xref: /freebsd/sys/net/if_var.h (revision 5521ff5a4d1929056e7ffc982fac3341ca54df7c)
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	proc;
71 struct	rtentry;
72 struct	socket;
73 struct	ether_header;
74 #endif
75 
76 #include <sys/queue.h>		/* get TAILQ macros */
77 
78 #ifdef _KERNEL
79 #include <sys/mbuf.h>
80 #include <sys/systm.h>		/* XXX */
81 #endif /* _KERNEL */
82 #include <sys/lock.h>		/* XXX */
83 #include <sys/mutex.h>		/* XXX */
84 
85 TAILQ_HEAD(ifnethead, ifnet);	/* we use TAILQs so that the order of */
86 TAILQ_HEAD(ifaddrhead, ifaddr);	/* instantiation is preserved in the list */
87 TAILQ_HEAD(ifprefixhead, ifprefix);
88 TAILQ_HEAD(ifmultihead, ifmultiaddr);
89 
90 /*
91  * Structure defining a queue for a network interface.
92  */
93 struct	ifqueue {
94 	struct	mbuf *ifq_head;
95 	struct	mbuf *ifq_tail;
96 	int	ifq_len;
97 	int	ifq_maxlen;
98 	int	ifq_drops;
99 	struct	mtx ifq_mtx;
100 };
101 
102 /*
103  * Structure defining a network interface.
104  *
105  * (Would like to call this struct ``if'', but C isn't PL/1.)
106  */
107 struct ifnet {
108 	void	*if_softc;		/* pointer to driver state */
109 	char	*if_name;		/* name, e.g. ``en'' or ``lo'' */
110 	TAILQ_ENTRY(ifnet) if_link; 	/* all struct ifnets are chained */
111 	struct	ifaddrhead if_addrhead;	/* linked list of addresses per if */
112         int	if_pcount;		/* number of promiscuous listeners */
113 	struct	bpf_if *if_bpf;		/* packet filter structure */
114 	u_short	if_index;		/* numeric abbreviation for this if  */
115 	short	if_unit;		/* sub-unit for lower level driver */
116 	short	if_timer;		/* time 'til if_watchdog called */
117 	short	if_flags;		/* up/down, broadcast, etc. */
118 	int	if_mpsafe;		/* XXX TEMPORARY */
119 	int	if_ipending;		/* interrupts pending */
120 	void	*if_linkmib;		/* link-type-specific MIB data */
121 	size_t	if_linkmiblen;		/* length of above data */
122 	struct	if_data if_data;
123 	struct	ifmultihead if_multiaddrs; /* multicast addresses configured */
124 	int	if_amcount;		/* number of all-multicast requests */
125 /* procedure handles */
126 	int	(*if_output)		/* output routine (enqueue) */
127 		__P((struct ifnet *, struct mbuf *, struct sockaddr *,
128 		     struct rtentry *));
129 	void	(*if_start)		/* initiate output routine */
130 		__P((struct ifnet *));
131 	int	(*if_done)		/* output complete routine */
132 		__P((struct ifnet *));	/* (XXX not used; fake prototype) */
133 	int	(*if_ioctl)		/* ioctl routine */
134 		__P((struct ifnet *, u_long, caddr_t));
135 	void	(*if_watchdog)		/* timer routine */
136 		__P((struct ifnet *));
137 	int	(*if_poll_recv)		/* polled receive routine */
138 		__P((struct ifnet *, int *));
139 	int	(*if_poll_xmit)		/* polled transmit routine */
140 		__P((struct ifnet *, int *));
141 	void	(*if_poll_intren)	/* polled interrupt reenable routine */
142 		__P((struct ifnet *));
143 	void	(*if_poll_slowinput)	/* input routine for slow devices */
144 		__P((struct ifnet *, struct mbuf *));
145 	void	(*if_init)		/* Init routine */
146 		__P((void *));
147 	int	(*if_resolvemulti)	/* validate/resolve multicast */
148 		__P((struct ifnet *, struct sockaddr **, struct sockaddr *));
149 	struct	ifqueue if_snd;		/* output queue */
150 	struct	ifqueue *if_poll_slowq;	/* input queue for slow devices */
151 	struct	ifprefixhead if_prefixhead; /* list of prefixes per if */
152 };
153 
154 typedef void if_init_f_t __P((void *));
155 
156 #define	if_mtu		if_data.ifi_mtu
157 #define	if_type		if_data.ifi_type
158 #define if_physical	if_data.ifi_physical
159 #define	if_addrlen	if_data.ifi_addrlen
160 #define	if_hdrlen	if_data.ifi_hdrlen
161 #define	if_metric	if_data.ifi_metric
162 #define	if_baudrate	if_data.ifi_baudrate
163 #define	if_hwassist	if_data.ifi_hwassist
164 #define	if_ipackets	if_data.ifi_ipackets
165 #define	if_ierrors	if_data.ifi_ierrors
166 #define	if_opackets	if_data.ifi_opackets
167 #define	if_oerrors	if_data.ifi_oerrors
168 #define	if_collisions	if_data.ifi_collisions
169 #define	if_ibytes	if_data.ifi_ibytes
170 #define	if_obytes	if_data.ifi_obytes
171 #define	if_imcasts	if_data.ifi_imcasts
172 #define	if_omcasts	if_data.ifi_omcasts
173 #define	if_iqdrops	if_data.ifi_iqdrops
174 #define	if_noproto	if_data.ifi_noproto
175 #define	if_lastchange	if_data.ifi_lastchange
176 #define if_recvquota	if_data.ifi_recvquota
177 #define	if_xmitquota	if_data.ifi_xmitquota
178 #define if_rawoutput(if, m, sa) if_output(if, m, sa, (struct rtentry *)0)
179 
180 /* for compatibility with other BSDs */
181 #define	if_addrlist	if_addrhead
182 #define	if_list		if_link
183 
184 /*
185  * Bit values in if_ipending
186  */
187 #define	IFI_RECV	1	/* I want to receive */
188 #define	IFI_XMIT	2	/* I want to transmit */
189 
190 /*
191  * Output queues (ifp->if_snd) and slow device input queues (*ifp->if_slowq)
192  * are queues of messages stored on ifqueue structures
193  * (defined above).  Entries are added to and deleted from these structures
194  * by these macros, which should be called with ipl raised to splimp().
195  */
196 #define IF_LOCK(ifq)		mtx_lock(&(ifq)->ifq_mtx)
197 #define IF_UNLOCK(ifq)		mtx_unlock(&(ifq)->ifq_mtx)
198 #define	_IF_QFULL(ifq)		((ifq)->ifq_len >= (ifq)->ifq_maxlen)
199 #define	_IF_DROP(ifq)		((ifq)->ifq_drops++)
200 #define	_IF_QLEN(ifq)		((ifq)->ifq_len)
201 
202 #define	_IF_ENQUEUE(ifq, m) do { 				\
203 	(m)->m_nextpkt = NULL;					\
204 	if ((ifq)->ifq_tail == NULL) 				\
205 		(ifq)->ifq_head = m; 				\
206 	else 							\
207 		(ifq)->ifq_tail->m_nextpkt = m; 		\
208 	(ifq)->ifq_tail = m; 					\
209 	(ifq)->ifq_len++; 					\
210 } while (0)
211 
212 #define IF_ENQUEUE(ifq, m) do {					\
213 	IF_LOCK(ifq); 						\
214 	_IF_ENQUEUE(ifq, m); 					\
215 	IF_UNLOCK(ifq); 					\
216 } while (0)
217 
218 #define	_IF_PREPEND(ifq, m) do {				\
219 	(m)->m_nextpkt = (ifq)->ifq_head; 			\
220 	if ((ifq)->ifq_tail == NULL) 				\
221 		(ifq)->ifq_tail = (m); 				\
222 	(ifq)->ifq_head = (m); 					\
223 	(ifq)->ifq_len++; 					\
224 } while (0)
225 
226 #define IF_PREPEND(ifq, m) do {		 			\
227 	IF_LOCK(ifq); 						\
228 	_IF_PREPEND(ifq, m); 					\
229 	IF_UNLOCK(ifq); 					\
230 } while (0)
231 
232 #define	_IF_DEQUEUE(ifq, m) do { 				\
233 	(m) = (ifq)->ifq_head; 					\
234 	if (m) { 						\
235 		if (((ifq)->ifq_head = (m)->m_nextpkt) == 0) 	\
236 			(ifq)->ifq_tail = NULL; 		\
237 		(m)->m_nextpkt = NULL; 				\
238 		(ifq)->ifq_len--; 				\
239 	} 							\
240 } while (0)
241 
242 #define IF_DEQUEUE(ifq, m) do { 				\
243 	IF_LOCK(ifq); 						\
244 	_IF_DEQUEUE(ifq, m); 					\
245 	IF_UNLOCK(ifq); 					\
246 } while (0)
247 
248 #define IF_DRAIN(ifq) do { 					\
249 	struct mbuf *m; 					\
250 	IF_LOCK(ifq); 						\
251 	for (;;) { 						\
252 		_IF_DEQUEUE(ifq, m); 				\
253 		if (m == NULL) 					\
254 			break; 					\
255 		m_freem(m); 					\
256 	} 							\
257 	IF_UNLOCK(ifq); 					\
258 } while (0)
259 
260 #ifdef _KERNEL
261 #define	IF_HANDOFF(ifq, m, ifp)			if_handoff(ifq, m, ifp, 0)
262 #define	IF_HANDOFF_ADJ(ifq, m, ifp, adj)	if_handoff(ifq, m, ifp, adj)
263 
264 static __inline int
265 if_handoff(struct ifqueue *ifq, struct mbuf *m, struct ifnet *ifp, int adjust)
266 {
267 	int active = 0;
268 
269 	IF_LOCK(ifq);
270 	if (_IF_QFULL(ifq)) {
271 		_IF_DROP(ifq);
272 		IF_UNLOCK(ifq);
273 		m_freem(m);
274 		return (0);
275 	}
276 	if (ifp != NULL) {
277 		ifp->if_obytes += m->m_pkthdr.len + adjust;
278 		if (m->m_flags & M_MCAST)
279 			ifp->if_omcasts++;
280 		active = ifp->if_flags & IFF_OACTIVE;
281 	}
282 	_IF_ENQUEUE(ifq, m);
283 	IF_UNLOCK(ifq);
284 	if (ifp != NULL && !active) {
285 		if (ifp->if_mpsafe) {
286 			DROP_GIANT_NOSWITCH();
287 			(*ifp->if_start)(ifp);
288 			PICKUP_GIANT();
289 		} else {
290 			(*ifp->if_start)(ifp);
291 		}
292 	}
293 	return (1);
294 }
295 
296 /*
297  * 72 was chosen below because it is the size of a TCP/IP
298  * header (40) + the minimum mss (32).
299  */
300 #define	IF_MINMTU	72
301 #define	IF_MAXMTU	65535
302 
303 #endif /* _KERNEL */
304 
305 /*
306  * The ifaddr structure contains information about one address
307  * of an interface.  They are maintained by the different address families,
308  * are allocated and attached when an address is set, and are linked
309  * together so all addresses for an interface can be located.
310  */
311 struct ifaddr {
312 	struct	sockaddr *ifa_addr;	/* address of interface */
313 	struct	sockaddr *ifa_dstaddr;	/* other end of p-to-p link */
314 #define	ifa_broadaddr	ifa_dstaddr	/* broadcast address interface */
315 	struct	sockaddr *ifa_netmask;	/* used to determine subnet */
316 	struct	if_data if_data;	/* not all members are meaningful */
317 	struct	ifnet *ifa_ifp;		/* back-pointer to interface */
318 	TAILQ_ENTRY(ifaddr) ifa_link;	/* queue macro glue */
319 	void	(*ifa_rtrequest)	/* check or clean routes (+ or -)'d */
320 		__P((int, struct rtentry *, struct sockaddr *));
321 	u_short	ifa_flags;		/* mostly rt_flags for cloning */
322 	u_int	ifa_refcnt;		/* references to this structure */
323 	int	ifa_metric;		/* cost of going out this interface */
324 #ifdef notdef
325 	struct	rtentry *ifa_rt;	/* XXXX for ROUTETOIF ????? */
326 #endif
327 	int (*ifa_claim_addr)		/* check if an addr goes to this if */
328 		__P((struct ifaddr *, struct sockaddr *));
329 
330 };
331 #define	IFA_ROUTE	RTF_UP		/* route installed */
332 
333 /* for compatibility with other BSDs */
334 #define	ifa_list	ifa_link
335 
336 /*
337  * The prefix structure contains information about one prefix
338  * of an interface.  They are maintained by the different address families,
339  * are allocated and attached when an prefix or an address is set,
340  * and are linked together so all prefixes for an interface can be located.
341  */
342 struct ifprefix {
343 	struct	sockaddr *ifpr_prefix;	/* prefix of interface */
344 	struct	ifnet *ifpr_ifp;	/* back-pointer to interface */
345 	TAILQ_ENTRY(ifprefix) ifpr_list; /* queue macro glue */
346 	u_char	ifpr_plen;		/* prefix length in bits */
347 	u_char	ifpr_type;		/* protocol dependent prefix type */
348 };
349 
350 /*
351  * Multicast address structure.  This is analogous to the ifaddr
352  * structure except that it keeps track of multicast addresses.
353  * Also, the reference count here is a count of requests for this
354  * address, not a count of pointers to this structure.
355  */
356 struct ifmultiaddr {
357 	TAILQ_ENTRY(ifmultiaddr) ifma_link; /* queue macro glue */
358 	struct	sockaddr *ifma_addr; 	/* address this membership is for */
359 	struct	sockaddr *ifma_lladdr;	/* link-layer translation, if any */
360 	struct	ifnet *ifma_ifp;	/* back-pointer to interface */
361 	u_int	ifma_refcount;		/* reference count */
362 	void	*ifma_protospec;	/* protocol-specific state, if any */
363 };
364 
365 #ifdef _KERNEL
366 #define	IFAFREE(ifa) \
367 	do { \
368 		if ((ifa)->ifa_refcnt <= 0) \
369 			ifafree(ifa); \
370 		else \
371 			(ifa)->ifa_refcnt--; \
372 	} while (0)
373 
374 extern	struct ifnethead ifnet;
375 extern struct	ifnet	**ifindex2ifnet;
376 extern	int ifqmaxlen;
377 extern	struct ifnet *loif;	/* first loopback interface */
378 extern	int if_index;
379 extern	struct ifaddr **ifnet_addrs;
380 
381 void	ether_ifattach __P((struct ifnet *, int));
382 void	ether_ifdetach __P((struct ifnet *, int));
383 void	ether_input __P((struct ifnet *, struct ether_header *, struct mbuf *));
384 void	ether_demux __P((struct ifnet *, struct ether_header *, struct mbuf *));
385 int	ether_output __P((struct ifnet *,
386 	   struct mbuf *, struct sockaddr *, struct rtentry *));
387 int	ether_output_frame __P((struct ifnet *, struct mbuf *));
388 int	ether_ioctl __P((struct ifnet *, int, caddr_t));
389 
390 int	if_addmulti __P((struct ifnet *, struct sockaddr *,
391 			 struct ifmultiaddr **));
392 int	if_allmulti __P((struct ifnet *, int));
393 void	if_attach __P((struct ifnet *));
394 int	if_delmulti __P((struct ifnet *, struct sockaddr *));
395 void	if_detach __P((struct ifnet *));
396 void	if_down __P((struct ifnet *));
397 void	if_route __P((struct ifnet *, int flag, int fam));
398 int	if_setlladdr __P((struct ifnet *, const u_char *, int));
399 void	if_unroute __P((struct ifnet *, int flag, int fam));
400 void	if_up __P((struct ifnet *));
401 /*void	ifinit __P((void));*/ /* declared in systm.h for main() */
402 int	ifioctl __P((struct socket *, u_long, caddr_t, struct proc *));
403 int	ifpromisc __P((struct ifnet *, int));
404 struct	ifnet *ifunit __P((const char *));
405 struct	ifnet *if_withname __P((struct sockaddr *));
406 
407 int	if_poll_recv_slow __P((struct ifnet *ifp, int *quotap));
408 void	if_poll_xmit_slow __P((struct ifnet *ifp, int *quotap));
409 void	if_poll_throttle __P((void));
410 void	if_poll_unthrottle __P((void *));
411 void	if_poll_init __P((void));
412 void	if_poll __P((void));
413 
414 struct	ifaddr *ifa_ifwithaddr __P((struct sockaddr *));
415 struct	ifaddr *ifa_ifwithdstaddr __P((struct sockaddr *));
416 struct	ifaddr *ifa_ifwithnet __P((struct sockaddr *));
417 struct	ifaddr *ifa_ifwithroute __P((int, struct sockaddr *,
418 					struct sockaddr *));
419 struct	ifaddr *ifaof_ifpforaddr __P((struct sockaddr *, struct ifnet *));
420 void	ifafree __P((struct ifaddr *));
421 
422 struct	ifmultiaddr *ifmaof_ifpforaddr __P((struct sockaddr *,
423 					    struct ifnet *));
424 int	if_simloop __P((struct ifnet *ifp, struct mbuf *m, int af, int hlen));
425 
426 void	if_clone_attach __P((struct if_clone *));
427 void	if_clone_detach __P((struct if_clone *));
428 
429 int	if_clone_create __P((char *, int));
430 int	if_clone_destroy __P((const char *));
431 
432 #endif /* _KERNEL */
433 
434 #endif /* !_NET_IF_VAR_H_ */
435