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 u32 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, __le32 orig_sn,
106 u8 target_flags, const u8 *target,
107 __le32 target_sn, const u8 *da,
108 u8 hop_count, u8 ttl,
109 __le32 lifetime, __le32 metric,
111 struct ieee80211_sub_if_data *sdata)
113 struct ieee80211_local *local = sdata->local;
115 struct ieee80211_mgmt *mgmt;
117 int hdr_len = offsetof(struct ieee80211_mgmt, u.action.u.mesh_action) +
118 sizeof(mgmt->u.action.u.mesh_action);
120 skb = dev_alloc_skb(local->tx_headroom +
122 2 + 37); /* max HWMP IE */
125 skb_reserve(skb, local->tx_headroom);
126 mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len);
127 memset(mgmt, 0, hdr_len);
128 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
129 IEEE80211_STYPE_ACTION);
131 memcpy(mgmt->da, da, ETH_ALEN);
132 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
134 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
135 mgmt->u.action.category = WLAN_CATEGORY_MESH_ACTION;
136 mgmt->u.action.u.mesh_action.action_code =
137 WLAN_MESH_ACTION_HWMP_PATH_SELECTION;
141 mhwmp_dbg(sdata, "sending PREQ to %pM\n", target);
143 pos = skb_put(skb, 2 + ie_len);
144 *pos++ = WLAN_EID_PREQ;
147 mhwmp_dbg(sdata, "sending PREP to %pM\n", target);
149 pos = skb_put(skb, 2 + ie_len);
150 *pos++ = WLAN_EID_PREP;
153 mhwmp_dbg(sdata, "sending RANN from %pM\n", orig_addr);
154 ie_len = sizeof(struct ieee80211_rann_ie);
155 pos = skb_put(skb, 2 + ie_len);
156 *pos++ = WLAN_EID_RANN;
167 if (action == MPATH_PREP) {
168 memcpy(pos, target, ETH_ALEN);
170 memcpy(pos, &target_sn, 4);
173 if (action == MPATH_PREQ) {
174 memcpy(pos, &preq_id, 4);
177 memcpy(pos, orig_addr, ETH_ALEN);
179 memcpy(pos, &orig_sn, 4);
182 memcpy(pos, &lifetime, 4); /* interval for RANN */
184 memcpy(pos, &metric, 4);
186 if (action == MPATH_PREQ) {
187 *pos++ = 1; /* destination count */
188 *pos++ = target_flags;
189 memcpy(pos, target, ETH_ALEN);
191 memcpy(pos, &target_sn, 4);
193 } else if (action == MPATH_PREP) {
194 memcpy(pos, orig_addr, ETH_ALEN);
196 memcpy(pos, &orig_sn, 4);
200 ieee80211_tx_skb(sdata, skb);
205 /* Headroom is not adjusted. Caller should ensure that skb has sufficient
206 * headroom in case the frame is encrypted. */
207 static void prepare_frame_for_deferred_tx(struct ieee80211_sub_if_data *sdata,
210 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
211 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
213 skb_set_mac_header(skb, 0);
214 skb_set_network_header(skb, 0);
215 skb_set_transport_header(skb, 0);
217 /* Send all internal mgmt frames on VO. Accordingly set TID to 7. */
218 skb_set_queue_mapping(skb, IEEE80211_AC_VO);
221 info->control.vif = &sdata->vif;
222 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
223 ieee80211_set_qos_hdr(sdata, skb);
224 ieee80211_mps_set_frame_flags(sdata, NULL, hdr);
228 * mesh_path_error_tx - Sends a PERR mesh management frame
230 * @ttl: allowed remaining hops
231 * @target: broken destination
232 * @target_sn: SN of the broken destination
233 * @target_rcode: reason code for this PERR
234 * @ra: node this frame is addressed to
235 * @sdata: local mesh subif
237 * Note: This function may be called with driver locks taken that the driver
238 * also acquires in the TX path. To avoid a deadlock we don't transmit the
239 * frame directly but add it to the pending queue instead.
241 int mesh_path_error_tx(u8 ttl, const u8 *target, __le32 target_sn,
242 __le16 target_rcode, const u8 *ra,
243 struct ieee80211_sub_if_data *sdata)
245 struct ieee80211_local *local = sdata->local;
247 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
248 struct ieee80211_mgmt *mgmt;
250 int hdr_len = offsetof(struct ieee80211_mgmt, u.action.u.mesh_action) +
251 sizeof(mgmt->u.action.u.mesh_action);
253 if (time_before(jiffies, ifmsh->next_perr))
256 skb = dev_alloc_skb(local->tx_headroom +
257 IEEE80211_ENCRYPT_HEADROOM +
258 IEEE80211_ENCRYPT_TAILROOM +
260 2 + 15 /* PERR IE */);
263 skb_reserve(skb, local->tx_headroom + IEEE80211_ENCRYPT_HEADROOM);
264 mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len);
265 memset(mgmt, 0, hdr_len);
266 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
267 IEEE80211_STYPE_ACTION);
269 memcpy(mgmt->da, ra, ETH_ALEN);
270 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
272 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
273 mgmt->u.action.category = WLAN_CATEGORY_MESH_ACTION;
274 mgmt->u.action.u.mesh_action.action_code =
275 WLAN_MESH_ACTION_HWMP_PATH_SELECTION;
277 pos = skb_put(skb, 2 + ie_len);
278 *pos++ = WLAN_EID_PERR;
282 /* number of destinations */
285 * flags bit, bit 1 is unset if we know the sequence number and
286 * bit 2 is set if we have a reason code
294 memcpy(pos, target, ETH_ALEN);
296 memcpy(pos, &target_sn, 4);
298 memcpy(pos, &target_rcode, 2);
300 /* see note in function header */
301 prepare_frame_for_deferred_tx(sdata, skb);
302 ifmsh->next_perr = TU_TO_EXP_TIME(
303 ifmsh->mshcfg.dot11MeshHWMPperrMinInterval);
304 ieee80211_add_pending_skb(local, skb);
308 void ieee80211s_update_metric(struct ieee80211_local *local,
309 struct sta_info *sta, struct sk_buff *skb)
311 struct ieee80211_tx_info *txinfo = IEEE80211_SKB_CB(skb);
312 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
315 if (!ieee80211_is_data(hdr->frame_control))
318 failed = !(txinfo->flags & IEEE80211_TX_STAT_ACK);
320 /* moving average, scaled to 100 */
321 sta->fail_avg = ((80 * sta->fail_avg + 5) / 100 + 20 * failed);
322 if (sta->fail_avg > 95)
323 mesh_plink_broken(sta);
326 static u32 airtime_link_metric_get(struct ieee80211_local *local,
327 struct sta_info *sta)
329 struct rate_info rinfo;
330 /* This should be adjusted for each device */
331 int device_constant = 1 << ARITH_SHIFT;
332 int test_frame_len = TEST_FRAME_LEN << ARITH_SHIFT;
333 int s_unit = 1 << ARITH_SHIFT;
335 u32 tx_time, estimated_retx;
338 if (sta->fail_avg >= 100)
341 sta_set_rate_info_tx(sta, &sta->last_tx_rate, &rinfo);
342 rate = cfg80211_calculate_bitrate(&rinfo);
346 err = (sta->fail_avg << ARITH_SHIFT) / 100;
348 /* bitrate is in units of 100 Kbps, while we need rate in units of
349 * 1Mbps. This will be corrected on tx_time computation.
351 tx_time = (device_constant + 10 * test_frame_len / rate);
352 estimated_retx = ((1 << (2 * ARITH_SHIFT)) / (s_unit - err));
353 result = (tx_time * estimated_retx) >> (2 * ARITH_SHIFT) ;
358 * hwmp_route_info_get - Update routing info to originator and transmitter
360 * @sdata: local mesh subif
361 * @mgmt: mesh management frame
362 * @hwmp_ie: hwmp information element (PREP or PREQ)
363 * @action: type of hwmp ie
365 * This function updates the path routing information to the originator and the
366 * transmitter of a HWMP PREQ or PREP frame.
368 * Returns: metric to frame originator or 0 if the frame should not be further
371 * Notes: this function is the only place (besides user-provided info) where
372 * path routing information is updated.
374 static u32 hwmp_route_info_get(struct ieee80211_sub_if_data *sdata,
375 struct ieee80211_mgmt *mgmt,
376 const u8 *hwmp_ie, enum mpath_frame_type action)
378 struct ieee80211_local *local = sdata->local;
379 struct mesh_path *mpath;
380 struct sta_info *sta;
382 const u8 *orig_addr, *ta;
383 u32 orig_sn, orig_metric;
384 unsigned long orig_lifetime, exp_time;
385 u32 last_hop_metric, new_metric;
389 sta = sta_info_get(sdata, mgmt->sa);
395 last_hop_metric = airtime_link_metric_get(local, sta);
396 /* Update and check originator routing info */
401 orig_addr = PREQ_IE_ORIG_ADDR(hwmp_ie);
402 orig_sn = PREQ_IE_ORIG_SN(hwmp_ie);
403 orig_lifetime = PREQ_IE_LIFETIME(hwmp_ie);
404 orig_metric = PREQ_IE_METRIC(hwmp_ie);
407 /* Originator here refers to the MP that was the target in the
408 * Path Request. We divert from the nomenclature in the draft
409 * so that we can easily use a single function to gather path
410 * information from both PREQ and PREP frames.
412 orig_addr = PREP_IE_TARGET_ADDR(hwmp_ie);
413 orig_sn = PREP_IE_TARGET_SN(hwmp_ie);
414 orig_lifetime = PREP_IE_LIFETIME(hwmp_ie);
415 orig_metric = PREP_IE_METRIC(hwmp_ie);
421 new_metric = orig_metric + last_hop_metric;
422 if (new_metric < orig_metric)
423 new_metric = MAX_METRIC;
424 exp_time = TU_TO_EXP_TIME(orig_lifetime);
426 if (ether_addr_equal(orig_addr, sdata->vif.addr)) {
427 /* This MP is the originator, we are not interested in this
428 * frame, except for updating transmitter's path info.
433 mpath = mesh_path_lookup(orig_addr, sdata);
435 spin_lock_bh(&mpath->state_lock);
436 if (mpath->flags & MESH_PATH_FIXED)
438 else if ((mpath->flags & MESH_PATH_ACTIVE) &&
439 (mpath->flags & MESH_PATH_SN_VALID)) {
440 if (SN_GT(mpath->sn, orig_sn) ||
441 (mpath->sn == orig_sn &&
442 new_metric >= mpath->metric)) {
448 mesh_path_add(orig_addr, sdata);
449 mpath = mesh_path_lookup(orig_addr, sdata);
454 spin_lock_bh(&mpath->state_lock);
458 mesh_path_assign_nexthop(mpath, sta);
459 mpath->flags |= MESH_PATH_SN_VALID;
460 mpath->metric = new_metric;
462 mpath->exp_time = time_after(mpath->exp_time, exp_time)
463 ? mpath->exp_time : exp_time;
464 mesh_path_activate(mpath);
465 spin_unlock_bh(&mpath->state_lock);
466 mesh_path_tx_pending(mpath);
467 /* draft says preq_id should be saved to, but there does
468 * not seem to be any use for it, skipping by now
471 spin_unlock_bh(&mpath->state_lock);
474 /* Update and check transmitter routing info */
476 if (ether_addr_equal(orig_addr, ta))
481 mpath = mesh_path_lookup(ta, sdata);
483 spin_lock_bh(&mpath->state_lock);
484 if ((mpath->flags & MESH_PATH_FIXED) ||
485 ((mpath->flags & MESH_PATH_ACTIVE) &&
486 (last_hop_metric > mpath->metric)))
489 mesh_path_add(ta, sdata);
490 mpath = mesh_path_lookup(ta, sdata);
495 spin_lock_bh(&mpath->state_lock);
499 mesh_path_assign_nexthop(mpath, sta);
500 mpath->metric = last_hop_metric;
501 mpath->exp_time = time_after(mpath->exp_time, exp_time)
502 ? mpath->exp_time : exp_time;
503 mesh_path_activate(mpath);
504 spin_unlock_bh(&mpath->state_lock);
505 mesh_path_tx_pending(mpath);
507 spin_unlock_bh(&mpath->state_lock);
512 return process ? new_metric : 0;
515 static void hwmp_preq_frame_process(struct ieee80211_sub_if_data *sdata,
516 struct ieee80211_mgmt *mgmt,
517 const u8 *preq_elem, u32 metric)
519 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
520 struct mesh_path *mpath = NULL;
521 const u8 *target_addr, *orig_addr;
523 u8 target_flags, ttl, flags;
524 u32 orig_sn, target_sn, lifetime, orig_metric;
529 /* Update target SN, if present */
530 target_addr = PREQ_IE_TARGET_ADDR(preq_elem);
531 orig_addr = PREQ_IE_ORIG_ADDR(preq_elem);
532 target_sn = PREQ_IE_TARGET_SN(preq_elem);
533 orig_sn = PREQ_IE_ORIG_SN(preq_elem);
534 target_flags = PREQ_IE_TARGET_F(preq_elem);
535 orig_metric = metric;
536 /* Proactive PREQ gate announcements */
537 flags = PREQ_IE_FLAGS(preq_elem);
538 root_is_gate = !!(flags & RANN_FLAG_IS_GATE);
540 mhwmp_dbg(sdata, "received PREQ from %pM\n", orig_addr);
542 if (ether_addr_equal(target_addr, sdata->vif.addr)) {
543 mhwmp_dbg(sdata, "PREQ is for us\n");
547 if (time_after(jiffies, ifmsh->last_sn_update +
548 net_traversal_jiffies(sdata)) ||
549 time_before(jiffies, ifmsh->last_sn_update)) {
550 target_sn = ++ifmsh->sn;
551 ifmsh->last_sn_update = jiffies;
553 } else if (is_broadcast_ether_addr(target_addr) &&
554 (target_flags & IEEE80211_PREQ_TO_FLAG)) {
556 mpath = mesh_path_lookup(orig_addr, sdata);
558 if (flags & IEEE80211_PREQ_PROACTIVE_PREP_FLAG) {
560 target_addr = sdata->vif.addr;
561 target_sn = ++ifmsh->sn;
563 ifmsh->last_sn_update = jiffies;
566 mesh_path_add_gate(mpath);
571 mpath = mesh_path_lookup(target_addr, sdata);
573 if ((!(mpath->flags & MESH_PATH_SN_VALID)) ||
574 SN_LT(mpath->sn, target_sn)) {
575 mpath->sn = target_sn;
576 mpath->flags |= MESH_PATH_SN_VALID;
577 } else if ((!(target_flags & MP_F_DO)) &&
578 (mpath->flags & MESH_PATH_ACTIVE)) {
580 metric = mpath->metric;
581 target_sn = mpath->sn;
582 if (target_flags & MP_F_RF)
583 target_flags |= MP_F_DO;
592 lifetime = PREQ_IE_LIFETIME(preq_elem);
593 ttl = ifmsh->mshcfg.element_ttl;
595 mhwmp_dbg(sdata, "replying to the PREQ\n");
596 mesh_path_sel_frame_tx(MPATH_PREP, 0, orig_addr,
597 cpu_to_le32(orig_sn), 0, target_addr,
598 cpu_to_le32(target_sn), mgmt->sa, 0, ttl,
599 cpu_to_le32(lifetime), cpu_to_le32(metric),
602 ifmsh->mshstats.dropped_frames_ttl++;
606 if (forward && ifmsh->mshcfg.dot11MeshForwarding) {
610 ttl = PREQ_IE_TTL(preq_elem);
611 lifetime = PREQ_IE_LIFETIME(preq_elem);
613 ifmsh->mshstats.dropped_frames_ttl++;
616 mhwmp_dbg(sdata, "forwarding the PREQ from %pM\n", orig_addr);
618 preq_id = PREQ_IE_PREQ_ID(preq_elem);
619 hopcount = PREQ_IE_HOPCOUNT(preq_elem) + 1;
620 da = (mpath && mpath->is_root) ?
621 mpath->rann_snd_addr : broadcast_addr;
623 if (flags & IEEE80211_PREQ_PROACTIVE_PREP_FLAG) {
624 target_addr = PREQ_IE_TARGET_ADDR(preq_elem);
625 target_sn = PREQ_IE_TARGET_SN(preq_elem);
626 metric = orig_metric;
629 mesh_path_sel_frame_tx(MPATH_PREQ, flags, orig_addr,
630 cpu_to_le32(orig_sn), target_flags, target_addr,
631 cpu_to_le32(target_sn), da,
632 hopcount, ttl, cpu_to_le32(lifetime),
633 cpu_to_le32(metric), cpu_to_le32(preq_id),
635 if (!is_multicast_ether_addr(da))
636 ifmsh->mshstats.fwded_unicast++;
638 ifmsh->mshstats.fwded_mcast++;
639 ifmsh->mshstats.fwded_frames++;
644 static inline struct sta_info *
645 next_hop_deref_protected(struct mesh_path *mpath)
647 return rcu_dereference_protected(mpath->next_hop,
648 lockdep_is_held(&mpath->state_lock));
652 static void hwmp_prep_frame_process(struct ieee80211_sub_if_data *sdata,
653 struct ieee80211_mgmt *mgmt,
654 const u8 *prep_elem, u32 metric)
656 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
657 struct mesh_path *mpath;
658 const u8 *target_addr, *orig_addr;
659 u8 ttl, hopcount, flags;
660 u8 next_hop[ETH_ALEN];
661 u32 target_sn, orig_sn, lifetime;
663 mhwmp_dbg(sdata, "received PREP from %pM\n",
664 PREP_IE_ORIG_ADDR(prep_elem));
666 orig_addr = PREP_IE_ORIG_ADDR(prep_elem);
667 if (ether_addr_equal(orig_addr, sdata->vif.addr))
668 /* destination, no forwarding required */
671 if (!ifmsh->mshcfg.dot11MeshForwarding)
674 ttl = PREP_IE_TTL(prep_elem);
676 sdata->u.mesh.mshstats.dropped_frames_ttl++;
681 mpath = mesh_path_lookup(orig_addr, sdata);
683 spin_lock_bh(&mpath->state_lock);
686 if (!(mpath->flags & MESH_PATH_ACTIVE)) {
687 spin_unlock_bh(&mpath->state_lock);
690 memcpy(next_hop, next_hop_deref_protected(mpath)->sta.addr, ETH_ALEN);
691 spin_unlock_bh(&mpath->state_lock);
693 flags = PREP_IE_FLAGS(prep_elem);
694 lifetime = PREP_IE_LIFETIME(prep_elem);
695 hopcount = PREP_IE_HOPCOUNT(prep_elem) + 1;
696 target_addr = PREP_IE_TARGET_ADDR(prep_elem);
697 target_sn = PREP_IE_TARGET_SN(prep_elem);
698 orig_sn = PREP_IE_ORIG_SN(prep_elem);
700 mesh_path_sel_frame_tx(MPATH_PREP, flags, orig_addr,
701 cpu_to_le32(orig_sn), 0, target_addr,
702 cpu_to_le32(target_sn), next_hop, hopcount,
703 ttl, cpu_to_le32(lifetime), cpu_to_le32(metric),
707 sdata->u.mesh.mshstats.fwded_unicast++;
708 sdata->u.mesh.mshstats.fwded_frames++;
713 sdata->u.mesh.mshstats.dropped_frames_no_route++;
716 static void hwmp_perr_frame_process(struct ieee80211_sub_if_data *sdata,
717 struct ieee80211_mgmt *mgmt,
720 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
721 struct mesh_path *mpath;
723 const u8 *ta, *target_addr;
728 ttl = PERR_IE_TTL(perr_elem);
730 ifmsh->mshstats.dropped_frames_ttl++;
734 target_addr = PERR_IE_TARGET_ADDR(perr_elem);
735 target_sn = PERR_IE_TARGET_SN(perr_elem);
736 target_rcode = PERR_IE_TARGET_RCODE(perr_elem);
739 mpath = mesh_path_lookup(target_addr, sdata);
741 struct sta_info *sta;
743 spin_lock_bh(&mpath->state_lock);
744 sta = next_hop_deref_protected(mpath);
745 if (mpath->flags & MESH_PATH_ACTIVE &&
746 ether_addr_equal(ta, sta->sta.addr) &&
747 (!(mpath->flags & MESH_PATH_SN_VALID) ||
748 SN_GT(target_sn, mpath->sn))) {
749 mpath->flags &= ~MESH_PATH_ACTIVE;
750 mpath->sn = target_sn;
751 spin_unlock_bh(&mpath->state_lock);
752 if (!ifmsh->mshcfg.dot11MeshForwarding)
754 mesh_path_error_tx(ttl, target_addr, cpu_to_le32(target_sn),
755 cpu_to_le16(target_rcode),
756 broadcast_addr, sdata);
758 spin_unlock_bh(&mpath->state_lock);
764 static void hwmp_rann_frame_process(struct ieee80211_sub_if_data *sdata,
765 struct ieee80211_mgmt *mgmt,
766 const struct ieee80211_rann_ie *rann)
768 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
769 struct ieee80211_local *local = sdata->local;
770 struct sta_info *sta;
771 struct mesh_path *mpath;
772 u8 ttl, flags, hopcount;
774 u32 orig_sn, metric, metric_txsta, interval;
777 ttl = rann->rann_ttl;
778 flags = rann->rann_flags;
779 root_is_gate = !!(flags & RANN_FLAG_IS_GATE);
780 orig_addr = rann->rann_addr;
781 orig_sn = le32_to_cpu(rann->rann_seq);
782 interval = le32_to_cpu(rann->rann_interval);
783 hopcount = rann->rann_hopcount;
785 metric = le32_to_cpu(rann->rann_metric);
787 /* Ignore our own RANNs */
788 if (ether_addr_equal(orig_addr, sdata->vif.addr))
792 "received RANN from %pM via neighbour %pM (is_gate=%d)\n",
793 orig_addr, mgmt->sa, root_is_gate);
796 sta = sta_info_get(sdata, mgmt->sa);
802 metric_txsta = airtime_link_metric_get(local, sta);
804 mpath = mesh_path_lookup(orig_addr, sdata);
806 mesh_path_add(orig_addr, sdata);
807 mpath = mesh_path_lookup(orig_addr, sdata);
810 sdata->u.mesh.mshstats.dropped_frames_no_route++;
815 if (!(SN_LT(mpath->sn, orig_sn)) &&
816 !(mpath->sn == orig_sn && metric < mpath->rann_metric)) {
821 if ((!(mpath->flags & (MESH_PATH_ACTIVE | MESH_PATH_RESOLVING)) ||
822 (time_after(jiffies, mpath->last_preq_to_root +
823 root_path_confirmation_jiffies(sdata)) ||
824 time_before(jiffies, mpath->last_preq_to_root))) &&
825 !(mpath->flags & MESH_PATH_FIXED) && (ttl != 0)) {
827 "time to refresh root mpath %pM\n",
829 mesh_queue_preq(mpath, PREQ_Q_F_START | PREQ_Q_F_REFRESH);
830 mpath->last_preq_to_root = jiffies;
834 mpath->rann_metric = metric + metric_txsta;
835 mpath->is_root = true;
836 /* Recording RANNs sender address to send individually
837 * addressed PREQs destined for root mesh STA */
838 memcpy(mpath->rann_snd_addr, mgmt->sa, ETH_ALEN);
841 mesh_path_add_gate(mpath);
844 ifmsh->mshstats.dropped_frames_ttl++;
850 if (ifmsh->mshcfg.dot11MeshForwarding) {
851 mesh_path_sel_frame_tx(MPATH_RANN, flags, orig_addr,
852 cpu_to_le32(orig_sn),
853 0, NULL, 0, broadcast_addr,
854 hopcount, ttl, cpu_to_le32(interval),
855 cpu_to_le32(metric + metric_txsta),
863 void mesh_rx_path_sel_frame(struct ieee80211_sub_if_data *sdata,
864 struct ieee80211_mgmt *mgmt,
867 struct ieee802_11_elems elems;
870 struct sta_info *sta;
872 /* need action_code */
873 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
877 sta = sta_info_get(sdata, mgmt->sa);
878 if (!sta || sta->plink_state != NL80211_PLINK_ESTAB) {
884 baselen = (u8 *) mgmt->u.action.u.mesh_action.variable - (u8 *) mgmt;
885 ieee802_11_parse_elems(mgmt->u.action.u.mesh_action.variable,
886 len - baselen, &elems);
889 if (elems.preq_len != 37)
890 /* Right now we support just 1 destination and no AE */
892 last_hop_metric = hwmp_route_info_get(sdata, mgmt, elems.preq,
895 hwmp_preq_frame_process(sdata, mgmt, elems.preq,
899 if (elems.prep_len != 31)
900 /* Right now we support no AE */
902 last_hop_metric = hwmp_route_info_get(sdata, mgmt, elems.prep,
905 hwmp_prep_frame_process(sdata, mgmt, elems.prep,
909 if (elems.perr_len != 15)
910 /* Right now we support only one destination per PERR */
912 hwmp_perr_frame_process(sdata, mgmt, elems.perr);
915 hwmp_rann_frame_process(sdata, mgmt, elems.rann);
919 * mesh_queue_preq - queue a PREQ to a given destination
921 * @mpath: mesh path to discover
922 * @flags: special attributes of the PREQ to be sent
924 * Locking: the function must be called from within a rcu read lock block.
927 static void mesh_queue_preq(struct mesh_path *mpath, u8 flags)
929 struct ieee80211_sub_if_data *sdata = mpath->sdata;
930 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
931 struct mesh_preq_queue *preq_node;
933 preq_node = kmalloc(sizeof(struct mesh_preq_queue), GFP_ATOMIC);
935 mhwmp_dbg(sdata, "could not allocate PREQ node\n");
939 spin_lock_bh(&ifmsh->mesh_preq_queue_lock);
940 if (ifmsh->preq_queue_len == MAX_PREQ_QUEUE_LEN) {
941 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
943 if (printk_ratelimit())
944 mhwmp_dbg(sdata, "PREQ node queue full\n");
948 spin_lock(&mpath->state_lock);
949 if (mpath->flags & MESH_PATH_REQ_QUEUED) {
950 spin_unlock(&mpath->state_lock);
951 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
956 memcpy(preq_node->dst, mpath->dst, ETH_ALEN);
957 preq_node->flags = flags;
959 mpath->flags |= MESH_PATH_REQ_QUEUED;
960 spin_unlock(&mpath->state_lock);
962 list_add_tail(&preq_node->list, &ifmsh->preq_queue.list);
963 ++ifmsh->preq_queue_len;
964 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
966 if (time_after(jiffies, ifmsh->last_preq + min_preq_int_jiff(sdata)))
967 ieee80211_queue_work(&sdata->local->hw, &sdata->work);
969 else if (time_before(jiffies, ifmsh->last_preq)) {
970 /* avoid long wait if did not send preqs for a long time
971 * and jiffies wrapped around
973 ifmsh->last_preq = jiffies - min_preq_int_jiff(sdata) - 1;
974 ieee80211_queue_work(&sdata->local->hw, &sdata->work);
976 mod_timer(&ifmsh->mesh_path_timer, ifmsh->last_preq +
977 min_preq_int_jiff(sdata));
981 * mesh_path_start_discovery - launch a path discovery from the PREQ queue
983 * @sdata: local mesh subif
985 void mesh_path_start_discovery(struct ieee80211_sub_if_data *sdata)
987 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
988 struct mesh_preq_queue *preq_node;
989 struct mesh_path *mpath;
990 u8 ttl, target_flags;
994 spin_lock_bh(&ifmsh->mesh_preq_queue_lock);
995 if (!ifmsh->preq_queue_len ||
996 time_before(jiffies, ifmsh->last_preq +
997 min_preq_int_jiff(sdata))) {
998 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
1002 preq_node = list_first_entry(&ifmsh->preq_queue.list,
1003 struct mesh_preq_queue, list);
1004 list_del(&preq_node->list);
1005 --ifmsh->preq_queue_len;
1006 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
1009 mpath = mesh_path_lookup(preq_node->dst, sdata);
1013 spin_lock_bh(&mpath->state_lock);
1014 mpath->flags &= ~MESH_PATH_REQ_QUEUED;
1015 if (preq_node->flags & PREQ_Q_F_START) {
1016 if (mpath->flags & MESH_PATH_RESOLVING) {
1017 spin_unlock_bh(&mpath->state_lock);
1020 mpath->flags &= ~MESH_PATH_RESOLVED;
1021 mpath->flags |= MESH_PATH_RESOLVING;
1022 mpath->discovery_retries = 0;
1023 mpath->discovery_timeout = disc_timeout_jiff(sdata);
1025 } else if (!(mpath->flags & MESH_PATH_RESOLVING) ||
1026 mpath->flags & MESH_PATH_RESOLVED) {
1027 mpath->flags &= ~MESH_PATH_RESOLVING;
1028 spin_unlock_bh(&mpath->state_lock);
1032 ifmsh->last_preq = jiffies;
1034 if (time_after(jiffies, ifmsh->last_sn_update +
1035 net_traversal_jiffies(sdata)) ||
1036 time_before(jiffies, ifmsh->last_sn_update)) {
1038 sdata->u.mesh.last_sn_update = jiffies;
1040 lifetime = default_lifetime(sdata);
1041 ttl = sdata->u.mesh.mshcfg.element_ttl;
1043 sdata->u.mesh.mshstats.dropped_frames_ttl++;
1044 spin_unlock_bh(&mpath->state_lock);
1048 if (preq_node->flags & PREQ_Q_F_REFRESH)
1049 target_flags = MP_F_DO;
1051 target_flags = MP_F_RF;
1053 spin_unlock_bh(&mpath->state_lock);
1054 da = (mpath->is_root) ? mpath->rann_snd_addr : broadcast_addr;
1055 mesh_path_sel_frame_tx(MPATH_PREQ, 0, sdata->vif.addr,
1056 cpu_to_le32(ifmsh->sn), target_flags, mpath->dst,
1057 cpu_to_le32(mpath->sn), da, 0,
1058 ttl, cpu_to_le32(lifetime), 0,
1059 cpu_to_le32(ifmsh->preq_id++), sdata);
1060 mod_timer(&mpath->timer, jiffies + mpath->discovery_timeout);
1068 * mesh_nexthop_resolve - lookup next hop; conditionally start path discovery
1070 * @skb: 802.11 frame to be sent
1071 * @sdata: network subif the frame will be sent through
1073 * Lookup next hop for given skb and start path discovery if no
1074 * forwarding information is found.
1076 * Returns: 0 if the next hop was found and -ENOENT if the frame was queued.
1077 * skb is freeed here if no mpath could be allocated.
1079 int mesh_nexthop_resolve(struct sk_buff *skb,
1080 struct ieee80211_sub_if_data *sdata)
1082 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1083 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1084 struct mesh_path *mpath;
1085 struct sk_buff *skb_to_free = NULL;
1086 u8 *target_addr = hdr->addr3;
1089 /* Nulls are only sent to peers for PS and should be pre-addressed */
1090 if (ieee80211_is_qos_nullfunc(hdr->frame_control))
1094 err = mesh_nexthop_lookup(skb, sdata);
1098 /* no nexthop found, start resolving */
1099 mpath = mesh_path_lookup(target_addr, sdata);
1101 mesh_path_add(target_addr, sdata);
1102 mpath = mesh_path_lookup(target_addr, sdata);
1104 mesh_path_discard_frame(skb, sdata);
1110 if (!(mpath->flags & MESH_PATH_RESOLVING))
1111 mesh_queue_preq(mpath, PREQ_Q_F_START);
1113 if (skb_queue_len(&mpath->frame_queue) >= MESH_FRAME_QUEUE_LEN)
1114 skb_to_free = skb_dequeue(&mpath->frame_queue);
1116 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1117 ieee80211_set_qos_hdr(sdata, skb);
1118 skb_queue_tail(&mpath->frame_queue, skb);
1121 mesh_path_discard_frame(skb_to_free, sdata);
1128 * mesh_nexthop_lookup - put the appropriate next hop on a mesh frame. Calling
1129 * this function is considered "using" the associated mpath, so preempt a path
1130 * refresh if this mpath expires soon.
1132 * @skb: 802.11 frame to be sent
1133 * @sdata: network subif the frame will be sent through
1135 * Returns: 0 if the next hop was found. Nonzero otherwise.
1137 int mesh_nexthop_lookup(struct sk_buff *skb,
1138 struct ieee80211_sub_if_data *sdata)
1140 struct mesh_path *mpath;
1141 struct sta_info *next_hop;
1142 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1143 u8 *target_addr = hdr->addr3;
1147 mpath = mesh_path_lookup(target_addr, sdata);
1149 if (!mpath || !(mpath->flags & MESH_PATH_ACTIVE))
1152 if (time_after(jiffies,
1154 msecs_to_jiffies(sdata->u.mesh.mshcfg.path_refresh_time)) &&
1155 ether_addr_equal(sdata->vif.addr, hdr->addr4) &&
1156 !(mpath->flags & MESH_PATH_RESOLVING) &&
1157 !(mpath->flags & MESH_PATH_FIXED))
1158 mesh_queue_preq(mpath, PREQ_Q_F_START | PREQ_Q_F_REFRESH);
1160 next_hop = rcu_dereference(mpath->next_hop);
1162 memcpy(hdr->addr1, next_hop->sta.addr, ETH_ALEN);
1163 memcpy(hdr->addr2, sdata->vif.addr, ETH_ALEN);
1164 ieee80211_mps_set_frame_flags(sdata, next_hop, hdr);
1173 void mesh_path_timer(unsigned long data)
1175 struct mesh_path *mpath = (void *) data;
1176 struct ieee80211_sub_if_data *sdata = mpath->sdata;
1179 if (sdata->local->quiescing)
1182 spin_lock_bh(&mpath->state_lock);
1183 if (mpath->flags & MESH_PATH_RESOLVED ||
1184 (!(mpath->flags & MESH_PATH_RESOLVING))) {
1185 mpath->flags &= ~(MESH_PATH_RESOLVING | MESH_PATH_RESOLVED);
1186 spin_unlock_bh(&mpath->state_lock);
1187 } else if (mpath->discovery_retries < max_preq_retries(sdata)) {
1188 ++mpath->discovery_retries;
1189 mpath->discovery_timeout *= 2;
1190 mpath->flags &= ~MESH_PATH_REQ_QUEUED;
1191 spin_unlock_bh(&mpath->state_lock);
1192 mesh_queue_preq(mpath, 0);
1195 mpath->exp_time = jiffies;
1196 spin_unlock_bh(&mpath->state_lock);
1197 if (!mpath->is_gate && mesh_gate_num(sdata) > 0) {
1198 ret = mesh_path_send_to_gates(mpath);
1200 mhwmp_dbg(sdata, "no gate was reachable\n");
1202 mesh_path_flush_pending(mpath);
1207 mesh_path_tx_root_frame(struct ieee80211_sub_if_data *sdata)
1209 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1210 u32 interval = ifmsh->mshcfg.dot11MeshHWMPRannInterval;
1211 u8 flags, target_flags = 0;
1213 flags = (ifmsh->mshcfg.dot11MeshGateAnnouncementProtocol)
1214 ? RANN_FLAG_IS_GATE : 0;
1216 switch (ifmsh->mshcfg.dot11MeshHWMPRootMode) {
1217 case IEEE80211_PROACTIVE_RANN:
1218 mesh_path_sel_frame_tx(MPATH_RANN, flags, sdata->vif.addr,
1219 cpu_to_le32(++ifmsh->sn),
1220 0, NULL, 0, broadcast_addr,
1221 0, ifmsh->mshcfg.element_ttl,
1222 cpu_to_le32(interval), 0, 0, sdata);
1224 case IEEE80211_PROACTIVE_PREQ_WITH_PREP:
1225 flags |= IEEE80211_PREQ_PROACTIVE_PREP_FLAG;
1226 case IEEE80211_PROACTIVE_PREQ_NO_PREP:
1227 interval = ifmsh->mshcfg.dot11MeshHWMPactivePathToRootTimeout;
1228 target_flags |= IEEE80211_PREQ_TO_FLAG |
1229 IEEE80211_PREQ_USN_FLAG;
1230 mesh_path_sel_frame_tx(MPATH_PREQ, flags, sdata->vif.addr,
1231 cpu_to_le32(++ifmsh->sn), target_flags,
1232 (u8 *) broadcast_addr, 0, broadcast_addr,
1233 0, ifmsh->mshcfg.element_ttl,
1234 cpu_to_le32(interval),
1235 0, cpu_to_le32(ifmsh->preq_id++), sdata);
1238 mhwmp_dbg(sdata, "Proactive mechanism not supported\n");