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 8 #include <linux/slab.h> 9 #include <linux/etherdevice.h> 10 #include <linux/unaligned.h> 11 #include "wme.h" 12 #include "mesh.h" 13 14 #define TEST_FRAME_LEN 8192 15 #define MAX_METRIC 0xffffffff 16 #define ARITH_SHIFT 8 17 #define LINK_FAIL_THRESH 95 18 19 #define MAX_PREQ_QUEUE_LEN 64 20 21 static void mesh_queue_preq(struct mesh_path *, u8); 22 23 static inline u32 u32_field_get(const u8 *preq_elem, int offset, bool ae) 24 { 25 if (ae) 26 offset += 6; 27 return get_unaligned_le32(preq_elem + offset); 28 } 29 30 static inline u16 u16_field_get(const u8 *preq_elem, int offset, bool ae) 31 { 32 if (ae) 33 offset += 6; 34 return get_unaligned_le16(preq_elem + offset); 35 } 36 37 /* HWMP IE processing macros */ 38 #define AE_F (1<<6) 39 #define AE_F_SET(x) (*x & AE_F) 40 #define PREQ_IE_FLAGS(x) (*(x)) 41 #define PREQ_IE_HOPCOUNT(x) (*(x + 1)) 42 #define PREQ_IE_TTL(x) (*(x + 2)) 43 #define PREQ_IE_PREQ_ID(x) u32_field_get(x, 3, 0) 44 #define PREQ_IE_ORIG_ADDR(x) (x + 7) 45 #define PREQ_IE_ORIG_SN(x) u32_field_get(x, 13, 0) 46 #define PREQ_IE_LIFETIME(x) u32_field_get(x, 17, AE_F_SET(x)) 47 #define PREQ_IE_METRIC(x) u32_field_get(x, 21, AE_F_SET(x)) 48 #define PREQ_IE_TARGET_F(x) (*(AE_F_SET(x) ? x + 32 : x + 26)) 49 #define PREQ_IE_TARGET_ADDR(x) (AE_F_SET(x) ? x + 33 : x + 27) 50 #define PREQ_IE_TARGET_SN(x) u32_field_get(x, 33, AE_F_SET(x)) 51 52 53 #define PREP_IE_FLAGS(x) PREQ_IE_FLAGS(x) 54 #define PREP_IE_HOPCOUNT(x) PREQ_IE_HOPCOUNT(x) 55 #define PREP_IE_TTL(x) PREQ_IE_TTL(x) 56 #define PREP_IE_ORIG_ADDR(x) (AE_F_SET(x) ? x + 27 : x + 21) 57 #define PREP_IE_ORIG_SN(x) u32_field_get(x, 27, AE_F_SET(x)) 58 #define PREP_IE_LIFETIME(x) u32_field_get(x, 13, AE_F_SET(x)) 59 #define PREP_IE_METRIC(x) u32_field_get(x, 17, AE_F_SET(x)) 60 #define PREP_IE_TARGET_ADDR(x) (x + 3) 61 #define PREP_IE_TARGET_SN(x) u32_field_get(x, 9, 0) 62 63 #define PERR_IE_TTL(x) (*(x)) 64 #define PERR_IE_TARGET_FLAGS(x) (*(x + 2)) 65 #define PERR_IE_TARGET_ADDR(x) (x + 3) 66 #define PERR_IE_TARGET_SN(x) u32_field_get(x, 9, 0) 67 #define PERR_IE_TARGET_RCODE(x) u16_field_get(x, 13, 0) 68 69 #define MSEC_TO_TU(x) (x*1000/1024) 70 #define SN_GT(x, y) ((s32)(y - x) < 0) 71 #define SN_LT(x, y) ((s32)(x - y) < 0) 72 #define MAX_SANE_SN_DELTA 32 73 74 static inline u32 SN_DELTA(u32 x, u32 y) 75 { 76 return x >= y ? x - y : y - x; 77 } 78 79 #define net_traversal_jiffies(s) \ 80 msecs_to_jiffies(s->u.mesh.mshcfg.dot11MeshHWMPnetDiameterTraversalTime) 81 #define default_lifetime(s) \ 82 MSEC_TO_TU(s->u.mesh.mshcfg.dot11MeshHWMPactivePathTimeout) 83 #define min_preq_int_jiff(s) \ 84 (msecs_to_jiffies(s->u.mesh.mshcfg.dot11MeshHWMPpreqMinInterval)) 85 #define max_preq_retries(s) (s->u.mesh.mshcfg.dot11MeshHWMPmaxPREQretries) 86 #define disc_timeout_jiff(s) \ 87 msecs_to_jiffies(sdata->u.mesh.mshcfg.min_discovery_timeout) 88 #define root_path_confirmation_jiffies(s) \ 89 msecs_to_jiffies(sdata->u.mesh.mshcfg.dot11MeshHWMPconfirmationInterval) 90 91 enum mpath_frame_type { 92 MPATH_PREQ = 0, 93 MPATH_PREP, 94 MPATH_PERR, 95 MPATH_RANN 96 }; 97 98 static const u8 broadcast_addr[ETH_ALEN] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff}; 99 100 static int mesh_path_sel_frame_tx(enum mpath_frame_type action, u8 flags, 101 const u8 *orig_addr, u32 orig_sn, 102 u8 target_flags, const u8 *target, 103 u32 target_sn, const u8 *da, 104 u8 hop_count, u8 ttl, 105 u32 lifetime, u32 metric, u32 preq_id, 106 struct ieee80211_sub_if_data *sdata) 107 { 108 struct ieee80211_local *local = sdata->local; 109 struct sk_buff *skb; 110 struct ieee80211_mgmt *mgmt; 111 u8 *pos, ie_len; 112 int hdr_len = offsetofend(struct ieee80211_mgmt, 113 u.action.u.mesh_action); 114 115 skb = dev_alloc_skb(local->tx_headroom + 116 hdr_len + 117 2 + 37); /* max HWMP IE */ 118 if (!skb) 119 return -1; 120 skb_reserve(skb, local->tx_headroom); 121 mgmt = skb_put_zero(skb, hdr_len); 122 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 123 IEEE80211_STYPE_ACTION); 124 125 memcpy(mgmt->da, da, ETH_ALEN); 126 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN); 127 /* BSSID == SA */ 128 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN); 129 mgmt->u.action.category = WLAN_CATEGORY_MESH_ACTION; 130 mgmt->u.action.u.mesh_action.action_code = 131 WLAN_MESH_ACTION_HWMP_PATH_SELECTION; 132 133 switch (action) { 134 case MPATH_PREQ: 135 mhwmp_dbg(sdata, "sending PREQ to %pM\n", target); 136 ie_len = 37; 137 pos = skb_put(skb, 2 + ie_len); 138 *pos++ = WLAN_EID_PREQ; 139 break; 140 case MPATH_PREP: 141 mhwmp_dbg(sdata, "sending PREP to %pM\n", orig_addr); 142 ie_len = 31; 143 pos = skb_put(skb, 2 + ie_len); 144 *pos++ = WLAN_EID_PREP; 145 break; 146 case MPATH_RANN: 147 mhwmp_dbg(sdata, "sending RANN from %pM\n", orig_addr); 148 ie_len = sizeof(struct ieee80211_rann_ie); 149 pos = skb_put(skb, 2 + ie_len); 150 *pos++ = WLAN_EID_RANN; 151 break; 152 default: 153 kfree_skb(skb); 154 return -EOPNOTSUPP; 155 } 156 *pos++ = ie_len; 157 *pos++ = flags; 158 *pos++ = hop_count; 159 *pos++ = ttl; 160 if (action == MPATH_PREP) { 161 memcpy(pos, target, ETH_ALEN); 162 pos += ETH_ALEN; 163 put_unaligned_le32(target_sn, pos); 164 pos += 4; 165 } else { 166 if (action == MPATH_PREQ) { 167 put_unaligned_le32(preq_id, pos); 168 pos += 4; 169 } 170 memcpy(pos, orig_addr, ETH_ALEN); 171 pos += ETH_ALEN; 172 put_unaligned_le32(orig_sn, pos); 173 pos += 4; 174 } 175 put_unaligned_le32(lifetime, pos); /* interval for RANN */ 176 pos += 4; 177 put_unaligned_le32(metric, pos); 178 pos += 4; 179 if (action == MPATH_PREQ) { 180 *pos++ = 1; /* destination count */ 181 *pos++ = target_flags; 182 memcpy(pos, target, ETH_ALEN); 183 pos += ETH_ALEN; 184 put_unaligned_le32(target_sn, pos); 185 pos += 4; 186 } else if (action == MPATH_PREP) { 187 memcpy(pos, orig_addr, ETH_ALEN); 188 pos += ETH_ALEN; 189 put_unaligned_le32(orig_sn, pos); 190 pos += 4; 191 } 192 193 ieee80211_tx_skb(sdata, skb); 194 return 0; 195 } 196 197 198 /* Headroom is not adjusted. Caller should ensure that skb has sufficient 199 * headroom in case the frame is encrypted. */ 200 static void prepare_frame_for_deferred_tx(struct ieee80211_sub_if_data *sdata, 201 struct sk_buff *skb) 202 { 203 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 204 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 205 206 skb_reset_mac_header(skb); 207 skb_reset_network_header(skb); 208 skb_reset_transport_header(skb); 209 210 /* Send all internal mgmt frames on VO. Accordingly set TID to 7. */ 211 skb_set_queue_mapping(skb, IEEE80211_AC_VO); 212 skb->priority = 7; 213 214 info->control.vif = &sdata->vif; 215 info->control.flags |= IEEE80211_TX_INTCFL_NEED_TXPROCESSING; 216 ieee80211_set_qos_hdr(sdata, skb); 217 ieee80211_mps_set_frame_flags(sdata, NULL, hdr); 218 } 219 220 /** 221 * mesh_path_error_tx - Sends a PERR mesh management frame 222 * 223 * @sdata: local mesh subif 224 * @ttl: allowed remaining hops 225 * @target: broken destination 226 * @target_sn: SN of the broken destination 227 * @target_rcode: reason code for this PERR 228 * @ra: node this frame is addressed to 229 * 230 * Note: This function may be called with driver locks taken that the driver 231 * also acquires in the TX path. To avoid a deadlock we don't transmit the 232 * frame directly but add it to the pending queue instead. 233 * 234 * Returns: 0 on success 235 */ 236 int mesh_path_error_tx(struct ieee80211_sub_if_data *sdata, 237 u8 ttl, const u8 *target, u32 target_sn, 238 u16 target_rcode, const u8 *ra) 239 { 240 struct ieee80211_local *local = sdata->local; 241 struct sk_buff *skb; 242 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 243 struct ieee80211_mgmt *mgmt; 244 u8 *pos, ie_len; 245 int hdr_len = offsetofend(struct ieee80211_mgmt, 246 u.action.u.mesh_action); 247 248 if (time_before(jiffies, ifmsh->next_perr)) 249 return -EAGAIN; 250 251 skb = dev_alloc_skb(local->tx_headroom + 252 IEEE80211_ENCRYPT_HEADROOM + 253 IEEE80211_ENCRYPT_TAILROOM + 254 hdr_len + 255 2 + 15 /* PERR IE */); 256 if (!skb) 257 return -1; 258 skb_reserve(skb, local->tx_headroom + IEEE80211_ENCRYPT_HEADROOM); 259 mgmt = skb_put_zero(skb, hdr_len); 260 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 261 IEEE80211_STYPE_ACTION); 262 263 memcpy(mgmt->da, ra, ETH_ALEN); 264 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN); 265 /* BSSID == SA */ 266 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN); 267 mgmt->u.action.category = WLAN_CATEGORY_MESH_ACTION; 268 mgmt->u.action.u.mesh_action.action_code = 269 WLAN_MESH_ACTION_HWMP_PATH_SELECTION; 270 ie_len = 15; 271 pos = skb_put(skb, 2 + ie_len); 272 *pos++ = WLAN_EID_PERR; 273 *pos++ = ie_len; 274 /* ttl */ 275 *pos++ = ttl; 276 /* number of destinations */ 277 *pos++ = 1; 278 /* Flags field has AE bit only as defined in 279 * sec 8.4.2.117 IEEE802.11-2012 280 */ 281 *pos = 0; 282 pos++; 283 memcpy(pos, target, ETH_ALEN); 284 pos += ETH_ALEN; 285 put_unaligned_le32(target_sn, pos); 286 pos += 4; 287 put_unaligned_le16(target_rcode, pos); 288 289 /* see note in function header */ 290 prepare_frame_for_deferred_tx(sdata, skb); 291 ifmsh->next_perr = TU_TO_EXP_TIME( 292 ifmsh->mshcfg.dot11MeshHWMPperrMinInterval); 293 ieee80211_add_pending_skb(local, skb); 294 return 0; 295 } 296 297 void ieee80211s_update_metric(struct ieee80211_local *local, 298 struct sta_info *sta, 299 struct ieee80211_tx_status *st) 300 { 301 struct ieee80211_tx_info *txinfo = st->info; 302 int failed; 303 struct rate_info rinfo; 304 305 failed = !(txinfo->flags & IEEE80211_TX_STAT_ACK); 306 307 /* moving average, scaled to 100. 308 * feed failure as 100 and success as 0 309 */ 310 ewma_mesh_fail_avg_add(&sta->mesh->fail_avg, failed * 100); 311 if (ewma_mesh_fail_avg_read(&sta->mesh->fail_avg) > 312 LINK_FAIL_THRESH) 313 mesh_plink_broken(sta); 314 315 /* use rate info set by the driver directly if present */ 316 if (st->n_rates) 317 rinfo = sta->deflink.tx_stats.last_rate_info; 318 else 319 sta_set_rate_info_tx(sta, &sta->deflink.tx_stats.last_rate, &rinfo); 320 321 ewma_mesh_tx_rate_avg_add(&sta->mesh->tx_rate_avg, 322 cfg80211_calculate_bitrate(&rinfo)); 323 } 324 325 u32 airtime_link_metric_get(struct ieee80211_local *local, 326 struct sta_info *sta) 327 { 328 /* This should be adjusted for each device */ 329 int device_constant = 1 << ARITH_SHIFT; 330 int test_frame_len = TEST_FRAME_LEN << ARITH_SHIFT; 331 int s_unit = 1 << ARITH_SHIFT; 332 int rate, err; 333 u32 tx_time, estimated_retx; 334 u64 result; 335 unsigned long fail_avg = 336 ewma_mesh_fail_avg_read(&sta->mesh->fail_avg); 337 338 if (sta->mesh->plink_state != NL80211_PLINK_ESTAB) 339 return MAX_METRIC; 340 341 /* Try to get rate based on HW/SW RC algorithm. 342 * Rate is returned in units of Kbps, correct this 343 * to comply with airtime calculation units 344 * Round up in case we get rate < 100Kbps 345 */ 346 rate = DIV_ROUND_UP(sta_get_expected_throughput(sta), 100); 347 348 if (rate) { 349 err = 0; 350 } else { 351 if (fail_avg > LINK_FAIL_THRESH) 352 return MAX_METRIC; 353 354 rate = ewma_mesh_tx_rate_avg_read(&sta->mesh->tx_rate_avg); 355 if (WARN_ON(!rate)) 356 return MAX_METRIC; 357 358 err = (fail_avg << ARITH_SHIFT) / 100; 359 } 360 361 /* bitrate is in units of 100 Kbps, while we need rate in units of 362 * 1Mbps. This will be corrected on tx_time computation. 363 */ 364 tx_time = (device_constant + 10 * test_frame_len / rate); 365 estimated_retx = ((1 << (2 * ARITH_SHIFT)) / (s_unit - err)); 366 result = ((u64)tx_time * estimated_retx) >> (2 * ARITH_SHIFT); 367 return (u32)result; 368 } 369 370 /* Check that the first metric is at least 10% better than the second one */ 371 static bool is_metric_better(u32 x, u32 y) 372 { 373 return (x < y) && (x < (y - x / 10)); 374 } 375 376 /** 377 * hwmp_route_info_get - Update routing info to originator and transmitter 378 * 379 * @sdata: local mesh subif 380 * @mgmt: mesh management frame 381 * @hwmp_ie: hwmp information element (PREP or PREQ) 382 * @action: type of hwmp ie 383 * 384 * This function updates the path routing information to the originator and the 385 * transmitter of a HWMP PREQ or PREP frame. 386 * 387 * Returns: metric to frame originator or 0 if the frame should not be further 388 * processed 389 * 390 * Notes: this function is the only place (besides user-provided info) where 391 * path routing information is updated. 392 */ 393 static u32 hwmp_route_info_get(struct ieee80211_sub_if_data *sdata, 394 struct ieee80211_mgmt *mgmt, 395 const u8 *hwmp_ie, enum mpath_frame_type action) 396 { 397 struct ieee80211_local *local = sdata->local; 398 struct mesh_path *mpath; 399 struct sta_info *sta; 400 bool fresh_info; 401 const u8 *orig_addr, *ta; 402 u32 orig_sn, orig_metric; 403 unsigned long orig_lifetime, exp_time; 404 u32 last_hop_metric, new_metric; 405 bool flush_mpath = false; 406 bool process = true; 407 u8 hopcount; 408 409 rcu_read_lock(); 410 sta = sta_info_get(sdata, mgmt->sa); 411 if (!sta) { 412 rcu_read_unlock(); 413 return 0; 414 } 415 416 last_hop_metric = airtime_link_metric_get(local, sta); 417 /* Update and check originator routing info */ 418 fresh_info = true; 419 420 switch (action) { 421 case MPATH_PREQ: 422 orig_addr = PREQ_IE_ORIG_ADDR(hwmp_ie); 423 orig_sn = PREQ_IE_ORIG_SN(hwmp_ie); 424 orig_lifetime = PREQ_IE_LIFETIME(hwmp_ie); 425 orig_metric = PREQ_IE_METRIC(hwmp_ie); 426 hopcount = PREQ_IE_HOPCOUNT(hwmp_ie) + 1; 427 break; 428 case MPATH_PREP: 429 /* Originator here refers to the MP that was the target in the 430 * Path Request. We divert from the nomenclature in the draft 431 * so that we can easily use a single function to gather path 432 * information from both PREQ and PREP frames. 433 */ 434 orig_addr = PREP_IE_TARGET_ADDR(hwmp_ie); 435 orig_sn = PREP_IE_TARGET_SN(hwmp_ie); 436 orig_lifetime = PREP_IE_LIFETIME(hwmp_ie); 437 orig_metric = PREP_IE_METRIC(hwmp_ie); 438 hopcount = PREP_IE_HOPCOUNT(hwmp_ie) + 1; 439 break; 440 default: 441 rcu_read_unlock(); 442 return 0; 443 } 444 new_metric = orig_metric + last_hop_metric; 445 if (new_metric < orig_metric) 446 new_metric = MAX_METRIC; 447 exp_time = TU_TO_EXP_TIME(orig_lifetime); 448 449 if (ether_addr_equal(orig_addr, sdata->vif.addr)) { 450 /* This MP is the originator, we are not interested in this 451 * frame, except for updating transmitter's path info. 452 */ 453 process = false; 454 fresh_info = false; 455 } else { 456 mpath = mesh_path_lookup(sdata, orig_addr); 457 if (mpath) { 458 spin_lock_bh(&mpath->state_lock); 459 if (mpath->flags & MESH_PATH_FIXED) 460 fresh_info = false; 461 else if ((mpath->flags & MESH_PATH_ACTIVE) && 462 (mpath->flags & MESH_PATH_SN_VALID)) { 463 if (SN_GT(mpath->sn, orig_sn) || 464 (mpath->sn == orig_sn && 465 (rcu_access_pointer(mpath->next_hop) != 466 sta ? 467 !is_metric_better(new_metric, mpath->metric) : 468 new_metric >= mpath->metric))) { 469 process = false; 470 fresh_info = false; 471 } 472 } else if (!(mpath->flags & MESH_PATH_ACTIVE)) { 473 bool have_sn, newer_sn, bounced; 474 475 have_sn = mpath->flags & MESH_PATH_SN_VALID; 476 newer_sn = have_sn && SN_GT(orig_sn, mpath->sn); 477 bounced = have_sn && 478 (SN_DELTA(orig_sn, mpath->sn) > 479 MAX_SANE_SN_DELTA); 480 481 if (!have_sn || newer_sn) { 482 /* if SN is newer than what we had 483 * then we can take it */; 484 } else if (bounced) { 485 /* if SN is way different than what 486 * we had then assume the other side 487 * rebooted or restarted */; 488 } else { 489 process = false; 490 fresh_info = false; 491 } 492 } 493 } else { 494 mpath = mesh_path_add(sdata, orig_addr); 495 if (IS_ERR(mpath)) { 496 rcu_read_unlock(); 497 return 0; 498 } 499 spin_lock_bh(&mpath->state_lock); 500 } 501 502 if (fresh_info) { 503 if (rcu_access_pointer(mpath->next_hop) != sta) { 504 mpath->path_change_count++; 505 flush_mpath = true; 506 } 507 mesh_path_assign_nexthop(mpath, sta); 508 mpath->flags |= MESH_PATH_SN_VALID; 509 mpath->metric = new_metric; 510 mpath->sn = orig_sn; 511 mpath->exp_time = time_after(mpath->exp_time, exp_time) 512 ? mpath->exp_time : exp_time; 513 mpath->hop_count = hopcount; 514 mesh_path_activate(mpath); 515 spin_unlock_bh(&mpath->state_lock); 516 if (flush_mpath) 517 mesh_fast_tx_flush_mpath(mpath); 518 ewma_mesh_fail_avg_init(&sta->mesh->fail_avg); 519 /* init it at a low value - 0 start is tricky */ 520 ewma_mesh_fail_avg_add(&sta->mesh->fail_avg, 1); 521 mesh_path_tx_pending(mpath); 522 /* draft says preq_id should be saved to, but there does 523 * not seem to be any use for it, skipping by now 524 */ 525 } else 526 spin_unlock_bh(&mpath->state_lock); 527 } 528 529 /* Update and check transmitter routing info */ 530 ta = mgmt->sa; 531 if (ether_addr_equal(orig_addr, ta)) 532 fresh_info = false; 533 else { 534 fresh_info = true; 535 536 mpath = mesh_path_lookup(sdata, ta); 537 if (mpath) { 538 spin_lock_bh(&mpath->state_lock); 539 if ((mpath->flags & MESH_PATH_FIXED) || 540 ((mpath->flags & MESH_PATH_ACTIVE) && 541 ((rcu_access_pointer(mpath->next_hop) != sta ? 542 !is_metric_better(last_hop_metric, mpath->metric) : 543 last_hop_metric > mpath->metric)))) 544 fresh_info = false; 545 } else { 546 mpath = mesh_path_add(sdata, ta); 547 if (IS_ERR(mpath)) { 548 rcu_read_unlock(); 549 return 0; 550 } 551 spin_lock_bh(&mpath->state_lock); 552 } 553 554 if (fresh_info) { 555 if (rcu_access_pointer(mpath->next_hop) != sta) { 556 mpath->path_change_count++; 557 flush_mpath = true; 558 } 559 mesh_path_assign_nexthop(mpath, sta); 560 mpath->metric = last_hop_metric; 561 mpath->exp_time = time_after(mpath->exp_time, exp_time) 562 ? mpath->exp_time : exp_time; 563 mpath->hop_count = 1; 564 mesh_path_activate(mpath); 565 spin_unlock_bh(&mpath->state_lock); 566 if (flush_mpath) 567 mesh_fast_tx_flush_mpath(mpath); 568 ewma_mesh_fail_avg_init(&sta->mesh->fail_avg); 569 /* init it at a low value - 0 start is tricky */ 570 ewma_mesh_fail_avg_add(&sta->mesh->fail_avg, 1); 571 mesh_path_tx_pending(mpath); 572 } else 573 spin_unlock_bh(&mpath->state_lock); 574 } 575 576 rcu_read_unlock(); 577 578 return process ? new_metric : 0; 579 } 580 581 static void hwmp_preq_frame_process(struct ieee80211_sub_if_data *sdata, 582 struct ieee80211_mgmt *mgmt, 583 const u8 *preq_elem, u32 orig_metric) 584 { 585 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 586 struct mesh_path *mpath = NULL; 587 const u8 *target_addr, *orig_addr; 588 const u8 *da; 589 u8 target_flags, ttl, flags; 590 u32 orig_sn, target_sn, lifetime, target_metric = 0; 591 bool reply = false; 592 bool forward = true; 593 bool root_is_gate; 594 595 /* Update target SN, if present */ 596 target_addr = PREQ_IE_TARGET_ADDR(preq_elem); 597 orig_addr = PREQ_IE_ORIG_ADDR(preq_elem); 598 target_sn = PREQ_IE_TARGET_SN(preq_elem); 599 orig_sn = PREQ_IE_ORIG_SN(preq_elem); 600 target_flags = PREQ_IE_TARGET_F(preq_elem); 601 /* Proactive PREQ gate announcements */ 602 flags = PREQ_IE_FLAGS(preq_elem); 603 root_is_gate = !!(flags & RANN_FLAG_IS_GATE); 604 605 mhwmp_dbg(sdata, "received PREQ from %pM\n", orig_addr); 606 607 if (ether_addr_equal(target_addr, sdata->vif.addr)) { 608 mhwmp_dbg(sdata, "PREQ is for us\n"); 609 forward = false; 610 reply = true; 611 target_metric = 0; 612 613 if (SN_GT(target_sn, ifmsh->sn)) 614 ifmsh->sn = target_sn; 615 616 if (time_after(jiffies, ifmsh->last_sn_update + 617 net_traversal_jiffies(sdata)) || 618 time_before(jiffies, ifmsh->last_sn_update)) { 619 ++ifmsh->sn; 620 ifmsh->last_sn_update = jiffies; 621 } 622 target_sn = ifmsh->sn; 623 } else if (is_broadcast_ether_addr(target_addr) && 624 (target_flags & IEEE80211_PREQ_TO_FLAG)) { 625 rcu_read_lock(); 626 mpath = mesh_path_lookup(sdata, orig_addr); 627 if (mpath) { 628 if (flags & IEEE80211_PREQ_PROACTIVE_PREP_FLAG) { 629 reply = true; 630 target_addr = sdata->vif.addr; 631 target_sn = ++ifmsh->sn; 632 target_metric = 0; 633 ifmsh->last_sn_update = jiffies; 634 } 635 if (root_is_gate) 636 mesh_path_add_gate(mpath); 637 } 638 rcu_read_unlock(); 639 } else if (ifmsh->mshcfg.dot11MeshForwarding) { 640 rcu_read_lock(); 641 mpath = mesh_path_lookup(sdata, target_addr); 642 if (mpath) { 643 if ((!(mpath->flags & MESH_PATH_SN_VALID)) || 644 SN_LT(mpath->sn, target_sn)) { 645 mpath->sn = target_sn; 646 mpath->flags |= MESH_PATH_SN_VALID; 647 } else if ((!(target_flags & IEEE80211_PREQ_TO_FLAG)) && 648 (mpath->flags & MESH_PATH_ACTIVE)) { 649 reply = true; 650 target_metric = mpath->metric; 651 target_sn = mpath->sn; 652 /* Case E2 of sec 13.10.9.3 IEEE 802.11-2012*/ 653 target_flags |= IEEE80211_PREQ_TO_FLAG; 654 } 655 } 656 rcu_read_unlock(); 657 } else { 658 forward = false; 659 } 660 661 if (reply) { 662 lifetime = PREQ_IE_LIFETIME(preq_elem); 663 ttl = ifmsh->mshcfg.element_ttl; 664 if (ttl != 0) { 665 mhwmp_dbg(sdata, "replying to the PREQ\n"); 666 mesh_path_sel_frame_tx(MPATH_PREP, 0, orig_addr, 667 orig_sn, 0, target_addr, 668 target_sn, mgmt->sa, 0, ttl, 669 lifetime, target_metric, 0, 670 sdata); 671 } else { 672 ifmsh->mshstats.dropped_frames_ttl++; 673 } 674 } 675 676 if (forward) { 677 u32 preq_id; 678 u8 hopcount; 679 680 ttl = PREQ_IE_TTL(preq_elem); 681 lifetime = PREQ_IE_LIFETIME(preq_elem); 682 if (ttl <= 1) { 683 ifmsh->mshstats.dropped_frames_ttl++; 684 return; 685 } 686 mhwmp_dbg(sdata, "forwarding the PREQ from %pM\n", orig_addr); 687 --ttl; 688 preq_id = PREQ_IE_PREQ_ID(preq_elem); 689 hopcount = PREQ_IE_HOPCOUNT(preq_elem) + 1; 690 da = (mpath && mpath->is_root) ? 691 mpath->rann_snd_addr : broadcast_addr; 692 693 if (flags & IEEE80211_PREQ_PROACTIVE_PREP_FLAG) { 694 target_addr = PREQ_IE_TARGET_ADDR(preq_elem); 695 target_sn = PREQ_IE_TARGET_SN(preq_elem); 696 } 697 698 mesh_path_sel_frame_tx(MPATH_PREQ, flags, orig_addr, 699 orig_sn, target_flags, target_addr, 700 target_sn, da, hopcount, ttl, lifetime, 701 orig_metric, preq_id, sdata); 702 if (!is_multicast_ether_addr(da)) 703 ifmsh->mshstats.fwded_unicast++; 704 else 705 ifmsh->mshstats.fwded_mcast++; 706 ifmsh->mshstats.fwded_frames++; 707 } 708 } 709 710 711 static inline struct sta_info * 712 next_hop_deref_protected(struct mesh_path *mpath) 713 { 714 return rcu_dereference_protected(mpath->next_hop, 715 lockdep_is_held(&mpath->state_lock)); 716 } 717 718 719 static void hwmp_prep_frame_process(struct ieee80211_sub_if_data *sdata, 720 struct ieee80211_mgmt *mgmt, 721 const u8 *prep_elem, u32 metric) 722 { 723 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 724 struct mesh_path *mpath; 725 const u8 *target_addr, *orig_addr; 726 u8 ttl, hopcount, flags; 727 u8 next_hop[ETH_ALEN]; 728 u32 target_sn, orig_sn, lifetime; 729 730 mhwmp_dbg(sdata, "received PREP from %pM\n", 731 PREP_IE_TARGET_ADDR(prep_elem)); 732 733 orig_addr = PREP_IE_ORIG_ADDR(prep_elem); 734 if (ether_addr_equal(orig_addr, sdata->vif.addr)) 735 /* destination, no forwarding required */ 736 return; 737 738 if (!ifmsh->mshcfg.dot11MeshForwarding) 739 return; 740 741 ttl = PREP_IE_TTL(prep_elem); 742 if (ttl <= 1) { 743 sdata->u.mesh.mshstats.dropped_frames_ttl++; 744 return; 745 } 746 747 rcu_read_lock(); 748 mpath = mesh_path_lookup(sdata, orig_addr); 749 if (mpath) 750 spin_lock_bh(&mpath->state_lock); 751 else 752 goto fail; 753 if (!(mpath->flags & MESH_PATH_ACTIVE)) { 754 spin_unlock_bh(&mpath->state_lock); 755 goto fail; 756 } 757 memcpy(next_hop, next_hop_deref_protected(mpath)->sta.addr, ETH_ALEN); 758 spin_unlock_bh(&mpath->state_lock); 759 --ttl; 760 flags = PREP_IE_FLAGS(prep_elem); 761 lifetime = PREP_IE_LIFETIME(prep_elem); 762 hopcount = PREP_IE_HOPCOUNT(prep_elem) + 1; 763 target_addr = PREP_IE_TARGET_ADDR(prep_elem); 764 target_sn = PREP_IE_TARGET_SN(prep_elem); 765 orig_sn = PREP_IE_ORIG_SN(prep_elem); 766 767 mesh_path_sel_frame_tx(MPATH_PREP, flags, orig_addr, orig_sn, 0, 768 target_addr, target_sn, next_hop, hopcount, 769 ttl, lifetime, metric, 0, sdata); 770 rcu_read_unlock(); 771 772 sdata->u.mesh.mshstats.fwded_unicast++; 773 sdata->u.mesh.mshstats.fwded_frames++; 774 return; 775 776 fail: 777 rcu_read_unlock(); 778 sdata->u.mesh.mshstats.dropped_frames_no_route++; 779 } 780 781 static void hwmp_perr_frame_process(struct ieee80211_sub_if_data *sdata, 782 struct ieee80211_mgmt *mgmt, 783 const u8 *perr_elem) 784 { 785 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 786 struct mesh_path *mpath; 787 u8 ttl; 788 const u8 *ta, *target_addr; 789 u32 target_sn; 790 u16 target_rcode; 791 792 ta = mgmt->sa; 793 ttl = PERR_IE_TTL(perr_elem); 794 if (ttl <= 1) { 795 ifmsh->mshstats.dropped_frames_ttl++; 796 return; 797 } 798 ttl--; 799 target_addr = PERR_IE_TARGET_ADDR(perr_elem); 800 target_sn = PERR_IE_TARGET_SN(perr_elem); 801 target_rcode = PERR_IE_TARGET_RCODE(perr_elem); 802 803 rcu_read_lock(); 804 mpath = mesh_path_lookup(sdata, target_addr); 805 if (mpath) { 806 struct sta_info *sta; 807 808 spin_lock_bh(&mpath->state_lock); 809 sta = next_hop_deref_protected(mpath); 810 if (mpath->flags & MESH_PATH_ACTIVE && 811 ether_addr_equal(ta, sta->sta.addr) && 812 !(mpath->flags & MESH_PATH_FIXED) && 813 (!(mpath->flags & MESH_PATH_SN_VALID) || 814 SN_GT(target_sn, mpath->sn) || target_sn == 0)) { 815 mpath->flags &= ~MESH_PATH_ACTIVE; 816 if (target_sn != 0) 817 mpath->sn = target_sn; 818 else 819 mpath->sn += 1; 820 spin_unlock_bh(&mpath->state_lock); 821 if (!ifmsh->mshcfg.dot11MeshForwarding) 822 goto endperr; 823 mesh_path_error_tx(sdata, ttl, target_addr, 824 target_sn, target_rcode, 825 broadcast_addr); 826 } else 827 spin_unlock_bh(&mpath->state_lock); 828 } 829 endperr: 830 rcu_read_unlock(); 831 } 832 833 static void hwmp_rann_frame_process(struct ieee80211_sub_if_data *sdata, 834 struct ieee80211_mgmt *mgmt, 835 const struct ieee80211_rann_ie *rann) 836 { 837 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 838 struct ieee80211_local *local = sdata->local; 839 struct sta_info *sta; 840 struct mesh_path *mpath; 841 u8 ttl, flags, hopcount; 842 const u8 *orig_addr; 843 u32 orig_sn, new_metric, orig_metric, last_hop_metric, interval; 844 bool root_is_gate; 845 846 ttl = rann->rann_ttl; 847 flags = rann->rann_flags; 848 root_is_gate = !!(flags & RANN_FLAG_IS_GATE); 849 orig_addr = rann->rann_addr; 850 orig_sn = le32_to_cpu(rann->rann_seq); 851 interval = le32_to_cpu(rann->rann_interval); 852 hopcount = rann->rann_hopcount; 853 hopcount++; 854 orig_metric = le32_to_cpu(rann->rann_metric); 855 856 /* Ignore our own RANNs */ 857 if (ether_addr_equal(orig_addr, sdata->vif.addr)) 858 return; 859 860 mhwmp_dbg(sdata, 861 "received RANN from %pM via neighbour %pM (is_gate=%d)\n", 862 orig_addr, mgmt->sa, root_is_gate); 863 864 rcu_read_lock(); 865 sta = sta_info_get(sdata, mgmt->sa); 866 if (!sta) { 867 rcu_read_unlock(); 868 return; 869 } 870 871 last_hop_metric = airtime_link_metric_get(local, sta); 872 new_metric = orig_metric + last_hop_metric; 873 if (new_metric < orig_metric) 874 new_metric = MAX_METRIC; 875 876 mpath = mesh_path_lookup(sdata, orig_addr); 877 if (!mpath) { 878 mpath = mesh_path_add(sdata, orig_addr); 879 if (IS_ERR(mpath)) { 880 rcu_read_unlock(); 881 sdata->u.mesh.mshstats.dropped_frames_no_route++; 882 return; 883 } 884 } 885 886 if (!(SN_LT(mpath->sn, orig_sn)) && 887 !(mpath->sn == orig_sn && new_metric < mpath->rann_metric)) { 888 rcu_read_unlock(); 889 return; 890 } 891 892 if ((!(mpath->flags & (MESH_PATH_ACTIVE | MESH_PATH_RESOLVING)) || 893 (time_after(jiffies, mpath->last_preq_to_root + 894 root_path_confirmation_jiffies(sdata)) || 895 time_before(jiffies, mpath->last_preq_to_root))) && 896 !(mpath->flags & MESH_PATH_FIXED) && (ttl != 0)) { 897 mhwmp_dbg(sdata, 898 "time to refresh root mpath %pM\n", 899 orig_addr); 900 mesh_queue_preq(mpath, PREQ_Q_F_START | PREQ_Q_F_REFRESH); 901 mpath->last_preq_to_root = jiffies; 902 } 903 904 mpath->sn = orig_sn; 905 mpath->rann_metric = new_metric; 906 mpath->is_root = true; 907 /* Recording RANNs sender address to send individually 908 * addressed PREQs destined for root mesh STA */ 909 memcpy(mpath->rann_snd_addr, mgmt->sa, ETH_ALEN); 910 911 if (root_is_gate) 912 mesh_path_add_gate(mpath); 913 914 if (ttl <= 1) { 915 ifmsh->mshstats.dropped_frames_ttl++; 916 rcu_read_unlock(); 917 return; 918 } 919 ttl--; 920 921 if (ifmsh->mshcfg.dot11MeshForwarding) { 922 mesh_path_sel_frame_tx(MPATH_RANN, flags, orig_addr, 923 orig_sn, 0, NULL, 0, broadcast_addr, 924 hopcount, ttl, interval, 925 new_metric, 0, sdata); 926 } 927 928 rcu_read_unlock(); 929 } 930 931 932 void mesh_rx_path_sel_frame(struct ieee80211_sub_if_data *sdata, 933 struct ieee80211_mgmt *mgmt, size_t len) 934 { 935 struct ieee802_11_elems *elems; 936 size_t baselen; 937 u32 path_metric; 938 struct sta_info *sta; 939 940 /* need action_code */ 941 if (len < IEEE80211_MIN_ACTION_SIZE + 1) 942 return; 943 944 rcu_read_lock(); 945 sta = sta_info_get(sdata, mgmt->sa); 946 if (!sta || sta->mesh->plink_state != NL80211_PLINK_ESTAB) { 947 rcu_read_unlock(); 948 return; 949 } 950 rcu_read_unlock(); 951 952 baselen = (u8 *) mgmt->u.action.u.mesh_action.variable - (u8 *) mgmt; 953 elems = ieee802_11_parse_elems(mgmt->u.action.u.mesh_action.variable, 954 len - baselen, false, NULL); 955 if (!elems) 956 return; 957 958 if (elems->preq) { 959 if (elems->preq_len != 37) 960 /* Right now we support just 1 destination and no AE */ 961 goto free; 962 path_metric = hwmp_route_info_get(sdata, mgmt, elems->preq, 963 MPATH_PREQ); 964 if (path_metric) 965 hwmp_preq_frame_process(sdata, mgmt, elems->preq, 966 path_metric); 967 } 968 if (elems->prep) { 969 if (elems->prep_len != 31) 970 /* Right now we support no AE */ 971 goto free; 972 path_metric = hwmp_route_info_get(sdata, mgmt, elems->prep, 973 MPATH_PREP); 974 if (path_metric) 975 hwmp_prep_frame_process(sdata, mgmt, elems->prep, 976 path_metric); 977 } 978 if (elems->perr) { 979 if (elems->perr_len != 15) 980 /* Right now we support only one destination per PERR */ 981 goto free; 982 hwmp_perr_frame_process(sdata, mgmt, elems->perr); 983 } 984 if (elems->rann) 985 hwmp_rann_frame_process(sdata, mgmt, elems->rann); 986 free: 987 kfree(elems); 988 } 989 990 /** 991 * mesh_queue_preq - queue a PREQ to a given destination 992 * 993 * @mpath: mesh path to discover 994 * @flags: special attributes of the PREQ to be sent 995 * 996 * Locking: the function must be called from within a rcu read lock block. 997 * 998 */ 999 static void mesh_queue_preq(struct mesh_path *mpath, u8 flags) 1000 { 1001 struct ieee80211_sub_if_data *sdata = mpath->sdata; 1002 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 1003 struct mesh_preq_queue *preq_node; 1004 1005 preq_node = kmalloc(sizeof(struct mesh_preq_queue), GFP_ATOMIC); 1006 if (!preq_node) { 1007 mhwmp_dbg(sdata, "could not allocate PREQ node\n"); 1008 return; 1009 } 1010 1011 spin_lock_bh(&ifmsh->mesh_preq_queue_lock); 1012 if (ifmsh->preq_queue_len == MAX_PREQ_QUEUE_LEN) { 1013 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock); 1014 kfree(preq_node); 1015 if (printk_ratelimit()) 1016 mhwmp_dbg(sdata, "PREQ node queue full\n"); 1017 return; 1018 } 1019 1020 spin_lock(&mpath->state_lock); 1021 if (mpath->flags & MESH_PATH_REQ_QUEUED) { 1022 spin_unlock(&mpath->state_lock); 1023 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock); 1024 kfree(preq_node); 1025 return; 1026 } 1027 1028 memcpy(preq_node->dst, mpath->dst, ETH_ALEN); 1029 preq_node->flags = flags; 1030 1031 mpath->flags |= MESH_PATH_REQ_QUEUED; 1032 spin_unlock(&mpath->state_lock); 1033 1034 list_add_tail(&preq_node->list, &ifmsh->preq_queue.list); 1035 ++ifmsh->preq_queue_len; 1036 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock); 1037 1038 if (time_after(jiffies, ifmsh->last_preq + min_preq_int_jiff(sdata))) 1039 wiphy_work_queue(sdata->local->hw.wiphy, &sdata->work); 1040 1041 else if (time_before(jiffies, ifmsh->last_preq)) { 1042 /* avoid long wait if did not send preqs for a long time 1043 * and jiffies wrapped around 1044 */ 1045 ifmsh->last_preq = jiffies - min_preq_int_jiff(sdata) - 1; 1046 wiphy_work_queue(sdata->local->hw.wiphy, &sdata->work); 1047 } else 1048 mod_timer(&ifmsh->mesh_path_timer, ifmsh->last_preq + 1049 min_preq_int_jiff(sdata)); 1050 } 1051 1052 /** 1053 * mesh_path_start_discovery - launch a path discovery from the PREQ queue 1054 * 1055 * @sdata: local mesh subif 1056 */ 1057 void mesh_path_start_discovery(struct ieee80211_sub_if_data *sdata) 1058 { 1059 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 1060 struct mesh_preq_queue *preq_node; 1061 struct mesh_path *mpath; 1062 u8 ttl, target_flags = 0; 1063 const u8 *da; 1064 u32 lifetime; 1065 1066 spin_lock_bh(&ifmsh->mesh_preq_queue_lock); 1067 if (!ifmsh->preq_queue_len || 1068 time_before(jiffies, ifmsh->last_preq + 1069 min_preq_int_jiff(sdata))) { 1070 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock); 1071 return; 1072 } 1073 1074 preq_node = list_first_entry(&ifmsh->preq_queue.list, 1075 struct mesh_preq_queue, list); 1076 list_del(&preq_node->list); 1077 --ifmsh->preq_queue_len; 1078 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock); 1079 1080 rcu_read_lock(); 1081 mpath = mesh_path_lookup(sdata, preq_node->dst); 1082 if (!mpath) 1083 goto enddiscovery; 1084 1085 spin_lock_bh(&mpath->state_lock); 1086 if (mpath->flags & (MESH_PATH_DELETED | MESH_PATH_FIXED)) { 1087 spin_unlock_bh(&mpath->state_lock); 1088 goto enddiscovery; 1089 } 1090 mpath->flags &= ~MESH_PATH_REQ_QUEUED; 1091 if (preq_node->flags & PREQ_Q_F_START) { 1092 if (mpath->flags & MESH_PATH_RESOLVING) { 1093 spin_unlock_bh(&mpath->state_lock); 1094 goto enddiscovery; 1095 } else { 1096 mpath->flags &= ~MESH_PATH_RESOLVED; 1097 mpath->flags |= MESH_PATH_RESOLVING; 1098 mpath->discovery_retries = 0; 1099 mpath->discovery_timeout = disc_timeout_jiff(sdata); 1100 } 1101 } else if (!(mpath->flags & MESH_PATH_RESOLVING) || 1102 mpath->flags & MESH_PATH_RESOLVED) { 1103 mpath->flags &= ~MESH_PATH_RESOLVING; 1104 spin_unlock_bh(&mpath->state_lock); 1105 goto enddiscovery; 1106 } 1107 1108 ifmsh->last_preq = jiffies; 1109 1110 if (time_after(jiffies, ifmsh->last_sn_update + 1111 net_traversal_jiffies(sdata)) || 1112 time_before(jiffies, ifmsh->last_sn_update)) { 1113 ++ifmsh->sn; 1114 sdata->u.mesh.last_sn_update = jiffies; 1115 } 1116 lifetime = default_lifetime(sdata); 1117 ttl = sdata->u.mesh.mshcfg.element_ttl; 1118 if (ttl == 0) { 1119 sdata->u.mesh.mshstats.dropped_frames_ttl++; 1120 spin_unlock_bh(&mpath->state_lock); 1121 goto enddiscovery; 1122 } 1123 1124 if (preq_node->flags & PREQ_Q_F_REFRESH) 1125 target_flags |= IEEE80211_PREQ_TO_FLAG; 1126 else 1127 target_flags &= ~IEEE80211_PREQ_TO_FLAG; 1128 1129 spin_unlock_bh(&mpath->state_lock); 1130 da = (mpath->is_root) ? mpath->rann_snd_addr : broadcast_addr; 1131 mesh_path_sel_frame_tx(MPATH_PREQ, 0, sdata->vif.addr, ifmsh->sn, 1132 target_flags, mpath->dst, mpath->sn, da, 0, 1133 ttl, lifetime, 0, ifmsh->preq_id++, sdata); 1134 1135 spin_lock_bh(&mpath->state_lock); 1136 if (!(mpath->flags & MESH_PATH_DELETED)) 1137 mod_timer(&mpath->timer, jiffies + mpath->discovery_timeout); 1138 spin_unlock_bh(&mpath->state_lock); 1139 1140 enddiscovery: 1141 rcu_read_unlock(); 1142 kfree(preq_node); 1143 } 1144 1145 /** 1146 * mesh_nexthop_resolve - lookup next hop; conditionally start path discovery 1147 * 1148 * @sdata: network subif the frame will be sent through 1149 * @skb: 802.11 frame to be sent 1150 * 1151 * Lookup next hop for given skb and start path discovery if no 1152 * forwarding information is found. 1153 * 1154 * Returns: 0 if the next hop was found and -ENOENT if the frame was queued. 1155 * skb is freed here if no mpath could be allocated. 1156 */ 1157 int mesh_nexthop_resolve(struct ieee80211_sub_if_data *sdata, 1158 struct sk_buff *skb) 1159 { 1160 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 1161 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 1162 struct mesh_path *mpath; 1163 struct sk_buff *skb_to_free = NULL; 1164 u8 *target_addr = hdr->addr3; 1165 1166 /* Nulls are only sent to peers for PS and should be pre-addressed */ 1167 if (ieee80211_is_qos_nullfunc(hdr->frame_control)) 1168 return 0; 1169 1170 /* Allow injected packets to bypass mesh routing */ 1171 if (info->control.flags & IEEE80211_TX_CTRL_SKIP_MPATH_LOOKUP) 1172 return 0; 1173 1174 if (!mesh_nexthop_lookup(sdata, skb)) 1175 return 0; 1176 1177 /* no nexthop found, start resolving */ 1178 mpath = mesh_path_lookup(sdata, target_addr); 1179 if (!mpath) { 1180 mpath = mesh_path_add(sdata, target_addr); 1181 if (IS_ERR(mpath)) { 1182 mesh_path_discard_frame(sdata, skb); 1183 return PTR_ERR(mpath); 1184 } 1185 } 1186 1187 if (!(mpath->flags & MESH_PATH_RESOLVING) && 1188 mesh_path_sel_is_hwmp(sdata)) 1189 mesh_queue_preq(mpath, PREQ_Q_F_START); 1190 1191 if (skb_queue_len(&mpath->frame_queue) >= MESH_FRAME_QUEUE_LEN) 1192 skb_to_free = skb_dequeue(&mpath->frame_queue); 1193 1194 info->control.flags |= IEEE80211_TX_INTCFL_NEED_TXPROCESSING; 1195 ieee80211_set_qos_hdr(sdata, skb); 1196 skb_queue_tail(&mpath->frame_queue, skb); 1197 if (skb_to_free) 1198 mesh_path_discard_frame(sdata, skb_to_free); 1199 1200 return -ENOENT; 1201 } 1202 1203 /** 1204 * mesh_nexthop_lookup_nolearn - try to set next hop without path discovery 1205 * @skb: 802.11 frame to be sent 1206 * @sdata: network subif the frame will be sent through 1207 * 1208 * Check if the meshDA (addr3) of a unicast frame is a direct neighbor. 1209 * And if so, set the RA (addr1) to it to transmit to this node directly, 1210 * avoiding PREQ/PREP path discovery. 1211 * 1212 * Returns: 0 if the next hop was found and -ENOENT otherwise. 1213 */ 1214 static int mesh_nexthop_lookup_nolearn(struct ieee80211_sub_if_data *sdata, 1215 struct sk_buff *skb) 1216 { 1217 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 1218 struct sta_info *sta; 1219 1220 if (is_multicast_ether_addr(hdr->addr1)) 1221 return -ENOENT; 1222 1223 rcu_read_lock(); 1224 sta = sta_info_get(sdata, hdr->addr3); 1225 1226 if (!sta || sta->mesh->plink_state != NL80211_PLINK_ESTAB) { 1227 rcu_read_unlock(); 1228 return -ENOENT; 1229 } 1230 rcu_read_unlock(); 1231 1232 memcpy(hdr->addr1, hdr->addr3, ETH_ALEN); 1233 memcpy(hdr->addr2, sdata->vif.addr, ETH_ALEN); 1234 return 0; 1235 } 1236 1237 void mesh_path_refresh(struct ieee80211_sub_if_data *sdata, 1238 struct mesh_path *mpath, const u8 *addr) 1239 { 1240 if (mpath->flags & (MESH_PATH_REQ_QUEUED | MESH_PATH_FIXED | 1241 MESH_PATH_RESOLVING)) 1242 return; 1243 1244 if (time_after(jiffies, 1245 mpath->exp_time - 1246 msecs_to_jiffies(sdata->u.mesh.mshcfg.path_refresh_time)) && 1247 (!addr || ether_addr_equal(sdata->vif.addr, addr))) 1248 mesh_queue_preq(mpath, PREQ_Q_F_START | PREQ_Q_F_REFRESH); 1249 } 1250 1251 /** 1252 * mesh_nexthop_lookup - put the appropriate next hop on a mesh frame. Calling 1253 * this function is considered "using" the associated mpath, so preempt a path 1254 * refresh if this mpath expires soon. 1255 * 1256 * @sdata: network subif the frame will be sent through 1257 * @skb: 802.11 frame to be sent 1258 * 1259 * Returns: 0 if the next hop was found. Nonzero otherwise. 1260 */ 1261 int mesh_nexthop_lookup(struct ieee80211_sub_if_data *sdata, 1262 struct sk_buff *skb) 1263 { 1264 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 1265 struct mesh_path *mpath; 1266 struct sta_info *next_hop; 1267 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 1268 u8 *target_addr = hdr->addr3; 1269 1270 if (ifmsh->mshcfg.dot11MeshNolearn && 1271 !mesh_nexthop_lookup_nolearn(sdata, skb)) 1272 return 0; 1273 1274 mpath = mesh_path_lookup(sdata, target_addr); 1275 if (!mpath || !(mpath->flags & MESH_PATH_ACTIVE)) 1276 return -ENOENT; 1277 1278 mesh_path_refresh(sdata, mpath, hdr->addr4); 1279 1280 next_hop = rcu_dereference(mpath->next_hop); 1281 if (next_hop) { 1282 memcpy(hdr->addr1, next_hop->sta.addr, ETH_ALEN); 1283 memcpy(hdr->addr2, sdata->vif.addr, ETH_ALEN); 1284 ieee80211_mps_set_frame_flags(sdata, next_hop, hdr); 1285 if (ieee80211_hw_check(&sdata->local->hw, SUPPORT_FAST_XMIT)) 1286 mesh_fast_tx_cache(sdata, skb, mpath); 1287 return 0; 1288 } 1289 1290 return -ENOENT; 1291 } 1292 1293 void mesh_path_timer(struct timer_list *t) 1294 { 1295 struct mesh_path *mpath = timer_container_of(mpath, t, timer); 1296 struct ieee80211_sub_if_data *sdata = mpath->sdata; 1297 int ret; 1298 1299 if (sdata->local->quiescing) 1300 return; 1301 1302 spin_lock_bh(&mpath->state_lock); 1303 if (mpath->flags & MESH_PATH_RESOLVED || 1304 (!(mpath->flags & MESH_PATH_RESOLVING))) { 1305 mpath->flags &= ~(MESH_PATH_RESOLVING | MESH_PATH_RESOLVED); 1306 spin_unlock_bh(&mpath->state_lock); 1307 } else if (mpath->discovery_retries < max_preq_retries(sdata)) { 1308 ++mpath->discovery_retries; 1309 mpath->discovery_timeout *= 2; 1310 mpath->flags &= ~MESH_PATH_REQ_QUEUED; 1311 spin_unlock_bh(&mpath->state_lock); 1312 mesh_queue_preq(mpath, 0); 1313 } else { 1314 mpath->flags &= ~(MESH_PATH_RESOLVING | 1315 MESH_PATH_RESOLVED | 1316 MESH_PATH_REQ_QUEUED); 1317 mpath->exp_time = jiffies; 1318 spin_unlock_bh(&mpath->state_lock); 1319 if (!mpath->is_gate && mesh_gate_num(sdata) > 0) { 1320 ret = mesh_path_send_to_gates(mpath); 1321 if (ret) 1322 mhwmp_dbg(sdata, "no gate was reachable\n"); 1323 } else 1324 mesh_path_flush_pending(mpath); 1325 } 1326 } 1327 1328 void mesh_path_tx_root_frame(struct ieee80211_sub_if_data *sdata) 1329 { 1330 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 1331 u32 interval = ifmsh->mshcfg.dot11MeshHWMPRannInterval; 1332 u8 flags, target_flags = 0; 1333 1334 flags = (ifmsh->mshcfg.dot11MeshGateAnnouncementProtocol) 1335 ? RANN_FLAG_IS_GATE : 0; 1336 1337 switch (ifmsh->mshcfg.dot11MeshHWMPRootMode) { 1338 case IEEE80211_PROACTIVE_RANN: 1339 mesh_path_sel_frame_tx(MPATH_RANN, flags, sdata->vif.addr, 1340 ++ifmsh->sn, 0, NULL, 0, broadcast_addr, 1341 0, ifmsh->mshcfg.element_ttl, 1342 interval, 0, 0, sdata); 1343 break; 1344 case IEEE80211_PROACTIVE_PREQ_WITH_PREP: 1345 flags |= IEEE80211_PREQ_PROACTIVE_PREP_FLAG; 1346 fallthrough; 1347 case IEEE80211_PROACTIVE_PREQ_NO_PREP: 1348 interval = ifmsh->mshcfg.dot11MeshHWMPactivePathToRootTimeout; 1349 target_flags |= IEEE80211_PREQ_TO_FLAG | 1350 IEEE80211_PREQ_USN_FLAG; 1351 mesh_path_sel_frame_tx(MPATH_PREQ, flags, sdata->vif.addr, 1352 ++ifmsh->sn, target_flags, 1353 (u8 *) broadcast_addr, 0, broadcast_addr, 1354 0, ifmsh->mshcfg.element_ttl, interval, 1355 0, ifmsh->preq_id++, sdata); 1356 break; 1357 default: 1358 mhwmp_dbg(sdata, "Proactive mechanism not supported\n"); 1359 return; 1360 } 1361 } 1362