[mirror_ubuntu-bionic-kernel.git] / include / net / neighbour.h

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _NET_NEIGHBOUR_H
#define _NET_NEIGHBOUR_H

#include <linux/neighbour.h>

/*
 *	Generic neighbour manipulation
 *
 *	Authors:
 *	Pedro Roque		<roque@di.fc.ul.pt>
 *	Alexey Kuznetsov	<kuznet@ms2.inr.ac.ru>
 *
 * 	Changes:
 *
 *	Harald Welte:		<laforge@gnumonks.org>
 *		- Add neighbour cache statistics like rtstat
 */

#include <linux/atomic.h>
#include <linux/refcount.h>
#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include <linux/rcupdate.h>
#include <linux/seq_file.h>
#include <linux/bitmap.h>

#include <linux/err.h>
#include <linux/sysctl.h>
#include <linux/workqueue.h>
#include <net/rtnetlink.h>

/*
 * NUD stands for "neighbor unreachability detection"
 */

#define NUD_IN_TIMER	(NUD_INCOMPLETE|NUD_REACHABLE|NUD_DELAY|NUD_PROBE)
#define NUD_VALID	(NUD_PERMANENT|NUD_NOARP|NUD_REACHABLE|NUD_PROBE|NUD_STALE|NUD_DELAY)
#define NUD_CONNECTED	(NUD_PERMANENT|NUD_NOARP|NUD_REACHABLE)

struct neighbour;

enum {
	NEIGH_VAR_MCAST_PROBES,
	NEIGH_VAR_UCAST_PROBES,
	NEIGH_VAR_APP_PROBES,
	NEIGH_VAR_MCAST_REPROBES,
	NEIGH_VAR_RETRANS_TIME,
	NEIGH_VAR_BASE_REACHABLE_TIME,
	NEIGH_VAR_DELAY_PROBE_TIME,
	NEIGH_VAR_GC_STALETIME,
	NEIGH_VAR_QUEUE_LEN_BYTES,
	NEIGH_VAR_PROXY_QLEN,
	NEIGH_VAR_ANYCAST_DELAY,
	NEIGH_VAR_PROXY_DELAY,
	NEIGH_VAR_LOCKTIME,
#define NEIGH_VAR_DATA_MAX (NEIGH_VAR_LOCKTIME + 1)
	/* Following are used as a second way to access one of the above */
	NEIGH_VAR_QUEUE_LEN, /* same data as NEIGH_VAR_QUEUE_LEN_BYTES */
	NEIGH_VAR_RETRANS_TIME_MS, /* same data as NEIGH_VAR_RETRANS_TIME */
	NEIGH_VAR_BASE_REACHABLE_TIME_MS, /* same data as NEIGH_VAR_BASE_REACHABLE_TIME */
	/* Following are used by "default" only */
	NEIGH_VAR_GC_INTERVAL,
	NEIGH_VAR_GC_THRESH1,
	NEIGH_VAR_GC_THRESH2,
	NEIGH_VAR_GC_THRESH3,
	NEIGH_VAR_MAX
};

struct neigh_parms {
	possible_net_t net;
	struct net_device *dev;
	struct list_head list;
	int	(*neigh_setup)(struct neighbour *);
	void	(*neigh_cleanup)(struct neighbour *);
	struct neigh_table *tbl;

	void	*sysctl_table;

	int dead;
	refcount_t refcnt;
	struct rcu_head rcu_head;

	int	reachable_time;
	int	data[NEIGH_VAR_DATA_MAX];
	DECLARE_BITMAP(data_state, NEIGH_VAR_DATA_MAX);
};

static inline void neigh_var_set(struct neigh_parms *p, int index, int val)
{
	set_bit(index, p->data_state);
	p->data[index] = val;
}

#define NEIGH_VAR(p, attr) ((p)->data[NEIGH_VAR_ ## attr])

/* In ndo_neigh_setup, NEIGH_VAR_INIT should be used.
 * In other cases, NEIGH_VAR_SET should be used.
 */
#define NEIGH_VAR_INIT(p, attr, val) (NEIGH_VAR(p, attr) = val)
#define NEIGH_VAR_SET(p, attr, val) neigh_var_set(p, NEIGH_VAR_ ## attr, val)

static inline void neigh_parms_data_state_setall(struct neigh_parms *p)
{
	bitmap_fill(p->data_state, NEIGH_VAR_DATA_MAX);
}

static inline void neigh_parms_data_state_cleanall(struct neigh_parms *p)
{
	bitmap_zero(p->data_state, NEIGH_VAR_DATA_MAX);
}

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 */
	unsigned long table_fulls;      /* times even gc couldn't help */
};

#define NEIGH_CACHE_STAT_INC(tbl, field) this_cpu_inc((tbl)->stats->field)

struct neighbour {
	struct neighbour __rcu	*next;
	struct neigh_table	*tbl;
	struct neigh_parms	*parms;
	unsigned long		confirmed;
	unsigned long		updated;
	rwlock_t		lock;
	refcount_t		refcnt;
	struct sk_buff_head	arp_queue;
	unsigned int		arp_queue_len_bytes;
	struct timer_list	timer;
	unsigned long		used;
	atomic_t		probes;
	__u8			flags;
	__u8			nud_state;
	__u8			type;
	__u8			dead;
	seqlock_t		ha_lock;
	unsigned char		ha[ALIGN(MAX_ADDR_LEN, sizeof(unsigned long))];
	struct hh_cache		hh;
	int			(*output)(struct neighbour *, struct sk_buff *);
	const struct neigh_ops	*ops;
	struct rcu_head		rcu;
	struct net_device	*dev;
	u8			primary_key[0];
} __randomize_layout;

struct neigh_ops {
	int			family;
	void			(*solicit)(struct neighbour *, struct sk_buff *);
	void			(*error_report)(struct neighbour *, struct sk_buff *);
	int			(*output)(struct neighbour *, struct sk_buff *);
	int			(*connected_output)(struct neighbour *, struct sk_buff *);
};

struct pneigh_entry {
	struct pneigh_entry	*next;
	possible_net_t		net;
	struct net_device	*dev;
	u8			flags;
	u8			key[0];
};

/*
 *	neighbour table manipulation
 */

#define NEIGH_NUM_HASH_RND	4

struct neigh_hash_table {
	struct neighbour __rcu	**hash_buckets;
	unsigned int		hash_shift;
	__u32			hash_rnd[NEIGH_NUM_HASH_RND];
	struct rcu_head		rcu;
};


struct neigh_table {
	int			family;
	unsigned int		entry_size;
	unsigned int		key_len;
	__be16			protocol;
	__u32			(*hash)(const void *pkey,
					const struct net_device *dev,
					__u32 *hash_rnd);
	bool			(*key_eq)(const struct neighbour *, const void *pkey);
	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;
	struct list_head	parms_list;
	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 neigh_statistics	__percpu *stats;
	struct neigh_hash_table __rcu *nht;
	struct pneigh_entry	**phash_buckets;
};

enum {
	NEIGH_ARP_TABLE = 0,
	NEIGH_ND_TABLE = 1,
	NEIGH_DN_TABLE = 2,
	NEIGH_NR_TABLES,
	NEIGH_LINK_TABLE = NEIGH_NR_TABLES /* Pseudo table for neigh_xmit */
};

static inline int neigh_parms_family(struct neigh_parms *p)
{
	return p->tbl->family;
}

#define NEIGH_PRIV_ALIGN	sizeof(long long)
#define NEIGH_ENTRY_SIZE(size)	ALIGN((size), NEIGH_PRIV_ALIGN)

static inline void *neighbour_priv(const struct neighbour *n)
{
	return (char *)n + n->tbl->entry_size;
}

/* flags for neigh_update() */
#define NEIGH_UPDATE_F_OVERRIDE			0x00000001
#define NEIGH_UPDATE_F_WEAK_OVERRIDE		0x00000002
#define NEIGH_UPDATE_F_OVERRIDE_ISROUTER	0x00000004
#define NEIGH_UPDATE_F_ISROUTER			0x40000000
#define NEIGH_UPDATE_F_ADMIN			0x80000000


static inline bool neigh_key_eq16(const struct neighbour *n, const void *pkey)
{
	return *(const u16 *)n->primary_key == *(const u16 *)pkey;
}

static inline bool neigh_key_eq32(const struct neighbour *n, const void *pkey)
{
	return *(const u32 *)n->primary_key == *(const u32 *)pkey;
}

static inline bool neigh_key_eq128(const struct neighbour *n, const void *pkey)
{
	const u32 *n32 = (const u32 *)n->primary_key;
	const u32 *p32 = pkey;

	return ((n32[0] ^ p32[0]) | (n32[1] ^ p32[1]) |
		(n32[2] ^ p32[2]) | (n32[3] ^ p32[3])) == 0;
}

static inline struct neighbour *___neigh_lookup_noref(
	struct neigh_table *tbl,
	bool (*key_eq)(const struct neighbour *n, const void *pkey),
	__u32 (*hash)(const void *pkey,
		      const struct net_device *dev,
		      __u32 *hash_rnd),
	const void *pkey,
	struct net_device *dev)
{
	struct neigh_hash_table *nht = rcu_dereference_bh(tbl->nht);
	struct neighbour *n;
	u32 hash_val;

	hash_val = hash(pkey, dev, nht->hash_rnd) >> (32 - nht->hash_shift);
	for (n = rcu_dereference_bh(nht->hash_buckets[hash_val]);
	     n != NULL;
	     n = rcu_dereference_bh(n->next)) {
		if (n->dev == dev && key_eq(n, pkey))
			return n;
	}

	return NULL;
}

static inline struct neighbour *__neigh_lookup_noref(struct neigh_table *tbl,
						     const void *pkey,
						     struct net_device *dev)
{
	return ___neigh_lookup_noref(tbl, tbl->key_eq, tbl->hash, pkey, dev);
}

void neigh_table_init(int index, struct neigh_table *tbl);
int neigh_table_clear(int index, struct neigh_table *tbl);
struct neighbour *neigh_lookup(struct neigh_table *tbl, const void *pkey,
			       struct net_device *dev);
struct neighbour *neigh_lookup_nodev(struct neigh_table *tbl, struct net *net,
				     const void *pkey);
struct neighbour *__neigh_create(struct neigh_table *tbl, const void *pkey,
				 struct net_device *dev, bool want_ref);
static inline struct neighbour *neigh_create(struct neigh_table *tbl,
					     const void *pkey,
					     struct net_device *dev)
{
	return __neigh_create(tbl, pkey, dev, true);
}
void neigh_destroy(struct neighbour *neigh);
int __neigh_event_send(struct neighbour *neigh, struct sk_buff *skb);
int neigh_update(struct neighbour *neigh, const u8 *lladdr, u8 new, u32 flags,
		 u32 nlmsg_pid);
void __neigh_set_probe_once(struct neighbour *neigh);
bool neigh_remove_one(struct neighbour *ndel, struct neigh_table *tbl);
void neigh_changeaddr(struct neigh_table *tbl, struct net_device *dev);
int neigh_ifdown(struct neigh_table *tbl, struct net_device *dev);
int neigh_resolve_output(struct neighbour *neigh, struct sk_buff *skb);
int neigh_connected_output(struct neighbour *neigh, struct sk_buff *skb);
int neigh_direct_output(struct neighbour *neigh, struct sk_buff *skb);
struct neighbour *neigh_event_ns(struct neigh_table *tbl,
						u8 *lladdr, void *saddr,
						struct net_device *dev);

struct neigh_parms *neigh_parms_alloc(struct net_device *dev,
				      struct neigh_table *tbl);
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);
}

unsigned long neigh_rand_reach_time(unsigned long base);

void pneigh_enqueue(struct neigh_table *tbl, struct neigh_parms *p,
		    struct sk_buff *skb);
struct pneigh_entry *pneigh_lookup(struct neigh_table *tbl, struct net *net,
				   const void *key, struct net_device *dev,
				   int creat);
struct pneigh_entry *__pneigh_lookup(struct neigh_table *tbl, struct net *net,
				     const void *key, struct net_device *dev);
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);
}

void neigh_app_ns(struct neighbour *n);
void neigh_for_each(struct neigh_table *tbl,
		    void (*cb)(struct neighbour *, void *), void *cookie);
void __neigh_for_each_release(struct neigh_table *tbl,
			      int (*cb)(struct neighbour *));
int neigh_xmit(int fam, struct net_device *, const void *, struct sk_buff *);
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;
	struct neigh_hash_table *nht;
	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
};
void *neigh_seq_start(struct seq_file *, loff_t *, struct neigh_table *,
		      unsigned int);
void *neigh_seq_next(struct seq_file *, void *, loff_t *);
void neigh_seq_stop(struct seq_file *, void *);

int neigh_proc_dointvec(struct ctl_table *ctl, int write,
			void __user *buffer, size_t *lenp, loff_t *ppos);
int neigh_proc_dointvec_jiffies(struct ctl_table *ctl, int write,
				void __user *buffer,
				size_t *lenp, loff_t *ppos);
int neigh_proc_dointvec_ms_jiffies(struct ctl_table *ctl, int write,
				   void __user *buffer,
				   size_t *lenp, loff_t *ppos);

int neigh_sysctl_register(struct net_device *dev, struct neigh_parms *p,
			  proc_handler *proc_handler);
void neigh_sysctl_unregister(struct neigh_parms *p);

static inline void __neigh_parms_put(struct neigh_parms *parms)
{
	refcount_dec(&parms->refcnt);
}

static inline struct neigh_parms *neigh_parms_clone(struct neigh_parms *parms)
{
	refcount_inc(&parms->refcnt);
	return parms;
}

/*
 *	Neighbour references
 */

static inline void neigh_release(struct neighbour *neigh)
{
	if (refcount_dec_and_test(&neigh->refcnt))
		neigh_destroy(neigh);
}

static inline struct neighbour * neigh_clone(struct neighbour *neigh)
{
	if (neigh)
		refcount_inc(&neigh->refcnt);
	return neigh;
}

#define neigh_hold(n)	refcount_inc(&(n)->refcnt)

static inline int neigh_event_send(struct neighbour *neigh, struct sk_buff *skb)
{
	unsigned long now = jiffies;
	
	if (READ_ONCE(neigh->used) != now)
		WRITE_ONCE(neigh->used, now);
	if (!(neigh->nud_state&(NUD_CONNECTED|NUD_DELAY|NUD_PROBE)))
		return __neigh_event_send(neigh, skb);
	return 0;
}

#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
static inline int neigh_hh_bridge(struct hh_cache *hh, struct sk_buff *skb)
{
	unsigned int seq, hh_alen;

	do {
		seq = read_seqbegin(&hh->hh_lock);
		hh_alen = HH_DATA_ALIGN(ETH_HLEN);
		memcpy(skb->data - hh_alen, hh->hh_data, ETH_ALEN + hh_alen - ETH_HLEN);
	} while (read_seqretry(&hh->hh_lock, seq));
	return 0;
}
#endif

static inline int neigh_hh_output(const struct hh_cache *hh, struct sk_buff *skb)
{
	unsigned int hh_alen = 0;
	unsigned int seq;
	unsigned int hh_len;

	do {
		seq = read_seqbegin(&hh->hh_lock);
		hh_len = hh->hh_len;
		if (likely(hh_len <= HH_DATA_MOD)) {
			hh_alen = HH_DATA_MOD;

			/* skb_push() would proceed silently if we have room for
			 * the unaligned size but not for the aligned size:
			 * check headroom explicitly.
			 */
			if (likely(skb_headroom(skb) >= HH_DATA_MOD)) {
				/* this is inlined by gcc */
				memcpy(skb->data - HH_DATA_MOD, hh->hh_data,
				       HH_DATA_MOD);
			}
		} else {
			hh_alen = HH_DATA_ALIGN(hh_len);

			if (likely(skb_headroom(skb) >= hh_alen)) {
				memcpy(skb->data - hh_alen, hh->hh_data,
				       hh_alen);
			}
		}
	} while (read_seqretry(&hh->hh_lock, seq));

	if (WARN_ON_ONCE(skb_headroom(skb) < hh_alen)) {
		kfree_skb(skb);
		return NET_XMIT_DROP;
	}

	__skb_push(skb, hh_len);
	return dev_queue_xmit(skb);
}

static inline int neigh_output(struct neighbour *n, struct sk_buff *skb)
{
	const struct hh_cache *hh = &n->hh;

	if ((n->nud_state & NUD_CONNECTED) && hh->hh_len)
		return neigh_hh_output(hh, skb);
	else
		return n->output(n, 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 LOCALLY_ENQUEUED 0x1

#define NEIGH_CB(skb)	((struct neighbour_cb *)(skb)->cb)

static inline void neigh_ha_snapshot(char *dst, const struct neighbour *n,
				     const struct net_device *dev)
{
	unsigned int seq;

	do {
		seq = read_seqbegin(&n->ha_lock);
		memcpy(dst, n->ha, dev->addr_len);
	} while (read_seqretry(&n->ha_lock, seq));
}


#endif
Commit	Line	Data
b2441318	1	/* SPDX-License-Identifier: GPL-2.0 */
1da177e4 LT	2	#ifndef _NET_NEIGHBOUR_H
	3	#define _NET_NEIGHBOUR_H
	4
9067c722 TG	5	#include <linux/neighbour.h>
9067c722 TG	6
1da177e4 LT	7	/*
	8	* Generic neighbour manipulation
	9	*
	10	* Authors:
	11	* Pedro Roque <roque@di.fc.ul.pt>
	12	* Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
	13	*
	14	* Changes:
	15	*
	16	* Harald Welte: <laforge@gnumonks.org>
	17	* - Add neighbour cache statistics like rtstat
	18	*/
	19
60063497	20	#include <linux/atomic.h>
9f237430	21	#include <linux/refcount.h>
1da177e4	22	#include <linux/netdevice.h>
14c85021	23	#include <linux/skbuff.h>
1da177e4 LT	24	#include <linux/rcupdate.h>
1da177e4 LT	25	#include <linux/seq_file.h>
1d4c8c29	26	#include <linux/bitmap.h>
1da177e4 LT	27
	28	#include <linux/err.h>
	29	#include <linux/sysctl.h>
e4c4e448	30	#include <linux/workqueue.h>
c8822a4e	31	#include <net/rtnetlink.h>
1da177e4	32
39971554 PE	33	/*
	34	* NUD stands for "neighbor unreachability detection"
	35	*/
	36
1da177e4 LT	37	#define NUD_IN_TIMER (NUD_INCOMPLETE\|NUD_REACHABLE\|NUD_DELAY\|NUD_PROBE)
	38	#define NUD_VALID (NUD_PERMANENT\|NUD_NOARP\|NUD_REACHABLE\|NUD_PROBE\|NUD_STALE\|NUD_DELAY)
	39	#define NUD_CONNECTED (NUD_PERMANENT\|NUD_NOARP\|NUD_REACHABLE)
	40
	41	struct neighbour;
	42
1f9248e5 JP	43	enum {
	44	NEIGH_VAR_MCAST_PROBES,
	45	NEIGH_VAR_UCAST_PROBES,
	46	NEIGH_VAR_APP_PROBES,
8da86466	47	NEIGH_VAR_MCAST_REPROBES,
1f9248e5 JP	48	NEIGH_VAR_RETRANS_TIME,
	49	NEIGH_VAR_BASE_REACHABLE_TIME,
	50	NEIGH_VAR_DELAY_PROBE_TIME,
	51	NEIGH_VAR_GC_STALETIME,
	52	NEIGH_VAR_QUEUE_LEN_BYTES,
	53	NEIGH_VAR_PROXY_QLEN,
	54	NEIGH_VAR_ANYCAST_DELAY,
	55	NEIGH_VAR_PROXY_DELAY,
	56	NEIGH_VAR_LOCKTIME,
	57	#define NEIGH_VAR_DATA_MAX (NEIGH_VAR_LOCKTIME + 1)
	58	/* Following are used as a second way to access one of the above */
	59	NEIGH_VAR_QUEUE_LEN, /* same data as NEIGH_VAR_QUEUE_LEN_BYTES */
	60	NEIGH_VAR_RETRANS_TIME_MS, /* same data as NEIGH_VAR_RETRANS_TIME */
	61	NEIGH_VAR_BASE_REACHABLE_TIME_MS, /* same data as NEIGH_VAR_BASE_REACHABLE_TIME */
	62	/* Following are used by "default" only */
	63	NEIGH_VAR_GC_INTERVAL,
	64	NEIGH_VAR_GC_THRESH1,
	65	NEIGH_VAR_GC_THRESH2,
	66	NEIGH_VAR_GC_THRESH3,
	67	NEIGH_VAR_MAX
	68	};
	69
fd2c3ef7	70	struct neigh_parms {
0c5c9fb5	71	possible_net_t net;
c7fb64db	72	struct net_device *dev;
75fbfd33	73	struct list_head list;
447f2191	74	int (neigh_setup)(struct neighbour );
ecbb4169	75	void (neigh_cleanup)(struct neighbour );
1da177e4	76	struct neigh_table *tbl;
1da177e4 LT	77
	78	void *sysctl_table;
	79
	80	int dead;
6343944b	81	refcount_t refcnt;
1da177e4 LT	82	struct rcu_head rcu_head;
1da177e4 LT	83
1da177e4	84	int reachable_time;
1f9248e5	85	int data[NEIGH_VAR_DATA_MAX];
1d4c8c29	86	DECLARE_BITMAP(data_state, NEIGH_VAR_DATA_MAX);
1da177e4 LT	87	};
1da177e4 LT	88
1f9248e5 JP	89	static inline void neigh_var_set(struct neigh_parms *p, int index, int val)
1f9248e5 JP	90	{
1d4c8c29	91	set_bit(index, p->data_state);
1f9248e5 JP	92	p->data[index] = val;
	93	}
	94
	95	#define NEIGH_VAR(p, attr) ((p)->data[NEIGH_VAR_ ## attr])
89740ca7 JP	96
	97	/* In ndo_neigh_setup, NEIGH_VAR_INIT should be used.
	98	* In other cases, NEIGH_VAR_SET should be used.
	99	*/
	100	#define NEIGH_VAR_INIT(p, attr, val) (NEIGH_VAR(p, attr) = val)
1f9248e5 JP	101	#define NEIGH_VAR_SET(p, attr, val) neigh_var_set(p, NEIGH_VAR_ ## attr, val)
1f9248e5 JP	102
1d4c8c29 JP	103	static inline void neigh_parms_data_state_setall(struct neigh_parms *p)
	104	{
	105	bitmap_fill(p->data_state, NEIGH_VAR_DATA_MAX);
	106	}
	107
	108	static inline void neigh_parms_data_state_cleanall(struct neigh_parms *p)
	109	{
	110	bitmap_zero(p->data_state, NEIGH_VAR_DATA_MAX);
	111	}
	112
fd2c3ef7	113	struct neigh_statistics {
1da177e4 LT	114	unsigned long allocs; /* number of allocated neighs */
	115	unsigned long destroys; /* number of destroyed neighs */
	116	unsigned long hash_grows; /* number of hash resizes */
	117
9a6d276e	118	unsigned long res_failed; /* number of failed resolutions */
1da177e4 LT	119
	120	unsigned long lookups; /* number of lookups */
	121	unsigned long hits; /* number of hits (among lookups) */
	122
	123	unsigned long rcv_probes_mcast; /* number of received mcast ipv6 */
	124	unsigned long rcv_probes_ucast; /* number of received ucast ipv6 */
	125
	126	unsigned long periodic_gc_runs; /* number of periodic GC runs */
	127	unsigned long forced_gc_runs; /* number of forced GC runs */
9a6d276e NH	128
9a6d276e NH	129	unsigned long unres_discards; /* number of unresolved drops */
fb811395	130	unsigned long table_fulls; /* times even gc couldn't help */
1da177e4 LT	131	};
1da177e4 LT	132
4ea7334b	133	#define NEIGH_CACHE_STAT_INC(tbl, field) this_cpu_inc((tbl)->stats->field)
1da177e4	134
fd2c3ef7	135	struct neighbour {
767e97e1	136	struct neighbour __rcu *next;
1da177e4 LT	137	struct neigh_table *tbl;
1da177e4 LT	138	struct neigh_parms *parms;
1da177e4 LT	139	unsigned long confirmed;
1da177e4 LT	140	unsigned long updated;
46b13fc5	141	rwlock_t lock;
9f237430	142	refcount_t refcnt;
e37ef961	143	struct sk_buff_head arp_queue;
8b5c171b	144	unsigned int arp_queue_len_bytes;
e37ef961 ED	145	struct timer_list timer;
e37ef961 ED	146	unsigned long used;
1da177e4	147	atomic_t probes;
46b13fc5 ED	148	__u8 flags;
	149	__u8 nud_state;
	150	__u8 type;
	151	__u8 dead;
0ed8ddf4	152	seqlock_t ha_lock;
d924424a	153	unsigned char ha[ALIGN(MAX_ADDR_LEN, sizeof(unsigned long))];
f6b72b62	154	struct hh_cache hh;
8f40b161	155	int (output)(struct neighbour , struct sk_buff *);
89d69d2b	156	const struct neigh_ops *ops;
767e97e1	157	struct rcu_head rcu;
e37ef961	158	struct net_device *dev;
1da177e4	159	u8 primary_key[0];
3859a271	160	} __randomize_layout;
1da177e4	161
fd2c3ef7	162	struct neigh_ops {
1da177e4	163	int family;
8f40b161 DM	164	void (solicit)(struct neighbour , struct sk_buff *);
	165	void (error_report)(struct neighbour , struct sk_buff *);
	166	int (output)(struct neighbour , struct sk_buff *);
	167	int (connected_output)(struct neighbour , struct sk_buff *);
1da177e4 LT	168	};
1da177e4 LT	169
fd2c3ef7	170	struct pneigh_entry {
1da177e4	171	struct pneigh_entry *next;
0c5c9fb5	172	possible_net_t net;
426b5303	173	struct net_device *dev;
62dd9318	174	u8 flags;
1da177e4 LT	175	u8 key[0];
	176	};
	177
	178	/*
	179	* neighbour table manipulation
	180	*/
	181
2c2aba6c DM	182	#define NEIGH_NUM_HASH_RND 4
2c2aba6c DM	183
d6bf7817	184	struct neigh_hash_table {
767e97e1	185	struct neighbour __rcu **hash_buckets;
cd089336	186	unsigned int hash_shift;
2c2aba6c	187	__u32 hash_rnd[NEIGH_NUM_HASH_RND];
d6bf7817 ED	188	struct rcu_head rcu;
	189	};
	190
1da177e4	191
fd2c3ef7	192	struct neigh_table {
1da177e4	193	int family;
e451ae8e	194	unsigned int entry_size;
01ccdf12	195	unsigned int key_len;
bdf53c58	196	__be16 protocol;
d6bf7817 ED	197	__u32 (hash)(const void pkey,
d6bf7817 ED	198	const struct net_device *dev,
2c2aba6c	199	__u32 *hash_rnd);
60395a20	200	bool (key_eq)(const struct neighbour , const void *pkey);
1da177e4 LT	201	int (constructor)(struct neighbour );
	202	int (pconstructor)(struct pneigh_entry );
	203	void (pdestructor)(struct pneigh_entry );
	204	void (proxy_redo)(struct sk_buff skb);
	205	char *id;
	206	struct neigh_parms parms;
75fbfd33	207	struct list_head parms_list;
1da177e4 LT	208	int gc_interval;
	209	int gc_thresh1;
	210	int gc_thresh2;
	211	int gc_thresh3;
	212	unsigned long last_flush;
e4c4e448	213	struct delayed_work gc_work;
1da177e4 LT	214	struct timer_list proxy_timer;
	215	struct sk_buff_head proxy_queue;
	216	atomic_t entries;
	217	rwlock_t lock;
	218	unsigned long last_rand;
7d720c3e	219	struct neigh_statistics __percpu *stats;
d6bf7817	220	struct neigh_hash_table __rcu *nht;
1da177e4	221	struct pneigh_entry **phash_buckets;
1da177e4 LT	222	};
1da177e4 LT	223
d7480fd3 WC	224	enum {
	225	NEIGH_ARP_TABLE = 0,
	226	NEIGH_ND_TABLE = 1,
	227	NEIGH_DN_TABLE = 2,
	228	NEIGH_NR_TABLES,
b79bda3d	229	NEIGH_LINK_TABLE = NEIGH_NR_TABLES /* Pseudo table for neigh_xmit */
d7480fd3 WC	230	};
d7480fd3 WC	231
73af614a JP	232	static inline int neigh_parms_family(struct neigh_parms *p)
	233	{
	234	return p->tbl->family;
	235	}
	236
1026fec8	237	#define NEIGH_PRIV_ALIGN sizeof(long long)
daaba4fa	238	#define NEIGH_ENTRY_SIZE(size) ALIGN((size), NEIGH_PRIV_ALIGN)
1026fec8 DM	239
	240	static inline void neighbour_priv(const struct neighbour n)
	241	{
08433eff	242	return (char *)n + n->tbl->entry_size;
1026fec8 DM	243	}
1026fec8 DM	244
1da177e4 LT	245	/* flags for neigh_update() */
	246	#define NEIGH_UPDATE_F_OVERRIDE 0x00000001
	247	#define NEIGH_UPDATE_F_WEAK_OVERRIDE 0x00000002
	248	#define NEIGH_UPDATE_F_OVERRIDE_ISROUTER 0x00000004
	249	#define NEIGH_UPDATE_F_ISROUTER 0x40000000
	250	#define NEIGH_UPDATE_F_ADMIN 0x80000000
	251
60395a20 EB	252
	253	static inline bool neigh_key_eq16(const struct neighbour n, const void pkey)
	254	{
	255	return (const u16 )n->primary_key == (const u16 )pkey;
	256	}
	257
	258	static inline bool neigh_key_eq32(const struct neighbour n, const void pkey)
	259	{
	260	return (const u32 )n->primary_key == (const u32 )pkey;
	261	}
	262
	263	static inline bool neigh_key_eq128(const struct neighbour n, const void pkey)
	264	{
	265	const u32 n32 = (const u32 )n->primary_key;
	266	const u32 *p32 = pkey;
	267
	268	return ((n32[0] ^ p32[0]) \| (n32[1] ^ p32[1]) \|
	269	(n32[2] ^ p32[2]) \| (n32[3] ^ p32[3])) == 0;
	270	}
	271
	272	static inline struct neighbour *___neigh_lookup_noref(
	273	struct neigh_table *tbl,
	274	bool (key_eq)(const struct neighbour n, const void *pkey),
	275	__u32 (hash)(const void pkey,
	276	const struct net_device *dev,
	277	__u32 *hash_rnd),
	278	const void *pkey,
	279	struct net_device *dev)
	280	{
	281	struct neigh_hash_table *nht = rcu_dereference_bh(tbl->nht);
	282	struct neighbour *n;
	283	u32 hash_val;
	284
	285	hash_val = hash(pkey, dev, nht->hash_rnd) >> (32 - nht->hash_shift);
	286	for (n = rcu_dereference_bh(nht->hash_buckets[hash_val]);
	287	n != NULL;
	288	n = rcu_dereference_bh(n->next)) {
	289	if (n->dev == dev && key_eq(n, pkey))
	290	return n;
	291	}
	292
	293	return NULL;
	294	}
	295
	296	static inline struct neighbour __neigh_lookup_noref(struct neigh_table tbl,
	297	const void *pkey,
	298	struct net_device *dev)
	299	{
	300	return ___neigh_lookup_noref(tbl, tbl->key_eq, tbl->hash, pkey, dev);
	301	}
	302
d7480fd3 WC	303	void neigh_table_init(int index, struct neigh_table *tbl);
d7480fd3 WC	304	int neigh_table_clear(int index, struct neigh_table *tbl);
90972b22 JP	305	struct neighbour neigh_lookup(struct neigh_table tbl, const void *pkey,
	306	struct net_device *dev);
	307	struct neighbour neigh_lookup_nodev(struct neigh_table tbl, struct net *net,
	308	const void *pkey);
	309	struct neighbour __neigh_create(struct neigh_table tbl, const void *pkey,
	310	struct net_device *dev, bool want_ref);
a263b309	311	static inline struct neighbour neigh_create(struct neigh_table tbl,
1da177e4	312	const void *pkey,
a263b309 DM	313	struct net_device *dev)
	314	{
	315	return __neigh_create(tbl, pkey, dev, true);
	316	}
90972b22 JP	317	void neigh_destroy(struct neighbour *neigh);
90972b22 JP	318	int __neigh_event_send(struct neighbour neigh, struct sk_buff skb);
7b8f7a40 RP	319	int neigh_update(struct neighbour neigh, const u8 lladdr, u8 new, u32 flags,
7b8f7a40 RP	320	u32 nlmsg_pid);
7e980569	321	void __neigh_set_probe_once(struct neighbour *neigh);
5071034e	322	bool neigh_remove_one(struct neighbour ndel, struct neigh_table tbl);
90972b22 JP	323	void neigh_changeaddr(struct neigh_table tbl, struct net_device dev);
	324	int neigh_ifdown(struct neigh_table tbl, struct net_device dev);
	325	int neigh_resolve_output(struct neighbour neigh, struct sk_buff skb);
	326	int neigh_connected_output(struct neighbour neigh, struct sk_buff skb);
90972b22 JP	327	int neigh_direct_output(struct neighbour neigh, struct sk_buff skb);
90972b22 JP	328	struct neighbour neigh_event_ns(struct neigh_table tbl,
1da177e4 LT	329	u8 lladdr, void saddr,
	330	struct net_device *dev);
	331
90972b22 JP	332	struct neigh_parms neigh_parms_alloc(struct net_device dev,
	333	struct neigh_table *tbl);
	334	void neigh_parms_release(struct neigh_table tbl, struct neigh_parms parms);
57da52c1 YH	335
57da52c1 YH	336	static inline
90972b22	337	struct net neigh_parms_net(const struct neigh_parms parms)
57da52c1	338	{
e42ea986	339	return read_pnet(&parms->net);
57da52c1 YH	340	}
57da52c1 YH	341
90972b22	342	unsigned long neigh_rand_reach_time(unsigned long base);
1da177e4	343
90972b22 JP	344	void pneigh_enqueue(struct neigh_table tbl, struct neigh_parms p,
	345	struct sk_buff *skb);
	346	struct pneigh_entry pneigh_lookup(struct neigh_table tbl, struct net *net,
	347	const void key, struct net_device dev,
	348	int creat);
	349	struct pneigh_entry __pneigh_lookup(struct neigh_table tbl, struct net *net,
	350	const void key, struct net_device dev);
	351	int pneigh_delete(struct neigh_table tbl, struct net net, const void *key,
	352	struct net_device *dev);
1da177e4	353
90972b22	354	static inline struct net pneigh_net(const struct pneigh_entry pneigh)
57da52c1	355	{
e42ea986	356	return read_pnet(&pneigh->net);
57da52c1 YH	357	}
57da52c1 YH	358
90972b22 JP	359	void neigh_app_ns(struct neighbour *n);
	360	void neigh_for_each(struct neigh_table *tbl,
	361	void (cb)(struct neighbour , void ), void cookie);
	362	void __neigh_for_each_release(struct neigh_table *tbl,
	363	int (cb)(struct neighbour ));
4fd3d7d9	364	int neigh_xmit(int fam, struct net_device , const void , struct sk_buff *);
90972b22 JP	365	void pneigh_for_each(struct neigh_table *tbl,
90972b22 JP	366	void (cb)(struct pneigh_entry ));
1da177e4 LT	367
1da177e4 LT	368	struct neigh_seq_state {
42508461	369	struct seq_net_private p;
1da177e4	370	struct neigh_table *tbl;
d6bf7817	371	struct neigh_hash_table *nht;
1da177e4 LT	372	void (neigh_sub_iter)(struct neigh_seq_state *state,
	373	struct neighbour n, loff_t pos);
	374	unsigned int bucket;
	375	unsigned int flags;
	376	#define NEIGH_SEQ_NEIGH_ONLY 0x00000001
	377	#define NEIGH_SEQ_IS_PNEIGH 0x00000002
	378	#define NEIGH_SEQ_SKIP_NOARP 0x00000004
	379	};
90972b22 JP	380	void neigh_seq_start(struct seq_file , loff_t , struct neigh_table ,
	381	unsigned int);
	382	void neigh_seq_next(struct seq_file , void , loff_t );
	383	void neigh_seq_stop(struct seq_file , void );
	384
cb5b09c1 JP	385	int neigh_proc_dointvec(struct ctl_table *ctl, int write,
	386	void __user buffer, size_t lenp, loff_t *ppos);
	387	int neigh_proc_dointvec_jiffies(struct ctl_table *ctl, int write,
	388	void __user *buffer,
	389	size_t lenp, loff_t ppos);
	390	int neigh_proc_dointvec_ms_jiffies(struct ctl_table *ctl, int write,
	391	void __user *buffer,
	392	size_t lenp, loff_t ppos);
	393
90972b22	394	int neigh_sysctl_register(struct net_device dev, struct neigh_parms p,
73af614a	395	proc_handler *proc_handler);
90972b22	396	void neigh_sysctl_unregister(struct neigh_parms *p);
1da177e4 LT	397
	398	static inline void __neigh_parms_put(struct neigh_parms *parms)
	399	{
6343944b	400	refcount_dec(&parms->refcnt);
1da177e4 LT	401	}
1da177e4 LT	402
1da177e4 LT	403	static inline struct neigh_parms neigh_parms_clone(struct neigh_parms parms)
1da177e4 LT	404	{
6343944b	405	refcount_inc(&parms->refcnt);
1da177e4 LT	406	return parms;
	407	}
	408
	409	/*
	410	* Neighbour references
	411	*/
	412
	413	static inline void neigh_release(struct neighbour *neigh)
	414	{
9f237430	415	if (refcount_dec_and_test(&neigh->refcnt))
1da177e4 LT	416	neigh_destroy(neigh);
	417	}
	418
	419	static inline struct neighbour * neigh_clone(struct neighbour *neigh)
	420	{
	421	if (neigh)
9f237430	422	refcount_inc(&neigh->refcnt);
1da177e4 LT	423	return neigh;
	424	}
	425
9f237430	426	#define neigh_hold(n) refcount_inc(&(n)->refcnt)
1da177e4	427
1da177e4 LT	428	static inline int neigh_event_send(struct neighbour neigh, struct sk_buff skb)
1da177e4 LT	429	{
ef22b7b6	430	unsigned long now = jiffies;
0ed8ddf4	431
8967c079 ED	432	if (READ_ONCE(neigh->used) != now)
8967c079 ED	433	WRITE_ONCE(neigh->used, now);
1da177e4 LT	434	if (!(neigh->nud_state&(NUD_CONNECTED\|NUD_DELAY\|NUD_PROBE)))
	435	return __neigh_event_send(neigh, skb);
	436	return 0;
	437	}
	438
34666d46	439	#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
e179e632 BDS	440	static inline int neigh_hh_bridge(struct hh_cache hh, struct sk_buff skb)
e179e632 BDS	441	{
95c96174	442	unsigned int seq, hh_alen;
e179e632 BDS	443
	444	do {
	445	seq = read_seqbegin(&hh->hh_lock);
	446	hh_alen = HH_DATA_ALIGN(ETH_HLEN);
	447	memcpy(skb->data - hh_alen, hh->hh_data, ETH_ALEN + hh_alen - ETH_HLEN);
	448	} while (read_seqretry(&hh->hh_lock, seq));
	449	return 0;
	450	}
	451	#endif
	452
425f09ab	453	static inline int neigh_hh_output(const struct hh_cache hh, struct sk_buff skb)
3644f0ce	454	{
c13b5259	455	unsigned int hh_alen = 0;
95c96174	456	unsigned int seq;
5b3dc2f3	457	unsigned int hh_len;
3644f0ce SH	458
3644f0ce SH	459	do {
3644f0ce SH	460	seq = read_seqbegin(&hh->hh_lock);
3644f0ce SH	461	hh_len = hh->hh_len;
425f09ab	462	if (likely(hh_len <= HH_DATA_MOD)) {
c13b5259 SB	463	hh_alen = HH_DATA_MOD;
	464
	465	/* skb_push() would proceed silently if we have room for
	466	* the unaligned size but not for the aligned size:
	467	* check headroom explicitly.
	468	*/
	469	if (likely(skb_headroom(skb) >= HH_DATA_MOD)) {
	470	/* this is inlined by gcc */
	471	memcpy(skb->data - HH_DATA_MOD, hh->hh_data,
	472	HH_DATA_MOD);
	473	}
425f09ab	474	} else {
c13b5259	475	hh_alen = HH_DATA_ALIGN(hh_len);
425f09ab	476
c13b5259 SB	477	if (likely(skb_headroom(skb) >= hh_alen)) {
	478	memcpy(skb->data - hh_alen, hh->hh_data,
	479	hh_alen);
	480	}
425f09ab	481	}
3644f0ce SH	482	} while (read_seqretry(&hh->hh_lock, seq));
3644f0ce SH	483
c13b5259 SB	484	if (WARN_ON_ONCE(skb_headroom(skb) < hh_alen)) {
	485	kfree_skb(skb);
	486	return NET_XMIT_DROP;
	487	}
	488
	489	__skb_push(skb, hh_len);
b23b5455	490	return dev_queue_xmit(skb);
3644f0ce SH	491	}
3644f0ce SH	492
c16ec185 JA	493	static inline int neigh_output(struct neighbour n, struct sk_buff skb)
	494	{
	495	const struct hh_cache *hh = &n->hh;
	496
	497	if ((n->nud_state & NUD_CONNECTED) && hh->hh_len)
	498	return neigh_hh_output(hh, skb);
	499	else
	500	return n->output(n, skb);
	501	}
	502
1da177e4 LT	503	static inline struct neighbour *
	504	__neigh_lookup(struct neigh_table tbl, const void pkey, struct net_device *dev, int creat)
	505	{
	506	struct neighbour *n = neigh_lookup(tbl, pkey, dev);
	507
	508	if (n \|\| !creat)
	509	return n;
	510
	511	n = neigh_create(tbl, pkey, dev);
	512	return IS_ERR(n) ? NULL : n;
	513	}
	514
	515	static inline struct neighbour *
	516	__neigh_lookup_errno(struct neigh_table tbl, const void pkey,
	517	struct net_device *dev)
	518	{
	519	struct neighbour *n = neigh_lookup(tbl, pkey, dev);
	520
	521	if (n)
	522	return n;
	523
	524	return neigh_create(tbl, pkey, dev);
	525	}
	526
a61bbcf2 PM	527	struct neighbour_cb {
	528	unsigned long sched_next;
	529	unsigned int flags;
	530	};
	531
	532	#define LOCALLY_ENQUEUED 0x1
	533
	534	#define NEIGH_CB(skb) ((struct neighbour_cb *)(skb)->cb)
1da177e4	535
0ed8ddf4 ED	536	static inline void neigh_ha_snapshot(char dst, const struct neighbour n,
	537	const struct net_device *dev)
	538	{
	539	unsigned int seq;
	540
	541	do {
	542	seq = read_seqbegin(&n->ha_lock);
	543	memcpy(dst, n->ha, dev->addr_len);
	544	} while (read_seqretry(&n->ha_lock, seq));
	545	}
4fd3d7d9 EB	546
4fd3d7d9 EB	547
1da177e4	548	#endif