1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (c) 2008, 2009 open80211s Ltd. 4 * Copyright (C) 2019, 2021-2023 Intel Corporation 5 * Author: Luis Carlos Cobo <luisca@cozybit.com> 6 */ 7 #include <linux/gfp.h> 8 #include <linux/kernel.h> 9 #include <linux/random.h> 10 #include <linux/rculist.h> 11 12 #include "ieee80211_i.h" 13 #include "rate.h" 14 #include "mesh.h" 15 16 #define PLINK_CNF_AID(mgmt) ((mgmt)->u.action.u.self_prot.variable + 2) 17 #define PLINK_GET_LLID(p) (p + 2) 18 #define PLINK_GET_PLID(p) (p + 4) 19 20 #define mod_plink_timer(s, t) (mod_timer(&s->mesh->plink_timer, \ 21 jiffies + msecs_to_jiffies(t))) 22 23 enum plink_event { 24 PLINK_UNDEFINED, 25 OPN_ACPT, 26 OPN_RJCT, 27 OPN_IGNR, 28 CNF_ACPT, 29 CNF_RJCT, 30 CNF_IGNR, 31 CLS_ACPT, 32 CLS_IGNR 33 }; 34 35 static const char * const mplstates[] = { 36 [NL80211_PLINK_LISTEN] = "LISTEN", 37 [NL80211_PLINK_OPN_SNT] = "OPN-SNT", 38 [NL80211_PLINK_OPN_RCVD] = "OPN-RCVD", 39 [NL80211_PLINK_CNF_RCVD] = "CNF_RCVD", 40 [NL80211_PLINK_ESTAB] = "ESTAB", 41 [NL80211_PLINK_HOLDING] = "HOLDING", 42 [NL80211_PLINK_BLOCKED] = "BLOCKED" 43 }; 44 45 static const char * const mplevents[] = { 46 [PLINK_UNDEFINED] = "NONE", 47 [OPN_ACPT] = "OPN_ACPT", 48 [OPN_RJCT] = "OPN_RJCT", 49 [OPN_IGNR] = "OPN_IGNR", 50 [CNF_ACPT] = "CNF_ACPT", 51 [CNF_RJCT] = "CNF_RJCT", 52 [CNF_IGNR] = "CNF_IGNR", 53 [CLS_ACPT] = "CLS_ACPT", 54 [CLS_IGNR] = "CLS_IGNR" 55 }; 56 57 /* We only need a valid sta if user configured a minimum rssi_threshold. */ 58 static bool rssi_threshold_check(struct ieee80211_sub_if_data *sdata, 59 struct sta_info *sta) 60 { 61 s32 rssi_threshold = sdata->u.mesh.mshcfg.rssi_threshold; 62 return rssi_threshold == 0 || 63 (sta && 64 (s8)-ewma_signal_read(&sta->deflink.rx_stats_avg.signal) > 65 rssi_threshold); 66 } 67 68 /** 69 * mesh_plink_fsm_restart - restart a mesh peer link finite state machine 70 * 71 * @sta: mesh peer link to restart 72 * 73 * Locking: this function must be called holding sta->mesh->plink_lock 74 */ 75 static inline void mesh_plink_fsm_restart(struct sta_info *sta) 76 { 77 lockdep_assert_held(&sta->mesh->plink_lock); 78 sta->mesh->plink_state = NL80211_PLINK_LISTEN; 79 sta->mesh->llid = sta->mesh->plid = sta->mesh->reason = 0; 80 sta->mesh->plink_retries = 0; 81 } 82 83 /* 84 * mesh_set_short_slot_time - enable / disable ERP short slot time. 85 * 86 * The standard indirectly mandates mesh STAs to turn off short slot time by 87 * disallowing advertising this (802.11-2012 8.4.1.4), but that doesn't mean we 88 * can't be sneaky about it. Enable short slot time if all mesh STAs in the 89 * MBSS support ERP rates. 90 * 91 * Returns BSS_CHANGED_ERP_SLOT or 0 for no change. 92 */ 93 static u64 mesh_set_short_slot_time(struct ieee80211_sub_if_data *sdata) 94 { 95 struct ieee80211_local *local = sdata->local; 96 struct ieee80211_supported_band *sband; 97 struct sta_info *sta; 98 u32 erp_rates = 0; 99 u64 changed = 0; 100 int i; 101 bool short_slot = false; 102 103 sband = ieee80211_get_sband(sdata); 104 if (!sband) 105 return changed; 106 107 if (sband->band == NL80211_BAND_5GHZ) { 108 /* (IEEE 802.11-2012 19.4.5) */ 109 short_slot = true; 110 goto out; 111 } else if (sband->band != NL80211_BAND_2GHZ) { 112 goto out; 113 } 114 115 for (i = 0; i < sband->n_bitrates; i++) 116 if (sband->bitrates[i].flags & IEEE80211_RATE_ERP_G) 117 erp_rates |= BIT(i); 118 119 if (!erp_rates) 120 goto out; 121 122 rcu_read_lock(); 123 list_for_each_entry_rcu(sta, &local->sta_list, list) { 124 if (sdata != sta->sdata || 125 sta->mesh->plink_state != NL80211_PLINK_ESTAB) 126 continue; 127 128 short_slot = false; 129 if (erp_rates & sta->sta.deflink.supp_rates[sband->band]) 130 short_slot = true; 131 else 132 break; 133 } 134 rcu_read_unlock(); 135 136 out: 137 if (sdata->vif.bss_conf.use_short_slot != short_slot) { 138 sdata->vif.bss_conf.use_short_slot = short_slot; 139 changed = BSS_CHANGED_ERP_SLOT; 140 mpl_dbg(sdata, "mesh_plink %pM: ERP short slot time %d\n", 141 sdata->vif.addr, short_slot); 142 } 143 return changed; 144 } 145 146 /** 147 * mesh_set_ht_prot_mode - set correct HT protection mode 148 * @sdata: the (mesh) interface to handle 149 * 150 * Section 9.23.3.5 of IEEE 80211-2012 describes the protection rules for HT 151 * mesh STA in a MBSS. Three HT protection modes are supported for now, non-HT 152 * mixed mode, 20MHz-protection and no-protection mode. non-HT mixed mode is 153 * selected if any non-HT peers are present in our MBSS. 20MHz-protection mode 154 * is selected if all peers in our 20/40MHz MBSS support HT and at least one 155 * HT20 peer is present. Otherwise no-protection mode is selected. 156 * 157 * Returns: BSS_CHANGED_HT or 0 for no change 158 */ 159 static u64 mesh_set_ht_prot_mode(struct ieee80211_sub_if_data *sdata) 160 { 161 struct ieee80211_local *local = sdata->local; 162 struct sta_info *sta; 163 u16 ht_opmode; 164 bool non_ht_sta = false, ht20_sta = false; 165 166 switch (sdata->vif.bss_conf.chandef.width) { 167 case NL80211_CHAN_WIDTH_20_NOHT: 168 case NL80211_CHAN_WIDTH_5: 169 case NL80211_CHAN_WIDTH_10: 170 return 0; 171 default: 172 break; 173 } 174 175 rcu_read_lock(); 176 list_for_each_entry_rcu(sta, &local->sta_list, list) { 177 if (sdata != sta->sdata || 178 sta->mesh->plink_state != NL80211_PLINK_ESTAB) 179 continue; 180 181 if (sta->sta.deflink.bandwidth > IEEE80211_STA_RX_BW_20) 182 continue; 183 184 if (!sta->sta.deflink.ht_cap.ht_supported) { 185 mpl_dbg(sdata, "nonHT sta (%pM) is present\n", 186 sta->sta.addr); 187 non_ht_sta = true; 188 break; 189 } 190 191 mpl_dbg(sdata, "HT20 sta (%pM) is present\n", sta->sta.addr); 192 ht20_sta = true; 193 } 194 rcu_read_unlock(); 195 196 if (non_ht_sta) 197 ht_opmode = IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED; 198 else if (ht20_sta && 199 sdata->vif.bss_conf.chandef.width > NL80211_CHAN_WIDTH_20) 200 ht_opmode = IEEE80211_HT_OP_MODE_PROTECTION_20MHZ; 201 else 202 ht_opmode = IEEE80211_HT_OP_MODE_PROTECTION_NONE; 203 204 if (sdata->vif.bss_conf.ht_operation_mode == ht_opmode) 205 return 0; 206 207 sdata->vif.bss_conf.ht_operation_mode = ht_opmode; 208 sdata->u.mesh.mshcfg.ht_opmode = ht_opmode; 209 mpl_dbg(sdata, "selected new HT protection mode %d\n", ht_opmode); 210 return BSS_CHANGED_HT; 211 } 212 213 static int mesh_plink_frame_tx(struct ieee80211_sub_if_data *sdata, 214 struct sta_info *sta, 215 enum ieee80211_self_protected_actioncode action, 216 u8 *da, u16 llid, u16 plid, u16 reason) 217 { 218 struct ieee80211_local *local = sdata->local; 219 struct sk_buff *skb; 220 struct ieee80211_tx_info *info; 221 struct ieee80211_mgmt *mgmt; 222 bool include_plid = false; 223 u16 peering_proto = 0; 224 u8 *pos, ie_len = 4; 225 u8 ie_len_he_cap, ie_len_eht_cap; 226 int hdr_len = offsetofend(struct ieee80211_mgmt, u.action.u.self_prot); 227 int err = -ENOMEM; 228 229 ie_len_he_cap = ieee80211_ie_len_he_cap(sdata, 230 NL80211_IFTYPE_MESH_POINT); 231 ie_len_eht_cap = ieee80211_ie_len_eht_cap(sdata, 232 NL80211_IFTYPE_MESH_POINT); 233 skb = dev_alloc_skb(local->tx_headroom + 234 hdr_len + 235 2 + /* capability info */ 236 2 + /* AID */ 237 2 + 8 + /* supported rates */ 238 2 + (IEEE80211_MAX_SUPP_RATES - 8) + 239 2 + sdata->u.mesh.mesh_id_len + 240 2 + sizeof(struct ieee80211_meshconf_ie) + 241 2 + sizeof(struct ieee80211_ht_cap) + 242 2 + sizeof(struct ieee80211_ht_operation) + 243 2 + sizeof(struct ieee80211_vht_cap) + 244 2 + sizeof(struct ieee80211_vht_operation) + 245 ie_len_he_cap + 246 2 + 1 + sizeof(struct ieee80211_he_operation) + 247 sizeof(struct ieee80211_he_6ghz_oper) + 248 2 + 1 + sizeof(struct ieee80211_he_6ghz_capa) + 249 ie_len_eht_cap + 250 2 + 1 + offsetof(struct ieee80211_eht_operation, optional) + 251 offsetof(struct ieee80211_eht_operation_info, optional) + 252 2 + 8 + /* peering IE */ 253 sdata->u.mesh.ie_len); 254 if (!skb) 255 return err; 256 info = IEEE80211_SKB_CB(skb); 257 skb_reserve(skb, local->tx_headroom); 258 mgmt = skb_put_zero(skb, hdr_len); 259 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 260 IEEE80211_STYPE_ACTION); 261 memcpy(mgmt->da, da, ETH_ALEN); 262 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN); 263 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN); 264 mgmt->u.action.category = WLAN_CATEGORY_SELF_PROTECTED; 265 mgmt->u.action.u.self_prot.action_code = action; 266 267 if (action != WLAN_SP_MESH_PEERING_CLOSE) { 268 struct ieee80211_supported_band *sband; 269 enum nl80211_band band; 270 271 sband = ieee80211_get_sband(sdata); 272 if (!sband) { 273 err = -EINVAL; 274 goto free; 275 } 276 band = sband->band; 277 278 /* capability info */ 279 pos = skb_put_zero(skb, 2); 280 if (action == WLAN_SP_MESH_PEERING_CONFIRM) { 281 /* AID */ 282 pos = skb_put(skb, 2); 283 put_unaligned_le16(sta->sta.aid, pos); 284 } 285 if (ieee80211_add_srates_ie(sdata, skb, true, band) || 286 ieee80211_add_ext_srates_ie(sdata, skb, true, band) || 287 mesh_add_rsn_ie(sdata, skb) || 288 mesh_add_meshid_ie(sdata, skb) || 289 mesh_add_meshconf_ie(sdata, skb)) 290 goto free; 291 } else { /* WLAN_SP_MESH_PEERING_CLOSE */ 292 info->flags |= IEEE80211_TX_CTL_NO_ACK; 293 if (mesh_add_meshid_ie(sdata, skb)) 294 goto free; 295 } 296 297 /* Add Mesh Peering Management element */ 298 switch (action) { 299 case WLAN_SP_MESH_PEERING_OPEN: 300 break; 301 case WLAN_SP_MESH_PEERING_CONFIRM: 302 ie_len += 2; 303 include_plid = true; 304 break; 305 case WLAN_SP_MESH_PEERING_CLOSE: 306 if (plid) { 307 ie_len += 2; 308 include_plid = true; 309 } 310 ie_len += 2; /* reason code */ 311 break; 312 default: 313 err = -EINVAL; 314 goto free; 315 } 316 317 if (WARN_ON(skb_tailroom(skb) < 2 + ie_len)) 318 goto free; 319 320 pos = skb_put(skb, 2 + ie_len); 321 *pos++ = WLAN_EID_PEER_MGMT; 322 *pos++ = ie_len; 323 memcpy(pos, &peering_proto, 2); 324 pos += 2; 325 put_unaligned_le16(llid, pos); 326 pos += 2; 327 if (include_plid) { 328 put_unaligned_le16(plid, pos); 329 pos += 2; 330 } 331 if (action == WLAN_SP_MESH_PEERING_CLOSE) { 332 put_unaligned_le16(reason, pos); 333 pos += 2; 334 } 335 336 if (action != WLAN_SP_MESH_PEERING_CLOSE) { 337 if (mesh_add_ht_cap_ie(sdata, skb) || 338 mesh_add_ht_oper_ie(sdata, skb) || 339 mesh_add_vht_cap_ie(sdata, skb) || 340 mesh_add_vht_oper_ie(sdata, skb) || 341 mesh_add_he_cap_ie(sdata, skb, ie_len_he_cap) || 342 mesh_add_he_oper_ie(sdata, skb) || 343 mesh_add_he_6ghz_cap_ie(sdata, skb) || 344 mesh_add_eht_cap_ie(sdata, skb, ie_len_eht_cap) || 345 mesh_add_eht_oper_ie(sdata, skb)) 346 goto free; 347 } 348 349 if (mesh_add_vendor_ies(sdata, skb)) 350 goto free; 351 352 ieee80211_tx_skb(sdata, skb); 353 return 0; 354 free: 355 kfree_skb(skb); 356 return err; 357 } 358 359 /** 360 * __mesh_plink_deactivate - deactivate mesh peer link 361 * 362 * @sta: mesh peer link to deactivate 363 * 364 * Mesh paths with this peer as next hop should be flushed 365 * by the caller outside of plink_lock. 366 * 367 * Returns: beacon changed flag if the beacon content changed. 368 * 369 * Locking: the caller must hold sta->mesh->plink_lock 370 */ 371 static u64 __mesh_plink_deactivate(struct sta_info *sta) 372 { 373 struct ieee80211_sub_if_data *sdata = sta->sdata; 374 u64 changed = 0; 375 376 lockdep_assert_held(&sta->mesh->plink_lock); 377 378 if (sta->mesh->plink_state == NL80211_PLINK_ESTAB) 379 changed = mesh_plink_dec_estab_count(sdata); 380 sta->mesh->plink_state = NL80211_PLINK_BLOCKED; 381 382 ieee80211_mps_sta_status_update(sta); 383 changed |= ieee80211_mps_set_sta_local_pm(sta, 384 NL80211_MESH_POWER_UNKNOWN); 385 386 return changed; 387 } 388 389 /** 390 * mesh_plink_deactivate - deactivate mesh peer link 391 * 392 * @sta: mesh peer link to deactivate 393 * 394 * All mesh paths with this peer as next hop will be flushed 395 * 396 * Returns: beacon changed flag if the beacon content changed. 397 */ 398 u64 mesh_plink_deactivate(struct sta_info *sta) 399 { 400 struct ieee80211_sub_if_data *sdata = sta->sdata; 401 u64 changed; 402 403 spin_lock_bh(&sta->mesh->plink_lock); 404 changed = __mesh_plink_deactivate(sta); 405 406 if (!sdata->u.mesh.user_mpm) { 407 sta->mesh->reason = WLAN_REASON_MESH_PEER_CANCELED; 408 mesh_plink_frame_tx(sdata, sta, WLAN_SP_MESH_PEERING_CLOSE, 409 sta->sta.addr, sta->mesh->llid, 410 sta->mesh->plid, sta->mesh->reason); 411 } 412 spin_unlock_bh(&sta->mesh->plink_lock); 413 if (!sdata->u.mesh.user_mpm) 414 del_timer_sync(&sta->mesh->plink_timer); 415 mesh_path_flush_by_nexthop(sta); 416 417 /* make sure no readers can access nexthop sta from here on */ 418 synchronize_net(); 419 420 return changed; 421 } 422 423 static void mesh_sta_info_init(struct ieee80211_sub_if_data *sdata, 424 struct sta_info *sta, 425 struct ieee802_11_elems *elems) 426 { 427 struct ieee80211_local *local = sdata->local; 428 struct ieee80211_supported_band *sband; 429 u32 rates, basic_rates = 0, changed = 0; 430 enum ieee80211_sta_rx_bandwidth bw = sta->sta.deflink.bandwidth; 431 432 sband = ieee80211_get_sband(sdata); 433 if (!sband) 434 return; 435 436 rates = ieee80211_sta_get_rates(sdata, elems, sband->band, 437 &basic_rates); 438 439 spin_lock_bh(&sta->mesh->plink_lock); 440 sta->deflink.rx_stats.last_rx = jiffies; 441 442 /* rates and capabilities don't change during peering */ 443 if (sta->mesh->plink_state == NL80211_PLINK_ESTAB && 444 sta->mesh->processed_beacon) 445 goto out; 446 sta->mesh->processed_beacon = true; 447 448 if (sta->sta.deflink.supp_rates[sband->band] != rates) 449 changed |= IEEE80211_RC_SUPP_RATES_CHANGED; 450 sta->sta.deflink.supp_rates[sband->band] = rates; 451 452 if (ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband, 453 elems->ht_cap_elem, 454 &sta->deflink)) 455 changed |= IEEE80211_RC_BW_CHANGED; 456 457 ieee80211_vht_cap_ie_to_sta_vht_cap(sdata, sband, 458 elems->vht_cap_elem, NULL, 459 &sta->deflink); 460 461 ieee80211_he_cap_ie_to_sta_he_cap(sdata, sband, elems->he_cap, 462 elems->he_cap_len, 463 elems->he_6ghz_capa, 464 &sta->deflink); 465 466 ieee80211_eht_cap_ie_to_sta_eht_cap(sdata, sband, elems->he_cap, 467 elems->he_cap_len, 468 elems->eht_cap, elems->eht_cap_len, 469 &sta->deflink); 470 471 if (bw != sta->sta.deflink.bandwidth) 472 changed |= IEEE80211_RC_BW_CHANGED; 473 474 /* HT peer is operating 20MHz-only */ 475 if (elems->ht_operation && 476 !(elems->ht_operation->ht_param & 477 IEEE80211_HT_PARAM_CHAN_WIDTH_ANY)) { 478 if (sta->sta.deflink.bandwidth != IEEE80211_STA_RX_BW_20) 479 changed |= IEEE80211_RC_BW_CHANGED; 480 sta->sta.deflink.bandwidth = IEEE80211_STA_RX_BW_20; 481 } 482 483 if (!test_sta_flag(sta, WLAN_STA_RATE_CONTROL)) 484 rate_control_rate_init(sta); 485 else 486 rate_control_rate_update(local, sband, sta, 0, changed); 487 out: 488 spin_unlock_bh(&sta->mesh->plink_lock); 489 } 490 491 static int mesh_allocate_aid(struct ieee80211_sub_if_data *sdata) 492 { 493 struct sta_info *sta; 494 unsigned long *aid_map; 495 int aid; 496 497 aid_map = bitmap_zalloc(IEEE80211_MAX_AID + 1, GFP_KERNEL); 498 if (!aid_map) 499 return -ENOMEM; 500 501 /* reserve aid 0 for mcast indication */ 502 __set_bit(0, aid_map); 503 504 rcu_read_lock(); 505 list_for_each_entry_rcu(sta, &sdata->local->sta_list, list) 506 __set_bit(sta->sta.aid, aid_map); 507 rcu_read_unlock(); 508 509 aid = find_first_zero_bit(aid_map, IEEE80211_MAX_AID + 1); 510 bitmap_free(aid_map); 511 512 if (aid > IEEE80211_MAX_AID) 513 return -ENOBUFS; 514 515 return aid; 516 } 517 518 static struct sta_info * 519 __mesh_sta_info_alloc(struct ieee80211_sub_if_data *sdata, u8 *hw_addr) 520 { 521 struct sta_info *sta; 522 int aid; 523 524 if (sdata->local->num_sta >= MESH_MAX_PLINKS) 525 return NULL; 526 527 aid = mesh_allocate_aid(sdata); 528 if (aid < 0) 529 return NULL; 530 531 sta = sta_info_alloc(sdata, hw_addr, GFP_KERNEL); 532 if (!sta) 533 return NULL; 534 535 sta->mesh->plink_state = NL80211_PLINK_LISTEN; 536 sta->sta.wme = true; 537 sta->sta.aid = aid; 538 539 sta_info_pre_move_state(sta, IEEE80211_STA_AUTH); 540 sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC); 541 sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED); 542 543 return sta; 544 } 545 546 static struct sta_info * 547 mesh_sta_info_alloc(struct ieee80211_sub_if_data *sdata, u8 *addr, 548 struct ieee802_11_elems *elems, 549 struct ieee80211_rx_status *rx_status) 550 { 551 struct sta_info *sta = NULL; 552 553 /* Userspace handles station allocation */ 554 if (sdata->u.mesh.user_mpm || 555 sdata->u.mesh.security & IEEE80211_MESH_SEC_AUTHED) { 556 if (mesh_peer_accepts_plinks(elems) && 557 mesh_plink_availables(sdata)) { 558 int sig = 0; 559 560 if (ieee80211_hw_check(&sdata->local->hw, SIGNAL_DBM)) 561 sig = rx_status->signal; 562 563 cfg80211_notify_new_peer_candidate(sdata->dev, addr, 564 elems->ie_start, 565 elems->total_len, 566 sig, GFP_KERNEL); 567 } 568 } else 569 sta = __mesh_sta_info_alloc(sdata, addr); 570 571 return sta; 572 } 573 574 /* 575 * mesh_sta_info_get - return mesh sta info entry for @addr. 576 * 577 * @sdata: local meshif 578 * @addr: peer's address 579 * @elems: IEs from beacon or mesh peering frame. 580 * @rx_status: rx status for the frame for signal reporting 581 * 582 * Return existing or newly allocated sta_info under RCU read lock. 583 * (re)initialize with given IEs. 584 */ 585 static struct sta_info * 586 mesh_sta_info_get(struct ieee80211_sub_if_data *sdata, 587 u8 *addr, struct ieee802_11_elems *elems, 588 struct ieee80211_rx_status *rx_status) __acquires(RCU) 589 { 590 struct sta_info *sta = NULL; 591 592 rcu_read_lock(); 593 sta = sta_info_get(sdata, addr); 594 if (sta) { 595 mesh_sta_info_init(sdata, sta, elems); 596 } else { 597 rcu_read_unlock(); 598 /* can't run atomic */ 599 sta = mesh_sta_info_alloc(sdata, addr, elems, rx_status); 600 if (!sta) { 601 rcu_read_lock(); 602 return NULL; 603 } 604 605 mesh_sta_info_init(sdata, sta, elems); 606 607 if (sta_info_insert_rcu(sta)) 608 return NULL; 609 } 610 611 return sta; 612 } 613 614 /* 615 * mesh_neighbour_update - update or initialize new mesh neighbor. 616 * 617 * @sdata: local meshif 618 * @addr: peer's address 619 * @elems: IEs from beacon or mesh peering frame 620 * @rx_status: rx status for the frame for signal reporting 621 * 622 * Initiates peering if appropriate. 623 */ 624 void mesh_neighbour_update(struct ieee80211_sub_if_data *sdata, 625 u8 *hw_addr, 626 struct ieee802_11_elems *elems, 627 struct ieee80211_rx_status *rx_status) 628 { 629 struct sta_info *sta; 630 u64 changed = 0; 631 632 sta = mesh_sta_info_get(sdata, hw_addr, elems, rx_status); 633 if (!sta) 634 goto out; 635 636 sta->mesh->connected_to_gate = elems->mesh_config->meshconf_form & 637 IEEE80211_MESHCONF_FORM_CONNECTED_TO_GATE; 638 639 if (mesh_peer_accepts_plinks(elems) && 640 sta->mesh->plink_state == NL80211_PLINK_LISTEN && 641 sdata->u.mesh.accepting_plinks && 642 sdata->u.mesh.mshcfg.auto_open_plinks && 643 rssi_threshold_check(sdata, sta)) 644 changed = mesh_plink_open(sta); 645 646 ieee80211_mps_frame_release(sta, elems); 647 out: 648 rcu_read_unlock(); 649 ieee80211_mbss_info_change_notify(sdata, changed); 650 } 651 652 void mesh_plink_timer(struct timer_list *t) 653 { 654 struct mesh_sta *mesh = from_timer(mesh, t, plink_timer); 655 struct sta_info *sta; 656 u16 reason = 0; 657 struct ieee80211_sub_if_data *sdata; 658 struct mesh_config *mshcfg; 659 enum ieee80211_self_protected_actioncode action = 0; 660 661 /* 662 * This STA is valid because sta_info_destroy() will 663 * del_timer_sync() this timer after having made sure 664 * it cannot be readded (by deleting the plink.) 665 */ 666 sta = mesh->plink_sta; 667 668 if (sta->sdata->local->quiescing) 669 return; 670 671 spin_lock_bh(&sta->mesh->plink_lock); 672 673 /* If a timer fires just before a state transition on another CPU, 674 * we may have already extended the timeout and changed state by the 675 * time we've acquired the lock and arrived here. In that case, 676 * skip this timer and wait for the new one. 677 */ 678 if (time_before(jiffies, sta->mesh->plink_timer.expires)) { 679 mpl_dbg(sta->sdata, 680 "Ignoring timer for %pM in state %s (timer adjusted)", 681 sta->sta.addr, mplstates[sta->mesh->plink_state]); 682 spin_unlock_bh(&sta->mesh->plink_lock); 683 return; 684 } 685 686 /* del_timer() and handler may race when entering these states */ 687 if (sta->mesh->plink_state == NL80211_PLINK_LISTEN || 688 sta->mesh->plink_state == NL80211_PLINK_ESTAB) { 689 mpl_dbg(sta->sdata, 690 "Ignoring timer for %pM in state %s (timer deleted)", 691 sta->sta.addr, mplstates[sta->mesh->plink_state]); 692 spin_unlock_bh(&sta->mesh->plink_lock); 693 return; 694 } 695 696 mpl_dbg(sta->sdata, 697 "Mesh plink timer for %pM fired on state %s\n", 698 sta->sta.addr, mplstates[sta->mesh->plink_state]); 699 sdata = sta->sdata; 700 mshcfg = &sdata->u.mesh.mshcfg; 701 702 switch (sta->mesh->plink_state) { 703 case NL80211_PLINK_OPN_RCVD: 704 case NL80211_PLINK_OPN_SNT: 705 /* retry timer */ 706 if (sta->mesh->plink_retries < mshcfg->dot11MeshMaxRetries) { 707 u32 rand; 708 mpl_dbg(sta->sdata, 709 "Mesh plink for %pM (retry, timeout): %d %d\n", 710 sta->sta.addr, sta->mesh->plink_retries, 711 sta->mesh->plink_timeout); 712 get_random_bytes(&rand, sizeof(u32)); 713 sta->mesh->plink_timeout = sta->mesh->plink_timeout + 714 rand % sta->mesh->plink_timeout; 715 ++sta->mesh->plink_retries; 716 mod_plink_timer(sta, sta->mesh->plink_timeout); 717 action = WLAN_SP_MESH_PEERING_OPEN; 718 break; 719 } 720 reason = WLAN_REASON_MESH_MAX_RETRIES; 721 fallthrough; 722 case NL80211_PLINK_CNF_RCVD: 723 /* confirm timer */ 724 if (!reason) 725 reason = WLAN_REASON_MESH_CONFIRM_TIMEOUT; 726 sta->mesh->plink_state = NL80211_PLINK_HOLDING; 727 mod_plink_timer(sta, mshcfg->dot11MeshHoldingTimeout); 728 action = WLAN_SP_MESH_PEERING_CLOSE; 729 break; 730 case NL80211_PLINK_HOLDING: 731 /* holding timer */ 732 del_timer(&sta->mesh->plink_timer); 733 mesh_plink_fsm_restart(sta); 734 break; 735 default: 736 break; 737 } 738 spin_unlock_bh(&sta->mesh->plink_lock); 739 if (action) 740 mesh_plink_frame_tx(sdata, sta, action, sta->sta.addr, 741 sta->mesh->llid, sta->mesh->plid, reason); 742 } 743 744 static inline void mesh_plink_timer_set(struct sta_info *sta, u32 timeout) 745 { 746 sta->mesh->plink_timeout = timeout; 747 mod_timer(&sta->mesh->plink_timer, jiffies + msecs_to_jiffies(timeout)); 748 } 749 750 static bool llid_in_use(struct ieee80211_sub_if_data *sdata, 751 u16 llid) 752 { 753 struct ieee80211_local *local = sdata->local; 754 bool in_use = false; 755 struct sta_info *sta; 756 757 rcu_read_lock(); 758 list_for_each_entry_rcu(sta, &local->sta_list, list) { 759 if (sdata != sta->sdata) 760 continue; 761 762 if (!memcmp(&sta->mesh->llid, &llid, sizeof(llid))) { 763 in_use = true; 764 break; 765 } 766 } 767 rcu_read_unlock(); 768 769 return in_use; 770 } 771 772 static u16 mesh_get_new_llid(struct ieee80211_sub_if_data *sdata) 773 { 774 u16 llid; 775 776 do { 777 get_random_bytes(&llid, sizeof(llid)); 778 } while (llid_in_use(sdata, llid)); 779 780 return llid; 781 } 782 783 u64 mesh_plink_open(struct sta_info *sta) 784 { 785 struct ieee80211_sub_if_data *sdata = sta->sdata; 786 u64 changed; 787 788 if (!test_sta_flag(sta, WLAN_STA_AUTH)) 789 return 0; 790 791 spin_lock_bh(&sta->mesh->plink_lock); 792 sta->mesh->llid = mesh_get_new_llid(sdata); 793 if (sta->mesh->plink_state != NL80211_PLINK_LISTEN && 794 sta->mesh->plink_state != NL80211_PLINK_BLOCKED) { 795 spin_unlock_bh(&sta->mesh->plink_lock); 796 return 0; 797 } 798 sta->mesh->plink_state = NL80211_PLINK_OPN_SNT; 799 mesh_plink_timer_set(sta, sdata->u.mesh.mshcfg.dot11MeshRetryTimeout); 800 spin_unlock_bh(&sta->mesh->plink_lock); 801 mpl_dbg(sdata, 802 "Mesh plink: starting establishment with %pM\n", 803 sta->sta.addr); 804 805 /* set the non-peer mode to active during peering */ 806 changed = ieee80211_mps_local_status_update(sdata); 807 808 mesh_plink_frame_tx(sdata, sta, WLAN_SP_MESH_PEERING_OPEN, 809 sta->sta.addr, sta->mesh->llid, 0, 0); 810 return changed; 811 } 812 813 u64 mesh_plink_block(struct sta_info *sta) 814 { 815 u64 changed; 816 817 spin_lock_bh(&sta->mesh->plink_lock); 818 changed = __mesh_plink_deactivate(sta); 819 sta->mesh->plink_state = NL80211_PLINK_BLOCKED; 820 spin_unlock_bh(&sta->mesh->plink_lock); 821 mesh_path_flush_by_nexthop(sta); 822 823 return changed; 824 } 825 826 static void mesh_plink_close(struct ieee80211_sub_if_data *sdata, 827 struct sta_info *sta, 828 enum plink_event event) 829 { 830 struct mesh_config *mshcfg = &sdata->u.mesh.mshcfg; 831 u16 reason = (event == CLS_ACPT) ? 832 WLAN_REASON_MESH_CLOSE : WLAN_REASON_MESH_CONFIG; 833 834 sta->mesh->reason = reason; 835 sta->mesh->plink_state = NL80211_PLINK_HOLDING; 836 mod_plink_timer(sta, mshcfg->dot11MeshHoldingTimeout); 837 } 838 839 static u64 mesh_plink_establish(struct ieee80211_sub_if_data *sdata, 840 struct sta_info *sta) 841 { 842 struct mesh_config *mshcfg = &sdata->u.mesh.mshcfg; 843 u64 changed = 0; 844 845 del_timer(&sta->mesh->plink_timer); 846 sta->mesh->plink_state = NL80211_PLINK_ESTAB; 847 changed |= mesh_plink_inc_estab_count(sdata); 848 changed |= mesh_set_ht_prot_mode(sdata); 849 changed |= mesh_set_short_slot_time(sdata); 850 mpl_dbg(sdata, "Mesh plink with %pM ESTABLISHED\n", sta->sta.addr); 851 ieee80211_mps_sta_status_update(sta); 852 changed |= ieee80211_mps_set_sta_local_pm(sta, mshcfg->power_mode); 853 return changed; 854 } 855 856 /** 857 * mesh_plink_fsm - step @sta MPM based on @event 858 * 859 * @sdata: interface 860 * @sta: mesh neighbor 861 * @event: peering event 862 * 863 * Return: changed MBSS flags 864 */ 865 static u64 mesh_plink_fsm(struct ieee80211_sub_if_data *sdata, 866 struct sta_info *sta, enum plink_event event) 867 { 868 struct mesh_config *mshcfg = &sdata->u.mesh.mshcfg; 869 enum ieee80211_self_protected_actioncode action = 0; 870 u64 changed = 0; 871 bool flush = false; 872 873 mpl_dbg(sdata, "peer %pM in state %s got event %s\n", sta->sta.addr, 874 mplstates[sta->mesh->plink_state], mplevents[event]); 875 876 spin_lock_bh(&sta->mesh->plink_lock); 877 switch (sta->mesh->plink_state) { 878 case NL80211_PLINK_LISTEN: 879 switch (event) { 880 case CLS_ACPT: 881 mesh_plink_fsm_restart(sta); 882 break; 883 case OPN_ACPT: 884 sta->mesh->plink_state = NL80211_PLINK_OPN_RCVD; 885 sta->mesh->llid = mesh_get_new_llid(sdata); 886 mesh_plink_timer_set(sta, 887 mshcfg->dot11MeshRetryTimeout); 888 889 /* set the non-peer mode to active during peering */ 890 changed |= ieee80211_mps_local_status_update(sdata); 891 action = WLAN_SP_MESH_PEERING_OPEN; 892 break; 893 default: 894 break; 895 } 896 break; 897 case NL80211_PLINK_OPN_SNT: 898 switch (event) { 899 case OPN_RJCT: 900 case CNF_RJCT: 901 case CLS_ACPT: 902 mesh_plink_close(sdata, sta, event); 903 action = WLAN_SP_MESH_PEERING_CLOSE; 904 break; 905 case OPN_ACPT: 906 /* retry timer is left untouched */ 907 sta->mesh->plink_state = NL80211_PLINK_OPN_RCVD; 908 action = WLAN_SP_MESH_PEERING_CONFIRM; 909 break; 910 case CNF_ACPT: 911 sta->mesh->plink_state = NL80211_PLINK_CNF_RCVD; 912 mod_plink_timer(sta, mshcfg->dot11MeshConfirmTimeout); 913 break; 914 default: 915 break; 916 } 917 break; 918 case NL80211_PLINK_OPN_RCVD: 919 switch (event) { 920 case OPN_RJCT: 921 case CNF_RJCT: 922 case CLS_ACPT: 923 mesh_plink_close(sdata, sta, event); 924 action = WLAN_SP_MESH_PEERING_CLOSE; 925 break; 926 case OPN_ACPT: 927 action = WLAN_SP_MESH_PEERING_CONFIRM; 928 break; 929 case CNF_ACPT: 930 changed |= mesh_plink_establish(sdata, sta); 931 break; 932 default: 933 break; 934 } 935 break; 936 case NL80211_PLINK_CNF_RCVD: 937 switch (event) { 938 case OPN_RJCT: 939 case CNF_RJCT: 940 case CLS_ACPT: 941 mesh_plink_close(sdata, sta, event); 942 action = WLAN_SP_MESH_PEERING_CLOSE; 943 break; 944 case OPN_ACPT: 945 changed |= mesh_plink_establish(sdata, sta); 946 action = WLAN_SP_MESH_PEERING_CONFIRM; 947 break; 948 default: 949 break; 950 } 951 break; 952 case NL80211_PLINK_ESTAB: 953 switch (event) { 954 case CLS_ACPT: 955 changed |= __mesh_plink_deactivate(sta); 956 changed |= mesh_set_ht_prot_mode(sdata); 957 changed |= mesh_set_short_slot_time(sdata); 958 mesh_plink_close(sdata, sta, event); 959 action = WLAN_SP_MESH_PEERING_CLOSE; 960 flush = true; 961 break; 962 case OPN_ACPT: 963 action = WLAN_SP_MESH_PEERING_CONFIRM; 964 break; 965 default: 966 break; 967 } 968 break; 969 case NL80211_PLINK_HOLDING: 970 switch (event) { 971 case CLS_ACPT: 972 del_timer(&sta->mesh->plink_timer); 973 mesh_plink_fsm_restart(sta); 974 break; 975 case OPN_ACPT: 976 case CNF_ACPT: 977 case OPN_RJCT: 978 case CNF_RJCT: 979 action = WLAN_SP_MESH_PEERING_CLOSE; 980 break; 981 default: 982 break; 983 } 984 break; 985 default: 986 /* should not get here, PLINK_BLOCKED is dealt with at the 987 * beginning of the function 988 */ 989 break; 990 } 991 spin_unlock_bh(&sta->mesh->plink_lock); 992 if (flush) 993 mesh_path_flush_by_nexthop(sta); 994 if (action) { 995 mesh_plink_frame_tx(sdata, sta, action, sta->sta.addr, 996 sta->mesh->llid, sta->mesh->plid, 997 sta->mesh->reason); 998 999 /* also send confirm in open case */ 1000 if (action == WLAN_SP_MESH_PEERING_OPEN) { 1001 mesh_plink_frame_tx(sdata, sta, 1002 WLAN_SP_MESH_PEERING_CONFIRM, 1003 sta->sta.addr, sta->mesh->llid, 1004 sta->mesh->plid, 0); 1005 } 1006 } 1007 1008 return changed; 1009 } 1010 1011 /* 1012 * mesh_plink_get_event - get correct MPM event 1013 * 1014 * @sdata: interface 1015 * @sta: peer, leave NULL if processing a frame from a new suitable peer 1016 * @elems: peering management IEs 1017 * @ftype: frame type 1018 * @llid: peer's peer link ID 1019 * @plid: peer's local link ID 1020 * 1021 * Return: new peering event for @sta, but PLINK_UNDEFINED should be treated as 1022 * an error. 1023 */ 1024 static enum plink_event 1025 mesh_plink_get_event(struct ieee80211_sub_if_data *sdata, 1026 struct sta_info *sta, 1027 struct ieee802_11_elems *elems, 1028 enum ieee80211_self_protected_actioncode ftype, 1029 u16 llid, u16 plid) 1030 { 1031 enum plink_event event = PLINK_UNDEFINED; 1032 u8 ie_len = elems->peering_len; 1033 bool matches_local; 1034 1035 matches_local = (ftype == WLAN_SP_MESH_PEERING_CLOSE || 1036 mesh_matches_local(sdata, elems)); 1037 1038 /* deny open request from non-matching peer */ 1039 if (!matches_local && !sta) { 1040 event = OPN_RJCT; 1041 goto out; 1042 } 1043 1044 if (!sta) { 1045 if (ftype != WLAN_SP_MESH_PEERING_OPEN) { 1046 mpl_dbg(sdata, "Mesh plink: cls or cnf from unknown peer\n"); 1047 goto out; 1048 } 1049 /* ftype == WLAN_SP_MESH_PEERING_OPEN */ 1050 if (!mesh_plink_free_count(sdata)) { 1051 mpl_dbg(sdata, "Mesh plink error: no more free plinks\n"); 1052 goto out; 1053 } 1054 1055 /* new matching peer */ 1056 event = OPN_ACPT; 1057 goto out; 1058 } else { 1059 if (!test_sta_flag(sta, WLAN_STA_AUTH)) { 1060 mpl_dbg(sdata, "Mesh plink: Action frame from non-authed peer\n"); 1061 goto out; 1062 } 1063 if (sta->mesh->plink_state == NL80211_PLINK_BLOCKED) 1064 goto out; 1065 } 1066 1067 switch (ftype) { 1068 case WLAN_SP_MESH_PEERING_OPEN: 1069 if (!matches_local) 1070 event = OPN_RJCT; 1071 if (!mesh_plink_free_count(sdata) || 1072 (sta->mesh->plid && sta->mesh->plid != plid)) 1073 event = OPN_IGNR; 1074 else 1075 event = OPN_ACPT; 1076 break; 1077 case WLAN_SP_MESH_PEERING_CONFIRM: 1078 if (!matches_local) 1079 event = CNF_RJCT; 1080 if (!mesh_plink_free_count(sdata) || 1081 sta->mesh->llid != llid || 1082 (sta->mesh->plid && sta->mesh->plid != plid)) 1083 event = CNF_IGNR; 1084 else 1085 event = CNF_ACPT; 1086 break; 1087 case WLAN_SP_MESH_PEERING_CLOSE: 1088 if (sta->mesh->plink_state == NL80211_PLINK_ESTAB) 1089 /* Do not check for llid or plid. This does not 1090 * follow the standard but since multiple plinks 1091 * per sta are not supported, it is necessary in 1092 * order to avoid a livelock when MP A sees an 1093 * establish peer link to MP B but MP B does not 1094 * see it. This can be caused by a timeout in 1095 * B's peer link establishment or B beign 1096 * restarted. 1097 */ 1098 event = CLS_ACPT; 1099 else if (sta->mesh->plid != plid) 1100 event = CLS_IGNR; 1101 else if (ie_len == 8 && sta->mesh->llid != llid) 1102 event = CLS_IGNR; 1103 else 1104 event = CLS_ACPT; 1105 break; 1106 default: 1107 mpl_dbg(sdata, "Mesh plink: unknown frame subtype\n"); 1108 break; 1109 } 1110 1111 out: 1112 return event; 1113 } 1114 1115 static void 1116 mesh_process_plink_frame(struct ieee80211_sub_if_data *sdata, 1117 struct ieee80211_mgmt *mgmt, 1118 struct ieee802_11_elems *elems, 1119 struct ieee80211_rx_status *rx_status) 1120 { 1121 1122 struct sta_info *sta; 1123 enum plink_event event; 1124 enum ieee80211_self_protected_actioncode ftype; 1125 u64 changed = 0; 1126 u8 ie_len = elems->peering_len; 1127 u16 plid, llid = 0; 1128 1129 if (!elems->peering) { 1130 mpl_dbg(sdata, 1131 "Mesh plink: missing necessary peer link ie\n"); 1132 return; 1133 } 1134 1135 if (elems->rsn_len && 1136 sdata->u.mesh.security == IEEE80211_MESH_SEC_NONE) { 1137 mpl_dbg(sdata, 1138 "Mesh plink: can't establish link with secure peer\n"); 1139 return; 1140 } 1141 1142 ftype = mgmt->u.action.u.self_prot.action_code; 1143 if ((ftype == WLAN_SP_MESH_PEERING_OPEN && ie_len != 4) || 1144 (ftype == WLAN_SP_MESH_PEERING_CONFIRM && ie_len != 6) || 1145 (ftype == WLAN_SP_MESH_PEERING_CLOSE && ie_len != 6 1146 && ie_len != 8)) { 1147 mpl_dbg(sdata, 1148 "Mesh plink: incorrect plink ie length %d %d\n", 1149 ftype, ie_len); 1150 return; 1151 } 1152 1153 if (ftype != WLAN_SP_MESH_PEERING_CLOSE && 1154 (!elems->mesh_id || !elems->mesh_config)) { 1155 mpl_dbg(sdata, "Mesh plink: missing necessary ie\n"); 1156 return; 1157 } 1158 /* Note the lines below are correct, the llid in the frame is the plid 1159 * from the point of view of this host. 1160 */ 1161 plid = get_unaligned_le16(PLINK_GET_LLID(elems->peering)); 1162 if (ftype == WLAN_SP_MESH_PEERING_CONFIRM || 1163 (ftype == WLAN_SP_MESH_PEERING_CLOSE && ie_len == 8)) 1164 llid = get_unaligned_le16(PLINK_GET_PLID(elems->peering)); 1165 1166 /* WARNING: Only for sta pointer, is dropped & re-acquired */ 1167 rcu_read_lock(); 1168 1169 sta = sta_info_get(sdata, mgmt->sa); 1170 1171 if (ftype == WLAN_SP_MESH_PEERING_OPEN && 1172 !rssi_threshold_check(sdata, sta)) { 1173 mpl_dbg(sdata, "Mesh plink: %pM does not meet rssi threshold\n", 1174 mgmt->sa); 1175 goto unlock_rcu; 1176 } 1177 1178 /* Now we will figure out the appropriate event... */ 1179 event = mesh_plink_get_event(sdata, sta, elems, ftype, llid, plid); 1180 1181 if (event == OPN_ACPT) { 1182 rcu_read_unlock(); 1183 /* allocate sta entry if necessary and update info */ 1184 sta = mesh_sta_info_get(sdata, mgmt->sa, elems, rx_status); 1185 if (!sta) { 1186 mpl_dbg(sdata, "Mesh plink: failed to init peer!\n"); 1187 goto unlock_rcu; 1188 } 1189 sta->mesh->plid = plid; 1190 } else if (!sta && event == OPN_RJCT) { 1191 mesh_plink_frame_tx(sdata, NULL, WLAN_SP_MESH_PEERING_CLOSE, 1192 mgmt->sa, 0, plid, 1193 WLAN_REASON_MESH_CONFIG); 1194 goto unlock_rcu; 1195 } else if (!sta || event == PLINK_UNDEFINED) { 1196 /* something went wrong */ 1197 goto unlock_rcu; 1198 } 1199 1200 if (event == CNF_ACPT) { 1201 /* 802.11-2012 13.3.7.2 - update plid on CNF if not set */ 1202 if (!sta->mesh->plid) 1203 sta->mesh->plid = plid; 1204 1205 sta->mesh->aid = get_unaligned_le16(PLINK_CNF_AID(mgmt)); 1206 } 1207 1208 changed |= mesh_plink_fsm(sdata, sta, event); 1209 1210 unlock_rcu: 1211 rcu_read_unlock(); 1212 1213 if (changed) 1214 ieee80211_mbss_info_change_notify(sdata, changed); 1215 } 1216 1217 void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata, 1218 struct ieee80211_mgmt *mgmt, size_t len, 1219 struct ieee80211_rx_status *rx_status) 1220 { 1221 struct ieee802_11_elems *elems; 1222 size_t baselen; 1223 u8 *baseaddr; 1224 1225 /* need action_code, aux */ 1226 if (len < IEEE80211_MIN_ACTION_SIZE + 3) 1227 return; 1228 1229 if (sdata->u.mesh.user_mpm) 1230 /* userspace must register for these */ 1231 return; 1232 1233 if (is_multicast_ether_addr(mgmt->da)) { 1234 mpl_dbg(sdata, 1235 "Mesh plink: ignore frame from multicast address\n"); 1236 return; 1237 } 1238 1239 baseaddr = mgmt->u.action.u.self_prot.variable; 1240 baselen = (u8 *) mgmt->u.action.u.self_prot.variable - (u8 *) mgmt; 1241 if (mgmt->u.action.u.self_prot.action_code == 1242 WLAN_SP_MESH_PEERING_CONFIRM) { 1243 baseaddr += 4; 1244 baselen += 4; 1245 1246 if (baselen > len) 1247 return; 1248 } 1249 elems = ieee802_11_parse_elems(baseaddr, len - baselen, true, NULL); 1250 mesh_process_plink_frame(sdata, mgmt, elems, rx_status); 1251 kfree(elems); 1252 } 1253