xref: /dflybsd-src/sys/net/if_var.h (revision 1f0f7b357f695364c2d426fad5891e5b0177d56a)
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: src/sys/net/if_var.h,v 1.18.2.16 2003/04/15 18:11:19 fjoe Exp $
35  * $DragonFly: src/sys/net/if_var.h,v 1.31 2005/10/24 08:06:16 sephe Exp $
36  */
37 
38 #ifndef	_NET_IF_VAR_H_
39 #define	_NET_IF_VAR_H_
40 
41 /*
42  * Structures defining a network interface, providing a packet
43  * transport mechanism (ala level 0 of the PUP protocols).
44  *
45  * Each interface accepts output datagrams of a specified maximum
46  * length, and provides higher level routines with input datagrams
47  * received from its medium.
48  *
49  * Output occurs when the routine if_output is called, with three parameters:
50  *	(*ifp->if_output)(ifp, m, dst, rt)
51  * Here m is the mbuf chain to be sent and dst is the destination address.
52  * The output routine encapsulates the supplied datagram if necessary,
53  * and then transmits it on its medium.
54  *
55  * On input, each interface unwraps the data received by it, and either
56  * places it on the input queue of a internetwork datagram routine
57  * and posts the associated software interrupt, or passes the datagram to
58  * the routine if_input. It is called with the mbuf chain as parameter:
59  *	(*ifp->if_input)(ifp, m)
60  * The input routine removes the protocol dependent header if necessary.
61  *
62  * Routines exist for locating interfaces by their addresses
63  * or for locating a interface on a certain network, as well as more general
64  * routing and gateway routines maintaining information used to locate
65  * interfaces.  These routines live in the files if.c and route.c
66  */
67 
68 /*
69  * Forward structure declarations for function prototypes [sic].
70  */
71 struct	mbuf;
72 struct	proc;
73 struct	rtentry;
74 struct	rt_addrinfo;
75 struct	socket;
76 struct	ether_header;
77 struct	ucred;
78 
79 #include <sys/queue.h>		/* get TAILQ macros */
80 
81 #include <net/altq/if_altq.h>
82 
83 #ifdef _KERNEL
84 #include <sys/eventhandler.h>
85 #include <sys/mbuf.h>
86 #include <sys/systm.h>		/* XXX */
87 #include <sys/thread2.h>
88 #endif /* _KERNEL */
89 
90 #define IF_DUNIT_NONE   -1
91 
92 TAILQ_HEAD(ifnethead, ifnet);	/* we use TAILQs so that the order of */
93 TAILQ_HEAD(ifaddrhead, ifaddr);	/* instantiation is preserved in the list */
94 TAILQ_HEAD(ifprefixhead, ifprefix);
95 LIST_HEAD(ifmultihead, ifmultiaddr);
96 
97 /*
98  * Structure defining a queue for a network interface.
99  */
100 struct	ifqueue {
101 	struct	mbuf *ifq_head;
102 	struct	mbuf *ifq_tail;
103 	int	ifq_len;
104 	int	ifq_maxlen;
105 	int	ifq_drops;
106 };
107 
108 /*
109  * Note of DEVICE_POLLING
110  * 1) Any file(*.c) that depends on DEVICE_POLLING supports in this
111  *    file should include opt_polling.h at its beginning.
112  * 2) When struct changes, which are conditioned by DEVICE_POLLING,
113  *    are to be introduced, please keep the struct's size and layout
114  *    same, no matter whether DEVICE_POLLING is defined or not.
115  *    See ifnet.if_poll and ifnet.if_poll_unused for example.
116  */
117 
118 #ifdef DEVICE_POLLING
119 enum poll_cmd { POLL_ONLY, POLL_AND_CHECK_STATUS, POLL_DEREGISTER,
120 		POLL_REGISTER };
121 #endif
122 
123 /*
124  * Structure defining a network interface.
125  *
126  * (Would like to call this struct ``if'', but C isn't PL/1.)
127  */
128 
129 /*
130  * NB: For FreeBSD, it is assumed that each NIC driver's softc starts with
131  * one of these structures, typically held within an arpcom structure.
132  *
133  *	struct <foo>_softc {
134  *		struct arpcom {
135  *			struct  ifnet ac_if;
136  *			...
137  *		} <arpcom> ;
138  *		...
139  *	};
140  *
141  * The assumption is used in a number of places, including many
142  * files in sys/net, device drivers, and sys/dev/mii.c:miibus_attach().
143  *
144  * Unfortunately devices' softc are opaque, so we depend on this layout
145  * to locate the struct ifnet from the softc in the generic code.
146  *
147  * Note that not all fields are used by drivers in the FreeBSD source
148  * tree. However, who knows what third party software does with fields
149  * marked as "unused", such as if_ipending, if_done, and if_poll*,
150  * so any attemt to redefine their meaning might end up in binary
151  * compatibility problems, even if the size of struct ifnet, and
152  * the size and position of its fields do not change.
153  * We just have to live with that.
154  */
155 struct ifnet {
156 	void	*if_softc;		/* pointer to driver state */
157 	TAILQ_ENTRY(ifnet) if_link;	/* all struct ifnets are chained */
158 	char	if_xname[IFNAMSIZ];	/* external name (name + unit) */
159 	const char *if_dname;		/* driver name */
160 	int	if_dunit;		/* unit or IF_DUNIT_NONE */
161 	struct	ifaddrhead if_addrhead;	/* linked list of addresses per if */
162 	int	if_pcount;		/* number of promiscuous listeners */
163 	struct	bpf_if *if_bpf;		/* packet filter structure */
164 	u_short	if_index;		/* numeric abbreviation for this if  */
165 	short	if_timer;		/* time 'til if_watchdog called */
166 	int	if_flags;		/* up/down, broadcast, etc. */
167 	int	if_capabilities;	/* interface capabilities */
168 	int	if_capenable;		/* enabled features */
169 	void	*if_linkmib;		/* link-type-specific MIB data */
170 	size_t	if_linkmiblen;		/* length of above data */
171 	struct	if_data if_data;
172 	struct	ifmultihead if_multiaddrs; /* multicast addresses configured */
173 	int	if_amcount;		/* number of all-multicast requests */
174 /* procedure handles */
175 	int	(*if_output)		/* output routine (enqueue) */
176 		(struct ifnet *, struct mbuf *, struct sockaddr *,
177 		     struct rtentry *);
178 	void	(*if_input)		/* input routine from hardware driver */
179 		(struct ifnet *, struct mbuf *);
180 	void	(*if_start)		/* initiate output routine */
181 		(struct ifnet *);
182 	int	(*if_ioctl)		/* ioctl routine */
183 		(struct ifnet *, u_long, caddr_t, struct ucred *);
184 	void	(*if_watchdog)		/* timer routine */
185 		(struct ifnet *);
186 	void	(*if_init)		/* Init routine */
187 		(void *);
188 	int	(*if_resolvemulti)	/* validate/resolve multicast */
189 		(struct ifnet *, struct sockaddr **, struct sockaddr *);
190 #ifdef DEVICE_POLLING
191 	void	(*if_poll)		/* IFF_POLLING support */
192 		(struct ifnet *, enum poll_cmd, int);
193 #else
194 	void	(*if_poll_unused)(void); /* placeholder */
195 #endif
196 	struct	ifaltq if_snd;		/* output queue (includes altq) */
197 	struct	ifprefixhead if_prefixhead; /* list of prefixes per if */
198 	const uint8_t	*if_broadcastaddr;
199 	void	*if_afdata[AF_MAX];
200 	struct ifaddr	*if_lladdr;
201 };
202 typedef void if_init_f_t (void *);
203 
204 #define	if_mtu		if_data.ifi_mtu
205 #define	if_type		if_data.ifi_type
206 #define if_physical	if_data.ifi_physical
207 #define	if_addrlen	if_data.ifi_addrlen
208 #define	if_hdrlen	if_data.ifi_hdrlen
209 #define	if_metric	if_data.ifi_metric
210 #define	if_baudrate	if_data.ifi_baudrate
211 #define	if_hwassist	if_data.ifi_hwassist
212 #define	if_ipackets	if_data.ifi_ipackets
213 #define	if_ierrors	if_data.ifi_ierrors
214 #define	if_opackets	if_data.ifi_opackets
215 #define	if_oerrors	if_data.ifi_oerrors
216 #define	if_collisions	if_data.ifi_collisions
217 #define	if_ibytes	if_data.ifi_ibytes
218 #define	if_obytes	if_data.ifi_obytes
219 #define	if_imcasts	if_data.ifi_imcasts
220 #define	if_omcasts	if_data.ifi_omcasts
221 #define	if_iqdrops	if_data.ifi_iqdrops
222 #define	if_noproto	if_data.ifi_noproto
223 #define	if_lastchange	if_data.ifi_lastchange
224 #define if_recvquota	if_data.ifi_recvquota
225 #define	if_xmitquota	if_data.ifi_xmitquota
226 #define if_rawoutput(if, m, sa) if_output(if, m, sa, (struct rtentry *)0)
227 
228 /* for compatibility with other BSDs */
229 #define	if_addrlist	if_addrhead
230 #define	if_list		if_link
231 
232 /*
233  * Output queues (ifp->if_snd) and slow device input queues (*ifp->if_slowq)
234  * are queues of messages stored on ifqueue structures
235  * (defined above).  Entries are added to and deleted from these structures
236  * by these macros, which should be called with ipl raised to splimp().
237  */
238 #define	IF_QFULL(ifq)		((ifq)->ifq_len >= (ifq)->ifq_maxlen)
239 #define	IF_DROP(ifq)		((ifq)->ifq_drops++)
240 #define	IF_QLEN(ifq)		((ifq)->ifq_len)
241 #define	IF_QEMPTY(ifq)		(IF_QLEN(ifq) == 0)
242 #define	IF_ENQUEUE(ifq, m) { \
243 	(m)->m_nextpkt = 0; \
244 	if ((ifq)->ifq_tail == 0) \
245 		(ifq)->ifq_head = m; \
246 	else \
247 		(ifq)->ifq_tail->m_nextpkt = m; \
248 	(ifq)->ifq_tail = m; \
249 	(ifq)->ifq_len++; \
250 }
251 #define	IF_PREPEND(ifq, m) { \
252 	(m)->m_nextpkt = (ifq)->ifq_head; \
253 	if ((ifq)->ifq_tail == 0) \
254 		(ifq)->ifq_tail = (m); \
255 	(ifq)->ifq_head = (m); \
256 	(ifq)->ifq_len++; \
257 }
258 #define	IF_DEQUEUE(ifq, m) { \
259 	(m) = (ifq)->ifq_head; \
260 	if (m) { \
261 		if (((ifq)->ifq_head = (m)->m_nextpkt) == 0) \
262 			(ifq)->ifq_tail = 0; \
263 		(m)->m_nextpkt = 0; \
264 		(ifq)->ifq_len--; \
265 	} \
266 }
267 
268 #define	IF_POLL(ifq, m)		((m) = (ifq)->ifq_head)
269 
270 #define IF_DRAIN(ifq) do {						\
271 	struct mbuf *m;							\
272 	while (1) {							\
273 		IF_DEQUEUE(ifq, m);					\
274 		if (m == NULL)						\
275 			break;						\
276 		m_freem(m);						\
277 	}								\
278 } while (0)
279 
280 #ifdef _KERNEL
281 
282 #define IF_HANDOFF(ifq, m, ifp)			if_handoff(ifq, m, ifp, 0)
283 #define IF_HANDOFF_ADJ(ifq, m, ifp, adj)	if_handoff(ifq, m, ifp, adj)
284 
285 static __inline int
286 if_handoff(struct ifqueue *_ifq, struct mbuf *_m, struct ifnet *_ifp,
287 	   int _adjust)
288 {
289 	int _need_if_start = 0;
290 
291 	crit_enter();
292 
293 	if (IF_QFULL(_ifq)) {
294 		IF_DROP(_ifq);
295 		crit_exit();
296 		m_freem(_m);
297 		return (0);
298 	}
299 	if (_ifp != NULL) {
300 		_ifp->if_obytes += _m->m_pkthdr.len + _adjust;
301 		if (_m->m_flags & M_MCAST)
302 			_ifp->if_omcasts++;
303 		_need_if_start = !(_ifp->if_flags & IFF_OACTIVE);
304 	}
305 	IF_ENQUEUE(_ifq, _m);
306 	if (_need_if_start)
307 		(*_ifp->if_start)(_ifp);
308 	crit_exit();
309 	return (1);
310 }
311 
312 /*
313  * 72 was chosen below because it is the size of a TCP/IP
314  * header (40) + the minimum mss (32).
315  */
316 #define	IF_MINMTU	72
317 #define	IF_MAXMTU	65535
318 
319 #endif /* _KERNEL */
320 
321 /*
322  * The ifaddr structure contains information about one address
323  * of an interface.  They are maintained by the different address families,
324  * are allocated and attached when an address is set, and are linked
325  * together so all addresses for an interface can be located.
326  */
327 struct ifaddr {
328 	struct	sockaddr *ifa_addr;	/* address of interface */
329 	struct	sockaddr *ifa_dstaddr;	/* other end of p-to-p link */
330 #define	ifa_broadaddr	ifa_dstaddr	/* broadcast address interface */
331 	struct	sockaddr *ifa_netmask;	/* used to determine subnet */
332 	struct	if_data if_data;	/* not all members are meaningful */
333 	struct	ifnet *ifa_ifp;		/* back-pointer to interface */
334 	TAILQ_ENTRY(ifaddr) ifa_link;	/* queue macro glue */
335 	void	(*ifa_rtrequest)	/* check or clean routes (+ or -)'d */
336 		(int, struct rtentry *, struct rt_addrinfo *);
337 	u_short	ifa_flags;		/* mostly rt_flags for cloning */
338 	u_int	ifa_refcnt;		/* references to this structure */
339 	int	ifa_metric;		/* cost of going out this interface */
340 #ifdef notdef
341 	struct	rtentry *ifa_rt;	/* XXXX for ROUTETOIF ????? */
342 #endif
343 	int (*ifa_claim_addr)		/* check if an addr goes to this if */
344 		(struct ifaddr *, struct sockaddr *);
345 
346 };
347 #define	IFA_ROUTE	RTF_UP		/* route installed */
348 
349 /* for compatibility with other BSDs */
350 #define	ifa_list	ifa_link
351 
352 /*
353  * The prefix structure contains information about one prefix
354  * of an interface.  They are maintained by the different address families,
355  * are allocated and attached when an prefix or an address is set,
356  * and are linked together so all prefixes for an interface can be located.
357  */
358 struct ifprefix {
359 	struct	sockaddr *ifpr_prefix;	/* prefix of interface */
360 	struct	ifnet *ifpr_ifp;	/* back-pointer to interface */
361 	TAILQ_ENTRY(ifprefix) ifpr_list; /* queue macro glue */
362 	u_char	ifpr_plen;		/* prefix length in bits */
363 	u_char	ifpr_type;		/* protocol dependent prefix type */
364 };
365 
366 /*
367  * Multicast address structure.  This is analogous to the ifaddr
368  * structure except that it keeps track of multicast addresses.
369  * Also, the reference count here is a count of requests for this
370  * address, not a count of pointers to this structure.
371  */
372 struct ifmultiaddr {
373 	LIST_ENTRY(ifmultiaddr) ifma_link; /* queue macro glue */
374 	struct	sockaddr *ifma_addr;	/* address this membership is for */
375 	struct	sockaddr *ifma_lladdr;	/* link-layer translation, if any */
376 	struct	ifnet *ifma_ifp;	/* back-pointer to interface */
377 	u_int	ifma_refcount;		/* reference count */
378 	void	*ifma_protospec;	/* protocol-specific state, if any */
379 };
380 
381 #ifdef _KERNEL
382 /* interface address change event */
383 typedef void (*ifaddr_event_handler_t)(void *, struct ifnet *);
384 EVENTHANDLER_DECLARE(ifaddr_event, ifaddr_event_handler_t);
385 /* new interface attach event */
386 typedef void (*ifnet_attach_event_handler_t)(void *, struct ifnet *);
387 EVENTHANDLER_DECLARE(ifnet_attach_event, ifnet_attach_event_handler_t);
388 /* interface detach event */
389 typedef void (*ifnet_detach_event_handler_t)(void *, struct ifnet *);
390 EVENTHANDLER_DECLARE(ifnet_detach_event, ifnet_detach_event_handler_t);
391 /* interface clone event */
392 typedef void (*if_clone_event_handler_t)(void *, struct if_clone *);
393 EVENTHANDLER_DECLARE(if_clone_event, if_clone_event_handler_t);
394 
395 static __inline void
396 IFAREF(struct ifaddr *_ifa)
397 {
398 	++_ifa->ifa_refcnt;
399 }
400 
401 #include <sys/malloc.h>
402 
403 MALLOC_DECLARE(M_IFADDR);
404 MALLOC_DECLARE(M_IFMADDR);
405 
406 static __inline void
407 IFAFREE(struct ifaddr *_ifa)
408 {
409 	if (_ifa->ifa_refcnt <= 0)
410 		free(_ifa, M_IFADDR);
411 	else
412 		_ifa->ifa_refcnt--;
413 }
414 
415 extern	struct ifnethead ifnet;
416 extern struct	ifnet	**ifindex2ifnet;
417 extern	int ifqmaxlen;
418 extern	struct ifnet loif[];
419 extern	int if_index;
420 
421 void	ether_ifattach(struct ifnet *, uint8_t *);
422 void	ether_ifattach_bpf(struct ifnet *, uint8_t *, u_int, u_int);
423 void	ether_ifdetach(struct ifnet *);
424 void	ether_input(struct ifnet *, struct ether_header *, struct mbuf *);
425 void	ether_demux(struct ifnet *, struct ether_header *, struct mbuf *);
426 int	ether_output_frame(struct ifnet *, struct mbuf *);
427 int	ether_ioctl(struct ifnet *, int, caddr_t);
428 uint32_t	ether_crc32_le(const uint8_t *, size_t);
429 uint32_t	ether_crc32_be(const uint8_t *, size_t);
430 
431 int	if_addmulti(struct ifnet *, struct sockaddr *, struct ifmultiaddr **);
432 int	if_allmulti(struct ifnet *, int);
433 void	if_attach(struct ifnet *);
434 int	if_delmulti(struct ifnet *, struct sockaddr *);
435 void	if_detach(struct ifnet *);
436 void	if_down(struct ifnet *);
437 void	if_initname(struct ifnet *, const char *, int);
438 int	if_printf(struct ifnet *, const char *, ...) __printflike(2, 3);
439 void	if_route(struct ifnet *, int flag, int fam);
440 int	if_setlladdr(struct ifnet *, const u_char *, int);
441 void	if_unroute(struct ifnet *, int flag, int fam);
442 void	if_up(struct ifnet *);
443 /*void	ifinit(void);*/ /* declared in systm.h for main() */
444 int	ifioctl(struct socket *, u_long, caddr_t, struct thread *);
445 int	ifpromisc(struct ifnet *, int);
446 struct	ifnet *ifunit(const char *);
447 struct	ifnet *if_withname(struct sockaddr *);
448 
449 struct	ifaddr *ifa_ifwithaddr(struct sockaddr *);
450 struct	ifaddr *ifa_ifwithdstaddr(struct sockaddr *);
451 struct	ifaddr *ifa_ifwithnet(struct sockaddr *);
452 struct	ifaddr *ifa_ifwithroute(int, struct sockaddr *, struct sockaddr *);
453 struct	ifaddr *ifaof_ifpforaddr(struct sockaddr *, struct ifnet *);
454 
455 struct	ifmultiaddr *ifmaof_ifpforaddr(struct sockaddr *, struct ifnet *);
456 int	if_simloop(struct ifnet *ifp, struct mbuf *m, int af, int hlen);
457 
458 void	if_clone_attach(struct if_clone *);
459 void	if_clone_detach(struct if_clone *);
460 
461 int	if_clone_create(char *, int);
462 int	if_clone_destroy(const char *);
463 
464 #define IF_LLSOCKADDR(ifp)						\
465     ((struct sockaddr_dl *)(ifp)->if_lladdr->ifa_addr)
466 #define IF_LLADDR(ifp)	LLADDR(IF_LLSOCKADDR(ifp))
467 
468 #ifdef DEVICE_POLLING
469 typedef	void poll_handler_t (struct ifnet *ifp, enum poll_cmd cmd, int count);
470 int	ether_poll_register(struct ifnet *);
471 int	ether_poll_deregister(struct ifnet *);
472 void	emergency_poll_enable(const char *);
473 #endif /* DEVICE_POLLING */
474 #endif /* _KERNEL */
475 
476 #endif /* !_NET_IF_VAR_H_ */
477