xref: /openbmc/linux/net/mac80211/mesh.h (revision f9a82c48)
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  * @walk_list: linked list containing all mesh_path objects.
74  * @gate_list: list pointer for known gates list
75  * @sdata: mesh subif
76  * @next_hop: mesh neighbor to which frames for this destination will be
77  *	forwarded
78  * @timer: mesh path discovery timer
79  * @frame_queue: pending queue for frames sent to this destination while the
80  *	path is unresolved
81  * @rcu: rcu head for freeing mesh path
82  * @sn: target sequence number
83  * @metric: current metric to this destination
84  * @hop_count: hops to destination
85  * @exp_time: in jiffies, when the path will expire or when it expired
86  * @discovery_timeout: timeout (lapse in jiffies) used for the last discovery
87  *	retry
88  * @discovery_retries: number of discovery retries
89  * @flags: mesh path flags, as specified on &enum mesh_path_flags
90  * @state_lock: mesh path state lock used to protect changes to the
91  * mpath itself.  No need to take this lock when adding or removing
92  * an mpath to a hash bucket on a path table.
93  * @rann_snd_addr: the RANN sender address
94  * @rann_metric: the aggregated path metric towards the root node
95  * @last_preq_to_root: Timestamp of last PREQ sent to root
96  * @is_root: the destination station of this path is a root node
97  * @is_gate: the destination station of this path is a mesh gate
98  * @path_change_count: the number of path changes to destination
99  *
100  *
101  * The dst address is unique in the mesh path table. Since the mesh_path is
102  * protected by RCU, deleting the next_hop STA must remove / substitute the
103  * mesh_path structure and wait until that is no longer reachable before
104  * destroying the STA completely.
105  */
106 struct mesh_path {
107 	u8 dst[ETH_ALEN];
108 	u8 mpp[ETH_ALEN];	/* used for MPP or MAP */
109 	struct rhash_head rhash;
110 	struct hlist_node walk_list;
111 	struct hlist_node gate_list;
112 	struct ieee80211_sub_if_data *sdata;
113 	struct sta_info __rcu *next_hop;
114 	struct timer_list timer;
115 	struct sk_buff_head frame_queue;
116 	struct rcu_head rcu;
117 	u32 sn;
118 	u32 metric;
119 	u8 hop_count;
120 	unsigned long exp_time;
121 	u32 discovery_timeout;
122 	u8 discovery_retries;
123 	enum mesh_path_flags flags;
124 	spinlock_t state_lock;
125 	u8 rann_snd_addr[ETH_ALEN];
126 	u32 rann_metric;
127 	unsigned long last_preq_to_root;
128 	bool is_root;
129 	bool is_gate;
130 	u32 path_change_count;
131 };
132 
133 /**
134  * struct mesh_table
135  *
136  * @known_gates: list of known mesh gates and their mpaths by the station. The
137  * gate's mpath may or may not be resolved and active.
138  * @gates_lock: protects updates to known_gates
139  * @rhead: the rhashtable containing struct mesh_paths, keyed by dest addr
140  * @walk_head: linked list containging all mesh_path objects
141  * @walk_lock: lock protecting walk_head
142  * @entries: number of entries in the table
143  */
144 struct mesh_table {
145 	struct hlist_head known_gates;
146 	spinlock_t gates_lock;
147 	struct rhashtable rhead;
148 	struct hlist_head walk_head;
149 	spinlock_t walk_lock;
150 	atomic_t entries;		/* Up to MAX_MESH_NEIGHBOURS */
151 };
152 
153 /* Recent multicast cache */
154 /* RMC_BUCKETS must be a power of 2, maximum 256 */
155 #define RMC_BUCKETS		256
156 #define RMC_QUEUE_MAX_LEN	4
157 #define RMC_TIMEOUT		(3 * HZ)
158 
159 /**
160  * struct rmc_entry - entry in the Recent Multicast Cache
161  *
162  * @seqnum: mesh sequence number of the frame
163  * @exp_time: expiration time of the entry, in jiffies
164  * @sa: source address of the frame
165  * @list: hashtable list pointer
166  *
167  * The Recent Multicast Cache keeps track of the latest multicast frames that
168  * have been received by a mesh interface and discards received multicast frames
169  * that are found in the cache.
170  */
171 struct rmc_entry {
172 	struct hlist_node list;
173 	unsigned long exp_time;
174 	u32 seqnum;
175 	u8 sa[ETH_ALEN];
176 };
177 
178 struct mesh_rmc {
179 	struct hlist_head bucket[RMC_BUCKETS];
180 	u32 idx_mask;
181 };
182 
183 #define IEEE80211_MESH_HOUSEKEEPING_INTERVAL (60 * HZ)
184 
185 #define MESH_PATH_EXPIRE (600 * HZ)
186 
187 /* Default maximum number of plinks per interface */
188 #define MESH_MAX_PLINKS		256
189 
190 /* Maximum number of paths per interface */
191 #define MESH_MAX_MPATHS		1024
192 
193 /* Number of frames buffered per destination for unresolved destinations */
194 #define MESH_FRAME_QUEUE_LEN	10
195 
196 /* Public interfaces */
197 /* Various */
198 int ieee80211_fill_mesh_addresses(struct ieee80211_hdr *hdr, __le16 *fc,
199 				  const u8 *da, const u8 *sa);
200 unsigned int ieee80211_new_mesh_header(struct ieee80211_sub_if_data *sdata,
201 				       struct ieee80211s_hdr *meshhdr,
202 				       const char *addr4or5, const char *addr6);
203 int mesh_rmc_check(struct ieee80211_sub_if_data *sdata,
204 		   const u8 *addr, struct ieee80211s_hdr *mesh_hdr);
205 bool mesh_matches_local(struct ieee80211_sub_if_data *sdata,
206 			struct ieee802_11_elems *ie);
207 void mesh_ids_set_default(struct ieee80211_if_mesh *mesh);
208 int mesh_add_meshconf_ie(struct ieee80211_sub_if_data *sdata,
209 			 struct sk_buff *skb);
210 int mesh_add_meshid_ie(struct ieee80211_sub_if_data *sdata,
211 		       struct sk_buff *skb);
212 int mesh_add_rsn_ie(struct ieee80211_sub_if_data *sdata,
213 		    struct sk_buff *skb);
214 int mesh_add_vendor_ies(struct ieee80211_sub_if_data *sdata,
215 			struct sk_buff *skb);
216 int mesh_add_ht_cap_ie(struct ieee80211_sub_if_data *sdata,
217 		       struct sk_buff *skb);
218 int mesh_add_ht_oper_ie(struct ieee80211_sub_if_data *sdata,
219 			struct sk_buff *skb);
220 int mesh_add_vht_cap_ie(struct ieee80211_sub_if_data *sdata,
221 			struct sk_buff *skb);
222 int mesh_add_vht_oper_ie(struct ieee80211_sub_if_data *sdata,
223 			 struct sk_buff *skb);
224 void mesh_rmc_free(struct ieee80211_sub_if_data *sdata);
225 int mesh_rmc_init(struct ieee80211_sub_if_data *sdata);
226 void ieee80211s_init(void);
227 void ieee80211s_update_metric(struct ieee80211_local *local,
228 			      struct sta_info *sta,
229 			      struct ieee80211_tx_status *st);
230 void ieee80211_mesh_init_sdata(struct ieee80211_sub_if_data *sdata);
231 void ieee80211_mesh_teardown_sdata(struct ieee80211_sub_if_data *sdata);
232 int 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 const struct ieee80211_mesh_sync_ops *ieee80211_mesh_sync_ops_get(u8 method);
236 /* wrapper for ieee80211_bss_info_change_notify() */
237 void ieee80211_mbss_info_change_notify(struct ieee80211_sub_if_data *sdata,
238 				       u32 changed);
239 
240 /* mesh power save */
241 u32 ieee80211_mps_local_status_update(struct ieee80211_sub_if_data *sdata);
242 u32 ieee80211_mps_set_sta_local_pm(struct sta_info *sta,
243 				   enum nl80211_mesh_power_mode pm);
244 void ieee80211_mps_set_frame_flags(struct ieee80211_sub_if_data *sdata,
245 				   struct sta_info *sta,
246 				   struct ieee80211_hdr *hdr);
247 void ieee80211_mps_sta_status_update(struct sta_info *sta);
248 void ieee80211_mps_rx_h_sta_process(struct sta_info *sta,
249 				    struct ieee80211_hdr *hdr);
250 void ieee80211_mpsp_trigger_process(u8 *qc, struct sta_info *sta,
251 				    bool tx, bool acked);
252 void ieee80211_mps_frame_release(struct sta_info *sta,
253 				 struct ieee802_11_elems *elems);
254 
255 /* Mesh paths */
256 int mesh_nexthop_lookup(struct ieee80211_sub_if_data *sdata,
257 			struct sk_buff *skb);
258 int mesh_nexthop_resolve(struct ieee80211_sub_if_data *sdata,
259 			 struct sk_buff *skb);
260 void mesh_path_start_discovery(struct ieee80211_sub_if_data *sdata);
261 struct mesh_path *mesh_path_lookup(struct ieee80211_sub_if_data *sdata,
262 				   const u8 *dst);
263 struct mesh_path *mpp_path_lookup(struct ieee80211_sub_if_data *sdata,
264 				  const u8 *dst);
265 int mpp_path_add(struct ieee80211_sub_if_data *sdata,
266 		 const u8 *dst, const u8 *mpp);
267 struct mesh_path *
268 mesh_path_lookup_by_idx(struct ieee80211_sub_if_data *sdata, int idx);
269 struct mesh_path *
270 mpp_path_lookup_by_idx(struct ieee80211_sub_if_data *sdata, int idx);
271 void mesh_path_fix_nexthop(struct mesh_path *mpath, struct sta_info *next_hop);
272 void mesh_path_expire(struct ieee80211_sub_if_data *sdata);
273 void mesh_rx_path_sel_frame(struct ieee80211_sub_if_data *sdata,
274 			    struct ieee80211_mgmt *mgmt, size_t len);
275 struct mesh_path *
276 mesh_path_add(struct ieee80211_sub_if_data *sdata, const u8 *dst);
277 
278 int mesh_path_add_gate(struct mesh_path *mpath);
279 int mesh_path_send_to_gates(struct mesh_path *mpath);
280 int mesh_gate_num(struct ieee80211_sub_if_data *sdata);
281 
282 /* Mesh plinks */
283 void mesh_neighbour_update(struct ieee80211_sub_if_data *sdata,
284 			   u8 *hw_addr, struct ieee802_11_elems *ie,
285 			   struct ieee80211_rx_status *rx_status);
286 bool mesh_peer_accepts_plinks(struct ieee802_11_elems *ie);
287 u32 mesh_accept_plinks_update(struct ieee80211_sub_if_data *sdata);
288 void mesh_plink_timer(struct timer_list *t);
289 void mesh_plink_broken(struct sta_info *sta);
290 u32 mesh_plink_deactivate(struct sta_info *sta);
291 u32 mesh_plink_open(struct sta_info *sta);
292 u32 mesh_plink_block(struct sta_info *sta);
293 void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata,
294 			 struct ieee80211_mgmt *mgmt, size_t len,
295 			 struct ieee80211_rx_status *rx_status);
296 void mesh_sta_cleanup(struct sta_info *sta);
297 
298 /* Private interfaces */
299 /* Mesh paths */
300 int mesh_path_error_tx(struct ieee80211_sub_if_data *sdata,
301 		       u8 ttl, const u8 *target, u32 target_sn,
302 		       u16 target_rcode, const u8 *ra);
303 void mesh_path_assign_nexthop(struct mesh_path *mpath, struct sta_info *sta);
304 void mesh_path_flush_pending(struct mesh_path *mpath);
305 void mesh_path_tx_pending(struct mesh_path *mpath);
306 int mesh_pathtbl_init(struct ieee80211_sub_if_data *sdata);
307 void mesh_pathtbl_unregister(struct ieee80211_sub_if_data *sdata);
308 int mesh_path_del(struct ieee80211_sub_if_data *sdata, const u8 *addr);
309 void mesh_path_timer(struct timer_list *t);
310 void mesh_path_flush_by_nexthop(struct sta_info *sta);
311 void mesh_path_discard_frame(struct ieee80211_sub_if_data *sdata,
312 			     struct sk_buff *skb);
313 void mesh_path_tx_root_frame(struct ieee80211_sub_if_data *sdata);
314 
315 bool mesh_action_is_path_sel(struct ieee80211_mgmt *mgmt);
316 
317 #ifdef CONFIG_MAC80211_MESH
318 static inline
319 u32 mesh_plink_inc_estab_count(struct ieee80211_sub_if_data *sdata)
320 {
321 	atomic_inc(&sdata->u.mesh.estab_plinks);
322 	return mesh_accept_plinks_update(sdata) | BSS_CHANGED_BEACON;
323 }
324 
325 static inline
326 u32 mesh_plink_dec_estab_count(struct ieee80211_sub_if_data *sdata)
327 {
328 	atomic_dec(&sdata->u.mesh.estab_plinks);
329 	return mesh_accept_plinks_update(sdata) | BSS_CHANGED_BEACON;
330 }
331 
332 static inline int mesh_plink_free_count(struct ieee80211_sub_if_data *sdata)
333 {
334 	return sdata->u.mesh.mshcfg.dot11MeshMaxPeerLinks -
335 	       atomic_read(&sdata->u.mesh.estab_plinks);
336 }
337 
338 static inline bool mesh_plink_availables(struct ieee80211_sub_if_data *sdata)
339 {
340 	return (min_t(long, mesh_plink_free_count(sdata),
341 		   MESH_MAX_PLINKS - sdata->local->num_sta)) > 0;
342 }
343 
344 static inline void mesh_path_activate(struct mesh_path *mpath)
345 {
346 	mpath->flags |= MESH_PATH_ACTIVE | MESH_PATH_RESOLVED;
347 }
348 
349 static inline bool mesh_path_sel_is_hwmp(struct ieee80211_sub_if_data *sdata)
350 {
351 	return sdata->u.mesh.mesh_pp_id == IEEE80211_PATH_PROTOCOL_HWMP;
352 }
353 
354 void mesh_path_flush_by_iface(struct ieee80211_sub_if_data *sdata);
355 void mesh_sync_adjust_tsf(struct ieee80211_sub_if_data *sdata);
356 void ieee80211s_stop(void);
357 #else
358 static inline bool mesh_path_sel_is_hwmp(struct ieee80211_sub_if_data *sdata)
359 { return false; }
360 static inline void mesh_path_flush_by_iface(struct ieee80211_sub_if_data *sdata)
361 {}
362 static inline void ieee80211s_stop(void) {}
363 #endif
364 
365 #endif /* IEEE80211S_H */
366