xref: /freebsd/sys/net/if_var.h (revision a220d00e74dd245b4fca59c5eca0c53963686325)
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 ifnet {
115 	void	*if_softc;		/* pointer to driver state */
116 	char	*if_name;		/* name, e.g. ``en'' or ``lo'' */
117 	TAILQ_ENTRY(ifnet) if_link; 	/* all struct ifnets are chained */
118 	struct	ifaddrhead if_addrhead;	/* linked list of addresses per if */
119 	struct	klist if_klist;		/* events attached to this if */
120 	int	if_pcount;		/* number of promiscuous listeners */
121 	struct	bpf_if *if_bpf;		/* packet filter structure */
122 	u_short	if_index;		/* numeric abbreviation for this if  */
123 	short	if_unit;		/* sub-unit for lower level driver */
124 	short	if_timer;		/* time 'til if_watchdog called */
125 	short	if_flags;		/* up/down, broadcast, etc. */
126 	int	if_capabilities;	/* interface capabilities */
127 	int	if_capenable;		/* enabled features */
128 	int	if_mpsafe;		/* XXX TEMPORARY */
129 	int	if_ipending;		/* interrupts pending */
130 	void	*if_linkmib;		/* link-type-specific MIB data */
131 	size_t	if_linkmiblen;		/* length of above data */
132 	struct	if_data if_data;
133 	struct	ifmultihead if_multiaddrs; /* multicast addresses configured */
134 	int	if_amcount;		/* number of all-multicast requests */
135 /* procedure handles */
136 	int	(*if_output)		/* output routine (enqueue) */
137 		__P((struct ifnet *, struct mbuf *, struct sockaddr *,
138 		     struct rtentry *));
139 	void	(*if_start)		/* initiate output routine */
140 		__P((struct ifnet *));
141 	int	(*if_done)		/* output complete routine */
142 		__P((struct ifnet *));	/* (XXX not used; fake prototype) */
143 	int	(*if_ioctl)		/* ioctl routine */
144 		__P((struct ifnet *, u_long, caddr_t));
145 	void	(*if_watchdog)		/* timer routine */
146 		__P((struct ifnet *));
147 	int	(*if_poll_recv)		/* polled receive routine */
148 		__P((struct ifnet *, int *));
149 	int	(*if_poll_xmit)		/* polled transmit routine */
150 		__P((struct ifnet *, int *));
151 	void	(*if_poll_intren)	/* polled interrupt reenable routine */
152 		__P((struct ifnet *));
153 	void	(*if_poll_slowinput)	/* input routine for slow devices */
154 		__P((struct ifnet *, struct mbuf *));
155 	void	(*if_init)		/* Init routine */
156 		__P((void *));
157 	int	(*if_resolvemulti)	/* validate/resolve multicast */
158 		__P((struct ifnet *, struct sockaddr **, struct sockaddr *));
159 	struct	ifqueue if_snd;		/* output queue */
160 	struct	ifqueue *if_poll_slowq;	/* input queue for slow devices */
161 	struct	ifprefixhead if_prefixhead; /* list of prefixes per if */
162 	u_int8_t *if_broadcastaddr;	/* linklevel broadcast bytestring */
163 };
164 
165 typedef void if_init_f_t __P((void *));
166 
167 #define	if_mtu		if_data.ifi_mtu
168 #define	if_type		if_data.ifi_type
169 #define if_physical	if_data.ifi_physical
170 #define	if_addrlen	if_data.ifi_addrlen
171 #define	if_hdrlen	if_data.ifi_hdrlen
172 #define	if_metric	if_data.ifi_metric
173 #define	if_baudrate	if_data.ifi_baudrate
174 #define	if_hwassist	if_data.ifi_hwassist
175 #define	if_ipackets	if_data.ifi_ipackets
176 #define	if_ierrors	if_data.ifi_ierrors
177 #define	if_opackets	if_data.ifi_opackets
178 #define	if_oerrors	if_data.ifi_oerrors
179 #define	if_collisions	if_data.ifi_collisions
180 #define	if_ibytes	if_data.ifi_ibytes
181 #define	if_obytes	if_data.ifi_obytes
182 #define	if_imcasts	if_data.ifi_imcasts
183 #define	if_omcasts	if_data.ifi_omcasts
184 #define	if_iqdrops	if_data.ifi_iqdrops
185 #define	if_noproto	if_data.ifi_noproto
186 #define	if_lastchange	if_data.ifi_lastchange
187 #define if_recvquota	if_data.ifi_recvquota
188 #define	if_xmitquota	if_data.ifi_xmitquota
189 #define if_rawoutput(if, m, sa) if_output(if, m, sa, (struct rtentry *)0)
190 
191 /* for compatibility with other BSDs */
192 #define	if_addrlist	if_addrhead
193 #define	if_list		if_link
194 
195 /*
196  * Bit values in if_ipending
197  */
198 #define	IFI_RECV	1	/* I want to receive */
199 #define	IFI_XMIT	2	/* I want to transmit */
200 
201 /*
202  * Output queues (ifp->if_snd) and slow device input queues (*ifp->if_slowq)
203  * are queues of messages stored on ifqueue structures
204  * (defined above).  Entries are added to and deleted from these structures
205  * by these macros, which should be called with ipl raised to splimp().
206  */
207 #define IF_LOCK(ifq)		mtx_lock(&(ifq)->ifq_mtx)
208 #define IF_UNLOCK(ifq)		mtx_unlock(&(ifq)->ifq_mtx)
209 #define	_IF_QFULL(ifq)		((ifq)->ifq_len >= (ifq)->ifq_maxlen)
210 #define	_IF_DROP(ifq)		((ifq)->ifq_drops++)
211 #define	_IF_QLEN(ifq)		((ifq)->ifq_len)
212 
213 #define	_IF_ENQUEUE(ifq, m) do { 				\
214 	(m)->m_nextpkt = NULL;					\
215 	if ((ifq)->ifq_tail == NULL) 				\
216 		(ifq)->ifq_head = m; 				\
217 	else 							\
218 		(ifq)->ifq_tail->m_nextpkt = m; 		\
219 	(ifq)->ifq_tail = m; 					\
220 	(ifq)->ifq_len++; 					\
221 } while (0)
222 
223 #define IF_ENQUEUE(ifq, m) do {					\
224 	IF_LOCK(ifq); 						\
225 	_IF_ENQUEUE(ifq, m); 					\
226 	IF_UNLOCK(ifq); 					\
227 } while (0)
228 
229 #define	_IF_PREPEND(ifq, m) do {				\
230 	(m)->m_nextpkt = (ifq)->ifq_head; 			\
231 	if ((ifq)->ifq_tail == NULL) 				\
232 		(ifq)->ifq_tail = (m); 				\
233 	(ifq)->ifq_head = (m); 					\
234 	(ifq)->ifq_len++; 					\
235 } while (0)
236 
237 #define IF_PREPEND(ifq, m) do {		 			\
238 	IF_LOCK(ifq); 						\
239 	_IF_PREPEND(ifq, m); 					\
240 	IF_UNLOCK(ifq); 					\
241 } while (0)
242 
243 #define	_IF_DEQUEUE(ifq, m) do { 				\
244 	(m) = (ifq)->ifq_head; 					\
245 	if (m) { 						\
246 		if (((ifq)->ifq_head = (m)->m_nextpkt) == 0) 	\
247 			(ifq)->ifq_tail = NULL; 		\
248 		(m)->m_nextpkt = NULL; 				\
249 		(ifq)->ifq_len--; 				\
250 	} 							\
251 } while (0)
252 
253 #define IF_DEQUEUE(ifq, m) do { 				\
254 	IF_LOCK(ifq); 						\
255 	_IF_DEQUEUE(ifq, m); 					\
256 	IF_UNLOCK(ifq); 					\
257 } while (0)
258 
259 #define IF_DRAIN(ifq) do { 					\
260 	struct mbuf *m; 					\
261 	IF_LOCK(ifq); 						\
262 	for (;;) { 						\
263 		_IF_DEQUEUE(ifq, m); 				\
264 		if (m == NULL) 					\
265 			break; 					\
266 		m_freem(m); 					\
267 	} 							\
268 	IF_UNLOCK(ifq); 					\
269 } while (0)
270 
271 #ifdef _KERNEL
272 #define	IF_HANDOFF(ifq, m, ifp)			if_handoff(ifq, m, ifp, 0)
273 #define	IF_HANDOFF_ADJ(ifq, m, ifp, adj)	if_handoff(ifq, m, ifp, adj)
274 
275 static __inline int
276 if_handoff(struct ifqueue *ifq, struct mbuf *m, struct ifnet *ifp, int adjust)
277 {
278 	int active = 0;
279 
280 	IF_LOCK(ifq);
281 	if (_IF_QFULL(ifq)) {
282 		_IF_DROP(ifq);
283 		IF_UNLOCK(ifq);
284 		m_freem(m);
285 		return (0);
286 	}
287 	if (ifp != NULL) {
288 		ifp->if_obytes += m->m_pkthdr.len + adjust;
289 		if (m->m_flags & M_MCAST)
290 			ifp->if_omcasts++;
291 		active = ifp->if_flags & IFF_OACTIVE;
292 	}
293 	_IF_ENQUEUE(ifq, m);
294 	IF_UNLOCK(ifq);
295 	if (ifp != NULL && !active) {
296 		if (ifp->if_mpsafe) {
297 			DROP_GIANT_NOSWITCH();
298 			(*ifp->if_start)(ifp);
299 			PICKUP_GIANT();
300 		} else {
301 			(*ifp->if_start)(ifp);
302 		}
303 	}
304 	return (1);
305 }
306 
307 /*
308  * 72 was chosen below because it is the size of a TCP/IP
309  * header (40) + the minimum mss (32).
310  */
311 #define	IF_MINMTU	72
312 #define	IF_MAXMTU	65535
313 
314 #endif /* _KERNEL */
315 
316 /*
317  * The ifaddr structure contains information about one address
318  * of an interface.  They are maintained by the different address families,
319  * are allocated and attached when an address is set, and are linked
320  * together so all addresses for an interface can be located.
321  */
322 struct ifaddr {
323 	struct	sockaddr *ifa_addr;	/* address of interface */
324 	struct	sockaddr *ifa_dstaddr;	/* other end of p-to-p link */
325 #define	ifa_broadaddr	ifa_dstaddr	/* broadcast address interface */
326 	struct	sockaddr *ifa_netmask;	/* used to determine subnet */
327 	struct	if_data if_data;	/* not all members are meaningful */
328 	struct	ifnet *ifa_ifp;		/* back-pointer to interface */
329 	TAILQ_ENTRY(ifaddr) ifa_link;	/* queue macro glue */
330 	void	(*ifa_rtrequest)	/* check or clean routes (+ or -)'d */
331 		__P((int, struct rtentry *, struct rt_addrinfo *));
332 	u_short	ifa_flags;		/* mostly rt_flags for cloning */
333 	u_int	ifa_refcnt;		/* references to this structure */
334 	int	ifa_metric;		/* cost of going out this interface */
335 #ifdef notdef
336 	struct	rtentry *ifa_rt;	/* XXXX for ROUTETOIF ????? */
337 #endif
338 	int (*ifa_claim_addr)		/* check if an addr goes to this if */
339 		__P((struct ifaddr *, struct sockaddr *));
340 
341 };
342 #define	IFA_ROUTE	RTF_UP		/* route installed */
343 
344 /* for compatibility with other BSDs */
345 #define	ifa_list	ifa_link
346 
347 /*
348  * The prefix structure contains information about one prefix
349  * of an interface.  They are maintained by the different address families,
350  * are allocated and attached when an prefix or an address is set,
351  * and are linked together so all prefixes for an interface can be located.
352  */
353 struct ifprefix {
354 	struct	sockaddr *ifpr_prefix;	/* prefix of interface */
355 	struct	ifnet *ifpr_ifp;	/* back-pointer to interface */
356 	TAILQ_ENTRY(ifprefix) ifpr_list; /* queue macro glue */
357 	u_char	ifpr_plen;		/* prefix length in bits */
358 	u_char	ifpr_type;		/* protocol dependent prefix type */
359 };
360 
361 /*
362  * Multicast address structure.  This is analogous to the ifaddr
363  * structure except that it keeps track of multicast addresses.
364  * Also, the reference count here is a count of requests for this
365  * address, not a count of pointers to this structure.
366  */
367 struct ifmultiaddr {
368 	TAILQ_ENTRY(ifmultiaddr) ifma_link; /* queue macro glue */
369 	struct	sockaddr *ifma_addr; 	/* address this membership is for */
370 	struct	sockaddr *ifma_lladdr;	/* link-layer translation, if any */
371 	struct	ifnet *ifma_ifp;	/* back-pointer to interface */
372 	u_int	ifma_refcount;		/* reference count */
373 	void	*ifma_protospec;	/* protocol-specific state, if any */
374 };
375 
376 #ifdef _KERNEL
377 #define	IFAFREE(ifa) \
378 	do { \
379 		if ((ifa)->ifa_refcnt <= 0) \
380 			ifafree(ifa); \
381 		else \
382 			(ifa)->ifa_refcnt--; \
383 	} while (0)
384 
385 struct ifindex_entry {
386 	struct 	ifnet *ife_ifnet;
387 	struct	ifaddr *ife_ifnet_addr;
388 	dev_t	ife_dev;
389 };
390 
391 #define ifnet_byindex(idx)	ifindex_table[(idx)].ife_ifnet
392 #define ifaddr_byindex(idx)	ifindex_table[(idx)].ife_ifnet_addr
393 #define ifdev_byindex(idx)	ifindex_table[(idx)].ife_dev
394 
395 extern	struct ifnethead ifnet;
396 extern	struct ifindex_entry *ifindex_table;
397 extern	int ifqmaxlen;
398 extern	struct ifnet *loif;	/* first loopback interface */
399 extern	int if_index;
400 
401 void	ether_ifattach __P((struct ifnet *, int));
402 void	ether_ifdetach __P((struct ifnet *, int));
403 void	ether_input __P((struct ifnet *, struct ether_header *, struct mbuf *));
404 void	ether_demux __P((struct ifnet *, struct ether_header *, struct mbuf *));
405 int	ether_output __P((struct ifnet *,
406 	   struct mbuf *, struct sockaddr *, struct rtentry *));
407 int	ether_output_frame __P((struct ifnet *, struct mbuf *));
408 int	ether_ioctl __P((struct ifnet *, int, caddr_t));
409 
410 int	if_addmulti __P((struct ifnet *, struct sockaddr *,
411 			 struct ifmultiaddr **));
412 int	if_allmulti __P((struct ifnet *, int));
413 void	if_attach __P((struct ifnet *));
414 int	if_delmulti __P((struct ifnet *, struct sockaddr *));
415 void	if_detach __P((struct ifnet *));
416 void	if_down __P((struct ifnet *));
417 void	if_route __P((struct ifnet *, int flag, int fam));
418 int	if_setlladdr __P((struct ifnet *, const u_char *, int));
419 void	if_unroute __P((struct ifnet *, int flag, int fam));
420 void	if_up __P((struct ifnet *));
421 /*void	ifinit __P((void));*/ /* declared in systm.h for main() */
422 int	ifioctl __P((struct socket *, u_long, caddr_t, struct thread *));
423 int	ifpromisc __P((struct ifnet *, int));
424 struct	ifnet *ifunit __P((const char *));
425 struct	ifnet *if_withname __P((struct sockaddr *));
426 
427 int	if_poll_recv_slow __P((struct ifnet *ifp, int *quotap));
428 void	if_poll_xmit_slow __P((struct ifnet *ifp, int *quotap));
429 void	if_poll_throttle __P((void));
430 void	if_poll_unthrottle __P((void *));
431 void	if_poll_init __P((void));
432 void	if_poll __P((void));
433 
434 struct	ifaddr *ifa_ifwithaddr __P((struct sockaddr *));
435 struct	ifaddr *ifa_ifwithdstaddr __P((struct sockaddr *));
436 struct	ifaddr *ifa_ifwithnet __P((struct sockaddr *));
437 struct	ifaddr *ifa_ifwithroute __P((int, struct sockaddr *,
438 					struct sockaddr *));
439 struct	ifaddr *ifaof_ifpforaddr __P((struct sockaddr *, struct ifnet *));
440 void	ifafree __P((struct ifaddr *));
441 
442 struct	ifmultiaddr *ifmaof_ifpforaddr __P((struct sockaddr *,
443 					    struct ifnet *));
444 int	if_simloop __P((struct ifnet *ifp, struct mbuf *m, int af, int hlen));
445 
446 void	if_clone_attach __P((struct if_clone *));
447 void	if_clone_detach __P((struct if_clone *));
448 
449 int	if_clone_create __P((char *, int));
450 int	if_clone_destroy __P((const char *));
451 
452 #define IF_LLADDR(ifp)							\
453     LLADDR((struct sockaddr_dl *) ifaddr_byindex((ifp)->if_index)->ifa_addr)
454 
455 #endif /* _KERNEL */
456 
457 #endif /* !_NET_IF_VAR_H_ */
458