mesh_plink.c revision 466f310d100ff54f346c1be481af9935c42467b3
1/* 2 * Copyright (c) 2008, 2009 open80211s Ltd. 3 * Author: Luis Carlos Cobo <luisca@cozybit.com> 4 * 5 * This program is free software; you can redistribute it and/or modify 6 * it under the terms of the GNU General Public License version 2 as 7 * published by the Free Software Foundation. 8 */ 9#include <linux/gfp.h> 10#include <linux/kernel.h> 11#include <linux/random.h> 12#include "ieee80211_i.h" 13#include "rate.h" 14#include "mesh.h" 15 16#define PLINK_GET_LLID(p) (p + 2) 17#define PLINK_GET_PLID(p) (p + 4) 18 19#define mod_plink_timer(s, t) (mod_timer(&s->plink_timer, \ 20 jiffies + HZ * t / 1000)) 21 22#define dot11MeshMaxRetries(s) (s->u.mesh.mshcfg.dot11MeshMaxRetries) 23#define dot11MeshRetryTimeout(s) (s->u.mesh.mshcfg.dot11MeshRetryTimeout) 24#define dot11MeshConfirmTimeout(s) (s->u.mesh.mshcfg.dot11MeshConfirmTimeout) 25#define dot11MeshHoldingTimeout(s) (s->u.mesh.mshcfg.dot11MeshHoldingTimeout) 26#define dot11MeshMaxPeerLinks(s) (s->u.mesh.mshcfg.dot11MeshMaxPeerLinks) 27 28/* We only need a valid sta if user configured a minimum rssi_threshold. */ 29#define rssi_threshold_check(sta, sdata) \ 30 (sdata->u.mesh.mshcfg.rssi_threshold == 0 ||\ 31 (sta && (s8) -ewma_read(&sta->avg_signal) > \ 32 sdata->u.mesh.mshcfg.rssi_threshold)) 33 34enum plink_event { 35 PLINK_UNDEFINED, 36 OPN_ACPT, 37 OPN_RJCT, 38 OPN_IGNR, 39 CNF_ACPT, 40 CNF_RJCT, 41 CNF_IGNR, 42 CLS_ACPT, 43 CLS_IGNR 44}; 45 46static int mesh_plink_frame_tx(struct ieee80211_sub_if_data *sdata, 47 enum ieee80211_self_protected_actioncode action, 48 u8 *da, __le16 llid, __le16 plid, __le16 reason); 49 50static inline 51void mesh_plink_inc_estab_count(struct ieee80211_sub_if_data *sdata) 52{ 53 atomic_inc(&sdata->u.mesh.mshstats.estab_plinks); 54 mesh_accept_plinks_update(sdata); 55} 56 57static inline 58void mesh_plink_dec_estab_count(struct ieee80211_sub_if_data *sdata) 59{ 60 atomic_dec(&sdata->u.mesh.mshstats.estab_plinks); 61 mesh_accept_plinks_update(sdata); 62} 63 64/** 65 * mesh_plink_fsm_restart - restart a mesh peer link finite state machine 66 * 67 * @sta: mesh peer link to restart 68 * 69 * Locking: this function must be called holding sta->lock 70 */ 71static inline void mesh_plink_fsm_restart(struct sta_info *sta) 72{ 73 sta->plink_state = NL80211_PLINK_LISTEN; 74 sta->llid = sta->plid = sta->reason = 0; 75 sta->plink_retries = 0; 76} 77 78/* 79 * Allocate mesh sta entry and insert into station table 80 */ 81static struct sta_info *mesh_plink_alloc(struct ieee80211_sub_if_data *sdata, 82 u8 *hw_addr) 83{ 84 struct sta_info *sta; 85 86 if (sdata->local->num_sta >= MESH_MAX_PLINKS) 87 return NULL; 88 89 sta = sta_info_alloc(sdata, hw_addr, GFP_KERNEL); 90 if (!sta) 91 return NULL; 92 93 sta_info_pre_move_state(sta, IEEE80211_STA_AUTH); 94 sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC); 95 sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED); 96 97 set_sta_flag(sta, WLAN_STA_WME); 98 99 return sta; 100} 101 102/** 103 * mesh_set_ht_prot_mode - set correct HT protection mode 104 * 105 * Section 9.23.3.5 of IEEE 80211-2012 describes the protection rules for HT 106 * mesh STA in a MBSS. Three HT protection modes are supported for now, non-HT 107 * mixed mode, 20MHz-protection and no-protection mode. non-HT mixed mode is 108 * selected if any non-HT peers are present in our MBSS. 20MHz-protection mode 109 * is selected if all peers in our 20/40MHz MBSS support HT and atleast one 110 * HT20 peer is present. Otherwise no-protection mode is selected. 111 */ 112static u32 mesh_set_ht_prot_mode(struct ieee80211_sub_if_data *sdata) 113{ 114 struct ieee80211_local *local = sdata->local; 115 struct sta_info *sta; 116 u32 changed = 0; 117 u16 ht_opmode; 118 bool non_ht_sta = false, ht20_sta = false; 119 120 if (sdata->vif.bss_conf.channel_type == NL80211_CHAN_NO_HT) 121 return 0; 122 123 rcu_read_lock(); 124 list_for_each_entry_rcu(sta, &local->sta_list, list) { 125 if (sdata != sta->sdata || 126 sta->plink_state != NL80211_PLINK_ESTAB) 127 continue; 128 129 switch (sta->ch_type) { 130 case NL80211_CHAN_NO_HT: 131 mpl_dbg(sdata, 132 "mesh_plink %pM: nonHT sta (%pM) is present\n", 133 sdata->vif.addr, sta->sta.addr); 134 non_ht_sta = true; 135 goto out; 136 case NL80211_CHAN_HT20: 137 mpl_dbg(sdata, 138 "mesh_plink %pM: HT20 sta (%pM) is present\n", 139 sdata->vif.addr, sta->sta.addr); 140 ht20_sta = true; 141 default: 142 break; 143 } 144 } 145out: 146 rcu_read_unlock(); 147 148 if (non_ht_sta) 149 ht_opmode = IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED; 150 else if (ht20_sta && 151 sdata->vif.bss_conf.channel_type > NL80211_CHAN_HT20) 152 ht_opmode = IEEE80211_HT_OP_MODE_PROTECTION_20MHZ; 153 else 154 ht_opmode = IEEE80211_HT_OP_MODE_PROTECTION_NONE; 155 156 if (sdata->vif.bss_conf.ht_operation_mode != ht_opmode) { 157 sdata->vif.bss_conf.ht_operation_mode = ht_opmode; 158 sdata->u.mesh.mshcfg.ht_opmode = ht_opmode; 159 changed = BSS_CHANGED_HT; 160 mpl_dbg(sdata, 161 "mesh_plink %pM: protection mode changed to %d\n", 162 sdata->vif.addr, ht_opmode); 163 } 164 165 return changed; 166} 167 168/** 169 * __mesh_plink_deactivate - deactivate mesh peer link 170 * 171 * @sta: mesh peer link to deactivate 172 * 173 * All mesh paths with this peer as next hop will be flushed 174 * 175 * Locking: the caller must hold sta->lock 176 */ 177static bool __mesh_plink_deactivate(struct sta_info *sta) 178{ 179 struct ieee80211_sub_if_data *sdata = sta->sdata; 180 bool deactivated = false; 181 182 if (sta->plink_state == NL80211_PLINK_ESTAB) { 183 mesh_plink_dec_estab_count(sdata); 184 deactivated = true; 185 } 186 sta->plink_state = NL80211_PLINK_BLOCKED; 187 mesh_path_flush_by_nexthop(sta); 188 189 return deactivated; 190} 191 192/** 193 * mesh_plink_deactivate - deactivate mesh peer link 194 * 195 * @sta: mesh peer link to deactivate 196 * 197 * All mesh paths with this peer as next hop will be flushed 198 */ 199void mesh_plink_deactivate(struct sta_info *sta) 200{ 201 struct ieee80211_sub_if_data *sdata = sta->sdata; 202 bool deactivated; 203 204 spin_lock_bh(&sta->lock); 205 deactivated = __mesh_plink_deactivate(sta); 206 sta->reason = cpu_to_le16(WLAN_REASON_MESH_PEER_CANCELED); 207 mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_CLOSE, 208 sta->sta.addr, sta->llid, sta->plid, 209 sta->reason); 210 spin_unlock_bh(&sta->lock); 211 212 if (deactivated) 213 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON); 214} 215 216static int mesh_plink_frame_tx(struct ieee80211_sub_if_data *sdata, 217 enum ieee80211_self_protected_actioncode action, 218 u8 *da, __le16 llid, __le16 plid, __le16 reason) { 219 struct ieee80211_local *local = sdata->local; 220 struct sk_buff *skb; 221 struct ieee80211_tx_info *info; 222 struct ieee80211_mgmt *mgmt; 223 bool include_plid = false; 224 u16 peering_proto = 0; 225 u8 *pos, ie_len = 4; 226 int hdr_len = offsetof(struct ieee80211_mgmt, u.action.u.self_prot) + 227 sizeof(mgmt->u.action.u.self_prot); 228 int err = -ENOMEM; 229 230 skb = dev_alloc_skb(local->tx_headroom + 231 hdr_len + 232 2 + /* capability info */ 233 2 + /* AID */ 234 2 + 8 + /* supported rates */ 235 2 + (IEEE80211_MAX_SUPP_RATES - 8) + 236 2 + sdata->u.mesh.mesh_id_len + 237 2 + sizeof(struct ieee80211_meshconf_ie) + 238 2 + sizeof(struct ieee80211_ht_cap) + 239 2 + sizeof(struct ieee80211_ht_operation) + 240 2 + 8 + /* peering IE */ 241 sdata->u.mesh.ie_len); 242 if (!skb) 243 return -1; 244 info = IEEE80211_SKB_CB(skb); 245 skb_reserve(skb, local->tx_headroom); 246 mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len); 247 memset(mgmt, 0, hdr_len); 248 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 249 IEEE80211_STYPE_ACTION); 250 memcpy(mgmt->da, da, ETH_ALEN); 251 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN); 252 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN); 253 mgmt->u.action.category = WLAN_CATEGORY_SELF_PROTECTED; 254 mgmt->u.action.u.self_prot.action_code = action; 255 256 if (action != WLAN_SP_MESH_PEERING_CLOSE) { 257 /* capability info */ 258 pos = skb_put(skb, 2); 259 memset(pos, 0, 2); 260 if (action == WLAN_SP_MESH_PEERING_CONFIRM) { 261 /* AID */ 262 pos = skb_put(skb, 2); 263 memcpy(pos + 2, &plid, 2); 264 } 265 if (ieee80211_add_srates_ie(sdata, skb, true, 266 local->oper_channel->band) || 267 ieee80211_add_ext_srates_ie(sdata, skb, true, 268 local->oper_channel->band) || 269 mesh_add_rsn_ie(skb, sdata) || 270 mesh_add_meshid_ie(skb, sdata) || 271 mesh_add_meshconf_ie(skb, sdata)) 272 goto free; 273 } else { /* WLAN_SP_MESH_PEERING_CLOSE */ 274 info->flags |= IEEE80211_TX_CTL_NO_ACK; 275 if (mesh_add_meshid_ie(skb, sdata)) 276 goto free; 277 } 278 279 /* Add Mesh Peering Management element */ 280 switch (action) { 281 case WLAN_SP_MESH_PEERING_OPEN: 282 break; 283 case WLAN_SP_MESH_PEERING_CONFIRM: 284 ie_len += 2; 285 include_plid = true; 286 break; 287 case WLAN_SP_MESH_PEERING_CLOSE: 288 if (plid) { 289 ie_len += 2; 290 include_plid = true; 291 } 292 ie_len += 2; /* reason code */ 293 break; 294 default: 295 err = -EINVAL; 296 goto free; 297 } 298 299 if (WARN_ON(skb_tailroom(skb) < 2 + ie_len)) 300 goto free; 301 302 pos = skb_put(skb, 2 + ie_len); 303 *pos++ = WLAN_EID_PEER_MGMT; 304 *pos++ = ie_len; 305 memcpy(pos, &peering_proto, 2); 306 pos += 2; 307 memcpy(pos, &llid, 2); 308 pos += 2; 309 if (include_plid) { 310 memcpy(pos, &plid, 2); 311 pos += 2; 312 } 313 if (action == WLAN_SP_MESH_PEERING_CLOSE) { 314 memcpy(pos, &reason, 2); 315 pos += 2; 316 } 317 318 if (action != WLAN_SP_MESH_PEERING_CLOSE) { 319 if (mesh_add_ht_cap_ie(skb, sdata) || 320 mesh_add_ht_oper_ie(skb, sdata)) 321 goto free; 322 } 323 324 if (mesh_add_vendor_ies(skb, sdata)) 325 goto free; 326 327 ieee80211_tx_skb(sdata, skb); 328 return 0; 329free: 330 kfree_skb(skb); 331 return err; 332} 333 334/** 335 * mesh_peer_init - initialize new mesh peer and return resulting sta_info 336 * 337 * @sdata: local meshif 338 * @addr: peer's address 339 * @elems: IEs from beacon or mesh peering frame 340 * 341 * call under RCU 342 */ 343static struct sta_info *mesh_peer_init(struct ieee80211_sub_if_data *sdata, 344 u8 *addr, 345 struct ieee802_11_elems *elems) 346{ 347 struct ieee80211_local *local = sdata->local; 348 enum ieee80211_band band = local->oper_channel->band; 349 struct ieee80211_supported_band *sband; 350 u32 rates, basic_rates = 0; 351 struct sta_info *sta; 352 bool insert = false; 353 354 sband = local->hw.wiphy->bands[band]; 355 rates = ieee80211_sta_get_rates(local, elems, band, &basic_rates); 356 357 sta = sta_info_get(sdata, addr); 358 if (!sta) { 359 /* Userspace handles peer allocation when security is enabled */ 360 if (sdata->u.mesh.security & IEEE80211_MESH_SEC_AUTHED) { 361 cfg80211_notify_new_peer_candidate(sdata->dev, addr, 362 elems->ie_start, 363 elems->total_len, 364 GFP_ATOMIC); 365 return NULL; 366 } 367 368 sta = mesh_plink_alloc(sdata, addr); 369 if (!sta) 370 return NULL; 371 insert = true; 372 } 373 374 spin_lock_bh(&sta->lock); 375 sta->last_rx = jiffies; 376 if (sta->plink_state == NL80211_PLINK_ESTAB) { 377 spin_unlock_bh(&sta->lock); 378 return sta; 379 } 380 381 sta->sta.supp_rates[band] = rates; 382 if (elems->ht_cap_elem && 383 sdata->vif.bss_conf.channel_type != NL80211_CHAN_NO_HT) 384 ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband, 385 elems->ht_cap_elem, 386 &sta->sta.ht_cap); 387 else 388 memset(&sta->sta.ht_cap, 0, sizeof(sta->sta.ht_cap)); 389 390 if (elems->ht_operation) { 391 if (!(elems->ht_operation->ht_param & 392 IEEE80211_HT_PARAM_CHAN_WIDTH_ANY)) 393 sta->sta.ht_cap.cap &= 394 ~IEEE80211_HT_CAP_SUP_WIDTH_20_40; 395 sta->ch_type = 396 ieee80211_ht_oper_to_channel_type(elems->ht_operation); 397 } 398 399 rate_control_rate_init(sta); 400 spin_unlock_bh(&sta->lock); 401 402 if (insert && sta_info_insert(sta)) 403 return NULL; 404 405 return sta; 406} 407 408void mesh_neighbour_update(struct ieee80211_sub_if_data *sdata, 409 u8 *hw_addr, 410 struct ieee802_11_elems *elems) 411{ 412 struct sta_info *sta; 413 414 rcu_read_lock(); 415 sta = mesh_peer_init(sdata, hw_addr, elems); 416 if (!sta) 417 goto out; 418 419 if (mesh_peer_accepts_plinks(elems) && 420 sta->plink_state == NL80211_PLINK_LISTEN && 421 sdata->u.mesh.accepting_plinks && 422 sdata->u.mesh.mshcfg.auto_open_plinks && 423 rssi_threshold_check(sta, sdata)) 424 mesh_plink_open(sta); 425 426out: 427 rcu_read_unlock(); 428} 429 430static void mesh_plink_timer(unsigned long data) 431{ 432 struct sta_info *sta; 433 __le16 llid, plid, reason; 434 struct ieee80211_sub_if_data *sdata; 435 436 /* 437 * This STA is valid because sta_info_destroy() will 438 * del_timer_sync() this timer after having made sure 439 * it cannot be readded (by deleting the plink.) 440 */ 441 sta = (struct sta_info *) data; 442 443 if (sta->sdata->local->quiescing) { 444 sta->plink_timer_was_running = true; 445 return; 446 } 447 448 spin_lock_bh(&sta->lock); 449 if (sta->ignore_plink_timer) { 450 sta->ignore_plink_timer = false; 451 spin_unlock_bh(&sta->lock); 452 return; 453 } 454 mpl_dbg(sta->sdata, 455 "Mesh plink timer for %pM fired on state %d\n", 456 sta->sta.addr, sta->plink_state); 457 reason = 0; 458 llid = sta->llid; 459 plid = sta->plid; 460 sdata = sta->sdata; 461 462 switch (sta->plink_state) { 463 case NL80211_PLINK_OPN_RCVD: 464 case NL80211_PLINK_OPN_SNT: 465 /* retry timer */ 466 if (sta->plink_retries < dot11MeshMaxRetries(sdata)) { 467 u32 rand; 468 mpl_dbg(sta->sdata, 469 "Mesh plink for %pM (retry, timeout): %d %d\n", 470 sta->sta.addr, sta->plink_retries, 471 sta->plink_timeout); 472 get_random_bytes(&rand, sizeof(u32)); 473 sta->plink_timeout = sta->plink_timeout + 474 rand % sta->plink_timeout; 475 ++sta->plink_retries; 476 mod_plink_timer(sta, sta->plink_timeout); 477 spin_unlock_bh(&sta->lock); 478 mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_OPEN, 479 sta->sta.addr, llid, 0, 0); 480 break; 481 } 482 reason = cpu_to_le16(WLAN_REASON_MESH_MAX_RETRIES); 483 /* fall through on else */ 484 case NL80211_PLINK_CNF_RCVD: 485 /* confirm timer */ 486 if (!reason) 487 reason = cpu_to_le16(WLAN_REASON_MESH_CONFIRM_TIMEOUT); 488 sta->plink_state = NL80211_PLINK_HOLDING; 489 mod_plink_timer(sta, dot11MeshHoldingTimeout(sdata)); 490 spin_unlock_bh(&sta->lock); 491 mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_CLOSE, 492 sta->sta.addr, llid, plid, reason); 493 break; 494 case NL80211_PLINK_HOLDING: 495 /* holding timer */ 496 del_timer(&sta->plink_timer); 497 mesh_plink_fsm_restart(sta); 498 spin_unlock_bh(&sta->lock); 499 break; 500 default: 501 spin_unlock_bh(&sta->lock); 502 break; 503 } 504} 505 506#ifdef CONFIG_PM 507void mesh_plink_quiesce(struct sta_info *sta) 508{ 509 if (del_timer_sync(&sta->plink_timer)) 510 sta->plink_timer_was_running = true; 511} 512 513void mesh_plink_restart(struct sta_info *sta) 514{ 515 if (sta->plink_timer_was_running) { 516 add_timer(&sta->plink_timer); 517 sta->plink_timer_was_running = false; 518 } 519} 520#endif 521 522static inline void mesh_plink_timer_set(struct sta_info *sta, int timeout) 523{ 524 sta->plink_timer.expires = jiffies + (HZ * timeout / 1000); 525 sta->plink_timer.data = (unsigned long) sta; 526 sta->plink_timer.function = mesh_plink_timer; 527 sta->plink_timeout = timeout; 528 add_timer(&sta->plink_timer); 529} 530 531int mesh_plink_open(struct sta_info *sta) 532{ 533 __le16 llid; 534 struct ieee80211_sub_if_data *sdata = sta->sdata; 535 536 if (!test_sta_flag(sta, WLAN_STA_AUTH)) 537 return -EPERM; 538 539 spin_lock_bh(&sta->lock); 540 get_random_bytes(&llid, 2); 541 sta->llid = llid; 542 if (sta->plink_state != NL80211_PLINK_LISTEN) { 543 spin_unlock_bh(&sta->lock); 544 return -EBUSY; 545 } 546 sta->plink_state = NL80211_PLINK_OPN_SNT; 547 mesh_plink_timer_set(sta, dot11MeshRetryTimeout(sdata)); 548 spin_unlock_bh(&sta->lock); 549 mpl_dbg(sdata, 550 "Mesh plink: starting establishment with %pM\n", 551 sta->sta.addr); 552 553 return mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_OPEN, 554 sta->sta.addr, llid, 0, 0); 555} 556 557void mesh_plink_block(struct sta_info *sta) 558{ 559 struct ieee80211_sub_if_data *sdata = sta->sdata; 560 bool deactivated; 561 562 spin_lock_bh(&sta->lock); 563 deactivated = __mesh_plink_deactivate(sta); 564 sta->plink_state = NL80211_PLINK_BLOCKED; 565 spin_unlock_bh(&sta->lock); 566 567 if (deactivated) 568 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON); 569} 570 571 572void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata, struct ieee80211_mgmt *mgmt, 573 size_t len, struct ieee80211_rx_status *rx_status) 574{ 575 struct ieee802_11_elems elems; 576 struct sta_info *sta; 577 enum plink_event event; 578 enum ieee80211_self_protected_actioncode ftype; 579 size_t baselen; 580 bool matches_local = true; 581 u8 ie_len; 582 u8 *baseaddr; 583 u32 changed = 0; 584 __le16 plid, llid, reason; 585 static const char *mplstates[] = { 586 [NL80211_PLINK_LISTEN] = "LISTEN", 587 [NL80211_PLINK_OPN_SNT] = "OPN-SNT", 588 [NL80211_PLINK_OPN_RCVD] = "OPN-RCVD", 589 [NL80211_PLINK_CNF_RCVD] = "CNF_RCVD", 590 [NL80211_PLINK_ESTAB] = "ESTAB", 591 [NL80211_PLINK_HOLDING] = "HOLDING", 592 [NL80211_PLINK_BLOCKED] = "BLOCKED" 593 }; 594 595 /* need action_code, aux */ 596 if (len < IEEE80211_MIN_ACTION_SIZE + 3) 597 return; 598 599 if (is_multicast_ether_addr(mgmt->da)) { 600 mpl_dbg(sdata, 601 "Mesh plink: ignore frame from multicast address\n"); 602 return; 603 } 604 605 baseaddr = mgmt->u.action.u.self_prot.variable; 606 baselen = (u8 *) mgmt->u.action.u.self_prot.variable - (u8 *) mgmt; 607 if (mgmt->u.action.u.self_prot.action_code == 608 WLAN_SP_MESH_PEERING_CONFIRM) { 609 baseaddr += 4; 610 baselen += 4; 611 } 612 ieee802_11_parse_elems(baseaddr, len - baselen, &elems); 613 if (!elems.peering) { 614 mpl_dbg(sdata, 615 "Mesh plink: missing necessary peer link ie\n"); 616 return; 617 } 618 if (elems.rsn_len && 619 sdata->u.mesh.security == IEEE80211_MESH_SEC_NONE) { 620 mpl_dbg(sdata, 621 "Mesh plink: can't establish link with secure peer\n"); 622 return; 623 } 624 625 ftype = mgmt->u.action.u.self_prot.action_code; 626 ie_len = elems.peering_len; 627 if ((ftype == WLAN_SP_MESH_PEERING_OPEN && ie_len != 4) || 628 (ftype == WLAN_SP_MESH_PEERING_CONFIRM && ie_len != 6) || 629 (ftype == WLAN_SP_MESH_PEERING_CLOSE && ie_len != 6 630 && ie_len != 8)) { 631 mpl_dbg(sdata, 632 "Mesh plink: incorrect plink ie length %d %d\n", 633 ftype, ie_len); 634 return; 635 } 636 637 if (ftype != WLAN_SP_MESH_PEERING_CLOSE && 638 (!elems.mesh_id || !elems.mesh_config)) { 639 mpl_dbg(sdata, "Mesh plink: missing necessary ie\n"); 640 return; 641 } 642 /* Note the lines below are correct, the llid in the frame is the plid 643 * from the point of view of this host. 644 */ 645 memcpy(&plid, PLINK_GET_LLID(elems.peering), 2); 646 if (ftype == WLAN_SP_MESH_PEERING_CONFIRM || 647 (ftype == WLAN_SP_MESH_PEERING_CLOSE && ie_len == 8)) 648 memcpy(&llid, PLINK_GET_PLID(elems.peering), 2); 649 650 rcu_read_lock(); 651 652 sta = sta_info_get(sdata, mgmt->sa); 653 if (!sta && ftype != WLAN_SP_MESH_PEERING_OPEN) { 654 mpl_dbg(sdata, "Mesh plink: cls or cnf from unknown peer\n"); 655 rcu_read_unlock(); 656 return; 657 } 658 659 if (ftype == WLAN_SP_MESH_PEERING_OPEN && 660 !rssi_threshold_check(sta, sdata)) { 661 mpl_dbg(sdata, "Mesh plink: %pM does not meet rssi threshold\n", 662 mgmt->sa); 663 rcu_read_unlock(); 664 return; 665 } 666 667 if (sta && !test_sta_flag(sta, WLAN_STA_AUTH)) { 668 mpl_dbg(sdata, "Mesh plink: Action frame from non-authed peer\n"); 669 rcu_read_unlock(); 670 return; 671 } 672 673 if (sta && sta->plink_state == NL80211_PLINK_BLOCKED) { 674 rcu_read_unlock(); 675 return; 676 } 677 678 /* Now we will figure out the appropriate event... */ 679 event = PLINK_UNDEFINED; 680 if (ftype != WLAN_SP_MESH_PEERING_CLOSE && 681 !mesh_matches_local(sdata, &elems)) { 682 matches_local = false; 683 switch (ftype) { 684 case WLAN_SP_MESH_PEERING_OPEN: 685 event = OPN_RJCT; 686 break; 687 case WLAN_SP_MESH_PEERING_CONFIRM: 688 event = CNF_RJCT; 689 break; 690 default: 691 break; 692 } 693 } 694 695 if (!sta && !matches_local) { 696 rcu_read_unlock(); 697 reason = cpu_to_le16(WLAN_REASON_MESH_CONFIG); 698 llid = 0; 699 mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_CLOSE, 700 mgmt->sa, llid, plid, reason); 701 return; 702 } else if (!sta) { 703 /* ftype == WLAN_SP_MESH_PEERING_OPEN */ 704 if (!mesh_plink_free_count(sdata)) { 705 mpl_dbg(sdata, "Mesh plink error: no more free plinks\n"); 706 rcu_read_unlock(); 707 return; 708 } 709 event = OPN_ACPT; 710 } else if (matches_local) { 711 switch (ftype) { 712 case WLAN_SP_MESH_PEERING_OPEN: 713 if (!mesh_plink_free_count(sdata) || 714 (sta->plid && sta->plid != plid)) 715 event = OPN_IGNR; 716 else 717 event = OPN_ACPT; 718 break; 719 case WLAN_SP_MESH_PEERING_CONFIRM: 720 if (!mesh_plink_free_count(sdata) || 721 (sta->llid != llid || sta->plid != plid)) 722 event = CNF_IGNR; 723 else 724 event = CNF_ACPT; 725 break; 726 case WLAN_SP_MESH_PEERING_CLOSE: 727 if (sta->plink_state == NL80211_PLINK_ESTAB) 728 /* Do not check for llid or plid. This does not 729 * follow the standard but since multiple plinks 730 * per sta are not supported, it is necessary in 731 * order to avoid a livelock when MP A sees an 732 * establish peer link to MP B but MP B does not 733 * see it. This can be caused by a timeout in 734 * B's peer link establishment or B beign 735 * restarted. 736 */ 737 event = CLS_ACPT; 738 else if (sta->plid != plid) 739 event = CLS_IGNR; 740 else if (ie_len == 7 && sta->llid != llid) 741 event = CLS_IGNR; 742 else 743 event = CLS_ACPT; 744 break; 745 default: 746 mpl_dbg(sdata, "Mesh plink: unknown frame subtype\n"); 747 rcu_read_unlock(); 748 return; 749 } 750 } 751 752 if (event == OPN_ACPT) { 753 /* allocate sta entry if necessary and update info */ 754 sta = mesh_peer_init(sdata, mgmt->sa, &elems); 755 if (!sta) { 756 mpl_dbg(sdata, "Mesh plink: failed to init peer!\n"); 757 rcu_read_unlock(); 758 return; 759 } 760 } 761 762 mpl_dbg(sdata, 763 "Mesh plink (peer, state, llid, plid, event): %pM %s %d %d %d\n", 764 mgmt->sa, mplstates[sta->plink_state], 765 le16_to_cpu(sta->llid), le16_to_cpu(sta->plid), 766 event); 767 reason = 0; 768 spin_lock_bh(&sta->lock); 769 switch (sta->plink_state) { 770 /* spin_unlock as soon as state is updated at each case */ 771 case NL80211_PLINK_LISTEN: 772 switch (event) { 773 case CLS_ACPT: 774 mesh_plink_fsm_restart(sta); 775 spin_unlock_bh(&sta->lock); 776 break; 777 case OPN_ACPT: 778 sta->plink_state = NL80211_PLINK_OPN_RCVD; 779 sta->plid = plid; 780 get_random_bytes(&llid, 2); 781 sta->llid = llid; 782 mesh_plink_timer_set(sta, dot11MeshRetryTimeout(sdata)); 783 spin_unlock_bh(&sta->lock); 784 mesh_plink_frame_tx(sdata, 785 WLAN_SP_MESH_PEERING_OPEN, 786 sta->sta.addr, llid, 0, 0); 787 mesh_plink_frame_tx(sdata, 788 WLAN_SP_MESH_PEERING_CONFIRM, 789 sta->sta.addr, llid, plid, 0); 790 break; 791 default: 792 spin_unlock_bh(&sta->lock); 793 break; 794 } 795 break; 796 797 case NL80211_PLINK_OPN_SNT: 798 switch (event) { 799 case OPN_RJCT: 800 case CNF_RJCT: 801 reason = cpu_to_le16(WLAN_REASON_MESH_CONFIG); 802 case CLS_ACPT: 803 if (!reason) 804 reason = cpu_to_le16(WLAN_REASON_MESH_CLOSE); 805 sta->reason = reason; 806 sta->plink_state = NL80211_PLINK_HOLDING; 807 if (!mod_plink_timer(sta, 808 dot11MeshHoldingTimeout(sdata))) 809 sta->ignore_plink_timer = true; 810 811 llid = sta->llid; 812 spin_unlock_bh(&sta->lock); 813 mesh_plink_frame_tx(sdata, 814 WLAN_SP_MESH_PEERING_CLOSE, 815 sta->sta.addr, llid, plid, reason); 816 break; 817 case OPN_ACPT: 818 /* retry timer is left untouched */ 819 sta->plink_state = NL80211_PLINK_OPN_RCVD; 820 sta->plid = plid; 821 llid = sta->llid; 822 spin_unlock_bh(&sta->lock); 823 mesh_plink_frame_tx(sdata, 824 WLAN_SP_MESH_PEERING_CONFIRM, 825 sta->sta.addr, llid, plid, 0); 826 break; 827 case CNF_ACPT: 828 sta->plink_state = NL80211_PLINK_CNF_RCVD; 829 if (!mod_plink_timer(sta, 830 dot11MeshConfirmTimeout(sdata))) 831 sta->ignore_plink_timer = true; 832 833 spin_unlock_bh(&sta->lock); 834 break; 835 default: 836 spin_unlock_bh(&sta->lock); 837 break; 838 } 839 break; 840 841 case NL80211_PLINK_OPN_RCVD: 842 switch (event) { 843 case OPN_RJCT: 844 case CNF_RJCT: 845 reason = cpu_to_le16(WLAN_REASON_MESH_CONFIG); 846 case CLS_ACPT: 847 if (!reason) 848 reason = cpu_to_le16(WLAN_REASON_MESH_CLOSE); 849 sta->reason = reason; 850 sta->plink_state = NL80211_PLINK_HOLDING; 851 if (!mod_plink_timer(sta, 852 dot11MeshHoldingTimeout(sdata))) 853 sta->ignore_plink_timer = true; 854 855 llid = sta->llid; 856 spin_unlock_bh(&sta->lock); 857 mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_CLOSE, 858 sta->sta.addr, llid, plid, reason); 859 break; 860 case OPN_ACPT: 861 llid = sta->llid; 862 spin_unlock_bh(&sta->lock); 863 mesh_plink_frame_tx(sdata, 864 WLAN_SP_MESH_PEERING_CONFIRM, 865 sta->sta.addr, llid, plid, 0); 866 break; 867 case CNF_ACPT: 868 del_timer(&sta->plink_timer); 869 sta->plink_state = NL80211_PLINK_ESTAB; 870 spin_unlock_bh(&sta->lock); 871 mesh_plink_inc_estab_count(sdata); 872 changed |= mesh_set_ht_prot_mode(sdata); 873 changed |= BSS_CHANGED_BEACON; 874 mpl_dbg(sdata, "Mesh plink with %pM ESTABLISHED\n", 875 sta->sta.addr); 876 break; 877 default: 878 spin_unlock_bh(&sta->lock); 879 break; 880 } 881 break; 882 883 case NL80211_PLINK_CNF_RCVD: 884 switch (event) { 885 case OPN_RJCT: 886 case CNF_RJCT: 887 reason = cpu_to_le16(WLAN_REASON_MESH_CONFIG); 888 case CLS_ACPT: 889 if (!reason) 890 reason = cpu_to_le16(WLAN_REASON_MESH_CLOSE); 891 sta->reason = reason; 892 sta->plink_state = NL80211_PLINK_HOLDING; 893 if (!mod_plink_timer(sta, 894 dot11MeshHoldingTimeout(sdata))) 895 sta->ignore_plink_timer = true; 896 897 llid = sta->llid; 898 spin_unlock_bh(&sta->lock); 899 mesh_plink_frame_tx(sdata, 900 WLAN_SP_MESH_PEERING_CLOSE, 901 sta->sta.addr, llid, plid, reason); 902 break; 903 case OPN_ACPT: 904 del_timer(&sta->plink_timer); 905 sta->plink_state = NL80211_PLINK_ESTAB; 906 spin_unlock_bh(&sta->lock); 907 mesh_plink_inc_estab_count(sdata); 908 changed |= mesh_set_ht_prot_mode(sdata); 909 changed |= BSS_CHANGED_BEACON; 910 mpl_dbg(sdata, "Mesh plink with %pM ESTABLISHED\n", 911 sta->sta.addr); 912 mesh_plink_frame_tx(sdata, 913 WLAN_SP_MESH_PEERING_CONFIRM, 914 sta->sta.addr, llid, plid, 0); 915 break; 916 default: 917 spin_unlock_bh(&sta->lock); 918 break; 919 } 920 break; 921 922 case NL80211_PLINK_ESTAB: 923 switch (event) { 924 case CLS_ACPT: 925 reason = cpu_to_le16(WLAN_REASON_MESH_CLOSE); 926 sta->reason = reason; 927 __mesh_plink_deactivate(sta); 928 sta->plink_state = NL80211_PLINK_HOLDING; 929 llid = sta->llid; 930 mod_plink_timer(sta, dot11MeshHoldingTimeout(sdata)); 931 spin_unlock_bh(&sta->lock); 932 changed |= mesh_set_ht_prot_mode(sdata); 933 changed |= BSS_CHANGED_BEACON; 934 mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_CLOSE, 935 sta->sta.addr, llid, plid, reason); 936 break; 937 case OPN_ACPT: 938 llid = sta->llid; 939 spin_unlock_bh(&sta->lock); 940 mesh_plink_frame_tx(sdata, 941 WLAN_SP_MESH_PEERING_CONFIRM, 942 sta->sta.addr, llid, plid, 0); 943 break; 944 default: 945 spin_unlock_bh(&sta->lock); 946 break; 947 } 948 break; 949 case NL80211_PLINK_HOLDING: 950 switch (event) { 951 case CLS_ACPT: 952 if (del_timer(&sta->plink_timer)) 953 sta->ignore_plink_timer = 1; 954 mesh_plink_fsm_restart(sta); 955 spin_unlock_bh(&sta->lock); 956 break; 957 case OPN_ACPT: 958 case CNF_ACPT: 959 case OPN_RJCT: 960 case CNF_RJCT: 961 llid = sta->llid; 962 reason = sta->reason; 963 spin_unlock_bh(&sta->lock); 964 mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_CLOSE, 965 sta->sta.addr, llid, plid, reason); 966 break; 967 default: 968 spin_unlock_bh(&sta->lock); 969 } 970 break; 971 default: 972 /* should not get here, PLINK_BLOCKED is dealt with at the 973 * beginning of the function 974 */ 975 spin_unlock_bh(&sta->lock); 976 break; 977 } 978 979 rcu_read_unlock(); 980 981 if (changed) 982 ieee80211_bss_info_change_notify(sdata, changed); 983} 984