mesh.h

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/*
 * Copyright (c) 2008, 2009 open80211s Ltd.
 * Authors:    Luis Carlos Cobo <[email protected]>
 *             Javier Cardona <[email protected]>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#ifndef IEEE80211S_H
#define IEEE80211S_H

#include <linux/types.h>
#include <linux/jhash.h>
#include "ieee80211_i.h"


/* Data structures */

enum mesh_config_capab_flags {
    MESHCONF_CAPAB_ACCEPT_PLINKS = BIT(0),
    MESHCONF_CAPAB_FORWARDING = BIT(3),
    MESHCONF_CAPAB_TBTT_ADJUSTING = BIT(5),
};

enum mesh_path_flags {
    MESH_PATH_ACTIVE =  BIT(0),
    MESH_PATH_RESOLVING =   BIT(1),
    MESH_PATH_SN_VALID =    BIT(2),
    MESH_PATH_FIXED =   BIT(3),
    MESH_PATH_RESOLVED =    BIT(4),
    MESH_PATH_REQ_QUEUED =  BIT(5),
};

enum mesh_deferred_task_flags {
    MESH_WORK_HOUSEKEEPING,
    MESH_WORK_GROW_MPATH_TABLE,
    MESH_WORK_GROW_MPP_TABLE,
    MESH_WORK_ROOT,
    MESH_WORK_DRIFT_ADJUST,
};

struct mesh_path {
    u8 dst[ETH_ALEN];
    u8 mpp[ETH_ALEN];   /* used for MPP or MAP */
    struct ieee80211_sub_if_data *sdata;
    struct sta_info __rcu *next_hop;
    struct timer_list timer;
    struct sk_buff_head frame_queue;
    struct rcu_head rcu;
    u32 sn;
    u32 metric;
    u8 hop_count;
    unsigned long exp_time;
    u32 discovery_timeout;
    u8 discovery_retries;
    enum mesh_path_flags flags;
    spinlock_t state_lock;
    u8 rann_snd_addr[ETH_ALEN];
    u32 rann_metric;
    unsigned long last_preq_to_root;
    bool is_root;
    bool is_gate;
};

struct mesh_table {
    /* Number of buckets will be 2^N */
    struct hlist_head *hash_buckets;
    spinlock_t *hashwlock;      /* One per bucket, for add/del */
    unsigned int hash_mask;     /* (2^size_order) - 1 */
    __u32 hash_rnd;         /* Used for hash generation */
    atomic_t entries;       /* Up to MAX_MESH_NEIGHBOURS */
    void (*free_node) (struct hlist_node *p, bool free_leafs);
    int (*copy_node) (struct hlist_node *p, struct mesh_table *newtbl);
    int size_order;
    int mean_chain_len;
    struct hlist_head *known_gates;
    spinlock_t gates_lock;

    struct rcu_head rcu_head;
};

/* Recent multicast cache */
/* RMC_BUCKETS must be a power of 2, maximum 256 */
#define RMC_BUCKETS     256
#define RMC_QUEUE_MAX_LEN   4
#define RMC_TIMEOUT     (3 * HZ)

struct rmc_entry {
    struct list_head list;
    u32 seqnum;
    unsigned long exp_time;
    u8 sa[ETH_ALEN];
};

struct mesh_rmc {
    struct rmc_entry bucket[RMC_BUCKETS];
    u32 idx_mask;
};

#define IEEE80211_MESH_PEER_INACTIVITY_LIMIT (1800 * HZ)
#define IEEE80211_MESH_HOUSEKEEPING_INTERVAL (60 * HZ)

#define MESH_DEFAULT_BEACON_INTERVAL        1000    /* in 1024 us units */

#define MESH_PATH_EXPIRE (600 * HZ)

/* Default maximum number of plinks per interface */
#define MESH_MAX_PLINKS     256

/* Maximum number of paths per interface */
#define MESH_MAX_MPATHS     1024

/* Number of frames buffered per destination for unresolved destinations */
#define MESH_FRAME_QUEUE_LEN    10

/* Public interfaces */
/* Various */
int ieee80211_fill_mesh_addresses(struct ieee80211_hdr *hdr, __le16 *fc,
                  const u8 *da, const u8 *sa);
int ieee80211_new_mesh_header(struct ieee80211s_hdr *meshhdr,
        struct ieee80211_sub_if_data *sdata, char *addr4or5,
        char *addr6);
int mesh_rmc_check(u8 *addr, struct ieee80211s_hdr *mesh_hdr,
        struct ieee80211_sub_if_data *sdata);
bool mesh_matches_local(struct ieee80211_sub_if_data *sdata,
            struct ieee802_11_elems *ie);
void mesh_ids_set_default(struct ieee80211_if_mesh *mesh);
void mesh_mgmt_ies_add(struct sk_buff *skb,
        struct ieee80211_sub_if_data *sdata);
int mesh_add_meshconf_ie(struct sk_buff *skb,
             struct ieee80211_sub_if_data *sdata);
int mesh_add_meshid_ie(struct sk_buff *skb,
               struct ieee80211_sub_if_data *sdata);
int mesh_add_rsn_ie(struct sk_buff *skb,
            struct ieee80211_sub_if_data *sdata);
int mesh_add_vendor_ies(struct sk_buff *skb,
            struct ieee80211_sub_if_data *sdata);
int mesh_add_ds_params_ie(struct sk_buff *skb,
              struct ieee80211_sub_if_data *sdata);
int mesh_add_ht_cap_ie(struct sk_buff *skb,
               struct ieee80211_sub_if_data *sdata);
int mesh_add_ht_oper_ie(struct sk_buff *skb,
            struct ieee80211_sub_if_data *sdata);
void mesh_rmc_free(struct ieee80211_sub_if_data *sdata);
int mesh_rmc_init(struct ieee80211_sub_if_data *sdata);
void ieee80211s_init(void);
void ieee80211s_update_metric(struct ieee80211_local *local,
        struct sta_info *sta, struct sk_buff *skb);
void ieee80211s_stop(void);
void ieee80211_mesh_init_sdata(struct ieee80211_sub_if_data *sdata);
void ieee80211_start_mesh(struct ieee80211_sub_if_data *sdata);
void ieee80211_stop_mesh(struct ieee80211_sub_if_data *sdata);
void ieee80211_mesh_root_setup(struct ieee80211_if_mesh *ifmsh);
struct ieee80211_mesh_sync_ops *ieee80211_mesh_sync_ops_get(u8 method);

/* Mesh paths */
int mesh_nexthop_lookup(struct sk_buff *skb,
        struct ieee80211_sub_if_data *sdata);
int mesh_nexthop_resolve(struct sk_buff *skb,
             struct ieee80211_sub_if_data *sdata);
void mesh_path_start_discovery(struct ieee80211_sub_if_data *sdata);
struct mesh_path *mesh_path_lookup(u8 *dst,
        struct ieee80211_sub_if_data *sdata);
struct mesh_path *mpp_path_lookup(u8 *dst,
                  struct ieee80211_sub_if_data *sdata);
int mpp_path_add(u8 *dst, u8 *mpp, struct ieee80211_sub_if_data *sdata);
struct mesh_path *mesh_path_lookup_by_idx(int idx,
        struct ieee80211_sub_if_data *sdata);
void mesh_path_fix_nexthop(struct mesh_path *mpath, struct sta_info *next_hop);
void mesh_path_expire(struct ieee80211_sub_if_data *sdata);
void mesh_rx_path_sel_frame(struct ieee80211_sub_if_data *sdata,
        struct ieee80211_mgmt *mgmt, size_t len);
int mesh_path_add(u8 *dst, struct ieee80211_sub_if_data *sdata);

int mesh_path_add_gate(struct mesh_path *mpath);
int mesh_path_send_to_gates(struct mesh_path *mpath);
int mesh_gate_num(struct ieee80211_sub_if_data *sdata);
/* Mesh plinks */
void mesh_neighbour_update(struct ieee80211_sub_if_data *sdata,
               u8 *hw_addr,
               struct ieee802_11_elems *ie);
bool mesh_peer_accepts_plinks(struct ieee802_11_elems *ie);
u32 mesh_accept_plinks_update(struct ieee80211_sub_if_data *sdata);
void mesh_plink_broken(struct sta_info *sta);
void mesh_plink_deactivate(struct sta_info *sta);
int mesh_plink_open(struct sta_info *sta);
void mesh_plink_block(struct sta_info *sta);
void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata,
             struct ieee80211_mgmt *mgmt, size_t len,
             struct ieee80211_rx_status *rx_status);

/* Private interfaces */
/* Mesh tables */
void mesh_mpath_table_grow(void);
void mesh_mpp_table_grow(void);
/* Mesh paths */
int mesh_path_error_tx(u8 ttl, u8 *target, __le32 target_sn, __le16 target_rcode,
               const u8 *ra, struct ieee80211_sub_if_data *sdata);
void mesh_path_assign_nexthop(struct mesh_path *mpath, struct sta_info *sta);
void mesh_path_flush_pending(struct mesh_path *mpath);
void mesh_path_tx_pending(struct mesh_path *mpath);
int mesh_pathtbl_init(void);
void mesh_pathtbl_unregister(void);
int mesh_path_del(u8 *addr, struct ieee80211_sub_if_data *sdata);
void mesh_path_timer(unsigned long data);
void mesh_path_flush_by_nexthop(struct sta_info *sta);
void mesh_path_discard_frame(struct sk_buff *skb,
        struct ieee80211_sub_if_data *sdata);
void mesh_path_quiesce(struct ieee80211_sub_if_data *sdata);
void mesh_path_restart(struct ieee80211_sub_if_data *sdata);
void mesh_path_tx_root_frame(struct ieee80211_sub_if_data *sdata);

bool mesh_action_is_path_sel(struct ieee80211_mgmt *mgmt);
extern int mesh_paths_generation;

#ifdef CONFIG_MAC80211_MESH
extern int mesh_allocated;

static inline int mesh_plink_free_count(struct ieee80211_sub_if_data *sdata)
{
    return sdata->u.mesh.mshcfg.dot11MeshMaxPeerLinks -
           atomic_read(&sdata->u.mesh.mshstats.estab_plinks);
}

static inline bool mesh_plink_availables(struct ieee80211_sub_if_data *sdata)
{
    return (min_t(long, mesh_plink_free_count(sdata),
           MESH_MAX_PLINKS - sdata->local->num_sta)) > 0;
}

static inline void mesh_path_activate(struct mesh_path *mpath)
{
    mpath->flags |= MESH_PATH_ACTIVE | MESH_PATH_RESOLVED;
}

static inline bool mesh_path_sel_is_hwmp(struct ieee80211_sub_if_data *sdata)
{
    return sdata->u.mesh.mesh_pp_id == IEEE80211_PATH_PROTOCOL_HWMP;
}

void ieee80211_mesh_notify_scan_completed(struct ieee80211_local *local);

void ieee80211_mesh_quiesce(struct ieee80211_sub_if_data *sdata);
void ieee80211_mesh_restart(struct ieee80211_sub_if_data *sdata);
void mesh_plink_quiesce(struct sta_info *sta);
void mesh_plink_restart(struct sta_info *sta);
void mesh_path_flush_by_iface(struct ieee80211_sub_if_data *sdata);
void mesh_sync_adjust_tbtt(struct ieee80211_sub_if_data *sdata);
#else
#define mesh_allocated  0
static inline void
ieee80211_mesh_notify_scan_completed(struct ieee80211_local *local) {}
static inline void ieee80211_mesh_quiesce(struct ieee80211_sub_if_data *sdata)
{}
static inline void ieee80211_mesh_restart(struct ieee80211_sub_if_data *sdata)
{}
static inline void mesh_plink_quiesce(struct sta_info *sta) {}
static inline void mesh_plink_restart(struct sta_info *sta) {}
static inline bool mesh_path_sel_is_hwmp(struct ieee80211_sub_if_data *sdata)
{ return false; }
static inline void mesh_path_flush_by_iface(struct ieee80211_sub_if_data *sdata)
{}
#endif

#endif /* IEEE80211S_H */