xref: /linux/net/mac80211/mesh.h (revision a5d9265e017f081f0dc133c0e2f45103d027b874)
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  * @MESH_PATH_ACTIVE: the mesh path can be used for forwarding
25  * @MESH_PATH_RESOLVING: the discovery process is running for this mesh path
26  * @MESH_PATH_SN_VALID: the mesh path contains a valid destination sequence
27  *	number
28  * @MESH_PATH_FIXED: the mesh path has been manually set and should not be
29  *	modified
30  * @MESH_PATH_RESOLVED: the mesh path can has been resolved
31  * @MESH_PATH_REQ_QUEUED: there is an unsent path request for this destination
32  *	already queued up, waiting for the discovery process to start.
33  * @MESH_PATH_DELETED: the mesh path has been deleted and should no longer
34  *	be used
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 	MESH_PATH_DELETED =	BIT(6),
47 };
48 
49 /**
50  * enum mesh_deferred_task_flags - mac80211 mesh deferred tasks
51  *
52  *
53  *
54  * @MESH_WORK_HOUSEKEEPING: run the periodic mesh housekeeping tasks
55  * @MESH_WORK_ROOT: the mesh root station needs to send a frame
56  * @MESH_WORK_DRIFT_ADJUST: time to compensate for clock drift relative to other
57  * mesh nodes
58  * @MESH_WORK_MBSS_CHANGED: rebuild beacon and notify driver of BSS changes
59  */
60 enum mesh_deferred_task_flags {
61 	MESH_WORK_HOUSEKEEPING,
62 	MESH_WORK_ROOT,
63 	MESH_WORK_DRIFT_ADJUST,
64 	MESH_WORK_MBSS_CHANGED,
65 };
66 
67 /**
68  * struct mesh_path - mac80211 mesh path structure
69  *
70  * @dst: mesh path destination mac address
71  * @mpp: mesh proxy mac address
72  * @rhash: rhashtable list pointer
73  * @gate_list: list pointer for known gates list
74  * @sdata: mesh subif
75  * @next_hop: mesh neighbor to which frames for this destination will be
76  *	forwarded
77  * @timer: mesh path discovery timer
78  * @frame_queue: pending queue for frames sent to this destination while the
79  *	path is unresolved
80  * @rcu: rcu head for freeing mesh path
81  * @sn: target sequence number
82  * @metric: current metric to this destination
83  * @hop_count: hops to destination
84  * @exp_time: in jiffies, when the path will expire or when it expired
85  * @discovery_timeout: timeout (lapse in jiffies) used for the last discovery
86  *	retry
87  * @discovery_retries: number of discovery retries
88  * @flags: mesh path flags, as specified on &enum mesh_path_flags
89  * @state_lock: mesh path state lock used to protect changes to the
90  * mpath itself.  No need to take this lock when adding or removing
91  * an mpath to a hash bucket on a path table.
92  * @rann_snd_addr: the RANN sender address
93  * @rann_metric: the aggregated path metric towards the root node
94  * @last_preq_to_root: Timestamp of last PREQ sent to root
95  * @is_root: the destination station of this path is a root node
96  * @is_gate: the destination station of this path is a mesh gate
97  * @path_change_count: the number of path changes to destination
98  *
99  *
100  * The dst address is unique in the mesh path table. Since the mesh_path is
101  * protected by RCU, deleting the next_hop STA must remove / substitute the
102  * mesh_path structure and wait until that is no longer reachable before
103  * destroying the STA completely.
104  */
105 struct mesh_path {
106 	u8 dst[ETH_ALEN];
107 	u8 mpp[ETH_ALEN];	/* used for MPP or MAP */
108 	struct rhash_head rhash;
109 	struct hlist_node gate_list;
110 	struct ieee80211_sub_if_data *sdata;
111 	struct sta_info __rcu *next_hop;
112 	struct timer_list timer;
113 	struct sk_buff_head frame_queue;
114 	struct rcu_head rcu;
115 	u32 sn;
116 	u32 metric;
117 	u8 hop_count;
118 	unsigned long exp_time;
119 	u32 discovery_timeout;
120 	u8 discovery_retries;
121 	enum mesh_path_flags flags;
122 	spinlock_t state_lock;
123 	u8 rann_snd_addr[ETH_ALEN];
124 	u32 rann_metric;
125 	unsigned long last_preq_to_root;
126 	bool is_root;
127 	bool is_gate;
128 	u32 path_change_count;
129 };
130 
131 /**
132  * struct mesh_table
133  *
134  * @known_gates: list of known mesh gates and their mpaths by the station. The
135  * gate's mpath may or may not be resolved and active.
136  * @gates_lock: protects updates to known_gates
137  * @rhead: the rhashtable containing struct mesh_paths, keyed by dest addr
138  * @entries: number of entries in the table
139  */
140 struct mesh_table {
141 	struct hlist_head known_gates;
142 	spinlock_t gates_lock;
143 	struct rhashtable rhead;
144 	atomic_t entries;		/* Up to MAX_MESH_NEIGHBOURS */
145 };
146 
147 /* Recent multicast cache */
148 /* RMC_BUCKETS must be a power of 2, maximum 256 */
149 #define RMC_BUCKETS		256
150 #define RMC_QUEUE_MAX_LEN	4
151 #define RMC_TIMEOUT		(3 * HZ)
152 
153 /**
154  * struct rmc_entry - entry in the Recent Multicast Cache
155  *
156  * @seqnum: mesh sequence number of the frame
157  * @exp_time: expiration time of the entry, in jiffies
158  * @sa: source address of the frame
159  * @list: hashtable list pointer
160  *
161  * The Recent Multicast Cache keeps track of the latest multicast frames that
162  * have been received by a mesh interface and discards received multicast frames
163  * that are found in the cache.
164  */
165 struct rmc_entry {
166 	struct hlist_node list;
167 	unsigned long exp_time;
168 	u32 seqnum;
169 	u8 sa[ETH_ALEN];
170 };
171 
172 struct mesh_rmc {
173 	struct hlist_head bucket[RMC_BUCKETS];
174 	u32 idx_mask;
175 };
176 
177 #define IEEE80211_MESH_HOUSEKEEPING_INTERVAL (60 * HZ)
178 
179 #define MESH_PATH_EXPIRE (600 * HZ)
180 
181 /* Default maximum number of plinks per interface */
182 #define MESH_MAX_PLINKS		256
183 
184 /* Maximum number of paths per interface */
185 #define MESH_MAX_MPATHS		1024
186 
187 /* Number of frames buffered per destination for unresolved destinations */
188 #define MESH_FRAME_QUEUE_LEN	10
189 
190 /* Public interfaces */
191 /* Various */
192 int ieee80211_fill_mesh_addresses(struct ieee80211_hdr *hdr, __le16 *fc,
193 				  const u8 *da, const u8 *sa);
194 unsigned int ieee80211_new_mesh_header(struct ieee80211_sub_if_data *sdata,
195 				       struct ieee80211s_hdr *meshhdr,
196 				       const char *addr4or5, const char *addr6);
197 int mesh_rmc_check(struct ieee80211_sub_if_data *sdata,
198 		   const u8 *addr, struct ieee80211s_hdr *mesh_hdr);
199 bool mesh_matches_local(struct ieee80211_sub_if_data *sdata,
200 			struct ieee802_11_elems *ie);
201 void mesh_ids_set_default(struct ieee80211_if_mesh *mesh);
202 int mesh_add_meshconf_ie(struct ieee80211_sub_if_data *sdata,
203 			 struct sk_buff *skb);
204 int mesh_add_meshid_ie(struct ieee80211_sub_if_data *sdata,
205 		       struct sk_buff *skb);
206 int mesh_add_rsn_ie(struct ieee80211_sub_if_data *sdata,
207 		    struct sk_buff *skb);
208 int mesh_add_vendor_ies(struct ieee80211_sub_if_data *sdata,
209 			struct sk_buff *skb);
210 int mesh_add_ht_cap_ie(struct ieee80211_sub_if_data *sdata,
211 		       struct sk_buff *skb);
212 int mesh_add_ht_oper_ie(struct ieee80211_sub_if_data *sdata,
213 			struct sk_buff *skb);
214 int mesh_add_vht_cap_ie(struct ieee80211_sub_if_data *sdata,
215 			struct sk_buff *skb);
216 int mesh_add_vht_oper_ie(struct ieee80211_sub_if_data *sdata,
217 			 struct sk_buff *skb);
218 void mesh_rmc_free(struct ieee80211_sub_if_data *sdata);
219 int mesh_rmc_init(struct ieee80211_sub_if_data *sdata);
220 void ieee80211s_init(void);
221 void ieee80211s_update_metric(struct ieee80211_local *local,
222 			      struct sta_info *sta,
223 			      struct ieee80211_tx_status *st);
224 void ieee80211_mesh_init_sdata(struct ieee80211_sub_if_data *sdata);
225 void ieee80211_mesh_teardown_sdata(struct ieee80211_sub_if_data *sdata);
226 int ieee80211_start_mesh(struct ieee80211_sub_if_data *sdata);
227 void ieee80211_stop_mesh(struct ieee80211_sub_if_data *sdata);
228 void ieee80211_mesh_root_setup(struct ieee80211_if_mesh *ifmsh);
229 const struct ieee80211_mesh_sync_ops *ieee80211_mesh_sync_ops_get(u8 method);
230 /* wrapper for ieee80211_bss_info_change_notify() */
231 void ieee80211_mbss_info_change_notify(struct ieee80211_sub_if_data *sdata,
232 				       u32 changed);
233 
234 /* mesh power save */
235 u32 ieee80211_mps_local_status_update(struct ieee80211_sub_if_data *sdata);
236 u32 ieee80211_mps_set_sta_local_pm(struct sta_info *sta,
237 				   enum nl80211_mesh_power_mode pm);
238 void ieee80211_mps_set_frame_flags(struct ieee80211_sub_if_data *sdata,
239 				   struct sta_info *sta,
240 				   struct ieee80211_hdr *hdr);
241 void ieee80211_mps_sta_status_update(struct sta_info *sta);
242 void ieee80211_mps_rx_h_sta_process(struct sta_info *sta,
243 				    struct ieee80211_hdr *hdr);
244 void ieee80211_mpsp_trigger_process(u8 *qc, struct sta_info *sta,
245 				    bool tx, bool acked);
246 void ieee80211_mps_frame_release(struct sta_info *sta,
247 				 struct ieee802_11_elems *elems);
248 
249 /* Mesh paths */
250 int mesh_nexthop_lookup(struct ieee80211_sub_if_data *sdata,
251 			struct sk_buff *skb);
252 int mesh_nexthop_resolve(struct ieee80211_sub_if_data *sdata,
253 			 struct sk_buff *skb);
254 void mesh_path_start_discovery(struct ieee80211_sub_if_data *sdata);
255 struct mesh_path *mesh_path_lookup(struct ieee80211_sub_if_data *sdata,
256 				   const u8 *dst);
257 struct mesh_path *mpp_path_lookup(struct ieee80211_sub_if_data *sdata,
258 				  const u8 *dst);
259 int mpp_path_add(struct ieee80211_sub_if_data *sdata,
260 		 const u8 *dst, const u8 *mpp);
261 struct mesh_path *
262 mesh_path_lookup_by_idx(struct ieee80211_sub_if_data *sdata, int idx);
263 struct mesh_path *
264 mpp_path_lookup_by_idx(struct ieee80211_sub_if_data *sdata, int idx);
265 void mesh_path_fix_nexthop(struct mesh_path *mpath, struct sta_info *next_hop);
266 void mesh_path_expire(struct ieee80211_sub_if_data *sdata);
267 void mesh_rx_path_sel_frame(struct ieee80211_sub_if_data *sdata,
268 			    struct ieee80211_mgmt *mgmt, size_t len);
269 struct mesh_path *
270 mesh_path_add(struct ieee80211_sub_if_data *sdata, const u8 *dst);
271 
272 int mesh_path_add_gate(struct mesh_path *mpath);
273 int mesh_path_send_to_gates(struct mesh_path *mpath);
274 int mesh_gate_num(struct ieee80211_sub_if_data *sdata);
275 
276 /* Mesh plinks */
277 void mesh_neighbour_update(struct ieee80211_sub_if_data *sdata,
278 			   u8 *hw_addr, struct ieee802_11_elems *ie,
279 			   struct ieee80211_rx_status *rx_status);
280 bool mesh_peer_accepts_plinks(struct ieee802_11_elems *ie);
281 u32 mesh_accept_plinks_update(struct ieee80211_sub_if_data *sdata);
282 void mesh_plink_timer(struct timer_list *t);
283 void mesh_plink_broken(struct sta_info *sta);
284 u32 mesh_plink_deactivate(struct sta_info *sta);
285 u32 mesh_plink_open(struct sta_info *sta);
286 u32 mesh_plink_block(struct sta_info *sta);
287 void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata,
288 			 struct ieee80211_mgmt *mgmt, size_t len,
289 			 struct ieee80211_rx_status *rx_status);
290 void mesh_sta_cleanup(struct sta_info *sta);
291 
292 /* Private interfaces */
293 /* Mesh paths */
294 int mesh_path_error_tx(struct ieee80211_sub_if_data *sdata,
295 		       u8 ttl, const u8 *target, u32 target_sn,
296 		       u16 target_rcode, const u8 *ra);
297 void mesh_path_assign_nexthop(struct mesh_path *mpath, struct sta_info *sta);
298 void mesh_path_flush_pending(struct mesh_path *mpath);
299 void mesh_path_tx_pending(struct mesh_path *mpath);
300 int mesh_pathtbl_init(struct ieee80211_sub_if_data *sdata);
301 void mesh_pathtbl_unregister(struct ieee80211_sub_if_data *sdata);
302 int mesh_path_del(struct ieee80211_sub_if_data *sdata, const u8 *addr);
303 void mesh_path_timer(struct timer_list *t);
304 void mesh_path_flush_by_nexthop(struct sta_info *sta);
305 void mesh_path_discard_frame(struct ieee80211_sub_if_data *sdata,
306 			     struct sk_buff *skb);
307 void mesh_path_tx_root_frame(struct ieee80211_sub_if_data *sdata);
308 
309 bool mesh_action_is_path_sel(struct ieee80211_mgmt *mgmt);
310 
311 #ifdef CONFIG_MAC80211_MESH
312 static inline
313 u32 mesh_plink_inc_estab_count(struct ieee80211_sub_if_data *sdata)
314 {
315 	atomic_inc(&sdata->u.mesh.estab_plinks);
316 	return mesh_accept_plinks_update(sdata) | BSS_CHANGED_BEACON;
317 }
318 
319 static inline
320 u32 mesh_plink_dec_estab_count(struct ieee80211_sub_if_data *sdata)
321 {
322 	atomic_dec(&sdata->u.mesh.estab_plinks);
323 	return mesh_accept_plinks_update(sdata) | BSS_CHANGED_BEACON;
324 }
325 
326 static inline int mesh_plink_free_count(struct ieee80211_sub_if_data *sdata)
327 {
328 	return sdata->u.mesh.mshcfg.dot11MeshMaxPeerLinks -
329 	       atomic_read(&sdata->u.mesh.estab_plinks);
330 }
331 
332 static inline bool mesh_plink_availables(struct ieee80211_sub_if_data *sdata)
333 {
334 	return (min_t(long, mesh_plink_free_count(sdata),
335 		   MESH_MAX_PLINKS - sdata->local->num_sta)) > 0;
336 }
337 
338 static inline void mesh_path_activate(struct mesh_path *mpath)
339 {
340 	mpath->flags |= MESH_PATH_ACTIVE | MESH_PATH_RESOLVED;
341 }
342 
343 static inline bool mesh_path_sel_is_hwmp(struct ieee80211_sub_if_data *sdata)
344 {
345 	return sdata->u.mesh.mesh_pp_id == IEEE80211_PATH_PROTOCOL_HWMP;
346 }
347 
348 void mesh_path_flush_by_iface(struct ieee80211_sub_if_data *sdata);
349 void mesh_sync_adjust_tsf(struct ieee80211_sub_if_data *sdata);
350 void ieee80211s_stop(void);
351 #else
352 static inline bool mesh_path_sel_is_hwmp(struct ieee80211_sub_if_data *sdata)
353 { return false; }
354 static inline void mesh_path_flush_by_iface(struct ieee80211_sub_if_data *sdata)
355 {}
356 static inline void ieee80211s_stop(void) {}
357 #endif
358 
359 #endif /* IEEE80211S_H */
360