xref: /dragonfly/sys/netinet6/in6_ifattach.c (revision fca046ff)
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 static struct callout in6_tmpaddrtimer_ch;
69 static struct netmsg_base in6_tmpaddrtimer_netmsg;
70 
71 extern struct inpcbinfo ripcbinfo;
72 
73 static int get_rand_ifid (struct in6_addr *);
74 static int generate_tmp_ifid (u_int8_t *, const u_int8_t *, u_int8_t *);
75 static int get_hw_ifid (struct ifnet *, struct in6_addr *);
76 static int get_ifid (struct ifnet *, struct ifnet *, struct in6_addr *);
77 static int in6_ifattach_linklocal (struct ifnet *, struct ifnet *);
78 static int in6_ifattach_loopback (struct ifnet *);
79 
80 #define EUI64_GBIT	0x01
81 #define EUI64_UBIT	0x02
82 #define EUI64_TO_IFID(in6)	do {(in6)->s6_addr[8] ^= EUI64_UBIT; } while (0)
83 #define EUI64_GROUP(in6)	((in6)->s6_addr[8] & EUI64_GBIT)
84 #define EUI64_INDIVIDUAL(in6)	(!EUI64_GROUP(in6))
85 #define EUI64_LOCAL(in6)	((in6)->s6_addr[8] & EUI64_UBIT)
86 #define EUI64_UNIVERSAL(in6)	(!EUI64_LOCAL(in6))
87 
88 #define IFID_LOCAL(in6)		(!EUI64_LOCAL(in6))
89 #define IFID_UNIVERSAL(in6)	(!EUI64_UNIVERSAL(in6))
90 
91 /*
92  * Generate a last-resort interface identifier, when the machine has no
93  * IEEE802/EUI64 address sources.
94  * The goal here is to get an interface identifier that is
95  * (1) random enough and (2) does not change across reboot.
96  * We currently use MD5(hostname) for it.
97  */
98 static int
99 get_rand_ifid(struct in6_addr *in6)	/* upper 64bits are preserved */
100 {
101 	MD5_CTX ctxt;
102 	u_int8_t digest[16];
103 	int hostnamelen	= strlen(hostname);
104 
105 #if 0
106 	/* we need at least several letters as seed for ifid */
107 	if (hostnamelen < 3)
108 		return -1;
109 #endif
110 
111 	/* generate 8 bytes of pseudo-random value. */
112 	bzero(&ctxt, sizeof(ctxt));
113 	MD5Init(&ctxt);
114 	MD5Update(&ctxt, hostname, hostnamelen);
115 	MD5Final(digest, &ctxt);
116 
117 	/* assumes sizeof(digest) > sizeof(ifid) */
118 	bcopy(digest, &in6->s6_addr[8], 8);
119 
120 	/* make sure to set "u" bit to local, and "g" bit to individual. */
121 	in6->s6_addr[8] &= ~EUI64_GBIT;	/* g bit to "individual" */
122 	in6->s6_addr[8] |= EUI64_UBIT;	/* u bit to "local" */
123 
124 	/* convert EUI64 into IPv6 interface identifier */
125 	EUI64_TO_IFID(in6);
126 
127 	return 0;
128 }
129 
130 static int
131 generate_tmp_ifid(u_int8_t *seed0, const u_int8_t *seed1, u_int8_t *ret)
132 {
133 	MD5_CTX ctxt;
134 	u_int8_t seed[16], digest[16], nullbuf[8];
135 	u_int32_t val32;
136 	struct timeval tv;
137 
138 	/* If there's no hisotry, start with a random seed. */
139 	bzero(nullbuf, sizeof(nullbuf));
140 	if (bcmp(nullbuf, seed0, sizeof(nullbuf)) == 0) {
141 		int i;
142 
143 		for (i = 0; i < 2; i++) {
144 			microtime(&tv);
145 			val32 = krandom() ^ tv.tv_usec;
146 			bcopy(&val32, seed + sizeof(val32) * i, sizeof(val32));
147 		}
148 	} else {
149 		bcopy(seed0, seed, 8);
150 	}
151 
152 	/* copy the right-most 64-bits of the given address */
153 	/* XXX assumption on the size of IFID */
154 	bcopy(seed1, &seed[8], 8);
155 
156 	if (0) {		/* for debugging purposes only */
157 		int i;
158 
159 		kprintf("generate_tmp_ifid: new randomized ID from: ");
160 		for (i = 0; i < 16; i++)
161 			kprintf("%02x", seed[i]);
162 		kprintf(" ");
163 	}
164 
165 	/* generate 16 bytes of pseudo-random value. */
166 	bzero(&ctxt, sizeof(ctxt));
167 	MD5Init(&ctxt);
168 	MD5Update(&ctxt, seed, sizeof(seed));
169 	MD5Final(digest, &ctxt);
170 
171 	/*
172 	 * RFC 3041 3.2.1. (3)
173 	 * Take the left-most 64-bits of the MD5 digest and set bit 6 (the
174 	 * left-most bit is numbered 0) to zero.
175 	 */
176 	bcopy(digest, ret, 8);
177 	ret[0] &= ~EUI64_UBIT;
178 
179 	/*
180 	 * XXX: we'd like to ensure that the generated value is not zero
181 	 * for simplicity.  If the caclculated digest happens to be zero,
182 	 * use a random non-zero value as the last resort.
183 	 */
184 	if (bcmp(nullbuf, ret, sizeof(nullbuf)) == 0) {
185 		log(LOG_INFO,
186 		    "generate_tmp_ifid: computed MD5 value is zero.\n");
187 
188 		microtime(&tv);
189 		val32 = krandom() ^ tv.tv_usec;
190 		val32 = 1 + (val32 % (0xffffffff - 1));
191 	}
192 
193 	/*
194 	 * RFC 3041 3.2.1. (4)
195 	 * Take the rightmost 64-bits of the MD5 digest and save them in
196 	 * stable storage as the history value to be used in the next
197 	 * iteration of the algorithm.
198 	 */
199 	bcopy(&digest[8], seed0, 8);
200 
201 	if (0) {		/* for debugging purposes only */
202 		int i;
203 
204 		kprintf("to: ");
205 		for (i = 0; i < 16; i++)
206 			kprintf("%02x", digest[i]);
207 		kprintf("\n");
208 	}
209 
210 	return 0;
211 }
212 
213 /*
214  * Get interface identifier for the specified interface.
215  * XXX assumes single sockaddr_dl (AF_LINK address) per an interface
216  */
217 static int
218 get_hw_ifid(struct ifnet *ifp,
219 	    struct in6_addr *in6)	/* upper 64bits are preserved */
220 {
221 	struct ifaddr_container *ifac;
222 	struct sockaddr_dl *sdl;
223 	u_int8_t *addr;
224 	size_t addrlen;
225 	static u_int8_t allzero[8] = { 0, 0, 0, 0, 0, 0, 0, 0 };
226 	static u_int8_t allone[8] =
227 		{ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
228 
229 	TAILQ_FOREACH(ifac, &ifp->if_addrheads[mycpuid], ifa_link) {
230 		struct ifaddr *ifa = ifac->ifa;
231 
232 		if (ifa->ifa_addr->sa_family != AF_LINK)
233 			continue;
234 		sdl = (struct sockaddr_dl *)ifa->ifa_addr;
235 		if (sdl == NULL)
236 			continue;
237 		if (sdl->sdl_alen == 0)
238 			continue;
239 
240 		goto found;
241 	}
242 
243 	return -1;
244 
245 found:
246 	addr = LLADDR(sdl);
247 	addrlen = sdl->sdl_alen;
248 
249 	/* get EUI64 */
250 	switch (ifp->if_type) {
251 	case IFT_ETHER:
252 	case IFT_ATM:
253 	case IFT_IEEE1394:
254 #ifdef IFT_IEEE80211
255 	case IFT_IEEE80211:
256 #endif
257 		/* IEEE802/EUI64 cases - what others? */
258 		/* IEEE1394 uses 16byte length address starting with EUI64 */
259 		if (addrlen > 8)
260 			addrlen = 8;
261 
262 		/* look at IEEE802/EUI64 only */
263 		if (addrlen != 8 && addrlen != 6)
264 			return -1;
265 
266 		/*
267 		 * check for invalid MAC address - on bsdi, we see it a lot
268 		 * since wildboar configures all-zero MAC on pccard before
269 		 * card insertion.
270 		 */
271 		if (bcmp(addr, allzero, addrlen) == 0)
272 			return -1;
273 		if (bcmp(addr, allone, addrlen) == 0)
274 			return -1;
275 
276 		/* make EUI64 address */
277 		if (addrlen == 8)
278 			bcopy(addr, &in6->s6_addr[8], 8);
279 		else if (addrlen == 6) {
280 			in6->s6_addr[8] = addr[0];
281 			in6->s6_addr[9] = addr[1];
282 			in6->s6_addr[10] = addr[2];
283 			in6->s6_addr[11] = 0xff;
284 			in6->s6_addr[12] = 0xfe;
285 			in6->s6_addr[13] = addr[3];
286 			in6->s6_addr[14] = addr[4];
287 			in6->s6_addr[15] = addr[5];
288 		}
289 		break;
290 	case IFT_GIF:
291 #ifdef IFT_STF
292 	case IFT_STF:
293 #endif
294 		/*
295 		 * RFC2893 says: "SHOULD use IPv4 address as ifid source".
296 		 * however, IPv4 address is not very suitable as unique
297 		 * identifier source (can be renumbered).
298 		 * we don't do this.
299 		 */
300 		return -1;
301 
302 	default:
303 		return -1;
304 	}
305 
306 	/* sanity check: g bit must not indicate "group" */
307 	if (EUI64_GROUP(in6))
308 		return -1;
309 
310 	/* convert EUI64 into IPv6 interface identifier */
311 	EUI64_TO_IFID(in6);
312 
313 	/*
314 	 * sanity check: ifid must not be all zero, avoid conflict with
315 	 * subnet router anycast
316 	 */
317 	if ((in6->s6_addr[8] & ~(EUI64_GBIT | EUI64_UBIT)) == 0x00 &&
318 	    bcmp(&in6->s6_addr[9], allzero, 7) == 0) {
319 		return -1;
320 	}
321 
322 	return 0;
323 }
324 
325 /*
326  * Get interface identifier for the specified interface.  If it is not
327  * available on ifp0, borrow interface identifier from other information
328  * sources.
329  */
330 static int
331 get_ifid(struct ifnet *ifp0,
332 	 struct ifnet *altifp,	/* secondary EUI64 source */
333 	 struct in6_addr *in6)
334 {
335 	const struct ifnet_array *arr;
336 	int i;
337 
338 	/* first, try to get it from the interface itself */
339 	if (get_hw_ifid(ifp0, in6) == 0) {
340 		nd6log((LOG_DEBUG, "%s: got interface identifier from itself\n",
341 		    if_name(ifp0)));
342 		goto success;
343 	}
344 
345 	/* try secondary EUI64 source. this basically is for ATM PVC */
346 	if (altifp && get_hw_ifid(altifp, in6) == 0) {
347 		nd6log((LOG_DEBUG, "%s: got interface identifier from %s\n",
348 		    if_name(ifp0), if_name(altifp)));
349 		goto success;
350 	}
351 
352 	/* next, try to get it from some other hardware interface */
353 	arr = ifnet_array_get();
354 	for (i = 0; i < arr->ifnet_count; ++i) {
355 		struct ifnet *ifp = arr->ifnet_arr[i];
356 
357 		if (ifp == ifp0)
358 			continue;
359 		if (get_hw_ifid(ifp, in6) != 0)
360 			continue;
361 
362 		/*
363 		 * to borrow ifid from other interface, ifid needs to be
364 		 * globally unique
365 		 */
366 		if (IFID_UNIVERSAL(in6)) {
367 			nd6log((LOG_DEBUG,
368 			    "%s: borrow interface identifier from %s\n",
369 			    if_name(ifp0), if_name(ifp)));
370 			goto success;
371 		}
372 	}
373 
374 	/* last resort: get from random number source */
375 	if (get_rand_ifid(in6) == 0) {
376 		nd6log((LOG_DEBUG,
377 		    "%s: interface identifier generated by random number\n",
378 		    if_name(ifp0)));
379 		goto success;
380 	}
381 
382 	kprintf("%s: failed to get interface identifier\n", if_name(ifp0));
383 	return -1;
384 
385 success:
386 	nd6log((LOG_INFO, "%s: ifid: "
387 		"%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x\n",
388 		if_name(ifp0),
389 		in6->s6_addr[8], in6->s6_addr[9],
390 		in6->s6_addr[10], in6->s6_addr[11],
391 		in6->s6_addr[12], in6->s6_addr[13],
392 		in6->s6_addr[14], in6->s6_addr[15]));
393 	return 0;
394 }
395 
396 static int
397 in6_ifattach_linklocal(struct ifnet *ifp,
398 		       struct ifnet *altifp)	/* secondary EUI64 source */
399 {
400 	struct in6_ifaddr *ia;
401 	struct in6_aliasreq ifra;
402 	struct nd_prefix pr0;
403 	int i, error;
404 
405 	/*
406 	 * configure link-local address.
407 	 */
408 	bzero(&ifra, sizeof(ifra));
409 
410 	/*
411 	 * in6_update_ifa() does not use ifra_name, but we accurately set it
412 	 * for safety.
413 	 */
414 	strncpy(ifra.ifra_name, if_name(ifp), sizeof(ifra.ifra_name));
415 
416 	ifra.ifra_addr.sin6_family = AF_INET6;
417 	ifra.ifra_addr.sin6_len = sizeof(struct sockaddr_in6);
418 	ifra.ifra_addr.sin6_addr.s6_addr16[0] = htons(0xfe80);
419 	ifra.ifra_addr.sin6_addr.s6_addr16[1] = htons(ifp->if_index); /* XXX */
420 	ifra.ifra_addr.sin6_addr.s6_addr32[1] = 0;
421 	if (ifp->if_flags & IFF_LOOPBACK) {
422 		ifra.ifra_addr.sin6_addr.s6_addr32[2] = 0;
423 		ifra.ifra_addr.sin6_addr.s6_addr32[3] = htonl(1);
424 	} else {
425 		if (get_ifid(ifp, altifp, &ifra.ifra_addr.sin6_addr) != 0) {
426 			nd6log((LOG_ERR,
427 			    "%s: no ifid available\n", if_name(ifp)));
428 			return -1;
429 		}
430 	}
431 
432 	ifra.ifra_prefixmask.sin6_len = sizeof(struct sockaddr_in6);
433 	ifra.ifra_prefixmask.sin6_family = AF_INET6;
434 	ifra.ifra_prefixmask.sin6_addr = in6mask64;
435 
436 	/* link-local addresses should NEVER expire. */
437 	ifra.ifra_lifetime.ia6t_vltime = ND6_INFINITE_LIFETIME;
438 	ifra.ifra_lifetime.ia6t_pltime = ND6_INFINITE_LIFETIME;
439 
440 	/*
441 	 * Do not let in6_update_ifa() do DAD, since we need a random delay
442 	 * before sending an NS at the first time the interface becomes up.
443 	 * Instead, in6_if_up() will start DAD with a proper random delay.
444 	 */
445 	ifra.ifra_flags |= IN6_IFF_NODAD;
446 
447 	/*
448 	 * Now call in6_update_ifa() to do a bunch of procedures to configure
449 	 * a link-local address. We can set NULL to the 3rd argument, because
450 	 * we know there's no other link-local address on the interface
451 	 * and therefore we are adding one (instead of updating one).
452 	 */
453 	if ((error = in6_update_ifa(ifp, &ifra, NULL)) != 0) {
454 		/*
455 		 * XXX: When the interface does not support IPv6, this call
456 		 * would fail in the SIOCSIFADDR ioctl.  I believe the
457 		 * notification is rather confusing in this case, so just
458 		 * suppress it.  (jinmei@kame.net 20010130)
459 		 */
460 		if (error != EAFNOSUPPORT)
461 			log(LOG_NOTICE, "in6_ifattach_linklocal: failed to "
462 			    "configure a link-local address on %s "
463 			    "(errno=%d)\n",
464 			    if_name(ifp), error);
465 		return (-1);
466 	}
467 
468 	/*
469 	 * Adjust ia6_flags so that in6_if_up will perform DAD.
470 	 * XXX: Some P2P interfaces seem not to send packets just after
471 	 * becoming up, so we skip p2p interfaces for safety.
472 	 */
473 	ia = in6ifa_ifpforlinklocal(ifp, 0); /* ia must not be NULL */
474 #ifdef DIAGNOSTIC
475 	if (!ia) {
476 		panic("ia == NULL in in6_ifattach_linklocal");
477 		/* NOTREACHED */
478 	}
479 #endif
480 	if (in6if_do_dad(ifp) && !(ifp->if_flags & IFF_POINTOPOINT)) {
481 		ia->ia6_flags &= ~IN6_IFF_NODAD;
482 		ia->ia6_flags |= IN6_IFF_TENTATIVE;
483 	}
484 
485 	/*
486 	 * Make the link-local prefix (fe80::%link/64) as on-link.
487 	 * Since we'd like to manage prefixes separately from addresses,
488 	 * we make an ND6 prefix structure for the link-local prefix,
489 	 * and add it to the prefix list as a never-expire prefix.
490 	 * XXX: this change might affect some existing code base...
491 	 */
492 	bzero(&pr0, sizeof(pr0));
493 	pr0.ndpr_ifp = ifp;
494 	/* this should be 64 at this moment. */
495 	pr0.ndpr_plen = in6_mask2len(&ifra.ifra_prefixmask.sin6_addr, NULL);
496 	pr0.ndpr_mask = ifra.ifra_prefixmask.sin6_addr;
497 	pr0.ndpr_prefix = ifra.ifra_addr;
498 	/* apply the mask for safety. (nd6_prelist_add will apply it again) */
499 	for (i = 0; i < 4; i++) {
500 		pr0.ndpr_prefix.sin6_addr.s6_addr32[i] &=
501 		    in6mask64.s6_addr32[i];
502 	}
503 	/*
504 	 * Initialize parameters.  The link-local prefix must always be
505 	 * on-link, and its lifetimes never expire.
506 	 */
507 	pr0.ndpr_raf_onlink = 1;
508 	pr0.ndpr_raf_auto = 1;	/* probably meaningless */
509 	pr0.ndpr_vltime = ND6_INFINITE_LIFETIME;
510 	pr0.ndpr_pltime = ND6_INFINITE_LIFETIME;
511 	/*
512 	 * Since there is no other link-local addresses, nd6_prefix_lookup()
513 	 * probably returns NULL.  However, we cannot always expect the result.
514 	 * For example, if we first remove the (only) existing link-local
515 	 * address, and then reconfigure another one, the prefix is still
516 	 * valid with referring to the old link-local address.
517 	 */
518 	if (nd6_prefix_lookup(&pr0) == NULL) {
519 		if ((error = nd6_prelist_add(&pr0, NULL, NULL)) != 0)
520 			return (error);
521 	}
522 
523 	return 0;
524 }
525 
526 static int
527 in6_ifattach_loopback(struct ifnet *ifp)	/* must be IFT_LOOP */
528 {
529 	struct in6_aliasreq ifra;
530 	int error;
531 
532 	bzero(&ifra, sizeof(ifra));
533 
534 	/*
535 	 * in6_update_ifa() does not use ifra_name, but we accurately set it
536 	 * for safety.
537 	 */
538 	strncpy(ifra.ifra_name, if_name(ifp), sizeof(ifra.ifra_name));
539 
540 	ifra.ifra_prefixmask.sin6_len = sizeof(struct sockaddr_in6);
541 	ifra.ifra_prefixmask.sin6_family = AF_INET6;
542 	ifra.ifra_prefixmask.sin6_addr = in6mask128;
543 
544 	/*
545 	 * Always initialize ia_dstaddr (= broadcast address) to loopback
546 	 * address.  Follows IPv4 practice - see in_ifinit().
547 	 */
548 	ifra.ifra_dstaddr.sin6_len = sizeof(struct sockaddr_in6);
549 	ifra.ifra_dstaddr.sin6_family = AF_INET6;
550 	ifra.ifra_dstaddr.sin6_addr = kin6addr_loopback;
551 
552 	ifra.ifra_addr.sin6_len = sizeof(struct sockaddr_in6);
553 	ifra.ifra_addr.sin6_family = AF_INET6;
554 	ifra.ifra_addr.sin6_addr = kin6addr_loopback;
555 
556 	/* the loopback  address should NEVER expire. */
557 	ifra.ifra_lifetime.ia6t_vltime = ND6_INFINITE_LIFETIME;
558 	ifra.ifra_lifetime.ia6t_pltime = ND6_INFINITE_LIFETIME;
559 
560 	/* we don't need to perform DAD on loopback interfaces. */
561 	ifra.ifra_flags |= IN6_IFF_NODAD;
562 
563 	/* skip registration to the prefix list. XXX should be temporary. */
564 	ifra.ifra_flags |= IN6_IFF_NOPFX;
565 
566 	/*
567 	 * We are sure that this is a newly assigned address, so we can set
568 	 * NULL to the 3rd arg.
569 	 */
570 	if ((error = in6_update_ifa(ifp, &ifra, NULL)) != 0) {
571 		log(LOG_ERR, "in6_ifattach_loopback: failed to configure "
572 		    "the loopback address on %s (errno=%d)\n",
573 		    if_name(ifp), error);
574 		return (-1);
575 	}
576 
577 	return 0;
578 }
579 
580 /*
581  * compute NI group address, based on the current hostname setting.
582  * see draft-ietf-ipngwg-icmp-name-lookup-* (04 and later).
583  *
584  * when ifp == NULL, the caller is responsible for filling scopeid.
585  */
586 int
587 in6_nigroup(struct ifnet *ifp, const char *name, int namelen,
588 	    struct in6_addr *in6)
589 {
590 	const char *p;
591 	u_char *q;
592 	MD5_CTX ctxt;
593 	u_int8_t digest[16];
594 	char l;
595 	char n[64];	/* a single label must not exceed 63 chars */
596 
597 	if (!namelen || !name)
598 		return -1;
599 
600 	p = name;
601 	while (p && *p && *p != '.' && p - name < namelen)
602 		p++;
603 	if (p - name > sizeof(n) - 1)
604 		return -1;	/* label too long */
605 	l = p - name;
606 	strncpy(n, name, l);
607 	n[(int)l] = '\0';
608 	for (q = n; *q; q++) {
609 		if ('A' <= *q && *q <= 'Z')
610 			*q = *q - 'A' + 'a';
611 	}
612 
613 	/* generate 8 bytes of pseudo-random value. */
614 	bzero(&ctxt, sizeof(ctxt));
615 	MD5Init(&ctxt);
616 	MD5Update(&ctxt, &l, sizeof(l));
617 	MD5Update(&ctxt, n, l);
618 	MD5Final(digest, &ctxt);
619 
620 	bzero(in6, sizeof(*in6));
621 	in6->s6_addr16[0] = htons(0xff02);
622 	if (ifp)
623 		in6->s6_addr16[1] = htons(ifp->if_index);
624 	in6->s6_addr8[11] = 2;
625 	bcopy(digest, &in6->s6_addr32[3], sizeof(in6->s6_addr32[3]));
626 
627 	return 0;
628 }
629 
630 struct netmsg_nigroup {
631 	struct netmsg_base	nmsg;
632 	const char		*name;
633 	int			namelen;
634 };
635 
636 static void
637 in6_nigroup_attach_dispatch(netmsg_t msg)
638 {
639 	struct netmsg_nigroup *nmsg = (struct netmsg_nigroup *)msg;
640 	struct sockaddr_in6 mltaddr;
641 	struct in6_multi *in6m;
642 	const struct ifnet_array *arr;
643 	int error, i;
644 
645 	bzero(&mltaddr, sizeof(mltaddr));
646 	mltaddr.sin6_family = AF_INET6;
647 	mltaddr.sin6_len = sizeof(struct sockaddr_in6);
648 	if (in6_nigroup(NULL, nmsg->name, nmsg->namelen,
649 	    &mltaddr.sin6_addr) != 0)
650 		goto done;
651 
652 	arr = ifnet_array_get();
653 	for (i = 0; i < arr->ifnet_count; ++i) {
654 		struct ifnet *ifp = arr->ifnet_arr[i];
655 
656 		mltaddr.sin6_addr.s6_addr16[1] = htons(ifp->if_index);
657 		in6m = IN6_LOOKUP_MULTI(&mltaddr.sin6_addr, ifp);
658 		if (!in6m) {
659 			if (!in6_addmulti(&mltaddr.sin6_addr, ifp, &error)) {
660 				nd6log((LOG_ERR, "%s: failed to join %s "
661 				    "(errno=%d)\n", if_name(ifp),
662 				    ip6_sprintf(&mltaddr.sin6_addr),
663 				    error));
664 			}
665 		}
666 	}
667 done:
668 	lwkt_replymsg(&nmsg->nmsg.lmsg, 0);
669 }
670 
671 void
672 in6_nigroup_attach(const char *name, int namelen)
673 {
674 	struct netmsg_nigroup nmsg;
675 
676 	netmsg_init(&nmsg.nmsg, NULL, &curthread->td_msgport, 0,
677 	    in6_nigroup_attach_dispatch);
678 	nmsg.name = name;
679 	nmsg.namelen = namelen;
680 	lwkt_domsg(netisr_cpuport(0), &nmsg.nmsg.lmsg, 0);
681 }
682 
683 static void
684 in6_nigroup_detach_dispatch(netmsg_t msg)
685 {
686 	struct netmsg_nigroup *nmsg = (struct netmsg_nigroup *)msg;
687 	struct sockaddr_in6 mltaddr;
688 	struct in6_multi *in6m;
689 	const struct ifnet_array *arr;
690 	int i;
691 
692 	bzero(&mltaddr, sizeof(mltaddr));
693 	mltaddr.sin6_family = AF_INET6;
694 	mltaddr.sin6_len = sizeof(struct sockaddr_in6);
695 	if (in6_nigroup(NULL, nmsg->name, nmsg->namelen,
696 	    &mltaddr.sin6_addr) != 0)
697 		goto done;
698 
699 	arr = ifnet_array_get();
700 	for (i = 0; i < arr->ifnet_count; ++i) {
701 		struct ifnet *ifp = arr->ifnet_arr[i];
702 
703 		mltaddr.sin6_addr.s6_addr16[1] = htons(ifp->if_index);
704 		in6m = IN6_LOOKUP_MULTI(&mltaddr.sin6_addr, ifp);
705 		if (in6m)
706 			in6_delmulti(in6m);
707 	}
708 done:
709 	lwkt_replymsg(&nmsg->nmsg.lmsg, 0);
710 }
711 
712 void
713 in6_nigroup_detach(const char *name, int namelen)
714 {
715 	struct netmsg_nigroup nmsg;
716 
717 	netmsg_init(&nmsg.nmsg, NULL, &curthread->td_msgport, 0,
718 	    in6_nigroup_detach_dispatch);
719 	nmsg.name = name;
720 	nmsg.namelen = namelen;
721 	lwkt_domsg(netisr_cpuport(0), &nmsg.nmsg.lmsg, 0);
722 }
723 
724 /*
725  * XXX multiple loopback interface needs more care.  for instance,
726  * nodelocal address needs to be configured onto only one of them.
727  * XXX multiple link-local address case
728  */
729 void
730 in6_ifattach(struct ifnet *ifp,
731 	     struct ifnet *altifp)	/* secondary EUI64 source */
732 {
733 	struct in6_addr in6;
734 
735 	/* some of the interfaces are inherently not IPv6 capable */
736 	switch (ifp->if_type) {
737 #ifdef IFT_BRIDGE	/* OpenBSD 2.8, NetBSD 1.6 */
738 	case IFT_BRIDGE:
739 		return;
740 #endif
741 	case IFT_PFLOG:
742 	case IFT_PFSYNC:
743 	case IFT_CARP:
744 		return;
745 	}
746 
747 	/*
748 	 * quirks based on interface type
749 	 */
750 	switch (ifp->if_type) {
751 #ifdef IFT_STF
752 	case IFT_STF:
753 		/*
754 		 * 6to4 interface is a very special kind of beast.
755 		 * no multicast, no linklocal.  RFC2529 specifies how to make
756 		 * linklocals for 6to4 interface, but there's no use and
757 		 * it is rather harmful to have one.
758 		 */
759 		goto statinit;
760 #endif
761 	default:
762 		break;
763 	}
764 
765 	/*
766 	 * usually, we require multicast capability to the interface
767 	 */
768 	if (!(ifp->if_flags & IFF_MULTICAST)) {
769 		log(LOG_INFO, "in6_ifattach: "
770 		    "%s is not multicast capable, IPv6 not enabled\n",
771 		    if_name(ifp));
772 		return;
773 	}
774 
775 	/*
776 	 * assign loopback address for loopback interface.
777 	 * XXX multiple loopback interface case.
778 	 */
779 	if (ifp->if_flags & IFF_LOOPBACK) {
780 		in6 = kin6addr_loopback;
781 		if (in6ifa_ifpwithaddr(ifp, &in6) == NULL) {
782 			if (in6_ifattach_loopback(ifp) != 0)
783 				return;
784 		}
785 	}
786 
787 	/*
788 	 * assign a link-local address, if there's none.
789 	 */
790 	if ((ND_IFINFO(ifp)->flags & ND6_IFF_AUTO_LINKLOCAL) &&
791 	    in6ifa_ifpforlinklocal(ifp, 0) == NULL) {
792 		in6_ifattach_linklocal(ifp, altifp);
793 	}
794 
795 #ifdef IFT_STF			/* XXX */
796 statinit:
797 #endif
798 
799 	/* update dynamically. */
800 	if (in6_maxmtu < ifp->if_mtu)
801 		in6_maxmtu = ifp->if_mtu;
802 }
803 
804 /*
805  * NOTE: in6_ifdetach() does not support loopback if at this moment.
806  */
807 static void
808 in6_ifdetach_dispatch(netmsg_t nmsg)
809 {
810 	struct lwkt_msg *lmsg = &nmsg->lmsg;
811 	struct ifnet *ifp = lmsg->u.ms_resultp;
812 	struct ifaddr_container *ifac, *next;
813 	struct rtentry *rt;
814 	struct sockaddr_in6 sin6;
815 	struct in6_multi *in6m, *in6m_next;
816 
817 	ASSERT_NETISR0;
818 
819 	/* remove neighbor management table */
820 	nd6_purge(ifp);
821 
822 	/* nuke any of IPv6 addresses we have */
823 	TAILQ_FOREACH_MUTABLE(ifac, &ifp->if_addrheads[mycpuid], ifa_link,
824 	    next) {
825 		struct ifaddr *ifa = ifac->ifa;
826 
827 		if (ifa->ifa_addr->sa_family != AF_INET6)
828 			continue;
829 		in6_purgeaddr(ifa);
830 	}
831 
832 	/*
833 	 * XXX
834 	 * These were code trying to nuke inet6 addresses again, but all
835 	 * inet6 addresses must have been deleted above; use assertion.
836 	 */
837 	TAILQ_FOREACH(ifac, &ifp->if_addrheads[mycpuid], ifa_link) {
838 		KASSERT(ifac->ifa->ifa_addr->sa_family != AF_INET6,
839 		    ("still has inet6 addr"));
840 	}
841 
842 	/* leave from all multicast groups joined */
843 	in6_pcbpurgeif0(&ripcbinfo, ifp);
844 	in6_pcbpurgeif0(&udbinfo[0], ifp);
845 	for (in6m = LIST_FIRST(&in6_multihead); in6m; in6m = in6m_next) {
846 		in6m_next = LIST_NEXT(in6m, in6m_entry);
847 		if (in6m->in6m_ifp != ifp)
848 			continue;
849 		in6_delmulti(in6m);
850 		in6m = NULL;
851 	}
852 
853 	/*
854 	 * remove neighbor management table.  we call it twice just to make
855 	 * sure we nuke everything.  maybe we need just one call.
856 	 * XXX: since the first call did not release addresses, some prefixes
857 	 * might remain.  We should call nd6_purge() again to release the
858 	 * prefixes after removing all addresses above.
859 	 * (Or can we just delay calling nd6_purge until at this point?)
860 	 */
861 	nd6_purge(ifp);
862 
863 	/* remove route to link-local allnodes multicast (ff02::1) */
864 	bzero(&sin6, sizeof(sin6));
865 	sin6.sin6_len = sizeof(struct sockaddr_in6);
866 	sin6.sin6_family = AF_INET6;
867 	sin6.sin6_addr = kin6addr_linklocal_allnodes;
868 	sin6.sin6_addr.s6_addr16[1] = htons(ifp->if_index);
869 	rt = rtpurelookup((struct sockaddr *)&sin6);
870 	if (rt != NULL && rt->rt_ifp == ifp) {
871 		--rt->rt_refcnt;
872 		rtrequest(RTM_DELETE, (struct sockaddr *)rt_key(rt),
873 		    rt->rt_gateway, rt_mask(rt), rt->rt_flags, 0);
874 	}
875 
876 	lwkt_replymsg(lmsg, 0);
877 }
878 
879 void
880 in6_ifdetach(struct ifnet *ifp)
881 {
882 	struct netmsg_base nmsg;
883 	struct lwkt_msg *lmsg = &nmsg.lmsg;
884 
885 	netmsg_init(&nmsg, NULL, &curthread->td_msgport, 0,
886 	    in6_ifdetach_dispatch);
887 	lmsg->u.ms_resultp = ifp;
888 	lwkt_domsg(netisr_cpuport(0), lmsg, 0);
889 }
890 
891 void
892 in6_get_tmpifid(struct ifnet *ifp, u_int8_t *retbuf, const u_int8_t *baseid,
893 		int generate)
894 {
895 	u_int8_t nullbuf[8];
896 	struct nd_ifinfo *ndi = ND_IFINFO(ifp);
897 
898 	bzero(nullbuf, sizeof(nullbuf));
899 	if (bcmp(ndi->randomid, nullbuf, sizeof(nullbuf)) == 0) {
900 		/* we've never created a random ID.  Create a new one. */
901 		generate = 1;
902 	}
903 
904 	if (generate) {
905 		bcopy(baseid, ndi->randomseed1, sizeof(ndi->randomseed1));
906 
907 		/* generate_tmp_ifid will update seedn and buf */
908 		generate_tmp_ifid(ndi->randomseed0, ndi->randomseed1,
909 				  ndi->randomid);
910 	}
911 	bcopy(ndi->randomid, retbuf, 8);
912 }
913 
914 static void
915 in6_tmpaddrtimer(void *arg __unused)
916 {
917 	struct lwkt_msg *lmsg = &in6_tmpaddrtimer_netmsg.lmsg;
918 
919 	KASSERT(mycpuid == 0, ("not on cpu0"));
920 	crit_enter();
921 	if (lmsg->ms_flags & MSGF_DONE)
922 		lwkt_sendmsg_oncpu(netisr_cpuport(0), lmsg);
923 	crit_exit();
924 }
925 
926 static void
927 in6_tmpaddrtimer_dispatch(netmsg_t nmsg)
928 {
929 	const struct ifnet_array *arr;
930 	struct nd_ifinfo *ndi;
931 	u_int8_t nullbuf[8];
932 	int i;
933 
934 	ASSERT_NETISR0;
935 
936 	crit_enter();
937 	lwkt_replymsg(&nmsg->lmsg, 0);  /* reply ASAP */
938 	crit_exit();
939 
940 	bzero(nullbuf, sizeof(nullbuf));
941 	arr = ifnet_array_get();
942 	for (i = 0; i < arr->ifnet_count; ++i) {
943 		struct ifnet *ifp = arr->ifnet_arr[i];
944 
945 		if (ifp->if_afdata[AF_INET6] == NULL)
946 			continue;
947 		ndi = ND_IFINFO(ifp);
948 		if (bcmp(ndi->randomid, nullbuf, sizeof(nullbuf)) != 0) {
949 			/*
950 			 * We've been generating a random ID on this interface.
951 			 * Create a new one.
952 			 */
953 			generate_tmp_ifid(ndi->randomseed0,
954 					  ndi->randomseed1,
955 					  ndi->randomid);
956 		}
957 	}
958 
959 	callout_reset(&in6_tmpaddrtimer_ch,
960 		      (ip6_temp_preferred_lifetime - ip6_desync_factor -
961 		       ip6_temp_regen_advance) * hz,
962 		      in6_tmpaddrtimer, NULL);
963 }
964 
965 /*
966  * Timer for regeneranation of temporary addresses randomize ID
967  */
968 void
969 in6_tmpaddrtimer_init(void)
970 {
971 	callout_init_mp(&in6_tmpaddrtimer_ch);
972 	netmsg_init(&in6_tmpaddrtimer_netmsg, NULL, &netisr_adone_rport,
973 	    MSGF_PRIORITY, in6_tmpaddrtimer_dispatch);
974 	callout_reset_bycpu(&in6_tmpaddrtimer_ch,
975 	    (ip6_temp_preferred_lifetime - ip6_desync_factor -
976 	     ip6_temp_regen_advance) * hz, in6_tmpaddrtimer, NULL, 0);
977 }
978