1 /* 2 * Copyright (c) 2008 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_DSN_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_DSN_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 */ 57 enum mesh_deferred_task_flags { 58 MESH_WORK_HOUSEKEEPING, 59 MESH_WORK_GROW_MPATH_TABLE, 60 MESH_WORK_GROW_MPP_TABLE, 61 }; 62 63 /** 64 * struct mesh_path - mac80211 mesh path structure 65 * 66 * @dst: mesh path destination mac address 67 * @sdata: mesh subif 68 * @next_hop: mesh neighbor to which frames for this destination will be 69 * forwarded 70 * @timer: mesh path discovery timer 71 * @frame_queue: pending queue for frames sent to this destination while the 72 * path is unresolved 73 * @dsn: destination sequence number of the destination 74 * @metric: current metric to this destination 75 * @hop_count: hops to destination 76 * @exp_time: in jiffies, when the path will expire or when it expired 77 * @discovery_timeout: timeout (lapse in jiffies) used for the last discovery 78 * retry 79 * @discovery_retries: number of discovery retries 80 * @flags: mesh path flags, as specified on &enum mesh_path_flags 81 * @state_lock: mesh path state lock 82 * 83 * 84 * The combination of dst and sdata is unique in the mesh path table. Since the 85 * next_hop STA is only protected by RCU as well, deleting the STA must also 86 * remove/substitute the mesh_path structure and wait until that is no longer 87 * reachable before destroying the STA completely. 88 */ 89 struct mesh_path { 90 u8 dst[ETH_ALEN]; 91 u8 mpp[ETH_ALEN]; /* used for MPP or MAP */ 92 struct ieee80211_sub_if_data *sdata; 93 struct sta_info *next_hop; 94 struct timer_list timer; 95 struct sk_buff_head frame_queue; 96 struct rcu_head rcu; 97 u32 dsn; 98 u32 metric; 99 u8 hop_count; 100 unsigned long exp_time; 101 u32 discovery_timeout; 102 u8 discovery_retries; 103 enum mesh_path_flags flags; 104 spinlock_t state_lock; 105 }; 106 107 /** 108 * struct mesh_table 109 * 110 * @hash_buckets: array of hash buckets of the table 111 * @hashwlock: array of locks to protect write operations, one per bucket 112 * @hash_mask: 2^size_order - 1, used to compute hash idx 113 * @hash_rnd: random value used for hash computations 114 * @entries: number of entries in the table 115 * @free_node: function to free nodes of the table 116 * @copy_node: fuction to copy nodes of the table 117 * @size_order: determines size of the table, there will be 2^size_order hash 118 * buckets 119 * @mean_chain_len: maximum average length for the hash buckets' list, if it is 120 * reached, the table will grow 121 */ 122 struct mesh_table { 123 /* Number of buckets will be 2^N */ 124 struct hlist_head *hash_buckets; 125 spinlock_t *hashwlock; /* One per bucket, for add/del */ 126 unsigned int hash_mask; /* (2^size_order) - 1 */ 127 __u32 hash_rnd; /* Used for hash generation */ 128 atomic_t entries; /* Up to MAX_MESH_NEIGHBOURS */ 129 void (*free_node) (struct hlist_node *p, bool free_leafs); 130 int (*copy_node) (struct hlist_node *p, struct mesh_table *newtbl); 131 int size_order; 132 int mean_chain_len; 133 }; 134 135 /* Recent multicast cache */ 136 /* RMC_BUCKETS must be a power of 2, maximum 256 */ 137 #define RMC_BUCKETS 256 138 #define RMC_QUEUE_MAX_LEN 4 139 #define RMC_TIMEOUT (3 * HZ) 140 141 /** 142 * struct rmc_entry - entry in the Recent Multicast Cache 143 * 144 * @seqnum: mesh sequence number of the frame 145 * @exp_time: expiration time of the entry, in jiffies 146 * @sa: source address of the frame 147 * 148 * The Recent Multicast Cache keeps track of the latest multicast frames that 149 * have been received by a mesh interface and discards received multicast frames 150 * that are found in the cache. 151 */ 152 struct rmc_entry { 153 struct list_head list; 154 u32 seqnum; 155 unsigned long exp_time; 156 u8 sa[ETH_ALEN]; 157 }; 158 159 struct mesh_rmc { 160 struct rmc_entry bucket[RMC_BUCKETS]; 161 u32 idx_mask; 162 }; 163 164 165 /* 166 * MESH_CFG_COMP_LEN Includes: 167 * - Active path selection protocol ID. 168 * - Active path selection metric ID. 169 * - Congestion control mode identifier. 170 * - Channel precedence. 171 * Does not include mesh capabilities, which may vary across nodes in the same 172 * mesh 173 */ 174 #define MESH_CFG_CMP_LEN (IEEE80211_MESH_CONFIG_LEN - 2) 175 176 /* Default values, timeouts in ms */ 177 #define MESH_TTL 5 178 #define MESH_MAX_RETR 3 179 #define MESH_RET_T 100 180 #define MESH_CONF_T 100 181 #define MESH_HOLD_T 100 182 183 #define MESH_PATH_TIMEOUT 5000 184 /* Minimum interval between two consecutive PREQs originated by the same 185 * interface 186 */ 187 #define MESH_PREQ_MIN_INT 10 188 #define MESH_DIAM_TRAVERSAL_TIME 50 189 /* Paths will be refreshed if they are closer than PATH_REFRESH_TIME to their 190 * expiration 191 */ 192 #define MESH_PATH_REFRESH_TIME 1000 193 #define MESH_MIN_DISCOVERY_TIMEOUT (2 * MESH_DIAM_TRAVERSAL_TIME) 194 #define MESH_DEFAULT_BEACON_INTERVAL 1000 /* in 1024 us units */ 195 196 #define MESH_MAX_PREQ_RETRIES 4 197 #define MESH_PATH_EXPIRE (600 * HZ) 198 199 /* Default maximum number of established plinks per interface */ 200 #define MESH_MAX_ESTAB_PLINKS 32 201 202 /* Default maximum number of plinks per interface */ 203 #define MESH_MAX_PLINKS 256 204 205 /* Maximum number of paths per interface */ 206 #define MESH_MAX_MPATHS 1024 207 208 /* Pending ANA approval */ 209 #define PLINK_CATEGORY 30 210 #define MESH_PATH_SEL_CATEGORY 32 211 212 /* Public interfaces */ 213 /* Various */ 214 int ieee80211_fill_mesh_addresses(struct ieee80211_hdr *hdr, __le16 *fc, 215 char *da, char *sa); 216 int ieee80211_new_mesh_header(struct ieee80211s_hdr *meshhdr, 217 struct ieee80211_sub_if_data *sdata, char *addr4, 218 char *addr5, char *addr6); 219 int mesh_rmc_check(u8 *addr, struct ieee80211s_hdr *mesh_hdr, 220 struct ieee80211_sub_if_data *sdata); 221 bool mesh_matches_local(struct ieee802_11_elems *ie, 222 struct ieee80211_sub_if_data *sdata); 223 void mesh_ids_set_default(struct ieee80211_if_mesh *mesh); 224 void mesh_mgmt_ies_add(struct sk_buff *skb, 225 struct ieee80211_sub_if_data *sdata); 226 void mesh_rmc_free(struct ieee80211_sub_if_data *sdata); 227 int mesh_rmc_init(struct ieee80211_sub_if_data *sdata); 228 void ieee80211s_init(void); 229 void ieee80211s_update_metric(struct ieee80211_local *local, 230 struct sta_info *stainfo, struct sk_buff *skb); 231 void ieee80211s_stop(void); 232 void ieee80211_mesh_init_sdata(struct ieee80211_sub_if_data *sdata); 233 ieee80211_rx_result 234 ieee80211_mesh_rx_mgmt(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb); 235 void ieee80211_start_mesh(struct ieee80211_sub_if_data *sdata); 236 void ieee80211_stop_mesh(struct ieee80211_sub_if_data *sdata); 237 238 /* Mesh paths */ 239 int mesh_nexthop_lookup(struct sk_buff *skb, 240 struct ieee80211_sub_if_data *sdata); 241 void mesh_path_start_discovery(struct ieee80211_sub_if_data *sdata); 242 struct mesh_path *mesh_path_lookup(u8 *dst, 243 struct ieee80211_sub_if_data *sdata); 244 struct mesh_path *mpp_path_lookup(u8 *dst, 245 struct ieee80211_sub_if_data *sdata); 246 int mpp_path_add(u8 *dst, u8 *mpp, struct ieee80211_sub_if_data *sdata); 247 struct mesh_path *mesh_path_lookup_by_idx(int idx, 248 struct ieee80211_sub_if_data *sdata); 249 void mesh_path_fix_nexthop(struct mesh_path *mpath, struct sta_info *next_hop); 250 void mesh_path_expire(struct ieee80211_sub_if_data *sdata); 251 void mesh_path_flush(struct ieee80211_sub_if_data *sdata); 252 void mesh_rx_path_sel_frame(struct ieee80211_sub_if_data *sdata, 253 struct ieee80211_mgmt *mgmt, size_t len); 254 int mesh_path_add(u8 *dst, struct ieee80211_sub_if_data *sdata); 255 /* Mesh plinks */ 256 void mesh_neighbour_update(u8 *hw_addr, u32 rates, 257 struct ieee80211_sub_if_data *sdata, bool add); 258 bool mesh_peer_accepts_plinks(struct ieee802_11_elems *ie); 259 void mesh_accept_plinks_update(struct ieee80211_sub_if_data *sdata); 260 void mesh_plink_broken(struct sta_info *sta); 261 void mesh_plink_deactivate(struct sta_info *sta); 262 int mesh_plink_open(struct sta_info *sta); 263 void mesh_plink_block(struct sta_info *sta); 264 void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata, 265 struct ieee80211_mgmt *mgmt, size_t len, 266 struct ieee80211_rx_status *rx_status); 267 268 /* Private interfaces */ 269 /* Mesh tables */ 270 struct mesh_table *mesh_table_alloc(int size_order); 271 void mesh_table_free(struct mesh_table *tbl, bool free_leafs); 272 void mesh_mpath_table_grow(void); 273 void mesh_mpp_table_grow(void); 274 u32 mesh_table_hash(u8 *addr, struct ieee80211_sub_if_data *sdata, 275 struct mesh_table *tbl); 276 /* Mesh paths */ 277 int mesh_path_error_tx(u8 *dest, __le32 dest_dsn, u8 *ra, 278 struct ieee80211_sub_if_data *sdata); 279 void mesh_path_assign_nexthop(struct mesh_path *mpath, struct sta_info *sta); 280 void mesh_path_flush_pending(struct mesh_path *mpath); 281 void mesh_path_tx_pending(struct mesh_path *mpath); 282 int mesh_pathtbl_init(void); 283 void mesh_pathtbl_unregister(void); 284 int mesh_path_del(u8 *addr, struct ieee80211_sub_if_data *sdata); 285 void mesh_path_timer(unsigned long data); 286 void mesh_path_flush_by_nexthop(struct sta_info *sta); 287 void mesh_path_discard_frame(struct sk_buff *skb, 288 struct ieee80211_sub_if_data *sdata); 289 void mesh_path_quiesce(struct ieee80211_sub_if_data *sdata); 290 void mesh_path_restart(struct ieee80211_sub_if_data *sdata); 291 292 extern int mesh_paths_generation; 293 294 #ifdef CONFIG_MAC80211_MESH 295 extern int mesh_allocated; 296 297 static inline int mesh_plink_free_count(struct ieee80211_sub_if_data *sdata) 298 { 299 return sdata->u.mesh.mshcfg.dot11MeshMaxPeerLinks - 300 atomic_read(&sdata->u.mesh.mshstats.estab_plinks); 301 } 302 303 static inline bool mesh_plink_availables(struct ieee80211_sub_if_data *sdata) 304 { 305 return (min_t(long, mesh_plink_free_count(sdata), 306 MESH_MAX_PLINKS - sdata->local->num_sta)) > 0; 307 } 308 309 static inline void mesh_path_activate(struct mesh_path *mpath) 310 { 311 mpath->flags |= MESH_PATH_ACTIVE | MESH_PATH_RESOLVED; 312 } 313 314 #define for_each_mesh_entry(x, p, node, i) \ 315 for (i = 0; i <= x->hash_mask; i++) \ 316 hlist_for_each_entry_rcu(node, p, &x->hash_buckets[i], list) 317 318 void ieee80211_mesh_notify_scan_completed(struct ieee80211_local *local); 319 320 void ieee80211_mesh_quiesce(struct ieee80211_sub_if_data *sdata); 321 void ieee80211_mesh_restart(struct ieee80211_sub_if_data *sdata); 322 void mesh_plink_quiesce(struct sta_info *sta); 323 void mesh_plink_restart(struct sta_info *sta); 324 #else 325 #define mesh_allocated 0 326 static inline void 327 ieee80211_mesh_notify_scan_completed(struct ieee80211_local *local) {} 328 static inline void ieee80211_mesh_quiesce(struct ieee80211_sub_if_data *sdata) 329 {} 330 static inline void ieee80211_mesh_restart(struct ieee80211_sub_if_data *sdata) 331 {} 332 static inline void mesh_plink_quiesce(struct sta_info *sta) {} 333 static inline void mesh_plink_restart(struct sta_info *sta) {} 334 #endif 335 336 #endif /* IEEE80211S_H */ 337