1 // SPDX-License-Identifier: GPL-2.0-only
3 * Copyright (c) 2008, 2009 open80211s Ltd.
4 * Copyright (C) 2019, 2021-2022 Intel Corporation
5 * Author: Luis Carlos Cobo <luisca@cozybit.com>
8 #include <linux/slab.h>
9 #include <linux/etherdevice.h>
10 #include <asm/unaligned.h>
14 #define TEST_FRAME_LEN 8192
15 #define MAX_METRIC 0xffffffff
17 #define LINK_FAIL_THRESH 95
19 #define MAX_PREQ_QUEUE_LEN 64
21 static void mesh_queue_preq(struct mesh_path *, u8);
23 static inline u32 u32_field_get(const u8 *preq_elem, int offset, bool ae)
27 return get_unaligned_le32(preq_elem + offset);
30 static inline u16 u16_field_get(const u8 *preq_elem, int offset, bool ae)
34 return get_unaligned_le16(preq_elem + offset);
37 /* HWMP IE processing macros */
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))
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)
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)
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
74 static inline u32 SN_DELTA(u32 x, u32 y)
76 return x >= y ? x - y : y - x;
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)
91 enum mpath_frame_type {
98 static const u8 broadcast_addr[ETH_ALEN] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
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)
108 struct ieee80211_local *local = sdata->local;
110 struct ieee80211_mgmt *mgmt;
112 int hdr_len = offsetofend(struct ieee80211_mgmt,
113 u.action.u.mesh_action);
115 skb = dev_alloc_skb(local->tx_headroom +
117 2 + 37); /* max HWMP IE */
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);
125 memcpy(mgmt->da, da, ETH_ALEN);
126 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
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;
135 mhwmp_dbg(sdata, "sending PREQ to %pM\n", target);
137 pos = skb_put(skb, 2 + ie_len);
138 *pos++ = WLAN_EID_PREQ;
141 mhwmp_dbg(sdata, "sending PREP to %pM\n", orig_addr);
143 pos = skb_put(skb, 2 + ie_len);
144 *pos++ = WLAN_EID_PREP;
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;
160 if (action == MPATH_PREP) {
161 memcpy(pos, target, ETH_ALEN);
163 put_unaligned_le32(target_sn, pos);
166 if (action == MPATH_PREQ) {
167 put_unaligned_le32(preq_id, pos);
170 memcpy(pos, orig_addr, ETH_ALEN);
172 put_unaligned_le32(orig_sn, pos);
175 put_unaligned_le32(lifetime, pos); /* interval for RANN */
177 put_unaligned_le32(metric, pos);
179 if (action == MPATH_PREQ) {
180 *pos++ = 1; /* destination count */
181 *pos++ = target_flags;
182 memcpy(pos, target, ETH_ALEN);
184 put_unaligned_le32(target_sn, pos);
186 } else if (action == MPATH_PREP) {
187 memcpy(pos, orig_addr, ETH_ALEN);
189 put_unaligned_le32(orig_sn, pos);
193 ieee80211_tx_skb(sdata, skb);
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,
203 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
204 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
206 skb_reset_mac_header(skb);
207 skb_reset_network_header(skb);
208 skb_reset_transport_header(skb);
210 /* Send all internal mgmt frames on VO. Accordingly set TID to 7. */
211 skb_set_queue_mapping(skb, IEEE80211_AC_VO);
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);
221 * mesh_path_error_tx - Sends a PERR mesh management frame
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
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.
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)
238 struct ieee80211_local *local = sdata->local;
240 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
241 struct ieee80211_mgmt *mgmt;
243 int hdr_len = offsetofend(struct ieee80211_mgmt,
244 u.action.u.mesh_action);
246 if (time_before(jiffies, ifmsh->next_perr))
249 skb = dev_alloc_skb(local->tx_headroom +
250 IEEE80211_ENCRYPT_HEADROOM +
251 IEEE80211_ENCRYPT_TAILROOM +
253 2 + 15 /* PERR IE */);
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);
261 memcpy(mgmt->da, ra, ETH_ALEN);
262 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
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;
269 pos = skb_put(skb, 2 + ie_len);
270 *pos++ = WLAN_EID_PERR;
274 /* number of destinations */
276 /* Flags field has AE bit only as defined in
277 * sec 8.4.2.117 IEEE802.11-2012
281 memcpy(pos, target, ETH_ALEN);
283 put_unaligned_le32(target_sn, pos);
285 put_unaligned_le16(target_rcode, pos);
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);
295 void ieee80211s_update_metric(struct ieee80211_local *local,
296 struct sta_info *sta,
297 struct ieee80211_tx_status *st)
299 struct ieee80211_tx_info *txinfo = st->info;
301 struct rate_info rinfo;
303 failed = !(txinfo->flags & IEEE80211_TX_STAT_ACK);
305 /* moving average, scaled to 100.
306 * feed failure as 100 and success as 0
308 ewma_mesh_fail_avg_add(&sta->mesh->fail_avg, failed * 100);
309 if (ewma_mesh_fail_avg_read(&sta->mesh->fail_avg) >
311 mesh_plink_broken(sta);
313 /* use rate info set by the driver directly if present */
315 rinfo = sta->deflink.tx_stats.last_rate_info;
317 sta_set_rate_info_tx(sta, &sta->deflink.tx_stats.last_rate, &rinfo);
319 ewma_mesh_tx_rate_avg_add(&sta->mesh->tx_rate_avg,
320 cfg80211_calculate_bitrate(&rinfo));
323 u32 airtime_link_metric_get(struct ieee80211_local *local,
324 struct sta_info *sta)
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;
331 u32 tx_time, estimated_retx;
333 unsigned long fail_avg =
334 ewma_mesh_fail_avg_read(&sta->mesh->fail_avg);
336 if (sta->mesh->plink_state != NL80211_PLINK_ESTAB)
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
344 rate = DIV_ROUND_UP(sta_get_expected_throughput(sta), 100);
349 if (fail_avg > LINK_FAIL_THRESH)
352 rate = ewma_mesh_tx_rate_avg_read(&sta->mesh->tx_rate_avg);
356 err = (fail_avg << ARITH_SHIFT) / 100;
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.
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);
369 * hwmp_route_info_get - Update routing info to originator and transmitter
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
376 * This function updates the path routing information to the originator and the
377 * transmitter of a HWMP PREQ or PREP frame.
379 * Returns: metric to frame originator or 0 if the frame should not be further
382 * Notes: this function is the only place (besides user-provided info) where
383 * path routing information is updated.
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)
389 struct ieee80211_local *local = sdata->local;
390 struct mesh_path *mpath;
391 struct sta_info *sta;
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;
401 sta = sta_info_get(sdata, mgmt->sa);
407 last_hop_metric = airtime_link_metric_get(local, sta);
408 /* Update and check originator routing info */
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;
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.
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;
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);
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.
447 mpath = mesh_path_lookup(sdata, orig_addr);
449 spin_lock_bh(&mpath->state_lock);
450 if (mpath->flags & MESH_PATH_FIXED)
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) !=
458 mult_frac(new_metric, 10, 9) :
459 new_metric) >= mpath->metric)) {
463 } else if (!(mpath->flags & MESH_PATH_ACTIVE)) {
464 bool have_sn, newer_sn, bounced;
466 have_sn = mpath->flags & MESH_PATH_SN_VALID;
467 newer_sn = have_sn && SN_GT(orig_sn, mpath->sn);
469 (SN_DELTA(orig_sn, mpath->sn) >
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 */;
485 mpath = mesh_path_add(sdata, orig_addr);
490 spin_lock_bh(&mpath->state_lock);
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;
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
513 spin_unlock_bh(&mpath->state_lock);
516 /* Update and check transmitter routing info */
518 if (ether_addr_equal(orig_addr, ta))
523 mpath = mesh_path_lookup(sdata, ta);
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)))
533 mpath = mesh_path_add(sdata, ta);
538 spin_lock_bh(&mpath->state_lock);
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);
556 spin_unlock_bh(&mpath->state_lock);
561 return process ? new_metric : 0;
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)
568 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
569 struct mesh_path *mpath = NULL;
570 const u8 *target_addr, *orig_addr;
572 u8 target_flags, ttl, flags;
573 u32 orig_sn, target_sn, lifetime, target_metric = 0;
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);
588 mhwmp_dbg(sdata, "received PREQ from %pM\n", orig_addr);
590 if (ether_addr_equal(target_addr, sdata->vif.addr)) {
591 mhwmp_dbg(sdata, "PREQ is for us\n");
596 if (SN_GT(target_sn, ifmsh->sn))
597 ifmsh->sn = target_sn;
599 if (time_after(jiffies, ifmsh->last_sn_update +
600 net_traversal_jiffies(sdata)) ||
601 time_before(jiffies, ifmsh->last_sn_update)) {
603 ifmsh->last_sn_update = jiffies;
605 target_sn = ifmsh->sn;
606 } else if (is_broadcast_ether_addr(target_addr) &&
607 (target_flags & IEEE80211_PREQ_TO_FLAG)) {
609 mpath = mesh_path_lookup(sdata, orig_addr);
611 if (flags & IEEE80211_PREQ_PROACTIVE_PREP_FLAG) {
613 target_addr = sdata->vif.addr;
614 target_sn = ++ifmsh->sn;
616 ifmsh->last_sn_update = jiffies;
619 mesh_path_add_gate(mpath);
624 mpath = mesh_path_lookup(sdata, target_addr);
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)) {
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;
643 lifetime = PREQ_IE_LIFETIME(preq_elem);
644 ttl = ifmsh->mshcfg.element_ttl;
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,
653 ifmsh->mshstats.dropped_frames_ttl++;
657 if (forward && ifmsh->mshcfg.dot11MeshForwarding) {
661 ttl = PREQ_IE_TTL(preq_elem);
662 lifetime = PREQ_IE_LIFETIME(preq_elem);
664 ifmsh->mshstats.dropped_frames_ttl++;
667 mhwmp_dbg(sdata, "forwarding the PREQ from %pM\n", orig_addr);
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;
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);
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++;
686 ifmsh->mshstats.fwded_mcast++;
687 ifmsh->mshstats.fwded_frames++;
692 static inline struct sta_info *
693 next_hop_deref_protected(struct mesh_path *mpath)
695 return rcu_dereference_protected(mpath->next_hop,
696 lockdep_is_held(&mpath->state_lock));
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)
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;
711 mhwmp_dbg(sdata, "received PREP from %pM\n",
712 PREP_IE_TARGET_ADDR(prep_elem));
714 orig_addr = PREP_IE_ORIG_ADDR(prep_elem);
715 if (ether_addr_equal(orig_addr, sdata->vif.addr))
716 /* destination, no forwarding required */
719 if (!ifmsh->mshcfg.dot11MeshForwarding)
722 ttl = PREP_IE_TTL(prep_elem);
724 sdata->u.mesh.mshstats.dropped_frames_ttl++;
729 mpath = mesh_path_lookup(sdata, orig_addr);
731 spin_lock_bh(&mpath->state_lock);
734 if (!(mpath->flags & MESH_PATH_ACTIVE)) {
735 spin_unlock_bh(&mpath->state_lock);
738 memcpy(next_hop, next_hop_deref_protected(mpath)->sta.addr, ETH_ALEN);
739 spin_unlock_bh(&mpath->state_lock);
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);
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);
753 sdata->u.mesh.mshstats.fwded_unicast++;
754 sdata->u.mesh.mshstats.fwded_frames++;
759 sdata->u.mesh.mshstats.dropped_frames_no_route++;
762 static void hwmp_perr_frame_process(struct ieee80211_sub_if_data *sdata,
763 struct ieee80211_mgmt *mgmt,
766 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
767 struct mesh_path *mpath;
769 const u8 *ta, *target_addr;
774 ttl = PERR_IE_TTL(perr_elem);
776 ifmsh->mshstats.dropped_frames_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);
785 mpath = mesh_path_lookup(sdata, target_addr);
787 struct sta_info *sta;
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;
798 mpath->sn = target_sn;
801 spin_unlock_bh(&mpath->state_lock);
802 if (!ifmsh->mshcfg.dot11MeshForwarding)
804 mesh_path_error_tx(sdata, ttl, target_addr,
805 target_sn, target_rcode,
808 spin_unlock_bh(&mpath->state_lock);
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)
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;
824 u32 orig_sn, new_metric, orig_metric, last_hop_metric, interval;
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;
835 orig_metric = le32_to_cpu(rann->rann_metric);
837 /* Ignore our own RANNs */
838 if (ether_addr_equal(orig_addr, sdata->vif.addr))
842 "received RANN from %pM via neighbour %pM (is_gate=%d)\n",
843 orig_addr, mgmt->sa, root_is_gate);
846 sta = sta_info_get(sdata, mgmt->sa);
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;
857 mpath = mesh_path_lookup(sdata, orig_addr);
859 mpath = mesh_path_add(sdata, orig_addr);
862 sdata->u.mesh.mshstats.dropped_frames_no_route++;
867 if (!(SN_LT(mpath->sn, orig_sn)) &&
868 !(mpath->sn == orig_sn && new_metric < mpath->rann_metric)) {
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)) {
879 "time to refresh root mpath %pM\n",
881 mesh_queue_preq(mpath, PREQ_Q_F_START | PREQ_Q_F_REFRESH);
882 mpath->last_preq_to_root = jiffies;
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);
893 mesh_path_add_gate(mpath);
896 ifmsh->mshstats.dropped_frames_ttl++;
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);
913 void mesh_rx_path_sel_frame(struct ieee80211_sub_if_data *sdata,
914 struct ieee80211_mgmt *mgmt, size_t len)
916 struct ieee802_11_elems *elems;
919 struct sta_info *sta;
921 /* need action_code */
922 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
926 sta = sta_info_get(sdata, mgmt->sa);
927 if (!sta || sta->mesh->plink_state != NL80211_PLINK_ESTAB) {
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);
940 if (elems->preq_len != 37)
941 /* Right now we support just 1 destination and no AE */
943 path_metric = hwmp_route_info_get(sdata, mgmt, elems->preq,
946 hwmp_preq_frame_process(sdata, mgmt, elems->preq,
950 if (elems->prep_len != 31)
951 /* Right now we support no AE */
953 path_metric = hwmp_route_info_get(sdata, mgmt, elems->prep,
956 hwmp_prep_frame_process(sdata, mgmt, elems->prep,
960 if (elems->perr_len != 15)
961 /* Right now we support only one destination per PERR */
963 hwmp_perr_frame_process(sdata, mgmt, elems->perr);
966 hwmp_rann_frame_process(sdata, mgmt, elems->rann);
972 * mesh_queue_preq - queue a PREQ to a given destination
974 * @mpath: mesh path to discover
975 * @flags: special attributes of the PREQ to be sent
977 * Locking: the function must be called from within a rcu read lock block.
980 static void mesh_queue_preq(struct mesh_path *mpath, u8 flags)
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;
986 preq_node = kmalloc(sizeof(struct mesh_preq_queue), GFP_ATOMIC);
988 mhwmp_dbg(sdata, "could not allocate PREQ node\n");
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);
996 if (printk_ratelimit())
997 mhwmp_dbg(sdata, "PREQ node queue full\n");
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);
1009 memcpy(preq_node->dst, mpath->dst, ETH_ALEN);
1010 preq_node->flags = flags;
1012 mpath->flags |= MESH_PATH_REQ_QUEUED;
1013 spin_unlock(&mpath->state_lock);
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);
1019 if (time_after(jiffies, ifmsh->last_preq + min_preq_int_jiff(sdata)))
1020 ieee80211_queue_work(&sdata->local->hw, &sdata->work);
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
1026 ifmsh->last_preq = jiffies - min_preq_int_jiff(sdata) - 1;
1027 ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1029 mod_timer(&ifmsh->mesh_path_timer, ifmsh->last_preq +
1030 min_preq_int_jiff(sdata));
1034 * mesh_path_start_discovery - launch a path discovery from the PREQ queue
1036 * @sdata: local mesh subif
1038 void mesh_path_start_discovery(struct ieee80211_sub_if_data *sdata)
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;
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);
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);
1062 mpath = mesh_path_lookup(sdata, preq_node->dst);
1066 spin_lock_bh(&mpath->state_lock);
1067 if (mpath->flags & (MESH_PATH_DELETED | MESH_PATH_FIXED)) {
1068 spin_unlock_bh(&mpath->state_lock);
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);
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);
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);
1089 ifmsh->last_preq = jiffies;
1091 if (time_after(jiffies, ifmsh->last_sn_update +
1092 net_traversal_jiffies(sdata)) ||
1093 time_before(jiffies, ifmsh->last_sn_update)) {
1095 sdata->u.mesh.last_sn_update = jiffies;
1097 lifetime = default_lifetime(sdata);
1098 ttl = sdata->u.mesh.mshcfg.element_ttl;
1100 sdata->u.mesh.mshstats.dropped_frames_ttl++;
1101 spin_unlock_bh(&mpath->state_lock);
1105 if (preq_node->flags & PREQ_Q_F_REFRESH)
1106 target_flags |= IEEE80211_PREQ_TO_FLAG;
1108 target_flags &= ~IEEE80211_PREQ_TO_FLAG;
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);
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);
1127 * mesh_nexthop_resolve - lookup next hop; conditionally start path discovery
1129 * @skb: 802.11 frame to be sent
1130 * @sdata: network subif the frame will be sent through
1132 * Lookup next hop for given skb and start path discovery if no
1133 * forwarding information is found.
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.
1138 int mesh_nexthop_resolve(struct ieee80211_sub_if_data *sdata,
1139 struct sk_buff *skb)
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;
1147 /* Nulls are only sent to peers for PS and should be pre-addressed */
1148 if (ieee80211_is_qos_nullfunc(hdr->frame_control))
1151 /* Allow injected packets to bypass mesh routing */
1152 if (info->control.flags & IEEE80211_TX_CTRL_SKIP_MPATH_LOOKUP)
1155 if (!mesh_nexthop_lookup(sdata, skb))
1158 /* no nexthop found, start resolving */
1159 mpath = mesh_path_lookup(sdata, target_addr);
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);
1168 if (!(mpath->flags & MESH_PATH_RESOLVING) &&
1169 mesh_path_sel_is_hwmp(sdata))
1170 mesh_queue_preq(mpath, PREQ_Q_F_START);
1172 if (skb_queue_len(&mpath->frame_queue) >= MESH_FRAME_QUEUE_LEN)
1173 skb_to_free = skb_dequeue(&mpath->frame_queue);
1175 info->control.flags |= IEEE80211_TX_INTCFL_NEED_TXPROCESSING;
1176 ieee80211_set_qos_hdr(sdata, skb);
1177 skb_queue_tail(&mpath->frame_queue, skb);
1179 mesh_path_discard_frame(sdata, skb_to_free);
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
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.
1193 * Returns: 0 if the next hop was found and -ENOENT otherwise.
1195 static int mesh_nexthop_lookup_nolearn(struct ieee80211_sub_if_data *sdata,
1196 struct sk_buff *skb)
1198 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1199 struct sta_info *sta;
1201 if (is_multicast_ether_addr(hdr->addr1))
1205 sta = sta_info_get(sdata, hdr->addr3);
1207 if (!sta || sta->mesh->plink_state != NL80211_PLINK_ESTAB) {
1213 memcpy(hdr->addr1, hdr->addr3, ETH_ALEN);
1214 memcpy(hdr->addr2, sdata->vif.addr, ETH_ALEN);
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.
1223 * @skb: 802.11 frame to be sent
1224 * @sdata: network subif the frame will be sent through
1226 * Returns: 0 if the next hop was found. Nonzero otherwise.
1228 int mesh_nexthop_lookup(struct ieee80211_sub_if_data *sdata,
1229 struct sk_buff *skb)
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;
1237 if (ifmsh->mshcfg.dot11MeshNolearn &&
1238 !mesh_nexthop_lookup_nolearn(sdata, skb))
1241 mpath = mesh_path_lookup(sdata, target_addr);
1242 if (!mpath || !(mpath->flags & MESH_PATH_ACTIVE))
1245 if (time_after(jiffies,
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);
1253 next_hop = rcu_dereference(mpath->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);
1264 void mesh_path_timer(struct timer_list *t)
1266 struct mesh_path *mpath = from_timer(mpath, t, timer);
1267 struct ieee80211_sub_if_data *sdata = mpath->sdata;
1270 if (sdata->local->quiescing)
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);
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);
1293 mhwmp_dbg(sdata, "no gate was reachable\n");
1295 mesh_path_flush_pending(mpath);
1299 void mesh_path_tx_root_frame(struct ieee80211_sub_if_data *sdata)
1301 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1302 u32 interval = ifmsh->mshcfg.dot11MeshHWMPRannInterval;
1303 u8 flags, target_flags = 0;
1305 flags = (ifmsh->mshcfg.dot11MeshGateAnnouncementProtocol)
1306 ? RANN_FLAG_IS_GATE : 0;
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);
1315 case IEEE80211_PROACTIVE_PREQ_WITH_PREP:
1316 flags |= IEEE80211_PREQ_PROACTIVE_PREP_FLAG;
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);
1329 mhwmp_dbg(sdata, "Proactive mechanism not supported\n");