xref: /freebsd/sys/net/if_var.h (revision 4b2eaea43fec8e8792be611dea204071a10b655a)
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 TAILQ_HEAD(ifnethead, ifnet);	/* we use TAILQs so that the order of */
88 TAILQ_HEAD(ifaddrhead, ifaddr);	/* instantiation is preserved in the list */
89 TAILQ_HEAD(ifprefixhead, ifprefix);
90 TAILQ_HEAD(ifmultihead, ifmultiaddr);
91 
92 /*
93  * Structure defining a queue for a network interface.
94  */
95 struct	ifqueue {
96 	struct	mbuf *ifq_head;
97 	struct	mbuf *ifq_tail;
98 	int	ifq_len;
99 	int	ifq_maxlen;
100 	int	ifq_drops;
101 	struct	mtx ifq_mtx;
102 };
103 
104 /*
105  * Structure defining a network interface.
106  *
107  * (Would like to call this struct ``if'', but C isn't PL/1.)
108  */
109 
110 /*
111  * NB: For FreeBSD, it is assumed that each NIC driver's softc starts with
112  * one of these structures, typically held within an arpcom structure.
113  *
114  *	struct <foo>_softc {
115  *		struct arpcom {
116  *			struct  ifnet ac_if;
117  *			...
118  *		} <arpcom> ;
119  *		...
120  *	};
121  *
122  * The assumption is used in a number of places, including many
123  * files in sys/net, device drivers, and sys/dev/mii.c:miibus_attach().
124  *
125  * Unfortunately devices' softc are opaque, so we depend on this layout
126  * to locate the struct ifnet from the softc in the generic code.
127  *
128  */
129 struct ifnet {
130 	void	*if_softc;		/* pointer to driver state */
131 	char	*if_name;		/* name, e.g. ``en'' or ``lo'' */
132 	TAILQ_ENTRY(ifnet) if_link; 	/* all struct ifnets are chained */
133 	struct	ifaddrhead if_addrhead;	/* linked list of addresses per if */
134 	struct	klist if_klist;		/* events attached to this if */
135 	int	if_pcount;		/* number of promiscuous listeners */
136 	struct	bpf_if *if_bpf;		/* packet filter structure */
137 	u_short	if_index;		/* numeric abbreviation for this if  */
138 	short	if_unit;		/* sub-unit for lower level driver */
139 	short	if_timer;		/* time 'til if_watchdog called */
140 	u_short	if_nvlans;		/* number of active vlans */
141 	int	if_flags;		/* up/down, broadcast, etc. */
142 	int	if_capabilities;	/* interface capabilities */
143 	int	if_capenable;		/* enabled features */
144 	int	if_ipending;		/* interrupts pending */
145 	void	*if_linkmib;		/* link-type-specific MIB data */
146 	size_t	if_linkmiblen;		/* length of above data */
147 	struct	if_data if_data;
148 	struct	ifmultihead if_multiaddrs; /* multicast addresses configured */
149 	int	if_amcount;		/* number of all-multicast requests */
150 /* procedure handles */
151 	int	(*if_output)		/* output routine (enqueue) */
152 		(struct ifnet *, struct mbuf *, struct sockaddr *,
153 		     struct rtentry *);
154 	void	(*if_input)		/* input routine (from h/w driver) */
155 		(struct ifnet *, struct mbuf *);
156 	void	(*if_start)		/* initiate output routine */
157 		(struct ifnet *);
158 	int	(*if_done)		/* output complete routine */
159 		(struct ifnet *);	/* (XXX not used; fake prototype) */
160 	int	(*if_ioctl)		/* ioctl routine */
161 		(struct ifnet *, u_long, caddr_t);
162 	void	(*if_watchdog)		/* timer routine */
163 		(struct ifnet *);
164 	int	(*if_poll_recv)		/* polled receive routine */
165 		(struct ifnet *, int *);
166 	int	(*if_poll_xmit)		/* polled transmit routine */
167 		(struct ifnet *, int *);
168 	void	(*if_poll_intren)	/* polled interrupt reenable routine */
169 		(struct ifnet *);
170 	void	(*if_poll_slowinput)	/* input routine for slow devices */
171 		(struct ifnet *, struct mbuf *);
172 	void	(*if_init)		/* Init routine */
173 		(void *);
174 	int	(*if_resolvemulti)	/* validate/resolve multicast */
175 		(struct ifnet *, struct sockaddr **, struct sockaddr *);
176 	struct	ifqueue if_snd;		/* output queue */
177 	struct	ifqueue *if_poll_slowq;	/* input queue for slow devices */
178 	struct	ifprefixhead if_prefixhead; /* list of prefixes per if */
179 	u_int8_t *if_broadcastaddr;	/* linklevel broadcast bytestring */
180 	struct	label if_label;		/* interface MAC label */
181 };
182 
183 typedef void if_init_f_t(void *);
184 
185 #define	if_mtu		if_data.ifi_mtu
186 #define	if_type		if_data.ifi_type
187 #define if_physical	if_data.ifi_physical
188 #define	if_addrlen	if_data.ifi_addrlen
189 #define	if_hdrlen	if_data.ifi_hdrlen
190 #define	if_metric	if_data.ifi_metric
191 #define	if_baudrate	if_data.ifi_baudrate
192 #define	if_hwassist	if_data.ifi_hwassist
193 #define	if_ipackets	if_data.ifi_ipackets
194 #define	if_ierrors	if_data.ifi_ierrors
195 #define	if_opackets	if_data.ifi_opackets
196 #define	if_oerrors	if_data.ifi_oerrors
197 #define	if_collisions	if_data.ifi_collisions
198 #define	if_ibytes	if_data.ifi_ibytes
199 #define	if_obytes	if_data.ifi_obytes
200 #define	if_imcasts	if_data.ifi_imcasts
201 #define	if_omcasts	if_data.ifi_omcasts
202 #define	if_iqdrops	if_data.ifi_iqdrops
203 #define	if_noproto	if_data.ifi_noproto
204 #define	if_lastchange	if_data.ifi_lastchange
205 #define if_recvquota	if_data.ifi_recvquota
206 #define	if_xmitquota	if_data.ifi_xmitquota
207 #define if_rawoutput(if, m, sa) if_output(if, m, sa, (struct rtentry *)0)
208 
209 /* for compatibility with other BSDs */
210 #define	if_addrlist	if_addrhead
211 #define	if_list		if_link
212 
213 /*
214  * Bit values in if_ipending
215  */
216 #define	IFI_RECV	1	/* I want to receive */
217 #define	IFI_XMIT	2	/* I want to transmit */
218 
219 /*
220  * Output queues (ifp->if_snd) and slow device input queues (*ifp->if_slowq)
221  * are queues of messages stored on ifqueue structures
222  * (defined above).  Entries are added to and deleted from these structures
223  * by these macros, which should be called with ipl raised to splimp().
224  */
225 #define IF_LOCK(ifq)		mtx_lock(&(ifq)->ifq_mtx)
226 #define IF_UNLOCK(ifq)		mtx_unlock(&(ifq)->ifq_mtx)
227 #define	_IF_QFULL(ifq)		((ifq)->ifq_len >= (ifq)->ifq_maxlen)
228 #define	_IF_DROP(ifq)		((ifq)->ifq_drops++)
229 #define	_IF_QLEN(ifq)		((ifq)->ifq_len)
230 
231 #define	_IF_ENQUEUE(ifq, m) do { 				\
232 	(m)->m_nextpkt = NULL;					\
233 	if ((ifq)->ifq_tail == NULL) 				\
234 		(ifq)->ifq_head = m; 				\
235 	else 							\
236 		(ifq)->ifq_tail->m_nextpkt = m; 		\
237 	(ifq)->ifq_tail = m; 					\
238 	(ifq)->ifq_len++; 					\
239 } while (0)
240 
241 #define IF_ENQUEUE(ifq, m) do {					\
242 	IF_LOCK(ifq); 						\
243 	_IF_ENQUEUE(ifq, m); 					\
244 	IF_UNLOCK(ifq); 					\
245 } while (0)
246 
247 #define	_IF_PREPEND(ifq, m) do {				\
248 	(m)->m_nextpkt = (ifq)->ifq_head; 			\
249 	if ((ifq)->ifq_tail == NULL) 				\
250 		(ifq)->ifq_tail = (m); 				\
251 	(ifq)->ifq_head = (m); 					\
252 	(ifq)->ifq_len++; 					\
253 } while (0)
254 
255 #define IF_PREPEND(ifq, m) do {		 			\
256 	IF_LOCK(ifq); 						\
257 	_IF_PREPEND(ifq, m); 					\
258 	IF_UNLOCK(ifq); 					\
259 } while (0)
260 
261 #define	_IF_DEQUEUE(ifq, m) do { 				\
262 	(m) = (ifq)->ifq_head; 					\
263 	if (m) { 						\
264 		if (((ifq)->ifq_head = (m)->m_nextpkt) == 0) 	\
265 			(ifq)->ifq_tail = NULL; 		\
266 		(m)->m_nextpkt = NULL; 				\
267 		(ifq)->ifq_len--; 				\
268 	} 							\
269 } while (0)
270 
271 #define IF_DEQUEUE(ifq, m) do { 				\
272 	IF_LOCK(ifq); 						\
273 	_IF_DEQUEUE(ifq, m); 					\
274 	IF_UNLOCK(ifq); 					\
275 } while (0)
276 
277 #define IF_DRAIN(ifq) do { 					\
278 	struct mbuf *m; 					\
279 	IF_LOCK(ifq); 						\
280 	for (;;) { 						\
281 		_IF_DEQUEUE(ifq, m); 				\
282 		if (m == NULL) 					\
283 			break; 					\
284 		m_freem(m); 					\
285 	} 							\
286 	IF_UNLOCK(ifq); 					\
287 } while (0)
288 
289 #ifdef _KERNEL
290 #define	IF_HANDOFF(ifq, m, ifp)			if_handoff(ifq, m, ifp, 0)
291 #define	IF_HANDOFF_ADJ(ifq, m, ifp, adj)	if_handoff(ifq, m, ifp, adj)
292 
293 static __inline int
294 if_handoff(struct ifqueue *ifq, struct mbuf *m, struct ifnet *ifp, int adjust)
295 {
296 	int active = 0;
297 
298 	IF_LOCK(ifq);
299 	if (_IF_QFULL(ifq)) {
300 		_IF_DROP(ifq);
301 		IF_UNLOCK(ifq);
302 		m_freem(m);
303 		return (0);
304 	}
305 	if (ifp != NULL) {
306 		ifp->if_obytes += m->m_pkthdr.len + adjust;
307 		if (m->m_flags & M_MCAST)
308 			ifp->if_omcasts++;
309 		active = ifp->if_flags & IFF_OACTIVE;
310 	}
311 	_IF_ENQUEUE(ifq, m);
312 	IF_UNLOCK(ifq);
313 	if (ifp != NULL && !active)
314 		(*ifp->if_start)(ifp);
315 	return (1);
316 }
317 
318 /*
319  * 72 was chosen below because it is the size of a TCP/IP
320  * header (40) + the minimum mss (32).
321  */
322 #define	IF_MINMTU	72
323 #define	IF_MAXMTU	65535
324 
325 #endif /* _KERNEL */
326 
327 /*
328  * The ifaddr structure contains information about one address
329  * of an interface.  They are maintained by the different address families,
330  * are allocated and attached when an address is set, and are linked
331  * together so all addresses for an interface can be located.
332  */
333 struct ifaddr {
334 	struct	sockaddr *ifa_addr;	/* address of interface */
335 	struct	sockaddr *ifa_dstaddr;	/* other end of p-to-p link */
336 #define	ifa_broadaddr	ifa_dstaddr	/* broadcast address interface */
337 	struct	sockaddr *ifa_netmask;	/* used to determine subnet */
338 	struct	if_data if_data;	/* not all members are meaningful */
339 	struct	ifnet *ifa_ifp;		/* back-pointer to interface */
340 	TAILQ_ENTRY(ifaddr) ifa_link;	/* queue macro glue */
341 	void	(*ifa_rtrequest)	/* check or clean routes (+ or -)'d */
342 		(int, struct rtentry *, struct rt_addrinfo *);
343 	u_short	ifa_flags;		/* mostly rt_flags for cloning */
344 	u_int	ifa_refcnt;		/* references to this structure */
345 	int	ifa_metric;		/* cost of going out this interface */
346 #ifdef notdef
347 	struct	rtentry *ifa_rt;	/* XXXX for ROUTETOIF ????? */
348 #endif
349 	int (*ifa_claim_addr)		/* check if an addr goes to this if */
350 		(struct ifaddr *, struct sockaddr *);
351 	struct mtx ifa_mtx;
352 };
353 #define	IFA_ROUTE	RTF_UP		/* route installed */
354 
355 /* for compatibility with other BSDs */
356 #define	ifa_list	ifa_link
357 
358 #define	IFA_LOCK_INIT(ifa)	\
359     mtx_init(&(ifa)->ifa_mtx, "ifaddr", NULL, MTX_DEF)
360 #define	IFA_LOCK(ifa)		mtx_lock(&(ifa)->ifa_mtx)
361 #define	IFA_UNLOCK(ifa)		mtx_unlock(&(ifa)->ifa_mtx)
362 #define	IFA_DESTROY(ifa)	mtx_destroy(&(ifa)->ifa_mtx)
363 
364 /*
365  * The prefix structure contains information about one prefix
366  * of an interface.  They are maintained by the different address families,
367  * are allocated and attached when a prefix or an address is set,
368  * and are linked together so all prefixes for an interface can be located.
369  */
370 struct ifprefix {
371 	struct	sockaddr *ifpr_prefix;	/* prefix of interface */
372 	struct	ifnet *ifpr_ifp;	/* back-pointer to interface */
373 	TAILQ_ENTRY(ifprefix) ifpr_list; /* queue macro glue */
374 	u_char	ifpr_plen;		/* prefix length in bits */
375 	u_char	ifpr_type;		/* protocol dependent prefix type */
376 };
377 
378 /*
379  * Multicast address structure.  This is analogous to the ifaddr
380  * structure except that it keeps track of multicast addresses.
381  * Also, the reference count here is a count of requests for this
382  * address, not a count of pointers to this structure.
383  */
384 struct ifmultiaddr {
385 	TAILQ_ENTRY(ifmultiaddr) ifma_link; /* queue macro glue */
386 	struct	sockaddr *ifma_addr; 	/* address this membership is for */
387 	struct	sockaddr *ifma_lladdr;	/* link-layer translation, if any */
388 	struct	ifnet *ifma_ifp;	/* back-pointer to interface */
389 	u_int	ifma_refcount;		/* reference count */
390 	void	*ifma_protospec;	/* protocol-specific state, if any */
391 };
392 
393 #ifdef _KERNEL
394 #define	IFAFREE(ifa)					\
395 	do {						\
396 		IFA_LOCK(ifa);				\
397 		KASSERT((ifa)->ifa_refcnt > 0,		\
398 		    ("ifa %p !(ifa_refcnt > 0)", ifa));	\
399 		if (--(ifa)->ifa_refcnt == 0) {		\
400 			IFA_DESTROY(ifa);		\
401 			free(ifa, M_IFADDR);		\
402 		} else 					\
403 			IFA_UNLOCK(ifa);		\
404 	} while (0)
405 
406 #define IFAREF(ifa)					\
407 	do {						\
408 		IFA_LOCK(ifa);				\
409 		++(ifa)->ifa_refcnt;			\
410 		IFA_UNLOCK(ifa);			\
411 	} while (0)
412 
413 extern	struct mtx ifnet_lock;
414 #define	IFNET_LOCK_INIT() \
415     mtx_init(&ifnet_lock, "ifnet", NULL, MTX_DEF | MTX_RECURSE)
416 #define	IFNET_WLOCK()		mtx_lock(&ifnet_lock)
417 #define	IFNET_WUNLOCK()		mtx_unlock(&ifnet_lock)
418 #define	IFNET_RLOCK()		IFNET_WLOCK()
419 #define	IFNET_RUNLOCK()		IFNET_WUNLOCK()
420 
421 struct ifindex_entry {
422 	struct	ifnet *ife_ifnet;
423 	struct	ifaddr *ife_ifnet_addr;
424 	dev_t	ife_dev;
425 };
426 
427 #define ifnet_byindex(idx)	ifindex_table[(idx)].ife_ifnet
428 #define ifaddr_byindex(idx)	ifindex_table[(idx)].ife_ifnet_addr
429 #define ifdev_byindex(idx)	ifindex_table[(idx)].ife_dev
430 
431 extern	struct ifnethead ifnet;
432 extern	struct ifindex_entry *ifindex_table;
433 extern	int ifqmaxlen;
434 extern	struct ifnet *loif;	/* first loopback interface */
435 extern	int if_index;
436 
437 int	if_addmulti(struct ifnet *, struct sockaddr *, struct ifmultiaddr **);
438 int	if_allmulti(struct ifnet *, int);
439 void	if_attach(struct ifnet *);
440 int	if_delmulti(struct ifnet *, struct sockaddr *);
441 void	if_detach(struct ifnet *);
442 void	if_down(struct ifnet *);
443 int	if_printf(struct ifnet *, const char *, ...) __printflike(2, 3);
444 void	if_route(struct ifnet *, int flag, int fam);
445 int	if_setlladdr(struct ifnet *, const u_char *, int);
446 void	if_unroute(struct ifnet *, int flag, int fam);
447 void	if_up(struct ifnet *);
448 /*void	ifinit(void);*/ /* declared in systm.h for main() */
449 int	ifioctl(struct socket *, u_long, caddr_t, struct thread *);
450 int	ifpromisc(struct ifnet *, int);
451 struct	ifnet *ifunit(const char *);
452 struct	ifnet *if_withname(struct sockaddr *);
453 
454 int	if_poll_recv_slow(struct ifnet *ifp, int *quotap);
455 void	if_poll_xmit_slow(struct ifnet *ifp, int *quotap);
456 void	if_poll_throttle(void);
457 void	if_poll_unthrottle(void *);
458 void	if_poll_init(void);
459 void	if_poll(void);
460 
461 struct	ifaddr *ifa_ifwithaddr(struct sockaddr *);
462 struct	ifaddr *ifa_ifwithdstaddr(struct sockaddr *);
463 struct	ifaddr *ifa_ifwithnet(struct sockaddr *);
464 struct	ifaddr *ifa_ifwithroute(int, struct sockaddr *, struct sockaddr *);
465 struct	ifaddr *ifaof_ifpforaddr(struct sockaddr *, struct ifnet *);
466 
467 struct	ifmultiaddr *ifmaof_ifpforaddr(struct sockaddr *, struct ifnet *);
468 int	if_simloop(struct ifnet *ifp, struct mbuf *m, int af, int hlen);
469 
470 void	if_clone_attach(struct if_clone *);
471 void	if_clone_detach(struct if_clone *);
472 
473 int	if_clone_create(char *, int);
474 int	if_clone_destroy(const char *);
475 
476 #define IF_LLADDR(ifp)							\
477     LLADDR((struct sockaddr_dl *) ifaddr_byindex((ifp)->if_index)->ifa_addr)
478 
479 #ifdef DEVICE_POLLING
480 enum poll_cmd {	POLL_ONLY, POLL_AND_CHECK_STATUS, POLL_DEREGISTER };
481 
482 typedef	void poll_handler_t(struct ifnet *ifp, enum poll_cmd cmd, int count);
483 int    ether_poll_register(poll_handler_t *h, struct ifnet *ifp);
484 int    ether_poll_deregister(struct ifnet *ifp);
485 #endif /* DEVICE_POLLING */
486 
487 #endif /* _KERNEL */
488 
489 #endif /* !_NET_IF_VAR_H_ */
490