#ifndef _NDISC_H
  #define _NDISC_H
  
  /*
   *	ICMP codes for neighbour discovery messages
   */
  
  #define NDISC_ROUTER_SOLICITATION	133
  #define NDISC_ROUTER_ADVERTISEMENT	134
  #define NDISC_NEIGHBOUR_SOLICITATION	135
  #define NDISC_NEIGHBOUR_ADVERTISEMENT	136
  #define NDISC_REDIRECT			137
  
  /*

   * Router type: cross-layer information from link-layer to
   * IPv6 layer reported by certain link types (e.g., RFC4214).
   */
  #define NDISC_NODETYPE_UNSPEC		0	/* unspecified (default) */
  #define NDISC_NODETYPE_HOST		1	/* host or unauthorized router */
  #define NDISC_NODETYPE_NODEFAULT	2	/* non-default router */
  #define NDISC_NODETYPE_DEFAULT		3	/* default router */
  
  /*

   *	ndisc options
   */
  
  enum {
  	__ND_OPT_PREFIX_INFO_END = 0,
  	ND_OPT_SOURCE_LL_ADDR = 1,	/* RFC2461 */
  	ND_OPT_TARGET_LL_ADDR = 2,	/* RFC2461 */
  	ND_OPT_PREFIX_INFO = 3,		/* RFC2461 */
  	ND_OPT_REDIRECT_HDR = 4,	/* RFC2461 */
  	ND_OPT_MTU = 5,			/* RFC2461 */

  	__ND_OPT_ARRAY_MAX,
  	ND_OPT_ROUTE_INFO = 24,		/* RFC4191 */

  	ND_OPT_RDNSS = 25,		/* RFC5006 */

  	__ND_OPT_MAX
  };
  
  #define MAX_RTR_SOLICITATION_DELAY	HZ
  
  #define ND_REACHABLE_TIME		(30*HZ)
  #define ND_RETRANS_TIMER		HZ

  #include <linux/compiler.h>

  #include <linux/icmpv6.h>

  #include <linux/in6.h>
  #include <linux/types.h>

  #include <net/neighbour.h>

  
  struct ctl_table;

  struct inet6_dev;
  struct net_device;
  struct net_proto_family;
  struct sk_buff;

  
  extern struct neigh_table nd_tbl;
  
  struct nd_msg {
          struct icmp6hdr	icmph;
          struct in6_addr	target;
  	__u8		opt[0];
  };
  
  struct rs_msg {
  	struct icmp6hdr	icmph;
  	__u8		opt[0];
  };
  
  struct ra_msg {
          struct icmp6hdr		icmph;

  	__be32			reachable_time;
  	__be32			retrans_timer;

  };
  
  struct nd_opt_hdr {
  	__u8		nd_opt_type;
  	__u8		nd_opt_len;

  } __packed;

  static inline u32 ndisc_hashfn(const void *pkey, const struct net_device *dev, __u32 *hash_rnd)
  {
  	const u32 *p32 = pkey;
  
  	return (((p32[0] ^ dev->ifindex) * hash_rnd[0]) +
  		(p32[1] * hash_rnd[1]) +
  		(p32[2] * hash_rnd[2]) +
  		(p32[3] * hash_rnd[3]));
  }

  static inline struct neighbour *__ipv6_neigh_lookup(struct neigh_table *tbl, struct net_device *dev, const void *pkey)
  {
  	struct neigh_hash_table *nht;
  	const u32 *p32 = pkey;
  	struct neighbour *n;
  	u32 hash_val;
  
  	rcu_read_lock_bh();
  	nht = rcu_dereference_bh(tbl->nht);
  	hash_val = ndisc_hashfn(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)) {
  		u32 *n32 = (u32 *) n->primary_key;
  		if (n->dev == dev &&
  		    ((n32[0] ^ p32[0]) | (n32[1] ^ p32[1]) |
  		     (n32[2] ^ p32[2]) | (n32[3] ^ p32[3])) == 0) {
  			if (!atomic_inc_not_zero(&n->refcnt))
  				n = NULL;
  			break;
  		}
  	}
  	rcu_read_unlock_bh();
  
  	return n;
  }

  extern int			ndisc_init(void);

  
  extern void			ndisc_cleanup(void);
  
  extern int			ndisc_rcv(struct sk_buff *skb);
  
  extern void			ndisc_send_ns(struct net_device *dev,
  					      struct neighbour *neigh,

  					      const struct in6_addr *solicit,
  					      const struct in6_addr *daddr,
  					      const struct in6_addr *saddr);

  
  extern void			ndisc_send_rs(struct net_device *dev,

  					      const struct in6_addr *saddr,
  					      const struct in6_addr *daddr);

  extern void			ndisc_send_redirect(struct sk_buff *skb,
  						    struct neighbour *neigh,

  						    const struct in6_addr *target);

  extern int			ndisc_mc_map(const struct in6_addr *addr, char *buf,
  					     struct net_device *dev, int dir);

  extern struct sk_buff		*ndisc_build_skb(struct net_device *dev,
  						 const struct in6_addr *daddr,
  						 const struct in6_addr *saddr,
  						 struct icmp6hdr *icmp6h,
  						 const struct in6_addr *target,
  						 int llinfo);
  
  extern void			ndisc_send_skb(struct sk_buff *skb,
  					       struct net_device *dev,
  					       struct neighbour *neigh,
  					       const struct in6_addr *daddr,
  					       const struct in6_addr *saddr,
  					       struct icmp6hdr *icmp6h);

  
  /*
   *	IGMP
   */

  extern int			igmp6_init(void);

  
  extern void			igmp6_cleanup(void);
  
  extern int			igmp6_event_query(struct sk_buff *skb);
  
  extern int			igmp6_event_report(struct sk_buff *skb);

  
  #ifdef CONFIG_SYSCTL

  extern int 			ndisc_ifinfo_sysctl_change(struct ctl_table *ctl,

  							   int write,

  							   void __user *buffer,
  							   size_t *lenp,
  							   loff_t *ppos);

  int ndisc_ifinfo_sysctl_strategy(ctl_table *ctl,
  				 void __user *oldval, size_t __user *oldlenp,

  				 void __user *newval, size_t newlen);

  #endif
  
  extern void 			inet6_ifinfo_notify(int event,
  						    struct inet6_dev *idev);

  #endif