translation-table.c

   1// SPDX-License-Identifier: GPL-2.0
   2/* Copyright (C) B.A.T.M.A.N. contributors:
   3 *
   4 * Marek Lindner, Simon Wunderlich, Antonio Quartulli
   5 */
   6
   7#include "translation-table.h"
   8#include "main.h"
   9
  10#include <linux/atomic.h>
  11#include <linux/bitops.h>
  12#include <linux/build_bug.h>
  13#include <linux/byteorder/generic.h>
  14#include <linux/cache.h>
  15#include <linux/compiler.h>
  16#include <linux/container_of.h>
  17#include <linux/crc32.h>
  18#include <linux/err.h>
  19#include <linux/errno.h>
  20#include <linux/etherdevice.h>
  21#include <linux/gfp.h>
  22#include <linux/if_ether.h>
  23#include <linux/init.h>
  24#include <linux/jhash.h>
  25#include <linux/jiffies.h>
  26#include <linux/kref.h>
  27#include <linux/list.h>
  28#include <linux/lockdep.h>
  29#include <linux/net.h>
  30#include <linux/netdevice.h>
  31#include <linux/netlink.h>
  32#include <linux/overflow.h>
  33#include <linux/rculist.h>
  34#include <linux/rcupdate.h>
  35#include <linux/skbuff.h>
  36#include <linux/slab.h>
  37#include <linux/spinlock.h>
  38#include <linux/stddef.h>
  39#include <linux/string.h>
  40#include <linux/workqueue.h>
  41#include <net/genetlink.h>
  42#include <net/netlink.h>
  43#include <uapi/linux/batadv_packet.h>
  44#include <uapi/linux/batman_adv.h>
  45
  46#include "bridge_loop_avoidance.h"
  47#include "hard-interface.h"
  48#include "hash.h"
  49#include "log.h"
  50#include "mesh-interface.h"
  51#include "netlink.h"
  52#include "originator.h"
  53#include "tvlv.h"
  54
  55static struct kmem_cache *batadv_tl_cache __read_mostly;
  56static struct kmem_cache *batadv_tg_cache __read_mostly;
  57static struct kmem_cache *batadv_tt_orig_cache __read_mostly;
  58static struct kmem_cache *batadv_tt_change_cache __read_mostly;
  59static struct kmem_cache *batadv_tt_req_cache __read_mostly;
  60static struct kmem_cache *batadv_tt_roam_cache __read_mostly;
  61
  62/* hash class keys */
  63static struct lock_class_key batadv_tt_local_hash_lock_class_key;
  64static struct lock_class_key batadv_tt_global_hash_lock_class_key;
  65
  66static void batadv_send_roam_adv(struct batadv_priv *bat_priv, u8 *client,
  67				 unsigned short vid,
  68				 struct batadv_orig_node *orig_node);
  69static void batadv_tt_purge(struct work_struct *work);
  70static void
  71batadv_tt_global_del_orig_list(struct batadv_tt_global_entry *tt_global_entry);
  72static void batadv_tt_global_del(struct batadv_priv *bat_priv,
  73				 struct batadv_orig_node *orig_node,
  74				 const unsigned char *addr,
  75				 unsigned short vid, const char *message,
  76				 bool roaming);
  77
  78/**
  79 * batadv_compare_tt() - check if two TT entries are the same
  80 * @node: the list element pointer of the first TT entry
  81 * @data2: pointer to the tt_common_entry of the second TT entry
  82 *
  83 * Compare the MAC address and the VLAN ID of the two TT entries and check if
  84 * they are the same TT client.
  85 * Return: true if the two TT clients are the same, false otherwise
  86 */
  87static bool batadv_compare_tt(const struct hlist_node *node, const void *data2)
  88{
  89	const void *data1 = container_of(node, struct batadv_tt_common_entry,
  90					 hash_entry);
  91	const struct batadv_tt_common_entry *tt1 = data1;
  92	const struct batadv_tt_common_entry *tt2 = data2;
  93
  94	return (tt1->vid == tt2->vid) && batadv_compare_eth(data1, data2);
  95}
  96
  97/**
  98 * batadv_choose_tt() - return the index of the tt entry in the hash table
  99 * @data: pointer to the tt_common_entry object to map
 100 * @size: the size of the hash table
 101 *
 102 * Return: the hash index where the object represented by 'data' should be
 103 * stored at.
 104 */
 105static inline u32 batadv_choose_tt(const void *data, u32 size)
 106{
 107	const struct batadv_tt_common_entry *tt;
 108	u32 hash = 0;
 109
 110	tt = data;
 111	hash = jhash(&tt->addr, ETH_ALEN, hash);
 112	hash = jhash(&tt->vid, sizeof(tt->vid), hash);
 113
 114	return hash % size;
 115}
 116
 117/**
 118 * batadv_tt_hash_find() - look for a client in the given hash table
 119 * @hash: the hash table to search
 120 * @addr: the mac address of the client to look for
 121 * @vid: VLAN identifier
 122 *
 123 * Return: a pointer to the tt_common struct belonging to the searched client if
 124 * found, NULL otherwise.
 125 */
 126static struct batadv_tt_common_entry *
 127batadv_tt_hash_find(struct batadv_hashtable *hash, const u8 *addr,
 128		    unsigned short vid)
 129{
 130	struct hlist_head *head;
 131	struct batadv_tt_common_entry to_search, *tt, *tt_tmp = NULL;
 132	u32 index;
 133
 134	if (!hash)
 135		return NULL;
 136
 137	ether_addr_copy(to_search.addr, addr);
 138	to_search.vid = vid;
 139
 140	index = batadv_choose_tt(&to_search, hash->size);
 141	head = &hash->table[index];
 142
 143	rcu_read_lock();
 144	hlist_for_each_entry_rcu(tt, head, hash_entry) {
 145		if (!batadv_compare_eth(tt, addr))
 146			continue;
 147
 148		if (tt->vid != vid)
 149			continue;
 150
 151		if (!kref_get_unless_zero(&tt->refcount))
 152			continue;
 153
 154		tt_tmp = tt;
 155		break;
 156	}
 157	rcu_read_unlock();
 158
 159	return tt_tmp;
 160}
 161
 162/**
 163 * batadv_tt_local_hash_find() - search the local table for a given client
 164 * @bat_priv: the bat priv with all the mesh interface information
 165 * @addr: the mac address of the client to look for
 166 * @vid: VLAN identifier
 167 *
 168 * Return: a pointer to the corresponding tt_local_entry struct if the client is
 169 * found, NULL otherwise.
 170 */
 171static struct batadv_tt_local_entry *
 172batadv_tt_local_hash_find(struct batadv_priv *bat_priv, const u8 *addr,
 173			  unsigned short vid)
 174{
 175	struct batadv_tt_common_entry *tt_common_entry;
 176	struct batadv_tt_local_entry *tt_local_entry = NULL;
 177
 178	tt_common_entry = batadv_tt_hash_find(bat_priv->tt.local_hash, addr,
 179					      vid);
 180	if (tt_common_entry)
 181		tt_local_entry = container_of(tt_common_entry,
 182					      struct batadv_tt_local_entry,
 183					      common);
 184	return tt_local_entry;
 185}
 186
 187/**
 188 * batadv_tt_global_hash_find() - search the global table for a given client
 189 * @bat_priv: the bat priv with all the mesh interface information
 190 * @addr: the mac address of the client to look for
 191 * @vid: VLAN identifier
 192 *
 193 * Return: a pointer to the corresponding tt_global_entry struct if the client
 194 * is found, NULL otherwise.
 195 */
 196struct batadv_tt_global_entry *
 197batadv_tt_global_hash_find(struct batadv_priv *bat_priv, const u8 *addr,
 198			   unsigned short vid)
 199{
 200	struct batadv_tt_common_entry *tt_common_entry;
 201	struct batadv_tt_global_entry *tt_global_entry = NULL;
 202
 203	tt_common_entry = batadv_tt_hash_find(bat_priv->tt.global_hash, addr,
 204					      vid);
 205	if (tt_common_entry)
 206		tt_global_entry = container_of(tt_common_entry,
 207					       struct batadv_tt_global_entry,
 208					       common);
 209	return tt_global_entry;
 210}
 211
 212/**
 213 * batadv_tt_local_entry_release() - release tt_local_entry from lists and queue
 214 *  for free after rcu grace period
 215 * @ref: kref pointer of the batadv_tt_local_entry
 216 */
 217static void batadv_tt_local_entry_release(struct kref *ref)
 218{
 219	struct batadv_tt_local_entry *tt_local_entry;
 220
 221	tt_local_entry = container_of(ref, struct batadv_tt_local_entry,
 222				      common.refcount);
 223
 224	batadv_meshif_vlan_put(tt_local_entry->vlan);
 225
 226	kfree_rcu(tt_local_entry, common.rcu);
 227}
 228
 229/**
 230 * batadv_tt_local_entry_put() - decrement the tt_local_entry refcounter and
 231 *  possibly release it
 232 * @tt_local_entry: tt_local_entry to be free'd
 233 */
 234static void
 235batadv_tt_local_entry_put(struct batadv_tt_local_entry *tt_local_entry)
 236{
 237	if (!tt_local_entry)
 238		return;
 239
 240	kref_put(&tt_local_entry->common.refcount,
 241		 batadv_tt_local_entry_release);
 242}
 243
 244/**
 245 * batadv_tt_global_entry_release() - release tt_global_entry from lists and
 246 *  queue for free after rcu grace period
 247 * @ref: kref pointer of the batadv_tt_global_entry
 248 */
 249void batadv_tt_global_entry_release(struct kref *ref)
 250{
 251	struct batadv_tt_global_entry *tt_global_entry;
 252
 253	tt_global_entry = container_of(ref, struct batadv_tt_global_entry,
 254				       common.refcount);
 255
 256	batadv_tt_global_del_orig_list(tt_global_entry);
 257
 258	kfree_rcu(tt_global_entry, common.rcu);
 259}
 260
 261/**
 262 * batadv_tt_global_hash_count() - count the number of orig entries
 263 * @bat_priv: the bat priv with all the mesh interface information
 264 * @addr: the mac address of the client to count entries for
 265 * @vid: VLAN identifier
 266 *
 267 * Return: the number of originators advertising the given address/data
 268 * (excluding our self).
 269 */
 270int batadv_tt_global_hash_count(struct batadv_priv *bat_priv,
 271				const u8 *addr, unsigned short vid)
 272{
 273	struct batadv_tt_global_entry *tt_global_entry;
 274	int count;
 275
 276	tt_global_entry = batadv_tt_global_hash_find(bat_priv, addr, vid);
 277	if (!tt_global_entry)
 278		return 0;
 279
 280	count = atomic_read(&tt_global_entry->orig_list_count);
 281	batadv_tt_global_entry_put(tt_global_entry);
 282
 283	return count;
 284}
 285
 286/**
 287 * batadv_tt_local_size_mod() - change the size by v of the local table
 288 *  identified by vid
 289 * @bat_priv: the bat priv with all the mesh interface information
 290 * @vid: the VLAN identifier of the sub-table to change
 291 * @v: the amount to sum to the local table size
 292 */
 293static void batadv_tt_local_size_mod(struct batadv_priv *bat_priv,
 294				     unsigned short vid, int v)
 295{
 296	struct batadv_meshif_vlan *vlan;
 297
 298	vlan = batadv_meshif_vlan_get(bat_priv, vid);
 299	if (!vlan)
 300		return;
 301
 302	atomic_add(v, &vlan->tt.num_entries);
 303
 304	batadv_meshif_vlan_put(vlan);
 305}
 306
 307/**
 308 * batadv_tt_local_size_inc() - increase by one the local table size for the
 309 *  given vid
 310 * @bat_priv: the bat priv with all the mesh interface information
 311 * @vid: the VLAN identifier
 312 */
 313static void batadv_tt_local_size_inc(struct batadv_priv *bat_priv,
 314				     unsigned short vid)
 315{
 316	batadv_tt_local_size_mod(bat_priv, vid, 1);
 317}
 318
 319/**
 320 * batadv_tt_local_size_dec() - decrease by one the local table size for the
 321 *  given vid
 322 * @bat_priv: the bat priv with all the mesh interface information
 323 * @vid: the VLAN identifier
 324 */
 325static void batadv_tt_local_size_dec(struct batadv_priv *bat_priv,
 326				     unsigned short vid)
 327{
 328	batadv_tt_local_size_mod(bat_priv, vid, -1);
 329}
 330
 331/**
 332 * batadv_tt_global_size_mod() - change the size by v of the global table
 333 *  for orig_node identified by vid
 334 * @orig_node: the originator for which the table has to be modified
 335 * @vid: the VLAN identifier
 336 * @v: the amount to sum to the global table size
 337 */
 338static void batadv_tt_global_size_mod(struct batadv_orig_node *orig_node,
 339				      unsigned short vid, int v)
 340{
 341	struct batadv_orig_node_vlan *vlan;
 342
 343	vlan = batadv_orig_node_vlan_new(orig_node, vid);
 344	if (!vlan)
 345		return;
 346
 347	if (atomic_add_return(v, &vlan->tt.num_entries) == 0) {
 348		spin_lock_bh(&orig_node->vlan_list_lock);
 349		if (!hlist_unhashed(&vlan->list)) {
 350			hlist_del_init_rcu(&vlan->list);
 351			batadv_orig_node_vlan_put(vlan);
 352		}
 353		spin_unlock_bh(&orig_node->vlan_list_lock);
 354	}
 355
 356	batadv_orig_node_vlan_put(vlan);
 357}
 358
 359/**
 360 * batadv_tt_global_size_inc() - increase by one the global table size for the
 361 *  given vid
 362 * @orig_node: the originator which global table size has to be decreased
 363 * @vid: the vlan identifier
 364 */
 365static void batadv_tt_global_size_inc(struct batadv_orig_node *orig_node,
 366				      unsigned short vid)
 367{
 368	batadv_tt_global_size_mod(orig_node, vid, 1);
 369}
 370
 371/**
 372 * batadv_tt_global_size_dec() - decrease by one the global table size for the
 373 *  given vid
 374 * @orig_node: the originator which global table size has to be decreased
 375 * @vid: the vlan identifier
 376 */
 377static void batadv_tt_global_size_dec(struct batadv_orig_node *orig_node,
 378				      unsigned short vid)
 379{
 380	batadv_tt_global_size_mod(orig_node, vid, -1);
 381}
 382
 383/**
 384 * batadv_tt_orig_list_entry_release() - release tt orig entry from lists and
 385 *  queue for free after rcu grace period
 386 * @ref: kref pointer of the tt orig entry
 387 */
 388static void batadv_tt_orig_list_entry_release(struct kref *ref)
 389{
 390	struct batadv_tt_orig_list_entry *orig_entry;
 391
 392	orig_entry = container_of(ref, struct batadv_tt_orig_list_entry,
 393				  refcount);
 394
 395	batadv_orig_node_put(orig_entry->orig_node);
 396	kfree_rcu(orig_entry, rcu);
 397}
 398
 399/**
 400 * batadv_tt_orig_list_entry_put() - decrement the tt orig entry refcounter and
 401 *  possibly release it
 402 * @orig_entry: tt orig entry to be free'd
 403 */
 404static void
 405batadv_tt_orig_list_entry_put(struct batadv_tt_orig_list_entry *orig_entry)
 406{
 407	if (!orig_entry)
 408		return;
 409
 410	kref_put(&orig_entry->refcount, batadv_tt_orig_list_entry_release);
 411}
 412
 413/**
 414 * batadv_tt_local_event() - store a local TT event (ADD/DEL)
 415 * @bat_priv: the bat priv with all the mesh interface information
 416 * @tt_local_entry: the TT entry involved in the event
 417 * @event_flags: flags to store in the event structure
 418 */
 419static void batadv_tt_local_event(struct batadv_priv *bat_priv,
 420				  struct batadv_tt_local_entry *tt_local_entry,
 421				  u8 event_flags)
 422{
 423	struct batadv_tt_change_node *tt_change_node, *entry, *safe;
 424	struct batadv_tt_common_entry *common = &tt_local_entry->common;
 425	u8 flags = common->flags | event_flags;
 426	bool del_op_requested, del_op_entry;
 427	size_t changes;
 428
 429	tt_change_node = kmem_cache_alloc(batadv_tt_change_cache, GFP_ATOMIC);
 430	if (!tt_change_node)
 431		return;
 432
 433	tt_change_node->change.flags = flags;
 434	memset(tt_change_node->change.reserved, 0,
 435	       sizeof(tt_change_node->change.reserved));
 436	ether_addr_copy(tt_change_node->change.addr, common->addr);
 437	tt_change_node->change.vid = htons(common->vid);
 438
 439	del_op_requested = flags & BATADV_TT_CLIENT_DEL;
 440
 441	/* check for ADD+DEL, DEL+ADD, ADD+ADD or DEL+DEL events */
 442	spin_lock_bh(&bat_priv->tt.changes_list_lock);
 443	changes = READ_ONCE(bat_priv->tt.local_changes);
 444	list_for_each_entry_safe(entry, safe, &bat_priv->tt.changes_list,
 445				 list) {
 446		if (!batadv_compare_eth(entry->change.addr, common->addr))
 447			continue;
 448
 449		del_op_entry = entry->change.flags & BATADV_TT_CLIENT_DEL;
 450		if (del_op_requested != del_op_entry) {
 451			/* DEL+ADD in the same orig interval have no effect and
 452			 * can be removed to avoid silly behaviour on the
 453			 * receiver side. The  other way around (ADD+DEL) can
 454			 * happen in case of roaming of  a client still in the
 455			 * NEW state. Roaming of NEW clients is now possible due
 456			 * to automatically recognition of "temporary" clients
 457			 */
 458			list_del(&entry->list);
 459			kmem_cache_free(batadv_tt_change_cache, entry);
 460			changes--;
 461		} else {
 462			/* this is a second add or del in the same originator
 463			 * interval. It could mean that flags have been changed
 464			 * (e.g. double add): update them
 465			 */
 466			entry->change.flags = flags;
 467		}
 468
 469		kmem_cache_free(batadv_tt_change_cache, tt_change_node);
 470		goto update_changes;
 471	}
 472
 473	/* track the change in the OGMinterval list */
 474	list_add_tail(&tt_change_node->list, &bat_priv->tt.changes_list);
 475	changes++;
 476
 477update_changes:
 478	WRITE_ONCE(bat_priv->tt.local_changes, changes);
 479	spin_unlock_bh(&bat_priv->tt.changes_list_lock);
 480}
 481
 482/**
 483 * batadv_tt_len() - compute length in bytes of given number of tt changes
 484 * @changes_num: number of tt changes
 485 *
 486 * Return: computed length in bytes.
 487 */
 488static int batadv_tt_len(int changes_num)
 489{
 490	return changes_num * sizeof(struct batadv_tvlv_tt_change);
 491}
 492
 493/**
 494 * batadv_tt_entries() - compute the number of entries fitting in tt_len bytes
 495 * @tt_len: available space
 496 *
 497 * Return: the number of entries.
 498 */
 499static u16 batadv_tt_entries(u16 tt_len)
 500{
 501	return tt_len / batadv_tt_len(1);
 502}
 503
 504/**
 505 * batadv_tt_local_table_transmit_size() - calculates the local translation
 506 *  table size when transmitted over the air
 507 * @bat_priv: the bat priv with all the mesh interface information
 508 *
 509 * Return: local translation table size in bytes.
 510 */
 511static int batadv_tt_local_table_transmit_size(struct batadv_priv *bat_priv)
 512{
 513	u16 num_vlan = 0;
 514	u16 tt_local_entries = 0;
 515	struct batadv_meshif_vlan *vlan;
 516	int hdr_size;
 517
 518	rcu_read_lock();
 519	hlist_for_each_entry_rcu(vlan, &bat_priv->meshif_vlan_list, list) {
 520		num_vlan++;
 521		tt_local_entries += atomic_read(&vlan->tt.num_entries);
 522	}
 523	rcu_read_unlock();
 524
 525	/* header size of tvlv encapsulated tt response payload */
 526	hdr_size = sizeof(struct batadv_unicast_tvlv_packet);
 527	hdr_size += sizeof(struct batadv_tvlv_hdr);
 528	hdr_size += sizeof(struct batadv_tvlv_tt_data);
 529	hdr_size += num_vlan * sizeof(struct batadv_tvlv_tt_vlan_data);
 530
 531	return hdr_size + batadv_tt_len(tt_local_entries);
 532}
 533
 534static int batadv_tt_local_init(struct batadv_priv *bat_priv)
 535{
 536	if (bat_priv->tt.local_hash)
 537		return 0;
 538
 539	bat_priv->tt.local_hash = batadv_hash_new(1024);
 540
 541	if (!bat_priv->tt.local_hash)
 542		return -ENOMEM;
 543
 544	batadv_hash_set_lock_class(bat_priv->tt.local_hash,
 545				   &batadv_tt_local_hash_lock_class_key);
 546
 547	return 0;
 548}
 549
 550static void batadv_tt_global_free(struct batadv_priv *bat_priv,
 551				  struct batadv_tt_global_entry *tt_global,
 552				  const char *message)
 553{
 554	struct batadv_tt_global_entry *tt_removed_entry;
 555	struct hlist_node *tt_removed_node;
 556
 557	batadv_dbg(BATADV_DBG_TT, bat_priv,
 558		   "Deleting global tt entry %pM (vid: %d): %s\n",
 559		   tt_global->common.addr,
 560		   batadv_print_vid(tt_global->common.vid), message);
 561
 562	tt_removed_node = batadv_hash_remove(bat_priv->tt.global_hash,
 563					     batadv_compare_tt,
 564					     batadv_choose_tt,
 565					     &tt_global->common);
 566	if (!tt_removed_node)
 567		return;
 568
 569	/* drop reference of remove hash entry */
 570	tt_removed_entry = hlist_entry(tt_removed_node,
 571				       struct batadv_tt_global_entry,
 572				       common.hash_entry);
 573	batadv_tt_global_entry_put(tt_removed_entry);
 574}
 575
 576/**
 577 * batadv_tt_local_add() - add a new client to the local table or update an
 578 *  existing client
 579 * @mesh_iface: netdev struct of the mesh interface
 580 * @addr: the mac address of the client to add
 581 * @vid: VLAN identifier
 582 * @ifindex: index of the interface where the client is connected to (useful to
 583 *  identify wireless clients)
 584 * @mark: the value contained in the skb->mark field of the received packet (if
 585 *  any)
 586 *
 587 * Return: true if the client was successfully added, false otherwise.
 588 */
 589bool batadv_tt_local_add(struct net_device *mesh_iface, const u8 *addr,
 590			 unsigned short vid, int ifindex, u32 mark)
 591{
 592	struct batadv_priv *bat_priv = netdev_priv(mesh_iface);
 593	struct batadv_tt_local_entry *tt_local;
 594	struct batadv_tt_global_entry *tt_global = NULL;
 595	struct net *net = dev_net(mesh_iface);
 596	struct batadv_meshif_vlan *vlan;
 597	struct net_device *in_dev = NULL;
 598	struct batadv_hard_iface *in_hardif = NULL;
 599	struct hlist_head *head;
 600	struct batadv_tt_orig_list_entry *orig_entry;
 601	int hash_added, table_size, packet_size_max;
 602	bool ret = false;
 603	bool roamed_back = false;
 604	u8 remote_flags;
 605	u32 match_mark;
 606
 607	if (ifindex != BATADV_NULL_IFINDEX)
 608		in_dev = dev_get_by_index(net, ifindex);
 609
 610	if (in_dev)
 611		in_hardif = batadv_hardif_get_by_netdev(in_dev);
 612
 613	tt_local = batadv_tt_local_hash_find(bat_priv, addr, vid);
 614
 615	if (!is_multicast_ether_addr(addr))
 616		tt_global = batadv_tt_global_hash_find(bat_priv, addr, vid);
 617
 618	if (tt_local) {
 619		tt_local->last_seen = jiffies;
 620		if (tt_local->common.flags & BATADV_TT_CLIENT_PENDING) {
 621			batadv_dbg(BATADV_DBG_TT, bat_priv,
 622				   "Re-adding pending client %pM (vid: %d)\n",
 623				   addr, batadv_print_vid(vid));
 624			/* whatever the reason why the PENDING flag was set,
 625			 * this is a client which was enqueued to be removed in
 626			 * this orig_interval. Since it popped up again, the
 627			 * flag can be reset like it was never enqueued
 628			 */
 629			tt_local->common.flags &= ~BATADV_TT_CLIENT_PENDING;
 630			goto add_event;
 631		}
 632
 633		if (tt_local->common.flags & BATADV_TT_CLIENT_ROAM) {
 634			batadv_dbg(BATADV_DBG_TT, bat_priv,
 635				   "Roaming client %pM (vid: %d) came back to its original location\n",
 636				   addr, batadv_print_vid(vid));
 637			/* the ROAM flag is set because this client roamed away
 638			 * and the node got a roaming_advertisement message. Now
 639			 * that the client popped up again at its original
 640			 * location such flag can be unset
 641			 */
 642			tt_local->common.flags &= ~BATADV_TT_CLIENT_ROAM;
 643			roamed_back = true;
 644		}
 645		goto check_roaming;
 646	}
 647
 648	/* Ignore the client if we cannot send it in a full table response. */
 649	table_size = batadv_tt_local_table_transmit_size(bat_priv);
 650	table_size += batadv_tt_len(1);
 651	packet_size_max = atomic_read(&bat_priv->packet_size_max);
 652	if (table_size > packet_size_max) {
 653		net_ratelimited_function(batadv_info, mesh_iface,
 654					 "Local translation table size (%i) exceeds maximum packet size (%i); Ignoring new local tt entry: %pM\n",
 655					 table_size, packet_size_max, addr);
 656		goto out;
 657	}
 658
 659	tt_local = kmem_cache_alloc(batadv_tl_cache, GFP_ATOMIC);
 660	if (!tt_local)
 661		goto out;
 662
 663	/* increase the refcounter of the related vlan */
 664	vlan = batadv_meshif_vlan_get(bat_priv, vid);
 665	if (!vlan) {
 666		net_ratelimited_function(batadv_info, mesh_iface,
 667					 "adding TT local entry %pM to non-existent VLAN %d\n",
 668					 addr, batadv_print_vid(vid));
 669		kmem_cache_free(batadv_tl_cache, tt_local);
 670		tt_local = NULL;
 671		goto out;
 672	}
 673
 674	batadv_dbg(BATADV_DBG_TT, bat_priv,
 675		   "Creating new local tt entry: %pM (vid: %d, ttvn: %d)\n",
 676		   addr, batadv_print_vid(vid),
 677		   (u8)atomic_read(&bat_priv->tt.vn));
 678
 679	ether_addr_copy(tt_local->common.addr, addr);
 680	/* The local entry has to be marked as NEW to avoid to send it in
 681	 * a full table response going out before the next ttvn increment
 682	 * (consistency check)
 683	 */
 684	tt_local->common.flags = BATADV_TT_CLIENT_NEW;
 685	tt_local->common.vid = vid;
 686	if (batadv_is_wifi_hardif(in_hardif))
 687		tt_local->common.flags |= BATADV_TT_CLIENT_WIFI;
 688	kref_init(&tt_local->common.refcount);
 689	tt_local->last_seen = jiffies;
 690	tt_local->common.added_at = tt_local->last_seen;
 691	tt_local->vlan = vlan;
 692
 693	/* the batman interface mac and multicast addresses should never be
 694	 * purged
 695	 */
 696	if (batadv_compare_eth(addr, mesh_iface->dev_addr) ||
 697	    is_multicast_ether_addr(addr))
 698		tt_local->common.flags |= BATADV_TT_CLIENT_NOPURGE;
 699
 700	kref_get(&tt_local->common.refcount);
 701	hash_added = batadv_hash_add(bat_priv->tt.local_hash, batadv_compare_tt,
 702				     batadv_choose_tt, &tt_local->common,
 703				     &tt_local->common.hash_entry);
 704
 705	if (unlikely(hash_added != 0)) {
 706		/* remove the reference for the hash */
 707		batadv_tt_local_entry_put(tt_local);
 708		goto out;
 709	}
 710
 711add_event:
 712	batadv_tt_local_event(bat_priv, tt_local, BATADV_NO_FLAGS);
 713
 714check_roaming:
 715	/* Check whether it is a roaming, but don't do anything if the roaming
 716	 * process has already been handled
 717	 */
 718	if (tt_global && !(tt_global->common.flags & BATADV_TT_CLIENT_ROAM)) {
 719		/* These node are probably going to update their tt table */
 720		head = &tt_global->orig_list;
 721		rcu_read_lock();
 722		hlist_for_each_entry_rcu(orig_entry, head, list) {
 723			batadv_send_roam_adv(bat_priv, tt_global->common.addr,
 724					     tt_global->common.vid,
 725					     orig_entry->orig_node);
 726		}
 727		rcu_read_unlock();
 728		if (roamed_back) {
 729			batadv_tt_global_free(bat_priv, tt_global,
 730					      "Roaming canceled");
 731		} else {
 732			/* The global entry has to be marked as ROAMING and
 733			 * has to be kept for consistency purpose
 734			 */
 735			tt_global->common.flags |= BATADV_TT_CLIENT_ROAM;
 736			tt_global->roam_at = jiffies;
 737		}
 738	}
 739
 740	/* store the current remote flags before altering them. This helps
 741	 * understanding is flags are changing or not
 742	 */
 743	remote_flags = tt_local->common.flags & BATADV_TT_REMOTE_MASK;
 744
 745	if (batadv_is_wifi_hardif(in_hardif))
 746		tt_local->common.flags |= BATADV_TT_CLIENT_WIFI;
 747	else
 748		tt_local->common.flags &= ~BATADV_TT_CLIENT_WIFI;
 749
 750	/* check the mark in the skb: if it's equal to the configured
 751	 * isolation_mark, it means the packet is coming from an isolated
 752	 * non-mesh client
 753	 */
 754	match_mark = (mark & bat_priv->isolation_mark_mask);
 755	if (bat_priv->isolation_mark_mask &&
 756	    match_mark == bat_priv->isolation_mark)
 757		tt_local->common.flags |= BATADV_TT_CLIENT_ISOLA;
 758	else
 759		tt_local->common.flags &= ~BATADV_TT_CLIENT_ISOLA;
 760
 761	/* if any "dynamic" flag has been modified, resend an ADD event for this
 762	 * entry so that all the nodes can get the new flags
 763	 */
 764	if (remote_flags ^ (tt_local->common.flags & BATADV_TT_REMOTE_MASK))
 765		batadv_tt_local_event(bat_priv, tt_local, BATADV_NO_FLAGS);
 766
 767	ret = true;
 768out:
 769	batadv_hardif_put(in_hardif);
 770	dev_put(in_dev);
 771	batadv_tt_local_entry_put(tt_local);
 772	batadv_tt_global_entry_put(tt_global);
 773	return ret;
 774}
 775
 776/**
 777 * batadv_tt_prepare_tvlv_global_data() - prepare the TVLV TT header to send
 778 *  within a TT Response directed to another node
 779 * @orig_node: originator for which the TT data has to be prepared
 780 * @tt_data: uninitialised pointer to the address of the TVLV buffer
 781 * @tt_change: uninitialised pointer to the address of the area where the TT
 782 *  changed can be stored
 783 * @tt_len: pointer to the length to reserve to the tt_change. if -1 this
 784 *  function reserves the amount of space needed to send the entire global TT
 785 *  table. In case of success the value is updated with the real amount of
 786 *  reserved bytes
 787 * Allocate the needed amount of memory for the entire TT TVLV and write its
 788 * header made up of one tvlv_tt_data object and a series of tvlv_tt_vlan_data
 789 * objects, one per active VLAN served by the originator node.
 790 *
 791 * Return: the size of the allocated buffer or 0 in case of failure.
 792 */
 793static u16
 794batadv_tt_prepare_tvlv_global_data(struct batadv_orig_node *orig_node,
 795				   struct batadv_tvlv_tt_data **tt_data,
 796				   struct batadv_tvlv_tt_change **tt_change,
 797				   s32 *tt_len)
 798{
 799	u16 num_vlan = 0;
 800	u16 num_entries = 0;
 801	u16 tvlv_len = 0;
 802	unsigned int change_offset;
 803	struct batadv_tvlv_tt_vlan_data *tt_vlan;
 804	struct batadv_orig_node_vlan *vlan;
 805	u8 *tt_change_ptr;
 806
 807	spin_lock_bh(&orig_node->vlan_list_lock);
 808	hlist_for_each_entry(vlan, &orig_node->vlan_list, list) {
 809		num_vlan++;
 810		num_entries += atomic_read(&vlan->tt.num_entries);
 811	}
 812
 813	change_offset = struct_size(*tt_data, vlan_data, num_vlan);
 814
 815	/* if tt_len is negative, allocate the space needed by the full table */
 816	if (*tt_len < 0)
 817		*tt_len = batadv_tt_len(num_entries);
 818
 819	if (change_offset > U16_MAX || *tt_len > U16_MAX - change_offset) {
 820		*tt_len = 0;
 821		goto out;
 822	}
 823
 824	tvlv_len = *tt_len;
 825	tvlv_len += change_offset;
 826
 827	*tt_data = kmalloc(tvlv_len, GFP_ATOMIC);
 828	if (!*tt_data) {
 829		*tt_len = 0;
 830		goto out;
 831	}
 832
 833	(*tt_data)->flags = BATADV_NO_FLAGS;
 834	(*tt_data)->ttvn = atomic_read(&orig_node->last_ttvn);
 835	(*tt_data)->num_vlan = htons(num_vlan);
 836
 837	tt_vlan = (*tt_data)->vlan_data;
 838	hlist_for_each_entry(vlan, &orig_node->vlan_list, list) {
 839		tt_vlan->vid = htons(vlan->vid);
 840		tt_vlan->crc = htonl(vlan->tt.crc);
 841		tt_vlan->reserved = 0;
 842
 843		tt_vlan++;
 844	}
 845
 846	tt_change_ptr = (u8 *)*tt_data + change_offset;
 847	*tt_change = (struct batadv_tvlv_tt_change *)tt_change_ptr;
 848
 849out:
 850	spin_unlock_bh(&orig_node->vlan_list_lock);
 851	return tvlv_len;
 852}
 853
 854/**
 855 * batadv_tt_prepare_tvlv_local_data() - allocate and prepare the TT TVLV for
 856 *  this node
 857 * @bat_priv: the bat priv with all the mesh interface information
 858 * @tt_data: uninitialised pointer to the address of the TVLV buffer
 859 * @tt_change: uninitialised pointer to the address of the area where the TT
 860 *  changes can be stored
 861 * @tt_len: pointer to the length to reserve to the tt_change. if -1 this
 862 *  function reserves the amount of space needed to send the entire local TT
 863 *  table. In case of success the value is updated with the real amount of
 864 *  reserved bytes
 865 *
 866 * Allocate the needed amount of memory for the entire TT TVLV and write its
 867 * header made up by one tvlv_tt_data object and a series of tvlv_tt_vlan_data
 868 * objects, one per active VLAN.
 869 *
 870 * Return: the size of the allocated buffer or 0 in case of failure.
 871 */
 872static u16
 873batadv_tt_prepare_tvlv_local_data(struct batadv_priv *bat_priv,
 874				  struct batadv_tvlv_tt_data **tt_data,
 875				  struct batadv_tvlv_tt_change **tt_change,
 876				  s32 *tt_len)
 877{
 878	struct batadv_tvlv_tt_vlan_data *tt_vlan;
 879	struct batadv_meshif_vlan *vlan;
 880	u16 num_vlan = 0;
 881	u16 vlan_entries = 0;
 882	u16 total_entries = 0;
 883	u16 tvlv_len;
 884	u8 *tt_change_ptr;
 885	int change_offset;
 886
 887	spin_lock_bh(&bat_priv->meshif_vlan_list_lock);
 888	hlist_for_each_entry(vlan, &bat_priv->meshif_vlan_list, list) {
 889		vlan_entries = atomic_read(&vlan->tt.num_entries);
 890		if (vlan_entries < 1)
 891			continue;
 892
 893		num_vlan++;
 894		total_entries += vlan_entries;
 895	}
 896
 897	change_offset = struct_size(*tt_data, vlan_data, num_vlan);
 898
 899	/* if tt_len is negative, allocate the space needed by the full table */
 900	if (*tt_len < 0)
 901		*tt_len = batadv_tt_len(total_entries);
 902
 903	tvlv_len = *tt_len;
 904	tvlv_len += change_offset;
 905
 906	*tt_data = kmalloc(tvlv_len, GFP_ATOMIC);
 907	if (!*tt_data) {
 908		tvlv_len = 0;
 909		goto out;
 910	}
 911
 912	(*tt_data)->flags = BATADV_NO_FLAGS;
 913	(*tt_data)->ttvn = atomic_read(&bat_priv->tt.vn);
 914	(*tt_data)->num_vlan = htons(num_vlan);
 915
 916	tt_vlan = (*tt_data)->vlan_data;
 917	hlist_for_each_entry(vlan, &bat_priv->meshif_vlan_list, list) {
 918		vlan_entries = atomic_read(&vlan->tt.num_entries);
 919		if (vlan_entries < 1)
 920			continue;
 921
 922		tt_vlan->vid = htons(vlan->vid);
 923		tt_vlan->crc = htonl(vlan->tt.crc);
 924		tt_vlan->reserved = 0;
 925
 926		tt_vlan++;
 927	}
 928
 929	tt_change_ptr = (u8 *)*tt_data + change_offset;
 930	*tt_change = (struct batadv_tvlv_tt_change *)tt_change_ptr;
 931
 932out:
 933	spin_unlock_bh(&bat_priv->meshif_vlan_list_lock);
 934	return tvlv_len;
 935}
 936
 937/**
 938 * batadv_tt_tvlv_container_update() - update the translation table tvlv
 939 *  container after local tt changes have been committed
 940 * @bat_priv: the bat priv with all the mesh interface information
 941 */
 942static void batadv_tt_tvlv_container_update(struct batadv_priv *bat_priv)
 943{
 944	struct batadv_tt_change_node *entry, *safe;
 945	struct batadv_tvlv_tt_data *tt_data;
 946	struct batadv_tvlv_tt_change *tt_change;
 947	int tt_diff_len, tt_change_len = 0;
 948	int tt_diff_entries_num = 0;
 949	int tt_diff_entries_count = 0;
 950	bool drop_changes = false;
 951	size_t tt_extra_len = 0;
 952	u16 tvlv_len;
 953
 954	tt_diff_entries_num = READ_ONCE(bat_priv->tt.local_changes);
 955	tt_diff_len = batadv_tt_len(tt_diff_entries_num);
 956
 957	/* if we have too many changes for one packet don't send any
 958	 * and wait for the tt table request so we can reply with the full
 959	 * (fragmented) table.
 960	 *
 961	 * The local change history should still be cleaned up so the next
 962	 * TT round can start again with a clean state.
 963	 */
 964	if (tt_diff_len > bat_priv->mesh_iface->mtu) {
 965		tt_diff_len = 0;
 966		tt_diff_entries_num = 0;
 967		drop_changes = true;
 968	}
 969
 970	tvlv_len = batadv_tt_prepare_tvlv_local_data(bat_priv, &tt_data,
 971						     &tt_change, &tt_diff_len);
 972	if (!tvlv_len)
 973		return;
 974
 975	tt_data->flags = BATADV_TT_OGM_DIFF;
 976
 977	if (!drop_changes && tt_diff_len == 0)
 978		goto container_register;
 979
 980	spin_lock_bh(&bat_priv->tt.changes_list_lock);
 981	WRITE_ONCE(bat_priv->tt.local_changes, 0);
 982
 983	list_for_each_entry_safe(entry, safe, &bat_priv->tt.changes_list,
 984				 list) {
 985		if (tt_diff_entries_count < tt_diff_entries_num) {
 986			memcpy(tt_change + tt_diff_entries_count,
 987			       &entry->change,
 988			       sizeof(struct batadv_tvlv_tt_change));
 989			tt_diff_entries_count++;
 990		}
 991		list_del(&entry->list);
 992		kmem_cache_free(batadv_tt_change_cache, entry);
 993	}
 994	spin_unlock_bh(&bat_priv->tt.changes_list_lock);
 995
 996	tt_extra_len = batadv_tt_len(tt_diff_entries_num -
 997				     tt_diff_entries_count);
 998
 999	/* Keep the buffer for possible tt_request */
1000	spin_lock_bh(&bat_priv->tt.last_changeset_lock);
1001	kfree(bat_priv->tt.last_changeset);
1002	bat_priv->tt.last_changeset_len = 0;
1003	bat_priv->tt.last_changeset = NULL;
1004	tt_change_len = batadv_tt_len(tt_diff_entries_count);
1005	/* check whether this new OGM has no changes due to size problems */
1006	if (tt_diff_entries_count > 0) {
1007		tt_diff_len -= tt_extra_len;
1008		/* if kmalloc() fails we will reply with the full table
1009		 * instead of providing the diff
1010		 */
1011		bat_priv->tt.last_changeset = kzalloc(tt_diff_len, GFP_ATOMIC);
1012		if (bat_priv->tt.last_changeset) {
1013			memcpy(bat_priv->tt.last_changeset,
1014			       tt_change, tt_change_len);
1015			bat_priv->tt.last_changeset_len = tt_diff_len;
1016		}
1017	}
1018	spin_unlock_bh(&bat_priv->tt.last_changeset_lock);
1019
1020	/* Remove extra packet space for OGM */
1021	tvlv_len -= tt_extra_len;
1022container_register:
1023	batadv_tvlv_container_register(bat_priv, BATADV_TVLV_TT, 1, tt_data,
1024				       tvlv_len);
1025	kfree(tt_data);
1026}
1027
1028/**
1029 * batadv_tt_local_dump_entry() - Dump one TT local entry into a message
1030 * @msg :Netlink message to dump into
1031 * @portid: Port making netlink request
1032 * @cb: Control block containing additional options
1033 * @bat_priv: The bat priv with all the mesh interface information
1034 * @common: tt local & tt global common data
1035 *
1036 * Return: Error code, or 0 on success
1037 */
1038static int
1039batadv_tt_local_dump_entry(struct sk_buff *msg, u32 portid,
1040			   struct netlink_callback *cb,
1041			   struct batadv_priv *bat_priv,
1042			   struct batadv_tt_common_entry *common)
1043{
1044	void *hdr;
1045	struct batadv_meshif_vlan *vlan;
1046	struct batadv_tt_local_entry *local;
1047	unsigned int last_seen_msecs;
1048	u32 crc;
1049
1050	local = container_of(common, struct batadv_tt_local_entry, common);
1051	last_seen_msecs = jiffies_to_msecs(jiffies - local->last_seen);
1052
1053	vlan = batadv_meshif_vlan_get(bat_priv, common->vid);
1054	if (!vlan)
1055		return 0;
1056
1057	crc = vlan->tt.crc;
1058
1059	batadv_meshif_vlan_put(vlan);
1060
1061	hdr = genlmsg_put(msg, portid, cb->nlh->nlmsg_seq,
1062			  &batadv_netlink_family,  NLM_F_MULTI,
1063			  BATADV_CMD_GET_TRANSTABLE_LOCAL);
1064	if (!hdr)
1065		return -ENOBUFS;
1066
1067	genl_dump_check_consistent(cb, hdr);
1068
1069	if (nla_put(msg, BATADV_ATTR_TT_ADDRESS, ETH_ALEN, common->addr) ||
1070	    nla_put_u32(msg, BATADV_ATTR_TT_CRC32, crc) ||
1071	    nla_put_u16(msg, BATADV_ATTR_TT_VID, common->vid) ||
1072	    nla_put_u32(msg, BATADV_ATTR_TT_FLAGS, common->flags))
1073		goto nla_put_failure;
1074
1075	if (!(common->flags & BATADV_TT_CLIENT_NOPURGE) &&
1076	    nla_put_u32(msg, BATADV_ATTR_LAST_SEEN_MSECS, last_seen_msecs))
1077		goto nla_put_failure;
1078
1079	genlmsg_end(msg, hdr);
1080	return 0;
1081
1082 nla_put_failure:
1083	genlmsg_cancel(msg, hdr);
1084	return -EMSGSIZE;
1085}
1086
1087/**
1088 * batadv_tt_local_dump_bucket() - Dump one TT local bucket into a message
1089 * @msg: Netlink message to dump into
1090 * @portid: Port making netlink request
1091 * @cb: Control block containing additional options
1092 * @bat_priv: The bat priv with all the mesh interface information
1093 * @hash: hash to dump
1094 * @bucket: bucket index to dump
1095 * @idx_s: Number of entries to skip
1096 *
1097 * Return: Error code, or 0 on success
1098 */
1099static int
1100batadv_tt_local_dump_bucket(struct sk_buff *msg, u32 portid,
1101			    struct netlink_callback *cb,
1102			    struct batadv_priv *bat_priv,
1103			    struct batadv_hashtable *hash, unsigned int bucket,
1104			    int *idx_s)
1105{
1106	struct batadv_tt_common_entry *common;
1107	int idx = 0;
1108
1109	spin_lock_bh(&hash->list_locks[bucket]);
1110	cb->seq = atomic_read(&hash->generation) << 1 | 1;
1111
1112	hlist_for_each_entry(common, &hash->table[bucket], hash_entry) {
1113		if (idx++ < *idx_s)
1114			continue;
1115
1116		if (batadv_tt_local_dump_entry(msg, portid, cb, bat_priv,
1117					       common)) {
1118			spin_unlock_bh(&hash->list_locks[bucket]);
1119			*idx_s = idx - 1;
1120			return -EMSGSIZE;
1121		}
1122	}
1123	spin_unlock_bh(&hash->list_locks[bucket]);
1124
1125	*idx_s = 0;
1126	return 0;
1127}
1128
1129/**
1130 * batadv_tt_local_dump() - Dump TT local entries into a message
1131 * @msg: Netlink message to dump into
1132 * @cb: Parameters from query
1133 *
1134 * Return: Error code, or 0 on success
1135 */
1136int batadv_tt_local_dump(struct sk_buff *msg, struct netlink_callback *cb)
1137{
1138	struct net_device *mesh_iface;
1139	struct batadv_priv *bat_priv;
1140	struct batadv_hard_iface *primary_if = NULL;
1141	struct batadv_hashtable *hash;
1142	int ret;
1143	int bucket = cb->args[0];
1144	int idx = cb->args[1];
1145	int portid = NETLINK_CB(cb->skb).portid;
1146
1147	mesh_iface = batadv_netlink_get_meshif(cb);
1148	if (IS_ERR(mesh_iface))
1149		return PTR_ERR(mesh_iface);
1150
1151	bat_priv = netdev_priv(mesh_iface);
1152
1153	primary_if = batadv_primary_if_get_selected(bat_priv);
1154	if (!primary_if || primary_if->if_status != BATADV_IF_ACTIVE) {
1155		ret = -ENOENT;
1156		goto out;
1157	}
1158
1159	hash = bat_priv->tt.local_hash;
1160
1161	while (bucket < hash->size) {
1162		if (batadv_tt_local_dump_bucket(msg, portid, cb, bat_priv,
1163						hash, bucket, &idx))
1164			break;
1165
1166		bucket++;
1167	}
1168
1169	ret = msg->len;
1170
1171 out:
1172	batadv_hardif_put(primary_if);
1173	dev_put(mesh_iface);
1174
1175	cb->args[0] = bucket;
1176	cb->args[1] = idx;
1177
1178	return ret;
1179}
1180
1181static void
1182batadv_tt_local_set_pending(struct batadv_priv *bat_priv,
1183			    struct batadv_tt_local_entry *tt_local_entry,
1184			    u16 flags, const char *message)
1185{
1186	batadv_tt_local_event(bat_priv, tt_local_entry, flags);
1187
1188	/* The local client has to be marked as "pending to be removed" but has
1189	 * to be kept in the table in order to send it in a full table
1190	 * response issued before the net ttvn increment (consistency check)
1191	 */
1192	tt_local_entry->common.flags |= BATADV_TT_CLIENT_PENDING;
1193
1194	batadv_dbg(BATADV_DBG_TT, bat_priv,
1195		   "Local tt entry (%pM, vid: %d) pending to be removed: %s\n",
1196		   tt_local_entry->common.addr,
1197		   batadv_print_vid(tt_local_entry->common.vid), message);
1198}
1199
1200/**
1201 * batadv_tt_local_remove() - logically remove an entry from the local table
1202 * @bat_priv: the bat priv with all the mesh interface information
1203 * @addr: the MAC address of the client to remove
1204 * @vid: VLAN identifier
1205 * @message: message to append to the log on deletion
1206 * @roaming: true if the deletion is due to a roaming event
1207 *
1208 * Return: the flags assigned to the local entry before being deleted
1209 */
1210u16 batadv_tt_local_remove(struct batadv_priv *bat_priv, const u8 *addr,
1211			   unsigned short vid, const char *message,
1212			   bool roaming)
1213{
1214	struct batadv_tt_local_entry *tt_removed_entry;
1215	struct batadv_tt_local_entry *tt_local_entry;
1216	u16 flags, curr_flags = BATADV_NO_FLAGS;
1217	struct hlist_node *tt_removed_node;
1218
1219	tt_local_entry = batadv_tt_local_hash_find(bat_priv, addr, vid);
1220	if (!tt_local_entry)
1221		goto out;
1222
1223	curr_flags = tt_local_entry->common.flags;
1224
1225	flags = BATADV_TT_CLIENT_DEL;
1226	/* if this global entry addition is due to a roaming, the node has to
1227	 * mark the local entry as "roamed" in order to correctly reroute
1228	 * packets later
1229	 */
1230	if (roaming) {
1231		flags |= BATADV_TT_CLIENT_ROAM;
1232		/* mark the local client as ROAMed */
1233		tt_local_entry->common.flags |= BATADV_TT_CLIENT_ROAM;
1234	}
1235
1236	if (!(tt_local_entry->common.flags & BATADV_TT_CLIENT_NEW)) {
1237		batadv_tt_local_set_pending(bat_priv, tt_local_entry, flags,
1238					    message);
1239		goto out;
1240	}
1241	/* if this client has been added right now, it is possible to
1242	 * immediately purge it
1243	 */
1244	batadv_tt_local_event(bat_priv, tt_local_entry, BATADV_TT_CLIENT_DEL);
1245
1246	tt_removed_node = batadv_hash_remove(bat_priv->tt.local_hash,
1247					     batadv_compare_tt,
1248					     batadv_choose_tt,
1249					     &tt_local_entry->common);
1250	if (!tt_removed_node)
1251		goto out;
1252
1253	/* drop reference of remove hash entry */
1254	tt_removed_entry = hlist_entry(tt_removed_node,
1255				       struct batadv_tt_local_entry,
1256				       common.hash_entry);
1257	batadv_tt_local_entry_put(tt_removed_entry);
1258
1259out:
1260	batadv_tt_local_entry_put(tt_local_entry);
1261
1262	return curr_flags;
1263}
1264
1265/**
1266 * batadv_tt_local_purge_list() - purge inactive tt local entries
1267 * @bat_priv: the bat priv with all the mesh interface information
1268 * @head: pointer to the list containing the local tt entries
1269 * @timeout: parameter deciding whether a given tt local entry is considered
1270 *  inactive or not
1271 */
1272static void batadv_tt_local_purge_list(struct batadv_priv *bat_priv,
1273				       struct hlist_head *head,
1274				       int timeout)
1275{
1276	struct batadv_tt_local_entry *tt_local_entry;
1277	struct batadv_tt_common_entry *tt_common_entry;
1278	struct hlist_node *node_tmp;
1279
1280	hlist_for_each_entry_safe(tt_common_entry, node_tmp, head,
1281				  hash_entry) {
1282		tt_local_entry = container_of(tt_common_entry,
1283					      struct batadv_tt_local_entry,
1284					      common);
1285		if (tt_local_entry->common.flags & BATADV_TT_CLIENT_NOPURGE)
1286			continue;
1287
1288		/* entry already marked for deletion */
1289		if (tt_local_entry->common.flags & BATADV_TT_CLIENT_PENDING)
1290			continue;
1291
1292		if (!batadv_has_timed_out(tt_local_entry->last_seen, timeout))
1293			continue;
1294
1295		batadv_tt_local_set_pending(bat_priv, tt_local_entry,
1296					    BATADV_TT_CLIENT_DEL, "timed out");
1297	}
1298}
1299
1300/**
1301 * batadv_tt_local_purge() - purge inactive tt local entries
1302 * @bat_priv: the bat priv with all the mesh interface information
1303 * @timeout: parameter deciding whether a given tt local entry is considered
1304 *  inactive or not
1305 */
1306static void batadv_tt_local_purge(struct batadv_priv *bat_priv,
1307				  int timeout)
1308{
1309	struct batadv_hashtable *hash = bat_priv->tt.local_hash;
1310	struct hlist_head *head;
1311	spinlock_t *list_lock; /* protects write access to the hash lists */
1312	u32 i;
1313
1314	for (i = 0; i < hash->size; i++) {
1315		head = &hash->table[i];
1316		list_lock = &hash->list_locks[i];
1317
1318		spin_lock_bh(list_lock);
1319		batadv_tt_local_purge_list(bat_priv, head, timeout);
1320		spin_unlock_bh(list_lock);
1321	}
1322}
1323
1324static void batadv_tt_local_table_free(struct batadv_priv *bat_priv)
1325{
1326	struct batadv_hashtable *hash;
1327	spinlock_t *list_lock; /* protects write access to the hash lists */
1328	struct batadv_tt_common_entry *tt_common_entry;
1329	struct batadv_tt_local_entry *tt_local;
1330	struct hlist_node *node_tmp;
1331	struct hlist_head *head;
1332	u32 i;
1333
1334	if (!bat_priv->tt.local_hash)
1335		return;
1336
1337	hash = bat_priv->tt.local_hash;
1338
1339	for (i = 0; i < hash->size; i++) {
1340		head = &hash->table[i];
1341		list_lock = &hash->list_locks[i];
1342
1343		spin_lock_bh(list_lock);
1344		hlist_for_each_entry_safe(tt_common_entry, node_tmp,
1345					  head, hash_entry) {
1346			hlist_del_rcu(&tt_common_entry->hash_entry);
1347			tt_local = container_of(tt_common_entry,
1348						struct batadv_tt_local_entry,
1349						common);
1350
1351			batadv_tt_local_entry_put(tt_local);
1352		}
1353		spin_unlock_bh(list_lock);
1354	}
1355
1356	batadv_hash_destroy(hash);
1357
1358	bat_priv->tt.local_hash = NULL;
1359}
1360
1361static int batadv_tt_global_init(struct batadv_priv *bat_priv)
1362{
1363	if (bat_priv->tt.global_hash)
1364		return 0;
1365
1366	bat_priv->tt.global_hash = batadv_hash_new(1024);
1367
1368	if (!bat_priv->tt.global_hash)
1369		return -ENOMEM;
1370
1371	batadv_hash_set_lock_class(bat_priv->tt.global_hash,
1372				   &batadv_tt_global_hash_lock_class_key);
1373
1374	return 0;
1375}
1376
1377static void batadv_tt_changes_list_free(struct batadv_priv *bat_priv)
1378{
1379	struct batadv_tt_change_node *entry, *safe;
1380
1381	spin_lock_bh(&bat_priv->tt.changes_list_lock);
1382
1383	list_for_each_entry_safe(entry, safe, &bat_priv->tt.changes_list,
1384				 list) {
1385		list_del(&entry->list);
1386		kmem_cache_free(batadv_tt_change_cache, entry);
1387	}
1388
1389	WRITE_ONCE(bat_priv->tt.local_changes, 0);
1390	spin_unlock_bh(&bat_priv->tt.changes_list_lock);
1391}
1392
1393/**
1394 * batadv_tt_global_orig_entry_find() - find a TT orig_list_entry
1395 * @entry: the TT global entry where the orig_list_entry has to be
1396 *  extracted from
1397 * @orig_node: the originator for which the orig_list_entry has to be found
1398 *
1399 * retrieve the orig_tt_list_entry belonging to orig_node from the
1400 * batadv_tt_global_entry list
1401 *
1402 * Return: it with an increased refcounter, NULL if not found
1403 */
1404static struct batadv_tt_orig_list_entry *
1405batadv_tt_global_orig_entry_find(const struct batadv_tt_global_entry *entry,
1406				 const struct batadv_orig_node *orig_node)
1407{
1408	struct batadv_tt_orig_list_entry *tmp_orig_entry, *orig_entry = NULL;
1409	const struct hlist_head *head;
1410
1411	rcu_read_lock();
1412	head = &entry->orig_list;
1413	hlist_for_each_entry_rcu(tmp_orig_entry, head, list) {
1414		if (tmp_orig_entry->orig_node != orig_node)
1415			continue;
1416		if (!kref_get_unless_zero(&tmp_orig_entry->refcount))
1417			continue;
1418
1419		orig_entry = tmp_orig_entry;
1420		break;
1421	}
1422	rcu_read_unlock();
1423
1424	return orig_entry;
1425}
1426
1427/**
1428 * batadv_tt_global_entry_has_orig() - check if a TT global entry is also
1429 *  handled by a given originator
1430 * @entry: the TT global entry to check
1431 * @orig_node: the originator to search in the list
1432 * @flags: a pointer to store TT flags for the given @entry received
1433 *  from @orig_node
1434 *
1435 * find out if an orig_node is already in the list of a tt_global_entry.
1436 *
1437 * Return: true if found, false otherwise
1438 */
1439static bool
1440batadv_tt_global_entry_has_orig(const struct batadv_tt_global_entry *entry,
1441				const struct batadv_orig_node *orig_node,
1442				u8 *flags)
1443{
1444	struct batadv_tt_orig_list_entry *orig_entry;
1445	bool found = false;
1446
1447	orig_entry = batadv_tt_global_orig_entry_find(entry, orig_node);
1448	if (orig_entry) {
1449		found = true;
1450
1451		if (flags)
1452			*flags = orig_entry->flags;
1453
1454		batadv_tt_orig_list_entry_put(orig_entry);
1455	}
1456
1457	return found;
1458}
1459
1460/**
1461 * batadv_tt_global_sync_flags() - update TT sync flags
1462 * @tt_global: the TT global entry to update sync flags in
1463 *
1464 * Updates the sync flag bits in the tt_global flag attribute with a logical
1465 * OR of all sync flags from any of its TT orig entries.
1466 */
1467static void
1468batadv_tt_global_sync_flags(struct batadv_tt_global_entry *tt_global)
1469{
1470	struct batadv_tt_orig_list_entry *orig_entry;
1471	const struct hlist_head *head;
1472	u16 flags = BATADV_NO_FLAGS;
1473
1474	rcu_read_lock();
1475	head = &tt_global->orig_list;
1476	hlist_for_each_entry_rcu(orig_entry, head, list)
1477		flags |= orig_entry->flags;
1478	rcu_read_unlock();
1479
1480	flags |= tt_global->common.flags & (~BATADV_TT_SYNC_MASK);
1481	tt_global->common.flags = flags;
1482}
1483
1484/**
1485 * batadv_tt_global_orig_entry_add() - add or update a TT orig entry
1486 * @tt_global: the TT global entry to add an orig entry in
1487 * @orig_node: the originator to add an orig entry for
1488 * @ttvn: translation table version number of this changeset
1489 * @flags: TT sync flags
1490 */
1491static void
1492batadv_tt_global_orig_entry_add(struct batadv_tt_global_entry *tt_global,
1493				struct batadv_orig_node *orig_node, int ttvn,
1494				u8 flags)
1495{
1496	struct batadv_tt_orig_list_entry *orig_entry;
1497
1498	spin_lock_bh(&tt_global->list_lock);
1499
1500	orig_entry = batadv_tt_global_orig_entry_find(tt_global, orig_node);
1501	if (orig_entry) {
1502		/* refresh the ttvn: the current value could be a bogus one that
1503		 * was added during a "temporary client detection"
1504		 */
1505		orig_entry->ttvn = ttvn;
1506		orig_entry->flags = flags;
1507		goto sync_flags;
1508	}
1509
1510	orig_entry = kmem_cache_zalloc(batadv_tt_orig_cache, GFP_ATOMIC);
1511	if (!orig_entry)
1512		goto out;
1513
1514	INIT_HLIST_NODE(&orig_entry->list);
1515	kref_get(&orig_node->refcount);
1516	batadv_tt_global_size_inc(orig_node, tt_global->common.vid);
1517	orig_entry->orig_node = orig_node;
1518	orig_entry->ttvn = ttvn;
1519	orig_entry->flags = flags;
1520	kref_init(&orig_entry->refcount);
1521
1522	kref_get(&orig_entry->refcount);
1523	hlist_add_head_rcu(&orig_entry->list,
1524			   &tt_global->orig_list);
1525	atomic_inc(&tt_global->orig_list_count);
1526
1527sync_flags:
1528	batadv_tt_global_sync_flags(tt_global);
1529out:
1530	batadv_tt_orig_list_entry_put(orig_entry);
1531
1532	spin_unlock_bh(&tt_global->list_lock);
1533}
1534
1535/**
1536 * batadv_tt_global_add() - add a new TT global entry or update an existing one
1537 * @bat_priv: the bat priv with all the mesh interface information
1538 * @orig_node: the originator announcing the client
1539 * @tt_addr: the mac address of the non-mesh client
1540 * @vid: VLAN identifier
1541 * @flags: TT flags that have to be set for this non-mesh client
1542 * @ttvn: the tt version number ever announcing this non-mesh client
1543 *
1544 * Add a new TT global entry for the given originator. If the entry already
1545 * exists add a new reference to the given originator (a global entry can have
1546 * references to multiple originators) and adjust the flags attribute to reflect
1547 * the function argument.
1548 * If a TT local entry exists for this non-mesh client remove it.
1549 *
1550 * The caller must hold the orig_node refcount.
1551 *
1552 * Return: true if the new entry has been added, false otherwise
1553 */
1554static bool batadv_tt_global_add(struct batadv_priv *bat_priv,
1555				 struct batadv_orig_node *orig_node,
1556				 const unsigned char *tt_addr,
1557				 unsigned short vid, u16 flags, u8 ttvn)
1558{
1559	struct batadv_tt_global_entry *tt_global_entry;
1560	struct batadv_tt_local_entry *tt_local_entry;
1561	bool ret = false;
1562	int hash_added;
1563	struct batadv_tt_common_entry *common;
1564	u16 local_flags;
1565
1566	/* ignore global entries from backbone nodes */
1567	if (batadv_bla_is_backbone_gw_orig(bat_priv, orig_node->orig, vid))
1568		return true;
1569
1570	tt_global_entry = batadv_tt_global_hash_find(bat_priv, tt_addr, vid);
1571	tt_local_entry = batadv_tt_local_hash_find(bat_priv, tt_addr, vid);
1572
1573	/* if the node already has a local client for this entry, it has to wait
1574	 * for a roaming advertisement instead of manually messing up the global
1575	 * table
1576	 */
1577	if ((flags & BATADV_TT_CLIENT_TEMP) && tt_local_entry &&
1578	    !(tt_local_entry->common.flags & BATADV_TT_CLIENT_NEW))
1579		goto out;
1580
1581	if (!tt_global_entry) {
1582		tt_global_entry = kmem_cache_zalloc(batadv_tg_cache,
1583						    GFP_ATOMIC);
1584		if (!tt_global_entry)
1585			goto out;
1586
1587		common = &tt_global_entry->common;
1588		ether_addr_copy(common->addr, tt_addr);
1589		common->vid = vid;
1590
1591		if (!is_multicast_ether_addr(common->addr))
1592			common->flags = flags & (~BATADV_TT_SYNC_MASK);
1593
1594		tt_global_entry->roam_at = 0;
1595		/* node must store current time in case of roaming. This is
1596		 * needed to purge this entry out on timeout (if nobody claims
1597		 * it)
1598		 */
1599		if (flags & BATADV_TT_CLIENT_ROAM)
1600			tt_global_entry->roam_at = jiffies;
1601		kref_init(&common->refcount);
1602		common->added_at = jiffies;
1603
1604		INIT_HLIST_HEAD(&tt_global_entry->orig_list);
1605		atomic_set(&tt_global_entry->orig_list_count, 0);
1606		spin_lock_init(&tt_global_entry->list_lock);
1607
1608		kref_get(&common->refcount);
1609		hash_added = batadv_hash_add(bat_priv->tt.global_hash,
1610					     batadv_compare_tt,
1611					     batadv_choose_tt, common,
1612					     &common->hash_entry);
1613
1614		if (unlikely(hash_added != 0)) {
1615			/* remove the reference for the hash */
1616			batadv_tt_global_entry_put(tt_global_entry);
1617			goto out_remove;
1618		}
1619	} else {
1620		common = &tt_global_entry->common;
1621		/* If there is already a global entry, we can use this one for
1622		 * our processing.
1623		 * But if we are trying to add a temporary client then here are
1624		 * two options at this point:
1625		 * 1) the global client is not a temporary client: the global
1626		 *    client has to be left as it is, temporary information
1627		 *    should never override any already known client state
1628		 * 2) the global client is a temporary client: purge the
1629		 *    originator list and add the new one orig_entry
1630		 */
1631		if (flags & BATADV_TT_CLIENT_TEMP) {
1632			if (!(common->flags & BATADV_TT_CLIENT_TEMP))
1633				goto out;
1634			if (batadv_tt_global_entry_has_orig(tt_global_entry,
1635							    orig_node, NULL))
1636				goto out_remove;
1637			batadv_tt_global_del_orig_list(tt_global_entry);
1638			goto add_orig_entry;
1639		}
1640
1641		/* if the client was temporary added before receiving the first
1642		 * OGM announcing it, we have to clear the TEMP flag. Also,
1643		 * remove the previous temporary orig node and re-add it
1644		 * if required. If the orig entry changed, the new one which
1645		 * is a non-temporary entry is preferred.
1646		 */
1647		if (common->flags & BATADV_TT_CLIENT_TEMP) {
1648			batadv_tt_global_del_orig_list(tt_global_entry);
1649			common->flags &= ~BATADV_TT_CLIENT_TEMP;
1650		}
1651
1652		/* the change can carry possible "attribute" flags like the
1653		 * TT_CLIENT_TEMP, therefore they have to be copied in the
1654		 * client entry
1655		 */
1656		if (!is_multicast_ether_addr(common->addr))
1657			common->flags |= flags & (~BATADV_TT_SYNC_MASK);
1658
1659		/* If there is the BATADV_TT_CLIENT_ROAM flag set, there is only
1660		 * one originator left in the list and we previously received a
1661		 * delete + roaming change for this originator.
1662		 *
1663		 * We should first delete the old originator before adding the
1664		 * new one.
1665		 */
1666		if (common->flags & BATADV_TT_CLIENT_ROAM) {
1667			batadv_tt_global_del_orig_list(tt_global_entry);
1668			common->flags &= ~BATADV_TT_CLIENT_ROAM;
1669			tt_global_entry->roam_at = 0;
1670		}
1671	}
1672add_orig_entry:
1673	/* add the new orig_entry (if needed) or update it */
1674	batadv_tt_global_orig_entry_add(tt_global_entry, orig_node, ttvn,
1675					flags & BATADV_TT_SYNC_MASK);
1676
1677	batadv_dbg(BATADV_DBG_TT, bat_priv,
1678		   "Creating new global tt entry: %pM (vid: %d, via %pM)\n",
1679		   common->addr, batadv_print_vid(common->vid),
1680		   orig_node->orig);
1681	ret = true;
1682
1683out_remove:
1684	/* Do not remove multicast addresses from the local hash on
1685	 * global additions
1686	 */
1687	if (is_multicast_ether_addr(tt_addr))
1688		goto out;
1689
1690	/* remove address from local hash if present */
1691	local_flags = batadv_tt_local_remove(bat_priv, tt_addr, vid,
1692					     "global tt received",
1693					     flags & BATADV_TT_CLIENT_ROAM);
1694	tt_global_entry->common.flags |= local_flags & BATADV_TT_CLIENT_WIFI;
1695
1696	if (!(flags & BATADV_TT_CLIENT_ROAM))
1697		/* this is a normal global add. Therefore the client is not in a
1698		 * roaming state anymore.
1699		 */
1700		tt_global_entry->common.flags &= ~BATADV_TT_CLIENT_ROAM;
1701
1702out:
1703	batadv_tt_global_entry_put(tt_global_entry);
1704	batadv_tt_local_entry_put(tt_local_entry);
1705	return ret;
1706}
1707
1708/**
1709 * batadv_transtable_best_orig() - Get best originator list entry from tt entry
1710 * @bat_priv: the bat priv with all the mesh interface information
1711 * @tt_global_entry: global translation table entry to be analyzed
1712 *
1713 * This function assumes the caller holds rcu_read_lock().
1714 * Return: best originator list entry or NULL on errors.
1715 */
1716static struct batadv_tt_orig_list_entry *
1717batadv_transtable_best_orig(struct batadv_priv *bat_priv,
1718			    struct batadv_tt_global_entry *tt_global_entry)
1719{
1720	struct batadv_neigh_node *router, *best_router = NULL;
1721	struct batadv_algo_ops *bao = bat_priv->algo_ops;
1722	struct hlist_head *head;
1723	struct batadv_tt_orig_list_entry *orig_entry, *best_entry = NULL;
1724
1725	head = &tt_global_entry->orig_list;
1726	hlist_for_each_entry_rcu(orig_entry, head, list) {
1727		router = batadv_orig_router_get(orig_entry->orig_node,
1728						BATADV_IF_DEFAULT);
1729		if (!router)
1730			continue;
1731
1732		if (best_router &&
1733		    bao->neigh.cmp(router, BATADV_IF_DEFAULT, best_router,
1734				   BATADV_IF_DEFAULT) <= 0) {
1735			batadv_neigh_node_put(router);
1736			continue;
1737		}
1738
1739		/* release the refcount for the "old" best */
1740		batadv_neigh_node_put(best_router);
1741
1742		best_entry = orig_entry;
1743		best_router = router;
1744	}
1745
1746	batadv_neigh_node_put(best_router);
1747
1748	return best_entry;
1749}
1750
1751/**
1752 * batadv_tt_global_dump_subentry() - Dump all TT local entries into a message
1753 * @msg: Netlink message to dump into
1754 * @portid: Port making netlink request
1755 * @seq: Sequence number of netlink message
1756 * @common: tt local & tt global common data
1757 * @orig: Originator node announcing a non-mesh client
1758 * @best: Is the best originator for the TT entry
1759 *
1760 * Return: Error code, or 0 on success
1761 */
1762static int
1763batadv_tt_global_dump_subentry(struct sk_buff *msg, u32 portid, u32 seq,
1764			       struct batadv_tt_common_entry *common,
1765			       struct batadv_tt_orig_list_entry *orig,
1766			       bool best)
1767{
1768	u16 flags = (common->flags & (~BATADV_TT_SYNC_MASK)) | orig->flags;
1769	void *hdr;
1770	struct batadv_orig_node_vlan *vlan;
1771	u8 last_ttvn;
1772	u32 crc;
1773
1774	vlan = batadv_orig_node_vlan_get(orig->orig_node,
1775					 common->vid);
1776	if (!vlan)
1777		return 0;
1778
1779	crc = vlan->tt.crc;
1780
1781	batadv_orig_node_vlan_put(vlan);
1782
1783	hdr = genlmsg_put(msg, portid, seq, &batadv_netlink_family,
1784			  NLM_F_MULTI,
1785			  BATADV_CMD_GET_TRANSTABLE_GLOBAL);
1786	if (!hdr)
1787		return -ENOBUFS;
1788
1789	last_ttvn = atomic_read(&orig->orig_node->last_ttvn);
1790
1791	if (nla_put(msg, BATADV_ATTR_TT_ADDRESS, ETH_ALEN, common->addr) ||
1792	    nla_put(msg, BATADV_ATTR_ORIG_ADDRESS, ETH_ALEN,
1793		    orig->orig_node->orig) ||
1794	    nla_put_u8(msg, BATADV_ATTR_TT_TTVN, orig->ttvn) ||
1795	    nla_put_u8(msg, BATADV_ATTR_TT_LAST_TTVN, last_ttvn) ||
1796	    nla_put_u32(msg, BATADV_ATTR_TT_CRC32, crc) ||
1797	    nla_put_u16(msg, BATADV_ATTR_TT_VID, common->vid) ||
1798	    nla_put_u32(msg, BATADV_ATTR_TT_FLAGS, flags))
1799		goto nla_put_failure;
1800
1801	if (best && nla_put_flag(msg, BATADV_ATTR_FLAG_BEST))
1802		goto nla_put_failure;
1803
1804	genlmsg_end(msg, hdr);
1805	return 0;
1806
1807 nla_put_failure:
1808	genlmsg_cancel(msg, hdr);
1809	return -EMSGSIZE;
1810}
1811
1812/**
1813 * batadv_tt_global_dump_entry() - Dump one TT global entry into a message
1814 * @msg: Netlink message to dump into
1815 * @portid: Port making netlink request
1816 * @seq: Sequence number of netlink message
1817 * @bat_priv: The bat priv with all the mesh interface information
1818 * @common: tt local & tt global common data
1819 * @sub_s: Number of entries to skip
1820 *
1821 * This function assumes the caller holds rcu_read_lock().
1822 *
1823 * Return: Error code, or 0 on success
1824 */
1825static int
1826batadv_tt_global_dump_entry(struct sk_buff *msg, u32 portid, u32 seq,
1827			    struct batadv_priv *bat_priv,
1828			    struct batadv_tt_common_entry *common, int *sub_s)
1829{
1830	struct batadv_tt_orig_list_entry *orig_entry, *best_entry;
1831	struct batadv_tt_global_entry *global;
1832	struct hlist_head *head;
1833	int sub = 0;
1834	bool best;
1835
1836	global = container_of(common, struct batadv_tt_global_entry, common);
1837	best_entry = batadv_transtable_best_orig(bat_priv, global);
1838	head = &global->orig_list;
1839
1840	hlist_for_each_entry_rcu(orig_entry, head, list) {
1841		if (sub++ < *sub_s)
1842			continue;
1843
1844		best = (orig_entry == best_entry);
1845
1846		if (batadv_tt_global_dump_subentry(msg, portid, seq, common,
1847						   orig_entry, best)) {
1848			*sub_s = sub - 1;
1849			return -EMSGSIZE;
1850		}
1851	}
1852
1853	*sub_s = 0;
1854	return 0;
1855}
1856
1857/**
1858 * batadv_tt_global_dump_bucket() - Dump one TT local bucket into a message
1859 * @msg: Netlink message to dump into
1860 * @portid: Port making netlink request
1861 * @seq: Sequence number of netlink message
1862 * @bat_priv: The bat priv with all the mesh interface information
1863 * @head: Pointer to the list containing the global tt entries
1864 * @idx_s: Number of entries to skip
1865 * @sub: Number of entries to skip
1866 *
1867 * Return: Error code, or 0 on success
1868 */
1869static int
1870batadv_tt_global_dump_bucket(struct sk_buff *msg, u32 portid, u32 seq,
1871			     struct batadv_priv *bat_priv,
1872			     struct hlist_head *head, int *idx_s, int *sub)
1873{
1874	struct batadv_tt_common_entry *common;
1875	int idx = 0;
1876
1877	rcu_read_lock();
1878	hlist_for_each_entry_rcu(common, head, hash_entry) {
1879		if (idx++ < *idx_s)
1880			continue;
1881
1882		if (batadv_tt_global_dump_entry(msg, portid, seq, bat_priv,
1883						common, sub)) {
1884			rcu_read_unlock();
1885			*idx_s = idx - 1;
1886			return -EMSGSIZE;
1887		}
1888	}
1889	rcu_read_unlock();
1890
1891	*idx_s = 0;
1892	*sub = 0;
1893	return 0;
1894}
1895
1896/**
1897 * batadv_tt_global_dump() -  Dump TT global entries into a message
1898 * @msg: Netlink message to dump into
1899 * @cb: Parameters from query
1900 *
1901 * Return: Error code, or length of message on success
1902 */
1903int batadv_tt_global_dump(struct sk_buff *msg, struct netlink_callback *cb)
1904{
1905	struct net_device *mesh_iface;
1906	struct batadv_priv *bat_priv;
1907	struct batadv_hard_iface *primary_if = NULL;
1908	struct batadv_hashtable *hash;
1909	struct hlist_head *head;
1910	int ret;
1911	int bucket = cb->args[0];
1912	int idx = cb->args[1];
1913	int sub = cb->args[2];
1914	int portid = NETLINK_CB(cb->skb).portid;
1915
1916	mesh_iface = batadv_netlink_get_meshif(cb);
1917	if (IS_ERR(mesh_iface))
1918		return PTR_ERR(mesh_iface);
1919
1920	bat_priv = netdev_priv(mesh_iface);
1921
1922	primary_if = batadv_primary_if_get_selected(bat_priv);
1923	if (!primary_if || primary_if->if_status != BATADV_IF_ACTIVE) {
1924		ret = -ENOENT;
1925		goto out;
1926	}
1927
1928	hash = bat_priv->tt.global_hash;
1929
1930	while (bucket < hash->size) {
1931		head = &hash->table[bucket];
1932
1933		if (batadv_tt_global_dump_bucket(msg, portid,
1934						 cb->nlh->nlmsg_seq, bat_priv,
1935						 head, &idx, &sub))
1936			break;
1937
1938		bucket++;
1939	}
1940
1941	ret = msg->len;
1942
1943 out:
1944	batadv_hardif_put(primary_if);
1945	dev_put(mesh_iface);
1946
1947	cb->args[0] = bucket;
1948	cb->args[1] = idx;
1949	cb->args[2] = sub;
1950
1951	return ret;
1952}
1953
1954/**
1955 * _batadv_tt_global_del_orig_entry() - remove and free an orig_entry
1956 * @tt_global_entry: the global entry to remove the orig_entry from
1957 * @orig_entry: the orig entry to remove and free
1958 *
1959 * Remove an orig_entry from its list in the given tt_global_entry and
1960 * free this orig_entry afterwards.
1961 *
1962 * Caller must hold tt_global_entry->list_lock and ensure orig_entry->list is
1963 * part of a list.
1964 */
1965static void
1966_batadv_tt_global_del_orig_entry(struct batadv_tt_global_entry *tt_global_entry,
1967				 struct batadv_tt_orig_list_entry *orig_entry)
1968{
1969	lockdep_assert_held(&tt_global_entry->list_lock);
1970
1971	batadv_tt_global_size_dec(orig_entry->orig_node,
1972				  tt_global_entry->common.vid);
1973	atomic_dec(&tt_global_entry->orig_list_count);
1974	/* requires holding tt_global_entry->list_lock and orig_entry->list
1975	 * being part of a list
1976	 */
1977	hlist_del_rcu(&orig_entry->list);
1978	batadv_tt_orig_list_entry_put(orig_entry);
1979}
1980
1981/* deletes the orig list of a tt_global_entry */
1982static void
1983batadv_tt_global_del_orig_list(struct batadv_tt_global_entry *tt_global_entry)
1984{
1985	struct hlist_head *head;
1986	struct hlist_node *safe;
1987	struct batadv_tt_orig_list_entry *orig_entry;
1988
1989	spin_lock_bh(&tt_global_entry->list_lock);
1990	head = &tt_global_entry->orig_list;
1991	hlist_for_each_entry_safe(orig_entry, safe, head, list)
1992		_batadv_tt_global_del_orig_entry(tt_global_entry, orig_entry);
1993	spin_unlock_bh(&tt_global_entry->list_lock);
1994}
1995
1996/**
1997 * batadv_tt_global_del_orig_node() - remove orig_node from a global tt entry
1998 * @bat_priv: the bat priv with all the mesh interface information
1999 * @tt_global_entry: the global entry to remove the orig_node from
2000 * @orig_node: the originator announcing the client
2001 * @message: message to append to the log on deletion
2002 *
2003 * Remove the given orig_node and its according orig_entry from the given
2004 * global tt entry.
2005 */
2006static void
2007batadv_tt_global_del_orig_node(struct batadv_priv *bat_priv,
2008			       struct batadv_tt_global_entry *tt_global_entry,
2009			       struct batadv_orig_node *orig_node,
2010			       const char *message)
2011{
2012	struct hlist_head *head;
2013	struct hlist_node *safe;
2014	struct batadv_tt_orig_list_entry *orig_entry;
2015	unsigned short vid;
2016
2017	spin_lock_bh(&tt_global_entry->list_lock);
2018	head = &tt_global_entry->orig_list;
2019	hlist_for_each_entry_safe(orig_entry, safe, head, list) {
2020		if (orig_entry->orig_node == orig_node) {
2021			vid = tt_global_entry->common.vid;
2022			batadv_dbg(BATADV_DBG_TT, bat_priv,
2023				   "Deleting %pM from global tt entry %pM (vid: %d): %s\n",
2024				   orig_node->orig,
2025				   tt_global_entry->common.addr,
2026				   batadv_print_vid(vid), message);
2027			_batadv_tt_global_del_orig_entry(tt_global_entry,
2028							 orig_entry);
2029		}
2030	}
2031	spin_unlock_bh(&tt_global_entry->list_lock);
2032}
2033
2034/* If the client is to be deleted, we check if it is the last origantor entry
2035 * within tt_global entry. If yes, we set the BATADV_TT_CLIENT_ROAM flag and the
2036 * timer, otherwise we simply remove the originator scheduled for deletion.
2037 */
2038static void
2039batadv_tt_global_del_roaming(struct batadv_priv *bat_priv,
2040			     struct batadv_tt_global_entry *tt_global_entry,
2041			     struct batadv_orig_node *orig_node,
2042			     const char *message)
2043{
2044	bool last_entry = true;
2045	struct hlist_head *head;
2046	struct batadv_tt_orig_list_entry *orig_entry;
2047
2048	/* no local entry exists, case 1:
2049	 * Check if this is the last one or if other entries exist.
2050	 */
2051
2052	rcu_read_lock();
2053	head = &tt_global_entry->orig_list;
2054	hlist_for_each_entry_rcu(orig_entry, head, list) {
2055		if (orig_entry->orig_node != orig_node) {
2056			last_entry = false;
2057			break;
2058		}
2059	}
2060	rcu_read_unlock();
2061
2062	if (last_entry) {
2063		/* its the last one, mark for roaming. */
2064		tt_global_entry->common.flags |= BATADV_TT_CLIENT_ROAM;
2065		tt_global_entry->roam_at = jiffies;
2066	} else {
2067		/* there is another entry, we can simply delete this
2068		 * one and can still use the other one.
2069		 */
2070		batadv_tt_global_del_orig_node(bat_priv, tt_global_entry,
2071					       orig_node, message);
2072	}
2073}
2074
2075/**
2076 * batadv_tt_global_del() - remove a client from the global table
2077 * @bat_priv: the bat priv with all the mesh interface information
2078 * @orig_node: an originator serving this client
2079 * @addr: the mac address of the client
2080 * @vid: VLAN identifier
2081 * @message: a message explaining the reason for deleting the client to print
2082 *  for debugging purpose
2083 * @roaming: true if the deletion has been triggered by a roaming event
2084 */
2085static void batadv_tt_global_del(struct batadv_priv *bat_priv,
2086				 struct batadv_orig_node *orig_node,
2087				 const unsigned char *addr, unsigned short vid,
2088				 const char *message, bool roaming)
2089{
2090	struct batadv_tt_global_entry *tt_global_entry;
2091	struct batadv_tt_local_entry *local_entry = NULL;
2092
2093	tt_global_entry = batadv_tt_global_hash_find(bat_priv, addr, vid);
2094	if (!tt_global_entry)
2095		goto out;
2096
2097	if (!roaming) {
2098		batadv_tt_global_del_orig_node(bat_priv, tt_global_entry,
2099					       orig_node, message);
2100
2101		if (hlist_empty(&tt_global_entry->orig_list))
2102			batadv_tt_global_free(bat_priv, tt_global_entry,
2103					      message);
2104
2105		goto out;
2106	}
2107
2108	/* if we are deleting a global entry due to a roam
2109	 * event, there are two possibilities:
2110	 * 1) the client roamed from node A to node B => if there
2111	 *    is only one originator left for this client, we mark
2112	 *    it with BATADV_TT_CLIENT_ROAM, we start a timer and we
2113	 *    wait for node B to claim it. In case of timeout
2114	 *    the entry is purged.
2115	 *
2116	 *    If there are other originators left, we directly delete
2117	 *    the originator.
2118	 * 2) the client roamed to us => we can directly delete
2119	 *    the global entry, since it is useless now.
2120	 */
2121	local_entry = batadv_tt_local_hash_find(bat_priv,
2122						tt_global_entry->common.addr,
2123						vid);
2124	if (local_entry) {
2125		/* local entry exists, case 2: client roamed to us. */
2126		batadv_tt_global_del_orig_list(tt_global_entry);
2127		batadv_tt_global_free(bat_priv, tt_global_entry, message);
2128	} else {
2129		/* no local entry exists, case 1: check for roaming */
2130		batadv_tt_global_del_roaming(bat_priv, tt_global_entry,
2131					     orig_node, message);
2132	}
2133
2134out:
2135	batadv_tt_global_entry_put(tt_global_entry);
2136	batadv_tt_local_entry_put(local_entry);
2137}
2138
2139/**
2140 * batadv_tt_global_del_orig() - remove all the TT global entries belonging to
2141 *  the given originator matching the provided vid
2142 * @bat_priv: the bat priv with all the mesh interface information
2143 * @orig_node: the originator owning the entries to remove
2144 * @match_vid: the VLAN identifier to match. If negative all the entries will be
2145 *  removed
2146 * @message: debug message to print as "reason"
2147 */
2148void batadv_tt_global_del_orig(struct batadv_priv *bat_priv,
2149			       struct batadv_orig_node *orig_node,
2150			       s32 match_vid,
2151			       const char *message)
2152{
2153	struct batadv_tt_global_entry *tt_global;
2154	struct batadv_tt_common_entry *tt_common_entry;
2155	u32 i;
2156	struct batadv_hashtable *hash = bat_priv->tt.global_hash;
2157	struct hlist_node *safe;
2158	struct hlist_head *head;
2159	spinlock_t *list_lock; /* protects write access to the hash lists */
2160	unsigned short vid;
2161
2162	if (!hash)
2163		return;
2164
2165	for (i = 0; i < hash->size; i++) {
2166		head = &hash->table[i];
2167		list_lock = &hash->list_locks[i];
2168
2169		spin_lock_bh(list_lock);
2170		hlist_for_each_entry_safe(tt_common_entry, safe,
2171					  head, hash_entry) {
2172			/* remove only matching entries */
2173			if (match_vid >= 0 && tt_common_entry->vid != match_vid)
2174				continue;
2175
2176			tt_global = container_of(tt_common_entry,
2177						 struct batadv_tt_global_entry,
2178						 common);
2179
2180			batadv_tt_global_del_orig_node(bat_priv, tt_global,
2181						       orig_node, message);
2182
2183			if (hlist_empty(&tt_global->orig_list)) {
2184				vid = tt_global->common.vid;
2185				batadv_dbg(BATADV_DBG_TT, bat_priv,
2186					   "Deleting global tt entry %pM (vid: %d): %s\n",
2187					   tt_global->common.addr,
2188					   batadv_print_vid(vid), message);
2189				hlist_del_rcu(&tt_common_entry->hash_entry);
2190				batadv_tt_global_entry_put(tt_global);
2191			}
2192		}
2193		spin_unlock_bh(list_lock);
2194	}
2195	clear_bit(BATADV_ORIG_CAPA_HAS_TT, &orig_node->capa_initialized);
2196}
2197
2198static bool batadv_tt_global_to_purge(struct batadv_tt_global_entry *tt_global,
2199				      char **msg)
2200{
2201	bool purge = false;
2202	unsigned long roam_timeout = BATADV_TT_CLIENT_ROAM_TIMEOUT;
2203	unsigned long temp_timeout = BATADV_TT_CLIENT_TEMP_TIMEOUT;
2204
2205	if ((tt_global->common.flags & BATADV_TT_CLIENT_ROAM) &&
2206	    batadv_has_timed_out(tt_global->roam_at, roam_timeout)) {
2207		purge = true;
2208		*msg = "Roaming timeout\n";
2209	}
2210
2211	if ((tt_global->common.flags & BATADV_TT_CLIENT_TEMP) &&
2212	    batadv_has_timed_out(tt_global->common.added_at, temp_timeout)) {
2213		purge = true;
2214		*msg = "Temporary client timeout\n";
2215	}
2216
2217	return purge;
2218}
2219
2220static void batadv_tt_global_purge(struct batadv_priv *bat_priv)
2221{
2222	struct batadv_hashtable *hash = bat_priv->tt.global_hash;
2223	struct hlist_head *head;
2224	struct hlist_node *node_tmp;
2225	spinlock_t *list_lock; /* protects write access to the hash lists */
2226	u32 i;
2227	char *msg = NULL;
2228	struct batadv_tt_common_entry *tt_common;
2229	struct batadv_tt_global_entry *tt_global;
2230
2231	for (i = 0; i < hash->size; i++) {
2232		head = &hash->table[i];
2233		list_lock = &hash->list_locks[i];
2234
2235		spin_lock_bh(list_lock);
2236		hlist_for_each_entry_safe(tt_common, node_tmp, head,
2237					  hash_entry) {
2238			tt_global = container_of(tt_common,
2239						 struct batadv_tt_global_entry,
2240						 common);
2241
2242			if (!batadv_tt_global_to_purge(tt_global, &msg))
2243				continue;
2244
2245			batadv_dbg(BATADV_DBG_TT, bat_priv,
2246				   "Deleting global tt entry %pM (vid: %d): %s\n",
2247				   tt_global->common.addr,
2248				   batadv_print_vid(tt_global->common.vid),
2249				   msg);
2250
2251			hlist_del_rcu(&tt_common->hash_entry);
2252
2253			batadv_tt_global_entry_put(tt_global);
2254		}
2255		spin_unlock_bh(list_lock);
2256	}
2257}
2258
2259static void batadv_tt_global_table_free(struct batadv_priv *bat_priv)
2260{
2261	struct batadv_hashtable *hash;
2262	spinlock_t *list_lock; /* protects write access to the hash lists */
2263	struct batadv_tt_common_entry *tt_common_entry;
2264	struct batadv_tt_global_entry *tt_global;
2265	struct hlist_node *node_tmp;
2266	struct hlist_head *head;
2267	u32 i;
2268
2269	if (!bat_priv->tt.global_hash)
2270		return;
2271
2272	hash = bat_priv->tt.global_hash;
2273
2274	for (i = 0; i < hash->size; i++) {
2275		head = &hash->table[i];
2276		list_lock = &hash->list_locks[i];
2277
2278		spin_lock_bh(list_lock);
2279		hlist_for_each_entry_safe(tt_common_entry, node_tmp,
2280					  head, hash_entry) {
2281			hlist_del_rcu(&tt_common_entry->hash_entry);
2282			tt_global = container_of(tt_common_entry,
2283						 struct batadv_tt_global_entry,
2284						 common);
2285			batadv_tt_global_entry_put(tt_global);
2286		}
2287		spin_unlock_bh(list_lock);
2288	}
2289
2290	batadv_hash_destroy(hash);
2291
2292	bat_priv->tt.global_hash = NULL;
2293}
2294
2295static bool
2296_batadv_is_ap_isolated(struct batadv_tt_local_entry *tt_local_entry,
2297		       struct batadv_tt_global_entry *tt_global_entry)
2298{
2299	if (tt_local_entry->common.flags & BATADV_TT_CLIENT_WIFI &&
2300	    tt_global_entry->common.flags & BATADV_TT_CLIENT_WIFI)
2301		return true;
2302
2303	/* check if the two clients are marked as isolated */
2304	if (tt_local_entry->common.flags & BATADV_TT_CLIENT_ISOLA &&
2305	    tt_global_entry->common.flags & BATADV_TT_CLIENT_ISOLA)
2306		return true;
2307
2308	return false;
2309}
2310
2311/**
2312 * batadv_transtable_search() - get the mesh destination for a given client
2313 * @bat_priv: the bat priv with all the mesh interface information
2314 * @src: mac address of the source client
2315 * @addr: mac address of the destination client
2316 * @vid: VLAN identifier
2317 *
2318 * Return: a pointer to the originator that was selected as destination in the
2319 * mesh for contacting the client 'addr', NULL otherwise.
2320 * In case of multiple originators serving the same client, the function returns
2321 * the best one (best in terms of metric towards the destination node).
2322 *
2323 * If the two clients are AP isolated the function returns NULL.
2324 */
2325struct batadv_orig_node *batadv_transtable_search(struct batadv_priv *bat_priv,
2326						  const u8 *src,
2327						  const u8 *addr,
2328						  unsigned short vid)
2329{
2330	struct batadv_tt_local_entry *tt_local_entry = NULL;
2331	struct batadv_tt_global_entry *tt_global_entry = NULL;
2332	struct batadv_orig_node *orig_node = NULL;
2333	struct batadv_tt_orig_list_entry *best_entry;
2334
2335	if (src && batadv_vlan_ap_isola_get(bat_priv, vid)) {
2336		tt_local_entry = batadv_tt_local_hash_find(bat_priv, src, vid);
2337		if (!tt_local_entry ||
2338		    (tt_local_entry->common.flags & BATADV_TT_CLIENT_PENDING))
2339			goto out;
2340	}
2341
2342	tt_global_entry = batadv_tt_global_hash_find(bat_priv, addr, vid);
2343	if (!tt_global_entry)
2344		goto out;
2345
2346	/* check whether the clients should not communicate due to AP
2347	 * isolation
2348	 */
2349	if (tt_local_entry &&
2350	    _batadv_is_ap_isolated(tt_local_entry, tt_global_entry))
2351		goto out;
2352
2353	rcu_read_lock();
2354	best_entry = batadv_transtable_best_orig(bat_priv, tt_global_entry);
2355	/* found anything? */
2356	if (best_entry)
2357		orig_node = best_entry->orig_node;
2358	if (orig_node && !kref_get_unless_zero(&orig_node->refcount))
2359		orig_node = NULL;
2360	rcu_read_unlock();
2361
2362out:
2363	batadv_tt_global_entry_put(tt_global_entry);
2364	batadv_tt_local_entry_put(tt_local_entry);
2365
2366	return orig_node;
2367}
2368
2369/**
2370 * batadv_tt_global_crc() - calculates the checksum of the local table belonging
2371 *  to the given orig_node
2372 * @bat_priv: the bat priv with all the mesh interface information
2373 * @orig_node: originator for which the CRC should be computed
2374 * @vid: VLAN identifier for which the CRC32 has to be computed
2375 *
2376 * This function computes the checksum for the global table corresponding to a
2377 * specific originator. In particular, the checksum is computed as follows: For
2378 * each client connected to the originator the CRC32C of the MAC address and the
2379 * VID is computed and then all the CRC32Cs of the various clients are xor'ed
2380 * together.
2381 *
2382 * The idea behind is that CRC32C should be used as much as possible in order to
2383 * produce a unique hash of the table, but since the order which is used to feed
2384 * the CRC32C function affects the result and since every node in the network
2385 * probably sorts the clients differently, the hash function cannot be directly
2386 * computed over the entire table. Hence the CRC32C is used only on
2387 * the single client entry, while all the results are then xor'ed together
2388 * because the XOR operation can combine them all while trying to reduce the
2389 * noise as much as possible.
2390 *
2391 * Return: the checksum of the global table of a given originator.
2392 */
2393static u32 batadv_tt_global_crc(struct batadv_priv *bat_priv,
2394				struct batadv_orig_node *orig_node,
2395				unsigned short vid)
2396{
2397	struct batadv_hashtable *hash = bat_priv->tt.global_hash;
2398	struct batadv_tt_orig_list_entry *tt_orig;
2399	struct batadv_tt_common_entry *tt_common;
2400	struct batadv_tt_global_entry *tt_global;
2401	struct hlist_head *head;
2402	u32 i, crc_tmp, crc = 0;
2403	u8 flags;
2404	__be16 tmp_vid;
2405
2406	for (i = 0; i < hash->size; i++) {
2407		head = &hash->table[i];
2408
2409		rcu_read_lock();
2410		hlist_for_each_entry_rcu(tt_common, head, hash_entry) {
2411			tt_global = container_of(tt_common,
2412						 struct batadv_tt_global_entry,
2413						 common);
2414			/* compute the CRC only for entries belonging to the
2415			 * VLAN identified by the vid passed as parameter
2416			 */
2417			if (tt_common->vid != vid)
2418				continue;
2419
2420			/* Roaming clients are in the global table for
2421			 * consistency only. They don't have to be
2422			 * taken into account while computing the
2423			 * global crc
2424			 */
2425			if (tt_common->flags & BATADV_TT_CLIENT_ROAM)
2426				continue;
2427			/* Temporary clients have not been announced yet, so
2428			 * they have to be skipped while computing the global
2429			 * crc
2430			 */
2431			if (tt_common->flags & BATADV_TT_CLIENT_TEMP)
2432				continue;
2433
2434			/* find out if this global entry is announced by this
2435			 * originator
2436			 */
2437			tt_orig = batadv_tt_global_orig_entry_find(tt_global,
2438								   orig_node);
2439			if (!tt_orig)
2440				continue;
2441
2442			/* use network order to read the VID: this ensures that
2443			 * every node reads the bytes in the same order.
2444			 */
2445			tmp_vid = htons(tt_common->vid);
2446			crc_tmp = crc32c(0, &tmp_vid, sizeof(tmp_vid));
2447
2448			/* compute the CRC on flags that have to be kept in sync
2449			 * among nodes
2450			 */
2451			flags = tt_orig->flags;
2452			crc_tmp = crc32c(crc_tmp, &flags, sizeof(flags));
2453
2454			crc ^= crc32c(crc_tmp, tt_common->addr, ETH_ALEN);
2455
2456			batadv_tt_orig_list_entry_put(tt_orig);
2457		}
2458		rcu_read_unlock();
2459	}
2460
2461	return crc;
2462}
2463
2464/**
2465 * batadv_tt_local_crc() - calculates the checksum of the local table
2466 * @bat_priv: the bat priv with all the mesh interface information
2467 * @vid: VLAN identifier for which the CRC32 has to be computed
2468 *
2469 * For details about the computation, please refer to the documentation for
2470 * batadv_tt_global_crc().
2471 *
2472 * Return: the checksum of the local table
2473 */
2474static u32 batadv_tt_local_crc(struct batadv_priv *bat_priv,
2475			       unsigned short vid)
2476{
2477	struct batadv_hashtable *hash = bat_priv->tt.local_hash;
2478	struct batadv_tt_common_entry *tt_common;
2479	struct hlist_head *head;
2480	u32 i, crc_tmp, crc = 0;
2481	u8 flags;
2482	__be16 tmp_vid;
2483
2484	for (i = 0; i < hash->size; i++) {
2485		head = &hash->table[i];
2486
2487		rcu_read_lock();
2488		hlist_for_each_entry_rcu(tt_common, head, hash_entry) {
2489			/* compute the CRC only for entries belonging to the
2490			 * VLAN identified by vid
2491			 */
2492			if (tt_common->vid != vid)
2493				continue;
2494
2495			/* not yet committed clients have not to be taken into
2496			 * account while computing the CRC
2497			 */
2498			if (tt_common->flags & BATADV_TT_CLIENT_NEW)
2499				continue;
2500
2501			/* use network order to read the VID: this ensures that
2502			 * every node reads the bytes in the same order.
2503			 */
2504			tmp_vid = htons(tt_common->vid);
2505			crc_tmp = crc32c(0, &tmp_vid, sizeof(tmp_vid));
2506
2507			/* compute the CRC on flags that have to be kept in sync
2508			 * among nodes
2509			 */
2510			flags = tt_common->flags & BATADV_TT_SYNC_MASK;
2511			crc_tmp = crc32c(crc_tmp, &flags, sizeof(flags));
2512
2513			crc ^= crc32c(crc_tmp, tt_common->addr, ETH_ALEN);
2514		}
2515		rcu_read_unlock();
2516	}
2517
2518	return crc;
2519}
2520
2521/**
2522 * batadv_tt_req_node_release() - free tt_req node entry
2523 * @ref: kref pointer of the tt req_node entry
2524 */
2525static void batadv_tt_req_node_release(struct kref *ref)
2526{
2527	struct batadv_tt_req_node *tt_req_node;
2528
2529	tt_req_node = container_of(ref, struct batadv_tt_req_node, refcount);
2530
2531	kmem_cache_free(batadv_tt_req_cache, tt_req_node);
2532}
2533
2534/**
2535 * batadv_tt_req_node_put() - decrement the tt_req_node refcounter and
2536 *  possibly release it
2537 * @tt_req_node: tt_req_node to be free'd
2538 */
2539static void batadv_tt_req_node_put(struct batadv_tt_req_node *tt_req_node)
2540{
2541	if (!tt_req_node)
2542		return;
2543
2544	kref_put(&tt_req_node->refcount, batadv_tt_req_node_release);
2545}
2546
2547static void batadv_tt_req_list_free(struct batadv_priv *bat_priv)
2548{
2549	struct batadv_tt_req_node *node;
2550	struct hlist_node *safe;
2551
2552	spin_lock_bh(&bat_priv->tt.req_list_lock);
2553
2554	hlist_for_each_entry_safe(node, safe, &bat_priv->tt.req_list, list) {
2555		hlist_del_init(&node->list);
2556		batadv_tt_req_node_put(node);
2557	}
2558
2559	spin_unlock_bh(&bat_priv->tt.req_list_lock);
2560}
2561
2562static void batadv_tt_save_orig_buffer(struct batadv_priv *bat_priv,
2563				       struct batadv_orig_node *orig_node,
2564				       const void *tt_buff,
2565				       u16 tt_buff_len)
2566{
2567	/* Replace the old buffer only if I received something in the
2568	 * last OGM (the OGM could carry no changes)
2569	 */
2570	spin_lock_bh(&orig_node->tt_buff_lock);
2571	if (tt_buff_len > 0) {
2572		kfree(orig_node->tt_buff);
2573		orig_node->tt_buff_len = 0;
2574		orig_node->tt_buff = kmalloc(tt_buff_len, GFP_ATOMIC);
2575		if (orig_node->tt_buff) {
2576			memcpy(orig_node->tt_buff, tt_buff, tt_buff_len);
2577			orig_node->tt_buff_len = tt_buff_len;
2578		}
2579	}
2580	spin_unlock_bh(&orig_node->tt_buff_lock);
2581}
2582
2583static void batadv_tt_req_purge(struct batadv_priv *bat_priv)
2584{
2585	struct batadv_tt_req_node *node;
2586	struct hlist_node *safe;
2587
2588	spin_lock_bh(&bat_priv->tt.req_list_lock);
2589	hlist_for_each_entry_safe(node, safe, &bat_priv->tt.req_list, list) {
2590		if (batadv_has_timed_out(node->issued_at,
2591					 BATADV_TT_REQUEST_TIMEOUT)) {
2592			hlist_del_init(&node->list);
2593			batadv_tt_req_node_put(node);
2594		}
2595	}
2596	spin_unlock_bh(&bat_priv->tt.req_list_lock);
2597}
2598
2599/**
2600 * batadv_tt_req_node_new() - search and possibly create a tt_req_node object
2601 * @bat_priv: the bat priv with all the mesh interface information
2602 * @orig_node: orig node this request is being issued for
2603 *
2604 * Return: the pointer to the new tt_req_node struct if no request
2605 * has already been issued for this orig_node, NULL otherwise.
2606 */
2607static struct batadv_tt_req_node *
2608batadv_tt_req_node_new(struct batadv_priv *bat_priv,
2609		       struct batadv_orig_node *orig_node)
2610{
2611	struct batadv_tt_req_node *tt_req_node_tmp, *tt_req_node = NULL;
2612
2613	spin_lock_bh(&bat_priv->tt.req_list_lock);
2614	hlist_for_each_entry(tt_req_node_tmp, &bat_priv->tt.req_list, list) {
2615		if (batadv_compare_eth(tt_req_node_tmp, orig_node) &&
2616		    !batadv_has_timed_out(tt_req_node_tmp->issued_at,
2617					  BATADV_TT_REQUEST_TIMEOUT))
2618			goto unlock;
2619	}
2620
2621	tt_req_node = kmem_cache_alloc(batadv_tt_req_cache, GFP_ATOMIC);
2622	if (!tt_req_node)
2623		goto unlock;
2624
2625	kref_init(&tt_req_node->refcount);
2626	ether_addr_copy(tt_req_node->addr, orig_node->orig);
2627	tt_req_node->issued_at = jiffies;
2628
2629	kref_get(&tt_req_node->refcount);
2630	hlist_add_head(&tt_req_node->list, &bat_priv->tt.req_list);
2631unlock:
2632	spin_unlock_bh(&bat_priv->tt.req_list_lock);
2633	return tt_req_node;
2634}
2635
2636/**
2637 * batadv_tt_local_valid() - verify local tt entry and get flags
2638 * @entry_ptr: to be checked local tt entry
2639 * @data_ptr: not used but definition required to satisfy the callback prototype
2640 * @flags: a pointer to store TT flags for this client to
2641 *
2642 * Checks the validity of the given local TT entry. If it is, then the provided
2643 * flags pointer is updated.
2644 *
2645 * Return: true if the entry is a valid, false otherwise.
2646 */
2647static bool batadv_tt_local_valid(const void *entry_ptr,
2648				  const void *data_ptr,
2649				  u8 *flags)
2650{
2651	const struct batadv_tt_common_entry *tt_common_entry = entry_ptr;
2652
2653	if (tt_common_entry->flags & BATADV_TT_CLIENT_NEW)
2654		return false;
2655
2656	if (flags)
2657		*flags = tt_common_entry->flags;
2658
2659	return true;
2660}
2661
2662/**
2663 * batadv_tt_global_valid() - verify global tt entry and get flags
2664 * @entry_ptr: to be checked global tt entry
2665 * @data_ptr: an orig_node object (may be NULL)
2666 * @flags: a pointer to store TT flags for this client to
2667 *
2668 * Checks the validity of the given global TT entry. If it is, then the provided
2669 * flags pointer is updated either with the common (summed) TT flags if data_ptr
2670 * is NULL or the specific, per originator TT flags otherwise.
2671 *
2672 * Return: true if the entry is a valid, false otherwise.
2673 */
2674static bool batadv_tt_global_valid(const void *entry_ptr,
2675				   const void *data_ptr,
2676				   u8 *flags)
2677{
2678	const struct batadv_tt_common_entry *tt_common_entry = entry_ptr;
2679	const struct batadv_tt_global_entry *tt_global_entry;
2680	const struct batadv_orig_node *orig_node = data_ptr;
2681
2682	if (tt_common_entry->flags & BATADV_TT_CLIENT_ROAM ||
2683	    tt_common_entry->flags & BATADV_TT_CLIENT_TEMP)
2684		return false;
2685
2686	tt_global_entry = container_of(tt_common_entry,
2687				       struct batadv_tt_global_entry,
2688				       common);
2689
2690	return batadv_tt_global_entry_has_orig(tt_global_entry, orig_node,
2691					       flags);
2692}
2693
2694/**
2695 * batadv_tt_tvlv_generate() - fill the tvlv buff with the tt entries from the
2696 *  specified tt hash
2697 * @bat_priv: the bat priv with all the mesh interface information
2698 * @hash: hash table containing the tt entries
2699 * @tt_len: expected tvlv tt data buffer length in number of bytes
2700 * @tvlv_buff: pointer to the buffer to fill with the TT data
2701 * @valid_cb: function to filter tt change entries and to return TT flags
2702 * @cb_data: data passed to the filter function as argument
2703 *
2704 * Fills the tvlv buff with the tt entries from the specified hash. If valid_cb
2705 * is not provided then this becomes a no-op.
2706 *
2707 * Return: Remaining unused length in tvlv_buff.
2708 */
2709static u16 batadv_tt_tvlv_generate(struct batadv_priv *bat_priv,
2710				   struct batadv_hashtable *hash,
2711				   void *tvlv_buff, u16 tt_len,
2712				   bool (*valid_cb)(const void *,
2713						    const void *,
2714						    u8 *flags),
2715				   void *cb_data)
2716{
2717	struct batadv_tt_common_entry *tt_common_entry;
2718	struct batadv_tvlv_tt_change *tt_change;
2719	struct hlist_head *head;
2720	u16 tt_tot, tt_num_entries = 0;
2721	u8 flags;
2722	bool ret;
2723	u32 i;
2724
2725	tt_tot = batadv_tt_entries(tt_len);
2726	tt_change = tvlv_buff;
2727
2728	if (!valid_cb)
2729		return tt_len;
2730
2731	rcu_read_lock();
2732	for (i = 0; i < hash->size; i++) {
2733		head = &hash->table[i];
2734
2735		hlist_for_each_entry_rcu(tt_common_entry,
2736					 head, hash_entry) {
2737			if (tt_tot == tt_num_entries)
2738				break;
2739
2740			ret = valid_cb(tt_common_entry, cb_data, &flags);
2741			if (!ret)
2742				continue;
2743
2744			ether_addr_copy(tt_change->addr, tt_common_entry->addr);
2745			tt_change->flags = flags;
2746			tt_change->vid = htons(tt_common_entry->vid);
2747			memset(tt_change->reserved, 0,
2748			       sizeof(tt_change->reserved));
2749
2750			tt_num_entries++;
2751			tt_change++;
2752		}
2753	}
2754	rcu_read_unlock();
2755
2756	return batadv_tt_len(tt_tot - tt_num_entries);
2757}
2758
2759/**
2760 * batadv_tt_global_check_crc() - check if all the CRCs are correct
2761 * @orig_node: originator for which the CRCs have to be checked
2762 * @tt_vlan: pointer to the first tvlv VLAN entry
2763 * @num_vlan: number of tvlv VLAN entries
2764 *
2765 * Return: true if all the received CRCs match the locally stored ones, false
2766 * otherwise
2767 */
2768static bool batadv_tt_global_check_crc(struct batadv_orig_node *orig_node,
2769				       struct batadv_tvlv_tt_vlan_data *tt_vlan,
2770				       u16 num_vlan)
2771{
2772	struct batadv_tvlv_tt_vlan_data *tt_vlan_tmp;
2773	struct batadv_orig_node_vlan *vlan;
2774	int i, orig_num_vlan;
2775	u32 crc;
2776
2777	/* check if each received CRC matches the locally stored one */
2778	for (i = 0; i < num_vlan; i++) {
2779		tt_vlan_tmp = tt_vlan + i;
2780
2781		/* if orig_node is a backbone node for this VLAN, don't check
2782		 * the CRC as we ignore all the global entries over it
2783		 */
2784		if (batadv_bla_is_backbone_gw_orig(orig_node->bat_priv,
2785						   orig_node->orig,
2786						   ntohs(tt_vlan_tmp->vid)))
2787			continue;
2788
2789		vlan = batadv_orig_node_vlan_get(orig_node,
2790						 ntohs(tt_vlan_tmp->vid));
2791		if (!vlan)
2792			return false;
2793
2794		crc = vlan->tt.crc;
2795		batadv_orig_node_vlan_put(vlan);
2796
2797		if (crc != ntohl(tt_vlan_tmp->crc))
2798			return false;
2799	}
2800
2801	/* check if any excess VLANs exist locally for the originator
2802	 * which are not mentioned in the TVLV from the originator.
2803	 */
2804	rcu_read_lock();
2805	orig_num_vlan = 0;
2806	hlist_for_each_entry_rcu(vlan, &orig_node->vlan_list, list)
2807		orig_num_vlan++;
2808	rcu_read_unlock();
2809
2810	if (orig_num_vlan > num_vlan)
2811		return false;
2812
2813	return true;
2814}
2815
2816/**
2817 * batadv_tt_local_update_crc() - update all the local CRCs
2818 * @bat_priv: the bat priv with all the mesh interface information
2819 */
2820static void batadv_tt_local_update_crc(struct batadv_priv *bat_priv)
2821{
2822	struct batadv_meshif_vlan *vlan;
2823
2824	/* recompute the global CRC for each VLAN */
2825	rcu_read_lock();
2826	hlist_for_each_entry_rcu(vlan, &bat_priv->meshif_vlan_list, list) {
2827		vlan->tt.crc = batadv_tt_local_crc(bat_priv, vlan->vid);
2828	}
2829	rcu_read_unlock();
2830}
2831
2832/**
2833 * batadv_tt_global_update_crc() - update all the global CRCs for this orig_node
2834 * @bat_priv: the bat priv with all the mesh interface information
2835 * @orig_node: the orig_node for which the CRCs have to be updated
2836 */
2837static void batadv_tt_global_update_crc(struct batadv_priv *bat_priv,
2838					struct batadv_orig_node *orig_node)
2839{
2840	struct batadv_orig_node_vlan *vlan;
2841	u32 crc;
2842
2843	/* recompute the global CRC for each VLAN */
2844	rcu_read_lock();
2845	hlist_for_each_entry_rcu(vlan, &orig_node->vlan_list, list) {
2846		/* if orig_node is a backbone node for this VLAN, don't compute
2847		 * the CRC as we ignore all the global entries over it
2848		 */
2849		if (batadv_bla_is_backbone_gw_orig(bat_priv, orig_node->orig,
2850						   vlan->vid))
2851			continue;
2852
2853		crc = batadv_tt_global_crc(bat_priv, orig_node, vlan->vid);
2854		vlan->tt.crc = crc;
2855	}
2856	rcu_read_unlock();
2857}
2858
2859/**
2860 * batadv_send_tt_request() - send a TT Request message to a given node
2861 * @bat_priv: the bat priv with all the mesh interface information
2862 * @dst_orig_node: the destination of the message
2863 * @ttvn: the version number that the source of the message is looking for
2864 * @tt_vlan: pointer to the first tvlv VLAN object to request
2865 * @num_vlan: number of tvlv VLAN entries
2866 * @full_table: ask for the entire translation table if true, while only for the
2867 *  last TT diff otherwise
2868 *
2869 * Return: true if the TT Request was sent, false otherwise
2870 */
2871static bool batadv_send_tt_request(struct batadv_priv *bat_priv,
2872				   struct batadv_orig_node *dst_orig_node,
2873				   u8 ttvn,
2874				   struct batadv_tvlv_tt_vlan_data *tt_vlan,
2875				   u16 num_vlan, bool full_table)
2876{
2877	struct batadv_tvlv_tt_data *tvlv_tt_data = NULL;
2878	struct batadv_tt_req_node *tt_req_node = NULL;
2879	struct batadv_hard_iface *primary_if;
2880	bool ret = false;
2881	int i, size;
2882
2883	primary_if = batadv_primary_if_get_selected(bat_priv);
2884	if (!primary_if)
2885		goto out;
2886
2887	/* The new tt_req will be issued only if I'm not waiting for a
2888	 * reply from the same orig_node yet
2889	 */
2890	tt_req_node = batadv_tt_req_node_new(bat_priv, dst_orig_node);
2891	if (!tt_req_node)
2892		goto out;
2893
2894	size = struct_size(tvlv_tt_data, vlan_data, num_vlan);
2895	tvlv_tt_data = kzalloc(size, GFP_ATOMIC);
2896	if (!tvlv_tt_data)
2897		goto out;
2898
2899	tvlv_tt_data->flags = BATADV_TT_REQUEST;
2900	tvlv_tt_data->ttvn = ttvn;
2901	tvlv_tt_data->num_vlan = htons(num_vlan);
2902
2903	/* send all the CRCs within the request. This is needed by intermediate
2904	 * nodes to ensure they have the correct table before replying
2905	 */
2906	for (i = 0; i < num_vlan; i++) {
2907		tvlv_tt_data->vlan_data[i].vid = tt_vlan->vid;
2908		tvlv_tt_data->vlan_data[i].crc = tt_vlan->crc;
2909
2910		tt_vlan++;
2911	}
2912
2913	if (full_table)
2914		tvlv_tt_data->flags |= BATADV_TT_FULL_TABLE;
2915
2916	batadv_dbg(BATADV_DBG_TT, bat_priv, "Sending TT_REQUEST to %pM [%c]\n",
2917		   dst_orig_node->orig, full_table ? 'F' : '.');
2918
2919	batadv_inc_counter(bat_priv, BATADV_CNT_TT_REQUEST_TX);
2920	batadv_tvlv_unicast_send(bat_priv, primary_if->net_dev->dev_addr,
2921				 dst_orig_node->orig, BATADV_TVLV_TT, 1,
2922				 tvlv_tt_data, size);
2923	ret = true;
2924
2925out:
2926	batadv_hardif_put(primary_if);
2927
2928	if (ret && tt_req_node) {
2929		spin_lock_bh(&bat_priv->tt.req_list_lock);
2930		if (!hlist_unhashed(&tt_req_node->list)) {
2931			hlist_del_init(&tt_req_node->list);
2932			batadv_tt_req_node_put(tt_req_node);
2933		}
2934		spin_unlock_bh(&bat_priv->tt.req_list_lock);
2935	}
2936
2937	batadv_tt_req_node_put(tt_req_node);
2938
2939	kfree(tvlv_tt_data);
2940	return ret;
2941}
2942
2943/**
2944 * batadv_send_other_tt_response() - send reply to tt request concerning another
2945 *  node's translation table
2946 * @bat_priv: the bat priv with all the mesh interface information
2947 * @tt_data: tt data containing the tt request information
2948 * @req_src: mac address of tt request sender
2949 * @req_dst: mac address of tt request recipient
2950 *
2951 * Return: true if tt request reply was sent, false otherwise.
2952 */
2953static bool batadv_send_other_tt_response(struct batadv_priv *bat_priv,
2954					  struct batadv_tvlv_tt_data *tt_data,
2955					  u8 *req_src, u8 *req_dst)
2956{
2957	struct batadv_orig_node *req_dst_orig_node;
2958	struct batadv_orig_node *res_dst_orig_node = NULL;
2959	struct batadv_tvlv_tt_change *tt_change;
2960	struct batadv_tvlv_tt_data *tvlv_tt_data = NULL;
2961	bool ret = false, full_table;
2962	u8 orig_ttvn, req_ttvn;
2963	u16 tvlv_len;
2964	s32 tt_len;
2965
2966	batadv_dbg(BATADV_DBG_TT, bat_priv,
2967		   "Received TT_REQUEST from %pM for ttvn: %u (%pM) [%c]\n",
2968		   req_src, tt_data->ttvn, req_dst,
2969		   ((tt_data->flags & BATADV_TT_FULL_TABLE) ? 'F' : '.'));
2970
2971	/* Let's get the orig node of the REAL destination */
2972	req_dst_orig_node = batadv_orig_hash_find(bat_priv, req_dst);
2973	if (!req_dst_orig_node)
2974		goto out;
2975
2976	res_dst_orig_node = batadv_orig_hash_find(bat_priv, req_src);
2977	if (!res_dst_orig_node)
2978		goto out;
2979
2980	orig_ttvn = (u8)atomic_read(&req_dst_orig_node->last_ttvn);
2981	req_ttvn = tt_data->ttvn;
2982
2983	/* this node doesn't have the requested data */
2984	if (orig_ttvn != req_ttvn ||
2985	    !batadv_tt_global_check_crc(req_dst_orig_node, tt_data->vlan_data,
2986					ntohs(tt_data->num_vlan)))
2987		goto out;
2988
2989	/* If the full table has been explicitly requested */
2990	if (tt_data->flags & BATADV_TT_FULL_TABLE ||
2991	    !req_dst_orig_node->tt_buff)
2992		full_table = true;
2993	else
2994		full_table = false;
2995
2996	/* TT fragmentation hasn't been implemented yet, so send as many
2997	 * TT entries fit a single packet as possible only
2998	 */
2999	if (!full_table) {
3000		spin_lock_bh(&req_dst_orig_node->tt_buff_lock);
3001		tt_len = req_dst_orig_node->tt_buff_len;
3002
3003		tvlv_len = batadv_tt_prepare_tvlv_global_data(req_dst_orig_node,
3004							      &tvlv_tt_data,
3005							      &tt_change,
3006							      &tt_len);
3007		if (!tt_len)
3008			goto unlock;
3009
3010		/* Copy the last orig_node's OGM buffer */
3011		memcpy(tt_change, req_dst_orig_node->tt_buff,
3012		       req_dst_orig_node->tt_buff_len);
3013		spin_unlock_bh(&req_dst_orig_node->tt_buff_lock);
3014	} else {
3015		/* allocate the tvlv, put the tt_data and all the tt_vlan_data
3016		 * in the initial part
3017		 */
3018		tt_len = -1;
3019		tvlv_len = batadv_tt_prepare_tvlv_global_data(req_dst_orig_node,
3020							      &tvlv_tt_data,
3021							      &tt_change,
3022							      &tt_len);
3023		if (!tt_len)
3024			goto out;
3025
3026		/* fill the rest of the tvlv with the real TT entries */
3027		tvlv_len -= batadv_tt_tvlv_generate(bat_priv,
3028						    bat_priv->tt.global_hash,
3029						    tt_change, tt_len,
3030						    batadv_tt_global_valid,
3031						    req_dst_orig_node);
3032	}
3033
3034	/* Don't send the response, if larger than fragmented packet. */
3035	tt_len = sizeof(struct batadv_unicast_tvlv_packet) + tvlv_len;
3036	if (tt_len > atomic_read(&bat_priv->packet_size_max)) {
3037		net_ratelimited_function(batadv_info, bat_priv->mesh_iface,
3038					 "Ignoring TT_REQUEST from %pM; Response size exceeds max packet size.\n",
3039					 res_dst_orig_node->orig);
3040		goto out;
3041	}
3042
3043	tvlv_tt_data->flags = BATADV_TT_RESPONSE;
3044	tvlv_tt_data->ttvn = req_ttvn;
3045
3046	if (full_table)
3047		tvlv_tt_data->flags |= BATADV_TT_FULL_TABLE;
3048
3049	batadv_dbg(BATADV_DBG_TT, bat_priv,
3050		   "Sending TT_RESPONSE %pM for %pM [%c] (ttvn: %u)\n",
3051		   res_dst_orig_node->orig, req_dst_orig_node->orig,
3052		   full_table ? 'F' : '.', req_ttvn);
3053
3054	batadv_inc_counter(bat_priv, BATADV_CNT_TT_RESPONSE_TX);
3055
3056	batadv_tvlv_unicast_send(bat_priv, req_dst_orig_node->orig,
3057				 req_src, BATADV_TVLV_TT, 1, tvlv_tt_data,
3058				 tvlv_len);
3059
3060	ret = true;
3061	goto out;
3062
3063unlock:
3064	spin_unlock_bh(&req_dst_orig_node->tt_buff_lock);
3065
3066out:
3067	batadv_orig_node_put(res_dst_orig_node);
3068	batadv_orig_node_put(req_dst_orig_node);
3069	kfree(tvlv_tt_data);
3070	return ret;
3071}
3072
3073/**
3074 * batadv_send_my_tt_response() - send reply to tt request concerning this
3075 *  node's translation table
3076 * @bat_priv: the bat priv with all the mesh interface information
3077 * @tt_data: tt data containing the tt request information
3078 * @req_src: mac address of tt request sender
3079 *
3080 * Return: true if tt request reply was sent, false otherwise.
3081 */
3082static bool batadv_send_my_tt_response(struct batadv_priv *bat_priv,
3083				       struct batadv_tvlv_tt_data *tt_data,
3084				       u8 *req_src)
3085{
3086	struct batadv_tvlv_tt_data *tvlv_tt_data = NULL;
3087	struct batadv_hard_iface *primary_if = NULL;
3088	struct batadv_tvlv_tt_change *tt_change;
3089	struct batadv_orig_node *orig_node;
3090	u8 my_ttvn, req_ttvn;
3091	u16 tvlv_len;
3092	bool full_table;
3093	s32 tt_len;
3094
3095	batadv_dbg(BATADV_DBG_TT, bat_priv,
3096		   "Received TT_REQUEST from %pM for ttvn: %u (me) [%c]\n",
3097		   req_src, tt_data->ttvn,
3098		   ((tt_data->flags & BATADV_TT_FULL_TABLE) ? 'F' : '.'));
3099
3100	spin_lock_bh(&bat_priv->tt.commit_lock);
3101
3102	my_ttvn = (u8)atomic_read(&bat_priv->tt.vn);
3103	req_ttvn = tt_data->ttvn;
3104
3105	orig_node = batadv_orig_hash_find(bat_priv, req_src);
3106	if (!orig_node)
3107		goto out;
3108
3109	primary_if = batadv_primary_if_get_selected(bat_priv);
3110	if (!primary_if)
3111		goto out;
3112
3113	/* If the full table has been explicitly requested or the gap
3114	 * is too big send the whole local translation table
3115	 */
3116	if (tt_data->flags & BATADV_TT_FULL_TABLE || my_ttvn != req_ttvn ||
3117	    !bat_priv->tt.last_changeset)
3118		full_table = true;
3119	else
3120		full_table = false;
3121
3122	/* TT fragmentation hasn't been implemented yet, so send as many
3123	 * TT entries fit a single packet as possible only
3124	 */
3125	if (!full_table) {
3126		spin_lock_bh(&bat_priv->tt.last_changeset_lock);
3127
3128		tt_len = bat_priv->tt.last_changeset_len;
3129		tvlv_len = batadv_tt_prepare_tvlv_local_data(bat_priv,
3130							     &tvlv_tt_data,
3131							     &tt_change,
3132							     &tt_len);
3133		if (!tt_len || !tvlv_len)
3134			goto unlock;
3135
3136		/* Copy the last orig_node's OGM buffer */
3137		memcpy(tt_change, bat_priv->tt.last_changeset,
3138		       bat_priv->tt.last_changeset_len);
3139		spin_unlock_bh(&bat_priv->tt.last_changeset_lock);
3140	} else {
3141		req_ttvn = (u8)atomic_read(&bat_priv->tt.vn);
3142
3143		/* allocate the tvlv, put the tt_data and all the tt_vlan_data
3144		 * in the initial part
3145		 */
3146		tt_len = -1;
3147		tvlv_len = batadv_tt_prepare_tvlv_local_data(bat_priv,
3148							     &tvlv_tt_data,
3149							     &tt_change,
3150							     &tt_len);
3151		if (!tt_len || !tvlv_len)
3152			goto out;
3153
3154		/* fill the rest of the tvlv with the real TT entries */
3155		tvlv_len -= batadv_tt_tvlv_generate(bat_priv,
3156						    bat_priv->tt.local_hash,
3157						    tt_change, tt_len,
3158						    batadv_tt_local_valid,
3159						    NULL);
3160	}
3161
3162	tvlv_tt_data->flags = BATADV_TT_RESPONSE;
3163	tvlv_tt_data->ttvn = req_ttvn;
3164
3165	if (full_table)
3166		tvlv_tt_data->flags |= BATADV_TT_FULL_TABLE;
3167
3168	batadv_dbg(BATADV_DBG_TT, bat_priv,
3169		   "Sending TT_RESPONSE to %pM [%c] (ttvn: %u)\n",
3170		   orig_node->orig, full_table ? 'F' : '.', req_ttvn);
3171
3172	batadv_inc_counter(bat_priv, BATADV_CNT_TT_RESPONSE_TX);
3173
3174	batadv_tvlv_unicast_send(bat_priv, primary_if->net_dev->dev_addr,
3175				 req_src, BATADV_TVLV_TT, 1, tvlv_tt_data,
3176				 tvlv_len);
3177
3178	goto out;
3179
3180unlock:
3181	spin_unlock_bh(&bat_priv->tt.last_changeset_lock);
3182out:
3183	spin_unlock_bh(&bat_priv->tt.commit_lock);
3184	batadv_orig_node_put(orig_node);
3185	batadv_hardif_put(primary_if);
3186	kfree(tvlv_tt_data);
3187	/* The packet was for this host, so it doesn't need to be re-routed */
3188	return true;
3189}
3190
3191/**
3192 * batadv_send_tt_response() - send reply to tt request
3193 * @bat_priv: the bat priv with all the mesh interface information
3194 * @tt_data: tt data containing the tt request information
3195 * @req_src: mac address of tt request sender
3196 * @req_dst: mac address of tt request recipient
3197 *
3198 * Return: true if tt request reply was sent, false otherwise.
3199 */
3200static bool batadv_send_tt_response(struct batadv_priv *bat_priv,
3201				    struct batadv_tvlv_tt_data *tt_data,
3202				    u8 *req_src, u8 *req_dst)
3203{
3204	if (batadv_is_my_mac(bat_priv, req_dst))
3205		return batadv_send_my_tt_response(bat_priv, tt_data, req_src);
3206	return batadv_send_other_tt_response(bat_priv, tt_data, req_src,
3207					     req_dst);
3208}
3209
3210static void _batadv_tt_update_changes(struct batadv_priv *bat_priv,
3211				      struct batadv_orig_node *orig_node,
3212				      struct batadv_tvlv_tt_change *tt_change,
3213				      u16 tt_num_changes, u8 ttvn)
3214{
3215	int i;
3216	int roams;
3217
3218	for (i = 0; i < tt_num_changes; i++) {
3219		if ((tt_change + i)->flags & BATADV_TT_CLIENT_DEL) {
3220			roams = (tt_change + i)->flags & BATADV_TT_CLIENT_ROAM;
3221			batadv_tt_global_del(bat_priv, orig_node,
3222					     (tt_change + i)->addr,
3223					     ntohs((tt_change + i)->vid),
3224					     "tt removed by changes",
3225					     roams);
3226		} else {
3227			if (!batadv_tt_global_add(bat_priv, orig_node,
3228						  (tt_change + i)->addr,
3229						  ntohs((tt_change + i)->vid),
3230						  (tt_change + i)->flags, ttvn))
3231				/* In case of problem while storing a
3232				 * global_entry, we stop the updating
3233				 * procedure without committing the
3234				 * ttvn change. This will avoid to send
3235				 * corrupted data on tt_request
3236				 */
3237				return;
3238		}
3239	}
3240	set_bit(BATADV_ORIG_CAPA_HAS_TT, &orig_node->capa_initialized);
3241}
3242
3243static void batadv_tt_fill_gtable(struct batadv_priv *bat_priv,
3244				  struct batadv_tvlv_tt_change *tt_change,
3245				  u8 ttvn, u8 *resp_src,
3246				  u16 num_entries)
3247{
3248	struct batadv_orig_node *orig_node;
3249
3250	orig_node = batadv_orig_hash_find(bat_priv, resp_src);
3251	if (!orig_node)
3252		goto out;
3253
3254	/* Purge the old table first.. */
3255	batadv_tt_global_del_orig(bat_priv, orig_node, -1,
3256				  "Received full table");
3257
3258	_batadv_tt_update_changes(bat_priv, orig_node, tt_change, num_entries,
3259				  ttvn);
3260
3261	spin_lock_bh(&orig_node->tt_buff_lock);
3262	kfree(orig_node->tt_buff);
3263	orig_node->tt_buff_len = 0;
3264	orig_node->tt_buff = NULL;
3265	spin_unlock_bh(&orig_node->tt_buff_lock);
3266
3267	atomic_set(&orig_node->last_ttvn, ttvn);
3268
3269out:
3270	batadv_orig_node_put(orig_node);
3271}
3272
3273static void batadv_tt_update_changes(struct batadv_priv *bat_priv,
3274				     struct batadv_orig_node *orig_node,
3275				     u16 tt_num_changes, u8 ttvn,
3276				     struct batadv_tvlv_tt_change *tt_change)
3277{
3278	_batadv_tt_update_changes(bat_priv, orig_node, tt_change,
3279				  tt_num_changes, ttvn);
3280
3281	batadv_tt_save_orig_buffer(bat_priv, orig_node, tt_change,
3282				   batadv_tt_len(tt_num_changes));
3283	atomic_set(&orig_node->last_ttvn, ttvn);
3284}
3285
3286/**
3287 * batadv_is_my_client() - check if a client is served by the local node
3288 * @bat_priv: the bat priv with all the mesh interface information
3289 * @addr: the mac address of the client to check
3290 * @vid: VLAN identifier
3291 *
3292 * Return: true if the client is served by this node, false otherwise.
3293 */
3294bool batadv_is_my_client(struct batadv_priv *bat_priv, const u8 *addr,
3295			 unsigned short vid)
3296{
3297	struct batadv_tt_local_entry *tt_local_entry;
3298	bool ret = false;
3299
3300	tt_local_entry = batadv_tt_local_hash_find(bat_priv, addr, vid);
3301	if (!tt_local_entry)
3302		goto out;
3303	/* Check if the client has been logically deleted (but is kept for
3304	 * consistency purpose)
3305	 */
3306	if ((tt_local_entry->common.flags & BATADV_TT_CLIENT_PENDING) ||
3307	    (tt_local_entry->common.flags & BATADV_TT_CLIENT_ROAM))
3308		goto out;
3309	ret = true;
3310out:
3311	batadv_tt_local_entry_put(tt_local_entry);
3312	return ret;
3313}
3314
3315/**
3316 * batadv_handle_tt_response() - process incoming tt reply
3317 * @bat_priv: the bat priv with all the mesh interface information
3318 * @tt_data: tt data containing the tt request information
3319 * @resp_src: mac address of tt reply sender
3320 * @num_entries: number of tt change entries appended to the tt data
3321 */
3322static void batadv_handle_tt_response(struct batadv_priv *bat_priv,
3323				      struct batadv_tvlv_tt_data *tt_data,
3324				      u8 *resp_src, u16 num_entries)
3325{
3326	struct batadv_tt_req_node *node;
3327	struct hlist_node *safe;
3328	struct batadv_orig_node *orig_node = NULL;
3329	struct batadv_tvlv_tt_change *tt_change;
3330	u8 *tvlv_ptr = (u8 *)tt_data;
3331
3332	batadv_dbg(BATADV_DBG_TT, bat_priv,
3333		   "Received TT_RESPONSE from %pM for ttvn %d t_size: %d [%c]\n",
3334		   resp_src, tt_data->ttvn, num_entries,
3335		   ((tt_data->flags & BATADV_TT_FULL_TABLE) ? 'F' : '.'));
3336
3337	orig_node = batadv_orig_hash_find(bat_priv, resp_src);
3338	if (!orig_node)
3339		goto out;
3340
3341	spin_lock_bh(&orig_node->tt_lock);
3342
3343	tvlv_ptr += struct_size(tt_data, vlan_data, ntohs(tt_data->num_vlan));
3344
3345	tt_change = (struct batadv_tvlv_tt_change *)tvlv_ptr;
3346	if (tt_data->flags & BATADV_TT_FULL_TABLE) {
3347		batadv_tt_fill_gtable(bat_priv, tt_change, tt_data->ttvn,
3348				      resp_src, num_entries);
3349	} else {
3350		batadv_tt_update_changes(bat_priv, orig_node, num_entries,
3351					 tt_data->ttvn, tt_change);
3352	}
3353
3354	/* Recalculate the CRC for this orig_node and store it */
3355	batadv_tt_global_update_crc(bat_priv, orig_node);
3356
3357	spin_unlock_bh(&orig_node->tt_lock);
3358
3359	/* Delete the tt_req_node from pending tt_requests list */
3360	spin_lock_bh(&bat_priv->tt.req_list_lock);
3361	hlist_for_each_entry_safe(node, safe, &bat_priv->tt.req_list, list) {
3362		if (!batadv_compare_eth(node->addr, resp_src))
3363			continue;
3364		hlist_del_init(&node->list);
3365		batadv_tt_req_node_put(node);
3366	}
3367
3368	spin_unlock_bh(&bat_priv->tt.req_list_lock);
3369out:
3370	batadv_orig_node_put(orig_node);
3371}
3372
3373static void batadv_tt_roam_list_free(struct batadv_priv *bat_priv)
3374{
3375	struct batadv_tt_roam_node *node, *safe;
3376
3377	spin_lock_bh(&bat_priv->tt.roam_list_lock);
3378
3379	list_for_each_entry_safe(node, safe, &bat_priv->tt.roam_list, list) {
3380		list_del(&node->list);
3381		kmem_cache_free(batadv_tt_roam_cache, node);
3382	}
3383
3384	spin_unlock_bh(&bat_priv->tt.roam_list_lock);
3385}
3386
3387static void batadv_tt_roam_purge(struct batadv_priv *bat_priv)
3388{
3389	struct batadv_tt_roam_node *node, *safe;
3390
3391	spin_lock_bh(&bat_priv->tt.roam_list_lock);
3392	list_for_each_entry_safe(node, safe, &bat_priv->tt.roam_list, list) {
3393		if (!batadv_has_timed_out(node->first_time,
3394					  BATADV_ROAMING_MAX_TIME))
3395			continue;
3396
3397		list_del(&node->list);
3398		kmem_cache_free(batadv_tt_roam_cache, node);
3399	}
3400	spin_unlock_bh(&bat_priv->tt.roam_list_lock);
3401}
3402
3403/**
3404 * batadv_tt_check_roam_count() - check if a client has roamed too frequently
3405 * @bat_priv: the bat priv with all the mesh interface information
3406 * @client: mac address of the roaming client
3407 *
3408 * This function checks whether the client already reached the
3409 * maximum number of possible roaming phases. In this case the ROAMING_ADV
3410 * will not be sent.
3411 *
3412 * Return: true if the ROAMING_ADV can be sent, false otherwise
3413 */
3414static bool batadv_tt_check_roam_count(struct batadv_priv *bat_priv, u8 *client)
3415{
3416	struct batadv_tt_roam_node *tt_roam_node;
3417	bool ret = false;
3418
3419	spin_lock_bh(&bat_priv->tt.roam_list_lock);
3420	/* The new tt_req will be issued only if I'm not waiting for a
3421	 * reply from the same orig_node yet
3422	 */
3423	list_for_each_entry(tt_roam_node, &bat_priv->tt.roam_list, list) {
3424		if (!batadv_compare_eth(tt_roam_node->addr, client))
3425			continue;
3426
3427		if (batadv_has_timed_out(tt_roam_node->first_time,
3428					 BATADV_ROAMING_MAX_TIME))
3429			continue;
3430
3431		if (!batadv_atomic_dec_not_zero(&tt_roam_node->counter))
3432			/* Sorry, you roamed too many times! */
3433			goto unlock;
3434		ret = true;
3435		break;
3436	}
3437
3438	if (!ret) {
3439		tt_roam_node = kmem_cache_alloc(batadv_tt_roam_cache,
3440						GFP_ATOMIC);
3441		if (!tt_roam_node)
3442			goto unlock;
3443
3444		tt_roam_node->first_time = jiffies;
3445		atomic_set(&tt_roam_node->counter,
3446			   BATADV_ROAMING_MAX_COUNT - 1);
3447		ether_addr_copy(tt_roam_node->addr, client);
3448
3449		list_add(&tt_roam_node->list, &bat_priv->tt.roam_list);
3450		ret = true;
3451	}
3452
3453unlock:
3454	spin_unlock_bh(&bat_priv->tt.roam_list_lock);
3455	return ret;
3456}
3457
3458/**
3459 * batadv_send_roam_adv() - send a roaming advertisement message
3460 * @bat_priv: the bat priv with all the mesh interface information
3461 * @client: mac address of the roaming client
3462 * @vid: VLAN identifier
3463 * @orig_node: message destination
3464 *
3465 * Send a ROAMING_ADV message to the node which was previously serving this
3466 * client. This is done to inform the node that from now on all traffic destined
3467 * for this particular roamed client has to be forwarded to the sender of the
3468 * roaming message.
3469 */
3470static void batadv_send_roam_adv(struct batadv_priv *bat_priv, u8 *client,
3471				 unsigned short vid,
3472				 struct batadv_orig_node *orig_node)
3473{
3474	struct batadv_hard_iface *primary_if;
3475	struct batadv_tvlv_roam_adv tvlv_roam;
3476
3477	primary_if = batadv_primary_if_get_selected(bat_priv);
3478	if (!primary_if)
3479		goto out;
3480
3481	/* before going on we have to check whether the client has
3482	 * already roamed to us too many times
3483	 */
3484	if (!batadv_tt_check_roam_count(bat_priv, client))
3485		goto out;
3486
3487	batadv_dbg(BATADV_DBG_TT, bat_priv,
3488		   "Sending ROAMING_ADV to %pM (client %pM, vid: %d)\n",
3489		   orig_node->orig, client, batadv_print_vid(vid));
3490
3491	batadv_inc_counter(bat_priv, BATADV_CNT_TT_ROAM_ADV_TX);
3492
3493	memcpy(tvlv_roam.client, client, sizeof(tvlv_roam.client));
3494	tvlv_roam.vid = htons(vid);
3495
3496	batadv_tvlv_unicast_send(bat_priv, primary_if->net_dev->dev_addr,
3497				 orig_node->orig, BATADV_TVLV_ROAM, 1,
3498				 &tvlv_roam, sizeof(tvlv_roam));
3499
3500out:
3501	batadv_hardif_put(primary_if);
3502}
3503
3504static void batadv_tt_purge(struct work_struct *work)
3505{
3506	struct delayed_work *delayed_work;
3507	struct batadv_priv_tt *priv_tt;
3508	struct batadv_priv *bat_priv;
3509
3510	delayed_work = to_delayed_work(work);
3511	priv_tt = container_of(delayed_work, struct batadv_priv_tt, work);
3512	bat_priv = container_of(priv_tt, struct batadv_priv, tt);
3513
3514	batadv_tt_local_purge(bat_priv, BATADV_TT_LOCAL_TIMEOUT);
3515	batadv_tt_global_purge(bat_priv);
3516	batadv_tt_req_purge(bat_priv);
3517	batadv_tt_roam_purge(bat_priv);
3518
3519	queue_delayed_work(batadv_event_workqueue, &bat_priv->tt.work,
3520			   msecs_to_jiffies(BATADV_TT_WORK_PERIOD));
3521}
3522
3523/**
3524 * batadv_tt_free() - Free translation table of mesh interface
3525 * @bat_priv: the bat priv with all the mesh interface information
3526 */
3527void batadv_tt_free(struct batadv_priv *bat_priv)
3528{
3529	batadv_tvlv_handler_unregister(bat_priv, BATADV_TVLV_ROAM, 1);
3530
3531	batadv_tvlv_container_unregister(bat_priv, BATADV_TVLV_TT, 1);
3532	batadv_tvlv_handler_unregister(bat_priv, BATADV_TVLV_TT, 1);
3533
3534	cancel_delayed_work_sync(&bat_priv->tt.work);
3535
3536	batadv_tt_local_table_free(bat_priv);
3537	batadv_tt_global_table_free(bat_priv);
3538	batadv_tt_req_list_free(bat_priv);
3539	batadv_tt_changes_list_free(bat_priv);
3540	batadv_tt_roam_list_free(bat_priv);
3541
3542	kfree(bat_priv->tt.last_changeset);
3543}
3544
3545/**
3546 * batadv_tt_local_set_flags() - set or unset the specified flags on the local
3547 *  table and possibly count them in the TT size
3548 * @bat_priv: the bat priv with all the mesh interface information
3549 * @flags: the flag to switch
3550 * @enable: whether to set or unset the flag
3551 * @count: whether to increase the TT size by the number of changed entries
3552 */
3553static void batadv_tt_local_set_flags(struct batadv_priv *bat_priv, u16 flags,
3554				      bool enable, bool count)
3555{
3556	struct batadv_hashtable *hash = bat_priv->tt.local_hash;
3557	struct batadv_tt_common_entry *tt_common_entry;
3558	struct hlist_head *head;
3559	u32 i;
3560
3561	if (!hash)
3562		return;
3563
3564	for (i = 0; i < hash->size; i++) {
3565		head = &hash->table[i];
3566
3567		rcu_read_lock();
3568		hlist_for_each_entry_rcu(tt_common_entry,
3569					 head, hash_entry) {
3570			if (enable) {
3571				if ((tt_common_entry->flags & flags) == flags)
3572					continue;
3573				tt_common_entry->flags |= flags;
3574			} else {
3575				if (!(tt_common_entry->flags & flags))
3576					continue;
3577				tt_common_entry->flags &= ~flags;
3578			}
3579
3580			if (!count)
3581				continue;
3582
3583			batadv_tt_local_size_inc(bat_priv,
3584						 tt_common_entry->vid);
3585		}
3586		rcu_read_unlock();
3587	}
3588}
3589
3590/* Purge out all the tt local entries marked with BATADV_TT_CLIENT_PENDING */
3591static void batadv_tt_local_purge_pending_clients(struct batadv_priv *bat_priv)
3592{
3593	struct batadv_hashtable *hash = bat_priv->tt.local_hash;
3594	struct batadv_tt_common_entry *tt_common;
3595	struct batadv_tt_local_entry *tt_local;
3596	struct hlist_node *node_tmp;
3597	struct hlist_head *head;
3598	spinlock_t *list_lock; /* protects write access to the hash lists */
3599	u32 i;
3600
3601	if (!hash)
3602		return;
3603
3604	for (i = 0; i < hash->size; i++) {
3605		head = &hash->table[i];
3606		list_lock = &hash->list_locks[i];
3607
3608		spin_lock_bh(list_lock);
3609		hlist_for_each_entry_safe(tt_common, node_tmp, head,
3610					  hash_entry) {
3611			if (!(tt_common->flags & BATADV_TT_CLIENT_PENDING))
3612				continue;
3613
3614			batadv_dbg(BATADV_DBG_TT, bat_priv,
3615				   "Deleting local tt entry (%pM, vid: %d): pending\n",
3616				   tt_common->addr,
3617				   batadv_print_vid(tt_common->vid));
3618
3619			batadv_tt_local_size_dec(bat_priv, tt_common->vid);
3620			hlist_del_rcu(&tt_common->hash_entry);
3621			tt_local = container_of(tt_common,
3622						struct batadv_tt_local_entry,
3623						common);
3624
3625			batadv_tt_local_entry_put(tt_local);
3626		}
3627		spin_unlock_bh(list_lock);
3628	}
3629}
3630
3631/**
3632 * batadv_tt_local_commit_changes_nolock() - commit all pending local tt changes
3633 *  which have been queued in the time since the last commit
3634 * @bat_priv: the bat priv with all the mesh interface information
3635 *
3636 * Caller must hold tt->commit_lock.
3637 */
3638static void batadv_tt_local_commit_changes_nolock(struct batadv_priv *bat_priv)
3639{
3640	lockdep_assert_held(&bat_priv->tt.commit_lock);
3641
3642	if (READ_ONCE(bat_priv->tt.local_changes) == 0) {
3643		if (!batadv_atomic_dec_not_zero(&bat_priv->tt.ogm_append_cnt))
3644			batadv_tt_tvlv_container_update(bat_priv);
3645		return;
3646	}
3647
3648	batadv_tt_local_set_flags(bat_priv, BATADV_TT_CLIENT_NEW, false, true);
3649
3650	batadv_tt_local_purge_pending_clients(bat_priv);
3651	batadv_tt_local_update_crc(bat_priv);
3652
3653	/* Increment the TTVN only once per OGM interval */
3654	atomic_inc(&bat_priv->tt.vn);
3655	batadv_dbg(BATADV_DBG_TT, bat_priv,
3656		   "Local changes committed, updating to ttvn %u\n",
3657		   (u8)atomic_read(&bat_priv->tt.vn));
3658
3659	/* reset the sending counter */
3660	atomic_set(&bat_priv->tt.ogm_append_cnt, BATADV_TT_OGM_APPEND_MAX);
3661	batadv_tt_tvlv_container_update(bat_priv);
3662}
3663
3664/**
3665 * batadv_tt_local_commit_changes() - commit all pending local tt changes which
3666 *  have been queued in the time since the last commit
3667 * @bat_priv: the bat priv with all the mesh interface information
3668 */
3669void batadv_tt_local_commit_changes(struct batadv_priv *bat_priv)
3670{
3671	spin_lock_bh(&bat_priv->tt.commit_lock);
3672	batadv_tt_local_commit_changes_nolock(bat_priv);
3673	spin_unlock_bh(&bat_priv->tt.commit_lock);
3674}
3675
3676/**
3677 * batadv_is_ap_isolated() - Check if packet from upper layer should be dropped
3678 * @bat_priv: the bat priv with all the mesh interface information
3679 * @src: source mac address of packet
3680 * @dst: destination mac address of packet
3681 * @vid: vlan id of packet
3682 *
3683 * Return: true when src+dst(+vid) pair should be isolated, false otherwise
3684 */
3685bool batadv_is_ap_isolated(struct batadv_priv *bat_priv, u8 *src, u8 *dst,
3686			   unsigned short vid)
3687{
3688	struct batadv_tt_local_entry *tt_local_entry;
3689	struct batadv_tt_global_entry *tt_global_entry;
3690	struct batadv_meshif_vlan *vlan;
3691	bool ret = false;
3692
3693	vlan = batadv_meshif_vlan_get(bat_priv, vid);
3694	if (!vlan)
3695		return false;
3696
3697	if (!atomic_read(&vlan->ap_isolation))
3698		goto vlan_put;
3699
3700	tt_local_entry = batadv_tt_local_hash_find(bat_priv, dst, vid);
3701	if (!tt_local_entry)
3702		goto vlan_put;
3703
3704	tt_global_entry = batadv_tt_global_hash_find(bat_priv, src, vid);
3705	if (!tt_global_entry)
3706		goto local_entry_put;
3707
3708	if (_batadv_is_ap_isolated(tt_local_entry, tt_global_entry))
3709		ret = true;
3710
3711	batadv_tt_global_entry_put(tt_global_entry);
3712local_entry_put:
3713	batadv_tt_local_entry_put(tt_local_entry);
3714vlan_put:
3715	batadv_meshif_vlan_put(vlan);
3716	return ret;
3717}
3718
3719/**
3720 * batadv_tt_update_orig() - update global translation table with new tt
3721 *  information received via ogms
3722 * @bat_priv: the bat priv with all the mesh interface information
3723 * @orig_node: the orig_node of the ogm
3724 * @tt_buff: pointer to the first tvlv VLAN entry
3725 * @tt_num_vlan: number of tvlv VLAN entries
3726 * @tt_change: pointer to the first entry in the TT buffer
3727 * @tt_num_changes: number of tt changes inside the tt buffer
3728 * @ttvn: translation table version number of this changeset
3729 */
3730static void batadv_tt_update_orig(struct batadv_priv *bat_priv,
3731				  struct batadv_orig_node *orig_node,
3732				  const void *tt_buff, u16 tt_num_vlan,
3733				  struct batadv_tvlv_tt_change *tt_change,
3734				  u16 tt_num_changes, u8 ttvn)
3735{
3736	u8 orig_ttvn = (u8)atomic_read(&orig_node->last_ttvn);
3737	struct batadv_tvlv_tt_vlan_data *tt_vlan;
3738	bool full_table = true;
3739	bool has_tt_init;
3740
3741	tt_vlan = (struct batadv_tvlv_tt_vlan_data *)tt_buff;
3742	has_tt_init = test_bit(BATADV_ORIG_CAPA_HAS_TT,
3743			       &orig_node->capa_initialized);
3744
3745	/* orig table not initialised AND first diff is in the OGM OR the ttvn
3746	 * increased by one -> we can apply the attached changes
3747	 */
3748	if ((!has_tt_init && ttvn == 1) || ttvn - orig_ttvn == 1) {
3749		/* the OGM could not contain the changes due to their size or
3750		 * because they have already been sent BATADV_TT_OGM_APPEND_MAX
3751		 * times.
3752		 * In this case send a tt request
3753		 */
3754		if (!tt_num_changes) {
3755			full_table = false;
3756			goto request_table;
3757		}
3758
3759		spin_lock_bh(&orig_node->tt_lock);
3760
3761		batadv_tt_update_changes(bat_priv, orig_node, tt_num_changes,
3762					 ttvn, tt_change);
3763
3764		/* Even if we received the precomputed crc with the OGM, we
3765		 * prefer to recompute it to spot any possible inconsistency
3766		 * in the global table
3767		 */
3768		batadv_tt_global_update_crc(bat_priv, orig_node);
3769
3770		spin_unlock_bh(&orig_node->tt_lock);
3771
3772		/* The ttvn alone is not enough to guarantee consistency
3773		 * because a single value could represent different states
3774		 * (due to the wrap around). Thus a node has to check whether
3775		 * the resulting table (after applying the changes) is still
3776		 * consistent or not. E.g. a node could disconnect while its
3777		 * ttvn is X and reconnect on ttvn = X + TTVN_MAX: in this case
3778		 * checking the CRC value is mandatory to detect the
3779		 * inconsistency
3780		 */
3781		if (!batadv_tt_global_check_crc(orig_node, tt_vlan,
3782						tt_num_vlan))
3783			goto request_table;
3784	} else {
3785		/* if we missed more than one change or our tables are not
3786		 * in sync anymore -> request fresh tt data
3787		 */
3788		if (!has_tt_init || ttvn != orig_ttvn ||
3789		    !batadv_tt_global_check_crc(orig_node, tt_vlan,
3790						tt_num_vlan)) {
3791request_table:
3792			batadv_dbg(BATADV_DBG_TT, bat_priv,
3793				   "TT inconsistency for %pM. Need to retrieve the correct information (ttvn: %u last_ttvn: %u num_changes: %u)\n",
3794				   orig_node->orig, ttvn, orig_ttvn,
3795				   tt_num_changes);
3796			batadv_send_tt_request(bat_priv, orig_node, ttvn,
3797					       tt_vlan, tt_num_vlan,
3798					       full_table);
3799			return;
3800		}
3801	}
3802}
3803
3804/**
3805 * batadv_tt_global_client_is_roaming() - check if a client is marked as roaming
3806 * @bat_priv: the bat priv with all the mesh interface information
3807 * @addr: the mac address of the client to check
3808 * @vid: VLAN identifier
3809 *
3810 * Return: true if we know that the client has moved from its old originator
3811 * to another one. This entry is still kept for consistency purposes and will be
3812 * deleted later by a DEL or because of timeout
3813 */
3814bool batadv_tt_global_client_is_roaming(struct batadv_priv *bat_priv,
3815					u8 *addr, unsigned short vid)
3816{
3817	struct batadv_tt_global_entry *tt_global_entry;
3818	bool ret = false;
3819
3820	tt_global_entry = batadv_tt_global_hash_find(bat_priv, addr, vid);
3821	if (!tt_global_entry)
3822		goto out;
3823
3824	ret = tt_global_entry->common.flags & BATADV_TT_CLIENT_ROAM;
3825	batadv_tt_global_entry_put(tt_global_entry);
3826out:
3827	return ret;
3828}
3829
3830/**
3831 * batadv_tt_local_client_is_roaming() - tells whether the client is roaming
3832 * @bat_priv: the bat priv with all the mesh interface information
3833 * @addr: the mac address of the local client to query
3834 * @vid: VLAN identifier
3835 *
3836 * Return: true if the local client is known to be roaming (it is not served by
3837 * this node anymore) or not. If yes, the client is still present in the table
3838 * to keep the latter consistent with the node TTVN
3839 */
3840bool batadv_tt_local_client_is_roaming(struct batadv_priv *bat_priv,
3841				       u8 *addr, unsigned short vid)
3842{
3843	struct batadv_tt_local_entry *tt_local_entry;
3844	bool ret = false;
3845
3846	tt_local_entry = batadv_tt_local_hash_find(bat_priv, addr, vid);
3847	if (!tt_local_entry)
3848		goto out;
3849
3850	ret = tt_local_entry->common.flags & BATADV_TT_CLIENT_ROAM;
3851	batadv_tt_local_entry_put(tt_local_entry);
3852out:
3853	return ret;
3854}
3855
3856/**
3857 * batadv_tt_add_temporary_global_entry() - Add temporary entry to global TT
3858 * @bat_priv: the bat priv with all the mesh interface information
3859 * @orig_node: orig node which the temporary entry should be associated with
3860 * @addr: mac address of the client
3861 * @vid: VLAN id of the new temporary global translation table
3862 *
3863 * Return: true when temporary tt entry could be added, false otherwise
3864 */
3865bool batadv_tt_add_temporary_global_entry(struct batadv_priv *bat_priv,
3866					  struct batadv_orig_node *orig_node,
3867					  const unsigned char *addr,
3868					  unsigned short vid)
3869{
3870	/* ignore loop detect macs, they are not supposed to be in the tt local
3871	 * data as well.
3872	 */
3873	if (batadv_bla_is_loopdetect_mac(addr))
3874		return false;
3875
3876	if (!batadv_tt_global_add(bat_priv, orig_node, addr, vid,
3877				  BATADV_TT_CLIENT_TEMP,
3878				  atomic_read(&orig_node->last_ttvn)))
3879		return false;
3880
3881	batadv_dbg(BATADV_DBG_TT, bat_priv,
3882		   "Added temporary global client (addr: %pM, vid: %d, orig: %pM)\n",
3883		   addr, batadv_print_vid(vid), orig_node->orig);
3884
3885	return true;
3886}
3887
3888/**
3889 * batadv_tt_local_resize_to_mtu() - resize the local translation table fit the
3890 *  maximum packet size that can be transported through the mesh
3891 * @mesh_iface: netdev struct of the mesh interface
3892 *
3893 * Remove entries older than 'timeout' and half timeout if more entries need
3894 * to be removed.
3895 */
3896void batadv_tt_local_resize_to_mtu(struct net_device *mesh_iface)
3897{
3898	struct batadv_priv *bat_priv = netdev_priv(mesh_iface);
3899	int packet_size_max = atomic_read(&bat_priv->packet_size_max);
3900	int table_size, timeout = BATADV_TT_LOCAL_TIMEOUT / 2;
3901	bool reduced = false;
3902
3903	spin_lock_bh(&bat_priv->tt.commit_lock);
3904
3905	while (timeout) {
3906		table_size = batadv_tt_local_table_transmit_size(bat_priv);
3907		if (packet_size_max >= table_size)
3908			break;
3909
3910		batadv_tt_local_purge(bat_priv, timeout);
3911		batadv_tt_local_purge_pending_clients(bat_priv);
3912
3913		timeout /= 2;
3914		reduced = true;
3915		net_ratelimited_function(batadv_info, mesh_iface,
3916					 "Forced to purge local tt entries to fit new maximum fragment MTU (%i)\n",
3917					 packet_size_max);
3918	}
3919
3920	/* commit these changes immediately, to avoid synchronization problem
3921	 * with the TTVN
3922	 */
3923	if (reduced)
3924		batadv_tt_local_commit_changes_nolock(bat_priv);
3925
3926	spin_unlock_bh(&bat_priv->tt.commit_lock);
3927}
3928
3929/**
3930 * batadv_tt_tvlv_ogm_handler_v1() - process incoming tt tvlv container
3931 * @bat_priv: the bat priv with all the mesh interface information
3932 * @orig: the orig_node of the ogm
3933 * @flags: flags indicating the tvlv state (see batadv_tvlv_handler_flags)
3934 * @tvlv_value: tvlv buffer containing the gateway data
3935 * @tvlv_value_len: tvlv buffer length
3936 */
3937static void batadv_tt_tvlv_ogm_handler_v1(struct batadv_priv *bat_priv,
3938					  struct batadv_orig_node *orig,
3939					  u8 flags, void *tvlv_value,
3940					  u16 tvlv_value_len)
3941{
3942	struct batadv_tvlv_tt_change *tt_change;
3943	struct batadv_tvlv_tt_data *tt_data;
3944	u16 num_entries, num_vlan;
3945	size_t tt_data_sz;
3946
3947	if (tvlv_value_len < sizeof(*tt_data))
3948		return;
3949
3950	tt_data = tvlv_value;
3951	num_vlan = ntohs(tt_data->num_vlan);
3952
3953	tt_data_sz = struct_size(tt_data, vlan_data, num_vlan);
3954	if (tvlv_value_len < tt_data_sz)
3955		return;
3956
3957	tt_change = (struct batadv_tvlv_tt_change *)((void *)tt_data
3958						     + tt_data_sz);
3959	tvlv_value_len -= tt_data_sz;
3960
3961	num_entries = batadv_tt_entries(tvlv_value_len);
3962
3963	batadv_tt_update_orig(bat_priv, orig, tt_data->vlan_data, num_vlan,
3964			      tt_change, num_entries, tt_data->ttvn);
3965}
3966
3967/**
3968 * batadv_tt_tvlv_unicast_handler_v1() - process incoming (unicast) tt tvlv
3969 *  container
3970 * @bat_priv: the bat priv with all the mesh interface information
3971 * @src: mac address of tt tvlv sender
3972 * @dst: mac address of tt tvlv recipient
3973 * @tvlv_value: tvlv buffer containing the tt data
3974 * @tvlv_value_len: tvlv buffer length
3975 *
3976 * Return: NET_RX_DROP if the tt tvlv is to be re-routed, NET_RX_SUCCESS
3977 * otherwise.
3978 */
3979static int batadv_tt_tvlv_unicast_handler_v1(struct batadv_priv *bat_priv,
3980					     u8 *src, u8 *dst,
3981					     void *tvlv_value,
3982					     u16 tvlv_value_len)
3983{
3984	struct batadv_tvlv_tt_data *tt_data;
3985	u16 tt_vlan_len, tt_num_entries;
3986	char tt_flag;
3987	bool ret;
3988
3989	if (tvlv_value_len < sizeof(*tt_data))
3990		return NET_RX_SUCCESS;
3991
3992	tt_data = tvlv_value;
3993	tvlv_value_len -= sizeof(*tt_data);
3994
3995	tt_vlan_len = flex_array_size(tt_data, vlan_data,
3996				      ntohs(tt_data->num_vlan));
3997
3998	if (tvlv_value_len < tt_vlan_len)
3999		return NET_RX_SUCCESS;
4000
4001	tvlv_value_len -= tt_vlan_len;
4002	tt_num_entries = batadv_tt_entries(tvlv_value_len);
4003
4004	switch (tt_data->flags & BATADV_TT_DATA_TYPE_MASK) {
4005	case BATADV_TT_REQUEST:
4006		batadv_inc_counter(bat_priv, BATADV_CNT_TT_REQUEST_RX);
4007
4008		/* If this node cannot provide a TT response the tt_request is
4009		 * forwarded
4010		 */
4011		ret = batadv_send_tt_response(bat_priv, tt_data, src, dst);
4012		if (!ret) {
4013			if (tt_data->flags & BATADV_TT_FULL_TABLE)
4014				tt_flag = 'F';
4015			else
4016				tt_flag = '.';
4017
4018			batadv_dbg(BATADV_DBG_TT, bat_priv,
4019				   "Routing TT_REQUEST to %pM [%c]\n",
4020				   dst, tt_flag);
4021			/* tvlv API will re-route the packet */
4022			return NET_RX_DROP;
4023		}
4024		break;
4025	case BATADV_TT_RESPONSE:
4026		batadv_inc_counter(bat_priv, BATADV_CNT_TT_RESPONSE_RX);
4027
4028		if (batadv_is_my_mac(bat_priv, dst)) {
4029			batadv_handle_tt_response(bat_priv, tt_data,
4030						  src, tt_num_entries);
4031			return NET_RX_SUCCESS;
4032		}
4033
4034		if (tt_data->flags & BATADV_TT_FULL_TABLE)
4035			tt_flag =  'F';
4036		else
4037			tt_flag = '.';
4038
4039		batadv_dbg(BATADV_DBG_TT, bat_priv,
4040			   "Routing TT_RESPONSE to %pM [%c]\n", dst, tt_flag);
4041
4042		/* tvlv API will re-route the packet */
4043		return NET_RX_DROP;
4044	}
4045
4046	return NET_RX_SUCCESS;
4047}
4048
4049/**
4050 * batadv_roam_tvlv_unicast_handler_v1() - process incoming tt roam tvlv
4051 *  container
4052 * @bat_priv: the bat priv with all the mesh interface information
4053 * @src: mac address of tt tvlv sender
4054 * @dst: mac address of tt tvlv recipient
4055 * @tvlv_value: tvlv buffer containing the tt data
4056 * @tvlv_value_len: tvlv buffer length
4057 *
4058 * Return: NET_RX_DROP if the tt roam tvlv is to be re-routed, NET_RX_SUCCESS
4059 * otherwise.
4060 */
4061static int batadv_roam_tvlv_unicast_handler_v1(struct batadv_priv *bat_priv,
4062					       u8 *src, u8 *dst,
4063					       void *tvlv_value,
4064					       u16 tvlv_value_len)
4065{
4066	struct batadv_tvlv_roam_adv *roaming_adv;
4067	struct batadv_orig_node *orig_node = NULL;
4068
4069	/* If this node is not the intended recipient of the
4070	 * roaming advertisement the packet is forwarded
4071	 * (the tvlv API will re-route the packet).
4072	 */
4073	if (!batadv_is_my_mac(bat_priv, dst))
4074		return NET_RX_DROP;
4075
4076	if (tvlv_value_len < sizeof(*roaming_adv))
4077		goto out;
4078
4079	orig_node = batadv_orig_hash_find(bat_priv, src);
4080	if (!orig_node)
4081		goto out;
4082
4083	batadv_inc_counter(bat_priv, BATADV_CNT_TT_ROAM_ADV_RX);
4084	roaming_adv = tvlv_value;
4085
4086	batadv_dbg(BATADV_DBG_TT, bat_priv,
4087		   "Received ROAMING_ADV from %pM (client %pM)\n",
4088		   src, roaming_adv->client);
4089
4090	batadv_tt_global_add(bat_priv, orig_node, roaming_adv->client,
4091			     ntohs(roaming_adv->vid), BATADV_TT_CLIENT_ROAM,
4092			     atomic_read(&orig_node->last_ttvn) + 1);
4093
4094out:
4095	batadv_orig_node_put(orig_node);
4096	return NET_RX_SUCCESS;
4097}
4098
4099/**
4100 * batadv_tt_init() - initialise the translation table internals
4101 * @bat_priv: the bat priv with all the mesh interface information
4102 *
4103 * Return: 0 on success or negative error number in case of failure.
4104 */
4105int batadv_tt_init(struct batadv_priv *bat_priv)
4106{
4107	int ret;
4108
4109	/* synchronized flags must be remote */
4110	BUILD_BUG_ON(!(BATADV_TT_SYNC_MASK & BATADV_TT_REMOTE_MASK));
4111
4112	ret = batadv_tt_local_init(bat_priv);
4113	if (ret < 0)
4114		return ret;
4115
4116	ret = batadv_tt_global_init(bat_priv);
4117	if (ret < 0) {
4118		batadv_tt_local_table_free(bat_priv);
4119		return ret;
4120	}
4121
4122	batadv_tvlv_handler_register(bat_priv, batadv_tt_tvlv_ogm_handler_v1,
4123				     batadv_tt_tvlv_unicast_handler_v1, NULL,
4124				     BATADV_TVLV_TT, 1, BATADV_NO_FLAGS);
4125
4126	batadv_tvlv_handler_register(bat_priv, NULL,
4127				     batadv_roam_tvlv_unicast_handler_v1, NULL,
4128				     BATADV_TVLV_ROAM, 1, BATADV_NO_FLAGS);
4129
4130	INIT_DELAYED_WORK(&bat_priv->tt.work, batadv_tt_purge);
4131	queue_delayed_work(batadv_event_workqueue, &bat_priv->tt.work,
4132			   msecs_to_jiffies(BATADV_TT_WORK_PERIOD));
4133
4134	return 1;
4135}
4136
4137/**
4138 * batadv_tt_global_is_isolated() - check if a client is marked as isolated
4139 * @bat_priv: the bat priv with all the mesh interface information
4140 * @addr: the mac address of the client
4141 * @vid: the identifier of the VLAN where this client is connected
4142 *
4143 * Return: true if the client is marked with the TT_CLIENT_ISOLA flag, false
4144 * otherwise
4145 */
4146bool batadv_tt_global_is_isolated(struct batadv_priv *bat_priv,
4147				  const u8 *addr, unsigned short vid)
4148{
4149	struct batadv_tt_global_entry *tt;
4150	bool ret;
4151
4152	tt = batadv_tt_global_hash_find(bat_priv, addr, vid);
4153	if (!tt)
4154		return false;
4155
4156	ret = tt->common.flags & BATADV_TT_CLIENT_ISOLA;
4157
4158	batadv_tt_global_entry_put(tt);
4159
4160	return ret;
4161}
4162
4163/**
4164 * batadv_tt_cache_init() - Initialize tt memory object cache
4165 *
4166 * Return: 0 on success or negative error number in case of failure.
4167 */
4168int __init batadv_tt_cache_init(void)
4169{
4170	size_t tl_size = sizeof(struct batadv_tt_local_entry);
4171	size_t tg_size = sizeof(struct batadv_tt_global_entry);
4172	size_t tt_orig_size = sizeof(struct batadv_tt_orig_list_entry);
4173	size_t tt_change_size = sizeof(struct batadv_tt_change_node);
4174	size_t tt_req_size = sizeof(struct batadv_tt_req_node);
4175	size_t tt_roam_size = sizeof(struct batadv_tt_roam_node);
4176
4177	batadv_tl_cache = kmem_cache_create("batadv_tl_cache", tl_size, 0,
4178					    SLAB_HWCACHE_ALIGN, NULL);
4179	if (!batadv_tl_cache)
4180		return -ENOMEM;
4181
4182	batadv_tg_cache = kmem_cache_create("batadv_tg_cache", tg_size, 0,
4183					    SLAB_HWCACHE_ALIGN, NULL);
4184	if (!batadv_tg_cache)
4185		goto err_tt_tl_destroy;
4186
4187	batadv_tt_orig_cache = kmem_cache_create("batadv_tt_orig_cache",
4188						 tt_orig_size, 0,
4189						 SLAB_HWCACHE_ALIGN, NULL);
4190	if (!batadv_tt_orig_cache)
4191		goto err_tt_tg_destroy;
4192
4193	batadv_tt_change_cache = kmem_cache_create("batadv_tt_change_cache",
4194						   tt_change_size, 0,
4195						   SLAB_HWCACHE_ALIGN, NULL);
4196	if (!batadv_tt_change_cache)
4197		goto err_tt_orig_destroy;
4198
4199	batadv_tt_req_cache = kmem_cache_create("batadv_tt_req_cache",
4200						tt_req_size, 0,
4201						SLAB_HWCACHE_ALIGN, NULL);
4202	if (!batadv_tt_req_cache)
4203		goto err_tt_change_destroy;
4204
4205	batadv_tt_roam_cache = kmem_cache_create("batadv_tt_roam_cache",
4206						 tt_roam_size, 0,
4207						 SLAB_HWCACHE_ALIGN, NULL);
4208	if (!batadv_tt_roam_cache)
4209		goto err_tt_req_destroy;
4210
4211	return 0;
4212
4213err_tt_req_destroy:
4214	kmem_cache_destroy(batadv_tt_req_cache);
4215	batadv_tt_req_cache = NULL;
4216err_tt_change_destroy:
4217	kmem_cache_destroy(batadv_tt_change_cache);
4218	batadv_tt_change_cache = NULL;
4219err_tt_orig_destroy:
4220	kmem_cache_destroy(batadv_tt_orig_cache);
4221	batadv_tt_orig_cache = NULL;
4222err_tt_tg_destroy:
4223	kmem_cache_destroy(batadv_tg_cache);
4224	batadv_tg_cache = NULL;
4225err_tt_tl_destroy:
4226	kmem_cache_destroy(batadv_tl_cache);
4227	batadv_tl_cache = NULL;
4228
4229	return -ENOMEM;
4230}
4231
4232/**
4233 * batadv_tt_cache_destroy() - Destroy tt memory object cache
4234 */
4235void batadv_tt_cache_destroy(void)
4236{
4237	kmem_cache_destroy(batadv_tl_cache);
4238	kmem_cache_destroy(batadv_tg_cache);
4239	kmem_cache_destroy(batadv_tt_orig_cache);
4240	kmem_cache_destroy(batadv_tt_change_cache);
4241	kmem_cache_destroy(batadv_tt_req_cache);
4242	kmem_cache_destroy(batadv_tt_roam_cache);
4243}