xref: /linux/net/mac80211/mesh.h (revision 37744feebc086908fd89760650f458ab19071750)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Copyright (c) 2008, 2009 open80211s Ltd.
4  * Authors:    Luis Carlos Cobo <luisca@cozybit.com>
5  *             Javier Cardona <javier@cozybit.com>
6  */
7 
8 #ifndef IEEE80211S_H
9 #define IEEE80211S_H
10 
11 #include <linux/types.h>
12 #include <linux/jhash.h>
13 #include "ieee80211_i.h"
14 
15 
16 /* Data structures */
17 
18 /**
19  * enum mesh_path_flags - mac80211 mesh path flags
20  *
21  * @MESH_PATH_ACTIVE: the mesh path can be used for forwarding
22  * @MESH_PATH_RESOLVING: the discovery process is running for this mesh path
23  * @MESH_PATH_SN_VALID: the mesh path contains a valid destination sequence
24  *	number
25  * @MESH_PATH_FIXED: the mesh path has been manually set and should not be
26  *	modified
27  * @MESH_PATH_RESOLVED: the mesh path can has been resolved
28  * @MESH_PATH_REQ_QUEUED: there is an unsent path request for this destination
29  *	already queued up, waiting for the discovery process to start.
30  * @MESH_PATH_DELETED: the mesh path has been deleted and should no longer
31  *	be used
32  *
33  * MESH_PATH_RESOLVED is used by the mesh path timer to
34  * decide when to stop or cancel the mesh path discovery.
35  */
36 enum mesh_path_flags {
37 	MESH_PATH_ACTIVE =	BIT(0),
38 	MESH_PATH_RESOLVING =	BIT(1),
39 	MESH_PATH_SN_VALID =	BIT(2),
40 	MESH_PATH_FIXED	=	BIT(3),
41 	MESH_PATH_RESOLVED =	BIT(4),
42 	MESH_PATH_REQ_QUEUED =	BIT(5),
43 	MESH_PATH_DELETED =	BIT(6),
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_ROOT: the mesh root station needs to send a frame
53  * @MESH_WORK_DRIFT_ADJUST: time to compensate for clock drift relative to other
54  * mesh nodes
55  * @MESH_WORK_MBSS_CHANGED: rebuild beacon and notify driver of BSS changes
56  */
57 enum mesh_deferred_task_flags {
58 	MESH_WORK_HOUSEKEEPING,
59 	MESH_WORK_ROOT,
60 	MESH_WORK_DRIFT_ADJUST,
61 	MESH_WORK_MBSS_CHANGED,
62 };
63 
64 /**
65  * struct mesh_path - mac80211 mesh path structure
66  *
67  * @dst: mesh path destination mac address
68  * @mpp: mesh proxy mac address
69  * @rhash: rhashtable list pointer
70  * @walk_list: linked list containing all mesh_path objects.
71  * @gate_list: list pointer for known gates list
72  * @sdata: mesh subif
73  * @next_hop: mesh neighbor to which frames for this destination will be
74  *	forwarded
75  * @timer: mesh path discovery timer
76  * @frame_queue: pending queue for frames sent to this destination while the
77  *	path is unresolved
78  * @rcu: rcu head for freeing mesh path
79  * @sn: target sequence number
80  * @metric: current metric to this destination
81  * @hop_count: hops to destination
82  * @exp_time: in jiffies, when the path will expire or when it expired
83  * @discovery_timeout: timeout (lapse in jiffies) used for the last discovery
84  *	retry
85  * @discovery_retries: number of discovery retries
86  * @flags: mesh path flags, as specified on &enum mesh_path_flags
87  * @state_lock: mesh path state lock used to protect changes to the
88  * mpath itself.  No need to take this lock when adding or removing
89  * an mpath to a hash bucket on a path table.
90  * @rann_snd_addr: the RANN sender address
91  * @rann_metric: the aggregated path metric towards the root node
92  * @last_preq_to_root: Timestamp of last PREQ sent to root
93  * @is_root: the destination station of this path is a root node
94  * @is_gate: the destination station of this path is a mesh gate
95  * @path_change_count: the number of path changes to destination
96  *
97  *
98  * The dst address is unique in the mesh path table. Since the mesh_path is
99  * protected by RCU, deleting the next_hop STA must remove / substitute the
100  * mesh_path structure and wait until that is no longer reachable before
101  * destroying the STA completely.
102  */
103 struct mesh_path {
104 	u8 dst[ETH_ALEN];
105 	u8 mpp[ETH_ALEN];	/* used for MPP or MAP */
106 	struct rhash_head rhash;
107 	struct hlist_node walk_list;
108 	struct hlist_node gate_list;
109 	struct ieee80211_sub_if_data *sdata;
110 	struct sta_info __rcu *next_hop;
111 	struct timer_list timer;
112 	struct sk_buff_head frame_queue;
113 	struct rcu_head rcu;
114 	u32 sn;
115 	u32 metric;
116 	u8 hop_count;
117 	unsigned long exp_time;
118 	u32 discovery_timeout;
119 	u8 discovery_retries;
120 	enum mesh_path_flags flags;
121 	spinlock_t state_lock;
122 	u8 rann_snd_addr[ETH_ALEN];
123 	u32 rann_metric;
124 	unsigned long last_preq_to_root;
125 	bool is_root;
126 	bool is_gate;
127 	u32 path_change_count;
128 };
129 
130 /**
131  * struct mesh_table
132  *
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  * @gates_lock: protects updates to known_gates
136  * @rhead: the rhashtable containing struct mesh_paths, keyed by dest addr
137  * @walk_head: linked list containging all mesh_path objects
138  * @walk_lock: lock protecting walk_head
139  * @entries: number of entries in the table
140  */
141 struct mesh_table {
142 	struct hlist_head known_gates;
143 	spinlock_t gates_lock;
144 	struct rhashtable rhead;
145 	struct hlist_head walk_head;
146 	spinlock_t walk_lock;
147 	atomic_t entries;		/* Up to MAX_MESH_NEIGHBOURS */
148 };
149 
150 /* Recent multicast cache */
151 /* RMC_BUCKETS must be a power of 2, maximum 256 */
152 #define RMC_BUCKETS		256
153 #define RMC_QUEUE_MAX_LEN	4
154 #define RMC_TIMEOUT		(3 * HZ)
155 
156 /**
157  * struct rmc_entry - entry in the Recent Multicast Cache
158  *
159  * @seqnum: mesh sequence number of the frame
160  * @exp_time: expiration time of the entry, in jiffies
161  * @sa: source address of the frame
162  * @list: hashtable list pointer
163  *
164  * The Recent Multicast Cache keeps track of the latest multicast frames that
165  * have been received by a mesh interface and discards received multicast frames
166  * that are found in the cache.
167  */
168 struct rmc_entry {
169 	struct hlist_node list;
170 	unsigned long exp_time;
171 	u32 seqnum;
172 	u8 sa[ETH_ALEN];
173 };
174 
175 struct mesh_rmc {
176 	struct hlist_head bucket[RMC_BUCKETS];
177 	u32 idx_mask;
178 };
179 
180 #define IEEE80211_MESH_HOUSEKEEPING_INTERVAL (60 * HZ)
181 
182 #define MESH_PATH_EXPIRE (600 * HZ)
183 
184 /* Default maximum number of plinks per interface */
185 #define MESH_MAX_PLINKS		256
186 
187 /* Maximum number of paths per interface */
188 #define MESH_MAX_MPATHS		1024
189 
190 /* Number of frames buffered per destination for unresolved destinations */
191 #define MESH_FRAME_QUEUE_LEN	10
192 
193 /* Public interfaces */
194 /* Various */
195 int ieee80211_fill_mesh_addresses(struct ieee80211_hdr *hdr, __le16 *fc,
196 				  const u8 *da, const u8 *sa);
197 unsigned int ieee80211_new_mesh_header(struct ieee80211_sub_if_data *sdata,
198 				       struct ieee80211s_hdr *meshhdr,
199 				       const char *addr4or5, const char *addr6);
200 int mesh_rmc_check(struct ieee80211_sub_if_data *sdata,
201 		   const u8 *addr, struct ieee80211s_hdr *mesh_hdr);
202 bool mesh_matches_local(struct ieee80211_sub_if_data *sdata,
203 			struct ieee802_11_elems *ie);
204 void mesh_ids_set_default(struct ieee80211_if_mesh *mesh);
205 int mesh_add_meshconf_ie(struct ieee80211_sub_if_data *sdata,
206 			 struct sk_buff *skb);
207 int mesh_add_meshid_ie(struct ieee80211_sub_if_data *sdata,
208 		       struct sk_buff *skb);
209 int mesh_add_rsn_ie(struct ieee80211_sub_if_data *sdata,
210 		    struct sk_buff *skb);
211 int mesh_add_vendor_ies(struct ieee80211_sub_if_data *sdata,
212 			struct sk_buff *skb);
213 int mesh_add_ht_cap_ie(struct ieee80211_sub_if_data *sdata,
214 		       struct sk_buff *skb);
215 int mesh_add_ht_oper_ie(struct ieee80211_sub_if_data *sdata,
216 			struct sk_buff *skb);
217 int mesh_add_vht_cap_ie(struct ieee80211_sub_if_data *sdata,
218 			struct sk_buff *skb);
219 int mesh_add_vht_oper_ie(struct ieee80211_sub_if_data *sdata,
220 			 struct sk_buff *skb);
221 int mesh_add_he_cap_ie(struct ieee80211_sub_if_data *sdata,
222 		       struct sk_buff *skb, u8 ie_len);
223 int mesh_add_he_oper_ie(struct ieee80211_sub_if_data *sdata,
224 			struct sk_buff *skb);
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 *sta,
230 			      struct ieee80211_tx_status *st);
231 void ieee80211_mesh_init_sdata(struct ieee80211_sub_if_data *sdata);
232 void ieee80211_mesh_teardown_sdata(struct ieee80211_sub_if_data *sdata);
233 int ieee80211_start_mesh(struct ieee80211_sub_if_data *sdata);
234 void ieee80211_stop_mesh(struct ieee80211_sub_if_data *sdata);
235 void ieee80211_mesh_root_setup(struct ieee80211_if_mesh *ifmsh);
236 const struct ieee80211_mesh_sync_ops *ieee80211_mesh_sync_ops_get(u8 method);
237 /* wrapper for ieee80211_bss_info_change_notify() */
238 void ieee80211_mbss_info_change_notify(struct ieee80211_sub_if_data *sdata,
239 				       u32 changed);
240 
241 /* mesh power save */
242 u32 ieee80211_mps_local_status_update(struct ieee80211_sub_if_data *sdata);
243 u32 ieee80211_mps_set_sta_local_pm(struct sta_info *sta,
244 				   enum nl80211_mesh_power_mode pm);
245 void ieee80211_mps_set_frame_flags(struct ieee80211_sub_if_data *sdata,
246 				   struct sta_info *sta,
247 				   struct ieee80211_hdr *hdr);
248 void ieee80211_mps_sta_status_update(struct sta_info *sta);
249 void ieee80211_mps_rx_h_sta_process(struct sta_info *sta,
250 				    struct ieee80211_hdr *hdr);
251 void ieee80211_mpsp_trigger_process(u8 *qc, struct sta_info *sta,
252 				    bool tx, bool acked);
253 void ieee80211_mps_frame_release(struct sta_info *sta,
254 				 struct ieee802_11_elems *elems);
255 
256 /* Mesh paths */
257 int mesh_nexthop_lookup(struct ieee80211_sub_if_data *sdata,
258 			struct sk_buff *skb);
259 int mesh_nexthop_resolve(struct ieee80211_sub_if_data *sdata,
260 			 struct sk_buff *skb);
261 void mesh_path_start_discovery(struct ieee80211_sub_if_data *sdata);
262 struct mesh_path *mesh_path_lookup(struct ieee80211_sub_if_data *sdata,
263 				   const u8 *dst);
264 struct mesh_path *mpp_path_lookup(struct ieee80211_sub_if_data *sdata,
265 				  const u8 *dst);
266 int mpp_path_add(struct ieee80211_sub_if_data *sdata,
267 		 const u8 *dst, const u8 *mpp);
268 struct mesh_path *
269 mesh_path_lookup_by_idx(struct ieee80211_sub_if_data *sdata, int idx);
270 struct mesh_path *
271 mpp_path_lookup_by_idx(struct ieee80211_sub_if_data *sdata, int idx);
272 void mesh_path_fix_nexthop(struct mesh_path *mpath, struct sta_info *next_hop);
273 void mesh_path_expire(struct ieee80211_sub_if_data *sdata);
274 void mesh_rx_path_sel_frame(struct ieee80211_sub_if_data *sdata,
275 			    struct ieee80211_mgmt *mgmt, size_t len);
276 struct mesh_path *
277 mesh_path_add(struct ieee80211_sub_if_data *sdata, const u8 *dst);
278 
279 int mesh_path_add_gate(struct mesh_path *mpath);
280 int mesh_path_send_to_gates(struct mesh_path *mpath);
281 int mesh_gate_num(struct ieee80211_sub_if_data *sdata);
282 u32 airtime_link_metric_get(struct ieee80211_local *local,
283 			    struct sta_info *sta);
284 
285 /* Mesh plinks */
286 void mesh_neighbour_update(struct ieee80211_sub_if_data *sdata,
287 			   u8 *hw_addr, struct ieee802_11_elems *ie,
288 			   struct ieee80211_rx_status *rx_status);
289 bool mesh_peer_accepts_plinks(struct ieee802_11_elems *ie);
290 u32 mesh_accept_plinks_update(struct ieee80211_sub_if_data *sdata);
291 void mesh_plink_timer(struct timer_list *t);
292 void mesh_plink_broken(struct sta_info *sta);
293 u32 mesh_plink_deactivate(struct sta_info *sta);
294 u32 mesh_plink_open(struct sta_info *sta);
295 u32 mesh_plink_block(struct sta_info *sta);
296 void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata,
297 			 struct ieee80211_mgmt *mgmt, size_t len,
298 			 struct ieee80211_rx_status *rx_status);
299 void mesh_sta_cleanup(struct sta_info *sta);
300 
301 /* Private interfaces */
302 /* Mesh paths */
303 int mesh_path_error_tx(struct ieee80211_sub_if_data *sdata,
304 		       u8 ttl, const u8 *target, u32 target_sn,
305 		       u16 target_rcode, const u8 *ra);
306 void mesh_path_assign_nexthop(struct mesh_path *mpath, struct sta_info *sta);
307 void mesh_path_flush_pending(struct mesh_path *mpath);
308 void mesh_path_tx_pending(struct mesh_path *mpath);
309 int mesh_pathtbl_init(struct ieee80211_sub_if_data *sdata);
310 void mesh_pathtbl_unregister(struct ieee80211_sub_if_data *sdata);
311 int mesh_path_del(struct ieee80211_sub_if_data *sdata, const u8 *addr);
312 void mesh_path_timer(struct timer_list *t);
313 void mesh_path_flush_by_nexthop(struct sta_info *sta);
314 void mesh_path_discard_frame(struct ieee80211_sub_if_data *sdata,
315 			     struct sk_buff *skb);
316 void mesh_path_tx_root_frame(struct ieee80211_sub_if_data *sdata);
317 
318 bool mesh_action_is_path_sel(struct ieee80211_mgmt *mgmt);
319 
320 #ifdef CONFIG_MAC80211_MESH
321 static inline
322 u32 mesh_plink_inc_estab_count(struct ieee80211_sub_if_data *sdata)
323 {
324 	atomic_inc(&sdata->u.mesh.estab_plinks);
325 	return mesh_accept_plinks_update(sdata) | BSS_CHANGED_BEACON;
326 }
327 
328 static inline
329 u32 mesh_plink_dec_estab_count(struct ieee80211_sub_if_data *sdata)
330 {
331 	atomic_dec(&sdata->u.mesh.estab_plinks);
332 	return mesh_accept_plinks_update(sdata) | BSS_CHANGED_BEACON;
333 }
334 
335 static inline int mesh_plink_free_count(struct ieee80211_sub_if_data *sdata)
336 {
337 	return sdata->u.mesh.mshcfg.dot11MeshMaxPeerLinks -
338 	       atomic_read(&sdata->u.mesh.estab_plinks);
339 }
340 
341 static inline bool mesh_plink_availables(struct ieee80211_sub_if_data *sdata)
342 {
343 	return (min_t(long, mesh_plink_free_count(sdata),
344 		   MESH_MAX_PLINKS - sdata->local->num_sta)) > 0;
345 }
346 
347 static inline void mesh_path_activate(struct mesh_path *mpath)
348 {
349 	mpath->flags |= MESH_PATH_ACTIVE | MESH_PATH_RESOLVED;
350 }
351 
352 static inline bool mesh_path_sel_is_hwmp(struct ieee80211_sub_if_data *sdata)
353 {
354 	return sdata->u.mesh.mesh_pp_id == IEEE80211_PATH_PROTOCOL_HWMP;
355 }
356 
357 void mesh_path_flush_by_iface(struct ieee80211_sub_if_data *sdata);
358 void mesh_sync_adjust_tsf(struct ieee80211_sub_if_data *sdata);
359 void ieee80211s_stop(void);
360 #else
361 static inline bool mesh_path_sel_is_hwmp(struct ieee80211_sub_if_data *sdata)
362 { return false; }
363 static inline void mesh_path_flush_by_iface(struct ieee80211_sub_if_data *sdata)
364 {}
365 static inline void ieee80211s_stop(void) {}
366 #endif
367 
368 #endif /* IEEE80211S_H */
369