xref: /freebsd/sys/net/if_var.h (revision 076ad2f836d5f49dc1375f1677335a48fe0d4b82)
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  * 3. 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 struct	rtentry;		/* ifa_rtrequest */
62 struct	rt_addrinfo;		/* ifa_rtrequest */
63 struct	socket;
64 struct	carp_if;
65 struct	carp_softc;
66 struct  ifvlantrunk;
67 struct	route;			/* if_output */
68 struct	vnet;
69 struct	ifmedia;
70 struct	netmap_adapter;
71 
72 #ifdef _KERNEL
73 #include <sys/mbuf.h>		/* ifqueue only? */
74 #include <sys/buf_ring.h>
75 #include <net/vnet.h>
76 #endif /* _KERNEL */
77 #include <sys/counter.h>
78 #include <sys/lock.h>		/* XXX */
79 #include <sys/mutex.h>		/* struct ifqueue */
80 #include <sys/rwlock.h>		/* XXX */
81 #include <sys/sx.h>		/* XXX */
82 #include <sys/_task.h>		/* if_link_task */
83 
84 #define	IF_DUNIT_NONE	-1
85 
86 #include <net/altq/if_altq.h>
87 
88 TAILQ_HEAD(ifnethead, ifnet);	/* we use TAILQs so that the order of */
89 TAILQ_HEAD(ifaddrhead, ifaddr);	/* instantiation is preserved in the list */
90 TAILQ_HEAD(ifmultihead, ifmultiaddr);
91 TAILQ_HEAD(ifgrouphead, ifg_group);
92 
93 #ifdef _KERNEL
94 VNET_DECLARE(struct pfil_head, link_pfil_hook);	/* packet filter hooks */
95 #define	V_link_pfil_hook	VNET(link_pfil_hook)
96 
97 #define	HHOOK_IPSEC_INET	0
98 #define	HHOOK_IPSEC_INET6	1
99 #define	HHOOK_IPSEC_COUNT	2
100 VNET_DECLARE(struct hhook_head *, ipsec_hhh_in[HHOOK_IPSEC_COUNT]);
101 VNET_DECLARE(struct hhook_head *, ipsec_hhh_out[HHOOK_IPSEC_COUNT]);
102 #define	V_ipsec_hhh_in	VNET(ipsec_hhh_in)
103 #define	V_ipsec_hhh_out	VNET(ipsec_hhh_out)
104 #endif /* _KERNEL */
105 
106 typedef enum {
107 	IFCOUNTER_IPACKETS = 0,
108 	IFCOUNTER_IERRORS,
109 	IFCOUNTER_OPACKETS,
110 	IFCOUNTER_OERRORS,
111 	IFCOUNTER_COLLISIONS,
112 	IFCOUNTER_IBYTES,
113 	IFCOUNTER_OBYTES,
114 	IFCOUNTER_IMCASTS,
115 	IFCOUNTER_OMCASTS,
116 	IFCOUNTER_IQDROPS,
117 	IFCOUNTER_OQDROPS,
118 	IFCOUNTER_NOPROTO,
119 	IFCOUNTERS /* Array size. */
120 } ift_counter;
121 
122 typedef struct ifnet * if_t;
123 
124 typedef	void (*if_start_fn_t)(if_t);
125 typedef	int (*if_ioctl_fn_t)(if_t, u_long, caddr_t);
126 typedef	void (*if_init_fn_t)(void *);
127 typedef void (*if_qflush_fn_t)(if_t);
128 typedef int (*if_transmit_fn_t)(if_t, struct mbuf *);
129 typedef	uint64_t (*if_get_counter_t)(if_t, ift_counter);
130 
131 struct ifnet_hw_tsomax {
132 	u_int	tsomaxbytes;	/* TSO total burst length limit in bytes */
133 	u_int	tsomaxsegcount;	/* TSO maximum segment count */
134 	u_int	tsomaxsegsize;	/* TSO maximum segment size in bytes */
135 };
136 
137 /* Interface encap request types */
138 typedef enum {
139 	IFENCAP_LL = 1			/* pre-calculate link-layer header */
140 } ife_type;
141 
142 /*
143  * The structure below allows to request various pre-calculated L2/L3 headers
144  * for different media. Requests varies by type (rtype field).
145  *
146  * IFENCAP_LL type: pre-calculates link header based on address family
147  *   and destination lladdr.
148  *
149  *   Input data fields:
150  *     buf: pointer to destination buffer
151  *     bufsize: buffer size
152  *     flags: IFENCAP_FLAG_BROADCAST if destination is broadcast
153  *     family: address family defined by AF_ constant.
154  *     lladdr: pointer to link-layer address
155  *     lladdr_len: length of link-layer address
156  *     hdata: pointer to L3 header (optional, used for ARP requests).
157  *   Output data fields:
158  *     buf: encap data is stored here
159  *     bufsize: resulting encap length is stored here
160  *     lladdr_off: offset of link-layer address from encap hdr start
161  *     hdata: L3 header may be altered if necessary
162  */
163 
164 struct if_encap_req {
165 	u_char		*buf;		/* Destination buffer (w) */
166 	size_t		bufsize;	/* size of provided buffer (r) */
167 	ife_type	rtype;		/* request type (r) */
168 	uint32_t	flags;		/* Request flags (r) */
169 	int		family;		/* Address family AF_* (r) */
170 	int		lladdr_off;	/* offset from header start (w) */
171 	int		lladdr_len;	/* lladdr length (r) */
172 	char		*lladdr;	/* link-level address pointer (r) */
173 	char		*hdata;		/* Upper layer header data (rw) */
174 };
175 
176 #define	IFENCAP_FLAG_BROADCAST	0x02	/* Destination is broadcast */
177 
178 /*
179  * Network interface send tag support. The storage of "struct
180  * m_snd_tag" comes from the network driver and it is free to allocate
181  * as much additional space as it wants for its own use.
182  */
183 struct m_snd_tag;
184 
185 #define	IF_SND_TAG_TYPE_RATE_LIMIT 0
186 #define	IF_SND_TAG_TYPE_MAX 1
187 
188 struct if_snd_tag_alloc_header {
189 	uint32_t type;		/* send tag type, see IF_SND_TAG_XXX */
190 	uint32_t flowid;	/* mbuf hash value */
191 	uint32_t flowtype;	/* mbuf hash type */
192 };
193 
194 struct if_snd_tag_alloc_rate_limit {
195 	struct if_snd_tag_alloc_header hdr;
196 	uint64_t max_rate;	/* in bytes/s */
197 };
198 
199 struct if_snd_tag_rate_limit_params {
200 	uint64_t max_rate;	/* in bytes/s */
201 };
202 
203 union if_snd_tag_alloc_params {
204 	struct if_snd_tag_alloc_header hdr;
205 	struct if_snd_tag_alloc_rate_limit rate_limit;
206 };
207 
208 union if_snd_tag_modify_params {
209 	struct if_snd_tag_rate_limit_params rate_limit;
210 };
211 
212 union if_snd_tag_query_params {
213 	struct if_snd_tag_rate_limit_params rate_limit;
214 };
215 
216 typedef int (if_snd_tag_alloc_t)(struct ifnet *, union if_snd_tag_alloc_params *,
217     struct m_snd_tag **);
218 typedef int (if_snd_tag_modify_t)(struct m_snd_tag *, union if_snd_tag_modify_params *);
219 typedef int (if_snd_tag_query_t)(struct m_snd_tag *, union if_snd_tag_query_params *);
220 typedef void (if_snd_tag_free_t)(struct m_snd_tag *);
221 
222 /*
223  * Structure defining a network interface.
224  */
225 struct ifnet {
226 	/* General book keeping of interface lists. */
227 	TAILQ_ENTRY(ifnet) if_link; 	/* all struct ifnets are chained */
228 	LIST_ENTRY(ifnet) if_clones;	/* interfaces of a cloner */
229 	TAILQ_HEAD(, ifg_list) if_groups; /* linked list of groups per if */
230 					/* protected by if_addr_lock */
231 	u_char	if_alloctype;		/* if_type at time of allocation */
232 
233 	/* Driver and protocol specific information that remains stable. */
234 	void	*if_softc;		/* pointer to driver state */
235 	void	*if_llsoftc;		/* link layer softc */
236 	void	*if_l2com;		/* pointer to protocol bits */
237 	const char *if_dname;		/* driver name */
238 	int	if_dunit;		/* unit or IF_DUNIT_NONE */
239 	u_short	if_index;		/* numeric abbreviation for this if  */
240 	short	if_index_reserved;	/* spare space to grow if_index */
241 	char	if_xname[IFNAMSIZ];	/* external name (name + unit) */
242 	char	*if_description;	/* interface description */
243 
244 	/* Variable fields that are touched by the stack and drivers. */
245 	int	if_flags;		/* up/down, broadcast, etc. */
246 	int	if_drv_flags;		/* driver-managed status flags */
247 	int	if_capabilities;	/* interface features & capabilities */
248 	int	if_capenable;		/* enabled features & capabilities */
249 	void	*if_linkmib;		/* link-type-specific MIB data */
250 	size_t	if_linkmiblen;		/* length of above data */
251 	u_int	if_refcount;		/* reference count */
252 
253 	/* These fields are shared with struct if_data. */
254 	uint8_t		if_type;	/* ethernet, tokenring, etc */
255 	uint8_t		if_addrlen;	/* media address length */
256 	uint8_t		if_hdrlen;	/* media header length */
257 	uint8_t		if_link_state;	/* current link state */
258 	uint32_t	if_mtu;		/* maximum transmission unit */
259 	uint32_t	if_metric;	/* routing metric (external only) */
260 	uint64_t	if_baudrate;	/* linespeed */
261 	uint64_t	if_hwassist;	/* HW offload capabilities, see IFCAP */
262 	time_t		if_epoch;	/* uptime at attach or stat reset */
263 	struct timeval	if_lastchange;	/* time of last administrative change */
264 
265 	struct  ifaltq if_snd;		/* output queue (includes altq) */
266 	struct	task if_linktask;	/* task for link change events */
267 
268 	/* Addresses of different protocol families assigned to this if. */
269 	struct	rwlock if_addr_lock;	/* lock to protect address lists */
270 		/*
271 		 * if_addrhead is the list of all addresses associated to
272 		 * an interface.
273 		 * Some code in the kernel assumes that first element
274 		 * of the list has type AF_LINK, and contains sockaddr_dl
275 		 * addresses which store the link-level address and the name
276 		 * of the interface.
277 		 * However, access to the AF_LINK address through this
278 		 * field is deprecated. Use if_addr or ifaddr_byindex() instead.
279 		 */
280 	struct	ifaddrhead if_addrhead;	/* linked list of addresses per if */
281 	struct	ifmultihead if_multiaddrs; /* multicast addresses configured */
282 	int	if_amcount;		/* number of all-multicast requests */
283 	struct	ifaddr	*if_addr;	/* pointer to link-level address */
284 	const u_int8_t *if_broadcastaddr; /* linklevel broadcast bytestring */
285 	struct	rwlock if_afdata_lock;
286 	void	*if_afdata[AF_MAX];
287 	int	if_afdata_initialized;
288 
289 	/* Additional features hung off the interface. */
290 	u_int	if_fib;			/* interface FIB */
291 	struct	vnet *if_vnet;		/* pointer to network stack instance */
292 	struct	vnet *if_home_vnet;	/* where this ifnet originates from */
293 	struct  ifvlantrunk *if_vlantrunk; /* pointer to 802.1q data */
294 	struct	bpf_if *if_bpf;		/* packet filter structure */
295 	int	if_pcount;		/* number of promiscuous listeners */
296 	void	*if_bridge;		/* bridge glue */
297 	void	*if_lagg;		/* lagg glue */
298 	void	*if_pf_kif;		/* pf glue */
299 	struct	carp_if *if_carp;	/* carp interface structure */
300 	struct	label *if_label;	/* interface MAC label */
301 	struct	netmap_adapter *if_netmap; /* netmap(4) softc */
302 
303 	/* Various procedures of the layer2 encapsulation and drivers. */
304 	int	(*if_output)		/* output routine (enqueue) */
305 		(struct ifnet *, struct mbuf *, const struct sockaddr *,
306 		     struct route *);
307 	void	(*if_input)		/* input routine (from h/w driver) */
308 		(struct ifnet *, struct mbuf *);
309 	if_start_fn_t	if_start;	/* initiate output routine */
310 	if_ioctl_fn_t	if_ioctl;	/* ioctl routine */
311 	if_init_fn_t	if_init;	/* Init routine */
312 	int	(*if_resolvemulti)	/* validate/resolve multicast */
313 		(struct ifnet *, struct sockaddr **, struct sockaddr *);
314 	if_qflush_fn_t	if_qflush;	/* flush any queue */
315 	if_transmit_fn_t if_transmit;   /* initiate output routine */
316 
317 	void	(*if_reassign)		/* reassign to vnet routine */
318 		(struct ifnet *, struct vnet *, char *);
319 	if_get_counter_t if_get_counter; /* get counter values */
320 	int	(*if_requestencap)	/* make link header from request */
321 		(struct ifnet *, struct if_encap_req *);
322 
323 	/* Statistics. */
324 	counter_u64_t	if_counters[IFCOUNTERS];
325 
326 	/* Stuff that's only temporary and doesn't belong here. */
327 
328 	/*
329 	 * Network adapter TSO limits:
330 	 * ===========================
331 	 *
332 	 * If the "if_hw_tsomax" field is zero the maximum segment
333 	 * length limit does not apply. If the "if_hw_tsomaxsegcount"
334 	 * or the "if_hw_tsomaxsegsize" field is zero the TSO segment
335 	 * count limit does not apply. If all three fields are zero,
336 	 * there is no TSO limit.
337 	 *
338 	 * NOTE: The TSO limits should reflect the values used in the
339 	 * BUSDMA tag a network adapter is using to load a mbuf chain
340 	 * for transmission. The TCP/IP network stack will subtract
341 	 * space for all linklevel and protocol level headers and
342 	 * ensure that the full mbuf chain passed to the network
343 	 * adapter fits within the given limits.
344 	 */
345 	u_int	if_hw_tsomax;		/* TSO maximum size in bytes */
346 	u_int	if_hw_tsomaxsegcount;	/* TSO maximum segment count */
347 	u_int	if_hw_tsomaxsegsize;	/* TSO maximum segment size in bytes */
348 
349 	/*
350 	 * Network adapter send tag support:
351 	 */
352 	if_snd_tag_alloc_t *if_snd_tag_alloc;
353 	if_snd_tag_modify_t *if_snd_tag_modify;
354 	if_snd_tag_query_t *if_snd_tag_query;
355 	if_snd_tag_free_t *if_snd_tag_free;
356 
357 	/*
358 	 * Spare fields to be added before branching a stable branch, so
359 	 * that structure can be enhanced without changing the kernel
360 	 * binary interface.
361 	 */
362 	int	if_ispare[4];		/* general use */
363 };
364 
365 /* for compatibility with other BSDs */
366 #define	if_name(ifp)	((ifp)->if_xname)
367 
368 /*
369  * Locks for address lists on the network interface.
370  */
371 #define	IF_ADDR_LOCK_INIT(if)	rw_init(&(if)->if_addr_lock, "if_addr_lock")
372 #define	IF_ADDR_LOCK_DESTROY(if)	rw_destroy(&(if)->if_addr_lock)
373 #define	IF_ADDR_WLOCK(if)	rw_wlock(&(if)->if_addr_lock)
374 #define	IF_ADDR_WUNLOCK(if)	rw_wunlock(&(if)->if_addr_lock)
375 #define	IF_ADDR_RLOCK(if)	rw_rlock(&(if)->if_addr_lock)
376 #define	IF_ADDR_RUNLOCK(if)	rw_runlock(&(if)->if_addr_lock)
377 #define	IF_ADDR_LOCK_ASSERT(if)	rw_assert(&(if)->if_addr_lock, RA_LOCKED)
378 #define	IF_ADDR_WLOCK_ASSERT(if) rw_assert(&(if)->if_addr_lock, RA_WLOCKED)
379 
380 /*
381  * Function variations on locking macros intended to be used by loadable
382  * kernel modules in order to divorce them from the internals of address list
383  * locking.
384  */
385 void	if_addr_rlock(struct ifnet *ifp);	/* if_addrhead */
386 void	if_addr_runlock(struct ifnet *ifp);	/* if_addrhead */
387 void	if_maddr_rlock(if_t ifp);	/* if_multiaddrs */
388 void	if_maddr_runlock(if_t ifp);	/* if_multiaddrs */
389 
390 #ifdef _KERNEL
391 #ifdef _SYS_EVENTHANDLER_H_
392 /* interface link layer address change event */
393 typedef void (*iflladdr_event_handler_t)(void *, struct ifnet *);
394 EVENTHANDLER_DECLARE(iflladdr_event, iflladdr_event_handler_t);
395 /* interface address change event */
396 typedef void (*ifaddr_event_handler_t)(void *, struct ifnet *);
397 EVENTHANDLER_DECLARE(ifaddr_event, ifaddr_event_handler_t);
398 /* new interface arrival event */
399 typedef void (*ifnet_arrival_event_handler_t)(void *, struct ifnet *);
400 EVENTHANDLER_DECLARE(ifnet_arrival_event, ifnet_arrival_event_handler_t);
401 /* interface departure event */
402 typedef void (*ifnet_departure_event_handler_t)(void *, struct ifnet *);
403 EVENTHANDLER_DECLARE(ifnet_departure_event, ifnet_departure_event_handler_t);
404 /* Interface link state change event */
405 typedef void (*ifnet_link_event_handler_t)(void *, struct ifnet *, int);
406 EVENTHANDLER_DECLARE(ifnet_link_event, ifnet_link_event_handler_t);
407 /* Interface up/down event */
408 #define IFNET_EVENT_UP		0
409 #define IFNET_EVENT_DOWN	1
410 typedef void (*ifnet_event_fn)(void *, struct ifnet *ifp, int event);
411 EVENTHANDLER_DECLARE(ifnet_event, ifnet_event_fn);
412 #endif /* _SYS_EVENTHANDLER_H_ */
413 
414 /*
415  * interface groups
416  */
417 struct ifg_group {
418 	char				 ifg_group[IFNAMSIZ];
419 	u_int				 ifg_refcnt;
420 	void				*ifg_pf_kif;
421 	TAILQ_HEAD(, ifg_member)	 ifg_members;
422 	TAILQ_ENTRY(ifg_group)		 ifg_next;
423 };
424 
425 struct ifg_member {
426 	TAILQ_ENTRY(ifg_member)	 ifgm_next;
427 	struct ifnet		*ifgm_ifp;
428 };
429 
430 struct ifg_list {
431 	struct ifg_group	*ifgl_group;
432 	TAILQ_ENTRY(ifg_list)	 ifgl_next;
433 };
434 
435 #ifdef _SYS_EVENTHANDLER_H_
436 /* group attach event */
437 typedef void (*group_attach_event_handler_t)(void *, struct ifg_group *);
438 EVENTHANDLER_DECLARE(group_attach_event, group_attach_event_handler_t);
439 /* group detach event */
440 typedef void (*group_detach_event_handler_t)(void *, struct ifg_group *);
441 EVENTHANDLER_DECLARE(group_detach_event, group_detach_event_handler_t);
442 /* group change event */
443 typedef void (*group_change_event_handler_t)(void *, const char *);
444 EVENTHANDLER_DECLARE(group_change_event, group_change_event_handler_t);
445 #endif /* _SYS_EVENTHANDLER_H_ */
446 
447 #define	IF_AFDATA_LOCK_INIT(ifp)	\
448 	rw_init(&(ifp)->if_afdata_lock, "if_afdata")
449 
450 #define	IF_AFDATA_WLOCK(ifp)	rw_wlock(&(ifp)->if_afdata_lock)
451 #define	IF_AFDATA_RLOCK(ifp)	rw_rlock(&(ifp)->if_afdata_lock)
452 #define	IF_AFDATA_WUNLOCK(ifp)	rw_wunlock(&(ifp)->if_afdata_lock)
453 #define	IF_AFDATA_RUNLOCK(ifp)	rw_runlock(&(ifp)->if_afdata_lock)
454 #define	IF_AFDATA_LOCK(ifp)	IF_AFDATA_WLOCK(ifp)
455 #define	IF_AFDATA_UNLOCK(ifp)	IF_AFDATA_WUNLOCK(ifp)
456 #define	IF_AFDATA_TRYLOCK(ifp)	rw_try_wlock(&(ifp)->if_afdata_lock)
457 #define	IF_AFDATA_DESTROY(ifp)	rw_destroy(&(ifp)->if_afdata_lock)
458 
459 #define	IF_AFDATA_LOCK_ASSERT(ifp)	rw_assert(&(ifp)->if_afdata_lock, RA_LOCKED)
460 #define	IF_AFDATA_RLOCK_ASSERT(ifp)	rw_assert(&(ifp)->if_afdata_lock, RA_RLOCKED)
461 #define	IF_AFDATA_WLOCK_ASSERT(ifp)	rw_assert(&(ifp)->if_afdata_lock, RA_WLOCKED)
462 #define	IF_AFDATA_UNLOCK_ASSERT(ifp)	rw_assert(&(ifp)->if_afdata_lock, RA_UNLOCKED)
463 
464 /*
465  * 72 was chosen below because it is the size of a TCP/IP
466  * header (40) + the minimum mss (32).
467  */
468 #define	IF_MINMTU	72
469 #define	IF_MAXMTU	65535
470 
471 #define	TOEDEV(ifp)	((ifp)->if_llsoftc)
472 
473 /*
474  * The ifaddr structure contains information about one address
475  * of an interface.  They are maintained by the different address families,
476  * are allocated and attached when an address is set, and are linked
477  * together so all addresses for an interface can be located.
478  *
479  * NOTE: a 'struct ifaddr' is always at the beginning of a larger
480  * chunk of malloc'ed memory, where we store the three addresses
481  * (ifa_addr, ifa_dstaddr and ifa_netmask) referenced here.
482  */
483 struct ifaddr {
484 	struct	sockaddr *ifa_addr;	/* address of interface */
485 	struct	sockaddr *ifa_dstaddr;	/* other end of p-to-p link */
486 #define	ifa_broadaddr	ifa_dstaddr	/* broadcast address interface */
487 	struct	sockaddr *ifa_netmask;	/* used to determine subnet */
488 	struct	ifnet *ifa_ifp;		/* back-pointer to interface */
489 	struct	carp_softc *ifa_carp;	/* pointer to CARP data */
490 	TAILQ_ENTRY(ifaddr) ifa_link;	/* queue macro glue */
491 	void	(*ifa_rtrequest)	/* check or clean routes (+ or -)'d */
492 		(int, struct rtentry *, struct rt_addrinfo *);
493 	u_short	ifa_flags;		/* mostly rt_flags for cloning */
494 #define	IFA_ROUTE	RTF_UP		/* route installed */
495 #define	IFA_RTSELF	RTF_HOST	/* loopback route to self installed */
496 	u_int	ifa_refcnt;		/* references to this structure */
497 
498 	counter_u64_t	ifa_ipackets;
499 	counter_u64_t	ifa_opackets;
500 	counter_u64_t	ifa_ibytes;
501 	counter_u64_t	ifa_obytes;
502 };
503 
504 struct ifaddr *	ifa_alloc(size_t size, int flags);
505 void	ifa_free(struct ifaddr *ifa);
506 void	ifa_ref(struct ifaddr *ifa);
507 
508 /*
509  * Multicast address structure.  This is analogous to the ifaddr
510  * structure except that it keeps track of multicast addresses.
511  */
512 struct ifmultiaddr {
513 	TAILQ_ENTRY(ifmultiaddr) ifma_link; /* queue macro glue */
514 	struct	sockaddr *ifma_addr; 	/* address this membership is for */
515 	struct	sockaddr *ifma_lladdr;	/* link-layer translation, if any */
516 	struct	ifnet *ifma_ifp;	/* back-pointer to interface */
517 	u_int	ifma_refcount;		/* reference count */
518 	void	*ifma_protospec;	/* protocol-specific state, if any */
519 	struct	ifmultiaddr *ifma_llifma; /* pointer to ifma for ifma_lladdr */
520 };
521 
522 extern	struct rwlock ifnet_rwlock;
523 extern	struct sx ifnet_sxlock;
524 
525 #define	IFNET_WLOCK() do {						\
526 	sx_xlock(&ifnet_sxlock);					\
527 	rw_wlock(&ifnet_rwlock);					\
528 } while (0)
529 
530 #define	IFNET_WUNLOCK() do {						\
531 	rw_wunlock(&ifnet_rwlock);					\
532 	sx_xunlock(&ifnet_sxlock);					\
533 } while (0)
534 
535 /*
536  * To assert the ifnet lock, you must know not only whether it's for read or
537  * write, but also whether it was acquired with sleep support or not.
538  */
539 #define	IFNET_RLOCK_ASSERT()		sx_assert(&ifnet_sxlock, SA_SLOCKED)
540 #define	IFNET_RLOCK_NOSLEEP_ASSERT()	rw_assert(&ifnet_rwlock, RA_RLOCKED)
541 #define	IFNET_WLOCK_ASSERT() do {					\
542 	sx_assert(&ifnet_sxlock, SA_XLOCKED);				\
543 	rw_assert(&ifnet_rwlock, RA_WLOCKED);				\
544 } while (0)
545 
546 #define	IFNET_RLOCK()		sx_slock(&ifnet_sxlock)
547 #define	IFNET_RLOCK_NOSLEEP()	rw_rlock(&ifnet_rwlock)
548 #define	IFNET_RUNLOCK()		sx_sunlock(&ifnet_sxlock)
549 #define	IFNET_RUNLOCK_NOSLEEP()	rw_runlock(&ifnet_rwlock)
550 
551 /*
552  * Look up an ifnet given its index; the _ref variant also acquires a
553  * reference that must be freed using if_rele().  It is almost always a bug
554  * to call ifnet_byindex() instead of ifnet_byindex_ref().
555  */
556 struct ifnet	*ifnet_byindex(u_short idx);
557 struct ifnet	*ifnet_byindex_locked(u_short idx);
558 struct ifnet	*ifnet_byindex_ref(u_short idx);
559 
560 /*
561  * Given the index, ifaddr_byindex() returns the one and only
562  * link-level ifaddr for the interface. You are not supposed to use
563  * it to traverse the list of addresses associated to the interface.
564  */
565 struct ifaddr	*ifaddr_byindex(u_short idx);
566 
567 VNET_DECLARE(struct ifnethead, ifnet);
568 VNET_DECLARE(struct ifgrouphead, ifg_head);
569 VNET_DECLARE(int, if_index);
570 VNET_DECLARE(struct ifnet *, loif);	/* first loopback interface */
571 
572 #define	V_ifnet		VNET(ifnet)
573 #define	V_ifg_head	VNET(ifg_head)
574 #define	V_if_index	VNET(if_index)
575 #define	V_loif		VNET(loif)
576 
577 int	if_addgroup(struct ifnet *, const char *);
578 int	if_delgroup(struct ifnet *, const char *);
579 int	if_addmulti(struct ifnet *, struct sockaddr *, struct ifmultiaddr **);
580 int	if_allmulti(struct ifnet *, int);
581 struct	ifnet* if_alloc(u_char);
582 void	if_attach(struct ifnet *);
583 void	if_dead(struct ifnet *);
584 int	if_delmulti(struct ifnet *, struct sockaddr *);
585 void	if_delmulti_ifma(struct ifmultiaddr *);
586 void	if_detach(struct ifnet *);
587 void	if_purgeaddrs(struct ifnet *);
588 void	if_delallmulti(struct ifnet *);
589 void	if_down(struct ifnet *);
590 struct ifmultiaddr *
591 	if_findmulti(struct ifnet *, const struct sockaddr *);
592 void	if_free(struct ifnet *);
593 void	if_initname(struct ifnet *, const char *, int);
594 void	if_link_state_change(struct ifnet *, int);
595 int	if_printf(struct ifnet *, const char *, ...) __printflike(2, 3);
596 void	if_ref(struct ifnet *);
597 void	if_rele(struct ifnet *);
598 int	if_setlladdr(struct ifnet *, const u_char *, int);
599 void	if_up(struct ifnet *);
600 int	ifioctl(struct socket *, u_long, caddr_t, struct thread *);
601 int	ifpromisc(struct ifnet *, int);
602 struct	ifnet *ifunit(const char *);
603 struct	ifnet *ifunit_ref(const char *);
604 
605 int	ifa_add_loopback_route(struct ifaddr *, struct sockaddr *);
606 int	ifa_del_loopback_route(struct ifaddr *, struct sockaddr *);
607 int	ifa_switch_loopback_route(struct ifaddr *, struct sockaddr *);
608 
609 struct	ifaddr *ifa_ifwithaddr(const struct sockaddr *);
610 int		ifa_ifwithaddr_check(const struct sockaddr *);
611 struct	ifaddr *ifa_ifwithbroadaddr(const struct sockaddr *, int);
612 struct	ifaddr *ifa_ifwithdstaddr(const struct sockaddr *, int);
613 struct	ifaddr *ifa_ifwithnet(const struct sockaddr *, int, int);
614 struct	ifaddr *ifa_ifwithroute(int, const struct sockaddr *, struct sockaddr *,
615     u_int);
616 struct	ifaddr *ifaof_ifpforaddr(const struct sockaddr *, struct ifnet *);
617 int	ifa_preferred(struct ifaddr *, struct ifaddr *);
618 
619 int	if_simloop(struct ifnet *ifp, struct mbuf *m, int af, int hlen);
620 
621 typedef	void *if_com_alloc_t(u_char type, struct ifnet *ifp);
622 typedef	void if_com_free_t(void *com, u_char type);
623 void	if_register_com_alloc(u_char type, if_com_alloc_t *a, if_com_free_t *f);
624 void	if_deregister_com_alloc(u_char type);
625 void	if_data_copy(struct ifnet *, struct if_data *);
626 uint64_t if_get_counter_default(struct ifnet *, ift_counter);
627 void	if_inc_counter(struct ifnet *, ift_counter, int64_t);
628 
629 #define IF_LLADDR(ifp)							\
630     LLADDR((struct sockaddr_dl *)((ifp)->if_addr->ifa_addr))
631 
632 uint64_t if_setbaudrate(if_t ifp, uint64_t baudrate);
633 uint64_t if_getbaudrate(if_t ifp);
634 int if_setcapabilities(if_t ifp, int capabilities);
635 int if_setcapabilitiesbit(if_t ifp, int setbit, int clearbit);
636 int if_getcapabilities(if_t ifp);
637 int if_togglecapenable(if_t ifp, int togglecap);
638 int if_setcapenable(if_t ifp, int capenable);
639 int if_setcapenablebit(if_t ifp, int setcap, int clearcap);
640 int if_getcapenable(if_t ifp);
641 const char *if_getdname(if_t ifp);
642 int if_setdev(if_t ifp, void *dev);
643 int if_setdrvflagbits(if_t ifp, int if_setflags, int clear_flags);
644 int if_getdrvflags(if_t ifp);
645 int if_setdrvflags(if_t ifp, int flags);
646 int if_clearhwassist(if_t ifp);
647 int if_sethwassistbits(if_t ifp, int toset, int toclear);
648 int if_sethwassist(if_t ifp, int hwassist_bit);
649 int if_gethwassist(if_t ifp);
650 int if_setsoftc(if_t ifp, void *softc);
651 void *if_getsoftc(if_t ifp);
652 int if_setflags(if_t ifp, int flags);
653 int if_setmtu(if_t ifp, int mtu);
654 int if_getmtu(if_t ifp);
655 int if_getmtu_family(if_t ifp, int family);
656 int if_setflagbits(if_t ifp, int set, int clear);
657 int if_getflags(if_t ifp);
658 int if_sendq_empty(if_t ifp);
659 int if_setsendqready(if_t ifp);
660 int if_setsendqlen(if_t ifp, int tx_desc_count);
661 int if_sethwtsomax(if_t ifp, u_int if_hw_tsomax);
662 int if_sethwtsomaxsegcount(if_t ifp, u_int if_hw_tsomaxsegcount);
663 int if_sethwtsomaxsegsize(if_t ifp, u_int if_hw_tsomaxsegsize);
664 u_int if_gethwtsomax(if_t ifp);
665 u_int if_gethwtsomaxsegcount(if_t ifp);
666 u_int if_gethwtsomaxsegsize(if_t ifp);
667 int if_input(if_t ifp, struct mbuf* sendmp);
668 int if_sendq_prepend(if_t ifp, struct mbuf *m);
669 struct mbuf *if_dequeue(if_t ifp);
670 int if_setifheaderlen(if_t ifp, int len);
671 void if_setrcvif(struct mbuf *m, if_t ifp);
672 void if_setvtag(struct mbuf *m, u_int16_t tag);
673 u_int16_t if_getvtag(struct mbuf *m);
674 int if_vlantrunkinuse(if_t ifp);
675 caddr_t if_getlladdr(if_t ifp);
676 void *if_gethandle(u_char);
677 void if_bpfmtap(if_t ifp, struct mbuf *m);
678 void if_etherbpfmtap(if_t ifp, struct mbuf *m);
679 void if_vlancap(if_t ifp);
680 
681 int if_setupmultiaddr(if_t ifp, void *mta, int *cnt, int max);
682 int if_multiaddr_array(if_t ifp, void *mta, int *cnt, int max);
683 int if_multiaddr_count(if_t ifp, int max);
684 
685 int if_multi_apply(struct ifnet *ifp, int (*filter)(void *, struct ifmultiaddr *, int), void *arg);
686 int if_getamcount(if_t ifp);
687 struct ifaddr * if_getifaddr(if_t ifp);
688 
689 /* Functions */
690 void if_setinitfn(if_t ifp, void (*)(void *));
691 void if_setioctlfn(if_t ifp, int (*)(if_t, u_long, caddr_t));
692 void if_setstartfn(if_t ifp, void (*)(if_t));
693 void if_settransmitfn(if_t ifp, if_transmit_fn_t);
694 void if_setqflushfn(if_t ifp, if_qflush_fn_t);
695 void if_setgetcounterfn(if_t ifp, if_get_counter_t);
696 
697 /* Revisit the below. These are inline functions originally */
698 int drbr_inuse_drv(if_t ifp, struct buf_ring *br);
699 struct mbuf* drbr_dequeue_drv(if_t ifp, struct buf_ring *br);
700 int drbr_needs_enqueue_drv(if_t ifp, struct buf_ring *br);
701 int drbr_enqueue_drv(if_t ifp, struct buf_ring *br, struct mbuf *m);
702 
703 /* TSO */
704 void if_hw_tsomax_common(if_t ifp, struct ifnet_hw_tsomax *);
705 int if_hw_tsomax_update(if_t ifp, struct ifnet_hw_tsomax *);
706 
707 #ifdef DEVICE_POLLING
708 enum poll_cmd { POLL_ONLY, POLL_AND_CHECK_STATUS };
709 
710 typedef	int poll_handler_t(if_t ifp, enum poll_cmd cmd, int count);
711 int    ether_poll_register(poll_handler_t *h, if_t ifp);
712 int    ether_poll_deregister(if_t ifp);
713 #endif /* DEVICE_POLLING */
714 
715 #endif /* _KERNEL */
716 
717 #include <net/ifq.h>	/* XXXAO: temporary unconditional include */
718 
719 #endif /* !_NET_IF_VAR_H_ */
720