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 "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 can be used for forwarding
27 * @MESH_PATH_RESOLVING: the discovery process is running for this mesh path
28 * @MESH_PATH_SN_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 * @MESH_PATH_REQ_QUEUED: there is an unsent path request for this destination
34 * already queued up, waiting for the discovery process to start.
35 *
36 * MESH_PATH_RESOLVED is used by the mesh path timer to
37 * decide when to stop or cancel the mesh path discovery.
38 */
39 enum mesh_path_flags {
40 MESH_PATH_ACTIVE = BIT(0),
41 MESH_PATH_RESOLVING = BIT(1),
42 MESH_PATH_SN_VALID = BIT(2),
43 MESH_PATH_FIXED = BIT(3),
44 MESH_PATH_RESOLVED = BIT(4),
45 MESH_PATH_REQ_QUEUED = BIT(5),
46 };
47
48 /**
49 * enum mesh_deferred_task_flags - mac80211 mesh deferred tasks
50 *
51 *
52 *
53 * @MESH_WORK_HOUSEKEEPING: run the periodic mesh housekeeping tasks
54 * @MESH_WORK_GROW_MPATH_TABLE: the mesh path table is full and needs
55 * to grow.
56 * @MESH_WORK_GROW_MPP_TABLE: the mesh portals table is full and needs to
57 * grow
58 * @MESH_WORK_ROOT: the mesh root station needs to send a frame
59 */
60 enum mesh_deferred_task_flags {
61 MESH_WORK_HOUSEKEEPING,
62 MESH_WORK_GROW_MPATH_TABLE,
63 MESH_WORK_GROW_MPP_TABLE,
64 MESH_WORK_ROOT,
65 };
66
67 /**
68 * struct mesh_path - mac80211 mesh path structure
69 *
70 * @dst: mesh path destination mac address
71 * @sdata: mesh subif
72 * @next_hop: mesh neighbor to which frames for this destination will be
73 * forwarded
74 * @timer: mesh path discovery timer
75 * @frame_queue: pending queue for frames sent to this destination while the
76 * path is unresolved
77 * @sn: target sequence number
78 * @metric: current metric to this destination
79 * @hop_count: hops to destination
80 * @exp_time: in jiffies, when the path will expire or when it expired
81 * @discovery_timeout: timeout (lapse in jiffies) used for the last discovery
82 * retry
83 * @discovery_retries: number of discovery retries
84 * @flags: mesh path flags, as specified on &enum mesh_path_flags
85 * @state_lock: mesh path state lock used to protect changes to the
86 * mpath itself. No need to take this lock when adding or removing
87 * an mpath to a hash bucket on a path table.
88 * @rann_snd_addr: the RANN sender address
89 * @is_root: the destination station of this path is a root node
90 * @is_gate: the destination station of this path is a mesh gate
91 *
92 *
93 * The combination of dst and sdata is unique in the mesh path table. Since the
94 * next_hop STA is only protected by RCU as well, deleting the STA must also
95 * remove/substitute the mesh_path structure and wait until that is no longer
96 * reachable before destroying the STA completely.
97 */
98 struct mesh_path {
99 u8 dst[ETH_ALEN];
100 u8 mpp[ETH_ALEN]; /* used for MPP or MAP */
101 struct ieee80211_sub_if_data *sdata;
102 struct sta_info __rcu *next_hop;
103 struct timer_list timer;
104 struct sk_buff_head frame_queue;
105 struct rcu_head rcu;
106 u32 sn;
107 u32 metric;
108 u8 hop_count;
109 unsigned long exp_time;
110 u32 discovery_timeout;
111 u8 discovery_retries;
112 enum mesh_path_flags flags;
113 spinlock_t state_lock;
114 u8 rann_snd_addr[ETH_ALEN];
115 bool is_root;
116 bool is_gate;
117 };
118
119 /**
120 * struct mesh_table
121 *
122 * @hash_buckets: array of hash buckets of the table
123 * @hashwlock: array of locks to protect write operations, one per bucket
124 * @hash_mask: 2^size_order - 1, used to compute hash idx
125 * @hash_rnd: random value used for hash computations
126 * @entries: number of entries in the table
127 * @free_node: function to free nodes of the table
128 * @copy_node: function to copy nodes of the table
129 * @size_order: determines size of the table, there will be 2^size_order hash
130 * buckets
131 * @mean_chain_len: maximum average length for the hash buckets' list, if it is
132 * reached, the table will grow
133 * @known_gates: list of known mesh gates and their mpaths by the station. The
134 * gate's mpath may or may not be resolved and active.
135 *
136 * rcu_head: RCU head to free the table
137 */
138 struct mesh_table {
139 /* Number of buckets will be 2^N */
140 struct hlist_head *hash_buckets;
141 spinlock_t *hashwlock; /* One per bucket, for add/del */
142 unsigned int hash_mask; /* (2^size_order) - 1 */
143 __u32 hash_rnd; /* Used for hash generation */
144 atomic_t entries; /* Up to MAX_MESH_NEIGHBOURS */
145 void (*free_node) (struct hlist_node *p, bool free_leafs);
146 int (*copy_node) (struct hlist_node *p, struct mesh_table *newtbl);
147 int size_order;
148 int mean_chain_len;
149 struct hlist_head *known_gates;
150 spinlock_t gates_lock;
151
152 struct rcu_head rcu_head;
153 };
154
155 /* Recent multicast cache */
156 /* RMC_BUCKETS must be a power of 2, maximum 256 */
157 #define RMC_BUCKETS 256
158 #define RMC_QUEUE_MAX_LEN 4
159 #define RMC_TIMEOUT (3 * HZ)
160
161 /**
162 * struct rmc_entry - entry in the Recent Multicast Cache
163 *
164 * @seqnum: mesh sequence number of the frame
165 * @exp_time: expiration time of the entry, in jiffies
166 * @sa: source address of the frame
167 *
168 * The Recent Multicast Cache keeps track of the latest multicast frames that
169 * have been received by a mesh interface and discards received multicast frames
170 * that are found in the cache.
171 */
172 struct rmc_entry {
173 struct list_head list;
174 u32 seqnum;
175 unsigned long exp_time;
176 u8 sa[ETH_ALEN];
177 };
178
179 struct mesh_rmc {
180 struct rmc_entry bucket[RMC_BUCKETS];
181 u32 idx_mask;
182 };
183
184 #define IEEE80211_MESH_PEER_INACTIVITY_LIMIT (1800 * HZ)
185 #define IEEE80211_MESH_HOUSEKEEPING_INTERVAL (60 * HZ)
186
187 #define MESH_DEFAULT_BEACON_INTERVAL 1000 /* in 1024 us units */
188
189 #define MESH_PATH_EXPIRE (600 * HZ)
190
191 /* Default maximum number of plinks per interface */
192 #define MESH_MAX_PLINKS 256
193
194 /* Maximum number of paths per interface */
195 #define MESH_MAX_MPATHS 1024
196
197 /* Public interfaces */
198 /* Various */
199 int ieee80211_fill_mesh_addresses(struct ieee80211_hdr *hdr, __le16 *fc,
200 const u8 *da, const u8 *sa);
201 int ieee80211_new_mesh_header(struct ieee80211s_hdr *meshhdr,
202 struct ieee80211_sub_if_data *sdata, char *addr4or5,
203 char *addr6);
204 int mesh_rmc_check(u8 *addr, struct ieee80211s_hdr *mesh_hdr,
205 struct ieee80211_sub_if_data *sdata);
206 bool mesh_matches_local(struct ieee802_11_elems *ie,
207 struct ieee80211_sub_if_data *sdata);
208 void mesh_ids_set_default(struct ieee80211_if_mesh *mesh);
209 void mesh_mgmt_ies_add(struct sk_buff *skb,
210 struct ieee80211_sub_if_data *sdata);
211 int mesh_add_meshconf_ie(struct sk_buff *skb,
212 struct ieee80211_sub_if_data *sdata);
213 int mesh_add_meshid_ie(struct sk_buff *skb,
214 struct ieee80211_sub_if_data *sdata);
215 int mesh_add_rsn_ie(struct sk_buff *skb,
216 struct ieee80211_sub_if_data *sdata);
217 int mesh_add_vendor_ies(struct sk_buff *skb,
218 struct ieee80211_sub_if_data *sdata);
219 int mesh_add_ds_params_ie(struct sk_buff *skb,
220 struct ieee80211_sub_if_data *sdata);
221 int mesh_add_ht_cap_ie(struct sk_buff *skb,
222 struct ieee80211_sub_if_data *sdata);
223 int mesh_add_ht_info_ie(struct sk_buff *skb,
224 struct ieee80211_sub_if_data *sdata);
225 void mesh_rmc_free(struct ieee80211_sub_if_data *sdata);
226 int mesh_rmc_init(struct ieee80211_sub_if_data *sdata);
227 void ieee80211s_init(void);
228 void ieee80211s_update_metric(struct ieee80211_local *local,
229 struct sta_info *stainfo, struct sk_buff *skb);
230 void ieee80211s_stop(void);
231 void ieee80211_mesh_init_sdata(struct ieee80211_sub_if_data *sdata);
232 void ieee80211_start_mesh(struct ieee80211_sub_if_data *sdata);
233 void ieee80211_stop_mesh(struct ieee80211_sub_if_data *sdata);
234 void ieee80211_mesh_root_setup(struct ieee80211_if_mesh *ifmsh);
235
236 /* Mesh paths */
237 int mesh_nexthop_lookup(struct sk_buff *skb,
238 struct ieee80211_sub_if_data *sdata);
239 int mesh_nexthop_resolve(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_rx_path_sel_frame(struct ieee80211_sub_if_data *sdata,
252 struct ieee80211_mgmt *mgmt, size_t len);
253 int mesh_path_add(u8 *dst, struct ieee80211_sub_if_data *sdata);
254
255 int mesh_path_add_gate(struct mesh_path *mpath);
256 int mesh_path_send_to_gates(struct mesh_path *mpath);
257 int mesh_gate_num(struct ieee80211_sub_if_data *sdata);
258 /* Mesh plinks */
259 void mesh_neighbour_update(u8 *hw_addr, u32 rates,
260 struct ieee80211_sub_if_data *sdata,
261 struct ieee802_11_elems *ie);
262 bool mesh_peer_accepts_plinks(struct ieee802_11_elems *ie);
263 void mesh_accept_plinks_update(struct ieee80211_sub_if_data *sdata);
264 void mesh_plink_broken(struct sta_info *sta);
265 void mesh_plink_deactivate(struct sta_info *sta);
266 int mesh_plink_open(struct sta_info *sta);
267 void mesh_plink_block(struct sta_info *sta);
268 void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata,
269 struct ieee80211_mgmt *mgmt, size_t len,
270 struct ieee80211_rx_status *rx_status);
271
272 /* Private interfaces */
273 /* Mesh tables */
274 void mesh_mpath_table_grow(void);
275 void mesh_mpp_table_grow(void);
276 /* Mesh paths */
277 int mesh_path_error_tx(u8 ttl, u8 *target, __le32 target_sn, __le16 target_rcode,
278 const u8 *ra, 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_flush_by_iface(struct ieee80211_sub_if_data *sdata);
288 void mesh_path_discard_frame(struct sk_buff *skb,
289 struct ieee80211_sub_if_data *sdata);
290 void mesh_path_quiesce(struct ieee80211_sub_if_data *sdata);
291 void mesh_path_restart(struct ieee80211_sub_if_data *sdata);
292 void mesh_path_tx_root_frame(struct ieee80211_sub_if_data *sdata);
293
294 bool mesh_action_is_path_sel(struct ieee80211_mgmt *mgmt);
295 extern int mesh_paths_generation;
296
297 #ifdef CONFIG_MAC80211_MESH
298 extern int mesh_allocated;
299
mesh_plink_free_count(struct ieee80211_sub_if_data * sdata)300 static inline int mesh_plink_free_count(struct ieee80211_sub_if_data *sdata)
301 {
302 return sdata->u.mesh.mshcfg.dot11MeshMaxPeerLinks -
303 atomic_read(&sdata->u.mesh.mshstats.estab_plinks);
304 }
305
mesh_plink_availables(struct ieee80211_sub_if_data * sdata)306 static inline bool mesh_plink_availables(struct ieee80211_sub_if_data *sdata)
307 {
308 return (min_t(long, mesh_plink_free_count(sdata),
309 MESH_MAX_PLINKS - sdata->local->num_sta)) > 0;
310 }
311
mesh_path_activate(struct mesh_path * mpath)312 static inline void mesh_path_activate(struct mesh_path *mpath)
313 {
314 mpath->flags |= MESH_PATH_ACTIVE | MESH_PATH_RESOLVED;
315 }
316
mesh_path_sel_is_hwmp(struct ieee80211_sub_if_data * sdata)317 static inline bool mesh_path_sel_is_hwmp(struct ieee80211_sub_if_data *sdata)
318 {
319 return sdata->u.mesh.mesh_pp_id == IEEE80211_PATH_PROTOCOL_HWMP;
320 }
321
322 void ieee80211_mesh_notify_scan_completed(struct ieee80211_local *local);
323
324 void ieee80211_mesh_quiesce(struct ieee80211_sub_if_data *sdata);
325 void ieee80211_mesh_restart(struct ieee80211_sub_if_data *sdata);
326 void mesh_plink_quiesce(struct sta_info *sta);
327 void mesh_plink_restart(struct sta_info *sta);
328 #else
329 #define mesh_allocated 0
330 static inline void
ieee80211_mesh_notify_scan_completed(struct ieee80211_local * local)331 ieee80211_mesh_notify_scan_completed(struct ieee80211_local *local) {}
ieee80211_mesh_quiesce(struct ieee80211_sub_if_data * sdata)332 static inline void ieee80211_mesh_quiesce(struct ieee80211_sub_if_data *sdata)
333 {}
ieee80211_mesh_restart(struct ieee80211_sub_if_data * sdata)334 static inline void ieee80211_mesh_restart(struct ieee80211_sub_if_data *sdata)
335 {}
mesh_plink_quiesce(struct sta_info * sta)336 static inline void mesh_plink_quiesce(struct sta_info *sta) {}
mesh_plink_restart(struct sta_info * sta)337 static inline void mesh_plink_restart(struct sta_info *sta) {}
mesh_path_sel_is_hwmp(struct ieee80211_sub_if_data * sdata)338 static inline bool mesh_path_sel_is_hwmp(struct ieee80211_sub_if_data *sdata)
339 { return false; }
340 #endif
341
342 #endif /* IEEE80211S_H */
343