if_llatbl.h revision 287798 
1224145Sdim/*
2224145Sdim * 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 287798 2015-09-14 19:17:25Z vangyzen $");
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	struct callout		lle_timer;
86	struct rwlock		 lle_lock;
87};
88
89#define	LLE_WLOCK(lle)		rw_wlock(&(lle)->lle_lock)
90#define	LLE_RLOCK(lle)		rw_rlock(&(lle)->lle_lock)
91#define	LLE_WUNLOCK(lle)	rw_wunlock(&(lle)->lle_lock)
92#define	LLE_RUNLOCK(lle)	rw_runlock(&(lle)->lle_lock)
93#define	LLE_DOWNGRADE(lle)	rw_downgrade(&(lle)->lle_lock)
94#define	LLE_TRY_UPGRADE(lle)	rw_try_upgrade(&(lle)->lle_lock)
95#define	LLE_LOCK_INIT(lle)	rw_init_flags(&(lle)->lle_lock, "lle", RW_DUPOK)
96#define	LLE_LOCK_DESTROY(lle)	rw_destroy(&(lle)->lle_lock)
97#define	LLE_WLOCK_ASSERT(lle)	rw_assert(&(lle)->lle_lock, RA_WLOCKED)
98
99#define LLE_IS_VALID(lle)	(((lle) != NULL) && ((lle) != (void *)-1))
100
101#define	LLE_ADDREF(lle) do {					\
102	LLE_WLOCK_ASSERT(lle);					\
103	KASSERT((lle)->lle_refcnt >= 0,				\
104	    ("negative refcnt %d on lle %p",			\
105	    (lle)->lle_refcnt, (lle)));				\
106	(lle)->lle_refcnt++;					\
107} while (0)
108
109#define	LLE_REMREF(lle)	do {					\
110	LLE_WLOCK_ASSERT(lle);					\
111	KASSERT((lle)->lle_refcnt > 0,				\
112	    ("bogus refcnt %d on lle %p",			\
113	    (lle)->lle_refcnt, (lle)));				\
114	(lle)->lle_refcnt--;					\
115} while (0)
116
117#define	LLE_FREE_LOCKED(lle) do {				\
118	if ((lle)->lle_refcnt == 1)				\
119		(lle)->lle_free(lle);				\
120	else {							\
121		LLE_REMREF(lle);				\
122		LLE_WUNLOCK(lle);				\
123	}							\
124	/* guard against invalid refs */			\
125	(lle) = NULL;						\
126} while (0)
127
128#define	LLE_FREE(lle) do {					\
129	LLE_WLOCK(lle);						\
130	LLE_FREE_LOCKED(lle);					\
131} while (0)
132
133
134typedef	struct llentry *(llt_lookup_t)(struct lltable *, u_int flags,
135    const struct sockaddr *l3addr);
136typedef	struct llentry *(llt_alloc_t)(struct lltable *, u_int flags,
137    const struct sockaddr *l3addr);
138typedef	void (llt_delete_t)(struct lltable *, struct llentry *);
139typedef void (llt_prefix_free_t)(struct lltable *,
140    const struct sockaddr *addr, const struct sockaddr *mask, u_int flags);
141typedef int (llt_dump_entry_t)(struct lltable *, struct llentry *,
142    struct sysctl_req *);
143typedef uint32_t (llt_hash_t)(const struct llentry *, uint32_t);
144typedef int (llt_match_prefix_t)(const struct sockaddr *,
145    const struct sockaddr *, u_int, struct llentry *);
146typedef void (llt_free_entry_t)(struct lltable *, struct llentry *);
147typedef void (llt_fill_sa_entry_t)(const struct llentry *, struct sockaddr *);
148typedef void (llt_free_tbl_t)(struct lltable *);
149typedef void (llt_link_entry_t)(struct lltable *, struct llentry *);
150typedef void (llt_unlink_entry_t)(struct llentry *);
151
152typedef int (llt_foreach_cb_t)(struct lltable *, struct llentry *, void *);
153typedef int (llt_foreach_entry_t)(struct lltable *, llt_foreach_cb_t *, void *);
154
155struct lltable {
156	SLIST_ENTRY(lltable)	llt_link;
157	int			llt_af;
158	int			llt_hsize;
159	struct llentries	*lle_head;
160	struct ifnet		*llt_ifp;
161
162	llt_lookup_t		*llt_lookup;
163	llt_alloc_t		*llt_alloc_entry;
164	llt_delete_t		*llt_delete_entry;
165	llt_prefix_free_t	*llt_prefix_free;
166	llt_dump_entry_t	*llt_dump_entry;
167	llt_hash_t		*llt_hash;
168	llt_match_prefix_t	*llt_match_prefix;
169	llt_free_entry_t	*llt_free_entry;
170	llt_foreach_entry_t	*llt_foreach_entry;
171	llt_link_entry_t	*llt_link_entry;
172	llt_unlink_entry_t	*llt_unlink_entry;
173	llt_fill_sa_entry_t	*llt_fill_sa_entry;
174	llt_free_tbl_t		*llt_free_tbl;
175};
176
177MALLOC_DECLARE(M_LLTABLE);
178
179/*
180 * LLentry flags
181 */
182#define	LLE_DELETED	0x0001	/* entry must be deleted */
183#define	LLE_STATIC	0x0002	/* entry is static */
184#define	LLE_IFADDR	0x0004	/* entry is interface addr */
185#define	LLE_VALID	0x0008	/* ll_addr is valid */
186#define	LLE_REDIRECT	0x0010	/* installed by redirect; has host rtentry */
187#define	LLE_PUB		0x0020	/* publish entry ??? */
188#define	LLE_LINKED	0x0040	/* linked to lookup structure */
189/* LLE request flags */
190#define	LLE_EXCLUSIVE	0x2000	/* return lle xlocked  */
191
192#define LLATBL_HASH(key, mask) \
193	(((((((key >> 8) ^ key) >> 8) ^ key) >> 8) ^ key) & mask)
194
195struct lltable *lltable_allocate_htbl(uint32_t hsize);
196void		lltable_free(struct lltable *);
197void		lltable_link(struct lltable *llt);
198void		lltable_prefix_free(int, struct sockaddr *,
199		    struct sockaddr *, u_int);
200#if 0
201void		lltable_drain(int);
202#endif
203int		lltable_sysctl_dumparp(int, struct sysctl_req *);
204
205size_t		llentry_free(struct llentry *);
206struct llentry  *llentry_alloc(struct ifnet *, struct lltable *,
207		    struct sockaddr_storage *);
208
209/* helper functions */
210size_t lltable_drop_entry_queue(struct llentry *);
211
212struct llentry *lltable_alloc_entry(struct lltable *llt, u_int flags,
213    const struct sockaddr *l4addr);
214void lltable_free_entry(struct lltable *llt, struct llentry *lle);
215int lltable_delete_addr(struct lltable *llt, u_int flags,
216    const struct sockaddr *l3addr);
217void lltable_link_entry(struct lltable *llt, struct llentry *lle);
218void lltable_unlink_entry(struct lltable *llt, struct llentry *lle);
219void lltable_fill_sa_entry(const struct llentry *lle, struct sockaddr *sa);
220struct ifnet *lltable_get_ifp(const struct lltable *llt);
221int lltable_get_af(const struct lltable *llt);
222
223int lltable_foreach_lle(struct lltable *llt, llt_foreach_cb_t *f,
224    void *farg);
225/*
226 * Generic link layer address lookup function.
227 */
228static __inline struct llentry *
229lla_lookup(struct lltable *llt, u_int flags, const struct sockaddr *l3addr)
230{
231
232	return (llt->llt_lookup(llt, flags, l3addr));
233}
234
235int		lla_rt_output(struct rt_msghdr *, struct rt_addrinfo *);
236
237#include <sys/eventhandler.h>
238enum {
239	LLENTRY_RESOLVED,
240	LLENTRY_TIMEDOUT,
241	LLENTRY_DELETED,
242	LLENTRY_EXPIRED,
243};
244typedef void (*lle_event_fn)(void *, struct llentry *, int);
245EVENTHANDLER_DECLARE(lle_event, lle_event_fn);
246#endif  /* _NET_IF_LLATBL_H_ */
247