1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (c) 2008, 2009 open80211s Ltd.
4 * Copyright (C) 2023 Intel Corporation
5 * Author: Luis Carlos Cobo <luisca@cozybit.com>
6 */
7
8#include <linux/etherdevice.h>
9#include <linux/list.h>
10#include <linux/random.h>
11#include <linux/slab.h>
12#include <linux/spinlock.h>
13#include <linux/string.h>
14#include <net/mac80211.h>
15#include "wme.h"
16#include "ieee80211_i.h"
17#include "mesh.h"
18#include <linux/rhashtable.h>
19
20static void mesh_path_free_rcu(struct mesh_table *tbl, struct mesh_path *mpath);
21
22static u32 mesh_table_hash(const void *addr, u32 len, u32 seed)
23{
24 /* Use last four bytes of hw addr as hash index */
25 return jhash_1word(a: __get_unaligned_cpu32(p: (u8 *)addr + 2), initval: seed);
26}
27
28static const struct rhashtable_params mesh_rht_params = {
29 .nelem_hint = 2,
30 .automatic_shrinking = true,
31 .key_len = ETH_ALEN,
32 .key_offset = offsetof(struct mesh_path, dst),
33 .head_offset = offsetof(struct mesh_path, rhash),
34 .hashfn = mesh_table_hash,
35};
36
37static const struct rhashtable_params fast_tx_rht_params = {
38 .nelem_hint = 10,
39 .automatic_shrinking = true,
40 .key_len = ETH_ALEN,
41 .key_offset = offsetof(struct ieee80211_mesh_fast_tx, addr_key),
42 .head_offset = offsetof(struct ieee80211_mesh_fast_tx, rhash),
43 .hashfn = mesh_table_hash,
44};
45
46static void __mesh_fast_tx_entry_free(void *ptr, void *tblptr)
47{
48 struct ieee80211_mesh_fast_tx *entry = ptr;
49
50 kfree_rcu(entry, fast_tx.rcu_head);
51}
52
53static void mesh_fast_tx_deinit(struct ieee80211_sub_if_data *sdata)
54{
55 struct mesh_tx_cache *cache;
56
57 cache = &sdata->u.mesh.tx_cache;
58 rhashtable_free_and_destroy(ht: &cache->rht,
59 free_fn: __mesh_fast_tx_entry_free, NULL);
60}
61
62static void mesh_fast_tx_init(struct ieee80211_sub_if_data *sdata)
63{
64 struct mesh_tx_cache *cache;
65
66 cache = &sdata->u.mesh.tx_cache;
67 rhashtable_init(ht: &cache->rht, params: &fast_tx_rht_params);
68 INIT_HLIST_HEAD(&cache->walk_head);
69 spin_lock_init(&cache->walk_lock);
70}
71
72static inline bool mpath_expired(struct mesh_path *mpath)
73{
74 return (mpath->flags & MESH_PATH_ACTIVE) &&
75 time_after(jiffies, mpath->exp_time) &&
76 !(mpath->flags & MESH_PATH_FIXED);
77}
78
79static void mesh_path_rht_free(void *ptr, void *tblptr)
80{
81 struct mesh_path *mpath = ptr;
82 struct mesh_table *tbl = tblptr;
83
84 mesh_path_free_rcu(tbl, mpath);
85}
86
87static void mesh_table_init(struct mesh_table *tbl)
88{
89 INIT_HLIST_HEAD(&tbl->known_gates);
90 INIT_HLIST_HEAD(&tbl->walk_head);
91 atomic_set(v: &tbl->entries, i: 0);
92 spin_lock_init(&tbl->gates_lock);
93 spin_lock_init(&tbl->walk_lock);
94
95 /* rhashtable_init() may fail only in case of wrong
96 * mesh_rht_params
97 */
98 WARN_ON(rhashtable_init(&tbl->rhead, &mesh_rht_params));
99}
100
101static void mesh_table_free(struct mesh_table *tbl)
102{
103 rhashtable_free_and_destroy(ht: &tbl->rhead,
104 free_fn: mesh_path_rht_free, arg: tbl);
105}
106
107/**
108 * mesh_path_assign_nexthop - update mesh path next hop
109 *
110 * @mpath: mesh path to update
111 * @sta: next hop to assign
112 *
113 * Locking: mpath->state_lock must be held when calling this function
114 */
115void mesh_path_assign_nexthop(struct mesh_path *mpath, struct sta_info *sta)
116{
117 struct sk_buff *skb;
118 struct ieee80211_hdr *hdr;
119 unsigned long flags;
120
121 rcu_assign_pointer(mpath->next_hop, sta);
122
123 spin_lock_irqsave(&mpath->frame_queue.lock, flags);
124 skb_queue_walk(&mpath->frame_queue, skb) {
125 hdr = (struct ieee80211_hdr *) skb->data;
126 memcpy(hdr->addr1, sta->sta.addr, ETH_ALEN);
127 memcpy(hdr->addr2, mpath->sdata->vif.addr, ETH_ALEN);
128 ieee80211_mps_set_frame_flags(sdata: sta->sdata, sta, hdr);
129 }
130
131 spin_unlock_irqrestore(lock: &mpath->frame_queue.lock, flags);
132}
133
134static void prepare_for_gate(struct sk_buff *skb, char *dst_addr,
135 struct mesh_path *gate_mpath)
136{
137 struct ieee80211_hdr *hdr;
138 struct ieee80211s_hdr *mshdr;
139 int mesh_hdrlen, hdrlen;
140 char *next_hop;
141
142 hdr = (struct ieee80211_hdr *) skb->data;
143 hdrlen = ieee80211_hdrlen(fc: hdr->frame_control);
144 mshdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
145
146 if (!(mshdr->flags & MESH_FLAGS_AE)) {
147 /* size of the fixed part of the mesh header */
148 mesh_hdrlen = 6;
149
150 /* make room for the two extended addresses */
151 skb_push(skb, len: 2 * ETH_ALEN);
152 memmove(skb->data, hdr, hdrlen + mesh_hdrlen);
153
154 hdr = (struct ieee80211_hdr *) skb->data;
155
156 /* we preserve the previous mesh header and only add
157 * the new addresses */
158 mshdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
159 mshdr->flags = MESH_FLAGS_AE_A5_A6;
160 memcpy(mshdr->eaddr1, hdr->addr3, ETH_ALEN);
161 memcpy(mshdr->eaddr2, hdr->addr4, ETH_ALEN);
162 }
163
164 /* update next hop */
165 hdr = (struct ieee80211_hdr *) skb->data;
166 rcu_read_lock();
167 next_hop = rcu_dereference(gate_mpath->next_hop)->sta.addr;
168 memcpy(hdr->addr1, next_hop, ETH_ALEN);
169 rcu_read_unlock();
170 memcpy(hdr->addr2, gate_mpath->sdata->vif.addr, ETH_ALEN);
171 memcpy(hdr->addr3, dst_addr, ETH_ALEN);
172}
173
174/**
175 * mesh_path_move_to_queue - Move or copy frames from one mpath queue to another
176 *
177 * @gate_mpath: An active mpath the frames will be sent to (i.e. the gate)
178 * @from_mpath: The failed mpath
179 * @copy: When true, copy all the frames to the new mpath queue. When false,
180 * move them.
181 *
182 * This function is used to transfer or copy frames from an unresolved mpath to
183 * a gate mpath. The function also adds the Address Extension field and
184 * updates the next hop.
185 *
186 * If a frame already has an Address Extension field, only the next hop and
187 * destination addresses are updated.
188 *
189 * The gate mpath must be an active mpath with a valid mpath->next_hop.
190 */
191static void mesh_path_move_to_queue(struct mesh_path *gate_mpath,
192 struct mesh_path *from_mpath,
193 bool copy)
194{
195 struct sk_buff *skb, *fskb, *tmp;
196 struct sk_buff_head failq;
197 unsigned long flags;
198
199 if (WARN_ON(gate_mpath == from_mpath))
200 return;
201 if (WARN_ON(!gate_mpath->next_hop))
202 return;
203
204 __skb_queue_head_init(list: &failq);
205
206 spin_lock_irqsave(&from_mpath->frame_queue.lock, flags);
207 skb_queue_splice_init(list: &from_mpath->frame_queue, head: &failq);
208 spin_unlock_irqrestore(lock: &from_mpath->frame_queue.lock, flags);
209
210 skb_queue_walk_safe(&failq, fskb, tmp) {
211 if (skb_queue_len(list_: &gate_mpath->frame_queue) >=
212 MESH_FRAME_QUEUE_LEN) {
213 mpath_dbg(gate_mpath->sdata, "mpath queue full!\n");
214 break;
215 }
216
217 skb = skb_copy(skb: fskb, GFP_ATOMIC);
218 if (WARN_ON(!skb))
219 break;
220
221 prepare_for_gate(skb, dst_addr: gate_mpath->dst, gate_mpath);
222 skb_queue_tail(list: &gate_mpath->frame_queue, newsk: skb);
223
224 if (copy)
225 continue;
226
227 __skb_unlink(skb: fskb, list: &failq);
228 kfree_skb(skb: fskb);
229 }
230
231 mpath_dbg(gate_mpath->sdata, "Mpath queue for gate %pM has %d frames\n",
232 gate_mpath->dst, skb_queue_len(&gate_mpath->frame_queue));
233
234 if (!copy)
235 return;
236
237 spin_lock_irqsave(&from_mpath->frame_queue.lock, flags);
238 skb_queue_splice(list: &failq, head: &from_mpath->frame_queue);
239 spin_unlock_irqrestore(lock: &from_mpath->frame_queue.lock, flags);
240}
241
242
243static struct mesh_path *mpath_lookup(struct mesh_table *tbl, const u8 *dst,
244 struct ieee80211_sub_if_data *sdata)
245{
246 struct mesh_path *mpath;
247
248 mpath = rhashtable_lookup(ht: &tbl->rhead, key: dst, params: mesh_rht_params);
249
250 if (mpath && mpath_expired(mpath)) {
251 spin_lock_bh(lock: &mpath->state_lock);
252 mpath->flags &= ~MESH_PATH_ACTIVE;
253 spin_unlock_bh(lock: &mpath->state_lock);
254 }
255 return mpath;
256}
257
258/**
259 * mesh_path_lookup - look up a path in the mesh path table
260 * @sdata: local subif
261 * @dst: hardware address (ETH_ALEN length) of destination
262 *
263 * Returns: pointer to the mesh path structure, or NULL if not found
264 *
265 * Locking: must be called within a read rcu section.
266 */
267struct mesh_path *
268mesh_path_lookup(struct ieee80211_sub_if_data *sdata, const u8 *dst)
269{
270 return mpath_lookup(tbl: &sdata->u.mesh.mesh_paths, dst, sdata);
271}
272
273struct mesh_path *
274mpp_path_lookup(struct ieee80211_sub_if_data *sdata, const u8 *dst)
275{
276 return mpath_lookup(tbl: &sdata->u.mesh.mpp_paths, dst, sdata);
277}
278
279static struct mesh_path *
280__mesh_path_lookup_by_idx(struct mesh_table *tbl, int idx)
281{
282 int i = 0;
283 struct mesh_path *mpath;
284
285 hlist_for_each_entry_rcu(mpath, &tbl->walk_head, walk_list) {
286 if (i++ == idx)
287 break;
288 }
289
290 if (!mpath)
291 return NULL;
292
293 if (mpath_expired(mpath)) {
294 spin_lock_bh(lock: &mpath->state_lock);
295 mpath->flags &= ~MESH_PATH_ACTIVE;
296 spin_unlock_bh(lock: &mpath->state_lock);
297 }
298 return mpath;
299}
300
301/**
302 * mesh_path_lookup_by_idx - look up a path in the mesh path table by its index
303 * @idx: index
304 * @sdata: local subif, or NULL for all entries
305 *
306 * Returns: pointer to the mesh path structure, or NULL if not found.
307 *
308 * Locking: must be called within a read rcu section.
309 */
310struct mesh_path *
311mesh_path_lookup_by_idx(struct ieee80211_sub_if_data *sdata, int idx)
312{
313 return __mesh_path_lookup_by_idx(tbl: &sdata->u.mesh.mesh_paths, idx);
314}
315
316/**
317 * mpp_path_lookup_by_idx - look up a path in the proxy path table by its index
318 * @idx: index
319 * @sdata: local subif, or NULL for all entries
320 *
321 * Returns: pointer to the proxy path structure, or NULL if not found.
322 *
323 * Locking: must be called within a read rcu section.
324 */
325struct mesh_path *
326mpp_path_lookup_by_idx(struct ieee80211_sub_if_data *sdata, int idx)
327{
328 return __mesh_path_lookup_by_idx(tbl: &sdata->u.mesh.mpp_paths, idx);
329}
330
331/**
332 * mesh_path_add_gate - add the given mpath to a mesh gate to our path table
333 * @mpath: gate path to add to table
334 *
335 * Returns: 0 on success, -EEXIST
336 */
337int mesh_path_add_gate(struct mesh_path *mpath)
338{
339 struct mesh_table *tbl;
340 int err;
341
342 rcu_read_lock();
343 tbl = &mpath->sdata->u.mesh.mesh_paths;
344
345 spin_lock_bh(lock: &mpath->state_lock);
346 if (mpath->is_gate) {
347 err = -EEXIST;
348 spin_unlock_bh(lock: &mpath->state_lock);
349 goto err_rcu;
350 }
351 mpath->is_gate = true;
352 mpath->sdata->u.mesh.num_gates++;
353
354 spin_lock(lock: &tbl->gates_lock);
355 hlist_add_head_rcu(n: &mpath->gate_list, h: &tbl->known_gates);
356 spin_unlock(lock: &tbl->gates_lock);
357
358 spin_unlock_bh(lock: &mpath->state_lock);
359
360 mpath_dbg(mpath->sdata,
361 "Mesh path: Recorded new gate: %pM. %d known gates\n",
362 mpath->dst, mpath->sdata->u.mesh.num_gates);
363 err = 0;
364err_rcu:
365 rcu_read_unlock();
366 return err;
367}
368
369/**
370 * mesh_gate_del - remove a mesh gate from the list of known gates
371 * @tbl: table which holds our list of known gates
372 * @mpath: gate mpath
373 */
374static void mesh_gate_del(struct mesh_table *tbl, struct mesh_path *mpath)
375{
376 lockdep_assert_held(&mpath->state_lock);
377 if (!mpath->is_gate)
378 return;
379
380 mpath->is_gate = false;
381 spin_lock_bh(lock: &tbl->gates_lock);
382 hlist_del_rcu(n: &mpath->gate_list);
383 mpath->sdata->u.mesh.num_gates--;
384 spin_unlock_bh(lock: &tbl->gates_lock);
385
386 mpath_dbg(mpath->sdata,
387 "Mesh path: Deleted gate: %pM. %d known gates\n",
388 mpath->dst, mpath->sdata->u.mesh.num_gates);
389}
390
391/**
392 * mesh_gate_num - number of gates known to this interface
393 * @sdata: subif data
394 *
395 * Returns: The number of gates
396 */
397int mesh_gate_num(struct ieee80211_sub_if_data *sdata)
398{
399 return sdata->u.mesh.num_gates;
400}
401
402static
403struct mesh_path *mesh_path_new(struct ieee80211_sub_if_data *sdata,
404 const u8 *dst, gfp_t gfp_flags)
405{
406 struct mesh_path *new_mpath;
407
408 new_mpath = kzalloc(size: sizeof(struct mesh_path), flags: gfp_flags);
409 if (!new_mpath)
410 return NULL;
411
412 memcpy(new_mpath->dst, dst, ETH_ALEN);
413 eth_broadcast_addr(addr: new_mpath->rann_snd_addr);
414 new_mpath->is_root = false;
415 new_mpath->sdata = sdata;
416 new_mpath->flags = 0;
417 skb_queue_head_init(list: &new_mpath->frame_queue);
418 new_mpath->exp_time = jiffies;
419 spin_lock_init(&new_mpath->state_lock);
420 timer_setup(&new_mpath->timer, mesh_path_timer, 0);
421
422 return new_mpath;
423}
424
425static void mesh_fast_tx_entry_free(struct mesh_tx_cache *cache,
426 struct ieee80211_mesh_fast_tx *entry)
427{
428 hlist_del_rcu(n: &entry->walk_list);
429 rhashtable_remove_fast(ht: &cache->rht, obj: &entry->rhash, params: fast_tx_rht_params);
430 kfree_rcu(entry, fast_tx.rcu_head);
431}
432
433struct ieee80211_mesh_fast_tx *
434mesh_fast_tx_get(struct ieee80211_sub_if_data *sdata, const u8 *addr)
435{
436 struct ieee80211_mesh_fast_tx *entry;
437 struct mesh_tx_cache *cache;
438
439 cache = &sdata->u.mesh.tx_cache;
440 entry = rhashtable_lookup(ht: &cache->rht, key: addr, params: fast_tx_rht_params);
441 if (!entry)
442 return NULL;
443
444 if (!(entry->mpath->flags & MESH_PATH_ACTIVE) ||
445 mpath_expired(mpath: entry->mpath)) {
446 spin_lock_bh(lock: &cache->walk_lock);
447 entry = rhashtable_lookup(ht: &cache->rht, key: addr, params: fast_tx_rht_params);
448 if (entry)
449 mesh_fast_tx_entry_free(cache, entry);
450 spin_unlock_bh(lock: &cache->walk_lock);
451 return NULL;
452 }
453
454 mesh_path_refresh(sdata, mpath: entry->mpath, NULL);
455 if (entry->mppath)
456 entry->mppath->exp_time = jiffies;
457 entry->timestamp = jiffies;
458
459 return entry;
460}
461
462void mesh_fast_tx_cache(struct ieee80211_sub_if_data *sdata,
463 struct sk_buff *skb, struct mesh_path *mpath)
464{
465 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
466 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
467 struct ieee80211_mesh_fast_tx *entry, *prev;
468 struct ieee80211_mesh_fast_tx build = {};
469 struct ieee80211s_hdr *meshhdr;
470 struct mesh_tx_cache *cache;
471 struct ieee80211_key *key;
472 struct mesh_path *mppath;
473 struct sta_info *sta;
474 u8 *qc;
475
476 if (sdata->noack_map ||
477 !ieee80211_is_data_qos(fc: hdr->frame_control))
478 return;
479
480 build.fast_tx.hdr_len = ieee80211_hdrlen(fc: hdr->frame_control);
481 meshhdr = (struct ieee80211s_hdr *)(skb->data + build.fast_tx.hdr_len);
482 build.hdrlen = ieee80211_get_mesh_hdrlen(meshhdr);
483
484 cache = &sdata->u.mesh.tx_cache;
485 if (atomic_read(v: &cache->rht.nelems) >= MESH_FAST_TX_CACHE_MAX_SIZE)
486 return;
487
488 sta = rcu_dereference(mpath->next_hop);
489 if (!sta)
490 return;
491
492 if ((meshhdr->flags & MESH_FLAGS_AE) == MESH_FLAGS_AE_A5_A6) {
493 /* This is required to keep the mppath alive */
494 mppath = mpp_path_lookup(sdata, dst: meshhdr->eaddr1);
495 if (!mppath)
496 return;
497 build.mppath = mppath;
498 } else if (ieee80211_has_a4(fc: hdr->frame_control)) {
499 mppath = mpath;
500 } else {
501 return;
502 }
503
504 /* rate limit, in case fast xmit can't be enabled */
505 if (mppath->fast_tx_check == jiffies)
506 return;
507
508 mppath->fast_tx_check = jiffies;
509
510 /*
511 * Same use of the sta lock as in ieee80211_check_fast_xmit, in order
512 * to protect against concurrent sta key updates.
513 */
514 spin_lock_bh(lock: &sta->lock);
515 key = rcu_access_pointer(sta->ptk[sta->ptk_idx]);
516 if (!key)
517 key = rcu_access_pointer(sdata->default_unicast_key);
518 build.fast_tx.key = key;
519
520 if (key) {
521 bool gen_iv, iv_spc;
522
523 gen_iv = key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV;
524 iv_spc = key->conf.flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE;
525
526 if (!(key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) ||
527 (key->flags & KEY_FLAG_TAINTED))
528 goto unlock_sta;
529
530 switch (key->conf.cipher) {
531 case WLAN_CIPHER_SUITE_CCMP:
532 case WLAN_CIPHER_SUITE_CCMP_256:
533 if (gen_iv)
534 build.fast_tx.pn_offs = build.fast_tx.hdr_len;
535 if (gen_iv || iv_spc)
536 build.fast_tx.hdr_len += IEEE80211_CCMP_HDR_LEN;
537 break;
538 case WLAN_CIPHER_SUITE_GCMP:
539 case WLAN_CIPHER_SUITE_GCMP_256:
540 if (gen_iv)
541 build.fast_tx.pn_offs = build.fast_tx.hdr_len;
542 if (gen_iv || iv_spc)
543 build.fast_tx.hdr_len += IEEE80211_GCMP_HDR_LEN;
544 break;
545 default:
546 goto unlock_sta;
547 }
548 }
549
550 memcpy(build.addr_key, mppath->dst, ETH_ALEN);
551 build.timestamp = jiffies;
552 build.fast_tx.band = info->band;
553 build.fast_tx.da_offs = offsetof(struct ieee80211_hdr, addr3);
554 build.fast_tx.sa_offs = offsetof(struct ieee80211_hdr, addr4);
555 build.mpath = mpath;
556 memcpy(build.hdr, meshhdr, build.hdrlen);
557 memcpy(build.hdr + build.hdrlen, rfc1042_header, sizeof(rfc1042_header));
558 build.hdrlen += sizeof(rfc1042_header);
559 memcpy(build.fast_tx.hdr, hdr, build.fast_tx.hdr_len);
560
561 hdr = (struct ieee80211_hdr *)build.fast_tx.hdr;
562 if (build.fast_tx.key)
563 hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
564
565 qc = ieee80211_get_qos_ctl(hdr);
566 qc[1] |= IEEE80211_QOS_CTL_MESH_CONTROL_PRESENT >> 8;
567
568 entry = kmemdup(p: &build, size: sizeof(build), GFP_ATOMIC);
569 if (!entry)
570 goto unlock_sta;
571
572 spin_lock(lock: &cache->walk_lock);
573 prev = rhashtable_lookup_get_insert_fast(ht: &cache->rht,
574 obj: &entry->rhash,
575 params: fast_tx_rht_params);
576 if (unlikely(IS_ERR(prev))) {
577 kfree(objp: entry);
578 goto unlock_cache;
579 }
580
581 /*
582 * replace any previous entry in the hash table, in case we're
583 * replacing it with a different type (e.g. mpath -> mpp)
584 */
585 if (unlikely(prev)) {
586 rhashtable_replace_fast(ht: &cache->rht, obj_old: &prev->rhash,
587 obj_new: &entry->rhash, params: fast_tx_rht_params);
588 hlist_del_rcu(n: &prev->walk_list);
589 kfree_rcu(prev, fast_tx.rcu_head);
590 }
591
592 hlist_add_head(n: &entry->walk_list, h: &cache->walk_head);
593
594unlock_cache:
595 spin_unlock(lock: &cache->walk_lock);
596unlock_sta:
597 spin_unlock_bh(lock: &sta->lock);
598}
599
600void mesh_fast_tx_gc(struct ieee80211_sub_if_data *sdata)
601{
602 unsigned long timeout = msecs_to_jiffies(MESH_FAST_TX_CACHE_TIMEOUT);
603 struct mesh_tx_cache *cache;
604 struct ieee80211_mesh_fast_tx *entry;
605 struct hlist_node *n;
606
607 cache = &sdata->u.mesh.tx_cache;
608 if (atomic_read(v: &cache->rht.nelems) < MESH_FAST_TX_CACHE_THRESHOLD_SIZE)
609 return;
610
611 spin_lock_bh(lock: &cache->walk_lock);
612 hlist_for_each_entry_safe(entry, n, &cache->walk_head, walk_list)
613 if (!time_is_after_jiffies(entry->timestamp + timeout))
614 mesh_fast_tx_entry_free(cache, entry);
615 spin_unlock_bh(lock: &cache->walk_lock);
616}
617
618void mesh_fast_tx_flush_mpath(struct mesh_path *mpath)
619{
620 struct ieee80211_sub_if_data *sdata = mpath->sdata;
621 struct mesh_tx_cache *cache = &sdata->u.mesh.tx_cache;
622 struct ieee80211_mesh_fast_tx *entry;
623 struct hlist_node *n;
624
625 cache = &sdata->u.mesh.tx_cache;
626 spin_lock_bh(lock: &cache->walk_lock);
627 hlist_for_each_entry_safe(entry, n, &cache->walk_head, walk_list)
628 if (entry->mpath == mpath)
629 mesh_fast_tx_entry_free(cache, entry);
630 spin_unlock_bh(lock: &cache->walk_lock);
631}
632
633void mesh_fast_tx_flush_sta(struct ieee80211_sub_if_data *sdata,
634 struct sta_info *sta)
635{
636 struct mesh_tx_cache *cache = &sdata->u.mesh.tx_cache;
637 struct ieee80211_mesh_fast_tx *entry;
638 struct hlist_node *n;
639
640 cache = &sdata->u.mesh.tx_cache;
641 spin_lock_bh(lock: &cache->walk_lock);
642 hlist_for_each_entry_safe(entry, n, &cache->walk_head, walk_list)
643 if (rcu_access_pointer(entry->mpath->next_hop) == sta)
644 mesh_fast_tx_entry_free(cache, entry);
645 spin_unlock_bh(lock: &cache->walk_lock);
646}
647
648void mesh_fast_tx_flush_addr(struct ieee80211_sub_if_data *sdata,
649 const u8 *addr)
650{
651 struct mesh_tx_cache *cache = &sdata->u.mesh.tx_cache;
652 struct ieee80211_mesh_fast_tx *entry;
653
654 cache = &sdata->u.mesh.tx_cache;
655 spin_lock_bh(lock: &cache->walk_lock);
656 entry = rhashtable_lookup_fast(ht: &cache->rht, key: addr, params: fast_tx_rht_params);
657 if (entry)
658 mesh_fast_tx_entry_free(cache, entry);
659 spin_unlock_bh(lock: &cache->walk_lock);
660}
661
662/**
663 * mesh_path_add - allocate and add a new path to the mesh path table
664 * @dst: destination address of the path (ETH_ALEN length)
665 * @sdata: local subif
666 *
667 * Returns: 0 on success
668 *
669 * State: the initial state of the new path is set to 0
670 */
671struct mesh_path *mesh_path_add(struct ieee80211_sub_if_data *sdata,
672 const u8 *dst)
673{
674 struct mesh_table *tbl;
675 struct mesh_path *mpath, *new_mpath;
676
677 if (ether_addr_equal(addr1: dst, addr2: sdata->vif.addr))
678 /* never add ourselves as neighbours */
679 return ERR_PTR(error: -ENOTSUPP);
680
681 if (is_multicast_ether_addr(addr: dst))
682 return ERR_PTR(error: -ENOTSUPP);
683
684 if (atomic_add_unless(v: &sdata->u.mesh.mpaths, a: 1, MESH_MAX_MPATHS) == 0)
685 return ERR_PTR(error: -ENOSPC);
686
687 new_mpath = mesh_path_new(sdata, dst, GFP_ATOMIC);
688 if (!new_mpath)
689 return ERR_PTR(error: -ENOMEM);
690
691 tbl = &sdata->u.mesh.mesh_paths;
692 spin_lock_bh(lock: &tbl->walk_lock);
693 mpath = rhashtable_lookup_get_insert_fast(ht: &tbl->rhead,
694 obj: &new_mpath->rhash,
695 params: mesh_rht_params);
696 if (!mpath)
697 hlist_add_head(n: &new_mpath->walk_list, h: &tbl->walk_head);
698 spin_unlock_bh(lock: &tbl->walk_lock);
699
700 if (mpath) {
701 kfree(objp: new_mpath);
702
703 if (IS_ERR(ptr: mpath))
704 return mpath;
705
706 new_mpath = mpath;
707 }
708
709 sdata->u.mesh.mesh_paths_generation++;
710 return new_mpath;
711}
712
713int mpp_path_add(struct ieee80211_sub_if_data *sdata,
714 const u8 *dst, const u8 *mpp)
715{
716 struct mesh_table *tbl;
717 struct mesh_path *new_mpath;
718 int ret;
719
720 if (ether_addr_equal(addr1: dst, addr2: sdata->vif.addr))
721 /* never add ourselves as neighbours */
722 return -ENOTSUPP;
723
724 if (is_multicast_ether_addr(addr: dst))
725 return -ENOTSUPP;
726
727 new_mpath = mesh_path_new(sdata, dst, GFP_ATOMIC);
728
729 if (!new_mpath)
730 return -ENOMEM;
731
732 memcpy(new_mpath->mpp, mpp, ETH_ALEN);
733 tbl = &sdata->u.mesh.mpp_paths;
734
735 spin_lock_bh(lock: &tbl->walk_lock);
736 ret = rhashtable_lookup_insert_fast(ht: &tbl->rhead,
737 obj: &new_mpath->rhash,
738 params: mesh_rht_params);
739 if (!ret)
740 hlist_add_head_rcu(n: &new_mpath->walk_list, h: &tbl->walk_head);
741 spin_unlock_bh(lock: &tbl->walk_lock);
742
743 if (ret)
744 kfree(objp: new_mpath);
745 else
746 mesh_fast_tx_flush_addr(sdata, addr: dst);
747
748 sdata->u.mesh.mpp_paths_generation++;
749 return ret;
750}
751
752
753/**
754 * mesh_plink_broken - deactivates paths and sends perr when a link breaks
755 *
756 * @sta: broken peer link
757 *
758 * This function must be called from the rate control algorithm if enough
759 * delivery errors suggest that a peer link is no longer usable.
760 */
761void mesh_plink_broken(struct sta_info *sta)
762{
763 struct ieee80211_sub_if_data *sdata = sta->sdata;
764 struct mesh_table *tbl = &sdata->u.mesh.mesh_paths;
765 static const u8 bcast[ETH_ALEN] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
766 struct mesh_path *mpath;
767
768 rcu_read_lock();
769 hlist_for_each_entry_rcu(mpath, &tbl->walk_head, walk_list) {
770 if (rcu_access_pointer(mpath->next_hop) == sta &&
771 mpath->flags & MESH_PATH_ACTIVE &&
772 !(mpath->flags & MESH_PATH_FIXED)) {
773 spin_lock_bh(lock: &mpath->state_lock);
774 mpath->flags &= ~MESH_PATH_ACTIVE;
775 ++mpath->sn;
776 spin_unlock_bh(lock: &mpath->state_lock);
777 mesh_path_error_tx(sdata,
778 ttl: sdata->u.mesh.mshcfg.element_ttl,
779 target: mpath->dst, target_sn: mpath->sn,
780 target_rcode: WLAN_REASON_MESH_PATH_DEST_UNREACHABLE, ra: bcast);
781 }
782 }
783 rcu_read_unlock();
784}
785
786static void mesh_path_free_rcu(struct mesh_table *tbl,
787 struct mesh_path *mpath)
788{
789 struct ieee80211_sub_if_data *sdata = mpath->sdata;
790
791 spin_lock_bh(lock: &mpath->state_lock);
792 mpath->flags |= MESH_PATH_RESOLVING | MESH_PATH_DELETED;
793 mesh_gate_del(tbl, mpath);
794 spin_unlock_bh(lock: &mpath->state_lock);
795 timer_shutdown_sync(timer: &mpath->timer);
796 atomic_dec(v: &sdata->u.mesh.mpaths);
797 atomic_dec(v: &tbl->entries);
798 mesh_path_flush_pending(mpath);
799 kfree_rcu(mpath, rcu);
800}
801
802static void __mesh_path_del(struct mesh_table *tbl, struct mesh_path *mpath)
803{
804 hlist_del_rcu(n: &mpath->walk_list);
805 rhashtable_remove_fast(ht: &tbl->rhead, obj: &mpath->rhash, params: mesh_rht_params);
806 if (tbl == &mpath->sdata->u.mesh.mpp_paths)
807 mesh_fast_tx_flush_addr(sdata: mpath->sdata, addr: mpath->dst);
808 else
809 mesh_fast_tx_flush_mpath(mpath);
810 mesh_path_free_rcu(tbl, mpath);
811}
812
813/**
814 * mesh_path_flush_by_nexthop - Deletes mesh paths if their next hop matches
815 *
816 * @sta: mesh peer to match
817 *
818 * RCU notes: this function is called when a mesh plink transitions from
819 * PLINK_ESTAB to any other state, since PLINK_ESTAB state is the only one that
820 * allows path creation. This will happen before the sta can be freed (because
821 * sta_info_destroy() calls this) so any reader in a rcu read block will be
822 * protected against the plink disappearing.
823 */
824void mesh_path_flush_by_nexthop(struct sta_info *sta)
825{
826 struct ieee80211_sub_if_data *sdata = sta->sdata;
827 struct mesh_table *tbl = &sdata->u.mesh.mesh_paths;
828 struct mesh_path *mpath;
829 struct hlist_node *n;
830
831 spin_lock_bh(lock: &tbl->walk_lock);
832 hlist_for_each_entry_safe(mpath, n, &tbl->walk_head, walk_list) {
833 if (rcu_access_pointer(mpath->next_hop) == sta)
834 __mesh_path_del(tbl, mpath);
835 }
836 spin_unlock_bh(lock: &tbl->walk_lock);
837}
838
839static void mpp_flush_by_proxy(struct ieee80211_sub_if_data *sdata,
840 const u8 *proxy)
841{
842 struct mesh_table *tbl = &sdata->u.mesh.mpp_paths;
843 struct mesh_path *mpath;
844 struct hlist_node *n;
845
846 spin_lock_bh(lock: &tbl->walk_lock);
847 hlist_for_each_entry_safe(mpath, n, &tbl->walk_head, walk_list) {
848 if (ether_addr_equal(addr1: mpath->mpp, addr2: proxy))
849 __mesh_path_del(tbl, mpath);
850 }
851 spin_unlock_bh(lock: &tbl->walk_lock);
852}
853
854static void table_flush_by_iface(struct mesh_table *tbl)
855{
856 struct mesh_path *mpath;
857 struct hlist_node *n;
858
859 spin_lock_bh(lock: &tbl->walk_lock);
860 hlist_for_each_entry_safe(mpath, n, &tbl->walk_head, walk_list) {
861 __mesh_path_del(tbl, mpath);
862 }
863 spin_unlock_bh(lock: &tbl->walk_lock);
864}
865
866/**
867 * mesh_path_flush_by_iface - Deletes all mesh paths associated with a given iface
868 *
869 * @sdata: interface data to match
870 *
871 * This function deletes both mesh paths as well as mesh portal paths.
872 */
873void mesh_path_flush_by_iface(struct ieee80211_sub_if_data *sdata)
874{
875 table_flush_by_iface(tbl: &sdata->u.mesh.mesh_paths);
876 table_flush_by_iface(tbl: &sdata->u.mesh.mpp_paths);
877}
878
879/**
880 * table_path_del - delete a path from the mesh or mpp table
881 *
882 * @tbl: mesh or mpp path table
883 * @sdata: local subif
884 * @addr: dst address (ETH_ALEN length)
885 *
886 * Returns: 0 if successful
887 */
888static int table_path_del(struct mesh_table *tbl,
889 struct ieee80211_sub_if_data *sdata,
890 const u8 *addr)
891{
892 struct mesh_path *mpath;
893
894 spin_lock_bh(lock: &tbl->walk_lock);
895 mpath = rhashtable_lookup_fast(ht: &tbl->rhead, key: addr, params: mesh_rht_params);
896 if (!mpath) {
897 spin_unlock_bh(lock: &tbl->walk_lock);
898 return -ENXIO;
899 }
900
901 __mesh_path_del(tbl, mpath);
902 spin_unlock_bh(lock: &tbl->walk_lock);
903 return 0;
904}
905
906
907/**
908 * mesh_path_del - delete a mesh path from the table
909 *
910 * @addr: dst address (ETH_ALEN length)
911 * @sdata: local subif
912 *
913 * Returns: 0 if successful
914 */
915int mesh_path_del(struct ieee80211_sub_if_data *sdata, const u8 *addr)
916{
917 int err;
918
919 /* flush relevant mpp entries first */
920 mpp_flush_by_proxy(sdata, proxy: addr);
921
922 err = table_path_del(tbl: &sdata->u.mesh.mesh_paths, sdata, addr);
923 sdata->u.mesh.mesh_paths_generation++;
924 return err;
925}
926
927/**
928 * mesh_path_tx_pending - sends pending frames in a mesh path queue
929 *
930 * @mpath: mesh path to activate
931 *
932 * Locking: the state_lock of the mpath structure must NOT be held when calling
933 * this function.
934 */
935void mesh_path_tx_pending(struct mesh_path *mpath)
936{
937 if (mpath->flags & MESH_PATH_ACTIVE)
938 ieee80211_add_pending_skbs(local: mpath->sdata->local,
939 skbs: &mpath->frame_queue);
940}
941
942/**
943 * mesh_path_send_to_gates - sends pending frames to all known mesh gates
944 *
945 * @mpath: mesh path whose queue will be emptied
946 *
947 * If there is only one gate, the frames are transferred from the failed mpath
948 * queue to that gate's queue. If there are more than one gates, the frames
949 * are copied from each gate to the next. After frames are copied, the
950 * mpath queues are emptied onto the transmission queue.
951 *
952 * Returns: 0 on success, -EHOSTUNREACH
953 */
954int mesh_path_send_to_gates(struct mesh_path *mpath)
955{
956 struct ieee80211_sub_if_data *sdata = mpath->sdata;
957 struct mesh_table *tbl;
958 struct mesh_path *from_mpath = mpath;
959 struct mesh_path *gate;
960 bool copy = false;
961
962 tbl = &sdata->u.mesh.mesh_paths;
963
964 rcu_read_lock();
965 hlist_for_each_entry_rcu(gate, &tbl->known_gates, gate_list) {
966 if (gate->flags & MESH_PATH_ACTIVE) {
967 mpath_dbg(sdata, "Forwarding to %pM\n", gate->dst);
968 mesh_path_move_to_queue(gate_mpath: gate, from_mpath, copy);
969 from_mpath = gate;
970 copy = true;
971 } else {
972 mpath_dbg(sdata,
973 "Not forwarding to %pM (flags %#x)\n",
974 gate->dst, gate->flags);
975 }
976 }
977
978 hlist_for_each_entry_rcu(gate, &tbl->known_gates, gate_list) {
979 mpath_dbg(sdata, "Sending to %pM\n", gate->dst);
980 mesh_path_tx_pending(mpath: gate);
981 }
982 rcu_read_unlock();
983
984 return (from_mpath == mpath) ? -EHOSTUNREACH : 0;
985}
986
987/**
988 * mesh_path_discard_frame - discard a frame whose path could not be resolved
989 *
990 * @skb: frame to discard
991 * @sdata: network subif the frame was to be sent through
992 *
993 * Locking: the function must me called within a rcu_read_lock region
994 */
995void mesh_path_discard_frame(struct ieee80211_sub_if_data *sdata,
996 struct sk_buff *skb)
997{
998 ieee80211_free_txskb(hw: &sdata->local->hw, skb);
999 sdata->u.mesh.mshstats.dropped_frames_no_route++;
1000}
1001
1002/**
1003 * mesh_path_flush_pending - free the pending queue of a mesh path
1004 *
1005 * @mpath: mesh path whose queue has to be freed
1006 *
1007 * Locking: the function must me called within a rcu_read_lock region
1008 */
1009void mesh_path_flush_pending(struct mesh_path *mpath)
1010{
1011 struct sk_buff *skb;
1012
1013 while ((skb = skb_dequeue(list: &mpath->frame_queue)) != NULL)
1014 mesh_path_discard_frame(sdata: mpath->sdata, skb);
1015}
1016
1017/**
1018 * mesh_path_fix_nexthop - force a specific next hop for a mesh path
1019 *
1020 * @mpath: the mesh path to modify
1021 * @next_hop: the next hop to force
1022 *
1023 * Locking: this function must be called holding mpath->state_lock
1024 */
1025void mesh_path_fix_nexthop(struct mesh_path *mpath, struct sta_info *next_hop)
1026{
1027 spin_lock_bh(lock: &mpath->state_lock);
1028 mesh_path_assign_nexthop(mpath, sta: next_hop);
1029 mpath->sn = 0xffff;
1030 mpath->metric = 0;
1031 mpath->hop_count = 0;
1032 mpath->exp_time = 0;
1033 mpath->flags = MESH_PATH_FIXED | MESH_PATH_SN_VALID;
1034 mesh_path_activate(mpath);
1035 mesh_fast_tx_flush_mpath(mpath);
1036 spin_unlock_bh(lock: &mpath->state_lock);
1037 ewma_mesh_fail_avg_init(e: &next_hop->mesh->fail_avg);
1038 /* init it at a low value - 0 start is tricky */
1039 ewma_mesh_fail_avg_add(e: &next_hop->mesh->fail_avg, val: 1);
1040 mesh_path_tx_pending(mpath);
1041}
1042
1043void mesh_pathtbl_init(struct ieee80211_sub_if_data *sdata)
1044{
1045 mesh_table_init(tbl: &sdata->u.mesh.mesh_paths);
1046 mesh_table_init(tbl: &sdata->u.mesh.mpp_paths);
1047 mesh_fast_tx_init(sdata);
1048}
1049
1050static
1051void mesh_path_tbl_expire(struct ieee80211_sub_if_data *sdata,
1052 struct mesh_table *tbl)
1053{
1054 struct mesh_path *mpath;
1055 struct hlist_node *n;
1056
1057 spin_lock_bh(lock: &tbl->walk_lock);
1058 hlist_for_each_entry_safe(mpath, n, &tbl->walk_head, walk_list) {
1059 if ((!(mpath->flags & MESH_PATH_RESOLVING)) &&
1060 (!(mpath->flags & MESH_PATH_FIXED)) &&
1061 time_after(jiffies, mpath->exp_time + MESH_PATH_EXPIRE))
1062 __mesh_path_del(tbl, mpath);
1063 }
1064 spin_unlock_bh(lock: &tbl->walk_lock);
1065}
1066
1067void mesh_path_expire(struct ieee80211_sub_if_data *sdata)
1068{
1069 mesh_path_tbl_expire(sdata, tbl: &sdata->u.mesh.mesh_paths);
1070 mesh_path_tbl_expire(sdata, tbl: &sdata->u.mesh.mpp_paths);
1071}
1072
1073void mesh_pathtbl_unregister(struct ieee80211_sub_if_data *sdata)
1074{
1075 mesh_fast_tx_deinit(sdata);
1076 mesh_table_free(tbl: &sdata->u.mesh.mesh_paths);
1077 mesh_table_free(tbl: &sdata->u.mesh.mpp_paths);
1078}
1079

source code of linux/net/mac80211/mesh_pathtbl.c