ifq.h revision 155051
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 155051 2006-01-30 13:45:15Z 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;
72struct  ifvlantrunk;
73#endif
74
75#include <sys/queue.h>		/* get TAILQ macros */
76
77#ifdef _KERNEL
78#include <sys/mbuf.h>
79#include <sys/eventhandler.h>
80#endif /* _KERNEL */
81#include <sys/lock.h>		/* XXX */
82#include <sys/mutex.h>		/* XXX */
83#include <sys/event.h>		/* XXX */
84#include <sys/_task.h>
85
86#define	IF_DUNIT_NONE	-1
87
88#include <altq/if_altq.h>
89
90TAILQ_HEAD(ifnethead, ifnet);	/* we use TAILQs so that the order of */
91TAILQ_HEAD(ifaddrhead, ifaddr);	/* instantiation is preserved in the list */
92TAILQ_HEAD(ifprefixhead, ifprefix);
93TAILQ_HEAD(ifmultihead, ifmultiaddr);
94
95/*
96 * Structure defining a queue for a network interface.
97 */
98struct	ifqueue {
99	struct	mbuf *ifq_head;
100	struct	mbuf *ifq_tail;
101	int	ifq_len;
102	int	ifq_maxlen;
103	int	ifq_drops;
104	struct	mtx ifq_mtx;
105};
106
107/*
108 * Structure defining a network interface.
109 *
110 * (Would like to call this struct ``if'', but C isn't PL/1.)
111 */
112
113struct ifnet {
114	void	*if_softc;		/* pointer to driver state */
115	void	*if_l2com;		/* pointer to protocol bits */
116	TAILQ_ENTRY(ifnet) if_link; 	/* all struct ifnets are chained */
117	char	if_xname[IFNAMSIZ];	/* external name (name + unit) */
118	const char *if_dname;		/* driver name */
119	int	if_dunit;		/* unit or IF_DUNIT_NONE */
120	struct	ifaddrhead if_addrhead;	/* linked list of addresses per if */
121		/*
122		 * if_addrhead is the list of all addresses associated to
123		 * an interface.
124		 * Some code in the kernel assumes that first element
125		 * of the list has type AF_LINK, and contains sockaddr_dl
126		 * addresses which store the link-level address and the name
127		 * of the interface.
128		 * However, access to the AF_LINK address through this
129		 * field is deprecated. Use if_addr or ifaddr_byindex() instead.
130		 */
131	struct	knlist if_klist;	/* events attached to this if */
132	int	if_pcount;		/* number of promiscuous listeners */
133	struct	carp_if *if_carp;	/* carp interface structure */
134	struct	bpf_if *if_bpf;		/* packet filter structure */
135	u_short	if_index;		/* numeric abbreviation for this if  */
136	short	if_timer;		/* time 'til if_watchdog called */
137	struct  ifvlantrunk *if_vlantrunk; /* pointer to 802.1q data */
138	int	if_flags;		/* up/down, broadcast, etc. */
139	int	if_capabilities;	/* interface capabilities */
140	int	if_capenable;		/* enabled features */
141	void	*if_linkmib;		/* link-type-specific MIB data */
142	size_t	if_linkmiblen;		/* length of above data */
143	struct	if_data if_data;
144	struct	ifmultihead if_multiaddrs; /* multicast addresses configured */
145	int	if_amcount;		/* number of all-multicast requests */
146/* procedure handles */
147	int	(*if_output)		/* output routine (enqueue) */
148		(struct ifnet *, struct mbuf *, struct sockaddr *,
149		     struct rtentry *);
150	void	(*if_input)		/* input routine (from h/w driver) */
151		(struct ifnet *, struct mbuf *);
152	void	(*if_start)		/* initiate output routine */
153		(struct ifnet *);
154	int	(*if_ioctl)		/* ioctl routine */
155		(struct ifnet *, u_long, caddr_t);
156	void	(*if_watchdog)		/* timer routine */
157		(struct ifnet *);
158	void	(*if_init)		/* Init routine */
159		(void *);
160	int	(*if_resolvemulti)	/* validate/resolve multicast */
161		(struct ifnet *, struct sockaddr **, struct sockaddr *);
162	struct	ifaddr	*if_addr;	/* pointer to link-level address */
163	void	*if_spare2;		/* spare pointer 2 */
164	void	*if_spare3;		/* spare pointer 3 */
165	int	if_drv_flags;		/* driver-managed status flags */
166	u_int	if_spare_flags2;	/* spare flags 2 */
167	struct  ifaltq if_snd;		/* output queue (includes altq) */
168	const u_int8_t *if_broadcastaddr; /* linklevel broadcast bytestring */
169
170	void	*if_bridge;		/* bridge glue */
171
172	struct	lltable *lltables;	/* list of L3-L2 resolution tables */
173
174	struct	label *if_label;	/* interface MAC label */
175
176	/* these are only used by IPv6 */
177	struct	ifprefixhead if_prefixhead; /* list of prefixes per if */
178	void	*if_afdata[AF_MAX];
179	int	if_afdata_initialized;
180	struct	mtx if_afdata_mtx;
181	struct	task if_starttask;	/* task for IFF_NEEDSGIANT */
182	struct	task if_linktask;	/* task for link change events */
183	struct	mtx if_addr_mtx;	/* mutex to protect address lists */
184	LIST_ENTRY(ifnet) if_clones;	/* interfaces of a cloner */
185};
186
187typedef void if_init_f_t(void *);
188
189/*
190 * XXX These aliases are terribly dangerous because they could apply
191 * to anything.
192 */
193#define	if_mtu		if_data.ifi_mtu
194#define	if_type		if_data.ifi_type
195#define if_physical	if_data.ifi_physical
196#define	if_addrlen	if_data.ifi_addrlen
197#define	if_hdrlen	if_data.ifi_hdrlen
198#define	if_metric	if_data.ifi_metric
199#define	if_link_state	if_data.ifi_link_state
200#define	if_baudrate	if_data.ifi_baudrate
201#define	if_hwassist	if_data.ifi_hwassist
202#define	if_ipackets	if_data.ifi_ipackets
203#define	if_ierrors	if_data.ifi_ierrors
204#define	if_opackets	if_data.ifi_opackets
205#define	if_oerrors	if_data.ifi_oerrors
206#define	if_collisions	if_data.ifi_collisions
207#define	if_ibytes	if_data.ifi_ibytes
208#define	if_obytes	if_data.ifi_obytes
209#define	if_imcasts	if_data.ifi_imcasts
210#define	if_omcasts	if_data.ifi_omcasts
211#define	if_iqdrops	if_data.ifi_iqdrops
212#define	if_noproto	if_data.ifi_noproto
213#define	if_lastchange	if_data.ifi_lastchange
214#define if_recvquota	if_data.ifi_recvquota
215#define	if_xmitquota	if_data.ifi_xmitquota
216#define if_rawoutput(if, m, sa) if_output(if, m, sa, (struct rtentry *)NULL)
217
218/* for compatibility with other BSDs */
219#define	if_addrlist	if_addrhead
220#define	if_list		if_link
221
222/*
223 * Locks for address lists on the network interface.
224 */
225#define	IF_ADDR_LOCK_INIT(if)	mtx_init(&(if)->if_addr_mtx,		\
226				    "if_addr_mtx", NULL, MTX_DEF)
227#define	IF_ADDR_LOCK_DESTROY(if)	mtx_destroy(&(if)->if_addr_mtx)
228#define	IF_ADDR_LOCK(if)	mtx_lock(&(if)->if_addr_mtx)
229#define	IF_ADDR_UNLOCK(if)	mtx_unlock(&(if)->if_addr_mtx)
230#define	IF_ADDR_LOCK_ASSERT(if)	mtx_assert(&(if)->if_addr_mtx, MA_OWNED)
231
232/*
233 * Output queues (ifp->if_snd) and slow device input queues (*ifp->if_slowq)
234 * are queues of messages stored on ifqueue structures
235 * (defined above).  Entries are added to and deleted from these structures
236 * by these macros, which should be called with ipl raised to splimp().
237 */
238#define IF_LOCK(ifq)		mtx_lock(&(ifq)->ifq_mtx)
239#define IF_UNLOCK(ifq)		mtx_unlock(&(ifq)->ifq_mtx)
240#define	IF_LOCK_ASSERT(ifq)	mtx_assert(&(ifq)->ifq_mtx, MA_OWNED)
241#define	_IF_QFULL(ifq)		((ifq)->ifq_len >= (ifq)->ifq_maxlen)
242#define	_IF_DROP(ifq)		((ifq)->ifq_drops++)
243#define	_IF_QLEN(ifq)		((ifq)->ifq_len)
244
245#define	_IF_ENQUEUE(ifq, m) do { 				\
246	(m)->m_nextpkt = NULL;					\
247	if ((ifq)->ifq_tail == NULL) 				\
248		(ifq)->ifq_head = m; 				\
249	else 							\
250		(ifq)->ifq_tail->m_nextpkt = m; 		\
251	(ifq)->ifq_tail = m; 					\
252	(ifq)->ifq_len++; 					\
253} while (0)
254
255#define IF_ENQUEUE(ifq, m) do {					\
256	IF_LOCK(ifq); 						\
257	_IF_ENQUEUE(ifq, m); 					\
258	IF_UNLOCK(ifq); 					\
259} while (0)
260
261#define	_IF_PREPEND(ifq, m) do {				\
262	(m)->m_nextpkt = (ifq)->ifq_head; 			\
263	if ((ifq)->ifq_tail == NULL) 				\
264		(ifq)->ifq_tail = (m); 				\
265	(ifq)->ifq_head = (m); 					\
266	(ifq)->ifq_len++; 					\
267} while (0)
268
269#define IF_PREPEND(ifq, m) do {		 			\
270	IF_LOCK(ifq); 						\
271	_IF_PREPEND(ifq, m); 					\
272	IF_UNLOCK(ifq); 					\
273} while (0)
274
275#define	_IF_DEQUEUE(ifq, m) do { 				\
276	(m) = (ifq)->ifq_head; 					\
277	if (m) { 						\
278		if (((ifq)->ifq_head = (m)->m_nextpkt) == NULL)	\
279			(ifq)->ifq_tail = NULL; 		\
280		(m)->m_nextpkt = NULL; 				\
281		(ifq)->ifq_len--; 				\
282	} 							\
283} while (0)
284
285#define IF_DEQUEUE(ifq, m) do { 				\
286	IF_LOCK(ifq); 						\
287	_IF_DEQUEUE(ifq, m); 					\
288	IF_UNLOCK(ifq); 					\
289} while (0)
290
291#define	_IF_POLL(ifq, m)	((m) = (ifq)->ifq_head)
292#define	IF_POLL(ifq, m)		_IF_POLL(ifq, m)
293
294#define _IF_DRAIN(ifq) do { 					\
295	struct mbuf *m; 					\
296	for (;;) { 						\
297		_IF_DEQUEUE(ifq, m); 				\
298		if (m == NULL) 					\
299			break; 					\
300		m_freem(m); 					\
301	} 							\
302} while (0)
303
304#define IF_DRAIN(ifq) do {					\
305	IF_LOCK(ifq);						\
306	_IF_DRAIN(ifq);						\
307	IF_UNLOCK(ifq);						\
308} while(0)
309
310#ifdef _KERNEL
311/* interface address change event */
312typedef void (*ifaddr_event_handler_t)(void *, struct ifnet *);
313EVENTHANDLER_DECLARE(ifaddr_event, ifaddr_event_handler_t);
314/* new interface arrival event */
315typedef void (*ifnet_arrival_event_handler_t)(void *, struct ifnet *);
316EVENTHANDLER_DECLARE(ifnet_arrival_event, ifnet_arrival_event_handler_t);
317/* interface departure event */
318typedef void (*ifnet_departure_event_handler_t)(void *, struct ifnet *);
319EVENTHANDLER_DECLARE(ifnet_departure_event, ifnet_departure_event_handler_t);
320
321#define	IF_AFDATA_LOCK_INIT(ifp)	\
322    mtx_init(&(ifp)->if_afdata_mtx, "if_afdata", NULL, MTX_DEF)
323#define	IF_AFDATA_LOCK(ifp)	mtx_lock(&(ifp)->if_afdata_mtx)
324#define	IF_AFDATA_TRYLOCK(ifp)	mtx_trylock(&(ifp)->if_afdata_mtx)
325#define	IF_AFDATA_UNLOCK(ifp)	mtx_unlock(&(ifp)->if_afdata_mtx)
326#define	IF_AFDATA_DESTROY(ifp)	mtx_destroy(&(ifp)->if_afdata_mtx)
327
328#define	IFF_LOCKGIANT(ifp) do {						\
329	if ((ifp)->if_flags & IFF_NEEDSGIANT)				\
330		mtx_lock(&Giant);					\
331} while (0)
332
333#define	IFF_UNLOCKGIANT(ifp) do {					\
334	if ((ifp)->if_flags & IFF_NEEDSGIANT)				\
335		mtx_unlock(&Giant);					\
336} while (0)
337
338int	if_handoff(struct ifqueue *ifq, struct mbuf *m, struct ifnet *ifp,
339	    int adjust);
340#define	IF_HANDOFF(ifq, m, ifp)			\
341	if_handoff((struct ifqueue *)ifq, m, ifp, 0)
342#define	IF_HANDOFF_ADJ(ifq, m, ifp, adj)	\
343	if_handoff((struct ifqueue *)ifq, m, ifp, adj)
344
345void	if_start(struct ifnet *);
346
347#define	IFQ_ENQUEUE(ifq, m, err)					\
348do {									\
349	IF_LOCK(ifq);							\
350	if (ALTQ_IS_ENABLED(ifq))					\
351		ALTQ_ENQUEUE(ifq, m, NULL, err);			\
352	else {								\
353		if (_IF_QFULL(ifq)) {					\
354			m_freem(m);					\
355			(err) = ENOBUFS;				\
356		} else {						\
357			_IF_ENQUEUE(ifq, m);				\
358			(err) = 0;					\
359		}							\
360	}								\
361	if (err)							\
362		(ifq)->ifq_drops++;					\
363	IF_UNLOCK(ifq);							\
364} while (0)
365
366#define	IFQ_DEQUEUE_NOLOCK(ifq, m)					\
367do {									\
368	if (TBR_IS_ENABLED(ifq))					\
369		(m) = tbr_dequeue_ptr(ifq, ALTDQ_REMOVE);		\
370	else if (ALTQ_IS_ENABLED(ifq))					\
371		ALTQ_DEQUEUE(ifq, m);					\
372	else								\
373		_IF_DEQUEUE(ifq, m);					\
374} while (0)
375
376#define	IFQ_DEQUEUE(ifq, m)						\
377do {									\
378	IF_LOCK(ifq);							\
379	IFQ_DEQUEUE_NOLOCK(ifq, m);					\
380	IF_UNLOCK(ifq);							\
381} while (0)
382
383#define	IFQ_POLL_NOLOCK(ifq, m)						\
384do {									\
385	if (TBR_IS_ENABLED(ifq))					\
386		(m) = tbr_dequeue_ptr(ifq, ALTDQ_POLL);			\
387	else if (ALTQ_IS_ENABLED(ifq))					\
388		ALTQ_POLL(ifq, m);					\
389	else								\
390		_IF_POLL(ifq, m);					\
391} while (0)
392
393#define	IFQ_POLL(ifq, m)						\
394do {									\
395	IF_LOCK(ifq);							\
396	IFQ_POLL_NOLOCK(ifq, m);					\
397	IF_UNLOCK(ifq);							\
398} while (0)
399
400#define	IFQ_PURGE_NOLOCK(ifq)						\
401do {									\
402	if (ALTQ_IS_ENABLED(ifq)) {					\
403		ALTQ_PURGE(ifq);					\
404	} else								\
405		_IF_DRAIN(ifq);						\
406} while (0)
407
408#define	IFQ_PURGE(ifq)							\
409do {									\
410	IF_LOCK(ifq);							\
411	IFQ_PURGE_NOLOCK(ifq);						\
412	IF_UNLOCK(ifq);							\
413} while (0)
414
415#define	IFQ_SET_READY(ifq)						\
416	do { ((ifq)->altq_flags |= ALTQF_READY); } while (0)
417
418#define	IFQ_LOCK(ifq)			IF_LOCK(ifq)
419#define	IFQ_UNLOCK(ifq)			IF_UNLOCK(ifq)
420#define	IFQ_LOCK_ASSERT(ifq)		IF_LOCK_ASSERT(ifq)
421#define	IFQ_IS_EMPTY(ifq)		((ifq)->ifq_len == 0)
422#define	IFQ_INC_LEN(ifq)		((ifq)->ifq_len++)
423#define	IFQ_DEC_LEN(ifq)		(--(ifq)->ifq_len)
424#define	IFQ_INC_DROPS(ifq)		((ifq)->ifq_drops++)
425#define	IFQ_SET_MAXLEN(ifq, len)	((ifq)->ifq_maxlen = (len))
426
427/*
428 * The IFF_DRV_OACTIVE test should really occur in the device driver, not in
429 * the handoff logic, as that flag is locked by the device driver.
430 */
431#define	IFQ_HANDOFF_ADJ(ifp, m, adj, err)				\
432do {									\
433	int len;							\
434	short mflags;							\
435									\
436	len = (m)->m_pkthdr.len;					\
437	mflags = (m)->m_flags;						\
438	IFQ_ENQUEUE(&(ifp)->if_snd, m, err);				\
439	if ((err) == 0) {						\
440		(ifp)->if_obytes += len + (adj);			\
441		if (mflags & M_MCAST)					\
442			(ifp)->if_omcasts++;				\
443		if (((ifp)->if_drv_flags & IFF_DRV_OACTIVE) == 0)	\
444			if_start(ifp);					\
445	}								\
446} while (0)
447
448#define	IFQ_HANDOFF(ifp, m, err)					\
449	IFQ_HANDOFF_ADJ(ifp, m, 0, err)
450
451#define	IFQ_DRV_DEQUEUE(ifq, m)						\
452do {									\
453	(m) = (ifq)->ifq_drv_head;					\
454	if (m) {							\
455		if (((ifq)->ifq_drv_head = (m)->m_nextpkt) == NULL)	\
456			(ifq)->ifq_drv_tail = NULL;			\
457		(m)->m_nextpkt = NULL;					\
458		(ifq)->ifq_drv_len--;					\
459	} else {							\
460		IFQ_LOCK(ifq);						\
461		IFQ_DEQUEUE_NOLOCK(ifq, m);				\
462		while ((ifq)->ifq_drv_len < (ifq)->ifq_drv_maxlen) {	\
463			struct mbuf *m0;				\
464			IFQ_DEQUEUE_NOLOCK(ifq, m0);			\
465			if (m0 == NULL)					\
466				break;					\
467			m0->m_nextpkt = NULL;				\
468			if ((ifq)->ifq_drv_tail == NULL)		\
469				(ifq)->ifq_drv_head = m0;		\
470			else						\
471				(ifq)->ifq_drv_tail->m_nextpkt = m0;	\
472			(ifq)->ifq_drv_tail = m0;			\
473			(ifq)->ifq_drv_len++;				\
474		}							\
475		IFQ_UNLOCK(ifq);					\
476	}								\
477} while (0)
478
479#define	IFQ_DRV_PREPEND(ifq, m)						\
480do {									\
481	(m)->m_nextpkt = (ifq)->ifq_drv_head;				\
482	if ((ifq)->ifq_drv_tail == NULL)				\
483		(ifq)->ifq_drv_tail = (m);				\
484	(ifq)->ifq_drv_head = (m);					\
485	(ifq)->ifq_drv_len++;						\
486} while (0)
487
488#define	IFQ_DRV_IS_EMPTY(ifq)						\
489	(((ifq)->ifq_drv_len == 0) && ((ifq)->ifq_len == 0))
490
491#define	IFQ_DRV_PURGE(ifq)						\
492do {									\
493	struct mbuf *m, *n = (ifq)->ifq_drv_head;			\
494	while((m = n) != NULL) {					\
495		n = m->m_nextpkt;					\
496		m_freem(m);						\
497	}								\
498	(ifq)->ifq_drv_head = (ifq)->ifq_drv_tail = NULL;		\
499	(ifq)->ifq_drv_len = 0;						\
500	IFQ_PURGE(ifq);							\
501} while (0)
502
503/*
504 * 72 was chosen below because it is the size of a TCP/IP
505 * header (40) + the minimum mss (32).
506 */
507#define	IF_MINMTU	72
508#define	IF_MAXMTU	65535
509
510#endif /* _KERNEL */
511
512/*
513 * The ifaddr structure contains information about one address
514 * of an interface.  They are maintained by the different address families,
515 * are allocated and attached when an address is set, and are linked
516 * together so all addresses for an interface can be located.
517 *
518 * NOTE: a 'struct ifaddr' is always at the beginning of a larger
519 * chunk of malloc'ed memory, where we store the three addresses
520 * (ifa_addr, ifa_dstaddr and ifa_netmask) referenced here.
521 */
522struct ifaddr {
523	struct	sockaddr *ifa_addr;	/* address of interface */
524	struct	sockaddr *ifa_dstaddr;	/* other end of p-to-p link */
525#define	ifa_broadaddr	ifa_dstaddr	/* broadcast address interface */
526	struct	sockaddr *ifa_netmask;	/* used to determine subnet */
527	struct	if_data if_data;	/* not all members are meaningful */
528	struct	ifnet *ifa_ifp;		/* back-pointer to interface */
529	TAILQ_ENTRY(ifaddr) ifa_link;	/* queue macro glue */
530	void	(*ifa_rtrequest)	/* check or clean routes (+ or -)'d */
531		(int, struct rtentry *, struct rt_addrinfo *);
532	u_short	ifa_flags;		/* mostly rt_flags for cloning */
533	u_int	ifa_refcnt;		/* references to this structure */
534	int	ifa_metric;		/* cost of going out this interface */
535	int (*ifa_claim_addr)		/* check if an addr goes to this if */
536		(struct ifaddr *, struct sockaddr *);
537	struct mtx ifa_mtx;
538};
539#define	IFA_ROUTE	RTF_UP		/* route installed */
540
541/* for compatibility with other BSDs */
542#define	ifa_list	ifa_link
543
544#define	IFA_LOCK_INIT(ifa)	\
545    mtx_init(&(ifa)->ifa_mtx, "ifaddr", NULL, MTX_DEF)
546#define	IFA_LOCK(ifa)		mtx_lock(&(ifa)->ifa_mtx)
547#define	IFA_UNLOCK(ifa)		mtx_unlock(&(ifa)->ifa_mtx)
548#define	IFA_DESTROY(ifa)	mtx_destroy(&(ifa)->ifa_mtx)
549
550/*
551 * The prefix structure contains information about one prefix
552 * of an interface.  They are maintained by the different address families,
553 * are allocated and attached when a prefix or an address is set,
554 * and are linked together so all prefixes for an interface can be located.
555 */
556struct ifprefix {
557	struct	sockaddr *ifpr_prefix;	/* prefix of interface */
558	struct	ifnet *ifpr_ifp;	/* back-pointer to interface */
559	TAILQ_ENTRY(ifprefix) ifpr_list; /* queue macro glue */
560	u_char	ifpr_plen;		/* prefix length in bits */
561	u_char	ifpr_type;		/* protocol dependent prefix type */
562};
563
564/*
565 * Multicast address structure.  This is analogous to the ifaddr
566 * structure except that it keeps track of multicast addresses.
567 * Also, the reference count here is a count of requests for this
568 * address, not a count of pointers to this structure.
569 */
570struct ifmultiaddr {
571	TAILQ_ENTRY(ifmultiaddr) ifma_link; /* queue macro glue */
572	struct	sockaddr *ifma_addr; 	/* address this membership is for */
573	struct	sockaddr *ifma_lladdr;	/* link-layer translation, if any */
574	struct	ifnet *ifma_ifp;	/* back-pointer to interface */
575	u_int	ifma_refcount;		/* reference count */
576	void	*ifma_protospec;	/* protocol-specific state, if any */
577};
578
579#ifdef _KERNEL
580#define	IFAFREE(ifa)					\
581	do {						\
582		IFA_LOCK(ifa);				\
583		KASSERT((ifa)->ifa_refcnt > 0,		\
584		    ("ifa %p !(ifa_refcnt > 0)", ifa));	\
585		if (--(ifa)->ifa_refcnt == 0) {		\
586			IFA_DESTROY(ifa);		\
587			free(ifa, M_IFADDR);		\
588		} else 					\
589			IFA_UNLOCK(ifa);		\
590	} while (0)
591
592#define IFAREF(ifa)					\
593	do {						\
594		IFA_LOCK(ifa);				\
595		++(ifa)->ifa_refcnt;			\
596		IFA_UNLOCK(ifa);			\
597	} while (0)
598
599extern	struct mtx ifnet_lock;
600#define	IFNET_LOCK_INIT() \
601    mtx_init(&ifnet_lock, "ifnet", NULL, MTX_DEF | MTX_RECURSE)
602#define	IFNET_WLOCK()		mtx_lock(&ifnet_lock)
603#define	IFNET_WUNLOCK()		mtx_unlock(&ifnet_lock)
604#define	IFNET_RLOCK()		IFNET_WLOCK()
605#define	IFNET_RUNLOCK()		IFNET_WUNLOCK()
606
607struct ifindex_entry {
608	struct	ifnet *ife_ifnet;
609	struct cdev *ife_dev;
610};
611
612#define ifnet_byindex(idx)	ifindex_table[(idx)].ife_ifnet
613/*
614 * Given the index, ifaddr_byindex() returns the one and only
615 * link-level ifaddr for the interface. You are not supposed to use
616 * it to traverse the list of addresses associated to the interface.
617 */
618#define ifaddr_byindex(idx)	ifnet_byindex(idx)->if_addr
619#define ifdev_byindex(idx)	ifindex_table[(idx)].ife_dev
620
621extern	struct ifnethead ifnet;
622extern	struct ifindex_entry *ifindex_table;
623extern	int ifqmaxlen;
624extern	struct ifnet *loif;	/* first loopback interface */
625extern	int if_index;
626
627int	if_addmulti(struct ifnet *, struct sockaddr *, struct ifmultiaddr **);
628int	if_allmulti(struct ifnet *, int);
629struct	ifnet* if_alloc(u_char);
630void	if_attach(struct ifnet *);
631int	if_delmulti(struct ifnet *, struct sockaddr *);
632void	if_detach(struct ifnet *);
633void	if_purgeaddrs(struct ifnet *);
634void	if_down(struct ifnet *);
635void	if_free(struct ifnet *);
636void	if_free_type(struct ifnet *, u_char);
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
653int	if_simloop(struct ifnet *ifp, struct mbuf *m, int af, int hlen);
654
655typedef	void *if_com_alloc_t(u_char type, struct ifnet *ifp);
656typedef	void if_com_free_t(void *com, u_char type);
657void	if_register_com_alloc(u_char type, if_com_alloc_t *a, if_com_free_t *f);
658void	if_deregister_com_alloc(u_char type);
659
660#define IF_LLADDR(ifp)							\
661    LLADDR((struct sockaddr_dl *)((ifp)->if_addr->ifa_addr))
662
663#ifdef DEVICE_POLLING
664enum poll_cmd {	POLL_ONLY, POLL_AND_CHECK_STATUS };
665
666typedef	void poll_handler_t(struct ifnet *ifp, enum poll_cmd cmd, int count);
667int    ether_poll_register(poll_handler_t *h, struct ifnet *ifp);
668int    ether_poll_deregister(struct ifnet *ifp);
669#endif /* DEVICE_POLLING */
670
671#endif /* _KERNEL */
672
673#endif /* !_NET_IF_VAR_H_ */
674