xref: /freebsd/sys/net/if_var.h (revision 54ebdd631db8c0bba2baab0155f603a8b5cf014a)
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  * $FreeBSD$
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  */
65 struct	mbuf;
66 struct	thread;
67 struct	rtentry;
68 struct	rt_addrinfo;
69 struct	socket;
70 struct	ether_header;
71 struct	carp_if;
72 struct  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 
90 TAILQ_HEAD(ifnethead, ifnet);	/* we use TAILQs so that the order of */
91 TAILQ_HEAD(ifaddrhead, ifaddr);	/* instantiation is preserved in the list */
92 TAILQ_HEAD(ifprefixhead, ifprefix);
93 TAILQ_HEAD(ifmultihead, ifmultiaddr);
94 TAILQ_HEAD(ifgrouphead, ifg_group);
95 
96 /*
97  * Structure defining a queue for a network interface.
98  */
99 struct	ifqueue {
100 	struct	mbuf *ifq_head;
101 	struct	mbuf *ifq_tail;
102 	int	ifq_len;
103 	int	ifq_maxlen;
104 	int	ifq_drops;
105 	struct	mtx ifq_mtx;
106 };
107 
108 /*
109  * Structure defining a network interface.
110  *
111  * (Would like to call this struct ``if'', but C isn't PL/1.)
112  */
113 
114 struct ifnet {
115 	void	*if_softc;		/* pointer to driver state */
116 	void	*if_l2com;		/* pointer to protocol bits */
117 	TAILQ_ENTRY(ifnet) if_link; 	/* all struct ifnets are chained */
118 	char	if_xname[IFNAMSIZ];	/* external name (name + unit) */
119 	const char *if_dname;		/* driver name */
120 	int	if_dunit;		/* unit or IF_DUNIT_NONE */
121 	struct	ifaddrhead if_addrhead;	/* linked list of addresses per if */
122 		/*
123 		 * if_addrhead is the list of all addresses associated to
124 		 * an interface.
125 		 * Some code in the kernel assumes that first element
126 		 * of the list has type AF_LINK, and contains sockaddr_dl
127 		 * addresses which store the link-level address and the name
128 		 * of the interface.
129 		 * However, access to the AF_LINK address through this
130 		 * field is deprecated. Use if_addr or ifaddr_byindex() instead.
131 		 */
132 	struct	knlist if_klist;	/* events attached to this if */
133 	int	if_pcount;		/* number of promiscuous listeners */
134 	struct	carp_if *if_carp;	/* carp interface structure */
135 	struct	bpf_if *if_bpf;		/* packet filter structure */
136 	u_short	if_index;		/* numeric abbreviation for this if  */
137 	short	if_timer;		/* time 'til if_watchdog called */
138 	struct  ifvlantrunk *if_vlantrunk; /* pointer to 802.1q data */
139 	int	if_flags;		/* up/down, broadcast, etc. */
140 	int	if_capabilities;	/* interface features & capabilities */
141 	int	if_capenable;		/* enabled features & capabilities */
142 	void	*if_linkmib;		/* link-type-specific MIB data */
143 	size_t	if_linkmiblen;		/* length of above data */
144 	struct	if_data if_data;
145 	struct	ifmultihead if_multiaddrs; /* multicast addresses configured */
146 	int	if_amcount;		/* number of all-multicast requests */
147 /* procedure handles */
148 	int	(*if_output)		/* output routine (enqueue) */
149 		(struct ifnet *, struct mbuf *, struct sockaddr *,
150 		     struct rtentry *);
151 	void	(*if_input)		/* input routine (from h/w driver) */
152 		(struct ifnet *, struct mbuf *);
153 	void	(*if_start)		/* initiate output routine */
154 		(struct ifnet *);
155 	int	(*if_ioctl)		/* ioctl routine */
156 		(struct ifnet *, u_long, caddr_t);
157 	void	(*if_watchdog)		/* timer routine */
158 		(struct ifnet *);
159 	void	(*if_init)		/* Init routine */
160 		(void *);
161 	int	(*if_resolvemulti)	/* validate/resolve multicast */
162 		(struct ifnet *, struct sockaddr **, struct sockaddr *);
163 	struct	ifaddr	*if_addr;	/* pointer to link-level address */
164 	void	*if_llsoftc;		/* link layer softc */
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 	TAILQ_HEAD(, ifg_list) if_groups; /* linked list of groups per if */
186 					/* protected by if_addr_mtx */
187 	void	*if_pf_kif;
188 	void	*if_lagg;		/* lagg glue */
189 	void	*if_pspare[8];		/* multiq/TOE 3; vimage 3; general use 4 */
190 	void	(*if_qflush)	/* flush any queues */
191 		(struct ifnet *);
192 	int	(*if_transmit)	/* initiate output routine */
193 		(struct ifnet *, struct mbuf *);
194 	int	if_ispare[2];		/* general use 2 */
195 };
196 
197 typedef void if_init_f_t(void *);
198 
199 /*
200  * XXX These aliases are terribly dangerous because they could apply
201  * to anything.
202  */
203 #define	if_mtu		if_data.ifi_mtu
204 #define	if_type		if_data.ifi_type
205 #define if_physical	if_data.ifi_physical
206 #define	if_addrlen	if_data.ifi_addrlen
207 #define	if_hdrlen	if_data.ifi_hdrlen
208 #define	if_metric	if_data.ifi_metric
209 #define	if_link_state	if_data.ifi_link_state
210 #define	if_baudrate	if_data.ifi_baudrate
211 #define	if_hwassist	if_data.ifi_hwassist
212 #define	if_ipackets	if_data.ifi_ipackets
213 #define	if_ierrors	if_data.ifi_ierrors
214 #define	if_opackets	if_data.ifi_opackets
215 #define	if_oerrors	if_data.ifi_oerrors
216 #define	if_collisions	if_data.ifi_collisions
217 #define	if_ibytes	if_data.ifi_ibytes
218 #define	if_obytes	if_data.ifi_obytes
219 #define	if_imcasts	if_data.ifi_imcasts
220 #define	if_omcasts	if_data.ifi_omcasts
221 #define	if_iqdrops	if_data.ifi_iqdrops
222 #define	if_noproto	if_data.ifi_noproto
223 #define	if_lastchange	if_data.ifi_lastchange
224 #define if_rawoutput(if, m, sa) if_output(if, m, sa, (struct rtentry *)NULL)
225 
226 /* for compatibility with other BSDs */
227 #define	if_addrlist	if_addrhead
228 #define	if_list		if_link
229 #define	if_name(ifp)	((ifp)->if_xname)
230 
231 /*
232  * Locks for address lists on the network interface.
233  */
234 #define	IF_ADDR_LOCK_INIT(if)	mtx_init(&(if)->if_addr_mtx,		\
235 				    "if_addr_mtx", NULL, MTX_DEF)
236 #define	IF_ADDR_LOCK_DESTROY(if)	mtx_destroy(&(if)->if_addr_mtx)
237 #define	IF_ADDR_LOCK(if)	mtx_lock(&(if)->if_addr_mtx)
238 #define	IF_ADDR_UNLOCK(if)	mtx_unlock(&(if)->if_addr_mtx)
239 #define	IF_ADDR_LOCK_ASSERT(if)	mtx_assert(&(if)->if_addr_mtx, MA_OWNED)
240 
241 /*
242  * Output queues (ifp->if_snd) and slow device input queues (*ifp->if_slowq)
243  * are queues of messages stored on ifqueue structures
244  * (defined above).  Entries are added to and deleted from these structures
245  * by these macros, which should be called with ipl raised to splimp().
246  */
247 #define IF_LOCK(ifq)		mtx_lock(&(ifq)->ifq_mtx)
248 #define IF_UNLOCK(ifq)		mtx_unlock(&(ifq)->ifq_mtx)
249 #define	IF_LOCK_ASSERT(ifq)	mtx_assert(&(ifq)->ifq_mtx, MA_OWNED)
250 #define	_IF_QFULL(ifq)		((ifq)->ifq_len >= (ifq)->ifq_maxlen)
251 #define	_IF_DROP(ifq)		((ifq)->ifq_drops++)
252 #define	_IF_QLEN(ifq)		((ifq)->ifq_len)
253 
254 #define	_IF_ENQUEUE(ifq, m) do { 				\
255 	(m)->m_nextpkt = NULL;					\
256 	if ((ifq)->ifq_tail == NULL) 				\
257 		(ifq)->ifq_head = m; 				\
258 	else 							\
259 		(ifq)->ifq_tail->m_nextpkt = m; 		\
260 	(ifq)->ifq_tail = m; 					\
261 	(ifq)->ifq_len++; 					\
262 } while (0)
263 
264 #define IF_ENQUEUE(ifq, m) do {					\
265 	IF_LOCK(ifq); 						\
266 	_IF_ENQUEUE(ifq, m); 					\
267 	IF_UNLOCK(ifq); 					\
268 } while (0)
269 
270 #define	_IF_PREPEND(ifq, m) do {				\
271 	(m)->m_nextpkt = (ifq)->ifq_head; 			\
272 	if ((ifq)->ifq_tail == NULL) 				\
273 		(ifq)->ifq_tail = (m); 				\
274 	(ifq)->ifq_head = (m); 					\
275 	(ifq)->ifq_len++; 					\
276 } while (0)
277 
278 #define IF_PREPEND(ifq, m) do {		 			\
279 	IF_LOCK(ifq); 						\
280 	_IF_PREPEND(ifq, m); 					\
281 	IF_UNLOCK(ifq); 					\
282 } while (0)
283 
284 #define	_IF_DEQUEUE(ifq, m) do { 				\
285 	(m) = (ifq)->ifq_head; 					\
286 	if (m) { 						\
287 		if (((ifq)->ifq_head = (m)->m_nextpkt) == NULL)	\
288 			(ifq)->ifq_tail = NULL; 		\
289 		(m)->m_nextpkt = NULL; 				\
290 		(ifq)->ifq_len--; 				\
291 	} 							\
292 } while (0)
293 
294 #define IF_DEQUEUE(ifq, m) do { 				\
295 	IF_LOCK(ifq); 						\
296 	_IF_DEQUEUE(ifq, m); 					\
297 	IF_UNLOCK(ifq); 					\
298 } while (0)
299 
300 #define	_IF_POLL(ifq, m)	((m) = (ifq)->ifq_head)
301 #define	IF_POLL(ifq, m)		_IF_POLL(ifq, m)
302 
303 #define _IF_DRAIN(ifq) do { 					\
304 	struct mbuf *m; 					\
305 	for (;;) { 						\
306 		_IF_DEQUEUE(ifq, m); 				\
307 		if (m == NULL) 					\
308 			break; 					\
309 		m_freem(m); 					\
310 	} 							\
311 } while (0)
312 
313 #define IF_DRAIN(ifq) do {					\
314 	IF_LOCK(ifq);						\
315 	_IF_DRAIN(ifq);						\
316 	IF_UNLOCK(ifq);						\
317 } while(0)
318 
319 #ifdef _KERNEL
320 /* interface address change event */
321 typedef void (*ifaddr_event_handler_t)(void *, struct ifnet *);
322 EVENTHANDLER_DECLARE(ifaddr_event, ifaddr_event_handler_t);
323 /* new interface arrival event */
324 typedef void (*ifnet_arrival_event_handler_t)(void *, struct ifnet *);
325 EVENTHANDLER_DECLARE(ifnet_arrival_event, ifnet_arrival_event_handler_t);
326 /* interface departure event */
327 typedef void (*ifnet_departure_event_handler_t)(void *, struct ifnet *);
328 EVENTHANDLER_DECLARE(ifnet_departure_event, ifnet_departure_event_handler_t);
329 
330 /*
331  * interface groups
332  */
333 struct ifg_group {
334 	char				 ifg_group[IFNAMSIZ];
335 	u_int				 ifg_refcnt;
336 	void				*ifg_pf_kif;
337 	TAILQ_HEAD(, ifg_member)	 ifg_members;
338 	TAILQ_ENTRY(ifg_group)		 ifg_next;
339 };
340 
341 struct ifg_member {
342 	TAILQ_ENTRY(ifg_member)	 ifgm_next;
343 	struct ifnet		*ifgm_ifp;
344 };
345 
346 struct ifg_list {
347 	struct ifg_group	*ifgl_group;
348 	TAILQ_ENTRY(ifg_list)	 ifgl_next;
349 };
350 
351 /* group attach event */
352 typedef void (*group_attach_event_handler_t)(void *, struct ifg_group *);
353 EVENTHANDLER_DECLARE(group_attach_event, group_attach_event_handler_t);
354 /* group detach event */
355 typedef void (*group_detach_event_handler_t)(void *, struct ifg_group *);
356 EVENTHANDLER_DECLARE(group_detach_event, group_detach_event_handler_t);
357 /* group change event */
358 typedef void (*group_change_event_handler_t)(void *, const char *);
359 EVENTHANDLER_DECLARE(group_change_event, group_change_event_handler_t);
360 
361 #define	IF_AFDATA_LOCK_INIT(ifp)	\
362     mtx_init(&(ifp)->if_afdata_mtx, "if_afdata", NULL, MTX_DEF)
363 #define	IF_AFDATA_LOCK(ifp)	mtx_lock(&(ifp)->if_afdata_mtx)
364 #define	IF_AFDATA_TRYLOCK(ifp)	mtx_trylock(&(ifp)->if_afdata_mtx)
365 #define	IF_AFDATA_UNLOCK(ifp)	mtx_unlock(&(ifp)->if_afdata_mtx)
366 #define	IF_AFDATA_DESTROY(ifp)	mtx_destroy(&(ifp)->if_afdata_mtx)
367 
368 #define	IFF_LOCKGIANT(ifp) do {						\
369 	if ((ifp)->if_flags & IFF_NEEDSGIANT)				\
370 		mtx_lock(&Giant);					\
371 } while (0)
372 
373 #define	IFF_UNLOCKGIANT(ifp) do {					\
374 	if ((ifp)->if_flags & IFF_NEEDSGIANT)				\
375 		mtx_unlock(&Giant);					\
376 } while (0)
377 
378 int	if_handoff(struct ifqueue *ifq, struct mbuf *m, struct ifnet *ifp,
379 	    int adjust);
380 #define	IF_HANDOFF(ifq, m, ifp)			\
381 	if_handoff((struct ifqueue *)ifq, m, ifp, 0)
382 #define	IF_HANDOFF_ADJ(ifq, m, ifp, adj)	\
383 	if_handoff((struct ifqueue *)ifq, m, ifp, adj)
384 
385 void	if_start(struct ifnet *);
386 
387 #define	IFQ_ENQUEUE(ifq, m, err)					\
388 do {									\
389 	IF_LOCK(ifq);							\
390 	if (ALTQ_IS_ENABLED(ifq))					\
391 		ALTQ_ENQUEUE(ifq, m, NULL, err);			\
392 	else {								\
393 		if (_IF_QFULL(ifq)) {					\
394 			m_freem(m);					\
395 			(err) = ENOBUFS;				\
396 		} else {						\
397 			_IF_ENQUEUE(ifq, m);				\
398 			(err) = 0;					\
399 		}							\
400 	}								\
401 	if (err)							\
402 		(ifq)->ifq_drops++;					\
403 	IF_UNLOCK(ifq);							\
404 } while (0)
405 
406 #define	IFQ_DEQUEUE_NOLOCK(ifq, m)					\
407 do {									\
408 	if (TBR_IS_ENABLED(ifq))					\
409 		(m) = tbr_dequeue_ptr(ifq, ALTDQ_REMOVE);		\
410 	else if (ALTQ_IS_ENABLED(ifq))					\
411 		ALTQ_DEQUEUE(ifq, m);					\
412 	else								\
413 		_IF_DEQUEUE(ifq, m);					\
414 } while (0)
415 
416 #define	IFQ_DEQUEUE(ifq, m)						\
417 do {									\
418 	IF_LOCK(ifq);							\
419 	IFQ_DEQUEUE_NOLOCK(ifq, m);					\
420 	IF_UNLOCK(ifq);							\
421 } while (0)
422 
423 #define	IFQ_POLL_NOLOCK(ifq, m)						\
424 do {									\
425 	if (TBR_IS_ENABLED(ifq))					\
426 		(m) = tbr_dequeue_ptr(ifq, ALTDQ_POLL);			\
427 	else if (ALTQ_IS_ENABLED(ifq))					\
428 		ALTQ_POLL(ifq, m);					\
429 	else								\
430 		_IF_POLL(ifq, m);					\
431 } while (0)
432 
433 #define	IFQ_POLL(ifq, m)						\
434 do {									\
435 	IF_LOCK(ifq);							\
436 	IFQ_POLL_NOLOCK(ifq, m);					\
437 	IF_UNLOCK(ifq);							\
438 } while (0)
439 
440 #define	IFQ_PURGE_NOLOCK(ifq)						\
441 do {									\
442 	if (ALTQ_IS_ENABLED(ifq)) {					\
443 		ALTQ_PURGE(ifq);					\
444 	} else								\
445 		_IF_DRAIN(ifq);						\
446 } while (0)
447 
448 #define	IFQ_PURGE(ifq)							\
449 do {									\
450 	IF_LOCK(ifq);							\
451 	IFQ_PURGE_NOLOCK(ifq);						\
452 	IF_UNLOCK(ifq);							\
453 } while (0)
454 
455 #define	IFQ_SET_READY(ifq)						\
456 	do { ((ifq)->altq_flags |= ALTQF_READY); } while (0)
457 
458 #define	IFQ_LOCK(ifq)			IF_LOCK(ifq)
459 #define	IFQ_UNLOCK(ifq)			IF_UNLOCK(ifq)
460 #define	IFQ_LOCK_ASSERT(ifq)		IF_LOCK_ASSERT(ifq)
461 #define	IFQ_IS_EMPTY(ifq)		((ifq)->ifq_len == 0)
462 #define	IFQ_INC_LEN(ifq)		((ifq)->ifq_len++)
463 #define	IFQ_DEC_LEN(ifq)		(--(ifq)->ifq_len)
464 #define	IFQ_INC_DROPS(ifq)		((ifq)->ifq_drops++)
465 #define	IFQ_SET_MAXLEN(ifq, len)	((ifq)->ifq_maxlen = (len))
466 
467 /*
468  * The IFF_DRV_OACTIVE test should really occur in the device driver, not in
469  * the handoff logic, as that flag is locked by the device driver.
470  */
471 #define	IFQ_HANDOFF_ADJ(ifp, m, adj, err)				\
472 do {									\
473 	int len;							\
474 	short mflags;							\
475 									\
476 	len = (m)->m_pkthdr.len;					\
477 	mflags = (m)->m_flags;						\
478 	IFQ_ENQUEUE(&(ifp)->if_snd, m, err);				\
479 	if ((err) == 0) {						\
480 		(ifp)->if_obytes += len + (adj);			\
481 		if (mflags & M_MCAST)					\
482 			(ifp)->if_omcasts++;				\
483 		if (((ifp)->if_drv_flags & IFF_DRV_OACTIVE) == 0)	\
484 			if_start(ifp);					\
485 	}								\
486 } while (0)
487 
488 #define	IFQ_HANDOFF(ifp, m, err)					\
489 	IFQ_HANDOFF_ADJ(ifp, m, 0, err)
490 
491 #define	IFQ_DRV_DEQUEUE(ifq, m)						\
492 do {									\
493 	(m) = (ifq)->ifq_drv_head;					\
494 	if (m) {							\
495 		if (((ifq)->ifq_drv_head = (m)->m_nextpkt) == NULL)	\
496 			(ifq)->ifq_drv_tail = NULL;			\
497 		(m)->m_nextpkt = NULL;					\
498 		(ifq)->ifq_drv_len--;					\
499 	} else {							\
500 		IFQ_LOCK(ifq);						\
501 		IFQ_DEQUEUE_NOLOCK(ifq, m);				\
502 		while ((ifq)->ifq_drv_len < (ifq)->ifq_drv_maxlen) {	\
503 			struct mbuf *m0;				\
504 			IFQ_DEQUEUE_NOLOCK(ifq, m0);			\
505 			if (m0 == NULL)					\
506 				break;					\
507 			m0->m_nextpkt = NULL;				\
508 			if ((ifq)->ifq_drv_tail == NULL)		\
509 				(ifq)->ifq_drv_head = m0;		\
510 			else						\
511 				(ifq)->ifq_drv_tail->m_nextpkt = m0;	\
512 			(ifq)->ifq_drv_tail = m0;			\
513 			(ifq)->ifq_drv_len++;				\
514 		}							\
515 		IFQ_UNLOCK(ifq);					\
516 	}								\
517 } while (0)
518 
519 #define	IFQ_DRV_PREPEND(ifq, m)						\
520 do {									\
521 	(m)->m_nextpkt = (ifq)->ifq_drv_head;				\
522 	if ((ifq)->ifq_drv_tail == NULL)				\
523 		(ifq)->ifq_drv_tail = (m);				\
524 	(ifq)->ifq_drv_head = (m);					\
525 	(ifq)->ifq_drv_len++;						\
526 } while (0)
527 
528 #define	IFQ_DRV_IS_EMPTY(ifq)						\
529 	(((ifq)->ifq_drv_len == 0) && ((ifq)->ifq_len == 0))
530 
531 #define	IFQ_DRV_PURGE(ifq)						\
532 do {									\
533 	struct mbuf *m, *n = (ifq)->ifq_drv_head;			\
534 	while((m = n) != NULL) {					\
535 		n = m->m_nextpkt;					\
536 		m_freem(m);						\
537 	}								\
538 	(ifq)->ifq_drv_head = (ifq)->ifq_drv_tail = NULL;		\
539 	(ifq)->ifq_drv_len = 0;						\
540 	IFQ_PURGE(ifq);							\
541 } while (0)
542 
543 /*
544  * 72 was chosen below because it is the size of a TCP/IP
545  * header (40) + the minimum mss (32).
546  */
547 #define	IF_MINMTU	72
548 #define	IF_MAXMTU	65535
549 
550 #endif /* _KERNEL */
551 
552 /*
553  * The ifaddr structure contains information about one address
554  * of an interface.  They are maintained by the different address families,
555  * are allocated and attached when an address is set, and are linked
556  * together so all addresses for an interface can be located.
557  *
558  * NOTE: a 'struct ifaddr' is always at the beginning of a larger
559  * chunk of malloc'ed memory, where we store the three addresses
560  * (ifa_addr, ifa_dstaddr and ifa_netmask) referenced here.
561  */
562 struct ifaddr {
563 	struct	sockaddr *ifa_addr;	/* address of interface */
564 	struct	sockaddr *ifa_dstaddr;	/* other end of p-to-p link */
565 #define	ifa_broadaddr	ifa_dstaddr	/* broadcast address interface */
566 	struct	sockaddr *ifa_netmask;	/* used to determine subnet */
567 	struct	if_data if_data;	/* not all members are meaningful */
568 	struct	ifnet *ifa_ifp;		/* back-pointer to interface */
569 	TAILQ_ENTRY(ifaddr) ifa_link;	/* queue macro glue */
570 	void	(*ifa_rtrequest)	/* check or clean routes (+ or -)'d */
571 		(int, struct rtentry *, struct rt_addrinfo *);
572 	u_short	ifa_flags;		/* mostly rt_flags for cloning */
573 	u_int	ifa_refcnt;		/* references to this structure */
574 	int	ifa_metric;		/* cost of going out this interface */
575 	int (*ifa_claim_addr)		/* check if an addr goes to this if */
576 		(struct ifaddr *, struct sockaddr *);
577 	struct mtx ifa_mtx;
578 };
579 #define	IFA_ROUTE	RTF_UP		/* route installed */
580 
581 /* for compatibility with other BSDs */
582 #define	ifa_list	ifa_link
583 
584 #define	IFA_LOCK_INIT(ifa)	\
585     mtx_init(&(ifa)->ifa_mtx, "ifaddr", NULL, MTX_DEF)
586 #define	IFA_LOCK(ifa)		mtx_lock(&(ifa)->ifa_mtx)
587 #define	IFA_UNLOCK(ifa)		mtx_unlock(&(ifa)->ifa_mtx)
588 #define	IFA_DESTROY(ifa)	mtx_destroy(&(ifa)->ifa_mtx)
589 
590 /*
591  * The prefix structure contains information about one prefix
592  * of an interface.  They are maintained by the different address families,
593  * are allocated and attached when a prefix or an address is set,
594  * and are linked together so all prefixes for an interface can be located.
595  */
596 struct ifprefix {
597 	struct	sockaddr *ifpr_prefix;	/* prefix of interface */
598 	struct	ifnet *ifpr_ifp;	/* back-pointer to interface */
599 	TAILQ_ENTRY(ifprefix) ifpr_list; /* queue macro glue */
600 	u_char	ifpr_plen;		/* prefix length in bits */
601 	u_char	ifpr_type;		/* protocol dependent prefix type */
602 };
603 
604 /*
605  * Multicast address structure.  This is analogous to the ifaddr
606  * structure except that it keeps track of multicast addresses.
607  */
608 struct ifmultiaddr {
609 	TAILQ_ENTRY(ifmultiaddr) ifma_link; /* queue macro glue */
610 	struct	sockaddr *ifma_addr; 	/* address this membership is for */
611 	struct	sockaddr *ifma_lladdr;	/* link-layer translation, if any */
612 	struct	ifnet *ifma_ifp;	/* back-pointer to interface */
613 	u_int	ifma_refcount;		/* reference count */
614 	void	*ifma_protospec;	/* protocol-specific state, if any */
615 	struct	ifmultiaddr *ifma_llifma; /* pointer to ifma for ifma_lladdr */
616 };
617 
618 #ifdef _KERNEL
619 #define	IFAFREE(ifa)					\
620 	do {						\
621 		IFA_LOCK(ifa);				\
622 		KASSERT((ifa)->ifa_refcnt > 0,		\
623 		    ("ifa %p !(ifa_refcnt > 0)", ifa));	\
624 		if (--(ifa)->ifa_refcnt == 0) {		\
625 			IFA_DESTROY(ifa);		\
626 			free(ifa, M_IFADDR);		\
627 		} else 					\
628 			IFA_UNLOCK(ifa);		\
629 	} while (0)
630 
631 #define IFAREF(ifa)					\
632 	do {						\
633 		IFA_LOCK(ifa);				\
634 		++(ifa)->ifa_refcnt;			\
635 		IFA_UNLOCK(ifa);			\
636 	} while (0)
637 
638 extern	struct mtx ifnet_lock;
639 #define	IFNET_LOCK_INIT() \
640     mtx_init(&ifnet_lock, "ifnet", NULL, MTX_DEF | MTX_RECURSE)
641 #define	IFNET_WLOCK()		mtx_lock(&ifnet_lock)
642 #define	IFNET_WUNLOCK()		mtx_unlock(&ifnet_lock)
643 #define	IFNET_WLOCK_ASSERT()	mtx_assert(&ifnet_lock, MA_OWNED)
644 #define	IFNET_RLOCK()		IFNET_WLOCK()
645 #define	IFNET_RUNLOCK()		IFNET_WUNLOCK()
646 
647 struct ifindex_entry {
648 	struct	ifnet *ife_ifnet;
649 	struct cdev *ife_dev;
650 };
651 
652 struct ifnet	*ifnet_byindex(u_short idx);
653 
654 /*
655  * Given the index, ifaddr_byindex() returns the one and only
656  * link-level ifaddr for the interface. You are not supposed to use
657  * it to traverse the list of addresses associated to the interface.
658  */
659 struct ifaddr	*ifaddr_byindex(u_short idx);
660 struct cdev	*ifdev_byindex(u_short idx);
661 
662 #ifdef VIMAGE_GLOBALS
663 extern	struct ifnethead ifnet;
664 extern	struct ifnet *loif;	/* first loopback interface */
665 extern	int if_index;
666 #endif
667 extern	int ifqmaxlen;
668 
669 int	if_addgroup(struct ifnet *, const char *);
670 int	if_delgroup(struct ifnet *, const char *);
671 int	if_addmulti(struct ifnet *, struct sockaddr *, struct ifmultiaddr **);
672 int	if_allmulti(struct ifnet *, int);
673 struct	ifnet* if_alloc(u_char);
674 void	if_attach(struct ifnet *);
675 int	if_delmulti(struct ifnet *, struct sockaddr *);
676 void	if_delmulti_ifma(struct ifmultiaddr *);
677 void	if_detach(struct ifnet *);
678 void	if_purgeaddrs(struct ifnet *);
679 void	if_purgemaddrs(struct ifnet *);
680 void	if_down(struct ifnet *);
681 struct ifmultiaddr *
682 	if_findmulti(struct ifnet *, struct sockaddr *);
683 void	if_free(struct ifnet *);
684 void	if_free_type(struct ifnet *, u_char);
685 void	if_initname(struct ifnet *, const char *, int);
686 void	if_link_state_change(struct ifnet *, int);
687 int	if_printf(struct ifnet *, const char *, ...) __printflike(2, 3);
688 int	if_setlladdr(struct ifnet *, const u_char *, int);
689 void	if_up(struct ifnet *);
690 /*void	ifinit(void);*/ /* declared in systm.h for main() */
691 int	ifioctl(struct socket *, u_long, caddr_t, struct thread *);
692 int	ifpromisc(struct ifnet *, int);
693 struct	ifnet *ifunit(const char *);
694 
695 void	ifq_attach(struct ifaltq *, struct ifnet *ifp);
696 void	ifq_detach(struct ifaltq *);
697 
698 struct	ifaddr *ifa_ifwithaddr(struct sockaddr *);
699 struct	ifaddr *ifa_ifwithbroadaddr(struct sockaddr *);
700 struct	ifaddr *ifa_ifwithdstaddr(struct sockaddr *);
701 struct	ifaddr *ifa_ifwithnet(struct sockaddr *);
702 struct	ifaddr *ifa_ifwithroute(int, struct sockaddr *, struct sockaddr *);
703 struct	ifaddr *ifa_ifwithroute_fib(int, struct sockaddr *, struct sockaddr *, u_int);
704 
705 struct	ifaddr *ifaof_ifpforaddr(struct sockaddr *, struct ifnet *);
706 
707 int	if_simloop(struct ifnet *ifp, struct mbuf *m, int af, int hlen);
708 
709 typedef	void *if_com_alloc_t(u_char type, struct ifnet *ifp);
710 typedef	void if_com_free_t(void *com, u_char type);
711 void	if_register_com_alloc(u_char type, if_com_alloc_t *a, if_com_free_t *f);
712 void	if_deregister_com_alloc(u_char type);
713 
714 #define IF_LLADDR(ifp)							\
715     LLADDR((struct sockaddr_dl *)((ifp)->if_addr->ifa_addr))
716 
717 #ifdef DEVICE_POLLING
718 enum poll_cmd {	POLL_ONLY, POLL_AND_CHECK_STATUS };
719 
720 typedef	void poll_handler_t(struct ifnet *ifp, enum poll_cmd cmd, int count);
721 int    ether_poll_register(poll_handler_t *h, struct ifnet *ifp);
722 int    ether_poll_deregister(struct ifnet *ifp);
723 #endif /* DEVICE_POLLING */
724 
725 #endif /* _KERNEL */
726 
727 #endif /* !_NET_IF_VAR_H_ */
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