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 /* Destination only */
24 /* Reply and forward */
26 /* Unknown Sequence Number */
28 /* Reason code Present */
29 #define MP_F_RCODE 0x02
31 static void mesh_queue_preq(struct mesh_path *, u8);
33 static inline u32 u32_field_get(const u8 *preq_elem, int offset, bool ae)
37 return get_unaligned_le32(preq_elem + offset);
40 static inline u16 u16_field_get(const u8 *preq_elem, int offset, bool ae)
44 return get_unaligned_le16(preq_elem + offset);
47 /* HWMP IE processing macros */
49 #define AE_F_SET(x) (*x & AE_F)
50 #define PREQ_IE_FLAGS(x) (*(x))
51 #define PREQ_IE_HOPCOUNT(x) (*(x + 1))
52 #define PREQ_IE_TTL(x) (*(x + 2))
53 #define PREQ_IE_PREQ_ID(x) u32_field_get(x, 3, 0)
54 #define PREQ_IE_ORIG_ADDR(x) (x + 7)
55 #define PREQ_IE_ORIG_SN(x) u32_field_get(x, 13, 0)
56 #define PREQ_IE_LIFETIME(x) u32_field_get(x, 17, AE_F_SET(x))
57 #define PREQ_IE_METRIC(x) u32_field_get(x, 21, AE_F_SET(x))
58 #define PREQ_IE_TARGET_F(x) (*(AE_F_SET(x) ? x + 32 : x + 26))
59 #define PREQ_IE_TARGET_ADDR(x) (AE_F_SET(x) ? x + 33 : x + 27)
60 #define PREQ_IE_TARGET_SN(x) u32_field_get(x, 33, AE_F_SET(x))
63 #define PREP_IE_FLAGS(x) PREQ_IE_FLAGS(x)
64 #define PREP_IE_HOPCOUNT(x) PREQ_IE_HOPCOUNT(x)
65 #define PREP_IE_TTL(x) PREQ_IE_TTL(x)
66 #define PREP_IE_ORIG_ADDR(x) (AE_F_SET(x) ? x + 27 : x + 21)
67 #define PREP_IE_ORIG_SN(x) u32_field_get(x, 27, AE_F_SET(x))
68 #define PREP_IE_LIFETIME(x) u32_field_get(x, 13, AE_F_SET(x))
69 #define PREP_IE_METRIC(x) u32_field_get(x, 17, AE_F_SET(x))
70 #define PREP_IE_TARGET_ADDR(x) (x + 3)
71 #define PREP_IE_TARGET_SN(x) u32_field_get(x, 9, 0)
73 #define PERR_IE_TTL(x) (*(x))
74 #define PERR_IE_TARGET_FLAGS(x) (*(x + 2))
75 #define PERR_IE_TARGET_ADDR(x) (x + 3)
76 #define PERR_IE_TARGET_SN(x) u32_field_get(x, 9, 0)
77 #define PERR_IE_TARGET_RCODE(x) u16_field_get(x, 13, 0)
79 #define MSEC_TO_TU(x) (x*1000/1024)
80 #define SN_GT(x, y) ((s32)(y - x) < 0)
81 #define SN_LT(x, y) ((s32)(x - y) < 0)
83 #define net_traversal_jiffies(s) \
84 msecs_to_jiffies(s->u.mesh.mshcfg.dot11MeshHWMPnetDiameterTraversalTime)
85 #define default_lifetime(s) \
86 MSEC_TO_TU(s->u.mesh.mshcfg.dot11MeshHWMPactivePathTimeout)
87 #define min_preq_int_jiff(s) \
88 (msecs_to_jiffies(s->u.mesh.mshcfg.dot11MeshHWMPpreqMinInterval))
89 #define max_preq_retries(s) (s->u.mesh.mshcfg.dot11MeshHWMPmaxPREQretries)
90 #define disc_timeout_jiff(s) \
91 msecs_to_jiffies(sdata->u.mesh.mshcfg.min_discovery_timeout)
92 #define root_path_confirmation_jiffies(s) \
93 msecs_to_jiffies(sdata->u.mesh.mshcfg.dot11MeshHWMPconfirmationInterval)
95 enum mpath_frame_type {
102 static const u8 broadcast_addr[ETH_ALEN] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
104 static int mesh_path_sel_frame_tx(enum mpath_frame_type action, u8 flags,
105 const u8 *orig_addr, u32 orig_sn,
106 u8 target_flags, const u8 *target,
107 u32 target_sn, const u8 *da,
108 u8 hop_count, u8 ttl,
109 u32 lifetime, u32 metric, u32 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", orig_addr);
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;
165 if (action == MPATH_PREP) {
166 memcpy(pos, target, ETH_ALEN);
168 put_unaligned_le32(target_sn, pos);
171 if (action == MPATH_PREQ) {
172 put_unaligned_le32(preq_id, pos);
175 memcpy(pos, orig_addr, ETH_ALEN);
177 put_unaligned_le32(orig_sn, pos);
180 put_unaligned_le32(lifetime, pos); /* interval for RANN */
182 put_unaligned_le32(metric, pos);
184 if (action == MPATH_PREQ) {
185 *pos++ = 1; /* destination count */
186 *pos++ = target_flags;
187 memcpy(pos, target, ETH_ALEN);
189 put_unaligned_le32(target_sn, pos);
191 } else if (action == MPATH_PREP) {
192 memcpy(pos, orig_addr, ETH_ALEN);
194 put_unaligned_le32(orig_sn, pos);
198 ieee80211_tx_skb(sdata, skb);
203 /* Headroom is not adjusted. Caller should ensure that skb has sufficient
204 * headroom in case the frame is encrypted. */
205 static void prepare_frame_for_deferred_tx(struct ieee80211_sub_if_data *sdata,
208 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
209 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
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 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
221 ieee80211_set_qos_hdr(sdata, skb);
222 ieee80211_mps_set_frame_flags(sdata, NULL, hdr);
226 * mesh_path_error_tx - Sends a PERR mesh management frame
228 * @ttl: allowed remaining hops
229 * @target: broken destination
230 * @target_sn: SN of the broken destination
231 * @target_rcode: reason code for this PERR
232 * @ra: node this frame is addressed to
233 * @sdata: local mesh subif
235 * Note: This function may be called with driver locks taken that the driver
236 * also acquires in the TX path. To avoid a deadlock we don't transmit the
237 * frame directly but add it to the pending queue instead.
239 int mesh_path_error_tx(struct ieee80211_sub_if_data *sdata,
240 u8 ttl, const u8 *target, u32 target_sn,
241 u16 target_rcode, const u8 *ra)
243 struct ieee80211_local *local = sdata->local;
245 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
246 struct ieee80211_mgmt *mgmt;
248 int hdr_len = offsetof(struct ieee80211_mgmt, u.action.u.mesh_action) +
249 sizeof(mgmt->u.action.u.mesh_action);
251 if (time_before(jiffies, ifmsh->next_perr))
254 skb = dev_alloc_skb(local->tx_headroom +
255 sdata->encrypt_headroom +
256 IEEE80211_ENCRYPT_TAILROOM +
258 2 + 15 /* PERR IE */);
261 skb_reserve(skb, local->tx_headroom + sdata->encrypt_headroom);
262 mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len);
263 memset(mgmt, 0, hdr_len);
264 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
265 IEEE80211_STYPE_ACTION);
267 memcpy(mgmt->da, ra, ETH_ALEN);
268 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
270 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
271 mgmt->u.action.category = WLAN_CATEGORY_MESH_ACTION;
272 mgmt->u.action.u.mesh_action.action_code =
273 WLAN_MESH_ACTION_HWMP_PATH_SELECTION;
275 pos = skb_put(skb, 2 + ie_len);
276 *pos++ = WLAN_EID_PERR;
280 /* number of destinations */
283 * flags bit, bit 1 is unset if we know the sequence number and
284 * bit 2 is set if we have a reason code
292 memcpy(pos, target, ETH_ALEN);
294 put_unaligned_le32(target_sn, pos);
296 put_unaligned_le16(target_rcode, pos);
298 /* see note in function header */
299 prepare_frame_for_deferred_tx(sdata, skb);
300 ifmsh->next_perr = TU_TO_EXP_TIME(
301 ifmsh->mshcfg.dot11MeshHWMPperrMinInterval);
302 ieee80211_add_pending_skb(local, skb);
306 void ieee80211s_update_metric(struct ieee80211_local *local,
307 struct sta_info *sta, struct sk_buff *skb)
309 struct ieee80211_tx_info *txinfo = IEEE80211_SKB_CB(skb);
310 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
313 if (!ieee80211_is_data(hdr->frame_control))
316 failed = !(txinfo->flags & IEEE80211_TX_STAT_ACK);
318 /* moving average, scaled to 100 */
319 sta->fail_avg = ((80 * sta->fail_avg + 5) / 100 + 20 * failed);
320 if (sta->fail_avg > 95)
321 mesh_plink_broken(sta);
324 static u32 airtime_link_metric_get(struct ieee80211_local *local,
325 struct sta_info *sta)
327 struct rate_info rinfo;
328 /* This should be adjusted for each device */
329 int device_constant = 1 << ARITH_SHIFT;
330 int test_frame_len = TEST_FRAME_LEN << ARITH_SHIFT;
331 int s_unit = 1 << ARITH_SHIFT;
333 u32 tx_time, estimated_retx;
336 if (sta->fail_avg >= 100)
339 sta_set_rate_info_tx(sta, &sta->last_tx_rate, &rinfo);
340 rate = cfg80211_calculate_bitrate(&rinfo);
344 err = (sta->fail_avg << ARITH_SHIFT) / 100;
346 /* bitrate is in units of 100 Kbps, while we need rate in units of
347 * 1Mbps. This will be corrected on tx_time computation.
349 tx_time = (device_constant + 10 * test_frame_len / rate);
350 estimated_retx = ((1 << (2 * ARITH_SHIFT)) / (s_unit - err));
351 result = (tx_time * estimated_retx) >> (2 * ARITH_SHIFT) ;
356 * hwmp_route_info_get - Update routing info to originator and transmitter
358 * @sdata: local mesh subif
359 * @mgmt: mesh management frame
360 * @hwmp_ie: hwmp information element (PREP or PREQ)
361 * @action: type of hwmp ie
363 * This function updates the path routing information to the originator and the
364 * transmitter of a HWMP PREQ or PREP frame.
366 * Returns: metric to frame originator or 0 if the frame should not be further
369 * Notes: this function is the only place (besides user-provided info) where
370 * path routing information is updated.
372 static u32 hwmp_route_info_get(struct ieee80211_sub_if_data *sdata,
373 struct ieee80211_mgmt *mgmt,
374 const u8 *hwmp_ie, enum mpath_frame_type action)
376 struct ieee80211_local *local = sdata->local;
377 struct mesh_path *mpath;
378 struct sta_info *sta;
380 const u8 *orig_addr, *ta;
381 u32 orig_sn, orig_metric;
382 unsigned long orig_lifetime, exp_time;
383 u32 last_hop_metric, new_metric;
387 sta = sta_info_get(sdata, mgmt->sa);
393 last_hop_metric = airtime_link_metric_get(local, sta);
394 /* Update and check originator routing info */
399 orig_addr = PREQ_IE_ORIG_ADDR(hwmp_ie);
400 orig_sn = PREQ_IE_ORIG_SN(hwmp_ie);
401 orig_lifetime = PREQ_IE_LIFETIME(hwmp_ie);
402 orig_metric = PREQ_IE_METRIC(hwmp_ie);
405 /* Originator here refers to the MP that was the target in the
406 * Path Request. We divert from the nomenclature in the draft
407 * so that we can easily use a single function to gather path
408 * information from both PREQ and PREP frames.
410 orig_addr = PREP_IE_TARGET_ADDR(hwmp_ie);
411 orig_sn = PREP_IE_TARGET_SN(hwmp_ie);
412 orig_lifetime = PREP_IE_LIFETIME(hwmp_ie);
413 orig_metric = PREP_IE_METRIC(hwmp_ie);
419 new_metric = orig_metric + last_hop_metric;
420 if (new_metric < orig_metric)
421 new_metric = MAX_METRIC;
422 exp_time = TU_TO_EXP_TIME(orig_lifetime);
424 if (ether_addr_equal(orig_addr, sdata->vif.addr)) {
425 /* This MP is the originator, we are not interested in this
426 * frame, except for updating transmitter's path info.
431 mpath = mesh_path_lookup(sdata, orig_addr);
433 spin_lock_bh(&mpath->state_lock);
434 if (mpath->flags & MESH_PATH_FIXED)
436 else if ((mpath->flags & MESH_PATH_ACTIVE) &&
437 (mpath->flags & MESH_PATH_SN_VALID)) {
438 if (SN_GT(mpath->sn, orig_sn) ||
439 (mpath->sn == orig_sn &&
440 new_metric >= mpath->metric)) {
446 mpath = mesh_path_add(sdata, orig_addr);
451 spin_lock_bh(&mpath->state_lock);
455 mesh_path_assign_nexthop(mpath, sta);
456 mpath->flags |= MESH_PATH_SN_VALID;
457 mpath->metric = new_metric;
459 mpath->exp_time = time_after(mpath->exp_time, exp_time)
460 ? mpath->exp_time : exp_time;
461 mesh_path_activate(mpath);
462 spin_unlock_bh(&mpath->state_lock);
463 mesh_path_tx_pending(mpath);
464 /* draft says preq_id should be saved to, but there does
465 * not seem to be any use for it, skipping by now
468 spin_unlock_bh(&mpath->state_lock);
471 /* Update and check transmitter routing info */
473 if (ether_addr_equal(orig_addr, ta))
478 mpath = mesh_path_lookup(sdata, ta);
480 spin_lock_bh(&mpath->state_lock);
481 if ((mpath->flags & MESH_PATH_FIXED) ||
482 ((mpath->flags & MESH_PATH_ACTIVE) &&
483 (last_hop_metric > mpath->metric)))
486 mpath = mesh_path_add(sdata, ta);
491 spin_lock_bh(&mpath->state_lock);
495 mesh_path_assign_nexthop(mpath, sta);
496 mpath->metric = last_hop_metric;
497 mpath->exp_time = time_after(mpath->exp_time, exp_time)
498 ? mpath->exp_time : exp_time;
499 mesh_path_activate(mpath);
500 spin_unlock_bh(&mpath->state_lock);
501 mesh_path_tx_pending(mpath);
503 spin_unlock_bh(&mpath->state_lock);
508 return process ? new_metric : 0;
511 static void hwmp_preq_frame_process(struct ieee80211_sub_if_data *sdata,
512 struct ieee80211_mgmt *mgmt,
513 const u8 *preq_elem, u32 orig_metric)
515 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
516 struct mesh_path *mpath = NULL;
517 const u8 *target_addr, *orig_addr;
519 u8 target_flags, ttl, flags;
520 u32 orig_sn, target_sn, lifetime, target_metric;
525 /* Update target SN, if present */
526 target_addr = PREQ_IE_TARGET_ADDR(preq_elem);
527 orig_addr = PREQ_IE_ORIG_ADDR(preq_elem);
528 target_sn = PREQ_IE_TARGET_SN(preq_elem);
529 orig_sn = PREQ_IE_ORIG_SN(preq_elem);
530 target_flags = PREQ_IE_TARGET_F(preq_elem);
531 /* Proactive PREQ gate announcements */
532 flags = PREQ_IE_FLAGS(preq_elem);
533 root_is_gate = !!(flags & RANN_FLAG_IS_GATE);
535 mhwmp_dbg(sdata, "received PREQ from %pM\n", orig_addr);
537 if (ether_addr_equal(target_addr, sdata->vif.addr)) {
538 mhwmp_dbg(sdata, "PREQ is for us\n");
542 if (time_after(jiffies, ifmsh->last_sn_update +
543 net_traversal_jiffies(sdata)) ||
544 time_before(jiffies, ifmsh->last_sn_update)) {
546 ifmsh->last_sn_update = jiffies;
548 target_sn = ifmsh->sn;
549 } else if (is_broadcast_ether_addr(target_addr) &&
550 (target_flags & IEEE80211_PREQ_TO_FLAG)) {
552 mpath = mesh_path_lookup(sdata, orig_addr);
554 if (flags & IEEE80211_PREQ_PROACTIVE_PREP_FLAG) {
556 target_addr = sdata->vif.addr;
557 target_sn = ++ifmsh->sn;
559 ifmsh->last_sn_update = jiffies;
562 mesh_path_add_gate(mpath);
567 mpath = mesh_path_lookup(sdata, target_addr);
569 if ((!(mpath->flags & MESH_PATH_SN_VALID)) ||
570 SN_LT(mpath->sn, target_sn)) {
571 mpath->sn = target_sn;
572 mpath->flags |= MESH_PATH_SN_VALID;
573 } else if ((!(target_flags & MP_F_DO)) &&
574 (mpath->flags & MESH_PATH_ACTIVE)) {
576 target_metric = mpath->metric;
577 target_sn = mpath->sn;
578 if (target_flags & MP_F_RF)
579 target_flags |= MP_F_DO;
588 lifetime = PREQ_IE_LIFETIME(preq_elem);
589 ttl = ifmsh->mshcfg.element_ttl;
591 mhwmp_dbg(sdata, "replying to the PREQ\n");
592 mesh_path_sel_frame_tx(MPATH_PREP, 0, orig_addr,
593 orig_sn, 0, target_addr,
594 target_sn, mgmt->sa, 0, ttl,
595 lifetime, target_metric, 0,
598 ifmsh->mshstats.dropped_frames_ttl++;
602 if (forward && ifmsh->mshcfg.dot11MeshForwarding) {
606 ttl = PREQ_IE_TTL(preq_elem);
607 lifetime = PREQ_IE_LIFETIME(preq_elem);
609 ifmsh->mshstats.dropped_frames_ttl++;
612 mhwmp_dbg(sdata, "forwarding the PREQ from %pM\n", orig_addr);
614 preq_id = PREQ_IE_PREQ_ID(preq_elem);
615 hopcount = PREQ_IE_HOPCOUNT(preq_elem) + 1;
616 da = (mpath && mpath->is_root) ?
617 mpath->rann_snd_addr : broadcast_addr;
619 if (flags & IEEE80211_PREQ_PROACTIVE_PREP_FLAG) {
620 target_addr = PREQ_IE_TARGET_ADDR(preq_elem);
621 target_sn = PREQ_IE_TARGET_SN(preq_elem);
624 mesh_path_sel_frame_tx(MPATH_PREQ, flags, orig_addr,
625 orig_sn, target_flags, target_addr,
626 target_sn, da, hopcount, ttl, lifetime,
627 orig_metric, preq_id, sdata);
628 if (!is_multicast_ether_addr(da))
629 ifmsh->mshstats.fwded_unicast++;
631 ifmsh->mshstats.fwded_mcast++;
632 ifmsh->mshstats.fwded_frames++;
637 static inline struct sta_info *
638 next_hop_deref_protected(struct mesh_path *mpath)
640 return rcu_dereference_protected(mpath->next_hop,
641 lockdep_is_held(&mpath->state_lock));
645 static void hwmp_prep_frame_process(struct ieee80211_sub_if_data *sdata,
646 struct ieee80211_mgmt *mgmt,
647 const u8 *prep_elem, u32 metric)
649 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
650 struct mesh_path *mpath;
651 const u8 *target_addr, *orig_addr;
652 u8 ttl, hopcount, flags;
653 u8 next_hop[ETH_ALEN];
654 u32 target_sn, orig_sn, lifetime;
656 mhwmp_dbg(sdata, "received PREP from %pM\n",
657 PREP_IE_TARGET_ADDR(prep_elem));
659 orig_addr = PREP_IE_ORIG_ADDR(prep_elem);
660 if (ether_addr_equal(orig_addr, sdata->vif.addr))
661 /* destination, no forwarding required */
664 if (!ifmsh->mshcfg.dot11MeshForwarding)
667 ttl = PREP_IE_TTL(prep_elem);
669 sdata->u.mesh.mshstats.dropped_frames_ttl++;
674 mpath = mesh_path_lookup(sdata, orig_addr);
676 spin_lock_bh(&mpath->state_lock);
679 if (!(mpath->flags & MESH_PATH_ACTIVE)) {
680 spin_unlock_bh(&mpath->state_lock);
683 memcpy(next_hop, next_hop_deref_protected(mpath)->sta.addr, ETH_ALEN);
684 spin_unlock_bh(&mpath->state_lock);
686 flags = PREP_IE_FLAGS(prep_elem);
687 lifetime = PREP_IE_LIFETIME(prep_elem);
688 hopcount = PREP_IE_HOPCOUNT(prep_elem) + 1;
689 target_addr = PREP_IE_TARGET_ADDR(prep_elem);
690 target_sn = PREP_IE_TARGET_SN(prep_elem);
691 orig_sn = PREP_IE_ORIG_SN(prep_elem);
693 mesh_path_sel_frame_tx(MPATH_PREP, flags, orig_addr, orig_sn, 0,
694 target_addr, target_sn, next_hop, hopcount,
695 ttl, lifetime, metric, 0, sdata);
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,
711 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
712 struct mesh_path *mpath;
714 const u8 *ta, *target_addr;
719 ttl = PERR_IE_TTL(perr_elem);
721 ifmsh->mshstats.dropped_frames_ttl++;
725 target_addr = PERR_IE_TARGET_ADDR(perr_elem);
726 target_sn = PERR_IE_TARGET_SN(perr_elem);
727 target_rcode = PERR_IE_TARGET_RCODE(perr_elem);
730 mpath = mesh_path_lookup(sdata, target_addr);
732 struct sta_info *sta;
734 spin_lock_bh(&mpath->state_lock);
735 sta = next_hop_deref_protected(mpath);
736 if (mpath->flags & MESH_PATH_ACTIVE &&
737 ether_addr_equal(ta, sta->sta.addr) &&
738 (!(mpath->flags & MESH_PATH_SN_VALID) ||
739 SN_GT(target_sn, mpath->sn))) {
740 mpath->flags &= ~MESH_PATH_ACTIVE;
741 mpath->sn = target_sn;
742 spin_unlock_bh(&mpath->state_lock);
743 if (!ifmsh->mshcfg.dot11MeshForwarding)
745 mesh_path_error_tx(sdata, ttl, target_addr,
746 target_sn, target_rcode,
749 spin_unlock_bh(&mpath->state_lock);
755 static void hwmp_rann_frame_process(struct ieee80211_sub_if_data *sdata,
756 struct ieee80211_mgmt *mgmt,
757 const struct ieee80211_rann_ie *rann)
759 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
760 struct ieee80211_local *local = sdata->local;
761 struct sta_info *sta;
762 struct mesh_path *mpath;
763 u8 ttl, flags, hopcount;
765 u32 orig_sn, metric, metric_txsta, interval;
768 ttl = rann->rann_ttl;
769 flags = rann->rann_flags;
770 root_is_gate = !!(flags & RANN_FLAG_IS_GATE);
771 orig_addr = rann->rann_addr;
772 orig_sn = le32_to_cpu(rann->rann_seq);
773 interval = le32_to_cpu(rann->rann_interval);
774 hopcount = rann->rann_hopcount;
776 metric = le32_to_cpu(rann->rann_metric);
778 /* Ignore our own RANNs */
779 if (ether_addr_equal(orig_addr, sdata->vif.addr))
783 "received RANN from %pM via neighbour %pM (is_gate=%d)\n",
784 orig_addr, mgmt->sa, root_is_gate);
787 sta = sta_info_get(sdata, mgmt->sa);
793 metric_txsta = airtime_link_metric_get(local, sta);
795 mpath = mesh_path_lookup(sdata, orig_addr);
797 mpath = mesh_path_add(sdata, orig_addr);
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 orig_sn, 0, NULL, 0, broadcast_addr,
843 hopcount, ttl, interval,
844 metric + metric_txsta, 0, sdata);
851 void mesh_rx_path_sel_frame(struct ieee80211_sub_if_data *sdata,
852 struct ieee80211_mgmt *mgmt, size_t len)
854 struct ieee802_11_elems elems;
857 struct sta_info *sta;
859 /* need action_code */
860 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
864 sta = sta_info_get(sdata, mgmt->sa);
865 if (!sta || sta->plink_state != NL80211_PLINK_ESTAB) {
871 baselen = (u8 *) mgmt->u.action.u.mesh_action.variable - (u8 *) mgmt;
872 ieee802_11_parse_elems(mgmt->u.action.u.mesh_action.variable,
873 len - baselen, false, &elems);
876 if (elems.preq_len != 37)
877 /* Right now we support just 1 destination and no AE */
879 path_metric = hwmp_route_info_get(sdata, mgmt, elems.preq,
882 hwmp_preq_frame_process(sdata, mgmt, elems.preq,
886 if (elems.prep_len != 31)
887 /* Right now we support no AE */
889 path_metric = hwmp_route_info_get(sdata, mgmt, elems.prep,
892 hwmp_prep_frame_process(sdata, mgmt, elems.prep,
896 if (elems.perr_len != 15)
897 /* Right now we support only one destination per PERR */
899 hwmp_perr_frame_process(sdata, mgmt, elems.perr);
902 hwmp_rann_frame_process(sdata, mgmt, elems.rann);
906 * mesh_queue_preq - queue a PREQ to a given destination
908 * @mpath: mesh path to discover
909 * @flags: special attributes of the PREQ to be sent
911 * Locking: the function must be called from within a rcu read lock block.
914 static void mesh_queue_preq(struct mesh_path *mpath, u8 flags)
916 struct ieee80211_sub_if_data *sdata = mpath->sdata;
917 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
918 struct mesh_preq_queue *preq_node;
920 preq_node = kmalloc(sizeof(struct mesh_preq_queue), GFP_ATOMIC);
922 mhwmp_dbg(sdata, "could not allocate PREQ node\n");
926 spin_lock_bh(&ifmsh->mesh_preq_queue_lock);
927 if (ifmsh->preq_queue_len == MAX_PREQ_QUEUE_LEN) {
928 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
930 if (printk_ratelimit())
931 mhwmp_dbg(sdata, "PREQ node queue full\n");
935 spin_lock(&mpath->state_lock);
936 if (mpath->flags & MESH_PATH_REQ_QUEUED) {
937 spin_unlock(&mpath->state_lock);
938 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
943 memcpy(preq_node->dst, mpath->dst, ETH_ALEN);
944 preq_node->flags = flags;
946 mpath->flags |= MESH_PATH_REQ_QUEUED;
947 spin_unlock(&mpath->state_lock);
949 list_add_tail(&preq_node->list, &ifmsh->preq_queue.list);
950 ++ifmsh->preq_queue_len;
951 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
953 if (time_after(jiffies, ifmsh->last_preq + min_preq_int_jiff(sdata)))
954 ieee80211_queue_work(&sdata->local->hw, &sdata->work);
956 else if (time_before(jiffies, ifmsh->last_preq)) {
957 /* avoid long wait if did not send preqs for a long time
958 * and jiffies wrapped around
960 ifmsh->last_preq = jiffies - min_preq_int_jiff(sdata) - 1;
961 ieee80211_queue_work(&sdata->local->hw, &sdata->work);
963 mod_timer(&ifmsh->mesh_path_timer, ifmsh->last_preq +
964 min_preq_int_jiff(sdata));
968 * mesh_path_start_discovery - launch a path discovery from the PREQ queue
970 * @sdata: local mesh subif
972 void mesh_path_start_discovery(struct ieee80211_sub_if_data *sdata)
974 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
975 struct mesh_preq_queue *preq_node;
976 struct mesh_path *mpath;
977 u8 ttl, target_flags;
981 spin_lock_bh(&ifmsh->mesh_preq_queue_lock);
982 if (!ifmsh->preq_queue_len ||
983 time_before(jiffies, ifmsh->last_preq +
984 min_preq_int_jiff(sdata))) {
985 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
989 preq_node = list_first_entry(&ifmsh->preq_queue.list,
990 struct mesh_preq_queue, list);
991 list_del(&preq_node->list);
992 --ifmsh->preq_queue_len;
993 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
996 mpath = mesh_path_lookup(sdata, preq_node->dst);
1000 spin_lock_bh(&mpath->state_lock);
1001 mpath->flags &= ~MESH_PATH_REQ_QUEUED;
1002 if (preq_node->flags & PREQ_Q_F_START) {
1003 if (mpath->flags & MESH_PATH_RESOLVING) {
1004 spin_unlock_bh(&mpath->state_lock);
1007 mpath->flags &= ~MESH_PATH_RESOLVED;
1008 mpath->flags |= MESH_PATH_RESOLVING;
1009 mpath->discovery_retries = 0;
1010 mpath->discovery_timeout = disc_timeout_jiff(sdata);
1012 } else if (!(mpath->flags & MESH_PATH_RESOLVING) ||
1013 mpath->flags & MESH_PATH_RESOLVED) {
1014 mpath->flags &= ~MESH_PATH_RESOLVING;
1015 spin_unlock_bh(&mpath->state_lock);
1019 ifmsh->last_preq = jiffies;
1021 if (time_after(jiffies, ifmsh->last_sn_update +
1022 net_traversal_jiffies(sdata)) ||
1023 time_before(jiffies, ifmsh->last_sn_update)) {
1025 sdata->u.mesh.last_sn_update = jiffies;
1027 lifetime = default_lifetime(sdata);
1028 ttl = sdata->u.mesh.mshcfg.element_ttl;
1030 sdata->u.mesh.mshstats.dropped_frames_ttl++;
1031 spin_unlock_bh(&mpath->state_lock);
1035 if (preq_node->flags & PREQ_Q_F_REFRESH)
1036 target_flags = MP_F_DO;
1038 target_flags = MP_F_RF;
1040 spin_unlock_bh(&mpath->state_lock);
1041 da = (mpath->is_root) ? mpath->rann_snd_addr : broadcast_addr;
1042 mesh_path_sel_frame_tx(MPATH_PREQ, 0, sdata->vif.addr, ifmsh->sn,
1043 target_flags, mpath->dst, mpath->sn, da, 0,
1044 ttl, lifetime, 0, ifmsh->preq_id++, sdata);
1045 mod_timer(&mpath->timer, jiffies + mpath->discovery_timeout);
1053 * mesh_nexthop_resolve - lookup next hop; conditionally start path discovery
1055 * @skb: 802.11 frame to be sent
1056 * @sdata: network subif the frame will be sent through
1058 * Lookup next hop for given skb and start path discovery if no
1059 * forwarding information is found.
1061 * Returns: 0 if the next hop was found and -ENOENT if the frame was queued.
1062 * skb is freeed here if no mpath could be allocated.
1064 int mesh_nexthop_resolve(struct ieee80211_sub_if_data *sdata,
1065 struct sk_buff *skb)
1067 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1068 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1069 struct mesh_path *mpath;
1070 struct sk_buff *skb_to_free = NULL;
1071 u8 *target_addr = hdr->addr3;
1074 /* Nulls are only sent to peers for PS and should be pre-addressed */
1075 if (ieee80211_is_qos_nullfunc(hdr->frame_control))
1079 err = mesh_nexthop_lookup(sdata, skb);
1083 /* no nexthop found, start resolving */
1084 mpath = mesh_path_lookup(sdata, target_addr);
1086 mpath = mesh_path_add(sdata, target_addr);
1087 if (IS_ERR(mpath)) {
1088 mesh_path_discard_frame(sdata, skb);
1089 err = PTR_ERR(mpath);
1094 if (!(mpath->flags & MESH_PATH_RESOLVING))
1095 mesh_queue_preq(mpath, PREQ_Q_F_START);
1097 if (skb_queue_len(&mpath->frame_queue) >= MESH_FRAME_QUEUE_LEN)
1098 skb_to_free = skb_dequeue(&mpath->frame_queue);
1100 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1101 ieee80211_set_qos_hdr(sdata, skb);
1102 skb_queue_tail(&mpath->frame_queue, skb);
1105 mesh_path_discard_frame(sdata, skb_to_free);
1113 * mesh_nexthop_lookup - put the appropriate next hop on a mesh frame. Calling
1114 * this function is considered "using" the associated mpath, so preempt a path
1115 * refresh if this mpath expires soon.
1117 * @skb: 802.11 frame to be sent
1118 * @sdata: network subif the frame will be sent through
1120 * Returns: 0 if the next hop was found. Nonzero otherwise.
1122 int mesh_nexthop_lookup(struct ieee80211_sub_if_data *sdata,
1123 struct sk_buff *skb)
1125 struct mesh_path *mpath;
1126 struct sta_info *next_hop;
1127 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1128 u8 *target_addr = hdr->addr3;
1132 mpath = mesh_path_lookup(sdata, target_addr);
1134 if (!mpath || !(mpath->flags & MESH_PATH_ACTIVE))
1137 if (time_after(jiffies,
1139 msecs_to_jiffies(sdata->u.mesh.mshcfg.path_refresh_time)) &&
1140 ether_addr_equal(sdata->vif.addr, hdr->addr4) &&
1141 !(mpath->flags & MESH_PATH_RESOLVING) &&
1142 !(mpath->flags & MESH_PATH_FIXED))
1143 mesh_queue_preq(mpath, PREQ_Q_F_START | PREQ_Q_F_REFRESH);
1145 next_hop = rcu_dereference(mpath->next_hop);
1147 memcpy(hdr->addr1, next_hop->sta.addr, ETH_ALEN);
1148 memcpy(hdr->addr2, sdata->vif.addr, ETH_ALEN);
1149 ieee80211_mps_set_frame_flags(sdata, next_hop, hdr);
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);
1191 void mesh_path_tx_root_frame(struct ieee80211_sub_if_data *sdata)
1193 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1194 u32 interval = ifmsh->mshcfg.dot11MeshHWMPRannInterval;
1195 u8 flags, target_flags = 0;
1197 flags = (ifmsh->mshcfg.dot11MeshGateAnnouncementProtocol)
1198 ? RANN_FLAG_IS_GATE : 0;
1200 switch (ifmsh->mshcfg.dot11MeshHWMPRootMode) {
1201 case IEEE80211_PROACTIVE_RANN:
1202 mesh_path_sel_frame_tx(MPATH_RANN, flags, sdata->vif.addr,
1203 ++ifmsh->sn, 0, NULL, 0, broadcast_addr,
1204 0, ifmsh->mshcfg.element_ttl,
1205 interval, 0, 0, sdata);
1207 case IEEE80211_PROACTIVE_PREQ_WITH_PREP:
1208 flags |= IEEE80211_PREQ_PROACTIVE_PREP_FLAG;
1209 case IEEE80211_PROACTIVE_PREQ_NO_PREP:
1210 interval = ifmsh->mshcfg.dot11MeshHWMPactivePathToRootTimeout;
1211 target_flags |= IEEE80211_PREQ_TO_FLAG |
1212 IEEE80211_PREQ_USN_FLAG;
1213 mesh_path_sel_frame_tx(MPATH_PREQ, flags, sdata->vif.addr,
1214 ++ifmsh->sn, target_flags,
1215 (u8 *) broadcast_addr, 0, broadcast_addr,
1216 0, ifmsh->mshcfg.element_ttl, interval,
1217 0, ifmsh->preq_id++, sdata);
1220 mhwmp_dbg(sdata, "Proactive mechanism not supported\n");