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) 2018-2021 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, 195 ieee80211_vif_type_p2p(&sdata->vif)); 196 if (!he_cap) 197 return; 198 199 pos = skb_put_zero(skb, 2 + sizeof(struct ieee80211_addba_ext_ie)); 200 *pos++ = WLAN_EID_ADDBA_EXT; 201 *pos++ = sizeof(struct ieee80211_addba_ext_ie); 202 resp = (struct ieee80211_addba_ext_ie *)pos; 203 resp->data = req->data & IEEE80211_ADDBA_EXT_NO_FRAG; 204 205 frag_level = u32_get_bits(req->data, 206 IEEE80211_ADDBA_EXT_FRAG_LEVEL_MASK); 207 cap_frag_level = u32_get_bits(he_cap->he_cap_elem.mac_cap_info[0], 208 IEEE80211_HE_MAC_CAP0_DYNAMIC_FRAG_MASK); 209 if (frag_level > cap_frag_level) 210 frag_level = cap_frag_level; 211 resp->data |= u8_encode_bits(frag_level, 212 IEEE80211_ADDBA_EXT_FRAG_LEVEL_MASK); 213 } 214 215 static void ieee80211_send_addba_resp(struct sta_info *sta, u8 *da, u16 tid, 216 u8 dialog_token, u16 status, u16 policy, 217 u16 buf_size, u16 timeout, 218 const struct ieee80211_addba_ext_ie *addbaext) 219 { 220 struct ieee80211_sub_if_data *sdata = sta->sdata; 221 struct ieee80211_local *local = sdata->local; 222 struct sk_buff *skb; 223 struct ieee80211_mgmt *mgmt; 224 bool amsdu = ieee80211_hw_check(&local->hw, SUPPORTS_AMSDU_IN_AMPDU); 225 u16 capab; 226 227 skb = dev_alloc_skb(sizeof(*mgmt) + 228 2 + sizeof(struct ieee80211_addba_ext_ie) + 229 local->hw.extra_tx_headroom); 230 if (!skb) 231 return; 232 233 skb_reserve(skb, local->hw.extra_tx_headroom); 234 mgmt = skb_put_zero(skb, 24); 235 memcpy(mgmt->da, da, ETH_ALEN); 236 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN); 237 if (sdata->vif.type == NL80211_IFTYPE_AP || 238 sdata->vif.type == NL80211_IFTYPE_AP_VLAN || 239 sdata->vif.type == NL80211_IFTYPE_MESH_POINT) 240 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN); 241 else if (sdata->vif.type == NL80211_IFTYPE_STATION) 242 memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN); 243 else if (sdata->vif.type == NL80211_IFTYPE_ADHOC) 244 memcpy(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN); 245 246 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 247 IEEE80211_STYPE_ACTION); 248 249 skb_put(skb, 1 + sizeof(mgmt->u.action.u.addba_resp)); 250 mgmt->u.action.category = WLAN_CATEGORY_BACK; 251 mgmt->u.action.u.addba_resp.action_code = WLAN_ACTION_ADDBA_RESP; 252 mgmt->u.action.u.addba_resp.dialog_token = dialog_token; 253 254 capab = u16_encode_bits(amsdu, IEEE80211_ADDBA_PARAM_AMSDU_MASK); 255 capab |= u16_encode_bits(policy, IEEE80211_ADDBA_PARAM_POLICY_MASK); 256 capab |= u16_encode_bits(tid, IEEE80211_ADDBA_PARAM_TID_MASK); 257 capab |= u16_encode_bits(buf_size, IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK); 258 259 mgmt->u.action.u.addba_resp.capab = cpu_to_le16(capab); 260 mgmt->u.action.u.addba_resp.timeout = cpu_to_le16(timeout); 261 mgmt->u.action.u.addba_resp.status = cpu_to_le16(status); 262 263 if (sta->sta.he_cap.has_he && addbaext) 264 ieee80211_add_addbaext(sdata, skb, addbaext); 265 266 ieee80211_tx_skb(sdata, skb); 267 } 268 269 void ___ieee80211_start_rx_ba_session(struct sta_info *sta, 270 u8 dialog_token, u16 timeout, 271 u16 start_seq_num, u16 ba_policy, u16 tid, 272 u16 buf_size, bool tx, bool auto_seq, 273 const struct ieee80211_addba_ext_ie *addbaext) 274 { 275 struct ieee80211_local *local = sta->sdata->local; 276 struct tid_ampdu_rx *tid_agg_rx; 277 struct ieee80211_ampdu_params params = { 278 .sta = &sta->sta, 279 .action = IEEE80211_AMPDU_RX_START, 280 .tid = tid, 281 .amsdu = false, 282 .timeout = timeout, 283 .ssn = start_seq_num, 284 }; 285 int i, ret = -EOPNOTSUPP; 286 u16 status = WLAN_STATUS_REQUEST_DECLINED; 287 u16 max_buf_size; 288 289 if (tid >= IEEE80211_FIRST_TSPEC_TSID) { 290 ht_dbg(sta->sdata, 291 "STA %pM requests BA session on unsupported tid %d\n", 292 sta->sta.addr, tid); 293 goto end; 294 } 295 296 if (!sta->sta.ht_cap.ht_supported && 297 sta->sdata->vif.bss_conf.chandef.chan->band != NL80211_BAND_6GHZ) { 298 ht_dbg(sta->sdata, 299 "STA %pM erroneously requests BA session on tid %d w/o QoS\n", 300 sta->sta.addr, tid); 301 /* send a response anyway, it's an error case if we get here */ 302 goto end; 303 } 304 305 if (test_sta_flag(sta, WLAN_STA_BLOCK_BA)) { 306 ht_dbg(sta->sdata, 307 "Suspend in progress - Denying ADDBA request (%pM tid %d)\n", 308 sta->sta.addr, tid); 309 goto end; 310 } 311 312 if (sta->sta.he_cap.has_he) 313 max_buf_size = IEEE80211_MAX_AMPDU_BUF; 314 else 315 max_buf_size = IEEE80211_MAX_AMPDU_BUF_HT; 316 317 /* sanity check for incoming parameters: 318 * check if configuration can support the BA policy 319 * and if buffer size does not exceeds max value */ 320 /* XXX: check own ht delayed BA capability?? */ 321 if (((ba_policy != 1) && 322 (!(sta->sta.ht_cap.cap & IEEE80211_HT_CAP_DELAY_BA))) || 323 (buf_size > max_buf_size)) { 324 status = WLAN_STATUS_INVALID_QOS_PARAM; 325 ht_dbg_ratelimited(sta->sdata, 326 "AddBA Req with bad params from %pM on tid %u. policy %d, buffer size %d\n", 327 sta->sta.addr, tid, ba_policy, buf_size); 328 goto end; 329 } 330 /* determine default buffer size */ 331 if (buf_size == 0) 332 buf_size = max_buf_size; 333 334 /* make sure the size doesn't exceed the maximum supported by the hw */ 335 if (buf_size > sta->sta.max_rx_aggregation_subframes) 336 buf_size = sta->sta.max_rx_aggregation_subframes; 337 params.buf_size = buf_size; 338 339 ht_dbg(sta->sdata, "AddBA Req buf_size=%d for %pM\n", 340 buf_size, sta->sta.addr); 341 342 /* examine state machine */ 343 lockdep_assert_held(&sta->ampdu_mlme.mtx); 344 345 if (test_bit(tid, sta->ampdu_mlme.agg_session_valid)) { 346 if (sta->ampdu_mlme.tid_rx_token[tid] == dialog_token) { 347 struct tid_ampdu_rx *tid_rx; 348 349 ht_dbg_ratelimited(sta->sdata, 350 "updated AddBA Req from %pM on tid %u\n", 351 sta->sta.addr, tid); 352 /* We have no API to update the timeout value in the 353 * driver so reject the timeout update if the timeout 354 * changed. If it did not change, i.e., no real update, 355 * just reply with success. 356 */ 357 rcu_read_lock(); 358 tid_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]); 359 if (tid_rx && tid_rx->timeout == timeout) 360 status = WLAN_STATUS_SUCCESS; 361 else 362 status = WLAN_STATUS_REQUEST_DECLINED; 363 rcu_read_unlock(); 364 goto end; 365 } 366 367 ht_dbg_ratelimited(sta->sdata, 368 "unexpected AddBA Req from %pM on tid %u\n", 369 sta->sta.addr, tid); 370 371 /* delete existing Rx BA session on the same tid */ 372 ___ieee80211_stop_rx_ba_session(sta, tid, WLAN_BACK_RECIPIENT, 373 WLAN_STATUS_UNSPECIFIED_QOS, 374 false); 375 } 376 377 if (ieee80211_hw_check(&local->hw, SUPPORTS_REORDERING_BUFFER)) { 378 ret = drv_ampdu_action(local, sta->sdata, ¶ms); 379 ht_dbg(sta->sdata, 380 "Rx A-MPDU request on %pM tid %d result %d\n", 381 sta->sta.addr, tid, ret); 382 if (!ret) 383 status = WLAN_STATUS_SUCCESS; 384 goto end; 385 } 386 387 /* prepare A-MPDU MLME for Rx aggregation */ 388 tid_agg_rx = kzalloc(sizeof(*tid_agg_rx), GFP_KERNEL); 389 if (!tid_agg_rx) 390 goto end; 391 392 spin_lock_init(&tid_agg_rx->reorder_lock); 393 394 /* rx timer */ 395 timer_setup(&tid_agg_rx->session_timer, 396 sta_rx_agg_session_timer_expired, TIMER_DEFERRABLE); 397 398 /* rx reorder timer */ 399 timer_setup(&tid_agg_rx->reorder_timer, 400 sta_rx_agg_reorder_timer_expired, 0); 401 402 /* prepare reordering buffer */ 403 tid_agg_rx->reorder_buf = 404 kcalloc(buf_size, sizeof(struct sk_buff_head), GFP_KERNEL); 405 tid_agg_rx->reorder_time = 406 kcalloc(buf_size, sizeof(unsigned long), GFP_KERNEL); 407 if (!tid_agg_rx->reorder_buf || !tid_agg_rx->reorder_time) { 408 kfree(tid_agg_rx->reorder_buf); 409 kfree(tid_agg_rx->reorder_time); 410 kfree(tid_agg_rx); 411 goto end; 412 } 413 414 for (i = 0; i < buf_size; i++) 415 __skb_queue_head_init(&tid_agg_rx->reorder_buf[i]); 416 417 ret = drv_ampdu_action(local, sta->sdata, ¶ms); 418 ht_dbg(sta->sdata, "Rx A-MPDU request on %pM tid %d result %d\n", 419 sta->sta.addr, tid, ret); 420 if (ret) { 421 kfree(tid_agg_rx->reorder_buf); 422 kfree(tid_agg_rx->reorder_time); 423 kfree(tid_agg_rx); 424 goto end; 425 } 426 427 /* update data */ 428 tid_agg_rx->ssn = start_seq_num; 429 tid_agg_rx->head_seq_num = start_seq_num; 430 tid_agg_rx->buf_size = buf_size; 431 tid_agg_rx->timeout = timeout; 432 tid_agg_rx->stored_mpdu_num = 0; 433 tid_agg_rx->auto_seq = auto_seq; 434 tid_agg_rx->started = false; 435 tid_agg_rx->reorder_buf_filtered = 0; 436 tid_agg_rx->tid = tid; 437 tid_agg_rx->sta = sta; 438 status = WLAN_STATUS_SUCCESS; 439 440 /* activate it for RX */ 441 rcu_assign_pointer(sta->ampdu_mlme.tid_rx[tid], tid_agg_rx); 442 443 if (timeout) { 444 mod_timer(&tid_agg_rx->session_timer, TU_TO_EXP_TIME(timeout)); 445 tid_agg_rx->last_rx = jiffies; 446 } 447 448 end: 449 if (status == WLAN_STATUS_SUCCESS) { 450 __set_bit(tid, sta->ampdu_mlme.agg_session_valid); 451 __clear_bit(tid, sta->ampdu_mlme.unexpected_agg); 452 sta->ampdu_mlme.tid_rx_token[tid] = dialog_token; 453 } 454 455 if (tx) 456 ieee80211_send_addba_resp(sta, sta->sta.addr, tid, 457 dialog_token, status, 1, buf_size, 458 timeout, addbaext); 459 } 460 461 static void __ieee80211_start_rx_ba_session(struct sta_info *sta, 462 u8 dialog_token, u16 timeout, 463 u16 start_seq_num, u16 ba_policy, 464 u16 tid, u16 buf_size, bool tx, 465 bool auto_seq, 466 const struct ieee80211_addba_ext_ie *addbaext) 467 { 468 mutex_lock(&sta->ampdu_mlme.mtx); 469 ___ieee80211_start_rx_ba_session(sta, dialog_token, timeout, 470 start_seq_num, ba_policy, tid, 471 buf_size, tx, auto_seq, addbaext); 472 mutex_unlock(&sta->ampdu_mlme.mtx); 473 } 474 475 void ieee80211_process_addba_request(struct ieee80211_local *local, 476 struct sta_info *sta, 477 struct ieee80211_mgmt *mgmt, 478 size_t len) 479 { 480 u16 capab, tid, timeout, ba_policy, buf_size, start_seq_num; 481 struct ieee802_11_elems *elems = NULL; 482 u8 dialog_token; 483 int ies_len; 484 485 /* extract session parameters from addba request frame */ 486 dialog_token = mgmt->u.action.u.addba_req.dialog_token; 487 timeout = le16_to_cpu(mgmt->u.action.u.addba_req.timeout); 488 start_seq_num = 489 le16_to_cpu(mgmt->u.action.u.addba_req.start_seq_num) >> 4; 490 491 capab = le16_to_cpu(mgmt->u.action.u.addba_req.capab); 492 ba_policy = (capab & IEEE80211_ADDBA_PARAM_POLICY_MASK) >> 1; 493 tid = (capab & IEEE80211_ADDBA_PARAM_TID_MASK) >> 2; 494 buf_size = (capab & IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK) >> 6; 495 496 ies_len = len - offsetof(struct ieee80211_mgmt, 497 u.action.u.addba_req.variable); 498 if (ies_len) { 499 elems = ieee802_11_parse_elems(mgmt->u.action.u.addba_req.variable, 500 ies_len, true, mgmt->bssid, NULL); 501 if (!elems || elems->parse_error) 502 goto free; 503 } 504 505 __ieee80211_start_rx_ba_session(sta, dialog_token, timeout, 506 start_seq_num, ba_policy, tid, 507 buf_size, true, false, 508 elems ? elems->addba_ext_ie : NULL); 509 free: 510 kfree(elems); 511 } 512 513 void ieee80211_manage_rx_ba_offl(struct ieee80211_vif *vif, 514 const u8 *addr, unsigned int tid) 515 { 516 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif); 517 struct ieee80211_local *local = sdata->local; 518 struct sta_info *sta; 519 520 rcu_read_lock(); 521 sta = sta_info_get_bss(sdata, addr); 522 if (!sta) 523 goto unlock; 524 525 set_bit(tid, sta->ampdu_mlme.tid_rx_manage_offl); 526 ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work); 527 unlock: 528 rcu_read_unlock(); 529 } 530 EXPORT_SYMBOL(ieee80211_manage_rx_ba_offl); 531 532 void ieee80211_rx_ba_timer_expired(struct ieee80211_vif *vif, 533 const u8 *addr, unsigned int tid) 534 { 535 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif); 536 struct ieee80211_local *local = sdata->local; 537 struct sta_info *sta; 538 539 rcu_read_lock(); 540 sta = sta_info_get_bss(sdata, addr); 541 if (!sta) 542 goto unlock; 543 544 set_bit(tid, sta->ampdu_mlme.tid_rx_timer_expired); 545 ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work); 546 547 unlock: 548 rcu_read_unlock(); 549 } 550 EXPORT_SYMBOL(ieee80211_rx_ba_timer_expired); 551