#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_DNSSL = 31, /* RFC6106 */
__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 <linux/if_arp.h>
#include <linux/netdevice.h>
#include <linux/hash.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 rd_msg {
struct icmp6hdr icmph;
struct in6_addr target;
struct in6_addr dest;
__u8 opt[0];
};

struct nd_opt_hdr {
__u8 nd_opt_type;
__u8 nd_opt_len;
} __packed;

/* ND options */
struct ndisc_options {
struct nd_opt_hdr *nd_opt_array[__ND_OPT_ARRAY_MAX];
#ifdef CONFIG_IPV6_ROUTE_INFO
struct nd_opt_hdr *nd_opts_ri;
struct nd_opt_hdr *nd_opts_ri_end;
#endif
struct nd_opt_hdr *nd_useropts;
struct nd_opt_hdr *nd_useropts_end;
};

#define nd_opts_src_lladdr nd_opt_array[ND_OPT_SOURCE_LL_ADDR]
#define nd_opts_tgt_lladdr nd_opt_array[ND_OPT_TARGET_LL_ADDR]
#define nd_opts_pi nd_opt_array[ND_OPT_PREFIX_INFO]
#define nd_opts_pi_end nd_opt_array[__ND_OPT_PREFIX_INFO_END]
#define nd_opts_rh nd_opt_array[ND_OPT_REDIRECT_HDR]
#define nd_opts_mtu nd_opt_array[ND_OPT_MTU]

#define NDISC_OPT_SPACE(len) (((len)+2+7)&~7)

struct ndisc_options *ndisc_parse_options(u8 *opt, int opt_len,
struct ndisc_options *ndopts);

/*
* Return the padding between the option length and the start of the
* link addr. Currently only IP-over-InfiniBand needs this, although
* if RFC 3831 IPv6-over-Fibre Channel is ever implemented it may
* also need a pad of 2.
*/
static inline int ndisc_addr_option_pad(unsigned short type)
{
switch (type) {
case ARPHRD_INFINIBAND: return 2;
default: return 0;
}
}

static inline int ndisc_opt_addr_space(struct net_device *dev)
{
return NDISC_OPT_SPACE(dev->addr_len +
ndisc_addr_option_pad(dev->type));
}

static inline u8 *ndisc_opt_addr_data(struct nd_opt_hdr *p,
struct net_device *dev)
{
u8 *lladdr = (u8 *)(p + 1);
int lladdrlen = p->nd_opt_len << 3;
int prepad = ndisc_addr_option_pad(dev->type);
if (lladdrlen != ndisc_opt_addr_space(dev))
return NULL;
return lladdr + prepad;
}

static inline u32 ndisc_hashfn(const void *pkey, const struct net_device *dev, __u32 *hash_rnd)
{
const u32 *p32 = pkey;

return (((p32[0] ^ hash32_ptr(dev)) * 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_noref(struct net_device *dev, const void *pkey)
{
struct neigh_hash_table *nht;
const u32 *p32 = pkey;
struct neighbour *n;
u32 hash_val;

nht = rcu_dereference_bh(nd_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)
return n;
}

return NULL;
}

static inline struct neighbour *__ipv6_neigh_lookup(struct net_device *dev, const void *pkey)
{
struct neighbour *n;

rcu_read_lock_bh();
n = __ipv6_neigh_lookup_noref(dev, pkey);
if (n && !atomic_inc_not_zero(&n->refcnt))
n = NULL;
rcu_read_unlock_bh();

return n;
}

int ndisc_init(void);
int ndisc_late_init(void);

void ndisc_late_cleanup(void);
void ndisc_cleanup(void);

int ndisc_rcv(struct sk_buff *skb);

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);

void ndisc_send_rs(struct net_device *dev,
const struct in6_addr *saddr, const struct in6_addr *daddr);
void ndisc_send_na(struct net_device *dev, struct neighbour *neigh,
const struct in6_addr *daddr,
const struct in6_addr *solicited_addr,
bool router, bool solicited, bool override, bool inc_opt);

void ndisc_send_redirect(struct sk_buff *skb, const struct in6_addr *target);

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


/*
* IGMP
*/
int igmp6_init(void);

void igmp6_cleanup(void);

int igmp6_event_query(struct sk_buff *skb);

int igmp6_event_report(struct sk_buff *skb);


#ifdef CONFIG_SYSCTL
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(struct ctl_table *ctl,
void __user *oldval, size_t __user *oldlenp,
void __user *newval, size_t newlen);
#endif

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

#endif