Merge tag 'mac80211-next-for-net-next-2020-02-14' of git://git.kernel.org/pub/scm...
[platform/kernel/linux-rpi.git] / net / mac80211 / agg-rx.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * HT handling
4  *
5  * Copyright 2003, Jouni Malinen <jkmaline@cc.hut.fi>
6  * Copyright 2002-2005, Instant802 Networks, Inc.
7  * Copyright 2005-2006, Devicescape Software, Inc.
8  * Copyright 2006-2007  Jiri Benc <jbenc@suse.cz>
9  * Copyright 2007, Michael Wu <flamingice@sourmilk.net>
10  * Copyright 2007-2010, Intel Corporation
11  * Copyright(c) 2015-2017 Intel Deutschland GmbH
12  * Copyright (C) 2018        Intel Corporation
13  */
14
15 /**
16  * DOC: RX A-MPDU aggregation
17  *
18  * Aggregation on the RX side requires only implementing the
19  * @ampdu_action callback that is invoked to start/stop any
20  * block-ack sessions for RX aggregation.
21  *
22  * When RX aggregation is started by the peer, the driver is
23  * notified via @ampdu_action function, with the
24  * %IEEE80211_AMPDU_RX_START action, and may reject the request
25  * in which case a negative response is sent to the peer, if it
26  * accepts it a positive response is sent.
27  *
28  * While the session is active, the device/driver are required
29  * to de-aggregate frames and pass them up one by one to mac80211,
30  * which will handle the reorder buffer.
31  *
32  * When the aggregation session is stopped again by the peer or
33  * ourselves, the driver's @ampdu_action function will be called
34  * with the action %IEEE80211_AMPDU_RX_STOP. In this case, the
35  * call must not fail.
36  */
37
38 #include <linux/ieee80211.h>
39 #include <linux/slab.h>
40 #include <linux/export.h>
41 #include <net/mac80211.h>
42 #include "ieee80211_i.h"
43 #include "driver-ops.h"
44
45 static void ieee80211_free_tid_rx(struct rcu_head *h)
46 {
47         struct tid_ampdu_rx *tid_rx =
48                 container_of(h, struct tid_ampdu_rx, rcu_head);
49         int i;
50
51         for (i = 0; i < tid_rx->buf_size; i++)
52                 __skb_queue_purge(&tid_rx->reorder_buf[i]);
53         kfree(tid_rx->reorder_buf);
54         kfree(tid_rx->reorder_time);
55         kfree(tid_rx);
56 }
57
58 void ___ieee80211_stop_rx_ba_session(struct sta_info *sta, u16 tid,
59                                      u16 initiator, u16 reason, bool tx)
60 {
61         struct ieee80211_local *local = sta->local;
62         struct tid_ampdu_rx *tid_rx;
63         struct ieee80211_ampdu_params params = {
64                 .sta = &sta->sta,
65                 .action = IEEE80211_AMPDU_RX_STOP,
66                 .tid = tid,
67                 .amsdu = false,
68                 .timeout = 0,
69                 .ssn = 0,
70         };
71
72         lockdep_assert_held(&sta->ampdu_mlme.mtx);
73
74         tid_rx = rcu_dereference_protected(sta->ampdu_mlme.tid_rx[tid],
75                                         lockdep_is_held(&sta->ampdu_mlme.mtx));
76
77         if (!test_bit(tid, sta->ampdu_mlme.agg_session_valid))
78                 return;
79
80         RCU_INIT_POINTER(sta->ampdu_mlme.tid_rx[tid], NULL);
81         __clear_bit(tid, sta->ampdu_mlme.agg_session_valid);
82
83         ht_dbg(sta->sdata,
84                "Rx BA session stop requested for %pM tid %u %s reason: %d\n",
85                sta->sta.addr, tid,
86                initiator == WLAN_BACK_RECIPIENT ? "recipient" : "initiator",
87                (int)reason);
88
89         if (drv_ampdu_action(local, sta->sdata, &params))
90                 sdata_info(sta->sdata,
91                            "HW problem - can not stop rx aggregation for %pM tid %d\n",
92                            sta->sta.addr, tid);
93
94         /* check if this is a self generated aggregation halt */
95         if (initiator == WLAN_BACK_RECIPIENT && tx)
96                 ieee80211_send_delba(sta->sdata, sta->sta.addr,
97                                      tid, WLAN_BACK_RECIPIENT, reason);
98
99         /*
100          * return here in case tid_rx is not assigned - which will happen if
101          * IEEE80211_HW_SUPPORTS_REORDERING_BUFFER is set.
102          */
103         if (!tid_rx)
104                 return;
105
106         del_timer_sync(&tid_rx->session_timer);
107
108         /* make sure ieee80211_sta_reorder_release() doesn't re-arm the timer */
109         spin_lock_bh(&tid_rx->reorder_lock);
110         tid_rx->removed = true;
111         spin_unlock_bh(&tid_rx->reorder_lock);
112         del_timer_sync(&tid_rx->reorder_timer);
113
114         call_rcu(&tid_rx->rcu_head, ieee80211_free_tid_rx);
115 }
116
117 void __ieee80211_stop_rx_ba_session(struct sta_info *sta, u16 tid,
118                                     u16 initiator, u16 reason, bool tx)
119 {
120         mutex_lock(&sta->ampdu_mlme.mtx);
121         ___ieee80211_stop_rx_ba_session(sta, tid, initiator, reason, tx);
122         mutex_unlock(&sta->ampdu_mlme.mtx);
123 }
124
125 void ieee80211_stop_rx_ba_session(struct ieee80211_vif *vif, u16 ba_rx_bitmap,
126                                   const u8 *addr)
127 {
128         struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
129         struct sta_info *sta;
130         int i;
131
132         rcu_read_lock();
133         sta = sta_info_get_bss(sdata, addr);
134         if (!sta) {
135                 rcu_read_unlock();
136                 return;
137         }
138
139         for (i = 0; i < IEEE80211_NUM_TIDS; i++)
140                 if (ba_rx_bitmap & BIT(i))
141                         set_bit(i, sta->ampdu_mlme.tid_rx_stop_requested);
142
143         ieee80211_queue_work(&sta->local->hw, &sta->ampdu_mlme.work);
144         rcu_read_unlock();
145 }
146 EXPORT_SYMBOL(ieee80211_stop_rx_ba_session);
147
148 /*
149  * After accepting the AddBA Request we activated a timer,
150  * resetting it after each frame that arrives from the originator.
151  */
152 static void sta_rx_agg_session_timer_expired(struct timer_list *t)
153 {
154         struct tid_ampdu_rx *tid_rx = from_timer(tid_rx, t, session_timer);
155         struct sta_info *sta = tid_rx->sta;
156         u8 tid = tid_rx->tid;
157         unsigned long timeout;
158
159         timeout = tid_rx->last_rx + TU_TO_JIFFIES(tid_rx->timeout);
160         if (time_is_after_jiffies(timeout)) {
161                 mod_timer(&tid_rx->session_timer, timeout);
162                 return;
163         }
164
165         ht_dbg(sta->sdata, "RX session timer expired on %pM tid %d\n",
166                sta->sta.addr, tid);
167
168         set_bit(tid, sta->ampdu_mlme.tid_rx_timer_expired);
169         ieee80211_queue_work(&sta->local->hw, &sta->ampdu_mlme.work);
170 }
171
172 static void sta_rx_agg_reorder_timer_expired(struct timer_list *t)
173 {
174         struct tid_ampdu_rx *tid_rx = from_timer(tid_rx, t, reorder_timer);
175
176         rcu_read_lock();
177         ieee80211_release_reorder_timeout(tid_rx->sta, tid_rx->tid);
178         rcu_read_unlock();
179 }
180
181 static void ieee80211_add_addbaext(struct ieee80211_sub_if_data *sdata,
182                                    struct sk_buff *skb,
183                                    const struct ieee80211_addba_ext_ie *req)
184 {
185         struct ieee80211_supported_band *sband;
186         struct ieee80211_addba_ext_ie *resp;
187         const struct ieee80211_sta_he_cap *he_cap;
188         u8 frag_level, cap_frag_level;
189         u8 *pos;
190
191         sband = ieee80211_get_sband(sdata);
192         if (!sband)
193                 return;
194         he_cap = ieee80211_get_he_iftype_cap(sband, sdata->vif.type);
195         if (!he_cap)
196                 return;
197
198         pos = skb_put_zero(skb, 2 + sizeof(struct ieee80211_addba_ext_ie));
199         *pos++ = WLAN_EID_ADDBA_EXT;
200         *pos++ = sizeof(struct ieee80211_addba_ext_ie);
201         resp = (struct ieee80211_addba_ext_ie *)pos;
202         resp->data = req->data & IEEE80211_ADDBA_EXT_NO_FRAG;
203
204         frag_level = u32_get_bits(req->data,
205                                   IEEE80211_ADDBA_EXT_FRAG_LEVEL_MASK);
206         cap_frag_level = u32_get_bits(he_cap->he_cap_elem.mac_cap_info[0],
207                                       IEEE80211_HE_MAC_CAP0_DYNAMIC_FRAG_MASK);
208         if (frag_level > cap_frag_level)
209                 frag_level = cap_frag_level;
210         resp->data |= u8_encode_bits(frag_level,
211                                      IEEE80211_ADDBA_EXT_FRAG_LEVEL_MASK);
212 }
213
214 static void ieee80211_send_addba_resp(struct sta_info *sta, u8 *da, u16 tid,
215                                       u8 dialog_token, u16 status, u16 policy,
216                                       u16 buf_size, u16 timeout,
217                                       const struct ieee80211_addba_ext_ie *addbaext)
218 {
219         struct ieee80211_sub_if_data *sdata = sta->sdata;
220         struct ieee80211_local *local = sdata->local;
221         struct sk_buff *skb;
222         struct ieee80211_mgmt *mgmt;
223         bool amsdu = ieee80211_hw_check(&local->hw, SUPPORTS_AMSDU_IN_AMPDU);
224         u16 capab;
225
226         skb = dev_alloc_skb(sizeof(*mgmt) +
227                     2 + sizeof(struct ieee80211_addba_ext_ie) +
228                     local->hw.extra_tx_headroom);
229         if (!skb)
230                 return;
231
232         skb_reserve(skb, local->hw.extra_tx_headroom);
233         mgmt = skb_put_zero(skb, 24);
234         memcpy(mgmt->da, da, ETH_ALEN);
235         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
236         if (sdata->vif.type == NL80211_IFTYPE_AP ||
237             sdata->vif.type == NL80211_IFTYPE_AP_VLAN ||
238             sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
239                 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
240         else if (sdata->vif.type == NL80211_IFTYPE_STATION)
241                 memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN);
242         else if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
243                 memcpy(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN);
244
245         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
246                                           IEEE80211_STYPE_ACTION);
247
248         skb_put(skb, 1 + sizeof(mgmt->u.action.u.addba_resp));
249         mgmt->u.action.category = WLAN_CATEGORY_BACK;
250         mgmt->u.action.u.addba_resp.action_code = WLAN_ACTION_ADDBA_RESP;
251         mgmt->u.action.u.addba_resp.dialog_token = dialog_token;
252
253         capab = (u16)(amsdu << 0);      /* bit 0 A-MSDU support */
254         capab |= (u16)(policy << 1);    /* bit 1 aggregation policy */
255         capab |= (u16)(tid << 2);       /* bit 5:2 TID number */
256         capab |= (u16)(buf_size << 6);  /* bit 15:6 max size of aggregation */
257
258         mgmt->u.action.u.addba_resp.capab = cpu_to_le16(capab);
259         mgmt->u.action.u.addba_resp.timeout = cpu_to_le16(timeout);
260         mgmt->u.action.u.addba_resp.status = cpu_to_le16(status);
261
262         if (sta->sta.he_cap.has_he && addbaext)
263                 ieee80211_add_addbaext(sdata, skb, addbaext);
264
265         ieee80211_tx_skb(sdata, skb);
266 }
267
268 void ___ieee80211_start_rx_ba_session(struct sta_info *sta,
269                                       u8 dialog_token, u16 timeout,
270                                       u16 start_seq_num, u16 ba_policy, u16 tid,
271                                       u16 buf_size, bool tx, bool auto_seq,
272                                       const struct ieee80211_addba_ext_ie *addbaext)
273 {
274         struct ieee80211_local *local = sta->sdata->local;
275         struct tid_ampdu_rx *tid_agg_rx;
276         struct ieee80211_ampdu_params params = {
277                 .sta = &sta->sta,
278                 .action = IEEE80211_AMPDU_RX_START,
279                 .tid = tid,
280                 .amsdu = false,
281                 .timeout = timeout,
282                 .ssn = start_seq_num,
283         };
284         int i, ret = -EOPNOTSUPP;
285         u16 status = WLAN_STATUS_REQUEST_DECLINED;
286         u16 max_buf_size;
287
288         if (tid >= IEEE80211_FIRST_TSPEC_TSID) {
289                 ht_dbg(sta->sdata,
290                        "STA %pM requests BA session on unsupported tid %d\n",
291                        sta->sta.addr, tid);
292                 goto end;
293         }
294
295         if (!sta->sta.ht_cap.ht_supported) {
296                 ht_dbg(sta->sdata,
297                        "STA %pM erroneously requests BA session on tid %d w/o QoS\n",
298                        sta->sta.addr, tid);
299                 /* send a response anyway, it's an error case if we get here */
300                 goto end;
301         }
302
303         if (test_sta_flag(sta, WLAN_STA_BLOCK_BA)) {
304                 ht_dbg(sta->sdata,
305                        "Suspend in progress - Denying ADDBA request (%pM tid %d)\n",
306                        sta->sta.addr, tid);
307                 goto end;
308         }
309
310         if (sta->sta.he_cap.has_he)
311                 max_buf_size = IEEE80211_MAX_AMPDU_BUF;
312         else
313                 max_buf_size = IEEE80211_MAX_AMPDU_BUF_HT;
314
315         /* sanity check for incoming parameters:
316          * check if configuration can support the BA policy
317          * and if buffer size does not exceeds max value */
318         /* XXX: check own ht delayed BA capability?? */
319         if (((ba_policy != 1) &&
320              (!(sta->sta.ht_cap.cap & IEEE80211_HT_CAP_DELAY_BA))) ||
321             (buf_size > max_buf_size)) {
322                 status = WLAN_STATUS_INVALID_QOS_PARAM;
323                 ht_dbg_ratelimited(sta->sdata,
324                                    "AddBA Req with bad params from %pM on tid %u. policy %d, buffer size %d\n",
325                                    sta->sta.addr, tid, ba_policy, buf_size);
326                 goto end;
327         }
328         /* determine default buffer size */
329         if (buf_size == 0)
330                 buf_size = max_buf_size;
331
332         /* make sure the size doesn't exceed the maximum supported by the hw */
333         if (buf_size > sta->sta.max_rx_aggregation_subframes)
334                 buf_size = sta->sta.max_rx_aggregation_subframes;
335         params.buf_size = buf_size;
336
337         ht_dbg(sta->sdata, "AddBA Req buf_size=%d for %pM\n",
338                buf_size, sta->sta.addr);
339
340         /* examine state machine */
341         lockdep_assert_held(&sta->ampdu_mlme.mtx);
342
343         if (test_bit(tid, sta->ampdu_mlme.agg_session_valid)) {
344                 if (sta->ampdu_mlme.tid_rx_token[tid] == dialog_token) {
345                         struct tid_ampdu_rx *tid_rx;
346
347                         ht_dbg_ratelimited(sta->sdata,
348                                            "updated AddBA Req from %pM on tid %u\n",
349                                            sta->sta.addr, tid);
350                         /* We have no API to update the timeout value in the
351                          * driver so reject the timeout update if the timeout
352                          * changed. If if did not change, i.e., no real update,
353                          * just reply with success.
354                          */
355                         rcu_read_lock();
356                         tid_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
357                         if (tid_rx && tid_rx->timeout == timeout)
358                                 status = WLAN_STATUS_SUCCESS;
359                         else
360                                 status = WLAN_STATUS_REQUEST_DECLINED;
361                         rcu_read_unlock();
362                         goto end;
363                 }
364
365                 ht_dbg_ratelimited(sta->sdata,
366                                    "unexpected AddBA Req from %pM on tid %u\n",
367                                    sta->sta.addr, tid);
368
369                 /* delete existing Rx BA session on the same tid */
370                 ___ieee80211_stop_rx_ba_session(sta, tid, WLAN_BACK_RECIPIENT,
371                                                 WLAN_STATUS_UNSPECIFIED_QOS,
372                                                 false);
373         }
374
375         if (ieee80211_hw_check(&local->hw, SUPPORTS_REORDERING_BUFFER)) {
376                 ret = drv_ampdu_action(local, sta->sdata, &params);
377                 ht_dbg(sta->sdata,
378                        "Rx A-MPDU request on %pM tid %d result %d\n",
379                        sta->sta.addr, tid, ret);
380                 if (!ret)
381                         status = WLAN_STATUS_SUCCESS;
382                 goto end;
383         }
384
385         /* prepare A-MPDU MLME for Rx aggregation */
386         tid_agg_rx = kzalloc(sizeof(*tid_agg_rx), GFP_KERNEL);
387         if (!tid_agg_rx)
388                 goto end;
389
390         spin_lock_init(&tid_agg_rx->reorder_lock);
391
392         /* rx timer */
393         timer_setup(&tid_agg_rx->session_timer,
394                     sta_rx_agg_session_timer_expired, TIMER_DEFERRABLE);
395
396         /* rx reorder timer */
397         timer_setup(&tid_agg_rx->reorder_timer,
398                     sta_rx_agg_reorder_timer_expired, 0);
399
400         /* prepare reordering buffer */
401         tid_agg_rx->reorder_buf =
402                 kcalloc(buf_size, sizeof(struct sk_buff_head), GFP_KERNEL);
403         tid_agg_rx->reorder_time =
404                 kcalloc(buf_size, sizeof(unsigned long), GFP_KERNEL);
405         if (!tid_agg_rx->reorder_buf || !tid_agg_rx->reorder_time) {
406                 kfree(tid_agg_rx->reorder_buf);
407                 kfree(tid_agg_rx->reorder_time);
408                 kfree(tid_agg_rx);
409                 goto end;
410         }
411
412         for (i = 0; i < buf_size; i++)
413                 __skb_queue_head_init(&tid_agg_rx->reorder_buf[i]);
414
415         ret = drv_ampdu_action(local, sta->sdata, &params);
416         ht_dbg(sta->sdata, "Rx A-MPDU request on %pM tid %d result %d\n",
417                sta->sta.addr, tid, ret);
418         if (ret) {
419                 kfree(tid_agg_rx->reorder_buf);
420                 kfree(tid_agg_rx->reorder_time);
421                 kfree(tid_agg_rx);
422                 goto end;
423         }
424
425         /* update data */
426         tid_agg_rx->ssn = start_seq_num;
427         tid_agg_rx->head_seq_num = start_seq_num;
428         tid_agg_rx->buf_size = buf_size;
429         tid_agg_rx->timeout = timeout;
430         tid_agg_rx->stored_mpdu_num = 0;
431         tid_agg_rx->auto_seq = auto_seq;
432         tid_agg_rx->started = false;
433         tid_agg_rx->reorder_buf_filtered = 0;
434         tid_agg_rx->tid = tid;
435         tid_agg_rx->sta = sta;
436         status = WLAN_STATUS_SUCCESS;
437
438         /* activate it for RX */
439         rcu_assign_pointer(sta->ampdu_mlme.tid_rx[tid], tid_agg_rx);
440
441         if (timeout) {
442                 mod_timer(&tid_agg_rx->session_timer, TU_TO_EXP_TIME(timeout));
443                 tid_agg_rx->last_rx = jiffies;
444         }
445
446 end:
447         if (status == WLAN_STATUS_SUCCESS) {
448                 __set_bit(tid, sta->ampdu_mlme.agg_session_valid);
449                 __clear_bit(tid, sta->ampdu_mlme.unexpected_agg);
450                 sta->ampdu_mlme.tid_rx_token[tid] = dialog_token;
451         }
452
453         if (tx)
454                 ieee80211_send_addba_resp(sta, sta->sta.addr, tid,
455                                           dialog_token, status, 1, buf_size,
456                                           timeout, addbaext);
457 }
458
459 static void __ieee80211_start_rx_ba_session(struct sta_info *sta,
460                                             u8 dialog_token, u16 timeout,
461                                             u16 start_seq_num, u16 ba_policy,
462                                             u16 tid, u16 buf_size, bool tx,
463                                             bool auto_seq,
464                                             const struct ieee80211_addba_ext_ie *addbaext)
465 {
466         mutex_lock(&sta->ampdu_mlme.mtx);
467         ___ieee80211_start_rx_ba_session(sta, dialog_token, timeout,
468                                          start_seq_num, ba_policy, tid,
469                                          buf_size, tx, auto_seq, addbaext);
470         mutex_unlock(&sta->ampdu_mlme.mtx);
471 }
472
473 void ieee80211_process_addba_request(struct ieee80211_local *local,
474                                      struct sta_info *sta,
475                                      struct ieee80211_mgmt *mgmt,
476                                      size_t len)
477 {
478         u16 capab, tid, timeout, ba_policy, buf_size, start_seq_num;
479         struct ieee802_11_elems elems = { 0 };
480         u8 dialog_token;
481         int ies_len;
482
483         /* extract session parameters from addba request frame */
484         dialog_token = mgmt->u.action.u.addba_req.dialog_token;
485         timeout = le16_to_cpu(mgmt->u.action.u.addba_req.timeout);
486         start_seq_num =
487                 le16_to_cpu(mgmt->u.action.u.addba_req.start_seq_num) >> 4;
488
489         capab = le16_to_cpu(mgmt->u.action.u.addba_req.capab);
490         ba_policy = (capab & IEEE80211_ADDBA_PARAM_POLICY_MASK) >> 1;
491         tid = (capab & IEEE80211_ADDBA_PARAM_TID_MASK) >> 2;
492         buf_size = (capab & IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK) >> 6;
493
494         ies_len = len - offsetof(struct ieee80211_mgmt,
495                                  u.action.u.addba_req.variable);
496         if (ies_len) {
497                 ieee802_11_parse_elems(mgmt->u.action.u.addba_req.variable,
498                                 ies_len, true, &elems, mgmt->bssid, NULL);
499                 if (elems.parse_error)
500                         return;
501         }
502
503         __ieee80211_start_rx_ba_session(sta, dialog_token, timeout,
504                                         start_seq_num, ba_policy, tid,
505                                         buf_size, true, false,
506                                         elems.addba_ext_ie);
507 }
508
509 void ieee80211_manage_rx_ba_offl(struct ieee80211_vif *vif,
510                                  const u8 *addr, unsigned int tid)
511 {
512         struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
513         struct ieee80211_local *local = sdata->local;
514         struct sta_info *sta;
515
516         rcu_read_lock();
517         sta = sta_info_get_bss(sdata, addr);
518         if (!sta)
519                 goto unlock;
520
521         set_bit(tid, sta->ampdu_mlme.tid_rx_manage_offl);
522         ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work);
523  unlock:
524         rcu_read_unlock();
525 }
526 EXPORT_SYMBOL(ieee80211_manage_rx_ba_offl);
527
528 void ieee80211_rx_ba_timer_expired(struct ieee80211_vif *vif,
529                                    const u8 *addr, unsigned int tid)
530 {
531         struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
532         struct ieee80211_local *local = sdata->local;
533         struct sta_info *sta;
534
535         rcu_read_lock();
536         sta = sta_info_get_bss(sdata, addr);
537         if (!sta)
538                 goto unlock;
539
540         set_bit(tid, sta->ampdu_mlme.tid_rx_timer_expired);
541         ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work);
542
543  unlock:
544         rcu_read_unlock();
545 }
546 EXPORT_SYMBOL(ieee80211_rx_ba_timer_expired);