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