
1096 switch (optname) {
1097 /*
1098 * Use of some Hop-by-Hop options or some
1099 * Destination options, might require special
1100 * privilege. That is, normal applications
1101 * (without special privilege) might be forbidden
1102 * from setting certain options in outgoing packets,
1103 * and might never see certain options in received
1104 * packets. [RFC 2292 Section 6]
1105 * KAME specific note:
1106 * KAME prevents non-privileged users from sending or
1107 * receiving ANY hbh/dst options in order to avoid
1108 * overhead of parsing options in the kernel.
1109 */
1110 case IPV6_RECVHOPOPTS:
1111 case IPV6_RECVDSTOPTS:
1112 if (!privileged) {
1113 error = EPERM;
1114 break;
1115 }
1116 /* FALLTHROUGH */
1117 case IPV6_UNICAST_HOPS:
1118 case IPV6_MINHOPCOUNT:
1119 case IPV6_HOPLIMIT:
1120
1121 case IPV6_RECVPKTINFO:
1122 case IPV6_RECVHOPLIMIT:
1123 case IPV6_RECVRTHDR:
1124 case IPV6_RECVPATHMTU:
1125 case IPV6_RECVTCLASS:
1126 case IPV6_V6ONLY:
1127 case IPV6_AUTOFLOWLABEL:
1128 case IPV6_RECVDSTPORT:
1129 if (m == NULL || m->m_len != sizeof(int)) {
1130 error = EINVAL;
1131 break;
1132 }
1133 optval = *mtod(m, int *);
1134 switch (optname) {
1135
1136 case IPV6_UNICAST_HOPS:
1137 if (optval < -1 || optval >= 256)
1138 error = EINVAL;
1139 else {
1140 /* -1 = kernel default */
1141 inp->inp_hops = optval;
1142 }
1143 break;
1144
1145 case IPV6_MINHOPCOUNT:
1146 if (optval < 0 || optval > 255)
1147 error = EINVAL;
1148 else
1149 inp->inp_ip6_minhlim = optval;
1150 break;
1151
1152 #define OPTSET(bit) \
1153 do { \
1154 if (optval) \
1155 inp->inp_flags |= (bit); \
1156 else \
1157 inp->inp_flags &= ~(bit); \
1158 } while (/*CONSTCOND*/ 0)
1159 #define OPTBIT(bit) (inp->inp_flags & (bit) ? 1 : 0)
1160
1161 case IPV6_RECVPKTINFO:
1162 OPTSET(IN6P_PKTINFO);
1163 break;
1164
1165 case IPV6_HOPLIMIT:
1166 {
1167 struct ip6_pktopts **optp;
1168
1169 optp = &inp->inp_outputopts6;
1170 error = ip6_pcbopt(IPV6_HOPLIMIT,
1171 (u_char *)&optval, sizeof(optval), optp,
1172 privileged, uproto);
1173 break;
1174 }
1175
1176 case IPV6_RECVHOPLIMIT:
1177 OPTSET(IN6P_HOPLIMIT);
1178 break;
1179
1180 case IPV6_RECVHOPOPTS:
1181 OPTSET(IN6P_HOPOPTS);
1182 break;
1183
1184 case IPV6_RECVDSTOPTS:
1185 OPTSET(IN6P_DSTOPTS);
1186 break;
1187
1188 case IPV6_RECVRTHDR:
1189 OPTSET(IN6P_RTHDR);
1190 break;
1191
1192 case IPV6_RECVPATHMTU:
1193 /*
1194 * We ignore this option for TCP
1195 * sockets.
1196 * (RFC3542 leaves this case
1197 * unspecified.)
1198 */
1199 if (uproto != IPPROTO_TCP)
1200 OPTSET(IN6P_MTU);
1201 break;
1202
1203 case IPV6_V6ONLY:
1204 /*
1205 * make setsockopt(IPV6_V6ONLY)
1206 * available only prior to bind(2).
1207 * see ipng mailing list, Jun 22 2001.
1208 */
1209 if (inp->inp_lport || !IN6_IS_ADDR_UNSPECIFIED(
1210 &inp->inp_laddr6)) {
1211 error = EINVAL;
1212 break;
1213 }
1214 /* No support for IPv4-mapped addresses. */
1215 if (!optval)
1216 error = EINVAL;
1217 else
1218 error = 0;
1219 break;
1220 case IPV6_RECVTCLASS:
1221 OPTSET(IN6P_TCLASS);
1222 break;
1223 case IPV6_AUTOFLOWLABEL:
1224 OPTSET(IN6P_AUTOFLOWLABEL);
1225 break;
1226
1227 case IPV6_RECVDSTPORT:
1228 OPTSET(IN6P_RECVDSTPORT);
1229 break;
1230 }
1231 break;
1232
1233 case IPV6_TCLASS:
1234 case IPV6_DONTFRAG:
1235 case IPV6_USE_MIN_MTU:
1236 if (m == NULL || m->m_len != sizeof(optval)) {
1237 error = EINVAL;
1238 break;
1239 }
1240 optval = *mtod(m, int *);
1241 {
1242 struct ip6_pktopts **optp;
1243 optp = &inp->inp_outputopts6;
1244 error = ip6_pcbopt(optname, (u_char *)&optval,
1245 sizeof(optval), optp, privileged, uproto);
1246 break;
1247 }
1248
1249 case IPV6_PKTINFO:
1250 case IPV6_HOPOPTS:
1251 case IPV6_RTHDR:
1252 case IPV6_DSTOPTS:
1253 case IPV6_RTHDRDSTOPTS:
1254 {
1255 /* new advanced API (RFC3542) */
1256 u_char *optbuf;
1257 int optbuflen;
1258 struct ip6_pktopts **optp;
1259
1260 if (m && m->m_next) {
1261 error = EINVAL; /* XXX */
1262 break;
1263 }
1264 if (m) {
1265 optbuf = mtod(m, u_char *);
1266 optbuflen = m->m_len;
1267 } else {
1268 optbuf = NULL;
1269 optbuflen = 0;
1270 }
1271 optp = &inp->inp_outputopts6;
1272 error = ip6_pcbopt(optname, optbuf, optbuflen, optp,
1273 privileged, uproto);
1274 break;
1275 }
1276 #undef OPTSET
1277
1278 case IPV6_MULTICAST_IF:
1279 case IPV6_MULTICAST_HOPS:
1280 case IPV6_MULTICAST_LOOP:
1281 case IPV6_JOIN_GROUP:
1282 case IPV6_LEAVE_GROUP:
1283 error = ip6_setmoptions(optname,
1284 &inp->inp_moptions6,
1285 m, inp->inp_rtableid);
1286 break;
1287
1288 case IPV6_PORTRANGE:
1289 if (m == NULL || m->m_len != sizeof(int)) {
1290 error = EINVAL;
1291 break;
1292 }
1293 optval = *mtod(m, int *);
1294
1295 switch (optval) {
1296 case IPV6_PORTRANGE_DEFAULT:
1297 inp->inp_flags &= ~(IN6P_LOWPORT);
1298 inp->inp_flags &= ~(IN6P_HIGHPORT);
1299 break;
1300
1301 case IPV6_PORTRANGE_HIGH:
1302 inp->inp_flags &= ~(IN6P_LOWPORT);
1303 inp->inp_flags |= IN6P_HIGHPORT;
1304 break;
1305
1306 case IPV6_PORTRANGE_LOW:
1307 inp->inp_flags &= ~(IN6P_HIGHPORT);
1308 inp->inp_flags |= IN6P_LOWPORT;
1309 break;
1310
1311 default:
1312 error = EINVAL;
1313 break;
1314 }
1315 break;
1316
1317 case IPSEC6_OUTSA:
1318 error = EINVAL;
1319 break;
1320
1321 case IPV6_AUTH_LEVEL:
1322 case IPV6_ESP_TRANS_LEVEL:
1323 case IPV6_ESP_NETWORK_LEVEL:
1324 case IPV6_IPCOMP_LEVEL:
1325 #ifndef IPSEC
1326 error = EINVAL;
1327 #else
1328 if (m == NULL || m->m_len != sizeof(int)) {
1329 error = EINVAL;
1330 break;
1331 }
1332 optval = *mtod(m, int *);
1333
1334 if (optval < IPSEC_LEVEL_BYPASS ||
1335 optval > IPSEC_LEVEL_UNIQUE) {
1336 error = EINVAL;
1337 break;
1338 }
1339
1340 switch (optname) {
1341 case IPV6_AUTH_LEVEL:
1342 if (optval < IPSEC_AUTH_LEVEL_DEFAULT &&
1343 suser(p)) {
1344 error = EACCES;
1345 break;
1346 }
1347 inp->inp_seclevel[SL_AUTH] = optval;
1348 break;
1349
1350 case IPV6_ESP_TRANS_LEVEL:
1351 if (optval < IPSEC_ESP_TRANS_LEVEL_DEFAULT &&
1352 suser(p)) {
1353 error = EACCES;
1354 break;
1355 }
1356 inp->inp_seclevel[SL_ESP_TRANS] = optval;
1357 break;
1358
1359 case IPV6_ESP_NETWORK_LEVEL:
1360 if (optval < IPSEC_ESP_NETWORK_LEVEL_DEFAULT &&
1361 suser(p)) {
1362 error = EACCES;
1363 break;
1364 }
1365 inp->inp_seclevel[SL_ESP_NETWORK] = optval;
1366 break;
1367
1368 case IPV6_IPCOMP_LEVEL:
1369 if (optval < IPSEC_IPCOMP_LEVEL_DEFAULT &&
1370 suser(p)) {
1371 error = EACCES;
1372 break;
1373 }
1374 inp->inp_seclevel[SL_IPCOMP] = optval;
1375 break;
1376 }
1377 #endif
1378 break;
1379 case SO_RTABLE:
1380 if (m == NULL || m->m_len < sizeof(u_int)) {
1381 error = EINVAL;
1382 break;
1383 }
1384 rtid = *mtod(m, u_int *);
1385 if (inp->inp_rtableid == rtid)
1386 break;
1387 /* needs privileges to switch when already set */
1388 if (rtableid != rtid && rtableid != 0 &&
1389 (error = suser(p)) != 0)
1390 break;
1391 /* table must exist */
1392 if (!rtable_exists(rtid)) {
1393 error = EINVAL;
1394 break;
1395 }
1396 if (inp->inp_lport) {
1397 error = EBUSY;
1398 break;
1399 }
1400 inp->inp_rtableid = rtid;
1401 in_pcbrehash(inp);
1402 break;
1403 case IPV6_PIPEX:
1404 if (m != NULL && m->m_len == sizeof(int))
1405 inp->inp_pipex = *mtod(m, int *);
1406 else
1407 error = EINVAL;
1408 break;
1409
1410 default:
1411 error = ENOPROTOOPT;
1412 break;
1413 }
1414 break;
1415
1416 case PRCO_GETOPT:
1417 switch (optname) {
1418
1419 case IPV6_RECVHOPOPTS:
1420 case IPV6_RECVDSTOPTS:
1421 case IPV6_UNICAST_HOPS:
1422 case IPV6_MINHOPCOUNT:
1423 case IPV6_RECVPKTINFO:
1424 case IPV6_RECVHOPLIMIT:
1425 case IPV6_RECVRTHDR:
1426 case IPV6_RECVPATHMTU:
1427
1428 case IPV6_V6ONLY:
1429 case IPV6_PORTRANGE:
1430 case IPV6_RECVTCLASS:
1431 case IPV6_AUTOFLOWLABEL:
1432 case IPV6_RECVDSTPORT:
1433 switch (optname) {
1434
1435 case IPV6_RECVHOPOPTS:
1436 optval = OPTBIT(IN6P_HOPOPTS);
1437 break;
1438
1439 case IPV6_RECVDSTOPTS:
1440 optval = OPTBIT(IN6P_DSTOPTS);
1441 break;
1442
1443 case IPV6_UNICAST_HOPS:
1444 optval = inp->inp_hops;
1445 break;
1446
1447 case IPV6_MINHOPCOUNT:
1448 optval = inp->inp_ip6_minhlim;
1449 break;
1450
1451 case IPV6_RECVPKTINFO:
1452 optval = OPTBIT(IN6P_PKTINFO);
1453 break;
1454
1455 case IPV6_RECVHOPLIMIT:
1456 optval = OPTBIT(IN6P_HOPLIMIT);
1457 break;
1458
1459 case IPV6_RECVRTHDR:
1460 optval = OPTBIT(IN6P_RTHDR);
1461 break;
1462
1463 case IPV6_RECVPATHMTU:
1464 optval = OPTBIT(IN6P_MTU);
1465 break;
1466
1467 case IPV6_V6ONLY:
1468 optval = 1;
1469 break;
1470
1471 case IPV6_PORTRANGE:
1472 {
1473 int flags;
1474 flags = inp->inp_flags;
1475 if (flags & IN6P_HIGHPORT)
1476 optval = IPV6_PORTRANGE_HIGH;
1477 else if (flags & IN6P_LOWPORT)
1478 optval = IPV6_PORTRANGE_LOW;
1479 else
1480 optval = 0;
1481 break;
1482 }
1483 case IPV6_RECVTCLASS:
1484 optval = OPTBIT(IN6P_TCLASS);
1485 break;
1486
1487 case IPV6_AUTOFLOWLABEL:
1488 optval = OPTBIT(IN6P_AUTOFLOWLABEL);
1489 break;
1490
1491 case IPV6_RECVDSTPORT:
1492 optval = OPTBIT(IN6P_RECVDSTPORT);
1493 break;
1494 }
1495 if (error)
1496 break;
1497 m->m_len = sizeof(int);
1498 *mtod(m, int *) = optval;
1499 break;
1500
1501 case IPV6_PATHMTU:
1502 {
1503 u_long pmtu = 0;
1504 struct ip6_mtuinfo mtuinfo;
1505 struct ifnet *ifp;
1506 struct rtentry *rt;
1507
1508 if (!(so->so_state & SS_ISCONNECTED))
1509 return (ENOTCONN);
1510
1511 rt = in_pcbrtentry(inp);
1512 if (!rtisvalid(rt))
1513 return (EHOSTUNREACH);
1514
1515 ifp = if_get(rt->rt_ifidx);
1516 if (ifp == NULL)
1517 return (EHOSTUNREACH);
1518 /*
1519 * XXX: we dot not consider the case of source
1520 * routing, or optional information to specify
1521 * the outgoing interface.
1522 */
1523 error = ip6_getpmtu(rt, ifp, &pmtu);
1524 if_put(ifp);
1525 if (error)
1526 break;
1527 if (pmtu > IPV6_MAXPACKET)
1528 pmtu = IPV6_MAXPACKET;
1529
1530 bzero(&mtuinfo, sizeof(mtuinfo));
1531 mtuinfo.ip6m_mtu = (u_int32_t)pmtu;
1532 optdata = (void *)&mtuinfo;
1533 optdatalen = sizeof(mtuinfo);
1534 if (optdatalen > MCLBYTES)
1535 return (EMSGSIZE); /* XXX */
1536 if (optdatalen > MLEN)
1537 MCLGET(m, M_WAIT);
1538 m->m_len = optdatalen;
1539 bcopy(optdata, mtod(m, void *), optdatalen);
1540 break;
1541 }
1542
1543 case IPV6_PKTINFO:
1544 case IPV6_HOPOPTS:
1545 case IPV6_RTHDR:
1546 case IPV6_DSTOPTS:
1547 case IPV6_RTHDRDSTOPTS:
1548 case IPV6_TCLASS:
1549 case IPV6_DONTFRAG:
1550 case IPV6_USE_MIN_MTU:
1551 error = ip6_getpcbopt(inp->inp_outputopts6,
1552 optname, m);
1553 break;
1554
1555 case IPV6_MULTICAST_IF:
1556 case IPV6_MULTICAST_HOPS:
1557 case IPV6_MULTICAST_LOOP:
1558 case IPV6_JOIN_GROUP:
1559 case IPV6_LEAVE_GROUP:
1560 error = ip6_getmoptions(optname,
1561 inp->inp_moptions6, m);
1562 break;
1563
1564 case IPSEC6_OUTSA:
1565 error = EINVAL;
1566 break;
1567
1568 case IPV6_AUTH_LEVEL:
1569 case IPV6_ESP_TRANS_LEVEL:
1570 case IPV6_ESP_NETWORK_LEVEL:
1571 case IPV6_IPCOMP_LEVEL:
1572 #ifndef IPSEC
1573 m->m_len = sizeof(int);
1574 *mtod(m, int *) = IPSEC_LEVEL_NONE;
1575 #else
1576 m->m_len = sizeof(int);
1577 switch (optname) {
1578 case IPV6_AUTH_LEVEL:
1579 optval = inp->inp_seclevel[SL_AUTH];
1580 break;
1581
1582 case IPV6_ESP_TRANS_LEVEL:
1583 optval =
1584 inp->inp_seclevel[SL_ESP_TRANS];
1585 break;
1586
1587 case IPV6_ESP_NETWORK_LEVEL:
1588 optval =
1589 inp->inp_seclevel[SL_ESP_NETWORK];
1590 break;
1591
1592 case IPV6_IPCOMP_LEVEL:
1593 optval = inp->inp_seclevel[SL_IPCOMP];
1594 break;
1595 }
1596 *mtod(m, int *) = optval;
1597 #endif
1598 break;
1599 case SO_RTABLE:
1600 m->m_len = sizeof(u_int);
1601 *mtod(m, u_int *) = inp->inp_rtableid;
1602 break;
1603 case IPV6_PIPEX:
1604 m->m_len = sizeof(int);
1605 *mtod(m, int *) = inp->inp_pipex;
1606 break;
1607
1608 default:
1609 error = ENOPROTOOPT;
1610 break;
1611 }
1612 break;
1613 }
1614 return (error);
1615 }
1616
1617 int
1618 ip6_raw_ctloutput(int op, struct socket *so, int level, int optname,
1619 struct mbuf *m)
1620 {
1621 int error = 0, optval;
1622 const int icmp6off = offsetof(struct icmp6_hdr, icmp6_cksum);
1623 struct inpcb *inp = sotoinpcb(so);
1624
1625 if (level != IPPROTO_IPV6)
1626 return (EINVAL);
1627
1628 switch (optname) {
1629 case IPV6_CHECKSUM:
1630 /*
1631 * For ICMPv6 sockets, no modification allowed for checksum
1632 * offset, permit "no change" values to help existing apps.
1633 *
1634 * RFC3542 says: "An attempt to set IPV6_CHECKSUM
1635 * for an ICMPv6 socket will fail."
1636 * The current behavior does not meet RFC3542.
1637 */
1638 switch (op) {
1639 case PRCO_SETOPT:
1640 if (m == NULL || m->m_len != sizeof(int)) {
1641 error = EINVAL;
1642 break;
1643 }
1644 optval = *mtod(m, int *);
1645 if (optval < -1 ||
1646 (optval > 0 && (optval % 2) != 0)) {
1647 /*
1648 * The API assumes non-negative even offset
1649 * values or -1 as a special value.
1650 */
1651 error = EINVAL;
1652 } else if (so->so_proto->pr_protocol ==
1653 IPPROTO_ICMPV6) {
1654 if (optval != icmp6off)
1655 error = EINVAL;
1656 } else
1657 inp->inp_cksum6 = optval;
1658 break;
1659
1660 case PRCO_GETOPT:
1661 if (so->so_proto->pr_protocol == IPPROTO_ICMPV6)
1662 optval = icmp6off;
1663 else
1664 optval = inp->inp_cksum6;
1665
1666 m->m_len = sizeof(int);
1667 *mtod(m, int *) = optval;
1668 break;
1669
1670 default:
1671 error = EINVAL;
1672 break;
1673 }
1674 break;
1675
1676 default:
1677 error = ENOPROTOOPT;
1678 break;
1679 }
1680
1681 return (error);
1682 }
1683
1684 /*
1685 * initialize ip6_pktopts. beware that there are non-zero default values in
1686 * the struct.
1687 */
1688 void
1689 ip6_initpktopts(struct ip6_pktopts *opt)
1690 {
1691 bzero(opt, sizeof(*opt));
1692 opt->ip6po_hlim = -1; /* -1 means default hop limit */
1693 opt->ip6po_tclass = -1; /* -1 means default traffic class */
1694 opt->ip6po_minmtu = IP6PO_MINMTU_MCASTONLY;
1695 }
1696
1697 int
1698 ip6_pcbopt(int optname, u_char *buf, int len, struct ip6_pktopts **pktopt,
1699 int priv, int uproto)
1700 {
1701 struct ip6_pktopts *opt;
1702
1703 if (*pktopt == NULL) {
1704 *pktopt = malloc(sizeof(struct ip6_pktopts), M_IP6OPT,
1705 M_WAITOK);
1706 ip6_initpktopts(*pktopt);
1707 }
1708 opt = *pktopt;
1709
1710 return (ip6_setpktopt(optname, buf, len, opt, priv, 1, uproto));
1711 }
1712
1713 int
1714 ip6_getpcbopt(struct ip6_pktopts *pktopt, int optname, struct mbuf *m)
1715 {
1716 void *optdata = NULL;
1717 int optdatalen = 0;
1718 struct ip6_ext *ip6e;
1719 int error = 0;
1720 struct in6_pktinfo null_pktinfo;
1721 int deftclass = 0, on;
1722 int defminmtu = IP6PO_MINMTU_MCASTONLY;
1723
1724 switch (optname) {
1725 case IPV6_PKTINFO:
1726 if (pktopt && pktopt->ip6po_pktinfo)
1727 optdata = (void *)pktopt->ip6po_pktinfo;
1728 else {
1729 /* XXX: we don't have to do this every time... */
1730 bzero(&null_pktinfo, sizeof(null_pktinfo));
1731 optdata = (void *)&null_pktinfo;
1732 }
1733 optdatalen = sizeof(struct in6_pktinfo);
1734 break;
1735 case IPV6_TCLASS:
1736 if (pktopt && pktopt->ip6po_tclass >= 0)
1737 optdata = (void *)&pktopt->ip6po_tclass;
1738 else
1739 optdata = (void *)&deftclass;
1740 optdatalen = sizeof(int);
1741 break;
1742 case IPV6_HOPOPTS:
1743 if (pktopt && pktopt->ip6po_hbh) {
1744 optdata = (void *)pktopt->ip6po_hbh;
1745 ip6e = (struct ip6_ext *)pktopt->ip6po_hbh;
1746 optdatalen = (ip6e->ip6e_len + 1) << 3;
1747 }
1748 break;
1749 case IPV6_RTHDR:
1750 if (pktopt && pktopt->ip6po_rthdr) {
1751 optdata = (void *)pktopt->ip6po_rthdr;
1752 ip6e = (struct ip6_ext *)pktopt->ip6po_rthdr;
1753 optdatalen = (ip6e->ip6e_len + 1) << 3;
1754 }
1755 break;
1756 case IPV6_RTHDRDSTOPTS:
1757 if (pktopt && pktopt->ip6po_dest1) {
1758 optdata = (void *)pktopt->ip6po_dest1;
1759 ip6e = (struct ip6_ext *)pktopt->ip6po_dest1;
1760 optdatalen = (ip6e->ip6e_len + 1) << 3;
1761 }
1762 break;
1763 case IPV6_DSTOPTS:
1764 if (pktopt && pktopt->ip6po_dest2) {
1765 optdata = (void *)pktopt->ip6po_dest2;
1766 ip6e = (struct ip6_ext *)pktopt->ip6po_dest2;
1767 optdatalen = (ip6e->ip6e_len + 1) << 3;
1768 }
1769 break;
1770 case IPV6_USE_MIN_MTU:
1771 if (pktopt)
1772 optdata = (void *)&pktopt->ip6po_minmtu;
1773 else
1774 optdata = (void *)&defminmtu;
1775 optdatalen = sizeof(int);
1776 break;
1777 case IPV6_DONTFRAG:
1778 if (pktopt && ((pktopt->ip6po_flags) & IP6PO_DONTFRAG))
1779 on = 1;
1780 else
1781 on = 0;
1782 optdata = (void *)&on;
1783 optdatalen = sizeof(on);
1784 break;
1785 default: /* should not happen */
1786 #ifdef DIAGNOSTIC
1787 panic("%s: unexpected option", __func__);
1788 #endif
1789 return (ENOPROTOOPT);
1790 }
1791
1792 if (optdatalen > MCLBYTES)
1793 return (EMSGSIZE); /* XXX */
1794 if (optdatalen > MLEN)
1795 MCLGET(m, M_WAIT);
1796 m->m_len = optdatalen;
1797 if (optdatalen)
1798 bcopy(optdata, mtod(m, void *), optdatalen);
1799
1800 return (error);
1801 }
1802
1803 void
1804 ip6_clearpktopts(struct ip6_pktopts *pktopt, int optname)
1805 {
1806 if (optname == -1 || optname == IPV6_PKTINFO) {
1807 if (pktopt->ip6po_pktinfo)
1808 free(pktopt->ip6po_pktinfo, M_IP6OPT, 0);
1809 pktopt->ip6po_pktinfo = NULL;
1810 }
1811 if (optname == -1 || optname == IPV6_HOPLIMIT)
1812 pktopt->ip6po_hlim = -1;
1813 if (optname == -1 || optname == IPV6_TCLASS)
1814 pktopt->ip6po_tclass = -1;
1815 if (optname == -1 || optname == IPV6_HOPOPTS) {
1816 if (pktopt->ip6po_hbh)
1817 free(pktopt->ip6po_hbh, M_IP6OPT, 0);
1818 pktopt->ip6po_hbh = NULL;
1819 }
1820 if (optname == -1 || optname == IPV6_RTHDRDSTOPTS) {
1821 if (pktopt->ip6po_dest1)
1822 free(pktopt->ip6po_dest1, M_IP6OPT, 0);
1823 pktopt->ip6po_dest1 = NULL;
1824 }
1825 if (optname == -1 || optname == IPV6_RTHDR) {
1826 if (pktopt->ip6po_rhinfo.ip6po_rhi_rthdr)
1827 free(pktopt->ip6po_rhinfo.ip6po_rhi_rthdr, M_IP6OPT, 0);
1828 pktopt->ip6po_rhinfo.ip6po_rhi_rthdr = NULL;
1829 if (pktopt->ip6po_route.ro_rt) {
1830 rtfree(pktopt->ip6po_route.ro_rt);
1831 pktopt->ip6po_route.ro_rt = NULL;
1832 }
1833 }
1834 if (optname == -1 || optname == IPV6_DSTOPTS) {
1835 if (pktopt->ip6po_dest2)
1836 free(pktopt->ip6po_dest2, M_IP6OPT, 0);
1837 pktopt->ip6po_dest2 = NULL;
1838 }
1839 }
1840
1841 #define PKTOPT_EXTHDRCPY(type) \
1842 do {\
1843 if (src->type) {\
1844 size_t hlen;\
1845 hlen = (((struct ip6_ext *)src->type)->ip6e_len + 1) << 3;\
1846 dst->type = malloc(hlen, M_IP6OPT, M_NOWAIT);\
1847 if (dst->type == NULL)\
1848 goto bad;\
1849 memcpy(dst->type, src->type, hlen);\
1850 }\
1851 } while (/*CONSTCOND*/ 0)
1852
1853 int
1854 copypktopts(struct ip6_pktopts *dst, struct ip6_pktopts *src)
1855 {
1856 dst->ip6po_hlim = src->ip6po_hlim;
1857 dst->ip6po_tclass = src->ip6po_tclass;
1858 dst->ip6po_flags = src->ip6po_flags;
1859 if (src->ip6po_pktinfo) {
1860 dst->ip6po_pktinfo = malloc(sizeof(*dst->ip6po_pktinfo),
1861 M_IP6OPT, M_NOWAIT);
1862 if (dst->ip6po_pktinfo == NULL)
1863 goto bad;
1864 *dst->ip6po_pktinfo = *src->ip6po_pktinfo;
1865 }
1866 PKTOPT_EXTHDRCPY(ip6po_hbh);
1867 PKTOPT_EXTHDRCPY(ip6po_dest1);
1868 PKTOPT_EXTHDRCPY(ip6po_dest2);
1869 PKTOPT_EXTHDRCPY(ip6po_rthdr); /* not copy the cached route */
1870 return (0);
1871
1872 bad:
1873 ip6_clearpktopts(dst, -1);
1874 return (ENOBUFS);
1875 }
1876 #undef PKTOPT_EXTHDRCPY
1877
1878 void
1879 ip6_freepcbopts(struct ip6_pktopts *pktopt)
1880 {
1881 if (pktopt == NULL)
1882 return;
1883
1884 ip6_clearpktopts(pktopt, -1);
1885
1886 free(pktopt, M_IP6OPT, 0);
1887 }
1888
1889 /*
1890 * Set the IP6 multicast options in response to user setsockopt().
1891 */
1892 int
1893 ip6_setmoptions(int optname, struct ip6_moptions **im6op, struct mbuf *m,
1894 unsigned int rtableid)
1895 {
1896 int error = 0;
1897 u_int loop, ifindex;
1898 struct ipv6_mreq *mreq;
1899 struct ifnet *ifp;
1900 struct ip6_moptions *im6o = *im6op;
1901 struct in6_multi_mship *imm;
1902 struct proc *p = curproc; /* XXX */
1903
1904 if (im6o == NULL) {
1905 /*
1906 * No multicast option buffer attached to the pcb;
1907 * allocate one and initialize to default values.
1908 */
1909 im6o = malloc(sizeof(*im6o), M_IPMOPTS, M_WAITOK);
1910 if (im6o == NULL)
1911 return (ENOBUFS);
1912 *im6op = im6o;
1913 im6o->im6o_ifidx = 0;
1914 im6o->im6o_hlim = ip6_defmcasthlim;
1915 im6o->im6o_loop = IPV6_DEFAULT_MULTICAST_LOOP;
1916 LIST_INIT(&im6o->im6o_memberships);
1917 }
1918
1919 switch (optname) {
1920
1921 case IPV6_MULTICAST_IF:
1922 /*
1923 * Select the interface for outgoing multicast packets.
1924 */
1925 if (m == NULL || m->m_len != sizeof(u_int)) {
1926 error = EINVAL;
1927 break;
1928 }
1929 memcpy(&ifindex, mtod(m, u_int *), sizeof(ifindex));
1930 if (ifindex != 0) {
1931 ifp = if_get(ifindex);
1932 if (ifp == NULL) {
1933 error = ENXIO; /* XXX EINVAL? */
1934 break;
1935 }
1936 if (ifp->if_rdomain != rtable_l2(rtableid) ||
1937 (ifp->if_flags & IFF_MULTICAST) == 0) {
1938 error = EADDRNOTAVAIL;
1939 if_put(ifp);
1940 break;
1941 }
1942 if_put(ifp);
1943 }
1944 im6o->im6o_ifidx = ifindex;
1945 break;
1946
1947 case IPV6_MULTICAST_HOPS:
1948 {
1949 /*
1950 * Set the IP6 hoplimit for outgoing multicast packets.
1951 */
1952 int optval;
1953 if (m == NULL || m->m_len != sizeof(int)) {
1954 error = EINVAL;
1955 break;
1956 }
1957 memcpy(&optval, mtod(m, u_int *), sizeof(optval));
1958 if (optval < -1 || optval >= 256)
1959 error = EINVAL;
1960 else if (optval == -1)
1961 im6o->im6o_hlim = ip6_defmcasthlim;
1962 else
1963 im6o->im6o_hlim = optval;
1964 break;
1965 }
1966
1967 case IPV6_MULTICAST_LOOP:
1968 /*
1969 * Set the loopback flag for outgoing multicast packets.
1970 * Must be zero or one.
1971 */
1972 if (m == NULL || m->m_len != sizeof(u_int)) {
1973 error = EINVAL;
1974 break;
1975 }
1976 memcpy(&loop, mtod(m, u_int *), sizeof(loop));
1977 if (loop > 1) {
1978 error = EINVAL;
1979 break;
1980 }
1981 im6o->im6o_loop = loop;
1982 break;
1983
1984 case IPV6_JOIN_GROUP:
1985 /*
1986 * Add a multicast group membership.
1987 * Group must be a valid IP6 multicast address.
1988 */
1989 if (m == NULL || m->m_len != sizeof(struct ipv6_mreq)) {
1990 error = EINVAL;
1991 break;
1992 }
1993 mreq = mtod(m, struct ipv6_mreq *);
1994 if (IN6_IS_ADDR_UNSPECIFIED(&mreq->ipv6mr_multiaddr)) {
1995 /*
1996 * We use the unspecified address to specify to accept
1997 * all multicast addresses. Only super user is allowed
1998 * to do this.
1999 */
2000 if (suser(p))
2001 {
2002 error = EACCES;
2003 break;
2004 }
2005 } else if (!IN6_IS_ADDR_MULTICAST(&mreq->ipv6mr_multiaddr)) {
2006 error = EINVAL;
2007 break;
2008 }
2009
2010 /*
2011 * If no interface was explicitly specified, choose an
2012 * appropriate one according to the given multicast address.
2013 */
2014 if (mreq->ipv6mr_interface == 0) {
2015 struct rtentry *rt;
2016 struct sockaddr_in6 dst;
2017
2018 memset(&dst, 0, sizeof(dst));
2019 dst.sin6_len = sizeof(dst);
2020 dst.sin6_family = AF_INET6;
2021 dst.sin6_addr = mreq->ipv6mr_multiaddr;
2022 rt = rtalloc(sin6tosa(&dst), RT_RESOLVE, rtableid);
2023 if (rt == NULL) {
2024 error = EADDRNOTAVAIL;
2025 break;
2026 }
2027 ifp = if_get(rt->rt_ifidx);
2028 rtfree(rt);
2029 } else {
2030 /*
2031 * If the interface is specified, validate it.
2032 */
2033 ifp = if_get(mreq->ipv6mr_interface);
2034 if (ifp == NULL) {
2035 error = ENXIO; /* XXX EINVAL? */
2036 break;
2037 }
2038 }
2039
2040 /*
2041 * See if we found an interface, and confirm that it
2042 * supports multicast
2043 */
2044 if (ifp == NULL || ifp->if_rdomain != rtable_l2(rtableid) ||
2045 (ifp->if_flags & IFF_MULTICAST) == 0) {
2046 if_put(ifp);
2047 error = EADDRNOTAVAIL;
2048 break;
2049 }
2050 /*
2051 * Put interface index into the multicast address,
2052 * if the address has link/interface-local scope.
2053 */
2054 if (IN6_IS_SCOPE_EMBED(&mreq->ipv6mr_multiaddr)) {
2055 mreq->ipv6mr_multiaddr.s6_addr16[1] =
2056 htons(ifp->if_index);
2057 }
2058 /*
2059 * See if the membership already exists.
2060 */
2061 LIST_FOREACH(imm, &im6o->im6o_memberships, i6mm_chain)
2062 if (imm->i6mm_maddr->in6m_ifidx == ifp->if_index &&
2063 IN6_ARE_ADDR_EQUAL(&imm->i6mm_maddr->in6m_addr,
2064 &mreq->ipv6mr_multiaddr))
2065 break;
2066 if (imm != NULL) {
2067 if_put(ifp);
2068 error = EADDRINUSE;
2069 break;
2070 }
2071 /*
2072 * Everything looks good; add a new record to the multicast
2073 * address list for the given interface.
2074 */
2075 imm = in6_joingroup(ifp, &mreq->ipv6mr_multiaddr, &error);
2076 if_put(ifp);
2077 if (!imm)
2078 break;
2079 LIST_INSERT_HEAD(&im6o->im6o_memberships, imm, i6mm_chain);
2080 break;
2081
2082 case IPV6_LEAVE_GROUP:
2083 /*
2084 * Drop a multicast group membership.
2085 * Group must be a valid IP6 multicast address.
2086 */
2087 if (m == NULL || m->m_len != sizeof(struct ipv6_mreq)) {
2088 error = EINVAL;
2089 break;
2090 }
2091 mreq = mtod(m, struct ipv6_mreq *);
2092 if (IN6_IS_ADDR_UNSPECIFIED(&mreq->ipv6mr_multiaddr)) {
2093 if (suser(p)) {
2094 error = EACCES;
2095 break;
2096 }
2097 } else if (!IN6_IS_ADDR_MULTICAST(&mreq->ipv6mr_multiaddr)) {
2098 error = EINVAL;
2099 break;
2100 }
2101
2102 /*
2103 * Put interface index into the multicast address,
2104 * if the address has link-local scope.
2105 */
2106 if (IN6_IS_ADDR_MC_LINKLOCAL(&mreq->ipv6mr_multiaddr)) {
2107 mreq->ipv6mr_multiaddr.s6_addr16[1] =
2108 htons(mreq->ipv6mr_interface);
2109 }
2110
2111 /*
2112 * If an interface address was specified, get a pointer
2113 * to its ifnet structure.
2114 */
2115 if (mreq->ipv6mr_interface == 0)
2116 ifp = NULL;
2117 else {
2118 ifp = if_get(mreq->ipv6mr_interface);
2119 if (ifp == NULL) {
2120 error = ENXIO; /* XXX EINVAL? */
2121 break;
2122 }
2123 }
2124
2125 /*
2126 * Find the membership in the membership list.
2127 */
2128 LIST_FOREACH(imm, &im6o->im6o_memberships, i6mm_chain) {
2129 if ((ifp == NULL ||
2130 imm->i6mm_maddr->in6m_ifidx == ifp->if_index) &&
2131 IN6_ARE_ADDR_EQUAL(&imm->i6mm_maddr->in6m_addr,
2132 &mreq->ipv6mr_multiaddr))
2133 break;
2134 }
2135
2136 if_put(ifp);
2137
2138 if (imm == NULL) {
2139 /* Unable to resolve interface */
2140 error = EADDRNOTAVAIL;
2141 break;
2142 }
2143 /*
2144 * Give up the multicast address record to which the
2145 * membership points.
2146 */
2147 LIST_REMOVE(imm, i6mm_chain);
2148 in6_leavegroup(imm);
2149 break;
2150
2151 default:
2152 error = EOPNOTSUPP;
2153 break;
2154 }
2155
2156 /*
2157 * If all options have default values, no need to keep the option
2158 * structure.
2159 */
2160 if (im6o->im6o_ifidx == 0 &&
2161 im6o->im6o_hlim == ip6_defmcasthlim &&
2162 im6o->im6o_loop == IPV6_DEFAULT_MULTICAST_LOOP &&
2163 LIST_EMPTY(&im6o->im6o_memberships)) {
2164 free(*im6op, M_IPMOPTS, sizeof(**im6op));
2165 *im6op = NULL;
2166 }
2167
2168 return (error);
2169 }
2170
2171 /*
2172 * Return the IP6 multicast options in response to user getsockopt().
2173 */
2174 int
2175 ip6_getmoptions(int optname, struct ip6_moptions *im6o, struct mbuf *m)
2176 {
2177 u_int *hlim, *loop, *ifindex;
2178
2179 switch (optname) {
2180 case IPV6_MULTICAST_IF:
2181 ifindex = mtod(m, u_int *);
2182 m->m_len = sizeof(u_int);
2183 if (im6o == NULL || im6o->im6o_ifidx == 0)
2184 *ifindex = 0;
2185 else
2186 *ifindex = im6o->im6o_ifidx;
2187 return (0);
2188
2189 case IPV6_MULTICAST_HOPS:
2190 hlim = mtod(m, u_int *);
2191 m->m_len = sizeof(u_int);
2192 if (im6o == NULL)
2193 *hlim = ip6_defmcasthlim;
2194 else
2195 *hlim = im6o->im6o_hlim;
2196 return (0);
2197
2198 case IPV6_MULTICAST_LOOP:
2199 loop = mtod(m, u_int *);
2200 m->m_len = sizeof(u_int);
2201 if (im6o == NULL)
2202 *loop = ip6_defmcasthlim;
2203 else
2204 *loop = im6o->im6o_loop;
2205 return (0);
2206
2207 default:
2208 return (EOPNOTSUPP);
2209 }
2210 }
2211
2212 /*
2213 * Discard the IP6 multicast options.
2214 */
2215 void
2216 ip6_freemoptions(struct ip6_moptions *im6o)
2217 {
2218 struct in6_multi_mship *imm;
2219
2220 if (im6o == NULL)
2221 return;
2222
2223 while (!LIST_EMPTY(&im6o->im6o_memberships)) {
2224 imm = LIST_FIRST(&im6o->im6o_memberships);
2225 LIST_REMOVE(imm, i6mm_chain);
2226 in6_leavegroup(imm);
2227 }
2228 free(im6o, M_IPMOPTS, sizeof(*im6o));
2229 }
2230
2231 /*
2232 * Set IPv6 outgoing packet options based on advanced API.
2233 */
2234 int
2235 ip6_setpktopts(struct mbuf *control, struct ip6_pktopts *opt,
2236 struct ip6_pktopts *stickyopt, int priv, int uproto)
2237 {
2238 u_int clen;
2239 struct cmsghdr *cm = 0;
2240 caddr_t cmsgs;
2241 int error;
2242
2243 if (control == NULL || opt == NULL)
2244 return (EINVAL);
2245
2246 ip6_initpktopts(opt);
2247 if (stickyopt) {
2248 int error;
2249
2250 /*
2251 * If stickyopt is provided, make a local copy of the options
2252 * for this particular packet, then override them by ancillary
2253 * objects.
2254 * XXX: copypktopts() does not copy the cached route to a next
2255 * hop (if any). This is not very good in terms of efficiency,
2256 * but we can allow this since this option should be rarely
2257 * used.
2258 */
2259 if ((error = copypktopts(opt, stickyopt)) != 0)
2260 return (error);
2261 }
2262
2263 /*
2264 * XXX: Currently, we assume all the optional information is stored
2265 * in a single mbuf.
2266 */
2267 if (control->m_next)
2268 return (EINVAL);
2269
2270 clen = control->m_len;
2271 cmsgs = mtod(control, caddr_t);
2272 do {
2273 if (clen < CMSG_LEN(0))
2274 return (EINVAL);
2275 cm = (struct cmsghdr *)cmsgs;
2276 if (cm->cmsg_len < CMSG_LEN(0) || cm->cmsg_len > clen ||
2277 CMSG_ALIGN(cm->cmsg_len) > clen)
2278 return (EINVAL);
2279 if (cm->cmsg_level == IPPROTO_IPV6) {
2280 error = ip6_setpktopt(cm->cmsg_type, CMSG_DATA(cm),
2281 cm->cmsg_len - CMSG_LEN(0), opt, priv, 0, uproto);
2282 if (error)
2283 return (error);
2284 }
2285
2286 clen -= CMSG_ALIGN(cm->cmsg_len);
2287 cmsgs += CMSG_ALIGN(cm->cmsg_len);
2288 } while (clen);
2289
2290 return (0);
2291 }
2292
2293 /*
2294 * Set a particular packet option, as a sticky option or an ancillary data
2295 * item. "len" can be 0 only when it's a sticky option.
2296 */
2297 int
2298 ip6_setpktopt(int optname, u_char *buf, int len, struct ip6_pktopts *opt,
2299 int priv, int sticky, int uproto)
2300 {
2301 int minmtupolicy;
2302
2303 switch (optname) {
2304 case IPV6_PKTINFO:
2305 {
2306 struct ifnet *ifp = NULL;
2307 struct in6_pktinfo *pktinfo;
2308
2309 if (len != sizeof(struct in6_pktinfo))
2310 return (EINVAL);
2311
2312 pktinfo = (struct in6_pktinfo *)buf;
2313
2314 /*
2315 * An application can clear any sticky IPV6_PKTINFO option by
2316 * doing a "regular" setsockopt with ipi6_addr being
2317 * in6addr_any and ipi6_ifindex being zero.
2318 * [RFC 3542, Section 6]
2319 */
2320 if (opt->ip6po_pktinfo &&
2321 pktinfo->ipi6_ifindex == 0 &&
2322 IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
2323 ip6_clearpktopts(opt, optname);
2324 break;
2325 }
2326
2327 if (uproto == IPPROTO_TCP &&
2328 sticky && !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
2329 return (EINVAL);
2330 }
2331
2332 if (pktinfo->ipi6_ifindex) {
2333 ifp = if_get(pktinfo->ipi6_ifindex);
2334 if (ifp == NULL)
2335 return (ENXIO);
2336 if_put(ifp);
2337 }
2338
2339 /*
2340 * We store the address anyway, and let in6_selectsrc()
2341 * validate the specified address. This is because ipi6_addr
2342 * may not have enough information about its scope zone, and
2343 * we may need additional information (such as outgoing
2344 * interface or the scope zone of a destination address) to
2345 * disambiguate the scope.
2346 * XXX: the delay of the validation may confuse the
2347 * application when it is used as a sticky option.
2348 */
2349 if (opt->ip6po_pktinfo == NULL) {
2350 opt->ip6po_pktinfo = malloc(sizeof(*pktinfo),
2351 M_IP6OPT, M_NOWAIT);
2352 if (opt->ip6po_pktinfo == NULL)
2353 return (ENOBUFS);
2354 }
2355 bcopy(pktinfo, opt->ip6po_pktinfo, sizeof(*pktinfo));
2356 break;
2357 }
2358
2359 case IPV6_HOPLIMIT:
2360 {
2361 int *hlimp;
2362
2363 /*
2364 * RFC 3542 deprecated the usage of sticky IPV6_HOPLIMIT
2365 * to simplify the ordering among hoplimit options.
2366 */
2367 if (sticky)
2368 return (ENOPROTOOPT);
2369
2370 if (len != sizeof(int))
2371 return (EINVAL);
2372 hlimp = (int *)buf;
2373 if (*hlimp < -1 || *hlimp > 255)
2374 return (EINVAL);
2375
2376 opt->ip6po_hlim = *hlimp;
2377 break;
2378 }
2379
2380 case IPV6_TCLASS:
2381 {
2382 int tclass;
2383
2384 if (len != sizeof(int))
2385 return (EINVAL);
2386 tclass = *(int *)buf;
2387 if (tclass < -1 || tclass > 255)
2388 return (EINVAL);
2389
2390 opt->ip6po_tclass = tclass;
2391 break;
2392 }
2393 case IPV6_HOPOPTS:
2394 {
2395 struct ip6_hbh *hbh;
2396 int hbhlen;
2397
2398 /*
2399 * XXX: We don't allow a non-privileged user to set ANY HbH
2400 * options, since per-option restriction has too much
2401 * overhead.
2402 */
2403 if (!priv)
2404 return (EPERM);
2405
2406 if (len == 0) {
2407 ip6_clearpktopts(opt, IPV6_HOPOPTS);
2408 break; /* just remove the option */
2409 }
2410
2411 /* message length validation */
2412 if (len < sizeof(struct ip6_hbh))
2413 return (EINVAL);
2414 hbh = (struct ip6_hbh *)buf;
2415 hbhlen = (hbh->ip6h_len + 1) << 3;
2416 if (len != hbhlen)
2417 return (EINVAL);
2418
2419 /* turn off the previous option, then set the new option. */
2420 ip6_clearpktopts(opt, IPV6_HOPOPTS);
2421 opt->ip6po_hbh = malloc(hbhlen, M_IP6OPT, M_NOWAIT);
2422 if (opt->ip6po_hbh == NULL)
2423 return (ENOBUFS);
2424 memcpy(opt->ip6po_hbh, hbh, hbhlen);
2425
2426 break;
2427 }
2428
2429 case IPV6_DSTOPTS:
2430 case IPV6_RTHDRDSTOPTS:
2431 {
2432 struct ip6_dest *dest, **newdest = NULL;
2433 int destlen;
2434
2435 if (!priv) /* XXX: see the comment for IPV6_HOPOPTS */
2436 return (EPERM);
2437
2438 if (len == 0) {
2439 ip6_clearpktopts(opt, optname);
2440 break; /* just remove the option */
2441 }
2442
2443 /* message length validation */
2444 if (len < sizeof(struct ip6_dest))
2445 return (EINVAL);
2446 dest = (struct ip6_dest *)buf;
2447 destlen = (dest->ip6d_len + 1) << 3;
2448 if (len != destlen)
2449 return (EINVAL);
2450 /*
2451 * Determine the position that the destination options header
2452 * should be inserted; before or after the routing header.
2453 */
2454 switch (optname) {
2455 case IPV6_RTHDRDSTOPTS:
2456 newdest = &opt->ip6po_dest1;
2457 break;
2458 case IPV6_DSTOPTS:
2459 newdest = &opt->ip6po_dest2;
2460 break;
2461 }
2462
2463 /* turn off the previous option, then set the new option. */
2464 ip6_clearpktopts(opt, optname);
2465 *newdest = malloc(destlen, M_IP6OPT, M_NOWAIT);
2466 if (*newdest == NULL)
2467 return (ENOBUFS);
2468 memcpy(*newdest, dest, destlen);
2469
2470 break;
2471 }
2472
2473 case IPV6_RTHDR:
2474 {
2475 struct ip6_rthdr *rth;
2476 int rthlen;
2477
2478 if (len == 0) {
2479 ip6_clearpktopts(opt, IPV6_RTHDR);
2480 break; /* just remove the option */
2481 }
2482
2483 /* message length validation */
2484 if (len < sizeof(struct ip6_rthdr))
2485 return (EINVAL);
2486 rth = (struct ip6_rthdr *)buf;
2487 rthlen = (rth->ip6r_len + 1) << 3;
2488 if (len != rthlen)
2489 return (EINVAL);
2490
2491 switch (rth->ip6r_type) {
2492 case IPV6_RTHDR_TYPE_0:
2493 if (rth->ip6r_len == 0) /* must contain one addr */
2494 return (EINVAL);
2495 if (rth->ip6r_len % 2) /* length must be even */
2496 return (EINVAL);
2497 if (rth->ip6r_len / 2 != rth->ip6r_segleft)
2498 return (EINVAL);
2499 break;
2500 default:
2501 return (EINVAL); /* not supported */
2502 }
2503 /* turn off the previous option */
2504 ip6_clearpktopts(opt, IPV6_RTHDR);
2505 opt->ip6po_rthdr = malloc(rthlen, M_IP6OPT, M_NOWAIT);
2506 if (opt->ip6po_rthdr == NULL)
2507 return (ENOBUFS);
2508 memcpy(opt->ip6po_rthdr, rth, rthlen);
2509 break;
2510 }
2511
2512 case IPV6_USE_MIN_MTU:
2513 if (len != sizeof(int))
2514 return (EINVAL);
2515 minmtupolicy = *(int *)buf;
2516 if (minmtupolicy != IP6PO_MINMTU_MCASTONLY &&
2517 minmtupolicy != IP6PO_MINMTU_DISABLE &&
2518 minmtupolicy != IP6PO_MINMTU_ALL) {
2519 return (EINVAL);
2520 }
2521 opt->ip6po_minmtu = minmtupolicy;
2522 break;
2523
2524 case IPV6_DONTFRAG:
2525 if (len != sizeof(int))
2526 return (EINVAL);
2527
2528 if (uproto == IPPROTO_TCP || *(int *)buf == 0) {
2529 /*
2530 * we ignore this option for TCP sockets.
2531 * (RFC3542 leaves this case unspecified.)
2532 */
2533 opt->ip6po_flags &= ~IP6PO_DONTFRAG;
2534 } else
2535 opt->ip6po_flags |= IP6PO_DONTFRAG;
2536 break;
2537
2538 default:
2539 return (ENOPROTOOPT);
2540 } /* end of switch */
2541
2542 return (0);
2543 }
2544
2545 /*
2546 * Routine called from ip6_output() to loop back a copy of an IP6 multicast
2547 * packet to the input queue of a specified interface.
2548 */
2549 void
2550 ip6_mloopback(struct ifnet *ifp, struct mbuf *m, struct sockaddr_in6 *dst)
2551 {
2552 struct mbuf *copym;
2553 struct ip6_hdr *ip6;
2554
2555 /*
2556 * Duplicate the packet.
2557 */
2558 copym = m_copym(m, 0, M_COPYALL, M_NOWAIT);
2559 if (copym == NULL)
2560 return;
2561
2562 /*
2563 * Make sure to deep-copy IPv6 header portion in case the data
2564 * is in an mbuf cluster, so that we can safely override the IPv6
2565 * header portion later.
2566 */
2567 if ((copym->m_flags & M_EXT) != 0 ||
2568 copym->m_len < sizeof(struct ip6_hdr)) {
2569 copym = m_pullup(copym, sizeof(struct ip6_hdr));
2570 if (copym == NULL)
2571 return;
2572 }
2573
2574 #ifdef DIAGNOSTIC
2575 if (copym->m_len < sizeof(*ip6)) {
2576 m_freem(copym);
2577 return;
2578 }
2579 #endif
2580
2581 ip6 = mtod(copym, struct ip6_hdr *);
2582 if (IN6_IS_SCOPE_EMBED(&ip6->ip6_src))
2583 ip6->ip6_src.s6_addr16[1] = 0;
2584 if (IN6_IS_SCOPE_EMBED(&ip6->ip6_dst))
2585 ip6->ip6_dst.s6_addr16[1] = 0;
2586
2587 if_input_local(ifp, copym, dst->sin6_family);
2588 }
2589
2590 /*
2591 * Chop IPv6 header off from the payload.
2592 */
2593 int
2594 ip6_splithdr(struct mbuf *m, struct ip6_exthdrs *exthdrs)
2595 {
2596 struct mbuf *mh;
2597 struct ip6_hdr *ip6;
2598
2599 ip6 = mtod(m, struct ip6_hdr *);
2600 if (m->m_len > sizeof(*ip6)) {
2601 MGET(mh, M_DONTWAIT, MT_HEADER);
2602 if (mh == NULL) {
2603 m_freem(m);
2604 return ENOBUFS;
2605 }
2606 M_MOVE_PKTHDR(mh, m);
2607 m_align(mh, sizeof(*ip6));
2608 m->m_len -= sizeof(*ip6);
2609 m->m_data += sizeof(*ip6);
2610 mh->m_next = m;
2611 m = mh;
2612 m->m_len = sizeof(*ip6);
2613 bcopy((caddr_t)ip6, mtod(m, caddr_t), sizeof(*ip6));
2614 }
2615 exthdrs->ip6e_ip6 = m;
2616 return 0;
2617 }
2618
2619 u_int32_t
2620 ip6_randomid(void)
2621 {
2622 return idgen32(&ip6_id_ctx);
2623 }
2624
2625 void
2626 ip6_randomid_init(void)
2627 {
2628 idgen32_init(&ip6_id_ctx);
2629 }
2630
2631 /*
2632 * Compute significant parts of the IPv6 checksum pseudo-header
2633 * for use in a delayed TCP/UDP checksum calculation.
2634 */
2635 static __inline u_int16_t __attribute__((__unused__))
2636 in6_cksum_phdr(const struct in6_addr *src, const struct in6_addr *dst,
2637 u_int32_t len, u_int32_t nxt)
2638 {
2639 u_int32_t sum = 0;
2640 const u_int16_t *w;
2641
2642 w = (const u_int16_t *) src;
2643 sum += w[0];
2644 if (!IN6_IS_SCOPE_EMBED(src))
2645 sum += w[1];
2646 sum += w[2]; sum += w[3]; sum += w[4]; sum += w[5];
2647 sum += w[6]; sum += w[7];
2648
2649 w = (const u_int16_t *) dst;
2650 sum += w[0];
2651 if (!IN6_IS_SCOPE_EMBED(dst))
2652 sum += w[1];
2653 sum += w[2]; sum += w[3]; sum += w[4]; sum += w[5];
2654 sum += w[6]; sum += w[7];
2655
2656 sum += (u_int16_t)(len >> 16) + (u_int16_t)(len /*& 0xffff*/);
2657
2658 sum += (u_int16_t)(nxt >> 16) + (u_int16_t)(nxt /*& 0xffff*/);
2659
2660 sum = (u_int16_t)(sum >> 16) + (u_int16_t)(sum /*& 0xffff*/);
2661
2662 if (sum > 0xffff)
2663 sum -= 0xffff;
2664
2665 return (sum);
2666 }
2667
2668 /*
2669 * Process a delayed payload checksum calculation.
2670 */
2671 void
2672 in6_delayed_cksum(struct mbuf *m, u_int8_t nxt)
2673 {
2674 int nxtp, offset;
2675 u_int16_t csum;
2676
2677 offset = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxtp);
2678 if (offset <= 0 || nxtp != nxt)
2679 /* If the desired next protocol isn't found, punt. */
2680 return;
2681 csum = (u_int16_t)(in6_cksum(m, 0, offset, m->m_pkthdr.len - offset));
2682
2683 switch (nxt) {
2684 case IPPROTO_TCP:
2685 offset += offsetof(struct tcphdr, th_sum);
2686 break;
2687
2688 case IPPROTO_UDP:
2689 offset += offsetof(struct udphdr, uh_sum);
2690 if (csum == 0)
2691 csum = 0xffff;
2692 break;
2693
2694 case IPPROTO_ICMPV6:
2695 offset += offsetof(struct icmp6_hdr, icmp6_cksum);
2696 break;
2697 }
2698
2699 if ((offset + sizeof(u_int16_t)) > m->m_len)
2700 m_copyback(m, offset, sizeof(csum), &csum, M_NOWAIT);
2701 else
2702 *(u_int16_t *)(mtod(m, caddr_t) + offset) = csum;
2703 }
2704
2705 void
2706 in6_proto_cksum_out(struct mbuf *m, struct ifnet *ifp)
2707 {
2708 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
2709
2710 /* some hw and in6_delayed_cksum need the pseudo header cksum */
2711 if (m->m_pkthdr.csum_flags &
2712 (M_TCP_CSUM_OUT|M_UDP_CSUM_OUT|M_ICMP_CSUM_OUT)) {
2713 int nxt, offset;
2714 u_int16_t csum;
2715
2716 offset = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt);
2717 csum = in6_cksum_phdr(&ip6->ip6_src, &ip6->ip6_dst,
2718 htonl(m->m_pkthdr.len - offset), htonl(nxt));
2719 if (nxt == IPPROTO_TCP)
2720 offset += offsetof(struct tcphdr, th_sum);
2721 else if (nxt == IPPROTO_UDP)
2722 offset += offsetof(struct udphdr, uh_sum);
2723 else if (nxt == IPPROTO_ICMPV6)
2724 offset += offsetof(struct icmp6_hdr, icmp6_cksum);
2725 if ((offset + sizeof(u_int16_t)) > m->m_len)
2726 m_copyback(m, offset, sizeof(csum), &csum, M_NOWAIT);
2727 else
2728 *(u_int16_t *)(mtod(m, caddr_t) + offset) = csum;
2729 }
2730
2731 if (m->m_pkthdr.csum_flags & M_TCP_CSUM_OUT) {
2732 if (!ifp || !(ifp->if_capabilities & IFCAP_CSUM_TCPv6) ||
2733 ip6->ip6_nxt != IPPROTO_TCP ||
2734 ifp->if_bridgeidx != 0) {
2735 tcpstat_inc(tcps_outswcsum);
2736 in6_delayed_cksum(m, IPPROTO_TCP);
2737 m->m_pkthdr.csum_flags &= ~M_TCP_CSUM_OUT; /* Clear */
2738 }
2739 } else if (m->m_pkthdr.csum_flags & M_UDP_CSUM_OUT) {
2740 if (!ifp || !(ifp->if_capabilities & IFCAP_CSUM_UDPv6) ||
2741 ip6->ip6_nxt != IPPROTO_UDP ||
2742 ifp->if_bridgeidx != 0) {
2743 udpstat_inc(udps_outswcsum);
2744 in6_delayed_cksum(m, IPPROTO_UDP);
2745 m->m_pkthdr.csum_flags &= ~M_UDP_CSUM_OUT; /* Clear */
2746 }
2747 } else if (m->m_pkthdr.csum_flags & M_ICMP_CSUM_OUT) {
2748 in6_delayed_cksum(m, IPPROTO_ICMPV6);
2749 m->m_pkthdr.csum_flags &= ~M_ICMP_CSUM_OUT; /* Clear */
2750 }
2751 }
2752
2753 #ifdef IPSEC
2754 int
2755 ip6_output_ipsec_lookup(struct mbuf *m, struct inpcb *inp, struct tdb **tdbout)
2756 {
2757 struct tdb *tdb;
2758 struct m_tag *mtag;
2759 struct tdb_ident *tdbi;
2760 int error;
2761
2762 /*
2763 * Check if there was an outgoing SA bound to the flow
2764 * from a transport protocol.
2765 */
2766
2767 /* Do we have any pending SAs to apply ? */
2768 error = ipsp_spd_lookup(m, AF_INET6, sizeof(struct ip6_hdr),
2769 IPSP_DIRECTION_OUT, NULL, inp, &tdb, NULL);
2770 if (error || tdb == NULL) {
2771 *tdbout = NULL;
2772 return error;
2773 }
2774 /* Loop detection */
2775 for (mtag = m_tag_first(m); mtag != NULL; mtag = m_tag_next(m, mtag)) {
2776 if (mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_DONE)
2777 continue;
2778 tdbi = (struct tdb_ident *)(mtag + 1);
2779 if (tdbi->spi == tdb->tdb_spi &&
2780 tdbi->proto == tdb->tdb_sproto &&
2781 tdbi->rdomain == tdb->tdb_rdomain &&
2782 !memcmp(&tdbi->dst, &tdb->tdb_dst,
2783 sizeof(union sockaddr_union))) {
2784 /* no IPsec needed */
2785 tdb_unref(tdb);
2786 *tdbout = NULL;
2787 return 0;
2788 }
2789 }
2790 *tdbout = tdb;
2791 return 0;
2792 }
2793
2794 int
2795 ip6_output_ipsec_pmtu_update(struct tdb *tdb, struct route_in6 *ro,
2796 struct in6_addr *dst, int ifidx, int rtableid, int transportmode)
2797 {
2798 struct rtentry *rt = NULL;
2799 int rt_mtucloned = 0;
2800
2801 /* Find a host route to store the mtu in */
2802 if (ro != NULL)
2803 rt = ro->ro_rt;
2804 /* but don't add a PMTU route for transport mode SAs */
2805 if (transportmode)
2806 rt = NULL;
2807 else if (rt == NULL || (rt->rt_flags & RTF_HOST) == 0) {
2808 struct sockaddr_in6 sin6;
2809 int error;
2810
2811 memset(&sin6, 0, sizeof(sin6));
2812 sin6.sin6_family = AF_INET6;
2813 sin6.sin6_len = sizeof(sin6);
2814 sin6.sin6_addr = *dst;
2815 sin6.sin6_scope_id = in6_addr2scopeid(ifidx, dst);
2816 error = in6_embedscope(dst, &sin6, NULL);
2817 if (error) {
2818 /* should be impossible */
2819 return error;
2820 }
2821 rt = icmp6_mtudisc_clone(&sin6, rtableid, 1);
2822 rt_mtucloned = 1;
2823 }
2824 DPRINTF("spi %08x mtu %d rt %p cloned %d",
2825 ntohl(tdb->tdb_spi), tdb->tdb_mtu, rt, rt_mtucloned);
2826 if (rt != NULL) {
2827 rt->rt_mtu = tdb->tdb_mtu;
2828 if (ro != NULL && ro->ro_rt != NULL) {
2829 rtfree(ro->ro_rt);
2830 ro->ro_rt = rtalloc(sin6tosa(&ro->ro_dst), RT_RESOLVE,
2831 rtableid);
2832 }
2833 if (rt_mtucloned)
2834 rtfree(rt);
2835 }
2836 return 0;
2837 }
2838
2839 int
2840 ip6_output_ipsec_send(struct tdb *tdb, struct mbuf *m, struct route_in6 *ro,
2841 int tunalready, int fwd)
2842 {
2843 #if NPF > 0
2844 struct ifnet *encif;
2845 #endif
2846 struct ip6_hdr *ip6;
2847 struct in6_addr dst;
2848 int error, ifidx, rtableid;
2849
2850 #if NPF > 0
2851 /*
2852 * Packet filter
2853 */
2854 if ((encif = enc_getif(tdb->tdb_rdomain, tdb->tdb_tap)) == NULL ||
2855 pf_test(AF_INET6, fwd ? PF_FWD : PF_OUT, encif, &m) != PF_PASS) {
2856 m_freem(m);
2857 return EACCES;
2858 }
2859 if (m == NULL)
2860 return 0;
2861 /*
2862 * PF_TAG_REROUTE handling or not...
2863 * Packet is entering IPsec so the routing is
2864 * already overruled by the IPsec policy.
2865 * Until now the change was not reconsidered.
2866 * What's the behaviour?
2867 */
2868 in6_proto_cksum_out(m, encif);
2869 #endif
2870
2871 /* Check if we are allowed to fragment */
2872 ip6 = mtod(m, struct ip6_hdr *);
2873 dst = ip6->ip6_dst;
2874 ifidx = m->m_pkthdr.ph_ifidx;
2875 rtableid = m->m_pkthdr.ph_rtableid;
2876 if (ip_mtudisc && tdb->tdb_mtu &&
2877 sizeof(struct ip6_hdr) + ntohs(ip6->ip6_plen) > tdb->tdb_mtu &&
2878 tdb->tdb_mtutimeout > gettime()) {
2879 int transportmode;
2880
2881 transportmode = (tdb->tdb_dst.sa.sa_family == AF_INET6) &&
2882 (IN6_ARE_ADDR_EQUAL(&tdb->tdb_dst.sin6.sin6_addr, &dst));
2883 error = ip6_output_ipsec_pmtu_update(tdb, ro, &dst, ifidx,
2884 rtableid, transportmode);
2885 if (error) {
2886 ipsecstat_inc(ipsec_odrops);
2887 tdbstat_inc(tdb, tdb_odrops);
2888 m_freem(m);
2889 return error;
2890 }
2891 ipsec_adjust_mtu(m, tdb->tdb_mtu);
2892 m_freem(m);
2893 return EMSGSIZE;
2894 }
2895 /* propagate don't fragment for v6-over-v6 */
2896 if (ip_mtudisc)
2897 SET(m->m_pkthdr.csum_flags, M_IPV6_DF_OUT);
2898
2899 /*
2900 * Clear these -- they'll be set in the recursive invocation
2901 * as needed.
2902 */
2903 m->m_flags &= ~(M_BCAST | M_MCAST);
2904
2905 /* Callee frees mbuf */
2906 KERNEL_LOCK();
2907 error = ipsp_process_packet(m, tdb, AF_INET6, tunalready);
2908 KERNEL_UNLOCK();
2909 if (error) {
2910 ipsecstat_inc(ipsec_odrops);
2911 tdbstat_inc(tdb, tdb_odrops);
2912 }
2913 if (ip_mtudisc && error == EMSGSIZE)
2914 ip6_output_ipsec_pmtu_update(tdb, ro, &dst, ifidx, rtableid, 0);
2915 return error;
2916 }
2917 #endif /* IPSEC */
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