xref: /freebsd/sys/net/if_var.h (revision 7773002178c8dbc52b44e4d705f07706409af8e4)
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. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  *	From: @(#)if.h	8.1 (Berkeley) 6/10/93
34  * $FreeBSD$
35  */
36 
37 #ifndef	_NET_IF_VAR_H_
38 #define	_NET_IF_VAR_H_
39 
40 /*
41  * Structures defining a network interface, providing a packet
42  * transport mechanism (ala level 0 of the PUP protocols).
43  *
44  * Each interface accepts output datagrams of a specified maximum
45  * length, and provides higher level routines with input datagrams
46  * received from its medium.
47  *
48  * Output occurs when the routine if_output is called, with three parameters:
49  *	(*ifp->if_output)(ifp, m, dst, rt)
50  * Here m is the mbuf chain to be sent and dst is the destination address.
51  * The output routine encapsulates the supplied datagram if necessary,
52  * and then transmits it on its medium.
53  *
54  * On input, each interface unwraps the data received by it, and either
55  * places it on the input queue of an internetwork datagram routine
56  * and posts the associated software interrupt, or passes the datagram to a raw
57  * packet input routine.
58  *
59  * Routines exist for locating interfaces by their addresses
60  * or for locating an interface on a certain network, as well as more general
61  * routing and gateway routines maintaining information used to locate
62  * interfaces.  These routines live in the files if.c and route.c
63  */
64 
65 #ifdef __STDC__
66 /*
67  * Forward structure declarations for function prototypes [sic].
68  */
69 struct	mbuf;
70 struct	thread;
71 struct	rtentry;
72 struct	rt_addrinfo;
73 struct	socket;
74 struct	ether_header;
75 #endif
76 
77 #include <sys/_label.h>		/* struct label */
78 #include <sys/queue.h>		/* get TAILQ macros */
79 
80 #ifdef _KERNEL
81 #include <sys/mbuf.h>
82 #endif /* _KERNEL */
83 #include <sys/lock.h>		/* XXX */
84 #include <sys/mutex.h>		/* XXX */
85 #include <sys/event.h>		/* XXX */
86 
87 #define	IF_DUNIT_NONE	-1
88 
89 TAILQ_HEAD(ifnethead, ifnet);	/* we use TAILQs so that the order of */
90 TAILQ_HEAD(ifaddrhead, ifaddr);	/* instantiation is preserved in the list */
91 TAILQ_HEAD(ifprefixhead, ifprefix);
92 TAILQ_HEAD(ifmultihead, ifmultiaddr);
93 
94 /*
95  * Structure defining a queue for a network interface.
96  */
97 struct	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  */
131 struct 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 	struct	klist if_klist;		/* events attached to this if */
139 	int	if_pcount;		/* number of promiscuous listeners */
140 	struct	bpf_if *if_bpf;		/* packet filter structure */
141 	u_short	if_index;		/* numeric abbreviation for this if  */
142 	short	if_timer;		/* time 'til if_watchdog called */
143 	u_short	if_nvlans;		/* number of active vlans */
144 	int	if_flags;		/* up/down, broadcast, etc. */
145 	int	if_capabilities;	/* interface capabilities */
146 	int	if_capenable;		/* enabled features */
147 	int	if_ipending;		/* interrupts pending */
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 rtentry *);
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_done)		/* output complete routine */
162 		(struct ifnet *);	/* (XXX not used; fake prototype) */
163 	int	(*if_ioctl)		/* ioctl routine */
164 		(struct ifnet *, u_long, caddr_t);
165 	void	(*if_watchdog)		/* timer routine */
166 		(struct ifnet *);
167 	int	(*if_poll_recv)		/* polled receive routine */
168 		(struct ifnet *, int *);
169 	int	(*if_poll_xmit)		/* polled transmit routine */
170 		(struct ifnet *, int *);
171 	void	(*if_poll_intren)	/* polled interrupt reenable routine */
172 		(struct ifnet *);
173 	void	(*if_poll_slowinput)	/* input routine for slow devices */
174 		(struct ifnet *, struct mbuf *);
175 	void	(*if_init)		/* Init routine */
176 		(void *);
177 	int	(*if_resolvemulti)	/* validate/resolve multicast */
178 		(struct ifnet *, struct sockaddr **, struct sockaddr *);
179 	struct	ifqueue if_snd;		/* output queue */
180 	struct	ifqueue *if_poll_slowq;	/* input queue for slow devices */
181 	struct	ifprefixhead if_prefixhead; /* list of prefixes per if */
182 	u_int8_t *if_broadcastaddr;	/* linklevel broadcast bytestring */
183 	struct	label if_label;		/* interface MAC label */
184 
185 	void	*if_afdata[AF_MAX];
186 	int	if_afdata_initialized;
187 	struct	mtx if_afdata_mtx;
188 };
189 
190 typedef void if_init_f_t(void *);
191 
192 #define	if_mtu		if_data.ifi_mtu
193 #define	if_type		if_data.ifi_type
194 #define if_physical	if_data.ifi_physical
195 #define	if_addrlen	if_data.ifi_addrlen
196 #define	if_hdrlen	if_data.ifi_hdrlen
197 #define	if_metric	if_data.ifi_metric
198 #define	if_baudrate	if_data.ifi_baudrate
199 #define	if_hwassist	if_data.ifi_hwassist
200 #define	if_ipackets	if_data.ifi_ipackets
201 #define	if_ierrors	if_data.ifi_ierrors
202 #define	if_opackets	if_data.ifi_opackets
203 #define	if_oerrors	if_data.ifi_oerrors
204 #define	if_collisions	if_data.ifi_collisions
205 #define	if_ibytes	if_data.ifi_ibytes
206 #define	if_obytes	if_data.ifi_obytes
207 #define	if_imcasts	if_data.ifi_imcasts
208 #define	if_omcasts	if_data.ifi_omcasts
209 #define	if_iqdrops	if_data.ifi_iqdrops
210 #define	if_noproto	if_data.ifi_noproto
211 #define	if_lastchange	if_data.ifi_lastchange
212 #define if_recvquota	if_data.ifi_recvquota
213 #define	if_xmitquota	if_data.ifi_xmitquota
214 #define if_rawoutput(if, m, sa) if_output(if, m, sa, (struct rtentry *)0)
215 
216 /* for compatibility with other BSDs */
217 #define	if_addrlist	if_addrhead
218 #define	if_list		if_link
219 
220 /*
221  * Bit values in if_ipending
222  */
223 #define	IFI_RECV	1	/* I want to receive */
224 #define	IFI_XMIT	2	/* I want to transmit */
225 
226 /*
227  * Output queues (ifp->if_snd) and slow device input queues (*ifp->if_slowq)
228  * are queues of messages stored on ifqueue structures
229  * (defined above).  Entries are added to and deleted from these structures
230  * by these macros, which should be called with ipl raised to splimp().
231  */
232 #define IF_LOCK(ifq)		mtx_lock(&(ifq)->ifq_mtx)
233 #define IF_UNLOCK(ifq)		mtx_unlock(&(ifq)->ifq_mtx)
234 #define	_IF_QFULL(ifq)		((ifq)->ifq_len >= (ifq)->ifq_maxlen)
235 #define	_IF_DROP(ifq)		((ifq)->ifq_drops++)
236 #define	_IF_QLEN(ifq)		((ifq)->ifq_len)
237 
238 #define	_IF_ENQUEUE(ifq, m) do { 				\
239 	(m)->m_nextpkt = NULL;					\
240 	if ((ifq)->ifq_tail == NULL) 				\
241 		(ifq)->ifq_head = m; 				\
242 	else 							\
243 		(ifq)->ifq_tail->m_nextpkt = m; 		\
244 	(ifq)->ifq_tail = m; 					\
245 	(ifq)->ifq_len++; 					\
246 } while (0)
247 
248 #define IF_ENQUEUE(ifq, m) do {					\
249 	IF_LOCK(ifq); 						\
250 	_IF_ENQUEUE(ifq, m); 					\
251 	IF_UNLOCK(ifq); 					\
252 } while (0)
253 
254 #define	_IF_PREPEND(ifq, m) do {				\
255 	(m)->m_nextpkt = (ifq)->ifq_head; 			\
256 	if ((ifq)->ifq_tail == NULL) 				\
257 		(ifq)->ifq_tail = (m); 				\
258 	(ifq)->ifq_head = (m); 					\
259 	(ifq)->ifq_len++; 					\
260 } while (0)
261 
262 #define IF_PREPEND(ifq, m) do {		 			\
263 	IF_LOCK(ifq); 						\
264 	_IF_PREPEND(ifq, m); 					\
265 	IF_UNLOCK(ifq); 					\
266 } while (0)
267 
268 #define	_IF_DEQUEUE(ifq, m) do { 				\
269 	(m) = (ifq)->ifq_head; 					\
270 	if (m) { 						\
271 		if (((ifq)->ifq_head = (m)->m_nextpkt) == 0) 	\
272 			(ifq)->ifq_tail = NULL; 		\
273 		(m)->m_nextpkt = NULL; 				\
274 		(ifq)->ifq_len--; 				\
275 	} 							\
276 } while (0)
277 
278 #define IF_DEQUEUE(ifq, m) do { 				\
279 	IF_LOCK(ifq); 						\
280 	_IF_DEQUEUE(ifq, m); 					\
281 	IF_UNLOCK(ifq); 					\
282 } while (0)
283 
284 #define IF_DRAIN(ifq) do { 					\
285 	struct mbuf *m; 					\
286 	IF_LOCK(ifq); 						\
287 	for (;;) { 						\
288 		_IF_DEQUEUE(ifq, m); 				\
289 		if (m == NULL) 					\
290 			break; 					\
291 		m_freem(m); 					\
292 	} 							\
293 	IF_UNLOCK(ifq); 					\
294 } while (0)
295 
296 #ifdef _KERNEL
297 #define	IF_AFDATA_LOCK_INIT(ifp)	\
298     mtx_init(&(ifp)->if_afdata_mtx, "if_afdata", NULL, MTX_DEF)
299 #define	IF_AFDATA_LOCK(ifp)	mtx_lock(&(ifp)->if_afdata_mtx)
300 #define	IF_AFDATA_TRYLOCK(ifp)	mtx_trylock(&(ifp)->if_afdata_mtx)
301 #define	IF_AFDATA_UNLOCK(ifp)	mtx_unlock(&(ifp)->if_afdata_mtx)
302 #define	IF_AFDATA_DESTROY(ifp)	mtx_destroy(&(ifp)->if_afdata_mtx)
303 
304 #define	IF_HANDOFF(ifq, m, ifp)			if_handoff(ifq, m, ifp, 0)
305 #define	IF_HANDOFF_ADJ(ifq, m, ifp, adj)	if_handoff(ifq, m, ifp, adj)
306 
307 static __inline int
308 if_handoff(struct ifqueue *ifq, struct mbuf *m, struct ifnet *ifp, int adjust)
309 {
310 	int active = 0;
311 
312 	IF_LOCK(ifq);
313 	if (_IF_QFULL(ifq)) {
314 		_IF_DROP(ifq);
315 		IF_UNLOCK(ifq);
316 		m_freem(m);
317 		return (0);
318 	}
319 	if (ifp != NULL) {
320 		ifp->if_obytes += m->m_pkthdr.len + adjust;
321 		if (m->m_flags & M_MCAST)
322 			ifp->if_omcasts++;
323 		active = ifp->if_flags & IFF_OACTIVE;
324 	}
325 	_IF_ENQUEUE(ifq, m);
326 	IF_UNLOCK(ifq);
327 	if (ifp != NULL && !active)
328 		(*ifp->if_start)(ifp);
329 	return (1);
330 }
331 
332 /*
333  * 72 was chosen below because it is the size of a TCP/IP
334  * header (40) + the minimum mss (32).
335  */
336 #define	IF_MINMTU	72
337 #define	IF_MAXMTU	65535
338 
339 #endif /* _KERNEL */
340 
341 /*
342  * The ifaddr structure contains information about one address
343  * of an interface.  They are maintained by the different address families,
344  * are allocated and attached when an address is set, and are linked
345  * together so all addresses for an interface can be located.
346  */
347 struct ifaddr {
348 	struct	sockaddr *ifa_addr;	/* address of interface */
349 	struct	sockaddr *ifa_dstaddr;	/* other end of p-to-p link */
350 #define	ifa_broadaddr	ifa_dstaddr	/* broadcast address interface */
351 	struct	sockaddr *ifa_netmask;	/* used to determine subnet */
352 	struct	if_data if_data;	/* not all members are meaningful */
353 	struct	ifnet *ifa_ifp;		/* back-pointer to interface */
354 	TAILQ_ENTRY(ifaddr) ifa_link;	/* queue macro glue */
355 	void	(*ifa_rtrequest)	/* check or clean routes (+ or -)'d */
356 		(int, struct rtentry *, struct rt_addrinfo *);
357 	u_short	ifa_flags;		/* mostly rt_flags for cloning */
358 	u_int	ifa_refcnt;		/* references to this structure */
359 	int	ifa_metric;		/* cost of going out this interface */
360 #ifdef notdef
361 	struct	rtentry *ifa_rt;	/* XXXX for ROUTETOIF ????? */
362 #endif
363 	int (*ifa_claim_addr)		/* check if an addr goes to this if */
364 		(struct ifaddr *, struct sockaddr *);
365 	struct mtx ifa_mtx;
366 };
367 #define	IFA_ROUTE	RTF_UP		/* route installed */
368 
369 /* for compatibility with other BSDs */
370 #define	ifa_list	ifa_link
371 
372 #define	IFA_LOCK_INIT(ifa)	\
373     mtx_init(&(ifa)->ifa_mtx, "ifaddr", NULL, MTX_DEF)
374 #define	IFA_LOCK(ifa)		mtx_lock(&(ifa)->ifa_mtx)
375 #define	IFA_UNLOCK(ifa)		mtx_unlock(&(ifa)->ifa_mtx)
376 #define	IFA_DESTROY(ifa)	mtx_destroy(&(ifa)->ifa_mtx)
377 
378 /*
379  * The prefix structure contains information about one prefix
380  * of an interface.  They are maintained by the different address families,
381  * are allocated and attached when a prefix or an address is set,
382  * and are linked together so all prefixes for an interface can be located.
383  */
384 struct ifprefix {
385 	struct	sockaddr *ifpr_prefix;	/* prefix of interface */
386 	struct	ifnet *ifpr_ifp;	/* back-pointer to interface */
387 	TAILQ_ENTRY(ifprefix) ifpr_list; /* queue macro glue */
388 	u_char	ifpr_plen;		/* prefix length in bits */
389 	u_char	ifpr_type;		/* protocol dependent prefix type */
390 };
391 
392 /*
393  * Multicast address structure.  This is analogous to the ifaddr
394  * structure except that it keeps track of multicast addresses.
395  * Also, the reference count here is a count of requests for this
396  * address, not a count of pointers to this structure.
397  */
398 struct ifmultiaddr {
399 	TAILQ_ENTRY(ifmultiaddr) ifma_link; /* queue macro glue */
400 	struct	sockaddr *ifma_addr; 	/* address this membership is for */
401 	struct	sockaddr *ifma_lladdr;	/* link-layer translation, if any */
402 	struct	ifnet *ifma_ifp;	/* back-pointer to interface */
403 	u_int	ifma_refcount;		/* reference count */
404 	void	*ifma_protospec;	/* protocol-specific state, if any */
405 };
406 
407 #ifdef _KERNEL
408 #define	IFAFREE(ifa)					\
409 	do {						\
410 		IFA_LOCK(ifa);				\
411 		KASSERT((ifa)->ifa_refcnt > 0,		\
412 		    ("ifa %p !(ifa_refcnt > 0)", ifa));	\
413 		if (--(ifa)->ifa_refcnt == 0) {		\
414 			IFA_DESTROY(ifa);		\
415 			free(ifa, M_IFADDR);		\
416 		} else 					\
417 			IFA_UNLOCK(ifa);		\
418 	} while (0)
419 
420 #define IFAREF(ifa)					\
421 	do {						\
422 		IFA_LOCK(ifa);				\
423 		++(ifa)->ifa_refcnt;			\
424 		IFA_UNLOCK(ifa);			\
425 	} while (0)
426 
427 extern	struct mtx ifnet_lock;
428 #define	IFNET_LOCK_INIT() \
429     mtx_init(&ifnet_lock, "ifnet", NULL, MTX_DEF | MTX_RECURSE)
430 #define	IFNET_WLOCK()		mtx_lock(&ifnet_lock)
431 #define	IFNET_WUNLOCK()		mtx_unlock(&ifnet_lock)
432 #define	IFNET_RLOCK()		IFNET_WLOCK()
433 #define	IFNET_RUNLOCK()		IFNET_WUNLOCK()
434 
435 struct ifindex_entry {
436 	struct	ifnet *ife_ifnet;
437 	struct	ifaddr *ife_ifnet_addr;
438 	dev_t	ife_dev;
439 };
440 
441 #define ifnet_byindex(idx)	ifindex_table[(idx)].ife_ifnet
442 #define ifaddr_byindex(idx)	ifindex_table[(idx)].ife_ifnet_addr
443 #define ifdev_byindex(idx)	ifindex_table[(idx)].ife_dev
444 
445 extern	struct ifnethead ifnet;
446 extern	struct ifindex_entry *ifindex_table;
447 extern	int ifqmaxlen;
448 extern	struct ifnet *loif;	/* first loopback interface */
449 extern	int if_index;
450 
451 int	if_addmulti(struct ifnet *, struct sockaddr *, struct ifmultiaddr **);
452 int	if_allmulti(struct ifnet *, int);
453 void	if_attach(struct ifnet *);
454 int	if_delmulti(struct ifnet *, struct sockaddr *);
455 void	if_detach(struct ifnet *);
456 void	if_down(struct ifnet *);
457 void	if_initname(struct ifnet *, const char *, int);
458 int	if_printf(struct ifnet *, const char *, ...) __printflike(2, 3);
459 void	if_route(struct ifnet *, int flag, int fam);
460 int	if_setlladdr(struct ifnet *, const u_char *, int);
461 void	if_unroute(struct ifnet *, int flag, int fam);
462 void	if_up(struct ifnet *);
463 /*void	ifinit(void);*/ /* declared in systm.h for main() */
464 int	ifioctl(struct socket *, u_long, caddr_t, struct thread *);
465 int	ifpromisc(struct ifnet *, int);
466 struct	ifnet *ifunit(const char *);
467 struct	ifnet *if_withname(struct sockaddr *);
468 
469 int	if_poll_recv_slow(struct ifnet *ifp, int *quotap);
470 void	if_poll_xmit_slow(struct ifnet *ifp, int *quotap);
471 void	if_poll_throttle(void);
472 void	if_poll_unthrottle(void *);
473 void	if_poll_init(void);
474 void	if_poll(void);
475 
476 struct	ifaddr *ifa_ifwithaddr(struct sockaddr *);
477 struct	ifaddr *ifa_ifwithdstaddr(struct sockaddr *);
478 struct	ifaddr *ifa_ifwithnet(struct sockaddr *);
479 struct	ifaddr *ifa_ifwithroute(int, struct sockaddr *, struct sockaddr *);
480 struct	ifaddr *ifaof_ifpforaddr(struct sockaddr *, struct ifnet *);
481 
482 struct	ifmultiaddr *ifmaof_ifpforaddr(struct sockaddr *, struct ifnet *);
483 int	if_simloop(struct ifnet *ifp, struct mbuf *m, int af, int hlen);
484 
485 void	if_clone_attach(struct if_clone *);
486 void	if_clone_detach(struct if_clone *);
487 
488 int	if_clone_create(char *, int);
489 int	if_clone_destroy(const char *);
490 
491 #define IF_LLADDR(ifp)							\
492     LLADDR((struct sockaddr_dl *) ifaddr_byindex((ifp)->if_index)->ifa_addr)
493 
494 #ifdef DEVICE_POLLING
495 enum poll_cmd {	POLL_ONLY, POLL_AND_CHECK_STATUS, POLL_DEREGISTER };
496 
497 typedef	void poll_handler_t(struct ifnet *ifp, enum poll_cmd cmd, int count);
498 int    ether_poll_register(poll_handler_t *h, struct ifnet *ifp);
499 int    ether_poll_deregister(struct ifnet *ifp);
500 #endif /* DEVICE_POLLING */
501 
502 #endif /* _KERNEL */
503 
504 #endif /* !_NET_IF_VAR_H_ */
505