mesh.h

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/*
 * Copyright (c) 2008, 2009 open80211s Ltd.
 * Authors:    Luis Carlos Cobo <luisca@cozybit.com>
 *             Javier Cardona <javier@cozybit.com>
 *
 * 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 <asm/unaligned.h>
#include "ieee80211_i.h"


/* Data structures */

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),
};

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

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;
        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

/* 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 ieee802_11_elems *ie,
                struct ieee80211_sub_if_data *sdata);
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);
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 *stainfo, 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);

/* Mesh paths */
int mesh_nexthop_lookup(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(u8 *hw_addr, u32 rates,
                struct ieee80211_sub_if_data *sdata,
                struct ieee802_11_elems *ie);
bool mesh_peer_accepts_plinks(struct ieee802_11_elems *ie);
void 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_flush_by_iface(struct ieee80211_sub_if_data *sdata);
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);
#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; }
#endif

#endif /* IEEE80211S_H */