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 /* Number of frames buffered per destination for unresolved destinations */
21 #define MESH_FRAME_QUEUE_LEN 10
22 #define MAX_PREQ_QUEUE_LEN 64
24 /* Destination only */
26 /* Reply and forward */
28 /* Unknown Sequence Number */
30 /* Reason code Present */
31 #define MP_F_RCODE 0x02
33 static void mesh_queue_preq(struct mesh_path *, u8);
35 static inline u32 u32_field_get(u8 *preq_elem, int offset, bool ae)
39 return get_unaligned_le32(preq_elem + offset);
42 static inline u32 u16_field_get(u8 *preq_elem, int offset, bool ae)
46 return get_unaligned_le16(preq_elem + offset);
49 /* HWMP IE processing macros */
51 #define AE_F_SET(x) (*x & AE_F)
52 #define PREQ_IE_FLAGS(x) (*(x))
53 #define PREQ_IE_HOPCOUNT(x) (*(x + 1))
54 #define PREQ_IE_TTL(x) (*(x + 2))
55 #define PREQ_IE_PREQ_ID(x) u32_field_get(x, 3, 0)
56 #define PREQ_IE_ORIG_ADDR(x) (x + 7)
57 #define PREQ_IE_ORIG_SN(x) u32_field_get(x, 13, 0)
58 #define PREQ_IE_LIFETIME(x) u32_field_get(x, 17, AE_F_SET(x))
59 #define PREQ_IE_METRIC(x) u32_field_get(x, 21, AE_F_SET(x))
60 #define PREQ_IE_TARGET_F(x) (*(AE_F_SET(x) ? x + 32 : x + 26))
61 #define PREQ_IE_TARGET_ADDR(x) (AE_F_SET(x) ? x + 33 : x + 27)
62 #define PREQ_IE_TARGET_SN(x) u32_field_get(x, 33, AE_F_SET(x))
65 #define PREP_IE_FLAGS(x) PREQ_IE_FLAGS(x)
66 #define PREP_IE_HOPCOUNT(x) PREQ_IE_HOPCOUNT(x)
67 #define PREP_IE_TTL(x) PREQ_IE_TTL(x)
68 #define PREP_IE_ORIG_ADDR(x) (AE_F_SET(x) ? x + 27 : x + 21)
69 #define PREP_IE_ORIG_SN(x) u32_field_get(x, 27, AE_F_SET(x))
70 #define PREP_IE_LIFETIME(x) u32_field_get(x, 13, AE_F_SET(x))
71 #define PREP_IE_METRIC(x) u32_field_get(x, 17, AE_F_SET(x))
72 #define PREP_IE_TARGET_ADDR(x) (x + 3)
73 #define PREP_IE_TARGET_SN(x) u32_field_get(x, 9, 0)
75 #define PERR_IE_TTL(x) (*(x))
76 #define PERR_IE_TARGET_FLAGS(x) (*(x + 2))
77 #define PERR_IE_TARGET_ADDR(x) (x + 3)
78 #define PERR_IE_TARGET_SN(x) u32_field_get(x, 9, 0)
79 #define PERR_IE_TARGET_RCODE(x) u16_field_get(x, 13, 0)
81 #define MSEC_TO_TU(x) (x*1000/1024)
82 #define SN_GT(x, y) ((s32)(y - x) < 0)
83 #define SN_LT(x, y) ((s32)(x - y) < 0)
85 #define net_traversal_jiffies(s) \
86 msecs_to_jiffies(s->u.mesh.mshcfg.dot11MeshHWMPnetDiameterTraversalTime)
87 #define default_lifetime(s) \
88 MSEC_TO_TU(s->u.mesh.mshcfg.dot11MeshHWMPactivePathTimeout)
89 #define min_preq_int_jiff(s) \
90 (msecs_to_jiffies(s->u.mesh.mshcfg.dot11MeshHWMPpreqMinInterval))
91 #define max_preq_retries(s) (s->u.mesh.mshcfg.dot11MeshHWMPmaxPREQretries)
92 #define disc_timeout_jiff(s) \
93 msecs_to_jiffies(sdata->u.mesh.mshcfg.min_discovery_timeout)
94 #define root_path_confirmation_jiffies(s) \
95 msecs_to_jiffies(sdata->u.mesh.mshcfg.dot11MeshHWMPconfirmationInterval)
97 enum mpath_frame_type {
104 static const u8 broadcast_addr[ETH_ALEN] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
106 static int mesh_path_sel_frame_tx(enum mpath_frame_type action, u8 flags,
107 u8 *orig_addr, __le32 orig_sn, u8 target_flags, u8 *target,
108 __le32 target_sn, const u8 *da, u8 hop_count, u8 ttl,
109 __le32 lifetime, __le32 metric, __le32 preq_id,
110 struct ieee80211_sub_if_data *sdata)
112 struct ieee80211_local *local = sdata->local;
114 struct ieee80211_mgmt *mgmt;
116 int hdr_len = offsetof(struct ieee80211_mgmt, u.action.u.mesh_action) +
117 sizeof(mgmt->u.action.u.mesh_action);
119 skb = dev_alloc_skb(local->tx_headroom +
121 2 + 37); /* max HWMP IE */
124 skb_reserve(skb, local->tx_headroom);
125 mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len);
126 memset(mgmt, 0, hdr_len);
127 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
128 IEEE80211_STYPE_ACTION);
130 memcpy(mgmt->da, da, ETH_ALEN);
131 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
133 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
134 mgmt->u.action.category = WLAN_CATEGORY_MESH_ACTION;
135 mgmt->u.action.u.mesh_action.action_code =
136 WLAN_MESH_ACTION_HWMP_PATH_SELECTION;
140 mhwmp_dbg(sdata, "sending PREQ to %pM\n", target);
142 pos = skb_put(skb, 2 + ie_len);
143 *pos++ = WLAN_EID_PREQ;
146 mhwmp_dbg(sdata, "sending PREP to %pM\n", target);
148 pos = skb_put(skb, 2 + ie_len);
149 *pos++ = WLAN_EID_PREP;
152 mhwmp_dbg(sdata, "sending RANN from %pM\n", orig_addr);
153 ie_len = sizeof(struct ieee80211_rann_ie);
154 pos = skb_put(skb, 2 + ie_len);
155 *pos++ = WLAN_EID_RANN;
166 if (action == MPATH_PREP) {
167 memcpy(pos, target, ETH_ALEN);
169 memcpy(pos, &target_sn, 4);
172 if (action == MPATH_PREQ) {
173 memcpy(pos, &preq_id, 4);
176 memcpy(pos, orig_addr, ETH_ALEN);
178 memcpy(pos, &orig_sn, 4);
181 memcpy(pos, &lifetime, 4); /* interval for RANN */
183 memcpy(pos, &metric, 4);
185 if (action == MPATH_PREQ) {
186 *pos++ = 1; /* destination count */
187 *pos++ = target_flags;
188 memcpy(pos, target, ETH_ALEN);
190 memcpy(pos, &target_sn, 4);
192 } else if (action == MPATH_PREP) {
193 memcpy(pos, orig_addr, ETH_ALEN);
195 memcpy(pos, &orig_sn, 4);
199 ieee80211_tx_skb(sdata, skb);
204 /* Headroom is not adjusted. Caller should ensure that skb has sufficient
205 * headroom in case the frame is encrypted. */
206 static void prepare_frame_for_deferred_tx(struct ieee80211_sub_if_data *sdata,
209 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
211 skb_set_mac_header(skb, 0);
212 skb_set_network_header(skb, 0);
213 skb_set_transport_header(skb, 0);
215 /* Send all internal mgmt frames on VO. Accordingly set TID to 7. */
216 skb_set_queue_mapping(skb, IEEE80211_AC_VO);
219 info->control.vif = &sdata->vif;
220 ieee80211_set_qos_hdr(sdata, skb);
224 * mesh_send_path error - Sends a PERR mesh management frame
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
231 * Note: This function may be called with driver locks taken that the driver
232 * also acquires in the TX path. To avoid a deadlock we don't transmit the
233 * frame directly but add it to the pending queue instead.
235 int mesh_path_error_tx(u8 ttl, u8 *target, __le32 target_sn,
236 __le16 target_rcode, const u8 *ra,
237 struct ieee80211_sub_if_data *sdata)
239 struct ieee80211_local *local = sdata->local;
241 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
242 struct ieee80211_mgmt *mgmt;
244 int hdr_len = offsetof(struct ieee80211_mgmt, u.action.u.mesh_action) +
245 sizeof(mgmt->u.action.u.mesh_action);
247 if (time_before(jiffies, ifmsh->next_perr))
250 skb = dev_alloc_skb(local->tx_headroom +
252 2 + 15 /* PERR IE */);
255 skb_reserve(skb, local->tx_headroom);
256 mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len);
257 memset(mgmt, 0, hdr_len);
258 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
259 IEEE80211_STYPE_ACTION);
261 memcpy(mgmt->da, ra, ETH_ALEN);
262 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
264 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
265 mgmt->u.action.category = WLAN_CATEGORY_MESH_ACTION;
266 mgmt->u.action.u.mesh_action.action_code =
267 WLAN_MESH_ACTION_HWMP_PATH_SELECTION;
269 pos = skb_put(skb, 2 + ie_len);
270 *pos++ = WLAN_EID_PERR;
274 /* number of destinations */
277 * flags bit, bit 1 is unset if we know the sequence number and
278 * bit 2 is set if we have a reason code
286 memcpy(pos, target, ETH_ALEN);
288 memcpy(pos, &target_sn, 4);
290 memcpy(pos, &target_rcode, 2);
292 /* see note in function header */
293 prepare_frame_for_deferred_tx(sdata, skb);
294 ifmsh->next_perr = TU_TO_EXP_TIME(
295 ifmsh->mshcfg.dot11MeshHWMPperrMinInterval);
296 ieee80211_add_pending_skb(local, skb);
300 void ieee80211s_update_metric(struct ieee80211_local *local,
301 struct sta_info *sta, struct sk_buff *skb)
303 struct ieee80211_tx_info *txinfo = IEEE80211_SKB_CB(skb);
304 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
307 if (!ieee80211_is_data(hdr->frame_control))
310 failed = !(txinfo->flags & IEEE80211_TX_STAT_ACK);
312 /* moving average, scaled to 100 */
313 sta->fail_avg = ((80 * sta->fail_avg + 5) / 100 + 20 * failed);
314 if (sta->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;
330 if (sta->fail_avg >= 100)
333 sta_set_rate_info_tx(sta, &sta->last_tx_rate, &rinfo);
334 rate = cfg80211_calculate_bitrate(&rinfo);
338 err = (sta->fail_avg << ARITH_SHIFT) / 100;
340 /* bitrate is in units of 100 Kbps, while we need rate in units of
341 * 1Mbps. This will be corrected on tx_time computation.
343 tx_time = (device_constant + 10 * test_frame_len / rate);
344 estimated_retx = ((1 << (2 * ARITH_SHIFT)) / (s_unit - err));
345 result = (tx_time * estimated_retx) >> (2 * ARITH_SHIFT) ;
350 * hwmp_route_info_get - Update routing info to originator and transmitter
352 * @sdata: local mesh subif
353 * @mgmt: mesh management frame
354 * @hwmp_ie: hwmp information element (PREP or PREQ)
356 * This function updates the path routing information to the originator and the
357 * transmitter of a HWMP PREQ or PREP frame.
359 * Returns: metric to frame originator or 0 if the frame should not be further
362 * Notes: this function is the only place (besides user-provided info) where
363 * path routing information is updated.
365 static u32 hwmp_route_info_get(struct ieee80211_sub_if_data *sdata,
366 struct ieee80211_mgmt *mgmt,
367 u8 *hwmp_ie, enum mpath_frame_type action)
369 struct ieee80211_local *local = sdata->local;
370 struct mesh_path *mpath;
371 struct sta_info *sta;
374 u32 orig_sn, orig_metric;
375 unsigned long orig_lifetime, exp_time;
376 u32 last_hop_metric, new_metric;
380 sta = sta_info_get(sdata, mgmt->sa);
386 last_hop_metric = airtime_link_metric_get(local, sta);
387 /* Update and check originator routing info */
392 orig_addr = PREQ_IE_ORIG_ADDR(hwmp_ie);
393 orig_sn = PREQ_IE_ORIG_SN(hwmp_ie);
394 orig_lifetime = PREQ_IE_LIFETIME(hwmp_ie);
395 orig_metric = PREQ_IE_METRIC(hwmp_ie);
398 /* Originator here refers to the MP that was the target in the
399 * Path Request. We divert from the nomenclature in the draft
400 * so that we can easily use a single function to gather path
401 * information from both PREQ and PREP frames.
403 orig_addr = PREP_IE_TARGET_ADDR(hwmp_ie);
404 orig_sn = PREP_IE_TARGET_SN(hwmp_ie);
405 orig_lifetime = PREP_IE_LIFETIME(hwmp_ie);
406 orig_metric = PREP_IE_METRIC(hwmp_ie);
412 new_metric = orig_metric + last_hop_metric;
413 if (new_metric < orig_metric)
414 new_metric = MAX_METRIC;
415 exp_time = TU_TO_EXP_TIME(orig_lifetime);
417 if (ether_addr_equal(orig_addr, sdata->vif.addr)) {
418 /* This MP is the originator, we are not interested in this
419 * frame, except for updating transmitter's path info.
424 mpath = mesh_path_lookup(orig_addr, sdata);
426 spin_lock_bh(&mpath->state_lock);
427 if (mpath->flags & MESH_PATH_FIXED)
429 else if ((mpath->flags & MESH_PATH_ACTIVE) &&
430 (mpath->flags & MESH_PATH_SN_VALID)) {
431 if (SN_GT(mpath->sn, orig_sn) ||
432 (mpath->sn == orig_sn &&
433 new_metric >= mpath->metric)) {
439 mesh_path_add(orig_addr, sdata);
440 mpath = mesh_path_lookup(orig_addr, sdata);
445 spin_lock_bh(&mpath->state_lock);
449 mesh_path_assign_nexthop(mpath, sta);
450 mpath->flags |= MESH_PATH_SN_VALID;
451 mpath->metric = new_metric;
453 mpath->exp_time = time_after(mpath->exp_time, exp_time)
454 ? mpath->exp_time : exp_time;
455 mesh_path_activate(mpath);
456 spin_unlock_bh(&mpath->state_lock);
457 mesh_path_tx_pending(mpath);
458 /* draft says preq_id should be saved to, but there does
459 * not seem to be any use for it, skipping by now
462 spin_unlock_bh(&mpath->state_lock);
465 /* Update and check transmitter routing info */
467 if (ether_addr_equal(orig_addr, ta))
472 mpath = mesh_path_lookup(ta, sdata);
474 spin_lock_bh(&mpath->state_lock);
475 if ((mpath->flags & MESH_PATH_FIXED) ||
476 ((mpath->flags & MESH_PATH_ACTIVE) &&
477 (last_hop_metric > mpath->metric)))
480 mesh_path_add(ta, sdata);
481 mpath = mesh_path_lookup(ta, sdata);
486 spin_lock_bh(&mpath->state_lock);
490 mesh_path_assign_nexthop(mpath, sta);
491 mpath->metric = last_hop_metric;
492 mpath->exp_time = time_after(mpath->exp_time, exp_time)
493 ? mpath->exp_time : exp_time;
494 mesh_path_activate(mpath);
495 spin_unlock_bh(&mpath->state_lock);
496 mesh_path_tx_pending(mpath);
498 spin_unlock_bh(&mpath->state_lock);
503 return process ? new_metric : 0;
506 static void hwmp_preq_frame_process(struct ieee80211_sub_if_data *sdata,
507 struct ieee80211_mgmt *mgmt,
508 u8 *preq_elem, u32 metric)
510 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
511 struct mesh_path *mpath = NULL;
512 u8 *target_addr, *orig_addr;
514 u8 target_flags, ttl, flags;
515 u32 orig_sn, target_sn, lifetime, orig_metric;
520 /* Update target SN, if present */
521 target_addr = PREQ_IE_TARGET_ADDR(preq_elem);
522 orig_addr = PREQ_IE_ORIG_ADDR(preq_elem);
523 target_sn = PREQ_IE_TARGET_SN(preq_elem);
524 orig_sn = PREQ_IE_ORIG_SN(preq_elem);
525 target_flags = PREQ_IE_TARGET_F(preq_elem);
526 orig_metric = metric;
527 /* Proactive PREQ gate announcements */
528 flags = PREQ_IE_FLAGS(preq_elem);
529 root_is_gate = !!(flags & RANN_FLAG_IS_GATE);
531 mhwmp_dbg(sdata, "received PREQ from %pM\n", orig_addr);
533 if (ether_addr_equal(target_addr, sdata->vif.addr)) {
534 mhwmp_dbg(sdata, "PREQ is for us\n");
538 if (time_after(jiffies, ifmsh->last_sn_update +
539 net_traversal_jiffies(sdata)) ||
540 time_before(jiffies, ifmsh->last_sn_update)) {
541 target_sn = ++ifmsh->sn;
542 ifmsh->last_sn_update = jiffies;
544 } else if (is_broadcast_ether_addr(target_addr) &&
545 (target_flags & IEEE80211_PREQ_TO_FLAG)) {
547 mpath = mesh_path_lookup(orig_addr, sdata);
549 if (flags & IEEE80211_PREQ_PROACTIVE_PREP_FLAG) {
551 target_addr = sdata->vif.addr;
552 target_sn = ++ifmsh->sn;
554 ifmsh->last_sn_update = jiffies;
557 mesh_path_add_gate(mpath);
562 mpath = mesh_path_lookup(target_addr, sdata);
564 if ((!(mpath->flags & MESH_PATH_SN_VALID)) ||
565 SN_LT(mpath->sn, target_sn)) {
566 mpath->sn = target_sn;
567 mpath->flags |= MESH_PATH_SN_VALID;
568 } else if ((!(target_flags & MP_F_DO)) &&
569 (mpath->flags & MESH_PATH_ACTIVE)) {
571 metric = mpath->metric;
572 target_sn = mpath->sn;
573 if (target_flags & MP_F_RF)
574 target_flags |= MP_F_DO;
583 lifetime = PREQ_IE_LIFETIME(preq_elem);
584 ttl = ifmsh->mshcfg.element_ttl;
586 mhwmp_dbg(sdata, "replying to the PREQ\n");
587 mesh_path_sel_frame_tx(MPATH_PREP, 0, orig_addr,
588 cpu_to_le32(orig_sn), 0, target_addr,
589 cpu_to_le32(target_sn), mgmt->sa, 0, ttl,
590 cpu_to_le32(lifetime), cpu_to_le32(metric),
593 ifmsh->mshstats.dropped_frames_ttl++;
597 if (forward && ifmsh->mshcfg.dot11MeshForwarding) {
601 ttl = PREQ_IE_TTL(preq_elem);
602 lifetime = PREQ_IE_LIFETIME(preq_elem);
604 ifmsh->mshstats.dropped_frames_ttl++;
607 mhwmp_dbg(sdata, "forwarding the PREQ from %pM\n", orig_addr);
609 preq_id = PREQ_IE_PREQ_ID(preq_elem);
610 hopcount = PREQ_IE_HOPCOUNT(preq_elem) + 1;
611 da = (mpath && mpath->is_root) ?
612 mpath->rann_snd_addr : broadcast_addr;
614 if (flags & IEEE80211_PREQ_PROACTIVE_PREP_FLAG) {
615 target_addr = PREQ_IE_TARGET_ADDR(preq_elem);
616 target_sn = PREQ_IE_TARGET_SN(preq_elem);
617 metric = orig_metric;
620 mesh_path_sel_frame_tx(MPATH_PREQ, flags, orig_addr,
621 cpu_to_le32(orig_sn), target_flags, target_addr,
622 cpu_to_le32(target_sn), da,
623 hopcount, ttl, cpu_to_le32(lifetime),
624 cpu_to_le32(metric), cpu_to_le32(preq_id),
626 if (!is_multicast_ether_addr(da))
627 ifmsh->mshstats.fwded_unicast++;
629 ifmsh->mshstats.fwded_mcast++;
630 ifmsh->mshstats.fwded_frames++;
635 static inline struct sta_info *
636 next_hop_deref_protected(struct mesh_path *mpath)
638 return rcu_dereference_protected(mpath->next_hop,
639 lockdep_is_held(&mpath->state_lock));
643 static void hwmp_prep_frame_process(struct ieee80211_sub_if_data *sdata,
644 struct ieee80211_mgmt *mgmt,
645 u8 *prep_elem, u32 metric)
647 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
648 struct mesh_path *mpath;
649 u8 *target_addr, *orig_addr;
650 u8 ttl, hopcount, flags;
651 u8 next_hop[ETH_ALEN];
652 u32 target_sn, orig_sn, lifetime;
654 mhwmp_dbg(sdata, "received PREP from %pM\n",
655 PREP_IE_ORIG_ADDR(prep_elem));
657 orig_addr = PREP_IE_ORIG_ADDR(prep_elem);
658 if (ether_addr_equal(orig_addr, sdata->vif.addr))
659 /* destination, no forwarding required */
662 if (!ifmsh->mshcfg.dot11MeshForwarding)
665 ttl = PREP_IE_TTL(prep_elem);
667 sdata->u.mesh.mshstats.dropped_frames_ttl++;
672 mpath = mesh_path_lookup(orig_addr, sdata);
674 spin_lock_bh(&mpath->state_lock);
677 if (!(mpath->flags & MESH_PATH_ACTIVE)) {
678 spin_unlock_bh(&mpath->state_lock);
681 memcpy(next_hop, next_hop_deref_protected(mpath)->sta.addr, ETH_ALEN);
682 spin_unlock_bh(&mpath->state_lock);
684 flags = PREP_IE_FLAGS(prep_elem);
685 lifetime = PREP_IE_LIFETIME(prep_elem);
686 hopcount = PREP_IE_HOPCOUNT(prep_elem) + 1;
687 target_addr = PREP_IE_TARGET_ADDR(prep_elem);
688 target_sn = PREP_IE_TARGET_SN(prep_elem);
689 orig_sn = PREP_IE_ORIG_SN(prep_elem);
691 mesh_path_sel_frame_tx(MPATH_PREP, flags, orig_addr,
692 cpu_to_le32(orig_sn), 0, target_addr,
693 cpu_to_le32(target_sn), next_hop, hopcount,
694 ttl, cpu_to_le32(lifetime), cpu_to_le32(metric),
698 sdata->u.mesh.mshstats.fwded_unicast++;
699 sdata->u.mesh.mshstats.fwded_frames++;
704 sdata->u.mesh.mshstats.dropped_frames_no_route++;
707 static void hwmp_perr_frame_process(struct ieee80211_sub_if_data *sdata,
708 struct ieee80211_mgmt *mgmt, u8 *perr_elem)
710 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
711 struct mesh_path *mpath;
713 u8 *ta, *target_addr;
718 ttl = PERR_IE_TTL(perr_elem);
720 ifmsh->mshstats.dropped_frames_ttl++;
724 target_addr = PERR_IE_TARGET_ADDR(perr_elem);
725 target_sn = PERR_IE_TARGET_SN(perr_elem);
726 target_rcode = PERR_IE_TARGET_RCODE(perr_elem);
729 mpath = mesh_path_lookup(target_addr, sdata);
731 struct sta_info *sta;
733 spin_lock_bh(&mpath->state_lock);
734 sta = next_hop_deref_protected(mpath);
735 if (mpath->flags & MESH_PATH_ACTIVE &&
736 ether_addr_equal(ta, sta->sta.addr) &&
737 (!(mpath->flags & MESH_PATH_SN_VALID) ||
738 SN_GT(target_sn, mpath->sn))) {
739 mpath->flags &= ~MESH_PATH_ACTIVE;
740 mpath->sn = target_sn;
741 spin_unlock_bh(&mpath->state_lock);
742 if (!ifmsh->mshcfg.dot11MeshForwarding)
744 mesh_path_error_tx(ttl, target_addr, cpu_to_le32(target_sn),
745 cpu_to_le16(target_rcode),
746 broadcast_addr, sdata);
748 spin_unlock_bh(&mpath->state_lock);
754 static void hwmp_rann_frame_process(struct ieee80211_sub_if_data *sdata,
755 struct ieee80211_mgmt *mgmt,
756 struct ieee80211_rann_ie *rann)
758 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
759 struct ieee80211_local *local = sdata->local;
760 struct sta_info *sta;
761 struct mesh_path *mpath;
762 u8 ttl, flags, hopcount;
764 u32 orig_sn, metric, metric_txsta, interval;
767 ttl = rann->rann_ttl;
768 flags = rann->rann_flags;
769 root_is_gate = !!(flags & RANN_FLAG_IS_GATE);
770 orig_addr = rann->rann_addr;
771 orig_sn = le32_to_cpu(rann->rann_seq);
772 interval = le32_to_cpu(rann->rann_interval);
773 hopcount = rann->rann_hopcount;
775 metric = le32_to_cpu(rann->rann_metric);
777 /* Ignore our own RANNs */
778 if (ether_addr_equal(orig_addr, sdata->vif.addr))
782 "received RANN from %pM via neighbour %pM (is_gate=%d)\n",
783 orig_addr, mgmt->sa, root_is_gate);
786 sta = sta_info_get(sdata, mgmt->sa);
792 metric_txsta = airtime_link_metric_get(local, sta);
794 mpath = mesh_path_lookup(orig_addr, sdata);
796 mesh_path_add(orig_addr, sdata);
797 mpath = mesh_path_lookup(orig_addr, sdata);
800 sdata->u.mesh.mshstats.dropped_frames_no_route++;
805 if (!(SN_LT(mpath->sn, orig_sn)) &&
806 !(mpath->sn == orig_sn && metric < mpath->rann_metric)) {
811 if ((!(mpath->flags & (MESH_PATH_ACTIVE | MESH_PATH_RESOLVING)) ||
812 (time_after(jiffies, mpath->last_preq_to_root +
813 root_path_confirmation_jiffies(sdata)) ||
814 time_before(jiffies, mpath->last_preq_to_root))) &&
815 !(mpath->flags & MESH_PATH_FIXED) && (ttl != 0)) {
817 "time to refresh root mpath %pM\n",
819 mesh_queue_preq(mpath, PREQ_Q_F_START | PREQ_Q_F_REFRESH);
820 mpath->last_preq_to_root = jiffies;
824 mpath->rann_metric = metric + metric_txsta;
825 mpath->is_root = true;
826 /* Recording RANNs sender address to send individually
827 * addressed PREQs destined for root mesh STA */
828 memcpy(mpath->rann_snd_addr, mgmt->sa, ETH_ALEN);
831 mesh_path_add_gate(mpath);
834 ifmsh->mshstats.dropped_frames_ttl++;
840 if (ifmsh->mshcfg.dot11MeshForwarding) {
841 mesh_path_sel_frame_tx(MPATH_RANN, flags, orig_addr,
842 cpu_to_le32(orig_sn),
843 0, NULL, 0, broadcast_addr,
844 hopcount, ttl, cpu_to_le32(interval),
845 cpu_to_le32(metric + metric_txsta),
853 void mesh_rx_path_sel_frame(struct ieee80211_sub_if_data *sdata,
854 struct ieee80211_mgmt *mgmt,
857 struct ieee802_11_elems elems;
860 struct sta_info *sta;
862 /* need action_code */
863 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
867 sta = sta_info_get(sdata, mgmt->sa);
868 if (!sta || sta->plink_state != NL80211_PLINK_ESTAB) {
874 baselen = (u8 *) mgmt->u.action.u.mesh_action.variable - (u8 *) mgmt;
875 ieee802_11_parse_elems(mgmt->u.action.u.mesh_action.variable,
876 len - baselen, &elems);
879 if (elems.preq_len != 37)
880 /* Right now we support just 1 destination and no AE */
882 last_hop_metric = hwmp_route_info_get(sdata, mgmt, elems.preq,
885 hwmp_preq_frame_process(sdata, mgmt, elems.preq,
889 if (elems.prep_len != 31)
890 /* Right now we support no AE */
892 last_hop_metric = hwmp_route_info_get(sdata, mgmt, elems.prep,
895 hwmp_prep_frame_process(sdata, mgmt, elems.prep,
899 if (elems.perr_len != 15)
900 /* Right now we support only one destination per PERR */
902 hwmp_perr_frame_process(sdata, mgmt, elems.perr);
905 hwmp_rann_frame_process(sdata, mgmt, elems.rann);
909 * mesh_queue_preq - queue a PREQ to a given destination
911 * @mpath: mesh path to discover
912 * @flags: special attributes of the PREQ to be sent
914 * Locking: the function must be called from within a rcu read lock block.
917 static void mesh_queue_preq(struct mesh_path *mpath, u8 flags)
919 struct ieee80211_sub_if_data *sdata = mpath->sdata;
920 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
921 struct mesh_preq_queue *preq_node;
923 preq_node = kmalloc(sizeof(struct mesh_preq_queue), GFP_ATOMIC);
925 mhwmp_dbg(sdata, "could not allocate PREQ node\n");
929 spin_lock_bh(&ifmsh->mesh_preq_queue_lock);
930 if (ifmsh->preq_queue_len == MAX_PREQ_QUEUE_LEN) {
931 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
933 if (printk_ratelimit())
934 mhwmp_dbg(sdata, "PREQ node queue full\n");
938 spin_lock(&mpath->state_lock);
939 if (mpath->flags & MESH_PATH_REQ_QUEUED) {
940 spin_unlock(&mpath->state_lock);
941 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
946 memcpy(preq_node->dst, mpath->dst, ETH_ALEN);
947 preq_node->flags = flags;
949 mpath->flags |= MESH_PATH_REQ_QUEUED;
950 spin_unlock(&mpath->state_lock);
952 list_add_tail(&preq_node->list, &ifmsh->preq_queue.list);
953 ++ifmsh->preq_queue_len;
954 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
956 if (time_after(jiffies, ifmsh->last_preq + min_preq_int_jiff(sdata)))
957 ieee80211_queue_work(&sdata->local->hw, &sdata->work);
959 else if (time_before(jiffies, ifmsh->last_preq)) {
960 /* avoid long wait if did not send preqs for a long time
961 * and jiffies wrapped around
963 ifmsh->last_preq = jiffies - min_preq_int_jiff(sdata) - 1;
964 ieee80211_queue_work(&sdata->local->hw, &sdata->work);
966 mod_timer(&ifmsh->mesh_path_timer, ifmsh->last_preq +
967 min_preq_int_jiff(sdata));
971 * mesh_path_start_discovery - launch a path discovery from the PREQ queue
973 * @sdata: local mesh subif
975 void mesh_path_start_discovery(struct ieee80211_sub_if_data *sdata)
977 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
978 struct mesh_preq_queue *preq_node;
979 struct mesh_path *mpath;
980 u8 ttl, target_flags;
984 spin_lock_bh(&ifmsh->mesh_preq_queue_lock);
985 if (!ifmsh->preq_queue_len ||
986 time_before(jiffies, ifmsh->last_preq +
987 min_preq_int_jiff(sdata))) {
988 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
992 preq_node = list_first_entry(&ifmsh->preq_queue.list,
993 struct mesh_preq_queue, list);
994 list_del(&preq_node->list);
995 --ifmsh->preq_queue_len;
996 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
999 mpath = mesh_path_lookup(preq_node->dst, sdata);
1003 spin_lock_bh(&mpath->state_lock);
1004 mpath->flags &= ~MESH_PATH_REQ_QUEUED;
1005 if (preq_node->flags & PREQ_Q_F_START) {
1006 if (mpath->flags & MESH_PATH_RESOLVING) {
1007 spin_unlock_bh(&mpath->state_lock);
1010 mpath->flags &= ~MESH_PATH_RESOLVED;
1011 mpath->flags |= MESH_PATH_RESOLVING;
1012 mpath->discovery_retries = 0;
1013 mpath->discovery_timeout = disc_timeout_jiff(sdata);
1015 } else if (!(mpath->flags & MESH_PATH_RESOLVING) ||
1016 mpath->flags & MESH_PATH_RESOLVED) {
1017 mpath->flags &= ~MESH_PATH_RESOLVING;
1018 spin_unlock_bh(&mpath->state_lock);
1022 ifmsh->last_preq = jiffies;
1024 if (time_after(jiffies, ifmsh->last_sn_update +
1025 net_traversal_jiffies(sdata)) ||
1026 time_before(jiffies, ifmsh->last_sn_update)) {
1028 sdata->u.mesh.last_sn_update = jiffies;
1030 lifetime = default_lifetime(sdata);
1031 ttl = sdata->u.mesh.mshcfg.element_ttl;
1033 sdata->u.mesh.mshstats.dropped_frames_ttl++;
1034 spin_unlock_bh(&mpath->state_lock);
1038 if (preq_node->flags & PREQ_Q_F_REFRESH)
1039 target_flags = MP_F_DO;
1041 target_flags = MP_F_RF;
1043 spin_unlock_bh(&mpath->state_lock);
1044 da = (mpath->is_root) ? mpath->rann_snd_addr : broadcast_addr;
1045 mesh_path_sel_frame_tx(MPATH_PREQ, 0, sdata->vif.addr,
1046 cpu_to_le32(ifmsh->sn), target_flags, mpath->dst,
1047 cpu_to_le32(mpath->sn), da, 0,
1048 ttl, cpu_to_le32(lifetime), 0,
1049 cpu_to_le32(ifmsh->preq_id++), sdata);
1050 mod_timer(&mpath->timer, jiffies + mpath->discovery_timeout);
1058 * mesh_nexthop_resolve - lookup next hop; conditionally start path discovery
1060 * @skb: 802.11 frame to be sent
1061 * @sdata: network subif the frame will be sent through
1063 * Lookup next hop for given skb and start path discovery if no
1064 * forwarding information is found.
1066 * Returns: 0 if the next hop was found and -ENOENT if the frame was queued.
1067 * skb is freeed here if no mpath could be allocated.
1069 int mesh_nexthop_resolve(struct sk_buff *skb,
1070 struct ieee80211_sub_if_data *sdata)
1072 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1073 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1074 struct mesh_path *mpath;
1075 struct sk_buff *skb_to_free = NULL;
1076 u8 *target_addr = hdr->addr3;
1080 err = mesh_nexthop_lookup(skb, sdata);
1084 /* no nexthop found, start resolving */
1085 mpath = mesh_path_lookup(target_addr, sdata);
1087 mesh_path_add(target_addr, sdata);
1088 mpath = mesh_path_lookup(target_addr, sdata);
1090 mesh_path_discard_frame(skb, sdata);
1096 if (!(mpath->flags & MESH_PATH_RESOLVING))
1097 mesh_queue_preq(mpath, PREQ_Q_F_START);
1099 if (skb_queue_len(&mpath->frame_queue) >= MESH_FRAME_QUEUE_LEN)
1100 skb_to_free = skb_dequeue(&mpath->frame_queue);
1102 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1103 ieee80211_set_qos_hdr(sdata, skb);
1104 skb_queue_tail(&mpath->frame_queue, skb);
1107 mesh_path_discard_frame(skb_to_free, sdata);
1114 * mesh_nexthop_lookup - put the appropriate next hop on a mesh frame. Calling
1115 * this function is considered "using" the associated mpath, so preempt a path
1116 * refresh if this mpath expires soon.
1118 * @skb: 802.11 frame to be sent
1119 * @sdata: network subif the frame will be sent through
1121 * Returns: 0 if the next hop was found. Nonzero otherwise.
1123 int mesh_nexthop_lookup(struct sk_buff *skb,
1124 struct ieee80211_sub_if_data *sdata)
1126 struct mesh_path *mpath;
1127 struct sta_info *next_hop;
1128 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1129 u8 *target_addr = hdr->addr3;
1133 mpath = mesh_path_lookup(target_addr, sdata);
1135 if (!mpath || !(mpath->flags & MESH_PATH_ACTIVE))
1138 if (time_after(jiffies,
1140 msecs_to_jiffies(sdata->u.mesh.mshcfg.path_refresh_time)) &&
1141 ether_addr_equal(sdata->vif.addr, hdr->addr4) &&
1142 !(mpath->flags & MESH_PATH_RESOLVING) &&
1143 !(mpath->flags & MESH_PATH_FIXED))
1144 mesh_queue_preq(mpath, PREQ_Q_F_START | PREQ_Q_F_REFRESH);
1146 next_hop = rcu_dereference(mpath->next_hop);
1148 memcpy(hdr->addr1, next_hop->sta.addr, ETH_ALEN);
1149 memcpy(hdr->addr2, sdata->vif.addr, ETH_ALEN);
1158 void mesh_path_timer(unsigned long data)
1160 struct mesh_path *mpath = (void *) data;
1161 struct ieee80211_sub_if_data *sdata = mpath->sdata;
1164 if (sdata->local->quiescing)
1167 spin_lock_bh(&mpath->state_lock);
1168 if (mpath->flags & MESH_PATH_RESOLVED ||
1169 (!(mpath->flags & MESH_PATH_RESOLVING))) {
1170 mpath->flags &= ~(MESH_PATH_RESOLVING | MESH_PATH_RESOLVED);
1171 spin_unlock_bh(&mpath->state_lock);
1172 } else if (mpath->discovery_retries < max_preq_retries(sdata)) {
1173 ++mpath->discovery_retries;
1174 mpath->discovery_timeout *= 2;
1175 mpath->flags &= ~MESH_PATH_REQ_QUEUED;
1176 spin_unlock_bh(&mpath->state_lock);
1177 mesh_queue_preq(mpath, 0);
1180 mpath->exp_time = jiffies;
1181 spin_unlock_bh(&mpath->state_lock);
1182 if (!mpath->is_gate && mesh_gate_num(sdata) > 0) {
1183 ret = mesh_path_send_to_gates(mpath);
1185 mhwmp_dbg(sdata, "no gate was reachable\n");
1187 mesh_path_flush_pending(mpath);
1192 mesh_path_tx_root_frame(struct ieee80211_sub_if_data *sdata)
1194 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1195 u32 interval = ifmsh->mshcfg.dot11MeshHWMPRannInterval;
1196 u8 flags, target_flags = 0;
1198 flags = (ifmsh->mshcfg.dot11MeshGateAnnouncementProtocol)
1199 ? RANN_FLAG_IS_GATE : 0;
1201 switch (ifmsh->mshcfg.dot11MeshHWMPRootMode) {
1202 case IEEE80211_PROACTIVE_RANN:
1203 mesh_path_sel_frame_tx(MPATH_RANN, flags, sdata->vif.addr,
1204 cpu_to_le32(++ifmsh->sn),
1205 0, NULL, 0, broadcast_addr,
1206 0, ifmsh->mshcfg.element_ttl,
1207 cpu_to_le32(interval), 0, 0, sdata);
1209 case IEEE80211_PROACTIVE_PREQ_WITH_PREP:
1210 flags |= IEEE80211_PREQ_PROACTIVE_PREP_FLAG;
1211 case IEEE80211_PROACTIVE_PREQ_NO_PREP:
1212 interval = ifmsh->mshcfg.dot11MeshHWMPactivePathToRootTimeout;
1213 target_flags |= IEEE80211_PREQ_TO_FLAG |
1214 IEEE80211_PREQ_USN_FLAG;
1215 mesh_path_sel_frame_tx(MPATH_PREQ, flags, sdata->vif.addr,
1216 cpu_to_le32(++ifmsh->sn), target_flags,
1217 (u8 *) broadcast_addr, 0, broadcast_addr,
1218 0, ifmsh->mshcfg.element_ttl,
1219 cpu_to_le32(interval),
1220 0, cpu_to_le32(ifmsh->preq_id++), sdata);
1223 mhwmp_dbg(sdata, "Proactive mechanism not supported\n");