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
19 #define LINK_FAIL_THRESH 95
21 #define MAX_PREQ_QUEUE_LEN 64
23 static void mesh_queue_preq(struct mesh_path *, u8);
25 static inline u32 u32_field_get(const u8 *preq_elem, int offset, bool ae)
29 return get_unaligned_le32(preq_elem + offset);
32 static inline u16 u16_field_get(const u8 *preq_elem, int offset, bool ae)
36 return get_unaligned_le16(preq_elem + offset);
39 /* HWMP IE processing macros */
41 #define AE_F_SET(x) (*x & AE_F)
42 #define PREQ_IE_FLAGS(x) (*(x))
43 #define PREQ_IE_HOPCOUNT(x) (*(x + 1))
44 #define PREQ_IE_TTL(x) (*(x + 2))
45 #define PREQ_IE_PREQ_ID(x) u32_field_get(x, 3, 0)
46 #define PREQ_IE_ORIG_ADDR(x) (x + 7)
47 #define PREQ_IE_ORIG_SN(x) u32_field_get(x, 13, 0)
48 #define PREQ_IE_LIFETIME(x) u32_field_get(x, 17, AE_F_SET(x))
49 #define PREQ_IE_METRIC(x) u32_field_get(x, 21, AE_F_SET(x))
50 #define PREQ_IE_TARGET_F(x) (*(AE_F_SET(x) ? x + 32 : x + 26))
51 #define PREQ_IE_TARGET_ADDR(x) (AE_F_SET(x) ? x + 33 : x + 27)
52 #define PREQ_IE_TARGET_SN(x) u32_field_get(x, 33, AE_F_SET(x))
55 #define PREP_IE_FLAGS(x) PREQ_IE_FLAGS(x)
56 #define PREP_IE_HOPCOUNT(x) PREQ_IE_HOPCOUNT(x)
57 #define PREP_IE_TTL(x) PREQ_IE_TTL(x)
58 #define PREP_IE_ORIG_ADDR(x) (AE_F_SET(x) ? x + 27 : x + 21)
59 #define PREP_IE_ORIG_SN(x) u32_field_get(x, 27, AE_F_SET(x))
60 #define PREP_IE_LIFETIME(x) u32_field_get(x, 13, AE_F_SET(x))
61 #define PREP_IE_METRIC(x) u32_field_get(x, 17, AE_F_SET(x))
62 #define PREP_IE_TARGET_ADDR(x) (x + 3)
63 #define PREP_IE_TARGET_SN(x) u32_field_get(x, 9, 0)
65 #define PERR_IE_TTL(x) (*(x))
66 #define PERR_IE_TARGET_FLAGS(x) (*(x + 2))
67 #define PERR_IE_TARGET_ADDR(x) (x + 3)
68 #define PERR_IE_TARGET_SN(x) u32_field_get(x, 9, 0)
69 #define PERR_IE_TARGET_RCODE(x) u16_field_get(x, 13, 0)
71 #define MSEC_TO_TU(x) (x*1000/1024)
72 #define SN_GT(x, y) ((s32)(y - x) < 0)
73 #define SN_LT(x, y) ((s32)(x - y) < 0)
74 #define MAX_SANE_SN_DELTA 32
76 static inline u32 SN_DELTA(u32 x, u32 y)
78 return x >= y ? x - y : y - x;
81 #define net_traversal_jiffies(s) \
82 msecs_to_jiffies(s->u.mesh.mshcfg.dot11MeshHWMPnetDiameterTraversalTime)
83 #define default_lifetime(s) \
84 MSEC_TO_TU(s->u.mesh.mshcfg.dot11MeshHWMPactivePathTimeout)
85 #define min_preq_int_jiff(s) \
86 (msecs_to_jiffies(s->u.mesh.mshcfg.dot11MeshHWMPpreqMinInterval))
87 #define max_preq_retries(s) (s->u.mesh.mshcfg.dot11MeshHWMPmaxPREQretries)
88 #define disc_timeout_jiff(s) \
89 msecs_to_jiffies(sdata->u.mesh.mshcfg.min_discovery_timeout)
90 #define root_path_confirmation_jiffies(s) \
91 msecs_to_jiffies(sdata->u.mesh.mshcfg.dot11MeshHWMPconfirmationInterval)
93 enum mpath_frame_type {
100 static const u8 broadcast_addr[ETH_ALEN] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
102 static int mesh_path_sel_frame_tx(enum mpath_frame_type action, u8 flags,
103 const u8 *orig_addr, u32 orig_sn,
104 u8 target_flags, const u8 *target,
105 u32 target_sn, const u8 *da,
106 u8 hop_count, u8 ttl,
107 u32 lifetime, u32 metric, u32 preq_id,
108 struct ieee80211_sub_if_data *sdata)
110 struct ieee80211_local *local = sdata->local;
112 struct ieee80211_mgmt *mgmt;
114 int hdr_len = offsetof(struct ieee80211_mgmt, u.action.u.mesh_action) +
115 sizeof(mgmt->u.action.u.mesh_action);
117 skb = dev_alloc_skb(local->tx_headroom +
119 2 + 37); /* max HWMP IE */
122 skb_reserve(skb, local->tx_headroom);
123 mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len);
124 memset(mgmt, 0, hdr_len);
125 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
126 IEEE80211_STYPE_ACTION);
128 memcpy(mgmt->da, da, ETH_ALEN);
129 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
131 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
132 mgmt->u.action.category = WLAN_CATEGORY_MESH_ACTION;
133 mgmt->u.action.u.mesh_action.action_code =
134 WLAN_MESH_ACTION_HWMP_PATH_SELECTION;
138 mhwmp_dbg(sdata, "sending PREQ to %pM\n", target);
140 pos = skb_put(skb, 2 + ie_len);
141 *pos++ = WLAN_EID_PREQ;
144 mhwmp_dbg(sdata, "sending PREP to %pM\n", orig_addr);
146 pos = skb_put(skb, 2 + ie_len);
147 *pos++ = WLAN_EID_PREP;
150 mhwmp_dbg(sdata, "sending RANN from %pM\n", orig_addr);
151 ie_len = sizeof(struct ieee80211_rann_ie);
152 pos = skb_put(skb, 2 + ie_len);
153 *pos++ = WLAN_EID_RANN;
163 if (action == MPATH_PREP) {
164 memcpy(pos, target, ETH_ALEN);
166 put_unaligned_le32(target_sn, pos);
169 if (action == MPATH_PREQ) {
170 put_unaligned_le32(preq_id, pos);
173 memcpy(pos, orig_addr, ETH_ALEN);
175 put_unaligned_le32(orig_sn, pos);
178 put_unaligned_le32(lifetime, pos); /* interval for RANN */
180 put_unaligned_le32(metric, pos);
182 if (action == MPATH_PREQ) {
183 *pos++ = 1; /* destination count */
184 *pos++ = target_flags;
185 memcpy(pos, target, ETH_ALEN);
187 put_unaligned_le32(target_sn, pos);
189 } else if (action == MPATH_PREP) {
190 memcpy(pos, orig_addr, ETH_ALEN);
192 put_unaligned_le32(orig_sn, pos);
196 ieee80211_tx_skb(sdata, skb);
201 /* Headroom is not adjusted. Caller should ensure that skb has sufficient
202 * headroom in case the frame is encrypted. */
203 static void prepare_frame_for_deferred_tx(struct ieee80211_sub_if_data *sdata,
206 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
207 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
209 skb_reset_mac_header(skb);
210 skb_reset_network_header(skb);
211 skb_reset_transport_header(skb);
213 /* Send all internal mgmt frames on VO. Accordingly set TID to 7. */
214 skb_set_queue_mapping(skb, IEEE80211_AC_VO);
217 info->control.vif = &sdata->vif;
218 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
219 ieee80211_set_qos_hdr(sdata, skb);
220 ieee80211_mps_set_frame_flags(sdata, NULL, hdr);
224 * mesh_path_error_tx - Sends a PERR mesh management frame
226 * @ttl: allowed remaining hops
227 * @target: broken destination
228 * @target_sn: SN of the broken destination
229 * @target_rcode: reason code for this PERR
230 * @ra: node this frame is addressed to
231 * @sdata: local mesh subif
233 * Note: This function may be called with driver locks taken that the driver
234 * also acquires in the TX path. To avoid a deadlock we don't transmit the
235 * frame directly but add it to the pending queue instead.
237 int mesh_path_error_tx(struct ieee80211_sub_if_data *sdata,
238 u8 ttl, const u8 *target, u32 target_sn,
239 u16 target_rcode, const u8 *ra)
241 struct ieee80211_local *local = sdata->local;
243 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
244 struct ieee80211_mgmt *mgmt;
246 int hdr_len = offsetof(struct ieee80211_mgmt, u.action.u.mesh_action) +
247 sizeof(mgmt->u.action.u.mesh_action);
249 if (time_before(jiffies, ifmsh->next_perr))
252 skb = dev_alloc_skb(local->tx_headroom +
253 sdata->encrypt_headroom +
254 IEEE80211_ENCRYPT_TAILROOM +
256 2 + 15 /* PERR IE */);
259 skb_reserve(skb, local->tx_headroom + sdata->encrypt_headroom);
260 mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len);
261 memset(mgmt, 0, hdr_len);
262 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
263 IEEE80211_STYPE_ACTION);
265 memcpy(mgmt->da, ra, ETH_ALEN);
266 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
268 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
269 mgmt->u.action.category = WLAN_CATEGORY_MESH_ACTION;
270 mgmt->u.action.u.mesh_action.action_code =
271 WLAN_MESH_ACTION_HWMP_PATH_SELECTION;
273 pos = skb_put(skb, 2 + ie_len);
274 *pos++ = WLAN_EID_PERR;
278 /* number of destinations */
280 /* Flags field has AE bit only as defined in
281 * sec 8.4.2.117 IEEE802.11-2012
285 memcpy(pos, target, ETH_ALEN);
287 put_unaligned_le32(target_sn, pos);
289 put_unaligned_le16(target_rcode, pos);
291 /* see note in function header */
292 prepare_frame_for_deferred_tx(sdata, skb);
293 ifmsh->next_perr = TU_TO_EXP_TIME(
294 ifmsh->mshcfg.dot11MeshHWMPperrMinInterval);
295 ieee80211_add_pending_skb(local, skb);
299 void ieee80211s_update_metric(struct ieee80211_local *local,
300 struct sta_info *sta, struct sk_buff *skb)
302 struct ieee80211_tx_info *txinfo = IEEE80211_SKB_CB(skb);
303 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
306 if (!ieee80211_is_data(hdr->frame_control))
309 failed = !(txinfo->flags & IEEE80211_TX_STAT_ACK);
311 /* moving average, scaled to 100.
312 * feed failure as 100 and success as 0
314 ewma_mesh_fail_avg_add(&sta->mesh->fail_avg, failed * 100);
315 if (ewma_mesh_fail_avg_read(&sta->mesh->fail_avg) >
317 mesh_plink_broken(sta);
320 static u32 airtime_link_metric_get(struct ieee80211_local *local,
321 struct sta_info *sta)
323 struct rate_info rinfo;
324 /* This should be adjusted for each device */
325 int device_constant = 1 << ARITH_SHIFT;
326 int test_frame_len = TEST_FRAME_LEN << ARITH_SHIFT;
327 int s_unit = 1 << ARITH_SHIFT;
329 u32 tx_time, estimated_retx;
331 unsigned long fail_avg =
332 ewma_mesh_fail_avg_read(&sta->mesh->fail_avg);
334 /* Try to get rate based on HW/SW RC algorithm.
335 * Rate is returned in units of Kbps, correct this
336 * to comply with airtime calculation units
337 * Round up in case we get rate < 100Kbps
339 rate = DIV_ROUND_UP(sta_get_expected_throughput(sta), 100);
344 if (fail_avg > LINK_FAIL_THRESH)
347 sta_set_rate_info_tx(sta, &sta->tx_stats.last_rate, &rinfo);
348 rate = cfg80211_calculate_bitrate(&rinfo);
352 err = (fail_avg << ARITH_SHIFT) / 100;
355 /* bitrate is in units of 100 Kbps, while we need rate in units of
356 * 1Mbps. This will be corrected on tx_time computation.
358 tx_time = (device_constant + 10 * test_frame_len / rate);
359 estimated_retx = ((1 << (2 * ARITH_SHIFT)) / (s_unit - err));
360 result = (tx_time * estimated_retx) >> (2 * ARITH_SHIFT);
365 * hwmp_route_info_get - Update routing info to originator and transmitter
367 * @sdata: local mesh subif
368 * @mgmt: mesh management frame
369 * @hwmp_ie: hwmp information element (PREP or PREQ)
370 * @action: type of hwmp ie
372 * This function updates the path routing information to the originator and the
373 * transmitter of a HWMP PREQ or PREP frame.
375 * Returns: metric to frame originator or 0 if the frame should not be further
378 * Notes: this function is the only place (besides user-provided info) where
379 * path routing information is updated.
381 static u32 hwmp_route_info_get(struct ieee80211_sub_if_data *sdata,
382 struct ieee80211_mgmt *mgmt,
383 const u8 *hwmp_ie, enum mpath_frame_type action)
385 struct ieee80211_local *local = sdata->local;
386 struct mesh_path *mpath;
387 struct sta_info *sta;
389 const u8 *orig_addr, *ta;
390 u32 orig_sn, orig_metric;
391 unsigned long orig_lifetime, exp_time;
392 u32 last_hop_metric, new_metric;
396 sta = sta_info_get(sdata, mgmt->sa);
402 last_hop_metric = airtime_link_metric_get(local, sta);
403 /* Update and check originator routing info */
408 orig_addr = PREQ_IE_ORIG_ADDR(hwmp_ie);
409 orig_sn = PREQ_IE_ORIG_SN(hwmp_ie);
410 orig_lifetime = PREQ_IE_LIFETIME(hwmp_ie);
411 orig_metric = PREQ_IE_METRIC(hwmp_ie);
414 /* Originator here refers to the MP that was the target in the
415 * Path Request. We divert from the nomenclature in the draft
416 * so that we can easily use a single function to gather path
417 * information from both PREQ and PREP frames.
419 orig_addr = PREP_IE_TARGET_ADDR(hwmp_ie);
420 orig_sn = PREP_IE_TARGET_SN(hwmp_ie);
421 orig_lifetime = PREP_IE_LIFETIME(hwmp_ie);
422 orig_metric = PREP_IE_METRIC(hwmp_ie);
428 new_metric = orig_metric + last_hop_metric;
429 if (new_metric < orig_metric)
430 new_metric = MAX_METRIC;
431 exp_time = TU_TO_EXP_TIME(orig_lifetime);
433 if (ether_addr_equal(orig_addr, sdata->vif.addr)) {
434 /* This MP is the originator, we are not interested in this
435 * frame, except for updating transmitter's path info.
440 mpath = mesh_path_lookup(sdata, orig_addr);
442 spin_lock_bh(&mpath->state_lock);
443 if (mpath->flags & MESH_PATH_FIXED)
445 else if ((mpath->flags & MESH_PATH_ACTIVE) &&
446 (mpath->flags & MESH_PATH_SN_VALID)) {
447 if (SN_GT(mpath->sn, orig_sn) ||
448 (mpath->sn == orig_sn &&
449 new_metric >= mpath->metric)) {
453 } else if (!(mpath->flags & MESH_PATH_ACTIVE)) {
454 bool have_sn, newer_sn, bounced;
456 have_sn = mpath->flags & MESH_PATH_SN_VALID;
457 newer_sn = have_sn && SN_GT(orig_sn, mpath->sn);
459 (SN_DELTA(orig_sn, mpath->sn) >
462 if (!have_sn || newer_sn) {
463 /* if SN is newer than what we had
464 * then we can take it */;
465 } else if (bounced) {
466 /* if SN is way different than what
467 * we had then assume the other side
468 * rebooted or restarted */;
475 mpath = mesh_path_add(sdata, orig_addr);
480 spin_lock_bh(&mpath->state_lock);
484 mesh_path_assign_nexthop(mpath, sta);
485 mpath->flags |= MESH_PATH_SN_VALID;
486 mpath->metric = new_metric;
488 mpath->exp_time = time_after(mpath->exp_time, exp_time)
489 ? mpath->exp_time : exp_time;
490 mesh_path_activate(mpath);
491 spin_unlock_bh(&mpath->state_lock);
492 ewma_mesh_fail_avg_init(&sta->mesh->fail_avg);
493 /* init it at a low value - 0 start is tricky */
494 ewma_mesh_fail_avg_add(&sta->mesh->fail_avg, 1);
495 mesh_path_tx_pending(mpath);
496 /* draft says preq_id should be saved to, but there does
497 * not seem to be any use for it, skipping by now
500 spin_unlock_bh(&mpath->state_lock);
503 /* Update and check transmitter routing info */
505 if (ether_addr_equal(orig_addr, ta))
510 mpath = mesh_path_lookup(sdata, ta);
512 spin_lock_bh(&mpath->state_lock);
513 if ((mpath->flags & MESH_PATH_FIXED) ||
514 ((mpath->flags & MESH_PATH_ACTIVE) &&
515 (last_hop_metric > mpath->metric)))
518 mpath = mesh_path_add(sdata, ta);
523 spin_lock_bh(&mpath->state_lock);
527 mesh_path_assign_nexthop(mpath, sta);
528 mpath->metric = last_hop_metric;
529 mpath->exp_time = time_after(mpath->exp_time, exp_time)
530 ? mpath->exp_time : exp_time;
531 mesh_path_activate(mpath);
532 spin_unlock_bh(&mpath->state_lock);
533 ewma_mesh_fail_avg_init(&sta->mesh->fail_avg);
534 /* init it at a low value - 0 start is tricky */
535 ewma_mesh_fail_avg_add(&sta->mesh->fail_avg, 1);
536 mesh_path_tx_pending(mpath);
538 spin_unlock_bh(&mpath->state_lock);
543 return process ? new_metric : 0;
546 static void hwmp_preq_frame_process(struct ieee80211_sub_if_data *sdata,
547 struct ieee80211_mgmt *mgmt,
548 const u8 *preq_elem, u32 orig_metric)
550 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
551 struct mesh_path *mpath = NULL;
552 const u8 *target_addr, *orig_addr;
554 u8 target_flags, ttl, flags;
555 u32 orig_sn, target_sn, lifetime, target_metric = 0;
560 /* Update target SN, if present */
561 target_addr = PREQ_IE_TARGET_ADDR(preq_elem);
562 orig_addr = PREQ_IE_ORIG_ADDR(preq_elem);
563 target_sn = PREQ_IE_TARGET_SN(preq_elem);
564 orig_sn = PREQ_IE_ORIG_SN(preq_elem);
565 target_flags = PREQ_IE_TARGET_F(preq_elem);
566 /* Proactive PREQ gate announcements */
567 flags = PREQ_IE_FLAGS(preq_elem);
568 root_is_gate = !!(flags & RANN_FLAG_IS_GATE);
570 mhwmp_dbg(sdata, "received PREQ from %pM\n", orig_addr);
572 if (ether_addr_equal(target_addr, sdata->vif.addr)) {
573 mhwmp_dbg(sdata, "PREQ is for us\n");
577 if (time_after(jiffies, ifmsh->last_sn_update +
578 net_traversal_jiffies(sdata)) ||
579 time_before(jiffies, ifmsh->last_sn_update)) {
581 ifmsh->last_sn_update = jiffies;
583 target_sn = ifmsh->sn;
584 } else if (is_broadcast_ether_addr(target_addr) &&
585 (target_flags & IEEE80211_PREQ_TO_FLAG)) {
587 mpath = mesh_path_lookup(sdata, orig_addr);
589 if (flags & IEEE80211_PREQ_PROACTIVE_PREP_FLAG) {
591 target_addr = sdata->vif.addr;
592 target_sn = ++ifmsh->sn;
594 ifmsh->last_sn_update = jiffies;
597 mesh_path_add_gate(mpath);
602 mpath = mesh_path_lookup(sdata, target_addr);
604 if ((!(mpath->flags & MESH_PATH_SN_VALID)) ||
605 SN_LT(mpath->sn, target_sn)) {
606 mpath->sn = target_sn;
607 mpath->flags |= MESH_PATH_SN_VALID;
608 } else if ((!(target_flags & IEEE80211_PREQ_TO_FLAG)) &&
609 (mpath->flags & MESH_PATH_ACTIVE)) {
611 target_metric = mpath->metric;
612 target_sn = mpath->sn;
613 /* Case E2 of sec 13.10.9.3 IEEE 802.11-2012*/
614 target_flags |= IEEE80211_PREQ_TO_FLAG;
621 lifetime = PREQ_IE_LIFETIME(preq_elem);
622 ttl = ifmsh->mshcfg.element_ttl;
624 mhwmp_dbg(sdata, "replying to the PREQ\n");
625 mesh_path_sel_frame_tx(MPATH_PREP, 0, orig_addr,
626 orig_sn, 0, target_addr,
627 target_sn, mgmt->sa, 0, ttl,
628 lifetime, target_metric, 0,
631 ifmsh->mshstats.dropped_frames_ttl++;
635 if (forward && ifmsh->mshcfg.dot11MeshForwarding) {
639 ttl = PREQ_IE_TTL(preq_elem);
640 lifetime = PREQ_IE_LIFETIME(preq_elem);
642 ifmsh->mshstats.dropped_frames_ttl++;
645 mhwmp_dbg(sdata, "forwarding the PREQ from %pM\n", orig_addr);
647 preq_id = PREQ_IE_PREQ_ID(preq_elem);
648 hopcount = PREQ_IE_HOPCOUNT(preq_elem) + 1;
649 da = (mpath && mpath->is_root) ?
650 mpath->rann_snd_addr : broadcast_addr;
652 if (flags & IEEE80211_PREQ_PROACTIVE_PREP_FLAG) {
653 target_addr = PREQ_IE_TARGET_ADDR(preq_elem);
654 target_sn = PREQ_IE_TARGET_SN(preq_elem);
657 mesh_path_sel_frame_tx(MPATH_PREQ, flags, orig_addr,
658 orig_sn, target_flags, target_addr,
659 target_sn, da, hopcount, ttl, lifetime,
660 orig_metric, preq_id, sdata);
661 if (!is_multicast_ether_addr(da))
662 ifmsh->mshstats.fwded_unicast++;
664 ifmsh->mshstats.fwded_mcast++;
665 ifmsh->mshstats.fwded_frames++;
670 static inline struct sta_info *
671 next_hop_deref_protected(struct mesh_path *mpath)
673 return rcu_dereference_protected(mpath->next_hop,
674 lockdep_is_held(&mpath->state_lock));
678 static void hwmp_prep_frame_process(struct ieee80211_sub_if_data *sdata,
679 struct ieee80211_mgmt *mgmt,
680 const u8 *prep_elem, u32 metric)
682 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
683 struct mesh_path *mpath;
684 const u8 *target_addr, *orig_addr;
685 u8 ttl, hopcount, flags;
686 u8 next_hop[ETH_ALEN];
687 u32 target_sn, orig_sn, lifetime;
689 mhwmp_dbg(sdata, "received PREP from %pM\n",
690 PREP_IE_TARGET_ADDR(prep_elem));
692 orig_addr = PREP_IE_ORIG_ADDR(prep_elem);
693 if (ether_addr_equal(orig_addr, sdata->vif.addr))
694 /* destination, no forwarding required */
697 if (!ifmsh->mshcfg.dot11MeshForwarding)
700 ttl = PREP_IE_TTL(prep_elem);
702 sdata->u.mesh.mshstats.dropped_frames_ttl++;
707 mpath = mesh_path_lookup(sdata, orig_addr);
709 spin_lock_bh(&mpath->state_lock);
712 if (!(mpath->flags & MESH_PATH_ACTIVE)) {
713 spin_unlock_bh(&mpath->state_lock);
716 memcpy(next_hop, next_hop_deref_protected(mpath)->sta.addr, ETH_ALEN);
717 spin_unlock_bh(&mpath->state_lock);
719 flags = PREP_IE_FLAGS(prep_elem);
720 lifetime = PREP_IE_LIFETIME(prep_elem);
721 hopcount = PREP_IE_HOPCOUNT(prep_elem) + 1;
722 target_addr = PREP_IE_TARGET_ADDR(prep_elem);
723 target_sn = PREP_IE_TARGET_SN(prep_elem);
724 orig_sn = PREP_IE_ORIG_SN(prep_elem);
726 mesh_path_sel_frame_tx(MPATH_PREP, flags, orig_addr, orig_sn, 0,
727 target_addr, target_sn, next_hop, hopcount,
728 ttl, lifetime, metric, 0, sdata);
731 sdata->u.mesh.mshstats.fwded_unicast++;
732 sdata->u.mesh.mshstats.fwded_frames++;
737 sdata->u.mesh.mshstats.dropped_frames_no_route++;
740 static void hwmp_perr_frame_process(struct ieee80211_sub_if_data *sdata,
741 struct ieee80211_mgmt *mgmt,
744 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
745 struct mesh_path *mpath;
747 const u8 *ta, *target_addr;
752 ttl = PERR_IE_TTL(perr_elem);
754 ifmsh->mshstats.dropped_frames_ttl++;
758 target_addr = PERR_IE_TARGET_ADDR(perr_elem);
759 target_sn = PERR_IE_TARGET_SN(perr_elem);
760 target_rcode = PERR_IE_TARGET_RCODE(perr_elem);
763 mpath = mesh_path_lookup(sdata, target_addr);
765 struct sta_info *sta;
767 spin_lock_bh(&mpath->state_lock);
768 sta = next_hop_deref_protected(mpath);
769 if (mpath->flags & MESH_PATH_ACTIVE &&
770 ether_addr_equal(ta, sta->sta.addr) &&
771 !(mpath->flags & MESH_PATH_FIXED) &&
772 (!(mpath->flags & MESH_PATH_SN_VALID) ||
773 SN_GT(target_sn, mpath->sn) || target_sn == 0)) {
774 mpath->flags &= ~MESH_PATH_ACTIVE;
776 mpath->sn = target_sn;
779 spin_unlock_bh(&mpath->state_lock);
780 if (!ifmsh->mshcfg.dot11MeshForwarding)
782 mesh_path_error_tx(sdata, ttl, target_addr,
783 target_sn, target_rcode,
786 spin_unlock_bh(&mpath->state_lock);
792 static void hwmp_rann_frame_process(struct ieee80211_sub_if_data *sdata,
793 struct ieee80211_mgmt *mgmt,
794 const struct ieee80211_rann_ie *rann)
796 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
797 struct ieee80211_local *local = sdata->local;
798 struct sta_info *sta;
799 struct mesh_path *mpath;
800 u8 ttl, flags, hopcount;
802 u32 orig_sn, metric, metric_txsta, interval;
805 ttl = rann->rann_ttl;
806 flags = rann->rann_flags;
807 root_is_gate = !!(flags & RANN_FLAG_IS_GATE);
808 orig_addr = rann->rann_addr;
809 orig_sn = le32_to_cpu(rann->rann_seq);
810 interval = le32_to_cpu(rann->rann_interval);
811 hopcount = rann->rann_hopcount;
813 metric = le32_to_cpu(rann->rann_metric);
815 /* Ignore our own RANNs */
816 if (ether_addr_equal(orig_addr, sdata->vif.addr))
820 "received RANN from %pM via neighbour %pM (is_gate=%d)\n",
821 orig_addr, mgmt->sa, root_is_gate);
824 sta = sta_info_get(sdata, mgmt->sa);
830 metric_txsta = airtime_link_metric_get(local, sta);
832 mpath = mesh_path_lookup(sdata, orig_addr);
834 mpath = mesh_path_add(sdata, orig_addr);
837 sdata->u.mesh.mshstats.dropped_frames_no_route++;
842 if (!(SN_LT(mpath->sn, orig_sn)) &&
843 !(mpath->sn == orig_sn && metric < mpath->rann_metric)) {
848 if ((!(mpath->flags & (MESH_PATH_ACTIVE | MESH_PATH_RESOLVING)) ||
849 (time_after(jiffies, mpath->last_preq_to_root +
850 root_path_confirmation_jiffies(sdata)) ||
851 time_before(jiffies, mpath->last_preq_to_root))) &&
852 !(mpath->flags & MESH_PATH_FIXED) && (ttl != 0)) {
854 "time to refresh root mpath %pM\n",
856 mesh_queue_preq(mpath, PREQ_Q_F_START | PREQ_Q_F_REFRESH);
857 mpath->last_preq_to_root = jiffies;
861 mpath->rann_metric = metric + metric_txsta;
862 mpath->is_root = true;
863 /* Recording RANNs sender address to send individually
864 * addressed PREQs destined for root mesh STA */
865 memcpy(mpath->rann_snd_addr, mgmt->sa, ETH_ALEN);
868 mesh_path_add_gate(mpath);
871 ifmsh->mshstats.dropped_frames_ttl++;
877 if (ifmsh->mshcfg.dot11MeshForwarding) {
878 mesh_path_sel_frame_tx(MPATH_RANN, flags, orig_addr,
879 orig_sn, 0, NULL, 0, broadcast_addr,
880 hopcount, ttl, interval,
881 metric + metric_txsta, 0, sdata);
888 void mesh_rx_path_sel_frame(struct ieee80211_sub_if_data *sdata,
889 struct ieee80211_mgmt *mgmt, size_t len)
891 struct ieee802_11_elems elems;
894 struct sta_info *sta;
896 /* need action_code */
897 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
901 sta = sta_info_get(sdata, mgmt->sa);
902 if (!sta || sta->mesh->plink_state != NL80211_PLINK_ESTAB) {
908 baselen = (u8 *) mgmt->u.action.u.mesh_action.variable - (u8 *) mgmt;
909 ieee802_11_parse_elems(mgmt->u.action.u.mesh_action.variable,
910 len - baselen, false, &elems);
913 if (elems.preq_len != 37)
914 /* Right now we support just 1 destination and no AE */
916 path_metric = hwmp_route_info_get(sdata, mgmt, elems.preq,
919 hwmp_preq_frame_process(sdata, mgmt, elems.preq,
923 if (elems.prep_len != 31)
924 /* Right now we support no AE */
926 path_metric = hwmp_route_info_get(sdata, mgmt, elems.prep,
929 hwmp_prep_frame_process(sdata, mgmt, elems.prep,
933 if (elems.perr_len != 15)
934 /* Right now we support only one destination per PERR */
936 hwmp_perr_frame_process(sdata, mgmt, elems.perr);
939 hwmp_rann_frame_process(sdata, mgmt, elems.rann);
943 * mesh_queue_preq - queue a PREQ to a given destination
945 * @mpath: mesh path to discover
946 * @flags: special attributes of the PREQ to be sent
948 * Locking: the function must be called from within a rcu read lock block.
951 static void mesh_queue_preq(struct mesh_path *mpath, u8 flags)
953 struct ieee80211_sub_if_data *sdata = mpath->sdata;
954 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
955 struct mesh_preq_queue *preq_node;
957 preq_node = kmalloc(sizeof(struct mesh_preq_queue), GFP_ATOMIC);
959 mhwmp_dbg(sdata, "could not allocate PREQ node\n");
963 spin_lock_bh(&ifmsh->mesh_preq_queue_lock);
964 if (ifmsh->preq_queue_len == MAX_PREQ_QUEUE_LEN) {
965 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
967 if (printk_ratelimit())
968 mhwmp_dbg(sdata, "PREQ node queue full\n");
972 spin_lock(&mpath->state_lock);
973 if (mpath->flags & MESH_PATH_REQ_QUEUED) {
974 spin_unlock(&mpath->state_lock);
975 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
980 memcpy(preq_node->dst, mpath->dst, ETH_ALEN);
981 preq_node->flags = flags;
983 mpath->flags |= MESH_PATH_REQ_QUEUED;
984 spin_unlock(&mpath->state_lock);
986 list_add_tail(&preq_node->list, &ifmsh->preq_queue.list);
987 ++ifmsh->preq_queue_len;
988 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
990 if (time_after(jiffies, ifmsh->last_preq + min_preq_int_jiff(sdata)))
991 ieee80211_queue_work(&sdata->local->hw, &sdata->work);
993 else if (time_before(jiffies, ifmsh->last_preq)) {
994 /* avoid long wait if did not send preqs for a long time
995 * and jiffies wrapped around
997 ifmsh->last_preq = jiffies - min_preq_int_jiff(sdata) - 1;
998 ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1000 mod_timer(&ifmsh->mesh_path_timer, ifmsh->last_preq +
1001 min_preq_int_jiff(sdata));
1005 * mesh_path_start_discovery - launch a path discovery from the PREQ queue
1007 * @sdata: local mesh subif
1009 void mesh_path_start_discovery(struct ieee80211_sub_if_data *sdata)
1011 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1012 struct mesh_preq_queue *preq_node;
1013 struct mesh_path *mpath;
1014 u8 ttl, target_flags = 0;
1018 spin_lock_bh(&ifmsh->mesh_preq_queue_lock);
1019 if (!ifmsh->preq_queue_len ||
1020 time_before(jiffies, ifmsh->last_preq +
1021 min_preq_int_jiff(sdata))) {
1022 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
1026 preq_node = list_first_entry(&ifmsh->preq_queue.list,
1027 struct mesh_preq_queue, list);
1028 list_del(&preq_node->list);
1029 --ifmsh->preq_queue_len;
1030 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
1033 mpath = mesh_path_lookup(sdata, preq_node->dst);
1037 spin_lock_bh(&mpath->state_lock);
1038 if (mpath->flags & (MESH_PATH_DELETED | MESH_PATH_FIXED)) {
1039 spin_unlock_bh(&mpath->state_lock);
1042 mpath->flags &= ~MESH_PATH_REQ_QUEUED;
1043 if (preq_node->flags & PREQ_Q_F_START) {
1044 if (mpath->flags & MESH_PATH_RESOLVING) {
1045 spin_unlock_bh(&mpath->state_lock);
1048 mpath->flags &= ~MESH_PATH_RESOLVED;
1049 mpath->flags |= MESH_PATH_RESOLVING;
1050 mpath->discovery_retries = 0;
1051 mpath->discovery_timeout = disc_timeout_jiff(sdata);
1053 } else if (!(mpath->flags & MESH_PATH_RESOLVING) ||
1054 mpath->flags & MESH_PATH_RESOLVED) {
1055 mpath->flags &= ~MESH_PATH_RESOLVING;
1056 spin_unlock_bh(&mpath->state_lock);
1060 ifmsh->last_preq = jiffies;
1062 if (time_after(jiffies, ifmsh->last_sn_update +
1063 net_traversal_jiffies(sdata)) ||
1064 time_before(jiffies, ifmsh->last_sn_update)) {
1066 sdata->u.mesh.last_sn_update = jiffies;
1068 lifetime = default_lifetime(sdata);
1069 ttl = sdata->u.mesh.mshcfg.element_ttl;
1071 sdata->u.mesh.mshstats.dropped_frames_ttl++;
1072 spin_unlock_bh(&mpath->state_lock);
1076 if (preq_node->flags & PREQ_Q_F_REFRESH)
1077 target_flags |= IEEE80211_PREQ_TO_FLAG;
1079 target_flags &= ~IEEE80211_PREQ_TO_FLAG;
1081 spin_unlock_bh(&mpath->state_lock);
1082 da = (mpath->is_root) ? mpath->rann_snd_addr : broadcast_addr;
1083 mesh_path_sel_frame_tx(MPATH_PREQ, 0, sdata->vif.addr, ifmsh->sn,
1084 target_flags, mpath->dst, mpath->sn, da, 0,
1085 ttl, lifetime, 0, ifmsh->preq_id++, sdata);
1086 mod_timer(&mpath->timer, jiffies + mpath->discovery_timeout);
1094 * mesh_nexthop_resolve - lookup next hop; conditionally start path discovery
1096 * @skb: 802.11 frame to be sent
1097 * @sdata: network subif the frame will be sent through
1099 * Lookup next hop for given skb and start path discovery if no
1100 * forwarding information is found.
1102 * Returns: 0 if the next hop was found and -ENOENT if the frame was queued.
1103 * skb is freeed here if no mpath could be allocated.
1105 int mesh_nexthop_resolve(struct ieee80211_sub_if_data *sdata,
1106 struct sk_buff *skb)
1108 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1109 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1110 struct mesh_path *mpath;
1111 struct sk_buff *skb_to_free = NULL;
1112 u8 *target_addr = hdr->addr3;
1115 /* Nulls are only sent to peers for PS and should be pre-addressed */
1116 if (ieee80211_is_qos_nullfunc(hdr->frame_control))
1120 err = mesh_nexthop_lookup(sdata, skb);
1124 /* no nexthop found, start resolving */
1125 mpath = mesh_path_lookup(sdata, target_addr);
1127 mpath = mesh_path_add(sdata, target_addr);
1128 if (IS_ERR(mpath)) {
1129 mesh_path_discard_frame(sdata, skb);
1130 err = PTR_ERR(mpath);
1135 if (!(mpath->flags & MESH_PATH_RESOLVING))
1136 mesh_queue_preq(mpath, PREQ_Q_F_START);
1138 if (skb_queue_len(&mpath->frame_queue) >= MESH_FRAME_QUEUE_LEN)
1139 skb_to_free = skb_dequeue(&mpath->frame_queue);
1141 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1142 ieee80211_set_qos_hdr(sdata, skb);
1143 skb_queue_tail(&mpath->frame_queue, skb);
1146 mesh_path_discard_frame(sdata, skb_to_free);
1154 * mesh_nexthop_lookup - put the appropriate next hop on a mesh frame. Calling
1155 * this function is considered "using" the associated mpath, so preempt a path
1156 * refresh if this mpath expires soon.
1158 * @skb: 802.11 frame to be sent
1159 * @sdata: network subif the frame will be sent through
1161 * Returns: 0 if the next hop was found. Nonzero otherwise.
1163 int mesh_nexthop_lookup(struct ieee80211_sub_if_data *sdata,
1164 struct sk_buff *skb)
1166 struct mesh_path *mpath;
1167 struct sta_info *next_hop;
1168 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1169 u8 *target_addr = hdr->addr3;
1173 mpath = mesh_path_lookup(sdata, target_addr);
1175 if (!mpath || !(mpath->flags & MESH_PATH_ACTIVE))
1178 if (time_after(jiffies,
1180 msecs_to_jiffies(sdata->u.mesh.mshcfg.path_refresh_time)) &&
1181 ether_addr_equal(sdata->vif.addr, hdr->addr4) &&
1182 !(mpath->flags & MESH_PATH_RESOLVING) &&
1183 !(mpath->flags & MESH_PATH_FIXED))
1184 mesh_queue_preq(mpath, PREQ_Q_F_START | PREQ_Q_F_REFRESH);
1186 next_hop = rcu_dereference(mpath->next_hop);
1188 memcpy(hdr->addr1, next_hop->sta.addr, ETH_ALEN);
1189 memcpy(hdr->addr2, sdata->vif.addr, ETH_ALEN);
1190 ieee80211_mps_set_frame_flags(sdata, next_hop, hdr);
1199 void mesh_path_timer(unsigned long data)
1201 struct mesh_path *mpath = (void *) data;
1202 struct ieee80211_sub_if_data *sdata = mpath->sdata;
1205 if (sdata->local->quiescing)
1208 spin_lock_bh(&mpath->state_lock);
1209 if (mpath->flags & MESH_PATH_RESOLVED ||
1210 (!(mpath->flags & MESH_PATH_RESOLVING))) {
1211 mpath->flags &= ~(MESH_PATH_RESOLVING | MESH_PATH_RESOLVED);
1212 spin_unlock_bh(&mpath->state_lock);
1213 } else if (mpath->discovery_retries < max_preq_retries(sdata)) {
1214 ++mpath->discovery_retries;
1215 mpath->discovery_timeout *= 2;
1216 mpath->flags &= ~MESH_PATH_REQ_QUEUED;
1217 spin_unlock_bh(&mpath->state_lock);
1218 mesh_queue_preq(mpath, 0);
1220 mpath->flags &= ~(MESH_PATH_RESOLVING |
1221 MESH_PATH_RESOLVED |
1222 MESH_PATH_REQ_QUEUED);
1223 mpath->exp_time = jiffies;
1224 spin_unlock_bh(&mpath->state_lock);
1225 if (!mpath->is_gate && mesh_gate_num(sdata) > 0) {
1226 ret = mesh_path_send_to_gates(mpath);
1228 mhwmp_dbg(sdata, "no gate was reachable\n");
1230 mesh_path_flush_pending(mpath);
1234 void mesh_path_tx_root_frame(struct ieee80211_sub_if_data *sdata)
1236 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1237 u32 interval = ifmsh->mshcfg.dot11MeshHWMPRannInterval;
1238 u8 flags, target_flags = 0;
1240 flags = (ifmsh->mshcfg.dot11MeshGateAnnouncementProtocol)
1241 ? RANN_FLAG_IS_GATE : 0;
1243 switch (ifmsh->mshcfg.dot11MeshHWMPRootMode) {
1244 case IEEE80211_PROACTIVE_RANN:
1245 mesh_path_sel_frame_tx(MPATH_RANN, flags, sdata->vif.addr,
1246 ++ifmsh->sn, 0, NULL, 0, broadcast_addr,
1247 0, ifmsh->mshcfg.element_ttl,
1248 interval, 0, 0, sdata);
1250 case IEEE80211_PROACTIVE_PREQ_WITH_PREP:
1251 flags |= IEEE80211_PREQ_PROACTIVE_PREP_FLAG;
1252 case IEEE80211_PROACTIVE_PREQ_NO_PREP:
1253 interval = ifmsh->mshcfg.dot11MeshHWMPactivePathToRootTimeout;
1254 target_flags |= IEEE80211_PREQ_TO_FLAG |
1255 IEEE80211_PREQ_USN_FLAG;
1256 mesh_path_sel_frame_tx(MPATH_PREQ, flags, sdata->vif.addr,
1257 ++ifmsh->sn, target_flags,
1258 (u8 *) broadcast_addr, 0, broadcast_addr,
1259 0, ifmsh->mshcfg.element_ttl, interval,
1260 0, ifmsh->preq_id++, sdata);
1263 mhwmp_dbg(sdata, "Proactive mechanism not supported\n");