xref: /freebsd/sys/netinet6/in6_ifattach.c (revision 0daa334c56334661ec68a514a95fa1d92c483e8e)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the project nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  *
31  *	$KAME: in6_ifattach.c,v 1.118 2001/05/24 07:44:00 itojun Exp $
32  */
33 
34 #include <sys/param.h>
35 #include <sys/systm.h>
36 #include <sys/malloc.h>
37 #include <sys/socket.h>
38 #include <sys/sockio.h>
39 #include <sys/jail.h>
40 #include <sys/kernel.h>
41 #include <sys/lock.h>
42 #include <sys/proc.h>
43 #include <sys/rmlock.h>
44 #include <sys/syslog.h>
45 #include <sys/md5.h>
46 
47 #include <net/if.h>
48 #include <net/if_var.h>
49 #include <net/if_dl.h>
50 #include <net/if_private.h>
51 #include <net/if_types.h>
52 #include <net/route.h>
53 #include <net/vnet.h>
54 
55 #include <netinet/in.h>
56 #include <netinet/in_var.h>
57 #include <netinet/if_ether.h>
58 #include <netinet/in_pcb.h>
59 #include <netinet/ip_var.h>
60 #include <netinet/udp.h>
61 #include <netinet/udp_var.h>
62 
63 #include <netinet/ip6.h>
64 #include <netinet6/ip6_var.h>
65 #include <netinet6/in6_var.h>
66 #include <netinet6/in6_pcb.h>
67 #include <netinet6/in6_ifattach.h>
68 #include <netinet6/ip6_var.h>
69 #include <netinet6/nd6.h>
70 #include <netinet6/mld6_var.h>
71 #include <netinet6/scope6_var.h>
72 
73 #ifdef IP6_AUTO_LINKLOCAL
74 VNET_DEFINE(int, ip6_auto_linklocal) = IP6_AUTO_LINKLOCAL;
75 #else
76 VNET_DEFINE(int, ip6_auto_linklocal) = 1;	/* enabled by default */
77 #endif
78 
79 VNET_DEFINE(struct callout, in6_tmpaddrtimer_ch);
80 #define	V_in6_tmpaddrtimer_ch		VNET(in6_tmpaddrtimer_ch)
81 
82 VNET_DECLARE(struct inpcbinfo, ripcbinfo);
83 #define	V_ripcbinfo			VNET(ripcbinfo)
84 
85 static int get_rand_ifid(struct ifnet *, struct in6_addr *);
86 static int get_ifid(struct ifnet *, struct ifnet *, struct in6_addr *);
87 static int in6_ifattach_linklocal(struct ifnet *, struct ifnet *);
88 static int in6_ifattach_loopback(struct ifnet *);
89 static 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  */
111 static int
get_rand_ifid(struct ifnet * ifp,struct in6_addr * in6)112 get_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 
150 
151 /*
152  * Get interface identifier for the specified interface.
153  * XXX assumes single sockaddr_dl (AF_LINK address) per an interface
154  *
155  * in6 - upper 64bits are preserved
156  */
157 int
in6_get_hw_ifid(struct ifnet * ifp,struct in6_addr * in6)158 in6_get_hw_ifid(struct ifnet *ifp, struct in6_addr *in6)
159 {
160 	struct ifaddr *ifa;
161 	struct sockaddr_dl *sdl;
162 	u_int8_t *addr;
163 	size_t addrlen;
164 	static u_int8_t allzero[8] = { 0, 0, 0, 0, 0, 0, 0, 0 };
165 	static u_int8_t allone[8] =
166 		{ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
167 
168 	NET_EPOCH_ASSERT();
169 
170 	CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
171 		if (ifa->ifa_addr->sa_family != AF_LINK)
172 			continue;
173 		sdl = (struct sockaddr_dl *)ifa->ifa_addr;
174 		if (sdl == NULL)
175 			continue;
176 		if (sdl->sdl_alen == 0)
177 			continue;
178 
179 		goto found;
180 	}
181 
182 	return -1;
183 
184 found:
185 	addr = LLADDR(sdl);
186 	addrlen = sdl->sdl_alen;
187 
188 	/* get EUI64 */
189 	switch (ifp->if_type) {
190 	case IFT_BRIDGE:
191 	case IFT_ETHER:
192 	case IFT_L2VLAN:
193 	case IFT_ATM:
194 	case IFT_IEEE1394:
195 		/* IEEE802/EUI64 cases - what others? */
196 		/* IEEE1394 uses 16byte length address starting with EUI64 */
197 		if (addrlen > 8)
198 			addrlen = 8;
199 
200 		/* look at IEEE802/EUI64 only */
201 		if (addrlen != 8 && addrlen != 6)
202 			return -1;
203 
204 		/*
205 		 * check for invalid MAC address - on bsdi, we see it a lot
206 		 * since wildboar configures all-zero MAC on pccard before
207 		 * card insertion.
208 		 */
209 		if (bcmp(addr, allzero, addrlen) == 0)
210 			return -1;
211 		if (bcmp(addr, allone, addrlen) == 0)
212 			return -1;
213 
214 		/* make EUI64 address */
215 		if (addrlen == 8)
216 			bcopy(addr, &in6->s6_addr[8], 8);
217 		else if (addrlen == 6) {
218 			in6->s6_addr[8] = addr[0];
219 			in6->s6_addr[9] = addr[1];
220 			in6->s6_addr[10] = addr[2];
221 			in6->s6_addr[11] = 0xff;
222 			in6->s6_addr[12] = 0xfe;
223 			in6->s6_addr[13] = addr[3];
224 			in6->s6_addr[14] = addr[4];
225 			in6->s6_addr[15] = addr[5];
226 		}
227 		break;
228 
229 	case IFT_GIF:
230 	case IFT_STF:
231 		/*
232 		 * RFC2893 says: "SHOULD use IPv4 address as ifid source".
233 		 * however, IPv4 address is not very suitable as unique
234 		 * identifier source (can be renumbered).
235 		 * we don't do this.
236 		 */
237 		return -1;
238 
239 	case IFT_INFINIBAND:
240 		if (addrlen != 20)
241 			return -1;
242 		bcopy(addr + 12, &in6->s6_addr[8], 8);
243 		break;
244 
245 	default:
246 		return -1;
247 	}
248 
249 	/* sanity check: g bit must not indicate "group" */
250 	if (EUI64_GROUP(in6))
251 		return -1;
252 
253 	/* convert EUI64 into IPv6 interface identifier */
254 	EUI64_TO_IFID(in6);
255 
256 	/*
257 	 * sanity check: ifid must not be all zero, avoid conflict with
258 	 * subnet router anycast
259 	 */
260 	if ((in6->s6_addr[8] & ~(EUI64_GBIT | EUI64_UBIT)) == 0x00 &&
261 	    bcmp(&in6->s6_addr[9], allzero, 7) == 0)
262 		return -1;
263 
264 	return 0;
265 }
266 
267 /*
268  * Get interface identifier for the specified interface.  If it is not
269  * available on ifp0, borrow interface identifier from other information
270  * sources.
271  *
272  * altifp - secondary EUI64 source
273  */
274 static int
get_ifid(struct ifnet * ifp0,struct ifnet * altifp,struct in6_addr * in6)275 get_ifid(struct ifnet *ifp0, struct ifnet *altifp,
276     struct in6_addr *in6)
277 {
278 	struct ifnet *ifp;
279 
280 	NET_EPOCH_ASSERT();
281 
282 	/* first, try to get it from the interface itself */
283 	if (in6_get_hw_ifid(ifp0, in6) == 0) {
284 		nd6log((LOG_DEBUG, "%s: got interface identifier from itself\n",
285 		    if_name(ifp0)));
286 		goto success;
287 	}
288 
289 	/* try secondary EUI64 source. this basically is for ATM PVC */
290 	if (altifp && in6_get_hw_ifid(altifp, in6) == 0) {
291 		nd6log((LOG_DEBUG, "%s: got interface identifier from %s\n",
292 		    if_name(ifp0), if_name(altifp)));
293 		goto success;
294 	}
295 
296 	/* next, try to get it from some other hardware interface */
297 	CK_STAILQ_FOREACH(ifp, &V_ifnet, if_link) {
298 		if (ifp == ifp0)
299 			continue;
300 		if (in6_get_hw_ifid(ifp, in6) != 0)
301 			continue;
302 
303 		/*
304 		 * to borrow ifid from other interface, ifid needs to be
305 		 * globally unique
306 		 */
307 		if (IFID_UNIVERSAL(in6)) {
308 			nd6log((LOG_DEBUG,
309 			    "%s: borrow interface identifier from %s\n",
310 			    if_name(ifp0), if_name(ifp)));
311 			goto success;
312 		}
313 	}
314 
315 	/* last resort: get from random number source */
316 	if (get_rand_ifid(ifp, in6) == 0) {
317 		nd6log((LOG_DEBUG,
318 		    "%s: interface identifier generated by random number\n",
319 		    if_name(ifp0)));
320 		goto success;
321 	}
322 
323 	printf("%s: failed to get interface identifier\n", if_name(ifp0));
324 	return -1;
325 
326 success:
327 	nd6log((LOG_INFO, "%s: ifid: %02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x\n",
328 	    if_name(ifp0), in6->s6_addr[8], in6->s6_addr[9], in6->s6_addr[10],
329 	    in6->s6_addr[11], in6->s6_addr[12], in6->s6_addr[13],
330 	    in6->s6_addr[14], in6->s6_addr[15]));
331 	return 0;
332 }
333 
334 /*
335  * altifp - secondary EUI64 source
336  */
337 static int
in6_ifattach_linklocal(struct ifnet * ifp,struct ifnet * altifp)338 in6_ifattach_linklocal(struct ifnet *ifp, struct ifnet *altifp)
339 {
340 	struct in6_ifaddr *ia;
341 	struct in6_aliasreq ifra;
342 	struct nd_prefixctl pr0;
343 	struct epoch_tracker et;
344 	struct nd_prefix *pr;
345 	int error;
346 
347 	/*
348 	 * configure link-local address.
349 	 */
350 	in6_prepare_ifra(&ifra, NULL, &in6mask64);
351 
352 	ifra.ifra_addr.sin6_addr.s6_addr32[0] = htonl(0xfe800000);
353 	ifra.ifra_addr.sin6_addr.s6_addr32[1] = 0;
354 	if ((ifp->if_flags & IFF_LOOPBACK) != 0) {
355 		ifra.ifra_addr.sin6_addr.s6_addr32[2] = 0;
356 		ifra.ifra_addr.sin6_addr.s6_addr32[3] = htonl(1);
357 	} else {
358 		NET_EPOCH_ENTER(et);
359 		error = get_ifid(ifp, altifp, &ifra.ifra_addr.sin6_addr);
360 		NET_EPOCH_EXIT(et);
361 		if (error != 0) {
362 			nd6log((LOG_ERR,
363 			    "%s: no ifid available\n", if_name(ifp)));
364 			return (-1);
365 		}
366 	}
367 	if (in6_setscope(&ifra.ifra_addr.sin6_addr, ifp, NULL))
368 		return (-1);
369 
370 	/* link-local addresses should NEVER expire. */
371 	ifra.ifra_lifetime.ia6t_vltime = ND6_INFINITE_LIFETIME;
372 	ifra.ifra_lifetime.ia6t_pltime = ND6_INFINITE_LIFETIME;
373 
374 	/*
375 	 * Now call in6_update_ifa() to do a bunch of procedures to configure
376 	 * a link-local address. We can set the 3rd argument to NULL, because
377 	 * we know there's no other link-local address on the interface
378 	 * and therefore we are adding one (instead of updating one).
379 	 */
380 	if ((error = in6_update_ifa(ifp, &ifra, NULL,
381 				    IN6_IFAUPDATE_DADDELAY)) != 0) {
382 		/*
383 		 * XXX: When the interface does not support IPv6, this call
384 		 * would fail in the SIOCSIFADDR ioctl.  I believe the
385 		 * notification is rather confusing in this case, so just
386 		 * suppress it.  (jinmei@kame.net 20010130)
387 		 */
388 		if (error != EAFNOSUPPORT)
389 			nd6log((LOG_NOTICE, "in6_ifattach_linklocal: failed to "
390 			    "configure a link-local address on %s "
391 			    "(errno=%d)\n",
392 			    if_name(ifp), error));
393 		return (-1);
394 	}
395 
396 	NET_EPOCH_ENTER(et);
397 	ia = in6ifa_ifpforlinklocal(ifp, 0);
398 	NET_EPOCH_EXIT(et);
399 	if (ia == NULL) {
400 		/*
401 		 * Another thread removed the address that we just added.
402 		 * This should be rare, but it happens.
403 		 */
404 		nd6log((LOG_NOTICE, "%s: %s: new link-local address "
405 			"disappeared\n", __func__, if_name(ifp)));
406 		return (-1);
407 	}
408 	ifa_free(&ia->ia_ifa);
409 
410 	/*
411 	 * Make the link-local prefix (fe80::%link/64) as on-link.
412 	 * Since we'd like to manage prefixes separately from addresses,
413 	 * we make an ND6 prefix structure for the link-local prefix,
414 	 * and add it to the prefix list as a never-expire prefix.
415 	 * XXX: this change might affect some existing code base...
416 	 */
417 	bzero(&pr0, sizeof(pr0));
418 	pr0.ndpr_ifp = ifp;
419 	/* this should be 64 at this moment. */
420 	pr0.ndpr_plen = in6_mask2len(&ifra.ifra_prefixmask.sin6_addr, NULL);
421 	pr0.ndpr_prefix = ifra.ifra_addr;
422 	/* apply the mask for safety. (nd6_prelist_add will apply it again) */
423 	IN6_MASK_ADDR(&pr0.ndpr_prefix.sin6_addr, &in6mask64);
424 	/*
425 	 * Initialize parameters.  The link-local prefix must always be
426 	 * on-link, and its lifetimes never expire.
427 	 */
428 	pr0.ndpr_raf_onlink = 1;
429 	pr0.ndpr_raf_auto = 1;	/* probably meaningless */
430 	pr0.ndpr_vltime = ND6_INFINITE_LIFETIME;
431 	pr0.ndpr_pltime = ND6_INFINITE_LIFETIME;
432 	/*
433 	 * Since there is no other link-local addresses, nd6_prefix_lookup()
434 	 * probably returns NULL.  However, we cannot always expect the result.
435 	 * For example, if we first remove the (only) existing link-local
436 	 * address, and then reconfigure another one, the prefix is still
437 	 * valid with referring to the old link-local address.
438 	 */
439 	if ((pr = nd6_prefix_lookup(&pr0)) == NULL) {
440 		if ((error = nd6_prelist_add(&pr0, NULL, &pr)) != 0)
441 			return (error);
442 		/* Reference prefix */
443 		ia->ia6_ndpr = pr;
444 		pr->ndpr_addrcnt++;
445 	} else
446 		nd6_prefix_rele(pr);
447 
448 	return 0;
449 }
450 
451 /*
452  * ifp - must be IFT_LOOP
453  */
454 static int
in6_ifattach_loopback(struct ifnet * ifp)455 in6_ifattach_loopback(struct ifnet *ifp)
456 {
457 	struct in6_aliasreq ifra;
458 	int error;
459 
460 	in6_prepare_ifra(&ifra, &in6addr_loopback, &in6mask128);
461 
462 	/*
463 	 * Always initialize ia_dstaddr (= broadcast address) to loopback
464 	 * address.  Follows IPv4 practice - see in_ifinit().
465 	 */
466 	ifra.ifra_dstaddr.sin6_len = sizeof(struct sockaddr_in6);
467 	ifra.ifra_dstaddr.sin6_family = AF_INET6;
468 	ifra.ifra_dstaddr.sin6_addr = in6addr_loopback;
469 
470 	/* the loopback  address should NEVER expire. */
471 	ifra.ifra_lifetime.ia6t_vltime = ND6_INFINITE_LIFETIME;
472 	ifra.ifra_lifetime.ia6t_pltime = ND6_INFINITE_LIFETIME;
473 
474 	/*
475 	 * We are sure that this is a newly assigned address, so we can set
476 	 * NULL to the 3rd arg.
477 	 */
478 	if ((error = in6_update_ifa(ifp, &ifra, NULL, 0)) != 0) {
479 		nd6log((LOG_ERR, "in6_ifattach_loopback: failed to configure "
480 		    "the loopback address on %s (errno=%d)\n",
481 		    if_name(ifp), error));
482 		return (-1);
483 	}
484 
485 	return 0;
486 }
487 
488 /*
489  * compute NI group address, based on the current hostname setting.
490  * see RFC 4620.
491  *
492  * when ifp == NULL, the caller is responsible for filling scopeid.
493  *
494  * If oldmcprefix == 1, FF02:0:0:0:0:2::/96 is used for NI group address
495  * while it is FF02:0:0:0:0:2:FF00::/104 in RFC 4620.
496  */
497 static int
in6_nigroup0(struct ifnet * ifp,const char * name,int namelen,struct in6_addr * in6,int oldmcprefix)498 in6_nigroup0(struct ifnet *ifp, const char *name, int namelen,
499     struct in6_addr *in6, int oldmcprefix)
500 {
501 	struct prison *pr;
502 	const char *p;
503 	u_char *q;
504 	MD5_CTX ctxt;
505 	u_int8_t digest[16];
506 	char l;
507 	char n[64];	/* a single label must not exceed 63 chars */
508 
509 	/*
510 	 * If no name is given and namelen is -1,
511 	 * we try to do the hostname lookup ourselves.
512 	 */
513 	if (!name && namelen == -1) {
514 		pr = curthread->td_ucred->cr_prison;
515 		mtx_lock(&pr->pr_mtx);
516 		name = pr->pr_hostname;
517 		namelen = strlen(name);
518 	} else
519 		pr = NULL;
520 	if (!name || !namelen) {
521 		if (pr != NULL)
522 			mtx_unlock(&pr->pr_mtx);
523 		return -1;
524 	}
525 
526 	p = name;
527 	while (p && *p && *p != '.' && p - name < namelen)
528 		p++;
529 	if (p == name || p - name > sizeof(n) - 1) {
530 		if (pr != NULL)
531 			mtx_unlock(&pr->pr_mtx);
532 		return -1;	/* label too long */
533 	}
534 	l = p - name;
535 	strncpy(n, name, l);
536 	if (pr != NULL)
537 		mtx_unlock(&pr->pr_mtx);
538 	n[(int)l] = '\0';
539 	for (q = n; *q; q++) {
540 		if ('A' <= *q && *q <= 'Z')
541 			*q = *q - 'A' + 'a';
542 	}
543 
544 	/* generate 16 bytes of pseudo-random value. */
545 	bzero(&ctxt, sizeof(ctxt));
546 	MD5Init(&ctxt);
547 	MD5Update(&ctxt, &l, sizeof(l));
548 	MD5Update(&ctxt, n, l);
549 	MD5Final(digest, &ctxt);
550 
551 	bzero(in6, sizeof(*in6));
552 	in6->s6_addr16[0] = IPV6_ADDR_INT16_MLL;
553 	in6->s6_addr8[11] = 2;
554 	if (oldmcprefix == 0) {
555 		in6->s6_addr8[12] = 0xff;
556 	 	/* Copy the first 24 bits of 128-bit hash into the address. */
557 		bcopy(digest, &in6->s6_addr8[13], 3);
558 	} else {
559 	 	/* Copy the first 32 bits of 128-bit hash into the address. */
560 		bcopy(digest, &in6->s6_addr32[3], sizeof(in6->s6_addr32[3]));
561 	}
562 	if (in6_setscope(in6, ifp, NULL))
563 		return (-1); /* XXX: should not fail */
564 
565 	return 0;
566 }
567 
568 int
in6_nigroup(struct ifnet * ifp,const char * name,int namelen,struct in6_addr * in6)569 in6_nigroup(struct ifnet *ifp, const char *name, int namelen,
570     struct in6_addr *in6)
571 {
572 
573 	return (in6_nigroup0(ifp, name, namelen, in6, 0));
574 }
575 
576 int
in6_nigroup_oldmcprefix(struct ifnet * ifp,const char * name,int namelen,struct in6_addr * in6)577 in6_nigroup_oldmcprefix(struct ifnet *ifp, const char *name, int namelen,
578     struct in6_addr *in6)
579 {
580 
581 	return (in6_nigroup0(ifp, name, namelen, in6, 1));
582 }
583 
584 /*
585  * XXX multiple loopback interface needs more care.  for instance,
586  * nodelocal address needs to be configured onto only one of them.
587  * XXX multiple link-local address case
588  *
589  * altifp - secondary EUI64 source
590  */
591 void
in6_ifattach(struct ifnet * ifp,struct ifnet * altifp)592 in6_ifattach(struct ifnet *ifp, struct ifnet *altifp)
593 {
594 	struct in6_ifaddr *ia;
595 
596 	if (ifp->if_afdata[AF_INET6] == NULL)
597 		return;
598 	/*
599 	 * quirks based on interface type
600 	 */
601 	switch (ifp->if_type) {
602 	case IFT_STF:
603 		/*
604 		 * 6to4 interface is a very special kind of beast.
605 		 * no multicast, no linklocal.  RFC2529 specifies how to make
606 		 * linklocals for 6to4 interface, but there's no use and
607 		 * it is rather harmful to have one.
608 		 */
609 		ND_IFINFO(ifp)->flags &= ~ND6_IFF_AUTO_LINKLOCAL;
610 		ND_IFINFO(ifp)->flags |= ND6_IFF_NO_DAD;
611 		break;
612 	default:
613 		break;
614 	}
615 
616 	/*
617 	 * usually, we require multicast capability to the interface
618 	 */
619 	if ((ifp->if_flags & IFF_MULTICAST) == 0) {
620 		nd6log((LOG_INFO, "in6_ifattach: "
621 		    "%s is not multicast capable, IPv6 not enabled\n",
622 		    if_name(ifp)));
623 		return;
624 	}
625 
626 	/*
627 	 * assign loopback address for loopback interface.
628 	 */
629 	if ((ifp->if_flags & IFF_LOOPBACK) != 0) {
630 		/*
631 		 * check that loopback address doesn't exist yet.
632 		 */
633 		ia = in6ifa_ifwithaddr(&in6addr_loopback, 0, false);
634 		if (ia == NULL)
635 			in6_ifattach_loopback(ifp);
636 	}
637 
638 	/*
639 	 * assign a link-local address, if there's none.
640 	 */
641 	if (!(ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED) &&
642 	    ND_IFINFO(ifp)->flags & ND6_IFF_AUTO_LINKLOCAL) {
643 		struct epoch_tracker et;
644 
645 		NET_EPOCH_ENTER(et);
646 		ia = in6ifa_ifpforlinklocal(ifp, 0);
647 		NET_EPOCH_EXIT(et);
648 		if (ia == NULL)
649 			in6_ifattach_linklocal(ifp, altifp);
650 		else
651 			ifa_free(&ia->ia_ifa);
652 	}
653 }
654 
655 /*
656  * NOTE: in6_ifdetach() does not support loopback if at this moment.
657  *
658  * When shutting down a VNET we clean up layers top-down.  In that case
659  * upper layer protocols (ulp) are cleaned up already and locks are destroyed
660  * and we must not call into these cleanup functions anymore, thus purgeulp
661  * is set to 0 in that case by in6_ifdetach_destroy().
662  * The normal case of destroying a (cloned) interface still needs to cleanup
663  * everything related to the interface and will have purgeulp set to 1.
664  */
665 static void
_in6_ifdetach(struct ifnet * ifp,int purgeulp)666 _in6_ifdetach(struct ifnet *ifp, int purgeulp)
667 {
668 	struct ifaddr *ifa, *next;
669 
670 	if (ifp->if_afdata[AF_INET6] == NULL)
671 		return;
672 
673 	/*
674 	 * nuke any of IPv6 addresses we have
675 	 */
676 	CK_STAILQ_FOREACH_SAFE(ifa, &ifp->if_addrhead, ifa_link, next) {
677 		if (ifa->ifa_addr->sa_family != AF_INET6)
678 			continue;
679 		in6_purgeaddr(ifa);
680 	}
681 	if (purgeulp) {
682 		IN6_MULTI_LOCK();
683 		in6_pcbpurgeif0(&V_udbinfo, ifp);
684 		in6_pcbpurgeif0(&V_ulitecbinfo, ifp);
685 		in6_pcbpurgeif0(&V_ripcbinfo, ifp);
686 		IN6_MULTI_UNLOCK();
687 	}
688 	/* leave from all multicast groups joined */
689 	in6_purgemaddrs(ifp);
690 
691 	/*
692 	 * Remove neighbor management table.
693 	 * Enabling the nd6_purge will panic on vmove for interfaces on VNET
694 	 * teardown as the IPv6 layer is cleaned up already and the locks
695 	 * are destroyed.
696 	 */
697 	if (purgeulp)
698 		nd6_purge(ifp);
699 }
700 
701 void
in6_ifdetach(struct ifnet * ifp)702 in6_ifdetach(struct ifnet *ifp)
703 {
704 
705 	_in6_ifdetach(ifp, 1);
706 }
707 
708 void
in6_ifdetach_destroy(struct ifnet * ifp)709 in6_ifdetach_destroy(struct ifnet *ifp)
710 {
711 
712 	_in6_ifdetach(ifp, 0);
713 }
714 
715 void
in6_tmpaddrtimer(void * arg)716 in6_tmpaddrtimer(void *arg)
717 {
718 	CURVNET_SET((struct vnet *) arg);
719 
720 	callout_reset(&V_in6_tmpaddrtimer_ch,
721 	    (V_ip6_temp_preferred_lifetime - V_ip6_desync_factor -
722 	    V_ip6_temp_regen_advance) * hz, in6_tmpaddrtimer, curvnet);
723 
724 	CURVNET_RESTORE();
725 }
726 
727 static void
in6_purgemaddrs(struct ifnet * ifp)728 in6_purgemaddrs(struct ifnet *ifp)
729 {
730 	struct in6_multi_head inmh;
731 
732 	SLIST_INIT(&inmh);
733 	IN6_MULTI_LOCK();
734 	IN6_MULTI_LIST_LOCK();
735 	mld_ifdetach(ifp, &inmh);
736 	IN6_MULTI_LIST_UNLOCK();
737 	IN6_MULTI_UNLOCK();
738 	in6m_release_list_deferred(&inmh);
739 
740 	/*
741 	 * Make sure all multicast deletions invoking if_ioctl() are
742 	 * completed before returning. Else we risk accessing a freed
743 	 * ifnet structure pointer.
744 	 */
745 	in6m_release_wait(NULL);
746 }
747 
748 void
in6_ifattach_destroy(void)749 in6_ifattach_destroy(void)
750 {
751 
752 	callout_drain(&V_in6_tmpaddrtimer_ch);
753 }
754 
755 static void
in6_ifattach_init(void * dummy)756 in6_ifattach_init(void *dummy)
757 {
758 
759 	/* Timer for regeneranation of temporary addresses randomize ID. */
760 	callout_init(&V_in6_tmpaddrtimer_ch, 1);
761 	callout_reset(&V_in6_tmpaddrtimer_ch,
762 	    (V_ip6_temp_preferred_lifetime - V_ip6_desync_factor -
763 	    V_ip6_temp_regen_advance) * hz,
764 	    in6_tmpaddrtimer, curvnet);
765 }
766 
767 /*
768  * Cheat.
769  * This must be after route_init(), which is now SI_ORDER_THIRD.
770  */
771 SYSINIT(in6_ifattach_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_MIDDLE,
772     in6_ifattach_init, NULL);
773