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) 2018-2020 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, ¶ms)) 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 sta->sdata->vif.bss_conf.chandef.chan->band != NL80211_BAND_6GHZ) { 297 ht_dbg(sta->sdata, 298 "STA %pM erroneously requests BA session on tid %d w/o QoS\n", 299 sta->sta.addr, tid); 300 /* send a response anyway, it's an error case if we get here */ 301 goto end; 302 } 303 304 if (test_sta_flag(sta, WLAN_STA_BLOCK_BA)) { 305 ht_dbg(sta->sdata, 306 "Suspend in progress - Denying ADDBA request (%pM tid %d)\n", 307 sta->sta.addr, tid); 308 goto end; 309 } 310 311 if (sta->sta.he_cap.has_he) 312 max_buf_size = IEEE80211_MAX_AMPDU_BUF; 313 else 314 max_buf_size = IEEE80211_MAX_AMPDU_BUF_HT; 315 316 /* sanity check for incoming parameters: 317 * check if configuration can support the BA policy 318 * and if buffer size does not exceeds max value */ 319 /* XXX: check own ht delayed BA capability?? */ 320 if (((ba_policy != 1) && 321 (!(sta->sta.ht_cap.cap & IEEE80211_HT_CAP_DELAY_BA))) || 322 (buf_size > max_buf_size)) { 323 status = WLAN_STATUS_INVALID_QOS_PARAM; 324 ht_dbg_ratelimited(sta->sdata, 325 "AddBA Req with bad params from %pM on tid %u. policy %d, buffer size %d\n", 326 sta->sta.addr, tid, ba_policy, buf_size); 327 goto end; 328 } 329 /* determine default buffer size */ 330 if (buf_size == 0) 331 buf_size = max_buf_size; 332 333 /* make sure the size doesn't exceed the maximum supported by the hw */ 334 if (buf_size > sta->sta.max_rx_aggregation_subframes) 335 buf_size = sta->sta.max_rx_aggregation_subframes; 336 params.buf_size = buf_size; 337 338 ht_dbg(sta->sdata, "AddBA Req buf_size=%d for %pM\n", 339 buf_size, sta->sta.addr); 340 341 /* examine state machine */ 342 lockdep_assert_held(&sta->ampdu_mlme.mtx); 343 344 if (test_bit(tid, sta->ampdu_mlme.agg_session_valid)) { 345 if (sta->ampdu_mlme.tid_rx_token[tid] == dialog_token) { 346 struct tid_ampdu_rx *tid_rx; 347 348 ht_dbg_ratelimited(sta->sdata, 349 "updated AddBA Req from %pM on tid %u\n", 350 sta->sta.addr, tid); 351 /* We have no API to update the timeout value in the 352 * driver so reject the timeout update if the timeout 353 * changed. If if did not change, i.e., no real update, 354 * just reply with success. 355 */ 356 rcu_read_lock(); 357 tid_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]); 358 if (tid_rx && tid_rx->timeout == timeout) 359 status = WLAN_STATUS_SUCCESS; 360 else 361 status = WLAN_STATUS_REQUEST_DECLINED; 362 rcu_read_unlock(); 363 goto end; 364 } 365 366 ht_dbg_ratelimited(sta->sdata, 367 "unexpected AddBA Req from %pM on tid %u\n", 368 sta->sta.addr, tid); 369 370 /* delete existing Rx BA session on the same tid */ 371 ___ieee80211_stop_rx_ba_session(sta, tid, WLAN_BACK_RECIPIENT, 372 WLAN_STATUS_UNSPECIFIED_QOS, 373 false); 374 } 375 376 if (ieee80211_hw_check(&local->hw, SUPPORTS_REORDERING_BUFFER)) { 377 ret = drv_ampdu_action(local, sta->sdata, ¶ms); 378 ht_dbg(sta->sdata, 379 "Rx A-MPDU request on %pM tid %d result %d\n", 380 sta->sta.addr, tid, ret); 381 if (!ret) 382 status = WLAN_STATUS_SUCCESS; 383 goto end; 384 } 385 386 /* prepare A-MPDU MLME for Rx aggregation */ 387 tid_agg_rx = kzalloc(sizeof(*tid_agg_rx), GFP_KERNEL); 388 if (!tid_agg_rx) 389 goto end; 390 391 spin_lock_init(&tid_agg_rx->reorder_lock); 392 393 /* rx timer */ 394 timer_setup(&tid_agg_rx->session_timer, 395 sta_rx_agg_session_timer_expired, TIMER_DEFERRABLE); 396 397 /* rx reorder timer */ 398 timer_setup(&tid_agg_rx->reorder_timer, 399 sta_rx_agg_reorder_timer_expired, 0); 400 401 /* prepare reordering buffer */ 402 tid_agg_rx->reorder_buf = 403 kcalloc(buf_size, sizeof(struct sk_buff_head), GFP_KERNEL); 404 tid_agg_rx->reorder_time = 405 kcalloc(buf_size, sizeof(unsigned long), GFP_KERNEL); 406 if (!tid_agg_rx->reorder_buf || !tid_agg_rx->reorder_time) { 407 kfree(tid_agg_rx->reorder_buf); 408 kfree(tid_agg_rx->reorder_time); 409 kfree(tid_agg_rx); 410 goto end; 411 } 412 413 for (i = 0; i < buf_size; i++) 414 __skb_queue_head_init(&tid_agg_rx->reorder_buf[i]); 415 416 ret = drv_ampdu_action(local, sta->sdata, ¶ms); 417 ht_dbg(sta->sdata, "Rx A-MPDU request on %pM tid %d result %d\n", 418 sta->sta.addr, tid, ret); 419 if (ret) { 420 kfree(tid_agg_rx->reorder_buf); 421 kfree(tid_agg_rx->reorder_time); 422 kfree(tid_agg_rx); 423 goto end; 424 } 425 426 /* update data */ 427 tid_agg_rx->ssn = start_seq_num; 428 tid_agg_rx->head_seq_num = start_seq_num; 429 tid_agg_rx->buf_size = buf_size; 430 tid_agg_rx->timeout = timeout; 431 tid_agg_rx->stored_mpdu_num = 0; 432 tid_agg_rx->auto_seq = auto_seq; 433 tid_agg_rx->started = false; 434 tid_agg_rx->reorder_buf_filtered = 0; 435 tid_agg_rx->tid = tid; 436 tid_agg_rx->sta = sta; 437 status = WLAN_STATUS_SUCCESS; 438 439 /* activate it for RX */ 440 rcu_assign_pointer(sta->ampdu_mlme.tid_rx[tid], tid_agg_rx); 441 442 if (timeout) { 443 mod_timer(&tid_agg_rx->session_timer, TU_TO_EXP_TIME(timeout)); 444 tid_agg_rx->last_rx = jiffies; 445 } 446 447 end: 448 if (status == WLAN_STATUS_SUCCESS) { 449 __set_bit(tid, sta->ampdu_mlme.agg_session_valid); 450 __clear_bit(tid, sta->ampdu_mlme.unexpected_agg); 451 sta->ampdu_mlme.tid_rx_token[tid] = dialog_token; 452 } 453 454 if (tx) 455 ieee80211_send_addba_resp(sta, sta->sta.addr, tid, 456 dialog_token, status, 1, buf_size, 457 timeout, addbaext); 458 } 459 460 static void __ieee80211_start_rx_ba_session(struct sta_info *sta, 461 u8 dialog_token, u16 timeout, 462 u16 start_seq_num, u16 ba_policy, 463 u16 tid, u16 buf_size, bool tx, 464 bool auto_seq, 465 const struct ieee80211_addba_ext_ie *addbaext) 466 { 467 mutex_lock(&sta->ampdu_mlme.mtx); 468 ___ieee80211_start_rx_ba_session(sta, dialog_token, timeout, 469 start_seq_num, ba_policy, tid, 470 buf_size, tx, auto_seq, addbaext); 471 mutex_unlock(&sta->ampdu_mlme.mtx); 472 } 473 474 void ieee80211_process_addba_request(struct ieee80211_local *local, 475 struct sta_info *sta, 476 struct ieee80211_mgmt *mgmt, 477 size_t len) 478 { 479 u16 capab, tid, timeout, ba_policy, buf_size, start_seq_num; 480 struct ieee802_11_elems elems = { }; 481 u8 dialog_token; 482 int ies_len; 483 484 /* extract session parameters from addba request frame */ 485 dialog_token = mgmt->u.action.u.addba_req.dialog_token; 486 timeout = le16_to_cpu(mgmt->u.action.u.addba_req.timeout); 487 start_seq_num = 488 le16_to_cpu(mgmt->u.action.u.addba_req.start_seq_num) >> 4; 489 490 capab = le16_to_cpu(mgmt->u.action.u.addba_req.capab); 491 ba_policy = (capab & IEEE80211_ADDBA_PARAM_POLICY_MASK) >> 1; 492 tid = (capab & IEEE80211_ADDBA_PARAM_TID_MASK) >> 2; 493 buf_size = (capab & IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK) >> 6; 494 495 ies_len = len - offsetof(struct ieee80211_mgmt, 496 u.action.u.addba_req.variable); 497 if (ies_len) { 498 ieee802_11_parse_elems(mgmt->u.action.u.addba_req.variable, 499 ies_len, true, &elems, mgmt->bssid, NULL); 500 if (elems.parse_error) 501 return; 502 } 503 504 __ieee80211_start_rx_ba_session(sta, dialog_token, timeout, 505 start_seq_num, ba_policy, tid, 506 buf_size, true, false, 507 elems.addba_ext_ie); 508 } 509 510 void ieee80211_manage_rx_ba_offl(struct ieee80211_vif *vif, 511 const u8 *addr, unsigned int tid) 512 { 513 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif); 514 struct ieee80211_local *local = sdata->local; 515 struct sta_info *sta; 516 517 rcu_read_lock(); 518 sta = sta_info_get_bss(sdata, addr); 519 if (!sta) 520 goto unlock; 521 522 set_bit(tid, sta->ampdu_mlme.tid_rx_manage_offl); 523 ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work); 524 unlock: 525 rcu_read_unlock(); 526 } 527 EXPORT_SYMBOL(ieee80211_manage_rx_ba_offl); 528 529 void ieee80211_rx_ba_timer_expired(struct ieee80211_vif *vif, 530 const u8 *addr, unsigned int tid) 531 { 532 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif); 533 struct ieee80211_local *local = sdata->local; 534 struct sta_info *sta; 535 536 rcu_read_lock(); 537 sta = sta_info_get_bss(sdata, addr); 538 if (!sta) 539 goto unlock; 540 541 set_bit(tid, sta->ampdu_mlme.tid_rx_timer_expired); 542 ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work); 543 544 unlock: 545 rcu_read_unlock(); 546 } 547 EXPORT_SYMBOL(ieee80211_rx_ba_timer_expired); 548