net/mac80211/mesh.h

   1 /*
   2  * Copyright (c) 2008, 2009 open80211s Ltd.
   3  * Authors:    Luis Carlos Cobo <luisca@cozybit.com>
   4  *             Javier Cardona <javier@cozybit.com>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  */
  10
  11 #ifndef IEEE80211S_H
  12 #define IEEE80211S_H
  13
  14 #include <linux/types.h>
  15 #include <linux/jhash.h>
  16 #include "ieee80211_i.h"
  17
  18
  19 /* Data structures */
  20
  21 /**
  22  * enum mesh_path_flags - mac80211 mesh path flags
  23  *
  24  * @MESH_PATH_ACTIVE: the mesh path can be used for forwarding
  25  * @MESH_PATH_RESOLVING: the discovery process is running for this mesh path
  26  * @MESH_PATH_SN_VALID: the mesh path contains a valid destination sequence
  27  *      number
  28  * @MESH_PATH_FIXED: the mesh path has been manually set and should not be
  29  *      modified
  30  * @MESH_PATH_RESOLVED: the mesh path can has been resolved
  31  * @MESH_PATH_REQ_QUEUED: there is an unsent path request for this destination
  32  *      already queued up, waiting for the discovery process to start.
  33  * @MESH_PATH_DELETED: the mesh path has been deleted and should no longer
  34  *      be used
  35  *
  36  * MESH_PATH_RESOLVED is used by the mesh path timer to
  37  * decide when to stop or cancel the mesh path discovery.
  38  */
  39 enum mesh_path_flags {
  40         MESH_PATH_ACTIVE =      BIT(0),
  41         MESH_PATH_RESOLVING =   BIT(1),
  42         MESH_PATH_SN_VALID =    BIT(2),
  43         MESH_PATH_FIXED =       BIT(3),
  44         MESH_PATH_RESOLVED =    BIT(4),
  45         MESH_PATH_REQ_QUEUED =  BIT(5),
  46         MESH_PATH_DELETED =     BIT(6),
  47 };
  48
  49 /**
  50  * enum mesh_deferred_task_flags - mac80211 mesh deferred tasks
  51  *
  52  *
  53  *
  54  * @MESH_WORK_HOUSEKEEPING: run the periodic mesh housekeeping tasks
  55  * @MESH_WORK_ROOT: the mesh root station needs to send a frame
  56  * @MESH_WORK_DRIFT_ADJUST: time to compensate for clock drift relative to other
  57  * mesh nodes
  58  * @MESH_WORK_MBSS_CHANGED: rebuild beacon and notify driver of BSS changes
  59  */
  60 enum mesh_deferred_task_flags {
  61         MESH_WORK_HOUSEKEEPING,
  62         MESH_WORK_ROOT,
  63         MESH_WORK_DRIFT_ADJUST,
  64         MESH_WORK_MBSS_CHANGED,
  65 };
  66
  67 /**
  68  * struct mesh_path - mac80211 mesh path structure
  69  *
  70  * @dst: mesh path destination mac address
  71  * @mpp: mesh proxy mac address
  72  * @rhash: rhashtable list pointer
  73  * @gate_list: list pointer for known gates list
  74  * @sdata: mesh subif
  75  * @next_hop: mesh neighbor to which frames for this destination will be
  76  *      forwarded
  77  * @timer: mesh path discovery timer
  78  * @frame_queue: pending queue for frames sent to this destination while the
  79  *      path is unresolved
  80  * @rcu: rcu head for freeing mesh path
  81  * @sn: target sequence number
  82  * @metric: current metric to this destination
  83  * @hop_count: hops to destination
  84  * @exp_time: in jiffies, when the path will expire or when it expired
  85  * @discovery_timeout: timeout (lapse in jiffies) used for the last discovery
  86  *      retry
  87  * @discovery_retries: number of discovery retries
  88  * @flags: mesh path flags, as specified on &enum mesh_path_flags
  89  * @state_lock: mesh path state lock used to protect changes to the
  90  * mpath itself.  No need to take this lock when adding or removing
  91  * an mpath to a hash bucket on a path table.
  92  * @rann_snd_addr: the RANN sender address
  93  * @rann_metric: the aggregated path metric towards the root node
  94  * @last_preq_to_root: Timestamp of last PREQ sent to root
  95  * @is_root: the destination station of this path is a root node
  96  * @is_gate: the destination station of this path is a mesh gate
  97  *
  98  *
  99  * The dst address is unique in the mesh path table. Since the mesh_path is
 100  * protected by RCU, deleting the next_hop STA must remove / substitute the
 101  * mesh_path structure and wait until that is no longer reachable before
 102  * destroying the STA completely.
 103  */
 104 struct mesh_path {
 105         u8 dst[ETH_ALEN];
 106         u8 mpp[ETH_ALEN];       /* used for MPP or MAP */
 107         struct rhash_head rhash;
 108         struct hlist_node gate_list;
 109         struct ieee80211_sub_if_data *sdata;
 110         struct sta_info __rcu *next_hop;
 111         struct timer_list timer;
 112         struct sk_buff_head frame_queue;
 113         struct rcu_head rcu;
 114         u32 sn;
 115         u32 metric;
 116         u8 hop_count;
 117         unsigned long exp_time;
 118         u32 discovery_timeout;
 119         u8 discovery_retries;
 120         enum mesh_path_flags flags;
 121         spinlock_t state_lock;
 122         u8 rann_snd_addr[ETH_ALEN];
 123         u32 rann_metric;
 124         unsigned long last_preq_to_root;
 125         bool is_root;
 126         bool is_gate;
 127 };
 128
 129 /**
 130  * struct mesh_table
 131  *
 132  * @known_gates: list of known mesh gates and their mpaths by the station. The
 133  * gate's mpath may or may not be resolved and active.
 134  * @gates_lock: protects updates to known_gates
 135  * @rhead: the rhashtable containing struct mesh_paths, keyed by dest addr
 136  * @entries: number of entries in the table
 137  */
 138 struct mesh_table {
 139         struct hlist_head known_gates;
 140         spinlock_t gates_lock;
 141         struct rhashtable rhead;
 142         atomic_t entries;               /* Up to MAX_MESH_NEIGHBOURS */
 143 };
 144
 145 /* Recent multicast cache */
 146 /* RMC_BUCKETS must be a power of 2, maximum 256 */
 147 #define RMC_BUCKETS             256
 148 #define RMC_QUEUE_MAX_LEN       4
 149 #define RMC_TIMEOUT             (3 * HZ)
 150
 151 /**
 152  * struct rmc_entry - entry in the Recent Multicast Cache
 153  *
 154  * @seqnum: mesh sequence number of the frame
 155  * @exp_time: expiration time of the entry, in jiffies
 156  * @sa: source address of the frame
 157  * @list: hashtable list pointer
 158  *
 159  * The Recent Multicast Cache keeps track of the latest multicast frames that
 160  * have been received by a mesh interface and discards received multicast frames
 161  * that are found in the cache.
 162  */
 163 struct rmc_entry {
 164         struct hlist_node list;
 165         unsigned long exp_time;
 166         u32 seqnum;
 167         u8 sa[ETH_ALEN];
 168 };
 169
 170 struct mesh_rmc {
 171         struct hlist_head bucket[RMC_BUCKETS];
 172         u32 idx_mask;
 173 };
 174
 175 #define IEEE80211_MESH_HOUSEKEEPING_INTERVAL (60 * HZ)
 176
 177 #define MESH_PATH_EXPIRE (600 * HZ)
 178
 179 /* Default maximum number of plinks per interface */
 180 #define MESH_MAX_PLINKS         256
 181
 182 /* Maximum number of paths per interface */
 183 #define MESH_MAX_MPATHS         1024
 184
 185 /* Number of frames buffered per destination for unresolved destinations */
 186 #define MESH_FRAME_QUEUE_LEN    10
 187
 188 /* Public interfaces */
 189 /* Various */
 190 int ieee80211_fill_mesh_addresses(struct ieee80211_hdr *hdr, __le16 *fc,
 191                                   const u8 *da, const u8 *sa);
 192 unsigned int ieee80211_new_mesh_header(struct ieee80211_sub_if_data *sdata,
 193                                        struct ieee80211s_hdr *meshhdr,
 194                                        const char *addr4or5, const char *addr6);
 195 int mesh_rmc_check(struct ieee80211_sub_if_data *sdata,
 196                    const u8 *addr, struct ieee80211s_hdr *mesh_hdr);
 197 bool mesh_matches_local(struct ieee80211_sub_if_data *sdata,
 198                         struct ieee802_11_elems *ie);
 199 void mesh_ids_set_default(struct ieee80211_if_mesh *mesh);
 200 int mesh_add_meshconf_ie(struct ieee80211_sub_if_data *sdata,
 201                          struct sk_buff *skb);
 202 int mesh_add_meshid_ie(struct ieee80211_sub_if_data *sdata,
 203                        struct sk_buff *skb);
 204 int mesh_add_rsn_ie(struct ieee80211_sub_if_data *sdata,
 205                     struct sk_buff *skb);
 206 int mesh_add_vendor_ies(struct ieee80211_sub_if_data *sdata,
 207                         struct sk_buff *skb);
 208 int mesh_add_ht_cap_ie(struct ieee80211_sub_if_data *sdata,
 209                        struct sk_buff *skb);
 210 int mesh_add_ht_oper_ie(struct ieee80211_sub_if_data *sdata,
 211                         struct sk_buff *skb);
 212 int mesh_add_vht_cap_ie(struct ieee80211_sub_if_data *sdata,
 213                         struct sk_buff *skb);
 214 int mesh_add_vht_oper_ie(struct ieee80211_sub_if_data *sdata,
 215                          struct sk_buff *skb);
 216 void mesh_rmc_free(struct ieee80211_sub_if_data *sdata);
 217 int mesh_rmc_init(struct ieee80211_sub_if_data *sdata);
 218 void ieee80211s_init(void);
 219 void ieee80211s_update_metric(struct ieee80211_local *local,
 220                               struct sta_info *sta, struct sk_buff *skb);
 221 void ieee80211_mesh_init_sdata(struct ieee80211_sub_if_data *sdata);
 222 void ieee80211_mesh_teardown_sdata(struct ieee80211_sub_if_data *sdata);
 223 int ieee80211_start_mesh(struct ieee80211_sub_if_data *sdata);
 224 void ieee80211_stop_mesh(struct ieee80211_sub_if_data *sdata);
 225 void ieee80211_mesh_root_setup(struct ieee80211_if_mesh *ifmsh);
 226 const struct ieee80211_mesh_sync_ops *ieee80211_mesh_sync_ops_get(u8 method);
 227 /* wrapper for ieee80211_bss_info_change_notify() */
 228 void ieee80211_mbss_info_change_notify(struct ieee80211_sub_if_data *sdata,
 229                                        u32 changed);
 230
 231 /* mesh power save */
 232 u32 ieee80211_mps_local_status_update(struct ieee80211_sub_if_data *sdata);
 233 u32 ieee80211_mps_set_sta_local_pm(struct sta_info *sta,
 234                                    enum nl80211_mesh_power_mode pm);
 235 void ieee80211_mps_set_frame_flags(struct ieee80211_sub_if_data *sdata,
 236                                    struct sta_info *sta,
 237                                    struct ieee80211_hdr *hdr);
 238 void ieee80211_mps_sta_status_update(struct sta_info *sta);
 239 void ieee80211_mps_rx_h_sta_process(struct sta_info *sta,
 240                                     struct ieee80211_hdr *hdr);
 241 void ieee80211_mpsp_trigger_process(u8 *qc, struct sta_info *sta,
 242                                     bool tx, bool acked);
 243 void ieee80211_mps_frame_release(struct sta_info *sta,
 244                                  struct ieee802_11_elems *elems);
 245
 246 /* Mesh paths */
 247 int mesh_nexthop_lookup(struct ieee80211_sub_if_data *sdata,
 248                         struct sk_buff *skb);
 249 int mesh_nexthop_resolve(struct ieee80211_sub_if_data *sdata,
 250                          struct sk_buff *skb);
 251 void mesh_path_start_discovery(struct ieee80211_sub_if_data *sdata);
 252 struct mesh_path *mesh_path_lookup(struct ieee80211_sub_if_data *sdata,
 253                                    const u8 *dst);
 254 struct mesh_path *mpp_path_lookup(struct ieee80211_sub_if_data *sdata,
 255                                   const u8 *dst);
 256 int mpp_path_add(struct ieee80211_sub_if_data *sdata,
 257                  const u8 *dst, const u8 *mpp);
 258 struct mesh_path *
 259 mesh_path_lookup_by_idx(struct ieee80211_sub_if_data *sdata, int idx);
 260 struct mesh_path *
 261 mpp_path_lookup_by_idx(struct ieee80211_sub_if_data *sdata, int idx);
 262 void mesh_path_fix_nexthop(struct mesh_path *mpath, struct sta_info *next_hop);
 263 void mesh_path_expire(struct ieee80211_sub_if_data *sdata);
 264 void mesh_rx_path_sel_frame(struct ieee80211_sub_if_data *sdata,
 265                             struct ieee80211_mgmt *mgmt, size_t len);
 266 struct mesh_path *
 267 mesh_path_add(struct ieee80211_sub_if_data *sdata, const u8 *dst);
 268
 269 int mesh_path_add_gate(struct mesh_path *mpath);
 270 int mesh_path_send_to_gates(struct mesh_path *mpath);
 271 int mesh_gate_num(struct ieee80211_sub_if_data *sdata);
 272
 273 /* Mesh plinks */
 274 void mesh_neighbour_update(struct ieee80211_sub_if_data *sdata,
 275                            u8 *hw_addr, struct ieee802_11_elems *ie);
 276 bool mesh_peer_accepts_plinks(struct ieee802_11_elems *ie);
 277 u32 mesh_accept_plinks_update(struct ieee80211_sub_if_data *sdata);
 278 void mesh_plink_broken(struct sta_info *sta);
 279 u32 mesh_plink_deactivate(struct sta_info *sta);
 280 u32 mesh_plink_open(struct sta_info *sta);
 281 u32 mesh_plink_block(struct sta_info *sta);
 282 void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata,
 283                          struct ieee80211_mgmt *mgmt, size_t len,
 284                          struct ieee80211_rx_status *rx_status);
 285 void mesh_sta_cleanup(struct sta_info *sta);
 286
 287 /* Private interfaces */
 288 /* Mesh paths */
 289 int mesh_path_error_tx(struct ieee80211_sub_if_data *sdata,
 290                        u8 ttl, const u8 *target, u32 target_sn,
 291                        u16 target_rcode, const u8 *ra);
 292 void mesh_path_assign_nexthop(struct mesh_path *mpath, struct sta_info *sta);
 293 void mesh_path_flush_pending(struct mesh_path *mpath);
 294 void mesh_path_tx_pending(struct mesh_path *mpath);
 295 int mesh_pathtbl_init(struct ieee80211_sub_if_data *sdata);
 296 void mesh_pathtbl_unregister(struct ieee80211_sub_if_data *sdata);
 297 int mesh_path_del(struct ieee80211_sub_if_data *sdata, const u8 *addr);
 298 void mesh_path_timer(unsigned long data);
 299 void mesh_path_flush_by_nexthop(struct sta_info *sta);
 300 void mesh_path_discard_frame(struct ieee80211_sub_if_data *sdata,
 301                              struct sk_buff *skb);
 302 void mesh_path_tx_root_frame(struct ieee80211_sub_if_data *sdata);
 303
 304 bool mesh_action_is_path_sel(struct ieee80211_mgmt *mgmt);
 305
 306 #ifdef CONFIG_MAC80211_MESH
 307 static inline
 308 u32 mesh_plink_inc_estab_count(struct ieee80211_sub_if_data *sdata)
 309 {
 310         atomic_inc(&sdata->u.mesh.estab_plinks);
 311         return mesh_accept_plinks_update(sdata) | BSS_CHANGED_BEACON;
 312 }
 313
 314 static inline
 315 u32 mesh_plink_dec_estab_count(struct ieee80211_sub_if_data *sdata)
 316 {
 317         atomic_dec(&sdata->u.mesh.estab_plinks);
 318         return mesh_accept_plinks_update(sdata) | BSS_CHANGED_BEACON;
 319 }
 320
 321 static inline int mesh_plink_free_count(struct ieee80211_sub_if_data *sdata)
 322 {
 323         return sdata->u.mesh.mshcfg.dot11MeshMaxPeerLinks -
 324                atomic_read(&sdata->u.mesh.estab_plinks);
 325 }
 326
 327 static inline bool mesh_plink_availables(struct ieee80211_sub_if_data *sdata)
 328 {
 329         return (min_t(long, mesh_plink_free_count(sdata),
 330                    MESH_MAX_PLINKS - sdata->local->num_sta)) > 0;
 331 }
 332
 333 static inline void mesh_path_activate(struct mesh_path *mpath)
 334 {
 335         mpath->flags |= MESH_PATH_ACTIVE | MESH_PATH_RESOLVED;
 336 }
 337
 338 static inline bool mesh_path_sel_is_hwmp(struct ieee80211_sub_if_data *sdata)
 339 {
 340         return sdata->u.mesh.mesh_pp_id == IEEE80211_PATH_PROTOCOL_HWMP;
 341 }
 342
 343 void mesh_path_flush_by_iface(struct ieee80211_sub_if_data *sdata);
 344 void mesh_sync_adjust_tsf(struct ieee80211_sub_if_data *sdata);
 345 void ieee80211s_stop(void);
 346 #else
 347 static inline bool mesh_path_sel_is_hwmp(struct ieee80211_sub_if_data *sdata)
 348 { return false; }
 349 static inline void mesh_path_flush_by_iface(struct ieee80211_sub_if_data *sdata)
 350 {}
 351 static inline void ieee80211s_stop(void) {}
 352 #endif
 353
 354 #endif /* IEEE80211S_H */