in6_ifattach.c revision 216650
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 216650 2010-12-22 11:58:31Z jhay $");
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) = 0;
71
72#ifdef IP6_AUTO_LINKLOCAL
73VNET_DEFINE(int, ip6_auto_linklocal) = IP6_AUTO_LINKLOCAL;
74#else
75VNET_DEFINE(int, ip6_auto_linklocal) = 1;	/* enabled by default */
76#endif
77
78VNET_DEFINE(struct callout, in6_tmpaddrtimer_ch);
79#define	V_in6_tmpaddrtimer_ch		VNET(in6_tmpaddrtimer_ch)
80
81VNET_DECLARE(struct inpcbinfo, ripcbinfo);
82#define	V_ripcbinfo			VNET(ripcbinfo)
83
84static int get_rand_ifid(struct ifnet *, struct in6_addr *);
85static int generate_tmp_ifid(u_int8_t *, const u_int8_t *, u_int8_t *);
86static int get_ifid(struct ifnet *, struct ifnet *, struct in6_addr *);
87static int in6_ifattach_linklocal(struct ifnet *, struct ifnet *);
88static int in6_ifattach_loopback(struct ifnet *);
89static void in6_purgemaddrs(struct ifnet *);
90
91#define EUI64_GBIT	0x01
92#define EUI64_UBIT	0x02
93#define EUI64_TO_IFID(in6)	do {(in6)->s6_addr[8] ^= EUI64_UBIT; } while (0)
94#define EUI64_GROUP(in6)	((in6)->s6_addr[8] & EUI64_GBIT)
95#define EUI64_INDIVIDUAL(in6)	(!EUI64_GROUP(in6))
96#define EUI64_LOCAL(in6)	((in6)->s6_addr[8] & EUI64_UBIT)
97#define EUI64_UNIVERSAL(in6)	(!EUI64_LOCAL(in6))
98
99#define IFID_LOCAL(in6)		(!EUI64_LOCAL(in6))
100#define IFID_UNIVERSAL(in6)	(!EUI64_UNIVERSAL(in6))
101
102/*
103 * Generate a last-resort interface identifier, when the machine has no
104 * IEEE802/EUI64 address sources.
105 * The goal here is to get an interface identifier that is
106 * (1) random enough and (2) does not change across reboot.
107 * We currently use MD5(hostname) for it.
108 *
109 * in6 - upper 64bits are preserved
110 */
111static int
112get_rand_ifid(struct ifnet *ifp, struct in6_addr *in6)
113{
114	MD5_CTX ctxt;
115	struct prison *pr;
116	u_int8_t digest[16];
117	int hostnamelen;
118
119	pr = curthread->td_ucred->cr_prison;
120	mtx_lock(&pr->pr_mtx);
121	hostnamelen = strlen(pr->pr_hostname);
122#if 0
123	/* we need at least several letters as seed for ifid */
124	if (hostnamelen < 3) {
125		mtx_unlock(&pr->pr_mtx);
126		return -1;
127	}
128#endif
129
130	/* generate 8 bytes of pseudo-random value. */
131	bzero(&ctxt, sizeof(ctxt));
132	MD5Init(&ctxt);
133	MD5Update(&ctxt, pr->pr_hostname, hostnamelen);
134	mtx_unlock(&pr->pr_mtx);
135	MD5Final(digest, &ctxt);
136
137	/* assumes sizeof(digest) > sizeof(ifid) */
138	bcopy(digest, &in6->s6_addr[8], 8);
139
140	/* make sure to set "u" bit to local, and "g" bit to individual. */
141	in6->s6_addr[8] &= ~EUI64_GBIT;	/* g bit to "individual" */
142	in6->s6_addr[8] |= EUI64_UBIT;	/* u bit to "local" */
143
144	/* convert EUI64 into IPv6 interface identifier */
145	EUI64_TO_IFID(in6);
146
147	return 0;
148}
149
150static int
151generate_tmp_ifid(u_int8_t *seed0, const u_int8_t *seed1, u_int8_t *ret)
152{
153	MD5_CTX ctxt;
154	u_int8_t seed[16], digest[16], nullbuf[8];
155	u_int32_t val32;
156
157	/* If there's no history, start with a random seed. */
158	bzero(nullbuf, sizeof(nullbuf));
159	if (bcmp(nullbuf, seed0, sizeof(nullbuf)) == 0) {
160		int i;
161
162		for (i = 0; i < 2; i++) {
163			val32 = arc4random();
164			bcopy(&val32, seed + sizeof(val32) * i, sizeof(val32));
165		}
166	} else
167		bcopy(seed0, seed, 8);
168
169	/* copy the right-most 64-bits of the given address */
170	/* XXX assumption on the size of IFID */
171	bcopy(seed1, &seed[8], 8);
172
173	if (0) {		/* for debugging purposes only */
174		int i;
175
176		printf("generate_tmp_ifid: new randomized ID from: ");
177		for (i = 0; i < 16; i++)
178			printf("%02x", seed[i]);
179		printf(" ");
180	}
181
182	/* generate 16 bytes of pseudo-random value. */
183	bzero(&ctxt, sizeof(ctxt));
184	MD5Init(&ctxt);
185	MD5Update(&ctxt, seed, sizeof(seed));
186	MD5Final(digest, &ctxt);
187
188	/*
189	 * RFC 3041 3.2.1. (3)
190	 * Take the left-most 64-bits of the MD5 digest and set bit 6 (the
191	 * left-most bit is numbered 0) to zero.
192	 */
193	bcopy(digest, ret, 8);
194	ret[0] &= ~EUI64_UBIT;
195
196	/*
197	 * XXX: we'd like to ensure that the generated value is not zero
198	 * for simplicity.  If the caclculated digest happens to be zero,
199	 * use a random non-zero value as the last resort.
200	 */
201	if (bcmp(nullbuf, ret, sizeof(nullbuf)) == 0) {
202		nd6log((LOG_INFO,
203		    "generate_tmp_ifid: computed MD5 value is zero.\n"));
204
205		val32 = arc4random();
206		val32 = 1 + (val32 % (0xffffffff - 1));
207	}
208
209	/*
210	 * RFC 3041 3.2.1. (4)
211	 * Take the rightmost 64-bits of the MD5 digest and save them in
212	 * stable storage as the history value to be used in the next
213	 * iteration of the algorithm.
214	 */
215	bcopy(&digest[8], seed0, 8);
216
217	if (0) {		/* for debugging purposes only */
218		int i;
219
220		printf("to: ");
221		for (i = 0; i < 16; i++)
222			printf("%02x", digest[i]);
223		printf("\n");
224	}
225
226	return 0;
227}
228
229/*
230 * Get interface identifier for the specified interface.
231 * XXX assumes single sockaddr_dl (AF_LINK address) per an interface
232 *
233 * in6 - upper 64bits are preserved
234 */
235int
236in6_get_hw_ifid(struct ifnet *ifp, struct in6_addr *in6)
237{
238	struct ifaddr *ifa;
239	struct sockaddr_dl *sdl;
240	u_int8_t *addr;
241	size_t addrlen;
242	static u_int8_t allzero[8] = { 0, 0, 0, 0, 0, 0, 0, 0 };
243	static u_int8_t allone[8] =
244		{ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
245
246	IF_ADDR_LOCK(ifp);
247	TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
248		if (ifa->ifa_addr->sa_family != AF_LINK)
249			continue;
250		sdl = (struct sockaddr_dl *)ifa->ifa_addr;
251		if (sdl == NULL)
252			continue;
253		if (sdl->sdl_alen == 0)
254			continue;
255
256		goto found;
257	}
258	IF_ADDR_UNLOCK(ifp);
259
260	return -1;
261
262found:
263	IF_ADDR_LOCK_ASSERT(ifp);
264	addr = LLADDR(sdl);
265	addrlen = sdl->sdl_alen;
266
267	/* get EUI64 */
268	switch (ifp->if_type) {
269	case IFT_ETHER:
270	case IFT_L2VLAN:
271	case IFT_FDDI:
272	case IFT_ISO88025:
273	case IFT_ATM:
274	case IFT_IEEE1394:
275#ifdef IFT_IEEE80211
276	case IFT_IEEE80211:
277#endif
278		/* IEEE802/EUI64 cases - what others? */
279		/* IEEE1394 uses 16byte length address starting with EUI64 */
280		if (addrlen > 8)
281			addrlen = 8;
282
283		/* look at IEEE802/EUI64 only */
284		if (addrlen != 8 && addrlen != 6) {
285			IF_ADDR_UNLOCK(ifp);
286			return -1;
287		}
288
289		/*
290		 * check for invalid MAC address - on bsdi, we see it a lot
291		 * since wildboar configures all-zero MAC on pccard before
292		 * card insertion.
293		 */
294		if (bcmp(addr, allzero, addrlen) == 0) {
295			IF_ADDR_UNLOCK(ifp);
296			return -1;
297		}
298		if (bcmp(addr, allone, addrlen) == 0) {
299			IF_ADDR_UNLOCK(ifp);
300			return -1;
301		}
302
303		/* make EUI64 address */
304		if (addrlen == 8)
305			bcopy(addr, &in6->s6_addr[8], 8);
306		else if (addrlen == 6) {
307			in6->s6_addr[8] = addr[0];
308			in6->s6_addr[9] = addr[1];
309			in6->s6_addr[10] = addr[2];
310			in6->s6_addr[11] = 0xff;
311			in6->s6_addr[12] = 0xfe;
312			in6->s6_addr[13] = addr[3];
313			in6->s6_addr[14] = addr[4];
314			in6->s6_addr[15] = addr[5];
315		}
316		break;
317
318	case IFT_ARCNET:
319		if (addrlen != 1) {
320			IF_ADDR_UNLOCK(ifp);
321			return -1;
322		}
323		if (!addr[0]) {
324			IF_ADDR_UNLOCK(ifp);
325			return -1;
326		}
327
328		bzero(&in6->s6_addr[8], 8);
329		in6->s6_addr[15] = addr[0];
330
331		/*
332		 * due to insufficient bitwidth, we mark it local.
333		 */
334		in6->s6_addr[8] &= ~EUI64_GBIT;	/* g bit to "individual" */
335		in6->s6_addr[8] |= EUI64_UBIT;	/* u bit to "local" */
336		break;
337
338	case IFT_GIF:
339#ifdef IFT_STF
340	case IFT_STF:
341#endif
342		/*
343		 * RFC2893 says: "SHOULD use IPv4 address as ifid source".
344		 * however, IPv4 address is not very suitable as unique
345		 * identifier source (can be renumbered).
346		 * we don't do this.
347		 */
348		IF_ADDR_UNLOCK(ifp);
349		return -1;
350
351	default:
352		IF_ADDR_UNLOCK(ifp);
353		return -1;
354	}
355
356	/* sanity check: g bit must not indicate "group" */
357	if (EUI64_GROUP(in6)) {
358		IF_ADDR_UNLOCK(ifp);
359		return -1;
360	}
361
362	/* convert EUI64 into IPv6 interface identifier */
363	EUI64_TO_IFID(in6);
364
365	/*
366	 * sanity check: ifid must not be all zero, avoid conflict with
367	 * subnet router anycast
368	 */
369	if ((in6->s6_addr[8] & ~(EUI64_GBIT | EUI64_UBIT)) == 0x00 &&
370	    bcmp(&in6->s6_addr[9], allzero, 7) == 0) {
371		IF_ADDR_UNLOCK(ifp);
372		return -1;
373	}
374
375	IF_ADDR_UNLOCK(ifp);
376	return 0;
377}
378
379/*
380 * Get interface identifier for the specified interface.  If it is not
381 * available on ifp0, borrow interface identifier from other information
382 * sources.
383 *
384 * altifp - secondary EUI64 source
385 */
386static int
387get_ifid(struct ifnet *ifp0, struct ifnet *altifp,
388    struct in6_addr *in6)
389{
390	struct ifnet *ifp;
391
392	/* first, try to get it from the interface itself */
393	if (in6_get_hw_ifid(ifp0, in6) == 0) {
394		nd6log((LOG_DEBUG, "%s: got interface identifier from itself\n",
395		    if_name(ifp0)));
396		goto success;
397	}
398
399	/* try secondary EUI64 source. this basically is for ATM PVC */
400	if (altifp && in6_get_hw_ifid(altifp, in6) == 0) {
401		nd6log((LOG_DEBUG, "%s: got interface identifier from %s\n",
402		    if_name(ifp0), if_name(altifp)));
403		goto success;
404	}
405
406	/* next, try to get it from some other hardware interface */
407	IFNET_RLOCK_NOSLEEP();
408	for (ifp = V_ifnet.tqh_first; ifp; ifp = ifp->if_list.tqe_next) {
409		if (ifp == ifp0)
410			continue;
411		if (in6_get_hw_ifid(ifp, in6) != 0)
412			continue;
413
414		/*
415		 * to borrow ifid from other interface, ifid needs to be
416		 * globally unique
417		 */
418		if (IFID_UNIVERSAL(in6)) {
419			nd6log((LOG_DEBUG,
420			    "%s: borrow interface identifier from %s\n",
421			    if_name(ifp0), if_name(ifp)));
422			IFNET_RUNLOCK_NOSLEEP();
423			goto success;
424		}
425	}
426	IFNET_RUNLOCK_NOSLEEP();
427
428	/* last resort: get from random number source */
429	if (get_rand_ifid(ifp, in6) == 0) {
430		nd6log((LOG_DEBUG,
431		    "%s: interface identifier generated by random number\n",
432		    if_name(ifp0)));
433		goto success;
434	}
435
436	printf("%s: failed to get interface identifier\n", if_name(ifp0));
437	return -1;
438
439success:
440	nd6log((LOG_INFO, "%s: ifid: %02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x\n",
441	    if_name(ifp0), in6->s6_addr[8], in6->s6_addr[9], in6->s6_addr[10],
442	    in6->s6_addr[11], in6->s6_addr[12], in6->s6_addr[13],
443	    in6->s6_addr[14], in6->s6_addr[15]));
444	return 0;
445}
446
447/*
448 * altifp - secondary EUI64 source
449 */
450static int
451in6_ifattach_linklocal(struct ifnet *ifp, struct ifnet *altifp)
452{
453	struct in6_ifaddr *ia;
454	struct in6_aliasreq ifra;
455	struct nd_prefixctl pr0;
456	int i, error;
457
458	/*
459	 * configure link-local address.
460	 */
461	bzero(&ifra, sizeof(ifra));
462
463	/*
464	 * in6_update_ifa() does not use ifra_name, but we accurately set it
465	 * for safety.
466	 */
467	strncpy(ifra.ifra_name, if_name(ifp), sizeof(ifra.ifra_name));
468
469	ifra.ifra_addr.sin6_family = AF_INET6;
470	ifra.ifra_addr.sin6_len = sizeof(struct sockaddr_in6);
471	ifra.ifra_addr.sin6_addr.s6_addr32[0] = htonl(0xfe800000);
472	ifra.ifra_addr.sin6_addr.s6_addr32[1] = 0;
473	if ((ifp->if_flags & IFF_LOOPBACK) != 0) {
474		ifra.ifra_addr.sin6_addr.s6_addr32[2] = 0;
475		ifra.ifra_addr.sin6_addr.s6_addr32[3] = htonl(1);
476	} else {
477		if (get_ifid(ifp, altifp, &ifra.ifra_addr.sin6_addr) != 0) {
478			nd6log((LOG_ERR,
479			    "%s: no ifid available\n", if_name(ifp)));
480			return (-1);
481		}
482	}
483	if (in6_setscope(&ifra.ifra_addr.sin6_addr, ifp, NULL))
484		return (-1);
485
486	ifra.ifra_prefixmask.sin6_len = sizeof(struct sockaddr_in6);
487	ifra.ifra_prefixmask.sin6_family = AF_INET6;
488	ifra.ifra_prefixmask.sin6_addr = in6mask64;
489	/* link-local addresses should NEVER expire. */
490	ifra.ifra_lifetime.ia6t_vltime = ND6_INFINITE_LIFETIME;
491	ifra.ifra_lifetime.ia6t_pltime = ND6_INFINITE_LIFETIME;
492
493	/*
494	 * Now call in6_update_ifa() to do a bunch of procedures to configure
495	 * a link-local address. We can set the 3rd argument to NULL, because
496	 * we know there's no other link-local address on the interface
497	 * and therefore we are adding one (instead of updating one).
498	 */
499	if ((error = in6_update_ifa(ifp, &ifra, NULL,
500				    IN6_IFAUPDATE_DADDELAY)) != 0) {
501		/*
502		 * XXX: When the interface does not support IPv6, this call
503		 * would fail in the SIOCSIFADDR ioctl.  I believe the
504		 * notification is rather confusing in this case, so just
505		 * suppress it.  (jinmei@kame.net 20010130)
506		 */
507		if (error != EAFNOSUPPORT)
508			nd6log((LOG_NOTICE, "in6_ifattach_linklocal: failed to "
509			    "configure a link-local address on %s "
510			    "(errno=%d)\n",
511			    if_name(ifp), error));
512		return (-1);
513	}
514
515	ia = in6ifa_ifpforlinklocal(ifp, 0); /* ia must not be NULL */
516#ifdef DIAGNOSTIC
517	if (!ia) {
518		panic("ia == NULL in in6_ifattach_linklocal");
519		/* NOTREACHED */
520	}
521#endif
522	ifa_free(&ia->ia_ifa);
523
524	/*
525	 * Make the link-local prefix (fe80::%link/64) as on-link.
526	 * Since we'd like to manage prefixes separately from addresses,
527	 * we make an ND6 prefix structure for the link-local prefix,
528	 * and add it to the prefix list as a never-expire prefix.
529	 * XXX: this change might affect some existing code base...
530	 */
531	bzero(&pr0, sizeof(pr0));
532	pr0.ndpr_ifp = ifp;
533	/* this should be 64 at this moment. */
534	pr0.ndpr_plen = in6_mask2len(&ifra.ifra_prefixmask.sin6_addr, NULL);
535	pr0.ndpr_prefix = ifra.ifra_addr;
536	/* apply the mask for safety. (nd6_prelist_add will apply it again) */
537	for (i = 0; i < 4; i++) {
538		pr0.ndpr_prefix.sin6_addr.s6_addr32[i] &=
539		    in6mask64.s6_addr32[i];
540	}
541	/*
542	 * Initialize parameters.  The link-local prefix must always be
543	 * on-link, and its lifetimes never expire.
544	 */
545	pr0.ndpr_raf_onlink = 1;
546	pr0.ndpr_raf_auto = 1;	/* probably meaningless */
547	pr0.ndpr_vltime = ND6_INFINITE_LIFETIME;
548	pr0.ndpr_pltime = ND6_INFINITE_LIFETIME;
549	/*
550	 * Since there is no other link-local addresses, nd6_prefix_lookup()
551	 * probably returns NULL.  However, we cannot always expect the result.
552	 * For example, if we first remove the (only) existing link-local
553	 * address, and then reconfigure another one, the prefix is still
554	 * valid with referring to the old link-local address.
555	 */
556	if (nd6_prefix_lookup(&pr0) == NULL) {
557		if ((error = nd6_prelist_add(&pr0, NULL, NULL)) != 0)
558			return (error);
559	}
560
561	return 0;
562}
563
564/*
565 * ifp - must be IFT_LOOP
566 */
567static int
568in6_ifattach_loopback(struct ifnet *ifp)
569{
570	struct in6_aliasreq ifra;
571	int error;
572
573	bzero(&ifra, sizeof(ifra));
574
575	/*
576	 * in6_update_ifa() does not use ifra_name, but we accurately set it
577	 * for safety.
578	 */
579	strncpy(ifra.ifra_name, if_name(ifp), sizeof(ifra.ifra_name));
580
581	ifra.ifra_prefixmask.sin6_len = sizeof(struct sockaddr_in6);
582	ifra.ifra_prefixmask.sin6_family = AF_INET6;
583	ifra.ifra_prefixmask.sin6_addr = in6mask128;
584
585	/*
586	 * Always initialize ia_dstaddr (= broadcast address) to loopback
587	 * address.  Follows IPv4 practice - see in_ifinit().
588	 */
589	ifra.ifra_dstaddr.sin6_len = sizeof(struct sockaddr_in6);
590	ifra.ifra_dstaddr.sin6_family = AF_INET6;
591	ifra.ifra_dstaddr.sin6_addr = in6addr_loopback;
592
593	ifra.ifra_addr.sin6_len = sizeof(struct sockaddr_in6);
594	ifra.ifra_addr.sin6_family = AF_INET6;
595	ifra.ifra_addr.sin6_addr = in6addr_loopback;
596
597	/* the loopback  address should NEVER expire. */
598	ifra.ifra_lifetime.ia6t_vltime = ND6_INFINITE_LIFETIME;
599	ifra.ifra_lifetime.ia6t_pltime = ND6_INFINITE_LIFETIME;
600
601	/* we don't need to perform DAD on loopback interfaces. */
602	ifra.ifra_flags |= IN6_IFF_NODAD;
603
604	/* skip registration to the prefix list. XXX should be temporary. */
605	ifra.ifra_flags |= IN6_IFF_NOPFX;
606
607	/*
608	 * We are sure that this is a newly assigned address, so we can set
609	 * NULL to the 3rd arg.
610	 */
611	if ((error = in6_update_ifa(ifp, &ifra, NULL, 0)) != 0) {
612		nd6log((LOG_ERR, "in6_ifattach_loopback: failed to configure "
613		    "the loopback address on %s (errno=%d)\n",
614		    if_name(ifp), error));
615		return (-1);
616	}
617
618	return 0;
619}
620
621/*
622 * compute NI group address, based on the current hostname setting.
623 * see draft-ietf-ipngwg-icmp-name-lookup-* (04 and later).
624 *
625 * when ifp == NULL, the caller is responsible for filling scopeid.
626 */
627int
628in6_nigroup(struct ifnet *ifp, const char *name, int namelen,
629    struct in6_addr *in6)
630{
631	struct prison *pr;
632	const char *p;
633	u_char *q;
634	MD5_CTX ctxt;
635	u_int8_t digest[16];
636	char l;
637	char n[64];	/* a single label must not exceed 63 chars */
638
639	/*
640	 * If no name is given and namelen is -1,
641	 * we try to do the hostname lookup ourselves.
642	 */
643	if (!name && namelen == -1) {
644		pr = curthread->td_ucred->cr_prison;
645		mtx_lock(&pr->pr_mtx);
646		name = pr->pr_hostname;
647		namelen = strlen(name);
648	} else
649		pr = NULL;
650	if (!name || !namelen) {
651		if (pr != NULL)
652			mtx_unlock(&pr->pr_mtx);
653		return -1;
654	}
655
656	p = name;
657	while (p && *p && *p != '.' && p - name < namelen)
658		p++;
659	if (p == name || p - name > sizeof(n) - 1) {
660		if (pr != NULL)
661			mtx_unlock(&pr->pr_mtx);
662		return -1;	/* label too long */
663	}
664	l = p - name;
665	strncpy(n, name, l);
666	if (pr != NULL)
667		mtx_unlock(&pr->pr_mtx);
668	n[(int)l] = '\0';
669	for (q = n; *q; q++) {
670		if ('A' <= *q && *q <= 'Z')
671			*q = *q - 'A' + 'a';
672	}
673
674	/* generate 8 bytes of pseudo-random value. */
675	bzero(&ctxt, sizeof(ctxt));
676	MD5Init(&ctxt);
677	MD5Update(&ctxt, &l, sizeof(l));
678	MD5Update(&ctxt, n, l);
679	MD5Final(digest, &ctxt);
680
681	bzero(in6, sizeof(*in6));
682	in6->s6_addr16[0] = IPV6_ADDR_INT16_MLL;
683	in6->s6_addr8[11] = 2;
684	bcopy(digest, &in6->s6_addr32[3], sizeof(in6->s6_addr32[3]));
685	if (in6_setscope(in6, ifp, NULL))
686		return (-1); /* XXX: should not fail */
687
688	return 0;
689}
690
691/*
692 * XXX multiple loopback interface needs more care.  for instance,
693 * nodelocal address needs to be configured onto only one of them.
694 * XXX multiple link-local address case
695 *
696 * altifp - secondary EUI64 source
697 */
698void
699in6_ifattach(struct ifnet *ifp, struct ifnet *altifp)
700{
701	struct in6_ifaddr *ia;
702	struct in6_addr in6;
703
704	/* some of the interfaces are inherently not IPv6 capable */
705	switch (ifp->if_type) {
706	case IFT_PFLOG:
707	case IFT_PFSYNC:
708	case IFT_CARP:
709		return;
710	}
711
712	/*
713	 * quirks based on interface type
714	 */
715	switch (ifp->if_type) {
716#ifdef IFT_STF
717	case IFT_STF:
718		/*
719		 * 6to4 interface is a very special kind of beast.
720		 * no multicast, no linklocal.  RFC2529 specifies how to make
721		 * linklocals for 6to4 interface, but there's no use and
722		 * it is rather harmful to have one.
723		 */
724		goto statinit;
725#endif
726	default:
727		break;
728	}
729
730	/*
731	 * usually, we require multicast capability to the interface
732	 */
733	if ((ifp->if_flags & IFF_MULTICAST) == 0) {
734		nd6log((LOG_INFO, "in6_ifattach: "
735		    "%s is not multicast capable, IPv6 not enabled\n",
736		    if_name(ifp)));
737		return;
738	}
739
740	/*
741	 * assign loopback address for loopback interface.
742	 * XXX multiple loopback interface case.
743	 */
744	if ((ifp->if_flags & IFF_LOOPBACK) != 0) {
745		struct ifaddr *ifa;
746
747		in6 = in6addr_loopback;
748		ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &in6);
749		if (ifa == NULL) {
750			if (in6_ifattach_loopback(ifp) != 0)
751				return;
752		} else
753			ifa_free(ifa);
754	}
755
756	/*
757	 * assign a link-local address, if there's none.
758	 */
759	if (ifp->if_type != IFT_BRIDGE &&
760	    !(ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED) &&
761	    ND_IFINFO(ifp)->flags & ND6_IFF_AUTO_LINKLOCAL) {
762		int error;
763
764		ia = in6ifa_ifpforlinklocal(ifp, 0);
765		if (ia == NULL) {
766			error = in6_ifattach_linklocal(ifp, altifp);
767#if 0
768			if (error)
769				log(LOG_NOTICE, "in6_ifattach_linklocal: "
770				    "failed to add a link-local addr to %s\n",
771				    if_name(ifp));
772#endif
773		} else
774			ifa_free(&ia->ia_ifa);
775	}
776
777#ifdef IFT_STF			/* XXX */
778statinit:
779#endif
780
781	/* update dynamically. */
782	if (V_in6_maxmtu < ifp->if_mtu)
783		V_in6_maxmtu = ifp->if_mtu;
784}
785
786/*
787 * NOTE: in6_ifdetach() does not support loopback if at this moment.
788 * We don't need this function in bsdi, because interfaces are never removed
789 * from the ifnet list in bsdi.
790 */
791void
792in6_ifdetach(struct ifnet *ifp)
793{
794	struct in6_ifaddr *ia;
795	struct ifaddr *ifa, *next;
796	struct radix_node_head *rnh;
797	struct rtentry *rt;
798	short rtflags;
799	struct sockaddr_in6 sin6;
800	struct in6_multi_mship *imm;
801
802	/* remove neighbor management table */
803	nd6_purge(ifp);
804
805	/* nuke any of IPv6 addresses we have */
806	TAILQ_FOREACH_SAFE(ifa, &ifp->if_addrhead, ifa_link, next) {
807		if (ifa->ifa_addr->sa_family != AF_INET6)
808			continue;
809		in6_purgeaddr(ifa);
810	}
811
812	/* undo everything done by in6_ifattach(), just in case */
813	TAILQ_FOREACH_SAFE(ifa, &ifp->if_addrhead, ifa_link, next) {
814		if (ifa->ifa_addr->sa_family != AF_INET6
815		 || !IN6_IS_ADDR_LINKLOCAL(&satosin6(&ifa->ifa_addr)->sin6_addr)) {
816			continue;
817		}
818
819		ia = (struct in6_ifaddr *)ifa;
820
821		/*
822		 * leave from multicast groups we have joined for the interface
823		 */
824		while ((imm = ia->ia6_memberships.lh_first) != NULL) {
825			LIST_REMOVE(imm, i6mm_chain);
826			in6_leavegroup(imm);
827		}
828
829		/* remove from the routing table */
830		if ((ia->ia_flags & IFA_ROUTE) &&
831		    (rt = rtalloc1((struct sockaddr *)&ia->ia_addr, 0, 0UL))) {
832			rtflags = rt->rt_flags;
833			RTFREE_LOCKED(rt);
834			rtrequest(RTM_DELETE, (struct sockaddr *)&ia->ia_addr,
835			    (struct sockaddr *)&ia->ia_addr,
836			    (struct sockaddr *)&ia->ia_prefixmask,
837			    rtflags, (struct rtentry **)0);
838		}
839
840		/* remove from the linked list */
841		IF_ADDR_LOCK(ifp);
842		TAILQ_REMOVE(&ifp->if_addrhead, ifa, ifa_link);
843		IF_ADDR_UNLOCK(ifp);
844		ifa_free(ifa);				/* if_addrhead */
845
846		IN6_IFADDR_WLOCK();
847		TAILQ_REMOVE(&V_in6_ifaddrhead, ia, ia_link);
848		IN6_IFADDR_WUNLOCK();
849		ifa_free(ifa);
850	}
851
852	in6_pcbpurgeif0(&V_udbinfo, ifp);
853	in6_pcbpurgeif0(&V_ripcbinfo, ifp);
854	/* leave from all multicast groups joined */
855	in6_purgemaddrs(ifp);
856
857	/*
858	 * remove neighbor management table.  we call it twice just to make
859	 * sure we nuke everything.  maybe we need just one call.
860	 * XXX: since the first call did not release addresses, some prefixes
861	 * might remain.  We should call nd6_purge() again to release the
862	 * prefixes after removing all addresses above.
863	 * (Or can we just delay calling nd6_purge until at this point?)
864	 */
865	nd6_purge(ifp);
866
867	/* remove route to link-local allnodes multicast (ff02::1) */
868	bzero(&sin6, sizeof(sin6));
869	sin6.sin6_len = sizeof(struct sockaddr_in6);
870	sin6.sin6_family = AF_INET6;
871	sin6.sin6_addr = in6addr_linklocal_allnodes;
872	if (in6_setscope(&sin6.sin6_addr, ifp, NULL))
873		/* XXX: should not fail */
874		return;
875	/* XXX grab lock first to avoid LOR */
876	rnh = rt_tables_get_rnh(0, AF_INET6);
877	if (rnh != NULL) {
878		RADIX_NODE_HEAD_LOCK(rnh);
879		rt = rtalloc1((struct sockaddr *)&sin6, 0, RTF_RNH_LOCKED);
880		if (rt) {
881			if (rt->rt_ifp == ifp)
882				rtexpunge(rt);
883			RTFREE_LOCKED(rt);
884		}
885		RADIX_NODE_HEAD_UNLOCK(rnh);
886	}
887}
888
889int
890in6_get_tmpifid(struct ifnet *ifp, u_int8_t *retbuf,
891    const u_int8_t *baseid, int generate)
892{
893	u_int8_t nullbuf[8];
894	struct nd_ifinfo *ndi = ND_IFINFO(ifp);
895
896	bzero(nullbuf, sizeof(nullbuf));
897	if (bcmp(ndi->randomid, nullbuf, sizeof(nullbuf)) == 0) {
898		/* we've never created a random ID.  Create a new one. */
899		generate = 1;
900	}
901
902	if (generate) {
903		bcopy(baseid, ndi->randomseed1, sizeof(ndi->randomseed1));
904
905		/* generate_tmp_ifid will update seedn and buf */
906		(void)generate_tmp_ifid(ndi->randomseed0, ndi->randomseed1,
907		    ndi->randomid);
908	}
909	bcopy(ndi->randomid, retbuf, 8);
910
911	return (0);
912}
913
914void
915in6_tmpaddrtimer(void *arg)
916{
917	CURVNET_SET((struct vnet *) arg);
918	struct nd_ifinfo *ndi;
919	u_int8_t nullbuf[8];
920	struct ifnet *ifp;
921
922	callout_reset(&V_in6_tmpaddrtimer_ch,
923	    (V_ip6_temp_preferred_lifetime - V_ip6_desync_factor -
924	    V_ip6_temp_regen_advance) * hz, in6_tmpaddrtimer, curvnet);
925
926	bzero(nullbuf, sizeof(nullbuf));
927	for (ifp = TAILQ_FIRST(&V_ifnet); ifp;
928	    ifp = TAILQ_NEXT(ifp, if_list)) {
929		ndi = ND_IFINFO(ifp);
930		if (bcmp(ndi->randomid, nullbuf, sizeof(nullbuf)) != 0) {
931			/*
932			 * We've been generating a random ID on this interface.
933			 * Create a new one.
934			 */
935			(void)generate_tmp_ifid(ndi->randomseed0,
936			    ndi->randomseed1, ndi->randomid);
937		}
938	}
939
940	CURVNET_RESTORE();
941}
942
943static void
944in6_purgemaddrs(struct ifnet *ifp)
945{
946	LIST_HEAD(,in6_multi)	 purgeinms;
947	struct in6_multi	*inm, *tinm;
948	struct ifmultiaddr	*ifma;
949
950	LIST_INIT(&purgeinms);
951	IN6_MULTI_LOCK();
952
953	/*
954	 * Extract list of in6_multi associated with the detaching ifp
955	 * which the PF_INET6 layer is about to release.
956	 * We need to do this as IF_ADDR_LOCK() may be re-acquired
957	 * by code further down.
958	 */
959	IF_ADDR_LOCK(ifp);
960	TAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
961		if (ifma->ifma_addr->sa_family != AF_INET6 ||
962		    ifma->ifma_protospec == NULL)
963			continue;
964		inm = (struct in6_multi *)ifma->ifma_protospec;
965		LIST_INSERT_HEAD(&purgeinms, inm, in6m_entry);
966	}
967	IF_ADDR_UNLOCK(ifp);
968
969	LIST_FOREACH_SAFE(inm, &purgeinms, in6m_entry, tinm) {
970		LIST_REMOVE(inm, in6m_entry);
971		in6m_release_locked(inm);
972	}
973	mld_ifdetach(ifp);
974
975	IN6_MULTI_UNLOCK();
976}
977