#ifndef _NDISC_H
#define _NDISC_H


/*
 *	Neighbor Cache Entry States (7.3.2.)
 */

/*
 *	The lsb is set for states that have a timer associated
 */

#define NUD_NONE	0x00
#define NUD_INCOMPLETE	0x11
#define NUD_REACHABLE	0x20
#define NUD_STALE	0x30
#define NUD_DELAY	0x41
#define NUD_PROBE	0x51
#define NUD_FAILED	0x60	/* neighbour discovery failed	*/

#define NUD_IN_TIMER	0x01

#define NDISC_QUEUE_LEN	3

#define NCF_NOARP		0x0100	/* no ARP needed on this device */
#define NCF_SUBNET		0x0200  /* NC entry for subnet		*/
#define NCF_INVALID		0x0400
#define NCF_DELAY_EXPIRED	0x0800	/* time to move to PROBE	*/
#define NCF_ROUTER		0x1000	/* neighbour is a router	*/
#define NCF_HHVALID		0x2000	/* Hardware header is valid	*/

/*
 *	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

/*
 *	ndisc options
 */

#define ND_OPT_SOURCE_LL_ADDR		1
#define ND_OPT_TARGET_LL_ADDR		2
#define ND_OPT_PREFIX_INFO		3
#define ND_OPT_REDIRECT_HDR		4
#define ND_OPT_MTU			5

#define MAX_RTR_SOLICITATION_DELAY	HZ

#define RECHABLE_TIME			(30*HZ)
#define RETRANS_TIMER			HZ

#define MIN_RANDOM_FACTOR		(1/2)
#define MAX_RANDOM_FACTOR		(3/2)

#define REACH_RANDOM_INTERVAL		(60*60*HZ)	/* 1 hour */

#ifdef __KERNEL__

#include <linux/skbuff.h>
#include <linux/netdevice.h>
#include <linux/icmpv6.h>
#include <net/neighbour.h>
#include <asm/atomic.h>

/*
 *	neighbour cache entry
 *	used by neighbour discovery module
 */

struct nd_neigh {
	struct neighbour	neigh;
	struct in6_addr		ndn_addr;	/* next hop addr */

	__u8			ndn_plen,	/* prefix len	 */
				ndn_type,	/* {unicast, multicast} */
				ndn_nud_state,
				ndn_probes;
	
	unsigned long		ndn_expires;	/* timer expires at	*/

#define ndn_refcnt		neigh.refcnt
#define ndn_tstamp		neigh.lastused
#define ndn_dev			neigh.dev
#define ndn_flags		neigh.flags
#define ndn_ha			neigh.ha
};

struct nd_msg {
        struct icmp6hdr	icmph;
        struct in6_addr	target;
        struct {
                __u8	opt_type;
                __u8	opt_len;
                __u8	link_addr[MAX_ADDR_LEN];
        } opt;
};

struct ra_msg {
        struct icmp6hdr		icmph;
	__u32			reachable_time;
	__u32			retrans_timer;
};

struct ndisc_statistics {
	__u32	allocs;			/* allocated entries		*/
	__u32	free_delayed;		/* zombie entries		*/
	__u32	snt_probes_ucast;	/* ns probes sent (ucast)	*/
	__u32	snt_probes_mcast;	/* ns probes sent (mcast)	*/
	__u32	rcv_probes_ucast;	/* ns probes rcv  (ucast)	*/
	__u32	rcv_probes_mcast;	/* ns probes rcv  (mcast)	*/
	__u32	rcv_upper_conf;		/* confirmations from upper layers */
	__u32	res_failed;		/* address resolution failures	*/
};

extern struct neighbour *	ndisc_find_neigh(struct device *dev, 
						 struct in6_addr *addr);

extern void			ndisc_validate(struct neighbour *neigh);

extern void			ndisc_init(struct net_proto_family *ops);
extern struct neighbour*	ndisc_get_neigh(struct device *dev,
						struct in6_addr *addr);
extern void			ndisc_cleanup(void);

extern int			ndisc_rcv(struct sk_buff *skb,
					  struct device *dev,
					  struct in6_addr *saddr,
					  struct in6_addr *daddr,
					  struct ipv6_options *opt,
					  unsigned short len);

extern void			ndisc_event_send(struct neighbour *neigh,
						 struct sk_buff *skb);

extern void			ndisc_send_ns(struct device *dev,
					      struct neighbour *neigh,
					      struct in6_addr *solicit,
					      struct in6_addr *daddr,
					      struct in6_addr *saddr);

extern void			ndisc_send_rs(struct device *dev,
					      struct in6_addr *saddr,
					      struct in6_addr *daddr);

extern int			ndisc_eth_resolv(unsigned char *,
						struct sk_buff *);

extern void			ndisc_forwarding_on(void);
extern void			ndisc_forwarding_off(void);

extern void			ndisc_send_redirect(struct sk_buff *skb,
						    struct neighbour *neigh,
						    struct in6_addr *target);

struct rt6_info *		dflt_rt_lookup(void);

extern unsigned long	nd_rand_seed;
extern unsigned long	ipv6_random(void);

/*
 *	IGMP
 */
extern void			igmp6_init(struct net_proto_family *ops);

extern int			igmp6_event_query(struct sk_buff *skb,
						  struct icmp6hdr *hdr,
						  int len);

extern int			igmp6_event_report(struct sk_buff *skb,
						   struct icmp6hdr *hdr,
						   int len);

#endif /* __KERNEL__ */


#endif