/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
#ifndef __LINUX_NEIGHBOUR_H
#define __LINUX_NEIGHBOUR_H

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

struct ndmsg {
        __u8            ndm_family;
        __u8            ndm_pad1;
        __u16           ndm_pad2;
        __s32           ndm_ifindex;
        __u16           ndm_state;
        __u8            ndm_flags;
        __u8            ndm_type;
};

enum {
        NDA_UNSPEC,
        NDA_DST,
        NDA_LLADDR,
        NDA_CACHEINFO,
        NDA_PROBES,
        NDA_VLAN,
        NDA_PORT,
        NDA_VNI,
        NDA_IFINDEX,
        NDA_MASTER,
        NDA_LINK_NETNSID,
        NDA_SRC_VNI,
        NDA_PROTOCOL,  /* Originator of entry */
        NDA_NH_ID,
        NDA_FDB_EXT_ATTRS,
        NDA_FLAGS_EXT,
        NDA_NDM_STATE_MASK,
        NDA_NDM_FLAGS_MASK,
        __NDA_MAX
};

#define NDA_MAX (__NDA_MAX - 1)

/*
 *      Neighbor Cache Entry Flags
 */

#define NTF_USE         (1 << 0)
#define NTF_SELF        (1 << 1)
#define NTF_MASTER      (1 << 2)
#define NTF_PROXY       (1 << 3)        /* == ATF_PUBL */
#define NTF_EXT_LEARNED (1 << 4)
#define NTF_OFFLOADED   (1 << 5)
#define NTF_STICKY      (1 << 6)
#define NTF_ROUTER      (1 << 7)
/* Extended flags under NDA_FLAGS_EXT: */
#define NTF_EXT_MANAGED (1 << 0)

/*
 *      Neighbor Cache Entry States.
 */

#define NUD_INCOMPLETE  0x01
#define NUD_REACHABLE   0x02
#define NUD_STALE       0x04
#define NUD_DELAY       0x08
#define NUD_PROBE       0x10
#define NUD_FAILED      0x20

/* Dummy states */
#define NUD_NOARP       0x40
#define NUD_PERMANENT   0x80
#define NUD_NONE        0x00

/* NUD_NOARP & NUD_PERMANENT are pseudostates, they never change and make no
 * address resolution or NUD.
 *
 * NUD_PERMANENT also cannot be deleted by garbage collectors. This holds true
 * for dynamic entries with NTF_EXT_LEARNED flag as well. However, upon carrier
 * down event, NUD_PERMANENT entries are not flushed whereas NTF_EXT_LEARNED
 * flagged entries explicitly are (which is also consistent with the routing
 * subsystem).
 *
 * When NTF_EXT_LEARNED is set for a bridge fdb entry the different cache entry
 * states don't make sense and thus are ignored. Such entries don't age and
 * can roam.
 *
 * NTF_EXT_MANAGED flagged neigbor entries are managed by the kernel on behalf
 * of a user space control plane, and automatically refreshed so that (if
 * possible) they remain in NUD_REACHABLE state.
 */

struct nda_cacheinfo {
        __u32           ndm_confirmed;
        __u32           ndm_used;
        __u32           ndm_updated;
        __u32           ndm_refcnt;
};

/*****************************************************************
 *              Neighbour tables specific messages.
 *
 * To retrieve the neighbour tables send RTM_GETNEIGHTBL with the
 * NLM_F_DUMP flag set. Every neighbour table configuration is
 * spread over multiple messages to avoid running into message
 * size limits on systems with many interfaces. The first message
 * in the sequence transports all not device specific data such as
 * statistics, configuration, and the default parameter set.
 * This message is followed by 0..n messages carrying device
 * specific parameter sets.
 * Although the ordering should be sufficient, NDTA_NAME can be
 * used to identify sequences. The initial message can be identified
 * by checking for NDTA_CONFIG. The device specific messages do
 * not contain this TLV but have NDTPA_IFINDEX set to the
 * corresponding interface index.
 *
 * To change neighbour table attributes, send RTM_SETNEIGHTBL
 * with NDTA_NAME set. Changeable attribute include NDTA_THRESH[1-3],
 * NDTA_GC_INTERVAL, and all TLVs in NDTA_PARMS unless marked
 * otherwise. Device specific parameter sets can be changed by
 * setting NDTPA_IFINDEX to the interface index of the corresponding
 * device.
 ****/

struct ndt_stats {
        __u64           ndts_allocs;
        __u64           ndts_destroys;
        __u64           ndts_hash_grows;
        __u64           ndts_res_failed;
        __u64           ndts_lookups;
        __u64           ndts_hits;
        __u64           ndts_rcv_probes_mcast;
        __u64           ndts_rcv_probes_ucast;
        __u64           ndts_periodic_gc_runs;
        __u64           ndts_forced_gc_runs;
        __u64           ndts_table_fulls;
};

enum {
        NDTPA_UNSPEC,
        NDTPA_IFINDEX,                  /* u32, unchangeable */
        NDTPA_REFCNT,                   /* u32, read-only */
        NDTPA_REACHABLE_TIME,           /* u64, read-only, msecs */
        NDTPA_BASE_REACHABLE_TIME,      /* u64, msecs */
        NDTPA_RETRANS_TIME,             /* u64, msecs */
        NDTPA_GC_STALETIME,             /* u64, msecs */
        NDTPA_DELAY_PROBE_TIME,         /* u64, msecs */
        NDTPA_QUEUE_LEN,                /* u32 */
        NDTPA_APP_PROBES,               /* u32 */
        NDTPA_UCAST_PROBES,             /* u32 */
        NDTPA_MCAST_PROBES,             /* u32 */
        NDTPA_ANYCAST_DELAY,            /* u64, msecs */
        NDTPA_PROXY_DELAY,              /* u64, msecs */
        NDTPA_PROXY_QLEN,               /* u32 */
        NDTPA_LOCKTIME,                 /* u64, msecs */
        NDTPA_QUEUE_LENBYTES,           /* u32 */
        NDTPA_MCAST_REPROBES,           /* u32 */
        NDTPA_PAD,
        __NDTPA_MAX
};
#define NDTPA_MAX (__NDTPA_MAX - 1)

struct ndtmsg {
        __u8            ndtm_family;
        __u8            ndtm_pad1;
        __u16           ndtm_pad2;
};

struct ndt_config {
        __u16           ndtc_key_len;
        __u16           ndtc_entry_size;
        __u32           ndtc_entries;
        __u32           ndtc_last_flush;        /* delta to now in msecs */
        __u32           ndtc_last_rand;         /* delta to now in msecs */
        __u32           ndtc_hash_rnd;
        __u32           ndtc_hash_mask;
        __u32           ndtc_hash_chain_gc;
        __u32           ndtc_proxy_qlen;
};

enum {
        NDTA_UNSPEC,
        NDTA_NAME,                      /* char *, unchangeable */
        NDTA_THRESH1,                   /* u32 */
        NDTA_THRESH2,                   /* u32 */
        NDTA_THRESH3,                   /* u32 */
        NDTA_CONFIG,                    /* struct ndt_config, read-only */
        NDTA_PARMS,                     /* nested TLV NDTPA_* */
        NDTA_STATS,                     /* struct ndt_stats, read-only */
        NDTA_GC_INTERVAL,               /* u64, msecs */
        NDTA_PAD,
        __NDTA_MAX
};
#define NDTA_MAX (__NDTA_MAX - 1)

 /* FDB activity notification bits used in NFEA_ACTIVITY_NOTIFY:
  * - FDB_NOTIFY_BIT - notify on activity/expire for any entry
  * - FDB_NOTIFY_INACTIVE_BIT - mark as inactive to avoid multiple notifications
  */
enum {
        FDB_NOTIFY_BIT          = (1 << 0),
        FDB_NOTIFY_INACTIVE_BIT = (1 << 1)
};

/* embedded into NDA_FDB_EXT_ATTRS:
 * [NDA_FDB_EXT_ATTRS] = {
 *     [NFEA_ACTIVITY_NOTIFY]
 *     ...
 * }
 */
enum {
        NFEA_UNSPEC,
        NFEA_ACTIVITY_NOTIFY,
        NFEA_DONT_REFRESH,
        __NFEA_MAX
};
#define NFEA_MAX (__NFEA_MAX - 1)

#endif