xref: /freebsd/sys/net/if_var.h (revision c4f6a2a9e1b1879b618c436ab4f56ff75c73a0f5)
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/_label.h>		/* struct label */
78 #include <sys/queue.h>		/* get TAILQ macros */
79 
80 #ifdef _KERNEL
81 #include <sys/mbuf.h>
82 #include <sys/systm.h>		/* XXX */
83 #endif /* _KERNEL */
84 #include <sys/lock.h>		/* XXX */
85 #include <sys/mutex.h>		/* XXX */
86 #include <sys/event.h>		/* XXX */
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(ifprefixhead, ifprefix);
91 TAILQ_HEAD(ifmultihead, ifmultiaddr);
92 
93 /*
94  * Structure defining a queue for a network interface.
95  */
96 struct	ifqueue {
97 	struct	mbuf *ifq_head;
98 	struct	mbuf *ifq_tail;
99 	int	ifq_len;
100 	int	ifq_maxlen;
101 	int	ifq_drops;
102 	struct	mtx ifq_mtx;
103 };
104 
105 /*
106  * Structure defining a network interface.
107  *
108  * (Would like to call this struct ``if'', but C isn't PL/1.)
109  */
110 
111 /*
112  * NB: For FreeBSD, it is assumed that each NIC driver's softc starts with
113  * one of these structures, typically held within an arpcom structure.
114  *
115  *	struct <foo>_softc {
116  *		struct arpcom {
117  *			struct  ifnet ac_if;
118  *			...
119  *		} <arpcom> ;
120  *		...
121  *	};
122  *
123  * The assumption is used in a number of places, including many
124  * files in sys/net, device drivers, and sys/dev/mii.c:miibus_attach().
125  *
126  * Unfortunately devices' softc are opaque, so we depend on this layout
127  * to locate the struct ifnet from the softc in the generic code.
128  *
129  */
130 struct ifnet {
131 	void	*if_softc;		/* pointer to driver state */
132 	char	*if_name;		/* name, e.g. ``en'' or ``lo'' */
133 	TAILQ_ENTRY(ifnet) if_link; 	/* all struct ifnets are chained */
134 	struct	ifaddrhead if_addrhead;	/* linked list of addresses per if */
135 	struct	klist if_klist;		/* events attached to this if */
136 	int	if_pcount;		/* number of promiscuous listeners */
137 	struct	bpf_if *if_bpf;		/* packet filter structure */
138 	u_short	if_index;		/* numeric abbreviation for this if  */
139 	short	if_unit;		/* sub-unit for lower level driver */
140 	short	if_timer;		/* time 'til if_watchdog called */
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_start)		/* initiate output routine */
155 		(struct ifnet *);
156 	int	(*if_done)		/* output complete routine */
157 		(struct ifnet *);	/* (XXX not used; fake prototype) */
158 	int	(*if_ioctl)		/* ioctl routine */
159 		(struct ifnet *, u_long, caddr_t);
160 	void	(*if_watchdog)		/* timer routine */
161 		(struct ifnet *);
162 	int	(*if_poll_recv)		/* polled receive routine */
163 		(struct ifnet *, int *);
164 	int	(*if_poll_xmit)		/* polled transmit routine */
165 		(struct ifnet *, int *);
166 	void	(*if_poll_intren)	/* polled interrupt reenable routine */
167 		(struct ifnet *);
168 	void	(*if_poll_slowinput)	/* input routine for slow devices */
169 		(struct ifnet *, struct mbuf *);
170 	void	(*if_init)		/* Init routine */
171 		(void *);
172 	int	(*if_resolvemulti)	/* validate/resolve multicast */
173 		(struct ifnet *, struct sockaddr **, struct sockaddr *);
174 	struct	ifqueue if_snd;		/* output queue */
175 	struct	ifqueue *if_poll_slowq;	/* input queue for slow devices */
176 	struct	ifprefixhead if_prefixhead; /* list of prefixes per if */
177 	u_int8_t *if_broadcastaddr;	/* linklevel broadcast bytestring */
178 	struct	label if_label;		/* interface MAC label */
179 };
180 
181 typedef void if_init_f_t(void *);
182 
183 #define	if_mtu		if_data.ifi_mtu
184 #define	if_type		if_data.ifi_type
185 #define if_physical	if_data.ifi_physical
186 #define	if_addrlen	if_data.ifi_addrlen
187 #define	if_hdrlen	if_data.ifi_hdrlen
188 #define	if_metric	if_data.ifi_metric
189 #define	if_baudrate	if_data.ifi_baudrate
190 #define	if_hwassist	if_data.ifi_hwassist
191 #define	if_ipackets	if_data.ifi_ipackets
192 #define	if_ierrors	if_data.ifi_ierrors
193 #define	if_opackets	if_data.ifi_opackets
194 #define	if_oerrors	if_data.ifi_oerrors
195 #define	if_collisions	if_data.ifi_collisions
196 #define	if_ibytes	if_data.ifi_ibytes
197 #define	if_obytes	if_data.ifi_obytes
198 #define	if_imcasts	if_data.ifi_imcasts
199 #define	if_omcasts	if_data.ifi_omcasts
200 #define	if_iqdrops	if_data.ifi_iqdrops
201 #define	if_noproto	if_data.ifi_noproto
202 #define	if_lastchange	if_data.ifi_lastchange
203 #define if_recvquota	if_data.ifi_recvquota
204 #define	if_xmitquota	if_data.ifi_xmitquota
205 #define if_rawoutput(if, m, sa) if_output(if, m, sa, (struct rtentry *)0)
206 
207 /* for compatibility with other BSDs */
208 #define	if_addrlist	if_addrhead
209 #define	if_list		if_link
210 
211 /*
212  * Bit values in if_ipending
213  */
214 #define	IFI_RECV	1	/* I want to receive */
215 #define	IFI_XMIT	2	/* I want to transmit */
216 
217 /*
218  * Output queues (ifp->if_snd) and slow device input queues (*ifp->if_slowq)
219  * are queues of messages stored on ifqueue structures
220  * (defined above).  Entries are added to and deleted from these structures
221  * by these macros, which should be called with ipl raised to splimp().
222  */
223 #define IF_LOCK(ifq)		mtx_lock(&(ifq)->ifq_mtx)
224 #define IF_UNLOCK(ifq)		mtx_unlock(&(ifq)->ifq_mtx)
225 #define	_IF_QFULL(ifq)		((ifq)->ifq_len >= (ifq)->ifq_maxlen)
226 #define	_IF_DROP(ifq)		((ifq)->ifq_drops++)
227 #define	_IF_QLEN(ifq)		((ifq)->ifq_len)
228 
229 #define	_IF_ENQUEUE(ifq, m) do { 				\
230 	(m)->m_nextpkt = NULL;					\
231 	if ((ifq)->ifq_tail == NULL) 				\
232 		(ifq)->ifq_head = m; 				\
233 	else 							\
234 		(ifq)->ifq_tail->m_nextpkt = m; 		\
235 	(ifq)->ifq_tail = m; 					\
236 	(ifq)->ifq_len++; 					\
237 } while (0)
238 
239 #define IF_ENQUEUE(ifq, m) do {					\
240 	IF_LOCK(ifq); 						\
241 	_IF_ENQUEUE(ifq, m); 					\
242 	IF_UNLOCK(ifq); 					\
243 } while (0)
244 
245 #define	_IF_PREPEND(ifq, m) do {				\
246 	(m)->m_nextpkt = (ifq)->ifq_head; 			\
247 	if ((ifq)->ifq_tail == NULL) 				\
248 		(ifq)->ifq_tail = (m); 				\
249 	(ifq)->ifq_head = (m); 					\
250 	(ifq)->ifq_len++; 					\
251 } while (0)
252 
253 #define IF_PREPEND(ifq, m) do {		 			\
254 	IF_LOCK(ifq); 						\
255 	_IF_PREPEND(ifq, m); 					\
256 	IF_UNLOCK(ifq); 					\
257 } while (0)
258 
259 #define	_IF_DEQUEUE(ifq, m) do { 				\
260 	(m) = (ifq)->ifq_head; 					\
261 	if (m) { 						\
262 		if (((ifq)->ifq_head = (m)->m_nextpkt) == 0) 	\
263 			(ifq)->ifq_tail = NULL; 		\
264 		(m)->m_nextpkt = NULL; 				\
265 		(ifq)->ifq_len--; 				\
266 	} 							\
267 } while (0)
268 
269 #define IF_DEQUEUE(ifq, m) do { 				\
270 	IF_LOCK(ifq); 						\
271 	_IF_DEQUEUE(ifq, m); 					\
272 	IF_UNLOCK(ifq); 					\
273 } while (0)
274 
275 #define IF_DRAIN(ifq) do { 					\
276 	struct mbuf *m; 					\
277 	IF_LOCK(ifq); 						\
278 	for (;;) { 						\
279 		_IF_DEQUEUE(ifq, m); 				\
280 		if (m == NULL) 					\
281 			break; 					\
282 		m_freem(m); 					\
283 	} 							\
284 	IF_UNLOCK(ifq); 					\
285 } while (0)
286 
287 #ifdef _KERNEL
288 #define	IF_HANDOFF(ifq, m, ifp)			if_handoff(ifq, m, ifp, 0)
289 #define	IF_HANDOFF_ADJ(ifq, m, ifp, adj)	if_handoff(ifq, m, ifp, adj)
290 
291 static __inline int
292 if_handoff(struct ifqueue *ifq, struct mbuf *m, struct ifnet *ifp, int adjust)
293 {
294 	int active = 0;
295 
296 	IF_LOCK(ifq);
297 	if (_IF_QFULL(ifq)) {
298 		_IF_DROP(ifq);
299 		IF_UNLOCK(ifq);
300 		m_freem(m);
301 		return (0);
302 	}
303 	if (ifp != NULL) {
304 		ifp->if_obytes += m->m_pkthdr.len + adjust;
305 		if (m->m_flags & M_MCAST)
306 			ifp->if_omcasts++;
307 		active = ifp->if_flags & IFF_OACTIVE;
308 	}
309 	_IF_ENQUEUE(ifq, m);
310 	IF_UNLOCK(ifq);
311 	if (ifp != NULL && !active)
312 		(*ifp->if_start)(ifp);
313 	return (1);
314 }
315 
316 /*
317  * 72 was chosen below because it is the size of a TCP/IP
318  * header (40) + the minimum mss (32).
319  */
320 #define	IF_MINMTU	72
321 #define	IF_MAXMTU	65535
322 
323 #endif /* _KERNEL */
324 
325 /*
326  * The ifaddr structure contains information about one address
327  * of an interface.  They are maintained by the different address families,
328  * are allocated and attached when an address is set, and are linked
329  * together so all addresses for an interface can be located.
330  */
331 struct ifaddr {
332 	struct	sockaddr *ifa_addr;	/* address of interface */
333 	struct	sockaddr *ifa_dstaddr;	/* other end of p-to-p link */
334 #define	ifa_broadaddr	ifa_dstaddr	/* broadcast address interface */
335 	struct	sockaddr *ifa_netmask;	/* used to determine subnet */
336 	struct	if_data if_data;	/* not all members are meaningful */
337 	struct	ifnet *ifa_ifp;		/* back-pointer to interface */
338 	TAILQ_ENTRY(ifaddr) ifa_link;	/* queue macro glue */
339 	void	(*ifa_rtrequest)	/* check or clean routes (+ or -)'d */
340 		(int, struct rtentry *, struct rt_addrinfo *);
341 	u_short	ifa_flags;		/* mostly rt_flags for cloning */
342 	u_int	ifa_refcnt;		/* references to this structure */
343 	int	ifa_metric;		/* cost of going out this interface */
344 #ifdef notdef
345 	struct	rtentry *ifa_rt;	/* XXXX for ROUTETOIF ????? */
346 #endif
347 	int (*ifa_claim_addr)		/* check if an addr goes to this if */
348 		(struct ifaddr *, struct sockaddr *);
349 
350 };
351 #define	IFA_ROUTE	RTF_UP		/* route installed */
352 
353 /* for compatibility with other BSDs */
354 #define	ifa_list	ifa_link
355 
356 /*
357  * The prefix structure contains information about one prefix
358  * of an interface.  They are maintained by the different address families,
359  * are allocated and attached when an prefix or an address is set,
360  * and are linked together so all prefixes for an interface can be located.
361  */
362 struct ifprefix {
363 	struct	sockaddr *ifpr_prefix;	/* prefix of interface */
364 	struct	ifnet *ifpr_ifp;	/* back-pointer to interface */
365 	TAILQ_ENTRY(ifprefix) ifpr_list; /* queue macro glue */
366 	u_char	ifpr_plen;		/* prefix length in bits */
367 	u_char	ifpr_type;		/* protocol dependent prefix type */
368 };
369 
370 /*
371  * Multicast address structure.  This is analogous to the ifaddr
372  * structure except that it keeps track of multicast addresses.
373  * Also, the reference count here is a count of requests for this
374  * address, not a count of pointers to this structure.
375  */
376 struct ifmultiaddr {
377 	TAILQ_ENTRY(ifmultiaddr) ifma_link; /* queue macro glue */
378 	struct	sockaddr *ifma_addr; 	/* address this membership is for */
379 	struct	sockaddr *ifma_lladdr;	/* link-layer translation, if any */
380 	struct	ifnet *ifma_ifp;	/* back-pointer to interface */
381 	u_int	ifma_refcount;		/* reference count */
382 	void	*ifma_protospec;	/* protocol-specific state, if any */
383 };
384 
385 #ifdef _KERNEL
386 #define	IFAFREE(ifa) \
387 	do { \
388 		if ((ifa)->ifa_refcnt <= 0) \
389 			ifafree(ifa); \
390 		else \
391 			(ifa)->ifa_refcnt--; \
392 	} while (0)
393 
394 struct ifindex_entry {
395 	struct	ifnet *ife_ifnet;
396 	struct	ifaddr *ife_ifnet_addr;
397 	dev_t	ife_dev;
398 };
399 
400 #define ifnet_byindex(idx)	ifindex_table[(idx)].ife_ifnet
401 #define ifaddr_byindex(idx)	ifindex_table[(idx)].ife_ifnet_addr
402 #define ifdev_byindex(idx)	ifindex_table[(idx)].ife_dev
403 
404 extern	struct ifnethead ifnet;
405 extern	struct ifindex_entry *ifindex_table;
406 extern	int ifqmaxlen;
407 extern	struct ifnet *loif;	/* first loopback interface */
408 extern	int if_index;
409 
410 void	ether_ifattach(struct ifnet *, int);
411 void	ether_ifdetach(struct ifnet *, int);
412 void	ether_input(struct ifnet *, struct ether_header *, struct mbuf *);
413 void	ether_demux(struct ifnet *, struct ether_header *, struct mbuf *);
414 int	ether_output(struct ifnet *,
415 	   struct mbuf *, struct sockaddr *, struct rtentry *);
416 int	ether_output_frame(struct ifnet *, struct mbuf *);
417 int	ether_ioctl(struct ifnet *, int, caddr_t);
418 
419 int	if_addmulti(struct ifnet *, struct sockaddr *, struct ifmultiaddr **);
420 int	if_allmulti(struct ifnet *, int);
421 void	if_attach(struct ifnet *);
422 int	if_delmulti(struct ifnet *, struct sockaddr *);
423 void	if_detach(struct ifnet *);
424 void	if_down(struct ifnet *);
425 void	if_route(struct ifnet *, int flag, int fam);
426 int	if_setlladdr(struct ifnet *, const u_char *, int);
427 void	if_unroute(struct ifnet *, int flag, int fam);
428 void	if_up(struct ifnet *);
429 /*void	ifinit(void);*/ /* declared in systm.h for main() */
430 int	ifioctl(struct socket *, u_long, caddr_t, struct thread *);
431 int	ifpromisc(struct ifnet *, int);
432 struct	ifnet *ifunit(const char *);
433 struct	ifnet *if_withname(struct sockaddr *);
434 
435 int	if_poll_recv_slow(struct ifnet *ifp, int *quotap);
436 void	if_poll_xmit_slow(struct ifnet *ifp, int *quotap);
437 void	if_poll_throttle(void);
438 void	if_poll_unthrottle(void *);
439 void	if_poll_init(void);
440 void	if_poll(void);
441 
442 struct	ifaddr *ifa_ifwithaddr(struct sockaddr *);
443 struct	ifaddr *ifa_ifwithdstaddr(struct sockaddr *);
444 struct	ifaddr *ifa_ifwithnet(struct sockaddr *);
445 struct	ifaddr *ifa_ifwithroute(int, struct sockaddr *, struct sockaddr *);
446 struct	ifaddr *ifaof_ifpforaddr(struct sockaddr *, struct ifnet *);
447 void	ifafree(struct ifaddr *);
448 
449 struct	ifmultiaddr *ifmaof_ifpforaddr(struct sockaddr *, struct ifnet *);
450 int	if_simloop(struct ifnet *ifp, struct mbuf *m, int af, int hlen);
451 
452 void	if_clone_attach(struct if_clone *);
453 void	if_clone_detach(struct if_clone *);
454 
455 int	if_clone_create(char *, int);
456 int	if_clone_destroy(const char *);
457 
458 #define IF_LLADDR(ifp)							\
459     LLADDR((struct sockaddr_dl *) ifaddr_byindex((ifp)->if_index)->ifa_addr)
460 
461 #ifdef DEVICE_POLLING
462 enum poll_cmd {	POLL_ONLY, POLL_AND_CHECK_STATUS, POLL_DEREGISTER };
463 
464 typedef	void poll_handler_t(struct ifnet *ifp, enum poll_cmd cmd, int count);
465 int    ether_poll_register(poll_handler_t *h, struct ifnet *ifp);
466 int    ether_poll_deregister(struct ifnet *ifp);
467 #endif /* DEVICE_POLLING */
468 
469 #endif /* _KERNEL */
470 
471 #endif /* !_NET_IF_VAR_H_ */
472