xref: /freebsd/sys/net/if_var.h (revision 5129159789cc9d7bc514e4546b88e3427695002d)
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 TAILQ_HEAD(ifnethead, ifnet);	/* we use TAILQs so that the order of */
79 TAILQ_HEAD(ifaddrhead, ifaddr);	/* instantiation is preserved in the list */
80 TAILQ_HEAD(ifprefixhead, ifprefix);
81 LIST_HEAD(ifmultihead, ifmultiaddr);
82 
83 /*
84  * Structure defining a queue for a network interface.
85  */
86 struct	ifqueue {
87 	struct	mbuf *ifq_head;
88 	struct	mbuf *ifq_tail;
89 	int	ifq_len;
90 	int	ifq_maxlen;
91 	int	ifq_drops;
92 };
93 
94 /*
95  * Structure defining a network interface.
96  *
97  * (Would like to call this struct ``if'', but C isn't PL/1.)
98  */
99 struct ifnet {
100 	void	*if_softc;		/* pointer to driver state */
101 	char	*if_name;		/* name, e.g. ``en'' or ``lo'' */
102 	TAILQ_ENTRY(ifnet) if_link; 	/* all struct ifnets are chained */
103 	struct	ifaddrhead if_addrhead;	/* linked list of addresses per if */
104         int	if_pcount;		/* number of promiscuous listeners */
105 	struct	bpf_if *if_bpf;		/* packet filter structure */
106 	u_short	if_index;		/* numeric abbreviation for this if  */
107 	short	if_unit;		/* sub-unit for lower level driver */
108 	short	if_timer;		/* time 'til if_watchdog called */
109 	short	if_flags;		/* up/down, broadcast, etc. */
110 	int	if_ipending;		/* interrupts pending */
111 	void	*if_linkmib;		/* link-type-specific MIB data */
112 	size_t	if_linkmiblen;		/* length of above data */
113 	struct	if_data if_data;
114 	struct	ifmultihead if_multiaddrs; /* multicast addresses configured */
115 	int	if_amcount;		/* number of all-multicast requests */
116 /* procedure handles */
117 	int	(*if_output)		/* output routine (enqueue) */
118 		__P((struct ifnet *, struct mbuf *, struct sockaddr *,
119 		     struct rtentry *));
120 	void	(*if_start)		/* initiate output routine */
121 		__P((struct ifnet *));
122 	int	(*if_done)		/* output complete routine */
123 		__P((struct ifnet *));	/* (XXX not used; fake prototype) */
124 	int	(*if_ioctl)		/* ioctl routine */
125 		__P((struct ifnet *, u_long, caddr_t));
126 	void	(*if_watchdog)		/* timer routine */
127 		__P((struct ifnet *));
128 	int	(*if_poll_recv)		/* polled receive routine */
129 		__P((struct ifnet *, int *));
130 	int	(*if_poll_xmit)		/* polled transmit routine */
131 		__P((struct ifnet *, int *));
132 	void	(*if_poll_intren)	/* polled interrupt reenable routine */
133 		__P((struct ifnet *));
134 	void	(*if_poll_slowinput)	/* input routine for slow devices */
135 		__P((struct ifnet *, struct mbuf *));
136 	void	(*if_init)		/* Init routine */
137 		__P((void *));
138 	int	(*if_resolvemulti)	/* validate/resolve multicast */
139 		__P((struct ifnet *, struct sockaddr **, struct sockaddr *));
140 	struct	ifqueue if_snd;		/* output queue */
141 	struct	ifqueue *if_poll_slowq;	/* input queue for slow devices */
142 	struct	ifprefixhead if_prefixhead; /* list of prefixes per if */
143 };
144 typedef void if_init_f_t __P((void *));
145 
146 #define	if_mtu		if_data.ifi_mtu
147 #define	if_type		if_data.ifi_type
148 #define if_physical	if_data.ifi_physical
149 #define	if_addrlen	if_data.ifi_addrlen
150 #define	if_hdrlen	if_data.ifi_hdrlen
151 #define	if_metric	if_data.ifi_metric
152 #define	if_baudrate	if_data.ifi_baudrate
153 #define	if_ipackets	if_data.ifi_ipackets
154 #define	if_ierrors	if_data.ifi_ierrors
155 #define	if_opackets	if_data.ifi_opackets
156 #define	if_oerrors	if_data.ifi_oerrors
157 #define	if_collisions	if_data.ifi_collisions
158 #define	if_ibytes	if_data.ifi_ibytes
159 #define	if_obytes	if_data.ifi_obytes
160 #define	if_imcasts	if_data.ifi_imcasts
161 #define	if_omcasts	if_data.ifi_omcasts
162 #define	if_iqdrops	if_data.ifi_iqdrops
163 #define	if_noproto	if_data.ifi_noproto
164 #define	if_lastchange	if_data.ifi_lastchange
165 #define if_recvquota	if_data.ifi_recvquota
166 #define	if_xmitquota	if_data.ifi_xmitquota
167 #define if_rawoutput(if, m, sa) if_output(if, m, sa, (struct rtentry *)0)
168 
169 /* for compatibility with other BSDs */
170 #define	if_addrlist	if_addrhead
171 #define	if_list		if_link
172 
173 /*
174  * Bit values in if_ipending
175  */
176 #define	IFI_RECV	1	/* I want to receive */
177 #define	IFI_XMIT	2	/* I want to transmit */
178 
179 /*
180  * Output queues (ifp->if_snd) and slow device input queues (*ifp->if_slowq)
181  * are queues of messages stored on ifqueue structures
182  * (defined above).  Entries are added to and deleted from these structures
183  * by these macros, which should be called with ipl raised to splimp().
184  */
185 #define	IF_QFULL(ifq)		((ifq)->ifq_len >= (ifq)->ifq_maxlen)
186 #define	IF_DROP(ifq)		((ifq)->ifq_drops++)
187 #define	IF_ENQUEUE(ifq, m) { \
188 	(m)->m_nextpkt = 0; \
189 	if ((ifq)->ifq_tail == 0) \
190 		(ifq)->ifq_head = m; \
191 	else \
192 		(ifq)->ifq_tail->m_nextpkt = m; \
193 	(ifq)->ifq_tail = m; \
194 	(ifq)->ifq_len++; \
195 }
196 #define	IF_PREPEND(ifq, m) { \
197 	(m)->m_nextpkt = (ifq)->ifq_head; \
198 	if ((ifq)->ifq_tail == 0) \
199 		(ifq)->ifq_tail = (m); \
200 	(ifq)->ifq_head = (m); \
201 	(ifq)->ifq_len++; \
202 }
203 #define	IF_DEQUEUE(ifq, m) { \
204 	(m) = (ifq)->ifq_head; \
205 	if (m) { \
206 		if (((ifq)->ifq_head = (m)->m_nextpkt) == 0) \
207 			(ifq)->ifq_tail = 0; \
208 		(m)->m_nextpkt = 0; \
209 		(ifq)->ifq_len--; \
210 	} \
211 }
212 
213 #ifdef KERNEL
214 #define	IF_ENQ_DROP(ifq, m)	if_enq_drop(ifq, m)
215 
216 #if defined(__GNUC__) && defined(MT_HEADER)
217 static __inline int
218 if_queue_drop(struct ifqueue *ifq, struct mbuf *m)
219 {
220 	IF_DROP(ifq);
221 	return 0;
222 }
223 
224 static __inline int
225 if_enq_drop(struct ifqueue *ifq, struct mbuf *m)
226 {
227 	if (IF_QFULL(ifq) &&
228 	    !if_queue_drop(ifq, m))
229 		return 0;
230 	IF_ENQUEUE(ifq, m);
231 	return 1;
232 }
233 #else
234 
235 #ifdef MT_HEADER
236 int	if_enq_drop __P((struct ifqueue *, struct mbuf *));
237 #endif
238 
239 #endif
240 
241 /*
242  * 72 was chosen below because it is the size of a TCP/IP
243  * header (40) + the minimum mss (32).
244  */
245 #define	IF_MINMTU	72
246 #define	IF_MAXMTU	65535
247 
248 #endif /* KERNEL */
249 
250 /*
251  * The ifaddr structure contains information about one address
252  * of an interface.  They are maintained by the different address families,
253  * are allocated and attached when an address is set, and are linked
254  * together so all addresses for an interface can be located.
255  */
256 struct ifaddr {
257 	struct	sockaddr *ifa_addr;	/* address of interface */
258 	struct	sockaddr *ifa_dstaddr;	/* other end of p-to-p link */
259 #define	ifa_broadaddr	ifa_dstaddr	/* broadcast address interface */
260 	struct	sockaddr *ifa_netmask;	/* used to determine subnet */
261 	struct	ifnet *ifa_ifp;		/* back-pointer to interface */
262 	TAILQ_ENTRY(ifaddr) ifa_link;	/* queue macro glue */
263 	void	(*ifa_rtrequest)	/* check or clean routes (+ or -)'d */
264 		__P((int, struct rtentry *, struct sockaddr *));
265 	u_short	ifa_flags;		/* mostly rt_flags for cloning */
266 	u_int	ifa_refcnt;		/* references to this structure */
267 	int	ifa_metric;		/* cost of going out this interface */
268 #ifdef notdef
269 	struct	rtentry *ifa_rt;	/* XXXX for ROUTETOIF ????? */
270 #endif
271 	int (*ifa_claim_addr)		/* check if an addr goes to this if */
272 		__P((struct ifaddr *, struct sockaddr *));
273 
274 };
275 #define	IFA_ROUTE	RTF_UP		/* route installed */
276 
277 /* for compatibility with other BSDs */
278 #define	ifa_list	ifa_link
279 
280 /*
281  * The prefix structure contains information about one prefix
282  * of an interface.  They are maintained by the different address families,
283  * are allocated and attached when an prefix or an address is set,
284  * and are linked together so all prefixes for an interface can be located.
285  */
286 struct ifprefix {
287 	struct	sockaddr *ifpr_prefix;	/* prefix of interface */
288 	struct	ifnet *ifpr_ifp;	/* back-pointer to interface */
289 	TAILQ_ENTRY(ifprefix) ifpr_list; /* queue macro glue */
290 	u_char	ifpr_plen;		/* prefix length in bits */
291 	u_char	ifpr_type;		/* protocol dependent prefix type */
292 };
293 
294 /*
295  * Multicast address structure.  This is analogous to the ifaddr
296  * structure except that it keeps track of multicast addresses.
297  * Also, the reference count here is a count of requests for this
298  * address, not a count of pointers to this structure.
299  */
300 struct ifmultiaddr {
301 	LIST_ENTRY(ifmultiaddr) ifma_link; /* queue macro glue */
302 	struct	sockaddr *ifma_addr; 	/* address this membership is for */
303 	struct	sockaddr *ifma_lladdr;	/* link-layer translation, if any */
304 	struct	ifnet *ifma_ifp;	/* back-pointer to interface */
305 	u_int	ifma_refcount;		/* reference count */
306 	void	*ifma_protospec;	/* protocol-specific state, if any */
307 };
308 
309 #ifdef KERNEL
310 #define	IFAFREE(ifa) \
311 	do { \
312 		if ((ifa)->ifa_refcnt <= 0) \
313 			ifafree(ifa); \
314 		else \
315 			(ifa)->ifa_refcnt--; \
316 	} while (0)
317 
318 extern	struct ifnethead ifnet;
319 extern struct	ifnet	**ifindex2ifnet;
320 extern	int ifqmaxlen;
321 extern	struct ifnet loif[];
322 extern	int if_index;
323 extern	struct ifaddr **ifnet_addrs;
324 
325 void	ether_ifattach __P((struct ifnet *));
326 void	ether_input __P((struct ifnet *, struct ether_header *, struct mbuf *));
327 int	ether_output __P((struct ifnet *,
328 	   struct mbuf *, struct sockaddr *, struct rtentry *));
329 int	ether_ioctl __P((struct ifnet *, int, caddr_t));
330 
331 int	if_addmulti __P((struct ifnet *, struct sockaddr *,
332 			 struct ifmultiaddr **));
333 int	if_allmulti __P((struct ifnet *, int));
334 void	if_attach __P((struct ifnet *));
335 int	if_delmulti __P((struct ifnet *, struct sockaddr *));
336 void	if_detach __P((struct ifnet *));
337 void	if_down __P((struct ifnet *));
338 void	if_route __P((struct ifnet *, int flag, int fam));
339 void	if_unroute __P((struct ifnet *, int flag, int fam));
340 void	if_up __P((struct ifnet *));
341 /*void	ifinit __P((void));*/ /* declared in systm.h for main() */
342 int	ifioctl __P((struct socket *, u_long, caddr_t, struct proc *));
343 int	ifpromisc __P((struct ifnet *, int));
344 struct	ifnet *ifunit __P((char *));
345 struct	ifnet *if_withname __P((struct sockaddr *));
346 
347 int	if_poll_recv_slow __P((struct ifnet *ifp, int *quotap));
348 void	if_poll_xmit_slow __P((struct ifnet *ifp, int *quotap));
349 void	if_poll_throttle __P((void));
350 void	if_poll_unthrottle __P((void *));
351 void	if_poll_init __P((void));
352 void	if_poll __P((void));
353 
354 struct	ifaddr *ifa_ifwithaddr __P((struct sockaddr *));
355 struct	ifaddr *ifa_ifwithdstaddr __P((struct sockaddr *));
356 struct	ifaddr *ifa_ifwithnet __P((struct sockaddr *));
357 struct	ifaddr *ifa_ifwithroute __P((int, struct sockaddr *,
358 					struct sockaddr *));
359 struct	ifaddr *ifaof_ifpforaddr __P((struct sockaddr *, struct ifnet *));
360 void	ifafree __P((struct ifaddr *));
361 
362 struct	ifmultiaddr *ifmaof_ifpforaddr __P((struct sockaddr *,
363 					    struct ifnet *));
364 int	if_simloop __P((struct ifnet *ifp, struct mbuf *m,
365 		struct sockaddr *dst, int hlen));
366 
367 #endif /* KERNEL */
368 
369 
370 #endif /* !_NET_IF_VAR_H_ */
371