2 * Copyright (c) 2008, 2009 open80211s Ltd.
3 * Author: Luis Carlos Cobo <luisca@cozybit.com>
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.
10 #include <linux/slab.h>
11 #include <linux/etherdevice.h>
12 #include <asm/unaligned.h>
16 #define TEST_FRAME_LEN 8192
17 #define MAX_METRIC 0xffffffff
20 #define MAX_PREQ_QUEUE_LEN 64
22 static void mesh_queue_preq(struct mesh_path *, u8);
24 static inline u32 u32_field_get(const u8 *preq_elem, int offset, bool ae)
28 return get_unaligned_le32(preq_elem + offset);
31 static inline u16 u16_field_get(const u8 *preq_elem, int offset, bool ae)
35 return get_unaligned_le16(preq_elem + offset);
38 /* HWMP IE processing macros */
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))
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)
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)
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
75 static inline u32 SN_DELTA(u32 x, u32 y)
77 return x >= y ? x - y : y - x;
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)
92 enum mpath_frame_type {
99 static const u8 broadcast_addr[ETH_ALEN] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
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)
109 struct ieee80211_local *local = sdata->local;
111 struct ieee80211_mgmt *mgmt;
113 int hdr_len = offsetof(struct ieee80211_mgmt, u.action.u.mesh_action) +
114 sizeof(mgmt->u.action.u.mesh_action);
116 skb = dev_alloc_skb(local->tx_headroom +
118 2 + 37); /* max HWMP IE */
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);
127 memcpy(mgmt->da, da, ETH_ALEN);
128 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
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;
137 mhwmp_dbg(sdata, "sending PREQ to %pM\n", target);
139 pos = skb_put(skb, 2 + ie_len);
140 *pos++ = WLAN_EID_PREQ;
143 mhwmp_dbg(sdata, "sending PREP to %pM\n", orig_addr);
145 pos = skb_put(skb, 2 + ie_len);
146 *pos++ = WLAN_EID_PREP;
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;
162 if (action == MPATH_PREP) {
163 memcpy(pos, target, ETH_ALEN);
165 put_unaligned_le32(target_sn, pos);
168 if (action == MPATH_PREQ) {
169 put_unaligned_le32(preq_id, pos);
172 memcpy(pos, orig_addr, ETH_ALEN);
174 put_unaligned_le32(orig_sn, pos);
177 put_unaligned_le32(lifetime, pos); /* interval for RANN */
179 put_unaligned_le32(metric, pos);
181 if (action == MPATH_PREQ) {
182 *pos++ = 1; /* destination count */
183 *pos++ = target_flags;
184 memcpy(pos, target, ETH_ALEN);
186 put_unaligned_le32(target_sn, pos);
188 } else if (action == MPATH_PREP) {
189 memcpy(pos, orig_addr, ETH_ALEN);
191 put_unaligned_le32(orig_sn, pos);
195 ieee80211_tx_skb(sdata, skb);
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,
205 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
206 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
208 skb_reset_mac_header(skb);
209 skb_reset_network_header(skb);
210 skb_reset_transport_header(skb);
212 /* Send all internal mgmt frames on VO. Accordingly set TID to 7. */
213 skb_set_queue_mapping(skb, IEEE80211_AC_VO);
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);
223 * mesh_path_error_tx - Sends a PERR mesh management frame
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
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.
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)
240 struct ieee80211_local *local = sdata->local;
242 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
243 struct ieee80211_mgmt *mgmt;
245 int hdr_len = offsetof(struct ieee80211_mgmt, u.action.u.mesh_action) +
246 sizeof(mgmt->u.action.u.mesh_action);
248 if (time_before(jiffies, ifmsh->next_perr))
251 skb = dev_alloc_skb(local->tx_headroom +
252 sdata->encrypt_headroom +
253 IEEE80211_ENCRYPT_TAILROOM +
255 2 + 15 /* PERR IE */);
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);
264 memcpy(mgmt->da, ra, ETH_ALEN);
265 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
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;
272 pos = skb_put(skb, 2 + ie_len);
273 *pos++ = WLAN_EID_PERR;
277 /* number of destinations */
279 /* Flags field has AE bit only as defined in
280 * sec 8.4.2.117 IEEE802.11-2012
284 memcpy(pos, target, ETH_ALEN);
286 put_unaligned_le32(target_sn, pos);
288 put_unaligned_le16(target_rcode, pos);
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);
298 void ieee80211s_update_metric(struct ieee80211_local *local,
299 struct sta_info *sta, struct sk_buff *skb)
301 struct ieee80211_tx_info *txinfo = IEEE80211_SKB_CB(skb);
302 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
305 if (!ieee80211_is_data(hdr->frame_control))
308 failed = !(txinfo->flags & IEEE80211_TX_STAT_ACK);
310 /* moving average, scaled to 100.
311 * feed failure as 100 and success as 0
313 ewma_mesh_fail_avg_add(&sta->mesh->fail_avg, failed * 100);
314 if (ewma_mesh_fail_avg_read(&sta->mesh->fail_avg) > 95)
315 mesh_plink_broken(sta);
318 static u32 airtime_link_metric_get(struct ieee80211_local *local,
319 struct sta_info *sta)
321 struct rate_info rinfo;
322 /* This should be adjusted for each device */
323 int device_constant = 1 << ARITH_SHIFT;
324 int test_frame_len = TEST_FRAME_LEN << ARITH_SHIFT;
325 int s_unit = 1 << ARITH_SHIFT;
327 u32 tx_time, estimated_retx;
329 unsigned long fail_avg =
330 ewma_mesh_fail_avg_read(&sta->mesh->fail_avg);
332 /* Try to get rate based on HW/SW RC algorithm.
333 * Rate is returned in units of Kbps, correct this
334 * to comply with airtime calculation units
335 * Round up in case we get rate < 100Kbps
337 rate = DIV_ROUND_UP(sta_get_expected_throughput(sta), 100);
345 sta_set_rate_info_tx(sta, &sta->tx_stats.last_rate, &rinfo);
346 rate = cfg80211_calculate_bitrate(&rinfo);
350 err = (fail_avg << ARITH_SHIFT) / 100;
353 /* bitrate is in units of 100 Kbps, while we need rate in units of
354 * 1Mbps. This will be corrected on tx_time computation.
356 tx_time = (device_constant + 10 * test_frame_len / rate);
357 estimated_retx = ((1 << (2 * ARITH_SHIFT)) / (s_unit - err));
358 result = (tx_time * estimated_retx) >> (2 * ARITH_SHIFT);
363 * hwmp_route_info_get - Update routing info to originator and transmitter
365 * @sdata: local mesh subif
366 * @mgmt: mesh management frame
367 * @hwmp_ie: hwmp information element (PREP or PREQ)
368 * @action: type of hwmp ie
370 * This function updates the path routing information to the originator and the
371 * transmitter of a HWMP PREQ or PREP frame.
373 * Returns: metric to frame originator or 0 if the frame should not be further
376 * Notes: this function is the only place (besides user-provided info) where
377 * path routing information is updated.
379 static u32 hwmp_route_info_get(struct ieee80211_sub_if_data *sdata,
380 struct ieee80211_mgmt *mgmt,
381 const u8 *hwmp_ie, enum mpath_frame_type action)
383 struct ieee80211_local *local = sdata->local;
384 struct mesh_path *mpath;
385 struct sta_info *sta;
387 const u8 *orig_addr, *ta;
388 u32 orig_sn, orig_metric;
389 unsigned long orig_lifetime, exp_time;
390 u32 last_hop_metric, new_metric;
394 sta = sta_info_get(sdata, mgmt->sa);
400 last_hop_metric = airtime_link_metric_get(local, sta);
401 /* Update and check originator routing info */
406 orig_addr = PREQ_IE_ORIG_ADDR(hwmp_ie);
407 orig_sn = PREQ_IE_ORIG_SN(hwmp_ie);
408 orig_lifetime = PREQ_IE_LIFETIME(hwmp_ie);
409 orig_metric = PREQ_IE_METRIC(hwmp_ie);
412 /* Originator here refers to the MP that was the target in the
413 * Path Request. We divert from the nomenclature in the draft
414 * so that we can easily use a single function to gather path
415 * information from both PREQ and PREP frames.
417 orig_addr = PREP_IE_TARGET_ADDR(hwmp_ie);
418 orig_sn = PREP_IE_TARGET_SN(hwmp_ie);
419 orig_lifetime = PREP_IE_LIFETIME(hwmp_ie);
420 orig_metric = PREP_IE_METRIC(hwmp_ie);
426 new_metric = orig_metric + last_hop_metric;
427 if (new_metric < orig_metric)
428 new_metric = MAX_METRIC;
429 exp_time = TU_TO_EXP_TIME(orig_lifetime);
431 if (ether_addr_equal(orig_addr, sdata->vif.addr)) {
432 /* This MP is the originator, we are not interested in this
433 * frame, except for updating transmitter's path info.
438 mpath = mesh_path_lookup(sdata, orig_addr);
440 spin_lock_bh(&mpath->state_lock);
441 if (mpath->flags & MESH_PATH_FIXED)
443 else if ((mpath->flags & MESH_PATH_ACTIVE) &&
444 (mpath->flags & MESH_PATH_SN_VALID)) {
445 if (SN_GT(mpath->sn, orig_sn) ||
446 (mpath->sn == orig_sn &&
447 new_metric >= mpath->metric)) {
451 } else if (!(mpath->flags & MESH_PATH_ACTIVE)) {
452 bool have_sn, newer_sn, bounced;
454 have_sn = mpath->flags & MESH_PATH_SN_VALID;
455 newer_sn = have_sn && SN_GT(orig_sn, mpath->sn);
457 (SN_DELTA(orig_sn, mpath->sn) >
460 if (!have_sn || newer_sn) {
461 /* if SN is newer than what we had
462 * then we can take it */;
463 } else if (bounced) {
464 /* if SN is way different than what
465 * we had then assume the other side
466 * rebooted or restarted */;
473 mpath = mesh_path_add(sdata, orig_addr);
478 spin_lock_bh(&mpath->state_lock);
482 mesh_path_assign_nexthop(mpath, sta);
483 mpath->flags |= MESH_PATH_SN_VALID;
484 mpath->metric = new_metric;
486 mpath->exp_time = time_after(mpath->exp_time, exp_time)
487 ? mpath->exp_time : exp_time;
488 mesh_path_activate(mpath);
489 spin_unlock_bh(&mpath->state_lock);
490 ewma_mesh_fail_avg_init(&sta->mesh->fail_avg);
491 /* init it at a low value - 0 start is tricky */
492 ewma_mesh_fail_avg_add(&sta->mesh->fail_avg, 1);
493 mesh_path_tx_pending(mpath);
494 /* draft says preq_id should be saved to, but there does
495 * not seem to be any use for it, skipping by now
498 spin_unlock_bh(&mpath->state_lock);
501 /* Update and check transmitter routing info */
503 if (ether_addr_equal(orig_addr, ta))
508 mpath = mesh_path_lookup(sdata, ta);
510 spin_lock_bh(&mpath->state_lock);
511 if ((mpath->flags & MESH_PATH_FIXED) ||
512 ((mpath->flags & MESH_PATH_ACTIVE) &&
513 (last_hop_metric > mpath->metric)))
516 mpath = mesh_path_add(sdata, ta);
521 spin_lock_bh(&mpath->state_lock);
525 mesh_path_assign_nexthop(mpath, sta);
526 mpath->metric = last_hop_metric;
527 mpath->exp_time = time_after(mpath->exp_time, exp_time)
528 ? mpath->exp_time : exp_time;
529 mesh_path_activate(mpath);
530 spin_unlock_bh(&mpath->state_lock);
531 ewma_mesh_fail_avg_init(&sta->mesh->fail_avg);
532 /* init it at a low value - 0 start is tricky */
533 ewma_mesh_fail_avg_add(&sta->mesh->fail_avg, 1);
534 mesh_path_tx_pending(mpath);
536 spin_unlock_bh(&mpath->state_lock);
541 return process ? new_metric : 0;
544 static void hwmp_preq_frame_process(struct ieee80211_sub_if_data *sdata,
545 struct ieee80211_mgmt *mgmt,
546 const u8 *preq_elem, u32 orig_metric)
548 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
549 struct mesh_path *mpath = NULL;
550 const u8 *target_addr, *orig_addr;
552 u8 target_flags, ttl, flags;
553 u32 orig_sn, target_sn, lifetime, target_metric = 0;
558 /* Update target SN, if present */
559 target_addr = PREQ_IE_TARGET_ADDR(preq_elem);
560 orig_addr = PREQ_IE_ORIG_ADDR(preq_elem);
561 target_sn = PREQ_IE_TARGET_SN(preq_elem);
562 orig_sn = PREQ_IE_ORIG_SN(preq_elem);
563 target_flags = PREQ_IE_TARGET_F(preq_elem);
564 /* Proactive PREQ gate announcements */
565 flags = PREQ_IE_FLAGS(preq_elem);
566 root_is_gate = !!(flags & RANN_FLAG_IS_GATE);
568 mhwmp_dbg(sdata, "received PREQ from %pM\n", orig_addr);
570 if (ether_addr_equal(target_addr, sdata->vif.addr)) {
571 mhwmp_dbg(sdata, "PREQ is for us\n");
575 if (time_after(jiffies, ifmsh->last_sn_update +
576 net_traversal_jiffies(sdata)) ||
577 time_before(jiffies, ifmsh->last_sn_update)) {
579 ifmsh->last_sn_update = jiffies;
581 target_sn = ifmsh->sn;
582 } else if (is_broadcast_ether_addr(target_addr) &&
583 (target_flags & IEEE80211_PREQ_TO_FLAG)) {
585 mpath = mesh_path_lookup(sdata, orig_addr);
587 if (flags & IEEE80211_PREQ_PROACTIVE_PREP_FLAG) {
589 target_addr = sdata->vif.addr;
590 target_sn = ++ifmsh->sn;
592 ifmsh->last_sn_update = jiffies;
595 mesh_path_add_gate(mpath);
600 mpath = mesh_path_lookup(sdata, target_addr);
602 if ((!(mpath->flags & MESH_PATH_SN_VALID)) ||
603 SN_LT(mpath->sn, target_sn)) {
604 mpath->sn = target_sn;
605 mpath->flags |= MESH_PATH_SN_VALID;
606 } else if ((!(target_flags & IEEE80211_PREQ_TO_FLAG)) &&
607 (mpath->flags & MESH_PATH_ACTIVE)) {
609 target_metric = mpath->metric;
610 target_sn = mpath->sn;
611 /* Case E2 of sec 13.10.9.3 IEEE 802.11-2012*/
612 target_flags |= IEEE80211_PREQ_TO_FLAG;
619 lifetime = PREQ_IE_LIFETIME(preq_elem);
620 ttl = ifmsh->mshcfg.element_ttl;
622 mhwmp_dbg(sdata, "replying to the PREQ\n");
623 mesh_path_sel_frame_tx(MPATH_PREP, 0, orig_addr,
624 orig_sn, 0, target_addr,
625 target_sn, mgmt->sa, 0, ttl,
626 lifetime, target_metric, 0,
629 ifmsh->mshstats.dropped_frames_ttl++;
633 if (forward && ifmsh->mshcfg.dot11MeshForwarding) {
637 ttl = PREQ_IE_TTL(preq_elem);
638 lifetime = PREQ_IE_LIFETIME(preq_elem);
640 ifmsh->mshstats.dropped_frames_ttl++;
643 mhwmp_dbg(sdata, "forwarding the PREQ from %pM\n", orig_addr);
645 preq_id = PREQ_IE_PREQ_ID(preq_elem);
646 hopcount = PREQ_IE_HOPCOUNT(preq_elem) + 1;
647 da = (mpath && mpath->is_root) ?
648 mpath->rann_snd_addr : broadcast_addr;
650 if (flags & IEEE80211_PREQ_PROACTIVE_PREP_FLAG) {
651 target_addr = PREQ_IE_TARGET_ADDR(preq_elem);
652 target_sn = PREQ_IE_TARGET_SN(preq_elem);
655 mesh_path_sel_frame_tx(MPATH_PREQ, flags, orig_addr,
656 orig_sn, target_flags, target_addr,
657 target_sn, da, hopcount, ttl, lifetime,
658 orig_metric, preq_id, sdata);
659 if (!is_multicast_ether_addr(da))
660 ifmsh->mshstats.fwded_unicast++;
662 ifmsh->mshstats.fwded_mcast++;
663 ifmsh->mshstats.fwded_frames++;
668 static inline struct sta_info *
669 next_hop_deref_protected(struct mesh_path *mpath)
671 return rcu_dereference_protected(mpath->next_hop,
672 lockdep_is_held(&mpath->state_lock));
676 static void hwmp_prep_frame_process(struct ieee80211_sub_if_data *sdata,
677 struct ieee80211_mgmt *mgmt,
678 const u8 *prep_elem, u32 metric)
680 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
681 struct mesh_path *mpath;
682 const u8 *target_addr, *orig_addr;
683 u8 ttl, hopcount, flags;
684 u8 next_hop[ETH_ALEN];
685 u32 target_sn, orig_sn, lifetime;
687 mhwmp_dbg(sdata, "received PREP from %pM\n",
688 PREP_IE_TARGET_ADDR(prep_elem));
690 orig_addr = PREP_IE_ORIG_ADDR(prep_elem);
691 if (ether_addr_equal(orig_addr, sdata->vif.addr))
692 /* destination, no forwarding required */
695 if (!ifmsh->mshcfg.dot11MeshForwarding)
698 ttl = PREP_IE_TTL(prep_elem);
700 sdata->u.mesh.mshstats.dropped_frames_ttl++;
705 mpath = mesh_path_lookup(sdata, orig_addr);
707 spin_lock_bh(&mpath->state_lock);
710 if (!(mpath->flags & MESH_PATH_ACTIVE)) {
711 spin_unlock_bh(&mpath->state_lock);
714 memcpy(next_hop, next_hop_deref_protected(mpath)->sta.addr, ETH_ALEN);
715 spin_unlock_bh(&mpath->state_lock);
717 flags = PREP_IE_FLAGS(prep_elem);
718 lifetime = PREP_IE_LIFETIME(prep_elem);
719 hopcount = PREP_IE_HOPCOUNT(prep_elem) + 1;
720 target_addr = PREP_IE_TARGET_ADDR(prep_elem);
721 target_sn = PREP_IE_TARGET_SN(prep_elem);
722 orig_sn = PREP_IE_ORIG_SN(prep_elem);
724 mesh_path_sel_frame_tx(MPATH_PREP, flags, orig_addr, orig_sn, 0,
725 target_addr, target_sn, next_hop, hopcount,
726 ttl, lifetime, metric, 0, sdata);
729 sdata->u.mesh.mshstats.fwded_unicast++;
730 sdata->u.mesh.mshstats.fwded_frames++;
735 sdata->u.mesh.mshstats.dropped_frames_no_route++;
738 static void hwmp_perr_frame_process(struct ieee80211_sub_if_data *sdata,
739 struct ieee80211_mgmt *mgmt,
742 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
743 struct mesh_path *mpath;
745 const u8 *ta, *target_addr;
750 ttl = PERR_IE_TTL(perr_elem);
752 ifmsh->mshstats.dropped_frames_ttl++;
756 target_addr = PERR_IE_TARGET_ADDR(perr_elem);
757 target_sn = PERR_IE_TARGET_SN(perr_elem);
758 target_rcode = PERR_IE_TARGET_RCODE(perr_elem);
761 mpath = mesh_path_lookup(sdata, target_addr);
763 struct sta_info *sta;
765 spin_lock_bh(&mpath->state_lock);
766 sta = next_hop_deref_protected(mpath);
767 if (mpath->flags & MESH_PATH_ACTIVE &&
768 ether_addr_equal(ta, sta->sta.addr) &&
769 !(mpath->flags & MESH_PATH_FIXED) &&
770 (!(mpath->flags & MESH_PATH_SN_VALID) ||
771 SN_GT(target_sn, mpath->sn) || target_sn == 0)) {
772 mpath->flags &= ~MESH_PATH_ACTIVE;
774 mpath->sn = target_sn;
777 spin_unlock_bh(&mpath->state_lock);
778 if (!ifmsh->mshcfg.dot11MeshForwarding)
780 mesh_path_error_tx(sdata, ttl, target_addr,
781 target_sn, target_rcode,
784 spin_unlock_bh(&mpath->state_lock);
790 static void hwmp_rann_frame_process(struct ieee80211_sub_if_data *sdata,
791 struct ieee80211_mgmt *mgmt,
792 const struct ieee80211_rann_ie *rann)
794 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
795 struct ieee80211_local *local = sdata->local;
796 struct sta_info *sta;
797 struct mesh_path *mpath;
798 u8 ttl, flags, hopcount;
800 u32 orig_sn, metric, metric_txsta, interval;
803 ttl = rann->rann_ttl;
804 flags = rann->rann_flags;
805 root_is_gate = !!(flags & RANN_FLAG_IS_GATE);
806 orig_addr = rann->rann_addr;
807 orig_sn = le32_to_cpu(rann->rann_seq);
808 interval = le32_to_cpu(rann->rann_interval);
809 hopcount = rann->rann_hopcount;
811 metric = le32_to_cpu(rann->rann_metric);
813 /* Ignore our own RANNs */
814 if (ether_addr_equal(orig_addr, sdata->vif.addr))
818 "received RANN from %pM via neighbour %pM (is_gate=%d)\n",
819 orig_addr, mgmt->sa, root_is_gate);
822 sta = sta_info_get(sdata, mgmt->sa);
828 metric_txsta = airtime_link_metric_get(local, sta);
830 mpath = mesh_path_lookup(sdata, orig_addr);
832 mpath = mesh_path_add(sdata, orig_addr);
835 sdata->u.mesh.mshstats.dropped_frames_no_route++;
840 if (!(SN_LT(mpath->sn, orig_sn)) &&
841 !(mpath->sn == orig_sn && metric < mpath->rann_metric)) {
846 if ((!(mpath->flags & (MESH_PATH_ACTIVE | MESH_PATH_RESOLVING)) ||
847 (time_after(jiffies, mpath->last_preq_to_root +
848 root_path_confirmation_jiffies(sdata)) ||
849 time_before(jiffies, mpath->last_preq_to_root))) &&
850 !(mpath->flags & MESH_PATH_FIXED) && (ttl != 0)) {
852 "time to refresh root mpath %pM\n",
854 mesh_queue_preq(mpath, PREQ_Q_F_START | PREQ_Q_F_REFRESH);
855 mpath->last_preq_to_root = jiffies;
859 mpath->rann_metric = metric + metric_txsta;
860 mpath->is_root = true;
861 /* Recording RANNs sender address to send individually
862 * addressed PREQs destined for root mesh STA */
863 memcpy(mpath->rann_snd_addr, mgmt->sa, ETH_ALEN);
866 mesh_path_add_gate(mpath);
869 ifmsh->mshstats.dropped_frames_ttl++;
875 if (ifmsh->mshcfg.dot11MeshForwarding) {
876 mesh_path_sel_frame_tx(MPATH_RANN, flags, orig_addr,
877 orig_sn, 0, NULL, 0, broadcast_addr,
878 hopcount, ttl, interval,
879 metric + metric_txsta, 0, sdata);
886 void mesh_rx_path_sel_frame(struct ieee80211_sub_if_data *sdata,
887 struct ieee80211_mgmt *mgmt, size_t len)
889 struct ieee802_11_elems elems;
892 struct sta_info *sta;
894 /* need action_code */
895 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
899 sta = sta_info_get(sdata, mgmt->sa);
900 if (!sta || sta->mesh->plink_state != NL80211_PLINK_ESTAB) {
906 baselen = (u8 *) mgmt->u.action.u.mesh_action.variable - (u8 *) mgmt;
907 ieee802_11_parse_elems(mgmt->u.action.u.mesh_action.variable,
908 len - baselen, false, &elems);
911 if (elems.preq_len != 37)
912 /* Right now we support just 1 destination and no AE */
914 path_metric = hwmp_route_info_get(sdata, mgmt, elems.preq,
917 hwmp_preq_frame_process(sdata, mgmt, elems.preq,
921 if (elems.prep_len != 31)
922 /* Right now we support no AE */
924 path_metric = hwmp_route_info_get(sdata, mgmt, elems.prep,
927 hwmp_prep_frame_process(sdata, mgmt, elems.prep,
931 if (elems.perr_len != 15)
932 /* Right now we support only one destination per PERR */
934 hwmp_perr_frame_process(sdata, mgmt, elems.perr);
937 hwmp_rann_frame_process(sdata, mgmt, elems.rann);
941 * mesh_queue_preq - queue a PREQ to a given destination
943 * @mpath: mesh path to discover
944 * @flags: special attributes of the PREQ to be sent
946 * Locking: the function must be called from within a rcu read lock block.
949 static void mesh_queue_preq(struct mesh_path *mpath, u8 flags)
951 struct ieee80211_sub_if_data *sdata = mpath->sdata;
952 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
953 struct mesh_preq_queue *preq_node;
955 preq_node = kmalloc(sizeof(struct mesh_preq_queue), GFP_ATOMIC);
957 mhwmp_dbg(sdata, "could not allocate PREQ node\n");
961 spin_lock_bh(&ifmsh->mesh_preq_queue_lock);
962 if (ifmsh->preq_queue_len == MAX_PREQ_QUEUE_LEN) {
963 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
965 if (printk_ratelimit())
966 mhwmp_dbg(sdata, "PREQ node queue full\n");
970 spin_lock(&mpath->state_lock);
971 if (mpath->flags & MESH_PATH_REQ_QUEUED) {
972 spin_unlock(&mpath->state_lock);
973 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
978 memcpy(preq_node->dst, mpath->dst, ETH_ALEN);
979 preq_node->flags = flags;
981 mpath->flags |= MESH_PATH_REQ_QUEUED;
982 spin_unlock(&mpath->state_lock);
984 list_add_tail(&preq_node->list, &ifmsh->preq_queue.list);
985 ++ifmsh->preq_queue_len;
986 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
988 if (time_after(jiffies, ifmsh->last_preq + min_preq_int_jiff(sdata)))
989 ieee80211_queue_work(&sdata->local->hw, &sdata->work);
991 else if (time_before(jiffies, ifmsh->last_preq)) {
992 /* avoid long wait if did not send preqs for a long time
993 * and jiffies wrapped around
995 ifmsh->last_preq = jiffies - min_preq_int_jiff(sdata) - 1;
996 ieee80211_queue_work(&sdata->local->hw, &sdata->work);
998 mod_timer(&ifmsh->mesh_path_timer, ifmsh->last_preq +
999 min_preq_int_jiff(sdata));
1003 * mesh_path_start_discovery - launch a path discovery from the PREQ queue
1005 * @sdata: local mesh subif
1007 void mesh_path_start_discovery(struct ieee80211_sub_if_data *sdata)
1009 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1010 struct mesh_preq_queue *preq_node;
1011 struct mesh_path *mpath;
1012 u8 ttl, target_flags = 0;
1016 spin_lock_bh(&ifmsh->mesh_preq_queue_lock);
1017 if (!ifmsh->preq_queue_len ||
1018 time_before(jiffies, ifmsh->last_preq +
1019 min_preq_int_jiff(sdata))) {
1020 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
1024 preq_node = list_first_entry(&ifmsh->preq_queue.list,
1025 struct mesh_preq_queue, list);
1026 list_del(&preq_node->list);
1027 --ifmsh->preq_queue_len;
1028 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
1031 mpath = mesh_path_lookup(sdata, preq_node->dst);
1035 spin_lock_bh(&mpath->state_lock);
1036 if (mpath->flags & (MESH_PATH_DELETED | MESH_PATH_FIXED)) {
1037 spin_unlock_bh(&mpath->state_lock);
1040 mpath->flags &= ~MESH_PATH_REQ_QUEUED;
1041 if (preq_node->flags & PREQ_Q_F_START) {
1042 if (mpath->flags & MESH_PATH_RESOLVING) {
1043 spin_unlock_bh(&mpath->state_lock);
1046 mpath->flags &= ~MESH_PATH_RESOLVED;
1047 mpath->flags |= MESH_PATH_RESOLVING;
1048 mpath->discovery_retries = 0;
1049 mpath->discovery_timeout = disc_timeout_jiff(sdata);
1051 } else if (!(mpath->flags & MESH_PATH_RESOLVING) ||
1052 mpath->flags & MESH_PATH_RESOLVED) {
1053 mpath->flags &= ~MESH_PATH_RESOLVING;
1054 spin_unlock_bh(&mpath->state_lock);
1058 ifmsh->last_preq = jiffies;
1060 if (time_after(jiffies, ifmsh->last_sn_update +
1061 net_traversal_jiffies(sdata)) ||
1062 time_before(jiffies, ifmsh->last_sn_update)) {
1064 sdata->u.mesh.last_sn_update = jiffies;
1066 lifetime = default_lifetime(sdata);
1067 ttl = sdata->u.mesh.mshcfg.element_ttl;
1069 sdata->u.mesh.mshstats.dropped_frames_ttl++;
1070 spin_unlock_bh(&mpath->state_lock);
1074 if (preq_node->flags & PREQ_Q_F_REFRESH)
1075 target_flags |= IEEE80211_PREQ_TO_FLAG;
1077 target_flags &= ~IEEE80211_PREQ_TO_FLAG;
1079 spin_unlock_bh(&mpath->state_lock);
1080 da = (mpath->is_root) ? mpath->rann_snd_addr : broadcast_addr;
1081 mesh_path_sel_frame_tx(MPATH_PREQ, 0, sdata->vif.addr, ifmsh->sn,
1082 target_flags, mpath->dst, mpath->sn, da, 0,
1083 ttl, lifetime, 0, ifmsh->preq_id++, sdata);
1084 mod_timer(&mpath->timer, jiffies + mpath->discovery_timeout);
1092 * mesh_nexthop_resolve - lookup next hop; conditionally start path discovery
1094 * @skb: 802.11 frame to be sent
1095 * @sdata: network subif the frame will be sent through
1097 * Lookup next hop for given skb and start path discovery if no
1098 * forwarding information is found.
1100 * Returns: 0 if the next hop was found and -ENOENT if the frame was queued.
1101 * skb is freeed here if no mpath could be allocated.
1103 int mesh_nexthop_resolve(struct ieee80211_sub_if_data *sdata,
1104 struct sk_buff *skb)
1106 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1107 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1108 struct mesh_path *mpath;
1109 struct sk_buff *skb_to_free = NULL;
1110 u8 *target_addr = hdr->addr3;
1113 /* Nulls are only sent to peers for PS and should be pre-addressed */
1114 if (ieee80211_is_qos_nullfunc(hdr->frame_control))
1118 err = mesh_nexthop_lookup(sdata, skb);
1122 /* no nexthop found, start resolving */
1123 mpath = mesh_path_lookup(sdata, target_addr);
1125 mpath = mesh_path_add(sdata, target_addr);
1126 if (IS_ERR(mpath)) {
1127 mesh_path_discard_frame(sdata, skb);
1128 err = PTR_ERR(mpath);
1133 if (!(mpath->flags & MESH_PATH_RESOLVING))
1134 mesh_queue_preq(mpath, PREQ_Q_F_START);
1136 if (skb_queue_len(&mpath->frame_queue) >= MESH_FRAME_QUEUE_LEN)
1137 skb_to_free = skb_dequeue(&mpath->frame_queue);
1139 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1140 ieee80211_set_qos_hdr(sdata, skb);
1141 skb_queue_tail(&mpath->frame_queue, skb);
1144 mesh_path_discard_frame(sdata, skb_to_free);
1152 * mesh_nexthop_lookup - put the appropriate next hop on a mesh frame. Calling
1153 * this function is considered "using" the associated mpath, so preempt a path
1154 * refresh if this mpath expires soon.
1156 * @skb: 802.11 frame to be sent
1157 * @sdata: network subif the frame will be sent through
1159 * Returns: 0 if the next hop was found. Nonzero otherwise.
1161 int mesh_nexthop_lookup(struct ieee80211_sub_if_data *sdata,
1162 struct sk_buff *skb)
1164 struct mesh_path *mpath;
1165 struct sta_info *next_hop;
1166 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1167 u8 *target_addr = hdr->addr3;
1171 mpath = mesh_path_lookup(sdata, target_addr);
1173 if (!mpath || !(mpath->flags & MESH_PATH_ACTIVE))
1176 if (time_after(jiffies,
1178 msecs_to_jiffies(sdata->u.mesh.mshcfg.path_refresh_time)) &&
1179 ether_addr_equal(sdata->vif.addr, hdr->addr4) &&
1180 !(mpath->flags & MESH_PATH_RESOLVING) &&
1181 !(mpath->flags & MESH_PATH_FIXED))
1182 mesh_queue_preq(mpath, PREQ_Q_F_START | PREQ_Q_F_REFRESH);
1184 next_hop = rcu_dereference(mpath->next_hop);
1186 memcpy(hdr->addr1, next_hop->sta.addr, ETH_ALEN);
1187 memcpy(hdr->addr2, sdata->vif.addr, ETH_ALEN);
1188 ieee80211_mps_set_frame_flags(sdata, next_hop, hdr);
1197 void mesh_path_timer(unsigned long data)
1199 struct mesh_path *mpath = (void *) data;
1200 struct ieee80211_sub_if_data *sdata = mpath->sdata;
1203 if (sdata->local->quiescing)
1206 spin_lock_bh(&mpath->state_lock);
1207 if (mpath->flags & MESH_PATH_RESOLVED ||
1208 (!(mpath->flags & MESH_PATH_RESOLVING))) {
1209 mpath->flags &= ~(MESH_PATH_RESOLVING | MESH_PATH_RESOLVED);
1210 spin_unlock_bh(&mpath->state_lock);
1211 } else if (mpath->discovery_retries < max_preq_retries(sdata)) {
1212 ++mpath->discovery_retries;
1213 mpath->discovery_timeout *= 2;
1214 mpath->flags &= ~MESH_PATH_REQ_QUEUED;
1215 spin_unlock_bh(&mpath->state_lock);
1216 mesh_queue_preq(mpath, 0);
1218 mpath->flags &= ~(MESH_PATH_RESOLVING |
1219 MESH_PATH_RESOLVED |
1220 MESH_PATH_REQ_QUEUED);
1221 mpath->exp_time = jiffies;
1222 spin_unlock_bh(&mpath->state_lock);
1223 if (!mpath->is_gate && mesh_gate_num(sdata) > 0) {
1224 ret = mesh_path_send_to_gates(mpath);
1226 mhwmp_dbg(sdata, "no gate was reachable\n");
1228 mesh_path_flush_pending(mpath);
1232 void mesh_path_tx_root_frame(struct ieee80211_sub_if_data *sdata)
1234 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1235 u32 interval = ifmsh->mshcfg.dot11MeshHWMPRannInterval;
1236 u8 flags, target_flags = 0;
1238 flags = (ifmsh->mshcfg.dot11MeshGateAnnouncementProtocol)
1239 ? RANN_FLAG_IS_GATE : 0;
1241 switch (ifmsh->mshcfg.dot11MeshHWMPRootMode) {
1242 case IEEE80211_PROACTIVE_RANN:
1243 mesh_path_sel_frame_tx(MPATH_RANN, flags, sdata->vif.addr,
1244 ++ifmsh->sn, 0, NULL, 0, broadcast_addr,
1245 0, ifmsh->mshcfg.element_ttl,
1246 interval, 0, 0, sdata);
1248 case IEEE80211_PROACTIVE_PREQ_WITH_PREP:
1249 flags |= IEEE80211_PREQ_PROACTIVE_PREP_FLAG;
1250 case IEEE80211_PROACTIVE_PREQ_NO_PREP:
1251 interval = ifmsh->mshcfg.dot11MeshHWMPactivePathToRootTimeout;
1252 target_flags |= IEEE80211_PREQ_TO_FLAG |
1253 IEEE80211_PREQ_USN_FLAG;
1254 mesh_path_sel_frame_tx(MPATH_PREQ, flags, sdata->vif.addr,
1255 ++ifmsh->sn, target_flags,
1256 (u8 *) broadcast_addr, 0, broadcast_addr,
1257 0, ifmsh->mshcfg.element_ttl, interval,
1258 0, ifmsh->preq_id++, sdata);
1261 mhwmp_dbg(sdata, "Proactive mechanism not supported\n");