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) this_cpu_inc((tbl)->stats->field) 92 93 struct neighbour { 94 struct neighbour *next; 95 struct neigh_table *tbl; 96 struct neigh_parms *parms; 97 struct net_device *dev; 98 unsigned long used; 99 unsigned long confirmed; 100 unsigned long updated; 101 __u8 flags; 102 __u8 nud_state; 103 __u8 type; 104 __u8 dead; 105 atomic_t probes; 106 rwlock_t lock; 107 unsigned char ha[ALIGN(MAX_ADDR_LEN, sizeof(unsigned long))]; 108 struct hh_cache *hh; 109 atomic_t refcnt; 110 int (*output)(struct sk_buff *skb); 111 struct sk_buff_head arp_queue; 112 struct timer_list timer; 113 const struct neigh_ops *ops; 114 u8 primary_key[0]; 115 }; 116 117 struct neigh_ops { 118 int family; 119 void (*solicit)(struct neighbour *, struct sk_buff*); 120 void (*error_report)(struct neighbour *, struct sk_buff*); 121 int (*output)(struct sk_buff*); 122 int (*connected_output)(struct sk_buff*); 123 int (*hh_output)(struct sk_buff*); 124 int (*queue_xmit)(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 */ 140 141 142 struct neigh_table { 143 struct neigh_table *next; 144 int family; 145 int entry_size; 146 int key_len; 147 __u32 (*hash)(const void *pkey, const struct net_device *); 148 int (*constructor)(struct neighbour *); 149 int (*pconstructor)(struct pneigh_entry *); 150 void (*pdestructor)(struct pneigh_entry *); 151 void (*proxy_redo)(struct sk_buff *skb); 152 char *id; 153 struct neigh_parms parms; 154 /* HACK. gc_* should follow parms without a gap! */ 155 int gc_interval; 156 int gc_thresh1; 157 int gc_thresh2; 158 int gc_thresh3; 159 unsigned long last_flush; 160 struct delayed_work gc_work; 161 struct timer_list proxy_timer; 162 struct sk_buff_head proxy_queue; 163 atomic_t entries; 164 rwlock_t lock; 165 unsigned long last_rand; 166 struct kmem_cache *kmem_cachep; 167 struct neigh_statistics __percpu *stats; 168 struct neighbour **hash_buckets; 169 unsigned int hash_mask; 170 __u32 hash_rnd; 171 struct pneigh_entry **phash_buckets; 172 }; 173 174 /* flags for neigh_update() */ 175 #define NEIGH_UPDATE_F_OVERRIDE 0x00000001 176 #define NEIGH_UPDATE_F_WEAK_OVERRIDE 0x00000002 177 #define NEIGH_UPDATE_F_OVERRIDE_ISROUTER 0x00000004 178 #define NEIGH_UPDATE_F_ISROUTER 0x40000000 179 #define NEIGH_UPDATE_F_ADMIN 0x80000000 180 181 extern void neigh_table_init(struct neigh_table *tbl); 182 extern void neigh_table_init_no_netlink(struct neigh_table *tbl); 183 extern int neigh_table_clear(struct neigh_table *tbl); 184 extern struct neighbour * neigh_lookup(struct neigh_table *tbl, 185 const void *pkey, 186 struct net_device *dev); 187 extern struct neighbour * neigh_lookup_nodev(struct neigh_table *tbl, 188 struct net *net, 189 const void *pkey); 190 extern struct neighbour * neigh_create(struct neigh_table *tbl, 191 const void *pkey, 192 struct net_device *dev); 193 extern void neigh_destroy(struct neighbour *neigh); 194 extern int __neigh_event_send(struct neighbour *neigh, struct sk_buff *skb); 195 extern int neigh_update(struct neighbour *neigh, const u8 *lladdr, u8 new, 196 u32 flags); 197 extern void neigh_changeaddr(struct neigh_table *tbl, struct net_device *dev); 198 extern int neigh_ifdown(struct neigh_table *tbl, struct net_device *dev); 199 extern int neigh_resolve_output(struct sk_buff *skb); 200 extern int neigh_connected_output(struct sk_buff *skb); 201 extern int neigh_compat_output(struct sk_buff *skb); 202 extern struct neighbour *neigh_event_ns(struct neigh_table *tbl, 203 u8 *lladdr, void *saddr, 204 struct net_device *dev); 205 206 extern struct neigh_parms *neigh_parms_alloc(struct net_device *dev, struct neigh_table *tbl); 207 extern void neigh_parms_release(struct neigh_table *tbl, struct neigh_parms *parms); 208 209 static inline 210 struct net *neigh_parms_net(const struct neigh_parms *parms) 211 { 212 return read_pnet(&parms->net); 213 } 214 215 extern unsigned long neigh_rand_reach_time(unsigned long base); 216 217 extern void pneigh_enqueue(struct neigh_table *tbl, struct neigh_parms *p, 218 struct sk_buff *skb); 219 extern struct pneigh_entry *pneigh_lookup(struct neigh_table *tbl, struct net *net, const void *key, struct net_device *dev, int creat); 220 extern struct pneigh_entry *__pneigh_lookup(struct neigh_table *tbl, 221 struct net *net, 222 const void *key, 223 struct net_device *dev); 224 extern int pneigh_delete(struct neigh_table *tbl, struct net *net, const void *key, struct net_device *dev); 225 226 static inline 227 struct net *pneigh_net(const struct pneigh_entry *pneigh) 228 { 229 return read_pnet(&pneigh->net); 230 } 231 232 extern void neigh_app_ns(struct neighbour *n); 233 extern void neigh_for_each(struct neigh_table *tbl, void (*cb)(struct neighbour *, void *), void *cookie); 234 extern void __neigh_for_each_release(struct neigh_table *tbl, int (*cb)(struct neighbour *)); 235 extern void pneigh_for_each(struct neigh_table *tbl, void (*cb)(struct pneigh_entry *)); 236 237 struct neigh_seq_state { 238 struct seq_net_private p; 239 struct neigh_table *tbl; 240 void *(*neigh_sub_iter)(struct neigh_seq_state *state, 241 struct neighbour *n, loff_t *pos); 242 unsigned int bucket; 243 unsigned int flags; 244 #define NEIGH_SEQ_NEIGH_ONLY 0x00000001 245 #define NEIGH_SEQ_IS_PNEIGH 0x00000002 246 #define NEIGH_SEQ_SKIP_NOARP 0x00000004 247 }; 248 extern void *neigh_seq_start(struct seq_file *, loff_t *, struct neigh_table *, unsigned int); 249 extern void *neigh_seq_next(struct seq_file *, void *, loff_t *); 250 extern void neigh_seq_stop(struct seq_file *, void *); 251 252 extern int neigh_sysctl_register(struct net_device *dev, 253 struct neigh_parms *p, 254 char *p_name, 255 proc_handler *proc_handler); 256 extern void neigh_sysctl_unregister(struct neigh_parms *p); 257 258 static inline void __neigh_parms_put(struct neigh_parms *parms) 259 { 260 atomic_dec(&parms->refcnt); 261 } 262 263 static inline struct neigh_parms *neigh_parms_clone(struct neigh_parms *parms) 264 { 265 atomic_inc(&parms->refcnt); 266 return parms; 267 } 268 269 /* 270 * Neighbour references 271 */ 272 273 static inline void neigh_release(struct neighbour *neigh) 274 { 275 if (atomic_dec_and_test(&neigh->refcnt)) 276 neigh_destroy(neigh); 277 } 278 279 static inline struct neighbour * neigh_clone(struct neighbour *neigh) 280 { 281 if (neigh) 282 atomic_inc(&neigh->refcnt); 283 return neigh; 284 } 285 286 #define neigh_hold(n) atomic_inc(&(n)->refcnt) 287 288 static inline void neigh_confirm(struct neighbour *neigh) 289 { 290 if (neigh) 291 neigh->confirmed = jiffies; 292 } 293 294 static inline int neigh_event_send(struct neighbour *neigh, struct sk_buff *skb) 295 { 296 neigh->used = jiffies; 297 if (!(neigh->nud_state&(NUD_CONNECTED|NUD_DELAY|NUD_PROBE))) 298 return __neigh_event_send(neigh, skb); 299 return 0; 300 } 301 302 #ifdef CONFIG_BRIDGE_NETFILTER 303 static inline int neigh_hh_bridge(struct hh_cache *hh, struct sk_buff *skb) 304 { 305 unsigned seq, hh_alen; 306 307 do { 308 seq = read_seqbegin(&hh->hh_lock); 309 hh_alen = HH_DATA_ALIGN(ETH_HLEN); 310 memcpy(skb->data - hh_alen, hh->hh_data, ETH_ALEN + hh_alen - ETH_HLEN); 311 } while (read_seqretry(&hh->hh_lock, seq)); 312 return 0; 313 } 314 #endif 315 316 static inline int neigh_hh_output(struct hh_cache *hh, struct sk_buff *skb) 317 { 318 unsigned seq; 319 int hh_len; 320 321 do { 322 int hh_alen; 323 324 seq = read_seqbegin(&hh->hh_lock); 325 hh_len = hh->hh_len; 326 hh_alen = HH_DATA_ALIGN(hh_len); 327 memcpy(skb->data - hh_alen, hh->hh_data, hh_alen); 328 } while (read_seqretry(&hh->hh_lock, seq)); 329 330 skb_push(skb, hh_len); 331 return hh->hh_output(skb); 332 } 333 334 static inline struct neighbour * 335 __neigh_lookup(struct neigh_table *tbl, const void *pkey, struct net_device *dev, int creat) 336 { 337 struct neighbour *n = neigh_lookup(tbl, pkey, dev); 338 339 if (n || !creat) 340 return n; 341 342 n = neigh_create(tbl, pkey, dev); 343 return IS_ERR(n) ? NULL : n; 344 } 345 346 static inline struct neighbour * 347 __neigh_lookup_errno(struct neigh_table *tbl, const void *pkey, 348 struct net_device *dev) 349 { 350 struct neighbour *n = neigh_lookup(tbl, pkey, dev); 351 352 if (n) 353 return n; 354 355 return neigh_create(tbl, pkey, dev); 356 } 357 358 struct neighbour_cb { 359 unsigned long sched_next; 360 unsigned int flags; 361 }; 362 363 #define LOCALLY_ENQUEUED 0x1 364 365 #define NEIGH_CB(skb) ((struct neighbour_cb *)(skb)->cb) 366 367 #endif 368