blob: eb21340a573b4906d267a18bf69bbf37bdebb8b4 [file] [log] [blame]
#include <linux/neighbour.h>
* Generic neighbour manipulation
* Authors:
* Pedro Roque <>
* Alexey Kuznetsov <>
* Changes:
* Harald Welte: <>
* - Add neighbour cache statistics like rtstat
#include <asm/atomic.h>
#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include <linux/rcupdate.h>
#include <linux/seq_file.h>
#include <linux/err.h>
#include <linux/sysctl.h>
#include <linux/workqueue.h>
#include <net/rtnetlink.h>
* NUD stands for "neighbor unreachability detection"
struct neighbour;
struct neigh_parms {
struct net *net;
struct net_device *dev;
struct neigh_parms *next;
int (*neigh_setup)(struct neighbour *);
void (*neigh_cleanup)(struct neighbour *);
struct neigh_table *tbl;
void *sysctl_table;
int dead;
atomic_t refcnt;
struct rcu_head rcu_head;
int base_reachable_time;
int retrans_time;
int gc_staletime;
int reachable_time;
int delay_probe_time;
int queue_len;
int ucast_probes;
int app_probes;
int mcast_probes;
int anycast_delay;
int proxy_delay;
int proxy_qlen;
int locktime;
struct neigh_statistics {
unsigned long allocs; /* number of allocated neighs */
unsigned long destroys; /* number of destroyed neighs */
unsigned long hash_grows; /* number of hash resizes */
unsigned long res_failed; /* number of failed resolutions */
unsigned long lookups; /* number of lookups */
unsigned long hits; /* number of hits (among lookups) */
unsigned long rcv_probes_mcast; /* number of received mcast ipv6 */
unsigned long rcv_probes_ucast; /* number of received ucast ipv6 */
unsigned long periodic_gc_runs; /* number of periodic GC runs */
unsigned long forced_gc_runs; /* number of forced GC runs */
unsigned long unres_discards; /* number of unresolved drops */
#define NEIGH_CACHE_STAT_INC(tbl, field) this_cpu_inc((tbl)->stats->field)
struct neighbour {
struct neighbour *next;
struct neigh_table *tbl;
struct neigh_parms *parms;
struct net_device *dev;
unsigned long used;
unsigned long confirmed;
unsigned long updated;
__u8 flags;
__u8 nud_state;
__u8 type;
__u8 dead;
atomic_t probes;
rwlock_t lock;
unsigned char ha[ALIGN(MAX_ADDR_LEN, sizeof(unsigned long))];
struct hh_cache *hh;
atomic_t refcnt;
int (*output)(struct sk_buff *skb);
struct sk_buff_head arp_queue;
struct timer_list timer;
const struct neigh_ops *ops;
u8 primary_key[0];
struct neigh_ops {
int family;
void (*solicit)(struct neighbour *, struct sk_buff*);
void (*error_report)(struct neighbour *, struct sk_buff*);
int (*output)(struct sk_buff*);
int (*connected_output)(struct sk_buff*);
int (*hh_output)(struct sk_buff*);
int (*queue_xmit)(struct sk_buff*);
struct pneigh_entry {
struct pneigh_entry *next;
struct net *net;
struct net_device *dev;
u8 flags;
u8 key[0];
* neighbour table manipulation
struct neigh_table {
struct neigh_table *next;
int family;
int entry_size;
int key_len;
__u32 (*hash)(const void *pkey, const struct net_device *);
int (*constructor)(struct neighbour *);
int (*pconstructor)(struct pneigh_entry *);
void (*pdestructor)(struct pneigh_entry *);
void (*proxy_redo)(struct sk_buff *skb);
char *id;
struct neigh_parms parms;
/* HACK. gc_* shoul follow parms without a gap! */
int gc_interval;
int gc_thresh1;
int gc_thresh2;
int gc_thresh3;
unsigned long last_flush;
struct delayed_work gc_work;
struct timer_list proxy_timer;
struct sk_buff_head proxy_queue;
atomic_t entries;
rwlock_t lock;
unsigned long last_rand;
struct kmem_cache *kmem_cachep;
struct neigh_statistics __percpu *stats;
struct neighbour **hash_buckets;
unsigned int hash_mask;
__u32 hash_rnd;
struct pneigh_entry **phash_buckets;
/* flags for neigh_update() */
#define NEIGH_UPDATE_F_OVERRIDE 0x00000001
#define NEIGH_UPDATE_F_ISROUTER 0x40000000
#define NEIGH_UPDATE_F_ADMIN 0x80000000
extern void neigh_table_init(struct neigh_table *tbl);
extern void neigh_table_init_no_netlink(struct neigh_table *tbl);
extern int neigh_table_clear(struct neigh_table *tbl);
extern struct neighbour * neigh_lookup(struct neigh_table *tbl,
const void *pkey,
struct net_device *dev);
extern struct neighbour * neigh_lookup_nodev(struct neigh_table *tbl,
struct net *net,
const void *pkey);
extern struct neighbour * neigh_create(struct neigh_table *tbl,
const void *pkey,
struct net_device *dev);
extern void neigh_destroy(struct neighbour *neigh);
extern int __neigh_event_send(struct neighbour *neigh, struct sk_buff *skb);
extern int neigh_update(struct neighbour *neigh, const u8 *lladdr, u8 new,
u32 flags);
extern void neigh_changeaddr(struct neigh_table *tbl, struct net_device *dev);
extern int neigh_ifdown(struct neigh_table *tbl, struct net_device *dev);
extern int neigh_resolve_output(struct sk_buff *skb);
extern int neigh_connected_output(struct sk_buff *skb);
extern int neigh_compat_output(struct sk_buff *skb);
extern struct neighbour *neigh_event_ns(struct neigh_table *tbl,
u8 *lladdr, void *saddr,
struct net_device *dev);
extern struct neigh_parms *neigh_parms_alloc(struct net_device *dev, struct neigh_table *tbl);
extern void neigh_parms_release(struct neigh_table *tbl, struct neigh_parms *parms);
static inline
struct net *neigh_parms_net(const struct neigh_parms *parms)
return read_pnet(&parms->net);
extern unsigned long neigh_rand_reach_time(unsigned long base);
extern void pneigh_enqueue(struct neigh_table *tbl, struct neigh_parms *p,
struct sk_buff *skb);
extern struct pneigh_entry *pneigh_lookup(struct neigh_table *tbl, struct net *net, const void *key, struct net_device *dev, int creat);
extern struct pneigh_entry *__pneigh_lookup(struct neigh_table *tbl,
struct net *net,
const void *key,
struct net_device *dev);
extern int pneigh_delete(struct neigh_table *tbl, struct net *net, const void *key, struct net_device *dev);
static inline
struct net *pneigh_net(const struct pneigh_entry *pneigh)
return read_pnet(&pneigh->net);
extern void neigh_app_ns(struct neighbour *n);
extern void neigh_for_each(struct neigh_table *tbl, void (*cb)(struct neighbour *, void *), void *cookie);
extern void __neigh_for_each_release(struct neigh_table *tbl, int (*cb)(struct neighbour *));
extern void pneigh_for_each(struct neigh_table *tbl, void (*cb)(struct pneigh_entry *));
struct neigh_seq_state {
struct seq_net_private p;
struct neigh_table *tbl;
void *(*neigh_sub_iter)(struct neigh_seq_state *state,
struct neighbour *n, loff_t *pos);
unsigned int bucket;
unsigned int flags;
#define NEIGH_SEQ_NEIGH_ONLY 0x00000001
#define NEIGH_SEQ_IS_PNEIGH 0x00000002
#define NEIGH_SEQ_SKIP_NOARP 0x00000004
extern void *neigh_seq_start(struct seq_file *, loff_t *, struct neigh_table *, unsigned int);
extern void *neigh_seq_next(struct seq_file *, void *, loff_t *);
extern void neigh_seq_stop(struct seq_file *, void *);
extern int neigh_sysctl_register(struct net_device *dev,
struct neigh_parms *p,
char *p_name,
proc_handler *proc_handler);
extern void neigh_sysctl_unregister(struct neigh_parms *p);
static inline void __neigh_parms_put(struct neigh_parms *parms)
static inline struct neigh_parms *neigh_parms_clone(struct neigh_parms *parms)
return parms;
* Neighbour references
static inline void neigh_release(struct neighbour *neigh)
if (atomic_dec_and_test(&neigh->refcnt))
static inline struct neighbour * neigh_clone(struct neighbour *neigh)
if (neigh)
return neigh;
#define neigh_hold(n) atomic_inc(&(n)->refcnt)
static inline void neigh_confirm(struct neighbour *neigh)
if (neigh)
neigh->confirmed = jiffies;
static inline int neigh_event_send(struct neighbour *neigh, struct sk_buff *skb)
neigh->used = jiffies;
if (!(neigh->nud_state&(NUD_CONNECTED|NUD_DELAY|NUD_PROBE)))
return __neigh_event_send(neigh, skb);
return 0;
static inline int neigh_hh_bridge(struct hh_cache *hh, struct sk_buff *skb)
unsigned seq, hh_alen;
do {
seq = read_seqbegin(&hh->hh_lock);
memcpy(skb->data - hh_alen, hh->hh_data, ETH_ALEN + hh_alen - ETH_HLEN);
} while (read_seqretry(&hh->hh_lock, seq));
return 0;
static inline int neigh_hh_output(struct hh_cache *hh, struct sk_buff *skb)
unsigned seq;
int hh_len;
do {
int hh_alen;
seq = read_seqbegin(&hh->hh_lock);
hh_len = hh->hh_len;
hh_alen = HH_DATA_ALIGN(hh_len);
memcpy(skb->data - hh_alen, hh->hh_data, hh_alen);
} while (read_seqretry(&hh->hh_lock, seq));
skb_push(skb, hh_len);
return hh->hh_output(skb);
static inline struct neighbour *
__neigh_lookup(struct neigh_table *tbl, const void *pkey, struct net_device *dev, int creat)
struct neighbour *n = neigh_lookup(tbl, pkey, dev);
if (n || !creat)
return n;
n = neigh_create(tbl, pkey, dev);
return IS_ERR(n) ? NULL : n;
static inline struct neighbour *
__neigh_lookup_errno(struct neigh_table *tbl, const void *pkey,
struct net_device *dev)
struct neighbour *n = neigh_lookup(tbl, pkey, dev);
if (n)
return n;
return neigh_create(tbl, pkey, dev);
struct neighbour_cb {
unsigned long sched_next;
unsigned int flags;
#define NEIGH_CB(skb) ((struct neighbour_cb *)(skb)->cb)