1 /* $OpenBSD: in6_ifattach.c,v 1.39 2005/05/23 20:10:14 mpf Exp $ */
2 /* $KAME: in6_ifattach.c,v 1.124 2001/07/18 08:32:51 jinmei Exp $ */
3
4 /*
5 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of the project nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 */
32
33 #include <sys/param.h>
34 #include <sys/systm.h>
35 #include <sys/malloc.h>
36 #include <sys/socket.h>
37 #include <sys/sockio.h>
38 #include <sys/kernel.h>
39 #include <sys/syslog.h>
40
41 #include <syskern/md5.h>
42
43 #include <net/if.h>
44 #include <net/if_dl.h>
45 #include <net/if_types.h>
46 #include <net/route.h>
47
48 #include <netinet/in.h>
49 #include <netinet/in_var.h>
50 #include <netinet/if_ether.h>
51
52 #include <netinet/ip6.h>
53 #include <netinet6/ip6_var.h>
54 #include <netinet6/in6_ifattach.h>
55 #include <netinet6/ip6_var.h>
56 #include <netinet6/nd6.h>
57 #include <netinet6/ip6_mroute.h>
58
59 unsigned long in6_maxmtu = 0;
60
61 int ip6_auto_linklocal = 1; /* enable by default */
62
63 static int get_rand_ifid(struct ifnet *, struct in6_addr *);
64 static int get_hw_ifid(struct ifnet *, struct in6_addr *);
65 static int get_ifid(struct ifnet *, struct ifnet *, struct in6_addr *);
66 static int in6_ifattach_linklocal(struct ifnet *, struct ifnet *);
67 static int in6_ifattach_loopback(struct ifnet *);
68
69 #define EUI64_GBIT 0x01
70 #define EUI64_UBIT 0x02
71 #define EUI64_TO_IFID(in6) do {(in6)->s6_addr[8] ^= EUI64_UBIT; } while (0)
72 #define EUI64_GROUP(in6) ((in6)->s6_addr[8] & EUI64_GBIT)
73 #define EUI64_INDIVIDUAL(in6) (!EUI64_GROUP(in6))
74 #define EUI64_LOCAL(in6) ((in6)->s6_addr[8] & EUI64_UBIT)
75 #define EUI64_UNIVERSAL(in6) (!EUI64_LOCAL(in6))
76
77 #define IFID_LOCAL(in6) (!EUI64_LOCAL(in6))
78 #define IFID_UNIVERSAL(in6) (!EUI64_UNIVERSAL(in6))
79
80 /*
81 * Generate a last-resort interface identifier, when the machine has no
82 * IEEE802/EUI64 address sources.
83 * The goal here is to get an interface identifier that is
84 * (1) random enough and (2) does not change across reboot.
85 * We currently use MD5(hostname) for it.
86 */
87 static int
get_rand_ifid(ifp,in6)88 get_rand_ifid(ifp, in6)
89 struct ifnet *ifp;
90 struct in6_addr *in6; /* upper 64bits are preserved */
91 {
92 MD5_CTX ctxt;
93 u_int8_t digest[16];
94
95 #if 0
96 /* we need at least several letters as seed for ifid */
97 if (hostnamelen < 3)
98 return -1;
99 #endif
100
101 /* generate 8 bytes of pseudo-random value. */
102 bzero(&ctxt, sizeof(ctxt));
103 MD5Init(&ctxt);
104 MD5Update(&ctxt, hostname, hostnamelen);
105 MD5Final(digest, &ctxt);
106
107 /* assumes sizeof(digest) > sizeof(ifid) */
108 bcopy(digest, &in6->s6_addr[8], 8);
109
110 /* make sure to set "u" bit to local, and "g" bit to individual. */
111 in6->s6_addr[8] &= ~EUI64_GBIT; /* g bit to "individual" */
112 in6->s6_addr[8] |= EUI64_UBIT; /* u bit to "local" */
113
114 /* convert EUI64 into IPv6 interface identifier */
115 EUI64_TO_IFID(in6);
116
117 return 0;
118 }
119
120 /*
121 * Get interface identifier for the specified interface.
122 * XXX assumes single sockaddr_dl (AF_LINK address) per an interface
123 */
124 static int
get_hw_ifid(ifp,in6)125 get_hw_ifid(ifp, in6)
126 struct ifnet *ifp;
127 struct in6_addr *in6; /* upper 64bits are preserved */
128 {
129 struct ifaddr *ifa;
130 struct sockaddr_dl *sdl;
131 char *addr;
132 size_t addrlen;
133 static u_int8_t allzero[8] = { 0, 0, 0, 0, 0, 0, 0, 0 };
134 static u_int8_t allone[8] =
135 { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
136
137 for (ifa = ifp->if_addrlist.tqh_first;
138 ifa;
139 ifa = ifa->ifa_list.tqe_next)
140 {
141 if (ifa->ifa_addr->sa_family != AF_LINK)
142 continue;
143 sdl = (struct sockaddr_dl *)ifa->ifa_addr;
144 if (sdl == NULL)
145 continue;
146 if (sdl->sdl_alen == 0)
147 continue;
148
149 goto found;
150 }
151
152 return -1;
153
154 found:
155 addr = LLADDR(sdl);
156 addrlen = sdl->sdl_alen;
157
158 switch (ifp->if_type) {
159 case IFT_IEEE1394:
160 case IFT_IEEE80211:
161 /* IEEE1394 uses 16byte length address starting with EUI64 */
162 if (addrlen > 8)
163 addrlen = 8;
164 break;
165 default:
166 break;
167 }
168
169 /* get EUI64 */
170 switch (ifp->if_type) {
171 /* IEEE802/EUI64 cases - what others? */
172 case IFT_ETHER:
173 case IFT_FDDI:
174 case IFT_ATM:
175 case IFT_IEEE1394:
176 case IFT_IEEE80211:
177 /* look at IEEE802/EUI64 only */
178 if (addrlen != 8 && addrlen != 6)
179 return -1;
180
181 /*
182 * check for invalid MAC address - on bsdi, we see it a lot
183 * since wildboar configures all-zero MAC on pccard before
184 * card insertion.
185 */
186 if (bcmp(addr, allzero, addrlen) == 0)
187 return -1;
188 if (bcmp(addr, allone, addrlen) == 0)
189 return -1;
190
191 /* make EUI64 address */
192 if (addrlen == 8)
193 bcopy(addr, &in6->s6_addr[8], 8);
194 else if (addrlen == 6) {
195 in6->s6_addr[8] = addr[0];
196 in6->s6_addr[9] = addr[1];
197 in6->s6_addr[10] = addr[2];
198 in6->s6_addr[11] = 0xff;
199 in6->s6_addr[12] = 0xfe;
200 in6->s6_addr[13] = addr[3];
201 in6->s6_addr[14] = addr[4];
202 in6->s6_addr[15] = addr[5];
203 }
204 break;
205
206 case IFT_ARCNET:
207 if (addrlen != 1)
208 return -1;
209 if (!addr[0])
210 return -1;
211
212 bzero(&in6->s6_addr[8], 8);
213 in6->s6_addr[15] = addr[0];
214
215 /*
216 * due to insufficient bitwidth, we mark it local.
217 */
218 in6->s6_addr[8] &= ~EUI64_GBIT; /* g bit to "individual" */
219 in6->s6_addr[8] |= EUI64_UBIT; /* u bit to "local" */
220 break;
221
222 case IFT_GIF:
223 /*
224 * RFC2893 says: "SHOULD use IPv4 address as ifid source".
225 * however, IPv4 address is not very suitable as unique
226 * identifier source (can be renumbered).
227 * we don't do this.
228 */
229 return -1;
230
231 default:
232 return -1;
233 }
234
235 /* sanity check: g bit must not indicate "group" */
236 if (EUI64_GROUP(in6))
237 return -1;
238
239 /* convert EUI64 into IPv6 interface identifier */
240 EUI64_TO_IFID(in6);
241
242 /*
243 * sanity check: ifid must not be all zero, avoid conflict with
244 * subnet router anycast
245 */
246 if ((in6->s6_addr[8] & ~(EUI64_GBIT | EUI64_UBIT)) == 0x00 &&
247 bcmp(&in6->s6_addr[9], allzero, 7) == 0) {
248 return -1;
249 }
250
251 return 0;
252 }
253
254 /*
255 * Get interface identifier for the specified interface. If it is not
256 * available on ifp0, borrow interface identifier from other information
257 * sources.
258 */
259 static int
get_ifid(ifp0,altifp,in6)260 get_ifid(ifp0, altifp, in6)
261 struct ifnet *ifp0;
262 struct ifnet *altifp; /* secondary EUI64 source */
263 struct in6_addr *in6;
264 {
265 struct ifnet *ifp;
266
267 /* first, try to get it from the interface itself */
268 if (get_hw_ifid(ifp0, in6) == 0) {
269 nd6log((LOG_DEBUG, "%s: got interface identifier from itself\n",
270 ifp0->if_xname));
271 goto success;
272 }
273
274 /* try secondary EUI64 source. this basically is for ATM PVC */
275 if (altifp && get_hw_ifid(altifp, in6) == 0) {
276 nd6log((LOG_DEBUG, "%s: got interface identifier from %s\n",
277 ifp0->if_xname, altifp->if_xname));
278 goto success;
279 }
280
281 /* next, try to get it from some other hardware interface */
282 for (ifp = ifnet.tqh_first; ifp; ifp = ifp->if_list.tqe_next)
283 {
284 if (ifp == ifp0)
285 continue;
286 if (get_hw_ifid(ifp, in6) != 0)
287 continue;
288
289 /*
290 * to borrow ifid from other interface, ifid needs to be
291 * globally unique
292 */
293 if (IFID_UNIVERSAL(in6)) {
294 nd6log((LOG_DEBUG,
295 "%s: borrow interface identifier from %s\n",
296 ifp0->if_xname, ifp->if_xname));
297 goto success;
298 }
299 }
300
301 /* last resort: get from random number source */
302 if (get_rand_ifid(ifp, in6) == 0) {
303 nd6log((LOG_DEBUG,
304 "%s: interface identifier generated by random number\n",
305 ifp0->if_xname));
306 goto success;
307 }
308
309 printf("%s: failed to get interface identifier\n", ifp0->if_xname);
310 return -1;
311
312 success:
313 nd6log((LOG_INFO, "%s: ifid: %02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x\n",
314 ifp0->if_xname, in6->s6_addr[8], in6->s6_addr[9], in6->s6_addr[10],
315 in6->s6_addr[11], in6->s6_addr[12], in6->s6_addr[13],
316 in6->s6_addr[14], in6->s6_addr[15]));
317 return 0;
318 }
319
320 static int
in6_ifattach_linklocal(ifp,altifp)321 in6_ifattach_linklocal(ifp, altifp)
322 struct ifnet *ifp;
323 struct ifnet *altifp; /*secondary EUI64 source*/
324 {
325 struct in6_ifaddr *ia;
326 struct in6_aliasreq ifra;
327 struct nd_prefix pr0;
328 int i, error;
329
330 /*
331 * configure link-local address.
332 */
333 bzero(&ifra, sizeof(ifra));
334
335 /*
336 * in6_update_ifa() does not use ifra_name, but we accurately set it
337 * for safety.
338 */
339 strncpy(ifra.ifra_name, ifp->if_xname, sizeof(ifra.ifra_name));
340
341 ifra.ifra_addr.sin6_family = AF_INET6;
342 ifra.ifra_addr.sin6_len = sizeof(struct sockaddr_in6);
343 ifra.ifra_addr.sin6_addr.s6_addr16[0] = htons(0xfe80);
344 ifra.ifra_addr.sin6_addr.s6_addr16[1] = htons(ifp->if_index);
345 ifra.ifra_addr.sin6_addr.s6_addr32[1] = 0;
346 if ((ifp->if_flags & IFF_LOOPBACK) != 0) {
347 ifra.ifra_addr.sin6_addr.s6_addr32[2] = 0;
348 ifra.ifra_addr.sin6_addr.s6_addr32[3] = htonl(1);
349 } else {
350 if (get_ifid(ifp, altifp, &ifra.ifra_addr.sin6_addr) != 0) {
351 nd6log((LOG_ERR,
352 "%s: no ifid available\n", ifp->if_xname));
353 return (-1);
354 }
355 }
356
357 ifra.ifra_prefixmask.sin6_len = sizeof(struct sockaddr_in6);
358 ifra.ifra_prefixmask.sin6_family = AF_INET6;
359 ifra.ifra_prefixmask.sin6_addr = in6mask64;
360 #ifdef SCOPEDROUTING
361 /* take into account the sin6_scope_id field for routing */
362 ifra.ifra_prefixmask.sin6_scope_id = 0xffffffff;
363 #endif
364 /* link-local addresses should NEVER expire. */
365 ifra.ifra_lifetime.ia6t_vltime = ND6_INFINITE_LIFETIME;
366 ifra.ifra_lifetime.ia6t_pltime = ND6_INFINITE_LIFETIME;
367
368 /*
369 * Do not let in6_update_ifa() do DAD, since we need a random delay
370 * before sending an NS at the first time the interface becomes up.
371 * Instead, in6_if_up() will start DAD with a proper random delay.
372 */
373 ifra.ifra_flags |= IN6_IFF_NODAD;
374
375 /*
376 * Now call in6_update_ifa() to do a bunch of procedures to configure
377 * a link-local address. We can set NULL to the 3rd argument, because
378 * we know there's no other link-local address on the interface
379 * and therefore we are adding one (instead of updating one).
380 */
381 if ((error = in6_update_ifa(ifp, &ifra, NULL)) != 0) {
382 /*
383 * XXX: When the interface does not support IPv6, this call
384 * would fail in the SIOCSIFADDR ioctl. I believe the
385 * notification is rather confusing in this case, so just
386 * suppress it. (jinmei@kame.net 20010130)
387 */
388 if (error != EAFNOSUPPORT)
389 nd6log((LOG_NOTICE, "in6_ifattach_linklocal: failed to "
390 "configure a link-local address on %s "
391 "(errno=%d)\n",
392 ifp->if_xname, error));
393 return (-1);
394 }
395
396 /*
397 * Adjust ia6_flags so that in6_if_up will perform DAD.
398 * XXX: Some P2P interfaces seem not to send packets just after
399 * becoming up, so we skip p2p interfaces for safety.
400 */
401 ia = in6ifa_ifpforlinklocal(ifp, 0); /* ia must not be NULL */
402 #ifdef DIAGNOSTIC
403 if (!ia) {
404 panic("ia == NULL in in6_ifattach_linklocal");
405 /* NOTREACHED */
406 }
407 #endif
408 if (in6if_do_dad(ifp) && (ifp->if_flags & IFF_POINTOPOINT) == 0) {
409 ia->ia6_flags &= ~IN6_IFF_NODAD;
410 ia->ia6_flags |= IN6_IFF_TENTATIVE;
411 }
412
413 /*
414 * Make the link-local prefix (fe80::/64%link) as on-link.
415 * Since we'd like to manage prefixes separately from addresses,
416 * we make an ND6 prefix structure for the link-local prefix,
417 * and add it to the prefix list as a never-expire prefix.
418 * XXX: this change might affect some existing code base...
419 */
420 bzero(&pr0, sizeof(pr0));
421 pr0.ndpr_ifp = ifp;
422 /* this should be 64 at this moment. */
423 pr0.ndpr_plen = in6_mask2len(&ifra.ifra_prefixmask.sin6_addr, NULL);
424 pr0.ndpr_mask = ifra.ifra_prefixmask.sin6_addr;
425 pr0.ndpr_prefix = ifra.ifra_addr;
426 /* apply the mask for safety. (nd6_prelist_add will apply it again) */
427 for (i = 0; i < 4; i++) {
428 pr0.ndpr_prefix.sin6_addr.s6_addr32[i] &=
429 in6mask64.s6_addr32[i];
430 }
431 /*
432 * Initialize parameters. The link-local prefix must always be
433 * on-link, and its lifetimes never expire.
434 */
435 pr0.ndpr_raf_onlink = 1;
436 pr0.ndpr_raf_auto = 1; /* probably meaningless */
437 pr0.ndpr_vltime = ND6_INFINITE_LIFETIME;
438 pr0.ndpr_pltime = ND6_INFINITE_LIFETIME;
439 /*
440 * Since there is no other link-local addresses, nd6_prefix_lookup()
441 * probably returns NULL. However, we cannot always expect the result.
442 * For example, if we first remove the (only) existing link-local
443 * address, and then reconfigure another one, the prefix is still
444 * valid with referring to the old link-local address.
445 */
446 if (nd6_prefix_lookup(&pr0) == NULL) {
447 if ((error = nd6_prelist_add(&pr0, NULL, NULL)) != 0)
448 return (error);
449 }
450
451 return 0;
452 }
453
454 static int
in6_ifattach_loopback(ifp)455 in6_ifattach_loopback(ifp)
456 struct ifnet *ifp; /* must be IFT_LOOP */
457 {
458 struct in6_aliasreq ifra;
459 int error;
460
461 bzero(&ifra, sizeof(ifra));
462
463 /*
464 * in6_update_ifa() does not use ifra_name, but we accurately set it
465 * for safety.
466 */
467 strncpy(ifra.ifra_name, ifp->if_xname, sizeof(ifra.ifra_name));
468
469 ifra.ifra_prefixmask.sin6_len = sizeof(struct sockaddr_in6);
470 ifra.ifra_prefixmask.sin6_family = AF_INET6;
471 ifra.ifra_prefixmask.sin6_addr = in6mask128;
472
473 /*
474 * Always initialize ia_dstaddr (= broadcast address) to loopback
475 * address. Follows IPv4 practice - see in_ifinit().
476 */
477 ifra.ifra_dstaddr.sin6_len = sizeof(struct sockaddr_in6);
478 ifra.ifra_dstaddr.sin6_family = AF_INET6;
479 ifra.ifra_dstaddr.sin6_addr = in6addr_loopback;
480
481 ifra.ifra_addr.sin6_len = sizeof(struct sockaddr_in6);
482 ifra.ifra_addr.sin6_family = AF_INET6;
483 ifra.ifra_addr.sin6_addr = in6addr_loopback;
484
485 /* the loopback address should NEVER expire. */
486 ifra.ifra_lifetime.ia6t_vltime = ND6_INFINITE_LIFETIME;
487 ifra.ifra_lifetime.ia6t_pltime = ND6_INFINITE_LIFETIME;
488
489 /* we don't need to perform DAD on loopback interfaces. */
490 ifra.ifra_flags |= IN6_IFF_NODAD;
491
492 /*
493 * We are sure that this is a newly assigned address, so we can set
494 * NULL to the 3rd arg.
495 */
496 if ((error = in6_update_ifa(ifp, &ifra, NULL)) != 0) {
497 nd6log((LOG_ERR, "in6_ifattach_loopback: failed to configure "
498 "the loopback address on %s (errno=%d)\n",
499 ifp->if_xname, error));
500 return (-1);
501 }
502
503 return 0;
504 }
505
506 /*
507 * compute NI group address, based on the current hostname setting.
508 * see draft-ietf-ipngwg-icmp-name-lookup-* (04 and later).
509 *
510 * when ifp == NULL, the caller is responsible for filling scopeid.
511 */
512 int
in6_nigroup(ifp,name,namelen,sa6)513 in6_nigroup(ifp, name, namelen, sa6)
514 struct ifnet *ifp;
515 const char *name;
516 int namelen;
517 struct sockaddr_in6 *sa6;
518 {
519 const char *p;
520 u_int8_t *q;
521 MD5_CTX ctxt;
522 u_int8_t digest[16];
523 u_int8_t l;
524 u_int8_t n[64]; /* a single label must not exceed 63 chars */
525
526 if (!namelen || !name)
527 return -1;
528
529 p = name;
530 while (p && *p && *p != '.' && p - name < namelen)
531 p++;
532 if (p - name > sizeof(n) - 1)
533 return -1; /* label too long */
534 l = p - name;
535 strncpy((char *)n, name, l);
536 n[(int)l] = '\0';
537 for (q = n; *q; q++) {
538 if ('A' <= *q && *q <= 'Z')
539 *q = *q - 'A' + 'a';
540 }
541
542 /* generate 8 bytes of pseudo-random value. */
543 bzero(&ctxt, sizeof(ctxt));
544 MD5Init(&ctxt);
545 MD5Update(&ctxt, &l, sizeof(l));
546 MD5Update(&ctxt, n, l);
547 MD5Final(digest, &ctxt);
548
549 bzero(sa6, sizeof(*sa6));
550 sa6->sin6_family = AF_INET6;
551 sa6->sin6_len = sizeof(*sa6);
552 sa6->sin6_addr.s6_addr16[0] = htons(0xff02);
553 sa6->sin6_addr.s6_addr16[1] = htons(ifp->if_index);
554 sa6->sin6_addr.s6_addr8[11] = 2;
555 bcopy(digest, &sa6->sin6_addr.s6_addr32[3],
556 sizeof(sa6->sin6_addr.s6_addr32[3]));
557
558 return 0;
559 }
560
561 /*
562 * XXX multiple loopback interface needs more care. for instance,
563 * nodelocal address needs to be configured onto only one of them.
564 * XXX multiple link-local address case
565 */
566 void
in6_ifattach(ifp,altifp)567 in6_ifattach(ifp, altifp)
568 struct ifnet *ifp;
569 struct ifnet *altifp; /* secondary EUI64 source */
570 {
571 struct in6_ifaddr *ia;
572 struct in6_addr in6;
573
574 /* some of the interfaces are inherently not IPv6 capable */
575 switch (ifp->if_type) {
576 case IFT_BRIDGE:
577 case IFT_ENC:
578 case IFT_PFLOG:
579 case IFT_PFSYNC:
580 return;
581 }
582
583 /*
584 * if link mtu is too small, don't try to configure IPv6.
585 * remember there could be some link-layer that has special
586 * fragmentation logic.
587 */
588 if (ifp->if_mtu < IPV6_MMTU) {
589 nd6log((LOG_INFO, "in6_ifattach: "
590 "%s has too small MTU, IPv6 not enabled\n",
591 ifp->if_xname));
592 return;
593 }
594
595 /* create a multicast kludge storage (if we have not had one) */
596 in6_createmkludge(ifp);
597
598 /*
599 * quirks based on interface type
600 */
601 switch (ifp->if_type) {
602 case IFT_CARP:
603 return;
604 default:
605 break;
606 }
607
608 /*
609 * usually, we require multicast capability to the interface
610 */
611 if ((ifp->if_flags & IFF_MULTICAST) == 0) {
612 nd6log((LOG_INFO, "in6_ifattach: "
613 "%s is not multicast capable, IPv6 not enabled\n",
614 ifp->if_xname));
615 return;
616 }
617
618 /*
619 * assign loopback address for loopback interface.
620 * XXX multiple loopback interface case.
621 */
622 if ((ifp->if_flags & IFF_LOOPBACK) != 0) {
623 in6 = in6addr_loopback;
624 if (in6ifa_ifpwithaddr(ifp, &in6) == NULL) {
625 if (in6_ifattach_loopback(ifp) != 0)
626 return;
627 }
628 }
629
630 /*
631 * assign a link-local address, if there's none.
632 */
633 if (ip6_auto_linklocal) {
634 ia = in6ifa_ifpforlinklocal(ifp, 0);
635 if (ia == NULL) {
636 if (in6_ifattach_linklocal(ifp, altifp) == 0) {
637 /* linklocal address assigned */
638 } else {
639 /* failed to assign linklocal address. bark? */
640 }
641 }
642 }
643 }
644
645 /*
646 * NOTE: in6_ifdetach() does not support loopback if at this moment.
647 */
648 void
in6_ifdetach(ifp)649 in6_ifdetach(ifp)
650 struct ifnet *ifp;
651 {
652 struct in6_ifaddr *ia, *oia;
653 struct ifaddr *ifa, *next;
654 struct rtentry *rt;
655 short rtflags;
656 struct sockaddr_in6 sin6;
657 struct in6_multi_mship *imm;
658
659 /* remove ip6_mrouter stuff */
660 ip6_mrouter_detach(ifp);
661
662 /* remove neighbor management table */
663 nd6_purge(ifp);
664
665 /* nuke any of IPv6 addresses we have */
666 for (ifa = ifp->if_addrlist.tqh_first; ifa; ifa = next)
667 {
668 next = ifa->ifa_list.tqe_next;
669 if (ifa->ifa_addr->sa_family != AF_INET6)
670 continue;
671 in6_purgeaddr(ifa);
672 }
673
674 /* undo everything done by in6_ifattach(), just in case */
675 for (ifa = ifp->if_addrlist.tqh_first; ifa; ifa = next)
676 {
677 next = ifa->ifa_list.tqe_next;
678
679 if (ifa->ifa_addr->sa_family != AF_INET6
680 || !IN6_IS_ADDR_LINKLOCAL(&satosin6(&ifa->ifa_addr)->sin6_addr)) {
681 continue;
682 }
683
684 ia = (struct in6_ifaddr *)ifa;
685
686 /*
687 * leave from multicast groups we have joined for the interface
688 */
689 while ((imm = ia->ia6_memberships.lh_first) != NULL) {
690 LIST_REMOVE(imm, i6mm_chain);
691 in6_leavegroup(imm);
692 }
693
694 /* remove from the routing table */
695 if ((ia->ia_flags & IFA_ROUTE) &&
696 (rt = rtalloc1((struct sockaddr *)&ia->ia_addr, 0))) {
697 rtflags = rt->rt_flags;
698 rtfree(rt);
699 rtrequest(RTM_DELETE, (struct sockaddr *)&ia->ia_addr,
700 (struct sockaddr *)&ia->ia_addr,
701 (struct sockaddr *)&ia->ia_prefixmask,
702 rtflags, (struct rtentry **)0);
703 }
704
705 /* remove from the linked list */
706 TAILQ_REMOVE(&ifp->if_addrlist, (struct ifaddr *)ia, ifa_list);
707 IFAFREE(&ia->ia_ifa);
708
709 /* also remove from the IPv6 address chain(itojun&jinmei) */
710 oia = ia;
711 if (oia == (ia = in6_ifaddr))
712 in6_ifaddr = ia->ia_next;
713 else {
714 while (ia->ia_next && (ia->ia_next != oia))
715 ia = ia->ia_next;
716 if (ia->ia_next)
717 ia->ia_next = oia->ia_next;
718 else {
719 nd6log((LOG_ERR,
720 "%s: didn't unlink in6ifaddr from list\n",
721 ifp->if_xname));
722 }
723 }
724
725 IFAFREE(&oia->ia_ifa);
726 }
727
728 /* cleanup multicast address kludge table, if there is any */
729 in6_purgemkludge(ifp);
730
731 /*
732 * remove neighbor management table. we call it twice just to make
733 * sure we nuke everything. maybe we need just one call.
734 * XXX: since the first call did not release addresses, some prefixes
735 * might remain. We should call nd6_purge() again to release the
736 * prefixes after removing all addresses above.
737 * (Or can we just delay calling nd6_purge until at this point?)
738 */
739 nd6_purge(ifp);
740
741 /* remove route to link-local allnodes multicast (ff02::1) */
742 bzero(&sin6, sizeof(sin6));
743 sin6.sin6_len = sizeof(struct sockaddr_in6);
744 sin6.sin6_family = AF_INET6;
745 sin6.sin6_addr = in6addr_linklocal_allnodes;
746 sin6.sin6_addr.s6_addr16[1] = htons(ifp->if_index);
747 rt = rtalloc1((struct sockaddr *)&sin6, 0);
748 if (rt && rt->rt_ifp == ifp) {
749 rtrequest(RTM_DELETE, (struct sockaddr *)rt_key(rt),
750 rt->rt_gateway, rt_mask(rt), rt->rt_flags, 0);
751 rtfree(rt);
752 }
753 }
754