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 10 #include <linux/slab.h> 11 #include <linux/etherdevice.h> 12 #include <asm/unaligned.h> 13 #include "wme.h" 14 #include "mesh.h" 15 16 #define TEST_FRAME_LEN 8192 17 #define MAX_METRIC 0xffffffff 18 #define ARITH_SHIFT 8 19 20 #define MAX_PREQ_QUEUE_LEN 64 21 22 static void mesh_queue_preq(struct mesh_path *, u8); 23 24 static inline u32 u32_field_get(const u8 *preq_elem, int offset, bool ae) 25 { 26 if (ae) 27 offset += 6; 28 return get_unaligned_le32(preq_elem + offset); 29 } 30 31 static inline u16 u16_field_get(const u8 *preq_elem, int offset, bool ae) 32 { 33 if (ae) 34 offset += 6; 35 return get_unaligned_le16(preq_elem + offset); 36 } 37 38 /* HWMP IE processing macros */ 39 #define AE_F (1<<6) 40 #define AE_F_SET(x) (*x & AE_F) 41 #define PREQ_IE_FLAGS(x) (*(x)) 42 #define PREQ_IE_HOPCOUNT(x) (*(x + 1)) 43 #define PREQ_IE_TTL(x) (*(x + 2)) 44 #define PREQ_IE_PREQ_ID(x) u32_field_get(x, 3, 0) 45 #define PREQ_IE_ORIG_ADDR(x) (x + 7) 46 #define PREQ_IE_ORIG_SN(x) u32_field_get(x, 13, 0) 47 #define PREQ_IE_LIFETIME(x) u32_field_get(x, 17, AE_F_SET(x)) 48 #define PREQ_IE_METRIC(x) u32_field_get(x, 21, AE_F_SET(x)) 49 #define PREQ_IE_TARGET_F(x) (*(AE_F_SET(x) ? x + 32 : x + 26)) 50 #define PREQ_IE_TARGET_ADDR(x) (AE_F_SET(x) ? x + 33 : x + 27) 51 #define PREQ_IE_TARGET_SN(x) u32_field_get(x, 33, AE_F_SET(x)) 52 53 54 #define PREP_IE_FLAGS(x) PREQ_IE_FLAGS(x) 55 #define PREP_IE_HOPCOUNT(x) PREQ_IE_HOPCOUNT(x) 56 #define PREP_IE_TTL(x) PREQ_IE_TTL(x) 57 #define PREP_IE_ORIG_ADDR(x) (AE_F_SET(x) ? x + 27 : x + 21) 58 #define PREP_IE_ORIG_SN(x) u32_field_get(x, 27, AE_F_SET(x)) 59 #define PREP_IE_LIFETIME(x) u32_field_get(x, 13, AE_F_SET(x)) 60 #define PREP_IE_METRIC(x) u32_field_get(x, 17, AE_F_SET(x)) 61 #define PREP_IE_TARGET_ADDR(x) (x + 3) 62 #define PREP_IE_TARGET_SN(x) u32_field_get(x, 9, 0) 63 64 #define PERR_IE_TTL(x) (*(x)) 65 #define PERR_IE_TARGET_FLAGS(x) (*(x + 2)) 66 #define PERR_IE_TARGET_ADDR(x) (x + 3) 67 #define PERR_IE_TARGET_SN(x) u32_field_get(x, 9, 0) 68 #define PERR_IE_TARGET_RCODE(x) u16_field_get(x, 13, 0) 69 70 #define MSEC_TO_TU(x) (x*1000/1024) 71 #define SN_GT(x, y) ((s32)(y - x) < 0) 72 #define SN_LT(x, y) ((s32)(x - y) < 0) 73 #define MAX_SANE_SN_DELTA 32 74 75 static inline u32 SN_DELTA(u32 x, u32 y) 76 { 77 return x >= y ? x - y : y - x; 78 } 79 80 #define net_traversal_jiffies(s) \ 81 msecs_to_jiffies(s->u.mesh.mshcfg.dot11MeshHWMPnetDiameterTraversalTime) 82 #define default_lifetime(s) \ 83 MSEC_TO_TU(s->u.mesh.mshcfg.dot11MeshHWMPactivePathTimeout) 84 #define min_preq_int_jiff(s) \ 85 (msecs_to_jiffies(s->u.mesh.mshcfg.dot11MeshHWMPpreqMinInterval)) 86 #define max_preq_retries(s) (s->u.mesh.mshcfg.dot11MeshHWMPmaxPREQretries) 87 #define disc_timeout_jiff(s) \ 88 msecs_to_jiffies(sdata->u.mesh.mshcfg.min_discovery_timeout) 89 #define root_path_confirmation_jiffies(s) \ 90 msecs_to_jiffies(sdata->u.mesh.mshcfg.dot11MeshHWMPconfirmationInterval) 91 92 enum mpath_frame_type { 93 MPATH_PREQ = 0, 94 MPATH_PREP, 95 MPATH_PERR, 96 MPATH_RANN 97 }; 98 99 static const u8 broadcast_addr[ETH_ALEN] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff}; 100 101 static int mesh_path_sel_frame_tx(enum mpath_frame_type action, u8 flags, 102 const u8 *orig_addr, u32 orig_sn, 103 u8 target_flags, const u8 *target, 104 u32 target_sn, const u8 *da, 105 u8 hop_count, u8 ttl, 106 u32 lifetime, u32 metric, u32 preq_id, 107 struct ieee80211_sub_if_data *sdata) 108 { 109 struct ieee80211_local *local = sdata->local; 110 struct sk_buff *skb; 111 struct ieee80211_mgmt *mgmt; 112 u8 *pos, ie_len; 113 int hdr_len = offsetof(struct ieee80211_mgmt, u.action.u.mesh_action) + 114 sizeof(mgmt->u.action.u.mesh_action); 115 116 skb = dev_alloc_skb(local->tx_headroom + 117 hdr_len + 118 2 + 37); /* max HWMP IE */ 119 if (!skb) 120 return -1; 121 skb_reserve(skb, local->tx_headroom); 122 mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len); 123 memset(mgmt, 0, hdr_len); 124 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 125 IEEE80211_STYPE_ACTION); 126 127 memcpy(mgmt->da, da, ETH_ALEN); 128 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN); 129 /* BSSID == SA */ 130 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN); 131 mgmt->u.action.category = WLAN_CATEGORY_MESH_ACTION; 132 mgmt->u.action.u.mesh_action.action_code = 133 WLAN_MESH_ACTION_HWMP_PATH_SELECTION; 134 135 switch (action) { 136 case MPATH_PREQ: 137 mhwmp_dbg(sdata, "sending PREQ to %pM\n", target); 138 ie_len = 37; 139 pos = skb_put(skb, 2 + ie_len); 140 *pos++ = WLAN_EID_PREQ; 141 break; 142 case MPATH_PREP: 143 mhwmp_dbg(sdata, "sending PREP to %pM\n", orig_addr); 144 ie_len = 31; 145 pos = skb_put(skb, 2 + ie_len); 146 *pos++ = WLAN_EID_PREP; 147 break; 148 case MPATH_RANN: 149 mhwmp_dbg(sdata, "sending RANN from %pM\n", orig_addr); 150 ie_len = sizeof(struct ieee80211_rann_ie); 151 pos = skb_put(skb, 2 + ie_len); 152 *pos++ = WLAN_EID_RANN; 153 break; 154 default: 155 kfree_skb(skb); 156 return -ENOTSUPP; 157 } 158 *pos++ = ie_len; 159 *pos++ = flags; 160 *pos++ = hop_count; 161 *pos++ = ttl; 162 if (action == MPATH_PREP) { 163 memcpy(pos, target, ETH_ALEN); 164 pos += ETH_ALEN; 165 put_unaligned_le32(target_sn, pos); 166 pos += 4; 167 } else { 168 if (action == MPATH_PREQ) { 169 put_unaligned_le32(preq_id, pos); 170 pos += 4; 171 } 172 memcpy(pos, orig_addr, ETH_ALEN); 173 pos += ETH_ALEN; 174 put_unaligned_le32(orig_sn, pos); 175 pos += 4; 176 } 177 put_unaligned_le32(lifetime, pos); /* interval for RANN */ 178 pos += 4; 179 put_unaligned_le32(metric, pos); 180 pos += 4; 181 if (action == MPATH_PREQ) { 182 *pos++ = 1; /* destination count */ 183 *pos++ = target_flags; 184 memcpy(pos, target, ETH_ALEN); 185 pos += ETH_ALEN; 186 put_unaligned_le32(target_sn, pos); 187 pos += 4; 188 } else if (action == MPATH_PREP) { 189 memcpy(pos, orig_addr, ETH_ALEN); 190 pos += ETH_ALEN; 191 put_unaligned_le32(orig_sn, pos); 192 pos += 4; 193 } 194 195 ieee80211_tx_skb(sdata, skb); 196 return 0; 197 } 198 199 200 /* Headroom is not adjusted. Caller should ensure that skb has sufficient 201 * headroom in case the frame is encrypted. */ 202 static void prepare_frame_for_deferred_tx(struct ieee80211_sub_if_data *sdata, 203 struct sk_buff *skb) 204 { 205 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 206 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 207 208 skb_reset_mac_header(skb); 209 skb_reset_network_header(skb); 210 skb_reset_transport_header(skb); 211 212 /* Send all internal mgmt frames on VO. Accordingly set TID to 7. */ 213 skb_set_queue_mapping(skb, IEEE80211_AC_VO); 214 skb->priority = 7; 215 216 info->control.vif = &sdata->vif; 217 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING; 218 ieee80211_set_qos_hdr(sdata, skb); 219 ieee80211_mps_set_frame_flags(sdata, NULL, hdr); 220 } 221 222 /** 223 * mesh_path_error_tx - Sends a PERR mesh management frame 224 * 225 * @ttl: allowed remaining hops 226 * @target: broken destination 227 * @target_sn: SN of the broken destination 228 * @target_rcode: reason code for this PERR 229 * @ra: node this frame is addressed to 230 * @sdata: local mesh subif 231 * 232 * Note: This function may be called with driver locks taken that the driver 233 * also acquires in the TX path. To avoid a deadlock we don't transmit the 234 * frame directly but add it to the pending queue instead. 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 = offsetof(struct ieee80211_mgmt, u.action.u.mesh_action) + 246 sizeof(mgmt->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 sdata->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 + sdata->encrypt_headroom); 259 mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len); 260 memset(mgmt, 0, hdr_len); 261 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 262 IEEE80211_STYPE_ACTION); 263 264 memcpy(mgmt->da, ra, ETH_ALEN); 265 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN); 266 /* BSSID == SA */ 267 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN); 268 mgmt->u.action.category = WLAN_CATEGORY_MESH_ACTION; 269 mgmt->u.action.u.mesh_action.action_code = 270 WLAN_MESH_ACTION_HWMP_PATH_SELECTION; 271 ie_len = 15; 272 pos = skb_put(skb, 2 + ie_len); 273 *pos++ = WLAN_EID_PERR; 274 *pos++ = ie_len; 275 /* ttl */ 276 *pos++ = ttl; 277 /* number of destinations */ 278 *pos++ = 1; 279 /* Flags field has AE bit only as defined in 280 * sec 8.4.2.117 IEEE802.11-2012 281 */ 282 *pos = 0; 283 pos++; 284 memcpy(pos, target, ETH_ALEN); 285 pos += ETH_ALEN; 286 put_unaligned_le32(target_sn, pos); 287 pos += 4; 288 put_unaligned_le16(target_rcode, pos); 289 290 /* see note in function header */ 291 prepare_frame_for_deferred_tx(sdata, skb); 292 ifmsh->next_perr = TU_TO_EXP_TIME( 293 ifmsh->mshcfg.dot11MeshHWMPperrMinInterval); 294 ieee80211_add_pending_skb(local, skb); 295 return 0; 296 } 297 298 void ieee80211s_update_metric(struct ieee80211_local *local, 299 struct sta_info *sta, struct sk_buff *skb) 300 { 301 struct ieee80211_tx_info *txinfo = IEEE80211_SKB_CB(skb); 302 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 303 int failed; 304 305 if (!ieee80211_is_data(hdr->frame_control)) 306 return; 307 308 failed = !(txinfo->flags & IEEE80211_TX_STAT_ACK); 309 310 /* moving average, scaled to 100 */ 311 sta->mesh->fail_avg = 312 ((80 * sta->mesh->fail_avg + 5) / 100 + 20 * failed); 313 if (sta->mesh->fail_avg > 95) 314 mesh_plink_broken(sta); 315 } 316 317 static u32 airtime_link_metric_get(struct ieee80211_local *local, 318 struct sta_info *sta) 319 { 320 struct rate_info rinfo; 321 /* This should be adjusted for each device */ 322 int device_constant = 1 << ARITH_SHIFT; 323 int test_frame_len = TEST_FRAME_LEN << ARITH_SHIFT; 324 int s_unit = 1 << ARITH_SHIFT; 325 int rate, err; 326 u32 tx_time, estimated_retx; 327 u64 result; 328 329 if (sta->mesh->fail_avg >= 100) 330 return MAX_METRIC; 331 332 sta_set_rate_info_tx(sta, &sta->tx_stats.last_rate, &rinfo); 333 rate = cfg80211_calculate_bitrate(&rinfo); 334 if (WARN_ON(!rate)) 335 return MAX_METRIC; 336 337 err = (sta->mesh->fail_avg << ARITH_SHIFT) / 100; 338 339 /* bitrate is in units of 100 Kbps, while we need rate in units of 340 * 1Mbps. This will be corrected on tx_time computation. 341 */ 342 tx_time = (device_constant + 10 * test_frame_len / rate); 343 estimated_retx = ((1 << (2 * ARITH_SHIFT)) / (s_unit - err)); 344 result = (tx_time * estimated_retx) >> (2 * ARITH_SHIFT) ; 345 return (u32)result; 346 } 347 348 /** 349 * hwmp_route_info_get - Update routing info to originator and transmitter 350 * 351 * @sdata: local mesh subif 352 * @mgmt: mesh management frame 353 * @hwmp_ie: hwmp information element (PREP or PREQ) 354 * @action: type of hwmp ie 355 * 356 * This function updates the path routing information to the originator and the 357 * transmitter of a HWMP PREQ or PREP frame. 358 * 359 * Returns: metric to frame originator or 0 if the frame should not be further 360 * processed 361 * 362 * Notes: this function is the only place (besides user-provided info) where 363 * path routing information is updated. 364 */ 365 static u32 hwmp_route_info_get(struct ieee80211_sub_if_data *sdata, 366 struct ieee80211_mgmt *mgmt, 367 const u8 *hwmp_ie, enum mpath_frame_type action) 368 { 369 struct ieee80211_local *local = sdata->local; 370 struct mesh_path *mpath; 371 struct sta_info *sta; 372 bool fresh_info; 373 const u8 *orig_addr, *ta; 374 u32 orig_sn, orig_metric; 375 unsigned long orig_lifetime, exp_time; 376 u32 last_hop_metric, new_metric; 377 bool process = true; 378 379 rcu_read_lock(); 380 sta = sta_info_get(sdata, mgmt->sa); 381 if (!sta) { 382 rcu_read_unlock(); 383 return 0; 384 } 385 386 last_hop_metric = airtime_link_metric_get(local, sta); 387 /* Update and check originator routing info */ 388 fresh_info = true; 389 390 switch (action) { 391 case MPATH_PREQ: 392 orig_addr = PREQ_IE_ORIG_ADDR(hwmp_ie); 393 orig_sn = PREQ_IE_ORIG_SN(hwmp_ie); 394 orig_lifetime = PREQ_IE_LIFETIME(hwmp_ie); 395 orig_metric = PREQ_IE_METRIC(hwmp_ie); 396 break; 397 case MPATH_PREP: 398 /* Originator here refers to the MP that was the target in the 399 * Path Request. We divert from the nomenclature in the draft 400 * so that we can easily use a single function to gather path 401 * information from both PREQ and PREP frames. 402 */ 403 orig_addr = PREP_IE_TARGET_ADDR(hwmp_ie); 404 orig_sn = PREP_IE_TARGET_SN(hwmp_ie); 405 orig_lifetime = PREP_IE_LIFETIME(hwmp_ie); 406 orig_metric = PREP_IE_METRIC(hwmp_ie); 407 break; 408 default: 409 rcu_read_unlock(); 410 return 0; 411 } 412 new_metric = orig_metric + last_hop_metric; 413 if (new_metric < orig_metric) 414 new_metric = MAX_METRIC; 415 exp_time = TU_TO_EXP_TIME(orig_lifetime); 416 417 if (ether_addr_equal(orig_addr, sdata->vif.addr)) { 418 /* This MP is the originator, we are not interested in this 419 * frame, except for updating transmitter's path info. 420 */ 421 process = false; 422 fresh_info = false; 423 } else { 424 mpath = mesh_path_lookup(sdata, orig_addr); 425 if (mpath) { 426 spin_lock_bh(&mpath->state_lock); 427 if (mpath->flags & MESH_PATH_FIXED) 428 fresh_info = false; 429 else if ((mpath->flags & MESH_PATH_ACTIVE) && 430 (mpath->flags & MESH_PATH_SN_VALID)) { 431 if (SN_GT(mpath->sn, orig_sn) || 432 (mpath->sn == orig_sn && 433 new_metric >= mpath->metric)) { 434 process = false; 435 fresh_info = false; 436 } 437 } else if (!(mpath->flags & MESH_PATH_ACTIVE)) { 438 bool have_sn, newer_sn, bounced; 439 440 have_sn = mpath->flags & MESH_PATH_SN_VALID; 441 newer_sn = have_sn && SN_GT(orig_sn, mpath->sn); 442 bounced = have_sn && 443 (SN_DELTA(orig_sn, mpath->sn) > 444 MAX_SANE_SN_DELTA); 445 446 if (!have_sn || newer_sn) { 447 /* if SN is newer than what we had 448 * then we can take it */; 449 } else if (bounced) { 450 /* if SN is way different than what 451 * we had then assume the other side 452 * rebooted or restarted */; 453 } else { 454 process = false; 455 fresh_info = false; 456 } 457 } 458 } else { 459 mpath = mesh_path_add(sdata, orig_addr); 460 if (IS_ERR(mpath)) { 461 rcu_read_unlock(); 462 return 0; 463 } 464 spin_lock_bh(&mpath->state_lock); 465 } 466 467 if (fresh_info) { 468 mesh_path_assign_nexthop(mpath, sta); 469 mpath->flags |= MESH_PATH_SN_VALID; 470 mpath->metric = new_metric; 471 mpath->sn = orig_sn; 472 mpath->exp_time = time_after(mpath->exp_time, exp_time) 473 ? mpath->exp_time : exp_time; 474 mesh_path_activate(mpath); 475 spin_unlock_bh(&mpath->state_lock); 476 mesh_path_tx_pending(mpath); 477 /* draft says preq_id should be saved to, but there does 478 * not seem to be any use for it, skipping by now 479 */ 480 } else 481 spin_unlock_bh(&mpath->state_lock); 482 } 483 484 /* Update and check transmitter routing info */ 485 ta = mgmt->sa; 486 if (ether_addr_equal(orig_addr, ta)) 487 fresh_info = false; 488 else { 489 fresh_info = true; 490 491 mpath = mesh_path_lookup(sdata, ta); 492 if (mpath) { 493 spin_lock_bh(&mpath->state_lock); 494 if ((mpath->flags & MESH_PATH_FIXED) || 495 ((mpath->flags & MESH_PATH_ACTIVE) && 496 (last_hop_metric > mpath->metric))) 497 fresh_info = false; 498 } else { 499 mpath = mesh_path_add(sdata, ta); 500 if (IS_ERR(mpath)) { 501 rcu_read_unlock(); 502 return 0; 503 } 504 spin_lock_bh(&mpath->state_lock); 505 } 506 507 if (fresh_info) { 508 mesh_path_assign_nexthop(mpath, sta); 509 mpath->metric = last_hop_metric; 510 mpath->exp_time = time_after(mpath->exp_time, exp_time) 511 ? mpath->exp_time : exp_time; 512 mesh_path_activate(mpath); 513 spin_unlock_bh(&mpath->state_lock); 514 mesh_path_tx_pending(mpath); 515 } else 516 spin_unlock_bh(&mpath->state_lock); 517 } 518 519 rcu_read_unlock(); 520 521 return process ? new_metric : 0; 522 } 523 524 static void hwmp_preq_frame_process(struct ieee80211_sub_if_data *sdata, 525 struct ieee80211_mgmt *mgmt, 526 const u8 *preq_elem, u32 orig_metric) 527 { 528 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 529 struct mesh_path *mpath = NULL; 530 const u8 *target_addr, *orig_addr; 531 const u8 *da; 532 u8 target_flags, ttl, flags; 533 u32 orig_sn, target_sn, lifetime, target_metric = 0; 534 bool reply = false; 535 bool forward = true; 536 bool root_is_gate; 537 538 /* Update target SN, if present */ 539 target_addr = PREQ_IE_TARGET_ADDR(preq_elem); 540 orig_addr = PREQ_IE_ORIG_ADDR(preq_elem); 541 target_sn = PREQ_IE_TARGET_SN(preq_elem); 542 orig_sn = PREQ_IE_ORIG_SN(preq_elem); 543 target_flags = PREQ_IE_TARGET_F(preq_elem); 544 /* Proactive PREQ gate announcements */ 545 flags = PREQ_IE_FLAGS(preq_elem); 546 root_is_gate = !!(flags & RANN_FLAG_IS_GATE); 547 548 mhwmp_dbg(sdata, "received PREQ from %pM\n", orig_addr); 549 550 if (ether_addr_equal(target_addr, sdata->vif.addr)) { 551 mhwmp_dbg(sdata, "PREQ is for us\n"); 552 forward = false; 553 reply = true; 554 target_metric = 0; 555 if (time_after(jiffies, ifmsh->last_sn_update + 556 net_traversal_jiffies(sdata)) || 557 time_before(jiffies, ifmsh->last_sn_update)) { 558 ++ifmsh->sn; 559 ifmsh->last_sn_update = jiffies; 560 } 561 target_sn = ifmsh->sn; 562 } else if (is_broadcast_ether_addr(target_addr) && 563 (target_flags & IEEE80211_PREQ_TO_FLAG)) { 564 rcu_read_lock(); 565 mpath = mesh_path_lookup(sdata, orig_addr); 566 if (mpath) { 567 if (flags & IEEE80211_PREQ_PROACTIVE_PREP_FLAG) { 568 reply = true; 569 target_addr = sdata->vif.addr; 570 target_sn = ++ifmsh->sn; 571 target_metric = 0; 572 ifmsh->last_sn_update = jiffies; 573 } 574 if (root_is_gate) 575 mesh_path_add_gate(mpath); 576 } 577 rcu_read_unlock(); 578 } else { 579 rcu_read_lock(); 580 mpath = mesh_path_lookup(sdata, target_addr); 581 if (mpath) { 582 if ((!(mpath->flags & MESH_PATH_SN_VALID)) || 583 SN_LT(mpath->sn, target_sn)) { 584 mpath->sn = target_sn; 585 mpath->flags |= MESH_PATH_SN_VALID; 586 } else if ((!(target_flags & IEEE80211_PREQ_TO_FLAG)) && 587 (mpath->flags & MESH_PATH_ACTIVE)) { 588 reply = true; 589 target_metric = mpath->metric; 590 target_sn = mpath->sn; 591 /* Case E2 of sec 13.10.9.3 IEEE 802.11-2012*/ 592 target_flags |= IEEE80211_PREQ_TO_FLAG; 593 } 594 } 595 rcu_read_unlock(); 596 } 597 598 if (reply) { 599 lifetime = PREQ_IE_LIFETIME(preq_elem); 600 ttl = ifmsh->mshcfg.element_ttl; 601 if (ttl != 0) { 602 mhwmp_dbg(sdata, "replying to the PREQ\n"); 603 mesh_path_sel_frame_tx(MPATH_PREP, 0, orig_addr, 604 orig_sn, 0, target_addr, 605 target_sn, mgmt->sa, 0, ttl, 606 lifetime, target_metric, 0, 607 sdata); 608 } else { 609 ifmsh->mshstats.dropped_frames_ttl++; 610 } 611 } 612 613 if (forward && ifmsh->mshcfg.dot11MeshForwarding) { 614 u32 preq_id; 615 u8 hopcount; 616 617 ttl = PREQ_IE_TTL(preq_elem); 618 lifetime = PREQ_IE_LIFETIME(preq_elem); 619 if (ttl <= 1) { 620 ifmsh->mshstats.dropped_frames_ttl++; 621 return; 622 } 623 mhwmp_dbg(sdata, "forwarding the PREQ from %pM\n", orig_addr); 624 --ttl; 625 preq_id = PREQ_IE_PREQ_ID(preq_elem); 626 hopcount = PREQ_IE_HOPCOUNT(preq_elem) + 1; 627 da = (mpath && mpath->is_root) ? 628 mpath->rann_snd_addr : broadcast_addr; 629 630 if (flags & IEEE80211_PREQ_PROACTIVE_PREP_FLAG) { 631 target_addr = PREQ_IE_TARGET_ADDR(preq_elem); 632 target_sn = PREQ_IE_TARGET_SN(preq_elem); 633 } 634 635 mesh_path_sel_frame_tx(MPATH_PREQ, flags, orig_addr, 636 orig_sn, target_flags, target_addr, 637 target_sn, da, hopcount, ttl, lifetime, 638 orig_metric, preq_id, sdata); 639 if (!is_multicast_ether_addr(da)) 640 ifmsh->mshstats.fwded_unicast++; 641 else 642 ifmsh->mshstats.fwded_mcast++; 643 ifmsh->mshstats.fwded_frames++; 644 } 645 } 646 647 648 static inline struct sta_info * 649 next_hop_deref_protected(struct mesh_path *mpath) 650 { 651 return rcu_dereference_protected(mpath->next_hop, 652 lockdep_is_held(&mpath->state_lock)); 653 } 654 655 656 static void hwmp_prep_frame_process(struct ieee80211_sub_if_data *sdata, 657 struct ieee80211_mgmt *mgmt, 658 const u8 *prep_elem, u32 metric) 659 { 660 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 661 struct mesh_path *mpath; 662 const u8 *target_addr, *orig_addr; 663 u8 ttl, hopcount, flags; 664 u8 next_hop[ETH_ALEN]; 665 u32 target_sn, orig_sn, lifetime; 666 667 mhwmp_dbg(sdata, "received PREP from %pM\n", 668 PREP_IE_TARGET_ADDR(prep_elem)); 669 670 orig_addr = PREP_IE_ORIG_ADDR(prep_elem); 671 if (ether_addr_equal(orig_addr, sdata->vif.addr)) 672 /* destination, no forwarding required */ 673 return; 674 675 if (!ifmsh->mshcfg.dot11MeshForwarding) 676 return; 677 678 ttl = PREP_IE_TTL(prep_elem); 679 if (ttl <= 1) { 680 sdata->u.mesh.mshstats.dropped_frames_ttl++; 681 return; 682 } 683 684 rcu_read_lock(); 685 mpath = mesh_path_lookup(sdata, orig_addr); 686 if (mpath) 687 spin_lock_bh(&mpath->state_lock); 688 else 689 goto fail; 690 if (!(mpath->flags & MESH_PATH_ACTIVE)) { 691 spin_unlock_bh(&mpath->state_lock); 692 goto fail; 693 } 694 memcpy(next_hop, next_hop_deref_protected(mpath)->sta.addr, ETH_ALEN); 695 spin_unlock_bh(&mpath->state_lock); 696 --ttl; 697 flags = PREP_IE_FLAGS(prep_elem); 698 lifetime = PREP_IE_LIFETIME(prep_elem); 699 hopcount = PREP_IE_HOPCOUNT(prep_elem) + 1; 700 target_addr = PREP_IE_TARGET_ADDR(prep_elem); 701 target_sn = PREP_IE_TARGET_SN(prep_elem); 702 orig_sn = PREP_IE_ORIG_SN(prep_elem); 703 704 mesh_path_sel_frame_tx(MPATH_PREP, flags, orig_addr, orig_sn, 0, 705 target_addr, target_sn, next_hop, hopcount, 706 ttl, lifetime, metric, 0, sdata); 707 rcu_read_unlock(); 708 709 sdata->u.mesh.mshstats.fwded_unicast++; 710 sdata->u.mesh.mshstats.fwded_frames++; 711 return; 712 713 fail: 714 rcu_read_unlock(); 715 sdata->u.mesh.mshstats.dropped_frames_no_route++; 716 } 717 718 static void hwmp_perr_frame_process(struct ieee80211_sub_if_data *sdata, 719 struct ieee80211_mgmt *mgmt, 720 const u8 *perr_elem) 721 { 722 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 723 struct mesh_path *mpath; 724 u8 ttl; 725 const u8 *ta, *target_addr; 726 u32 target_sn; 727 u16 target_rcode; 728 729 ta = mgmt->sa; 730 ttl = PERR_IE_TTL(perr_elem); 731 if (ttl <= 1) { 732 ifmsh->mshstats.dropped_frames_ttl++; 733 return; 734 } 735 ttl--; 736 target_addr = PERR_IE_TARGET_ADDR(perr_elem); 737 target_sn = PERR_IE_TARGET_SN(perr_elem); 738 target_rcode = PERR_IE_TARGET_RCODE(perr_elem); 739 740 rcu_read_lock(); 741 mpath = mesh_path_lookup(sdata, target_addr); 742 if (mpath) { 743 struct sta_info *sta; 744 745 spin_lock_bh(&mpath->state_lock); 746 sta = next_hop_deref_protected(mpath); 747 if (mpath->flags & MESH_PATH_ACTIVE && 748 ether_addr_equal(ta, sta->sta.addr) && 749 (!(mpath->flags & MESH_PATH_SN_VALID) || 750 SN_GT(target_sn, mpath->sn) || target_sn == 0)) { 751 mpath->flags &= ~MESH_PATH_ACTIVE; 752 if (target_sn != 0) 753 mpath->sn = target_sn; 754 else 755 mpath->sn += 1; 756 spin_unlock_bh(&mpath->state_lock); 757 if (!ifmsh->mshcfg.dot11MeshForwarding) 758 goto endperr; 759 mesh_path_error_tx(sdata, ttl, target_addr, 760 target_sn, target_rcode, 761 broadcast_addr); 762 } else 763 spin_unlock_bh(&mpath->state_lock); 764 } 765 endperr: 766 rcu_read_unlock(); 767 } 768 769 static void hwmp_rann_frame_process(struct ieee80211_sub_if_data *sdata, 770 struct ieee80211_mgmt *mgmt, 771 const struct ieee80211_rann_ie *rann) 772 { 773 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 774 struct ieee80211_local *local = sdata->local; 775 struct sta_info *sta; 776 struct mesh_path *mpath; 777 u8 ttl, flags, hopcount; 778 const u8 *orig_addr; 779 u32 orig_sn, metric, metric_txsta, interval; 780 bool root_is_gate; 781 782 ttl = rann->rann_ttl; 783 flags = rann->rann_flags; 784 root_is_gate = !!(flags & RANN_FLAG_IS_GATE); 785 orig_addr = rann->rann_addr; 786 orig_sn = le32_to_cpu(rann->rann_seq); 787 interval = le32_to_cpu(rann->rann_interval); 788 hopcount = rann->rann_hopcount; 789 hopcount++; 790 metric = le32_to_cpu(rann->rann_metric); 791 792 /* Ignore our own RANNs */ 793 if (ether_addr_equal(orig_addr, sdata->vif.addr)) 794 return; 795 796 mhwmp_dbg(sdata, 797 "received RANN from %pM via neighbour %pM (is_gate=%d)\n", 798 orig_addr, mgmt->sa, root_is_gate); 799 800 rcu_read_lock(); 801 sta = sta_info_get(sdata, mgmt->sa); 802 if (!sta) { 803 rcu_read_unlock(); 804 return; 805 } 806 807 metric_txsta = airtime_link_metric_get(local, sta); 808 809 mpath = mesh_path_lookup(sdata, orig_addr); 810 if (!mpath) { 811 mpath = mesh_path_add(sdata, orig_addr); 812 if (IS_ERR(mpath)) { 813 rcu_read_unlock(); 814 sdata->u.mesh.mshstats.dropped_frames_no_route++; 815 return; 816 } 817 } 818 819 if (!(SN_LT(mpath->sn, orig_sn)) && 820 !(mpath->sn == orig_sn && metric < mpath->rann_metric)) { 821 rcu_read_unlock(); 822 return; 823 } 824 825 if ((!(mpath->flags & (MESH_PATH_ACTIVE | MESH_PATH_RESOLVING)) || 826 (time_after(jiffies, mpath->last_preq_to_root + 827 root_path_confirmation_jiffies(sdata)) || 828 time_before(jiffies, mpath->last_preq_to_root))) && 829 !(mpath->flags & MESH_PATH_FIXED) && (ttl != 0)) { 830 mhwmp_dbg(sdata, 831 "time to refresh root mpath %pM\n", 832 orig_addr); 833 mesh_queue_preq(mpath, PREQ_Q_F_START | PREQ_Q_F_REFRESH); 834 mpath->last_preq_to_root = jiffies; 835 } 836 837 mpath->sn = orig_sn; 838 mpath->rann_metric = metric + metric_txsta; 839 mpath->is_root = true; 840 /* Recording RANNs sender address to send individually 841 * addressed PREQs destined for root mesh STA */ 842 memcpy(mpath->rann_snd_addr, mgmt->sa, ETH_ALEN); 843 844 if (root_is_gate) 845 mesh_path_add_gate(mpath); 846 847 if (ttl <= 1) { 848 ifmsh->mshstats.dropped_frames_ttl++; 849 rcu_read_unlock(); 850 return; 851 } 852 ttl--; 853 854 if (ifmsh->mshcfg.dot11MeshForwarding) { 855 mesh_path_sel_frame_tx(MPATH_RANN, flags, orig_addr, 856 orig_sn, 0, NULL, 0, broadcast_addr, 857 hopcount, ttl, interval, 858 metric + metric_txsta, 0, sdata); 859 } 860 861 rcu_read_unlock(); 862 } 863 864 865 void mesh_rx_path_sel_frame(struct ieee80211_sub_if_data *sdata, 866 struct ieee80211_mgmt *mgmt, size_t len) 867 { 868 struct ieee802_11_elems elems; 869 size_t baselen; 870 u32 path_metric; 871 struct sta_info *sta; 872 873 /* need action_code */ 874 if (len < IEEE80211_MIN_ACTION_SIZE + 1) 875 return; 876 877 rcu_read_lock(); 878 sta = sta_info_get(sdata, mgmt->sa); 879 if (!sta || sta->mesh->plink_state != NL80211_PLINK_ESTAB) { 880 rcu_read_unlock(); 881 return; 882 } 883 rcu_read_unlock(); 884 885 baselen = (u8 *) mgmt->u.action.u.mesh_action.variable - (u8 *) mgmt; 886 ieee802_11_parse_elems(mgmt->u.action.u.mesh_action.variable, 887 len - baselen, false, &elems); 888 889 if (elems.preq) { 890 if (elems.preq_len != 37) 891 /* Right now we support just 1 destination and no AE */ 892 return; 893 path_metric = hwmp_route_info_get(sdata, mgmt, elems.preq, 894 MPATH_PREQ); 895 if (path_metric) 896 hwmp_preq_frame_process(sdata, mgmt, elems.preq, 897 path_metric); 898 } 899 if (elems.prep) { 900 if (elems.prep_len != 31) 901 /* Right now we support no AE */ 902 return; 903 path_metric = hwmp_route_info_get(sdata, mgmt, elems.prep, 904 MPATH_PREP); 905 if (path_metric) 906 hwmp_prep_frame_process(sdata, mgmt, elems.prep, 907 path_metric); 908 } 909 if (elems.perr) { 910 if (elems.perr_len != 15) 911 /* Right now we support only one destination per PERR */ 912 return; 913 hwmp_perr_frame_process(sdata, mgmt, elems.perr); 914 } 915 if (elems.rann) 916 hwmp_rann_frame_process(sdata, mgmt, elems.rann); 917 } 918 919 /** 920 * mesh_queue_preq - queue a PREQ to a given destination 921 * 922 * @mpath: mesh path to discover 923 * @flags: special attributes of the PREQ to be sent 924 * 925 * Locking: the function must be called from within a rcu read lock block. 926 * 927 */ 928 static void mesh_queue_preq(struct mesh_path *mpath, u8 flags) 929 { 930 struct ieee80211_sub_if_data *sdata = mpath->sdata; 931 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 932 struct mesh_preq_queue *preq_node; 933 934 preq_node = kmalloc(sizeof(struct mesh_preq_queue), GFP_ATOMIC); 935 if (!preq_node) { 936 mhwmp_dbg(sdata, "could not allocate PREQ node\n"); 937 return; 938 } 939 940 spin_lock_bh(&ifmsh->mesh_preq_queue_lock); 941 if (ifmsh->preq_queue_len == MAX_PREQ_QUEUE_LEN) { 942 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock); 943 kfree(preq_node); 944 if (printk_ratelimit()) 945 mhwmp_dbg(sdata, "PREQ node queue full\n"); 946 return; 947 } 948 949 spin_lock(&mpath->state_lock); 950 if (mpath->flags & MESH_PATH_REQ_QUEUED) { 951 spin_unlock(&mpath->state_lock); 952 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock); 953 kfree(preq_node); 954 return; 955 } 956 957 memcpy(preq_node->dst, mpath->dst, ETH_ALEN); 958 preq_node->flags = flags; 959 960 mpath->flags |= MESH_PATH_REQ_QUEUED; 961 spin_unlock(&mpath->state_lock); 962 963 list_add_tail(&preq_node->list, &ifmsh->preq_queue.list); 964 ++ifmsh->preq_queue_len; 965 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock); 966 967 if (time_after(jiffies, ifmsh->last_preq + min_preq_int_jiff(sdata))) 968 ieee80211_queue_work(&sdata->local->hw, &sdata->work); 969 970 else if (time_before(jiffies, ifmsh->last_preq)) { 971 /* avoid long wait if did not send preqs for a long time 972 * and jiffies wrapped around 973 */ 974 ifmsh->last_preq = jiffies - min_preq_int_jiff(sdata) - 1; 975 ieee80211_queue_work(&sdata->local->hw, &sdata->work); 976 } else 977 mod_timer(&ifmsh->mesh_path_timer, ifmsh->last_preq + 978 min_preq_int_jiff(sdata)); 979 } 980 981 /** 982 * mesh_path_start_discovery - launch a path discovery from the PREQ queue 983 * 984 * @sdata: local mesh subif 985 */ 986 void mesh_path_start_discovery(struct ieee80211_sub_if_data *sdata) 987 { 988 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 989 struct mesh_preq_queue *preq_node; 990 struct mesh_path *mpath; 991 u8 ttl, target_flags = 0; 992 const u8 *da; 993 u32 lifetime; 994 995 spin_lock_bh(&ifmsh->mesh_preq_queue_lock); 996 if (!ifmsh->preq_queue_len || 997 time_before(jiffies, ifmsh->last_preq + 998 min_preq_int_jiff(sdata))) { 999 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock); 1000 return; 1001 } 1002 1003 preq_node = list_first_entry(&ifmsh->preq_queue.list, 1004 struct mesh_preq_queue, list); 1005 list_del(&preq_node->list); 1006 --ifmsh->preq_queue_len; 1007 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock); 1008 1009 rcu_read_lock(); 1010 mpath = mesh_path_lookup(sdata, preq_node->dst); 1011 if (!mpath) 1012 goto enddiscovery; 1013 1014 spin_lock_bh(&mpath->state_lock); 1015 if (mpath->flags & MESH_PATH_DELETED) { 1016 spin_unlock_bh(&mpath->state_lock); 1017 goto enddiscovery; 1018 } 1019 mpath->flags &= ~MESH_PATH_REQ_QUEUED; 1020 if (preq_node->flags & PREQ_Q_F_START) { 1021 if (mpath->flags & MESH_PATH_RESOLVING) { 1022 spin_unlock_bh(&mpath->state_lock); 1023 goto enddiscovery; 1024 } else { 1025 mpath->flags &= ~MESH_PATH_RESOLVED; 1026 mpath->flags |= MESH_PATH_RESOLVING; 1027 mpath->discovery_retries = 0; 1028 mpath->discovery_timeout = disc_timeout_jiff(sdata); 1029 } 1030 } else if (!(mpath->flags & MESH_PATH_RESOLVING) || 1031 mpath->flags & MESH_PATH_RESOLVED) { 1032 mpath->flags &= ~MESH_PATH_RESOLVING; 1033 spin_unlock_bh(&mpath->state_lock); 1034 goto enddiscovery; 1035 } 1036 1037 ifmsh->last_preq = jiffies; 1038 1039 if (time_after(jiffies, ifmsh->last_sn_update + 1040 net_traversal_jiffies(sdata)) || 1041 time_before(jiffies, ifmsh->last_sn_update)) { 1042 ++ifmsh->sn; 1043 sdata->u.mesh.last_sn_update = jiffies; 1044 } 1045 lifetime = default_lifetime(sdata); 1046 ttl = sdata->u.mesh.mshcfg.element_ttl; 1047 if (ttl == 0) { 1048 sdata->u.mesh.mshstats.dropped_frames_ttl++; 1049 spin_unlock_bh(&mpath->state_lock); 1050 goto enddiscovery; 1051 } 1052 1053 if (preq_node->flags & PREQ_Q_F_REFRESH) 1054 target_flags |= IEEE80211_PREQ_TO_FLAG; 1055 else 1056 target_flags &= ~IEEE80211_PREQ_TO_FLAG; 1057 1058 spin_unlock_bh(&mpath->state_lock); 1059 da = (mpath->is_root) ? mpath->rann_snd_addr : broadcast_addr; 1060 mesh_path_sel_frame_tx(MPATH_PREQ, 0, sdata->vif.addr, ifmsh->sn, 1061 target_flags, mpath->dst, mpath->sn, da, 0, 1062 ttl, lifetime, 0, ifmsh->preq_id++, sdata); 1063 mod_timer(&mpath->timer, jiffies + mpath->discovery_timeout); 1064 1065 enddiscovery: 1066 rcu_read_unlock(); 1067 kfree(preq_node); 1068 } 1069 1070 /** 1071 * mesh_nexthop_resolve - lookup next hop; conditionally start path discovery 1072 * 1073 * @skb: 802.11 frame to be sent 1074 * @sdata: network subif the frame will be sent through 1075 * 1076 * Lookup next hop for given skb and start path discovery if no 1077 * forwarding information is found. 1078 * 1079 * Returns: 0 if the next hop was found and -ENOENT if the frame was queued. 1080 * skb is freeed here if no mpath could be allocated. 1081 */ 1082 int mesh_nexthop_resolve(struct ieee80211_sub_if_data *sdata, 1083 struct sk_buff *skb) 1084 { 1085 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 1086 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 1087 struct mesh_path *mpath; 1088 struct sk_buff *skb_to_free = NULL; 1089 u8 *target_addr = hdr->addr3; 1090 int err = 0; 1091 1092 /* Nulls are only sent to peers for PS and should be pre-addressed */ 1093 if (ieee80211_is_qos_nullfunc(hdr->frame_control)) 1094 return 0; 1095 1096 rcu_read_lock(); 1097 err = mesh_nexthop_lookup(sdata, skb); 1098 if (!err) 1099 goto endlookup; 1100 1101 /* no nexthop found, start resolving */ 1102 mpath = mesh_path_lookup(sdata, target_addr); 1103 if (!mpath) { 1104 mpath = mesh_path_add(sdata, target_addr); 1105 if (IS_ERR(mpath)) { 1106 mesh_path_discard_frame(sdata, skb); 1107 err = PTR_ERR(mpath); 1108 goto endlookup; 1109 } 1110 } 1111 1112 if (!(mpath->flags & MESH_PATH_RESOLVING)) 1113 mesh_queue_preq(mpath, PREQ_Q_F_START); 1114 1115 if (skb_queue_len(&mpath->frame_queue) >= MESH_FRAME_QUEUE_LEN) 1116 skb_to_free = skb_dequeue(&mpath->frame_queue); 1117 1118 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING; 1119 ieee80211_set_qos_hdr(sdata, skb); 1120 skb_queue_tail(&mpath->frame_queue, skb); 1121 err = -ENOENT; 1122 if (skb_to_free) 1123 mesh_path_discard_frame(sdata, skb_to_free); 1124 1125 endlookup: 1126 rcu_read_unlock(); 1127 return err; 1128 } 1129 1130 /** 1131 * mesh_nexthop_lookup - put the appropriate next hop on a mesh frame. Calling 1132 * this function is considered "using" the associated mpath, so preempt a path 1133 * refresh if this mpath expires soon. 1134 * 1135 * @skb: 802.11 frame to be sent 1136 * @sdata: network subif the frame will be sent through 1137 * 1138 * Returns: 0 if the next hop was found. Nonzero otherwise. 1139 */ 1140 int mesh_nexthop_lookup(struct ieee80211_sub_if_data *sdata, 1141 struct sk_buff *skb) 1142 { 1143 struct mesh_path *mpath; 1144 struct sta_info *next_hop; 1145 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 1146 u8 *target_addr = hdr->addr3; 1147 int err = -ENOENT; 1148 1149 rcu_read_lock(); 1150 mpath = mesh_path_lookup(sdata, target_addr); 1151 1152 if (!mpath || !(mpath->flags & MESH_PATH_ACTIVE)) 1153 goto endlookup; 1154 1155 if (time_after(jiffies, 1156 mpath->exp_time - 1157 msecs_to_jiffies(sdata->u.mesh.mshcfg.path_refresh_time)) && 1158 ether_addr_equal(sdata->vif.addr, hdr->addr4) && 1159 !(mpath->flags & MESH_PATH_RESOLVING) && 1160 !(mpath->flags & MESH_PATH_FIXED)) 1161 mesh_queue_preq(mpath, PREQ_Q_F_START | PREQ_Q_F_REFRESH); 1162 1163 next_hop = rcu_dereference(mpath->next_hop); 1164 if (next_hop) { 1165 memcpy(hdr->addr1, next_hop->sta.addr, ETH_ALEN); 1166 memcpy(hdr->addr2, sdata->vif.addr, ETH_ALEN); 1167 ieee80211_mps_set_frame_flags(sdata, next_hop, hdr); 1168 err = 0; 1169 } 1170 1171 endlookup: 1172 rcu_read_unlock(); 1173 return err; 1174 } 1175 1176 void mesh_path_timer(unsigned long data) 1177 { 1178 struct mesh_path *mpath = (void *) data; 1179 struct ieee80211_sub_if_data *sdata = mpath->sdata; 1180 int ret; 1181 1182 if (sdata->local->quiescing) 1183 return; 1184 1185 spin_lock_bh(&mpath->state_lock); 1186 if (mpath->flags & MESH_PATH_RESOLVED || 1187 (!(mpath->flags & MESH_PATH_RESOLVING))) { 1188 mpath->flags &= ~(MESH_PATH_RESOLVING | MESH_PATH_RESOLVED); 1189 spin_unlock_bh(&mpath->state_lock); 1190 } else if (mpath->discovery_retries < max_preq_retries(sdata)) { 1191 ++mpath->discovery_retries; 1192 mpath->discovery_timeout *= 2; 1193 mpath->flags &= ~MESH_PATH_REQ_QUEUED; 1194 spin_unlock_bh(&mpath->state_lock); 1195 mesh_queue_preq(mpath, 0); 1196 } else { 1197 mpath->flags &= ~(MESH_PATH_RESOLVING | 1198 MESH_PATH_RESOLVED | 1199 MESH_PATH_REQ_QUEUED); 1200 mpath->exp_time = jiffies; 1201 spin_unlock_bh(&mpath->state_lock); 1202 if (!mpath->is_gate && mesh_gate_num(sdata) > 0) { 1203 ret = mesh_path_send_to_gates(mpath); 1204 if (ret) 1205 mhwmp_dbg(sdata, "no gate was reachable\n"); 1206 } else 1207 mesh_path_flush_pending(mpath); 1208 } 1209 } 1210 1211 void mesh_path_tx_root_frame(struct ieee80211_sub_if_data *sdata) 1212 { 1213 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 1214 u32 interval = ifmsh->mshcfg.dot11MeshHWMPRannInterval; 1215 u8 flags, target_flags = 0; 1216 1217 flags = (ifmsh->mshcfg.dot11MeshGateAnnouncementProtocol) 1218 ? RANN_FLAG_IS_GATE : 0; 1219 1220 switch (ifmsh->mshcfg.dot11MeshHWMPRootMode) { 1221 case IEEE80211_PROACTIVE_RANN: 1222 mesh_path_sel_frame_tx(MPATH_RANN, flags, sdata->vif.addr, 1223 ++ifmsh->sn, 0, NULL, 0, broadcast_addr, 1224 0, ifmsh->mshcfg.element_ttl, 1225 interval, 0, 0, sdata); 1226 break; 1227 case IEEE80211_PROACTIVE_PREQ_WITH_PREP: 1228 flags |= IEEE80211_PREQ_PROACTIVE_PREP_FLAG; 1229 case IEEE80211_PROACTIVE_PREQ_NO_PREP: 1230 interval = ifmsh->mshcfg.dot11MeshHWMPactivePathToRootTimeout; 1231 target_flags |= IEEE80211_PREQ_TO_FLAG | 1232 IEEE80211_PREQ_USN_FLAG; 1233 mesh_path_sel_frame_tx(MPATH_PREQ, flags, sdata->vif.addr, 1234 ++ifmsh->sn, target_flags, 1235 (u8 *) broadcast_addr, 0, broadcast_addr, 1236 0, ifmsh->mshcfg.element_ttl, interval, 1237 0, ifmsh->preq_id++, sdata); 1238 break; 1239 default: 1240 mhwmp_dbg(sdata, "Proactive mechanism not supported\n"); 1241 return; 1242 } 1243 } 1244