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 */ 38enum 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 */ 58enum 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 */ 91struct 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 */ 124struct 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 */ 154struct rmc_entry { 155 struct list_head list; 156 u32 seqnum; 157 unsigned long exp_time; 158 u8 sa[ETH_ALEN]; 159}; 160 161struct 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 */ 221int ieee80211_fill_mesh_addresses(struct ieee80211_hdr *hdr, __le16 *fc, 222 const u8 *da, const u8 *sa); 223int ieee80211_new_mesh_header(struct ieee80211s_hdr *meshhdr, 224 struct ieee80211_sub_if_data *sdata, char *addr4, 225 char *addr5, char *addr6); 226int mesh_rmc_check(u8 *addr, struct ieee80211s_hdr *mesh_hdr, 227 struct ieee80211_sub_if_data *sdata); 228bool mesh_matches_local(struct ieee802_11_elems *ie, 229 struct ieee80211_sub_if_data *sdata); 230void mesh_ids_set_default(struct ieee80211_if_mesh *mesh); 231void mesh_mgmt_ies_add(struct sk_buff *skb, 232 struct ieee80211_sub_if_data *sdata); 233void mesh_rmc_free(struct ieee80211_sub_if_data *sdata); 234int mesh_rmc_init(struct ieee80211_sub_if_data *sdata); 235void ieee80211s_init(void); 236void ieee80211s_update_metric(struct ieee80211_local *local, 237 struct sta_info *stainfo, struct sk_buff *skb); 238void ieee80211s_stop(void); 239void ieee80211_mesh_init_sdata(struct ieee80211_sub_if_data *sdata); 240void ieee80211_start_mesh(struct ieee80211_sub_if_data *sdata); 241void ieee80211_stop_mesh(struct ieee80211_sub_if_data *sdata); 242void ieee80211_mesh_root_setup(struct ieee80211_if_mesh *ifmsh); 243 244/* Mesh paths */ 245int mesh_nexthop_lookup(struct sk_buff *skb, 246 struct ieee80211_sub_if_data *sdata); 247void mesh_path_start_discovery(struct ieee80211_sub_if_data *sdata); 248struct mesh_path *mesh_path_lookup(u8 *dst, 249 struct ieee80211_sub_if_data *sdata); 250struct mesh_path *mpp_path_lookup(u8 *dst, 251 struct ieee80211_sub_if_data *sdata); 252int mpp_path_add(u8 *dst, u8 *mpp, struct ieee80211_sub_if_data *sdata); 253struct mesh_path *mesh_path_lookup_by_idx(int idx, 254 struct ieee80211_sub_if_data *sdata); 255void mesh_path_fix_nexthop(struct mesh_path *mpath, struct sta_info *next_hop); 256void mesh_path_expire(struct ieee80211_sub_if_data *sdata); 257void mesh_path_flush(struct ieee80211_sub_if_data *sdata); 258void mesh_rx_path_sel_frame(struct ieee80211_sub_if_data *sdata, 259 struct ieee80211_mgmt *mgmt, size_t len); 260int mesh_path_add(u8 *dst, struct ieee80211_sub_if_data *sdata); 261/* Mesh plinks */ 262void mesh_neighbour_update(u8 *hw_addr, u32 rates, 263 struct ieee80211_sub_if_data *sdata, bool add); 264bool mesh_peer_accepts_plinks(struct ieee802_11_elems *ie); 265void mesh_accept_plinks_update(struct ieee80211_sub_if_data *sdata); 266void mesh_plink_broken(struct sta_info *sta); 267void mesh_plink_deactivate(struct sta_info *sta); 268int mesh_plink_open(struct sta_info *sta); 269void mesh_plink_block(struct sta_info *sta); 270void 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 */ 276struct mesh_table *mesh_table_alloc(int size_order); 277void mesh_table_free(struct mesh_table *tbl, bool free_leafs); 278void mesh_mpath_table_grow(void); 279void mesh_mpp_table_grow(void); 280u32 mesh_table_hash(u8 *addr, struct ieee80211_sub_if_data *sdata, 281 struct mesh_table *tbl); 282/* Mesh paths */ 283int mesh_path_error_tx(u8 ttl, u8 *target, __le32 target_sn, __le16 target_rcode, 284 const u8 *ra, struct ieee80211_sub_if_data *sdata); 285void mesh_path_assign_nexthop(struct mesh_path *mpath, struct sta_info *sta); 286void mesh_path_flush_pending(struct mesh_path *mpath); 287void mesh_path_tx_pending(struct mesh_path *mpath); 288int mesh_pathtbl_init(void); 289void mesh_pathtbl_unregister(void); 290int mesh_path_del(u8 *addr, struct ieee80211_sub_if_data *sdata); 291void mesh_path_timer(unsigned long data); 292void mesh_path_flush_by_nexthop(struct sta_info *sta); 293void mesh_path_discard_frame(struct sk_buff *skb, 294 struct ieee80211_sub_if_data *sdata); 295void mesh_path_quiesce(struct ieee80211_sub_if_data *sdata); 296void mesh_path_restart(struct ieee80211_sub_if_data *sdata); 297void mesh_path_tx_root_frame(struct ieee80211_sub_if_data *sdata); 298 299extern int mesh_paths_generation; 300 301#ifdef CONFIG_MAC80211_MESH 302extern int mesh_allocated; 303 304static 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 310static 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 316static 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 325void ieee80211_mesh_notify_scan_completed(struct ieee80211_local *local); 326 327void ieee80211_mesh_quiesce(struct ieee80211_sub_if_data *sdata); 328void ieee80211_mesh_restart(struct ieee80211_sub_if_data *sdata); 329void mesh_plink_quiesce(struct sta_info *sta); 330void mesh_plink_restart(struct sta_info *sta); 331#else 332#define mesh_allocated 0 333static inline void 334ieee80211_mesh_notify_scan_completed(struct ieee80211_local *local) {} 335static inline void ieee80211_mesh_quiesce(struct ieee80211_sub_if_data *sdata) 336{} 337static inline void ieee80211_mesh_restart(struct ieee80211_sub_if_data *sdata) 338{} 339static inline void mesh_plink_quiesce(struct sta_info *sta) {} 340static inline void mesh_plink_restart(struct sta_info *sta) {} 341#endif 342 343#endif /* IEEE80211S_H */ 344