if_llatbl.h revision 286624 
1/*
2 * Copyright (c) 2004 Luigi Rizzo, Alessandro Cerri. All rights reserved.
3 * Copyright (c) 2004-2008 Qing Li. All rights reserved.
4 * Copyright (c) 2008 Kip Macy. All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 */
27#include <sys/cdefs.h>
28__FBSDID("$FreeBSD: head/sys/net/if_llatbl.h 286624 2015-08-11 09:26:11Z melifaro $");
29
30#ifndef	_NET_IF_LLATBL_H_
31#define	_NET_IF_LLATBL_H_
32
33#include <sys/_rwlock.h>
34#include <netinet/in.h>
35
36struct ifnet;
37struct sysctl_req;
38struct rt_msghdr;
39struct rt_addrinfo;
40
41struct llentry;
42LIST_HEAD(llentries, llentry);
43
44extern struct rwlock lltable_rwlock;
45#define	LLTABLE_RLOCK()		rw_rlock(&lltable_rwlock)
46#define	LLTABLE_RUNLOCK()	rw_runlock(&lltable_rwlock)
47#define	LLTABLE_WLOCK()		rw_wlock(&lltable_rwlock)
48#define	LLTABLE_WUNLOCK()	rw_wunlock(&lltable_rwlock)
49#define	LLTABLE_LOCK_ASSERT()	rw_assert(&lltable_rwlock, RA_LOCKED)
50
51/*
52 * Code referencing llentry must at least hold
53 * a shared lock
54 */
55struct llentry {
56	LIST_ENTRY(llentry)	 lle_next;
57	union {
58		struct in_addr	addr4;
59		struct in6_addr	addr6;
60	} r_l3addr;
61	union {
62		uint64_t	mac_aligned;
63		uint16_t	mac16[3];
64		uint8_t		mac8[20];	/* IB needs 20 bytes. */
65	} ll_addr;
66	uint32_t		spare0;
67	uint64_t		spare1;
68
69	struct lltable		 *lle_tbl;
70	struct llentries	 *lle_head;
71	void			(*lle_free)(struct llentry *);
72	struct mbuf		 *la_hold;
73	int			 la_numheld;  /* # of packets currently held */
74	time_t			 la_expire;
75	uint16_t		 la_flags;
76	uint16_t		 la_asked;
77	uint16_t		 la_preempt;
78	uint16_t		 ln_byhint;
79	int16_t			 ln_state;	/* IPv6 has ND6_LLINFO_NOSTATE == -2 */
80	uint16_t		 ln_router;
81	time_t			 ln_ntick;
82	int			 lle_refcnt;
83
84	LIST_ENTRY(llentry)	lle_chain;	/* chain of deleted items */
85	/* XXX af-private? */
86	union {
87		struct callout	ln_timer_ch;
88		struct callout  la_timer;
89	} lle_timer;
90	struct rwlock		 lle_lock;
91};
92
93#define	LLE_WLOCK(lle)		rw_wlock(&(lle)->lle_lock)
94#define	LLE_RLOCK(lle)		rw_rlock(&(lle)->lle_lock)
95#define	LLE_WUNLOCK(lle)	rw_wunlock(&(lle)->lle_lock)
96#define	LLE_RUNLOCK(lle)	rw_runlock(&(lle)->lle_lock)
97#define	LLE_DOWNGRADE(lle)	rw_downgrade(&(lle)->lle_lock)
98#define	LLE_TRY_UPGRADE(lle)	rw_try_upgrade(&(lle)->lle_lock)
99#define	LLE_LOCK_INIT(lle)	rw_init_flags(&(lle)->lle_lock, "lle", RW_DUPOK)
100#define	LLE_LOCK_DESTROY(lle)	rw_destroy(&(lle)->lle_lock)
101#define	LLE_WLOCK_ASSERT(lle)	rw_assert(&(lle)->lle_lock, RA_WLOCKED)
102
103#define LLE_IS_VALID(lle)	(((lle) != NULL) && ((lle) != (void *)-1))
104
105#define	LLE_ADDREF(lle) do {					\
106	LLE_WLOCK_ASSERT(lle);					\
107	KASSERT((lle)->lle_refcnt >= 0,				\
108	    ("negative refcnt %d on lle %p",			\
109	    (lle)->lle_refcnt, (lle)));				\
110	(lle)->lle_refcnt++;					\
111} while (0)
112
113#define	LLE_REMREF(lle)	do {					\
114	LLE_WLOCK_ASSERT(lle);					\
115	KASSERT((lle)->lle_refcnt > 0,				\
116	    ("bogus refcnt %d on lle %p",			\
117	    (lle)->lle_refcnt, (lle)));				\
118	(lle)->lle_refcnt--;					\
119} while (0)
120
121#define	LLE_FREE_LOCKED(lle) do {				\
122	if ((lle)->lle_refcnt == 1)				\
123		(lle)->lle_free(lle);				\
124	else {							\
125		LLE_REMREF(lle);				\
126		LLE_WUNLOCK(lle);				\
127	}							\
128	/* guard against invalid refs */			\
129	(lle) = NULL;						\
130} while (0)
131
132#define	LLE_FREE(lle) do {					\
133	LLE_WLOCK(lle);						\
134	LLE_FREE_LOCKED(lle);					\
135} while (0)
136
137
138#define	ln_timer_ch	lle_timer.ln_timer_ch
139#define	la_timer	lle_timer.la_timer
140
141typedef	struct llentry *(llt_lookup_t)(struct lltable *, u_int flags,
142    const struct sockaddr *l3addr);
143typedef	struct llentry *(llt_create_t)(struct lltable *, u_int flags,
144    const struct sockaddr *l3addr);
145typedef	int (llt_delete_t)(struct lltable *, u_int flags,
146    const struct sockaddr *l3addr);
147typedef void (llt_prefix_free_t)(struct lltable *,
148    const struct sockaddr *prefix, const struct sockaddr *mask, u_int flags);
149typedef int (llt_dump_entry_t)(struct lltable *, struct llentry *,
150    struct sysctl_req *);
151typedef uint32_t (llt_hash_t)(const struct llentry *, uint32_t);
152typedef int (llt_match_prefix_t)(const struct sockaddr *,
153    const struct sockaddr *, u_int, struct llentry *);
154typedef void (llt_free_entry_t)(struct lltable *, struct llentry *);
155typedef void (llt_fill_sa_entry_t)(const struct llentry *, struct sockaddr *);
156typedef void (llt_free_tbl_t)(struct lltable *);
157typedef void (llt_link_entry_t)(struct lltable *, struct llentry *);
158typedef void (llt_unlink_entry_t)(struct llentry *);
159
160typedef int (llt_foreach_cb_t)(struct lltable *, struct llentry *, void *);
161typedef int (llt_foreach_entry_t)(struct lltable *, llt_foreach_cb_t *, void *);
162
163struct lltable {
164	SLIST_ENTRY(lltable)	llt_link;
165	int			llt_af;
166	int			llt_hsize;
167	struct llentries	*lle_head;
168	struct ifnet		*llt_ifp;
169
170	llt_lookup_t		*llt_lookup;
171	llt_create_t		*llt_create;
172	llt_delete_t		*llt_delete;
173	llt_prefix_free_t	*llt_prefix_free;
174	llt_dump_entry_t	*llt_dump_entry;
175	llt_hash_t		*llt_hash;
176	llt_match_prefix_t	*llt_match_prefix;
177	llt_free_entry_t	*llt_free_entry;
178	llt_foreach_entry_t	*llt_foreach_entry;
179	llt_link_entry_t	*llt_link_entry;
180	llt_unlink_entry_t	*llt_unlink_entry;
181	llt_fill_sa_entry_t	*llt_fill_sa_entry;
182	llt_free_tbl_t		*llt_free_tbl;
183};
184
185MALLOC_DECLARE(M_LLTABLE);
186
187/*
188 * LLentry flags
189 */
190#define	LLE_DELETED	0x0001	/* entry must be deleted */
191#define	LLE_STATIC	0x0002	/* entry is static */
192#define	LLE_IFADDR	0x0004	/* entry is interface addr */
193#define	LLE_VALID	0x0008	/* ll_addr is valid */
194#define	LLE_PUB		0x0020	/* publish entry ??? */
195#define	LLE_LINKED	0x0040	/* linked to lookup structure */
196/* LLE request flags */
197#define	LLE_EXCLUSIVE	0x2000	/* return lle xlocked  */
198
199#define LLATBL_HASH(key, mask) \
200	(((((((key >> 8) ^ key) >> 8) ^ key) >> 8) ^ key) & mask)
201
202struct lltable *lltable_allocate_htbl(uint32_t hsize);
203void		lltable_free(struct lltable *);
204void		lltable_link(struct lltable *llt);
205void		lltable_prefix_free(int, struct sockaddr *,
206		    struct sockaddr *, u_int);
207#if 0
208void		lltable_drain(int);
209#endif
210int		lltable_sysctl_dumparp(int, struct sysctl_req *);
211
212size_t		llentry_free(struct llentry *);
213struct llentry  *llentry_alloc(struct ifnet *, struct lltable *,
214		    struct sockaddr_storage *);
215
216/* helper functions */
217size_t lltable_drop_entry_queue(struct llentry *);
218
219struct llentry *lltable_create_lle(struct lltable *llt, u_int flags,
220    const void *paddr);
221void lltable_link_entry(struct lltable *llt, struct llentry *lle);
222void lltable_unlink_entry(struct lltable *llt, struct llentry *lle);
223void lltable_fill_sa_entry(const struct llentry *lle, struct sockaddr *sa);
224struct ifnet *lltable_get_ifp(const struct lltable *llt);
225int lltable_get_af(const struct lltable *llt);
226
227int lltable_foreach_lle(struct lltable *llt, llt_foreach_cb_t *f,
228    void *farg);
229/*
230 * Generic link layer address lookup function.
231 */
232static __inline struct llentry *
233lla_lookup(struct lltable *llt, u_int flags, const struct sockaddr *l3addr)
234{
235
236	return (llt->llt_lookup(llt, flags, l3addr));
237}
238
239static __inline struct llentry *
240lla_create(struct lltable *llt, u_int flags, const struct sockaddr *l3addr)
241{
242
243	return (llt->llt_create(llt, flags, l3addr));
244}
245
246static __inline int
247lla_delete(struct lltable *llt, u_int flags, const struct sockaddr *l3addr)
248{
249
250	return (llt->llt_delete(llt, flags, l3addr));
251}
252
253
254int		lla_rt_output(struct rt_msghdr *, struct rt_addrinfo *);
255
256#include <sys/eventhandler.h>
257enum {
258	LLENTRY_RESOLVED,
259	LLENTRY_TIMEDOUT,
260	LLENTRY_DELETED,
261	LLENTRY_EXPIRED,
262};
263typedef void (*lle_event_fn)(void *, struct llentry *, int);
264EVENTHANDLER_DECLARE(lle_event, lle_event_fn);
265#endif  /* _NET_IF_LLATBL_H_ */
266