1 #ifndef _NET_NEIGHBOUR_H 2 #define _NET_NEIGHBOUR_H 3 4 #include <linux/neighbour.h> 5 6 /* 7 * Generic neighbour manipulation 8 * 9 * Authors: 10 * Pedro Roque <roque@di.fc.ul.pt> 11 * Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> 12 * 13 * Changes: 14 * 15 * Harald Welte: <laforge@gnumonks.org> 16 * - Add neighbour cache statistics like rtstat 17 */ 18 19 #include <linux/atomic.h> 20 #include <linux/netdevice.h> 21 #include <linux/skbuff.h> 22 #include <linux/rcupdate.h> 23 #include <linux/seq_file.h> 24 25 #include <linux/err.h> 26 #include <linux/sysctl.h> 27 #include <linux/workqueue.h> 28 #include <net/rtnetlink.h> 29 30 /* 31 * NUD stands for "neighbor unreachability detection" 32 */ 33 34 #define NUD_IN_TIMER (NUD_INCOMPLETE|NUD_REACHABLE|NUD_DELAY|NUD_PROBE) 35 #define NUD_VALID (NUD_PERMANENT|NUD_NOARP|NUD_REACHABLE|NUD_PROBE|NUD_STALE|NUD_DELAY) 36 #define NUD_CONNECTED (NUD_PERMANENT|NUD_NOARP|NUD_REACHABLE) 37 38 struct neighbour; 39 40 struct neigh_parms { 41 #ifdef CONFIG_NET_NS 42 struct net *net; 43 #endif 44 struct net_device *dev; 45 struct neigh_parms *next; 46 void (*neigh_cleanup)(struct neighbour *); 47 struct neigh_table *tbl; 48 49 void *sysctl_table; 50 51 int dead; 52 atomic_t refcnt; 53 struct rcu_head rcu_head; 54 55 int base_reachable_time; 56 int retrans_time; 57 int gc_staletime; 58 int reachable_time; 59 int delay_probe_time; 60 61 int queue_len_bytes; 62 int ucast_probes; 63 int app_probes; 64 int mcast_probes; 65 int anycast_delay; 66 int proxy_delay; 67 int proxy_qlen; 68 int locktime; 69 }; 70 71 struct neigh_statistics { 72 unsigned long allocs; /* number of allocated neighs */ 73 unsigned long destroys; /* number of destroyed neighs */ 74 unsigned long hash_grows; /* number of hash resizes */ 75 76 unsigned long res_failed; /* number of failed resolutions */ 77 78 unsigned long lookups; /* number of lookups */ 79 unsigned long hits; /* number of hits (among lookups) */ 80 81 unsigned long rcv_probes_mcast; /* number of received mcast ipv6 */ 82 unsigned long rcv_probes_ucast; /* number of received ucast ipv6 */ 83 84 unsigned long periodic_gc_runs; /* number of periodic GC runs */ 85 unsigned long forced_gc_runs; /* number of forced GC runs */ 86 87 unsigned long unres_discards; /* number of unresolved drops */ 88 }; 89 90 #define NEIGH_CACHE_STAT_INC(tbl, field) this_cpu_inc((tbl)->stats->field) 91 92 struct neighbour { 93 struct neighbour __rcu *next; 94 struct neigh_table *tbl; 95 struct neigh_parms *parms; 96 unsigned long confirmed; 97 unsigned long updated; 98 rwlock_t lock; 99 atomic_t refcnt; 100 struct sk_buff_head arp_queue; 101 unsigned int arp_queue_len_bytes; 102 struct timer_list timer; 103 unsigned long used; 104 atomic_t probes; 105 __u8 flags; 106 __u8 nud_state; 107 __u8 type; 108 __u8 dead; 109 seqlock_t ha_lock; 110 unsigned char ha[ALIGN(MAX_ADDR_LEN, sizeof(unsigned long))]; 111 struct hh_cache hh; 112 int (*output)(struct neighbour *, struct sk_buff *); 113 const struct neigh_ops *ops; 114 struct rcu_head rcu; 115 struct net_device *dev; 116 u8 primary_key[0]; 117 }; 118 119 struct neigh_ops { 120 int family; 121 void (*solicit)(struct neighbour *, struct sk_buff *); 122 void (*error_report)(struct neighbour *, struct sk_buff *); 123 int (*output)(struct neighbour *, struct sk_buff *); 124 int (*connected_output)(struct neighbour *, struct sk_buff *); 125 }; 126 127 struct pneigh_entry { 128 struct pneigh_entry *next; 129 #ifdef CONFIG_NET_NS 130 struct net *net; 131 #endif 132 struct net_device *dev; 133 u8 flags; 134 u8 key[0]; 135 }; 136 137 /* 138 * neighbour table manipulation 139 */ 140 141 struct neigh_hash_table { 142 struct neighbour __rcu **hash_buckets; 143 unsigned int hash_shift; 144 __u32 hash_rnd; 145 struct rcu_head rcu; 146 }; 147 148 149 struct neigh_table { 150 struct neigh_table *next; 151 int family; 152 int entry_size; 153 int key_len; 154 __u32 (*hash)(const void *pkey, 155 const struct net_device *dev, 156 __u32 hash_rnd); 157 int (*constructor)(struct neighbour *); 158 int (*pconstructor)(struct pneigh_entry *); 159 void (*pdestructor)(struct pneigh_entry *); 160 void (*proxy_redo)(struct sk_buff *skb); 161 char *id; 162 struct neigh_parms parms; 163 /* HACK. gc_* should follow parms without a gap! */ 164 int gc_interval; 165 int gc_thresh1; 166 int gc_thresh2; 167 int gc_thresh3; 168 unsigned long last_flush; 169 struct delayed_work gc_work; 170 struct timer_list proxy_timer; 171 struct sk_buff_head proxy_queue; 172 atomic_t entries; 173 rwlock_t lock; 174 unsigned long last_rand; 175 struct neigh_statistics __percpu *stats; 176 struct neigh_hash_table __rcu *nht; 177 struct pneigh_entry **phash_buckets; 178 }; 179 180 #define NEIGH_PRIV_ALIGN sizeof(long long) 181 182 static inline void *neighbour_priv(const struct neighbour *n) 183 { 184 return (char *)n + ALIGN(sizeof(*n) + n->tbl->key_len, NEIGH_PRIV_ALIGN); 185 } 186 187 /* flags for neigh_update() */ 188 #define NEIGH_UPDATE_F_OVERRIDE 0x00000001 189 #define NEIGH_UPDATE_F_WEAK_OVERRIDE 0x00000002 190 #define NEIGH_UPDATE_F_OVERRIDE_ISROUTER 0x00000004 191 #define NEIGH_UPDATE_F_ISROUTER 0x40000000 192 #define NEIGH_UPDATE_F_ADMIN 0x80000000 193 194 extern void neigh_table_init(struct neigh_table *tbl); 195 extern void neigh_table_init_no_netlink(struct neigh_table *tbl); 196 extern int neigh_table_clear(struct neigh_table *tbl); 197 extern struct neighbour * neigh_lookup(struct neigh_table *tbl, 198 const void *pkey, 199 struct net_device *dev); 200 extern struct neighbour * neigh_lookup_nodev(struct neigh_table *tbl, 201 struct net *net, 202 const void *pkey); 203 extern struct neighbour * neigh_create(struct neigh_table *tbl, 204 const void *pkey, 205 struct net_device *dev); 206 extern void neigh_destroy(struct neighbour *neigh); 207 extern int __neigh_event_send(struct neighbour *neigh, struct sk_buff *skb); 208 extern int neigh_update(struct neighbour *neigh, const u8 *lladdr, u8 new, 209 u32 flags); 210 extern void neigh_changeaddr(struct neigh_table *tbl, struct net_device *dev); 211 extern int neigh_ifdown(struct neigh_table *tbl, struct net_device *dev); 212 extern int neigh_resolve_output(struct neighbour *neigh, struct sk_buff *skb); 213 extern int neigh_connected_output(struct neighbour *neigh, struct sk_buff *skb); 214 extern int neigh_compat_output(struct neighbour *neigh, struct sk_buff *skb); 215 extern int neigh_direct_output(struct neighbour *neigh, struct sk_buff *skb); 216 extern struct neighbour *neigh_event_ns(struct neigh_table *tbl, 217 u8 *lladdr, void *saddr, 218 struct net_device *dev); 219 220 extern struct neigh_parms *neigh_parms_alloc(struct net_device *dev, struct neigh_table *tbl); 221 extern void neigh_parms_release(struct neigh_table *tbl, struct neigh_parms *parms); 222 223 static inline 224 struct net *neigh_parms_net(const struct neigh_parms *parms) 225 { 226 return read_pnet(&parms->net); 227 } 228 229 extern unsigned long neigh_rand_reach_time(unsigned long base); 230 231 extern void pneigh_enqueue(struct neigh_table *tbl, struct neigh_parms *p, 232 struct sk_buff *skb); 233 extern struct pneigh_entry *pneigh_lookup(struct neigh_table *tbl, struct net *net, const void *key, struct net_device *dev, int creat); 234 extern struct pneigh_entry *__pneigh_lookup(struct neigh_table *tbl, 235 struct net *net, 236 const void *key, 237 struct net_device *dev); 238 extern int pneigh_delete(struct neigh_table *tbl, struct net *net, const void *key, struct net_device *dev); 239 240 static inline 241 struct net *pneigh_net(const struct pneigh_entry *pneigh) 242 { 243 return read_pnet(&pneigh->net); 244 } 245 246 extern void neigh_app_ns(struct neighbour *n); 247 extern void neigh_for_each(struct neigh_table *tbl, void (*cb)(struct neighbour *, void *), void *cookie); 248 extern void __neigh_for_each_release(struct neigh_table *tbl, int (*cb)(struct neighbour *)); 249 extern void pneigh_for_each(struct neigh_table *tbl, void (*cb)(struct pneigh_entry *)); 250 251 struct neigh_seq_state { 252 struct seq_net_private p; 253 struct neigh_table *tbl; 254 struct neigh_hash_table *nht; 255 void *(*neigh_sub_iter)(struct neigh_seq_state *state, 256 struct neighbour *n, loff_t *pos); 257 unsigned int bucket; 258 unsigned int flags; 259 #define NEIGH_SEQ_NEIGH_ONLY 0x00000001 260 #define NEIGH_SEQ_IS_PNEIGH 0x00000002 261 #define NEIGH_SEQ_SKIP_NOARP 0x00000004 262 }; 263 extern void *neigh_seq_start(struct seq_file *, loff_t *, struct neigh_table *, unsigned int); 264 extern void *neigh_seq_next(struct seq_file *, void *, loff_t *); 265 extern void neigh_seq_stop(struct seq_file *, void *); 266 267 extern int neigh_sysctl_register(struct net_device *dev, 268 struct neigh_parms *p, 269 char *p_name, 270 proc_handler *proc_handler); 271 extern void neigh_sysctl_unregister(struct neigh_parms *p); 272 273 static inline void __neigh_parms_put(struct neigh_parms *parms) 274 { 275 atomic_dec(&parms->refcnt); 276 } 277 278 static inline struct neigh_parms *neigh_parms_clone(struct neigh_parms *parms) 279 { 280 atomic_inc(&parms->refcnt); 281 return parms; 282 } 283 284 /* 285 * Neighbour references 286 */ 287 288 static inline void neigh_release(struct neighbour *neigh) 289 { 290 if (atomic_dec_and_test(&neigh->refcnt)) 291 neigh_destroy(neigh); 292 } 293 294 static inline struct neighbour * neigh_clone(struct neighbour *neigh) 295 { 296 if (neigh) 297 atomic_inc(&neigh->refcnt); 298 return neigh; 299 } 300 301 #define neigh_hold(n) atomic_inc(&(n)->refcnt) 302 303 static inline void neigh_confirm(struct neighbour *neigh) 304 { 305 if (neigh) 306 neigh->confirmed = jiffies; 307 } 308 309 static inline int neigh_event_send(struct neighbour *neigh, struct sk_buff *skb) 310 { 311 unsigned long now = jiffies; 312 313 if (neigh->used != now) 314 neigh->used = now; 315 if (!(neigh->nud_state&(NUD_CONNECTED|NUD_DELAY|NUD_PROBE))) 316 return __neigh_event_send(neigh, skb); 317 return 0; 318 } 319 320 #ifdef CONFIG_BRIDGE_NETFILTER 321 static inline int neigh_hh_bridge(struct hh_cache *hh, struct sk_buff *skb) 322 { 323 unsigned seq, hh_alen; 324 325 do { 326 seq = read_seqbegin(&hh->hh_lock); 327 hh_alen = HH_DATA_ALIGN(ETH_HLEN); 328 memcpy(skb->data - hh_alen, hh->hh_data, ETH_ALEN + hh_alen - ETH_HLEN); 329 } while (read_seqretry(&hh->hh_lock, seq)); 330 return 0; 331 } 332 #endif 333 334 static inline int neigh_hh_output(struct hh_cache *hh, struct sk_buff *skb) 335 { 336 unsigned seq; 337 int hh_len; 338 339 do { 340 int hh_alen; 341 342 seq = read_seqbegin(&hh->hh_lock); 343 hh_len = hh->hh_len; 344 hh_alen = HH_DATA_ALIGN(hh_len); 345 memcpy(skb->data - hh_alen, hh->hh_data, hh_alen); 346 } while (read_seqretry(&hh->hh_lock, seq)); 347 348 skb_push(skb, hh_len); 349 return dev_queue_xmit(skb); 350 } 351 352 static inline int neigh_output(struct neighbour *n, struct sk_buff *skb) 353 { 354 struct hh_cache *hh = &n->hh; 355 if ((n->nud_state & NUD_CONNECTED) && hh->hh_len) 356 return neigh_hh_output(hh, skb); 357 else 358 return n->output(n, skb); 359 } 360 361 static inline struct neighbour * 362 __neigh_lookup(struct neigh_table *tbl, const void *pkey, struct net_device *dev, int creat) 363 { 364 struct neighbour *n = neigh_lookup(tbl, pkey, dev); 365 366 if (n || !creat) 367 return n; 368 369 n = neigh_create(tbl, pkey, dev); 370 return IS_ERR(n) ? NULL : n; 371 } 372 373 static inline struct neighbour * 374 __neigh_lookup_errno(struct neigh_table *tbl, const void *pkey, 375 struct net_device *dev) 376 { 377 struct neighbour *n = neigh_lookup(tbl, pkey, dev); 378 379 if (n) 380 return n; 381 382 return neigh_create(tbl, pkey, dev); 383 } 384 385 struct neighbour_cb { 386 unsigned long sched_next; 387 unsigned int flags; 388 }; 389 390 #define LOCALLY_ENQUEUED 0x1 391 392 #define NEIGH_CB(skb) ((struct neighbour_cb *)(skb)->cb) 393 394 static inline void neigh_ha_snapshot(char *dst, const struct neighbour *n, 395 const struct net_device *dev) 396 { 397 unsigned int seq; 398 399 do { 400 seq = read_seqbegin(&n->ha_lock); 401 memcpy(dst, n->ha, dev->addr_len); 402 } while (read_seqretry(&n->ha_lock, seq)); 403 } 404 #endif 405