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 /* We only need a valid sta if user configured a minimum rssi_threshold. */ 23 #define rssi_threshold_check(sta, sdata) \ 24 (sdata->u.mesh.mshcfg.rssi_threshold == 0 ||\ 25 (sta && (s8) -ewma_read(&sta->avg_signal) > \ 26 sdata->u.mesh.mshcfg.rssi_threshold)) 27 28 enum plink_event { 29 PLINK_UNDEFINED, 30 OPN_ACPT, 31 OPN_RJCT, 32 OPN_IGNR, 33 CNF_ACPT, 34 CNF_RJCT, 35 CNF_IGNR, 36 CLS_ACPT, 37 CLS_IGNR 38 }; 39 40 static const char * const mplstates[] = { 41 [NL80211_PLINK_LISTEN] = "LISTEN", 42 [NL80211_PLINK_OPN_SNT] = "OPN-SNT", 43 [NL80211_PLINK_OPN_RCVD] = "OPN-RCVD", 44 [NL80211_PLINK_CNF_RCVD] = "CNF_RCVD", 45 [NL80211_PLINK_ESTAB] = "ESTAB", 46 [NL80211_PLINK_HOLDING] = "HOLDING", 47 [NL80211_PLINK_BLOCKED] = "BLOCKED" 48 }; 49 50 static const char * const mplevents[] = { 51 [PLINK_UNDEFINED] = "NONE", 52 [OPN_ACPT] = "OPN_ACPT", 53 [OPN_RJCT] = "OPN_RJCT", 54 [OPN_IGNR] = "OPN_IGNR", 55 [CNF_ACPT] = "CNF_ACPT", 56 [CNF_RJCT] = "CNF_RJCT", 57 [CNF_IGNR] = "CNF_IGNR", 58 [CLS_ACPT] = "CLS_ACPT", 59 [CLS_IGNR] = "CLS_IGNR" 60 }; 61 62 static int mesh_plink_frame_tx(struct ieee80211_sub_if_data *sdata, 63 enum ieee80211_self_protected_actioncode action, 64 u8 *da, __le16 llid, __le16 plid, __le16 reason); 65 66 /** 67 * mesh_plink_fsm_restart - restart a mesh peer link finite state machine 68 * 69 * @sta: mesh peer link to restart 70 * 71 * Locking: this function must be called holding sta->lock 72 */ 73 static inline void mesh_plink_fsm_restart(struct sta_info *sta) 74 { 75 sta->plink_state = NL80211_PLINK_LISTEN; 76 sta->llid = sta->plid = sta->reason = 0; 77 sta->plink_retries = 0; 78 } 79 80 /* 81 * mesh_set_short_slot_time - enable / disable ERP short slot time. 82 * 83 * The standard indirectly mandates mesh STAs to turn off short slot time by 84 * disallowing advertising this (802.11-2012 8.4.1.4), but that doesn't mean we 85 * can't be sneaky about it. Enable short slot time if all mesh STAs in the 86 * MBSS support ERP rates. 87 * 88 * Returns BSS_CHANGED_ERP_SLOT or 0 for no change. 89 */ 90 static u32 mesh_set_short_slot_time(struct ieee80211_sub_if_data *sdata) 91 { 92 struct ieee80211_local *local = sdata->local; 93 enum ieee80211_band band = ieee80211_get_sdata_band(sdata); 94 struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band]; 95 struct sta_info *sta; 96 u32 erp_rates = 0, changed = 0; 97 int i; 98 bool short_slot = false; 99 100 if (band == IEEE80211_BAND_5GHZ) { 101 /* (IEEE 802.11-2012 19.4.5) */ 102 short_slot = true; 103 goto out; 104 } else if (band != IEEE80211_BAND_2GHZ || 105 (band == IEEE80211_BAND_2GHZ && 106 local->hw.flags & IEEE80211_HW_2GHZ_SHORT_SLOT_INCAPABLE)) 107 goto out; 108 109 for (i = 0; i < sband->n_bitrates; i++) 110 if (sband->bitrates[i].flags & IEEE80211_RATE_ERP_G) 111 erp_rates |= BIT(i); 112 113 if (!erp_rates) 114 goto out; 115 116 rcu_read_lock(); 117 list_for_each_entry_rcu(sta, &local->sta_list, list) { 118 if (sdata != sta->sdata || 119 sta->plink_state != NL80211_PLINK_ESTAB) 120 continue; 121 122 short_slot = false; 123 if (erp_rates & sta->sta.supp_rates[band]) 124 short_slot = true; 125 else 126 break; 127 } 128 rcu_read_unlock(); 129 130 out: 131 if (sdata->vif.bss_conf.use_short_slot != short_slot) { 132 sdata->vif.bss_conf.use_short_slot = short_slot; 133 changed = BSS_CHANGED_ERP_SLOT; 134 mpl_dbg(sdata, "mesh_plink %pM: ERP short slot time %d\n", 135 sdata->vif.addr, short_slot); 136 } 137 return changed; 138 } 139 140 /** 141 * mesh_set_ht_prot_mode - set correct HT protection mode 142 * 143 * Section 9.23.3.5 of IEEE 80211-2012 describes the protection rules for HT 144 * mesh STA in a MBSS. Three HT protection modes are supported for now, non-HT 145 * mixed mode, 20MHz-protection and no-protection mode. non-HT mixed mode is 146 * selected if any non-HT peers are present in our MBSS. 20MHz-protection mode 147 * is selected if all peers in our 20/40MHz MBSS support HT and atleast one 148 * HT20 peer is present. Otherwise no-protection mode is selected. 149 */ 150 static u32 mesh_set_ht_prot_mode(struct ieee80211_sub_if_data *sdata) 151 { 152 struct ieee80211_local *local = sdata->local; 153 struct sta_info *sta; 154 u16 ht_opmode; 155 bool non_ht_sta = false, ht20_sta = false; 156 157 if (sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT) 158 return 0; 159 160 rcu_read_lock(); 161 list_for_each_entry_rcu(sta, &local->sta_list, list) { 162 if (sdata != sta->sdata || 163 sta->plink_state != NL80211_PLINK_ESTAB) 164 continue; 165 166 if (sta->sta.bandwidth > IEEE80211_STA_RX_BW_20) 167 continue; 168 169 if (!sta->sta.ht_cap.ht_supported) { 170 mpl_dbg(sdata, "nonHT sta (%pM) is present\n", 171 sta->sta.addr); 172 non_ht_sta = true; 173 break; 174 } 175 176 mpl_dbg(sdata, "HT20 sta (%pM) is present\n", sta->sta.addr); 177 ht20_sta = true; 178 } 179 rcu_read_unlock(); 180 181 if (non_ht_sta) 182 ht_opmode = IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED; 183 else if (ht20_sta && 184 sdata->vif.bss_conf.chandef.width > NL80211_CHAN_WIDTH_20) 185 ht_opmode = IEEE80211_HT_OP_MODE_PROTECTION_20MHZ; 186 else 187 ht_opmode = IEEE80211_HT_OP_MODE_PROTECTION_NONE; 188 189 if (sdata->vif.bss_conf.ht_operation_mode == ht_opmode) 190 return 0; 191 192 sdata->vif.bss_conf.ht_operation_mode = ht_opmode; 193 sdata->u.mesh.mshcfg.ht_opmode = ht_opmode; 194 mpl_dbg(sdata, "selected new HT protection mode %d\n", ht_opmode); 195 return BSS_CHANGED_HT; 196 } 197 198 /** 199 * __mesh_plink_deactivate - deactivate mesh peer link 200 * 201 * @sta: mesh peer link to deactivate 202 * 203 * All mesh paths with this peer as next hop will be flushed 204 * Returns beacon changed flag if the beacon content changed. 205 * 206 * Locking: the caller must hold sta->lock 207 */ 208 static u32 __mesh_plink_deactivate(struct sta_info *sta) 209 { 210 struct ieee80211_sub_if_data *sdata = sta->sdata; 211 u32 changed = 0; 212 213 if (sta->plink_state == NL80211_PLINK_ESTAB) 214 changed = mesh_plink_dec_estab_count(sdata); 215 sta->plink_state = NL80211_PLINK_BLOCKED; 216 mesh_path_flush_by_nexthop(sta); 217 218 ieee80211_mps_sta_status_update(sta); 219 changed |= ieee80211_mps_local_status_update(sdata); 220 221 return changed; 222 } 223 224 /** 225 * mesh_plink_deactivate - deactivate mesh peer link 226 * 227 * @sta: mesh peer link to deactivate 228 * 229 * All mesh paths with this peer as next hop will be flushed 230 */ 231 u32 mesh_plink_deactivate(struct sta_info *sta) 232 { 233 struct ieee80211_sub_if_data *sdata = sta->sdata; 234 u32 changed; 235 236 spin_lock_bh(&sta->lock); 237 changed = __mesh_plink_deactivate(sta); 238 sta->reason = cpu_to_le16(WLAN_REASON_MESH_PEER_CANCELED); 239 mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_CLOSE, 240 sta->sta.addr, sta->llid, sta->plid, 241 sta->reason); 242 spin_unlock_bh(&sta->lock); 243 244 return changed; 245 } 246 247 static int mesh_plink_frame_tx(struct ieee80211_sub_if_data *sdata, 248 enum ieee80211_self_protected_actioncode action, 249 u8 *da, __le16 llid, __le16 plid, __le16 reason) 250 { 251 struct ieee80211_local *local = sdata->local; 252 struct sk_buff *skb; 253 struct ieee80211_tx_info *info; 254 struct ieee80211_mgmt *mgmt; 255 bool include_plid = false; 256 u16 peering_proto = 0; 257 u8 *pos, ie_len = 4; 258 int hdr_len = offsetof(struct ieee80211_mgmt, u.action.u.self_prot) + 259 sizeof(mgmt->u.action.u.self_prot); 260 int err = -ENOMEM; 261 262 skb = dev_alloc_skb(local->tx_headroom + 263 hdr_len + 264 2 + /* capability info */ 265 2 + /* AID */ 266 2 + 8 + /* supported rates */ 267 2 + (IEEE80211_MAX_SUPP_RATES - 8) + 268 2 + sdata->u.mesh.mesh_id_len + 269 2 + sizeof(struct ieee80211_meshconf_ie) + 270 2 + sizeof(struct ieee80211_ht_cap) + 271 2 + sizeof(struct ieee80211_ht_operation) + 272 2 + 8 + /* peering IE */ 273 sdata->u.mesh.ie_len); 274 if (!skb) 275 return -1; 276 info = IEEE80211_SKB_CB(skb); 277 skb_reserve(skb, local->tx_headroom); 278 mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len); 279 memset(mgmt, 0, hdr_len); 280 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 281 IEEE80211_STYPE_ACTION); 282 memcpy(mgmt->da, da, ETH_ALEN); 283 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN); 284 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN); 285 mgmt->u.action.category = WLAN_CATEGORY_SELF_PROTECTED; 286 mgmt->u.action.u.self_prot.action_code = action; 287 288 if (action != WLAN_SP_MESH_PEERING_CLOSE) { 289 enum ieee80211_band band = ieee80211_get_sdata_band(sdata); 290 291 /* capability info */ 292 pos = skb_put(skb, 2); 293 memset(pos, 0, 2); 294 if (action == WLAN_SP_MESH_PEERING_CONFIRM) { 295 /* AID */ 296 pos = skb_put(skb, 2); 297 memcpy(pos + 2, &plid, 2); 298 } 299 if (ieee80211_add_srates_ie(sdata, skb, true, band) || 300 ieee80211_add_ext_srates_ie(sdata, skb, true, band) || 301 mesh_add_rsn_ie(sdata, skb) || 302 mesh_add_meshid_ie(sdata, skb) || 303 mesh_add_meshconf_ie(sdata, skb)) 304 goto free; 305 } else { /* WLAN_SP_MESH_PEERING_CLOSE */ 306 info->flags |= IEEE80211_TX_CTL_NO_ACK; 307 if (mesh_add_meshid_ie(sdata, skb)) 308 goto free; 309 } 310 311 /* Add Mesh Peering Management element */ 312 switch (action) { 313 case WLAN_SP_MESH_PEERING_OPEN: 314 break; 315 case WLAN_SP_MESH_PEERING_CONFIRM: 316 ie_len += 2; 317 include_plid = true; 318 break; 319 case WLAN_SP_MESH_PEERING_CLOSE: 320 if (plid) { 321 ie_len += 2; 322 include_plid = true; 323 } 324 ie_len += 2; /* reason code */ 325 break; 326 default: 327 err = -EINVAL; 328 goto free; 329 } 330 331 if (WARN_ON(skb_tailroom(skb) < 2 + ie_len)) 332 goto free; 333 334 pos = skb_put(skb, 2 + ie_len); 335 *pos++ = WLAN_EID_PEER_MGMT; 336 *pos++ = ie_len; 337 memcpy(pos, &peering_proto, 2); 338 pos += 2; 339 memcpy(pos, &llid, 2); 340 pos += 2; 341 if (include_plid) { 342 memcpy(pos, &plid, 2); 343 pos += 2; 344 } 345 if (action == WLAN_SP_MESH_PEERING_CLOSE) { 346 memcpy(pos, &reason, 2); 347 pos += 2; 348 } 349 350 if (action != WLAN_SP_MESH_PEERING_CLOSE) { 351 if (mesh_add_ht_cap_ie(sdata, skb) || 352 mesh_add_ht_oper_ie(sdata, skb)) 353 goto free; 354 } 355 356 if (mesh_add_vendor_ies(sdata, skb)) 357 goto free; 358 359 ieee80211_tx_skb(sdata, skb); 360 return 0; 361 free: 362 kfree_skb(skb); 363 return err; 364 } 365 366 static void mesh_sta_info_init(struct ieee80211_sub_if_data *sdata, 367 struct sta_info *sta, 368 struct ieee802_11_elems *elems, bool insert) 369 { 370 struct ieee80211_local *local = sdata->local; 371 enum ieee80211_band band = ieee80211_get_sdata_band(sdata); 372 struct ieee80211_supported_band *sband; 373 u32 rates, basic_rates = 0, changed = 0; 374 375 sband = local->hw.wiphy->bands[band]; 376 rates = ieee80211_sta_get_rates(local, elems, band, &basic_rates); 377 378 spin_lock_bh(&sta->lock); 379 sta->last_rx = jiffies; 380 381 /* rates and capabilities don't change during peering */ 382 if (sta->plink_state == NL80211_PLINK_ESTAB) 383 goto out; 384 385 if (sta->sta.supp_rates[band] != rates) 386 changed |= IEEE80211_RC_SUPP_RATES_CHANGED; 387 sta->sta.supp_rates[band] = rates; 388 389 if (ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband, 390 elems->ht_cap_elem, sta)) 391 changed |= IEEE80211_RC_BW_CHANGED; 392 393 /* HT peer is operating 20MHz-only */ 394 if (elems->ht_operation && 395 !(elems->ht_operation->ht_param & 396 IEEE80211_HT_PARAM_CHAN_WIDTH_ANY)) { 397 if (sta->sta.bandwidth != IEEE80211_STA_RX_BW_20) 398 changed |= IEEE80211_RC_BW_CHANGED; 399 sta->sta.bandwidth = IEEE80211_STA_RX_BW_20; 400 } 401 402 if (insert) 403 rate_control_rate_init(sta); 404 else 405 rate_control_rate_update(local, sband, sta, changed); 406 out: 407 spin_unlock_bh(&sta->lock); 408 } 409 410 static struct sta_info * 411 __mesh_sta_info_alloc(struct ieee80211_sub_if_data *sdata, u8 *hw_addr) 412 { 413 struct sta_info *sta; 414 415 if (sdata->local->num_sta >= MESH_MAX_PLINKS) 416 return NULL; 417 418 sta = sta_info_alloc(sdata, hw_addr, GFP_KERNEL); 419 if (!sta) 420 return NULL; 421 422 sta->plink_state = NL80211_PLINK_LISTEN; 423 424 sta_info_pre_move_state(sta, IEEE80211_STA_AUTH); 425 sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC); 426 sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED); 427 428 set_sta_flag(sta, WLAN_STA_WME); 429 430 return sta; 431 } 432 433 static struct sta_info * 434 mesh_sta_info_alloc(struct ieee80211_sub_if_data *sdata, u8 *addr, 435 struct ieee802_11_elems *elems) 436 { 437 struct sta_info *sta = NULL; 438 439 /* Userspace handles station allocation */ 440 if (sdata->u.mesh.user_mpm || 441 sdata->u.mesh.security & IEEE80211_MESH_SEC_AUTHED) 442 cfg80211_notify_new_peer_candidate(sdata->dev, addr, 443 elems->ie_start, 444 elems->total_len, 445 GFP_KERNEL); 446 else 447 sta = __mesh_sta_info_alloc(sdata, addr); 448 449 return sta; 450 } 451 452 /* 453 * mesh_sta_info_get - return mesh sta info entry for @addr. 454 * 455 * @sdata: local meshif 456 * @addr: peer's address 457 * @elems: IEs from beacon or mesh peering frame. 458 * 459 * Return existing or newly allocated sta_info under RCU read lock. 460 * (re)initialize with given IEs. 461 */ 462 static struct sta_info * 463 mesh_sta_info_get(struct ieee80211_sub_if_data *sdata, 464 u8 *addr, struct ieee802_11_elems *elems) __acquires(RCU) 465 { 466 struct sta_info *sta = NULL; 467 468 rcu_read_lock(); 469 sta = sta_info_get(sdata, addr); 470 if (sta) { 471 mesh_sta_info_init(sdata, sta, elems, false); 472 } else { 473 rcu_read_unlock(); 474 /* can't run atomic */ 475 sta = mesh_sta_info_alloc(sdata, addr, elems); 476 if (!sta) { 477 rcu_read_lock(); 478 return NULL; 479 } 480 481 mesh_sta_info_init(sdata, sta, elems, true); 482 483 if (sta_info_insert_rcu(sta)) 484 return NULL; 485 } 486 487 return sta; 488 } 489 490 /* 491 * mesh_neighbour_update - update or initialize new mesh neighbor. 492 * 493 * @sdata: local meshif 494 * @addr: peer's address 495 * @elems: IEs from beacon or mesh peering frame 496 * 497 * Initiates peering if appropriate. 498 */ 499 void mesh_neighbour_update(struct ieee80211_sub_if_data *sdata, 500 u8 *hw_addr, 501 struct ieee802_11_elems *elems) 502 { 503 struct sta_info *sta; 504 u32 changed = 0; 505 506 sta = mesh_sta_info_get(sdata, hw_addr, elems); 507 if (!sta) 508 goto out; 509 510 if (mesh_peer_accepts_plinks(elems) && 511 sta->plink_state == NL80211_PLINK_LISTEN && 512 sdata->u.mesh.accepting_plinks && 513 sdata->u.mesh.mshcfg.auto_open_plinks && 514 rssi_threshold_check(sta, sdata)) 515 changed = mesh_plink_open(sta); 516 517 ieee80211_mps_frame_release(sta, elems); 518 out: 519 rcu_read_unlock(); 520 ieee80211_mbss_info_change_notify(sdata, changed); 521 } 522 523 static void mesh_plink_timer(unsigned long data) 524 { 525 struct sta_info *sta; 526 __le16 llid, plid, reason; 527 struct ieee80211_sub_if_data *sdata; 528 struct mesh_config *mshcfg; 529 530 /* 531 * This STA is valid because sta_info_destroy() will 532 * del_timer_sync() this timer after having made sure 533 * it cannot be readded (by deleting the plink.) 534 */ 535 sta = (struct sta_info *) data; 536 537 if (sta->sdata->local->quiescing) 538 return; 539 540 spin_lock_bh(&sta->lock); 541 if (sta->ignore_plink_timer) { 542 sta->ignore_plink_timer = false; 543 spin_unlock_bh(&sta->lock); 544 return; 545 } 546 mpl_dbg(sta->sdata, 547 "Mesh plink timer for %pM fired on state %s\n", 548 sta->sta.addr, mplstates[sta->plink_state]); 549 reason = 0; 550 llid = sta->llid; 551 plid = sta->plid; 552 sdata = sta->sdata; 553 mshcfg = &sdata->u.mesh.mshcfg; 554 555 switch (sta->plink_state) { 556 case NL80211_PLINK_OPN_RCVD: 557 case NL80211_PLINK_OPN_SNT: 558 /* retry timer */ 559 if (sta->plink_retries < mshcfg->dot11MeshMaxRetries) { 560 u32 rand; 561 mpl_dbg(sta->sdata, 562 "Mesh plink for %pM (retry, timeout): %d %d\n", 563 sta->sta.addr, sta->plink_retries, 564 sta->plink_timeout); 565 get_random_bytes(&rand, sizeof(u32)); 566 sta->plink_timeout = sta->plink_timeout + 567 rand % sta->plink_timeout; 568 ++sta->plink_retries; 569 mod_plink_timer(sta, sta->plink_timeout); 570 spin_unlock_bh(&sta->lock); 571 mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_OPEN, 572 sta->sta.addr, llid, 0, 0); 573 break; 574 } 575 reason = cpu_to_le16(WLAN_REASON_MESH_MAX_RETRIES); 576 /* fall through on else */ 577 case NL80211_PLINK_CNF_RCVD: 578 /* confirm timer */ 579 if (!reason) 580 reason = cpu_to_le16(WLAN_REASON_MESH_CONFIRM_TIMEOUT); 581 sta->plink_state = NL80211_PLINK_HOLDING; 582 mod_plink_timer(sta, mshcfg->dot11MeshHoldingTimeout); 583 spin_unlock_bh(&sta->lock); 584 mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_CLOSE, 585 sta->sta.addr, llid, plid, reason); 586 break; 587 case NL80211_PLINK_HOLDING: 588 /* holding timer */ 589 del_timer(&sta->plink_timer); 590 mesh_plink_fsm_restart(sta); 591 spin_unlock_bh(&sta->lock); 592 break; 593 default: 594 spin_unlock_bh(&sta->lock); 595 break; 596 } 597 } 598 599 static inline void mesh_plink_timer_set(struct sta_info *sta, int timeout) 600 { 601 sta->plink_timer.expires = jiffies + (HZ * timeout / 1000); 602 sta->plink_timer.data = (unsigned long) sta; 603 sta->plink_timer.function = mesh_plink_timer; 604 sta->plink_timeout = timeout; 605 add_timer(&sta->plink_timer); 606 } 607 608 u32 mesh_plink_open(struct sta_info *sta) 609 { 610 __le16 llid; 611 struct ieee80211_sub_if_data *sdata = sta->sdata; 612 u32 changed; 613 614 if (!test_sta_flag(sta, WLAN_STA_AUTH)) 615 return 0; 616 617 spin_lock_bh(&sta->lock); 618 get_random_bytes(&llid, 2); 619 sta->llid = llid; 620 if (sta->plink_state != NL80211_PLINK_LISTEN && 621 sta->plink_state != NL80211_PLINK_BLOCKED) { 622 spin_unlock_bh(&sta->lock); 623 return 0; 624 } 625 sta->plink_state = NL80211_PLINK_OPN_SNT; 626 mesh_plink_timer_set(sta, sdata->u.mesh.mshcfg.dot11MeshRetryTimeout); 627 spin_unlock_bh(&sta->lock); 628 mpl_dbg(sdata, 629 "Mesh plink: starting establishment with %pM\n", 630 sta->sta.addr); 631 632 /* set the non-peer mode to active during peering */ 633 changed = ieee80211_mps_local_status_update(sdata); 634 635 mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_OPEN, 636 sta->sta.addr, llid, 0, 0); 637 return changed; 638 } 639 640 u32 mesh_plink_block(struct sta_info *sta) 641 { 642 u32 changed; 643 644 spin_lock_bh(&sta->lock); 645 changed = __mesh_plink_deactivate(sta); 646 sta->plink_state = NL80211_PLINK_BLOCKED; 647 spin_unlock_bh(&sta->lock); 648 649 return changed; 650 } 651 652 653 void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata, 654 struct ieee80211_mgmt *mgmt, size_t len, 655 struct ieee80211_rx_status *rx_status) 656 { 657 struct mesh_config *mshcfg = &sdata->u.mesh.mshcfg; 658 struct ieee802_11_elems elems; 659 struct sta_info *sta; 660 enum plink_event event; 661 enum ieee80211_self_protected_actioncode ftype; 662 size_t baselen; 663 bool matches_local = true; 664 u8 ie_len; 665 u8 *baseaddr; 666 u32 changed = 0; 667 __le16 plid, llid, reason; 668 669 /* need action_code, aux */ 670 if (len < IEEE80211_MIN_ACTION_SIZE + 3) 671 return; 672 673 if (sdata->u.mesh.user_mpm) 674 /* userspace must register for these */ 675 return; 676 677 if (is_multicast_ether_addr(mgmt->da)) { 678 mpl_dbg(sdata, 679 "Mesh plink: ignore frame from multicast address\n"); 680 return; 681 } 682 683 baseaddr = mgmt->u.action.u.self_prot.variable; 684 baselen = (u8 *) mgmt->u.action.u.self_prot.variable - (u8 *) mgmt; 685 if (mgmt->u.action.u.self_prot.action_code == 686 WLAN_SP_MESH_PEERING_CONFIRM) { 687 baseaddr += 4; 688 baselen += 4; 689 } 690 ieee802_11_parse_elems(baseaddr, len - baselen, true, &elems); 691 692 if (!elems.peering) { 693 mpl_dbg(sdata, 694 "Mesh plink: missing necessary peer link ie\n"); 695 return; 696 } 697 698 if (elems.rsn_len && 699 sdata->u.mesh.security == IEEE80211_MESH_SEC_NONE) { 700 mpl_dbg(sdata, 701 "Mesh plink: can't establish link with secure peer\n"); 702 return; 703 } 704 705 ftype = mgmt->u.action.u.self_prot.action_code; 706 ie_len = elems.peering_len; 707 if ((ftype == WLAN_SP_MESH_PEERING_OPEN && ie_len != 4) || 708 (ftype == WLAN_SP_MESH_PEERING_CONFIRM && ie_len != 6) || 709 (ftype == WLAN_SP_MESH_PEERING_CLOSE && ie_len != 6 710 && ie_len != 8)) { 711 mpl_dbg(sdata, 712 "Mesh plink: incorrect plink ie length %d %d\n", 713 ftype, ie_len); 714 return; 715 } 716 717 if (ftype != WLAN_SP_MESH_PEERING_CLOSE && 718 (!elems.mesh_id || !elems.mesh_config)) { 719 mpl_dbg(sdata, "Mesh plink: missing necessary ie\n"); 720 return; 721 } 722 /* Note the lines below are correct, the llid in the frame is the plid 723 * from the point of view of this host. 724 */ 725 memcpy(&plid, PLINK_GET_LLID(elems.peering), 2); 726 if (ftype == WLAN_SP_MESH_PEERING_CONFIRM || 727 (ftype == WLAN_SP_MESH_PEERING_CLOSE && ie_len == 8)) 728 memcpy(&llid, PLINK_GET_PLID(elems.peering), 2); 729 730 /* WARNING: Only for sta pointer, is dropped & re-acquired */ 731 rcu_read_lock(); 732 733 sta = sta_info_get(sdata, mgmt->sa); 734 if (!sta && ftype != WLAN_SP_MESH_PEERING_OPEN) { 735 mpl_dbg(sdata, "Mesh plink: cls or cnf from unknown peer\n"); 736 rcu_read_unlock(); 737 return; 738 } 739 740 if (ftype == WLAN_SP_MESH_PEERING_OPEN && 741 !rssi_threshold_check(sta, sdata)) { 742 mpl_dbg(sdata, "Mesh plink: %pM does not meet rssi threshold\n", 743 mgmt->sa); 744 rcu_read_unlock(); 745 return; 746 } 747 748 if (sta && !test_sta_flag(sta, WLAN_STA_AUTH)) { 749 mpl_dbg(sdata, "Mesh plink: Action frame from non-authed peer\n"); 750 rcu_read_unlock(); 751 return; 752 } 753 754 if (sta && sta->plink_state == NL80211_PLINK_BLOCKED) { 755 rcu_read_unlock(); 756 return; 757 } 758 759 /* Now we will figure out the appropriate event... */ 760 event = PLINK_UNDEFINED; 761 if (ftype != WLAN_SP_MESH_PEERING_CLOSE && 762 !mesh_matches_local(sdata, &elems)) { 763 matches_local = false; 764 switch (ftype) { 765 case WLAN_SP_MESH_PEERING_OPEN: 766 event = OPN_RJCT; 767 break; 768 case WLAN_SP_MESH_PEERING_CONFIRM: 769 event = CNF_RJCT; 770 break; 771 default: 772 break; 773 } 774 } 775 776 if (!sta && !matches_local) { 777 rcu_read_unlock(); 778 reason = cpu_to_le16(WLAN_REASON_MESH_CONFIG); 779 llid = 0; 780 mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_CLOSE, 781 mgmt->sa, llid, plid, reason); 782 return; 783 } else if (!sta) { 784 /* ftype == WLAN_SP_MESH_PEERING_OPEN */ 785 if (!mesh_plink_free_count(sdata)) { 786 mpl_dbg(sdata, "Mesh plink error: no more free plinks\n"); 787 rcu_read_unlock(); 788 return; 789 } 790 event = OPN_ACPT; 791 } else if (matches_local) { 792 switch (ftype) { 793 case WLAN_SP_MESH_PEERING_OPEN: 794 if (!mesh_plink_free_count(sdata) || 795 (sta->plid && sta->plid != plid)) 796 event = OPN_IGNR; 797 else 798 event = OPN_ACPT; 799 break; 800 case WLAN_SP_MESH_PEERING_CONFIRM: 801 if (!mesh_plink_free_count(sdata) || 802 (sta->llid != llid || sta->plid != plid)) 803 event = CNF_IGNR; 804 else 805 event = CNF_ACPT; 806 break; 807 case WLAN_SP_MESH_PEERING_CLOSE: 808 if (sta->plink_state == NL80211_PLINK_ESTAB) 809 /* Do not check for llid or plid. This does not 810 * follow the standard but since multiple plinks 811 * per sta are not supported, it is necessary in 812 * order to avoid a livelock when MP A sees an 813 * establish peer link to MP B but MP B does not 814 * see it. This can be caused by a timeout in 815 * B's peer link establishment or B beign 816 * restarted. 817 */ 818 event = CLS_ACPT; 819 else if (sta->plid != plid) 820 event = CLS_IGNR; 821 else if (ie_len == 7 && sta->llid != llid) 822 event = CLS_IGNR; 823 else 824 event = CLS_ACPT; 825 break; 826 default: 827 mpl_dbg(sdata, "Mesh plink: unknown frame subtype\n"); 828 rcu_read_unlock(); 829 return; 830 } 831 } 832 833 if (event == OPN_ACPT) { 834 rcu_read_unlock(); 835 /* allocate sta entry if necessary and update info */ 836 sta = mesh_sta_info_get(sdata, mgmt->sa, &elems); 837 if (!sta) { 838 mpl_dbg(sdata, "Mesh plink: failed to init peer!\n"); 839 rcu_read_unlock(); 840 return; 841 } 842 } 843 844 mpl_dbg(sdata, "peer %pM in state %s got event %s\n", mgmt->sa, 845 mplstates[sta->plink_state], mplevents[event]); 846 reason = 0; 847 spin_lock_bh(&sta->lock); 848 switch (sta->plink_state) { 849 /* spin_unlock as soon as state is updated at each case */ 850 case NL80211_PLINK_LISTEN: 851 switch (event) { 852 case CLS_ACPT: 853 mesh_plink_fsm_restart(sta); 854 spin_unlock_bh(&sta->lock); 855 break; 856 case OPN_ACPT: 857 sta->plink_state = NL80211_PLINK_OPN_RCVD; 858 sta->plid = plid; 859 get_random_bytes(&llid, 2); 860 sta->llid = llid; 861 mesh_plink_timer_set(sta, 862 mshcfg->dot11MeshRetryTimeout); 863 864 /* set the non-peer mode to active during peering */ 865 changed |= ieee80211_mps_local_status_update(sdata); 866 867 spin_unlock_bh(&sta->lock); 868 mesh_plink_frame_tx(sdata, 869 WLAN_SP_MESH_PEERING_OPEN, 870 sta->sta.addr, llid, 0, 0); 871 mesh_plink_frame_tx(sdata, 872 WLAN_SP_MESH_PEERING_CONFIRM, 873 sta->sta.addr, llid, plid, 0); 874 break; 875 default: 876 spin_unlock_bh(&sta->lock); 877 break; 878 } 879 break; 880 881 case NL80211_PLINK_OPN_SNT: 882 switch (event) { 883 case OPN_RJCT: 884 case CNF_RJCT: 885 reason = cpu_to_le16(WLAN_REASON_MESH_CONFIG); 886 case CLS_ACPT: 887 if (!reason) 888 reason = cpu_to_le16(WLAN_REASON_MESH_CLOSE); 889 sta->reason = reason; 890 sta->plink_state = NL80211_PLINK_HOLDING; 891 if (!mod_plink_timer(sta, 892 mshcfg->dot11MeshHoldingTimeout)) 893 sta->ignore_plink_timer = true; 894 895 llid = sta->llid; 896 spin_unlock_bh(&sta->lock); 897 mesh_plink_frame_tx(sdata, 898 WLAN_SP_MESH_PEERING_CLOSE, 899 sta->sta.addr, llid, plid, reason); 900 break; 901 case OPN_ACPT: 902 /* retry timer is left untouched */ 903 sta->plink_state = NL80211_PLINK_OPN_RCVD; 904 sta->plid = plid; 905 llid = sta->llid; 906 spin_unlock_bh(&sta->lock); 907 mesh_plink_frame_tx(sdata, 908 WLAN_SP_MESH_PEERING_CONFIRM, 909 sta->sta.addr, llid, plid, 0); 910 break; 911 case CNF_ACPT: 912 sta->plink_state = NL80211_PLINK_CNF_RCVD; 913 if (!mod_plink_timer(sta, 914 mshcfg->dot11MeshConfirmTimeout)) 915 sta->ignore_plink_timer = true; 916 917 spin_unlock_bh(&sta->lock); 918 break; 919 default: 920 spin_unlock_bh(&sta->lock); 921 break; 922 } 923 break; 924 925 case NL80211_PLINK_OPN_RCVD: 926 switch (event) { 927 case OPN_RJCT: 928 case CNF_RJCT: 929 reason = cpu_to_le16(WLAN_REASON_MESH_CONFIG); 930 case CLS_ACPT: 931 if (!reason) 932 reason = cpu_to_le16(WLAN_REASON_MESH_CLOSE); 933 sta->reason = reason; 934 sta->plink_state = NL80211_PLINK_HOLDING; 935 if (!mod_plink_timer(sta, 936 mshcfg->dot11MeshHoldingTimeout)) 937 sta->ignore_plink_timer = true; 938 939 llid = sta->llid; 940 spin_unlock_bh(&sta->lock); 941 mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_CLOSE, 942 sta->sta.addr, llid, plid, reason); 943 break; 944 case OPN_ACPT: 945 llid = sta->llid; 946 spin_unlock_bh(&sta->lock); 947 mesh_plink_frame_tx(sdata, 948 WLAN_SP_MESH_PEERING_CONFIRM, 949 sta->sta.addr, llid, plid, 0); 950 break; 951 case CNF_ACPT: 952 del_timer(&sta->plink_timer); 953 sta->plink_state = NL80211_PLINK_ESTAB; 954 spin_unlock_bh(&sta->lock); 955 changed |= mesh_plink_inc_estab_count(sdata); 956 changed |= mesh_set_ht_prot_mode(sdata); 957 changed |= mesh_set_short_slot_time(sdata); 958 mpl_dbg(sdata, "Mesh plink with %pM ESTABLISHED\n", 959 sta->sta.addr); 960 ieee80211_mps_sta_status_update(sta); 961 changed |= ieee80211_mps_set_sta_local_pm(sta, 962 mshcfg->power_mode); 963 break; 964 default: 965 spin_unlock_bh(&sta->lock); 966 break; 967 } 968 break; 969 970 case NL80211_PLINK_CNF_RCVD: 971 switch (event) { 972 case OPN_RJCT: 973 case CNF_RJCT: 974 reason = cpu_to_le16(WLAN_REASON_MESH_CONFIG); 975 case CLS_ACPT: 976 if (!reason) 977 reason = cpu_to_le16(WLAN_REASON_MESH_CLOSE); 978 sta->reason = reason; 979 sta->plink_state = NL80211_PLINK_HOLDING; 980 if (!mod_plink_timer(sta, 981 mshcfg->dot11MeshHoldingTimeout)) 982 sta->ignore_plink_timer = true; 983 984 llid = sta->llid; 985 spin_unlock_bh(&sta->lock); 986 mesh_plink_frame_tx(sdata, 987 WLAN_SP_MESH_PEERING_CLOSE, 988 sta->sta.addr, llid, plid, reason); 989 break; 990 case OPN_ACPT: 991 del_timer(&sta->plink_timer); 992 sta->plink_state = NL80211_PLINK_ESTAB; 993 spin_unlock_bh(&sta->lock); 994 changed |= mesh_plink_inc_estab_count(sdata); 995 changed |= mesh_set_ht_prot_mode(sdata); 996 changed |= mesh_set_short_slot_time(sdata); 997 mpl_dbg(sdata, "Mesh plink with %pM ESTABLISHED\n", 998 sta->sta.addr); 999 mesh_plink_frame_tx(sdata, 1000 WLAN_SP_MESH_PEERING_CONFIRM, 1001 sta->sta.addr, llid, plid, 0); 1002 ieee80211_mps_sta_status_update(sta); 1003 changed |= ieee80211_mps_set_sta_local_pm(sta, 1004 mshcfg->power_mode); 1005 break; 1006 default: 1007 spin_unlock_bh(&sta->lock); 1008 break; 1009 } 1010 break; 1011 1012 case NL80211_PLINK_ESTAB: 1013 switch (event) { 1014 case CLS_ACPT: 1015 reason = cpu_to_le16(WLAN_REASON_MESH_CLOSE); 1016 sta->reason = reason; 1017 changed |= __mesh_plink_deactivate(sta); 1018 sta->plink_state = NL80211_PLINK_HOLDING; 1019 llid = sta->llid; 1020 mod_plink_timer(sta, mshcfg->dot11MeshHoldingTimeout); 1021 spin_unlock_bh(&sta->lock); 1022 changed |= mesh_set_ht_prot_mode(sdata); 1023 changed |= mesh_set_short_slot_time(sdata); 1024 mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_CLOSE, 1025 sta->sta.addr, llid, plid, reason); 1026 break; 1027 case OPN_ACPT: 1028 llid = sta->llid; 1029 spin_unlock_bh(&sta->lock); 1030 mesh_plink_frame_tx(sdata, 1031 WLAN_SP_MESH_PEERING_CONFIRM, 1032 sta->sta.addr, llid, plid, 0); 1033 break; 1034 default: 1035 spin_unlock_bh(&sta->lock); 1036 break; 1037 } 1038 break; 1039 case NL80211_PLINK_HOLDING: 1040 switch (event) { 1041 case CLS_ACPT: 1042 if (del_timer(&sta->plink_timer)) 1043 sta->ignore_plink_timer = 1; 1044 mesh_plink_fsm_restart(sta); 1045 spin_unlock_bh(&sta->lock); 1046 break; 1047 case OPN_ACPT: 1048 case CNF_ACPT: 1049 case OPN_RJCT: 1050 case CNF_RJCT: 1051 llid = sta->llid; 1052 reason = sta->reason; 1053 spin_unlock_bh(&sta->lock); 1054 mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_CLOSE, 1055 sta->sta.addr, llid, plid, reason); 1056 break; 1057 default: 1058 spin_unlock_bh(&sta->lock); 1059 } 1060 break; 1061 default: 1062 /* should not get here, PLINK_BLOCKED is dealt with at the 1063 * beginning of the function 1064 */ 1065 spin_unlock_bh(&sta->lock); 1066 break; 1067 } 1068 1069 rcu_read_unlock(); 1070 1071 if (changed) 1072 ieee80211_mbss_info_change_notify(sdata, changed); 1073 } 1074