xref: /freebsd/sys/net/if_var.h (revision 830940567b49bb0c08dfaed40418999e76616909)
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 struct	route;
74 struct	vnet;
75 #endif
76 
77 #include <sys/queue.h>		/* get TAILQ macros */
78 
79 #ifdef _KERNEL
80 #include <sys/mbuf.h>
81 #include <sys/eventhandler.h>
82 #include <sys/buf_ring.h>
83 #include <net/vnet.h>
84 #endif /* _KERNEL */
85 #include <sys/lock.h>		/* XXX */
86 #include <sys/mutex.h>		/* XXX */
87 #include <sys/rwlock.h>		/* XXX */
88 #include <sys/event.h>		/* XXX */
89 #include <sys/_task.h>
90 
91 #define	IF_DUNIT_NONE	-1
92 
93 #include <altq/if_altq.h>
94 
95 TAILQ_HEAD(ifnethead, ifnet);	/* we use TAILQs so that the order of */
96 TAILQ_HEAD(ifaddrhead, ifaddr);	/* instantiation is preserved in the list */
97 TAILQ_HEAD(ifprefixhead, ifprefix);
98 TAILQ_HEAD(ifmultihead, ifmultiaddr);
99 TAILQ_HEAD(ifgrouphead, ifg_group);
100 
101 /*
102  * Structure defining a queue for a network interface.
103  */
104 struct	ifqueue {
105 	struct	mbuf *ifq_head;
106 	struct	mbuf *ifq_tail;
107 	int	ifq_len;
108 	int	ifq_maxlen;
109 	int	ifq_drops;
110 	struct	mtx ifq_mtx;
111 };
112 
113 /*
114  * Structure defining a network interface.
115  *
116  * (Would like to call this struct ``if'', but C isn't PL/1.)
117  */
118 
119 struct ifnet {
120 	void	*if_softc;		/* pointer to driver state */
121 	void	*if_l2com;		/* pointer to protocol bits */
122 	struct vnet *if_vnet;		/* pointer to network stack instance */
123 	TAILQ_ENTRY(ifnet) if_link; 	/* all struct ifnets are chained */
124 	char	if_xname[IFNAMSIZ];	/* external name (name + unit) */
125 	const char *if_dname;		/* driver name */
126 	int	if_dunit;		/* unit or IF_DUNIT_NONE */
127 	u_int	if_refcount;		/* reference count */
128 	struct	ifaddrhead if_addrhead;	/* linked list of addresses per if */
129 		/*
130 		 * if_addrhead is the list of all addresses associated to
131 		 * an interface.
132 		 * Some code in the kernel assumes that first element
133 		 * of the list has type AF_LINK, and contains sockaddr_dl
134 		 * addresses which store the link-level address and the name
135 		 * of the interface.
136 		 * However, access to the AF_LINK address through this
137 		 * field is deprecated. Use if_addr or ifaddr_byindex() instead.
138 		 */
139 	int	if_pcount;		/* number of promiscuous listeners */
140 	struct	carp_if *if_carp;	/* carp interface structure */
141 	struct	bpf_if *if_bpf;		/* packet filter structure */
142 	u_short	if_index;		/* numeric abbreviation for this if  */
143 	short	if_timer;		/* time 'til if_watchdog called */
144 	struct  ifvlantrunk *if_vlantrunk; /* pointer to 802.1q data */
145 	int	if_flags;		/* up/down, broadcast, etc. */
146 	int	if_capabilities;	/* interface features & capabilities */
147 	int	if_capenable;		/* enabled features & capabilities */
148 	void	*if_linkmib;		/* link-type-specific MIB data */
149 	size_t	if_linkmiblen;		/* length of above data */
150 	struct	if_data if_data;
151 	struct	ifmultihead if_multiaddrs; /* multicast addresses configured */
152 	int	if_amcount;		/* number of all-multicast requests */
153 /* procedure handles */
154 	int	(*if_output)		/* output routine (enqueue) */
155 		(struct ifnet *, struct mbuf *, struct sockaddr *,
156 		     struct route *);
157 	void	(*if_input)		/* input routine (from h/w driver) */
158 		(struct ifnet *, struct mbuf *);
159 	void	(*if_start)		/* initiate output routine */
160 		(struct ifnet *);
161 	int	(*if_ioctl)		/* ioctl routine */
162 		(struct ifnet *, u_long, caddr_t);
163 	void	(*if_watchdog)		/* timer routine */
164 		(struct ifnet *);
165 	void	(*if_init)		/* Init routine */
166 		(void *);
167 	int	(*if_resolvemulti)	/* validate/resolve multicast */
168 		(struct ifnet *, struct sockaddr **, struct sockaddr *);
169 	void	(*if_qflush)		/* flush any queues */
170 		(struct ifnet *);
171 	int	(*if_transmit)		/* initiate output routine */
172 		(struct ifnet *, struct mbuf *);
173 	void	(*if_reassign)		/* reassign to vnet routine */
174 		(struct ifnet *, struct vnet *, char *);
175 	struct	vnet *if_home_vnet;	/* where this ifnet originates from */
176 	struct	ifaddr	*if_addr;	/* pointer to link-level address */
177 	void	*if_llsoftc;		/* link layer softc */
178 	int	if_drv_flags;		/* driver-managed status flags */
179 	struct  ifaltq if_snd;		/* output queue (includes altq) */
180 	const u_int8_t *if_broadcastaddr; /* linklevel broadcast bytestring */
181 
182 	void	*if_bridge;		/* bridge glue */
183 
184 	struct	label *if_label;	/* interface MAC label */
185 
186 	/* these are only used by IPv6 */
187 	struct	ifprefixhead if_prefixhead; /* list of prefixes per if */
188 	void	*if_afdata[AF_MAX];
189 	int	if_afdata_initialized;
190 	struct	rwlock if_afdata_lock;
191 	struct	task if_linktask;	/* task for link change events */
192 	struct	mtx if_addr_mtx;	/* mutex to protect address lists */
193 
194 	LIST_ENTRY(ifnet) if_clones;	/* interfaces of a cloner */
195 	TAILQ_HEAD(, ifg_list) if_groups; /* linked list of groups per if */
196 					/* protected by if_addr_mtx */
197 	void	*if_pf_kif;
198 	void	*if_lagg;		/* lagg glue */
199 	u_char	 if_alloctype;		/* if_type at time of allocation */
200 
201 	/*
202 	 * Spare fields are added so that we can modify sensitive data
203 	 * structures without changing the kernel binary interface, and must
204 	 * be used with care where binary compatibility is required.
205 	 */
206 	char	 if_cspare[3];
207 	void	*if_pspare[8];
208 	int	if_ispare[4];
209 };
210 
211 typedef void if_init_f_t(void *);
212 
213 /*
214  * XXX These aliases are terribly dangerous because they could apply
215  * to anything.
216  */
217 #define	if_mtu		if_data.ifi_mtu
218 #define	if_type		if_data.ifi_type
219 #define if_physical	if_data.ifi_physical
220 #define	if_addrlen	if_data.ifi_addrlen
221 #define	if_hdrlen	if_data.ifi_hdrlen
222 #define	if_metric	if_data.ifi_metric
223 #define	if_link_state	if_data.ifi_link_state
224 #define	if_baudrate	if_data.ifi_baudrate
225 #define	if_hwassist	if_data.ifi_hwassist
226 #define	if_ipackets	if_data.ifi_ipackets
227 #define	if_ierrors	if_data.ifi_ierrors
228 #define	if_opackets	if_data.ifi_opackets
229 #define	if_oerrors	if_data.ifi_oerrors
230 #define	if_collisions	if_data.ifi_collisions
231 #define	if_ibytes	if_data.ifi_ibytes
232 #define	if_obytes	if_data.ifi_obytes
233 #define	if_imcasts	if_data.ifi_imcasts
234 #define	if_omcasts	if_data.ifi_omcasts
235 #define	if_iqdrops	if_data.ifi_iqdrops
236 #define	if_noproto	if_data.ifi_noproto
237 #define	if_lastchange	if_data.ifi_lastchange
238 
239 /* for compatibility with other BSDs */
240 #define	if_addrlist	if_addrhead
241 #define	if_list		if_link
242 #define	if_name(ifp)	((ifp)->if_xname)
243 
244 /*
245  * Locks for address lists on the network interface.
246  */
247 #define	IF_ADDR_LOCK_INIT(if)	mtx_init(&(if)->if_addr_mtx,		\
248 				    "if_addr_mtx", NULL, MTX_DEF)
249 #define	IF_ADDR_LOCK_DESTROY(if)	mtx_destroy(&(if)->if_addr_mtx)
250 #define	IF_ADDR_LOCK(if)	mtx_lock(&(if)->if_addr_mtx)
251 #define	IF_ADDR_UNLOCK(if)	mtx_unlock(&(if)->if_addr_mtx)
252 #define	IF_ADDR_LOCK_ASSERT(if)	mtx_assert(&(if)->if_addr_mtx, MA_OWNED)
253 
254 /*
255  * Function variations on locking macros intended to be used by loadable
256  * kernel modules in order to divorce them from the internals of address list
257  * locking.
258  */
259 void	if_addr_rlock(struct ifnet *ifp);	/* if_addrhead */
260 void	if_addr_runlock(struct ifnet *ifp);	/* if_addrhead */
261 void	if_maddr_rlock(struct ifnet *ifp);	/* if_multiaddrs */
262 void	if_maddr_runlock(struct ifnet *ifp);	/* if_multiaddrs */
263 
264 /*
265  * Output queues (ifp->if_snd) and slow device input queues (*ifp->if_slowq)
266  * are queues of messages stored on ifqueue structures
267  * (defined above).  Entries are added to and deleted from these structures
268  * by these macros, which should be called with ipl raised to splimp().
269  */
270 #define IF_LOCK(ifq)		mtx_lock(&(ifq)->ifq_mtx)
271 #define IF_UNLOCK(ifq)		mtx_unlock(&(ifq)->ifq_mtx)
272 #define	IF_LOCK_ASSERT(ifq)	mtx_assert(&(ifq)->ifq_mtx, MA_OWNED)
273 #define	_IF_QFULL(ifq)		((ifq)->ifq_len >= (ifq)->ifq_maxlen)
274 #define	_IF_DROP(ifq)		((ifq)->ifq_drops++)
275 #define	_IF_QLEN(ifq)		((ifq)->ifq_len)
276 
277 #define	_IF_ENQUEUE(ifq, m) do { 				\
278 	(m)->m_nextpkt = NULL;					\
279 	if ((ifq)->ifq_tail == NULL) 				\
280 		(ifq)->ifq_head = m; 				\
281 	else 							\
282 		(ifq)->ifq_tail->m_nextpkt = m; 		\
283 	(ifq)->ifq_tail = m; 					\
284 	(ifq)->ifq_len++; 					\
285 } while (0)
286 
287 #define IF_ENQUEUE(ifq, m) do {					\
288 	IF_LOCK(ifq); 						\
289 	_IF_ENQUEUE(ifq, m); 					\
290 	IF_UNLOCK(ifq); 					\
291 } while (0)
292 
293 #define	_IF_PREPEND(ifq, m) do {				\
294 	(m)->m_nextpkt = (ifq)->ifq_head; 			\
295 	if ((ifq)->ifq_tail == NULL) 				\
296 		(ifq)->ifq_tail = (m); 				\
297 	(ifq)->ifq_head = (m); 					\
298 	(ifq)->ifq_len++; 					\
299 } while (0)
300 
301 #define IF_PREPEND(ifq, m) do {		 			\
302 	IF_LOCK(ifq); 						\
303 	_IF_PREPEND(ifq, m); 					\
304 	IF_UNLOCK(ifq); 					\
305 } while (0)
306 
307 #define	_IF_DEQUEUE(ifq, m) do { 				\
308 	(m) = (ifq)->ifq_head; 					\
309 	if (m) { 						\
310 		if (((ifq)->ifq_head = (m)->m_nextpkt) == NULL)	\
311 			(ifq)->ifq_tail = NULL; 		\
312 		(m)->m_nextpkt = NULL; 				\
313 		(ifq)->ifq_len--; 				\
314 	} 							\
315 } while (0)
316 
317 #define IF_DEQUEUE(ifq, m) do { 				\
318 	IF_LOCK(ifq); 						\
319 	_IF_DEQUEUE(ifq, m); 					\
320 	IF_UNLOCK(ifq); 					\
321 } while (0)
322 
323 #define	_IF_POLL(ifq, m)	((m) = (ifq)->ifq_head)
324 #define	IF_POLL(ifq, m)		_IF_POLL(ifq, m)
325 
326 #define _IF_DRAIN(ifq) do { 					\
327 	struct mbuf *m; 					\
328 	for (;;) { 						\
329 		_IF_DEQUEUE(ifq, m); 				\
330 		if (m == NULL) 					\
331 			break; 					\
332 		m_freem(m); 					\
333 	} 							\
334 } while (0)
335 
336 #define IF_DRAIN(ifq) do {					\
337 	IF_LOCK(ifq);						\
338 	_IF_DRAIN(ifq);						\
339 	IF_UNLOCK(ifq);						\
340 } while(0)
341 
342 #ifdef _KERNEL
343 /* interface address change event */
344 typedef void (*ifaddr_event_handler_t)(void *, struct ifnet *);
345 EVENTHANDLER_DECLARE(ifaddr_event, ifaddr_event_handler_t);
346 /* new interface arrival event */
347 typedef void (*ifnet_arrival_event_handler_t)(void *, struct ifnet *);
348 EVENTHANDLER_DECLARE(ifnet_arrival_event, ifnet_arrival_event_handler_t);
349 /* interface departure event */
350 typedef void (*ifnet_departure_event_handler_t)(void *, struct ifnet *);
351 EVENTHANDLER_DECLARE(ifnet_departure_event, ifnet_departure_event_handler_t);
352 
353 /*
354  * interface groups
355  */
356 struct ifg_group {
357 	char				 ifg_group[IFNAMSIZ];
358 	u_int				 ifg_refcnt;
359 	void				*ifg_pf_kif;
360 	TAILQ_HEAD(, ifg_member)	 ifg_members;
361 	TAILQ_ENTRY(ifg_group)		 ifg_next;
362 };
363 
364 struct ifg_member {
365 	TAILQ_ENTRY(ifg_member)	 ifgm_next;
366 	struct ifnet		*ifgm_ifp;
367 };
368 
369 struct ifg_list {
370 	struct ifg_group	*ifgl_group;
371 	TAILQ_ENTRY(ifg_list)	 ifgl_next;
372 };
373 
374 /* group attach event */
375 typedef void (*group_attach_event_handler_t)(void *, struct ifg_group *);
376 EVENTHANDLER_DECLARE(group_attach_event, group_attach_event_handler_t);
377 /* group detach event */
378 typedef void (*group_detach_event_handler_t)(void *, struct ifg_group *);
379 EVENTHANDLER_DECLARE(group_detach_event, group_detach_event_handler_t);
380 /* group change event */
381 typedef void (*group_change_event_handler_t)(void *, const char *);
382 EVENTHANDLER_DECLARE(group_change_event, group_change_event_handler_t);
383 
384 #define	IF_AFDATA_LOCK_INIT(ifp)	\
385 	rw_init(&(ifp)->if_afdata_lock, "if_afdata")
386 
387 #define	IF_AFDATA_WLOCK(ifp)	rw_wlock(&(ifp)->if_afdata_lock)
388 #define	IF_AFDATA_RLOCK(ifp)	rw_rlock(&(ifp)->if_afdata_lock)
389 #define	IF_AFDATA_WUNLOCK(ifp)	rw_wunlock(&(ifp)->if_afdata_lock)
390 #define	IF_AFDATA_RUNLOCK(ifp)	rw_runlock(&(ifp)->if_afdata_lock)
391 #define	IF_AFDATA_LOCK(ifp)	IF_AFDATA_WLOCK(ifp)
392 #define	IF_AFDATA_UNLOCK(ifp)	IF_AFDATA_WUNLOCK(ifp)
393 #define	IF_AFDATA_TRYLOCK(ifp)	rw_try_wlock(&(ifp)->if_afdata_lock)
394 #define	IF_AFDATA_DESTROY(ifp)	rw_destroy(&(ifp)->if_afdata_lock)
395 
396 #define	IF_AFDATA_LOCK_ASSERT(ifp)	rw_assert(&(ifp)->if_afdata_lock, RA_LOCKED)
397 #define	IF_AFDATA_UNLOCK_ASSERT(ifp)	rw_assert(&(ifp)->if_afdata_lock, RA_UNLOCKED)
398 
399 int	if_handoff(struct ifqueue *ifq, struct mbuf *m, struct ifnet *ifp,
400 	    int adjust);
401 #define	IF_HANDOFF(ifq, m, ifp)			\
402 	if_handoff((struct ifqueue *)ifq, m, ifp, 0)
403 #define	IF_HANDOFF_ADJ(ifq, m, ifp, adj)	\
404 	if_handoff((struct ifqueue *)ifq, m, ifp, adj)
405 
406 void	if_start(struct ifnet *);
407 
408 #define	IFQ_ENQUEUE(ifq, m, err)					\
409 do {									\
410 	IF_LOCK(ifq);							\
411 	if (ALTQ_IS_ENABLED(ifq))					\
412 		ALTQ_ENQUEUE(ifq, m, NULL, err);			\
413 	else {								\
414 		if (_IF_QFULL(ifq)) {					\
415 			m_freem(m);					\
416 			(err) = ENOBUFS;				\
417 		} else {						\
418 			_IF_ENQUEUE(ifq, m);				\
419 			(err) = 0;					\
420 		}							\
421 	}								\
422 	if (err)							\
423 		(ifq)->ifq_drops++;					\
424 	IF_UNLOCK(ifq);							\
425 } while (0)
426 
427 #define	IFQ_DEQUEUE_NOLOCK(ifq, m)					\
428 do {									\
429 	if (TBR_IS_ENABLED(ifq))					\
430 		(m) = tbr_dequeue_ptr(ifq, ALTDQ_REMOVE);		\
431 	else if (ALTQ_IS_ENABLED(ifq))					\
432 		ALTQ_DEQUEUE(ifq, m);					\
433 	else								\
434 		_IF_DEQUEUE(ifq, m);					\
435 } while (0)
436 
437 #define	IFQ_DEQUEUE(ifq, m)						\
438 do {									\
439 	IF_LOCK(ifq);							\
440 	IFQ_DEQUEUE_NOLOCK(ifq, m);					\
441 	IF_UNLOCK(ifq);							\
442 } while (0)
443 
444 #define	IFQ_POLL_NOLOCK(ifq, m)						\
445 do {									\
446 	if (TBR_IS_ENABLED(ifq))					\
447 		(m) = tbr_dequeue_ptr(ifq, ALTDQ_POLL);			\
448 	else if (ALTQ_IS_ENABLED(ifq))					\
449 		ALTQ_POLL(ifq, m);					\
450 	else								\
451 		_IF_POLL(ifq, m);					\
452 } while (0)
453 
454 #define	IFQ_POLL(ifq, m)						\
455 do {									\
456 	IF_LOCK(ifq);							\
457 	IFQ_POLL_NOLOCK(ifq, m);					\
458 	IF_UNLOCK(ifq);							\
459 } while (0)
460 
461 #define	IFQ_PURGE_NOLOCK(ifq)						\
462 do {									\
463 	if (ALTQ_IS_ENABLED(ifq)) {					\
464 		ALTQ_PURGE(ifq);					\
465 	} else								\
466 		_IF_DRAIN(ifq);						\
467 } while (0)
468 
469 #define	IFQ_PURGE(ifq)							\
470 do {									\
471 	IF_LOCK(ifq);							\
472 	IFQ_PURGE_NOLOCK(ifq);						\
473 	IF_UNLOCK(ifq);							\
474 } while (0)
475 
476 #define	IFQ_SET_READY(ifq)						\
477 	do { ((ifq)->altq_flags |= ALTQF_READY); } while (0)
478 
479 #define	IFQ_LOCK(ifq)			IF_LOCK(ifq)
480 #define	IFQ_UNLOCK(ifq)			IF_UNLOCK(ifq)
481 #define	IFQ_LOCK_ASSERT(ifq)		IF_LOCK_ASSERT(ifq)
482 #define	IFQ_IS_EMPTY(ifq)		((ifq)->ifq_len == 0)
483 #define	IFQ_INC_LEN(ifq)		((ifq)->ifq_len++)
484 #define	IFQ_DEC_LEN(ifq)		(--(ifq)->ifq_len)
485 #define	IFQ_INC_DROPS(ifq)		((ifq)->ifq_drops++)
486 #define	IFQ_SET_MAXLEN(ifq, len)	((ifq)->ifq_maxlen = (len))
487 
488 /*
489  * The IFF_DRV_OACTIVE test should really occur in the device driver, not in
490  * the handoff logic, as that flag is locked by the device driver.
491  */
492 #define	IFQ_HANDOFF_ADJ(ifp, m, adj, err)				\
493 do {									\
494 	int len;							\
495 	short mflags;							\
496 									\
497 	len = (m)->m_pkthdr.len;					\
498 	mflags = (m)->m_flags;						\
499 	IFQ_ENQUEUE(&(ifp)->if_snd, m, err);				\
500 	if ((err) == 0) {						\
501 		(ifp)->if_obytes += len + (adj);			\
502 		if (mflags & M_MCAST)					\
503 			(ifp)->if_omcasts++;				\
504 		if (((ifp)->if_drv_flags & IFF_DRV_OACTIVE) == 0)	\
505 			if_start(ifp);					\
506 	}								\
507 } while (0)
508 
509 #define	IFQ_HANDOFF(ifp, m, err)					\
510 	IFQ_HANDOFF_ADJ(ifp, m, 0, err)
511 
512 #define	IFQ_DRV_DEQUEUE(ifq, m)						\
513 do {									\
514 	(m) = (ifq)->ifq_drv_head;					\
515 	if (m) {							\
516 		if (((ifq)->ifq_drv_head = (m)->m_nextpkt) == NULL)	\
517 			(ifq)->ifq_drv_tail = NULL;			\
518 		(m)->m_nextpkt = NULL;					\
519 		(ifq)->ifq_drv_len--;					\
520 	} else {							\
521 		IFQ_LOCK(ifq);						\
522 		IFQ_DEQUEUE_NOLOCK(ifq, m);				\
523 		while ((ifq)->ifq_drv_len < (ifq)->ifq_drv_maxlen) {	\
524 			struct mbuf *m0;				\
525 			IFQ_DEQUEUE_NOLOCK(ifq, m0);			\
526 			if (m0 == NULL)					\
527 				break;					\
528 			m0->m_nextpkt = NULL;				\
529 			if ((ifq)->ifq_drv_tail == NULL)		\
530 				(ifq)->ifq_drv_head = m0;		\
531 			else						\
532 				(ifq)->ifq_drv_tail->m_nextpkt = m0;	\
533 			(ifq)->ifq_drv_tail = m0;			\
534 			(ifq)->ifq_drv_len++;				\
535 		}							\
536 		IFQ_UNLOCK(ifq);					\
537 	}								\
538 } while (0)
539 
540 #define	IFQ_DRV_PREPEND(ifq, m)						\
541 do {									\
542 	(m)->m_nextpkt = (ifq)->ifq_drv_head;				\
543 	if ((ifq)->ifq_drv_tail == NULL)				\
544 		(ifq)->ifq_drv_tail = (m);				\
545 	(ifq)->ifq_drv_head = (m);					\
546 	(ifq)->ifq_drv_len++;						\
547 } while (0)
548 
549 #define	IFQ_DRV_IS_EMPTY(ifq)						\
550 	(((ifq)->ifq_drv_len == 0) && ((ifq)->ifq_len == 0))
551 
552 #define	IFQ_DRV_PURGE(ifq)						\
553 do {									\
554 	struct mbuf *m, *n = (ifq)->ifq_drv_head;			\
555 	while((m = n) != NULL) {					\
556 		n = m->m_nextpkt;					\
557 		m_freem(m);						\
558 	}								\
559 	(ifq)->ifq_drv_head = (ifq)->ifq_drv_tail = NULL;		\
560 	(ifq)->ifq_drv_len = 0;						\
561 	IFQ_PURGE(ifq);							\
562 } while (0)
563 
564 #ifdef _KERNEL
565 static __inline void
566 drbr_stats_update(struct ifnet *ifp, int len, int mflags)
567 {
568 #ifndef NO_SLOW_STATS
569 	ifp->if_obytes += len;
570 	if (mflags & M_MCAST)
571 		ifp->if_omcasts++;
572 #endif
573 }
574 
575 static __inline int
576 drbr_enqueue(struct ifnet *ifp, struct buf_ring *br, struct mbuf *m)
577 {
578 	int error = 0;
579 	int len = m->m_pkthdr.len;
580 	int mflags = m->m_flags;
581 
582 #ifdef ALTQ
583 	if (ALTQ_IS_ENABLED(&ifp->if_snd)) {
584 		IFQ_ENQUEUE(&ifp->if_snd, m, error);
585 		return (error);
586 	}
587 #endif
588 	if ((error = buf_ring_enqueue_bytes(br, m, len)) == ENOBUFS) {
589 		br->br_drops++;
590 		m_freem(m);
591 	} else
592 		drbr_stats_update(ifp, len, mflags);
593 
594 	return (error);
595 }
596 
597 static __inline void
598 drbr_flush(struct ifnet *ifp, struct buf_ring *br)
599 {
600 	struct mbuf *m;
601 
602 #ifdef ALTQ
603 	if (ifp != NULL && ALTQ_IS_ENABLED(&ifp->if_snd)) {
604 		while (!IFQ_IS_EMPTY(&ifp->if_snd)) {
605 			IFQ_DRV_DEQUEUE(&ifp->if_snd, m);
606 			m_freem(m);
607 		}
608 	}
609 #endif
610 	while ((m = buf_ring_dequeue_sc(br)) != NULL)
611 		m_freem(m);
612 }
613 
614 static __inline void
615 drbr_free(struct buf_ring *br, struct malloc_type *type)
616 {
617 
618 	drbr_flush(NULL, br);
619 	buf_ring_free(br, type);
620 }
621 
622 static __inline struct mbuf *
623 drbr_dequeue(struct ifnet *ifp, struct buf_ring *br)
624 {
625 #ifdef ALTQ
626 	struct mbuf *m;
627 
628 	if (ALTQ_IS_ENABLED(&ifp->if_snd)) {
629 		IFQ_DRV_DEQUEUE(&ifp->if_snd, m);
630 		return (m);
631 	}
632 #endif
633 	return (buf_ring_dequeue_sc(br));
634 }
635 
636 static __inline struct mbuf *
637 drbr_dequeue_cond(struct ifnet *ifp, struct buf_ring *br,
638     int (*func) (struct mbuf *, void *), void *arg)
639 {
640 	struct mbuf *m;
641 #ifdef ALTQ
642 	/*
643 	 * XXX need to evaluate / requeue
644 	 */
645 	if (ALTQ_IS_ENABLED(&ifp->if_snd)) {
646 		IFQ_DRV_DEQUEUE(&ifp->if_snd, m);
647 		return (m);
648 	}
649 #endif
650 	m = buf_ring_peek(br);
651 	if (m == NULL || func(m, arg) == 0)
652 		return (NULL);
653 
654 	return (buf_ring_dequeue_sc(br));
655 }
656 
657 static __inline int
658 drbr_empty(struct ifnet *ifp, struct buf_ring *br)
659 {
660 #ifdef ALTQ
661 	if (ALTQ_IS_ENABLED(&ifp->if_snd))
662 		return (IFQ_DRV_IS_EMPTY(&ifp->if_snd));
663 #endif
664 	return (buf_ring_empty(br));
665 }
666 
667 static __inline int
668 drbr_inuse(struct ifnet *ifp, struct buf_ring *br)
669 {
670 #ifdef ALTQ
671 	if (ALTQ_IS_ENABLED(&ifp->if_snd))
672 		return (ifp->if_snd.ifq_len);
673 #endif
674 	return (buf_ring_count(br));
675 }
676 #endif
677 /*
678  * 72 was chosen below because it is the size of a TCP/IP
679  * header (40) + the minimum mss (32).
680  */
681 #define	IF_MINMTU	72
682 #define	IF_MAXMTU	65535
683 
684 #endif /* _KERNEL */
685 
686 /*
687  * The ifaddr structure contains information about one address
688  * of an interface.  They are maintained by the different address families,
689  * are allocated and attached when an address is set, and are linked
690  * together so all addresses for an interface can be located.
691  *
692  * NOTE: a 'struct ifaddr' is always at the beginning of a larger
693  * chunk of malloc'ed memory, where we store the three addresses
694  * (ifa_addr, ifa_dstaddr and ifa_netmask) referenced here.
695  */
696 struct ifaddr {
697 	struct	sockaddr *ifa_addr;	/* address of interface */
698 	struct	sockaddr *ifa_dstaddr;	/* other end of p-to-p link */
699 #define	ifa_broadaddr	ifa_dstaddr	/* broadcast address interface */
700 	struct	sockaddr *ifa_netmask;	/* used to determine subnet */
701 	struct	if_data if_data;	/* not all members are meaningful */
702 	struct	ifnet *ifa_ifp;		/* back-pointer to interface */
703 	TAILQ_ENTRY(ifaddr) ifa_link;	/* queue macro glue */
704 	void	(*ifa_rtrequest)	/* check or clean routes (+ or -)'d */
705 		(int, struct rtentry *, struct rt_addrinfo *);
706 	u_short	ifa_flags;		/* mostly rt_flags for cloning */
707 	u_int	ifa_refcnt;		/* references to this structure */
708 	int	ifa_metric;		/* cost of going out this interface */
709 	int (*ifa_claim_addr)		/* check if an addr goes to this if */
710 		(struct ifaddr *, struct sockaddr *);
711 	struct mtx ifa_mtx;
712 };
713 #define	IFA_ROUTE	RTF_UP		/* route installed */
714 
715 /* for compatibility with other BSDs */
716 #define	ifa_list	ifa_link
717 
718 #ifdef _KERNEL
719 #define	IFA_LOCK(ifa)		mtx_lock(&(ifa)->ifa_mtx)
720 #define	IFA_UNLOCK(ifa)		mtx_unlock(&(ifa)->ifa_mtx)
721 
722 void	ifa_free(struct ifaddr *ifa);
723 void	ifa_init(struct ifaddr *ifa);
724 void	ifa_ref(struct ifaddr *ifa);
725 #endif
726 
727 /*
728  * The prefix structure contains information about one prefix
729  * of an interface.  They are maintained by the different address families,
730  * are allocated and attached when a prefix or an address is set,
731  * and are linked together so all prefixes for an interface can be located.
732  */
733 struct ifprefix {
734 	struct	sockaddr *ifpr_prefix;	/* prefix of interface */
735 	struct	ifnet *ifpr_ifp;	/* back-pointer to interface */
736 	TAILQ_ENTRY(ifprefix) ifpr_list; /* queue macro glue */
737 	u_char	ifpr_plen;		/* prefix length in bits */
738 	u_char	ifpr_type;		/* protocol dependent prefix type */
739 };
740 
741 /*
742  * Multicast address structure.  This is analogous to the ifaddr
743  * structure except that it keeps track of multicast addresses.
744  */
745 struct ifmultiaddr {
746 	TAILQ_ENTRY(ifmultiaddr) ifma_link; /* queue macro glue */
747 	struct	sockaddr *ifma_addr; 	/* address this membership is for */
748 	struct	sockaddr *ifma_lladdr;	/* link-layer translation, if any */
749 	struct	ifnet *ifma_ifp;	/* back-pointer to interface */
750 	u_int	ifma_refcount;		/* reference count */
751 	void	*ifma_protospec;	/* protocol-specific state, if any */
752 	struct	ifmultiaddr *ifma_llifma; /* pointer to ifma for ifma_lladdr */
753 };
754 
755 #ifdef _KERNEL
756 
757 extern	struct rwlock ifnet_lock;
758 #define	IFNET_LOCK_INIT() \
759    rw_init_flags(&ifnet_lock, "ifnet",  RW_RECURSE)
760 #define	IFNET_WLOCK()		rw_wlock(&ifnet_lock)
761 #define	IFNET_WUNLOCK()		rw_wunlock(&ifnet_lock)
762 #define	IFNET_WLOCK_ASSERT()	rw_assert(&ifnet_lock, RA_LOCKED)
763 #define	IFNET_RLOCK()		rw_rlock(&ifnet_lock)
764 #define	IFNET_RUNLOCK()		rw_runlock(&ifnet_lock)
765 
766 /*
767  * Look up an ifnet given its index; the _ref variant also acquires a
768  * reference that must be freed using if_rele().  It is almost always a bug
769  * to call ifnet_byindex() instead if ifnet_byindex_ref().
770  */
771 struct ifnet	*ifnet_byindex(u_short idx);
772 struct ifnet	*ifnet_byindex_locked(u_short idx);
773 struct ifnet	*ifnet_byindex_ref(u_short idx);
774 
775 /*
776  * Given the index, ifaddr_byindex() returns the one and only
777  * link-level ifaddr for the interface. You are not supposed to use
778  * it to traverse the list of addresses associated to the interface.
779  */
780 struct ifaddr	*ifaddr_byindex(u_short idx);
781 
782 VNET_DECLARE(struct ifnethead, ifnet);
783 VNET_DECLARE(struct ifgrouphead, ifg_head);
784 VNET_DECLARE(int, if_index);
785 VNET_DECLARE(struct ifnet *, loif);	/* first loopback interface */
786 VNET_DECLARE(int, useloopback);
787 
788 #define	V_ifnet		VNET(ifnet)
789 #define	V_ifg_head	VNET(ifg_head)
790 #define	V_if_index	VNET(if_index)
791 #define	V_loif		VNET(loif)
792 #define	V_useloopback	VNET(useloopback)
793 
794 extern	int ifqmaxlen;
795 
796 int	if_addgroup(struct ifnet *, const char *);
797 int	if_delgroup(struct ifnet *, const char *);
798 int	if_addmulti(struct ifnet *, struct sockaddr *, struct ifmultiaddr **);
799 int	if_allmulti(struct ifnet *, int);
800 struct	ifnet* if_alloc(u_char);
801 void	if_attach(struct ifnet *);
802 void	if_dead(struct ifnet *);
803 void	if_grow(void);
804 int	if_delmulti(struct ifnet *, struct sockaddr *);
805 void	if_delmulti_ifma(struct ifmultiaddr *);
806 void	if_detach(struct ifnet *);
807 void	if_vmove(struct ifnet *, struct vnet *);
808 void	if_purgeaddrs(struct ifnet *);
809 void	if_purgemaddrs(struct ifnet *);
810 void	if_down(struct ifnet *);
811 struct ifmultiaddr *
812 	if_findmulti(struct ifnet *, struct sockaddr *);
813 void	if_free(struct ifnet *);
814 void	if_free_type(struct ifnet *, u_char);
815 void	if_initname(struct ifnet *, const char *, int);
816 void	if_link_state_change(struct ifnet *, int);
817 int	if_printf(struct ifnet *, const char *, ...) __printflike(2, 3);
818 void	if_qflush(struct ifnet *);
819 void	if_ref(struct ifnet *);
820 void	if_rele(struct ifnet *);
821 int	if_setlladdr(struct ifnet *, const u_char *, int);
822 void	if_up(struct ifnet *);
823 /*void	ifinit(void);*/ /* declared in systm.h for main() */
824 int	ifioctl(struct socket *, u_long, caddr_t, struct thread *);
825 int	ifpromisc(struct ifnet *, int);
826 struct	ifnet *ifunit(const char *);
827 struct	ifnet *ifunit_ref(const char *);
828 
829 void	ifq_init(struct ifaltq *, struct ifnet *ifp);
830 void	ifq_delete(struct ifaltq *);
831 
832 struct	ifaddr *ifa_ifwithaddr(struct sockaddr *);
833 int		ifa_ifwithaddr_check(struct sockaddr *);
834 struct	ifaddr *ifa_ifwithbroadaddr(struct sockaddr *);
835 struct	ifaddr *ifa_ifwithdstaddr(struct sockaddr *);
836 struct	ifaddr *ifa_ifwithnet(struct sockaddr *);
837 struct	ifaddr *ifa_ifwithroute(int, struct sockaddr *, struct sockaddr *);
838 struct	ifaddr *ifa_ifwithroute_fib(int, struct sockaddr *, struct sockaddr *, u_int);
839 
840 struct	ifaddr *ifaof_ifpforaddr(struct sockaddr *, struct ifnet *);
841 
842 int	if_simloop(struct ifnet *ifp, struct mbuf *m, int af, int hlen);
843 
844 typedef	void *if_com_alloc_t(u_char type, struct ifnet *ifp);
845 typedef	void if_com_free_t(void *com, u_char type);
846 void	if_register_com_alloc(u_char type, if_com_alloc_t *a, if_com_free_t *f);
847 void	if_deregister_com_alloc(u_char type);
848 
849 #define IF_LLADDR(ifp)							\
850     LLADDR((struct sockaddr_dl *)((ifp)->if_addr->ifa_addr))
851 
852 #ifdef DEVICE_POLLING
853 enum poll_cmd {	POLL_ONLY, POLL_AND_CHECK_STATUS };
854 
855 typedef	int poll_handler_t(struct ifnet *ifp, enum poll_cmd cmd, int count);
856 int    ether_poll_register(poll_handler_t *h, struct ifnet *ifp);
857 int    ether_poll_deregister(struct ifnet *ifp);
858 #endif /* DEVICE_POLLING */
859 
860 #endif /* _KERNEL */
861 
862 #endif /* !_NET_IF_VAR_H_ */
863