xref: /freebsd/sys/netinet6/in6_ifattach.c (revision d056fa046c6a91b90cd98165face0e42a33a5173)
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 #include <net/net_osdep.h>
62 
63 unsigned long in6_maxmtu = 0;
64 
65 #ifdef IP6_AUTO_LINKLOCAL
66 int ip6_auto_linklocal = IP6_AUTO_LINKLOCAL;
67 #else
68 int ip6_auto_linklocal = 1;	/* enable by default */
69 #endif
70 
71 struct callout in6_tmpaddrtimer_ch;
72 
73 extern struct inpcbinfo udbinfo;
74 extern struct inpcbinfo ripcbinfo;
75 
76 static int get_rand_ifid __P((struct ifnet *, struct in6_addr *));
77 static int generate_tmp_ifid __P((u_int8_t *, const u_int8_t *, u_int8_t *));
78 static int get_ifid __P((struct ifnet *, struct ifnet *, struct in6_addr *));
79 static int in6_ifattach_linklocal __P((struct ifnet *, struct ifnet *));
80 static int in6_ifattach_loopback __P((struct ifnet *));
81 
82 #define EUI64_GBIT	0x01
83 #define EUI64_UBIT	0x02
84 #define EUI64_TO_IFID(in6)	do {(in6)->s6_addr[8] ^= EUI64_UBIT; } while (0)
85 #define EUI64_GROUP(in6)	((in6)->s6_addr[8] & EUI64_GBIT)
86 #define EUI64_INDIVIDUAL(in6)	(!EUI64_GROUP(in6))
87 #define EUI64_LOCAL(in6)	((in6)->s6_addr[8] & EUI64_UBIT)
88 #define EUI64_UNIVERSAL(in6)	(!EUI64_LOCAL(in6))
89 
90 #define IFID_LOCAL(in6)		(!EUI64_LOCAL(in6))
91 #define IFID_UNIVERSAL(in6)	(!EUI64_UNIVERSAL(in6))
92 
93 /*
94  * Generate a last-resort interface identifier, when the machine has no
95  * IEEE802/EUI64 address sources.
96  * The goal here is to get an interface identifier that is
97  * (1) random enough and (2) does not change across reboot.
98  * We currently use MD5(hostname) for it.
99  */
100 static int
101 get_rand_ifid(ifp, in6)
102 	struct ifnet *ifp;
103 	struct in6_addr *in6;	/* upper 64bits are preserved */
104 {
105 	MD5_CTX ctxt;
106 	u_int8_t digest[16];
107 	int hostnamelen	= strlen(hostname);
108 
109 #if 0
110 	/* we need at least several letters as seed for ifid */
111 	if (hostnamelen < 3)
112 		return -1;
113 #endif
114 
115 	/* generate 8 bytes of pseudo-random value. */
116 	bzero(&ctxt, sizeof(ctxt));
117 	MD5Init(&ctxt);
118 	MD5Update(&ctxt, hostname, hostnamelen);
119 	MD5Final(digest, &ctxt);
120 
121 	/* assumes sizeof(digest) > sizeof(ifid) */
122 	bcopy(digest, &in6->s6_addr[8], 8);
123 
124 	/* make sure to set "u" bit to local, and "g" bit to individual. */
125 	in6->s6_addr[8] &= ~EUI64_GBIT;	/* g bit to "individual" */
126 	in6->s6_addr[8] |= EUI64_UBIT;	/* u bit to "local" */
127 
128 	/* convert EUI64 into IPv6 interface identifier */
129 	EUI64_TO_IFID(in6);
130 
131 	return 0;
132 }
133 
134 static int
135 generate_tmp_ifid(seed0, seed1, ret)
136 	u_int8_t *seed0, *ret;
137 	const u_int8_t *seed1;
138 {
139 	MD5_CTX ctxt;
140 	u_int8_t seed[16], digest[16], nullbuf[8];
141 	u_int32_t val32;
142 
143 	/* If there's no hisotry, start with a random seed. */
144 	bzero(nullbuf, sizeof(nullbuf));
145 	if (bcmp(nullbuf, seed0, sizeof(nullbuf)) == 0) {
146 		int i;
147 
148 		for (i = 0; i < 2; i++) {
149 			val32 = arc4random();
150 			bcopy(&val32, seed + sizeof(val32) * i, sizeof(val32));
151 		}
152 	} else
153 		bcopy(seed0, seed, 8);
154 
155 	/* copy the right-most 64-bits of the given address */
156 	/* XXX assumption on the size of IFID */
157 	bcopy(seed1, &seed[8], 8);
158 
159 	if (0) {		/* for debugging purposes only */
160 		int i;
161 
162 		printf("generate_tmp_ifid: new randomized ID from: ");
163 		for (i = 0; i < 16; i++)
164 			printf("%02x", seed[i]);
165 		printf(" ");
166 	}
167 
168 	/* generate 16 bytes of pseudo-random value. */
169 	bzero(&ctxt, sizeof(ctxt));
170 	MD5Init(&ctxt);
171 	MD5Update(&ctxt, seed, sizeof(seed));
172 	MD5Final(digest, &ctxt);
173 
174 	/*
175 	 * RFC 3041 3.2.1. (3)
176 	 * Take the left-most 64-bits of the MD5 digest and set bit 6 (the
177 	 * left-most bit is numbered 0) to zero.
178 	 */
179 	bcopy(digest, ret, 8);
180 	ret[0] &= ~EUI64_UBIT;
181 
182 	/*
183 	 * XXX: we'd like to ensure that the generated value is not zero
184 	 * for simplicity.  If the caclculated digest happens to be zero,
185 	 * use a random non-zero value as the last resort.
186 	 */
187 	if (bcmp(nullbuf, ret, sizeof(nullbuf)) == 0) {
188 		nd6log((LOG_INFO,
189 		    "generate_tmp_ifid: computed MD5 value is zero.\n"));
190 
191 		val32 = arc4random();
192 		val32 = 1 + (val32 % (0xffffffff - 1));
193 	}
194 
195 	/*
196 	 * RFC 3041 3.2.1. (4)
197 	 * Take the rightmost 64-bits of the MD5 digest and save them in
198 	 * stable storage as the history value to be used in the next
199 	 * iteration of the algorithm.
200 	 */
201 	bcopy(&digest[8], seed0, 8);
202 
203 	if (0) {		/* for debugging purposes only */
204 		int i;
205 
206 		printf("to: ");
207 		for (i = 0; i < 16; i++)
208 			printf("%02x", digest[i]);
209 		printf("\n");
210 	}
211 
212 	return 0;
213 }
214 
215 /*
216  * Get interface identifier for the specified interface.
217  * XXX assumes single sockaddr_dl (AF_LINK address) per an interface
218  */
219 int
220 in6_get_hw_ifid(ifp, in6)
221 	struct ifnet *ifp;
222 	struct in6_addr *in6;	/* upper 64bits are preserved */
223 {
224 	struct ifaddr *ifa;
225 	struct sockaddr_dl *sdl;
226 	u_int8_t *addr;
227 	size_t addrlen;
228 	static u_int8_t allzero[8] = { 0, 0, 0, 0, 0, 0, 0, 0 };
229 	static u_int8_t allone[8] =
230 		{ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
231 
232 	for (ifa = ifp->if_addrlist.tqh_first;
233 	     ifa;
234 	     ifa = ifa->ifa_list.tqe_next) {
235 		if (ifa->ifa_addr->sa_family != AF_LINK)
236 			continue;
237 		sdl = (struct sockaddr_dl *)ifa->ifa_addr;
238 		if (sdl == NULL)
239 			continue;
240 		if (sdl->sdl_alen == 0)
241 			continue;
242 
243 		goto found;
244 	}
245 
246 	return -1;
247 
248 found:
249 	addr = LLADDR(sdl);
250 	addrlen = sdl->sdl_alen;
251 
252 	/* get EUI64 */
253 	switch (ifp->if_type) {
254 	case IFT_ETHER:
255 	case IFT_FDDI:
256 	case IFT_ISO88025:
257 	case IFT_ATM:
258 	case IFT_IEEE1394:
259 #ifdef IFT_IEEE80211
260 	case IFT_IEEE80211:
261 #endif
262 		/* IEEE802/EUI64 cases - what others? */
263 		/* IEEE1394 uses 16byte length address starting with EUI64 */
264 		if (addrlen > 8)
265 			addrlen = 8;
266 
267 		/* look at IEEE802/EUI64 only */
268 		if (addrlen != 8 && addrlen != 6)
269 			return -1;
270 
271 		/*
272 		 * check for invalid MAC address - on bsdi, we see it a lot
273 		 * since wildboar configures all-zero MAC on pccard before
274 		 * card insertion.
275 		 */
276 		if (bcmp(addr, allzero, addrlen) == 0)
277 			return -1;
278 		if (bcmp(addr, allone, addrlen) == 0)
279 			return -1;
280 
281 		/* make EUI64 address */
282 		if (addrlen == 8)
283 			bcopy(addr, &in6->s6_addr[8], 8);
284 		else if (addrlen == 6) {
285 			in6->s6_addr[8] = addr[0];
286 			in6->s6_addr[9] = addr[1];
287 			in6->s6_addr[10] = addr[2];
288 			in6->s6_addr[11] = 0xff;
289 			in6->s6_addr[12] = 0xfe;
290 			in6->s6_addr[13] = addr[3];
291 			in6->s6_addr[14] = addr[4];
292 			in6->s6_addr[15] = addr[5];
293 		}
294 		break;
295 
296 	case IFT_ARCNET:
297 		if (addrlen != 1)
298 			return -1;
299 		if (!addr[0])
300 			return -1;
301 
302 		bzero(&in6->s6_addr[8], 8);
303 		in6->s6_addr[15] = addr[0];
304 
305 		/*
306 		 * due to insufficient bitwidth, we mark it local.
307 		 */
308 		in6->s6_addr[8] &= ~EUI64_GBIT;	/* g bit to "individual" */
309 		in6->s6_addr[8] |= EUI64_UBIT;	/* u bit to "local" */
310 		break;
311 
312 	case IFT_GIF:
313 #ifdef IFT_STF
314 	case IFT_STF:
315 #endif
316 		/*
317 		 * RFC2893 says: "SHOULD use IPv4 address as ifid source".
318 		 * however, IPv4 address is not very suitable as unique
319 		 * identifier source (can be renumbered).
320 		 * we don't do this.
321 		 */
322 		return -1;
323 
324 	default:
325 		return -1;
326 	}
327 
328 	/* sanity check: g bit must not indicate "group" */
329 	if (EUI64_GROUP(in6))
330 		return -1;
331 
332 	/* convert EUI64 into IPv6 interface identifier */
333 	EUI64_TO_IFID(in6);
334 
335 	/*
336 	 * sanity check: ifid must not be all zero, avoid conflict with
337 	 * subnet router anycast
338 	 */
339 	if ((in6->s6_addr[8] & ~(EUI64_GBIT | EUI64_UBIT)) == 0x00 &&
340 	    bcmp(&in6->s6_addr[9], allzero, 7) == 0) {
341 		return -1;
342 	}
343 
344 	return 0;
345 }
346 
347 /*
348  * Get interface identifier for the specified interface.  If it is not
349  * available on ifp0, borrow interface identifier from other information
350  * sources.
351  */
352 static int
353 get_ifid(ifp0, altifp, in6)
354 	struct ifnet *ifp0;
355 	struct ifnet *altifp;	/* secondary EUI64 source */
356 	struct in6_addr *in6;
357 {
358 	struct ifnet *ifp;
359 
360 	/* first, try to get it from the interface itself */
361 	if (in6_get_hw_ifid(ifp0, in6) == 0) {
362 		nd6log((LOG_DEBUG, "%s: got interface identifier from itself\n",
363 		    if_name(ifp0)));
364 		goto success;
365 	}
366 
367 	/* try secondary EUI64 source. this basically is for ATM PVC */
368 	if (altifp && in6_get_hw_ifid(altifp, in6) == 0) {
369 		nd6log((LOG_DEBUG, "%s: got interface identifier from %s\n",
370 		    if_name(ifp0), if_name(altifp)));
371 		goto success;
372 	}
373 
374 	/* next, try to get it from some other hardware interface */
375 	IFNET_RLOCK();
376 	for (ifp = ifnet.tqh_first; ifp; ifp = ifp->if_list.tqe_next) {
377 		if (ifp == ifp0)
378 			continue;
379 		if (in6_get_hw_ifid(ifp, in6) != 0)
380 			continue;
381 
382 		/*
383 		 * to borrow ifid from other interface, ifid needs to be
384 		 * globally unique
385 		 */
386 		if (IFID_UNIVERSAL(in6)) {
387 			nd6log((LOG_DEBUG,
388 			    "%s: borrow interface identifier from %s\n",
389 			    if_name(ifp0), if_name(ifp)));
390 			IFNET_RUNLOCK();
391 			goto success;
392 		}
393 	}
394 	IFNET_RUNLOCK();
395 
396 	/* last resort: get from random number source */
397 	if (get_rand_ifid(ifp, in6) == 0) {
398 		nd6log((LOG_DEBUG,
399 		    "%s: interface identifier generated by random number\n",
400 		    if_name(ifp0)));
401 		goto success;
402 	}
403 
404 	printf("%s: failed to get interface identifier\n", if_name(ifp0));
405 	return -1;
406 
407 success:
408 	nd6log((LOG_INFO, "%s: ifid: %02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x\n",
409 	    if_name(ifp0), in6->s6_addr[8], in6->s6_addr[9], in6->s6_addr[10],
410 	    in6->s6_addr[11], in6->s6_addr[12], in6->s6_addr[13],
411 	    in6->s6_addr[14], in6->s6_addr[15]));
412 	return 0;
413 }
414 
415 static int
416 in6_ifattach_linklocal(ifp, altifp)
417 	struct ifnet *ifp;
418 	struct ifnet *altifp;	/* secondary EUI64 source */
419 {
420 	struct in6_ifaddr *ia;
421 	struct in6_aliasreq ifra;
422 	struct nd_prefixctl pr0;
423 	int i, error;
424 
425 	/*
426 	 * configure link-local address.
427 	 */
428 	bzero(&ifra, sizeof(ifra));
429 
430 	/*
431 	 * in6_update_ifa() does not use ifra_name, but we accurately set it
432 	 * for safety.
433 	 */
434 	strncpy(ifra.ifra_name, if_name(ifp), sizeof(ifra.ifra_name));
435 
436 	ifra.ifra_addr.sin6_family = AF_INET6;
437 	ifra.ifra_addr.sin6_len = sizeof(struct sockaddr_in6);
438 	ifra.ifra_addr.sin6_addr.s6_addr32[0] = htonl(0xfe800000);
439 	ifra.ifra_addr.sin6_addr.s6_addr32[1] = 0;
440 	if ((ifp->if_flags & IFF_LOOPBACK) != 0) {
441 		ifra.ifra_addr.sin6_addr.s6_addr32[2] = 0;
442 		ifra.ifra_addr.sin6_addr.s6_addr32[3] = htonl(1);
443 	} else {
444 		if (get_ifid(ifp, altifp, &ifra.ifra_addr.sin6_addr) != 0) {
445 			nd6log((LOG_ERR,
446 			    "%s: no ifid available\n", if_name(ifp)));
447 			return (-1);
448 		}
449 	}
450 	if (in6_setscope(&ifra.ifra_addr.sin6_addr, ifp, NULL))
451 		return (-1);
452 
453 	ifra.ifra_prefixmask.sin6_len = sizeof(struct sockaddr_in6);
454 	ifra.ifra_prefixmask.sin6_family = AF_INET6;
455 	ifra.ifra_prefixmask.sin6_addr = in6mask64;
456 	/* link-local addresses should NEVER expire. */
457 	ifra.ifra_lifetime.ia6t_vltime = ND6_INFINITE_LIFETIME;
458 	ifra.ifra_lifetime.ia6t_pltime = ND6_INFINITE_LIFETIME;
459 
460 	/*
461 	 * Now call in6_update_ifa() to do a bunch of procedures to configure
462 	 * a link-local address. We can set the 3rd argument to NULL, because
463 	 * we know there's no other link-local address on the interface
464 	 * and therefore we are adding one (instead of updating one).
465 	 */
466 	if ((error = in6_update_ifa(ifp, &ifra, NULL,
467 				    IN6_IFAUPDATE_DADDELAY)) != 0) {
468 		/*
469 		 * XXX: When the interface does not support IPv6, this call
470 		 * would fail in the SIOCSIFADDR ioctl.  I believe the
471 		 * notification is rather confusing in this case, so just
472 		 * suppress it.  (jinmei@kame.net 20010130)
473 		 */
474 		if (error != EAFNOSUPPORT)
475 			nd6log((LOG_NOTICE, "in6_ifattach_linklocal: failed to "
476 			    "configure a link-local address on %s "
477 			    "(errno=%d)\n",
478 			    if_name(ifp), error));
479 		return (-1);
480 	}
481 
482 	ia = in6ifa_ifpforlinklocal(ifp, 0); /* ia must not be NULL */
483 #ifdef DIAGNOSTIC
484 	if (!ia) {
485 		panic("ia == NULL in in6_ifattach_linklocal");
486 		/* NOTREACHED */
487 	}
488 #endif
489 
490 	/*
491 	 * Make the link-local prefix (fe80::%link/64) as on-link.
492 	 * Since we'd like to manage prefixes separately from addresses,
493 	 * we make an ND6 prefix structure for the link-local prefix,
494 	 * and add it to the prefix list as a never-expire prefix.
495 	 * XXX: this change might affect some existing code base...
496 	 */
497 	bzero(&pr0, sizeof(pr0));
498 	pr0.ndpr_ifp = ifp;
499 	/* this should be 64 at this moment. */
500 	pr0.ndpr_plen = in6_mask2len(&ifra.ifra_prefixmask.sin6_addr, NULL);
501 	pr0.ndpr_prefix = ifra.ifra_addr;
502 	/* apply the mask for safety. (nd6_prelist_add will apply it again) */
503 	for (i = 0; i < 4; i++) {
504 		pr0.ndpr_prefix.sin6_addr.s6_addr32[i] &=
505 		    in6mask64.s6_addr32[i];
506 	}
507 	/*
508 	 * Initialize parameters.  The link-local prefix must always be
509 	 * on-link, and its lifetimes never expire.
510 	 */
511 	pr0.ndpr_raf_onlink = 1;
512 	pr0.ndpr_raf_auto = 1;	/* probably meaningless */
513 	pr0.ndpr_vltime = ND6_INFINITE_LIFETIME;
514 	pr0.ndpr_pltime = ND6_INFINITE_LIFETIME;
515 	/*
516 	 * Since there is no other link-local addresses, nd6_prefix_lookup()
517 	 * probably returns NULL.  However, we cannot always expect the result.
518 	 * For example, if we first remove the (only) existing link-local
519 	 * address, and then reconfigure another one, the prefix is still
520 	 * valid with referring to the old link-local address.
521 	 */
522 	if (nd6_prefix_lookup(&pr0) == NULL) {
523 		if ((error = nd6_prelist_add(&pr0, NULL, NULL)) != 0)
524 			return (error);
525 	}
526 
527 	return 0;
528 }
529 
530 static int
531 in6_ifattach_loopback(ifp)
532 	struct ifnet *ifp;	/* must be IFT_LOOP */
533 {
534 	struct in6_aliasreq ifra;
535 	int error;
536 
537 	bzero(&ifra, sizeof(ifra));
538 
539 	/*
540 	 * in6_update_ifa() does not use ifra_name, but we accurately set it
541 	 * for safety.
542 	 */
543 	strncpy(ifra.ifra_name, if_name(ifp), sizeof(ifra.ifra_name));
544 
545 	ifra.ifra_prefixmask.sin6_len = sizeof(struct sockaddr_in6);
546 	ifra.ifra_prefixmask.sin6_family = AF_INET6;
547 	ifra.ifra_prefixmask.sin6_addr = in6mask128;
548 
549 	/*
550 	 * Always initialize ia_dstaddr (= broadcast address) to loopback
551 	 * address.  Follows IPv4 practice - see in_ifinit().
552 	 */
553 	ifra.ifra_dstaddr.sin6_len = sizeof(struct sockaddr_in6);
554 	ifra.ifra_dstaddr.sin6_family = AF_INET6;
555 	ifra.ifra_dstaddr.sin6_addr = in6addr_loopback;
556 
557 	ifra.ifra_addr.sin6_len = sizeof(struct sockaddr_in6);
558 	ifra.ifra_addr.sin6_family = AF_INET6;
559 	ifra.ifra_addr.sin6_addr = in6addr_loopback;
560 
561 	/* the loopback  address should NEVER expire. */
562 	ifra.ifra_lifetime.ia6t_vltime = ND6_INFINITE_LIFETIME;
563 	ifra.ifra_lifetime.ia6t_pltime = ND6_INFINITE_LIFETIME;
564 
565 	/* we don't need to perform DAD on loopback interfaces. */
566 	ifra.ifra_flags |= IN6_IFF_NODAD;
567 
568 	/* skip registration to the prefix list. XXX should be temporary. */
569 	ifra.ifra_flags |= IN6_IFF_NOPFX;
570 
571 	/*
572 	 * We are sure that this is a newly assigned address, so we can set
573 	 * NULL to the 3rd arg.
574 	 */
575 	if ((error = in6_update_ifa(ifp, &ifra, NULL, 0)) != 0) {
576 		nd6log((LOG_ERR, "in6_ifattach_loopback: failed to configure "
577 		    "the loopback address on %s (errno=%d)\n",
578 		    if_name(ifp), error));
579 		return (-1);
580 	}
581 
582 	return 0;
583 }
584 
585 /*
586  * compute NI group address, based on the current hostname setting.
587  * see draft-ietf-ipngwg-icmp-name-lookup-* (04 and later).
588  *
589  * when ifp == NULL, the caller is responsible for filling scopeid.
590  */
591 int
592 in6_nigroup(ifp, name, namelen, in6)
593 	struct ifnet *ifp;
594 	const char *name;
595 	int namelen;
596 	struct in6_addr *in6;
597 {
598 	const char *p;
599 	u_char *q;
600 	MD5_CTX ctxt;
601 	u_int8_t digest[16];
602 	char l;
603 	char n[64];	/* a single label must not exceed 63 chars */
604 
605 	if (!namelen || !name)
606 		return -1;
607 
608 	p = name;
609 	while (p && *p && *p != '.' && p - name < namelen)
610 		p++;
611 	if (p - name > sizeof(n) - 1)
612 		return -1;	/* label too long */
613 	l = p - name;
614 	strncpy(n, name, l);
615 	n[(int)l] = '\0';
616 	for (q = n; *q; q++) {
617 		if ('A' <= *q && *q <= 'Z')
618 			*q = *q - 'A' + 'a';
619 	}
620 
621 	/* generate 8 bytes of pseudo-random value. */
622 	bzero(&ctxt, sizeof(ctxt));
623 	MD5Init(&ctxt);
624 	MD5Update(&ctxt, &l, sizeof(l));
625 	MD5Update(&ctxt, n, l);
626 	MD5Final(digest, &ctxt);
627 
628 	bzero(in6, sizeof(*in6));
629 	in6->s6_addr16[0] = IPV6_ADDR_INT16_MLL;
630 	in6->s6_addr8[11] = 2;
631 	bcopy(digest, &in6->s6_addr32[3], sizeof(in6->s6_addr32[3]));
632 	if (in6_setscope(in6, ifp, NULL))
633 		return (-1); /* XXX: should not fail */
634 
635 	return 0;
636 }
637 
638 /*
639  * XXX multiple loopback interface needs more care.  for instance,
640  * nodelocal address needs to be configured onto only one of them.
641  * XXX multiple link-local address case
642  */
643 void
644 in6_ifattach(ifp, altifp)
645 	struct ifnet *ifp;
646 	struct ifnet *altifp;	/* secondary EUI64 source */
647 {
648 	struct in6_ifaddr *ia;
649 	struct in6_addr in6;
650 
651 	/* some of the interfaces are inherently not IPv6 capable */
652 	switch (ifp->if_type) {
653 	case IFT_PFLOG:
654 	case IFT_PFSYNC:
655 	case IFT_CARP:
656 		return;
657 	}
658 
659 	/*
660 	 * quirks based on interface type
661 	 */
662 	switch (ifp->if_type) {
663 #ifdef IFT_STF
664 	case IFT_STF:
665 		/*
666 		 * 6to4 interface is a very special kind of beast.
667 		 * no multicast, no linklocal.  RFC2529 specifies how to make
668 		 * linklocals for 6to4 interface, but there's no use and
669 		 * it is rather harmful to have one.
670 		 */
671 		goto statinit;
672 #endif
673 	default:
674 		break;
675 	}
676 
677 	/*
678 	 * usually, we require multicast capability to the interface
679 	 */
680 	if ((ifp->if_flags & IFF_MULTICAST) == 0) {
681 		nd6log((LOG_INFO, "in6_ifattach: "
682 		    "%s is not multicast capable, IPv6 not enabled\n",
683 		    if_name(ifp)));
684 		return;
685 	}
686 
687 	/*
688 	 * assign loopback address for loopback interface.
689 	 * XXX multiple loopback interface case.
690 	 */
691 	if ((ifp->if_flags & IFF_LOOPBACK) != 0) {
692 		in6 = in6addr_loopback;
693 		if (in6ifa_ifpwithaddr(ifp, &in6) == NULL) {
694 			if (in6_ifattach_loopback(ifp) != 0)
695 				return;
696 		}
697 	}
698 
699 	/*
700 	 * assign a link-local address, if there's none.
701 	 */
702 	if (ip6_auto_linklocal && ifp->if_type != IFT_BRIDGE) {
703 		ia = in6ifa_ifpforlinklocal(ifp, 0);
704 		if (ia == NULL) {
705 			if (in6_ifattach_linklocal(ifp, altifp) == 0) {
706 				/* linklocal address assigned */
707 			} else {
708 				/* failed to assign linklocal address. bark? */
709 			}
710 		}
711 	}
712 
713 #ifdef IFT_STF			/* XXX */
714 statinit:
715 #endif
716 
717 	/* update dynamically. */
718 	if (in6_maxmtu < ifp->if_mtu)
719 		in6_maxmtu = ifp->if_mtu;
720 }
721 
722 /*
723  * NOTE: in6_ifdetach() does not support loopback if at this moment.
724  * We don't need this function in bsdi, because interfaces are never removed
725  * from the ifnet list in bsdi.
726  */
727 void
728 in6_ifdetach(ifp)
729 	struct ifnet *ifp;
730 {
731 	struct in6_ifaddr *ia, *oia;
732 	struct ifaddr *ifa, *next;
733 	struct rtentry *rt;
734 	short rtflags;
735 	struct sockaddr_in6 sin6;
736 	struct in6_multi *in6m;
737 	struct in6_multi *in6m_next;
738 
739 	/* remove neighbor management table */
740 	nd6_purge(ifp);
741 
742 	/* nuke any of IPv6 addresses we have */
743 	for (ifa = ifp->if_addrlist.tqh_first; ifa; ifa = next) {
744 		next = ifa->ifa_list.tqe_next;
745 		if (ifa->ifa_addr->sa_family != AF_INET6)
746 			continue;
747 		in6_purgeaddr(ifa);
748 	}
749 
750 	/* undo everything done by in6_ifattach(), just in case */
751 	for (ifa = ifp->if_addrlist.tqh_first; ifa; ifa = next) {
752 		next = ifa->ifa_list.tqe_next;
753 
754 		if (ifa->ifa_addr->sa_family != AF_INET6
755 		 || !IN6_IS_ADDR_LINKLOCAL(&satosin6(&ifa->ifa_addr)->sin6_addr)) {
756 			continue;
757 		}
758 
759 		ia = (struct in6_ifaddr *)ifa;
760 
761 		/* remove from the routing table */
762 		if ((ia->ia_flags & IFA_ROUTE) &&
763 		    (rt = rtalloc1((struct sockaddr *)&ia->ia_addr, 0, 0UL))) {
764 			rtflags = rt->rt_flags;
765 			rtfree(rt);
766 			rtrequest(RTM_DELETE, (struct sockaddr *)&ia->ia_addr,
767 			    (struct sockaddr *)&ia->ia_addr,
768 			    (struct sockaddr *)&ia->ia_prefixmask,
769 			    rtflags, (struct rtentry **)0);
770 		}
771 
772 		/* remove from the linked list */
773 		TAILQ_REMOVE(&ifp->if_addrlist, (struct ifaddr *)ia, ifa_list);
774 		IFAFREE(&ia->ia_ifa);
775 
776 		/* also remove from the IPv6 address chain(itojun&jinmei) */
777 		oia = ia;
778 		if (oia == (ia = in6_ifaddr))
779 			in6_ifaddr = ia->ia_next;
780 		else {
781 			while (ia->ia_next && (ia->ia_next != oia))
782 				ia = ia->ia_next;
783 			if (ia->ia_next)
784 				ia->ia_next = oia->ia_next;
785 			else {
786 				nd6log((LOG_ERR,
787 				    "%s: didn't unlink in6ifaddr from list\n",
788 				    if_name(ifp)));
789 			}
790 		}
791 
792 		IFAFREE(&oia->ia_ifa);
793 	}
794 
795 	/* leave from all multicast groups joined */
796 
797 	in6_pcbpurgeif0(&udbinfo, ifp);
798 	in6_pcbpurgeif0(&ripcbinfo, ifp);
799 
800 	for (in6m = LIST_FIRST(&in6_multihead); in6m; in6m = in6m_next) {
801 		in6m_next = LIST_NEXT(in6m, in6m_entry);
802 		if (in6m->in6m_ifp != ifp)
803 			continue;
804 		in6_delmulti(in6m);
805 		in6m = NULL;
806 	}
807 
808 	/*
809 	 * remove neighbor management table.  we call it twice just to make
810 	 * sure we nuke everything.  maybe we need just one call.
811 	 * XXX: since the first call did not release addresses, some prefixes
812 	 * might remain.  We should call nd6_purge() again to release the
813 	 * prefixes after removing all addresses above.
814 	 * (Or can we just delay calling nd6_purge until at this point?)
815 	 */
816 	nd6_purge(ifp);
817 
818 	/* remove route to link-local allnodes multicast (ff02::1) */
819 	bzero(&sin6, sizeof(sin6));
820 	sin6.sin6_len = sizeof(struct sockaddr_in6);
821 	sin6.sin6_family = AF_INET6;
822 	sin6.sin6_addr = in6addr_linklocal_allnodes;
823 	if (in6_setscope(&sin6.sin6_addr, ifp, NULL))
824 		/* XXX: should not fail */
825 		return;
826 	/* XXX grab lock first to avoid LOR */
827 	if (rt_tables[AF_INET6] != NULL) {
828 		RADIX_NODE_HEAD_LOCK(rt_tables[AF_INET6]);
829 		rt = rtalloc1((struct sockaddr *)&sin6, 0, 0UL);
830 		if (rt) {
831 			if (rt->rt_ifp == ifp)
832 				rtexpunge(rt);
833 			RTFREE_LOCKED(rt);
834 		}
835 		RADIX_NODE_HEAD_UNLOCK(rt_tables[AF_INET6]);
836 	}
837 }
838 
839 int
840 in6_get_tmpifid(ifp, retbuf, baseid, generate)
841 	struct ifnet *ifp;
842 	u_int8_t *retbuf;
843 	const u_int8_t *baseid;
844 	int generate;
845 {
846 	u_int8_t nullbuf[8];
847 	struct nd_ifinfo *ndi = ND_IFINFO(ifp);
848 
849 	bzero(nullbuf, sizeof(nullbuf));
850 	if (bcmp(ndi->randomid, nullbuf, sizeof(nullbuf)) == 0) {
851 		/* we've never created a random ID.  Create a new one. */
852 		generate = 1;
853 	}
854 
855 	if (generate) {
856 		bcopy(baseid, ndi->randomseed1, sizeof(ndi->randomseed1));
857 
858 		/* generate_tmp_ifid will update seedn and buf */
859 		(void)generate_tmp_ifid(ndi->randomseed0, ndi->randomseed1,
860 		    ndi->randomid);
861 	}
862 	bcopy(ndi->randomid, retbuf, 8);
863 
864 	return (0);
865 }
866 
867 void
868 in6_tmpaddrtimer(ignored_arg)
869 	void *ignored_arg;
870 {
871 	struct nd_ifinfo *ndi;
872 	u_int8_t nullbuf[8];
873 	struct ifnet *ifp;
874 	int s = splnet();
875 
876 	callout_reset(&in6_tmpaddrtimer_ch,
877 	    (ip6_temp_preferred_lifetime - ip6_desync_factor -
878 	    ip6_temp_regen_advance) * hz, in6_tmpaddrtimer, NULL);
879 
880 	bzero(nullbuf, sizeof(nullbuf));
881 	for (ifp = TAILQ_FIRST(&ifnet); ifp; ifp = TAILQ_NEXT(ifp, if_list)) {
882 		ndi = ND_IFINFO(ifp);
883 		if (bcmp(ndi->randomid, nullbuf, sizeof(nullbuf)) != 0) {
884 			/*
885 			 * We've been generating a random ID on this interface.
886 			 * Create a new one.
887 			 */
888 			(void)generate_tmp_ifid(ndi->randomseed0,
889 			    ndi->randomseed1, ndi->randomid);
890 		}
891 	}
892 
893 	splx(s);
894 }
895