1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (c) 2008, 2009 open80211s Ltd. 4 * Copyright (C) 2019, 2021-2022 Intel Corporation 5 * Author: Luis Carlos Cobo <luisca@cozybit.com> 6 */ 7 8 #include <linux/slab.h> 9 #include <linux/etherdevice.h> 10 #include <asm/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 -ENOTSUPP; 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 * @ttl: allowed remaining hops 224 * @target: broken destination 225 * @target_sn: SN of the broken destination 226 * @target_rcode: reason code for this PERR 227 * @ra: node this frame is addressed to 228 * @sdata: local mesh subif 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 int mesh_path_error_tx(struct ieee80211_sub_if_data *sdata, 235 u8 ttl, const u8 *target, u32 target_sn, 236 u16 target_rcode, const u8 *ra) 237 { 238 struct ieee80211_local *local = sdata->local; 239 struct sk_buff *skb; 240 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 241 struct ieee80211_mgmt *mgmt; 242 u8 *pos, ie_len; 243 int hdr_len = offsetofend(struct ieee80211_mgmt, 244 u.action.u.mesh_action); 245 246 if (time_before(jiffies, ifmsh->next_perr)) 247 return -EAGAIN; 248 249 skb = dev_alloc_skb(local->tx_headroom + 250 IEEE80211_ENCRYPT_HEADROOM + 251 IEEE80211_ENCRYPT_TAILROOM + 252 hdr_len + 253 2 + 15 /* PERR IE */); 254 if (!skb) 255 return -1; 256 skb_reserve(skb, local->tx_headroom + IEEE80211_ENCRYPT_HEADROOM); 257 mgmt = skb_put_zero(skb, hdr_len); 258 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 259 IEEE80211_STYPE_ACTION); 260 261 memcpy(mgmt->da, ra, ETH_ALEN); 262 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN); 263 /* BSSID == SA */ 264 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN); 265 mgmt->u.action.category = WLAN_CATEGORY_MESH_ACTION; 266 mgmt->u.action.u.mesh_action.action_code = 267 WLAN_MESH_ACTION_HWMP_PATH_SELECTION; 268 ie_len = 15; 269 pos = skb_put(skb, 2 + ie_len); 270 *pos++ = WLAN_EID_PERR; 271 *pos++ = ie_len; 272 /* ttl */ 273 *pos++ = ttl; 274 /* number of destinations */ 275 *pos++ = 1; 276 /* Flags field has AE bit only as defined in 277 * sec 8.4.2.117 IEEE802.11-2012 278 */ 279 *pos = 0; 280 pos++; 281 memcpy(pos, target, ETH_ALEN); 282 pos += ETH_ALEN; 283 put_unaligned_le32(target_sn, pos); 284 pos += 4; 285 put_unaligned_le16(target_rcode, pos); 286 287 /* see note in function header */ 288 prepare_frame_for_deferred_tx(sdata, skb); 289 ifmsh->next_perr = TU_TO_EXP_TIME( 290 ifmsh->mshcfg.dot11MeshHWMPperrMinInterval); 291 ieee80211_add_pending_skb(local, skb); 292 return 0; 293 } 294 295 void ieee80211s_update_metric(struct ieee80211_local *local, 296 struct sta_info *sta, 297 struct ieee80211_tx_status *st) 298 { 299 struct ieee80211_tx_info *txinfo = st->info; 300 int failed; 301 struct rate_info rinfo; 302 303 failed = !(txinfo->flags & IEEE80211_TX_STAT_ACK); 304 305 /* moving average, scaled to 100. 306 * feed failure as 100 and success as 0 307 */ 308 ewma_mesh_fail_avg_add(&sta->mesh->fail_avg, failed * 100); 309 if (ewma_mesh_fail_avg_read(&sta->mesh->fail_avg) > 310 LINK_FAIL_THRESH) 311 mesh_plink_broken(sta); 312 313 /* use rate info set by the driver directly if present */ 314 if (st->n_rates) 315 rinfo = sta->deflink.tx_stats.last_rate_info; 316 else 317 sta_set_rate_info_tx(sta, &sta->deflink.tx_stats.last_rate, &rinfo); 318 319 ewma_mesh_tx_rate_avg_add(&sta->mesh->tx_rate_avg, 320 cfg80211_calculate_bitrate(&rinfo)); 321 } 322 323 u32 airtime_link_metric_get(struct ieee80211_local *local, 324 struct sta_info *sta) 325 { 326 /* This should be adjusted for each device */ 327 int device_constant = 1 << ARITH_SHIFT; 328 int test_frame_len = TEST_FRAME_LEN << ARITH_SHIFT; 329 int s_unit = 1 << ARITH_SHIFT; 330 int rate, err; 331 u32 tx_time, estimated_retx; 332 u64 result; 333 unsigned long fail_avg = 334 ewma_mesh_fail_avg_read(&sta->mesh->fail_avg); 335 336 if (sta->mesh->plink_state != NL80211_PLINK_ESTAB) 337 return MAX_METRIC; 338 339 /* Try to get rate based on HW/SW RC algorithm. 340 * Rate is returned in units of Kbps, correct this 341 * to comply with airtime calculation units 342 * Round up in case we get rate < 100Kbps 343 */ 344 rate = DIV_ROUND_UP(sta_get_expected_throughput(sta), 100); 345 346 if (rate) { 347 err = 0; 348 } else { 349 if (fail_avg > LINK_FAIL_THRESH) 350 return MAX_METRIC; 351 352 rate = ewma_mesh_tx_rate_avg_read(&sta->mesh->tx_rate_avg); 353 if (WARN_ON(!rate)) 354 return MAX_METRIC; 355 356 err = (fail_avg << ARITH_SHIFT) / 100; 357 } 358 359 /* bitrate is in units of 100 Kbps, while we need rate in units of 360 * 1Mbps. This will be corrected on tx_time computation. 361 */ 362 tx_time = (device_constant + 10 * test_frame_len / rate); 363 estimated_retx = ((1 << (2 * ARITH_SHIFT)) / (s_unit - err)); 364 result = ((u64)tx_time * estimated_retx) >> (2 * ARITH_SHIFT); 365 return (u32)result; 366 } 367 368 /** 369 * hwmp_route_info_get - Update routing info to originator and transmitter 370 * 371 * @sdata: local mesh subif 372 * @mgmt: mesh management frame 373 * @hwmp_ie: hwmp information element (PREP or PREQ) 374 * @action: type of hwmp ie 375 * 376 * This function updates the path routing information to the originator and the 377 * transmitter of a HWMP PREQ or PREP frame. 378 * 379 * Returns: metric to frame originator or 0 if the frame should not be further 380 * processed 381 * 382 * Notes: this function is the only place (besides user-provided info) where 383 * path routing information is updated. 384 */ 385 static u32 hwmp_route_info_get(struct ieee80211_sub_if_data *sdata, 386 struct ieee80211_mgmt *mgmt, 387 const u8 *hwmp_ie, enum mpath_frame_type action) 388 { 389 struct ieee80211_local *local = sdata->local; 390 struct mesh_path *mpath; 391 struct sta_info *sta; 392 bool fresh_info; 393 const u8 *orig_addr, *ta; 394 u32 orig_sn, orig_metric; 395 unsigned long orig_lifetime, exp_time; 396 u32 last_hop_metric, new_metric; 397 bool process = true; 398 u8 hopcount; 399 400 rcu_read_lock(); 401 sta = sta_info_get(sdata, mgmt->sa); 402 if (!sta) { 403 rcu_read_unlock(); 404 return 0; 405 } 406 407 last_hop_metric = airtime_link_metric_get(local, sta); 408 /* Update and check originator routing info */ 409 fresh_info = true; 410 411 switch (action) { 412 case MPATH_PREQ: 413 orig_addr = PREQ_IE_ORIG_ADDR(hwmp_ie); 414 orig_sn = PREQ_IE_ORIG_SN(hwmp_ie); 415 orig_lifetime = PREQ_IE_LIFETIME(hwmp_ie); 416 orig_metric = PREQ_IE_METRIC(hwmp_ie); 417 hopcount = PREQ_IE_HOPCOUNT(hwmp_ie) + 1; 418 break; 419 case MPATH_PREP: 420 /* Originator here refers to the MP that was the target in the 421 * Path Request. We divert from the nomenclature in the draft 422 * so that we can easily use a single function to gather path 423 * information from both PREQ and PREP frames. 424 */ 425 orig_addr = PREP_IE_TARGET_ADDR(hwmp_ie); 426 orig_sn = PREP_IE_TARGET_SN(hwmp_ie); 427 orig_lifetime = PREP_IE_LIFETIME(hwmp_ie); 428 orig_metric = PREP_IE_METRIC(hwmp_ie); 429 hopcount = PREP_IE_HOPCOUNT(hwmp_ie) + 1; 430 break; 431 default: 432 rcu_read_unlock(); 433 return 0; 434 } 435 new_metric = orig_metric + last_hop_metric; 436 if (new_metric < orig_metric) 437 new_metric = MAX_METRIC; 438 exp_time = TU_TO_EXP_TIME(orig_lifetime); 439 440 if (ether_addr_equal(orig_addr, sdata->vif.addr)) { 441 /* This MP is the originator, we are not interested in this 442 * frame, except for updating transmitter's path info. 443 */ 444 process = false; 445 fresh_info = false; 446 } else { 447 mpath = mesh_path_lookup(sdata, orig_addr); 448 if (mpath) { 449 spin_lock_bh(&mpath->state_lock); 450 if (mpath->flags & MESH_PATH_FIXED) 451 fresh_info = false; 452 else if ((mpath->flags & MESH_PATH_ACTIVE) && 453 (mpath->flags & MESH_PATH_SN_VALID)) { 454 if (SN_GT(mpath->sn, orig_sn) || 455 (mpath->sn == orig_sn && 456 (rcu_access_pointer(mpath->next_hop) != 457 sta ? 458 mult_frac(new_metric, 10, 9) : 459 new_metric) >= mpath->metric)) { 460 process = false; 461 fresh_info = false; 462 } 463 } else if (!(mpath->flags & MESH_PATH_ACTIVE)) { 464 bool have_sn, newer_sn, bounced; 465 466 have_sn = mpath->flags & MESH_PATH_SN_VALID; 467 newer_sn = have_sn && SN_GT(orig_sn, mpath->sn); 468 bounced = have_sn && 469 (SN_DELTA(orig_sn, mpath->sn) > 470 MAX_SANE_SN_DELTA); 471 472 if (!have_sn || newer_sn) { 473 /* if SN is newer than what we had 474 * then we can take it */; 475 } else if (bounced) { 476 /* if SN is way different than what 477 * we had then assume the other side 478 * rebooted or restarted */; 479 } else { 480 process = false; 481 fresh_info = false; 482 } 483 } 484 } else { 485 mpath = mesh_path_add(sdata, orig_addr); 486 if (IS_ERR(mpath)) { 487 rcu_read_unlock(); 488 return 0; 489 } 490 spin_lock_bh(&mpath->state_lock); 491 } 492 493 if (fresh_info) { 494 if (rcu_access_pointer(mpath->next_hop) != sta) 495 mpath->path_change_count++; 496 mesh_path_assign_nexthop(mpath, sta); 497 mpath->flags |= MESH_PATH_SN_VALID; 498 mpath->metric = new_metric; 499 mpath->sn = orig_sn; 500 mpath->exp_time = time_after(mpath->exp_time, exp_time) 501 ? mpath->exp_time : exp_time; 502 mpath->hop_count = hopcount; 503 mesh_path_activate(mpath); 504 spin_unlock_bh(&mpath->state_lock); 505 ewma_mesh_fail_avg_init(&sta->mesh->fail_avg); 506 /* init it at a low value - 0 start is tricky */ 507 ewma_mesh_fail_avg_add(&sta->mesh->fail_avg, 1); 508 mesh_path_tx_pending(mpath); 509 /* draft says preq_id should be saved to, but there does 510 * not seem to be any use for it, skipping by now 511 */ 512 } else 513 spin_unlock_bh(&mpath->state_lock); 514 } 515 516 /* Update and check transmitter routing info */ 517 ta = mgmt->sa; 518 if (ether_addr_equal(orig_addr, ta)) 519 fresh_info = false; 520 else { 521 fresh_info = true; 522 523 mpath = mesh_path_lookup(sdata, ta); 524 if (mpath) { 525 spin_lock_bh(&mpath->state_lock); 526 if ((mpath->flags & MESH_PATH_FIXED) || 527 ((mpath->flags & MESH_PATH_ACTIVE) && 528 ((rcu_access_pointer(mpath->next_hop) != sta ? 529 mult_frac(last_hop_metric, 10, 9) : 530 last_hop_metric) > mpath->metric))) 531 fresh_info = false; 532 } else { 533 mpath = mesh_path_add(sdata, ta); 534 if (IS_ERR(mpath)) { 535 rcu_read_unlock(); 536 return 0; 537 } 538 spin_lock_bh(&mpath->state_lock); 539 } 540 541 if (fresh_info) { 542 if (rcu_access_pointer(mpath->next_hop) != sta) 543 mpath->path_change_count++; 544 mesh_path_assign_nexthop(mpath, sta); 545 mpath->metric = last_hop_metric; 546 mpath->exp_time = time_after(mpath->exp_time, exp_time) 547 ? mpath->exp_time : exp_time; 548 mpath->hop_count = 1; 549 mesh_path_activate(mpath); 550 spin_unlock_bh(&mpath->state_lock); 551 ewma_mesh_fail_avg_init(&sta->mesh->fail_avg); 552 /* init it at a low value - 0 start is tricky */ 553 ewma_mesh_fail_avg_add(&sta->mesh->fail_avg, 1); 554 mesh_path_tx_pending(mpath); 555 } else 556 spin_unlock_bh(&mpath->state_lock); 557 } 558 559 rcu_read_unlock(); 560 561 return process ? new_metric : 0; 562 } 563 564 static void hwmp_preq_frame_process(struct ieee80211_sub_if_data *sdata, 565 struct ieee80211_mgmt *mgmt, 566 const u8 *preq_elem, u32 orig_metric) 567 { 568 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 569 struct mesh_path *mpath = NULL; 570 const u8 *target_addr, *orig_addr; 571 const u8 *da; 572 u8 target_flags, ttl, flags; 573 u32 orig_sn, target_sn, lifetime, target_metric = 0; 574 bool reply = false; 575 bool forward = true; 576 bool root_is_gate; 577 578 /* Update target SN, if present */ 579 target_addr = PREQ_IE_TARGET_ADDR(preq_elem); 580 orig_addr = PREQ_IE_ORIG_ADDR(preq_elem); 581 target_sn = PREQ_IE_TARGET_SN(preq_elem); 582 orig_sn = PREQ_IE_ORIG_SN(preq_elem); 583 target_flags = PREQ_IE_TARGET_F(preq_elem); 584 /* Proactive PREQ gate announcements */ 585 flags = PREQ_IE_FLAGS(preq_elem); 586 root_is_gate = !!(flags & RANN_FLAG_IS_GATE); 587 588 mhwmp_dbg(sdata, "received PREQ from %pM\n", orig_addr); 589 590 if (ether_addr_equal(target_addr, sdata->vif.addr)) { 591 mhwmp_dbg(sdata, "PREQ is for us\n"); 592 forward = false; 593 reply = true; 594 target_metric = 0; 595 596 if (SN_GT(target_sn, ifmsh->sn)) 597 ifmsh->sn = target_sn; 598 599 if (time_after(jiffies, ifmsh->last_sn_update + 600 net_traversal_jiffies(sdata)) || 601 time_before(jiffies, ifmsh->last_sn_update)) { 602 ++ifmsh->sn; 603 ifmsh->last_sn_update = jiffies; 604 } 605 target_sn = ifmsh->sn; 606 } else if (is_broadcast_ether_addr(target_addr) && 607 (target_flags & IEEE80211_PREQ_TO_FLAG)) { 608 rcu_read_lock(); 609 mpath = mesh_path_lookup(sdata, orig_addr); 610 if (mpath) { 611 if (flags & IEEE80211_PREQ_PROACTIVE_PREP_FLAG) { 612 reply = true; 613 target_addr = sdata->vif.addr; 614 target_sn = ++ifmsh->sn; 615 target_metric = 0; 616 ifmsh->last_sn_update = jiffies; 617 } 618 if (root_is_gate) 619 mesh_path_add_gate(mpath); 620 } 621 rcu_read_unlock(); 622 } else { 623 rcu_read_lock(); 624 mpath = mesh_path_lookup(sdata, target_addr); 625 if (mpath) { 626 if ((!(mpath->flags & MESH_PATH_SN_VALID)) || 627 SN_LT(mpath->sn, target_sn)) { 628 mpath->sn = target_sn; 629 mpath->flags |= MESH_PATH_SN_VALID; 630 } else if ((!(target_flags & IEEE80211_PREQ_TO_FLAG)) && 631 (mpath->flags & MESH_PATH_ACTIVE)) { 632 reply = true; 633 target_metric = mpath->metric; 634 target_sn = mpath->sn; 635 /* Case E2 of sec 13.10.9.3 IEEE 802.11-2012*/ 636 target_flags |= IEEE80211_PREQ_TO_FLAG; 637 } 638 } 639 rcu_read_unlock(); 640 } 641 642 if (reply) { 643 lifetime = PREQ_IE_LIFETIME(preq_elem); 644 ttl = ifmsh->mshcfg.element_ttl; 645 if (ttl != 0) { 646 mhwmp_dbg(sdata, "replying to the PREQ\n"); 647 mesh_path_sel_frame_tx(MPATH_PREP, 0, orig_addr, 648 orig_sn, 0, target_addr, 649 target_sn, mgmt->sa, 0, ttl, 650 lifetime, target_metric, 0, 651 sdata); 652 } else { 653 ifmsh->mshstats.dropped_frames_ttl++; 654 } 655 } 656 657 if (forward && ifmsh->mshcfg.dot11MeshForwarding) { 658 u32 preq_id; 659 u8 hopcount; 660 661 ttl = PREQ_IE_TTL(preq_elem); 662 lifetime = PREQ_IE_LIFETIME(preq_elem); 663 if (ttl <= 1) { 664 ifmsh->mshstats.dropped_frames_ttl++; 665 return; 666 } 667 mhwmp_dbg(sdata, "forwarding the PREQ from %pM\n", orig_addr); 668 --ttl; 669 preq_id = PREQ_IE_PREQ_ID(preq_elem); 670 hopcount = PREQ_IE_HOPCOUNT(preq_elem) + 1; 671 da = (mpath && mpath->is_root) ? 672 mpath->rann_snd_addr : broadcast_addr; 673 674 if (flags & IEEE80211_PREQ_PROACTIVE_PREP_FLAG) { 675 target_addr = PREQ_IE_TARGET_ADDR(preq_elem); 676 target_sn = PREQ_IE_TARGET_SN(preq_elem); 677 } 678 679 mesh_path_sel_frame_tx(MPATH_PREQ, flags, orig_addr, 680 orig_sn, target_flags, target_addr, 681 target_sn, da, hopcount, ttl, lifetime, 682 orig_metric, preq_id, sdata); 683 if (!is_multicast_ether_addr(da)) 684 ifmsh->mshstats.fwded_unicast++; 685 else 686 ifmsh->mshstats.fwded_mcast++; 687 ifmsh->mshstats.fwded_frames++; 688 } 689 } 690 691 692 static inline struct sta_info * 693 next_hop_deref_protected(struct mesh_path *mpath) 694 { 695 return rcu_dereference_protected(mpath->next_hop, 696 lockdep_is_held(&mpath->state_lock)); 697 } 698 699 700 static void hwmp_prep_frame_process(struct ieee80211_sub_if_data *sdata, 701 struct ieee80211_mgmt *mgmt, 702 const u8 *prep_elem, u32 metric) 703 { 704 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 705 struct mesh_path *mpath; 706 const u8 *target_addr, *orig_addr; 707 u8 ttl, hopcount, flags; 708 u8 next_hop[ETH_ALEN]; 709 u32 target_sn, orig_sn, lifetime; 710 711 mhwmp_dbg(sdata, "received PREP from %pM\n", 712 PREP_IE_TARGET_ADDR(prep_elem)); 713 714 orig_addr = PREP_IE_ORIG_ADDR(prep_elem); 715 if (ether_addr_equal(orig_addr, sdata->vif.addr)) 716 /* destination, no forwarding required */ 717 return; 718 719 if (!ifmsh->mshcfg.dot11MeshForwarding) 720 return; 721 722 ttl = PREP_IE_TTL(prep_elem); 723 if (ttl <= 1) { 724 sdata->u.mesh.mshstats.dropped_frames_ttl++; 725 return; 726 } 727 728 rcu_read_lock(); 729 mpath = mesh_path_lookup(sdata, orig_addr); 730 if (mpath) 731 spin_lock_bh(&mpath->state_lock); 732 else 733 goto fail; 734 if (!(mpath->flags & MESH_PATH_ACTIVE)) { 735 spin_unlock_bh(&mpath->state_lock); 736 goto fail; 737 } 738 memcpy(next_hop, next_hop_deref_protected(mpath)->sta.addr, ETH_ALEN); 739 spin_unlock_bh(&mpath->state_lock); 740 --ttl; 741 flags = PREP_IE_FLAGS(prep_elem); 742 lifetime = PREP_IE_LIFETIME(prep_elem); 743 hopcount = PREP_IE_HOPCOUNT(prep_elem) + 1; 744 target_addr = PREP_IE_TARGET_ADDR(prep_elem); 745 target_sn = PREP_IE_TARGET_SN(prep_elem); 746 orig_sn = PREP_IE_ORIG_SN(prep_elem); 747 748 mesh_path_sel_frame_tx(MPATH_PREP, flags, orig_addr, orig_sn, 0, 749 target_addr, target_sn, next_hop, hopcount, 750 ttl, lifetime, metric, 0, sdata); 751 rcu_read_unlock(); 752 753 sdata->u.mesh.mshstats.fwded_unicast++; 754 sdata->u.mesh.mshstats.fwded_frames++; 755 return; 756 757 fail: 758 rcu_read_unlock(); 759 sdata->u.mesh.mshstats.dropped_frames_no_route++; 760 } 761 762 static void hwmp_perr_frame_process(struct ieee80211_sub_if_data *sdata, 763 struct ieee80211_mgmt *mgmt, 764 const u8 *perr_elem) 765 { 766 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 767 struct mesh_path *mpath; 768 u8 ttl; 769 const u8 *ta, *target_addr; 770 u32 target_sn; 771 u16 target_rcode; 772 773 ta = mgmt->sa; 774 ttl = PERR_IE_TTL(perr_elem); 775 if (ttl <= 1) { 776 ifmsh->mshstats.dropped_frames_ttl++; 777 return; 778 } 779 ttl--; 780 target_addr = PERR_IE_TARGET_ADDR(perr_elem); 781 target_sn = PERR_IE_TARGET_SN(perr_elem); 782 target_rcode = PERR_IE_TARGET_RCODE(perr_elem); 783 784 rcu_read_lock(); 785 mpath = mesh_path_lookup(sdata, target_addr); 786 if (mpath) { 787 struct sta_info *sta; 788 789 spin_lock_bh(&mpath->state_lock); 790 sta = next_hop_deref_protected(mpath); 791 if (mpath->flags & MESH_PATH_ACTIVE && 792 ether_addr_equal(ta, sta->sta.addr) && 793 !(mpath->flags & MESH_PATH_FIXED) && 794 (!(mpath->flags & MESH_PATH_SN_VALID) || 795 SN_GT(target_sn, mpath->sn) || target_sn == 0)) { 796 mpath->flags &= ~MESH_PATH_ACTIVE; 797 if (target_sn != 0) 798 mpath->sn = target_sn; 799 else 800 mpath->sn += 1; 801 spin_unlock_bh(&mpath->state_lock); 802 if (!ifmsh->mshcfg.dot11MeshForwarding) 803 goto endperr; 804 mesh_path_error_tx(sdata, ttl, target_addr, 805 target_sn, target_rcode, 806 broadcast_addr); 807 } else 808 spin_unlock_bh(&mpath->state_lock); 809 } 810 endperr: 811 rcu_read_unlock(); 812 } 813 814 static void hwmp_rann_frame_process(struct ieee80211_sub_if_data *sdata, 815 struct ieee80211_mgmt *mgmt, 816 const struct ieee80211_rann_ie *rann) 817 { 818 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 819 struct ieee80211_local *local = sdata->local; 820 struct sta_info *sta; 821 struct mesh_path *mpath; 822 u8 ttl, flags, hopcount; 823 const u8 *orig_addr; 824 u32 orig_sn, new_metric, orig_metric, last_hop_metric, interval; 825 bool root_is_gate; 826 827 ttl = rann->rann_ttl; 828 flags = rann->rann_flags; 829 root_is_gate = !!(flags & RANN_FLAG_IS_GATE); 830 orig_addr = rann->rann_addr; 831 orig_sn = le32_to_cpu(rann->rann_seq); 832 interval = le32_to_cpu(rann->rann_interval); 833 hopcount = rann->rann_hopcount; 834 hopcount++; 835 orig_metric = le32_to_cpu(rann->rann_metric); 836 837 /* Ignore our own RANNs */ 838 if (ether_addr_equal(orig_addr, sdata->vif.addr)) 839 return; 840 841 mhwmp_dbg(sdata, 842 "received RANN from %pM via neighbour %pM (is_gate=%d)\n", 843 orig_addr, mgmt->sa, root_is_gate); 844 845 rcu_read_lock(); 846 sta = sta_info_get(sdata, mgmt->sa); 847 if (!sta) { 848 rcu_read_unlock(); 849 return; 850 } 851 852 last_hop_metric = airtime_link_metric_get(local, sta); 853 new_metric = orig_metric + last_hop_metric; 854 if (new_metric < orig_metric) 855 new_metric = MAX_METRIC; 856 857 mpath = mesh_path_lookup(sdata, orig_addr); 858 if (!mpath) { 859 mpath = mesh_path_add(sdata, orig_addr); 860 if (IS_ERR(mpath)) { 861 rcu_read_unlock(); 862 sdata->u.mesh.mshstats.dropped_frames_no_route++; 863 return; 864 } 865 } 866 867 if (!(SN_LT(mpath->sn, orig_sn)) && 868 !(mpath->sn == orig_sn && new_metric < mpath->rann_metric)) { 869 rcu_read_unlock(); 870 return; 871 } 872 873 if ((!(mpath->flags & (MESH_PATH_ACTIVE | MESH_PATH_RESOLVING)) || 874 (time_after(jiffies, mpath->last_preq_to_root + 875 root_path_confirmation_jiffies(sdata)) || 876 time_before(jiffies, mpath->last_preq_to_root))) && 877 !(mpath->flags & MESH_PATH_FIXED) && (ttl != 0)) { 878 mhwmp_dbg(sdata, 879 "time to refresh root mpath %pM\n", 880 orig_addr); 881 mesh_queue_preq(mpath, PREQ_Q_F_START | PREQ_Q_F_REFRESH); 882 mpath->last_preq_to_root = jiffies; 883 } 884 885 mpath->sn = orig_sn; 886 mpath->rann_metric = new_metric; 887 mpath->is_root = true; 888 /* Recording RANNs sender address to send individually 889 * addressed PREQs destined for root mesh STA */ 890 memcpy(mpath->rann_snd_addr, mgmt->sa, ETH_ALEN); 891 892 if (root_is_gate) 893 mesh_path_add_gate(mpath); 894 895 if (ttl <= 1) { 896 ifmsh->mshstats.dropped_frames_ttl++; 897 rcu_read_unlock(); 898 return; 899 } 900 ttl--; 901 902 if (ifmsh->mshcfg.dot11MeshForwarding) { 903 mesh_path_sel_frame_tx(MPATH_RANN, flags, orig_addr, 904 orig_sn, 0, NULL, 0, broadcast_addr, 905 hopcount, ttl, interval, 906 new_metric, 0, sdata); 907 } 908 909 rcu_read_unlock(); 910 } 911 912 913 void mesh_rx_path_sel_frame(struct ieee80211_sub_if_data *sdata, 914 struct ieee80211_mgmt *mgmt, size_t len) 915 { 916 struct ieee802_11_elems *elems; 917 size_t baselen; 918 u32 path_metric; 919 struct sta_info *sta; 920 921 /* need action_code */ 922 if (len < IEEE80211_MIN_ACTION_SIZE + 1) 923 return; 924 925 rcu_read_lock(); 926 sta = sta_info_get(sdata, mgmt->sa); 927 if (!sta || sta->mesh->plink_state != NL80211_PLINK_ESTAB) { 928 rcu_read_unlock(); 929 return; 930 } 931 rcu_read_unlock(); 932 933 baselen = (u8 *) mgmt->u.action.u.mesh_action.variable - (u8 *) mgmt; 934 elems = ieee802_11_parse_elems(mgmt->u.action.u.mesh_action.variable, 935 len - baselen, false, NULL); 936 if (!elems) 937 return; 938 939 if (elems->preq) { 940 if (elems->preq_len != 37) 941 /* Right now we support just 1 destination and no AE */ 942 goto free; 943 path_metric = hwmp_route_info_get(sdata, mgmt, elems->preq, 944 MPATH_PREQ); 945 if (path_metric) 946 hwmp_preq_frame_process(sdata, mgmt, elems->preq, 947 path_metric); 948 } 949 if (elems->prep) { 950 if (elems->prep_len != 31) 951 /* Right now we support no AE */ 952 goto free; 953 path_metric = hwmp_route_info_get(sdata, mgmt, elems->prep, 954 MPATH_PREP); 955 if (path_metric) 956 hwmp_prep_frame_process(sdata, mgmt, elems->prep, 957 path_metric); 958 } 959 if (elems->perr) { 960 if (elems->perr_len != 15) 961 /* Right now we support only one destination per PERR */ 962 goto free; 963 hwmp_perr_frame_process(sdata, mgmt, elems->perr); 964 } 965 if (elems->rann) 966 hwmp_rann_frame_process(sdata, mgmt, elems->rann); 967 free: 968 kfree(elems); 969 } 970 971 /** 972 * mesh_queue_preq - queue a PREQ to a given destination 973 * 974 * @mpath: mesh path to discover 975 * @flags: special attributes of the PREQ to be sent 976 * 977 * Locking: the function must be called from within a rcu read lock block. 978 * 979 */ 980 static void mesh_queue_preq(struct mesh_path *mpath, u8 flags) 981 { 982 struct ieee80211_sub_if_data *sdata = mpath->sdata; 983 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 984 struct mesh_preq_queue *preq_node; 985 986 preq_node = kmalloc(sizeof(struct mesh_preq_queue), GFP_ATOMIC); 987 if (!preq_node) { 988 mhwmp_dbg(sdata, "could not allocate PREQ node\n"); 989 return; 990 } 991 992 spin_lock_bh(&ifmsh->mesh_preq_queue_lock); 993 if (ifmsh->preq_queue_len == MAX_PREQ_QUEUE_LEN) { 994 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock); 995 kfree(preq_node); 996 if (printk_ratelimit()) 997 mhwmp_dbg(sdata, "PREQ node queue full\n"); 998 return; 999 } 1000 1001 spin_lock(&mpath->state_lock); 1002 if (mpath->flags & MESH_PATH_REQ_QUEUED) { 1003 spin_unlock(&mpath->state_lock); 1004 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock); 1005 kfree(preq_node); 1006 return; 1007 } 1008 1009 memcpy(preq_node->dst, mpath->dst, ETH_ALEN); 1010 preq_node->flags = flags; 1011 1012 mpath->flags |= MESH_PATH_REQ_QUEUED; 1013 spin_unlock(&mpath->state_lock); 1014 1015 list_add_tail(&preq_node->list, &ifmsh->preq_queue.list); 1016 ++ifmsh->preq_queue_len; 1017 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock); 1018 1019 if (time_after(jiffies, ifmsh->last_preq + min_preq_int_jiff(sdata))) 1020 ieee80211_queue_work(&sdata->local->hw, &sdata->work); 1021 1022 else if (time_before(jiffies, ifmsh->last_preq)) { 1023 /* avoid long wait if did not send preqs for a long time 1024 * and jiffies wrapped around 1025 */ 1026 ifmsh->last_preq = jiffies - min_preq_int_jiff(sdata) - 1; 1027 ieee80211_queue_work(&sdata->local->hw, &sdata->work); 1028 } else 1029 mod_timer(&ifmsh->mesh_path_timer, ifmsh->last_preq + 1030 min_preq_int_jiff(sdata)); 1031 } 1032 1033 /** 1034 * mesh_path_start_discovery - launch a path discovery from the PREQ queue 1035 * 1036 * @sdata: local mesh subif 1037 */ 1038 void mesh_path_start_discovery(struct ieee80211_sub_if_data *sdata) 1039 { 1040 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 1041 struct mesh_preq_queue *preq_node; 1042 struct mesh_path *mpath; 1043 u8 ttl, target_flags = 0; 1044 const u8 *da; 1045 u32 lifetime; 1046 1047 spin_lock_bh(&ifmsh->mesh_preq_queue_lock); 1048 if (!ifmsh->preq_queue_len || 1049 time_before(jiffies, ifmsh->last_preq + 1050 min_preq_int_jiff(sdata))) { 1051 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock); 1052 return; 1053 } 1054 1055 preq_node = list_first_entry(&ifmsh->preq_queue.list, 1056 struct mesh_preq_queue, list); 1057 list_del(&preq_node->list); 1058 --ifmsh->preq_queue_len; 1059 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock); 1060 1061 rcu_read_lock(); 1062 mpath = mesh_path_lookup(sdata, preq_node->dst); 1063 if (!mpath) 1064 goto enddiscovery; 1065 1066 spin_lock_bh(&mpath->state_lock); 1067 if (mpath->flags & (MESH_PATH_DELETED | MESH_PATH_FIXED)) { 1068 spin_unlock_bh(&mpath->state_lock); 1069 goto enddiscovery; 1070 } 1071 mpath->flags &= ~MESH_PATH_REQ_QUEUED; 1072 if (preq_node->flags & PREQ_Q_F_START) { 1073 if (mpath->flags & MESH_PATH_RESOLVING) { 1074 spin_unlock_bh(&mpath->state_lock); 1075 goto enddiscovery; 1076 } else { 1077 mpath->flags &= ~MESH_PATH_RESOLVED; 1078 mpath->flags |= MESH_PATH_RESOLVING; 1079 mpath->discovery_retries = 0; 1080 mpath->discovery_timeout = disc_timeout_jiff(sdata); 1081 } 1082 } else if (!(mpath->flags & MESH_PATH_RESOLVING) || 1083 mpath->flags & MESH_PATH_RESOLVED) { 1084 mpath->flags &= ~MESH_PATH_RESOLVING; 1085 spin_unlock_bh(&mpath->state_lock); 1086 goto enddiscovery; 1087 } 1088 1089 ifmsh->last_preq = jiffies; 1090 1091 if (time_after(jiffies, ifmsh->last_sn_update + 1092 net_traversal_jiffies(sdata)) || 1093 time_before(jiffies, ifmsh->last_sn_update)) { 1094 ++ifmsh->sn; 1095 sdata->u.mesh.last_sn_update = jiffies; 1096 } 1097 lifetime = default_lifetime(sdata); 1098 ttl = sdata->u.mesh.mshcfg.element_ttl; 1099 if (ttl == 0) { 1100 sdata->u.mesh.mshstats.dropped_frames_ttl++; 1101 spin_unlock_bh(&mpath->state_lock); 1102 goto enddiscovery; 1103 } 1104 1105 if (preq_node->flags & PREQ_Q_F_REFRESH) 1106 target_flags |= IEEE80211_PREQ_TO_FLAG; 1107 else 1108 target_flags &= ~IEEE80211_PREQ_TO_FLAG; 1109 1110 spin_unlock_bh(&mpath->state_lock); 1111 da = (mpath->is_root) ? mpath->rann_snd_addr : broadcast_addr; 1112 mesh_path_sel_frame_tx(MPATH_PREQ, 0, sdata->vif.addr, ifmsh->sn, 1113 target_flags, mpath->dst, mpath->sn, da, 0, 1114 ttl, lifetime, 0, ifmsh->preq_id++, sdata); 1115 1116 spin_lock_bh(&mpath->state_lock); 1117 if (!(mpath->flags & MESH_PATH_DELETED)) 1118 mod_timer(&mpath->timer, jiffies + mpath->discovery_timeout); 1119 spin_unlock_bh(&mpath->state_lock); 1120 1121 enddiscovery: 1122 rcu_read_unlock(); 1123 kfree(preq_node); 1124 } 1125 1126 /** 1127 * mesh_nexthop_resolve - lookup next hop; conditionally start path discovery 1128 * 1129 * @skb: 802.11 frame to be sent 1130 * @sdata: network subif the frame will be sent through 1131 * 1132 * Lookup next hop for given skb and start path discovery if no 1133 * forwarding information is found. 1134 * 1135 * Returns: 0 if the next hop was found and -ENOENT if the frame was queued. 1136 * skb is freed here if no mpath could be allocated. 1137 */ 1138 int mesh_nexthop_resolve(struct ieee80211_sub_if_data *sdata, 1139 struct sk_buff *skb) 1140 { 1141 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 1142 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 1143 struct mesh_path *mpath; 1144 struct sk_buff *skb_to_free = NULL; 1145 u8 *target_addr = hdr->addr3; 1146 1147 /* Nulls are only sent to peers for PS and should be pre-addressed */ 1148 if (ieee80211_is_qos_nullfunc(hdr->frame_control)) 1149 return 0; 1150 1151 /* Allow injected packets to bypass mesh routing */ 1152 if (info->control.flags & IEEE80211_TX_CTRL_SKIP_MPATH_LOOKUP) 1153 return 0; 1154 1155 if (!mesh_nexthop_lookup(sdata, skb)) 1156 return 0; 1157 1158 /* no nexthop found, start resolving */ 1159 mpath = mesh_path_lookup(sdata, target_addr); 1160 if (!mpath) { 1161 mpath = mesh_path_add(sdata, target_addr); 1162 if (IS_ERR(mpath)) { 1163 mesh_path_discard_frame(sdata, skb); 1164 return PTR_ERR(mpath); 1165 } 1166 } 1167 1168 if (!(mpath->flags & MESH_PATH_RESOLVING) && 1169 mesh_path_sel_is_hwmp(sdata)) 1170 mesh_queue_preq(mpath, PREQ_Q_F_START); 1171 1172 if (skb_queue_len(&mpath->frame_queue) >= MESH_FRAME_QUEUE_LEN) 1173 skb_to_free = skb_dequeue(&mpath->frame_queue); 1174 1175 info->control.flags |= IEEE80211_TX_INTCFL_NEED_TXPROCESSING; 1176 ieee80211_set_qos_hdr(sdata, skb); 1177 skb_queue_tail(&mpath->frame_queue, skb); 1178 if (skb_to_free) 1179 mesh_path_discard_frame(sdata, skb_to_free); 1180 1181 return -ENOENT; 1182 } 1183 1184 /** 1185 * mesh_nexthop_lookup_nolearn - try to set next hop without path discovery 1186 * @skb: 802.11 frame to be sent 1187 * @sdata: network subif the frame will be sent through 1188 * 1189 * Check if the meshDA (addr3) of a unicast frame is a direct neighbor. 1190 * And if so, set the RA (addr1) to it to transmit to this node directly, 1191 * avoiding PREQ/PREP path discovery. 1192 * 1193 * Returns: 0 if the next hop was found and -ENOENT otherwise. 1194 */ 1195 static int mesh_nexthop_lookup_nolearn(struct ieee80211_sub_if_data *sdata, 1196 struct sk_buff *skb) 1197 { 1198 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 1199 struct sta_info *sta; 1200 1201 if (is_multicast_ether_addr(hdr->addr1)) 1202 return -ENOENT; 1203 1204 rcu_read_lock(); 1205 sta = sta_info_get(sdata, hdr->addr3); 1206 1207 if (!sta || sta->mesh->plink_state != NL80211_PLINK_ESTAB) { 1208 rcu_read_unlock(); 1209 return -ENOENT; 1210 } 1211 rcu_read_unlock(); 1212 1213 memcpy(hdr->addr1, hdr->addr3, ETH_ALEN); 1214 memcpy(hdr->addr2, sdata->vif.addr, ETH_ALEN); 1215 return 0; 1216 } 1217 1218 /** 1219 * mesh_nexthop_lookup - put the appropriate next hop on a mesh frame. Calling 1220 * this function is considered "using" the associated mpath, so preempt a path 1221 * refresh if this mpath expires soon. 1222 * 1223 * @skb: 802.11 frame to be sent 1224 * @sdata: network subif the frame will be sent through 1225 * 1226 * Returns: 0 if the next hop was found. Nonzero otherwise. 1227 */ 1228 int mesh_nexthop_lookup(struct ieee80211_sub_if_data *sdata, 1229 struct sk_buff *skb) 1230 { 1231 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 1232 struct mesh_path *mpath; 1233 struct sta_info *next_hop; 1234 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 1235 u8 *target_addr = hdr->addr3; 1236 1237 if (ifmsh->mshcfg.dot11MeshNolearn && 1238 !mesh_nexthop_lookup_nolearn(sdata, skb)) 1239 return 0; 1240 1241 mpath = mesh_path_lookup(sdata, target_addr); 1242 if (!mpath || !(mpath->flags & MESH_PATH_ACTIVE)) 1243 return -ENOENT; 1244 1245 if (time_after(jiffies, 1246 mpath->exp_time - 1247 msecs_to_jiffies(sdata->u.mesh.mshcfg.path_refresh_time)) && 1248 ether_addr_equal(sdata->vif.addr, hdr->addr4) && 1249 !(mpath->flags & MESH_PATH_RESOLVING) && 1250 !(mpath->flags & MESH_PATH_FIXED)) 1251 mesh_queue_preq(mpath, PREQ_Q_F_START | PREQ_Q_F_REFRESH); 1252 1253 next_hop = rcu_dereference(mpath->next_hop); 1254 if (next_hop) { 1255 memcpy(hdr->addr1, next_hop->sta.addr, ETH_ALEN); 1256 memcpy(hdr->addr2, sdata->vif.addr, ETH_ALEN); 1257 ieee80211_mps_set_frame_flags(sdata, next_hop, hdr); 1258 return 0; 1259 } 1260 1261 return -ENOENT; 1262 } 1263 1264 void mesh_path_timer(struct timer_list *t) 1265 { 1266 struct mesh_path *mpath = from_timer(mpath, t, timer); 1267 struct ieee80211_sub_if_data *sdata = mpath->sdata; 1268 int ret; 1269 1270 if (sdata->local->quiescing) 1271 return; 1272 1273 spin_lock_bh(&mpath->state_lock); 1274 if (mpath->flags & MESH_PATH_RESOLVED || 1275 (!(mpath->flags & MESH_PATH_RESOLVING))) { 1276 mpath->flags &= ~(MESH_PATH_RESOLVING | MESH_PATH_RESOLVED); 1277 spin_unlock_bh(&mpath->state_lock); 1278 } else if (mpath->discovery_retries < max_preq_retries(sdata)) { 1279 ++mpath->discovery_retries; 1280 mpath->discovery_timeout *= 2; 1281 mpath->flags &= ~MESH_PATH_REQ_QUEUED; 1282 spin_unlock_bh(&mpath->state_lock); 1283 mesh_queue_preq(mpath, 0); 1284 } else { 1285 mpath->flags &= ~(MESH_PATH_RESOLVING | 1286 MESH_PATH_RESOLVED | 1287 MESH_PATH_REQ_QUEUED); 1288 mpath->exp_time = jiffies; 1289 spin_unlock_bh(&mpath->state_lock); 1290 if (!mpath->is_gate && mesh_gate_num(sdata) > 0) { 1291 ret = mesh_path_send_to_gates(mpath); 1292 if (ret) 1293 mhwmp_dbg(sdata, "no gate was reachable\n"); 1294 } else 1295 mesh_path_flush_pending(mpath); 1296 } 1297 } 1298 1299 void mesh_path_tx_root_frame(struct ieee80211_sub_if_data *sdata) 1300 { 1301 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 1302 u32 interval = ifmsh->mshcfg.dot11MeshHWMPRannInterval; 1303 u8 flags, target_flags = 0; 1304 1305 flags = (ifmsh->mshcfg.dot11MeshGateAnnouncementProtocol) 1306 ? RANN_FLAG_IS_GATE : 0; 1307 1308 switch (ifmsh->mshcfg.dot11MeshHWMPRootMode) { 1309 case IEEE80211_PROACTIVE_RANN: 1310 mesh_path_sel_frame_tx(MPATH_RANN, flags, sdata->vif.addr, 1311 ++ifmsh->sn, 0, NULL, 0, broadcast_addr, 1312 0, ifmsh->mshcfg.element_ttl, 1313 interval, 0, 0, sdata); 1314 break; 1315 case IEEE80211_PROACTIVE_PREQ_WITH_PREP: 1316 flags |= IEEE80211_PREQ_PROACTIVE_PREP_FLAG; 1317 fallthrough; 1318 case IEEE80211_PROACTIVE_PREQ_NO_PREP: 1319 interval = ifmsh->mshcfg.dot11MeshHWMPactivePathToRootTimeout; 1320 target_flags |= IEEE80211_PREQ_TO_FLAG | 1321 IEEE80211_PREQ_USN_FLAG; 1322 mesh_path_sel_frame_tx(MPATH_PREQ, flags, sdata->vif.addr, 1323 ++ifmsh->sn, target_flags, 1324 (u8 *) broadcast_addr, 0, broadcast_addr, 1325 0, ifmsh->mshcfg.element_ttl, interval, 1326 0, ifmsh->preq_id++, sdata); 1327 break; 1328 default: 1329 mhwmp_dbg(sdata, "Proactive mechanism not supported\n"); 1330 return; 1331 } 1332 } 1333