1 /*
2  * Copyright 2002-2005, Devicescape Software, Inc.
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License version 2 as
6  * published by the Free Software Foundation.
7  */
8 
9 #ifndef STA_INFO_H
10 #define STA_INFO_H
11 
12 #include <linux/list.h>
13 #include <linux/types.h>
14 #include <linux/if_ether.h>
15 #include <linux/workqueue.h>
16 #include <linux/average.h>
17 #include "key.h"
18 
19 /**
20  * enum ieee80211_sta_info_flags - Stations flags
21  *
22  * These flags are used with &struct sta_info's @flags member.
23  *
24  * @WLAN_STA_AUTH: Station is authenticated.
25  * @WLAN_STA_ASSOC: Station is associated.
26  * @WLAN_STA_PS_STA: Station is in power-save mode
27  * @WLAN_STA_AUTHORIZED: Station is authorized to send/receive traffic.
28  *	This bit is always checked so needs to be enabled for all stations
29  *	when virtual port control is not in use.
30  * @WLAN_STA_SHORT_PREAMBLE: Station is capable of receiving short-preamble
31  *	frames.
32  * @WLAN_STA_ASSOC_AP: We're associated to that station, it is an AP.
33  * @WLAN_STA_WME: Station is a QoS-STA.
34  * @WLAN_STA_WDS: Station is one of our WDS peers.
35  * @WLAN_STA_CLEAR_PS_FILT: Clear PS filter in hardware (using the
36  *	IEEE80211_TX_CTL_CLEAR_PS_FILT control flag) when the next
37  *	frame to this station is transmitted.
38  * @WLAN_STA_MFP: Management frame protection is used with this STA.
39  * @WLAN_STA_BLOCK_BA: Used to deny ADDBA requests (both TX and RX)
40  *	during suspend/resume and station removal.
41  * @WLAN_STA_PS_DRIVER: driver requires keeping this station in
42  *	power-save mode logically to flush frames that might still
43  *	be in the queues
44  * @WLAN_STA_PSPOLL: Station sent PS-poll while driver was keeping
45  *	station in power-save mode, reply when the driver unblocks.
46  */
47 enum ieee80211_sta_info_flags {
48 	WLAN_STA_AUTH		= 1<<0,
49 	WLAN_STA_ASSOC		= 1<<1,
50 	WLAN_STA_PS_STA		= 1<<2,
51 	WLAN_STA_AUTHORIZED	= 1<<3,
52 	WLAN_STA_SHORT_PREAMBLE	= 1<<4,
53 	WLAN_STA_ASSOC_AP	= 1<<5,
54 	WLAN_STA_WME		= 1<<6,
55 	WLAN_STA_WDS		= 1<<7,
56 	WLAN_STA_CLEAR_PS_FILT	= 1<<9,
57 	WLAN_STA_MFP		= 1<<10,
58 	WLAN_STA_BLOCK_BA	= 1<<11,
59 	WLAN_STA_PS_DRIVER	= 1<<12,
60 	WLAN_STA_PSPOLL		= 1<<13,
61 };
62 
63 #define STA_TID_NUM 16
64 #define ADDBA_RESP_INTERVAL HZ
65 #define HT_AGG_MAX_RETRIES		0x3
66 
67 #define HT_AGG_STATE_DRV_READY		0
68 #define HT_AGG_STATE_RESPONSE_RECEIVED	1
69 #define HT_AGG_STATE_OPERATIONAL	2
70 #define HT_AGG_STATE_STOPPING		3
71 #define HT_AGG_STATE_WANT_START		4
72 #define HT_AGG_STATE_WANT_STOP		5
73 
74 /**
75  * struct tid_ampdu_tx - TID aggregation information (Tx).
76  *
77  * @rcu_head: rcu head for freeing structure
78  * @addba_resp_timer: timer for peer's response to addba request
79  * @pending: pending frames queue -- use sta's spinlock to protect
80  * @dialog_token: dialog token for aggregation session
81  * @timeout: session timeout value to be filled in ADDBA requests
82  * @state: session state (see above)
83  * @stop_initiator: initiator of a session stop
84  * @tx_stop: TX DelBA frame when stopping
85  * @buf_size: reorder buffer size at receiver
86  *
87  * This structure's lifetime is managed by RCU, assignments to
88  * the array holding it must hold the aggregation mutex.
89  *
90  * The TX path can access it under RCU lock-free if, and
91  * only if, the state has the flag %HT_AGG_STATE_OPERATIONAL
92  * set. Otherwise, the TX path must also acquire the spinlock
93  * and re-check the state, see comments in the tx code
94  * touching it.
95  */
96 struct tid_ampdu_tx {
97 	struct rcu_head rcu_head;
98 	struct timer_list addba_resp_timer;
99 	struct sk_buff_head pending;
100 	unsigned long state;
101 	u16 timeout;
102 	u8 dialog_token;
103 	u8 stop_initiator;
104 	bool tx_stop;
105 	u8 buf_size;
106 };
107 
108 /**
109  * struct tid_ampdu_rx - TID aggregation information (Rx).
110  *
111  * @reorder_buf: buffer to reorder incoming aggregated MPDUs
112  * @reorder_time: jiffies when skb was added
113  * @session_timer: check if peer keeps Tx-ing on the TID (by timeout value)
114  * @reorder_timer: releases expired frames from the reorder buffer.
115  * @head_seq_num: head sequence number in reordering buffer.
116  * @stored_mpdu_num: number of MPDUs in reordering buffer
117  * @ssn: Starting Sequence Number expected to be aggregated.
118  * @buf_size: buffer size for incoming A-MPDUs
119  * @timeout: reset timer value (in TUs).
120  * @dialog_token: dialog token for aggregation session
121  * @rcu_head: RCU head used for freeing this struct
122  * @reorder_lock: serializes access to reorder buffer, see below.
123  *
124  * This structure's lifetime is managed by RCU, assignments to
125  * the array holding it must hold the aggregation mutex.
126  *
127  * The @reorder_lock is used to protect the members of this
128  * struct, except for @timeout, @buf_size and @dialog_token,
129  * which are constant across the lifetime of the struct (the
130  * dialog token being used only for debugging).
131  */
132 struct tid_ampdu_rx {
133 	struct rcu_head rcu_head;
134 	spinlock_t reorder_lock;
135 	struct sk_buff **reorder_buf;
136 	unsigned long *reorder_time;
137 	struct timer_list session_timer;
138 	struct timer_list reorder_timer;
139 	u16 head_seq_num;
140 	u16 stored_mpdu_num;
141 	u16 ssn;
142 	u16 buf_size;
143 	u16 timeout;
144 	u8 dialog_token;
145 };
146 
147 /**
148  * struct sta_ampdu_mlme - STA aggregation information.
149  *
150  * @tid_rx: aggregation info for Rx per TID -- RCU protected
151  * @tid_tx: aggregation info for Tx per TID
152  * @addba_req_num: number of times addBA request has been sent.
153  * @dialog_token_allocator: dialog token enumerator for each new session;
154  * @work: work struct for starting/stopping aggregation
155  * @tid_rx_timer_expired: bitmap indicating on which TIDs the
156  *	RX timer expired until the work for it runs
157  * @mtx: mutex to protect all TX data (except non-NULL assignments
158  *	to tid_tx[idx], which are protected by the sta spinlock)
159  */
160 struct sta_ampdu_mlme {
161 	struct mutex mtx;
162 	/* rx */
163 	struct tid_ampdu_rx *tid_rx[STA_TID_NUM];
164 	unsigned long tid_rx_timer_expired[BITS_TO_LONGS(STA_TID_NUM)];
165 	/* tx */
166 	struct work_struct work;
167 	struct tid_ampdu_tx *tid_tx[STA_TID_NUM];
168 	u8 addba_req_num[STA_TID_NUM];
169 	u8 dialog_token_allocator;
170 };
171 
172 
173 /**
174  * enum plink_state - state of a mesh peer link finite state machine
175  *
176  * @PLINK_LISTEN: initial state, considered the implicit state of non existent
177  * 	mesh peer links
178  * @PLINK_OPN_SNT: mesh plink open frame has been sent to this mesh peer
179  * @PLINK_OPN_RCVD: mesh plink open frame has been received from this mesh peer
180  * @PLINK_CNF_RCVD: mesh plink confirm frame has been received from this mesh
181  * 	peer
182  * @PLINK_ESTAB: mesh peer link is established
183  * @PLINK_HOLDING: mesh peer link is being closed or cancelled
184  * @PLINK_BLOCKED: all frames transmitted from this mesh plink are discarded
185  */
186 enum plink_state {
187 	PLINK_LISTEN,
188 	PLINK_OPN_SNT,
189 	PLINK_OPN_RCVD,
190 	PLINK_CNF_RCVD,
191 	PLINK_ESTAB,
192 	PLINK_HOLDING,
193 	PLINK_BLOCKED
194 };
195 
196 /**
197  * struct sta_info - STA information
198  *
199  * This structure collects information about a station that
200  * mac80211 is communicating with.
201  *
202  * @list: global linked list entry
203  * @hnext: hash table linked list pointer
204  * @local: pointer to the global information
205  * @sdata: virtual interface this station belongs to
206  * @ptk: peer key negotiated with this station, if any
207  * @gtk: group keys negotiated with this station, if any
208  * @rate_ctrl: rate control algorithm reference
209  * @rate_ctrl_priv: rate control private per-STA pointer
210  * @last_tx_rate: rate used for last transmit, to report to userspace as
211  *	"the" transmit rate
212  * @last_rx_rate_idx: rx status rate index of the last data packet
213  * @last_rx_rate_flag: rx status flag of the last data packet
214  * @lock: used for locking all fields that require locking, see comments
215  *	in the header file.
216  * @flaglock: spinlock for flags accesses
217  * @drv_unblock_wk: used for driver PS unblocking
218  * @listen_interval: listen interval of this station, when we're acting as AP
219  * @flags: STA flags, see &enum ieee80211_sta_info_flags
220  * @ps_tx_buf: buffer of frames to transmit to this station
221  *	when it leaves power saving state
222  * @tx_filtered: buffer of frames we already tried to transmit
223  *	but were filtered by hardware due to STA having entered
224  *	power saving state
225  * @rx_packets: Number of MSDUs received from this STA
226  * @rx_bytes: Number of bytes received from this STA
227  * @wep_weak_iv_count: number of weak WEP IVs received from this station
228  * @last_rx: time (in jiffies) when last frame was received from this STA
229  * @num_duplicates: number of duplicate frames received from this STA
230  * @rx_fragments: number of received MPDUs
231  * @rx_dropped: number of dropped MPDUs from this STA
232  * @last_signal: signal of last received frame from this STA
233  * @avg_signal: moving average of signal of received frames from this STA
234  * @last_seq_ctrl: last received seq/frag number from this STA (per RX queue)
235  * @tx_filtered_count: number of frames the hardware filtered for this STA
236  * @tx_retry_failed: number of frames that failed retry
237  * @tx_retry_count: total number of retries for frames to this STA
238  * @fail_avg: moving percentage of failed MSDUs
239  * @tx_packets: number of RX/TX MSDUs
240  * @tx_bytes: number of bytes transmitted to this STA
241  * @tx_fragments: number of transmitted MPDUs
242  * @tid_seq: per-TID sequence numbers for sending to this STA
243  * @ampdu_mlme: A-MPDU state machine state
244  * @timer_to_tid: identity mapping to ID timers
245  * @llid: Local link ID
246  * @plid: Peer link ID
247  * @reason: Cancel reason on PLINK_HOLDING state
248  * @plink_retries: Retries in establishment
249  * @ignore_plink_timer: ignore the peer-link timer (used internally)
250  * @plink_state: peer link state
251  * @plink_timeout: timeout of peer link
252  * @plink_timer: peer link watch timer
253  * @plink_timer_was_running: used by suspend/resume to restore timers
254  * @debugfs: debug filesystem info
255  * @sta: station information we share with the driver
256  * @dead: set to true when sta is unlinked
257  * @uploaded: set to true when sta is uploaded to the driver
258  * @lost_packets: number of consecutive lost packets
259  */
260 struct sta_info {
261 	/* General information, mostly static */
262 	struct list_head list;
263 	struct sta_info *hnext;
264 	struct ieee80211_local *local;
265 	struct ieee80211_sub_if_data *sdata;
266 	struct ieee80211_key *gtk[NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS];
267 	struct ieee80211_key *ptk;
268 	struct rate_control_ref *rate_ctrl;
269 	void *rate_ctrl_priv;
270 	spinlock_t lock;
271 	spinlock_t flaglock;
272 
273 	struct work_struct drv_unblock_wk;
274 
275 	u16 listen_interval;
276 
277 	bool dead;
278 
279 	bool uploaded;
280 
281 	/*
282 	 * frequently updated, locked with own spinlock (flaglock),
283 	 * use the accessors defined below
284 	 */
285 	u32 flags;
286 
287 	/*
288 	 * STA powersave frame queues, no more than the internal
289 	 * locking required.
290 	 */
291 	struct sk_buff_head ps_tx_buf;
292 	struct sk_buff_head tx_filtered;
293 
294 	/* Updated from RX path only, no locking requirements */
295 	unsigned long rx_packets, rx_bytes;
296 	unsigned long wep_weak_iv_count;
297 	unsigned long last_rx;
298 	unsigned long num_duplicates;
299 	unsigned long rx_fragments;
300 	unsigned long rx_dropped;
301 	int last_signal;
302 	struct ewma avg_signal;
303 	__le16 last_seq_ctrl[NUM_RX_DATA_QUEUES];
304 
305 	/* Updated from TX status path only, no locking requirements */
306 	unsigned long tx_filtered_count;
307 	unsigned long tx_retry_failed, tx_retry_count;
308 	/* moving percentage of failed MSDUs */
309 	unsigned int fail_avg;
310 
311 	/* Updated from TX path only, no locking requirements */
312 	unsigned long tx_packets;
313 	unsigned long tx_bytes;
314 	unsigned long tx_fragments;
315 	struct ieee80211_tx_rate last_tx_rate;
316 	int last_rx_rate_idx;
317 	int last_rx_rate_flag;
318 	u16 tid_seq[IEEE80211_QOS_CTL_TID_MASK + 1];
319 
320 	/*
321 	 * Aggregation information, locked with lock.
322 	 */
323 	struct sta_ampdu_mlme ampdu_mlme;
324 	u8 timer_to_tid[STA_TID_NUM];
325 
326 #ifdef CONFIG_MAC80211_MESH
327 	/*
328 	 * Mesh peer link attributes
329 	 * TODO: move to a sub-structure that is referenced with pointer?
330 	 */
331 	__le16 llid;
332 	__le16 plid;
333 	__le16 reason;
334 	u8 plink_retries;
335 	bool ignore_plink_timer;
336 	bool plink_timer_was_running;
337 	enum plink_state plink_state;
338 	u32 plink_timeout;
339 	struct timer_list plink_timer;
340 #endif
341 
342 #ifdef CONFIG_MAC80211_DEBUGFS
343 	struct sta_info_debugfsdentries {
344 		struct dentry *dir;
345 		bool add_has_run;
346 	} debugfs;
347 #endif
348 
349 	unsigned int lost_packets;
350 
351 	/* keep last! */
352 	struct ieee80211_sta sta;
353 };
354 
sta_plink_state(struct sta_info * sta)355 static inline enum plink_state sta_plink_state(struct sta_info *sta)
356 {
357 #ifdef CONFIG_MAC80211_MESH
358 	return sta->plink_state;
359 #endif
360 	return PLINK_LISTEN;
361 }
362 
set_sta_flags(struct sta_info * sta,const u32 flags)363 static inline void set_sta_flags(struct sta_info *sta, const u32 flags)
364 {
365 	unsigned long irqfl;
366 
367 	spin_lock_irqsave(&sta->flaglock, irqfl);
368 	sta->flags |= flags;
369 	spin_unlock_irqrestore(&sta->flaglock, irqfl);
370 }
371 
clear_sta_flags(struct sta_info * sta,const u32 flags)372 static inline void clear_sta_flags(struct sta_info *sta, const u32 flags)
373 {
374 	unsigned long irqfl;
375 
376 	spin_lock_irqsave(&sta->flaglock, irqfl);
377 	sta->flags &= ~flags;
378 	spin_unlock_irqrestore(&sta->flaglock, irqfl);
379 }
380 
test_sta_flags(struct sta_info * sta,const u32 flags)381 static inline u32 test_sta_flags(struct sta_info *sta, const u32 flags)
382 {
383 	u32 ret;
384 	unsigned long irqfl;
385 
386 	spin_lock_irqsave(&sta->flaglock, irqfl);
387 	ret = sta->flags & flags;
388 	spin_unlock_irqrestore(&sta->flaglock, irqfl);
389 
390 	return ret;
391 }
392 
test_and_clear_sta_flags(struct sta_info * sta,const u32 flags)393 static inline u32 test_and_clear_sta_flags(struct sta_info *sta,
394 					   const u32 flags)
395 {
396 	u32 ret;
397 	unsigned long irqfl;
398 
399 	spin_lock_irqsave(&sta->flaglock, irqfl);
400 	ret = sta->flags & flags;
401 	sta->flags &= ~flags;
402 	spin_unlock_irqrestore(&sta->flaglock, irqfl);
403 
404 	return ret;
405 }
406 
get_sta_flags(struct sta_info * sta)407 static inline u32 get_sta_flags(struct sta_info *sta)
408 {
409 	u32 ret;
410 	unsigned long irqfl;
411 
412 	spin_lock_irqsave(&sta->flaglock, irqfl);
413 	ret = sta->flags;
414 	spin_unlock_irqrestore(&sta->flaglock, irqfl);
415 
416 	return ret;
417 }
418 
419 
420 
421 #define STA_HASH_SIZE 256
422 #define STA_HASH(sta) (sta[5])
423 
424 
425 /* Maximum number of frames to buffer per power saving station */
426 #define STA_MAX_TX_BUFFER 128
427 
428 /* Minimum buffered frame expiry time. If STA uses listen interval that is
429  * smaller than this value, the minimum value here is used instead. */
430 #define STA_TX_BUFFER_EXPIRE (10 * HZ)
431 
432 /* How often station data is cleaned up (e.g., expiration of buffered frames)
433  */
434 #define STA_INFO_CLEANUP_INTERVAL (10 * HZ)
435 
436 /*
437  * Get a STA info, must be under RCU read lock.
438  */
439 struct sta_info *sta_info_get(struct ieee80211_sub_if_data *sdata,
440 			      const u8 *addr);
441 
442 struct sta_info *sta_info_get_bss(struct ieee80211_sub_if_data *sdata,
443 				  const u8 *addr);
444 
445 static inline
for_each_sta_info_type_check(struct ieee80211_local * local,const u8 * addr,struct sta_info * sta,struct sta_info * nxt)446 void for_each_sta_info_type_check(struct ieee80211_local *local,
447 				  const u8 *addr,
448 				  struct sta_info *sta,
449 				  struct sta_info *nxt)
450 {
451 }
452 
453 #define for_each_sta_info(local, _addr, _sta, nxt) 			\
454 	for (	/* initialise loop */					\
455 		_sta = rcu_dereference(local->sta_hash[STA_HASH(_addr)]),\
456 		nxt = _sta ? rcu_dereference(_sta->hnext) : NULL;	\
457 		/* typecheck */						\
458 		for_each_sta_info_type_check(local, (_addr), _sta, nxt),\
459 		/* continue condition */				\
460 		_sta;							\
461 		/* advance loop */					\
462 		_sta = nxt,						\
463 		nxt = _sta ? rcu_dereference(_sta->hnext) : NULL	\
464 	     )								\
465 	/* compare address and run code only if it matches */		\
466 	if (memcmp(_sta->sta.addr, (_addr), ETH_ALEN) == 0)
467 
468 /*
469  * Get STA info by index, BROKEN!
470  */
471 struct sta_info *sta_info_get_by_idx(struct ieee80211_sub_if_data *sdata,
472 				     int idx);
473 /*
474  * Create a new STA info, caller owns returned structure
475  * until sta_info_insert().
476  */
477 struct sta_info *sta_info_alloc(struct ieee80211_sub_if_data *sdata,
478 				u8 *addr, gfp_t gfp);
479 /*
480  * Insert STA info into hash table/list, returns zero or a
481  * -EEXIST if (if the same MAC address is already present).
482  *
483  * Calling the non-rcu version makes the caller relinquish,
484  * the _rcu version calls read_lock_rcu() and must be called
485  * without it held.
486  */
487 int sta_info_insert(struct sta_info *sta);
488 int sta_info_insert_rcu(struct sta_info *sta) __acquires(RCU);
489 int sta_info_insert_atomic(struct sta_info *sta);
490 
491 int sta_info_destroy_addr(struct ieee80211_sub_if_data *sdata,
492 			  const u8 *addr);
493 int sta_info_destroy_addr_bss(struct ieee80211_sub_if_data *sdata,
494 			      const u8 *addr);
495 
496 void sta_info_set_tim_bit(struct sta_info *sta);
497 void sta_info_clear_tim_bit(struct sta_info *sta);
498 
499 void sta_info_init(struct ieee80211_local *local);
500 int sta_info_start(struct ieee80211_local *local);
501 void sta_info_stop(struct ieee80211_local *local);
502 int sta_info_flush(struct ieee80211_local *local,
503 		   struct ieee80211_sub_if_data *sdata);
504 void ieee80211_sta_expire(struct ieee80211_sub_if_data *sdata,
505 			  unsigned long exp_time);
506 
507 void ieee80211_sta_ps_deliver_wakeup(struct sta_info *sta);
508 void ieee80211_sta_ps_deliver_poll_response(struct sta_info *sta);
509 
510 #endif /* STA_INFO_H */
511