1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (C) 2007-2019  B.A.T.M.A.N. contributors:
3  *
4  * Marek Lindner, Simon Wunderlich, Antonio Quartulli
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of version 2 of the GNU General Public
8  * License as published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope that it will be useful, but
11  * WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13  * General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program; if not, see <http://www.gnu.org/licenses/>.
17  */
18 
19 #include "translation-table.h"
20 #include "main.h"
21 
22 #include <linux/atomic.h>
23 #include <linux/bitops.h>
24 #include <linux/build_bug.h>
25 #include <linux/byteorder/generic.h>
26 #include <linux/cache.h>
27 #include <linux/compiler.h>
28 #include <linux/crc32c.h>
29 #include <linux/errno.h>
30 #include <linux/etherdevice.h>
31 #include <linux/gfp.h>
32 #include <linux/if_ether.h>
33 #include <linux/init.h>
34 #include <linux/jhash.h>
35 #include <linux/jiffies.h>
36 #include <linux/kernel.h>
37 #include <linux/kref.h>
38 #include <linux/list.h>
39 #include <linux/lockdep.h>
40 #include <linux/net.h>
41 #include <linux/netdevice.h>
42 #include <linux/netlink.h>
43 #include <linux/rculist.h>
44 #include <linux/rcupdate.h>
45 #include <linux/seq_file.h>
46 #include <linux/skbuff.h>
47 #include <linux/slab.h>
48 #include <linux/spinlock.h>
49 #include <linux/stddef.h>
50 #include <linux/string.h>
51 #include <linux/workqueue.h>
52 #include <net/genetlink.h>
53 #include <net/netlink.h>
54 #include <net/sock.h>
55 #include <uapi/linux/batadv_packet.h>
56 #include <uapi/linux/batman_adv.h>
57 
58 #include "bridge_loop_avoidance.h"
59 #include "hard-interface.h"
60 #include "hash.h"
61 #include "log.h"
62 #include "netlink.h"
63 #include "originator.h"
64 #include "soft-interface.h"
65 #include "tvlv.h"
66 
67 static struct kmem_cache *batadv_tl_cache __read_mostly;
68 static struct kmem_cache *batadv_tg_cache __read_mostly;
69 static struct kmem_cache *batadv_tt_orig_cache __read_mostly;
70 static struct kmem_cache *batadv_tt_change_cache __read_mostly;
71 static struct kmem_cache *batadv_tt_req_cache __read_mostly;
72 static struct kmem_cache *batadv_tt_roam_cache __read_mostly;
73 
74 /* hash class keys */
75 static struct lock_class_key batadv_tt_local_hash_lock_class_key;
76 static struct lock_class_key batadv_tt_global_hash_lock_class_key;
77 
78 static void batadv_send_roam_adv(struct batadv_priv *bat_priv, u8 *client,
79 				 unsigned short vid,
80 				 struct batadv_orig_node *orig_node);
81 static void batadv_tt_purge(struct work_struct *work);
82 static void
83 batadv_tt_global_del_orig_list(struct batadv_tt_global_entry *tt_global_entry);
84 static void batadv_tt_global_del(struct batadv_priv *bat_priv,
85 				 struct batadv_orig_node *orig_node,
86 				 const unsigned char *addr,
87 				 unsigned short vid, const char *message,
88 				 bool roaming);
89 
90 /**
91  * batadv_compare_tt() - check if two TT entries are the same
92  * @node: the list element pointer of the first TT entry
93  * @data2: pointer to the tt_common_entry of the second TT entry
94  *
95  * Compare the MAC address and the VLAN ID of the two TT entries and check if
96  * they are the same TT client.
97  * Return: true if the two TT clients are the same, false otherwise
98  */
99 static bool batadv_compare_tt(const struct hlist_node *node, const void *data2)
100 {
101 	const void *data1 = container_of(node, struct batadv_tt_common_entry,
102 					 hash_entry);
103 	const struct batadv_tt_common_entry *tt1 = data1;
104 	const struct batadv_tt_common_entry *tt2 = data2;
105 
106 	return (tt1->vid == tt2->vid) && batadv_compare_eth(data1, data2);
107 }
108 
109 /**
110  * batadv_choose_tt() - return the index of the tt entry in the hash table
111  * @data: pointer to the tt_common_entry object to map
112  * @size: the size of the hash table
113  *
114  * Return: the hash index where the object represented by 'data' should be
115  * stored at.
116  */
117 static inline u32 batadv_choose_tt(const void *data, u32 size)
118 {
119 	struct batadv_tt_common_entry *tt;
120 	u32 hash = 0;
121 
122 	tt = (struct batadv_tt_common_entry *)data;
123 	hash = jhash(&tt->addr, ETH_ALEN, hash);
124 	hash = jhash(&tt->vid, sizeof(tt->vid), hash);
125 
126 	return hash % size;
127 }
128 
129 /**
130  * batadv_tt_hash_find() - look for a client in the given hash table
131  * @hash: the hash table to search
132  * @addr: the mac address of the client to look for
133  * @vid: VLAN identifier
134  *
135  * Return: a pointer to the tt_common struct belonging to the searched client if
136  * found, NULL otherwise.
137  */
138 static struct batadv_tt_common_entry *
139 batadv_tt_hash_find(struct batadv_hashtable *hash, const u8 *addr,
140 		    unsigned short vid)
141 {
142 	struct hlist_head *head;
143 	struct batadv_tt_common_entry to_search, *tt, *tt_tmp = NULL;
144 	u32 index;
145 
146 	if (!hash)
147 		return NULL;
148 
149 	ether_addr_copy(to_search.addr, addr);
150 	to_search.vid = vid;
151 
152 	index = batadv_choose_tt(&to_search, hash->size);
153 	head = &hash->table[index];
154 
155 	rcu_read_lock();
156 	hlist_for_each_entry_rcu(tt, head, hash_entry) {
157 		if (!batadv_compare_eth(tt, addr))
158 			continue;
159 
160 		if (tt->vid != vid)
161 			continue;
162 
163 		if (!kref_get_unless_zero(&tt->refcount))
164 			continue;
165 
166 		tt_tmp = tt;
167 		break;
168 	}
169 	rcu_read_unlock();
170 
171 	return tt_tmp;
172 }
173 
174 /**
175  * batadv_tt_local_hash_find() - search the local table for a given client
176  * @bat_priv: the bat priv with all the soft interface information
177  * @addr: the mac address of the client to look for
178  * @vid: VLAN identifier
179  *
180  * Return: a pointer to the corresponding tt_local_entry struct if the client is
181  * found, NULL otherwise.
182  */
183 static struct batadv_tt_local_entry *
184 batadv_tt_local_hash_find(struct batadv_priv *bat_priv, const u8 *addr,
185 			  unsigned short vid)
186 {
187 	struct batadv_tt_common_entry *tt_common_entry;
188 	struct batadv_tt_local_entry *tt_local_entry = NULL;
189 
190 	tt_common_entry = batadv_tt_hash_find(bat_priv->tt.local_hash, addr,
191 					      vid);
192 	if (tt_common_entry)
193 		tt_local_entry = container_of(tt_common_entry,
194 					      struct batadv_tt_local_entry,
195 					      common);
196 	return tt_local_entry;
197 }
198 
199 /**
200  * batadv_tt_global_hash_find() - search the global table for a given client
201  * @bat_priv: the bat priv with all the soft interface information
202  * @addr: the mac address of the client to look for
203  * @vid: VLAN identifier
204  *
205  * Return: a pointer to the corresponding tt_global_entry struct if the client
206  * is found, NULL otherwise.
207  */
208 static struct batadv_tt_global_entry *
209 batadv_tt_global_hash_find(struct batadv_priv *bat_priv, const u8 *addr,
210 			   unsigned short vid)
211 {
212 	struct batadv_tt_common_entry *tt_common_entry;
213 	struct batadv_tt_global_entry *tt_global_entry = NULL;
214 
215 	tt_common_entry = batadv_tt_hash_find(bat_priv->tt.global_hash, addr,
216 					      vid);
217 	if (tt_common_entry)
218 		tt_global_entry = container_of(tt_common_entry,
219 					       struct batadv_tt_global_entry,
220 					       common);
221 	return tt_global_entry;
222 }
223 
224 /**
225  * batadv_tt_local_entry_free_rcu() - free the tt_local_entry
226  * @rcu: rcu pointer of the tt_local_entry
227  */
228 static void batadv_tt_local_entry_free_rcu(struct rcu_head *rcu)
229 {
230 	struct batadv_tt_local_entry *tt_local_entry;
231 
232 	tt_local_entry = container_of(rcu, struct batadv_tt_local_entry,
233 				      common.rcu);
234 
235 	kmem_cache_free(batadv_tl_cache, tt_local_entry);
236 }
237 
238 /**
239  * batadv_tt_local_entry_release() - release tt_local_entry from lists and queue
240  *  for free after rcu grace period
241  * @ref: kref pointer of the nc_node
242  */
243 static void batadv_tt_local_entry_release(struct kref *ref)
244 {
245 	struct batadv_tt_local_entry *tt_local_entry;
246 
247 	tt_local_entry = container_of(ref, struct batadv_tt_local_entry,
248 				      common.refcount);
249 
250 	batadv_softif_vlan_put(tt_local_entry->vlan);
251 
252 	call_rcu(&tt_local_entry->common.rcu, batadv_tt_local_entry_free_rcu);
253 }
254 
255 /**
256  * batadv_tt_local_entry_put() - decrement the tt_local_entry refcounter and
257  *  possibly release it
258  * @tt_local_entry: tt_local_entry to be free'd
259  */
260 static void
261 batadv_tt_local_entry_put(struct batadv_tt_local_entry *tt_local_entry)
262 {
263 	kref_put(&tt_local_entry->common.refcount,
264 		 batadv_tt_local_entry_release);
265 }
266 
267 /**
268  * batadv_tt_global_entry_free_rcu() - free the tt_global_entry
269  * @rcu: rcu pointer of the tt_global_entry
270  */
271 static void batadv_tt_global_entry_free_rcu(struct rcu_head *rcu)
272 {
273 	struct batadv_tt_global_entry *tt_global_entry;
274 
275 	tt_global_entry = container_of(rcu, struct batadv_tt_global_entry,
276 				       common.rcu);
277 
278 	kmem_cache_free(batadv_tg_cache, tt_global_entry);
279 }
280 
281 /**
282  * batadv_tt_global_entry_release() - release tt_global_entry from lists and
283  *  queue for free after rcu grace period
284  * @ref: kref pointer of the nc_node
285  */
286 static void batadv_tt_global_entry_release(struct kref *ref)
287 {
288 	struct batadv_tt_global_entry *tt_global_entry;
289 
290 	tt_global_entry = container_of(ref, struct batadv_tt_global_entry,
291 				       common.refcount);
292 
293 	batadv_tt_global_del_orig_list(tt_global_entry);
294 
295 	call_rcu(&tt_global_entry->common.rcu, batadv_tt_global_entry_free_rcu);
296 }
297 
298 /**
299  * batadv_tt_global_entry_put() - decrement the tt_global_entry refcounter and
300  *  possibly release it
301  * @tt_global_entry: tt_global_entry to be free'd
302  */
303 static void
304 batadv_tt_global_entry_put(struct batadv_tt_global_entry *tt_global_entry)
305 {
306 	kref_put(&tt_global_entry->common.refcount,
307 		 batadv_tt_global_entry_release);
308 }
309 
310 /**
311  * batadv_tt_global_hash_count() - count the number of orig entries
312  * @bat_priv: the bat priv with all the soft interface information
313  * @addr: the mac address of the client to count entries for
314  * @vid: VLAN identifier
315  *
316  * Return: the number of originators advertising the given address/data
317  * (excluding ourself).
318  */
319 int batadv_tt_global_hash_count(struct batadv_priv *bat_priv,
320 				const u8 *addr, unsigned short vid)
321 {
322 	struct batadv_tt_global_entry *tt_global_entry;
323 	int count;
324 
325 	tt_global_entry = batadv_tt_global_hash_find(bat_priv, addr, vid);
326 	if (!tt_global_entry)
327 		return 0;
328 
329 	count = atomic_read(&tt_global_entry->orig_list_count);
330 	batadv_tt_global_entry_put(tt_global_entry);
331 
332 	return count;
333 }
334 
335 /**
336  * batadv_tt_local_size_mod() - change the size by v of the local table
337  *  identified by vid
338  * @bat_priv: the bat priv with all the soft interface information
339  * @vid: the VLAN identifier of the sub-table to change
340  * @v: the amount to sum to the local table size
341  */
342 static void batadv_tt_local_size_mod(struct batadv_priv *bat_priv,
343 				     unsigned short vid, int v)
344 {
345 	struct batadv_softif_vlan *vlan;
346 
347 	vlan = batadv_softif_vlan_get(bat_priv, vid);
348 	if (!vlan)
349 		return;
350 
351 	atomic_add(v, &vlan->tt.num_entries);
352 
353 	batadv_softif_vlan_put(vlan);
354 }
355 
356 /**
357  * batadv_tt_local_size_inc() - increase by one the local table size for the
358  *  given vid
359  * @bat_priv: the bat priv with all the soft interface information
360  * @vid: the VLAN identifier
361  */
362 static void batadv_tt_local_size_inc(struct batadv_priv *bat_priv,
363 				     unsigned short vid)
364 {
365 	batadv_tt_local_size_mod(bat_priv, vid, 1);
366 }
367 
368 /**
369  * batadv_tt_local_size_dec() - decrease by one the local table size for the
370  *  given vid
371  * @bat_priv: the bat priv with all the soft interface information
372  * @vid: the VLAN identifier
373  */
374 static void batadv_tt_local_size_dec(struct batadv_priv *bat_priv,
375 				     unsigned short vid)
376 {
377 	batadv_tt_local_size_mod(bat_priv, vid, -1);
378 }
379 
380 /**
381  * batadv_tt_global_size_mod() - change the size by v of the global table
382  *  for orig_node identified by vid
383  * @orig_node: the originator for which the table has to be modified
384  * @vid: the VLAN identifier
385  * @v: the amount to sum to the global table size
386  */
387 static void batadv_tt_global_size_mod(struct batadv_orig_node *orig_node,
388 				      unsigned short vid, int v)
389 {
390 	struct batadv_orig_node_vlan *vlan;
391 
392 	vlan = batadv_orig_node_vlan_new(orig_node, vid);
393 	if (!vlan)
394 		return;
395 
396 	if (atomic_add_return(v, &vlan->tt.num_entries) == 0) {
397 		spin_lock_bh(&orig_node->vlan_list_lock);
398 		if (!hlist_unhashed(&vlan->list)) {
399 			hlist_del_init_rcu(&vlan->list);
400 			batadv_orig_node_vlan_put(vlan);
401 		}
402 		spin_unlock_bh(&orig_node->vlan_list_lock);
403 	}
404 
405 	batadv_orig_node_vlan_put(vlan);
406 }
407 
408 /**
409  * batadv_tt_global_size_inc() - increase by one the global table size for the
410  *  given vid
411  * @orig_node: the originator which global table size has to be decreased
412  * @vid: the vlan identifier
413  */
414 static void batadv_tt_global_size_inc(struct batadv_orig_node *orig_node,
415 				      unsigned short vid)
416 {
417 	batadv_tt_global_size_mod(orig_node, vid, 1);
418 }
419 
420 /**
421  * batadv_tt_global_size_dec() - decrease by one the global table size for the
422  *  given vid
423  * @orig_node: the originator which global table size has to be decreased
424  * @vid: the vlan identifier
425  */
426 static void batadv_tt_global_size_dec(struct batadv_orig_node *orig_node,
427 				      unsigned short vid)
428 {
429 	batadv_tt_global_size_mod(orig_node, vid, -1);
430 }
431 
432 /**
433  * batadv_tt_orig_list_entry_free_rcu() - free the orig_entry
434  * @rcu: rcu pointer of the orig_entry
435  */
436 static void batadv_tt_orig_list_entry_free_rcu(struct rcu_head *rcu)
437 {
438 	struct batadv_tt_orig_list_entry *orig_entry;
439 
440 	orig_entry = container_of(rcu, struct batadv_tt_orig_list_entry, rcu);
441 
442 	kmem_cache_free(batadv_tt_orig_cache, orig_entry);
443 }
444 
445 /**
446  * batadv_tt_orig_list_entry_release() - release tt orig entry from lists and
447  *  queue for free after rcu grace period
448  * @ref: kref pointer of the tt orig entry
449  */
450 static void batadv_tt_orig_list_entry_release(struct kref *ref)
451 {
452 	struct batadv_tt_orig_list_entry *orig_entry;
453 
454 	orig_entry = container_of(ref, struct batadv_tt_orig_list_entry,
455 				  refcount);
456 
457 	batadv_orig_node_put(orig_entry->orig_node);
458 	call_rcu(&orig_entry->rcu, batadv_tt_orig_list_entry_free_rcu);
459 }
460 
461 /**
462  * batadv_tt_orig_list_entry_put() - decrement the tt orig entry refcounter and
463  *  possibly release it
464  * @orig_entry: tt orig entry to be free'd
465  */
466 static void
467 batadv_tt_orig_list_entry_put(struct batadv_tt_orig_list_entry *orig_entry)
468 {
469 	kref_put(&orig_entry->refcount, batadv_tt_orig_list_entry_release);
470 }
471 
472 /**
473  * batadv_tt_local_event() - store a local TT event (ADD/DEL)
474  * @bat_priv: the bat priv with all the soft interface information
475  * @tt_local_entry: the TT entry involved in the event
476  * @event_flags: flags to store in the event structure
477  */
478 static void batadv_tt_local_event(struct batadv_priv *bat_priv,
479 				  struct batadv_tt_local_entry *tt_local_entry,
480 				  u8 event_flags)
481 {
482 	struct batadv_tt_change_node *tt_change_node, *entry, *safe;
483 	struct batadv_tt_common_entry *common = &tt_local_entry->common;
484 	u8 flags = common->flags | event_flags;
485 	bool event_removed = false;
486 	bool del_op_requested, del_op_entry;
487 
488 	tt_change_node = kmem_cache_alloc(batadv_tt_change_cache, GFP_ATOMIC);
489 	if (!tt_change_node)
490 		return;
491 
492 	tt_change_node->change.flags = flags;
493 	memset(tt_change_node->change.reserved, 0,
494 	       sizeof(tt_change_node->change.reserved));
495 	ether_addr_copy(tt_change_node->change.addr, common->addr);
496 	tt_change_node->change.vid = htons(common->vid);
497 
498 	del_op_requested = flags & BATADV_TT_CLIENT_DEL;
499 
500 	/* check for ADD+DEL or DEL+ADD events */
501 	spin_lock_bh(&bat_priv->tt.changes_list_lock);
502 	list_for_each_entry_safe(entry, safe, &bat_priv->tt.changes_list,
503 				 list) {
504 		if (!batadv_compare_eth(entry->change.addr, common->addr))
505 			continue;
506 
507 		/* DEL+ADD in the same orig interval have no effect and can be
508 		 * removed to avoid silly behaviour on the receiver side. The
509 		 * other way around (ADD+DEL) can happen in case of roaming of
510 		 * a client still in the NEW state. Roaming of NEW clients is
511 		 * now possible due to automatically recognition of "temporary"
512 		 * clients
513 		 */
514 		del_op_entry = entry->change.flags & BATADV_TT_CLIENT_DEL;
515 		if (!del_op_requested && del_op_entry)
516 			goto del;
517 		if (del_op_requested && !del_op_entry)
518 			goto del;
519 
520 		/* this is a second add in the same originator interval. It
521 		 * means that flags have been changed: update them!
522 		 */
523 		if (!del_op_requested && !del_op_entry)
524 			entry->change.flags = flags;
525 
526 		continue;
527 del:
528 		list_del(&entry->list);
529 		kmem_cache_free(batadv_tt_change_cache, entry);
530 		kmem_cache_free(batadv_tt_change_cache, tt_change_node);
531 		event_removed = true;
532 		goto unlock;
533 	}
534 
535 	/* track the change in the OGMinterval list */
536 	list_add_tail(&tt_change_node->list, &bat_priv->tt.changes_list);
537 
538 unlock:
539 	spin_unlock_bh(&bat_priv->tt.changes_list_lock);
540 
541 	if (event_removed)
542 		atomic_dec(&bat_priv->tt.local_changes);
543 	else
544 		atomic_inc(&bat_priv->tt.local_changes);
545 }
546 
547 /**
548  * batadv_tt_len() - compute length in bytes of given number of tt changes
549  * @changes_num: number of tt changes
550  *
551  * Return: computed length in bytes.
552  */
553 static int batadv_tt_len(int changes_num)
554 {
555 	return changes_num * sizeof(struct batadv_tvlv_tt_change);
556 }
557 
558 /**
559  * batadv_tt_entries() - compute the number of entries fitting in tt_len bytes
560  * @tt_len: available space
561  *
562  * Return: the number of entries.
563  */
564 static u16 batadv_tt_entries(u16 tt_len)
565 {
566 	return tt_len / batadv_tt_len(1);
567 }
568 
569 /**
570  * batadv_tt_local_table_transmit_size() - calculates the local translation
571  *  table size when transmitted over the air
572  * @bat_priv: the bat priv with all the soft interface information
573  *
574  * Return: local translation table size in bytes.
575  */
576 static int batadv_tt_local_table_transmit_size(struct batadv_priv *bat_priv)
577 {
578 	u16 num_vlan = 0;
579 	u16 tt_local_entries = 0;
580 	struct batadv_softif_vlan *vlan;
581 	int hdr_size;
582 
583 	rcu_read_lock();
584 	hlist_for_each_entry_rcu(vlan, &bat_priv->softif_vlan_list, list) {
585 		num_vlan++;
586 		tt_local_entries += atomic_read(&vlan->tt.num_entries);
587 	}
588 	rcu_read_unlock();
589 
590 	/* header size of tvlv encapsulated tt response payload */
591 	hdr_size = sizeof(struct batadv_unicast_tvlv_packet);
592 	hdr_size += sizeof(struct batadv_tvlv_hdr);
593 	hdr_size += sizeof(struct batadv_tvlv_tt_data);
594 	hdr_size += num_vlan * sizeof(struct batadv_tvlv_tt_vlan_data);
595 
596 	return hdr_size + batadv_tt_len(tt_local_entries);
597 }
598 
599 static int batadv_tt_local_init(struct batadv_priv *bat_priv)
600 {
601 	if (bat_priv->tt.local_hash)
602 		return 0;
603 
604 	bat_priv->tt.local_hash = batadv_hash_new(1024);
605 
606 	if (!bat_priv->tt.local_hash)
607 		return -ENOMEM;
608 
609 	batadv_hash_set_lock_class(bat_priv->tt.local_hash,
610 				   &batadv_tt_local_hash_lock_class_key);
611 
612 	return 0;
613 }
614 
615 static void batadv_tt_global_free(struct batadv_priv *bat_priv,
616 				  struct batadv_tt_global_entry *tt_global,
617 				  const char *message)
618 {
619 	batadv_dbg(BATADV_DBG_TT, bat_priv,
620 		   "Deleting global tt entry %pM (vid: %d): %s\n",
621 		   tt_global->common.addr,
622 		   batadv_print_vid(tt_global->common.vid), message);
623 
624 	batadv_hash_remove(bat_priv->tt.global_hash, batadv_compare_tt,
625 			   batadv_choose_tt, &tt_global->common);
626 	batadv_tt_global_entry_put(tt_global);
627 }
628 
629 /**
630  * batadv_tt_local_add() - add a new client to the local table or update an
631  *  existing client
632  * @soft_iface: netdev struct of the mesh interface
633  * @addr: the mac address of the client to add
634  * @vid: VLAN identifier
635  * @ifindex: index of the interface where the client is connected to (useful to
636  *  identify wireless clients)
637  * @mark: the value contained in the skb->mark field of the received packet (if
638  *  any)
639  *
640  * Return: true if the client was successfully added, false otherwise.
641  */
642 bool batadv_tt_local_add(struct net_device *soft_iface, const u8 *addr,
643 			 unsigned short vid, int ifindex, u32 mark)
644 {
645 	struct batadv_priv *bat_priv = netdev_priv(soft_iface);
646 	struct batadv_tt_local_entry *tt_local;
647 	struct batadv_tt_global_entry *tt_global = NULL;
648 	struct net *net = dev_net(soft_iface);
649 	struct batadv_softif_vlan *vlan;
650 	struct net_device *in_dev = NULL;
651 	struct batadv_hard_iface *in_hardif = NULL;
652 	struct hlist_head *head;
653 	struct batadv_tt_orig_list_entry *orig_entry;
654 	int hash_added, table_size, packet_size_max;
655 	bool ret = false;
656 	bool roamed_back = false;
657 	u8 remote_flags;
658 	u32 match_mark;
659 
660 	if (ifindex != BATADV_NULL_IFINDEX)
661 		in_dev = dev_get_by_index(net, ifindex);
662 
663 	if (in_dev)
664 		in_hardif = batadv_hardif_get_by_netdev(in_dev);
665 
666 	tt_local = batadv_tt_local_hash_find(bat_priv, addr, vid);
667 
668 	if (!is_multicast_ether_addr(addr))
669 		tt_global = batadv_tt_global_hash_find(bat_priv, addr, vid);
670 
671 	if (tt_local) {
672 		tt_local->last_seen = jiffies;
673 		if (tt_local->common.flags & BATADV_TT_CLIENT_PENDING) {
674 			batadv_dbg(BATADV_DBG_TT, bat_priv,
675 				   "Re-adding pending client %pM (vid: %d)\n",
676 				   addr, batadv_print_vid(vid));
677 			/* whatever the reason why the PENDING flag was set,
678 			 * this is a client which was enqueued to be removed in
679 			 * this orig_interval. Since it popped up again, the
680 			 * flag can be reset like it was never enqueued
681 			 */
682 			tt_local->common.flags &= ~BATADV_TT_CLIENT_PENDING;
683 			goto add_event;
684 		}
685 
686 		if (tt_local->common.flags & BATADV_TT_CLIENT_ROAM) {
687 			batadv_dbg(BATADV_DBG_TT, bat_priv,
688 				   "Roaming client %pM (vid: %d) came back to its original location\n",
689 				   addr, batadv_print_vid(vid));
690 			/* the ROAM flag is set because this client roamed away
691 			 * and the node got a roaming_advertisement message. Now
692 			 * that the client popped up again at its original
693 			 * location such flag can be unset
694 			 */
695 			tt_local->common.flags &= ~BATADV_TT_CLIENT_ROAM;
696 			roamed_back = true;
697 		}
698 		goto check_roaming;
699 	}
700 
701 	/* Ignore the client if we cannot send it in a full table response. */
702 	table_size = batadv_tt_local_table_transmit_size(bat_priv);
703 	table_size += batadv_tt_len(1);
704 	packet_size_max = atomic_read(&bat_priv->packet_size_max);
705 	if (table_size > packet_size_max) {
706 		net_ratelimited_function(batadv_info, soft_iface,
707 					 "Local translation table size (%i) exceeds maximum packet size (%i); Ignoring new local tt entry: %pM\n",
708 					 table_size, packet_size_max, addr);
709 		goto out;
710 	}
711 
712 	tt_local = kmem_cache_alloc(batadv_tl_cache, GFP_ATOMIC);
713 	if (!tt_local)
714 		goto out;
715 
716 	/* increase the refcounter of the related vlan */
717 	vlan = batadv_softif_vlan_get(bat_priv, vid);
718 	if (!vlan) {
719 		net_ratelimited_function(batadv_info, soft_iface,
720 					 "adding TT local entry %pM to non-existent VLAN %d\n",
721 					 addr, batadv_print_vid(vid));
722 		kmem_cache_free(batadv_tl_cache, tt_local);
723 		tt_local = NULL;
724 		goto out;
725 	}
726 
727 	batadv_dbg(BATADV_DBG_TT, bat_priv,
728 		   "Creating new local tt entry: %pM (vid: %d, ttvn: %d)\n",
729 		   addr, batadv_print_vid(vid),
730 		   (u8)atomic_read(&bat_priv->tt.vn));
731 
732 	ether_addr_copy(tt_local->common.addr, addr);
733 	/* The local entry has to be marked as NEW to avoid to send it in
734 	 * a full table response going out before the next ttvn increment
735 	 * (consistency check)
736 	 */
737 	tt_local->common.flags = BATADV_TT_CLIENT_NEW;
738 	tt_local->common.vid = vid;
739 	if (batadv_is_wifi_hardif(in_hardif))
740 		tt_local->common.flags |= BATADV_TT_CLIENT_WIFI;
741 	kref_init(&tt_local->common.refcount);
742 	tt_local->last_seen = jiffies;
743 	tt_local->common.added_at = tt_local->last_seen;
744 	tt_local->vlan = vlan;
745 
746 	/* the batman interface mac and multicast addresses should never be
747 	 * purged
748 	 */
749 	if (batadv_compare_eth(addr, soft_iface->dev_addr) ||
750 	    is_multicast_ether_addr(addr))
751 		tt_local->common.flags |= BATADV_TT_CLIENT_NOPURGE;
752 
753 	kref_get(&tt_local->common.refcount);
754 	hash_added = batadv_hash_add(bat_priv->tt.local_hash, batadv_compare_tt,
755 				     batadv_choose_tt, &tt_local->common,
756 				     &tt_local->common.hash_entry);
757 
758 	if (unlikely(hash_added != 0)) {
759 		/* remove the reference for the hash */
760 		batadv_tt_local_entry_put(tt_local);
761 		goto out;
762 	}
763 
764 add_event:
765 	batadv_tt_local_event(bat_priv, tt_local, BATADV_NO_FLAGS);
766 
767 check_roaming:
768 	/* Check whether it is a roaming, but don't do anything if the roaming
769 	 * process has already been handled
770 	 */
771 	if (tt_global && !(tt_global->common.flags & BATADV_TT_CLIENT_ROAM)) {
772 		/* These node are probably going to update their tt table */
773 		head = &tt_global->orig_list;
774 		rcu_read_lock();
775 		hlist_for_each_entry_rcu(orig_entry, head, list) {
776 			batadv_send_roam_adv(bat_priv, tt_global->common.addr,
777 					     tt_global->common.vid,
778 					     orig_entry->orig_node);
779 		}
780 		rcu_read_unlock();
781 		if (roamed_back) {
782 			batadv_tt_global_free(bat_priv, tt_global,
783 					      "Roaming canceled");
784 			tt_global = NULL;
785 		} else {
786 			/* The global entry has to be marked as ROAMING and
787 			 * has to be kept for consistency purpose
788 			 */
789 			tt_global->common.flags |= BATADV_TT_CLIENT_ROAM;
790 			tt_global->roam_at = jiffies;
791 		}
792 	}
793 
794 	/* store the current remote flags before altering them. This helps
795 	 * understanding is flags are changing or not
796 	 */
797 	remote_flags = tt_local->common.flags & BATADV_TT_REMOTE_MASK;
798 
799 	if (batadv_is_wifi_hardif(in_hardif))
800 		tt_local->common.flags |= BATADV_TT_CLIENT_WIFI;
801 	else
802 		tt_local->common.flags &= ~BATADV_TT_CLIENT_WIFI;
803 
804 	/* check the mark in the skb: if it's equal to the configured
805 	 * isolation_mark, it means the packet is coming from an isolated
806 	 * non-mesh client
807 	 */
808 	match_mark = (mark & bat_priv->isolation_mark_mask);
809 	if (bat_priv->isolation_mark_mask &&
810 	    match_mark == bat_priv->isolation_mark)
811 		tt_local->common.flags |= BATADV_TT_CLIENT_ISOLA;
812 	else
813 		tt_local->common.flags &= ~BATADV_TT_CLIENT_ISOLA;
814 
815 	/* if any "dynamic" flag has been modified, resend an ADD event for this
816 	 * entry so that all the nodes can get the new flags
817 	 */
818 	if (remote_flags ^ (tt_local->common.flags & BATADV_TT_REMOTE_MASK))
819 		batadv_tt_local_event(bat_priv, tt_local, BATADV_NO_FLAGS);
820 
821 	ret = true;
822 out:
823 	if (in_hardif)
824 		batadv_hardif_put(in_hardif);
825 	if (in_dev)
826 		dev_put(in_dev);
827 	if (tt_local)
828 		batadv_tt_local_entry_put(tt_local);
829 	if (tt_global)
830 		batadv_tt_global_entry_put(tt_global);
831 	return ret;
832 }
833 
834 /**
835  * batadv_tt_prepare_tvlv_global_data() - prepare the TVLV TT header to send
836  *  within a TT Response directed to another node
837  * @orig_node: originator for which the TT data has to be prepared
838  * @tt_data: uninitialised pointer to the address of the TVLV buffer
839  * @tt_change: uninitialised pointer to the address of the area where the TT
840  *  changed can be stored
841  * @tt_len: pointer to the length to reserve to the tt_change. if -1 this
842  *  function reserves the amount of space needed to send the entire global TT
843  *  table. In case of success the value is updated with the real amount of
844  *  reserved bytes
845  * Allocate the needed amount of memory for the entire TT TVLV and write its
846  * header made up by one tvlv_tt_data object and a series of tvlv_tt_vlan_data
847  * objects, one per active VLAN served by the originator node.
848  *
849  * Return: the size of the allocated buffer or 0 in case of failure.
850  */
851 static u16
852 batadv_tt_prepare_tvlv_global_data(struct batadv_orig_node *orig_node,
853 				   struct batadv_tvlv_tt_data **tt_data,
854 				   struct batadv_tvlv_tt_change **tt_change,
855 				   s32 *tt_len)
856 {
857 	u16 num_vlan = 0;
858 	u16 num_entries = 0;
859 	u16 change_offset;
860 	u16 tvlv_len;
861 	struct batadv_tvlv_tt_vlan_data *tt_vlan;
862 	struct batadv_orig_node_vlan *vlan;
863 	u8 *tt_change_ptr;
864 
865 	spin_lock_bh(&orig_node->vlan_list_lock);
866 	hlist_for_each_entry_rcu(vlan, &orig_node->vlan_list, list) {
867 		num_vlan++;
868 		num_entries += atomic_read(&vlan->tt.num_entries);
869 	}
870 
871 	change_offset = sizeof(**tt_data);
872 	change_offset += num_vlan * sizeof(*tt_vlan);
873 
874 	/* if tt_len is negative, allocate the space needed by the full table */
875 	if (*tt_len < 0)
876 		*tt_len = batadv_tt_len(num_entries);
877 
878 	tvlv_len = *tt_len;
879 	tvlv_len += change_offset;
880 
881 	*tt_data = kmalloc(tvlv_len, GFP_ATOMIC);
882 	if (!*tt_data) {
883 		*tt_len = 0;
884 		goto out;
885 	}
886 
887 	(*tt_data)->flags = BATADV_NO_FLAGS;
888 	(*tt_data)->ttvn = atomic_read(&orig_node->last_ttvn);
889 	(*tt_data)->num_vlan = htons(num_vlan);
890 
891 	tt_vlan = (struct batadv_tvlv_tt_vlan_data *)(*tt_data + 1);
892 	hlist_for_each_entry_rcu(vlan, &orig_node->vlan_list, list) {
893 		tt_vlan->vid = htons(vlan->vid);
894 		tt_vlan->crc = htonl(vlan->tt.crc);
895 
896 		tt_vlan++;
897 	}
898 
899 	tt_change_ptr = (u8 *)*tt_data + change_offset;
900 	*tt_change = (struct batadv_tvlv_tt_change *)tt_change_ptr;
901 
902 out:
903 	spin_unlock_bh(&orig_node->vlan_list_lock);
904 	return tvlv_len;
905 }
906 
907 /**
908  * batadv_tt_prepare_tvlv_local_data() - allocate and prepare the TT TVLV for
909  *  this node
910  * @bat_priv: the bat priv with all the soft interface information
911  * @tt_data: uninitialised pointer to the address of the TVLV buffer
912  * @tt_change: uninitialised pointer to the address of the area where the TT
913  *  changes can be stored
914  * @tt_len: pointer to the length to reserve to the tt_change. if -1 this
915  *  function reserves the amount of space needed to send the entire local TT
916  *  table. In case of success the value is updated with the real amount of
917  *  reserved bytes
918  *
919  * Allocate the needed amount of memory for the entire TT TVLV and write its
920  * header made up by one tvlv_tt_data object and a series of tvlv_tt_vlan_data
921  * objects, one per active VLAN.
922  *
923  * Return: the size of the allocated buffer or 0 in case of failure.
924  */
925 static u16
926 batadv_tt_prepare_tvlv_local_data(struct batadv_priv *bat_priv,
927 				  struct batadv_tvlv_tt_data **tt_data,
928 				  struct batadv_tvlv_tt_change **tt_change,
929 				  s32 *tt_len)
930 {
931 	struct batadv_tvlv_tt_vlan_data *tt_vlan;
932 	struct batadv_softif_vlan *vlan;
933 	u16 num_vlan = 0;
934 	u16 vlan_entries = 0;
935 	u16 total_entries = 0;
936 	u16 tvlv_len;
937 	u8 *tt_change_ptr;
938 	int change_offset;
939 
940 	spin_lock_bh(&bat_priv->softif_vlan_list_lock);
941 	hlist_for_each_entry_rcu(vlan, &bat_priv->softif_vlan_list, list) {
942 		vlan_entries = atomic_read(&vlan->tt.num_entries);
943 		if (vlan_entries < 1)
944 			continue;
945 
946 		num_vlan++;
947 		total_entries += vlan_entries;
948 	}
949 
950 	change_offset = sizeof(**tt_data);
951 	change_offset += num_vlan * sizeof(*tt_vlan);
952 
953 	/* if tt_len is negative, allocate the space needed by the full table */
954 	if (*tt_len < 0)
955 		*tt_len = batadv_tt_len(total_entries);
956 
957 	tvlv_len = *tt_len;
958 	tvlv_len += change_offset;
959 
960 	*tt_data = kmalloc(tvlv_len, GFP_ATOMIC);
961 	if (!*tt_data) {
962 		tvlv_len = 0;
963 		goto out;
964 	}
965 
966 	(*tt_data)->flags = BATADV_NO_FLAGS;
967 	(*tt_data)->ttvn = atomic_read(&bat_priv->tt.vn);
968 	(*tt_data)->num_vlan = htons(num_vlan);
969 
970 	tt_vlan = (struct batadv_tvlv_tt_vlan_data *)(*tt_data + 1);
971 	hlist_for_each_entry_rcu(vlan, &bat_priv->softif_vlan_list, list) {
972 		vlan_entries = atomic_read(&vlan->tt.num_entries);
973 		if (vlan_entries < 1)
974 			continue;
975 
976 		tt_vlan->vid = htons(vlan->vid);
977 		tt_vlan->crc = htonl(vlan->tt.crc);
978 
979 		tt_vlan++;
980 	}
981 
982 	tt_change_ptr = (u8 *)*tt_data + change_offset;
983 	*tt_change = (struct batadv_tvlv_tt_change *)tt_change_ptr;
984 
985 out:
986 	spin_unlock_bh(&bat_priv->softif_vlan_list_lock);
987 	return tvlv_len;
988 }
989 
990 /**
991  * batadv_tt_tvlv_container_update() - update the translation table tvlv
992  *  container after local tt changes have been committed
993  * @bat_priv: the bat priv with all the soft interface information
994  */
995 static void batadv_tt_tvlv_container_update(struct batadv_priv *bat_priv)
996 {
997 	struct batadv_tt_change_node *entry, *safe;
998 	struct batadv_tvlv_tt_data *tt_data;
999 	struct batadv_tvlv_tt_change *tt_change;
1000 	int tt_diff_len, tt_change_len = 0;
1001 	int tt_diff_entries_num = 0;
1002 	int tt_diff_entries_count = 0;
1003 	u16 tvlv_len;
1004 
1005 	tt_diff_entries_num = atomic_read(&bat_priv->tt.local_changes);
1006 	tt_diff_len = batadv_tt_len(tt_diff_entries_num);
1007 
1008 	/* if we have too many changes for one packet don't send any
1009 	 * and wait for the tt table request which will be fragmented
1010 	 */
1011 	if (tt_diff_len > bat_priv->soft_iface->mtu)
1012 		tt_diff_len = 0;
1013 
1014 	tvlv_len = batadv_tt_prepare_tvlv_local_data(bat_priv, &tt_data,
1015 						     &tt_change, &tt_diff_len);
1016 	if (!tvlv_len)
1017 		return;
1018 
1019 	tt_data->flags = BATADV_TT_OGM_DIFF;
1020 
1021 	if (tt_diff_len == 0)
1022 		goto container_register;
1023 
1024 	spin_lock_bh(&bat_priv->tt.changes_list_lock);
1025 	atomic_set(&bat_priv->tt.local_changes, 0);
1026 
1027 	list_for_each_entry_safe(entry, safe, &bat_priv->tt.changes_list,
1028 				 list) {
1029 		if (tt_diff_entries_count < tt_diff_entries_num) {
1030 			memcpy(tt_change + tt_diff_entries_count,
1031 			       &entry->change,
1032 			       sizeof(struct batadv_tvlv_tt_change));
1033 			tt_diff_entries_count++;
1034 		}
1035 		list_del(&entry->list);
1036 		kmem_cache_free(batadv_tt_change_cache, entry);
1037 	}
1038 	spin_unlock_bh(&bat_priv->tt.changes_list_lock);
1039 
1040 	/* Keep the buffer for possible tt_request */
1041 	spin_lock_bh(&bat_priv->tt.last_changeset_lock);
1042 	kfree(bat_priv->tt.last_changeset);
1043 	bat_priv->tt.last_changeset_len = 0;
1044 	bat_priv->tt.last_changeset = NULL;
1045 	tt_change_len = batadv_tt_len(tt_diff_entries_count);
1046 	/* check whether this new OGM has no changes due to size problems */
1047 	if (tt_diff_entries_count > 0) {
1048 		/* if kmalloc() fails we will reply with the full table
1049 		 * instead of providing the diff
1050 		 */
1051 		bat_priv->tt.last_changeset = kzalloc(tt_diff_len, GFP_ATOMIC);
1052 		if (bat_priv->tt.last_changeset) {
1053 			memcpy(bat_priv->tt.last_changeset,
1054 			       tt_change, tt_change_len);
1055 			bat_priv->tt.last_changeset_len = tt_diff_len;
1056 		}
1057 	}
1058 	spin_unlock_bh(&bat_priv->tt.last_changeset_lock);
1059 
1060 container_register:
1061 	batadv_tvlv_container_register(bat_priv, BATADV_TVLV_TT, 1, tt_data,
1062 				       tvlv_len);
1063 	kfree(tt_data);
1064 }
1065 
1066 #ifdef CONFIG_BATMAN_ADV_DEBUGFS
1067 
1068 /**
1069  * batadv_tt_local_seq_print_text() - Print the local tt table in a seq file
1070  * @seq: seq file to print on
1071  * @offset: not used
1072  *
1073  * Return: always 0
1074  */
1075 int batadv_tt_local_seq_print_text(struct seq_file *seq, void *offset)
1076 {
1077 	struct net_device *net_dev = (struct net_device *)seq->private;
1078 	struct batadv_priv *bat_priv = netdev_priv(net_dev);
1079 	struct batadv_hashtable *hash = bat_priv->tt.local_hash;
1080 	struct batadv_tt_common_entry *tt_common_entry;
1081 	struct batadv_tt_local_entry *tt_local;
1082 	struct batadv_hard_iface *primary_if;
1083 	struct hlist_head *head;
1084 	u32 i;
1085 	int last_seen_secs;
1086 	int last_seen_msecs;
1087 	unsigned long last_seen_jiffies;
1088 	bool no_purge;
1089 	u16 np_flag = BATADV_TT_CLIENT_NOPURGE;
1090 
1091 	primary_if = batadv_seq_print_text_primary_if_get(seq);
1092 	if (!primary_if)
1093 		goto out;
1094 
1095 	seq_printf(seq,
1096 		   "Locally retrieved addresses (from %s) announced via TT (TTVN: %u):\n",
1097 		   net_dev->name, (u8)atomic_read(&bat_priv->tt.vn));
1098 	seq_puts(seq,
1099 		 "       Client         VID Flags    Last seen (CRC       )\n");
1100 
1101 	for (i = 0; i < hash->size; i++) {
1102 		head = &hash->table[i];
1103 
1104 		rcu_read_lock();
1105 		hlist_for_each_entry_rcu(tt_common_entry,
1106 					 head, hash_entry) {
1107 			tt_local = container_of(tt_common_entry,
1108 						struct batadv_tt_local_entry,
1109 						common);
1110 			last_seen_jiffies = jiffies - tt_local->last_seen;
1111 			last_seen_msecs = jiffies_to_msecs(last_seen_jiffies);
1112 			last_seen_secs = last_seen_msecs / 1000;
1113 			last_seen_msecs = last_seen_msecs % 1000;
1114 
1115 			no_purge = tt_common_entry->flags & np_flag;
1116 			seq_printf(seq,
1117 				   " * %pM %4i [%c%c%c%c%c%c] %3u.%03u   (%#.8x)\n",
1118 				   tt_common_entry->addr,
1119 				   batadv_print_vid(tt_common_entry->vid),
1120 				   ((tt_common_entry->flags &
1121 				     BATADV_TT_CLIENT_ROAM) ? 'R' : '.'),
1122 				   no_purge ? 'P' : '.',
1123 				   ((tt_common_entry->flags &
1124 				     BATADV_TT_CLIENT_NEW) ? 'N' : '.'),
1125 				   ((tt_common_entry->flags &
1126 				     BATADV_TT_CLIENT_PENDING) ? 'X' : '.'),
1127 				   ((tt_common_entry->flags &
1128 				     BATADV_TT_CLIENT_WIFI) ? 'W' : '.'),
1129 				   ((tt_common_entry->flags &
1130 				     BATADV_TT_CLIENT_ISOLA) ? 'I' : '.'),
1131 				   no_purge ? 0 : last_seen_secs,
1132 				   no_purge ? 0 : last_seen_msecs,
1133 				   tt_local->vlan->tt.crc);
1134 		}
1135 		rcu_read_unlock();
1136 	}
1137 out:
1138 	if (primary_if)
1139 		batadv_hardif_put(primary_if);
1140 	return 0;
1141 }
1142 #endif
1143 
1144 /**
1145  * batadv_tt_local_dump_entry() - Dump one TT local entry into a message
1146  * @msg :Netlink message to dump into
1147  * @portid: Port making netlink request
1148  * @cb: Control block containing additional options
1149  * @bat_priv: The bat priv with all the soft interface information
1150  * @common: tt local & tt global common data
1151  *
1152  * Return: Error code, or 0 on success
1153  */
1154 static int
1155 batadv_tt_local_dump_entry(struct sk_buff *msg, u32 portid,
1156 			   struct netlink_callback *cb,
1157 			   struct batadv_priv *bat_priv,
1158 			   struct batadv_tt_common_entry *common)
1159 {
1160 	void *hdr;
1161 	struct batadv_softif_vlan *vlan;
1162 	struct batadv_tt_local_entry *local;
1163 	unsigned int last_seen_msecs;
1164 	u32 crc;
1165 
1166 	local = container_of(common, struct batadv_tt_local_entry, common);
1167 	last_seen_msecs = jiffies_to_msecs(jiffies - local->last_seen);
1168 
1169 	vlan = batadv_softif_vlan_get(bat_priv, common->vid);
1170 	if (!vlan)
1171 		return 0;
1172 
1173 	crc = vlan->tt.crc;
1174 
1175 	batadv_softif_vlan_put(vlan);
1176 
1177 	hdr = genlmsg_put(msg, portid, cb->nlh->nlmsg_seq,
1178 			  &batadv_netlink_family,  NLM_F_MULTI,
1179 			  BATADV_CMD_GET_TRANSTABLE_LOCAL);
1180 	if (!hdr)
1181 		return -ENOBUFS;
1182 
1183 	genl_dump_check_consistent(cb, hdr);
1184 
1185 	if (nla_put(msg, BATADV_ATTR_TT_ADDRESS, ETH_ALEN, common->addr) ||
1186 	    nla_put_u32(msg, BATADV_ATTR_TT_CRC32, crc) ||
1187 	    nla_put_u16(msg, BATADV_ATTR_TT_VID, common->vid) ||
1188 	    nla_put_u32(msg, BATADV_ATTR_TT_FLAGS, common->flags))
1189 		goto nla_put_failure;
1190 
1191 	if (!(common->flags & BATADV_TT_CLIENT_NOPURGE) &&
1192 	    nla_put_u32(msg, BATADV_ATTR_LAST_SEEN_MSECS, last_seen_msecs))
1193 		goto nla_put_failure;
1194 
1195 	genlmsg_end(msg, hdr);
1196 	return 0;
1197 
1198  nla_put_failure:
1199 	genlmsg_cancel(msg, hdr);
1200 	return -EMSGSIZE;
1201 }
1202 
1203 /**
1204  * batadv_tt_local_dump_bucket() - Dump one TT local bucket into a message
1205  * @msg: Netlink message to dump into
1206  * @portid: Port making netlink request
1207  * @cb: Control block containing additional options
1208  * @bat_priv: The bat priv with all the soft interface information
1209  * @hash: hash to dump
1210  * @bucket: bucket index to dump
1211  * @idx_s: Number of entries to skip
1212  *
1213  * Return: Error code, or 0 on success
1214  */
1215 static int
1216 batadv_tt_local_dump_bucket(struct sk_buff *msg, u32 portid,
1217 			    struct netlink_callback *cb,
1218 			    struct batadv_priv *bat_priv,
1219 			    struct batadv_hashtable *hash, unsigned int bucket,
1220 			    int *idx_s)
1221 {
1222 	struct batadv_tt_common_entry *common;
1223 	int idx = 0;
1224 
1225 	spin_lock_bh(&hash->list_locks[bucket]);
1226 	cb->seq = atomic_read(&hash->generation) << 1 | 1;
1227 
1228 	hlist_for_each_entry(common, &hash->table[bucket], hash_entry) {
1229 		if (idx++ < *idx_s)
1230 			continue;
1231 
1232 		if (batadv_tt_local_dump_entry(msg, portid, cb, bat_priv,
1233 					       common)) {
1234 			spin_unlock_bh(&hash->list_locks[bucket]);
1235 			*idx_s = idx - 1;
1236 			return -EMSGSIZE;
1237 		}
1238 	}
1239 	spin_unlock_bh(&hash->list_locks[bucket]);
1240 
1241 	*idx_s = 0;
1242 	return 0;
1243 }
1244 
1245 /**
1246  * batadv_tt_local_dump() - Dump TT local entries into a message
1247  * @msg: Netlink message to dump into
1248  * @cb: Parameters from query
1249  *
1250  * Return: Error code, or 0 on success
1251  */
1252 int batadv_tt_local_dump(struct sk_buff *msg, struct netlink_callback *cb)
1253 {
1254 	struct net *net = sock_net(cb->skb->sk);
1255 	struct net_device *soft_iface;
1256 	struct batadv_priv *bat_priv;
1257 	struct batadv_hard_iface *primary_if = NULL;
1258 	struct batadv_hashtable *hash;
1259 	int ret;
1260 	int ifindex;
1261 	int bucket = cb->args[0];
1262 	int idx = cb->args[1];
1263 	int portid = NETLINK_CB(cb->skb).portid;
1264 
1265 	ifindex = batadv_netlink_get_ifindex(cb->nlh, BATADV_ATTR_MESH_IFINDEX);
1266 	if (!ifindex)
1267 		return -EINVAL;
1268 
1269 	soft_iface = dev_get_by_index(net, ifindex);
1270 	if (!soft_iface || !batadv_softif_is_valid(soft_iface)) {
1271 		ret = -ENODEV;
1272 		goto out;
1273 	}
1274 
1275 	bat_priv = netdev_priv(soft_iface);
1276 
1277 	primary_if = batadv_primary_if_get_selected(bat_priv);
1278 	if (!primary_if || primary_if->if_status != BATADV_IF_ACTIVE) {
1279 		ret = -ENOENT;
1280 		goto out;
1281 	}
1282 
1283 	hash = bat_priv->tt.local_hash;
1284 
1285 	while (bucket < hash->size) {
1286 		if (batadv_tt_local_dump_bucket(msg, portid, cb, bat_priv,
1287 						hash, bucket, &idx))
1288 			break;
1289 
1290 		bucket++;
1291 	}
1292 
1293 	ret = msg->len;
1294 
1295  out:
1296 	if (primary_if)
1297 		batadv_hardif_put(primary_if);
1298 	if (soft_iface)
1299 		dev_put(soft_iface);
1300 
1301 	cb->args[0] = bucket;
1302 	cb->args[1] = idx;
1303 
1304 	return ret;
1305 }
1306 
1307 static void
1308 batadv_tt_local_set_pending(struct batadv_priv *bat_priv,
1309 			    struct batadv_tt_local_entry *tt_local_entry,
1310 			    u16 flags, const char *message)
1311 {
1312 	batadv_tt_local_event(bat_priv, tt_local_entry, flags);
1313 
1314 	/* The local client has to be marked as "pending to be removed" but has
1315 	 * to be kept in the table in order to send it in a full table
1316 	 * response issued before the net ttvn increment (consistency check)
1317 	 */
1318 	tt_local_entry->common.flags |= BATADV_TT_CLIENT_PENDING;
1319 
1320 	batadv_dbg(BATADV_DBG_TT, bat_priv,
1321 		   "Local tt entry (%pM, vid: %d) pending to be removed: %s\n",
1322 		   tt_local_entry->common.addr,
1323 		   batadv_print_vid(tt_local_entry->common.vid), message);
1324 }
1325 
1326 /**
1327  * batadv_tt_local_remove() - logically remove an entry from the local table
1328  * @bat_priv: the bat priv with all the soft interface information
1329  * @addr: the MAC address of the client to remove
1330  * @vid: VLAN identifier
1331  * @message: message to append to the log on deletion
1332  * @roaming: true if the deletion is due to a roaming event
1333  *
1334  * Return: the flags assigned to the local entry before being deleted
1335  */
1336 u16 batadv_tt_local_remove(struct batadv_priv *bat_priv, const u8 *addr,
1337 			   unsigned short vid, const char *message,
1338 			   bool roaming)
1339 {
1340 	struct batadv_tt_local_entry *tt_local_entry;
1341 	u16 flags, curr_flags = BATADV_NO_FLAGS;
1342 	void *tt_entry_exists;
1343 
1344 	tt_local_entry = batadv_tt_local_hash_find(bat_priv, addr, vid);
1345 	if (!tt_local_entry)
1346 		goto out;
1347 
1348 	curr_flags = tt_local_entry->common.flags;
1349 
1350 	flags = BATADV_TT_CLIENT_DEL;
1351 	/* if this global entry addition is due to a roaming, the node has to
1352 	 * mark the local entry as "roamed" in order to correctly reroute
1353 	 * packets later
1354 	 */
1355 	if (roaming) {
1356 		flags |= BATADV_TT_CLIENT_ROAM;
1357 		/* mark the local client as ROAMed */
1358 		tt_local_entry->common.flags |= BATADV_TT_CLIENT_ROAM;
1359 	}
1360 
1361 	if (!(tt_local_entry->common.flags & BATADV_TT_CLIENT_NEW)) {
1362 		batadv_tt_local_set_pending(bat_priv, tt_local_entry, flags,
1363 					    message);
1364 		goto out;
1365 	}
1366 	/* if this client has been added right now, it is possible to
1367 	 * immediately purge it
1368 	 */
1369 	batadv_tt_local_event(bat_priv, tt_local_entry, BATADV_TT_CLIENT_DEL);
1370 
1371 	tt_entry_exists = batadv_hash_remove(bat_priv->tt.local_hash,
1372 					     batadv_compare_tt,
1373 					     batadv_choose_tt,
1374 					     &tt_local_entry->common);
1375 	if (!tt_entry_exists)
1376 		goto out;
1377 
1378 	/* extra call to free the local tt entry */
1379 	batadv_tt_local_entry_put(tt_local_entry);
1380 
1381 out:
1382 	if (tt_local_entry)
1383 		batadv_tt_local_entry_put(tt_local_entry);
1384 
1385 	return curr_flags;
1386 }
1387 
1388 /**
1389  * batadv_tt_local_purge_list() - purge inactive tt local entries
1390  * @bat_priv: the bat priv with all the soft interface information
1391  * @head: pointer to the list containing the local tt entries
1392  * @timeout: parameter deciding whether a given tt local entry is considered
1393  *  inactive or not
1394  */
1395 static void batadv_tt_local_purge_list(struct batadv_priv *bat_priv,
1396 				       struct hlist_head *head,
1397 				       int timeout)
1398 {
1399 	struct batadv_tt_local_entry *tt_local_entry;
1400 	struct batadv_tt_common_entry *tt_common_entry;
1401 	struct hlist_node *node_tmp;
1402 
1403 	hlist_for_each_entry_safe(tt_common_entry, node_tmp, head,
1404 				  hash_entry) {
1405 		tt_local_entry = container_of(tt_common_entry,
1406 					      struct batadv_tt_local_entry,
1407 					      common);
1408 		if (tt_local_entry->common.flags & BATADV_TT_CLIENT_NOPURGE)
1409 			continue;
1410 
1411 		/* entry already marked for deletion */
1412 		if (tt_local_entry->common.flags & BATADV_TT_CLIENT_PENDING)
1413 			continue;
1414 
1415 		if (!batadv_has_timed_out(tt_local_entry->last_seen, timeout))
1416 			continue;
1417 
1418 		batadv_tt_local_set_pending(bat_priv, tt_local_entry,
1419 					    BATADV_TT_CLIENT_DEL, "timed out");
1420 	}
1421 }
1422 
1423 /**
1424  * batadv_tt_local_purge() - purge inactive tt local entries
1425  * @bat_priv: the bat priv with all the soft interface information
1426  * @timeout: parameter deciding whether a given tt local entry is considered
1427  *  inactive or not
1428  */
1429 static void batadv_tt_local_purge(struct batadv_priv *bat_priv,
1430 				  int timeout)
1431 {
1432 	struct batadv_hashtable *hash = bat_priv->tt.local_hash;
1433 	struct hlist_head *head;
1434 	spinlock_t *list_lock; /* protects write access to the hash lists */
1435 	u32 i;
1436 
1437 	for (i = 0; i < hash->size; i++) {
1438 		head = &hash->table[i];
1439 		list_lock = &hash->list_locks[i];
1440 
1441 		spin_lock_bh(list_lock);
1442 		batadv_tt_local_purge_list(bat_priv, head, timeout);
1443 		spin_unlock_bh(list_lock);
1444 	}
1445 }
1446 
1447 static void batadv_tt_local_table_free(struct batadv_priv *bat_priv)
1448 {
1449 	struct batadv_hashtable *hash;
1450 	spinlock_t *list_lock; /* protects write access to the hash lists */
1451 	struct batadv_tt_common_entry *tt_common_entry;
1452 	struct batadv_tt_local_entry *tt_local;
1453 	struct hlist_node *node_tmp;
1454 	struct hlist_head *head;
1455 	u32 i;
1456 
1457 	if (!bat_priv->tt.local_hash)
1458 		return;
1459 
1460 	hash = bat_priv->tt.local_hash;
1461 
1462 	for (i = 0; i < hash->size; i++) {
1463 		head = &hash->table[i];
1464 		list_lock = &hash->list_locks[i];
1465 
1466 		spin_lock_bh(list_lock);
1467 		hlist_for_each_entry_safe(tt_common_entry, node_tmp,
1468 					  head, hash_entry) {
1469 			hlist_del_rcu(&tt_common_entry->hash_entry);
1470 			tt_local = container_of(tt_common_entry,
1471 						struct batadv_tt_local_entry,
1472 						common);
1473 
1474 			batadv_tt_local_entry_put(tt_local);
1475 		}
1476 		spin_unlock_bh(list_lock);
1477 	}
1478 
1479 	batadv_hash_destroy(hash);
1480 
1481 	bat_priv->tt.local_hash = NULL;
1482 }
1483 
1484 static int batadv_tt_global_init(struct batadv_priv *bat_priv)
1485 {
1486 	if (bat_priv->tt.global_hash)
1487 		return 0;
1488 
1489 	bat_priv->tt.global_hash = batadv_hash_new(1024);
1490 
1491 	if (!bat_priv->tt.global_hash)
1492 		return -ENOMEM;
1493 
1494 	batadv_hash_set_lock_class(bat_priv->tt.global_hash,
1495 				   &batadv_tt_global_hash_lock_class_key);
1496 
1497 	return 0;
1498 }
1499 
1500 static void batadv_tt_changes_list_free(struct batadv_priv *bat_priv)
1501 {
1502 	struct batadv_tt_change_node *entry, *safe;
1503 
1504 	spin_lock_bh(&bat_priv->tt.changes_list_lock);
1505 
1506 	list_for_each_entry_safe(entry, safe, &bat_priv->tt.changes_list,
1507 				 list) {
1508 		list_del(&entry->list);
1509 		kmem_cache_free(batadv_tt_change_cache, entry);
1510 	}
1511 
1512 	atomic_set(&bat_priv->tt.local_changes, 0);
1513 	spin_unlock_bh(&bat_priv->tt.changes_list_lock);
1514 }
1515 
1516 /**
1517  * batadv_tt_global_orig_entry_find() - find a TT orig_list_entry
1518  * @entry: the TT global entry where the orig_list_entry has to be
1519  *  extracted from
1520  * @orig_node: the originator for which the orig_list_entry has to be found
1521  *
1522  * retrieve the orig_tt_list_entry belonging to orig_node from the
1523  * batadv_tt_global_entry list
1524  *
1525  * Return: it with an increased refcounter, NULL if not found
1526  */
1527 static struct batadv_tt_orig_list_entry *
1528 batadv_tt_global_orig_entry_find(const struct batadv_tt_global_entry *entry,
1529 				 const struct batadv_orig_node *orig_node)
1530 {
1531 	struct batadv_tt_orig_list_entry *tmp_orig_entry, *orig_entry = NULL;
1532 	const struct hlist_head *head;
1533 
1534 	rcu_read_lock();
1535 	head = &entry->orig_list;
1536 	hlist_for_each_entry_rcu(tmp_orig_entry, head, list) {
1537 		if (tmp_orig_entry->orig_node != orig_node)
1538 			continue;
1539 		if (!kref_get_unless_zero(&tmp_orig_entry->refcount))
1540 			continue;
1541 
1542 		orig_entry = tmp_orig_entry;
1543 		break;
1544 	}
1545 	rcu_read_unlock();
1546 
1547 	return orig_entry;
1548 }
1549 
1550 /**
1551  * batadv_tt_global_entry_has_orig() - check if a TT global entry is also
1552  *  handled by a given originator
1553  * @entry: the TT global entry to check
1554  * @orig_node: the originator to search in the list
1555  * @flags: a pointer to store TT flags for the given @entry received
1556  *  from @orig_node
1557  *
1558  * find out if an orig_node is already in the list of a tt_global_entry.
1559  *
1560  * Return: true if found, false otherwise
1561  */
1562 static bool
1563 batadv_tt_global_entry_has_orig(const struct batadv_tt_global_entry *entry,
1564 				const struct batadv_orig_node *orig_node,
1565 				u8 *flags)
1566 {
1567 	struct batadv_tt_orig_list_entry *orig_entry;
1568 	bool found = false;
1569 
1570 	orig_entry = batadv_tt_global_orig_entry_find(entry, orig_node);
1571 	if (orig_entry) {
1572 		found = true;
1573 
1574 		if (flags)
1575 			*flags = orig_entry->flags;
1576 
1577 		batadv_tt_orig_list_entry_put(orig_entry);
1578 	}
1579 
1580 	return found;
1581 }
1582 
1583 /**
1584  * batadv_tt_global_sync_flags() - update TT sync flags
1585  * @tt_global: the TT global entry to update sync flags in
1586  *
1587  * Updates the sync flag bits in the tt_global flag attribute with a logical
1588  * OR of all sync flags from any of its TT orig entries.
1589  */
1590 static void
1591 batadv_tt_global_sync_flags(struct batadv_tt_global_entry *tt_global)
1592 {
1593 	struct batadv_tt_orig_list_entry *orig_entry;
1594 	const struct hlist_head *head;
1595 	u16 flags = BATADV_NO_FLAGS;
1596 
1597 	rcu_read_lock();
1598 	head = &tt_global->orig_list;
1599 	hlist_for_each_entry_rcu(orig_entry, head, list)
1600 		flags |= orig_entry->flags;
1601 	rcu_read_unlock();
1602 
1603 	flags |= tt_global->common.flags & (~BATADV_TT_SYNC_MASK);
1604 	tt_global->common.flags = flags;
1605 }
1606 
1607 /**
1608  * batadv_tt_global_orig_entry_add() - add or update a TT orig entry
1609  * @tt_global: the TT global entry to add an orig entry in
1610  * @orig_node: the originator to add an orig entry for
1611  * @ttvn: translation table version number of this changeset
1612  * @flags: TT sync flags
1613  */
1614 static void
1615 batadv_tt_global_orig_entry_add(struct batadv_tt_global_entry *tt_global,
1616 				struct batadv_orig_node *orig_node, int ttvn,
1617 				u8 flags)
1618 {
1619 	struct batadv_tt_orig_list_entry *orig_entry;
1620 
1621 	spin_lock_bh(&tt_global->list_lock);
1622 
1623 	orig_entry = batadv_tt_global_orig_entry_find(tt_global, orig_node);
1624 	if (orig_entry) {
1625 		/* refresh the ttvn: the current value could be a bogus one that
1626 		 * was added during a "temporary client detection"
1627 		 */
1628 		orig_entry->ttvn = ttvn;
1629 		orig_entry->flags = flags;
1630 		goto sync_flags;
1631 	}
1632 
1633 	orig_entry = kmem_cache_zalloc(batadv_tt_orig_cache, GFP_ATOMIC);
1634 	if (!orig_entry)
1635 		goto out;
1636 
1637 	INIT_HLIST_NODE(&orig_entry->list);
1638 	kref_get(&orig_node->refcount);
1639 	batadv_tt_global_size_inc(orig_node, tt_global->common.vid);
1640 	orig_entry->orig_node = orig_node;
1641 	orig_entry->ttvn = ttvn;
1642 	orig_entry->flags = flags;
1643 	kref_init(&orig_entry->refcount);
1644 
1645 	kref_get(&orig_entry->refcount);
1646 	hlist_add_head_rcu(&orig_entry->list,
1647 			   &tt_global->orig_list);
1648 	atomic_inc(&tt_global->orig_list_count);
1649 
1650 sync_flags:
1651 	batadv_tt_global_sync_flags(tt_global);
1652 out:
1653 	if (orig_entry)
1654 		batadv_tt_orig_list_entry_put(orig_entry);
1655 
1656 	spin_unlock_bh(&tt_global->list_lock);
1657 }
1658 
1659 /**
1660  * batadv_tt_global_add() - add a new TT global entry or update an existing one
1661  * @bat_priv: the bat priv with all the soft interface information
1662  * @orig_node: the originator announcing the client
1663  * @tt_addr: the mac address of the non-mesh client
1664  * @vid: VLAN identifier
1665  * @flags: TT flags that have to be set for this non-mesh client
1666  * @ttvn: the tt version number ever announcing this non-mesh client
1667  *
1668  * Add a new TT global entry for the given originator. If the entry already
1669  * exists add a new reference to the given originator (a global entry can have
1670  * references to multiple originators) and adjust the flags attribute to reflect
1671  * the function argument.
1672  * If a TT local entry exists for this non-mesh client remove it.
1673  *
1674  * The caller must hold orig_node refcount.
1675  *
1676  * Return: true if the new entry has been added, false otherwise
1677  */
1678 static bool batadv_tt_global_add(struct batadv_priv *bat_priv,
1679 				 struct batadv_orig_node *orig_node,
1680 				 const unsigned char *tt_addr,
1681 				 unsigned short vid, u16 flags, u8 ttvn)
1682 {
1683 	struct batadv_tt_global_entry *tt_global_entry;
1684 	struct batadv_tt_local_entry *tt_local_entry;
1685 	bool ret = false;
1686 	int hash_added;
1687 	struct batadv_tt_common_entry *common;
1688 	u16 local_flags;
1689 
1690 	/* ignore global entries from backbone nodes */
1691 	if (batadv_bla_is_backbone_gw_orig(bat_priv, orig_node->orig, vid))
1692 		return true;
1693 
1694 	tt_global_entry = batadv_tt_global_hash_find(bat_priv, tt_addr, vid);
1695 	tt_local_entry = batadv_tt_local_hash_find(bat_priv, tt_addr, vid);
1696 
1697 	/* if the node already has a local client for this entry, it has to wait
1698 	 * for a roaming advertisement instead of manually messing up the global
1699 	 * table
1700 	 */
1701 	if ((flags & BATADV_TT_CLIENT_TEMP) && tt_local_entry &&
1702 	    !(tt_local_entry->common.flags & BATADV_TT_CLIENT_NEW))
1703 		goto out;
1704 
1705 	if (!tt_global_entry) {
1706 		tt_global_entry = kmem_cache_zalloc(batadv_tg_cache,
1707 						    GFP_ATOMIC);
1708 		if (!tt_global_entry)
1709 			goto out;
1710 
1711 		common = &tt_global_entry->common;
1712 		ether_addr_copy(common->addr, tt_addr);
1713 		common->vid = vid;
1714 
1715 		if (!is_multicast_ether_addr(common->addr))
1716 			common->flags = flags & (~BATADV_TT_SYNC_MASK);
1717 
1718 		tt_global_entry->roam_at = 0;
1719 		/* node must store current time in case of roaming. This is
1720 		 * needed to purge this entry out on timeout (if nobody claims
1721 		 * it)
1722 		 */
1723 		if (flags & BATADV_TT_CLIENT_ROAM)
1724 			tt_global_entry->roam_at = jiffies;
1725 		kref_init(&common->refcount);
1726 		common->added_at = jiffies;
1727 
1728 		INIT_HLIST_HEAD(&tt_global_entry->orig_list);
1729 		atomic_set(&tt_global_entry->orig_list_count, 0);
1730 		spin_lock_init(&tt_global_entry->list_lock);
1731 
1732 		kref_get(&common->refcount);
1733 		hash_added = batadv_hash_add(bat_priv->tt.global_hash,
1734 					     batadv_compare_tt,
1735 					     batadv_choose_tt, common,
1736 					     &common->hash_entry);
1737 
1738 		if (unlikely(hash_added != 0)) {
1739 			/* remove the reference for the hash */
1740 			batadv_tt_global_entry_put(tt_global_entry);
1741 			goto out_remove;
1742 		}
1743 	} else {
1744 		common = &tt_global_entry->common;
1745 		/* If there is already a global entry, we can use this one for
1746 		 * our processing.
1747 		 * But if we are trying to add a temporary client then here are
1748 		 * two options at this point:
1749 		 * 1) the global client is not a temporary client: the global
1750 		 *    client has to be left as it is, temporary information
1751 		 *    should never override any already known client state
1752 		 * 2) the global client is a temporary client: purge the
1753 		 *    originator list and add the new one orig_entry
1754 		 */
1755 		if (flags & BATADV_TT_CLIENT_TEMP) {
1756 			if (!(common->flags & BATADV_TT_CLIENT_TEMP))
1757 				goto out;
1758 			if (batadv_tt_global_entry_has_orig(tt_global_entry,
1759 							    orig_node, NULL))
1760 				goto out_remove;
1761 			batadv_tt_global_del_orig_list(tt_global_entry);
1762 			goto add_orig_entry;
1763 		}
1764 
1765 		/* if the client was temporary added before receiving the first
1766 		 * OGM announcing it, we have to clear the TEMP flag. Also,
1767 		 * remove the previous temporary orig node and re-add it
1768 		 * if required. If the orig entry changed, the new one which
1769 		 * is a non-temporary entry is preferred.
1770 		 */
1771 		if (common->flags & BATADV_TT_CLIENT_TEMP) {
1772 			batadv_tt_global_del_orig_list(tt_global_entry);
1773 			common->flags &= ~BATADV_TT_CLIENT_TEMP;
1774 		}
1775 
1776 		/* the change can carry possible "attribute" flags like the
1777 		 * TT_CLIENT_TEMP, therefore they have to be copied in the
1778 		 * client entry
1779 		 */
1780 		if (!is_multicast_ether_addr(common->addr))
1781 			common->flags |= flags & (~BATADV_TT_SYNC_MASK);
1782 
1783 		/* If there is the BATADV_TT_CLIENT_ROAM flag set, there is only
1784 		 * one originator left in the list and we previously received a
1785 		 * delete + roaming change for this originator.
1786 		 *
1787 		 * We should first delete the old originator before adding the
1788 		 * new one.
1789 		 */
1790 		if (common->flags & BATADV_TT_CLIENT_ROAM) {
1791 			batadv_tt_global_del_orig_list(tt_global_entry);
1792 			common->flags &= ~BATADV_TT_CLIENT_ROAM;
1793 			tt_global_entry->roam_at = 0;
1794 		}
1795 	}
1796 add_orig_entry:
1797 	/* add the new orig_entry (if needed) or update it */
1798 	batadv_tt_global_orig_entry_add(tt_global_entry, orig_node, ttvn,
1799 					flags & BATADV_TT_SYNC_MASK);
1800 
1801 	batadv_dbg(BATADV_DBG_TT, bat_priv,
1802 		   "Creating new global tt entry: %pM (vid: %d, via %pM)\n",
1803 		   common->addr, batadv_print_vid(common->vid),
1804 		   orig_node->orig);
1805 	ret = true;
1806 
1807 out_remove:
1808 	/* Do not remove multicast addresses from the local hash on
1809 	 * global additions
1810 	 */
1811 	if (is_multicast_ether_addr(tt_addr))
1812 		goto out;
1813 
1814 	/* remove address from local hash if present */
1815 	local_flags = batadv_tt_local_remove(bat_priv, tt_addr, vid,
1816 					     "global tt received",
1817 					     flags & BATADV_TT_CLIENT_ROAM);
1818 	tt_global_entry->common.flags |= local_flags & BATADV_TT_CLIENT_WIFI;
1819 
1820 	if (!(flags & BATADV_TT_CLIENT_ROAM))
1821 		/* this is a normal global add. Therefore the client is not in a
1822 		 * roaming state anymore.
1823 		 */
1824 		tt_global_entry->common.flags &= ~BATADV_TT_CLIENT_ROAM;
1825 
1826 out:
1827 	if (tt_global_entry)
1828 		batadv_tt_global_entry_put(tt_global_entry);
1829 	if (tt_local_entry)
1830 		batadv_tt_local_entry_put(tt_local_entry);
1831 	return ret;
1832 }
1833 
1834 /**
1835  * batadv_transtable_best_orig() - Get best originator list entry from tt entry
1836  * @bat_priv: the bat priv with all the soft interface information
1837  * @tt_global_entry: global translation table entry to be analyzed
1838  *
1839  * This functon assumes the caller holds rcu_read_lock().
1840  * Return: best originator list entry or NULL on errors.
1841  */
1842 static struct batadv_tt_orig_list_entry *
1843 batadv_transtable_best_orig(struct batadv_priv *bat_priv,
1844 			    struct batadv_tt_global_entry *tt_global_entry)
1845 {
1846 	struct batadv_neigh_node *router, *best_router = NULL;
1847 	struct batadv_algo_ops *bao = bat_priv->algo_ops;
1848 	struct hlist_head *head;
1849 	struct batadv_tt_orig_list_entry *orig_entry, *best_entry = NULL;
1850 
1851 	head = &tt_global_entry->orig_list;
1852 	hlist_for_each_entry_rcu(orig_entry, head, list) {
1853 		router = batadv_orig_router_get(orig_entry->orig_node,
1854 						BATADV_IF_DEFAULT);
1855 		if (!router)
1856 			continue;
1857 
1858 		if (best_router &&
1859 		    bao->neigh.cmp(router, BATADV_IF_DEFAULT, best_router,
1860 				   BATADV_IF_DEFAULT) <= 0) {
1861 			batadv_neigh_node_put(router);
1862 			continue;
1863 		}
1864 
1865 		/* release the refcount for the "old" best */
1866 		if (best_router)
1867 			batadv_neigh_node_put(best_router);
1868 
1869 		best_entry = orig_entry;
1870 		best_router = router;
1871 	}
1872 
1873 	if (best_router)
1874 		batadv_neigh_node_put(best_router);
1875 
1876 	return best_entry;
1877 }
1878 
1879 #ifdef CONFIG_BATMAN_ADV_DEBUGFS
1880 /**
1881  * batadv_tt_global_print_entry() - print all orig nodes who announce the
1882  *  address for this global entry
1883  * @bat_priv: the bat priv with all the soft interface information
1884  * @tt_global_entry: global translation table entry to be printed
1885  * @seq: debugfs table seq_file struct
1886  *
1887  * This functon assumes the caller holds rcu_read_lock().
1888  */
1889 static void
1890 batadv_tt_global_print_entry(struct batadv_priv *bat_priv,
1891 			     struct batadv_tt_global_entry *tt_global_entry,
1892 			     struct seq_file *seq)
1893 {
1894 	struct batadv_tt_orig_list_entry *orig_entry, *best_entry;
1895 	struct batadv_tt_common_entry *tt_common_entry;
1896 	struct batadv_orig_node_vlan *vlan;
1897 	struct hlist_head *head;
1898 	u8 last_ttvn;
1899 	u16 flags;
1900 
1901 	tt_common_entry = &tt_global_entry->common;
1902 	flags = tt_common_entry->flags;
1903 
1904 	best_entry = batadv_transtable_best_orig(bat_priv, tt_global_entry);
1905 	if (best_entry) {
1906 		vlan = batadv_orig_node_vlan_get(best_entry->orig_node,
1907 						 tt_common_entry->vid);
1908 		if (!vlan) {
1909 			seq_printf(seq,
1910 				   " * Cannot retrieve VLAN %d for originator %pM\n",
1911 				   batadv_print_vid(tt_common_entry->vid),
1912 				   best_entry->orig_node->orig);
1913 			goto print_list;
1914 		}
1915 
1916 		last_ttvn = atomic_read(&best_entry->orig_node->last_ttvn);
1917 		seq_printf(seq,
1918 			   " %c %pM %4i   (%3u) via %pM     (%3u)   (%#.8x) [%c%c%c%c]\n",
1919 			   '*', tt_global_entry->common.addr,
1920 			   batadv_print_vid(tt_global_entry->common.vid),
1921 			   best_entry->ttvn, best_entry->orig_node->orig,
1922 			   last_ttvn, vlan->tt.crc,
1923 			   ((flags & BATADV_TT_CLIENT_ROAM) ? 'R' : '.'),
1924 			   ((flags & BATADV_TT_CLIENT_WIFI) ? 'W' : '.'),
1925 			   ((flags & BATADV_TT_CLIENT_ISOLA) ? 'I' : '.'),
1926 			   ((flags & BATADV_TT_CLIENT_TEMP) ? 'T' : '.'));
1927 
1928 		batadv_orig_node_vlan_put(vlan);
1929 	}
1930 
1931 print_list:
1932 	head = &tt_global_entry->orig_list;
1933 
1934 	hlist_for_each_entry_rcu(orig_entry, head, list) {
1935 		if (best_entry == orig_entry)
1936 			continue;
1937 
1938 		vlan = batadv_orig_node_vlan_get(orig_entry->orig_node,
1939 						 tt_common_entry->vid);
1940 		if (!vlan) {
1941 			seq_printf(seq,
1942 				   " + Cannot retrieve VLAN %d for originator %pM\n",
1943 				   batadv_print_vid(tt_common_entry->vid),
1944 				   orig_entry->orig_node->orig);
1945 			continue;
1946 		}
1947 
1948 		last_ttvn = atomic_read(&orig_entry->orig_node->last_ttvn);
1949 		seq_printf(seq,
1950 			   " %c %pM %4d   (%3u) via %pM     (%3u)   (%#.8x) [%c%c%c%c]\n",
1951 			   '+', tt_global_entry->common.addr,
1952 			   batadv_print_vid(tt_global_entry->common.vid),
1953 			   orig_entry->ttvn, orig_entry->orig_node->orig,
1954 			   last_ttvn, vlan->tt.crc,
1955 			   ((flags & BATADV_TT_CLIENT_ROAM) ? 'R' : '.'),
1956 			   ((flags & BATADV_TT_CLIENT_WIFI) ? 'W' : '.'),
1957 			   ((flags & BATADV_TT_CLIENT_ISOLA) ? 'I' : '.'),
1958 			   ((flags & BATADV_TT_CLIENT_TEMP) ? 'T' : '.'));
1959 
1960 		batadv_orig_node_vlan_put(vlan);
1961 	}
1962 }
1963 
1964 /**
1965  * batadv_tt_global_seq_print_text() - Print the global tt table in a seq file
1966  * @seq: seq file to print on
1967  * @offset: not used
1968  *
1969  * Return: always 0
1970  */
1971 int batadv_tt_global_seq_print_text(struct seq_file *seq, void *offset)
1972 {
1973 	struct net_device *net_dev = (struct net_device *)seq->private;
1974 	struct batadv_priv *bat_priv = netdev_priv(net_dev);
1975 	struct batadv_hashtable *hash = bat_priv->tt.global_hash;
1976 	struct batadv_tt_common_entry *tt_common_entry;
1977 	struct batadv_tt_global_entry *tt_global;
1978 	struct batadv_hard_iface *primary_if;
1979 	struct hlist_head *head;
1980 	u32 i;
1981 
1982 	primary_if = batadv_seq_print_text_primary_if_get(seq);
1983 	if (!primary_if)
1984 		goto out;
1985 
1986 	seq_printf(seq,
1987 		   "Globally announced TT entries received via the mesh %s\n",
1988 		   net_dev->name);
1989 	seq_puts(seq,
1990 		 "       Client         VID  (TTVN)       Originator      (Curr TTVN) (CRC       ) Flags\n");
1991 
1992 	for (i = 0; i < hash->size; i++) {
1993 		head = &hash->table[i];
1994 
1995 		rcu_read_lock();
1996 		hlist_for_each_entry_rcu(tt_common_entry,
1997 					 head, hash_entry) {
1998 			tt_global = container_of(tt_common_entry,
1999 						 struct batadv_tt_global_entry,
2000 						 common);
2001 			batadv_tt_global_print_entry(bat_priv, tt_global, seq);
2002 		}
2003 		rcu_read_unlock();
2004 	}
2005 out:
2006 	if (primary_if)
2007 		batadv_hardif_put(primary_if);
2008 	return 0;
2009 }
2010 #endif
2011 
2012 /**
2013  * batadv_tt_global_dump_subentry() - Dump all TT local entries into a message
2014  * @msg: Netlink message to dump into
2015  * @portid: Port making netlink request
2016  * @seq: Sequence number of netlink message
2017  * @common: tt local & tt global common data
2018  * @orig: Originator node announcing a non-mesh client
2019  * @best: Is the best originator for the TT entry
2020  *
2021  * Return: Error code, or 0 on success
2022  */
2023 static int
2024 batadv_tt_global_dump_subentry(struct sk_buff *msg, u32 portid, u32 seq,
2025 			       struct batadv_tt_common_entry *common,
2026 			       struct batadv_tt_orig_list_entry *orig,
2027 			       bool best)
2028 {
2029 	u16 flags = (common->flags & (~BATADV_TT_SYNC_MASK)) | orig->flags;
2030 	void *hdr;
2031 	struct batadv_orig_node_vlan *vlan;
2032 	u8 last_ttvn;
2033 	u32 crc;
2034 
2035 	vlan = batadv_orig_node_vlan_get(orig->orig_node,
2036 					 common->vid);
2037 	if (!vlan)
2038 		return 0;
2039 
2040 	crc = vlan->tt.crc;
2041 
2042 	batadv_orig_node_vlan_put(vlan);
2043 
2044 	hdr = genlmsg_put(msg, portid, seq, &batadv_netlink_family,
2045 			  NLM_F_MULTI,
2046 			  BATADV_CMD_GET_TRANSTABLE_GLOBAL);
2047 	if (!hdr)
2048 		return -ENOBUFS;
2049 
2050 	last_ttvn = atomic_read(&orig->orig_node->last_ttvn);
2051 
2052 	if (nla_put(msg, BATADV_ATTR_TT_ADDRESS, ETH_ALEN, common->addr) ||
2053 	    nla_put(msg, BATADV_ATTR_ORIG_ADDRESS, ETH_ALEN,
2054 		    orig->orig_node->orig) ||
2055 	    nla_put_u8(msg, BATADV_ATTR_TT_TTVN, orig->ttvn) ||
2056 	    nla_put_u8(msg, BATADV_ATTR_TT_LAST_TTVN, last_ttvn) ||
2057 	    nla_put_u32(msg, BATADV_ATTR_TT_CRC32, crc) ||
2058 	    nla_put_u16(msg, BATADV_ATTR_TT_VID, common->vid) ||
2059 	    nla_put_u32(msg, BATADV_ATTR_TT_FLAGS, flags))
2060 		goto nla_put_failure;
2061 
2062 	if (best && nla_put_flag(msg, BATADV_ATTR_FLAG_BEST))
2063 		goto nla_put_failure;
2064 
2065 	genlmsg_end(msg, hdr);
2066 	return 0;
2067 
2068  nla_put_failure:
2069 	genlmsg_cancel(msg, hdr);
2070 	return -EMSGSIZE;
2071 }
2072 
2073 /**
2074  * batadv_tt_global_dump_entry() - Dump one TT global entry into a message
2075  * @msg: Netlink message to dump into
2076  * @portid: Port making netlink request
2077  * @seq: Sequence number of netlink message
2078  * @bat_priv: The bat priv with all the soft interface information
2079  * @common: tt local & tt global common data
2080  * @sub_s: Number of entries to skip
2081  *
2082  * This function assumes the caller holds rcu_read_lock().
2083  *
2084  * Return: Error code, or 0 on success
2085  */
2086 static int
2087 batadv_tt_global_dump_entry(struct sk_buff *msg, u32 portid, u32 seq,
2088 			    struct batadv_priv *bat_priv,
2089 			    struct batadv_tt_common_entry *common, int *sub_s)
2090 {
2091 	struct batadv_tt_orig_list_entry *orig_entry, *best_entry;
2092 	struct batadv_tt_global_entry *global;
2093 	struct hlist_head *head;
2094 	int sub = 0;
2095 	bool best;
2096 
2097 	global = container_of(common, struct batadv_tt_global_entry, common);
2098 	best_entry = batadv_transtable_best_orig(bat_priv, global);
2099 	head = &global->orig_list;
2100 
2101 	hlist_for_each_entry_rcu(orig_entry, head, list) {
2102 		if (sub++ < *sub_s)
2103 			continue;
2104 
2105 		best = (orig_entry == best_entry);
2106 
2107 		if (batadv_tt_global_dump_subentry(msg, portid, seq, common,
2108 						   orig_entry, best)) {
2109 			*sub_s = sub - 1;
2110 			return -EMSGSIZE;
2111 		}
2112 	}
2113 
2114 	*sub_s = 0;
2115 	return 0;
2116 }
2117 
2118 /**
2119  * batadv_tt_global_dump_bucket() - Dump one TT local bucket into a message
2120  * @msg: Netlink message to dump into
2121  * @portid: Port making netlink request
2122  * @seq: Sequence number of netlink message
2123  * @bat_priv: The bat priv with all the soft interface information
2124  * @head: Pointer to the list containing the global tt entries
2125  * @idx_s: Number of entries to skip
2126  * @sub: Number of entries to skip
2127  *
2128  * Return: Error code, or 0 on success
2129  */
2130 static int
2131 batadv_tt_global_dump_bucket(struct sk_buff *msg, u32 portid, u32 seq,
2132 			     struct batadv_priv *bat_priv,
2133 			     struct hlist_head *head, int *idx_s, int *sub)
2134 {
2135 	struct batadv_tt_common_entry *common;
2136 	int idx = 0;
2137 
2138 	rcu_read_lock();
2139 	hlist_for_each_entry_rcu(common, head, hash_entry) {
2140 		if (idx++ < *idx_s)
2141 			continue;
2142 
2143 		if (batadv_tt_global_dump_entry(msg, portid, seq, bat_priv,
2144 						common, sub)) {
2145 			rcu_read_unlock();
2146 			*idx_s = idx - 1;
2147 			return -EMSGSIZE;
2148 		}
2149 	}
2150 	rcu_read_unlock();
2151 
2152 	*idx_s = 0;
2153 	*sub = 0;
2154 	return 0;
2155 }
2156 
2157 /**
2158  * batadv_tt_global_dump() -  Dump TT global entries into a message
2159  * @msg: Netlink message to dump into
2160  * @cb: Parameters from query
2161  *
2162  * Return: Error code, or length of message on success
2163  */
2164 int batadv_tt_global_dump(struct sk_buff *msg, struct netlink_callback *cb)
2165 {
2166 	struct net *net = sock_net(cb->skb->sk);
2167 	struct net_device *soft_iface;
2168 	struct batadv_priv *bat_priv;
2169 	struct batadv_hard_iface *primary_if = NULL;
2170 	struct batadv_hashtable *hash;
2171 	struct hlist_head *head;
2172 	int ret;
2173 	int ifindex;
2174 	int bucket = cb->args[0];
2175 	int idx = cb->args[1];
2176 	int sub = cb->args[2];
2177 	int portid = NETLINK_CB(cb->skb).portid;
2178 
2179 	ifindex = batadv_netlink_get_ifindex(cb->nlh, BATADV_ATTR_MESH_IFINDEX);
2180 	if (!ifindex)
2181 		return -EINVAL;
2182 
2183 	soft_iface = dev_get_by_index(net, ifindex);
2184 	if (!soft_iface || !batadv_softif_is_valid(soft_iface)) {
2185 		ret = -ENODEV;
2186 		goto out;
2187 	}
2188 
2189 	bat_priv = netdev_priv(soft_iface);
2190 
2191 	primary_if = batadv_primary_if_get_selected(bat_priv);
2192 	if (!primary_if || primary_if->if_status != BATADV_IF_ACTIVE) {
2193 		ret = -ENOENT;
2194 		goto out;
2195 	}
2196 
2197 	hash = bat_priv->tt.global_hash;
2198 
2199 	while (bucket < hash->size) {
2200 		head = &hash->table[bucket];
2201 
2202 		if (batadv_tt_global_dump_bucket(msg, portid,
2203 						 cb->nlh->nlmsg_seq, bat_priv,
2204 						 head, &idx, &sub))
2205 			break;
2206 
2207 		bucket++;
2208 	}
2209 
2210 	ret = msg->len;
2211 
2212  out:
2213 	if (primary_if)
2214 		batadv_hardif_put(primary_if);
2215 	if (soft_iface)
2216 		dev_put(soft_iface);
2217 
2218 	cb->args[0] = bucket;
2219 	cb->args[1] = idx;
2220 	cb->args[2] = sub;
2221 
2222 	return ret;
2223 }
2224 
2225 /**
2226  * _batadv_tt_global_del_orig_entry() - remove and free an orig_entry
2227  * @tt_global_entry: the global entry to remove the orig_entry from
2228  * @orig_entry: the orig entry to remove and free
2229  *
2230  * Remove an orig_entry from its list in the given tt_global_entry and
2231  * free this orig_entry afterwards.
2232  *
2233  * Caller must hold tt_global_entry->list_lock and ensure orig_entry->list is
2234  * part of a list.
2235  */
2236 static void
2237 _batadv_tt_global_del_orig_entry(struct batadv_tt_global_entry *tt_global_entry,
2238 				 struct batadv_tt_orig_list_entry *orig_entry)
2239 {
2240 	lockdep_assert_held(&tt_global_entry->list_lock);
2241 
2242 	batadv_tt_global_size_dec(orig_entry->orig_node,
2243 				  tt_global_entry->common.vid);
2244 	atomic_dec(&tt_global_entry->orig_list_count);
2245 	/* requires holding tt_global_entry->list_lock and orig_entry->list
2246 	 * being part of a list
2247 	 */
2248 	hlist_del_rcu(&orig_entry->list);
2249 	batadv_tt_orig_list_entry_put(orig_entry);
2250 }
2251 
2252 /* deletes the orig list of a tt_global_entry */
2253 static void
2254 batadv_tt_global_del_orig_list(struct batadv_tt_global_entry *tt_global_entry)
2255 {
2256 	struct hlist_head *head;
2257 	struct hlist_node *safe;
2258 	struct batadv_tt_orig_list_entry *orig_entry;
2259 
2260 	spin_lock_bh(&tt_global_entry->list_lock);
2261 	head = &tt_global_entry->orig_list;
2262 	hlist_for_each_entry_safe(orig_entry, safe, head, list)
2263 		_batadv_tt_global_del_orig_entry(tt_global_entry, orig_entry);
2264 	spin_unlock_bh(&tt_global_entry->list_lock);
2265 }
2266 
2267 /**
2268  * batadv_tt_global_del_orig_node() - remove orig_node from a global tt entry
2269  * @bat_priv: the bat priv with all the soft interface information
2270  * @tt_global_entry: the global entry to remove the orig_node from
2271  * @orig_node: the originator announcing the client
2272  * @message: message to append to the log on deletion
2273  *
2274  * Remove the given orig_node and its according orig_entry from the given
2275  * global tt entry.
2276  */
2277 static void
2278 batadv_tt_global_del_orig_node(struct batadv_priv *bat_priv,
2279 			       struct batadv_tt_global_entry *tt_global_entry,
2280 			       struct batadv_orig_node *orig_node,
2281 			       const char *message)
2282 {
2283 	struct hlist_head *head;
2284 	struct hlist_node *safe;
2285 	struct batadv_tt_orig_list_entry *orig_entry;
2286 	unsigned short vid;
2287 
2288 	spin_lock_bh(&tt_global_entry->list_lock);
2289 	head = &tt_global_entry->orig_list;
2290 	hlist_for_each_entry_safe(orig_entry, safe, head, list) {
2291 		if (orig_entry->orig_node == orig_node) {
2292 			vid = tt_global_entry->common.vid;
2293 			batadv_dbg(BATADV_DBG_TT, bat_priv,
2294 				   "Deleting %pM from global tt entry %pM (vid: %d): %s\n",
2295 				   orig_node->orig,
2296 				   tt_global_entry->common.addr,
2297 				   batadv_print_vid(vid), message);
2298 			_batadv_tt_global_del_orig_entry(tt_global_entry,
2299 							 orig_entry);
2300 		}
2301 	}
2302 	spin_unlock_bh(&tt_global_entry->list_lock);
2303 }
2304 
2305 /* If the client is to be deleted, we check if it is the last origantor entry
2306  * within tt_global entry. If yes, we set the BATADV_TT_CLIENT_ROAM flag and the
2307  * timer, otherwise we simply remove the originator scheduled for deletion.
2308  */
2309 static void
2310 batadv_tt_global_del_roaming(struct batadv_priv *bat_priv,
2311 			     struct batadv_tt_global_entry *tt_global_entry,
2312 			     struct batadv_orig_node *orig_node,
2313 			     const char *message)
2314 {
2315 	bool last_entry = true;
2316 	struct hlist_head *head;
2317 	struct batadv_tt_orig_list_entry *orig_entry;
2318 
2319 	/* no local entry exists, case 1:
2320 	 * Check if this is the last one or if other entries exist.
2321 	 */
2322 
2323 	rcu_read_lock();
2324 	head = &tt_global_entry->orig_list;
2325 	hlist_for_each_entry_rcu(orig_entry, head, list) {
2326 		if (orig_entry->orig_node != orig_node) {
2327 			last_entry = false;
2328 			break;
2329 		}
2330 	}
2331 	rcu_read_unlock();
2332 
2333 	if (last_entry) {
2334 		/* its the last one, mark for roaming. */
2335 		tt_global_entry->common.flags |= BATADV_TT_CLIENT_ROAM;
2336 		tt_global_entry->roam_at = jiffies;
2337 	} else {
2338 		/* there is another entry, we can simply delete this
2339 		 * one and can still use the other one.
2340 		 */
2341 		batadv_tt_global_del_orig_node(bat_priv, tt_global_entry,
2342 					       orig_node, message);
2343 	}
2344 }
2345 
2346 /**
2347  * batadv_tt_global_del() - remove a client from the global table
2348  * @bat_priv: the bat priv with all the soft interface information
2349  * @orig_node: an originator serving this client
2350  * @addr: the mac address of the client
2351  * @vid: VLAN identifier
2352  * @message: a message explaining the reason for deleting the client to print
2353  *  for debugging purpose
2354  * @roaming: true if the deletion has been triggered by a roaming event
2355  */
2356 static void batadv_tt_global_del(struct batadv_priv *bat_priv,
2357 				 struct batadv_orig_node *orig_node,
2358 				 const unsigned char *addr, unsigned short vid,
2359 				 const char *message, bool roaming)
2360 {
2361 	struct batadv_tt_global_entry *tt_global_entry;
2362 	struct batadv_tt_local_entry *local_entry = NULL;
2363 
2364 	tt_global_entry = batadv_tt_global_hash_find(bat_priv, addr, vid);
2365 	if (!tt_global_entry)
2366 		goto out;
2367 
2368 	if (!roaming) {
2369 		batadv_tt_global_del_orig_node(bat_priv, tt_global_entry,
2370 					       orig_node, message);
2371 
2372 		if (hlist_empty(&tt_global_entry->orig_list))
2373 			batadv_tt_global_free(bat_priv, tt_global_entry,
2374 					      message);
2375 
2376 		goto out;
2377 	}
2378 
2379 	/* if we are deleting a global entry due to a roam
2380 	 * event, there are two possibilities:
2381 	 * 1) the client roamed from node A to node B => if there
2382 	 *    is only one originator left for this client, we mark
2383 	 *    it with BATADV_TT_CLIENT_ROAM, we start a timer and we
2384 	 *    wait for node B to claim it. In case of timeout
2385 	 *    the entry is purged.
2386 	 *
2387 	 *    If there are other originators left, we directly delete
2388 	 *    the originator.
2389 	 * 2) the client roamed to us => we can directly delete
2390 	 *    the global entry, since it is useless now.
2391 	 */
2392 	local_entry = batadv_tt_local_hash_find(bat_priv,
2393 						tt_global_entry->common.addr,
2394 						vid);
2395 	if (local_entry) {
2396 		/* local entry exists, case 2: client roamed to us. */
2397 		batadv_tt_global_del_orig_list(tt_global_entry);
2398 		batadv_tt_global_free(bat_priv, tt_global_entry, message);
2399 	} else {
2400 		/* no local entry exists, case 1: check for roaming */
2401 		batadv_tt_global_del_roaming(bat_priv, tt_global_entry,
2402 					     orig_node, message);
2403 	}
2404 
2405 out:
2406 	if (tt_global_entry)
2407 		batadv_tt_global_entry_put(tt_global_entry);
2408 	if (local_entry)
2409 		batadv_tt_local_entry_put(local_entry);
2410 }
2411 
2412 /**
2413  * batadv_tt_global_del_orig() - remove all the TT global entries belonging to
2414  *  the given originator matching the provided vid
2415  * @bat_priv: the bat priv with all the soft interface information
2416  * @orig_node: the originator owning the entries to remove
2417  * @match_vid: the VLAN identifier to match. If negative all the entries will be
2418  *  removed
2419  * @message: debug message to print as "reason"
2420  */
2421 void batadv_tt_global_del_orig(struct batadv_priv *bat_priv,
2422 			       struct batadv_orig_node *orig_node,
2423 			       s32 match_vid,
2424 			       const char *message)
2425 {
2426 	struct batadv_tt_global_entry *tt_global;
2427 	struct batadv_tt_common_entry *tt_common_entry;
2428 	u32 i;
2429 	struct batadv_hashtable *hash = bat_priv->tt.global_hash;
2430 	struct hlist_node *safe;
2431 	struct hlist_head *head;
2432 	spinlock_t *list_lock; /* protects write access to the hash lists */
2433 	unsigned short vid;
2434 
2435 	if (!hash)
2436 		return;
2437 
2438 	for (i = 0; i < hash->size; i++) {
2439 		head = &hash->table[i];
2440 		list_lock = &hash->list_locks[i];
2441 
2442 		spin_lock_bh(list_lock);
2443 		hlist_for_each_entry_safe(tt_common_entry, safe,
2444 					  head, hash_entry) {
2445 			/* remove only matching entries */
2446 			if (match_vid >= 0 && tt_common_entry->vid != match_vid)
2447 				continue;
2448 
2449 			tt_global = container_of(tt_common_entry,
2450 						 struct batadv_tt_global_entry,
2451 						 common);
2452 
2453 			batadv_tt_global_del_orig_node(bat_priv, tt_global,
2454 						       orig_node, message);
2455 
2456 			if (hlist_empty(&tt_global->orig_list)) {
2457 				vid = tt_global->common.vid;
2458 				batadv_dbg(BATADV_DBG_TT, bat_priv,
2459 					   "Deleting global tt entry %pM (vid: %d): %s\n",
2460 					   tt_global->common.addr,
2461 					   batadv_print_vid(vid), message);
2462 				hlist_del_rcu(&tt_common_entry->hash_entry);
2463 				batadv_tt_global_entry_put(tt_global);
2464 			}
2465 		}
2466 		spin_unlock_bh(list_lock);
2467 	}
2468 	clear_bit(BATADV_ORIG_CAPA_HAS_TT, &orig_node->capa_initialized);
2469 }
2470 
2471 static bool batadv_tt_global_to_purge(struct batadv_tt_global_entry *tt_global,
2472 				      char **msg)
2473 {
2474 	bool purge = false;
2475 	unsigned long roam_timeout = BATADV_TT_CLIENT_ROAM_TIMEOUT;
2476 	unsigned long temp_timeout = BATADV_TT_CLIENT_TEMP_TIMEOUT;
2477 
2478 	if ((tt_global->common.flags & BATADV_TT_CLIENT_ROAM) &&
2479 	    batadv_has_timed_out(tt_global->roam_at, roam_timeout)) {
2480 		purge = true;
2481 		*msg = "Roaming timeout\n";
2482 	}
2483 
2484 	if ((tt_global->common.flags & BATADV_TT_CLIENT_TEMP) &&
2485 	    batadv_has_timed_out(tt_global->common.added_at, temp_timeout)) {
2486 		purge = true;
2487 		*msg = "Temporary client timeout\n";
2488 	}
2489 
2490 	return purge;
2491 }
2492 
2493 static void batadv_tt_global_purge(struct batadv_priv *bat_priv)
2494 {
2495 	struct batadv_hashtable *hash = bat_priv->tt.global_hash;
2496 	struct hlist_head *head;
2497 	struct hlist_node *node_tmp;
2498 	spinlock_t *list_lock; /* protects write access to the hash lists */
2499 	u32 i;
2500 	char *msg = NULL;
2501 	struct batadv_tt_common_entry *tt_common;
2502 	struct batadv_tt_global_entry *tt_global;
2503 
2504 	for (i = 0; i < hash->size; i++) {
2505 		head = &hash->table[i];
2506 		list_lock = &hash->list_locks[i];
2507 
2508 		spin_lock_bh(list_lock);
2509 		hlist_for_each_entry_safe(tt_common, node_tmp, head,
2510 					  hash_entry) {
2511 			tt_global = container_of(tt_common,
2512 						 struct batadv_tt_global_entry,
2513 						 common);
2514 
2515 			if (!batadv_tt_global_to_purge(tt_global, &msg))
2516 				continue;
2517 
2518 			batadv_dbg(BATADV_DBG_TT, bat_priv,
2519 				   "Deleting global tt entry %pM (vid: %d): %s\n",
2520 				   tt_global->common.addr,
2521 				   batadv_print_vid(tt_global->common.vid),
2522 				   msg);
2523 
2524 			hlist_del_rcu(&tt_common->hash_entry);
2525 
2526 			batadv_tt_global_entry_put(tt_global);
2527 		}
2528 		spin_unlock_bh(list_lock);
2529 	}
2530 }
2531 
2532 static void batadv_tt_global_table_free(struct batadv_priv *bat_priv)
2533 {
2534 	struct batadv_hashtable *hash;
2535 	spinlock_t *list_lock; /* protects write access to the hash lists */
2536 	struct batadv_tt_common_entry *tt_common_entry;
2537 	struct batadv_tt_global_entry *tt_global;
2538 	struct hlist_node *node_tmp;
2539 	struct hlist_head *head;
2540 	u32 i;
2541 
2542 	if (!bat_priv->tt.global_hash)
2543 		return;
2544 
2545 	hash = bat_priv->tt.global_hash;
2546 
2547 	for (i = 0; i < hash->size; i++) {
2548 		head = &hash->table[i];
2549 		list_lock = &hash->list_locks[i];
2550 
2551 		spin_lock_bh(list_lock);
2552 		hlist_for_each_entry_safe(tt_common_entry, node_tmp,
2553 					  head, hash_entry) {
2554 			hlist_del_rcu(&tt_common_entry->hash_entry);
2555 			tt_global = container_of(tt_common_entry,
2556 						 struct batadv_tt_global_entry,
2557 						 common);
2558 			batadv_tt_global_entry_put(tt_global);
2559 		}
2560 		spin_unlock_bh(list_lock);
2561 	}
2562 
2563 	batadv_hash_destroy(hash);
2564 
2565 	bat_priv->tt.global_hash = NULL;
2566 }
2567 
2568 static bool
2569 _batadv_is_ap_isolated(struct batadv_tt_local_entry *tt_local_entry,
2570 		       struct batadv_tt_global_entry *tt_global_entry)
2571 {
2572 	if (tt_local_entry->common.flags & BATADV_TT_CLIENT_WIFI &&
2573 	    tt_global_entry->common.flags & BATADV_TT_CLIENT_WIFI)
2574 		return true;
2575 
2576 	/* check if the two clients are marked as isolated */
2577 	if (tt_local_entry->common.flags & BATADV_TT_CLIENT_ISOLA &&
2578 	    tt_global_entry->common.flags & BATADV_TT_CLIENT_ISOLA)
2579 		return true;
2580 
2581 	return false;
2582 }
2583 
2584 /**
2585  * batadv_transtable_search() - get the mesh destination for a given client
2586  * @bat_priv: the bat priv with all the soft interface information
2587  * @src: mac address of the source client
2588  * @addr: mac address of the destination client
2589  * @vid: VLAN identifier
2590  *
2591  * Return: a pointer to the originator that was selected as destination in the
2592  * mesh for contacting the client 'addr', NULL otherwise.
2593  * In case of multiple originators serving the same client, the function returns
2594  * the best one (best in terms of metric towards the destination node).
2595  *
2596  * If the two clients are AP isolated the function returns NULL.
2597  */
2598 struct batadv_orig_node *batadv_transtable_search(struct batadv_priv *bat_priv,
2599 						  const u8 *src,
2600 						  const u8 *addr,
2601 						  unsigned short vid)
2602 {
2603 	struct batadv_tt_local_entry *tt_local_entry = NULL;
2604 	struct batadv_tt_global_entry *tt_global_entry = NULL;
2605 	struct batadv_orig_node *orig_node = NULL;
2606 	struct batadv_tt_orig_list_entry *best_entry;
2607 
2608 	if (src && batadv_vlan_ap_isola_get(bat_priv, vid)) {
2609 		tt_local_entry = batadv_tt_local_hash_find(bat_priv, src, vid);
2610 		if (!tt_local_entry ||
2611 		    (tt_local_entry->common.flags & BATADV_TT_CLIENT_PENDING))
2612 			goto out;
2613 	}
2614 
2615 	tt_global_entry = batadv_tt_global_hash_find(bat_priv, addr, vid);
2616 	if (!tt_global_entry)
2617 		goto out;
2618 
2619 	/* check whether the clients should not communicate due to AP
2620 	 * isolation
2621 	 */
2622 	if (tt_local_entry &&
2623 	    _batadv_is_ap_isolated(tt_local_entry, tt_global_entry))
2624 		goto out;
2625 
2626 	rcu_read_lock();
2627 	best_entry = batadv_transtable_best_orig(bat_priv, tt_global_entry);
2628 	/* found anything? */
2629 	if (best_entry)
2630 		orig_node = best_entry->orig_node;
2631 	if (orig_node && !kref_get_unless_zero(&orig_node->refcount))
2632 		orig_node = NULL;
2633 	rcu_read_unlock();
2634 
2635 out:
2636 	if (tt_global_entry)
2637 		batadv_tt_global_entry_put(tt_global_entry);
2638 	if (tt_local_entry)
2639 		batadv_tt_local_entry_put(tt_local_entry);
2640 
2641 	return orig_node;
2642 }
2643 
2644 /**
2645  * batadv_tt_global_crc() - calculates the checksum of the local table belonging
2646  *  to the given orig_node
2647  * @bat_priv: the bat priv with all the soft interface information
2648  * @orig_node: originator for which the CRC should be computed
2649  * @vid: VLAN identifier for which the CRC32 has to be computed
2650  *
2651  * This function computes the checksum for the global table corresponding to a
2652  * specific originator. In particular, the checksum is computed as follows: For
2653  * each client connected to the originator the CRC32C of the MAC address and the
2654  * VID is computed and then all the CRC32Cs of the various clients are xor'ed
2655  * together.
2656  *
2657  * The idea behind is that CRC32C should be used as much as possible in order to
2658  * produce a unique hash of the table, but since the order which is used to feed
2659  * the CRC32C function affects the result and since every node in the network
2660  * probably sorts the clients differently, the hash function cannot be directly
2661  * computed over the entire table. Hence the CRC32C is used only on
2662  * the single client entry, while all the results are then xor'ed together
2663  * because the XOR operation can combine them all while trying to reduce the
2664  * noise as much as possible.
2665  *
2666  * Return: the checksum of the global table of a given originator.
2667  */
2668 static u32 batadv_tt_global_crc(struct batadv_priv *bat_priv,
2669 				struct batadv_orig_node *orig_node,
2670 				unsigned short vid)
2671 {
2672 	struct batadv_hashtable *hash = bat_priv->tt.global_hash;
2673 	struct batadv_tt_orig_list_entry *tt_orig;
2674 	struct batadv_tt_common_entry *tt_common;
2675 	struct batadv_tt_global_entry *tt_global;
2676 	struct hlist_head *head;
2677 	u32 i, crc_tmp, crc = 0;
2678 	u8 flags;
2679 	__be16 tmp_vid;
2680 
2681 	for (i = 0; i < hash->size; i++) {
2682 		head = &hash->table[i];
2683 
2684 		rcu_read_lock();
2685 		hlist_for_each_entry_rcu(tt_common, head, hash_entry) {
2686 			tt_global = container_of(tt_common,
2687 						 struct batadv_tt_global_entry,
2688 						 common);
2689 			/* compute the CRC only for entries belonging to the
2690 			 * VLAN identified by the vid passed as parameter
2691 			 */
2692 			if (tt_common->vid != vid)
2693 				continue;
2694 
2695 			/* Roaming clients are in the global table for
2696 			 * consistency only. They don't have to be
2697 			 * taken into account while computing the
2698 			 * global crc
2699 			 */
2700 			if (tt_common->flags & BATADV_TT_CLIENT_ROAM)
2701 				continue;
2702 			/* Temporary clients have not been announced yet, so
2703 			 * they have to be skipped while computing the global
2704 			 * crc
2705 			 */
2706 			if (tt_common->flags & BATADV_TT_CLIENT_TEMP)
2707 				continue;
2708 
2709 			/* find out if this global entry is announced by this
2710 			 * originator
2711 			 */
2712 			tt_orig = batadv_tt_global_orig_entry_find(tt_global,
2713 								   orig_node);
2714 			if (!tt_orig)
2715 				continue;
2716 
2717 			/* use network order to read the VID: this ensures that
2718 			 * every node reads the bytes in the same order.
2719 			 */
2720 			tmp_vid = htons(tt_common->vid);
2721 			crc_tmp = crc32c(0, &tmp_vid, sizeof(tmp_vid));
2722 
2723 			/* compute the CRC on flags that have to be kept in sync
2724 			 * among nodes
2725 			 */
2726 			flags = tt_orig->flags;
2727 			crc_tmp = crc32c(crc_tmp, &flags, sizeof(flags));
2728 
2729 			crc ^= crc32c(crc_tmp, tt_common->addr, ETH_ALEN);
2730 
2731 			batadv_tt_orig_list_entry_put(tt_orig);
2732 		}
2733 		rcu_read_unlock();
2734 	}
2735 
2736 	return crc;
2737 }
2738 
2739 /**
2740  * batadv_tt_local_crc() - calculates the checksum of the local table
2741  * @bat_priv: the bat priv with all the soft interface information
2742  * @vid: VLAN identifier for which the CRC32 has to be computed
2743  *
2744  * For details about the computation, please refer to the documentation for
2745  * batadv_tt_global_crc().
2746  *
2747  * Return: the checksum of the local table
2748  */
2749 static u32 batadv_tt_local_crc(struct batadv_priv *bat_priv,
2750 			       unsigned short vid)
2751 {
2752 	struct batadv_hashtable *hash = bat_priv->tt.local_hash;
2753 	struct batadv_tt_common_entry *tt_common;
2754 	struct hlist_head *head;
2755 	u32 i, crc_tmp, crc = 0;
2756 	u8 flags;
2757 	__be16 tmp_vid;
2758 
2759 	for (i = 0; i < hash->size; i++) {
2760 		head = &hash->table[i];
2761 
2762 		rcu_read_lock();
2763 		hlist_for_each_entry_rcu(tt_common, head, hash_entry) {
2764 			/* compute the CRC only for entries belonging to the
2765 			 * VLAN identified by vid
2766 			 */
2767 			if (tt_common->vid != vid)
2768 				continue;
2769 
2770 			/* not yet committed clients have not to be taken into
2771 			 * account while computing the CRC
2772 			 */
2773 			if (tt_common->flags & BATADV_TT_CLIENT_NEW)
2774 				continue;
2775 
2776 			/* use network order to read the VID: this ensures that
2777 			 * every node reads the bytes in the same order.
2778 			 */
2779 			tmp_vid = htons(tt_common->vid);
2780 			crc_tmp = crc32c(0, &tmp_vid, sizeof(tmp_vid));
2781 
2782 			/* compute the CRC on flags that have to be kept in sync
2783 			 * among nodes
2784 			 */
2785 			flags = tt_common->flags & BATADV_TT_SYNC_MASK;
2786 			crc_tmp = crc32c(crc_tmp, &flags, sizeof(flags));
2787 
2788 			crc ^= crc32c(crc_tmp, tt_common->addr, ETH_ALEN);
2789 		}
2790 		rcu_read_unlock();
2791 	}
2792 
2793 	return crc;
2794 }
2795 
2796 /**
2797  * batadv_tt_req_node_release() - free tt_req node entry
2798  * @ref: kref pointer of the tt req_node entry
2799  */
2800 static void batadv_tt_req_node_release(struct kref *ref)
2801 {
2802 	struct batadv_tt_req_node *tt_req_node;
2803 
2804 	tt_req_node = container_of(ref, struct batadv_tt_req_node, refcount);
2805 
2806 	kmem_cache_free(batadv_tt_req_cache, tt_req_node);
2807 }
2808 
2809 /**
2810  * batadv_tt_req_node_put() - decrement the tt_req_node refcounter and
2811  *  possibly release it
2812  * @tt_req_node: tt_req_node to be free'd
2813  */
2814 static void batadv_tt_req_node_put(struct batadv_tt_req_node *tt_req_node)
2815 {
2816 	kref_put(&tt_req_node->refcount, batadv_tt_req_node_release);
2817 }
2818 
2819 static void batadv_tt_req_list_free(struct batadv_priv *bat_priv)
2820 {
2821 	struct batadv_tt_req_node *node;
2822 	struct hlist_node *safe;
2823 
2824 	spin_lock_bh(&bat_priv->tt.req_list_lock);
2825 
2826 	hlist_for_each_entry_safe(node, safe, &bat_priv->tt.req_list, list) {
2827 		hlist_del_init(&node->list);
2828 		batadv_tt_req_node_put(node);
2829 	}
2830 
2831 	spin_unlock_bh(&bat_priv->tt.req_list_lock);
2832 }
2833 
2834 static void batadv_tt_save_orig_buffer(struct batadv_priv *bat_priv,
2835 				       struct batadv_orig_node *orig_node,
2836 				       const void *tt_buff,
2837 				       u16 tt_buff_len)
2838 {
2839 	/* Replace the old buffer only if I received something in the
2840 	 * last OGM (the OGM could carry no changes)
2841 	 */
2842 	spin_lock_bh(&orig_node->tt_buff_lock);
2843 	if (tt_buff_len > 0) {
2844 		kfree(orig_node->tt_buff);
2845 		orig_node->tt_buff_len = 0;
2846 		orig_node->tt_buff = kmalloc(tt_buff_len, GFP_ATOMIC);
2847 		if (orig_node->tt_buff) {
2848 			memcpy(orig_node->tt_buff, tt_buff, tt_buff_len);
2849 			orig_node->tt_buff_len = tt_buff_len;
2850 		}
2851 	}
2852 	spin_unlock_bh(&orig_node->tt_buff_lock);
2853 }
2854 
2855 static void batadv_tt_req_purge(struct batadv_priv *bat_priv)
2856 {
2857 	struct batadv_tt_req_node *node;
2858 	struct hlist_node *safe;
2859 
2860 	spin_lock_bh(&bat_priv->tt.req_list_lock);
2861 	hlist_for_each_entry_safe(node, safe, &bat_priv->tt.req_list, list) {
2862 		if (batadv_has_timed_out(node->issued_at,
2863 					 BATADV_TT_REQUEST_TIMEOUT)) {
2864 			hlist_del_init(&node->list);
2865 			batadv_tt_req_node_put(node);
2866 		}
2867 	}
2868 	spin_unlock_bh(&bat_priv->tt.req_list_lock);
2869 }
2870 
2871 /**
2872  * batadv_tt_req_node_new() - search and possibly create a tt_req_node object
2873  * @bat_priv: the bat priv with all the soft interface information
2874  * @orig_node: orig node this request is being issued for
2875  *
2876  * Return: the pointer to the new tt_req_node struct if no request
2877  * has already been issued for this orig_node, NULL otherwise.
2878  */
2879 static struct batadv_tt_req_node *
2880 batadv_tt_req_node_new(struct batadv_priv *bat_priv,
2881 		       struct batadv_orig_node *orig_node)
2882 {
2883 	struct batadv_tt_req_node *tt_req_node_tmp, *tt_req_node = NULL;
2884 
2885 	spin_lock_bh(&bat_priv->tt.req_list_lock);
2886 	hlist_for_each_entry(tt_req_node_tmp, &bat_priv->tt.req_list, list) {
2887 		if (batadv_compare_eth(tt_req_node_tmp, orig_node) &&
2888 		    !batadv_has_timed_out(tt_req_node_tmp->issued_at,
2889 					  BATADV_TT_REQUEST_TIMEOUT))
2890 			goto unlock;
2891 	}
2892 
2893 	tt_req_node = kmem_cache_alloc(batadv_tt_req_cache, GFP_ATOMIC);
2894 	if (!tt_req_node)
2895 		goto unlock;
2896 
2897 	kref_init(&tt_req_node->refcount);
2898 	ether_addr_copy(tt_req_node->addr, orig_node->orig);
2899 	tt_req_node->issued_at = jiffies;
2900 
2901 	kref_get(&tt_req_node->refcount);
2902 	hlist_add_head(&tt_req_node->list, &bat_priv->tt.req_list);
2903 unlock:
2904 	spin_unlock_bh(&bat_priv->tt.req_list_lock);
2905 	return tt_req_node;
2906 }
2907 
2908 /**
2909  * batadv_tt_local_valid() - verify local tt entry and get flags
2910  * @entry_ptr: to be checked local tt entry
2911  * @data_ptr: not used but definition required to satisfy the callback prototype
2912  * @flags: a pointer to store TT flags for this client to
2913  *
2914  * Checks the validity of the given local TT entry. If it is, then the provided
2915  * flags pointer is updated.
2916  *
2917  * Return: true if the entry is a valid, false otherwise.
2918  */
2919 static bool batadv_tt_local_valid(const void *entry_ptr,
2920 				  const void *data_ptr,
2921 				  u8 *flags)
2922 {
2923 	const struct batadv_tt_common_entry *tt_common_entry = entry_ptr;
2924 
2925 	if (tt_common_entry->flags & BATADV_TT_CLIENT_NEW)
2926 		return false;
2927 
2928 	if (flags)
2929 		*flags = tt_common_entry->flags;
2930 
2931 	return true;
2932 }
2933 
2934 /**
2935  * batadv_tt_global_valid() - verify global tt entry and get flags
2936  * @entry_ptr: to be checked global tt entry
2937  * @data_ptr: an orig_node object (may be NULL)
2938  * @flags: a pointer to store TT flags for this client to
2939  *
2940  * Checks the validity of the given global TT entry. If it is, then the provided
2941  * flags pointer is updated either with the common (summed) TT flags if data_ptr
2942  * is NULL or the specific, per originator TT flags otherwise.
2943  *
2944  * Return: true if the entry is a valid, false otherwise.
2945  */
2946 static bool batadv_tt_global_valid(const void *entry_ptr,
2947 				   const void *data_ptr,
2948 				   u8 *flags)
2949 {
2950 	const struct batadv_tt_common_entry *tt_common_entry = entry_ptr;
2951 	const struct batadv_tt_global_entry *tt_global_entry;
2952 	const struct batadv_orig_node *orig_node = data_ptr;
2953 
2954 	if (tt_common_entry->flags & BATADV_TT_CLIENT_ROAM ||
2955 	    tt_common_entry->flags & BATADV_TT_CLIENT_TEMP)
2956 		return false;
2957 
2958 	tt_global_entry = container_of(tt_common_entry,
2959 				       struct batadv_tt_global_entry,
2960 				       common);
2961 
2962 	return batadv_tt_global_entry_has_orig(tt_global_entry, orig_node,
2963 					       flags);
2964 }
2965 
2966 /**
2967  * batadv_tt_tvlv_generate() - fill the tvlv buff with the tt entries from the
2968  *  specified tt hash
2969  * @bat_priv: the bat priv with all the soft interface information
2970  * @hash: hash table containing the tt entries
2971  * @tt_len: expected tvlv tt data buffer length in number of bytes
2972  * @tvlv_buff: pointer to the buffer to fill with the TT data
2973  * @valid_cb: function to filter tt change entries and to return TT flags
2974  * @cb_data: data passed to the filter function as argument
2975  *
2976  * Fills the tvlv buff with the tt entries from the specified hash. If valid_cb
2977  * is not provided then this becomes a no-op.
2978  */
2979 static void batadv_tt_tvlv_generate(struct batadv_priv *bat_priv,
2980 				    struct batadv_hashtable *hash,
2981 				    void *tvlv_buff, u16 tt_len,
2982 				    bool (*valid_cb)(const void *,
2983 						     const void *,
2984 						     u8 *flags),
2985 				    void *cb_data)
2986 {
2987 	struct batadv_tt_common_entry *tt_common_entry;
2988 	struct batadv_tvlv_tt_change *tt_change;
2989 	struct hlist_head *head;
2990 	u16 tt_tot, tt_num_entries = 0;
2991 	u8 flags;
2992 	bool ret;
2993 	u32 i;
2994 
2995 	tt_tot = batadv_tt_entries(tt_len);
2996 	tt_change = (struct batadv_tvlv_tt_change *)tvlv_buff;
2997 
2998 	if (!valid_cb)
2999 		return;
3000 
3001 	rcu_read_lock();
3002 	for (i = 0; i < hash->size; i++) {
3003 		head = &hash->table[i];
3004 
3005 		hlist_for_each_entry_rcu(tt_common_entry,
3006 					 head, hash_entry) {
3007 			if (tt_tot == tt_num_entries)
3008 				break;
3009 
3010 			ret = valid_cb(tt_common_entry, cb_data, &flags);
3011 			if (!ret)
3012 				continue;
3013 
3014 			ether_addr_copy(tt_change->addr, tt_common_entry->addr);
3015 			tt_change->flags = flags;
3016 			tt_change->vid = htons(tt_common_entry->vid);
3017 			memset(tt_change->reserved, 0,
3018 			       sizeof(tt_change->reserved));
3019 
3020 			tt_num_entries++;
3021 			tt_change++;
3022 		}
3023 	}
3024 	rcu_read_unlock();
3025 }
3026 
3027 /**
3028  * batadv_tt_global_check_crc() - check if all the CRCs are correct
3029  * @orig_node: originator for which the CRCs have to be checked
3030  * @tt_vlan: pointer to the first tvlv VLAN entry
3031  * @num_vlan: number of tvlv VLAN entries
3032  *
3033  * Return: true if all the received CRCs match the locally stored ones, false
3034  * otherwise
3035  */
3036 static bool batadv_tt_global_check_crc(struct batadv_orig_node *orig_node,
3037 				       struct batadv_tvlv_tt_vlan_data *tt_vlan,
3038 				       u16 num_vlan)
3039 {
3040 	struct batadv_tvlv_tt_vlan_data *tt_vlan_tmp;
3041 	struct batadv_orig_node_vlan *vlan;
3042 	int i, orig_num_vlan;
3043 	u32 crc;
3044 
3045 	/* check if each received CRC matches the locally stored one */
3046 	for (i = 0; i < num_vlan; i++) {
3047 		tt_vlan_tmp = tt_vlan + i;
3048 
3049 		/* if orig_node is a backbone node for this VLAN, don't check
3050 		 * the CRC as we ignore all the global entries over it
3051 		 */
3052 		if (batadv_bla_is_backbone_gw_orig(orig_node->bat_priv,
3053 						   orig_node->orig,
3054 						   ntohs(tt_vlan_tmp->vid)))
3055 			continue;
3056 
3057 		vlan = batadv_orig_node_vlan_get(orig_node,
3058 						 ntohs(tt_vlan_tmp->vid));
3059 		if (!vlan)
3060 			return false;
3061 
3062 		crc = vlan->tt.crc;
3063 		batadv_orig_node_vlan_put(vlan);
3064 
3065 		if (crc != ntohl(tt_vlan_tmp->crc))
3066 			return false;
3067 	}
3068 
3069 	/* check if any excess VLANs exist locally for the originator
3070 	 * which are not mentioned in the TVLV from the originator.
3071 	 */
3072 	rcu_read_lock();
3073 	orig_num_vlan = 0;
3074 	hlist_for_each_entry_rcu(vlan, &orig_node->vlan_list, list)
3075 		orig_num_vlan++;
3076 	rcu_read_unlock();
3077 
3078 	if (orig_num_vlan > num_vlan)
3079 		return false;
3080 
3081 	return true;
3082 }
3083 
3084 /**
3085  * batadv_tt_local_update_crc() - update all the local CRCs
3086  * @bat_priv: the bat priv with all the soft interface information
3087  */
3088 static void batadv_tt_local_update_crc(struct batadv_priv *bat_priv)
3089 {
3090 	struct batadv_softif_vlan *vlan;
3091 
3092 	/* recompute the global CRC for each VLAN */
3093 	rcu_read_lock();
3094 	hlist_for_each_entry_rcu(vlan, &bat_priv->softif_vlan_list, list) {
3095 		vlan->tt.crc = batadv_tt_local_crc(bat_priv, vlan->vid);
3096 	}
3097 	rcu_read_unlock();
3098 }
3099 
3100 /**
3101  * batadv_tt_global_update_crc() - update all the global CRCs for this orig_node
3102  * @bat_priv: the bat priv with all the soft interface information
3103  * @orig_node: the orig_node for which the CRCs have to be updated
3104  */
3105 static void batadv_tt_global_update_crc(struct batadv_priv *bat_priv,
3106 					struct batadv_orig_node *orig_node)
3107 {
3108 	struct batadv_orig_node_vlan *vlan;
3109 	u32 crc;
3110 
3111 	/* recompute the global CRC for each VLAN */
3112 	rcu_read_lock();
3113 	hlist_for_each_entry_rcu(vlan, &orig_node->vlan_list, list) {
3114 		/* if orig_node is a backbone node for this VLAN, don't compute
3115 		 * the CRC as we ignore all the global entries over it
3116 		 */
3117 		if (batadv_bla_is_backbone_gw_orig(bat_priv, orig_node->orig,
3118 						   vlan->vid))
3119 			continue;
3120 
3121 		crc = batadv_tt_global_crc(bat_priv, orig_node, vlan->vid);
3122 		vlan->tt.crc = crc;
3123 	}
3124 	rcu_read_unlock();
3125 }
3126 
3127 /**
3128  * batadv_send_tt_request() - send a TT Request message to a given node
3129  * @bat_priv: the bat priv with all the soft interface information
3130  * @dst_orig_node: the destination of the message
3131  * @ttvn: the version number that the source of the message is looking for
3132  * @tt_vlan: pointer to the first tvlv VLAN object to request
3133  * @num_vlan: number of tvlv VLAN entries
3134  * @full_table: ask for the entire translation table if true, while only for the
3135  *  last TT diff otherwise
3136  *
3137  * Return: true if the TT Request was sent, false otherwise
3138  */
3139 static bool batadv_send_tt_request(struct batadv_priv *bat_priv,
3140 				   struct batadv_orig_node *dst_orig_node,
3141 				   u8 ttvn,
3142 				   struct batadv_tvlv_tt_vlan_data *tt_vlan,
3143 				   u16 num_vlan, bool full_table)
3144 {
3145 	struct batadv_tvlv_tt_data *tvlv_tt_data = NULL;
3146 	struct batadv_tt_req_node *tt_req_node = NULL;
3147 	struct batadv_tvlv_tt_vlan_data *tt_vlan_req;
3148 	struct batadv_hard_iface *primary_if;
3149 	bool ret = false;
3150 	int i, size;
3151 
3152 	primary_if = batadv_primary_if_get_selected(bat_priv);
3153 	if (!primary_if)
3154 		goto out;
3155 
3156 	/* The new tt_req will be issued only if I'm not waiting for a
3157 	 * reply from the same orig_node yet
3158 	 */
3159 	tt_req_node = batadv_tt_req_node_new(bat_priv, dst_orig_node);
3160 	if (!tt_req_node)
3161 		goto out;
3162 
3163 	size = sizeof(*tvlv_tt_data) + sizeof(*tt_vlan_req) * num_vlan;
3164 	tvlv_tt_data = kzalloc(size, GFP_ATOMIC);
3165 	if (!tvlv_tt_data)
3166 		goto out;
3167 
3168 	tvlv_tt_data->flags = BATADV_TT_REQUEST;
3169 	tvlv_tt_data->ttvn = ttvn;
3170 	tvlv_tt_data->num_vlan = htons(num_vlan);
3171 
3172 	/* send all the CRCs within the request. This is needed by intermediate
3173 	 * nodes to ensure they have the correct table before replying
3174 	 */
3175 	tt_vlan_req = (struct batadv_tvlv_tt_vlan_data *)(tvlv_tt_data + 1);
3176 	for (i = 0; i < num_vlan; i++) {
3177 		tt_vlan_req->vid = tt_vlan->vid;
3178 		tt_vlan_req->crc = tt_vlan->crc;
3179 
3180 		tt_vlan_req++;
3181 		tt_vlan++;
3182 	}
3183 
3184 	if (full_table)
3185 		tvlv_tt_data->flags |= BATADV_TT_FULL_TABLE;
3186 
3187 	batadv_dbg(BATADV_DBG_TT, bat_priv, "Sending TT_REQUEST to %pM [%c]\n",
3188 		   dst_orig_node->orig, full_table ? 'F' : '.');
3189 
3190 	batadv_inc_counter(bat_priv, BATADV_CNT_TT_REQUEST_TX);
3191 	batadv_tvlv_unicast_send(bat_priv, primary_if->net_dev->dev_addr,
3192 				 dst_orig_node->orig, BATADV_TVLV_TT, 1,
3193 				 tvlv_tt_data, size);
3194 	ret = true;
3195 
3196 out:
3197 	if (primary_if)
3198 		batadv_hardif_put(primary_if);
3199 
3200 	if (ret && tt_req_node) {
3201 		spin_lock_bh(&bat_priv->tt.req_list_lock);
3202 		if (!hlist_unhashed(&tt_req_node->list)) {
3203 			hlist_del_init(&tt_req_node->list);
3204 			batadv_tt_req_node_put(tt_req_node);
3205 		}
3206 		spin_unlock_bh(&bat_priv->tt.req_list_lock);
3207 	}
3208 
3209 	if (tt_req_node)
3210 		batadv_tt_req_node_put(tt_req_node);
3211 
3212 	kfree(tvlv_tt_data);
3213 	return ret;
3214 }
3215 
3216 /**
3217  * batadv_send_other_tt_response() - send reply to tt request concerning another
3218  *  node's translation table
3219  * @bat_priv: the bat priv with all the soft interface information
3220  * @tt_data: tt data containing the tt request information
3221  * @req_src: mac address of tt request sender
3222  * @req_dst: mac address of tt request recipient
3223  *
3224  * Return: true if tt request reply was sent, false otherwise.
3225  */
3226 static bool batadv_send_other_tt_response(struct batadv_priv *bat_priv,
3227 					  struct batadv_tvlv_tt_data *tt_data,
3228 					  u8 *req_src, u8 *req_dst)
3229 {
3230 	struct batadv_orig_node *req_dst_orig_node;
3231 	struct batadv_orig_node *res_dst_orig_node = NULL;
3232 	struct batadv_tvlv_tt_change *tt_change;
3233 	struct batadv_tvlv_tt_data *tvlv_tt_data = NULL;
3234 	struct batadv_tvlv_tt_vlan_data *tt_vlan;
3235 	bool ret = false, full_table;
3236 	u8 orig_ttvn, req_ttvn;
3237 	u16 tvlv_len;
3238 	s32 tt_len;
3239 
3240 	batadv_dbg(BATADV_DBG_TT, bat_priv,
3241 		   "Received TT_REQUEST from %pM for ttvn: %u (%pM) [%c]\n",
3242 		   req_src, tt_data->ttvn, req_dst,
3243 		   ((tt_data->flags & BATADV_TT_FULL_TABLE) ? 'F' : '.'));
3244 
3245 	/* Let's get the orig node of the REAL destination */
3246 	req_dst_orig_node = batadv_orig_hash_find(bat_priv, req_dst);
3247 	if (!req_dst_orig_node)
3248 		goto out;
3249 
3250 	res_dst_orig_node = batadv_orig_hash_find(bat_priv, req_src);
3251 	if (!res_dst_orig_node)
3252 		goto out;
3253 
3254 	orig_ttvn = (u8)atomic_read(&req_dst_orig_node->last_ttvn);
3255 	req_ttvn = tt_data->ttvn;
3256 
3257 	tt_vlan = (struct batadv_tvlv_tt_vlan_data *)(tt_data + 1);
3258 	/* this node doesn't have the requested data */
3259 	if (orig_ttvn != req_ttvn ||
3260 	    !batadv_tt_global_check_crc(req_dst_orig_node, tt_vlan,
3261 					ntohs(tt_data->num_vlan)))
3262 		goto out;
3263 
3264 	/* If the full table has been explicitly requested */
3265 	if (tt_data->flags & BATADV_TT_FULL_TABLE ||
3266 	    !req_dst_orig_node->tt_buff)
3267 		full_table = true;
3268 	else
3269 		full_table = false;
3270 
3271 	/* TT fragmentation hasn't been implemented yet, so send as many
3272 	 * TT entries fit a single packet as possible only
3273 	 */
3274 	if (!full_table) {
3275 		spin_lock_bh(&req_dst_orig_node->tt_buff_lock);
3276 		tt_len = req_dst_orig_node->tt_buff_len;
3277 
3278 		tvlv_len = batadv_tt_prepare_tvlv_global_data(req_dst_orig_node,
3279 							      &tvlv_tt_data,
3280 							      &tt_change,
3281 							      &tt_len);
3282 		if (!tt_len)
3283 			goto unlock;
3284 
3285 		/* Copy the last orig_node's OGM buffer */
3286 		memcpy(tt_change, req_dst_orig_node->tt_buff,
3287 		       req_dst_orig_node->tt_buff_len);
3288 		spin_unlock_bh(&req_dst_orig_node->tt_buff_lock);
3289 	} else {
3290 		/* allocate the tvlv, put the tt_data and all the tt_vlan_data
3291 		 * in the initial part
3292 		 */
3293 		tt_len = -1;
3294 		tvlv_len = batadv_tt_prepare_tvlv_global_data(req_dst_orig_node,
3295 							      &tvlv_tt_data,
3296 							      &tt_change,
3297 							      &tt_len);
3298 		if (!tt_len)
3299 			goto out;
3300 
3301 		/* fill the rest of the tvlv with the real TT entries */
3302 		batadv_tt_tvlv_generate(bat_priv, bat_priv->tt.global_hash,
3303 					tt_change, tt_len,
3304 					batadv_tt_global_valid,
3305 					req_dst_orig_node);
3306 	}
3307 
3308 	/* Don't send the response, if larger than fragmented packet. */
3309 	tt_len = sizeof(struct batadv_unicast_tvlv_packet) + tvlv_len;
3310 	if (tt_len > atomic_read(&bat_priv->packet_size_max)) {
3311 		net_ratelimited_function(batadv_info, bat_priv->soft_iface,
3312 					 "Ignoring TT_REQUEST from %pM; Response size exceeds max packet size.\n",
3313 					 res_dst_orig_node->orig);
3314 		goto out;
3315 	}
3316 
3317 	tvlv_tt_data->flags = BATADV_TT_RESPONSE;
3318 	tvlv_tt_data->ttvn = req_ttvn;
3319 
3320 	if (full_table)
3321 		tvlv_tt_data->flags |= BATADV_TT_FULL_TABLE;
3322 
3323 	batadv_dbg(BATADV_DBG_TT, bat_priv,
3324 		   "Sending TT_RESPONSE %pM for %pM [%c] (ttvn: %u)\n",
3325 		   res_dst_orig_node->orig, req_dst_orig_node->orig,
3326 		   full_table ? 'F' : '.', req_ttvn);
3327 
3328 	batadv_inc_counter(bat_priv, BATADV_CNT_TT_RESPONSE_TX);
3329 
3330 	batadv_tvlv_unicast_send(bat_priv, req_dst_orig_node->orig,
3331 				 req_src, BATADV_TVLV_TT, 1, tvlv_tt_data,
3332 				 tvlv_len);
3333 
3334 	ret = true;
3335 	goto out;
3336 
3337 unlock:
3338 	spin_unlock_bh(&req_dst_orig_node->tt_buff_lock);
3339 
3340 out:
3341 	if (res_dst_orig_node)
3342 		batadv_orig_node_put(res_dst_orig_node);
3343 	if (req_dst_orig_node)
3344 		batadv_orig_node_put(req_dst_orig_node);
3345 	kfree(tvlv_tt_data);
3346 	return ret;
3347 }
3348 
3349 /**
3350  * batadv_send_my_tt_response() - send reply to tt request concerning this
3351  *  node's translation table
3352  * @bat_priv: the bat priv with all the soft interface information
3353  * @tt_data: tt data containing the tt request information
3354  * @req_src: mac address of tt request sender
3355  *
3356  * Return: true if tt request reply was sent, false otherwise.
3357  */
3358 static bool batadv_send_my_tt_response(struct batadv_priv *bat_priv,
3359 				       struct batadv_tvlv_tt_data *tt_data,
3360 				       u8 *req_src)
3361 {
3362 	struct batadv_tvlv_tt_data *tvlv_tt_data = NULL;
3363 	struct batadv_hard_iface *primary_if = NULL;
3364 	struct batadv_tvlv_tt_change *tt_change;
3365 	struct batadv_orig_node *orig_node;
3366 	u8 my_ttvn, req_ttvn;
3367 	u16 tvlv_len;
3368 	bool full_table;
3369 	s32 tt_len;
3370 
3371 	batadv_dbg(BATADV_DBG_TT, bat_priv,
3372 		   "Received TT_REQUEST from %pM for ttvn: %u (me) [%c]\n",
3373 		   req_src, tt_data->ttvn,
3374 		   ((tt_data->flags & BATADV_TT_FULL_TABLE) ? 'F' : '.'));
3375 
3376 	spin_lock_bh(&bat_priv->tt.commit_lock);
3377 
3378 	my_ttvn = (u8)atomic_read(&bat_priv->tt.vn);
3379 	req_ttvn = tt_data->ttvn;
3380 
3381 	orig_node = batadv_orig_hash_find(bat_priv, req_src);
3382 	if (!orig_node)
3383 		goto out;
3384 
3385 	primary_if = batadv_primary_if_get_selected(bat_priv);
3386 	if (!primary_if)
3387 		goto out;
3388 
3389 	/* If the full table has been explicitly requested or the gap
3390 	 * is too big send the whole local translation table
3391 	 */
3392 	if (tt_data->flags & BATADV_TT_FULL_TABLE || my_ttvn != req_ttvn ||
3393 	    !bat_priv->tt.last_changeset)
3394 		full_table = true;
3395 	else
3396 		full_table = false;
3397 
3398 	/* TT fragmentation hasn't been implemented yet, so send as many
3399 	 * TT entries fit a single packet as possible only
3400 	 */
3401 	if (!full_table) {
3402 		spin_lock_bh(&bat_priv->tt.last_changeset_lock);
3403 
3404 		tt_len = bat_priv->tt.last_changeset_len;
3405 		tvlv_len = batadv_tt_prepare_tvlv_local_data(bat_priv,
3406 							     &tvlv_tt_data,
3407 							     &tt_change,
3408 							     &tt_len);
3409 		if (!tt_len || !tvlv_len)
3410 			goto unlock;
3411 
3412 		/* Copy the last orig_node's OGM buffer */
3413 		memcpy(tt_change, bat_priv->tt.last_changeset,
3414 		       bat_priv->tt.last_changeset_len);
3415 		spin_unlock_bh(&bat_priv->tt.last_changeset_lock);
3416 	} else {
3417 		req_ttvn = (u8)atomic_read(&bat_priv->tt.vn);
3418 
3419 		/* allocate the tvlv, put the tt_data and all the tt_vlan_data
3420 		 * in the initial part
3421 		 */
3422 		tt_len = -1;
3423 		tvlv_len = batadv_tt_prepare_tvlv_local_data(bat_priv,
3424 							     &tvlv_tt_data,
3425 							     &tt_change,
3426 							     &tt_len);
3427 		if (!tt_len || !tvlv_len)
3428 			goto out;
3429 
3430 		/* fill the rest of the tvlv with the real TT entries */
3431 		batadv_tt_tvlv_generate(bat_priv, bat_priv->tt.local_hash,
3432 					tt_change, tt_len,
3433 					batadv_tt_local_valid, NULL);
3434 	}
3435 
3436 	tvlv_tt_data->flags = BATADV_TT_RESPONSE;
3437 	tvlv_tt_data->ttvn = req_ttvn;
3438 
3439 	if (full_table)
3440 		tvlv_tt_data->flags |= BATADV_TT_FULL_TABLE;
3441 
3442 	batadv_dbg(BATADV_DBG_TT, bat_priv,
3443 		   "Sending TT_RESPONSE to %pM [%c] (ttvn: %u)\n",
3444 		   orig_node->orig, full_table ? 'F' : '.', req_ttvn);
3445 
3446 	batadv_inc_counter(bat_priv, BATADV_CNT_TT_RESPONSE_TX);
3447 
3448 	batadv_tvlv_unicast_send(bat_priv, primary_if->net_dev->dev_addr,
3449 				 req_src, BATADV_TVLV_TT, 1, tvlv_tt_data,
3450 				 tvlv_len);
3451 
3452 	goto out;
3453 
3454 unlock:
3455 	spin_unlock_bh(&bat_priv->tt.last_changeset_lock);
3456 out:
3457 	spin_unlock_bh(&bat_priv->tt.commit_lock);
3458 	if (orig_node)
3459 		batadv_orig_node_put(orig_node);
3460 	if (primary_if)
3461 		batadv_hardif_put(primary_if);
3462 	kfree(tvlv_tt_data);
3463 	/* The packet was for this host, so it doesn't need to be re-routed */
3464 	return true;
3465 }
3466 
3467 /**
3468  * batadv_send_tt_response() - send reply to tt request
3469  * @bat_priv: the bat priv with all the soft interface information
3470  * @tt_data: tt data containing the tt request information
3471  * @req_src: mac address of tt request sender
3472  * @req_dst: mac address of tt request recipient
3473  *
3474  * Return: true if tt request reply was sent, false otherwise.
3475  */
3476 static bool batadv_send_tt_response(struct batadv_priv *bat_priv,
3477 				    struct batadv_tvlv_tt_data *tt_data,
3478 				    u8 *req_src, u8 *req_dst)
3479 {
3480 	if (batadv_is_my_mac(bat_priv, req_dst))
3481 		return batadv_send_my_tt_response(bat_priv, tt_data, req_src);
3482 	return batadv_send_other_tt_response(bat_priv, tt_data, req_src,
3483 					     req_dst);
3484 }
3485 
3486 static void _batadv_tt_update_changes(struct batadv_priv *bat_priv,
3487 				      struct batadv_orig_node *orig_node,
3488 				      struct batadv_tvlv_tt_change *tt_change,
3489 				      u16 tt_num_changes, u8 ttvn)
3490 {
3491 	int i;
3492 	int roams;
3493 
3494 	for (i = 0; i < tt_num_changes; i++) {
3495 		if ((tt_change + i)->flags & BATADV_TT_CLIENT_DEL) {
3496 			roams = (tt_change + i)->flags & BATADV_TT_CLIENT_ROAM;
3497 			batadv_tt_global_del(bat_priv, orig_node,
3498 					     (tt_change + i)->addr,
3499 					     ntohs((tt_change + i)->vid),
3500 					     "tt removed by changes",
3501 					     roams);
3502 		} else {
3503 			if (!batadv_tt_global_add(bat_priv, orig_node,
3504 						  (tt_change + i)->addr,
3505 						  ntohs((tt_change + i)->vid),
3506 						  (tt_change + i)->flags, ttvn))
3507 				/* In case of problem while storing a
3508 				 * global_entry, we stop the updating
3509 				 * procedure without committing the
3510 				 * ttvn change. This will avoid to send
3511 				 * corrupted data on tt_request
3512 				 */
3513 				return;
3514 		}
3515 	}
3516 	set_bit(BATADV_ORIG_CAPA_HAS_TT, &orig_node->capa_initialized);
3517 }
3518 
3519 static void batadv_tt_fill_gtable(struct batadv_priv *bat_priv,
3520 				  struct batadv_tvlv_tt_change *tt_change,
3521 				  u8 ttvn, u8 *resp_src,
3522 				  u16 num_entries)
3523 {
3524 	struct batadv_orig_node *orig_node;
3525 
3526 	orig_node = batadv_orig_hash_find(bat_priv, resp_src);
3527 	if (!orig_node)
3528 		goto out;
3529 
3530 	/* Purge the old table first.. */
3531 	batadv_tt_global_del_orig(bat_priv, orig_node, -1,
3532 				  "Received full table");
3533 
3534 	_batadv_tt_update_changes(bat_priv, orig_node, tt_change, num_entries,
3535 				  ttvn);
3536 
3537 	spin_lock_bh(&orig_node->tt_buff_lock);
3538 	kfree(orig_node->tt_buff);
3539 	orig_node->tt_buff_len = 0;
3540 	orig_node->tt_buff = NULL;
3541 	spin_unlock_bh(&orig_node->tt_buff_lock);
3542 
3543 	atomic_set(&orig_node->last_ttvn, ttvn);
3544 
3545 out:
3546 	if (orig_node)
3547 		batadv_orig_node_put(orig_node);
3548 }
3549 
3550 static void batadv_tt_update_changes(struct batadv_priv *bat_priv,
3551 				     struct batadv_orig_node *orig_node,
3552 				     u16 tt_num_changes, u8 ttvn,
3553 				     struct batadv_tvlv_tt_change *tt_change)
3554 {
3555 	_batadv_tt_update_changes(bat_priv, orig_node, tt_change,
3556 				  tt_num_changes, ttvn);
3557 
3558 	batadv_tt_save_orig_buffer(bat_priv, orig_node, tt_change,
3559 				   batadv_tt_len(tt_num_changes));
3560 	atomic_set(&orig_node->last_ttvn, ttvn);
3561 }
3562 
3563 /**
3564  * batadv_is_my_client() - check if a client is served by the local node
3565  * @bat_priv: the bat priv with all the soft interface information
3566  * @addr: the mac address of the client to check
3567  * @vid: VLAN identifier
3568  *
3569  * Return: true if the client is served by this node, false otherwise.
3570  */
3571 bool batadv_is_my_client(struct batadv_priv *bat_priv, const u8 *addr,
3572 			 unsigned short vid)
3573 {
3574 	struct batadv_tt_local_entry *tt_local_entry;
3575 	bool ret = false;
3576 
3577 	tt_local_entry = batadv_tt_local_hash_find(bat_priv, addr, vid);
3578 	if (!tt_local_entry)
3579 		goto out;
3580 	/* Check if the client has been logically deleted (but is kept for
3581 	 * consistency purpose)
3582 	 */
3583 	if ((tt_local_entry->common.flags & BATADV_TT_CLIENT_PENDING) ||
3584 	    (tt_local_entry->common.flags & BATADV_TT_CLIENT_ROAM))
3585 		goto out;
3586 	ret = true;
3587 out:
3588 	if (tt_local_entry)
3589 		batadv_tt_local_entry_put(tt_local_entry);
3590 	return ret;
3591 }
3592 
3593 /**
3594  * batadv_handle_tt_response() - process incoming tt reply
3595  * @bat_priv: the bat priv with all the soft interface information
3596  * @tt_data: tt data containing the tt request information
3597  * @resp_src: mac address of tt reply sender
3598  * @num_entries: number of tt change entries appended to the tt data
3599  */
3600 static void batadv_handle_tt_response(struct batadv_priv *bat_priv,
3601 				      struct batadv_tvlv_tt_data *tt_data,
3602 				      u8 *resp_src, u16 num_entries)
3603 {
3604 	struct batadv_tt_req_node *node;
3605 	struct hlist_node *safe;
3606 	struct batadv_orig_node *orig_node = NULL;
3607 	struct batadv_tvlv_tt_change *tt_change;
3608 	u8 *tvlv_ptr = (u8 *)tt_data;
3609 	u16 change_offset;
3610 
3611 	batadv_dbg(BATADV_DBG_TT, bat_priv,
3612 		   "Received TT_RESPONSE from %pM for ttvn %d t_size: %d [%c]\n",
3613 		   resp_src, tt_data->ttvn, num_entries,
3614 		   ((tt_data->flags & BATADV_TT_FULL_TABLE) ? 'F' : '.'));
3615 
3616 	orig_node = batadv_orig_hash_find(bat_priv, resp_src);
3617 	if (!orig_node)
3618 		goto out;
3619 
3620 	spin_lock_bh(&orig_node->tt_lock);
3621 
3622 	change_offset = sizeof(struct batadv_tvlv_tt_vlan_data);
3623 	change_offset *= ntohs(tt_data->num_vlan);
3624 	change_offset += sizeof(*tt_data);
3625 	tvlv_ptr += change_offset;
3626 
3627 	tt_change = (struct batadv_tvlv_tt_change *)tvlv_ptr;
3628 	if (tt_data->flags & BATADV_TT_FULL_TABLE) {
3629 		batadv_tt_fill_gtable(bat_priv, tt_change, tt_data->ttvn,
3630 				      resp_src, num_entries);
3631 	} else {
3632 		batadv_tt_update_changes(bat_priv, orig_node, num_entries,
3633 					 tt_data->ttvn, tt_change);
3634 	}
3635 
3636 	/* Recalculate the CRC for this orig_node and store it */
3637 	batadv_tt_global_update_crc(bat_priv, orig_node);
3638 
3639 	spin_unlock_bh(&orig_node->tt_lock);
3640 
3641 	/* Delete the tt_req_node from pending tt_requests list */
3642 	spin_lock_bh(&bat_priv->tt.req_list_lock);
3643 	hlist_for_each_entry_safe(node, safe, &bat_priv->tt.req_list, list) {
3644 		if (!batadv_compare_eth(node->addr, resp_src))
3645 			continue;
3646 		hlist_del_init(&node->list);
3647 		batadv_tt_req_node_put(node);
3648 	}
3649 
3650 	spin_unlock_bh(&bat_priv->tt.req_list_lock);
3651 out:
3652 	if (orig_node)
3653 		batadv_orig_node_put(orig_node);
3654 }
3655 
3656 static void batadv_tt_roam_list_free(struct batadv_priv *bat_priv)
3657 {
3658 	struct batadv_tt_roam_node *node, *safe;
3659 
3660 	spin_lock_bh(&bat_priv->tt.roam_list_lock);
3661 
3662 	list_for_each_entry_safe(node, safe, &bat_priv->tt.roam_list, list) {
3663 		list_del(&node->list);
3664 		kmem_cache_free(batadv_tt_roam_cache, node);
3665 	}
3666 
3667 	spin_unlock_bh(&bat_priv->tt.roam_list_lock);
3668 }
3669 
3670 static void batadv_tt_roam_purge(struct batadv_priv *bat_priv)
3671 {
3672 	struct batadv_tt_roam_node *node, *safe;
3673 
3674 	spin_lock_bh(&bat_priv->tt.roam_list_lock);
3675 	list_for_each_entry_safe(node, safe, &bat_priv->tt.roam_list, list) {
3676 		if (!batadv_has_timed_out(node->first_time,
3677 					  BATADV_ROAMING_MAX_TIME))
3678 			continue;
3679 
3680 		list_del(&node->list);
3681 		kmem_cache_free(batadv_tt_roam_cache, node);
3682 	}
3683 	spin_unlock_bh(&bat_priv->tt.roam_list_lock);
3684 }
3685 
3686 /**
3687  * batadv_tt_check_roam_count() - check if a client has roamed too frequently
3688  * @bat_priv: the bat priv with all the soft interface information
3689  * @client: mac address of the roaming client
3690  *
3691  * This function checks whether the client already reached the
3692  * maximum number of possible roaming phases. In this case the ROAMING_ADV
3693  * will not be sent.
3694  *
3695  * Return: true if the ROAMING_ADV can be sent, false otherwise
3696  */
3697 static bool batadv_tt_check_roam_count(struct batadv_priv *bat_priv, u8 *client)
3698 {
3699 	struct batadv_tt_roam_node *tt_roam_node;
3700 	bool ret = false;
3701 
3702 	spin_lock_bh(&bat_priv->tt.roam_list_lock);
3703 	/* The new tt_req will be issued only if I'm not waiting for a
3704 	 * reply from the same orig_node yet
3705 	 */
3706 	list_for_each_entry(tt_roam_node, &bat_priv->tt.roam_list, list) {
3707 		if (!batadv_compare_eth(tt_roam_node->addr, client))
3708 			continue;
3709 
3710 		if (batadv_has_timed_out(tt_roam_node->first_time,
3711 					 BATADV_ROAMING_MAX_TIME))
3712 			continue;
3713 
3714 		if (!batadv_atomic_dec_not_zero(&tt_roam_node->counter))
3715 			/* Sorry, you roamed too many times! */
3716 			goto unlock;
3717 		ret = true;
3718 		break;
3719 	}
3720 
3721 	if (!ret) {
3722 		tt_roam_node = kmem_cache_alloc(batadv_tt_roam_cache,
3723 						GFP_ATOMIC);
3724 		if (!tt_roam_node)
3725 			goto unlock;
3726 
3727 		tt_roam_node->first_time = jiffies;
3728 		atomic_set(&tt_roam_node->counter,
3729 			   BATADV_ROAMING_MAX_COUNT - 1);
3730 		ether_addr_copy(tt_roam_node->addr, client);
3731 
3732 		list_add(&tt_roam_node->list, &bat_priv->tt.roam_list);
3733 		ret = true;
3734 	}
3735 
3736 unlock:
3737 	spin_unlock_bh(&bat_priv->tt.roam_list_lock);
3738 	return ret;
3739 }
3740 
3741 /**
3742  * batadv_send_roam_adv() - send a roaming advertisement message
3743  * @bat_priv: the bat priv with all the soft interface information
3744  * @client: mac address of the roaming client
3745  * @vid: VLAN identifier
3746  * @orig_node: message destination
3747  *
3748  * Send a ROAMING_ADV message to the node which was previously serving this
3749  * client. This is done to inform the node that from now on all traffic destined
3750  * for this particular roamed client has to be forwarded to the sender of the
3751  * roaming message.
3752  */
3753 static void batadv_send_roam_adv(struct batadv_priv *bat_priv, u8 *client,
3754 				 unsigned short vid,
3755 				 struct batadv_orig_node *orig_node)
3756 {
3757 	struct batadv_hard_iface *primary_if;
3758 	struct batadv_tvlv_roam_adv tvlv_roam;
3759 
3760 	primary_if = batadv_primary_if_get_selected(bat_priv);
3761 	if (!primary_if)
3762 		goto out;
3763 
3764 	/* before going on we have to check whether the client has
3765 	 * already roamed to us too many times
3766 	 */
3767 	if (!batadv_tt_check_roam_count(bat_priv, client))
3768 		goto out;
3769 
3770 	batadv_dbg(BATADV_DBG_TT, bat_priv,
3771 		   "Sending ROAMING_ADV to %pM (client %pM, vid: %d)\n",
3772 		   orig_node->orig, client, batadv_print_vid(vid));
3773 
3774 	batadv_inc_counter(bat_priv, BATADV_CNT_TT_ROAM_ADV_TX);
3775 
3776 	memcpy(tvlv_roam.client, client, sizeof(tvlv_roam.client));
3777 	tvlv_roam.vid = htons(vid);
3778 
3779 	batadv_tvlv_unicast_send(bat_priv, primary_if->net_dev->dev_addr,
3780 				 orig_node->orig, BATADV_TVLV_ROAM, 1,
3781 				 &tvlv_roam, sizeof(tvlv_roam));
3782 
3783 out:
3784 	if (primary_if)
3785 		batadv_hardif_put(primary_if);
3786 }
3787 
3788 static void batadv_tt_purge(struct work_struct *work)
3789 {
3790 	struct delayed_work *delayed_work;
3791 	struct batadv_priv_tt *priv_tt;
3792 	struct batadv_priv *bat_priv;
3793 
3794 	delayed_work = to_delayed_work(work);
3795 	priv_tt = container_of(delayed_work, struct batadv_priv_tt, work);
3796 	bat_priv = container_of(priv_tt, struct batadv_priv, tt);
3797 
3798 	batadv_tt_local_purge(bat_priv, BATADV_TT_LOCAL_TIMEOUT);
3799 	batadv_tt_global_purge(bat_priv);
3800 	batadv_tt_req_purge(bat_priv);
3801 	batadv_tt_roam_purge(bat_priv);
3802 
3803 	queue_delayed_work(batadv_event_workqueue, &bat_priv->tt.work,
3804 			   msecs_to_jiffies(BATADV_TT_WORK_PERIOD));
3805 }
3806 
3807 /**
3808  * batadv_tt_free() - Free translation table of soft interface
3809  * @bat_priv: the bat priv with all the soft interface information
3810  */
3811 void batadv_tt_free(struct batadv_priv *bat_priv)
3812 {
3813 	batadv_tvlv_container_unregister(bat_priv, BATADV_TVLV_TT, 1);
3814 	batadv_tvlv_handler_unregister(bat_priv, BATADV_TVLV_TT, 1);
3815 
3816 	cancel_delayed_work_sync(&bat_priv->tt.work);
3817 
3818 	batadv_tt_local_table_free(bat_priv);
3819 	batadv_tt_global_table_free(bat_priv);
3820 	batadv_tt_req_list_free(bat_priv);
3821 	batadv_tt_changes_list_free(bat_priv);
3822 	batadv_tt_roam_list_free(bat_priv);
3823 
3824 	kfree(bat_priv->tt.last_changeset);
3825 }
3826 
3827 /**
3828  * batadv_tt_local_set_flags() - set or unset the specified flags on the local
3829  *  table and possibly count them in the TT size
3830  * @bat_priv: the bat priv with all the soft interface information
3831  * @flags: the flag to switch
3832  * @enable: whether to set or unset the flag
3833  * @count: whether to increase the TT size by the number of changed entries
3834  */
3835 static void batadv_tt_local_set_flags(struct batadv_priv *bat_priv, u16 flags,
3836 				      bool enable, bool count)
3837 {
3838 	struct batadv_hashtable *hash = bat_priv->tt.local_hash;
3839 	struct batadv_tt_common_entry *tt_common_entry;
3840 	struct hlist_head *head;
3841 	u32 i;
3842 
3843 	if (!hash)
3844 		return;
3845 
3846 	for (i = 0; i < hash->size; i++) {
3847 		head = &hash->table[i];
3848 
3849 		rcu_read_lock();
3850 		hlist_for_each_entry_rcu(tt_common_entry,
3851 					 head, hash_entry) {
3852 			if (enable) {
3853 				if ((tt_common_entry->flags & flags) == flags)
3854 					continue;
3855 				tt_common_entry->flags |= flags;
3856 			} else {
3857 				if (!(tt_common_entry->flags & flags))
3858 					continue;
3859 				tt_common_entry->flags &= ~flags;
3860 			}
3861 
3862 			if (!count)
3863 				continue;
3864 
3865 			batadv_tt_local_size_inc(bat_priv,
3866 						 tt_common_entry->vid);
3867 		}
3868 		rcu_read_unlock();
3869 	}
3870 }
3871 
3872 /* Purge out all the tt local entries marked with BATADV_TT_CLIENT_PENDING */
3873 static void batadv_tt_local_purge_pending_clients(struct batadv_priv *bat_priv)
3874 {
3875 	struct batadv_hashtable *hash = bat_priv->tt.local_hash;
3876 	struct batadv_tt_common_entry *tt_common;
3877 	struct batadv_tt_local_entry *tt_local;
3878 	struct hlist_node *node_tmp;
3879 	struct hlist_head *head;
3880 	spinlock_t *list_lock; /* protects write access to the hash lists */
3881 	u32 i;
3882 
3883 	if (!hash)
3884 		return;
3885 
3886 	for (i = 0; i < hash->size; i++) {
3887 		head = &hash->table[i];
3888 		list_lock = &hash->list_locks[i];
3889 
3890 		spin_lock_bh(list_lock);
3891 		hlist_for_each_entry_safe(tt_common, node_tmp, head,
3892 					  hash_entry) {
3893 			if (!(tt_common->flags & BATADV_TT_CLIENT_PENDING))
3894 				continue;
3895 
3896 			batadv_dbg(BATADV_DBG_TT, bat_priv,
3897 				   "Deleting local tt entry (%pM, vid: %d): pending\n",
3898 				   tt_common->addr,
3899 				   batadv_print_vid(tt_common->vid));
3900 
3901 			batadv_tt_local_size_dec(bat_priv, tt_common->vid);
3902 			hlist_del_rcu(&tt_common->hash_entry);
3903 			tt_local = container_of(tt_common,
3904 						struct batadv_tt_local_entry,
3905 						common);
3906 
3907 			batadv_tt_local_entry_put(tt_local);
3908 		}
3909 		spin_unlock_bh(list_lock);
3910 	}
3911 }
3912 
3913 /**
3914  * batadv_tt_local_commit_changes_nolock() - commit all pending local tt changes
3915  *  which have been queued in the time since the last commit
3916  * @bat_priv: the bat priv with all the soft interface information
3917  *
3918  * Caller must hold tt->commit_lock.
3919  */
3920 static void batadv_tt_local_commit_changes_nolock(struct batadv_priv *bat_priv)
3921 {
3922 	lockdep_assert_held(&bat_priv->tt.commit_lock);
3923 
3924 	if (atomic_read(&bat_priv->tt.local_changes) < 1) {
3925 		if (!batadv_atomic_dec_not_zero(&bat_priv->tt.ogm_append_cnt))
3926 			batadv_tt_tvlv_container_update(bat_priv);
3927 		return;
3928 	}
3929 
3930 	batadv_tt_local_set_flags(bat_priv, BATADV_TT_CLIENT_NEW, false, true);
3931 
3932 	batadv_tt_local_purge_pending_clients(bat_priv);
3933 	batadv_tt_local_update_crc(bat_priv);
3934 
3935 	/* Increment the TTVN only once per OGM interval */
3936 	atomic_inc(&bat_priv->tt.vn);
3937 	batadv_dbg(BATADV_DBG_TT, bat_priv,
3938 		   "Local changes committed, updating to ttvn %u\n",
3939 		   (u8)atomic_read(&bat_priv->tt.vn));
3940 
3941 	/* reset the sending counter */
3942 	atomic_set(&bat_priv->tt.ogm_append_cnt, BATADV_TT_OGM_APPEND_MAX);
3943 	batadv_tt_tvlv_container_update(bat_priv);
3944 }
3945 
3946 /**
3947  * batadv_tt_local_commit_changes() - commit all pending local tt changes which
3948  *  have been queued in the time since the last commit
3949  * @bat_priv: the bat priv with all the soft interface information
3950  */
3951 void batadv_tt_local_commit_changes(struct batadv_priv *bat_priv)
3952 {
3953 	spin_lock_bh(&bat_priv->tt.commit_lock);
3954 	batadv_tt_local_commit_changes_nolock(bat_priv);
3955 	spin_unlock_bh(&bat_priv->tt.commit_lock);
3956 }
3957 
3958 /**
3959  * batadv_is_ap_isolated() - Check if packet from upper layer should be dropped
3960  * @bat_priv: the bat priv with all the soft interface information
3961  * @src: source mac address of packet
3962  * @dst: destination mac address of packet
3963  * @vid: vlan id of packet
3964  *
3965  * Return: true when src+dst(+vid) pair should be isolated, false otherwise
3966  */
3967 bool batadv_is_ap_isolated(struct batadv_priv *bat_priv, u8 *src, u8 *dst,
3968 			   unsigned short vid)
3969 {
3970 	struct batadv_tt_local_entry *tt_local_entry;
3971 	struct batadv_tt_global_entry *tt_global_entry;
3972 	struct batadv_softif_vlan *vlan;
3973 	bool ret = false;
3974 
3975 	vlan = batadv_softif_vlan_get(bat_priv, vid);
3976 	if (!vlan)
3977 		return false;
3978 
3979 	if (!atomic_read(&vlan->ap_isolation))
3980 		goto vlan_put;
3981 
3982 	tt_local_entry = batadv_tt_local_hash_find(bat_priv, dst, vid);
3983 	if (!tt_local_entry)
3984 		goto vlan_put;
3985 
3986 	tt_global_entry = batadv_tt_global_hash_find(bat_priv, src, vid);
3987 	if (!tt_global_entry)
3988 		goto local_entry_put;
3989 
3990 	if (_batadv_is_ap_isolated(tt_local_entry, tt_global_entry))
3991 		ret = true;
3992 
3993 	batadv_tt_global_entry_put(tt_global_entry);
3994 local_entry_put:
3995 	batadv_tt_local_entry_put(tt_local_entry);
3996 vlan_put:
3997 	batadv_softif_vlan_put(vlan);
3998 	return ret;
3999 }
4000 
4001 /**
4002  * batadv_tt_update_orig() - update global translation table with new tt
4003  *  information received via ogms
4004  * @bat_priv: the bat priv with all the soft interface information
4005  * @orig_node: the orig_node of the ogm
4006  * @tt_buff: pointer to the first tvlv VLAN entry
4007  * @tt_num_vlan: number of tvlv VLAN entries
4008  * @tt_change: pointer to the first entry in the TT buffer
4009  * @tt_num_changes: number of tt changes inside the tt buffer
4010  * @ttvn: translation table version number of this changeset
4011  */
4012 static void batadv_tt_update_orig(struct batadv_priv *bat_priv,
4013 				  struct batadv_orig_node *orig_node,
4014 				  const void *tt_buff, u16 tt_num_vlan,
4015 				  struct batadv_tvlv_tt_change *tt_change,
4016 				  u16 tt_num_changes, u8 ttvn)
4017 {
4018 	u8 orig_ttvn = (u8)atomic_read(&orig_node->last_ttvn);
4019 	struct batadv_tvlv_tt_vlan_data *tt_vlan;
4020 	bool full_table = true;
4021 	bool has_tt_init;
4022 
4023 	tt_vlan = (struct batadv_tvlv_tt_vlan_data *)tt_buff;
4024 	has_tt_init = test_bit(BATADV_ORIG_CAPA_HAS_TT,
4025 			       &orig_node->capa_initialized);
4026 
4027 	/* orig table not initialised AND first diff is in the OGM OR the ttvn
4028 	 * increased by one -> we can apply the attached changes
4029 	 */
4030 	if ((!has_tt_init && ttvn == 1) || ttvn - orig_ttvn == 1) {
4031 		/* the OGM could not contain the changes due to their size or
4032 		 * because they have already been sent BATADV_TT_OGM_APPEND_MAX
4033 		 * times.
4034 		 * In this case send a tt request
4035 		 */
4036 		if (!tt_num_changes) {
4037 			full_table = false;
4038 			goto request_table;
4039 		}
4040 
4041 		spin_lock_bh(&orig_node->tt_lock);
4042 
4043 		batadv_tt_update_changes(bat_priv, orig_node, tt_num_changes,
4044 					 ttvn, tt_change);
4045 
4046 		/* Even if we received the precomputed crc with the OGM, we
4047 		 * prefer to recompute it to spot any possible inconsistency
4048 		 * in the global table
4049 		 */
4050 		batadv_tt_global_update_crc(bat_priv, orig_node);
4051 
4052 		spin_unlock_bh(&orig_node->tt_lock);
4053 
4054 		/* The ttvn alone is not enough to guarantee consistency
4055 		 * because a single value could represent different states
4056 		 * (due to the wrap around). Thus a node has to check whether
4057 		 * the resulting table (after applying the changes) is still
4058 		 * consistent or not. E.g. a node could disconnect while its
4059 		 * ttvn is X and reconnect on ttvn = X + TTVN_MAX: in this case
4060 		 * checking the CRC value is mandatory to detect the
4061 		 * inconsistency
4062 		 */
4063 		if (!batadv_tt_global_check_crc(orig_node, tt_vlan,
4064 						tt_num_vlan))
4065 			goto request_table;
4066 	} else {
4067 		/* if we missed more than one change or our tables are not
4068 		 * in sync anymore -> request fresh tt data
4069 		 */
4070 		if (!has_tt_init || ttvn != orig_ttvn ||
4071 		    !batadv_tt_global_check_crc(orig_node, tt_vlan,
4072 						tt_num_vlan)) {
4073 request_table:
4074 			batadv_dbg(BATADV_DBG_TT, bat_priv,
4075 				   "TT inconsistency for %pM. Need to retrieve the correct information (ttvn: %u last_ttvn: %u num_changes: %u)\n",
4076 				   orig_node->orig, ttvn, orig_ttvn,
4077 				   tt_num_changes);
4078 			batadv_send_tt_request(bat_priv, orig_node, ttvn,
4079 					       tt_vlan, tt_num_vlan,
4080 					       full_table);
4081 			return;
4082 		}
4083 	}
4084 }
4085 
4086 /**
4087  * batadv_tt_global_client_is_roaming() - check if a client is marked as roaming
4088  * @bat_priv: the bat priv with all the soft interface information
4089  * @addr: the mac address of the client to check
4090  * @vid: VLAN identifier
4091  *
4092  * Return: true if we know that the client has moved from its old originator
4093  * to another one. This entry is still kept for consistency purposes and will be
4094  * deleted later by a DEL or because of timeout
4095  */
4096 bool batadv_tt_global_client_is_roaming(struct batadv_priv *bat_priv,
4097 					u8 *addr, unsigned short vid)
4098 {
4099 	struct batadv_tt_global_entry *tt_global_entry;
4100 	bool ret = false;
4101 
4102 	tt_global_entry = batadv_tt_global_hash_find(bat_priv, addr, vid);
4103 	if (!tt_global_entry)
4104 		goto out;
4105 
4106 	ret = tt_global_entry->common.flags & BATADV_TT_CLIENT_ROAM;
4107 	batadv_tt_global_entry_put(tt_global_entry);
4108 out:
4109 	return ret;
4110 }
4111 
4112 /**
4113  * batadv_tt_local_client_is_roaming() - tells whether the client is roaming
4114  * @bat_priv: the bat priv with all the soft interface information
4115  * @addr: the mac address of the local client to query
4116  * @vid: VLAN identifier
4117  *
4118  * Return: true if the local client is known to be roaming (it is not served by
4119  * this node anymore) or not. If yes, the client is still present in the table
4120  * to keep the latter consistent with the node TTVN
4121  */
4122 bool batadv_tt_local_client_is_roaming(struct batadv_priv *bat_priv,
4123 				       u8 *addr, unsigned short vid)
4124 {
4125 	struct batadv_tt_local_entry *tt_local_entry;
4126 	bool ret = false;
4127 
4128 	tt_local_entry = batadv_tt_local_hash_find(bat_priv, addr, vid);
4129 	if (!tt_local_entry)
4130 		goto out;
4131 
4132 	ret = tt_local_entry->common.flags & BATADV_TT_CLIENT_ROAM;
4133 	batadv_tt_local_entry_put(tt_local_entry);
4134 out:
4135 	return ret;
4136 }
4137 
4138 /**
4139  * batadv_tt_add_temporary_global_entry() - Add temporary entry to global TT
4140  * @bat_priv: the bat priv with all the soft interface information
4141  * @orig_node: orig node which the temporary entry should be associated with
4142  * @addr: mac address of the client
4143  * @vid: VLAN id of the new temporary global translation table
4144  *
4145  * Return: true when temporary tt entry could be added, false otherwise
4146  */
4147 bool batadv_tt_add_temporary_global_entry(struct batadv_priv *bat_priv,
4148 					  struct batadv_orig_node *orig_node,
4149 					  const unsigned char *addr,
4150 					  unsigned short vid)
4151 {
4152 	/* ignore loop detect macs, they are not supposed to be in the tt local
4153 	 * data as well.
4154 	 */
4155 	if (batadv_bla_is_loopdetect_mac(addr))
4156 		return false;
4157 
4158 	if (!batadv_tt_global_add(bat_priv, orig_node, addr, vid,
4159 				  BATADV_TT_CLIENT_TEMP,
4160 				  atomic_read(&orig_node->last_ttvn)))
4161 		return false;
4162 
4163 	batadv_dbg(BATADV_DBG_TT, bat_priv,
4164 		   "Added temporary global client (addr: %pM, vid: %d, orig: %pM)\n",
4165 		   addr, batadv_print_vid(vid), orig_node->orig);
4166 
4167 	return true;
4168 }
4169 
4170 /**
4171  * batadv_tt_local_resize_to_mtu() - resize the local translation table fit the
4172  *  maximum packet size that can be transported through the mesh
4173  * @soft_iface: netdev struct of the mesh interface
4174  *
4175  * Remove entries older than 'timeout' and half timeout if more entries need
4176  * to be removed.
4177  */
4178 void batadv_tt_local_resize_to_mtu(struct net_device *soft_iface)
4179 {
4180 	struct batadv_priv *bat_priv = netdev_priv(soft_iface);
4181 	int packet_size_max = atomic_read(&bat_priv->packet_size_max);
4182 	int table_size, timeout = BATADV_TT_LOCAL_TIMEOUT / 2;
4183 	bool reduced = false;
4184 
4185 	spin_lock_bh(&bat_priv->tt.commit_lock);
4186 
4187 	while (true) {
4188 		table_size = batadv_tt_local_table_transmit_size(bat_priv);
4189 		if (packet_size_max >= table_size)
4190 			break;
4191 
4192 		batadv_tt_local_purge(bat_priv, timeout);
4193 		batadv_tt_local_purge_pending_clients(bat_priv);
4194 
4195 		timeout /= 2;
4196 		reduced = true;
4197 		net_ratelimited_function(batadv_info, soft_iface,
4198 					 "Forced to purge local tt entries to fit new maximum fragment MTU (%i)\n",
4199 					 packet_size_max);
4200 	}
4201 
4202 	/* commit these changes immediately, to avoid synchronization problem
4203 	 * with the TTVN
4204 	 */
4205 	if (reduced)
4206 		batadv_tt_local_commit_changes_nolock(bat_priv);
4207 
4208 	spin_unlock_bh(&bat_priv->tt.commit_lock);
4209 }
4210 
4211 /**
4212  * batadv_tt_tvlv_ogm_handler_v1() - process incoming tt tvlv container
4213  * @bat_priv: the bat priv with all the soft interface information
4214  * @orig: the orig_node of the ogm
4215  * @flags: flags indicating the tvlv state (see batadv_tvlv_handler_flags)
4216  * @tvlv_value: tvlv buffer containing the gateway data
4217  * @tvlv_value_len: tvlv buffer length
4218  */
4219 static void batadv_tt_tvlv_ogm_handler_v1(struct batadv_priv *bat_priv,
4220 					  struct batadv_orig_node *orig,
4221 					  u8 flags, void *tvlv_value,
4222 					  u16 tvlv_value_len)
4223 {
4224 	struct batadv_tvlv_tt_vlan_data *tt_vlan;
4225 	struct batadv_tvlv_tt_change *tt_change;
4226 	struct batadv_tvlv_tt_data *tt_data;
4227 	u16 num_entries, num_vlan;
4228 
4229 	if (tvlv_value_len < sizeof(*tt_data))
4230 		return;
4231 
4232 	tt_data = (struct batadv_tvlv_tt_data *)tvlv_value;
4233 	tvlv_value_len -= sizeof(*tt_data);
4234 
4235 	num_vlan = ntohs(tt_data->num_vlan);
4236 
4237 	if (tvlv_value_len < sizeof(*tt_vlan) * num_vlan)
4238 		return;
4239 
4240 	tt_vlan = (struct batadv_tvlv_tt_vlan_data *)(tt_data + 1);
4241 	tt_change = (struct batadv_tvlv_tt_change *)(tt_vlan + num_vlan);
4242 	tvlv_value_len -= sizeof(*tt_vlan) * num_vlan;
4243 
4244 	num_entries = batadv_tt_entries(tvlv_value_len);
4245 
4246 	batadv_tt_update_orig(bat_priv, orig, tt_vlan, num_vlan, tt_change,
4247 			      num_entries, tt_data->ttvn);
4248 }
4249 
4250 /**
4251  * batadv_tt_tvlv_unicast_handler_v1() - process incoming (unicast) tt tvlv
4252  *  container
4253  * @bat_priv: the bat priv with all the soft interface information
4254  * @src: mac address of tt tvlv sender
4255  * @dst: mac address of tt tvlv recipient
4256  * @tvlv_value: tvlv buffer containing the tt data
4257  * @tvlv_value_len: tvlv buffer length
4258  *
4259  * Return: NET_RX_DROP if the tt tvlv is to be re-routed, NET_RX_SUCCESS
4260  * otherwise.
4261  */
4262 static int batadv_tt_tvlv_unicast_handler_v1(struct batadv_priv *bat_priv,
4263 					     u8 *src, u8 *dst,
4264 					     void *tvlv_value,
4265 					     u16 tvlv_value_len)
4266 {
4267 	struct batadv_tvlv_tt_data *tt_data;
4268 	u16 tt_vlan_len, tt_num_entries;
4269 	char tt_flag;
4270 	bool ret;
4271 
4272 	if (tvlv_value_len < sizeof(*tt_data))
4273 		return NET_RX_SUCCESS;
4274 
4275 	tt_data = (struct batadv_tvlv_tt_data *)tvlv_value;
4276 	tvlv_value_len -= sizeof(*tt_data);
4277 
4278 	tt_vlan_len = sizeof(struct batadv_tvlv_tt_vlan_data);
4279 	tt_vlan_len *= ntohs(tt_data->num_vlan);
4280 
4281 	if (tvlv_value_len < tt_vlan_len)
4282 		return NET_RX_SUCCESS;
4283 
4284 	tvlv_value_len -= tt_vlan_len;
4285 	tt_num_entries = batadv_tt_entries(tvlv_value_len);
4286 
4287 	switch (tt_data->flags & BATADV_TT_DATA_TYPE_MASK) {
4288 	case BATADV_TT_REQUEST:
4289 		batadv_inc_counter(bat_priv, BATADV_CNT_TT_REQUEST_RX);
4290 
4291 		/* If this node cannot provide a TT response the tt_request is
4292 		 * forwarded
4293 		 */
4294 		ret = batadv_send_tt_response(bat_priv, tt_data, src, dst);
4295 		if (!ret) {
4296 			if (tt_data->flags & BATADV_TT_FULL_TABLE)
4297 				tt_flag = 'F';
4298 			else
4299 				tt_flag = '.';
4300 
4301 			batadv_dbg(BATADV_DBG_TT, bat_priv,
4302 				   "Routing TT_REQUEST to %pM [%c]\n",
4303 				   dst, tt_flag);
4304 			/* tvlv API will re-route the packet */
4305 			return NET_RX_DROP;
4306 		}
4307 		break;
4308 	case BATADV_TT_RESPONSE:
4309 		batadv_inc_counter(bat_priv, BATADV_CNT_TT_RESPONSE_RX);
4310 
4311 		if (batadv_is_my_mac(bat_priv, dst)) {
4312 			batadv_handle_tt_response(bat_priv, tt_data,
4313 						  src, tt_num_entries);
4314 			return NET_RX_SUCCESS;
4315 		}
4316 
4317 		if (tt_data->flags & BATADV_TT_FULL_TABLE)
4318 			tt_flag =  'F';
4319 		else
4320 			tt_flag = '.';
4321 
4322 		batadv_dbg(BATADV_DBG_TT, bat_priv,
4323 			   "Routing TT_RESPONSE to %pM [%c]\n", dst, tt_flag);
4324 
4325 		/* tvlv API will re-route the packet */
4326 		return NET_RX_DROP;
4327 	}
4328 
4329 	return NET_RX_SUCCESS;
4330 }
4331 
4332 /**
4333  * batadv_roam_tvlv_unicast_handler_v1() - process incoming tt roam tvlv
4334  *  container
4335  * @bat_priv: the bat priv with all the soft interface information
4336  * @src: mac address of tt tvlv sender
4337  * @dst: mac address of tt tvlv recipient
4338  * @tvlv_value: tvlv buffer containing the tt data
4339  * @tvlv_value_len: tvlv buffer length
4340  *
4341  * Return: NET_RX_DROP if the tt roam tvlv is to be re-routed, NET_RX_SUCCESS
4342  * otherwise.
4343  */
4344 static int batadv_roam_tvlv_unicast_handler_v1(struct batadv_priv *bat_priv,
4345 					       u8 *src, u8 *dst,
4346 					       void *tvlv_value,
4347 					       u16 tvlv_value_len)
4348 {
4349 	struct batadv_tvlv_roam_adv *roaming_adv;
4350 	struct batadv_orig_node *orig_node = NULL;
4351 
4352 	/* If this node is not the intended recipient of the
4353 	 * roaming advertisement the packet is forwarded
4354 	 * (the tvlv API will re-route the packet).
4355 	 */
4356 	if (!batadv_is_my_mac(bat_priv, dst))
4357 		return NET_RX_DROP;
4358 
4359 	if (tvlv_value_len < sizeof(*roaming_adv))
4360 		goto out;
4361 
4362 	orig_node = batadv_orig_hash_find(bat_priv, src);
4363 	if (!orig_node)
4364 		goto out;
4365 
4366 	batadv_inc_counter(bat_priv, BATADV_CNT_TT_ROAM_ADV_RX);
4367 	roaming_adv = (struct batadv_tvlv_roam_adv *)tvlv_value;
4368 
4369 	batadv_dbg(BATADV_DBG_TT, bat_priv,
4370 		   "Received ROAMING_ADV from %pM (client %pM)\n",
4371 		   src, roaming_adv->client);
4372 
4373 	batadv_tt_global_add(bat_priv, orig_node, roaming_adv->client,
4374 			     ntohs(roaming_adv->vid), BATADV_TT_CLIENT_ROAM,
4375 			     atomic_read(&orig_node->last_ttvn) + 1);
4376 
4377 out:
4378 	if (orig_node)
4379 		batadv_orig_node_put(orig_node);
4380 	return NET_RX_SUCCESS;
4381 }
4382 
4383 /**
4384  * batadv_tt_init() - initialise the translation table internals
4385  * @bat_priv: the bat priv with all the soft interface information
4386  *
4387  * Return: 0 on success or negative error number in case of failure.
4388  */
4389 int batadv_tt_init(struct batadv_priv *bat_priv)
4390 {
4391 	int ret;
4392 
4393 	/* synchronized flags must be remote */
4394 	BUILD_BUG_ON(!(BATADV_TT_SYNC_MASK & BATADV_TT_REMOTE_MASK));
4395 
4396 	ret = batadv_tt_local_init(bat_priv);
4397 	if (ret < 0)
4398 		return ret;
4399 
4400 	ret = batadv_tt_global_init(bat_priv);
4401 	if (ret < 0)
4402 		return ret;
4403 
4404 	batadv_tvlv_handler_register(bat_priv, batadv_tt_tvlv_ogm_handler_v1,
4405 				     batadv_tt_tvlv_unicast_handler_v1,
4406 				     BATADV_TVLV_TT, 1, BATADV_NO_FLAGS);
4407 
4408 	batadv_tvlv_handler_register(bat_priv, NULL,
4409 				     batadv_roam_tvlv_unicast_handler_v1,
4410 				     BATADV_TVLV_ROAM, 1, BATADV_NO_FLAGS);
4411 
4412 	INIT_DELAYED_WORK(&bat_priv->tt.work, batadv_tt_purge);
4413 	queue_delayed_work(batadv_event_workqueue, &bat_priv->tt.work,
4414 			   msecs_to_jiffies(BATADV_TT_WORK_PERIOD));
4415 
4416 	return 1;
4417 }
4418 
4419 /**
4420  * batadv_tt_global_is_isolated() - check if a client is marked as isolated
4421  * @bat_priv: the bat priv with all the soft interface information
4422  * @addr: the mac address of the client
4423  * @vid: the identifier of the VLAN where this client is connected
4424  *
4425  * Return: true if the client is marked with the TT_CLIENT_ISOLA flag, false
4426  * otherwise
4427  */
4428 bool batadv_tt_global_is_isolated(struct batadv_priv *bat_priv,
4429 				  const u8 *addr, unsigned short vid)
4430 {
4431 	struct batadv_tt_global_entry *tt;
4432 	bool ret;
4433 
4434 	tt = batadv_tt_global_hash_find(bat_priv, addr, vid);
4435 	if (!tt)
4436 		return false;
4437 
4438 	ret = tt->common.flags & BATADV_TT_CLIENT_ISOLA;
4439 
4440 	batadv_tt_global_entry_put(tt);
4441 
4442 	return ret;
4443 }
4444 
4445 /**
4446  * batadv_tt_cache_init() - Initialize tt memory object cache
4447  *
4448  * Return: 0 on success or negative error number in case of failure.
4449  */
4450 int __init batadv_tt_cache_init(void)
4451 {
4452 	size_t tl_size = sizeof(struct batadv_tt_local_entry);
4453 	size_t tg_size = sizeof(struct batadv_tt_global_entry);
4454 	size_t tt_orig_size = sizeof(struct batadv_tt_orig_list_entry);
4455 	size_t tt_change_size = sizeof(struct batadv_tt_change_node);
4456 	size_t tt_req_size = sizeof(struct batadv_tt_req_node);
4457 	size_t tt_roam_size = sizeof(struct batadv_tt_roam_node);
4458 
4459 	batadv_tl_cache = kmem_cache_create("batadv_tl_cache", tl_size, 0,
4460 					    SLAB_HWCACHE_ALIGN, NULL);
4461 	if (!batadv_tl_cache)
4462 		return -ENOMEM;
4463 
4464 	batadv_tg_cache = kmem_cache_create("batadv_tg_cache", tg_size, 0,
4465 					    SLAB_HWCACHE_ALIGN, NULL);
4466 	if (!batadv_tg_cache)
4467 		goto err_tt_tl_destroy;
4468 
4469 	batadv_tt_orig_cache = kmem_cache_create("batadv_tt_orig_cache",
4470 						 tt_orig_size, 0,
4471 						 SLAB_HWCACHE_ALIGN, NULL);
4472 	if (!batadv_tt_orig_cache)
4473 		goto err_tt_tg_destroy;
4474 
4475 	batadv_tt_change_cache = kmem_cache_create("batadv_tt_change_cache",
4476 						   tt_change_size, 0,
4477 						   SLAB_HWCACHE_ALIGN, NULL);
4478 	if (!batadv_tt_change_cache)
4479 		goto err_tt_orig_destroy;
4480 
4481 	batadv_tt_req_cache = kmem_cache_create("batadv_tt_req_cache",
4482 						tt_req_size, 0,
4483 						SLAB_HWCACHE_ALIGN, NULL);
4484 	if (!batadv_tt_req_cache)
4485 		goto err_tt_change_destroy;
4486 
4487 	batadv_tt_roam_cache = kmem_cache_create("batadv_tt_roam_cache",
4488 						 tt_roam_size, 0,
4489 						 SLAB_HWCACHE_ALIGN, NULL);
4490 	if (!batadv_tt_roam_cache)
4491 		goto err_tt_req_destroy;
4492 
4493 	return 0;
4494 
4495 err_tt_req_destroy:
4496 	kmem_cache_destroy(batadv_tt_req_cache);
4497 	batadv_tt_req_cache = NULL;
4498 err_tt_change_destroy:
4499 	kmem_cache_destroy(batadv_tt_change_cache);
4500 	batadv_tt_change_cache = NULL;
4501 err_tt_orig_destroy:
4502 	kmem_cache_destroy(batadv_tt_orig_cache);
4503 	batadv_tt_orig_cache = NULL;
4504 err_tt_tg_destroy:
4505 	kmem_cache_destroy(batadv_tg_cache);
4506 	batadv_tg_cache = NULL;
4507 err_tt_tl_destroy:
4508 	kmem_cache_destroy(batadv_tl_cache);
4509 	batadv_tl_cache = NULL;
4510 
4511 	return -ENOMEM;
4512 }
4513 
4514 /**
4515  * batadv_tt_cache_destroy() - Destroy tt memory object cache
4516  */
4517 void batadv_tt_cache_destroy(void)
4518 {
4519 	kmem_cache_destroy(batadv_tl_cache);
4520 	kmem_cache_destroy(batadv_tg_cache);
4521 	kmem_cache_destroy(batadv_tt_orig_cache);
4522 	kmem_cache_destroy(batadv_tt_change_cache);
4523 	kmem_cache_destroy(batadv_tt_req_cache);
4524 	kmem_cache_destroy(batadv_tt_roam_cache);
4525 }
4526