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ARM: mmp: fix potential NULL dereference
[linux/fpc-iii.git] / net / mac80211 / mesh_hwmp.c
blob494bc39f61a4cb67fce07ad649e9be814fcb9d6b
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
20 /* Number of frames buffered per destination for unresolved destinations */
21 #define MESH_FRAME_QUEUE_LEN 10
22 #define MAX_PREQ_QUEUE_LEN 64
23
24 /* Destination only */
25 #define MP_F_DO 0x1
26 /* Reply and forward */
27 #define MP_F_RF 0x2
28 /* Unknown Sequence Number */
29 #define MP_F_USN 0x01
30 /* Reason code Present */
31 #define MP_F_RCODE 0x02
32
33 static void mesh_queue_preq(struct mesh_path *, u8);
34
35 static inline u32 u32_field_get(u8 *preq_elem, int offset, bool ae)
36 {
37 if (ae)
38 offset += 6;
39 return get_unaligned_le32(preq_elem + offset);
40 }
41
42 static inline u32 u16_field_get(u8 *preq_elem, int offset, bool ae)
43 {
44 if (ae)
45 offset += 6;
46 return get_unaligned_le16(preq_elem + offset);
47 }
48
49 /* HWMP IE processing macros */
50 #define AE_F (1<<6)
51 #define AE_F_SET(x) (*x & AE_F)
52 #define PREQ_IE_FLAGS(x) (*(x))
53 #define PREQ_IE_HOPCOUNT(x) (*(x + 1))
54 #define PREQ_IE_TTL(x) (*(x + 2))
55 #define PREQ_IE_PREQ_ID(x) u32_field_get(x, 3, 0)
56 #define PREQ_IE_ORIG_ADDR(x) (x + 7)
57 #define PREQ_IE_ORIG_SN(x) u32_field_get(x, 13, 0)
58 #define PREQ_IE_LIFETIME(x) u32_field_get(x, 17, AE_F_SET(x))
59 #define PREQ_IE_METRIC(x) u32_field_get(x, 21, AE_F_SET(x))
60 #define PREQ_IE_TARGET_F(x) (*(AE_F_SET(x) ? x + 32 : x + 26))
61 #define PREQ_IE_TARGET_ADDR(x) (AE_F_SET(x) ? x + 33 : x + 27)
62 #define PREQ_IE_TARGET_SN(x) u32_field_get(x, 33, AE_F_SET(x))
63
64
65 #define PREP_IE_FLAGS(x) PREQ_IE_FLAGS(x)
66 #define PREP_IE_HOPCOUNT(x) PREQ_IE_HOPCOUNT(x)
67 #define PREP_IE_TTL(x) PREQ_IE_TTL(x)
68 #define PREP_IE_ORIG_ADDR(x) (AE_F_SET(x) ? x + 27 : x + 21)
69 #define PREP_IE_ORIG_SN(x) u32_field_get(x, 27, AE_F_SET(x))
70 #define PREP_IE_LIFETIME(x) u32_field_get(x, 13, AE_F_SET(x))
71 #define PREP_IE_METRIC(x) u32_field_get(x, 17, AE_F_SET(x))
72 #define PREP_IE_TARGET_ADDR(x) (x + 3)
73 #define PREP_IE_TARGET_SN(x) u32_field_get(x, 9, 0)
74
75 #define PERR_IE_TTL(x) (*(x))
76 #define PERR_IE_TARGET_FLAGS(x) (*(x + 2))
77 #define PERR_IE_TARGET_ADDR(x) (x + 3)
78 #define PERR_IE_TARGET_SN(x) u32_field_get(x, 9, 0)
79 #define PERR_IE_TARGET_RCODE(x) u16_field_get(x, 13, 0)
80
81 #define MSEC_TO_TU(x) (x*1000/1024)
82 #define SN_GT(x, y) ((s32)(y - x) < 0)
83 #define SN_LT(x, y) ((s32)(x - y) < 0)
84
85 #define net_traversal_jiffies(s) \
86 msecs_to_jiffies(s->u.mesh.mshcfg.dot11MeshHWMPnetDiameterTraversalTime)
87 #define default_lifetime(s) \
88 MSEC_TO_TU(s->u.mesh.mshcfg.dot11MeshHWMPactivePathTimeout)
89 #define min_preq_int_jiff(s) \
90 (msecs_to_jiffies(s->u.mesh.mshcfg.dot11MeshHWMPpreqMinInterval))
91 #define max_preq_retries(s) (s->u.mesh.mshcfg.dot11MeshHWMPmaxPREQretries)
92 #define disc_timeout_jiff(s) \
93 msecs_to_jiffies(sdata->u.mesh.mshcfg.min_discovery_timeout)
94 #define root_path_confirmation_jiffies(s) \
95 msecs_to_jiffies(sdata->u.mesh.mshcfg.dot11MeshHWMPconfirmationInterval)
96
97 enum mpath_frame_type {
98 MPATH_PREQ = 0,
99 MPATH_PREP,
100 MPATH_PERR,
101 MPATH_RANN
102 };
103
104 static const u8 broadcast_addr[ETH_ALEN] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
105
106 static int mesh_path_sel_frame_tx(enum mpath_frame_type action, u8 flags,
107 u8 *orig_addr, __le32 orig_sn, u8 target_flags, u8 *target,
108 __le32 target_sn, const u8 *da, u8 hop_count, u8 ttl,
109 __le32 lifetime, __le32 metric, __le32 preq_id,
110 struct ieee80211_sub_if_data *sdata)
111 {
112 struct ieee80211_local *local = sdata->local;
113 struct sk_buff *skb;
114 struct ieee80211_mgmt *mgmt;
115 u8 *pos, ie_len;
116 int hdr_len = offsetof(struct ieee80211_mgmt, u.action.u.mesh_action) +
117 sizeof(mgmt->u.action.u.mesh_action);
118
119 skb = dev_alloc_skb(local->tx_headroom +
120 hdr_len +
121 2 + 37); /* max HWMP IE */
122 if (!skb)
123 return -1;
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);
129
130 memcpy(mgmt->da, da, ETH_ALEN);
131 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
132 /* BSSID == SA */
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;
137
138 switch (action) {
139 case MPATH_PREQ:
140 mhwmp_dbg(sdata, "sending PREQ to %pM\n", target);
141 ie_len = 37;
142 pos = skb_put(skb, 2 + ie_len);
143 *pos++ = WLAN_EID_PREQ;
144 break;
145 case MPATH_PREP:
146 mhwmp_dbg(sdata, "sending PREP to %pM\n", target);
147 ie_len = 31;
148 pos = skb_put(skb, 2 + ie_len);
149 *pos++ = WLAN_EID_PREP;
150 break;
151 case MPATH_RANN:
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;
156 break;
157 default:
158 kfree_skb(skb);
159 return -ENOTSUPP;
160 break;
161 }
162 *pos++ = ie_len;
163 *pos++ = flags;
164 *pos++ = hop_count;
165 *pos++ = ttl;
166 if (action == MPATH_PREP) {
167 memcpy(pos, target, ETH_ALEN);
168 pos += ETH_ALEN;
169 memcpy(pos, &target_sn, 4);
170 pos += 4;
171 } else {
172 if (action == MPATH_PREQ) {
173 memcpy(pos, &preq_id, 4);
174 pos += 4;
175 }
176 memcpy(pos, orig_addr, ETH_ALEN);
177 pos += ETH_ALEN;
178 memcpy(pos, &orig_sn, 4);
179 pos += 4;
180 }
181 memcpy(pos, &lifetime, 4); /* interval for RANN */
182 pos += 4;
183 memcpy(pos, &metric, 4);
184 pos += 4;
185 if (action == MPATH_PREQ) {
186 *pos++ = 1; /* destination count */
187 *pos++ = target_flags;
188 memcpy(pos, target, ETH_ALEN);
189 pos += ETH_ALEN;
190 memcpy(pos, &target_sn, 4);
191 pos += 4;
192 } else if (action == MPATH_PREP) {
193 memcpy(pos, orig_addr, ETH_ALEN);
194 pos += ETH_ALEN;
195 memcpy(pos, &orig_sn, 4);
196 pos += 4;
197 }
198
199 ieee80211_tx_skb(sdata, skb);
200 return 0;
201 }
202
203
204 /* Headroom is not adjusted. Caller should ensure that skb has sufficient
205 * headroom in case the frame is encrypted. */
206 static void prepare_frame_for_deferred_tx(struct ieee80211_sub_if_data *sdata,
207 struct sk_buff *skb)
208 {
209 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
210
211 skb_set_mac_header(skb, 0);
212 skb_set_network_header(skb, 0);
213 skb_set_transport_header(skb, 0);
214
215 /* Send all internal mgmt frames on VO. Accordingly set TID to 7. */
216 skb_set_queue_mapping(skb, IEEE80211_AC_VO);
217 skb->priority = 7;
218
219 info->control.vif = &sdata->vif;
220 ieee80211_set_qos_hdr(sdata, skb);
221 }
222
223 /**
224 * mesh_send_path error - Sends a PERR mesh management frame
225 *
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 *
231 * Note: This function may be called with driver locks taken that the driver
232 * also acquires in the TX path. To avoid a deadlock we don't transmit the
233 * frame directly but add it to the pending queue instead.
234 */
235 int mesh_path_error_tx(u8 ttl, u8 *target, __le32 target_sn,
236 __le16 target_rcode, const u8 *ra,
237 struct ieee80211_sub_if_data *sdata)
238 {
239 struct ieee80211_local *local = sdata->local;
240 struct sk_buff *skb;
241 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
242 struct ieee80211_mgmt *mgmt;
243 u8 *pos, ie_len;
244 int hdr_len = offsetof(struct ieee80211_mgmt, u.action.u.mesh_action) +
245 sizeof(mgmt->u.action.u.mesh_action);
246
247 if (time_before(jiffies, ifmsh->next_perr))
248 return -EAGAIN;
249
250 skb = dev_alloc_skb(local->tx_headroom +
251 hdr_len +
252 2 + 15 /* PERR IE */);
253 if (!skb)
254 return -1;
255 skb_reserve(skb, local->tx_headroom);
256 mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len);
257 memset(mgmt, 0, hdr_len);
258 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
259 IEEE80211_STYPE_ACTION);
260
261 memcpy(mgmt->da, ra, ETH_ALEN);
262 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
263 /* BSSID == SA */
264 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
265 mgmt->u.action.category = WLAN_CATEGORY_MESH_ACTION;
266 mgmt->u.action.u.mesh_action.action_code =
267 WLAN_MESH_ACTION_HWMP_PATH_SELECTION;
268 ie_len = 15;
269 pos = skb_put(skb, 2 + ie_len);
270 *pos++ = WLAN_EID_PERR;
271 *pos++ = ie_len;
272 /* ttl */
273 *pos++ = ttl;
274 /* number of destinations */
275 *pos++ = 1;
276 /*
277 * flags bit, bit 1 is unset if we know the sequence number and
278 * bit 2 is set if we have a reason code
279 */
280 *pos = 0;
281 if (!target_sn)
282 *pos |= MP_F_USN;
283 if (target_rcode)
284 *pos |= MP_F_RCODE;
285 pos++;
286 memcpy(pos, target, ETH_ALEN);
287 pos += ETH_ALEN;
288 memcpy(pos, &target_sn, 4);
289 pos += 4;
290 memcpy(pos, &target_rcode, 2);
291
292 /* see note in function header */
293 prepare_frame_for_deferred_tx(sdata, skb);
294 ifmsh->next_perr = TU_TO_EXP_TIME(
295 ifmsh->mshcfg.dot11MeshHWMPperrMinInterval);
296 ieee80211_add_pending_skb(local, skb);
297 return 0;
298 }
299
300 void ieee80211s_update_metric(struct ieee80211_local *local,
301 struct sta_info *sta, struct sk_buff *skb)
302 {
303 struct ieee80211_tx_info *txinfo = IEEE80211_SKB_CB(skb);
304 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
305 int failed;
306
307 if (!ieee80211_is_data(hdr->frame_control))
308 return;
309
310 failed = !(txinfo->flags & IEEE80211_TX_STAT_ACK);
311
312 /* moving average, scaled to 100 */
313 sta->fail_avg = ((80 * sta->fail_avg + 5) / 100 + 20 * failed);
314 if (sta->fail_avg > 95)
315 mesh_plink_broken(sta);
316 }
317
318 static u32 airtime_link_metric_get(struct ieee80211_local *local,
319 struct sta_info *sta)
320 {
321 struct rate_info rinfo;
322 /* This should be adjusted for each device */
323 int device_constant = 1 << ARITH_SHIFT;
324 int test_frame_len = TEST_FRAME_LEN << ARITH_SHIFT;
325 int s_unit = 1 << ARITH_SHIFT;
326 int rate, err;
327 u32 tx_time, estimated_retx;
328 u64 result;
329
330 if (sta->fail_avg >= 100)
331 return MAX_METRIC;
332
333 sta_set_rate_info_tx(sta, &sta->last_tx_rate, &rinfo);
334 rate = cfg80211_calculate_bitrate(&rinfo);
335 if (WARN_ON(!rate))
336 return MAX_METRIC;
337
338 err = (sta->fail_avg << ARITH_SHIFT) / 100;
339
340 /* bitrate is in units of 100 Kbps, while we need rate in units of
341 * 1Mbps. This will be corrected on tx_time computation.
342 */
343 tx_time = (device_constant + 10 * test_frame_len / rate);
344 estimated_retx = ((1 << (2 * ARITH_SHIFT)) / (s_unit - err));
345 result = (tx_time * estimated_retx) >> (2 * ARITH_SHIFT) ;
346 return (u32)result;
347 }
348
349 /**
350 * hwmp_route_info_get - Update routing info to originator and transmitter
351 *
352 * @sdata: local mesh subif
353 * @mgmt: mesh management frame
354 * @hwmp_ie: hwmp information element (PREP or PREQ)
355 *
356 * This function updates the path routing information to the originator and the
357 * transmitter of a HWMP PREQ or PREP frame.
358 *
359 * Returns: metric to frame originator or 0 if the frame should not be further
360 * processed
361 *
362 * Notes: this function is the only place (besides user-provided info) where
363 * path routing information is updated.
364 */
365 static u32 hwmp_route_info_get(struct ieee80211_sub_if_data *sdata,
366 struct ieee80211_mgmt *mgmt,
367 u8 *hwmp_ie, enum mpath_frame_type action)
368 {
369 struct ieee80211_local *local = sdata->local;
370 struct mesh_path *mpath;
371 struct sta_info *sta;
372 bool fresh_info;
373 u8 *orig_addr, *ta;
374 u32 orig_sn, orig_metric;
375 unsigned long orig_lifetime, exp_time;
376 u32 last_hop_metric, new_metric;
377 bool process = true;
378
379 rcu_read_lock();
380 sta = sta_info_get(sdata, mgmt->sa);
381 if (!sta) {
382 rcu_read_unlock();
383 return 0;
384 }
385
386 last_hop_metric = airtime_link_metric_get(local, sta);
387 /* Update and check originator routing info */
388 fresh_info = true;
389
390 switch (action) {
391 case MPATH_PREQ:
392 orig_addr = PREQ_IE_ORIG_ADDR(hwmp_ie);
393 orig_sn = PREQ_IE_ORIG_SN(hwmp_ie);
394 orig_lifetime = PREQ_IE_LIFETIME(hwmp_ie);
395 orig_metric = PREQ_IE_METRIC(hwmp_ie);
396 break;
397 case MPATH_PREP:
398 /* Originator here refers to the MP that was the target in the
399 * Path Request. We divert from the nomenclature in the draft
400 * so that we can easily use a single function to gather path
401 * information from both PREQ and PREP frames.
402 */
403 orig_addr = PREP_IE_TARGET_ADDR(hwmp_ie);
404 orig_sn = PREP_IE_TARGET_SN(hwmp_ie);
405 orig_lifetime = PREP_IE_LIFETIME(hwmp_ie);
406 orig_metric = PREP_IE_METRIC(hwmp_ie);
407 break;
408 default:
409 rcu_read_unlock();
410 return 0;
411 }
412 new_metric = orig_metric + last_hop_metric;
413 if (new_metric < orig_metric)
414 new_metric = MAX_METRIC;
415 exp_time = TU_TO_EXP_TIME(orig_lifetime);
416
417 if (ether_addr_equal(orig_addr, sdata->vif.addr)) {
418 /* This MP is the originator, we are not interested in this
419 * frame, except for updating transmitter's path info.
420 */
421 process = false;
422 fresh_info = false;
423 } else {
424 mpath = mesh_path_lookup(orig_addr, sdata);
425 if (mpath) {
426 spin_lock_bh(&mpath->state_lock);
427 if (mpath->flags & MESH_PATH_FIXED)
428 fresh_info = false;
429 else if ((mpath->flags & MESH_PATH_ACTIVE) &&
430 (mpath->flags & MESH_PATH_SN_VALID)) {
431 if (SN_GT(mpath->sn, orig_sn) ||
432 (mpath->sn == orig_sn &&
433 new_metric >= mpath->metric)) {
434 process = false;
435 fresh_info = false;
436 }
437 }
438 } else {
439 mesh_path_add(orig_addr, sdata);
440 mpath = mesh_path_lookup(orig_addr, sdata);
441 if (!mpath) {
442 rcu_read_unlock();
443 return 0;
444 }
445 spin_lock_bh(&mpath->state_lock);
446 }
447
448 if (fresh_info) {
449 mesh_path_assign_nexthop(mpath, sta);
450 mpath->flags |= MESH_PATH_SN_VALID;
451 mpath->metric = new_metric;
452 mpath->sn = orig_sn;
453 mpath->exp_time = time_after(mpath->exp_time, exp_time)
454 ? mpath->exp_time : exp_time;
455 mesh_path_activate(mpath);
456 spin_unlock_bh(&mpath->state_lock);
457 mesh_path_tx_pending(mpath);
458 /* draft says preq_id should be saved to, but there does
459 * not seem to be any use for it, skipping by now
460 */
461 } else
462 spin_unlock_bh(&mpath->state_lock);
463 }
464
465 /* Update and check transmitter routing info */
466 ta = mgmt->sa;
467 if (ether_addr_equal(orig_addr, ta))
468 fresh_info = false;
469 else {
470 fresh_info = true;
471
472 mpath = mesh_path_lookup(ta, sdata);
473 if (mpath) {
474 spin_lock_bh(&mpath->state_lock);
475 if ((mpath->flags & MESH_PATH_FIXED) ||
476 ((mpath->flags & MESH_PATH_ACTIVE) &&
477 (last_hop_metric > mpath->metric)))
478 fresh_info = false;
479 } else {
480 mesh_path_add(ta, sdata);
481 mpath = mesh_path_lookup(ta, sdata);
482 if (!mpath) {
483 rcu_read_unlock();
484 return 0;
485 }
486 spin_lock_bh(&mpath->state_lock);
487 }
488
489 if (fresh_info) {
490 mesh_path_assign_nexthop(mpath, sta);
491 mpath->metric = last_hop_metric;
492 mpath->exp_time = time_after(mpath->exp_time, exp_time)
493 ? mpath->exp_time : exp_time;
494 mesh_path_activate(mpath);
495 spin_unlock_bh(&mpath->state_lock);
496 mesh_path_tx_pending(mpath);
497 } else
498 spin_unlock_bh(&mpath->state_lock);
499 }
500
501 rcu_read_unlock();
502
503 return process ? new_metric : 0;
504 }
505
506 static void hwmp_preq_frame_process(struct ieee80211_sub_if_data *sdata,
507 struct ieee80211_mgmt *mgmt,
508 u8 *preq_elem, u32 metric)
509 {
510 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
511 struct mesh_path *mpath = NULL;
512 u8 *target_addr, *orig_addr;
513 const u8 *da;
514 u8 target_flags, ttl, flags;
515 u32 orig_sn, target_sn, lifetime, orig_metric;
516 bool reply = false;
517 bool forward = true;
518 bool root_is_gate;
519
520 /* Update target SN, if present */
521 target_addr = PREQ_IE_TARGET_ADDR(preq_elem);
522 orig_addr = PREQ_IE_ORIG_ADDR(preq_elem);
523 target_sn = PREQ_IE_TARGET_SN(preq_elem);
524 orig_sn = PREQ_IE_ORIG_SN(preq_elem);
525 target_flags = PREQ_IE_TARGET_F(preq_elem);
526 orig_metric = metric;
527 /* Proactive PREQ gate announcements */
528 flags = PREQ_IE_FLAGS(preq_elem);
529 root_is_gate = !!(flags & RANN_FLAG_IS_GATE);
530
531 mhwmp_dbg(sdata, "received PREQ from %pM\n", orig_addr);
532
533 if (ether_addr_equal(target_addr, sdata->vif.addr)) {
534 mhwmp_dbg(sdata, "PREQ is for us\n");
535 forward = false;
536 reply = true;
537 metric = 0;
538 if (time_after(jiffies, ifmsh->last_sn_update +
539 net_traversal_jiffies(sdata)) ||
540 time_before(jiffies, ifmsh->last_sn_update)) {
541 target_sn = ++ifmsh->sn;
542 ifmsh->last_sn_update = jiffies;
543 }
544 } else if (is_broadcast_ether_addr(target_addr) &&
545 (target_flags & IEEE80211_PREQ_TO_FLAG)) {
546 rcu_read_lock();
547 mpath = mesh_path_lookup(orig_addr, sdata);
548 if (mpath) {
549 if (flags & IEEE80211_PREQ_PROACTIVE_PREP_FLAG) {
550 reply = true;
551 target_addr = sdata->vif.addr;
552 target_sn = ++ifmsh->sn;
553 metric = 0;
554 ifmsh->last_sn_update = jiffies;
555 }
556 if (root_is_gate)
557 mesh_path_add_gate(mpath);
558 }
559 rcu_read_unlock();
560 } else {
561 rcu_read_lock();
562 mpath = mesh_path_lookup(target_addr, sdata);
563 if (mpath) {
564 if ((!(mpath->flags & MESH_PATH_SN_VALID)) ||
565 SN_LT(mpath->sn, target_sn)) {
566 mpath->sn = target_sn;
567 mpath->flags |= MESH_PATH_SN_VALID;
568 } else if ((!(target_flags & MP_F_DO)) &&
569 (mpath->flags & MESH_PATH_ACTIVE)) {
570 reply = true;
571 metric = mpath->metric;
572 target_sn = mpath->sn;
573 if (target_flags & MP_F_RF)
574 target_flags |= MP_F_DO;
575 else
576 forward = false;
577 }
578 }
579 rcu_read_unlock();
580 }
581
582 if (reply) {
583 lifetime = PREQ_IE_LIFETIME(preq_elem);
584 ttl = ifmsh->mshcfg.element_ttl;
585 if (ttl != 0) {
586 mhwmp_dbg(sdata, "replying to the PREQ\n");
587 mesh_path_sel_frame_tx(MPATH_PREP, 0, orig_addr,
588 cpu_to_le32(orig_sn), 0, target_addr,
589 cpu_to_le32(target_sn), mgmt->sa, 0, ttl,
590 cpu_to_le32(lifetime), cpu_to_le32(metric),
591 0, sdata);
592 } else {
593 ifmsh->mshstats.dropped_frames_ttl++;
594 }
595 }
596
597 if (forward && ifmsh->mshcfg.dot11MeshForwarding) {
598 u32 preq_id;
599 u8 hopcount;
600
601 ttl = PREQ_IE_TTL(preq_elem);
602 lifetime = PREQ_IE_LIFETIME(preq_elem);
603 if (ttl <= 1) {
604 ifmsh->mshstats.dropped_frames_ttl++;
605 return;
606 }
607 mhwmp_dbg(sdata, "forwarding the PREQ from %pM\n", orig_addr);
608 --ttl;
609 preq_id = PREQ_IE_PREQ_ID(preq_elem);
610 hopcount = PREQ_IE_HOPCOUNT(preq_elem) + 1;
611 da = (mpath && mpath->is_root) ?
612 mpath->rann_snd_addr : broadcast_addr;
613
614 if (flags & IEEE80211_PREQ_PROACTIVE_PREP_FLAG) {
615 target_addr = PREQ_IE_TARGET_ADDR(preq_elem);
616 target_sn = PREQ_IE_TARGET_SN(preq_elem);
617 metric = orig_metric;
618 }
619
620 mesh_path_sel_frame_tx(MPATH_PREQ, flags, orig_addr,
621 cpu_to_le32(orig_sn), target_flags, target_addr,
622 cpu_to_le32(target_sn), da,
623 hopcount, ttl, cpu_to_le32(lifetime),
624 cpu_to_le32(metric), cpu_to_le32(preq_id),
625 sdata);
626 if (!is_multicast_ether_addr(da))
627 ifmsh->mshstats.fwded_unicast++;
628 else
629 ifmsh->mshstats.fwded_mcast++;
630 ifmsh->mshstats.fwded_frames++;
631 }
632 }
633
634
635 static inline struct sta_info *
636 next_hop_deref_protected(struct mesh_path *mpath)
637 {
638 return rcu_dereference_protected(mpath->next_hop,
639 lockdep_is_held(&mpath->state_lock));
640 }
641
642
643 static void hwmp_prep_frame_process(struct ieee80211_sub_if_data *sdata,
644 struct ieee80211_mgmt *mgmt,
645 u8 *prep_elem, u32 metric)
646 {
647 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
648 struct mesh_path *mpath;
649 u8 *target_addr, *orig_addr;
650 u8 ttl, hopcount, flags;
651 u8 next_hop[ETH_ALEN];
652 u32 target_sn, orig_sn, lifetime;
653
654 mhwmp_dbg(sdata, "received PREP from %pM\n",
655 PREP_IE_ORIG_ADDR(prep_elem));
656
657 orig_addr = PREP_IE_ORIG_ADDR(prep_elem);
658 if (ether_addr_equal(orig_addr, sdata->vif.addr))
659 /* destination, no forwarding required */
660 return;
661
662 if (!ifmsh->mshcfg.dot11MeshForwarding)
663 return;
664
665 ttl = PREP_IE_TTL(prep_elem);
666 if (ttl <= 1) {
667 sdata->u.mesh.mshstats.dropped_frames_ttl++;
668 return;
669 }
670
671 rcu_read_lock();
672 mpath = mesh_path_lookup(orig_addr, sdata);
673 if (mpath)
674 spin_lock_bh(&mpath->state_lock);
675 else
676 goto fail;
677 if (!(mpath->flags & MESH_PATH_ACTIVE)) {
678 spin_unlock_bh(&mpath->state_lock);
679 goto fail;
680 }
681 memcpy(next_hop, next_hop_deref_protected(mpath)->sta.addr, ETH_ALEN);
682 spin_unlock_bh(&mpath->state_lock);
683 --ttl;
684 flags = PREP_IE_FLAGS(prep_elem);
685 lifetime = PREP_IE_LIFETIME(prep_elem);
686 hopcount = PREP_IE_HOPCOUNT(prep_elem) + 1;
687 target_addr = PREP_IE_TARGET_ADDR(prep_elem);
688 target_sn = PREP_IE_TARGET_SN(prep_elem);
689 orig_sn = PREP_IE_ORIG_SN(prep_elem);
690
691 mesh_path_sel_frame_tx(MPATH_PREP, flags, orig_addr,
692 cpu_to_le32(orig_sn), 0, target_addr,
693 cpu_to_le32(target_sn), next_hop, hopcount,
694 ttl, cpu_to_le32(lifetime), cpu_to_le32(metric),
695 0, sdata);
696 rcu_read_unlock();
697
698 sdata->u.mesh.mshstats.fwded_unicast++;
699 sdata->u.mesh.mshstats.fwded_frames++;
700 return;
701
702 fail:
703 rcu_read_unlock();
704 sdata->u.mesh.mshstats.dropped_frames_no_route++;
705 }
706
707 static void hwmp_perr_frame_process(struct ieee80211_sub_if_data *sdata,
708 struct ieee80211_mgmt *mgmt, u8 *perr_elem)
709 {
710 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
711 struct mesh_path *mpath;
712 u8 ttl;
713 u8 *ta, *target_addr;
714 u32 target_sn;
715 u16 target_rcode;
716
717 ta = mgmt->sa;
718 ttl = PERR_IE_TTL(perr_elem);
719 if (ttl <= 1) {
720 ifmsh->mshstats.dropped_frames_ttl++;
721 return;
722 }
723 ttl--;
724 target_addr = PERR_IE_TARGET_ADDR(perr_elem);
725 target_sn = PERR_IE_TARGET_SN(perr_elem);
726 target_rcode = PERR_IE_TARGET_RCODE(perr_elem);
727
728 rcu_read_lock();
729 mpath = mesh_path_lookup(target_addr, sdata);
730 if (mpath) {
731 struct sta_info *sta;
732
733 spin_lock_bh(&mpath->state_lock);
734 sta = next_hop_deref_protected(mpath);
735 if (mpath->flags & MESH_PATH_ACTIVE &&
736 ether_addr_equal(ta, sta->sta.addr) &&
737 (!(mpath->flags & MESH_PATH_SN_VALID) ||
738 SN_GT(target_sn, mpath->sn))) {
739 mpath->flags &= ~MESH_PATH_ACTIVE;
740 mpath->sn = target_sn;
741 spin_unlock_bh(&mpath->state_lock);
742 if (!ifmsh->mshcfg.dot11MeshForwarding)
743 goto endperr;
744 mesh_path_error_tx(ttl, target_addr, cpu_to_le32(target_sn),
745 cpu_to_le16(target_rcode),
746 broadcast_addr, sdata);
747 } else
748 spin_unlock_bh(&mpath->state_lock);
749 }
750 endperr:
751 rcu_read_unlock();
752 }
753
754 static void hwmp_rann_frame_process(struct ieee80211_sub_if_data *sdata,
755 struct ieee80211_mgmt *mgmt,
756 struct ieee80211_rann_ie *rann)
757 {
758 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
759 struct ieee80211_local *local = sdata->local;
760 struct sta_info *sta;
761 struct mesh_path *mpath;
762 u8 ttl, flags, hopcount;
763 u8 *orig_addr;
764 u32 orig_sn, metric, metric_txsta, interval;
765 bool root_is_gate;
766
767 ttl = rann->rann_ttl;
768 flags = rann->rann_flags;
769 root_is_gate = !!(flags & RANN_FLAG_IS_GATE);
770 orig_addr = rann->rann_addr;
771 orig_sn = le32_to_cpu(rann->rann_seq);
772 interval = le32_to_cpu(rann->rann_interval);
773 hopcount = rann->rann_hopcount;
774 hopcount++;
775 metric = le32_to_cpu(rann->rann_metric);
776
777 /* Ignore our own RANNs */
778 if (ether_addr_equal(orig_addr, sdata->vif.addr))
779 return;
780
781 mhwmp_dbg(sdata,
782 "received RANN from %pM via neighbour %pM (is_gate=%d)\n",
783 orig_addr, mgmt->sa, root_is_gate);
784
785 rcu_read_lock();
786 sta = sta_info_get(sdata, mgmt->sa);
787 if (!sta) {
788 rcu_read_unlock();
789 return;
790 }
791
792 metric_txsta = airtime_link_metric_get(local, sta);
793
794 mpath = mesh_path_lookup(orig_addr, sdata);
795 if (!mpath) {
796 mesh_path_add(orig_addr, sdata);
797 mpath = mesh_path_lookup(orig_addr, sdata);
798 if (!mpath) {
799 rcu_read_unlock();
800 sdata->u.mesh.mshstats.dropped_frames_no_route++;
801 return;
802 }
803 }
804
805 if (!(SN_LT(mpath->sn, orig_sn)) &&
806 !(mpath->sn == orig_sn && metric < mpath->rann_metric)) {
807 rcu_read_unlock();
808 return;
809 }
810
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)) {
816 mhwmp_dbg(sdata,
817 "time to refresh root mpath %pM\n",
818 orig_addr);
819 mesh_queue_preq(mpath, PREQ_Q_F_START | PREQ_Q_F_REFRESH);
820 mpath->last_preq_to_root = jiffies;
821 }
822
823 mpath->sn = orig_sn;
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);
829
830 if (root_is_gate)
831 mesh_path_add_gate(mpath);
832
833 if (ttl <= 1) {
834 ifmsh->mshstats.dropped_frames_ttl++;
835 rcu_read_unlock();
836 return;
837 }
838 ttl--;
839
840 if (ifmsh->mshcfg.dot11MeshForwarding) {
841 mesh_path_sel_frame_tx(MPATH_RANN, flags, orig_addr,
842 cpu_to_le32(orig_sn),
843 0, NULL, 0, broadcast_addr,
844 hopcount, ttl, cpu_to_le32(interval),
845 cpu_to_le32(metric + metric_txsta),
846 0, sdata);
847 }
848
849 rcu_read_unlock();
850 }
851
852
853 void mesh_rx_path_sel_frame(struct ieee80211_sub_if_data *sdata,
854 struct ieee80211_mgmt *mgmt,
855 size_t len)
856 {
857 struct ieee802_11_elems elems;
858 size_t baselen;
859 u32 last_hop_metric;
860 struct sta_info *sta;
861
862 /* need action_code */
863 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
864 return;
865
866 rcu_read_lock();
867 sta = sta_info_get(sdata, mgmt->sa);
868 if (!sta || sta->plink_state != NL80211_PLINK_ESTAB) {
869 rcu_read_unlock();
870 return;
871 }
872 rcu_read_unlock();
873
874 baselen = (u8 *) mgmt->u.action.u.mesh_action.variable - (u8 *) mgmt;
875 ieee802_11_parse_elems(mgmt->u.action.u.mesh_action.variable,
876 len - baselen, &elems);
877
878 if (elems.preq) {
879 if (elems.preq_len != 37)
880 /* Right now we support just 1 destination and no AE */
881 return;
882 last_hop_metric = hwmp_route_info_get(sdata, mgmt, elems.preq,
883 MPATH_PREQ);
884 if (last_hop_metric)
885 hwmp_preq_frame_process(sdata, mgmt, elems.preq,
886 last_hop_metric);
887 }
888 if (elems.prep) {
889 if (elems.prep_len != 31)
890 /* Right now we support no AE */
891 return;
892 last_hop_metric = hwmp_route_info_get(sdata, mgmt, elems.prep,
893 MPATH_PREP);
894 if (last_hop_metric)
895 hwmp_prep_frame_process(sdata, mgmt, elems.prep,
896 last_hop_metric);
897 }
898 if (elems.perr) {
899 if (elems.perr_len != 15)
900 /* Right now we support only one destination per PERR */
901 return;
902 hwmp_perr_frame_process(sdata, mgmt, elems.perr);
903 }
904 if (elems.rann)
905 hwmp_rann_frame_process(sdata, mgmt, elems.rann);
906 }
907
908 /**
909 * mesh_queue_preq - queue a PREQ to a given destination
910 *
911 * @mpath: mesh path to discover
912 * @flags: special attributes of the PREQ to be sent
913 *
914 * Locking: the function must be called from within a rcu read lock block.
915 *
916 */
917 static void mesh_queue_preq(struct mesh_path *mpath, u8 flags)
918 {
919 struct ieee80211_sub_if_data *sdata = mpath->sdata;
920 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
921 struct mesh_preq_queue *preq_node;
922
923 preq_node = kmalloc(sizeof(struct mesh_preq_queue), GFP_ATOMIC);
924 if (!preq_node) {
925 mhwmp_dbg(sdata, "could not allocate PREQ node\n");
926 return;
927 }
928
929 spin_lock_bh(&ifmsh->mesh_preq_queue_lock);
930 if (ifmsh->preq_queue_len == MAX_PREQ_QUEUE_LEN) {
931 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
932 kfree(preq_node);
933 if (printk_ratelimit())
934 mhwmp_dbg(sdata, "PREQ node queue full\n");
935 return;
936 }
937
938 spin_lock(&mpath->state_lock);
939 if (mpath->flags & MESH_PATH_REQ_QUEUED) {
940 spin_unlock(&mpath->state_lock);
941 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
942 kfree(preq_node);
943 return;
944 }
945
946 memcpy(preq_node->dst, mpath->dst, ETH_ALEN);
947 preq_node->flags = flags;
948
949 mpath->flags |= MESH_PATH_REQ_QUEUED;
950 spin_unlock(&mpath->state_lock);
951
952 list_add_tail(&preq_node->list, &ifmsh->preq_queue.list);
953 ++ifmsh->preq_queue_len;
954 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
955
956 if (time_after(jiffies, ifmsh->last_preq + min_preq_int_jiff(sdata)))
957 ieee80211_queue_work(&sdata->local->hw, &sdata->work);
958
959 else if (time_before(jiffies, ifmsh->last_preq)) {
960 /* avoid long wait if did not send preqs for a long time
961 * and jiffies wrapped around
962 */
963 ifmsh->last_preq = jiffies - min_preq_int_jiff(sdata) - 1;
964 ieee80211_queue_work(&sdata->local->hw, &sdata->work);
965 } else
966 mod_timer(&ifmsh->mesh_path_timer, ifmsh->last_preq +
967 min_preq_int_jiff(sdata));
968 }
969
970 /**
971 * mesh_path_start_discovery - launch a path discovery from the PREQ queue
972 *
973 * @sdata: local mesh subif
974 */
975 void mesh_path_start_discovery(struct ieee80211_sub_if_data *sdata)
976 {
977 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
978 struct mesh_preq_queue *preq_node;
979 struct mesh_path *mpath;
980 u8 ttl, target_flags;
981 const u8 *da;
982 u32 lifetime;
983
984 spin_lock_bh(&ifmsh->mesh_preq_queue_lock);
985 if (!ifmsh->preq_queue_len ||
986 time_before(jiffies, ifmsh->last_preq +
987 min_preq_int_jiff(sdata))) {
988 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
989 return;
990 }
991
992 preq_node = list_first_entry(&ifmsh->preq_queue.list,
993 struct mesh_preq_queue, list);
994 list_del(&preq_node->list);
995 --ifmsh->preq_queue_len;
996 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
997
998 rcu_read_lock();
999 mpath = mesh_path_lookup(preq_node->dst, sdata);
1000 if (!mpath)
1001 goto enddiscovery;
1002
1003 spin_lock_bh(&mpath->state_lock);
1004 mpath->flags &= ~MESH_PATH_REQ_QUEUED;
1005 if (preq_node->flags & PREQ_Q_F_START) {
1006 if (mpath->flags & MESH_PATH_RESOLVING) {
1007 spin_unlock_bh(&mpath->state_lock);
1008 goto enddiscovery;
1009 } else {
1010 mpath->flags &= ~MESH_PATH_RESOLVED;
1011 mpath->flags |= MESH_PATH_RESOLVING;
1012 mpath->discovery_retries = 0;
1013 mpath->discovery_timeout = disc_timeout_jiff(sdata);
1014 }
1015 } else if (!(mpath->flags & MESH_PATH_RESOLVING) ||
1016 mpath->flags & MESH_PATH_RESOLVED) {
1017 mpath->flags &= ~MESH_PATH_RESOLVING;
1018 spin_unlock_bh(&mpath->state_lock);
1019 goto enddiscovery;
1020 }
1021
1022 ifmsh->last_preq = jiffies;
1023
1024 if (time_after(jiffies, ifmsh->last_sn_update +
1025 net_traversal_jiffies(sdata)) ||
1026 time_before(jiffies, ifmsh->last_sn_update)) {
1027 ++ifmsh->sn;
1028 sdata->u.mesh.last_sn_update = jiffies;
1029 }
1030 lifetime = default_lifetime(sdata);
1031 ttl = sdata->u.mesh.mshcfg.element_ttl;
1032 if (ttl == 0) {
1033 sdata->u.mesh.mshstats.dropped_frames_ttl++;
1034 spin_unlock_bh(&mpath->state_lock);
1035 goto enddiscovery;
1036 }
1037
1038 if (preq_node->flags & PREQ_Q_F_REFRESH)
1039 target_flags = MP_F_DO;
1040 else
1041 target_flags = MP_F_RF;
1042
1043 spin_unlock_bh(&mpath->state_lock);
1044 da = (mpath->is_root) ? mpath->rann_snd_addr : broadcast_addr;
1045 mesh_path_sel_frame_tx(MPATH_PREQ, 0, sdata->vif.addr,
1046 cpu_to_le32(ifmsh->sn), target_flags, mpath->dst,
1047 cpu_to_le32(mpath->sn), da, 0,
1048 ttl, cpu_to_le32(lifetime), 0,
1049 cpu_to_le32(ifmsh->preq_id++), sdata);
1050 mod_timer(&mpath->timer, jiffies + mpath->discovery_timeout);
1051
1052 enddiscovery:
1053 rcu_read_unlock();
1054 kfree(preq_node);
1055 }
1056
1057 /**
1058 * mesh_nexthop_resolve - lookup next hop; conditionally start path discovery
1059 *
1060 * @skb: 802.11 frame to be sent
1061 * @sdata: network subif the frame will be sent through
1062 *
1063 * Lookup next hop for given skb and start path discovery if no
1064 * forwarding information is found.
1065 *
1066 * Returns: 0 if the next hop was found and -ENOENT if the frame was queued.
1067 * skb is freeed here if no mpath could be allocated.
1068 */
1069 int mesh_nexthop_resolve(struct sk_buff *skb,
1070 struct ieee80211_sub_if_data *sdata)
1071 {
1072 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1073 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1074 struct mesh_path *mpath;
1075 struct sk_buff *skb_to_free = NULL;
1076 u8 *target_addr = hdr->addr3;
1077 int err = 0;
1078
1079 rcu_read_lock();
1080 err = mesh_nexthop_lookup(skb, sdata);
1081 if (!err)
1082 goto endlookup;
1083
1084 /* no nexthop found, start resolving */
1085 mpath = mesh_path_lookup(target_addr, sdata);
1086 if (!mpath) {
1087 mesh_path_add(target_addr, sdata);
1088 mpath = mesh_path_lookup(target_addr, sdata);
1089 if (!mpath) {
1090 mesh_path_discard_frame(skb, sdata);
1091 err = -ENOSPC;
1092 goto endlookup;
1093 }
1094 }
1095
1096 if (!(mpath->flags & MESH_PATH_RESOLVING))
1097 mesh_queue_preq(mpath, PREQ_Q_F_START);
1098
1099 if (skb_queue_len(&mpath->frame_queue) >= MESH_FRAME_QUEUE_LEN)
1100 skb_to_free = skb_dequeue(&mpath->frame_queue);
1101
1102 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1103 ieee80211_set_qos_hdr(sdata, skb);
1104 skb_queue_tail(&mpath->frame_queue, skb);
1105 err = -ENOENT;
1106 if (skb_to_free)
1107 mesh_path_discard_frame(skb_to_free, sdata);
1108
1109 endlookup:
1110 rcu_read_unlock();
1111 return err;
1112 }
1113 /**
1114 * mesh_nexthop_lookup - put the appropriate next hop on a mesh frame. Calling
1115 * this function is considered "using" the associated mpath, so preempt a path
1116 * refresh if this mpath expires soon.
1117 *
1118 * @skb: 802.11 frame to be sent
1119 * @sdata: network subif the frame will be sent through
1120 *
1121 * Returns: 0 if the next hop was found. Nonzero otherwise.
1122 */
1123 int mesh_nexthop_lookup(struct sk_buff *skb,
1124 struct ieee80211_sub_if_data *sdata)
1125 {
1126 struct mesh_path *mpath;
1127 struct sta_info *next_hop;
1128 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1129 u8 *target_addr = hdr->addr3;
1130 int err = -ENOENT;
1131
1132 rcu_read_lock();
1133 mpath = mesh_path_lookup(target_addr, sdata);
1134
1135 if (!mpath || !(mpath->flags & MESH_PATH_ACTIVE))
1136 goto endlookup;
1137
1138 if (time_after(jiffies,
1139 mpath->exp_time -
1140 msecs_to_jiffies(sdata->u.mesh.mshcfg.path_refresh_time)) &&
1141 ether_addr_equal(sdata->vif.addr, hdr->addr4) &&
1142 !(mpath->flags & MESH_PATH_RESOLVING) &&
1143 !(mpath->flags & MESH_PATH_FIXED))
1144 mesh_queue_preq(mpath, PREQ_Q_F_START | PREQ_Q_F_REFRESH);
1145
1146 next_hop = rcu_dereference(mpath->next_hop);
1147 if (next_hop) {
1148 memcpy(hdr->addr1, next_hop->sta.addr, ETH_ALEN);
1149 memcpy(hdr->addr2, sdata->vif.addr, ETH_ALEN);
1150 err = 0;
1151 }
1152
1153 endlookup:
1154 rcu_read_unlock();
1155 return err;
1156 }
1157
1158 void mesh_path_timer(unsigned long data)
1159 {
1160 struct mesh_path *mpath = (void *) data;
1161 struct ieee80211_sub_if_data *sdata = mpath->sdata;
1162 int ret;
1163
1164 if (sdata->local->quiescing)
1165 return;
1166
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);
1178 } else {
1179 mpath->flags = 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);
1184 if (ret)
1185 mhwmp_dbg(sdata, "no gate was reachable\n");
1186 } else
1187 mesh_path_flush_pending(mpath);
1188 }
1189 }
1190
1191 void
1192 mesh_path_tx_root_frame(struct ieee80211_sub_if_data *sdata)
1193 {
1194 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1195 u32 interval = ifmsh->mshcfg.dot11MeshHWMPRannInterval;
1196 u8 flags, target_flags = 0;
1197
1198 flags = (ifmsh->mshcfg.dot11MeshGateAnnouncementProtocol)
1199 ? RANN_FLAG_IS_GATE : 0;
1200
1201 switch (ifmsh->mshcfg.dot11MeshHWMPRootMode) {
1202 case IEEE80211_PROACTIVE_RANN:
1203 mesh_path_sel_frame_tx(MPATH_RANN, flags, sdata->vif.addr,
1204 cpu_to_le32(++ifmsh->sn),
1205 0, NULL, 0, broadcast_addr,
1206 0, ifmsh->mshcfg.element_ttl,
1207 cpu_to_le32(interval), 0, 0, sdata);
1208 break;
1209 case IEEE80211_PROACTIVE_PREQ_WITH_PREP:
1210 flags |= IEEE80211_PREQ_PROACTIVE_PREP_FLAG;
1211 case IEEE80211_PROACTIVE_PREQ_NO_PREP:
1212 interval = ifmsh->mshcfg.dot11MeshHWMPactivePathToRootTimeout;
1213 target_flags |= IEEE80211_PREQ_TO_FLAG |
1214 IEEE80211_PREQ_USN_FLAG;
1215 mesh_path_sel_frame_tx(MPATH_PREQ, flags, sdata->vif.addr,
1216 cpu_to_le32(++ifmsh->sn), target_flags,
1217 (u8 *) broadcast_addr, 0, broadcast_addr,
1218 0, ifmsh->mshcfg.element_ttl,
1219 cpu_to_le32(interval),
1220 0, cpu_to_le32(ifmsh->preq_id++), sdata);
1221 break;
1222 default:
1223 mhwmp_dbg(sdata, "Proactive mechanism not supported\n");
1224 return;
1225 }
1226 }
Linux with added FPC-III support