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