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 sta->mesh->fail_avg =
312 ((80 * sta->mesh->fail_avg + 5) / 100 + 20 * failed);
313 if (sta->mesh->fail_avg > 95)
314 mesh_plink_broken(sta);
317 static u32 airtime_link_metric_get(struct ieee80211_local *local,
318 struct sta_info *sta)
320 struct rate_info rinfo;
321 /* This should be adjusted for each device */
322 int device_constant = 1 << ARITH_SHIFT;
323 int test_frame_len = TEST_FRAME_LEN << ARITH_SHIFT;
324 int s_unit = 1 << ARITH_SHIFT;
326 u32 tx_time, estimated_retx;
329 if (sta->mesh->plink_state != NL80211_PLINK_ESTAB)
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);
342 if (sta->mesh->fail_avg >= 100)
345 sta_set_rate_info_tx(sta, &sta->tx_stats.last_rate, &rinfo);
346 rate = cfg80211_calculate_bitrate(&rinfo);
350 err = (sta->mesh->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 = ((u64)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 mesh_path_tx_pending(mpath);
491 /* draft says preq_id should be saved to, but there does
492 * not seem to be any use for it, skipping by now
495 spin_unlock_bh(&mpath->state_lock);
498 /* Update and check transmitter routing info */
500 if (ether_addr_equal(orig_addr, ta))
505 mpath = mesh_path_lookup(sdata, ta);
507 spin_lock_bh(&mpath->state_lock);
508 if ((mpath->flags & MESH_PATH_FIXED) ||
509 ((mpath->flags & MESH_PATH_ACTIVE) &&
510 (last_hop_metric > mpath->metric)))
513 mpath = mesh_path_add(sdata, ta);
518 spin_lock_bh(&mpath->state_lock);
522 mesh_path_assign_nexthop(mpath, sta);
523 mpath->metric = last_hop_metric;
524 mpath->exp_time = time_after(mpath->exp_time, exp_time)
525 ? mpath->exp_time : exp_time;
526 mesh_path_activate(mpath);
527 spin_unlock_bh(&mpath->state_lock);
528 mesh_path_tx_pending(mpath);
530 spin_unlock_bh(&mpath->state_lock);
535 return process ? new_metric : 0;
538 static void hwmp_preq_frame_process(struct ieee80211_sub_if_data *sdata,
539 struct ieee80211_mgmt *mgmt,
540 const u8 *preq_elem, u32 orig_metric)
542 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
543 struct mesh_path *mpath = NULL;
544 const u8 *target_addr, *orig_addr;
546 u8 target_flags, ttl, flags;
547 u32 orig_sn, target_sn, lifetime, target_metric = 0;
552 /* Update target SN, if present */
553 target_addr = PREQ_IE_TARGET_ADDR(preq_elem);
554 orig_addr = PREQ_IE_ORIG_ADDR(preq_elem);
555 target_sn = PREQ_IE_TARGET_SN(preq_elem);
556 orig_sn = PREQ_IE_ORIG_SN(preq_elem);
557 target_flags = PREQ_IE_TARGET_F(preq_elem);
558 /* Proactive PREQ gate announcements */
559 flags = PREQ_IE_FLAGS(preq_elem);
560 root_is_gate = !!(flags & RANN_FLAG_IS_GATE);
562 mhwmp_dbg(sdata, "received PREQ from %pM\n", orig_addr);
564 if (ether_addr_equal(target_addr, sdata->vif.addr)) {
565 mhwmp_dbg(sdata, "PREQ is for us\n");
570 if (SN_GT(target_sn, ifmsh->sn))
571 ifmsh->sn = target_sn;
573 if (time_after(jiffies, ifmsh->last_sn_update +
574 net_traversal_jiffies(sdata)) ||
575 time_before(jiffies, ifmsh->last_sn_update)) {
577 ifmsh->last_sn_update = jiffies;
579 target_sn = ifmsh->sn;
580 } else if (is_broadcast_ether_addr(target_addr) &&
581 (target_flags & IEEE80211_PREQ_TO_FLAG)) {
583 mpath = mesh_path_lookup(sdata, orig_addr);
585 if (flags & IEEE80211_PREQ_PROACTIVE_PREP_FLAG) {
587 target_addr = sdata->vif.addr;
588 target_sn = ++ifmsh->sn;
590 ifmsh->last_sn_update = jiffies;
593 mesh_path_add_gate(mpath);
598 mpath = mesh_path_lookup(sdata, target_addr);
600 if ((!(mpath->flags & MESH_PATH_SN_VALID)) ||
601 SN_LT(mpath->sn, target_sn)) {
602 mpath->sn = target_sn;
603 mpath->flags |= MESH_PATH_SN_VALID;
604 } else if ((!(target_flags & IEEE80211_PREQ_TO_FLAG)) &&
605 (mpath->flags & MESH_PATH_ACTIVE)) {
607 target_metric = mpath->metric;
608 target_sn = mpath->sn;
609 /* Case E2 of sec 13.10.9.3 IEEE 802.11-2012*/
610 target_flags |= IEEE80211_PREQ_TO_FLAG;
617 lifetime = PREQ_IE_LIFETIME(preq_elem);
618 ttl = ifmsh->mshcfg.element_ttl;
620 mhwmp_dbg(sdata, "replying to the PREQ\n");
621 mesh_path_sel_frame_tx(MPATH_PREP, 0, orig_addr,
622 orig_sn, 0, target_addr,
623 target_sn, mgmt->sa, 0, ttl,
624 lifetime, target_metric, 0,
627 ifmsh->mshstats.dropped_frames_ttl++;
631 if (forward && ifmsh->mshcfg.dot11MeshForwarding) {
635 ttl = PREQ_IE_TTL(preq_elem);
636 lifetime = PREQ_IE_LIFETIME(preq_elem);
638 ifmsh->mshstats.dropped_frames_ttl++;
641 mhwmp_dbg(sdata, "forwarding the PREQ from %pM\n", orig_addr);
643 preq_id = PREQ_IE_PREQ_ID(preq_elem);
644 hopcount = PREQ_IE_HOPCOUNT(preq_elem) + 1;
645 da = (mpath && mpath->is_root) ?
646 mpath->rann_snd_addr : broadcast_addr;
648 if (flags & IEEE80211_PREQ_PROACTIVE_PREP_FLAG) {
649 target_addr = PREQ_IE_TARGET_ADDR(preq_elem);
650 target_sn = PREQ_IE_TARGET_SN(preq_elem);
653 mesh_path_sel_frame_tx(MPATH_PREQ, flags, orig_addr,
654 orig_sn, target_flags, target_addr,
655 target_sn, da, hopcount, ttl, lifetime,
656 orig_metric, preq_id, sdata);
657 if (!is_multicast_ether_addr(da))
658 ifmsh->mshstats.fwded_unicast++;
660 ifmsh->mshstats.fwded_mcast++;
661 ifmsh->mshstats.fwded_frames++;
666 static inline struct sta_info *
667 next_hop_deref_protected(struct mesh_path *mpath)
669 return rcu_dereference_protected(mpath->next_hop,
670 lockdep_is_held(&mpath->state_lock));
674 static void hwmp_prep_frame_process(struct ieee80211_sub_if_data *sdata,
675 struct ieee80211_mgmt *mgmt,
676 const u8 *prep_elem, u32 metric)
678 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
679 struct mesh_path *mpath;
680 const u8 *target_addr, *orig_addr;
681 u8 ttl, hopcount, flags;
682 u8 next_hop[ETH_ALEN];
683 u32 target_sn, orig_sn, lifetime;
685 mhwmp_dbg(sdata, "received PREP from %pM\n",
686 PREP_IE_TARGET_ADDR(prep_elem));
688 orig_addr = PREP_IE_ORIG_ADDR(prep_elem);
689 if (ether_addr_equal(orig_addr, sdata->vif.addr))
690 /* destination, no forwarding required */
693 if (!ifmsh->mshcfg.dot11MeshForwarding)
696 ttl = PREP_IE_TTL(prep_elem);
698 sdata->u.mesh.mshstats.dropped_frames_ttl++;
703 mpath = mesh_path_lookup(sdata, orig_addr);
705 spin_lock_bh(&mpath->state_lock);
708 if (!(mpath->flags & MESH_PATH_ACTIVE)) {
709 spin_unlock_bh(&mpath->state_lock);
712 memcpy(next_hop, next_hop_deref_protected(mpath)->sta.addr, ETH_ALEN);
713 spin_unlock_bh(&mpath->state_lock);
715 flags = PREP_IE_FLAGS(prep_elem);
716 lifetime = PREP_IE_LIFETIME(prep_elem);
717 hopcount = PREP_IE_HOPCOUNT(prep_elem) + 1;
718 target_addr = PREP_IE_TARGET_ADDR(prep_elem);
719 target_sn = PREP_IE_TARGET_SN(prep_elem);
720 orig_sn = PREP_IE_ORIG_SN(prep_elem);
722 mesh_path_sel_frame_tx(MPATH_PREP, flags, orig_addr, orig_sn, 0,
723 target_addr, target_sn, next_hop, hopcount,
724 ttl, lifetime, metric, 0, sdata);
727 sdata->u.mesh.mshstats.fwded_unicast++;
728 sdata->u.mesh.mshstats.fwded_frames++;
733 sdata->u.mesh.mshstats.dropped_frames_no_route++;
736 static void hwmp_perr_frame_process(struct ieee80211_sub_if_data *sdata,
737 struct ieee80211_mgmt *mgmt,
740 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
741 struct mesh_path *mpath;
743 const u8 *ta, *target_addr;
748 ttl = PERR_IE_TTL(perr_elem);
750 ifmsh->mshstats.dropped_frames_ttl++;
754 target_addr = PERR_IE_TARGET_ADDR(perr_elem);
755 target_sn = PERR_IE_TARGET_SN(perr_elem);
756 target_rcode = PERR_IE_TARGET_RCODE(perr_elem);
759 mpath = mesh_path_lookup(sdata, target_addr);
761 struct sta_info *sta;
763 spin_lock_bh(&mpath->state_lock);
764 sta = next_hop_deref_protected(mpath);
765 if (mpath->flags & MESH_PATH_ACTIVE &&
766 ether_addr_equal(ta, sta->sta.addr) &&
767 !(mpath->flags & MESH_PATH_FIXED) &&
768 (!(mpath->flags & MESH_PATH_SN_VALID) ||
769 SN_GT(target_sn, mpath->sn) || target_sn == 0)) {
770 mpath->flags &= ~MESH_PATH_ACTIVE;
772 mpath->sn = target_sn;
775 spin_unlock_bh(&mpath->state_lock);
776 if (!ifmsh->mshcfg.dot11MeshForwarding)
778 mesh_path_error_tx(sdata, ttl, target_addr,
779 target_sn, target_rcode,
782 spin_unlock_bh(&mpath->state_lock);
788 static void hwmp_rann_frame_process(struct ieee80211_sub_if_data *sdata,
789 struct ieee80211_mgmt *mgmt,
790 const struct ieee80211_rann_ie *rann)
792 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
793 struct ieee80211_local *local = sdata->local;
794 struct sta_info *sta;
795 struct mesh_path *mpath;
796 u8 ttl, flags, hopcount;
798 u32 orig_sn, new_metric, orig_metric, last_hop_metric, interval;
801 ttl = rann->rann_ttl;
802 flags = rann->rann_flags;
803 root_is_gate = !!(flags & RANN_FLAG_IS_GATE);
804 orig_addr = rann->rann_addr;
805 orig_sn = le32_to_cpu(rann->rann_seq);
806 interval = le32_to_cpu(rann->rann_interval);
807 hopcount = rann->rann_hopcount;
809 orig_metric = le32_to_cpu(rann->rann_metric);
811 /* Ignore our own RANNs */
812 if (ether_addr_equal(orig_addr, sdata->vif.addr))
816 "received RANN from %pM via neighbour %pM (is_gate=%d)\n",
817 orig_addr, mgmt->sa, root_is_gate);
820 sta = sta_info_get(sdata, mgmt->sa);
826 last_hop_metric = airtime_link_metric_get(local, sta);
827 new_metric = orig_metric + last_hop_metric;
828 if (new_metric < orig_metric)
829 new_metric = MAX_METRIC;
831 mpath = mesh_path_lookup(sdata, orig_addr);
833 mpath = mesh_path_add(sdata, orig_addr);
836 sdata->u.mesh.mshstats.dropped_frames_no_route++;
841 if (!(SN_LT(mpath->sn, orig_sn)) &&
842 !(mpath->sn == orig_sn && new_metric < mpath->rann_metric)) {
847 if ((!(mpath->flags & (MESH_PATH_ACTIVE | MESH_PATH_RESOLVING)) ||
848 (time_after(jiffies, mpath->last_preq_to_root +
849 root_path_confirmation_jiffies(sdata)) ||
850 time_before(jiffies, mpath->last_preq_to_root))) &&
851 !(mpath->flags & MESH_PATH_FIXED) && (ttl != 0)) {
853 "time to refresh root mpath %pM\n",
855 mesh_queue_preq(mpath, PREQ_Q_F_START | PREQ_Q_F_REFRESH);
856 mpath->last_preq_to_root = jiffies;
860 mpath->rann_metric = new_metric;
861 mpath->is_root = true;
862 /* Recording RANNs sender address to send individually
863 * addressed PREQs destined for root mesh STA */
864 memcpy(mpath->rann_snd_addr, mgmt->sa, ETH_ALEN);
867 mesh_path_add_gate(mpath);
870 ifmsh->mshstats.dropped_frames_ttl++;
876 if (ifmsh->mshcfg.dot11MeshForwarding) {
877 mesh_path_sel_frame_tx(MPATH_RANN, flags, orig_addr,
878 orig_sn, 0, NULL, 0, broadcast_addr,
879 hopcount, ttl, interval,
880 new_metric, 0, sdata);
887 void mesh_rx_path_sel_frame(struct ieee80211_sub_if_data *sdata,
888 struct ieee80211_mgmt *mgmt, size_t len)
890 struct ieee802_11_elems elems;
893 struct sta_info *sta;
895 /* need action_code */
896 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
900 sta = sta_info_get(sdata, mgmt->sa);
901 if (!sta || sta->mesh->plink_state != NL80211_PLINK_ESTAB) {
907 baselen = (u8 *) mgmt->u.action.u.mesh_action.variable - (u8 *) mgmt;
908 ieee802_11_parse_elems(mgmt->u.action.u.mesh_action.variable,
909 len - baselen, false, &elems);
912 if (elems.preq_len != 37)
913 /* Right now we support just 1 destination and no AE */
915 path_metric = hwmp_route_info_get(sdata, mgmt, elems.preq,
918 hwmp_preq_frame_process(sdata, mgmt, elems.preq,
922 if (elems.prep_len != 31)
923 /* Right now we support no AE */
925 path_metric = hwmp_route_info_get(sdata, mgmt, elems.prep,
928 hwmp_prep_frame_process(sdata, mgmt, elems.prep,
932 if (elems.perr_len != 15)
933 /* Right now we support only one destination per PERR */
935 hwmp_perr_frame_process(sdata, mgmt, elems.perr);
938 hwmp_rann_frame_process(sdata, mgmt, elems.rann);
942 * mesh_queue_preq - queue a PREQ to a given destination
944 * @mpath: mesh path to discover
945 * @flags: special attributes of the PREQ to be sent
947 * Locking: the function must be called from within a rcu read lock block.
950 static void mesh_queue_preq(struct mesh_path *mpath, u8 flags)
952 struct ieee80211_sub_if_data *sdata = mpath->sdata;
953 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
954 struct mesh_preq_queue *preq_node;
956 preq_node = kmalloc(sizeof(struct mesh_preq_queue), GFP_ATOMIC);
958 mhwmp_dbg(sdata, "could not allocate PREQ node\n");
962 spin_lock_bh(&ifmsh->mesh_preq_queue_lock);
963 if (ifmsh->preq_queue_len == MAX_PREQ_QUEUE_LEN) {
964 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
966 if (printk_ratelimit())
967 mhwmp_dbg(sdata, "PREQ node queue full\n");
971 spin_lock(&mpath->state_lock);
972 if (mpath->flags & MESH_PATH_REQ_QUEUED) {
973 spin_unlock(&mpath->state_lock);
974 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
979 memcpy(preq_node->dst, mpath->dst, ETH_ALEN);
980 preq_node->flags = flags;
982 mpath->flags |= MESH_PATH_REQ_QUEUED;
983 spin_unlock(&mpath->state_lock);
985 list_add_tail(&preq_node->list, &ifmsh->preq_queue.list);
986 ++ifmsh->preq_queue_len;
987 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
989 if (time_after(jiffies, ifmsh->last_preq + min_preq_int_jiff(sdata)))
990 ieee80211_queue_work(&sdata->local->hw, &sdata->work);
992 else if (time_before(jiffies, ifmsh->last_preq)) {
993 /* avoid long wait if did not send preqs for a long time
994 * and jiffies wrapped around
996 ifmsh->last_preq = jiffies - min_preq_int_jiff(sdata) - 1;
997 ieee80211_queue_work(&sdata->local->hw, &sdata->work);
999 mod_timer(&ifmsh->mesh_path_timer, ifmsh->last_preq +
1000 min_preq_int_jiff(sdata));
1004 * mesh_path_start_discovery - launch a path discovery from the PREQ queue
1006 * @sdata: local mesh subif
1008 void mesh_path_start_discovery(struct ieee80211_sub_if_data *sdata)
1010 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1011 struct mesh_preq_queue *preq_node;
1012 struct mesh_path *mpath;
1013 u8 ttl, target_flags = 0;
1017 spin_lock_bh(&ifmsh->mesh_preq_queue_lock);
1018 if (!ifmsh->preq_queue_len ||
1019 time_before(jiffies, ifmsh->last_preq +
1020 min_preq_int_jiff(sdata))) {
1021 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
1025 preq_node = list_first_entry(&ifmsh->preq_queue.list,
1026 struct mesh_preq_queue, list);
1027 list_del(&preq_node->list);
1028 --ifmsh->preq_queue_len;
1029 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
1032 mpath = mesh_path_lookup(sdata, preq_node->dst);
1036 spin_lock_bh(&mpath->state_lock);
1037 if (mpath->flags & (MESH_PATH_DELETED | MESH_PATH_FIXED)) {
1038 spin_unlock_bh(&mpath->state_lock);
1041 mpath->flags &= ~MESH_PATH_REQ_QUEUED;
1042 if (preq_node->flags & PREQ_Q_F_START) {
1043 if (mpath->flags & MESH_PATH_RESOLVING) {
1044 spin_unlock_bh(&mpath->state_lock);
1047 mpath->flags &= ~MESH_PATH_RESOLVED;
1048 mpath->flags |= MESH_PATH_RESOLVING;
1049 mpath->discovery_retries = 0;
1050 mpath->discovery_timeout = disc_timeout_jiff(sdata);
1052 } else if (!(mpath->flags & MESH_PATH_RESOLVING) ||
1053 mpath->flags & MESH_PATH_RESOLVED) {
1054 mpath->flags &= ~MESH_PATH_RESOLVING;
1055 spin_unlock_bh(&mpath->state_lock);
1059 ifmsh->last_preq = jiffies;
1061 if (time_after(jiffies, ifmsh->last_sn_update +
1062 net_traversal_jiffies(sdata)) ||
1063 time_before(jiffies, ifmsh->last_sn_update)) {
1065 sdata->u.mesh.last_sn_update = jiffies;
1067 lifetime = default_lifetime(sdata);
1068 ttl = sdata->u.mesh.mshcfg.element_ttl;
1070 sdata->u.mesh.mshstats.dropped_frames_ttl++;
1071 spin_unlock_bh(&mpath->state_lock);
1075 if (preq_node->flags & PREQ_Q_F_REFRESH)
1076 target_flags |= IEEE80211_PREQ_TO_FLAG;
1078 target_flags &= ~IEEE80211_PREQ_TO_FLAG;
1080 spin_unlock_bh(&mpath->state_lock);
1081 da = (mpath->is_root) ? mpath->rann_snd_addr : broadcast_addr;
1082 mesh_path_sel_frame_tx(MPATH_PREQ, 0, sdata->vif.addr, ifmsh->sn,
1083 target_flags, mpath->dst, mpath->sn, da, 0,
1084 ttl, lifetime, 0, ifmsh->preq_id++, sdata);
1086 spin_lock_bh(&mpath->state_lock);
1087 if (mpath->flags & MESH_PATH_DELETED) {
1088 spin_unlock_bh(&mpath->state_lock);
1091 mod_timer(&mpath->timer, jiffies + mpath->discovery_timeout);
1092 spin_unlock_bh(&mpath->state_lock);
1100 * mesh_nexthop_resolve - lookup next hop; conditionally start path discovery
1102 * @skb: 802.11 frame to be sent
1103 * @sdata: network subif the frame will be sent through
1105 * Lookup next hop for given skb and start path discovery if no
1106 * forwarding information is found.
1108 * Returns: 0 if the next hop was found and -ENOENT if the frame was queued.
1109 * skb is freeed here if no mpath could be allocated.
1111 int mesh_nexthop_resolve(struct ieee80211_sub_if_data *sdata,
1112 struct sk_buff *skb)
1114 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1115 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1116 struct mesh_path *mpath;
1117 struct sk_buff *skb_to_free = NULL;
1118 u8 *target_addr = hdr->addr3;
1121 /* Nulls are only sent to peers for PS and should be pre-addressed */
1122 if (ieee80211_is_qos_nullfunc(hdr->frame_control))
1126 err = mesh_nexthop_lookup(sdata, skb);
1130 /* no nexthop found, start resolving */
1131 mpath = mesh_path_lookup(sdata, target_addr);
1133 mpath = mesh_path_add(sdata, target_addr);
1134 if (IS_ERR(mpath)) {
1135 mesh_path_discard_frame(sdata, skb);
1136 err = PTR_ERR(mpath);
1141 if (!(mpath->flags & MESH_PATH_RESOLVING) &&
1142 mesh_path_sel_is_hwmp(sdata))
1143 mesh_queue_preq(mpath, PREQ_Q_F_START);
1145 if (skb_queue_len(&mpath->frame_queue) >= MESH_FRAME_QUEUE_LEN)
1146 skb_to_free = skb_dequeue(&mpath->frame_queue);
1148 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1149 ieee80211_set_qos_hdr(sdata, skb);
1150 skb_queue_tail(&mpath->frame_queue, skb);
1153 mesh_path_discard_frame(sdata, skb_to_free);
1161 * mesh_nexthop_lookup - put the appropriate next hop on a mesh frame. Calling
1162 * this function is considered "using" the associated mpath, so preempt a path
1163 * refresh if this mpath expires soon.
1165 * @skb: 802.11 frame to be sent
1166 * @sdata: network subif the frame will be sent through
1168 * Returns: 0 if the next hop was found. Nonzero otherwise.
1170 int mesh_nexthop_lookup(struct ieee80211_sub_if_data *sdata,
1171 struct sk_buff *skb)
1173 struct mesh_path *mpath;
1174 struct sta_info *next_hop;
1175 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1176 u8 *target_addr = hdr->addr3;
1180 mpath = mesh_path_lookup(sdata, target_addr);
1182 if (!mpath || !(mpath->flags & MESH_PATH_ACTIVE))
1185 if (time_after(jiffies,
1187 msecs_to_jiffies(sdata->u.mesh.mshcfg.path_refresh_time)) &&
1188 ether_addr_equal(sdata->vif.addr, hdr->addr4) &&
1189 !(mpath->flags & MESH_PATH_RESOLVING) &&
1190 !(mpath->flags & MESH_PATH_FIXED))
1191 mesh_queue_preq(mpath, PREQ_Q_F_START | PREQ_Q_F_REFRESH);
1193 next_hop = rcu_dereference(mpath->next_hop);
1195 memcpy(hdr->addr1, next_hop->sta.addr, ETH_ALEN);
1196 memcpy(hdr->addr2, sdata->vif.addr, ETH_ALEN);
1197 ieee80211_mps_set_frame_flags(sdata, next_hop, hdr);
1206 void mesh_path_timer(unsigned long data)
1208 struct mesh_path *mpath = (void *) data;
1209 struct ieee80211_sub_if_data *sdata = mpath->sdata;
1212 if (sdata->local->quiescing)
1215 spin_lock_bh(&mpath->state_lock);
1216 if (mpath->flags & MESH_PATH_RESOLVED ||
1217 (!(mpath->flags & MESH_PATH_RESOLVING))) {
1218 mpath->flags &= ~(MESH_PATH_RESOLVING | MESH_PATH_RESOLVED);
1219 spin_unlock_bh(&mpath->state_lock);
1220 } else if (mpath->discovery_retries < max_preq_retries(sdata)) {
1221 ++mpath->discovery_retries;
1222 mpath->discovery_timeout *= 2;
1223 mpath->flags &= ~MESH_PATH_REQ_QUEUED;
1224 spin_unlock_bh(&mpath->state_lock);
1225 mesh_queue_preq(mpath, 0);
1227 mpath->flags &= ~(MESH_PATH_RESOLVING |
1228 MESH_PATH_RESOLVED |
1229 MESH_PATH_REQ_QUEUED);
1230 mpath->exp_time = jiffies;
1231 spin_unlock_bh(&mpath->state_lock);
1232 if (!mpath->is_gate && mesh_gate_num(sdata) > 0) {
1233 ret = mesh_path_send_to_gates(mpath);
1235 mhwmp_dbg(sdata, "no gate was reachable\n");
1237 mesh_path_flush_pending(mpath);
1241 void mesh_path_tx_root_frame(struct ieee80211_sub_if_data *sdata)
1243 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1244 u32 interval = ifmsh->mshcfg.dot11MeshHWMPRannInterval;
1245 u8 flags, target_flags = 0;
1247 flags = (ifmsh->mshcfg.dot11MeshGateAnnouncementProtocol)
1248 ? RANN_FLAG_IS_GATE : 0;
1250 switch (ifmsh->mshcfg.dot11MeshHWMPRootMode) {
1251 case IEEE80211_PROACTIVE_RANN:
1252 mesh_path_sel_frame_tx(MPATH_RANN, flags, sdata->vif.addr,
1253 ++ifmsh->sn, 0, NULL, 0, broadcast_addr,
1254 0, ifmsh->mshcfg.element_ttl,
1255 interval, 0, 0, sdata);
1257 case IEEE80211_PROACTIVE_PREQ_WITH_PREP:
1258 flags |= IEEE80211_PREQ_PROACTIVE_PREP_FLAG;
1259 case IEEE80211_PROACTIVE_PREQ_NO_PREP:
1260 interval = ifmsh->mshcfg.dot11MeshHWMPactivePathToRootTimeout;
1261 target_flags |= IEEE80211_PREQ_TO_FLAG |
1262 IEEE80211_PREQ_USN_FLAG;
1263 mesh_path_sel_frame_tx(MPATH_PREQ, flags, sdata->vif.addr,
1264 ++ifmsh->sn, target_flags,
1265 (u8 *) broadcast_addr, 0, broadcast_addr,
1266 0, ifmsh->mshcfg.element_ttl, interval,
1267 0, ifmsh->preq_id++, sdata);
1270 mhwmp_dbg(sdata, "Proactive mechanism not supported\n");