ifq.h revision 132152
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 132152 2004-07-14 13:31:41Z mlaier $
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;
71#endif
72
73#include <sys/queue.h>		/* get TAILQ macros */
74
75#ifdef _KERNEL
76#include <sys/mbuf.h>
77#include <sys/eventhandler.h>
78#endif /* _KERNEL */
79#include <sys/lock.h>		/* XXX */
80#include <sys/mutex.h>		/* XXX */
81#include <sys/event.h>		/* XXX */
82
83#define	IF_DUNIT_NONE	-1
84
85#if 1 /* ALTQ */
86#include <altq/if_altq.h>
87#endif
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	klist if_klist;		/* events attached to this if */
149	int	if_pcount;		/* number of promiscuous listeners */
150	struct	bpf_if *if_bpf;		/* packet filter structure */
151	u_short	if_index;		/* numeric abbreviation for this if  */
152	short	if_timer;		/* time 'til if_watchdog called */
153	u_short	if_nvlans;		/* number of active vlans */
154	int	if_flags;		/* up/down, broadcast, etc. */
155	int	if_capabilities;	/* interface capabilities */
156	int	if_capenable;		/* enabled features */
157	void	*if_linkmib;		/* link-type-specific MIB data */
158	size_t	if_linkmiblen;		/* length of above data */
159	struct	if_data if_data;
160	struct	ifmultihead if_multiaddrs; /* multicast addresses configured */
161	int	if_amcount;		/* number of all-multicast requests */
162/* procedure handles */
163	int	(*if_output)		/* output routine (enqueue) */
164		(struct ifnet *, struct mbuf *, struct sockaddr *,
165		     struct rtentry *);
166	void	(*if_input)		/* input routine (from h/w driver) */
167		(struct ifnet *, struct mbuf *);
168	void	(*if_start)		/* initiate output routine */
169		(struct ifnet *);
170	int	(*if_ioctl)		/* ioctl routine */
171		(struct ifnet *, u_long, caddr_t);
172	void	(*if_watchdog)		/* timer routine */
173		(struct ifnet *);
174	void	(*if_init)		/* Init routine */
175		(void *);
176	int	(*if_resolvemulti)	/* validate/resolve multicast */
177		(struct ifnet *, struct sockaddr **, struct sockaddr *);
178#if 1 /* ALTQ */
179	struct  ifaltq if_snd;		/* output queue (includes altq) */
180#else
181	struct	ifqueue if_snd;		/* output queue */
182#endif
183	const u_int8_t *if_broadcastaddr; /* linklevel broadcast bytestring */
184
185	struct	lltable *lltables;	/* list of L3-L2 resolution tables */
186
187	struct	label *if_label;	/* interface MAC label */
188
189	/* these are only used by IPv6 */
190	struct	ifprefixhead if_prefixhead; /* list of prefixes per if */
191	void	*if_afdata[AF_MAX];
192	int	if_afdata_initialized;
193	struct	mtx if_afdata_mtx;
194};
195
196typedef void if_init_f_t(void *);
197
198/*
199 * XXX These aliases are terribly dangerous because they could apply
200 * to anything.
201 */
202#define	if_mtu		if_data.ifi_mtu
203#define	if_type		if_data.ifi_type
204#define if_physical	if_data.ifi_physical
205#define	if_addrlen	if_data.ifi_addrlen
206#define	if_hdrlen	if_data.ifi_hdrlen
207#define	if_metric	if_data.ifi_metric
208#define	if_link_state	if_data.ifi_link_state
209#define	if_baudrate	if_data.ifi_baudrate
210#define	if_hwassist	if_data.ifi_hwassist
211#define	if_ipackets	if_data.ifi_ipackets
212#define	if_ierrors	if_data.ifi_ierrors
213#define	if_opackets	if_data.ifi_opackets
214#define	if_oerrors	if_data.ifi_oerrors
215#define	if_collisions	if_data.ifi_collisions
216#define	if_ibytes	if_data.ifi_ibytes
217#define	if_obytes	if_data.ifi_obytes
218#define	if_imcasts	if_data.ifi_imcasts
219#define	if_omcasts	if_data.ifi_omcasts
220#define	if_iqdrops	if_data.ifi_iqdrops
221#define	if_noproto	if_data.ifi_noproto
222#define	if_lastchange	if_data.ifi_lastchange
223#define if_recvquota	if_data.ifi_recvquota
224#define	if_xmitquota	if_data.ifi_xmitquota
225#define if_rawoutput(if, m, sa) if_output(if, m, sa, (struct rtentry *)0)
226
227/* for compatibility with other BSDs */
228#define	if_addrlist	if_addrhead
229#define	if_list		if_link
230
231/*
232 * Output queues (ifp->if_snd) and slow device input queues (*ifp->if_slowq)
233 * are queues of messages stored on ifqueue structures
234 * (defined above).  Entries are added to and deleted from these structures
235 * by these macros, which should be called with ipl raised to splimp().
236 */
237#define IF_LOCK(ifq)		mtx_lock(&(ifq)->ifq_mtx)
238#define IF_UNLOCK(ifq)		mtx_unlock(&(ifq)->ifq_mtx)
239#define	IF_LOCK_ASSERT(ifq)	mtx_assert(&(ifq)->ifq_mtx, MA_OWNED)
240#define	_IF_QFULL(ifq)		((ifq)->ifq_len >= (ifq)->ifq_maxlen)
241#define	_IF_DROP(ifq)		((ifq)->ifq_drops++)
242#define	_IF_QLEN(ifq)		((ifq)->ifq_len)
243
244#define	_IF_ENQUEUE(ifq, m) do { 				\
245	(m)->m_nextpkt = NULL;					\
246	if ((ifq)->ifq_tail == NULL) 				\
247		(ifq)->ifq_head = m; 				\
248	else 							\
249		(ifq)->ifq_tail->m_nextpkt = m; 		\
250	(ifq)->ifq_tail = m; 					\
251	(ifq)->ifq_len++; 					\
252} while (0)
253
254#define IF_ENQUEUE(ifq, m) do {					\
255	IF_LOCK(ifq); 						\
256	_IF_ENQUEUE(ifq, m); 					\
257	IF_UNLOCK(ifq); 					\
258} while (0)
259
260#define	_IF_PREPEND(ifq, m) do {				\
261	(m)->m_nextpkt = (ifq)->ifq_head; 			\
262	if ((ifq)->ifq_tail == NULL) 				\
263		(ifq)->ifq_tail = (m); 				\
264	(ifq)->ifq_head = (m); 					\
265	(ifq)->ifq_len++; 					\
266} while (0)
267
268#define IF_PREPEND(ifq, m) do {		 			\
269	IF_LOCK(ifq); 						\
270	_IF_PREPEND(ifq, m); 					\
271	IF_UNLOCK(ifq); 					\
272} while (0)
273
274#define	_IF_DEQUEUE(ifq, m) do { 				\
275	(m) = (ifq)->ifq_head; 					\
276	if (m) { 						\
277		if (((ifq)->ifq_head = (m)->m_nextpkt) == 0) 	\
278			(ifq)->ifq_tail = NULL; 		\
279		(m)->m_nextpkt = NULL; 				\
280		(ifq)->ifq_len--; 				\
281	} 							\
282} while (0)
283
284#define IF_DEQUEUE(ifq, m) do { 				\
285	IF_LOCK(ifq); 						\
286	_IF_DEQUEUE(ifq, m); 					\
287	IF_UNLOCK(ifq); 					\
288} while (0)
289
290#define	_IF_POLL(ifq, m)	((m) = (ifq)->ifq_head)
291#define	IF_POLL(ifq, m)		_IF_POLL(ifq, m)
292
293#define _IF_DRAIN(ifq) do { 					\
294	struct mbuf *m; 					\
295	for (;;) { 						\
296		_IF_DEQUEUE(ifq, m); 				\
297		if (m == NULL) 					\
298			break; 					\
299		m_freem(m); 					\
300	} 							\
301} while (0)
302
303#define IF_DRAIN(ifq) do {					\
304	IF_LOCK(ifq);						\
305	_IF_DRAIN(ifq);						\
306	IF_UNLOCK(ifq);						\
307} while(0)
308
309#ifdef _KERNEL
310/* interface address change event */
311typedef void (*ifaddr_event_handler_t)(void *, struct ifnet *);
312EVENTHANDLER_DECLARE(ifaddr_event, ifaddr_event_handler_t);
313/* new interface arrival event */
314typedef void (*ifnet_arrival_event_handler_t)(void *, struct ifnet *);
315EVENTHANDLER_DECLARE(ifnet_arrival_event, ifnet_arrival_event_handler_t);
316/* interface departure event */
317typedef void (*ifnet_departure_event_handler_t)(void *, struct ifnet *);
318EVENTHANDLER_DECLARE(ifnet_departure_event, ifnet_departure_event_handler_t);
319
320#define	IF_AFDATA_LOCK_INIT(ifp)	\
321    mtx_init(&(ifp)->if_afdata_mtx, "if_afdata", NULL, MTX_DEF)
322#define	IF_AFDATA_LOCK(ifp)	mtx_lock(&(ifp)->if_afdata_mtx)
323#define	IF_AFDATA_TRYLOCK(ifp)	mtx_trylock(&(ifp)->if_afdata_mtx)
324#define	IF_AFDATA_UNLOCK(ifp)	mtx_unlock(&(ifp)->if_afdata_mtx)
325#define	IF_AFDATA_DESTROY(ifp)	mtx_destroy(&(ifp)->if_afdata_mtx)
326
327#define	IF_HANDOFF(ifq, m, ifp)			\
328	if_handoff((struct ifqueue *)ifq, m, ifp, 0)
329#define	IF_HANDOFF_ADJ(ifq, m, ifp, adj)	\
330	if_handoff((struct ifqueue *)ifq, m, ifp, adj)
331
332static __inline int
333if_handoff(struct ifqueue *ifq, struct mbuf *m, struct ifnet *ifp, int adjust)
334{
335	int active = 0;
336
337	IF_LOCK(ifq);
338	if (_IF_QFULL(ifq)) {
339		_IF_DROP(ifq);
340		IF_UNLOCK(ifq);
341		m_freem(m);
342		return (0);
343	}
344	if (ifp != NULL) {
345		ifp->if_obytes += m->m_pkthdr.len + adjust;
346		if (m->m_flags & (M_BCAST|M_MCAST))
347			ifp->if_omcasts++;
348		active = ifp->if_flags & IFF_OACTIVE;
349	}
350	_IF_ENQUEUE(ifq, m);
351	IF_UNLOCK(ifq);
352	if (ifp != NULL && !active)
353		(*ifp->if_start)(ifp);
354	return (1);
355}
356#if 1 /* ALTQ */
357#define	IFQ_ENQUEUE(ifq, m, err)					\
358do {									\
359	IF_LOCK(ifq);							\
360	if (ALTQ_IS_ENABLED(ifq))					\
361		ALTQ_ENQUEUE(ifq, m, NULL, err);			\
362	else {								\
363		if (_IF_QFULL(ifq)) {					\
364			m_freem(m);					\
365			(err) = ENOBUFS;				\
366		} else {						\
367			_IF_ENQUEUE(ifq, m);				\
368			(err) = 0;					\
369		}							\
370	}								\
371	if (err)							\
372		(ifq)->ifq_drops++;					\
373	IF_UNLOCK(ifq);							\
374} while (0)
375
376#define	IFQ_DEQUEUE_NOLOCK(ifq, m)					\
377do {									\
378	if (TBR_IS_ENABLED(ifq))					\
379		(m) = tbr_dequeue_ptr(ifq, ALTDQ_REMOVE);		\
380	else if (ALTQ_IS_ENABLED(ifq))					\
381		ALTQ_DEQUEUE(ifq, m);					\
382	else								\
383		_IF_DEQUEUE(ifq, m);					\
384} while (0)
385
386#define	IFQ_DEQUEUE(ifq, m)						\
387do {									\
388	IF_LOCK(ifq);							\
389	IFQ_DEQUEUE_NOLOCK(ifq, m);					\
390	IF_UNLOCK(ifq);							\
391} while (0)
392
393#define	IFQ_POLL_NOLOCK(ifq, m)						\
394do {									\
395	if (TBR_IS_ENABLED(ifq))					\
396		(m) = tbr_dequeue_ptr(ifq, ALTDQ_POLL);			\
397	else if (ALTQ_IS_ENABLED(ifq))					\
398		ALTQ_POLL(ifq, m);					\
399	else								\
400		_IF_POLL(ifq, m);					\
401} while (0)
402
403#define	IFQ_POLL(ifq, m)						\
404do {									\
405	IF_LOCK(ifq);							\
406	IFQ_POLL_NOLOCK(ifq, m);					\
407	IF_UNLOCK(ifq);							\
408} while (0)
409
410#define	IFQ_PURGE_NOLOCK(ifq)						\
411do {									\
412	if (ALTQ_IS_ENABLED(ifq)) {					\
413		ALTQ_PURGE(ifq);					\
414	} else								\
415		_IF_DRAIN(ifq);						\
416} while (0)
417
418#define	IFQ_PURGE(ifq)							\
419do {									\
420	IF_LOCK(ifq);							\
421	IFQ_PURGE_NOLOCK(ifq);						\
422	IF_UNLOCK(ifq);							\
423} while (0)
424
425#define	IFQ_SET_READY(ifq)						\
426	do { ((ifq)->altq_flags |= ALTQF_READY); } while (0)
427
428#else /* !ALTQ */
429#define	IFQ_ENQUEUE(ifq, m, err)					\
430do {									\
431	IF_LOCK(ifq);							\
432	if (_IF_QFULL(ifq)) {						\
433		m_freem(m);						\
434		(err) = ENOBUFS;					\
435	} else {							\
436		_IF_ENQUEUE(ifq, m);					\
437		(err) = 0;						\
438	}								\
439	if (err)							\
440		(ifq)->ifq_drops++;					\
441	IF_UNLOCK(ifq);							\
442} while (0)
443
444#define	IFQ_DEQUEUE_NOLOCK(ifq, m)	_IF_DEQUEUE(ifq, m)
445#define	IFQ_DEQUEUE(ifq, m)		IF_DEQUEUE(ifq, m)
446#define	IFQ_POLL_NOLOCK(ifq, m)		_IF_POLL(ifq, m)
447#define	IFQ_POLL(ifq, m)		IF_POLL(ifq, m)
448#define	IFQ_PURGE_NOLOCK(ifq)		_IF_DRAIN(ifq)
449#define	IFQ_PURGE(ifq)			IF_DRAIN(ifq)
450
451#define	IFQ_SET_READY(ifq)		/* nothing */
452
453#endif /* !ALTQ */
454
455#define	IFQ_LOCK(ifq)			IF_LOCK(ifq)
456#define	IFQ_UNLOCK(ifq)			IF_UNLOCK(ifq)
457#define	IFQ_LOCK_ASSERT(ifq)		IF_LOCK_ASSERT(ifq)
458#define	IFQ_IS_EMPTY(ifq)		((ifq)->ifq_len == 0)
459#define	IFQ_INC_LEN(ifq)		((ifq)->ifq_len++)
460#define	IFQ_DEC_LEN(ifq)		(--(ifq)->ifq_len)
461#define	IFQ_INC_DROPS(ifq)		((ifq)->ifq_drops++)
462#define	IFQ_SET_MAXLEN(ifq, len)	((ifq)->ifq_maxlen = (len))
463
464#define	IFQ_HANDOFF_ADJ(ifp, m, adj, err)				\
465do {									\
466	int len;							\
467	short mflags;							\
468									\
469	len = (m)->m_pkthdr.len;					\
470	mflags = (m)->m_flags;						\
471	IFQ_ENQUEUE(&(ifp)->if_snd, m, err);				\
472	if ((err) == 0) {						\
473		(ifp)->if_obytes += len + (adj);			\
474		if (mflags & M_MCAST)					\
475			(ifp)->if_omcasts++;				\
476		if (((ifp)->if_flags & IFF_OACTIVE) == 0)		\
477			(*(ifp)->if_start)(ifp);			\
478	}								\
479} while (0)
480
481#define	IFQ_HANDOFF(ifp, m, err)					\
482	IFQ_HANDOFF_ADJ(ifp, m, 0, err)
483
484#define	IFQ_DRV_DEQUEUE(ifq, m)						\
485do {									\
486	(m) = (ifq)->ifq_drv_head;					\
487	if (m) {							\
488		if (((ifq)->ifq_drv_head = (m)->m_nextpkt) == NULL)	\
489			(ifq)->ifq_drv_tail = NULL;			\
490		(m)->m_nextpkt = NULL;					\
491		(ifq)->ifq_drv_len--;					\
492	} else {							\
493		IFQ_LOCK(ifq);						\
494		IFQ_DEQUEUE_NOLOCK(ifq, m);				\
495		while ((ifq)->ifq_drv_len < (ifq)->ifq_drv_maxlen) {	\
496			struct mbuf *m0;				\
497			IFQ_DEQUEUE_NOLOCK(ifq, m0);			\
498			if (m0 == NULL)					\
499				break;					\
500			m0->m_nextpkt = NULL;				\
501			if ((ifq)->ifq_drv_tail == NULL)		\
502				(ifq)->ifq_drv_head = m0;		\
503			else						\
504				(ifq)->ifq_drv_tail->m_nextpkt = m0;	\
505			(ifq)->ifq_drv_tail = m0;			\
506			(ifq)->ifq_drv_len++;				\
507		}							\
508		IFQ_UNLOCK(ifq);					\
509	}								\
510} while (0)
511
512#define	IFQ_DRV_PREPEND(ifq, m)						\
513do {									\
514	(m)->m_nextpkt = (ifq)->ifq_drv_head;				\
515	if ((ifq)->ifq_drv_tail == NULL)				\
516		(ifq)->ifq_drv_tail = (m);				\
517	(ifq)->ifq_drv_head = (m);					\
518	(ifq)->ifq_drv_len++;						\
519} while (0)
520
521#define	IFQ_DRV_IS_EMPTY(ifq)						\
522	(((ifq)->ifq_drv_len == 0) && ((ifq)->ifq_len == 0))
523
524#define	IFQ_DRV_PURGE(ifq)						\
525do {									\
526	struct mbuf *m, *n = (ifq)->ifq_drv_head;			\
527	while((m = n) != NULL) {					\
528		n = m->m_nextpkt;					\
529		m_freem(m);						\
530	}								\
531	(ifq)->ifq_drv_head = (ifq)->ifq_drv_tail = NULL;		\
532	(ifq)->ifq_drv_len = 0;						\
533	IFQ_PURGE(ifq);							\
534} while (0)
535
536/*
537 * 72 was chosen below because it is the size of a TCP/IP
538 * header (40) + the minimum mss (32).
539 */
540#define	IF_MINMTU	72
541#define	IF_MAXMTU	65535
542
543#endif /* _KERNEL */
544
545/*
546 * The ifaddr structure contains information about one address
547 * of an interface.  They are maintained by the different address families,
548 * are allocated and attached when an address is set, and are linked
549 * together so all addresses for an interface can be located.
550 *
551 * NOTE: a 'struct ifaddr' is always at the beginning of a larger
552 * chunk of malloc'ed memory, where we store the three addresses
553 * (ifa_addr, ifa_dstaddr and ifa_netmask) referenced here.
554 */
555struct ifaddr {
556	struct	sockaddr *ifa_addr;	/* address of interface */
557	struct	sockaddr *ifa_dstaddr;	/* other end of p-to-p link */
558#define	ifa_broadaddr	ifa_dstaddr	/* broadcast address interface */
559	struct	sockaddr *ifa_netmask;	/* used to determine subnet */
560	struct	if_data if_data;	/* not all members are meaningful */
561	struct	ifnet *ifa_ifp;		/* back-pointer to interface */
562	TAILQ_ENTRY(ifaddr) ifa_link;	/* queue macro glue */
563	void	(*ifa_rtrequest)	/* check or clean routes (+ or -)'d */
564		(int, struct rtentry *, struct rt_addrinfo *);
565	u_short	ifa_flags;		/* mostly rt_flags for cloning */
566	u_int	ifa_refcnt;		/* references to this structure */
567	int	ifa_metric;		/* cost of going out this interface */
568	int (*ifa_claim_addr)		/* check if an addr goes to this if */
569		(struct ifaddr *, struct sockaddr *);
570	struct mtx ifa_mtx;
571};
572#define	IFA_ROUTE	RTF_UP		/* route installed */
573
574/* for compatibility with other BSDs */
575#define	ifa_list	ifa_link
576
577#define	IFA_LOCK_INIT(ifa)	\
578    mtx_init(&(ifa)->ifa_mtx, "ifaddr", NULL, MTX_DEF)
579#define	IFA_LOCK(ifa)		mtx_lock(&(ifa)->ifa_mtx)
580#define	IFA_UNLOCK(ifa)		mtx_unlock(&(ifa)->ifa_mtx)
581#define	IFA_DESTROY(ifa)	mtx_destroy(&(ifa)->ifa_mtx)
582
583/*
584 * The prefix structure contains information about one prefix
585 * of an interface.  They are maintained by the different address families,
586 * are allocated and attached when a prefix or an address is set,
587 * and are linked together so all prefixes for an interface can be located.
588 */
589struct ifprefix {
590	struct	sockaddr *ifpr_prefix;	/* prefix of interface */
591	struct	ifnet *ifpr_ifp;	/* back-pointer to interface */
592	TAILQ_ENTRY(ifprefix) ifpr_list; /* queue macro glue */
593	u_char	ifpr_plen;		/* prefix length in bits */
594	u_char	ifpr_type;		/* protocol dependent prefix type */
595};
596
597/*
598 * Multicast address structure.  This is analogous to the ifaddr
599 * structure except that it keeps track of multicast addresses.
600 * Also, the reference count here is a count of requests for this
601 * address, not a count of pointers to this structure.
602 */
603struct ifmultiaddr {
604	TAILQ_ENTRY(ifmultiaddr) ifma_link; /* queue macro glue */
605	struct	sockaddr *ifma_addr; 	/* address this membership is for */
606	struct	sockaddr *ifma_lladdr;	/* link-layer translation, if any */
607	struct	ifnet *ifma_ifp;	/* back-pointer to interface */
608	u_int	ifma_refcount;		/* reference count */
609	void	*ifma_protospec;	/* protocol-specific state, if any */
610};
611
612#ifdef _KERNEL
613#define	IFAFREE(ifa)					\
614	do {						\
615		IFA_LOCK(ifa);				\
616		KASSERT((ifa)->ifa_refcnt > 0,		\
617		    ("ifa %p !(ifa_refcnt > 0)", ifa));	\
618		if (--(ifa)->ifa_refcnt == 0) {		\
619			IFA_DESTROY(ifa);		\
620			free(ifa, M_IFADDR);		\
621		} else 					\
622			IFA_UNLOCK(ifa);		\
623	} while (0)
624
625#define IFAREF(ifa)					\
626	do {						\
627		IFA_LOCK(ifa);				\
628		++(ifa)->ifa_refcnt;			\
629		IFA_UNLOCK(ifa);			\
630	} while (0)
631
632extern	struct mtx ifnet_lock;
633#define	IFNET_LOCK_INIT() \
634    mtx_init(&ifnet_lock, "ifnet", NULL, MTX_DEF | MTX_RECURSE)
635#define	IFNET_WLOCK()		mtx_lock(&ifnet_lock)
636#define	IFNET_WUNLOCK()		mtx_unlock(&ifnet_lock)
637#define	IFNET_RLOCK()		IFNET_WLOCK()
638#define	IFNET_RUNLOCK()		IFNET_WUNLOCK()
639
640struct ifindex_entry {
641	struct	ifnet *ife_ifnet;
642	struct	ifaddr *ife_ifnet_addr;
643	struct cdev *ife_dev;
644};
645
646#define ifnet_byindex(idx)	ifindex_table[(idx)].ife_ifnet
647/*
648 * Given the index, ifaddr_byindex() returns the one and only
649 * link-level ifaddr for the interface. You are not supposed to use
650 * it to traverse the list of addresses associated to the interface.
651 */
652#define ifaddr_byindex(idx)	ifindex_table[(idx)].ife_ifnet_addr
653#define ifdev_byindex(idx)	ifindex_table[(idx)].ife_dev
654
655extern	struct ifnethead ifnet;
656extern	struct ifindex_entry *ifindex_table;
657extern	int ifqmaxlen;
658extern	struct ifnet *loif;	/* first loopback interface */
659extern	int if_index;
660
661int	if_addmulti(struct ifnet *, struct sockaddr *, struct ifmultiaddr **);
662int	if_allmulti(struct ifnet *, int);
663void	if_attach(struct ifnet *);
664int	if_delmulti(struct ifnet *, struct sockaddr *);
665void	if_detach(struct ifnet *);
666void	if_down(struct ifnet *);
667void	if_initname(struct ifnet *, const char *, int);
668int	if_printf(struct ifnet *, const char *, ...) __printflike(2, 3);
669int	if_setlladdr(struct ifnet *, const u_char *, int);
670void	if_up(struct ifnet *);
671/*void	ifinit(void);*/ /* declared in systm.h for main() */
672int	ifioctl(struct socket *, u_long, caddr_t, struct thread *);
673int	ifpromisc(struct ifnet *, int);
674struct	ifnet *ifunit(const char *);
675
676struct	ifaddr *ifa_ifwithaddr(struct sockaddr *);
677struct	ifaddr *ifa_ifwithdstaddr(struct sockaddr *);
678struct	ifaddr *ifa_ifwithnet(struct sockaddr *);
679struct	ifaddr *ifa_ifwithroute(int, struct sockaddr *, struct sockaddr *);
680struct	ifaddr *ifaof_ifpforaddr(struct sockaddr *, struct ifnet *);
681
682struct	ifmultiaddr *ifmaof_ifpforaddr(struct sockaddr *, struct ifnet *);
683int	if_simloop(struct ifnet *ifp, struct mbuf *m, int af, int hlen);
684
685#define IF_LLADDR(ifp)							\
686    LLADDR((struct sockaddr_dl *) ifaddr_byindex((ifp)->if_index)->ifa_addr)
687
688#ifdef DEVICE_POLLING
689enum poll_cmd {	POLL_ONLY, POLL_AND_CHECK_STATUS, POLL_DEREGISTER };
690
691typedef	void poll_handler_t(struct ifnet *ifp, enum poll_cmd cmd, int count);
692int    ether_poll_register(poll_handler_t *h, struct ifnet *ifp);
693int    ether_poll_deregister(struct ifnet *ifp);
694#endif /* DEVICE_POLLING */
695
696#endif /* _KERNEL */
697
698#endif /* !_NET_IF_VAR_H_ */
699