net/batman-adv/translation-table.c

   1 /* Copyright (C) 2007-2012 B.A.T.M.A.N. contributors:
   2  *
   3  * Marek Lindner, Simon Wunderlich, Antonio Quartulli
   4  *
   5  * This program is free software; you can redistribute it and/or
   6  * modify it under the terms of version 2 of the GNU General Public
   7  * License as published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful, but
  10  * WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  12  * General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  17  * 02110-1301, USA
  18  */
  19
  20 #include "main.h"
  21 #include "translation-table.h"
  22 #include "soft-interface.h"
  23 #include "hard-interface.h"
  24 #include "send.h"
  25 #include "hash.h"
  26 #include "originator.h"
  27 #include "routing.h"
  28 #include "bridge_loop_avoidance.h"
  29
  30 #include <linux/crc16.h>
  31
  32 static void batadv_send_roam_adv(struct bat_priv *bat_priv, uint8_t *client,
  33                                  struct orig_node *orig_node);
  34 static void batadv_tt_purge(struct work_struct *work);
  35 static void
  36 batadv_tt_global_del_orig_list(struct tt_global_entry *tt_global_entry);
  37
  38 /* returns 1 if they are the same mac addr */
  39 static int batadv_compare_tt(const struct hlist_node *node, const void *data2)
  40 {
  41         const void *data1 = container_of(node, struct tt_common_entry,
  42                                          hash_entry);
  43
  44         return (memcmp(data1, data2, ETH_ALEN) == 0 ? 1 : 0);
  45 }
  46
  47 static void batadv_tt_start_timer(struct bat_priv *bat_priv)
  48 {
  49         INIT_DELAYED_WORK(&bat_priv->tt_work, batadv_tt_purge);
  50         queue_delayed_work(batadv_event_workqueue, &bat_priv->tt_work,
  51                            msecs_to_jiffies(5000));
  52 }
  53
  54 static struct tt_common_entry *batadv_tt_hash_find(struct hashtable_t *hash,
  55                                                    const void *data)
  56 {
  57         struct hlist_head *head;
  58         struct hlist_node *node;
  59         struct tt_common_entry *tt_common_entry, *tt_common_entry_tmp = NULL;
  60         uint32_t index;
  61
  62         if (!hash)
  63                 return NULL;
  64
  65         index = batadv_choose_orig(data, hash->size);
  66         head = &hash->table[index];
  67
  68         rcu_read_lock();
  69         hlist_for_each_entry_rcu(tt_common_entry, node, head, hash_entry) {
  70                 if (!batadv_compare_eth(tt_common_entry, data))
  71                         continue;
  72
  73                 if (!atomic_inc_not_zero(&tt_common_entry->refcount))
  74                         continue;
  75
  76                 tt_common_entry_tmp = tt_common_entry;
  77                 break;
  78         }
  79         rcu_read_unlock();
  80
  81         return tt_common_entry_tmp;
  82 }
  83
  84 static struct tt_local_entry *
  85 batadv_tt_local_hash_find(struct bat_priv *bat_priv, const void *data)
  86 {
  87         struct tt_common_entry *tt_common_entry;
  88         struct tt_local_entry *tt_local_entry = NULL;
  89
  90         tt_common_entry = batadv_tt_hash_find(bat_priv->tt_local_hash, data);
  91         if (tt_common_entry)
  92                 tt_local_entry = container_of(tt_common_entry,
  93                                               struct tt_local_entry, common);
  94         return tt_local_entry;
  95 }
  96
  97 static struct tt_global_entry *
  98 batadv_tt_global_hash_find(struct bat_priv *bat_priv, const void *data)
  99 {
 100         struct tt_common_entry *tt_common_entry;
 101         struct tt_global_entry *tt_global_entry = NULL;
 102
 103         tt_common_entry = batadv_tt_hash_find(bat_priv->tt_global_hash, data);
 104         if (tt_common_entry)
 105                 tt_global_entry = container_of(tt_common_entry,
 106                                                struct tt_global_entry, common);
 107         return tt_global_entry;
 108
 109 }
 110
 111 static void
 112 batadv_tt_local_entry_free_ref(struct tt_local_entry *tt_local_entry)
 113 {
 114         if (atomic_dec_and_test(&tt_local_entry->common.refcount))
 115                 kfree_rcu(tt_local_entry, common.rcu);
 116 }
 117
 118 static void batadv_tt_global_entry_free_rcu(struct rcu_head *rcu)
 119 {
 120         struct tt_common_entry *tt_common_entry;
 121         struct tt_global_entry *tt_global_entry;
 122
 123         tt_common_entry = container_of(rcu, struct tt_common_entry, rcu);
 124         tt_global_entry = container_of(tt_common_entry, struct tt_global_entry,
 125                                        common);
 126
 127         kfree(tt_global_entry);
 128 }
 129
 130 static void
 131 batadv_tt_global_entry_free_ref(struct tt_global_entry *tt_global_entry)
 132 {
 133         if (atomic_dec_and_test(&tt_global_entry->common.refcount)) {
 134                 batadv_tt_global_del_orig_list(tt_global_entry);
 135                 call_rcu(&tt_global_entry->common.rcu,
 136                          batadv_tt_global_entry_free_rcu);
 137         }
 138 }
 139
 140 static void batadv_tt_orig_list_entry_free_rcu(struct rcu_head *rcu)
 141 {
 142         struct tt_orig_list_entry *orig_entry;
 143
 144         orig_entry = container_of(rcu, struct tt_orig_list_entry, rcu);
 145         batadv_orig_node_free_ref(orig_entry->orig_node);
 146         kfree(orig_entry);
 147 }
 148
 149 static void
 150 batadv_tt_orig_list_entry_free_ref(struct tt_orig_list_entry *orig_entry)
 151 {
 152         /* to avoid race conditions, immediately decrease the tt counter */
 153         atomic_dec(&orig_entry->orig_node->tt_size);
 154         call_rcu(&orig_entry->rcu, batadv_tt_orig_list_entry_free_rcu);
 155 }
 156
 157 static void batadv_tt_local_event(struct bat_priv *bat_priv,
 158                                   const uint8_t *addr, uint8_t flags)
 159 {
 160         struct tt_change_node *tt_change_node, *entry, *safe;
 161         bool event_removed = false;
 162         bool del_op_requested, del_op_entry;
 163
 164         tt_change_node = kmalloc(sizeof(*tt_change_node), GFP_ATOMIC);
 165
 166         if (!tt_change_node)
 167                 return;
 168
 169         tt_change_node->change.flags = flags;
 170         memcpy(tt_change_node->change.addr, addr, ETH_ALEN);
 171
 172         del_op_requested = flags & TT_CLIENT_DEL;
 173
 174         /* check for ADD+DEL or DEL+ADD events */
 175         spin_lock_bh(&bat_priv->tt_changes_list_lock);
 176         list_for_each_entry_safe(entry, safe, &bat_priv->tt_changes_list,
 177                                  list) {
 178                 if (!batadv_compare_eth(entry->change.addr, addr))
 179                         continue;
 180
 181                 /* DEL+ADD in the same orig interval have no effect and can be
 182                  * removed to avoid silly behaviour on the receiver side. The
 183                  * other way around (ADD+DEL) can happen in case of roaming of
 184                  * a client still in the NEW state. Roaming of NEW clients is
 185                  * now possible due to automatically recognition of "temporary"
 186                  * clients
 187                  */
 188                 del_op_entry = entry->change.flags & TT_CLIENT_DEL;
 189                 if (!del_op_requested && del_op_entry)
 190                         goto del;
 191                 if (del_op_requested && !del_op_entry)
 192                         goto del;
 193                 continue;
 194 del:
 195                 list_del(&entry->list);
 196                 kfree(entry);
 197                 event_removed = true;
 198                 goto unlock;
 199         }
 200
 201         /* track the change in the OGMinterval list */
 202         list_add_tail(&tt_change_node->list, &bat_priv->tt_changes_list);
 203
 204 unlock:
 205         spin_unlock_bh(&bat_priv->tt_changes_list_lock);
 206
 207         if (event_removed)
 208                 atomic_dec(&bat_priv->tt_local_changes);
 209         else
 210                 atomic_inc(&bat_priv->tt_local_changes);
 211 }
 212
 213 int batadv_tt_len(int changes_num)
 214 {
 215         return changes_num * sizeof(struct tt_change);
 216 }
 217
 218 static int batadv_tt_local_init(struct bat_priv *bat_priv)
 219 {
 220         if (bat_priv->tt_local_hash)
 221                 return 0;
 222
 223         bat_priv->tt_local_hash = batadv_hash_new(1024);
 224
 225         if (!bat_priv->tt_local_hash)
 226                 return -ENOMEM;
 227
 228         return 0;
 229 }
 230
 231 void batadv_tt_local_add(struct net_device *soft_iface, const uint8_t *addr,
 232                          int ifindex)
 233 {
 234         struct bat_priv *bat_priv = netdev_priv(soft_iface);
 235         struct tt_local_entry *tt_local_entry = NULL;
 236         struct tt_global_entry *tt_global_entry = NULL;
 237         struct hlist_head *head;
 238         struct hlist_node *node;
 239         struct tt_orig_list_entry *orig_entry;
 240         int hash_added;
 241
 242         tt_local_entry = batadv_tt_local_hash_find(bat_priv, addr);
 243
 244         if (tt_local_entry) {
 245                 tt_local_entry->last_seen = jiffies;
 246                 /* possibly unset the TT_CLIENT_PENDING flag */
 247                 tt_local_entry->common.flags &= ~TT_CLIENT_PENDING;
 248                 goto out;
 249         }
 250
 251         tt_local_entry = kmalloc(sizeof(*tt_local_entry), GFP_ATOMIC);
 252         if (!tt_local_entry)
 253                 goto out;
 254
 255         batadv_dbg(DBG_TT, bat_priv,
 256                    "Creating new local tt entry: %pM (ttvn: %d)\n", addr,
 257                    (uint8_t)atomic_read(&bat_priv->ttvn));
 258
 259         memcpy(tt_local_entry->common.addr, addr, ETH_ALEN);
 260         tt_local_entry->common.flags = NO_FLAGS;
 261         if (batadv_is_wifi_iface(ifindex))
 262                 tt_local_entry->common.flags |= TT_CLIENT_WIFI;
 263         atomic_set(&tt_local_entry->common.refcount, 2);
 264         tt_local_entry->last_seen = jiffies;
 265
 266         /* the batman interface mac address should never be purged */
 267         if (batadv_compare_eth(addr, soft_iface->dev_addr))
 268                 tt_local_entry->common.flags |= TT_CLIENT_NOPURGE;
 269
 270         /* The local entry has to be marked as NEW to avoid to send it in
 271          * a full table response going out before the next ttvn increment
 272          * (consistency check)
 273          */
 274         tt_local_entry->common.flags |= TT_CLIENT_NEW;
 275
 276         hash_added = batadv_hash_add(bat_priv->tt_local_hash, batadv_compare_tt,
 277                                      batadv_choose_orig,
 278                                      &tt_local_entry->common,
 279                                      &tt_local_entry->common.hash_entry);
 280
 281         if (unlikely(hash_added != 0)) {
 282                 /* remove the reference for the hash */
 283                 batadv_tt_local_entry_free_ref(tt_local_entry);
 284                 goto out;
 285         }
 286
 287         batadv_tt_local_event(bat_priv, addr, tt_local_entry->common.flags);
 288
 289         /* remove address from global hash if present */
 290         tt_global_entry = batadv_tt_global_hash_find(bat_priv, addr);
 291
 292         /* Check whether it is a roaming! */
 293         if (tt_global_entry) {
 294                 /* These node are probably going to update their tt table */
 295                 head = &tt_global_entry->orig_list;
 296                 rcu_read_lock();
 297                 hlist_for_each_entry_rcu(orig_entry, node, head, list) {
 298                         orig_entry->orig_node->tt_poss_change = true;
 299
 300                         batadv_send_roam_adv(bat_priv,
 301                                              tt_global_entry->common.addr,
 302                                              orig_entry->orig_node);
 303                 }
 304                 rcu_read_unlock();
 305                 /* The global entry has to be marked as ROAMING and
 306                  * has to be kept for consistency purpose
 307                  */
 308                 tt_global_entry->common.flags |= TT_CLIENT_ROAM;
 309                 tt_global_entry->roam_at = jiffies;
 310         }
 311 out:
 312         if (tt_local_entry)
 313                 batadv_tt_local_entry_free_ref(tt_local_entry);
 314         if (tt_global_entry)
 315                 batadv_tt_global_entry_free_ref(tt_global_entry);
 316 }
 317
 318 static void batadv_tt_realloc_packet_buff(unsigned char **packet_buff,
 319                                           int *packet_buff_len,
 320                                           int min_packet_len,
 321                                           int new_packet_len)
 322 {
 323         unsigned char *new_buff;
 324
 325         new_buff = kmalloc(new_packet_len, GFP_ATOMIC);
 326
 327         /* keep old buffer if kmalloc should fail */
 328         if (new_buff) {
 329                 memcpy(new_buff, *packet_buff, min_packet_len);
 330                 kfree(*packet_buff);
 331                 *packet_buff = new_buff;
 332                 *packet_buff_len = new_packet_len;
 333         }
 334 }
 335
 336 static void batadv_tt_prepare_packet_buff(struct bat_priv *bat_priv,
 337                                           unsigned char **packet_buff,
 338                                           int *packet_buff_len,
 339                                           int min_packet_len)
 340 {
 341         struct hard_iface *primary_if;
 342         int req_len;
 343
 344         primary_if = batadv_primary_if_get_selected(bat_priv);
 345
 346         req_len = min_packet_len;
 347         req_len += batadv_tt_len(atomic_read(&bat_priv->tt_local_changes));
 348
 349         /* if we have too many changes for one packet don't send any
 350          * and wait for the tt table request which will be fragmented
 351          */
 352         if ((!primary_if) || (req_len > primary_if->soft_iface->mtu))
 353                 req_len = min_packet_len;
 354
 355         batadv_tt_realloc_packet_buff(packet_buff, packet_buff_len,
 356                                       min_packet_len, req_len);
 357
 358         if (primary_if)
 359                 batadv_hardif_free_ref(primary_if);
 360 }
 361
 362 static int batadv_tt_changes_fill_buff(struct bat_priv *bat_priv,
 363                                        unsigned char **packet_buff,
 364                                        int *packet_buff_len,
 365                                        int min_packet_len)
 366 {
 367         struct tt_change_node *entry, *safe;
 368         int count = 0, tot_changes = 0, new_len;
 369         unsigned char *tt_buff;
 370
 371         batadv_tt_prepare_packet_buff(bat_priv, packet_buff,
 372                                       packet_buff_len, min_packet_len);
 373
 374         new_len = *packet_buff_len - min_packet_len;
 375         tt_buff = *packet_buff + min_packet_len;
 376
 377         if (new_len > 0)
 378                 tot_changes = new_len / batadv_tt_len(1);
 379
 380         spin_lock_bh(&bat_priv->tt_changes_list_lock);
 381         atomic_set(&bat_priv->tt_local_changes, 0);
 382
 383         list_for_each_entry_safe(entry, safe, &bat_priv->tt_changes_list,
 384                                  list) {
 385                 if (count < tot_changes) {
 386                         memcpy(tt_buff + batadv_tt_len(count),
 387                                &entry->change, sizeof(struct tt_change));
 388                         count++;
 389                 }
 390                 list_del(&entry->list);
 391                 kfree(entry);
 392         }
 393         spin_unlock_bh(&bat_priv->tt_changes_list_lock);
 394
 395         /* Keep the buffer for possible tt_request */
 396         spin_lock_bh(&bat_priv->tt_buff_lock);
 397         kfree(bat_priv->tt_buff);
 398         bat_priv->tt_buff_len = 0;
 399         bat_priv->tt_buff = NULL;
 400         /* check whether this new OGM has no changes due to size problems */
 401         if (new_len > 0) {
 402                 /* if kmalloc() fails we will reply with the full table
 403                  * instead of providing the diff
 404                  */
 405                 bat_priv->tt_buff = kmalloc(new_len, GFP_ATOMIC);
 406                 if (bat_priv->tt_buff) {
 407                         memcpy(bat_priv->tt_buff, tt_buff, new_len);
 408                         bat_priv->tt_buff_len = new_len;
 409                 }
 410         }
 411         spin_unlock_bh(&bat_priv->tt_buff_lock);
 412
 413         return count;
 414 }
 415
 416 int batadv_tt_local_seq_print_text(struct seq_file *seq, void *offset)
 417 {
 418         struct net_device *net_dev = (struct net_device *)seq->private;
 419         struct bat_priv *bat_priv = netdev_priv(net_dev);
 420         struct hashtable_t *hash = bat_priv->tt_local_hash;
 421         struct tt_common_entry *tt_common_entry;
 422         struct hard_iface *primary_if;
 423         struct hlist_node *node;
 424         struct hlist_head *head;
 425         uint32_t i;
 426         int ret = 0;
 427
 428         primary_if = batadv_primary_if_get_selected(bat_priv);
 429         if (!primary_if) {
 430                 ret = seq_printf(seq,
 431                                  "BATMAN mesh %s disabled - please specify interfaces to enable it\n",
 432                                  net_dev->name);
 433                 goto out;
 434         }
 435
 436         if (primary_if->if_status != IF_ACTIVE) {
 437                 ret = seq_printf(seq,
 438                                  "BATMAN mesh %s disabled - primary interface not active\n",
 439                                  net_dev->name);
 440                 goto out;
 441         }
 442
 443         seq_printf(seq,
 444                    "Locally retrieved addresses (from %s) announced via TT (TTVN: %u):\n",
 445                    net_dev->name, (uint8_t)atomic_read(&bat_priv->ttvn));
 446
 447         for (i = 0; i < hash->size; i++) {
 448                 head = &hash->table[i];
 449
 450                 rcu_read_lock();
 451                 hlist_for_each_entry_rcu(tt_common_entry, node,
 452                                          head, hash_entry) {
 453                         seq_printf(seq, " * %pM [%c%c%c%c%c]\n",
 454                                    tt_common_entry->addr,
 455                                    (tt_common_entry->flags &
 456                                     TT_CLIENT_ROAM ? 'R' : '.'),
 457                                    (tt_common_entry->flags &
 458                                     TT_CLIENT_NOPURGE ? 'P' : '.'),
 459                                    (tt_common_entry->flags &
 460                                     TT_CLIENT_NEW ? 'N' : '.'),
 461                                    (tt_common_entry->flags &
 462                                     TT_CLIENT_PENDING ? 'X' : '.'),
 463                                    (tt_common_entry->flags &
 464                                     TT_CLIENT_WIFI ? 'W' : '.'));
 465                 }
 466                 rcu_read_unlock();
 467         }
 468 out:
 469         if (primary_if)
 470                 batadv_hardif_free_ref(primary_if);
 471         return ret;
 472 }
 473
 474 static void batadv_tt_local_set_pending(struct bat_priv *bat_priv,
 475                                         struct tt_local_entry *tt_local_entry,
 476                                         uint16_t flags, const char *message)
 477 {
 478         batadv_tt_local_event(bat_priv, tt_local_entry->common.addr,
 479                               tt_local_entry->common.flags | flags);
 480
 481         /* The local client has to be marked as "pending to be removed" but has
 482          * to be kept in the table in order to send it in a full table
 483          * response issued before the net ttvn increment (consistency check)
 484          */
 485         tt_local_entry->common.flags |= TT_CLIENT_PENDING;
 486
 487         batadv_dbg(DBG_TT, bat_priv,
 488                    "Local tt entry (%pM) pending to be removed: %s\n",
 489                    tt_local_entry->common.addr, message);
 490 }
 491
 492 void batadv_tt_local_remove(struct bat_priv *bat_priv, const uint8_t *addr,
 493                             const char *message, bool roaming)
 494 {
 495         struct tt_local_entry *tt_local_entry = NULL;
 496
 497         tt_local_entry = batadv_tt_local_hash_find(bat_priv, addr);
 498         if (!tt_local_entry)
 499                 goto out;
 500
 501         batadv_tt_local_set_pending(bat_priv, tt_local_entry, TT_CLIENT_DEL |
 502                                     (roaming ? TT_CLIENT_ROAM : NO_FLAGS),
 503                                     message);
 504 out:
 505         if (tt_local_entry)
 506                 batadv_tt_local_entry_free_ref(tt_local_entry);
 507 }
 508
 509 static void batadv_tt_local_purge(struct bat_priv *bat_priv)
 510 {
 511         struct hashtable_t *hash = bat_priv->tt_local_hash;
 512         struct tt_local_entry *tt_local_entry;
 513         struct tt_common_entry *tt_common_entry;
 514         struct hlist_node *node, *node_tmp;
 515         struct hlist_head *head;
 516         spinlock_t *list_lock; /* protects write access to the hash lists */
 517         uint32_t i;
 518
 519         for (i = 0; i < hash->size; i++) {
 520                 head = &hash->table[i];
 521                 list_lock = &hash->list_locks[i];
 522
 523                 spin_lock_bh(list_lock);
 524                 hlist_for_each_entry_safe(tt_common_entry, node, node_tmp,
 525                                           head, hash_entry) {
 526                         tt_local_entry = container_of(tt_common_entry,
 527                                                       struct tt_local_entry,
 528                                                       common);
 529                         if (tt_local_entry->common.flags & TT_CLIENT_NOPURGE)
 530                                 continue;
 531
 532                         /* entry already marked for deletion */
 533                         if (tt_local_entry->common.flags & TT_CLIENT_PENDING)
 534                                 continue;
 535
 536                         if (!batadv_has_timed_out(tt_local_entry->last_seen,
 537                                                   TT_LOCAL_TIMEOUT))
 538                                 continue;
 539
 540                         batadv_tt_local_set_pending(bat_priv, tt_local_entry,
 541                                                     TT_CLIENT_DEL, "timed out");
 542                 }
 543                 spin_unlock_bh(list_lock);
 544         }
 545
 546 }
 547
 548 static void batadv_tt_local_table_free(struct bat_priv *bat_priv)
 549 {
 550         struct hashtable_t *hash;
 551         spinlock_t *list_lock; /* protects write access to the hash lists */
 552         struct tt_common_entry *tt_common_entry;
 553         struct tt_local_entry *tt_local_entry;
 554         struct hlist_node *node, *node_tmp;
 555         struct hlist_head *head;
 556         uint32_t i;
 557
 558         if (!bat_priv->tt_local_hash)
 559                 return;
 560
 561         hash = bat_priv->tt_local_hash;
 562
 563         for (i = 0; i < hash->size; i++) {
 564                 head = &hash->table[i];
 565                 list_lock = &hash->list_locks[i];
 566
 567                 spin_lock_bh(list_lock);
 568                 hlist_for_each_entry_safe(tt_common_entry, node, node_tmp,
 569                                           head, hash_entry) {
 570                         hlist_del_rcu(node);
 571                         tt_local_entry = container_of(tt_common_entry,
 572                                                       struct tt_local_entry,
 573                                                       common);
 574                         batadv_tt_local_entry_free_ref(tt_local_entry);
 575                 }
 576                 spin_unlock_bh(list_lock);
 577         }
 578
 579         batadv_hash_destroy(hash);
 580
 581         bat_priv->tt_local_hash = NULL;
 582 }
 583
 584 static int batadv_tt_global_init(struct bat_priv *bat_priv)
 585 {
 586         if (bat_priv->tt_global_hash)
 587                 return 0;
 588
 589         bat_priv->tt_global_hash = batadv_hash_new(1024);
 590
 591         if (!bat_priv->tt_global_hash)
 592                 return -ENOMEM;
 593
 594         return 0;
 595 }
 596
 597 static void batadv_tt_changes_list_free(struct bat_priv *bat_priv)
 598 {
 599         struct tt_change_node *entry, *safe;
 600
 601         spin_lock_bh(&bat_priv->tt_changes_list_lock);
 602
 603         list_for_each_entry_safe(entry, safe, &bat_priv->tt_changes_list,
 604                                  list) {
 605                 list_del(&entry->list);
 606                 kfree(entry);
 607         }
 608
 609         atomic_set(&bat_priv->tt_local_changes, 0);
 610         spin_unlock_bh(&bat_priv->tt_changes_list_lock);
 611 }
 612
 613 /* find out if an orig_node is already in the list of a tt_global_entry.
 614  * returns 1 if found, 0 otherwise
 615  */
 616 static bool batadv_tt_global_entry_has_orig(const struct tt_global_entry *entry,
 617                                             const struct orig_node *orig_node)
 618 {
 619         struct tt_orig_list_entry *tmp_orig_entry;
 620         const struct hlist_head *head;
 621         struct hlist_node *node;
 622         bool found = false;
 623
 624         rcu_read_lock();
 625         head = &entry->orig_list;
 626         hlist_for_each_entry_rcu(tmp_orig_entry, node, head, list) {
 627                 if (tmp_orig_entry->orig_node == orig_node) {
 628                         found = true;
 629                         break;
 630                 }
 631         }
 632         rcu_read_unlock();
 633         return found;
 634 }
 635
 636 static void
 637 batadv_tt_global_add_orig_entry(struct tt_global_entry *tt_global_entry,
 638                                 struct orig_node *orig_node, int ttvn)
 639 {
 640         struct tt_orig_list_entry *orig_entry;
 641
 642         orig_entry = kzalloc(sizeof(*orig_entry), GFP_ATOMIC);
 643         if (!orig_entry)
 644                 return;
 645
 646         INIT_HLIST_NODE(&orig_entry->list);
 647         atomic_inc(&orig_node->refcount);
 648         atomic_inc(&orig_node->tt_size);
 649         orig_entry->orig_node = orig_node;
 650         orig_entry->ttvn = ttvn;
 651
 652         spin_lock_bh(&tt_global_entry->list_lock);
 653         hlist_add_head_rcu(&orig_entry->list,
 654                            &tt_global_entry->orig_list);
 655         spin_unlock_bh(&tt_global_entry->list_lock);
 656 }
 657
 658 /* caller must hold orig_node refcount */
 659 int batadv_tt_global_add(struct bat_priv *bat_priv, struct orig_node *orig_node,
 660                          const unsigned char *tt_addr, uint8_t flags,
 661                          uint8_t ttvn)
 662 {
 663         struct tt_global_entry *tt_global_entry = NULL;
 664         int ret = 0;
 665         int hash_added;
 666         struct tt_common_entry *common;
 667
 668         tt_global_entry = batadv_tt_global_hash_find(bat_priv, tt_addr);
 669
 670         if (!tt_global_entry) {
 671                 tt_global_entry = kzalloc(sizeof(*tt_global_entry), GFP_ATOMIC);
 672                 if (!tt_global_entry)
 673                         goto out;
 674
 675                 common = &tt_global_entry->common;
 676                 memcpy(common->addr, tt_addr, ETH_ALEN);
 677
 678                 common->flags = flags;
 679                 tt_global_entry->roam_at = 0;
 680                 atomic_set(&common->refcount, 2);
 681
 682                 INIT_HLIST_HEAD(&tt_global_entry->orig_list);
 683                 spin_lock_init(&tt_global_entry->list_lock);
 684
 685                 hash_added = batadv_hash_add(bat_priv->tt_global_hash,
 686                                              batadv_compare_tt,
 687                                              batadv_choose_orig, common,
 688                                              &common->hash_entry);
 689
 690                 if (unlikely(hash_added != 0)) {
 691                         /* remove the reference for the hash */
 692                         batadv_tt_global_entry_free_ref(tt_global_entry);
 693                         goto out_remove;
 694                 }
 695
 696                 batadv_tt_global_add_orig_entry(tt_global_entry, orig_node,
 697                                                 ttvn);
 698         } else {
 699                 /* there is already a global entry, use this one. */
 700
 701                 /* If there is the TT_CLIENT_ROAM flag set, there is only one
 702                  * originator left in the list and we previously received a
 703                  * delete + roaming change for this originator.
 704                  *
 705                  * We should first delete the old originator before adding the
 706                  * new one.
 707                  */
 708                 if (tt_global_entry->common.flags & TT_CLIENT_ROAM) {
 709                         batadv_tt_global_del_orig_list(tt_global_entry);
 710                         tt_global_entry->common.flags &= ~TT_CLIENT_ROAM;
 711                         tt_global_entry->roam_at = 0;
 712                 }
 713
 714                 if (!batadv_tt_global_entry_has_orig(tt_global_entry,
 715                                                      orig_node))
 716                         batadv_tt_global_add_orig_entry(tt_global_entry,
 717                                                         orig_node, ttvn);
 718         }
 719
 720         batadv_dbg(DBG_TT, bat_priv,
 721                    "Creating new global tt entry: %pM (via %pM)\n",
 722                    tt_global_entry->common.addr, orig_node->orig);
 723
 724 out_remove:
 725         /* remove address from local hash if present */
 726         batadv_tt_local_remove(bat_priv, tt_global_entry->common.addr,
 727                                "global tt received", flags & TT_CLIENT_ROAM);
 728         ret = 1;
 729 out:
 730         if (tt_global_entry)
 731                 batadv_tt_global_entry_free_ref(tt_global_entry);
 732         return ret;
 733 }
 734
 735 /* print all orig nodes who announce the address for this global entry.
 736  * it is assumed that the caller holds rcu_read_lock();
 737  */
 738 static void
 739 batadv_tt_global_print_entry(struct tt_global_entry *tt_global_entry,
 740                              struct seq_file *seq)
 741 {
 742         struct hlist_head *head;
 743         struct hlist_node *node;
 744         struct tt_orig_list_entry *orig_entry;
 745         struct tt_common_entry *tt_common_entry;
 746         uint16_t flags;
 747         uint8_t last_ttvn;
 748
 749         tt_common_entry = &tt_global_entry->common;
 750
 751         head = &tt_global_entry->orig_list;
 752
 753         hlist_for_each_entry_rcu(orig_entry, node, head, list) {
 754                 flags = tt_common_entry->flags;
 755                 last_ttvn = atomic_read(&orig_entry->orig_node->last_ttvn);
 756                 seq_printf(seq, " * %pM  (%3u) via %pM     (%3u)   [%c%c]\n",
 757                            tt_global_entry->common.addr, orig_entry->ttvn,
 758                            orig_entry->orig_node->orig, last_ttvn,
 759                            (flags & TT_CLIENT_ROAM ? 'R' : '.'),
 760                            (flags & TT_CLIENT_WIFI ? 'W' : '.'));
 761         }
 762 }
 763
 764 int batadv_tt_global_seq_print_text(struct seq_file *seq, void *offset)
 765 {
 766         struct net_device *net_dev = (struct net_device *)seq->private;
 767         struct bat_priv *bat_priv = netdev_priv(net_dev);
 768         struct hashtable_t *hash = bat_priv->tt_global_hash;
 769         struct tt_common_entry *tt_common_entry;
 770         struct tt_global_entry *tt_global_entry;
 771         struct hard_iface *primary_if;
 772         struct hlist_node *node;
 773         struct hlist_head *head;
 774         uint32_t i;
 775         int ret = 0;
 776
 777         primary_if = batadv_primary_if_get_selected(bat_priv);
 778         if (!primary_if) {
 779                 ret = seq_printf(seq,
 780                                  "BATMAN mesh %s disabled - please specify interfaces to enable it\n",
 781                                  net_dev->name);
 782                 goto out;
 783         }
 784
 785         if (primary_if->if_status != IF_ACTIVE) {
 786                 ret = seq_printf(seq,
 787                                  "BATMAN mesh %s disabled - primary interface not active\n",
 788                                  net_dev->name);
 789                 goto out;
 790         }
 791
 792         seq_printf(seq,
 793                    "Globally announced TT entries received via the mesh %s\n",
 794                    net_dev->name);
 795         seq_printf(seq, "       %-13s %s       %-15s %s %s\n",
 796                    "Client", "(TTVN)", "Originator", "(Curr TTVN)", "Flags");
 797
 798         for (i = 0; i < hash->size; i++) {
 799                 head = &hash->table[i];
 800
 801                 rcu_read_lock();
 802                 hlist_for_each_entry_rcu(tt_common_entry, node,
 803                                          head, hash_entry) {
 804                         tt_global_entry = container_of(tt_common_entry,
 805                                                        struct tt_global_entry,
 806                                                        common);
 807                         batadv_tt_global_print_entry(tt_global_entry, seq);
 808                 }
 809                 rcu_read_unlock();
 810         }
 811 out:
 812         if (primary_if)
 813                 batadv_hardif_free_ref(primary_if);
 814         return ret;
 815 }
 816
 817 /* deletes the orig list of a tt_global_entry */
 818 static void
 819 batadv_tt_global_del_orig_list(struct tt_global_entry *tt_global_entry)
 820 {
 821         struct hlist_head *head;
 822         struct hlist_node *node, *safe;
 823         struct tt_orig_list_entry *orig_entry;
 824
 825         spin_lock_bh(&tt_global_entry->list_lock);
 826         head = &tt_global_entry->orig_list;
 827         hlist_for_each_entry_safe(orig_entry, node, safe, head, list) {
 828                 hlist_del_rcu(node);
 829                 batadv_tt_orig_list_entry_free_ref(orig_entry);
 830         }
 831         spin_unlock_bh(&tt_global_entry->list_lock);
 832
 833 }
 834
 835 static void
 836 batadv_tt_global_del_orig_entry(struct bat_priv *bat_priv,
 837                                 struct tt_global_entry *tt_global_entry,
 838                                 struct orig_node *orig_node,
 839                                 const char *message)
 840 {
 841         struct hlist_head *head;
 842         struct hlist_node *node, *safe;
 843         struct tt_orig_list_entry *orig_entry;
 844
 845         spin_lock_bh(&tt_global_entry->list_lock);
 846         head = &tt_global_entry->orig_list;
 847         hlist_for_each_entry_safe(orig_entry, node, safe, head, list) {
 848                 if (orig_entry->orig_node == orig_node) {
 849                         batadv_dbg(DBG_TT, bat_priv,
 850                                    "Deleting %pM from global tt entry %pM: %s\n",
 851                                    orig_node->orig,
 852                                    tt_global_entry->common.addr, message);
 853                         hlist_del_rcu(node);
 854                         batadv_tt_orig_list_entry_free_ref(orig_entry);
 855                 }
 856         }
 857         spin_unlock_bh(&tt_global_entry->list_lock);
 858 }
 859
 860 static void batadv_tt_global_del_struct(struct bat_priv *bat_priv,
 861                                         struct tt_global_entry *tt_global_entry,
 862                                         const char *message)
 863 {
 864         batadv_dbg(DBG_TT, bat_priv, "Deleting global tt entry %pM: %s\n",
 865                    tt_global_entry->common.addr, message);
 866
 867         batadv_hash_remove(bat_priv->tt_global_hash, batadv_compare_tt,
 868                            batadv_choose_orig, tt_global_entry->common.addr);
 869         batadv_tt_global_entry_free_ref(tt_global_entry);
 870
 871 }
 872
 873 /* If the client is to be deleted, we check if it is the last origantor entry
 874  * within tt_global entry. If yes, we set the TT_CLIENT_ROAM flag and the timer,
 875  * otherwise we simply remove the originator scheduled for deletion.
 876  */
 877 static void
 878 batadv_tt_global_del_roaming(struct bat_priv *bat_priv,
 879                              struct tt_global_entry *tt_global_entry,
 880                              struct orig_node *orig_node, const char *message)
 881 {
 882         bool last_entry = true;
 883         struct hlist_head *head;
 884         struct hlist_node *node;
 885         struct tt_orig_list_entry *orig_entry;
 886
 887         /* no local entry exists, case 1:
 888          * Check if this is the last one or if other entries exist.
 889          */
 890
 891         rcu_read_lock();
 892         head = &tt_global_entry->orig_list;
 893         hlist_for_each_entry_rcu(orig_entry, node, head, list) {
 894                 if (orig_entry->orig_node != orig_node) {
 895                         last_entry = false;
 896                         break;
 897                 }
 898         }
 899         rcu_read_unlock();
 900
 901         if (last_entry) {
 902                 /* its the last one, mark for roaming. */
 903                 tt_global_entry->common.flags |= TT_CLIENT_ROAM;
 904                 tt_global_entry->roam_at = jiffies;
 905         } else
 906                 /* there is another entry, we can simply delete this
 907                  * one and can still use the other one.
 908                  */
 909                 batadv_tt_global_del_orig_entry(bat_priv, tt_global_entry,
 910                                                 orig_node, message);
 911 }
 912
 913
 914
 915 static void batadv_tt_global_del(struct bat_priv *bat_priv,
 916                                  struct orig_node *orig_node,
 917                                  const unsigned char *addr,
 918                                  const char *message, bool roaming)
 919 {
 920         struct tt_global_entry *tt_global_entry = NULL;
 921         struct tt_local_entry *local_entry = NULL;
 922
 923         tt_global_entry = batadv_tt_global_hash_find(bat_priv, addr);
 924         if (!tt_global_entry)
 925                 goto out;
 926
 927         if (!roaming) {
 928                 batadv_tt_global_del_orig_entry(bat_priv, tt_global_entry,
 929                                                 orig_node, message);
 930
 931                 if (hlist_empty(&tt_global_entry->orig_list))
 932                         batadv_tt_global_del_struct(bat_priv, tt_global_entry,
 933                                                     message);
 934
 935                 goto out;
 936         }
 937
 938         /* if we are deleting a global entry due to a roam
 939          * event, there are two possibilities:
 940          * 1) the client roamed from node A to node B => if there
 941          *    is only one originator left for this client, we mark
 942          *    it with TT_CLIENT_ROAM, we start a timer and we
 943          *    wait for node B to claim it. In case of timeout
 944          *    the entry is purged.
 945          *
 946          *    If there are other originators left, we directly delete
 947          *    the originator.
 948          * 2) the client roamed to us => we can directly delete
 949          *    the global entry, since it is useless now.
 950          */
 951         local_entry = batadv_tt_local_hash_find(bat_priv,
 952                                                 tt_global_entry->common.addr);
 953         if (local_entry) {
 954                 /* local entry exists, case 2: client roamed to us. */
 955                 batadv_tt_global_del_orig_list(tt_global_entry);
 956                 batadv_tt_global_del_struct(bat_priv, tt_global_entry, message);
 957         } else
 958                 /* no local entry exists, case 1: check for roaming */
 959                 batadv_tt_global_del_roaming(bat_priv, tt_global_entry,
 960                                              orig_node, message);
 961
 962
 963 out:
 964         if (tt_global_entry)
 965                 batadv_tt_global_entry_free_ref(tt_global_entry);
 966         if (local_entry)
 967                 batadv_tt_local_entry_free_ref(local_entry);
 968 }
 969
 970 void batadv_tt_global_del_orig(struct bat_priv *bat_priv,
 971                                struct orig_node *orig_node, const char *message)
 972 {
 973         struct tt_global_entry *global_entry;
 974         struct tt_common_entry *tt_common_entry;
 975         uint32_t i;
 976         struct hashtable_t *hash = bat_priv->tt_global_hash;
 977         struct hlist_node *node, *safe;
 978         struct hlist_head *head;
 979         spinlock_t *list_lock; /* protects write access to the hash lists */
 980
 981         if (!hash)
 982                 return;
 983
 984         for (i = 0; i < hash->size; i++) {
 985                 head = &hash->table[i];
 986                 list_lock = &hash->list_locks[i];
 987
 988                 spin_lock_bh(list_lock);
 989                 hlist_for_each_entry_safe(tt_common_entry, node, safe,
 990                                           head, hash_entry) {
 991                         global_entry = container_of(tt_common_entry,
 992                                                     struct tt_global_entry,
 993                                                     common);
 994
 995                         batadv_tt_global_del_orig_entry(bat_priv, global_entry,
 996                                                         orig_node, message);
 997
 998                         if (hlist_empty(&global_entry->orig_list)) {
 999                                 batadv_dbg(DBG_TT, bat_priv,
1000                                            "Deleting global tt entry %pM: %s\n",
1001                                            global_entry->common.addr, message);
1002                                 hlist_del_rcu(node);
1003                                 batadv_tt_global_entry_free_ref(global_entry);
1004                         }
1005                 }
1006                 spin_unlock_bh(list_lock);
1007         }
1008         orig_node->tt_initialised = false;
1009 }
1010
1011 static void batadv_tt_global_roam_purge(struct bat_priv *bat_priv)
1012 {
1013         struct hashtable_t *hash = bat_priv->tt_global_hash;
1014         struct tt_common_entry *tt_common_entry;
1015         struct tt_global_entry *tt_global_entry;
1016         struct hlist_node *node, *node_tmp;
1017         struct hlist_head *head;
1018         spinlock_t *list_lock; /* protects write access to the hash lists */
1019         uint32_t i;
1020
1021         for (i = 0; i < hash->size; i++) {
1022                 head = &hash->table[i];
1023                 list_lock = &hash->list_locks[i];
1024
1025                 spin_lock_bh(list_lock);
1026                 hlist_for_each_entry_safe(tt_common_entry, node, node_tmp,
1027                                           head, hash_entry) {
1028                         tt_global_entry = container_of(tt_common_entry,
1029                                                        struct tt_global_entry,
1030                                                        common);
1031                         if (!(tt_global_entry->common.flags & TT_CLIENT_ROAM))
1032                                 continue;
1033                         if (!batadv_has_timed_out(tt_global_entry->roam_at,
1034                                                   TT_CLIENT_ROAM_TIMEOUT))
1035                                 continue;
1036
1037                         batadv_dbg(DBG_TT, bat_priv,
1038                                    "Deleting global tt entry (%pM): Roaming timeout\n",
1039                                    tt_global_entry->common.addr);
1040
1041                         hlist_del_rcu(node);
1042                         batadv_tt_global_entry_free_ref(tt_global_entry);
1043                 }
1044                 spin_unlock_bh(list_lock);
1045         }
1046
1047 }
1048
1049 static void batadv_tt_global_table_free(struct bat_priv *bat_priv)
1050 {
1051         struct hashtable_t *hash;
1052         spinlock_t *list_lock; /* protects write access to the hash lists */
1053         struct tt_common_entry *tt_common_entry;
1054         struct tt_global_entry *tt_global_entry;
1055         struct hlist_node *node, *node_tmp;
1056         struct hlist_head *head;
1057         uint32_t i;
1058
1059         if (!bat_priv->tt_global_hash)
1060                 return;
1061
1062         hash = bat_priv->tt_global_hash;
1063
1064         for (i = 0; i < hash->size; i++) {
1065                 head = &hash->table[i];
1066                 list_lock = &hash->list_locks[i];
1067
1068                 spin_lock_bh(list_lock);
1069                 hlist_for_each_entry_safe(tt_common_entry, node, node_tmp,
1070                                           head, hash_entry) {
1071                         hlist_del_rcu(node);
1072                         tt_global_entry = container_of(tt_common_entry,
1073                                                        struct tt_global_entry,
1074                                                        common);
1075                         batadv_tt_global_entry_free_ref(tt_global_entry);
1076                 }
1077                 spin_unlock_bh(list_lock);
1078         }
1079
1080         batadv_hash_destroy(hash);
1081
1082         bat_priv->tt_global_hash = NULL;
1083 }
1084
1085 static bool _batadv_is_ap_isolated(struct tt_local_entry *tt_local_entry,
1086                                    struct tt_global_entry *tt_global_entry)
1087 {
1088         bool ret = false;
1089
1090         if (tt_local_entry->common.flags & TT_CLIENT_WIFI &&
1091             tt_global_entry->common.flags & TT_CLIENT_WIFI)
1092                 ret = true;
1093
1094         return ret;
1095 }
1096
1097 struct orig_node *batadv_transtable_search(struct bat_priv *bat_priv,
1098                                            const uint8_t *src,
1099                                            const uint8_t *addr)
1100 {
1101         struct tt_local_entry *tt_local_entry = NULL;
1102         struct tt_global_entry *tt_global_entry = NULL;
1103         struct orig_node *orig_node = NULL;
1104         struct neigh_node *router = NULL;
1105         struct hlist_head *head;
1106         struct hlist_node *node;
1107         struct tt_orig_list_entry *orig_entry;
1108         int best_tq;
1109
1110         if (src && atomic_read(&bat_priv->ap_isolation)) {
1111                 tt_local_entry = batadv_tt_local_hash_find(bat_priv, src);
1112                 if (!tt_local_entry)
1113                         goto out;
1114         }
1115
1116         tt_global_entry = batadv_tt_global_hash_find(bat_priv, addr);
1117         if (!tt_global_entry)
1118                 goto out;
1119
1120         /* check whether the clients should not communicate due to AP
1121          * isolation
1122          */
1123         if (tt_local_entry &&
1124             _batadv_is_ap_isolated(tt_local_entry, tt_global_entry))
1125                 goto out;
1126
1127         best_tq = 0;
1128
1129         rcu_read_lock();
1130         head = &tt_global_entry->orig_list;
1131         hlist_for_each_entry_rcu(orig_entry, node, head, list) {
1132                 router = batadv_orig_node_get_router(orig_entry->orig_node);
1133                 if (!router)
1134                         continue;
1135
1136                 if (router->tq_avg > best_tq) {
1137                         orig_node = orig_entry->orig_node;
1138                         best_tq = router->tq_avg;
1139                 }
1140                 batadv_neigh_node_free_ref(router);
1141         }
1142         /* found anything? */
1143         if (orig_node && !atomic_inc_not_zero(&orig_node->refcount))
1144                 orig_node = NULL;
1145         rcu_read_unlock();
1146 out:
1147         if (tt_global_entry)
1148                 batadv_tt_global_entry_free_ref(tt_global_entry);
1149         if (tt_local_entry)
1150                 batadv_tt_local_entry_free_ref(tt_local_entry);
1151
1152         return orig_node;
1153 }
1154
1155 /* Calculates the checksum of the local table of a given orig_node */
1156 static uint16_t batadv_tt_global_crc(struct bat_priv *bat_priv,
1157                                      struct orig_node *orig_node)
1158 {
1159         uint16_t total = 0, total_one;
1160         struct hashtable_t *hash = bat_priv->tt_global_hash;
1161         struct tt_common_entry *tt_common_entry;
1162         struct tt_global_entry *tt_global_entry;
1163         struct hlist_node *node;
1164         struct hlist_head *head;
1165         uint32_t i;
1166         int j;
1167
1168         for (i = 0; i < hash->size; i++) {
1169                 head = &hash->table[i];
1170
1171                 rcu_read_lock();
1172                 hlist_for_each_entry_rcu(tt_common_entry, node,
1173                                          head, hash_entry) {
1174                         tt_global_entry = container_of(tt_common_entry,
1175                                                        struct tt_global_entry,
1176                                                        common);
1177                         /* Roaming clients are in the global table for
1178                          * consistency only. They don't have to be
1179                          * taken into account while computing the
1180                          * global crc
1181                          */
1182                         if (tt_global_entry->common.flags & TT_CLIENT_ROAM)
1183                                 continue;
1184
1185                         /* find out if this global entry is announced by this
1186                          * originator
1187                          */
1188                         if (!batadv_tt_global_entry_has_orig(tt_global_entry,
1189                                                              orig_node))
1190                                 continue;
1191
1192                         total_one = 0;
1193                         for (j = 0; j < ETH_ALEN; j++)
1194                                 total_one = crc16_byte(total_one,
1195                                         tt_global_entry->common.addr[j]);
1196                         total ^= total_one;
1197                 }
1198                 rcu_read_unlock();
1199         }
1200
1201         return total;
1202 }
1203
1204 /* Calculates the checksum of the local table */
1205 static uint16_t batadv_tt_local_crc(struct bat_priv *bat_priv)
1206 {
1207         uint16_t total = 0, total_one;
1208         struct hashtable_t *hash = bat_priv->tt_local_hash;
1209         struct tt_common_entry *tt_common_entry;
1210         struct hlist_node *node;
1211         struct hlist_head *head;
1212         uint32_t i;
1213         int j;
1214
1215         for (i = 0; i < hash->size; i++) {
1216                 head = &hash->table[i];
1217
1218                 rcu_read_lock();
1219                 hlist_for_each_entry_rcu(tt_common_entry, node,
1220                                          head, hash_entry) {
1221                         /* not yet committed clients have not to be taken into
1222                          * account while computing the CRC
1223                          */
1224                         if (tt_common_entry->flags & TT_CLIENT_NEW)
1225                                 continue;
1226                         total_one = 0;
1227                         for (j = 0; j < ETH_ALEN; j++)
1228                                 total_one = crc16_byte(total_one,
1229                                                    tt_common_entry->addr[j]);
1230                         total ^= total_one;
1231                 }
1232                 rcu_read_unlock();
1233         }
1234
1235         return total;
1236 }
1237
1238 static void batadv_tt_req_list_free(struct bat_priv *bat_priv)
1239 {
1240         struct tt_req_node *node, *safe;
1241
1242         spin_lock_bh(&bat_priv->tt_req_list_lock);
1243
1244         list_for_each_entry_safe(node, safe, &bat_priv->tt_req_list, list) {
1245                 list_del(&node->list);
1246                 kfree(node);
1247         }
1248
1249         spin_unlock_bh(&bat_priv->tt_req_list_lock);
1250 }
1251
1252 static void batadv_tt_save_orig_buffer(struct bat_priv *bat_priv,
1253                                        struct orig_node *orig_node,
1254                                        const unsigned char *tt_buff,
1255                                        uint8_t tt_num_changes)
1256 {
1257         uint16_t tt_buff_len = batadv_tt_len(tt_num_changes);
1258
1259         /* Replace the old buffer only if I received something in the
1260          * last OGM (the OGM could carry no changes)
1261          */
1262         spin_lock_bh(&orig_node->tt_buff_lock);
1263         if (tt_buff_len > 0) {
1264                 kfree(orig_node->tt_buff);
1265                 orig_node->tt_buff_len = 0;
1266                 orig_node->tt_buff = kmalloc(tt_buff_len, GFP_ATOMIC);
1267                 if (orig_node->tt_buff) {
1268                         memcpy(orig_node->tt_buff, tt_buff, tt_buff_len);
1269                         orig_node->tt_buff_len = tt_buff_len;
1270                 }
1271         }
1272         spin_unlock_bh(&orig_node->tt_buff_lock);
1273 }
1274
1275 static void batadv_tt_req_purge(struct bat_priv *bat_priv)
1276 {
1277         struct tt_req_node *node, *safe;
1278
1279         spin_lock_bh(&bat_priv->tt_req_list_lock);
1280         list_for_each_entry_safe(node, safe, &bat_priv->tt_req_list, list) {
1281                 if (batadv_has_timed_out(node->issued_at, TT_REQUEST_TIMEOUT)) {
1282                         list_del(&node->list);
1283                         kfree(node);
1284                 }
1285         }
1286         spin_unlock_bh(&bat_priv->tt_req_list_lock);
1287 }
1288
1289 /* returns the pointer to the new tt_req_node struct if no request
1290  * has already been issued for this orig_node, NULL otherwise
1291  */
1292 static struct tt_req_node *batadv_new_tt_req_node(struct bat_priv *bat_priv,
1293                                                   struct orig_node *orig_node)
1294 {
1295         struct tt_req_node *tt_req_node_tmp, *tt_req_node = NULL;
1296
1297         spin_lock_bh(&bat_priv->tt_req_list_lock);
1298         list_for_each_entry(tt_req_node_tmp, &bat_priv->tt_req_list, list) {
1299                 if (batadv_compare_eth(tt_req_node_tmp, orig_node) &&
1300                     !batadv_has_timed_out(tt_req_node_tmp->issued_at,
1301                                           TT_REQUEST_TIMEOUT))
1302                         goto unlock;
1303         }
1304
1305         tt_req_node = kmalloc(sizeof(*tt_req_node), GFP_ATOMIC);
1306         if (!tt_req_node)
1307                 goto unlock;
1308
1309         memcpy(tt_req_node->addr, orig_node->orig, ETH_ALEN);
1310         tt_req_node->issued_at = jiffies;
1311
1312         list_add(&tt_req_node->list, &bat_priv->tt_req_list);
1313 unlock:
1314         spin_unlock_bh(&bat_priv->tt_req_list_lock);
1315         return tt_req_node;
1316 }
1317
1318 /* data_ptr is useless here, but has to be kept to respect the prototype */
1319 static int batadv_tt_local_valid_entry(const void *entry_ptr,
1320                                        const void *data_ptr)
1321 {
1322         const struct tt_common_entry *tt_common_entry = entry_ptr;
1323
1324         if (tt_common_entry->flags & TT_CLIENT_NEW)
1325                 return 0;
1326         return 1;
1327 }
1328
1329 static int batadv_tt_global_valid(const void *entry_ptr,
1330                                   const void *data_ptr)
1331 {
1332         const struct tt_common_entry *tt_common_entry = entry_ptr;
1333         const struct tt_global_entry *tt_global_entry;
1334         const struct orig_node *orig_node = data_ptr;
1335
1336         if (tt_common_entry->flags & TT_CLIENT_ROAM)
1337                 return 0;
1338
1339         tt_global_entry = container_of(tt_common_entry, struct tt_global_entry,
1340                                        common);
1341
1342         return batadv_tt_global_entry_has_orig(tt_global_entry, orig_node);
1343 }
1344
1345 static struct sk_buff *
1346 batadv_tt_response_fill_table(uint16_t tt_len, uint8_t ttvn,
1347                               struct hashtable_t *hash,
1348                               struct hard_iface *primary_if,
1349                               int (*valid_cb)(const void *, const void *),
1350                               void *cb_data)
1351 {
1352         struct tt_common_entry *tt_common_entry;
1353         struct tt_query_packet *tt_response;
1354         struct tt_change *tt_change;
1355         struct hlist_node *node;
1356         struct hlist_head *head;
1357         struct sk_buff *skb = NULL;
1358         uint16_t tt_tot, tt_count;
1359         ssize_t tt_query_size = sizeof(struct tt_query_packet);
1360         uint32_t i;
1361
1362         if (tt_query_size + tt_len > primary_if->soft_iface->mtu) {
1363                 tt_len = primary_if->soft_iface->mtu - tt_query_size;
1364                 tt_len -= tt_len % sizeof(struct tt_change);
1365         }
1366         tt_tot = tt_len / sizeof(struct tt_change);
1367
1368         skb = dev_alloc_skb(tt_query_size + tt_len + ETH_HLEN);
1369         if (!skb)
1370                 goto out;
1371
1372         skb_reserve(skb, ETH_HLEN);
1373         tt_response = (struct tt_query_packet *)skb_put(skb,
1374                                                      tt_query_size + tt_len);
1375         tt_response->ttvn = ttvn;
1376
1377         tt_change = (struct tt_change *)(skb->data + tt_query_size);
1378         tt_count = 0;
1379
1380         rcu_read_lock();
1381         for (i = 0; i < hash->size; i++) {
1382                 head = &hash->table[i];
1383
1384                 hlist_for_each_entry_rcu(tt_common_entry, node,
1385                                          head, hash_entry) {
1386                         if (tt_count == tt_tot)
1387                                 break;
1388
1389                         if ((valid_cb) && (!valid_cb(tt_common_entry, cb_data)))
1390                                 continue;
1391
1392                         memcpy(tt_change->addr, tt_common_entry->addr,
1393                                ETH_ALEN);
1394                         tt_change->flags = NO_FLAGS;
1395
1396                         tt_count++;
1397                         tt_change++;
1398                 }
1399         }
1400         rcu_read_unlock();
1401
1402         /* store in the message the number of entries we have successfully
1403          * copied
1404          */
1405         tt_response->tt_data = htons(tt_count);
1406
1407 out:
1408         return skb;
1409 }
1410
1411 static int batadv_send_tt_request(struct bat_priv *bat_priv,
1412                                   struct orig_node *dst_orig_node,
1413                                   uint8_t ttvn, uint16_t tt_crc,
1414                                   bool full_table)
1415 {
1416         struct sk_buff *skb = NULL;
1417         struct tt_query_packet *tt_request;
1418         struct neigh_node *neigh_node = NULL;
1419         struct hard_iface *primary_if;
1420         struct tt_req_node *tt_req_node = NULL;
1421         int ret = 1;
1422
1423         primary_if = batadv_primary_if_get_selected(bat_priv);
1424         if (!primary_if)
1425                 goto out;
1426
1427         /* The new tt_req will be issued only if I'm not waiting for a
1428          * reply from the same orig_node yet
1429          */
1430         tt_req_node = batadv_new_tt_req_node(bat_priv, dst_orig_node);
1431         if (!tt_req_node)
1432                 goto out;
1433
1434         skb = dev_alloc_skb(sizeof(struct tt_query_packet) + ETH_HLEN);
1435         if (!skb)
1436                 goto out;
1437
1438         skb_reserve(skb, ETH_HLEN);
1439
1440         tt_request = (struct tt_query_packet *)skb_put(skb,
1441                                 sizeof(struct tt_query_packet));
1442
1443         tt_request->header.packet_type = BAT_TT_QUERY;
1444         tt_request->header.version = COMPAT_VERSION;
1445         memcpy(tt_request->src, primary_if->net_dev->dev_addr, ETH_ALEN);
1446         memcpy(tt_request->dst, dst_orig_node->orig, ETH_ALEN);
1447         tt_request->header.ttl = TTL;
1448         tt_request->ttvn = ttvn;
1449         tt_request->tt_data = htons(tt_crc);
1450         tt_request->flags = TT_REQUEST;
1451
1452         if (full_table)
1453                 tt_request->flags |= TT_FULL_TABLE;
1454
1455         neigh_node = batadv_orig_node_get_router(dst_orig_node);
1456         if (!neigh_node)
1457                 goto out;
1458
1459         batadv_dbg(DBG_TT, bat_priv,
1460                    "Sending TT_REQUEST to %pM via %pM [%c]\n",
1461                    dst_orig_node->orig, neigh_node->addr,
1462                    (full_table ? 'F' : '.'));
1463
1464         batadv_inc_counter(bat_priv, BAT_CNT_TT_REQUEST_TX);
1465
1466         batadv_send_skb_packet(skb, neigh_node->if_incoming, neigh_node->addr);
1467         ret = 0;
1468
1469 out:
1470         if (neigh_node)
1471                 batadv_neigh_node_free_ref(neigh_node);
1472         if (primary_if)
1473                 batadv_hardif_free_ref(primary_if);
1474         if (ret)
1475                 kfree_skb(skb);
1476         if (ret && tt_req_node) {
1477                 spin_lock_bh(&bat_priv->tt_req_list_lock);
1478                 list_del(&tt_req_node->list);
1479                 spin_unlock_bh(&bat_priv->tt_req_list_lock);
1480                 kfree(tt_req_node);
1481         }
1482         return ret;
1483 }
1484
1485 static bool batadv_send_other_tt_response(struct bat_priv *bat_priv,
1486                                           struct tt_query_packet *tt_request)
1487 {
1488         struct orig_node *req_dst_orig_node = NULL, *res_dst_orig_node = NULL;
1489         struct neigh_node *neigh_node = NULL;
1490         struct hard_iface *primary_if = NULL;
1491         uint8_t orig_ttvn, req_ttvn, ttvn;
1492         int ret = false;
1493         unsigned char *tt_buff;
1494         bool full_table;
1495         uint16_t tt_len, tt_tot;
1496         struct sk_buff *skb = NULL;
1497         struct tt_query_packet *tt_response;
1498
1499         batadv_dbg(DBG_TT, bat_priv,
1500                    "Received TT_REQUEST from %pM for ttvn: %u (%pM) [%c]\n",
1501                    tt_request->src, tt_request->ttvn, tt_request->dst,
1502                    (tt_request->flags & TT_FULL_TABLE ? 'F' : '.'));
1503
1504         /* Let's get the orig node of the REAL destination */
1505         req_dst_orig_node = batadv_orig_hash_find(bat_priv, tt_request->dst);
1506         if (!req_dst_orig_node)
1507                 goto out;
1508
1509         res_dst_orig_node = batadv_orig_hash_find(bat_priv, tt_request->src);
1510         if (!res_dst_orig_node)
1511                 goto out;
1512
1513         neigh_node = batadv_orig_node_get_router(res_dst_orig_node);
1514         if (!neigh_node)
1515                 goto out;
1516
1517         primary_if = batadv_primary_if_get_selected(bat_priv);
1518         if (!primary_if)
1519                 goto out;
1520
1521         orig_ttvn = (uint8_t)atomic_read(&req_dst_orig_node->last_ttvn);
1522         req_ttvn = tt_request->ttvn;
1523
1524         /* I don't have the requested data */
1525         if (orig_ttvn != req_ttvn ||
1526             tt_request->tt_data != htons(req_dst_orig_node->tt_crc))
1527                 goto out;
1528
1529         /* If the full table has been explicitly requested */
1530         if (tt_request->flags & TT_FULL_TABLE ||
1531             !req_dst_orig_node->tt_buff)
1532                 full_table = true;
1533         else
1534                 full_table = false;
1535
1536         /* In this version, fragmentation is not implemented, then
1537          * I'll send only one packet with as much TT entries as I can
1538          */
1539         if (!full_table) {
1540                 spin_lock_bh(&req_dst_orig_node->tt_buff_lock);
1541                 tt_len = req_dst_orig_node->tt_buff_len;
1542                 tt_tot = tt_len / sizeof(struct tt_change);
1543
1544                 skb = dev_alloc_skb(sizeof(struct tt_query_packet) +
1545                                     tt_len + ETH_HLEN);
1546                 if (!skb)
1547                         goto unlock;
1548
1549                 skb_reserve(skb, ETH_HLEN);
1550                 tt_response = (struct tt_query_packet *)skb_put(skb,
1551                                 sizeof(struct tt_query_packet) + tt_len);
1552                 tt_response->ttvn = req_ttvn;
1553                 tt_response->tt_data = htons(tt_tot);
1554
1555                 tt_buff = skb->data + sizeof(struct tt_query_packet);
1556                 /* Copy the last orig_node's OGM buffer */
1557                 memcpy(tt_buff, req_dst_orig_node->tt_buff,
1558                        req_dst_orig_node->tt_buff_len);
1559
1560                 spin_unlock_bh(&req_dst_orig_node->tt_buff_lock);
1561         } else {
1562                 tt_len = (uint16_t)atomic_read(&req_dst_orig_node->tt_size) *
1563                                                 sizeof(struct tt_change);
1564                 ttvn = (uint8_t)atomic_read(&req_dst_orig_node->last_ttvn);
1565
1566                 skb = batadv_tt_response_fill_table(tt_len, ttvn,
1567                                                     bat_priv->tt_global_hash,
1568                                                     primary_if,
1569                                                     batadv_tt_global_valid,
1570                                                     req_dst_orig_node);
1571                 if (!skb)
1572                         goto out;
1573
1574                 tt_response = (struct tt_query_packet *)skb->data;
1575         }
1576
1577         tt_response->header.packet_type = BAT_TT_QUERY;
1578         tt_response->header.version = COMPAT_VERSION;
1579         tt_response->header.ttl = TTL;
1580         memcpy(tt_response->src, req_dst_orig_node->orig, ETH_ALEN);
1581         memcpy(tt_response->dst, tt_request->src, ETH_ALEN);
1582         tt_response->flags = TT_RESPONSE;
1583
1584         if (full_table)
1585                 tt_response->flags |= TT_FULL_TABLE;
1586
1587         batadv_dbg(DBG_TT, bat_priv,
1588                    "Sending TT_RESPONSE %pM via %pM for %pM (ttvn: %u)\n",
1589                    res_dst_orig_node->orig, neigh_node->addr,
1590                    req_dst_orig_node->orig, req_ttvn);
1591
1592         batadv_inc_counter(bat_priv, BAT_CNT_TT_RESPONSE_TX);
1593
1594         batadv_send_skb_packet(skb, neigh_node->if_incoming, neigh_node->addr);
1595         ret = true;
1596         goto out;
1597
1598 unlock:
1599         spin_unlock_bh(&req_dst_orig_node->tt_buff_lock);
1600
1601 out:
1602         if (res_dst_orig_node)
1603                 batadv_orig_node_free_ref(res_dst_orig_node);
1604         if (req_dst_orig_node)
1605                 batadv_orig_node_free_ref(req_dst_orig_node);
1606         if (neigh_node)
1607                 batadv_neigh_node_free_ref(neigh_node);
1608         if (primary_if)
1609                 batadv_hardif_free_ref(primary_if);
1610         if (!ret)
1611                 kfree_skb(skb);
1612         return ret;
1613
1614 }
1615 static bool batadv_send_my_tt_response(struct bat_priv *bat_priv,
1616                                        struct tt_query_packet *tt_request)
1617 {
1618         struct orig_node *orig_node = NULL;
1619         struct neigh_node *neigh_node = NULL;
1620         struct hard_iface *primary_if = NULL;
1621         uint8_t my_ttvn, req_ttvn, ttvn;
1622         int ret = false;
1623         unsigned char *tt_buff;
1624         bool full_table;
1625         uint16_t tt_len, tt_tot;
1626         struct sk_buff *skb = NULL;
1627         struct tt_query_packet *tt_response;
1628
1629         batadv_dbg(DBG_TT, bat_priv,
1630                    "Received TT_REQUEST from %pM for ttvn: %u (me) [%c]\n",
1631                    tt_request->src, tt_request->ttvn,
1632                    (tt_request->flags & TT_FULL_TABLE ? 'F' : '.'));
1633
1634
1635         my_ttvn = (uint8_t)atomic_read(&bat_priv->ttvn);
1636         req_ttvn = tt_request->ttvn;
1637
1638         orig_node = batadv_orig_hash_find(bat_priv, tt_request->src);
1639         if (!orig_node)
1640                 goto out;
1641
1642         neigh_node = batadv_orig_node_get_router(orig_node);
1643         if (!neigh_node)
1644                 goto out;
1645
1646         primary_if = batadv_primary_if_get_selected(bat_priv);
1647         if (!primary_if)
1648                 goto out;
1649
1650         /* If the full table has been explicitly requested or the gap
1651          * is too big send the whole local translation table
1652          */
1653         if (tt_request->flags & TT_FULL_TABLE || my_ttvn != req_ttvn ||
1654             !bat_priv->tt_buff)
1655                 full_table = true;
1656         else
1657                 full_table = false;
1658
1659         /* In this version, fragmentation is not implemented, then
1660          * I'll send only one packet with as much TT entries as I can
1661          */
1662         if (!full_table) {
1663                 spin_lock_bh(&bat_priv->tt_buff_lock);
1664                 tt_len = bat_priv->tt_buff_len;
1665                 tt_tot = tt_len / sizeof(struct tt_change);
1666
1667                 skb = dev_alloc_skb(sizeof(struct tt_query_packet) +
1668                                     tt_len + ETH_HLEN);
1669                 if (!skb)
1670                         goto unlock;
1671
1672                 skb_reserve(skb, ETH_HLEN);
1673                 tt_response = (struct tt_query_packet *)skb_put(skb,
1674                                 sizeof(struct tt_query_packet) + tt_len);
1675                 tt_response->ttvn = req_ttvn;
1676                 tt_response->tt_data = htons(tt_tot);
1677
1678                 tt_buff = skb->data + sizeof(struct tt_query_packet);
1679                 memcpy(tt_buff, bat_priv->tt_buff,
1680                        bat_priv->tt_buff_len);
1681                 spin_unlock_bh(&bat_priv->tt_buff_lock);
1682         } else {
1683                 tt_len = (uint16_t)atomic_read(&bat_priv->num_local_tt) *
1684                                                 sizeof(struct tt_change);
1685                 ttvn = (uint8_t)atomic_read(&bat_priv->ttvn);
1686
1687                 skb = batadv_tt_response_fill_table(tt_len, ttvn,
1688                                                     bat_priv->tt_local_hash,
1689                                                     primary_if,
1690                                                     batadv_tt_local_valid_entry,
1691                                                     NULL);
1692                 if (!skb)
1693                         goto out;
1694
1695                 tt_response = (struct tt_query_packet *)skb->data;
1696         }
1697
1698         tt_response->header.packet_type = BAT_TT_QUERY;
1699         tt_response->header.version = COMPAT_VERSION;
1700         tt_response->header.ttl = TTL;
1701         memcpy(tt_response->src, primary_if->net_dev->dev_addr, ETH_ALEN);
1702         memcpy(tt_response->dst, tt_request->src, ETH_ALEN);
1703         tt_response->flags = TT_RESPONSE;
1704
1705         if (full_table)
1706                 tt_response->flags |= TT_FULL_TABLE;
1707
1708         batadv_dbg(DBG_TT, bat_priv,
1709                    "Sending TT_RESPONSE to %pM via %pM [%c]\n",
1710                    orig_node->orig, neigh_node->addr,
1711                    (tt_response->flags & TT_FULL_TABLE ? 'F' : '.'));
1712
1713         batadv_inc_counter(bat_priv, BAT_CNT_TT_RESPONSE_TX);
1714
1715         batadv_send_skb_packet(skb, neigh_node->if_incoming, neigh_node->addr);
1716         ret = true;
1717         goto out;
1718
1719 unlock:
1720         spin_unlock_bh(&bat_priv->tt_buff_lock);
1721 out:
1722         if (orig_node)
1723                 batadv_orig_node_free_ref(orig_node);
1724         if (neigh_node)
1725                 batadv_neigh_node_free_ref(neigh_node);
1726         if (primary_if)
1727                 batadv_hardif_free_ref(primary_if);
1728         if (!ret)
1729                 kfree_skb(skb);
1730         /* This packet was for me, so it doesn't need to be re-routed */
1731         return true;
1732 }
1733
1734 bool batadv_send_tt_response(struct bat_priv *bat_priv,
1735                              struct tt_query_packet *tt_request)
1736 {
1737         if (batadv_is_my_mac(tt_request->dst)) {
1738                 /* don't answer backbone gws! */
1739                 if (batadv_bla_is_backbone_gw_orig(bat_priv, tt_request->src))
1740                         return true;
1741
1742                 return batadv_send_my_tt_response(bat_priv, tt_request);
1743         } else {
1744                 return batadv_send_other_tt_response(bat_priv, tt_request);
1745         }
1746 }
1747
1748 static void _batadv_tt_update_changes(struct bat_priv *bat_priv,
1749                                       struct orig_node *orig_node,
1750                                       struct tt_change *tt_change,
1751                                       uint16_t tt_num_changes, uint8_t ttvn)
1752 {
1753         int i;
1754         int roams;
1755
1756         for (i = 0; i < tt_num_changes; i++) {
1757                 if ((tt_change + i)->flags & TT_CLIENT_DEL) {
1758                         roams = (tt_change + i)->flags & TT_CLIENT_ROAM;
1759                         batadv_tt_global_del(bat_priv, orig_node,
1760                                              (tt_change + i)->addr,
1761                                              "tt removed by changes",
1762                                              roams);
1763                 } else {
1764                         if (!batadv_tt_global_add(bat_priv, orig_node,
1765                                                   (tt_change + i)->addr,
1766                                                   (tt_change + i)->flags, ttvn))
1767                                 /* In case of problem while storing a
1768                                  * global_entry, we stop the updating
1769                                  * procedure without committing the
1770                                  * ttvn change. This will avoid to send
1771                                  * corrupted data on tt_request
1772                                  */
1773                                 return;
1774                 }
1775         }
1776         orig_node->tt_initialised = true;
1777 }
1778
1779 static void batadv_tt_fill_gtable(struct bat_priv *bat_priv,
1780                                   struct tt_query_packet *tt_response)
1781 {
1782         struct orig_node *orig_node = NULL;
1783
1784         orig_node = batadv_orig_hash_find(bat_priv, tt_response->src);
1785         if (!orig_node)
1786                 goto out;
1787
1788         /* Purge the old table first.. */
1789         batadv_tt_global_del_orig(bat_priv, orig_node, "Received full table");
1790
1791         _batadv_tt_update_changes(bat_priv, orig_node,
1792                                   (struct tt_change *)(tt_response + 1),
1793                                   ntohs(tt_response->tt_data),
1794                                   tt_response->ttvn);
1795
1796         spin_lock_bh(&orig_node->tt_buff_lock);
1797         kfree(orig_node->tt_buff);
1798         orig_node->tt_buff_len = 0;
1799         orig_node->tt_buff = NULL;
1800         spin_unlock_bh(&orig_node->tt_buff_lock);
1801
1802         atomic_set(&orig_node->last_ttvn, tt_response->ttvn);
1803
1804 out:
1805         if (orig_node)
1806                 batadv_orig_node_free_ref(orig_node);
1807 }
1808
1809 static void batadv_tt_update_changes(struct bat_priv *bat_priv,
1810                                      struct orig_node *orig_node,
1811                                      uint16_t tt_num_changes, uint8_t ttvn,
1812                                      struct tt_change *tt_change)
1813 {
1814         _batadv_tt_update_changes(bat_priv, orig_node, tt_change,
1815                                   tt_num_changes, ttvn);
1816
1817         batadv_tt_save_orig_buffer(bat_priv, orig_node,
1818                                    (unsigned char *)tt_change, tt_num_changes);
1819         atomic_set(&orig_node->last_ttvn, ttvn);
1820 }
1821
1822 bool batadv_is_my_client(struct bat_priv *bat_priv, const uint8_t *addr)
1823 {
1824         struct tt_local_entry *tt_local_entry = NULL;
1825         bool ret = false;
1826
1827         tt_local_entry = batadv_tt_local_hash_find(bat_priv, addr);
1828         if (!tt_local_entry)
1829                 goto out;
1830         /* Check if the client has been logically deleted (but is kept for
1831          * consistency purpose)
1832          */
1833         if (tt_local_entry->common.flags & TT_CLIENT_PENDING)
1834                 goto out;
1835         ret = true;
1836 out:
1837         if (tt_local_entry)
1838                 batadv_tt_local_entry_free_ref(tt_local_entry);
1839         return ret;
1840 }
1841
1842 void batadv_handle_tt_response(struct bat_priv *bat_priv,
1843                                struct tt_query_packet *tt_response)
1844 {
1845         struct tt_req_node *node, *safe;
1846         struct orig_node *orig_node = NULL;
1847
1848         batadv_dbg(DBG_TT, bat_priv,
1849                    "Received TT_RESPONSE from %pM for ttvn %d t_size: %d [%c]\n",
1850                    tt_response->src, tt_response->ttvn,
1851                    ntohs(tt_response->tt_data),
1852                    (tt_response->flags & TT_FULL_TABLE ? 'F' : '.'));
1853
1854         /* we should have never asked a backbone gw */
1855         if (batadv_bla_is_backbone_gw_orig(bat_priv, tt_response->src))
1856                 goto out;
1857
1858         orig_node = batadv_orig_hash_find(bat_priv, tt_response->src);
1859         if (!orig_node)
1860                 goto out;
1861
1862         if (tt_response->flags & TT_FULL_TABLE)
1863                 batadv_tt_fill_gtable(bat_priv, tt_response);
1864         else
1865                 batadv_tt_update_changes(bat_priv, orig_node,
1866                                          ntohs(tt_response->tt_data),
1867                                          tt_response->ttvn,
1868                                          (struct tt_change *)(tt_response + 1));
1869
1870         /* Delete the tt_req_node from pending tt_requests list */
1871         spin_lock_bh(&bat_priv->tt_req_list_lock);
1872         list_for_each_entry_safe(node, safe, &bat_priv->tt_req_list, list) {
1873                 if (!batadv_compare_eth(node->addr, tt_response->src))
1874                         continue;
1875                 list_del(&node->list);
1876                 kfree(node);
1877         }
1878         spin_unlock_bh(&bat_priv->tt_req_list_lock);
1879
1880         /* Recalculate the CRC for this orig_node and store it */
1881         orig_node->tt_crc = batadv_tt_global_crc(bat_priv, orig_node);
1882         /* Roaming phase is over: tables are in sync again. I can
1883          * unset the flag
1884          */
1885         orig_node->tt_poss_change = false;
1886 out:
1887         if (orig_node)
1888                 batadv_orig_node_free_ref(orig_node);
1889 }
1890
1891 int batadv_tt_init(struct bat_priv *bat_priv)
1892 {
1893         int ret;
1894
1895         ret = batadv_tt_local_init(bat_priv);
1896         if (ret < 0)
1897                 return ret;
1898
1899         ret = batadv_tt_global_init(bat_priv);
1900         if (ret < 0)
1901                 return ret;
1902
1903         batadv_tt_start_timer(bat_priv);
1904
1905         return 1;
1906 }
1907
1908 static void batadv_tt_roam_list_free(struct bat_priv *bat_priv)
1909 {
1910         struct tt_roam_node *node, *safe;
1911
1912         spin_lock_bh(&bat_priv->tt_roam_list_lock);
1913
1914         list_for_each_entry_safe(node, safe, &bat_priv->tt_roam_list, list) {
1915                 list_del(&node->list);
1916                 kfree(node);
1917         }
1918
1919         spin_unlock_bh(&bat_priv->tt_roam_list_lock);
1920 }
1921
1922 static void batadv_tt_roam_purge(struct bat_priv *bat_priv)
1923 {
1924         struct tt_roam_node *node, *safe;
1925
1926         spin_lock_bh(&bat_priv->tt_roam_list_lock);
1927         list_for_each_entry_safe(node, safe, &bat_priv->tt_roam_list, list) {
1928                 if (!batadv_has_timed_out(node->first_time, ROAMING_MAX_TIME))
1929                         continue;
1930
1931                 list_del(&node->list);
1932                 kfree(node);
1933         }
1934         spin_unlock_bh(&bat_priv->tt_roam_list_lock);
1935 }
1936
1937 /* This function checks whether the client already reached the
1938  * maximum number of possible roaming phases. In this case the ROAMING_ADV
1939  * will not be sent.
1940  *
1941  * returns true if the ROAMING_ADV can be sent, false otherwise
1942  */
1943 static bool batadv_tt_check_roam_count(struct bat_priv *bat_priv,
1944                                        uint8_t *client)
1945 {
1946         struct tt_roam_node *tt_roam_node;
1947         bool ret = false;
1948
1949         spin_lock_bh(&bat_priv->tt_roam_list_lock);
1950         /* The new tt_req will be issued only if I'm not waiting for a
1951          * reply from the same orig_node yet
1952          */
1953         list_for_each_entry(tt_roam_node, &bat_priv->tt_roam_list, list) {
1954                 if (!batadv_compare_eth(tt_roam_node->addr, client))
1955                         continue;
1956
1957                 if (batadv_has_timed_out(tt_roam_node->first_time,
1958                                          ROAMING_MAX_TIME))
1959                         continue;
1960
1961                 if (!batadv_atomic_dec_not_zero(&tt_roam_node->counter))
1962                         /* Sorry, you roamed too many times! */
1963                         goto unlock;
1964                 ret = true;
1965                 break;
1966         }
1967
1968         if (!ret) {
1969                 tt_roam_node = kmalloc(sizeof(*tt_roam_node), GFP_ATOMIC);
1970                 if (!tt_roam_node)
1971                         goto unlock;
1972
1973                 tt_roam_node->first_time = jiffies;
1974                 atomic_set(&tt_roam_node->counter, ROAMING_MAX_COUNT - 1);
1975                 memcpy(tt_roam_node->addr, client, ETH_ALEN);
1976
1977                 list_add(&tt_roam_node->list, &bat_priv->tt_roam_list);
1978                 ret = true;
1979         }
1980
1981 unlock:
1982         spin_unlock_bh(&bat_priv->tt_roam_list_lock);
1983         return ret;
1984 }
1985
1986 static void batadv_send_roam_adv(struct bat_priv *bat_priv, uint8_t *client,
1987                                  struct orig_node *orig_node)
1988 {
1989         struct neigh_node *neigh_node = NULL;
1990         struct sk_buff *skb = NULL;
1991         struct roam_adv_packet *roam_adv_packet;
1992         int ret = 1;
1993         struct hard_iface *primary_if;
1994
1995         /* before going on we have to check whether the client has
1996          * already roamed to us too many times
1997          */
1998         if (!batadv_tt_check_roam_count(bat_priv, client))
1999                 goto out;
2000
2001         skb = dev_alloc_skb(sizeof(struct roam_adv_packet) + ETH_HLEN);
2002         if (!skb)
2003                 goto out;
2004
2005         skb_reserve(skb, ETH_HLEN);
2006
2007         roam_adv_packet = (struct roam_adv_packet *)skb_put(skb,
2008                                         sizeof(struct roam_adv_packet));
2009
2010         roam_adv_packet->header.packet_type = BAT_ROAM_ADV;
2011         roam_adv_packet->header.version = COMPAT_VERSION;
2012         roam_adv_packet->header.ttl = TTL;
2013         primary_if = batadv_primary_if_get_selected(bat_priv);
2014         if (!primary_if)
2015                 goto out;
2016         memcpy(roam_adv_packet->src, primary_if->net_dev->dev_addr, ETH_ALEN);
2017         batadv_hardif_free_ref(primary_if);
2018         memcpy(roam_adv_packet->dst, orig_node->orig, ETH_ALEN);
2019         memcpy(roam_adv_packet->client, client, ETH_ALEN);
2020
2021         neigh_node = batadv_orig_node_get_router(orig_node);
2022         if (!neigh_node)
2023                 goto out;
2024
2025         batadv_dbg(DBG_TT, bat_priv,
2026                    "Sending ROAMING_ADV to %pM (client %pM) via %pM\n",
2027                    orig_node->orig, client, neigh_node->addr);
2028
2029         batadv_inc_counter(bat_priv, BAT_CNT_TT_ROAM_ADV_TX);
2030
2031         batadv_send_skb_packet(skb, neigh_node->if_incoming, neigh_node->addr);
2032         ret = 0;
2033
2034 out:
2035         if (neigh_node)
2036                 batadv_neigh_node_free_ref(neigh_node);
2037         if (ret)
2038                 kfree_skb(skb);
2039         return;
2040 }
2041
2042 static void batadv_tt_purge(struct work_struct *work)
2043 {
2044         struct delayed_work *delayed_work =
2045                 container_of(work, struct delayed_work, work);
2046         struct bat_priv *bat_priv =
2047                 container_of(delayed_work, struct bat_priv, tt_work);
2048
2049         batadv_tt_local_purge(bat_priv);
2050         batadv_tt_global_roam_purge(bat_priv);
2051         batadv_tt_req_purge(bat_priv);
2052         batadv_tt_roam_purge(bat_priv);
2053
2054         batadv_tt_start_timer(bat_priv);
2055 }
2056
2057 void batadv_tt_free(struct bat_priv *bat_priv)
2058 {
2059         cancel_delayed_work_sync(&bat_priv->tt_work);
2060
2061         batadv_tt_local_table_free(bat_priv);
2062         batadv_tt_global_table_free(bat_priv);
2063         batadv_tt_req_list_free(bat_priv);
2064         batadv_tt_changes_list_free(bat_priv);
2065         batadv_tt_roam_list_free(bat_priv);
2066
2067         kfree(bat_priv->tt_buff);
2068 }
2069
2070 /* This function will enable or disable the specified flags for all the entries
2071  * in the given hash table and returns the number of modified entries
2072  */
2073 static uint16_t batadv_tt_set_flags(struct hashtable_t *hash, uint16_t flags,
2074                                     bool enable)
2075 {
2076         uint32_t i;
2077         uint16_t changed_num = 0;
2078         struct hlist_head *head;
2079         struct hlist_node *node;
2080         struct tt_common_entry *tt_common_entry;
2081
2082         if (!hash)
2083                 goto out;
2084
2085         for (i = 0; i < hash->size; i++) {
2086                 head = &hash->table[i];
2087
2088                 rcu_read_lock();
2089                 hlist_for_each_entry_rcu(tt_common_entry, node,
2090                                          head, hash_entry) {
2091                         if (enable) {
2092                                 if ((tt_common_entry->flags & flags) == flags)
2093                                         continue;
2094                                 tt_common_entry->flags |= flags;
2095                         } else {
2096                                 if (!(tt_common_entry->flags & flags))
2097                                         continue;
2098                                 tt_common_entry->flags &= ~flags;
2099                         }
2100                         changed_num++;
2101                 }
2102                 rcu_read_unlock();
2103         }
2104 out:
2105         return changed_num;
2106 }
2107
2108 /* Purge out all the tt local entries marked with TT_CLIENT_PENDING */
2109 static void batadv_tt_local_purge_pending_clients(struct bat_priv *bat_priv)
2110 {
2111         struct hashtable_t *hash = bat_priv->tt_local_hash;
2112         struct tt_common_entry *tt_common_entry;
2113         struct tt_local_entry *tt_local_entry;
2114         struct hlist_node *node, *node_tmp;
2115         struct hlist_head *head;
2116         spinlock_t *list_lock; /* protects write access to the hash lists */
2117         uint32_t i;
2118
2119         if (!hash)
2120                 return;
2121
2122         for (i = 0; i < hash->size; i++) {
2123                 head = &hash->table[i];
2124                 list_lock = &hash->list_locks[i];
2125
2126                 spin_lock_bh(list_lock);
2127                 hlist_for_each_entry_safe(tt_common_entry, node, node_tmp,
2128                                           head, hash_entry) {
2129                         if (!(tt_common_entry->flags & TT_CLIENT_PENDING))
2130                                 continue;
2131
2132                         batadv_dbg(DBG_TT, bat_priv,
2133                                    "Deleting local tt entry (%pM): pending\n",
2134                                    tt_common_entry->addr);
2135
2136                         atomic_dec(&bat_priv->num_local_tt);
2137                         hlist_del_rcu(node);
2138                         tt_local_entry = container_of(tt_common_entry,
2139                                                       struct tt_local_entry,
2140                                                       common);
2141                         batadv_tt_local_entry_free_ref(tt_local_entry);
2142                 }
2143                 spin_unlock_bh(list_lock);
2144         }
2145
2146 }
2147
2148 static int batadv_tt_commit_changes(struct bat_priv *bat_priv,
2149                                     unsigned char **packet_buff,
2150                                     int *packet_buff_len, int packet_min_len)
2151 {
2152         uint16_t changed_num = 0;
2153
2154         if (atomic_read(&bat_priv->tt_local_changes) < 1)
2155                 return -ENOENT;
2156
2157         changed_num = batadv_tt_set_flags(bat_priv->tt_local_hash,
2158                                           TT_CLIENT_NEW, false);
2159
2160         /* all reset entries have to be counted as local entries */
2161         atomic_add(changed_num, &bat_priv->num_local_tt);
2162         batadv_tt_local_purge_pending_clients(bat_priv);
2163         bat_priv->tt_crc = batadv_tt_local_crc(bat_priv);
2164
2165         /* Increment the TTVN only once per OGM interval */
2166         atomic_inc(&bat_priv->ttvn);
2167         batadv_dbg(DBG_TT, bat_priv,
2168                    "Local changes committed, updating to ttvn %u\n",
2169                    (uint8_t)atomic_read(&bat_priv->ttvn));
2170         bat_priv->tt_poss_change = false;
2171
2172         /* reset the sending counter */
2173         atomic_set(&bat_priv->tt_ogm_append_cnt, TT_OGM_APPEND_MAX);
2174
2175         return batadv_tt_changes_fill_buff(bat_priv, packet_buff,
2176                                            packet_buff_len, packet_min_len);
2177 }
2178
2179 /* when calling this function (hard_iface == primary_if) has to be true */
2180 int batadv_tt_append_diff(struct bat_priv *bat_priv,
2181                           unsigned char **packet_buff, int *packet_buff_len,
2182                           int packet_min_len)
2183 {
2184         int tt_num_changes;
2185
2186         /* if at least one change happened */
2187         tt_num_changes = batadv_tt_commit_changes(bat_priv, packet_buff,
2188                                                   packet_buff_len,
2189                                                   packet_min_len);
2190
2191         /* if the changes have been sent often enough */
2192         if ((tt_num_changes < 0) &&
2193             (!batadv_atomic_dec_not_zero(&bat_priv->tt_ogm_append_cnt))) {
2194                 batadv_tt_realloc_packet_buff(packet_buff, packet_buff_len,
2195                                               packet_min_len, packet_min_len);
2196                 tt_num_changes = 0;
2197         }
2198
2199         return tt_num_changes;
2200 }
2201
2202 bool batadv_is_ap_isolated(struct bat_priv *bat_priv, uint8_t *src,
2203                            uint8_t *dst)
2204 {
2205         struct tt_local_entry *tt_local_entry = NULL;
2206         struct tt_global_entry *tt_global_entry = NULL;
2207         bool ret = false;
2208
2209         if (!atomic_read(&bat_priv->ap_isolation))
2210                 goto out;
2211
2212         tt_local_entry = batadv_tt_local_hash_find(bat_priv, dst);
2213         if (!tt_local_entry)
2214                 goto out;
2215
2216         tt_global_entry = batadv_tt_global_hash_find(bat_priv, src);
2217         if (!tt_global_entry)
2218                 goto out;
2219
2220         if (!_batadv_is_ap_isolated(tt_local_entry, tt_global_entry))
2221                 goto out;
2222
2223         ret = true;
2224
2225 out:
2226         if (tt_global_entry)
2227                 batadv_tt_global_entry_free_ref(tt_global_entry);
2228         if (tt_local_entry)
2229                 batadv_tt_local_entry_free_ref(tt_local_entry);
2230         return ret;
2231 }
2232
2233 void batadv_tt_update_orig(struct bat_priv *bat_priv,
2234                            struct orig_node *orig_node,
2235                            const unsigned char *tt_buff, uint8_t tt_num_changes,
2236                            uint8_t ttvn, uint16_t tt_crc)
2237 {
2238         uint8_t orig_ttvn = (uint8_t)atomic_read(&orig_node->last_ttvn);
2239         bool full_table = true;
2240
2241         /* don't care about a backbone gateways updates. */
2242         if (batadv_bla_is_backbone_gw_orig(bat_priv, orig_node->orig))
2243                 return;
2244
2245         /* orig table not initialised AND first diff is in the OGM OR the ttvn
2246          * increased by one -> we can apply the attached changes
2247          */
2248         if ((!orig_node->tt_initialised && ttvn == 1) ||
2249             ttvn - orig_ttvn == 1) {
2250                 /* the OGM could not contain the changes due to their size or
2251                  * because they have already been sent TT_OGM_APPEND_MAX times.
2252                  * In this case send a tt request
2253                  */
2254                 if (!tt_num_changes) {
2255                         full_table = false;
2256                         goto request_table;
2257                 }
2258
2259                 batadv_tt_update_changes(bat_priv, orig_node, tt_num_changes,
2260                                          ttvn, (struct tt_change *)tt_buff);
2261
2262                 /* Even if we received the precomputed crc with the OGM, we
2263                  * prefer to recompute it to spot any possible inconsistency
2264                  * in the global table
2265                  */
2266                 orig_node->tt_crc = batadv_tt_global_crc(bat_priv, orig_node);
2267
2268                 /* The ttvn alone is not enough to guarantee consistency
2269                  * because a single value could represent different states
2270                  * (due to the wrap around). Thus a node has to check whether
2271                  * the resulting table (after applying the changes) is still
2272                  * consistent or not. E.g. a node could disconnect while its
2273                  * ttvn is X and reconnect on ttvn = X + TTVN_MAX: in this case
2274                  * checking the CRC value is mandatory to detect the
2275                  * inconsistency
2276                  */
2277                 if (orig_node->tt_crc != tt_crc)
2278                         goto request_table;
2279
2280                 /* Roaming phase is over: tables are in sync again. I can
2281                  * unset the flag
2282                  */
2283                 orig_node->tt_poss_change = false;
2284         } else {
2285                 /* if we missed more than one change or our tables are not
2286                  * in sync anymore -> request fresh tt data
2287                  */
2288                 if (!orig_node->tt_initialised || ttvn != orig_ttvn ||
2289                     orig_node->tt_crc != tt_crc) {
2290 request_table:
2291                         batadv_dbg(DBG_TT, bat_priv,
2292                                    "TT inconsistency for %pM. Need to retrieve the correct information (ttvn: %u last_ttvn: %u crc: %u last_crc: %u num_changes: %u)\n",
2293                                    orig_node->orig, ttvn, orig_ttvn, tt_crc,
2294                                    orig_node->tt_crc, tt_num_changes);
2295                         batadv_send_tt_request(bat_priv, orig_node, ttvn,
2296                                                tt_crc, full_table);
2297                         return;
2298                 }
2299         }
2300 }
2301
2302 /* returns true whether we know that the client has moved from its old
2303  * originator to another one. This entry is kept is still kept for consistency
2304  * purposes
2305  */
2306 bool batadv_tt_global_client_is_roaming(struct bat_priv *bat_priv,
2307                                         uint8_t *addr)
2308 {
2309         struct tt_global_entry *tt_global_entry;
2310         bool ret = false;
2311
2312         tt_global_entry = batadv_tt_global_hash_find(bat_priv, addr);
2313         if (!tt_global_entry)
2314                 goto out;
2315
2316         ret = tt_global_entry->common.flags & TT_CLIENT_ROAM;
2317         batadv_tt_global_entry_free_ref(tt_global_entry);
2318 out:
2319         return ret;
2320 }