in6_ifattach.c revision 197996
1/*-
2 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 3. Neither the name of the project nor the names of its contributors
14 *    may be used to endorse or promote products derived from this software
15 *    without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 *	$KAME: in6_ifattach.c,v 1.118 2001/05/24 07:44:00 itojun Exp $
30 */
31
32#include <sys/cdefs.h>
33__FBSDID("$FreeBSD: head/sys/netinet6/in6_ifattach.c 197996 2009-10-12 18:54:02Z hrs $");
34
35#include <sys/param.h>
36#include <sys/systm.h>
37#include <sys/malloc.h>
38#include <sys/socket.h>
39#include <sys/sockio.h>
40#include <sys/jail.h>
41#include <sys/kernel.h>
42#include <sys/proc.h>
43#include <sys/syslog.h>
44#include <sys/md5.h>
45
46#include <net/if.h>
47#include <net/if_dl.h>
48#include <net/if_types.h>
49#include <net/route.h>
50#include <net/vnet.h>
51
52#include <netinet/in.h>
53#include <netinet/in_var.h>
54#include <netinet/if_ether.h>
55#include <netinet/in_pcb.h>
56#include <netinet/ip_var.h>
57#include <netinet/udp.h>
58#include <netinet/udp_var.h>
59
60#include <netinet/ip6.h>
61#include <netinet6/ip6_var.h>
62#include <netinet6/in6_var.h>
63#include <netinet6/in6_pcb.h>
64#include <netinet6/in6_ifattach.h>
65#include <netinet6/ip6_var.h>
66#include <netinet6/nd6.h>
67#include <netinet6/mld6_var.h>
68#include <netinet6/scope6_var.h>
69
70VNET_DEFINE(unsigned long, in6_maxmtu);
71VNET_DEFINE(int, ip6_auto_linklocal);
72VNET_DEFINE(struct callout, in6_tmpaddrtimer_ch);
73
74#define	V_in6_tmpaddrtimer_ch		VNET(in6_tmpaddrtimer_ch)
75
76VNET_DECLARE(struct inpcbinfo, ripcbinfo);
77#define	V_ripcbinfo			VNET(ripcbinfo)
78
79static int get_rand_ifid(struct ifnet *, struct in6_addr *);
80static int generate_tmp_ifid(u_int8_t *, const u_int8_t *, u_int8_t *);
81static int get_ifid(struct ifnet *, struct ifnet *, struct in6_addr *);
82static int in6_ifattach_linklocal(struct ifnet *, struct ifnet *);
83static int in6_ifattach_loopback(struct ifnet *);
84static void in6_purgemaddrs(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 * in6 - upper 64bits are preserved
105 */
106static int
107get_rand_ifid(struct ifnet *ifp, struct in6_addr *in6)
108{
109	MD5_CTX ctxt;
110	struct prison *pr;
111	u_int8_t digest[16];
112	int hostnamelen;
113
114	pr = curthread->td_ucred->cr_prison;
115	mtx_lock(&pr->pr_mtx);
116	hostnamelen = strlen(pr->pr_hostname);
117#if 0
118	/* we need at least several letters as seed for ifid */
119	if (hostnamelen < 3) {
120		mtx_unlock(&pr->pr_mtx);
121		return -1;
122	}
123#endif
124
125	/* generate 8 bytes of pseudo-random value. */
126	bzero(&ctxt, sizeof(ctxt));
127	MD5Init(&ctxt);
128	MD5Update(&ctxt, pr->pr_hostname, hostnamelen);
129	mtx_unlock(&pr->pr_mtx);
130	MD5Final(digest, &ctxt);
131
132	/* assumes sizeof(digest) > sizeof(ifid) */
133	bcopy(digest, &in6->s6_addr[8], 8);
134
135	/* make sure to set "u" bit to local, and "g" bit to individual. */
136	in6->s6_addr[8] &= ~EUI64_GBIT;	/* g bit to "individual" */
137	in6->s6_addr[8] |= EUI64_UBIT;	/* u bit to "local" */
138
139	/* convert EUI64 into IPv6 interface identifier */
140	EUI64_TO_IFID(in6);
141
142	return 0;
143}
144
145static int
146generate_tmp_ifid(u_int8_t *seed0, const u_int8_t *seed1, u_int8_t *ret)
147{
148	MD5_CTX ctxt;
149	u_int8_t seed[16], digest[16], nullbuf[8];
150	u_int32_t val32;
151
152	/* If there's no history, start with a random seed. */
153	bzero(nullbuf, sizeof(nullbuf));
154	if (bcmp(nullbuf, seed0, sizeof(nullbuf)) == 0) {
155		int i;
156
157		for (i = 0; i < 2; i++) {
158			val32 = arc4random();
159			bcopy(&val32, seed + sizeof(val32) * i, sizeof(val32));
160		}
161	} else
162		bcopy(seed0, seed, 8);
163
164	/* copy the right-most 64-bits of the given address */
165	/* XXX assumption on the size of IFID */
166	bcopy(seed1, &seed[8], 8);
167
168	if (0) {		/* for debugging purposes only */
169		int i;
170
171		printf("generate_tmp_ifid: new randomized ID from: ");
172		for (i = 0; i < 16; i++)
173			printf("%02x", seed[i]);
174		printf(" ");
175	}
176
177	/* generate 16 bytes of pseudo-random value. */
178	bzero(&ctxt, sizeof(ctxt));
179	MD5Init(&ctxt);
180	MD5Update(&ctxt, seed, sizeof(seed));
181	MD5Final(digest, &ctxt);
182
183	/*
184	 * RFC 3041 3.2.1. (3)
185	 * Take the left-most 64-bits of the MD5 digest and set bit 6 (the
186	 * left-most bit is numbered 0) to zero.
187	 */
188	bcopy(digest, ret, 8);
189	ret[0] &= ~EUI64_UBIT;
190
191	/*
192	 * XXX: we'd like to ensure that the generated value is not zero
193	 * for simplicity.  If the caclculated digest happens to be zero,
194	 * use a random non-zero value as the last resort.
195	 */
196	if (bcmp(nullbuf, ret, sizeof(nullbuf)) == 0) {
197		nd6log((LOG_INFO,
198		    "generate_tmp_ifid: computed MD5 value is zero.\n"));
199
200		val32 = arc4random();
201		val32 = 1 + (val32 % (0xffffffff - 1));
202	}
203
204	/*
205	 * RFC 3041 3.2.1. (4)
206	 * Take the rightmost 64-bits of the MD5 digest and save them in
207	 * stable storage as the history value to be used in the next
208	 * iteration of the algorithm.
209	 */
210	bcopy(&digest[8], seed0, 8);
211
212	if (0) {		/* for debugging purposes only */
213		int i;
214
215		printf("to: ");
216		for (i = 0; i < 16; i++)
217			printf("%02x", digest[i]);
218		printf("\n");
219	}
220
221	return 0;
222}
223
224/*
225 * Get interface identifier for the specified interface.
226 * XXX assumes single sockaddr_dl (AF_LINK address) per an interface
227 *
228 * in6 - upper 64bits are preserved
229 */
230int
231in6_get_hw_ifid(struct ifnet *ifp, struct in6_addr *in6)
232{
233	struct ifaddr *ifa;
234	struct sockaddr_dl *sdl;
235	u_int8_t *addr;
236	size_t addrlen;
237	static u_int8_t allzero[8] = { 0, 0, 0, 0, 0, 0, 0, 0 };
238	static u_int8_t allone[8] =
239		{ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
240
241	IF_ADDR_LOCK(ifp);
242	TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
243		if (ifa->ifa_addr->sa_family != AF_LINK)
244			continue;
245		sdl = (struct sockaddr_dl *)ifa->ifa_addr;
246		if (sdl == NULL)
247			continue;
248		if (sdl->sdl_alen == 0)
249			continue;
250
251		goto found;
252	}
253	IF_ADDR_UNLOCK(ifp);
254
255	return -1;
256
257found:
258	IF_ADDR_LOCK_ASSERT(ifp);
259	addr = LLADDR(sdl);
260	addrlen = sdl->sdl_alen;
261
262	/* get EUI64 */
263	switch (ifp->if_type) {
264	case IFT_ETHER:
265	case IFT_FDDI:
266	case IFT_ISO88025:
267	case IFT_ATM:
268	case IFT_IEEE1394:
269#ifdef IFT_IEEE80211
270	case IFT_IEEE80211:
271#endif
272		/* IEEE802/EUI64 cases - what others? */
273		/* IEEE1394 uses 16byte length address starting with EUI64 */
274		if (addrlen > 8)
275			addrlen = 8;
276
277		/* look at IEEE802/EUI64 only */
278		if (addrlen != 8 && addrlen != 6) {
279			IF_ADDR_UNLOCK(ifp);
280			return -1;
281		}
282
283		/*
284		 * check for invalid MAC address - on bsdi, we see it a lot
285		 * since wildboar configures all-zero MAC on pccard before
286		 * card insertion.
287		 */
288		if (bcmp(addr, allzero, addrlen) == 0) {
289			IF_ADDR_UNLOCK(ifp);
290			return -1;
291		}
292		if (bcmp(addr, allone, addrlen) == 0) {
293			IF_ADDR_UNLOCK(ifp);
294			return -1;
295		}
296
297		/* make EUI64 address */
298		if (addrlen == 8)
299			bcopy(addr, &in6->s6_addr[8], 8);
300		else if (addrlen == 6) {
301			in6->s6_addr[8] = addr[0];
302			in6->s6_addr[9] = addr[1];
303			in6->s6_addr[10] = addr[2];
304			in6->s6_addr[11] = 0xff;
305			in6->s6_addr[12] = 0xfe;
306			in6->s6_addr[13] = addr[3];
307			in6->s6_addr[14] = addr[4];
308			in6->s6_addr[15] = addr[5];
309		}
310		break;
311
312	case IFT_ARCNET:
313		if (addrlen != 1) {
314			IF_ADDR_UNLOCK(ifp);
315			return -1;
316		}
317		if (!addr[0]) {
318			IF_ADDR_UNLOCK(ifp);
319			return -1;
320		}
321
322		bzero(&in6->s6_addr[8], 8);
323		in6->s6_addr[15] = addr[0];
324
325		/*
326		 * due to insufficient bitwidth, we mark it local.
327		 */
328		in6->s6_addr[8] &= ~EUI64_GBIT;	/* g bit to "individual" */
329		in6->s6_addr[8] |= EUI64_UBIT;	/* u bit to "local" */
330		break;
331
332	case IFT_GIF:
333#ifdef IFT_STF
334	case IFT_STF:
335#endif
336		/*
337		 * RFC2893 says: "SHOULD use IPv4 address as ifid source".
338		 * however, IPv4 address is not very suitable as unique
339		 * identifier source (can be renumbered).
340		 * we don't do this.
341		 */
342		IF_ADDR_UNLOCK(ifp);
343		return -1;
344
345	default:
346		IF_ADDR_UNLOCK(ifp);
347		return -1;
348	}
349
350	/* sanity check: g bit must not indicate "group" */
351	if (EUI64_GROUP(in6)) {
352		IF_ADDR_UNLOCK(ifp);
353		return -1;
354	}
355
356	/* convert EUI64 into IPv6 interface identifier */
357	EUI64_TO_IFID(in6);
358
359	/*
360	 * sanity check: ifid must not be all zero, avoid conflict with
361	 * subnet router anycast
362	 */
363	if ((in6->s6_addr[8] & ~(EUI64_GBIT | EUI64_UBIT)) == 0x00 &&
364	    bcmp(&in6->s6_addr[9], allzero, 7) == 0) {
365		IF_ADDR_UNLOCK(ifp);
366		return -1;
367	}
368
369	IF_ADDR_UNLOCK(ifp);
370	return 0;
371}
372
373/*
374 * Get interface identifier for the specified interface.  If it is not
375 * available on ifp0, borrow interface identifier from other information
376 * sources.
377 *
378 * altifp - secondary EUI64 source
379 */
380static int
381get_ifid(struct ifnet *ifp0, struct ifnet *altifp,
382    struct in6_addr *in6)
383{
384	struct ifnet *ifp;
385
386	/* first, try to get it from the interface itself */
387	if (in6_get_hw_ifid(ifp0, in6) == 0) {
388		nd6log((LOG_DEBUG, "%s: got interface identifier from itself\n",
389		    if_name(ifp0)));
390		goto success;
391	}
392
393	/* try secondary EUI64 source. this basically is for ATM PVC */
394	if (altifp && in6_get_hw_ifid(altifp, in6) == 0) {
395		nd6log((LOG_DEBUG, "%s: got interface identifier from %s\n",
396		    if_name(ifp0), if_name(altifp)));
397		goto success;
398	}
399
400	/* next, try to get it from some other hardware interface */
401	IFNET_RLOCK_NOSLEEP();
402	for (ifp = V_ifnet.tqh_first; ifp; ifp = ifp->if_list.tqe_next) {
403		if (ifp == ifp0)
404			continue;
405		if (in6_get_hw_ifid(ifp, in6) != 0)
406			continue;
407
408		/*
409		 * to borrow ifid from other interface, ifid needs to be
410		 * globally unique
411		 */
412		if (IFID_UNIVERSAL(in6)) {
413			nd6log((LOG_DEBUG,
414			    "%s: borrow interface identifier from %s\n",
415			    if_name(ifp0), if_name(ifp)));
416			IFNET_RUNLOCK_NOSLEEP();
417			goto success;
418		}
419	}
420	IFNET_RUNLOCK_NOSLEEP();
421
422	/* last resort: get from random number source */
423	if (get_rand_ifid(ifp, in6) == 0) {
424		nd6log((LOG_DEBUG,
425		    "%s: interface identifier generated by random number\n",
426		    if_name(ifp0)));
427		goto success;
428	}
429
430	printf("%s: failed to get interface identifier\n", if_name(ifp0));
431	return -1;
432
433success:
434	nd6log((LOG_INFO, "%s: ifid: %02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x\n",
435	    if_name(ifp0), in6->s6_addr[8], in6->s6_addr[9], in6->s6_addr[10],
436	    in6->s6_addr[11], in6->s6_addr[12], in6->s6_addr[13],
437	    in6->s6_addr[14], in6->s6_addr[15]));
438	return 0;
439}
440
441/*
442 * altifp - secondary EUI64 source
443 */
444static int
445in6_ifattach_linklocal(struct ifnet *ifp, struct ifnet *altifp)
446{
447	struct in6_ifaddr *ia;
448	struct in6_aliasreq ifra;
449	struct nd_prefixctl pr0;
450	int i, error;
451
452	/*
453	 * configure link-local address.
454	 */
455	bzero(&ifra, sizeof(ifra));
456
457	/*
458	 * in6_update_ifa() does not use ifra_name, but we accurately set it
459	 * for safety.
460	 */
461	strncpy(ifra.ifra_name, if_name(ifp), sizeof(ifra.ifra_name));
462
463	ifra.ifra_addr.sin6_family = AF_INET6;
464	ifra.ifra_addr.sin6_len = sizeof(struct sockaddr_in6);
465	ifra.ifra_addr.sin6_addr.s6_addr32[0] = htonl(0xfe800000);
466	ifra.ifra_addr.sin6_addr.s6_addr32[1] = 0;
467	if ((ifp->if_flags & IFF_LOOPBACK) != 0) {
468		ifra.ifra_addr.sin6_addr.s6_addr32[2] = 0;
469		ifra.ifra_addr.sin6_addr.s6_addr32[3] = htonl(1);
470	} else {
471		if (get_ifid(ifp, altifp, &ifra.ifra_addr.sin6_addr) != 0) {
472			nd6log((LOG_ERR,
473			    "%s: no ifid available\n", if_name(ifp)));
474			return (-1);
475		}
476	}
477	if (in6_setscope(&ifra.ifra_addr.sin6_addr, ifp, NULL))
478		return (-1);
479
480	ifra.ifra_prefixmask.sin6_len = sizeof(struct sockaddr_in6);
481	ifra.ifra_prefixmask.sin6_family = AF_INET6;
482	ifra.ifra_prefixmask.sin6_addr = in6mask64;
483	/* link-local addresses should NEVER expire. */
484	ifra.ifra_lifetime.ia6t_vltime = ND6_INFINITE_LIFETIME;
485	ifra.ifra_lifetime.ia6t_pltime = ND6_INFINITE_LIFETIME;
486
487	/*
488	 * Now call in6_update_ifa() to do a bunch of procedures to configure
489	 * a link-local address. We can set the 3rd argument to NULL, because
490	 * we know there's no other link-local address on the interface
491	 * and therefore we are adding one (instead of updating one).
492	 */
493	if ((error = in6_update_ifa(ifp, &ifra, NULL,
494				    IN6_IFAUPDATE_DADDELAY)) != 0) {
495		/*
496		 * XXX: When the interface does not support IPv6, this call
497		 * would fail in the SIOCSIFADDR ioctl.  I believe the
498		 * notification is rather confusing in this case, so just
499		 * suppress it.  (jinmei@kame.net 20010130)
500		 */
501		if (error != EAFNOSUPPORT)
502			nd6log((LOG_NOTICE, "in6_ifattach_linklocal: failed to "
503			    "configure a link-local address on %s "
504			    "(errno=%d)\n",
505			    if_name(ifp), error));
506		return (-1);
507	}
508
509	ia = in6ifa_ifpforlinklocal(ifp, 0); /* ia must not be NULL */
510#ifdef DIAGNOSTIC
511	if (!ia) {
512		panic("ia == NULL in in6_ifattach_linklocal");
513		/* NOTREACHED */
514	}
515#endif
516	ifa_free(&ia->ia_ifa);
517
518	/*
519	 * Make the link-local prefix (fe80::%link/64) as on-link.
520	 * Since we'd like to manage prefixes separately from addresses,
521	 * we make an ND6 prefix structure for the link-local prefix,
522	 * and add it to the prefix list as a never-expire prefix.
523	 * XXX: this change might affect some existing code base...
524	 */
525	bzero(&pr0, sizeof(pr0));
526	pr0.ndpr_ifp = ifp;
527	/* this should be 64 at this moment. */
528	pr0.ndpr_plen = in6_mask2len(&ifra.ifra_prefixmask.sin6_addr, NULL);
529	pr0.ndpr_prefix = ifra.ifra_addr;
530	/* apply the mask for safety. (nd6_prelist_add will apply it again) */
531	for (i = 0; i < 4; i++) {
532		pr0.ndpr_prefix.sin6_addr.s6_addr32[i] &=
533		    in6mask64.s6_addr32[i];
534	}
535	/*
536	 * Initialize parameters.  The link-local prefix must always be
537	 * on-link, and its lifetimes never expire.
538	 */
539	pr0.ndpr_raf_onlink = 1;
540	pr0.ndpr_raf_auto = 1;	/* probably meaningless */
541	pr0.ndpr_vltime = ND6_INFINITE_LIFETIME;
542	pr0.ndpr_pltime = ND6_INFINITE_LIFETIME;
543	/*
544	 * Since there is no other link-local addresses, nd6_prefix_lookup()
545	 * probably returns NULL.  However, we cannot always expect the result.
546	 * For example, if we first remove the (only) existing link-local
547	 * address, and then reconfigure another one, the prefix is still
548	 * valid with referring to the old link-local address.
549	 */
550	if (nd6_prefix_lookup(&pr0) == NULL) {
551		if ((error = nd6_prelist_add(&pr0, NULL, NULL)) != 0)
552			return (error);
553	}
554
555	return 0;
556}
557
558/*
559 * ifp - must be IFT_LOOP
560 */
561static int
562in6_ifattach_loopback(struct ifnet *ifp)
563{
564	struct in6_aliasreq ifra;
565	int error;
566
567	bzero(&ifra, sizeof(ifra));
568
569	/*
570	 * in6_update_ifa() does not use ifra_name, but we accurately set it
571	 * for safety.
572	 */
573	strncpy(ifra.ifra_name, if_name(ifp), sizeof(ifra.ifra_name));
574
575	ifra.ifra_prefixmask.sin6_len = sizeof(struct sockaddr_in6);
576	ifra.ifra_prefixmask.sin6_family = AF_INET6;
577	ifra.ifra_prefixmask.sin6_addr = in6mask128;
578
579	/*
580	 * Always initialize ia_dstaddr (= broadcast address) to loopback
581	 * address.  Follows IPv4 practice - see in_ifinit().
582	 */
583	ifra.ifra_dstaddr.sin6_len = sizeof(struct sockaddr_in6);
584	ifra.ifra_dstaddr.sin6_family = AF_INET6;
585	ifra.ifra_dstaddr.sin6_addr = in6addr_loopback;
586
587	ifra.ifra_addr.sin6_len = sizeof(struct sockaddr_in6);
588	ifra.ifra_addr.sin6_family = AF_INET6;
589	ifra.ifra_addr.sin6_addr = in6addr_loopback;
590
591	/* the loopback  address should NEVER expire. */
592	ifra.ifra_lifetime.ia6t_vltime = ND6_INFINITE_LIFETIME;
593	ifra.ifra_lifetime.ia6t_pltime = ND6_INFINITE_LIFETIME;
594
595	/* we don't need to perform DAD on loopback interfaces. */
596	ifra.ifra_flags |= IN6_IFF_NODAD;
597
598	/* skip registration to the prefix list. XXX should be temporary. */
599	ifra.ifra_flags |= IN6_IFF_NOPFX;
600
601	/*
602	 * We are sure that this is a newly assigned address, so we can set
603	 * NULL to the 3rd arg.
604	 */
605	if ((error = in6_update_ifa(ifp, &ifra, NULL, 0)) != 0) {
606		nd6log((LOG_ERR, "in6_ifattach_loopback: failed to configure "
607		    "the loopback address on %s (errno=%d)\n",
608		    if_name(ifp), error));
609		return (-1);
610	}
611
612	return 0;
613}
614
615/*
616 * compute NI group address, based on the current hostname setting.
617 * see draft-ietf-ipngwg-icmp-name-lookup-* (04 and later).
618 *
619 * when ifp == NULL, the caller is responsible for filling scopeid.
620 */
621int
622in6_nigroup(struct ifnet *ifp, const char *name, int namelen,
623    struct in6_addr *in6)
624{
625	struct prison *pr;
626	const char *p;
627	u_char *q;
628	MD5_CTX ctxt;
629	u_int8_t digest[16];
630	char l;
631	char n[64];	/* a single label must not exceed 63 chars */
632
633	/*
634	 * If no name is given and namelen is -1,
635	 * we try to do the hostname lookup ourselves.
636	 */
637	if (!name && namelen == -1) {
638		pr = curthread->td_ucred->cr_prison;
639		mtx_lock(&pr->pr_mtx);
640		name = pr->pr_hostname;
641		namelen = strlen(name);
642	} else
643		pr = NULL;
644	if (!name || !namelen) {
645		if (pr != NULL)
646			mtx_unlock(&pr->pr_mtx);
647		return -1;
648	}
649
650	p = name;
651	while (p && *p && *p != '.' && p - name < namelen)
652		p++;
653	if (p == name || p - name > sizeof(n) - 1) {
654		if (pr != NULL)
655			mtx_unlock(&pr->pr_mtx);
656		return -1;	/* label too long */
657	}
658	l = p - name;
659	strncpy(n, name, l);
660	if (pr != NULL)
661		mtx_unlock(&pr->pr_mtx);
662	n[(int)l] = '\0';
663	for (q = n; *q; q++) {
664		if ('A' <= *q && *q <= 'Z')
665			*q = *q - 'A' + 'a';
666	}
667
668	/* generate 8 bytes of pseudo-random value. */
669	bzero(&ctxt, sizeof(ctxt));
670	MD5Init(&ctxt);
671	MD5Update(&ctxt, &l, sizeof(l));
672	MD5Update(&ctxt, n, l);
673	MD5Final(digest, &ctxt);
674
675	bzero(in6, sizeof(*in6));
676	in6->s6_addr16[0] = IPV6_ADDR_INT16_MLL;
677	in6->s6_addr8[11] = 2;
678	bcopy(digest, &in6->s6_addr32[3], sizeof(in6->s6_addr32[3]));
679	if (in6_setscope(in6, ifp, NULL))
680		return (-1); /* XXX: should not fail */
681
682	return 0;
683}
684
685/*
686 * XXX multiple loopback interface needs more care.  for instance,
687 * nodelocal address needs to be configured onto only one of them.
688 * XXX multiple link-local address case
689 *
690 * altifp - secondary EUI64 source
691 */
692void
693in6_ifattach(struct ifnet *ifp, struct ifnet *altifp)
694{
695	struct in6_ifaddr *ia;
696	struct in6_addr in6;
697
698	/* some of the interfaces are inherently not IPv6 capable */
699	switch (ifp->if_type) {
700	case IFT_PFLOG:
701	case IFT_PFSYNC:
702	case IFT_CARP:
703		return;
704	}
705
706	/*
707	 * quirks based on interface type
708	 */
709	switch (ifp->if_type) {
710#ifdef IFT_STF
711	case IFT_STF:
712		/*
713		 * 6to4 interface is a very special kind of beast.
714		 * no multicast, no linklocal.  RFC2529 specifies how to make
715		 * linklocals for 6to4 interface, but there's no use and
716		 * it is rather harmful to have one.
717		 */
718		goto statinit;
719#endif
720	default:
721		break;
722	}
723
724	/*
725	 * usually, we require multicast capability to the interface
726	 */
727	if ((ifp->if_flags & IFF_MULTICAST) == 0) {
728		nd6log((LOG_INFO, "in6_ifattach: "
729		    "%s is not multicast capable, IPv6 not enabled\n",
730		    if_name(ifp)));
731		return;
732	}
733
734	/*
735	 * assign loopback address for loopback interface.
736	 * XXX multiple loopback interface case.
737	 */
738	if ((ifp->if_flags & IFF_LOOPBACK) != 0) {
739		struct ifaddr *ifa;
740
741		in6 = in6addr_loopback;
742		ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &in6);
743		if (ifa == NULL) {
744			if (in6_ifattach_loopback(ifp) != 0)
745				return;
746		} else
747			ifa_free(ifa);
748	}
749
750	/*
751	 * assign a link-local address, if there's none.
752	 */
753	if (ifp->if_type != IFT_BRIDGE &&
754	    !(ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED) &&
755	    ND_IFINFO(ifp)->flags & ND6_IFF_AUTO_LINKLOCAL) {
756		int error;
757
758		ia = in6ifa_ifpforlinklocal(ifp, 0);
759		if (ia == NULL) {
760			error = in6_ifattach_linklocal(ifp, altifp);
761#if 0
762			if (error)
763				log(LOG_NOTICE, "in6_ifattach_linklocal: "
764				    "failed to add a link-local addr to %s\n",
765				    if_name(ifp));
766#endif
767		} else
768			ifa_free(&ia->ia_ifa);
769	}
770
771#ifdef IFT_STF			/* XXX */
772statinit:
773#endif
774
775	/* update dynamically. */
776	if (V_in6_maxmtu < ifp->if_mtu)
777		V_in6_maxmtu = ifp->if_mtu;
778}
779
780/*
781 * NOTE: in6_ifdetach() does not support loopback if at this moment.
782 * We don't need this function in bsdi, because interfaces are never removed
783 * from the ifnet list in bsdi.
784 */
785void
786in6_ifdetach(struct ifnet *ifp)
787{
788	struct in6_ifaddr *ia;
789	struct ifaddr *ifa, *next;
790	struct radix_node_head *rnh;
791	struct rtentry *rt;
792	short rtflags;
793	struct sockaddr_in6 sin6;
794	struct in6_multi_mship *imm;
795
796	/* remove neighbor management table */
797	nd6_purge(ifp);
798
799	/* nuke any of IPv6 addresses we have */
800	TAILQ_FOREACH_SAFE(ifa, &ifp->if_addrhead, ifa_link, next) {
801		if (ifa->ifa_addr->sa_family != AF_INET6)
802			continue;
803		in6_purgeaddr(ifa);
804	}
805
806	/* undo everything done by in6_ifattach(), just in case */
807	TAILQ_FOREACH_SAFE(ifa, &ifp->if_addrhead, ifa_link, next) {
808		if (ifa->ifa_addr->sa_family != AF_INET6
809		 || !IN6_IS_ADDR_LINKLOCAL(&satosin6(&ifa->ifa_addr)->sin6_addr)) {
810			continue;
811		}
812
813		ia = (struct in6_ifaddr *)ifa;
814
815		/*
816		 * leave from multicast groups we have joined for the interface
817		 */
818		while ((imm = ia->ia6_memberships.lh_first) != NULL) {
819			LIST_REMOVE(imm, i6mm_chain);
820			in6_leavegroup(imm);
821		}
822
823		/* remove from the routing table */
824		if ((ia->ia_flags & IFA_ROUTE) &&
825		    (rt = rtalloc1((struct sockaddr *)&ia->ia_addr, 0, 0UL))) {
826			rtflags = rt->rt_flags;
827			RTFREE_LOCKED(rt);
828			rtrequest(RTM_DELETE, (struct sockaddr *)&ia->ia_addr,
829			    (struct sockaddr *)&ia->ia_addr,
830			    (struct sockaddr *)&ia->ia_prefixmask,
831			    rtflags, (struct rtentry **)0);
832		}
833
834		/* remove from the linked list */
835		IF_ADDR_LOCK(ifp);
836		TAILQ_REMOVE(&ifp->if_addrhead, ifa, ifa_link);
837		IF_ADDR_UNLOCK(ifp);
838		ifa_free(ifa);				/* if_addrhead */
839
840		IN6_IFADDR_WLOCK();
841		TAILQ_REMOVE(&V_in6_ifaddrhead, ia, ia_link);
842		IN6_IFADDR_WUNLOCK();
843		ifa_free(ifa);
844	}
845
846	in6_pcbpurgeif0(&V_udbinfo, ifp);
847	in6_pcbpurgeif0(&V_ripcbinfo, ifp);
848	/* leave from all multicast groups joined */
849	in6_purgemaddrs(ifp);
850
851	/*
852	 * remove neighbor management table.  we call it twice just to make
853	 * sure we nuke everything.  maybe we need just one call.
854	 * XXX: since the first call did not release addresses, some prefixes
855	 * might remain.  We should call nd6_purge() again to release the
856	 * prefixes after removing all addresses above.
857	 * (Or can we just delay calling nd6_purge until at this point?)
858	 */
859	nd6_purge(ifp);
860
861	/* remove route to link-local allnodes multicast (ff02::1) */
862	bzero(&sin6, sizeof(sin6));
863	sin6.sin6_len = sizeof(struct sockaddr_in6);
864	sin6.sin6_family = AF_INET6;
865	sin6.sin6_addr = in6addr_linklocal_allnodes;
866	if (in6_setscope(&sin6.sin6_addr, ifp, NULL))
867		/* XXX: should not fail */
868		return;
869	/* XXX grab lock first to avoid LOR */
870	rnh = rt_tables_get_rnh(0, AF_INET6);
871	if (rnh != NULL) {
872		RADIX_NODE_HEAD_LOCK(rnh);
873		rt = rtalloc1((struct sockaddr *)&sin6, 0, RTF_RNH_LOCKED);
874		if (rt) {
875			if (rt->rt_ifp == ifp)
876				rtexpunge(rt);
877			RTFREE_LOCKED(rt);
878		}
879		RADIX_NODE_HEAD_UNLOCK(rnh);
880	}
881}
882
883int
884in6_get_tmpifid(struct ifnet *ifp, u_int8_t *retbuf,
885    const u_int8_t *baseid, int generate)
886{
887	u_int8_t nullbuf[8];
888	struct nd_ifinfo *ndi = ND_IFINFO(ifp);
889
890	bzero(nullbuf, sizeof(nullbuf));
891	if (bcmp(ndi->randomid, nullbuf, sizeof(nullbuf)) == 0) {
892		/* we've never created a random ID.  Create a new one. */
893		generate = 1;
894	}
895
896	if (generate) {
897		bcopy(baseid, ndi->randomseed1, sizeof(ndi->randomseed1));
898
899		/* generate_tmp_ifid will update seedn and buf */
900		(void)generate_tmp_ifid(ndi->randomseed0, ndi->randomseed1,
901		    ndi->randomid);
902	}
903	bcopy(ndi->randomid, retbuf, 8);
904
905	return (0);
906}
907
908void
909in6_tmpaddrtimer(void *arg)
910{
911	CURVNET_SET((struct vnet *) arg);
912	struct nd_ifinfo *ndi;
913	u_int8_t nullbuf[8];
914	struct ifnet *ifp;
915
916	callout_reset(&V_in6_tmpaddrtimer_ch,
917	    (V_ip6_temp_preferred_lifetime - V_ip6_desync_factor -
918	    V_ip6_temp_regen_advance) * hz, in6_tmpaddrtimer, curvnet);
919
920	bzero(nullbuf, sizeof(nullbuf));
921	for (ifp = TAILQ_FIRST(&V_ifnet); ifp;
922	    ifp = TAILQ_NEXT(ifp, if_list)) {
923		ndi = ND_IFINFO(ifp);
924		if (bcmp(ndi->randomid, nullbuf, sizeof(nullbuf)) != 0) {
925			/*
926			 * We've been generating a random ID on this interface.
927			 * Create a new one.
928			 */
929			(void)generate_tmp_ifid(ndi->randomseed0,
930			    ndi->randomseed1, ndi->randomid);
931		}
932	}
933
934	CURVNET_RESTORE();
935}
936
937static void
938in6_purgemaddrs(struct ifnet *ifp)
939{
940	LIST_HEAD(,in6_multi)	 purgeinms;
941	struct in6_multi	*inm, *tinm;
942	struct ifmultiaddr	*ifma;
943
944	LIST_INIT(&purgeinms);
945	IN6_MULTI_LOCK();
946
947	/*
948	 * Extract list of in6_multi associated with the detaching ifp
949	 * which the PF_INET6 layer is about to release.
950	 * We need to do this as IF_ADDR_LOCK() may be re-acquired
951	 * by code further down.
952	 */
953	IF_ADDR_LOCK(ifp);
954	TAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
955		if (ifma->ifma_addr->sa_family != AF_INET6 ||
956		    ifma->ifma_protospec == NULL)
957			continue;
958		inm = (struct in6_multi *)ifma->ifma_protospec;
959		LIST_INSERT_HEAD(&purgeinms, inm, in6m_entry);
960	}
961	IF_ADDR_UNLOCK(ifp);
962
963	LIST_FOREACH_SAFE(inm, &purgeinms, in6m_entry, tinm) {
964		LIST_REMOVE(inm, in6m_entry);
965		in6m_release_locked(inm);
966	}
967	mld_ifdetach(ifp);
968
969	IN6_MULTI_UNLOCK();
970}
971