1/*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2004 Luigi Rizzo, Alessandro Cerri. All rights reserved.
5 * Copyright (c) 2004-2008 Qing Li. All rights reserved.
6 * Copyright (c) 2008 Kip Macy. All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29#include <sys/cdefs.h>
30#ifndef	_NET_IF_LLATBL_H_
31#define	_NET_IF_LLATBL_H_
32
33#include <sys/_eventhandler.h>
34#include <sys/_rwlock.h>
35#include <netinet/in.h>
36#include <sys/epoch.h>
37#include <sys/ck.h>
38
39struct ifnet;
40struct sysctl_req;
41struct rt_msghdr;
42struct rt_addrinfo;
43struct llentry;
44CK_LIST_HEAD(llentries, llentry);
45
46#define	LLE_MAX_LINKHDR		24	/* Full IB header */
47/*
48 * Code referencing llentry must at least hold
49 * a shared lock
50 */
51struct llentry {
52	CK_LIST_ENTRY(llentry)	 lle_next;
53	union {
54		struct in_addr	addr4;
55		struct in6_addr	addr6;
56	} r_l3addr;
57	char			r_linkdata[LLE_MAX_LINKHDR]; /* L2 data */
58	uint8_t			r_hdrlen;	/* length for LL header */
59	uint8_t			r_family;	/* Upper layer proto family */
60	uint8_t			spare0[2];
61	uint16_t		r_flags;	/* LLE runtime flags */
62	uint16_t		r_skip_req;	/* feedback from fast path */
63
64	struct lltable		 *lle_tbl;
65	struct llentries	 *lle_head;
66	void			(*lle_free)(struct llentry *);
67	struct mbuf		 *la_hold;
68	int			 la_numheld;  /* # of packets currently held */
69	time_t			 la_expire;
70	uint16_t		 la_flags;
71	uint16_t		 la_asked;
72	uint16_t		 la_preempt;
73	int16_t			 ln_state;	/* IPv6 has ND6_LLINFO_NOSTATE == -2 */
74	uint16_t		 ln_router;
75	time_t			 ln_ntick;
76	time_t			lle_remtime;	/* Real time remaining */
77	time_t			lle_hittime;	/* Time when r_skip_req was unset */
78	int			 lle_refcnt;
79	char			*ll_addr;	/* link-layer address */
80	CK_SLIST_HEAD(llentry_children_head,llentry)	lle_children;	/* child encaps */
81	CK_SLIST_ENTRY(llentry)	lle_child_next;	/* child encaps */
82	struct llentry		*lle_parent;	/* parent for a child */
83
84	CK_LIST_ENTRY(llentry)	lle_chain;	/* chain of deleted items */
85	struct callout		lle_timer;
86	struct rwlock		 lle_lock;
87	struct mtx		req_mtx;
88	struct epoch_context lle_epoch_ctx;
89};
90
91#define	LLE_WLOCK(lle)		rw_wlock(&(lle)->lle_lock)
92#define	LLE_RLOCK(lle)		rw_rlock(&(lle)->lle_lock)
93#define	LLE_WUNLOCK(lle)	rw_wunlock(&(lle)->lle_lock)
94#define	LLE_RUNLOCK(lle)	rw_runlock(&(lle)->lle_lock)
95#define	LLE_DOWNGRADE(lle)	rw_downgrade(&(lle)->lle_lock)
96#define	LLE_TRY_UPGRADE(lle)	rw_try_upgrade(&(lle)->lle_lock)
97#define	LLE_LOCK_INIT(lle)	rw_init_flags(&(lle)->lle_lock, "lle", RW_DUPOK)
98#define	LLE_LOCK_DESTROY(lle)	rw_destroy(&(lle)->lle_lock)
99#define	LLE_WLOCK_ASSERT(lle)	rw_assert(&(lle)->lle_lock, RA_WLOCKED)
100
101#define	LLE_REQ_INIT(lle)	mtx_init(&(lle)->req_mtx, "lle req", \
102	NULL, MTX_DEF)
103#define	LLE_REQ_DESTROY(lle)	mtx_destroy(&(lle)->req_mtx)
104#define	LLE_REQ_LOCK(lle)	mtx_lock(&(lle)->req_mtx)
105#define	LLE_REQ_UNLOCK(lle)	mtx_unlock(&(lle)->req_mtx)
106
107#define LLE_IS_VALID(lle)	(((lle) != NULL) && ((lle) != (void *)-1))
108
109#define	LLE_SF(_fam, _flags)	(((_flags) & 0xFFFF) | ((_fam) << 16))
110
111#define	LLE_ADDREF(lle) do {					\
112	LLE_WLOCK_ASSERT(lle);					\
113	KASSERT((lle)->lle_refcnt >= 0,				\
114	    ("negative refcnt %d on lle %p",			\
115	    (lle)->lle_refcnt, (lle)));				\
116	(lle)->lle_refcnt++;					\
117} while (0)
118
119#define	LLE_REMREF(lle)	do {					\
120	LLE_WLOCK_ASSERT(lle);					\
121	KASSERT((lle)->lle_refcnt > 0,				\
122	    ("bogus refcnt %d on lle %p",			\
123	    (lle)->lle_refcnt, (lle)));				\
124	(lle)->lle_refcnt--;					\
125} while (0)
126
127#define	LLE_FREE_LOCKED(lle) do {				\
128	if ((lle)->lle_refcnt == 1)				\
129		(lle)->lle_free(lle);				\
130	else {							\
131		LLE_REMREF(lle);				\
132		LLE_WUNLOCK(lle);				\
133	}							\
134	/* guard against invalid refs */			\
135	(lle) = NULL;						\
136} while (0)
137
138#define	LLE_FREE(lle) do {					\
139	LLE_WLOCK(lle);						\
140	LLE_FREE_LOCKED(lle);					\
141} while (0)
142
143typedef	struct llentry *(llt_lookup_t)(struct lltable *, u_int flags,
144    const struct sockaddr *l3addr);
145typedef	struct llentry *(llt_alloc_t)(struct lltable *, u_int flags,
146    const struct sockaddr *l3addr);
147typedef	void (llt_delete_t)(struct lltable *, struct llentry *);
148typedef void (llt_prefix_free_t)(struct lltable *,
149    const struct sockaddr *addr, const struct sockaddr *mask, u_int flags);
150typedef int (llt_dump_entry_t)(struct lltable *, struct llentry *,
151    struct sysctl_req *);
152typedef uint32_t (llt_hash_t)(const struct llentry *, uint32_t);
153typedef int (llt_match_prefix_t)(const struct sockaddr *,
154    const struct sockaddr *, u_int, struct llentry *);
155typedef void (llt_free_entry_t)(struct lltable *, struct llentry *);
156typedef void (llt_fill_sa_entry_t)(const struct llentry *, struct sockaddr *);
157typedef void (llt_free_tbl_t)(struct lltable *);
158typedef int (llt_link_entry_t)(struct lltable *, struct llentry *);
159typedef int (llt_unlink_entry_t)(struct llentry *);
160typedef void (llt_mark_used_t)(struct llentry *);
161typedef void (llt_post_resolved_t)(struct lltable *, struct llentry *);
162
163typedef int (llt_foreach_cb_t)(struct lltable *, struct llentry *, void *);
164typedef int (llt_foreach_entry_t)(struct lltable *, llt_foreach_cb_t *, void *);
165typedef bool (llt_match_cb_t)(struct lltable *, struct llentry *, void *);
166
167struct lltable {
168	SLIST_ENTRY(lltable)	llt_link;
169	sa_family_t		llt_af;
170	uint8_t			llt_flags;
171	uint8_t			llt_spare[2];
172	int			llt_hsize;
173	int			llt_entries;
174	int			llt_maxentries;
175	struct llentries	*lle_head;
176	struct ifnet		*llt_ifp;
177
178	llt_lookup_t		*llt_lookup;
179	llt_alloc_t		*llt_alloc_entry;
180	llt_delete_t		*llt_delete_entry;
181	llt_prefix_free_t	*llt_prefix_free;
182	llt_dump_entry_t	*llt_dump_entry;
183	llt_hash_t		*llt_hash;
184	llt_match_prefix_t	*llt_match_prefix;
185	llt_free_entry_t	*llt_free_entry;
186	llt_foreach_entry_t	*llt_foreach_entry;
187	llt_link_entry_t	*llt_link_entry;
188	llt_unlink_entry_t	*llt_unlink_entry;
189	llt_fill_sa_entry_t	*llt_fill_sa_entry;
190	llt_free_tbl_t		*llt_free_tbl;
191	llt_mark_used_t		*llt_mark_used;
192	llt_post_resolved_t	*llt_post_resolved;
193};
194
195MALLOC_DECLARE(M_LLTABLE);
196
197/*
198 * LLtable flags
199 */
200#define	LLT_ADDEDPROXY	0x01	/* added a proxy llentry */
201
202/*
203 * LLentry flags
204 */
205#define	LLE_DELETED	0x0001	/* entry must be deleted */
206#define	LLE_STATIC	0x0002	/* entry is static */
207#define	LLE_IFADDR	0x0004	/* entry is interface addr */
208#define	LLE_VALID	0x0008	/* ll_addr is valid */
209#define	LLE_REDIRECT	0x0010	/* installed by redirect; has host rtentry */
210#define	LLE_PUB		0x0020	/* publish entry ??? */
211#define	LLE_LINKED	0x0040	/* linked to lookup structure */
212#define	LLE_CHILD	0x0080	/* Child LLE storing different AF encap */
213/* LLE request flags */
214#define	LLE_EXCLUSIVE	0x2000	/* return lle xlocked  */
215#define	LLE_UNLOCKED	0x4000	/* return lle unlocked */
216#define	LLE_ADDRONLY	0x4000	/* return lladdr instead of full header */
217#define	LLE_CREATE	0x8000	/* hint to avoid lle lookup */
218
219/* LLE flags used by fastpath code */
220#define	RLLE_VALID	0x0001		/* entry is valid */
221#define	RLLE_IFADDR	LLE_IFADDR	/* entry is ifaddr */
222
223#define LLATBL_HASH(key, mask) \
224	(((((((key >> 8) ^ key) >> 8) ^ key) >> 8) ^ key) & mask)
225
226struct lltable *lltable_allocate_htbl(uint32_t hsize);
227void		lltable_free(struct lltable *);
228void		lltable_link(struct lltable *llt);
229void		lltable_prefix_free(int, struct sockaddr *,
230		    struct sockaddr *, u_int);
231int		lltable_sysctl_dumparp(int, struct sysctl_req *);
232size_t		lltable_append_entry_queue(struct llentry *,
233		    struct mbuf *, size_t);
234
235struct lltable *in_lltable_get(struct ifnet *ifp);
236struct lltable *in6_lltable_get(struct ifnet *ifp);
237struct lltable *lltable_get(struct ifnet *ifp, int family);
238
239size_t		llentry_free(struct llentry *);
240
241/* helper functions */
242size_t lltable_drop_entry_queue(struct llentry *);
243void lltable_set_entry_addr(struct ifnet *ifp, struct llentry *lle,
244    const char *linkhdr, size_t linkhdrsize, int lladdr_off);
245int lltable_try_set_entry_addr(struct ifnet *ifp, struct llentry *lle,
246    const char *linkhdr, size_t linkhdrsize, int lladdr_off);
247
248int lltable_calc_llheader(struct ifnet *ifp, int family, char *lladdr,
249    char *buf, size_t *bufsize, int *lladdr_off);
250void lltable_update_ifaddr(struct lltable *llt);
251struct llentry *lltable_alloc_entry(struct lltable *llt, u_int flags,
252    const struct sockaddr *l4addr);
253void lltable_free_entry(struct lltable *llt, struct llentry *lle);
254int lltable_delete_addr(struct lltable *llt, u_int flags,
255    const struct sockaddr *l3addr);
256int lltable_link_entry(struct lltable *llt, struct llentry *lle);
257int lltable_unlink_entry(struct lltable *llt, struct llentry *lle);
258void lltable_link_child_entry(struct llentry *parent_lle, struct llentry *child_lle);
259void lltable_unlink_child_entry(struct llentry *child_lle);
260void lltable_fill_sa_entry(const struct llentry *lle, struct sockaddr *sa);
261struct ifnet *lltable_get_ifp(const struct lltable *llt);
262int lltable_get_af(const struct lltable *llt);
263
264bool lltable_acquire_wlock(struct ifnet *ifp, struct llentry *lle);
265
266int lltable_foreach_lle(struct lltable *llt, llt_foreach_cb_t *f,
267    void *farg);
268void lltable_delete_conditional(struct lltable *llt, llt_match_cb_t *func,
269    void *farg);
270
271/*
272 * Generic link layer address lookup function.
273 */
274static __inline struct llentry *
275lla_lookup(struct lltable *llt, u_int flags, const struct sockaddr *l3addr)
276{
277
278	return (llt->llt_lookup(llt, flags, l3addr));
279}
280
281void llentry_request_feedback(struct llentry *lle);
282void llentry_mark_used(struct llentry *lle);
283time_t llentry_get_hittime(struct llentry *lle);
284int llentry_get_upper_family(const struct llentry *lle, int default_family);
285
286/*
287 * Notify the LLE code that the entry was used by datapath.
288 */
289static __inline void
290llentry_provide_feedback(struct llentry *lle)
291{
292
293	if (__predict_true(lle->r_skip_req == 0))
294		return;
295	llentry_mark_used(lle);
296}
297struct llentry *llentry_lookup_family(struct llentry *lle, int family);
298
299int		lla_rt_output(struct rt_msghdr *, struct rt_addrinfo *);
300
301enum {
302	LLENTRY_RESOLVED,
303	LLENTRY_TIMEDOUT,
304	LLENTRY_DELETED,
305	LLENTRY_EXPIRED,
306};
307typedef void (*lle_event_fn)(void *, struct llentry *, int);
308EVENTHANDLER_DECLARE(lle_event, lle_event_fn);
309#endif  /* _NET_IF_LLATBL_H_ */
310