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 __rcu *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: function 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 * rcu_head: RCU head to free the table 124 */ 125 struct mesh_table { 126 /* Number of buckets will be 2^N */ 127 struct hlist_head *hash_buckets; 128 spinlock_t *hashwlock; /* One per bucket, for add/del */ 129 unsigned int hash_mask; /* (2^size_order) - 1 */ 130 __u32 hash_rnd; /* Used for hash generation */ 131 atomic_t entries; /* Up to MAX_MESH_NEIGHBOURS */ 132 void (*free_node) (struct hlist_node *p, bool free_leafs); 133 int (*copy_node) (struct hlist_node *p, struct mesh_table *newtbl); 134 int size_order; 135 int mean_chain_len; 136 137 struct rcu_head rcu_head; 138 }; 139 140 /* Recent multicast cache */ 141 /* RMC_BUCKETS must be a power of 2, maximum 256 */ 142 #define RMC_BUCKETS 256 143 #define RMC_QUEUE_MAX_LEN 4 144 #define RMC_TIMEOUT (3 * HZ) 145 146 /** 147 * struct rmc_entry - entry in the Recent Multicast Cache 148 * 149 * @seqnum: mesh sequence number of the frame 150 * @exp_time: expiration time of the entry, in jiffies 151 * @sa: source address of the frame 152 * 153 * The Recent Multicast Cache keeps track of the latest multicast frames that 154 * have been received by a mesh interface and discards received multicast frames 155 * that are found in the cache. 156 */ 157 struct rmc_entry { 158 struct list_head list; 159 u32 seqnum; 160 unsigned long exp_time; 161 u8 sa[ETH_ALEN]; 162 }; 163 164 struct mesh_rmc { 165 struct rmc_entry bucket[RMC_BUCKETS]; 166 u32 idx_mask; 167 }; 168 169 170 #define MESH_DEFAULT_BEACON_INTERVAL 1000 /* in 1024 us units */ 171 172 #define MESH_PATH_EXPIRE (600 * HZ) 173 174 /* Default maximum number of plinks per interface */ 175 #define MESH_MAX_PLINKS 256 176 177 /* Maximum number of paths per interface */ 178 #define MESH_MAX_MPATHS 1024 179 180 /* Pending ANA approval */ 181 #define MESH_PATH_SEL_ACTION 0 182 183 /* PERR reason codes */ 184 #define PEER_RCODE_UNSPECIFIED 11 185 #define PERR_RCODE_NO_ROUTE 12 186 #define PERR_RCODE_DEST_UNREACH 13 187 188 /* Public interfaces */ 189 /* Various */ 190 int ieee80211_fill_mesh_addresses(struct ieee80211_hdr *hdr, __le16 *fc, 191 const u8 *da, const u8 *sa); 192 int ieee80211_new_mesh_header(struct ieee80211s_hdr *meshhdr, 193 struct ieee80211_sub_if_data *sdata, char *addr4or5, 194 char *addr6); 195 int mesh_rmc_check(u8 *addr, struct ieee80211s_hdr *mesh_hdr, 196 struct ieee80211_sub_if_data *sdata); 197 bool mesh_matches_local(struct ieee802_11_elems *ie, 198 struct ieee80211_sub_if_data *sdata); 199 void mesh_ids_set_default(struct ieee80211_if_mesh *mesh); 200 void mesh_mgmt_ies_add(struct sk_buff *skb, 201 struct ieee80211_sub_if_data *sdata); 202 void mesh_rmc_free(struct ieee80211_sub_if_data *sdata); 203 int mesh_rmc_init(struct ieee80211_sub_if_data *sdata); 204 void ieee80211s_init(void); 205 void ieee80211s_update_metric(struct ieee80211_local *local, 206 struct sta_info *stainfo, struct sk_buff *skb); 207 void ieee80211s_stop(void); 208 void ieee80211_mesh_init_sdata(struct ieee80211_sub_if_data *sdata); 209 void ieee80211_start_mesh(struct ieee80211_sub_if_data *sdata); 210 void ieee80211_stop_mesh(struct ieee80211_sub_if_data *sdata); 211 void ieee80211_mesh_root_setup(struct ieee80211_if_mesh *ifmsh); 212 213 /* Mesh paths */ 214 int mesh_nexthop_lookup(struct sk_buff *skb, 215 struct ieee80211_sub_if_data *sdata); 216 void mesh_path_start_discovery(struct ieee80211_sub_if_data *sdata); 217 struct mesh_path *mesh_path_lookup(u8 *dst, 218 struct ieee80211_sub_if_data *sdata); 219 struct mesh_path *mpp_path_lookup(u8 *dst, 220 struct ieee80211_sub_if_data *sdata); 221 int mpp_path_add(u8 *dst, u8 *mpp, struct ieee80211_sub_if_data *sdata); 222 struct mesh_path *mesh_path_lookup_by_idx(int idx, 223 struct ieee80211_sub_if_data *sdata); 224 void mesh_path_fix_nexthop(struct mesh_path *mpath, struct sta_info *next_hop); 225 void mesh_path_expire(struct ieee80211_sub_if_data *sdata); 226 void mesh_path_flush(struct ieee80211_sub_if_data *sdata); 227 void mesh_rx_path_sel_frame(struct ieee80211_sub_if_data *sdata, 228 struct ieee80211_mgmt *mgmt, size_t len); 229 int mesh_path_add(u8 *dst, struct ieee80211_sub_if_data *sdata); 230 /* Mesh plinks */ 231 void mesh_neighbour_update(u8 *hw_addr, u32 rates, 232 struct ieee80211_sub_if_data *sdata, 233 struct ieee802_11_elems *ie); 234 bool mesh_peer_accepts_plinks(struct ieee802_11_elems *ie); 235 void mesh_accept_plinks_update(struct ieee80211_sub_if_data *sdata); 236 void mesh_plink_broken(struct sta_info *sta); 237 void mesh_plink_deactivate(struct sta_info *sta); 238 int mesh_plink_open(struct sta_info *sta); 239 void mesh_plink_block(struct sta_info *sta); 240 void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata, 241 struct ieee80211_mgmt *mgmt, size_t len, 242 struct ieee80211_rx_status *rx_status); 243 244 /* Private interfaces */ 245 /* Mesh tables */ 246 void mesh_mpath_table_grow(void); 247 void mesh_mpp_table_grow(void); 248 /* Mesh paths */ 249 int mesh_path_error_tx(u8 ttl, u8 *target, __le32 target_sn, __le16 target_rcode, 250 const u8 *ra, struct ieee80211_sub_if_data *sdata); 251 void mesh_path_assign_nexthop(struct mesh_path *mpath, struct sta_info *sta); 252 void mesh_path_flush_pending(struct mesh_path *mpath); 253 void mesh_path_tx_pending(struct mesh_path *mpath); 254 int mesh_pathtbl_init(void); 255 void mesh_pathtbl_unregister(void); 256 int mesh_path_del(u8 *addr, struct ieee80211_sub_if_data *sdata); 257 void mesh_path_timer(unsigned long data); 258 void mesh_path_flush_by_nexthop(struct sta_info *sta); 259 void mesh_path_discard_frame(struct sk_buff *skb, 260 struct ieee80211_sub_if_data *sdata); 261 void mesh_path_quiesce(struct ieee80211_sub_if_data *sdata); 262 void mesh_path_restart(struct ieee80211_sub_if_data *sdata); 263 void mesh_path_tx_root_frame(struct ieee80211_sub_if_data *sdata); 264 265 extern int mesh_paths_generation; 266 267 #ifdef CONFIG_MAC80211_MESH 268 extern int mesh_allocated; 269 270 static inline int mesh_plink_free_count(struct ieee80211_sub_if_data *sdata) 271 { 272 return sdata->u.mesh.mshcfg.dot11MeshMaxPeerLinks - 273 atomic_read(&sdata->u.mesh.mshstats.estab_plinks); 274 } 275 276 static inline bool mesh_plink_availables(struct ieee80211_sub_if_data *sdata) 277 { 278 return (min_t(long, mesh_plink_free_count(sdata), 279 MESH_MAX_PLINKS - sdata->local->num_sta)) > 0; 280 } 281 282 static inline void mesh_path_activate(struct mesh_path *mpath) 283 { 284 mpath->flags |= MESH_PATH_ACTIVE | MESH_PATH_RESOLVED; 285 } 286 287 static inline bool mesh_path_sel_is_hwmp(struct ieee80211_sub_if_data *sdata) 288 { 289 return sdata->u.mesh.mesh_pp_id == IEEE80211_PATH_PROTOCOL_HWMP; 290 } 291 292 void ieee80211_mesh_notify_scan_completed(struct ieee80211_local *local); 293 294 void ieee80211_mesh_quiesce(struct ieee80211_sub_if_data *sdata); 295 void ieee80211_mesh_restart(struct ieee80211_sub_if_data *sdata); 296 void mesh_plink_quiesce(struct sta_info *sta); 297 void mesh_plink_restart(struct sta_info *sta); 298 #else 299 #define mesh_allocated 0 300 static inline void 301 ieee80211_mesh_notify_scan_completed(struct ieee80211_local *local) {} 302 static inline void ieee80211_mesh_quiesce(struct ieee80211_sub_if_data *sdata) 303 {} 304 static inline void ieee80211_mesh_restart(struct ieee80211_sub_if_data *sdata) 305 {} 306 static inline void mesh_plink_quiesce(struct sta_info *sta) {} 307 static inline void mesh_plink_restart(struct sta_info *sta) {} 308 static inline bool mesh_path_sel_is_hwmp(struct ieee80211_sub_if_data *sdata) 309 { return false; } 310 #endif 311 312 #endif /* IEEE80211S_H */ 313