ifq.h revision 142564
1/*-
2 * Copyright (c) 1982, 1986, 1989, 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 * 4. Neither the name of the University 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 REGENTS 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 REGENTS 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 *	From: @(#)if.h	8.1 (Berkeley) 6/10/93
30 * $FreeBSD: head/sys/net/if_var.h 142564 2005-02-26 13:55:07Z glebius $
31 */
32
33#ifndef	_NET_IF_VAR_H_
34#define	_NET_IF_VAR_H_
35
36/*
37 * Structures defining a network interface, providing a packet
38 * transport mechanism (ala level 0 of the PUP protocols).
39 *
40 * Each interface accepts output datagrams of a specified maximum
41 * length, and provides higher level routines with input datagrams
42 * received from its medium.
43 *
44 * Output occurs when the routine if_output is called, with three parameters:
45 *	(*ifp->if_output)(ifp, m, dst, rt)
46 * Here m is the mbuf chain to be sent and dst is the destination address.
47 * The output routine encapsulates the supplied datagram if necessary,
48 * and then transmits it on its medium.
49 *
50 * On input, each interface unwraps the data received by it, and either
51 * places it on the input queue of an internetwork datagram routine
52 * and posts the associated software interrupt, or passes the datagram to a raw
53 * packet input routine.
54 *
55 * Routines exist for locating interfaces by their addresses
56 * or for locating an interface on a certain network, as well as more general
57 * routing and gateway routines maintaining information used to locate
58 * interfaces.  These routines live in the files if.c and route.c
59 */
60
61#ifdef __STDC__
62/*
63 * Forward structure declarations for function prototypes [sic].
64 */
65struct	mbuf;
66struct	thread;
67struct	rtentry;
68struct	rt_addrinfo;
69struct	socket;
70struct	ether_header;
71struct	carp_if;
72#endif
73
74#include <sys/queue.h>		/* get TAILQ macros */
75
76#ifdef _KERNEL
77#include <sys/mbuf.h>
78#include <sys/eventhandler.h>
79#endif /* _KERNEL */
80#include <sys/lock.h>		/* XXX */
81#include <sys/mutex.h>		/* XXX */
82#include <sys/event.h>		/* XXX */
83#include <sys/_task.h>
84
85#define	IF_DUNIT_NONE	-1
86
87#include <altq/if_altq.h>
88
89TAILQ_HEAD(ifnethead, ifnet);	/* we use TAILQs so that the order of */
90TAILQ_HEAD(ifaddrhead, ifaddr);	/* instantiation is preserved in the list */
91TAILQ_HEAD(ifprefixhead, ifprefix);
92TAILQ_HEAD(ifmultihead, ifmultiaddr);
93
94/*
95 * Structure defining a queue for a network interface.
96 */
97struct	ifqueue {
98	struct	mbuf *ifq_head;
99	struct	mbuf *ifq_tail;
100	int	ifq_len;
101	int	ifq_maxlen;
102	int	ifq_drops;
103	struct	mtx ifq_mtx;
104};
105
106/*
107 * Structure defining a network interface.
108 *
109 * (Would like to call this struct ``if'', but C isn't PL/1.)
110 */
111
112/*
113 * NB: For FreeBSD, it is assumed that each NIC driver's softc starts with
114 * one of these structures, typically held within an arpcom structure.
115 *
116 *	struct <foo>_softc {
117 *		struct arpcom {
118 *			struct  ifnet ac_if;
119 *			...
120 *		} <arpcom> ;
121 *		...
122 *	};
123 *
124 * The assumption is used in a number of places, including many
125 * files in sys/net, device drivers, and sys/dev/mii.c:miibus_attach().
126 *
127 * Unfortunately devices' softc are opaque, so we depend on this layout
128 * to locate the struct ifnet from the softc in the generic code.
129 *
130 */
131struct ifnet {
132	void	*if_softc;		/* pointer to driver state */
133	TAILQ_ENTRY(ifnet) if_link; 	/* all struct ifnets are chained */
134	char	if_xname[IFNAMSIZ];	/* external name (name + unit) */
135	const char *if_dname;		/* driver name */
136	int	if_dunit;		/* unit or IF_DUNIT_NONE */
137	struct	ifaddrhead if_addrhead;	/* linked list of addresses per if */
138		/*
139		 * if_addrhead is the list of all addresses associated to
140		 * an interface.
141		 * Some code in the kernel assumes that first element
142		 * of the list has type AF_LINK, and contains sockaddr_dl
143		 * addresses which store the link-level address and the name
144		 * of the interface.
145		 * However, access to the AF_LINK address through this
146		 * field is deprecated. Use ifaddr_byindex() instead.
147		 */
148	struct	knlist if_klist;	/* events attached to this if */
149	int	if_pcount;		/* number of promiscuous listeners */
150	union {
151		struct carp_if *carp_s;	/* carp structure (used by !carp ifs) */
152		struct ifnet *carp_d;	/* ptr to carpdev (used by carp ifs) */
153	} if_carp_ptr;
154#define	if_carp		if_carp_ptr.carp_s
155#define	if_carpdev	if_carp_ptr.carp_d
156	struct	bpf_if *if_bpf;		/* packet filter structure */
157	u_short	if_index;		/* numeric abbreviation for this if  */
158	short	if_timer;		/* time 'til if_watchdog called */
159	u_short	if_nvlans;		/* number of active vlans */
160	int	if_flags;		/* up/down, broadcast, etc. */
161	int	if_capabilities;	/* interface capabilities */
162	int	if_capenable;		/* enabled features */
163	void	*if_linkmib;		/* link-type-specific MIB data */
164	size_t	if_linkmiblen;		/* length of above data */
165	struct	if_data if_data;
166	struct	ifmultihead if_multiaddrs; /* multicast addresses configured */
167	int	if_amcount;		/* number of all-multicast requests */
168/* procedure handles */
169	int	(*if_output)		/* output routine (enqueue) */
170		(struct ifnet *, struct mbuf *, struct sockaddr *,
171		     struct rtentry *);
172	void	(*if_input)		/* input routine (from h/w driver) */
173		(struct ifnet *, struct mbuf *);
174	void	(*if_start)		/* initiate output routine */
175		(struct ifnet *);
176	int	(*if_ioctl)		/* ioctl routine */
177		(struct ifnet *, u_long, caddr_t);
178	void	(*if_watchdog)		/* timer routine */
179		(struct ifnet *);
180	void	(*if_init)		/* Init routine */
181		(void *);
182	int	(*if_resolvemulti)	/* validate/resolve multicast */
183		(struct ifnet *, struct sockaddr **, struct sockaddr *);
184	void	*if_spare1;		/* spare pointer 1 */
185	void	*if_spare2;		/* spare pointer 2 */
186	void	*if_spare3;		/* spare pointer 3 */
187	u_int	if_spare_flags1;	/* spare flags 1 */
188	u_int	if_spare_flags2;	/* spare flags 2 */
189	struct  ifaltq if_snd;		/* output queue (includes altq) */
190	const u_int8_t *if_broadcastaddr; /* linklevel broadcast bytestring */
191
192	struct	lltable *lltables;	/* list of L3-L2 resolution tables */
193
194	struct	label *if_label;	/* interface MAC label */
195
196	/* these are only used by IPv6 */
197	struct	ifprefixhead if_prefixhead; /* list of prefixes per if */
198	void	*if_afdata[AF_MAX];
199	int	if_afdata_initialized;
200	struct	mtx if_afdata_mtx;
201	struct	task if_starttask;	/* task for IFF_NEEDSGIANT */
202};
203
204typedef void if_init_f_t(void *);
205
206/*
207 * XXX These aliases are terribly dangerous because they could apply
208 * to anything.
209 */
210#define	if_mtu		if_data.ifi_mtu
211#define	if_type		if_data.ifi_type
212#define if_physical	if_data.ifi_physical
213#define	if_addrlen	if_data.ifi_addrlen
214#define	if_hdrlen	if_data.ifi_hdrlen
215#define	if_metric	if_data.ifi_metric
216#define	if_link_state	if_data.ifi_link_state
217#define	if_baudrate	if_data.ifi_baudrate
218#define	if_hwassist	if_data.ifi_hwassist
219#define	if_ipackets	if_data.ifi_ipackets
220#define	if_ierrors	if_data.ifi_ierrors
221#define	if_opackets	if_data.ifi_opackets
222#define	if_oerrors	if_data.ifi_oerrors
223#define	if_collisions	if_data.ifi_collisions
224#define	if_ibytes	if_data.ifi_ibytes
225#define	if_obytes	if_data.ifi_obytes
226#define	if_imcasts	if_data.ifi_imcasts
227#define	if_omcasts	if_data.ifi_omcasts
228#define	if_iqdrops	if_data.ifi_iqdrops
229#define	if_noproto	if_data.ifi_noproto
230#define	if_lastchange	if_data.ifi_lastchange
231#define if_recvquota	if_data.ifi_recvquota
232#define	if_xmitquota	if_data.ifi_xmitquota
233#define if_rawoutput(if, m, sa) if_output(if, m, sa, (struct rtentry *)NULL)
234
235/* for compatibility with other BSDs */
236#define	if_addrlist	if_addrhead
237#define	if_list		if_link
238
239/*
240 * Output queues (ifp->if_snd) and slow device input queues (*ifp->if_slowq)
241 * are queues of messages stored on ifqueue structures
242 * (defined above).  Entries are added to and deleted from these structures
243 * by these macros, which should be called with ipl raised to splimp().
244 */
245#define IF_LOCK(ifq)		mtx_lock(&(ifq)->ifq_mtx)
246#define IF_UNLOCK(ifq)		mtx_unlock(&(ifq)->ifq_mtx)
247#define	IF_LOCK_ASSERT(ifq)	mtx_assert(&(ifq)->ifq_mtx, MA_OWNED)
248#define	_IF_QFULL(ifq)		((ifq)->ifq_len >= (ifq)->ifq_maxlen)
249#define	_IF_DROP(ifq)		((ifq)->ifq_drops++)
250#define	_IF_QLEN(ifq)		((ifq)->ifq_len)
251
252#define	_IF_ENQUEUE(ifq, m) do { 				\
253	(m)->m_nextpkt = NULL;					\
254	if ((ifq)->ifq_tail == NULL) 				\
255		(ifq)->ifq_head = m; 				\
256	else 							\
257		(ifq)->ifq_tail->m_nextpkt = m; 		\
258	(ifq)->ifq_tail = m; 					\
259	(ifq)->ifq_len++; 					\
260} while (0)
261
262#define IF_ENQUEUE(ifq, m) do {					\
263	IF_LOCK(ifq); 						\
264	_IF_ENQUEUE(ifq, m); 					\
265	IF_UNLOCK(ifq); 					\
266} while (0)
267
268#define	_IF_PREPEND(ifq, m) do {				\
269	(m)->m_nextpkt = (ifq)->ifq_head; 			\
270	if ((ifq)->ifq_tail == NULL) 				\
271		(ifq)->ifq_tail = (m); 				\
272	(ifq)->ifq_head = (m); 					\
273	(ifq)->ifq_len++; 					\
274} while (0)
275
276#define IF_PREPEND(ifq, m) do {		 			\
277	IF_LOCK(ifq); 						\
278	_IF_PREPEND(ifq, m); 					\
279	IF_UNLOCK(ifq); 					\
280} while (0)
281
282#define	_IF_DEQUEUE(ifq, m) do { 				\
283	(m) = (ifq)->ifq_head; 					\
284	if (m) { 						\
285		if (((ifq)->ifq_head = (m)->m_nextpkt) == NULL)	\
286			(ifq)->ifq_tail = NULL; 		\
287		(m)->m_nextpkt = NULL; 				\
288		(ifq)->ifq_len--; 				\
289	} 							\
290} while (0)
291
292#define IF_DEQUEUE(ifq, m) do { 				\
293	IF_LOCK(ifq); 						\
294	_IF_DEQUEUE(ifq, m); 					\
295	IF_UNLOCK(ifq); 					\
296} while (0)
297
298#define	_IF_POLL(ifq, m)	((m) = (ifq)->ifq_head)
299#define	IF_POLL(ifq, m)		_IF_POLL(ifq, m)
300
301#define _IF_DRAIN(ifq) do { 					\
302	struct mbuf *m; 					\
303	for (;;) { 						\
304		_IF_DEQUEUE(ifq, m); 				\
305		if (m == NULL) 					\
306			break; 					\
307		m_freem(m); 					\
308	} 							\
309} while (0)
310
311#define IF_DRAIN(ifq) do {					\
312	IF_LOCK(ifq);						\
313	_IF_DRAIN(ifq);						\
314	IF_UNLOCK(ifq);						\
315} while(0)
316
317#ifdef _KERNEL
318/* interface address change event */
319typedef void (*ifaddr_event_handler_t)(void *, struct ifnet *);
320EVENTHANDLER_DECLARE(ifaddr_event, ifaddr_event_handler_t);
321/* new interface arrival event */
322typedef void (*ifnet_arrival_event_handler_t)(void *, struct ifnet *);
323EVENTHANDLER_DECLARE(ifnet_arrival_event, ifnet_arrival_event_handler_t);
324/* interface departure event */
325typedef void (*ifnet_departure_event_handler_t)(void *, struct ifnet *);
326EVENTHANDLER_DECLARE(ifnet_departure_event, ifnet_departure_event_handler_t);
327
328#define	IF_AFDATA_LOCK_INIT(ifp)	\
329    mtx_init(&(ifp)->if_afdata_mtx, "if_afdata", NULL, MTX_DEF)
330#define	IF_AFDATA_LOCK(ifp)	mtx_lock(&(ifp)->if_afdata_mtx)
331#define	IF_AFDATA_TRYLOCK(ifp)	mtx_trylock(&(ifp)->if_afdata_mtx)
332#define	IF_AFDATA_UNLOCK(ifp)	mtx_unlock(&(ifp)->if_afdata_mtx)
333#define	IF_AFDATA_DESTROY(ifp)	mtx_destroy(&(ifp)->if_afdata_mtx)
334
335#define	IFF_LOCKGIANT(ifp) do {						\
336	if ((ifp)->if_flags & IFF_NEEDSGIANT)				\
337		mtx_lock(&Giant);					\
338} while (0)
339
340#define	IFF_UNLOCKGIANT(ifp) do {					\
341	if ((ifp)->if_flags & IFF_NEEDSGIANT)				\
342		mtx_unlock(&Giant);					\
343} while (0)
344
345int	if_handoff(struct ifqueue *ifq, struct mbuf *m, struct ifnet *ifp,
346	    int adjust);
347#define	IF_HANDOFF(ifq, m, ifp)			\
348	if_handoff((struct ifqueue *)ifq, m, ifp, 0)
349#define	IF_HANDOFF_ADJ(ifq, m, ifp, adj)	\
350	if_handoff((struct ifqueue *)ifq, m, ifp, adj)
351
352void	if_start(struct ifnet *);
353
354#define	IFQ_ENQUEUE(ifq, m, err)					\
355do {									\
356	IF_LOCK(ifq);							\
357	if (ALTQ_IS_ENABLED(ifq))					\
358		ALTQ_ENQUEUE(ifq, m, NULL, err);			\
359	else {								\
360		if (_IF_QFULL(ifq)) {					\
361			m_freem(m);					\
362			(err) = ENOBUFS;				\
363		} else {						\
364			_IF_ENQUEUE(ifq, m);				\
365			(err) = 0;					\
366		}							\
367	}								\
368	if (err)							\
369		(ifq)->ifq_drops++;					\
370	IF_UNLOCK(ifq);							\
371} while (0)
372
373#define	IFQ_DEQUEUE_NOLOCK(ifq, m)					\
374do {									\
375	if (TBR_IS_ENABLED(ifq))					\
376		(m) = tbr_dequeue_ptr(ifq, ALTDQ_REMOVE);		\
377	else if (ALTQ_IS_ENABLED(ifq))					\
378		ALTQ_DEQUEUE(ifq, m);					\
379	else								\
380		_IF_DEQUEUE(ifq, m);					\
381} while (0)
382
383#define	IFQ_DEQUEUE(ifq, m)						\
384do {									\
385	IF_LOCK(ifq);							\
386	IFQ_DEQUEUE_NOLOCK(ifq, m);					\
387	IF_UNLOCK(ifq);							\
388} while (0)
389
390#define	IFQ_POLL_NOLOCK(ifq, m)						\
391do {									\
392	if (TBR_IS_ENABLED(ifq))					\
393		(m) = tbr_dequeue_ptr(ifq, ALTDQ_POLL);			\
394	else if (ALTQ_IS_ENABLED(ifq))					\
395		ALTQ_POLL(ifq, m);					\
396	else								\
397		_IF_POLL(ifq, m);					\
398} while (0)
399
400#define	IFQ_POLL(ifq, m)						\
401do {									\
402	IF_LOCK(ifq);							\
403	IFQ_POLL_NOLOCK(ifq, m);					\
404	IF_UNLOCK(ifq);							\
405} while (0)
406
407#define	IFQ_PURGE_NOLOCK(ifq)						\
408do {									\
409	if (ALTQ_IS_ENABLED(ifq)) {					\
410		ALTQ_PURGE(ifq);					\
411	} else								\
412		_IF_DRAIN(ifq);						\
413} while (0)
414
415#define	IFQ_PURGE(ifq)							\
416do {									\
417	IF_LOCK(ifq);							\
418	IFQ_PURGE_NOLOCK(ifq);						\
419	IF_UNLOCK(ifq);							\
420} while (0)
421
422#define	IFQ_SET_READY(ifq)						\
423	do { ((ifq)->altq_flags |= ALTQF_READY); } while (0)
424
425#define	IFQ_LOCK(ifq)			IF_LOCK(ifq)
426#define	IFQ_UNLOCK(ifq)			IF_UNLOCK(ifq)
427#define	IFQ_LOCK_ASSERT(ifq)		IF_LOCK_ASSERT(ifq)
428#define	IFQ_IS_EMPTY(ifq)		((ifq)->ifq_len == 0)
429#define	IFQ_INC_LEN(ifq)		((ifq)->ifq_len++)
430#define	IFQ_DEC_LEN(ifq)		(--(ifq)->ifq_len)
431#define	IFQ_INC_DROPS(ifq)		((ifq)->ifq_drops++)
432#define	IFQ_SET_MAXLEN(ifq, len)	((ifq)->ifq_maxlen = (len))
433
434#define	IFQ_HANDOFF_ADJ(ifp, m, adj, err)				\
435do {									\
436	int len;							\
437	short mflags;							\
438									\
439	len = (m)->m_pkthdr.len;					\
440	mflags = (m)->m_flags;						\
441	IFQ_ENQUEUE(&(ifp)->if_snd, m, err);				\
442	if ((err) == 0) {						\
443		(ifp)->if_obytes += len + (adj);			\
444		if (mflags & M_MCAST)					\
445			(ifp)->if_omcasts++;				\
446		if (((ifp)->if_flags & IFF_OACTIVE) == 0)		\
447			if_start(ifp);					\
448	}								\
449} while (0)
450
451#define	IFQ_HANDOFF(ifp, m, err)					\
452	IFQ_HANDOFF_ADJ(ifp, m, 0, err)
453
454#define	IFQ_DRV_DEQUEUE(ifq, m)						\
455do {									\
456	(m) = (ifq)->ifq_drv_head;					\
457	if (m) {							\
458		if (((ifq)->ifq_drv_head = (m)->m_nextpkt) == NULL)	\
459			(ifq)->ifq_drv_tail = NULL;			\
460		(m)->m_nextpkt = NULL;					\
461		(ifq)->ifq_drv_len--;					\
462	} else {							\
463		IFQ_LOCK(ifq);						\
464		IFQ_DEQUEUE_NOLOCK(ifq, m);				\
465		while ((ifq)->ifq_drv_len < (ifq)->ifq_drv_maxlen) {	\
466			struct mbuf *m0;				\
467			IFQ_DEQUEUE_NOLOCK(ifq, m0);			\
468			if (m0 == NULL)					\
469				break;					\
470			m0->m_nextpkt = NULL;				\
471			if ((ifq)->ifq_drv_tail == NULL)		\
472				(ifq)->ifq_drv_head = m0;		\
473			else						\
474				(ifq)->ifq_drv_tail->m_nextpkt = m0;	\
475			(ifq)->ifq_drv_tail = m0;			\
476			(ifq)->ifq_drv_len++;				\
477		}							\
478		IFQ_UNLOCK(ifq);					\
479	}								\
480} while (0)
481
482#define	IFQ_DRV_PREPEND(ifq, m)						\
483do {									\
484	(m)->m_nextpkt = (ifq)->ifq_drv_head;				\
485	if ((ifq)->ifq_drv_tail == NULL)				\
486		(ifq)->ifq_drv_tail = (m);				\
487	(ifq)->ifq_drv_head = (m);					\
488	(ifq)->ifq_drv_len++;						\
489} while (0)
490
491#define	IFQ_DRV_IS_EMPTY(ifq)						\
492	(((ifq)->ifq_drv_len == 0) && ((ifq)->ifq_len == 0))
493
494#define	IFQ_DRV_PURGE(ifq)						\
495do {									\
496	struct mbuf *m, *n = (ifq)->ifq_drv_head;			\
497	while((m = n) != NULL) {					\
498		n = m->m_nextpkt;					\
499		m_freem(m);						\
500	}								\
501	(ifq)->ifq_drv_head = (ifq)->ifq_drv_tail = NULL;		\
502	(ifq)->ifq_drv_len = 0;						\
503	IFQ_PURGE(ifq);							\
504} while (0)
505
506/*
507 * 72 was chosen below because it is the size of a TCP/IP
508 * header (40) + the minimum mss (32).
509 */
510#define	IF_MINMTU	72
511#define	IF_MAXMTU	65535
512
513#endif /* _KERNEL */
514
515/*
516 * The ifaddr structure contains information about one address
517 * of an interface.  They are maintained by the different address families,
518 * are allocated and attached when an address is set, and are linked
519 * together so all addresses for an interface can be located.
520 *
521 * NOTE: a 'struct ifaddr' is always at the beginning of a larger
522 * chunk of malloc'ed memory, where we store the three addresses
523 * (ifa_addr, ifa_dstaddr and ifa_netmask) referenced here.
524 */
525struct ifaddr {
526	struct	sockaddr *ifa_addr;	/* address of interface */
527	struct	sockaddr *ifa_dstaddr;	/* other end of p-to-p link */
528#define	ifa_broadaddr	ifa_dstaddr	/* broadcast address interface */
529	struct	sockaddr *ifa_netmask;	/* used to determine subnet */
530	struct	if_data if_data;	/* not all members are meaningful */
531	struct	ifnet *ifa_ifp;		/* back-pointer to interface */
532	TAILQ_ENTRY(ifaddr) ifa_link;	/* queue macro glue */
533	void	(*ifa_rtrequest)	/* check or clean routes (+ or -)'d */
534		(int, struct rtentry *, struct rt_addrinfo *);
535	u_short	ifa_flags;		/* mostly rt_flags for cloning */
536	u_int	ifa_refcnt;		/* references to this structure */
537	int	ifa_metric;		/* cost of going out this interface */
538	int (*ifa_claim_addr)		/* check if an addr goes to this if */
539		(struct ifaddr *, struct sockaddr *);
540	struct mtx ifa_mtx;
541};
542#define	IFA_ROUTE	RTF_UP		/* route installed */
543
544/* for compatibility with other BSDs */
545#define	ifa_list	ifa_link
546
547#define	IFA_LOCK_INIT(ifa)	\
548    mtx_init(&(ifa)->ifa_mtx, "ifaddr", NULL, MTX_DEF)
549#define	IFA_LOCK(ifa)		mtx_lock(&(ifa)->ifa_mtx)
550#define	IFA_UNLOCK(ifa)		mtx_unlock(&(ifa)->ifa_mtx)
551#define	IFA_DESTROY(ifa)	mtx_destroy(&(ifa)->ifa_mtx)
552
553/*
554 * The prefix structure contains information about one prefix
555 * of an interface.  They are maintained by the different address families,
556 * are allocated and attached when a prefix or an address is set,
557 * and are linked together so all prefixes for an interface can be located.
558 */
559struct ifprefix {
560	struct	sockaddr *ifpr_prefix;	/* prefix of interface */
561	struct	ifnet *ifpr_ifp;	/* back-pointer to interface */
562	TAILQ_ENTRY(ifprefix) ifpr_list; /* queue macro glue */
563	u_char	ifpr_plen;		/* prefix length in bits */
564	u_char	ifpr_type;		/* protocol dependent prefix type */
565};
566
567/*
568 * Multicast address structure.  This is analogous to the ifaddr
569 * structure except that it keeps track of multicast addresses.
570 * Also, the reference count here is a count of requests for this
571 * address, not a count of pointers to this structure.
572 */
573struct ifmultiaddr {
574	TAILQ_ENTRY(ifmultiaddr) ifma_link; /* queue macro glue */
575	struct	sockaddr *ifma_addr; 	/* address this membership is for */
576	struct	sockaddr *ifma_lladdr;	/* link-layer translation, if any */
577	struct	ifnet *ifma_ifp;	/* back-pointer to interface */
578	u_int	ifma_refcount;		/* reference count */
579	void	*ifma_protospec;	/* protocol-specific state, if any */
580};
581
582#ifdef _KERNEL
583#define	IFAFREE(ifa)					\
584	do {						\
585		IFA_LOCK(ifa);				\
586		KASSERT((ifa)->ifa_refcnt > 0,		\
587		    ("ifa %p !(ifa_refcnt > 0)", ifa));	\
588		if (--(ifa)->ifa_refcnt == 0) {		\
589			IFA_DESTROY(ifa);		\
590			free(ifa, M_IFADDR);		\
591		} else 					\
592			IFA_UNLOCK(ifa);		\
593	} while (0)
594
595#define IFAREF(ifa)					\
596	do {						\
597		IFA_LOCK(ifa);				\
598		++(ifa)->ifa_refcnt;			\
599		IFA_UNLOCK(ifa);			\
600	} while (0)
601
602extern	struct mtx ifnet_lock;
603#define	IFNET_LOCK_INIT() \
604    mtx_init(&ifnet_lock, "ifnet", NULL, MTX_DEF | MTX_RECURSE)
605#define	IFNET_WLOCK()		mtx_lock(&ifnet_lock)
606#define	IFNET_WUNLOCK()		mtx_unlock(&ifnet_lock)
607#define	IFNET_RLOCK()		IFNET_WLOCK()
608#define	IFNET_RUNLOCK()		IFNET_WUNLOCK()
609
610struct ifindex_entry {
611	struct	ifnet *ife_ifnet;
612	struct	ifaddr *ife_ifnet_addr;
613	struct cdev *ife_dev;
614};
615
616#define ifnet_byindex(idx)	ifindex_table[(idx)].ife_ifnet
617/*
618 * Given the index, ifaddr_byindex() returns the one and only
619 * link-level ifaddr for the interface. You are not supposed to use
620 * it to traverse the list of addresses associated to the interface.
621 */
622#define ifaddr_byindex(idx)	ifindex_table[(idx)].ife_ifnet_addr
623#define ifdev_byindex(idx)	ifindex_table[(idx)].ife_dev
624
625extern	struct ifnethead ifnet;
626extern	struct ifindex_entry *ifindex_table;
627extern	int ifqmaxlen;
628extern	struct ifnet *loif;	/* first loopback interface */
629extern	int if_index;
630
631int	if_addmulti(struct ifnet *, struct sockaddr *, struct ifmultiaddr **);
632int	if_allmulti(struct ifnet *, int);
633void	if_attach(struct ifnet *);
634int	if_delmulti(struct ifnet *, struct sockaddr *);
635void	if_detach(struct ifnet *);
636void	if_down(struct ifnet *);
637void	if_initname(struct ifnet *, const char *, int);
638void	if_link_state_change(struct ifnet *, int);
639int	if_printf(struct ifnet *, const char *, ...) __printflike(2, 3);
640int	if_setlladdr(struct ifnet *, const u_char *, int);
641void	if_up(struct ifnet *);
642/*void	ifinit(void);*/ /* declared in systm.h for main() */
643int	ifioctl(struct socket *, u_long, caddr_t, struct thread *);
644int	ifpromisc(struct ifnet *, int);
645struct	ifnet *ifunit(const char *);
646
647struct	ifaddr *ifa_ifwithaddr(struct sockaddr *);
648struct	ifaddr *ifa_ifwithdstaddr(struct sockaddr *);
649struct	ifaddr *ifa_ifwithnet(struct sockaddr *);
650struct	ifaddr *ifa_ifwithroute(int, struct sockaddr *, struct sockaddr *);
651struct	ifaddr *ifaof_ifpforaddr(struct sockaddr *, struct ifnet *);
652
653struct	ifmultiaddr *ifmaof_ifpforaddr(struct sockaddr *, struct ifnet *);
654int	if_simloop(struct ifnet *ifp, struct mbuf *m, int af, int hlen);
655
656#define IF_LLADDR(ifp)							\
657    LLADDR((struct sockaddr_dl *) ifaddr_byindex((ifp)->if_index)->ifa_addr)
658
659#ifdef DEVICE_POLLING
660enum poll_cmd {	POLL_ONLY, POLL_AND_CHECK_STATUS, POLL_DEREGISTER };
661
662typedef	void poll_handler_t(struct ifnet *ifp, enum poll_cmd cmd, int count);
663int    ether_poll_register(poll_handler_t *h, struct ifnet *ifp);
664int    ether_poll_deregister(struct ifnet *ifp);
665#endif /* DEVICE_POLLING */
666
667#endif /* _KERNEL */
668
669#endif /* !_NET_IF_VAR_H_ */
670