kernel tree reorganization stage 1: Major cvs repository work (not logged as
[dragonfly.git] / sys / netinet6 / ip6_output.c
1 /*      $FreeBSD: src/sys/netinet6/ip6_output.c,v 1.13.2.18 2003/01/24 05:11:35 sam Exp $       */
2 /*      $DragonFly: src/sys/netinet6/ip6_output.c,v 1.7 2003/08/07 21:54:33 dillon Exp $        */
3 /*      $KAME: ip6_output.c,v 1.279 2002/01/26 06:12:30 jinmei Exp $    */
4
5 /*
6  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. Neither the name of the project nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33
34 /*
35  * Copyright (c) 1982, 1986, 1988, 1990, 1993
36  *      The Regents of the University of California.  All rights reserved.
37  *
38  * Redistribution and use in source and binary forms, with or without
39  * modification, are permitted provided that the following conditions
40  * are met:
41  * 1. Redistributions of source code must retain the above copyright
42  *    notice, this list of conditions and the following disclaimer.
43  * 2. Redistributions in binary form must reproduce the above copyright
44  *    notice, this list of conditions and the following disclaimer in the
45  *    documentation and/or other materials provided with the distribution.
46  * 3. All advertising materials mentioning features or use of this software
47  *    must display the following acknowledgement:
48  *      This product includes software developed by the University of
49  *      California, Berkeley and its contributors.
50  * 4. Neither the name of the University nor the names of its contributors
51  *    may be used to endorse or promote products derived from this software
52  *    without specific prior written permission.
53  *
54  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
55  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
56  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
57  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
58  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
59  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
60  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
61  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
62  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
63  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
64  * SUCH DAMAGE.
65  *
66  *      @(#)ip_output.c 8.3 (Berkeley) 1/21/94
67  */
68
69 #include "opt_ip6fw.h"
70 #include "opt_inet.h"
71 #include "opt_inet6.h"
72 #include "opt_ipsec.h"
73
74 #include <sys/param.h>
75 #include <sys/malloc.h>
76 #include <sys/mbuf.h>
77 #include <sys/errno.h>
78 #include <sys/protosw.h>
79 #include <sys/socket.h>
80 #include <sys/socketvar.h>
81 #include <sys/systm.h>
82 #include <sys/kernel.h>
83 #include <sys/proc.h>
84
85 #include <net/if.h>
86 #include <net/route.h>
87
88 #include <netinet/in.h>
89 #include <netinet/in_var.h>
90 #include <netinet6/in6_var.h>
91 #include <netinet/ip6.h>
92 #include <netinet/icmp6.h>
93 #include <netinet6/ip6_var.h>
94 #include <netinet/in_pcb.h>
95 #include <netinet6/nd6.h>
96
97 #ifdef IPSEC
98 #include <netinet6/ipsec.h>
99 #ifdef INET6
100 #include <netinet6/ipsec6.h>
101 #endif
102 #include <netproto/key/key.h>
103 #endif /* IPSEC */
104
105 #ifdef FAST_IPSEC
106 #include "ipsec.h"
107 #include "ipsec6.h"
108 #include <netipsec/key.h>
109 #endif /* FAST_IPSEC */
110
111 #include <net/ip6fw/ip6_fw.h>
112
113 #include <net/net_osdep.h>
114
115 struct ip;
116 extern int (*fr_checkp) __P((struct ip *, int, struct ifnet *, int, struct mbuf **));
117
118 static MALLOC_DEFINE(M_IPMOPTS, "ip6_moptions", "internet multicast options");
119
120 struct ip6_exthdrs {
121         struct mbuf *ip6e_ip6;
122         struct mbuf *ip6e_hbh;
123         struct mbuf *ip6e_dest1;
124         struct mbuf *ip6e_rthdr;
125         struct mbuf *ip6e_dest2;
126 };
127
128 static int ip6_pcbopts __P((struct ip6_pktopts **, struct mbuf *,
129                             struct socket *, struct sockopt *sopt));
130 static int ip6_setmoptions __P((int, struct ip6_moptions **, struct mbuf *));
131 static int ip6_getmoptions __P((int, struct ip6_moptions *, struct mbuf **));
132 static int ip6_copyexthdr __P((struct mbuf **, caddr_t, int));
133 static int ip6_insertfraghdr __P((struct mbuf *, struct mbuf *, int,
134                                   struct ip6_frag **));
135 static int ip6_insert_jumboopt __P((struct ip6_exthdrs *, u_int32_t));
136 static int ip6_splithdr __P((struct mbuf *, struct ip6_exthdrs *));
137
138 /*
139  * IP6 output. The packet in mbuf chain m contains a skeletal IP6
140  * header (with pri, len, nxt, hlim, src, dst).
141  * This function may modify ver and hlim only.
142  * The mbuf chain containing the packet will be freed.
143  * The mbuf opt, if present, will not be freed.
144  *
145  * type of "mtu": rt_rmx.rmx_mtu is u_long, ifnet.ifr_mtu is int, and
146  * nd_ifinfo.linkmtu is u_int32_t.  so we use u_long to hold largest one,
147  * which is rt_rmx.rmx_mtu.
148  */
149 int
150 ip6_output(m0, opt, ro, flags, im6o, ifpp, inp)
151         struct mbuf *m0;
152         struct ip6_pktopts *opt;
153         struct route_in6 *ro;
154         int flags;
155         struct ip6_moptions *im6o;
156         struct ifnet **ifpp;            /* XXX: just for statistics */
157         struct inpcb *inp;
158 {
159         struct ip6_hdr *ip6, *mhip6;
160         struct ifnet *ifp, *origifp;
161         struct mbuf *m = m0;
162         int hlen, tlen, len, off;
163         struct route_in6 ip6route;
164         struct sockaddr_in6 *dst;
165         int error = 0;
166         struct in6_ifaddr *ia = NULL;
167         u_long mtu;
168         u_int32_t optlen = 0, plen = 0, unfragpartlen = 0;
169         struct ip6_exthdrs exthdrs;
170         struct in6_addr finaldst;
171         struct route_in6 *ro_pmtu = NULL;
172         int hdrsplit = 0;
173         int needipsec = 0;
174 #ifdef IPSEC
175         int needipsectun = 0;
176         struct secpolicy *sp = NULL;
177         struct socket *so = inp ? inp->inp_socket : NULL;
178
179         ip6 = mtod(m, struct ip6_hdr *);
180 #endif /* IPSEC */
181 #ifdef FAST_IPSEC
182         int needipsectun = 0;
183         struct secpolicy *sp = NULL;
184
185         ip6 = mtod(m, struct ip6_hdr *);
186 #endif /* FAST_IPSEC */
187
188 #define MAKE_EXTHDR(hp, mp)                                             \
189     do {                                                                \
190         if (hp) {                                                       \
191                 struct ip6_ext *eh = (struct ip6_ext *)(hp);            \
192                 error = ip6_copyexthdr((mp), (caddr_t)(hp),             \
193                                        ((eh)->ip6e_len + 1) << 3);      \
194                 if (error)                                              \
195                         goto freehdrs;                                  \
196         }                                                               \
197     } while (0)
198         
199         bzero(&exthdrs, sizeof(exthdrs));
200         
201         if (opt) {
202                 /* Hop-by-Hop options header */
203                 MAKE_EXTHDR(opt->ip6po_hbh, &exthdrs.ip6e_hbh);
204                 /* Destination options header(1st part) */
205                 MAKE_EXTHDR(opt->ip6po_dest1, &exthdrs.ip6e_dest1);
206                 /* Routing header */
207                 MAKE_EXTHDR(opt->ip6po_rthdr, &exthdrs.ip6e_rthdr);
208                 /* Destination options header(2nd part) */
209                 MAKE_EXTHDR(opt->ip6po_dest2, &exthdrs.ip6e_dest2);
210         }
211
212 #ifdef IPSEC
213         /* get a security policy for this packet */
214         if (so == NULL)
215                 sp = ipsec6_getpolicybyaddr(m, IPSEC_DIR_OUTBOUND, 0, &error);
216         else
217                 sp = ipsec6_getpolicybysock(m, IPSEC_DIR_OUTBOUND, so, &error);
218
219         if (sp == NULL) {
220                 ipsec6stat.out_inval++;
221                 goto freehdrs;
222         }
223
224         error = 0;
225
226         /* check policy */
227         switch (sp->policy) {
228         case IPSEC_POLICY_DISCARD:
229                 /*
230                  * This packet is just discarded.
231                  */
232                 ipsec6stat.out_polvio++;
233                 goto freehdrs;
234
235         case IPSEC_POLICY_BYPASS:
236         case IPSEC_POLICY_NONE:
237                 /* no need to do IPsec. */
238                 needipsec = 0;
239                 break;
240         
241         case IPSEC_POLICY_IPSEC:
242                 if (sp->req == NULL) {
243                         /* acquire a policy */
244                         error = key_spdacquire(sp);
245                         goto freehdrs;
246                 }
247                 needipsec = 1;
248                 break;
249
250         case IPSEC_POLICY_ENTRUST:
251         default:
252                 printf("ip6_output: Invalid policy found. %d\n", sp->policy);
253         }
254 #endif /* IPSEC */
255 #ifdef FAST_IPSEC
256         /* get a security policy for this packet */
257         if (inp == NULL)
258                 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_OUTBOUND, 0, &error);
259         else
260                 sp = ipsec_getpolicybysock(m, IPSEC_DIR_OUTBOUND, inp, &error);
261
262         if (sp == NULL) {
263                 newipsecstat.ips_out_inval++;
264                 goto freehdrs;
265         }
266
267         error = 0;
268
269         /* check policy */
270         switch (sp->policy) {
271         case IPSEC_POLICY_DISCARD:
272                 /*
273                  * This packet is just discarded.
274                  */
275                 newipsecstat.ips_out_polvio++;
276                 goto freehdrs;
277
278         case IPSEC_POLICY_BYPASS:
279         case IPSEC_POLICY_NONE:
280                 /* no need to do IPsec. */
281                 needipsec = 0;
282                 break;
283         
284         case IPSEC_POLICY_IPSEC:
285                 if (sp->req == NULL) {
286                         /* acquire a policy */
287                         error = key_spdacquire(sp);
288                         goto freehdrs;
289                 }
290                 needipsec = 1;
291                 break;
292
293         case IPSEC_POLICY_ENTRUST:
294         default:
295                 printf("ip6_output: Invalid policy found. %d\n", sp->policy);
296         }
297 #endif /* FAST_IPSEC */
298
299         /*
300          * Calculate the total length of the extension header chain.
301          * Keep the length of the unfragmentable part for fragmentation.
302          */
303         optlen = 0;
304         if (exthdrs.ip6e_hbh) optlen += exthdrs.ip6e_hbh->m_len;
305         if (exthdrs.ip6e_dest1) optlen += exthdrs.ip6e_dest1->m_len;
306         if (exthdrs.ip6e_rthdr) optlen += exthdrs.ip6e_rthdr->m_len;
307         unfragpartlen = optlen + sizeof(struct ip6_hdr);
308         /* NOTE: we don't add AH/ESP length here. do that later. */
309         if (exthdrs.ip6e_dest2) optlen += exthdrs.ip6e_dest2->m_len;
310
311         /*
312          * If we need IPsec, or there is at least one extension header,
313          * separate IP6 header from the payload.
314          */
315         if ((needipsec || optlen) && !hdrsplit) {
316                 if ((error = ip6_splithdr(m, &exthdrs)) != 0) {
317                         m = NULL;
318                         goto freehdrs;
319                 }
320                 m = exthdrs.ip6e_ip6;
321                 hdrsplit++;
322         }
323
324         /* adjust pointer */
325         ip6 = mtod(m, struct ip6_hdr *);
326
327         /* adjust mbuf packet header length */
328         m->m_pkthdr.len += optlen;
329         plen = m->m_pkthdr.len - sizeof(*ip6);
330
331         /* If this is a jumbo payload, insert a jumbo payload option. */
332         if (plen > IPV6_MAXPACKET) {
333                 if (!hdrsplit) {
334                         if ((error = ip6_splithdr(m, &exthdrs)) != 0) {
335                                 m = NULL;
336                                 goto freehdrs;
337                         }
338                         m = exthdrs.ip6e_ip6;
339                         hdrsplit++;
340                 }
341                 /* adjust pointer */
342                 ip6 = mtod(m, struct ip6_hdr *);
343                 if ((error = ip6_insert_jumboopt(&exthdrs, plen)) != 0)
344                         goto freehdrs;
345                 ip6->ip6_plen = 0;
346         } else
347                 ip6->ip6_plen = htons(plen);
348
349         /*
350          * Concatenate headers and fill in next header fields.
351          * Here we have, on "m"
352          *      IPv6 payload
353          * and we insert headers accordingly.  Finally, we should be getting:
354          *      IPv6 hbh dest1 rthdr ah* [esp* dest2 payload]
355          *
356          * during the header composing process, "m" points to IPv6 header.
357          * "mprev" points to an extension header prior to esp.
358          */
359         {
360                 u_char *nexthdrp = &ip6->ip6_nxt;
361                 struct mbuf *mprev = m;
362
363                 /*
364                  * we treat dest2 specially.  this makes IPsec processing
365                  * much easier.  the goal here is to make mprev point the
366                  * mbuf prior to dest2.
367                  *
368                  * result: IPv6 dest2 payload
369                  * m and mprev will point to IPv6 header.
370                  */
371                 if (exthdrs.ip6e_dest2) {
372                         if (!hdrsplit)
373                                 panic("assumption failed: hdr not split");
374                         exthdrs.ip6e_dest2->m_next = m->m_next;
375                         m->m_next = exthdrs.ip6e_dest2;
376                         *mtod(exthdrs.ip6e_dest2, u_char *) = ip6->ip6_nxt;
377                         ip6->ip6_nxt = IPPROTO_DSTOPTS;
378                 }
379
380 #define MAKE_CHAIN(m, mp, p, i)\
381     do {\
382         if (m) {\
383                 if (!hdrsplit) \
384                         panic("assumption failed: hdr not split"); \
385                 *mtod((m), u_char *) = *(p);\
386                 *(p) = (i);\
387                 p = mtod((m), u_char *);\
388                 (m)->m_next = (mp)->m_next;\
389                 (mp)->m_next = (m);\
390                 (mp) = (m);\
391         }\
392     } while (0)
393                 /*
394                  * result: IPv6 hbh dest1 rthdr dest2 payload
395                  * m will point to IPv6 header.  mprev will point to the
396                  * extension header prior to dest2 (rthdr in the above case).
397                  */
398                 MAKE_CHAIN(exthdrs.ip6e_hbh, mprev,
399                            nexthdrp, IPPROTO_HOPOPTS);
400                 MAKE_CHAIN(exthdrs.ip6e_dest1, mprev,
401                            nexthdrp, IPPROTO_DSTOPTS);
402                 MAKE_CHAIN(exthdrs.ip6e_rthdr, mprev,
403                            nexthdrp, IPPROTO_ROUTING);
404
405 #if defined(IPSEC) || defined(FAST_IPSEC)
406                 if (!needipsec)
407                         goto skip_ipsec2;
408
409                 /*
410                  * pointers after IPsec headers are not valid any more.
411                  * other pointers need a great care too.
412                  * (IPsec routines should not mangle mbufs prior to AH/ESP)
413                  */
414                 exthdrs.ip6e_dest2 = NULL;
415
416             {
417                 struct ip6_rthdr *rh = NULL;
418                 int segleft_org = 0;
419                 struct ipsec_output_state state;
420
421                 if (exthdrs.ip6e_rthdr) {
422                         rh = mtod(exthdrs.ip6e_rthdr, struct ip6_rthdr *);
423                         segleft_org = rh->ip6r_segleft;
424                         rh->ip6r_segleft = 0;
425                 }
426
427                 bzero(&state, sizeof(state));
428                 state.m = m;
429                 error = ipsec6_output_trans(&state, nexthdrp, mprev, sp, flags,
430                         &needipsectun);
431                 m = state.m;
432                 if (error) {
433                         /* mbuf is already reclaimed in ipsec6_output_trans. */
434                         m = NULL;
435                         switch (error) {
436                         case EHOSTUNREACH:
437                         case ENETUNREACH:
438                         case EMSGSIZE:
439                         case ENOBUFS:
440                         case ENOMEM:
441                                 break;
442                         default:
443                                 printf("ip6_output (ipsec): error code %d\n", error);
444                                 /* fall through */
445                         case ENOENT:
446                                 /* don't show these error codes to the user */
447                                 error = 0;
448                                 break;
449                         }
450                         goto bad;
451                 }
452                 if (exthdrs.ip6e_rthdr) {
453                         /* ah6_output doesn't modify mbuf chain */
454                         rh->ip6r_segleft = segleft_org;
455                 }
456             }
457 skip_ipsec2:;
458 #endif
459         }
460
461         /*
462          * If there is a routing header, replace destination address field
463          * with the first hop of the routing header.
464          */
465         if (exthdrs.ip6e_rthdr) {
466                 struct ip6_rthdr *rh =
467                         (struct ip6_rthdr *)(mtod(exthdrs.ip6e_rthdr,
468                                                   struct ip6_rthdr *));
469                 struct ip6_rthdr0 *rh0;
470
471                 finaldst = ip6->ip6_dst;
472                 switch (rh->ip6r_type) {
473                 case IPV6_RTHDR_TYPE_0:
474                          rh0 = (struct ip6_rthdr0 *)rh;
475                          ip6->ip6_dst = rh0->ip6r0_addr[0];
476                          bcopy((caddr_t)&rh0->ip6r0_addr[1],
477                                (caddr_t)&rh0->ip6r0_addr[0],
478                                sizeof(struct in6_addr)*(rh0->ip6r0_segleft - 1)
479                                  );
480                          rh0->ip6r0_addr[rh0->ip6r0_segleft - 1] = finaldst;
481                          break;
482                 default:        /* is it possible? */
483                          error = EINVAL;
484                          goto bad;
485                 }
486         }
487
488         /* Source address validation */
489         if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) &&
490             (flags & IPV6_DADOUTPUT) == 0) {
491                 error = EOPNOTSUPP;
492                 ip6stat.ip6s_badscope++;
493                 goto bad;
494         }
495         if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src)) {
496                 error = EOPNOTSUPP;
497                 ip6stat.ip6s_badscope++;
498                 goto bad;
499         }
500
501         ip6stat.ip6s_localout++;
502
503         /*
504          * Route packet.
505          */
506         if (ro == 0) {
507                 ro = &ip6route;
508                 bzero((caddr_t)ro, sizeof(*ro));
509         }
510         ro_pmtu = ro;
511         if (opt && opt->ip6po_rthdr)
512                 ro = &opt->ip6po_route;
513         dst = (struct sockaddr_in6 *)&ro->ro_dst;
514         /*
515          * If there is a cached route,
516          * check that it is to the same destination
517          * and is still up. If not, free it and try again.
518          */
519         if (ro->ro_rt && ((ro->ro_rt->rt_flags & RTF_UP) == 0 ||
520                          dst->sin6_family != AF_INET6 ||
521                          !IN6_ARE_ADDR_EQUAL(&dst->sin6_addr, &ip6->ip6_dst))) {
522                 RTFREE(ro->ro_rt);
523                 ro->ro_rt = (struct rtentry *)0;
524         }
525         if (ro->ro_rt == 0) {
526                 bzero(dst, sizeof(*dst));
527                 dst->sin6_family = AF_INET6;
528                 dst->sin6_len = sizeof(struct sockaddr_in6);
529                 dst->sin6_addr = ip6->ip6_dst;
530 #ifdef SCOPEDROUTING
531                 /* XXX: sin6_scope_id should already be fixed at this point */
532                 if (IN6_IS_SCOPE_LINKLOCAL(&dst->sin6_addr))
533                         dst->sin6_scope_id = ntohs(dst->sin6_addr.s6_addr16[1]);
534 #endif
535         }
536 #if defined(IPSEC) || defined(FAST_IPSEC)
537         if (needipsec && needipsectun) {
538                 struct ipsec_output_state state;
539
540                 /*
541                  * All the extension headers will become inaccessible
542                  * (since they can be encrypted).
543                  * Don't panic, we need no more updates to extension headers
544                  * on inner IPv6 packet (since they are now encapsulated).
545                  *
546                  * IPv6 [ESP|AH] IPv6 [extension headers] payload
547                  */
548                 bzero(&exthdrs, sizeof(exthdrs));
549                 exthdrs.ip6e_ip6 = m;
550
551                 bzero(&state, sizeof(state));
552                 state.m = m;
553                 state.ro = (struct route *)ro;
554                 state.dst = (struct sockaddr *)dst;
555
556                 error = ipsec6_output_tunnel(&state, sp, flags);
557
558                 m = state.m;
559                 ro = (struct route_in6 *)state.ro;
560                 dst = (struct sockaddr_in6 *)state.dst;
561                 if (error) {
562                         /* mbuf is already reclaimed in ipsec6_output_tunnel. */
563                         m0 = m = NULL;
564                         m = NULL;
565                         switch (error) {
566                         case EHOSTUNREACH:
567                         case ENETUNREACH:
568                         case EMSGSIZE:
569                         case ENOBUFS:
570                         case ENOMEM:
571                                 break;
572                         default:
573                                 printf("ip6_output (ipsec): error code %d\n", error);
574                                 /* fall through */
575                         case ENOENT:
576                                 /* don't show these error codes to the user */
577                                 error = 0;
578                                 break;
579                         }
580                         goto bad;
581                 }
582
583                 exthdrs.ip6e_ip6 = m;
584         }
585 #endif /* IPSEC */
586
587         if (!IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
588                 /* Unicast */
589
590 #define ifatoia6(ifa)   ((struct in6_ifaddr *)(ifa))
591 #define sin6tosa(sin6)  ((struct sockaddr *)(sin6))
592                 /* xxx
593                  * interface selection comes here
594                  * if an interface is specified from an upper layer,
595                  * ifp must point it.
596                  */
597                 if (ro->ro_rt == 0) {
598                         /*
599                          * non-bsdi always clone routes, if parent is
600                          * PRF_CLONING.
601                          */
602                         rtalloc((struct route *)ro);
603                 }
604                 if (ro->ro_rt == 0) {
605                         ip6stat.ip6s_noroute++;
606                         error = EHOSTUNREACH;
607                         /* XXX in6_ifstat_inc(ifp, ifs6_out_discard); */
608                         goto bad;
609                 }
610                 ia = ifatoia6(ro->ro_rt->rt_ifa);
611                 ifp = ro->ro_rt->rt_ifp;
612                 ro->ro_rt->rt_use++;
613                 if (ro->ro_rt->rt_flags & RTF_GATEWAY)
614                         dst = (struct sockaddr_in6 *)ro->ro_rt->rt_gateway;
615                 m->m_flags &= ~(M_BCAST | M_MCAST);     /* just in case */
616
617                 in6_ifstat_inc(ifp, ifs6_out_request);
618
619                 /*
620                  * Check if the outgoing interface conflicts with
621                  * the interface specified by ifi6_ifindex (if specified).
622                  * Note that loopback interface is always okay.
623                  * (this may happen when we are sending a packet to one of
624                  *  our own addresses.)
625                  */
626                 if (opt && opt->ip6po_pktinfo
627                  && opt->ip6po_pktinfo->ipi6_ifindex) {
628                         if (!(ifp->if_flags & IFF_LOOPBACK)
629                          && ifp->if_index != opt->ip6po_pktinfo->ipi6_ifindex) {
630                                 ip6stat.ip6s_noroute++;
631                                 in6_ifstat_inc(ifp, ifs6_out_discard);
632                                 error = EHOSTUNREACH;
633                                 goto bad;
634                         }
635                 }
636
637                 if (opt && opt->ip6po_hlim != -1)
638                         ip6->ip6_hlim = opt->ip6po_hlim & 0xff;
639         } else {
640                 /* Multicast */
641                 struct  in6_multi *in6m;
642
643                 m->m_flags = (m->m_flags & ~M_BCAST) | M_MCAST;
644
645                 /*
646                  * See if the caller provided any multicast options
647                  */
648                 ifp = NULL;
649                 if (im6o != NULL) {
650                         ip6->ip6_hlim = im6o->im6o_multicast_hlim;
651                         if (im6o->im6o_multicast_ifp != NULL)
652                                 ifp = im6o->im6o_multicast_ifp;
653                 } else
654                         ip6->ip6_hlim = ip6_defmcasthlim;
655
656                 /*
657                  * See if the caller provided the outgoing interface
658                  * as an ancillary data.
659                  * Boundary check for ifindex is assumed to be already done.
660                  */
661                 if (opt && opt->ip6po_pktinfo && opt->ip6po_pktinfo->ipi6_ifindex)
662                         ifp = ifindex2ifnet[opt->ip6po_pktinfo->ipi6_ifindex];
663
664                 /*
665                  * If the destination is a node-local scope multicast,
666                  * the packet should be loop-backed only.
667                  */
668                 if (IN6_IS_ADDR_MC_NODELOCAL(&ip6->ip6_dst)) {
669                         /*
670                          * If the outgoing interface is already specified,
671                          * it should be a loopback interface.
672                          */
673                         if (ifp && (ifp->if_flags & IFF_LOOPBACK) == 0) {
674                                 ip6stat.ip6s_badscope++;
675                                 error = ENETUNREACH; /* XXX: better error? */
676                                 /* XXX correct ifp? */
677                                 in6_ifstat_inc(ifp, ifs6_out_discard);
678                                 goto bad;
679                         } else {
680                                 ifp = &loif[0];
681                         }
682                 }
683
684                 if (opt && opt->ip6po_hlim != -1)
685                         ip6->ip6_hlim = opt->ip6po_hlim & 0xff;
686
687                 /*
688                  * If caller did not provide an interface lookup a
689                  * default in the routing table.  This is either a
690                  * default for the speicfied group (i.e. a host
691                  * route), or a multicast default (a route for the
692                  * ``net'' ff00::/8).
693                  */
694                 if (ifp == NULL) {
695                         if (ro->ro_rt == 0) {
696                                 ro->ro_rt = rtalloc1((struct sockaddr *)
697                                                 &ro->ro_dst, 0, 0UL);
698                         }
699                         if (ro->ro_rt == 0) {
700                                 ip6stat.ip6s_noroute++;
701                                 error = EHOSTUNREACH;
702                                 /* XXX in6_ifstat_inc(ifp, ifs6_out_discard) */
703                                 goto bad;
704                         }
705                         ia = ifatoia6(ro->ro_rt->rt_ifa);
706                         ifp = ro->ro_rt->rt_ifp;
707                         ro->ro_rt->rt_use++;
708                 }
709
710                 if ((flags & IPV6_FORWARDING) == 0)
711                         in6_ifstat_inc(ifp, ifs6_out_request);
712                 in6_ifstat_inc(ifp, ifs6_out_mcast);
713
714                 /*
715                  * Confirm that the outgoing interface supports multicast.
716                  */
717                 if ((ifp->if_flags & IFF_MULTICAST) == 0) {
718                         ip6stat.ip6s_noroute++;
719                         in6_ifstat_inc(ifp, ifs6_out_discard);
720                         error = ENETUNREACH;
721                         goto bad;
722                 }
723                 IN6_LOOKUP_MULTI(ip6->ip6_dst, ifp, in6m);
724                 if (in6m != NULL &&
725                    (im6o == NULL || im6o->im6o_multicast_loop)) {
726                         /*
727                          * If we belong to the destination multicast group
728                          * on the outgoing interface, and the caller did not
729                          * forbid loopback, loop back a copy.
730                          */
731                         ip6_mloopback(ifp, m, dst);
732                 } else {
733                         /*
734                          * If we are acting as a multicast router, perform
735                          * multicast forwarding as if the packet had just
736                          * arrived on the interface to which we are about
737                          * to send.  The multicast forwarding function
738                          * recursively calls this function, using the
739                          * IPV6_FORWARDING flag to prevent infinite recursion.
740                          *
741                          * Multicasts that are looped back by ip6_mloopback(),
742                          * above, will be forwarded by the ip6_input() routine,
743                          * if necessary.
744                          */
745                         if (ip6_mrouter && (flags & IPV6_FORWARDING) == 0) {
746                                 if (ip6_mforward(ip6, ifp, m) != 0) {
747                                         m_freem(m);
748                                         goto done;
749                                 }
750                         }
751                 }
752                 /*
753                  * Multicasts with a hoplimit of zero may be looped back,
754                  * above, but must not be transmitted on a network.
755                  * Also, multicasts addressed to the loopback interface
756                  * are not sent -- the above call to ip6_mloopback() will
757                  * loop back a copy if this host actually belongs to the
758                  * destination group on the loopback interface.
759                  */
760                 if (ip6->ip6_hlim == 0 || (ifp->if_flags & IFF_LOOPBACK)) {
761                         m_freem(m);
762                         goto done;
763                 }
764         }
765
766         /*
767          * Fill the outgoing inteface to tell the upper layer
768          * to increment per-interface statistics.
769          */
770         if (ifpp)
771                 *ifpp = ifp;
772
773         /*
774          * Determine path MTU.
775          */
776         if (ro_pmtu != ro) {
777                 /* The first hop and the final destination may differ. */
778                 struct sockaddr_in6 *sin6_fin =
779                         (struct sockaddr_in6 *)&ro_pmtu->ro_dst;
780                 if (ro_pmtu->ro_rt && ((ro->ro_rt->rt_flags & RTF_UP) == 0 ||
781                                        !IN6_ARE_ADDR_EQUAL(&sin6_fin->sin6_addr,
782                                                            &finaldst))) {
783                         RTFREE(ro_pmtu->ro_rt);
784                         ro_pmtu->ro_rt = (struct rtentry *)0;
785                 }
786                 if (ro_pmtu->ro_rt == 0) {
787                         bzero(sin6_fin, sizeof(*sin6_fin));
788                         sin6_fin->sin6_family = AF_INET6;
789                         sin6_fin->sin6_len = sizeof(struct sockaddr_in6);
790                         sin6_fin->sin6_addr = finaldst;
791
792                         rtalloc((struct route *)ro_pmtu);
793                 }
794         }
795         if (ro_pmtu->ro_rt != NULL) {
796                 u_int32_t ifmtu = nd_ifinfo[ifp->if_index].linkmtu;
797
798                 mtu = ro_pmtu->ro_rt->rt_rmx.rmx_mtu;
799                 if (mtu > ifmtu || mtu == 0) {
800                         /*
801                          * The MTU on the route is larger than the MTU on
802                          * the interface!  This shouldn't happen, unless the
803                          * MTU of the interface has been changed after the
804                          * interface was brought up.  Change the MTU in the
805                          * route to match the interface MTU (as long as the
806                          * field isn't locked).
807                          *
808                          * if MTU on the route is 0, we need to fix the MTU.
809                          * this case happens with path MTU discovery timeouts.
810                          */
811                          mtu = ifmtu;
812                          if ((ro_pmtu->ro_rt->rt_rmx.rmx_locks & RTV_MTU) == 0)
813                                  ro_pmtu->ro_rt->rt_rmx.rmx_mtu = mtu; /* XXX */
814                 }
815         } else {
816                 mtu = nd_ifinfo[ifp->if_index].linkmtu;
817         }
818
819         /*
820          * advanced API (IPV6_USE_MIN_MTU) overrides mtu setting
821          */
822         if ((flags & IPV6_MINMTU) != 0 && mtu > IPV6_MMTU)
823                 mtu = IPV6_MMTU;
824
825         /* Fake scoped addresses */
826         if ((ifp->if_flags & IFF_LOOPBACK) != 0) {
827                 /*
828                  * If source or destination address is a scoped address, and
829                  * the packet is going to be sent to a loopback interface,
830                  * we should keep the original interface.
831                  */
832
833                 /*
834                  * XXX: this is a very experimental and temporary solution.
835                  * We eventually have sockaddr_in6 and use the sin6_scope_id
836                  * field of the structure here.
837                  * We rely on the consistency between two scope zone ids
838                  * of source and destination, which should already be assured.
839                  * Larger scopes than link will be supported in the future. 
840                  */
841                 origifp = NULL;
842                 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src))
843                         origifp = ifindex2ifnet[ntohs(ip6->ip6_src.s6_addr16[1])];
844                 else if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst))
845                         origifp = ifindex2ifnet[ntohs(ip6->ip6_dst.s6_addr16[1])];
846                 /*
847                  * XXX: origifp can be NULL even in those two cases above.
848                  * For example, if we remove the (only) link-local address
849                  * from the loopback interface, and try to send a link-local
850                  * address without link-id information.  Then the source
851                  * address is ::1, and the destination address is the
852                  * link-local address with its s6_addr16[1] being zero.
853                  * What is worse, if the packet goes to the loopback interface
854                  * by a default rejected route, the null pointer would be
855                  * passed to looutput, and the kernel would hang.
856                  * The following last resort would prevent such disaster.
857                  */
858                 if (origifp == NULL)
859                         origifp = ifp;
860         }
861         else
862                 origifp = ifp;
863 #ifndef SCOPEDROUTING
864         /*
865          * clear embedded scope identifiers if necessary.
866          * in6_clearscope will touch the addresses only when necessary.
867          */
868         in6_clearscope(&ip6->ip6_src);
869         in6_clearscope(&ip6->ip6_dst);
870 #endif
871
872         /*
873          * Check with the firewall...
874          */
875         if (ip6_fw_enable && ip6_fw_chk_ptr) {
876                 u_short port = 0;
877                 m->m_pkthdr.rcvif = NULL;       /* XXX */
878                 /* If ipfw says divert, we have to just drop packet */
879                 if ((*ip6_fw_chk_ptr)(&ip6, ifp, &port, &m)) {
880                         m_freem(m);
881                         goto done;
882                 }
883                 if (!m) {
884                         error = EACCES;
885                         goto done;
886                 }
887         }
888
889         /*
890          * If the outgoing packet contains a hop-by-hop options header,
891          * it must be examined and processed even by the source node.
892          * (RFC 2460, section 4.)
893          */
894         if (exthdrs.ip6e_hbh) {
895                 struct ip6_hbh *hbh = mtod(exthdrs.ip6e_hbh, struct ip6_hbh *);
896                 u_int32_t dummy1; /* XXX unused */
897                 u_int32_t dummy2; /* XXX unused */
898
899 #ifdef DIAGNOSTIC
900                 if ((hbh->ip6h_len + 1) << 3 > exthdrs.ip6e_hbh->m_len)
901                         panic("ip6e_hbh is not continuous");
902 #endif
903                 /*
904                  *  XXX: if we have to send an ICMPv6 error to the sender,
905                  *       we need the M_LOOP flag since icmp6_error() expects
906                  *       the IPv6 and the hop-by-hop options header are
907                  *       continuous unless the flag is set.
908                  */
909                 m->m_flags |= M_LOOP;
910                 m->m_pkthdr.rcvif = ifp;
911                 if (ip6_process_hopopts(m,
912                                         (u_int8_t *)(hbh + 1),
913                                         ((hbh->ip6h_len + 1) << 3) -
914                                         sizeof(struct ip6_hbh),
915                                         &dummy1, &dummy2) < 0) {
916                         /* m was already freed at this point */
917                         error = EINVAL;/* better error? */
918                         goto done;
919                 }
920                 m->m_flags &= ~M_LOOP; /* XXX */
921                 m->m_pkthdr.rcvif = NULL;
922         }
923
924         /*
925          * Check if we want to allow this packet to be processed.
926          * Consider it to be bad if not.
927          */
928         if (fr_checkp) {
929                 struct  mbuf    *m1 = m;
930
931                 if ((*fr_checkp)((struct ip *)ip6, sizeof(*ip6), ifp, 1, &m1))
932                         goto done;
933                 m = m1;
934                 if (m == NULL)
935                         goto done;
936                 ip6 = mtod(m, struct ip6_hdr *);
937         }
938
939         /*
940          * Send the packet to the outgoing interface.
941          * If necessary, do IPv6 fragmentation before sending.
942          */
943         tlen = m->m_pkthdr.len;
944         if (tlen <= mtu
945 #ifdef notyet
946             /*
947              * On any link that cannot convey a 1280-octet packet in one piece,
948              * link-specific fragmentation and reassembly must be provided at
949              * a layer below IPv6. [RFC 2460, sec.5]
950              * Thus if the interface has ability of link-level fragmentation,
951              * we can just send the packet even if the packet size is
952              * larger than the link's MTU.
953              * XXX: IFF_FRAGMENTABLE (or such) flag has not been defined yet...
954              */
955         
956             || ifp->if_flags & IFF_FRAGMENTABLE
957 #endif
958             )
959         {
960                 /* Record statistics for this interface address. */
961                 if (ia && !(flags & IPV6_FORWARDING)) {
962                         ia->ia_ifa.if_opackets++;
963                         ia->ia_ifa.if_obytes += m->m_pkthdr.len;
964                 }
965 #ifdef IPSEC
966                 /* clean ipsec history once it goes out of the node */
967                 ipsec_delaux(m);
968 #endif
969                 error = nd6_output(ifp, origifp, m, dst, ro->ro_rt);
970                 goto done;
971         } else if (mtu < IPV6_MMTU) {
972                 /*
973                  * note that path MTU is never less than IPV6_MMTU
974                  * (see icmp6_input).
975                  */
976                 error = EMSGSIZE;
977                 in6_ifstat_inc(ifp, ifs6_out_fragfail);
978                 goto bad;
979         } else if (ip6->ip6_plen == 0) { /* jumbo payload cannot be fragmented */
980                 error = EMSGSIZE;
981                 in6_ifstat_inc(ifp, ifs6_out_fragfail);
982                 goto bad;
983         } else {
984                 struct mbuf **mnext, *m_frgpart;
985                 struct ip6_frag *ip6f;
986                 u_int32_t id = htonl(ip6_id++);
987                 u_char nextproto;
988
989                 /*
990                  * Too large for the destination or interface;
991                  * fragment if possible.
992                  * Must be able to put at least 8 bytes per fragment.
993                  */
994                 hlen = unfragpartlen;
995                 if (mtu > IPV6_MAXPACKET)
996                         mtu = IPV6_MAXPACKET;
997
998                 len = (mtu - hlen - sizeof(struct ip6_frag)) & ~7;
999                 if (len < 8) {
1000                         error = EMSGSIZE;
1001                         in6_ifstat_inc(ifp, ifs6_out_fragfail);
1002                         goto bad;
1003                 }
1004
1005                 mnext = &m->m_nextpkt;
1006
1007                 /*
1008                  * Change the next header field of the last header in the
1009                  * unfragmentable part.
1010                  */
1011                 if (exthdrs.ip6e_rthdr) {
1012                         nextproto = *mtod(exthdrs.ip6e_rthdr, u_char *);
1013                         *mtod(exthdrs.ip6e_rthdr, u_char *) = IPPROTO_FRAGMENT;
1014                 } else if (exthdrs.ip6e_dest1) {
1015                         nextproto = *mtod(exthdrs.ip6e_dest1, u_char *);
1016                         *mtod(exthdrs.ip6e_dest1, u_char *) = IPPROTO_FRAGMENT;
1017                 } else if (exthdrs.ip6e_hbh) {
1018                         nextproto = *mtod(exthdrs.ip6e_hbh, u_char *);
1019                         *mtod(exthdrs.ip6e_hbh, u_char *) = IPPROTO_FRAGMENT;
1020                 } else {
1021                         nextproto = ip6->ip6_nxt;
1022                         ip6->ip6_nxt = IPPROTO_FRAGMENT;
1023                 }
1024
1025                 /*
1026                  * Loop through length of segment after first fragment,
1027                  * make new header and copy data of each part and link onto
1028                  * chain.
1029                  */
1030                 m0 = m;
1031                 for (off = hlen; off < tlen; off += len) {
1032                         MGETHDR(m, M_DONTWAIT, MT_HEADER);
1033                         if (!m) {
1034                                 error = ENOBUFS;
1035                                 ip6stat.ip6s_odropped++;
1036                                 goto sendorfree;
1037                         }
1038                         m->m_pkthdr.rcvif = NULL;
1039                         m->m_flags = m0->m_flags & M_COPYFLAGS;
1040                         *mnext = m;
1041                         mnext = &m->m_nextpkt;
1042                         m->m_data += max_linkhdr;
1043                         mhip6 = mtod(m, struct ip6_hdr *);
1044                         *mhip6 = *ip6;
1045                         m->m_len = sizeof(*mhip6);
1046                         error = ip6_insertfraghdr(m0, m, hlen, &ip6f);
1047                         if (error) {
1048                                 ip6stat.ip6s_odropped++;
1049                                 goto sendorfree;
1050                         }
1051                         ip6f->ip6f_offlg = htons((u_short)((off - hlen) & ~7));
1052                         if (off + len >= tlen)
1053                                 len = tlen - off;
1054                         else
1055                                 ip6f->ip6f_offlg |= IP6F_MORE_FRAG;
1056                         mhip6->ip6_plen = htons((u_short)(len + hlen +
1057                                                           sizeof(*ip6f) -
1058                                                           sizeof(struct ip6_hdr)));
1059                         if ((m_frgpart = m_copy(m0, off, len)) == 0) {
1060                                 error = ENOBUFS;
1061                                 ip6stat.ip6s_odropped++;
1062                                 goto sendorfree;
1063                         }
1064                         m_cat(m, m_frgpart);
1065                         m->m_pkthdr.len = len + hlen + sizeof(*ip6f);
1066                         m->m_pkthdr.rcvif = (struct ifnet *)0;
1067                         ip6f->ip6f_reserved = 0;
1068                         ip6f->ip6f_ident = id;
1069                         ip6f->ip6f_nxt = nextproto;
1070                         ip6stat.ip6s_ofragments++;
1071                         in6_ifstat_inc(ifp, ifs6_out_fragcreat);
1072                 }
1073
1074                 in6_ifstat_inc(ifp, ifs6_out_fragok);
1075         }
1076
1077         /*
1078          * Remove leading garbages.
1079          */
1080 sendorfree:
1081         m = m0->m_nextpkt;
1082         m0->m_nextpkt = 0;
1083         m_freem(m0);
1084         for (m0 = m; m; m = m0) {
1085                 m0 = m->m_nextpkt;
1086                 m->m_nextpkt = 0;
1087                 if (error == 0) {
1088                         /* Record statistics for this interface address. */
1089                         if (ia) {
1090                                 ia->ia_ifa.if_opackets++;
1091                                 ia->ia_ifa.if_obytes += m->m_pkthdr.len;
1092                         }
1093 #ifdef IPSEC
1094                         /* clean ipsec history once it goes out of the node */
1095                         ipsec_delaux(m);
1096 #endif
1097                         error = nd6_output(ifp, origifp, m, dst, ro->ro_rt);
1098                 } else
1099                         m_freem(m);
1100         }
1101
1102         if (error == 0)
1103                 ip6stat.ip6s_fragmented++;
1104
1105 done:
1106         if (ro == &ip6route && ro->ro_rt) { /* brace necessary for RTFREE */
1107                 RTFREE(ro->ro_rt);
1108         } else if (ro_pmtu == &ip6route && ro_pmtu->ro_rt) {
1109                 RTFREE(ro_pmtu->ro_rt);
1110         }
1111
1112 #ifdef IPSEC
1113         if (sp != NULL)
1114                 key_freesp(sp);
1115 #endif /* IPSEC */
1116 #ifdef FAST_IPSEC
1117         if (sp != NULL)
1118                 KEY_FREESP(&sp);
1119 #endif /* FAST_IPSEC */
1120
1121         return(error);
1122
1123 freehdrs:
1124         m_freem(exthdrs.ip6e_hbh);      /* m_freem will check if mbuf is 0 */
1125         m_freem(exthdrs.ip6e_dest1);
1126         m_freem(exthdrs.ip6e_rthdr);
1127         m_freem(exthdrs.ip6e_dest2);
1128         /* fall through */
1129 bad:
1130         m_freem(m);
1131         goto done;
1132 }
1133
1134 static int
1135 ip6_copyexthdr(mp, hdr, hlen)
1136         struct mbuf **mp;
1137         caddr_t hdr;
1138         int hlen;
1139 {
1140         struct mbuf *m;
1141
1142         if (hlen > MCLBYTES)
1143                 return(ENOBUFS); /* XXX */
1144
1145         MGET(m, M_DONTWAIT, MT_DATA);
1146         if (!m)
1147                 return(ENOBUFS);
1148
1149         if (hlen > MLEN) {
1150                 MCLGET(m, M_DONTWAIT);
1151                 if ((m->m_flags & M_EXT) == 0) {
1152                         m_free(m);
1153                         return(ENOBUFS);
1154                 }
1155         }
1156         m->m_len = hlen;
1157         if (hdr)
1158                 bcopy(hdr, mtod(m, caddr_t), hlen);
1159
1160         *mp = m;
1161         return(0);
1162 }
1163
1164 /*
1165  * Insert jumbo payload option.
1166  */
1167 static int
1168 ip6_insert_jumboopt(exthdrs, plen)
1169         struct ip6_exthdrs *exthdrs;
1170         u_int32_t plen;
1171 {
1172         struct mbuf *mopt;
1173         u_char *optbuf;
1174         u_int32_t v;
1175
1176 #define JUMBOOPTLEN     8       /* length of jumbo payload option and padding */
1177
1178         /*
1179          * If there is no hop-by-hop options header, allocate new one.
1180          * If there is one but it doesn't have enough space to store the
1181          * jumbo payload option, allocate a cluster to store the whole options.
1182          * Otherwise, use it to store the options.
1183          */
1184         if (exthdrs->ip6e_hbh == 0) {
1185                 MGET(mopt, M_DONTWAIT, MT_DATA);
1186                 if (mopt == 0)
1187                         return(ENOBUFS);
1188                 mopt->m_len = JUMBOOPTLEN;
1189                 optbuf = mtod(mopt, u_char *);
1190                 optbuf[1] = 0;  /* = ((JUMBOOPTLEN) >> 3) - 1 */
1191                 exthdrs->ip6e_hbh = mopt;
1192         } else {
1193                 struct ip6_hbh *hbh;
1194
1195                 mopt = exthdrs->ip6e_hbh;
1196                 if (M_TRAILINGSPACE(mopt) < JUMBOOPTLEN) {
1197                         /*
1198                          * XXX assumption:
1199                          * - exthdrs->ip6e_hbh is not referenced from places
1200                          *   other than exthdrs.
1201                          * - exthdrs->ip6e_hbh is not an mbuf chain.
1202                          */
1203                         int oldoptlen = mopt->m_len;
1204                         struct mbuf *n;
1205
1206                         /*
1207                          * XXX: give up if the whole (new) hbh header does
1208                          * not fit even in an mbuf cluster.
1209                          */
1210                         if (oldoptlen + JUMBOOPTLEN > MCLBYTES)
1211                                 return(ENOBUFS);
1212
1213                         /*
1214                          * As a consequence, we must always prepare a cluster
1215                          * at this point.
1216                          */
1217                         MGET(n, M_DONTWAIT, MT_DATA);
1218                         if (n) {
1219                                 MCLGET(n, M_DONTWAIT);
1220                                 if ((n->m_flags & M_EXT) == 0) {
1221                                         m_freem(n);
1222                                         n = NULL;
1223                                 }
1224                         }
1225                         if (!n)
1226                                 return(ENOBUFS);
1227                         n->m_len = oldoptlen + JUMBOOPTLEN;
1228                         bcopy(mtod(mopt, caddr_t), mtod(n, caddr_t),
1229                               oldoptlen);
1230                         optbuf = mtod(n, caddr_t) + oldoptlen;
1231                         m_freem(mopt);
1232                         mopt = exthdrs->ip6e_hbh = n;
1233                 } else {
1234                         optbuf = mtod(mopt, u_char *) + mopt->m_len;
1235                         mopt->m_len += JUMBOOPTLEN;
1236                 }
1237                 optbuf[0] = IP6OPT_PADN;
1238                 optbuf[1] = 1;
1239
1240                 /*
1241                  * Adjust the header length according to the pad and
1242                  * the jumbo payload option.
1243                  */
1244                 hbh = mtod(mopt, struct ip6_hbh *);
1245                 hbh->ip6h_len += (JUMBOOPTLEN >> 3);
1246         }
1247
1248         /* fill in the option. */
1249         optbuf[2] = IP6OPT_JUMBO;
1250         optbuf[3] = 4;
1251         v = (u_int32_t)htonl(plen + JUMBOOPTLEN);
1252         bcopy(&v, &optbuf[4], sizeof(u_int32_t));
1253
1254         /* finally, adjust the packet header length */
1255         exthdrs->ip6e_ip6->m_pkthdr.len += JUMBOOPTLEN;
1256
1257         return(0);
1258 #undef JUMBOOPTLEN
1259 }
1260
1261 /*
1262  * Insert fragment header and copy unfragmentable header portions.
1263  */
1264 static int
1265 ip6_insertfraghdr(m0, m, hlen, frghdrp)
1266         struct mbuf *m0, *m;
1267         int hlen;
1268         struct ip6_frag **frghdrp;
1269 {
1270         struct mbuf *n, *mlast;
1271
1272         if (hlen > sizeof(struct ip6_hdr)) {
1273                 n = m_copym(m0, sizeof(struct ip6_hdr),
1274                             hlen - sizeof(struct ip6_hdr), M_DONTWAIT);
1275                 if (n == 0)
1276                         return(ENOBUFS);
1277                 m->m_next = n;
1278         } else
1279                 n = m;
1280
1281         /* Search for the last mbuf of unfragmentable part. */
1282         for (mlast = n; mlast->m_next; mlast = mlast->m_next)
1283                 ;
1284
1285         if ((mlast->m_flags & M_EXT) == 0 &&
1286             M_TRAILINGSPACE(mlast) >= sizeof(struct ip6_frag)) {
1287                 /* use the trailing space of the last mbuf for the fragment hdr */
1288                 *frghdrp =
1289                         (struct ip6_frag *)(mtod(mlast, caddr_t) + mlast->m_len);
1290                 mlast->m_len += sizeof(struct ip6_frag);
1291                 m->m_pkthdr.len += sizeof(struct ip6_frag);
1292         } else {
1293                 /* allocate a new mbuf for the fragment header */
1294                 struct mbuf *mfrg;
1295
1296                 MGET(mfrg, M_DONTWAIT, MT_DATA);
1297                 if (mfrg == 0)
1298                         return(ENOBUFS);
1299                 mfrg->m_len = sizeof(struct ip6_frag);
1300                 *frghdrp = mtod(mfrg, struct ip6_frag *);
1301                 mlast->m_next = mfrg;
1302         }
1303
1304         return(0);
1305 }
1306
1307 /*
1308  * IP6 socket option processing.
1309  */
1310 int
1311 ip6_ctloutput(struct socket *so, struct sockopt *sopt)
1312 {
1313         int privileged;
1314         struct inpcb *in6p = sotoinpcb(so);
1315         int error, optval;
1316         int level, op, optname;
1317         int optlen;
1318         struct thread *td;
1319
1320         if (sopt) {
1321                 level = sopt->sopt_level;
1322                 op = sopt->sopt_dir;
1323                 optname = sopt->sopt_name;
1324                 optlen = sopt->sopt_valsize;
1325                 td = sopt->sopt_td;
1326         } else {
1327                 panic("ip6_ctloutput: arg soopt is NULL");
1328                 /* NOT REACHED */
1329                 td = NULL;
1330         }
1331         error = optval = 0;
1332
1333         privileged = (td == NULL || suser(td)) ? 0 : 1;
1334
1335         if (level == IPPROTO_IPV6) {
1336                 switch (op) {
1337
1338                 case SOPT_SET:
1339                         switch (optname) {
1340                         case IPV6_PKTOPTIONS:
1341                         {
1342                                 struct mbuf *m;
1343
1344                                 error = soopt_getm(sopt, &m); /* XXX */
1345                                 if (error != NULL)
1346                                         break;
1347                                 error = soopt_mcopyin(sopt, m); /* XXX */
1348                                 if (error != NULL)
1349                                         break;
1350                                 error = ip6_pcbopts(&in6p->in6p_outputopts,
1351                                                     m, so, sopt);
1352                                 m_freem(m); /* XXX */
1353                                 break;
1354                         }
1355
1356                         /*
1357                          * Use of some Hop-by-Hop options or some
1358                          * Destination options, might require special
1359                          * privilege.  That is, normal applications
1360                          * (without special privilege) might be forbidden
1361                          * from setting certain options in outgoing packets,
1362                          * and might never see certain options in received
1363                          * packets. [RFC 2292 Section 6]
1364                          * KAME specific note:
1365                          *  KAME prevents non-privileged users from sending or
1366                          *  receiving ANY hbh/dst options in order to avoid
1367                          *  overhead of parsing options in the kernel.
1368                          */
1369                         case IPV6_UNICAST_HOPS:
1370                         case IPV6_CHECKSUM:
1371                         case IPV6_FAITH:
1372
1373                         case IPV6_V6ONLY:
1374                                 if (optlen != sizeof(int)) {
1375                                         error = EINVAL;
1376                                         break;
1377                                 }
1378                                 error = sooptcopyin(sopt, &optval,
1379                                         sizeof optval, sizeof optval);
1380                                 if (error)
1381                                         break;
1382                                 switch (optname) {
1383
1384                                 case IPV6_UNICAST_HOPS:
1385                                         if (optval < -1 || optval >= 256)
1386                                                 error = EINVAL;
1387                                         else {
1388                                                 /* -1 = kernel default */
1389                                                 in6p->in6p_hops = optval;
1390
1391                                                 if ((in6p->in6p_vflag &
1392                                                      INP_IPV4) != 0)
1393                                                         in6p->inp_ip_ttl = optval;
1394                                         }
1395                                         break;
1396 #define OPTSET(bit) \
1397 do { \
1398         if (optval) \
1399                 in6p->in6p_flags |= (bit); \
1400         else \
1401                 in6p->in6p_flags &= ~(bit); \
1402 } while (0)
1403 #define OPTBIT(bit) (in6p->in6p_flags & (bit) ? 1 : 0)
1404
1405                                 case IPV6_CHECKSUM:
1406                                         in6p->in6p_cksum = optval;
1407                                         break;
1408
1409                                 case IPV6_FAITH:
1410                                         OPTSET(IN6P_FAITH);
1411                                         break;
1412
1413                                 case IPV6_V6ONLY:
1414                                         /*
1415                                          * make setsockopt(IPV6_V6ONLY)
1416                                          * available only prior to bind(2).
1417                                          * see ipng mailing list, Jun 22 2001.
1418                                          */
1419                                         if (in6p->in6p_lport ||
1420                                             !IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr))
1421                                         {
1422                                                 error = EINVAL;
1423                                                 break;
1424                                         }
1425                                         OPTSET(IN6P_IPV6_V6ONLY);
1426                                         if (optval)
1427                                                 in6p->in6p_vflag &= ~INP_IPV4;
1428                                         else
1429                                                 in6p->in6p_vflag |= INP_IPV4;
1430                                         break;
1431                                 }
1432                                 break;
1433
1434                         case IPV6_PKTINFO:
1435                         case IPV6_HOPLIMIT:
1436                         case IPV6_HOPOPTS:
1437                         case IPV6_DSTOPTS:
1438                         case IPV6_RTHDR:
1439                                 /* RFC 2292 */
1440                                 if (optlen != sizeof(int)) {
1441                                         error = EINVAL;
1442                                         break;
1443                                 }
1444                                 error = sooptcopyin(sopt, &optval,
1445                                         sizeof optval, sizeof optval);
1446                                 if (error)
1447                                         break;
1448                                 switch (optname) {
1449                                 case IPV6_PKTINFO:
1450                                         OPTSET(IN6P_PKTINFO);
1451                                         break;
1452                                 case IPV6_HOPLIMIT:
1453                                         OPTSET(IN6P_HOPLIMIT);
1454                                         break;
1455                                 case IPV6_HOPOPTS:
1456                                         /*
1457                                          * Check super-user privilege.
1458                                          * See comments for IPV6_RECVHOPOPTS.
1459                                          */
1460                                         if (!privileged)
1461                                                 return(EPERM);
1462                                         OPTSET(IN6P_HOPOPTS);
1463                                         break;
1464                                 case IPV6_DSTOPTS:
1465                                         if (!privileged)
1466                                                 return(EPERM);
1467                                         OPTSET(IN6P_DSTOPTS|IN6P_RTHDRDSTOPTS); /* XXX */
1468                                         break;
1469                                 case IPV6_RTHDR:
1470                                         OPTSET(IN6P_RTHDR);
1471                                         break;
1472                                 }
1473                                 break;
1474 #undef OPTSET
1475
1476                         case IPV6_MULTICAST_IF:
1477                         case IPV6_MULTICAST_HOPS:
1478                         case IPV6_MULTICAST_LOOP:
1479                         case IPV6_JOIN_GROUP:
1480                         case IPV6_LEAVE_GROUP:
1481                             {
1482                                 struct mbuf *m;
1483                                 if (sopt->sopt_valsize > MLEN) {
1484                                         error = EMSGSIZE;
1485                                         break;
1486                                 }
1487                                 /* XXX */
1488                                 MGET(m, sopt->sopt_td ? M_WAIT : M_DONTWAIT, MT_HEADER);
1489                                 if (m == 0) {
1490                                         error = ENOBUFS;
1491                                         break;
1492                                 }
1493                                 m->m_len = sopt->sopt_valsize;
1494                                 error = sooptcopyin(sopt, mtod(m, char *),
1495                                                     m->m_len, m->m_len);
1496                                 error = ip6_setmoptions(sopt->sopt_name,
1497                                                         &in6p->in6p_moptions,
1498                                                         m);
1499                                 (void)m_free(m);
1500                             }
1501                                 break;
1502
1503                         case IPV6_PORTRANGE:
1504                                 error = sooptcopyin(sopt, &optval,
1505                                     sizeof optval, sizeof optval);
1506                                 if (error)
1507                                         break;
1508
1509                                 switch (optval) {
1510                                 case IPV6_PORTRANGE_DEFAULT:
1511                                         in6p->in6p_flags &= ~(IN6P_LOWPORT);
1512                                         in6p->in6p_flags &= ~(IN6P_HIGHPORT);
1513                                         break;
1514
1515                                 case IPV6_PORTRANGE_HIGH:
1516                                         in6p->in6p_flags &= ~(IN6P_LOWPORT);
1517                                         in6p->in6p_flags |= IN6P_HIGHPORT;
1518                                         break;
1519
1520                                 case IPV6_PORTRANGE_LOW:
1521                                         in6p->in6p_flags &= ~(IN6P_HIGHPORT);
1522                                         in6p->in6p_flags |= IN6P_LOWPORT;
1523                                         break;
1524
1525                                 default:
1526                                         error = EINVAL;
1527                                         break;
1528                                 }
1529                                 break;
1530
1531 #if defined(IPSEC) || defined(FAST_IPSEC)
1532                         case IPV6_IPSEC_POLICY:
1533                             {
1534                                 caddr_t req = NULL;
1535                                 size_t len = 0;
1536                                 struct mbuf *m;
1537
1538                                 if ((error = soopt_getm(sopt, &m)) != 0) /* XXX */
1539                                         break;
1540                                 if ((error = soopt_mcopyin(sopt, m)) != 0) /* XXX */
1541                                         break;
1542                                 if (m) {
1543                                         req = mtod(m, caddr_t);
1544                                         len = m->m_len;
1545                                 }
1546                                 error = ipsec6_set_policy(in6p, optname, req,
1547                                                           len, privileged);
1548                                 m_freem(m);
1549                             }
1550                                 break;
1551 #endif /* KAME IPSEC */
1552
1553                         case IPV6_FW_ADD:
1554                         case IPV6_FW_DEL:
1555                         case IPV6_FW_FLUSH:
1556                         case IPV6_FW_ZERO:
1557                             {
1558                                 struct mbuf *m;
1559                                 struct mbuf **mp = &m;
1560
1561                                 if (ip6_fw_ctl_ptr == NULL)
1562                                         return EINVAL;
1563                                 /* XXX */
1564                                 if ((error = soopt_getm(sopt, &m)) != 0)
1565                                         break;
1566                                 /* XXX */
1567                                 if ((error = soopt_mcopyin(sopt, m)) != 0)
1568                                         break;
1569                                 error = (*ip6_fw_ctl_ptr)(optname, mp);
1570                                 m = *mp;
1571                             }
1572                                 break;
1573
1574                         default:
1575                                 error = ENOPROTOOPT;
1576                                 break;
1577                         }
1578                         break;
1579
1580                 case SOPT_GET:
1581                         switch (optname) {
1582
1583                         case IPV6_PKTOPTIONS:
1584                                 if (in6p->in6p_options) {
1585                                         struct mbuf *m;
1586                                         m = m_copym(in6p->in6p_options,
1587                                             0, M_COPYALL, M_WAIT);
1588                                         error = soopt_mcopyout(sopt, m);
1589                                         if (error == 0)
1590                                                 m_freem(m);
1591                                 } else
1592                                         sopt->sopt_valsize = 0;
1593                                 break;
1594
1595                         case IPV6_UNICAST_HOPS:
1596                         case IPV6_CHECKSUM:
1597
1598                         case IPV6_FAITH:
1599                         case IPV6_V6ONLY:
1600                         case IPV6_PORTRANGE:
1601                                 switch (optname) {
1602
1603                                 case IPV6_UNICAST_HOPS:
1604                                         optval = in6p->in6p_hops;
1605                                         break;
1606
1607                                 case IPV6_CHECKSUM:
1608                                         optval = in6p->in6p_cksum;
1609                                         break;
1610
1611                                 case IPV6_FAITH:
1612                                         optval = OPTBIT(IN6P_FAITH);
1613                                         break;
1614
1615                                 case IPV6_V6ONLY:
1616                                         optval = OPTBIT(IN6P_IPV6_V6ONLY);
1617                                         break;
1618
1619                                 case IPV6_PORTRANGE:
1620                                     {
1621                                         int flags;
1622                                         flags = in6p->in6p_flags;
1623                                         if (flags & IN6P_HIGHPORT)
1624                                                 optval = IPV6_PORTRANGE_HIGH;
1625                                         else if (flags & IN6P_LOWPORT)
1626                                                 optval = IPV6_PORTRANGE_LOW;
1627                                         else
1628                                                 optval = 0;
1629                                         break;
1630                                     }
1631                                 }
1632                                 error = sooptcopyout(sopt, &optval,
1633                                         sizeof optval);
1634                                 break;
1635
1636                         case IPV6_PKTINFO:
1637                         case IPV6_HOPLIMIT:
1638                         case IPV6_HOPOPTS:
1639                         case IPV6_RTHDR:
1640                         case IPV6_DSTOPTS:
1641                                 if (optname == IPV6_HOPOPTS ||
1642                                     optname == IPV6_DSTOPTS ||
1643                                     !privileged)
1644                                         return(EPERM);
1645                                 switch (optname) {
1646                                 case IPV6_PKTINFO:
1647                                         optval = OPTBIT(IN6P_PKTINFO);
1648                                         break;
1649                                 case IPV6_HOPLIMIT:
1650                                         optval = OPTBIT(IN6P_HOPLIMIT);
1651                                         break;
1652                                 case IPV6_HOPOPTS:
1653                                         if (!privileged)
1654                                                 return(EPERM);
1655                                         optval = OPTBIT(IN6P_HOPOPTS);
1656                                         break;
1657                                 case IPV6_RTHDR:
1658                                         optval = OPTBIT(IN6P_RTHDR);
1659                                         break;
1660                                 case IPV6_DSTOPTS:
1661                                         if (!privileged)
1662                                                 return(EPERM);
1663                                         optval = OPTBIT(IN6P_DSTOPTS|IN6P_RTHDRDSTOPTS);
1664                                         break;
1665                                 }
1666                                 error = sooptcopyout(sopt, &optval,
1667                                         sizeof optval);
1668                                 break;
1669
1670                         case IPV6_MULTICAST_IF:
1671                         case IPV6_MULTICAST_HOPS:
1672                         case IPV6_MULTICAST_LOOP:
1673                         case IPV6_JOIN_GROUP:
1674                         case IPV6_LEAVE_GROUP:
1675                             {
1676                                 struct mbuf *m;
1677                                 error = ip6_getmoptions(sopt->sopt_name,
1678                                                 in6p->in6p_moptions, &m);
1679                                 if (error == 0)
1680                                         error = sooptcopyout(sopt,
1681                                                 mtod(m, char *), m->m_len);
1682                                 m_freem(m);
1683                             }
1684                                 break;
1685
1686 #if defined(IPSEC) || defined(FAST_IPSEC)
1687                         case IPV6_IPSEC_POLICY:
1688                           {
1689                                 caddr_t req = NULL;
1690                                 size_t len = 0;
1691                                 struct mbuf *m = NULL;
1692                                 struct mbuf **mp = &m;
1693
1694                                 error = soopt_getm(sopt, &m); /* XXX */
1695                                 if (error != NULL)
1696                                         break;
1697                                 error = soopt_mcopyin(sopt, m); /* XXX */
1698                                 if (error != NULL)
1699                                         break;
1700                                 if (m) {
1701                                         req = mtod(m, caddr_t);
1702                                         len = m->m_len;
1703                                 }
1704                                 error = ipsec6_get_policy(in6p, req, len, mp);
1705                                 if (error == 0)
1706                                         error = soopt_mcopyout(sopt, m); /*XXX*/
1707                                 if (error == 0 && m)
1708                                         m_freem(m);
1709                                 break;
1710                           }
1711 #endif /* KAME IPSEC */
1712
1713                         case IPV6_FW_GET:
1714                           {
1715                                 struct mbuf *m;
1716                                 struct mbuf **mp = &m;
1717
1718                                 if (ip6_fw_ctl_ptr == NULL)
1719                                 {
1720                                         return EINVAL;
1721                                 }
1722                                 error = (*ip6_fw_ctl_ptr)(optname, mp);
1723                                 if (error == 0)
1724                                         error = soopt_mcopyout(sopt, m); /* XXX */
1725                                 if (error == 0 && m)
1726                                         m_freem(m);
1727                           }
1728                                 break;
1729
1730                         default:
1731                                 error = ENOPROTOOPT;
1732                                 break;
1733                         }
1734                         break;
1735                 }
1736         } else {
1737                 error = EINVAL;
1738         }
1739         return(error);
1740 }
1741
1742 /*
1743  * Set up IP6 options in pcb for insertion in output packets or
1744  * specifying behavior of outgoing packets.
1745  */
1746 static int
1747 ip6_pcbopts(pktopt, m, so, sopt)
1748         struct ip6_pktopts **pktopt;
1749         struct mbuf *m;
1750         struct socket *so;
1751         struct sockopt *sopt;
1752 {
1753         struct ip6_pktopts *opt = *pktopt;
1754         int error = 0;
1755         struct thread *td = sopt->sopt_td;
1756         int priv = 0;
1757
1758         /* turn off any old options. */
1759         if (opt) {
1760 #ifdef DIAGNOSTIC
1761                 if (opt->ip6po_pktinfo || opt->ip6po_nexthop ||
1762                     opt->ip6po_hbh || opt->ip6po_dest1 || opt->ip6po_dest2 ||
1763                     opt->ip6po_rhinfo.ip6po_rhi_rthdr)
1764                         printf("ip6_pcbopts: all specified options are cleared.\n");
1765 #endif
1766                 ip6_clearpktopts(opt, 1, -1);
1767         } else
1768                 opt = malloc(sizeof(*opt), M_IP6OPT, M_WAITOK);
1769         *pktopt = NULL;
1770
1771         if (!m || m->m_len == 0) {
1772                 /*
1773                  * Only turning off any previous options, regardless of
1774                  * whether the opt is just created or given.
1775                  */
1776                 free(opt, M_IP6OPT);
1777                 return(0);
1778         }
1779
1780         /*  set options specified by user. */
1781         if (suser(td) == 0)
1782                 priv = 1;
1783         if ((error = ip6_setpktoptions(m, opt, priv, 1)) != 0) {
1784                 ip6_clearpktopts(opt, 1, -1); /* XXX: discard all options */
1785                 free(opt, M_IP6OPT);
1786                 return(error);
1787         }
1788         *pktopt = opt;
1789         return(0);
1790 }
1791
1792 /*
1793  * initialize ip6_pktopts.  beware that there are non-zero default values in
1794  * the struct.
1795  */
1796 void
1797 init_ip6pktopts(opt)
1798         struct ip6_pktopts *opt;
1799 {
1800
1801         bzero(opt, sizeof(*opt));
1802         opt->ip6po_hlim = -1;   /* -1 means default hop limit */
1803 }
1804
1805 void
1806 ip6_clearpktopts(pktopt, needfree, optname)
1807         struct ip6_pktopts *pktopt;
1808         int needfree, optname;
1809 {
1810         if (pktopt == NULL)
1811                 return;
1812
1813         if (optname == -1) {
1814                 if (needfree && pktopt->ip6po_pktinfo)
1815                         free(pktopt->ip6po_pktinfo, M_IP6OPT);
1816                 pktopt->ip6po_pktinfo = NULL;
1817         }
1818         if (optname == -1)
1819                 pktopt->ip6po_hlim = -1;
1820         if (optname == -1) {
1821                 if (needfree && pktopt->ip6po_nexthop)
1822                         free(pktopt->ip6po_nexthop, M_IP6OPT);
1823                 pktopt->ip6po_nexthop = NULL;
1824         }
1825         if (optname == -1) {
1826                 if (needfree && pktopt->ip6po_hbh)
1827                         free(pktopt->ip6po_hbh, M_IP6OPT);
1828                 pktopt->ip6po_hbh = NULL;
1829         }
1830         if (optname == -1) {
1831                 if (needfree && pktopt->ip6po_dest1)
1832                         free(pktopt->ip6po_dest1, M_IP6OPT);
1833                 pktopt->ip6po_dest1 = NULL;
1834         }
1835         if (optname == -1) {
1836                 if (needfree && pktopt->ip6po_rhinfo.ip6po_rhi_rthdr)
1837                         free(pktopt->ip6po_rhinfo.ip6po_rhi_rthdr, M_IP6OPT);
1838                 pktopt->ip6po_rhinfo.ip6po_rhi_rthdr = NULL;
1839                 if (pktopt->ip6po_route.ro_rt) {
1840                         RTFREE(pktopt->ip6po_route.ro_rt);
1841                         pktopt->ip6po_route.ro_rt = NULL;
1842                 }
1843         }
1844         if (optname == -1) {
1845                 if (needfree && pktopt->ip6po_dest2)
1846                         free(pktopt->ip6po_dest2, M_IP6OPT);
1847                 pktopt->ip6po_dest2 = NULL;
1848         }
1849 }
1850
1851 #define PKTOPT_EXTHDRCPY(type) \
1852 do {\
1853         if (src->type) {\
1854                 int hlen =\
1855                         (((struct ip6_ext *)src->type)->ip6e_len + 1) << 3;\
1856                 dst->type = malloc(hlen, M_IP6OPT, canwait);\
1857                 if (dst->type == NULL && canwait == M_NOWAIT)\
1858                         goto bad;\
1859                 bcopy(src->type, dst->type, hlen);\
1860         }\
1861 } while (0)
1862
1863 struct ip6_pktopts *
1864 ip6_copypktopts(src, canwait)
1865         struct ip6_pktopts *src;
1866         int canwait;
1867 {
1868         struct ip6_pktopts *dst;
1869
1870         if (src == NULL) {
1871                 printf("ip6_clearpktopts: invalid argument\n");
1872                 return(NULL);
1873         }
1874
1875         dst = malloc(sizeof(*dst), M_IP6OPT, canwait);
1876         if (dst == NULL && canwait == M_NOWAIT)
1877                 return (NULL);
1878         bzero(dst, sizeof(*dst));
1879
1880         dst->ip6po_hlim = src->ip6po_hlim;
1881         if (src->ip6po_pktinfo) {
1882                 dst->ip6po_pktinfo = malloc(sizeof(*dst->ip6po_pktinfo),
1883                                             M_IP6OPT, canwait);
1884                 if (dst->ip6po_pktinfo == NULL && canwait == M_NOWAIT)
1885                         goto bad;
1886                 *dst->ip6po_pktinfo = *src->ip6po_pktinfo;
1887         }
1888         if (src->ip6po_nexthop) {
1889                 dst->ip6po_nexthop = malloc(src->ip6po_nexthop->sa_len,
1890                                             M_IP6OPT, canwait);
1891                 if (dst->ip6po_nexthop == NULL && canwait == M_NOWAIT)
1892                         goto bad;
1893                 bcopy(src->ip6po_nexthop, dst->ip6po_nexthop,
1894                       src->ip6po_nexthop->sa_len);
1895         }
1896         PKTOPT_EXTHDRCPY(ip6po_hbh);
1897         PKTOPT_EXTHDRCPY(ip6po_dest1);
1898         PKTOPT_EXTHDRCPY(ip6po_dest2);
1899         PKTOPT_EXTHDRCPY(ip6po_rthdr); /* not copy the cached route */
1900         return(dst);
1901
1902   bad:
1903         if (dst->ip6po_pktinfo) free(dst->ip6po_pktinfo, M_IP6OPT);
1904         if (dst->ip6po_nexthop) free(dst->ip6po_nexthop, M_IP6OPT);
1905         if (dst->ip6po_hbh) free(dst->ip6po_hbh, M_IP6OPT);
1906         if (dst->ip6po_dest1) free(dst->ip6po_dest1, M_IP6OPT);
1907         if (dst->ip6po_dest2) free(dst->ip6po_dest2, M_IP6OPT);
1908         if (dst->ip6po_rthdr) free(dst->ip6po_rthdr, M_IP6OPT);
1909         free(dst, M_IP6OPT);
1910         return(NULL);
1911 }
1912 #undef PKTOPT_EXTHDRCPY
1913
1914 void
1915 ip6_freepcbopts(pktopt)
1916         struct ip6_pktopts *pktopt;
1917 {
1918         if (pktopt == NULL)
1919                 return;
1920
1921         ip6_clearpktopts(pktopt, 1, -1);
1922
1923         free(pktopt, M_IP6OPT);
1924 }
1925
1926 /*
1927  * Set the IP6 multicast options in response to user setsockopt().
1928  */
1929 static int
1930 ip6_setmoptions(optname, im6op, m)
1931         int optname;
1932         struct ip6_moptions **im6op;
1933         struct mbuf *m;
1934 {
1935         int error = 0;
1936         u_int loop, ifindex;
1937         struct ipv6_mreq *mreq;
1938         struct ifnet *ifp;
1939         struct ip6_moptions *im6o = *im6op;
1940         struct route_in6 ro;
1941         struct sockaddr_in6 *dst;
1942         struct in6_multi_mship *imm;
1943         struct thread *td = curthread;  /* XXX */
1944
1945         if (im6o == NULL) {
1946                 /*
1947                  * No multicast option buffer attached to the pcb;
1948                  * allocate one and initialize to default values.
1949                  */
1950                 im6o = (struct ip6_moptions *)
1951                         malloc(sizeof(*im6o), M_IPMOPTS, M_WAITOK);
1952
1953                 if (im6o == NULL)
1954                         return(ENOBUFS);
1955                 *im6op = im6o;
1956                 im6o->im6o_multicast_ifp = NULL;
1957                 im6o->im6o_multicast_hlim = ip6_defmcasthlim;
1958                 im6o->im6o_multicast_loop = IPV6_DEFAULT_MULTICAST_LOOP;
1959                 LIST_INIT(&im6o->im6o_memberships);
1960         }
1961
1962         switch (optname) {
1963
1964         case IPV6_MULTICAST_IF:
1965                 /*
1966                  * Select the interface for outgoing multicast packets.
1967                  */
1968                 if (m == NULL || m->m_len != sizeof(u_int)) {
1969                         error = EINVAL;
1970                         break;
1971                 }
1972                 bcopy(mtod(m, u_int *), &ifindex, sizeof(ifindex));
1973                 if (ifindex < 0 || if_index < ifindex) {
1974                         error = ENXIO;  /* XXX EINVAL? */
1975                         break;
1976                 }
1977                 ifp = ifindex2ifnet[ifindex];
1978                 if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0) {
1979                         error = EADDRNOTAVAIL;
1980                         break;
1981                 }
1982                 im6o->im6o_multicast_ifp = ifp;
1983                 break;
1984
1985         case IPV6_MULTICAST_HOPS:
1986             {
1987                 /*
1988                  * Set the IP6 hoplimit for outgoing multicast packets.
1989                  */
1990                 int optval;
1991                 if (m == NULL || m->m_len != sizeof(int)) {
1992                         error = EINVAL;
1993                         break;
1994                 }
1995                 bcopy(mtod(m, u_int *), &optval, sizeof(optval));
1996                 if (optval < -1 || optval >= 256)
1997                         error = EINVAL;
1998                 else if (optval == -1)
1999                         im6o->im6o_multicast_hlim = ip6_defmcasthlim;
2000                 else
2001                         im6o->im6o_multicast_hlim = optval;
2002                 break;
2003             }
2004
2005         case IPV6_MULTICAST_LOOP:
2006                 /*
2007                  * Set the loopback flag for outgoing multicast packets.
2008                  * Must be zero or one.
2009                  */
2010                 if (m == NULL || m->m_len != sizeof(u_int)) {
2011                         error = EINVAL;
2012                         break;
2013                 }
2014                 bcopy(mtod(m, u_int *), &loop, sizeof(loop));
2015                 if (loop > 1) {
2016                         error = EINVAL;
2017                         break;
2018                 }
2019                 im6o->im6o_multicast_loop = loop;
2020                 break;
2021
2022         case IPV6_JOIN_GROUP:
2023                 /*
2024                  * Add a multicast group membership.
2025                  * Group must be a valid IP6 multicast address.
2026                  */
2027                 if (m == NULL || m->m_len != sizeof(struct ipv6_mreq)) {
2028                         error = EINVAL;
2029                         break;
2030                 }
2031                 mreq = mtod(m, struct ipv6_mreq *);
2032                 if (IN6_IS_ADDR_UNSPECIFIED(&mreq->ipv6mr_multiaddr)) {
2033                         /*
2034                          * We use the unspecified address to specify to accept
2035                          * all multicast addresses. Only super user is allowed
2036                          * to do this.
2037                          */
2038                         if (suser(td))
2039                         {
2040                                 error = EACCES;
2041                                 break;
2042                         }
2043                 } else if (!IN6_IS_ADDR_MULTICAST(&mreq->ipv6mr_multiaddr)) {
2044                         error = EINVAL;
2045                         break;
2046                 }
2047
2048                 /*
2049                  * If the interface is specified, validate it.
2050                  */
2051                 if (mreq->ipv6mr_interface < 0
2052                  || if_index < mreq->ipv6mr_interface) {
2053                         error = ENXIO;  /* XXX EINVAL? */
2054                         break;
2055                 }
2056                 /*
2057                  * If no interface was explicitly specified, choose an
2058                  * appropriate one according to the given multicast address.
2059                  */
2060                 if (mreq->ipv6mr_interface == 0) {
2061                         /*
2062                          * If the multicast address is in node-local scope,
2063                          * the interface should be a loopback interface.
2064                          * Otherwise, look up the routing table for the
2065                          * address, and choose the outgoing interface.
2066                          *   XXX: is it a good approach?
2067                          */
2068                         if (IN6_IS_ADDR_MC_NODELOCAL(&mreq->ipv6mr_multiaddr)) {
2069                                 ifp = &loif[0];
2070                         } else {
2071                                 ro.ro_rt = NULL;
2072                                 dst = (struct sockaddr_in6 *)&ro.ro_dst;
2073                                 bzero(dst, sizeof(*dst));
2074                                 dst->sin6_len = sizeof(struct sockaddr_in6);
2075                                 dst->sin6_family = AF_INET6;
2076                                 dst->sin6_addr = mreq->ipv6mr_multiaddr;
2077                                 rtalloc((struct route *)&ro);
2078                                 if (ro.ro_rt == NULL) {
2079                                         error = EADDRNOTAVAIL;
2080                                         break;
2081                                 }
2082                                 ifp = ro.ro_rt->rt_ifp;
2083                                 rtfree(ro.ro_rt);
2084                         }
2085                 } else
2086                         ifp = ifindex2ifnet[mreq->ipv6mr_interface];
2087
2088                 /*
2089                  * See if we found an interface, and confirm that it
2090                  * supports multicast
2091                  */
2092                 if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0) {
2093                         error = EADDRNOTAVAIL;
2094                         break;
2095                 }
2096                 /*
2097                  * Put interface index into the multicast address,
2098                  * if the address has link-local scope.
2099                  */
2100                 if (IN6_IS_ADDR_MC_LINKLOCAL(&mreq->ipv6mr_multiaddr)) {
2101                         mreq->ipv6mr_multiaddr.s6_addr16[1]
2102                                 = htons(mreq->ipv6mr_interface);
2103                 }
2104                 /*
2105                  * See if the membership already exists.
2106                  */
2107                 for (imm = im6o->im6o_memberships.lh_first;
2108                      imm != NULL; imm = imm->i6mm_chain.le_next)
2109                         if (imm->i6mm_maddr->in6m_ifp == ifp &&
2110                             IN6_ARE_ADDR_EQUAL(&imm->i6mm_maddr->in6m_addr,
2111                                                &mreq->ipv6mr_multiaddr))
2112                                 break;
2113                 if (imm != NULL) {
2114                         error = EADDRINUSE;
2115                         break;
2116                 }
2117                 /*
2118                  * Everything looks good; add a new record to the multicast
2119                  * address list for the given interface.
2120                  */
2121                 imm = malloc(sizeof(*imm), M_IPMADDR, M_WAITOK);
2122                 if (imm == NULL) {
2123                         error = ENOBUFS;
2124                         break;
2125                 }
2126                 if ((imm->i6mm_maddr =
2127                      in6_addmulti(&mreq->ipv6mr_multiaddr, ifp, &error)) == NULL) {
2128                         free(imm, M_IPMADDR);
2129                         break;
2130                 }
2131                 LIST_INSERT_HEAD(&im6o->im6o_memberships, imm, i6mm_chain);
2132                 break;
2133
2134         case IPV6_LEAVE_GROUP:
2135                 /*
2136                  * Drop a multicast group membership.
2137                  * Group must be a valid IP6 multicast address.
2138                  */
2139                 if (m == NULL || m->m_len != sizeof(struct ipv6_mreq)) {
2140                         error = EINVAL;
2141                         break;
2142                 }
2143                 mreq = mtod(m, struct ipv6_mreq *);
2144                 if (IN6_IS_ADDR_UNSPECIFIED(&mreq->ipv6mr_multiaddr)) {
2145                         if (suser(td)) {
2146                                 error = EACCES;
2147                                 break;
2148                         }
2149                 } else if (!IN6_IS_ADDR_MULTICAST(&mreq->ipv6mr_multiaddr)) {
2150                         error = EINVAL;
2151                         break;
2152                 }
2153                 /*
2154                  * If an interface address was specified, get a pointer
2155                  * to its ifnet structure.
2156                  */
2157                 if (mreq->ipv6mr_interface < 0
2158                  || if_index < mreq->ipv6mr_interface) {
2159                         error = ENXIO;  /* XXX EINVAL? */
2160                         break;
2161                 }
2162                 ifp = ifindex2ifnet[mreq->ipv6mr_interface];
2163                 /*
2164                  * Put interface index into the multicast address,
2165                  * if the address has link-local scope.
2166                  */
2167                 if (IN6_IS_ADDR_MC_LINKLOCAL(&mreq->ipv6mr_multiaddr)) {
2168                         mreq->ipv6mr_multiaddr.s6_addr16[1]
2169                                 = htons(mreq->ipv6mr_interface);
2170                 }
2171                 /*
2172                  * Find the membership in the membership list.
2173                  */
2174                 for (imm = im6o->im6o_memberships.lh_first;
2175                      imm != NULL; imm = imm->i6mm_chain.le_next) {
2176                         if ((ifp == NULL ||
2177                              imm->i6mm_maddr->in6m_ifp == ifp) &&
2178                             IN6_ARE_ADDR_EQUAL(&imm->i6mm_maddr->in6m_addr,
2179                                                &mreq->ipv6mr_multiaddr))
2180                                 break;
2181                 }
2182                 if (imm == NULL) {
2183                         /* Unable to resolve interface */
2184                         error = EADDRNOTAVAIL;
2185                         break;
2186                 }
2187                 /*
2188                  * Give up the multicast address record to which the
2189                  * membership points.
2190                  */
2191                 LIST_REMOVE(imm, i6mm_chain);
2192                 in6_delmulti(imm->i6mm_maddr);
2193                 free(imm, M_IPMADDR);
2194                 break;
2195
2196         default:
2197                 error = EOPNOTSUPP;
2198                 break;
2199         }
2200
2201         /*
2202          * If all options have default values, no need to keep the mbuf.
2203          */
2204         if (im6o->im6o_multicast_ifp == NULL &&
2205             im6o->im6o_multicast_hlim == ip6_defmcasthlim &&
2206             im6o->im6o_multicast_loop == IPV6_DEFAULT_MULTICAST_LOOP &&
2207             im6o->im6o_memberships.lh_first == NULL) {
2208                 free(*im6op, M_IPMOPTS);
2209                 *im6op = NULL;
2210         }
2211
2212         return(error);
2213 }
2214
2215 /*
2216  * Return the IP6 multicast options in response to user getsockopt().
2217  */
2218 static int
2219 ip6_getmoptions(optname, im6o, mp)
2220         int optname;
2221         struct ip6_moptions *im6o;
2222         struct mbuf **mp;
2223 {
2224         u_int *hlim, *loop, *ifindex;
2225
2226         *mp = m_get(M_WAIT, MT_HEADER);         /* XXX */
2227
2228         switch (optname) {
2229
2230         case IPV6_MULTICAST_IF:
2231                 ifindex = mtod(*mp, u_int *);
2232                 (*mp)->m_len = sizeof(u_int);
2233                 if (im6o == NULL || im6o->im6o_multicast_ifp == NULL)
2234                         *ifindex = 0;
2235                 else
2236                         *ifindex = im6o->im6o_multicast_ifp->if_index;
2237                 return(0);
2238
2239         case IPV6_MULTICAST_HOPS:
2240                 hlim = mtod(*mp, u_int *);
2241                 (*mp)->m_len = sizeof(u_int);
2242                 if (im6o == NULL)
2243                         *hlim = ip6_defmcasthlim;
2244                 else
2245                         *hlim = im6o->im6o_multicast_hlim;
2246                 return(0);
2247
2248         case IPV6_MULTICAST_LOOP:
2249                 loop = mtod(*mp, u_int *);
2250                 (*mp)->m_len = sizeof(u_int);
2251                 if (im6o == NULL)
2252                         *loop = ip6_defmcasthlim;
2253                 else
2254                         *loop = im6o->im6o_multicast_loop;
2255                 return(0);
2256
2257         default:
2258                 return(EOPNOTSUPP);
2259         }
2260 }
2261
2262 /*
2263  * Discard the IP6 multicast options.
2264  */
2265 void
2266 ip6_freemoptions(im6o)
2267         struct ip6_moptions *im6o;
2268 {
2269         struct in6_multi_mship *imm;
2270
2271         if (im6o == NULL)
2272                 return;
2273
2274         while ((imm = im6o->im6o_memberships.lh_first) != NULL) {
2275                 LIST_REMOVE(imm, i6mm_chain);
2276                 if (imm->i6mm_maddr)
2277                         in6_delmulti(imm->i6mm_maddr);
2278                 free(imm, M_IPMADDR);
2279         }
2280         free(im6o, M_IPMOPTS);
2281 }
2282
2283 /*
2284  * Set IPv6 outgoing packet options based on advanced API.
2285  */
2286 int
2287 ip6_setpktoptions(control, opt, priv, needcopy)
2288         struct mbuf *control;
2289         struct ip6_pktopts *opt;
2290         int priv, needcopy;
2291 {
2292         struct cmsghdr *cm = 0;
2293
2294         if (control == 0 || opt == 0)
2295                 return(EINVAL);
2296
2297         init_ip6pktopts(opt);
2298
2299         /*
2300          * XXX: Currently, we assume all the optional information is stored
2301          * in a single mbuf.
2302          */
2303         if (control->m_next)
2304                 return(EINVAL);
2305
2306         for (; control->m_len; control->m_data += CMSG_ALIGN(cm->cmsg_len),
2307                      control->m_len -= CMSG_ALIGN(cm->cmsg_len)) {
2308                 cm = mtod(control, struct cmsghdr *);
2309                 if (cm->cmsg_len == 0 || cm->cmsg_len > control->m_len)
2310                         return(EINVAL);
2311                 if (cm->cmsg_level != IPPROTO_IPV6)
2312                         continue;
2313
2314                 /*
2315                  * XXX should check if RFC2292 API is mixed with 2292bis API
2316                  */
2317                 switch (cm->cmsg_type) {
2318                 case IPV6_PKTINFO:
2319                         if (cm->cmsg_len != CMSG_LEN(sizeof(struct in6_pktinfo)))
2320                                 return(EINVAL);
2321                         if (needcopy) {
2322                                 /* XXX: Is it really WAITOK? */
2323                                 opt->ip6po_pktinfo =
2324                                         malloc(sizeof(struct in6_pktinfo),
2325                                                M_IP6OPT, M_WAITOK);
2326                                 bcopy(CMSG_DATA(cm), opt->ip6po_pktinfo,
2327                                     sizeof(struct in6_pktinfo));
2328                         } else
2329                                 opt->ip6po_pktinfo =
2330                                         (struct in6_pktinfo *)CMSG_DATA(cm);
2331                         if (opt->ip6po_pktinfo->ipi6_ifindex &&
2332                             IN6_IS_ADDR_LINKLOCAL(&opt->ip6po_pktinfo->ipi6_addr))
2333                                 opt->ip6po_pktinfo->ipi6_addr.s6_addr16[1] =
2334                                         htons(opt->ip6po_pktinfo->ipi6_ifindex);
2335
2336                         if (opt->ip6po_pktinfo->ipi6_ifindex > if_index
2337                          || opt->ip6po_pktinfo->ipi6_ifindex < 0) {
2338                                 return(ENXIO);
2339                         }
2340
2341                         /*
2342                          * Check if the requested source address is indeed a
2343                          * unicast address assigned to the node, and can be
2344                          * used as the packet's source address.
2345                          */
2346                         if (!IN6_IS_ADDR_UNSPECIFIED(&opt->ip6po_pktinfo->ipi6_addr)) {
2347                                 struct in6_ifaddr *ia6;
2348                                 struct sockaddr_in6 sin6;
2349
2350                                 bzero(&sin6, sizeof(sin6));
2351                                 sin6.sin6_len = sizeof(sin6);
2352                                 sin6.sin6_family = AF_INET6;
2353                                 sin6.sin6_addr =
2354                                         opt->ip6po_pktinfo->ipi6_addr;
2355                                 ia6 = (struct in6_ifaddr *)ifa_ifwithaddr(sin6tosa(&sin6));
2356                                 if (ia6 == NULL ||
2357                                     (ia6->ia6_flags & (IN6_IFF_ANYCAST |
2358                                                        IN6_IFF_NOTREADY)) != 0)
2359                                         return(EADDRNOTAVAIL);
2360                         }
2361                         break;
2362
2363                 case IPV6_HOPLIMIT:
2364                         if (cm->cmsg_len != CMSG_LEN(sizeof(int)))
2365                                 return(EINVAL);
2366
2367                         opt->ip6po_hlim = *(int *)CMSG_DATA(cm);
2368                         if (opt->ip6po_hlim < -1 || opt->ip6po_hlim > 255)
2369                                 return(EINVAL);
2370                         break;
2371
2372                 case IPV6_NEXTHOP:
2373                         if (!priv)
2374                                 return(EPERM);
2375
2376                         if (cm->cmsg_len < sizeof(u_char) ||
2377                             /* check if cmsg_len is large enough for sa_len */
2378                             cm->cmsg_len < CMSG_LEN(*CMSG_DATA(cm)))
2379                                 return(EINVAL);
2380
2381                         if (needcopy) {
2382                                 opt->ip6po_nexthop =
2383                                         malloc(*CMSG_DATA(cm),
2384                                                M_IP6OPT, M_WAITOK);
2385                                 bcopy(CMSG_DATA(cm),
2386                                       opt->ip6po_nexthop,
2387                                       *CMSG_DATA(cm));
2388                         } else
2389                                 opt->ip6po_nexthop =
2390                                         (struct sockaddr *)CMSG_DATA(cm);
2391                         break;
2392
2393                 case IPV6_HOPOPTS:
2394                 {
2395                         struct ip6_hbh *hbh;
2396                         int hbhlen;
2397
2398                         if (cm->cmsg_len < CMSG_LEN(sizeof(struct ip6_hbh)))
2399                                 return(EINVAL);
2400                         hbh = (struct ip6_hbh *)CMSG_DATA(cm);
2401                         hbhlen = (hbh->ip6h_len + 1) << 3;
2402                         if (cm->cmsg_len != CMSG_LEN(hbhlen))
2403                                 return(EINVAL);
2404
2405                         if (needcopy) {
2406                                 opt->ip6po_hbh =
2407                                         malloc(hbhlen, M_IP6OPT, M_WAITOK);
2408                                 bcopy(hbh, opt->ip6po_hbh, hbhlen);
2409                         } else
2410                                 opt->ip6po_hbh = hbh;
2411                         break;
2412                 }
2413
2414                 case IPV6_DSTOPTS:
2415                 {
2416                         struct ip6_dest *dest, **newdest;
2417                         int destlen;
2418
2419                         if (cm->cmsg_len < CMSG_LEN(sizeof(struct ip6_dest)))
2420                                 return(EINVAL);
2421                         dest = (struct ip6_dest *)CMSG_DATA(cm);
2422                         destlen = (dest->ip6d_len + 1) << 3;
2423                         if (cm->cmsg_len != CMSG_LEN(destlen))
2424                                 return(EINVAL);
2425
2426                         /* 
2427                          * The old advacned API is ambiguous on this
2428                          * point. Our approach is to determine the
2429                          * position based according to the existence
2430                          * of a routing header. Note, however, that
2431                          * this depends on the order of the extension
2432                          * headers in the ancillary data; the 1st part
2433                          * of the destination options header must
2434                          * appear before the routing header in the
2435                          * ancillary data, too.
2436                          * RFC2292bis solved the ambiguity by
2437                          * introducing separate cmsg types.
2438                          */
2439                         if (opt->ip6po_rthdr == NULL)
2440                                 newdest = &opt->ip6po_dest1;
2441                         else
2442                                 newdest = &opt->ip6po_dest2;
2443
2444                         if (needcopy) {
2445                                 *newdest = malloc(destlen, M_IP6OPT, M_WAITOK);
2446                                 bcopy(dest, *newdest, destlen);
2447                         } else
2448                                 *newdest = dest;
2449
2450                         break;
2451                 }
2452
2453                 case IPV6_RTHDR:
2454                 {
2455                         struct ip6_rthdr *rth;
2456                         int rthlen;
2457
2458                         if (cm->cmsg_len < CMSG_LEN(sizeof(struct ip6_rthdr)))
2459                                 return(EINVAL);
2460                         rth = (struct ip6_rthdr *)CMSG_DATA(cm);
2461                         rthlen = (rth->ip6r_len + 1) << 3;
2462                         if (cm->cmsg_len != CMSG_LEN(rthlen))
2463                                 return(EINVAL);
2464
2465                         switch (rth->ip6r_type) {
2466                         case IPV6_RTHDR_TYPE_0:
2467                                 /* must contain one addr */
2468                                 if (rth->ip6r_len == 0)
2469                                         return(EINVAL);
2470                                 /* length must be even */
2471                                 if (rth->ip6r_len % 2)
2472                                         return(EINVAL);
2473                                 if (rth->ip6r_len / 2 != rth->ip6r_segleft)
2474                                         return(EINVAL);
2475                                 break;
2476                         default:
2477                                 return(EINVAL); /* not supported */
2478                         }
2479
2480                         if (needcopy) {
2481                                 opt->ip6po_rthdr = malloc(rthlen, M_IP6OPT,
2482                                                           M_WAITOK);
2483                                 bcopy(rth, opt->ip6po_rthdr, rthlen);
2484                         } else
2485                                 opt->ip6po_rthdr = rth;
2486
2487                         break;
2488                 }
2489
2490                 default:
2491                         return(ENOPROTOOPT);
2492                 }
2493         }
2494
2495         return(0);
2496 }
2497
2498 /*
2499  * Routine called from ip6_output() to loop back a copy of an IP6 multicast
2500  * packet to the input queue of a specified interface.  Note that this
2501  * calls the output routine of the loopback "driver", but with an interface
2502  * pointer that might NOT be &loif -- easier than replicating that code here.
2503  */
2504 void
2505 ip6_mloopback(ifp, m, dst)
2506         struct ifnet *ifp;
2507         struct mbuf *m;
2508         struct sockaddr_in6 *dst;
2509 {
2510         struct mbuf *copym;
2511         struct ip6_hdr *ip6;
2512
2513         copym = m_copy(m, 0, M_COPYALL);
2514         if (copym == NULL)
2515                 return;
2516
2517         /*
2518          * Make sure to deep-copy IPv6 header portion in case the data
2519          * is in an mbuf cluster, so that we can safely override the IPv6
2520          * header portion later.
2521          */
2522         if ((copym->m_flags & M_EXT) != 0 ||
2523             copym->m_len < sizeof(struct ip6_hdr)) {
2524                 copym = m_pullup(copym, sizeof(struct ip6_hdr));
2525                 if (copym == NULL)
2526                         return;
2527         }
2528
2529 #ifdef DIAGNOSTIC
2530         if (copym->m_len < sizeof(*ip6)) {
2531                 m_freem(copym);
2532                 return;
2533         }
2534 #endif
2535
2536         ip6 = mtod(copym, struct ip6_hdr *);
2537 #ifndef SCOPEDROUTING
2538         /*
2539          * clear embedded scope identifiers if necessary.
2540          * in6_clearscope will touch the addresses only when necessary.
2541          */
2542         in6_clearscope(&ip6->ip6_src);
2543         in6_clearscope(&ip6->ip6_dst);
2544 #endif
2545
2546         (void)if_simloop(ifp, copym, dst->sin6_family, NULL);
2547 }
2548
2549 /*
2550  * Chop IPv6 header off from the payload.
2551  */
2552 static int
2553 ip6_splithdr(m, exthdrs)
2554         struct mbuf *m;
2555         struct ip6_exthdrs *exthdrs;
2556 {
2557         struct mbuf *mh;
2558         struct ip6_hdr *ip6;
2559
2560         ip6 = mtod(m, struct ip6_hdr *);
2561         if (m->m_len > sizeof(*ip6)) {
2562                 MGETHDR(mh, M_DONTWAIT, MT_HEADER);
2563                 if (mh == 0) {
2564                         m_freem(m);
2565                         return ENOBUFS;
2566                 }
2567                 M_MOVE_PKTHDR(mh, m);
2568                 MH_ALIGN(mh, sizeof(*ip6));
2569                 m->m_len -= sizeof(*ip6);
2570                 m->m_data += sizeof(*ip6);
2571                 mh->m_next = m;
2572                 m = mh;
2573                 m->m_len = sizeof(*ip6);
2574                 bcopy((caddr_t)ip6, mtod(m, caddr_t), sizeof(*ip6));
2575         }
2576         exthdrs->ip6e_ip6 = m;
2577         return 0;
2578 }
2579
2580 /*
2581  * Compute IPv6 extension header length.
2582  */
2583 int
2584 ip6_optlen(in6p)
2585         struct in6pcb *in6p;
2586 {
2587         int len;
2588
2589         if (!in6p->in6p_outputopts)
2590                 return 0;
2591
2592         len = 0;
2593 #define elen(x) \
2594     (((struct ip6_ext *)(x)) ? (((struct ip6_ext *)(x))->ip6e_len + 1) << 3 : 0)
2595
2596         len += elen(in6p->in6p_outputopts->ip6po_hbh);
2597         if (in6p->in6p_outputopts->ip6po_rthdr)
2598                 /* dest1 is valid with rthdr only */
2599                 len += elen(in6p->in6p_outputopts->ip6po_dest1);
2600         len += elen(in6p->in6p_outputopts->ip6po_rthdr);
2601         len += elen(in6p->in6p_outputopts->ip6po_dest2);
2602         return len;
2603 #undef elen
2604 }