xref: /dragonfly/usr.sbin/rtadvd/if.c (revision e62ef63cd8bf9a1124d7110b8e05ff70a95d58e1)
1 /*        $FreeBSD: stable/10/usr.sbin/rtadvd/if.c 255156 2013-09-02 20:44:19Z hrs $      */
2 /*        $KAME: if.c,v 1.17 2001/01/21 15:27:30 itojun Exp $         */
3 
4 /*
5  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
6  * Copyright (C) 2011 Hiroki Sato <hrs@FreeBSD.org>
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 #include <sys/param.h>
35 #include <sys/socket.h>
36 #include <sys/sysctl.h>
37 #include <sys/ioctl.h>
38 #include <net/if.h>
39 #include <net/if_dl.h>
40 #include <net/if_types.h>
41 #include <net/if_var.h>
42 #include <net/ethernet.h>
43 #include <net/route.h>
44 #include <netinet/in.h>
45 #include <netinet/in_var.h>
46 #include <netinet/ip6.h>
47 #include <netinet/icmp6.h>
48 #include <netinet6/nd6.h>
49 #include <unistd.h>
50 #include <errno.h>
51 #include <netdb.h>
52 #include <stdlib.h>
53 #include <string.h>
54 #include <syslog.h>
55 
56 #include "pathnames.h"
57 #include "rtadvd.h"
58 #include "if.h"
59 
60 #define ROUNDUP(a, size)                                              \
61           (((a) & ((size)-1)) ? (1 + ((a) | ((size)-1))) : (a))
62 
63 #define   NEXT_SA(ap)                                                                     \
64           (ap) = (struct sockaddr *)((caddr_t)(ap) +                            \
65               ((ap)->sa_len ? ROUNDUP((ap)->sa_len, sizeof(u_long)) : \
66               sizeof(u_long)))
67 
68 struct sockaddr_in6 sin6_linklocal_allnodes = {
69         .sin6_len =     sizeof(sin6_linklocal_allnodes),
70         .sin6_family =  AF_INET6,
71         .sin6_addr =    IN6ADDR_LINKLOCAL_ALLNODES_INIT,
72 };
73 
74 struct sockaddr_in6 sin6_linklocal_allrouters = {
75         .sin6_len =     sizeof(sin6_linklocal_allrouters),
76         .sin6_family =  AF_INET6,
77         .sin6_addr =    IN6ADDR_LINKLOCAL_ALLROUTERS_INIT,
78 };
79 
80 struct sockaddr_in6 sin6_sitelocal_allrouters = {
81         .sin6_len =     sizeof(sin6_sitelocal_allrouters),
82         .sin6_family =  AF_INET6,
83         .sin6_addr =    IN6ADDR_SITELOCAL_ALLROUTERS_INIT,
84 };
85 
86 struct sockinfo sock = { .si_fd = -1, .si_name = NULL };
87 struct sockinfo rtsock = { .si_fd = -1, .si_name = NULL };
88 struct sockinfo ctrlsock = { .si_fd = -1, .si_name = _PATH_CTRL_SOCK };
89 
90 char *mcastif;
91 
92 static void                   get_rtaddrs(int, struct sockaddr *,
93                                   struct sockaddr **);
94 static struct if_msghdr       *get_next_msghdr(struct if_msghdr *,
95                                   struct if_msghdr *);
96 
97 static void
get_rtaddrs(int addrs,struct sockaddr * sa,struct sockaddr ** rti_info)98 get_rtaddrs(int addrs, struct sockaddr *sa, struct sockaddr **rti_info)
99 {
100           int i;
101 
102           for (i = 0; i < RTAX_MAX; i++) {
103                     if (addrs & (1 << i)) {
104                               rti_info[i] = sa;
105                               NEXT_SA(sa);
106                     }
107                     else
108                               rti_info[i] = NULL;
109           }
110 }
111 
112 #define ROUNDUP8(a) (1 + (((a) - 1) | 7))
113 int
lladdropt_length(struct sockaddr_dl * sdl)114 lladdropt_length(struct sockaddr_dl *sdl)
115 {
116           switch (sdl->sdl_type) {
117           case IFT_ETHER:
118                     return (ROUNDUP8(ETHER_ADDR_LEN + 2));
119           default:
120                     return (0);
121           }
122 }
123 
124 void
lladdropt_fill(struct sockaddr_dl * sdl,struct nd_opt_hdr * ndopt)125 lladdropt_fill(struct sockaddr_dl *sdl, struct nd_opt_hdr *ndopt)
126 {
127           char *addr;
128 
129           ndopt->nd_opt_type = ND_OPT_SOURCE_LINKADDR; /* fixed */
130 
131           switch (sdl->sdl_type) {
132           case IFT_ETHER:
133                     ndopt->nd_opt_len = (ROUNDUP8(ETHER_ADDR_LEN + 2)) >> 3;
134                     addr = (char *)(ndopt + 1);
135                     memcpy(addr, LLADDR(sdl), ETHER_ADDR_LEN);
136                     break;
137           default:
138                     syslog(LOG_ERR, "<%s> unsupported link type(%d)",
139                         __func__, sdl->sdl_type);
140                     exit(1);
141           }
142 
143           return;
144 }
145 
146 int
rtbuf_len(void)147 rtbuf_len(void)
148 {
149           size_t len;
150           int mib[6] = {CTL_NET, AF_ROUTE, 0, AF_INET6, NET_RT_DUMP, 0};
151 
152           if (sysctl(mib, 6, NULL, &len, NULL, 0) < 0)
153                     return (-1);
154 
155           return (len);
156 }
157 
158 #define FILTER_MATCH(type, filter) ((0x1 << type) & filter)
159 #define SIN6(s) ((struct sockaddr_in6 *)(s))
160 #define SDL(s) ((struct sockaddr_dl *)(s))
161 char *
get_next_msg(char * buf,char * lim,int ifindex,size_t * lenp,int filter)162 get_next_msg(char *buf, char *lim, int ifindex, size_t *lenp, int filter)
163 {
164           struct rt_msghdr *rtm;
165           struct ifa_msghdr *ifam;
166           struct sockaddr *sa, *dst, *gw, *ifa, *rti_info[RTAX_MAX];
167 
168           *lenp = 0;
169           for (rtm = (struct rt_msghdr *)buf;
170                rtm < (struct rt_msghdr *)lim;
171                rtm = (struct rt_msghdr *)(((char *)rtm) + rtm->rtm_msglen)) {
172                     /* just for safety */
173                     if (!rtm->rtm_msglen) {
174                               syslog(LOG_WARNING, "<%s> rtm_msglen is 0 "
175                                   "(buf=%p lim=%p rtm=%p)", __func__,
176                                   buf, lim, rtm);
177                               break;
178                     }
179                     if (((struct rt_msghdr *)buf)->rtm_version != RTM_VERSION) {
180                               syslog(LOG_WARNING,
181                                   "<%s> routing message version mismatch "
182                                   "(buf=%p lim=%p rtm=%p)", __func__,
183                                   buf, lim, rtm);
184                               continue;
185                     }
186 
187                     if (FILTER_MATCH(rtm->rtm_type, filter) == 0)
188                               continue;
189 
190                     switch (rtm->rtm_type) {
191                     case RTM_GET:
192                     case RTM_ADD:
193                     case RTM_DELETE:
194                               /* address related checks */
195                               sa = (struct sockaddr *)(rtm + 1);
196                               get_rtaddrs(rtm->rtm_addrs, sa, rti_info);
197                               if ((dst = rti_info[RTAX_DST]) == NULL ||
198                                   dst->sa_family != AF_INET6)
199                                         continue;
200 
201                               if (IN6_IS_ADDR_LINKLOCAL(&SIN6(dst)->sin6_addr) ||
202                                   IN6_IS_ADDR_MULTICAST(&SIN6(dst)->sin6_addr))
203                                         continue;
204 
205                               if ((gw = rti_info[RTAX_GATEWAY]) == NULL ||
206                                   gw->sa_family != AF_LINK)
207                                         continue;
208                               if (ifindex && SDL(gw)->sdl_index != ifindex)
209                                         continue;
210 
211                               if (rti_info[RTAX_NETMASK] == NULL)
212                                         continue;
213 
214                               /* found */
215                               *lenp = rtm->rtm_msglen;
216                               return (char *)rtm;
217                               /* NOTREACHED */
218                     case RTM_NEWADDR:
219                     case RTM_DELADDR:
220                               ifam = (struct ifa_msghdr *)rtm;
221 
222                               /* address related checks */
223                               sa = (struct sockaddr *)(ifam + 1);
224                               get_rtaddrs(ifam->ifam_addrs, sa, rti_info);
225                               if ((ifa = rti_info[RTAX_IFA]) == NULL ||
226                                   (ifa->sa_family != AF_INET &&
227                                    ifa->sa_family != AF_INET6))
228                                         continue;
229 
230                               if (ifa->sa_family == AF_INET6 &&
231                                   (IN6_IS_ADDR_LINKLOCAL(&SIN6(ifa)->sin6_addr) ||
232                                    IN6_IS_ADDR_MULTICAST(&SIN6(ifa)->sin6_addr)))
233                                         continue;
234 
235                               if (ifindex && ifam->ifam_index != ifindex)
236                                         continue;
237 
238                               /* found */
239                               *lenp = ifam->ifam_msglen;
240                               return (char *)rtm;
241                               /* NOTREACHED */
242                     case RTM_IFINFO:
243                     case RTM_IFANNOUNCE:
244                               /* found */
245                               *lenp = rtm->rtm_msglen;
246                               return (char *)rtm;
247                               /* NOTREACHED */
248                     }
249           }
250 
251           return ((char *)rtm);
252 }
253 #undef FILTER_MATCH
254 
255 struct in6_addr *
get_addr(char * buf)256 get_addr(char *buf)
257 {
258           struct rt_msghdr *rtm = (struct rt_msghdr *)buf;
259           struct sockaddr *sa, *rti_info[RTAX_MAX];
260 
261           sa = (struct sockaddr *)(rtm + 1);
262           get_rtaddrs(rtm->rtm_addrs, sa, rti_info);
263 
264           return (&SIN6(rti_info[RTAX_DST])->sin6_addr);
265 }
266 
267 int
get_rtm_ifindex(char * buf)268 get_rtm_ifindex(char *buf)
269 {
270           struct rt_msghdr *rtm = (struct rt_msghdr *)buf;
271           struct sockaddr *sa, *rti_info[RTAX_MAX];
272 
273           sa = (struct sockaddr *)(rtm + 1);
274           get_rtaddrs(rtm->rtm_addrs, sa, rti_info);
275 
276           return (((struct sockaddr_dl *)rti_info[RTAX_GATEWAY])->sdl_index);
277 }
278 
279 int
get_prefixlen(char * buf)280 get_prefixlen(char *buf)
281 {
282           struct rt_msghdr *rtm = (struct rt_msghdr *)buf;
283           struct sockaddr *sa, *rti_info[RTAX_MAX];
284           char *p, *lim;
285 
286           sa = (struct sockaddr *)(rtm + 1);
287           get_rtaddrs(rtm->rtm_addrs, sa, rti_info);
288           sa = rti_info[RTAX_NETMASK];
289 
290           p = (char *)(&SIN6(sa)->sin6_addr);
291           lim = (char *)sa + sa->sa_len;
292           return prefixlen(p, lim);
293 }
294 
295 int
prefixlen(unsigned char * p,unsigned char * lim)296 prefixlen(unsigned char *p, unsigned char *lim)
297 {
298           int masklen;
299 
300           for (masklen = 0; p < lim; p++) {
301                     switch (*p) {
302                     case 0xff:
303                               masklen += 8;
304                               break;
305                     case 0xfe:
306                               masklen += 7;
307                               break;
308                     case 0xfc:
309                               masklen += 6;
310                               break;
311                     case 0xf8:
312                               masklen += 5;
313                               break;
314                     case 0xf0:
315                               masklen += 4;
316                               break;
317                     case 0xe0:
318                               masklen += 3;
319                               break;
320                     case 0xc0:
321                               masklen += 2;
322                               break;
323                     case 0x80:
324                               masklen += 1;
325                               break;
326                     case 0x00:
327                               break;
328                     default:
329                               return (-1);
330                     }
331           }
332 
333           return (masklen);
334 }
335 
336 struct ifinfo *
update_persist_ifinfo(struct ifilist_head_t * ifi_head,const char * ifname)337 update_persist_ifinfo(struct ifilist_head_t *ifi_head, const char *ifname)
338 {
339           struct ifinfo *ifi;
340           int ifindex;
341 
342           ifi = NULL;
343           ifindex = if_nametoindex(ifname);
344           TAILQ_FOREACH(ifi, ifi_head, ifi_next) {
345                     if (ifindex != 0) {
346                               if (ifindex == ifi->ifi_ifindex)
347                                         break;
348                     } else {
349                               if (strncmp(ifname, ifi->ifi_ifname,
350                                         sizeof(ifi->ifi_ifname)) == 0)
351                                         break;
352                     }
353           }
354 
355           if (ifi == NULL) {
356                     /* A new ifinfo element is needed. */
357                     syslog(LOG_DEBUG, "<%s> new entry: %s", __func__,
358                         ifname);
359 
360                     ELM_MALLOC(ifi, exit(1));
361                     ifi->ifi_ifindex = 0;
362                     strncpy(ifi->ifi_ifname, ifname, sizeof(ifi->ifi_ifname)-1);
363                     ifi->ifi_ifname[sizeof(ifi->ifi_ifname)-1] = '\0';
364                     ifi->ifi_rainfo = NULL;
365                     ifi->ifi_state = IFI_STATE_UNCONFIGURED;
366                     TAILQ_INSERT_TAIL(ifi_head, ifi, ifi_next);
367           }
368 
369           ifi->ifi_persist = 1;
370 
371           syslog(LOG_DEBUG, "<%s> %s is marked PERSIST", __func__,
372               ifi->ifi_ifname);
373           syslog(LOG_DEBUG, "<%s> %s is state = %d", __func__,
374               ifi->ifi_ifname, ifi->ifi_state);
375           return (ifi);
376 }
377 
378 int
update_ifinfo_nd_flags(struct ifinfo * ifi)379 update_ifinfo_nd_flags(struct ifinfo *ifi)
380 {
381           struct in6_ndireq nd;
382           int s;
383           int error;
384 
385           if ((s = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) {
386                     syslog(LOG_ERR,
387                         "<%s> socket() failed.", __func__);
388                     return (1);
389           }
390           /* ND flags */
391           memset(&nd, 0, sizeof(nd));
392           strncpy(nd.ifname, ifi->ifi_ifname,
393               sizeof(nd.ifname));
394           error = ioctl(s, SIOCGIFINFO_IN6, (caddr_t)&nd);
395           if (error) {
396                     close(s);
397                     if (errno != EPFNOSUPPORT)
398                               syslog(LOG_ERR, "<%s> ioctl() failed.", __func__);
399                     return (1);
400           }
401           ifi->ifi_nd_flags = nd.ndi.flags;
402           close(s);
403 
404           return (0);
405 }
406 
407 struct ifinfo *
update_ifinfo(struct ifilist_head_t * ifi_head,int ifindex)408 update_ifinfo(struct ifilist_head_t *ifi_head, int ifindex)
409 {
410           struct if_msghdr *ifm;
411           struct ifinfo *ifi = NULL;
412           struct sockaddr *sa;
413           struct sockaddr *rti_info[RTAX_MAX];
414           char *msg;
415           size_t len;
416           char *lim;
417           int mib[] = { CTL_NET, PF_ROUTE, 0, AF_INET6, NET_RT_IFLIST, 0 };
418           int error;
419 
420           syslog(LOG_DEBUG, "<%s> enter", __func__);
421 
422           if (sysctl(mib, NELEM(mib), NULL, &len, NULL, 0) <
423               0) {
424                     syslog(LOG_ERR,
425                         "<%s> sysctl: NET_RT_IFLIST size get failed", __func__);
426                     exit(1);
427           }
428           if ((msg = malloc(len)) == NULL) {
429                     syslog(LOG_ERR, "<%s> malloc failed", __func__);
430                     exit(1);
431           }
432           if (sysctl(mib, NELEM(mib), msg, &len, NULL, 0) <
433               0) {
434                     syslog(LOG_ERR,
435                         "<%s> sysctl: NET_RT_IFLIST get failed", __func__);
436                     exit(1);
437           }
438 
439           lim = msg + len;
440           for (ifm = (struct if_msghdr *)msg;
441                ifm != NULL && ifm < (struct if_msghdr *)lim;
442                ifm = get_next_msghdr(ifm,(struct if_msghdr *)lim)) {
443                     int ifi_new;
444 
445                     syslog(LOG_DEBUG, "<%s> ifm = %p, lim = %p, diff = %zu",
446                         __func__, ifm, lim, (char *)lim - (char *)ifm);
447 
448                     if (ifm->ifm_version != RTM_VERSION) {
449                               syslog(LOG_ERR,
450                                   "<%s> ifm_vesrion mismatch", __func__);
451                               exit(1);
452                     }
453                     if (ifm->ifm_msglen == 0) {
454                               syslog(LOG_WARNING,
455                                   "<%s> ifm_msglen is 0", __func__);
456                               free(msg);
457                               return (NULL);
458                     }
459 
460                     ifi_new = 0;
461                     if (ifm->ifm_type == RTM_IFINFO) {
462                               struct ifreq ifr;
463                               int s;
464                               char ifname[IFNAMSIZ];
465 
466                               syslog(LOG_DEBUG, "<%s> RTM_IFINFO found. "
467                                   "ifm_index = %d, ifindex = %d",
468                                   __func__, ifm->ifm_index, ifindex);
469 
470                               /* when ifindex is specified */
471                               if (ifindex != UPDATE_IFINFO_ALL &&
472                                   ifindex != ifm->ifm_index)
473                                         continue;
474 
475                               /* lookup an entry with the same ifindex */
476                               TAILQ_FOREACH(ifi, ifi_head, ifi_next) {
477                                         if (ifm->ifm_index == ifi->ifi_ifindex)
478                                                   break;
479                                         if_indextoname(ifm->ifm_index, ifname);
480                                         if (strncmp(ifname, ifi->ifi_ifname,
481                                                   sizeof(ifname)) == 0)
482                                                   break;
483                               }
484                               if (ifi == NULL) {
485                                         syslog(LOG_DEBUG,
486                                             "<%s> new entry for idx=%d",
487                                             __func__, ifm->ifm_index);
488                                         ELM_MALLOC(ifi, exit(1));
489                                         ifi->ifi_rainfo = NULL;
490                                         ifi->ifi_state = IFI_STATE_UNCONFIGURED;
491                                         ifi->ifi_persist = 0;
492                                         ifi_new = 1;
493                               }
494                               /* ifindex */
495                               ifi->ifi_ifindex = ifm->ifm_index;
496 
497                               /* ifname */
498                               if_indextoname(ifm->ifm_index, ifi->ifi_ifname);
499                               if (ifi->ifi_ifname == NULL) {
500                                         syslog(LOG_WARNING,
501                                             "<%s> ifname not found (idx=%d)",
502                                             __func__, ifm->ifm_index);
503                                         if (ifi_new)
504                                                   free(ifi);
505                                         continue;
506                               }
507 
508                               if ((s = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) {
509                                         syslog(LOG_ERR,
510                                             "<%s> socket() failed.", __func__);
511                                         if (ifi_new)
512                                                   free(ifi);
513                                         continue;
514                               }
515 
516                               /* MTU  */
517                               ifi->ifi_phymtu = ifm->ifm_data.ifi_mtu;
518                               if (ifi->ifi_phymtu == 0) {
519                                         memset(&ifr, 0, sizeof(ifr));
520                                         ifr.ifr_addr.sa_family = AF_INET6;
521                                         strncpy(ifr.ifr_name, ifi->ifi_ifname,
522                                             sizeof(ifr.ifr_name));
523                                         error = ioctl(s, SIOCGIFMTU, (caddr_t)&ifr);
524                                         if (error) {
525                                                   close(s);
526                                                   syslog(LOG_ERR,
527                                                       "<%s> ioctl() failed.",
528                                                       __func__);
529                                                   if (ifi_new)
530                                                             free(ifi);
531                                                   continue;
532                                         }
533                                         ifi->ifi_phymtu = ifr.ifr_mtu;
534                                         if (ifi->ifi_phymtu == 0) {
535                                                   syslog(LOG_WARNING,
536                                                       "<%s> no interface mtu info"
537                                                       " on %s.  %d will be used.",
538                                                       __func__, ifi->ifi_ifname,
539                                                       IPV6_MMTU);
540                                                   ifi->ifi_phymtu = IPV6_MMTU;
541                                         }
542                               }
543                               close(s);
544 
545                               /* ND flags */
546                               error = update_ifinfo_nd_flags(ifi);
547                               if (error) {
548                                         if (ifi_new)
549                                                   free(ifi);
550                                         continue;
551                               }
552 
553                               /* SDL */
554                               sa = (struct sockaddr *)(ifm + 1);
555                               get_rtaddrs(ifm->ifm_addrs, sa, rti_info);
556                               if ((sa = rti_info[RTAX_IFP]) != NULL) {
557                                         if (sa->sa_family == AF_LINK) {
558                                                   memcpy(&ifi->ifi_sdl,
559                                                       (struct sockaddr_dl *)sa,
560                                                       sizeof(ifi->ifi_sdl));
561                                         }
562                               } else
563                                         memset(&ifi->ifi_sdl, 0,
564                                             sizeof(ifi->ifi_sdl));
565 
566                               /* flags */
567                               ifi->ifi_flags = ifm->ifm_flags;
568 
569                               /* type */
570                               ifi->ifi_type = ifm->ifm_type;
571                     } else {
572                               syslog(LOG_ERR,
573                                   "out of sync parsing NET_RT_IFLIST\n"
574                                   "expected %d, got %d\n msglen = %d\n",
575                                   RTM_IFINFO, ifm->ifm_type, ifm->ifm_msglen);
576                               exit(1);
577                     }
578 
579                     if (ifi_new) {
580                               syslog(LOG_DEBUG,
581                                   "<%s> adding %s(idx=%d) to ifilist",
582                                   __func__, ifi->ifi_ifname, ifi->ifi_ifindex);
583                               TAILQ_INSERT_TAIL(ifi_head, ifi, ifi_next);
584                     }
585           }
586           free(msg);
587 
588           if (mcastif != NULL) {
589                     error = sock_mc_rr_update(&sock, mcastif);
590                     if (error)
591                               exit(1);
592           }
593 
594           return (ifi);
595 }
596 
597 static struct if_msghdr *
get_next_msghdr(struct if_msghdr * ifm,struct if_msghdr * lim)598 get_next_msghdr(struct if_msghdr *ifm, struct if_msghdr *lim)
599 {
600           struct ifa_msghdr *ifam;
601 
602           for (ifam = (struct ifa_msghdr *)((char *)ifm + ifm->ifm_msglen);
603                ifam < (struct ifa_msghdr *)lim;
604                ifam = (struct ifa_msghdr *)((char *)ifam + ifam->ifam_msglen)) {
605                     if (!ifam->ifam_msglen) {
606                               syslog(LOG_WARNING,
607                                   "<%s> ifa_msglen is 0", __func__);
608                               return (NULL);
609                     }
610                     if (ifam->ifam_type != RTM_NEWADDR)
611                               break;
612           }
613 
614           return ((struct if_msghdr *)ifam);
615 }
616 
617 int
getinet6sysctl(int code)618 getinet6sysctl(int code)
619 {
620           int mib[] = { CTL_NET, PF_INET6, IPPROTO_IPV6, 0 };
621           int value;
622           size_t size;
623 
624           mib[3] = code;
625           size = sizeof(value);
626           if (sysctl(mib, NELEM(mib), &value, &size, NULL, 0)
627               < 0) {
628                     syslog(LOG_ERR, "<%s>: failed to get ip6 sysctl(%d): %s",
629                         __func__, code,
630                         strerror(errno));
631                     return (-1);
632           }
633           else
634                     return (value);
635 }
636 
637 
638 int
sock_mc_join(struct sockinfo * s,int ifindex)639 sock_mc_join(struct sockinfo *s, int ifindex)
640 {
641           struct ipv6_mreq mreq;
642           char ifname[IFNAMSIZ];
643 
644           syslog(LOG_DEBUG, "<%s> enter", __func__);
645 
646           if (ifindex == 0)
647                     return (1);
648 
649           /*
650            * join all routers multicast address on each advertising
651            * interface.
652            */
653           memset(&mreq, 0, sizeof(mreq));
654           /* XXX */
655           memcpy(&mreq.ipv6mr_multiaddr.s6_addr,
656               &sin6_linklocal_allrouters.sin6_addr,
657               sizeof(mreq.ipv6mr_multiaddr.s6_addr));
658 
659           mreq.ipv6mr_interface = ifindex;
660           if (setsockopt(s->si_fd, IPPROTO_IPV6, IPV6_JOIN_GROUP, &mreq,
661                     sizeof(mreq)) < 0) {
662                     syslog(LOG_ERR,
663                         "<%s> IPV6_JOIN_GROUP(link) on %s: %s",
664                         __func__, if_indextoname(ifindex, ifname),
665                         strerror(errno));
666                     return (1);
667           }
668           syslog(LOG_DEBUG,
669               "<%s> %s: join link-local all-routers MC group",
670               __func__, if_indextoname(ifindex, ifname));
671 
672           return (0);
673 }
674 
675 int
sock_mc_leave(struct sockinfo * s,int ifindex)676 sock_mc_leave(struct sockinfo *s, int ifindex)
677 {
678           struct ipv6_mreq mreq;
679           char ifname[IFNAMSIZ];
680 
681           syslog(LOG_DEBUG, "<%s> enter", __func__);
682 
683           if (ifindex == 0)
684                     return (1);
685 
686           /*
687            * join all routers multicast address on each advertising
688            * interface.
689            */
690 
691           memset(&mreq, 0, sizeof(mreq));
692           /* XXX */
693           memcpy(&mreq.ipv6mr_multiaddr.s6_addr,
694               &sin6_linklocal_allrouters.sin6_addr,
695               sizeof(mreq.ipv6mr_multiaddr.s6_addr));
696 
697           mreq.ipv6mr_interface = ifindex;
698           if (setsockopt(s->si_fd, IPPROTO_IPV6, IPV6_LEAVE_GROUP, &mreq,
699                     sizeof(mreq)) < 0) {
700                     syslog(LOG_ERR,
701                         "<%s> IPV6_JOIN_LEAVE(link) on %s: %s",
702                         __func__, if_indextoname(ifindex, ifname),
703                         strerror(errno));
704                     return (1);
705           }
706           syslog(LOG_DEBUG,
707               "<%s> %s: leave link-local all-routers MC group",
708               __func__, if_indextoname(ifindex, ifname));
709 
710           return (0);
711 }
712 
713 int
sock_mc_rr_update(struct sockinfo * s,char * mif)714 sock_mc_rr_update(struct sockinfo *s, char *mif)
715 {
716           struct ipv6_mreq mreq;
717 
718           syslog(LOG_DEBUG, "<%s> enter", __func__);
719 
720           if (mif == NULL)
721                     return (1);
722           /*
723            * When attending router renumbering, join all-routers site-local
724            * multicast group.
725            */
726           /* XXX */
727           memcpy(&mreq.ipv6mr_multiaddr.s6_addr,
728               &sin6_sitelocal_allrouters.sin6_addr,
729               sizeof(mreq.ipv6mr_multiaddr.s6_addr));
730           if ((mreq.ipv6mr_interface = if_nametoindex(mif)) == 0) {
731                     syslog(LOG_ERR,
732                         "<%s> invalid interface: %s",
733                         __func__, mif);
734                     return (1);
735           }
736 
737           if (setsockopt(s->si_fd, IPPROTO_IPV6, IPV6_JOIN_GROUP,
738                     &mreq, sizeof(mreq)) < 0) {
739                     syslog(LOG_ERR,
740                         "<%s> IPV6_JOIN_GROUP(site) on %s: %s",
741                         __func__, mif, strerror(errno));
742                     return (1);
743           }
744 
745           syslog(LOG_DEBUG,
746               "<%s> %s: join site-local all-routers MC group",
747               __func__, mif);
748 
749           return (0);
750 }
751