/*      $OpenBSD: nd6.h,v 1.106 2026/03/23 13:12:39 jsg Exp $   */
/*      $KAME: nd6.h,v 1.95 2002/06/08 11:31:06 itojun Exp $    */

/*
 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the project nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#ifndef _NETINET6_ND6_H_
#define _NETINET6_ND6_H_

#define ND6_LLINFO_PURGE        -3
#define ND6_LLINFO_NOSTATE      -2
#define ND6_LLINFO_INCOMPLETE   0
#define ND6_LLINFO_REACHABLE    1
#define ND6_LLINFO_STALE        2
#define ND6_LLINFO_DELAY        3
#define ND6_LLINFO_PROBE        4

/*
 * Locks used to protect struct members in this file:
 *      I       immutable after creation
 *      K       kernel lock
 *      m       nd6 mutex, needed when net lock is shared
 *      N       net lock
 */

struct nd_ifinfo {
        u_int32_t reachable;            /* [N] Reachable Time */
        int recalctm;                   /* [N] BaseReachable recalc timer */
};

struct in6_nbrinfo {
        char ifname[IFNAMSIZ];  /* if name, e.g. "en0" */
        struct in6_addr addr;   /* IPv6 address of the neighbor */
        time_t  expire;         /* lifetime for NDP state transition */
        long    asked;          /* number of queries already sent for addr */
        int     isrouter;       /* if it acts as a router */
        int     state;          /* reachability state */
};

struct  in6_ndireq {
        char ifname[IFNAMSIZ];
        struct nd_ifinfo ndi;
};

/* protocol constants */
#define MAX_RTR_SOLICITATION_DELAY      1       /*1sec*/
#define RTR_SOLICITATION_INTERVAL       4       /*4sec*/
#define MAX_RTR_SOLICITATIONS           3

#define ND6_INFINITE_LIFETIME           0xffffffff

#ifdef _KERNEL

#include <sys/queue.h>

struct llinfo_nd6 {
        TAILQ_ENTRY(llinfo_nd6)  ln_list;       /* [m] global nd6_list */
        struct  rtentry         *ln_rt;         /* [I] backpointer to rtentry */
        /* keep fields above in sync with struct llinfo_nd6_iterator */
        struct  refcnt           ln_refcnt;     /* entry referenced by list */
        struct  mbuf_queue ln_mq;       /* hold packets until resolved */
        struct  in6_addr ln_saddr6;     /* source of prompting packet */
        long    ln_asked;       /* number of queries already sent for addr */
        short   ln_state;       /* reachability state */
        short   ln_router;      /* 2^0: ND6 router bit */
};
#define LN_HOLD_QUEUE 10
#define LN_HOLD_TOTAL 100

struct llinfo_nd6_iterator {
        TAILQ_ENTRY(llinfo_nd6)  ln_list;       /* [m] global nd6_list */
        struct  rtentry         *ln_rt;         /* [I] always NULL */
        /* keep fields above in sync with struct llinfo_nd6 */
};

extern unsigned int ln_hold_total;

#define ND6_LLINFO_PERMANENT(n) ((n)->ln_rt->rt_expire == 0)

/* node constants */
#define REACHABLE_TIME                  30000   /* msec */
#define RETRANS_TIMER                   1000    /* msec */
#define MIN_RANDOM_FACTOR               512     /* 1024 * 0.5 */
#define MAX_RANDOM_FACTOR               1536    /* 1024 * 1.5 */
#define ND_COMPUTE_RTIME(x) \
                (((MIN_RANDOM_FACTOR * (x >> 10)) + (arc4random() & \
                ((MAX_RANDOM_FACTOR - MIN_RANDOM_FACTOR) * (x >> 10)))) /1000)

extern int nd6_delay;
extern int nd6_umaxtries;
extern int nd6_mmaxtries;
extern const int nd6_gctimer;

struct nd_opts {
        struct nd_opt_hdr *nd_opts_src_lladdr;
        struct nd_opt_hdr *nd_opts_tgt_lladdr;
};

void nd6_init(void);
void nd6_ifattach(struct ifnet *);
void nd6_ifdetach(struct ifnet *);
int nd6_is_addr_neighbor(const struct sockaddr_in6 *, struct ifnet *);
int nd6_options(void *, int, struct nd_opts *);
struct  rtentry *nd6_lookup(const struct in6_addr *, int, struct ifnet *,
    u_int);
void nd6_llinfo_settimer(const struct llinfo_nd6 *, unsigned int);
void nd6_purge(struct ifnet *);
void nd6_rtrequest(struct ifnet *, int, struct rtentry *);
int nd6_ioctl(u_long, caddr_t, struct ifnet *);
void nd6_cache_lladdr(struct ifnet *, const struct in6_addr *, char *,
    int, int, int, int);
int nd6_resolve(struct ifnet *, struct rtentry *, struct mbuf *,
         struct sockaddr *, u_char *);
int nd6_need_cache(struct ifnet *);

void nd6_na_input(struct mbuf *, int, int);
void nd6_na_output(struct ifnet *, const struct in6_addr *,
        const struct in6_addr *, u_long, int, struct sockaddr *);
void nd6_ns_input(struct mbuf *, int, int);
void nd6_ns_output(struct ifnet *, const struct in6_addr *,
        const struct in6_addr *, const struct in6_addr *, int);
caddr_t nd6_ifptomac(struct ifnet *);
void nd6_dad_start(struct ifaddr *);
void nd6_dad_stop(struct ifaddr *);

void nd6_rtr_cache(struct mbuf *, int, int, int);

int rt6_flush(struct in6_addr *, struct ifnet *);

void nd6_expire_timer_update(struct in6_ifaddr *);
#endif /* _KERNEL */

#endif /* _NETINET6_ND6_H_ */