/*-
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * 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.
 *
 *      $KAME: nd6.h,v 1.76 2001/12/18 02:10:31 itojun Exp $
 */

#ifndef _NETINET6_ND6_H_
#define _NETINET6_ND6_H_

/* see net/route.h, or net/if_inarp.h */
#ifndef RTF_ANNOUNCE
#define RTF_ANNOUNCE    RTF_PROTO2
#endif

#include <sys/queue.h>
#include <sys/callout.h>

struct llentry;

#define ND6_LLINFO_NOSTATE      -2
/*
 * We don't need the WAITDELETE state any more, but we keep the definition
 * in a comment line instead of removing it. This is necessary to avoid
 * unintentionally reusing the value for another purpose, which might
 * affect backward compatibility with old applications.
 * (20000711 jinmei@kame.net)
 */
/* #define ND6_LLINFO_WAITDELETE        -1 */
#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

#define ND6_IS_LLINFO_PROBREACH(n) ((n)->ln_state > ND6_LLINFO_INCOMPLETE)
#define ND6_LLINFO_PERMANENT(n) (((n)->la_expire == 0) && ((n)->ln_state > ND6_LLINFO_INCOMPLETE))

#define ND6_IFF_PERFORMNUD      0x1
#define ND6_IFF_ACCEPT_RTADV    0x2
#define ND6_IFF_PREFER_SOURCE   0x4 /* Not used in FreeBSD. */
#define ND6_IFF_IFDISABLED      0x8 /* IPv6 operation is disabled due to
                                     * DAD failure.  (XXX: not ND-specific)
                                     */
#define ND6_IFF_DONT_SET_IFROUTE        0x10
#define ND6_IFF_AUTO_LINKLOCAL  0x20
#define ND6_IFF_NO_RADR         0x40
#define ND6_IFF_NO_PREFER_IFACE 0x80 /* XXX: not related to ND. */
#define ND6_IFF_NO_DAD          0x100
#define ND6_IFF_STABLEADDR      0x800
#ifdef EXPERIMENTAL
/* XXX: not related to ND. */
#define ND6_IFF_IPV6_ONLY       0x200 /* draft-ietf-6man-ipv6only-flag */
#define ND6_IFF_IPV6_ONLY_MANUAL        0x400
#define ND6_IFF_IPV6_ONLY_MASK  (ND6_IFF_IPV6_ONLY|ND6_IFF_IPV6_ONLY_MANUAL)
#endif

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

/* Sysctls, shared with user space. */
struct  in6_defrouter {
        struct  sockaddr_in6 rtaddr;
        u_char  flags;
        u_short rtlifetime;
        u_long  expire;
        u_short if_index;
};

struct in6_prefix {
        struct  sockaddr_in6 prefix;
        struct prf_ra raflags;
        u_char  prefixlen;
        u_char  origin;
        u_int32_t vltime;
        u_int32_t pltime;
        time_t expire;
        u_int32_t flags;
        int refcnt;
        u_short if_index;
        u_short advrtrs; /* number of advertisement routers */
        /* struct sockaddr_in6 advrtr[] */
};

struct in6_ndireq {
        char ifname[IFNAMSIZ];
        struct nd_ifinfo {
                uint32_t linkmtu;       /* LinkMTU */
                uint32_t maxmtu;        /* Upper bound of LinkMTU */
                uint32_t basereachable; /* BaseReachableTime */
                uint32_t reachable;     /* Reachable Time */
                uint32_t retrans;       /* Retrans Timer */
                uint32_t flags;         /* Flags */
                int recalctm;           /* BaseReacable re-calculation timer */
                uint8_t chlim;          /* CurHopLimit */
                /*
                 * The below members are not used.  They came from KAME and
                 * are hanging around to preserve ABI compatibility of the
                 * SIOCGIFINFO_IN6 ioctl.
                 * The original comment documented the random* members as a
                 * privacy extension for addrconf.
                 */
                uint8_t initialized;    /* compat: always 1 */
                uint8_t randomseed0[8]; /* upper 64 bits of MD5 digest */
                uint8_t randomseed1[8]; /* lower 64 bits (the EUI64 IFID?) */
                uint8_t randomid[8];    /* current random ID */
        } ndi;
};

struct  in6_ndifreq {
        char ifname[IFNAMSIZ];
        u_long ifindex;
};

/* Prefix status */
#define NDPRF_ONLINK            0x1
#define NDPRF_DETACHED          0x2

/* ND6 NA output flags */
#define ND6_NA_OPT_LLA          0x01
#define ND6_NA_CARP_MASTER      0x02

/* ND6 queue flags */
#define ND6_QUEUE_FLAG_NEWGUA   0x01    /* new global unicast address event */
#define ND6_QUEUE_FLAG_LLADDR   0x02    /* link-layer address change event */
#define ND6_QUEUE_FLAG_ANYCAST  0x04    /* delay NA for anycast address */
#define ND6_QUEUE_FLAG_PROXY    0x08    /* delay NA for proxy address */

/* GRAND specific flags */
#define ND6_QUEUE_GRAND_MASK    (ND6_QUEUE_FLAG_NEWGUA|ND6_QUEUE_FLAG_LLADDR)

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

#define ND6_INFINITE_LIFETIME           0xffffffff

#ifdef _KERNEL
/* node constants */
#define MAX_REACHABLE_TIME              3600000 /* msec */
#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 DEF_TEMP_VALID_LIFETIME         172800  /* 2 days */
#define DEF_TEMP_PREFERRED_LIFETIME     86400   /* 1 day */
#define TEMPADDR_REGEN_ADVANCE          5       /* sec */
#define TEMP_MAX_DESYNC_FACTOR_BASE     300     /* 5 min */
#define ND_COMPUTE_RTIME(x) \
                (((MIN_RANDOM_FACTOR * (x >> 10)) + (arc4random() & \
                ((MAX_RANDOM_FACTOR - MIN_RANDOM_FACTOR) * (x >> 10)))) /1000)
#define MAX_NEIGHBOR_ADVERTISEMENT      3       /* RFC4891 Section 10 */

struct nd_defrouter {
        TAILQ_ENTRY(nd_defrouter) dr_entry;
        struct in6_addr rtaddr;
        u_char  raflags;        /* flags on RA message */
        u_short rtlifetime;
        u_long  expire;
        struct ifnet *ifp;
        int     installed;      /* is installed into kernel routing table */
        u_int   refcnt;
};

struct nd_prefixctl {
        struct ifnet *ndpr_ifp;

        /* prefix */
        struct sockaddr_in6 ndpr_prefix;
        u_char  ndpr_plen;

        u_int32_t ndpr_vltime;  /* advertised valid lifetime */
        u_int32_t ndpr_pltime;  /* advertised preferred lifetime */

        struct prf_ra ndpr_flags;
};

LIST_HEAD(nd_prhead, nd_prefix);
struct nd_prefix {
        struct ifnet *ndpr_ifp;
        LIST_ENTRY(nd_prefix) ndpr_entry;
        struct sockaddr_in6 ndpr_prefix;        /* prefix */
        struct in6_addr ndpr_mask; /* netmask derived from the prefix */

        u_int32_t ndpr_vltime;  /* advertised valid lifetime */
        u_int32_t ndpr_pltime;  /* advertised preferred lifetime */

        time_t ndpr_expire;     /* expiration time of the prefix */
        time_t ndpr_preferred;  /* preferred time of the prefix */
        time_t ndpr_lastupdate; /* reception time of last advertisement */

        struct prf_ra ndpr_flags;
        u_int32_t ndpr_stateflags; /* actual state flags */
        /* list of routers that advertise the prefix: */
        LIST_HEAD(pr_rtrhead, nd_pfxrouter) ndpr_advrtrs;
        u_char  ndpr_plen;
        int     ndpr_addrcnt;   /* count of derived addresses */
        volatile u_int ndpr_refcnt;
};

#define ndpr_raf                ndpr_flags
#define ndpr_raf_onlink         ndpr_flags.onlink
#define ndpr_raf_auto           ndpr_flags.autonomous
#define ndpr_raf_router         ndpr_flags.router

struct nd_pfxrouter {
        LIST_ENTRY(nd_pfxrouter) pfr_entry;
        struct nd_defrouter *router;
};

/* nd6.c */
VNET_DECLARE(int, nd6_mmaxtries);
VNET_DECLARE(struct nd_prhead, nd_prefix);
VNET_DECLARE(int, nd6_debug);
#define V_nd6_mmaxtries                 VNET(nd6_mmaxtries)
#define V_nd_prefix                     VNET(nd_prefix)
#define V_nd6_debug                     VNET(nd6_debug)

/* Lock for the prefix and default router lists. */
VNET_DECLARE(struct rwlock, nd6_lock);
VNET_DECLARE(uint64_t, nd6_list_genid);
#define V_nd6_lock                      VNET(nd6_lock)
#define V_nd6_list_genid                VNET(nd6_list_genid)

#define ND6_RLOCK()                     rw_rlock(&V_nd6_lock)
#define ND6_RUNLOCK()                   rw_runlock(&V_nd6_lock)
#define ND6_WLOCK()                     rw_wlock(&V_nd6_lock)
#define ND6_WUNLOCK()                   rw_wunlock(&V_nd6_lock)
#define ND6_TRY_UPGRADE()               rw_try_upgrade(&V_nd6_lock)
#define ND6_WLOCK_ASSERT()              rw_assert(&V_nd6_lock, RA_WLOCKED)
#define ND6_RLOCK_ASSERT()              rw_assert(&V_nd6_lock, RA_RLOCKED)
#define ND6_LOCK_ASSERT()               rw_assert(&V_nd6_lock, RA_LOCKED)
#define ND6_UNLOCK_ASSERT()             rw_assert(&V_nd6_lock, RA_UNLOCKED)

/* Mutex for prefix onlink/offlink transitions. */
VNET_DECLARE(struct mtx, nd6_onlink_mtx);
#define V_nd6_onlink_mtx                VNET(nd6_onlink_mtx)

#define ND6_ONLINK_LOCK()               mtx_lock(&V_nd6_onlink_mtx)
#define ND6_ONLINK_TRYLOCK()            mtx_trylock(&V_nd6_onlink_mtx)
#define ND6_ONLINK_UNLOCK()             mtx_unlock(&V_nd6_onlink_mtx)
#define ND6_ONLINK_LOCK_ASSERT()        mtx_assert(&V_nd6_onlink_mtx, MA_OWNED)
#define ND6_ONLINK_UNLOCK_ASSERT()      mtx_assert(&V_nd6_onlink_mtx, MA_NOTOWNED)

#define nd6log(x)       do { if (V_nd6_debug) log x; } while (/*CONSTCOND*/ 0)

/* nd6_rtr.c */
VNET_DECLARE(int, nd6_defifindex);
VNET_DECLARE(int, ip6_desync_factor);   /* seconds */
VNET_DECLARE(uint32_t, ip6_temp_max_desync_factor); /* seconds */
VNET_DECLARE(u_int32_t, ip6_temp_preferred_lifetime); /* seconds */
VNET_DECLARE(u_int32_t, ip6_temp_valid_lifetime); /* seconds */
VNET_DECLARE(int, ip6_temp_regen_advance); /* seconds */
#define V_nd6_defifindex                VNET(nd6_defifindex)
#define V_ip6_desync_factor             VNET(ip6_desync_factor)
#define V_ip6_temp_max_desync_factor    VNET(ip6_temp_max_desync_factor)
#define V_ip6_temp_preferred_lifetime   VNET(ip6_temp_preferred_lifetime)
#define V_ip6_temp_valid_lifetime       VNET(ip6_temp_valid_lifetime)
#define V_ip6_temp_regen_advance        VNET(ip6_temp_regen_advance)

union nd_opts {
        struct nd_opt_hdr *nd_opt_array[16];    /* max = ND_OPT_NONCE */
        struct {
                struct nd_opt_hdr *zero;
                struct nd_opt_hdr *src_lladdr;
                struct nd_opt_hdr *tgt_lladdr;
                struct nd_opt_prefix_info *pi_beg; /* multiple opts, start */
                struct nd_opt_rd_hdr *rh;
                struct nd_opt_mtu *mtu;
                struct nd_opt_hdr *__res6;
                struct nd_opt_hdr *__res7;
                struct nd_opt_hdr *__res8;
                struct nd_opt_hdr *__res9;
                struct nd_opt_hdr *__res10;
                struct nd_opt_hdr *__res11;
                struct nd_opt_hdr *__res12;
                struct nd_opt_hdr *__res13;
                struct nd_opt_nonce *nonce;
                struct nd_opt_hdr *__res15;
                struct nd_opt_hdr *search;      /* multiple opts */
                struct nd_opt_hdr *last;        /* multiple opts */
                int done;
                struct nd_opt_prefix_info *pi_end;/* multiple opts, end */
        } nd_opt_each;
};
#define nd_opts_src_lladdr      nd_opt_each.src_lladdr
#define nd_opts_tgt_lladdr      nd_opt_each.tgt_lladdr
#define nd_opts_pi              nd_opt_each.pi_beg
#define nd_opts_pi_end          nd_opt_each.pi_end
#define nd_opts_rh              nd_opt_each.rh
#define nd_opts_mtu             nd_opt_each.mtu
#define nd_opts_nonce           nd_opt_each.nonce
#define nd_opts_search          nd_opt_each.search
#define nd_opts_last            nd_opt_each.last
#define nd_opts_done            nd_opt_each.done

/* XXX: need nd6_var.h?? */
/* nd6.c */
void nd6_init(void);
#ifdef VIMAGE
void nd6_destroy(void);
#endif
void nd6_ifattach(struct ifnet *);
void nd6_ifdetach(struct ifnet *);
int nd6_is_addr_neighbor(const struct sockaddr_in6 *, struct ifnet *);
void nd6_option_init(void *, int, union nd_opts *);
struct nd_opt_hdr *nd6_option(union nd_opts *);
int nd6_options(union nd_opts *);
struct llentry *nd6_lookup(const struct in6_addr *, int, struct ifnet *);
void nd6_setmtu(struct ifnet *);
void nd6_llinfo_setstate(struct llentry *lle, int newstate);
void nd6_timer(void *);
void nd6_purge(struct ifnet *);
int nd6_resolve_addr(struct ifnet *ifp, int flags, const struct sockaddr *dst,
    char *desten, uint32_t *pflags);
int nd6_resolve(struct ifnet *, int, struct mbuf *,
    const struct sockaddr *, u_char *, uint32_t *, struct llentry **);
int nd6_ioctl(u_long, caddr_t, struct ifnet *);
void nd6_cache_lladdr(struct ifnet *, struct in6_addr *,
        char *, int, int, int);
bool nd6_try_set_entry_addr(struct ifnet *ifp, struct llentry *lle, char *lladdr);
struct mbuf *nd6_grab_holdchain(struct llentry *);
int nd6_flush_holdchain(struct ifnet *, struct llentry *, struct mbuf *);
void nd6_flush_children_holdchain(struct ifnet *, struct llentry *);
int nd6_add_ifa_lle(struct in6_ifaddr *);
void nd6_rem_ifa_lle(struct in6_ifaddr *, int);
int nd6_output_ifp(struct ifnet *, struct ifnet *, struct mbuf *,
    struct sockaddr_in6 *, struct route *);

struct rib_head;
struct rib_cmd_info;
void nd6_subscription_cb(struct rib_head *rnh, struct rib_cmd_info *rc,
    void *arg);

/* nd6_nbr.c */
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 *, uint8_t *);
caddr_t nd6_ifptomac(struct ifnet *);
void nd6_dad_init(void);
void nd6_dad_start(struct ifaddr *, int);
void nd6_dad_stop(struct ifaddr *);
void nd6_grand_start(struct ifaddr *, uint32_t);
void nd6_queue_stop(struct ifaddr *);

/* nd6_rtr.c */
void nd6_rs_input(struct mbuf *, int, int);
void nd6_ra_input(struct mbuf *, int, int);
void nd6_ifnet_link_event(void *, struct ifnet *, int);
struct nd_defrouter *defrouter_lookup(const struct in6_addr *, struct ifnet *);
struct nd_defrouter *defrouter_lookup_locked(const struct in6_addr *,
    struct ifnet *);
void defrouter_reset(void);
void defrouter_select_fib(int fibnum);
void defrouter_rele(struct nd_defrouter *);
bool defrouter_remove(struct in6_addr *, struct ifnet *);
bool nd6_defrouter_list_empty(void);
void nd6_defrouter_flush_all(void);
void nd6_defrouter_purge(struct ifnet *);
void nd6_defrouter_timer(void);
void nd6_defrouter_init(void);
int nd6_prelist_add(struct nd_prefixctl *, struct nd_defrouter *,
    struct nd_prefix **);
void nd6_prefix_unlink(struct nd_prefix *, struct nd_prhead *);
void nd6_prefix_del(struct nd_prefix *);
void nd6_prefix_ref(struct nd_prefix *);
void nd6_prefix_rele(struct nd_prefix *);
int nd6_prefix_offlink(struct nd_prefix *);
void pfxlist_onlink_check(void);
struct nd_prefix *nd6_prefix_lookup(struct nd_prefixctl *);
void rt6_flush(struct in6_addr *, struct ifnet *);
int nd6_setdefaultiface(int);
int in6_tmpifadd(const struct in6_ifaddr *, int, int);

#endif /* _KERNEL */

#endif /* _NETINET6_ND6_H_ */