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 <asm/unaligned.h> 17 #include "ieee80211_i.h" 18 19 20 /* Data structures */ 21 22 /** 23 * enum mesh_path_flags - mac80211 mesh path flags 24 * 25 * 26 * 27 * @MESH_PATH_ACTIVE: the mesh path can be used for forwarding 28 * @MESH_PATH_RESOLVING: the discovery process is running for this mesh path 29 * @MESH_PATH_SN_VALID: the mesh path contains a valid destination sequence 30 * number 31 * @MESH_PATH_FIXED: the mesh path has been manually set and should not be 32 * modified 33 * @MESH_PATH_RESOLVED: the mesh path can has been resolved 34 * 35 * MESH_PATH_RESOLVED is used by the mesh path timer to 36 * decide when to stop or cancel the mesh path discovery. 37 */ 38 enum mesh_path_flags { 39 MESH_PATH_ACTIVE = BIT(0), 40 MESH_PATH_RESOLVING = BIT(1), 41 MESH_PATH_SN_VALID = BIT(2), 42 MESH_PATH_FIXED = BIT(3), 43 MESH_PATH_RESOLVED = BIT(4), 44 }; 45 46 /** 47 * enum mesh_deferred_task_flags - mac80211 mesh deferred tasks 48 * 49 * 50 * 51 * @MESH_WORK_HOUSEKEEPING: run the periodic mesh housekeeping tasks 52 * @MESH_WORK_GROW_MPATH_TABLE: the mesh path table is full and needs 53 * to grow. 54 * @MESH_WORK_GROW_MPP_TABLE: the mesh portals table is full and needs to 55 * grow 56 * @MESH_WORK_ROOT: the mesh root station needs to send a frame 57 */ 58 enum mesh_deferred_task_flags { 59 MESH_WORK_HOUSEKEEPING, 60 MESH_WORK_GROW_MPATH_TABLE, 61 MESH_WORK_GROW_MPP_TABLE, 62 MESH_WORK_ROOT, 63 }; 64 65 /** 66 * struct mesh_path - mac80211 mesh path structure 67 * 68 * @dst: mesh path destination mac address 69 * @sdata: mesh subif 70 * @next_hop: mesh neighbor to which frames for this destination will be 71 * forwarded 72 * @timer: mesh path discovery timer 73 * @frame_queue: pending queue for frames sent to this destination while the 74 * path is unresolved 75 * @sn: target sequence number 76 * @metric: current metric to this destination 77 * @hop_count: hops to destination 78 * @exp_time: in jiffies, when the path will expire or when it expired 79 * @discovery_timeout: timeout (lapse in jiffies) used for the last discovery 80 * retry 81 * @discovery_retries: number of discovery retries 82 * @flags: mesh path flags, as specified on &enum mesh_path_flags 83 * @state_lock: mesh path state lock 84 * 85 * 86 * The combination of dst and sdata is unique in the mesh path table. Since the 87 * next_hop STA is only protected by RCU as well, deleting the STA must also 88 * remove/substitute the mesh_path structure and wait until that is no longer 89 * reachable before destroying the STA completely. 90 */ 91 struct mesh_path { 92 u8 dst[ETH_ALEN]; 93 u8 mpp[ETH_ALEN]; /* used for MPP or MAP */ 94 struct ieee80211_sub_if_data *sdata; 95 struct sta_info *next_hop; 96 struct timer_list timer; 97 struct sk_buff_head frame_queue; 98 struct rcu_head rcu; 99 u32 sn; 100 u32 metric; 101 u8 hop_count; 102 unsigned long exp_time; 103 u32 discovery_timeout; 104 u8 discovery_retries; 105 enum mesh_path_flags flags; 106 spinlock_t state_lock; 107 }; 108 109 /** 110 * struct mesh_table 111 * 112 * @hash_buckets: array of hash buckets of the table 113 * @hashwlock: array of locks to protect write operations, one per bucket 114 * @hash_mask: 2^size_order - 1, used to compute hash idx 115 * @hash_rnd: random value used for hash computations 116 * @entries: number of entries in the table 117 * @free_node: function to free nodes of the table 118 * @copy_node: fuction to copy nodes of the table 119 * @size_order: determines size of the table, there will be 2^size_order hash 120 * buckets 121 * @mean_chain_len: maximum average length for the hash buckets' list, if it is 122 * reached, the table will grow 123 */ 124 struct mesh_table { 125 /* Number of buckets will be 2^N */ 126 struct hlist_head *hash_buckets; 127 spinlock_t *hashwlock; /* One per bucket, for add/del */ 128 unsigned int hash_mask; /* (2^size_order) - 1 */ 129 __u32 hash_rnd; /* Used for hash generation */ 130 atomic_t entries; /* Up to MAX_MESH_NEIGHBOURS */ 131 void (*free_node) (struct hlist_node *p, bool free_leafs); 132 int (*copy_node) (struct hlist_node *p, struct mesh_table *newtbl); 133 int size_order; 134 int mean_chain_len; 135 }; 136 137 /* Recent multicast cache */ 138 /* RMC_BUCKETS must be a power of 2, maximum 256 */ 139 #define RMC_BUCKETS 256 140 #define RMC_QUEUE_MAX_LEN 4 141 #define RMC_TIMEOUT (3 * HZ) 142 143 /** 144 * struct rmc_entry - entry in the Recent Multicast Cache 145 * 146 * @seqnum: mesh sequence number of the frame 147 * @exp_time: expiration time of the entry, in jiffies 148 * @sa: source address of the frame 149 * 150 * The Recent Multicast Cache keeps track of the latest multicast frames that 151 * have been received by a mesh interface and discards received multicast frames 152 * that are found in the cache. 153 */ 154 struct rmc_entry { 155 struct list_head list; 156 u32 seqnum; 157 unsigned long exp_time; 158 u8 sa[ETH_ALEN]; 159 }; 160 161 struct mesh_rmc { 162 struct rmc_entry bucket[RMC_BUCKETS]; 163 u32 idx_mask; 164 }; 165 166 167 /* 168 * MESH_CFG_COMP_LEN Includes: 169 * - Active path selection protocol ID. 170 * - Active path selection metric ID. 171 * - Congestion control mode identifier. 172 * - Channel precedence. 173 * Does not include mesh capabilities, which may vary across nodes in the same 174 * mesh 175 */ 176 #define MESH_CFG_CMP_LEN (IEEE80211_MESH_CONFIG_LEN - 2) 177 178 /* Default values, timeouts in ms */ 179 #define MESH_TTL 31 180 #define MESH_MAX_RETR 3 181 #define MESH_RET_T 100 182 #define MESH_CONF_T 100 183 #define MESH_HOLD_T 100 184 185 #define MESH_PATH_TIMEOUT 5000 186 /* Minimum interval between two consecutive PREQs originated by the same 187 * interface 188 */ 189 #define MESH_PREQ_MIN_INT 10 190 #define MESH_DIAM_TRAVERSAL_TIME 50 191 /* A path will be refreshed if it is used PATH_REFRESH_TIME milliseconds before 192 * timing out. This way it will remain ACTIVE and no data frames will be 193 * unnecesarily held in the pending queue. 194 */ 195 #define MESH_PATH_REFRESH_TIME 1000 196 #define MESH_MIN_DISCOVERY_TIMEOUT (2 * MESH_DIAM_TRAVERSAL_TIME) 197 #define MESH_DEFAULT_BEACON_INTERVAL 1000 /* in 1024 us units */ 198 199 #define MESH_MAX_PREQ_RETRIES 4 200 #define MESH_PATH_EXPIRE (600 * HZ) 201 202 /* Default maximum number of established plinks per interface */ 203 #define MESH_MAX_ESTAB_PLINKS 32 204 205 /* Default maximum number of plinks per interface */ 206 #define MESH_MAX_PLINKS 256 207 208 /* Maximum number of paths per interface */ 209 #define MESH_MAX_MPATHS 1024 210 211 /* Pending ANA approval */ 212 #define MESH_PATH_SEL_ACTION 0 213 214 /* PERR reason codes */ 215 #define PEER_RCODE_UNSPECIFIED 11 216 #define PERR_RCODE_NO_ROUTE 12 217 #define PERR_RCODE_DEST_UNREACH 13 218 219 /* Public interfaces */ 220 /* Various */ 221 int ieee80211_fill_mesh_addresses(struct ieee80211_hdr *hdr, __le16 *fc, 222 const u8 *da, const u8 *sa); 223 int ieee80211_new_mesh_header(struct ieee80211s_hdr *meshhdr, 224 struct ieee80211_sub_if_data *sdata, char *addr4, 225 char *addr5, char *addr6); 226 int mesh_rmc_check(u8 *addr, struct ieee80211s_hdr *mesh_hdr, 227 struct ieee80211_sub_if_data *sdata); 228 bool mesh_matches_local(struct ieee802_11_elems *ie, 229 struct ieee80211_sub_if_data *sdata); 230 void mesh_ids_set_default(struct ieee80211_if_mesh *mesh); 231 void mesh_mgmt_ies_add(struct sk_buff *skb, 232 struct ieee80211_sub_if_data *sdata); 233 void mesh_rmc_free(struct ieee80211_sub_if_data *sdata); 234 int mesh_rmc_init(struct ieee80211_sub_if_data *sdata); 235 void ieee80211s_init(void); 236 void ieee80211s_update_metric(struct ieee80211_local *local, 237 struct sta_info *stainfo, struct sk_buff *skb); 238 void ieee80211s_stop(void); 239 void ieee80211_mesh_init_sdata(struct ieee80211_sub_if_data *sdata); 240 void ieee80211_start_mesh(struct ieee80211_sub_if_data *sdata); 241 void ieee80211_stop_mesh(struct ieee80211_sub_if_data *sdata); 242 void ieee80211_mesh_root_setup(struct ieee80211_if_mesh *ifmsh); 243 244 /* Mesh paths */ 245 int mesh_nexthop_lookup(struct sk_buff *skb, 246 struct ieee80211_sub_if_data *sdata); 247 void mesh_path_start_discovery(struct ieee80211_sub_if_data *sdata); 248 struct mesh_path *mesh_path_lookup(u8 *dst, 249 struct ieee80211_sub_if_data *sdata); 250 struct mesh_path *mpp_path_lookup(u8 *dst, 251 struct ieee80211_sub_if_data *sdata); 252 int mpp_path_add(u8 *dst, u8 *mpp, struct ieee80211_sub_if_data *sdata); 253 struct mesh_path *mesh_path_lookup_by_idx(int idx, 254 struct ieee80211_sub_if_data *sdata); 255 void mesh_path_fix_nexthop(struct mesh_path *mpath, struct sta_info *next_hop); 256 void mesh_path_expire(struct ieee80211_sub_if_data *sdata); 257 void mesh_path_flush(struct ieee80211_sub_if_data *sdata); 258 void mesh_rx_path_sel_frame(struct ieee80211_sub_if_data *sdata, 259 struct ieee80211_mgmt *mgmt, size_t len); 260 int mesh_path_add(u8 *dst, struct ieee80211_sub_if_data *sdata); 261 /* Mesh plinks */ 262 void mesh_neighbour_update(u8 *hw_addr, u32 rates, 263 struct ieee80211_sub_if_data *sdata, bool add); 264 bool mesh_peer_accepts_plinks(struct ieee802_11_elems *ie); 265 void mesh_accept_plinks_update(struct ieee80211_sub_if_data *sdata); 266 void mesh_plink_broken(struct sta_info *sta); 267 void mesh_plink_deactivate(struct sta_info *sta); 268 int mesh_plink_open(struct sta_info *sta); 269 void mesh_plink_block(struct sta_info *sta); 270 void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata, 271 struct ieee80211_mgmt *mgmt, size_t len, 272 struct ieee80211_rx_status *rx_status); 273 274 /* Private interfaces */ 275 /* Mesh tables */ 276 struct mesh_table *mesh_table_alloc(int size_order); 277 void mesh_table_free(struct mesh_table *tbl, bool free_leafs); 278 void mesh_mpath_table_grow(void); 279 void mesh_mpp_table_grow(void); 280 u32 mesh_table_hash(u8 *addr, struct ieee80211_sub_if_data *sdata, 281 struct mesh_table *tbl); 282 /* Mesh paths */ 283 int mesh_path_error_tx(u8 ttl, u8 *target, __le32 target_sn, __le16 target_rcode, 284 const u8 *ra, struct ieee80211_sub_if_data *sdata); 285 void mesh_path_assign_nexthop(struct mesh_path *mpath, struct sta_info *sta); 286 void mesh_path_flush_pending(struct mesh_path *mpath); 287 void mesh_path_tx_pending(struct mesh_path *mpath); 288 int mesh_pathtbl_init(void); 289 void mesh_pathtbl_unregister(void); 290 int mesh_path_del(u8 *addr, struct ieee80211_sub_if_data *sdata); 291 void mesh_path_timer(unsigned long data); 292 void mesh_path_flush_by_nexthop(struct sta_info *sta); 293 void mesh_path_discard_frame(struct sk_buff *skb, 294 struct ieee80211_sub_if_data *sdata); 295 void mesh_path_quiesce(struct ieee80211_sub_if_data *sdata); 296 void mesh_path_restart(struct ieee80211_sub_if_data *sdata); 297 void mesh_path_tx_root_frame(struct ieee80211_sub_if_data *sdata); 298 299 extern int mesh_paths_generation; 300 301 #ifdef CONFIG_MAC80211_MESH 302 extern int mesh_allocated; 303 304 static inline int mesh_plink_free_count(struct ieee80211_sub_if_data *sdata) 305 { 306 return sdata->u.mesh.mshcfg.dot11MeshMaxPeerLinks - 307 atomic_read(&sdata->u.mesh.mshstats.estab_plinks); 308 } 309 310 static inline bool mesh_plink_availables(struct ieee80211_sub_if_data *sdata) 311 { 312 return (min_t(long, mesh_plink_free_count(sdata), 313 MESH_MAX_PLINKS - sdata->local->num_sta)) > 0; 314 } 315 316 static inline void mesh_path_activate(struct mesh_path *mpath) 317 { 318 mpath->flags |= MESH_PATH_ACTIVE | MESH_PATH_RESOLVED; 319 } 320 321 #define for_each_mesh_entry(x, p, node, i) \ 322 for (i = 0; i <= x->hash_mask; i++) \ 323 hlist_for_each_entry_rcu(node, p, &x->hash_buckets[i], list) 324 325 void ieee80211_mesh_notify_scan_completed(struct ieee80211_local *local); 326 327 void ieee80211_mesh_quiesce(struct ieee80211_sub_if_data *sdata); 328 void ieee80211_mesh_restart(struct ieee80211_sub_if_data *sdata); 329 void mesh_plink_quiesce(struct sta_info *sta); 330 void mesh_plink_restart(struct sta_info *sta); 331 #else 332 #define mesh_allocated 0 333 static inline void 334 ieee80211_mesh_notify_scan_completed(struct ieee80211_local *local) {} 335 static inline void ieee80211_mesh_quiesce(struct ieee80211_sub_if_data *sdata) 336 {} 337 static inline void ieee80211_mesh_restart(struct ieee80211_sub_if_data *sdata) 338 {} 339 static inline void mesh_plink_quiesce(struct sta_info *sta) {} 340 static inline void mesh_plink_restart(struct sta_info *sta) {} 341 #endif 342 343 #endif /* IEEE80211S_H */ 344