xref: /openbmc/linux/net/mac80211/mesh.h (revision 8b030a57)
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  *
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 walk_list;
110 	struct hlist_node gate_list;
111 	struct ieee80211_sub_if_data *sdata;
112 	struct sta_info __rcu *next_hop;
113 	struct timer_list timer;
114 	struct sk_buff_head frame_queue;
115 	struct rcu_head rcu;
116 	u32 sn;
117 	u32 metric;
118 	u8 hop_count;
119 	unsigned long exp_time;
120 	u32 discovery_timeout;
121 	u8 discovery_retries;
122 	enum mesh_path_flags flags;
123 	spinlock_t state_lock;
124 	u8 rann_snd_addr[ETH_ALEN];
125 	u32 rann_metric;
126 	unsigned long last_preq_to_root;
127 	bool is_root;
128 	bool is_gate;
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  * @walk_head: linked list containging all mesh_path objects
139  * @walk_lock: lock protecting walk_head
140  * @entries: number of entries in the table
141  */
142 struct mesh_table {
143 	struct hlist_head known_gates;
144 	spinlock_t gates_lock;
145 	struct rhashtable rhead;
146 	struct hlist_head walk_head;
147 	spinlock_t walk_lock;
148 	atomic_t entries;		/* Up to MAX_MESH_NEIGHBOURS */
149 };
150 
151 /* Recent multicast cache */
152 /* RMC_BUCKETS must be a power of 2, maximum 256 */
153 #define RMC_BUCKETS		256
154 #define RMC_QUEUE_MAX_LEN	4
155 #define RMC_TIMEOUT		(3 * HZ)
156 
157 /**
158  * struct rmc_entry - entry in the Recent Multicast Cache
159  *
160  * @seqnum: mesh sequence number of the frame
161  * @exp_time: expiration time of the entry, in jiffies
162  * @sa: source address of the frame
163  * @list: hashtable list pointer
164  *
165  * The Recent Multicast Cache keeps track of the latest multicast frames that
166  * have been received by a mesh interface and discards received multicast frames
167  * that are found in the cache.
168  */
169 struct rmc_entry {
170 	struct hlist_node list;
171 	unsigned long exp_time;
172 	u32 seqnum;
173 	u8 sa[ETH_ALEN];
174 };
175 
176 struct mesh_rmc {
177 	struct hlist_head bucket[RMC_BUCKETS];
178 	u32 idx_mask;
179 };
180 
181 #define IEEE80211_MESH_HOUSEKEEPING_INTERVAL (60 * HZ)
182 
183 #define MESH_PATH_EXPIRE (600 * HZ)
184 
185 /* Default maximum number of plinks per interface */
186 #define MESH_MAX_PLINKS		256
187 
188 /* Maximum number of paths per interface */
189 #define MESH_MAX_MPATHS		1024
190 
191 /* Number of frames buffered per destination for unresolved destinations */
192 #define MESH_FRAME_QUEUE_LEN	10
193 
194 /* Public interfaces */
195 /* Various */
196 int ieee80211_fill_mesh_addresses(struct ieee80211_hdr *hdr, __le16 *fc,
197 				  const u8 *da, const u8 *sa);
198 unsigned int ieee80211_new_mesh_header(struct ieee80211_sub_if_data *sdata,
199 				       struct ieee80211s_hdr *meshhdr,
200 				       const char *addr4or5, const char *addr6);
201 int mesh_rmc_check(struct ieee80211_sub_if_data *sdata,
202 		   const u8 *addr, struct ieee80211s_hdr *mesh_hdr);
203 bool mesh_matches_local(struct ieee80211_sub_if_data *sdata,
204 			struct ieee802_11_elems *ie);
205 void mesh_ids_set_default(struct ieee80211_if_mesh *mesh);
206 int mesh_add_meshconf_ie(struct ieee80211_sub_if_data *sdata,
207 			 struct sk_buff *skb);
208 int mesh_add_meshid_ie(struct ieee80211_sub_if_data *sdata,
209 		       struct sk_buff *skb);
210 int mesh_add_rsn_ie(struct ieee80211_sub_if_data *sdata,
211 		    struct sk_buff *skb);
212 int mesh_add_vendor_ies(struct ieee80211_sub_if_data *sdata,
213 			struct sk_buff *skb);
214 int mesh_add_ht_cap_ie(struct ieee80211_sub_if_data *sdata,
215 		       struct sk_buff *skb);
216 int mesh_add_ht_oper_ie(struct ieee80211_sub_if_data *sdata,
217 			struct sk_buff *skb);
218 int mesh_add_vht_cap_ie(struct ieee80211_sub_if_data *sdata,
219 			struct sk_buff *skb);
220 int mesh_add_vht_oper_ie(struct ieee80211_sub_if_data *sdata,
221 			 struct sk_buff *skb);
222 void mesh_rmc_free(struct ieee80211_sub_if_data *sdata);
223 int mesh_rmc_init(struct ieee80211_sub_if_data *sdata);
224 void ieee80211s_init(void);
225 void ieee80211s_update_metric(struct ieee80211_local *local,
226 			      struct sta_info *sta,
227 			      struct ieee80211_tx_status *st);
228 void ieee80211_mesh_init_sdata(struct ieee80211_sub_if_data *sdata);
229 void ieee80211_mesh_teardown_sdata(struct ieee80211_sub_if_data *sdata);
230 int ieee80211_start_mesh(struct ieee80211_sub_if_data *sdata);
231 void ieee80211_stop_mesh(struct ieee80211_sub_if_data *sdata);
232 void ieee80211_mesh_root_setup(struct ieee80211_if_mesh *ifmsh);
233 const struct ieee80211_mesh_sync_ops *ieee80211_mesh_sync_ops_get(u8 method);
234 /* wrapper for ieee80211_bss_info_change_notify() */
235 void ieee80211_mbss_info_change_notify(struct ieee80211_sub_if_data *sdata,
236 				       u32 changed);
237 
238 /* mesh power save */
239 u32 ieee80211_mps_local_status_update(struct ieee80211_sub_if_data *sdata);
240 u32 ieee80211_mps_set_sta_local_pm(struct sta_info *sta,
241 				   enum nl80211_mesh_power_mode pm);
242 void ieee80211_mps_set_frame_flags(struct ieee80211_sub_if_data *sdata,
243 				   struct sta_info *sta,
244 				   struct ieee80211_hdr *hdr);
245 void ieee80211_mps_sta_status_update(struct sta_info *sta);
246 void ieee80211_mps_rx_h_sta_process(struct sta_info *sta,
247 				    struct ieee80211_hdr *hdr);
248 void ieee80211_mpsp_trigger_process(u8 *qc, struct sta_info *sta,
249 				    bool tx, bool acked);
250 void ieee80211_mps_frame_release(struct sta_info *sta,
251 				 struct ieee802_11_elems *elems);
252 
253 /* Mesh paths */
254 int mesh_nexthop_lookup(struct ieee80211_sub_if_data *sdata,
255 			struct sk_buff *skb);
256 int mesh_nexthop_resolve(struct ieee80211_sub_if_data *sdata,
257 			 struct sk_buff *skb);
258 void mesh_path_start_discovery(struct ieee80211_sub_if_data *sdata);
259 struct mesh_path *mesh_path_lookup(struct ieee80211_sub_if_data *sdata,
260 				   const u8 *dst);
261 struct mesh_path *mpp_path_lookup(struct ieee80211_sub_if_data *sdata,
262 				  const u8 *dst);
263 int mpp_path_add(struct ieee80211_sub_if_data *sdata,
264 		 const u8 *dst, const u8 *mpp);
265 struct mesh_path *
266 mesh_path_lookup_by_idx(struct ieee80211_sub_if_data *sdata, int idx);
267 struct mesh_path *
268 mpp_path_lookup_by_idx(struct ieee80211_sub_if_data *sdata, int idx);
269 void mesh_path_fix_nexthop(struct mesh_path *mpath, struct sta_info *next_hop);
270 void mesh_path_expire(struct ieee80211_sub_if_data *sdata);
271 void mesh_rx_path_sel_frame(struct ieee80211_sub_if_data *sdata,
272 			    struct ieee80211_mgmt *mgmt, size_t len);
273 struct mesh_path *
274 mesh_path_add(struct ieee80211_sub_if_data *sdata, const u8 *dst);
275 
276 int mesh_path_add_gate(struct mesh_path *mpath);
277 int mesh_path_send_to_gates(struct mesh_path *mpath);
278 int mesh_gate_num(struct ieee80211_sub_if_data *sdata);
279 
280 /* Mesh plinks */
281 void mesh_neighbour_update(struct ieee80211_sub_if_data *sdata,
282 			   u8 *hw_addr, struct ieee802_11_elems *ie,
283 			   struct ieee80211_rx_status *rx_status);
284 bool mesh_peer_accepts_plinks(struct ieee802_11_elems *ie);
285 u32 mesh_accept_plinks_update(struct ieee80211_sub_if_data *sdata);
286 void mesh_plink_timer(struct timer_list *t);
287 void mesh_plink_broken(struct sta_info *sta);
288 u32 mesh_plink_deactivate(struct sta_info *sta);
289 u32 mesh_plink_open(struct sta_info *sta);
290 u32 mesh_plink_block(struct sta_info *sta);
291 void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata,
292 			 struct ieee80211_mgmt *mgmt, size_t len,
293 			 struct ieee80211_rx_status *rx_status);
294 void mesh_sta_cleanup(struct sta_info *sta);
295 
296 /* Private interfaces */
297 /* Mesh paths */
298 int mesh_path_error_tx(struct ieee80211_sub_if_data *sdata,
299 		       u8 ttl, const u8 *target, u32 target_sn,
300 		       u16 target_rcode, const u8 *ra);
301 void mesh_path_assign_nexthop(struct mesh_path *mpath, struct sta_info *sta);
302 void mesh_path_flush_pending(struct mesh_path *mpath);
303 void mesh_path_tx_pending(struct mesh_path *mpath);
304 int mesh_pathtbl_init(struct ieee80211_sub_if_data *sdata);
305 void mesh_pathtbl_unregister(struct ieee80211_sub_if_data *sdata);
306 int mesh_path_del(struct ieee80211_sub_if_data *sdata, const u8 *addr);
307 void mesh_path_timer(struct timer_list *t);
308 void mesh_path_flush_by_nexthop(struct sta_info *sta);
309 void mesh_path_discard_frame(struct ieee80211_sub_if_data *sdata,
310 			     struct sk_buff *skb);
311 void mesh_path_tx_root_frame(struct ieee80211_sub_if_data *sdata);
312 
313 bool mesh_action_is_path_sel(struct ieee80211_mgmt *mgmt);
314 
315 #ifdef CONFIG_MAC80211_MESH
316 static inline
317 u32 mesh_plink_inc_estab_count(struct ieee80211_sub_if_data *sdata)
318 {
319 	atomic_inc(&sdata->u.mesh.estab_plinks);
320 	return mesh_accept_plinks_update(sdata) | BSS_CHANGED_BEACON;
321 }
322 
323 static inline
324 u32 mesh_plink_dec_estab_count(struct ieee80211_sub_if_data *sdata)
325 {
326 	atomic_dec(&sdata->u.mesh.estab_plinks);
327 	return mesh_accept_plinks_update(sdata) | BSS_CHANGED_BEACON;
328 }
329 
330 static inline int mesh_plink_free_count(struct ieee80211_sub_if_data *sdata)
331 {
332 	return sdata->u.mesh.mshcfg.dot11MeshMaxPeerLinks -
333 	       atomic_read(&sdata->u.mesh.estab_plinks);
334 }
335 
336 static inline bool mesh_plink_availables(struct ieee80211_sub_if_data *sdata)
337 {
338 	return (min_t(long, mesh_plink_free_count(sdata),
339 		   MESH_MAX_PLINKS - sdata->local->num_sta)) > 0;
340 }
341 
342 static inline void mesh_path_activate(struct mesh_path *mpath)
343 {
344 	mpath->flags |= MESH_PATH_ACTIVE | MESH_PATH_RESOLVED;
345 }
346 
347 static inline bool mesh_path_sel_is_hwmp(struct ieee80211_sub_if_data *sdata)
348 {
349 	return sdata->u.mesh.mesh_pp_id == IEEE80211_PATH_PROTOCOL_HWMP;
350 }
351 
352 void mesh_path_flush_by_iface(struct ieee80211_sub_if_data *sdata);
353 void mesh_sync_adjust_tsf(struct ieee80211_sub_if_data *sdata);
354 void ieee80211s_stop(void);
355 #else
356 static inline bool mesh_path_sel_is_hwmp(struct ieee80211_sub_if_data *sdata)
357 { return false; }
358 static inline void mesh_path_flush_by_iface(struct ieee80211_sub_if_data *sdata)
359 {}
360 static inline void ieee80211s_stop(void) {}
361 #endif
362 
363 #endif /* IEEE80211S_H */
364