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
39 struct ifnet;
40 struct sysctl_req;
41 struct rt_msghdr;
42 struct rt_addrinfo;
43 struct llentry;
44 CK_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 */
51 struct 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
143 typedef struct llentry *(llt_lookup_t)(struct lltable *, u_int flags,
144 const struct sockaddr *l3addr);
145 typedef struct llentry *(llt_alloc_t)(struct lltable *, u_int flags,
146 const struct sockaddr *l3addr);
147 typedef void (llt_delete_t)(struct lltable *, struct llentry *);
148 typedef void (llt_prefix_free_t)(struct lltable *,
149 const struct sockaddr *addr, const struct sockaddr *mask, u_int flags);
150 typedef int (llt_dump_entry_t)(struct lltable *, struct llentry *,
151 struct sysctl_req *);
152 typedef uint32_t (llt_hash_t)(const struct llentry *, uint32_t);
153 typedef int (llt_match_prefix_t)(const struct sockaddr *,
154 const struct sockaddr *, u_int, struct llentry *);
155 typedef void (llt_free_entry_t)(struct lltable *, struct llentry *);
156 typedef void (llt_fill_sa_entry_t)(const struct llentry *, struct sockaddr *);
157 typedef void (llt_free_tbl_t)(struct lltable *);
158 typedef int (llt_link_entry_t)(struct lltable *, struct llentry *);
159 typedef int (llt_unlink_entry_t)(struct llentry *);
160 typedef void (llt_mark_used_t)(struct llentry *);
161 typedef void (llt_post_resolved_t)(struct lltable *, struct llentry *);
162
163 typedef int (llt_foreach_cb_t)(struct lltable *, struct llentry *, void *);
164 typedef int (llt_foreach_entry_t)(struct lltable *, llt_foreach_cb_t *, void *);
165 typedef bool (llt_match_cb_t)(struct lltable *, struct llentry *, void *);
166
167 struct 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
195 MALLOC_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
226 struct lltable *lltable_allocate_htbl(uint32_t hsize);
227 void lltable_free(struct lltable *);
228 void lltable_link(struct lltable *llt);
229 void lltable_prefix_free(int, struct sockaddr *,
230 struct sockaddr *, u_int);
231 int lltable_sysctl_dumparp(int, struct sysctl_req *);
232 size_t lltable_append_entry_queue(struct llentry *,
233 struct mbuf *, size_t);
234
235 struct lltable *in_lltable_get(struct ifnet *ifp);
236 struct lltable *in6_lltable_get(struct ifnet *ifp);
237 struct lltable *lltable_get(struct ifnet *ifp, int family);
238
239 size_t llentry_free(struct llentry *);
240
241 /* helper functions */
242 size_t lltable_drop_entry_queue(struct llentry *);
243 void lltable_set_entry_addr(struct ifnet *ifp, struct llentry *lle,
244 const char *linkhdr, size_t linkhdrsize, int lladdr_off);
245 int lltable_try_set_entry_addr(struct ifnet *ifp, struct llentry *lle,
246 const char *linkhdr, size_t linkhdrsize, int lladdr_off);
247
248 int lltable_calc_llheader(struct ifnet *ifp, int family, char *lladdr,
249 char *buf, size_t *bufsize, int *lladdr_off);
250 void lltable_update_ifaddr(struct lltable *llt);
251 struct llentry *lltable_alloc_entry(struct lltable *llt, u_int flags,
252 const struct sockaddr *l4addr);
253 void lltable_free_entry(struct lltable *llt, struct llentry *lle);
254 int lltable_delete_addr(struct lltable *llt, u_int flags,
255 const struct sockaddr *l3addr);
256 int lltable_link_entry(struct lltable *llt, struct llentry *lle);
257 int lltable_unlink_entry(struct lltable *llt, struct llentry *lle);
258 void lltable_link_child_entry(struct llentry *parent_lle, struct llentry *child_lle);
259 void lltable_unlink_child_entry(struct llentry *child_lle);
260 void lltable_fill_sa_entry(const struct llentry *lle, struct sockaddr *sa);
261 struct ifnet *lltable_get_ifp(const struct lltable *llt);
262 int lltable_get_af(const struct lltable *llt);
263
264 bool lltable_acquire_wlock(struct ifnet *ifp, struct llentry *lle);
265
266 int lltable_foreach_lle(struct lltable *llt, llt_foreach_cb_t *f,
267 void *farg);
268 void lltable_delete_conditional(struct lltable *llt, llt_match_cb_t *func,
269 void *farg);
270
271 /*
272 * Generic link layer address lookup function.
273 */
274 static __inline struct llentry *
lla_lookup(struct lltable * llt,u_int flags,const struct sockaddr * l3addr)275 lla_lookup(struct lltable *llt, u_int flags, const struct sockaddr *l3addr)
276 {
277
278 return (llt->llt_lookup(llt, flags, l3addr));
279 }
280
281 void llentry_request_feedback(struct llentry *lle);
282 void llentry_mark_used(struct llentry *lle);
283 time_t llentry_get_hittime(struct llentry *lle);
284 int 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 */
289 static __inline void
llentry_provide_feedback(struct llentry * lle)290 llentry_provide_feedback(struct llentry *lle)
291 {
292
293 if (__predict_true(lle->r_skip_req == 0))
294 return;
295 llentry_mark_used(lle);
296 }
297 struct llentry *llentry_lookup_family(struct llentry *lle, int family);
298
299 int lla_rt_output(struct rt_msghdr *, struct rt_addrinfo *);
300
301 enum {
302 LLENTRY_RESOLVED,
303 LLENTRY_TIMEDOUT,
304 LLENTRY_DELETED,
305 LLENTRY_EXPIRED,
306 };
307 typedef void (*lle_event_fn)(void *, struct llentry *, int);
308 EVENTHANDLER_DECLARE(lle_event, lle_event_fn);
309 #endif /* _NET_IF_LLATBL_H_ */
310