xref: /freebsd/sys/netinet6/in6_ifattach.c (revision 37f878f56c07f3c298351acae5fe0c9afe936d79)
1 /*	$FreeBSD$	*/
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 
42 #include <net/if.h>
43 #include <net/if_dl.h>
44 #include <net/if_types.h>
45 #include <net/route.h>
46 
47 #include <netinet/in.h>
48 #include <netinet/in_var.h>
49 #include <netinet/if_ether.h>
50 #include <netinet/in_pcb.h>
51 
52 #include <netinet/ip6.h>
53 #include <netinet6/ip6_var.h>
54 #include <netinet6/in6_var.h>
55 #include <netinet6/in6_pcb.h>
56 #include <netinet6/in6_ifattach.h>
57 #include <netinet6/ip6_var.h>
58 #include <netinet6/nd6.h>
59 #include <netinet6/scope6_var.h>
60 
61 unsigned long in6_maxmtu = 0;
62 
63 #ifdef IP6_AUTO_LINKLOCAL
64 int ip6_auto_linklocal = IP6_AUTO_LINKLOCAL;
65 #else
66 int ip6_auto_linklocal = 1;	/* enable by default */
67 #endif
68 
69 struct callout in6_tmpaddrtimer_ch;
70 
71 extern struct inpcbinfo udbinfo;
72 extern struct inpcbinfo ripcbinfo;
73 
74 static int get_rand_ifid __P((struct ifnet *, struct in6_addr *));
75 static int generate_tmp_ifid __P((u_int8_t *, const u_int8_t *, u_int8_t *));
76 static int get_ifid __P((struct ifnet *, struct ifnet *, struct in6_addr *));
77 static int in6_ifattach_linklocal __P((struct ifnet *, struct ifnet *));
78 static int in6_ifattach_loopback __P((struct ifnet *));
79 static void in6_purgemaddrs __P((struct ifnet *));
80 
81 #define EUI64_GBIT	0x01
82 #define EUI64_UBIT	0x02
83 #define EUI64_TO_IFID(in6)	do {(in6)->s6_addr[8] ^= EUI64_UBIT; } while (0)
84 #define EUI64_GROUP(in6)	((in6)->s6_addr[8] & EUI64_GBIT)
85 #define EUI64_INDIVIDUAL(in6)	(!EUI64_GROUP(in6))
86 #define EUI64_LOCAL(in6)	((in6)->s6_addr[8] & EUI64_UBIT)
87 #define EUI64_UNIVERSAL(in6)	(!EUI64_LOCAL(in6))
88 
89 #define IFID_LOCAL(in6)		(!EUI64_LOCAL(in6))
90 #define IFID_UNIVERSAL(in6)	(!EUI64_UNIVERSAL(in6))
91 
92 /*
93  * Generate a last-resort interface identifier, when the machine has no
94  * IEEE802/EUI64 address sources.
95  * The goal here is to get an interface identifier that is
96  * (1) random enough and (2) does not change across reboot.
97  * We currently use MD5(hostname) for it.
98  */
99 static int
100 get_rand_ifid(ifp, in6)
101 	struct ifnet *ifp;
102 	struct in6_addr *in6;	/* upper 64bits are preserved */
103 {
104 	MD5_CTX ctxt;
105 	u_int8_t digest[16];
106 	int hostnamelen	= strlen(hostname);
107 
108 #if 0
109 	/* we need at least several letters as seed for ifid */
110 	if (hostnamelen < 3)
111 		return -1;
112 #endif
113 
114 	/* generate 8 bytes of pseudo-random value. */
115 	bzero(&ctxt, sizeof(ctxt));
116 	MD5Init(&ctxt);
117 	MD5Update(&ctxt, hostname, hostnamelen);
118 	MD5Final(digest, &ctxt);
119 
120 	/* assumes sizeof(digest) > sizeof(ifid) */
121 	bcopy(digest, &in6->s6_addr[8], 8);
122 
123 	/* make sure to set "u" bit to local, and "g" bit to individual. */
124 	in6->s6_addr[8] &= ~EUI64_GBIT;	/* g bit to "individual" */
125 	in6->s6_addr[8] |= EUI64_UBIT;	/* u bit to "local" */
126 
127 	/* convert EUI64 into IPv6 interface identifier */
128 	EUI64_TO_IFID(in6);
129 
130 	return 0;
131 }
132 
133 static int
134 generate_tmp_ifid(seed0, seed1, ret)
135 	u_int8_t *seed0, *ret;
136 	const u_int8_t *seed1;
137 {
138 	MD5_CTX ctxt;
139 	u_int8_t seed[16], digest[16], nullbuf[8];
140 	u_int32_t val32;
141 
142 	/* If there's no hisotry, start with a random seed. */
143 	bzero(nullbuf, sizeof(nullbuf));
144 	if (bcmp(nullbuf, seed0, sizeof(nullbuf)) == 0) {
145 		int i;
146 
147 		for (i = 0; i < 2; i++) {
148 			val32 = arc4random();
149 			bcopy(&val32, seed + sizeof(val32) * i, sizeof(val32));
150 		}
151 	} else
152 		bcopy(seed0, seed, 8);
153 
154 	/* copy the right-most 64-bits of the given address */
155 	/* XXX assumption on the size of IFID */
156 	bcopy(seed1, &seed[8], 8);
157 
158 	if (0) {		/* for debugging purposes only */
159 		int i;
160 
161 		printf("generate_tmp_ifid: new randomized ID from: ");
162 		for (i = 0; i < 16; i++)
163 			printf("%02x", seed[i]);
164 		printf(" ");
165 	}
166 
167 	/* generate 16 bytes of pseudo-random value. */
168 	bzero(&ctxt, sizeof(ctxt));
169 	MD5Init(&ctxt);
170 	MD5Update(&ctxt, seed, sizeof(seed));
171 	MD5Final(digest, &ctxt);
172 
173 	/*
174 	 * RFC 3041 3.2.1. (3)
175 	 * Take the left-most 64-bits of the MD5 digest and set bit 6 (the
176 	 * left-most bit is numbered 0) to zero.
177 	 */
178 	bcopy(digest, ret, 8);
179 	ret[0] &= ~EUI64_UBIT;
180 
181 	/*
182 	 * XXX: we'd like to ensure that the generated value is not zero
183 	 * for simplicity.  If the caclculated digest happens to be zero,
184 	 * use a random non-zero value as the last resort.
185 	 */
186 	if (bcmp(nullbuf, ret, sizeof(nullbuf)) == 0) {
187 		nd6log((LOG_INFO,
188 		    "generate_tmp_ifid: computed MD5 value is zero.\n"));
189 
190 		val32 = arc4random();
191 		val32 = 1 + (val32 % (0xffffffff - 1));
192 	}
193 
194 	/*
195 	 * RFC 3041 3.2.1. (4)
196 	 * Take the rightmost 64-bits of the MD5 digest and save them in
197 	 * stable storage as the history value to be used in the next
198 	 * iteration of the algorithm.
199 	 */
200 	bcopy(&digest[8], seed0, 8);
201 
202 	if (0) {		/* for debugging purposes only */
203 		int i;
204 
205 		printf("to: ");
206 		for (i = 0; i < 16; i++)
207 			printf("%02x", digest[i]);
208 		printf("\n");
209 	}
210 
211 	return 0;
212 }
213 
214 /*
215  * Get interface identifier for the specified interface.
216  * XXX assumes single sockaddr_dl (AF_LINK address) per an interface
217  */
218 int
219 in6_get_hw_ifid(ifp, in6)
220 	struct ifnet *ifp;
221 	struct in6_addr *in6;	/* upper 64bits are preserved */
222 {
223 	struct ifaddr *ifa;
224 	struct sockaddr_dl *sdl;
225 	u_int8_t *addr;
226 	size_t addrlen;
227 	static u_int8_t allzero[8] = { 0, 0, 0, 0, 0, 0, 0, 0 };
228 	static u_int8_t allone[8] =
229 		{ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
230 
231 	for (ifa = ifp->if_addrlist.tqh_first;
232 	     ifa;
233 	     ifa = ifa->ifa_list.tqe_next) {
234 		if (ifa->ifa_addr->sa_family != AF_LINK)
235 			continue;
236 		sdl = (struct sockaddr_dl *)ifa->ifa_addr;
237 		if (sdl == NULL)
238 			continue;
239 		if (sdl->sdl_alen == 0)
240 			continue;
241 
242 		goto found;
243 	}
244 
245 	return -1;
246 
247 found:
248 	addr = LLADDR(sdl);
249 	addrlen = sdl->sdl_alen;
250 
251 	/* get EUI64 */
252 	switch (ifp->if_type) {
253 	case IFT_ETHER:
254 	case IFT_FDDI:
255 	case IFT_ISO88025:
256 	case IFT_ATM:
257 	case IFT_IEEE1394:
258 #ifdef IFT_IEEE80211
259 	case IFT_IEEE80211:
260 #endif
261 		/* IEEE802/EUI64 cases - what others? */
262 		/* IEEE1394 uses 16byte length address starting with EUI64 */
263 		if (addrlen > 8)
264 			addrlen = 8;
265 
266 		/* look at IEEE802/EUI64 only */
267 		if (addrlen != 8 && addrlen != 6)
268 			return -1;
269 
270 		/*
271 		 * check for invalid MAC address - on bsdi, we see it a lot
272 		 * since wildboar configures all-zero MAC on pccard before
273 		 * card insertion.
274 		 */
275 		if (bcmp(addr, allzero, addrlen) == 0)
276 			return -1;
277 		if (bcmp(addr, allone, addrlen) == 0)
278 			return -1;
279 
280 		/* make EUI64 address */
281 		if (addrlen == 8)
282 			bcopy(addr, &in6->s6_addr[8], 8);
283 		else if (addrlen == 6) {
284 			in6->s6_addr[8] = addr[0];
285 			in6->s6_addr[9] = addr[1];
286 			in6->s6_addr[10] = addr[2];
287 			in6->s6_addr[11] = 0xff;
288 			in6->s6_addr[12] = 0xfe;
289 			in6->s6_addr[13] = addr[3];
290 			in6->s6_addr[14] = addr[4];
291 			in6->s6_addr[15] = addr[5];
292 		}
293 		break;
294 
295 	case IFT_ARCNET:
296 		if (addrlen != 1)
297 			return -1;
298 		if (!addr[0])
299 			return -1;
300 
301 		bzero(&in6->s6_addr[8], 8);
302 		in6->s6_addr[15] = addr[0];
303 
304 		/*
305 		 * due to insufficient bitwidth, we mark it local.
306 		 */
307 		in6->s6_addr[8] &= ~EUI64_GBIT;	/* g bit to "individual" */
308 		in6->s6_addr[8] |= EUI64_UBIT;	/* u bit to "local" */
309 		break;
310 
311 	case IFT_GIF:
312 #ifdef IFT_STF
313 	case IFT_STF:
314 #endif
315 		/*
316 		 * RFC2893 says: "SHOULD use IPv4 address as ifid source".
317 		 * however, IPv4 address is not very suitable as unique
318 		 * identifier source (can be renumbered).
319 		 * we don't do this.
320 		 */
321 		return -1;
322 
323 	default:
324 		return -1;
325 	}
326 
327 	/* sanity check: g bit must not indicate "group" */
328 	if (EUI64_GROUP(in6))
329 		return -1;
330 
331 	/* convert EUI64 into IPv6 interface identifier */
332 	EUI64_TO_IFID(in6);
333 
334 	/*
335 	 * sanity check: ifid must not be all zero, avoid conflict with
336 	 * subnet router anycast
337 	 */
338 	if ((in6->s6_addr[8] & ~(EUI64_GBIT | EUI64_UBIT)) == 0x00 &&
339 	    bcmp(&in6->s6_addr[9], allzero, 7) == 0) {
340 		return -1;
341 	}
342 
343 	return 0;
344 }
345 
346 /*
347  * Get interface identifier for the specified interface.  If it is not
348  * available on ifp0, borrow interface identifier from other information
349  * sources.
350  */
351 static int
352 get_ifid(ifp0, altifp, in6)
353 	struct ifnet *ifp0;
354 	struct ifnet *altifp;	/* secondary EUI64 source */
355 	struct in6_addr *in6;
356 {
357 	struct ifnet *ifp;
358 
359 	/* first, try to get it from the interface itself */
360 	if (in6_get_hw_ifid(ifp0, in6) == 0) {
361 		nd6log((LOG_DEBUG, "%s: got interface identifier from itself\n",
362 		    if_name(ifp0)));
363 		goto success;
364 	}
365 
366 	/* try secondary EUI64 source. this basically is for ATM PVC */
367 	if (altifp && in6_get_hw_ifid(altifp, in6) == 0) {
368 		nd6log((LOG_DEBUG, "%s: got interface identifier from %s\n",
369 		    if_name(ifp0), if_name(altifp)));
370 		goto success;
371 	}
372 
373 	/* next, try to get it from some other hardware interface */
374 	IFNET_RLOCK();
375 	for (ifp = ifnet.tqh_first; ifp; ifp = ifp->if_list.tqe_next) {
376 		if (ifp == ifp0)
377 			continue;
378 		if (in6_get_hw_ifid(ifp, in6) != 0)
379 			continue;
380 
381 		/*
382 		 * to borrow ifid from other interface, ifid needs to be
383 		 * globally unique
384 		 */
385 		if (IFID_UNIVERSAL(in6)) {
386 			nd6log((LOG_DEBUG,
387 			    "%s: borrow interface identifier from %s\n",
388 			    if_name(ifp0), if_name(ifp)));
389 			IFNET_RUNLOCK();
390 			goto success;
391 		}
392 	}
393 	IFNET_RUNLOCK();
394 
395 	/* last resort: get from random number source */
396 	if (get_rand_ifid(ifp, in6) == 0) {
397 		nd6log((LOG_DEBUG,
398 		    "%s: interface identifier generated by random number\n",
399 		    if_name(ifp0)));
400 		goto success;
401 	}
402 
403 	printf("%s: failed to get interface identifier\n", if_name(ifp0));
404 	return -1;
405 
406 success:
407 	nd6log((LOG_INFO, "%s: ifid: %02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x\n",
408 	    if_name(ifp0), in6->s6_addr[8], in6->s6_addr[9], in6->s6_addr[10],
409 	    in6->s6_addr[11], in6->s6_addr[12], in6->s6_addr[13],
410 	    in6->s6_addr[14], in6->s6_addr[15]));
411 	return 0;
412 }
413 
414 static int
415 in6_ifattach_linklocal(ifp, altifp)
416 	struct ifnet *ifp;
417 	struct ifnet *altifp;	/* secondary EUI64 source */
418 {
419 	struct in6_ifaddr *ia;
420 	struct in6_aliasreq ifra;
421 	struct nd_prefixctl pr0;
422 	int i, error;
423 
424 	/*
425 	 * configure link-local address.
426 	 */
427 	bzero(&ifra, sizeof(ifra));
428 
429 	/*
430 	 * in6_update_ifa() does not use ifra_name, but we accurately set it
431 	 * for safety.
432 	 */
433 	strncpy(ifra.ifra_name, if_name(ifp), sizeof(ifra.ifra_name));
434 
435 	ifra.ifra_addr.sin6_family = AF_INET6;
436 	ifra.ifra_addr.sin6_len = sizeof(struct sockaddr_in6);
437 	ifra.ifra_addr.sin6_addr.s6_addr32[0] = htonl(0xfe800000);
438 	ifra.ifra_addr.sin6_addr.s6_addr32[1] = 0;
439 	if ((ifp->if_flags & IFF_LOOPBACK) != 0) {
440 		ifra.ifra_addr.sin6_addr.s6_addr32[2] = 0;
441 		ifra.ifra_addr.sin6_addr.s6_addr32[3] = htonl(1);
442 	} else {
443 		if (get_ifid(ifp, altifp, &ifra.ifra_addr.sin6_addr) != 0) {
444 			nd6log((LOG_ERR,
445 			    "%s: no ifid available\n", if_name(ifp)));
446 			return (-1);
447 		}
448 	}
449 	if (in6_setscope(&ifra.ifra_addr.sin6_addr, ifp, NULL))
450 		return (-1);
451 
452 	ifra.ifra_prefixmask.sin6_len = sizeof(struct sockaddr_in6);
453 	ifra.ifra_prefixmask.sin6_family = AF_INET6;
454 	ifra.ifra_prefixmask.sin6_addr = in6mask64;
455 	/* link-local addresses should NEVER expire. */
456 	ifra.ifra_lifetime.ia6t_vltime = ND6_INFINITE_LIFETIME;
457 	ifra.ifra_lifetime.ia6t_pltime = ND6_INFINITE_LIFETIME;
458 
459 	/*
460 	 * Now call in6_update_ifa() to do a bunch of procedures to configure
461 	 * a link-local address. We can set the 3rd argument to NULL, because
462 	 * we know there's no other link-local address on the interface
463 	 * and therefore we are adding one (instead of updating one).
464 	 */
465 	if ((error = in6_update_ifa(ifp, &ifra, NULL,
466 				    IN6_IFAUPDATE_DADDELAY)) != 0) {
467 		/*
468 		 * XXX: When the interface does not support IPv6, this call
469 		 * would fail in the SIOCSIFADDR ioctl.  I believe the
470 		 * notification is rather confusing in this case, so just
471 		 * suppress it.  (jinmei@kame.net 20010130)
472 		 */
473 		if (error != EAFNOSUPPORT)
474 			nd6log((LOG_NOTICE, "in6_ifattach_linklocal: failed to "
475 			    "configure a link-local address on %s "
476 			    "(errno=%d)\n",
477 			    if_name(ifp), error));
478 		return (-1);
479 	}
480 
481 	ia = in6ifa_ifpforlinklocal(ifp, 0); /* ia must not be NULL */
482 #ifdef DIAGNOSTIC
483 	if (!ia) {
484 		panic("ia == NULL in in6_ifattach_linklocal");
485 		/* NOTREACHED */
486 	}
487 #endif
488 
489 	/*
490 	 * Make the link-local prefix (fe80::%link/64) as on-link.
491 	 * Since we'd like to manage prefixes separately from addresses,
492 	 * we make an ND6 prefix structure for the link-local prefix,
493 	 * and add it to the prefix list as a never-expire prefix.
494 	 * XXX: this change might affect some existing code base...
495 	 */
496 	bzero(&pr0, sizeof(pr0));
497 	pr0.ndpr_ifp = ifp;
498 	/* this should be 64 at this moment. */
499 	pr0.ndpr_plen = in6_mask2len(&ifra.ifra_prefixmask.sin6_addr, NULL);
500 	pr0.ndpr_prefix = ifra.ifra_addr;
501 	/* apply the mask for safety. (nd6_prelist_add will apply it again) */
502 	for (i = 0; i < 4; i++) {
503 		pr0.ndpr_prefix.sin6_addr.s6_addr32[i] &=
504 		    in6mask64.s6_addr32[i];
505 	}
506 	/*
507 	 * Initialize parameters.  The link-local prefix must always be
508 	 * on-link, and its lifetimes never expire.
509 	 */
510 	pr0.ndpr_raf_onlink = 1;
511 	pr0.ndpr_raf_auto = 1;	/* probably meaningless */
512 	pr0.ndpr_vltime = ND6_INFINITE_LIFETIME;
513 	pr0.ndpr_pltime = ND6_INFINITE_LIFETIME;
514 	/*
515 	 * Since there is no other link-local addresses, nd6_prefix_lookup()
516 	 * probably returns NULL.  However, we cannot always expect the result.
517 	 * For example, if we first remove the (only) existing link-local
518 	 * address, and then reconfigure another one, the prefix is still
519 	 * valid with referring to the old link-local address.
520 	 */
521 	if (nd6_prefix_lookup(&pr0) == NULL) {
522 		if ((error = nd6_prelist_add(&pr0, NULL, NULL)) != 0)
523 			return (error);
524 	}
525 
526 	return 0;
527 }
528 
529 static int
530 in6_ifattach_loopback(ifp)
531 	struct ifnet *ifp;	/* must be IFT_LOOP */
532 {
533 	struct in6_aliasreq ifra;
534 	int error;
535 
536 	bzero(&ifra, sizeof(ifra));
537 
538 	/*
539 	 * in6_update_ifa() does not use ifra_name, but we accurately set it
540 	 * for safety.
541 	 */
542 	strncpy(ifra.ifra_name, if_name(ifp), sizeof(ifra.ifra_name));
543 
544 	ifra.ifra_prefixmask.sin6_len = sizeof(struct sockaddr_in6);
545 	ifra.ifra_prefixmask.sin6_family = AF_INET6;
546 	ifra.ifra_prefixmask.sin6_addr = in6mask128;
547 
548 	/*
549 	 * Always initialize ia_dstaddr (= broadcast address) to loopback
550 	 * address.  Follows IPv4 practice - see in_ifinit().
551 	 */
552 	ifra.ifra_dstaddr.sin6_len = sizeof(struct sockaddr_in6);
553 	ifra.ifra_dstaddr.sin6_family = AF_INET6;
554 	ifra.ifra_dstaddr.sin6_addr = in6addr_loopback;
555 
556 	ifra.ifra_addr.sin6_len = sizeof(struct sockaddr_in6);
557 	ifra.ifra_addr.sin6_family = AF_INET6;
558 	ifra.ifra_addr.sin6_addr = in6addr_loopback;
559 
560 	/* the loopback  address should NEVER expire. */
561 	ifra.ifra_lifetime.ia6t_vltime = ND6_INFINITE_LIFETIME;
562 	ifra.ifra_lifetime.ia6t_pltime = ND6_INFINITE_LIFETIME;
563 
564 	/* we don't need to perform DAD on loopback interfaces. */
565 	ifra.ifra_flags |= IN6_IFF_NODAD;
566 
567 	/* skip registration to the prefix list. XXX should be temporary. */
568 	ifra.ifra_flags |= IN6_IFF_NOPFX;
569 
570 	/*
571 	 * We are sure that this is a newly assigned address, so we can set
572 	 * NULL to the 3rd arg.
573 	 */
574 	if ((error = in6_update_ifa(ifp, &ifra, NULL, 0)) != 0) {
575 		nd6log((LOG_ERR, "in6_ifattach_loopback: failed to configure "
576 		    "the loopback address on %s (errno=%d)\n",
577 		    if_name(ifp), error));
578 		return (-1);
579 	}
580 
581 	return 0;
582 }
583 
584 /*
585  * compute NI group address, based on the current hostname setting.
586  * see draft-ietf-ipngwg-icmp-name-lookup-* (04 and later).
587  *
588  * when ifp == NULL, the caller is responsible for filling scopeid.
589  */
590 int
591 in6_nigroup(ifp, name, namelen, in6)
592 	struct ifnet *ifp;
593 	const char *name;
594 	int namelen;
595 	struct in6_addr *in6;
596 {
597 	const char *p;
598 	u_char *q;
599 	MD5_CTX ctxt;
600 	u_int8_t digest[16];
601 	char l;
602 	char n[64];	/* a single label must not exceed 63 chars */
603 
604 	if (!namelen || !name)
605 		return -1;
606 
607 	p = name;
608 	while (p && *p && *p != '.' && p - name < namelen)
609 		p++;
610 	if (p - name > sizeof(n) - 1)
611 		return -1;	/* label too long */
612 	l = p - name;
613 	strncpy(n, name, l);
614 	n[(int)l] = '\0';
615 	for (q = n; *q; q++) {
616 		if ('A' <= *q && *q <= 'Z')
617 			*q = *q - 'A' + 'a';
618 	}
619 
620 	/* generate 8 bytes of pseudo-random value. */
621 	bzero(&ctxt, sizeof(ctxt));
622 	MD5Init(&ctxt);
623 	MD5Update(&ctxt, &l, sizeof(l));
624 	MD5Update(&ctxt, n, l);
625 	MD5Final(digest, &ctxt);
626 
627 	bzero(in6, sizeof(*in6));
628 	in6->s6_addr16[0] = IPV6_ADDR_INT16_MLL;
629 	in6->s6_addr8[11] = 2;
630 	bcopy(digest, &in6->s6_addr32[3], sizeof(in6->s6_addr32[3]));
631 	if (in6_setscope(in6, ifp, NULL))
632 		return (-1); /* XXX: should not fail */
633 
634 	return 0;
635 }
636 
637 /*
638  * XXX multiple loopback interface needs more care.  for instance,
639  * nodelocal address needs to be configured onto only one of them.
640  * XXX multiple link-local address case
641  */
642 void
643 in6_ifattach(ifp, altifp)
644 	struct ifnet *ifp;
645 	struct ifnet *altifp;	/* secondary EUI64 source */
646 {
647 	struct in6_ifaddr *ia;
648 	struct in6_addr in6;
649 
650 	/* some of the interfaces are inherently not IPv6 capable */
651 	switch (ifp->if_type) {
652 	case IFT_PFLOG:
653 	case IFT_PFSYNC:
654 	case IFT_CARP:
655 		return;
656 	}
657 
658 	/*
659 	 * quirks based on interface type
660 	 */
661 	switch (ifp->if_type) {
662 #ifdef IFT_STF
663 	case IFT_STF:
664 		/*
665 		 * 6to4 interface is a very special kind of beast.
666 		 * no multicast, no linklocal.  RFC2529 specifies how to make
667 		 * linklocals for 6to4 interface, but there's no use and
668 		 * it is rather harmful to have one.
669 		 */
670 		goto statinit;
671 #endif
672 	default:
673 		break;
674 	}
675 
676 	/*
677 	 * usually, we require multicast capability to the interface
678 	 */
679 	if ((ifp->if_flags & IFF_MULTICAST) == 0) {
680 		nd6log((LOG_INFO, "in6_ifattach: "
681 		    "%s is not multicast capable, IPv6 not enabled\n",
682 		    if_name(ifp)));
683 		return;
684 	}
685 
686 	/*
687 	 * assign loopback address for loopback interface.
688 	 * XXX multiple loopback interface case.
689 	 */
690 	if ((ifp->if_flags & IFF_LOOPBACK) != 0) {
691 		in6 = in6addr_loopback;
692 		if (in6ifa_ifpwithaddr(ifp, &in6) == NULL) {
693 			if (in6_ifattach_loopback(ifp) != 0)
694 				return;
695 		}
696 	}
697 
698 	/*
699 	 * assign a link-local address, if there's none.
700 	 */
701 	if (ip6_auto_linklocal && ifp->if_type != IFT_BRIDGE) {
702 		ia = in6ifa_ifpforlinklocal(ifp, 0);
703 		if (ia == NULL) {
704 			if (in6_ifattach_linklocal(ifp, altifp) == 0) {
705 				/* linklocal address assigned */
706 			} else {
707 				/* failed to assign linklocal address. bark? */
708 			}
709 		}
710 	}
711 
712 #ifdef IFT_STF			/* XXX */
713 statinit:
714 #endif
715 
716 	/* update dynamically. */
717 	if (in6_maxmtu < ifp->if_mtu)
718 		in6_maxmtu = ifp->if_mtu;
719 }
720 
721 /*
722  * NOTE: in6_ifdetach() does not support loopback if at this moment.
723  * We don't need this function in bsdi, because interfaces are never removed
724  * from the ifnet list in bsdi.
725  */
726 void
727 in6_ifdetach(ifp)
728 	struct ifnet *ifp;
729 {
730 	struct in6_ifaddr *ia, *oia;
731 	struct ifaddr *ifa, *next;
732 	struct rtentry *rt;
733 	short rtflags;
734 	struct sockaddr_in6 sin6;
735 	struct in6_multi_mship *imm;
736 
737 	/* remove neighbor management table */
738 	nd6_purge(ifp);
739 
740 	/* nuke any of IPv6 addresses we have */
741 	for (ifa = ifp->if_addrlist.tqh_first; ifa; ifa = next) {
742 		next = ifa->ifa_list.tqe_next;
743 		if (ifa->ifa_addr->sa_family != AF_INET6)
744 			continue;
745 		in6_purgeaddr(ifa);
746 	}
747 
748 	/* undo everything done by in6_ifattach(), just in case */
749 	for (ifa = ifp->if_addrlist.tqh_first; ifa; ifa = next) {
750 		next = ifa->ifa_list.tqe_next;
751 
752 		if (ifa->ifa_addr->sa_family != AF_INET6
753 		 || !IN6_IS_ADDR_LINKLOCAL(&satosin6(&ifa->ifa_addr)->sin6_addr)) {
754 			continue;
755 		}
756 
757 		ia = (struct in6_ifaddr *)ifa;
758 
759 		/*
760 		 * leave from multicast groups we have joined for the interface
761 		 */
762 		while ((imm = ia->ia6_memberships.lh_first) != NULL) {
763 			LIST_REMOVE(imm, i6mm_chain);
764 			in6_leavegroup(imm);
765 		}
766 
767 		/* remove from the routing table */
768 		if ((ia->ia_flags & IFA_ROUTE) &&
769 		    (rt = rtalloc1((struct sockaddr *)&ia->ia_addr, 0, 0UL))) {
770 			rtflags = rt->rt_flags;
771 			rtfree(rt);
772 			rtrequest(RTM_DELETE, (struct sockaddr *)&ia->ia_addr,
773 			    (struct sockaddr *)&ia->ia_addr,
774 			    (struct sockaddr *)&ia->ia_prefixmask,
775 			    rtflags, (struct rtentry **)0);
776 		}
777 
778 		/* remove from the linked list */
779 		TAILQ_REMOVE(&ifp->if_addrlist, (struct ifaddr *)ia, ifa_list);
780 		IFAFREE(&ia->ia_ifa);
781 
782 		/* also remove from the IPv6 address chain(itojun&jinmei) */
783 		oia = ia;
784 		if (oia == (ia = in6_ifaddr))
785 			in6_ifaddr = ia->ia_next;
786 		else {
787 			while (ia->ia_next && (ia->ia_next != oia))
788 				ia = ia->ia_next;
789 			if (ia->ia_next)
790 				ia->ia_next = oia->ia_next;
791 			else {
792 				nd6log((LOG_ERR,
793 				    "%s: didn't unlink in6ifaddr from list\n",
794 				    if_name(ifp)));
795 			}
796 		}
797 
798 		IFAFREE(&oia->ia_ifa);
799 	}
800 
801 	in6_pcbpurgeif0(&udbinfo, ifp);
802 	in6_pcbpurgeif0(&ripcbinfo, ifp);
803 	/* leave from all multicast groups joined */
804 	in6_purgemaddrs(ifp);
805 
806 	/*
807 	 * remove neighbor management table.  we call it twice just to make
808 	 * sure we nuke everything.  maybe we need just one call.
809 	 * XXX: since the first call did not release addresses, some prefixes
810 	 * might remain.  We should call nd6_purge() again to release the
811 	 * prefixes after removing all addresses above.
812 	 * (Or can we just delay calling nd6_purge until at this point?)
813 	 */
814 	nd6_purge(ifp);
815 
816 	/* remove route to link-local allnodes multicast (ff02::1) */
817 	bzero(&sin6, sizeof(sin6));
818 	sin6.sin6_len = sizeof(struct sockaddr_in6);
819 	sin6.sin6_family = AF_INET6;
820 	sin6.sin6_addr = in6addr_linklocal_allnodes;
821 	if (in6_setscope(&sin6.sin6_addr, ifp, NULL))
822 		/* XXX: should not fail */
823 		return;
824 	/* XXX grab lock first to avoid LOR */
825 	if (rt_tables[AF_INET6] != NULL) {
826 		RADIX_NODE_HEAD_LOCK(rt_tables[AF_INET6]);
827 		rt = rtalloc1((struct sockaddr *)&sin6, 0, 0UL);
828 		if (rt) {
829 			if (rt->rt_ifp == ifp)
830 				rtexpunge(rt);
831 			RTFREE_LOCKED(rt);
832 		}
833 		RADIX_NODE_HEAD_UNLOCK(rt_tables[AF_INET6]);
834 	}
835 }
836 
837 int
838 in6_get_tmpifid(ifp, retbuf, baseid, generate)
839 	struct ifnet *ifp;
840 	u_int8_t *retbuf;
841 	const u_int8_t *baseid;
842 	int generate;
843 {
844 	u_int8_t nullbuf[8];
845 	struct nd_ifinfo *ndi = ND_IFINFO(ifp);
846 
847 	bzero(nullbuf, sizeof(nullbuf));
848 	if (bcmp(ndi->randomid, nullbuf, sizeof(nullbuf)) == 0) {
849 		/* we've never created a random ID.  Create a new one. */
850 		generate = 1;
851 	}
852 
853 	if (generate) {
854 		bcopy(baseid, ndi->randomseed1, sizeof(ndi->randomseed1));
855 
856 		/* generate_tmp_ifid will update seedn and buf */
857 		(void)generate_tmp_ifid(ndi->randomseed0, ndi->randomseed1,
858 		    ndi->randomid);
859 	}
860 	bcopy(ndi->randomid, retbuf, 8);
861 
862 	return (0);
863 }
864 
865 void
866 in6_tmpaddrtimer(ignored_arg)
867 	void *ignored_arg;
868 {
869 	struct nd_ifinfo *ndi;
870 	u_int8_t nullbuf[8];
871 	struct ifnet *ifp;
872 	int s = splnet();
873 
874 	callout_reset(&in6_tmpaddrtimer_ch,
875 	    (ip6_temp_preferred_lifetime - ip6_desync_factor -
876 	    ip6_temp_regen_advance) * hz, in6_tmpaddrtimer, NULL);
877 
878 	bzero(nullbuf, sizeof(nullbuf));
879 	for (ifp = TAILQ_FIRST(&ifnet); ifp; ifp = TAILQ_NEXT(ifp, if_list)) {
880 		ndi = ND_IFINFO(ifp);
881 		if (bcmp(ndi->randomid, nullbuf, sizeof(nullbuf)) != 0) {
882 			/*
883 			 * We've been generating a random ID on this interface.
884 			 * Create a new one.
885 			 */
886 			(void)generate_tmp_ifid(ndi->randomseed0,
887 			    ndi->randomseed1, ndi->randomid);
888 		}
889 	}
890 
891 	splx(s);
892 }
893 
894 static void
895 in6_purgemaddrs(ifp)
896 	struct ifnet *ifp;
897 {
898 	struct in6_multi *in6m;
899 	struct in6_multi *oin6m;
900 
901 #ifdef DIAGNOSTIC
902 	printf("%s: purging ifp %p\n", __func__, ifp);
903 #endif
904 
905 	IFF_LOCKGIANT(ifp);
906 	LIST_FOREACH_SAFE(in6m, &in6_multihead, in6m_entry, oin6m) {
907 		if (in6m->in6m_ifp == ifp)
908 			in6_delmulti(in6m);
909 	}
910 	IFF_UNLOCKGIANT(ifp);
911 }
912