xref: /dflybsd-src/sys/net/if.c (revision 23c32883e759b0ea42fdaff39e661bd1a12e3b9f)
1 /*
2  * Copyright (c) 1980, 1986, 1993
3  *	The Regents of the University of California.  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. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  *	@(#)if.c	8.3 (Berkeley) 1/4/94
34  * $FreeBSD: src/sys/net/if.c,v 1.185 2004/03/13 02:35:03 brooks Exp $
35  * $DragonFly: src/sys/net/if.c,v 1.30 2005/03/12 02:36:04 joerg Exp $
36  */
37 
38 #include "opt_compat.h"
39 #include "opt_inet6.h"
40 #include "opt_inet.h"
41 
42 #include <sys/param.h>
43 #include <sys/malloc.h>
44 #include <sys/mbuf.h>
45 #include <sys/systm.h>
46 #include <sys/proc.h>
47 #include <sys/protosw.h>
48 #include <sys/socket.h>
49 #include <sys/socketvar.h>
50 #include <sys/socketops.h>
51 #include <sys/protosw.h>
52 #include <sys/kernel.h>
53 #include <sys/sockio.h>
54 #include <sys/syslog.h>
55 #include <sys/sysctl.h>
56 #include <sys/domain.h>
57 
58 #include <net/if.h>
59 #include <net/if_arp.h>
60 #include <net/if_dl.h>
61 #include <net/if_types.h>
62 #include <net/if_var.h>
63 #include <net/ifq_var.h>
64 #include <net/radix.h>
65 #include <net/route.h>
66 #include <machine/stdarg.h>
67 
68 #if defined(INET) || defined(INET6)
69 /*XXX*/
70 #include <netinet/in.h>
71 #include <netinet/in_var.h>
72 #include <netinet/if_ether.h>
73 #ifdef INET6
74 #include <machine/clock.h> /* XXX: temporal workaround for fxp issue */
75 #include <netinet6/in6_var.h>
76 #include <netinet6/in6_ifattach.h>
77 #endif
78 #endif
79 
80 #if defined(COMPAT_43)
81 #include <emulation/43bsd/43bsd_socket.h>
82 #endif /* COMPAT_43 */
83 
84 /*
85  * Support for non-ALTQ interfaces.
86  */
87 static int	ifq_classic_enqueue(struct ifaltq *, struct mbuf *,
88 				    struct altq_pktattr *);
89 static struct mbuf *
90 		ifq_classic_dequeue(struct ifaltq *, int);
91 static int	ifq_classic_request(struct ifaltq *, int, void *);
92 
93 /*
94  * System initialization
95  */
96 
97 static void	if_attachdomain(void *);
98 static void	if_attachdomain1(struct ifnet *);
99 static int ifconf (u_long, caddr_t, struct thread *);
100 static void ifinit (void *);
101 static void if_slowtimo (void *);
102 static void link_rtrequest (int, struct rtentry *, struct rt_addrinfo *);
103 static int  if_rtdel (struct radix_node *, void *);
104 
105 SYSINIT(interfaces, SI_SUB_PROTO_IF, SI_ORDER_FIRST, ifinit, NULL)
106 
107 MALLOC_DEFINE(M_IFADDR, "ifaddr", "interface address");
108 MALLOC_DEFINE(M_IFMADDR, "ether_multi", "link-level multicast address");
109 MALLOC_DEFINE(M_CLONE, "clone", "interface cloning framework");
110 
111 int	ifqmaxlen = IFQ_MAXLEN;
112 struct	ifnethead ifnet;	/* depend on static init XXX */
113 
114 #ifdef INET6
115 /*
116  * XXX: declare here to avoid to include many inet6 related files..
117  * should be more generalized?
118  */
119 extern void	nd6_setmtu (struct ifnet *);
120 #endif
121 
122 struct if_clone *if_clone_lookup (const char *, int *);
123 int if_clone_list (struct if_clonereq *);
124 
125 LIST_HEAD(, if_clone) if_cloners = LIST_HEAD_INITIALIZER(if_cloners);
126 int if_cloners_count;
127 
128 struct callout if_slowtimo_timer;
129 
130 /*
131  * Network interface utility routines.
132  *
133  * Routines with ifa_ifwith* names take sockaddr *'s as
134  * parameters.
135  */
136 /* ARGSUSED*/
137 void
138 ifinit(void *dummy)
139 {
140 	struct ifnet *ifp;
141 	int s;
142 
143 	callout_init(&if_slowtimo_timer);
144 
145 	s = splimp();
146 	TAILQ_FOREACH(ifp, &ifnet, if_link) {
147 		if (ifp->if_snd.ifq_maxlen == 0) {
148 			if_printf(ifp, "XXX: driver didn't set ifq_maxlen\n");
149 			ifp->if_snd.ifq_maxlen = ifqmaxlen;
150 		}
151 	}
152 	splx(s);
153 
154 	if_slowtimo(0);
155 }
156 
157 int if_index = 0;
158 struct ifaddr **ifnet_addrs;
159 struct ifnet **ifindex2ifnet = NULL;
160 
161 /*
162  * Attach an interface to the
163  * list of "active" interfaces.
164  */
165 void
166 if_attach(struct ifnet *ifp)
167 {
168 	unsigned socksize, ifasize;
169 	int namelen, masklen;
170 	struct sockaddr_dl *sdl;
171 	struct ifaddr *ifa;
172 	struct ifaltq *ifq;
173 
174 	static int if_indexlim = 8;
175 	static boolean_t inited;
176 
177 	if (!inited) {
178 		TAILQ_INIT(&ifnet);
179 		inited = TRUE;
180 	}
181 
182 	TAILQ_INSERT_TAIL(&ifnet, ifp, if_link);
183 	ifp->if_index = ++if_index;
184 	/*
185 	 * XXX -
186 	 * The old code would work if the interface passed a pre-existing
187 	 * chain of ifaddrs to this code.  We don't trust our callers to
188 	 * properly initialize the tailq, however, so we no longer allow
189 	 * this unlikely case.
190 	 */
191 	TAILQ_INIT(&ifp->if_addrhead);
192 	TAILQ_INIT(&ifp->if_prefixhead);
193 	LIST_INIT(&ifp->if_multiaddrs);
194 	getmicrotime(&ifp->if_lastchange);
195 	if (ifnet_addrs == NULL || if_index >= if_indexlim) {
196 		unsigned int n;
197 		caddr_t q;
198 
199 		if_indexlim <<= 1;
200 		n = if_indexlim * sizeof(struct ifaddr *);
201 		q = malloc(n, M_IFADDR, M_WAITOK | M_ZERO);
202 		if (ifnet_addrs != NULL) {
203 			bcopy(ifnet_addrs, q, n/2);
204 			free(ifnet_addrs, M_IFADDR);
205 		}
206 		ifnet_addrs = (struct ifaddr **)q;
207 
208 		/* grow ifindex2ifnet */
209 		n = if_indexlim * sizeof(struct ifnet *);
210 		q = malloc(n, M_IFADDR, M_WAITOK | M_ZERO);
211 		if (ifindex2ifnet) {
212 			bcopy(ifindex2ifnet, q, n/2);
213 			free(ifindex2ifnet, M_IFADDR);
214 		}
215 		ifindex2ifnet = (struct ifnet **)q;
216 	}
217 
218 	ifindex2ifnet[if_index] = ifp;
219 
220 	/*
221 	 * create a Link Level name for this device
222 	 */
223 	namelen = strlen(ifp->if_xname);
224 #define _offsetof(t, m) ((int)((caddr_t)&((t *)0)->m))
225 	masklen = _offsetof(struct sockaddr_dl, sdl_data[0]) + namelen;
226 	socksize = masklen + ifp->if_addrlen;
227 #define ROUNDUP(a) (1 + (((a) - 1) | (sizeof(long) - 1)))
228 	if (socksize < sizeof(*sdl))
229 		socksize = sizeof(*sdl);
230 	socksize = ROUNDUP(socksize);
231 	ifasize = sizeof(struct ifaddr) + 2 * socksize;
232 	ifa = malloc(ifasize, M_IFADDR, M_WAITOK | M_ZERO);
233 	sdl = (struct sockaddr_dl *)(ifa + 1);
234 	sdl->sdl_len = socksize;
235 	sdl->sdl_family = AF_LINK;
236 	bcopy(ifp->if_xname, sdl->sdl_data, namelen);
237 	sdl->sdl_nlen = namelen;
238 	sdl->sdl_index = ifp->if_index;
239 	sdl->sdl_type = ifp->if_type;
240 	ifnet_addrs[if_index - 1] = ifa;
241 	ifa->ifa_ifp = ifp;
242 	ifa->ifa_rtrequest = link_rtrequest;
243 	ifa->ifa_addr = (struct sockaddr *)sdl;
244 	sdl = (struct sockaddr_dl *)(socksize + (caddr_t)sdl);
245 	ifa->ifa_netmask = (struct sockaddr *)sdl;
246 	sdl->sdl_len = masklen;
247 	while (namelen != 0)
248 		sdl->sdl_data[--namelen] = 0xff;
249 	TAILQ_INSERT_HEAD(&ifp->if_addrhead, ifa, ifa_link);
250 
251 	EVENTHANDLER_INVOKE(ifnet_attach_event, ifp);
252 
253 	ifq = &ifp->if_snd;
254 	ifq->altq_type = 0;
255 	ifq->altq_disc = NULL;
256 	ifq->altq_flags &= ALTQF_CANTCHANGE;
257 	ifq->altq_tbr = NULL;
258 	ifq->altq_ifp = ifp;
259 	ifq->altq_enqueue = ifq_classic_enqueue;
260 	ifq->altq_dequeue = ifq_classic_dequeue;
261 	ifq->altq_request = ifq_classic_request;
262 
263 	if (!SLIST_EMPTY(&domains))
264 		if_attachdomain1(ifp);
265 
266 	/* Announce the interface. */
267 	rt_ifannouncemsg(ifp, IFAN_ARRIVAL);
268 }
269 
270 static void
271 if_attachdomain(void *dummy)
272 {
273 	struct ifnet *ifp;
274 	int s;
275 
276 	s = splnet();
277 	for (ifp = TAILQ_FIRST(&ifnet); ifp; ifp = TAILQ_NEXT(ifp, if_list))
278 		if_attachdomain1(ifp);
279 	splx(s);
280 }
281 SYSINIT(domainifattach, SI_SUB_PROTO_IFATTACHDOMAIN, SI_ORDER_FIRST,
282 	if_attachdomain, NULL);
283 
284 static void
285 if_attachdomain1(struct ifnet *ifp)
286 {
287 	struct domain *dp;
288 	int s;
289 
290 	s = splnet();
291 
292 	/* address family dependent data region */
293 	bzero(ifp->if_afdata, sizeof(ifp->if_afdata));
294 	SLIST_FOREACH(dp, &domains, dom_next)
295 		if (dp->dom_ifattach)
296 			ifp->if_afdata[dp->dom_family] =
297 				(*dp->dom_ifattach)(ifp);
298 	splx(s);
299 }
300 
301 /*
302  * Detach an interface, removing it from the
303  * list of "active" interfaces.
304  */
305 void
306 if_detach(struct ifnet *ifp)
307 {
308 	struct ifaddr *ifa;
309 	struct radix_node_head	*rnh;
310 	int s;
311 	int i;
312 	struct domain *dp;
313 
314 	EVENTHANDLER_INVOKE(ifnet_detach_event, ifp);
315 
316 	/*
317 	 * Remove routes and flush queues.
318 	 */
319 	s = splnet();
320 	if_down(ifp);
321 
322 	if (ifq_is_enabled(&ifp->if_snd))
323 		altq_disable(&ifp->if_snd);
324 	if (ifq_is_attached(&ifp->if_snd))
325 		altq_detach(&ifp->if_snd);
326 
327 	/*
328 	 * Remove address from ifnet_addrs[] and maybe decrement if_index.
329 	 * Clean up all addresses.
330 	 */
331 	ifnet_addrs[ifp->if_index - 1] = 0;
332 	while (if_index > 0 && ifnet_addrs[if_index - 1] == 0)
333 		if_index--;
334 
335 	for (ifa = TAILQ_FIRST(&ifp->if_addrhead); ifa;
336 	     ifa = TAILQ_FIRST(&ifp->if_addrhead)) {
337 #ifdef INET
338 		/* XXX: Ugly!! ad hoc just for INET */
339 		if (ifa->ifa_addr && ifa->ifa_addr->sa_family == AF_INET) {
340 			struct ifaliasreq ifr;
341 
342 			bzero(&ifr, sizeof ifr);
343 			ifr.ifra_addr = *ifa->ifa_addr;
344 			if (ifa->ifa_dstaddr)
345 				ifr.ifra_broadaddr = *ifa->ifa_dstaddr;
346 			if (in_control(NULL, SIOCDIFADDR, (caddr_t)&ifr, ifp,
347 				       NULL) == 0)
348 				continue;
349 		}
350 #endif /* INET */
351 #ifdef INET6
352 		if (ifa->ifa_addr && ifa->ifa_addr->sa_family == AF_INET6) {
353 			in6_purgeaddr(ifa);
354 			/* ifp_addrhead is already updated */
355 			continue;
356 		}
357 #endif /* INET6 */
358 		TAILQ_REMOVE(&ifp->if_addrhead, ifa, ifa_link);
359 		IFAFREE(ifa);
360 	}
361 
362 #ifdef INET6
363 	/*
364 	 * Remove all IPv6 kernel structs related to ifp.  This should be done
365 	 * before removing routing entries below, since IPv6 interface direct
366 	 * routes are expected to be removed by the IPv6-specific kernel API.
367 	 * Otherwise, the kernel will detect some inconsistency and bark it.
368 	 */
369 	in6_ifdetach(ifp);
370 #endif
371 
372 	/*
373 	 * Delete all remaining routes using this interface
374 	 * Unfortuneatly the only way to do this is to slog through
375 	 * the entire routing table looking for routes which point
376 	 * to this interface...oh well...
377 	 */
378 	for (i = 1; i <= AF_MAX; i++) {
379 		if ((rnh = rt_tables[i]) == NULL)
380 			continue;
381 		rnh->rnh_walktree(rnh, if_rtdel, ifp);
382 	}
383 
384 	/* Announce that the interface is gone. */
385 	rt_ifannouncemsg(ifp, IFAN_DEPARTURE);
386 
387 	SLIST_FOREACH(dp, &domains, dom_next)
388 		if (dp->dom_ifdetach && ifp->if_afdata[dp->dom_family])
389 			(*dp->dom_ifdetach)(ifp,
390 				ifp->if_afdata[dp->dom_family]);
391 
392 	ifindex2ifnet[ifp->if_index] = NULL;
393 
394 	TAILQ_REMOVE(&ifnet, ifp, if_link);
395 	splx(s);
396 }
397 
398 /*
399  * Delete Routes for a Network Interface
400  *
401  * Called for each routing entry via the rnh->rnh_walktree() call above
402  * to delete all route entries referencing a detaching network interface.
403  *
404  * Arguments:
405  *	rn	pointer to node in the routing table
406  *	arg	argument passed to rnh->rnh_walktree() - detaching interface
407  *
408  * Returns:
409  *	0	successful
410  *	errno	failed - reason indicated
411  *
412  */
413 static int
414 if_rtdel(struct radix_node *rn, void *arg)
415 {
416 	struct rtentry	*rt = (struct rtentry *)rn;
417 	struct ifnet	*ifp = arg;
418 	int		err;
419 
420 	if (rt->rt_ifp == ifp) {
421 
422 		/*
423 		 * Protect (sorta) against walktree recursion problems
424 		 * with cloned routes
425 		 */
426 		if (!(rt->rt_flags & RTF_UP))
427 			return (0);
428 
429 		err = rtrequest(RTM_DELETE, rt_key(rt), rt->rt_gateway,
430 				rt_mask(rt), rt->rt_flags,
431 				(struct rtentry **) NULL);
432 		if (err) {
433 			log(LOG_WARNING, "if_rtdel: error %d\n", err);
434 		}
435 	}
436 
437 	return (0);
438 }
439 
440 /*
441  * Create a clone network interface.
442  */
443 int
444 if_clone_create(char *name, int len)
445 {
446 	struct if_clone *ifc;
447 	char *dp;
448 	int wildcard, bytoff, bitoff;
449 	int unit;
450 	int err;
451 
452 	ifc = if_clone_lookup(name, &unit);
453 	if (ifc == NULL)
454 		return (EINVAL);
455 
456 	if (ifunit(name) != NULL)
457 		return (EEXIST);
458 
459 	bytoff = bitoff = 0;
460 	wildcard = (unit < 0);
461 	/*
462 	 * Find a free unit if none was given.
463 	 */
464 	if (wildcard) {
465 		while (bytoff < ifc->ifc_bmlen &&
466 		    ifc->ifc_units[bytoff] == 0xff)
467 			bytoff++;
468 		if (bytoff >= ifc->ifc_bmlen)
469 			return (ENOSPC);
470 		while ((ifc->ifc_units[bytoff] & (1 << bitoff)) != 0)
471 			bitoff++;
472 		unit = (bytoff << 3) + bitoff;
473 	}
474 
475 	if (unit > ifc->ifc_maxunit)
476 		return (ENXIO);
477 
478 	err = (*ifc->ifc_create)(ifc, unit);
479 	if (err != 0)
480 		return (err);
481 
482 	if (!wildcard) {
483 		bytoff = unit >> 3;
484 		bitoff = unit - (bytoff << 3);
485 	}
486 
487 	/*
488 	 * Allocate the unit in the bitmap.
489 	 */
490 	KASSERT((ifc->ifc_units[bytoff] & (1 << bitoff)) == 0,
491 	    ("%s: bit is already set", __func__));
492 	ifc->ifc_units[bytoff] |= (1 << bitoff);
493 
494 	/* In the wildcard case, we need to update the name. */
495 	if (wildcard) {
496 		for (dp = name; *dp != '\0'; dp++);
497 		if (snprintf(dp, len - (dp-name), "%d", unit) >
498 		    len - (dp-name) - 1) {
499 			/*
500 			 * This can only be a programmer error and
501 			 * there's no straightforward way to recover if
502 			 * it happens.
503 			 */
504 			panic("if_clone_create(): interface name too long");
505 		}
506 
507 	}
508 
509 	EVENTHANDLER_INVOKE(if_clone_event, ifc);
510 
511 	return (0);
512 }
513 
514 /*
515  * Destroy a clone network interface.
516  */
517 int
518 if_clone_destroy(const char *name)
519 {
520 	struct if_clone *ifc;
521 	struct ifnet *ifp;
522 	int bytoff, bitoff;
523 	int unit;
524 
525 	ifc = if_clone_lookup(name, &unit);
526 	if (ifc == NULL)
527 		return (EINVAL);
528 
529 	if (unit < ifc->ifc_minifs)
530 		return (EINVAL);
531 
532 	ifp = ifunit(name);
533 	if (ifp == NULL)
534 		return (ENXIO);
535 
536 	if (ifc->ifc_destroy == NULL)
537 		return (EOPNOTSUPP);
538 
539 	(*ifc->ifc_destroy)(ifp);
540 
541 	/*
542 	 * Compute offset in the bitmap and deallocate the unit.
543 	 */
544 	bytoff = unit >> 3;
545 	bitoff = unit - (bytoff << 3);
546 	KASSERT((ifc->ifc_units[bytoff] & (1 << bitoff)) != 0,
547 	    ("%s: bit is already cleared", __func__));
548 	ifc->ifc_units[bytoff] &= ~(1 << bitoff);
549 	return (0);
550 }
551 
552 /*
553  * Look up a network interface cloner.
554  */
555 struct if_clone *
556 if_clone_lookup(const char *name, int *unitp)
557 {
558 	struct if_clone *ifc;
559 	const char *cp;
560 	int i;
561 
562 	for (ifc = LIST_FIRST(&if_cloners); ifc != NULL;) {
563 		for (cp = name, i = 0; i < ifc->ifc_namelen; i++, cp++) {
564 			if (ifc->ifc_name[i] != *cp)
565 				goto next_ifc;
566 		}
567 		goto found_name;
568  next_ifc:
569 		ifc = LIST_NEXT(ifc, ifc_list);
570 	}
571 
572 	/* No match. */
573 	return ((struct if_clone *)NULL);
574 
575  found_name:
576 	if (*cp == '\0') {
577 		i = -1;
578 	} else {
579 		for (i = 0; *cp != '\0'; cp++) {
580 			if (*cp < '0' || *cp > '9') {
581 				/* Bogus unit number. */
582 				return (NULL);
583 			}
584 			i = (i * 10) + (*cp - '0');
585 		}
586 	}
587 
588 	if (unitp != NULL)
589 		*unitp = i;
590 	return (ifc);
591 }
592 
593 /*
594  * Register a network interface cloner.
595  */
596 void
597 if_clone_attach(struct if_clone *ifc)
598 {
599 	int bytoff, bitoff;
600 	int err;
601 	int len, maxclone;
602 	int unit;
603 
604 	KASSERT(ifc->ifc_minifs - 1 <= ifc->ifc_maxunit,
605 	    ("%s: %s requested more units then allowed (%d > %d)",
606 	    __func__, ifc->ifc_name, ifc->ifc_minifs,
607 	    ifc->ifc_maxunit + 1));
608 	/*
609 	 * Compute bitmap size and allocate it.
610 	 */
611 	maxclone = ifc->ifc_maxunit + 1;
612 	len = maxclone >> 3;
613 	if ((len << 3) < maxclone)
614 		len++;
615 	ifc->ifc_units = malloc(len, M_CLONE, M_WAITOK | M_ZERO);
616 	ifc->ifc_bmlen = len;
617 
618 	LIST_INSERT_HEAD(&if_cloners, ifc, ifc_list);
619 	if_cloners_count++;
620 
621 	for (unit = 0; unit < ifc->ifc_minifs; unit++) {
622 		err = (*ifc->ifc_create)(ifc, unit);
623 		KASSERT(err == 0,
624 		    ("%s: failed to create required interface %s%d",
625 		    __func__, ifc->ifc_name, unit));
626 
627 		/* Allocate the unit in the bitmap. */
628 		bytoff = unit >> 3;
629 		bitoff = unit - (bytoff << 3);
630 		ifc->ifc_units[bytoff] |= (1 << bitoff);
631 	}
632 }
633 
634 /*
635  * Unregister a network interface cloner.
636  */
637 void
638 if_clone_detach(struct if_clone *ifc)
639 {
640 
641 	LIST_REMOVE(ifc, ifc_list);
642 	free(ifc->ifc_units, M_CLONE);
643 	if_cloners_count--;
644 }
645 
646 /*
647  * Provide list of interface cloners to userspace.
648  */
649 int
650 if_clone_list(struct if_clonereq *ifcr)
651 {
652 	char outbuf[IFNAMSIZ], *dst;
653 	struct if_clone *ifc;
654 	int count, error = 0;
655 
656 	ifcr->ifcr_total = if_cloners_count;
657 	if ((dst = ifcr->ifcr_buffer) == NULL) {
658 		/* Just asking how many there are. */
659 		return (0);
660 	}
661 
662 	if (ifcr->ifcr_count < 0)
663 		return (EINVAL);
664 
665 	count = (if_cloners_count < ifcr->ifcr_count) ?
666 	    if_cloners_count : ifcr->ifcr_count;
667 
668 	for (ifc = LIST_FIRST(&if_cloners); ifc != NULL && count != 0;
669 	     ifc = LIST_NEXT(ifc, ifc_list), count--, dst += IFNAMSIZ) {
670 		strlcpy(outbuf, ifc->ifc_name, IFNAMSIZ);
671 		error = copyout(outbuf, dst, IFNAMSIZ);
672 		if (error)
673 			break;
674 	}
675 
676 	return (error);
677 }
678 
679 /*
680  * Locate an interface based on a complete address.
681  */
682 struct ifaddr *
683 ifa_ifwithaddr(struct sockaddr *addr)
684 {
685 	struct ifnet *ifp;
686 	struct ifaddr *ifa;
687 
688 	TAILQ_FOREACH(ifp, &ifnet, if_link)
689 	    TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
690 		if (ifa->ifa_addr->sa_family != addr->sa_family)
691 			continue;
692 		if (sa_equal(addr, ifa->ifa_addr))
693 			return (ifa);
694 		if ((ifp->if_flags & IFF_BROADCAST) && ifa->ifa_broadaddr &&
695 		    /* IPv6 doesn't have broadcast */
696 		    ifa->ifa_broadaddr->sa_len != 0 &&
697 		    sa_equal(ifa->ifa_broadaddr, addr))
698 			return (ifa);
699 	}
700 	return ((struct ifaddr *)NULL);
701 }
702 /*
703  * Locate the point to point interface with a given destination address.
704  */
705 struct ifaddr *
706 ifa_ifwithdstaddr(struct sockaddr *addr)
707 {
708 	struct ifnet *ifp;
709 	struct ifaddr *ifa;
710 
711 	TAILQ_FOREACH(ifp, &ifnet, if_link)
712 	    if (ifp->if_flags & IFF_POINTOPOINT)
713 		TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
714 			if (ifa->ifa_addr->sa_family != addr->sa_family)
715 				continue;
716 			if (ifa->ifa_dstaddr &&
717 			    sa_equal(addr, ifa->ifa_dstaddr))
718 				return (ifa);
719 	}
720 	return ((struct ifaddr *)NULL);
721 }
722 
723 /*
724  * Find an interface on a specific network.  If many, choice
725  * is most specific found.
726  */
727 struct ifaddr *
728 ifa_ifwithnet(struct sockaddr *addr)
729 {
730 	struct ifnet *ifp;
731 	struct ifaddr *ifa;
732 	struct ifaddr *ifa_maybe = (struct ifaddr *) 0;
733 	u_int af = addr->sa_family;
734 	char *addr_data = addr->sa_data, *cplim;
735 
736 	/*
737 	 * AF_LINK addresses can be looked up directly by their index number,
738 	 * so do that if we can.
739 	 */
740 	if (af == AF_LINK) {
741 	    struct sockaddr_dl *sdl = (struct sockaddr_dl *)addr;
742 
743 	    if (sdl->sdl_index && sdl->sdl_index <= if_index)
744 		return (ifnet_addrs[sdl->sdl_index - 1]);
745 	}
746 
747 	/*
748 	 * Scan though each interface, looking for ones that have
749 	 * addresses in this address family.
750 	 */
751 	TAILQ_FOREACH(ifp, &ifnet, if_link) {
752 		TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
753 			char *cp, *cp2, *cp3;
754 
755 			if (ifa->ifa_addr->sa_family != af)
756 next:				continue;
757 			if (af == AF_INET && ifp->if_flags & IFF_POINTOPOINT) {
758 				/*
759 				 * This is a bit broken as it doesn't
760 				 * take into account that the remote end may
761 				 * be a single node in the network we are
762 				 * looking for.
763 				 * The trouble is that we don't know the
764 				 * netmask for the remote end.
765 				 */
766 				if (ifa->ifa_dstaddr != NULL &&
767 				    sa_equal(addr, ifa->ifa_dstaddr))
768 					return (ifa);
769 			} else {
770 				/*
771 				 * if we have a special address handler,
772 				 * then use it instead of the generic one.
773 				 */
774 				if (ifa->ifa_claim_addr) {
775 					if ((*ifa->ifa_claim_addr)(ifa, addr)) {
776 						return (ifa);
777 					} else {
778 						continue;
779 					}
780 				}
781 
782 				/*
783 				 * Scan all the bits in the ifa's address.
784 				 * If a bit dissagrees with what we are
785 				 * looking for, mask it with the netmask
786 				 * to see if it really matters.
787 				 * (A byte at a time)
788 				 */
789 				if (ifa->ifa_netmask == 0)
790 					continue;
791 				cp = addr_data;
792 				cp2 = ifa->ifa_addr->sa_data;
793 				cp3 = ifa->ifa_netmask->sa_data;
794 				cplim = ifa->ifa_netmask->sa_len +
795 					(char *)ifa->ifa_netmask;
796 				while (cp3 < cplim)
797 					if ((*cp++ ^ *cp2++) & *cp3++)
798 						goto next; /* next address! */
799 				/*
800 				 * If the netmask of what we just found
801 				 * is more specific than what we had before
802 				 * (if we had one) then remember the new one
803 				 * before continuing to search
804 				 * for an even better one.
805 				 */
806 				if (ifa_maybe == 0 ||
807 				    rn_refines((char *)ifa->ifa_netmask,
808 					       (char *)ifa_maybe->ifa_netmask))
809 					ifa_maybe = ifa;
810 			}
811 		}
812 	}
813 	return (ifa_maybe);
814 }
815 
816 /*
817  * Find an interface address specific to an interface best matching
818  * a given address.
819  */
820 struct ifaddr *
821 ifaof_ifpforaddr(struct sockaddr *addr, struct ifnet *ifp)
822 {
823 	struct ifaddr *ifa;
824 	char *cp, *cp2, *cp3;
825 	char *cplim;
826 	struct ifaddr *ifa_maybe = 0;
827 	u_int af = addr->sa_family;
828 
829 	if (af >= AF_MAX)
830 		return (0);
831 	TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
832 		if (ifa->ifa_addr->sa_family != af)
833 			continue;
834 		if (ifa_maybe == 0)
835 			ifa_maybe = ifa;
836 		if (ifa->ifa_netmask == NULL) {
837 			if (sa_equal(addr, ifa->ifa_addr) ||
838 			    (ifa->ifa_dstaddr != NULL &&
839 			     sa_equal(addr, ifa->ifa_dstaddr)))
840 				return (ifa);
841 			continue;
842 		}
843 		if (ifp->if_flags & IFF_POINTOPOINT) {
844 			if (sa_equal(addr, ifa->ifa_dstaddr))
845 				return (ifa);
846 		} else {
847 			cp = addr->sa_data;
848 			cp2 = ifa->ifa_addr->sa_data;
849 			cp3 = ifa->ifa_netmask->sa_data;
850 			cplim = ifa->ifa_netmask->sa_len + (char *)ifa->ifa_netmask;
851 			for (; cp3 < cplim; cp3++)
852 				if ((*cp++ ^ *cp2++) & *cp3)
853 					break;
854 			if (cp3 == cplim)
855 				return (ifa);
856 		}
857 	}
858 	return (ifa_maybe);
859 }
860 
861 #include <net/route.h>
862 
863 /*
864  * Default action when installing a route with a Link Level gateway.
865  * Lookup an appropriate real ifa to point to.
866  * This should be moved to /sys/net/link.c eventually.
867  */
868 static void
869 link_rtrequest(int cmd, struct rtentry *rt, struct rt_addrinfo *info)
870 {
871 	struct ifaddr *ifa;
872 	struct sockaddr *dst;
873 	struct ifnet *ifp;
874 
875 	if (cmd != RTM_ADD || (ifa = rt->rt_ifa) == NULL ||
876 	    (ifp = ifa->ifa_ifp) == NULL || (dst = rt_key(rt)) == NULL)
877 		return;
878 	ifa = ifaof_ifpforaddr(dst, ifp);
879 	if (ifa != NULL) {
880 		IFAFREE(rt->rt_ifa);
881 		IFAREF(ifa);
882 		rt->rt_ifa = ifa;
883 		if (ifa->ifa_rtrequest && ifa->ifa_rtrequest != link_rtrequest)
884 			ifa->ifa_rtrequest(cmd, rt, info);
885 	}
886 }
887 
888 /*
889  * Mark an interface down and notify protocols of
890  * the transition.
891  * NOTE: must be called at splnet or eqivalent.
892  */
893 void
894 if_unroute(struct ifnet *ifp, int flag, int fam)
895 {
896 	struct ifaddr *ifa;
897 
898 	ifp->if_flags &= ~flag;
899 	getmicrotime(&ifp->if_lastchange);
900 	TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link)
901 		if (fam == PF_UNSPEC || (fam == ifa->ifa_addr->sa_family))
902 			pfctlinput(PRC_IFDOWN, ifa->ifa_addr);
903 	ifq_purge(&ifp->if_snd);
904 	rt_ifmsg(ifp);
905 }
906 
907 /*
908  * Mark an interface up and notify protocols of
909  * the transition.
910  * NOTE: must be called at splnet or eqivalent.
911  */
912 void
913 if_route(struct ifnet *ifp, int flag, int fam)
914 {
915 	struct ifaddr *ifa;
916 
917 	ifp->if_flags |= flag;
918 	getmicrotime(&ifp->if_lastchange);
919 	TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link)
920 		if (fam == PF_UNSPEC || (fam == ifa->ifa_addr->sa_family))
921 			pfctlinput(PRC_IFUP, ifa->ifa_addr);
922 	rt_ifmsg(ifp);
923 #ifdef INET6
924 	in6_if_up(ifp);
925 #endif
926 }
927 
928 /*
929  * Mark an interface down and notify protocols of the transition.  An
930  * interface going down is also considered to be a synchronizing event.
931  * We must ensure that all packet processing related to the interface
932  * has completed before we return so e.g. the caller can free the ifnet
933  * structure that the mbufs may be referencing.
934  *
935  * NOTE: must be called at splnet or eqivalent.
936  */
937 void
938 if_down(struct ifnet *ifp)
939 {
940 
941 	if_unroute(ifp, IFF_UP, AF_UNSPEC);
942 	netmsg_service_sync();
943 }
944 
945 /*
946  * Mark an interface up and notify protocols of
947  * the transition.
948  * NOTE: must be called at splnet or eqivalent.
949  */
950 void
951 if_up(struct ifnet *ifp)
952 {
953 
954 	if_route(ifp, IFF_UP, AF_UNSPEC);
955 }
956 
957 /*
958  * Handle interface watchdog timer routines.  Called
959  * from softclock, we decrement timers (if set) and
960  * call the appropriate interface routine on expiration.
961  */
962 static void
963 if_slowtimo(void *arg)
964 {
965 	struct ifnet *ifp;
966 	int s = splimp();
967 
968 	TAILQ_FOREACH(ifp, &ifnet, if_link) {
969 		if (ifp->if_timer == 0 || --ifp->if_timer)
970 			continue;
971 		if (ifp->if_watchdog)
972 			(*ifp->if_watchdog)(ifp);
973 	}
974 	splx(s);
975 	callout_reset(&if_slowtimo_timer, hz / IFNET_SLOWHZ, if_slowtimo, NULL);
976 }
977 
978 /*
979  * Map interface name to
980  * interface structure pointer.
981  */
982 struct ifnet *
983 ifunit(const char *name)
984 {
985 	struct ifnet *ifp;
986 
987 	/*
988 	 * Search all the interfaces for this name/number
989 	 */
990 
991 	TAILQ_FOREACH(ifp, &ifnet, if_link) {
992 		if (strncmp(ifp->if_xname, name, IFNAMSIZ) == 0)
993 			break;
994 	}
995 	return (ifp);
996 }
997 
998 
999 /*
1000  * Map interface name in a sockaddr_dl to
1001  * interface structure pointer.
1002  */
1003 struct ifnet *
1004 if_withname(struct sockaddr *sa)
1005 {
1006 	char ifname[IFNAMSIZ+1];
1007 	struct sockaddr_dl *sdl = (struct sockaddr_dl *)sa;
1008 
1009 	if ( (sa->sa_family != AF_LINK) || (sdl->sdl_nlen == 0) ||
1010 	     (sdl->sdl_nlen > IFNAMSIZ) )
1011 		return NULL;
1012 
1013 	/*
1014 	 * ifunit wants a null-terminated name.  It may not be null-terminated
1015 	 * in the sockaddr.  We don't want to change the caller's sockaddr,
1016 	 * and there might not be room to put the trailing null anyway, so we
1017 	 * make a local copy that we know we can null terminate safely.
1018 	 */
1019 
1020 	bcopy(sdl->sdl_data, ifname, sdl->sdl_nlen);
1021 	ifname[sdl->sdl_nlen] = '\0';
1022 	return ifunit(ifname);
1023 }
1024 
1025 
1026 /*
1027  * Interface ioctls.
1028  */
1029 int
1030 ifioctl(struct socket *so, u_long cmd, caddr_t data, struct thread *td)
1031 {
1032 	struct ifnet *ifp;
1033 	struct ifreq *ifr;
1034 	struct ifstat *ifs;
1035 	int error;
1036 	short oif_flags;
1037 	int new_flags;
1038 	size_t namelen, onamelen;
1039 	char new_name[IFNAMSIZ];
1040 	struct ifaddr *ifa;
1041 	struct sockaddr_dl *sdl;
1042 
1043 	switch (cmd) {
1044 
1045 	case SIOCGIFCONF:
1046 	case OSIOCGIFCONF:
1047 		return (ifconf(cmd, data, td));
1048 	}
1049 	ifr = (struct ifreq *)data;
1050 
1051 	switch (cmd) {
1052 	case SIOCIFCREATE:
1053 	case SIOCIFDESTROY:
1054 		if ((error = suser(td)) != 0)
1055 			return (error);
1056 		return ((cmd == SIOCIFCREATE) ?
1057 			if_clone_create(ifr->ifr_name, sizeof(ifr->ifr_name)) :
1058 			if_clone_destroy(ifr->ifr_name));
1059 
1060 	case SIOCIFGCLONERS:
1061 		return (if_clone_list((struct if_clonereq *)data));
1062 	}
1063 
1064 	ifp = ifunit(ifr->ifr_name);
1065 	if (ifp == 0)
1066 		return (ENXIO);
1067 	switch (cmd) {
1068 
1069 	case SIOCGIFFLAGS:
1070 		ifr->ifr_flags = ifp->if_flags;
1071 		ifr->ifr_flagshigh = ifp->if_flags >> 16;
1072 		break;
1073 
1074 	case SIOCGIFCAP:
1075 		ifr->ifr_reqcap = ifp->if_capabilities;
1076 		ifr->ifr_curcap = ifp->if_capenable;
1077 		break;
1078 
1079 	case SIOCGIFMETRIC:
1080 		ifr->ifr_metric = ifp->if_metric;
1081 		break;
1082 
1083 	case SIOCGIFMTU:
1084 		ifr->ifr_mtu = ifp->if_mtu;
1085 		break;
1086 
1087 	case SIOCGIFPHYS:
1088 		ifr->ifr_phys = ifp->if_physical;
1089 		break;
1090 
1091 	case SIOCSIFFLAGS:
1092 		error = suser(td);
1093 		if (error)
1094 			return (error);
1095 		new_flags = (ifr->ifr_flags & 0xffff) |
1096 		    (ifr->ifr_flagshigh << 16);
1097 		if (ifp->if_flags & IFF_SMART) {
1098 			/* Smart drivers twiddle their own routes */
1099 		} else if (ifp->if_flags & IFF_UP &&
1100 		    (new_flags & IFF_UP) == 0) {
1101 			int s = splimp();
1102 			if_down(ifp);
1103 			splx(s);
1104 		} else if (new_flags & IFF_UP &&
1105 		    (ifp->if_flags & IFF_UP) == 0) {
1106 			int s = splimp();
1107 			if_up(ifp);
1108 			splx(s);
1109 		}
1110 		ifp->if_flags = (ifp->if_flags & IFF_CANTCHANGE) |
1111 			(new_flags &~ IFF_CANTCHANGE);
1112 		if (new_flags & IFF_PPROMISC) {
1113 			/* Permanently promiscuous mode requested */
1114 			ifp->if_flags |= IFF_PROMISC;
1115 		} else if (ifp->if_pcount == 0) {
1116 			ifp->if_flags &= ~IFF_PROMISC;
1117 		}
1118 		if (ifp->if_ioctl)
1119 			(*ifp->if_ioctl)(ifp, cmd, data, td->td_proc->p_ucred);
1120 		getmicrotime(&ifp->if_lastchange);
1121 		break;
1122 
1123 	case SIOCSIFCAP:
1124 		error = suser(td);
1125 		if (error)
1126 			return (error);
1127 		if (ifr->ifr_reqcap & ~ifp->if_capabilities)
1128 			return (EINVAL);
1129 		(*ifp->if_ioctl)(ifp, cmd, data, td->td_proc->p_ucred);
1130 		break;
1131 
1132 	case SIOCSIFNAME:
1133 		error = suser(td);
1134 		if (error != 0)
1135 			return (error);
1136 		error = copyinstr(ifr->ifr_data, new_name, IFNAMSIZ, NULL);
1137 		if (error != 0)
1138 			return (error);
1139 		if (new_name[0] == '\0')
1140 			return (EINVAL);
1141 		if (ifunit(new_name) != NULL)
1142 			return (EEXIST);
1143 
1144 		EVENTHANDLER_INVOKE(ifnet_detach_event, ifp);
1145 
1146 		/* Announce the departure of the interface. */
1147 		rt_ifannouncemsg(ifp, IFAN_DEPARTURE);
1148 
1149 		strlcpy(ifp->if_xname, new_name, sizeof(ifp->if_xname));
1150 		ifa = TAILQ_FIRST(&ifp->if_addrhead);
1151 		/* XXX IFA_LOCK(ifa); */
1152 		sdl = (struct sockaddr_dl *)ifa->ifa_addr;
1153 		namelen = strlen(new_name);
1154 		onamelen = sdl->sdl_nlen;
1155 		/*
1156 		 * Move the address if needed.  This is safe because we
1157 		 * allocate space for a name of length IFNAMSIZ when we
1158 		 * create this in if_attach().
1159 		 */
1160 		if (namelen != onamelen) {
1161 			bcopy(sdl->sdl_data + onamelen,
1162 			    sdl->sdl_data + namelen, sdl->sdl_alen);
1163 		}
1164 		bcopy(new_name, sdl->sdl_data, namelen);
1165 		sdl->sdl_nlen = namelen;
1166 		sdl = (struct sockaddr_dl *)ifa->ifa_netmask;
1167 		bzero(sdl->sdl_data, onamelen);
1168 		while (namelen != 0)
1169 			sdl->sdl_data[--namelen] = 0xff;
1170 		/* XXX IFA_UNLOCK(ifa) */
1171 
1172 		EVENTHANDLER_INVOKE(ifnet_attach_event, ifp);
1173 
1174 		/* Announce the return of the interface. */
1175 		rt_ifannouncemsg(ifp, IFAN_ARRIVAL);
1176 		break;
1177 
1178 	case SIOCSIFMETRIC:
1179 		error = suser(td);
1180 		if (error)
1181 			return (error);
1182 		ifp->if_metric = ifr->ifr_metric;
1183 		getmicrotime(&ifp->if_lastchange);
1184 		break;
1185 
1186 	case SIOCSIFPHYS:
1187 		error = suser(td);
1188 		if (error)
1189 			return error;
1190 		if (!ifp->if_ioctl)
1191 		        return EOPNOTSUPP;
1192 		error = (*ifp->if_ioctl)(ifp, cmd, data, td->td_proc->p_ucred);
1193 		if (error == 0)
1194 			getmicrotime(&ifp->if_lastchange);
1195 		return (error);
1196 
1197 	case SIOCSIFMTU:
1198 	{
1199 		u_long oldmtu = ifp->if_mtu;
1200 
1201 		error = suser(td);
1202 		if (error)
1203 			return (error);
1204 		if (ifp->if_ioctl == NULL)
1205 			return (EOPNOTSUPP);
1206 		if (ifr->ifr_mtu < IF_MINMTU || ifr->ifr_mtu > IF_MAXMTU)
1207 			return (EINVAL);
1208 		error = (*ifp->if_ioctl)(ifp, cmd, data, td->td_proc->p_ucred);
1209 		if (error == 0) {
1210 			getmicrotime(&ifp->if_lastchange);
1211 			rt_ifmsg(ifp);
1212 		}
1213 		/*
1214 		 * If the link MTU changed, do network layer specific procedure.
1215 		 */
1216 		if (ifp->if_mtu != oldmtu) {
1217 #ifdef INET6
1218 			nd6_setmtu(ifp);
1219 #endif
1220 		}
1221 		return (error);
1222 	}
1223 
1224 	case SIOCADDMULTI:
1225 	case SIOCDELMULTI:
1226 		error = suser(td);
1227 		if (error)
1228 			return (error);
1229 
1230 		/* Don't allow group membership on non-multicast interfaces. */
1231 		if ((ifp->if_flags & IFF_MULTICAST) == 0)
1232 			return EOPNOTSUPP;
1233 
1234 		/* Don't let users screw up protocols' entries. */
1235 		if (ifr->ifr_addr.sa_family != AF_LINK)
1236 			return EINVAL;
1237 
1238 		if (cmd == SIOCADDMULTI) {
1239 			struct ifmultiaddr *ifma;
1240 			error = if_addmulti(ifp, &ifr->ifr_addr, &ifma);
1241 		} else {
1242 			error = if_delmulti(ifp, &ifr->ifr_addr);
1243 		}
1244 		if (error == 0)
1245 			getmicrotime(&ifp->if_lastchange);
1246 		return error;
1247 
1248 	case SIOCSIFPHYADDR:
1249 	case SIOCDIFPHYADDR:
1250 #ifdef INET6
1251 	case SIOCSIFPHYADDR_IN6:
1252 #endif
1253 	case SIOCSLIFPHYADDR:
1254         case SIOCSIFMEDIA:
1255 	case SIOCSIFGENERIC:
1256 		error = suser(td);
1257 		if (error)
1258 			return (error);
1259 		if (ifp->if_ioctl == 0)
1260 			return (EOPNOTSUPP);
1261 		error = (*ifp->if_ioctl)(ifp, cmd, data, td->td_proc->p_ucred);
1262 		if (error == 0)
1263 			getmicrotime(&ifp->if_lastchange);
1264 		return error;
1265 
1266 	case SIOCGIFSTATUS:
1267 		ifs = (struct ifstat *)data;
1268 		ifs->ascii[0] = '\0';
1269 
1270 	case SIOCGIFPSRCADDR:
1271 	case SIOCGIFPDSTADDR:
1272 	case SIOCGLIFPHYADDR:
1273 	case SIOCGIFMEDIA:
1274 	case SIOCGIFGENERIC:
1275 		if (ifp->if_ioctl == 0)
1276 			return (EOPNOTSUPP);
1277 		return ((*ifp->if_ioctl)(ifp, cmd, data, td->td_proc->p_ucred));
1278 
1279 	case SIOCSIFLLADDR:
1280 		error = suser(td);
1281 		if (error)
1282 			return (error);
1283 		return if_setlladdr(ifp,
1284 		    ifr->ifr_addr.sa_data, ifr->ifr_addr.sa_len);
1285 
1286 	default:
1287 		oif_flags = ifp->if_flags;
1288 		if (so->so_proto == 0)
1289 			return (EOPNOTSUPP);
1290 #ifndef COMPAT_43
1291 		error = so_pru_control(so, cmd, data, ifp, td);
1292 #else
1293 	    {
1294 		int ocmd = cmd;
1295 
1296 		switch (cmd) {
1297 
1298 		case SIOCSIFDSTADDR:
1299 		case SIOCSIFADDR:
1300 		case SIOCSIFBRDADDR:
1301 		case SIOCSIFNETMASK:
1302 #if BYTE_ORDER != BIG_ENDIAN
1303 			if (ifr->ifr_addr.sa_family == 0 &&
1304 			    ifr->ifr_addr.sa_len < 16) {
1305 				ifr->ifr_addr.sa_family = ifr->ifr_addr.sa_len;
1306 				ifr->ifr_addr.sa_len = 16;
1307 			}
1308 #else
1309 			if (ifr->ifr_addr.sa_len == 0)
1310 				ifr->ifr_addr.sa_len = 16;
1311 #endif
1312 			break;
1313 
1314 		case OSIOCGIFADDR:
1315 			cmd = SIOCGIFADDR;
1316 			break;
1317 
1318 		case OSIOCGIFDSTADDR:
1319 			cmd = SIOCGIFDSTADDR;
1320 			break;
1321 
1322 		case OSIOCGIFBRDADDR:
1323 			cmd = SIOCGIFBRDADDR;
1324 			break;
1325 
1326 		case OSIOCGIFNETMASK:
1327 			cmd = SIOCGIFNETMASK;
1328 		}
1329 		error =  so_pru_control(so, cmd, data, ifp, td);
1330 		switch (ocmd) {
1331 
1332 		case OSIOCGIFADDR:
1333 		case OSIOCGIFDSTADDR:
1334 		case OSIOCGIFBRDADDR:
1335 		case OSIOCGIFNETMASK:
1336 			*(u_short *)&ifr->ifr_addr = ifr->ifr_addr.sa_family;
1337 
1338 		}
1339 	    }
1340 #endif /* COMPAT_43 */
1341 
1342 		if ((oif_flags ^ ifp->if_flags) & IFF_UP) {
1343 #ifdef INET6
1344 			DELAY(100);/* XXX: temporary workaround for fxp issue*/
1345 			if (ifp->if_flags & IFF_UP) {
1346 				int s = splimp();
1347 				in6_if_up(ifp);
1348 				splx(s);
1349 			}
1350 #endif
1351 		}
1352 		return (error);
1353 
1354 	}
1355 	return (0);
1356 }
1357 
1358 /*
1359  * Set/clear promiscuous mode on interface ifp based on the truth value
1360  * of pswitch.  The calls are reference counted so that only the first
1361  * "on" request actually has an effect, as does the final "off" request.
1362  * Results are undefined if the "off" and "on" requests are not matched.
1363  */
1364 int
1365 ifpromisc(struct ifnet *ifp, int pswitch)
1366 {
1367 	struct ifreq ifr;
1368 	int error;
1369 	int oldflags;
1370 
1371 	oldflags = ifp->if_flags;
1372 	if (ifp->if_flags & IFF_PPROMISC) {
1373 		/* Do nothing if device is in permanently promiscuous mode */
1374 		ifp->if_pcount += pswitch ? 1 : -1;
1375 		return (0);
1376 	}
1377 	if (pswitch) {
1378 		/*
1379 		 * If the device is not configured up, we cannot put it in
1380 		 * promiscuous mode.
1381 		 */
1382 		if ((ifp->if_flags & IFF_UP) == 0)
1383 			return (ENETDOWN);
1384 		if (ifp->if_pcount++ != 0)
1385 			return (0);
1386 		ifp->if_flags |= IFF_PROMISC;
1387 		log(LOG_INFO, "%s: promiscuous mode enabled\n",
1388 		    ifp->if_xname);
1389 	} else {
1390 		if (--ifp->if_pcount > 0)
1391 			return (0);
1392 		ifp->if_flags &= ~IFF_PROMISC;
1393 		log(LOG_INFO, "%s: promiscuous mode disabled\n",
1394 		    ifp->if_xname);
1395 	}
1396 	ifr.ifr_flags = ifp->if_flags;
1397 	ifr.ifr_flagshigh = ifp->if_flags >> 16;
1398 	error = (*ifp->if_ioctl)(ifp, SIOCSIFFLAGS, (caddr_t)&ifr,
1399 				 (struct ucred *)NULL);
1400 	if (error == 0)
1401 		rt_ifmsg(ifp);
1402 	else
1403 		ifp->if_flags = oldflags;
1404 	return error;
1405 }
1406 
1407 /*
1408  * Return interface configuration
1409  * of system.  List may be used
1410  * in later ioctl's (above) to get
1411  * other information.
1412  */
1413 static int
1414 ifconf(u_long cmd, caddr_t data, struct thread *td)
1415 {
1416 	struct ifconf *ifc = (struct ifconf *)data;
1417 	struct ifnet *ifp;
1418 	struct ifaddr *ifa;
1419 	struct sockaddr *sa;
1420 	struct ifreq ifr, *ifrp;
1421 	int space = ifc->ifc_len, error = 0;
1422 
1423 	ifrp = ifc->ifc_req;
1424 	TAILQ_FOREACH(ifp, &ifnet, if_link) {
1425 		int addrs;
1426 
1427 		if (space <= sizeof ifr)
1428 			break;
1429 		if (strlcpy(ifr.ifr_name, ifp->if_xname, sizeof(ifr.ifr_name))
1430 		    >= sizeof(ifr.ifr_name)) {
1431 			error = ENAMETOOLONG;
1432 			break;
1433 		}
1434 
1435 		addrs = 0;
1436 		TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
1437 			if (space <= sizeof ifr)
1438 				break;
1439 			sa = ifa->ifa_addr;
1440 			if (td->td_proc->p_ucred->cr_prison &&
1441 			    prison_if(td, sa))
1442 				continue;
1443 			addrs++;
1444 #ifdef COMPAT_43
1445 			if (cmd == OSIOCGIFCONF) {
1446 				struct osockaddr *osa =
1447 					 (struct osockaddr *)&ifr.ifr_addr;
1448 				ifr.ifr_addr = *sa;
1449 				osa->sa_family = sa->sa_family;
1450 				error = copyout(&ifr, ifrp, sizeof ifr);
1451 				ifrp++;
1452 			} else
1453 #endif
1454 			if (sa->sa_len <= sizeof(*sa)) {
1455 				ifr.ifr_addr = *sa;
1456 				error = copyout(&ifr, ifrp, sizeof ifr);
1457 				ifrp++;
1458 			} else {
1459 				if (space < (sizeof ifr) + sa->sa_len -
1460 					    sizeof(*sa))
1461 					break;
1462 				space -= sa->sa_len - sizeof(*sa);
1463 				error = copyout(&ifr, ifrp,
1464 						sizeof ifr.ifr_name);
1465 				if (error == 0)
1466 					error = copyout(sa, &ifrp->ifr_addr,
1467 							sa->sa_len);
1468 				ifrp = (struct ifreq *)
1469 					(sa->sa_len + (caddr_t)&ifrp->ifr_addr);
1470 			}
1471 			if (error)
1472 				break;
1473 			space -= sizeof ifr;
1474 		}
1475 		if (error)
1476 			break;
1477 		if (!addrs) {
1478 			bzero(&ifr.ifr_addr, sizeof ifr.ifr_addr);
1479 			error = copyout(&ifr, ifrp, sizeof ifr);
1480 			if (error)
1481 				break;
1482 			space -= sizeof ifr;
1483 			ifrp++;
1484 		}
1485 	}
1486 	ifc->ifc_len -= space;
1487 	return (error);
1488 }
1489 
1490 /*
1491  * Just like if_promisc(), but for all-multicast-reception mode.
1492  */
1493 int
1494 if_allmulti(struct ifnet *ifp, int onswitch)
1495 {
1496 	int error = 0;
1497 	int s = splimp();
1498 	struct ifreq ifr;
1499 
1500 	if (onswitch) {
1501 		if (ifp->if_amcount++ == 0) {
1502 			ifp->if_flags |= IFF_ALLMULTI;
1503 			ifr.ifr_flags = ifp->if_flags;
1504 			ifr.ifr_flagshigh = ifp->if_flags >> 16;
1505 			error = ifp->if_ioctl(ifp, SIOCSIFFLAGS, (caddr_t)&ifr,
1506 					      (struct ucred *)NULL);
1507 		}
1508 	} else {
1509 		if (ifp->if_amcount > 1) {
1510 			ifp->if_amcount--;
1511 		} else {
1512 			ifp->if_amcount = 0;
1513 			ifp->if_flags &= ~IFF_ALLMULTI;
1514 			ifr.ifr_flags = ifp->if_flags;
1515 			ifr.ifr_flagshigh = ifp->if_flags >> 16;
1516 			error = ifp->if_ioctl(ifp, SIOCSIFFLAGS, (caddr_t)&ifr,
1517 					      (struct ucred *)NULL);
1518 		}
1519 	}
1520 	splx(s);
1521 
1522 	if (error == 0)
1523 		rt_ifmsg(ifp);
1524 	return error;
1525 }
1526 
1527 /*
1528  * Add a multicast listenership to the interface in question.
1529  * The link layer provides a routine which converts
1530  */
1531 int
1532 if_addmulti(
1533 	struct ifnet *ifp,	/* interface to manipulate */
1534 	struct sockaddr *sa,	/* address to add */
1535 	struct ifmultiaddr **retifma)
1536 {
1537 	struct sockaddr *llsa, *dupsa;
1538 	int error, s;
1539 	struct ifmultiaddr *ifma;
1540 
1541 	/*
1542 	 * If the matching multicast address already exists
1543 	 * then don't add a new one, just add a reference
1544 	 */
1545 	LIST_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
1546 		if (sa_equal(sa, ifma->ifma_addr)) {
1547 			ifma->ifma_refcount++;
1548 			if (retifma)
1549 				*retifma = ifma;
1550 			return 0;
1551 		}
1552 	}
1553 
1554 	/*
1555 	 * Give the link layer a chance to accept/reject it, and also
1556 	 * find out which AF_LINK address this maps to, if it isn't one
1557 	 * already.
1558 	 */
1559 	if (ifp->if_resolvemulti) {
1560 		error = ifp->if_resolvemulti(ifp, &llsa, sa);
1561 		if (error) return error;
1562 	} else {
1563 		llsa = 0;
1564 	}
1565 
1566 	MALLOC(ifma, struct ifmultiaddr *, sizeof *ifma, M_IFMADDR, M_WAITOK);
1567 	MALLOC(dupsa, struct sockaddr *, sa->sa_len, M_IFMADDR, M_WAITOK);
1568 	bcopy(sa, dupsa, sa->sa_len);
1569 
1570 	ifma->ifma_addr = dupsa;
1571 	ifma->ifma_lladdr = llsa;
1572 	ifma->ifma_ifp = ifp;
1573 	ifma->ifma_refcount = 1;
1574 	ifma->ifma_protospec = 0;
1575 	rt_newmaddrmsg(RTM_NEWMADDR, ifma);
1576 
1577 	/*
1578 	 * Some network interfaces can scan the address list at
1579 	 * interrupt time; lock them out.
1580 	 */
1581 	s = splimp();
1582 	LIST_INSERT_HEAD(&ifp->if_multiaddrs, ifma, ifma_link);
1583 	splx(s);
1584 	*retifma = ifma;
1585 
1586 	if (llsa != 0) {
1587 		LIST_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
1588 			if (sa_equal(ifma->ifma_addr, llsa))
1589 				break;
1590 		}
1591 		if (ifma) {
1592 			ifma->ifma_refcount++;
1593 		} else {
1594 			MALLOC(ifma, struct ifmultiaddr *, sizeof *ifma,
1595 			       M_IFMADDR, M_WAITOK);
1596 			MALLOC(dupsa, struct sockaddr *, llsa->sa_len,
1597 			       M_IFMADDR, M_WAITOK);
1598 			bcopy(llsa, dupsa, llsa->sa_len);
1599 			ifma->ifma_addr = dupsa;
1600 			ifma->ifma_ifp = ifp;
1601 			ifma->ifma_refcount = 1;
1602 			s = splimp();
1603 			LIST_INSERT_HEAD(&ifp->if_multiaddrs, ifma, ifma_link);
1604 			splx(s);
1605 		}
1606 	}
1607 	/*
1608 	 * We are certain we have added something, so call down to the
1609 	 * interface to let them know about it.
1610 	 */
1611 	s = splimp();
1612 	ifp->if_ioctl(ifp, SIOCADDMULTI, 0, (struct ucred *)NULL);
1613 	splx(s);
1614 
1615 	return 0;
1616 }
1617 
1618 /*
1619  * Remove a reference to a multicast address on this interface.  Yell
1620  * if the request does not match an existing membership.
1621  */
1622 int
1623 if_delmulti(struct ifnet *ifp, struct sockaddr *sa)
1624 {
1625 	struct ifmultiaddr *ifma;
1626 	int s;
1627 
1628 	LIST_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link)
1629 		if (sa_equal(sa, ifma->ifma_addr))
1630 			break;
1631 	if (ifma == 0)
1632 		return ENOENT;
1633 
1634 	if (ifma->ifma_refcount > 1) {
1635 		ifma->ifma_refcount--;
1636 		return 0;
1637 	}
1638 
1639 	rt_newmaddrmsg(RTM_DELMADDR, ifma);
1640 	sa = ifma->ifma_lladdr;
1641 	s = splimp();
1642 	LIST_REMOVE(ifma, ifma_link);
1643 	/*
1644 	 * Make sure the interface driver is notified
1645 	 * in the case of a link layer mcast group being left.
1646 	 */
1647 	if (ifma->ifma_addr->sa_family == AF_LINK && sa == 0)
1648 		ifp->if_ioctl(ifp, SIOCDELMULTI, 0, (struct ucred *)NULL);
1649 	splx(s);
1650 	free(ifma->ifma_addr, M_IFMADDR);
1651 	free(ifma, M_IFMADDR);
1652 	if (sa == 0)
1653 		return 0;
1654 
1655 	/*
1656 	 * Now look for the link-layer address which corresponds to
1657 	 * this network address.  It had been squirreled away in
1658 	 * ifma->ifma_lladdr for this purpose (so we don't have
1659 	 * to call ifp->if_resolvemulti() again), and we saved that
1660 	 * value in sa above.  If some nasty deleted the
1661 	 * link-layer address out from underneath us, we can deal because
1662 	 * the address we stored was is not the same as the one which was
1663 	 * in the record for the link-layer address.  (So we don't complain
1664 	 * in that case.)
1665 	 */
1666 	LIST_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link)
1667 		if (sa_equal(sa, ifma->ifma_addr))
1668 			break;
1669 	if (ifma == 0)
1670 		return 0;
1671 
1672 	if (ifma->ifma_refcount > 1) {
1673 		ifma->ifma_refcount--;
1674 		return 0;
1675 	}
1676 
1677 	s = splimp();
1678 	LIST_REMOVE(ifma, ifma_link);
1679 	ifp->if_ioctl(ifp, SIOCDELMULTI, 0, (struct ucred *)NULL);
1680 	splx(s);
1681 	free(ifma->ifma_addr, M_IFMADDR);
1682 	free(sa, M_IFMADDR);
1683 	free(ifma, M_IFMADDR);
1684 
1685 	return 0;
1686 }
1687 
1688 /*
1689  * Set the link layer address on an interface.
1690  *
1691  * At this time we only support certain types of interfaces,
1692  * and we don't allow the length of the address to change.
1693  */
1694 int
1695 if_setlladdr(struct ifnet *ifp, const u_char *lladdr, int len)
1696 {
1697 	struct sockaddr_dl *sdl;
1698 	struct ifaddr *ifa;
1699 	struct ifreq ifr;
1700 
1701 	ifa = ifnet_addrs[ifp->if_index - 1];
1702 	if (ifa == NULL)
1703 		return (EINVAL);
1704 	sdl = (struct sockaddr_dl *)ifa->ifa_addr;
1705 	if (sdl == NULL)
1706 		return (EINVAL);
1707 	if (len != sdl->sdl_alen)	/* don't allow length to change */
1708 		return (EINVAL);
1709 	switch (ifp->if_type) {
1710 	case IFT_ETHER:			/* these types use struct arpcom */
1711 	case IFT_FDDI:
1712 	case IFT_XETHER:
1713 	case IFT_ISO88025:
1714 	case IFT_L2VLAN:
1715 		bcopy(lladdr, ((struct arpcom *)ifp->if_softc)->ac_enaddr, len);
1716 		/* FALLTHROUGH */
1717 	case IFT_ARCNET:
1718 		bcopy(lladdr, LLADDR(sdl), len);
1719 		break;
1720 	default:
1721 		return (ENODEV);
1722 	}
1723 	/*
1724 	 * If the interface is already up, we need
1725 	 * to re-init it in order to reprogram its
1726 	 * address filter.
1727 	 */
1728 	if ((ifp->if_flags & IFF_UP) != 0) {
1729 		ifp->if_flags &= ~IFF_UP;
1730 		ifr.ifr_flags = ifp->if_flags;
1731 		ifr.ifr_flagshigh = ifp->if_flags >> 16;
1732 		(*ifp->if_ioctl)(ifp, SIOCSIFFLAGS, (caddr_t)&ifr,
1733 				 (struct ucred *)NULL);
1734 		ifp->if_flags |= IFF_UP;
1735 		ifr.ifr_flags = ifp->if_flags;
1736 		ifr.ifr_flagshigh = ifp->if_flags >> 16;
1737 		(*ifp->if_ioctl)(ifp, SIOCSIFFLAGS, (caddr_t)&ifr,
1738 				 (struct ucred *)NULL);
1739 #ifdef INET
1740 		/*
1741 		 * Also send gratuitous ARPs to notify other nodes about
1742 		 * the address change.
1743 		 */
1744 		TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
1745 			if (ifa->ifa_addr != NULL &&
1746 			    ifa->ifa_addr->sa_family == AF_INET)
1747 				arp_ifinit(ifp, ifa);
1748 		}
1749 #endif
1750 	}
1751 	return (0);
1752 }
1753 
1754 struct ifmultiaddr *
1755 ifmaof_ifpforaddr(struct sockaddr *sa, struct ifnet *ifp)
1756 {
1757 	struct ifmultiaddr *ifma;
1758 
1759 	LIST_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link)
1760 		if (sa_equal(ifma->ifma_addr, sa))
1761 			break;
1762 
1763 	return ifma;
1764 }
1765 
1766 /*
1767  * The name argument must be a pointer to storage which will last as
1768  * long as the interface does.  For physical devices, the result of
1769  * device_get_name(dev) is a good choice and for pseudo-devices a
1770  * static string works well.
1771  */
1772 void
1773 if_initname(struct ifnet *ifp, const char *name, int unit)
1774 {
1775 	ifp->if_dname = name;
1776 	ifp->if_dunit = unit;
1777 	if (unit != IF_DUNIT_NONE)
1778 		snprintf(ifp->if_xname, IFNAMSIZ, "%s%d", name, unit);
1779 	else
1780 		strlcpy(ifp->if_xname, name, IFNAMSIZ);
1781 }
1782 
1783 int
1784 if_printf(struct ifnet *ifp, const char *fmt, ...)
1785 {
1786 	__va_list ap;
1787 	int retval;
1788 
1789 	retval = printf("%s: ", ifp->if_xname);
1790 	__va_start(ap, fmt);
1791 	retval += vprintf(fmt, ap);
1792 	__va_end(ap);
1793 	return (retval);
1794 }
1795 
1796 SYSCTL_NODE(_net, PF_LINK, link, CTLFLAG_RW, 0, "Link layers");
1797 SYSCTL_NODE(_net_link, 0, generic, CTLFLAG_RW, 0, "Generic link-management");
1798 
1799 static int
1800 ifq_classic_enqueue(struct ifaltq *ifq, struct mbuf *m,
1801 		    struct altq_pktattr *pa __unused)
1802 {
1803 	if (IF_QFULL(ifq)) {
1804 		m_freem(m);
1805 		return(ENOBUFS);
1806 	} else {
1807 		IF_ENQUEUE(ifq, m);
1808 		return(0);
1809 	}
1810 }
1811 
1812 static struct mbuf *
1813 ifq_classic_dequeue(struct ifaltq *ifq, int op)
1814 {
1815 	struct mbuf *m;
1816 
1817 	switch (op) {
1818 	case ALTDQ_POLL:
1819 		IF_POLL(ifq, m);
1820 		break;
1821 	case ALTDQ_REMOVE:
1822 		IF_DEQUEUE(ifq, m);
1823 		break;
1824 	default:
1825 		panic("unsupported ALTQ dequeue op: %d", op);
1826 	}
1827 
1828 	return(m);
1829 }
1830 
1831 static int
1832 ifq_classic_request(struct ifaltq *ifq, int req, void *arg)
1833 {
1834 	switch (req) {
1835 	case ALTRQ_PURGE:
1836 		IF_DRAIN(ifq);
1837 		break;
1838 	default:
1839 		panic("unspported ALTQ request: %d", req);
1840 	}
1841 
1842 	return(0);
1843 }
1844