1 /*-
2 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
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 * 3. Neither the name of the project nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 * $KAME: ip6_output.c,v 1.279 2002/01/26 06:12:30 jinmei Exp $
30 */
31
32 /*-
33 * Copyright (c) 1982, 1986, 1988, 1990, 1993
34 * The Regents of the University of California. All rights reserved.
35 *
36 * Redistribution and use in source and binary forms, with or without
37 * modification, are permitted provided that the following conditions
38 * are met:
39 * 1. Redistributions of source code must retain the above copyright
40 * notice, this list of conditions and the following disclaimer.
41 * 2. Redistributions in binary form must reproduce the above copyright
42 * notice, this list of conditions and the following disclaimer in the
43 * documentation and/or other materials provided with the distribution.
44 * 4. Neither the name of the University nor the names of its contributors
45 * may be used to endorse or promote products derived from this software
46 * without specific prior written permission.
47 *
48 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
49 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
50 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
51 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
52 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
53 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
54 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
55 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
56 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
57 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
58 * SUCH DAMAGE.
59 *
60 * @(#)ip_output.c 8.3 (Berkeley) 1/21/94
61 */
62
63 #include <sys/cdefs.h>
64 __FBSDID("$FreeBSD$");
65
66 #include "opt_inet.h"
67 #include "opt_inet6.h"
68 #include "opt_ipfw.h"
69 #include "opt_ipsec.h"
70 #include "opt_sctp.h"
71 #include "opt_route.h"
72
73 #include <sys/param.h>
74 #include <sys/kernel.h>
75 #include <sys/malloc.h>
76 #include <sys/mbuf.h>
77 #include <sys/errno.h>
78 #include <sys/priv.h>
79 #include <sys/proc.h>
80 #include <sys/protosw.h>
81 #include <sys/socket.h>
82 #include <sys/socketvar.h>
83 #include <sys/syslog.h>
84 #include <sys/ucred.h>
85
86 #include <machine/in_cksum.h>
87
88 #include <net/if.h>
89 #include <net/netisr.h>
90 #include <net/route.h>
91 #include <net/pfil.h>
92 #include <net/vnet.h>
93
94 #include <netinet/in.h>
95 #include <netinet/in_var.h>
96 #include <netinet/ip_var.h>
97 #include <netinet6/in6_var.h>
98 #include <netinet/ip6.h>
99 #include <netinet/icmp6.h>
100 #include <netinet6/ip6_var.h>
101 #include <netinet/in_pcb.h>
102 #include <netinet/tcp_var.h>
103 #include <netinet6/nd6.h>
104
105 #ifdef IPSEC
106 #include <netipsec/ipsec.h>
107 #include <netipsec/ipsec6.h>
108 #include <netipsec/key.h>
109 #include <netinet6/ip6_ipsec.h>
110 #endif /* IPSEC */
111 #ifdef SCTP
112 #include <netinet/sctp.h>
113 #include <netinet/sctp_crc32.h>
114 #endif
115
116 #include <netinet6/ip6protosw.h>
117 #include <netinet6/scope6_var.h>
118
119 #ifdef FLOWTABLE
120 #include <net/flowtable.h>
121 #endif
122
123 extern int in6_mcast_loop;
124
125 struct ip6_exthdrs {
126 struct mbuf *ip6e_ip6;
127 struct mbuf *ip6e_hbh;
128 struct mbuf *ip6e_dest1;
129 struct mbuf *ip6e_rthdr;
130 struct mbuf *ip6e_dest2;
131 };
132
133 static int ip6_pcbopt(int, u_char *, int, struct ip6_pktopts **,
134 struct ucred *, int);
135 static int ip6_pcbopts(struct ip6_pktopts **, struct mbuf *,
136 struct socket *, struct sockopt *);
137 static int ip6_getpcbopt(struct ip6_pktopts *, int, struct sockopt *);
138 static int ip6_setpktopt(int, u_char *, int, struct ip6_pktopts *,
139 struct ucred *, int, int, int);
140
141 static int ip6_copyexthdr(struct mbuf **, caddr_t, int);
142 static int ip6_insertfraghdr(struct mbuf *, struct mbuf *, int,
143 struct ip6_frag **);
144 static int ip6_insert_jumboopt(struct ip6_exthdrs *, u_int32_t);
145 static int ip6_splithdr(struct mbuf *, struct ip6_exthdrs *);
146 static int ip6_getpmtu(struct route_in6 *, struct route_in6 *,
147 struct ifnet *, struct in6_addr *, u_long *, int *, u_int);
148 static int copypktopts(struct ip6_pktopts *, struct ip6_pktopts *, int);
149
150
151 /*
152 * Make an extension header from option data. hp is the source, and
153 * mp is the destination.
154 */
155 #define MAKE_EXTHDR(hp, mp) \
156 do { \
157 if (hp) { \
158 struct ip6_ext *eh = (struct ip6_ext *)(hp); \
159 error = ip6_copyexthdr((mp), (caddr_t)(hp), \
160 ((eh)->ip6e_len + 1) << 3); \
161 if (error) \
162 goto freehdrs; \
163 } \
164 } while (/*CONSTCOND*/ 0)
165
166 /*
167 * Form a chain of extension headers.
168 * m is the extension header mbuf
169 * mp is the previous mbuf in the chain
170 * p is the next header
171 * i is the type of option.
172 */
173 #define MAKE_CHAIN(m, mp, p, i)\
174 do {\
175 if (m) {\
176 if (!hdrsplit) \
177 panic("assumption failed: hdr not split"); \
178 *mtod((m), u_char *) = *(p);\
179 *(p) = (i);\
180 p = mtod((m), u_char *);\
181 (m)->m_next = (mp)->m_next;\
182 (mp)->m_next = (m);\
183 (mp) = (m);\
184 }\
185 } while (/*CONSTCOND*/ 0)
186
187 void
in6_delayed_cksum(struct mbuf * m,uint32_t plen,u_short offset)188 in6_delayed_cksum(struct mbuf *m, uint32_t plen, u_short offset)
189 {
190 u_short csum;
191
192 csum = in_cksum_skip(m, offset + plen, offset);
193 if (m->m_pkthdr.csum_flags & CSUM_UDP_IPV6 && csum == 0)
194 csum = 0xffff;
195 offset += m->m_pkthdr.csum_data; /* checksum offset */
196
197 if (offset + sizeof(u_short) > m->m_len) {
198 printf("%s: delayed m_pullup, m->len: %d plen %u off %u "
199 "csum_flags=%b\n", __func__, m->m_len, plen, offset,
200 (int)m->m_pkthdr.csum_flags, CSUM_BITS);
201 /*
202 * XXX this should not happen, but if it does, the correct
203 * behavior may be to insert the checksum in the appropriate
204 * next mbuf in the chain.
205 */
206 return;
207 }
208 *(u_short *)(m->m_data + offset) = csum;
209 }
210
211 /*
212 * IP6 output. The packet in mbuf chain m contains a skeletal IP6
213 * header (with pri, len, nxt, hlim, src, dst).
214 * This function may modify ver and hlim only.
215 * The mbuf chain containing the packet will be freed.
216 * The mbuf opt, if present, will not be freed.
217 * If route_in6 ro is present and has ro_rt initialized, route lookup would be
218 * skipped and ro->ro_rt would be used. If ro is present but ro->ro_rt is NULL,
219 * then result of route lookup is stored in ro->ro_rt.
220 *
221 * type of "mtu": rt_mtu is u_long, ifnet.ifr_mtu is int, and
222 * nd_ifinfo.linkmtu is u_int32_t. so we use u_long to hold largest one,
223 * which is rt_mtu.
224 *
225 * ifpp - XXX: just for statistics
226 */
227 int
ip6_output(struct mbuf * m0,struct ip6_pktopts * opt,struct route_in6 * ro,int flags,struct ip6_moptions * im6o,struct ifnet ** ifpp,struct inpcb * inp)228 ip6_output(struct mbuf *m0, struct ip6_pktopts *opt,
229 struct route_in6 *ro, int flags, struct ip6_moptions *im6o,
230 struct ifnet **ifpp, struct inpcb *inp)
231 {
232 struct ip6_hdr *ip6, *mhip6;
233 struct ifnet *ifp, *origifp;
234 struct mbuf *m = m0;
235 struct mbuf *mprev = NULL;
236 int hlen, tlen, len, off;
237 struct route_in6 ip6route;
238 struct rtentry *rt = NULL;
239 struct sockaddr_in6 *dst, src_sa, dst_sa;
240 struct in6_addr odst;
241 int error = 0;
242 struct in6_ifaddr *ia = NULL;
243 u_long mtu;
244 int alwaysfrag, dontfrag;
245 u_int32_t optlen = 0, plen = 0, unfragpartlen = 0;
246 struct ip6_exthdrs exthdrs;
247 struct in6_addr finaldst, src0, dst0;
248 u_int32_t zone;
249 struct route_in6 *ro_pmtu = NULL;
250 int hdrsplit = 0;
251 int sw_csum, tso;
252 struct m_tag *fwd_tag = NULL;
253
254 ip6 = mtod(m, struct ip6_hdr *);
255 if (ip6 == NULL) {
256 printf ("ip6 is NULL");
257 goto bad;
258 }
259
260 if (inp != NULL)
261 M_SETFIB(m, inp->inp_inc.inc_fibnum);
262
263 finaldst = ip6->ip6_dst;
264 bzero(&exthdrs, sizeof(exthdrs));
265 if (opt) {
266 /* Hop-by-Hop options header */
267 MAKE_EXTHDR(opt->ip6po_hbh, &exthdrs.ip6e_hbh);
268 /* Destination options header(1st part) */
269 if (opt->ip6po_rthdr) {
270 /*
271 * Destination options header(1st part)
272 * This only makes sense with a routing header.
273 * See Section 9.2 of RFC 3542.
274 * Disabling this part just for MIP6 convenience is
275 * a bad idea. We need to think carefully about a
276 * way to make the advanced API coexist with MIP6
277 * options, which might automatically be inserted in
278 * the kernel.
279 */
280 MAKE_EXTHDR(opt->ip6po_dest1, &exthdrs.ip6e_dest1);
281 }
282 /* Routing header */
283 MAKE_EXTHDR(opt->ip6po_rthdr, &exthdrs.ip6e_rthdr);
284 /* Destination options header(2nd part) */
285 MAKE_EXTHDR(opt->ip6po_dest2, &exthdrs.ip6e_dest2);
286 }
287
288 #ifdef IPSEC
289 /*
290 * IPSec checking which handles several cases.
291 * FAST IPSEC: We re-injected the packet.
292 */
293 switch(ip6_ipsec_output(&m, inp, &flags, &error, &ifp))
294 {
295 case 1: /* Bad packet */
296 goto freehdrs;
297 case -1: /* IPSec done */
298 goto done;
299 case 0: /* No IPSec */
300 default:
301 break;
302 }
303 #endif /* IPSEC */
304
305 /*
306 * Calculate the total length of the extension header chain.
307 * Keep the length of the unfragmentable part for fragmentation.
308 */
309 optlen = 0;
310 if (exthdrs.ip6e_hbh)
311 optlen += exthdrs.ip6e_hbh->m_len;
312 if (exthdrs.ip6e_dest1)
313 optlen += exthdrs.ip6e_dest1->m_len;
314 if (exthdrs.ip6e_rthdr)
315 optlen += exthdrs.ip6e_rthdr->m_len;
316 unfragpartlen = optlen + sizeof(struct ip6_hdr);
317
318 /* NOTE: we don't add AH/ESP length here (done in ip6_ipsec_output) */
319 if (exthdrs.ip6e_dest2)
320 optlen += exthdrs.ip6e_dest2->m_len;
321
322 /*
323 * If there is at least one extension header,
324 * separate IP6 header from the payload.
325 */
326 if (optlen && !hdrsplit) {
327 if ((error = ip6_splithdr(m, &exthdrs)) != 0) {
328 m = NULL;
329 goto freehdrs;
330 }
331 m = exthdrs.ip6e_ip6;
332 hdrsplit++;
333 }
334
335 /* adjust pointer */
336 ip6 = mtod(m, struct ip6_hdr *);
337
338 /* adjust mbuf packet header length */
339 m->m_pkthdr.len += optlen;
340 plen = m->m_pkthdr.len - sizeof(*ip6);
341
342 /* If this is a jumbo payload, insert a jumbo payload option. */
343 if (plen > IPV6_MAXPACKET) {
344 if (!hdrsplit) {
345 if ((error = ip6_splithdr(m, &exthdrs)) != 0) {
346 m = NULL;
347 goto freehdrs;
348 }
349 m = exthdrs.ip6e_ip6;
350 hdrsplit++;
351 }
352 /* adjust pointer */
353 ip6 = mtod(m, struct ip6_hdr *);
354 if ((error = ip6_insert_jumboopt(&exthdrs, plen)) != 0)
355 goto freehdrs;
356 ip6->ip6_plen = 0;
357 } else
358 ip6->ip6_plen = htons(plen);
359
360 /*
361 * Concatenate headers and fill in next header fields.
362 * Here we have, on "m"
363 * IPv6 payload
364 * and we insert headers accordingly. Finally, we should be getting:
365 * IPv6 hbh dest1 rthdr ah* [esp* dest2 payload]
366 *
367 * during the header composing process, "m" points to IPv6 header.
368 * "mprev" points to an extension header prior to esp.
369 */
370 u_char *nexthdrp = &ip6->ip6_nxt;
371 mprev = m;
372
373 /*
374 * we treat dest2 specially. this makes IPsec processing
375 * much easier. the goal here is to make mprev point the
376 * mbuf prior to dest2.
377 *
378 * result: IPv6 dest2 payload
379 * m and mprev will point to IPv6 header.
380 */
381 if (exthdrs.ip6e_dest2) {
382 if (!hdrsplit)
383 panic("assumption failed: hdr not split");
384 exthdrs.ip6e_dest2->m_next = m->m_next;
385 m->m_next = exthdrs.ip6e_dest2;
386 *mtod(exthdrs.ip6e_dest2, u_char *) = ip6->ip6_nxt;
387 ip6->ip6_nxt = IPPROTO_DSTOPTS;
388 }
389
390 /*
391 * result: IPv6 hbh dest1 rthdr dest2 payload
392 * m will point to IPv6 header. mprev will point to the
393 * extension header prior to dest2 (rthdr in the above case).
394 */
395 MAKE_CHAIN(exthdrs.ip6e_hbh, mprev, nexthdrp, IPPROTO_HOPOPTS);
396 MAKE_CHAIN(exthdrs.ip6e_dest1, mprev, nexthdrp,
397 IPPROTO_DSTOPTS);
398 MAKE_CHAIN(exthdrs.ip6e_rthdr, mprev, nexthdrp,
399 IPPROTO_ROUTING);
400
401 /*
402 * If there is a routing header, discard the packet.
403 */
404 if (exthdrs.ip6e_rthdr) {
405 error = EINVAL;
406 goto bad;
407 }
408
409 /* Source address validation */
410 if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) &&
411 (flags & IPV6_UNSPECSRC) == 0) {
412 error = EOPNOTSUPP;
413 IP6STAT_INC(ip6s_badscope);
414 goto bad;
415 }
416 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src)) {
417 error = EOPNOTSUPP;
418 IP6STAT_INC(ip6s_badscope);
419 goto bad;
420 }
421
422 IP6STAT_INC(ip6s_localout);
423
424 /*
425 * Route packet.
426 */
427 if (ro == 0) {
428 ro = &ip6route;
429 bzero((caddr_t)ro, sizeof(*ro));
430 }
431 ro_pmtu = ro;
432 if (opt && opt->ip6po_rthdr)
433 ro = &opt->ip6po_route;
434 dst = (struct sockaddr_in6 *)&ro->ro_dst;
435 #ifdef FLOWTABLE
436 if (ro->ro_rt == NULL)
437 (void )flowtable_lookup(AF_INET6, m, (struct route *)ro);
438 #endif
439 again:
440 /*
441 * if specified, try to fill in the traffic class field.
442 * do not override if a non-zero value is already set.
443 * we check the diffserv field and the ecn field separately.
444 */
445 if (opt && opt->ip6po_tclass >= 0) {
446 int mask = 0;
447
448 if ((ip6->ip6_flow & htonl(0xfc << 20)) == 0)
449 mask |= 0xfc;
450 if ((ip6->ip6_flow & htonl(0x03 << 20)) == 0)
451 mask |= 0x03;
452 if (mask != 0)
453 ip6->ip6_flow |= htonl((opt->ip6po_tclass & mask) << 20);
454 }
455
456 /* fill in or override the hop limit field, if necessary. */
457 if (opt && opt->ip6po_hlim != -1)
458 ip6->ip6_hlim = opt->ip6po_hlim & 0xff;
459 else if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
460 if (im6o != NULL)
461 ip6->ip6_hlim = im6o->im6o_multicast_hlim;
462 else
463 ip6->ip6_hlim = V_ip6_defmcasthlim;
464 }
465
466 /* adjust pointer */
467 ip6 = mtod(m, struct ip6_hdr *);
468
469 if (ro->ro_rt && fwd_tag == NULL) {
470 rt = ro->ro_rt;
471 ifp = ro->ro_rt->rt_ifp;
472 } else {
473 if (fwd_tag == NULL) {
474 bzero(&dst_sa, sizeof(dst_sa));
475 dst_sa.sin6_family = AF_INET6;
476 dst_sa.sin6_len = sizeof(dst_sa);
477 dst_sa.sin6_addr = ip6->ip6_dst;
478 }
479 error = in6_selectroute_fib(&dst_sa, opt, im6o, ro, &ifp,
480 &rt, inp ? inp->inp_inc.inc_fibnum : M_GETFIB(m));
481 if (error != 0) {
482 if (ifp != NULL)
483 in6_ifstat_inc(ifp, ifs6_out_discard);
484 goto bad;
485 }
486 }
487 if (rt == NULL) {
488 /*
489 * If in6_selectroute() does not return a route entry,
490 * dst may not have been updated.
491 */
492 *dst = dst_sa; /* XXX */
493 }
494
495 /*
496 * then rt (for unicast) and ifp must be non-NULL valid values.
497 */
498 if ((flags & IPV6_FORWARDING) == 0) {
499 /* XXX: the FORWARDING flag can be set for mrouting. */
500 in6_ifstat_inc(ifp, ifs6_out_request);
501 }
502 if (rt != NULL) {
503 ia = (struct in6_ifaddr *)(rt->rt_ifa);
504 counter_u64_add(rt->rt_pksent, 1);
505 }
506
507
508 /*
509 * The outgoing interface must be in the zone of source and
510 * destination addresses.
511 */
512 origifp = ifp;
513
514 src0 = ip6->ip6_src;
515 if (in6_setscope(&src0, origifp, &zone))
516 goto badscope;
517 bzero(&src_sa, sizeof(src_sa));
518 src_sa.sin6_family = AF_INET6;
519 src_sa.sin6_len = sizeof(src_sa);
520 src_sa.sin6_addr = ip6->ip6_src;
521 if (sa6_recoverscope(&src_sa) || zone != src_sa.sin6_scope_id)
522 goto badscope;
523
524 dst0 = ip6->ip6_dst;
525 if (in6_setscope(&dst0, origifp, &zone))
526 goto badscope;
527 /* re-initialize to be sure */
528 bzero(&dst_sa, sizeof(dst_sa));
529 dst_sa.sin6_family = AF_INET6;
530 dst_sa.sin6_len = sizeof(dst_sa);
531 dst_sa.sin6_addr = ip6->ip6_dst;
532 if (sa6_recoverscope(&dst_sa) || zone != dst_sa.sin6_scope_id) {
533 goto badscope;
534 }
535
536 /* We should use ia_ifp to support the case of
537 * sending packets to an address of our own.
538 */
539 if (ia != NULL && ia->ia_ifp)
540 ifp = ia->ia_ifp;
541
542 /* scope check is done. */
543 goto routefound;
544
545 badscope:
546 IP6STAT_INC(ip6s_badscope);
547 in6_ifstat_inc(origifp, ifs6_out_discard);
548 if (error == 0)
549 error = EHOSTUNREACH; /* XXX */
550 goto bad;
551
552 routefound:
553 if (rt && !IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
554 if (opt && opt->ip6po_nextroute.ro_rt) {
555 /*
556 * The nexthop is explicitly specified by the
557 * application. We assume the next hop is an IPv6
558 * address.
559 */
560 dst = (struct sockaddr_in6 *)opt->ip6po_nexthop;
561 }
562 else if ((rt->rt_flags & RTF_GATEWAY))
563 dst = (struct sockaddr_in6 *)rt->rt_gateway;
564 }
565
566 if (!IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
567 m->m_flags &= ~(M_BCAST | M_MCAST); /* just in case */
568 } else {
569 m->m_flags = (m->m_flags & ~M_BCAST) | M_MCAST;
570 in6_ifstat_inc(ifp, ifs6_out_mcast);
571 /*
572 * Confirm that the outgoing interface supports multicast.
573 */
574 if (!(ifp->if_flags & IFF_MULTICAST)) {
575 IP6STAT_INC(ip6s_noroute);
576 in6_ifstat_inc(ifp, ifs6_out_discard);
577 error = ENETUNREACH;
578 goto bad;
579 }
580 if ((im6o == NULL && in6_mcast_loop) ||
581 (im6o && im6o->im6o_multicast_loop)) {
582 /*
583 * Loop back multicast datagram if not expressly
584 * forbidden to do so, even if we have not joined
585 * the address; protocols will filter it later,
586 * thus deferring a hash lookup and lock acquisition
587 * at the expense of an m_copym().
588 */
589 ip6_mloopback(ifp, m, dst);
590 } else {
591 /*
592 * If we are acting as a multicast router, perform
593 * multicast forwarding as if the packet had just
594 * arrived on the interface to which we are about
595 * to send. The multicast forwarding function
596 * recursively calls this function, using the
597 * IPV6_FORWARDING flag to prevent infinite recursion.
598 *
599 * Multicasts that are looped back by ip6_mloopback(),
600 * above, will be forwarded by the ip6_input() routine,
601 * if necessary.
602 */
603 if (V_ip6_mrouter && (flags & IPV6_FORWARDING) == 0) {
604 /*
605 * XXX: ip6_mforward expects that rcvif is NULL
606 * when it is called from the originating path.
607 * However, it may not always be the case.
608 */
609 m->m_pkthdr.rcvif = NULL;
610 if (ip6_mforward(ip6, ifp, m) != 0) {
611 m_freem(m);
612 goto done;
613 }
614 }
615 }
616 /*
617 * Multicasts with a hoplimit of zero may be looped back,
618 * above, but must not be transmitted on a network.
619 * Also, multicasts addressed to the loopback interface
620 * are not sent -- the above call to ip6_mloopback() will
621 * loop back a copy if this host actually belongs to the
622 * destination group on the loopback interface.
623 */
624 if (ip6->ip6_hlim == 0 || (ifp->if_flags & IFF_LOOPBACK) ||
625 IN6_IS_ADDR_MC_INTFACELOCAL(&ip6->ip6_dst)) {
626 m_freem(m);
627 goto done;
628 }
629 }
630
631 /*
632 * Fill the outgoing inteface to tell the upper layer
633 * to increment per-interface statistics.
634 */
635 if (ifpp)
636 *ifpp = ifp;
637
638 /* Determine path MTU. */
639 if ((error = ip6_getpmtu(ro_pmtu, ro, ifp, &finaldst, &mtu,
640 &alwaysfrag, inp ? inp->inp_inc.inc_fibnum : M_GETFIB(m))) != 0)
641 goto bad;
642
643 /*
644 * The caller of this function may specify to use the minimum MTU
645 * in some cases.
646 * An advanced API option (IPV6_USE_MIN_MTU) can also override MTU
647 * setting. The logic is a bit complicated; by default, unicast
648 * packets will follow path MTU while multicast packets will be sent at
649 * the minimum MTU. If IP6PO_MINMTU_ALL is specified, all packets
650 * including unicast ones will be sent at the minimum MTU. Multicast
651 * packets will always be sent at the minimum MTU unless
652 * IP6PO_MINMTU_DISABLE is explicitly specified.
653 * See RFC 3542 for more details.
654 */
655 if (mtu > IPV6_MMTU) {
656 if ((flags & IPV6_MINMTU))
657 mtu = IPV6_MMTU;
658 else if (opt && opt->ip6po_minmtu == IP6PO_MINMTU_ALL)
659 mtu = IPV6_MMTU;
660 else if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) &&
661 (opt == NULL ||
662 opt->ip6po_minmtu != IP6PO_MINMTU_DISABLE)) {
663 mtu = IPV6_MMTU;
664 }
665 }
666
667 /*
668 * clear embedded scope identifiers if necessary.
669 * in6_clearscope will touch the addresses only when necessary.
670 */
671 in6_clearscope(&ip6->ip6_src);
672 in6_clearscope(&ip6->ip6_dst);
673
674 /*
675 * If the outgoing packet contains a hop-by-hop options header,
676 * it must be examined and processed even by the source node.
677 * (RFC 2460, section 4.)
678 */
679 if (exthdrs.ip6e_hbh) {
680 struct ip6_hbh *hbh = mtod(exthdrs.ip6e_hbh, struct ip6_hbh *);
681 u_int32_t dummy; /* XXX unused */
682 u_int32_t plen = 0; /* XXX: ip6_process will check the value */
683
684 #ifdef DIAGNOSTIC
685 if ((hbh->ip6h_len + 1) << 3 > exthdrs.ip6e_hbh->m_len)
686 panic("ip6e_hbh is not contiguous");
687 #endif
688 /*
689 * XXX: if we have to send an ICMPv6 error to the sender,
690 * we need the M_LOOP flag since icmp6_error() expects
691 * the IPv6 and the hop-by-hop options header are
692 * contiguous unless the flag is set.
693 */
694 m->m_flags |= M_LOOP;
695 m->m_pkthdr.rcvif = ifp;
696 if (ip6_process_hopopts(m, (u_int8_t *)(hbh + 1),
697 ((hbh->ip6h_len + 1) << 3) - sizeof(struct ip6_hbh),
698 &dummy, &plen) < 0) {
699 /* m was already freed at this point */
700 error = EINVAL;/* better error? */
701 goto done;
702 }
703 m->m_flags &= ~M_LOOP; /* XXX */
704 m->m_pkthdr.rcvif = NULL;
705 }
706
707 /* Jump over all PFIL processing if hooks are not active. */
708 if (!PFIL_HOOKED(&V_inet6_pfil_hook))
709 goto passout;
710
711 odst = ip6->ip6_dst;
712 /* Run through list of hooks for output packets. */
713 error = pfil_run_hooks(&V_inet6_pfil_hook, &m, ifp, PFIL_OUT, inp);
714 if (error != 0 || m == NULL)
715 goto done;
716 ip6 = mtod(m, struct ip6_hdr *);
717
718 /* See if destination IP address was changed by packet filter. */
719 if (!IN6_ARE_ADDR_EQUAL(&odst, &ip6->ip6_dst)) {
720 m->m_flags |= M_SKIP_FIREWALL;
721 /* If destination is now ourself drop to ip6_input(). */
722 if (in6_localip(&ip6->ip6_dst)) {
723 m->m_flags |= M_FASTFWD_OURS;
724 if (m->m_pkthdr.rcvif == NULL)
725 m->m_pkthdr.rcvif = V_loif;
726 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
727 m->m_pkthdr.csum_flags |=
728 CSUM_DATA_VALID_IPV6 | CSUM_PSEUDO_HDR;
729 m->m_pkthdr.csum_data = 0xffff;
730 }
731 #ifdef SCTP
732 if (m->m_pkthdr.csum_flags & CSUM_SCTP_IPV6)
733 m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
734 #endif
735 error = netisr_queue(NETISR_IPV6, m);
736 goto done;
737 } else
738 goto again; /* Redo the routing table lookup. */
739 }
740
741 /* See if local, if yes, send it to netisr. */
742 if (m->m_flags & M_FASTFWD_OURS) {
743 if (m->m_pkthdr.rcvif == NULL)
744 m->m_pkthdr.rcvif = V_loif;
745 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
746 m->m_pkthdr.csum_flags |=
747 CSUM_DATA_VALID_IPV6 | CSUM_PSEUDO_HDR;
748 m->m_pkthdr.csum_data = 0xffff;
749 }
750 #ifdef SCTP
751 if (m->m_pkthdr.csum_flags & CSUM_SCTP_IPV6)
752 m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
753 #endif
754 error = netisr_queue(NETISR_IPV6, m);
755 goto done;
756 }
757 /* Or forward to some other address? */
758 if ((m->m_flags & M_IP6_NEXTHOP) &&
759 (fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL) {
760 dst = (struct sockaddr_in6 *)&ro->ro_dst;
761 bcopy((fwd_tag+1), &dst_sa, sizeof(struct sockaddr_in6));
762 m->m_flags |= M_SKIP_FIREWALL;
763 m->m_flags &= ~M_IP6_NEXTHOP;
764 m_tag_delete(m, fwd_tag);
765 goto again;
766 }
767
768 passout:
769 /*
770 * Send the packet to the outgoing interface.
771 * If necessary, do IPv6 fragmentation before sending.
772 *
773 * the logic here is rather complex:
774 * 1: normal case (dontfrag == 0, alwaysfrag == 0)
775 * 1-a: send as is if tlen <= path mtu
776 * 1-b: fragment if tlen > path mtu
777 *
778 * 2: if user asks us not to fragment (dontfrag == 1)
779 * 2-a: send as is if tlen <= interface mtu
780 * 2-b: error if tlen > interface mtu
781 *
782 * 3: if we always need to attach fragment header (alwaysfrag == 1)
783 * always fragment
784 *
785 * 4: if dontfrag == 1 && alwaysfrag == 1
786 * error, as we cannot handle this conflicting request
787 */
788 sw_csum = m->m_pkthdr.csum_flags;
789 if (!hdrsplit) {
790 tso = ((sw_csum & ifp->if_hwassist & CSUM_TSO) != 0) ? 1 : 0;
791 sw_csum &= ~ifp->if_hwassist;
792 } else
793 tso = 0;
794 /*
795 * If we added extension headers, we will not do TSO and calculate the
796 * checksums ourselves for now.
797 * XXX-BZ Need a framework to know when the NIC can handle it, even
798 * with ext. hdrs.
799 */
800 if (sw_csum & CSUM_DELAY_DATA_IPV6) {
801 sw_csum &= ~CSUM_DELAY_DATA_IPV6;
802 in6_delayed_cksum(m, plen, sizeof(struct ip6_hdr));
803 }
804 #ifdef SCTP
805 if (sw_csum & CSUM_SCTP_IPV6) {
806 sw_csum &= ~CSUM_SCTP_IPV6;
807 sctp_delayed_cksum(m, sizeof(struct ip6_hdr));
808 }
809 #endif
810 m->m_pkthdr.csum_flags &= ifp->if_hwassist;
811 tlen = m->m_pkthdr.len;
812
813 if ((opt && (opt->ip6po_flags & IP6PO_DONTFRAG)) || tso)
814 dontfrag = 1;
815 else
816 dontfrag = 0;
817 if (dontfrag && alwaysfrag) { /* case 4 */
818 /* conflicting request - can't transmit */
819 error = EMSGSIZE;
820 goto bad;
821 }
822 if (dontfrag && tlen > IN6_LINKMTU(ifp) && !tso) { /* case 2-b */
823 /*
824 * Even if the DONTFRAG option is specified, we cannot send the
825 * packet when the data length is larger than the MTU of the
826 * outgoing interface.
827 * Notify the error by sending IPV6_PATHMTU ancillary data if
828 * application wanted to know the MTU value. Also return an
829 * error code (this is not described in the API spec).
830 */
831 if (inp != NULL)
832 ip6_notify_pmtu(inp, &dst_sa, (u_int32_t)mtu);
833 error = EMSGSIZE;
834 goto bad;
835 }
836
837 /*
838 * transmit packet without fragmentation
839 */
840 if (dontfrag || (!alwaysfrag && tlen <= mtu)) { /* case 1-a and 2-a */
841 struct in6_ifaddr *ia6;
842
843 ip6 = mtod(m, struct ip6_hdr *);
844 ia6 = in6_ifawithifp(ifp, &ip6->ip6_src);
845 if (ia6) {
846 /* Record statistics for this interface address. */
847 ia6->ia_ifa.if_opackets++;
848 ia6->ia_ifa.if_obytes += m->m_pkthdr.len;
849 ifa_free(&ia6->ia_ifa);
850 }
851 error = nd6_output(ifp, origifp, m, dst, ro->ro_rt);
852 goto done;
853 }
854
855 /*
856 * try to fragment the packet. case 1-b and 3
857 */
858 if (mtu < IPV6_MMTU) {
859 /* path MTU cannot be less than IPV6_MMTU */
860 error = EMSGSIZE;
861 in6_ifstat_inc(ifp, ifs6_out_fragfail);
862 goto bad;
863 } else if (ip6->ip6_plen == 0) {
864 /* jumbo payload cannot be fragmented */
865 error = EMSGSIZE;
866 in6_ifstat_inc(ifp, ifs6_out_fragfail);
867 goto bad;
868 } else {
869 struct mbuf **mnext, *m_frgpart;
870 struct ip6_frag *ip6f;
871 u_int32_t id = htonl(ip6_randomid());
872 u_char nextproto;
873
874 int qslots = ifp->if_snd.ifq_maxlen - ifp->if_snd.ifq_len;
875
876 /*
877 * Too large for the destination or interface;
878 * fragment if possible.
879 * Must be able to put at least 8 bytes per fragment.
880 */
881 hlen = unfragpartlen;
882 if (mtu > IPV6_MAXPACKET)
883 mtu = IPV6_MAXPACKET;
884
885 len = (mtu - hlen - sizeof(struct ip6_frag)) & ~7;
886 if (len < 8) {
887 error = EMSGSIZE;
888 in6_ifstat_inc(ifp, ifs6_out_fragfail);
889 goto bad;
890 }
891
892 /*
893 * Verify that we have any chance at all of being able to queue
894 * the packet or packet fragments
895 */
896 if (qslots <= 0 || ((u_int)qslots * (mtu - hlen)
897 < tlen /* - hlen */)) {
898 error = ENOBUFS;
899 IP6STAT_INC(ip6s_odropped);
900 goto bad;
901 }
902
903
904 /*
905 * If the interface will not calculate checksums on
906 * fragmented packets, then do it here.
907 * XXX-BZ handle the hw offloading case. Need flags.
908 */
909 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
910 in6_delayed_cksum(m, plen, hlen);
911 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA_IPV6;
912 }
913 #ifdef SCTP
914 if (m->m_pkthdr.csum_flags & CSUM_SCTP_IPV6) {
915 sctp_delayed_cksum(m, hlen);
916 m->m_pkthdr.csum_flags &= ~CSUM_SCTP_IPV6;
917 }
918 #endif
919 mnext = &m->m_nextpkt;
920
921 /*
922 * Change the next header field of the last header in the
923 * unfragmentable part.
924 */
925 if (exthdrs.ip6e_rthdr) {
926 nextproto = *mtod(exthdrs.ip6e_rthdr, u_char *);
927 *mtod(exthdrs.ip6e_rthdr, u_char *) = IPPROTO_FRAGMENT;
928 } else if (exthdrs.ip6e_dest1) {
929 nextproto = *mtod(exthdrs.ip6e_dest1, u_char *);
930 *mtod(exthdrs.ip6e_dest1, u_char *) = IPPROTO_FRAGMENT;
931 } else if (exthdrs.ip6e_hbh) {
932 nextproto = *mtod(exthdrs.ip6e_hbh, u_char *);
933 *mtod(exthdrs.ip6e_hbh, u_char *) = IPPROTO_FRAGMENT;
934 } else {
935 nextproto = ip6->ip6_nxt;
936 ip6->ip6_nxt = IPPROTO_FRAGMENT;
937 }
938
939 /*
940 * Loop through length of segment after first fragment,
941 * make new header and copy data of each part and link onto
942 * chain.
943 */
944 m0 = m;
945 for (off = hlen; off < tlen; off += len) {
946 m = m_gethdr(M_NOWAIT, MT_DATA);
947 if (!m) {
948 error = ENOBUFS;
949 IP6STAT_INC(ip6s_odropped);
950 goto sendorfree;
951 }
952 m->m_flags = m0->m_flags & M_COPYFLAGS;
953 *mnext = m;
954 mnext = &m->m_nextpkt;
955 m->m_data += max_linkhdr;
956 mhip6 = mtod(m, struct ip6_hdr *);
957 *mhip6 = *ip6;
958 m->m_len = sizeof(*mhip6);
959 error = ip6_insertfraghdr(m0, m, hlen, &ip6f);
960 if (error) {
961 IP6STAT_INC(ip6s_odropped);
962 goto sendorfree;
963 }
964 ip6f->ip6f_offlg = htons((u_short)((off - hlen) & ~7));
965 if (off + len >= tlen)
966 len = tlen - off;
967 else
968 ip6f->ip6f_offlg |= IP6F_MORE_FRAG;
969 mhip6->ip6_plen = htons((u_short)(len + hlen +
970 sizeof(*ip6f) - sizeof(struct ip6_hdr)));
971 if ((m_frgpart = m_copy(m0, off, len)) == 0) {
972 error = ENOBUFS;
973 IP6STAT_INC(ip6s_odropped);
974 goto sendorfree;
975 }
976 m_cat(m, m_frgpart);
977 m->m_pkthdr.len = len + hlen + sizeof(*ip6f);
978 m->m_pkthdr.fibnum = m0->m_pkthdr.fibnum;
979 m->m_pkthdr.rcvif = NULL;
980 ip6f->ip6f_reserved = 0;
981 ip6f->ip6f_ident = id;
982 ip6f->ip6f_nxt = nextproto;
983 IP6STAT_INC(ip6s_ofragments);
984 in6_ifstat_inc(ifp, ifs6_out_fragcreat);
985 }
986
987 in6_ifstat_inc(ifp, ifs6_out_fragok);
988 }
989
990 /*
991 * Remove leading garbages.
992 */
993 sendorfree:
994 m = m0->m_nextpkt;
995 m0->m_nextpkt = 0;
996 m_freem(m0);
997 for (m0 = m; m; m = m0) {
998 m0 = m->m_nextpkt;
999 m->m_nextpkt = 0;
1000 if (error == 0) {
1001 /* Record statistics for this interface address. */
1002 if (ia) {
1003 ia->ia_ifa.if_opackets++;
1004 ia->ia_ifa.if_obytes += m->m_pkthdr.len;
1005 }
1006 error = nd6_output(ifp, origifp, m, dst, ro->ro_rt);
1007 } else
1008 m_freem(m);
1009 }
1010
1011 if (error == 0)
1012 IP6STAT_INC(ip6s_fragmented);
1013
1014 done:
1015 if (ro == &ip6route)
1016 RO_RTFREE(ro);
1017 if (ro_pmtu == &ip6route)
1018 RO_RTFREE(ro_pmtu);
1019 return (error);
1020
1021 freehdrs:
1022 m_freem(exthdrs.ip6e_hbh); /* m_freem will check if mbuf is 0 */
1023 m_freem(exthdrs.ip6e_dest1);
1024 m_freem(exthdrs.ip6e_rthdr);
1025 m_freem(exthdrs.ip6e_dest2);
1026 /* FALLTHROUGH */
1027 bad:
1028 if (m)
1029 m_freem(m);
1030 goto done;
1031 }
1032
1033 static int
ip6_copyexthdr(struct mbuf ** mp,caddr_t hdr,int hlen)1034 ip6_copyexthdr(struct mbuf **mp, caddr_t hdr, int hlen)
1035 {
1036 struct mbuf *m;
1037
1038 if (hlen > MCLBYTES)
1039 return (ENOBUFS); /* XXX */
1040
1041 if (hlen > MLEN)
1042 m = m_getcl(M_NOWAIT, MT_DATA, 0);
1043 else
1044 m = m_get(M_NOWAIT, MT_DATA);
1045 if (m == NULL)
1046 return (ENOBUFS);
1047 m->m_len = hlen;
1048 if (hdr)
1049 bcopy(hdr, mtod(m, caddr_t), hlen);
1050
1051 *mp = m;
1052 return (0);
1053 }
1054
1055 /*
1056 * Insert jumbo payload option.
1057 */
1058 static int
ip6_insert_jumboopt(struct ip6_exthdrs * exthdrs,u_int32_t plen)1059 ip6_insert_jumboopt(struct ip6_exthdrs *exthdrs, u_int32_t plen)
1060 {
1061 struct mbuf *mopt;
1062 u_char *optbuf;
1063 u_int32_t v;
1064
1065 #define JUMBOOPTLEN 8 /* length of jumbo payload option and padding */
1066
1067 /*
1068 * If there is no hop-by-hop options header, allocate new one.
1069 * If there is one but it doesn't have enough space to store the
1070 * jumbo payload option, allocate a cluster to store the whole options.
1071 * Otherwise, use it to store the options.
1072 */
1073 if (exthdrs->ip6e_hbh == 0) {
1074 mopt = m_get(M_NOWAIT, MT_DATA);
1075 if (mopt == NULL)
1076 return (ENOBUFS);
1077 mopt->m_len = JUMBOOPTLEN;
1078 optbuf = mtod(mopt, u_char *);
1079 optbuf[1] = 0; /* = ((JUMBOOPTLEN) >> 3) - 1 */
1080 exthdrs->ip6e_hbh = mopt;
1081 } else {
1082 struct ip6_hbh *hbh;
1083
1084 mopt = exthdrs->ip6e_hbh;
1085 if (M_TRAILINGSPACE(mopt) < JUMBOOPTLEN) {
1086 /*
1087 * XXX assumption:
1088 * - exthdrs->ip6e_hbh is not referenced from places
1089 * other than exthdrs.
1090 * - exthdrs->ip6e_hbh is not an mbuf chain.
1091 */
1092 int oldoptlen = mopt->m_len;
1093 struct mbuf *n;
1094
1095 /*
1096 * XXX: give up if the whole (new) hbh header does
1097 * not fit even in an mbuf cluster.
1098 */
1099 if (oldoptlen + JUMBOOPTLEN > MCLBYTES)
1100 return (ENOBUFS);
1101
1102 /*
1103 * As a consequence, we must always prepare a cluster
1104 * at this point.
1105 */
1106 n = m_getcl(M_NOWAIT, MT_DATA, 0);
1107 if (n == NULL)
1108 return (ENOBUFS);
1109 n->m_len = oldoptlen + JUMBOOPTLEN;
1110 bcopy(mtod(mopt, caddr_t), mtod(n, caddr_t),
1111 oldoptlen);
1112 optbuf = mtod(n, caddr_t) + oldoptlen;
1113 m_freem(mopt);
1114 mopt = exthdrs->ip6e_hbh = n;
1115 } else {
1116 optbuf = mtod(mopt, u_char *) + mopt->m_len;
1117 mopt->m_len += JUMBOOPTLEN;
1118 }
1119 optbuf[0] = IP6OPT_PADN;
1120 optbuf[1] = 1;
1121
1122 /*
1123 * Adjust the header length according to the pad and
1124 * the jumbo payload option.
1125 */
1126 hbh = mtod(mopt, struct ip6_hbh *);
1127 hbh->ip6h_len += (JUMBOOPTLEN >> 3);
1128 }
1129
1130 /* fill in the option. */
1131 optbuf[2] = IP6OPT_JUMBO;
1132 optbuf[3] = 4;
1133 v = (u_int32_t)htonl(plen + JUMBOOPTLEN);
1134 bcopy(&v, &optbuf[4], sizeof(u_int32_t));
1135
1136 /* finally, adjust the packet header length */
1137 exthdrs->ip6e_ip6->m_pkthdr.len += JUMBOOPTLEN;
1138
1139 return (0);
1140 #undef JUMBOOPTLEN
1141 }
1142
1143 /*
1144 * Insert fragment header and copy unfragmentable header portions.
1145 */
1146 static int
ip6_insertfraghdr(struct mbuf * m0,struct mbuf * m,int hlen,struct ip6_frag ** frghdrp)1147 ip6_insertfraghdr(struct mbuf *m0, struct mbuf *m, int hlen,
1148 struct ip6_frag **frghdrp)
1149 {
1150 struct mbuf *n, *mlast;
1151
1152 if (hlen > sizeof(struct ip6_hdr)) {
1153 n = m_copym(m0, sizeof(struct ip6_hdr),
1154 hlen - sizeof(struct ip6_hdr), M_NOWAIT);
1155 if (n == 0)
1156 return (ENOBUFS);
1157 m->m_next = n;
1158 } else
1159 n = m;
1160
1161 /* Search for the last mbuf of unfragmentable part. */
1162 for (mlast = n; mlast->m_next; mlast = mlast->m_next)
1163 ;
1164
1165 if ((mlast->m_flags & M_EXT) == 0 &&
1166 M_TRAILINGSPACE(mlast) >= sizeof(struct ip6_frag)) {
1167 /* use the trailing space of the last mbuf for the fragment hdr */
1168 *frghdrp = (struct ip6_frag *)(mtod(mlast, caddr_t) +
1169 mlast->m_len);
1170 mlast->m_len += sizeof(struct ip6_frag);
1171 m->m_pkthdr.len += sizeof(struct ip6_frag);
1172 } else {
1173 /* allocate a new mbuf for the fragment header */
1174 struct mbuf *mfrg;
1175
1176 mfrg = m_get(M_NOWAIT, MT_DATA);
1177 if (mfrg == NULL)
1178 return (ENOBUFS);
1179 mfrg->m_len = sizeof(struct ip6_frag);
1180 *frghdrp = mtod(mfrg, struct ip6_frag *);
1181 mlast->m_next = mfrg;
1182 }
1183
1184 return (0);
1185 }
1186
1187 static int
ip6_getpmtu(struct route_in6 * ro_pmtu,struct route_in6 * ro,struct ifnet * ifp,struct in6_addr * dst,u_long * mtup,int * alwaysfragp,u_int fibnum)1188 ip6_getpmtu(struct route_in6 *ro_pmtu, struct route_in6 *ro,
1189 struct ifnet *ifp, struct in6_addr *dst, u_long *mtup,
1190 int *alwaysfragp, u_int fibnum)
1191 {
1192 u_int32_t mtu = 0;
1193 int alwaysfrag = 0;
1194 int error = 0;
1195
1196 if (ro_pmtu != ro) {
1197 /* The first hop and the final destination may differ. */
1198 struct sockaddr_in6 *sa6_dst =
1199 (struct sockaddr_in6 *)&ro_pmtu->ro_dst;
1200 if (ro_pmtu->ro_rt &&
1201 ((ro_pmtu->ro_rt->rt_flags & RTF_UP) == 0 ||
1202 !IN6_ARE_ADDR_EQUAL(&sa6_dst->sin6_addr, dst))) {
1203 RTFREE(ro_pmtu->ro_rt);
1204 ro_pmtu->ro_rt = (struct rtentry *)NULL;
1205 }
1206 if (ro_pmtu->ro_rt == NULL) {
1207 bzero(sa6_dst, sizeof(*sa6_dst));
1208 sa6_dst->sin6_family = AF_INET6;
1209 sa6_dst->sin6_len = sizeof(struct sockaddr_in6);
1210 sa6_dst->sin6_addr = *dst;
1211
1212 in6_rtalloc(ro_pmtu, fibnum);
1213 }
1214 }
1215 if (ro_pmtu->ro_rt) {
1216 u_int32_t ifmtu;
1217 struct in_conninfo inc;
1218
1219 bzero(&inc, sizeof(inc));
1220 inc.inc_flags |= INC_ISIPV6;
1221 inc.inc6_faddr = *dst;
1222
1223 if (ifp == NULL)
1224 ifp = ro_pmtu->ro_rt->rt_ifp;
1225 ifmtu = IN6_LINKMTU(ifp);
1226 mtu = tcp_hc_getmtu(&inc);
1227 if (mtu)
1228 mtu = min(mtu, ro_pmtu->ro_rt->rt_mtu);
1229 else
1230 mtu = ro_pmtu->ro_rt->rt_mtu;
1231 if (mtu == 0)
1232 mtu = ifmtu;
1233 else if (mtu < IPV6_MMTU) {
1234 /*
1235 * RFC2460 section 5, last paragraph:
1236 * if we record ICMPv6 too big message with
1237 * mtu < IPV6_MMTU, transmit packets sized IPV6_MMTU
1238 * or smaller, with framgent header attached.
1239 * (fragment header is needed regardless from the
1240 * packet size, for translators to identify packets)
1241 */
1242 alwaysfrag = 1;
1243 mtu = IPV6_MMTU;
1244 } else if (mtu > ifmtu) {
1245 /*
1246 * The MTU on the route is larger than the MTU on
1247 * the interface! This shouldn't happen, unless the
1248 * MTU of the interface has been changed after the
1249 * interface was brought up. Change the MTU in the
1250 * route to match the interface MTU (as long as the
1251 * field isn't locked).
1252 */
1253 mtu = ifmtu;
1254 ro_pmtu->ro_rt->rt_mtu = mtu;
1255 }
1256 } else if (ifp) {
1257 mtu = IN6_LINKMTU(ifp);
1258 } else
1259 error = EHOSTUNREACH; /* XXX */
1260
1261 *mtup = mtu;
1262 if (alwaysfragp)
1263 *alwaysfragp = alwaysfrag;
1264 return (error);
1265 }
1266
1267 /*
1268 * IP6 socket option processing.
1269 */
1270 int
ip6_ctloutput(struct socket * so,struct sockopt * sopt)1271 ip6_ctloutput(struct socket *so, struct sockopt *sopt)
1272 {
1273 int optdatalen, uproto;
1274 void *optdata;
1275 struct inpcb *in6p = sotoinpcb(so);
1276 int error, optval;
1277 int level, op, optname;
1278 int optlen;
1279 struct thread *td;
1280
1281 level = sopt->sopt_level;
1282 op = sopt->sopt_dir;
1283 optname = sopt->sopt_name;
1284 optlen = sopt->sopt_valsize;
1285 td = sopt->sopt_td;
1286 error = 0;
1287 optval = 0;
1288 uproto = (int)so->so_proto->pr_protocol;
1289
1290 if (level != IPPROTO_IPV6) {
1291 error = EINVAL;
1292
1293 if (sopt->sopt_level == SOL_SOCKET &&
1294 sopt->sopt_dir == SOPT_SET) {
1295 switch (sopt->sopt_name) {
1296 case SO_REUSEADDR:
1297 INP_WLOCK(in6p);
1298 if ((so->so_options & SO_REUSEADDR) != 0)
1299 in6p->inp_flags2 |= INP_REUSEADDR;
1300 else
1301 in6p->inp_flags2 &= ~INP_REUSEADDR;
1302 INP_WUNLOCK(in6p);
1303 error = 0;
1304 break;
1305 case SO_REUSEPORT:
1306 INP_WLOCK(in6p);
1307 if ((so->so_options & SO_REUSEPORT) != 0)
1308 in6p->inp_flags2 |= INP_REUSEPORT;
1309 else
1310 in6p->inp_flags2 &= ~INP_REUSEPORT;
1311 INP_WUNLOCK(in6p);
1312 error = 0;
1313 break;
1314 case SO_SETFIB:
1315 INP_WLOCK(in6p);
1316 in6p->inp_inc.inc_fibnum = so->so_fibnum;
1317 INP_WUNLOCK(in6p);
1318 error = 0;
1319 break;
1320 default:
1321 break;
1322 }
1323 }
1324 } else { /* level == IPPROTO_IPV6 */
1325 switch (op) {
1326
1327 case SOPT_SET:
1328 switch (optname) {
1329 case IPV6_2292PKTOPTIONS:
1330 #ifdef IPV6_PKTOPTIONS
1331 case IPV6_PKTOPTIONS:
1332 #endif
1333 {
1334 struct mbuf *m;
1335
1336 error = soopt_getm(sopt, &m); /* XXX */
1337 if (error != 0)
1338 break;
1339 error = soopt_mcopyin(sopt, m); /* XXX */
1340 if (error != 0)
1341 break;
1342 error = ip6_pcbopts(&in6p->in6p_outputopts,
1343 m, so, sopt);
1344 m_freem(m); /* XXX */
1345 break;
1346 }
1347
1348 /*
1349 * Use of some Hop-by-Hop options or some
1350 * Destination options, might require special
1351 * privilege. That is, normal applications
1352 * (without special privilege) might be forbidden
1353 * from setting certain options in outgoing packets,
1354 * and might never see certain options in received
1355 * packets. [RFC 2292 Section 6]
1356 * KAME specific note:
1357 * KAME prevents non-privileged users from sending or
1358 * receiving ANY hbh/dst options in order to avoid
1359 * overhead of parsing options in the kernel.
1360 */
1361 case IPV6_RECVHOPOPTS:
1362 case IPV6_RECVDSTOPTS:
1363 case IPV6_RECVRTHDRDSTOPTS:
1364 if (td != NULL) {
1365 error = priv_check(td,
1366 PRIV_NETINET_SETHDROPTS);
1367 if (error)
1368 break;
1369 }
1370 /* FALLTHROUGH */
1371 case IPV6_UNICAST_HOPS:
1372 case IPV6_HOPLIMIT:
1373 case IPV6_FAITH:
1374
1375 case IPV6_RECVPKTINFO:
1376 case IPV6_RECVHOPLIMIT:
1377 case IPV6_RECVRTHDR:
1378 case IPV6_RECVPATHMTU:
1379 case IPV6_RECVTCLASS:
1380 case IPV6_V6ONLY:
1381 case IPV6_AUTOFLOWLABEL:
1382 case IPV6_BINDANY:
1383 if (optname == IPV6_BINDANY && td != NULL) {
1384 error = priv_check(td,
1385 PRIV_NETINET_BINDANY);
1386 if (error)
1387 break;
1388 }
1389
1390 if (optlen != sizeof(int)) {
1391 error = EINVAL;
1392 break;
1393 }
1394 error = sooptcopyin(sopt, &optval,
1395 sizeof optval, sizeof optval);
1396 if (error)
1397 break;
1398 switch (optname) {
1399
1400 case IPV6_UNICAST_HOPS:
1401 if (optval < -1 || optval >= 256)
1402 error = EINVAL;
1403 else {
1404 /* -1 = kernel default */
1405 in6p->in6p_hops = optval;
1406 if ((in6p->inp_vflag &
1407 INP_IPV4) != 0)
1408 in6p->inp_ip_ttl = optval;
1409 }
1410 break;
1411 #define OPTSET(bit) \
1412 do { \
1413 INP_WLOCK(in6p); \
1414 if (optval) \
1415 in6p->inp_flags |= (bit); \
1416 else \
1417 in6p->inp_flags &= ~(bit); \
1418 INP_WUNLOCK(in6p); \
1419 } while (/*CONSTCOND*/ 0)
1420 #define OPTSET2292(bit) \
1421 do { \
1422 INP_WLOCK(in6p); \
1423 in6p->inp_flags |= IN6P_RFC2292; \
1424 if (optval) \
1425 in6p->inp_flags |= (bit); \
1426 else \
1427 in6p->inp_flags &= ~(bit); \
1428 INP_WUNLOCK(in6p); \
1429 } while (/*CONSTCOND*/ 0)
1430 #define OPTBIT(bit) (in6p->inp_flags & (bit) ? 1 : 0)
1431
1432 case IPV6_RECVPKTINFO:
1433 /* cannot mix with RFC2292 */
1434 if (OPTBIT(IN6P_RFC2292)) {
1435 error = EINVAL;
1436 break;
1437 }
1438 OPTSET(IN6P_PKTINFO);
1439 break;
1440
1441 case IPV6_HOPLIMIT:
1442 {
1443 struct ip6_pktopts **optp;
1444
1445 /* cannot mix with RFC2292 */
1446 if (OPTBIT(IN6P_RFC2292)) {
1447 error = EINVAL;
1448 break;
1449 }
1450 optp = &in6p->in6p_outputopts;
1451 error = ip6_pcbopt(IPV6_HOPLIMIT,
1452 (u_char *)&optval, sizeof(optval),
1453 optp, (td != NULL) ? td->td_ucred :
1454 NULL, uproto);
1455 break;
1456 }
1457
1458 case IPV6_RECVHOPLIMIT:
1459 /* cannot mix with RFC2292 */
1460 if (OPTBIT(IN6P_RFC2292)) {
1461 error = EINVAL;
1462 break;
1463 }
1464 OPTSET(IN6P_HOPLIMIT);
1465 break;
1466
1467 case IPV6_RECVHOPOPTS:
1468 /* cannot mix with RFC2292 */
1469 if (OPTBIT(IN6P_RFC2292)) {
1470 error = EINVAL;
1471 break;
1472 }
1473 OPTSET(IN6P_HOPOPTS);
1474 break;
1475
1476 case IPV6_RECVDSTOPTS:
1477 /* cannot mix with RFC2292 */
1478 if (OPTBIT(IN6P_RFC2292)) {
1479 error = EINVAL;
1480 break;
1481 }
1482 OPTSET(IN6P_DSTOPTS);
1483 break;
1484
1485 case IPV6_RECVRTHDRDSTOPTS:
1486 /* cannot mix with RFC2292 */
1487 if (OPTBIT(IN6P_RFC2292)) {
1488 error = EINVAL;
1489 break;
1490 }
1491 OPTSET(IN6P_RTHDRDSTOPTS);
1492 break;
1493
1494 case IPV6_RECVRTHDR:
1495 /* cannot mix with RFC2292 */
1496 if (OPTBIT(IN6P_RFC2292)) {
1497 error = EINVAL;
1498 break;
1499 }
1500 OPTSET(IN6P_RTHDR);
1501 break;
1502
1503 case IPV6_FAITH:
1504 OPTSET(INP_FAITH);
1505 break;
1506
1507 case IPV6_RECVPATHMTU:
1508 /*
1509 * We ignore this option for TCP
1510 * sockets.
1511 * (RFC3542 leaves this case
1512 * unspecified.)
1513 */
1514 if (uproto != IPPROTO_TCP)
1515 OPTSET(IN6P_MTU);
1516 break;
1517
1518 case IPV6_V6ONLY:
1519 /*
1520 * make setsockopt(IPV6_V6ONLY)
1521 * available only prior to bind(2).
1522 * see ipng mailing list, Jun 22 2001.
1523 */
1524 if (in6p->inp_lport ||
1525 !IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr)) {
1526 error = EINVAL;
1527 break;
1528 }
1529 OPTSET(IN6P_IPV6_V6ONLY);
1530 if (optval)
1531 in6p->inp_vflag &= ~INP_IPV4;
1532 else
1533 in6p->inp_vflag |= INP_IPV4;
1534 break;
1535 case IPV6_RECVTCLASS:
1536 /* cannot mix with RFC2292 XXX */
1537 if (OPTBIT(IN6P_RFC2292)) {
1538 error = EINVAL;
1539 break;
1540 }
1541 OPTSET(IN6P_TCLASS);
1542 break;
1543 case IPV6_AUTOFLOWLABEL:
1544 OPTSET(IN6P_AUTOFLOWLABEL);
1545 break;
1546
1547 case IPV6_BINDANY:
1548 OPTSET(INP_BINDANY);
1549 break;
1550 }
1551 break;
1552
1553 case IPV6_TCLASS:
1554 case IPV6_DONTFRAG:
1555 case IPV6_USE_MIN_MTU:
1556 case IPV6_PREFER_TEMPADDR:
1557 if (optlen != sizeof(optval)) {
1558 error = EINVAL;
1559 break;
1560 }
1561 error = sooptcopyin(sopt, &optval,
1562 sizeof optval, sizeof optval);
1563 if (error)
1564 break;
1565 {
1566 struct ip6_pktopts **optp;
1567 optp = &in6p->in6p_outputopts;
1568 error = ip6_pcbopt(optname,
1569 (u_char *)&optval, sizeof(optval),
1570 optp, (td != NULL) ? td->td_ucred :
1571 NULL, uproto);
1572 break;
1573 }
1574
1575 case IPV6_2292PKTINFO:
1576 case IPV6_2292HOPLIMIT:
1577 case IPV6_2292HOPOPTS:
1578 case IPV6_2292DSTOPTS:
1579 case IPV6_2292RTHDR:
1580 /* RFC 2292 */
1581 if (optlen != sizeof(int)) {
1582 error = EINVAL;
1583 break;
1584 }
1585 error = sooptcopyin(sopt, &optval,
1586 sizeof optval, sizeof optval);
1587 if (error)
1588 break;
1589 switch (optname) {
1590 case IPV6_2292PKTINFO:
1591 OPTSET2292(IN6P_PKTINFO);
1592 break;
1593 case IPV6_2292HOPLIMIT:
1594 OPTSET2292(IN6P_HOPLIMIT);
1595 break;
1596 case IPV6_2292HOPOPTS:
1597 /*
1598 * Check super-user privilege.
1599 * See comments for IPV6_RECVHOPOPTS.
1600 */
1601 if (td != NULL) {
1602 error = priv_check(td,
1603 PRIV_NETINET_SETHDROPTS);
1604 if (error)
1605 return (error);
1606 }
1607 OPTSET2292(IN6P_HOPOPTS);
1608 break;
1609 case IPV6_2292DSTOPTS:
1610 if (td != NULL) {
1611 error = priv_check(td,
1612 PRIV_NETINET_SETHDROPTS);
1613 if (error)
1614 return (error);
1615 }
1616 OPTSET2292(IN6P_DSTOPTS|IN6P_RTHDRDSTOPTS); /* XXX */
1617 break;
1618 case IPV6_2292RTHDR:
1619 OPTSET2292(IN6P_RTHDR);
1620 break;
1621 }
1622 break;
1623 case IPV6_PKTINFO:
1624 case IPV6_HOPOPTS:
1625 case IPV6_RTHDR:
1626 case IPV6_DSTOPTS:
1627 case IPV6_RTHDRDSTOPTS:
1628 case IPV6_NEXTHOP:
1629 {
1630 /* new advanced API (RFC3542) */
1631 u_char *optbuf;
1632 u_char optbuf_storage[MCLBYTES];
1633 int optlen;
1634 struct ip6_pktopts **optp;
1635
1636 /* cannot mix with RFC2292 */
1637 if (OPTBIT(IN6P_RFC2292)) {
1638 error = EINVAL;
1639 break;
1640 }
1641
1642 /*
1643 * We only ensure valsize is not too large
1644 * here. Further validation will be done
1645 * later.
1646 */
1647 error = sooptcopyin(sopt, optbuf_storage,
1648 sizeof(optbuf_storage), 0);
1649 if (error)
1650 break;
1651 optlen = sopt->sopt_valsize;
1652 optbuf = optbuf_storage;
1653 optp = &in6p->in6p_outputopts;
1654 error = ip6_pcbopt(optname, optbuf, optlen,
1655 optp, (td != NULL) ? td->td_ucred : NULL,
1656 uproto);
1657 break;
1658 }
1659 #undef OPTSET
1660
1661 case IPV6_MULTICAST_IF:
1662 case IPV6_MULTICAST_HOPS:
1663 case IPV6_MULTICAST_LOOP:
1664 case IPV6_JOIN_GROUP:
1665 case IPV6_LEAVE_GROUP:
1666 case IPV6_MSFILTER:
1667 case MCAST_BLOCK_SOURCE:
1668 case MCAST_UNBLOCK_SOURCE:
1669 case MCAST_JOIN_GROUP:
1670 case MCAST_LEAVE_GROUP:
1671 case MCAST_JOIN_SOURCE_GROUP:
1672 case MCAST_LEAVE_SOURCE_GROUP:
1673 error = ip6_setmoptions(in6p, sopt);
1674 break;
1675
1676 case IPV6_PORTRANGE:
1677 error = sooptcopyin(sopt, &optval,
1678 sizeof optval, sizeof optval);
1679 if (error)
1680 break;
1681
1682 INP_WLOCK(in6p);
1683 switch (optval) {
1684 case IPV6_PORTRANGE_DEFAULT:
1685 in6p->inp_flags &= ~(INP_LOWPORT);
1686 in6p->inp_flags &= ~(INP_HIGHPORT);
1687 break;
1688
1689 case IPV6_PORTRANGE_HIGH:
1690 in6p->inp_flags &= ~(INP_LOWPORT);
1691 in6p->inp_flags |= INP_HIGHPORT;
1692 break;
1693
1694 case IPV6_PORTRANGE_LOW:
1695 in6p->inp_flags &= ~(INP_HIGHPORT);
1696 in6p->inp_flags |= INP_LOWPORT;
1697 break;
1698
1699 default:
1700 error = EINVAL;
1701 break;
1702 }
1703 INP_WUNLOCK(in6p);
1704 break;
1705
1706 #ifdef IPSEC
1707 case IPV6_IPSEC_POLICY:
1708 {
1709 caddr_t req;
1710 struct mbuf *m;
1711
1712 if ((error = soopt_getm(sopt, &m)) != 0) /* XXX */
1713 break;
1714 if ((error = soopt_mcopyin(sopt, m)) != 0) /* XXX */
1715 break;
1716 req = mtod(m, caddr_t);
1717 error = ipsec_set_policy(in6p, optname, req,
1718 m->m_len, (sopt->sopt_td != NULL) ?
1719 sopt->sopt_td->td_ucred : NULL);
1720 m_freem(m);
1721 break;
1722 }
1723 #endif /* IPSEC */
1724
1725 default:
1726 error = ENOPROTOOPT;
1727 break;
1728 }
1729 break;
1730
1731 case SOPT_GET:
1732 switch (optname) {
1733
1734 case IPV6_2292PKTOPTIONS:
1735 #ifdef IPV6_PKTOPTIONS
1736 case IPV6_PKTOPTIONS:
1737 #endif
1738 /*
1739 * RFC3542 (effectively) deprecated the
1740 * semantics of the 2292-style pktoptions.
1741 * Since it was not reliable in nature (i.e.,
1742 * applications had to expect the lack of some
1743 * information after all), it would make sense
1744 * to simplify this part by always returning
1745 * empty data.
1746 */
1747 sopt->sopt_valsize = 0;
1748 break;
1749
1750 case IPV6_RECVHOPOPTS:
1751 case IPV6_RECVDSTOPTS:
1752 case IPV6_RECVRTHDRDSTOPTS:
1753 case IPV6_UNICAST_HOPS:
1754 case IPV6_RECVPKTINFO:
1755 case IPV6_RECVHOPLIMIT:
1756 case IPV6_RECVRTHDR:
1757 case IPV6_RECVPATHMTU:
1758
1759 case IPV6_FAITH:
1760 case IPV6_V6ONLY:
1761 case IPV6_PORTRANGE:
1762 case IPV6_RECVTCLASS:
1763 case IPV6_AUTOFLOWLABEL:
1764 case IPV6_BINDANY:
1765 switch (optname) {
1766
1767 case IPV6_RECVHOPOPTS:
1768 optval = OPTBIT(IN6P_HOPOPTS);
1769 break;
1770
1771 case IPV6_RECVDSTOPTS:
1772 optval = OPTBIT(IN6P_DSTOPTS);
1773 break;
1774
1775 case IPV6_RECVRTHDRDSTOPTS:
1776 optval = OPTBIT(IN6P_RTHDRDSTOPTS);
1777 break;
1778
1779 case IPV6_UNICAST_HOPS:
1780 optval = in6p->in6p_hops;
1781 break;
1782
1783 case IPV6_RECVPKTINFO:
1784 optval = OPTBIT(IN6P_PKTINFO);
1785 break;
1786
1787 case IPV6_RECVHOPLIMIT:
1788 optval = OPTBIT(IN6P_HOPLIMIT);
1789 break;
1790
1791 case IPV6_RECVRTHDR:
1792 optval = OPTBIT(IN6P_RTHDR);
1793 break;
1794
1795 case IPV6_RECVPATHMTU:
1796 optval = OPTBIT(IN6P_MTU);
1797 break;
1798
1799 case IPV6_FAITH:
1800 optval = OPTBIT(INP_FAITH);
1801 break;
1802
1803 case IPV6_V6ONLY:
1804 optval = OPTBIT(IN6P_IPV6_V6ONLY);
1805 break;
1806
1807 case IPV6_PORTRANGE:
1808 {
1809 int flags;
1810 flags = in6p->inp_flags;
1811 if (flags & INP_HIGHPORT)
1812 optval = IPV6_PORTRANGE_HIGH;
1813 else if (flags & INP_LOWPORT)
1814 optval = IPV6_PORTRANGE_LOW;
1815 else
1816 optval = 0;
1817 break;
1818 }
1819 case IPV6_RECVTCLASS:
1820 optval = OPTBIT(IN6P_TCLASS);
1821 break;
1822
1823 case IPV6_AUTOFLOWLABEL:
1824 optval = OPTBIT(IN6P_AUTOFLOWLABEL);
1825 break;
1826
1827 case IPV6_BINDANY:
1828 optval = OPTBIT(INP_BINDANY);
1829 break;
1830 }
1831 if (error)
1832 break;
1833 error = sooptcopyout(sopt, &optval,
1834 sizeof optval);
1835 break;
1836
1837 case IPV6_PATHMTU:
1838 {
1839 u_long pmtu = 0;
1840 struct ip6_mtuinfo mtuinfo;
1841 struct route_in6 sro;
1842
1843 bzero(&sro, sizeof(sro));
1844
1845 if (!(so->so_state & SS_ISCONNECTED))
1846 return (ENOTCONN);
1847 /*
1848 * XXX: we dot not consider the case of source
1849 * routing, or optional information to specify
1850 * the outgoing interface.
1851 */
1852 error = ip6_getpmtu(&sro, NULL, NULL,
1853 &in6p->in6p_faddr, &pmtu, NULL,
1854 so->so_fibnum);
1855 if (sro.ro_rt)
1856 RTFREE(sro.ro_rt);
1857 if (error)
1858 break;
1859 if (pmtu > IPV6_MAXPACKET)
1860 pmtu = IPV6_MAXPACKET;
1861
1862 bzero(&mtuinfo, sizeof(mtuinfo));
1863 mtuinfo.ip6m_mtu = (u_int32_t)pmtu;
1864 optdata = (void *)&mtuinfo;
1865 optdatalen = sizeof(mtuinfo);
1866 error = sooptcopyout(sopt, optdata,
1867 optdatalen);
1868 break;
1869 }
1870
1871 case IPV6_2292PKTINFO:
1872 case IPV6_2292HOPLIMIT:
1873 case IPV6_2292HOPOPTS:
1874 case IPV6_2292RTHDR:
1875 case IPV6_2292DSTOPTS:
1876 switch (optname) {
1877 case IPV6_2292PKTINFO:
1878 optval = OPTBIT(IN6P_PKTINFO);
1879 break;
1880 case IPV6_2292HOPLIMIT:
1881 optval = OPTBIT(IN6P_HOPLIMIT);
1882 break;
1883 case IPV6_2292HOPOPTS:
1884 optval = OPTBIT(IN6P_HOPOPTS);
1885 break;
1886 case IPV6_2292RTHDR:
1887 optval = OPTBIT(IN6P_RTHDR);
1888 break;
1889 case IPV6_2292DSTOPTS:
1890 optval = OPTBIT(IN6P_DSTOPTS|IN6P_RTHDRDSTOPTS);
1891 break;
1892 }
1893 error = sooptcopyout(sopt, &optval,
1894 sizeof optval);
1895 break;
1896 case IPV6_PKTINFO:
1897 case IPV6_HOPOPTS:
1898 case IPV6_RTHDR:
1899 case IPV6_DSTOPTS:
1900 case IPV6_RTHDRDSTOPTS:
1901 case IPV6_NEXTHOP:
1902 case IPV6_TCLASS:
1903 case IPV6_DONTFRAG:
1904 case IPV6_USE_MIN_MTU:
1905 case IPV6_PREFER_TEMPADDR:
1906 error = ip6_getpcbopt(in6p->in6p_outputopts,
1907 optname, sopt);
1908 break;
1909
1910 case IPV6_MULTICAST_IF:
1911 case IPV6_MULTICAST_HOPS:
1912 case IPV6_MULTICAST_LOOP:
1913 case IPV6_MSFILTER:
1914 error = ip6_getmoptions(in6p, sopt);
1915 break;
1916
1917 #ifdef IPSEC
1918 case IPV6_IPSEC_POLICY:
1919 {
1920 caddr_t req = NULL;
1921 size_t len = 0;
1922 struct mbuf *m = NULL;
1923 struct mbuf **mp = &m;
1924 size_t ovalsize = sopt->sopt_valsize;
1925 caddr_t oval = (caddr_t)sopt->sopt_val;
1926
1927 error = soopt_getm(sopt, &m); /* XXX */
1928 if (error != 0)
1929 break;
1930 error = soopt_mcopyin(sopt, m); /* XXX */
1931 if (error != 0)
1932 break;
1933 sopt->sopt_valsize = ovalsize;
1934 sopt->sopt_val = oval;
1935 if (m) {
1936 req = mtod(m, caddr_t);
1937 len = m->m_len;
1938 }
1939 error = ipsec_get_policy(in6p, req, len, mp);
1940 if (error == 0)
1941 error = soopt_mcopyout(sopt, m); /* XXX */
1942 if (error == 0 && m)
1943 m_freem(m);
1944 break;
1945 }
1946 #endif /* IPSEC */
1947
1948 default:
1949 error = ENOPROTOOPT;
1950 break;
1951 }
1952 break;
1953 }
1954 }
1955 return (error);
1956 }
1957
1958 int
ip6_raw_ctloutput(struct socket * so,struct sockopt * sopt)1959 ip6_raw_ctloutput(struct socket *so, struct sockopt *sopt)
1960 {
1961 int error = 0, optval, optlen;
1962 const int icmp6off = offsetof(struct icmp6_hdr, icmp6_cksum);
1963 struct inpcb *in6p = sotoinpcb(so);
1964 int level, op, optname;
1965
1966 level = sopt->sopt_level;
1967 op = sopt->sopt_dir;
1968 optname = sopt->sopt_name;
1969 optlen = sopt->sopt_valsize;
1970
1971 if (level != IPPROTO_IPV6) {
1972 return (EINVAL);
1973 }
1974
1975 switch (optname) {
1976 case IPV6_CHECKSUM:
1977 /*
1978 * For ICMPv6 sockets, no modification allowed for checksum
1979 * offset, permit "no change" values to help existing apps.
1980 *
1981 * RFC3542 says: "An attempt to set IPV6_CHECKSUM
1982 * for an ICMPv6 socket will fail."
1983 * The current behavior does not meet RFC3542.
1984 */
1985 switch (op) {
1986 case SOPT_SET:
1987 if (optlen != sizeof(int)) {
1988 error = EINVAL;
1989 break;
1990 }
1991 error = sooptcopyin(sopt, &optval, sizeof(optval),
1992 sizeof(optval));
1993 if (error)
1994 break;
1995 if ((optval % 2) != 0) {
1996 /* the API assumes even offset values */
1997 error = EINVAL;
1998 } else if (so->so_proto->pr_protocol ==
1999 IPPROTO_ICMPV6) {
2000 if (optval != icmp6off)
2001 error = EINVAL;
2002 } else
2003 in6p->in6p_cksum = optval;
2004 break;
2005
2006 case SOPT_GET:
2007 if (so->so_proto->pr_protocol == IPPROTO_ICMPV6)
2008 optval = icmp6off;
2009 else
2010 optval = in6p->in6p_cksum;
2011
2012 error = sooptcopyout(sopt, &optval, sizeof(optval));
2013 break;
2014
2015 default:
2016 error = EINVAL;
2017 break;
2018 }
2019 break;
2020
2021 default:
2022 error = ENOPROTOOPT;
2023 break;
2024 }
2025
2026 return (error);
2027 }
2028
2029 /*
2030 * Set up IP6 options in pcb for insertion in output packets or
2031 * specifying behavior of outgoing packets.
2032 */
2033 static int
ip6_pcbopts(struct ip6_pktopts ** pktopt,struct mbuf * m,struct socket * so,struct sockopt * sopt)2034 ip6_pcbopts(struct ip6_pktopts **pktopt, struct mbuf *m,
2035 struct socket *so, struct sockopt *sopt)
2036 {
2037 struct ip6_pktopts *opt = *pktopt;
2038 int error = 0;
2039 struct thread *td = sopt->sopt_td;
2040
2041 /* turn off any old options. */
2042 if (opt) {
2043 #ifdef DIAGNOSTIC
2044 if (opt->ip6po_pktinfo || opt->ip6po_nexthop ||
2045 opt->ip6po_hbh || opt->ip6po_dest1 || opt->ip6po_dest2 ||
2046 opt->ip6po_rhinfo.ip6po_rhi_rthdr)
2047 printf("ip6_pcbopts: all specified options are cleared.\n");
2048 #endif
2049 ip6_clearpktopts(opt, -1);
2050 } else
2051 opt = malloc(sizeof(*opt), M_IP6OPT, M_WAITOK);
2052 *pktopt = NULL;
2053
2054 if (!m || m->m_len == 0) {
2055 /*
2056 * Only turning off any previous options, regardless of
2057 * whether the opt is just created or given.
2058 */
2059 free(opt, M_IP6OPT);
2060 return (0);
2061 }
2062
2063 /* set options specified by user. */
2064 if ((error = ip6_setpktopts(m, opt, NULL, (td != NULL) ?
2065 td->td_ucred : NULL, so->so_proto->pr_protocol)) != 0) {
2066 ip6_clearpktopts(opt, -1); /* XXX: discard all options */
2067 free(opt, M_IP6OPT);
2068 return (error);
2069 }
2070 *pktopt = opt;
2071 return (0);
2072 }
2073
2074 /*
2075 * initialize ip6_pktopts. beware that there are non-zero default values in
2076 * the struct.
2077 */
2078 void
ip6_initpktopts(struct ip6_pktopts * opt)2079 ip6_initpktopts(struct ip6_pktopts *opt)
2080 {
2081
2082 bzero(opt, sizeof(*opt));
2083 opt->ip6po_hlim = -1; /* -1 means default hop limit */
2084 opt->ip6po_tclass = -1; /* -1 means default traffic class */
2085 opt->ip6po_minmtu = IP6PO_MINMTU_MCASTONLY;
2086 opt->ip6po_prefer_tempaddr = IP6PO_TEMPADDR_SYSTEM;
2087 }
2088
2089 static int
ip6_pcbopt(int optname,u_char * buf,int len,struct ip6_pktopts ** pktopt,struct ucred * cred,int uproto)2090 ip6_pcbopt(int optname, u_char *buf, int len, struct ip6_pktopts **pktopt,
2091 struct ucred *cred, int uproto)
2092 {
2093 struct ip6_pktopts *opt;
2094
2095 if (*pktopt == NULL) {
2096 *pktopt = malloc(sizeof(struct ip6_pktopts), M_IP6OPT,
2097 M_WAITOK);
2098 ip6_initpktopts(*pktopt);
2099 }
2100 opt = *pktopt;
2101
2102 return (ip6_setpktopt(optname, buf, len, opt, cred, 1, 0, uproto));
2103 }
2104
2105 static int
ip6_getpcbopt(struct ip6_pktopts * pktopt,int optname,struct sockopt * sopt)2106 ip6_getpcbopt(struct ip6_pktopts *pktopt, int optname, struct sockopt *sopt)
2107 {
2108 void *optdata = NULL;
2109 int optdatalen = 0;
2110 struct ip6_ext *ip6e;
2111 int error = 0;
2112 struct in6_pktinfo null_pktinfo;
2113 int deftclass = 0, on;
2114 int defminmtu = IP6PO_MINMTU_MCASTONLY;
2115 int defpreftemp = IP6PO_TEMPADDR_SYSTEM;
2116
2117 switch (optname) {
2118 case IPV6_PKTINFO:
2119 if (pktopt && pktopt->ip6po_pktinfo)
2120 optdata = (void *)pktopt->ip6po_pktinfo;
2121 else {
2122 /* XXX: we don't have to do this every time... */
2123 bzero(&null_pktinfo, sizeof(null_pktinfo));
2124 optdata = (void *)&null_pktinfo;
2125 }
2126 optdatalen = sizeof(struct in6_pktinfo);
2127 break;
2128 case IPV6_TCLASS:
2129 if (pktopt && pktopt->ip6po_tclass >= 0)
2130 optdata = (void *)&pktopt->ip6po_tclass;
2131 else
2132 optdata = (void *)&deftclass;
2133 optdatalen = sizeof(int);
2134 break;
2135 case IPV6_HOPOPTS:
2136 if (pktopt && pktopt->ip6po_hbh) {
2137 optdata = (void *)pktopt->ip6po_hbh;
2138 ip6e = (struct ip6_ext *)pktopt->ip6po_hbh;
2139 optdatalen = (ip6e->ip6e_len + 1) << 3;
2140 }
2141 break;
2142 case IPV6_RTHDR:
2143 if (pktopt && pktopt->ip6po_rthdr) {
2144 optdata = (void *)pktopt->ip6po_rthdr;
2145 ip6e = (struct ip6_ext *)pktopt->ip6po_rthdr;
2146 optdatalen = (ip6e->ip6e_len + 1) << 3;
2147 }
2148 break;
2149 case IPV6_RTHDRDSTOPTS:
2150 if (pktopt && pktopt->ip6po_dest1) {
2151 optdata = (void *)pktopt->ip6po_dest1;
2152 ip6e = (struct ip6_ext *)pktopt->ip6po_dest1;
2153 optdatalen = (ip6e->ip6e_len + 1) << 3;
2154 }
2155 break;
2156 case IPV6_DSTOPTS:
2157 if (pktopt && pktopt->ip6po_dest2) {
2158 optdata = (void *)pktopt->ip6po_dest2;
2159 ip6e = (struct ip6_ext *)pktopt->ip6po_dest2;
2160 optdatalen = (ip6e->ip6e_len + 1) << 3;
2161 }
2162 break;
2163 case IPV6_NEXTHOP:
2164 if (pktopt && pktopt->ip6po_nexthop) {
2165 optdata = (void *)pktopt->ip6po_nexthop;
2166 optdatalen = pktopt->ip6po_nexthop->sa_len;
2167 }
2168 break;
2169 case IPV6_USE_MIN_MTU:
2170 if (pktopt)
2171 optdata = (void *)&pktopt->ip6po_minmtu;
2172 else
2173 optdata = (void *)&defminmtu;
2174 optdatalen = sizeof(int);
2175 break;
2176 case IPV6_DONTFRAG:
2177 if (pktopt && ((pktopt->ip6po_flags) & IP6PO_DONTFRAG))
2178 on = 1;
2179 else
2180 on = 0;
2181 optdata = (void *)&on;
2182 optdatalen = sizeof(on);
2183 break;
2184 case IPV6_PREFER_TEMPADDR:
2185 if (pktopt)
2186 optdata = (void *)&pktopt->ip6po_prefer_tempaddr;
2187 else
2188 optdata = (void *)&defpreftemp;
2189 optdatalen = sizeof(int);
2190 break;
2191 default: /* should not happen */
2192 #ifdef DIAGNOSTIC
2193 panic("ip6_getpcbopt: unexpected option\n");
2194 #endif
2195 return (ENOPROTOOPT);
2196 }
2197
2198 error = sooptcopyout(sopt, optdata, optdatalen);
2199
2200 return (error);
2201 }
2202
2203 void
ip6_clearpktopts(struct ip6_pktopts * pktopt,int optname)2204 ip6_clearpktopts(struct ip6_pktopts *pktopt, int optname)
2205 {
2206 if (pktopt == NULL)
2207 return;
2208
2209 if (optname == -1 || optname == IPV6_PKTINFO) {
2210 if (pktopt->ip6po_pktinfo)
2211 free(pktopt->ip6po_pktinfo, M_IP6OPT);
2212 pktopt->ip6po_pktinfo = NULL;
2213 }
2214 if (optname == -1 || optname == IPV6_HOPLIMIT)
2215 pktopt->ip6po_hlim = -1;
2216 if (optname == -1 || optname == IPV6_TCLASS)
2217 pktopt->ip6po_tclass = -1;
2218 if (optname == -1 || optname == IPV6_NEXTHOP) {
2219 if (pktopt->ip6po_nextroute.ro_rt) {
2220 RTFREE(pktopt->ip6po_nextroute.ro_rt);
2221 pktopt->ip6po_nextroute.ro_rt = NULL;
2222 }
2223 if (pktopt->ip6po_nexthop)
2224 free(pktopt->ip6po_nexthop, M_IP6OPT);
2225 pktopt->ip6po_nexthop = NULL;
2226 }
2227 if (optname == -1 || optname == IPV6_HOPOPTS) {
2228 if (pktopt->ip6po_hbh)
2229 free(pktopt->ip6po_hbh, M_IP6OPT);
2230 pktopt->ip6po_hbh = NULL;
2231 }
2232 if (optname == -1 || optname == IPV6_RTHDRDSTOPTS) {
2233 if (pktopt->ip6po_dest1)
2234 free(pktopt->ip6po_dest1, M_IP6OPT);
2235 pktopt->ip6po_dest1 = NULL;
2236 }
2237 if (optname == -1 || optname == IPV6_RTHDR) {
2238 if (pktopt->ip6po_rhinfo.ip6po_rhi_rthdr)
2239 free(pktopt->ip6po_rhinfo.ip6po_rhi_rthdr, M_IP6OPT);
2240 pktopt->ip6po_rhinfo.ip6po_rhi_rthdr = NULL;
2241 if (pktopt->ip6po_route.ro_rt) {
2242 RTFREE(pktopt->ip6po_route.ro_rt);
2243 pktopt->ip6po_route.ro_rt = NULL;
2244 }
2245 }
2246 if (optname == -1 || optname == IPV6_DSTOPTS) {
2247 if (pktopt->ip6po_dest2)
2248 free(pktopt->ip6po_dest2, M_IP6OPT);
2249 pktopt->ip6po_dest2 = NULL;
2250 }
2251 }
2252
2253 #define PKTOPT_EXTHDRCPY(type) \
2254 do {\
2255 if (src->type) {\
2256 int hlen = (((struct ip6_ext *)src->type)->ip6e_len + 1) << 3;\
2257 dst->type = malloc(hlen, M_IP6OPT, canwait);\
2258 if (dst->type == NULL && canwait == M_NOWAIT)\
2259 goto bad;\
2260 bcopy(src->type, dst->type, hlen);\
2261 }\
2262 } while (/*CONSTCOND*/ 0)
2263
2264 static int
copypktopts(struct ip6_pktopts * dst,struct ip6_pktopts * src,int canwait)2265 copypktopts(struct ip6_pktopts *dst, struct ip6_pktopts *src, int canwait)
2266 {
2267 if (dst == NULL || src == NULL) {
2268 printf("ip6_clearpktopts: invalid argument\n");
2269 return (EINVAL);
2270 }
2271
2272 dst->ip6po_hlim = src->ip6po_hlim;
2273 dst->ip6po_tclass = src->ip6po_tclass;
2274 dst->ip6po_flags = src->ip6po_flags;
2275 dst->ip6po_minmtu = src->ip6po_minmtu;
2276 dst->ip6po_prefer_tempaddr = src->ip6po_prefer_tempaddr;
2277 if (src->ip6po_pktinfo) {
2278 dst->ip6po_pktinfo = malloc(sizeof(*dst->ip6po_pktinfo),
2279 M_IP6OPT, canwait);
2280 if (dst->ip6po_pktinfo == NULL)
2281 goto bad;
2282 *dst->ip6po_pktinfo = *src->ip6po_pktinfo;
2283 }
2284 if (src->ip6po_nexthop) {
2285 dst->ip6po_nexthop = malloc(src->ip6po_nexthop->sa_len,
2286 M_IP6OPT, canwait);
2287 if (dst->ip6po_nexthop == NULL)
2288 goto bad;
2289 bcopy(src->ip6po_nexthop, dst->ip6po_nexthop,
2290 src->ip6po_nexthop->sa_len);
2291 }
2292 PKTOPT_EXTHDRCPY(ip6po_hbh);
2293 PKTOPT_EXTHDRCPY(ip6po_dest1);
2294 PKTOPT_EXTHDRCPY(ip6po_dest2);
2295 PKTOPT_EXTHDRCPY(ip6po_rthdr); /* not copy the cached route */
2296 return (0);
2297
2298 bad:
2299 ip6_clearpktopts(dst, -1);
2300 return (ENOBUFS);
2301 }
2302 #undef PKTOPT_EXTHDRCPY
2303
2304 struct ip6_pktopts *
ip6_copypktopts(struct ip6_pktopts * src,int canwait)2305 ip6_copypktopts(struct ip6_pktopts *src, int canwait)
2306 {
2307 int error;
2308 struct ip6_pktopts *dst;
2309
2310 dst = malloc(sizeof(*dst), M_IP6OPT, canwait);
2311 if (dst == NULL)
2312 return (NULL);
2313 ip6_initpktopts(dst);
2314
2315 if ((error = copypktopts(dst, src, canwait)) != 0) {
2316 free(dst, M_IP6OPT);
2317 return (NULL);
2318 }
2319
2320 return (dst);
2321 }
2322
2323 void
ip6_freepcbopts(struct ip6_pktopts * pktopt)2324 ip6_freepcbopts(struct ip6_pktopts *pktopt)
2325 {
2326 if (pktopt == NULL)
2327 return;
2328
2329 ip6_clearpktopts(pktopt, -1);
2330
2331 free(pktopt, M_IP6OPT);
2332 }
2333
2334 /*
2335 * Set IPv6 outgoing packet options based on advanced API.
2336 */
2337 int
ip6_setpktopts(struct mbuf * control,struct ip6_pktopts * opt,struct ip6_pktopts * stickyopt,struct ucred * cred,int uproto)2338 ip6_setpktopts(struct mbuf *control, struct ip6_pktopts *opt,
2339 struct ip6_pktopts *stickyopt, struct ucred *cred, int uproto)
2340 {
2341 struct cmsghdr *cm = 0;
2342
2343 if (control == NULL || opt == NULL)
2344 return (EINVAL);
2345
2346 ip6_initpktopts(opt);
2347 if (stickyopt) {
2348 int error;
2349
2350 /*
2351 * If stickyopt is provided, make a local copy of the options
2352 * for this particular packet, then override them by ancillary
2353 * objects.
2354 * XXX: copypktopts() does not copy the cached route to a next
2355 * hop (if any). This is not very good in terms of efficiency,
2356 * but we can allow this since this option should be rarely
2357 * used.
2358 */
2359 if ((error = copypktopts(opt, stickyopt, M_NOWAIT)) != 0)
2360 return (error);
2361 }
2362
2363 /*
2364 * XXX: Currently, we assume all the optional information is stored
2365 * in a single mbuf.
2366 */
2367 if (control->m_next)
2368 return (EINVAL);
2369
2370 for (; control->m_len > 0; control->m_data += CMSG_ALIGN(cm->cmsg_len),
2371 control->m_len -= CMSG_ALIGN(cm->cmsg_len)) {
2372 int error;
2373
2374 if (control->m_len < CMSG_LEN(0))
2375 return (EINVAL);
2376
2377 cm = mtod(control, struct cmsghdr *);
2378 if (cm->cmsg_len == 0 || cm->cmsg_len > control->m_len)
2379 return (EINVAL);
2380 if (cm->cmsg_level != IPPROTO_IPV6)
2381 continue;
2382
2383 error = ip6_setpktopt(cm->cmsg_type, CMSG_DATA(cm),
2384 cm->cmsg_len - CMSG_LEN(0), opt, cred, 0, 1, uproto);
2385 if (error)
2386 return (error);
2387 }
2388
2389 return (0);
2390 }
2391
2392 /*
2393 * Set a particular packet option, as a sticky option or an ancillary data
2394 * item. "len" can be 0 only when it's a sticky option.
2395 * We have 4 cases of combination of "sticky" and "cmsg":
2396 * "sticky=0, cmsg=0": impossible
2397 * "sticky=0, cmsg=1": RFC2292 or RFC3542 ancillary data
2398 * "sticky=1, cmsg=0": RFC3542 socket option
2399 * "sticky=1, cmsg=1": RFC2292 socket option
2400 */
2401 static int
ip6_setpktopt(int optname,u_char * buf,int len,struct ip6_pktopts * opt,struct ucred * cred,int sticky,int cmsg,int uproto)2402 ip6_setpktopt(int optname, u_char *buf, int len, struct ip6_pktopts *opt,
2403 struct ucred *cred, int sticky, int cmsg, int uproto)
2404 {
2405 int minmtupolicy, preftemp;
2406 int error;
2407
2408 if (!sticky && !cmsg) {
2409 #ifdef DIAGNOSTIC
2410 printf("ip6_setpktopt: impossible case\n");
2411 #endif
2412 return (EINVAL);
2413 }
2414
2415 /*
2416 * IPV6_2292xxx is for backward compatibility to RFC2292, and should
2417 * not be specified in the context of RFC3542. Conversely,
2418 * RFC3542 types should not be specified in the context of RFC2292.
2419 */
2420 if (!cmsg) {
2421 switch (optname) {
2422 case IPV6_2292PKTINFO:
2423 case IPV6_2292HOPLIMIT:
2424 case IPV6_2292NEXTHOP:
2425 case IPV6_2292HOPOPTS:
2426 case IPV6_2292DSTOPTS:
2427 case IPV6_2292RTHDR:
2428 case IPV6_2292PKTOPTIONS:
2429 return (ENOPROTOOPT);
2430 }
2431 }
2432 if (sticky && cmsg) {
2433 switch (optname) {
2434 case IPV6_PKTINFO:
2435 case IPV6_HOPLIMIT:
2436 case IPV6_NEXTHOP:
2437 case IPV6_HOPOPTS:
2438 case IPV6_DSTOPTS:
2439 case IPV6_RTHDRDSTOPTS:
2440 case IPV6_RTHDR:
2441 case IPV6_USE_MIN_MTU:
2442 case IPV6_DONTFRAG:
2443 case IPV6_TCLASS:
2444 case IPV6_PREFER_TEMPADDR: /* XXX: not an RFC3542 option */
2445 return (ENOPROTOOPT);
2446 }
2447 }
2448
2449 switch (optname) {
2450 case IPV6_2292PKTINFO:
2451 case IPV6_PKTINFO:
2452 {
2453 struct ifnet *ifp = NULL;
2454 struct in6_pktinfo *pktinfo;
2455
2456 if (len != sizeof(struct in6_pktinfo))
2457 return (EINVAL);
2458
2459 pktinfo = (struct in6_pktinfo *)buf;
2460
2461 /*
2462 * An application can clear any sticky IPV6_PKTINFO option by
2463 * doing a "regular" setsockopt with ipi6_addr being
2464 * in6addr_any and ipi6_ifindex being zero.
2465 * [RFC 3542, Section 6]
2466 */
2467 if (optname == IPV6_PKTINFO && opt->ip6po_pktinfo &&
2468 pktinfo->ipi6_ifindex == 0 &&
2469 IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
2470 ip6_clearpktopts(opt, optname);
2471 break;
2472 }
2473
2474 if (uproto == IPPROTO_TCP && optname == IPV6_PKTINFO &&
2475 sticky && !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
2476 return (EINVAL);
2477 }
2478
2479 /* validate the interface index if specified. */
2480 if (pktinfo->ipi6_ifindex > V_if_index ||
2481 pktinfo->ipi6_ifindex < 0) {
2482 return (ENXIO);
2483 }
2484 if (pktinfo->ipi6_ifindex) {
2485 ifp = ifnet_byindex(pktinfo->ipi6_ifindex);
2486 if (ifp == NULL)
2487 return (ENXIO);
2488 }
2489
2490 /*
2491 * We store the address anyway, and let in6_selectsrc()
2492 * validate the specified address. This is because ipi6_addr
2493 * may not have enough information about its scope zone, and
2494 * we may need additional information (such as outgoing
2495 * interface or the scope zone of a destination address) to
2496 * disambiguate the scope.
2497 * XXX: the delay of the validation may confuse the
2498 * application when it is used as a sticky option.
2499 */
2500 if (opt->ip6po_pktinfo == NULL) {
2501 opt->ip6po_pktinfo = malloc(sizeof(*pktinfo),
2502 M_IP6OPT, M_NOWAIT);
2503 if (opt->ip6po_pktinfo == NULL)
2504 return (ENOBUFS);
2505 }
2506 bcopy(pktinfo, opt->ip6po_pktinfo, sizeof(*pktinfo));
2507 break;
2508 }
2509
2510 case IPV6_2292HOPLIMIT:
2511 case IPV6_HOPLIMIT:
2512 {
2513 int *hlimp;
2514
2515 /*
2516 * RFC 3542 deprecated the usage of sticky IPV6_HOPLIMIT
2517 * to simplify the ordering among hoplimit options.
2518 */
2519 if (optname == IPV6_HOPLIMIT && sticky)
2520 return (ENOPROTOOPT);
2521
2522 if (len != sizeof(int))
2523 return (EINVAL);
2524 hlimp = (int *)buf;
2525 if (*hlimp < -1 || *hlimp > 255)
2526 return (EINVAL);
2527
2528 opt->ip6po_hlim = *hlimp;
2529 break;
2530 }
2531
2532 case IPV6_TCLASS:
2533 {
2534 int tclass;
2535
2536 if (len != sizeof(int))
2537 return (EINVAL);
2538 tclass = *(int *)buf;
2539 if (tclass < -1 || tclass > 255)
2540 return (EINVAL);
2541
2542 opt->ip6po_tclass = tclass;
2543 break;
2544 }
2545
2546 case IPV6_2292NEXTHOP:
2547 case IPV6_NEXTHOP:
2548 if (cred != NULL) {
2549 error = priv_check_cred(cred,
2550 PRIV_NETINET_SETHDROPTS, 0);
2551 if (error)
2552 return (error);
2553 }
2554
2555 if (len == 0) { /* just remove the option */
2556 ip6_clearpktopts(opt, IPV6_NEXTHOP);
2557 break;
2558 }
2559
2560 /* check if cmsg_len is large enough for sa_len */
2561 if (len < sizeof(struct sockaddr) || len < *buf)
2562 return (EINVAL);
2563
2564 switch (((struct sockaddr *)buf)->sa_family) {
2565 case AF_INET6:
2566 {
2567 struct sockaddr_in6 *sa6 = (struct sockaddr_in6 *)buf;
2568 int error;
2569
2570 if (sa6->sin6_len != sizeof(struct sockaddr_in6))
2571 return (EINVAL);
2572
2573 if (IN6_IS_ADDR_UNSPECIFIED(&sa6->sin6_addr) ||
2574 IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) {
2575 return (EINVAL);
2576 }
2577 if ((error = sa6_embedscope(sa6, V_ip6_use_defzone))
2578 != 0) {
2579 return (error);
2580 }
2581 break;
2582 }
2583 case AF_LINK: /* should eventually be supported */
2584 default:
2585 return (EAFNOSUPPORT);
2586 }
2587
2588 /* turn off the previous option, then set the new option. */
2589 ip6_clearpktopts(opt, IPV6_NEXTHOP);
2590 opt->ip6po_nexthop = malloc(*buf, M_IP6OPT, M_NOWAIT);
2591 if (opt->ip6po_nexthop == NULL)
2592 return (ENOBUFS);
2593 bcopy(buf, opt->ip6po_nexthop, *buf);
2594 break;
2595
2596 case IPV6_2292HOPOPTS:
2597 case IPV6_HOPOPTS:
2598 {
2599 struct ip6_hbh *hbh;
2600 int hbhlen;
2601
2602 /*
2603 * XXX: We don't allow a non-privileged user to set ANY HbH
2604 * options, since per-option restriction has too much
2605 * overhead.
2606 */
2607 if (cred != NULL) {
2608 error = priv_check_cred(cred,
2609 PRIV_NETINET_SETHDROPTS, 0);
2610 if (error)
2611 return (error);
2612 }
2613
2614 if (len == 0) {
2615 ip6_clearpktopts(opt, IPV6_HOPOPTS);
2616 break; /* just remove the option */
2617 }
2618
2619 /* message length validation */
2620 if (len < sizeof(struct ip6_hbh))
2621 return (EINVAL);
2622 hbh = (struct ip6_hbh *)buf;
2623 hbhlen = (hbh->ip6h_len + 1) << 3;
2624 if (len != hbhlen)
2625 return (EINVAL);
2626
2627 /* turn off the previous option, then set the new option. */
2628 ip6_clearpktopts(opt, IPV6_HOPOPTS);
2629 opt->ip6po_hbh = malloc(hbhlen, M_IP6OPT, M_NOWAIT);
2630 if (opt->ip6po_hbh == NULL)
2631 return (ENOBUFS);
2632 bcopy(hbh, opt->ip6po_hbh, hbhlen);
2633
2634 break;
2635 }
2636
2637 case IPV6_2292DSTOPTS:
2638 case IPV6_DSTOPTS:
2639 case IPV6_RTHDRDSTOPTS:
2640 {
2641 struct ip6_dest *dest, **newdest = NULL;
2642 int destlen;
2643
2644 if (cred != NULL) { /* XXX: see the comment for IPV6_HOPOPTS */
2645 error = priv_check_cred(cred,
2646 PRIV_NETINET_SETHDROPTS, 0);
2647 if (error)
2648 return (error);
2649 }
2650
2651 if (len == 0) {
2652 ip6_clearpktopts(opt, optname);
2653 break; /* just remove the option */
2654 }
2655
2656 /* message length validation */
2657 if (len < sizeof(struct ip6_dest))
2658 return (EINVAL);
2659 dest = (struct ip6_dest *)buf;
2660 destlen = (dest->ip6d_len + 1) << 3;
2661 if (len != destlen)
2662 return (EINVAL);
2663
2664 /*
2665 * Determine the position that the destination options header
2666 * should be inserted; before or after the routing header.
2667 */
2668 switch (optname) {
2669 case IPV6_2292DSTOPTS:
2670 /*
2671 * The old advacned API is ambiguous on this point.
2672 * Our approach is to determine the position based
2673 * according to the existence of a routing header.
2674 * Note, however, that this depends on the order of the
2675 * extension headers in the ancillary data; the 1st
2676 * part of the destination options header must appear
2677 * before the routing header in the ancillary data,
2678 * too.
2679 * RFC3542 solved the ambiguity by introducing
2680 * separate ancillary data or option types.
2681 */
2682 if (opt->ip6po_rthdr == NULL)
2683 newdest = &opt->ip6po_dest1;
2684 else
2685 newdest = &opt->ip6po_dest2;
2686 break;
2687 case IPV6_RTHDRDSTOPTS:
2688 newdest = &opt->ip6po_dest1;
2689 break;
2690 case IPV6_DSTOPTS:
2691 newdest = &opt->ip6po_dest2;
2692 break;
2693 }
2694
2695 /* turn off the previous option, then set the new option. */
2696 ip6_clearpktopts(opt, optname);
2697 *newdest = malloc(destlen, M_IP6OPT, M_NOWAIT);
2698 if (*newdest == NULL)
2699 return (ENOBUFS);
2700 bcopy(dest, *newdest, destlen);
2701
2702 break;
2703 }
2704
2705 case IPV6_2292RTHDR:
2706 case IPV6_RTHDR:
2707 {
2708 struct ip6_rthdr *rth;
2709 int rthlen;
2710
2711 if (len == 0) {
2712 ip6_clearpktopts(opt, IPV6_RTHDR);
2713 break; /* just remove the option */
2714 }
2715
2716 /* message length validation */
2717 if (len < sizeof(struct ip6_rthdr))
2718 return (EINVAL);
2719 rth = (struct ip6_rthdr *)buf;
2720 rthlen = (rth->ip6r_len + 1) << 3;
2721 if (len != rthlen)
2722 return (EINVAL);
2723
2724 switch (rth->ip6r_type) {
2725 case IPV6_RTHDR_TYPE_0:
2726 if (rth->ip6r_len == 0) /* must contain one addr */
2727 return (EINVAL);
2728 if (rth->ip6r_len % 2) /* length must be even */
2729 return (EINVAL);
2730 if (rth->ip6r_len / 2 != rth->ip6r_segleft)
2731 return (EINVAL);
2732 break;
2733 default:
2734 return (EINVAL); /* not supported */
2735 }
2736
2737 /* turn off the previous option */
2738 ip6_clearpktopts(opt, IPV6_RTHDR);
2739 opt->ip6po_rthdr = malloc(rthlen, M_IP6OPT, M_NOWAIT);
2740 if (opt->ip6po_rthdr == NULL)
2741 return (ENOBUFS);
2742 bcopy(rth, opt->ip6po_rthdr, rthlen);
2743
2744 break;
2745 }
2746
2747 case IPV6_USE_MIN_MTU:
2748 if (len != sizeof(int))
2749 return (EINVAL);
2750 minmtupolicy = *(int *)buf;
2751 if (minmtupolicy != IP6PO_MINMTU_MCASTONLY &&
2752 minmtupolicy != IP6PO_MINMTU_DISABLE &&
2753 minmtupolicy != IP6PO_MINMTU_ALL) {
2754 return (EINVAL);
2755 }
2756 opt->ip6po_minmtu = minmtupolicy;
2757 break;
2758
2759 case IPV6_DONTFRAG:
2760 if (len != sizeof(int))
2761 return (EINVAL);
2762
2763 if (uproto == IPPROTO_TCP || *(int *)buf == 0) {
2764 /*
2765 * we ignore this option for TCP sockets.
2766 * (RFC3542 leaves this case unspecified.)
2767 */
2768 opt->ip6po_flags &= ~IP6PO_DONTFRAG;
2769 } else
2770 opt->ip6po_flags |= IP6PO_DONTFRAG;
2771 break;
2772
2773 case IPV6_PREFER_TEMPADDR:
2774 if (len != sizeof(int))
2775 return (EINVAL);
2776 preftemp = *(int *)buf;
2777 if (preftemp != IP6PO_TEMPADDR_SYSTEM &&
2778 preftemp != IP6PO_TEMPADDR_NOTPREFER &&
2779 preftemp != IP6PO_TEMPADDR_PREFER) {
2780 return (EINVAL);
2781 }
2782 opt->ip6po_prefer_tempaddr = preftemp;
2783 break;
2784
2785 default:
2786 return (ENOPROTOOPT);
2787 } /* end of switch */
2788
2789 return (0);
2790 }
2791
2792 /*
2793 * Routine called from ip6_output() to loop back a copy of an IP6 multicast
2794 * packet to the input queue of a specified interface. Note that this
2795 * calls the output routine of the loopback "driver", but with an interface
2796 * pointer that might NOT be &loif -- easier than replicating that code here.
2797 */
2798 void
ip6_mloopback(struct ifnet * ifp,struct mbuf * m,struct sockaddr_in6 * dst)2799 ip6_mloopback(struct ifnet *ifp, struct mbuf *m, struct sockaddr_in6 *dst)
2800 {
2801 struct mbuf *copym;
2802 struct ip6_hdr *ip6;
2803
2804 copym = m_copy(m, 0, M_COPYALL);
2805 if (copym == NULL)
2806 return;
2807
2808 /*
2809 * Make sure to deep-copy IPv6 header portion in case the data
2810 * is in an mbuf cluster, so that we can safely override the IPv6
2811 * header portion later.
2812 */
2813 if ((copym->m_flags & M_EXT) != 0 ||
2814 copym->m_len < sizeof(struct ip6_hdr)) {
2815 copym = m_pullup(copym, sizeof(struct ip6_hdr));
2816 if (copym == NULL)
2817 return;
2818 }
2819 ip6 = mtod(copym, struct ip6_hdr *);
2820 /*
2821 * clear embedded scope identifiers if necessary.
2822 * in6_clearscope will touch the addresses only when necessary.
2823 */
2824 in6_clearscope(&ip6->ip6_src);
2825 in6_clearscope(&ip6->ip6_dst);
2826 if (copym->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
2827 copym->m_pkthdr.csum_flags |= CSUM_DATA_VALID_IPV6 |
2828 CSUM_PSEUDO_HDR;
2829 copym->m_pkthdr.csum_data = 0xffff;
2830 }
2831 (void)if_simloop(ifp, copym, dst->sin6_family, 0);
2832 }
2833
2834 /*
2835 * Chop IPv6 header off from the payload.
2836 */
2837 static int
ip6_splithdr(struct mbuf * m,struct ip6_exthdrs * exthdrs)2838 ip6_splithdr(struct mbuf *m, struct ip6_exthdrs *exthdrs)
2839 {
2840 struct mbuf *mh;
2841 struct ip6_hdr *ip6;
2842
2843 ip6 = mtod(m, struct ip6_hdr *);
2844 if (m->m_len > sizeof(*ip6)) {
2845 mh = m_gethdr(M_NOWAIT, MT_DATA);
2846 if (mh == NULL) {
2847 m_freem(m);
2848 return ENOBUFS;
2849 }
2850 m_move_pkthdr(mh, m);
2851 MH_ALIGN(mh, sizeof(*ip6));
2852 m->m_len -= sizeof(*ip6);
2853 m->m_data += sizeof(*ip6);
2854 mh->m_next = m;
2855 m = mh;
2856 m->m_len = sizeof(*ip6);
2857 bcopy((caddr_t)ip6, mtod(m, caddr_t), sizeof(*ip6));
2858 }
2859 exthdrs->ip6e_ip6 = m;
2860 return 0;
2861 }
2862
2863 /*
2864 * Compute IPv6 extension header length.
2865 */
2866 int
ip6_optlen(struct inpcb * in6p)2867 ip6_optlen(struct inpcb *in6p)
2868 {
2869 int len;
2870
2871 if (!in6p->in6p_outputopts)
2872 return 0;
2873
2874 len = 0;
2875 #define elen(x) \
2876 (((struct ip6_ext *)(x)) ? (((struct ip6_ext *)(x))->ip6e_len + 1) << 3 : 0)
2877
2878 len += elen(in6p->in6p_outputopts->ip6po_hbh);
2879 if (in6p->in6p_outputopts->ip6po_rthdr)
2880 /* dest1 is valid with rthdr only */
2881 len += elen(in6p->in6p_outputopts->ip6po_dest1);
2882 len += elen(in6p->in6p_outputopts->ip6po_rthdr);
2883 len += elen(in6p->in6p_outputopts->ip6po_dest2);
2884 return len;
2885 #undef elen
2886 }
2887