xref: /dflybsd-src/sys/net/if_var.h (revision b5b0912b1891e95ccc48cad83f09239ccb7ffc16)
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 1.29 2005/06/05 12:35:24 joerg 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 #endif /* _KERNEL */
88 
89 #define IF_DUNIT_NONE   -1
90 
91 TAILQ_HEAD(ifnethead, ifnet);	/* we use TAILQs so that the order of */
92 TAILQ_HEAD(ifaddrhead, ifaddr);	/* instantiation is preserved in the list */
93 TAILQ_HEAD(ifprefixhead, ifprefix);
94 LIST_HEAD(ifmultihead, ifmultiaddr);
95 
96 /*
97  * Structure defining a queue for a network interface.
98  */
99 struct	ifqueue {
100 	struct	mbuf *ifq_head;
101 	struct	mbuf *ifq_tail;
102 	int	ifq_len;
103 	int	ifq_maxlen;
104 	int	ifq_drops;
105 };
106 
107 #ifdef DEVICE_POLLING
108 enum poll_cmd { POLL_ONLY, POLL_AND_CHECK_STATUS, POLL_DEREGISTER,
109 		POLL_REGISTER };
110 #endif
111 
112 /*
113  * Structure defining a network interface.
114  *
115  * (Would like to call this struct ``if'', but C isn't PL/1.)
116  */
117 
118 /*
119  * NB: For FreeBSD, it is assumed that each NIC driver's softc starts with
120  * one of these structures, typically held within an arpcom structure.
121  *
122  *	struct <foo>_softc {
123  *		struct arpcom {
124  *			struct  ifnet ac_if;
125  *			...
126  *		} <arpcom> ;
127  *		...
128  *	};
129  *
130  * The assumption is used in a number of places, including many
131  * files in sys/net, device drivers, and sys/dev/mii.c:miibus_attach().
132  *
133  * Unfortunately devices' softc are opaque, so we depend on this layout
134  * to locate the struct ifnet from the softc in the generic code.
135  *
136  * Note that not all fields are used by drivers in the FreeBSD source
137  * tree. However, who knows what third party software does with fields
138  * marked as "unused", such as if_ipending, if_done, and if_poll*,
139  * so any attemt to redefine their meaning might end up in binary
140  * compatibility problems, even if the size of struct ifnet, and
141  * the size and position of its fields do not change.
142  * We just have to live with that.
143  */
144 struct ifnet {
145 	void	*if_softc;		/* pointer to driver state */
146 	TAILQ_ENTRY(ifnet) if_link;	/* all struct ifnets are chained */
147 	char	if_xname[IFNAMSIZ];	/* external name (name + unit) */
148 	const char *if_dname;		/* driver name */
149 	int	if_dunit;		/* unit or IF_DUNIT_NONE */
150 	struct	ifaddrhead if_addrhead;	/* linked list of addresses per if */
151 	int	if_pcount;		/* number of promiscuous listeners */
152 	struct	bpf_if *if_bpf;		/* packet filter structure */
153 	u_short	if_index;		/* numeric abbreviation for this if  */
154 	short	if_timer;		/* time 'til if_watchdog called */
155 	int	if_flags;		/* up/down, broadcast, etc. */
156 	int	if_capabilities;	/* interface capabilities */
157 	int	if_capenable;		/* enabled features */
158 	void	*if_linkmib;		/* link-type-specific MIB data */
159 	size_t	if_linkmiblen;		/* length of above data */
160 	struct	if_data if_data;
161 	struct	ifmultihead if_multiaddrs; /* multicast addresses configured */
162 	int	if_amcount;		/* number of all-multicast requests */
163 /* procedure handles */
164 	int	(*if_output)		/* output routine (enqueue) */
165 		(struct ifnet *, struct mbuf *, struct sockaddr *,
166 		     struct rtentry *);
167 	void	(*if_input)		/* input routine from hardware driver */
168 		(struct ifnet *, struct mbuf *);
169 	void	(*if_start)		/* initiate output routine */
170 		(struct ifnet *);
171 	int	(*if_ioctl)		/* ioctl routine */
172 		(struct ifnet *, u_long, caddr_t, struct ucred *);
173 	void	(*if_watchdog)		/* timer routine */
174 		(struct ifnet *);
175 	void	(*if_init)		/* Init routine */
176 		(void *);
177 	int	(*if_resolvemulti)	/* validate/resolve multicast */
178 		(struct ifnet *, struct sockaddr **, struct sockaddr *);
179 #ifdef DEVICE_POLLING
180 	void	(*if_poll)		/* IFF_POLLING support */
181 		(struct ifnet *, enum poll_cmd, int);
182 #else
183 	void	(*if_poll_unused)(void); /* placeholder */
184 #endif
185 	struct	ifaltq if_snd;		/* output queue (includes altq) */
186 	struct	ifprefixhead if_prefixhead; /* list of prefixes per if */
187 	const uint8_t	*if_broadcastaddr;
188 	void	*if_afdata[AF_MAX];
189 	struct ifaddr	*if_lladdr;
190 };
191 typedef void if_init_f_t (void *);
192 
193 #define	if_mtu		if_data.ifi_mtu
194 #define	if_type		if_data.ifi_type
195 #define if_physical	if_data.ifi_physical
196 #define	if_addrlen	if_data.ifi_addrlen
197 #define	if_hdrlen	if_data.ifi_hdrlen
198 #define	if_metric	if_data.ifi_metric
199 #define	if_baudrate	if_data.ifi_baudrate
200 #define	if_hwassist	if_data.ifi_hwassist
201 #define	if_ipackets	if_data.ifi_ipackets
202 #define	if_ierrors	if_data.ifi_ierrors
203 #define	if_opackets	if_data.ifi_opackets
204 #define	if_oerrors	if_data.ifi_oerrors
205 #define	if_collisions	if_data.ifi_collisions
206 #define	if_ibytes	if_data.ifi_ibytes
207 #define	if_obytes	if_data.ifi_obytes
208 #define	if_imcasts	if_data.ifi_imcasts
209 #define	if_omcasts	if_data.ifi_omcasts
210 #define	if_iqdrops	if_data.ifi_iqdrops
211 #define	if_noproto	if_data.ifi_noproto
212 #define	if_lastchange	if_data.ifi_lastchange
213 #define if_recvquota	if_data.ifi_recvquota
214 #define	if_xmitquota	if_data.ifi_xmitquota
215 #define if_rawoutput(if, m, sa) if_output(if, m, sa, (struct rtentry *)0)
216 
217 /* for compatibility with other BSDs */
218 #define	if_addrlist	if_addrhead
219 #define	if_list		if_link
220 
221 /*
222  * Output queues (ifp->if_snd) and slow device input queues (*ifp->if_slowq)
223  * are queues of messages stored on ifqueue structures
224  * (defined above).  Entries are added to and deleted from these structures
225  * by these macros, which should be called with ipl raised to splimp().
226  */
227 #define	IF_QFULL(ifq)		((ifq)->ifq_len >= (ifq)->ifq_maxlen)
228 #define	IF_DROP(ifq)		((ifq)->ifq_drops++)
229 #define	IF_QLEN(ifq)		((ifq)->ifq_len)
230 #define	IF_QEMPTY(ifq)		(IF_QLEN(ifq) == 0)
231 #define	IF_ENQUEUE(ifq, m) { \
232 	(m)->m_nextpkt = 0; \
233 	if ((ifq)->ifq_tail == 0) \
234 		(ifq)->ifq_head = m; \
235 	else \
236 		(ifq)->ifq_tail->m_nextpkt = m; \
237 	(ifq)->ifq_tail = m; \
238 	(ifq)->ifq_len++; \
239 }
240 #define	IF_PREPEND(ifq, m) { \
241 	(m)->m_nextpkt = (ifq)->ifq_head; \
242 	if ((ifq)->ifq_tail == 0) \
243 		(ifq)->ifq_tail = (m); \
244 	(ifq)->ifq_head = (m); \
245 	(ifq)->ifq_len++; \
246 }
247 #define	IF_DEQUEUE(ifq, m) { \
248 	(m) = (ifq)->ifq_head; \
249 	if (m) { \
250 		if (((ifq)->ifq_head = (m)->m_nextpkt) == 0) \
251 			(ifq)->ifq_tail = 0; \
252 		(m)->m_nextpkt = 0; \
253 		(ifq)->ifq_len--; \
254 	} \
255 }
256 
257 #define	IF_POLL(ifq, m)		((m) = (ifq)->ifq_head)
258 
259 #define IF_DRAIN(ifq) do {						\
260 	struct mbuf *m;							\
261 	while (1) {							\
262 		IF_DEQUEUE(ifq, m);					\
263 		if (m == NULL)						\
264 			break;						\
265 		m_freem(m);						\
266 	}								\
267 } while (0)
268 
269 #ifdef _KERNEL
270 
271 #define IF_HANDOFF(ifq, m, ifp)			if_handoff(ifq, m, ifp, 0)
272 #define IF_HANDOFF_ADJ(ifq, m, ifp, adj)	if_handoff(ifq, m, ifp, adj)
273 
274 static __inline int
275 if_handoff(struct ifqueue *_ifq, struct mbuf *_m, struct ifnet *_ifp,
276 	   int _adjust)
277 {
278 	int _need_if_start = 0;
279 	int _s = splimp();
280 
281 	if (IF_QFULL(_ifq)) {
282 		IF_DROP(_ifq);
283 		splx(_s);
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 		_need_if_start = !(_ifp->if_flags & IFF_OACTIVE);
292 	}
293 	IF_ENQUEUE(_ifq, _m);
294 	if (_need_if_start)
295 		(*_ifp->if_start)(_ifp);
296 	splx(_s);
297 	return (1);
298 }
299 
300 /*
301  * 72 was chosen below because it is the size of a TCP/IP
302  * header (40) + the minimum mss (32).
303  */
304 #define	IF_MINMTU	72
305 #define	IF_MAXMTU	65535
306 
307 #endif /* _KERNEL */
308 
309 /*
310  * The ifaddr structure contains information about one address
311  * of an interface.  They are maintained by the different address families,
312  * are allocated and attached when an address is set, and are linked
313  * together so all addresses for an interface can be located.
314  */
315 struct ifaddr {
316 	struct	sockaddr *ifa_addr;	/* address of interface */
317 	struct	sockaddr *ifa_dstaddr;	/* other end of p-to-p link */
318 #define	ifa_broadaddr	ifa_dstaddr	/* broadcast address interface */
319 	struct	sockaddr *ifa_netmask;	/* used to determine subnet */
320 	struct	if_data if_data;	/* not all members are meaningful */
321 	struct	ifnet *ifa_ifp;		/* back-pointer to interface */
322 	TAILQ_ENTRY(ifaddr) ifa_link;	/* queue macro glue */
323 	void	(*ifa_rtrequest)	/* check or clean routes (+ or -)'d */
324 		(int, struct rtentry *, struct rt_addrinfo *);
325 	u_short	ifa_flags;		/* mostly rt_flags for cloning */
326 	u_int	ifa_refcnt;		/* references to this structure */
327 	int	ifa_metric;		/* cost of going out this interface */
328 #ifdef notdef
329 	struct	rtentry *ifa_rt;	/* XXXX for ROUTETOIF ????? */
330 #endif
331 	int (*ifa_claim_addr)		/* check if an addr goes to this if */
332 		(struct ifaddr *, struct sockaddr *);
333 
334 };
335 #define	IFA_ROUTE	RTF_UP		/* route installed */
336 
337 /* for compatibility with other BSDs */
338 #define	ifa_list	ifa_link
339 
340 /*
341  * The prefix structure contains information about one prefix
342  * of an interface.  They are maintained by the different address families,
343  * are allocated and attached when an prefix or an address is set,
344  * and are linked together so all prefixes for an interface can be located.
345  */
346 struct ifprefix {
347 	struct	sockaddr *ifpr_prefix;	/* prefix of interface */
348 	struct	ifnet *ifpr_ifp;	/* back-pointer to interface */
349 	TAILQ_ENTRY(ifprefix) ifpr_list; /* queue macro glue */
350 	u_char	ifpr_plen;		/* prefix length in bits */
351 	u_char	ifpr_type;		/* protocol dependent prefix type */
352 };
353 
354 /*
355  * Multicast address structure.  This is analogous to the ifaddr
356  * structure except that it keeps track of multicast addresses.
357  * Also, the reference count here is a count of requests for this
358  * address, not a count of pointers to this structure.
359  */
360 struct ifmultiaddr {
361 	LIST_ENTRY(ifmultiaddr) ifma_link; /* queue macro glue */
362 	struct	sockaddr *ifma_addr;	/* address this membership is for */
363 	struct	sockaddr *ifma_lladdr;	/* link-layer translation, if any */
364 	struct	ifnet *ifma_ifp;	/* back-pointer to interface */
365 	u_int	ifma_refcount;		/* reference count */
366 	void	*ifma_protospec;	/* protocol-specific state, if any */
367 };
368 
369 #ifdef _KERNEL
370 /* interface address change event */
371 typedef void (*ifaddr_event_handler_t)(void *, struct ifnet *);
372 EVENTHANDLER_DECLARE(ifaddr_event, ifaddr_event_handler_t);
373 /* new interface attach event */
374 typedef void (*ifnet_attach_event_handler_t)(void *, struct ifnet *);
375 EVENTHANDLER_DECLARE(ifnet_attach_event, ifnet_attach_event_handler_t);
376 /* interface detach event */
377 typedef void (*ifnet_detach_event_handler_t)(void *, struct ifnet *);
378 EVENTHANDLER_DECLARE(ifnet_detach_event, ifnet_detach_event_handler_t);
379 /* interface clone event */
380 typedef void (*if_clone_event_handler_t)(void *, struct if_clone *);
381 EVENTHANDLER_DECLARE(if_clone_event, if_clone_event_handler_t);
382 
383 static __inline void
384 IFAREF(struct ifaddr *_ifa)
385 {
386 	++_ifa->ifa_refcnt;
387 }
388 
389 #include <sys/malloc.h>
390 
391 MALLOC_DECLARE(M_IFADDR);
392 MALLOC_DECLARE(M_IFMADDR);
393 
394 static __inline void
395 IFAFREE(struct ifaddr *_ifa)
396 {
397 	if (_ifa->ifa_refcnt <= 0)
398 		free(_ifa, M_IFADDR);
399 	else
400 		_ifa->ifa_refcnt--;
401 }
402 
403 extern	struct ifnethead ifnet;
404 extern struct	ifnet	**ifindex2ifnet;
405 extern	int ifqmaxlen;
406 extern	struct ifnet loif[];
407 extern	int if_index;
408 
409 void	ether_ifattach(struct ifnet *, uint8_t *);
410 void	ether_ifattach_bpf(struct ifnet *, uint8_t *, u_int, u_int);
411 void	ether_ifdetach(struct ifnet *);
412 void	ether_input(struct ifnet *, struct ether_header *, struct mbuf *);
413 void	ether_demux(struct ifnet *, struct ether_header *, struct mbuf *);
414 int	ether_output_frame(struct ifnet *, struct mbuf *);
415 int	ether_ioctl(struct ifnet *, int, caddr_t);
416 uint32_t	ether_crc32_le(const uint8_t *, size_t);
417 uint32_t	ether_crc32_be(const uint8_t *, size_t);
418 
419 int	if_addmulti(struct ifnet *, struct sockaddr *, struct ifmultiaddr **);
420 int	if_allmulti(struct ifnet *, int);
421 void	if_attach(struct ifnet *);
422 int	if_delmulti(struct ifnet *, struct sockaddr *);
423 void	if_detach(struct ifnet *);
424 void	if_down(struct ifnet *);
425 void	if_initname(struct ifnet *, const char *, int);
426 int	if_printf(struct ifnet *, const char *, ...) __printflike(2, 3);
427 void	if_route(struct ifnet *, int flag, int fam);
428 int	if_setlladdr(struct ifnet *, const u_char *, int);
429 void	if_unroute(struct ifnet *, int flag, int fam);
430 void	if_up(struct ifnet *);
431 /*void	ifinit(void);*/ /* declared in systm.h for main() */
432 int	ifioctl(struct socket *, u_long, caddr_t, struct thread *);
433 int	ifpromisc(struct ifnet *, int);
434 struct	ifnet *ifunit(const char *);
435 struct	ifnet *if_withname(struct sockaddr *);
436 
437 struct	ifaddr *ifa_ifwithaddr(struct sockaddr *);
438 struct	ifaddr *ifa_ifwithdstaddr(struct sockaddr *);
439 struct	ifaddr *ifa_ifwithnet(struct sockaddr *);
440 struct	ifaddr *ifa_ifwithroute(int, struct sockaddr *, struct sockaddr *);
441 struct	ifaddr *ifaof_ifpforaddr(struct sockaddr *, struct ifnet *);
442 
443 struct	ifmultiaddr *ifmaof_ifpforaddr(struct sockaddr *, struct ifnet *);
444 int	if_simloop(struct ifnet *ifp, struct mbuf *m, int af, int hlen);
445 
446 void	if_clone_attach(struct if_clone *);
447 void	if_clone_detach(struct if_clone *);
448 
449 int	if_clone_create(char *, int);
450 int	if_clone_destroy(const char *);
451 
452 #define IF_LLSOCKADDR(ifp)						\
453     ((struct sockaddr_dl *)(ifp)->if_lladdr->ifa_addr)
454 #define IF_LLADDR(ifp)	LLADDR(IF_LLSOCKADDR(ifp))
455 
456 #ifdef DEVICE_POLLING
457 typedef	void poll_handler_t (struct ifnet *ifp, enum poll_cmd cmd, int count);
458 int	ether_poll_register(struct ifnet *);
459 int	ether_poll_deregister(struct ifnet *);
460 void	emergency_poll_enable(const char *);
461 #endif /* DEVICE_POLLING */
462 #endif /* _KERNEL */
463 
464 #endif /* !_NET_IF_VAR_H_ */
465