xref: /openbmc/linux/net/mac80211/mesh.h (revision aac5987a)
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  *
98  *
99  * The dst address is unique in the mesh path table. Since the mesh_path is
100  * protected by RCU, deleting the next_hop STA must remove / substitute the
101  * mesh_path structure and wait until that is no longer reachable before
102  * destroying the STA completely.
103  */
104 struct mesh_path {
105 	u8 dst[ETH_ALEN];
106 	u8 mpp[ETH_ALEN];	/* used for MPP or MAP */
107 	struct rhash_head rhash;
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 };
128 
129 /**
130  * struct mesh_table
131  *
132  * @known_gates: list of known mesh gates and their mpaths by the station. The
133  * gate's mpath may or may not be resolved and active.
134  * @gates_lock: protects updates to known_gates
135  * @rhead: the rhashtable containing struct mesh_paths, keyed by dest addr
136  * @entries: number of entries in the table
137  */
138 struct mesh_table {
139 	struct hlist_head known_gates;
140 	spinlock_t gates_lock;
141 	struct rhashtable rhead;
142 	atomic_t entries;		/* Up to MAX_MESH_NEIGHBOURS */
143 };
144 
145 /* Recent multicast cache */
146 /* RMC_BUCKETS must be a power of 2, maximum 256 */
147 #define RMC_BUCKETS		256
148 #define RMC_QUEUE_MAX_LEN	4
149 #define RMC_TIMEOUT		(3 * HZ)
150 
151 /**
152  * struct rmc_entry - entry in the Recent Multicast Cache
153  *
154  * @seqnum: mesh sequence number of the frame
155  * @exp_time: expiration time of the entry, in jiffies
156  * @sa: source address of the frame
157  * @list: hashtable list pointer
158  *
159  * The Recent Multicast Cache keeps track of the latest multicast frames that
160  * have been received by a mesh interface and discards received multicast frames
161  * that are found in the cache.
162  */
163 struct rmc_entry {
164 	struct hlist_node list;
165 	unsigned long exp_time;
166 	u32 seqnum;
167 	u8 sa[ETH_ALEN];
168 };
169 
170 struct mesh_rmc {
171 	struct hlist_head bucket[RMC_BUCKETS];
172 	u32 idx_mask;
173 };
174 
175 #define IEEE80211_MESH_HOUSEKEEPING_INTERVAL (60 * HZ)
176 
177 #define MESH_PATH_EXPIRE (600 * HZ)
178 
179 /* Default maximum number of plinks per interface */
180 #define MESH_MAX_PLINKS		256
181 
182 /* Maximum number of paths per interface */
183 #define MESH_MAX_MPATHS		1024
184 
185 /* Number of frames buffered per destination for unresolved destinations */
186 #define MESH_FRAME_QUEUE_LEN	10
187 
188 /* Public interfaces */
189 /* Various */
190 int ieee80211_fill_mesh_addresses(struct ieee80211_hdr *hdr, __le16 *fc,
191 				  const u8 *da, const u8 *sa);
192 unsigned int ieee80211_new_mesh_header(struct ieee80211_sub_if_data *sdata,
193 				       struct ieee80211s_hdr *meshhdr,
194 				       const char *addr4or5, const char *addr6);
195 int mesh_rmc_check(struct ieee80211_sub_if_data *sdata,
196 		   const u8 *addr, struct ieee80211s_hdr *mesh_hdr);
197 bool mesh_matches_local(struct ieee80211_sub_if_data *sdata,
198 			struct ieee802_11_elems *ie);
199 void mesh_ids_set_default(struct ieee80211_if_mesh *mesh);
200 int mesh_add_meshconf_ie(struct ieee80211_sub_if_data *sdata,
201 			 struct sk_buff *skb);
202 int mesh_add_meshid_ie(struct ieee80211_sub_if_data *sdata,
203 		       struct sk_buff *skb);
204 int mesh_add_rsn_ie(struct ieee80211_sub_if_data *sdata,
205 		    struct sk_buff *skb);
206 int mesh_add_vendor_ies(struct ieee80211_sub_if_data *sdata,
207 			struct sk_buff *skb);
208 int mesh_add_ht_cap_ie(struct ieee80211_sub_if_data *sdata,
209 		       struct sk_buff *skb);
210 int mesh_add_ht_oper_ie(struct ieee80211_sub_if_data *sdata,
211 			struct sk_buff *skb);
212 int mesh_add_vht_cap_ie(struct ieee80211_sub_if_data *sdata,
213 			struct sk_buff *skb);
214 int mesh_add_vht_oper_ie(struct ieee80211_sub_if_data *sdata,
215 			 struct sk_buff *skb);
216 void mesh_rmc_free(struct ieee80211_sub_if_data *sdata);
217 int mesh_rmc_init(struct ieee80211_sub_if_data *sdata);
218 void ieee80211s_init(void);
219 void ieee80211s_update_metric(struct ieee80211_local *local,
220 			      struct sta_info *sta, struct sk_buff *skb);
221 void ieee80211_mesh_init_sdata(struct ieee80211_sub_if_data *sdata);
222 void ieee80211_mesh_teardown_sdata(struct ieee80211_sub_if_data *sdata);
223 int ieee80211_start_mesh(struct ieee80211_sub_if_data *sdata);
224 void ieee80211_stop_mesh(struct ieee80211_sub_if_data *sdata);
225 void ieee80211_mesh_root_setup(struct ieee80211_if_mesh *ifmsh);
226 const struct ieee80211_mesh_sync_ops *ieee80211_mesh_sync_ops_get(u8 method);
227 /* wrapper for ieee80211_bss_info_change_notify() */
228 void ieee80211_mbss_info_change_notify(struct ieee80211_sub_if_data *sdata,
229 				       u32 changed);
230 
231 /* mesh power save */
232 u32 ieee80211_mps_local_status_update(struct ieee80211_sub_if_data *sdata);
233 u32 ieee80211_mps_set_sta_local_pm(struct sta_info *sta,
234 				   enum nl80211_mesh_power_mode pm);
235 void ieee80211_mps_set_frame_flags(struct ieee80211_sub_if_data *sdata,
236 				   struct sta_info *sta,
237 				   struct ieee80211_hdr *hdr);
238 void ieee80211_mps_sta_status_update(struct sta_info *sta);
239 void ieee80211_mps_rx_h_sta_process(struct sta_info *sta,
240 				    struct ieee80211_hdr *hdr);
241 void ieee80211_mpsp_trigger_process(u8 *qc, struct sta_info *sta,
242 				    bool tx, bool acked);
243 void ieee80211_mps_frame_release(struct sta_info *sta,
244 				 struct ieee802_11_elems *elems);
245 
246 /* Mesh paths */
247 int mesh_nexthop_lookup(struct ieee80211_sub_if_data *sdata,
248 			struct sk_buff *skb);
249 int mesh_nexthop_resolve(struct ieee80211_sub_if_data *sdata,
250 			 struct sk_buff *skb);
251 void mesh_path_start_discovery(struct ieee80211_sub_if_data *sdata);
252 struct mesh_path *mesh_path_lookup(struct ieee80211_sub_if_data *sdata,
253 				   const u8 *dst);
254 struct mesh_path *mpp_path_lookup(struct ieee80211_sub_if_data *sdata,
255 				  const u8 *dst);
256 int mpp_path_add(struct ieee80211_sub_if_data *sdata,
257 		 const u8 *dst, const u8 *mpp);
258 struct mesh_path *
259 mesh_path_lookup_by_idx(struct ieee80211_sub_if_data *sdata, int idx);
260 struct mesh_path *
261 mpp_path_lookup_by_idx(struct ieee80211_sub_if_data *sdata, int idx);
262 void mesh_path_fix_nexthop(struct mesh_path *mpath, struct sta_info *next_hop);
263 void mesh_path_expire(struct ieee80211_sub_if_data *sdata);
264 void mesh_rx_path_sel_frame(struct ieee80211_sub_if_data *sdata,
265 			    struct ieee80211_mgmt *mgmt, size_t len);
266 struct mesh_path *
267 mesh_path_add(struct ieee80211_sub_if_data *sdata, const u8 *dst);
268 
269 int mesh_path_add_gate(struct mesh_path *mpath);
270 int mesh_path_send_to_gates(struct mesh_path *mpath);
271 int mesh_gate_num(struct ieee80211_sub_if_data *sdata);
272 
273 /* Mesh plinks */
274 void mesh_neighbour_update(struct ieee80211_sub_if_data *sdata,
275 			   u8 *hw_addr, struct ieee802_11_elems *ie);
276 bool mesh_peer_accepts_plinks(struct ieee802_11_elems *ie);
277 u32 mesh_accept_plinks_update(struct ieee80211_sub_if_data *sdata);
278 void mesh_plink_broken(struct sta_info *sta);
279 u32 mesh_plink_deactivate(struct sta_info *sta);
280 u32 mesh_plink_open(struct sta_info *sta);
281 u32 mesh_plink_block(struct sta_info *sta);
282 void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata,
283 			 struct ieee80211_mgmt *mgmt, size_t len,
284 			 struct ieee80211_rx_status *rx_status);
285 void mesh_sta_cleanup(struct sta_info *sta);
286 
287 /* Private interfaces */
288 /* Mesh paths */
289 int mesh_path_error_tx(struct ieee80211_sub_if_data *sdata,
290 		       u8 ttl, const u8 *target, u32 target_sn,
291 		       u16 target_rcode, const u8 *ra);
292 void mesh_path_assign_nexthop(struct mesh_path *mpath, struct sta_info *sta);
293 void mesh_path_flush_pending(struct mesh_path *mpath);
294 void mesh_path_tx_pending(struct mesh_path *mpath);
295 int mesh_pathtbl_init(struct ieee80211_sub_if_data *sdata);
296 void mesh_pathtbl_unregister(struct ieee80211_sub_if_data *sdata);
297 int mesh_path_del(struct ieee80211_sub_if_data *sdata, const u8 *addr);
298 void mesh_path_timer(unsigned long data);
299 void mesh_path_flush_by_nexthop(struct sta_info *sta);
300 void mesh_path_discard_frame(struct ieee80211_sub_if_data *sdata,
301 			     struct sk_buff *skb);
302 void mesh_path_tx_root_frame(struct ieee80211_sub_if_data *sdata);
303 
304 bool mesh_action_is_path_sel(struct ieee80211_mgmt *mgmt);
305 
306 #ifdef CONFIG_MAC80211_MESH
307 static inline
308 u32 mesh_plink_inc_estab_count(struct ieee80211_sub_if_data *sdata)
309 {
310 	atomic_inc(&sdata->u.mesh.estab_plinks);
311 	return mesh_accept_plinks_update(sdata) | BSS_CHANGED_BEACON;
312 }
313 
314 static inline
315 u32 mesh_plink_dec_estab_count(struct ieee80211_sub_if_data *sdata)
316 {
317 	atomic_dec(&sdata->u.mesh.estab_plinks);
318 	return mesh_accept_plinks_update(sdata) | BSS_CHANGED_BEACON;
319 }
320 
321 static inline int mesh_plink_free_count(struct ieee80211_sub_if_data *sdata)
322 {
323 	return sdata->u.mesh.mshcfg.dot11MeshMaxPeerLinks -
324 	       atomic_read(&sdata->u.mesh.estab_plinks);
325 }
326 
327 static inline bool mesh_plink_availables(struct ieee80211_sub_if_data *sdata)
328 {
329 	return (min_t(long, mesh_plink_free_count(sdata),
330 		   MESH_MAX_PLINKS - sdata->local->num_sta)) > 0;
331 }
332 
333 static inline void mesh_path_activate(struct mesh_path *mpath)
334 {
335 	mpath->flags |= MESH_PATH_ACTIVE | MESH_PATH_RESOLVED;
336 }
337 
338 static inline bool mesh_path_sel_is_hwmp(struct ieee80211_sub_if_data *sdata)
339 {
340 	return sdata->u.mesh.mesh_pp_id == IEEE80211_PATH_PROTOCOL_HWMP;
341 }
342 
343 void mesh_path_flush_by_iface(struct ieee80211_sub_if_data *sdata);
344 void mesh_sync_adjust_tsf(struct ieee80211_sub_if_data *sdata);
345 void ieee80211s_stop(void);
346 #else
347 static inline bool mesh_path_sel_is_hwmp(struct ieee80211_sub_if_data *sdata)
348 { return false; }
349 static inline void mesh_path_flush_by_iface(struct ieee80211_sub_if_data *sdata)
350 {}
351 static inline void ieee80211s_stop(void) {}
352 #endif
353 
354 #endif /* IEEE80211S_H */
355