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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 <[email protected]>
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(get_unaligned((u32 *)((u8 *)addr + 2)), 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 = sizeof_field(struct ieee80211_mesh_fast_tx, key),
41 .key_offset = offsetof(struct ieee80211_mesh_fast_tx, 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(&cache->rht,
59 __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(&cache->rht, &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(&tbl->entries, 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(&tbl->rhead,
104 mesh_path_rht_free, 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(sta->sdata, sta, hdr);
129 }
130
131 spin_unlock_irqrestore(&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(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, 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(&failq);
205
206 spin_lock_irqsave(&from_mpath->frame_queue.lock, flags);
207 skb_queue_splice_init(&from_mpath->frame_queue, &failq);
208 spin_unlock_irqrestore(&from_mpath->frame_queue.lock, flags);
209
210 skb_queue_walk_safe(&failq, fskb, tmp) {
211 if (skb_queue_len(&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(fskb, GFP_ATOMIC);
218 if (WARN_ON(!skb))
219 break;
220
221 prepare_for_gate(skb, gate_mpath->dst, gate_mpath);
222 skb_queue_tail(&gate_mpath->frame_queue, skb);
223
224 if (copy)
225 continue;
226
227 __skb_unlink(fskb, &failq);
228 kfree_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(&failq, &from_mpath->frame_queue);
239 spin_unlock_irqrestore(&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(&tbl->rhead, dst, mesh_rht_params);
249
250 if (mpath && mpath_expired(mpath)) {
251 spin_lock_bh(&mpath->state_lock);
252 mpath->flags &= ~MESH_PATH_ACTIVE;
253 spin_unlock_bh(&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(&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(&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(&mpath->state_lock);
295 mpath->flags &= ~MESH_PATH_ACTIVE;
296 spin_unlock_bh(&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 * @sdata: local subif, or NULL for all entries
304 * @idx: index
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(&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 * @sdata: local subif, or NULL for all entries
319 * @idx: index
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(&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(&mpath->state_lock);
346 if (mpath->is_gate) {
347 err = -EEXIST;
348 spin_unlock_bh(&mpath->state_lock);
349 goto err_rcu;
350 }
351 mpath->is_gate = true;
352 mpath->sdata->u.mesh.num_gates++;
353
354 spin_lock(&tbl->gates_lock);
355 hlist_add_head_rcu(&mpath->gate_list, &tbl->known_gates);
356 spin_unlock(&tbl->gates_lock);
357
358 spin_unlock_bh(&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(&tbl->gates_lock);
382 hlist_del_rcu(&mpath->gate_list);
383 mpath->sdata->u.mesh.num_gates--;
384 spin_unlock_bh(&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_obj(struct mesh_path, gfp_flags);
409 if (!new_mpath)
410 return NULL;
411
412 memcpy(new_mpath->dst, dst, ETH_ALEN);
413 eth_broadcast_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(&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(&entry->walk_list);
429 rhashtable_remove_fast(&cache->rht, &entry->rhash, 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,
435 struct ieee80211_mesh_fast_tx_key *key)
436{
437 struct ieee80211_mesh_fast_tx *entry;
438 struct mesh_tx_cache *cache;
439
440 cache = &sdata->u.mesh.tx_cache;
441 entry = rhashtable_lookup(&cache->rht, key, fast_tx_rht_params);
442 if (!entry)
443 return NULL;
444
445 if (!(entry->mpath->flags & MESH_PATH_ACTIVE) ||
446 mpath_expired(entry->mpath)) {
447 spin_lock_bh(&cache->walk_lock);
448 entry = rhashtable_lookup(&cache->rht, key, fast_tx_rht_params);
449 if (entry)
450 mesh_fast_tx_entry_free(cache, entry);
451 spin_unlock_bh(&cache->walk_lock);
452 return NULL;
453 }
454
455 mesh_path_refresh(sdata, entry->mpath, NULL);
456 if (entry->mppath)
457 entry->mppath->exp_time = jiffies;
458 entry->timestamp = jiffies;
459
460 return entry;
461}
462
463void mesh_fast_tx_cache(struct ieee80211_sub_if_data *sdata,
464 struct sk_buff *skb, struct mesh_path *mpath)
465{
466 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
467 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
468 struct ieee80211_mesh_fast_tx *entry, *prev;
469 struct ieee80211_mesh_fast_tx build = {};
470 struct ieee80211s_hdr *meshhdr;
471 struct mesh_tx_cache *cache;
472 struct ieee80211_key *key;
473 struct mesh_path *mppath;
474 struct sta_info *sta;
475 u8 *qc;
476
477 if (sdata->noack_map ||
478 !ieee80211_is_data_qos(hdr->frame_control))
479 return;
480
481 build.fast_tx.hdr_len = ieee80211_hdrlen(hdr->frame_control);
482 meshhdr = (struct ieee80211s_hdr *)(skb->data + build.fast_tx.hdr_len);
483 build.hdrlen = ieee80211_get_mesh_hdrlen(meshhdr);
484
485 cache = &sdata->u.mesh.tx_cache;
486 if (atomic_read(&cache->rht.nelems) >= MESH_FAST_TX_CACHE_MAX_SIZE)
487 return;
488
489 sta = rcu_dereference(mpath->next_hop);
490 if (!sta)
491 return;
492
493 build.key.type = MESH_FAST_TX_TYPE_LOCAL;
494 if ((meshhdr->flags & MESH_FLAGS_AE) == MESH_FLAGS_AE_A5_A6) {
495 /* This is required to keep the mppath alive */
496 mppath = mpp_path_lookup(sdata, meshhdr->eaddr1);
497 if (!mppath)
498 return;
499 build.mppath = mppath;
500 if (!ether_addr_equal(meshhdr->eaddr2, sdata->vif.addr))
501 build.key.type = MESH_FAST_TX_TYPE_PROXIED;
502 } else if (ieee80211_has_a4(hdr->frame_control)) {
503 mppath = mpath;
504 } else {
505 return;
506 }
507
508 if (!ether_addr_equal(hdr->addr4, sdata->vif.addr))
509 build.key.type = MESH_FAST_TX_TYPE_FORWARDED;
510
511 /* rate limit, in case fast xmit can't be enabled */
512 if (mppath->fast_tx_check == jiffies)
513 return;
514
515 mppath->fast_tx_check = jiffies;
516
517 /*
518 * Same use of the sta lock as in ieee80211_check_fast_xmit, in order
519 * to protect against concurrent sta key updates.
520 */
521 spin_lock_bh(&sta->lock);
522 key = rcu_access_pointer(sta->ptk[sta->ptk_idx]);
523 if (!key)
524 key = rcu_access_pointer(sdata->default_unicast_key);
525 build.fast_tx.key = key;
526
527 if (key) {
528 bool gen_iv, iv_spc;
529
530 gen_iv = key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV;
531 iv_spc = key->conf.flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE;
532
533 if (!(key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) ||
534 (key->flags & KEY_FLAG_TAINTED))
535 goto unlock_sta;
536
537 switch (key->conf.cipher) {
538 case WLAN_CIPHER_SUITE_CCMP:
539 case WLAN_CIPHER_SUITE_CCMP_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_CCMP_HDR_LEN;
544 break;
545 case WLAN_CIPHER_SUITE_GCMP:
546 case WLAN_CIPHER_SUITE_GCMP_256:
547 if (gen_iv)
548 build.fast_tx.pn_offs = build.fast_tx.hdr_len;
549 if (gen_iv || iv_spc)
550 build.fast_tx.hdr_len += IEEE80211_GCMP_HDR_LEN;
551 break;
552 default:
553 goto unlock_sta;
554 }
555 }
556
557 memcpy(build.key.addr, mppath->dst, ETH_ALEN);
558 build.timestamp = jiffies;
559 build.fast_tx.band = info->band;
560 build.fast_tx.da_offs = offsetof(struct ieee80211_hdr, addr3);
561 build.fast_tx.sa_offs = offsetof(struct ieee80211_hdr, addr4);
562 build.mpath = mpath;
563 memcpy(build.hdr, meshhdr, build.hdrlen);
564 memcpy(build.hdr + build.hdrlen, rfc1042_header, sizeof(rfc1042_header));
565 build.hdrlen += sizeof(rfc1042_header);
566 memcpy(build.fast_tx.hdr, hdr, build.fast_tx.hdr_len);
567
568 hdr = (struct ieee80211_hdr *)build.fast_tx.hdr;
569 if (build.fast_tx.key)
570 hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
571
572 qc = ieee80211_get_qos_ctl(hdr);
573 qc[1] |= IEEE80211_QOS_CTL_MESH_CONTROL_PRESENT >> 8;
574
575 entry = kmemdup(&build, sizeof(build), GFP_ATOMIC);
576 if (!entry)
577 goto unlock_sta;
578
579 spin_lock(&cache->walk_lock);
580 if ((READ_ONCE(mpath->flags) & MESH_PATH_DELETED) ||
581 (mppath && (READ_ONCE(mppath->flags) & MESH_PATH_DELETED))) {
582 kfree(entry);
583 goto unlock_cache;
584 }
585
586 prev = rhashtable_lookup_get_insert_fast(&cache->rht,
587 &entry->rhash,
588 fast_tx_rht_params);
589 if (IS_ERR(prev)) {
590 kfree(entry);
591 goto unlock_cache;
592 }
593
594 /*
595 * replace any previous entry in the hash table, in case we're
596 * replacing it with a different type (e.g. mpath -> mpp)
597 */
598 if (unlikely(prev)) {
599 rhashtable_replace_fast(&cache->rht, &prev->rhash,
600 &entry->rhash, fast_tx_rht_params);
601 hlist_del_rcu(&prev->walk_list);
602 kfree_rcu(prev, fast_tx.rcu_head);
603 }
604
605 hlist_add_head(&entry->walk_list, &cache->walk_head);
606
607unlock_cache:
608 spin_unlock(&cache->walk_lock);
609unlock_sta:
610 spin_unlock_bh(&sta->lock);
611}
612
613void mesh_fast_tx_gc(struct ieee80211_sub_if_data *sdata)
614{
615 unsigned long timeout = msecs_to_jiffies(MESH_FAST_TX_CACHE_TIMEOUT);
616 struct mesh_tx_cache *cache = &sdata->u.mesh.tx_cache;
617 struct ieee80211_mesh_fast_tx *entry;
618 struct hlist_node *n;
619
620 if (atomic_read(&cache->rht.nelems) < MESH_FAST_TX_CACHE_THRESHOLD_SIZE)
621 return;
622
623 spin_lock_bh(&cache->walk_lock);
624 hlist_for_each_entry_safe(entry, n, &cache->walk_head, walk_list)
625 if (!time_is_after_jiffies(entry->timestamp + timeout))
626 mesh_fast_tx_entry_free(cache, entry);
627 spin_unlock_bh(&cache->walk_lock);
628}
629
630void mesh_fast_tx_flush_mpath(struct mesh_path *mpath)
631{
632 struct ieee80211_sub_if_data *sdata = mpath->sdata;
633 struct mesh_tx_cache *cache = &sdata->u.mesh.tx_cache;
634 struct ieee80211_mesh_fast_tx *entry;
635 struct hlist_node *n;
636
637 spin_lock_bh(&cache->walk_lock);
638 hlist_for_each_entry_safe(entry, n, &cache->walk_head, walk_list)
639 if (entry->mpath == mpath)
640 mesh_fast_tx_entry_free(cache, entry);
641 spin_unlock_bh(&cache->walk_lock);
642}
643
644void mesh_fast_tx_flush_sta(struct ieee80211_sub_if_data *sdata,
645 struct sta_info *sta)
646{
647 struct mesh_tx_cache *cache = &sdata->u.mesh.tx_cache;
648 struct ieee80211_mesh_fast_tx *entry;
649 struct hlist_node *n;
650
651 spin_lock_bh(&cache->walk_lock);
652 hlist_for_each_entry_safe(entry, n, &cache->walk_head, walk_list)
653 if (rcu_access_pointer(entry->mpath->next_hop) == sta)
654 mesh_fast_tx_entry_free(cache, entry);
655 spin_unlock_bh(&cache->walk_lock);
656}
657
658void mesh_fast_tx_flush_addr(struct ieee80211_sub_if_data *sdata,
659 const u8 *addr)
660{
661 struct mesh_tx_cache *cache = &sdata->u.mesh.tx_cache;
662 struct ieee80211_mesh_fast_tx_key key = {};
663 struct ieee80211_mesh_fast_tx *entry;
664 int i;
665
666 ether_addr_copy(key.addr, addr);
667 spin_lock_bh(&cache->walk_lock);
668 for (i = 0; i < NUM_MESH_FAST_TX_TYPE; i++) {
669 key.type = i;
670 entry = rhashtable_lookup_fast(&cache->rht, &key, fast_tx_rht_params);
671 if (entry)
672 mesh_fast_tx_entry_free(cache, entry);
673 }
674 spin_unlock_bh(&cache->walk_lock);
675}
676
677/**
678 * mesh_path_add - allocate and add a new path to the mesh path table
679 * @sdata: local subif
680 * @dst: destination address of the path (ETH_ALEN length)
681 *
682 * Returns: 0 on success
683 *
684 * State: the initial state of the new path is set to 0
685 */
686struct mesh_path *mesh_path_add(struct ieee80211_sub_if_data *sdata,
687 const u8 *dst)
688{
689 struct mesh_table *tbl;
690 struct mesh_path *mpath, *new_mpath;
691
692 if (ether_addr_equal(dst, sdata->vif.addr))
693 /* never add ourselves as neighbours */
694 return ERR_PTR(-EOPNOTSUPP);
695
696 if (is_multicast_ether_addr(dst))
697 return ERR_PTR(-EOPNOTSUPP);
698
699 if (atomic_add_unless(&sdata->u.mesh.mpaths, 1, MESH_MAX_MPATHS) == 0)
700 return ERR_PTR(-ENOSPC);
701
702 new_mpath = mesh_path_new(sdata, dst, GFP_ATOMIC);
703 if (!new_mpath) {
704 atomic_dec(&sdata->u.mesh.mpaths);
705 return ERR_PTR(-ENOMEM);
706 }
707
708 tbl = &sdata->u.mesh.mesh_paths;
709 spin_lock_bh(&tbl->walk_lock);
710 mpath = rhashtable_lookup_get_insert_fast(&tbl->rhead,
711 &new_mpath->rhash,
712 mesh_rht_params);
713 if (!mpath)
714 hlist_add_head(&new_mpath->walk_list, &tbl->walk_head);
715 spin_unlock_bh(&tbl->walk_lock);
716
717 if (mpath) {
718 kfree(new_mpath);
719 atomic_dec(&sdata->u.mesh.mpaths);
720
721 if (IS_ERR(mpath))
722 return mpath;
723
724 new_mpath = mpath;
725 }
726
727 sdata->u.mesh.mesh_paths_generation++;
728 return new_mpath;
729}
730
731int mpp_path_add(struct ieee80211_sub_if_data *sdata,
732 const u8 *dst, const u8 *mpp)
733{
734 struct mesh_table *tbl;
735 struct mesh_path *new_mpath;
736 int ret;
737
738 if (ether_addr_equal(dst, sdata->vif.addr))
739 /* never add ourselves as neighbours */
740 return -EOPNOTSUPP;
741
742 if (is_multicast_ether_addr(dst))
743 return -EOPNOTSUPP;
744
745 if (!atomic_add_unless(&sdata->u.mesh.mpaths, 1, MESH_MAX_MPATHS))
746 return -ENOSPC;
747
748 new_mpath = mesh_path_new(sdata, dst, GFP_ATOMIC);
749
750 if (!new_mpath) {
751 atomic_dec(&sdata->u.mesh.mpaths);
752 return -ENOMEM;
753 }
754
755 memcpy(new_mpath->mpp, mpp, ETH_ALEN);
756 tbl = &sdata->u.mesh.mpp_paths;
757
758 spin_lock_bh(&tbl->walk_lock);
759 ret = rhashtable_lookup_insert_fast(&tbl->rhead,
760 &new_mpath->rhash,
761 mesh_rht_params);
762 if (!ret)
763 hlist_add_head_rcu(&new_mpath->walk_list, &tbl->walk_head);
764 spin_unlock_bh(&tbl->walk_lock);
765
766 if (ret) {
767 kfree(new_mpath);
768 atomic_dec(&sdata->u.mesh.mpaths);
769 } else {
770 mesh_fast_tx_flush_addr(sdata, dst);
771 }
772
773 sdata->u.mesh.mpp_paths_generation++;
774 return ret;
775}
776
777
778/**
779 * mesh_plink_broken - deactivates paths and sends perr when a link breaks
780 *
781 * @sta: broken peer link
782 *
783 * This function must be called from the rate control algorithm if enough
784 * delivery errors suggest that a peer link is no longer usable.
785 */
786void mesh_plink_broken(struct sta_info *sta)
787{
788 struct ieee80211_sub_if_data *sdata = sta->sdata;
789 struct mesh_table *tbl = &sdata->u.mesh.mesh_paths;
790 static const u8 bcast[ETH_ALEN] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
791 struct mesh_path *mpath;
792
793 rcu_read_lock();
794 hlist_for_each_entry_rcu(mpath, &tbl->walk_head, walk_list) {
795 if (rcu_access_pointer(mpath->next_hop) == sta &&
796 mpath->flags & MESH_PATH_ACTIVE &&
797 !(mpath->flags & MESH_PATH_FIXED)) {
798 spin_lock_bh(&mpath->state_lock);
799 mpath->flags &= ~MESH_PATH_ACTIVE;
800 ++mpath->sn;
801 spin_unlock_bh(&mpath->state_lock);
802 mesh_path_error_tx(sdata,
803 sdata->u.mesh.mshcfg.element_ttl,
804 mpath->dst, mpath->sn,
805 WLAN_REASON_MESH_PATH_DEST_UNREACHABLE, bcast);
806 }
807 }
808 rcu_read_unlock();
809}
810
811static void mesh_path_free_rcu(struct mesh_table *tbl,
812 struct mesh_path *mpath)
813{
814 struct ieee80211_sub_if_data *sdata = mpath->sdata;
815
816 spin_lock_bh(&mpath->state_lock);
817 WRITE_ONCE(mpath->flags,
818 mpath->flags | MESH_PATH_RESOLVING | MESH_PATH_DELETED);
819 mesh_gate_del(tbl, mpath);
820 spin_unlock_bh(&mpath->state_lock);
821 timer_shutdown_sync(&mpath->timer);
822 atomic_dec(&sdata->u.mesh.mpaths);
823 atomic_dec(&tbl->entries);
824 mesh_path_flush_pending(mpath);
825 kfree_rcu(mpath, rcu);
826}
827
828static void __mesh_path_del(struct mesh_table *tbl, struct mesh_path *mpath)
829{
830 hlist_del_rcu(&mpath->walk_list);
831 rhashtable_remove_fast(&tbl->rhead, &mpath->rhash, mesh_rht_params);
832 spin_lock_bh(&mpath->state_lock);
833 WRITE_ONCE(mpath->flags, mpath->flags | MESH_PATH_DELETED);
834 spin_unlock_bh(&mpath->state_lock);
835 if (tbl == &mpath->sdata->u.mesh.mpp_paths)
836 mesh_fast_tx_flush_addr(mpath->sdata, mpath->dst);
837 else
838 mesh_fast_tx_flush_mpath(mpath);
839 mesh_path_free_rcu(tbl, mpath);
840}
841
842/**
843 * mesh_path_flush_by_nexthop - Deletes mesh paths if their next hop matches
844 *
845 * @sta: mesh peer to match
846 *
847 * RCU notes: this function is called when a mesh plink transitions from
848 * PLINK_ESTAB to any other state, since PLINK_ESTAB state is the only one that
849 * allows path creation. This will happen before the sta can be freed (because
850 * sta_info_destroy() calls this) so any reader in a rcu read block will be
851 * protected against the plink disappearing.
852 */
853void mesh_path_flush_by_nexthop(struct sta_info *sta)
854{
855 struct ieee80211_sub_if_data *sdata = sta->sdata;
856 struct mesh_table *tbl = &sdata->u.mesh.mesh_paths;
857 struct mesh_path *mpath;
858 struct hlist_node *n;
859
860 spin_lock_bh(&tbl->walk_lock);
861 hlist_for_each_entry_safe(mpath, n, &tbl->walk_head, walk_list) {
862 if (rcu_access_pointer(mpath->next_hop) == sta)
863 __mesh_path_del(tbl, mpath);
864 }
865 spin_unlock_bh(&tbl->walk_lock);
866}
867
868static void mpp_flush_by_proxy(struct ieee80211_sub_if_data *sdata,
869 const u8 *proxy)
870{
871 struct mesh_table *tbl = &sdata->u.mesh.mpp_paths;
872 struct mesh_path *mpath;
873 struct hlist_node *n;
874
875 spin_lock_bh(&tbl->walk_lock);
876 hlist_for_each_entry_safe(mpath, n, &tbl->walk_head, walk_list) {
877 if (ether_addr_equal(mpath->mpp, proxy))
878 __mesh_path_del(tbl, mpath);
879 }
880 spin_unlock_bh(&tbl->walk_lock);
881}
882
883static void table_flush_by_iface(struct mesh_table *tbl)
884{
885 struct mesh_path *mpath;
886 struct hlist_node *n;
887
888 spin_lock_bh(&tbl->walk_lock);
889 hlist_for_each_entry_safe(mpath, n, &tbl->walk_head, walk_list) {
890 __mesh_path_del(tbl, mpath);
891 }
892 spin_unlock_bh(&tbl->walk_lock);
893}
894
895/**
896 * mesh_path_flush_by_iface - Deletes all mesh paths associated with a given iface
897 *
898 * @sdata: interface data to match
899 *
900 * This function deletes both mesh paths as well as mesh portal paths.
901 */
902void mesh_path_flush_by_iface(struct ieee80211_sub_if_data *sdata)
903{
904 table_flush_by_iface(&sdata->u.mesh.mesh_paths);
905 table_flush_by_iface(&sdata->u.mesh.mpp_paths);
906}
907
908/**
909 * table_path_del - delete a path from the mesh or mpp table
910 *
911 * @tbl: mesh or mpp path table
912 * @sdata: local subif
913 * @addr: dst address (ETH_ALEN length)
914 *
915 * Returns: 0 if successful
916 */
917static int table_path_del(struct mesh_table *tbl,
918 struct ieee80211_sub_if_data *sdata,
919 const u8 *addr)
920{
921 struct mesh_path *mpath;
922
923 spin_lock_bh(&tbl->walk_lock);
924 mpath = rhashtable_lookup_fast(&tbl->rhead, addr, mesh_rht_params);
925 if (!mpath) {
926 spin_unlock_bh(&tbl->walk_lock);
927 return -ENXIO;
928 }
929
930 __mesh_path_del(tbl, mpath);
931 spin_unlock_bh(&tbl->walk_lock);
932 return 0;
933}
934
935
936/**
937 * mesh_path_del - delete a mesh path from the table
938 *
939 * @sdata: local subif
940 * @addr: dst address (ETH_ALEN length)
941 *
942 * Returns: 0 if successful
943 */
944int mesh_path_del(struct ieee80211_sub_if_data *sdata, const u8 *addr)
945{
946 int err;
947
948 /* flush relevant mpp entries first */
949 mpp_flush_by_proxy(sdata, addr);
950
951 err = table_path_del(&sdata->u.mesh.mesh_paths, sdata, addr);
952 sdata->u.mesh.mesh_paths_generation++;
953 return err;
954}
955
956/**
957 * mesh_path_tx_pending - sends pending frames in a mesh path queue
958 *
959 * @mpath: mesh path to activate
960 *
961 * Locking: the state_lock of the mpath structure must NOT be held when calling
962 * this function.
963 */
964void mesh_path_tx_pending(struct mesh_path *mpath)
965{
966 if (mpath->flags & MESH_PATH_ACTIVE)
967 ieee80211_add_pending_skbs(mpath->sdata->local,
968 &mpath->frame_queue);
969}
970
971/**
972 * mesh_path_send_to_gates - sends pending frames to all known mesh gates
973 *
974 * @mpath: mesh path whose queue will be emptied
975 *
976 * If there is only one gate, the frames are transferred from the failed mpath
977 * queue to that gate's queue. If there are more than one gates, the frames
978 * are copied from each gate to the next. After frames are copied, the
979 * mpath queues are emptied onto the transmission queue.
980 *
981 * Returns: 0 on success, -EHOSTUNREACH
982 */
983int mesh_path_send_to_gates(struct mesh_path *mpath)
984{
985 struct ieee80211_sub_if_data *sdata = mpath->sdata;
986 struct mesh_table *tbl;
987 struct mesh_path *from_mpath = mpath;
988 struct mesh_path *gate;
989 bool copy = false;
990
991 tbl = &sdata->u.mesh.mesh_paths;
992
993 rcu_read_lock();
994 hlist_for_each_entry_rcu(gate, &tbl->known_gates, gate_list) {
995 if (gate->flags & MESH_PATH_ACTIVE) {
996 mpath_dbg(sdata, "Forwarding to %pM\n", gate->dst);
997 mesh_path_move_to_queue(gate, from_mpath, copy);
998 from_mpath = gate;
999 copy = true;
1000 } else {
1001 mpath_dbg(sdata,
1002 "Not forwarding to %pM (flags %#x)\n",
1003 gate->dst, gate->flags);
1004 }
1005 }
1006
1007 hlist_for_each_entry_rcu(gate, &tbl->known_gates, gate_list) {
1008 mpath_dbg(sdata, "Sending to %pM\n", gate->dst);
1009 mesh_path_tx_pending(gate);
1010 }
1011 rcu_read_unlock();
1012
1013 return (from_mpath == mpath) ? -EHOSTUNREACH : 0;
1014}
1015
1016/**
1017 * mesh_path_discard_frame - discard a frame whose path could not be resolved
1018 *
1019 * @sdata: network subif the frame was to be sent through
1020 * @skb: frame to discard
1021 *
1022 * Locking: the function must me called within a rcu_read_lock region
1023 */
1024void mesh_path_discard_frame(struct ieee80211_sub_if_data *sdata,
1025 struct sk_buff *skb)
1026{
1027 ieee80211_free_txskb(&sdata->local->hw, skb);
1028 sdata->u.mesh.mshstats.dropped_frames_no_route++;
1029}
1030
1031/**
1032 * mesh_path_flush_pending - free the pending queue of a mesh path
1033 *
1034 * @mpath: mesh path whose queue has to be freed
1035 *
1036 * Locking: the function must me called within a rcu_read_lock region
1037 */
1038void mesh_path_flush_pending(struct mesh_path *mpath)
1039{
1040 struct ieee80211_sub_if_data *sdata = mpath->sdata;
1041 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1042 struct mesh_preq_queue *preq, *tmp;
1043 struct sk_buff *skb;
1044
1045 while ((skb = skb_dequeue(&mpath->frame_queue)) != NULL)
1046 mesh_path_discard_frame(mpath->sdata, skb);
1047
1048 spin_lock_bh(&ifmsh->mesh_preq_queue_lock);
1049 list_for_each_entry_safe(preq, tmp, &ifmsh->preq_queue.list, list) {
1050 if (ether_addr_equal(mpath->dst, preq->dst)) {
1051 list_del(&preq->list);
1052 kfree(preq);
1053 --ifmsh->preq_queue_len;
1054 }
1055 }
1056 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
1057}
1058
1059/**
1060 * mesh_path_fix_nexthop - force a specific next hop for a mesh path
1061 *
1062 * @mpath: the mesh path to modify
1063 * @next_hop: the next hop to force
1064 *
1065 * Locking: this function must be called holding mpath->state_lock
1066 */
1067void mesh_path_fix_nexthop(struct mesh_path *mpath, struct sta_info *next_hop)
1068{
1069 spin_lock_bh(&mpath->state_lock);
1070 mesh_path_assign_nexthop(mpath, next_hop);
1071 mpath->sn = 0xffff;
1072 mpath->metric = 0;
1073 mpath->hop_count = 0;
1074 mpath->exp_time = 0;
1075 mpath->flags = MESH_PATH_FIXED | MESH_PATH_SN_VALID;
1076 mesh_path_activate(mpath);
1077 mesh_fast_tx_flush_mpath(mpath);
1078 spin_unlock_bh(&mpath->state_lock);
1079 ewma_mesh_fail_avg_init(&next_hop->mesh->fail_avg);
1080 /* init it at a low value - 0 start is tricky */
1081 ewma_mesh_fail_avg_add(&next_hop->mesh->fail_avg, 1);
1082 mesh_path_tx_pending(mpath);
1083}
1084
1085void mesh_pathtbl_init(struct ieee80211_sub_if_data *sdata)
1086{
1087 mesh_table_init(&sdata->u.mesh.mesh_paths);
1088 mesh_table_init(&sdata->u.mesh.mpp_paths);
1089 mesh_fast_tx_init(sdata);
1090}
1091
1092static
1093void mesh_path_tbl_expire(struct ieee80211_sub_if_data *sdata,
1094 struct mesh_table *tbl)
1095{
1096 struct mesh_path *mpath;
1097 struct hlist_node *n;
1098
1099 spin_lock_bh(&tbl->walk_lock);
1100 hlist_for_each_entry_safe(mpath, n, &tbl->walk_head, walk_list) {
1101 if ((!(mpath->flags & MESH_PATH_RESOLVING)) &&
1102 (!(mpath->flags & MESH_PATH_FIXED)) &&
1103 time_after(jiffies, mpath->exp_time + MESH_PATH_EXPIRE))
1104 __mesh_path_del(tbl, mpath);
1105 }
1106 spin_unlock_bh(&tbl->walk_lock);
1107}
1108
1109void mesh_path_expire(struct ieee80211_sub_if_data *sdata)
1110{
1111 mesh_path_tbl_expire(sdata, &sdata->u.mesh.mesh_paths);
1112 mesh_path_tbl_expire(sdata, &sdata->u.mesh.mpp_paths);
1113}
1114
1115void mesh_pathtbl_unregister(struct ieee80211_sub_if_data *sdata)
1116{
1117 mesh_fast_tx_deinit(sdata);
1118 mesh_table_free(&sdata->u.mesh.mesh_paths);
1119 mesh_table_free(&sdata->u.mesh.mpp_paths);
1120}