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 is can be used for forwarding 28 * @MESH_PATH_RESOLVED: 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 and MESH_PATH_DELETE are 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 * struct mesh_path - mac80211 mesh path structure 48 * 49 * @dst: mesh path destination mac address 50 * @dev: mesh path device 51 * @next_hop: mesh neighbor to which frames for this destination will be 52 * forwarded 53 * @timer: mesh path discovery timer 54 * @frame_queue: pending queue for frames sent to this destination while the 55 * path is unresolved 56 * @dsn: destination sequence number of the destination 57 * @metric: current metric to this destination 58 * @hop_count: hops to destination 59 * @exp_time: in jiffies, when the path will expire or when it expired 60 * @discovery_timeout: timeout (lapse in jiffies) used for the last discovery 61 * retry 62 * @discovery_retries: number of discovery retries 63 * @flags: mesh path flags, as specified on &enum mesh_path_flags 64 * @state_lock: mesh pat state lock 65 * 66 * 67 * The combination of dst and dev is unique in the mesh path table. Since the 68 * next_hop STA is only protected by RCU as well, deleting the STA must also 69 * remove/substitute the mesh_path structure and wait until that is no longer 70 * reachable before destroying the STA completely. 71 */ 72 struct mesh_path { 73 u8 dst[ETH_ALEN]; 74 struct net_device *dev; 75 struct sta_info *next_hop; 76 struct timer_list timer; 77 struct sk_buff_head frame_queue; 78 struct rcu_head rcu; 79 u32 dsn; 80 u32 metric; 81 u8 hop_count; 82 unsigned long exp_time; 83 u32 discovery_timeout; 84 u8 discovery_retries; 85 enum mesh_path_flags flags; 86 spinlock_t state_lock; 87 }; 88 89 /** 90 * struct mesh_table 91 * 92 * @hash_buckets: array of hash buckets of the table 93 * @hashwlock: array of locks to protect write operations, one per bucket 94 * @hash_mask: 2^size_order - 1, used to compute hash idx 95 * @hash_rnd: random value used for hash computations 96 * @entries: number of entries in the table 97 * @free_node: function to free nodes of the table 98 * @copy_node: fuction to copy nodes of the table 99 * @size_order: determines size of the table, there will be 2^size_order hash 100 * buckets 101 * @mean_chain_len: maximum average length for the hash buckets' list, if it is 102 * reached, the table will grow 103 */ 104 struct mesh_table { 105 /* Number of buckets will be 2^N */ 106 struct hlist_head *hash_buckets; 107 spinlock_t *hashwlock; /* One per bucket, for add/del */ 108 unsigned int hash_mask; /* (2^size_order) - 1 */ 109 __u32 hash_rnd; /* Used for hash generation */ 110 atomic_t entries; /* Up to MAX_MESH_NEIGHBOURS */ 111 void (*free_node) (struct hlist_node *p, bool free_leafs); 112 int (*copy_node) (struct hlist_node *p, struct mesh_table *newtbl); 113 int size_order; 114 int mean_chain_len; 115 }; 116 117 /* Recent multicast cache */ 118 /* RMC_BUCKETS must be a power of 2, maximum 256 */ 119 #define RMC_BUCKETS 256 120 #define RMC_QUEUE_MAX_LEN 4 121 #define RMC_TIMEOUT (3 * HZ) 122 123 /** 124 * struct rmc_entry - entry in the Recent Multicast Cache 125 * 126 * @seqnum: mesh sequence number of the frame 127 * @exp_time: expiration time of the entry, in jiffies 128 * @sa: source address of the frame 129 * 130 * The Recent Multicast Cache keeps track of the latest multicast frames that 131 * have been received by a mesh interface and discards received multicast frames 132 * that are found in the cache. 133 */ 134 struct rmc_entry { 135 struct list_head list; 136 u32 seqnum; 137 unsigned long exp_time; 138 u8 sa[ETH_ALEN]; 139 }; 140 141 struct mesh_rmc { 142 struct rmc_entry bucket[RMC_BUCKETS]; 143 u32 idx_mask; 144 }; 145 146 147 /* Mesh IEs constants */ 148 #define MESH_CFG_LEN 19 149 150 /* 151 * MESH_CFG_COMP_LEN Includes: 152 * - Active path selection protocol ID. 153 * - Active path selection metric ID. 154 * - Congestion control mode identifier. 155 * - Channel precedence. 156 * Does not include mesh capabilities, which may vary across nodes in the same 157 * mesh 158 */ 159 #define MESH_CFG_CMP_LEN 17 160 161 /* Default values, timeouts in ms */ 162 #define MESH_TTL 5 163 #define MESH_MAX_RETR 3 164 #define MESH_RET_T 100 165 #define MESH_CONF_T 100 166 #define MESH_HOLD_T 100 167 168 #define MESH_PATH_TIMEOUT 5000 169 /* Minimum interval between two consecutive PREQs originated by the same 170 * interface 171 */ 172 #define MESH_PREQ_MIN_INT 10 173 #define MESH_DIAM_TRAVERSAL_TIME 50 174 /* Paths will be refreshed if they are closer than PATH_REFRESH_TIME to their 175 * expiration 176 */ 177 #define MESH_PATH_REFRESH_TIME 1000 178 #define MESH_MIN_DISCOVERY_TIMEOUT (2 * MESH_DIAM_TRAVERSAL_TIME) 179 180 #define MESH_MAX_PREQ_RETRIES 4 181 #define MESH_PATH_EXPIRE (600 * HZ) 182 183 /* Default maximum number of established plinks per interface */ 184 #define MESH_MAX_ESTAB_PLINKS 32 185 186 /* Default maximum number of plinks per interface */ 187 #define MESH_MAX_PLINKS 256 188 189 /* Maximum number of paths per interface */ 190 #define MESH_MAX_MPATHS 1024 191 192 /* Pending ANA approval */ 193 #define PLINK_CATEGORY 30 194 #define MESH_PATH_SEL_CATEGORY 32 195 196 /* Mesh Header Flags */ 197 #define IEEE80211S_FLAGS_AE 0x3 198 199 /* Public interfaces */ 200 /* Various */ 201 u8 mesh_id_hash(u8 *mesh_id, int mesh_id_len); 202 int ieee80211_get_mesh_hdrlen(struct ieee80211s_hdr *meshhdr); 203 int ieee80211_new_mesh_header(struct ieee80211s_hdr *meshhdr, 204 struct ieee80211_sub_if_data *sdata); 205 int mesh_rmc_check(u8 *addr, struct ieee80211s_hdr *mesh_hdr, 206 struct net_device *dev); 207 bool mesh_matches_local(struct ieee802_11_elems *ie, struct net_device *dev); 208 void mesh_ids_set_default(struct ieee80211_if_sta *sta); 209 void mesh_mgmt_ies_add(struct sk_buff *skb, struct net_device *dev); 210 void mesh_rmc_free(struct net_device *dev); 211 int mesh_rmc_init(struct net_device *dev); 212 void ieee80211s_init(void); 213 void ieee80211s_stop(void); 214 void ieee80211_mesh_init_sdata(struct ieee80211_sub_if_data *sdata); 215 216 /* Mesh paths */ 217 int mesh_nexthop_lookup(u8 *next_hop, struct sk_buff *skb, 218 struct net_device *dev); 219 void mesh_path_start_discovery(struct net_device *dev); 220 struct mesh_path *mesh_path_lookup(u8 *dst, struct net_device *dev); 221 struct mesh_path *mesh_path_lookup_by_idx(int idx, struct net_device *dev); 222 void mesh_path_fix_nexthop(struct mesh_path *mpath, struct sta_info *next_hop); 223 void mesh_path_expire(struct net_device *dev); 224 void mesh_path_flush(struct net_device *dev); 225 void mesh_rx_path_sel_frame(struct net_device *dev, struct ieee80211_mgmt *mgmt, 226 size_t len); 227 int mesh_path_add(u8 *dst, struct net_device *dev); 228 /* Mesh plinks */ 229 void mesh_neighbour_update(u8 *hw_addr, u64 rates, struct net_device *dev, 230 bool add); 231 bool mesh_peer_accepts_plinks(struct ieee802_11_elems *ie, 232 struct net_device *dev); 233 void mesh_accept_plinks_update(struct ieee80211_sub_if_data *sdata); 234 void mesh_plink_broken(struct sta_info *sta); 235 void mesh_plink_deactivate(struct sta_info *sta); 236 int mesh_plink_open(struct sta_info *sta); 237 int mesh_plink_close(struct sta_info *sta); 238 void mesh_plink_block(struct sta_info *sta); 239 void mesh_rx_plink_frame(struct net_device *dev, struct ieee80211_mgmt *mgmt, 240 size_t len, struct ieee80211_rx_status *rx_status); 241 242 /* Private interfaces */ 243 /* Mesh tables */ 244 struct mesh_table *mesh_table_alloc(int size_order); 245 void mesh_table_free(struct mesh_table *tbl, bool free_leafs); 246 struct mesh_table *mesh_table_grow(struct mesh_table *tbl); 247 u32 mesh_table_hash(u8 *addr, struct net_device *dev, struct mesh_table *tbl); 248 /* Mesh paths */ 249 int mesh_path_error_tx(u8 *dest, __le32 dest_dsn, u8 *ra, 250 struct net_device *dev); 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 net_device *dev); 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, struct net_device *dev); 260 261 #ifdef CONFIG_MAC80211_MESH 262 extern int mesh_allocated; 263 264 static inline int mesh_plink_free_count(struct ieee80211_sub_if_data *sdata) 265 { 266 return sdata->u.sta.mshcfg.dot11MeshMaxPeerLinks - 267 atomic_read(&sdata->u.sta.mshstats.estab_plinks); 268 } 269 270 static inline bool mesh_plink_availables(struct ieee80211_sub_if_data *sdata) 271 { 272 return (min_t(long, mesh_plink_free_count(sdata), 273 MESH_MAX_PLINKS - sdata->local->num_sta)) > 0; 274 } 275 276 static inline void mesh_path_activate(struct mesh_path *mpath) 277 { 278 mpath->flags |= MESH_PATH_ACTIVE | MESH_PATH_RESOLVED; 279 } 280 281 #define for_each_mesh_entry(x, p, node, i) \ 282 for (i = 0; i <= x->hash_mask; i++) \ 283 hlist_for_each_entry_rcu(node, p, &x->hash_buckets[i], list) 284 285 #else 286 #define mesh_allocated 0 287 #endif 288 289 #define MESH_PREQ(skb) (skb->cb + 30) 290 291 #endif /* IEEE80211S_H */ 292