include/net/neighbour.h

   1 #ifndef _NET_NEIGHBOUR_H
   2 #define _NET_NEIGHBOUR_H
   3
   4 /*
   5  *      Generic neighbour manipulation
   6  *
   7  *      Authors:
   8  *      Pedro Roque             <roque@di.fc.ul.pt>
   9  *      Alexey Kuznetsov        <kuznet@ms2.inr.ac.ru>
  10  */
  11
  12 /* The following flags & states are exported to user space,
  13    so that they should be moved to include/linux/ directory.
  14  */
  15
  16 /*
  17  *      Neighbor Cache Entry Flags
  18  */
  19
  20 #define NTF_PROXY       0x08    /* == ATF_PUBL */
  21 #define NTF_ROUTER      0x80
  22
  23 /*
  24  *      Neighbor Cache Entry States.
  25  */
  26
  27 #define NUD_INCOMPLETE  0x01
  28 #define NUD_REACHABLE   0x02
  29 #define NUD_STALE       0x04
  30 #define NUD_DELAY       0x08
  31 #define NUD_PROBE       0x10
  32 #define NUD_FAILED      0x20
  33
  34 /* Dummy states */
  35 #define NUD_NOARP       0x40
  36 #define NUD_PERMANENT   0x80
  37 #define NUD_NONE        0x00
  38
  39 /* NUD_NOARP & NUD_PERMANENT are pseudostates, they never change
  40    and make no address resolution or NUD.
  41    NUD_PERMANENT is also cannot be deleted by garbage collectors.
  42  */
  43
  44 #ifdef __KERNEL__
  45
  46 #include <asm/atomic.h>
  47 #include <linux/skbuff.h>
  48
  49 #include <linux/err.h>
  50 #include <linux/sysctl.h>
  51
  52 #define NUD_IN_TIMER    (NUD_INCOMPLETE|NUD_DELAY|NUD_PROBE)
  53 #define NUD_VALID       (NUD_PERMANENT|NUD_NOARP|NUD_REACHABLE|NUD_PROBE|NUD_STALE|NUD_DELAY)
  54 #define NUD_CONNECTED   (NUD_PERMANENT|NUD_NOARP|NUD_REACHABLE)
  55
  56 struct neigh_parms
  57 {
  58         struct neigh_parms *next;
  59         int     (*neigh_setup)(struct neighbour *);
  60         struct neigh_table *tbl;
  61         int     entries;
  62         void    *priv;
  63
  64         void    *sysctl_table;
  65
  66         int     base_reachable_time;
  67         int     retrans_time;
  68         int     gc_staletime;
  69         int     reachable_time;
  70         int     delay_probe_time;
  71
  72         int     queue_len;
  73         int     ucast_probes;
  74         int     app_probes;
  75         int     mcast_probes;
  76         int     anycast_delay;
  77         int     proxy_delay;
  78         int     proxy_qlen;
  79         int     locktime;
  80 };
  81
  82 struct neigh_statistics
  83 {
  84         unsigned long allocs;
  85         unsigned long res_failed;
  86         unsigned long rcv_probes_mcast;
  87         unsigned long rcv_probes_ucast;
  88 };
  89
  90 struct neighbour
  91 {
  92         struct neighbour        *next;
  93         struct neigh_table      *tbl;
  94         struct neigh_parms      *parms;
  95         struct net_device               *dev;
  96         unsigned long           used;
  97         unsigned long           confirmed;
  98         unsigned long           updated;
  99         __u8                    flags;
 100         __u8                    nud_state;
 101         __u8                    type;
 102         __u8                    dead;
 103         atomic_t                probes;
 104         rwlock_t                lock;
 105         unsigned char           ha[(MAX_ADDR_LEN+sizeof(unsigned long)-1)&~(sizeof(unsigned long)-1)];
 106         struct hh_cache         *hh;
 107         atomic_t                refcnt;
 108         int                     (*output)(struct sk_buff *skb);
 109         struct sk_buff_head     arp_queue;
 110         struct timer_list       timer;
 111         struct neigh_ops        *ops;
 112         u8                      primary_key[0];
 113 };
 114
 115 struct neigh_ops
 116 {
 117         int                     family;
 118         void                    (*destructor)(struct neighbour *);
 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 {
 129         struct pneigh_entry     *next;
 130         struct net_device               *dev;
 131         u8                      key[0];
 132 };
 133
 134 #define NEIGH_HASHMASK          0x1F
 135 #define PNEIGH_HASHMASK         0xF
 136
 137 /*
 138  *      neighbour table manipulation
 139  */
 140
 141
 142 struct neigh_table
 143 {
 144         struct neigh_table      *next;
 145         int                     family;
 146         int                     entry_size;
 147         int                     key_len;
 148         __u32                   (*hash)(const void *pkey, const struct net_device *);
 149         int                     (*constructor)(struct neighbour *);
 150         int                     (*pconstructor)(struct pneigh_entry *);
 151         void                    (*pdestructor)(struct pneigh_entry *);
 152         void                    (*proxy_redo)(struct sk_buff *skb);
 153         char                    *id;
 154         struct neigh_parms      parms;
 155         /* HACK. gc_* shoul follow parms without a gap! */
 156         int                     gc_interval;
 157         int                     gc_thresh1;
 158         int                     gc_thresh2;
 159         int                     gc_thresh3;
 160         unsigned long           last_flush;
 161         struct timer_list       gc_timer;
 162         struct timer_list       proxy_timer;
 163         struct sk_buff_head     proxy_queue;
 164         int                     entries;
 165         rwlock_t                lock;
 166         unsigned long           last_rand;
 167         struct neigh_parms      *parms_list;
 168         kmem_cache_t            *kmem_cachep;
 169         struct neigh_statistics stats;
 170         struct neighbour        *hash_buckets[NEIGH_HASHMASK+1];
 171         struct pneigh_entry     *phash_buckets[PNEIGH_HASHMASK+1];
 172 };
 173
 174 extern void                     neigh_table_init(struct neigh_table *tbl);
 175 extern int                      neigh_table_clear(struct neigh_table *tbl);
 176 extern struct neighbour *       neigh_lookup(struct neigh_table *tbl,
 177                                              const void *pkey,
 178                                              struct net_device *dev);
 179 extern struct neighbour *       neigh_create(struct neigh_table *tbl,
 180                                              const void *pkey,
 181                                              struct net_device *dev);
 182 extern void                     neigh_destroy(struct neighbour *neigh);
 183 extern int                      __neigh_event_send(struct neighbour *neigh, struct sk_buff *skb);
 184 extern int                      neigh_update(struct neighbour *neigh, const u8 *lladdr, u8 new, int override, int arp);
 185 extern void                     neigh_changeaddr(struct neigh_table *tbl, struct net_device *dev);
 186 extern int                      neigh_ifdown(struct neigh_table *tbl, struct net_device *dev);
 187 extern int                      neigh_resolve_output(struct sk_buff *skb);
 188 extern int                      neigh_connected_output(struct sk_buff *skb);
 189 extern int                      neigh_compat_output(struct sk_buff *skb);
 190 extern struct neighbour         *neigh_event_ns(struct neigh_table *tbl,
 191                                                 u8 *lladdr, void *saddr,
 192                                                 struct net_device *dev);
 193
 194 extern struct neigh_parms       *neigh_parms_alloc(struct net_device *dev, struct neigh_table *tbl);
 195 extern void                     neigh_parms_release(struct neigh_table *tbl, struct neigh_parms *parms);
 196 extern unsigned long            neigh_rand_reach_time(unsigned long base);
 197
 198 extern void                     pneigh_enqueue(struct neigh_table *tbl, struct neigh_parms *p,
 199                                                struct sk_buff *skb);
 200 extern struct pneigh_entry      *pneigh_lookup(struct neigh_table *tbl, const void *key, struct net_device *dev, int creat);
 201 extern int                      pneigh_delete(struct neigh_table *tbl, const void *key, struct net_device *dev);
 202
 203 struct netlink_callback;
 204 struct nlmsghdr;
 205 extern int neigh_dump_info(struct sk_buff *skb, struct netlink_callback *cb);
 206 extern int neigh_add(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg);
 207 extern int neigh_delete(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg);
 208 extern void neigh_app_ns(struct neighbour *n);
 209
 210 extern int                      neigh_sysctl_register(struct net_device *dev,
 211                                                       struct neigh_parms *p,
 212                                                       int p_id, int pdev_id,
 213                                                       char *p_name,
 214                                                       proc_handler *proc_handler);
 215 extern void                     neigh_sysctl_unregister(struct neigh_parms *p);
 216
 217 /*
 218  *      Neighbour references
 219  */
 220
 221 static inline void neigh_release(struct neighbour *neigh)
 222 {
 223         if (atomic_dec_and_test(&neigh->refcnt))
 224                 neigh_destroy(neigh);
 225 }
 226
 227 static inline struct neighbour * neigh_clone(struct neighbour *neigh)
 228 {
 229         if (neigh)
 230                 atomic_inc(&neigh->refcnt);
 231         return neigh;
 232 }
 233
 234 #define neigh_hold(n)   atomic_inc(&(n)->refcnt)
 235
 236 static inline void neigh_confirm(struct neighbour *neigh)
 237 {
 238         if (neigh)
 239                 neigh->confirmed = jiffies;
 240 }
 241
 242 static inline int neigh_is_connected(struct neighbour *neigh)
 243 {
 244         return neigh->nud_state&NUD_CONNECTED;
 245 }
 246
 247 static inline int neigh_is_valid(struct neighbour *neigh)
 248 {
 249         return neigh->nud_state&NUD_VALID;
 250 }
 251
 252 static inline int neigh_event_send(struct neighbour *neigh, struct sk_buff *skb)
 253 {
 254         neigh->used = jiffies;
 255         if (!(neigh->nud_state&(NUD_CONNECTED|NUD_DELAY|NUD_PROBE)))
 256                 return __neigh_event_send(neigh, skb);
 257         return 0;
 258 }
 259
 260 static inline struct neighbour *
 261 __neigh_lookup(struct neigh_table *tbl, const void *pkey, struct net_device *dev, int creat)
 262 {
 263         struct neighbour *n = neigh_lookup(tbl, pkey, dev);
 264
 265         if (n || !creat)
 266                 return n;
 267
 268         n = neigh_create(tbl, pkey, dev);
 269         return IS_ERR(n) ? NULL : n;
 270 }
 271
 272 static inline struct neighbour *
 273 __neigh_lookup_errno(struct neigh_table *tbl, const void *pkey,
 274   struct net_device *dev)
 275 {
 276         struct neighbour *n = neigh_lookup(tbl, pkey, dev);
 277
 278         if (n)
 279                 return n;
 280
 281         return neigh_create(tbl, pkey, dev);
 282 }
 283
 284 #define LOCALLY_ENQUEUED -2
 285
 286 #endif
 287 #endif
 288
 289