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perf scripts python: call-graph-from-sql.py: Provide better default column sizes
[linux/fpc-iii.git] / net / mac80211 / mesh_hwmp.c
blob6950cd0bf5940a0bc76ea0f3bc283c4a1cac7963
1 /*
2 * Copyright (c) 2008, 2009 open80211s Ltd.
3 * Author: Luis Carlos Cobo <luisca@cozybit.com>
4 *
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.
8 */
9
10 #include <linux/slab.h>
11 #include <linux/etherdevice.h>
12 #include <asm/unaligned.h>
13 #include "wme.h"
14 #include "mesh.h"
15
16 #define TEST_FRAME_LEN 8192
17 #define MAX_METRIC 0xffffffff
18 #define ARITH_SHIFT 8
19 #define LINK_FAIL_THRESH 95
20
21 #define MAX_PREQ_QUEUE_LEN 64
22
23 static void mesh_queue_preq(struct mesh_path *, u8);
24
25 static inline u32 u32_field_get(const u8 *preq_elem, int offset, bool ae)
26 {
27 if (ae)
28 offset += 6;
29 return get_unaligned_le32(preq_elem + offset);
30 }
31
32 static inline u16 u16_field_get(const u8 *preq_elem, int offset, bool ae)
33 {
34 if (ae)
35 offset += 6;
36 return get_unaligned_le16(preq_elem + offset);
37 }
38
39 /* HWMP IE processing macros */
40 #define AE_F (1<<6)
41 #define AE_F_SET(x) (*x & AE_F)
42 #define PREQ_IE_FLAGS(x) (*(x))
43 #define PREQ_IE_HOPCOUNT(x) (*(x + 1))
44 #define PREQ_IE_TTL(x) (*(x + 2))
45 #define PREQ_IE_PREQ_ID(x) u32_field_get(x, 3, 0)
46 #define PREQ_IE_ORIG_ADDR(x) (x + 7)
47 #define PREQ_IE_ORIG_SN(x) u32_field_get(x, 13, 0)
48 #define PREQ_IE_LIFETIME(x) u32_field_get(x, 17, AE_F_SET(x))
49 #define PREQ_IE_METRIC(x) u32_field_get(x, 21, AE_F_SET(x))
50 #define PREQ_IE_TARGET_F(x) (*(AE_F_SET(x) ? x + 32 : x + 26))
51 #define PREQ_IE_TARGET_ADDR(x) (AE_F_SET(x) ? x + 33 : x + 27)
52 #define PREQ_IE_TARGET_SN(x) u32_field_get(x, 33, AE_F_SET(x))
53
54
55 #define PREP_IE_FLAGS(x) PREQ_IE_FLAGS(x)
56 #define PREP_IE_HOPCOUNT(x) PREQ_IE_HOPCOUNT(x)
57 #define PREP_IE_TTL(x) PREQ_IE_TTL(x)
58 #define PREP_IE_ORIG_ADDR(x) (AE_F_SET(x) ? x + 27 : x + 21)
59 #define PREP_IE_ORIG_SN(x) u32_field_get(x, 27, AE_F_SET(x))
60 #define PREP_IE_LIFETIME(x) u32_field_get(x, 13, AE_F_SET(x))
61 #define PREP_IE_METRIC(x) u32_field_get(x, 17, AE_F_SET(x))
62 #define PREP_IE_TARGET_ADDR(x) (x + 3)
63 #define PREP_IE_TARGET_SN(x) u32_field_get(x, 9, 0)
64
65 #define PERR_IE_TTL(x) (*(x))
66 #define PERR_IE_TARGET_FLAGS(x) (*(x + 2))
67 #define PERR_IE_TARGET_ADDR(x) (x + 3)
68 #define PERR_IE_TARGET_SN(x) u32_field_get(x, 9, 0)
69 #define PERR_IE_TARGET_RCODE(x) u16_field_get(x, 13, 0)
70
71 #define MSEC_TO_TU(x) (x*1000/1024)
72 #define SN_GT(x, y) ((s32)(y - x) < 0)
73 #define SN_LT(x, y) ((s32)(x - y) < 0)
74 #define MAX_SANE_SN_DELTA 32
75
76 static inline u32 SN_DELTA(u32 x, u32 y)
77 {
78 return x >= y ? x - y : y - x;
79 }
80
81 #define net_traversal_jiffies(s) \
82 msecs_to_jiffies(s->u.mesh.mshcfg.dot11MeshHWMPnetDiameterTraversalTime)
83 #define default_lifetime(s) \
84 MSEC_TO_TU(s->u.mesh.mshcfg.dot11MeshHWMPactivePathTimeout)
85 #define min_preq_int_jiff(s) \
86 (msecs_to_jiffies(s->u.mesh.mshcfg.dot11MeshHWMPpreqMinInterval))
87 #define max_preq_retries(s) (s->u.mesh.mshcfg.dot11MeshHWMPmaxPREQretries)
88 #define disc_timeout_jiff(s) \
89 msecs_to_jiffies(sdata->u.mesh.mshcfg.min_discovery_timeout)
90 #define root_path_confirmation_jiffies(s) \
91 msecs_to_jiffies(sdata->u.mesh.mshcfg.dot11MeshHWMPconfirmationInterval)
92
93 enum mpath_frame_type {
94 MPATH_PREQ = 0,
95 MPATH_PREP,
96 MPATH_PERR,
97 MPATH_RANN
98 };
99
100 static const u8 broadcast_addr[ETH_ALEN] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
101
102 static int mesh_path_sel_frame_tx(enum mpath_frame_type action, u8 flags,
103 const u8 *orig_addr, u32 orig_sn,
104 u8 target_flags, const u8 *target,
105 u32 target_sn, const u8 *da,
106 u8 hop_count, u8 ttl,
107 u32 lifetime, u32 metric, u32 preq_id,
108 struct ieee80211_sub_if_data *sdata)
109 {
110 struct ieee80211_local *local = sdata->local;
111 struct sk_buff *skb;
112 struct ieee80211_mgmt *mgmt;
113 u8 *pos, ie_len;
114 int hdr_len = offsetofend(struct ieee80211_mgmt,
115 u.action.u.mesh_action);
116
117 skb = dev_alloc_skb(local->tx_headroom +
118 hdr_len +
119 2 + 37); /* max HWMP IE */
120 if (!skb)
121 return -1;
122 skb_reserve(skb, local->tx_headroom);
123 mgmt = skb_put_zero(skb, hdr_len);
124 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
125 IEEE80211_STYPE_ACTION);
126
127 memcpy(mgmt->da, da, ETH_ALEN);
128 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
129 /* BSSID == SA */
130 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
131 mgmt->u.action.category = WLAN_CATEGORY_MESH_ACTION;
132 mgmt->u.action.u.mesh_action.action_code =
133 WLAN_MESH_ACTION_HWMP_PATH_SELECTION;
134
135 switch (action) {
136 case MPATH_PREQ:
137 mhwmp_dbg(sdata, "sending PREQ to %pM\n", target);
138 ie_len = 37;
139 pos = skb_put(skb, 2 + ie_len);
140 *pos++ = WLAN_EID_PREQ;
141 break;
142 case MPATH_PREP:
143 mhwmp_dbg(sdata, "sending PREP to %pM\n", orig_addr);
144 ie_len = 31;
145 pos = skb_put(skb, 2 + ie_len);
146 *pos++ = WLAN_EID_PREP;
147 break;
148 case MPATH_RANN:
149 mhwmp_dbg(sdata, "sending RANN from %pM\n", orig_addr);
150 ie_len = sizeof(struct ieee80211_rann_ie);
151 pos = skb_put(skb, 2 + ie_len);
152 *pos++ = WLAN_EID_RANN;
153 break;
154 default:
155 kfree_skb(skb);
156 return -ENOTSUPP;
157 }
158 *pos++ = ie_len;
159 *pos++ = flags;
160 *pos++ = hop_count;
161 *pos++ = ttl;
162 if (action == MPATH_PREP) {
163 memcpy(pos, target, ETH_ALEN);
164 pos += ETH_ALEN;
165 put_unaligned_le32(target_sn, pos);
166 pos += 4;
167 } else {
168 if (action == MPATH_PREQ) {
169 put_unaligned_le32(preq_id, pos);
170 pos += 4;
171 }
172 memcpy(pos, orig_addr, ETH_ALEN);
173 pos += ETH_ALEN;
174 put_unaligned_le32(orig_sn, pos);
175 pos += 4;
176 }
177 put_unaligned_le32(lifetime, pos); /* interval for RANN */
178 pos += 4;
179 put_unaligned_le32(metric, pos);
180 pos += 4;
181 if (action == MPATH_PREQ) {
182 *pos++ = 1; /* destination count */
183 *pos++ = target_flags;
184 memcpy(pos, target, ETH_ALEN);
185 pos += ETH_ALEN;
186 put_unaligned_le32(target_sn, pos);
187 pos += 4;
188 } else if (action == MPATH_PREP) {
189 memcpy(pos, orig_addr, ETH_ALEN);
190 pos += ETH_ALEN;
191 put_unaligned_le32(orig_sn, pos);
192 pos += 4;
193 }
194
195 ieee80211_tx_skb(sdata, skb);
196 return 0;
197 }
198
199
200 /* Headroom is not adjusted. Caller should ensure that skb has sufficient
201 * headroom in case the frame is encrypted. */
202 static void prepare_frame_for_deferred_tx(struct ieee80211_sub_if_data *sdata,
203 struct sk_buff *skb)
204 {
205 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
206 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
207
208 skb_reset_mac_header(skb);
209 skb_reset_network_header(skb);
210 skb_reset_transport_header(skb);
211
212 /* Send all internal mgmt frames on VO. Accordingly set TID to 7. */
213 skb_set_queue_mapping(skb, IEEE80211_AC_VO);
214 skb->priority = 7;
215
216 info->control.vif = &sdata->vif;
217 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
218 ieee80211_set_qos_hdr(sdata, skb);
219 ieee80211_mps_set_frame_flags(sdata, NULL, hdr);
220 }
221
222 /**
223 * mesh_path_error_tx - Sends a PERR mesh management frame
224 *
225 * @ttl: allowed remaining hops
226 * @target: broken destination
227 * @target_sn: SN of the broken destination
228 * @target_rcode: reason code for this PERR
229 * @ra: node this frame is addressed to
230 * @sdata: local mesh subif
231 *
232 * Note: This function may be called with driver locks taken that the driver
233 * also acquires in the TX path. To avoid a deadlock we don't transmit the
234 * frame directly but add it to the pending queue instead.
235 */
236 int mesh_path_error_tx(struct ieee80211_sub_if_data *sdata,
237 u8 ttl, const u8 *target, u32 target_sn,
238 u16 target_rcode, const u8 *ra)
239 {
240 struct ieee80211_local *local = sdata->local;
241 struct sk_buff *skb;
242 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
243 struct ieee80211_mgmt *mgmt;
244 u8 *pos, ie_len;
245 int hdr_len = offsetofend(struct ieee80211_mgmt,
246 u.action.u.mesh_action);
247
248 if (time_before(jiffies, ifmsh->next_perr))
249 return -EAGAIN;
250
251 skb = dev_alloc_skb(local->tx_headroom +
252 sdata->encrypt_headroom +
253 IEEE80211_ENCRYPT_TAILROOM +
254 hdr_len +
255 2 + 15 /* PERR IE */);
256 if (!skb)
257 return -1;
258 skb_reserve(skb, local->tx_headroom + sdata->encrypt_headroom);
259 mgmt = skb_put_zero(skb, hdr_len);
260 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
261 IEEE80211_STYPE_ACTION);
262
263 memcpy(mgmt->da, ra, ETH_ALEN);
264 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
265 /* BSSID == SA */
266 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
267 mgmt->u.action.category = WLAN_CATEGORY_MESH_ACTION;
268 mgmt->u.action.u.mesh_action.action_code =
269 WLAN_MESH_ACTION_HWMP_PATH_SELECTION;
270 ie_len = 15;
271 pos = skb_put(skb, 2 + ie_len);
272 *pos++ = WLAN_EID_PERR;
273 *pos++ = ie_len;
274 /* ttl */
275 *pos++ = ttl;
276 /* number of destinations */
277 *pos++ = 1;
278 /* Flags field has AE bit only as defined in
279 * sec 8.4.2.117 IEEE802.11-2012
280 */
281 *pos = 0;
282 pos++;
283 memcpy(pos, target, ETH_ALEN);
284 pos += ETH_ALEN;
285 put_unaligned_le32(target_sn, pos);
286 pos += 4;
287 put_unaligned_le16(target_rcode, pos);
288
289 /* see note in function header */
290 prepare_frame_for_deferred_tx(sdata, skb);
291 ifmsh->next_perr = TU_TO_EXP_TIME(
292 ifmsh->mshcfg.dot11MeshHWMPperrMinInterval);
293 ieee80211_add_pending_skb(local, skb);
294 return 0;
295 }
296
297 void ieee80211s_update_metric(struct ieee80211_local *local,
298 struct sta_info *sta,
299 struct ieee80211_tx_status *st)
300 {
301 struct ieee80211_tx_info *txinfo = st->info;
302 int failed;
303
304 failed = !(txinfo->flags & IEEE80211_TX_STAT_ACK);
305
306 /* moving average, scaled to 100.
307 * feed failure as 100 and success as 0
308 */
309 ewma_mesh_fail_avg_add(&sta->mesh->fail_avg, failed * 100);
310 if (ewma_mesh_fail_avg_read(&sta->mesh->fail_avg) >
311 LINK_FAIL_THRESH)
312 mesh_plink_broken(sta);
313 }
314
315 static u32 airtime_link_metric_get(struct ieee80211_local *local,
316 struct sta_info *sta)
317 {
318 struct rate_info rinfo;
319 /* This should be adjusted for each device */
320 int device_constant = 1 << ARITH_SHIFT;
321 int test_frame_len = TEST_FRAME_LEN << ARITH_SHIFT;
322 int s_unit = 1 << ARITH_SHIFT;
323 int rate, err;
324 u32 tx_time, estimated_retx;
325 u64 result;
326 unsigned long fail_avg =
327 ewma_mesh_fail_avg_read(&sta->mesh->fail_avg);
328
329 /* Try to get rate based on HW/SW RC algorithm.
330 * Rate is returned in units of Kbps, correct this
331 * to comply with airtime calculation units
332 * Round up in case we get rate < 100Kbps
333 */
334 rate = DIV_ROUND_UP(sta_get_expected_throughput(sta), 100);
335
336 if (rate) {
337 err = 0;
338 } else {
339 if (fail_avg > LINK_FAIL_THRESH)
340 return MAX_METRIC;
341
342 sta_set_rate_info_tx(sta, &sta->tx_stats.last_rate, &rinfo);
343 rate = cfg80211_calculate_bitrate(&rinfo);
344 if (WARN_ON(!rate))
345 return MAX_METRIC;
346
347 err = (fail_avg << ARITH_SHIFT) / 100;
348 }
349
350 /* bitrate is in units of 100 Kbps, while we need rate in units of
351 * 1Mbps. This will be corrected on tx_time computation.
352 */
353 tx_time = (device_constant + 10 * test_frame_len / rate);
354 estimated_retx = ((1 << (2 * ARITH_SHIFT)) / (s_unit - err));
355 result = (tx_time * estimated_retx) >> (2 * ARITH_SHIFT);
356 return (u32)result;
357 }
358
359 /**
360 * hwmp_route_info_get - Update routing info to originator and transmitter
361 *
362 * @sdata: local mesh subif
363 * @mgmt: mesh management frame
364 * @hwmp_ie: hwmp information element (PREP or PREQ)
365 * @action: type of hwmp ie
366 *
367 * This function updates the path routing information to the originator and the
368 * transmitter of a HWMP PREQ or PREP frame.
369 *
370 * Returns: metric to frame originator or 0 if the frame should not be further
371 * processed
372 *
373 * Notes: this function is the only place (besides user-provided info) where
374 * path routing information is updated.
375 */
376 static u32 hwmp_route_info_get(struct ieee80211_sub_if_data *sdata,
377 struct ieee80211_mgmt *mgmt,
378 const u8 *hwmp_ie, enum mpath_frame_type action)
379 {
380 struct ieee80211_local *local = sdata->local;
381 struct mesh_path *mpath;
382 struct sta_info *sta;
383 bool fresh_info;
384 const u8 *orig_addr, *ta;
385 u32 orig_sn, orig_metric;
386 unsigned long orig_lifetime, exp_time;
387 u32 last_hop_metric, new_metric;
388 bool process = true;
389
390 rcu_read_lock();
391 sta = sta_info_get(sdata, mgmt->sa);
392 if (!sta) {
393 rcu_read_unlock();
394 return 0;
395 }
396
397 last_hop_metric = airtime_link_metric_get(local, sta);
398 /* Update and check originator routing info */
399 fresh_info = true;
400
401 switch (action) {
402 case MPATH_PREQ:
403 orig_addr = PREQ_IE_ORIG_ADDR(hwmp_ie);
404 orig_sn = PREQ_IE_ORIG_SN(hwmp_ie);
405 orig_lifetime = PREQ_IE_LIFETIME(hwmp_ie);
406 orig_metric = PREQ_IE_METRIC(hwmp_ie);
407 break;
408 case MPATH_PREP:
409 /* Originator here refers to the MP that was the target in the
410 * Path Request. We divert from the nomenclature in the draft
411 * so that we can easily use a single function to gather path
412 * information from both PREQ and PREP frames.
413 */
414 orig_addr = PREP_IE_TARGET_ADDR(hwmp_ie);
415 orig_sn = PREP_IE_TARGET_SN(hwmp_ie);
416 orig_lifetime = PREP_IE_LIFETIME(hwmp_ie);
417 orig_metric = PREP_IE_METRIC(hwmp_ie);
418 break;
419 default:
420 rcu_read_unlock();
421 return 0;
422 }
423 new_metric = orig_metric + last_hop_metric;
424 if (new_metric < orig_metric)
425 new_metric = MAX_METRIC;
426 exp_time = TU_TO_EXP_TIME(orig_lifetime);
427
428 if (ether_addr_equal(orig_addr, sdata->vif.addr)) {
429 /* This MP is the originator, we are not interested in this
430 * frame, except for updating transmitter's path info.
431 */
432 process = false;
433 fresh_info = false;
434 } else {
435 mpath = mesh_path_lookup(sdata, orig_addr);
436 if (mpath) {
437 spin_lock_bh(&mpath->state_lock);
438 if (mpath->flags & MESH_PATH_FIXED)
439 fresh_info = false;
440 else if ((mpath->flags & MESH_PATH_ACTIVE) &&
441 (mpath->flags & MESH_PATH_SN_VALID)) {
442 if (SN_GT(mpath->sn, orig_sn) ||
443 (mpath->sn == orig_sn &&
444 new_metric >= mpath->metric)) {
445 process = false;
446 fresh_info = false;
447 }
448 } else if (!(mpath->flags & MESH_PATH_ACTIVE)) {
449 bool have_sn, newer_sn, bounced;
450
451 have_sn = mpath->flags & MESH_PATH_SN_VALID;
452 newer_sn = have_sn && SN_GT(orig_sn, mpath->sn);
453 bounced = have_sn &&
454 (SN_DELTA(orig_sn, mpath->sn) >
455 MAX_SANE_SN_DELTA);
456
457 if (!have_sn || newer_sn) {
458 /* if SN is newer than what we had
459 * then we can take it */;
460 } else if (bounced) {
461 /* if SN is way different than what
462 * we had then assume the other side
463 * rebooted or restarted */;
464 } else {
465 process = false;
466 fresh_info = false;
467 }
468 }
469 } else {
470 mpath = mesh_path_add(sdata, orig_addr);
471 if (IS_ERR(mpath)) {
472 rcu_read_unlock();
473 return 0;
474 }
475 spin_lock_bh(&mpath->state_lock);
476 }
477
478 if (fresh_info) {
479 mesh_path_assign_nexthop(mpath, sta);
480 mpath->flags |= MESH_PATH_SN_VALID;
481 mpath->metric = new_metric;
482 mpath->sn = orig_sn;
483 mpath->exp_time = time_after(mpath->exp_time, exp_time)
484 ? mpath->exp_time : exp_time;
485 mesh_path_activate(mpath);
486 spin_unlock_bh(&mpath->state_lock);
487 ewma_mesh_fail_avg_init(&sta->mesh->fail_avg);
488 /* init it at a low value - 0 start is tricky */
489 ewma_mesh_fail_avg_add(&sta->mesh->fail_avg, 1);
490 mesh_path_tx_pending(mpath);
491 /* draft says preq_id should be saved to, but there does
492 * not seem to be any use for it, skipping by now
493 */
494 } else
495 spin_unlock_bh(&mpath->state_lock);
496 }
497
498 /* Update and check transmitter routing info */
499 ta = mgmt->sa;
500 if (ether_addr_equal(orig_addr, ta))
501 fresh_info = false;
502 else {
503 fresh_info = true;
504
505 mpath = mesh_path_lookup(sdata, ta);
506 if (mpath) {
507 spin_lock_bh(&mpath->state_lock);
508 if ((mpath->flags & MESH_PATH_FIXED) ||
509 ((mpath->flags & MESH_PATH_ACTIVE) &&
510 (last_hop_metric > mpath->metric)))
511 fresh_info = false;
512 } else {
513 mpath = mesh_path_add(sdata, ta);
514 if (IS_ERR(mpath)) {
515 rcu_read_unlock();
516 return 0;
517 }
518 spin_lock_bh(&mpath->state_lock);
519 }
520
521 if (fresh_info) {
522 mesh_path_assign_nexthop(mpath, sta);
523 mpath->metric = last_hop_metric;
524 mpath->exp_time = time_after(mpath->exp_time, exp_time)
525 ? mpath->exp_time : exp_time;
526 mesh_path_activate(mpath);
527 spin_unlock_bh(&mpath->state_lock);
528 ewma_mesh_fail_avg_init(&sta->mesh->fail_avg);
529 /* init it at a low value - 0 start is tricky */
530 ewma_mesh_fail_avg_add(&sta->mesh->fail_avg, 1);
531 mesh_path_tx_pending(mpath);
532 } else
533 spin_unlock_bh(&mpath->state_lock);
534 }
535
536 rcu_read_unlock();
537
538 return process ? new_metric : 0;
539 }
540
541 static void hwmp_preq_frame_process(struct ieee80211_sub_if_data *sdata,
542 struct ieee80211_mgmt *mgmt,
543 const u8 *preq_elem, u32 orig_metric)
544 {
545 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
546 struct mesh_path *mpath = NULL;
547 const u8 *target_addr, *orig_addr;
548 const u8 *da;
549 u8 target_flags, ttl, flags;
550 u32 orig_sn, target_sn, lifetime, target_metric = 0;
551 bool reply = false;
552 bool forward = true;
553 bool root_is_gate;
554
555 /* Update target SN, if present */
556 target_addr = PREQ_IE_TARGET_ADDR(preq_elem);
557 orig_addr = PREQ_IE_ORIG_ADDR(preq_elem);
558 target_sn = PREQ_IE_TARGET_SN(preq_elem);
559 orig_sn = PREQ_IE_ORIG_SN(preq_elem);
560 target_flags = PREQ_IE_TARGET_F(preq_elem);
561 /* Proactive PREQ gate announcements */
562 flags = PREQ_IE_FLAGS(preq_elem);
563 root_is_gate = !!(flags & RANN_FLAG_IS_GATE);
564
565 mhwmp_dbg(sdata, "received PREQ from %pM\n", orig_addr);
566
567 if (ether_addr_equal(target_addr, sdata->vif.addr)) {
568 mhwmp_dbg(sdata, "PREQ is for us\n");
569 forward = false;
570 reply = true;
571 target_metric = 0;
572
573 if (SN_GT(target_sn, ifmsh->sn))
574 ifmsh->sn = target_sn;
575
576 if (time_after(jiffies, ifmsh->last_sn_update +
577 net_traversal_jiffies(sdata)) ||
578 time_before(jiffies, ifmsh->last_sn_update)) {
579 ++ifmsh->sn;
580 ifmsh->last_sn_update = jiffies;
581 }
582 target_sn = ifmsh->sn;
583 } else if (is_broadcast_ether_addr(target_addr) &&
584 (target_flags & IEEE80211_PREQ_TO_FLAG)) {
585 rcu_read_lock();
586 mpath = mesh_path_lookup(sdata, orig_addr);
587 if (mpath) {
588 if (flags & IEEE80211_PREQ_PROACTIVE_PREP_FLAG) {
589 reply = true;
590 target_addr = sdata->vif.addr;
591 target_sn = ++ifmsh->sn;
592 target_metric = 0;
593 ifmsh->last_sn_update = jiffies;
594 }
595 if (root_is_gate)
596 mesh_path_add_gate(mpath);
597 }
598 rcu_read_unlock();
599 } else {
600 rcu_read_lock();
601 mpath = mesh_path_lookup(sdata, target_addr);
602 if (mpath) {
603 if ((!(mpath->flags & MESH_PATH_SN_VALID)) ||
604 SN_LT(mpath->sn, target_sn)) {
605 mpath->sn = target_sn;
606 mpath->flags |= MESH_PATH_SN_VALID;
607 } else if ((!(target_flags & IEEE80211_PREQ_TO_FLAG)) &&
608 (mpath->flags & MESH_PATH_ACTIVE)) {
609 reply = true;
610 target_metric = mpath->metric;
611 target_sn = mpath->sn;
612 /* Case E2 of sec 13.10.9.3 IEEE 802.11-2012*/
613 target_flags |= IEEE80211_PREQ_TO_FLAG;
614 }
615 }
616 rcu_read_unlock();
617 }
618
619 if (reply) {
620 lifetime = PREQ_IE_LIFETIME(preq_elem);
621 ttl = ifmsh->mshcfg.element_ttl;
622 if (ttl != 0) {
623 mhwmp_dbg(sdata, "replying to the PREQ\n");
624 mesh_path_sel_frame_tx(MPATH_PREP, 0, orig_addr,
625 orig_sn, 0, target_addr,
626 target_sn, mgmt->sa, 0, ttl,
627 lifetime, target_metric, 0,
628 sdata);
629 } else {
630 ifmsh->mshstats.dropped_frames_ttl++;
631 }
632 }
633
634 if (forward && ifmsh->mshcfg.dot11MeshForwarding) {
635 u32 preq_id;
636 u8 hopcount;
637
638 ttl = PREQ_IE_TTL(preq_elem);
639 lifetime = PREQ_IE_LIFETIME(preq_elem);
640 if (ttl <= 1) {
641 ifmsh->mshstats.dropped_frames_ttl++;
642 return;
643 }
644 mhwmp_dbg(sdata, "forwarding the PREQ from %pM\n", orig_addr);
645 --ttl;
646 preq_id = PREQ_IE_PREQ_ID(preq_elem);
647 hopcount = PREQ_IE_HOPCOUNT(preq_elem) + 1;
648 da = (mpath && mpath->is_root) ?
649 mpath->rann_snd_addr : broadcast_addr;
650
651 if (flags & IEEE80211_PREQ_PROACTIVE_PREP_FLAG) {
652 target_addr = PREQ_IE_TARGET_ADDR(preq_elem);
653 target_sn = PREQ_IE_TARGET_SN(preq_elem);
654 }
655
656 mesh_path_sel_frame_tx(MPATH_PREQ, flags, orig_addr,
657 orig_sn, target_flags, target_addr,
658 target_sn, da, hopcount, ttl, lifetime,
659 orig_metric, preq_id, sdata);
660 if (!is_multicast_ether_addr(da))
661 ifmsh->mshstats.fwded_unicast++;
662 else
663 ifmsh->mshstats.fwded_mcast++;
664 ifmsh->mshstats.fwded_frames++;
665 }
666 }
667
668
669 static inline struct sta_info *
670 next_hop_deref_protected(struct mesh_path *mpath)
671 {
672 return rcu_dereference_protected(mpath->next_hop,
673 lockdep_is_held(&mpath->state_lock));
674 }
675
676
677 static void hwmp_prep_frame_process(struct ieee80211_sub_if_data *sdata,
678 struct ieee80211_mgmt *mgmt,
679 const u8 *prep_elem, u32 metric)
680 {
681 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
682 struct mesh_path *mpath;
683 const u8 *target_addr, *orig_addr;
684 u8 ttl, hopcount, flags;
685 u8 next_hop[ETH_ALEN];
686 u32 target_sn, orig_sn, lifetime;
687
688 mhwmp_dbg(sdata, "received PREP from %pM\n",
689 PREP_IE_TARGET_ADDR(prep_elem));
690
691 orig_addr = PREP_IE_ORIG_ADDR(prep_elem);
692 if (ether_addr_equal(orig_addr, sdata->vif.addr))
693 /* destination, no forwarding required */
694 return;
695
696 if (!ifmsh->mshcfg.dot11MeshForwarding)
697 return;
698
699 ttl = PREP_IE_TTL(prep_elem);
700 if (ttl <= 1) {
701 sdata->u.mesh.mshstats.dropped_frames_ttl++;
702 return;
703 }
704
705 rcu_read_lock();
706 mpath = mesh_path_lookup(sdata, orig_addr);
707 if (mpath)
708 spin_lock_bh(&mpath->state_lock);
709 else
710 goto fail;
711 if (!(mpath->flags & MESH_PATH_ACTIVE)) {
712 spin_unlock_bh(&mpath->state_lock);
713 goto fail;
714 }
715 memcpy(next_hop, next_hop_deref_protected(mpath)->sta.addr, ETH_ALEN);
716 spin_unlock_bh(&mpath->state_lock);
717 --ttl;
718 flags = PREP_IE_FLAGS(prep_elem);
719 lifetime = PREP_IE_LIFETIME(prep_elem);
720 hopcount = PREP_IE_HOPCOUNT(prep_elem) + 1;
721 target_addr = PREP_IE_TARGET_ADDR(prep_elem);
722 target_sn = PREP_IE_TARGET_SN(prep_elem);
723 orig_sn = PREP_IE_ORIG_SN(prep_elem);
724
725 mesh_path_sel_frame_tx(MPATH_PREP, flags, orig_addr, orig_sn, 0,
726 target_addr, target_sn, next_hop, hopcount,
727 ttl, lifetime, metric, 0, sdata);
728 rcu_read_unlock();
729
730 sdata->u.mesh.mshstats.fwded_unicast++;
731 sdata->u.mesh.mshstats.fwded_frames++;
732 return;
733
734 fail:
735 rcu_read_unlock();
736 sdata->u.mesh.mshstats.dropped_frames_no_route++;
737 }
738
739 static void hwmp_perr_frame_process(struct ieee80211_sub_if_data *sdata,
740 struct ieee80211_mgmt *mgmt,
741 const u8 *perr_elem)
742 {
743 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
744 struct mesh_path *mpath;
745 u8 ttl;
746 const u8 *ta, *target_addr;
747 u32 target_sn;
748 u16 target_rcode;
749
750 ta = mgmt->sa;
751 ttl = PERR_IE_TTL(perr_elem);
752 if (ttl <= 1) {
753 ifmsh->mshstats.dropped_frames_ttl++;
754 return;
755 }
756 ttl--;
757 target_addr = PERR_IE_TARGET_ADDR(perr_elem);
758 target_sn = PERR_IE_TARGET_SN(perr_elem);
759 target_rcode = PERR_IE_TARGET_RCODE(perr_elem);
760
761 rcu_read_lock();
762 mpath = mesh_path_lookup(sdata, target_addr);
763 if (mpath) {
764 struct sta_info *sta;
765
766 spin_lock_bh(&mpath->state_lock);
767 sta = next_hop_deref_protected(mpath);
768 if (mpath->flags & MESH_PATH_ACTIVE &&
769 ether_addr_equal(ta, sta->sta.addr) &&
770 !(mpath->flags & MESH_PATH_FIXED) &&
771 (!(mpath->flags & MESH_PATH_SN_VALID) ||
772 SN_GT(target_sn, mpath->sn) || target_sn == 0)) {
773 mpath->flags &= ~MESH_PATH_ACTIVE;
774 if (target_sn != 0)
775 mpath->sn = target_sn;
776 else
777 mpath->sn += 1;
778 spin_unlock_bh(&mpath->state_lock);
779 if (!ifmsh->mshcfg.dot11MeshForwarding)
780 goto endperr;
781 mesh_path_error_tx(sdata, ttl, target_addr,
782 target_sn, target_rcode,
783 broadcast_addr);
784 } else
785 spin_unlock_bh(&mpath->state_lock);
786 }
787 endperr:
788 rcu_read_unlock();
789 }
790
791 static void hwmp_rann_frame_process(struct ieee80211_sub_if_data *sdata,
792 struct ieee80211_mgmt *mgmt,
793 const struct ieee80211_rann_ie *rann)
794 {
795 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
796 struct ieee80211_local *local = sdata->local;
797 struct sta_info *sta;
798 struct mesh_path *mpath;
799 u8 ttl, flags, hopcount;
800 const u8 *orig_addr;
801 u32 orig_sn, new_metric, orig_metric, last_hop_metric, interval;
802 bool root_is_gate;
803
804 ttl = rann->rann_ttl;
805 flags = rann->rann_flags;
806 root_is_gate = !!(flags & RANN_FLAG_IS_GATE);
807 orig_addr = rann->rann_addr;
808 orig_sn = le32_to_cpu(rann->rann_seq);
809 interval = le32_to_cpu(rann->rann_interval);
810 hopcount = rann->rann_hopcount;
811 hopcount++;
812 orig_metric = le32_to_cpu(rann->rann_metric);
813
814 /* Ignore our own RANNs */
815 if (ether_addr_equal(orig_addr, sdata->vif.addr))
816 return;
817
818 mhwmp_dbg(sdata,
819 "received RANN from %pM via neighbour %pM (is_gate=%d)\n",
820 orig_addr, mgmt->sa, root_is_gate);
821
822 rcu_read_lock();
823 sta = sta_info_get(sdata, mgmt->sa);
824 if (!sta) {
825 rcu_read_unlock();
826 return;
827 }
828
829 last_hop_metric = airtime_link_metric_get(local, sta);
830 new_metric = orig_metric + last_hop_metric;
831 if (new_metric < orig_metric)
832 new_metric = MAX_METRIC;
833
834 mpath = mesh_path_lookup(sdata, orig_addr);
835 if (!mpath) {
836 mpath = mesh_path_add(sdata, orig_addr);
837 if (IS_ERR(mpath)) {
838 rcu_read_unlock();
839 sdata->u.mesh.mshstats.dropped_frames_no_route++;
840 return;
841 }
842 }
843
844 if (!(SN_LT(mpath->sn, orig_sn)) &&
845 !(mpath->sn == orig_sn && new_metric < mpath->rann_metric)) {
846 rcu_read_unlock();
847 return;
848 }
849
850 if ((!(mpath->flags & (MESH_PATH_ACTIVE | MESH_PATH_RESOLVING)) ||
851 (time_after(jiffies, mpath->last_preq_to_root +
852 root_path_confirmation_jiffies(sdata)) ||
853 time_before(jiffies, mpath->last_preq_to_root))) &&
854 !(mpath->flags & MESH_PATH_FIXED) && (ttl != 0)) {
855 mhwmp_dbg(sdata,
856 "time to refresh root mpath %pM\n",
857 orig_addr);
858 mesh_queue_preq(mpath, PREQ_Q_F_START | PREQ_Q_F_REFRESH);
859 mpath->last_preq_to_root = jiffies;
860 }
861
862 mpath->sn = orig_sn;
863 mpath->rann_metric = new_metric;
864 mpath->is_root = true;
865 /* Recording RANNs sender address to send individually
866 * addressed PREQs destined for root mesh STA */
867 memcpy(mpath->rann_snd_addr, mgmt->sa, ETH_ALEN);
868
869 if (root_is_gate)
870 mesh_path_add_gate(mpath);
871
872 if (ttl <= 1) {
873 ifmsh->mshstats.dropped_frames_ttl++;
874 rcu_read_unlock();
875 return;
876 }
877 ttl--;
878
879 if (ifmsh->mshcfg.dot11MeshForwarding) {
880 mesh_path_sel_frame_tx(MPATH_RANN, flags, orig_addr,
881 orig_sn, 0, NULL, 0, broadcast_addr,
882 hopcount, ttl, interval,
883 new_metric, 0, sdata);
884 }
885
886 rcu_read_unlock();
887 }
888
889
890 void mesh_rx_path_sel_frame(struct ieee80211_sub_if_data *sdata,
891 struct ieee80211_mgmt *mgmt, size_t len)
892 {
893 struct ieee802_11_elems elems;
894 size_t baselen;
895 u32 path_metric;
896 struct sta_info *sta;
897
898 /* need action_code */
899 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
900 return;
901
902 rcu_read_lock();
903 sta = sta_info_get(sdata, mgmt->sa);
904 if (!sta || sta->mesh->plink_state != NL80211_PLINK_ESTAB) {
905 rcu_read_unlock();
906 return;
907 }
908 rcu_read_unlock();
909
910 baselen = (u8 *) mgmt->u.action.u.mesh_action.variable - (u8 *) mgmt;
911 ieee802_11_parse_elems(mgmt->u.action.u.mesh_action.variable,
912 len - baselen, false, &elems);
913
914 if (elems.preq) {
915 if (elems.preq_len != 37)
916 /* Right now we support just 1 destination and no AE */
917 return;
918 path_metric = hwmp_route_info_get(sdata, mgmt, elems.preq,
919 MPATH_PREQ);
920 if (path_metric)
921 hwmp_preq_frame_process(sdata, mgmt, elems.preq,
922 path_metric);
923 }
924 if (elems.prep) {
925 if (elems.prep_len != 31)
926 /* Right now we support no AE */
927 return;
928 path_metric = hwmp_route_info_get(sdata, mgmt, elems.prep,
929 MPATH_PREP);
930 if (path_metric)
931 hwmp_prep_frame_process(sdata, mgmt, elems.prep,
932 path_metric);
933 }
934 if (elems.perr) {
935 if (elems.perr_len != 15)
936 /* Right now we support only one destination per PERR */
937 return;
938 hwmp_perr_frame_process(sdata, mgmt, elems.perr);
939 }
940 if (elems.rann)
941 hwmp_rann_frame_process(sdata, mgmt, elems.rann);
942 }
943
944 /**
945 * mesh_queue_preq - queue a PREQ to a given destination
946 *
947 * @mpath: mesh path to discover
948 * @flags: special attributes of the PREQ to be sent
949 *
950 * Locking: the function must be called from within a rcu read lock block.
951 *
952 */
953 static void mesh_queue_preq(struct mesh_path *mpath, u8 flags)
954 {
955 struct ieee80211_sub_if_data *sdata = mpath->sdata;
956 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
957 struct mesh_preq_queue *preq_node;
958
959 preq_node = kmalloc(sizeof(struct mesh_preq_queue), GFP_ATOMIC);
960 if (!preq_node) {
961 mhwmp_dbg(sdata, "could not allocate PREQ node\n");
962 return;
963 }
964
965 spin_lock_bh(&ifmsh->mesh_preq_queue_lock);
966 if (ifmsh->preq_queue_len == MAX_PREQ_QUEUE_LEN) {
967 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
968 kfree(preq_node);
969 if (printk_ratelimit())
970 mhwmp_dbg(sdata, "PREQ node queue full\n");
971 return;
972 }
973
974 spin_lock(&mpath->state_lock);
975 if (mpath->flags & MESH_PATH_REQ_QUEUED) {
976 spin_unlock(&mpath->state_lock);
977 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
978 kfree(preq_node);
979 return;
980 }
981
982 memcpy(preq_node->dst, mpath->dst, ETH_ALEN);
983 preq_node->flags = flags;
984
985 mpath->flags |= MESH_PATH_REQ_QUEUED;
986 spin_unlock(&mpath->state_lock);
987
988 list_add_tail(&preq_node->list, &ifmsh->preq_queue.list);
989 ++ifmsh->preq_queue_len;
990 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
991
992 if (time_after(jiffies, ifmsh->last_preq + min_preq_int_jiff(sdata)))
993 ieee80211_queue_work(&sdata->local->hw, &sdata->work);
994
995 else if (time_before(jiffies, ifmsh->last_preq)) {
996 /* avoid long wait if did not send preqs for a long time
997 * and jiffies wrapped around
998 */
999 ifmsh->last_preq = jiffies - min_preq_int_jiff(sdata) - 1;
1000 ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1001 } else
1002 mod_timer(&ifmsh->mesh_path_timer, ifmsh->last_preq +
1003 min_preq_int_jiff(sdata));
1004 }
1005
1006 /**
1007 * mesh_path_start_discovery - launch a path discovery from the PREQ queue
1008 *
1009 * @sdata: local mesh subif
1010 */
1011 void mesh_path_start_discovery(struct ieee80211_sub_if_data *sdata)
1012 {
1013 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1014 struct mesh_preq_queue *preq_node;
1015 struct mesh_path *mpath;
1016 u8 ttl, target_flags = 0;
1017 const u8 *da;
1018 u32 lifetime;
1019
1020 spin_lock_bh(&ifmsh->mesh_preq_queue_lock);
1021 if (!ifmsh->preq_queue_len ||
1022 time_before(jiffies, ifmsh->last_preq +
1023 min_preq_int_jiff(sdata))) {
1024 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
1025 return;
1026 }
1027
1028 preq_node = list_first_entry(&ifmsh->preq_queue.list,
1029 struct mesh_preq_queue, list);
1030 list_del(&preq_node->list);
1031 --ifmsh->preq_queue_len;
1032 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
1033
1034 rcu_read_lock();
1035 mpath = mesh_path_lookup(sdata, preq_node->dst);
1036 if (!mpath)
1037 goto enddiscovery;
1038
1039 spin_lock_bh(&mpath->state_lock);
1040 if (mpath->flags & (MESH_PATH_DELETED | MESH_PATH_FIXED)) {
1041 spin_unlock_bh(&mpath->state_lock);
1042 goto enddiscovery;
1043 }
1044 mpath->flags &= ~MESH_PATH_REQ_QUEUED;
1045 if (preq_node->flags & PREQ_Q_F_START) {
1046 if (mpath->flags & MESH_PATH_RESOLVING) {
1047 spin_unlock_bh(&mpath->state_lock);
1048 goto enddiscovery;
1049 } else {
1050 mpath->flags &= ~MESH_PATH_RESOLVED;
1051 mpath->flags |= MESH_PATH_RESOLVING;
1052 mpath->discovery_retries = 0;
1053 mpath->discovery_timeout = disc_timeout_jiff(sdata);
1054 }
1055 } else if (!(mpath->flags & MESH_PATH_RESOLVING) ||
1056 mpath->flags & MESH_PATH_RESOLVED) {
1057 mpath->flags &= ~MESH_PATH_RESOLVING;
1058 spin_unlock_bh(&mpath->state_lock);
1059 goto enddiscovery;
1060 }
1061
1062 ifmsh->last_preq = jiffies;
1063
1064 if (time_after(jiffies, ifmsh->last_sn_update +
1065 net_traversal_jiffies(sdata)) ||
1066 time_before(jiffies, ifmsh->last_sn_update)) {
1067 ++ifmsh->sn;
1068 sdata->u.mesh.last_sn_update = jiffies;
1069 }
1070 lifetime = default_lifetime(sdata);
1071 ttl = sdata->u.mesh.mshcfg.element_ttl;
1072 if (ttl == 0) {
1073 sdata->u.mesh.mshstats.dropped_frames_ttl++;
1074 spin_unlock_bh(&mpath->state_lock);
1075 goto enddiscovery;
1076 }
1077
1078 if (preq_node->flags & PREQ_Q_F_REFRESH)
1079 target_flags |= IEEE80211_PREQ_TO_FLAG;
1080 else
1081 target_flags &= ~IEEE80211_PREQ_TO_FLAG;
1082
1083 spin_unlock_bh(&mpath->state_lock);
1084 da = (mpath->is_root) ? mpath->rann_snd_addr : broadcast_addr;
1085 mesh_path_sel_frame_tx(MPATH_PREQ, 0, sdata->vif.addr, ifmsh->sn,
1086 target_flags, mpath->dst, mpath->sn, da, 0,
1087 ttl, lifetime, 0, ifmsh->preq_id++, sdata);
1088 mod_timer(&mpath->timer, jiffies + mpath->discovery_timeout);
1089
1090 enddiscovery:
1091 rcu_read_unlock();
1092 kfree(preq_node);
1093 }
1094
1095 /**
1096 * mesh_nexthop_resolve - lookup next hop; conditionally start path discovery
1097 *
1098 * @skb: 802.11 frame to be sent
1099 * @sdata: network subif the frame will be sent through
1100 *
1101 * Lookup next hop for given skb and start path discovery if no
1102 * forwarding information is found.
1103 *
1104 * Returns: 0 if the next hop was found and -ENOENT if the frame was queued.
1105 * skb is freeed here if no mpath could be allocated.
1106 */
1107 int mesh_nexthop_resolve(struct ieee80211_sub_if_data *sdata,
1108 struct sk_buff *skb)
1109 {
1110 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1111 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1112 struct mesh_path *mpath;
1113 struct sk_buff *skb_to_free = NULL;
1114 u8 *target_addr = hdr->addr3;
1115 int err = 0;
1116
1117 /* Nulls are only sent to peers for PS and should be pre-addressed */
1118 if (ieee80211_is_qos_nullfunc(hdr->frame_control))
1119 return 0;
1120
1121 rcu_read_lock();
1122 err = mesh_nexthop_lookup(sdata, skb);
1123 if (!err)
1124 goto endlookup;
1125
1126 /* no nexthop found, start resolving */
1127 mpath = mesh_path_lookup(sdata, target_addr);
1128 if (!mpath) {
1129 mpath = mesh_path_add(sdata, target_addr);
1130 if (IS_ERR(mpath)) {
1131 mesh_path_discard_frame(sdata, skb);
1132 err = PTR_ERR(mpath);
1133 goto endlookup;
1134 }
1135 }
1136
1137 if (!(mpath->flags & MESH_PATH_RESOLVING))
1138 mesh_queue_preq(mpath, PREQ_Q_F_START);
1139
1140 if (skb_queue_len(&mpath->frame_queue) >= MESH_FRAME_QUEUE_LEN)
1141 skb_to_free = skb_dequeue(&mpath->frame_queue);
1142
1143 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1144 ieee80211_set_qos_hdr(sdata, skb);
1145 skb_queue_tail(&mpath->frame_queue, skb);
1146 err = -ENOENT;
1147 if (skb_to_free)
1148 mesh_path_discard_frame(sdata, skb_to_free);
1149
1150 endlookup:
1151 rcu_read_unlock();
1152 return err;
1153 }
1154
1155 /**
1156 * mesh_nexthop_lookup - put the appropriate next hop on a mesh frame. Calling
1157 * this function is considered "using" the associated mpath, so preempt a path
1158 * refresh if this mpath expires soon.
1159 *
1160 * @skb: 802.11 frame to be sent
1161 * @sdata: network subif the frame will be sent through
1162 *
1163 * Returns: 0 if the next hop was found. Nonzero otherwise.
1164 */
1165 int mesh_nexthop_lookup(struct ieee80211_sub_if_data *sdata,
1166 struct sk_buff *skb)
1167 {
1168 struct mesh_path *mpath;
1169 struct sta_info *next_hop;
1170 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1171 u8 *target_addr = hdr->addr3;
1172 int err = -ENOENT;
1173
1174 rcu_read_lock();
1175 mpath = mesh_path_lookup(sdata, target_addr);
1176
1177 if (!mpath || !(mpath->flags & MESH_PATH_ACTIVE))
1178 goto endlookup;
1179
1180 if (time_after(jiffies,
1181 mpath->exp_time -
1182 msecs_to_jiffies(sdata->u.mesh.mshcfg.path_refresh_time)) &&
1183 ether_addr_equal(sdata->vif.addr, hdr->addr4) &&
1184 !(mpath->flags & MESH_PATH_RESOLVING) &&
1185 !(mpath->flags & MESH_PATH_FIXED))
1186 mesh_queue_preq(mpath, PREQ_Q_F_START | PREQ_Q_F_REFRESH);
1187
1188 next_hop = rcu_dereference(mpath->next_hop);
1189 if (next_hop) {
1190 memcpy(hdr->addr1, next_hop->sta.addr, ETH_ALEN);
1191 memcpy(hdr->addr2, sdata->vif.addr, ETH_ALEN);
1192 ieee80211_mps_set_frame_flags(sdata, next_hop, hdr);
1193 err = 0;
1194 }
1195
1196 endlookup:
1197 rcu_read_unlock();
1198 return err;
1199 }
1200
1201 void mesh_path_timer(struct timer_list *t)
1202 {
1203 struct mesh_path *mpath = from_timer(mpath, t, timer);
1204 struct ieee80211_sub_if_data *sdata = mpath->sdata;
1205 int ret;
1206
1207 if (sdata->local->quiescing)
1208 return;
1209
1210 spin_lock_bh(&mpath->state_lock);
1211 if (mpath->flags & MESH_PATH_RESOLVED ||
1212 (!(mpath->flags & MESH_PATH_RESOLVING))) {
1213 mpath->flags &= ~(MESH_PATH_RESOLVING | MESH_PATH_RESOLVED);
1214 spin_unlock_bh(&mpath->state_lock);
1215 } else if (mpath->discovery_retries < max_preq_retries(sdata)) {
1216 ++mpath->discovery_retries;
1217 mpath->discovery_timeout *= 2;
1218 mpath->flags &= ~MESH_PATH_REQ_QUEUED;
1219 spin_unlock_bh(&mpath->state_lock);
1220 mesh_queue_preq(mpath, 0);
1221 } else {
1222 mpath->flags &= ~(MESH_PATH_RESOLVING |
1223 MESH_PATH_RESOLVED |
1224 MESH_PATH_REQ_QUEUED);
1225 mpath->exp_time = jiffies;
1226 spin_unlock_bh(&mpath->state_lock);
1227 if (!mpath->is_gate && mesh_gate_num(sdata) > 0) {
1228 ret = mesh_path_send_to_gates(mpath);
1229 if (ret)
1230 mhwmp_dbg(sdata, "no gate was reachable\n");
1231 } else
1232 mesh_path_flush_pending(mpath);
1233 }
1234 }
1235
1236 void mesh_path_tx_root_frame(struct ieee80211_sub_if_data *sdata)
1237 {
1238 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1239 u32 interval = ifmsh->mshcfg.dot11MeshHWMPRannInterval;
1240 u8 flags, target_flags = 0;
1241
1242 flags = (ifmsh->mshcfg.dot11MeshGateAnnouncementProtocol)
1243 ? RANN_FLAG_IS_GATE : 0;
1244
1245 switch (ifmsh->mshcfg.dot11MeshHWMPRootMode) {
1246 case IEEE80211_PROACTIVE_RANN:
1247 mesh_path_sel_frame_tx(MPATH_RANN, flags, sdata->vif.addr,
1248 ++ifmsh->sn, 0, NULL, 0, broadcast_addr,
1249 0, ifmsh->mshcfg.element_ttl,
1250 interval, 0, 0, sdata);
1251 break;
1252 case IEEE80211_PROACTIVE_PREQ_WITH_PREP:
1253 flags |= IEEE80211_PREQ_PROACTIVE_PREP_FLAG;
1254 /* fall through */
1255 case IEEE80211_PROACTIVE_PREQ_NO_PREP:
1256 interval = ifmsh->mshcfg.dot11MeshHWMPactivePathToRootTimeout;
1257 target_flags |= IEEE80211_PREQ_TO_FLAG |
1258 IEEE80211_PREQ_USN_FLAG;
1259 mesh_path_sel_frame_tx(MPATH_PREQ, flags, sdata->vif.addr,
1260 ++ifmsh->sn, target_flags,
1261 (u8 *) broadcast_addr, 0, broadcast_addr,
1262 0, ifmsh->mshcfg.element_ttl, interval,
1263 0, ifmsh->preq_id++, sdata);
1264 break;
1265 default:
1266 mhwmp_dbg(sdata, "Proactive mechanism not supported\n");
1267 return;
1268 }
1269 }
Linux with added FPC-III support