xref: /freebsd/sys/net/if_var.h (revision c17d43407fe04133a94055b0dbc7ea8965654a9f)
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 a 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 a 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/queue.h>		/* get TAILQ macros */
78 
79 #ifdef _KERNEL
80 #include <sys/mbuf.h>
81 #include <sys/systm.h>		/* XXX */
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 	short	if_flags;		/* up/down, broadcast, etc. */
141 	int	if_capabilities;	/* interface capabilities */
142 	int	if_capenable;		/* enabled features */
143 	int	if_ipending;		/* interrupts pending */
144 	void	*if_linkmib;		/* link-type-specific MIB data */
145 	size_t	if_linkmiblen;		/* length of above data */
146 	struct	if_data if_data;
147 	struct	ifmultihead if_multiaddrs; /* multicast addresses configured */
148 	int	if_amcount;		/* number of all-multicast requests */
149 /* procedure handles */
150 	int	(*if_output)		/* output routine (enqueue) */
151 		(struct ifnet *, struct mbuf *, struct sockaddr *,
152 		     struct rtentry *);
153 	void	(*if_start)		/* initiate output routine */
154 		(struct ifnet *);
155 	int	(*if_done)		/* output complete routine */
156 		(struct ifnet *);	/* (XXX not used; fake prototype) */
157 	int	(*if_ioctl)		/* ioctl routine */
158 		(struct ifnet *, u_long, caddr_t);
159 	void	(*if_watchdog)		/* timer routine */
160 		(struct ifnet *);
161 	int	(*if_poll_recv)		/* polled receive routine */
162 		(struct ifnet *, int *);
163 	int	(*if_poll_xmit)		/* polled transmit routine */
164 		(struct ifnet *, int *);
165 	void	(*if_poll_intren)	/* polled interrupt reenable routine */
166 		(struct ifnet *);
167 	void	(*if_poll_slowinput)	/* input routine for slow devices */
168 		(struct ifnet *, struct mbuf *);
169 	void	(*if_init)		/* Init routine */
170 		(void *);
171 	int	(*if_resolvemulti)	/* validate/resolve multicast */
172 		(struct ifnet *, struct sockaddr **, struct sockaddr *);
173 	struct	ifqueue if_snd;		/* output queue */
174 	struct	ifqueue *if_poll_slowq;	/* input queue for slow devices */
175 	struct	ifprefixhead if_prefixhead; /* list of prefixes per if */
176 	u_int8_t *if_broadcastaddr;	/* linklevel broadcast bytestring */
177 };
178 
179 typedef void if_init_f_t(void *);
180 
181 #define	if_mtu		if_data.ifi_mtu
182 #define	if_type		if_data.ifi_type
183 #define if_physical	if_data.ifi_physical
184 #define	if_addrlen	if_data.ifi_addrlen
185 #define	if_hdrlen	if_data.ifi_hdrlen
186 #define	if_metric	if_data.ifi_metric
187 #define	if_baudrate	if_data.ifi_baudrate
188 #define	if_hwassist	if_data.ifi_hwassist
189 #define	if_ipackets	if_data.ifi_ipackets
190 #define	if_ierrors	if_data.ifi_ierrors
191 #define	if_opackets	if_data.ifi_opackets
192 #define	if_oerrors	if_data.ifi_oerrors
193 #define	if_collisions	if_data.ifi_collisions
194 #define	if_ibytes	if_data.ifi_ibytes
195 #define	if_obytes	if_data.ifi_obytes
196 #define	if_imcasts	if_data.ifi_imcasts
197 #define	if_omcasts	if_data.ifi_omcasts
198 #define	if_iqdrops	if_data.ifi_iqdrops
199 #define	if_noproto	if_data.ifi_noproto
200 #define	if_lastchange	if_data.ifi_lastchange
201 #define if_recvquota	if_data.ifi_recvquota
202 #define	if_xmitquota	if_data.ifi_xmitquota
203 #define if_rawoutput(if, m, sa) if_output(if, m, sa, (struct rtentry *)0)
204 
205 /* for compatibility with other BSDs */
206 #define	if_addrlist	if_addrhead
207 #define	if_list		if_link
208 
209 /*
210  * Bit values in if_ipending
211  */
212 #define	IFI_RECV	1	/* I want to receive */
213 #define	IFI_XMIT	2	/* I want to transmit */
214 
215 /*
216  * Output queues (ifp->if_snd) and slow device input queues (*ifp->if_slowq)
217  * are queues of messages stored on ifqueue structures
218  * (defined above).  Entries are added to and deleted from these structures
219  * by these macros, which should be called with ipl raised to splimp().
220  */
221 #define IF_LOCK(ifq)		mtx_lock(&(ifq)->ifq_mtx)
222 #define IF_UNLOCK(ifq)		mtx_unlock(&(ifq)->ifq_mtx)
223 #define	_IF_QFULL(ifq)		((ifq)->ifq_len >= (ifq)->ifq_maxlen)
224 #define	_IF_DROP(ifq)		((ifq)->ifq_drops++)
225 #define	_IF_QLEN(ifq)		((ifq)->ifq_len)
226 
227 #define	_IF_ENQUEUE(ifq, m) do { 				\
228 	(m)->m_nextpkt = NULL;					\
229 	if ((ifq)->ifq_tail == NULL) 				\
230 		(ifq)->ifq_head = m; 				\
231 	else 							\
232 		(ifq)->ifq_tail->m_nextpkt = m; 		\
233 	(ifq)->ifq_tail = m; 					\
234 	(ifq)->ifq_len++; 					\
235 } while (0)
236 
237 #define IF_ENQUEUE(ifq, m) do {					\
238 	IF_LOCK(ifq); 						\
239 	_IF_ENQUEUE(ifq, m); 					\
240 	IF_UNLOCK(ifq); 					\
241 } while (0)
242 
243 #define	_IF_PREPEND(ifq, m) do {				\
244 	(m)->m_nextpkt = (ifq)->ifq_head; 			\
245 	if ((ifq)->ifq_tail == NULL) 				\
246 		(ifq)->ifq_tail = (m); 				\
247 	(ifq)->ifq_head = (m); 					\
248 	(ifq)->ifq_len++; 					\
249 } while (0)
250 
251 #define IF_PREPEND(ifq, m) do {		 			\
252 	IF_LOCK(ifq); 						\
253 	_IF_PREPEND(ifq, m); 					\
254 	IF_UNLOCK(ifq); 					\
255 } while (0)
256 
257 #define	_IF_DEQUEUE(ifq, m) do { 				\
258 	(m) = (ifq)->ifq_head; 					\
259 	if (m) { 						\
260 		if (((ifq)->ifq_head = (m)->m_nextpkt) == 0) 	\
261 			(ifq)->ifq_tail = NULL; 		\
262 		(m)->m_nextpkt = NULL; 				\
263 		(ifq)->ifq_len--; 				\
264 	} 							\
265 } while (0)
266 
267 #define IF_DEQUEUE(ifq, m) do { 				\
268 	IF_LOCK(ifq); 						\
269 	_IF_DEQUEUE(ifq, m); 					\
270 	IF_UNLOCK(ifq); 					\
271 } while (0)
272 
273 #define IF_DRAIN(ifq) do { 					\
274 	struct mbuf *m; 					\
275 	IF_LOCK(ifq); 						\
276 	for (;;) { 						\
277 		_IF_DEQUEUE(ifq, m); 				\
278 		if (m == NULL) 					\
279 			break; 					\
280 		m_freem(m); 					\
281 	} 							\
282 	IF_UNLOCK(ifq); 					\
283 } while (0)
284 
285 #ifdef _KERNEL
286 #define	IF_HANDOFF(ifq, m, ifp)			if_handoff(ifq, m, ifp, 0)
287 #define	IF_HANDOFF_ADJ(ifq, m, ifp, adj)	if_handoff(ifq, m, ifp, adj)
288 
289 static __inline int
290 if_handoff(struct ifqueue *ifq, struct mbuf *m, struct ifnet *ifp, int adjust)
291 {
292 	int active = 0;
293 
294 	IF_LOCK(ifq);
295 	if (_IF_QFULL(ifq)) {
296 		_IF_DROP(ifq);
297 		IF_UNLOCK(ifq);
298 		m_freem(m);
299 		return (0);
300 	}
301 	if (ifp != NULL) {
302 		ifp->if_obytes += m->m_pkthdr.len + adjust;
303 		if (m->m_flags & M_MCAST)
304 			ifp->if_omcasts++;
305 		active = ifp->if_flags & IFF_OACTIVE;
306 	}
307 	_IF_ENQUEUE(ifq, m);
308 	IF_UNLOCK(ifq);
309 	if (ifp != NULL && !active)
310 			(*ifp->if_start)(ifp);
311 	return (1);
312 }
313 
314 /*
315  * 72 was chosen below because it is the size of a TCP/IP
316  * header (40) + the minimum mss (32).
317  */
318 #define	IF_MINMTU	72
319 #define	IF_MAXMTU	65535
320 
321 #endif /* _KERNEL */
322 
323 /*
324  * The ifaddr structure contains information about one address
325  * of an interface.  They are maintained by the different address families,
326  * are allocated and attached when an address is set, and are linked
327  * together so all addresses for an interface can be located.
328  */
329 struct ifaddr {
330 	struct	sockaddr *ifa_addr;	/* address of interface */
331 	struct	sockaddr *ifa_dstaddr;	/* other end of p-to-p link */
332 #define	ifa_broadaddr	ifa_dstaddr	/* broadcast address interface */
333 	struct	sockaddr *ifa_netmask;	/* used to determine subnet */
334 	struct	if_data if_data;	/* not all members are meaningful */
335 	struct	ifnet *ifa_ifp;		/* back-pointer to interface */
336 	TAILQ_ENTRY(ifaddr) ifa_link;	/* queue macro glue */
337 	void	(*ifa_rtrequest)	/* check or clean routes (+ or -)'d */
338 		(int, struct rtentry *, struct rt_addrinfo *);
339 	u_short	ifa_flags;		/* mostly rt_flags for cloning */
340 	u_int	ifa_refcnt;		/* references to this structure */
341 	int	ifa_metric;		/* cost of going out this interface */
342 #ifdef notdef
343 	struct	rtentry *ifa_rt;	/* XXXX for ROUTETOIF ????? */
344 #endif
345 	int (*ifa_claim_addr)		/* check if an addr goes to this if */
346 		(struct ifaddr *, struct sockaddr *);
347 
348 };
349 #define	IFA_ROUTE	RTF_UP		/* route installed */
350 
351 /* for compatibility with other BSDs */
352 #define	ifa_list	ifa_link
353 
354 /*
355  * The prefix structure contains information about one prefix
356  * of an interface.  They are maintained by the different address families,
357  * are allocated and attached when an prefix or an address is set,
358  * and are linked together so all prefixes for an interface can be located.
359  */
360 struct ifprefix {
361 	struct	sockaddr *ifpr_prefix;	/* prefix of interface */
362 	struct	ifnet *ifpr_ifp;	/* back-pointer to interface */
363 	TAILQ_ENTRY(ifprefix) ifpr_list; /* queue macro glue */
364 	u_char	ifpr_plen;		/* prefix length in bits */
365 	u_char	ifpr_type;		/* protocol dependent prefix type */
366 };
367 
368 /*
369  * Multicast address structure.  This is analogous to the ifaddr
370  * structure except that it keeps track of multicast addresses.
371  * Also, the reference count here is a count of requests for this
372  * address, not a count of pointers to this structure.
373  */
374 struct ifmultiaddr {
375 	TAILQ_ENTRY(ifmultiaddr) ifma_link; /* queue macro glue */
376 	struct	sockaddr *ifma_addr; 	/* address this membership is for */
377 	struct	sockaddr *ifma_lladdr;	/* link-layer translation, if any */
378 	struct	ifnet *ifma_ifp;	/* back-pointer to interface */
379 	u_int	ifma_refcount;		/* reference count */
380 	void	*ifma_protospec;	/* protocol-specific state, if any */
381 };
382 
383 #ifdef _KERNEL
384 #define	IFAFREE(ifa) \
385 	do { \
386 		if ((ifa)->ifa_refcnt <= 0) \
387 			ifafree(ifa); \
388 		else \
389 			(ifa)->ifa_refcnt--; \
390 	} while (0)
391 
392 struct ifindex_entry {
393 	struct	ifnet *ife_ifnet;
394 	struct	ifaddr *ife_ifnet_addr;
395 	dev_t	ife_dev;
396 };
397 
398 #define ifnet_byindex(idx)	ifindex_table[(idx)].ife_ifnet
399 #define ifaddr_byindex(idx)	ifindex_table[(idx)].ife_ifnet_addr
400 #define ifdev_byindex(idx)	ifindex_table[(idx)].ife_dev
401 
402 extern	struct ifnethead ifnet;
403 extern	struct ifindex_entry *ifindex_table;
404 extern	int ifqmaxlen;
405 extern	struct ifnet *loif;	/* first loopback interface */
406 extern	int if_index;
407 
408 void	ether_ifattach(struct ifnet *, int);
409 void	ether_ifdetach(struct ifnet *, int);
410 void	ether_input(struct ifnet *, struct ether_header *, struct mbuf *);
411 void	ether_demux(struct ifnet *, struct ether_header *, struct mbuf *);
412 int	ether_output(struct ifnet *,
413 	   struct mbuf *, struct sockaddr *, struct rtentry *);
414 int	ether_output_frame(struct ifnet *, struct mbuf *);
415 int	ether_ioctl(struct ifnet *, int, caddr_t);
416 
417 int	if_addmulti(struct ifnet *, struct sockaddr *, struct ifmultiaddr **);
418 int	if_allmulti(struct ifnet *, int);
419 void	if_attach(struct ifnet *);
420 int	if_delmulti(struct ifnet *, struct sockaddr *);
421 void	if_detach(struct ifnet *);
422 void	if_down(struct ifnet *);
423 void	if_route(struct ifnet *, int flag, int fam);
424 int	if_setlladdr(struct ifnet *, const u_char *, int);
425 void	if_unroute(struct ifnet *, int flag, int fam);
426 void	if_up(struct ifnet *);
427 /*void	ifinit(void);*/ /* declared in systm.h for main() */
428 int	ifioctl(struct socket *, u_long, caddr_t, struct thread *);
429 int	ifpromisc(struct ifnet *, int);
430 struct	ifnet *ifunit(const char *);
431 struct	ifnet *if_withname(struct sockaddr *);
432 
433 int	if_poll_recv_slow(struct ifnet *ifp, int *quotap);
434 void	if_poll_xmit_slow(struct ifnet *ifp, int *quotap);
435 void	if_poll_throttle(void);
436 void	if_poll_unthrottle(void *);
437 void	if_poll_init(void);
438 void	if_poll(void);
439 
440 struct	ifaddr *ifa_ifwithaddr(struct sockaddr *);
441 struct	ifaddr *ifa_ifwithdstaddr(struct sockaddr *);
442 struct	ifaddr *ifa_ifwithnet(struct sockaddr *);
443 struct	ifaddr *ifa_ifwithroute(int, struct sockaddr *, struct sockaddr *);
444 struct	ifaddr *ifaof_ifpforaddr(struct sockaddr *, struct ifnet *);
445 void	ifafree(struct ifaddr *);
446 
447 struct	ifmultiaddr *ifmaof_ifpforaddr(struct sockaddr *, struct ifnet *);
448 int	if_simloop(struct ifnet *ifp, struct mbuf *m, int af, int hlen);
449 
450 void	if_clone_attach(struct if_clone *);
451 void	if_clone_detach(struct if_clone *);
452 
453 int	if_clone_create(char *, int);
454 int	if_clone_destroy(const char *);
455 
456 #define IF_LLADDR(ifp)							\
457     LLADDR((struct sockaddr_dl *) ifaddr_byindex((ifp)->if_index)->ifa_addr)
458 
459 #ifdef DEVICE_POLLING
460 enum poll_cmd {	POLL_ONLY, POLL_AND_CHECK_STATUS, POLL_DEREGISTER };
461 
462 typedef	void poll_handler_t(struct ifnet *ifp, enum poll_cmd cmd, int count);
463 int    ether_poll_register(poll_handler_t *h, struct ifnet *ifp);
464 int    ether_poll_deregister(struct ifnet *ifp);
465 #endif /* DEVICE_POLLING */
466 
467 #endif /* _KERNEL */
468 
469 #endif /* !_NET_IF_VAR_H_ */
470