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("$FreeBSD$");
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
36 struct ifnet;
37 struct sysctl_req;
38 struct rt_msghdr;
39 struct rt_addrinfo;
40
41 struct llentry;
42 LIST_HEAD(llentries, llentry);
43
44 extern 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 #define LLE_MAX_LINKHDR 24 /* Full IB header */
52 /*
53 * Code referencing llentry must at least hold
54 * a shared lock
55 */
56 struct llentry {
57 LIST_ENTRY(llentry) lle_next;
58 union {
59 struct in_addr addr4;
60 struct in6_addr addr6;
61 } r_l3addr;
62 char r_linkdata[LLE_MAX_LINKHDR]; /* L2 data */
63 uint8_t r_hdrlen; /* length for LL header */
64 uint8_t spare0[3];
65 uint16_t r_flags; /* LLE runtime flags */
66 uint16_t r_skip_req; /* feedback from fast path */
67
68 struct lltable *lle_tbl;
69 struct llentries *lle_head;
70 void (*lle_free)(struct llentry *);
71 struct mbuf *la_hold;
72 int la_numheld; /* # of packets currently held */
73 time_t la_expire;
74 uint16_t la_flags;
75 uint16_t la_asked;
76 uint16_t la_preempt;
77 int16_t ln_state; /* IPv6 has ND6_LLINFO_NOSTATE == -2 */
78 uint16_t ln_router;
79 time_t ln_ntick;
80 time_t lle_remtime; /* Real time remaining */
81 time_t lle_hittime; /* Time when r_skip_req was unset */
82 int lle_refcnt;
83 char *ll_addr; /* link-layer address */
84
85 LIST_ENTRY(llentry) lle_chain; /* chain of deleted items */
86 struct callout lle_timer;
87 struct rwlock lle_lock;
88 struct mtx req_mtx;
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_ADDREF(lle) do { \
110 LLE_WLOCK_ASSERT(lle); \
111 KASSERT((lle)->lle_refcnt >= 0, \
112 ("negative refcnt %d on lle %p", \
113 (lle)->lle_refcnt, (lle))); \
114 (lle)->lle_refcnt++; \
115 } while (0)
116
117 #define LLE_REMREF(lle) do { \
118 LLE_WLOCK_ASSERT(lle); \
119 KASSERT((lle)->lle_refcnt > 0, \
120 ("bogus refcnt %d on lle %p", \
121 (lle)->lle_refcnt, (lle))); \
122 (lle)->lle_refcnt--; \
123 } while (0)
124
125 #define LLE_FREE_LOCKED(lle) do { \
126 if ((lle)->lle_refcnt == 1) \
127 (lle)->lle_free(lle); \
128 else { \
129 LLE_REMREF(lle); \
130 LLE_WUNLOCK(lle); \
131 } \
132 /* guard against invalid refs */ \
133 (lle) = NULL; \
134 } while (0)
135
136 #define LLE_FREE(lle) do { \
137 LLE_WLOCK(lle); \
138 LLE_FREE_LOCKED(lle); \
139 } while (0)
140
141 typedef struct llentry *(llt_lookup_t)(struct lltable *, u_int flags,
142 const struct sockaddr *l3addr);
143 typedef struct llentry *(llt_alloc_t)(struct lltable *, u_int flags,
144 const struct sockaddr *l3addr);
145 typedef void (llt_delete_t)(struct lltable *, struct llentry *);
146 typedef void (llt_prefix_free_t)(struct lltable *,
147 const struct sockaddr *addr, const struct sockaddr *mask, u_int flags);
148 typedef int (llt_dump_entry_t)(struct lltable *, struct llentry *,
149 struct sysctl_req *);
150 typedef uint32_t (llt_hash_t)(const struct llentry *, uint32_t);
151 typedef int (llt_match_prefix_t)(const struct sockaddr *,
152 const struct sockaddr *, u_int, struct llentry *);
153 typedef void (llt_free_entry_t)(struct lltable *, struct llentry *);
154 typedef void (llt_fill_sa_entry_t)(const struct llentry *, struct sockaddr *);
155 typedef void (llt_free_tbl_t)(struct lltable *);
156 typedef void (llt_link_entry_t)(struct lltable *, struct llentry *);
157 typedef void (llt_unlink_entry_t)(struct llentry *);
158 typedef void (llt_mark_used_t)(struct llentry *);
159
160 typedef int (llt_foreach_cb_t)(struct lltable *, struct llentry *, void *);
161 typedef int (llt_foreach_entry_t)(struct lltable *, llt_foreach_cb_t *, void *);
162
163 struct 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_alloc_t *llt_alloc_entry;
172 llt_delete_t *llt_delete_entry;
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 llt_mark_used_t *llt_mark_used;
184 };
185
186 MALLOC_DECLARE(M_LLTABLE);
187
188 /*
189 * LLentry flags
190 */
191 #define LLE_DELETED 0x0001 /* entry must be deleted */
192 #define LLE_STATIC 0x0002 /* entry is static */
193 #define LLE_IFADDR 0x0004 /* entry is interface addr */
194 #define LLE_VALID 0x0008 /* ll_addr is valid */
195 #define LLE_REDIRECT 0x0010 /* installed by redirect; has host rtentry */
196 #define LLE_PUB 0x0020 /* publish entry ??? */
197 #define LLE_LINKED 0x0040 /* linked to lookup structure */
198 /* LLE request flags */
199 #define LLE_EXCLUSIVE 0x2000 /* return lle xlocked */
200 #define LLE_UNLOCKED 0x4000 /* return lle unlocked */
201 #define LLE_ADDRONLY 0x4000 /* return lladdr instead of full header */
202 #define LLE_CREATE 0x8000 /* hint to avoid lle lookup */
203
204 /* LLE flags used by fastpath code */
205 #define RLLE_VALID 0x0001 /* entry is valid */
206 #define RLLE_IFADDR LLE_IFADDR /* entry is ifaddr */
207
208 #define LLATBL_HASH(key, mask) \
209 (((((((key >> 8) ^ key) >> 8) ^ key) >> 8) ^ key) & mask)
210
211 struct lltable *lltable_allocate_htbl(uint32_t hsize);
212 void lltable_free(struct lltable *);
213 void lltable_link(struct lltable *llt);
214 void lltable_prefix_free(int, struct sockaddr *,
215 struct sockaddr *, u_int);
216 #if 0
217 void lltable_drain(int);
218 #endif
219 int lltable_sysctl_dumparp(int, struct sysctl_req *);
220
221 size_t llentry_free(struct llentry *);
222 struct llentry *llentry_alloc(struct ifnet *, struct lltable *,
223 struct sockaddr_storage *);
224
225 /* helper functions */
226 size_t lltable_drop_entry_queue(struct llentry *);
227 void lltable_set_entry_addr(struct ifnet *ifp, struct llentry *lle,
228 const char *linkhdr, size_t linkhdrsize, int lladdr_off);
229 int lltable_try_set_entry_addr(struct ifnet *ifp, struct llentry *lle,
230 const char *linkhdr, size_t linkhdrsize, int lladdr_off);
231
232 int lltable_calc_llheader(struct ifnet *ifp, int family, char *lladdr,
233 char *buf, size_t *bufsize, int *lladdr_off);
234 void lltable_update_ifaddr(struct lltable *llt);
235 struct llentry *lltable_alloc_entry(struct lltable *llt, u_int flags,
236 const struct sockaddr *l4addr);
237 void lltable_free_entry(struct lltable *llt, struct llentry *lle);
238 int lltable_delete_addr(struct lltable *llt, u_int flags,
239 const struct sockaddr *l3addr);
240 void lltable_link_entry(struct lltable *llt, struct llentry *lle);
241 void lltable_unlink_entry(struct lltable *llt, struct llentry *lle);
242 void lltable_fill_sa_entry(const struct llentry *lle, struct sockaddr *sa);
243 struct ifnet *lltable_get_ifp(const struct lltable *llt);
244 int lltable_get_af(const struct lltable *llt);
245
246 int lltable_foreach_lle(struct lltable *llt, llt_foreach_cb_t *f,
247 void *farg);
248 /*
249 * Generic link layer address lookup function.
250 */
251 static __inline struct llentry *
lla_lookup(struct lltable * llt,u_int flags,const struct sockaddr * l3addr)252 lla_lookup(struct lltable *llt, u_int flags, const struct sockaddr *l3addr)
253 {
254
255 return (llt->llt_lookup(llt, flags, l3addr));
256 }
257
258 /*
259 * Notify the LLE code that the entry was used by datapath.
260 */
261 static __inline void
llentry_mark_used(struct llentry * lle)262 llentry_mark_used(struct llentry *lle)
263 {
264
265 if (lle->r_skip_req == 0)
266 return;
267 if ((lle->r_flags & RLLE_VALID) != 0)
268 lle->lle_tbl->llt_mark_used(lle);
269 }
270
271 int lla_rt_output(struct rt_msghdr *, struct rt_addrinfo *);
272
273 #include <sys/eventhandler.h>
274 enum {
275 LLENTRY_RESOLVED,
276 LLENTRY_TIMEDOUT,
277 LLENTRY_DELETED,
278 LLENTRY_EXPIRED,
279 };
280 typedef void (*lle_event_fn)(void *, struct llentry *, int);
281 EVENTHANDLER_DECLARE(lle_event, lle_event_fn);
282 #endif /* _NET_IF_LLATBL_H_ */
283