mesh_plink.c revision 0f5ffd24fb732fb4d653a8ee97faea767a0e7172
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 28enum 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 40static 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 50static 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 62static 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 */ 73static 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 */ 90static 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 130out: 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 */ 150static 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 switch (sdata->vif.bss_conf.chandef.width) { 158 case NL80211_CHAN_WIDTH_20_NOHT: 159 case NL80211_CHAN_WIDTH_5: 160 case NL80211_CHAN_WIDTH_10: 161 return 0; 162 default: 163 break; 164 } 165 166 rcu_read_lock(); 167 list_for_each_entry_rcu(sta, &local->sta_list, list) { 168 if (sdata != sta->sdata || 169 sta->plink_state != NL80211_PLINK_ESTAB) 170 continue; 171 172 if (sta->sta.bandwidth > IEEE80211_STA_RX_BW_20) 173 continue; 174 175 if (!sta->sta.ht_cap.ht_supported) { 176 mpl_dbg(sdata, "nonHT sta (%pM) is present\n", 177 sta->sta.addr); 178 non_ht_sta = true; 179 break; 180 } 181 182 mpl_dbg(sdata, "HT20 sta (%pM) is present\n", sta->sta.addr); 183 ht20_sta = true; 184 } 185 rcu_read_unlock(); 186 187 if (non_ht_sta) 188 ht_opmode = IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED; 189 else if (ht20_sta && 190 sdata->vif.bss_conf.chandef.width > NL80211_CHAN_WIDTH_20) 191 ht_opmode = IEEE80211_HT_OP_MODE_PROTECTION_20MHZ; 192 else 193 ht_opmode = IEEE80211_HT_OP_MODE_PROTECTION_NONE; 194 195 if (sdata->vif.bss_conf.ht_operation_mode == ht_opmode) 196 return 0; 197 198 sdata->vif.bss_conf.ht_operation_mode = ht_opmode; 199 sdata->u.mesh.mshcfg.ht_opmode = ht_opmode; 200 mpl_dbg(sdata, "selected new HT protection mode %d\n", ht_opmode); 201 return BSS_CHANGED_HT; 202} 203 204/** 205 * __mesh_plink_deactivate - deactivate mesh peer link 206 * 207 * @sta: mesh peer link to deactivate 208 * 209 * All mesh paths with this peer as next hop will be flushed 210 * Returns beacon changed flag if the beacon content changed. 211 * 212 * Locking: the caller must hold sta->lock 213 */ 214static u32 __mesh_plink_deactivate(struct sta_info *sta) 215{ 216 struct ieee80211_sub_if_data *sdata = sta->sdata; 217 u32 changed = 0; 218 219 if (sta->plink_state == NL80211_PLINK_ESTAB) 220 changed = mesh_plink_dec_estab_count(sdata); 221 sta->plink_state = NL80211_PLINK_BLOCKED; 222 mesh_path_flush_by_nexthop(sta); 223 224 ieee80211_mps_sta_status_update(sta); 225 changed |= ieee80211_mps_set_sta_local_pm(sta, 226 NL80211_MESH_POWER_UNKNOWN); 227 228 return changed; 229} 230 231/** 232 * mesh_plink_deactivate - deactivate mesh peer link 233 * 234 * @sta: mesh peer link to deactivate 235 * 236 * All mesh paths with this peer as next hop will be flushed 237 */ 238u32 mesh_plink_deactivate(struct sta_info *sta) 239{ 240 struct ieee80211_sub_if_data *sdata = sta->sdata; 241 u32 changed; 242 243 spin_lock_bh(&sta->lock); 244 changed = __mesh_plink_deactivate(sta); 245 sta->reason = cpu_to_le16(WLAN_REASON_MESH_PEER_CANCELED); 246 mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_CLOSE, 247 sta->sta.addr, sta->llid, sta->plid, 248 sta->reason); 249 spin_unlock_bh(&sta->lock); 250 251 return changed; 252} 253 254static int mesh_plink_frame_tx(struct ieee80211_sub_if_data *sdata, 255 enum ieee80211_self_protected_actioncode action, 256 u8 *da, __le16 llid, __le16 plid, __le16 reason) 257{ 258 struct ieee80211_local *local = sdata->local; 259 struct sk_buff *skb; 260 struct ieee80211_tx_info *info; 261 struct ieee80211_mgmt *mgmt; 262 bool include_plid = false; 263 u16 peering_proto = 0; 264 u8 *pos, ie_len = 4; 265 int hdr_len = offsetof(struct ieee80211_mgmt, u.action.u.self_prot) + 266 sizeof(mgmt->u.action.u.self_prot); 267 int err = -ENOMEM; 268 269 skb = dev_alloc_skb(local->tx_headroom + 270 hdr_len + 271 2 + /* capability info */ 272 2 + /* AID */ 273 2 + 8 + /* supported rates */ 274 2 + (IEEE80211_MAX_SUPP_RATES - 8) + 275 2 + sdata->u.mesh.mesh_id_len + 276 2 + sizeof(struct ieee80211_meshconf_ie) + 277 2 + sizeof(struct ieee80211_ht_cap) + 278 2 + sizeof(struct ieee80211_ht_operation) + 279 2 + 8 + /* peering IE */ 280 sdata->u.mesh.ie_len); 281 if (!skb) 282 return -1; 283 info = IEEE80211_SKB_CB(skb); 284 skb_reserve(skb, local->tx_headroom); 285 mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len); 286 memset(mgmt, 0, hdr_len); 287 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 288 IEEE80211_STYPE_ACTION); 289 memcpy(mgmt->da, da, ETH_ALEN); 290 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN); 291 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN); 292 mgmt->u.action.category = WLAN_CATEGORY_SELF_PROTECTED; 293 mgmt->u.action.u.self_prot.action_code = action; 294 295 if (action != WLAN_SP_MESH_PEERING_CLOSE) { 296 enum ieee80211_band band = ieee80211_get_sdata_band(sdata); 297 298 /* capability info */ 299 pos = skb_put(skb, 2); 300 memset(pos, 0, 2); 301 if (action == WLAN_SP_MESH_PEERING_CONFIRM) { 302 /* AID */ 303 pos = skb_put(skb, 2); 304 memcpy(pos + 2, &plid, 2); 305 } 306 if (ieee80211_add_srates_ie(sdata, skb, true, band) || 307 ieee80211_add_ext_srates_ie(sdata, skb, true, band) || 308 mesh_add_rsn_ie(sdata, skb) || 309 mesh_add_meshid_ie(sdata, skb) || 310 mesh_add_meshconf_ie(sdata, skb)) 311 goto free; 312 } else { /* WLAN_SP_MESH_PEERING_CLOSE */ 313 info->flags |= IEEE80211_TX_CTL_NO_ACK; 314 if (mesh_add_meshid_ie(sdata, skb)) 315 goto free; 316 } 317 318 /* Add Mesh Peering Management element */ 319 switch (action) { 320 case WLAN_SP_MESH_PEERING_OPEN: 321 break; 322 case WLAN_SP_MESH_PEERING_CONFIRM: 323 ie_len += 2; 324 include_plid = true; 325 break; 326 case WLAN_SP_MESH_PEERING_CLOSE: 327 if (plid) { 328 ie_len += 2; 329 include_plid = true; 330 } 331 ie_len += 2; /* reason code */ 332 break; 333 default: 334 err = -EINVAL; 335 goto free; 336 } 337 338 if (WARN_ON(skb_tailroom(skb) < 2 + ie_len)) 339 goto free; 340 341 pos = skb_put(skb, 2 + ie_len); 342 *pos++ = WLAN_EID_PEER_MGMT; 343 *pos++ = ie_len; 344 memcpy(pos, &peering_proto, 2); 345 pos += 2; 346 memcpy(pos, &llid, 2); 347 pos += 2; 348 if (include_plid) { 349 memcpy(pos, &plid, 2); 350 pos += 2; 351 } 352 if (action == WLAN_SP_MESH_PEERING_CLOSE) { 353 memcpy(pos, &reason, 2); 354 pos += 2; 355 } 356 357 if (action != WLAN_SP_MESH_PEERING_CLOSE) { 358 if (mesh_add_ht_cap_ie(sdata, skb) || 359 mesh_add_ht_oper_ie(sdata, skb)) 360 goto free; 361 } 362 363 if (mesh_add_vendor_ies(sdata, skb)) 364 goto free; 365 366 ieee80211_tx_skb(sdata, skb); 367 return 0; 368free: 369 kfree_skb(skb); 370 return err; 371} 372 373static void mesh_sta_info_init(struct ieee80211_sub_if_data *sdata, 374 struct sta_info *sta, 375 struct ieee802_11_elems *elems, bool insert) 376{ 377 struct ieee80211_local *local = sdata->local; 378 enum ieee80211_band band = ieee80211_get_sdata_band(sdata); 379 struct ieee80211_supported_band *sband; 380 u32 rates, basic_rates = 0, changed = 0; 381 382 sband = local->hw.wiphy->bands[band]; 383 rates = ieee80211_sta_get_rates(sdata, elems, band, &basic_rates); 384 385 spin_lock_bh(&sta->lock); 386 sta->last_rx = jiffies; 387 388 /* rates and capabilities don't change during peering */ 389 if (sta->plink_state == NL80211_PLINK_ESTAB) 390 goto out; 391 392 if (sta->sta.supp_rates[band] != rates) 393 changed |= IEEE80211_RC_SUPP_RATES_CHANGED; 394 sta->sta.supp_rates[band] = rates; 395 396 if (ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband, 397 elems->ht_cap_elem, sta)) 398 changed |= IEEE80211_RC_BW_CHANGED; 399 400 /* HT peer is operating 20MHz-only */ 401 if (elems->ht_operation && 402 !(elems->ht_operation->ht_param & 403 IEEE80211_HT_PARAM_CHAN_WIDTH_ANY)) { 404 if (sta->sta.bandwidth != IEEE80211_STA_RX_BW_20) 405 changed |= IEEE80211_RC_BW_CHANGED; 406 sta->sta.bandwidth = IEEE80211_STA_RX_BW_20; 407 } 408 409 if (insert) 410 rate_control_rate_init(sta); 411 else 412 rate_control_rate_update(local, sband, sta, changed); 413out: 414 spin_unlock_bh(&sta->lock); 415} 416 417static struct sta_info * 418__mesh_sta_info_alloc(struct ieee80211_sub_if_data *sdata, u8 *hw_addr) 419{ 420 struct sta_info *sta; 421 422 if (sdata->local->num_sta >= MESH_MAX_PLINKS) 423 return NULL; 424 425 sta = sta_info_alloc(sdata, hw_addr, GFP_KERNEL); 426 if (!sta) 427 return NULL; 428 429 sta->plink_state = NL80211_PLINK_LISTEN; 430 431 sta_info_pre_move_state(sta, IEEE80211_STA_AUTH); 432 sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC); 433 sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED); 434 435 set_sta_flag(sta, WLAN_STA_WME); 436 437 return sta; 438} 439 440static struct sta_info * 441mesh_sta_info_alloc(struct ieee80211_sub_if_data *sdata, u8 *addr, 442 struct ieee802_11_elems *elems) 443{ 444 struct sta_info *sta = NULL; 445 446 /* Userspace handles station allocation */ 447 if (sdata->u.mesh.user_mpm || 448 sdata->u.mesh.security & IEEE80211_MESH_SEC_AUTHED) 449 cfg80211_notify_new_peer_candidate(sdata->dev, addr, 450 elems->ie_start, 451 elems->total_len, 452 GFP_KERNEL); 453 else 454 sta = __mesh_sta_info_alloc(sdata, addr); 455 456 return sta; 457} 458 459/* 460 * mesh_sta_info_get - return mesh sta info entry for @addr. 461 * 462 * @sdata: local meshif 463 * @addr: peer's address 464 * @elems: IEs from beacon or mesh peering frame. 465 * 466 * Return existing or newly allocated sta_info under RCU read lock. 467 * (re)initialize with given IEs. 468 */ 469static struct sta_info * 470mesh_sta_info_get(struct ieee80211_sub_if_data *sdata, 471 u8 *addr, struct ieee802_11_elems *elems) __acquires(RCU) 472{ 473 struct sta_info *sta = NULL; 474 475 rcu_read_lock(); 476 sta = sta_info_get(sdata, addr); 477 if (sta) { 478 mesh_sta_info_init(sdata, sta, elems, false); 479 } else { 480 rcu_read_unlock(); 481 /* can't run atomic */ 482 sta = mesh_sta_info_alloc(sdata, addr, elems); 483 if (!sta) { 484 rcu_read_lock(); 485 return NULL; 486 } 487 488 mesh_sta_info_init(sdata, sta, elems, true); 489 490 if (sta_info_insert_rcu(sta)) 491 return NULL; 492 } 493 494 return sta; 495} 496 497/* 498 * mesh_neighbour_update - update or initialize new mesh neighbor. 499 * 500 * @sdata: local meshif 501 * @addr: peer's address 502 * @elems: IEs from beacon or mesh peering frame 503 * 504 * Initiates peering if appropriate. 505 */ 506void mesh_neighbour_update(struct ieee80211_sub_if_data *sdata, 507 u8 *hw_addr, 508 struct ieee802_11_elems *elems) 509{ 510 struct sta_info *sta; 511 u32 changed = 0; 512 513 sta = mesh_sta_info_get(sdata, hw_addr, elems); 514 if (!sta) 515 goto out; 516 517 if (mesh_peer_accepts_plinks(elems) && 518 sta->plink_state == NL80211_PLINK_LISTEN && 519 sdata->u.mesh.accepting_plinks && 520 sdata->u.mesh.mshcfg.auto_open_plinks && 521 rssi_threshold_check(sta, sdata)) 522 changed = mesh_plink_open(sta); 523 524 ieee80211_mps_frame_release(sta, elems); 525out: 526 rcu_read_unlock(); 527 ieee80211_mbss_info_change_notify(sdata, changed); 528} 529 530static void mesh_plink_timer(unsigned long data) 531{ 532 struct sta_info *sta; 533 __le16 llid, plid, reason; 534 struct ieee80211_sub_if_data *sdata; 535 struct mesh_config *mshcfg; 536 enum ieee80211_self_protected_actioncode action = 0; 537 538 /* 539 * This STA is valid because sta_info_destroy() will 540 * del_timer_sync() this timer after having made sure 541 * it cannot be readded (by deleting the plink.) 542 */ 543 sta = (struct sta_info *) data; 544 545 if (sta->sdata->local->quiescing) 546 return; 547 548 spin_lock_bh(&sta->lock); 549 if (sta->ignore_plink_timer) { 550 sta->ignore_plink_timer = false; 551 spin_unlock_bh(&sta->lock); 552 return; 553 } 554 mpl_dbg(sta->sdata, 555 "Mesh plink timer for %pM fired on state %s\n", 556 sta->sta.addr, mplstates[sta->plink_state]); 557 reason = 0; 558 llid = sta->llid; 559 plid = sta->plid; 560 sdata = sta->sdata; 561 mshcfg = &sdata->u.mesh.mshcfg; 562 563 switch (sta->plink_state) { 564 case NL80211_PLINK_OPN_RCVD: 565 case NL80211_PLINK_OPN_SNT: 566 /* retry timer */ 567 if (sta->plink_retries < mshcfg->dot11MeshMaxRetries) { 568 u32 rand; 569 mpl_dbg(sta->sdata, 570 "Mesh plink for %pM (retry, timeout): %d %d\n", 571 sta->sta.addr, sta->plink_retries, 572 sta->plink_timeout); 573 get_random_bytes(&rand, sizeof(u32)); 574 sta->plink_timeout = sta->plink_timeout + 575 rand % sta->plink_timeout; 576 ++sta->plink_retries; 577 mod_plink_timer(sta, sta->plink_timeout); 578 action = WLAN_SP_MESH_PEERING_OPEN; 579 break; 580 } 581 reason = cpu_to_le16(WLAN_REASON_MESH_MAX_RETRIES); 582 /* fall through on else */ 583 case NL80211_PLINK_CNF_RCVD: 584 /* confirm timer */ 585 if (!reason) 586 reason = cpu_to_le16(WLAN_REASON_MESH_CONFIRM_TIMEOUT); 587 sta->plink_state = NL80211_PLINK_HOLDING; 588 mod_plink_timer(sta, mshcfg->dot11MeshHoldingTimeout); 589 action = WLAN_SP_MESH_PEERING_CLOSE; 590 break; 591 case NL80211_PLINK_HOLDING: 592 /* holding timer */ 593 del_timer(&sta->plink_timer); 594 mesh_plink_fsm_restart(sta); 595 break; 596 default: 597 break; 598 } 599 spin_unlock_bh(&sta->lock); 600 if (action) 601 mesh_plink_frame_tx(sdata, action, sta->sta.addr, 602 llid, plid, reason); 603} 604 605static inline void mesh_plink_timer_set(struct sta_info *sta, int timeout) 606{ 607 sta->plink_timer.expires = jiffies + (HZ * timeout / 1000); 608 sta->plink_timer.data = (unsigned long) sta; 609 sta->plink_timer.function = mesh_plink_timer; 610 sta->plink_timeout = timeout; 611 add_timer(&sta->plink_timer); 612} 613 614u32 mesh_plink_open(struct sta_info *sta) 615{ 616 __le16 llid; 617 struct ieee80211_sub_if_data *sdata = sta->sdata; 618 u32 changed; 619 620 if (!test_sta_flag(sta, WLAN_STA_AUTH)) 621 return 0; 622 623 spin_lock_bh(&sta->lock); 624 get_random_bytes(&llid, 2); 625 sta->llid = llid; 626 if (sta->plink_state != NL80211_PLINK_LISTEN && 627 sta->plink_state != NL80211_PLINK_BLOCKED) { 628 spin_unlock_bh(&sta->lock); 629 return 0; 630 } 631 sta->plink_state = NL80211_PLINK_OPN_SNT; 632 mesh_plink_timer_set(sta, sdata->u.mesh.mshcfg.dot11MeshRetryTimeout); 633 spin_unlock_bh(&sta->lock); 634 mpl_dbg(sdata, 635 "Mesh plink: starting establishment with %pM\n", 636 sta->sta.addr); 637 638 /* set the non-peer mode to active during peering */ 639 changed = ieee80211_mps_local_status_update(sdata); 640 641 mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_OPEN, 642 sta->sta.addr, llid, 0, 0); 643 return changed; 644} 645 646u32 mesh_plink_block(struct sta_info *sta) 647{ 648 u32 changed; 649 650 spin_lock_bh(&sta->lock); 651 changed = __mesh_plink_deactivate(sta); 652 sta->plink_state = NL80211_PLINK_BLOCKED; 653 spin_unlock_bh(&sta->lock); 654 655 return changed; 656} 657 658 659void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata, 660 struct ieee80211_mgmt *mgmt, size_t len, 661 struct ieee80211_rx_status *rx_status) 662{ 663 struct mesh_config *mshcfg = &sdata->u.mesh.mshcfg; 664 enum ieee80211_self_protected_actioncode action = 0; 665 struct ieee802_11_elems elems; 666 struct sta_info *sta; 667 enum plink_event event; 668 enum ieee80211_self_protected_actioncode ftype; 669 size_t baselen; 670 bool matches_local = true; 671 u8 ie_len; 672 u8 *baseaddr; 673 u32 changed = 0; 674 __le16 plid, llid, reason; 675 676 /* need action_code, aux */ 677 if (len < IEEE80211_MIN_ACTION_SIZE + 3) 678 return; 679 680 if (sdata->u.mesh.user_mpm) 681 /* userspace must register for these */ 682 return; 683 684 if (is_multicast_ether_addr(mgmt->da)) { 685 mpl_dbg(sdata, 686 "Mesh plink: ignore frame from multicast address\n"); 687 return; 688 } 689 690 baseaddr = mgmt->u.action.u.self_prot.variable; 691 baselen = (u8 *) mgmt->u.action.u.self_prot.variable - (u8 *) mgmt; 692 if (mgmt->u.action.u.self_prot.action_code == 693 WLAN_SP_MESH_PEERING_CONFIRM) { 694 baseaddr += 4; 695 baselen += 4; 696 } 697 ieee802_11_parse_elems(baseaddr, len - baselen, true, &elems); 698 699 if (!elems.peering) { 700 mpl_dbg(sdata, 701 "Mesh plink: missing necessary peer link ie\n"); 702 return; 703 } 704 705 if (elems.rsn_len && 706 sdata->u.mesh.security == IEEE80211_MESH_SEC_NONE) { 707 mpl_dbg(sdata, 708 "Mesh plink: can't establish link with secure peer\n"); 709 return; 710 } 711 712 ftype = mgmt->u.action.u.self_prot.action_code; 713 ie_len = elems.peering_len; 714 if ((ftype == WLAN_SP_MESH_PEERING_OPEN && ie_len != 4) || 715 (ftype == WLAN_SP_MESH_PEERING_CONFIRM && ie_len != 6) || 716 (ftype == WLAN_SP_MESH_PEERING_CLOSE && ie_len != 6 717 && ie_len != 8)) { 718 mpl_dbg(sdata, 719 "Mesh plink: incorrect plink ie length %d %d\n", 720 ftype, ie_len); 721 return; 722 } 723 724 if (ftype != WLAN_SP_MESH_PEERING_CLOSE && 725 (!elems.mesh_id || !elems.mesh_config)) { 726 mpl_dbg(sdata, "Mesh plink: missing necessary ie\n"); 727 return; 728 } 729 /* Note the lines below are correct, the llid in the frame is the plid 730 * from the point of view of this host. 731 */ 732 memcpy(&plid, PLINK_GET_LLID(elems.peering), 2); 733 if (ftype == WLAN_SP_MESH_PEERING_CONFIRM || 734 (ftype == WLAN_SP_MESH_PEERING_CLOSE && ie_len == 8)) 735 memcpy(&llid, PLINK_GET_PLID(elems.peering), 2); 736 737 /* WARNING: Only for sta pointer, is dropped & re-acquired */ 738 rcu_read_lock(); 739 740 sta = sta_info_get(sdata, mgmt->sa); 741 if (!sta && ftype != WLAN_SP_MESH_PEERING_OPEN) { 742 mpl_dbg(sdata, "Mesh plink: cls or cnf from unknown peer\n"); 743 rcu_read_unlock(); 744 return; 745 } 746 747 if (ftype == WLAN_SP_MESH_PEERING_OPEN && 748 !rssi_threshold_check(sta, sdata)) { 749 mpl_dbg(sdata, "Mesh plink: %pM does not meet rssi threshold\n", 750 mgmt->sa); 751 rcu_read_unlock(); 752 return; 753 } 754 755 if (sta && !test_sta_flag(sta, WLAN_STA_AUTH)) { 756 mpl_dbg(sdata, "Mesh plink: Action frame from non-authed peer\n"); 757 rcu_read_unlock(); 758 return; 759 } 760 761 if (sta && sta->plink_state == NL80211_PLINK_BLOCKED) { 762 rcu_read_unlock(); 763 return; 764 } 765 766 /* Now we will figure out the appropriate event... */ 767 event = PLINK_UNDEFINED; 768 if (ftype != WLAN_SP_MESH_PEERING_CLOSE && 769 !mesh_matches_local(sdata, &elems)) { 770 matches_local = false; 771 switch (ftype) { 772 case WLAN_SP_MESH_PEERING_OPEN: 773 event = OPN_RJCT; 774 break; 775 case WLAN_SP_MESH_PEERING_CONFIRM: 776 event = CNF_RJCT; 777 break; 778 default: 779 break; 780 } 781 } 782 783 if (!sta && !matches_local) { 784 rcu_read_unlock(); 785 reason = cpu_to_le16(WLAN_REASON_MESH_CONFIG); 786 llid = 0; 787 mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_CLOSE, 788 mgmt->sa, llid, plid, reason); 789 return; 790 } else if (!sta) { 791 /* ftype == WLAN_SP_MESH_PEERING_OPEN */ 792 if (!mesh_plink_free_count(sdata)) { 793 mpl_dbg(sdata, "Mesh plink error: no more free plinks\n"); 794 rcu_read_unlock(); 795 return; 796 } 797 event = OPN_ACPT; 798 } else if (matches_local) { 799 switch (ftype) { 800 case WLAN_SP_MESH_PEERING_OPEN: 801 if (!mesh_plink_free_count(sdata) || 802 (sta->plid && sta->plid != plid)) 803 event = OPN_IGNR; 804 else 805 event = OPN_ACPT; 806 break; 807 case WLAN_SP_MESH_PEERING_CONFIRM: 808 if (!mesh_plink_free_count(sdata) || 809 (sta->llid != llid || sta->plid != plid)) 810 event = CNF_IGNR; 811 else 812 event = CNF_ACPT; 813 break; 814 case WLAN_SP_MESH_PEERING_CLOSE: 815 if (sta->plink_state == NL80211_PLINK_ESTAB) 816 /* Do not check for llid or plid. This does not 817 * follow the standard but since multiple plinks 818 * per sta are not supported, it is necessary in 819 * order to avoid a livelock when MP A sees an 820 * establish peer link to MP B but MP B does not 821 * see it. This can be caused by a timeout in 822 * B's peer link establishment or B beign 823 * restarted. 824 */ 825 event = CLS_ACPT; 826 else if (sta->plid != plid) 827 event = CLS_IGNR; 828 else if (ie_len == 8 && sta->llid != llid) 829 event = CLS_IGNR; 830 else 831 event = CLS_ACPT; 832 break; 833 default: 834 mpl_dbg(sdata, "Mesh plink: unknown frame subtype\n"); 835 rcu_read_unlock(); 836 return; 837 } 838 } 839 840 if (event == OPN_ACPT) { 841 rcu_read_unlock(); 842 /* allocate sta entry if necessary and update info */ 843 sta = mesh_sta_info_get(sdata, mgmt->sa, &elems); 844 if (!sta) { 845 mpl_dbg(sdata, "Mesh plink: failed to init peer!\n"); 846 rcu_read_unlock(); 847 return; 848 } 849 } 850 851 mpl_dbg(sdata, "peer %pM in state %s got event %s\n", mgmt->sa, 852 mplstates[sta->plink_state], mplevents[event]); 853 reason = 0; 854 spin_lock_bh(&sta->lock); 855 switch (sta->plink_state) { 856 case NL80211_PLINK_LISTEN: 857 switch (event) { 858 case CLS_ACPT: 859 mesh_plink_fsm_restart(sta); 860 break; 861 case OPN_ACPT: 862 sta->plink_state = NL80211_PLINK_OPN_RCVD; 863 sta->plid = plid; 864 get_random_bytes(&llid, 2); 865 sta->llid = llid; 866 mesh_plink_timer_set(sta, 867 mshcfg->dot11MeshRetryTimeout); 868 869 /* set the non-peer mode to active during peering */ 870 changed |= ieee80211_mps_local_status_update(sdata); 871 872 action = WLAN_SP_MESH_PEERING_OPEN; 873 break; 874 default: 875 break; 876 } 877 break; 878 879 case NL80211_PLINK_OPN_SNT: 880 switch (event) { 881 case OPN_RJCT: 882 case CNF_RJCT: 883 reason = cpu_to_le16(WLAN_REASON_MESH_CONFIG); 884 case CLS_ACPT: 885 if (!reason) 886 reason = cpu_to_le16(WLAN_REASON_MESH_CLOSE); 887 sta->reason = reason; 888 sta->plink_state = NL80211_PLINK_HOLDING; 889 if (!mod_plink_timer(sta, 890 mshcfg->dot11MeshHoldingTimeout)) 891 sta->ignore_plink_timer = true; 892 893 action = WLAN_SP_MESH_PEERING_CLOSE; 894 break; 895 case OPN_ACPT: 896 /* retry timer is left untouched */ 897 sta->plink_state = NL80211_PLINK_OPN_RCVD; 898 sta->plid = plid; 899 action = WLAN_SP_MESH_PEERING_CONFIRM; 900 break; 901 case CNF_ACPT: 902 sta->plink_state = NL80211_PLINK_CNF_RCVD; 903 if (!mod_plink_timer(sta, 904 mshcfg->dot11MeshConfirmTimeout)) 905 sta->ignore_plink_timer = true; 906 907 break; 908 default: 909 break; 910 } 911 break; 912 913 case NL80211_PLINK_OPN_RCVD: 914 switch (event) { 915 case OPN_RJCT: 916 case CNF_RJCT: 917 reason = cpu_to_le16(WLAN_REASON_MESH_CONFIG); 918 case CLS_ACPT: 919 if (!reason) 920 reason = cpu_to_le16(WLAN_REASON_MESH_CLOSE); 921 sta->reason = reason; 922 sta->plink_state = NL80211_PLINK_HOLDING; 923 if (!mod_plink_timer(sta, 924 mshcfg->dot11MeshHoldingTimeout)) 925 sta->ignore_plink_timer = true; 926 927 action = WLAN_SP_MESH_PEERING_CLOSE; 928 break; 929 case OPN_ACPT: 930 action = WLAN_SP_MESH_PEERING_CONFIRM; 931 break; 932 case CNF_ACPT: 933 del_timer(&sta->plink_timer); 934 sta->plink_state = NL80211_PLINK_ESTAB; 935 changed |= mesh_plink_inc_estab_count(sdata); 936 changed |= mesh_set_ht_prot_mode(sdata); 937 changed |= mesh_set_short_slot_time(sdata); 938 mpl_dbg(sdata, "Mesh plink with %pM ESTABLISHED\n", 939 sta->sta.addr); 940 ieee80211_mps_sta_status_update(sta); 941 changed |= ieee80211_mps_set_sta_local_pm(sta, 942 mshcfg->power_mode); 943 break; 944 default: 945 break; 946 } 947 break; 948 949 case NL80211_PLINK_CNF_RCVD: 950 switch (event) { 951 case OPN_RJCT: 952 case CNF_RJCT: 953 reason = cpu_to_le16(WLAN_REASON_MESH_CONFIG); 954 case CLS_ACPT: 955 if (!reason) 956 reason = cpu_to_le16(WLAN_REASON_MESH_CLOSE); 957 sta->reason = reason; 958 sta->plink_state = NL80211_PLINK_HOLDING; 959 if (!mod_plink_timer(sta, 960 mshcfg->dot11MeshHoldingTimeout)) 961 sta->ignore_plink_timer = true; 962 963 action = WLAN_SP_MESH_PEERING_CLOSE; 964 break; 965 case OPN_ACPT: 966 del_timer(&sta->plink_timer); 967 sta->plink_state = NL80211_PLINK_ESTAB; 968 changed |= mesh_plink_inc_estab_count(sdata); 969 changed |= mesh_set_ht_prot_mode(sdata); 970 changed |= mesh_set_short_slot_time(sdata); 971 mpl_dbg(sdata, "Mesh plink with %pM ESTABLISHED\n", 972 sta->sta.addr); 973 action = WLAN_SP_MESH_PEERING_CONFIRM; 974 ieee80211_mps_sta_status_update(sta); 975 changed |= ieee80211_mps_set_sta_local_pm(sta, 976 mshcfg->power_mode); 977 break; 978 default: 979 break; 980 } 981 break; 982 983 case NL80211_PLINK_ESTAB: 984 switch (event) { 985 case CLS_ACPT: 986 reason = cpu_to_le16(WLAN_REASON_MESH_CLOSE); 987 sta->reason = reason; 988 changed |= __mesh_plink_deactivate(sta); 989 sta->plink_state = NL80211_PLINK_HOLDING; 990 mod_plink_timer(sta, mshcfg->dot11MeshHoldingTimeout); 991 changed |= mesh_set_ht_prot_mode(sdata); 992 changed |= mesh_set_short_slot_time(sdata); 993 action = WLAN_SP_MESH_PEERING_CLOSE; 994 break; 995 case OPN_ACPT: 996 action = WLAN_SP_MESH_PEERING_CONFIRM; 997 break; 998 default: 999 break; 1000 } 1001 break; 1002 case NL80211_PLINK_HOLDING: 1003 switch (event) { 1004 case CLS_ACPT: 1005 if (del_timer(&sta->plink_timer)) 1006 sta->ignore_plink_timer = 1; 1007 mesh_plink_fsm_restart(sta); 1008 break; 1009 case OPN_ACPT: 1010 case CNF_ACPT: 1011 case OPN_RJCT: 1012 case CNF_RJCT: 1013 action = WLAN_SP_MESH_PEERING_CLOSE; 1014 break; 1015 default: 1016 break; 1017 } 1018 break; 1019 default: 1020 /* should not get here, PLINK_BLOCKED is dealt with at the 1021 * beginning of the function 1022 */ 1023 break; 1024 } 1025 spin_unlock_bh(&sta->lock); 1026 if (action) { 1027 mesh_plink_frame_tx(sdata, action, sta->sta.addr, 1028 sta->llid, sta->plid, sta->reason); 1029 1030 /* also send confirm in open case */ 1031 if (action == WLAN_SP_MESH_PEERING_OPEN) { 1032 mesh_plink_frame_tx(sdata, 1033 WLAN_SP_MESH_PEERING_CONFIRM, 1034 sta->sta.addr, sta->llid, 1035 sta->plid, 0); 1036 } 1037 } 1038 1039 rcu_read_unlock(); 1040 1041 if (changed) 1042 ieee80211_mbss_info_change_notify(sdata, changed); 1043} 1044