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 "ieee80211_i.h" 17 18 19 /* Data structures */ 20 21 /** 22 * enum mesh_path_flags - mac80211 mesh path flags 23 * 24 * 25 * 26 * @MESH_PATH_ACTIVE: the mesh path is can be used for forwarding 27 * @MESH_PATH_RESOLVED: the discovery process is running for this mesh path 28 * @MESH_PATH_DSN_VALID: the mesh path contains a valid destination sequence 29 * number 30 * @MESH_PATH_FIXED: the mesh path has been manually set and should not be 31 * modified 32 * @MESH_PATH_RESOLVED: the mesh path can has been resolved 33 * 34 * MESH_PATH_RESOLVED and MESH_PATH_DELETE are used by the mesh path timer to 35 * decide when to stop or cancel the mesh path discovery. 36 */ 37 enum mesh_path_flags { 38 MESH_PATH_ACTIVE = BIT(0), 39 MESH_PATH_RESOLVING = BIT(1), 40 MESH_PATH_DSN_VALID = BIT(2), 41 MESH_PATH_FIXED = BIT(3), 42 MESH_PATH_RESOLVED = BIT(4), 43 }; 44 45 /** 46 * struct mesh_path - mac80211 mesh path structure 47 * 48 * @dst: mesh path destination mac address 49 * @dev: mesh path device 50 * @next_hop: mesh neighbor to which frames for this destination will be 51 * forwarded 52 * @timer: mesh path discovery timer 53 * @frame_queue: pending queue for frames sent to this destination while the 54 * path is unresolved 55 * @dsn: destination sequence number of the destination 56 * @metric: current metric to this destination 57 * @hop_count: hops to destination 58 * @exp_time: in jiffies, when the path will expire or when it expired 59 * @discovery_timeout: timeout (lapse in jiffies) used for the last discovery 60 * retry 61 * @discovery_retries: number of discovery retries 62 * @flags: mesh path flags, as specified on &enum mesh_path_flags 63 * @state_lock: mesh pat state lock 64 * 65 * 66 * The combination of dst and dev is unique in the mesh path table. Since the 67 * next_hop STA is only protected by RCU as well, deleting the STA must also 68 * remove/substitute the mesh_path structure and wait until that is no longer 69 * reachable before destroying the STA completely. 70 */ 71 struct mesh_path { 72 u8 dst[ETH_ALEN]; 73 struct net_device *dev; 74 struct sta_info *next_hop; 75 struct timer_list timer; 76 struct sk_buff_head frame_queue; 77 struct rcu_head rcu; 78 u32 dsn; 79 u32 metric; 80 u8 hop_count; 81 unsigned long exp_time; 82 u32 discovery_timeout; 83 u8 discovery_retries; 84 enum mesh_path_flags flags; 85 spinlock_t state_lock; 86 }; 87 88 /** 89 * struct mesh_table 90 * 91 * @hash_buckets: array of hash buckets of the table 92 * @hashwlock: array of locks to protect write operations, one per bucket 93 * @hash_mask: 2^size_order - 1, used to compute hash idx 94 * @hash_rnd: random value used for hash computations 95 * @entries: number of entries in the table 96 * @free_node: function to free nodes of the table 97 * @copy_node: fuction to copy nodes of the table 98 * @size_order: determines size of the table, there will be 2^size_order hash 99 * buckets 100 * @mean_chain_len: maximum average length for the hash buckets' list, if it is 101 * reached, the table will grow 102 */ 103 struct mesh_table { 104 /* Number of buckets will be 2^N */ 105 struct hlist_head *hash_buckets; 106 spinlock_t *hashwlock; /* One per bucket, for add/del */ 107 unsigned int hash_mask; /* (2^size_order) - 1 */ 108 __u32 hash_rnd; /* Used for hash generation */ 109 atomic_t entries; /* Up to MAX_MESH_NEIGHBOURS */ 110 void (*free_node) (struct hlist_node *p, bool free_leafs); 111 void (*copy_node) (struct hlist_node *p, struct mesh_table *newtbl); 112 int size_order; 113 int mean_chain_len; 114 }; 115 116 /* Recent multicast cache */ 117 /* RMC_BUCKETS must be a power of 2, maximum 256 */ 118 #define RMC_BUCKETS 256 119 #define RMC_QUEUE_MAX_LEN 4 120 #define RMC_TIMEOUT (3 * HZ) 121 122 /** 123 * struct rmc_entry - entry in the Recent Multicast Cache 124 * 125 * @seqnum: mesh sequence number of the frame 126 * @exp_time: expiration time of the entry, in jiffies 127 * @sa: source address of the frame 128 * 129 * The Recent Multicast Cache keeps track of the latest multicast frames that 130 * have been received by a mesh interface and discards received multicast frames 131 * that are found in the cache. 132 */ 133 struct rmc_entry { 134 struct list_head list; 135 u32 seqnum; 136 unsigned long exp_time; 137 u8 sa[ETH_ALEN]; 138 }; 139 140 struct mesh_rmc { 141 struct rmc_entry bucket[RMC_BUCKETS]; 142 u8 idx_mask; 143 }; 144 145 146 /* Mesh IEs constants */ 147 #define MESH_CFG_LEN 19 148 149 /* 150 * MESH_CFG_COMP_LEN Includes: 151 * - Active path selection protocol ID. 152 * - Active path selection metric ID. 153 * - Congestion control mode identifier. 154 * - Channel precedence. 155 * Does not include mesh capabilities, which may vary across nodes in the same 156 * mesh 157 */ 158 #define MESH_CFG_CMP_LEN 17 159 160 /* Default values, timeouts in ms */ 161 #define MESH_TTL 5 162 #define MESH_MAX_RETR 3 163 #define MESH_RET_T 100 164 #define MESH_CONF_T 100 165 #define MESH_HOLD_T 100 166 167 #define MESH_PATH_TIMEOUT 5000 168 /* Minimum interval between two consecutive PREQs originated by the same 169 * interface 170 */ 171 #define MESH_PREQ_MIN_INT 10 172 #define MESH_DIAM_TRAVERSAL_TIME 50 173 /* Paths will be refreshed if they are closer than PATH_REFRESH_TIME to their 174 * expiration 175 */ 176 #define MESH_PATH_REFRESH_TIME 1000 177 #define MESH_MIN_DISCOVERY_TIMEOUT (2 * MESH_DIAM_TRAVERSAL_TIME) 178 179 #define MESH_MAX_PREQ_RETRIES 4 180 #define MESH_PATH_EXPIRE (600 * HZ) 181 182 /* Default maximum number of established plinks per interface */ 183 #define MESH_MAX_ESTAB_PLINKS 32 184 185 /* Default maximum number of plinks per interface */ 186 #define MESH_MAX_PLINKS 256 187 188 /* Maximum number of paths per interface */ 189 #define MESH_MAX_MPATHS 1024 190 191 /* Pending ANA approval */ 192 #define PLINK_CATEGORY 30 193 #define MESH_PATH_SEL_CATEGORY 32 194 195 /* Mesh Header Flags */ 196 #define IEEE80211S_FLAGS_AE 0x3 197 198 /* Public interfaces */ 199 /* Various */ 200 u8 mesh_id_hash(u8 *mesh_id, int mesh_id_len); 201 int ieee80211_get_mesh_hdrlen(struct ieee80211s_hdr *meshhdr); 202 int ieee80211_new_mesh_header(struct ieee80211s_hdr *meshhdr, 203 struct ieee80211_sub_if_data *sdata); 204 int mesh_rmc_check(u8 *addr, struct ieee80211s_hdr *mesh_hdr, 205 struct net_device *dev); 206 bool mesh_matches_local(struct ieee802_11_elems *ie, struct net_device *dev); 207 void mesh_ids_set_default(struct ieee80211_if_sta *sta); 208 void mesh_mgmt_ies_add(struct sk_buff *skb, struct net_device *dev); 209 void mesh_rmc_free(struct net_device *dev); 210 int mesh_rmc_init(struct net_device *dev); 211 void ieee80211s_init(void); 212 void ieee80211s_stop(void); 213 void ieee80211_mesh_init_sdata(struct ieee80211_sub_if_data *sdata); 214 215 /* Mesh paths */ 216 int mesh_nexthop_lookup(u8 *next_hop, struct sk_buff *skb, 217 struct net_device *dev); 218 void mesh_path_start_discovery(struct net_device *dev); 219 struct mesh_path *mesh_path_lookup(u8 *dst, struct net_device *dev); 220 struct mesh_path *mesh_path_lookup_by_idx(int idx, struct net_device *dev); 221 void mesh_path_fix_nexthop(struct mesh_path *mpath, struct sta_info *next_hop); 222 void mesh_path_expire(struct net_device *dev); 223 void mesh_path_flush(struct net_device *dev); 224 void mesh_rx_path_sel_frame(struct net_device *dev, struct ieee80211_mgmt *mgmt, 225 size_t len); 226 int mesh_path_add(u8 *dst, struct net_device *dev); 227 /* Mesh plinks */ 228 void mesh_neighbour_update(u8 *hw_addr, u64 rates, struct net_device *dev, 229 bool add); 230 bool mesh_peer_accepts_plinks(struct ieee802_11_elems *ie, 231 struct net_device *dev); 232 void mesh_accept_plinks_update(struct ieee80211_sub_if_data *sdata); 233 void mesh_plink_broken(struct sta_info *sta); 234 void mesh_plink_deactivate(struct sta_info *sta); 235 int mesh_plink_open(struct sta_info *sta); 236 int mesh_plink_close(struct sta_info *sta); 237 void mesh_plink_block(struct sta_info *sta); 238 void mesh_rx_plink_frame(struct net_device *dev, struct ieee80211_mgmt *mgmt, 239 size_t len, struct ieee80211_rx_status *rx_status); 240 241 /* Private interfaces */ 242 /* Mesh tables */ 243 struct mesh_table *mesh_table_alloc(int size_order); 244 void mesh_table_free(struct mesh_table *tbl, bool free_leafs); 245 struct mesh_table *mesh_table_grow(struct mesh_table *tbl); 246 u32 mesh_table_hash(u8 *addr, struct net_device *dev, struct mesh_table *tbl); 247 /* Mesh paths */ 248 int mesh_path_error_tx(u8 *dest, __le32 dest_dsn, u8 *ra, 249 struct net_device *dev); 250 void mesh_path_assign_nexthop(struct mesh_path *mpath, struct sta_info *sta); 251 void mesh_path_flush_pending(struct mesh_path *mpath); 252 void mesh_path_tx_pending(struct mesh_path *mpath); 253 int mesh_pathtbl_init(void); 254 void mesh_pathtbl_unregister(void); 255 int mesh_path_del(u8 *addr, struct net_device *dev); 256 void mesh_path_timer(unsigned long data); 257 void mesh_path_flush_by_nexthop(struct sta_info *sta); 258 void mesh_path_discard_frame(struct sk_buff *skb, struct net_device *dev); 259 260 #ifdef CONFIG_MAC80211_MESH 261 extern int mesh_allocated; 262 263 static inline int mesh_plink_free_count(struct ieee80211_sub_if_data *sdata) 264 { 265 return sdata->u.sta.mshcfg.dot11MeshMaxPeerLinks - 266 atomic_read(&sdata->u.sta.mshstats.estab_plinks); 267 } 268 269 static inline bool mesh_plink_availables(struct ieee80211_sub_if_data *sdata) 270 { 271 return (min_t(long, mesh_plink_free_count(sdata), 272 MESH_MAX_PLINKS - sdata->local->num_sta)) > 0; 273 } 274 275 static inline void mesh_path_activate(struct mesh_path *mpath) 276 { 277 mpath->flags |= MESH_PATH_ACTIVE | MESH_PATH_RESOLVED; 278 } 279 280 #define for_each_mesh_entry(x, p, node, i) \ 281 for (i = 0; i <= x->hash_mask; i++) \ 282 hlist_for_each_entry_rcu(node, p, &x->hash_buckets[i], list) 283 284 #else 285 #define mesh_allocated 0 286 #endif 287 288 #define MESH_PREQ(skb) (skb->cb + 30) 289 290 #endif /* IEEE80211S_H */ 291