xref: /dragonfly/sys/netinet6/in6_ifattach.c (revision 6a3cbbc2)
1 /*	$FreeBSD: src/sys/netinet6/in6_ifattach.c,v 1.2.2.6 2002/04/28 05:40:26 suz Exp $	*/
2 /*	$KAME: in6_ifattach.c,v 1.118 2001/05/24 07:44:00 itojun Exp $	*/
3 
4 /*
5  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. Neither the name of the project nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 #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 #include <sys/md5.h>
41 #include <sys/thread2.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 #include <net/netisr2.h>
48 #include <net/netmsg2.h>
49 
50 #include <netinet/in.h>
51 #include <netinet/in_var.h>
52 #include <netinet/if_ether.h>
53 #include <netinet/in_pcb.h>
54 #include <netinet/udp_var.h>
55 
56 #include <netinet/ip6.h>
57 #include <netinet6/ip6_var.h>
58 #include <netinet6/in6_var.h>
59 #include <netinet6/in6_pcb.h>
60 #include <netinet6/in6_ifattach.h>
61 #include <netinet6/nd6.h>
62 #include <netinet6/scope6_var.h>
63 
64 #include <net/net_osdep.h>
65 
66 unsigned long in6_maxmtu = 0;
67 
68 #ifdef IP6_AUTO_LINKLOCAL
69 int ip6_auto_linklocal = IP6_AUTO_LINKLOCAL;
70 #else
71 int ip6_auto_linklocal = 1;	/* enable by default */
72 #endif
73 
74 static struct callout in6_tmpaddrtimer_ch;
75 static struct netmsg_base in6_tmpaddrtimer_netmsg;
76 
77 extern struct inpcbinfo ripcbinfo;
78 
79 static int get_rand_ifid (struct in6_addr *);
80 static int generate_tmp_ifid (u_int8_t *, const u_int8_t *, u_int8_t *);
81 static int get_hw_ifid (struct ifnet *, struct in6_addr *);
82 static int get_ifid (struct ifnet *, struct ifnet *, struct in6_addr *);
83 static int in6_ifattach_linklocal (struct ifnet *, struct ifnet *);
84 static int in6_ifattach_loopback (struct ifnet *);
85 
86 #define EUI64_GBIT	0x01
87 #define EUI64_UBIT	0x02
88 #define EUI64_TO_IFID(in6)	do {(in6)->s6_addr[8] ^= EUI64_UBIT; } while (0)
89 #define EUI64_GROUP(in6)	((in6)->s6_addr[8] & EUI64_GBIT)
90 #define EUI64_INDIVIDUAL(in6)	(!EUI64_GROUP(in6))
91 #define EUI64_LOCAL(in6)	((in6)->s6_addr[8] & EUI64_UBIT)
92 #define EUI64_UNIVERSAL(in6)	(!EUI64_LOCAL(in6))
93 
94 #define IFID_LOCAL(in6)		(!EUI64_LOCAL(in6))
95 #define IFID_UNIVERSAL(in6)	(!EUI64_UNIVERSAL(in6))
96 
97 /*
98  * Generate a last-resort interface identifier, when the machine has no
99  * IEEE802/EUI64 address sources.
100  * The goal here is to get an interface identifier that is
101  * (1) random enough and (2) does not change across reboot.
102  * We currently use MD5(hostname) for it.
103  */
104 static int
105 get_rand_ifid(struct in6_addr *in6)	/* upper 64bits are preserved */
106 {
107 	MD5_CTX ctxt;
108 	u_int8_t digest[16];
109 	int hostnamelen	= strlen(hostname);
110 
111 #if 0
112 	/* we need at least several letters as seed for ifid */
113 	if (hostnamelen < 3)
114 		return -1;
115 #endif
116 
117 	/* generate 8 bytes of pseudo-random value. */
118 	bzero(&ctxt, sizeof(ctxt));
119 	MD5Init(&ctxt);
120 	MD5Update(&ctxt, hostname, hostnamelen);
121 	MD5Final(digest, &ctxt);
122 
123 	/* assumes sizeof(digest) > sizeof(ifid) */
124 	bcopy(digest, &in6->s6_addr[8], 8);
125 
126 	/* make sure to set "u" bit to local, and "g" bit to individual. */
127 	in6->s6_addr[8] &= ~EUI64_GBIT;	/* g bit to "individual" */
128 	in6->s6_addr[8] |= EUI64_UBIT;	/* u bit to "local" */
129 
130 	/* convert EUI64 into IPv6 interface identifier */
131 	EUI64_TO_IFID(in6);
132 
133 	return 0;
134 }
135 
136 static int
137 generate_tmp_ifid(u_int8_t *seed0, const u_int8_t *seed1, u_int8_t *ret)
138 {
139 	MD5_CTX ctxt;
140 	u_int8_t seed[16], digest[16], nullbuf[8];
141 	u_int32_t val32;
142 	struct timeval tv;
143 
144 	/* If there's no hisotry, start with a random seed. */
145 	bzero(nullbuf, sizeof(nullbuf));
146 	if (bcmp(nullbuf, seed0, sizeof(nullbuf)) == 0) {
147 		int i;
148 
149 		for (i = 0; i < 2; i++) {
150 			microtime(&tv);
151 			val32 = krandom() ^ tv.tv_usec;
152 			bcopy(&val32, seed + sizeof(val32) * i, sizeof(val32));
153 		}
154 	} else {
155 		bcopy(seed0, seed, 8);
156 	}
157 
158 	/* copy the right-most 64-bits of the given address */
159 	/* XXX assumption on the size of IFID */
160 	bcopy(seed1, &seed[8], 8);
161 
162 	if (0) {		/* for debugging purposes only */
163 		int i;
164 
165 		kprintf("generate_tmp_ifid: new randomized ID from: ");
166 		for (i = 0; i < 16; i++)
167 			kprintf("%02x", seed[i]);
168 		kprintf(" ");
169 	}
170 
171 	/* generate 16 bytes of pseudo-random value. */
172 	bzero(&ctxt, sizeof(ctxt));
173 	MD5Init(&ctxt);
174 	MD5Update(&ctxt, seed, sizeof(seed));
175 	MD5Final(digest, &ctxt);
176 
177 	/*
178 	 * RFC 3041 3.2.1. (3)
179 	 * Take the left-most 64-bits of the MD5 digest and set bit 6 (the
180 	 * left-most bit is numbered 0) to zero.
181 	 */
182 	bcopy(digest, ret, 8);
183 	ret[0] &= ~EUI64_UBIT;
184 
185 	/*
186 	 * XXX: we'd like to ensure that the generated value is not zero
187 	 * for simplicity.  If the caclculated digest happens to be zero,
188 	 * use a random non-zero value as the last resort.
189 	 */
190 	if (bcmp(nullbuf, ret, sizeof(nullbuf)) == 0) {
191 		log(LOG_INFO,
192 		    "generate_tmp_ifid: computed MD5 value is zero.\n");
193 
194 		microtime(&tv);
195 		val32 = krandom() ^ tv.tv_usec;
196 		val32 = 1 + (val32 % (0xffffffff - 1));
197 	}
198 
199 	/*
200 	 * RFC 3041 3.2.1. (4)
201 	 * Take the rightmost 64-bits of the MD5 digest and save them in
202 	 * stable storage as the history value to be used in the next
203 	 * iteration of the algorithm.
204 	 */
205 	bcopy(&digest[8], seed0, 8);
206 
207 	if (0) {		/* for debugging purposes only */
208 		int i;
209 
210 		kprintf("to: ");
211 		for (i = 0; i < 16; i++)
212 			kprintf("%02x", digest[i]);
213 		kprintf("\n");
214 	}
215 
216 	return 0;
217 }
218 
219 /*
220  * Get interface identifier for the specified interface.
221  * XXX assumes single sockaddr_dl (AF_LINK address) per an interface
222  */
223 static int
224 get_hw_ifid(struct ifnet *ifp,
225 	    struct in6_addr *in6)	/* upper 64bits are preserved */
226 {
227 	struct ifaddr_container *ifac;
228 	struct sockaddr_dl *sdl;
229 	u_int8_t *addr;
230 	size_t addrlen;
231 	static u_int8_t allzero[8] = { 0, 0, 0, 0, 0, 0, 0, 0 };
232 	static u_int8_t allone[8] =
233 		{ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
234 
235 	TAILQ_FOREACH(ifac, &ifp->if_addrheads[mycpuid], ifa_link) {
236 		struct ifaddr *ifa = ifac->ifa;
237 
238 		if (ifa->ifa_addr->sa_family != AF_LINK)
239 			continue;
240 		sdl = (struct sockaddr_dl *)ifa->ifa_addr;
241 		if (sdl == NULL)
242 			continue;
243 		if (sdl->sdl_alen == 0)
244 			continue;
245 
246 		goto found;
247 	}
248 
249 	return -1;
250 
251 found:
252 	addr = LLADDR(sdl);
253 	addrlen = sdl->sdl_alen;
254 
255 	/* get EUI64 */
256 	switch (ifp->if_type) {
257 	case IFT_ETHER:
258 	case IFT_ATM:
259 	case IFT_IEEE1394:
260 #ifdef IFT_IEEE80211
261 	case IFT_IEEE80211:
262 #endif
263 		/* IEEE802/EUI64 cases - what others? */
264 		/* IEEE1394 uses 16byte length address starting with EUI64 */
265 		if (addrlen > 8)
266 			addrlen = 8;
267 
268 		/* look at IEEE802/EUI64 only */
269 		if (addrlen != 8 && addrlen != 6)
270 			return -1;
271 
272 		/*
273 		 * check for invalid MAC address - on bsdi, we see it a lot
274 		 * since wildboar configures all-zero MAC on pccard before
275 		 * card insertion.
276 		 */
277 		if (bcmp(addr, allzero, addrlen) == 0)
278 			return -1;
279 		if (bcmp(addr, allone, addrlen) == 0)
280 			return -1;
281 
282 		/* make EUI64 address */
283 		if (addrlen == 8)
284 			bcopy(addr, &in6->s6_addr[8], 8);
285 		else if (addrlen == 6) {
286 			in6->s6_addr[8] = addr[0];
287 			in6->s6_addr[9] = addr[1];
288 			in6->s6_addr[10] = addr[2];
289 			in6->s6_addr[11] = 0xff;
290 			in6->s6_addr[12] = 0xfe;
291 			in6->s6_addr[13] = addr[3];
292 			in6->s6_addr[14] = addr[4];
293 			in6->s6_addr[15] = addr[5];
294 		}
295 		break;
296 	case IFT_GIF:
297 #ifdef IFT_STF
298 	case IFT_STF:
299 #endif
300 		/*
301 		 * RFC2893 says: "SHOULD use IPv4 address as ifid source".
302 		 * however, IPv4 address is not very suitable as unique
303 		 * identifier source (can be renumbered).
304 		 * we don't do this.
305 		 */
306 		return -1;
307 
308 	default:
309 		return -1;
310 	}
311 
312 	/* sanity check: g bit must not indicate "group" */
313 	if (EUI64_GROUP(in6))
314 		return -1;
315 
316 	/* convert EUI64 into IPv6 interface identifier */
317 	EUI64_TO_IFID(in6);
318 
319 	/*
320 	 * sanity check: ifid must not be all zero, avoid conflict with
321 	 * subnet router anycast
322 	 */
323 	if ((in6->s6_addr[8] & ~(EUI64_GBIT | EUI64_UBIT)) == 0x00 &&
324 	    bcmp(&in6->s6_addr[9], allzero, 7) == 0) {
325 		return -1;
326 	}
327 
328 	return 0;
329 }
330 
331 /*
332  * Get interface identifier for the specified interface.  If it is not
333  * available on ifp0, borrow interface identifier from other information
334  * sources.
335  */
336 static int
337 get_ifid(struct ifnet *ifp0,
338 	 struct ifnet *altifp,	/* secondary EUI64 source */
339 	 struct in6_addr *in6)
340 {
341 	const struct ifnet_array *arr;
342 	int i;
343 
344 	/* first, try to get it from the interface itself */
345 	if (get_hw_ifid(ifp0, in6) == 0) {
346 		nd6log((LOG_DEBUG, "%s: got interface identifier from itself\n",
347 		    if_name(ifp0)));
348 		goto success;
349 	}
350 
351 	/* try secondary EUI64 source. this basically is for ATM PVC */
352 	if (altifp && get_hw_ifid(altifp, in6) == 0) {
353 		nd6log((LOG_DEBUG, "%s: got interface identifier from %s\n",
354 		    if_name(ifp0), if_name(altifp)));
355 		goto success;
356 	}
357 
358 	/* next, try to get it from some other hardware interface */
359 	arr = ifnet_array_get();
360 	for (i = 0; i < arr->ifnet_count; ++i) {
361 		struct ifnet *ifp = arr->ifnet_arr[i];
362 
363 		if (ifp == ifp0)
364 			continue;
365 		if (get_hw_ifid(ifp, in6) != 0)
366 			continue;
367 
368 		/*
369 		 * to borrow ifid from other interface, ifid needs to be
370 		 * globally unique
371 		 */
372 		if (IFID_UNIVERSAL(in6)) {
373 			nd6log((LOG_DEBUG,
374 			    "%s: borrow interface identifier from %s\n",
375 			    if_name(ifp0), if_name(ifp)));
376 			goto success;
377 		}
378 	}
379 
380 	/* last resort: get from random number source */
381 	if (get_rand_ifid(in6) == 0) {
382 		nd6log((LOG_DEBUG,
383 		    "%s: interface identifier generated by random number\n",
384 		    if_name(ifp0)));
385 		goto success;
386 	}
387 
388 	kprintf("%s: failed to get interface identifier\n", if_name(ifp0));
389 	return -1;
390 
391 success:
392 	nd6log((LOG_INFO, "%s: ifid: "
393 		"%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x\n",
394 		if_name(ifp0),
395 		in6->s6_addr[8], in6->s6_addr[9],
396 		in6->s6_addr[10], in6->s6_addr[11],
397 		in6->s6_addr[12], in6->s6_addr[13],
398 		in6->s6_addr[14], in6->s6_addr[15]));
399 	return 0;
400 }
401 
402 static int
403 in6_ifattach_linklocal(struct ifnet *ifp,
404 		       struct ifnet *altifp)	/* secondary EUI64 source */
405 {
406 	struct in6_ifaddr *ia;
407 	struct in6_aliasreq ifra;
408 	struct nd_prefix pr0;
409 	int i, error;
410 
411 	/*
412 	 * configure link-local address.
413 	 */
414 	bzero(&ifra, sizeof(ifra));
415 
416 	/*
417 	 * in6_update_ifa() does not use ifra_name, but we accurately set it
418 	 * for safety.
419 	 */
420 	strncpy(ifra.ifra_name, if_name(ifp), sizeof(ifra.ifra_name));
421 
422 	ifra.ifra_addr.sin6_family = AF_INET6;
423 	ifra.ifra_addr.sin6_len = sizeof(struct sockaddr_in6);
424 	ifra.ifra_addr.sin6_addr.s6_addr16[0] = htons(0xfe80);
425 	ifra.ifra_addr.sin6_addr.s6_addr16[1] = htons(ifp->if_index); /* XXX */
426 	ifra.ifra_addr.sin6_addr.s6_addr32[1] = 0;
427 	if (ifp->if_flags & IFF_LOOPBACK) {
428 		ifra.ifra_addr.sin6_addr.s6_addr32[2] = 0;
429 		ifra.ifra_addr.sin6_addr.s6_addr32[3] = htonl(1);
430 	} else {
431 		if (get_ifid(ifp, altifp, &ifra.ifra_addr.sin6_addr) != 0) {
432 			nd6log((LOG_ERR,
433 			    "%s: no ifid available\n", if_name(ifp)));
434 			return -1;
435 		}
436 	}
437 
438 	ifra.ifra_prefixmask.sin6_len = sizeof(struct sockaddr_in6);
439 	ifra.ifra_prefixmask.sin6_family = AF_INET6;
440 	ifra.ifra_prefixmask.sin6_addr = in6mask64;
441 
442 	/* link-local addresses should NEVER expire. */
443 	ifra.ifra_lifetime.ia6t_vltime = ND6_INFINITE_LIFETIME;
444 	ifra.ifra_lifetime.ia6t_pltime = ND6_INFINITE_LIFETIME;
445 
446 	/*
447 	 * Do not let in6_update_ifa() do DAD, since we need a random delay
448 	 * before sending an NS at the first time the interface becomes up.
449 	 * Instead, in6_if_up() will start DAD with a proper random delay.
450 	 */
451 	ifra.ifra_flags |= IN6_IFF_NODAD;
452 
453 	/*
454 	 * Now call in6_update_ifa() to do a bunch of procedures to configure
455 	 * a link-local address. We can set NULL to the 3rd argument, because
456 	 * we know there's no other link-local address on the interface
457 	 * and therefore we are adding one (instead of updating one).
458 	 */
459 	if ((error = in6_update_ifa(ifp, &ifra, NULL)) != 0) {
460 		/*
461 		 * XXX: When the interface does not support IPv6, this call
462 		 * would fail in the SIOCSIFADDR ioctl.  I believe the
463 		 * notification is rather confusing in this case, so just
464 		 * suppress it.  (jinmei@kame.net 20010130)
465 		 */
466 		if (error != EAFNOSUPPORT)
467 			log(LOG_NOTICE, "in6_ifattach_linklocal: failed to "
468 			    "configure a link-local address on %s "
469 			    "(errno=%d)\n",
470 			    if_name(ifp), error);
471 		return (-1);
472 	}
473 
474 	/*
475 	 * Adjust ia6_flags so that in6_if_up will perform DAD.
476 	 * XXX: Some P2P interfaces seem not to send packets just after
477 	 * becoming up, so we skip p2p interfaces for safety.
478 	 */
479 	ia = in6ifa_ifpforlinklocal(ifp, 0); /* ia must not be NULL */
480 #ifdef DIAGNOSTIC
481 	if (!ia) {
482 		panic("ia == NULL in in6_ifattach_linklocal");
483 		/* NOTREACHED */
484 	}
485 #endif
486 	if (in6if_do_dad(ifp) && !(ifp->if_flags & IFF_POINTOPOINT)) {
487 		ia->ia6_flags &= ~IN6_IFF_NODAD;
488 		ia->ia6_flags |= IN6_IFF_TENTATIVE;
489 	}
490 
491 	/*
492 	 * Make the link-local prefix (fe80::%link/64) as on-link.
493 	 * Since we'd like to manage prefixes separately from addresses,
494 	 * we make an ND6 prefix structure for the link-local prefix,
495 	 * and add it to the prefix list as a never-expire prefix.
496 	 * XXX: this change might affect some existing code base...
497 	 */
498 	bzero(&pr0, sizeof(pr0));
499 	pr0.ndpr_ifp = ifp;
500 	/* this should be 64 at this moment. */
501 	pr0.ndpr_plen = in6_mask2len(&ifra.ifra_prefixmask.sin6_addr, NULL);
502 	pr0.ndpr_mask = ifra.ifra_prefixmask.sin6_addr;
503 	pr0.ndpr_prefix = ifra.ifra_addr;
504 	/* apply the mask for safety. (nd6_prelist_add will apply it again) */
505 	for (i = 0; i < 4; i++) {
506 		pr0.ndpr_prefix.sin6_addr.s6_addr32[i] &=
507 		    in6mask64.s6_addr32[i];
508 	}
509 	/*
510 	 * Initialize parameters.  The link-local prefix must always be
511 	 * on-link, and its lifetimes never expire.
512 	 */
513 	pr0.ndpr_raf_onlink = 1;
514 	pr0.ndpr_raf_auto = 1;	/* probably meaningless */
515 	pr0.ndpr_vltime = ND6_INFINITE_LIFETIME;
516 	pr0.ndpr_pltime = ND6_INFINITE_LIFETIME;
517 	/*
518 	 * Since there is no other link-local addresses, nd6_prefix_lookup()
519 	 * probably returns NULL.  However, we cannot always expect the result.
520 	 * For example, if we first remove the (only) existing link-local
521 	 * address, and then reconfigure another one, the prefix is still
522 	 * valid with referring to the old link-local address.
523 	 */
524 	if (nd6_prefix_lookup(&pr0) == NULL) {
525 		if ((error = nd6_prelist_add(&pr0, NULL, NULL)) != 0)
526 			return (error);
527 	}
528 
529 	return 0;
530 }
531 
532 static int
533 in6_ifattach_loopback(struct ifnet *ifp)	/* must be IFT_LOOP */
534 {
535 	struct in6_aliasreq ifra;
536 	int error;
537 
538 	bzero(&ifra, sizeof(ifra));
539 
540 	/*
541 	 * in6_update_ifa() does not use ifra_name, but we accurately set it
542 	 * for safety.
543 	 */
544 	strncpy(ifra.ifra_name, if_name(ifp), sizeof(ifra.ifra_name));
545 
546 	ifra.ifra_prefixmask.sin6_len = sizeof(struct sockaddr_in6);
547 	ifra.ifra_prefixmask.sin6_family = AF_INET6;
548 	ifra.ifra_prefixmask.sin6_addr = in6mask128;
549 
550 	/*
551 	 * Always initialize ia_dstaddr (= broadcast address) to loopback
552 	 * address.  Follows IPv4 practice - see in_ifinit().
553 	 */
554 	ifra.ifra_dstaddr.sin6_len = sizeof(struct sockaddr_in6);
555 	ifra.ifra_dstaddr.sin6_family = AF_INET6;
556 	ifra.ifra_dstaddr.sin6_addr = kin6addr_loopback;
557 
558 	ifra.ifra_addr.sin6_len = sizeof(struct sockaddr_in6);
559 	ifra.ifra_addr.sin6_family = AF_INET6;
560 	ifra.ifra_addr.sin6_addr = kin6addr_loopback;
561 
562 	/* the loopback  address should NEVER expire. */
563 	ifra.ifra_lifetime.ia6t_vltime = ND6_INFINITE_LIFETIME;
564 	ifra.ifra_lifetime.ia6t_pltime = ND6_INFINITE_LIFETIME;
565 
566 	/* we don't need to perform DAD on loopback interfaces. */
567 	ifra.ifra_flags |= IN6_IFF_NODAD;
568 
569 	/* skip registration to the prefix list. XXX should be temporary. */
570 	ifra.ifra_flags |= IN6_IFF_NOPFX;
571 
572 	/*
573 	 * We are sure that this is a newly assigned address, so we can set
574 	 * NULL to the 3rd arg.
575 	 */
576 	if ((error = in6_update_ifa(ifp, &ifra, NULL)) != 0) {
577 		log(LOG_ERR, "in6_ifattach_loopback: failed to configure "
578 		    "the loopback address on %s (errno=%d)\n",
579 		    if_name(ifp), error);
580 		return (-1);
581 	}
582 
583 	return 0;
584 }
585 
586 /*
587  * compute NI group address, based on the current hostname setting.
588  * see draft-ietf-ipngwg-icmp-name-lookup-* (04 and later).
589  *
590  * when ifp == NULL, the caller is responsible for filling scopeid.
591  */
592 int
593 in6_nigroup(struct ifnet *ifp, const char *name, int namelen,
594 	    struct in6_addr *in6)
595 {
596 	const char *p;
597 	u_char *q;
598 	MD5_CTX ctxt;
599 	u_int8_t digest[16];
600 	char l;
601 	char n[64];	/* a single label must not exceed 63 chars */
602 
603 	if (!namelen || !name)
604 		return -1;
605 
606 	p = name;
607 	while (p && *p && *p != '.' && p - name < namelen)
608 		p++;
609 	if (p - name > sizeof(n) - 1)
610 		return -1;	/* label too long */
611 	l = p - name;
612 	strncpy(n, name, l);
613 	n[(int)l] = '\0';
614 	for (q = n; *q; q++) {
615 		if ('A' <= *q && *q <= 'Z')
616 			*q = *q - 'A' + 'a';
617 	}
618 
619 	/* generate 8 bytes of pseudo-random value. */
620 	bzero(&ctxt, sizeof(ctxt));
621 	MD5Init(&ctxt);
622 	MD5Update(&ctxt, &l, sizeof(l));
623 	MD5Update(&ctxt, n, l);
624 	MD5Final(digest, &ctxt);
625 
626 	bzero(in6, sizeof(*in6));
627 	in6->s6_addr16[0] = htons(0xff02);
628 	if (ifp)
629 		in6->s6_addr16[1] = htons(ifp->if_index);
630 	in6->s6_addr8[11] = 2;
631 	bcopy(digest, &in6->s6_addr32[3], sizeof(in6->s6_addr32[3]));
632 
633 	return 0;
634 }
635 
636 struct netmsg_nigroup {
637 	struct netmsg_base	nmsg;
638 	const char		*name;
639 	int			namelen;
640 };
641 
642 static void
643 in6_nigroup_attach_dispatch(netmsg_t msg)
644 {
645 	struct netmsg_nigroup *nmsg = (struct netmsg_nigroup *)msg;
646 	struct sockaddr_in6 mltaddr;
647 	struct in6_multi *in6m;
648 	const struct ifnet_array *arr;
649 	int error, i;
650 
651 	bzero(&mltaddr, sizeof(mltaddr));
652 	mltaddr.sin6_family = AF_INET6;
653 	mltaddr.sin6_len = sizeof(struct sockaddr_in6);
654 	if (in6_nigroup(NULL, nmsg->name, nmsg->namelen,
655 	    &mltaddr.sin6_addr) != 0)
656 		goto done;
657 
658 	arr = ifnet_array_get();
659 	for (i = 0; i < arr->ifnet_count; ++i) {
660 		struct ifnet *ifp = arr->ifnet_arr[i];
661 
662 		mltaddr.sin6_addr.s6_addr16[1] = htons(ifp->if_index);
663 		in6m = IN6_LOOKUP_MULTI(&mltaddr.sin6_addr, ifp);
664 		if (!in6m) {
665 			if (!in6_addmulti(&mltaddr.sin6_addr, ifp, &error)) {
666 				nd6log((LOG_ERR, "%s: failed to join %s "
667 				    "(errno=%d)\n", if_name(ifp),
668 				    ip6_sprintf(&mltaddr.sin6_addr),
669 				    error));
670 			}
671 		}
672 	}
673 done:
674 	lwkt_replymsg(&nmsg->nmsg.lmsg, 0);
675 }
676 
677 void
678 in6_nigroup_attach(const char *name, int namelen)
679 {
680 	struct netmsg_nigroup nmsg;
681 
682 	netmsg_init(&nmsg.nmsg, NULL, &curthread->td_msgport, 0,
683 	    in6_nigroup_attach_dispatch);
684 	nmsg.name = name;
685 	nmsg.namelen = namelen;
686 	lwkt_domsg(netisr_cpuport(0), &nmsg.nmsg.lmsg, 0);
687 }
688 
689 static void
690 in6_nigroup_detach_dispatch(netmsg_t msg)
691 {
692 	struct netmsg_nigroup *nmsg = (struct netmsg_nigroup *)msg;
693 	struct sockaddr_in6 mltaddr;
694 	struct in6_multi *in6m;
695 	const struct ifnet_array *arr;
696 	int i;
697 
698 	bzero(&mltaddr, sizeof(mltaddr));
699 	mltaddr.sin6_family = AF_INET6;
700 	mltaddr.sin6_len = sizeof(struct sockaddr_in6);
701 	if (in6_nigroup(NULL, nmsg->name, nmsg->namelen,
702 	    &mltaddr.sin6_addr) != 0)
703 		goto done;
704 
705 	arr = ifnet_array_get();
706 	for (i = 0; i < arr->ifnet_count; ++i) {
707 		struct ifnet *ifp = arr->ifnet_arr[i];
708 
709 		mltaddr.sin6_addr.s6_addr16[1] = htons(ifp->if_index);
710 		in6m = IN6_LOOKUP_MULTI(&mltaddr.sin6_addr, ifp);
711 		if (in6m)
712 			in6_delmulti(in6m);
713 	}
714 done:
715 	lwkt_replymsg(&nmsg->nmsg.lmsg, 0);
716 }
717 
718 void
719 in6_nigroup_detach(const char *name, int namelen)
720 {
721 	struct netmsg_nigroup nmsg;
722 
723 	netmsg_init(&nmsg.nmsg, NULL, &curthread->td_msgport, 0,
724 	    in6_nigroup_detach_dispatch);
725 	nmsg.name = name;
726 	nmsg.namelen = namelen;
727 	lwkt_domsg(netisr_cpuport(0), &nmsg.nmsg.lmsg, 0);
728 }
729 
730 /*
731  * XXX multiple loopback interface needs more care.  for instance,
732  * nodelocal address needs to be configured onto only one of them.
733  * XXX multiple link-local address case
734  */
735 void
736 in6_ifattach(struct ifnet *ifp,
737 	     struct ifnet *altifp)	/* secondary EUI64 source */
738 {
739 	struct in6_ifaddr *ia;
740 	struct in6_addr in6;
741 
742 	/* some of the interfaces are inherently not IPv6 capable */
743 	switch (ifp->if_type) {
744 #ifdef IFT_BRIDGE	/* OpenBSD 2.8, NetBSD 1.6 */
745 	case IFT_BRIDGE:
746 		return;
747 #endif
748 	case IFT_PFLOG:
749 	case IFT_PFSYNC:
750 	case IFT_CARP:
751 		return;
752 	}
753 
754 	/*
755 	 * quirks based on interface type
756 	 */
757 	switch (ifp->if_type) {
758 #ifdef IFT_STF
759 	case IFT_STF:
760 		/*
761 		 * 6to4 interface is a very special kind of beast.
762 		 * no multicast, no linklocal.  RFC2529 specifies how to make
763 		 * linklocals for 6to4 interface, but there's no use and
764 		 * it is rather harmful to have one.
765 		 */
766 		goto statinit;
767 #endif
768 	default:
769 		break;
770 	}
771 
772 	/*
773 	 * usually, we require multicast capability to the interface
774 	 */
775 	if (!(ifp->if_flags & IFF_MULTICAST)) {
776 		log(LOG_INFO, "in6_ifattach: "
777 		    "%s is not multicast capable, IPv6 not enabled\n",
778 		    if_name(ifp));
779 		return;
780 	}
781 
782 	/*
783 	 * assign loopback address for loopback interface.
784 	 * XXX multiple loopback interface case.
785 	 */
786 	if (ifp->if_flags & IFF_LOOPBACK) {
787 		in6 = kin6addr_loopback;
788 		if (in6ifa_ifpwithaddr(ifp, &in6) == NULL) {
789 			if (in6_ifattach_loopback(ifp) != 0)
790 				return;
791 		}
792 	}
793 
794 	/*
795 	 * assign a link-local address, if there's none.
796 	 */
797 	if (ip6_auto_linklocal) {
798 		ia = in6ifa_ifpforlinklocal(ifp, 0);
799 		if (ia == NULL) {
800 			if (in6_ifattach_linklocal(ifp, altifp) == 0) {
801 				/* linklocal address assigned */
802 			} else {
803 				/* failed to assign linklocal address. bark? */
804 			}
805 		}
806 	}
807 
808 #ifdef IFT_STF			/* XXX */
809 statinit:
810 #endif
811 
812 	/* update dynamically. */
813 	if (in6_maxmtu < ifp->if_mtu)
814 		in6_maxmtu = ifp->if_mtu;
815 }
816 
817 /*
818  * NOTE: in6_ifdetach() does not support loopback if at this moment.
819  */
820 static void
821 in6_ifdetach_dispatch(netmsg_t nmsg)
822 {
823 	struct lwkt_msg *lmsg = &nmsg->lmsg;
824 	struct ifnet *ifp = lmsg->u.ms_resultp;
825 	struct ifaddr_container *ifac, *next;
826 	struct rtentry *rt;
827 	struct sockaddr_in6 sin6;
828 	struct in6_multi *in6m, *in6m_next;
829 
830 	ASSERT_NETISR0;
831 
832 	/* remove neighbor management table */
833 	nd6_purge(ifp);
834 
835 	/* nuke any of IPv6 addresses we have */
836 	TAILQ_FOREACH_MUTABLE(ifac, &ifp->if_addrheads[mycpuid], ifa_link,
837 	    next) {
838 		struct ifaddr *ifa = ifac->ifa;
839 
840 		if (ifa->ifa_addr->sa_family != AF_INET6)
841 			continue;
842 		in6_purgeaddr(ifa);
843 	}
844 
845 	/*
846 	 * XXX
847 	 * These were code trying to nuke inet6 addresses again, but all
848 	 * inet6 addresses must have been deleted above; use assertion.
849 	 */
850 	TAILQ_FOREACH(ifac, &ifp->if_addrheads[mycpuid], ifa_link) {
851 		KASSERT(ifac->ifa->ifa_addr->sa_family != AF_INET6,
852 		    ("still has inet6 addr"));
853 	}
854 
855 	/* leave from all multicast groups joined */
856 	in6_pcbpurgeif0(&ripcbinfo, ifp);
857 	in6_pcbpurgeif0(&udbinfo[0], ifp);
858 	for (in6m = LIST_FIRST(&in6_multihead); in6m; in6m = in6m_next) {
859 		in6m_next = LIST_NEXT(in6m, in6m_entry);
860 		if (in6m->in6m_ifp != ifp)
861 			continue;
862 		in6_delmulti(in6m);
863 		in6m = NULL;
864 	}
865 
866 	/*
867 	 * remove neighbor management table.  we call it twice just to make
868 	 * sure we nuke everything.  maybe we need just one call.
869 	 * XXX: since the first call did not release addresses, some prefixes
870 	 * might remain.  We should call nd6_purge() again to release the
871 	 * prefixes after removing all addresses above.
872 	 * (Or can we just delay calling nd6_purge until at this point?)
873 	 */
874 	nd6_purge(ifp);
875 
876 	/* remove route to link-local allnodes multicast (ff02::1) */
877 	bzero(&sin6, sizeof(sin6));
878 	sin6.sin6_len = sizeof(struct sockaddr_in6);
879 	sin6.sin6_family = AF_INET6;
880 	sin6.sin6_addr = kin6addr_linklocal_allnodes;
881 	sin6.sin6_addr.s6_addr16[1] = htons(ifp->if_index);
882 	rt = rtpurelookup((struct sockaddr *)&sin6);
883 	if (rt != NULL && rt->rt_ifp == ifp) {
884 		--rt->rt_refcnt;
885 		rtrequest(RTM_DELETE, (struct sockaddr *)rt_key(rt),
886 		    rt->rt_gateway, rt_mask(rt), rt->rt_flags, 0);
887 	}
888 
889 	lwkt_replymsg(lmsg, 0);
890 }
891 
892 void
893 in6_ifdetach(struct ifnet *ifp)
894 {
895 	struct netmsg_base nmsg;
896 	struct lwkt_msg *lmsg = &nmsg.lmsg;
897 
898 	netmsg_init(&nmsg, NULL, &curthread->td_msgport, 0,
899 	    in6_ifdetach_dispatch);
900 	lmsg->u.ms_resultp = ifp;
901 	lwkt_domsg(netisr_cpuport(0), lmsg, 0);
902 }
903 
904 void
905 in6_get_tmpifid(struct ifnet *ifp, u_int8_t *retbuf, const u_int8_t *baseid,
906 		int generate)
907 {
908 	u_int8_t nullbuf[8];
909 	struct nd_ifinfo *ndi = ND_IFINFO(ifp);
910 
911 	bzero(nullbuf, sizeof(nullbuf));
912 	if (bcmp(ndi->randomid, nullbuf, sizeof(nullbuf)) == 0) {
913 		/* we've never created a random ID.  Create a new one. */
914 		generate = 1;
915 	}
916 
917 	if (generate) {
918 		bcopy(baseid, ndi->randomseed1, sizeof(ndi->randomseed1));
919 
920 		/* generate_tmp_ifid will update seedn and buf */
921 		generate_tmp_ifid(ndi->randomseed0, ndi->randomseed1,
922 				  ndi->randomid);
923 	}
924 	bcopy(ndi->randomid, retbuf, 8);
925 }
926 
927 static void
928 in6_tmpaddrtimer(void *arg __unused)
929 {
930 	struct lwkt_msg *lmsg = &in6_tmpaddrtimer_netmsg.lmsg;
931 
932 	KASSERT(mycpuid == 0, ("not on cpu0"));
933 	crit_enter();
934 	if (lmsg->ms_flags & MSGF_DONE)
935 		lwkt_sendmsg_oncpu(netisr_cpuport(0), lmsg);
936 	crit_exit();
937 }
938 
939 static void
940 in6_tmpaddrtimer_dispatch(netmsg_t nmsg)
941 {
942 	const struct ifnet_array *arr;
943 	struct nd_ifinfo *ndi;
944 	u_int8_t nullbuf[8];
945 	int i;
946 
947 	ASSERT_NETISR0;
948 
949 	crit_enter();
950 	lwkt_replymsg(&nmsg->lmsg, 0);  /* reply ASAP */
951 	crit_exit();
952 
953 	bzero(nullbuf, sizeof(nullbuf));
954 	arr = ifnet_array_get();
955 	for (i = 0; i < arr->ifnet_count; ++i) {
956 		struct ifnet *ifp = arr->ifnet_arr[i];
957 
958 		if (ifp->if_afdata[AF_INET6] == NULL)
959 			continue;
960 		ndi = ND_IFINFO(ifp);
961 		if (bcmp(ndi->randomid, nullbuf, sizeof(nullbuf)) != 0) {
962 			/*
963 			 * We've been generating a random ID on this interface.
964 			 * Create a new one.
965 			 */
966 			generate_tmp_ifid(ndi->randomseed0,
967 					  ndi->randomseed1,
968 					  ndi->randomid);
969 		}
970 	}
971 
972 	callout_reset(&in6_tmpaddrtimer_ch,
973 		      (ip6_temp_preferred_lifetime - ip6_desync_factor -
974 		       ip6_temp_regen_advance) * hz,
975 		      in6_tmpaddrtimer, NULL);
976 }
977 
978 /*
979  * Timer for regeneranation of temporary addresses randomize ID
980  */
981 void
982 in6_tmpaddrtimer_init(void)
983 {
984 	callout_init_mp(&in6_tmpaddrtimer_ch);
985 	netmsg_init(&in6_tmpaddrtimer_netmsg, NULL, &netisr_adone_rport,
986 	    MSGF_PRIORITY, in6_tmpaddrtimer_dispatch);
987 	callout_reset_bycpu(&in6_tmpaddrtimer_ch,
988 	    (ip6_temp_preferred_lifetime - ip6_desync_factor -
989 	     ip6_temp_regen_advance) * hz, in6_tmpaddrtimer, NULL, 0);
990 }
991