xref: /dflybsd-src/sys/net/if_var.h (revision 15a56cb3807bfc9539b6ac36cb59d42bd9af9659)
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 1.32 2005/11/28 17:13:45 dillon Exp $
36  */
37 
38 #ifndef	_NET_IF_VAR_H_
39 #define	_NET_IF_VAR_H_
40 
41 #ifndef _SYS_SERIALIZE_H_
42 #include <sys/serialize.h>
43 #endif
44 
45 /*
46  * Structures defining a network interface, providing a packet
47  * transport mechanism (ala level 0 of the PUP protocols).
48  *
49  * Each interface accepts output datagrams of a specified maximum
50  * length, and provides higher level routines with input datagrams
51  * received from its medium.
52  *
53  * Output occurs when the routine if_output is called, with four parameters:
54  *	ifp->if_output(ifp, m, dst, rt)
55  * Here m is the mbuf chain to be sent and dst is the destination address.
56  * The output routine encapsulates the supplied datagram if necessary,
57  * and then transmits it on its medium.
58  *
59  * On input, each interface unwraps the data received by it, and either
60  * places it on the input queue of a internetwork datagram routine
61  * and posts the associated software interrupt, or passes the datagram to
62  * the routine if_input. It is called with the mbuf chain as parameter:
63  *	ifp->if_input(ifp, m)
64  * The input routine removes the protocol dependent header if necessary.
65  *
66  * Routines exist for locating interfaces by their addresses
67  * or for locating a interface on a certain network, as well as more general
68  * routing and gateway routines maintaining information used to locate
69  * interfaces.  These routines live in the files if.c and route.c
70  */
71 
72 /*
73  * Forward structure declarations for function prototypes [sic].
74  */
75 struct	mbuf;
76 struct	proc;
77 struct	rtentry;
78 struct	rt_addrinfo;
79 struct	socket;
80 struct	ether_header;
81 struct	ucred;
82 struct	lwkt_serialize;
83 
84 #include <sys/queue.h>		/* get TAILQ macros */
85 
86 #include <net/altq/if_altq.h>
87 
88 #ifdef _KERNEL
89 #include <sys/eventhandler.h>
90 #include <sys/mbuf.h>
91 #include <sys/systm.h>		/* XXX */
92 #include <sys/thread2.h>
93 #endif /* _KERNEL */
94 
95 #define IF_DUNIT_NONE   -1
96 
97 TAILQ_HEAD(ifnethead, ifnet);	/* we use TAILQs so that the order of */
98 TAILQ_HEAD(ifaddrhead, ifaddr);	/* instantiation is preserved in the list */
99 TAILQ_HEAD(ifprefixhead, ifprefix);
100 LIST_HEAD(ifmultihead, ifmultiaddr);
101 
102 /*
103  * Structure defining a queue for a network interface.
104  */
105 struct	ifqueue {
106 	struct	mbuf *ifq_head;
107 	struct	mbuf *ifq_tail;
108 	int	ifq_len;
109 	int	ifq_maxlen;
110 	int	ifq_drops;
111 };
112 
113 /*
114  * Note of DEVICE_POLLING
115  * 1) Any file(*.c) that depends on DEVICE_POLLING supports in this
116  *    file should include opt_polling.h at its beginning.
117  * 2) When struct changes, which are conditioned by DEVICE_POLLING,
118  *    are to be introduced, please keep the struct's size and layout
119  *    same, no matter whether DEVICE_POLLING is defined or not.
120  *    See ifnet.if_poll and ifnet.if_poll_unused for example.
121  */
122 
123 #ifdef DEVICE_POLLING
124 enum poll_cmd { POLL_ONLY, POLL_AND_CHECK_STATUS, POLL_DEREGISTER,
125 		POLL_REGISTER };
126 #endif
127 
128 /*
129  * Structure defining a network interface.
130  *
131  * (Would like to call this struct ``if'', but C isn't PL/1.)
132  */
133 
134 /*
135  * NB: For FreeBSD, it is assumed that each NIC driver's softc starts with
136  * one of these structures, typically held within an arpcom structure.
137  *
138  *	struct <foo>_softc {
139  *		struct arpcom {
140  *			struct  ifnet ac_if;
141  *			...
142  *		} <arpcom> ;
143  *		...
144  *	};
145  *
146  * The assumption is used in a number of places, including many
147  * files in sys/net, device drivers, and sys/dev/mii.c:miibus_attach().
148  *
149  * Unfortunately devices' softc are opaque, so we depend on this layout
150  * to locate the struct ifnet from the softc in the generic code.
151  *
152  * MPSAFE NOTES:
153  *
154  * ifnet and its related packet queues are protected by if_serializer.
155  * Callers of if_output, if_ioctl, if_start, if_watchdog, if_init,
156  * if_resolvemulti, and if_poll hold if_serializer.  Device drivers usually
157  * use the same serializer for their interrupt but this is not required.
158  * However, the device driver must be holding if_serializer when it
159  * calls if_input.  Note that the serializer may be temporarily released
160  * within if_input to avoid a deadlock (e.g. when fast-forwarding or
161  * bridging packets between interfaces).
162  *
163  * If a device driver installs the same serializer for its interrupt
164  * as for ifnet, then the driver only really needs to worry about further
165  * serialization in timeout based entry points.  All other entry points
166  * will already be serialized.  Older ISA drivers still using the old
167  * interrupt infrastructure will have to obtain and release the serializer
168  * in their interrupt routine themselves.
169  */
170 struct ifnet {
171 	void	*if_softc;		/* pointer to driver state */
172 	TAILQ_ENTRY(ifnet) if_link;	/* all struct ifnets are chained */
173 	char	if_xname[IFNAMSIZ];	/* external name (name + unit) */
174 	const char *if_dname;		/* driver name */
175 	int	if_dunit;		/* unit or IF_DUNIT_NONE */
176 	struct	ifaddrhead if_addrhead;	/* linked list of addresses per if */
177 	int	if_pcount;		/* number of promiscuous listeners */
178 	struct	bpf_if *if_bpf;		/* packet filter structure */
179 	u_short	if_index;		/* numeric abbreviation for this if  */
180 	short	if_timer;		/* time 'til if_watchdog called */
181 	int	if_flags;		/* up/down, broadcast, etc. */
182 	int	if_capabilities;	/* interface capabilities */
183 	int	if_capenable;		/* enabled features */
184 	void	*if_linkmib;		/* link-type-specific MIB data */
185 	size_t	if_linkmiblen;		/* length of above data */
186 	struct	if_data if_data;
187 	struct	ifmultihead if_multiaddrs; /* multicast addresses configured */
188 	int	if_amcount;		/* number of all-multicast requests */
189 /* procedure handles */
190 	int	(*if_output)		/* output routine (enqueue) */
191 		(struct ifnet *, struct mbuf *, struct sockaddr *,
192 		     struct rtentry *);
193 	void	(*if_input)		/* input routine from hardware driver */
194 		(struct ifnet *, struct mbuf *);
195 	void	(*if_start)		/* initiate output routine */
196 		(struct ifnet *);
197 	int	(*if_ioctl)		/* ioctl routine */
198 		(struct ifnet *, u_long, caddr_t, struct ucred *);
199 	void	(*if_watchdog)		/* timer routine */
200 		(struct ifnet *);
201 	void	(*if_init)		/* Init routine */
202 		(void *);
203 	int	(*if_resolvemulti)	/* validate/resolve multicast */
204 		(struct ifnet *, struct sockaddr **, struct sockaddr *);
205 #ifdef DEVICE_POLLING
206 	void	(*if_poll)		/* IFF_POLLING support */
207 		(struct ifnet *, enum poll_cmd, int);
208 #else
209 	void	(*if_poll_unused)(void); /* placeholder */
210 #endif
211 	struct	ifaltq if_snd;		/* output queue (includes altq) */
212 	struct	ifprefixhead if_prefixhead; /* list of prefixes per if */
213 	const uint8_t	*if_broadcastaddr;
214 	void	*if_afdata[AF_MAX];
215 	struct ifaddr	*if_lladdr;
216 	struct lwkt_serialize *if_serializer;	/* serializer or MP lock */
217 	struct lwkt_serialize if_default_serializer; /* if not supplied */
218 };
219 typedef void if_init_f_t (void *);
220 
221 #define	if_mtu		if_data.ifi_mtu
222 #define	if_type		if_data.ifi_type
223 #define if_physical	if_data.ifi_physical
224 #define	if_addrlen	if_data.ifi_addrlen
225 #define	if_hdrlen	if_data.ifi_hdrlen
226 #define	if_metric	if_data.ifi_metric
227 #define	if_baudrate	if_data.ifi_baudrate
228 #define	if_hwassist	if_data.ifi_hwassist
229 #define	if_ipackets	if_data.ifi_ipackets
230 #define	if_ierrors	if_data.ifi_ierrors
231 #define	if_opackets	if_data.ifi_opackets
232 #define	if_oerrors	if_data.ifi_oerrors
233 #define	if_collisions	if_data.ifi_collisions
234 #define	if_ibytes	if_data.ifi_ibytes
235 #define	if_obytes	if_data.ifi_obytes
236 #define	if_imcasts	if_data.ifi_imcasts
237 #define	if_omcasts	if_data.ifi_omcasts
238 #define	if_iqdrops	if_data.ifi_iqdrops
239 #define	if_noproto	if_data.ifi_noproto
240 #define	if_lastchange	if_data.ifi_lastchange
241 #define if_recvquota	if_data.ifi_recvquota
242 #define	if_xmitquota	if_data.ifi_xmitquota
243 #define if_rawoutput(if, m, sa) if_output(if, m, sa, (struct rtentry *)0)
244 
245 /* for compatibility with other BSDs */
246 #define	if_addrlist	if_addrhead
247 #define	if_list		if_link
248 
249 /*
250  * Output queues (ifp->if_snd) and slow device input queues (*ifp->if_slowq)
251  * are queues of messages stored on ifqueue structures
252  * (defined above).  Entries are added to and deleted from these structures
253  * by these macros, which should be called with ipl raised to splimp().
254  */
255 #define	IF_QFULL(ifq)		((ifq)->ifq_len >= (ifq)->ifq_maxlen)
256 #define	IF_DROP(ifq)		((ifq)->ifq_drops++)
257 #define	IF_QLEN(ifq)		((ifq)->ifq_len)
258 #define	IF_QEMPTY(ifq)		(IF_QLEN(ifq) == 0)
259 #define	IF_ENQUEUE(ifq, m) { \
260 	(m)->m_nextpkt = 0; \
261 	if ((ifq)->ifq_tail == 0) \
262 		(ifq)->ifq_head = m; \
263 	else \
264 		(ifq)->ifq_tail->m_nextpkt = m; \
265 	(ifq)->ifq_tail = m; \
266 	(ifq)->ifq_len++; \
267 }
268 #define	IF_PREPEND(ifq, m) { \
269 	(m)->m_nextpkt = (ifq)->ifq_head; \
270 	if ((ifq)->ifq_tail == 0) \
271 		(ifq)->ifq_tail = (m); \
272 	(ifq)->ifq_head = (m); \
273 	(ifq)->ifq_len++; \
274 }
275 #define	IF_DEQUEUE(ifq, m) { \
276 	(m) = (ifq)->ifq_head; \
277 	if (m) { \
278 		if (((ifq)->ifq_head = (m)->m_nextpkt) == 0) \
279 			(ifq)->ifq_tail = 0; \
280 		(m)->m_nextpkt = 0; \
281 		(ifq)->ifq_len--; \
282 	} \
283 }
284 
285 #define	IF_POLL(ifq, m)		((m) = (ifq)->ifq_head)
286 
287 #define IF_DRAIN(ifq) do {						\
288 	struct mbuf *m;							\
289 	while (1) {							\
290 		IF_DEQUEUE(ifq, m);					\
291 		if (m == NULL)						\
292 			break;						\
293 		m_freem(m);						\
294 	}								\
295 } while (0)
296 
297 #ifdef _KERNEL
298 
299 /*
300  * DEPRECATED - should not be used by any new driver.  This code uses the
301  * old queueing interface and if_start ABI and does not use the ifp's
302  * serializer.
303  */
304 #define IF_HANDOFF(ifq, m, ifp)			if_handoff(ifq, m, ifp, 0)
305 #define IF_HANDOFF_ADJ(ifq, m, ifp, adj)	if_handoff(ifq, m, ifp, adj)
306 
307 static __inline int
308 if_handoff(struct ifqueue *_ifq, struct mbuf *_m, struct ifnet *_ifp,
309 	   int _adjust)
310 {
311 	int _need_if_start = 0;
312 
313 	crit_enter();
314 
315 	if (IF_QFULL(_ifq)) {
316 		IF_DROP(_ifq);
317 		crit_exit();
318 		m_freem(_m);
319 		return (0);
320 	}
321 	if (_ifp != NULL) {
322 		_ifp->if_obytes += _m->m_pkthdr.len + _adjust;
323 		if (_m->m_flags & M_MCAST)
324 			_ifp->if_omcasts++;
325 		_need_if_start = !(_ifp->if_flags & IFF_OACTIVE);
326 	}
327 	IF_ENQUEUE(_ifq, _m);
328 	if (_need_if_start) {
329 		(*_ifp->if_start)(_ifp);
330 	}
331 	crit_exit();
332 	return (1);
333 }
334 
335 /*
336  * 72 was chosen below because it is the size of a TCP/IP
337  * header (40) + the minimum mss (32).
338  */
339 #define	IF_MINMTU	72
340 #define	IF_MAXMTU	65535
341 
342 #endif /* _KERNEL */
343 
344 /*
345  * The ifaddr structure contains information about one address
346  * of an interface.  They are maintained by the different address families,
347  * are allocated and attached when an address is set, and are linked
348  * together so all addresses for an interface can be located.
349  */
350 struct ifaddr {
351 	struct	sockaddr *ifa_addr;	/* address of interface */
352 	struct	sockaddr *ifa_dstaddr;	/* other end of p-to-p link */
353 #define	ifa_broadaddr	ifa_dstaddr	/* broadcast address interface */
354 	struct	sockaddr *ifa_netmask;	/* used to determine subnet */
355 	struct	if_data if_data;	/* not all members are meaningful */
356 	struct	ifnet *ifa_ifp;		/* back-pointer to interface */
357 	TAILQ_ENTRY(ifaddr) ifa_link;	/* queue macro glue */
358 	void	(*ifa_rtrequest)	/* check or clean routes (+ or -)'d */
359 		(int, struct rtentry *, struct rt_addrinfo *);
360 	u_short	ifa_flags;		/* mostly rt_flags for cloning */
361 	u_int	ifa_refcnt;		/* references to this structure */
362 	int	ifa_metric;		/* cost of going out this interface */
363 #ifdef notdef
364 	struct	rtentry *ifa_rt;	/* XXXX for ROUTETOIF ????? */
365 #endif
366 	int (*ifa_claim_addr)		/* check if an addr goes to this if */
367 		(struct ifaddr *, struct sockaddr *);
368 
369 };
370 #define	IFA_ROUTE	RTF_UP		/* route installed */
371 
372 /* for compatibility with other BSDs */
373 #define	ifa_list	ifa_link
374 
375 /*
376  * The prefix structure contains information about one prefix
377  * of an interface.  They are maintained by the different address families,
378  * are allocated and attached when an prefix or an address is set,
379  * and are linked together so all prefixes for an interface can be located.
380  */
381 struct ifprefix {
382 	struct	sockaddr *ifpr_prefix;	/* prefix of interface */
383 	struct	ifnet *ifpr_ifp;	/* back-pointer to interface */
384 	TAILQ_ENTRY(ifprefix) ifpr_list; /* queue macro glue */
385 	u_char	ifpr_plen;		/* prefix length in bits */
386 	u_char	ifpr_type;		/* protocol dependent prefix type */
387 };
388 
389 /*
390  * Multicast address structure.  This is analogous to the ifaddr
391  * structure except that it keeps track of multicast addresses.
392  * Also, the reference count here is a count of requests for this
393  * address, not a count of pointers to this structure.
394  */
395 struct ifmultiaddr {
396 	LIST_ENTRY(ifmultiaddr) ifma_link; /* queue macro glue */
397 	struct	sockaddr *ifma_addr;	/* address this membership is for */
398 	struct	sockaddr *ifma_lladdr;	/* link-layer translation, if any */
399 	struct	ifnet *ifma_ifp;	/* back-pointer to interface */
400 	u_int	ifma_refcount;		/* reference count */
401 	void	*ifma_protospec;	/* protocol-specific state, if any */
402 };
403 
404 #ifdef _KERNEL
405 /* interface address change event */
406 typedef void (*ifaddr_event_handler_t)(void *, struct ifnet *);
407 EVENTHANDLER_DECLARE(ifaddr_event, ifaddr_event_handler_t);
408 /* new interface attach event */
409 typedef void (*ifnet_attach_event_handler_t)(void *, struct ifnet *);
410 EVENTHANDLER_DECLARE(ifnet_attach_event, ifnet_attach_event_handler_t);
411 /* interface detach event */
412 typedef void (*ifnet_detach_event_handler_t)(void *, struct ifnet *);
413 EVENTHANDLER_DECLARE(ifnet_detach_event, ifnet_detach_event_handler_t);
414 /* interface clone event */
415 typedef void (*if_clone_event_handler_t)(void *, struct if_clone *);
416 EVENTHANDLER_DECLARE(if_clone_event, if_clone_event_handler_t);
417 
418 static __inline void
419 IFAREF(struct ifaddr *_ifa)
420 {
421 	++_ifa->ifa_refcnt;
422 }
423 
424 #include <sys/malloc.h>
425 
426 MALLOC_DECLARE(M_IFADDR);
427 MALLOC_DECLARE(M_IFMADDR);
428 
429 static __inline void
430 IFAFREE(struct ifaddr *_ifa)
431 {
432 	if (_ifa->ifa_refcnt <= 0)
433 		free(_ifa, M_IFADDR);
434 	else
435 		_ifa->ifa_refcnt--;
436 }
437 
438 extern	struct ifnethead ifnet;
439 extern struct	ifnet	**ifindex2ifnet;
440 extern	int ifqmaxlen;
441 extern	struct ifnet loif[];
442 extern	int if_index;
443 
444 void	ether_ifattach(struct ifnet *, uint8_t *, struct lwkt_serialize *);
445 void	ether_ifattach_bpf(struct ifnet *, uint8_t *, u_int, u_int,
446 			struct lwkt_serialize *);
447 void	ether_ifdetach(struct ifnet *);
448 void	ether_input(struct ifnet *, struct ether_header *, struct mbuf *);
449 void	ether_demux(struct ifnet *, struct ether_header *, struct mbuf *);
450 int	ether_output_frame(struct ifnet *, struct mbuf *);
451 int	ether_ioctl(struct ifnet *, int, caddr_t);
452 uint32_t	ether_crc32_le(const uint8_t *, size_t);
453 uint32_t	ether_crc32_be(const uint8_t *, size_t);
454 
455 int	if_addmulti(struct ifnet *, struct sockaddr *, struct ifmultiaddr **);
456 int	if_allmulti(struct ifnet *, int);
457 void	if_attach(struct ifnet *, struct lwkt_serialize *);
458 int	if_delmulti(struct ifnet *, struct sockaddr *);
459 void	if_detach(struct ifnet *);
460 void	if_down(struct ifnet *);
461 void	if_initname(struct ifnet *, const char *, int);
462 int	if_printf(struct ifnet *, const char *, ...) __printflike(2, 3);
463 void	if_route(struct ifnet *, int flag, int fam);
464 int	if_setlladdr(struct ifnet *, const u_char *, int);
465 void	if_unroute(struct ifnet *, int flag, int fam);
466 void	if_up(struct ifnet *);
467 /*void	ifinit(void);*/ /* declared in systm.h for main() */
468 int	ifioctl(struct socket *, u_long, caddr_t, struct thread *);
469 int	ifpromisc(struct ifnet *, int);
470 struct	ifnet *ifunit(const char *);
471 struct	ifnet *if_withname(struct sockaddr *);
472 
473 struct	ifaddr *ifa_ifwithaddr(struct sockaddr *);
474 struct	ifaddr *ifa_ifwithdstaddr(struct sockaddr *);
475 struct	ifaddr *ifa_ifwithnet(struct sockaddr *);
476 struct	ifaddr *ifa_ifwithroute(int, struct sockaddr *, struct sockaddr *);
477 struct	ifaddr *ifaof_ifpforaddr(struct sockaddr *, struct ifnet *);
478 
479 struct	ifmultiaddr *ifmaof_ifpforaddr(struct sockaddr *, struct ifnet *);
480 int	if_simloop(struct ifnet *ifp, struct mbuf *m, int af, int hlen);
481 
482 void	if_clone_attach(struct if_clone *);
483 void	if_clone_detach(struct if_clone *);
484 
485 int	if_clone_create(char *, int);
486 int	if_clone_destroy(const char *);
487 
488 #define IF_LLSOCKADDR(ifp)						\
489     ((struct sockaddr_dl *)(ifp)->if_lladdr->ifa_addr)
490 #define IF_LLADDR(ifp)	LLADDR(IF_LLSOCKADDR(ifp))
491 
492 #ifdef DEVICE_POLLING
493 typedef	void poll_handler_t (struct ifnet *ifp, enum poll_cmd cmd, int count);
494 int	ether_poll_register(struct ifnet *);
495 int	ether_poll_deregister(struct ifnet *);
496 void	emergency_poll_enable(const char *);
497 #endif /* DEVICE_POLLING */
498 #endif /* _KERNEL */
499 
500 #endif /* !_NET_IF_VAR_H_ */
501